Direct-coupled microcomputer-based building emulator for building energy management and control systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lam, H.N.

1999-07-01

In this paper, the development and implementation of a direct-coupled building emulator for a building energy management and control system (EMCS) is presented. The building emulator consists of a microcomputer and a computer model of an air-conditioning system implemented in a modular dynamic simulation software package for direct-coupling to an EMCS, without using analog-to-digital and digital-to-analog converters. The building emulator can be used to simulate in real time the behavior of the air-conditioning system under a given operating environment and subject to a given usage pattern. Software modules for data communication, graphical display, dynamic data exchange, and synchronization of simulationmore » outputs with real time have been developed to achieve direct digital data transfer between the building emulator and a commercial EMCS. Based on the tests conducted, the validity of the building emulator has been established and the proportional-plus-integral control function of the EMCS assessed.« less

Kirtland's Warbler (Setophaga kirtlankii)

Treesearch

John R. Probst; Deahn M. Donner

2011-01-01

Spring travelers from around the world are attracted to the young jack pine forests of Michigan for a chance to hear the loud distinct song of the endangered Kirtland's Warbler. This blue-gray-backed warbler with a yellow underside can be heard singing from its perch in the tops of standing snags or jack pine trees, or seen hopping from tree to tree or to the...

Population increase in Kirtland's warbler and summer range expansion to Wisconsin and Michigan's Upper Peninsula, USA

Treesearch

John R. Probst; Deahn M. Donner; Carol I. Bocetti; Steve Sjogren

2003-01-01

The threatened Kirtland's warbler Dendroica kirtlandii breeds in stands of young jack pine Pinus banksiana growing on well-drained soils in Michigan, USA. We summarize information documenting the range expansion of Kirtland's warbler due to increased habitat management in the core breeding range in the Lower Peninsula of...

Adaptive forest management to improve habitats for cerulean warbler

Treesearch

Paul B. Hamel

2006-01-01

Cerulean Warbler (Dendroica cerulea, Aves: Parulidae) is a Neotropical migratory bird with a declining population. These birds are a focal species of the U.S. Fish and Wildlife Service, and listed as Vulnerable to Extinction by the International Union for the Conservation of Nature. Thus, the birds properly may be considered to be a conservation...

Population increase in Kirtland's warbler and summer range expansion to Wisconsin and Michigan's Upper Peninsula, USA

Treesearch

John R. Probst; Deahn Donner; Carol I. Bocetti; Steve Sjogren

2003-01-01

The threatened Kirtland`s warbler Dendroica kirtlandii breeds in stands of young jack pine Pinus banksiana growing on well-drained soils in Michigan, USA. We summarize information documenting the range expansion of Kirtland`s warbler due to increased habitat management in the core breeding range in the Lower Peninsula of Michigan...

Arthropod prey of Wilson's Warblers in the understory of Douglas-fir forests

USGS Publications Warehouse

Hagar, J.C.; Dugger, K.M.; Starkey, E.E.

2007-01-01

Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

Kirtland's warbler diet as determined through fecal analysis

USGS Publications Warehouse

Deloria-Sheffield, Christie M.; Millenbah, Kelly F.; Bocetti, Carol I.; Sykes, P.W.; Kepler, C.B.

2001-01-01

The endangered Kirtland's Warbler (Dendroica kirtlandii) nests primarily in large (>32 ha) stands of young (5- to 25-yr-old) jack pine (Pinus banksiana) which grow on Grayling sand soil. These specific habitat requirements restrict the Kirtland's Warbler breeding range to only 13-16 counties in the northern lower peninsula of Michigan. Although the nature of the species' affinity for this habitat is poorly understood, one theory suggests that higher prey abundance in young jack pine may play a role. To explore further the hypothesis that Kirtland's Warblers choose nesting habitat due to prey abundance, a more thorough knowledge of the warblers' diet is needed. To better understand the diet, we identified arthropod and plant fragments found in 202 Kirtland's Warbler fecal samples, collected from June to September, 1995-1997. The major food items recorded were spittlebugs and aphids (Homoptera; found in 61% of all samples), ants and wasps (Hymenoptera; 45%), blueberry (Vaccinium augustifolium; 42%), beetles (Coleoptera; 25%), and moth larvae (Lepidoptera; 22%).

An orbital emulator for pursuit-evasion game theoretic sensor management

NASA Astrophysics Data System (ADS)

Shen, Dan; Wang, Tao; Wang, Gang; Jia, Bin; Wang, Zhonghai; Chen, Genshe; Blasch, Erik; Pham, Khanh

2017-05-01

This paper develops and evaluates an orbital emulator (OE) for space situational awareness (SSA). The OE can produce 3D satellite movements using capabilities generated from omni-wheeled robot and robotic arm motion methods. The 3D motion of a satellite is partitioned into the movements in the equatorial plane and the up-down motions in the vertical plane. The 3D actions are emulated by omni-wheeled robot models while the up-down motions are performed by a stepped-motor-controlled-ball along a rod (robotic arm), which is attached to the robot. For multiple satellites, a fast map-merging algorithm is integrated into the robot operating system (ROS) and simultaneous localization and mapping (SLAM) routines to locate the multiple robots in the scene. The OE is used to demonstrate a pursuit-evasion (PE) game theoretic sensor management algorithm, which models conflicts between a space-based-visible (SBV) satellite (as pursuer) and a geosynchronous (GEO) satellite (as evader). The cost function of the PE game is based on the informational entropy of the SBV-tracking-GEO scenario. GEO can maneuver using a continuous and low thruster. The hard-in-loop space emulator visually illustrates the SSA problem solution based PE game.

Refined conservation strategies for Golden-winged Warblers in the West Virginia highlands with implications for the broader avian community

USGS Publications Warehouse

Aldinger, Kyle R.; Wood, Petra B.; Johnson, Catherine M.

2017-01-01

Golden-winged Warbler (Vermivora chrysoptera) populations in the Appalachian Mountains region of North America are imperiled, warranting species-specific conservation. However, management for Golden-winged Warblers can affect both early-successional and forest species, many of which are also declining in the region. We conducted point counts in sites representing a range of successional stages within the Golden-winged Warbler's breeding range in West Virginia, USA, during 2008–2015. We identified plausible models of Golden-winged Warbler density using covariates at 4 spatial scales representing annual dispersal (5-km radius), extraterritorial movement (1.5-km radius), intraterritorial movement (100-m radius), and local resource utilization (11.3-m radius). Golden-winged Warbler density peaked at an intermediate elevation at the 1.5-km radius scale, but was negatively associated with 100-m radius minimum elevation. Density was positively associated with 100-m radius shrubland cover. Southerly latitudes were associated with higher densities when modeled alone, but there was no association when controlling for other covariates. We then examined the relationship between covariates from these plausible models and avian community structure using canonical correspondence analysis to assess the value of Golden-winged Warbler conservation for the broader avian community. We identified 5 species likely to benefit from management for Golden-winged Warblers and 21 species likely to be affected positively or negatively to varying degrees depending on their affinity for early-successional vegetation communities. Golden-winged Warblers were plotted higher along the 100-m shrubland cover gradient than any other bird species, suggesting that they may be the most shrubland area–sensitive songbird in our study area. However, the species also requires heavily forested landscapes. Therefore, a species-specific conservation strategy that balances shrubland (patches of 9–13 ha in

Incidence of nest material kleptoparasitism invlovling cerulean warblers

Treesearch

Kelly C. Jones; Kirk L. Roth; Kamal Islam; Paul B. Hamel; Carl G. III Smith

2007-01-01

document 21 observations of interspecific stealing of nesting material involving Cerulean Warblers (Dendroica cerulea), Red-eyed Vireos (Vireo olivaceus/i>), Blue-gray Gnatcatchers (Polioptila caerulea/i>), Northern Parulas (Parula americana/i>), Black-throated Green Warblers (D. virens), American Redstarts (

Shifting foundations and metrics for golden-cheeked warbler recovery

USGS Publications Warehouse

Hatfield, Jeff S.; Weckerly, Floyd W.; Duarte, Adam

2012-01-01

Using the golden-cheeked warbler (Setophaga chrysoparia) as a case study, this paper discusses what lessons can be learned from the process of the emergency listing and subsequent development of the recovery plan. Are the metrics for recovery in the current warbler plan appropriate, including population size and distribution (recovery units), migration corridors, and wintering habitat? In other words, what happened, what can we learn, and what should happen (in general) in the future for development of such plans? We discuss the number of recovery units required for species persistence and estimate the number of male warblers in protected areas across the breeding range of the species, using newly published density estimates. We also discuss future monitoring strategies to estimate warbler population trends and dispersal rates.

Influence of habitat amount, arrangement, and use on population trend estimates of male Kirtland's warblers

USGS Publications Warehouse

Donner, D.M.; Probst, J.R.; Ribic, C.A.

2008-01-01

Kirtland's warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5-23 years old) created after wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and wildfire disturbances influenced population size and spatial dispersion of male Kirtland's warblers within their restricted breeding range in northern Lower Michigan, USA. The male Kirtland's warbler population was six times larger in 2004 (1,322) compared to 1979 (205); the change was nonlinear with 1987 and 1994 identified as significant points of change. In 1987, the population trend began increasing after a slowly declining trend prior to 1987, and the rate of increase appeared to slow after 1994. Total amount of suitable habitat and the relative area of wildfire-regenerated habitat were the most important factors explaining population trend. Suitable habitat increased 149% primarily due to increasing plantations from forest management. The relative amount and location of wildfire-regenerated habitat modified the distribution of males among various habitat types, and the spatial variation in their abundance across the primary breeding range. These findings indicate that the Kirtland's warbler male population shifted its use of habitat types temporally and spatially as the population increased and as the relative availability of habitats changed through time. We demonstrate that researchers and managers need to consider not only habitat quality, but the temporal and the spatial context of habitat availability and population levels when making habitat restoration decisions. ?? 2008 Springer Science+Business Media B.V.

Song and Male Quality in Prairie Warblers

Treesearch

Bruce E. Byers; Michael E. Akresh; David I. King; W. Koenig

2016-01-01

To determine if the songs of male prairie warblers could potentially reveal to female listeners information about the quality of singers, we compared various aspects of prairie warbler song structure and performance to attributes that might reflect a male singer's potential to enhance the fitness of his mate. We found that all the tested male attributes—arrival...

Variables associated with nest survival of Golden-winged Warblers (Vermivora chrysoptera) among vegetation communities commonly used for nesting

USGS Publications Warehouse

Aldinger, Kyle R.; Terhune, Theron M.; Wood, Petra Bohall; Buehler, David A.; Bakermans, Marja H.; Confer,  John L.; Flaspohler, David J.; Larkin, Jeffrey L.; Loegering, John P.; Percy, Katie L.; Roth, Amber M.; Smalling, Curtis G.

2015-01-01

Among shrubland- and young forest-nesting bird species in North America, Golden-winged Warblers (Vermivora chrysoptera) are one of the most rapidly declining partly because of limited nesting habitat. Creation and management of high quality vegetation communities used for nesting are needed to reduce declines. Thus, we examined whether common characteristics could be managed across much of the Golden-winged Warbler’s breeding range to increase daily survival rate (DSR) of nests. We monitored 388 nests on 62 sites throughout Minnesota, Wisconsin, New York, North Carolina, Pennsylvania, Tennessee, and West Virginia. We evaluated competing DSR models in spatial-temporal (dominant vegetation type, population segment, state, and year), intraseasonal (nest stage and time-within-season), and vegetation model suites. The best-supported DSR models among the three model suites suggested potential associations between daily survival rate of nests and state, time-within-season, percent grass and Rubus cover within 1 m of the nest, and distance to later successional forest edge. Overall, grass cover (negative association with DSR above 50%) and Rubus cover (DSR lowest at about 30%) within 1 m of the nest and distance to later successional forest edge (negative association with DSR) may represent common management targets across our states for increasing Golden-winged Warbler DSR, particularly in the Appalachian Mountains population segment. Context-specific adjustments to management strategies, such as in wetlands or areas of overlap with Blue-winged Warblers (Vermivora cyanoptera), may be necessary to increase DSR for Golden-winged Warblers.

Diet of Wilson's warblers and distribution of arthropod prey in the understory of Douglas-fir forests

USGS Publications Warehouse

Hagar, Joan C.; Dugger, Kate; Starkey, Edward E.

2007-01-01

Availability of food resources is an important factor in avian habitat selection. Food resources for terrestrial birds often are closely related to vegetation structure and composition. Identification of plant species important in supporting food resources may facilitate vegetation management to achieve objectives for providing bird habitat. We used fecal analysis to describe the diet of adult Wilson's Warblers (Wilsonia pusilla) that foraged in the understory of Douglas-fir (Pseudotsuga menziesii) forests in western Oregon during the breeding season. We sampled arthropods at the same sites where diet data were collected, and compared abundance and biomass of prey among seven common shrub species. Wilson's Warblers ate more caterpillars (Lepidoptera larvae), flies (Diptera), beetles (Coleoptera), and Homoptera than expected based on availability. Deciduous shrubs supported higher abundances of arthropod taxa and size classes used as prey by Wilson's Warblers than did evergreen shrubs. The development and maintenance of deciduous understory vegetation in conifer forests of the Pacific Northwest may be fundamental for conservation of food webs that support breeding Wilson's Warblers and other shrub-associated, insectivorous songbirds.

Hooded warbler in North Dakota

USGS Publications Warehouse

Hotchkiss, N.

1943-01-01

he 1942 warbler migration at Kenmare, Ward County, North Dakota, was rich in species (seventeen) for a locality so far west on the Great Plains. On June 1, near the end of the northward flight, I found a male Hooded Warbler singing in shrubby undergrowth on a wooded coulee slope on the Des Lacs National Wildlife Refuge, about two miles south of Kenmare. The bird was observed at close range for several minutes, both without and with 7-power binoculars. It behaved as in the vicinity of Washington, D. C., where I have been familiar with the species for several years, the song being vigorous and loud and the movements leisurely.

Nonbreeding isolation and population-specific migration patterns among three populations of Golden-winged Warblers

USGS Publications Warehouse

Kramer, Gunnar R.; Streby, Henry M.; Peterson, Sean M.; Lehman, Justin A.; Buehler, David A.; Wood, Petra B.; McNeil, Darin J.; Larkin, Jeffrey L.; Andersen, David E.

2017-01-01

Golden-winged Warblers (Vermivora chrysoptera) are Nearctic–Neotropical migrants experiencing varied regional population trends not fully explained by breeding-grounds factors such as nest success. A lack of detailed information on the nonbreeding distributions, migration routes, or timing of migration among populations hampers our ability to identify population processes outside the breeding period. We used geolocators to track annual movements of 21 Golden-winged Warblers from 3 North American breeding locations experiencing varying population trends to investigate the potential for nonbreeding site factors to influence breeding populations. We used the template-fit method to estimate locations of individual warblers throughout the year. Geolocator-marked warblers exhibited significant isolation among populations during migration and the nonbreeding period. During the nonbreeding period, Golden-winged Warblers from Minnesota, USA (n = 12) occurred in Central America from southern Mexico to central Nicaragua; warblers from Tennessee, USA (n = 7) occurred along the border of northern Colombia and Venezuela; and warblers from Pennsylvania, USA (n = 2) occurred in north-central Venezuela. Warblers travelled at slower rates over more days in fall migration than spring migration. Fall migration routes at the Gulf of Mexico were population-specific, whereas spring routes were more varied and overlapped among populations. Golden-winged Warblers from Pennsylvania migrated 4,000 and 5,000 km yr−1 farther than Tennessee and Minnesota warblers, respectively, and spent almost twice as long migrating in the fall compared to Minnesota warblers. Our results reveal nearly complete temporal and geographic isolation among 3 populations of Golden-winged Warblers throughout the annual cycle, resulting in opportunities for population- and site-specific factors to differentially influence populations outside the breeding period. Our findings highlight the need for monitoring

Uncertainty-based simulation-optimization using Gaussian process emulation: Application to coastal groundwater management

NASA Astrophysics Data System (ADS)

Rajabi, Mohammad Mahdi; Ketabchi, Hamed

2017-12-01

Combined simulation-optimization (S/O) schemes have long been recognized as a valuable tool in coastal groundwater management (CGM). However, previous applications have mostly relied on deterministic seawater intrusion (SWI) simulations. This is a questionable simplification, knowing that SWI models are inevitably prone to epistemic and aleatory uncertainty, and hence a management strategy obtained through S/O without consideration of uncertainty may result in significantly different real-world outcomes than expected. However, two key issues have hindered the use of uncertainty-based S/O schemes in CGM, which are addressed in this paper. The first issue is how to solve the computational challenges resulting from the need to perform massive numbers of simulations. The second issue is how the management problem is formulated in presence of uncertainty. We propose the use of Gaussian process (GP) emulation as a valuable tool in solving the computational challenges of uncertainty-based S/O in CGM. We apply GP emulation to the case study of Kish Island (located in the Persian Gulf) using an uncertainty-based S/O algorithm which relies on continuous ant colony optimization and Monte Carlo simulation. In doing so, we show that GP emulation can provide an acceptable level of accuracy, with no bias and low statistical dispersion, while tremendously reducing the computational time. Moreover, five new formulations for uncertainty-based S/O are presented based on concepts such as energy distances, prediction intervals and probabilities of SWI occurrence. We analyze the proposed formulations with respect to their resulting optimized solutions, the sensitivity of the solutions to the intended reliability levels, and the variations resulting from repeated optimization runs.

How we can learn more about the Cerulean Warbler (Dendroica cerulea)

USGS Publications Warehouse

Hamel, P.B.; Dawson, D.K.; Keyser, P.D.

2004-01-01

A sense of urgency attends the study of species of concern, like the Cerulean Warbler (Dendroica cerulea). Sharpened by Robbins et al. (1992) and Hamel (1992), such concern prompted the U.S. Department of the Interior, Fish and Wildlife Service (USFWS) to commission a status assessment of the Cerulean Warbler (Hamel 2000a). Shortly after the status review was published, a petition (Ruley 2000) was delivered to the USFWS urging that the species be listed as “threatened” under the Endangered Species Act of 1973. The account of the Cerulean Warbler in the Birds of North America series also appeared that year (Hamel 2000b). Substantial attention is currently focused on the species, and the Cerulean Warbler Technical Group (CWTG) was formed in 2002 (see Appendix).This overview consists of two parts. The first, prepared primarily by P.B.H., attempts to summarize current knowledge and suggest productive avenues to pursue in our efforts to understand the biology and conserve populations of Cerulean Warblers. The second, written by D.K.D. and P.D.K., is a summary of the structure and priorities of the CWTG, an organization that can spur and facilitate research and conservation action directed at this species and serve as a model for conservation of other forest birds (Appendix). Further information on Cerulean Warblers and activities of the Cerulean Warbler Technical Group can be found on the CWTG website (see Acknowledgments).

Density-dependent mass gain by Wilson's Warblers during stopover

Treesearch

Jeffrey F. Kelly; Linda S. DeLay; Deborah M. Finch

2002-01-01

The need restore energetic reserves at stopover sites constrains avian migration ecology. To describe that constraint, we examined relationships among mass gained by Wilson's Warblers (Wilsonia pusilla) during stopover, abundance of Wilson's Warblers (i.e. capture rate), and arthropod abundance during autumn migration. We found that amount...

Age-Ratios and Condition of En Route Migrant Blackpoll Warblers in the British Virgin Islands

USGS Publications Warehouse

Boal, Clint W.

2014-01-01

The en route migration ecology of Blackpoll Warblers (Setophaga striata) is poorly understood, yet intriguing. Blackpoll Warblers undertake the longest open water migration of any wood warbler species, traveling from northeastern North America to South America, with the first potential landfall being the West Indies. This migration requires substantial energy reserves and subjects Blackpoll Warblers to unpredictable weather events, which may influence survival. Few studies have examined age ratios or condition of Blackpoll Warblers while the warblers are en route through the Caribbean region. I captured and banded Blackpoll Warblers in the British Virgin Islands over 10 consecutive autumn migrations. Ratios of hatch-year to adult Blackpoll Warblers were variable but averaged lower than the ratios reported at continental departure locations. Average mass of Blackpoll Warblers was less than that reported at continental departure locations, with 26% of adults and 40% of hatch-year birds below the estimated fat free mass; hatch-year birds were consistently in poorer condition than adults. Blackpoll Warblers captured in the British Virgin Islands were also in poorer condition than those reported from the Dominican Republic and Barbados; this may be because of the British Virgin Islands being the first landfall after the transatlantic crossing, whereas Blackpoll Warblers arriving at the other Caribbean study locations may have had opportunities for stopover prior to arrival or have departed from farther south on the continent. However, this suggests that the British Virgin Islands likely provide important stopover habitat as a first landfall location for Blackpoll Warblers arriving from the transatlantic migration route.

Predicting cerulean warbler habitat use in the Cumberland Mountains of Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buehler, D.A.; Welton, M.J.; Beachy, T.A.

2006-12-15

We developed a habitat model to predict cerulean warbler (Dendroica cerulea) habitat availability in the Cumberland Mountains of eastern Tennessee. We used 7 remotely sensed vegetation and topographic landform explanatory variables and known locations of territorial male cerulean warblers mapped in 2003 as the response variable to develop a Mahalanobis distance statistic model of potential habitat. We evaluated the accuracy of the model based on field surveys for ceruleans during the 2004 breeding season. The model performed well with an 80% correct classification of cerulean presence based on the validation data, although prediction of absence was only 54% correct. Wemore » extrapolated from potential habitat to cerulean abundance based on density estimates from territory mapping on 8 20-ha plots in 2005. Over the 200,000-ha study area, we estimated there were 80,584 ha of potential habitat, capable of supporting about 36,500 breeding pairs. We applied the model to the 21,609-ha state-owned Royal Blue Wildlife Management Area to evaluate the potential effects of coal surface mining as one example of a potential conflict between land use and cerulean warbler conservation. Our models suggest coal surface mining could remove 2,954 ha of cerulean habitat on Royal Blue Wildlife Management Area and could displace 2,540 breeding pairs (23% of the Royal Blue population). A comprehensive conservation strategy is needed to address potential and realized habitat loss and degradation on the breeding grounds, during migration, and on the wintering grounds.« less

Scalable and reusable emulator for evaluating the performance of SS7 networks

NASA Astrophysics Data System (ADS)

Lazar, Aurel A.; Tseng, Kent H.; Lim, Koon Seng; Choe, Winston

1994-04-01

A scalable and reusable emulator was designed and implemented for studying the behavior of SS7 networks. The emulator design was largely based on public domain software. It was developed on top of an environment supported by PVM, the Parallel Virtual Machine, and managed by OSIMIS-the OSI Management Information Service platform. The emulator runs on top of a commercially available ATM LAN interconnecting engineering workstations. As a case study for evaluating the emulator, the behavior of the Singapore National SS7 Network under fault and unbalanced loading conditions was investigated.

Wilson's warbler in Maryland in late December

USGS Publications Warehouse

Robbins, C.S.

1949-01-01

On December 22, 1947, while participating in a Christmas Bird Count on the eastern shore of Maryland, I observed a Wilson's warbler (Wilsonia pusilla) feeding along a sunny margin of a woods near the Pocomoke River, three miles north of Snow Hill. It was with a flock of myrtle warblers (Dendroica coronata), white-throated sparrows (Zonotrichia albicollis), Carolina chickadees (Parus carolinensis), and several other species. My attention was first attracted to the Wilson's warbler by the distinctive call note which it repeated about once a minute. The bird was actively feeding among the dead leaves on a group of young oak trees. The bird was collected and proved to be a female. The skin was preserved for the collection of the Fish and Wildlife Service. The stomach was full, and the contents were identified by Robert T. Mitchell as: fragments of Araneida, 80 per cent; Coleoptera, 10 per cent; Hymenoptera, 10 per cent.

Initial cerulean warbler response to experimental silvicultural manipulations, Desha County, Arkansas

Treesearch

Paul B. Hamel; Mike Staten; Rodney Wishard

2006-01-01

Cerulean warbler [Dendroica cerulea (Wilson) Aves, Parulidae] is a neotropical migratory bird that has become a focus of management attention. Since 1992, we have studied breeding birds on a 54-ha site owned by Anderson-Tully Company, in Desha County, AR. In 2002, we conducted an unreplicated experiment there to assess the species’ response to...

Breeding biology of Lucy's Warbler in southwestern New Mexico

Treesearch

Scott H. Stoleson; Roland S. Shook; Deborah M. Finch

2000-01-01

We found Lucy's Warblers breeding abundantly in mid-elevation broadleaf riparian forests in the lower Gila River valley of southwestern New Mexico. They arrived en masse in the third week of March. Patterns of singing suggested that Lucy's Warblers might raise two broods. Few were heard or seen after late July. Estimated population densities ranged from 1. 7...

Landsat TM as a Tool for Locating Habitat for Cerulean Warblers

NASA Technical Reports Server (NTRS)

Kellner, Chris

2000-01-01

I believe that I made significant strides in three areas between fall of 1997 and fall of 2000 when I concluded my participation in the JOVE program. First, I acquired skill in digital remote sensing. This was significant to me because it had been 20 years since I had done any work utilizing remote sensing. I used my new skills in two classroom settings (forest ecology and GIS). In addition, I will participate as an instructor of digital remote sensing in a workshop for secondary educators this coming spring. Second, I received funding from the Arkansas Game and Fish Commission and the U.S. Forest Service to supplement JOVE funds. Third, and most importantly, a students and I developed a technique using LandSAT TM for identifying habitat for cerulean warblers. We developed a habitat model using logistic regression to discriminate between pixels that had a high probability of representing good cerulean warbler habitat and pixels that had a low probability of representing cerulean warbler habitat. Using this model, we located five significant populations of cerulean warblers in the Ozark National Forest of Arkansas. These populations were unknown before the initiation of this research and further represent a significant proportion of the known cerulean warblers in Arkansas. Preliminary findings were presented at the Ornithological Societies of America meeting in August of 1999. I also presented findings at the Arkansas Game and Fish Commission Research Symposium held in June of 2000. Finally, one paper is in press: James, D. A., C.J. Kellner, J. Self, and J. Davis., 'Breeding season distribution of cerulean warblers in Arkansas in the 1990's'. In addition, one paper is under construction: 'Population fluctuation and habitat selection by cerulean warblers in upland forests of Arkansas,' and one paper is under consideration: 'LandSAT TM and Logistic regression for identification of cerulean warbler habitat in upland forests of Arkansas.'

Geolocator reveals migratory and winter movements of a Prothonotary Warbler

Treesearch

Jared D. Wolfe; Erik I. Johnson

2015-01-01

Prothonotary Warblers (Protonotaria citrea) are Nearctic-Neotropic migrants that have experienced declining populations over the past 50 yr. Determining their migration routes and wintering areas are critical steps in identifying habitats used by species and populations of conservation concern. We captured a male Prothonotary Warbler on its...

An intergeneric hybrid wood warbler (Seiurus x Dendroica)

USGS Publications Warehouse

Short, L.L.; Robbins, Chandler S.

1967-01-01

Wild hybrid birds are always of interest with regard to our understanding of the variation encountered in nature. They may also be of ore or less taxonomic significance, depending on the frequency of their occurrence and other factors. We herein report and describe an apparent hybrid Northern Waterthrush (Seiurus noveboracensis) x Blackpoll Warbler (Dendroica striata) taken by Robbins at Ocean City, Maryland, on 17 September 1965. The bird (U.S. National Museum, no. 481595), an immature male with no fat, weighed 13.7 g and had apparently normal testes, each measuring 2.0 x 0.5 mm. The hybrid was taken in a net situated close to the ground, inland from the beach north of Ocean City; both Northern Waterthrushes and Blackpoll Warblers were caught the same day in the same net.The hybrid has the general appearance of a large, dark, immature wood warbler of the genus Dendroica. It shows a peculiar color pattern – it is streaked on its breast somewhat like a Cape May Warbler (D. tigrine), is dark olive with indistinct streaks on its back, and has distinct buffy superciliary stripes, narrowly barred wings, a yellowish white abdomen, long white under tail coverts, and an almost unmarked dark tail. The specimen resembles a Blackpoll Warbler in the length of its wings, tail, and bill, but it has longer legs and toes than members of that species.We are indebted to Mrs. Roxie C. Laybourne, David Bridge, and Paul Slud for useful suggestions, and to Kenneth C. Parkes for a helpful reading of the manuscript. The birds were banded at the Operation Recovery banding station by Robbins, Mrs. Richard D. Cole, Mrs. Herbert M. Church, William S. Clark, Mr. and Mrs. Herman F. Kuch, and Mr. and Mrs. Aldridge pepper.

78 FR 68370 - Endangered and Threatened Wildlife and Plants; Technical Corrections for Kirtland's Warbler

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-14

... Corrections for Kirtland's Warbler AGENCY: Fish and Wildlife Service, Interior. ACTION: Direct final rule... (Kirtland's warbler) under the Endangered Species Act of 1973, as amended (Act). We are revising the List of... documents a taxonomic change (scientific name) to Kirtland's warbler (50 CFR 17.11(h)). The basis for the...

Avian community and microhabitat associations of Cerulean Warblers in Alabama

Treesearch

John P. Carpenter; Yong Wang; Callie Schweitzer; Paul B. Hamel

2011-01-01

Cerulean Warblers (Dendroica cerulea) have experienced one of the highest population declines of any neotropical-Nearctic migratory species in North America. We performed point counts and habitat assessments in areas used and unused by Cerulean Warblers in northern Alabama during the 2005 and 2006 breeding seasons to examine their avian associations and identify...

Understanding Survival And Abundance Of Overwintering Warblers: Does Rainfall Matter?

Treesearch

Katie M. Dugger; John G Faaborg; Wayne J. Arendt; Keith A. Hobson

2004-01-01

We investigated relationships between warbler abundance and survival rates measured on a Puerto Rican wintering site and rainfall patterns measured on the wintering site and in regions where these warblers breed, as estimated using stable-isotope analysis (δD) of feathers collected from wintering birds. We banded birds using constant-effort mist netting...

A Prolog Emulator

NASA Technical Reports Server (NTRS)

Tick, Evan

1987-01-01

This note describes an efficient software emulator for the Warren Abstract Machine (WAM) Prolog architecture. The version of the WAM implemented is called Lcode. The Lcode emulator, written in C, executes the 'naive reverse' benchmark at 3900 LIPS. The emulator is one of a set of tools used to measure the memory-referencing characteristics and performance of Prolog programs. These tools include a compiler, assembler, and memory simulators. An overview of the Lcode architecture is given here, followed by a description and listing of the emulator code implementing each Lcode instruction. This note will be of special interest to those studying the WAM and its performance characteristics. In general, this note will be of interest to those creating efficient software emulators for abstract machine architectures.

A test of 3 models of Kirtland's warbler habitat suitability

Treesearch

Mark D. Nelson; Richard R. Buech

1996-01-01

We tested 3 models of Kirtland's warbler (Dendroica kirtlandii) habitat suitability during a period when we believe there was a surplus of good quality breeding habitat. A jack pine canopy-cover model was superior to 2 jack pine stem-density models in predicting Kirtland's warbler habitat use and non-use. Estimated density of birds in high...

Effect of mating status and time of day on Kirtland's warbler song rates

Treesearch

Jack P. Hayes; John R. Probst; Don Rakstad

1986-01-01

Knowledge of factors affecting song rates is important because biologists use song in estimating or monitoring bird populations. Perhaps for no other species have song censuses played such a major role in population assessment and management as for the Kirtland`s Warbler (Dendroica kirtlandiz). In 1951, this endangered songbird was first censused...

Using a full annual cycle model to evaluate long-term population viability of the conservation-reliant Kirtland's warbler after successful recovery

USGS Publications Warehouse

Brown, Donald J.; Ribic, Christine; Donner, Deahn M.; Nelson, Mark D.; Bocetti, Carol I.; Deloria-Sheffield, Christie M.

2017-01-01

Long-term management planning for conservation-reliant migratory songbirds is particularly challenging because habitat quality in different stages and geographic locations of the annual cycle can have direct and carry-over effects that influence the population dynamics. The Neotropical migratory songbird Kirtland's warbler Setophaga kirtlandii (Baird 1852) is listed as endangered under the U.S. Endangered Species Act and Near Threatened under the IUCN Red List. This conservation-reliant species is being considered for U.S. federal delisting because the species has surpassed the designated 1000 breeding pairs recovery threshold since 2001.To help inform the delisting decision and long-term management efforts, we developed a population simulation model for the Kirtland's warbler that incorporated both breeding and wintering grounds habitat dynamics, and projected population viability based on current environmental conditions and potential future management scenarios. Future management scenarios included the continuation of current management conditions, reduced productivity and carrying capacity due to the changes in habitat suitability from the creation of experimental jack pine Pinus banksiana (Lamb.) plantations, and reduced productivity from alteration of the brown-headed cowbird Molothrus ater (Boddaert 1783) removal programme.Linking wintering grounds precipitation to productivity improved the accuracy of the model for replicating past observed population dynamics. Our future simulations indicate that the Kirtland's warbler population is stable under two potential future management scenarios: (i) continuation of current management practices and (ii) spatially restricting cowbird removal to the core breeding area, assuming that cowbirds reduce productivity in the remaining patches by ≤41%. The additional future management scenarios we assessed resulted in population declines.Synthesis and applications. Our study indicates that the Kirtland's warbler population

A hierarchical spatial model of avian abundance with application to Cerulean Warblers

USGS Publications Warehouse

Thogmartin, Wayne E.; Sauer, John R.; Knutson, Melinda G.

2004-01-01

is counts, such as animal counts, activity (e.g.,nest) counts, or species richness. The most noteworthy practical application of this spatial modeling approach is the ability to map relative species abundance. The functional relationships that we elucidated for the Cerulean Warbler provide a basis for the development of management programs and may serve to focus management and monitoring on areas and habitat variables important to Cerulean Warblers.

El Grupo Cerúleo: Collaboration to assess nonbreeding range of Cerulean Warbler in South America

Treesearch

Gabriel Colorado; Paul Hamel; Amanda Rodewals; Wayne Thogmartin

2008-01-01

Cerulean Warbler (Dendroica cerulea. Parulidae) has been listed as a vulnerable species by the International Union for the Conservation of Nature because of recent population declines. An international, proactive approach to Cerulean Warbler conservation, the Cerulean Warbler Technical Group, was founded in 2001. One of its subcommittees, El Grupo...

Selection of forest canopy gaps by male Cerulean Warblers in West Virginia

USGS Publications Warehouse

Perkins, Kelly A.; Wood, Petra Bohall

2014-01-01

Forest openings, or canopy gaps, are an important resource for many forest songbirds, such as Cerulean Warblers (Setophaga cerulea). We examined canopy gap selection by this declining species to determine if male Cerulean Warblers selected particular sizes, vegetative heights, or types of gaps. We tested whether these parameters differed among territories, territory core areas, and randomly-placed sample plots. We used enhanced territory mapping techniques (burst sampling) to define habitat use within the territory. Canopy gap densities were higher within core areas of territories than within territories or random plots, indicating that Cerulean Warblers selected habitat within their territories with the highest gap densities. Selection of regenerating gaps with woody vegetation >12 m within the gap, and canopy heights >24 m surrounding the gap, occurred within territory core areas. These findings differed between two sites indicating that gap selection may vary based on forest structure. Differences were also found regarding the placement of territories with respect to gaps. Larger gaps, such as wildlife food plots, were located on the periphery of territories more often than other types and sizes of gaps, while smaller gaps, such as treefalls, were located within territory boundaries more often than expected. The creations of smaller canopy gaps, <100 m2, within dense stands are likely compatible with forest management for this species.

Conservation planning and accomplishments for protection of Cerulean Warbler (Setophaga cerulea) nonbreeding habitat

Treesearch

Benjamin Skolnik; David Wiedenfeld; Randy Dettmers; Constantino Aucca; Lina Daza; Heidy Valle; Francisco Sornoza; Javier Robayo; David Diaz; Jane Fitzgerald; Daniel Lebbin; Paul B. Hamel

2012-01-01

Vital to the work of the Cerulean Warbler Technical Group has been the collaboration among members to evaluate population status and coordinate planning for future activities, principally in conservation implementation. Two plans have been produced, one a general strategy for the conservation and management of the species over its entire range, and a more restricted...

Relating Kirtland's warbler population to changing landscape composition and structure

Treesearch

John R. Probst; Jerry Weinrich

1993-01-01

The population of male Kirtland's warbler (Dendroica kirtlandil) in the breeding season has averaged 206 from 1971 to 1987. The Kirtland's warbler occupies dense jack pine (Pinus banksiana) barrens from 5 to 23 years old and from 1.4 to 5.0 m high, formerly of wildfire origin. In 1984, 73% of the males censused were found in habitat naturally regenerated from...

Duration and rate of spring migration of Kirtland’s Warblers

Treesearch

David N. Ewert; Kimberly R. Hall; Jr. Wunderle; Dave Currie; Sarah M. Rockwell; Scott B. Johnson; Jennifer D. White

2012-01-01

The duration of migration of the endangered Kirtland’s Warbler (Setophaga kirtlandii) has not been previously documented. We estimated the average duration of spring migration for five male Kirtland’s Warblers by observing uniquely color-banded individuals at or near both the beginning and end of spring migration in Eleuthera, The Bahamas, and Michigan, respectively....

Spot-mapping underestimates song-territory size and use of mature forest by breeding golden-winged warblers in Minnesota, USA

USGS Publications Warehouse

Streby, Henry M.; Loegering, John P.; Andersen, David E.

2012-01-01

Studies of songbird breeding habitat often compare habitat characteristics of used and unused areas. Although there is usually meticulous effort to precisely and consistently measure habitat characteristics, accuracy of methods for estimating which areas are used versus which are unused by birds remains generally untested. To examine accuracy of spot-mapping to identify singing territories of golden-winged warblers (Vermivora chrysoptera), which are considered an early successional forest specialists, we used spot-mapping and radiotelemetry to record song perches and delineate song territories for breeding male golden-winged warblers in northwestern Minnesota, USA. We also used radiotelemetry to record locations (song and nonsong perches) of a subsample (n = 12) of males throughout the day to delineate home ranges. We found that telemetry-based estimates of song territories were 3 times larger and included more mature forest than those estimated from spot-mapping. In addition, home ranges estimated using radiotelemetry included more mature forest than spot-mapping- and telemetry-based song territories, with 75% of afternoon perches located in mature forest. Our results suggest that mature forest comprises a larger component of golden-winged warbler song territories and home ranges than is indicated based on spot-mapping in Minnesota. Because it appears that standard observational methods can underestimate territory size and misidentify cover-type associations for golden-winged warblers, we caution that management and conservation plans may be misinformed, and that similar studies are needed for golden-winged warblers across their range and for other songbird species.

Is Brain Emulation Dangerous?

NASA Astrophysics Data System (ADS)

Eckersley, Peter; Sandberg, Anders

2013-12-01

Brain emulation is a hypothetical but extremely transformative technology which has a non-zero chance of appearing during the next century. This paper investigates whether such a technology would also have any predictable characteristics that give it a chance of being catastrophically dangerous, and whether there are any policy levers which might be used to make it safer. We conclude that the riskiness of brain emulation probably depends on the order of the preceding research trajectory. Broadly speaking, it appears safer for brain emulation to happen sooner, because slower CPUs would make the technology`s impact more gradual. It may also be safer if brains are scanned before they are fully understood from a neuroscience perspective, thereby increasing the initial population of emulations, although this prediction is weaker and more scenario-dependent. The risks posed by brain emulation also seem strongly connected to questions about the balance of power between attackers and defenders in computer security contests. If economic property rights in CPU cycles1 are essentially enforceable, emulation appears to be comparatively safe; if CPU cycles are ultimately easy to steal, the appearance of brain emulation is more likely to be a destabilizing development for human geopolitics. Furthermore, if the computers used to run emulations can be kept secure, then it appears that making brain emulation technologies ―open‖ would make them safer. If, however, computer insecurity is deep and unavoidable, openness may actually be more dangerous. We point to some arguments that suggest the former may be true, tentatively implying that it would be good policy to work towards brain emulation using open scientific methodology and free/open source software codebases

MHC diversity in two Acrocephalus species: the outbred Great reed warbler and the inbred Seychelles warbler.

PubMed

Richardson, David S; Westerdahl, Helena

2003-12-01

The Great reed warbler (GRW) and the Seychelles warbler (SW) are congeners with markedly different demographic histories. The GRW is a normal outbred bird species while the SW population remains isolated and inbred after undergoing a severe population bottleneck. We examined variation at Major Histocompatibility Complex (MHC) class I exon 3 using restriction fragment length polymorphism, denaturing gradient gel electrophoresis and DNA sequencing. Although genetic variation was higher in the GRW, considerable variation has been maintained in the SW. The ten exon 3 sequences found in the SW were as diverged from each other as were a random sub-sample of the 67 sequences from the GRW. There was evidence for balancing selection in both species, and the phylogenetic analysis showing that the exon 3 sequences did not separate according to species, was consistent with transspecies evolution of the MHC.

Recent sightings of Kirtland's warblers on San Salvador Island, The Bahamas

Treesearch

Todd M. Jones; Michael E. Akresh; David I. King

2013-01-01

Here we present recent accounts of Kirtland's Warblers (Setophaga kirtlandii) captured and observed on San Salvador Island, The Bahamas, in 2012 and 2013. We conducted mist-netting and passive surveys in a variety of habitats on the island from January-March 2012 and December 2012-March 2013. We captured four warblers and sighted at least six...

Influence of habitat amount, arrangement, and use on population trend estimates of male Kirtland's warblers

Treesearch

Deanh M. Donner; John R. Probst; Christine A. Ribic

2008-01-01

Kirtland's warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5-23 years old) created after wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and wildfire disturbances influenced population size and spatial...

Suggestions for a Silvicultural Prescription for Cerulean Warblers in the Lower Mississippi Alluvial Valley

Treesearch

Paul B. Hamel

2005-01-01

Conservation of species with high Partners in Flight concern scores may require active habitat management. Cerulean Warbler (Dendroica cerulea) occurs at low numbers in the Lower Mississippi Alluvial Valley in the western part of its breeding range. A study of the breeding ecology of the species was initiated in 1992 on three sites there....

A comprehensive multilocus phylogeny for the wood-warblers and a revised classification of the Parulidae (Aves)

USGS Publications Warehouse

Lovette, I.J.; Perez-Eman, J. L.; Sullivan, J.P.; Banks, R.C.; Fiorentino, I.; Cordoba-Cordoba, S.; Echeverry-Galvis, M.; Barker, F.K.; Burns, K.J.; Klicka, J.; Lanyon, Scott M.; Bermingham, E.

2010-01-01

The birds in the family Parulidae-commonly termed the New World warblers or wood-warblers-are a classic model radiation for studies of ecological and behavioral differentiation. Although the monophyly of a 'core' wood-warbler clade is well established, no phylogenetic hypothesis for this group has included a full sampling of wood-warbler species diversity. We used parsimony, maximum likelihood, and Bayesian methods to reconstruct relationships among all genera and nearly all wood-warbler species, based on a matrix of mitochondrial DNA (5840 nucleotides) and nuclear DNA (6 loci, 4602 nucleotides) characters. The resulting phylogenetic hypotheses provide a highly congruent picture of wood-warbler relationships, and indicate that the traditional generic classification of these birds recognizes many non-monophyletic groups. We recommend a revised taxonomy in which each of 14 genera (Seiurus, Helmitheros, Mniotilta, Limnothlypis, Protonotaria, Parkesia, Vermivora, Oreothlypis, Geothlypis, Setophaga, Myioborus, Cardellina, Basileuterus, Myiothlypis) corresponds to a well-supported clade; these nomenclatural changes also involve subsuming a number of well-known, traditional wood-warbler genera (Catharopeza, Dendroica, Ergaticus, Euthlypis, Leucopeza, Oporornis, Parula, Phaeothlypis, Wilsonia). We provide a summary phylogenetic hypothesis that will be broadly applicable to investigations of the historical biogeography, processes of diversification, and evolution of trait variation in this well studied avian group. ?? 2010 Elsevier Inc.

How can we learn more about the Cerulean Warbler (Dendroica cerulea)

Treesearch

Paul B. Hamel; Deanna K. Dawson; Patrick D. Keyser

2004-01-01

A sense of urgency attends the study of species of concern, like the cerulean warbler (Dendroica cerulea). Sharpened by Robbins and others in 1992 and Hamel in 1992, such concern prompted the U.S. Department of the Interior, Fish and Wildlife Service (USFWS) to commission a status assessment of the cerulean warbler. Shortly after the status review was published, a...

Status of the cerulean warbler (Dendroica cerulea) in Northern Alabama, 1999-2004

Treesearch

John P. Carpenter; Eric C. Soehren; Adrian A. Lesak; Yong Wang; Callie J. Schweitzer

2005-01-01

The cerulean warbler (Dendroica cerulea) is a Neotropic-Nearctic migratory passerine that breeds in eastern North America and winters in northwestern South America (Dunn and Garrett 1997, Hamel 2000a, 2000b). The northern two-thirds of Alabama historically represented the southernmost extension of the Cerulean Warbler's breeding range, where...

Evaluation of a reproductive index for estimating songbird productivity: Case study of the golden-cheeked warbler

Treesearch

Jennifer L. Reidy; Lisa O' Donnell; Frank R. Thompson

2015-01-01

It is critically important to determine and understand relationships between endangered species populations and landscape and habitat features to effectively manage and conserve populations and the habitats they rely on. Several recent studies focused on the golden-cheeked warbler (Setophaga chrysoparia), an endangered songbird that breeds...

The effect of predation on begging-call evolution in nestling wood warblers.

PubMed

Haskell

1999-04-01

I combined a comparative study of begging in ground- and tree-nesting wood warblers (Parulidae) with experimental measures of the predation costs of warbler begging calls. Throughout their development, ground-nesting warbler nestlings had significantly higher-frequency begging calls than did tree-nesting warblers. There was also a trend for ground-nesting birds to have less rapidly modulated calls. There were no consistent associations between nesting site and the amplitude of the calls. Using miniature walkie-talkies hidden inside artificial nests, I reciprocally transplanted the begging calls of 5- and 8-day-old black-throated blue warblers, Dendroica caerulescens (tree-nesting) and ovenbirds, Seiurus aurocapillus (ground-nesting) and measured the corresponding changes in rates of nest predation. For the begging calls of 8-day-old nestlings, but not those of 5-day-olds, the calls of the tree-nesting species coming from ground nests incurred greater costs than did the calls of ground nesters. The reciprocal transplant had little effect on the rate of predation. Tooth imprints on clay eggs placed in artificial nests indicated that eastern chipmunks, Tamias striatus, were responsible for the increased cost of begging for black-throated blue calls coming from the ground. These data suggest that nest predation may be responsible for maintaining some of the interspecific differences in the acoustic structure of begging calls. Copyright 1999 The Association for the Study of Animal Behaviour.

Spatial variation in breeding habitat selection by Cerulean Warblers (Setophaga cerulea) throughout the Appalachian Mountains

USGS Publications Warehouse

Boves, Than J.; Buehler, David A.; Sheehan, James; Wood, Petra Bohall; Rodewald, Amanda D.; Larkin, Jeffrey L.; Keyser, Patrick D.; Newell, Felicity L.; Evans, Andrea; George, Gregory A.; Wigley, T.B.

2013-01-01

Studies of habitat selection are often of limited utility because they focus on small geographic areas, fail to examine behavior at multiple scales, or lack an assessment of the fitness consequences of habitat decisions. These limitations can hamper the identification of successful site-specific management strategies, which are urgently needed for severely declining species like Cerulean Warblers (Setophaga cerulea). We assessed how breeding habitat decisions made by Cerulean Warblers at multiple scales, and the subsequent effects of these decisions on nest survival, varied across the Appalachian Mountains. Selection for structural habitat features varied substantially among areas, particularly at the territory scale. Males within the least-forested landscapes selected microhabitat features that reflected more closed-canopy forest conditions, whereas males in highly forested landscapes favored features associated with canopy disturbance. Selection of nest-patch and nest-site attributes by females was more consistent across areas, with females selecting for increased tree size and understory cover and decreased basal area and midstory cover. Floristic preferences were similar across study areas: White Oak (Quercus alba), Cucumber-tree (Magnolia acuminata), and Sugar Maple (Acer saccharum) were preferred as nest trees, whereas red oak species (subgenus Erythrobalanus) and Red Maple (A. rubrum) were avoided. The habitat features that were related to nest survival also varied among study areas, and preferred features were negatively associated with nest survival at one area. Thus, our results indicate that large-scale spatial heterogeneity may influence local habitat-selection behavior and that it may be necessary to articulate site-specific management strategies for Cerulean Warblers.

Winter habitat of Kirtland's warbler: an endangered nearctic/neotropical migrant

USGS Publications Warehouse

Sykes, P.W.; Clench, M.H.

1998-01-01

Habitats of Kirtland?s Warbler (Dendroica kirtlandii) on the wintering grounds in the Bahama Archipelago are presented based upon data from 29 specimens, two bandings, and 67 sightings of at least 61 individuals on 13 islands scattered through the region. Major emphasis is placed on a study site in central Eleuthera, with additional information on sites on Grand Turk, North Caicos, and Crooked Island. The warblers used upland habitats that have a low shrub/scrub component with a patchiness of small openings and openings within the vegetation at the ground level. Six broad habitats were identified as being used: Natural Shrub/Scrub, Secondary Shrub/Scrub, Low Coppice, Pineland Understory, Saline/Upland Ecotone, and Suburban; High Coppice is not used. The structure and floristic composition of the habitats are described. Observations (N=451) of a Kirtland?s Warbler male (uniquely color banded) and female over three months indicated the birds generally stayed on or near the ground, generally < 3 m (98% of observations), and used a territory of 8.3 ha. A crude estimate of potential winter habitat suggests that there is more than an adequate amount in the Bahama Archipelago for the currently small warbler population (733 singing males in 1997) and allows for a considerable population increase. No serious future threat to the amount of that habitat is foreseen.

Cinematic camera emulation using two-dimensional color transforms

NASA Astrophysics Data System (ADS)

McElvain, Jon S.; Gish, Walter

2015-02-01

For cinematic and episodic productions, on-set look management is an important component of the creative process, and involves iterative adjustments of the set, actors, lighting and camera configuration. Instead of using the professional motion capture device to establish a particular look, the use of a smaller form factor DSLR is considered for this purpose due to its increased agility. Because the spectral response characteristics will be different between the two camera systems, a camera emulation transform is needed to approximate the behavior of the destination camera. Recently, twodimensional transforms have been shown to provide high-accuracy conversion of raw camera signals to a defined colorimetric state. In this study, the same formalism is used for camera emulation, whereby a Canon 5D Mark III DSLR is used to approximate the behavior a Red Epic cinematic camera. The spectral response characteristics for both cameras were measured and used to build 2D as well as 3x3 matrix emulation transforms. When tested on multispectral image databases, the 2D emulation transforms outperform their matrix counterparts, particularly for images containing highly chromatic content.

Simulating range-wide population and breeding habitat dynamics for an endangered woodland warbler in the face of uncertainty

USGS Publications Warehouse

Adam Duarte,; Hatfield, Jeffrey; Todd M. Swannack,; Michael R. J. Forstner,; M. Clay Green,; Floyd W. Weckerly,

2015-01-01

Population viability analyses provide a quantitative approach that seeks to predict the possible future status of a species of interest under different scenarios and, therefore, can be important components of large-scale species’ conservation programs. We created a model and simulated range-wide population and breeding habitat dynamics for an endangered woodland warbler, the golden-cheeked warbler (Setophaga chrysoparia). Habitat-transition probabilities were estimated across the warbler's breeding range by combining National Land Cover Database imagery with multistate modeling. Using these estimates, along with recently published demographic estimates, we examined if the species can remain viable into the future given the current conditions. Lastly, we evaluated if protecting a greater amount of habitat would increase the number of warblers that can be supported in the future by systematically increasing the amount of protected habitat and comparing the estimated terminal carrying capacity at the end of 50 years of simulated habitat change. The estimated habitat-transition probabilities supported the hypothesis that habitat transitions are unidirectional, whereby habitat is more likely to diminish than regenerate. The model results indicated population viability could be achieved under current conditions, depending on dispersal. However, there is considerable uncertainty associated with the population projections due to parametric uncertainty. Model results suggested that increasing the amount of protected lands would have a substantial impact on terminal carrying capacities at the end of a 50-year simulation. Notably, this study identifies the need for collecting the data required to estimate demographic parameters in relation to changes in habitat metrics and population density in multiple regions, and highlights the importance of establishing a common definition of what constitutes protected habitat, what management goals are suitable within those protected

El Grupo Cerúleo: collaboration to assess nonbreeding range of cerulean warbler in South America

USGS Publications Warehouse

Colorado, G.; Hamel, P.; Rodewald, A.; Thogmartin, W.

2008-01-01

Cerulean Warbler (Dendroica cerulea. Parulidae) has been listed as a vulnerable species by the International Union for the Conservation of Nature because of recent population declines. An international, proactive approach to Cerulean Warbler conservation, the Cerulean Warbler Technical Group, was founded in 2001. One of its subcommittees, El Grupo Cerúleo, addresses nonbreeding season issues to promote the protection of this bird through habitat conservation, field research on Cerulean Warbler winter ecology, public awareness, and the development of a predictive model to allow for assessment and monitoring of Cerulean Warbler. Most of the recent efforts of this group have been devoted to studying and understanding the spatial distribution of the Cerulean Warbler in South America through predictive models as a highly necessary strategy to elucidating the bird's occurrence, and thereby to identify and locate important nonbreeding habitats and areas of concentration in the Neotropics. To address this issue, members of EI Grupo Cerúleo developed five hypothetical models of potential distribution of the bird in the northern Andes based on existing historical records and surveys conducted by EI Grupo members. In order to validate the model output, we selected locations to verify the occurrence of the species, based on a stratified-random design, using locations where the Cerulean Warbler was predicted to occur by all five models. We elaborated field protocols to survey these locations. Resulting data will be structured for analysis using the techniques of occupancy modeling. Basic survey designs to carry out the fieldwork as well as preliminary results of the first year's fieldwork are presented. - See more at: http://www.srs.fs.usda.gov/pubs/31535#sthash.Lt3G7a8H.dpuf

WINTERING YELLOW-RUMPED WARBLERS (DENDROICA CORONATA) TRACK MANIPULATED ABUNDANCE OF MYRICA CERIFERA FRUITS

DOE Office of Scientific and Technical Information (OSTI.GOV)

K.L. Borgmann; S.F. Pearson; D.J. Levey

2004-01-01

Borgmann, K.L., S.F. Pearson, D.J. Levey, and C.H. Greenberg. 2004. Wintering yellow-rumped warblers (Dendroica coronata) track manipulated abundance of Myrica cerifera fruits. The Auk 121(1):74-87. Abstract: Food availability during winter may determine habitat use and limit populations of overwintering birds, yet its importance is difficult to judge because few studies have experimentally tested the response of nonbreeding birds to changes in resource abundance. We experimentally examined the link between fruit availability and habitat use by manipulating winter abundance of Myrica cerifera L. (Myricaceae) fruits in managed longleaf (Pinus palustris) and loblolly (P. taeda) pine stands in South Carolina. Myrica ceriferamore » is a common understory shrub in the southeastern United States and provides lipid-rich fruit in late winter (February and March), when insects and other fruits are scarce. On treatment plots, we covered fruiting M. cerifera shrubs with netting in early winter to prevent birds from eating their fruits. In late February, when M. cerifera fruit crops were largely depleted elsewhere on our study site, we uncovered the shrubs and documented the response of the bird community to those patches of high fruit availability. Relative to control plots, total bird abundance (excluding the most common species, Yellow-rumped Warbler [Dendroica coronata]) and species richness did not change after net removal. Yellow-rumped Warblers, however, became significantly more abundant on treatment plots after net removal, which suggests that they track M. cerifera fruit abundance. We suggest that M. cerifera plays a role in determining the local distribution of wintering Yellow-rumped Warblers at our study site. To put these results into a management context, we also examined the effect of prescribed fire frequencies on M. cerifera fruit production. Across pine stands with different fire regimes, M. cerifera fruit abundance increased with the number of years since

Kirtland's warbler (Setophaga kirtlandii) [revised

Treesearch

Carol I. Bocetti; Deahn M. Donner; Harold F. Mayfield

2014-01-01

The Kirtland’s Warbler (Setophaga kirtlandii), one of the rarest songbirds in North America, was first discovered when Charles Pease shot a migrant on 13 May 1851 on the farm of his father-in-law, Jared P. Kirtland, near Cleveland, OH. The new species was identified by Spencer Baird, who named it for the renowned Ohio naturalist (Baird 1852...

Application of the dynamically allocated virtual clustering management system to emulated tactical network experimentation

NASA Astrophysics Data System (ADS)

Marcus, Kelvin

2014-06-01

The U.S Army Research Laboratory (ARL) has built a "Network Science Research Lab" to support research that aims to improve their ability to analyze, predict, design, and govern complex systems that interweave the social/cognitive, information, and communication network genres. Researchers at ARL and the Network Science Collaborative Technology Alliance (NS-CTA), a collaborative research alliance funded by ARL, conducted experimentation to determine if automated network monitoring tools and task-aware agents deployed within an emulated tactical wireless network could potentially increase the retrieval of relevant data from heterogeneous distributed information nodes. ARL and NS-CTA required the capability to perform this experimentation over clusters of heterogeneous nodes with emulated wireless tactical networks where each node could contain different operating systems, application sets, and physical hardware attributes. Researchers utilized the Dynamically Allocated Virtual Clustering Management System (DAVC) to address each of the infrastructure support requirements necessary in conducting their experimentation. The DAVC is an experimentation infrastructure that provides the means to dynamically create, deploy, and manage virtual clusters of heterogeneous nodes within a cloud computing environment based upon resource utilization such as CPU load, available RAM and hard disk space. The DAVC uses 802.1Q Virtual LANs (VLANs) to prevent experimentation crosstalk and to allow for complex private networks. Clusters created by the DAVC system can be utilized for software development, experimentation, and integration with existing hardware and software. The goal of this paper is to explore how ARL and the NS-CTA leveraged the DAVC to create, deploy and manage multiple experimentation clusters to support their experimentation goals.

Male Kirtland's Warblers' patch-level response to landscape structure during periods of varying population size and habitat amounts

Treesearch

Deahn M. Donner; Christine A. Ribic; John R. Probst

2009-01-01

Forest planners must evaluate how spatiotemporal changes in habitat amount and configuration across the landscape as a result of timber management will affect species' persistence. However, there are few long-term programs available for evaluation. We investigated the response of male Kirtland's Warbler (Dendroica kirtlandii) to 26 years of...

Working on behalf of Cerulean Warblers

Treesearch

Paul B. Hamel

2009-01-01

What was mother nature thinking when she assigned ecological traits to this bird? She should have known that any species sensitive to forest fragmentation was destined to struggle. The cerulean Warbler navigates perhaps the longest migratory path of any North American Neotropical songbird. Why it should breed most effectively in Appalachian habitats where all that coal...

El Grupo Cerúleo: Cooperation for Non-breeding Season Conservation of the Cerulean Warbler

Treesearch

David Mehlman; Paul Hamel

2010-01-01

Without collaboration, conservation is impossible for long-distance migrants such as the Cerulean Warbler, a declining forest breeding bird in North America that overwinters in the Andes Mountains of South America. The Cerulean Warbler, one of the fastest declining woodland birds of eastern North America, is considered Vulnerable by BirdLife international, in the...

Kirtland’s warblers in anthropogenically disturbed early-successional habitats on Eleuthera, The Bahamas

Treesearch

Joseph Wunderle; Dave Currie; Eileen H. Helmer; David N. Ewert; Jennifer D. White; Thomas S. Ruzycki; Bernard Parresol; Charles Kwit

2010-01-01

To characterize the nonbreeding habitat of Kirtland’s Warbler (Dendroica kirtlandii) on Eleuthera, The Bahamas, we quantified the habitat at sites where we captured the warblers and compared these traits with those of random sites and sites of tall coppice. On the basis of a chronosequence of satellite imagery, 153 capture sites ranged in age from 3 to 28 years after...

Parentage assignment and extra-group paternity in a cooperative breeder: the Seychelles warbler (Acrocephalus sechellensis).

PubMed

Richardson, D S; Jury, F L; Blaakmeer, K; Komdeur, J; Burke, T

2001-09-01

We describe the development and initial application of a semiautomated parentage testing system in the Seychelles warbler (Acrocephalus sechellensis). This system used fluorescently labelled primers for 14 polymorphic microsatellite loci in two multiplex loading groups to genotype efficiently over 96% of the warbler population on Cousin island. When used in conjunction with the program CERVUS, this system provided sufficient power to assign maternity and paternity within the Seychelles warbler, despite the complications associated with its cooperative breeding system and a relatively low level of genetic variation. Parentage analyses showed that subordinate 'helper' females as well as the dominant 'primary' females laid eggs in communal nests, indicating that the Seychelles warbler has an intermediate level of female reproductive skew, in between the alternative extremes of helper-at-the-nest and joint nesting systems. Forty-four per cent of helpers bred successfully, accounting for 15% of all offspring. Forty per cent of young resulted from extra-group paternity.

