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2009

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Articles 4381 - 4410 of 7616

Full-Text Articles in Physical Sciences and Mathematics

Collapsible Graphs And Reductions Of Line Graphs, Zhi-Hong Chen, Peter C.B. Lam, Wai-Chee Shiu Jan 2009

Collapsible Graphs And Reductions Of Line Graphs, Zhi-Hong Chen, Peter C.B. Lam, Wai-Chee Shiu

Scholarship and Professional Work - LAS

A graph G is collapsible if for every even subset X ⊆ V ( G ) , G has a subgraph such that G − E ( Γ ) is connected and the set of odd-degree vertices of Γ is X . A graph obtained by contracting all the non-trivial collapsible subgraphs of G is called the reduction of G . In this paper, we characterize graphs of diameter two in terms of collapsible subgraphs and investigate the relationship between the line graph of the reduction and the reduction of the line graph. Our results extend former results in [H.-J. …

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Detection, Occurrence, And Fate Of Emerging Contaminants In Agricultural Environments (2009), Daniel D. Snow, Shannon L. Bartelt-Hunt, Shannon Devivo, Samuel Saunders, David A. Cassada Jan 2009

Detection, Occurrence, And Fate Of Emerging Contaminants In Agricultural Environments (2009), Daniel D. Snow, Shannon L. Bartelt-Hunt, Shannon Devivo, Samuel Saunders, David A. Cassada

Nebraska Water Center: Faculty Publications

Frequently studied environmental contaminants in agricultural systems include nutrients, sediments, and pesticides. These groups of contaminants typically occur at easily measured concentrations in surface run-off in agricultural watersheds. Nutrients, especially nitrogen, and pesticides have also been shown to impact ground water quality in areas susceptible to contamination. Less well-known are environmental impacts of newer classes of contaminants such as pharmaceuticals, steroids, antibiotic-resistance genes and prion proteins. These “emerging” contaminants clearly have potential to enter the environment and cause known or suspected adverse ecological or human health effects. Release of these contaminants to the environment often has occurred for quite some …

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Investigation Of Growth Phases For Bottlenose Dolphins Using A Bayesian Modeling Approach, Wayne Mcfee, John Schwacke, Megan Stolen, Keith Mullin, Lori Schwacke Jan 2009

Investigation Of Growth Phases For Bottlenose Dolphins Using A Bayesian Modeling Approach, Wayne Mcfee, John Schwacke, Megan Stolen, Keith Mullin, Lori Schwacke

United States Department of Commerce: Staff Publications

The Gompertz function is the most commonly used growth function for cetacean studies. However, this function cannot represent multiple phases of growth. In this study, we present a Bayesian framework fitting parameters of a triple-logistic growth function to describe multiple phases of growth for bottlenose dolphins (Tursiops truncatus), simultaneously fitting and comparing all growth parameters between South Carolina (SC), Mississippi Sound (MSS), and Indian River Lagoon (IRL) cohorts. The fitted functions indicated a preliminary early, rapid growth phase, followed by a second phase of slower growth, and then a moderate growth spurt later in life. Growth parameters between …

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Population Structure Of Island-Associated Dolphins: Evidence From Photo-Identification Of Common Bottlenose Dolphins (Tursiops Truncates) In The Main Hawaiian Islands, Robin Baird, Antoinette Gorgone, Daniel Mcsweeney, Allan Ligon, Mark Deakos, Daniel Webster, Gregory Schorr, Karen Martien, Dan Salden, Sabre Mahaffy Jan 2009

Population Structure Of Island-Associated Dolphins: Evidence From Photo-Identification Of Common Bottlenose Dolphins (Tursiops Truncates) In The Main Hawaiian Islands, Robin Baird, Antoinette Gorgone, Daniel Mcsweeney, Allan Ligon, Mark Deakos, Daniel Webster, Gregory Schorr, Karen Martien, Dan Salden, Sabre Mahaffy

United States Department of Commerce: Staff Publications

Management agencies often use geopolitical boundaries as proxies for biological boundaries. In Hawaiian waters a single stock is recognized of common bottlenose dolphins, Tursiops truncatus, a species that is found both in open water and nearshore among the main Hawaiian Islands. To assess population structure, we photo-identified 336 distinctive individuals from the main Hawaiian Islands, from 2000 to 2006. Their generally shallow-water distribution, and numerous within-year and between-year resightings within island areas suggest that individuals are resident to the islands, rather than part of an offshore population moving through the area. Comparisons of identifications obtained from Kaua‘i/Ni‘ihau, O‘ahu, the …

