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As sustainable building design practices become more prevalent in today’s construction market, designers are looking to alternative materials for novel design strategies. This paper presents a case study comparing the sustainability performance of cross laminated timber (CLT) and reinforced concrete. A comparative sustainability assessment of cross laminated timber and concrete, considering economic, environmental, and social aspects was performed. Environmental impact is measured in terms of CO2 equivalent, economic impact is measured with total sector cost (including sector interdependencies), and qualitative metrics were considered for social impact. In order to conduct an accurate performance comparison, a functional unit of building facade volume was chosen for each product. For this paper, several end-of-life strategies were modeled for CLT and concrete facades. To understand environmental, economic, and social impact, three different scenarios were analyzed to compare performance of both CLT and concrete, including cradle to gate product manufacturing, manufacturing with landfill end-of-life, and manufacturing with recycling end-of-life. Environmental LCA was modeled using GaBi 5.0 Education Edition, which includes its own database for elements including materials, processes, and transportation. To compare the economic impact, Carnegie Mellon’s EIO-LCA online tool is used. Finally, social life cycle impact was considered by identifying process attributes of both products that affect the social domain. Based on this analysis, the use of CLT has a significantly lower environmental impact than concrete, however there are additional costs.

As demand for electricity in the U.S. continues to increase, it is necessary to explore the means through which the modern power supply system can accommodate both increasing affluence (which is accompanied by increased per-capita consumption) and the continually growing global population. Though there has been a great deal of research into the theoretical optimization of large-scale power systems, research into the use of an existing power system as a foundation for this growth has yet to be fully explored. Current successful and robust power generation systems that have significant renewable energy penetration—despite not having been optimized a priori—can be used to inform the advancement of modern power systems to accommodate the increasing demand for electricity. This work explores how an accurate and state-of-the-art computational model of a large, regional energy system can be employed as part of an overarching power systems optimization scheme that looks to inform the decision making process for next generation power supply systems. Research scenarios that explore an introductory multi-objective power flow analysis for a case study involving a regional portion of a large grid will be explored, along with a discussion of future research directions.

Optimizing the topology of complex infrastructure systems can minimize the impact of cascading failures due to an initiating failure event. This paper presents a model-based design approach for the concept-stage robust design of complex infrastructure systems, as an alternative to modern network analysis methods. This approach focuses on system performance after cascading has occurred and examines design tradeoffs of the resultant (or degraded) system state. In this research, robustness is classically defined as the invariability of system performance due to uncertain failure events, implying that a robust network has the ability to meet minimum performance requirements despite the impact of cascading failures. This research is motivated by catastrophic complex infrastructure system failures such as the August 13th Blackout of 2003, highlighting the vulnerability of systems such as the North American power grid (NAPG). A mathematical model was developed using an adjacency matrix, where removing network connections simulates uncertain failure events. Performance degradation is iteratively calculated as failures cascade throughout the system, and robustness is measured by the lack of performance variability over multiple cascading failure scenarios. Two case studies are provided: an extrapolated IEEE 14 test bus and the Oregon State University (OSU) campus power network. The overarching goal of this research is to understand key system design tradeoffs between robustness, performance objectives, and cost, and explore the benefits of optimizing network topologies during the concept-stage design of these systems (e.g., microgrids).

Satellite-linked platform terminal transmitters (PTTs) enable biologists to study movements of sea turtles. However, PTTs often fail due to limited battery life, antenna breakage, biofouling, saltwater switch failure, and premature tag detachment. Also, PTTs induce hydrodynamic drag and may bias sea turtle behavior. Advances in technology continue to improve PTTs, however, design opportunities remain so that deployment duration is increased and behavioral biases are limited. We review how PTTs are used to obtain information on sea turtle biology, the current state-of-the-art, review recent innovations and highlight potential areas for design improvements. There remain several areas to focus on design improvements: (1) improve attachment methods so as to stretch as juveniles grow but do not add additional height to tag profile, (2) improve tag profile and attachment location on the turtle carapace to limit hydrodynamic drag, (3) experiment with different energy harvesting options to extend deployment duration, and (4) improve antenna design and material to enhance robustness and transmission quality. Capitalizing on emerging technology that allows for increasing miniaturization will likely create tags that extend deployment duration and induce negligible behavioral biases and will create data that best represents the true biology of sea turtle species in-water.