Emulation for probabilistic weather forecasting

NASA Astrophysics Data System (ADS)

Cornford, Dan; Barillec, Remi

2010-05-01

Numerical weather prediction models are typically very expensive to run due to their complexity and resolution. Characterising the sensitivity of the model to its initial condition and/or to its parameters requires numerous runs of the model, which is impractical for all but the simplest models. To produce probabilistic forecasts requires knowledge of the distribution of the model outputs, given the distribution over the inputs, where the inputs include the initial conditions, boundary conditions and model parameters. Such uncertainty analysis for complex weather prediction models seems a long way off, given current computing power, with ensembles providing only a partial answer. One possible way forward that we develop in this work is the use of statistical emulators. Emulators provide an efficient statistical approximation to the model (or simulator) while quantifying the uncertainty introduced. In the emulator framework, a Gaussian process is fitted to the simulator response as a function of the simulator inputs using some training data. The emulator is essentially an interpolator of the simulator output and the response in unobserved areas is dictated by the choice of covariance structure and parameters in the Gaussian process. Suitable parameters are inferred from the data in a maximum likelihood, or Bayesian framework. Once trained, the emulator allows operations such as sensitivity analysis or uncertainty analysis to be performed at a much lower computational cost. The efficiency of emulators can be further improved by exploiting the redundancy in the simulator output through appropriate dimension reduction techniques. We demonstrate this using both Principal Component Analysis on the model output and a new reduced-rank emulator in which an optimal linear projection operator is estimated jointly with other parameters, in the context of simple low order models, such as the Lorenz 40D system. We present the application of emulators to probabilistic weather

Development of a Converter-Based Transmission Line Emulator with Three-Phase Short-Circuit Fault Emulation Capability

DOE PAGES

Zhang, Shuoting; Liu, Bo; Zheng, Sheng; ...

2018-01-01

A transmission line emulator has been developed to flexibly represent interconnected ac lines under normal operating conditions in a voltage source converter (VSC)-based power system emulation platform. As the most serious short-circuit fault condition, the three-phase short-circuit fault emulation is essential for power system studies. Here, this paper proposes a model to realize a three-phase short-circuit fault emulation at different locations along a single transmission line or one of several parallel-connected transmission lines. At the same time, a combination method is proposed to eliminate the undesired transients caused by the current reference step changes while switching between the fault statemore » and the normal state. Experiment results verify the developed transmission line three-phase short-circuit fault emulation capability.« less

Development of a Converter-Based Transmission Line Emulator with Three-Phase Short-Circuit Fault Emulation Capability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Shuoting; Liu, Bo; Zheng, Sheng

A transmission line emulator has been developed to flexibly represent interconnected ac lines under normal operating conditions in a voltage source converter (VSC)-based power system emulation platform. As the most serious short-circuit fault condition, the three-phase short-circuit fault emulation is essential for power system studies. Here, this paper proposes a model to realize a three-phase short-circuit fault emulation at different locations along a single transmission line or one of several parallel-connected transmission lines. At the same time, a combination method is proposed to eliminate the undesired transients caused by the current reference step changes while switching between the fault statemore » and the normal state. Experiment results verify the developed transmission line three-phase short-circuit fault emulation capability.« less

SWS2 visual pigment evolution as a test of historically contingent patterns of plumage color evolution in Warblers

PubMed Central

Bloch, Natasha I.; Morrow, James M.; Chang, Belinda S.W.; Price, Trevor D.

2014-01-01

Distantly related clades that occupy similar environments may differ due to the lasting imprint of their ancestors – historical contingency. The New World warblers (Parulidae) and Old World warblers (Phylloscopidae) are ecologically similar clades that differ strikingly in plumage coloration. We studied genetic and functional evolution of the short-wavelength sensitive visual pigments (SWS2 and SWS1) to ask if altered color perception could contribute to the plumage color differences between clades. We show SWS2 is short-wavelength shifted in birds that occupy open environments, such as finches, compared to those in closed environments, including warblers. Phylogenetic reconstructions indicate New World warblers were derived from a finch-like form that colonized from the Old World 15-20Ma. During this process the SWS2 gene accumulated 6 substitutions in branches leading to New World warblers, inviting the hypothesis that passage through a finch-like ancestor resulted in SWS2 evolution. In fact, we show spectral tuning remained similar across warblers as well as the finch ancestor. Results reject the hypothesis of historical contingency based on opsin spectral tuning, but point to evolution of other aspects of visual pigment function. Using the approach outlined here, historical contingency becomes a generally testable theory in systems where genotype and phenotype can be connected. PMID:25496318

Habitat-specific foraging of prothonotary warblers: Deducing habitat quality

USGS Publications Warehouse

Lyons, J.E.

2005-01-01

Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.

Using a full annual cycle model to evaluate long-term population viability of the conservation-reliant Kirtland's warbler after successful recovery

Treesearch

Donald J. Brown; Christine A. Ribic; Deahn M. Donner; Mark D. Nelson; Carol I. Bocetti; Christie M. Deloria-Sheffield; Des Thompson

2017-01-01

Long-term management planning for conservation-reliant migratory songbirds is particularly challenging because habitat quality in different stages and geographic locations of the annual cycle can have direct and carry-over effects that influence the population dynamics. The Neotropical migratory songbird Kirtland's warbler Setophaga kirtlandii...

SWS2 visual pigment evolution as a test of historically contingent patterns of plumage color evolution in warblers.

PubMed

Bloch, Natasha I; Morrow, James M; Chang, Belinda S W; Price, Trevor D

2015-02-01

Distantly related clades that occupy similar environments may differ due to the lasting imprint of their ancestors-historical contingency. The New World warblers (Parulidae) and Old World warblers (Phylloscopidae) are ecologically similar clades that differ strikingly in plumage coloration. We studied genetic and functional evolution of the short-wavelength-sensitive visual pigments (SWS2 and SWS1) to ask if altered color perception could contribute to the plumage color differences between clades. We show SWS2 is short-wavelength shifted in birds that occupy open environments, such as finches, compared to those in closed environments, including warblers. Phylogenetic reconstructions indicate New World warblers were derived from a finch-like form that colonized from the Old World 15-20 Ma. During this process, the SWS2 gene accumulated six substitutions in branches leading to New World warblers, inviting the hypothesis that passage through a finch-like ancestor resulted in SWS2 evolution. In fact, we show spectral tuning remained similar across warblers as well as the finch ancestor. Results reject the hypothesis of historical contingency based on opsin spectral tuning, but point to evolution of other aspects of visual pigment function. Using the approach outlined here, historical contingency becomes a generally testable theory in systems where genotype and phenotype can be connected. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

Space-Shuttle Emulator Software

NASA Technical Reports Server (NTRS)

Arnold, Scott; Askew, Bill; Barry, Matthew R.; Leigh, Agnes; Mermelstein, Scott; Owens, James; Payne, Dan; Pemble, Jim; Sollinger, John; Thompson, Hiram;

Passing the baton of action from research to conservation implementation for Cerulean Warbler (Setophaga cerulea)

Treesearch

Paul. B. Hamel; David Mehlman; Sebastian Herzog; Kenneth C. Rosenberg; Jason Jones

2012-01-01

When El Grupo Cerúleo, a sub-committee of the Cerulean Warbler Technical Group, was formed in 2002, the task of elucidating the nonbreeding distribution, ecology and behavior of the Cerulean Warbler (Setophaga cerulea) was large, our understanding of habitat needs was limited, there was fear that little suitable habitat existed, and conservation partnerships within...

Interspecific song imitation by a Prairie Warbler

Treesearch

Bruce E. Byers; Brodie A. Kramer; Michael E. Akresh; David I. King

2013-01-01

Song development in oscine songbirds relies on imitation of adult singers and thus leaves developing birds vulnerable to potentially costly errors caused by imitation of inappropriate models, such as the songs of other species. In May and June 2012, we recorded the songs of a bird that made such an error: a male Prairie Warbler (Setophaga discolor)...

Landscape and local effects on occupancy and densities of an endangered wood-warbler in an urbanizing landscape

Treesearch

Jennifer L. Reidy; Frank R. Thompson; Courtney Amundson; Lisa O' Donnell

2016-01-01

Context. Golden-cheeked warblers (Setophaga chrysoparia), an endangered wood-warbler, breed exclusively in woodlands co-dominated by Ashe juniper (Juniperus ashei) in central Texas. Their breeding range is becoming increasingly urbanized and habitat loss and fragmentation are a main threat to the species' viability....

Reed Warbler Hosts Fine-Tune their Defenses to Track Three Decades of Cuckoo Decline

PubMed Central

Thorogood, Rose; Davies, Nicholas B

2013-01-01

Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat parasitism by common cuckoos (Cuculus canorus). During the past three decades cuckoos have declined markedly across England, reducing parasitism at our study site (Wicken Fen) from 24% of reed warbler nests in 1985 to 1% in 2012. Here we show with experiments that host mobbing and egg rejection defenses have tracked this decline in local parasitism risk: the proportion of reed warbler pairs mobbing adult cuckoos (assessed by responses to cuckoo mounts and models) has declined from 90% to 38%, and the proportion rejecting nonmimetic cuckoo eggs (assessed by responses to model eggs) has declined from 61% to 11%. This is despite no change in response to other nest enemies or mimetic model eggs. Individual variation in both defenses is predicted by parasitism risk during the host’s egg-laying period. Furthermore, the response of our study population to temporal variation in parasitism risk can also explain spatial variation in egg rejection behavior in other populations across Europe. We suggest that spatial and temporal variation in parasitism risk has led to the evolution of plasticity in reed warbler defenses. PMID:24299407

Natal dispersal patterns are not associated with inbreeding avoidance in the Seychelles warbler.

PubMed

Eikenaar, C; Komdeur, J; Richardson, D S

2008-07-01

In this study, we test whether patterns of territory inheritance, social mate choice and female-biased natal dispersal act as inbreeding avoidance mechanisms in the cooperatively breeding Seychelles warbler. Our results show that Seychelles warblers do not reduce the likelihood of inbreeding by avoiding related individuals as mates. The occurrence of natural and experimentally induced territory inheritance did not depend on whether the remaining breeder was a parent of the potential inheritor or an unrelated breeder. Furthermore, dispersing individuals were no less related to their eventual mates than expected given the pool of candidates they could mate with. The female bias in natal dispersal distance observed in the Seychelles warbler does not facilitate inbreeding avoidance because, contrary to our prediction, there was no sex difference in the clustering of related opposite sex breeders around the natal territories of dispersers. As a result, the chance of females mating with relatives was not reduced by their greater dispersal distance compared with that of males.

Singing behavior of the Swainson's warbler

USGS Publications Warehouse

Meanley, B.

1968-01-01

Studies of the singing behavior of the Swainson?s Warbler were conducted mainly near Macon, Bibb County, Georgia, and in the Dismal Swamp, Nansemond County, Virginia, during the springs of 1965 and 1966. Singing behavior on the ground and in trees is discussed. Swainson?s Warblers sing vigorously from the time they arrive on the breeding ground until the latter part of June, when the singing of most birds becomes more sporadic. At Macon, Georgia, in mid-April, morning song of one bird began about 20 minutes before sunrise; and evening song of the same bird ceased about 15 minutes after sunset. Songs were delivered at the rate of about 8-9 per minute for the first few minutes of morning song, decreasing to 5-6 per minute for most of the morning. Songs are given in courses or series. The rate of singing is usually faster at the beginning of a course. The number of songs sung by a territorial male in 1 day in the Dismal Swamp, Virginia, 2 June, was 1168. It produced 280 songs the first hour, and sang at a fairly constant rate from 5:00 to 8:00 AM, 192, 194, 198 songs per hour.

Case study: Prioritization strategies for reforestation of minelands to benefit Cerulean Warblers

USGS Publications Warehouse

McDermott, Molly E.; Shumar, Matthew B.; Wood, Petra Bohall

2013-01-01

The central Appalachian landscape is being heavily altered by surface coal mining. The practice of Mountaintop Removal/Valley Fill (MTRVF) mining has transformed large areas of mature forest to non-forest and created much forest edge, affecting habitat quality for mature forest wildlife. The Appalachian Regional Reforestation Initiative is working to restore mined areas to native hardwood forest conditions, and strategies are needed to prioritize restoration efforts for wildlife. We present mineland reforestation guidelines for the imperiled Cerulean Warbler, considered a useful umbrella species, in its breeding range. In 2009, we surveyed forest predicted to have Cerulean Warblers near mined areas in the MTRVF region of West Virginia and Kentucky. We visited 36 transect routes and completed songbird surveys on 151 points along these routes. Cerulean Warblers were present at points with fewer large-scale canopy disturbances and more mature oak-hickory forest. We tested the accuracy of a predictive map for this species and demonstrated that it can be useful to guide reforestation efforts. We then developed a map of hot spot locations that can be used to determine potential habitat suitability. Restoration efforts would have greatest benefit for Cerulean Warblers and other mature forest birds if concentrated near a relative-abundance hot spot, on north- and east-facing ridgetops surrounded by mature deciduous forest, and prioritized to reduce edges and connect isolated forest patches. Our multi-scale approach for prioritizing restoration efforts using an umbrella species may be applied to restore habitat impacted by a variety of landscape disturbances.

Diagnostic emulation: Implementation and user's guide

NASA Technical Reports Server (NTRS)

Becher, Bernice

1987-01-01

The Diagnostic Emulation Technique was developed within the System Validation Methods Branch as a part of the development of methods for the analysis of the reliability of highly reliable, fault tolerant digital avionics systems. This is a general technique which allows for the emulation of a digital hardware system. The technique is general in the sense that it is completely independent of the particular target hardware which is being emulated. Parts of the system are described and emulated at the logic or gate level, while other parts of the system are described and emulated at the functional level. This algorithm allows for the insertion of faults into the system, and for the observation of the response of the system to these faults. This allows for controlled and accelerated testing of system reaction to hardware failures in the target machine. This document describes in detail how the algorithm was implemented at NASA Langley Research Center and gives instructions for using the system.

Hooded Warbler Nesting Success Adjacent to Group-selection and Clearcut Edges in a Southeastern Bottomland Forest

Treesearch

Christopher E. Moorman; David C. Guynn; John C. Kilgo

2002-01-01

During the 1996, 1997, and 199X breeding seasons, WC located and monitored Hooded Warbler (Wilsonia citrina) nests in a bottomland forest and examined the effects of edge proximity, edge type, and nest-site vegetation on nesting success. SW- cessful Hooded Warbler nests were more concealed from below and were located in nest patches with a greater...

A partly albino Wilson's Warbler (Wilsonia pusilla)

Treesearch

Wang Yong; Deborah M. Finch

1997-01-01

On 20 September 1995 at 11:15 MST, during routine mist-netting for a study investigating the use of the middle Rio Grande riparian habitat by migratory land birds at Rio Grande Nature Center, Bernalillo County, New Mexico, we were surprised to discover a light yellowish warbler in one of the nets. After careful examination and comparison, the bird was identified as a...

Geolocators on Golden-winged Warblers do not affect migratory ecology

USGS Publications Warehouse

Peterson, Sean M.; Streby, Henry M.; Kramer, Gunnar R.; Lehman, Justin A.; Buehler, David A.; Andersen, David E.

2015-01-01

The use of light-level geolocators is increasingly common for connecting breeding and nonbreeding sites and identifying migration routes in birds. Until recently, the mass and size of geolocators precluded their use on songbird species weighing <12 g. Reducing the mass of geolocators, such as by shortening or eliminating the light stalk, may make their deployment on small birds feasible, but may also inhibit their ability to receive light reliably, because small geolocators can be shaded by feathers. Here we report geolocator effects on migratory ecology of Golden-winged Warblers (Vermivora chrysoptera) in Minnesota and Tennessee. We also evaluated whether stalk length influenced precision of location data for birds on the breeding grounds. At 8–10 g, Golden-winged Warblers are the smallest birds to be outfitted with geolocators to date. We found no differences in return rates, inter-annual territory fidelity, or body mass between geolocator-marked individuals and a control group of color-banded individuals. We observed no difference in return rates or variation in estimated breeding locations between birds marked with stalked geolocators and those with stalkless geolocators. Our results suggest that some small songbirds can be safely marked with geolocators. Light stalks appear to be unnecessary for Golden-winged Warblers; the added mass and drag of stalks can probably be eliminated on other small songbirds.

Population and habitat viability assessments for Golden-cheeked Warblers and Black-capped Vireos: Usefulness to Partners in Flight Conservation Planning

USGS Publications Warehouse

Beardmore, C.J.; Hatfield, J.S.; Bonney, Rick; Pashley, David N.; Cooper, Robert; Niles, Larry

2000-01-01

Golden-cheeked Warblers and Black-capped Vireos are Neotropical migratory birds that are federally listed as endangered. Recovery plans for both species advise the use of viability modeling as a tool for setting specific recovery and management targets. Population and Habitat Viability Assessment workshops were conducted to develop population targets and conservation recommendations for these species. Results of the workshops were based on modeling demographic and environmental factors, as well as discussions of management issues, management options, and public outreach strategies. The approach is intended to be iterative, and to be tracked by research and monitoring efforts. This paper discusses the consensus-building workshop process and how the approach could be useful to Partners in Flight. Population and Habitat Viability Assessments (PHVA) were used to develop population targets and conservation recommendations for Golden-cheeked Warblers (Dendroica chrysoparia) and Black-capped Vireos (Vireo atricapillus). This paper explains what PHVAs are, discusses how they are conducted, describes the general results that are produced, and suggests how Partners in Flight (PIF) might use a similar process for bird conservation planning. Detailed results of the assessments are not discussed here; however they can be found elsewhere (U. S. Fish and Wildlife Service 1996a, U. S. Fish and Wildlife Service 1996b). PHVAs were considered for Golden-cheeked Warblers and Black-capped Vireos because they are controversial, endangered species, and the species? recovery plans list PHVAs as tools to develop recovery recommendations. The U. S. Fish and Wildlife Service (USFWS) realized that the data needed to perform PHVAs for these species is limited, but that various conservation efforts, such as the Balcones Canyonlands Conservation Plan and other endeavors, were proceeding without benefit of the biological summarization and guidance that a PHVA could provide.

Emulator-assisted data assimilation in complex models

NASA Astrophysics Data System (ADS)

Margvelashvili, Nugzar Yu; Herzfeld, Mike; Rizwi, Farhan; Mongin, Mathieu; Baird, Mark E.; Jones, Emlyn; Schaffelke, Britta; King, Edward; Schroeder, Thomas

2016-09-01

Emulators are surrogates of complex models that run orders of magnitude faster than the original model. The utility of emulators for the data assimilation into ocean models is still not well understood. High complexity of ocean models translates into high uncertainty of the corresponding emulators which may undermine the quality of the assimilation schemes based on such emulators. Numerical experiments with a chaotic Lorenz-95 model are conducted to illustrate this point and suggest a strategy to alleviate this problem through the localization of the emulation and data assimilation procedures. Insights gained through these experiments are used to design and implement data assimilation scenario for a 3D fine-resolution sediment transport model of the Great Barrier Reef (GBR), Australia.

Dynamic Emulation Modelling (DEMo) of large physically-based environmental models

NASA Astrophysics Data System (ADS)

Galelli, S.; Castelletti, A.

2012-12-01

In environmental modelling large, spatially-distributed, physically-based models are widely adopted to describe the dynamics of physical, social and economic processes. Such an accurate process characterization comes, however, to a price: the computational requirements of these models are considerably high and prevent their use in any problem requiring hundreds or thousands of model runs to be satisfactory solved. Typical examples include optimal planning and management, data assimilation, inverse modelling and sensitivity analysis. An effective approach to overcome this limitation is to perform a top-down reduction of the physically-based model by identifying a simplified, computationally efficient emulator, constructed from and then used in place of the original model in highly resource-demanding tasks. The underlying idea is that not all the process details in the original model are equally important and relevant to the dynamics of the outputs of interest for the type of problem considered. Emulation modelling has been successfully applied in many environmental applications, however most of the literature considers non-dynamic emulators (e.g. metamodels, response surfaces and surrogate models), where the original dynamical model is reduced to a static map between input and the output of interest. In this study we focus on Dynamic Emulation Modelling (DEMo), a methodological approach that preserves the dynamic nature of the original physically-based model, with consequent advantages in a wide variety of problem areas. In particular, we propose a new data-driven DEMo approach that combines the many advantages of data-driven modelling in representing complex, non-linear relationships, but preserves the state-space representation typical of process-based models, which is both particularly effective in some applications (e.g. optimal management and data assimilation) and facilitates the ex-post physical interpretation of the emulator structure, thus enhancing the

Museum DNA reveals the demographic history of the endangered Seychelles warbler.

PubMed

Spurgin, Lewis G; Wright, David J; van der Velde, Marco; Collar, Nigel J; Komdeur, Jan; Burke, Terry; Richardson, David S

2014-11-01

The importance of evolutionary conservation - how understanding evolutionary forces can help guide conservation decisions - is widely recognized. However, the historical demography of many endangered species is unknown, despite the fact that this can have important implications for contemporary ecological processes and for extinction risk. Here, we reconstruct the population history of the Seychelles warbler (Acrocephalus sechellensis) - an ecological model species. By the 1960s, this species was on the brink of extinction, but its previous history is unknown. We used DNA samples from contemporary and museum specimens spanning 140 years to reconstruct bottleneck history. We found a 25% reduction in genetic diversity between museum and contemporary populations, and strong genetic structure. Simulations indicate that the Seychelles warbler was bottlenecked from a large population, with an ancestral N e of several thousands falling to <50 within the last century. Such a rapid decline, due to anthropogenic factors, has important implications for extinction risk in the Seychelles warbler, and our results will inform conservation practices. Reconstructing the population history of this species also allows us to better understand patterns of genetic diversity, inbreeding and promiscuity in the contemporary populations. Our approaches can be applied across species to test ecological hypotheses and inform conservation.

Museum DNA reveals the demographic history of the endangered Seychelles warbler

PubMed Central

Spurgin, Lewis G; Wright, David J; van der Velde, Marco; Collar, Nigel J; Komdeur, Jan; Burke, Terry; Richardson, David S

2014-01-01

The importance of evolutionary conservation – how understanding evolutionary forces can help guide conservation decisions – is widely recognized. However, the historical demography of many endangered species is unknown, despite the fact that this can have important implications for contemporary ecological processes and for extinction risk. Here, we reconstruct the population history of the Seychelles warbler (Acrocephalus sechellensis) – an ecological model species. By the 1960s, this species was on the brink of extinction, but its previous history is unknown. We used DNA samples from contemporary and museum specimens spanning 140 years to reconstruct bottleneck history. We found a 25% reduction in genetic diversity between museum and contemporary populations, and strong genetic structure. Simulations indicate that the Seychelles warbler was bottlenecked from a large population, with an ancestral Ne of several thousands falling to <50 within the last century. Such a rapid decline, due to anthropogenic factors, has important implications for extinction risk in the Seychelles warbler, and our results will inform conservation practices. Reconstructing the population history of this species also allows us to better understand patterns of genetic diversity, inbreeding and promiscuity in the contemporary populations. Our approaches can be applied across species to test ecological hypotheses and inform conservation. PMID:25553073

Reed warbler hosts fine-tune their defenses to track three decades of cuckoo decline.

PubMed

Thorogood, Rose; Davies, Nicholas B

2013-12-01

Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat parasitism by common cuckoos (Cuculus canorus). During the past three decades cuckoos have declined markedly across England, reducing parasitism at our study site (Wicken Fen) from 24% of reed warbler nests in 1985 to 1% in 2012. Here we show with experiments that host mobbing and egg rejection defenses have tracked this decline in local parasitism risk: the proportion of reed warbler pairs mobbing adult cuckoos (assessed by responses to cuckoo mounts and models) has declined from 90% to 38%, and the proportion rejecting nonmimetic cuckoo eggs (assessed by responses to model eggs) has declined from 61% to 11%. This is despite no change in response to other nest enemies or mimetic model eggs. Individual variation in both defenses is predicted by parasitism risk during the host's egg-laying period. Furthermore, the response of our study population to temporal variation in parasitism risk can also explain spatial variation in egg rejection behavior in other populations across Europe. We suggest that spatial and temporal variation in parasitism risk has led to the evolution of plasticity in reed warbler defenses. © 2013 The Authors. Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Personal-Computer Video-Terminal Emulator

NASA Technical Reports Server (NTRS)

Buckley, R. H.; Koromilas, A.; Smith, R. M.; Lee, G. E.; Giering, E. W.

1985-01-01

OWL-1200 video terminal emulator has been written for IBM Personal Computer. The OWL-1200 is a simple user terminal with some intelligent capabilities. These capabilities include screen formatting and block transmission of data. Emulator is written in PASCAL and Assembler for the IBM Personal Computer operating under DOS 1.1.

Male Kirtland's Warblers' patch-level response to landscape structure during periods of varying population size and habitat amounts

USGS Publications Warehouse

Donner, D.M.; Ribic, C.A.; Probst, J.R.

2009-01-01

Forest planners must evaluate how spatiotemporal changes in habitat amount and configuration across the landscape as a result of timber management will affect species' persistence. However, there are few long-term programs available for evaluation. We investigated the response of male Kirtland's Warbler (Dendroica kirtlandii) to 26 years of changing patch and landscape structure during a large, 26-year forestry-habitat restoration program within the warbler's primary breeding range. We found that the average density of male Kirtland's Warblers was related to a different combination of patch and landscape attributes depending on the species' regional population level and habitat amounts on the landscape (early succession jack pine (Pinus banksiana) forests; 15-42% habitat cover). Specifically, patch age and habitat regeneration type were important at low male population and total habitat amounts, while patch age and distance to an occupied patch were important at relatively high population and habitat amounts. Patch age and size were more important at increasing population levels and an intermediate amount of habitat. The importance of patch age to average male density during all periods reflects the temporal buildup and decline of male numbers as habitat suitability within the patch changed with succession. Habitat selection (i.e., preference for wildfire-regenerated habitat) and availability may explain the importance of habitat type and patch size during lower population and habitat levels. The relationship between male density and distance when there was the most habitat on the landscape and the male population was large and still increasing may be explained by the widening spatial dispersion of the increasing male population at the regional scale. Because creating or preserving habitat is not a random process, management efforts would benefit from more investigations of managed population responses to changes in spatial structure that occur through habitat gain

Effects of habitat change along Breeding Bird Survey routes in the central Appalachians on Cerulean Warbler population

USGS Publications Warehouse

McElhone, P.; Wood, P.W.; Dawson, D.

2007-01-01

The cerulean warbler (Dendroica cerulea) is one of the highest priority bird species in the eastern United States because populations have declined 4.3% annually during 1966?2005 based on Breeding Bird Survey (BBS) data. Habitat loss and fragmentation due to land use changes is thought to be one of the major factors contributing to the decline. BBS routes, the primary source for monitoring bird population trends, include 50 sampling stops every 0.8 km. Although data from BBS routes are extrapolated to determine regional trends in bird populations, it is important to understand the effects of habitat changes at the stop-level along BBS routes. Route-level analysis of habitat changes may mask important changes that are occurring at a smaller scale particularly for the cerulean warbler which displays several micro-scale habitat preferences. We are examining cerulean warbler habitat and population changes in its core breeding range of the Ohio Hills and Cumberland Plateau physiographic regions. We quantified land cover changes within 300 m of BBS routes in the core cerulean warbler breeding range of Ohio, West Virginia, and Kentucky by digitizing aerial photographs from two time periods: the 1980s and 2004. We also quantified land cover changes within 300 m of BBS routes with the National Land Cover Dataset (NLCD) from 1992 and 2001. The hand-digitized aerial photos will be compared with the NLCD to determine how similar the two methods are in quantifying land cover changes. We then compared stop-level land cover changes with stop level changes in cerulean warbler detections within the same time periods along the BBS routes. This will allow for a more detailed analysis of how well habitat changes along BBS routes reflect the changes in cerulean warbler populations.

Comparing census methods for the endangered Kirtland's Warbler

Treesearch

John R. Probst; Deahn M. Donner; Mike Worland; Jerry Weinrich; Phillip Huber; Kenneth R. Ennis

2005-01-01

We compared transect counts used for the annual official count of male Kirtland`s Warblers (Dendroica kirtlandii) to an observation-based mapping method of individually sighted males in 155 stands over 10 yrs. The annual census count almost tripled from 1990 to 1999. The transect and observation-based mapping method showed the same increasing trend...

Emulation as an Integrating Principle for Cognition

PubMed Central

Colder, Brian

2011-01-01

Emulations, defined as ongoing internal representations of potential actions and the futures those actions are expected to produce, play a critical role in directing human bodily activities. Studies of gross motor behavior, perception, allocation of attention, response to errors, interoception, and homeostatic activities, and higher cognitive reasoning suggest that the proper execution of all these functions relies on emulations. Further evidence supports the notion that reinforcement learning in humans is aimed at updating emulations, and that action selection occurs via the advancement of preferred emulations toward realization of their action and environmental prediction. Emulations are hypothesized to exist as distributed active networks of neurons in cortical and sub-cortical structures. This manuscript ties together previously unrelated theories of the role of prediction in different aspects of human information processing to create an integrated framework for cognition. PMID:21660288

Processor Emulator with Benchmark Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lloyd, G. Scott; Pearce, Roger; Gokhale, Maya

2015-11-13

A processor emulator and a suite of benchmark applications have been developed to assist in characterizing the performance of data-centric workloads on current and future computer architectures. Some of the applications have been collected from other open source projects. For more details on the emulator and an example of its usage, see reference [1].

Evaluating outcomes of management targeting the recovery of a migratory songbird of conservation concern.

PubMed

Streby, Henry M; Kramer, Gunnar R; Peterson, Sean M; Andersen, David E

2018-01-01

Assessing outcomes of habitat management is critical for informing and adapting conservation plans. From 2013-2019, a multi-stage management initiative, led by the American Bird Conservancy (ABC), aims to create >25,000 ha of shrubland and early-successional vegetation to benefit Golden-winged Warblers ( Vermivora chrysoptera ) in managed forested landscapes of the western Great Lakes region. We studied a dense breeding population of Golden-winged Warblers at Rice Lake National Wildlife Refuge (NWR) in Minnesota, USA, where ABC initiative management was implemented to benefit the species. We monitored abundance before (2011-2014) and after (2015-2016) management, and we estimated full-season productivity (i.e., young recruited into the fall population) from predictive, spatially explicit models, informed by nest and fledgling survival data collected at sites in the western Great Lakes region, including Rice Lake NWR, during 2011 and 2012. Then, using biologically informed models of bird response to observed and predicted vegetation succession, we estimated the cumulative change in population recruitment over various scenarios of vegetation succession and demographic response. We observed an 32% decline in abundance of breeding pairs and estimated a 27% decline in per-pair full-season productivity following management, compared to no change in a nearby control site. In models that ranged from highly optimistic to progressively more realistic scenarios, we estimated a net loss of 72-460 juvenile Golden-winged Warblers produced from the managed site in the 10-20 years following management. Even if our well-informed and locally validated productivity models produced erroneous estimates and the management resulted in only a temporary reduction in abundance (i.e., no change in productivity), our forecast models still predicted a net loss of 137-260 juvenile Golden-winged Warblers from the managed area over the same time frame. Our study site represents only a small

Nonbreeding golden-winged warbler, habitat: status, conservation, and needs

Treesearch

David I. King; Richard B. Chandler; Curtis Smalling; Richard Trubey; Raul Raudales; Tom Will

2016-01-01

Anecdotal reports and more recent quantitative findings suggest Golden-winged Warblers (Vermivora chrysoptera) are most abundant in midelevation moist forests of Central America during the nonbreeding season. The species appears to be tolerant of moderate levels of disturbance, inhabiting both primary and secondary forest; however, occupation of...

Luring in Cerulean Warblers, honoring the volunteer spirit

Treesearch

Paul Hamel

2008-01-01

What is it about the cerulean warbler - sometimes described as a "piece of sky" - that inspires people to trek out into the hot, buggy Arkansas woods in the middle of June? The story we'll tell here - partly in his own rather succinct words - is that of a Doc Weaver, a retired general practitioner who has given his...

Guidance, Navigation and Control Digital Emulation Technology Laboratory. Volume 1. Part 2. Task 1: Digital Emulation Technology Laboratory

DTIC Science & Technology

1991-09-27

AD-A241 692 II I] II I11 ANNUAL REPORT VOLUME 1 PART 2 TASK 1: DIGITAL EMULATION TECHNOLOGY LABORATOIRY REPORT NO. AR-0142-91-001 September 27, 1991... DIGITAL EMULATION TECHNOLOGY LABORATORY Contract No. DASG60-89-C-0142 Sponsored By The United States Army ? trategic Defense Command COMPUTER...ANNUAL REPORT VOLUME 1 PART 2 TASK 1: DIGITAL EMULATION TECHNOLOGY LABORATORY September 27, 1991 Authors Thomas R. Collins and Stephen R. Wachtel

Stopover ecology and habitat use of migratory Wilson's Warblers

Treesearch

Wang Yong; Deborah M. Finch; Frank R. Moore; Jeffrey F. Kelly

1998-01-01

The conservation of long-distance migratory songbirds is complicated by their life-history characteristics and the spatial scales that they traverse. Events during migratory stopovers may have significant consequences in determining the population status of migratory songbirds. Using Wilson's Warbler (Wilsonia pusilla) as a focal species, we investigated effects...

Elevational gradient in clutch size of Red-faced Warblers

USGS Publications Warehouse

Dillon, Kristen G.; Conway, Courtney J.

2015-01-01

Our understanding of life history evolution has benefited from debates regarding the underlying causes, and geographic ubiquity, of spatial patterns in avian clutch sizes. Past studies have revealed that birds lay smaller clutch sizes at higher elevation. However, in most previous studies, investigators have failed to adequately control for elevational differences in breeding phenology. To better understand the elevational gradient in avian clutch size, we need to know how clutch size changes across the entire elevational breeding range of a species (i.e., the shape of the relationship between elevation and clutch size), and whether the elevational gradient in clutch size is merely an artifact of elevational gradients in breeding phenology or breeding season length. We examined the relationship between breeding elevation and clutch size of Red-faced Warblers (Cardellina rubrifrons) along a 1000-m elevational gradient in Arizona. Our objectives were to determine how clutch size changed with elevation, and if the relationship between clutch size and elevation merely reflected elevational changes in breeding season length or phenology. The proportion of 5-egg clutches decreased and the proportion of 3- and 4-egg clutches increased non-linearly with increasing elevation, even after controlling for the elevational gradient in nest initiation date. Thus, average clutch size declined across the elevational breeding range of Red-faced Warblers, but this decline was not due to elevational variation in breeding phenology. Timing of breeding changed, but the duration of the breeding season did not change appreciably across the elevational gradient. Hence, elevational differences in breeding season length or breeding phenology cannot explain why Red-faced Warblers (and perhaps other birds) breeding at higher elevations have smaller clutches.

Population trends in Vermivora warblers are linked to strong migratory connectivity

USGS Publications Warehouse

Kramer, Gunnar R.; Andersen, David; Buehler, David A.; Wood, Petra B.; Peterson, Sean M.; Lehman, Justin A.; Aldinger, Kyle R.; Bulluck, Lesley P.; Harding, Sergio R.; Jones, John A.; Loegering, John P.; Smalling, Curtis G.; Vallender, Rachel; Streby, Henry M.

2018-01-01

Migratory species can experience limiting factors at different locations and during different periods of their annual cycle. In migratory birds, these factors may even occur in different hemispheres. Therefore, identifying the distribution of populations throughout their annual cycle (i.e., migratory connectivity) can reveal the complex ecological and evolutionary relationships that link species and ecosystems across the globe and illuminate where and how limiting factors influence population trends. A growing body of literature continues to identify species that exhibit weak connectivity wherein individuals from distinct breeding areas co-occur during the nonbreeding period. A detailed account of a broadly distributed species exhibiting strong migratory connectivity in which nonbreeding isolation of populations is associated with differential population trends remains undescribed. Here, we present a range-wide assessment of the nonbreeding distribution and migratory connectivity of two broadly dispersed Nearctic-Neotropical migratory songbirds. We used geolocators to track the movements of 70 Vermivora warblers from sites spanning their breeding distribution in eastern North America and identified links between breeding populations and nonbreeding areas. Unlike blue-winged warblers (Vermivora cyanoptera), breeding populations of golden-winged warblers (Vermivora chrysoptera) exhibited strong migratory connectivity, which was associated with historical trends in breeding populations: stable for populations that winter in Central America and declining for those that winter in northern South America.

Pre-nesting and nesting behavior of the Swainson's warbler

USGS Publications Warehouse

Meanley, B.

1969-01-01

The Swainson?s Warbler is one of the least known of southern birds. Although fairly common in some parts of its summer range, observations of its breeding biology have been made by very few persons. The present study was conducted mostly at Macon, Georgia; Pendleton Ferry, Arkansas; and Dismal Swamp, Virginia....In central Georgia and east-central Arkansas, Swainson?s Warblers usually arrive on their territories during the first two weeks in April. Territories in several localities ranged in size from 0.3 to 4.8 acres. A color-marked Arkansas male occupied the same territory for at least four months. Hostile encounters between territorial male Swainson?s Warblers usually take place along the boundary of adjacent territories. Paired males were more aggressive than unpaired males. Toward the end of an encounter one of the two males would usually perform a display in which the wing and tail feathers were spread and the tail vibrated. Following boundary encounters males drifted back onto their territories and usually sang unbroken courses of songs for several minutes.....During pre-nesting at Macon, a mated pair spent the day mostly on the ground within 20 feet of each other, often foragin g 3 to 4 feet apart. What may have been a form of courtship display, in which the male flew from a perch down to the female and either pecked her rump or pounced on her, occurred about three times each hour throughout the day. During this period the male sang less than at other times during the breeding season.....First nests are usually built by the first week in May. Although other investigators reported finding nests of this species outside of the defended territory, all nests that I have found were within the territory. The large, bulky nest of this species usually is placed 2-6 feet above the ground. It is built by the female from materials gathered close to the nest site; and takes two or three days to complete.....Three and occasionally four white eggs are laid. The female

Modeling the South American range of the cerulean warbler

Treesearch

S. Barker; S. Benítez; J. Baldy; D. Cisneros Heredia; G. Colorado Zuluaga; F. Cuesta; I. Davidson; D. Díaz; A. Ganzenmueller; S. García; M. K. Girvan; E. Guevara; P. Hamel; A. B. Hennessey; O. L. Hernández; S. Herzog; D. Mehlman; M. I. Moreno; E. Ozdenerol; P. Ramoni-Perazzi; M. Romero; D. Romo; P. Salaman; T. Santander; C. Tovar; M. Welton; T. Will; C. Galindo Pedraza

2007-01-01

Successful conservation of rare species requires detailed knowledge of the species’ distribution. Modeling spatial distribution is an efficient means of locating potential habitats. Cerulean Warbler (Dendroica cerulea, Parulidae) was listed as a Vulnerable Species by the International Union for the Conservation of Nature and Natural Resources in 2004...

Modeling the South American range of the cerulean warbler

Treesearch

S. Barker; S. Benítez; J. Baldy; D. Cisneros Heredia; G. Colorado Zuluaga; F. Cuesta; I. Davidson; D. Díaz; A. Ganzenmueller; S. García; M. K. Girvan; E. Guevara; P. Hamel; A. B. Hennessey; O. L. Hernández; S. Herzog; D. Mehlman; M. I. Moreno; E. Ozdenerol; P. Ramoni-Perazzi; M. Romero; D. Romo; P. Salaman; T. Santander; C. Tovar; M. Welton; T. Will; C. Pedraza; G. Galindo

2006-01-01

Successful conservation of rare species requires detailed knowledge of the species’ distribution. Modeling spatial distribution is an efficient means of locating potential habitats. Cerulean Warbler (Dendroica cerulea, Parulidae) was listed as a Vulnerable Species by the International Union for the Conservation of Nature and Natural Resources in...

Becoming-Speckled Warbler: Re/Creating Australian Natural History Pedagogy

ERIC Educational Resources Information Center

Stewart, Alistair

2011-01-01

The speckled warbler and other woodland birds of south-eastern Australia have declined dramatically since European settlement; many species are at risk of becoming locally and/or nationally extinct. Coincidently, Australian environmental education research of the last decade has largely been silent on the development of pedagogy that reflects the…

Senescence in the wild: Insights from a long-term study on Seychelles warblers.

PubMed

Hammers, Martijn; Kingma, Sjouke A; Bebbington, Kat; van de Crommenacker, Janske; Spurgin, Lewis G; Richardson, David S; Burke, Terry; Dugdale, Hannah L; Komdeur, Jan

2015-11-01

Senescence--the progressive age-dependent decline in performance--occurs in most organisms. There is considerable variation in the onset and rate of senescence between and within species. Yet the causes of this variation are still poorly understood, despite being central to understanding the evolution of senescence. Long-term longitudinal studies on wild animals are extremely well-suited to studying the impact of environmental and individual characteristics (and the interaction between the two) on senescence, and can help us to understand the mechanisms that shape the evolution of senescence. In this review, we summarize and discuss the insights gained from our comprehensive long-term individual-based study of the Seychelles warbler (Acrocephalus sechellensis). This species provides an excellent model system in which to investigate the evolution of senescence in the wild. We found that Seychelles warblers show senescent declines in survival and reproduction, and discuss how individual characteristics (body condition, body size) and environmental effects (low- versus high-quality environments) may affect the onset and rate of senescence. Further, we highlight the evidence for trade-offs between early-life investment and senescence. We describe how key cellular and physiological processes (oxidative stress and telomere shortening) underpinning senescence are affected by individual and environmental characteristics in the Seychelles warbler (e.g. food availability, reproductive investment, disease) and we discuss how such physiological variation may mediate the relationship between environmental characteristics and senescence. Based on our work using Seychelles warblers as a model system, we show how insights from long-term studies of wild animals may help unravel the causes of the remarkable variation in senescence observed in natural systems, and highlight areas for promising future research.

Reproductive success and habitat characteristics of Golden-winged Warblers in high-elevation pasturelands

USGS Publications Warehouse

Wood, Petra; Aldinger, Kyle R.

2016-01-01

The Golden-winged Warbler (Vermivora chrysoptera) is one of the most rapidly declining vertebrate species in the Appalachian Mountains. It is the subject of extensive range-wide research and conservation action. However, little is known about this species' breeding ecology in high-elevation pasturelands, a breeding habitat with conservation potential considering the U.S. Natural Resource Conservation Service's Working Lands for Wildlife program targeting private lands in the Appalachian Mountains. We located 100 nests of Golden-winged Warblers in pastures in and around the Monongahela National Forest in West Virginia during 2008–2012. Daily nest survival rate (mean ± SE  =  0.962 ± 0.006), clutch size (4.5 ± 0.1), and number of young fledged per nest attempt (2.0 ± 0.2) and successful nest (4.0 ± 0.1) fell within the range of values reported in other parts of the species' range and were not significantly affected by year or the presence/absence of cattle grazing. Classification tree analysis revealed that nests were in denser vegetation (≥52%) and closer to forest edges (<36.0 m) and shrubs (<7.0 cm) than random locations within the male's territory. Successful nests had significantly more woody cover (≥9%) within 1 m than failed nests. Our results suggest that cattle grazing at 1.2–2.4 ha of forage/animal unit with periodic mowing can create and maintain these characteristics without interfering with the nesting of Golden-winged Warblers. High-elevation pasturelands may provide a refuge for remaining populations of Golden-winged Warblers in this region.

Landscape and local effects on occupancy and densities of an endangered wood-warbler in an urbanizing landscape

USGS Publications Warehouse

Reidy, Jennifer; Thompson III, Frank R.; Amundson, Courtney L.; O'Donnell, Lisa

2015-01-01

Landscape composition and habitat structure were important determinants of warbler occupancy and density, and the large intact patches of juniper and mixed forest on BCP (>2100 ha) supported a high density of warblers. Increasing urbanization and fragmentation in the surrounding landscape will likely result in lower breeding density due to loss of juniper and mixed forest and increasing urban land cover and edge.

Continuous, age-related plumage variation in male Kirtland's Warblers

Treesearch

John R. Probst; Deahn M. Donner; Michael A. Bozek

2007-01-01

The ability to age individual birds visually in the field based on plumage variation could provide important demographic and biogeographical information. We describe an approach to infer ages from a distribution of plumage scores of free-ranging male Kirtland's Warblers (Dendroica kinlandii). We assigned ages to males using a scoring scheme (0-...

Comparative nest-site habitat of painted redstarts and red-faced warblers in the Madrean Sky Islands of southeastern Arizona

Treesearch

Joseph L. Ganey; William M. Block; Jamie S. Sanderlin; Jose M. Iniguez

2015-01-01

Conservation of avian species requires understanding their nesting habitat requirements. We compared 3 aspects of habitat at nest sites (topographic characteristics of nest sites, nest placement within nest sites, and canopy stratification within nest sites) of 2 related species of ground-nesting warblers (Red-faced Warblers, Cardellina rubrifrons, n = 17...

Establishing quantitative habitat targets for a "Critically Endangered" neotropical migrant (golden-cheeked warbler Dendroica chrysoparia) during the non-breeding season

Treesearch

David I. King; Carlin C. Chandler; John H. Rappole; Richard B. Chandler; David W. Mehlman

2012-01-01

The Golden-cheeked Warbler Dendroica chrysoparia is a federally endangered Neotropical migrant that inhabits montane pine-oak forests in Mexico and northern Central America during the non-breeding season. Although it is known that Golden-cheeked Warblers are closely associated with ‘encino’ oaks (...

Dynamic emulation modelling for the optimal operation of water systems: an overview

NASA Astrophysics Data System (ADS)

Castelletti, A.; Galelli, S.; Giuliani, M.

2014-12-01

Despite sustained increase in computing power over recent decades, computational limitations remain a major barrier to the effective and systematic use of large-scale, process-based simulation models in rational environmental decision-making. Whereas complex models may provide clear advantages when the goal of the modelling exercise is to enhance our understanding of the natural processes, they introduce problems of model identifiability caused by over-parameterization and suffer from high computational burden when used in management and planning problems. As a result, increasing attention is now being devoted to emulation modelling (or model reduction) as a way of overcoming these limitations. An emulation model, or emulator, is a low-order approximation of the process-based model that can be substituted for it in order to solve high resource-demanding problems. In this talk, an overview of emulation modelling within the context of the optimal operation of water systems will be provided. Particular emphasis will be given to Dynamic Emulation Modelling (DEMo), a special type of model complexity reduction in which the dynamic nature of the original process-based model is preserved, with consequent advantages in a wide range of problems, particularly feedback control problems. This will be contrasted with traditional non-dynamic emulators (e.g. response surface and surrogate models) that have been studied extensively in recent years and are mainly used for planning purposes. A number of real world numerical experiences will be used to support the discussion ranging from multi-outlet water quality control in water reservoir through erosion/sedimentation rebalancing in the operation of run-off-river power plants to salinity control in lake and reservoirs.

Variables associated with detection probability, detection latency, and behavioral responses of Golden-winged Warblers (Vermivora chrysoptera)

USGS Publications Warehouse

Aldinger, Kyle R.; Wood, Petra B.

2015-01-01

Detection probability during point counts and its associated variables are important considerations for bird population monitoring and have implications for conservation planning by influencing population estimates. During 2008–2009, we evaluated variables hypothesized to be associated with detection probability, detection latency, and behavioral responses of male Golden-winged Warblers in pastures in the Monongahela National Forest, West Virginia, USA. This is the first study of male Golden-winged Warbler detection probability, detection latency, or behavioral response based on point-count sampling with known territory locations and identities for all males. During 3-min passive point counts, detection probability decreased as distance to a male's territory and time since sunrise increased. During 3-min point counts with playback, detection probability decreased as distance to a male's territory increased, but remained constant as time since sunrise increased. Detection probability was greater when point counts included type 2 compared with type 1 song playback, particularly during the first 2 min of type 2 song playback. Golden-winged Warblers primarily use type 1 songs (often zee bee bee bee with a higher-pitched first note) in intersexual contexts and type 2 songs (strident, rapid stutter ending with a lower-pitched buzzy note) in intrasexual contexts. Distance to a male's territory, ordinal date, and song playback type were associated with the type of behavioral response to song playback. Overall, ~2 min of type 2 song playback may increase the efficacy of point counts for monitoring populations of Golden-winged Warblers by increasing the conspicuousness of males for visual identification and offsetting the consequences of surveying later in the morning. Because playback may interfere with the ability to detect distant males, it is important to follow playback with a period of passive listening. Our results indicate that even in relatively open pasture

Plumage coloration and reproductive success in male chestnut-sided warblers

Treesearch

David I. King; Richard M. DeGraaf; Curtice R. Griffin

2001-01-01

We studied Chestnut-sided Warblers (Dendroica pensylvanica) to determine whether there exists any relationship between plumage coloration and reproductive success in this species. We observed that males with more extensive chestnut breast coloration initiated nests significantly earlier than males with less chestnut, and had marginally larger...

Influence of summer biogeography on wood warbler stopover abundance

Treesearch

Jeffrey F. Kelly; Rob Smith; Deborah M. Finch; Frank R. Moore; Wang Yong

1999-01-01

We evaluated the effect of summer biogeography of migrant wood warblers (Parulidae) on their stopover abundance. To characterize abundance patterns, we used mist-net capture data from spring and fall migration in the Middle Rio Grande Valley, New Mexico, spring migration on the Gulf Coast of Louisiana, and fall migration on the Gulf Coast of Alabama. To describe the...

Cerulean warbler reproduction, survival, and models of population decline

Treesearch

David A. Buehler; James J. Giocomo; Jason Jones; Paul B. Hamel; Christopher M. Rogers; Tiffany A. Beachy; Dustin W. Varble; Charles P. Nicholson; Kirk L. Roth; JEnnifer Barg; Raleigh J. Robertson; Joseph R. Robb; Kamal Islam

2008-01-01

We present and compare demographic data for cerulean warblers (Dendroica cerulea) from 5 study sites across the range of the species from 1992 to 2006. We conducted field studies to collect data on daily nest survival, nest success, and young fledged per successful nest, and we used data to estimate fecundity. Daily nest survival, nest success, young...

Research on golden-winged warblers: recent progress and current needs

Treesearch

Henry M. Streby; Ronald W. Rohrbaugh; David A. Buehler; David E. Andersen; Rachel Vallender; David I. King; Tom Will

2016-01-01

Considerable advances have been made in knowledge about Golden-winged Warblers (Vermivora chrysoptera) in the past decade. Recent employment of molecular analysis, stable-isotope analysis, telemetry-based monitoring of survival and behavior, and spatially explicit modeling techniques have added to, and revised, an already broad base of published...

Evaluating Emulation-based Models of Distributed Computing Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Stephen T.; Gabert, Kasimir G.; Tarman, Thomas D.

Emulation-based models of distributed computing systems are collections of virtual ma- chines, virtual networks, and other emulation components configured to stand in for oper- ational systems when performing experimental science, training, analysis of design alterna- tives, test and evaluation, or idea generation. As with any tool, we should carefully evaluate whether our uses of emulation-based models are appropriate and justified. Otherwise, we run the risk of using a model incorrectly and creating meaningless results. The variety of uses of emulation-based models each have their own goals and deserve thoughtful evaluation. In this paper, we enumerate some of these uses andmore » describe approaches that one can take to build an evidence-based case that a use of an emulation-based model is credible. Predictive uses of emulation-based models, where we expect a model to tell us something true about the real world, set the bar especially high and the principal evaluation method, called validation , is comensurately rigorous. We spend the majority of our time describing and demonstrating the validation of a simple predictive model using a well-established methodology inherited from decades of development in the compuational science and engineering community.« less

Validation techniques for fault emulation of SRAM-based FPGAs

DOE PAGES

Quinn, Heather; Wirthlin, Michael

2015-08-07

A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA inmore » a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this study we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.« less

Statistical Emulator for Expensive Classification Simulators

NASA Technical Reports Server (NTRS)

Ross, Jerret; Samareh, Jamshid A.

2016-01-01

Expensive simulators prevent any kind of meaningful analysis to be performed on the phenomena they model. To get around this problem the concept of using a statistical emulator as a surrogate representation of the simulator was introduced in the 1980's. Presently, simulators have become more and more complex and as a result running a single example on these simulators is very expensive and can take days to weeks or even months. Many new techniques have been introduced, termed criteria, which sequentially select the next best (most informative to the emulator) point that should be run on the simulator. These criteria methods allow for the creation of an emulator with only a small number of simulator runs. We follow and extend this framework to expensive classification simulators.

Dynamic climate emulators for solar geoengineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacMartin, Douglas G.; Kravitz, Ben

2016-12-22

Climate emulators trained on existing simulations can be used to project project the climate effects that result from different possible future pathways of anthropogenic forcing, without further relying on general circulation model (GCM) simulations. We extend this idea to include different amounts of solar geoengineering in addition to different pathways of greenhouse gas concentrations, by training emulators from a multi-model ensemble of simulations from the Geoengineering Model Intercomparison Project (GeoMIP). The emulator is trained on the abrupt 4 × CO 2 and a compensating solar reduction simulation (G1), and evaluated by comparing predictions against a simulated 1 % per yearmore » CO 2 increase and a similarly smaller solar reduction (G2). We find reasonable agreement in most models for predicting changes in temperature and precipitation (including regional effects), and annual-mean Northern Hemisphere sea ice extent, with the difference between simulation and prediction typically being smaller than natural variability. This verifies that the linearity assumption used in constructing the emulator is sufficient for these variables over the range of forcing considered. Annual-minimum Northern Hemisphere sea ice extent is less well predicted, indicating a limit to the linearity assumption.« less

The cerulean warbler in Morgan-Monroe and Yellowwood State Forests, Indiana: pre-treatment data on abundance and spatial characteristics of territories

Treesearch

Kamal Islam; Kyle J. Kaminski; Margaret M. MacNeil; Lila Prichard. Young

2013-01-01

The cerulean warbler (Setophaga cerulea) is a small Neotropical migrant songbird that is currently experiencing population declines. We monitored the number of cerulean warblers, as well as size and spatial attributes of territories, before two methods of silvicultural treatments took place in six of nine study units involved in the Hardwood...

Temporal and spatial variation of hematozoans in Scandinavian willow warblers.

PubMed

Bensch, Staffan; Akesson, Susanne

2003-04-01

We examined temporal and geographical distribution of Haemoproteus sp. and Plasmodium sp. parasites in Swedish willow warblers, Phylloscopus trochilus. Parasite lineages were detected with molecular methods in 556 birds from 41 sites distributed at distances up to 1,500 km. Two mitochondrial lineages of Haemoproteus sp. were detected, WW1 in 56 birds and WW2 in 75 birds, that differed by 5.2% sequence divergence. We discuss the reasons behind the observed pattern of variation and identify 3 possible causes: (1) variation in the geographic distribution of the vector species, (2) the degree of parasite sharing with other bird species coexisting with the willow warbler, and (3) timing of transmission. Our results support a fundamental and rarely tested assumption of the now classical Hamilton-Zuk hypothesis of sexual selection, namely, that these parasites vary in both time and space. Such fluctuations of parasites and the selection pressure they supposedly impose on the host population are likely to maintain variation in immune system genes in the host population.

Generic Software for Emulating Multiprocessor Architectures.

DTIC Science & Technology

1985-05-01

RD-A157 662 GENERIC SOFTWARE FOR EMULATING MULTIPROCESSOR 1/2 AlRCHITECTURES(J) MASSACHUSETTS INST OF TECH CAMBRIDGE U LRS LAB FOR COMPUTER SCIENCE R...AREA & WORK UNIT NUMBERS MIT Laboratory for Computer Science 545 Technology Square Cambridge, MA 02139 ____________ I I. CONTROLLING OFFICE NAME AND...aide If neceeasy end Identify by block number) Computer architecture, emulation, simulation, dataf low 20. ABSTRACT (Continue an reverse slde It

Metabolizable energy in Chinese tallow fruit for Yellow-rumped Warblers, Northern Cardinals, and American Robins

USGS Publications Warehouse

Baldwin, M.J.; Barrow, W.C.; Jeske, C.; Rohwer, F.C.

2008-01-01

The invasive exotic Chinese tallow tree (Triadica sebifera) produces an abundant fruit crop, which is primarily bird-dispersed. The fruit pulp of tallow is lipid-rich, high in saturated fatty acids, and consumed by many bird species. Long-chained fatty acids can be difficult for many birds to digest and we investigated the ability of tallow consumers to assimilate energy in the pulp. We used the total collection method and compared apparent metabolizable energy (AME) of tallow fruit for three species of birds with differing fruit composition in their natural diets. All birds exhibited nitrogen deficits and lost body mass during the trials. Northern Cardinals (Cardinalis cardinalis) lost more mass (8.73%/day) than Yellow-rumped Warblers (Dendroica coronata) (5.29%/day) and American Robins (Turdus migratorius) (5.48%/day), and had larger nitrogen deficits (-120.1 mg N/g diet) than both species as well (-36.4 mg N/g diet and -68.9 mg N/g diet, respectively). Food intake relative to metabolic body mass was highest in Yellow-rumped Warblers (0.70 g-dry/g 0.75??day). Northern Cardinal and American Robin food intake was lower and did not differ from each other (both species: 0.13 g-dry/g 0.75??day). Nitrogen corrected values of AME were used to make species comparisons. Yellow-rumped-Warblers exhibited the highest values of AME (30.00 kJ/g), followed by American Robins (23.90 kJ/g), and Northern Cardinals (14.34 kJ/g). We suggest tallow may be an important winter food source for Yellow-rumped Warblers where their ranges overlap.

Pairing success of Kirtland's warblers in marginal vs. suitable habitat

Treesearch

John R. Probst; Jack P. Hayes

1987-01-01

We compared pairing success of male Kirtland's Warblers (Dendroica kirtlandii) in different habitats to test the hypothesis that a lower proportion of males in marginal habitat are mated. Fewer than 60% of the males in marginal habitat were paired, but 95% of the males in suitable habitat were paired. We estimated the overall pairing success of...

Demographic rates of Golden-cheeked Warblers in an urbanizing woodland preserve

Treesearch

Jennifer L. Reidy; Frank R. Thompson; Grant M. Connette; Lisa O' Donnell

2018-01-01

Knowledge of demographics is important in conservation planning for endangered species. We monitored the endangered Golden-cheeked Warbler (Setophaga chrysoparia) at a large, discontinuous preserve in an urbanizing landscape in central Texas, USA, to estimate survival and productivity. We estimated adult male survival using a spatial Cormack-Jolly-...

Evaluation of Electromechanical Systems Dynamically Emulating a Candidate Hydrokinetic Turbine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cavagnaro, Robert J.; Neely, Jason C.; Fay, Franois-Xavier

The use of controllable motor-generator sets to emulate the dynamics of a hydrokinetic turbine is evaluated as an alternative to field testing a prototype. The emulator control dynamic equations are presented, methods for scaling turbine parameters are examined, and experimental results are presented from three electromechanical emulation machines (EEMs) programmed to emulate the same vertical-axis fixed-pitch turbine. Although hardware platforms and control implementations varied, results show that each EEM is successful in emulating the turbine model, thus demonstrating the general feasibility of the approach. However, performance of motor control under torque command, current command or speed command differed. In onemore » of the EEMs evaluated, the power take off controller tracks the maximum power-point of the turbine in response to turbulence. Utilizing realistic inflow conditions and control laws, the emulator dynamic speed response is shown to agree well at low frequencies with numerical simulation but to deviate at high frequencies.« less

Evaluation of Electromechanical Systems Dynamically Emulating a Candidate Hydrokinetic Turbine

DOE PAGES

Cavagnaro, Robert J.; Neely, Jason C.; Fay, Franois-Xavier; ...

2016-11-06

The use of controllable motor-generator sets to emulate the dynamics of a hydrokinetic turbine is evaluated as an alternative to field testing a prototype. The emulator control dynamic equations are presented, methods for scaling turbine parameters are examined, and experimental results are presented from three electromechanical emulation machines (EEMs) programmed to emulate the same vertical-axis fixed-pitch turbine. Although hardware platforms and control implementations varied, results show that each EEM is successful in emulating the turbine model, thus demonstrating the general feasibility of the approach. However, performance of motor control under torque command, current command or speed command differed. In onemore » of the EEMs evaluated, the power take off controller tracks the maximum power-point of the turbine in response to turbulence. Utilizing realistic inflow conditions and control laws, the emulator dynamic speed response is shown to agree well at low frequencies with numerical simulation but to deviate at high frequencies.« less

Computer-Graphics Emulation of Chemical Instrumentation: Absorption Spectrophotometers.

ERIC Educational Resources Information Center

Gilbert, D. D.; And Others

1982-01-01

Describes interactive, computer-graphics program emulating behavior of high resolution, ultraviolet-visible analog recording spectrophotometer. Graphics terminal behaves as recording absorption spectrophotometer. Objective of the emulation is study of optimization of the instrument to yield accurate absorption spectra, including…

Satellite Communication Hardware Emulation System (SCHES)

NASA Technical Reports Server (NTRS)

Kaplan, Ted

1993-01-01

Satellite Communication Hardware Emulator System (SCHES) is a powerful simulator that emulates the hardware used in TDRSS links. SCHES is a true bit-by-bit simulator that models communications hardware accurately enough to be used as a verification mechanism for actual hardware tests on user spacecraft. As a credit to its modular design, SCHES is easily configurable to model any user satellite communication link, though some development may be required to tailor existing software to user specific hardware.

Head-scratching method of the Swainson's warbler

USGS Publications Warehouse

Meanley, Brooke

1970-01-01

Ficken and Ficken (Auk, 85: 136, 1968) suggest that the "Head-scratching method may prove a valuable addition to the set of complex characters that can be used in defining genera," and that field observers should continue to fill gaps in our knowledge of this behavior. In the course of a series of observations of Swainson's Warblers (Limnothlypis swainsonii) in the Dismal Swamp, Virginia, I saw head-scratching in three individuals, four times in one, three in another, and once in the third. All three birds used the direct method, bringing the foot forward and under the wing.

Intersexual and temporal variation in foraging ecology of prothonotary warblers during the breeding season

USGS Publications Warehouse

Petit, L.J.; Petit, D.R.; Petit, K.E.; Fleming, W.J.

1990-01-01

We studied foraging ecology of Prothonotary Warblers (Protonotaria citrea) over four breeding seasons to determine if this species exhibited sex-specific or temporal variation in foraging behavior. Significant differences between sexes during the prenestling period were found for foraging height and substrate height (foraging method, plant species/substrate, perch diameter, horizontal location from trunk, and prey location were not significantly different). During the nestling period, this divergence between sexes was evident for foraging height, substrate height, substrate / tree species, and prey location. Additionally, male warblers significantly altered their behavior for all seven foraging variables between the two periods, whereas females exhibited changes similar to those of males for five of the foraging variables. This parallel shift suggests a strong behavioral response by both sexes to proximate factors (such as vegetation structure, and prey abundance and distribution) that varied throughout the breeding season. Sex-specific foraging behavior during the prenestling period was best explained by differences in reproductive responsibilities rather than by the theory of intersexual competition for limited resources. During the nestling period, neither hypothesis by itself explained foraging divergences adequately. However, when integrated with the temporal responses of the warblers to changes in prey availability, reproductive responsibilities seemed to be of primary importance in explaining intersexual niche partitioning during the nestling period. We emphasize the importance of considering both intersexual and intraseasonal variation when quantifying a species' foraging ecology.