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Movements And Diving Behavior Of Pelagic Spotted Dolphins, Michael Scott, Susan Chivers Jan 2009

Movements And Diving Behavior Of Pelagic Spotted Dolphins, Michael Scott, Susan Chivers

United States Department of Commerce: Staff Publications

We radio tracked 20 pantropical spotted dolphins (Stenella attenuate) in the pelagic waters of the eastern tropical Pacific Ocean during three research cruises in 1992, 1993, and 2001. Dolphins were tracked for up to 6 d from 20 to 1,000 km offshore. Seventeen of these dolphins also carried time–depth recorders, nine of which were recovered with a combined total of 477 h of dive data. The movement data suggested that the dolphins associate with areas of relatively high biological productivity. Dolphins close to shore moved along the continental slope, while some dolphins traveled farther offshore along thermocline “ridges.” …

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Behavior Of Melon-Headed Whales, Peponocephala Electra, Near Oceanic Islands, Robert L. Brownell Jr., Katherine Ralls, Simone Baumann-Pickering, M. Michael Poole Jan 2009

Behavior Of Melon-Headed Whales, Peponocephala Electra, Near Oceanic Islands, Robert L. Brownell Jr., Katherine Ralls, Simone Baumann-Pickering, M. Michael Poole

United States Department of Commerce: Staff Publications

Southall et al. (2006) concluded that a near mass stranding (MS) of melon-headed whales (MHWs), Peponocephala electra, in Hanalei Bay, Kauai, Hawaii, on 3–4 July 2004, was likely related to the operation of mid-frequency sonars (MFS). However, subsequent authors argued that the nearly simultaneous entry of MHWs into Sasanhaya Bay, Rota (∼5,740 km away) made this conclusion untenable. They suggested that both sightings, and other MSs of MHWs, could be related to lunar cycles. To resolve this question, we reviewed information on the biology and behavior of MHWs and compared the two sightings to observations of MHWs around Palmyra …

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Adaptations In A Hierarchical Food Web Of Southeastern Lake Michigan, Ann E. Krause, Ken A. Frank, Michael L. Jones, Thomas F. Nalepa, Richard P. Barbiero, Charles P. Madenjian, Megan Agy, Marlene S. Evans, William W. Taylor, Doran M. Mason, Nancy J. Leonard Jan 2009

Adaptations In A Hierarchical Food Web Of Southeastern Lake Michigan, Ann E. Krause, Ken A. Frank, Michael L. Jones, Thomas F. Nalepa, Richard P. Barbiero, Charles P. Madenjian, Megan Agy, Marlene S. Evans, William W. Taylor, Doran M. Mason, Nancy J. Leonard

United States Department of Commerce: Staff Publications

Two issues in ecological network theory are: (1) how to construct an ecological network model and (2) how do entire networks (as opposed to individual species) adapt to changing conditions? We present a novel method for constructing an ecological network model for the food web of southeastern Lake Michigan (USA) and we identify changes in key system properties that are large relative to their uncertainty as this ecological network adapts fromone time point to a second time point in response to multiple perturbations. To construct our foodweb for southeastern Lake Michigan,we followed the list of seven recommendations outlined in Cohen …

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Recent Changes In Benthic Macroinvertebrate Populations In Lake Huron And Impact On The Diet Of Lake Whitefish (Coregonus Clupeaformis), Thomas F. Nalepa, Steven A. Pothoven, David L. Fanslow Jan 2009

Recent Changes In Benthic Macroinvertebrate Populations In Lake Huron And Impact On The Diet Of Lake Whitefish (Coregonus Clupeaformis), Thomas F. Nalepa, Steven A. Pothoven, David L. Fanslow

United States Department of Commerce: Staff Publications

Surveys of the benthic macroinvertebrate community were conducted in the main basin of Lake Huron in 2000 and 2003, and corresponding studies of lake whitefish diets were conducted in 2002-2004. Populations of three major benthic taxa, Diporeia spp., Sphaeriidae, and Chironomidae, declined dramatically between 2000 and 2003, with densities declining 57%, 74%, and 75% over this 3-year period. By 2003, Diporeia, an important food source for lake whitefish, was gone or rare at depths <50 m except in the far northeastern portion of the lake. In contrast, densities of the Dreissena bugensis (quagga mussel) increased between 2000 and 2003, particularly at the 31-50 m depth interval, while densities of the zebra mussel Dreissena polymorpha remained stable. …

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Draft U.S. Pacific Marine Mammal Stock Assessments: 2009, James V. Carretta, Karin A. Forney, Mark S. Lowry, Jay Barlow, Jason Baker, Dave Johnston, Brad Hanson, Robert L. Brownell Jr., Jooke Robbins, David K. Mattila, Katherine Ralls, Marcia M. Muto, Deanna Lynch, Lilian Carswell Jan 2009

