831 research outputs found
This Is Not About Cows: Historic and Contemporary Challenges to South-Central Madagascar’s Cattle Systems
Madagascar’s most cattle-dependent regions have, in recent years, been surrounded by narratives of a sudden and violent decline in both the sheer number of and benefits conferred by the nation’s distinctive zebu cattle, narratives which largely attribute this decline to theft and insecurity. This paper examines the broader state of cattle-based livelihoods in two such regions, Haute Matsiatra and Ihorombe, through evidence garnered from semi-structured interviews conducted over three weeks in the major cattle market towns of Ambalavao and Ihosy, and in the rural commune of Sakaviro, five kilometers south of Ambalavao. By incorporating secondary historical sources and recent work from both Malagasy and Western academics, the paper finds that the cattle economy has cyclically experienced high levels of related violence, foreign involvement in cattle trafficking, and conflict between and among the local and Malagasy state institutions involved in the process. However, the paper also finds that this historically cyclical system is under increasing duress from two mutually worsening sets of stressors: one constituted by deepening poverty, environmental adversity, and population growth, the other a pervasive process of social disintegration within pastoralists communities and the institutions that work with them. It concludes with a set of recommendations for relevant actors in an attempt to avoid the worst-case scenario- the collapse of cattle-based livelihoods due to a rapid decline in Madagascar’s cattle populatio
Managing Tanks as a Portfolio of Assets
PresentationThe capital investment in tank storage is a critical component of most energy companies’ business model. Decisions managing these assets are driven by the organization’s overall performance objectives, business policies, balancing the risks and returns associated with different resource allocations. The discussion that follows in the body of this paper has two objectives: The first is to describe a foundation for evaluating decisions about managing tank risk that takes into account all the risk assessment techniques traditionally used but adds to this a way to incorporate these findings into a decision context that also views tanks as part of an organization’s overall business model and managed as part of the organization’s overall portfolio of assets supporting its business model. The second objective is to show there are basic analytical tools that add precision to the perspective described in the first objective through straight-forward quantification
Spacecraft design project: High latitude communications satellite
The spacecraft design project was part of AE-4871, Advanced Spacecraft Design. The project was intended to provide experience in the design of all major components of a satellite. Each member of the class was given primary responsibility for a subsystem or design support function. Support was requested from the Naval Research Laboratory to augment the Naval Postgraduate School faculty. Analysis and design of each subsystem was done to the extent possible within the constraints of an eleven week quarter and the design facilities (hardware and software) available. The project team chose to evaluate the design of a high latitude communications satellite as representative of the design issues and tradeoffs necessary for a wide range of satellites. The High-Latitude Communications Satellite (HILACS) will provide a continuous UHF communications link between stations located north of the region covered by geosynchronous communications satellites, i.e., the area above approximately 60 N latitude. HILACS will also provide a communications link to stations below 60 N via a relay Net Control Station (NCS), which is located with access to both the HILACS and geosynchronous communications satellites. The communications payload will operate only for that portion of the orbit necessary to provide specified coverage
Tree growth and timber returns for an agroforestry trial in Goldsboro, North Carolina
Paper presented at the 12th North American Agroforesty Conference, which was held June 4-9, 2011 in Athens, Georgia.In Ashton, S. F., S.W. Workman, W.G. Hubbard and D.J. Moorhead, eds. Agroforestry: A Profitable Land Use. Proceedings, 12th North American Agroforestry Conference, Athens, GA, June 4-9, 2011.A 17 acre (6.9 ha) agroforestry research and extension alley cropping trial was established at the Center for Environmental Farming Systems in Goldsboro, North Carolina in January 2007, with a randomized block design with five replications. The demonstration planted rows of loblolly pine (Pinus taeda), longleaf pine (Pinus palustris), and cherrybark oak (Quercus pagoda), with crop lands in alleys of 40 ft or 80 ft (12.2 to 24.4 m) wide between the tree rows. Crops of soybeans (Glycine max) and corn (Zea mays) were planted in alternating years since establishment. As of 2011, survival rates were 93 [percent] for cherrybark oak, 88 [percent] for longleaf pine, and 97 [percent] for loblolly pine. Average diameter at ground level was 1.0 in (2.5 cm) for cherrybark oak, 2.1 in (5.3 cm) for longleaf, and 3.2 in (8.1 cm) for loblolly. Heights averaged 4.6 ft (1.4 m) for cherrybark oak, 5.2 ft (1.6 m) for longleaf, and 10.4 ft (3.2 m) for loblolly. Growth, yield, and economic projections for traditional timber production indicated that species volumes and values tracked the current height and diameter relationships. Loblolly pine had the largest projected internal rate of return, at 7.2 [percent], followed by longleaf pine at 3.5 [percent], and cherrybark oak at 2.9 [percent]. There might be more loss in crop and silvopasture production with loblolly, however, and production of pine straw for longleaf or game mast for cherrybark oak may offer other benefits. Crop yields on the sandy soils were very poor during the four years observed.Viola Glenn (1), Russell Myers (1), Frederick Cubbage (1),Hayley Stevenson (1), Dan Robison (1), Paul Mueller (2) and Ron Myers (3) ; 1. Department of Forestry and Environmental Resources, North Carolina State University. 2. Department of Crop Science, North Carolina State University. 3. North Carolina Division of Forest Resources.Includes bibliographical references
Probing Exotic Physics With Cosmic Neutrinos
Traditionally, collider experiments have been the primary tool used in
searching for particle physics beyond the Standard Model. In this talk, I will
discuss alternative approaches for exploring exotic physics scenarios using
high energy and ultra-high energy cosmic neutrinos. Such neutrinos can be used
to study interactions at energies higher, and over baselines longer, than those
accessible to colliders. In this way, neutrino astronomy can provide a window
into fundamental physics which is highly complementary to collider techniques.
I will discuss the role of neutrino astronomy in fundamental physics,
considering the use of such techniques in studying several specific scenarios
including low scale gravity models, Standard Model electroweak instanton
induced interactions, decaying neutrinos and quantum decoherence.Comment: 11 pages, 6 figures; For the proceedings of From Colliders To Cosmic
Rays, Prague, Czech Republic, September 7-13, 200
Effective Actions of Matrix Models on Homogeneous Spaces
We evaluate the effective actions of supersymmetric matrix models on fuzzy
S^2\times S^2 up to the two loop level. Remarkably it turns out to be a
consistent solution of IIB matrix model. Based on the power counting and SUSY
cancellation arguments, we can identify the 't Hooft coupling and large N
scaling behavior of the effective actions to all orders. In the large N limit,
the quantum corrections survive except in 2 dimensional limits. They are O(N)
and O(N^{4\over 3}) for 4 and 6 dimensional spaces respectively. We argue that
quantum effects single out 4 dimensionality among fuzzy homogeneous spaces.Comment: 28 pages, 1 figure, published version in Nucl. Phys.
Quantum Corrections on Fuzzy Sphere
We investigate quantum corrections in non-commutative gauge theory on fuzzy
sphere. We study translation invariant models which classically favor a single
fuzzy sphere with U(1) gauge group. We evaluate the effective actions up to the
two loop level. We find non-vanishing quantum corrections at each order even in
supersymmetric models. In particular the two loop contribution favors U(n)
gauge group over U(1) contrary to the tree action in a deformed IIB matrix
model with a Myers term. We further observe close correspondences to 2
dimensional quantum gravity.Comment: 27 pages, 1 figure, published version in Nucl Phys.
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