Mate guarding in the Seychelles warbler is energetically costly and adjusted to paternity risk.

PubMed

Komdeur, J

2001-10-22

Males may increase their fitness through extra-pair copulations (copulations outside the pair bond) that result in extra-pair fertilizations, but also risk lost paternity when they leave their own mate unguarded. The fitness costs of cuckoldry for Seychelles warblers (Acrocephalus sechellensis) are considerable because warblers have a single-egg clutch and, given the short breeding season, no time for a successful replacement clutch. Neighbouring males are the primary threat to a male's genetic paternity. Males minimize their loss of paternity by guarding their mates to prevent them from having extra-pair copulations during their fertile period. Here, I provide experimental evidence that mate-guarding behaviour is energetically costly and that the expression of this trade-off is adjusted to paternity risk (local male density). Free-living males that were induced to reduce mate guarding spent significantly more time foraging and gained significantly better body condition than control males. The larger the reduction in mate guarding, the more pronounced was the increase in foraging and body condition (accounting for food availability). An experimental increase in paternity risk resulted in an increase in mate-guarding intensity and a decrease in foraging and body condition, and vice versa. This is examined using both cross-sectional and longitudinal data. This study on the Seychelles warbler offers experimental evidence that mate guarding is energetically costly and adjusted to paternity risk.

Design of BLDCM emulator for transmission control units

NASA Astrophysics Data System (ADS)

Liu, Chang; He, Yongyi; Zhang, Bodong

2018-04-01

According to the testing requirements of the transmission control unit, a brushless DC motor emulating system is designed based on motor simulation and power hardware-in-the-loop. The discrete motor model is established and a real-time numerical method is designed to solve the motor states. The motor emulator directly interacts with power stage of the transmission control unit using a power-efficient circuit topology and is compatible with sensor-less control. Experiments on a laboratory prototype help to verify that the system can emulate the real motor currents and voltages whenever the motor is starting up or suddenly loaded.

Landscape-level forest cover is a predictor of cerulean warbler abundance

Treesearch

Frank R., III Thompson; Mark B. Robbins; Jane A. Fitzgerald

2012-01-01

We examined support for the hypothesis that abundance of Cerulean Warblers (Setophaga cerulea) increases with percentage of bottomland and upland forest, and decreases with percentage of developed land at a local-habitat scale (within a 250-m buffer) and increases with percentage of all forest at a landscape scale (within a 10-km buffer). We...

Flash LIDAR Emulator for HIL Simulation

NASA Technical Reports Server (NTRS)

Brewster, Paul F.

2010-01-01

NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) project is building a system for detecting hazards and automatically landing controlled vehicles safely anywhere on the Moon. The Flash Light Detection And Ranging (LIDAR) sensor is used to create on-the-fly a 3D map of the unknown terrain for hazard detection. As part of the ALHAT project, a hardware-in-the-loop (HIL) simulation testbed was developed to test the data processing, guidance, and navigation algorithms in real-time to prove their feasibility for flight. Replacing the Flash LIDAR camera with an emulator in the testbed provided a cheaper, safer, more feasible way to test the algorithms in a controlled environment. This emulator must have the same hardware interfaces as the LIDAR camera, have the same performance characteristics, and produce images similar in quality to the camera. This presentation describes the issues involved and the techniques used to create a real-time flash LIDAR emulator to support HIL simulation.

Autumn orientation behaviour of paddyfield warblers, Acrocephalus agricola, from a recently expanded breeding range on the western Black Sea coast.

PubMed

Zehtindjiev, Pavel; Ilieva, Mihaela; Akesson, Susanne

2010-10-01

The paddyfield warbler, Acrocephalus agricola, has extended its breeding range from Central Asia to the western Black Sea coast. The Balkan population offers a unique chance to test the effect of breeding range expansion on the genetically programmed migratory direction. We studied 21 paddyfield warblers at Durankulak Lake, NE Bulgaria, by recording their autumn migratory orientation in circular orientation cages. Our data show that the preferred migratory orientation is directed along a NE-SW axis. Paddyfield warblers seem to avoid direct crossing of the Black Sea by following the western coast. The mean bearing was parallel to the nearest coastline and corresponds to the direction of the historical breeding range expansion of the species. In our experiment many individuals showed south-western orientation in autumn, a course which would potentially lead the birds to exploratory movements outside the current breeding range. An axial orientation response has been often shown in circular cage tests, and can be due to factors such as coastal orientation or reverse orientation triggered by the physiological condition of some individuals. However, it might also be one of the driving mechanisms for range expansion. Hence, we can expect the future expansion of Balkan paddyfield warblers to continue towards south-west. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Development of Wave Turbine Emulator in a Laboratory Environment

NASA Astrophysics Data System (ADS)

Vinatha, U.; Vittal K, P.

2013-07-01

Wave turbine emulator (WTE) is an important equipment for developing wave energy conversion system. The emulator reflects the actual behavior of the wave turbine by reproducing the characteristics of real wave turbine without reliance on natural wave resources and actual wave turbine. It offers a controllable test environment that allows the evaluation and improvement of control schemes for electric generators. The emulator can be used for research applications to drive an electrical generator in a similar way as a practical wave turbine. This article presents the development of a WTE in a laboratory environment and studies on the behavior of electrical generator coupled to the emulator. The structure of a WTE consists of a PC where the characteristics of the turbine are implemented, ac drive to emulate the turbine rotor, feedback mechanism from the drive and power electronic equipment to control the drive. The feedback signal is acquired by the PC through an A/D converter, and the signal for driving the power electronic device comes from the PC through a D/A converter.

The Chewing Lice (Insecta, Phthiraptera) Fauna of the Swainson's Warbler, Limnothlypis swainsonii (Aves, Parulidae).

PubMed

Valim, Michel P; Reiley, Bryan M

2015-09-01

We examined Swainson's warblers (Limnothlypis swainsonii (Audubon, 1834), Aves: Parulidae) for lice fauna during 2 yr at three study sites in Arkansas, USA. A total of 66 individuals were examined; eight birds (10.6%) were parasitized with 16 lice of two new species belonging to two genera Myrsidea Waterson, 1915 (Amblycera: Menoponidae) and Brueelia Kéler, 1936 (Ischnocera: Philopteridae). Parasitological parameter data are given on the prevalence of lice on Swainson's warblers. Species descriptions and illustrations are provided for Myrsidea bensoni sp. nov. and Brueelia limnothlypiae sp. nov.; including a key for females of the genus Myrsidea that parasitize Parulidae (Passeriformes). © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Cerulean Warbler (Setophaga cerulea) spring migration stopover in northern Middle America

Treesearch

Melinda J. Welton; David L. Anderson; Gabriel J. Colorado; Paul B. Hamel; Diego Calderón-F.

2012-01-01

The Cerulean Warbler (Setophaga cerulea) has one of the longest migrations of any small passerine, traveling approximately 4,000 km between breeding grounds in eastern North America and nonbreeding residency in northern South America. However, unlike many migratory birds, little is known about this aspect of the ecology of this species. In 2004 –...

Vegetation of a Kirtland's warbler breeding area and 10 nest sites

Treesearch

Richard R. Buech

1980-01-01

Early observers noted that the Kirtland's Warbler (Dendroica kirtlandii) required young jack pine (Pinus banksiana) stands of fire origin (Wood 1904, 1926; Barrows 1921; Leopold 1924; Wing 1933). Leopold (1924) observed that they nested in stands about 1 to 3 m tall and that the nest was usually within 3 dm (1dm = 0.1m) of the...

Case-based reasoning emulation of persons for wheelchair navigation.

PubMed

Peula, Jose Manuel; Urdiales, Cristina; Herrero, Ignacio; Fernandez-Carmona, Manuel; Sandoval, Francisco

2012-10-01

Testing is a key stage in system development, particularly in systems such as a wheelchair, in which the final user is typically a disabled person. These systems have stringent safety requirements, requiring major testing with many different individuals. The best would be to have the wheelchair tested by many different end users, as each disability affects driving skills in a different way. Unfortunately, from a practical point of view it is difficult to engage end users as beta testers. Hence, testing often relies on simulations. Naturally, these simulations need to be as realistic as possible to make the system robust and safe before real tests can be accomplished. This work presents a tool to automatically test wheelchairs through realistic emulation of different wheelchair users. Our approach is based on extracting meaningful data from real users driving a power wheelchair autonomously. This data is then used to train a case-based reasoning (CBR) system that captures the specifics of the driver via learning. The resulting case-base is then used to emulate the driving behavior of that specific person in more complex situations or when a new assistive algorithm needs to be tested. CBR returns user's motion commands appropriate for each specific situation to add the human component to shared control systems. The proposed system has been used to emulate several power wheelchair users presenting different disabilities. Data to create this emulation was obtained from previous wheelchair navigation experiments with 35 volunteer in-patients presenting different degrees of disability. CBR was trained with a limited number of scenarios for each volunteer. Results proved that: (i) emulated and real users returned similar paths in the same scenario (maximum and mean path deviations are equal to 23 and 10cm, respectively) and similar efficiency; (ii) we established the generality of our approach taking a new path not present in the training traces; (iii) the emulated user

Evaluating outcomes of management targeting the recovery of a migratory songbird of conservation concern

USGS Publications Warehouse

Streby, Henry M.; Kramer, Gunnar R.; Peterson, Sean M.; Andersen, David

2018-01-01

Assessing outcomes of habitat management is critical for informing and adapting conservation plans. From 2013 – 2019, a multi-stage management initiative aims to create >25,000 ha of shrubland and early-successional vegetation to benefit Golden-winged Warblers (Vermivora chrysoptera) in managed forested landscapes of the western Great Lakes region. We studied a dense breeding population of Golden-winged Warblers at Rice Lake National Wildlife Refuge (NWR) in Minnesota, USA, where shrubs and young trees were sheared during the winter of 2014-2015 in a single treatment supported in part by the American Bird Conservancy (ABC) and in part by other funding source(s) to benefit Golden-winged Warblers and other species associated with young forest [e.g., American Woodcock (Scalopax minor)] and as part of maintenance of early successional forest cover on the refuge.

Occurrence of the Connecticut Warbler increases with size of patches of coniferous forest

EPA Science Inventory

The Connecticut Warbler (Oporornis agilis) is a rare and declining Neotropical migrant that breeds in north-central United States and south-central Canada. To better understand the habitat needs of this species, we analysed habitat and landscape at three spatial scales (buffer ra...

Advanced Machine Learning Emulators of Radiative Transfer Models

NASA Astrophysics Data System (ADS)

Camps-Valls, G.; Verrelst, J.; Martino, L.; Vicent, J.

2017-12-01

Physically-based model inversion methodologies are based on physical laws and established cause-effect relationships. A plethora of remote sensing applications rely on the physical inversion of a Radiative Transfer Model (RTM), which lead to physically meaningful bio-geo-physical parameter estimates. The process is however computationally expensive, needs expert knowledge for both the selection of the RTM, its parametrization and the the look-up table generation, as well as its inversion. Mimicking complex codes with statistical nonlinear machine learning algorithms has become the natural alternative very recently. Emulators are statistical constructs able to approximate the RTM, although at a fraction of the computational cost, providing an estimation of uncertainty, and estimations of the gradient or finite integral forms. We review the field and recent advances of emulation of RTMs with machine learning models. We posit Gaussian processes (GPs) as the proper framework to tackle the problem. Furthermore, we introduce an automatic methodology to construct emulators for costly RTMs. The Automatic Gaussian Process Emulator (AGAPE) methodology combines the interpolation capabilities of GPs with the accurate design of an acquisition function that favours sampling in low density regions and flatness of the interpolation function. We illustrate the good capabilities of our emulators in toy examples, leaf and canopy levels PROSPECT and PROSAIL RTMs, and for the construction of an optimal look-up-table for atmospheric correction based on MODTRAN5.

Conservation perspectives: Review of new science and primary threats to golden-winged warblers

Treesearch

Ronald W. Rohrbaugh; David A. Buehler; Sara Barker Swarthout; David I. King; Jeffrey L. Larkin; Kenneth V. Rosenberg; Amber M. Roth; Rachel Vallender; Tom Will

2016-01-01

In this penultimate chapter, we examine new perspectives on ecology of Golden-winged Warblers (Vermivora chrysoptera), review primary population- level threats, and offer conservation recommendations. Adequate forest cover and patchlevel habitat configuration are important for successful reproduction and to buffer against negative interactions with...

Microsatellite DNA markers for delineating population structure and kinship among the endangered Kirtland's warbler (Dendroica kirtlandii)

USGS Publications Warehouse

King, T.L.; Eackles, M.S.; Henderson, A.P.; Bocetti, Carol I.; Currie, D.; Wunderle, J.M.

2005-01-01

We document the isolation and characterization of 23 microsatellite DNA markers for the endangered Kirtland's warbler (Dendroica kirtlandii), a Nearctic/Neotropical migrant passerine. This suite of markers revealed moderate to high levels of allelic diversity (averaging 7.7 alleles per locus) and heterozygosity (averaging 72%). Genotypic frequencies at 22 of 23 (95%) markers conformed to Hardy-Weinberg equilibrium expectations, and no linkage disequilibrium was observed in blood samples taken from 14 warblers found on the wintering grounds in the Bahamas archipelago. Multilocus genotypes resulting from this suite of markers should reduce the amount of resources required for initiating new genetic studies assessing breeding structure, parentage, demographics, and individual-level ecological interactions for D. kirtlandii. ?? 2005 Blackwell Publishing Ltd.

Memristor emulator causes dissimilarity on a coupled memristive systems

NASA Astrophysics Data System (ADS)

Sabarathinam, S.; Prasad, Awadhesh

2018-04-01

The memristor is known as abasic fourth passive solid state circuit element. Itgaining increasing attention to create the next generation electronic devices commonly used as fundamental chaotic circuit although often arbitrary (typically piecewise linear or cubic) fluxcharge characteristics. In thispresent work, the causes of the memristor emulator studied in a coupled memristive chaoticoscillator for the first time. We confirm that the emulator that allows synchronization between theoscillators and cause the dissimilarity between the systems when increasing the couplingstrength, and co-efficient of the memristor emulator. The detailed statistical analysis was performed to confirm such phenomenon.

Insights into Wilson's Warbler migration from analyses of hydrogen stable-isotope ratios

Treesearch

Jeffrey F. Kelly; Viorel Atudorei; Zachary D. Sharp; Deborah M. Finch

2002-01-01

Our ability to link the breeding locations of individual passerines to migration stopover sites and wintering locations is limited. Stable isotopes of hydrogen contained in bird feathers have recently shown potential in this regard. We measured hydrogen stable-isotope ratios (deltaD) of feathers from breeding, migrating, and wintering Wilson's Warblers. Analyses...

System on a Chip Real-Time Emulation (SOCRE)

DTIC Science & Technology

2006-09-01

code ) i Table of Contents Preface...emulation platform included LDPC decoders, A/V and radio applications Port BEE flow to Emulation Platforms, SOC Technologies One of the key tasks of the...Once the design has been described within Simulink, the designer runs the BEE design flow within Matlab using the bee_xps interface. At this point

No evidence of an MHC-based female mating preference in great reed warblers.

PubMed

Westerdahl, Helena

2004-08-01

Female mate-choice based on genetic compatibility is an area of growing interest. The major histocompatibility complex (MHC) genes are likely candidates for such mate-choice since these highly polymorphic genes may both increase offspring viability and also provide direct cues for mate-choice. In great reed warblers, females actively choose a breeding partner out of a handful of males that they visit and evaluate; thus, female preference for compatible or heterozygous MHC genes could have evolved. Here, I investigate whether great reed warbler females preferentially mate with males with dissimilar MHC class I alleles or with males that are heterozygous at MHC class I. Despite favourable conditions, a thorough screening method and a large sample size, there was no evidence of an MHC-based female mating preference based on either genetic compatibility or heterozygosity in this population. Power analyses of the data sets revealed that relatively small differences (15% and 8%, respectively) between true and random pairs should have been detected. Copyright 2004 Blackwell Publishing Ltd

UPEML: a machine-portable CDC Update emulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehlhorn, T.A.; Young, M.F.

1984-12-01

UPEML is a machine-portable CDC Update emulation program. UPEML is written in ANSI standard Fortran-77 and is relatively simple and compact. It is capable of emulating a significant subset of the standard CDC Update functions including program library creation and subsequent modification. Machine-portability is an essential attribute of UPEML. It was written primarily to facilitate the use of CDC-based scientific packages on alternate computer systems such as the VAX 11/780 and the IBM 3081.

Factors affecting golden-cheeked warbler nest survival in urban and rural landscapes

Treesearch

Jenifer L. Reidy; Frank R. Thompson; Rebecca G. Peak

2009-01-01

We evaluated hypotheses concerning temporal, landscape, and habitat effects on nest survival of golden-cheeked warblers (Dendroica chrysoparia) in an urban and a rural landscape during the breeding seasons of 2005 and 2006 in central Texas, USA. We found support for temporal effects of year and cubic effect of date and included them in candidate...

Emulating Industrial Control System Field Devices Using Gumstix Technology

DTIC Science & Technology

2012-06-01

EMULATING INDUSTRIAL CONTROL SYSTEM FIELD DEVICES USING GUMSTIX TECHNOLOGY THESIS Dustin J...APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. The views expressed in this thesis are those of the...EMULATING INDUSTRIAL CONTROL SYSTEM FIELD DEVICES USING GUMSTIX TECHNOLOGY THESIS Presented to the Faculty Department of

Development of the CELSS Emulator at NASA JSC

NASA Technical Reports Server (NTRS)

Cullingford, Hatice S.

1989-01-01

The Controlled Ecological Life Support System (CELSS) Emulator is under development at the NASA Johnson Space Center (JSC) with the purpose to investigate computer simulations of integrated CELSS operations involving humans, plants, and process machinery. This paper describes Version 1.0 of the CELSS Emulator that was initiated in 1988 on the JSC Multi Purpose Applications Console Test Bed as the simulation framework. The run module of the simulation system now contains a CELSS model called BLSS. The CELSS Emulator makes it possible to generate model data sets, store libraries of results for further analysis, and also display plots of model variables as a function of time. The progress of the project is presented with sample test runs and simulation display pages.

The TAVERNS emulator: An Ada simulation of the space station data communications network and software development environment

NASA Technical Reports Server (NTRS)

Howes, Norman R.

1986-01-01

The Space Station DMS (Data Management System) is the onboard component of the Space Station Information System (SSIS) that includes the computers, networks and software that support the various core and payload subsystems of the Space Station. TAVERNS (Test And Validation Environment for Remote Networked Systems) is a distributed approach for development and validation of application software for Space Station. The TAVERNS concept assumes that the different subsystems will be developed by different contractors who may be geographically separated. The TAVERNS Emulator is an Ada simulation of a TAVERNS on the ASD VAX. The software services described in the DMS Test Bed User's Manual are being emulated on the VAX together with simulations of some of the core subsystems and a simulation of the DCN. The TAVERNS Emulator will be accessible remotely from any VAX that can communicate with the ASD VAX.

Real-time emulation of neural images in the outer retinal circuit.

PubMed

Hasegawa, Jun; Yagi, Tetsuya

2008-12-01

We describe a novel real-time system that emulates the architecture and functionality of the vertebrate retina. This system reconstructs the neural images formed by the retinal neurons in real time by using a combination of analog and digital systems consisting of a neuromorphic silicon retina chip, a field-programmable gate array, and a digital computer. While the silicon retina carries out the spatial filtering of input images instantaneously, using the embedded resistive networks that emulate the receptive field structure of the outer retinal neurons, the digital computer carries out the temporal filtering of the spatially filtered images to emulate the dynamical properties of the outer retinal circuits. The emulations of the neural image, including 128 x 128 bipolar cells, are carried out at a frame rate of 62.5 Hz. The emulation of the response to the Hermann grid and a spot of light and an annulus of lights has demonstrated that the system responds as expected by previous physiological and psychophysical observations. Furthermore, the emulated dynamics of neural images in response to natural scenes revealed the complex nature of retinal neuron activity. We have concluded that the system reflects the spatiotemporal responses of bipolar cells in the vertebrate retina. The proposed emulation system is expected to aid in understanding the visual computation in the retina and the brain.

Panel Flutter Emulation Using a Few Concentrated Forces

NASA Astrophysics Data System (ADS)

Dhital, Kailash; Han, Jae-Hung

2018-04-01

The objective of this paper is to study the feasibility of panel flutter emulation using a few concentrated forces. The concentrated forces are considered to be equivalent to aerodynamic forces. The equivalence is carried out using surface spline method and principle of virtual work. The structural modeling of the plate is based on the classical plate theory and the aerodynamic modeling is based on the piston theory. The present approach differs from the linear panel flutter analysis in scheming the modal aerodynamics forces with unchanged structural properties. The solutions for the flutter problem are obtained numerically using the standard eigenvalue procedure. A few concentrated forces were considered with an optimization effort to decide their optimal locations. The optimization process is based on minimizing the error between the flutter bounds from emulated and linear flutter analysis method. The emulated flutter results for the square plate of four different boundary conditions using six concentrated forces are obtained with minimal error to the reference value. The results demonstrated the workability and viability of using concentrated forces in emulating real panel flutter. In addition, the paper includes the parametric studies of linear panel flutter whose proper literatures are not available.

Design of testbed and emulation tools

NASA Technical Reports Server (NTRS)

Lundstrom, S. F.; Flynn, M. J.

1986-01-01

The research summarized was concerned with the design of testbed and emulation tools suitable to assist in projecting, with reasonable accuracy, the expected performance of highly concurrent computing systems on large, complete applications. Such testbed and emulation tools are intended for the eventual use of those exploring new concurrent system architectures and organizations, either as users or as designers of such systems. While a range of alternatives was considered, a software based set of hierarchical tools was chosen to provide maximum flexibility, to ease in moving to new computers as technology improves and to take advantage of the inherent reliability and availability of commercially available computing systems.

Hardware and Software Integration to Support Real-Time Space Link Emulation

NASA Technical Reports Server (NTRS)

Murawski, Robert; Bhasin, Kul; Bittner, David; Sweet, Aaron; Coulter, Rachel; Schwab, Devin

2012-01-01

Prior to operational use, communications hardware and software must be thoroughly tested and verified. In space-link communications, field testing equipment can be prohibitively expensive and cannot test to non-ideal situations. In this paper, we show how software and hardware emulation tools can be used to accurately model the characteristics of a satellite communication channel in a lab environment. We describe some of the challenges associated with developing an emulation lab and present results to demonstrate the channel modeling. We then show how network emulation software can be used to extend a hardware emulation model without requiring additional network and channel simulation hardware.

Hardware and Software Integration to Support Real-Time Space-Link Emulation

NASA Technical Reports Server (NTRS)

Murawski, Robert; Bhasin, Kul; Bittner, David

2012-01-01

Prior to operational use, communications hardware and software must be thoroughly tested and verified. In space-link communications, field testing equipment can be prohibitively expensive and cannot test to non-ideal situations. In this paper, we show how software and hardware emulation tools can be used to accurately model the characteristics of a satellite communication channel in a lab environment. We describe some of the challenges associated with developing an emulation lab and present results to demonstrate the channel modeling. We then show how network emulation software can be used to extend a hardware emulation model without requiring additional network and channel simulation hardware.

QERx- A Faster than Real-Time Emulator for Space Processors

NASA Astrophysics Data System (ADS)

Carvalho, B.; Pidgeon, A.; Robinson, P.

2012-08-01

Developing software for space systems is challenging. Especially because, in order to be sure it can cope with the harshness of the environment and the imperative requirements and constrains imposed by the platform were it will run, it needs to be tested exhaustively. Software Validation Facilities (SVF) are known to the industry and developers, and provide the means to run the On-Board Software (OBSW) in a realistic environment, allowing the development team to debug and test the software.But the challenge is to be able to keep up with the performance of the new processors (LEON2 and LEON3), which need to be emulated within the SVF. Such processor emulators are also used in Operational Simulators, used to support mission preparation and train mission operators. These simulators mimic the satellite and its behaviour, as realistically as possible. For test/operational efficiency reasons and because they will need to interact with external systems, both these uses cases require the processor emulators to provide real-time, or faster, performance.It is known to the industry that the performance of previously available emulators is not enough to cope with the performance of the new processors available in the market. SciSys approached this problem with dynamic translation technology trying to keep costs down by avoiding a hardware solution and keeping the integration flexibility of full software emulation.SciSys presented “QERx: A High Performance Emulator for Software Validation and Simulations” [1], in a previous DASIA event. Since then that idea has evolved and QERx has been successfully validated. SciSys is now presenting QERx as a product that can be tailored to fit different emulation needs. This paper will present QERx latest developments and current status.

Breeding population density and habitat use of Swainson's warblers in a Georgia floodplain forest

USGS Publications Warehouse

Wright, E.A.

2002-01-01

I examined density and habitat use of a Swainson's Warbler (Limnothlypis swainsonii) breeding population in Georgia. This songbird species is inadequately monitored, and may be declining due to anthropogenic alteration of floodplain forest breeding habitats. I used distance sampling methods to estimate density, finding 9.4 singing males/ha (CV = 0.298). Individuals were encountered too infrequently to produce a Iow-variance estimate, and distance sampling thus may be impracticable for monitoring this relatively rare species. I developed a set of multivariate habitat models using binary logistic regression techniques, based on measurement of 22 variables in 56 plots occupied by Swainson's Warblers and 110 unoccupied plots. Occupied areas were characterized by high stem density of cane (Arundinaria gigantea) and other shrub layer vegetation, and presence of abundant and accessible leaf litter. I recommend two habitat models, which correctly classified 87-89% of plots in cross-validation runs, for potential use in habitat assessment at other locations.

Aviation Communications Emulation Testbed

NASA Technical Reports Server (NTRS)

Sheehe, Charles; Mulkerin, Tom

2004-01-01

Aviation related applications that rely upon datalink for information exchange are increasingly being developed and deployed. The increase in the quantity of applications and associated data communications will expose problems and issues to resolve. NASA s Glenn Research Center has prepared to study the communications issues that will arise as datalink applications are employed within the National Airspace System (NAS) by developing an aviation communications emulation testbed. The Testbed is evolving and currently provides the hardware and software needed to study the communications impact of Air Traffic Control (ATC) and surveillance applications in a densely populated environment. The communications load associated with up to 160 aircraft transmitting and receiving ATC and surveillance data can be generated in realtime in a sequence similar to what would occur in the NAS. The ATC applications that can be studied are the Aeronautical Telecommunications Network s (ATN) Context Management (CM) and Controller Pilot Data Link Communications (CPDLC). The Surveillance applications are Automatic Dependent Surveillance - Broadcast (ADS-B) and Traffic Information Services - Broadcast (TIS-B).

Radio-transmitters do not affect seasonal productivity of female Golden-winged Warblers

USGS Publications Warehouse

Streby, Henry M.; Peterson, Sean M.; Gesmundo, Callie; Johnson, Michael K.; Fish, Alexander C.; Lehman, Justin A.; Andersen, David E.

2013-01-01

Investigating the potential effects of handling and marking techniques on study animals is important for correct interpretation of research results and to effect progress in data-collection methods. Few investigators have compared the reproductive output of radio-tagged and non-radio-tagged songbirds, and no one to date has examined the possible effect of radio-tagging adult songbirds on the survival of their fledglings. In 2011 and 2012, we compared several parameters of reproductive output of two groups of female Golden-winged Warblers (Vermivora chrysoptera) breeding in Minnesota, including 45 females with radio-transmitters and 73 females we did not capture, handle, or mark. We found no difference between groups in clutch sizes, hatching success, brood sizes, length of incubation and nestling stages, fledging success, number of fledglings, or survival of fledglings to independence. Thus, radio-tags had no measurable impact on the productivity of female Golden-winged Warblers. Our results build upon previous studies where investigators have reported no effects of radio-tagging on the breeding parameters of songbirds by also demonstrating no effect of radio-tagging through the post-fledging period and, therefore, the entire breeding season.

Population genetic structure and dispersal across a fragmented landscape in cerulean warblers (Dendroica cerulea)

Treesearch

M.L. Veit; R.J. Robertson; P.B. Hamel; V.L. Friesen

2005-01-01

Cerulean warblers (Dendroica cerulea) have experienced significant declines across their breeding range and presently exist in disjunct populations, largely because of extensive loss and fragmentation of their breeding and wintering habitat. Despite this overall decline, a recent north-eastern expansion of the breeding range has been proposed, and...

Internet Tomography in Support of Internet and Network Simulation and Emulation Modelling

NASA Astrophysics Data System (ADS)

Moloisane, A.; Ganchev, I.; O'Droma, M.

Internet performance measurement data extracted through Internet Tomography techniques and metrics and how it may be used to enhance the capacity of network simulation and emulation modelling is addressed in this paper. The advantages of network simulation and emulation as a means to aid design and develop the component networks, which make up the Internet and are fundamental to its ongoing evolution, are highlighted. The Internet's rapid growth has spurred development of new protocols and algorithms to meet changing operational requirements such as security, multicast delivery, mobile networking, policy management, and quality of service (QoS) support. Both the development and evaluation of these operational tools requires the answering of many design and operational questions. Creating the technical support required by network engineers and managers in their efforts to seek answers to these questions is in itself a major challenge. Within the Internet the number and range of services supported continues to grow exponentially, from legacy and client/server applications to VoIP, multimedia streaming services and interactive multimedia services. Services have their own distinctive requirements and idiosyncrasies. They respond differently to bandwidth limitations, latency and jitter problems. They generate different types of “conversations” between end-user terminals, back-end resources and middle-tier servers. To add to the complexity, each new or enhanced service introduced onto the network contends for available bandwidth with every other service. In an effort to ensure networking products and resources being designed and developed handling diverse conditions encountered in real Internet environments, network simulation and emulation modelling is a valuable tool, and becoming a critical element, in networking product and application design and development. The better these laboratory tools reflect real-world environment and conditions the more helpful to

Emulation of Condensed Fuel Flames Using a Burning Rate Emulator (BRE) in Microgravity

NASA Technical Reports Server (NTRS)

Markan, A.; Quintiere, J. G.; Sunderland, P. B.; De Ris, J. L.; Stocker, D. P.

2017-01-01

The Burning Rate Emulator (BRE) is a gaseous fuel burner developed to emulate the burning of condensed phase fuels. The current study details several tests at the NASA Glenn 5-s drop facility to test the BRE technique in microgravity conditions. The tests are conducted for two burner diameters, 25 mm and 50 mm respectively, with methane and ethylene as the fuels. The ambient pressure, oxygen content and fuel flow rate are additional parameters. The microgravity results exhibit a nominally hemispherical flame with decelerating growth and quasi-steady heat flux after about 5 seconds. The BRE burner was evaluated with a transient analysis to assess the extent of steady-state achieved. The burning rate and flame height recorded at the end of the drop are correlated using two steady-state purely diffusive models. A higher burning rate for the bigger burner as compared to theory indicates the significance of gas radiation. The effect of the ambient pressure and oxygen concentration on the heat of gasification are also examined.

Is Management for Golden-winged Warblers and Cerulean Warblers Compatible?

Treesearch

Kenneth V. Rosenberg Paul B. Hamel

2005-01-01

Conservation of species with high Partners in Flight concern scores may suggest management for apparently conflicting habitat needs on a given property or specific site, such as birds requiring early-successional vs. latersuccessional broadleaved forests. Two species of concern with distinctly different habitat needs provide a case study for consideration. Declining...

The Mira-Titan Universe. II. Matter Power Spectrum Emulation

NASA Astrophysics Data System (ADS)

Lawrence, Earl; Heitmann, Katrin; Kwan, Juliana; Upadhye, Amol; Bingham, Derek; Habib, Salman; Higdon, David; Pope, Adrian; Finkel, Hal; Frontiere, Nicholas

2017-09-01

We introduce a new cosmic emulator for the matter power spectrum covering eight cosmological parameters. Targeted at optical surveys, the emulator provides accurate predictions out to a wavenumber k˜ 5 Mpc-1 and redshift z≤slant 2. In addition to covering the standard set of ΛCDM parameters, massive neutrinos and a dynamical dark energy of state are included. The emulator is built on a sample set of 36 cosmological models, carefully chosen to provide accurate predictions over the wide and large parameter space. For each model, we have performed a high-resolution simulation, augmented with 16 medium-resolution simulations and TimeRG perturbation theory results to provide accurate coverage over a wide k-range; the data set generated as part of this project is more than 1.2Pbytes. With the current set of simulated models, we achieve an accuracy of approximately 4%. Because the sampling approach used here has established convergence and error-control properties, follow-up results with more than a hundred cosmological models will soon achieve ˜ 1 % accuracy. We compare our approach with other prediction schemes that are based on halo model ideas and remapping approaches. The new emulator code is publicly available.

The Mira-Titan Universe. II. Matter Power Spectrum Emulation

DOE PAGES

Lawrence, Earl; Heitmann, Katrin; Kwan, Juliana; ...

2017-09-20

We introduce a new cosmic emulator for the matter power spectrum covering eight cosmological parameters. Targeted at optical surveys, the emulator provides accurate predictions out to a wavenumber k ~ 5Mpc -1 and redshift z ≤ 2. Besides covering the standard set of CDM parameters, massive neutrinos and a dynamical dark energy of state are included. The emulator is built on a sample set of 36 cosmological models, carefully chosen to provide accurate predictions over the wide and large parameter space. For each model, we have performed a high-resolution simulation, augmented with sixteen medium-resolution simulations and TimeRG perturbation theory resultsmore » to provide accurate coverage of a wide k-range; the dataset generated as part of this project is more than 1.2Pbyte. With the current set of simulated models, we achieve an accuracy of approximately 4%. Because the sampling approach used here has established convergence and error-control properties, follow-on results with more than a hundred cosmological models will soon achieve ~1% accuracy. We compare our approach with other prediction schemes that are based on halo model ideas and remapping approaches. The new emulator code is publicly available.« less

The Mira-Titan Universe. II. Matter Power Spectrum Emulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence, Earl; Heitmann, Katrin; Kwan, Juliana

We introduce a new cosmic emulator for the matter power spectrum covering eight cosmological parameters. Targeted at optical surveys, the emulator provides accurate predictions out to a wavenumber k ~ 5Mpc -1 and redshift z ≤ 2. Besides covering the standard set of CDM parameters, massive neutrinos and a dynamical dark energy of state are included. The emulator is built on a sample set of 36 cosmological models, carefully chosen to provide accurate predictions over the wide and large parameter space. For each model, we have performed a high-resolution simulation, augmented with sixteen medium-resolution simulations and TimeRG perturbation theory resultsmore » to provide accurate coverage of a wide k-range; the dataset generated as part of this project is more than 1.2Pbyte. With the current set of simulated models, we achieve an accuracy of approximately 4%. Because the sampling approach used here has established convergence and error-control properties, follow-on results with more than a hundred cosmological models will soon achieve ~1% accuracy. We compare our approach with other prediction schemes that are based on halo model ideas and remapping approaches. The new emulator code is publicly available.« less

The Use and Abuses of Emulation as a Pedagogical Practice

ERIC Educational Resources Information Center

Jonas, Mark E.; Chambers, Drew W.

2017-01-01

From the late eighteenth through the end of the nineteenth century, educational philosophers and practitioners debated the benefits and shortcomings of the use of emulation in schools. During this period, "emulation" referred to a pedagogy that leveraged comparisons between students as a tool to motivate them to higher achievement. Many…

Demonstration of emulator-based Bayesian calibration of safety analysis codes: Theory and formulation

DOE PAGES

Yurko, Joseph P.; Buongiorno, Jacopo; Youngblood, Robert

2015-05-28

System codes for simulation of safety performance of nuclear plants may contain parameters whose values are not known very accurately. New information from tests or operating experience is incorporated into safety codes by a process known as calibration, which reduces uncertainty in the output of the code and thereby improves its support for decision-making. The work reported here implements several improvements on classic calibration techniques afforded by modern analysis techniques. The key innovation has come from development of code surrogate model (or code emulator) construction and prediction algorithms. Use of a fast emulator makes the calibration processes used here withmore » Markov Chain Monte Carlo (MCMC) sampling feasible. This study uses Gaussian Process (GP) based emulators, which have been used previously to emulate computer codes in the nuclear field. The present work describes the formulation of an emulator that incorporates GPs into a factor analysis-type or pattern recognition-type model. This “function factorization” Gaussian Process (FFGP) model allows overcoming limitations present in standard GP emulators, thereby improving both accuracy and speed of the emulator-based calibration process. Calibration of a friction-factor example using a Method of Manufactured Solution is performed to illustrate key properties of the FFGP based process.« less

Amount and type of forest cover and edge are important predictorsof golden-cheeked warbler density

Treesearch

Rebecca G. Peak; Frank R. III. Thompson

2013-01-01

Considered endangered by the U.S. Fish and Wildlife Service, the Golden-cheeked Warbler (Setophaga chrysoparia) breeds exclusively in the juniper--oak (Juniperus ashei--Quercus spp.) woodlands of central Texas. Large-scale, spatially explicit models that predict population density as a function of habitat and landscape variables...

Boosting flood warning schemes with fast emulator of detailed hydrodynamic models

NASA Astrophysics Data System (ADS)

Bellos, V.; Carbajal, J. P.; Leitao, J. P.

2017-12-01

Floods are among the most destructive catastrophic events and their frequency has incremented over the last decades. To reduce flood impact and risks, flood warning schemes are installed in flood prone areas. Frequently, these schemes are based on numerical models which quickly provide predictions of water levels and other relevant observables. However, the high complexity of flood wave propagation in the real world and the need of accurate predictions in urban environments or in floodplains hinders the use of detailed simulators. This sets the difficulty, we need fast predictions that meet the accuracy requirements. Most physics based detailed simulators although accurate, will not fulfill the speed demand. Even if High Performance Computing techniques are used (the magnitude of required simulation time is minutes/hours). As a consequence, most flood warning schemes are based in coarse ad-hoc approximations that cannot take advantage a detailed hydrodynamic simulation. In this work, we present a methodology for developing a flood warning scheme using an Gaussian Processes based emulator of a detailed hydrodynamic model. The methodology consists of two main stages: 1) offline stage to build the emulator; 2) online stage using the emulator to predict and generate warnings. The offline stage consists of the following steps: a) definition of the critical sites of the area under study, and the specification of the observables to predict at those sites, e.g. water depth, flow velocity, etc.; b) generation of a detailed simulation dataset to train the emulator; c) calibration of the required parameters (if measurements are available). The online stage is carried on using the emulator to predict the relevant observables quickly, and the detailed simulator is used in parallel to verify key predictions of the emulator. The speed gain given by the emulator allows also to quantify uncertainty in predictions using ensemble methods. The above methodology is applied in real

Population decline of the Elfin-woods Warbler Setophaga angelae in eastern Puerto Rico

Treesearch

W.J. Arendt; S.S. Qian; K. Mineard

2013-01-01

We estimated the population density of the globally threatened Elfin-woods Warbler Setophaga angelae within two forest types at different elevations in the Luquillo Experimental Forest in north-eastern Puerto Rico. Population densities ranged from 0.01 to 0.02 individuals/ha in elfin woodland and 0.06–0.26 individuals/ha in palo colorado forest in 2006, with average...

Mixed-mode oscillations in memristor emulator based Liénard system

NASA Astrophysics Data System (ADS)

Kingston, S. Leo; Suresh, K.; Thamilmaran, K.

2018-04-01

We report the existence of mixed-mode oscillations in memristor emulator based Liénard system which is externally driven by sinusoidal force. The charge and flux relationship of memristor emulator device explored based on the smooth cubic nonlinear element. The system exhibits the successive period adding sequences of mixed-mode oscillations in the wide parameter region. The electronics circuit of the memristor emulator is successfully implemented through PSpice simulation and mixed mode oscillations are observed through PSpice experiment and the obtained results are qualitatively matches with the numerical simulation.

Coping with shifting nest predation refuges by European reed Warblers Acrocephalus scirpaceus.

PubMed

Halupka, Lucyna; Halupka, Konrad; Klimczuk, Ewelina; Sztwiertnia, Hanna

2014-01-01

Predation, the most important source of nest mortality in altricial birds, has been a subject of numerous studies during past decades. However, the temporal dynamics between changing predation pressures and parental responses remain poorly understood. We analysed characteristics of 524 nests of European reed warblers monitored during six consecutive breeding seasons in the same area, and found some support for the shifting nest predation refuge hypothesis. Nest site characteristics were correlated with nest fate, but a nest with the same nest-site attributes could be relatively safe in one season and vulnerable to predation in another. Thus nest predation refuges were ephemeral and there was no between-season consistency in nest predation patterns. Reed warblers that lost their first nests in a given season did not disperse farther for the subsequent reproductive attempt, compared to successful individuals, but they introduced more changes to their second nest sites. In subsequent nests, predation risk remained constant for birds that changed nest-site characteristics, but increased for those that did not. At the between-season temporal scale, individual birds did not perform better with age in terms of reducing nest predation risk. We conclude that the experience acquired in previous years may not be useful, given that nest predation refuges are not stable.

Coping with Shifting Nest Predation Refuges by European Reed Warblers Acrocephalus scirpaceus

PubMed Central

Halupka, Lucyna; Halupka, Konrad; Klimczuk, Ewelina; Sztwiertnia, Hanna

2014-01-01

Predation, the most important source of nest mortality in altricial birds, has been a subject of numerous studies during past decades. However, the temporal dynamics between changing predation pressures and parental responses remain poorly understood. We analysed characteristics of 524 nests of European reed warblers monitored during six consecutive breeding seasons in the same area, and found some support for the shifting nest predation refuge hypothesis. Nest site characteristics were correlated with nest fate, but a nest with the same nest-site attributes could be relatively safe in one season and vulnerable to predation in another. Thus nest predation refuges were ephemeral and there was no between-season consistency in nest predation patterns. Reed warblers that lost their first nests in a given season did not disperse farther for the subsequent reproductive attempt, compared to successful individuals, but they introduced more changes to their second nest sites. In subsequent nests, predation risk remained constant for birds that changed nest-site characteristics, but increased for those that did not. At the between-season temporal scale, individual birds did not perform better with age in terms of reducing nest predation risk. We conclude that the experience acquired in previous years may not be useful, given that nest predation refuges are not stable. PMID:25522327

The structure of western warbler assemblages: Analysis of foraging behavior and habitat selection in Oregon

USGS Publications Warehouse

Morrison, Michael L.

1981-01-01

This study examines the foraging behavior and habitat selection of a MacGillivray's (Oporornis tolmiei)-Orange-crowned (Vermivora celata)-Wilson's (Wilsonia pusilla) warbler assemblage that occurred on early-growth clearcuts in western Oregon during breeding. Sites were divided into two groups based on the presence or absence of deciduous trees. Density estimates for each species were nearly identical between site classes except for Wilson's, whose density declined on nondeciduous tree sites. Analysis of vegetation parameters within the territories of the species identified deciduous tree cover as the variable of primary importance in the separation of warblers on each site, so that the assemblage could be arranged on a continuum of increasing deciduous tree cover. MacGillivray's and Wilson's extensively used shrub cover and deciduous tree cover, respectively; Orange-crowns were associated with both vegetation types. When the deciduous tree cover was reduced, Orange-crowns concentrated foraging activities in shrub cover and maintained nondisturbance densities. Indices of foraging-height diversity showed a marked decrease after the removal of deciduous trees. All species except MacGillivray's foraged lower in the vegatative substrate on the nondeciduous tree sites; MacGillivray's concentrated foraging activities in the low shrub cover on both sites. Indices of foraging overlap revealed a general pattern of decreased segregation by habitat after removal of deciduous trees. I suggest that the basic patterns of foraging behavior and habitat selection evidenced today in western North America were initially developed by ancestral warblers before their invasion of the west. Species successfully colonizing western habitats were probably preadapted to the conditions they encountered, with new habitats occupied without obvious evolutionary modifications.

8755 Emulator Design

DTIC Science & Technology

1988-12-01

Break Control....................51 8755 I/O Control..................54 Z-100 Control Software................. 55 Pass User Memory...the emulator SRAM and the other is 55 for the target SRAM. If either signal is replaced by the NACK signal the host computer displays an error message...Block Diagram 69 AUU M/M 8 in Fiur[:. cemti Daga 70m F’M I-- ’I ANLAD AMam U52 COMM ow U2 i M.2 " -n ax- U 6_- Figure 2b. Schematic Diagram 71 )-M -A -I

A polymorphic reconfigurable emulator for parallel simulation

NASA Technical Reports Server (NTRS)

Parrish, E. A., Jr.; Mcvey, E. S.; Cook, G.

1980-01-01

Microprocessor and arithmetic support chip technology was applied to the design of a reconfigurable emulator for real time flight simulation. The system developed consists of master control system to perform all man machine interactions and to configure the hardware to emulate a given aircraft, and numerous slave compute modules (SCM) which comprise the parallel computational units. It is shown that all parts of the state equations can be worked on simultaneously but that the algebraic equations cannot (unless they are slowly varying). Attempts to obtain algorithms that will allow parellel updates are reported. The word length and step size to be used in the SCM's is determined and the architecture of the hardware and software is described.

Emulation of simulations of atmospheric dispersion at Fukushima for Sobol' sensitivity analysis

NASA Astrophysics Data System (ADS)

Girard, Sylvain; Korsakissok, Irène; Mallet, Vivien

2015-04-01

Polyphemus/Polair3D, from which derives IRSN's operational model ldX, was used to simulate the atmospheric dispersion at the Japan scale of radionuclides after the Fukushima disaster. A previous study with the screening method of Morris had shown that - The sensitivities depend a lot on the considered output; - Only a few of the inputs are non-influential on all considered outputs; - Most influential inputs have either non-linear effects or are interacting. These preliminary results called for a more detailed sensitivity analysis, especially regarding the characterization of interactions. The method of Sobol' allows for a precise evaluation of interactions but requires large simulation samples. Gaussian process emulators for each considered outputs were built in order to relieve this computational burden. Globally aggregated outputs proved to be easy to emulate with high accuracy, and associated Sobol' indices are in broad agreement with previous results obtained with the Morris method. More localized outputs, such as temporal averages of gamma dose rates at measurement stations, resulted in lesser emulator performances: tests simulations could not satisfactorily be reproduced by some emulators. These outputs are of special interest because they can be compared to available observations, for instance for calibration purpose. A thorough inspection of prediction residuals hinted that the model response to wind perturbations often behaved in very distinct regimes relatively to some thresholds. Complementing the initial sample with wind perturbations set to the extreme values allowed for sensible improvement of some of the emulators while other remained too unreliable to be used in a sensitivity analysis. Adaptive sampling or regime-wise emulation could be tried to circumvent this issue. Sobol' indices for local outputs revealed interesting patterns, mostly dominated by the winds, with very high interactions. The emulators will be useful for subsequent studies. Indeed

Seasonal productivity and nest survival of Golden-cheeked Warblers vary with forest type and edge density

Treesearch

Rebecca G. Peak; Frank R., III Thompson

2014-01-01

Knowledge of the demography and habitat requirements of the endangered Golden-cheeked Warbler (Setophaga chrysoparia) is needed for its recovery, including measures of productivity instead of reproductive indices. We report on breeding phenology and demography, calculate model-based estimates of nest survival and seasonal productivity and evaluate...

The Ghost Condition: Imitation Versus Emulation in Young Children's Observational Learning.

ERIC Educational Resources Information Center

Thompson, Doreen E.; Russell, James

2004-01-01

Although observational learning by children may occur through imitating a modeler's actions, it can also occur through learning about an object's dynamic affordances- a process that M. Tomasello (1996) calls "emulation." The relative contributions of imitation and emulation within observational learning were examined in a study with 14- to…

Phylogeography of a Habitat Specialist with High Dispersal Capability: The Savi’s Warbler Locustella luscinioides

PubMed Central

Neto, Júlio M.; Arroyo, José L.; Bargain, Bruno; Monrós, Juan S.; Mátrai, Norbert; Procházka, Petr; Zehtindjiev, Pavel

2012-01-01

In order to describe the influence of Pleistocene glaciations on the genetic structure and demography of a highly mobile, but specialized, passerine, the Savi’s Warbler (Locustella luscinioides), mitochondrial DNA sequences (ND2) and microsatellites were analysed in c.330 individuals of 17 breeding and two wintering populations. Phylogenetic, population genetics and coalescent methods were used to describe the genetic structure, determine the timing of the major splits and model the demography of populations. Savi’s Warblers split from its sister species c.8 million years ago and have two major haplotype groups that diverged in the early/middle Pleistocene. One of these clades originated in the Balkans and is currently widespread, showing strong evidence for population expansion; whereas the other is restricted to Iberia and remained stable. Microsatellites agreed with a genetic break around the Pyrenees, but showed considerable introgression and a weaker genetic structure. Both genetic markers showed an isolation-by-distance pattern associated with the population expansion of the eastern clade. Breeding populations seem to be segregated at the wintering sites, but results on migratory connectivity are preliminary. Savi’s Warbler is the only known migratory bird species in which Iberian birds did not expand beyond the Pyrenees after the last glaciation. Despite the long period of independent evolution of western and eastern populations, complete introgression occurred when these groups met in Iberia. Mitochondrial sequences indicated the existence of refugia-within-refugia in the Iberian Peninsula during the last glacial period, which is surprising given the high dispersal capacity of this species. Plumage differences of eastern subspecies seemed to have evolved recently through natural selection, in agreement with the glacial expansion hypothesis. This study supports the great importance of the Iberian Peninsula and its role for the conservation of genetic

Behavioral activities of male Cerulean Warblers in relation to habitat characteristics

USGS Publications Warehouse

Wood, Petra Bohall; Perkins, Kelly A.

2012-01-01

Activities of 29 male Cerulean Warblers (Setophaga cerulea) were quantified on two sites in West Virginia during May–June 2005. Singing and foraging were the most common of 11 observed behavioral activities (81.6%), while maintenance and mating behaviors were uncommonly observed. Male activity differed among vegetative strata (P  =  0.02) with lower- and mid-canopy strata used most often (70% of observations), especially for foraging, perching, and preening. The upper-canopy was used primarily for singing, particularly within core areas of territories and in association with canopy gaps. Foraging occurred more than expected outside of core areas. Males were associated with canopy gaps during 30% of observations, but the distribution of behavioral activities was not significantly related (P  =  0.06) to gap presence. Males used 23 different tree species for a variety of activities with oaks (Quercus spp.) used most often on the xeric site and black cherry (Prunus serotina) and black locust (Robinia pseudoacacia) on the mesic site. Tree species used for singing differed between core and non-core areas (P < 0.0001) but distribution of singing and foraging activity did not differ among tree species (P  =  0.13). Cerulean Warblers appear to be flexible in use of tree species. Their use of different canopy strata for different behavioral activities provides an explanation for the affinity this species exhibits for a vertically stratified forest canopy.

Fast emulation of track reconstruction in the CMS simulation

NASA Astrophysics Data System (ADS)

Komm, Matthias; CMS Collaboration

2017-10-01

Simulated samples of various physics processes are a key ingredient within analyses to unlock the physics behind LHC collision data. Samples with more and more statistics are required to keep up with the increasing amounts of recorded data. During sample generation, significant computing time is spent on the reconstruction of charged particle tracks from energy deposits which additionally scales with the pileup conditions. In CMS, the FastSimulation package is developed for providing a fast alternative to the standard simulation and reconstruction workflow. It employs various techniques to emulate track reconstruction effects in particle collision events. Several analysis groups in CMS are utilizing the package, in particular those requiring many samples to scan the parameter space of physics models (e.g. SUSY) or for the purpose of estimating systematic uncertainties. The strategies for and recent developments in this emulation are presented, including a novel, flexible implementation of tracking emulation while retaining a sufficient, tuneable accuracy.

A Device to Emulate Diffusion and Thermal Conductivity Using Water Flow

ERIC Educational Resources Information Center

Blanck, Harvey F.

2005-01-01

A device designed to emulate diffusion and thermal conductivity using flowing water is reviewed. Water flowing through a series of cells connected by a small tube in each partition in this plastic model is capable of emulating diffusion and thermal conductivity that occurs in variety of systems described by several mathematical equations.

Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest.

DOE Office of Scientific and Technical Information (OSTI.GOV)

John Kilgo

2005-04-20

The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging near gaps would find more prey per unit time than those foraging in the surrounding forest. In fact, arthropod abundance was greater >100 m from a gap edge than at 0-30 m or 30-100 m from an edge, due to their abundance on switchcane (Arundinaria gigantea); arthropods did notmore » differ in abundance among distances from gaps on oaks (Quercus spp.) or red maple (Acer rubrum). Similarly, Hooded Warbler foraging attack rates were not higher near gap edges: when foraging for fledglings, attack rate did not differ among distances from gaps, but when foraging for themselves, attack rates actually were lower 0-30 m from gap edges than 30-100 m or >100 m from a gap edge. Foraging attack rate was positively associated with arthropod abundance. Hooded Warblers apparently encountered fewer prey and presumably foraged less efficiently where arthropods were least abundant, i.e., near gaps. That attack rates among birds foraging for fledglings were not affected by distance from gap (and hence arthropod abundance) suggests that prey availability may not be limiting at any location across the forest, despite the depressing effects of gaps on arthropod abundance.« less

Yielding physically-interpretable emulators - A Sparse PCA approach

NASA Astrophysics Data System (ADS)

Galelli, S.; Alsahaf, A.; Giuliani, M.; Castelletti, A.

2015-12-01

Projection-based techniques, such as Principal Orthogonal Decomposition (POD), are a common approach to surrogate high-fidelity process-based models by lower order dynamic emulators. With POD, the dimensionality reduction is achieved by using observations, or 'snapshots' - generated with the high-fidelity model -, to project the entire set of input and state variables of this model onto a smaller set of basis functions that account for most of the variability in the data. While reduction efficiency and variance control of POD techniques are usually very high, the resulting emulators are structurally highly complex and can hardly be given a physically meaningful interpretation as each basis is a projection of the entire set of inputs and states. In this work, we propose a novel approach based on Sparse Principal Component Analysis (SPCA) that combines the several assets of POD methods with the potential for ex-post interpretation of the emulator structure. SPCA reduces the number of non-zero coefficients in the basis functions by identifying a sparse matrix of coefficients. While the resulting set of basis functions may retain less variance of the snapshots, the presence of a few non-zero coefficients assists in the interpretation of the underlying physical processes. The SPCA approach is tested on the reduction of a 1D hydro-ecological model (DYRESM-CAEDYM) used to describe the main ecological and hydrodynamic processes in Tono Dam, Japan. An experimental comparison against a standard POD approach shows that SPCA achieves the same accuracy in emulating a given output variable - for the same level of dimensionality reduction - while yielding better insights of the main process dynamics.

Arthropods of native and exotic vegetation and their association with willow flycatchers and Wilson's warblers

Treesearch

Linda S. DeLay; Deborah M. Finch; Sandra Brantley; Richard Fagerlund; Michael D. Means; Jeffrey F. Kelly

1999-01-01

We compared abundance of migrating Willow Flycatchers and Wilson's Warblers to the abundance of arthropods in exotic and native vegetation at Bosque del Apache National Wildlife Refuge. We trapped arthropods using glue-boards in 1996 and 1997 in the same cottonwood, saltcedar, and willow habitats where we mist-netted birds during spring and fall migration. There...

High-emulation mask recognition with high-resolution hyperspectral video capture system

NASA Astrophysics Data System (ADS)

Feng, Jiao; Fang, Xiaojing; Li, Shoufeng; Wang, Yongjin

2014-11-01

We present a method for distinguishing human face from high-emulation mask, which is increasingly used by criminals for activities such as stealing card numbers and passwords on ATM. Traditional facial recognition technique is difficult to detect such camouflaged criminals. In this paper, we use the high-resolution hyperspectral video capture system to detect high-emulation mask. A RGB camera is used for traditional facial recognition. A prism and a gray scale camera are used to capture spectral information of the observed face. Experiments show that mask made of silica gel has different spectral reflectance compared with the human skin. As multispectral image offers additional spectral information about physical characteristics, high-emulation mask can be easily recognized.

Internal monitoring of GBTx emulator using IPbus for CBM experiment

NASA Astrophysics Data System (ADS)

Mandal, Swagata; Zabolotny, Wojciech; Sau, Suman; Chkrabarti, Amlan; Saini, Jogender; Chattopadhyay, Subhasis; Pal, Sushanta Kumar

2015-09-01

The Compressed Baryonic Matter (CBM) experiment is a part of the Facility for Antiproton and Ion Research (FAIR) in Darmstadt at GSI. In CBM experiment a precisely time synchronized fault tolerant self-triggered electronics is required for Data Acquisition (DAQ) system in CBM experiments which can support high data rate (up to several TB/s). As a part of the implementation of the DAQ system of Muon Chamber (MUCH) which is one of the important detectors in CBM experiment, a FPGA based Gigabit Transceiver (GBTx) emulator is implemented. Readout chain for MUCH consists of XYTER chips (Front end electronics) which will be directly connected to detector, GBTx emulator, Data Processing Board (DPB) and First level event selector board (FLIB) with backend software interface. GBTx emulator will be connected with the XYTER emulator through LVDS (Low Voltage Differential Signalling) line in the front end and in the back end it is connected with DPB through 4.8 Gbps optical link. IPBus over Ethernet is used for internal monitoring of the registers within the GBTx. In IPbus implementation User Datagram Protocol (UDP) stack is used in transport layer of OSI model so that GBTx can be controlled remotely. A Python script is used at computer side to drive IPbus controller.

Emulation-Based Virtual Laboratories: A Low-Cost Alternative to Physical Experiments in Control Engineering Education

ERIC Educational Resources Information Center

Goodwin, G. C.; Medioli, A. M.; Sher, W.; Vlacic, L. B.; Welsh, J. S.

2011-01-01

This paper argues the case for emulation-based virtual laboratories in control engineering education. It demonstrates that such emulation experiments can give students an industrially relevant educational experience at relatively low cost. The paper also describes a particular emulation-based system that has been developed with the aim of giving…

Advancing our understanding of the non-breeding distribution of Cerulean Warbler (Setophaga cerulea) in the Andes

Treesearch

Gabriel J. Colorado; Paul B. Hamel; Amanda D. Rodewald; David Mehlman

2012-01-01

Recent population declines have prompted the International Union for the Conservation of Nature to list Cerulean Warbler (Setophaga cerulea: Parulidae) as a Vulnerable species. It is believed that this decline may be related to habitat loss through its entire range, mainly due to deforestation and degradation of its habitats. In response, members of...

Patterns of gene flow and selection across multiple species of Acrocephalus warblers: footprints of parallel selection on the Z chromosome.

PubMed

Reifová, Radka; Majerová, Veronika; Reif, Jiří; Ahola, Markus; Lindholm, Antero; Procházka, Petr

2016-06-16

Understanding the mechanisms and selective forces leading to adaptive radiations and origin of biodiversity is a major goal of evolutionary biology. Acrocephalus warblers are small passerines that underwent an adaptive radiation in the last approximately 10 million years that gave rise to 37 extant species, many of which still hybridize in nature. Acrocephalus warblers have served as model organisms for a wide variety of ecological and behavioral studies, yet our knowledge of mechanisms and selective forces driving their radiation is limited. Here we studied patterns of interspecific gene flow and selection across three European Acrocephalus warblers to get a first insight into mechanisms of radiation of this avian group. We analyzed nucleotide variation at eight nuclear loci in three hybridizing Acrocephalus species with overlapping breeding ranges in Europe. Using an isolation-with-migration model for multiple populations, we found evidence for unidirectional gene flow from A. scirpaceus to A. palustris and from A. palustris to A. dumetorum. Gene flow was higher between genetically more closely related A. scirpaceus and A. palustris than between ecologically more similar A. palustris and A. dumetorum, suggesting that gradual accumulation of intrinsic barriers rather than divergent ecological selection are more efficient in restricting interspecific gene flow in Acrocephalus warblers. Although levels of genetic differentiation between different species pairs were in general not correlated, we found signatures of apparently independent instances of positive selection at the same two Z-linked loci in multiple species. Our study brings the first evidence that gene flow occurred during Acrocephalus radiation and not only between sister species. Interspecific gene flow could thus be an important source of genetic variation in individual Acrocephalus species and could have accelerated adaptive evolution and speciation rate in this avian group by creating novel genetic

Migration and the evolution of sexual dichromatism: evolutionary loss of female coloration with migration among wood-warblers

PubMed Central

Simpson, Richard K.; Johnson, Michele A.; Murphy, Troy G.

2015-01-01

The mechanisms underlying evolutionary changes in sexual dimorphism have long been of interest to biologists. A striking gradient in sexual dichromatism exists among songbirds in North America, including the wood-warblers (Parulidae): males are generally more colourful than females at northern latitudes, while the sexes are similarly ornamented at lower latitudes. We use phylogenetically controlled comparative analysis to test three non-mutually exclusive hypotheses for the evolution of sexual dichromatism among wood-warblers. The first two hypotheses focus on the loss of female coloration with the evolution of migration, either owing to the costs imposed by visual predators during migration, or owing to the relaxation of selection for female social signalling at higher latitudes. The third hypothesis focuses on whether sexual dichromatism evolved owing to changes in male ornamentation as the strength of sexual selection increases with breeding latitude. To test these hypotheses, we compared sexual dichromatism to three variables: the presence of migration, migration distance, and breeding latitude. We found that the presence of migration and migration distance were both positively correlated with sexual dichromatism, but models including breeding latitude alone were not strongly supported. Ancestral state reconstruction supports the hypothesis that the ancestral wood-warblers were monochromatic, with both colourful males and females. Combined, these results are consistent with the hypotheses that the evolution of migration is associated with the relaxation of selection for social signalling among females and that there are increased predatory costs along longer migratory routes for colourful females. These results suggest that loss of female ornamentation can be a driver of sexual dichromatism and that social or natural selection may be a stronger contributor to variation in dichromatism than sexual selection. PMID:26019159

Statistical emulation of landslide-induced tsunamis at the Rockall Bank, NE Atlantic

PubMed Central

Guillas, S.; Georgiopoulou, A.; Dias, F.