Draft U.S. Pacific Marine Mammal Stock Assessments: 2009, James V. Carretta, Karin A. Forney, Mark S. Lowry, Jay Barlow, Jason Baker, Dave Johnston, Brad Hanson, Robert L. Brownell Jr., Jooke Robbins, David K. Mattila, Katherine Ralls, Marcia M. Muto, Deanna Lynch, Lilian Carswell

United States Department of Commerce: Staff Publications

Under the 1994 amendments to the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (USFWS) are required to publish Stock Assessment Reports for all stocks of marine mammals within U.S. waters, to review new information every year for strategic stocks and every three years for non-strategic stocks, and to update the stock assessment reports when significant new information becomes available. This report presents stock assessments for 13 Pacific marine mammal stocks under NMFS jurisdiction, including 8 “strategic” stocks and 5 “non-strategic” stocks (see summary table). A new stock assessment for …

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Cetaceans Of Southeast Alaska: Distribution And Seasonal Occurrence, Marilyn E. Dahlheim, Janice M. Waite, Paula A. White Jan 2009

Cetaceans Of Southeast Alaska: Distribution And Seasonal Occurrence, Marilyn E. Dahlheim, Janice M. Waite, Paula A. White

United States Department of Commerce: Staff Publications

Aim To assess the distribution, group size, seasonal occurrence and annual trends of cetaceans.

Location The study area included all major inland waters of Southeast Alaska.

Methods Between 1991 and 2007, cetacean surveys were conducted by observers who kept a constant watch when the vessel was underway and recorded all cetaceans encountered. For each species, we examined distributional patterns, group size, seasonal occurrence and annual trends. Analysis of variance (anova F) was used to test for differences in group sizes between multiple means, and Student’s t-test was used to detect differences between pairwise means. Cetacean seasonal occurrence and annual trends …

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Health Assessment Of Weddell Seals, Leptonychotes Weddellii, In Mcmurdo Sound, Antarctica, P.K. Yochem, B.S. Stewart, T.S. Gelatt, D.B. Siniff Jan 2009

Health Assessment Of Weddell Seals, Leptonychotes Weddellii, In Mcmurdo Sound, Antarctica, P.K. Yochem, B.S. Stewart, T.S. Gelatt, D.B. Siniff

United States Department of Commerce: Staff Publications

The demography of Weddell seals in eastern McMurdo Sound, Antarctica, has been well studied during the past three decades (e.g. Stirling 1971; Siniff et al. 1977; Testa and Siniff 1987; Hastings and Testa 1998; Gelatt et al. 2001). Detailed life-history data are available on thousands of seals tagged as pups in McMurdo Sound, making this population a rich resource for wildlife health studies because health parameters can be evaluated in the light of reproductive histories and genetic relationships of several generations of tagged seals.

Recently, evidence of exposure to diseases generally associated with domestic animals and feral wildlife has been …

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A Fish Of Many Scales: Extrapolating Sublethal Pesticide Exposures To The Productivity Of Wild Salmon Populations, David H. Baldwin, Julann A. Spromberg, Tracy K. Collier, Nathaniel L. Scholz Jan 2009

A Fish Of Many Scales: Extrapolating Sublethal Pesticide Exposures To The Productivity Of Wild Salmon Populations, David H. Baldwin, Julann A. Spromberg, Tracy K. Collier, Nathaniel L. Scholz

United States Department of Commerce: Staff Publications

For more than a decade, numerous pesticides have been detected in river systems of the western United States that support anadromous species of Pacific salmon and steelhead. Over the same interval, several declining wild salmon populations have been listed as either threatened or endangered under the U.S. Endangered Species Act (ESA). Because pesticides occur in surface waters that provide critical habitat for ESA-listed stocks, they are an ongoing concern for salmon conservation and recovery throughout California and the Pacific Northwest. Because pesticide exposures are typically sublethal, a key question is whether toxicological effects at (or below) the scale of the …

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Movements Of Satellite-Tagged Cuvier’S And Blainville’S Beaked Whales In Hawai‘I: Evidence For An Offshore Population Of Blainville’S Beaked Whales, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Sabre D. Mahaffy, Daniel J. Mcsweeney, M. Bradley Hanson, Russel D. Andrews Jan 2009

