Composite material systems for hydrogen management

The task of managing hydrogen entry into elevated temperature structural materials employed in turbomachinery is a critical engineering area for propulsion systems employing hydrogen or decomposable hydrocarbons as fuel. Extant structural materials, such as the Inconel series, are embrittled by the ingress of hydrogen in service, leading to a loss of endurance and general deterioration of load-bearing dependability. Although the development of hydrogen-insensitive material systems is an obvious engineering option, to date insensitive systems cannot meet the time-temperature-loading service extremes encountered. A short-term approach that is both feasible and technologically sound is the development and employment of hydrogen barrier coatings. The present project is concerned with developing, analyzing, and physically testing laminate composite hydrogen barrier systems, employing Inconel 718 as the structural material to be protected. Barrier systems will include all metallic, metallic-to-ceramic, and, eventually, metallic/ceramic composites as the lamellae. Since space propulsion implies repetitive engine firings without earth-based inspection and repair, coating durability will be closely examined, and testing regimes will include repetitive thermal cycling to simulate damage accumulation. The target accomplishments include: generation of actual hydrogen permeation data for metallic, ceramic-metallic, and hybrid metallic/ceramic composition barrier systems, practically none of which is currently extant; definition of physical damage modes imported to barrier systems due to thermal cycling, both transient temperature profiles and steady-state thermal mismatch stress states being examined as sources of damage; and computational models that incorporate general laminate schemes as described above, including manufacturing realities such as porosity, and whatever defects are introduced through service and characterized during the experimental programs

Scalable data clustering using GPUs

The computational demands of multivariate clustering grow rapidly, and therefore processing large data sets, like those found in flow cytometry data, is very time consuming on a single CPU. Fortunately these techniques lend themselves naturally to large scale parallel processing. To address the computational demands, graphics processing units, specifically NVIDIA\u27s CUDA framework and Tesla architecture, were investigated as a low-cost, high performance solution to a number of clustering algorithms. C-means and Expectation Maximization with Gaussian mixture models were implemented using the CUDA framework. The algorithm implementations use a hybrid of CUDA, OpenMP, and MPI to scale to many GPUs on multiple nodes in a high performance computing environment. This framework is envisioned as part of a larger cloud-based workflow service where biologists can apply multiple algorithms and parameter sweeps to their data sets and quickly receive a thorough set of results that can be further analyzed by experts. Improvements over previous GPU-accelerated implementations range from 1.42x to 21x for C-means and 3.72x to 5.65x for the Gaussian mixture model on non-trivial data sets. Using a single NVIDIA GTX 260 speedups are on average 90x for C-means and 74x for Gaussians with flow cytometry files compared to optimized C code running on a single core of a modern Intel CPU. Using the TeraGrid Lincoln high performance cluster at NCSA C-means achieves 42% parallel efficiency and a CPU speedup of 4794x with 128 Tesla C1060 GPUs. The Gaussian mixture model achieves 72% parallel efficiency and a CPU speedup of 6286x

How does composting at school change the way middle school students perceive their ability to positively impact the earth?

The research question addressed in this project is: how does composting at school change the way middle school students perceive their ability to positively impact the earth? The motivating factor for this capstone was the lack of awareness middle school students seem to have in regards to the waste they create and how to handle their waste. This capstone delves into the impacts of service learning combined with environmentalism. Since service learning is most impactful when it is student-led, students brainstormed ideas around waste management at their school and concluded that composting should be part of the plan. Students designed, built, and decorated a wooden composting bin that will be used to help start the process at school in the following school year. The researcher describes both positive and negative shifts in students’ attitudes towards their ability to make a difference for the environment as a result of the study

Survey of hydrogen production and utilization methods. Volume 1: Executive summary

The use of hydrogen as a synthetic fuel is considered. Processes for the production of hydrogen are described along with the present and future industrial uses of hydrogen as a fuel and as a chemical feedstock. Novel and unconventional hydrogen-production techniques are evaluated, with emphasis placed on thermochemical and electrolytic processes. Potential uses for hydrogen as a fuel in industrial and residential applications are identified and reviewed in the context of anticipated U.S. energy supplies and demands. A detailed plan for the period from 1975 to 1980 prepared for research on and development of hydrogen as an energy carrier is included

An economic survey of New Zealand town milk producers 1976-77

This report is the fourth in an annual series of economic surveys of New Zealand town milk supply farms. These surveys have been undertaken by the Agricultural Economics Research Unit at Lincoln College on behalf of the New Zealand Milk Board and the Town Milk Producers Federation of New Zealand (Inc.) As in the past the major objective of this survey has been to estimate the average net farm income received by town milk producers in New Zealand. In addition, however, the opportunity provided by the surveys has been used to collect additional data so that a more comprehensive profile of the industry emerges

Dairy farming with reduced inductions

The New Zealand (NZ) dairy industry is reliant on seasonal pasture production and a concentrated calving interval to best match pasture supply and animal demand. To achieve this goal, some farmers induce lactation in late calving cows. This has animal welfare implications, which could result in non-tariff trade barriers to NZ dairy products (Blackett, Compton and Glassey, C. 2006, Stevens, J., Burton, L, Rendel, J. 2000). Additionally there are concerns with drug residues in the milk from herds where a large percentage of cows are induced. New standards were introduced in the 2010-11 season by the NZ Veterinarians Association (NZVA), Dairy NZ, Dairy Companies Association of NZ (DCANZ) and Federated Farmers. In the 2011-12 season the level of inductions within an individual herd will not exceed 8% reducing to 4% in 2012-13. There will be requirements for information about the stage of pregnancy; the age of the cow (under eight years old) and body condition score (4.5 to 6.5). Although this reduction may seem onerous, the NZVA has stated that only 3% of the national herd was induced in the season just finished, with 98% of farms being under 15% (Benny 2011). A survey of Canterbury dairy farmers in 2008 found that 36% operate a nil induction policy (Pangborn, 2008). With reduced levels of inductions farmers will be forced to adopt an eight week mating system if they are to maintain the traditional calving patterns. If the number of late calving cows cannot be reduced to fewer than 4%, then a larger number of cows will be culled. If a pregnant cow is worth $2,000 and a non-pregnant cow$500 there could be significant capital losses. The purpose of this paper is to review the basics of getting cows in calf and strategies for reduced inductions, discuss the results of the nil induction policy of the Lincoln University Dairy Farm (LUDF), and look at the plan of one Canterbury farm to meet the new guidelines