2017-01-01

Statistical methods constitute a useful approach to understand and quantify the uncertainty that governs complex tsunami mechanisms. Numerical experiments may often have a high computational cost. This forms a limiting factor for performing uncertainty and sensitivity analyses, where numerous simulations are required. Statistical emulators, as surrogates of these simulators, can provide predictions of the physical process in a much faster and computationally inexpensive way. They can form a prominent solution to explore thousands of scenarios that would be otherwise numerically expensive and difficult to achieve. In this work, we build a statistical emulator of the deterministic codes used to simulate submarine sliding and tsunami generation at the Rockall Bank, NE Atlantic Ocean, in two stages. First we calibrate, against observations of the landslide deposits, the parameters used in the landslide simulations. This calibration is performed under a Bayesian framework using Gaussian Process (GP) emulators to approximate the landslide model, and the discrepancy function between model and observations. Distributions of the calibrated input parameters are obtained as a result of the calibration. In a second step, a GP emulator is built to mimic the coupled landslide-tsunami numerical process. The emulator propagates the uncertainties in the distributions of the calibrated input parameters inferred from the first step to the outputs. As a result, a quantification of the uncertainty of the maximum free surface elevation at specified locations is obtained. PMID:28484339

Statistical emulation of landslide-induced tsunamis at the Rockall Bank, NE Atlantic.

PubMed

Salmanidou, D M; Guillas, S; Georgiopoulou, A; Dias, F

2017-04-01

Statistical methods constitute a useful approach to understand and quantify the uncertainty that governs complex tsunami mechanisms. Numerical experiments may often have a high computational cost. This forms a limiting factor for performing uncertainty and sensitivity analyses, where numerous simulations are required. Statistical emulators, as surrogates of these simulators, can provide predictions of the physical process in a much faster and computationally inexpensive way. They can form a prominent solution to explore thousands of scenarios that would be otherwise numerically expensive and difficult to achieve. In this work, we build a statistical emulator of the deterministic codes used to simulate submarine sliding and tsunami generation at the Rockall Bank, NE Atlantic Ocean, in two stages. First we calibrate, against observations of the landslide deposits, the parameters used in the landslide simulations. This calibration is performed under a Bayesian framework using Gaussian Process (GP) emulators to approximate the landslide model, and the discrepancy function between model and observations. Distributions of the calibrated input parameters are obtained as a result of the calibration. In a second step, a GP emulator is built to mimic the coupled landslide-tsunami numerical process. The emulator propagates the uncertainties in the distributions of the calibrated input parameters inferred from the first step to the outputs. As a result, a quantification of the uncertainty of the maximum free surface elevation at specified locations is obtained.

Nesting ecology of Townsend's warblers in relation to habitat characteristics in a mature boreal forest

USGS Publications Warehouse

Matsuoka, S.M.; Handel, Colleen M.; Roby, D.D.

1997-01-01

We investigated the nesting ecology of Townsend's Warblers (Dendroica townsendi) from 1993-1995 in an unfragmented boreal forest along the lower slopes of the Chugach Mountains in southcentral Alaska. We examined habitat characteristics of nest sites in relation to factors influencing reproductive success. Almost all territory-holding males (98%, n = 40) were successful in acquiring mates. Nest success was 54% (n = 24 nests), with nest survivorship greater during incubation (87%) than during the nestling period (62%). Most nesting failure (80%) was attributable to predation, which occurred primarily during the nestling period. Fifty-five percent of nests containing nestling were infested with the larvae of bird blow-flies (Protocalliphora braueri and P. spenceri), obligatory blood-feeding parasites. The combined effects of Protocalliphora infestation and inclement weather apparently resulted in nestling mortality in 4 of the 24 nests. Nests that escaped predation were placed in white spruce with larger diameter than those lost to predation: nests that escaped blow-fly parasitism were located higher in nest trees and in areas with lower densities of woody shrubs than those that were infested. The availability of potential nest sites with these key features may be important in determining reproductive success in Townsend's Warblers.

Mercury contamination, a potential threat to the globally endangered aquatic warbler Acrocephalus paludicola.

PubMed

Pacyna, Aneta Dorota; Martínez, Carlos Zumalacárregui; Miguélez, David; Jiguet, Frédéric; Polkowska, Żaneta; Wojczulanis-Jakubas, Katarzyna

2017-12-01

Mercury (Hg) contamination is considered a global concern for humans and wildlife, and although the number of studies dealing with that issue continues to increase, some taxonomic groups such as small passerine birds are largely understudied. In this paper, concentration of mercury in the aquatic warbler (Acrocephalus paludicola) feathers, a globally threatened passerine species, was examined. The concentration differences between two ages and sexes were investigated. The comparison of feathers taken on autumn migrants of two age categories act as a comparison of the species' exposure within the two different areas (European breeding or African wintering grounds). The average Hg concentration for all sampled individuals [2.32 μg/g dw (range 0.38-12.76)] is relatively high, compared with values found in other passerine species. An age difference was found, with first-year individuals displaying higher mercury concentrations than adults. This indicates that birds are exposed to mercury pollution during the breeding season, i.e., in the continental floodplains of eastern Europe. The average Hg concentration in feathers grown on the breeding grounds was 3.88 ± 2.59 μg/g dw, closer to the critical value of 5 μg/g dw, which is considered to impair the health of individuals. The findings suggest that mercury pollution may constitute a threat so far neglected for the endangered aquatic warbler.

Social pairing of Seychelles warblers under reduced constraints: MHC, neutral heterozygosity, and age.

PubMed

Wright, David J; Brouwer, Lyanne; Mannarelli, Maria-Elena; Burke, Terry; Komdeur, Jan; Richardson, David S

2016-01-01

The prevalence and significance of precopulatory mate choice remains keenly debated. The major histocompatibility complex (MHC) plays a key role in vertebrate adaptive immunity, and variation at the MHC influences individual survival. Although MHC-dependent mate choice has been documented in certain species, many other studies find no such pattern. This may be, at least in part, because in natural systems constraints may reduce the choices available to individuals and prevent full expression of underlying preferences. We used translocations to previously unoccupied islands to experimentally reduce constraints on female social mate choice in the Seychelles warbler ( Acrocephalus sechellensis ), a species in which patterns of MHC-dependent extrapair paternity (EPP), but not social mate choice, have been observed. We find no evidence of MHC-dependent social mate choice in the new populations. Instead, we find that older males and males with more microsatellite heterozygosity are more likely to have successfully paired. Our data cannot resolve whether these patterns in pairing were due to male-male competition or female choice. However, our research does suggest that female Seychelles warblers do not choose social mates using MHC class I to increase fitness. It may also indicate that the MHC-dependent EPP observed in the source population is probably due to mechanisms other than female precopulatory mate choice based on MHC cues.

Social pairing of Seychelles warblers under reduced constraints: MHC, neutral heterozygosity, and age

PubMed Central

Wright, David J.; Brouwer, Lyanne; Mannarelli, Maria-Elena; Burke, Terry; Komdeur, Jan

2016-01-01

The prevalence and significance of precopulatory mate choice remains keenly debated. The major histocompatibility complex (MHC) plays a key role in vertebrate adaptive immunity, and variation at the MHC influences individual survival. Although MHC-dependent mate choice has been documented in certain species, many other studies find no such pattern. This may be, at least in part, because in natural systems constraints may reduce the choices available to individuals and prevent full expression of underlying preferences. We used translocations to previously unoccupied islands to experimentally reduce constraints on female social mate choice in the Seychelles warbler (Acrocephalus sechellensis), a species in which patterns of MHC-dependent extrapair paternity (EPP), but not social mate choice, have been observed. We find no evidence of MHC-dependent social mate choice in the new populations. Instead, we find that older males and males with more microsatellite heterozygosity are more likely to have successfully paired. Our data cannot resolve whether these patterns in pairing were due to male–male competition or female choice. However, our research does suggest that female Seychelles warblers do not choose social mates using MHC class I to increase fitness. It may also indicate that the MHC-dependent EPP observed in the source population is probably due to mechanisms other than female precopulatory mate choice based on MHC cues. PMID:26792973

Performance Evaluation, Emulation, and Control of Cross-Flow Hydrokinetic Turbines

NASA Astrophysics Data System (ADS)

Cavagnaro, Robert J.

power, and electrical power output of a complete power take-off (PTO) system are utilized to determine the rotor hydrodynamic efficiency (maximum of 17%) and total system efficiency (maximum of 9%). A lab-based dynamometry method yields individual component and total PTO efficiencies, shown to have high variability and strong influence on total system efficiency. Dynamic efficiencies of PTO components can effect the overall efficiency of a turbine system, a result from field characterization. Thus, the ability to evaluate such components and their potential effects on turbine performance prior to field deployment is desirable. Before attempting control experiments with actual turbines, hardware-in-the-loop testing on controllable motor-generator sets or electromechanical emulation machines (EEMs) are explored to better understand power take-off response. The emulator control dynamic equations are presented, methods for scaling turbine parameters are developed and evaluated, and experimental results are presented from three EEMs programmed to emulate the same cross-flow turbine. Although hardware platforms and control implementations varied, results show that each EEM is successful in emulating the turbine model at different power levels, thus demonstrating the general feasibility of the approach. However, performance of motor control under torque command, current command, or speed command differed; torque methods required accurate characterization of the motors while speed methods utilized encoder feedback and more accurately tracked turbine dynamics. In a demonstration of an EEM for evaluating a hydrokinetic turbine implementation, a controller is used to track the maximum power-point of the turbine in response to turbulence. Utilizing realistic inflow conditions and control laws, the emulator dynamic speed response is shown to agree well at low frequencies with simulation but to deviate at high frequencies. The efficacy of an electromechanical emulator as an accurate

Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest

Treesearch

John C. Kilgo

2005-01-01

The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging...

The Mira-Titan Universe. II. Matter Power Spectrum Emulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence, Earl; Heitmann, Katrin; Kwan, Juliana

We introduce a new cosmic emulator for the matter power spectrum covering eight cosmological parameters. Targeted at optical surveys, the emulator provides accurate predictions out to a wavenumber k similar to 5 Mpc(-1) and redshift z <= 2. In addition to covering the standard set of Lambda CDM parameters, massive neutrinos and a dynamical dark energy of state are included. The emulator is built on a sample set of 36 cosmological models, carefully chosen to provide accurate predictions over the wide and large parameter space. For each model, we have performed a high-resolution simulation, augmented with 16 medium-resolution simulations andmore » TimeRG perturbation theory results to provide accurate coverage over a wide k-range; the data set generated as part of this project is more than 1.2Pbytes. With the current set of simulated models, we achieve an accuracy of approximately 4%. Because the sampling approach used here has established convergence and error-control properties, follow-up results with more than a hundred cosmological models will soon achieve similar to 1% accuracy. We compare our approach with other prediction schemes that are based on halo model ideas and remapping approaches.« less

Seasonal and flight-related variation of galectin expression in heart, liver and flight muscles of yellow-rumped warblers (Setophaga coronata).

PubMed

Bradley, Stefanie S; Dick, Morag F; Guglielmo, Christopher G; Timoshenko, Alexander V

2017-10-01

Galectins, a family of multifunctional glycan-binding proteins, are proposed as biomarkers of cellular stress responses. Avian migration is an energetically challenging physical stress, which represents a physiological model of muscular endurance exercises. This study assesses change in galectin gene expression profiles associated with seasonal variation in migratory state and endurance flight in yellow-rumped warblers (Setophaga coronata). Bioinformatics analysis and real-time qPCR were used to analyse the expression of galectins in flight muscle, heart and liver tissues of 15 warblers separated into three groups of winter unflown, and fall migratory flown/unflown birds. Five transcripts similar to chicken and human galectins -1, -2, -3, -4, and -8 were identified in warbler tissues. The expression of these galectins showed no seasonal changes between two experimental groups of birds maintained under unflown winter and fall conditions indicating a minor role of galectins in preparation for migration. However, endurance flight led to a significant elevation of galectin-1 and galectin-3 mRNAs in flight muscles and galectin-3 mRNA in heart tissue while no changes were observed in liver. Different changes were observed for the level of O-GlcNAcylated proteins, which were elevated in flight muscles under winter conditions. These results suggest that secreted galectin-1 and galectin-3 may be active in repair of bird muscles during and following migratory flight and serve as molecular biomarkers of recent arrival from migratory flights in field studies.

Evolutionary dynamics of Rh2 opsins in birds demonstrate an episode of accelerated evolution in the New World warblers (Setophaga)

PubMed Central

Price, Trevor D.

2015-01-01

Low rates of sequence evolution associated with purifying selection can be interrupted by episodic changes in selective regimes. Visual pigments are a unique system in which we can investigate the functional consequences of genetic changes, therefore connecting genotype to phenotype in the context of natural and sexual selection pressures. We study the RH2 and RH1 visual pigments (opsins) across 22 bird species belonging to two ecologically convergent clades, the New World warblers (Parulidae) and Old World warblers (Phylloscopidae), and evaluate rates of evolution in these clades along with data from 21 additional species. We demonstrate generally slow evolution of these opsins: both Rh1 and Rh2 are highly conserved across Old World and New World warblers. However, Rh2 underwent a burst of evolution within the New World genus Setophaga, where it accumulated substitutions at 6 amino acid sites across the species we studied. Evolutionary analyses revealed a significant increase in dN/dS in Setophaga, implying relatively strong selective pressures to overcome long-standing purifying selection. We studied the effects of each substitution on spectral tuning and found they do not cause large spectral shifts. Thus substitutions may reflect other aspects of opsin function, such as those affecting photosensitivity and/or dark-light adaptation. Although it is unclear what these alterations mean for color perception, we suggest that rapid evolution is linked to sexual selection, given the exceptional plumage colour diversification in Setophaga. PMID:25827331

Migration and the evolution of sexual dichromatism: evolutionary loss of female coloration with migration among wood-warblers.

PubMed

Simpson, Richard K; Johnson, Michele A; Murphy, Troy G

2015-06-22

The mechanisms underlying evolutionary changes in sexual dimorphism have long been of interest to biologists. A striking gradient in sexual dichromatism exists among songbirds in North America, including the wood-warblers (Parulidae): males are generally more colourful than females at northern latitudes, while the sexes are similarly ornamented at lower latitudes. We use phylogenetically controlled comparative analysis to test three non-mutually exclusive hypotheses for the evolution of sexual dichromatism among wood-warblers. The first two hypotheses focus on the loss of female coloration with the evolution of migration, either owing to the costs imposed by visual predators during migration, or owing to the relaxation of selection for female social signalling at higher latitudes. The third hypothesis focuses on whether sexual dichromatism evolved owing to changes in male ornamentation as the strength of sexual selection increases with breeding latitude. To test these hypotheses, we compared sexual dichromatism to three variables: the presence of migration, migration distance, and breeding latitude. We found that the presence of migration and migration distance were both positively correlated with sexual dichromatism, but models including breeding latitude alone were not strongly supported. Ancestral state reconstruction supports the hypothesis that the ancestral wood-warblers were monochromatic, with both colourful males and females. Combined, these results are consistent with the hypotheses that the evolution of migration is associated with the relaxation of selection for social signalling among females and that there are increased predatory costs along longer migratory routes for colourful females. These results suggest that loss of female ornamentation can be a driver of sexual dichromatism and that social or natural selection may be a stronger contributor to variation in dichromatism than sexual selection. © 2015 The Author(s) Published by the Royal Society

Commensal foraging by a fan-tailed warbler (Euthlypis lachrymosa) with a nine-banded armadillo (Dasypus nocemcinctus) in southwestern Mexico

Treesearch

Richard R. Schaefer; Jesse F. Fagan

2006-01-01

Many interspecific commensal foraging interactions involving birds have been documented. We describe an observation of commensal foraging by a fan-tailed warbler (Euthlypis lachrymosa) with a nine-banded armadillo (Dasypus novemcinctus) in Guerrero, southwestern Mexico. Our obsenation is similar to those reported from El Salvador...

Linking big models to big data: efficient ecosystem model calibration through Bayesian model emulation

NASA Astrophysics Data System (ADS)

Fer, I.; Kelly, R.; Andrews, T.; Dietze, M.; Richardson, A. D.

2016-12-01

Our ability to forecast ecosystems is limited by how well we parameterize ecosystem models. Direct measurements for all model parameters are not always possible and inverse estimation of these parameters through Bayesian methods is computationally costly. A solution to computational challenges of Bayesian calibration is to approximate the posterior probability surface using a Gaussian Process that emulates the complex process-based model. Here we report the integration of this method within an ecoinformatics toolbox, Predictive Ecosystem Analyzer (PEcAn), and its application with two ecosystem models: SIPNET and ED2.1. SIPNET is a simple model, allowing application of MCMC methods both to the model itself and to its emulator. We used both approaches to assimilate flux (CO2 and latent heat), soil respiration, and soil carbon data from Bartlett Experimental Forest. This comparison showed that emulator is reliable in terms of convergence to the posterior distribution. A 10000-iteration MCMC analysis with SIPNET itself required more than two orders of magnitude greater computation time than an MCMC run of same length with its emulator. This difference would be greater for a more computationally demanding model. Validation of the emulator-calibrated SIPNET against both the assimilated data and out-of-sample data showed improved fit and reduced uncertainty around model predictions. We next applied the validated emulator method to the ED2, whose complexity precludes standard Bayesian data assimilation. We used the ED2 emulator to assimilate demographic data from a network of inventory plots. For validation of the calibrated ED2, we compared the model to results from Empirical Succession Mapping (ESM), a novel synthesis of successional patterns in Forest Inventory and Analysis data. Our results revealed that while the pre-assimilation ED2 formulation cannot capture the emergent demographic patterns from ESM analysis, constrained model parameters controlling demographic

Idols as Sunshine or Road Signs: Comparing Absorption-Addiction Idolatry With Identification-Emulation Idolatry.

PubMed

Cheung, Chau-Kiu; Yue, Xiao Dong

2018-01-01

This study seeks to contrast absorption-addiction idolatry and identification-emulation idolatry. Whereas absorption-addiction idolatry progresses from entertainment/socializing to personalizing and obsession about the idol, identification-emulation idolatry unfolds in terms of identification, attachment, romantization, idealization, and consumption about the idol or his or her derivatives. Based on a sample of 1310 secondary school and university students in Hong Kong, the study verified the original factor model composed of five first-order identification-emulation idolatry and three first-order absorption-addiction idolatry factors, with the latter more predictable by fans' club membership.

Using a Gaussian Process Emulator for Data-driven Surrogate Modelling of a Complex Urban Drainage Simulator

NASA Astrophysics Data System (ADS)

Bellos, V.; Mahmoodian, M.; Leopold, U.; Torres-Matallana, J. A.; Schutz, G.; Clemens, F.

2017-12-01

Surrogate models help to decrease the run-time of computationally expensive, detailed models. Recent studies show that Gaussian Process Emulators (GPE) are promising techniques in the field of urban drainage modelling. However, this study focusses on developing a GPE-based surrogate model for later application in Real Time Control (RTC) using input and output time series of a complex simulator. The case study is an urban drainage catchment in Luxembourg. A detailed simulator, implemented in InfoWorks ICM, is used to generate 120 input-output ensembles, from which, 100 are used for training the emulator and 20 for validation of the results. An ensemble of historical rainfall events with 2 hours duration and 10 minutes time steps are considered as the input data. Two example outputs, are selected as wastewater volume and total COD concentration in a storage tank in the network. The results of the emulator are tested with unseen random rainfall events from the ensemble dataset. The emulator is approximately 1000 times faster than the original simulator for this small case study. Whereas the overall patterns of the simulator are matched by the emulator, in some cases the emulator deviates from the simulator. To quantify the accuracy of the emulator in comparison with the original simulator, Nash-Sutcliffe efficiency (NSE) between the emulator and simulator is calculated for unseen rainfall scenarios. The range of NSE for the case of tank volume is from 0.88 to 0.99 with a mean value of 0.95, whereas for COD is from 0.71 to 0.99 with a mean value of 0.92. The emulator is able to predict the tank volume with higher accuracy as the relationship between rainfall intensity and tank volume is linear. For COD, which has a non-linear behaviour, the predictions are less accurate and more uncertain, in particular when rainfall intensity increases. This predictions were improved by including a larger amount of training data for the higher rainfall intensities. It was observed

Quantum Emulation of Gravitational Waves.

PubMed

Fernandez-Corbaton, Ivan; Cirio, Mauro; Büse, Alexander; Lamata, Lucas; Solano, Enrique; Molina-Terriza, Gabriel

2015-07-14

Gravitational waves, as predicted by Einstein's general relativity theory, appear as ripples in the fabric of spacetime traveling at the speed of light. We prove that the propagation of small amplitude gravitational waves in a curved spacetime is equivalent to the propagation of a subspace of electromagnetic states. We use this result to propose the use of entangled photons to emulate the evolution of gravitational waves in curved spacetimes by means of experimental electromagnetic setups featuring metamaterials.

Microsatellite DNA markers for delineating population structure and kinship among the endangered Kirtland’s warbler (Dendroica kirtlandii)

Treesearch

TIM L. KING; MICHAEL S. EACKLES; ANNE P. HENDERSON; CAROL I. BOCETTI; DAVE CURRIE; JR WUNDERLE

2005-01-01

We document the isolation and characterization of 23 microsatellite DNA markers for the endangered Kirtland’s warbler (Dendroica kirtlandii), a Nearctic/Neotropical migrant passerine. This suite of markers revealed moderate to high levels of allelic diversity (averaging 7.7 alleles per locus) and heterozygosity (averaging 72%). Genotypic frequencies at 22 of 23 (95%)...

A proxy of social mate choice in prairie warblers is correlated with consistent, rapid, low-pitched singing

Treesearch

Bruce E. Byers; Michael E. Akresh; David I. King

2015-01-01

In songbirds, female mate choice may be influenced by how well a male performs his songs. Performing songs well may be especially difficult if it requires maximizingmultiple aspects of performance simultaneously.We therefore hypothesized that, in a population of prairie warblers, the males most attractive to females would be those with superior performance in more than...

Study of the potential impacts of highway construction on selected birds with emphasis on the golden-cheeked warbler : final report 2008-2011.

DOT National Transportation Integrated Search

2012-07-01

This report summarizes the 20082011 field seasons for the Highway 71 impact assessment of : highway construction noise and activity on golden-cheeked warblers (Setophaga chrysoparia). Researchers : examined if construction activity and noise alter...

Description of nests, eggs, and nestlings of the endangered nightingale reed-warbler on Saipan, Micronesia

USGS Publications Warehouse

Mosher, S.M.; Fancy, S.G.

2002-01-01

We describe the first verified nests, eggs, and nestlings of the Nightingale Reed-Warbler (Acrocephalus luscinia), an endangered species endemic to the Mariana Islands, Micronesia. Nest composition, nest dimensions, and eggs were studied on the island of Saipan. Nests were located within three habitat types: upland introduced tangantangan (Leucaena leucocephala) forest, a native mangrove (Bruguiera gymnorrhiza) wetland, and a native reed (Phragmites karka) wetland. Nesting substrates included five native and two introduced tree species and one native reed species. Nests were composed primarily of dry vine stems, needle-like branchlets of ironwood (Casuarina equisetifolia), and tangantangan petioles. Nests were compact to bulky in construction and were secured to a forked arrangement of branches or stems. The background color of eggs ranged from white to cream to ivory-buff. Eggs were spotted, speckled, and blotched with gray, brown, black, and rust colored markings. Clutch size was 2-4, with a mode of two. Hatchlings were altricial with closed eyelids and devoid of natal down with dark gray to black skin. Nestlings examined prior to fledging resembled the adult plumage, except for the lack of the yellow supercilium found in adults. The nests and eggs have some characteristics similar to those of other Acrocephaline warblers found throughout Micronesia and Polynesia.

User-Friendly Interface Developed for a Web-Based Service for SpaceCAL Emulations

NASA Technical Reports Server (NTRS)

Liszka, Kathy J.; Holtz, Allen P.

2004-01-01

A team at the NASA Glenn Research Center is developing a Space Communications Architecture Laboratory (SpaceCAL) for protocol development activities for coordinated satellite missions. SpaceCAL will provide a multiuser, distributed system to emulate space-based Internet architectures, backbone networks, formation clusters, and constellations. As part of a new effort in 2003, building blocks are being defined for an open distributed system to make the satellite emulation test bed accessible through an Internet connection. The first step in creating a Web-based service to control the emulation remotely is providing a user-friendly interface for encoding the data into a well-formed and complete Extensible Markup Language (XML) document. XML provides coding that allows data to be transferred between dissimilar systems. Scenario specifications include control parameters, network routes, interface bandwidths, delay, and bit error rate. Specifications for all satellite, instruments, and ground stations in a given scenario are also included in the XML document. For the SpaceCAL emulation, the XML document can be created using XForms, a Webbased forms language for data collection. Contrary to older forms technology, the interactive user interface makes the science prevalent, not the data representation. Required versus optional input fields, default values, automatic calculations, data validation, and reuse will help researchers quickly and accurately define missions. XForms can apply any XML schema defined for the test mission to validate data before forwarding it to the emulation facility. New instrument definitions, facilities, and mission types can be added to the existing schema. The first prototype user interface incorporates components for interactive input and form processing. Internet address, data rate, and the location of the facility are implemented with basic form controls with default values provided for convenience and efficiency using basic XForms operations

Emulation applied to reliability analysis of reconfigurable, highly reliable, fault-tolerant computing systems

NASA Technical Reports Server (NTRS)

Migneault, G. E.

1979-01-01

Emulation techniques applied to the analysis of the reliability of highly reliable computer systems for future commercial aircraft are described. The lack of credible precision in reliability estimates obtained by analytical modeling techniques is first established. The difficulty is shown to be an unavoidable consequence of: (1) a high reliability requirement so demanding as to make system evaluation by use testing infeasible; (2) a complex system design technique, fault tolerance; (3) system reliability dominated by errors due to flaws in the system definition; and (4) elaborate analytical modeling techniques whose precision outputs are quite sensitive to errors of approximation in their input data. Next, the technique of emulation is described, indicating how its input is a simple description of the logical structure of a system and its output is the consequent behavior. Use of emulation techniques is discussed for pseudo-testing systems to evaluate bounds on the parameter values needed for the analytical techniques. Finally an illustrative example is presented to demonstrate from actual use the promise of the proposed application of emulation.

Quantum Emulation of Gravitational Waves

PubMed Central

Fernandez-Corbaton, Ivan; Cirio, Mauro; Büse, Alexander; Lamata, Lucas; Solano, Enrique; Molina-Terriza, Gabriel

2015-01-01

Gravitational waves, as predicted by Einstein’s general relativity theory, appear as ripples in the fabric of spacetime traveling at the speed of light. We prove that the propagation of small amplitude gravitational waves in a curved spacetime is equivalent to the propagation of a subspace of electromagnetic states. We use this result to propose the use of entangled photons to emulate the evolution of gravitational waves in curved spacetimes by means of experimental electromagnetic setups featuring metamaterials. PMID:26169801

Statistical evaluation of metal fill widths for emulated metal fill in parasitic extraction methodology

NASA Astrophysics Data System (ADS)

J-Me, Teh; Noh, Norlaili Mohd.; Aziz, Zalina Abdul

2015-05-01

In the chip industry today, the key goal of a chip development organization is to develop and market chips within a short time frame to gain foothold on market share. This paper proposes a design flow around the area of parasitic extraction to improve the design cycle time. The proposed design flow utilizes the usage of metal fill emulation as opposed to the current flow which performs metal fill insertion directly. By replacing metal fill structures with an emulation methodology in earlier iterations of the design flow, this is targeted to help reduce runtime in fill insertion stage. Statistical design of experiments methodology utilizing the randomized complete block design was used to select an appropriate emulated metal fill width to improve emulation accuracy. The experiment was conducted on test cases of different sizes, ranging from 1000 gates to 21000 gates. The metal width was varied from 1 x minimum metal width to 6 x minimum metal width. Two-way analysis of variance and Fisher's least significant difference test were used to analyze the interconnect net capacitance values of the different test cases. This paper presents the results of the statistical analysis for the 45 nm process technology. The recommended emulated metal fill width was found to be 4 x the minimum metal width.

The Signi?cance of Emulation in the Oral Interaction between Teacher and Students

ERIC Educational Resources Information Center

Kindeberg, Tina

2013-01-01

The lack of attention to the role of emotions generally has led modern learning theories to neglect the importance of emulation as a pedagogical support to students' learning. One reason could be that the influence of teacher personality is not considered in relation to learning outcome. Another reason may be that the concept of emulation has been…

Differential autumn migration of the aquatic warbler Acrocephalus paludicola

NASA Astrophysics Data System (ADS)

Wojczulanis-Jakubas, Katarzyna; Jakubas, Dariusz; Foucher, Julien; Dziarska-Pałac, Joanna; Dugué, Hubert

2013-11-01

Relatively little attention has been paid to sex differences in the migration of birds in autumn. We studied the autumn migration strategy of molecularly sexed males and females in the globally threatened aquatic warbler Acrocephalus paludicola. We captured 176 birds at a stopover site in the Loire estuary at Donges, France. The median date for the passage of adults was 8 days earlier in males than females, although the timing of migration in first-year males and females was similar. This indicates that males, who are without parental duties, can start their migration earlier than females and first-year birds. Adults were significantly heavier than immature birds but did not have higher fat scores. In both age categories, more males (two to three times more) were captured. However, various factors (including tape-luring) can affect observed sex ratio.

The introspective may achieve more: Enhancing existing Geoscientific models with native-language emulated structural reflection

NASA Astrophysics Data System (ADS)

Ji, Xinye; Shen, Chaopeng

2018-01-01

Geoscientific models manage myriad and increasingly complex data structures as trans-disciplinary models are integrated. They often incur significant redundancy with cross-cutting tasks. Reflection, the ability of a program to inspect and modify its structure and behavior at runtime, is known as a powerful tool to improve code reusability, abstraction, and separation of concerns. Reflection is rarely adopted in high-performance Geoscientific models, especially with Fortran, where it was previously deemed implausible. Practical constraints of language and legacy often limit us to feather-weight, native-language solutions. We demonstrate the usefulness of a structural-reflection-emulating, dynamically-linked metaObjects, gd. We show real-world examples including data structure self-assembly, effortless input/output (IO) and upgrade to parallel I/O, recursive actions and batch operations. We share gd and a derived module that reproduces MATLAB-like structure in Fortran and C++. We suggest that both a gd representation and a Fortran-native representation are maintained to access the data, each for separate purposes. Embracing emulated reflection allows generically-written codes that are highly re-usable across projects.

Quantification of uncertainties in the tsunami hazard for Cascadia using statistical emulation

NASA Astrophysics Data System (ADS)

Guillas, S.; Day, S. J.; Joakim, B.

2016-12-01

We present new high resolution tsunami wave propagation and coastal inundation for the Cascadia region in the Pacific Northwest. The coseismic representation in this analysis is novel, and more realistic than in previous studies, as we jointly parametrize multiple aspects of the seabed deformation. Due to the large computational cost of such simulators, statistical emulation is required in order to carry out uncertainty quantification tasks, as emulators efficiently approximate simulators. The emulator replaces the tsunami model VOLNA by a fast surrogate, so we are able to efficiently propagate uncertainties from the source characteristics to wave heights, in order to probabilistically assess tsunami hazard for Cascadia. We employ a new method for the design of the computer experiments in order to reduce the number of runs while maintaining good approximations properties of the emulator. Out of the initial nine parameters, mostly describing the geometry and time variation of the seabed deformation, we drop two parameters since these turn out to not have an influence on the resulting tsunami waves at the coast. We model the impact of another parameter linearly as its influence on the wave heights is identified as linear. We combine this screening approach with the sequential design algorithm MICE (Mutual Information for Computer Experiments), that adaptively selects the input values at which to run the computer simulator, in order to maximize the expected information gain (mutual information) over the input space. As a result, the emulation is made possible and accurate. Starting from distributions of the source parameters that encapsulate geophysical knowledge of the possible source characteristics, we derive distributions of the tsunami wave heights along the coastline.

ATM LAN Emulation: Getting from Here to There.

ERIC Educational Resources Information Center

Learn, Larry L., Ed.

1995-01-01

Discusses current LAN (local area network) configuration and explains ATM (asynchronous transfer mode) as the future telecommunications transport. Highlights include LAN emulation, which enables the interconnection of legacy LANs and the new ATM environment; virtual LANs; broadcast servers; and standards. (LRW)

Investigation of hyper-NA scanner emulation for photomask CDU performance

NASA Astrophysics Data System (ADS)

Poortinga, Eric; Scheruebl, Thomas; Conley, Will; Sundermann, Frank

2007-02-01

As the semiconductor industry moves toward immersion lithography using numerical apertures above 1.0 the quality of the photomask becomes even more crucial. Photomask specifications are driven by the critical dimension (CD) metrology within the wafer fab. Knowledge of the CD values at resist level provides a reliable mechanism for the prediction of device performance. Ultimately, tolerances of device electrical properties drive the wafer linewidth specifications of the lithography group. Staying within this budget is influenced mainly by the scanner settings, resist process, and photomask quality. Tightening of photomask specifications is one mechanism for meeting the wafer CD targets. The challenge lies in determining how photomask level metrology results influence wafer level imaging performance. Can it be inferred that photomask level CD performance is the direct contributor to wafer level CD performance? With respect to phase shift masks, criteria such as phase and transmission control are generally tightened with each technology node. Are there other photomask relevant influences that effect wafer CD performance? A comprehensive study is presented supporting the use of scanner emulation based photomask CD metrology to predict wafer level within chip CD uniformity (CDU). Using scanner emulation with the photomask can provide more accurate wafer level prediction because it inherently includes all contributors to image formation related to the 3D topography such as the physical CD, phase, transmission, sidewall angle, surface roughness, and other material properties. Emulated images from different photomask types were captured to provide CD values across chip. Emulated scanner image measurements were completed using an AIMS TM45-193i with its hyper-NA, through-pellicle data acquisition capability including the Global CDU Map TM software option for AIMS TM tools. The through-pellicle data acquisition capability is an essential prerequisite for capturing final CDU

Fruit abundance and local distribution of wintering hermit thrushes (Catharus guttatus) and yellow-rumped warblers (Dendroica coronata) in South Carolina

Treesearch

Charles Kwit; Douglas J. Level; Cathryn H. Greenberg; Scott F. Pearson; John P. McCarty; Sarah Sargent; Ronald L. Mumme

2004-01-01

We conducted winter dcensuses of two short-distance migrants, Hermit thrushes (Catharus guttatus) and Yellow-rumped Warblers (Dendroica coronata), over seven years in five different habitats to determien whether their local abundance could be predicted by fruit pulp biomass. Sampled habitats were stands of upland and bottomland...

A Phase-Locked Loop Epilepsy Network Emulator.

PubMed

Watson, P D; Horecka, K M; Cohen, N J; Ratnam, R

2016-10-15

Most seizure forecasting employs statistical learning techniques that lack a representation of the network interactions that give rise to seizures. We present an epilepsy network emulator (ENE) that uses a network of interconnected phase-locked loops (PLLs) to model synchronous, circuit-level oscillations between electrocorticography (ECoG) electrodes. Using ECoG data from a canine-epilepsy model (Davis et al. 2011) and a physiological entropy measure (approximate entropy or ApEn, Pincus 1995), we demonstrate the entropy of the emulator phases increases dramatically during ictal periods across all ECoG recording sites and across all animals in the sample. Further, this increase precedes the observable voltage spikes that characterize seizure activity in the ECoG data. These results suggest that the ENE is sensitive to phase-domain information in the neural circuits measured by ECoG and that an increase in the entropy of this measure coincides with increasing likelihood of seizure activity. Understanding this unpredictable phase-domain electrical activity present in ECoG recordings may provide a target for seizure detection and feedback control.

A Phase-Locked Loop Epilepsy Network Emulator

PubMed Central

Watson, P.D.; Horecka, K. M.; Cohen, N.J.; Ratnam, R.

2015-01-01

Most seizure forecasting employs statistical learning techniques that lack a representation of the network interactions that give rise to seizures. We present an epilepsy network emulator (ENE) that uses a network of interconnected phase-locked loops (PLLs) to model synchronous, circuit-level oscillations between electrocorticography (ECoG) electrodes. Using ECoG data from a canine-epilepsy model (Davis et al. 2011) and a physiological entropy measure (approximate entropy or ApEn, Pincus 1995), we demonstrate the entropy of the emulator phases increases dramatically during ictal periods across all ECoG recording sites and across all animals in the sample. Further, this increase precedes the observable voltage spikes that characterize seizure activity in the ECoG data. These results suggest that the ENE is sensitive to phase-domain information in the neural circuits measured by ECoG and that an increase in the entropy of this measure coincides with increasing likelihood of seizure activity. Understanding this unpredictable phase-domain electrical activity present in ECoG recordings may provide a target for seizure detection and feedback control. PMID:26664133

Extreme MHC class I diversity in the sedge warbler (Acrocephalus schoenobaenus); selection patterns and allelic divergence suggest that different genes have different functions.

PubMed

Biedrzycka, Aleksandra; O'Connor, Emily; Sebastian, Alvaro; Migalska, Magdalena; Radwan, Jacek; Zając, Tadeusz; Bielański, Wojciech; Solarz, Wojciech; Ćmiel, Adam; Westerdahl, Helena

2017-07-05

Recent work suggests that gene duplications may play an important role in the evolution of immunity genes. Passerine birds, and in particular Sylvioidea warblers, have highly duplicated major histocompatibility complex (MHC) genes, which are key in immunity, compared to other vertebrates. However, reasons for this high MHC gene copy number are yet unclear. High-throughput sequencing (HTS) allows MHC genotyping even in individuals with extremely duplicated genes. This HTS data can reveal evidence of selection, which may help to unravel the putative functions of different gene copies, i.e. neofunctionalization. We performed exhaustive genotyping of MHC class I in a Sylvioidea warbler, the sedge warbler, Acrocephalus schoenobaenus, using the Illumina MiSeq technique on individuals from a wild study population. The MHC diversity in 863 genotyped individuals by far exceeds that of any other bird species described to date. A single individual could carry up to 65 different alleles, a large proportion of which are expressed (transcribed). The MHC alleles were of three different lengths differing in evidence of selection, diversity and divergence within our study population. Alleles without any deletions and alleles containing a 6 bp deletion showed characteristics of classical MHC genes, with evidence of multiple sites subject to positive selection and high sequence divergence. In contrast, alleles containing a 3 bp deletion had no sites subject to positive selection and had low divergence. Our results suggest that sedge warbler MHC alleles that either have no deletion, or contain a 6 bp deletion, encode classical antigen presenting MHC molecules. In contrast, MHC alleles containing a 3 bp deletion may encode molecules with a different function. This study demonstrates that highly duplicated MHC genes can be characterised with HTS and that selection patterns can be useful for revealing neofunctionalization. Importantly, our results highlight the need to consider the

Genetic variation and seasonal migratory connectivity in Wilson's warblers (Wilsonia pusilla): species-level differences in nuclear DNA between western and eastern populations.

PubMed

Irwin, Darren E; Irwin, Jessica H; Smith, Thomas B

2011-08-01

There is growing interest in understanding patterns of seasonal migratory connectivity between breeding and wintering sites, both because differences in migratory behaviour can be associated with population differentiation and because knowledge of migratory connectivity is essential for understanding the ecology, evolution and conservation of migratory species. We present the first broad survey of geographic variation in the nuclear genome of breeding and wintering Wilson's warblers (Wilsonia pusilla), which have previously served as a research system for the study of whether genetic markers and isotopes can reveal patterns of migratory connectivity. Using 153 samples surveyed at up to 257 variable amplified fragment length polymorphism markers, we show that Wilson's warblers consist of highly distinct western and eastern breeding groups, with all winter samples grouping with the western breeding group. Within the west, there is weak geographic differentiation, at a level insufficient for use in the assignment of wintering samples to specific areas. The distinctiveness of western and eastern genetic groups, with no known intermediates, strongly suggests that these two groups are cryptic species. Analysis of mitochondrial cytochrome b sequence variation shows that the estimated coalescence time between western and eastern clades is approximately 2.3 Ma, a surprisingly old time of divergence that is more typical of distinct species than of subspecies. Given their morphological similarity but strong genetic differences, western and eastern Wilson's warblers present a likely case of association between divergence in migratory behaviour and the process of speciation. © 2011 Blackwell Publishing Ltd.

The potential role of hurricanes in the creation and maintenance of Kirtland's warbler winter habitat in the Bahamian Archipelago.

Treesearch

Joseph Wunderle; David Currie; David N. Ewert

2007-01-01

The threatened migratory Kirtland’s Warbler (KW, Dendorica kirtlandii) breeds exclusively in Michigan and overwinters nearly exclusively in the Bahamas Archipelago, where little is known of its winter habitat. Previous observations and our own studies indicate that KWs routinely use early successional or regenerating shrubby habitats on Eleuthera. Our preliminary...

Emulation: A fast stochastic Bayesian method to eliminate model space

NASA Astrophysics Data System (ADS)

Roberts, Alan; Hobbs, Richard; Goldstein, Michael

2010-05-01

Joint inversion of large 3D datasets has been the goal of geophysicists ever since the datasets first started to be produced. There are two broad approaches to this kind of problem, traditional deterministic inversion schemes and more recently developed Bayesian search methods, such as MCMC (Markov Chain Monte Carlo). However, using both these kinds of schemes has proved prohibitively expensive, both in computing power and time cost, due to the normally very large model space which needs to be searched using forward model simulators which take considerable time to run. At the heart of strategies aimed at accomplishing this kind of inversion is the question of how to reliably and practicably reduce the size of the model space in which the inversion is to be carried out. Here we present a practical Bayesian method, known as emulation, which can address this issue. Emulation is a Bayesian technique used with considerable success in a number of technical fields, such as in astronomy, where the evolution of the universe has been modelled using this technique, and in the petroleum industry where history matching is carried out of hydrocarbon reservoirs. The method of emulation involves building a fast-to-compute uncertainty-calibrated approximation to a forward model simulator. We do this by modelling the output data from a number of forward simulator runs by a computationally cheap function, and then fitting the coefficients defining this function to the model parameters. By calibrating the error of the emulator output with respect to the full simulator output, we can use this to screen out large areas of model space which contain only implausible models. For example, starting with what may be considered a geologically reasonable prior model space of 10000 models, using the emulator we can quickly show that only models which lie within 10% of that model space actually produce output data which is plausibly similar in character to an observed dataset. We can thus much

Deep Neural Network Emulation of a High-Order, WENO-Limited, Space-Time Reconstruction

NASA Astrophysics Data System (ADS)

Norman, M. R.; Hall, D. M.

2017-12-01

Deep Neural Networks (DNNs) have been used to emulate a number of processes in atmospheric models, including radiation and even so-called super-parameterization of moist convection. In each scenario, the DNN provides a good representation of the process even for inputs that have not been encountered before. More notably, they provide an emulation at a fraction of the cost of the original routine, giving speed-ups of 30× and even up to 200× compared to the runtime costs of the original routines. However, to our knowledge there has not been an investigation into using DNNs to emulate the dynamics. The most likely reason for this is that dynamics operators are typically both linear and low cost, meaning they cannot be sped up by a non-linear DNN emulation. However, there exist high-cost non-linear space-time dynamics operators that significantly reduce the number of parallel data transfers necessary to complete an atmospheric simulation. The WENO-limited Finite-Volume method with ADER-DT time integration is a prime example of this - needing only two parallel communications per large, fully limited time step. However, it comes at a high cost in terms of computation, which is why many would hesitate to use it. This talk investigates DNN emulation of the WENO-limited space-time finite-volume reconstruction procedure - the most expensive portion of this method, which densely clusters a large amount of non-linear computation. Different training techniques and network architectures are tested, and the accuracy and speed-up of each is given.

An emulator for minimizing finite element analysis implementation resources

NASA Technical Reports Server (NTRS)

Melosh, R. J.; Utku, S.; Salama, M.; Islam, M.

1982-01-01

A finite element analysis emulator providing a basis for efficiently establishing an optimum computer implementation strategy when many calculations are involved is described. The SCOPE emulator determines computer resources required as a function of the structural model, structural load-deflection equation characteristics, the storage allocation plan, and computer hardware capabilities. Thereby, it provides data for trading analysis implementation options to arrive at a best strategy. The models contained in SCOPE lead to micro-operation computer counts of each finite element operation as well as overall computer resource cost estimates. Application of SCOPE to the Memphis-Arkansas bridge analysis provides measures of the accuracy of resource assessments. Data indicate that predictions are within 17.3 percent for calculation times and within 3.2 percent for peripheral storage resources for the ELAS code.

Multi-level emulation of complex climate model responses to boundary forcing data

NASA Astrophysics Data System (ADS)

Tran, Giang T.; Oliver, Kevin I. C.; Holden, Philip B.; Edwards, Neil R.; Sóbester, András; Challenor, Peter

2018-04-01

Climate model components involve both high-dimensional input and output fields. It is desirable to efficiently generate spatio-temporal outputs of these models for applications in integrated assessment modelling or to assess the statistical relationship between such sets of inputs and outputs, for example, uncertainty analysis. However, the need for efficiency often compromises the fidelity of output through the use of low complexity models. Here, we develop a technique which combines statistical emulation with a dimensionality reduction technique to emulate a wide range of outputs from an atmospheric general circulation model, PLASIM, as functions of the boundary forcing prescribed by the ocean component of a lower complexity climate model, GENIE-1. Although accurate and detailed spatial information on atmospheric variables such as precipitation and wind speed is well beyond the capability of GENIE-1's energy-moisture balance model of the atmosphere, this study demonstrates that the output of this model is useful in predicting PLASIM's spatio-temporal fields through multi-level emulation. Meaningful information from the fast model, GENIE-1 was extracted by utilising the correlation between variables of the same type in the two models and between variables of different types in PLASIM. We present here the construction and validation of several PLASIM variable emulators and discuss their potential use in developing a hybrid model with statistical components.

[Book review] The Kirtland's Warbler: The Story of a Bird's Fight against extinction and the People Who Saved It

Treesearch

Deahn M. Donner

2013-01-01

The population recovery of Kirtland's Warbler (Setophaga kirtlandii) is one of the most fascinating success stories of an endangered species in the past 60 years. As the author states, the story transcends the bird and its environment. By including the human dimension of recovery efforts, this book keeps the reader involved throughout what ends...

Development of the CELSS emulator at NASA. Johnson Space Center

NASA Technical Reports Server (NTRS)

Cullingford, Hatice S.

1990-01-01

The Closed Ecological Life Support System (CELSS) Emulator is under development. It will be used to investigate computer simulations of integrated CELSS operations involving humans, plants, and process machinery. Described here is Version 1.0 of the CELSS Emulator that was initiated in 1988 on the Johnson Space Center (JSC) Multi Purpose Applications Console Test Bed as the simulation framework. The run model of the simulation system now contains a CELSS model called BLSS. The CELSS simulator empowers us to generate model data sets, store libraries of results for further analysis, and also display plots of model variables as a function of time. The progress of the project is presented with sample test runs and simulation display pages.

Effects of prescribed fire on fuels, vegetation, and Golden-cheeked Warbler (Setophaga chrysoparia) demographics in Texas juniper-oak woodlands

Treesearch

Jennifer L. Reidy; Frank R., III Thompson; Carl Schwope; Scott Rowin; James M. Mueller

2016-01-01

The Golden-cheeked Warbler (Setophaga chrysoparia) is an endangered songbird that breeds in mature juniper-oak woodlands restricted to Central Texas. This habitat is increasingly susceptible to crown fire due to climate change, land use change, and fire suppression. Prescribed fire is a potential tool to reduce the risk of crown fire and may be a...

Emulation, imitation, over-imitation and the scope of culture for child and chimpanzee

PubMed Central

Whiten, Andrew; McGuigan, Nicola; Marshall-Pescini, Sarah; Hopper, Lydia M.

2009-01-01

We describe our recent studies of imitation and cultural transmission in chimpanzees and children, which question late twentieth-century characterizations of children as imitators, but chimpanzees as emulators. As emulation entails learning only about the results of others' actions, it has been thought to curtail any capacity to sustain cultures. Recent chimpanzee diffusion experiments have by contrast documented a significant capacity for copying local behavioural traditions. Additionally, in recent ‘ghost’ experiments with no model visible, chimpanzees failed to replicate the object movements on which emulation is supposed to focus. We conclude that chimpanzees rely more on imitation and have greater cultural capacities than previously acknowledged. However, we also find that they selectively apply a range of social learning processes that include emulation. Recent studies demonstrating surprisingly unselective ‘over-imitation’ in children suggest that children's propensity to imitate has been underestimated too. We discuss the implications of these developments for the nature of social learning and culture in the two species. Finally, our new experiments directly address cumulative cultural learning. Initial results demonstrate a relative conservatism and conformity in chimpanzees' learning, contrasting with cumulative cultural learning in young children. This difference may contribute much to the contrast in these species' capacities for cultural evolution. PMID:19620112

Emotions Targeting Moral Exemplarity: Making Sense of the Logical Geography of Admiration, Emulation and Elevation

ERIC Educational Resources Information Center

Kristjánsson, Kristján

2017-01-01

Despite renewed interest in moral role-modelling and its emotional underpinnings, further conceptual work is needed on the logical geography of the emotions purportedly driving it, in particular, admiration, emulation and elevation. In this article, I explore admiration (as understood by Linda Zagzebski), emulation (as understood by Aristotle) and…

Knowing for Nursing Practice: Patterns of Knowledge and Their Emulation in Expert Systems

PubMed Central

Abraham, Ivo L.; Fitzpatrick, Joyce J.

1987-01-01

This paper addresses the issue of clinical knowledge in nursing, and the feasibility of emulating this knowledge into expert system technology. The perspective on patterns of knowing for nursing practice, advanced by Carper (1978), serves as point of departure. The four patterns of knowing -- empirics, esthetics, ethics, personal knowledge -- are evaluated as to the extent to which they can be emulated in clinical expert systems, given constraints imposed by the current technology of these systems.

On the importance of the Cerulean and Golden-winged Warblers summits in the National Federation of Coffee Growers of Colombia in Bogotá

Treesearch

Paul B. Hamel

2008-01-01

Cerulean Warbler is a bird with problems; this migratorybird lives in environments on which large numbersof people depend for an adequate productivelivelihood, energy, high quality wood products, coffee,and cacao. Solving the biological problems of thisspecies in its complex...

Copy of Using Emulation and Simulation to Understand the Large-Scale Behavior of the Internet.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adalsteinsson, Helgi; Armstrong, Robert C.; Chiang, Ken

2008-10-01

We report on the work done in the late-start LDRDUsing Emulation and Simulation toUnderstand the Large-Scale Behavior of the Internet. We describe the creation of a researchplatform that emulates many thousands of machines to be used for the study of large-scale inter-net behavior. We describe a proof-of-concept simple attack we performed in this environment.We describe the successful capture of a Storm bot and, from the study of the bot and furtherliterature search, establish large-scale aspects we seek to understand via emulation of Storm onour research platform in possible follow-on work. Finally, we discuss possible future work.3

The introspective may achieve more: Enhancing existing Geoscientific models with native-language emulated structural reflection

DOE PAGES

Ji, Xinye; Shen, Chaopeng

2017-09-28

Geoscientific models manage myriad and increasingly complex data structures as trans-disciplinary models are integrated. They often incur significant redundancy with cross-cutting tasks. Reflection, the ability of a program to inspect and modify its structure and behavior at runtime, is known as a powerful tool to improve code reusability, abstraction, and separation of concerns. Reflection is rarely adopted in high-performance Geoscientific models, especially with Fortran, where it was previously deemed implausible. Practical constraints of language and legacy often limit us to feather-weight, native-language solutions. We demonstrate the usefulness of a structural-reflection-emulating, dynamically-linked metaObjects, gd. We show real-world examples including data structuremore » self-assembly, effortless save/restart and upgrade to parallel I/O, recursive actions and batch operations. We share gd and a derived module that reproduces MATLAB-like structure in Fortran and C++. We suggest that both a gd representation and a Fortran-native representation are maintained to access the data, each for separate purposes. In conclusion, embracing emulated reflection allows generically-written codes that are highly re-usable across projects.« less

The introspective may achieve more: Enhancing existing Geoscientific models with native-language emulated structural reflection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ji, Xinye; Shen, Chaopeng

Geoscientific models manage myriad and increasingly complex data structures as trans-disciplinary models are integrated. They often incur significant redundancy with cross-cutting tasks. Reflection, the ability of a program to inspect and modify its structure and behavior at runtime, is known as a powerful tool to improve code reusability, abstraction, and separation of concerns. Reflection is rarely adopted in high-performance Geoscientific models, especially with Fortran, where it was previously deemed implausible. Practical constraints of language and legacy often limit us to feather-weight, native-language solutions. We demonstrate the usefulness of a structural-reflection-emulating, dynamically-linked metaObjects, gd. We show real-world examples including data structuremore » self-assembly, effortless save/restart and upgrade to parallel I/O, recursive actions and batch operations. We share gd and a derived module that reproduces MATLAB-like structure in Fortran and C++. We suggest that both a gd representation and a Fortran-native representation are maintained to access the data, each for separate purposes. In conclusion, embracing emulated reflection allows generically-written codes that are highly re-usable across projects.« less

Low-warming Scenarios and their Approximation: Testing Emulation Performance for Average and Extreme Variables

NASA Astrophysics Data System (ADS)

Tebaldi, C.; Knutti, R.; Armbruster, A.

2017-12-01

Taking advantage of the availability of ensemble simulations under low-warming scenarios performed with NCAR-DOE CESM, we test the performance of established methods for climate model output emulation. The goal is to provide a green, yellow or red light to the large impact research community that may be interested in performing impact analysis using climate model output other than, or in conjunction with, CESM's, especially as the IPCC Special Report on the 1.5 target urgently calls for scientific contributions exploring the costs and benefits of attaining these ambitious goals. We test the performance of emulators of average temperature and precipitation - and their interannual variability - and we also explore the possibility of emulating indices of extremes (ETCCDI indices), devised to offer impact relevant information from daily output of temperature and precipitation. Different degrees of departure from the linearity assumed in these traditional emulation approaches are found across the various quantities considered, and across regions, highlighting different degrees of quality in the approximations, and therefore some challenges in the provision of climate change information for impact analysis under these new scenarios that not many models have thus far targeted through their simulations.

Performance tests of a power-electronics converter for multi-megawatt wind turbines using a grid emulator

NASA Astrophysics Data System (ADS)

Rizqy Averous, Nurhan; Berthold, Anica; Schneider, Alexander; Schwimmbeck, Franz; Monti, Antonello; De Doncker, Rik W.

2016-09-01

A vast increase of wind turbines (WT) contribution in the modern electrical grids have led to the development of grid connection requirements. In contrast to the conventional test method, testing power-electronics converters for WT using a grid emulator at Center for Wind Power Drives (CWD) RWTH Aachen University offers more flexibility for conducting test scenarios. Further analysis on the performance of the device under test (DUT) is however required when testing with grid emulator since the characteristic of the grid emulator might influence the performance of the DUT. This paper focuses on the performance analysis of the DUT when tested using grid emulator. Beside the issue regarding the current harmonics, the performance during Fault Ride-Through (FRT) is discussed in detail. A power hardware in the loop setup is an attractive solution to conduct a comprehensive study on the interaction between the power-electronics converters and the electrical grids.

Breeding biology of the Three-striped warbler in Venezuela: A contrast between tropical and temperate parulids

USGS Publications Warehouse

Cox, W.A.; Martin, T.E.

2009-01-01

We document reproductive life history traits of the Three-striped Warbler (Basileuterus tristriatus) from 146 nests in Venezuela and compare our results to data from the literature for other tropical and temperate parulid species. Mean (?? SE) clutch size was 1.96 ?? 0.03 eggs (n = 96) and fresh egg mass was 2.09 ?? 0.02 g. The incubation period was 15.8 ?? 0.2 days (n = 23) and the nestling period was 10.5 ?? 0.3 days (n = 12). Males did not incubate and rarely provided food for females during incubation. Females had 57 ?? 2% (n = 49) nest attentiveness (% of time on the nest incubating), which caused egg temperature to commonly become cold relative to development. Both adults fed nestlings and feeding rates increased with nestling age. The growth rate constant for nestlings based on mass was K 0.490, which is slower than for north temperate warblers. Predation was the primary source of nest failure and only 22% of nests were successful based on a Mayfield daily predation rate of 0.048 ?? 0.006. Our literature review indicates parulids differ strongly in life histories between temperate and tropical/subtropical sites with species in the tropics having, on average, smaller clutches, longer incubation periods, lower nest attentiveness, longer off-bouts, and longer nestling periods. ?? 2009 by the Wilson Ornithological Society.

Emulating weak localization using a solid-state quantum circuit.

PubMed

Chen, Yu; Roushan, P; Sank, D; Neill, C; Lucero, Erik; Mariantoni, Matteo; Barends, R; Chiaro, B; Kelly, J; Megrant, A; Mutus, J Y; O'Malley, P J J; Vainsencher, A; Wenner, J; White, T C; Yin, Yi; Cleland, A N; Martinis, John M

2014-10-14

Quantum interference is one of the most fundamental physical effects found in nature. Recent advances in quantum computing now employ interference as a fundamental resource for computation and control. Quantum interference also lies at the heart of sophisticated condensed matter phenomena such as Anderson localization, phenomena that are difficult to reproduce in numerical simulations. Here, employing a multiple-element superconducting quantum circuit, with which we manipulate a single microwave photon, we demonstrate that we can emulate the basic effects of weak localization. By engineering the control sequence, we are able to reproduce the well-known negative magnetoresistance of weak localization as well as its temperature dependence. Furthermore, we can use our circuit to continuously tune the level of disorder, a parameter that is not readily accessible in mesoscopic systems. Demonstrating a high level of control, our experiment shows the potential for employing superconducting quantum circuits as emulators for complex quantum phenomena.

Population distribution, density and habitat preference of the Cerulean Warbler (Setophaga cerulea) in the Delaware Water Gap National Recreation Area

Treesearch

Shannon Curley; Terry Master; Gregory George

2012-01-01

The breeding range of the Cerulean Warbler has expanded into second-growth forest and converted agricultural land in the northeastern United States where, according to the North American Breeding Bird Survey, the population is increasing. Despite this expansion in one part of its range, the population as a whole is still in rapid decline implying that habitat quality...

Memristors with diffusive dynamics as synaptic emulators for neuromorphic computing

DOE PAGES

Wang, Zhongrui; Joshi, Saumil; Savel’ev, Sergey E.; ...

2016-09-26

The accumulation and extrusion of Ca 2+ in the pre- and postsynaptic compartments play a critical role in initiating plastic changes in biological synapses. In order to emulate this fundamental process in electronic devices, we developed diffusive Ag-in-oxide memristors with a temporal response during and after stimulation similar to that of the synaptic Ca 2+ dynamics. In situ high-resolution transmission electron microscopy and nanoparticle dynamics simulations both demonstrate that Ag atoms disperse under electrical bias and regroup spontaneously under zero bias because of interfacial energy minimization, closely resembling synaptic influx and extrusion of Ca 2+, respectively. Furthermore, the diffusive memristormore » and its dynamics enable a direct emulation of both short- and long-term plasticity of biological synapses, representing an advance in hardware implementation of neuromorphic functionalities.« less

Statistical emulators of maize, rice, soybean and wheat yields from global gridded crop models

DOE PAGES

Blanc, Élodie

2017-01-26

This study provides statistical emulators of crop yields based on global gridded crop model simulations from the Inter-Sectoral Impact Model Intercomparison Project Fast Track project. The ensemble of simulations is used to build a panel of annual crop yields from five crop models and corresponding monthly summer weather variables for over a century at the grid cell level globally. This dataset is then used to estimate, for each crop and gridded crop model, the statistical relationship between yields, temperature, precipitation and carbon dioxide. This study considers a new functional form to better capture the non-linear response of yields to weather,more » especially for extreme temperature and precipitation events, and now accounts for the effect of soil type. In- and out-of-sample validations show that the statistical emulators are able to replicate spatial patterns of yields crop levels and changes overtime projected by crop models reasonably well, although the accuracy of the emulators varies by model and by region. This study therefore provides a reliable and accessible alternative to global gridded crop yield models. By emulating crop yields for several models using parsimonious equations, the tools provide a computationally efficient method to account for uncertainty in climate change impact assessments.« less

Statistical emulators of maize, rice, soybean and wheat yields from global gridded crop models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blanc, Élodie

This study provides statistical emulators of crop yields based on global gridded crop model simulations from the Inter-Sectoral Impact Model Intercomparison Project Fast Track project. The ensemble of simulations is used to build a panel of annual crop yields from five crop models and corresponding monthly summer weather variables for over a century at the grid cell level globally. This dataset is then used to estimate, for each crop and gridded crop model, the statistical relationship between yields, temperature, precipitation and carbon dioxide. This study considers a new functional form to better capture the non-linear response of yields to weather,more » especially for extreme temperature and precipitation events, and now accounts for the effect of soil type. In- and out-of-sample validations show that the statistical emulators are able to replicate spatial patterns of yields crop levels and changes overtime projected by crop models reasonably well, although the accuracy of the emulators varies by model and by region. This study therefore provides a reliable and accessible alternative to global gridded crop yield models. By emulating crop yields for several models using parsimonious equations, the tools provide a computationally efficient method to account for uncertainty in climate change impact assessments.« less

Aviation Communications Emulation Testbed

NASA Technical Reports Server (NTRS)

Sheehe, Charles; Mulkerin, Tom

2004-01-01

Aviation related applications that rely upon datalink for information exchange are increasingly being developed and deployed. The increase in the quantity of applications and associated data communications will expose problems and issues to resolve. NASA Glenn Research Center has prepared to study the communications issues that will arise as datalink applications are employed within the National Airspace System (NAS) by developing a aviation communications emulation testbed. The Testbed is evolving and currently provides the hardware and software needed to study the communications impact of Air Traffic Control (ATC) and surveillance applications in a densely populated environment. The communications load associated with up to 160 aircraft transmitting and receiving ATC and surveillance data can be generated in real time in a sequence similar to what would occur in the NAS.