Movements Of Satellite-Tagged Cuvier’S And Blainville’S Beaked Whales In Hawai‘I: Evidence For An Offshore Population Of Blainville’S Beaked Whales, Robin W. Baird, Gregory S. Schorr, Daniel L. Webster, Sabre D. Mahaffy, Daniel J. Mcsweeney, M. Bradley Hanson, Russel D. Andrews

United States Department of Commerce: Staff Publications

The impacts of mid-frequency active sonar on the behavior of individual cetaceans may vary depending on their history of prior exposure. Evidence from habitat use, repeated sightings of identified individuals, and satellite tagging all indicate the existence of resident populations of Cuvier’s and Blainville’s beaked whales off the island of Hawai‘i, within the Navy’s Hawai‘i Range Complex. The number of individuals that have been satellite tagged is small however, and we are combining additional satellite tagging with individual photo-identification studies to assess movements and residency of both species. Field efforts were undertaken off the island of Hawai‘i in December 2008 …

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Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert Jan 2009

Relating Groundwater To Seasonal Wetlands In Southeastern Wisconsin, Usa, John D. Skalbeck, Donald M. Reed, Randall J. Hunt, Jamie D. Lambert

United States Geological Survey: Staff Publications

Historically, drier types of wetlands have been difficult to characterize and are not well researched. Nonetheless, they are considered to reflect the precipitation history with little, if any, regard for possible relation to groundwater. Two seasonal coastal wetland types (wet prairie, sedge meadow) were investigated during three growing seasons at three sites in the Lake Michigan Basin, Wisconsin, USA. The six seasonal wetlands were characterized using standard soil and vegetation techniques and groundwater measurements from the shallow and deep systems. They all met wetland hydrology criteria (e.g., water within 30 cm of land surface for 5% of the growing season) …

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Chapter 13: Space- And Ground-Based Studies Of Lightning Signatures, Timothy Hamlin, Kyle Wiens, Abram Jacobson, Tracey E. L. Light, Kenneth B. Eack Jan 2009

Chapter 13: Space- And Ground-Based Studies Of Lightning Signatures, Timothy Hamlin, Kyle Wiens, Abram Jacobson, Tracey E. L. Light, Kenneth B. Eack

Department of Earth and Atmospheric Sciences: Faculty Publications

This article provides a brief survey of the space- and ground-based studies of lightning performed by investigators at Los Alamos National Laboratory (LANL). The primary goal of these studies was to further understand unique lightning signatures known as Narrow Bipolar Events (NBEs). First, an overview is presented of the Fast On-orbit Recording of Transient Events (FORTE) satellite and of the ground-based Los Alamos Sferic Array (LASA). This is followed by a summary of the phenomenology, physics, and meteorological context of NBEs and NBE-related discharges. This article also discusses additional radio frequency and optical observations of lightning made by the FORTE …

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Radon - Repair And Diagnosis In Ontology Networks, Qiu Ji, Peter Haase, Guilin Qi, Pascal Hitzler, Steffen Stadtmuller Jan 2009

Radon - Repair And Diagnosis In Ontology Networks, Qiu Ji, Peter Haase, Guilin Qi, Pascal Hitzler, Steffen Stadtmuller

Computer Science and Engineering Faculty Publications

One of the major challenges in managing networked and dynamic ontologies is to handle inconsistencies in single ontologies, and inconsistencies introduced by integrating multiple distributed ontologies. Our RaDON system provides functionalities to repair and diagnose ontology networks by extending the capabilities of existing reasoners. The system integrates several new debugging and repairing algorithms, such as a relevance-directed algorithm to meet the various needs of the users.

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Analysis Of Connections Between Pseudocodewords, Nathan Axvig, Deanna Dreher, Katherine Morrison, Eric T. Psota, Lance C. Pérez, Judy L. Walker Jan 2009

Analysis Of Connections Between Pseudocodewords, Nathan Axvig, Deanna Dreher, Katherine Morrison, Eric T. Psota, Lance C. Pérez, Judy L. Walker

Department of Mathematics: Faculty Publications

The role of pseudocodewords in causing noncodeword outputs in linear programming (LP) decoding, graph cover decoding, and iterative message-passing decoding is investigated. The three main types of pseudocodewords in the literature — linear programming pseudocodewords, graph cover pseudocodewords, and computation tree pseudocodewords — are reviewed and connections between them are explored. Some discrepancies in the literature on minimal and irreducible pseudocodewords are highlighted and clarified, and a value for the minimal degree cover necessary to realize an LP pseudocodeword is found. Additionally, some conditions for the existence of connected realizations of graph cover pseudocodewords are given. This allows for further …

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Dispersal And Establishment Both Limit Colonization During Primary Succession On A Glacier Foreland, Chad C. Jones, Roger Del Moral Jan 2009