Compact first and second order polarization mode dispersion emulator

NASA Astrophysics Data System (ADS)

Zhang, Yang; Li, Shiguang; Yang, Changxi

2005-08-01

We propose a 1st and 2nd order polarization mode dispersion emulator (PMDE) with one variable differential group delay (DGD) element using birefringence crystals and four polarization controllers (PCs). Monte Carlo simulations demonstrate that the output 1st and 2nd order polarization mode dispersion (PMD) generated by the PMDE consists with statistic theory. Compared with former PMDEs, this design is tunable, lower-cost, and more integrated for fabrication, which shows response time of 150 ?s, response frequency of 3.8 kHz, working wavelength of 1550 nm, total power consumption of less than 3 W, working range of 0---84 ps and 0---3600 ps2 for 1st and 2nd order PMD emulation, respectively. Also, it is programmable and can be controlled by either singlechip or computer. It can be applied to study the outage probability of optical communication systems due to PMD effect and the effectiveness of PMD compensation.

Silviculture for a declining species, Cerulean Warbler: 10-year results of a pilot study in the Mississippi Alluvial Valley

Treesearch

Paul B. Hamel; Mike Staten; Ray Souter; Carl G. Smith III; Gene Holland

2016-01-01

We report on the current status of a long-term study of Cerulean Warbler (Setophaga cerulea) response to silviculture on a 58-ha tract in Desha County, Arkansas. The work involved a 10 year premanipulation monitoring of the birds on the tract, followed by implementation of a split plot comparison of alternative treatments, each applied to a randomly selected half of...

Feasibility and reliability of using an exoskeleton to emulate muscle contractures during walking.

PubMed

Attias, M; Bonnefoy-Mazure, A; De Coulon, G; Cheze, L; Armand, S

2016-10-01

Contracture is a permanent shortening of the muscle-tendon-ligament complex that limits joint mobility. Contracture is involved in many diseases (cerebral palsy, stroke, etc.) and can impair walking and other activities of daily living. The purpose of this study was to quantify the reliability of an exoskeleton designed to emulate lower limb muscle contractures unilaterally and bilaterally during walking. An exoskeleton was built according to the following design criteria: adjustable to different morphologies; respect of the principal lines of muscular actions; placement of reflective markers on anatomical landmarks; and the ability to replicate the contractures of eight muscles of the lower limb unilaterally and bilaterally (psoas, rectus femoris, hamstring, hip adductors, gastrocnemius, soleus, tibialis posterior, and peroneus). Sixteen combinations of contractures were emulated on the unilateral and bilateral muscles of nine healthy participants. Two sessions of gait analysis were performed at weekly intervals to assess the reliability of the emulated contractures. Discrete variables were extracted from the kinematics to analyse the reliability. The exoskeleton did not affect normal walking when contractures were not emulated. Kinematic reliability varied from poor to excellent depending on the targeted muscle. Reliability was good for the bilateral and unilateral gastrocnemius, soleus, and tibialis posterior as well as the bilateral hamstring and unilateral hip adductors. The exoskeleton can be used to replicate contracture on healthy participants. The exoskeleton will allow us to differentiate primary and compensatory effects of muscle contractures on gait kinematics. Copyright © 2016 Elsevier B.V. All rights reserved.

Contrasting results from GWAS and QTL mapping on wing length in great reed warblers.

PubMed

Hansson, Bengt; Sigeman, Hanna; Stervander, Martin; Tarka, Maja; Ponnikas, Suvi; Strandh, Maria; Westerdahl, Helena; Hasselquist, Dennis

2018-04-15

A major goal in evolutionary biology is to understand the genetic basis of adaptive traits. In migratory birds, wing morphology is such a trait. Our previous work on the great reed warbler (Acrocephalus arundinaceus) shows that wing length is highly heritable and under sexually antagonistic selection. Moreover, a quantitative trait locus (QTL) mapping analysis detected a pronounced QTL for wing length on chromosome 2, suggesting that wing morphology is partly controlled by genes with large effects. Here, we re-evaluate the genetic basis of wing length in great reed warblers using a genomewide association study (GWAS) approach based on restriction site-associated DNA sequencing (RADseq) data. We use GWAS models that account for relatedness between individuals and include covariates (sex, age and tarsus length). The resulting association landscape was flat with no peaks on chromosome 2 or elsewhere, which is in line with expectations for polygenic traits. Analysis of the distribution of p-values did not reveal biases, and the inflation factor was low. Effect sizes were however not uniformly distributed on some chromosomes, and the Z chromosome had weaker associations than autosomes. The level of linkage disequilibrium (LD) in the population decayed to background levels within c. 1 kbp. There could be several reasons to why our QTL study and GWAS gave contrasting results including differences in how associations are modelled (cosegregation in pedigree vs. LD associations), how covariates are accounted for in the models, type of marker used (multi- vs. biallelic), difference in power or a combination of these. Our study highlights that the genetic architecture even of highly heritable traits is difficult to characterize in wild populations. © 2018 John Wiley & Sons Ltd.

Performance Guaranteed Inertia Emulation forDiesel-Wind System Feed Microgrid via ModelReference Control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melin, Alexander M.; Zhang, Yichen; Djouadi, Seddik

In this paper, a model reference control based inertia emulation strategy is proposed. Desired inertia can be precisely emulated through this control strategy so that guaranteed performance is ensured. A typical frequency response model with parametrical inertia is set to be the reference model. A measurement at a specific location delivers the information of disturbance acting on the diesel-wind system to the referencemodel. The objective is for the speed of the diesel-wind system to track the reference model. Since active power variation is dominantly governed by mechanical dynamics and modes, only mechanical dynamics and states, i.e., a swing-engine-governor system plusmore » a reduced-order wind turbine generator, are involved in the feedback control design. The controller is implemented in a three-phase diesel-wind system feed microgrid. The results show exact synthetic inertia is emulated, leading to guaranteed performance and safety bounds.« less

Songbirds in managed and non-managed savannas and woodlands in the central hardwoods region

Treesearch

Frank R., III Thompson; Jennifer L. Reidy; Sarah W. Kendrick; Jane A. Fitzgerald

2012-01-01

We know little about the response of birds to savanna and woodland restoration in the Ozarks or how important such habitats are to birds of conservation concern. Bird species such as red-headed woodpecker, prairie warbler, field sparrow, and blue-winged warbler are species of regional concern, and declines of these species may be due to historical declines in savannas...

Sex and age differences in site fidelity, food resource tracking, and body condition of wintering Kirtland's Warblers (Setophaga Kirtlandii) in the Bahamas

Treesearch

Joseph M. Wunderle, Jr.; Patricia K. Lebow; Jennifer D. White; Dave Currie; David N. Ewert

2014-01-01

Distribution of nonbreeding migrant birds in relation to variation in food availability has been hypothesized to result from the interaction of dominance hierarchies and variable movement responses, which together may have sex- and age-specific consequences. We predicted that site fidelity, movements, and abundance of Kirtland’s Warblers (Setophaga kirtlandii...

Recent status and trends of the land bird avifauna on Saipan, Mariana Islands, with emphasis on the endangered Nightingale Reed-warbler Acrocephalus luscinia

USGS Publications Warehouse

Camp, R.J.; Pratt, T.K.; Marshall, A.P.; Amidon, F.; Williams, L.L.

2009-01-01

The avifauna of the Mariana Islands, an archipelago in the western Pacific, faces the threats of rapid economic development and the spread of non-native species, particularly a devastating predator, Brown Tree Snake Boiga irregularis. In this paper, we examine the status and trends of the land bird fauna of Saipan Island based on three island-wide surveys conducted in 1982, 1997, and 2007. During this period, the human population on Saipan increased more than four-fold and much of the island has been developed. The surveys employed standard point-transect methods based on Distance Sampling. Remarkably, we found nearly all species of land birds - 11 native species and three introduced species - to be common or abundant. The exception was the Micronesian Megapode Megapodius laperouse, a historically rare species that was not observed on the 2007 survey, although it does persist on Saipan and other Mariana islands. A comparison of species densities among the three surveys showed that seven species, mainly fruit and seed-eaters, had increased and three species of insectivorous birds had decreased - Rufous Fantail Rhipidura rufifrons, Nightingale Reed-warbler Acrocephalus luscinia, and Golden White-eye Cleptornis marchei. Of these three, Nightingale Reed-warbler is listed as Endangered on the IUCN Red List and as an Endangered Species by the U.S. Fish and Wildlife Service. Reed-warbler densities on Saipan decreased by more than half between 1982 and 2007. Although point transect sampling worked well for this species, density estimates and trends assessment could be improved by reallocating sampling stations among habitats and by more frequent sampling. ?? BirdLife International 2009.

The use of emulator-based simulators for on-board software maintenance

NASA Astrophysics Data System (ADS)

Irvine, M. M.; Dartnell, A.

2002-07-01

Traditionally, onboard software maintenance activities within the space sector are performed using hardware-based facilities. These facilities are developed around the use of hardware emulation or breadboards containing target processors. Some sort of environment is provided around the hardware to support the maintenance actives. However, these environments are not easy to use to set-up the required test scenarios, particularly when the onboard software executes in a dynamic I/O environment, e.g. attitude control software, or data handling software. In addition, the hardware and/or environment may not support the test set-up required during investigations into software anomalies, e.g. raise spurious interrupt, fail memory, etc, and the overall "visibility" of the software executing may be limited. The Software Maintenance Simulator (SOMSIM) is a tool that can support the traditional maintenance facilities. The following list contains some of the main benefits that SOMSIM can provide: Low cost flexible extension to existing product - operational simulator containing software processor emulator; System-level high-fidelity test-bed in which software "executes"; Provides a high degree of control/configuration over the entire "system", including contingency conditions perhaps not possible with real hardware; High visibility and control over execution of emulated software. This paper describes the SOMSIM concept in more detail, and also describes the SOMSIM study being carried out for ESA/ESOC by VEGA IT GmbH.

Microwave emulations and tight-binding calculations of transport in polyacetylene

NASA Astrophysics Data System (ADS)

Stegmann, Thomas; Franco-Villafañe, John A.; Ortiz, Yenni P.; Kuhl, Ulrich; Mortessagne, Fabrice; Seligman, Thomas H.

2017-01-01

A novel approach to investigate the electron transport of cis- and trans-polyacetylene chains in the single-electron approximation is presented by using microwave emulation measurements and tight-binding calculations. In the emulation we take into account the different electronic couplings due to the double bonds leading to coupled dimer chains. The relative coupling constants are adjusted by DFT calculations. For sufficiently long chains a transport band gap is observed if the double bonds are present, whereas for identical couplings no band gap opens. The band gap can be observed also in relatively short chains, if additional edge atoms are absent, which cause strong resonance peaks within the band gap. The experimental results are in agreement with our tight-binding calculations using the nonequilibrium Green's function method. The tight-binding calculations show that it is crucial to include third nearest neighbor couplings to obtain the gap in the cis-polyacetylene.

Simulation, measurement, and emulation of photovoltaic modules using high frequency and high power density power electronic circuits

NASA Astrophysics Data System (ADS)

Erkaya, Yunus

The number of solar photovoltaic (PV) installations is growing exponentially, and to improve the energy yield and the efficiency of PV systems, it is necessary to have correct methods for simulation, measurement, and emulation. PV systems can be simulated using PV models for different configurations and technologies of PV modules. Additionally, different environmental conditions of solar irradiance, temperature, and partial shading can be incorporated in the model to accurately simulate PV systems for any given condition. The electrical measurement of PV systems both prior to and after making electrical connections is important for attaining high efficiency and reliability. Measuring PV modules using a current-voltage (I-V) curve tracer allows the installer to know whether the PV modules are 100% operational. The installed modules can be properly matched to maximize performance. Once installed, the whole system needs to be characterized similarly to detect mismatches, partial shading, or installation damage before energizing the system. This will prevent any reliability issues from the onset and ensure the system efficiency will remain high. A capacitive load is implemented in making I-V curve measurements with the goal of minimizing the curve tracer volume and cost. Additionally, the increase of measurement resolution and accuracy is possible via the use of accurate voltage and current measurement methods and accurate PV models to translate the curves to standard testing conditions. A move from mechanical relays to solid-state MOSFETs improved system reliability while significantly reducing device volume and costs. Finally, emulating PV modules is necessary for testing electrical components of a PV system. PV emulation simplifies and standardizes the tests allowing for different irradiance, temperature and partial shading levels to be easily tested. Proper emulation of PV modules requires an accurate and mathematically simple PV model that incorporates all known

Molecular characterization of putative Hepatozoon sp. from the sedge warbler (Acrocephalus schoenobaenus).

PubMed

Biedrzycka, Aleksandra; Kloch, Agnieszka; Migalska, Magdalena; Bielański, Wojciech

2013-05-01

We characterized partial sequences of 18S rDNA from sedge warblers infected with a parasite described previously as Hepatozoon kabeeni. Prevalence was 47% in sampled birds.We detected 3 parasite haplotypes in 62 sequenced samples from infected animals. In phylogenetic analyses, 2 of the putative Hepatozoon haplotypes closely resembled Lankesterella minima and L. valsainensis. The third haplotype grouped in a wider clade composed of Caryospora and Eimeria. None of the haplotypes showed resemblance to sequences of Hepatozoon from reptiles and mammals. Molecular detection results were consistent with those from microscopy of stained blood smears, confirming that the primers indeed amplified the parasite sequences. Here we provide evidence that the avian Hepatozoon-like parasites are most likely Lankesterella, supporting the suggestion that the systematic position of avian Hepatozoon-like species needs to be revised.

An evaluation and comparison of conservation guidelines for an at-risk migratory songbird

USGS Publications Warehouse

McNeil, Darin J.; Aldinger, Kyle R.; Bakermans, Marja H.; Lehman, Justin A.; Tisdale, Anna C.; Jones, John A.; Wood, Petra B.; Buehler, David A.; Smalling, Curtis G.; Siefferman, Lynn; Larkin, Jeffrey L.

2017-01-01

For at-risk wildlife species, it is important to consider conservation within the process of adaptive management. Golden-winged Warblers (Vermivora chrysoptera) are Neotropical migratory songbirds that are experiencing long-term population declines due in part to the loss of early-successional nesting habitat. Recently-developed Golden-winged Warbler habitat management guidelines are being implemented by USDA: Natural Resource Conservation Service (2014) and its partners through the Working Lands For Wildlife (WLFW) program. During 2012–2014, we studied the nesting ecology of Golden-winged Warblers in managed habitats of the eastern US that conformed to WLFW conservation practices. We evaluated five NRCS “management scenarios” with respect to nesting success and attainment of recommended nest site vegetation conditions outlined in the Golden-winged Warbler breeding habitat guidelines. Using estimates of territory density, pairing rate, nest survival, and clutch size, we also estimated fledgling productivity (number of fledglings/ha) for each management scenario. In general, Golden-winged Warbler nest survival declined as each breeding season advanced, but nest survival was similar across management scenarios. Within each management scenario, vegetation variables had little influence on nest survival. Still, percent Rubus cover and density of >2 m tall shrubs were relevant in some management scenarios. All five management scenarios rarely attained recommended levels of nest site vegetation conditions for Golden-winged, yet nest survival was high. Fledgling productivity estimates for each management scenario ranged from 2.1 to 8.6 fledglings/10 hectares. Our results indicate that targeted habitat management for Golden-winged Warblers using a variety of management techniques on private lands has the capability to yield high nest survival and fledgling productivity, and thus have the potential to contribute to the species recovery.

Simulation/Emulation Techniques: Compressing Schedules With Parallel (HW/SW) Development

NASA Technical Reports Server (NTRS)

Mangieri, Mark L.; Hoang, June

2014-01-01

NASA has always been in the business of balancing new technologies and techniques to achieve human space travel objectives. NASA's Kedalion engineering analysis lab has been validating and using many contemporary avionics HW/SW development and integration techniques, which represent new paradigms to NASA's heritage culture. Kedalion has validated many of the Orion HW/SW engineering techniques borrowed from the adjacent commercial aircraft avionics solution space, inserting new techniques and skills into the Multi - Purpose Crew Vehicle (MPCV) Orion program. Using contemporary agile techniques, Commercial-off-the-shelf (COTS) products, early rapid prototyping, in-house expertise and tools, and extensive use of simulators and emulators, NASA has achieved cost effective paradigms that are currently serving the Orion program effectively. Elements of long lead custom hardware on the Orion program have necessitated early use of simulators and emulators in advance of deliverable hardware to achieve parallel design and development on a compressed schedule.

Emulation of reactor irradiation damage using ion beams

DOE PAGES

Was, G. S.; Jiao, Z.; Getto, E.; ...

2014-06-14

The continued operation of existing light water nuclear reactors and the development of advanced nuclear reactor depend heavily on understanding how damage by radiation to levels degrades materials that serve as the structural components in reactor cores. The first high dose ion irradiation experiments on a ferritic-martensitic steel showing that ion irradiation closely emulates the full radiation damage microstructure created in-reactor are described. Ferritic-martensitic alloy HT9 (heat 84425) in the form of a hexagonal fuel bundle duct (ACO-3) accumulated 155 dpa at an average temperature of 443°C in the Fast Flux Test Facility (FFTF). Using invariance theory as a guide,more » irradiation of the same heat was conducted using self-ions (Fe++) at 5 MeV at a temperature of 460°C and to a dose of 188 displacements per atom. The void swelling was nearly identical between the two irradiation and the size and density of precipitates and loops following ion irradiation are within a factor of two of those for neutron irradiation. The level of agreement across all of the principal microstructure changes between ion and reactor irradiation establishes the capability of tailoring ion irradiation to emulate the reactor-irradiated microstructure.« less

Emulation of reionization simulations for Bayesian inference of astrophysics parameters using neural networks

NASA Astrophysics Data System (ADS)

Schmit, C. J.; Pritchard, J. R.

2018-03-01

Next generation radio experiments such as LOFAR, HERA, and SKA are expected to probe the Epoch of Reionization (EoR) and claim a first direct detection of the cosmic 21cm signal within the next decade. Data volumes will be enormous and can thus potentially revolutionize our understanding of the early Universe and galaxy formation. However, numerical modelling of the EoR can be prohibitively expensive for Bayesian parameter inference and how to optimally extract information from incoming data is currently unclear. Emulation techniques for fast model evaluations have recently been proposed as a way to bypass costly simulations. We consider the use of artificial neural networks as a blind emulation technique. We study the impact of training duration and training set size on the quality of the network prediction and the resulting best-fitting values of a parameter search. A direct comparison is drawn between our emulation technique and an equivalent analysis using 21CMMC. We find good predictive capabilities of our network using training sets of as low as 100 model evaluations, which is within the capabilities of fully numerical radiative transfer codes.

Continuous-variable quantum authentication of physical unclonable keys: Security against an emulation attack

NASA Astrophysics Data System (ADS)

Nikolopoulos, Georgios M.

2018-01-01

We consider a recently proposed entity authentication protocol in which a physical unclonable key is interrogated by random coherent states of light, and the quadratures of the scattered light are analyzed by means of a coarse-grained homodyne detection. We derive a sufficient condition for the protocol to be secure against an emulation attack in which an adversary knows the challenge-response properties of the key and moreover, he can access the challenges during the verification. The security analysis relies on Holevo's bound and Fano's inequality, and suggests that the protocol is secure against the emulation attack for a broad range of physical parameters that are within reach of today's technology.

User authentication based on the NFC host-card-emulation technology

NASA Astrophysics Data System (ADS)

Kološ, Jan; Kotyrba, Martin

2017-11-01

This paper deals with implementation of algorithms for data exchange between mobile devices supporting NFC HCE (Host-Card-Emulation) and a contactless NFC reader communicating in a read/write mode. This solution provides multiplatform architecture for data exchange between devices with a focus on safe and simple user authentication.

Application of a statistical emulator to fire emission modeling

Treesearch

Marwan Katurji; Jovanka Nikolic; Shiyuan Zhong; Scott Pratt; Lejiang Yu; Warren E. Heilman

2015-01-01

We have demonstrated the use of an advanced Gaussian-Process (GP) emulator to estimate wildland fire emissions over a wide range of fuel and atmospheric conditions. The Fire Emission Production Simulator, or FEPS, is used to produce an initial set of emissions data that correspond to some selected values in the domain of the input fuel and atmospheric parameters for...

The application of emulation techniques in the analysis of highly reliable, guidance and control computer systems

NASA Technical Reports Server (NTRS)

Migneault, Gerard E.

1987-01-01

Emulation techniques can be a solution to a difficulty that arises in the analysis of the reliability of guidance and control computer systems for future commercial aircraft. Described here is the difficulty, the lack of credibility of reliability estimates obtained by analytical modeling techniques. The difficulty is an unavoidable consequence of the following: (1) a reliability requirement so demanding as to make system evaluation by use testing infeasible; (2) a complex system design technique, fault tolerance; (3) system reliability dominated by errors due to flaws in the system definition; and (4) elaborate analytical modeling techniques whose precision outputs are quite sensitive to errors of approximation in their input data. Use of emulation techniques for pseudo-testing systems to evaluate bounds on the parameter values needed for the analytical techniques is then discussed. Finally several examples of the application of emulation techniques are described.

An inexpensive method for quantifying incubation patterns of open-cup nesting birds, with data for black-throated Blue warblers

USGS Publications Warehouse

Joyce, Elizabeth M.; Sillett, T. Scott; Holmes, Richard T.

2001-01-01

Quantifying incubation patterns has often involved long observation periods in the field, video cameras, or the use of other electronic devices that sometimes require the partial destruction of clutches and insertion of artificial eggs. In this study, we used an inexpensive, nondestructive method involving temperature probes combined with data loggers to examine the incubation rhythm of female Black-throated Blue Warblers (Dendroica caerulescens). The method provided detailed records of on–off patterns for females for selected 24-h periods during incubation. Female warblers spent an average (±SE) of 64.0% of daylight hours incubating in bouts lasting 20.5 ± 1.5 min and made 2.4 ± 0.1 departures from the nest/h on trips that lasted 10.6 ± 0.7 min. Incubation bouts were longer and females spent more time incubating per hour in the mornings and late afternoons than at mid-day. Older females had longer incubation bouts and tended to have shorter incubation periods than did yearling females, suggesting that experienced individuals were more effective incubators. Because of its ease of use and because nests with probes were not depredated at a higher rate than controls, we suggest that the temperature probe/data logger method is an efficient and effective way to quantify incubation rhythms for open-cup nesting birds.

Research and emulation of ranging in BPON system

NASA Astrophysics Data System (ADS)

Yang, Guangxiang; Tao, Dexin; He, Yan

2005-12-01

Ranging is one of the key technologies in Broadband Passive Optical Network based on the ATM (BPON) system. It is complex for software designers and difficult to test. In order to simplify the ranging procedure, enhance its efficiency, and find an appropriate method to verify it, a new ranging procedure that completely satisfies the requirements specified in ITU-T G.983.1 and one verifying method is proposed in this paper. A kind of ranging procedure without serial number (SN) searching function, called one-by-one ranging are developed under the condition of cold PON, cold Optical Network Termination (ONU). The ranging procedure includes the use of OLT and ONU flow charts respectively. By using the network emulation software OPNET, the BPON system is modeled and the ranging procedure is simulated. The emulation experimental results show that the presented ranging procedure can effectively eliminate the collision of burst mode signals between ONUs, which can be ranged one-by-one under the controlling of OLT, while also enhancing the ranging efficiency. As all of the message formats used in this research conform with the ITU-T G.983.1, the ranging procedure can meet the protocol specifications with good interoperability, and is very compatible with products of other manufacturer. According to the present study of ranging procedures, guidelines and principles are provided, Also some design difficulties are eliminated in the software design.

Connecting the Brain to Itself through an Emulation

PubMed Central

Serruya, Mijail D.

2017-01-01

Pilot clinical trials of human patients implanted with devices that can chronically record and stimulate ensembles of hundreds to thousands of individual neurons offer the possibility of expanding the substrate of cognition. Parallel trains of firing rate activity can be delivered in real-time to an array of intermediate external modules that in turn can trigger parallel trains of stimulation back into the brain. These modules may be built in software, VLSI firmware, or biological tissue as in vitro culture preparations or in vivo ectopic construct organoids. Arrays of modules can be constructed as early stage whole brain emulators, following canonical intra- and inter-regional circuits. By using machine learning algorithms and classic tasks known to activate quasi-orthogonal functional connectivity patterns, bedside testing can rapidly identify ensemble tuning properties and in turn cycle through a sequence of external module architectures to explore which can causatively alter perception and behavior. Whole brain emulation both (1) serves to augment human neural function, compensating for disease and injury as an auxiliary parallel system, and (2) has its independent operation bootstrapped by a human-in-the-loop to identify optimal micro- and macro-architectures, update synaptic weights, and entrain behaviors. In this manner, closed-loop brain-computer interface pilot clinical trials can advance strong artificial intelligence development and forge new therapies to restore independence in children and adults with neurological conditions. PMID:28713235

Emulation Platform for Cyber Analysis of Wireless Communication Network Protocols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Leeuwen, Brian P.; Eldridge, John M.

Wireless networking and mobile communications is increasing around the world and in all sectors of our lives. With increasing use, the density and complexity of the systems increase with more base stations and advanced protocols to enable higher data throughputs. The security of data transported over wireless networks must also evolve with the advances in technologies enabling more capable wireless networks. However, means for analysis of the effectiveness of security approaches and implementations used on wireless networks are lacking. More specifically a capability to analyze the lower-layer protocols (i.e., Link and Physical layers) is a major challenge. An analysis approachmore » that incorporates protocol implementations without the need for RF emissions is necessary. In this research paper several emulation tools and custom extensions that enable an analysis platform to perform cyber security analysis of lower layer wireless networks is presented. A use case of a published exploit in the 802.11 (i.e., WiFi) protocol family is provided to demonstrate the effectiveness of the described emulation platform.« less

UPEML Version 2. 0: A machine-portable CDC Update emulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehlhorn, T.A.; Young, M.F.

1987-05-01

UPEML is a machine-portable CDC Update emulation program. UPEML is written in ANSI standard Fortran-77 and is relatively simple and compact. It is capable of emulating a significant subset of the standard CDC Update functions, including program library creation and subsequent modification. Machine-portability is an essential attribute of UPEML. UPEML was written primarily to facilitate the use of CDC-based scientific packages on alternate computer systems such as the VAX 11/780 and the IBM 3081. UPEML has also been successfully used on the multiprocessor ELXSI, on CRAYs under both COS and CTSS operating systems, on APOLLO workstations, and on the HP-9000.more » Version 2.0 includes enhanced error checking, full ASCI character support, a program library audit capability, and a partial update option in which only selected or modified decks are written to the compile file. Further enhancements include checks for overlapping corrections, processing of nested calls to common decks, and reads and addfiles from alternate input files.« less

Primary peak and chronic malaria infection levels are correlated in experimentally infected great reed warblers.

PubMed

Asghar, Muhammad; Westerdahl, Helena; Zehtindjiev, Pavel; Ilieva, Mihaela; Hasselquist, Dennis; Bensch, Staffan

2012-09-01

Malaria parasites often manage to maintain an infection for several months or years in their vertebrate hosts. In humans, rodents and birds, most of the fitness costs associated with malaria infections are in the short initial primary (high parasitaemia) phase of the infection, whereas the chronic phase (low parasitaemia) is more benign to the host. In wild birds, malaria parasites have mainly been studied during the chronic phase of the infection. This is because the initial primary phase of infection is short in duration and infected birds with severe disease symptoms tend to hide in sheltered places and are thus rarely caught and sampled. We therefore wanted to investigate the relationship between the parasitaemia during the primary and chronic phases of the infection using an experimental infection approach. We found a significant positive correlation between parasitaemia in the primary peak and the subsequent chronic phase of infection when we experimentally infected great reed warblers (Acrocephalus arundinaceus) with Plasmodium ashfordi. The reason for this association remains to be understood, but might arise from individual variation in exoerythrocytic parasite reservoirs in hosts, parasite antigenic diversity and/or host genetics. Our results suggest that the chronic phase parasitaemia can be used to qualitatively infer the parasitaemia of the preceding and more severe primary phase, which is a very important finding for studies of avian malaria in wild populations.

Developing management guidelines for cerulean warbler breeding habitat

Treesearch

Paul B. Hamel; Kenneth V. Rosenberg

2007-01-01

Recovery activities for species of conservation concern may be directed to acquire and protect habitats known to contain the species, or to produce suitable habitats or locations suspected to be capable of supporting populations of the species. Management of those habitats ultimately becomes necessary, especially where production of additional habitats is deemed...

Diet preferences of goats in a subtropical dry forest and implications for habitat management

Treesearch

Genie M. Fleming; Joseph Wunderle Jr.; David N. Ewert

2016-01-01

As part of an experimental study of using controlled goat grazing to manage winter habitat of the Kirtland’s warbler (Setophaga kirtlandii), an endangered Nearctic neotropical migratory bird, we evaluated diet preferences of domesticated goats within early successional subtropical dry forest in The Bahamas. We expected goats would show a low preference for two plants (...

Statistical Emulation of Climate Model Projections Based on Precomputed GCM Runs*

DOE PAGES

Castruccio, Stefano; McInerney, David J.; Stein, Michael L.; ...

2014-02-24

The authors describe a new approach for emulating the output of a fully coupled climate model under arbitrary forcing scenarios that is based on a small set of precomputed runs from the model. Temperature and precipitation are expressed as simple functions of the past trajectory of atmospheric CO 2 concentrations, and a statistical model is fit using a limited set of training runs. The approach is demonstrated to be a useful and computationally efficient alternative to pattern scaling and captures the nonlinear evolution of spatial patterns of climate anomalies inherent in transient climates. The approach does as well as patternmore » scaling in all circumstances and substantially better in many; it is not computationally demanding; and, once the statistical model is fit, it produces emulated climate output effectively instantaneously. In conclusion, it may therefore find wide application in climate impacts assessments and other policy analyses requiring rapid climate projections.« less

Using Texas Instruments Emulators as Teaching Tools in Quantitative Chemical Analysis

ERIC Educational Resources Information Center

Young, Vaneica Y.

2011-01-01

This technology report alerts upper-division undergraduate chemistry faculty and lecturers to the use of Texas Instruments emulators as virtual graphing calculators. These may be used in multimedia lectures to instruct students on the use of their graphing calculators to obtain solutions to complex chemical problems. (Contains 1 figure.)

A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations

DTIC Science & Technology

2017-09-01

AWARD NUMBER: W81XWH-16-1-0569 TITLE: A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members...Headquarters Services , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202- 4302...GRANT NUMBER A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations 5c

Fast and Precise Emulation of Stochastic Biochemical Reaction Networks With Amplified Thermal Noise in Silicon Chips.

PubMed

Kim, Jaewook; Woo, Sung Sik; Sarpeshkar, Rahul

2018-04-01

The analysis and simulation of complex interacting biochemical reaction pathways in cells is important in all of systems biology and medicine. Yet, the dynamics of even a modest number of noisy or stochastic coupled biochemical reactions is extremely time consuming to simulate. In large part, this is because of the expensive cost of random number and Poisson process generation and the presence of stiff, coupled, nonlinear differential equations. Here, we demonstrate that we can amplify inherent thermal noise in chips to emulate randomness physically, thus alleviating these costs significantly. Concurrently, molecular flux in thermodynamic biochemical reactions maps to thermodynamic electronic current in a transistor such that stiff nonlinear biochemical differential equations are emulated exactly in compact, digitally programmable, highly parallel analog "cytomorphic" transistor circuits. For even small-scale systems involving just 80 stochastic reactions, our 0.35-μm BiCMOS chips yield a 311× speedup in the simulation time of Gillespie's stochastic algorithm over COPASI, a fast biochemical-reaction software simulator that is widely used in computational biology; they yield a 15 500× speedup over equivalent MATLAB stochastic simulations. The chip emulation results are consistent with these software simulations over a large range of signal-to-noise ratios. Most importantly, our physical emulation of Poisson chemical dynamics does not involve any inherently sequential processes and updates such that, unlike prior exact simulation approaches, they are parallelizable, asynchronous, and enable even more speedup for larger-size networks.

Annual variation in foraging ecology of prothonotary warblers during the breeding season

USGS Publications Warehouse

Petit, L.J.; Petit, D.R.; Petit, K.E.; Fleming, W.J.

1990-01-01

We studied foraging ecology of Prothonotary Warblers (Protonotaria citrea) along the Tennessee River in west-central Tennessee during the breeding seasons of 1984-1987. We analyzed seven foraging variables to determine if this population exhibited annual variation in foraging behavior. Based on nearly 3,000 foraging maneuvers, most variables showed significant interyear variation during the four prenestling and three nestling periods we studied. This interyear variation probably was due -to proximate, environmental cues--such as distribution and abundance of arthropods - which, in turn, were influenced by local weather conditions. Researchers should consider the consequences of combining foraging behavior data collected in different years, because resolution of ecological trends may be sacrificed by considering only general patterns of foraging ecology and not the dynamics of those activities. In addition, because of annual variability, foraging data collected in only one year, regardless of the number of observations gathered, may not provide an accurate concept of the foraging ecology in insectivorous birds.

The Outline of Personhood Law Regarding Artificial Intelligences and Emulated Human Entities

NASA Astrophysics Data System (ADS)

Muzyka, Kamil

2013-12-01

On the verge of technological breakthroughs, which define and revolutionize our understanding of intelligence, cognition, and personhood, especially when speaking of artificial intelligences and mind uploads, one must consider the legal implications of granting personhood rights to artificial intelligences or emulated human entities

Using Nocturnal Flight Calls to Assess the Fall Migration of Warblers and Sparrows along a Coastal Ecological Barrier

PubMed Central

Smith, Adam D.; Paton, Peter W. C.; McWilliams, Scott R.

2014-01-01

Atmospheric conditions fundamentally influence the timing, intensity, energetics, and geography of avian migration. While radar is typically used to infer the influence of weather on the magnitude and spatiotemporal patterns of nocturnal bird migration, monitoring the flight calls produced by many bird species during nocturnal migration represents an alternative methodology and provides information regarding the species composition of nocturnal migration. We used nocturnal flight call (NFC) recordings of at least 22 migratory songbirds (14 warbler and 8 sparrow species) during fall migration from eight sites along the mainland and island coasts of Rhode Island to evaluate five hypotheses regarding NFC detections. Patterns of warbler and sparrow NFC detections largely supported our expectations in that (1) NFC detections associated positively and strongly with wind conditions that influence the intensity of coastal bird migration and negatively with regional precipitation; (2) NFCs increased during conditions with reduced visibility (e.g., high cloud cover); (3) NFCs decreased with higher wind speeds, presumably due mostly to increased ambient noise; and (4) coastal mainland sites recorded five to nine times more NFCs, on average, than coastal nearshore or offshore island sites. However, we found little evidence that (5) nightly or intra-night patterns of NFCs reflected the well-documented latitudinal patterns of migrant abundance on an offshore island. Despite some potential complications in inferring migration intensity and species composition from NFC data, the acoustic monitoring of NFCs provides a viable and complementary methodology for exploring the spatiotemporal patterns of songbird migration as well as evaluating the atmospheric conditions that shape these patterns. PMID:24643060

Sex-specific associative learning cues and inclusive fitness benefits in the Seychelles warbler.

PubMed

Richardson, D S; Burke, T; Komdeurs, J

2003-09-01

In cooperative breeding vertebrates, indirect fitness benefits would be maximized by subordinates that accurately assess their relatedness to group offspring and preferentially help more closely related kin. In the Seychelles warbler (Acrocephalus sechellensis), we found a positive relationship between subordinate-nestling kinship (determined using microsatellite marker genotypes) and provisioning rates, but only for female subordinates. Female subordinates that helped were significantly more related to the nestlings than were nonhelpers, and the decision to help appears to be based on associative learning cues. High levels of female infidelity means that subordinates cannot trust their legitimacy through the male line, consequently they appear to use the continued presence of the primary female, but not the primary male, as a reliable cue to determine when to feed nestlings. By using effective discrimination, female subordinates are able to maximize the indirect benefits gained within a cooperative breeding system otherwise driven primarily by direct breeding benefits.

[Book review] Massachusetts breeding bird atlas

USGS Publications Warehouse

Robbins, Chandler S.

2005-01-01

A glance at the dust jacket of this handsome volume drives home the conservation message that breeding bird atlases are designed to promote—that bird populations are changing over vast areas and, unless we become aware of changes in status and take remedial action, some species will disappear from our neighborhoods and even our county or state. A case in point involves the closely related Golden-winged Warbler (Vermivora chrysoptera) and Blue- winged Warbler (Vermivora pinus). The males are shown in the atlas with their breeding distribution maps. When I was an active birder in the Boston suburbs in the 1930s, the Golden-winged Warbler was a common breeder and it was a treat to find a Blue-winged Warbler. The atlas map 40 years later (1974–1979) shows only five confirmed records statewide for the Golden-winged Warbler, compared with 73 for the Blue-winged Warbler, and the Golden-winged Warbler is now listed as endangered by the Massachusetts Division of Fisheries and Wildlife. Nationally, it is a species of management concern.

Wapiti and warblers: integrating game and nongame management in Idaho

Treesearch

C. R. Groves; J. W. Unsworth

1993-01-01

The primary concern of wildlife managers in the USDA Forest Service (USFS) and ldaho Department of Fish and Game (IDFG) is maintaining elk herds and quality elk hunting. As a result, nongame species like neotropical migratory landbirds do not receive much management attention. Cause for concern over this neglect are twofold: 1) forest fragmentation may be having...

A device for emulating cuff recordings of action potentials propagating along peripheral nerves.

PubMed

Rieger, Robert; Schuettler, Martin; Chuang, Sheng-Chih

2014-09-01

This paper describes a device that emulates propagation of action potentials along a peripheral nerve, suitable for reproducible testing of bio-potential recording systems using nerve cuff electrodes. The system is a microcontroller-based stand-alone instrument which uses established nerve and electrode models to represent neural activity of real nerves recorded with a nerve cuff interface, taking into consideration electrode impedance, voltages picked up by the electrodes, and action potential propagation characteristics. The system emulates different scenarios including compound action potentials with selectable propagation velocities and naturally occurring nerve traffic from different velocity fiber populations. Measured results from a prototype implementation are reported and compared with in vitro recordings from Xenopus Laevis frog sciatic nerve, demonstrating that the electrophysiological setting is represented to a satisfactory degree, useful for the development, optimization and characterization of future recording systems.

MCCx C3I Control Center Interface Emulator

NASA Technical Reports Server (NTRS)

Mireles, James R.

2010-01-01

This slide presentation reviews the project to develop and demonstrate alternate Information Technologies and systems for new Mission Control Centers that will reduce the cost of facility development, maintenance and operational costs and will enable more efficient cost and effective operations concepts for ground support operations. The development of a emulator for the Control Center capability will enable the facilities to conduct the simulation requiring interactivity with the Control Center when it is off line or unavailable, and it will support testing of C3I interfaces for both command and telemetry data exchange messages (DEMs).

Evaluating the accuracy of climate change pattern emulation for low warming targets

NASA Astrophysics Data System (ADS)

Tebaldi, Claudia; Knutti, Reto

2018-05-01

Global climate policy is increasingly debating the value of very low warming targets, yet not many experiments conducted with global climate models in their fully coupled versions are currently available to help inform studies of the corresponding impacts. This raises the question whether a map of warming or precipitation change in a world 1.5 °C warmer than preindustrial can be emulated from existing simulations that reach higher warming targets, or whether entirely new simulations are required. Here we show that also for this type of low warming in strong mitigation scenarios, climate change signals are quite linear as a function of global temperature. Therefore, emulation techniques amounting to linear rescaling on the basis of global temperature change ratios (like simple pattern scaling) provide a viable way forward. The errors introduced are small relative to the spread in the forced response to a given scenario that we can assess from a multi-model ensemble. They are also small relative to the noise introduced into the estimates of the forced response by internal variability within a single model, which we can assess from either control simulations or initial condition ensembles. Challenges arise when scaling inadvertently reduces the inter-model spread or suppresses the internal variability, both important sources of uncertainty for impact assessment, or when the scenarios have very different characteristics in the composition of the forcings. Taking advantage of an available suite of coupled model simulations under low-warming and intermediate scenarios, we evaluate the accuracy of these emulation techniques and show that they are unlikely to represent a substantial contribution to the total uncertainty.

Emulating Simulations of Cosmic Dawn for 21 cm Power Spectrum Constraints on Cosmology, Reionization, and X-Ray Heating

NASA Astrophysics Data System (ADS)

Kern, Nicholas S.; Liu, Adrian; Parsons, Aaron R.; Mesinger, Andrei; Greig, Bradley

2017-10-01

Current and upcoming radio interferometric experiments are aiming to make a statistical characterization of the high-redshift 21 cm fluctuation signal spanning the hydrogen reionization and X-ray heating epochs of the universe. However, connecting 21 cm statistics to the underlying physical parameters is complicated by the theoretical challenge of modeling the relevant physics at computational speeds quick enough to enable exploration of the high-dimensional and weakly constrained parameter space. In this work, we use machine learning algorithms to build a fast emulator that can accurately mimic an expensive simulation of the 21 cm signal across a wide parameter space. We embed our emulator within a Markov Chain Monte Carlo framework in order to perform Bayesian parameter constraints over a large number of model parameters, including those that govern the Epoch of Reionization, the Epoch of X-ray Heating, and cosmology. As a worked example, we use our emulator to present an updated parameter constraint forecast for the Hydrogen Epoch of Reionization Array experiment, showing that its characterization of a fiducial 21 cm power spectrum will considerably narrow the allowed parameter space of reionization and heating parameters, and could help strengthen Planck's constraints on {σ }8. We provide both our generalized emulator code and its implementation specifically for 21 cm parameter constraints as publicly available software.

Neural Network Emulation of Reionization Simulations

NASA Astrophysics Data System (ADS)

Schmit, Claude J.; Pritchard, Jonathan R.

2018-05-01

Next generation radio experiments such as LOFAR, HERA and SKA are expected to probe the Epoch of Reionization and claim a first direct detection of the cosmic 21cm signal within the next decade. One of the major challenges for these experiments will be dealing with enormous incoming data volumes. Machine learning is key to increasing our data analysis efficiency. We consider the use of an artificial neural network to emulate 21cmFAST simulations and use it in a Bayesian parameter inference study. We then compare the network predictions to a direct evaluation of the EoR simulations and analyse the dependence of the results on the training set size. We find that the use of a training set of size 100 samples can recover the error contours of a full scale MCMC analysis which evaluates the model at each step.

ProtocolNavigator: emulation-based software for the design, documentation and reproduction biological experiments.

PubMed

Khan, Imtiaz A; Fraser, Adam; Bray, Mark-Anthony; Smith, Paul J; White, Nick S; Carpenter, Anne E; Errington, Rachel J

2014-12-01

Experimental reproducibility is fundamental to the progress of science. Irreproducible research decreases the efficiency of basic biological research and drug discovery and impedes experimental data reuse. A major contributing factor to irreproducibility is difficulty in interpreting complex experimental methodologies and designs from written text and in assessing variations among different experiments. Current bioinformatics initiatives either are focused on computational research reproducibility (i.e. data analysis) or laboratory information management systems. Here, we present a software tool, ProtocolNavigator, which addresses the largely overlooked challenges of interpretation and assessment. It provides a biologist-friendly open-source emulation-based tool for designing, documenting and reproducing biological experiments. ProtocolNavigator was implemented in Python 2.7, using the wx module to build the graphical user interface. It is a platform-independent software and freely available from http://protocolnavigator.org/index.html under the GPL v2 license. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Territory choice during the breeding tenure of male sedge warblers.

PubMed

Zając, Tadeusz; Bielański, Wojciech; Solarz, Wojciech

2011-12-01

A territorial male can shift the location of its territory from year to year in order to increase its quality. The male can base its decision on environmental cues or else on its breeding experiences (when territory shift is caused by breeding failure in previous seasons). We tested these possible mechanisms of territory choice in the sedge warbler (Acrocephalus schoenobaenus), a territorial migrating passerine that occupies wetlands. This species bases its territory choices on an environmental cue: tall wetland vegetation cover. We found that the magnitude of territory quality improvement between seasons (measured as the area of tall wetland vegetation) increased throughout the early stages of a male's breeding career as a result of territory shifts dependent on the earliness of arrival. The distance the territory was shifted between seasons depended negatively on the previous year's territory quality and, less clearly, on the previous year's mating success. On the other hand, previous mating or nesting success had no influence on territory quality improvement between seasons as measured in terms of vegetation. The results imply that tall wetland vegetation is a long-term, effective environmental cue and that a preference for territories in which this type of landcover prevails has evolved into a rigid behavioral mechanism, supplemented by short-term individual experiences of breeding failure.

Age-specific haemosporidian infection dynamics and survival in Seychelles warblers

PubMed Central

Hammers, Martijn; Komdeur, Jan; Kingma, Sjouke A.; Hutchings, Kimberly; Fairfield, Eleanor A.; Gilroy, Danielle L.; Richardson, David S.

2016-01-01

Parasites may severely impact the fitness and life-history of their hosts. After infection, surviving individuals may suppress the growth of the parasite, or completely clear the infection and develop immunity. Consequently, parasite prevalence is predicted to decline with age. Among elderly individuals, immunosenescence may lead to a late-life increase in infection prevalence. We used a 21-year longitudinal dataset from one population of individually-marked Seychelles warblers (Acrocephalus sechellensis) to investigate age-dependent prevalence of the GRW1 strain of the intracellular protozoan blood parasite Haemoproteus nucleocondensus and whether infections with this parasite affect age-dependent survival. We analyzed 2454 samples from 1431 individuals and found that H. nucleocondensus infections could rarely be detected in nestlings. Prevalence increased strongly among fledglings and peaked among older first year birds. Prevalence was high among younger adults and declined steeply until ca 4 years of age, after which it was stable. Contrary to expectations, H. nucleocondensus prevalence did not increase among elderly individuals and we found no evidence that annual survival was lower in individuals suffering from an infection. Our results suggest that individuals clear or suppress infections and acquire immunity against future infections, and provide no evidence for immunosenescence nor an impact of chronic infections on survival. PMID:27431430

Emulation and design of terahertz reflection-mode confocal scanning microscopy based on virtual pinhole

NASA Astrophysics Data System (ADS)

Yang, Yong-fa; Li, Qi

2014-12-01

In the practical application of terahertz reflection-mode confocal scanning microscopy, the size of detector pinhole is an important factor that determines the performance of spatial resolution characteristic of the microscopic system. However, the use of physical pinhole brings some inconvenience to the experiment and the adjustment error has a great influence on the experiment result. Through reasonably selecting the parameter of matrix detector virtual pinhole (VPH), it can efficiently approximate the physical pinhole. By using this approach, the difficulty of experimental calibration is reduced significantly. In this article, an imaging scheme of terahertz reflection-mode confocal scanning microscopy that is based on the matrix detector VPH is put forward. The influence of detector pinhole size on the axial resolution of confocal scanning microscopy is emulated and analyzed. Then, the parameter of VPH is emulated when the best axial imaging performance is reached.

Spatio-temporal variation in territory quality and oxidative status: a natural experiment in the Seychelles warbler (Acrocephalus sechellensis).

PubMed

van de Crommenacker, Janske; Komdeur, Jan; Burke, Terry; Richardson, David S

2011-05-01

1. Fluctuations in the quality of the habitat in which an animal lives can have major consequences for its behaviour and physiological state. In poor-quality habitat with low food availability, metabolically intensive foraging activity is likely to result in increased generation of reactive oxygen species, while scarcity of food can lead to a weakening of exogenously derived antioxidant defences. The consequent oxidant/antioxidant imbalance may lead to elevated oxidative stress. 2. Although the link between food availability and oxidative stress has been studied in the laboratory, very little is known about this relationship in the wild. Here, we investigate the association between territory quality (measured through food availability) and oxidative stress in the Seychelles warbler (Acrocephalus sechellensis). 3. Seychelles warblers are insectivorous birds that inhabit a fixed feeding territory year round. Individuals experience profound and rapid local fluctuations in territory quality within these territories, owing to changing patterns of vegetation defoliation resulting from seasonal changes in prevailing wind direction and wind-borne salt spray. 4. As expected, oxidant generation (measured as reactive oxygen metabolites; ROMs) was higher when territory quality was low, but there was no correlation between territory quality and antioxidant capacity (OXY). The negative correlation between territory quality and ROMs was significant between individuals and approached significance within individuals, indicating that the pattern resulted from individual responses to environmental variation. 5. ROMs and OXY levels within individuals were positively correlated, but the relationship between territory quality and ROMs persisted after including OXY as a covariate, implying that oxidative stress occurs in low territory quality conditions. 6. Our results indicate that the oxidative stress balance of an individual is sensitive to relatively short-term changes in territory

Spatio-temporal variation in territory quality and oxidative status: a natural experiment in the Seychelles warbler (Acrocephalus sechellensis)

PubMed Central

van de Crommenacker, Janske; Komdeur, Jan; Burke, Terry; Richardson, David S

2011-01-01

1.Fluctuations in the quality of the habitat in which an animal lives can have major consequences for its behaviour and physiological state. In poor-quality habitat with low food availability, metabolically intensive foraging activity is likely to result in increased generation of reactive oxygen species, while scarcity of food can lead to a weakening of exogenously derived antioxidant defences. The consequent oxidant/antioxidant imbalance may lead to elevated oxidative stress. 2.Although the link between food availability and oxidative stress has been studied in the laboratory, very little is known about this relationship in the wild. Here, we investigate the association between territory quality (measured through food availability) and oxidative stress in the Seychelles warbler (Acrocephalus sechellensis). 3.Seychelles warblers are insectivorous birds that inhabit a fixed feeding territory year round. Individuals experience profound and rapid local fluctuations in territory quality within these territories, owing to changing patterns of vegetation defoliation resulting from seasonal changes in prevailing wind direction and wind-borne salt spray. 4.As expected, oxidant generation (measured as reactive oxygen metabolites; ROMs) was higher when territory quality was low, but there was no correlation between territory quality and antioxidant capacity (OXY). The negative correlation between territory quality and ROMs was significant between individuals and approached significance within individuals, indicating that the pattern resulted from individual responses to environmental variation. 5.ROMs and OXY levels within individuals were positively correlated, but the relationship between territory quality and ROMs persisted after including OXY as a covariate, implying that oxidative stress occurs in low territory quality conditions. 6.Our results indicate that the oxidative stress balance of an individual is sensitive to relatively short-term changes in territory quality

The use of perturbed physics ensembles and emulation in palaeoclimate reconstruction (Invited)

NASA Astrophysics Data System (ADS)

Edwards, T. L.; Rougier, J.; Collins, M.

2010-12-01

Climate is a coherent process, with correlations and dependencies across space, time, and climate variables. However, reconstructions of palaeoclimate traditionally consider individual pieces of information independently, rather than making use of this covariance structure. Such reconstructions are at risk of being unphysical or at least implausible. Climate simulators such as General Circulation Models (GCMs), on the other hand, contain climate system theory in the form of dynamical equations describing physical processes, but are imperfect and computationally expensive. These two datasets - pointwise palaeoclimate reconstructions and climate simulator evaluations - contain complementary information, and a statistical synthesis can produce a palaeoclimate reconstruction that combines them while not ignoring their limitations. We use an ensemble of simulators with perturbed parameterisations, to capture the uncertainty about the simulator variant, and our method also accounts for structural uncertainty. The resulting reconstruction contains a full expression of climate uncertainty, not just pointwise but also jointly over locations. Such joint information is crucial in determining spatially extensive features such as isotherms, or the location of the tree-line. A second outcome of the statistical analysis is a refined distribution for the simulator parameters. In this way, information from palaeoclimate observations can be used directly in quantifying uncertainty in future climate projections. The main challenge is the expense of running a large scale climate simulator: each evaluation of an atmosphere-ocean GCM takes several months of computing time. The solution is to interpret the ensemble of evaluations within an 'emulator', which is a statistical model of the simulator. This technique has been used fruitfully in the statistical field of Computer Models for two decades, and has recently been applied in estimating uncertainty in future climate predictions in the

On the diagnostic emulation technique and its use in the AIRLAB

NASA Technical Reports Server (NTRS)

Migneault, Gerard E.

1988-01-01

An aid is presented for understanding and judging the relevance of the diagnostic emulation technique to studies of highly reliable, digital computing systems for aircraft. A short review is presented of the need for and the use of the technique as well as an explanation of its principles of operation and implementation. Details that would be needed for operational control or modification of existing versions of the technique are not described.

Real time wind farm emulation using SimWindFarm toolbox

NASA Astrophysics Data System (ADS)

Topor, Marcel

2016-06-01

This paper presents a wind farm emulation solution using an open source Matlab/Simulink toolbox and the National Instruments cRIO platform. This work is based on the Aeolus SimWindFarm (SWF) toolbox models developed at Aalborg university, Denmark. Using the Matlab Simulink models developed in SWF, the modeling code can be exported to a real time model using the NI Veristand model framework and the resulting code is integrated as a hardware in the loop control on the NI 9068 platform.

A Burning Rate Emulator (BRE) for Study in Microgravity

NASA Technical Reports Server (NTRS)

Markan, A.; Sunderland, P. B.; Quintiere, J. G.; DeRis, J.; Stocker, D. P.

2015-01-01

A gas-fueled burner, the Burning Rate Emulator (BRE), is used to emulate condensed-phase fuel flames. The design has been validated to easily measure the burning behavior of condensed-phase fuels by igniting a controlled stream of gas fuel and diluent. Four properties, including the heat of combustion, the heat of gasification, the surface temperature, and the laminar smoke point, are assumed to be sufficient to define the steady burning rate of a condensed-phase fuel. The heat of gasification of the fuel is determined by measuring the heat flux and the fuel flow rate. Microgravity BRE tests in the NASA 5.2 s drop facility have examined the burning of pure methane and ethylene (pure and 50 in N2 balance). Fuel flow rates, chamber oxygen concentration and initial pressure have been varied. Two burner sizes, 25 and 50 mm respectively, are chosen to examine the nature of initial microgravity burning. The tests reveal bubble-like flames that increase within the 5.2s drop but the heat flux received from the flame appears to asymptotically approach steady state. Portions of the methane flames appear to locally detach and extinguish at center, while its shape remains fixed, but growing. The effective heat of gasification is computed from the final measured net heat flux and the fuel flow rate under the assumption of an achieved steady burning. Heat flux (or mass flux) and flame position are compared with stagnant layer burning theory. The analysis offers the prospect of more complete findings from future longer duration ISS experiments.

Emulation of the MBM-MEDUSA model: exploring the sea level and the basin-to-shelf transfer influence on the system dynamics

NASA Astrophysics Data System (ADS)

Ermakov, Ilya; Crucifix, Michel; Munhoven, Guy

2013-04-01

Complex climate models require high computational burden. However, computational limitations may be avoided by using emulators. In this work we present several approaches for dynamical emulation (also called metamodelling) of the Multi-Box Model (MBM) coupled to the Model of Early Diagenesis in the Upper Sediment A (MEDUSA) that simulates the carbon cycle of the ocean and atmosphere [1]. We consider two experiments performed on the MBM-MEDUSA that explore the Basin-to-Shelf Transfer (BST) dynamics. In both experiments the sea level is varied according to a paleo sea level reconstruction. Such experiments are interesting because the BST is an important cause of the CO2 variation and the dynamics is potentially nonlinear. The output that we are interested in is the variation of the carbon dioxide partial pressure in the atmosphere over the Pleistocene. The first experiment considers that the BST is fixed constant during the simulation. In the second experiment the BST is interactively adjusted according to the sea level, since the sea level is the primary control of the growth and decay of coral reefs and other shelf carbon reservoirs. The main aim of the present contribution is to create a metamodel of the MBM-MEDUSA using the Dynamic Emulation Modelling methodology [2] and compare the results obtained using linear and non-linear methods. The first step in the emulation methodology used in this work is to identify the structure of the metamodel. In order to select an optimal approach for emulation we compare the results of identification obtained by the simple linear and more complex nonlinear models. In order to identify the metamodel in the first experiment the simple linear regression and the least-squares method is sufficient to obtain a 99,9% fit between the temporal outputs of the model and the metamodel. For the second experiment the MBM's output is highly nonlinear. In this case we apply nonlinear models, such as, NARX, Hammerstein model, and an 'ad

BSM (+BMM) Data Emulator Dynamic Interrogative Data Capture (DIDC) Assessment Report: Proof of Concept

DOT National Transportation Integrated Search

2016-04-01

The report documents the study conducted as part of the BSM+BMM Data Emulator project, to examine the DIDC concept and determine the best set of DIDC parameters that provide the most support to the performance measure estimation process with the leas...

A learning-based autonomous driver: emulate human driver's intelligence in low-speed car following

NASA Astrophysics Data System (ADS)

Wei, Junqing; Dolan, John M.; Litkouhi, Bakhtiar

2010-04-01

In this paper, an offline learning mechanism based on the genetic algorithm is proposed for autonomous vehicles to emulate human driver behaviors. The autonomous driving ability is implemented based on a Prediction- and Cost function-Based algorithm (PCB). PCB is designed to emulate a human driver's decision process, which is modeled as traffic scenario prediction and evaluation. This paper focuses on using a learning algorithm to optimize PCB with very limited training data, so that PCB can have the ability to predict and evaluate traffic scenarios similarly to human drivers. 80 seconds of human driving data was collected in low-speed (< 30miles/h) car-following scenarios. In the low-speed car-following tests, PCB was able to perform more human-like carfollowing after learning. A more general 120 kilometer-long simulation showed that PCB performs robustly even in scenarios that are not part of the training set.

Manufacture and characterization of breast tissue phantoms for emulating benign lesions

NASA Astrophysics Data System (ADS)

Villamarín, J. A.; Rojas, M. A.; Potosi, O. M.; Narváez-Semanate, J. L.; Gaviria, C.

2017-11-01

Phantoms elaboration has turned a very important field of study during the last decades due to its applications in medicine. These objects are capable of emulating or mimicking acoustically biological tissues in which parameters like speed of sound (SOS) and attenuation are successfully attained. However, these materials are expensive depending on their characteristics (USD 460.00 - 6000.00) and is difficult to have precise measurements because of their composition. This paper presents the elaboration and characterization of low cost ( USD $25.00) breast phantoms which emulate histological normality and pathological conditions in order to support algorithm calibration procedures in imaging diagnosis. Quantitative ultrasound (QUS) was applied to estimate SOS and attenuation values for breast tissue (background) and benign lesions (fibroadenoma and cysts). Results showed values of the SOS and attenuation for the background between 1410 - 1450 m/s and 0.40 - 0.55 dB/cm at 1 MHz sampling frequency, respectively. On the other hand, the SOS obtained for the lesions ranges from 1350 to 1700 m/s and attenuation values between 0.50 - 1.80 dB/cm at 1 MHz. Finally, the fabricated phantoms allowed for obtaining ultrasonograms comparable with real ones whose acoustic parameters are in agree with those reported in the literature.

A data-driven emulation framework for representing water-food nexus in a changing cold region

NASA Astrophysics Data System (ADS)

Nazemi, A.; Zandmoghaddam, S.; Hatami, S.

2017-12-01

Water resource systems are under increasing pressure globally. Growing population along with competition between water demands and emerging effects of climate change have caused enormous vulnerabilities in water resource management across many regions. Diagnosing such vulnerabilities and provision of effective adaptation strategies requires the availability of simulation tools that can adequately represent the interactions between competing water demands for limiting water resources and inform decision makers about the critical vulnerability thresholds under a range of potential natural and anthropogenic conditions. Despite a significant progress in integrated modeling of water resource systems, regional models are often unable to fully represent the contemplating dynamics within the key elements of water resource systems locally. Here we propose a data-driven approach to emulate a complex regional water resource system model developed for Oldman River Basin in southern Alberta, Canada. The aim of the emulation is to provide a detailed understanding of the trade-offs and interaction at the Oldman Reservoir, which is the key to flood control and irrigated agriculture in this over-allocated semi-arid cold region. Different surrogate models are developed to represent the dynamic of irrigation demand and withdrawal as well as reservoir evaporation and release individually. The nan-falsified offline models are then integrated through the water balance equation at the reservoir location to provide a coupled model for representing the dynamic of reservoir operation and water allocation at the local scale. The performance of individual and integrated models are rigorously examined and sources of uncertainty are highlighted. To demonstrate the practical utility of such surrogate modeling approach, we use the integrated data-driven model for examining the trade-off in irrigation water supply, reservoir storage and release under a range of changing climate, upstream

Artificial cavities enhance breeding bird densities in managed cottonwood forests

USGS Publications Warehouse

Twedt, D.J.; Henne-Kerr, J.L.

2001-01-01

The paucity of natural cavities within short-rotation hardwood agroforests restricts occupancy by cavity-nesting birds. However, providing 1.6 artificial nesting cavities (nest boxes)/ha within 3- to 10-year-old managed cottonwood forests in the Mississippi Alluvial Valley increased territory density of cavity-nesting birds. Differences in territory densities between forests with and without nest boxes increased as stands aged. Seven bird species initiated 38 nests in 173 boxes during 1997 and 39 nests in 172 boxes during 1998. Prothonotary warblers (Protonotaria citrea) and eastern bluebirds (Sialia sialis) accounted for 67% of nests; nearly all warbler nests were in 1.8-L, plastic-coated cardboard (paper) boxes, whereas bluebird nests were divided between paper boxes and 3.5-L wooden boxes. Larger-volume (16.5-L) wooden nest boxes were used by eastern screech owls (Otus asio) and great crested flycatchers (Myiarchus crinitus), but this box type often was usurped by honey bees (Apis mellifera). To enhance territory densities of cavity-nesting birds in cottonwood agroforests, we recommend placement of plastic-coated paper nest boxes, at a density of 0.5/ha, after trees are >4 years old but at least 2 years before anticipated timber harvest.

Real-time high speed generator system emulation with hardware-in-the-loop application

NASA Astrophysics Data System (ADS)

Stroupe, Nicholas

The emerging emphasis and benefits of distributed generation on smaller scale networks has prompted much attention and focus to research in this field. Much of the research that has grown in distributed generation has also stimulated the development of simulation software and techniques. Testing and verification of these distributed power networks is a complex task and real hardware testing is often desired. This is where simulation methods such as hardware-in-the-loop become important in which an actual hardware unit can be interfaced with a software simulated environment to verify proper functionality. In this thesis, a simulation technique is taken one step further by utilizing a hardware-in-the-loop technique to emulate the output voltage of a generator system interfaced to a scaled hardware distributed power system for testing. The purpose of this thesis is to demonstrate a new method of testing a virtually simulated generation system supplying a scaled distributed power system in hardware. This task is performed by using the Non-Linear Loads Test Bed developed by the Energy Conversion and Integration Thrust at the Center for Advanced Power Systems. This test bed consists of a series of real hardware developed converters consistent with the Navy's All-Electric-Ship proposed power system to perform various tests on controls and stability under the expected non-linear load environment of the Navy weaponry. This test bed can also explore other distributed power system research topics and serves as a flexible hardware unit for a variety of tests. In this thesis, the test bed will be utilized to perform and validate this newly developed method of generator system emulation. In this thesis, the dynamics of a high speed permanent magnet generator directly coupled with a micro turbine are virtually simulated on an FPGA in real-time. The calculated output stator voltage will then serve as a reference for a controllable three phase inverter at the input of the test bed

Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration.

PubMed

Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M

2017-11-14

Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

Differential timing and latitudinal variation in sex ratio of Aquatic Warblers during the autumn migration

NASA Astrophysics Data System (ADS)

Wojczulanis-Jakubas, Katarzyna; Chrostek, Małgorzata E.; Jiguet, Frédéric; Martínez, Carlos Zumalacárregui; Miguélez, David; Neto, Júlio M.

2017-12-01

Differential migration has been extensively reported in spring, but less so in autumn, particularly in relation to sex in monomorphic bird species. Here, we analysed the autumn passage of a monomorphic, globally threatened passerine, the Aquatic Warbler Acrocephalus paludicola throughout Western Europe, with regard to age and sex. We showed that, overall, adults migrated earlier than first-year birds, and males migrated earlier than females during the autumn migration. This may be caused by an overall social dominance of adults over immatures, and differentiated migration strategy of males and females. In addition, we found male-skewed sex proportions, with a tendency to an equalised ratio in more southern stopover sites. This may indicate a male bias in the global population or different migration strategies of the sexes. Differential migration may cause the age and sex classes to be exposed differently to various threats affecting demographic structure of the species.

Using Student Group Work in Higher Education to Emulate Professional Communities of Practice

ERIC Educational Resources Information Center

Fearon, Colm; McLaughlin, Heather; Eng, Tan Yoke

2012-01-01

Purpose: The purpose of this paper is to discuss the value of social learning from group work that emulates a professional community of practice. Design/methodology/approach: A thought piece that first, examines the role of group-work projects as part of social learning, then outlines key arguments for social learning based upon applying a…

Brain-Inspired Photonic Signal Processor for Generating Periodic Patterns and Emulating Chaotic Systems

NASA Astrophysics Data System (ADS)

Antonik, Piotr; Haelterman, Marc; Massar, Serge

2017-05-01

Reservoir computing is a bioinspired computing paradigm for processing time-dependent signals. Its hardware implementations have received much attention because of their simplicity and remarkable performance on a series of benchmark tasks. In previous experiments, the output was uncoupled from the system and, in most cases, simply computed off-line on a postprocessing computer. However, numerical investigations have shown that feeding the output back into the reservoir opens the possibility of long-horizon time-series forecasting. Here, we present a photonic reservoir computer with output feedback, and we demonstrate its capacity to generate periodic time series and to emulate chaotic systems. We study in detail the effect of experimental noise on system performance. In the case of chaotic systems, we introduce several metrics, based on standard signal-processing techniques, to evaluate the quality of the emulation. Our work significantly enlarges the range of tasks that can be solved by hardware reservoir computers and, therefore, the range of applications they could potentially tackle. It also raises interesting questions in nonlinear dynamics and chaos theory.

Kernel-based Linux emulation for Plan 9.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minnich, Ronald G.

2010-09-01

CNKemu is a kernel-based system for the 9k variant of the Plan 9 kernel. It is designed to provide transparent binary support for programs compiled for IBM's Compute Node Kernel (CNK) on the Blue Gene series of supercomputers. This support allows users to build applications with the standard Blue Gene toolchain, including C++ and Fortran compilers. While the CNK is not Linux, IBM designed the CNK so that the user interface has much in common with the Linux 2.0 system call interface. The Plan 9 CNK emulator hence provides the foundation of kernel-based Linux system call support on Plan 9.more » In this paper we discuss cnkemu's implementation and some of its more interesting features, such as the ability to easily intermix Plan 9 and Linux system calls.« less

Development of a Radio Frequency Space Environment Path Emulator for Evaluating Spacecraft Ranging Hardware

NASA Technical Reports Server (NTRS)

Mitchell, Jason W.; Baldwin, Philip J.; Kurichh, Rishi; Naasz, Bo J.; Luquette, Richard J.

2007-01-01

The Formation Flying Testbed (FFTB) at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) provides a hardware-in-the-loop test environment for formation navigation and control. The facility is evolving as a modular, hybrid, dynamic simulation facility for end-to-end guidance, navigation and. control (GN&C) design and analysis of formation flying spacecraft. The core capabilities of the FFTB, as a platform for testing critical hardware and software algorithms in-the-loop, have expanded to include S-band Radio Frequency (RF) modems for inter-spacecraft communication and ranging. To enable realistic simulations that require RF ranging sensors for relative navigation, a mechanism is needed to buffer the RF signals exchanged between spacecraft that accurately emulates the dynamic environment through which the RF signals travel, including the effects of medium, moving platforms, and radiated power. The Path Emulator for RF Signals (PERFS), currently under development at NASA GSFC, provides this capability. The function and performance of a prototype device are presented.

Individual quality explains association between plumage colouration, arrival dates and mate acquisition in yellow warblers (Setophaga petechia).

PubMed

Jones, Teri B; Drake, Anna; Green, David J

2014-05-07

In many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. We then evaluated whether winter habitat use (inferred using δ13C and δ15N signatures of winter grown greater-coverts) influenced alternate plumage colouration, after controlling for individual quality using basic plumage colouration. Finally, we investigated whether basic and alternate plumage colouration influenced arrival dates, mate acquisition, breeding phenology and reproductive success of yellow warblers breeding in southern (Revelstoke, B.C.) and arctic (Inuvik, N.W.T.) Canada. The colour (chroma and hue) of tail feathers, grown on the breeding grounds, was not related to subsequent winter habitat use. Greater covert and tail feather colour (chroma and hue) were correlated, suggesting genetics and/or individual quality played a role in pigment deposition. After controlling for individual difference in tail colour, δ13C values did not explain any variation in greater covert colour, but birds with high δ15N signatures had greater coverts with higher chroma. Male arrival dates varied with tail chroma in Revelstoke and tail hue in Inuvik. Males that arrived early paired with older and/or more colourful mates that initiated clutches earlier, and at one site (Revelstoke) were more likely to fledge young. In addition, in Revelstoke (but not Inuvik) males with high tail hue also acquired more colourful mates. In contrast, after controlling for individual differences in tail colour, greater covert colour did not affect male arrival date, the quality of the mate obtained or reproductive success in either population. Our results suggest that plumage colour effects on breeding phenology and mate acquisition result from differences in the intrinsic quality of

Individual quality explains association between plumage colouration, arrival dates and mate acquisition in yellow warblers (Setophaga petechia)

PubMed Central

2014-01-01

Background In many bird species colour traits influence social dominance and breeding success. In our study we first evaluated whether the colour of the basic plumage (tail feathers grown at the end of the breeding season), that provides an index of individual quality, influenced winter habitat use by yellow warblers. We then evaluated whether winter habitat use (inferred using δ13C and δ15N signatures of winter grown greater-coverts) influenced alternate plumage colouration, after controlling for individual quality using basic plumage colouration. Finally, we investigated whether basic and alternate plumage colouration influenced arrival dates, mate acquisition, breeding phenology and reproductive success of yellow warblers breeding in southern (Revelstoke, B.C.) and arctic (Inuvik, N.W.T.) Canada. Results The colour (chroma and hue) of tail feathers, grown on the breeding grounds, was not related to subsequent winter habitat use. Greater covert and tail feather colour (chroma and hue) were correlated, suggesting genetics and/or individual quality played a role in pigment deposition. After controlling for individual difference in tail colour, δ13C values did not explain any variation in greater covert colour, but birds with high δ15N signatures had greater coverts with higher chroma. Male arrival dates varied with tail chroma in Revelstoke and tail hue in Inuvik. Males that arrived early paired with older and/or more colourful mates that initiated clutches earlier, and at one site (Revelstoke) were more likely to fledge young. In addition, in Revelstoke (but not Inuvik) males with high tail hue also acquired more colourful mates. In contrast, after controlling for individual differences in tail colour, greater covert colour did not affect male arrival date, the quality of the mate obtained or reproductive success in either population. Conclusions Our results suggest that plumage colour effects on breeding phenology and mate acquisition result from differences

Causal knowledge and imitation/emulation switching in chimpanzees (Pan troglodytes) and children (Homo sapiens).

PubMed

Horner, Victoria; Whiten, Andrew

2005-07-01

This study explored whether the tendency of chimpanzees and children to use emulation or imitation to solve a tool-using task was a response to the availability of causal information. Young wild-born chimpanzees from an African sanctuary and 3- to 4-year-old children observed a human demonstrator use a tool to retrieve a reward from a puzzle-box. The demonstration involved both causally relevant and irrelevant actions, and the box was presented in each of two conditions: opaque and clear. In the opaque condition, causal information about the effect of the tool inside the box was not available, and hence it was impossible to differentiate between the relevant and irrelevant parts of the demonstration. However, in the clear condition causal information was available, and subjects could potentially determine which actions were necessary. When chimpanzees were presented with the opaque box, they reproduced both the relevant and irrelevant actions, thus imitating the overall structure of the task. When the box was presented in the clear condition they instead ignored the irrelevant actions in favour of a more efficient, emulative technique. These results suggest that emulation is the favoured strategy of chimpanzees when sufficient causal information is available. However, if such information is not available, chimpanzees are prone to employ a more comprehensive copy of an observed action. In contrast to the chimpanzees, children employed imitation to solve the task in both conditions, at the expense of efficiency. We suggest that the difference in performance of chimpanzees and children may be due to a greater susceptibility of children to cultural conventions, perhaps combined with a differential focus on the results, actions and goals of the demonstrator.

Emulation of anamorphic imaging on the SHARP extreme ultraviolet mask microscope

DOE PAGES

Benk, Markus P.; Wojdyla, Antoine; Chao, Weilun; ...

2016-07-12

The SHARP high-numerical aperture actinic reticle review project is a synchrotron-based, extreme ultraviolet (EUV) microscope dedicated to photomask research. SHARP emulates the illumination and imaging conditions of current EUV lithography scanners and those several generations into the future. An anamorphic imaging optic with increased mask-side numerical aperture (NA) in the horizontal and increased demagnification in the vertical direction has been proposed in this paper to overcome limitations of current multilayer coatings and extend EUV lithography beyond 0.33 NA. Zoneplate lenses with an anamorphic 4×/8× NA of 0.55 are fabricated and installed in the SHARP microscope to emulate anamorphic imaging. SHARP’smore » Fourier synthesis illuminator with a range of angles exceeding the collected solid angle of the newly designed elliptical zoneplates can produce arbitrary angular source spectra matched to anamorphic imaging. A target with anamorphic dense features down to 50-nm critical dimension is fabricated using 40 nm of nickel as the absorber. In a demonstration experiment, anamorphic imaging at 0.55 4×/8× NA and 6 deg central ray angle (CRA) is compared with conventional imaging at 0.5 4× NA and 8 deg CRA. A significant contrast loss in horizontal features is observed in the conventional images. Finally, the anamorphic images show the same image quality in the horizontal and vertical directions.« less

Emulation of anamorphic imaging on the SHARP extreme ultraviolet mask microscope

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benk, Markus P.; Wojdyla, Antoine; Chao, Weilun

The SHARP high-numerical aperture actinic reticle review project is a synchrotron-based, extreme ultraviolet (EUV) microscope dedicated to photomask research. SHARP emulates the illumination and imaging conditions of current EUV lithography scanners and those several generations into the future. An anamorphic imaging optic with increased mask-side numerical aperture (NA) in the horizontal and increased demagnification in the vertical direction has been proposed in this paper to overcome limitations of current multilayer coatings and extend EUV lithography beyond 0.33 NA. Zoneplate lenses with an anamorphic 4×/8× NA of 0.55 are fabricated and installed in the SHARP microscope to emulate anamorphic imaging. SHARP’smore » Fourier synthesis illuminator with a range of angles exceeding the collected solid angle of the newly designed elliptical zoneplates can produce arbitrary angular source spectra matched to anamorphic imaging. A target with anamorphic dense features down to 50-nm critical dimension is fabricated using 40 nm of nickel as the absorber. In a demonstration experiment, anamorphic imaging at 0.55 4×/8× NA and 6 deg central ray angle (CRA) is compared with conventional imaging at 0.5 4× NA and 8 deg CRA. A significant contrast loss in horizontal features is observed in the conventional images. Finally, the anamorphic images show the same image quality in the horizontal and vertical directions.« less

Entrainment and motor emulation approaches to joint action: Alternatives or complementary approaches?

PubMed

Colling, Lincoln J; Williamson, Kellie

2014-01-01

Joint actions, such as music and dance, rely crucially on the ability of two, or more, agents to align their actions with great temporal precision. Within the literature that seeks to explain how this action alignment is possible, two broad approaches have appeared. The first, what we term the entrainment approach, has sought to explain these alignment phenomena in terms of the behavioral dynamics of the system of two agents. The second, what we term the emulator approach, has sought to explain these alignment phenomena in terms of mechanisms, such as forward and inverse models, that are implemented in the brain. They have often been pitched as alternative explanations of the same phenomena; however, we argue that this view is mistaken, because, as we show, these two approaches are engaged in distinct, and not mutually exclusive, explanatory tasks. While the entrainment approach seeks to uncover the general laws that govern behavior the emulator approach seeks to uncover mechanisms. We argue that is possible to do both and that the entrainment approach must pay greater attention to the mechanisms that support the behavioral dynamics of interest. In short, the entrainment approach must be transformed into a neuroentrainment approach by adopting a mechanistic view of explanation and by seeking mechanisms that are implemented in the brain.

Space Link Extension (SLE) Emulation for High-Throughput Network Communication

NASA Technical Reports Server (NTRS)

Murawski, Robert W.; Tchorowski, Nicole; Golden, Bert

2014-01-01

As the data rate requirements for space communications increases, significant stress is placed not only on the wireless satellite communication links, but also on the ground networks which forward data from end-users to remote ground stations. These wide area network (WAN) connections add delay and jitter to the end-to-end satellite communication link, effects which can have significant impacts on the wireless communication link. It is imperative that any ground communication protocol can react to these effects such that the ground network does not become a bottleneck in the communication path to the satellite. In this paper, we present our SCENIC Emulation Lab testbed which was developed to test the CCSDS SLE protocol implementations proposed for use on future NASA communication networks. Our results show that in the presence of realistic levels of network delay, high-throughput SLE communication links can experience significant data rate throttling. Based on our observations, we present some insight into why this data throttling happens, and trace the probable issue back to non-optimal blocking communication which is sup-ported by the CCSDS SLE API recommended practices. These issues were presented as well to the SLE implementation developers which, based on our reports, developed a new release for SLE which we show fixes the SLE blocking issue and greatly improves the protocol throughput. In this paper, we also discuss future developments for our end-to-end emulation lab and how these improvements can be used to develop and test future space communication technologies.

Combining super-ensembles and statistical emulation to improve a regional climate and vegetation model

NASA Astrophysics Data System (ADS)

Hawkins, L. R.; Rupp, D. E.; Li, S.; Sarah, S.; McNeall, D. J.; Mote, P.; Betts, R. A.; Wallom, D.

2017-12-01

Changing regional patterns of surface temperature, precipitation, and humidity may cause ecosystem-scale changes in vegetation, altering the distribution of trees, shrubs, and grasses. A changing vegetation distribution, in turn, alters the albedo, latent heat flux, and carbon exchanged with the atmosphere with resulting feedbacks onto the regional climate. However, a wide range of earth-system processes that affect the carbon, energy, and hydrologic cycles occur at sub grid scales in climate models and must be parameterized. The appropriate parameter values in such parameterizations are often poorly constrained, leading to uncertainty in predictions of how the ecosystem will respond to changes in forcing. To better understand the sensitivity of regional climate to parameter selection and to improve regional climate and vegetation simulations, we used a large perturbed physics ensemble and a suite of statistical emulators. We dynamically downscaled a super-ensemble (multiple parameter sets and multiple initial conditions) of global climate simulations using a 25-km resolution regional climate model HadRM3p with the land-surface scheme MOSES2 and dynamic vegetation module TRIFFID. We simultaneously perturbed land surface parameters relating to the exchange of carbon, water, and energy between the land surface and atmosphere in a large super-ensemble of regional climate simulations over the western US. Statistical emulation was used as a computationally cost-effective tool to explore uncertainties in interactions. Regions of parameter space that did not satisfy observational constraints were eliminated and an ensemble of parameter sets that reduce regional biases and span a range of plausible interactions among earth system processes were selected. This study demonstrated that by combining super-ensemble simulations with statistical emulation, simulations of regional climate could be improved while simultaneously accounting for a range of plausible land

Biorobotics: using robots to emulate and investigate agile locomotion.

PubMed

Ijspeert, Auke J

2014-10-10

The graceful and agile movements of animals are difficult to analyze and emulate because locomotion is the result of a complex interplay of many components: the central and peripheral nervous systems, the musculoskeletal system, and the environment. The goals of biorobotics are to take inspiration from biological principles to design robots that match the agility of animals, and to use robots as scientific tools to investigate animal adaptive behavior. Used as physical models, biorobots contribute to hypothesis testing in fields such as hydrodynamics, biomechanics, neuroscience, and prosthetics. Their use may contribute to the design of prosthetic devices that more closely take human locomotion principles into account. Copyright © 2014, American Association for the Advancement of Science.

Characterization of a Prototype Radio Frequency Space Environment Path Emulator for Evaluating Spacecraft Ranging Hardware

NASA Technical Reports Server (NTRS)

Mitchell, Jason W.; Baldwin, Philip J.; Kurichh, Rishi; Naasz, Bo J.; Luquette, Richard J.

2007-01-01

The Formation Flying Testbed (FFTB) at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) provides a hardware-in-the-loop test environment for formation navigation and control. The facility is evolving as a modular, hybrid, dynamic simulation facility for end-to-end guidance, navigation and control (GN&C) design and analysis of formation flying spacecraft. The core capabilities of the FFTB, as a platform for testing critical hardware and software algorithms in-the-loop, have expanded to include S-band Radio Frequency (RF) modems for interspacecraft communication and ranging. To enable realistic simulations that require RF ranging sensors for relative navigation, a mechanism is needed to buffer the RF signals exchanged between spacecraft that accurately emulates the dynamic environment through which the RF signals travel, including the effects of the medium, moving platforms, and radiated power. The Path Emulator for Radio Frequency Signals (PERFS), currently under development at NASA GSFC, provides this capability. The function and performance of a prototype device are presented.

Multi-level emulation of a volcanic ash transport and dispersion model to quantify sensitivity to uncertain parameters

NASA Astrophysics Data System (ADS)

Harvey, Natalie J.; Huntley, Nathan; Dacre, Helen F.; Goldstein, Michael; Thomson, David; Webster, Helen

2018-01-01

Following the disruption to European airspace caused by the eruption of Eyjafjallajökull in 2010 there has been a move towards producing quantitative predictions of volcanic ash concentration using volcanic ash transport and dispersion simulators. However, there is no formal framework for determining the uncertainties of these predictions and performing many simulations using these complex models is computationally expensive. In this paper a Bayesian linear emulation approach is applied to the Numerical Atmospheric-dispersion Modelling Environment (NAME) to better understand the influence of source and internal model parameters on the simulator output. Emulation is a statistical method for predicting the output of a computer simulator at new parameter choices without actually running the simulator. A multi-level emulation approach is applied using two configurations of NAME with different numbers of model particles. Information from many evaluations of the computationally faster configuration is combined with results from relatively few evaluations of the slower, more accurate, configuration. This approach is effective when it is not possible to run the accurate simulator many times and when there is also little prior knowledge about the influence of parameters. The approach is applied to the mean ash column loading in 75 geographical regions on 14 May 2010. Through this analysis it has been found that the parameters that contribute the most to the output uncertainty are initial plume rise height, mass eruption rate, free tropospheric turbulence levels and precipitation threshold for wet deposition. This information can be used to inform future model development and observational campaigns and routine monitoring. The analysis presented here suggests the need for further observational and theoretical research into parameterisation of atmospheric turbulence. Furthermore it can also be used to inform the most important parameter perturbations for a small operational

IBM NJE protocol emulator for VAX/VMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Engert, D.E.

1981-01-01

Communications software has been written at Argonne National Laboratory to enable a VAX/VMS system to participate as an end-node in a standard IBM network by emulating the Network Job Entry (NJE) protocol. NJE is actually a collection of programs that support job networking for the operating systems used on most large IBM-compatible computers (e.g., VM/370, MVS with JES2 or JES3, SVS, MVT with ASP or HASP). Files received by the VAX can be printed or saved in user-selected disk files. Files sent to the network can be routed to any node in the network for printing, punching, or job submission,more » as well as to a VM/370 user's virtual reader. Files sent from the VAX are queued and transmitted asynchronously to allow users to perform other work while files are awaiting transmission. No changes are required to the IBM software.« less

Microswitch and keyboard-emulator technology to facilitate the writing performance of persons with extensive motor disabilities.

PubMed

Lancioni, Giulio E; Singh, Nirbhay N; O'Reilly, Mark F; Sigafoos, Jeff; Green, Vanessa; Oliva, Doretta; Lang, Russell

2011-01-01

This study assessed the effectiveness of microswitches for simple responses (i.e., partial hand closure, vocalization, and hand stroking) and a keyboard emulator to facilitate the writing performance of three participants with extensive motor disabilities. The study was carried out according to an ABAB design. During the A phases, the participants (one child and two adults) were to write using the responses and technology available to them prior to this study. During the B phases, they used the new responses and technology. Data showed that two of the three participants had a faster writing performance during the B phases while the third participant had a slower writing performance. All three participants indicated a clear preference for the use of the new responses and technology, which were considered relatively easy and comfortable to manage and did not seem to cause any specific signs of tiredness. Implications of the findings are discussed. Copyright © 2010 Elsevier Ltd. All rights reserved.

Age-specific survival of male golden-cheeked warblers on the Fort Hood Military Reservation, Texas

USGS Publications Warehouse

Duarte, Adam; Hines, James E.; Nichols, James D.; Hatfield, Jeffrey S.; Weckerly, Floyd W.

2014-01-01

Population models are essential components of large-scale conservation and management plans for the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia; hereafter GCWA). However, existing models are based on vital rate estimates calculated using relatively small data sets that are now more than a decade old. We estimated more current, precise adult and juvenile apparent survival (Φ) probabilities and their associated variances for male GCWAs. In addition to providing estimates for use in population modeling, we tested hypotheses about spatial and temporal variation in Φ. We assessed whether a linear trend in Φ or a change in the overall mean Φ corresponded to an observed increase in GCWA abundance during 1992-2000 and if Φ varied among study plots. To accomplish these objectives, we analyzed long-term GCWA capture-resight data from 1992 through 2011, collected across seven study plots on the Fort Hood Military Reservation using a Cormack-Jolly-Seber model structure within program MARK. We also estimated Φ process and sampling variances using a variance-components approach. Our results did not provide evidence of site-specific variation in adult Φ on the installation. Because of a lack of data, we could not assess whether juvenile Φ varied spatially. We did not detect a strong temporal association between GCWA abundance and Φ. Mean estimates of Φ for adult and juvenile male GCWAs for all years analyzed were 0.47 with a process variance of 0.0120 and a sampling variance of 0.0113 and 0.28 with a process variance of 0.0076 and a sampling variance of 0.0149, respectively. Although juvenile Φ did not differ greatly from previous estimates, our adult Φ estimate suggests previous GCWA population models were overly optimistic with respect to adult survival. These updated Φ probabilities and their associated variances will be incorporated into new population models to assist with GCWA conservation decision making.

Public acceptance of disturbance-based forest management: factors influencing support

Treesearch

Christine S. Olsen; Angela L. Mallon; Bruce A. Shindler

2012-01-01

Growing emphasis on ecosystem and landscape-level forest management across North America has spurred an examination of alternative management strategies which focus on emulating dynamic natural disturbance processes, particularly those associated with forest fire regimes. This topic is the cornerstone of research in the Blue River Landscape Study (BRLS) on the...

Emulation of recharge and evapotranspiration processes in shallow groundwater systems

NASA Astrophysics Data System (ADS)

Doble, Rebecca C.; Pickett, Trevor; Crosbie, Russell S.; Morgan, Leanne K.; Turnadge, Chris; Davies, Phil J.

2017-12-01

In shallow groundwater systems, recharge and evapotranspiration are highly sensitive to changes in the depth to water table. To effectively model these fluxes, complex functions that include soil and vegetation properties are often required. Model emulation (surrogate modelling or meta-modelling) can provide a means of incorporating detailed conceptualisation of recharge and evapotranspiration processes, while maintaining the numerical tractability and computational performance required for regional scale groundwater models and uncertainty analysis. A method for emulating recharge and evapotranspiration processes in groundwater flow models was developed, and applied to the South East region of South Australia and western Victoria, which is characterised by shallow groundwater, wetlands and coastal lakes. The soil-vegetation-atmosphere transfer (SVAT) model WAVES was used to generate relationships between net recharge (diffuse recharge minus evapotranspiration from groundwater) and depth to water table for different combinations of climate, soil and land cover types. These relationships, which mimicked previously described soil, vegetation and groundwater behaviour, were combined into a net recharge lookup table. The segmented evapotranspiration package in MODFLOW was adapted to select values of net recharge from the lookup table depending on groundwater depth, and the climate, soil and land use characteristics of each cell. The model was found to be numerically robust in steady state testing, had no major increase in run time, and would be more efficient than tightly-coupled modelling approaches. It made reasonable predictions of net recharge and groundwater head compared with remotely sensed estimates of net recharge and a standard MODFLOW comparison model. In particular, the method was better able to predict net recharge and groundwater head in areas with steep hydraulic gradients.

Responses of a Federally Endangered Songbird to Understory Thinning in Oak-Juniper Woodlands

NASA Astrophysics Data System (ADS)

Long, Ashley M.; Marshall, Mike E.; Morrison, Michael L.; Hays, K. Brian; Farrell, Shannon L.

2017-04-01

Wildlife conservation and management on military lands must be accomplished in the context of military readiness, which often includes ground-based training that is perceived to conflict with wildlife needs and environmental regulations. From 2008‒2012, we examined territory density, pairing success, and fledging success of the federally endangered golden-cheeked warbler ( Setophaga chrysoparia; hereafter warbler) in relation to removal of small-diameter trees from the understory of mature oak-juniper ( Quercus-Juniperus) woodland at the 87,890 ha Fort Hood Military Reservation in central Texas. Understory thinning created troop maneuver lanes, but left canopy vegetation intact. Warbler density, pairing success, and fledging success were similar across thinned and control sites. We found that warbler pairing and fledging success were best predicted by Ecological site (hereafter Ecosite), an indicator of hardwood tree species composition. Warbler pairing and fledging success were about 1.5 and 1.6 times higher, respectively, for territories dominated by the Low Stony Hill Ecosite than territories dominated by the Redlands Ecosite. Our results indicate that understory thinning for military training purposes did not have a negative effect on warblers at Fort Hood in the manner tested, and suggest that removal of smaller trees from the understory in a way that replicates historic conditions may elicit neutral responses from this forest-dependent songbird. Quantifying wildlife responses to military activities provides the Department of Defense and US Fish and Wildlife Service with data to guide conservation of threatened and endangered species on Department of Defense facilities while maintaining the military mission, and supports wildlife management efforts on other public and private lands.

Programming a Detector Emulator on NI's FlexRIO Platform

NASA Astrophysics Data System (ADS)

Gervais, Michelle; Crawford, Christopher; Sprow, Aaron; Nab Collaboration

2017-09-01

Recently digital detector emulators have been on the rise as a means to test data acquisition systems and analysis toolkits from a well understood data set. National Instruments' PXIe-7962R FPGA module and Active Technologies AT-1212 DAC module provide a customizable platform for analog output. Using a graphical programming language, we have developed a system capable of producing two time-correlated channels of analog output which sample unique amplitude spectra to mimic nuclear physics experiments. This system will be used to model the Nab experiment, in which a prompt beta decay electron is followed by a slow proton according to a defined time distribution. We will present the results of our work and discuss further development potential. DOE under Contract DE-SC0008107.

Test of partners in flight effective detection distance for Cerulean Warbler / Evaluación de distancia efectiva de detección para la Reinita Cerúlea (Dendroica cerulea) seleccionada por Compañeros En Vuelo

Treesearch

Paul Hamel; Melinda J. Welton; Carl G. Smith; Robert R. Ford

2008-01-01

Estimation of population sizes of North American avian species has been attempted in the North American Landbird Conservation Plan. Such estimated numbers have considerable conservation value as starting points to estimate extinction probability, as was done for Cerulean Warbler (Dendroica cerulea) during the U.S. Fish and Wildlife Service evaluation of the petition to...

Using Big Data to Emulate a Target Trial When a Randomized Trial Is Not Available.

PubMed

Hernán, Miguel A; Robins, James M

2016-04-15

Ideally, questions about comparative effectiveness or safety would be answered using an appropriately designed and conducted randomized experiment. When we cannot conduct a randomized experiment, we analyze observational data. Causal inference from large observational databases (big data) can be viewed as an attempt to emulate a randomized experiment-the target experiment or target trial-that would answer the question of interest. When the goal is to guide decisions among several strategies, causal analyses of observational data need to be evaluated with respect to how well they emulate a particular target trial. We outline a framework for comparative effectiveness research using big data that makes the target trial explicit. This framework channels counterfactual theory for comparing the effects of sustained treatment strategies, organizes analytic approaches, provides a structured process for the criticism of observational studies, and helps avoid common methodologic pitfalls. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Emulating multiple inheritance in Fortran 2003/2008

DOE PAGES

Morris, Karla

2015-01-24

Although the high-performance computing (HPC) community increasingly embraces object-oriented programming (OOP), most HPC OOP projects employ the C++ programming language. Until recently, Fortran programmers interested in mining the benefits of OOP had to emulate OOP in Fortran 90/95. The advent of widespread compiler support for Fortran 2003 now facilitates explicitly constructing object-oriented class hierarchies via inheritance and leveraging related class behaviors such as dynamic polymorphism. Although C++ allows a class to inherit from multiple parent classes, Fortran and several other OOP languages restrict or prohibit explicit multiple inheritance relationships in order to circumvent several pitfalls associated with them. Nonetheless, whatmore » appears as an intrinsic feature in one language can be modeled as a user-constructed design pattern in another language. The present paper demonstrates how to apply the facade structural design pattern to support a multiple inheritance class relationship in Fortran 2003. As a result, the design unleashes the power of the associated class relationships for modeling complicated data structures yet avoids the ambiguities that plague some multiple inheritance scenarios.« less

Piecewise linear emulator of the nonlinear Schrödinger equation and the resulting analytic solutions for Bose-Einstein condensates.

PubMed

Theodorakis, Stavros

2003-06-01

We emulate the cubic term Psi(3) in the nonlinear Schrödinger equation by a piecewise linear term, thus reducing the problem to a set of uncoupled linear inhomogeneous differential equations. The resulting analytic expressions constitute an excellent approximation to the exact solutions, as is explicitly shown in the case of the kink, the vortex, and a delta function trap. Such a piecewise linear emulation can be used for any differential equation where the only nonlinearity is a Psi(3) one. In particular, it can be used for the nonlinear Schrödinger equation in the presence of harmonic traps, giving analytic Bose-Einstein condensate solutions that reproduce very accurately the numerically calculated ones in one, two, and three dimensions.

Bayesian History Matching of Complex Infectious Disease Models Using Emulation: A Tutorial and a Case Study on HIV in Uganda

PubMed Central

Andrianakis, Ioannis; Vernon, Ian R.; McCreesh, Nicky; McKinley, Trevelyan J.; Oakley, Jeremy E.; Nsubuga, Rebecca N.; Goldstein, Michael; White, Richard G.

2015-01-01

Advances in scientific computing have allowed the development of complex models that are being routinely applied to problems in disease epidemiology, public health and decision making. The utility of these models depends in part on how well they can reproduce empirical data. However, fitting such models to real world data is greatly hindered both by large numbers of input and output parameters, and by long run times, such that many modelling studies lack a formal calibration methodology. We present a novel method that has the potential to improve the calibration of complex infectious disease models (hereafter called simulators). We present this in the form of a tutorial and a case study where we history match a dynamic, event-driven, individual-based stochastic HIV simulator, using extensive demographic, behavioural and epidemiological data available from Uganda. The tutorial describes history matching and emulation. History matching is an iterative procedure that reduces the simulator's input space by identifying and discarding areas that are unlikely to provide a good match to the empirical data. History matching relies on the computational efficiency of a Bayesian representation of the simulator, known as an emulator. Emulators mimic the simulator's behaviour, but are often several orders of magnitude faster to evaluate. In the case study, we use a 22 input simulator, fitting its 18 outputs simultaneously. After 9 iterations of history matching, a non-implausible region of the simulator input space was identified that was times smaller than the original input space. Simulator evaluations made within this region were found to have a 65% probability of fitting all 18 outputs. History matching and emulation are useful additions to the toolbox of infectious disease modellers. Further research is required to explicitly address the stochastic nature of the simulator as well as to account for correlations between outputs. PMID:25569850

Grandparent helpers: the adaptive significance of older, postdominant helpers in the Seychelles warbler.

PubMed

Richardson, David S; Burke, Terry; Komdeur, Jan

2007-12-01

The possibility that older, often nonreproductive, individuals may engage in kin-directed cooperative behavior has been largely overlooked in the study of cooperative breeding. Here, we describe and investigate the adaptive significance of such "grandparent" helpers in the Seychelles warbler, the first bird species in which this phenomenon has been observed. On Cousin Island, over a period of 24 years, a significant proportion (13.7%) of females, but few males (3.0%), was deposed from dominant positions. Deposed females were replaced by related females. However there was no evidence that older, senescent females were stepping aside to gain greater fitness benefits by increasing the reproductive success of their offspring, rather than breeding themselves; deposed females were not postreproductive, nor was being deposed linked to age or reproductive senescence. Of the deposed females, 68% became subordinates and helped to raise group offspring, accounting for ca. 10% of subordinates in any year. Demoted females were related (r= 0.24) to the group offspring and, consequently, could gain indirect benefits through helping. As direct benefits appeared to be limited, we suggest that indirect benefits have driven the evolution of such "grandparent helpers." This study now provides evidence for a new route to cooperative breeding in birds.

Microswitch and Keyboard-Emulator Technology to Facilitate the Writing Performance of Persons with Extensive Motor Disabilities

ERIC Educational Resources Information Center

Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Green, Vanessa; Oliva, Doretta; Lang, Russell

2011-01-01

This study assessed the effectiveness of microswitches for simple responses (i.e., partial hand closure, vocalization, and hand stroking) and a keyboard emulator to facilitate the writing performance of three participants with extensive motor disabilities. The study was carried out according to an ABAB design. During the A phases, the participants…

Method using in vivo quantitative spectroscopy to guide design and optimization of low-cost, compact clinical imaging devices: emulation and evaluation of multispectral imaging systems

NASA Astrophysics Data System (ADS)

Saager, Rolf B.; Baldado, Melissa L.; Rowland, Rebecca A.; Kelly, Kristen M.; Durkin, Anthony J.

2018-04-01

With recent proliferation in compact and/or low-cost clinical multispectral imaging approaches and commercially available components, questions remain whether they adequately capture the requisite spectral content of their applications. We present a method to emulate the spectral range and resolution of a variety of multispectral imagers, based on in-vivo data acquired from spatial frequency domain spectroscopy (SFDS). This approach simulates spectral responses over 400 to 1100 nm. Comparing emulated data with full SFDS spectra of in-vivo tissue affords the opportunity to evaluate whether the sparse spectral content of these imagers can (1) account for all sources of optical contrast present (completeness) and (2) robustly separate and quantify sources of optical contrast (crosstalk). We validate the approach over a range of tissue-simulating phantoms, comparing the SFDS-based emulated spectra against measurements from an independently characterized multispectral imager. Emulated results match the imager across all phantoms (<3 % absorption, <1 % reduced scattering). In-vivo test cases (burn wounds and photoaging) illustrate how SFDS can be used to evaluate different multispectral imagers. This approach provides an in-vivo measurement method to evaluate the performance of multispectral imagers specific to their targeted clinical applications and can assist in the design and optimization of new spectral imaging devices.

rpe v5: an emulator for reduced floating-point precision in large numerical simulations

NASA Astrophysics Data System (ADS)

Dawson, Andrew; Düben, Peter D.

2017-06-01

This paper describes the rpe (reduced-precision emulator) library which has the capability to emulate the use of arbitrary reduced floating-point precision within large numerical models written in Fortran. The rpe software allows model developers to test how reduced floating-point precision affects the result of their simulations without having to make extensive code changes or port the model onto specialized hardware. The software can be used to identify parts of a program that are problematic for numerical precision and to guide changes to the program to allow a stronger reduction in precision.The development of rpe was motivated by the strong demand for more computing power. If numerical precision can be reduced for an application under consideration while still achieving results of acceptable quality, computational cost can be reduced, since a reduction in numerical precision may allow an increase in performance or a reduction in power consumption. For simulations with weather and climate models, savings due to a reduction in precision could be reinvested to allow model simulations at higher spatial resolution or complexity, or to increase the number of ensemble members to improve predictions. rpe was developed with a particular focus on the community of weather and climate modelling, but the software could be used with numerical simulations from other domains.

Consider the Kirtland's Warbler

ERIC Educational Resources Information Center

Dustin, Daniel L.; Schwab, Keri A.

2008-01-01

This paper challenges the conventional wisdom of departments of parks and recreation taking sport management under their "wing." Based on a review of the sport management literature and a polling of sport management and park and recreation educators, we argue that departments of parks and recreation are but temporary refuges for migratory sport…

A robotic orbital emulator with lidar-based SLAM and AMCL for multiple entity pose estimation

NASA Astrophysics Data System (ADS)

Shen, Dan; Xiang, Xingyu; Jia, Bin; Wang, Zhonghai; Chen, Genshe; Blasch, Erik; Pham, Khanh

2018-05-01

This paper revises and evaluates an orbital emulator (OE) for space situational awareness (SSA). The OE can produce 3D satellite movements using capabilities generated from omni-wheeled robot and robotic arm motions. The 3D motion of satellite is partitioned into the movements in the equatorial plane and the up-down motions in the vertical plane. The 3D actions are emulated by omni-wheeled robot models while the up-down motions are performed by a stepped-motorcontrolled- ball along a rod (robotic arm), which is attached to the robot. Lidar only measurements are used to estimate the pose information of the multiple robots. SLAM (simultaneous localization and mapping) is running on one robot to generate the map and compute the pose for the robot. Based on the SLAM map maintained by the robot, the other robots run the adaptive Monte Carlo localization (AMCL) method to estimate their poses. The controller is designed to guide the robot to follow a given orbit. The controllability is analyzed by using a feedback linearization method. Experiments are conducted to show the convergence of AMCL and the orbit tracking performance.

Extending the Coyote emulator to dark energy models with standard w {sub 0}- w {sub a} parametrization of the equation of state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casarini, L.; Bonometto, S.A.; Tessarotto, E.

2016-08-01

We discuss an extension of the Coyote emulator to predict non-linear matter power spectra of dark energy (DE) models with a scale factor dependent equation of state of the form w = w {sub 0}+(1- a ) w {sub a} . The extension is based on the mapping rule between non-linear spectra of DE models with constant equation of state and those with time varying one originally introduced in ref. [40]. Using a series of N-body simulations we show that the spectral equivalence is accurate to sub-percent level across the same range of modes and redshift covered by the Coyotemore » suite. Thus, the extended emulator provides a very efficient and accurate tool to predict non-linear power spectra for DE models with w {sub 0}- w {sub a} parametrization. According to the same criteria we have developed a numerical code that we have implemented in a dedicated module for the CAMB code, that can be used in combination with the Coyote Emulator in likelihood analyses of non-linear matter power spectrum measurements. All codes can be found at https://github.com/luciano-casarini/pkequal.« less

Kinship and familiarity mitigate costs of social conflict between Seychelles warbler neighbors

PubMed Central

Fairfield, Eleanor A.; Komdeur, Jan; Spurgin, Lewis G.; Richardson, David S.

2017-01-01

Because virtually all organisms compete with others in their social environment, mechanisms that reduce conflict between interacting individuals are crucial for the evolution of stable families, groups, and societies. Here, we tested whether costs of social conflict over territorial space between Seychelles warblers (Acrocephalus sechellensis) are mitigated by kin-selected (genetic relatedness) or mutualistic (social familiarity) mechanisms. By measuring longitudinal changes in individuals’ body mass and telomere length, we demonstrated that the fitness costs of territoriality are driven by a complex interplay between relatedness, familiarity, local density, and sex. Physical fights were less common at territory boundaries shared between related or familiar males. In line with this, male territory owners gained mass when living next to related or familiar males and also showed less telomere attrition when living next to male kin. Importantly, these relationships were strongest in high-density areas of the population. Males also had more rapid telomere attrition when living next to unfamiliar male neighbors, but mainly when relatedness to those neighbors was also low. In contrast, neither kinship nor familiarity was linked to body mass or telomere loss in female territory owners. Our results indicate that resolving conflict over territorial space through kin-selected or mutualistic pathways can reduce both immediate energetic costs and permanent somatic damage, thus providing an important mechanism to explain fine-scale population structure and cooperation between different social units across a broad range of taxa. PMID:29073100

GW170817 falsifies dark matter emulators

NASA Astrophysics Data System (ADS)

Boran, S.; Desai, S.; Kahya, E. O.; Woodard, R. P.

2018-02-01

On August 17, 2017 the LIGO interferometers detected the gravitational wave (GW) signal (GW170817) from the coalescence of binary neutron stars. This signal was also simultaneously seen throughout the electromagnetic (EM) spectrum from radio waves to gamma rays. We point out that this simultaneous detection of GW and EM signals rules out a class of modified gravity theories, termed "dark matter emulators," which dispense with the need for dark matter by making ordinary matter couple to a different metric from that of GW. We discuss other kinds of modified gravity theories which dispense with the need for dark matter and are still viable. This simultaneous observation also provides the first observational test of Einstein's weak equivalence principle (WEP) between gravitons and photons. We estimate the Shapiro time delay due to the gravitational potential of the total dark matter distribution along the line of sight (complementary to the calculation by Abbott et al. [Astrophys. J. Lett. 848, L13 (2017)], 10.3847/2041-8213/aa920c) to be about 400 days. Using this estimate for the Shapiro delay and from the time difference of 1.7 seconds between the GW signal and gamma rays, we can constrain violations of the WEP using the parametrized post-Newtonian parameter γ , and it is given by |γGW-γEM|<9.8 ×10-8.

The impact of conservation-driven translocations on blood parasite prevalence in the Seychelles warbler.

PubMed

Fairfield, Eleanor A; Hutchings, Kimberly; Gilroy, Danielle L; Kingma, Sjouke A; Burke, Terry; Komdeur, Jan; Richardson, David S

2016-07-13

Introduced populations often lose the parasites they carried in their native range, but little is known about which processes may cause parasite loss during host movement. Conservation-driven translocations could provide an opportunity to identify the mechanisms involved. Using 3,888 blood samples collected over 22 years, we investigated parasite prevalence in populations of Seychelles warblers (Acrocephalus sechellensis) after individuals were translocated from Cousin Island to four new islands (Aride, Cousine, Denis and Frégate). Only a single parasite (Haemoproteus nucleocondensus) was detected on Cousin (prevalence = 52%). This parasite persisted on Cousine (prevalence = 41%), but no infection was found in individuals hatched on Aride, Denis or Frégate. It is not known whether the parasite ever arrived on Aride, but it has not been detected there despite 20 years of post-translocation sampling. We confirmed that individuals translocated to Denis and Frégate were infected, with initial prevalence similar to Cousin. Over time, prevalence decreased on Denis and Frégate until the parasite was not found on Denis two years after translocation, and was approaching zero prevalence on Frégate. The loss (Denis) or decline (Frégate) of H. nucleocondensus, despite successful establishment of infected hosts, must be due to factors affecting parasite transmission on these islands.

A universal ankle-foot prosthesis emulator for human locomotion experiments.

PubMed

Caputo, Joshua M; Collins, Steven H

2014-03-01

Robotic prostheses have the potential to significantly improve mobility for people with lower-limb amputation. Humans exhibit complex responses to mechanical interactions with these devices, however, and computational models are not yet able to predict such responses meaningfully. Experiments therefore play a critical role in development, but have been limited by the use of product-like prototypes, each requiring years of development and specialized for a narrow range of functions. Here we describe a robotic ankle-foot prosthesis system that enables rapid exploration of a wide range of dynamical behaviors in experiments with human subjects. This emulator comprises powerful off-board motor and control hardware, a flexible Bowden cable tether, and a lightweight instrumented prosthesis, resulting in a combination of low mass worn by the human (0.96 kg) and high mechatronic performance compared to prior platforms. Benchtop tests demonstrated closed-loop torque bandwidth of 17 Hz, peak torque of 175 Nm, and peak power of 1.0 kW. Tests with an anthropomorphic pendulum "leg" demonstrated low interference from the tether, less than 1 Nm about the hip. This combination of low worn mass, high bandwidth, high torque, and unrestricted movement makes the platform exceptionally versatile. To demonstrate suitability for human experiments, we performed preliminary tests in which a subject with unilateral transtibial amputation walked on a treadmill at 1.25 ms-1 while the prosthesis behaved in various ways. These tests revealed low torque tracking error (RMS error of 2.8 Nm) and the capacity to systematically vary work production or absorption across a broad range (from -5 to 21 J per step). These results support the use of robotic emulators during early stage assessment of proposed device functionalities and for scientific study of fundamental aspects of human-robot interaction. The design of simple, alternate end-effectors would enable studies at other joints or with

A Structured Microprogram Set for the SUMC Computer to Emulate the IBM System/360, Model 50

NASA Technical Reports Server (NTRS)

Gimenez, Cesar R.

1975-01-01

Similarities between regular and structured microprogramming were examined. An explanation of machine branching architecture (particularly in the SUMC computer), required for ease of structured microprogram implementation is presented. Implementation of a structured microprogram set in the SUMC to emulate the IBM System/360 is described and a comparison is made between the structured set with a nonstructured set previously written for the SUMC.

Appendices to the user's manual for a computer program for the emulation/simulation of a space station environmental control and life support system

NASA Technical Reports Server (NTRS)

Yanosy, James L.

1988-01-01

A user's Manual for the Emulation Simulation Computer Model was published previously. The model consisted of a detailed model (emulation) of a SAWD CO2 removal subsystem which operated with much less detailed (simulation) models of a cabin, crew, and condensing and sensible heat exchangers. The purpose was to explore the utility of such an emulation/simulation combination in the design, development, and test of a piece of ARS hardware - SAWD. Extensions to this original effort are presented. The first extension is an update of the model to reflect changes in the SAWD control logic which resulted from the test. In addition, slight changes were also made to the SAWD model to permit restarting and to improve the iteration technique. The second extension is the development of simulation models for more pieces of air and water processing equipment. Models are presented for: EDC, Molecular Sieve, Bosch, Sabatier, a new condensing heat exchanger, SPE, SFWES, Catalytic Oxidizer, and multifiltration. The third extension is to create two system simulations using these models. The first system presented consists of one air and one water processing system, the second a potential Space Station air revitalization system.

Emulating RRTMG Radiation with Deep Neural Networks for the Accelerated Model for Climate and Energy

NASA Astrophysics Data System (ADS)

Pal, A.; Norman, M. R.

2017-12-01

The RRTMG radiation scheme in the Accelerated Model for Climate and Energy Multi-scale Model Framework (ACME-MMF), is a bottleneck and consumes approximately 50% of the computational time. To simulate a case using RRTMG radiation scheme in ACME-MMF with high throughput and high resolution will therefore require a speed-up of this calculation while retaining physical fidelity. In this study, RRTMG radiation is emulated with Deep Neural Networks (DNNs). The first step towards this goal is to run a case with ACME-MMF and generate input data sets for the DNNs. A principal component analysis of these input data sets are carried out. Artificial data sets are created using the previous data sets to cover a wider space. These artificial data sets are used in a standalone RRTMG radiation scheme to generate outputs in a cost effective manner. These input-output pairs are used to train multiple architectures DNNs(1). Another DNN(2) is trained using the inputs to predict the error. A reverse emulation is trained to map the output to input. An error controlled code is developed with the two DNNs (1 and 2) and will determine when/if the original parameterization needs to be used.

Utility of Emulation and Simulation Computer Modeling of Space Station Environmental Control and Life Support Systems

NASA Technical Reports Server (NTRS)

Yanosy, James L.

1988-01-01

Over the years, computer modeling has been used extensively in many disciplines to solve engineering problems. A set of computer program tools is proposed to assist the engineer in the various phases of the Space Station program from technology selection through flight operations. The development and application of emulation and simulation transient performance modeling tools for life support systems are examined. The results of the development and the demonstration of the utility of three computer models are presented. The first model is a detailed computer model (emulation) of a solid amine water desorbed (SAWD) CO2 removal subsystem combined with much less detailed models (simulations) of a cabin, crew, and heat exchangers. This model was used in parallel with the hardware design and test of this CO2 removal subsystem. The second model is a simulation of an air revitalization system combined with a wastewater processing system to demonstrate the capabilities to study subsystem integration. The third model is that of a Space Station total air revitalization system. The station configuration consists of a habitat module, a lab module, two crews, and four connecting nodes.

Organic blueberry production systems: management of plant nutrition, irrigation requirements, and weeds

USDA-ARS?s Scientific Manuscript database

A long-term systems trial was established to evaluate management practices for organic production of northern highbush blueberry (Vaccinium corymbosum L.). The factorial experiment included two planting bed treatments (flat and raised beds), source and rate of fertilizer (feather meal and fish emuls...

A before-after control-impact assessment to understand the potential impacts of highway construction noise and activity on an endangered songbird.

PubMed

Long, Ashley M; Colón, Melanie R; Bosman, Jessica L; Robinson, Dianne H; Pruett, Hannah L; McFarland, Tiffany M; Mathewson, Heather A; Szewczak, Joseph M; Newnam, J Cal; Morrison, Michael L

2017-01-01

Anthropogenic noise associated with highway construction and operation can have individual- and population-level consequences for wildlife (e.g., reduced densities, decreased reproductive success, behavioral changes). We used a before-after control-impact study design to examine the potential impacts of highway construction and traffic noise on endangered golden-cheeked warblers ( Setophaga chrysoparia ; hereafter warbler) in urban Texas. We mapped and monitored warbler territories before (2009-2011), during (2012-2013), and after (2014) highway construction at three study sites: a treatment site exposed to highway construction and traffic noise, a control site exposed only to traffic noise, and a second control site exposed to neither highway construction or traffic noise. We measured noise levels at varying distances from the highway at sites exposed to construction and traffic noise. We examined how highway construction and traffic noise influenced warbler territory density, territory placement, productivity, and song characteristics. In addition, we conducted a playback experiment within study sites to evaluate acute behavioral responses to highway construction noises. Noise decreased with increasing distance from the highways. However, noise did not differ between the construction and traffic noise sites or across time. Warbler territory density increased over time at all study sites, and we found no differences in warbler territory placement, productivity, behavior, or song characteristics that we can attribute to highway construction or traffic noise. As such, we found no evidence to suggest that highway construction or traffic noise had a negative effect on warblers during our study. Because human population growth will require recurring improvements to transportation infrastructure, understanding wildlife responses to anthropogenic noise associated with the construction and operation of roads is essential for effective management and recovery of

Emulating DC constant power load: a robust sliding mode control approach

NASA Astrophysics Data System (ADS)

Singh, Suresh; Fulwani, Deepak; Kumar, Vinod

2017-09-01

This article presents emulation of a programmable power electronic, constant power load (CPL) using a dc/dc step-up (boost) converter. The converter is controlled by a robust sliding mode controller (SMC). A novel switching surface is proposed to ensure a required power sunk by the converter. The proposed dc CPL is simple in design, has fast dynamic response and high accuracy, and offers an inexpensive alternative to study converters for cascaded dc distribution power system applications. Furthermore, the proposed CPL is sufficiently robust against the input voltage variations. A laboratory prototype of the proposed dc CPL has been developed and validated with SMC realised through OPAL-RT platform. The capability of the proposed dc CPL is confirmed via experimentations in varied scenarios.

Aerodynamic consequences of wing morphing during emulated take-off and gliding in birds.

PubMed

Klaassen van Oorschot, Brett; Mistick, Emily A; Tobalske, Bret W

2016-10-01

Birds morph their wings during a single wingbeat, across flight speeds and among flight modes. Such morphing may allow them to maximize aerodynamic performance, but this assumption remains largely untested. We tested the aerodynamic performance of swept and extended wing postures of 13 raptor species in three families (Accipitridae, Falconidae and Strigidae) using a propeller model to emulate mid-downstroke of flapping during take-off and a wind tunnel to emulate gliding. Based on previous research, we hypothesized that (1) during flapping, wing posture would not affect maximum ratios of vertical and horizontal force coefficients (C V :C H ), and that (2) extended wings would have higher maximum C V :C H when gliding. Contrary to each hypothesis, during flapping, extended wings had, on average, 31% higher maximum C V :C H ratios and 23% higher C V than swept wings across all biologically relevant attack angles (α), and, during gliding, maximum C V :C H ratios were similar for the two postures. Swept wings had 11% higher C V than extended wings in gliding flight, suggesting flow conditions around these flexed raptor wings may be different from those in previous studies of swifts (Apodidae). Phylogenetic affiliation was a poor predictor of wing performance, due in part to high intrafamilial variation. Mass was only significantly correlated with extended wing performance during gliding. We conclude that wing shape has a greater effect on force per unit wing area during flapping at low advance ratio, such as take-off, than during gliding. © 2016. Published by The Company of Biologists Ltd.

Presence-nonpresence surveys of golden-cheeked warblers: detection, occupancy and survey effort

USGS Publications Warehouse

Watson, C.A.; Weckerly, F.W.; Hatfield, J.S.; Farquhar, C.C.; Williamson, P.S.

2008-01-01

Surveys to detect the presence or absence of endangered species may not consistently cover an area, account for imperfect detection or consider that detection and species presence at sample units may change within a survey season. We evaluated a detection?nondetection survey method for the federally endangered golden-cheeked warbler (GCWA) Dendroica chrysoparia. Three study areas were selected across the breeding range of GCWA in central Texas. Within each area, 28-36 detection stations were placed 200 m apart. Each detection station was surveyed nine times during the breeding season in 2 consecutive years. Surveyors remained up to 8 min at each detection station recording GCWA detected by sight or sound. To assess the potential influence of environmental covariates (e.g. slope, aspect, canopy cover, study area) on detection and occupancy and possible changes in occupancy and detection probabilities within breeding seasons, 30 models were analyzed. Using information-theoretic model selection procedures, we found that detection probabilities and occupancy varied among study areas and within breeding seasons. Detection probabilities ranged from 0.20 to 0.80 and occupancy ranged from 0.56 to 0.95. Because study areas with high detection probabilities had high occupancy, a conservative survey effort (erred towards too much surveying) was estimated using the lowest detection probability. We determined that nine surveys of 35 stations were needed to have estimates of occupancy with coefficients of variation <20%. Our survey evaluation evidently captured the key environmental variable that influenced bird detection (GCWA density) and accommodated the changes in GCWA distribution throughout the breeding season.

Toll-like receptor variation in the bottlenecked population of the Seychelles warbler: computer simulations see the 'ghost of selection past' and quantify the 'drift debt'.

PubMed

Gilroy, D L; Phillips, K P; Richardson, D S; van Oosterhout, C

2017-07-01

Balancing selection can maintain immunogenetic variation within host populations, but detecting its signal in a postbottlenecked population is challenging due to the potentially overriding effects of drift. Toll-like receptor genes (TLRs) play a fundamental role in vertebrate immune defence and are predicted to be under balancing selection. We previously characterized variation at TLR loci in the Seychelles warbler (Acrocephalus sechellensis), an endemic passerine that has undergone a historical bottleneck. Five of seven TLR loci were polymorphic, which is in sharp contrast to the low genomewide variation observed. However, standard population genetic statistical methods failed to detect a contemporary signature of selection at any TLR locus. We examined whether the observed TLR polymorphism could be explained by neutral evolution, simulating the population's demography in the software DIYABC. This showed that the posterior distributions of mutation rates had to be unrealistically high to explain the observed genetic variation. We then conducted simulations with an agent-based model using typical values for the mutation rate, which indicated that weak balancing selection has acted on the three TLR genes. The model was able to detect evidence of past selection elevating TLR polymorphism in the prebottleneck populations, but was unable to discern any effects of balancing selection in the contemporary population. Our results show drift is the overriding evolutionary force that has shaped TLR variation in the contemporary Seychelles warbler population, and the observed TLR polymorphisms might be merely the 'ghost of selection past'. Forecast models predict immunogenetic variation in this species will continue to be eroded in the absence of contemporary balancing selection. Such 'drift debt' occurs when a gene pool has not yet reached its new equilibrium level of polymorphism, and this loss could be an important threat to many recently bottlenecked populations. © 2017

Appendices to the model description document for a computer program for the emulation/simulation of a space station environmental control and life support system

NASA Technical Reports Server (NTRS)

Yanosy, James L.

1988-01-01

A Model Description Document for the Emulation Simulation Computer Model was already published. The model consisted of a detailed model (emulation) of a SAWD CO2 removal subsystem which operated with much less detailed (simulation) models of a cabin, crew, and condensing and sensible heat exchangers. The purpose was to explore the utility of such an emulation simulation combination in the design, development, and test of a piece of ARS hardware, SAWD. Extensions to this original effort are presented. The first extension is an update of the model to reflect changes in the SAWD control logic which resulted from test. Also, slight changes were also made to the SAWD model to permit restarting and to improve the iteration technique. The second extension is the development of simulation models for more pieces of air and water processing equipment. Models are presented for: EDC, Molecular Sieve, Bosch, Sabatier, a new condensing heat exchanger, SPE, SFWES, Catalytic Oxidizer, and multifiltration. The third extension is to create two system simulations using these models. The first system presented consists of one air and one water processing system. The second consists of a potential air revitalization system.

The impact of conservation-driven translocations on blood parasite prevalence in the Seychelles warbler

PubMed Central

Fairfield, Eleanor A.; Hutchings, Kimberly; Gilroy, Danielle L.; Kingma, Sjouke A.; Burke, Terry; Komdeur, Jan; Richardson, David S.

2016-01-01

Introduced populations often lose the parasites they carried in their native range, but little is known about which processes may cause parasite loss during host movement. Conservation-driven translocations could provide an opportunity to identify the mechanisms involved. Using 3,888 blood samples collected over 22 years, we investigated parasite prevalence in populations of Seychelles warblers (Acrocephalus sechellensis) after individuals were translocated from Cousin Island to four new islands (Aride, Cousine, Denis and Frégate). Only a single parasite (Haemoproteus nucleocondensus) was detected on Cousin (prevalence = 52%). This parasite persisted on Cousine (prevalence = 41%), but no infection was found in individuals hatched on Aride, Denis or Frégate. It is not known whether the parasite ever arrived on Aride, but it has not been detected there despite 20 years of post-translocation sampling. We confirmed that individuals translocated to Denis and Frégate were infected, with initial prevalence similar to Cousin. Over time, prevalence decreased on Denis and Frégate until the parasite was not found on Denis two years after translocation, and was approaching zero prevalence on Frégate. The loss (Denis) or decline (Frégate) of H. nucleocondensus, despite successful establishment of infected hosts, must be due to factors affecting parasite transmission on these islands. PMID:27405249

Emulating natural disturbance regimes: an emerging approach for sustainable forest management

Treesearch

M. North; W Keeton

2008-01-01

Sustainable forest management integrates ecological, social, and economic objectives. To achieve the former, researchers and practitioners are modifying silvicultural practices based on concepts from successional and landscape ecology to provide a broader array of ecosystem functions than is associated with conventional approaches. One...

A Robotic Fish to Emulate the Fast-Start

NASA Astrophysics Data System (ADS)

Currier, Todd; Ma, Ganzhong; Modarres-Sadeghi, Yahya

2017-11-01

An experimental study is conducted on a robotic fish designed to emulate the fast-start response. The fish body is constructed of 3D printed ribs and a light spring steel spine. The body is actuated using a series of pressured pistons. A total of four pistons are supplied with pressure through lightweight high pressure service lines. The source of pressure is carbon dioxide with a 700 psi peak operating pressure resulting in a body response that can cycle a c-start maneuver in milliseconds. The motion of the fish is precisely controlled through the use of solenoids with a control signal produced by a programmable microprocessor. The fish is constrained in all translational degrees of freedom but allowed to rotate about a vertical axis. The influence of the point of rotation is studied with different mounting points along the length of the head of the fish. The forces are measured in two perpendicular in-plane directions. A high speed camera is used to capture the response of the fish and the corresponding flow around it. Comparison is made with the kinematics observed in live fish.