Dispersal And Establishment Both Limit Colonization During Primary Succession On A Glacier Foreland, Chad C. Jones, Roger Del Moral

Botany Faculty Publications

Plant colonization can be limited by lack of seeds or by factors that reduce establishment. The role of seed limitation in community assembly is being increasingly recognized, but in early primary succession, establishment failure is still considered more important. We studied the factors limiting colonization on the foreland of Coleman Glacier, Washington, USA to determine the importance of seed and establishment limitation during primary succession. We also evaluated the effects of seed predation, drought and existing vegetation on establishment. We planted seeds of seven species into plots of four different ages and found evidence that both seed and establishment limitation …

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The Erdős-Lovász Tihany Conjecture For Quasi-Line Graphs, J. Balogh, A. V. Kostochka, N. Prince, M. Stiebitz Jan 2009

The Erdős-Lovász Tihany Conjecture For Quasi-Line Graphs, J. Balogh, A. V. Kostochka, N. Prince, M. Stiebitz

Faculty Publications & Research

Erdős and Lovász conjectured in 1968 that for every graph G with χ(G) > ω(G) and any two integers s, t ≥ 2 with s + t = χ(G) + 1, there is a partition (S,T) of the vertex set V(G) such that χ(G[S]) ≥ s and χ(G[T]) ≥ t . Except for a few cases, this conjecture is still unsolved. In this note we prove the conjecture for quasi-line graphs and for graphs with independence number 2.

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Extremal Problems For Roman Domination, E. W. Chambers, W. Kinnersley, N. Prince, D. B. West Jan 2009

Extremal Problems For Roman Domination, E. W. Chambers, W. Kinnersley, N. Prince, D. B. West

Faculty Publications & Research

A Roman dominating function of a graph G is a labeling f: V(G) →{0,1,2} such that every vertex with a label 0 has a neighbor with label 2. The Roman domination number γR(G) of G is the minimum of ∑ʋϵV(G)f(v) over such functions. Let G be a connected n-vertex graph. We prove that γR(G) ≤ 4n/5, and we characterize the graphs achieving equality. We obtain sharp upper and lower bounds for γR(G) + …

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Electrical Measurements Of The Polarization In A Moving Magnetic Vortex, Jun-Ichiro Ohe, Stewart E. Barnes, Hyun-Woo Lee, Sadamichi Maekawa Jan 2009

Electrical Measurements Of The Polarization In A Moving Magnetic Vortex, Jun-Ichiro Ohe, Stewart E. Barnes, Hyun-Woo Lee, Sadamichi Maekawa

Physics Articles and Papers

We propose that the polarization of the moving magnetic vortex core can be detected by the electro- and spin-motive forces acting on the spin-polarized conduction electrons. With parameters appropriate to Permalloy, we have simulated the dynamics of a magnetic vortex core resulting from an applied oscillating magnetic field. We show that the polarization of the moving core can be detected by a simple electrical measurement.

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East Bay Energy Consortium In Partnership With Roger Williams University : Executive Summary Jan 2009

East Bay Energy Consortium In Partnership With Roger Williams University : Executive Summary

East Bay Energy Consortium Documents

No abstract provided.

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Town Of Bristol Wind Feasibility Studies Jan 2009

Town Of Bristol Wind Feasibility Studies

East Bay Energy Consortium Documents

No abstract provided.

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Wind Energy Conversion Systems : Revised Draft Jan 2009

Wind Energy Conversion Systems : Revised Draft

East Bay Energy Consortium Documents

No abstract provided.

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Town Of Bristol Wind Referendum Jan 2009

Town Of Bristol Wind Referendum

East Bay Energy Consortium Documents

No abstract provided.

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Roger Williams University Commitment Letter Jan 2009

Roger Williams University Commitment Letter

East Bay Energy Consortium Documents

No abstract provided.

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Rwu Law School Marine Affairs Institute Proposal Jan 2009

Rwu Law School Marine Affairs Institute Proposal

East Bay Energy Consortium Documents

No abstract provided.

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East Bay Energy Consortium Wind Velocity Jan 2009

East Bay Energy Consortium Wind Velocity

East Bay Energy Consortium Documents

No abstract provided.

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Bristol And Portsmouth Informed Opinion Wind Survey Jan 2009

Bristol And Portsmouth Informed Opinion Wind Survey

East Bay Energy Consortium Documents

No abstract provided.

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Rhode Island Renewable Energy Fund Application Materials Jan 2009

Rhode Island Renewable Energy Fund Application Materials

East Bay Energy Consortium Documents

No abstract provided.

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