Design and Modeling of a Test Bench for Dual-Motor Electric Drive Tracked Vehicles Based on a Dynamic Load Emulation Method.

PubMed

Wang, Zhe; Lv, Haoliang; Zhou, Xiaojun; Chen, Zhaomeng; Yang, Yong

2018-06-21

Dual-motor Electric Drive Tracked Vehicles (DDTVs) have attracted increasing attention due to their high transmission efficiency and economical fuel consumption. A test bench for the development and validation of new DDTV technologies is necessary and urgent. How to load the vehicle on a DDTV test bench exactly the same as on a real road is a crucial issue when designing the bench. This paper proposes a novel dynamic load emulation method to address this problem. The method adopts dual dynamometers to simulate both the road load and the inertia load that are imposed on the dual independent drive systems. The vehicle’s total inertia equivalent to the drive wheels is calculated with separate consideration of vehicle body, tracks and road wheels to obtain a more accurate inertia load. A speed tracking control strategy with feedforward compensation is implemented to control the dual dynamometers, so as to make the real-time dynamic load emulation possible. Additionally, a MATLAB/Simulink model of the test bench is built based on a dynamics analysis of the platform. Experiments are finally carried out on this test bench under different test conditions. The outcomes show that the proposed load emulation method is effective, and has good robustness and adaptability to complex driving conditions. Besides, the accuracy of the established test bench model is also demonstrated by comparing the results obtained from the simulation model and experiments.

Synchronous parallel system for emulation and discrete event simulation

NASA Technical Reports Server (NTRS)

Steinman, Jeffrey S. (Inventor)

1992-01-01

A synchronous parallel system for emulation and discrete event simulation having parallel nodes responds to received messages at each node by generating event objects having individual time stamps, stores only the changes to state variables of the simulation object attributable to the event object, and produces corresponding messages. The system refrains from transmitting the messages and changing the state variables while it determines whether the changes are superseded, and then stores the unchanged state variables in the event object for later restoral to the simulation object if called for. This determination preferably includes sensing the time stamp of each new event object and determining which new event object has the earliest time stamp as the local event horizon, determining the earliest local event horizon of the nodes as the global event horizon, and ignoring the events whose time stamps are less than the global event horizon. Host processing between the system and external terminals enables such a terminal to query, monitor, command or participate with a simulation object during the simulation process.

Synchronous Parallel System for Emulation and Discrete Event Simulation

NASA Technical Reports Server (NTRS)

Steinman, Jeffrey S. (Inventor)

2001-01-01

A synchronous parallel system for emulation and discrete event simulation having parallel nodes responds to received messages at each node by generating event objects having individual time stamps, stores only the changes to the state variables of the simulation object attributable to the event object and produces corresponding messages. The system refrains from transmitting the messages and changing the state variables while it determines whether the changes are superseded, and then stores the unchanged state variables in the event object for later restoral to the simulation object if called for. This determination preferably includes sensing the time stamp of each new event object and determining which new event object has the earliest time stamp as the local event horizon, determining the earliest local event horizon of the nodes as the global event horizon, and ignoring events whose time stamps are less than the global event horizon. Host processing between the system and external terminals enables such a terminal to query, monitor, command or participate with a simulation object during the simulation process.

Conjunctively optimizing flash flood control and water quality in urban water reservoirs by model predictive control and dynamic emulation

NASA Astrophysics Data System (ADS)

Galelli, Stefano; Goedbloed, Albert; Schmitter, Petra; Castelletti, Andrea

2014-05-01

Urban water reservoirs are a viable adaptation option to account for increasing drinking water demand of urbanized areas as they allow storage and re-use of water that is normally lost. In addition, the direct availability of freshwater reduces pumping costs and diversifies the portfolios of drinking water supply. Yet, these benefits have an associated twofold cost. Firstly, the presence of large, impervious areas increases the hydraulic efficiency of urban catchments, with short time of concentration, increased runoff rates, losses of infiltration and baseflow, and higher risk of flash floods. Secondly, the high concentration of nutrients and sediments characterizing urban discharges is likely to cause water quality problems. In this study we propose a new control scheme combining Model Predictive Control (MPC), hydro-meteorological forecasts and dynamic model emulation to design real-time operating policies that conjunctively optimize water quantity and quality targets. The main advantage of this scheme stands in its capability of exploiting real-time hydro-meteorological forecasts, which are crucial in such fast-varying systems. In addition, the reduced computational requests of the MPC scheme allows coupling it with dynamic emulators of water quality processes. The approach is demonstrated on Marina Reservoir, a multi-purpose reservoir located in the heart of Singapore and characterized by a large, highly urbanized catchment with a short (i.e. approximately one hour) time of concentration. Results show that the MPC scheme, coupled with a water quality emulator, provides a good compromise between different operating objectives, namely flood risk reduction, drinking water supply and salinity control. Finally, the scheme is used to assess the effect of source control measures (e.g. green roofs) aimed at restoring the natural hydrological regime of Marina Reservoir catchment.

Does seasonality drive spatial patterns in demography? Variation in survival in African reed warblers Acrocephalus baeticatus across southern Africa does not reflect global patterns

PubMed Central

Jansen, Dorine YM; Abadi, Fitsum; Harebottle, Doug; Altwegg, Res

2014-01-01

Among birds, northern temperate species generally have larger clutches, shorter development periods and lower adult survival than similarly-sized southern and tropical species. Even though this global pattern is well accepted, the driving mechanism is still not fully understood. The main theories are founded on the differing environmental seasonality of these zones (higher seasonality in the North). These patterns arise in cross-species comparisons, but we hypothesized that the same patterns should arise among populations within a species if different types of seasonality select for different life histories. Few studies have examined this. We estimated survival of an azonal habitat specialist, the African reed warbler, across the environmentally diverse African subcontinent, and related survival to latitude and to the seasonality of the different environments of their breeding habitats. Data (1998–2010) collected through a public ringing scheme were analyzed with hierarchical capture-mark-recapture models to determine resident adult survival and its spatial variance across sixteen vegetation units spread across four biomes. The models were defined as state-space multi-state models to account for transience and implemented in a Bayesian framework. We did not find a latitudinal trend in survival or a clear link between seasonality and survival. Spatial variation in survival was substantial across the sixteen sites (spatial standard deviation of the logit mean survival: 0.70, 95% credible interval (CRI): 0.33–1.27). Mean site survival ranged from 0.49 (95% CRI: 0.18–0.80) to 0.83 (95% CRI: 0.62–0.97) with an overall mean of 0.67 (95% CRI: 0.47–0.85). A hierarchical modeling approach enabled us to estimate spatial variation in survival of the African reed warbler across the African subcontinent from sparse data. Although we could not confirm the global pattern of higher survival in less seasonal environments, our findings from a poorly studied region

Parallel VLSI architecture emulation and the organization of APSA/MPP

NASA Technical Reports Server (NTRS)

Odonnell, John T.

1987-01-01

The Applicative Programming System Architecture (APSA) combines an applicative language interpreter with a novel parallel computer architecture that is well suited for Very Large Scale Integration (VLSI) implementation. The Massively Parallel Processor (MPP) can simulate VLSI circuits by allocating one processing element in its square array to an area on a square VLSI chip. As long as there are not too many long data paths, the MPP can simulate a VLSI clock cycle very rapidly. The APSA circuit contains a binary tree with a few long paths and many short ones. A skewed H-tree layout allows every processing element to simulate a leaf cell and up to four tree nodes, with no loss in parallelism. Emulation of a key APSA algorithm on the MPP resulted in performance 16,000 times faster than a Vax. This speed will make it possible for the APSA language interpreter to run fast enough to support research in parallel list processing algorithms.

Breeding season concerns and response to forest management: Can forest management produce more breeding birds? Ornitologia Neotropical

Treesearch

J.L. Larkin; P.B. Wood; T.J. Boves; J. Sheehan; D.A. Buehler

2012-01-01

Cerulean Warblers (Setophaga cerulea), one of the fastest declining avian species in North America, are associated with heterogeneous canopies in mature hardwood forests. However, the age of most second and third-growth forests in eastern North American is not sufficient for natural tree mortality to maintain structurally diverse canopies. Previous research suggests...

Emulation and Sensitivity Analysis of the Community Multiscale Air Quality Model for a UK Ozone Pollution Episode.

PubMed

Beddows, Andrew V; Kitwiroon, Nutthida; Williams, Martin L; Beevers, Sean D

2017-06-06

Gaussian process emulation techniques have been used with the Community Multiscale Air Quality model, simulating the effects of input uncertainties on ozone and NO 2 output, to allow robust global sensitivity analysis (SA). A screening process ranked the effect of perturbations in 223 inputs, isolating the 30 most influential from emissions, boundary conditions (BCs), and reaction rates. Community Multiscale Air Quality (CMAQ) simulations of a July 2006 ozone pollution episode in the UK were made with input values for these variables plus ozone dry deposition velocity chosen according to a 576 point Latin hypercube design. Emulators trained on the output of these runs were used in variance-based SA of the model output to input uncertainties. Performing these analyses for every hour of a 21 day period spanning the episode and several days on either side allowed the results to be presented as a time series of sensitivity coefficients, showing how the influence of different input uncertainties changed during the episode. This is one of the most complex models to which these methods have been applied, and here, they reveal detailed spatiotemporal patterns of model sensitivities, with NO and isoprene emissions, NO 2 photolysis, ozone BCs, and deposition velocity being among the most influential input uncertainties.

On geographic barriers and Pleistocene glaciations: Tracing the diversification of the Russet-crowned Warbler (Myiothlypis coronata) along the Andes

PubMed Central

2018-01-01

We studied the phylogeography and plumage variation of the Russet-crowned Warbler (Myiothlypis coronata), from Venezuela to Bolivia, with focus on populations from Ecuador and northern Peru. We analyzed sequences of mitochondrial and nuclear genes, geographic distributions, as well as photographs of specimens deposited at museum collections. Phylogenetic analyses identified three major lineages formed by populations from: Venezuela and Colombia (M. c. regulus), Ecuador and northern Peru (M. elata, M. castaneiceps, M. orientalis, M. c. chapmani), and central Peru and Bolivia (M. c. coronata). We found further population structure within M. c. regulus and M. c. coronata, and population structure and complexity of plumage variation within the Ecuador-northern Peru lineage. Time-calibrated trees estimated that most intraspecific variation originated during the Pleistocene; however, this pattern may not be attributed to an increase in diversification rate during that period. We discuss these results in the context of the importance of geographic-ecological barriers in promoting lineage diversification along the Andes and put forward a preliminary taxonomic proposal for major lineages identified in this study. PMID:29522515

On geographic barriers and Pleistocene glaciations: Tracing the diversification of the Russet-crowned Warbler (Myiothlypis coronata) along the Andes.

PubMed

Prieto-Torres, David A; Cuervo, Andrés M; Bonaccorso, Elisa

2018-01-01

We studied the phylogeography and plumage variation of the Russet-crowned Warbler (Myiothlypis coronata), from Venezuela to Bolivia, with focus on populations from Ecuador and northern Peru. We analyzed sequences of mitochondrial and nuclear genes, geographic distributions, as well as photographs of specimens deposited at museum collections. Phylogenetic analyses identified three major lineages formed by populations from: Venezuela and Colombia (M. c. regulus), Ecuador and northern Peru (M. elata, M. castaneiceps, M. orientalis, M. c. chapmani), and central Peru and Bolivia (M. c. coronata). We found further population structure within M. c. regulus and M. c. coronata, and population structure and complexity of plumage variation within the Ecuador-northern Peru lineage. Time-calibrated trees estimated that most intraspecific variation originated during the Pleistocene; however, this pattern may not be attributed to an increase in diversification rate during that period. We discuss these results in the context of the importance of geographic-ecological barriers in promoting lineage diversification along the Andes and put forward a preliminary taxonomic proposal for major lineages identified in this study.

Hydrologic and water-quality data at Government Canyon State Natural Area, Bexar County, Texas, 2002-10

USGS Publications Warehouse

Banta, J. Ryan; Slattery, Richard N.

2012-01-01

The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Natural Resources Conservation Service, the Edwards Aquifer Authority, and the Texas Parks and Wildlife Department, collected rainfall, streamflow, evapotranspiration, and stormflow water-quality data at the Laurel Canyon Creek watershed, within the Government Canyon State Natural Area, Bexar County, Tex. The purpose of the data collection was to support evaluations of the effects of brush management conservation practices on components of the hydrologic budget and water quality. One component of brush management was to take endangered wildlife into consideration, specifically the golden-cheeked warbler (Dendroica chrysoparia). Much of the area that may have been considered for brush management was left intact to protect habitat for the golden-cheeked warbler. The area identified for brush management was approximately 10 percent of the study watershed. The hydrologic data presented here (2002–10) represent pre- and post-treatment periods, with brush management treatment occurring from winter 2006–07 to spring 2008.

Space Link Extension Protocol Emulation for High-Throughput, High-Latency Network Connections

NASA Technical Reports Server (NTRS)

Tchorowski, Nicole; Murawski, Robert

2014-01-01

New space missions require higher data rates and new protocols to meet these requirements. These high data rate space communication links push the limitations of not only the space communication links, but of the ground communication networks and protocols which forward user data to remote ground stations (GS) for transmission. The Consultative Committee for Space Data Systems, (CCSDS) Space Link Extension (SLE) standard protocol is one protocol that has been proposed for use by the NASA Space Network (SN) Ground Segment Sustainment (SGSS) program. New protocol implementations must be carefully tested to ensure that they provide the required functionality, especially because of the remote nature of spacecraft. The SLE protocol standard has been tested in the NASA Glenn Research Center's SCENIC Emulation Lab in order to observe its operation under realistic network delay conditions. More specifically, the delay between then NASA Integrated Services Network (NISN) and spacecraft has been emulated. The round trip time (RTT) delay for the continental NISN network has been shown to be up to 120ms; as such the SLE protocol was tested with network delays ranging from 0ms to 200ms. Both a base network condition and an SLE connection were tested with these RTT delays, and the reaction of both network tests to the delay conditions were recorded. Throughput for both of these links was set at 1.2Gbps. The results will show that, in the presence of realistic network delay, the SLE link throughput is significantly reduced while the base network throughput however remained at the 1.2Gbps specification. The decrease in SLE throughput has been attributed to the implementation's use of blocking calls. The decrease in throughput is not acceptable for high data rate links, as the link requires constant data a flow in order for spacecraft and ground radios to stay synchronized, unless significant data is queued a the ground station. In cases where queuing the data is not an option

Toward a nanoscience emulator with two dimensional atomic gases

NASA Astrophysics Data System (ADS)

Wang, Ping; Ma, Q.; Dutta, S.; Chen, Yong P.

2009-05-01

We report our experimental progress in constructing a cold atom apparatus for emulating phenomena in nanoscience using low dimensional atom gases. Our first experiments will be performed with a 2D ^87Rb Bose-Einstein condensate created in an optical lattice. Our compact vacuum system consists of two AR-coated glass cells --- a low vacuum magneto-optical trap (MOT) chamber and a high vacuum ``science chamber'', connected by a 15cm-long tube for differential pumping. We have used elliptically shaped cooling laser beams and magnet field coils to realize an elongated MOT in the first chamber, and transferred the atoms to a second MOT in the science chamber by a push laser beam. In the science chamber, a 50W, 1550nm single frequency erbium fiber laser is used to produce an optical dipole trap and optical lattice.In addition, controllable disorder can be introduced with laser speckle and inter-atomic interactions can be tuned by atomic density or Feshbach resonance. We plan to explore important phenomena in nanoscience, such as 2D disorder-induced conductor-insulator transition, quantum Hall effect and graphene-like physics in such a tunable 2D atomic gas in optical lattices.

Emulation of Physician Tasks in Eye-Tracked Virtual Reality for Remote Diagnosis of Neurodegenerative Disease.

PubMed

Orlosky, Jason; Itoh, Yuta; Ranchet, Maud; Kiyokawa, Kiyoshi; Morgan, John; Devos, Hannes

2017-04-01

For neurodegenerative conditions like Parkinson's disease, early and accurate diagnosis is still a difficult task. Evaluations can be time consuming, patients must often travel to metropolitan areas or different cities to see experts, and misdiagnosis can result in improper treatment. To date, only a handful of assistive or remote methods exist to help physicians evaluate patients with suspected neurological disease in a convenient and consistent way. In this paper, we present a low-cost VR interface designed to support evaluation and diagnosis of neurodegenerative disease and test its use in a clinical setting. Using a commercially available VR display with an infrared camera integrated into the lens, we have constructed a 3D virtual environment designed to emulate common tasks used to evaluate patients, such as fixating on a point, conducting smooth pursuit of an object, or executing saccades. These virtual tasks are designed to elicit eye movements commonly associated with neurodegenerative disease, such as abnormal saccades, square wave jerks, and ocular tremor. Next, we conducted experiments with 9 patients with a diagnosis of Parkinson's disease and 7 healthy controls to test the system's potential to emulate tasks for clinical diagnosis. We then applied eye tracking algorithms and image enhancement to the eye recordings taken during the experiment and conducted a short follow-up study with two physicians for evaluation. Results showed that our VR interface was able to elicit five common types of movements usable for evaluation, physicians were able to confirm three out of four abnormalities, and visualizations were rated as potentially useful for diagnosis.

A Voice-Detecting Sensor and a Scanning Keyboard Emulator to Support Word Writing by Two Boys with Extensive Motor Disabilities

ERIC Educational Resources Information Center

Lancioni, Giulio E.; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff; Green, Vanessa; Chiapparino, Claudia; Stasolla, Fabrizio; Oliva, Doretta

2009-01-01

The present study assessed the use of a voice-detecting sensor interfaced with a scanning keyboard emulator to allow two boys with extensive motor disabilities to write. Specifically, the study (a) compared the effects of the voice-detecting sensor with those of a familiar pressure sensor on the boys' writing time, (b) checked which of the sensors…

Emulating atmosphere-ocean and carbon cycle models with a simpler model, MAGICC6 - Part 2: Applications

NASA Astrophysics Data System (ADS)

Meinshausen, M.; Wigley, T. M. L.; Raper, S. C. B.

2011-02-01

Intercomparisons of coupled atmosphere-ocean general circulation models (AOGCMs) and carbon cycle models are important for galvanizing our current scientific knowledge to project future climate. Interpreting such intercomparisons faces major challenges, not least because different models have been forced with different sets of forcing agents. Here, we show how an emulation approach with MAGICC6 can address such problems. In a companion paper (Meinshausen et al., 2011a), we show how the lower complexity carbon cycle-climate model MAGICC6 can be calibrated to emulate, with considerable accuracy, globally aggregated characteristics of these more complex models. Building on that, we examine here the Coupled Model Intercomparison Project's Phase 3 results (CMIP3). If forcing agents missed by individual AOGCMs in CMIP3 are considered, this reduces ensemble average temperature change from pre-industrial times to 2100 under SRES A1B by 0.4 °C. Differences in the results from the 1980 to 1999 base period (as reported in IPCC AR4) to 2100 are negligible, however, although there are some differences in the trajectories over the 21st century. In a second part of this study, we consider the new RCP scenarios that are to be investigated under the forthcoming CMIP5 intercomparison for the IPCC Fifth Assessment Report. For the highest scenario, RCP8.5, relative to pre-industrial levels, we project a median warming of around 4.6 °C by 2100 and more than 7 °C by 2300. For the lowest RCP scenario, RCP3-PD, the corresponding warming is around 1.5 °C by 2100, decreasing to around 1.1 °C by 2300 based on our AOGCM and carbon cycle model emulations. Implied cumulative CO2 emissions over the 21st century for RCP8.5 and RCP3-PD are 1881 GtC (1697 to 2034 GtC, 80% uncertainty range) and 381 GtC (334 to 488 GtC), when prescribing CO2 concentrations and accounting for uncertainty in the carbon cycle. Lastly, we assess the reasons why a previous MAGICC version (4.2) used in IPCC AR4 gave

Emulating Many-Body Localization with a Superconducting Quantum Processor

NASA Astrophysics Data System (ADS)

Xu, Kai; Chen, Jin-Jun; Zeng, Yu; Zhang, Yu-Ran; Song, Chao; Liu, Wuxin; Guo, Qiujiang; Zhang, Pengfei; Xu, Da; Deng, Hui; Huang, Keqiang; Wang, H.; Zhu, Xiaobo; Zheng, Dongning; Fan, Heng

2018-02-01

The law of statistical physics dictates that generic closed quantum many-body systems initialized in nonequilibrium will thermalize under their own dynamics. However, the emergence of many-body localization (MBL) owing to the interplay between interaction and disorder, which is in stark contrast to Anderson localization, which only addresses noninteracting particles in the presence of disorder, greatly challenges this concept, because it prevents the systems from evolving to the ergodic thermalized state. One critical evidence of MBL is the long-time logarithmic growth of entanglement entropy, and a direct observation of it is still elusive due to the experimental challenges in multiqubit single-shot measurement and quantum state tomography. Here we present an experiment fully emulating the MBL dynamics with a 10-qubit superconducting quantum processor, which represents a spin-1 /2 X Y model featuring programmable disorder and long-range spin-spin interactions. We provide essential signatures of MBL, such as the imbalance due to the initial nonequilibrium, the violation of eigenstate thermalization hypothesis, and, more importantly, the direct evidence of the long-time logarithmic growth of entanglement entropy. Our results lay solid foundations for precisely simulating the intriguing physics of quantum many-body systems on the platform of large-scale multiqubit superconducting quantum processors.

Shared Governance and Organizational Commitment Reported by Enrollment Managers in the Council of Christian Colleges and Universities

ERIC Educational Resources Information Center

Jones, Don Wayne

2017-01-01

Many faith-based liberal arts institutions are tuition-dependent and are forced to compete with both public institutions as well as private for-profit colleges and universities to maintain student enrollment levels. Some faith-based institutions have adopted strategic enrollment management policies and procedures that emulate the best practices…

The impact of translocations on neutral and functional genetic diversity within and among populations of the Seychelles warbler.

PubMed

Wright, David J; Spurgin, Lewis G; Collar, Nigel J; Komdeur, Jan; Burke, Terry; Richardson, David S

2014-05-01

Translocations are an increasingly common tool in conservation. The maintenance of genetic diversity through translocation is critical for both the short- and long-term persistence of populations and species. However, the relative spatio-temporal impacts of translocations on neutral and functional genetic diversity, and how this affects genetic structure among the conserved populations overall, have received little investigation. We compared the impact of translocating different numbers of founders on both microsatellite and major histocompatibility complex (MHC) class I diversity over a 23-year period in the Seychelles warbler (Acrocephalus sechellensis). We found low and stable microsatellite and MHC diversity in the source population and evidence for only a limited loss of either type of diversity in the four new populations. However, we found evidence of significant, but low to moderate, genetic differentiation between populations, with those populations established with fewer founders clustering separately. Stochastic genetic capture (as opposed to subsequent drift) was the main determinant of translocated population diversity. Furthermore, a strong correlation between microsatellite and MHC differentiation suggested that neutral processes outweighed selection in shaping MHC diversity in the new populations. These data provide important insights into how to optimize the use of translocation as a conservation tool. © 2014 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

The impact of translocations on neutral and functional genetic diversity within and among populations of the Seychelles warbler

PubMed Central

Wright, David J; Spurgin, Lewis G; Collar, Nigel J; Komdeur, Jan; Burke, Terry; Richardson, David S

2014-01-01

Translocations are an increasingly common tool in conservation. The maintenance of genetic diversity through translocation is critical for both the short- and long-term persistence of populations and species. However, the relative spatio-temporal impacts of translocations on neutral and functional genetic diversity, and how this affects genetic structure among the conserved populations overall, have received little investigation. We compared the impact of translocating different numbers of founders on both microsatellite and major histocompatibility complex (MHC) class I diversity over a 23-year period in the Seychelles warbler (Acrocephalus sechellensis). We found low and stable microsatellite and MHC diversity in the source population and evidence for only a limited loss of either type of diversity in the four new populations. However, we found evidence of significant, but low to moderate, genetic differentiation between populations, with those populations established with fewer founders clustering separately. Stochastic genetic capture (as opposed to subsequent drift) was the main determinant of translocated population diversity. Furthermore, a strong correlation between microsatellite and MHC differentiation suggested that neutral processes outweighed selection in shaping MHC diversity in the new populations. These data provide important insights into how to optimize the use of translocation as a conservation tool. PMID:24689851

Imitation and Emulation by Dogs Using a Bidirectional Control Procedure

PubMed Central

Miller, Holly C.; Rayburn-Reeves, Rebecca; Zentall, Thomas R.

2009-01-01

A successful procedure for studying imitative behavior in non-humans is the bidirectional control procedure in which observers are exposed to a demonstrator that responds by moving a manipulandum in one of two different directions (e.g., left vs. right). Imitative learning is demonstrated when observers make the response in the direction that they observed it being made. This procedure controls for socially mediated effects (the mere presence of a demonstrator), stimulus enhancement (attention drawn to a manipulandum by its movement), and if an appropriate control is included, emulation (learning how the environment works). Recent research with dogs has found that dogs may not demonstrate imitative learning when the demonstrator is human. In the present research, we found that when odors were controlled for, dogs imitated the direction of a screen push demonstrated by another dog more than in a control condition in which they observed the screen move independently while another dog was present. Furthermore, we found that dogs would match the direction of screen push demonstrated by a human and they were equally likely to match the direction in which the screen moved independently while a human was present. PMID:18977419

A methodology to emulate and evaluate a productive virtual workstation

NASA Technical Reports Server (NTRS)

Krubsack, David; Haberman, David

1992-01-01

The Advanced Display and Computer Augmented Control (ADCACS) Program at ACT is sponsored by NASA Ames to investigate the broad field of technologies which must be combined to design a 'virtual' workstation for the Space Station Freedom. This program is progressing in several areas and resulted in the definition of requirements for a workstation. A unique combination of technologies at the ACT Laboratory have been networked to effectively create an experimental environment. This experimental environment allows the integration of nonconventional input devices with a high power graphics engine within the framework of an expert system shell which coordinates the heterogeneous inputs with the 'virtual' presentation. The flexibility of the workstation is evolved as experiments are designed and conducted to evaluate the condition descriptions and rule sets of the expert system shell and its effectiveness in driving the graphics engine. Workstation productivity has been defined by the achievable performance in the emulator of the calibrated 'sensitivity' of input devices, the graphics presentation, the possible optical enhancements to achieve a wide field of view color image and the flexibility of conditional descriptions in the expert system shell in adapting to prototype problems.

Emulating Host-Microbiome Ecosystem of Human Gastrointestinal Tract in Vitro.

PubMed

Park, Gun-Seok; Park, Min Hee; Shin, Woojung; Zhao, Connie; Sheikh, Sameer; Oh, So Jung; Kim, Hyun Jung

2017-06-01

The human gut microbiome performs prodigious physiological functions such as production of microbial metabolites, modulation of nutrient digestion and drug metabolism, control of immune system, and prevention of infection. Paradoxically, gut microbiome can also negatively orchestrate the host responses in diseases or chronic disorders, suggesting that the regulated and balanced host-gut microbiome crosstalk is a salient prerequisite in gastrointestinal physiology. To understand the pathophysiological role of host-microbiome crosstalk, it is critical to recreate in vivo relevant models of the host-gut microbiome ecosystem in human. However, controlling the multi-species microbial communities and their uncontrolled growth has remained a notable technical challenge. Furthermore, conventional two-dimensional (2D) or 3D culture systems do not recapitulate multicellular microarchitectures, mechanical dynamics, and tissue-specific functions. Here, we review recent advances and current pitfalls of in vitro and ex vivo models that display human GI functions. We also discuss how the disruptive technologies such as 3D organoids or a human organ-on-a-chip microphysiological system can contribute to better emulate host-gut microbiome crosstalks in health and disease. Finally, the medical and pharmaceutical significance of the gut microbiome-based personalized interventions is underlined as a future perspective.

A fault injection experiment using the AIRLAB Diagnostic Emulation Facility

NASA Technical Reports Server (NTRS)

Baker, Robert; Mangum, Scott; Scheper, Charlotte

1988-01-01

The preparation for, conduct of, and results of a simulation based fault injection experiment conducted using the AIRLAB Diagnostic Emulation facilities is described. An objective of this experiment was to determine the effectiveness of the diagnostic self-test sequences used to uncover latent faults in a logic network providing the key fault tolerance features for a flight control computer. Another objective was to develop methods, tools, and techniques for conducting the experiment. More than 1600 faults were injected into a logic gate level model of the Data Communicator/Interstage (C/I). For each fault injected, diagnostic self-test sequences consisting of over 300 test vectors were supplied to the C/I model as inputs. For each test vector within a test sequence, the outputs from the C/I model were compared to the outputs of a fault free C/I. If the outputs differed, the fault was considered detectable for the given test vector. These results were then analyzed to determine the effectiveness of some test sequences. The results established coverage of selt-test diagnostics, identified areas in the C/I logic where the tests did not locate faults, and suggest fault latency reduction opportunities.

Comparative issues in aviation and surgical crew resource management: (1) are we too solution focused?

PubMed

Hunt, Graham J F; Callaghan, Kathleen S N

2008-08-01

Although the published work in health care increasingly promotes aviation as a high-reliability industry to be emulated, there is little empirical research to justify equating the dynamics of health care's operating environment with that of aviation. This article examines some of the potential key areas of difference between the two professional groups with respect to crew resource management. The risks of implementing crew resource management training in health care without an evidential basis are discussed.

Dynamics of parasitemia of malaria parasites in a naturally and experimentally infected migratory songbird, the great reed warbler Acrocephalus arundinaceus.

PubMed

Zehtindjiev, Pavel; Ilieva, Mihaela; Westerdahl, Helena; Hansson, Bengt; Valkiūnas, Gediminas; Bensch, Staffan

2008-05-01

Little is known about the development of infection of malaria parasites of the genus Plasmodium in wild birds. We used qPCR, targeting specific mitochondrial lineages of Plasmodium ashfordi (GRW2) and Plasmodium relictum (GRW4), to monitor changes in intensities of parasitemia in captive great reed warblers Acrocephalus arundinaceus from summer to spring. The study involved both naturally infected adults and experimentally infected juveniles. The experiment demonstrated that P. ashfordi and P. relictum lineages differ substantially in several life-history traits (e.g. prepatent period and dynamics of parasitemia) and that individual hosts show substantial differences in responses to these infections. The intensity of parasitemia of lineages in mixed infections co-varied positively, suggesting a control mechanism by the host that is general across the parasite lineages. The intensity of parasitemia for individual hosts was highly repeatable suggesting variation between the host individuals in their genetic or acquired control of the infections. In future studies, care must be taken to avoid mixed infections in wild caught donors, and when possible use mosquitoes for the experiments as inoculation of infectious blood ignores important initial stages of the contact between the bird and the parasite.

The Prospects of Whole Brain Emulation within the next Half- Century

NASA Astrophysics Data System (ADS)

Eth, Daniel; Foust, Juan-Carlos; Whale, Brandon

2013-12-01

Whole Brain Emulation (WBE), the theoretical technology of modeling a human brain in its entirety on a computer-thoughts, feelings, memories, and skills intact-is a staple of science fiction. Recently, proponents of WBE have suggested that it will be realized in the next few decades. In this paper, we investigate the plausibility of WBE being developed in the next 50 years (by 2063). We identify four essential requisite technologies: scanning the brain, translating the scan into a model, running the model on a computer, and simulating an environment and body. Additionally, we consider the cultural and social effects of WBE. We find the two most uncertain factors for WBE's future to be the development of advanced miniscule probes that can amass neural data in vivo and the degree to which the culture surrounding WBE becomes cooperative or competitive. We identify four plausible scenarios from these uncertainties and suggest the most likely scenario to be one in which WBE is realized, and the technology is used for moderately cooperative ends

Throwing the Uncertainty Toolbox at Antarctica: Multi-model Ensemble Simulation, Emulation and Bayesian Calibration of Marine Ice Sheet Instability

NASA Astrophysics Data System (ADS)

Edwards, T.

2015-12-01

Modelling Antarctic marine ice sheet instability (MISI) - the potential for sustained grounding line retreat along downsloping bedrock - is very challenging because high resolution at the grounding line is required for reliable simulation. Assessing modelling uncertainties is even more difficult, because such models are very computationally expensive, restricting the number of simulations that can be performed. Quantifying uncertainty in future Antarctic instability has therefore so far been limited. There are several ways to tackle this problem, including: Simulating a small domain, to reduce expense and allow the use of ensemble methods; Parameterising response of the grounding line to the onset of MISI, for the same reasons; Emulating the simulator with a statistical model, to explore the impacts of uncertainties more thoroughly; Substituting physical models with expert-elicited statistical distributions. Methods 2-4 require rigorous testing against observations and high resolution models to have confidence in their results. We use all four to examine the dependence of MISI in the Amundsen Sea Embayment (ASE) on uncertain model inputs, including bedrock topography, ice viscosity, basal friction, model structure (sliding law and treatment of grounding line migration) and MISI triggers (including basal melting and risk of ice shelf collapse). We compare simulations from a 3000 member ensemble with GRISLI (methods 2, 4) with a 284 member ensemble from BISICLES (method 1) and also use emulation (method 3). Results from the two ensembles show similarities, despite very different model structures and ensemble designs. Basal friction and topography have a large effect on the extent of grounding line retreat, and the sliding law strongly modifies sea level contributions through changes in the rate and extent of grounding line retreat and the rate of ice thinning. Over 50 years, MISI in the ASE gives up to 1.1 mm/year (95% quantile) SLE in GRISLI (calibrated with ASE

Management of Microcircuit Obsolescence in a Pre-Production ACAT-ID Missile Program

DTIC Science & Technology

2002-12-01

and Engineering Center ASIC Application Specific Integrated Circuit AVCOM Avionics Component Obsolescence Management BRU Battery Replaceable Unit...then just a paper qualification, e.g. Board or Battery Replaceable Unit ( BRU ) testing. 5 After-market Package The Die is Available and Can Be...Encapsulated Microcircuits (PEM), speed change, failure rate) 8 Emulation Manufacture or re-engineering of a FFF Replacement 9 CCA or BRU Redesign Board

Using Machine Learning as a fast emulator of physical processes within the Met Office's Unified Model

NASA Astrophysics Data System (ADS)

Prudden, R.; Arribas, A.; Tomlinson, J.; Robinson, N.

2017-12-01

The Unified Model is a numerical model of the atmosphere used at the UK Met Office (and numerous partner organisations including Korean Meteorological Agency, Australian Bureau of Meteorology and US Air Force) for both weather and climate applications.Especifically, dynamical models such as the Unified Model are now a central part of weather forecasting. Starting from basic physical laws, these models make it possible to predict events such as storms before they have even begun to form. The Unified Model can be simply described as having two components: one component solves the navier-stokes equations (usually referred to as the "dynamics"); the other solves relevant sub-grid physical processes (usually referred to as the "physics"). Running weather forecasts requires substantial computing resources - for example, the UK Met Office operates the largest operational High Performance Computer in Europe - and the cost of a typical simulation is spent roughly 50% in the "dynamics" and 50% in the "physics". Therefore there is a high incentive to reduce cost of weather forecasts and Machine Learning is a possible option because, once a machine learning model has been trained, it is often much faster to run than a full simulation. This is the motivation for a technique called model emulation, the idea being to build a fast statistical model which closely approximates a far more expensive simulation. In this paper we discuss the use of Machine Learning as an emulator to replace the "physics" component of the Unified Model. Various approaches and options will be presented and the implications for further model development, operational running of forecasting systems, development of data assimilation schemes, and development of ensemble prediction techniques will be discussed.

Insightful problem solving and emulation in brown capuchin monkeys.

PubMed

Renner, Elizabeth; Abramo, Allison M; Karen Hambright, M; Phillips, Kimberley A

2017-05-01

We investigated problem solving abilities of capuchin monkeys via the "floating object problem," a task in which the subject must use creative problem solving to retrieve a favored food item from the bottom of a clear tube. Some great apes have solved this problem by adding water to raise the object to a level at which it can be easily grabbed. We presented seven capuchins with the task over eight trials (four "dry" and four "wet"). None of the subjects solved the task, indicating that no capuchin demonstrated insightful problem solving under these experimental conditions. We then investigated whether capuchins would emulate a solution to the task. Seven subjects observed a human model solve the problem by pouring water from a cup into the tube, which brought the object to the top of the tube, allowing the subject to retrieve it. Subjects were then allowed to interact freely with an unfilled tube containing the object in the presence of water and objects that could be used to solve the task. While most subjects were unable to solve the task after viewing a demonstrator solve it, one subject did so, but in a unique way. Our results are consistent with some previous results in great ape species and indicate that capuchins do not spontaneously solve the floating object problem via insight.

Increased long-latency reflex activity as a sufficient explanation for childhood hypertonic dystonia: a neuromorphic emulation study

NASA Astrophysics Data System (ADS)

Sohn, Won J.; Niu, Chuanxin M.; Sanger, Terence D.

2015-06-01

Objective. Childhood dystonia is a movement disorder that interferes with daily movements and can have a devastating effect on quality of life for children and their families. Although injury to basal ganglia is associated with dystonia, the neurophysiological mechanisms leading to the clinical manifestations of dystonia are not understood. Previous work suggested that long-latency stretch reflex (LLSR) is hyperactive in children with hypertonia due to secondary dystonia. We hypothesize that abnormal activity in motor cortices may cause an increase in the LLSR leading to hypertonia. Approach. We modeled two possibilities of hyperactive LLSR by either creating a tonic involuntary drive to cortex, or increasing the synaptic gain in cortical neurons. Both models are emulated using programmable very-large-scale-integrated-circuit hardware to test their sufficiency for producing dystonic symptoms. The emulation includes a joint with two Hill-type muscles, realistic muscle spindles, and 2,304 Izhikevich-type spiking neurons. The muscles are regulated by a monosynaptic spinal pathway with 32 ms delay and a long-latency pathway with 64 ms loop-delay representing transcortical/supra-spinal connections. Main results. When the limb is passively stretched, both models produce involuntary resistance with increased antagonist EMG responses similar to human data; also the muscle relaxation is delayed similar to human data. Both models predict reduced range of motion in voluntary movements. Significance. Although our model is a highly simplified and limited representation of reflex pathways, it shows that increased activity of the LLSR is by itself sufficient to cause many of the features of hypertonic dystonia.

Development of HWIL Testing Capabilities for Satellite Target Emulation at AEDC

NASA Astrophysics Data System (ADS)

Lowry, H.; Crider, D.; Burns, J.; Thompson, R.; Goldsmith, G., II; Sholes, W.

Programs involved in Space Situational Awareness (SSA) need the capability to test satellite sensors in a Hardware-in-the-Loop (HWIL) environment. Testing in a ground system avoids the significant cost of on-orbit test targets and the resulting issues such as debris mitigation, and in-space testing implications. The space sensor test facilities at AEDC consist of cryo-vacuum chambers that have been developed to project simulated targets to air-borne, space-borne, and ballistic platforms. The 7V chamber performs calibration and characterization of surveillance and seeker systems, as well as some mission simulation. The 10V chamber is being upgraded to provide real-time target simulation during the detection, acquisition, discrimination, and terminal phases of a seeker mission. The objective of the Satellite Emulation project is to upgrade this existing capability to support the ability to discern and track other satellites and orbital debris in a HWIL capability. It would provide a baseline for realistic testing of satellite surveillance sensors, which would be operated in a controlled environment. Many sensor functions could be tested, including scene recognition and maneuvering control software, using real interceptor hardware and software. Statistically significant and repeatable datasets produced by the satellite emulation system can be acquired during such test and saved for further analysis. In addition, the robustness of the discrimination and tracking algorithms can be investigated by a parametric analysis using slightly different scenarios; this will be used to determine critical points where a sensor system might fail. The radiometric characteristics of satellites are expected to be similar to the targets and decoys that make up a typical interceptor mission scenario, since they are near ambient temperature. Their spectral reflectivity, emissivity, and shape must also be considered, but the projection systems employed in the 7V and 10V chambers should be

Comparison of neotropical migrant landbird populations wintering in tropical forest, isolated forest fragments, and agricultural habitats

USGS Publications Warehouse

Robbins, C.S.; Dowell, B.A.; Dawson, D.K.; Colon, J.A.; Estrada, R.; Sutton, A.; Sutton, R.; Weyer, D.; Hagan, John M.; Johnston, David W.

1992-01-01

Neotropical migrant bird populations were sampled at 76 sites in seven countries by using mist nets and point counts during a six-winter study. Populations in major agricultural habitats were compared with those in extensive forest and isolated forest fragments. Certain Neotropical migrants, such as the Northern Parula, American Redstart, and the Black-throated Blue, Magnolia, Black-and-white, and Hooded warblers, were present in arboreal agricultural habitats such as pine, cacao, citrus, and shade coffee plantations in relatively large numbers. Many north temperate zone shrub-nesting species, such as the Gray Catbird, White-eyed Vireo, Tennessee Warbler, Common Yellowthroat, and Indigo Bunting, also used agricultural habitats in winter, as did resident hummingbirds and migrant orioles. Ground-foraging migrants, such as thrushes and Kentucky Warblers, were rarely found in the agricultural habitats sampled. Although many Neotropical migrants use some croplands, this use might be severely limited by overgrazing by cattle, by intensive management (such as removal of ground cover in an orchard), or by heavy use of insecticides, herbicides, or fungicides.

Nesting ecology of boreal forest birds following a massive outbreak of spruce beetles

USGS Publications Warehouse

Matsuoka, S.M.; Handel, C.M.

2007-01-01

We studied breeding dark-eyed juncos (Junco hyemalis), yellow-rumped warblers (Dendroica coronata), and spruce-nesting birds from 1997 to 1998 among forests with different levels of spruce (Picea spp.) mortality following an outbreak of spruce beetles (Dendroctonus rufipennis) in Alaska, USA. We identified species using live and beetle-killed spruce for nest sites and monitored nests to determine how the outbreak influenced avian habitat selection and reproduction. We tested predictions that 1) nesting success of ground-nesting juncos would increase with spruce mortality due to proliferation of understory vegetation available to conceal nests from predators, 2) nesting success of canopy-nesting warblers would decrease with spruce mortality due to fewer live spruce in which to conceal nests, and 3) both species would alter nest-site selection in response to disturbance. Juncos did not benefit from changes in understory vegetation; nesting success in highly disturbed stands (46%) was comparable to that in undisturbed habitats throughout their range. In stands with low spruce mortality, nesting success of juncos was low (5%) and corresponded with high densities of red squirrels (Tamiasciurus hudsonicus). Yellow-rumped warblers nested exclusively in spruce, but success did not vary with spruce mortality. As disturbance increased, nesting warblers switched from selecting forest patches with high densities of live white spruce (Picea glauca) to patches with beetle-killed spruce. Warblers also placed nests in large-diameter live or beetle-killed spruce, depending on which was more abundant in the stand, with no differences in nesting success. Five of the 12 other species of spruce-nesting birds also used beetle-killed spruce as nest sites. Because beetle-killed spruce can remain standing for >50 years, even highly disturbed stands provide an important breeding resource for boreal forest birds. We recommend that boreal forest managers preserve uncut blocks of infested

Trophic cascades: linking ungulates to shrub-dependent birds and butterflies.

PubMed

J Teichman, Kristine; Nielsen, Scott E; Roland, Jens

2013-11-01

1. Studies demonstrating trophic cascades through the loss of top-down regulatory processes in productive and biologically diverse terrestrial ecosystems are limited. 2. Elk Island National Park, Alberta and surrounding protected areas have a wide range of ungulate density due to the functional loss of top predators, management for high ungulate numbers and variable hunting pressure. This provides an ideal setting for studying the effects of hyper-abundant ungulates on vegetation and shrub-dependent bird and butterfly species. 3. To examine the cascading effects of high ungulate density, we quantified vegetation characteristics and abundances of yellow warbler Dendroica petechia and Canadian tiger swallowtail Papilio canadensis under different ungulate density in and around Elk Island National Park. 4. Using Structural Equation Models we found that ungulate density was inversely related to shrub cover, whereas shrub cover was positively related to yellow warbler abundance. In addition, chokecherry Prunus virginiana abundance was inversely related to browse impact but positively related to P. canadensis abundance. 5. These results demonstrate a cascade resulting from hyper-abundant ungulates on yellow warblers and Canadian tiger swallowtails through reductions in shrub cover and larval host plant density. The combined effect of the functional loss of top predators and management strategies that maintain high ungulate numbers can decouple top-down regulation of productive temperate ecosystems. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Hardware-in-the-Loop emulator for a hydrokinetic turbine

NASA Astrophysics Data System (ADS)

Rat, C. L.; Prostean, O.; Filip, I.

2018-01-01

Hydroelectric power has proven to be an efficient and reliable form of renewable energy, but its impact on the environment has long been a source of concern. Hydrokinetic turbines are an emerging class of renewable energy technology designed for deployment in small rivers and streams with minimal environmental impact on the local ecosystem. Hydrokinetic technology represents a truly clean source of energy, having the potential to become a highly efficient method of harvesting renewable energy. However, in order to achieve this goal, extensive research is necessary. This paper presents a Hardware-in-the-Loop emulator for a run-of-the-river type hydrokinetic turbine. The HIL system uses an ABB ACS800 drive to control an induction machine as a significant means of replicating the behavior of the real turbine. The induction machine is coupled to a permanent magnet synchronous generator and the corresponding load. The ACS800 drive is controlled through the software system, which comprises of the hydrokinetic turbine real-time simulation through mathematical modeling in the LabVIEW programming environment running on a NI CompactRIO (cRIO) platform. The advantages of this method are that it can provide a means for testing many control configurations without requiring the presence of the real turbine. This paper contains the basic principles of a hydrokinetic turbine, particularly the run-of-the-river configurations along with the experimental results obtained from the HIL system.

Towards an acoustical platform for many-body spin emulation: Transmon qubits patterned on a piezoelectric material

NASA Astrophysics Data System (ADS)

Moores, Brad A.; Sletten, Lucas R.; Viennot, Jeremie; Lehnert, K. W.

Man-made systems of interacting qubits are a promising and powerful way of exploring many-body spin physics beyond classical computation. Although transmon qubits are perhaps the most advanced quantum computing technology, building a system of such qubits designed to emulate a system of many interacting spins is hindered by the mismatch of scales between the transmons and the electromagnetic modes that couple them. We propose a strategy to overcome this mismatch by using surface acoustic waves, which couple to qubits piezoelectrically and have micron wavelengths at GHz frequencies. In this talk, we will present characterizations of transmon qubits fabricated on a piezoelectric material, and show that their coherence properties are sufficient to explore acoustically mediated qubit interactions.

Emulating JWST Exoplanet Transit Observations in a Testbed laboratory experiment

NASA Astrophysics Data System (ADS)

Touli, D.; Beichman, C. A.; Vasisht, G.; Smith, R.; Krist, J. E.

2014-12-01

The transit technique is used for the detection and characterization of exoplanets. The combination of transit and radial velocity (RV) measurements gives information about a planet's radius and mass, respectively, leading to an estimate of the planet's density (Borucki et al. 2011) and therefore to its composition and evolutionary history. Transit spectroscopy can provide information on atmospheric composition and structure (Fortney et al. 2013). Spectroscopic observations of individual planets have revealed atomic and molecular species such as H2O, CO2 and CH4 in atmospheres of planets orbiting bright stars, e.g. Deming et al. (2013). The transit observations require extremely precise photometry. For instance, Jupiter transit results to a 1% brightness decrease of a solar type star while the Earth causes only a 0.0084% decrease (84 ppm). Spectroscopic measurements require still greater precision <30ppm. The Precision Projector Laboratory (PPL) is a collaboration between the Jet Propulsion Laboratory (JPL) and California Institute of Technology (Caltech) to characterize and validate detectors through emulation of science images. At PPL we have developed a testbed to project simulated spectra and other images onto a HgCdTe array in order to assess precision photometry for transits, weak lensing etc. for Explorer concepts like JWST, WFIRST, EUCLID. In our controlled laboratory experiment, the goal is to demonstrate ability to extract weak transit spectra as expected for NIRCam, NIRIS and NIRSpec. Two lamps of variable intensity, along with spectral line and photometric simulation masks emulate the signals from a star-only, from a planet-only and finally, from a combination of a planet + star. Three masks have been used to simulate spectra in monochromatic light. These masks, which are fabricated at JPL, have a length of 1000 pixels and widths of 2 pixels, 10 pixels and 1 pixel to correspond respectively to the noted above JWST instruments. From many-hour long

Combined aerodynamic and structural dynamic problem emulating routines (CASPER): Theory and implementation

NASA Technical Reports Server (NTRS)

Jones, William H.

1985-01-01

The Combined Aerodynamic and Structural Dynamic Problem Emulating Routines (CASPER) is a collection of data-base modification computer routines that can be used to simulate Navier-Stokes flow through realistic, time-varying internal flow fields. The Navier-Stokes equation used involves calculations in all three dimensions and retains all viscous terms. The only term neglected in the current implementation is gravitation. The solution approach is of an interative, time-marching nature. Calculations are based on Lagrangian aerodynamic elements (aeroelements). It is assumed that the relationships between a particular aeroelement and its five nearest neighbor aeroelements are sufficient to make a valid simulation of Navier-Stokes flow on a small scale and that the collection of all small-scale simulations makes a valid simulation of a large-scale flow. In keeping with these assumptions, it must be noted that CASPER produces an imitation or simulation of Navier-Stokes flow rather than a strict numerical solution of the Navier-Stokes equation. CASPER is written to operate under the Parallel, Asynchronous Executive (PAX), which is described in a separate report.

Large-displacement structural durability analyses of simple bend specimen emulating rocket nozzle liners

NASA Technical Reports Server (NTRS)

Arya, Vinod K.; Halford, Gary R.

1994-01-01

Large-displacement elastic and elastic-plastic, finite-element stress-strain analyses of an oxygen-tree high-conductivity (OFHC) copper plate specimen were performed using an updated Lagrangian formulation. The plate specimen is intended for low-cost experiments that emulate the most important thermomechanical loading and failure modes of a more complex rocket nozzle. The plate, which is loaded in bending at 593 C, contains a centrally located and internally pressurized channel. The cyclic crack initiation lives were estimated using the results from the analyses and isothermal strain-controlled low-cycle fatigue data for OFHC copper. A comparison of the predicted and experimental cyclic lives showed that an elastic analysis predicts a longer cyclic life than that observed in experiments by a factor greater than 4. The results from elastic-plastic analysis for the plate bend specimen, however, predicted a cyclic life in close agreement with experiment, thus justifying the need for the more rigorous stress-strain analysis.

Subspace projection method for unstructured searches with noisy quantum oracles using a signal-based quantum emulation device

NASA Astrophysics Data System (ADS)

La Cour, Brian R.; Ostrove, Corey I.

2017-01-01

This paper describes a novel approach to solving unstructured search problems using a classical, signal-based emulation of a quantum computer. The classical nature of the representation allows one to perform subspace projections in addition to the usual unitary gate operations. Although bandwidth requirements will limit the scale of problems that can be solved by this method, it can nevertheless provide a significant computational advantage for problems of limited size. In particular, we find that, for the same number of noisy oracle calls, the proposed subspace projection method provides a higher probability of success for finding a solution than does an single application of Grover's algorithm on the same device.

Signal pulse emulation for scintillation detectors using Geant4 Monte Carlo with light tracking simulation.

PubMed

Ogawara, R; Ishikawa, M

2016-07-01

The anode pulse of a photomultiplier tube (PMT) coupled with a scintillator is used for pulse shape discrimination (PSD) analysis. We have developed a novel emulation technique for the PMT anode pulse based on optical photon transport and a PMT response function. The photon transport was calculated using Geant4 Monte Carlo code and the response function with a BC408 organic scintillator. The obtained percentage RMS value of the difference between the measured and simulated pulse with suitable scintillation properties using GSO:Ce (0.4, 1.0, 1.5 mol%), LaBr3:Ce and BGO scintillators were 2.41%, 2.58%, 2.16%, 2.01%, and 3.32%, respectively. The proposed technique demonstrates high reproducibility of the measured pulse and can be applied to simulation studies of various radiation measurements.

High speed fault tolerant secure communication for muon chamber using FPGA based GBTx emulator

NASA Astrophysics Data System (ADS)

Sau, Suman; Mandal, Swagata; Saini, Jogender; Chakrabarti, Amlan; Chattopadhyay, Subhasis

2015-12-01

The Compressed Baryonic Matter (CBM) experiment is a part of the Facility for Antiproton and Ion Research (FAIR) in Darmstadt at the GSI. The CBM experiment will investigate the highly compressed nuclear matter using nucleus-nucleus collisions. This experiment will examine lieavy-ion collisions in fixed target geometry and will be able to measure hadrons, electrons and muons. CBM requires precise time synchronization, compact hardware, radiation tolerance, self-triggered front-end electronics, efficient data aggregation schemes and capability to handle high data rate (up to several TB/s). As a part of the implementation of read out chain of Muon Cliamber(MUCH) [1] in India, we have tried to implement FPGA based emulator of GBTx in India. GBTx is a radiation tolerant ASIC that can be used to implement multipurpose high speed bidirectional optical links for high-energy physics (HEP) experiments and is developed by CERN. GBTx will be used in highly irradiated area and more prone to be affected by multi bit error. To mitigate this effect instead of single bit error correcting RS code we have used two bit error correcting (15, 7) BCH code. It will increase the redundancy which in turn increases the reliability of the coded data. So the coded data will be less prone to be affected by noise due to radiation. The data will go from detector to PC through multiple nodes through the communication channel. The computing resources are connected to a network which can be accessed by authorized person to prevent unauthorized data access which might happen by compromising the network security. Thus data encryption is essential. In order to make the data communication secure, advanced encryption standard [2] (AES - a symmetric key cryptography) and RSA [3], [4] (asymmetric key cryptography) are used after the channel coding. We have implemented GBTx emulator on two Xilinx Kintex-7 boards (KC705). One will act as transmitter and other will act as receiver and they are connected

Hospital management principles applicable to the veterinary teaching hospital.

PubMed

Harris, Donna L; Lloyd, James W; Marrinan, Mike

2004-01-01

The Skills, Knowledge, Aptitude, and Attitude (SKA) Subcommittee of the National Commission on Veterinary Economic Issues (NCVEI) has identified the need for veterinary teaching hospitals (VTH) to be at the forefront of progressive business management to serve as a model for both students and practitioners to emulate. To provide a foundation for developing a model, this study reviewed pertinent literature applicable to the management of a VTH. Much of the literature relevant to VTH management relates to work completed for the human side of medicine (academic health centers, or AHCs) or to the private sector. This review explores management practices in strategic planning, financial management, human resource management, marketing, pricing, operations, and legal issues. It is concluded that strategic management is important to provide the foundation for success in the VTH. In addition, periodic financial reports are recommended, as are the development and use of benchmarks for financial management. Establishing positive, motivating human resource practices is also suggested, along with development of a marketing plan based on a clear understanding of VTH core competencies and the market's specific needs.

50 CFR 32.41 - Michigan.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... Migratory Game Bird Hunting. [Reserved] B. Upland Game Hunting. [Reserved] C. Big Game Hunting. Hunting of.... [Reserved] Kirtland's Warbler Wildlife Management Area A. Migratory Game Bird Hunting. Hunting is pursuant to State regulation. B. Upland Game Hunting. Hunting is pursuant to State regulation. C. Big Game...

50 CFR 32.41 - Michigan.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... Migratory Game Bird Hunting. [Reserved] B. Upland Game Hunting. [Reserved] C. Big Game Hunting. We allow.... [Reserved] Kirtland's Warbler Wildlife Management Area A. Migratory Game Bird Hunting. Hunting is pursuant to State regulation. B. Upland Game Hunting. Hunting is pursuant to State regulation. C. Big Game...

Bayesian uncertainty analysis for complex systems biology models: emulation, global parameter searches and evaluation of gene functions.

PubMed

Vernon, Ian; Liu, Junli; Goldstein, Michael; Rowe, James; Topping, Jen; Lindsey, Keith

2018-01-02

Many mathematical models have now been employed across every area of systems biology. These models increasingly involve large numbers of unknown parameters, have complex structure which can result in substantial evaluation time relative to the needs of the analysis, and need to be compared to observed data of various forms. The correct analysis of such models usually requires a global parameter search, over a high dimensional parameter space, that incorporates and respects the most important sources of uncertainty. This can be an extremely difficult task, but it is essential for any meaningful inference or prediction to be made about any biological system. It hence represents a fundamental challenge for the whole of systems biology. Bayesian statistical methodology for the uncertainty analysis of complex models is introduced, which is designed to address the high dimensional global parameter search problem. Bayesian emulators that mimic the systems biology model but which are extremely fast to evaluate are embeded within an iterative history match: an efficient method to search high dimensional spaces within a more formal statistical setting, while incorporating major sources of uncertainty. The approach is demonstrated via application to a model of hormonal crosstalk in Arabidopsis root development, which has 32 rate parameters, for which we identify the sets of rate parameter values that lead to acceptable matches between model output and observed trend data. The multiple insights into the model's structure that this analysis provides are discussed. The methodology is applied to a second related model, and the biological consequences of the resulting comparison, including the evaluation of gene functions, are described. Bayesian uncertainty analysis for complex models using both emulators and history matching is shown to be a powerful technique that can greatly aid the study of a large class of systems biology models. It both provides insight into model behaviour

Synesthesia, sensory-motor contingency, and semantic emulation: how swimming style-color synesthesia challenges the traditional view of synesthesia.

PubMed

Mroczko-Wąsowicz, Aleksandra; Werning, Markus

2012-01-01

Synesthesia is traditionally regarded as a phenomenon in which an additional non-standard phenomenal experience occurs consistently in response to ordinary stimulation applied to the same or another modality. Recent studies suggest an important role of semantic representations in the induction of synesthesia. In the present proposal we try to link the empirically grounded theory of sensory-motor contingency and mirror system based embodied simulation/emulation to newly discovered cases of swimming style-color synesthesia. In the latter color experiences are evoked only by showing the synesthetes a picture of a swimming person or asking them to think about a given swimming style. Neural mechanisms of mirror systems seem to be involved here. It has been shown that for mirror-sensory synesthesia, such as mirror-touch or mirror-pain synesthesia (when visually presented tactile or noxious stimulation of others results in the projection of the tactile or pain experience onto oneself), concurrent experiences are caused by overactivity in the mirror neuron system responding to the specific observation. The comparison of different forms of synesthesia has the potential of challenging conventional thinking on this phenomenon and providing a more general, sensory-motor account of synesthesia encompassing cases driven by semantic or emulational rather than pure sensory or motor representations. Such an interpretation could include top-down associations, questioning the explanation in terms of hard-wired structural connectivity. In the paper the hypothesis is developed that the wide-ranging phenomenon of synesthesia might result from a process of hyperbinding between "too many" semantic attribute domains. This hypothesis is supplemented by some suggestions for an underlying neural mechanism.

Synesthesia, Sensory-Motor Contingency, and Semantic Emulation: How Swimming Style-Color Synesthesia Challenges the Traditional View of Synesthesia

PubMed Central

Mroczko-Wąsowicz, Aleksandra; Werning, Markus

2012-01-01

Synesthesia is traditionally regarded as a phenomenon in which an additional non-standard phenomenal experience occurs consistently in response to ordinary stimulation applied to the same or another modality. Recent studies suggest an important role of semantic representations in the induction of synesthesia. In the present proposal we try to link the empirically grounded theory of sensory-motor contingency and mirror system based embodied simulation/emulation to newly discovered cases of swimming style-color synesthesia. In the latter color experiences are evoked only by showing the synesthetes a picture of a swimming person or asking them to think about a given swimming style. Neural mechanisms of mirror systems seem to be involved here. It has been shown that for mirror-sensory synesthesia, such as mirror-touch or mirror-pain synesthesia (when visually presented tactile or noxious stimulation of others results in the projection of the tactile or pain experience onto oneself), concurrent experiences are caused by overactivity in the mirror neuron system responding to the specific observation. The comparison of different forms of synesthesia has the potential of challenging conventional thinking on this phenomenon and providing a more general, sensory-motor account of synesthesia encompassing cases driven by semantic or emulational rather than pure sensory or motor representations. Such an interpretation could include top-down associations, questioning the explanation in terms of hard-wired structural connectivity. In the paper the hypothesis is developed that the wide-ranging phenomenon of synesthesia might result from a process of hyperbinding between “too many” semantic attribute domains. This hypothesis is supplemented by some suggestions for an underlying neural mechanism. PMID:22936919

Neurokernel: An Open Source Platform for Emulating the Fruit Fly Brain

PubMed Central

2016-01-01

We have developed an open software platform called Neurokernel for collaborative development of comprehensive models of the brain of the fruit fly Drosophila melanogaster and their execution and testing on multiple Graphics Processing Units (GPUs). Neurokernel provides a programming model that capitalizes upon the structural organization of the fly brain into a fixed number of functional modules to distinguish between these modules’ local information processing capabilities and the connectivity patterns that link them. By defining mandatory communication interfaces that specify how data is transmitted between models of each of these modules regardless of their internal design, Neurokernel explicitly enables multiple researchers to collaboratively model the fruit fly’s entire brain by integration of their independently developed models of its constituent processing units. We demonstrate the power of Neurokernel’s model integration by combining independently developed models of the retina and lamina neuropils in the fly’s visual system and by demonstrating their neuroinformation processing capability. We also illustrate Neurokernel’s ability to take advantage of direct GPU-to-GPU data transfers with benchmarks that demonstrate scaling of Neurokernel’s communication performance both over the number of interface ports exposed by an emulation’s constituent modules and the total number of modules comprised by an emulation. PMID:26751378

Signal pulse emulation for scintillation detectors using Geant4 Monte Carlo with light tracking simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ogawara, R.; Ishikawa, M., E-mail: masayori@med.hokudai.ac.jp

The anode pulse of a photomultiplier tube (PMT) coupled with a scintillator is used for pulse shape discrimination (PSD) analysis. We have developed a novel emulation technique for the PMT anode pulse based on optical photon transport and a PMT response function. The photon transport was calculated using Geant4 Monte Carlo code and the response function with a BC408 organic scintillator. The obtained percentage RMS value of the difference between the measured and simulated pulse with suitable scintillation properties using GSO:Ce (0.4, 1.0, 1.5 mol%), LaBr{sub 3}:Ce and BGO scintillators were 2.41%, 2.58%, 2.16%, 2.01%, and 3.32%, respectively. The proposedmore » technique demonstrates high reproducibility of the measured pulse and can be applied to simulation studies of various radiation measurements.« less

Preface

Treesearch

W. Mark Ford; Kevin R. Russell; Christopher E. Moorman

2002-01-01

Fire has a long history of regional use in the United States for forest, range and game management. Except for a few high-profile threatened, endangered, and sensitive species such as the pine barrens treefrog (Hyla andersonii), the red-cockaded woodpecker (Picoides borealis), and the Kirtland?s warbler (Dendroica...

Model description document for a computer program for the emulation/simulation of a space station environmental control and life support system (ESCM)

NASA Technical Reports Server (NTRS)

Yanosy, James L.

1988-01-01

Emulation/Simulation Computer Model (ESCM) computes the transient performance of a Space Station air revitalization subsystem with carbon dioxide removal provided by a solid amine water desorbed subsystem called SAWD. This manual describes the mathematical modeling and equations used in the ESCM. For the system as a whole and for each individual component, the fundamental physical and chemical laws which govern their operations are presented. Assumptions are stated, and when necessary, data is presented to support empirically developed relationships.

History matching of a complex epidemiological model of human immunodeficiency virus transmission by using variance emulation.

PubMed

Andrianakis, I; Vernon, I; McCreesh, N; McKinley, T J; Oakley, J E; Nsubuga, R N; Goldstein, M; White, R G

2017-08-01

Complex stochastic models are commonplace in epidemiology, but their utility depends on their calibration to empirical data. History matching is a (pre)calibration method that has been applied successfully to complex deterministic models. In this work, we adapt history matching to stochastic models, by emulating the variance in the model outputs, and therefore accounting for its dependence on the model's input values. The method proposed is applied to a real complex epidemiological model of human immunodeficiency virus in Uganda with 22 inputs and 18 outputs, and is found to increase the efficiency of history matching, requiring 70% of the time and 43% fewer simulator evaluations compared with a previous variant of the method. The insight gained into the structure of the human immunodeficiency virus model, and the constraints placed on it, are then discussed.

Space Link Extension (SLE) Emulation for High-Throughput Network Communication

NASA Technical Reports Server (NTRS)

Murawski, Robert; Tchorowski, Nicole; Golden, Bert

2014-01-01

As the data rate requirements for space communications increases, signicant stressis placed not only on the wireless satellite communication links, but also on the groundnetworks which forward data from end-users to remote ground stations. These wide areanetwork (WAN) connections add delay and jitter to the end-to-end satellite communicationlink, eects which can have signicant impacts on the wireless communication link. It isimperative that any ground communication protocol can react to these eects such that theground network does not become a bottleneck in the communication path to the satellite.In this paper, we present our SCENIC Emulation Lab testbed which was developed to testthe CCSDS SLE protocol implementations proposed for use on future NASA communica-tion networks. Our results show that in the presence of realistic levels of network delay,high-throughput SLE communication links can experience signicant data rate throttling.Based on our observations, we present some insight into why this data throttling happens,and trace the probable issue back to non-optimal blocking communication which is sup-ported by the CCSDS SLE API recommended practices. These issues were presented aswell to the SLE implementation developers which, based on our reports, developed a newrelease for SLE which we show xes the SLE blocking issue and greatly improves the pro-tocol throughput. In this paper, we also discuss future developments for our end-to-endemulation lab and how these improvements can be used to develop and test future spacecommunication technologies.

User's manual for a computer program for the emulation/simulation of a space station Environmental Control and Life Support System (ESCM)

NASA Technical Reports Server (NTRS)

Yanosy, James L.

1988-01-01

This manual describes how to use the Emulation Simulation Computer Model (ESCM). Based on G189A, ESCM computes the transient performance of a Space Station atmospheric revitalization subsystem (ARS) with CO2 removal provided by a solid amine water desorbed subsystem called SAWD. Many performance parameters are computed some of which are cabin CO2 partial pressure, relative humidity, temperature, O2 partial pressure, and dew point. The program allows the user to simulate various possible combinations of man loading, metabolic profiles, cabin volumes and certain hypothesized failures that could occur.

Primer reporte del híbrido intergenérico Vermivora chrysoptera x Vermivora pinus (“Brewsters Warbler”) en Nicaragua

Treesearch

W.J. Arendt; M.A. Tórrez

2008-01-01

This article is in Spanish. During an inventory to assess avian biodiversity among the critical watersheds that flow into the Pacific from Nicaragua, we captured a hybrid Vermivora chrysoptera (“Golden-winged Warbler”) with V. pinus (“Blue-winged Warbler”) known as Brewster’s Warbler (V. leucobronchialis). The capture ocurred on November 30, 2007 in dry forest (...

UPEML Version 3.0: A machine-portable CDC update emulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehlhorn, T.A.; Haill, T.A.

1992-04-01

UPEML is a machine-portable program that emulates a subset of the functions of the standard CDC Update. Machine-portability has been achieved by conforming to ANSI standards for Fortran-77. UPEML is compact and fairly efficient; however, it only allows a restricted syntax as compared with the CDC Update. This program was written primarily to facilitate the use of CDC-based scientific packages on alternate computer systems such as the VAX/VMS mainframes and UNIX workstations. UPEML has also been successfully used on the multiprocessor ELXSI, on CRAYs under both UNICOS and CTSS operating systems, and on Sun, HP, Stardent and IBM workstations. UPEMLmore » was originally released with the ITS electron/photon Monte Carlo transport package, which was developed on a CDC-7600 and makes extensive use of conditional file structure to combine several problem geometry and machine options into a single program file. UPEML 3.0 is an enhanced version of the original code and is being independently released for use at any installation or with any code package. Version 3.0 includes enhanced error checking, full ASCII character support, a program library audit capability, and a partial update option in which only selected or modified decks are written to the complete file. Version 3.0 also checks for overlapping corrections, allows processing of pested calls to common decks, and allows the use of alternate files in READ and ADDFILE commands. Finally, UPEML Version 3.0 allows the assignment of input and output files at runtime on the control line.« less

UPEML Version 3. 0: A machine-portable CDC update emulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehlhorn, T.A.; Haill, T.A.

1992-04-01

UPEML is a machine-portable program that emulates a subset of the functions of the standard CDC Update. Machine-portability has been achieved by conforming to ANSI standards for Fortran-77. UPEML is compact and fairly efficient; however, it only allows a restricted syntax as compared with the CDC Update. This program was written primarily to facilitate the use of CDC-based scientific packages on alternate computer systems such as the VAX/VMS mainframes and UNIX workstations. UPEML has also been successfully used on the multiprocessor ELXSI, on CRAYs under both UNICOS and CTSS operating systems, and on Sun, HP, Stardent and IBM workstations. UPEMLmore » was originally released with the ITS electron/photon Monte Carlo transport package, which was developed on a CDC-7600 and makes extensive use of conditional file structure to combine several problem geometry and machine options into a single program file. UPEML 3.0 is an enhanced version of the original code and is being independently released for use at any installation or with any code package. Version 3.0 includes enhanced error checking, full ASCII character support, a program library audit capability, and a partial update option in which only selected or modified decks are written to the complete file. Version 3.0 also checks for overlapping corrections, allows processing of pested calls to common decks, and allows the use of alternate files in READ and ADDFILE commands. Finally, UPEML Version 3.0 allows the assignment of input and output files at runtime on the control line.« less

A Novel Resource Management Method of Providing Operating System as a Service for Mobile Transparent Computing

PubMed Central

Huang, Suzhen; Wu, Min; Zhang, Yaoxue; She, Jinhua

2014-01-01

This paper presents a framework for mobile transparent computing. It extends the PC transparent computing to mobile terminals. Since resources contain different kinds of operating systems and user data that are stored in a remote server, how to manage the network resources is essential. In this paper, we apply the technologies of quick emulator (QEMU) virtualization and mobile agent for mobile transparent computing (MTC) to devise a method of managing shared resources and services management (SRSM). It has three layers: a user layer, a manage layer, and a resource layer. A mobile virtual terminal in the user layer and virtual resource management in the manage layer cooperate to maintain the SRSM function accurately according to the user's requirements. An example of SRSM is used to validate this method. Experiment results show that the strategy is effective and stable. PMID:24883353

A novel resource management method of providing operating system as a service for mobile transparent computing.

PubMed

Xiong, Yonghua; Huang, Suzhen; Wu, Min; Zhang, Yaoxue; She, Jinhua

2014-01-01

This paper presents a framework for mobile transparent computing. It extends the PC transparent computing to mobile terminals. Since resources contain different kinds of operating systems and user data that are stored in a remote server, how to manage the network resources is essential. In this paper, we apply the technologies of quick emulator (QEMU) virtualization and mobile agent for mobile transparent computing (MTC) to devise a method of managing shared resources and services management (SRSM). It has three layers: a user layer, a manage layer, and a resource layer. A mobile virtual terminal in the user layer and virtual resource management in the manage layer cooperate to maintain the SRSM function accurately according to the user's requirements. An example of SRSM is used to validate this method. Experiment results show that the strategy is effective and stable.

Concentrating anthropogenic disturbance to balance ecological and economic values: applications to forest management.

PubMed

Tittler, Rebecca; Messier, Christian; Fall, Andrew

2012-06-01

To maintain healthy ecosystems, natural-disturbance-based management aims to minimize differences between unmanaged and managed landscapes. Two related approaches may help accomplish this goal, either applied together or in isolation: (1) concentrating anthropogenic disturbance through zoning (with protected areas and intensive management); and (2) emulating natural disturbances. The purpose of this paper is to examine the effects of these two approaches, applied both in isolation and in combination, on the structure of the forest landscape. To do so, we use a spatially explicit landscape simulation model on a large fire-dominated landscape in eastern Canada. Specifically, we examine the effects of (1) increasing the maximum size of logged stands (cutblocks) to better emulate the full range of fire sizes in a fire-dominated landscape, (2) increasing protected areas, and (3) adding aggregated or dispersed intensive wood production areas to the landscape in addition to protected areas (triad management). We focus on maximizing the amount and minimizing the fragmentation of old-growth forest and on reducing road construction. Increasing maximum cutblock size and adding protected areas led to reduced road construction, while the latter also resulted in less fragmentation and more old growth. Although protected areas led to reduced harvest volume, the addition of an intensive production zone (triad management) counterbalanced this loss and resulted in more old growth than equivalent scenarios with protected areas but no intensive production zone. However, we found no differences between aggregated and dispersed intensive wood production. Our results imply that differences between unmanaged and managed landscapes can be reduced by concentrating logging efforts through a combination of protected areas and intensive wood production, and by creating some larger cutblocks. We conclude that the forest industry and regulators should therefore seek to increase protected areas

Adapting to the 30-degree visual perspective by emulating the angled laparoscope: a simple and low-cost solution for basic surgical training.

PubMed

Daniel, Lorias Espinoza; Tapia, Fernando Montes; Arturo, Minor Martínez; Ricardo, Ordorica Flores

2014-12-01

The ability to handle and adapt to the visual perspectives generated by angled laparoscopes is crucial for skilled laparoscopic surgery. However, the control of the visual work space depends on the ability of the operator of the camera, who is often not the most experienced member of the surgical team. Here, we present a simple, low-cost option for surgical training that challenges the learner with static and dynamic visual perspectives at 30 degrees using a system that emulates the angled laparoscope. A system was developed using a low-cost camera and readily available materials to emulate the angled laparoscope. Nine participants undertook 3 tasks to test spatial adaptation to the static and dynamic visual perspectives at 30 degrees. Completing each task to a predefined satisfactory level ensured precision of execution of the tasks. Associated metrics (time and error rate) were recorded, and the performance of participants were determined. A total of 450 repetitions were performed by 9 residents at various stages of training. All the tasks were performed with a visual perspective of 30 degrees using the system. Junior residents were more proficient than senior residents. This system is a viable and low-cost alternative for developing the basic psychomotor skills necessary for the handling and adaptation to visual perspectives of 30 degrees, without depending on a laparoscopic tower, in junior residents. More advanced skills may then be acquired by other means, such as in the operating theater or through clinical experience.

An advanced real-time digital signal processing system for linear systems emulation, with special emphasis on network and acoustic response characterization

NASA Astrophysics Data System (ADS)

Gaydecki, Patrick; Fernandes, Bosco

2003-11-01

A fast digital signal processing (DSP) system is described that can perform real-time emulation of a wide variety of linear audio-bandwidth systems and networks, such as reverberant spaces, musical instrument bodies and very high order filter networks. The hardware design is based upon a Motorola DSP56309 operating at 110 million multiplication-accumulations per second and a dual-channel 24 bit codec with a maximum sampling frequency of 192 kHz. High level software has been developed to express complex vector frequency responses as both infinite impulse response (IIR) and finite impulse response (FIR) coefficients, in a form suitable for real-time convolution by the firmware installed in the DSP system memory. An algorithm has also been devised to express IIR filters as equivalent FIR structures, thereby obviating the potential instabilities associated with recursive equations and negating the traditional deficiencies of FIR filters respecting equivalent analogue designs. The speed and dynamic range of the system is such that, when sampling at 48 kHz, the frequency response can be specified to a spectral precision of 22 Hz when sampling at 10 kHz, this resolution increases to 0.9 Hz. Moreover, it is also possible to control the phase of any frequency band with a theoretical precision of 10-5 degrees in all cases. The system has been applied in the study of analogue filter networks, real-time Hilbert transformation, phase-shift systems and musical instrument body emulation, where it is providing valuable new insights into the understanding of psychoacoustic mechanisms.

Research on an expert system for database operation of simulation-emulation math models. Volume 1, Phase 1: Results

NASA Technical Reports Server (NTRS)

Kawamura, K.; Beale, G. O.; Schaffer, J. D.; Hsieh, B. J.; Padalkar, S.; Rodriguez-Moscoso, J. J.

1985-01-01

The results of the first phase of Research on an Expert System for Database Operation of Simulation/Emulation Math Models, is described. Techniques from artificial intelligence (AI) were to bear on task domains of interest to NASA Marshall Space Flight Center. One such domain is simulation of spacecraft attitude control systems. Two related software systems were developed to and delivered to NASA. One was a generic simulation model for spacecraft attitude control, written in FORTRAN. The second was an expert system which understands the usage of a class of spacecraft attitude control simulation software and can assist the user in running the software. This NASA Expert Simulation System (NESS), written in LISP, contains general knowledge about digital simulation, specific knowledge about the simulation software, and self knowledge.

Palaeoclimatic events, dispersal and migratory losses along the Afro-European axis as drivers of biogeographic distribution in Sylvia warblers.

PubMed

Voelker, Gary; Light, Jessica E

2011-06-14

The Old World warbler genus Sylvia has been used extensively as a model system in a variety of ecological, genetic, and morphological studies. The genus is comprised of about 25 species, and 70% of these species have distributions at or near the Mediterranean Sea. This distribution pattern suggests a possible role for the Messinian Salinity Crisis (from 5.96-5.33 Ma) as a driving force in lineage diversification. Other species distributions suggest that Late Miocene to Pliocene Afro-tropical forest dynamics have also been important in the evolution of Sylvia lineages. Using a molecular phylogenetic hypothesis and other methods, we seek to develop a biogeographic hypothesis for Sylvia and to explicitly assess the roles of these climate-driven events. We present the first strongly supported molecular phylogeny for Sylvia. With one exception, species fall into one of three strongly supported clades: one small clade of species distributed mainly in Africa and Europe, one large clade of species distributed mainly in Africa and Asia, and another large clade with primarily a circum-Mediterranean distribution. Asia is reconstructed as the ancestral area for Sylvia. Long-distance migration is reconstructed as the ancestral character state for the genus, and sedentary behavior subsequently evolved seven times. Molecular clock calibration suggests that Sylvia arose in the early Miocene and diverged into three main clades by 12.6 Ma. Divergence estimates indicate that the Messinian Salinity Crisis had a minor impact on Sylvia. Instead, over-water dispersals, repeated loss of long-distance migration, and palaeo-climatic events in Africa played primary roles in Sylvia divergence and distribution.

Advanced data management system architectures testbed

NASA Technical Reports Server (NTRS)

Grant, Terry

1990-01-01

The objective of the Architecture and Tools Testbed is to provide a working, experimental focus to the evolving automation applications for the Space Station Freedom data management system. Emphasis is on defining and refining real-world applications including the following: the validation of user needs; understanding system requirements and capabilities; and extending capabilities. The approach is to provide an open, distributed system of high performance workstations representing both the standard data processors and networks and advanced RISC-based processors and multiprocessor systems. The system provides a base from which to develop and evaluate new performance and risk management concepts and for sharing the results. Participants are given a common view of requirements and capability via: remote login to the testbed; standard, natural user interfaces to simulations and emulations; special attention to user manuals for all software tools; and E-mail communication. The testbed elements which instantiate the approach are briefly described including the workstations, the software simulation and monitoring tools, and performance and fault tolerance experiments.

Pinatubo Emulation in Multiple Models (POEMs): co-ordinated experiments in the ISA-MIP model intercomparison activity component of the SPARC Stratospheric Sulphur and it's Role in Climate initiative (SSiRC)

NASA Astrophysics Data System (ADS)

Lee, Lindsay; Mann, Graham; Carslaw, Ken; Toohey, Matthew; Aquila, Valentina

2016-04-01

The World Climate Research Program's SPARC initiative has a new international activity "Stratospheric Sulphur and its Role in Climate" (SSiRC) to better understand changes in stratospheric aerosol and precursor gaseous sulphur species. One component of SSiRC involves an intercomparison "ISA-MIP" of composition-climate models that simulate the stratospheric aerosol layer interactively. Within PoEMS each modelling group will run a "perturbed physics ensemble" (PPE) of interactive stratospheric aerosol (ISA) simulations of the Pinatubo eruption, varying several uncertain parameters associated with the eruption's SO2 emissions and model processes. A powerful new technique to quantify and attribute sources of uncertainty in complex global models is described by Lee et al. (2011, ACP). The analysis uses Gaussian emulation to derive a probability density function (pdf) of predicted quantities, essentially interpolating the PPE results in multi-dimensional parameter space. Once trained on the ensemble, a Monte Carlo simulation with the fast Gaussian emulator enabling a full variance-based sensitivity analysis. The approach has already been used effectively by Carslaw et al., (2013, Nature) to quantify the uncertainty in the cloud albedo effect forcing from a 3D global aerosol-microphysics model allowing to compare the sensitivy of different predicted quantities to uncertainties in natural and anthropogenic emissions types, and structural parameters in the models. Within ISA-MIP, each group will carry out a PPE of runs, with the subsequent analysis with the emulator assessing the uncertainty in the volcanic forcings predicted by each model. In this poster presentation we will give an outline of the "PoEMS" analysis, describing the uncertain parameters to be varied and the relevance to further understanding differences identified in previous international stratospheric aerosol assessments.

Functional attributes of two subtropical shrubs and implications for the distribution and management of endangered bird habitat

Treesearch

G. M. Fleming; J. M. Wunderle; D. N. Ewert; J. J. O' Brien; E. H. Helmer

2015-01-01

Aims The fruits of Erithalis fruticosa L. and Lantana involucrata L. are important in the diet of US federally endangered Kirtland’s Warblers (Setophaga kirtlandii) wintering in the Bahamas archipelago. These two shrubs occur in tropical and subtropical dry forests, including forests that have been subjected to recent disturbance. Despite their importance to the...

Mississippi River Headwaters Reservoirs. Minnesota Master Plan for Public Use Development and Resource Management.

DTIC Science & Technology

1977-12-06

Red Oak Woodchuck• ~~Paper BirchWodhc White Tailed Deer SHRUBS BIRDS Chokecherry Great Blue HeronAlwde Common Egret Dogwood Woodduck HERBS...SHRUBS BIRDS Hazelnut Eagle Chokecherry Hawks Juneberry Great Horned Owl Woodpeckers HERBS Chickadee Hepatica Wren Violet Warblers Solomons Seal Sparrows...Snowshoe Hare N. Red Oak Woodchuck Paper Birch White Tailed Deer SHRUBS BIRDS Chokecherry Great Blue Heron Alder Common Egret Dogwood Woodduck HERBS

A multichip aVLSI system emulating orientation selectivity of primary visual cortical cells.

PubMed

Shimonomura, Kazuhiro; Yagi, Tetsuya

2005-07-01

In this paper, we designed and fabricated a multichip neuromorphic analog very large scale integrated (aVLSI) system, which emulates the orientation selective response of the simple cell in the primary visual cortex. The system consists of a silicon retina and an orientation chip. An image, which is filtered by a concentric center-surround (CS) antagonistic receptive field of the silicon retina, is transferred to the orientation chip. The image transfer from the silicon retina to the orientation chip is carried out with analog signals. The orientation chip selectively aggregates multiple pixels of the silicon retina, mimicking the feedforward model proposed by Hubel and Wiesel. The chip provides the orientation-selective (OS) outputs which are tuned to 0 degrees, 60 degrees, and 120 degrees. The feed-forward aggregation reduces the fixed pattern noise that is due to the mismatch of the transistors in the orientation chip. The spatial properties of the orientation selective response were examined in terms of the adjustable parameters of the chip, i.e., the number of aggregated pixels and size of the receptive field of the silicon retina. The multichip aVLSI architecture used in the present study can be applied to implement higher order cells such as the complex cell of the primary visual cortex.

Habitat Evaluation Procedures (HEP) Report; Precious Lands Wildlife Management Area, Technical Report 2000-2003.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozusko, Shana

The Nez Perce Tribe (NPT) currently manages a 15,325 acre parcel of land known as the Precious Lands Wildlife Management Area that was purchased as mitigation for losses incurred by construction of the four lower Snake River dams. The Management Area is located in northern Wallowa County, Oregon and southern Asotin County, Washington (Figure 1). It is divided into three management parcels--the Buford parcel is located on Buford Creek and straddles the WA-OR state line, and the Tamarack and Basin parcels are contiguous to each other and located between the Joseph Creek and Cottonwood Creek drainages in Wallowa County, OR.more » The project was developed under the Pacific Northwest Electric Power Planning and Conservation Act of 1980 (P.L. 96-501), with funding from the Bonneville Power Administration (BPA). The acreage protected under this contract will be credited to BPA as habitat permanently dedicated to wildlife and wildlife mitigation. A modeling strategy known as Habitat Evaluation Procedure (HEP) was developed by the U.S. Fish and Wildlife Service and adopted by BPA as a habitat equivalency accounting system. Nine wildlife species models were used to evaluate distinct cover type features and provide a measure of habitat quality. Models measure a wide range of life requisite variables for each species and monitor overall trends in vegetation community health and diversity. One product of HEP is an evaluation of habitat quality expressed in Habitat Units (HUs). This HU accounting system is used to determine the amount of credit BPA receives for mitigation lands. After construction of the four lower Snake River dams, a HEP loss assessment was conducted to determine how many Habitat Units were inundated behind the dams. Twelve target species were used in that evaluation: Canada goose, mallard, river otter, downy woodpecker, song sparrow, yellow warbler, marsh wren, western meadowlark, chukar, ring-necked pheasant, California quail, and mule deer. The U.S. Army

Palaeoclimatic events, dispersal and migratory losses along the Afro-European axis as drivers of biogeographic distribution in Sylvia warblers

PubMed Central

2011-01-01

Background The Old World warbler genus Sylvia has been used extensively as a model system in a variety of ecological, genetic, and morphological studies. The genus is comprised of about 25 species, and 70% of these species have distributions at or near the Mediterranean Sea. This distribution pattern suggests a possible role for the Messinian Salinity Crisis (from 5.96-5.33 Ma) as a driving force in lineage diversification. Other species distributions suggest that Late Miocene to Pliocene Afro-tropical forest dynamics have also been important in the evolution of Sylvia lineages. Using a molecular phylogenetic hypothesis and other methods, we seek to develop a biogeographic hypothesis for Sylvia and to explicitly assess the roles of these climate-driven events. Results We present the first strongly supported molecular phylogeny for Sylvia. With one exception, species fall into one of three strongly supported clades: one small clade of species distributed mainly in Africa and Europe, one large clade of species distributed mainly in Africa and Asia, and another large clade with primarily a circum-Mediterranean distribution. Asia is reconstructed as the ancestral area for Sylvia. Long-distance migration is reconstructed as the ancestral character state for the genus, and sedentary behavior subsequently evolved seven times. Conclusion Molecular clock calibration suggests that Sylvia arose in the early Miocene and diverged into three main clades by 12.6 Ma. Divergence estimates indicate that the Messinian Salinity Crisis had a minor impact on Sylvia. Instead, over-water dispersals, repeated loss of long-distance migration, and palaeo-climatic events in Africa played primary roles in Sylvia divergence and distribution. PMID:21672229

Approaches for scalable modeling and emulation of cyber systems : LDRD final report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayo, Jackson R.; Minnich, Ronald G.; Armstrong, Robert C.

2009-09-01

The goal of this research was to combine theoretical and computational approaches to better understand the potential emergent behaviors of large-scale cyber systems, such as networks of {approx} 10{sup 6} computers. The scale and sophistication of modern computer software, hardware, and deployed networked systems have significantly exceeded the computational research community's ability to understand, model, and predict current and future behaviors. This predictive understanding, however, is critical to the development of new approaches for proactively designing new systems or enhancing existing systems with robustness to current and future cyber threats, including distributed malware such as botnets. We have developed preliminarymore » theoretical and modeling capabilities that can ultimately answer questions such as: How would we reboot the Internet if it were taken down? Can we change network protocols to make them more secure without disrupting existing Internet connectivity and traffic flow? We have begun to address these issues by developing new capabilities for understanding and modeling Internet systems at scale. Specifically, we have addressed the need for scalable network simulation by carrying out emulations of a network with {approx} 10{sup 6} virtualized operating system instances on a high-performance computing cluster - a 'virtual Internet'. We have also explored mappings between previously studied emergent behaviors of complex systems and their potential cyber counterparts. Our results provide foundational capabilities for further research toward understanding the effects of complexity in cyber systems, to allow anticipating and thwarting hackers.« less

A 1.26 μW Cytomimetic IC Emulating Complex Nonlinear Mammalian Cell Cycle Dynamics: Synthesis, Simulation and Proof-of-Concept Measured Results.

PubMed

Houssein, Alexandros; Papadimitriou, Konstantinos I; Drakakis, Emmanuel M

2015-08-01

Cytomimetic circuits represent a novel, ultra low-power, continuous-time, continuous-value class of circuits, capable of mapping on silicon cellular and molecular dynamics modelled by means of nonlinear ordinary differential equations (ODEs). Such monolithic circuits are in principle able to emulate on chip, single or multiple cell operations in a highly parallel fashion. Cytomimetic topologies can be synthesized by adopting the Nonlinear Bernoulli Cell Formalism (NBCF), a mathematical framework that exploits the striking similarities between the equations describing weakly-inverted Metal-Oxide Semiconductor (MOS) devices and coupled nonlinear ODEs, typically appearing in models of naturally encountered biochemical systems. The NBCF maps biological state variables onto strictly positive subthreshold MOS circuit currents. This paper presents the synthesis, the simulation and proof-of-concept chip results corresponding to the emulation of a complex cellular network mechanism, the skeleton model for the network of Cyclin-dependent Kinases (CdKs) driving the mammalian cell cycle. This five variable nonlinear biological model, when appropriate model parameter values are assigned, can exhibit multiple oscillatory behaviors, varying from simple periodic oscillations, to complex oscillations such as quasi-periodicity and chaos. The validity of our approach is verified by simulated results with realistic process parameters from the commercially available AMS 0.35 μm technology and by chip measurements. The fabricated chip occupies an area of 2.27 mm2 and consumes a power of 1.26 μW from a power supply of 3 V. The presented cytomimetic topology follows closely the behavior of its biological counterpart, exhibiting similar time-dependent solutions of the Cdk complexes, the transcription factors and the proteins.

Graphics enhanced computer emulation for improved timing-race and fault tolerance control system analysis. [of Centaur liquid-fuel booster

NASA Technical Reports Server (NTRS)

Szatkowski, G. P.

1983-01-01

A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.

Exploring the Model Design Space for Battery Health Management

NASA Technical Reports Server (NTRS)

Saha, Bhaskar; Quach, Cuong Chi; Goebel, Kai Frank

2011-01-01

Battery Health Management (BHM) is a core enabling technology for the success and widespread adoption of the emerging electric vehicles of today. Although battery chemistries have been studied in detail in literature, an accurate run-time battery life prediction algorithm has eluded us. Current reliability-based techniques are insufficient to manage the use of such batteries when they are an active power source with frequently varying loads in uncertain environments. The amount of usable charge of a battery for a given discharge profile is not only dependent on the starting state-of-charge (SOC), but also other factors like battery health and the discharge or load profile imposed. This paper presents a Particle Filter (PF) based BHM framework with plug-and-play modules for battery models and uncertainty management. The batteries are modeled at three different levels of granularity with associated uncertainty distributions, encoding the basic electrochemical processes of a Lithium-polymer battery. The effects of different choices in the model design space are explored in the context of prediction performance in an electric unmanned aerial vehicle (UAV) application with emulated flight profiles.

Meta-modelling, visualization and emulation of multi-dimensional data for virtual production intelligence

NASA Astrophysics Data System (ADS)

Schulz, Wolfgang; Hermanns, Torsten; Al Khawli, Toufik

2017-07-01

Decision making for competitive production in high-wage countries is a daily challenge where rational and irrational methods are used. The design of decision making processes is an intriguing, discipline spanning science. However, there are gaps in understanding the impact of the known mathematical and procedural methods on the usage of rational choice theory. Following Benjamin Franklin's rule for decision making formulated in London 1772, he called "Prudential Algebra" with the meaning of prudential reasons, one of the major ingredients of Meta-Modelling can be identified finally leading to one algebraic value labelling the results (criteria settings) of alternative decisions (parameter settings). This work describes the advances in Meta-Modelling techniques applied to multi-dimensional and multi-criterial optimization by identifying the persistence level of the corresponding Morse-Smale Complex. Implementations for laser cutting and laser drilling are presented, including the generation of fast and frugal Meta-Models with controlled error based on mathematical model reduction Reduced Models are derived to avoid any unnecessary complexity. Both, model reduction and analysis of multi-dimensional parameter space are used to enable interactive communication between Discovery Finders and Invention Makers. Emulators and visualizations of a metamodel are introduced as components of Virtual Production Intelligence making applicable the methods of Scientific Design Thinking and getting the developer as well as the operator more skilled.

Overwinter survival of neotropical migratory birds in early successional and mature tropical forests

USGS Publications Warehouse

Conway, C.J.; Powell, G.V.N.; Nichols, J.D.

1995-01-01

Many Neotropical migratory species inhabit both mature and early successional forest on their wintering grounds, yet comparisons of survival rates between habitats are lacking. Consequently, the factors affecting habitat suitability for Neotropical migrants and the potential effects of tropical deforestation on migrants are not well understood. We estimated over-winter survival and capture probabilities of Wood Thrush (Hylocichla mustelina), Ovenbird (Seiurus aurocapillus), Hooded Warbler (Wilsonia citrina), and Kentucky Warbler (Oporomis formosus) inhabiting two common tropical habitat types, mature and early-successional forest. Our results suggest that large differences (for example, ratio of survival rates (gamma) < 0.85) in overwinter survival between these habitats do not exist for any of these species. Age ratios did not differ between habitats, but males were more common in forest habitats and females more common in successional habitats for Hooded Warblers and Kentucky Warblers. Future research on overwinter survival should address the need for age- and sex-specific survival estimates before we can draw strong conclusions regarding winter habitat suitability. Our estimates of over-winter survival extrapolated to annual survival rates that were generally lower than previous estimates of annual survival of migratory birds. Capture probability differed between habitats for Kentucky Warblers, but our results provide strong evidence against large differences in capture probability between habitats for Wood Thrush, Hooded Warblers, and Ovenbirds. We found no temporal or among site differences in survival or capture probability for any of the four species. Additional research is needed to examine the effects of winter habitat use on survival during migration and between-winter survival.

The Corporation of Learning: Nonprofit Higher Education Takes Lessons from Business. Research & Occasional Paper Series. CSHE.5.03

ERIC Educational Resources Information Center

Kirp, David L.

2003-01-01

This essay examines the ways in which nonprofit universities increasingly emulate businesses, focusing on two of the most direct forms of emulation: the creation of internal university markets at the University of Southern California through adoption of variants of resource center management (RCM) and the privatization of public higher education…

Multiple plumage traits convey information about age and within-age-class qualities of a canopy-dwelling songbird, the Cerulean Warbler

USGS Publications Warehouse

Boves, Than J.; Buehler, David A.; Wood, Petra Bohall; Rodewald, Amanda D.; Larkin, Jeffrey L.; Keyser, Patrick D.; Wigley, T. Ben

2014-01-01

Colorful plumage traits in birds may convey multiple, redundant, or unreliable messages about an individual. Plumage may reliably convey information about disparate qualities such as age, condition, and parental ability because discrete tracts of feathers may cause individuals to incur different intrinsic or extrinsic costs. Few studies have examined the information content of plumage in a species that inhabits forest canopies, a habitat with unique light environments and selective pressures. We investigated the information content of four plumage patches (blue-green crown and rump, tail white, and black breast band) in a canopy-dwelling species, the Cerulean Warbler (Setophaga cerulea), in relation to age, condition, provisioning, and reproduction. We found that older males displayed wider breast bands, greater tail white, and crown and rump feathers with greater blue-green (435–534 nm) chroma and hue than males in their first potential breeding season. In turn, older birds were in better condition (short and long term) and were reproductively superior to younger birds. We propose that these age-related plumage differences (i.e. delayed plumage maturation) were not a consequence of a life history strategy but instead resulted from constraints during early feather molts. Within age classes, we found evidence to support the multiple messages hypothesis. Birds with greater tail white molted tails in faster, those with more exaggerated rump plumage (lower hue, greater blue-green chroma) provisioned more, and those with lower rump blue-green chroma were in better condition. Despite evidence of reliable signaling in this species, we found no strong relationships between plumage and reproductive performance, potentially because factors other than individual differences more strongly influenced fecundity.

Emulation and Sobol' sensitivity analysis of an atmospheric dispersion model applied to the Fukushima nuclear accident

NASA Astrophysics Data System (ADS)

Girard, Sylvain; Mallet, Vivien; Korsakissok, Irène; Mathieu, Anne

2016-04-01

Simulations of the atmospheric dispersion of radionuclides involve large uncertainties originating from the limited knowledge of meteorological input data, composition, amount and timing of emissions, and some model parameters. The estimation of these uncertainties is an essential complement to modeling for decision making in case of an accidental release. We have studied the relative influence of a set of uncertain inputs on several outputs from the Eulerian model Polyphemus/Polair3D on the Fukushima case. We chose to use the variance-based sensitivity analysis method of Sobol'. This method requires a large number of model evaluations which was not achievable directly due to the high computational cost of Polyphemus/Polair3D. To circumvent this issue, we built a mathematical approximation of the model using Gaussian process emulation. We observed that aggregated outputs are mainly driven by the amount of emitted radionuclides, while local outputs are mostly sensitive to wind perturbations. The release height is notably influential, but only in the vicinity of the source. Finally, averaging either spatially or temporally tends to cancel out interactions between uncertain inputs.

Emulating proton-induced conformational changes in the vesicular monoamine transporter VMAT2 by mutagenesis.

PubMed

Yaffe, Dana; Vergara-Jaque, Ariela; Forrest, Lucy R; Schuldiner, Shimon

2016-11-22

Neurotransporters located in synaptic vesicles are essential for communication between nerve cells in a process mediated by neurotransmitters. Vesicular monoamine transporter (VMAT), a member of the largest superfamily of transporters, mediates transport of monoamines to synaptic vesicles and storage organelles in a process that involves exchange of two H + per substrate. VMAT transport is inhibited by the competitive inhibitor reserpine, a second-line agent to treat hypertension, and by the noncompetitive inhibitor tetrabenazine, presently in use for symptomatic treatment of hyperkinetic disorders. During the transport cycle, VMAT is expected to occupy at least three different conformations: cytoplasm-facing, occluded, and lumen-facing. The lumen- to cytoplasm-facing transition, facilitated by protonation of at least one of the essential membrane-embedded carboxyls, generates a binding site for reserpine. Here we have identified residues in the cytoplasmic gate and show that mutations that disrupt the interactions in this gate also shift the equilibrium toward the cytoplasm-facing conformation, emulating the effect of protonation. These experiments provide significant insight into the role of proton translocation in the conformational dynamics of a mammalian H + -coupled antiporter, and also identify key aspects of the mode of action and binding of two potent inhibitors of VMAT2: reserpine binds the cytoplasm-facing conformation, and tetrabenazine binds the lumen-facing conformation.

Assessing the Cost of Helping: The Roles of Body Condition and Oxidative Balance in the Seychelles Warbler (Acrocephalus sechellensis)

PubMed Central

van de Crommenacker, Janske; Komdeur, Jan; Richardson, David S.

2011-01-01

In cooperatively breeding species, helping close relatives may provide important fitness benefits. However, helping can be energetically expensive and may result in increased generation of reactive oxygen species. Consequently, an oxidant/antioxidant imbalance can lead to higher oxidative stress susceptibility. Given the potential costs of helping, it may be that only individuals with a sufficiently good body condition and/or stable oxidative balance can afford to help. Knowledge about relationships between social status and oxidative balance in cooperatively breeding systems is still limited. Studying these relationships is important for understanding the costs of helping and physiological pressures of reproduction. Here we evaluate the relationship between helping behaviour, body condition and oxidative balance in a wild population of the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis). In this species, some subordinate individuals help dominant birds with the rearing of young, while others refrain from any assistance. We assessed body condition and oxidative parameters of birds of different social status caught during different breeding stages. We found that, prior to breeding, female subordinates that did not subsequently help (non-helpers) had significantly lower body condition and higher ROMs (reactive oxygen metabolites) than helpers and dominants. During the later stages of breeding, body condition was low in dominants and helpers, but high in non-helpers. Differences in oxidative balance between individuals of different social status were found only during nest care: Dominant males occupied with guarding behaviours tended to have relatively high oxidative stress susceptibility. Furthermore, dominant and helper females showed elevated antioxidant capacity (measured as OXY) in the weeks just prior to egg-laying, possibly representing a change in their reproductive physiology. The results imply that an individuals' oxidative balance may

Tree species preferences of foraging songbirds during spring migration in floodplain forests of the Upper Mississippi River

USGS Publications Warehouse

Kirsch, Eileen M.; Wellik, Mike J.

2017-01-01

Floodplain forest of the Upper Mississippi River is important for songbirds during spring migration. However, the altered hydrology of this system and spread of reed canary grass (Phalaris arundinacea) and emerald ash borer (Agrilus planipennis) threaten tree diversity and long-term sustainability of this forest. We estimated tree preferences of songbirds during spring migration 2010–2013 to help guide management decisions that promote tree diversity and forest sustainability and to evaluate yearly variation in tree selection. We used the point center-quarter method to assess relative availability of tree species and tallied bird foraging observations on tree species as well as recording the phenophase of used trees on five 40 ha plots of contiguous floodplain forest between La Crosse, Wisconsin and New Albin, Iowa, from 15 April through 1 June. We quantified bird preferences by comparing proportional use of tree species by each bird species to estimates of tree species availability for all 4 y and for each year separately. Species that breed locally preferred silver maple (Acer saccharinum), which is dominant in this forest. The common transient migrant species and the suite of 17 transient wood warbler species preferred hackberry (Celtis occidentalis) and oaks (Quercus spp.), which are limited to higher elevations on the floodplain. We observed earlier leaf development the warm springs of 2010 and 2012 and later leaf development the cold springs of 2011 and 2013. Yellow-rumped Warbler (Setophaga coronata), American Redstart (S. ruticilla), Warbling Vireo (Vireo gilvus) and Baltimore Oriole (Icterus galbula), and the suite of transient migrant wood warblers spread their foraging efforts among tree species in colder springs and were more selective in warmer springs. All three of the important tree species are not regenerating well on the UMR and widespread die-off of silver maple is possible in 50 y without large scale management.

Dynamically allocated virtual clustering management system

NASA Astrophysics Data System (ADS)

Marcus, Kelvin; Cannata, Jess

2013-05-01

The U.S Army Research Laboratory (ARL) has built a "Wireless Emulation Lab" to support research in wireless mobile networks. In our current experimentation environment, our researchers need the capability to run clusters of heterogeneous nodes to model emulated wireless tactical networks where each node could contain a different operating system, application set, and physical hardware. To complicate matters, most experiments require the researcher to have root privileges. Our previous solution of using a single shared cluster of statically deployed virtual machines did not sufficiently separate each user's experiment due to undesirable network crosstalk, thus only one experiment could be run at a time. In addition, the cluster did not make efficient use of our servers and physical networks. To address these concerns, we created the Dynamically Allocated Virtual Clustering management system (DAVC). This system leverages existing open-source software to create private clusters of nodes that are either virtual or physical machines. These clusters can be utilized for software development, experimentation, and integration with existing hardware and software. The system uses the Grid Engine job scheduler to efficiently allocate virtual machines to idle systems and networks. The system deploys stateless nodes via network booting. The system uses 802.1Q Virtual LANs (VLANs) to prevent experimentation crosstalk and to allow for complex, private networks eliminating the need to map each virtual machine to a specific switch port. The system monitors the health of the clusters and the underlying physical servers and it maintains cluster usage statistics for historical trends. Users can start private clusters of heterogeneous nodes with root privileges for the duration of the experiment. Users also control when to shutdown their clusters.

Design element alternatives for stress-management intervention websites.

PubMed

Williams, Reg A; Gatien, Gary; Hagerty, Bonnie

2011-01-01

Typical public and military-sponsored websites on stress and depression tend to be prescriptive. Some require users to complete lengthy questionnaires. Others reproduce printed flyers, papers, or educational materials not adapted for online use. Some websites require users to follow a prescribed path through the material. Stress Gym was developed as a first-level, evidence-based, website intervention to help U.S. military members learn how to manage mild to moderate stress and depressive symptoms using a self-help intervention with progress tracking and 24/7 availablility. It was designed using web-based, health-management intervention design elements that have been proven effective and users reported they prefer. These included interactivity, self-pacing, and pleasing aesthetics. Users learned how to manage stress by accessing modules they choose, and by practicing proven stress management strategies interactively immediately after login. Test results of Stress Gym with Navy members demonstrated that it was effective, with significant decreases in reported perceived stress levels from baseline to follow-up assessment. Stress Gym used design elements that may serve as a model for future websites to emulate and improve upon, and as a template against which to compare and contrast the design and functionality of future online, health-intervention websites. Copyright © 2011 Elsevier Inc. All rights reserved.

Development of landscape-level habitat suitability models for ten wildlife species in the central hardwoods region

Treesearch

Chadwick D. Rittenhouse; William D. Dijak; Frank R. III Thompson; Joshua J. Millspaugh

2007-01-01

Reports landscape-level habitat suitability models for 10 species in the Central Hardwoods Region of the Midwestern United States: American woodcock, cerulean warbler, Henslow's sparrow, Indiana bat, northern bobwhite, ruffed grouse, timber rattlesnake, wood thrush, worm-eating warbler, and yellow-breasted chat. All models included spatially explicit variables and...

Dynamical analysis of Parkinsonian state emulated by hybrid Izhikevich neuron models

NASA Astrophysics Data System (ADS)

Liu, Chen; Wang, Jiang; Yu, Haitao; Deng, Bin; Wei, Xile; Li, Huiyan; Loparo, Kenneth A.; Fietkiewicz, Chris

2015-11-01

Computational models play a significant role in exploring novel theories to complement the findings of physiological experiments. Various computational models have been developed to reveal the mechanisms underlying brain functions. Particularly, in the development of therapies to modulate behavioral and pathological abnormalities, computational models provide the basic foundations to exhibit transitions between physiological and pathological conditions. Considering the significant roles of the intrinsic properties of the globus pallidus and the coupling connections between neurons in determining the firing patterns and the dynamical activities of the basal ganglia neuronal network, we propose a hypothesis that pathological behaviors under the Parkinsonian state may originate from combined effects of intrinsic properties of globus pallidus neurons and synaptic conductances in the whole neuronal network. In order to establish a computational efficient network model, hybrid Izhikevich neuron model is used due to its capacity of capturing the dynamical characteristics of the biological neuronal activities. Detailed analysis of the individual Izhikevich neuron model can assist in understanding the roles of model parameters, which then facilitates the establishment of the basal ganglia-thalamic network model, and contributes to a further exploration of the underlying mechanisms of the Parkinsonian state. Simulation results show that the hybrid Izhikevich neuron model is capable of capturing many of the dynamical properties of the basal ganglia-thalamic neuronal network, such as variations of the firing rates and emergence of synchronous oscillations under the Parkinsonian condition, despite the simplicity of the two-dimensional neuronal model. It may suggest that the computational efficient hybrid Izhikevich neuron model can be used to explore basal ganglia normal and abnormal functions. Especially it provides an efficient way of emulating the large-scale neuron network

Subordinate females in the cooperatively breeding Seychelles warbler obtain direct benefits by joining unrelated groups.

PubMed

Groenewoud, Frank; Kingma, Sjouke A; Hammers, Martijn; Dugdale, Hannah L; Burke, Terry; Richardson, David S; Komdeur, Jan

2018-05-11

1.In many cooperatively breeding animals, a combination of ecological constraints and benefits of philopatry favours offspring taking a subordinate position on the natal territory instead of dispersing to breed independently. However, in many species individuals disperse to a subordinate position in a non-natal group ("subordinate between-group" dispersal), despite losing the kin-selected and nepotistic benefits of remaining in the natal group. It is unclear which social, genetic and ecological factors drive between-group dispersal. 2.We aim to elucidate the adaptive significance of subordinate between-group dispersal by examining which factors promote such dispersal, whether subordinates gain improved ecological and social conditions by joining a non-natal group, and whether between-group dispersal results in increased lifetime reproductive success and survival. 3.Using a long-term dataset on the cooperatively-breeding Seychelles warbler (Acrocephalus sechellensis), we investigated 4.how a suite of proximate factors (food availability, group composition, age and sex of focal individuals, population density) promote subordinate between-group dispersal by comparing such dispersers with subordinates that dispersed to a dominant position or became floaters. We then analysed whether subordinates that moved to a dominant or non-natal subordinate position, or became floaters, gained improved conditions relative to the natal territory, and compared fitness components between the three dispersal strategies. 5.We show that individuals that joined another group as non-natal subordinates were mainly female and that, similar to floating, between-group dispersal was associated with social and demographic factors that constrained dispersal to an independent breeding position. Between-group dispersal was not driven by improved ecological or social conditions in the new territory and did not result in higher survival. Instead, between-group dispersing females often became co

Improved passive optical network architectures to support local area network emulation and protection

NASA Astrophysics Data System (ADS)

Wong, Elaine; Nadarajah, Nishaanthan; Chae, Chang-Joon; Nirmalathas, Ampalavanapillai; Attygalle, Sanjeewa M.

2006-01-01

We describe two optical layer schemes which simultaneously facilitate local area network emulation and automatic protection switching against distribution fiber breaks in passive optical networks. One scheme employs a narrowband fiber Bragg grating placed close to the star coupler in the feeder fiber of the passive optical network, while the other uses an additional short length distribution fiber from the star coupler to each customer for the redirection of the customer traffic. Both schemes use RF subcarrier multiplexed transmission for intercommunication between customers in conjunction with upstream access to the central office at baseband. Failure detection and automatic protection switching are performed independently by each optical network unit that is located at the customer premises in a distributed manner. The restoration of traffic transported between the central office and an optical network unit in the event of the distribution fiber break is performed by interconnecting adjacent optical network units and carrying out signal transmissions via an independent but interconnected optical network unit. Such a protection mechanism enables multiple adjacent optical network units to be simultaneously protected by a single optical network unit utilizing its maximum available bandwidth. We experimentally verify the feasibility of both schemes with 1.25 Gb/s upstream baseband transmission to the central office and 155 Mb/s local area network data transmission on a RF subcarrier frequency. The experimental results obtained from both schemes are compared, and the power budgets are calculated to analyze the scalability of each scheme.

A pilot study comparing mouse and mouse-emulating interface devices for graphic input.

PubMed

Kanny, E M; Anson, D K

1991-01-01

Adaptive interface devices make it possible for individuals with physical disabilities to use microcomputers and thus perform many tasks that they would otherwise be unable to accomplish. Special equipment is available that purports to allow functional access to the computer for users with disabilities. As technology moves from purely keyboard applications to include graphic input, it will be necessary for assistive interface devices to support graphics as well as text entry. Headpointing systems that emulate the mouse in combination with on-screen keyboards are of particular interest to persons with severe physical impairment such as high level quadriplegia. Two such systems currently on the market are the HeadMaster and the Free Wheel. The authors have conducted a pilot study comparing graphic input speed using the mouse and two headpointing interface systems on the Macintosh computer. The study used a single subject design with six able-bodied subjects, to establish a baseline for comparison with persons with severe disabilities. Results of these preliminary data indicated that the HeadMaster was nearly as effective as the mouse and that it was superior to the Free Wheel for graphics input. This pilot study, however, demonstrated several experimental design problems that need to be addressed to make the study more robust. It also demonstrated the need to include the evaluation of text input so that the effectiveness of the interface devices with text and graphic input could be compared.

Breeding bird response to partially harvested riparian management zones

USGS Publications Warehouse

Chizinski, Christopher J.; Peterson, Anna; Hanowski, JoAnn; Blinn, Charles R.; Vondracek, Bruce C.; Niemi, Gerald

2011-01-01

We compared avian communities among three timber harvesting treatments in 45-m wide even-age riparian management zones (RMZs) placed between upland clearcuts and along one side of first- or second-order streams in northern Minnesota, USA. The RMZs had three treatments: (1) unharvested, (2) intermediate residual basal area (RBA) (targeted goal 11.5 m2/ha, realized 16.0 m2/ha), and (3) low RBA (targeted goal 5.7 m2/ha, realized 8.7 m2/ha). Surveys were conducted one year pre-harvest and three consecutive years post-harvest. There was no change in species richness, diversity, or total abundance associated with harvest but there were shifts in the types of birds within the community. In particular, White-throated Sparrows (Zonotrichia albicollis) and Chestnut-sided Warblers (Dendroica pensylvanica) increased while Ovenbirds (Seiurus aurocapilla) and Red-eyed Vireos (Vireo olivaceus) decreased. The decline of avian species associated with mature forest in the partially harvested treatments relative to controls indicates that maintaining an unharvested RMZ adjacent to an upland harvest may aid in maintaining avian species associated mature forest in Minnesota for at least three years post-harvest. However, our observations do not reflect reproductive success, which is an area for future research.

Isometric quadriceps strength determines sailing performance and neuromuscular fatigue during an upwind sailing emulation.

PubMed

Bourgois, Jan G; Callewaert, Margot; Celie, Bert; De Clercq, Dirk; Boone, Jan

2016-01-01

This study investigates the physiological responses to upwind sailing on a laser emulation ergometer and analyses the components of the physical profile that determine the physiological responses related to sailing level. Ten male high-level laser sailors performed an upwind sailing test, incremental cycling test and quadriceps strength test. During the upwind sailing test, heart rate (HR), oxygen uptake, ventilation, respiratory exchange ratio, rating of perceived exertion (RPE) and lactate concentration were measured, combined with near-infrared spectroscopy (NIRS) and electromyography (EMG) registration of the M. Vastus lateralis. Repeated measures ANOVA showed for the cardio-respiratory, metabolic and muscles responses (mean power frequency [MPF], root mean square [RMS], deoxy[Hb+Mb]) during the upwind sailing test an initial significant increase followed by a stabilisation, despite a constant increase in RPE. Stepwise regression analysis showed that better sailing level was for 46.5% predicted by lower MPF decrease. Lower MPF decrease was for 57.8% predicted by a higher maximal isometric quadriceps strength. In conclusion, this study indicates that higher sailing level was mainly determined by a lower rate of neuromuscular fatigue during the upwind sailing test (as indicated by MPF decrease). Additionally, the level of neuromuscular fatigue was mainly determined by higher maximal isometric quadriceps strength stressing the importance of resistance training in the planning of training.

Gaussian process emulators for quantifying uncertainty in CO2 spreading predictions in heterogeneous media

NASA Astrophysics Data System (ADS)

Tian, Liang; Wilkinson, Richard; Yang, Zhibing; Power, Henry; Fagerlund, Fritjof; Niemi, Auli

2017-08-01

We explore the use of Gaussian process emulators (GPE) in the numerical simulation of CO2 injection into a deep heterogeneous aquifer. The model domain is a two-dimensional, log-normally distributed stochastic permeability field. We first estimate the cumulative distribution functions (CDFs) of the CO2 breakthrough time and the total CO2 mass using a computationally expensive Monte Carlo (MC) simulation. We then show that we can accurately reproduce these CDF estimates with a GPE, using only a small fraction of the computational cost required by traditional MC simulation. In order to build a GPE that can predict the simulator output from a permeability field consisting of 1000s of values, we use a truncated Karhunen-Loève (K-L) expansion of the permeability field, which enables the application of the Bayesian functional regression approach. We perform a cross-validation exercise to give an insight of the optimization of the experiment design for selected scenarios: we find that it is sufficient to use 100s values for the size of training set and that it is adequate to use as few as 15 K-L components. Our work demonstrates that GPE with truncated K-L expansion can be effectively applied to uncertainty analysis associated with modelling of multiphase flow and transport processes in heterogeneous media.

Habitat use of two songbird species in pine-hardwood forests treated with prescribed burning and thinning: first year results

Treesearch

Jill M. Wick; Yong Wang

2010-01-01

We evaluated habitat use and home range size of hooded warblers (Wilsonia citrine) and worm-eating warblers (Helmitheros vermivorus) in six treated mixed oak-pine stands on the Bankhead National Forest in north-central AL. Study design is a randomized complete block with a factorial arrangement of three thinning levels (no thin, 11...

Numerical emulation of Thru-Reflection-Line calibration for the de-embedding of Surface Acoustic Wave devices.

PubMed

Mencarelli, D; Djafari-Rouhani, B; Pennec, Y; Pitanti, A; Zanotto, S; Stocchi, M; Pierantoni, L

2018-06-18

In this contribution, a rigorous numerical calibration is proposed to characterize the excitation of propagating mechanical waves by interdigitated transducers (IDTs). The transition from IDT terminals to phonon waveguides is modeled by means of a general circuit representation that makes use of Scattering Matrix (SM) formalism. In particular, the three-step calibration approach called the Thru-Reflection-Line (TRL), that is a well-established technique in microwave engineering, has been successfully applied to emulate typical experimental conditions. The proposed procedure is suitable for the synthesis/optimization of surface-acoustic-wave (SAW) based devices: the TRL calibration allows to extract/de-embed the acoustic component, namely resonator or filter, from the outer IDT structure, regardless of complexity and size of the letter. We report, as a result, the hybrid scattering parameters of the IDT transition to a mechanical waveguide formed by a phononic crystal patterned on a piezoelectric AlN membrane, where the effect of a discontinuity from periodic to uniform mechanical waveguide is also characterized. In addition, to ensure the correctness of our numerical calculations, the proposed method has been validated by independent calculations.

Feasibility of early functional rehabilitation in acute stroke survivors using the Balance-Bed—a technology that emulates microgravity

PubMed Central

Oddsson, Lars I. E.; Finkelstein, Marsha J.; Meissner, Sarah

2015-01-01

Evidence-based guidelines recommend early functional rehabilitation of stroke patients when risk of patient harm can be managed. Current tools do not allow balance training under load conditions sufficiently low for acute stroke patients. This single-arm pilot study tested feasibility and safety for acute stroke survivors to use “Balance-Bed”, a technology for balance exercises in supine initially developed to emulate microgravity effects on balance. Nine acute stroke patients (50–79 years) participated in 3–10 sessions over 16–46 days as part of their rehabilitation in a hospital inpatient setting. Standard inpatient measures of outcome were monitored where lack of progress from admission to discharge might indicate possible harm. Total FIM scores at admission (median 40, range 22–53) changed to (74, 50–96), Motor FIM scores from (23, 13–32) to (50, 32–68) and Berg Balance scores from (3, 0–6) to (19, 7–43) at discharge. Changes reached Minimal Clinical Important Difference for a sufficient proportion (>0.6) of the patients to indicate no harm to the patients. In addition, therapists reported the technology was safe, provided a positive experience for the patient and fit within the rehabilitation program. They reported the device should be easier to set up and exit. We conclude acute stroke patients tolerated Balance-Bed exercises such as standing on one or two legs, squats, stepping in place as well as balance perturbations provided by the therapist. We believe this is the first time it has been demonstrated that acute stroke patients can safely perform whole body balance training including balance perturbations as part of their rehabilitation program. Future studies should include a control group and compare outcomes from best practices to interventions using the Balance-Bed. In addition, the technology is relevant for countermeasure development for spaceflight and as a test-bed of balance function under microgravity-like conditions. PMID

Lean management-the journey from toyota to healthcare.

PubMed

Teich, Sorin T; Faddoul, Fady F

2013-04-01

The evolution of production systems is tightly linked to the story of Toyota Motor Company (TMC) that has its roots around 1918. The term "lean" was coined in 1990 following the exploration of the Toyota model that led to the "transference" thesis sustaining the concept that manufacturing problems and technologies are universal problems faced by management and that these concepts can be emulated in non-Japanese enterprises. Lean is a multi-faceted concept and requires organizations to exert effort along several dimensions simultaneously; some consider a successful implementation either achieving major strategic components of lean, implementing practices to support operational aspects, or providing evidence that the improvements are sustainable in the long term. The article explores challenges and opportunities faced by organizations that intend incorporating lean management principles and presents the specific context of the healthcare industry. Finally, the concepts of "essential few" and customer value are illustrated through a simple example of process change following lean principles, which was implemented in a dental school in the United States.

Migratory orientation in a narrow avian hybrid zone

PubMed Central

Toews, David P.L.; Delmore, Kira E.; Osmond, Matthew M.; Taylor, Philip D.

2017-01-01

Background Zones of contact between closely related taxa with divergent migratory routes, termed migratory divides, have been suggested as areas where hybrid offspring may have intermediate and inferior migratory routes, resulting in low fitness of hybrids and thereby promoting speciation. In the Rocky Mountains of Canada there is a narrow hybrid zone between Audubon’s and myrtle warblers that is likely maintained by selection against hybrids. Band recoveries and isotopic studies indicate that this hybrid zone broadly corresponds to the location of a possible migratory divide, with Audubon’s warblers migrating south-southwest and myrtle warblers migrating southeast. We tested a key prediction of the migratory divide hypothesis: that genetic background would be predictive of migratory orientation among warblers in the center of the hybrid zone. Methods We recorded fall migratory orientation of wild-caught migrating warblers in the center of the hybrid zone as measured by video-based monitoring of migratory restlessness in circular orientation chambers. We then tested whether there was a relationship between migratory orientation and genetic background, as measured using a set of species-specific diagnostic genetic markers. Results We did not detect a significant association between orientation and genetic background. There was large variation among individuals in orientation direction. Mean orientation was towards the NE, surprising for birds on fall migration, but aligned with the mountain valley in which the study took place. Conclusions Only one other study has directly analyzed migratory orientation among naturally-produced hybrids in a migratory divide. While the other study showed an association between genetic background and orientation, we did not observe such an association in yellow-rumped warblers. We discuss possible reasons, including the possibility of a lack of a strong migratory divide in this hybrid zone and/or methodological limitations that

Using the spatial and spectral precision of satellite imagery to predict wildlife occurrence patterns.

Treesearch

Edward J. Laurent; Haijin Shi; Demetrios Gatziolis; Joseph P. LeBouton; Michael B. Walters; Jianguo Liu

2005-01-01

We investigated the potential of using unclassified spectral data for predicting the distribution of three bird species over a -400,000 ha region of Michigan's Upper Peninsula using Landsat ETM+ imagery and 433 locations sampled for birds through point count surveys. These species, Black-throated Green Warbler, Nashville Warbler, and Ovenbird. were known to be...

Feasibility of neuro-morphic computing to emulate error-conflict based decision making.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Branch, Darren W.

2009-09-01

A key aspect of decision making is determining when errors or conflicts exist in information and knowing whether to continue or terminate an action. Understanding the error-conflict processing is crucial in order to emulate higher brain functions in hardware and software systems. Specific brain regions, most notably the anterior cingulate cortex (ACC) are known to respond to the presence of conflicts in information by assigning a value to an action. Essentially, this conflict signal triggers strategic adjustments in cognitive control, which serve to prevent further conflict. The most probable mechanism is the ACC reports and discriminates different types of feedback,more » both positive and negative, that relate to different adaptations. Unique cells called spindle neurons that are primarily found in the ACC (layer Vb) are known to be responsible for cognitive dissonance (disambiguation between alternatives). Thus, the ACC through a specific set of cells likely plays a central role in the ability of humans to make difficult decisions and solve challenging problems in the midst of conflicting information. In addition to dealing with cognitive dissonance, decision making in high consequence scenarios also relies on the integration of multiple sets of information (sensory, reward, emotion, etc.). Thus, a second area of interest for this proposal lies in the corticostriatal networks that serve as an integration region for multiple cognitive inputs. In order to engineer neurological decision making processes in silicon devices, we will determine the key cells, inputs, and outputs of conflict/error detection in the ACC region. The second goal is understand in vitro models of corticostriatal networks and the impact of physical deficits on decision making, specifically in stressful scenarios with conflicting streams of data from multiple inputs. We will elucidate the mechanisms of cognitive data integration in order to implement a future corticostriatal-like network in