WorldWideScience

Sample records for washington dc area

  1. Partners In Motion And Customer Satisfaction In The Washington Dc Metropolitan Area

    Science.gov (United States)

    1999-06-01

    PARTNERS IN MOTION IS A PROGRAM AIMED AT IMPROVING THE QUALITY, QUANTITY, AND AVAILABILITY OF TRAVEL INFORMATION TO TRANSPORTATION AGENCIES, THE MEDIA, AND, ULTIMATELY, TO THE TRAVELER IN THE WASHINGTON, D.C. METROPOLITAN AREA. THE PROGRAM WAS INITIA...

  2. Consumer behaviour in E-Commerce : Millennials in the USA, Washington D.C area

    OpenAIRE

    Torrez Pimentel, Orlando

    2016-01-01

    The target of this thesis was to understand consumer behaviour in e-commerce. The target area is the Washington DC area USA from amongst young adults between 21-34 years of age classified as millennials. The impact of technology changes and variables influencing the selection process of an e-retailer among the millennials was studied. A research with help of a survey to total 285 participants in four different shopping malls was performed in the Washington D.C. metropolitan area conducted bet...

  3. 78 FR 37104 - Establishment of Area Navigation (RNAV) Routes; Washington, DC

    Science.gov (United States)

    2013-06-20

    ... Federal Aviation Administration 14 CFR Part 71 RIN 2120-AA66 Establishment of Area Navigation (RNAV... the Federal Register approves this incorporation by reference action under 1 CFR part 51, subject to... Federal Register establishing five RNAV routes in the Washington, DC area (78 FR 29615). Subsequent to...

  4. Washington DC Metropolitan Area Drug Study Homeless and Transient Population (DC-MADST-1991)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The DC Metropolitan Area Drug Study (DCMADS) was conducted in 1991, and included special analyses of homeless and transient populations and of women delivering live...

  5. Washington DC Metropolitan Area Drug Study Household and Non-Household Populations (DC-MADSH-1991)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The DC Metropolitan Area Drug Study (DCMADS) was conducted in 1991, and included special analyses of homeless and transient populations and of women delivering live...

  6. Space Science Education and Public Outreach in the Washington, DC Area

    Science.gov (United States)

    Carruthers, G. R.; Washington, M. L.

    1999-05-01

    This paper reports on educational activities supported by the IDEAS program in the Washington, DC area. Here, we discuss activities which have been in progress over the last 5 years, which include the following: (1) development of a series of videos in space science, and associated "hands-on" activities, intended for pre-college students as supplements to their classroom education; (2) a summer teacher-training course, along the same topic outlines as (1); and (3) direct involvement of students in space science research at the Naval Research Laboratory and at Howard University's on-campus observatory. We have completed 5 chapters, with a total run time of more than 9 hours, of our proposed "Pyramids to Planets" video series in Earth and Space Science (totalling 16 chapters, of which only the space science portions are funded by IDEAS). We also plan a "stand-alone" video, "From Earth to Mars", which is a documentary of a crewed mission to Mars and return, using student "actors", which utilizes and conveys only factual information and realistic proposals for such a mission. We presented a 2-week, full-time course of study in Earth & Space Science for DC Public Schools science teachers during the summers of 1996 and 1997 (co-sponsored by the DC Space Grant Consortium). This course also introduced the teachers to the "hands-on" activities demonstrated by students in the videos. Students are directly involved, via after-school programs and summer internships, in space science activities at NRL. These include pre-launch instrument development and testing, post-launch data analysis, and education/public outreach activities for the Advanced Research and Global Observation Satellite (ARGOS) launched February 23, 1999. Students also participated in the development of two spectrographs planned for use on an existing telescope at Howard University's on-campus observatory. The facilities at this observatory are being made available for pre-college student and public use, as

  7. Trends and determinants of cycling in the Washington, DC region.

    Science.gov (United States)

    2011-01-01

    This report analyzes cycling trends, policies, and commuting in the Washington, DC area. The analysis is divided into two parts. : Part 1 focuses on cycling trends and policies in Washington (DC), Alexandria (VA), Arlington County (VA), Fairfax Count...

  8. Method development and survey of Sudan I-IV in palm oil and chilli spices in the Washington, DC, area.

    Science.gov (United States)

    Genualdi, Susie; MacMahon, Shaun; Robbins, Katherine; Farris, Samantha; Shyong, Nicole; DeJager, Lowri

    2016-01-01

    Sudan I, II, III and IV dyes are banned for use as food colorants in the United States and European Union because they are toxic and carcinogenic. These dyes have been illegally used as food additives in products such as chilli spices and palm oil to enhance their red colour. From 2003 to 2005, the European Union made a series of decisions requiring chilli spices and palm oil imported to the European Union to contain analytical reports declaring them free of Sudan I-IV. In order for the USFDA to investigate the adulteration of palm oil and chilli spices with unapproved colour additives in the United States, a method was developed for the extraction and analysis of Sudan dyes in palm oil, and previous methods were validated for Sudan dyes in chilli spices. Both LC-DAD and LC-MS/MS methods were examined for their limitations and effectiveness in identifying adulterated samples. Method validation was performed for both chilli spices and palm oil by spiking samples known to be free of Sudan dyes at concentrations close to the limit of detection. Reproducibility, matrix effects, and selectivity of the method were also investigated. Additionally, for the first time a survey of palm oil and chilli spices was performed in the United States, specifically in the Washington, DC, area. Illegal dyes, primarily Sudan IV, were detected in palm oil at concentrations from 150 to 24 000 ng ml(-1). Low concentrations (< 21 µg kg(-1)) of Sudan dyes were found in 11 out of 57 spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration.

  9. Mood sensitivity to seasonal changes in African college students living in the greater Washington D.C. metropolitan area.

    Science.gov (United States)

    Guzman, Alvaro; Rohan, Kelly J; Yousufi, Samina M; Nguyen, Minh-Chau; Jackson, Michael A; Soriano, Joseph J; Postolache, Teodor T

    2007-05-01

    The purpose of this study was to estimate the degree of seasonality and prevalence of winter- and summer-type seasonal affective disorder (SAD) in African immigrant college students in comparison with African American peers. A convenience sample of 246 African immigrants and 599 African Americans studying in Washington, D.C. completed the Seasonal Pattern Assessment Questionnaire (SPAQ), which was used to calculate a global seasonality score (GSS) and to estimate the prevalence of winter- and summer-type SAD. Degree of seasonality was related to a complex interaction between having general awareness of SAD, ethnicity, and gender. A greater percentage of African students reported experiencing a problem with seasonal changes relative to African American students, and had summer SAD, but the groups did not differ on GSS and winter SAD. African students reported more difficulties with seasonal changes than their African American peers, which could represent a manifestation of incomplete acclimatization to a higher latitude and temperate climate. As Africans also had a greater rate of summer SAD, this argues against acclimatization to heat.

  10. Mood Sensitivity to Seasonal Changes in African College Students Living in the Greater Washington D.C. Metropolitan Area

    Directory of Open Access Journals (Sweden)

    Alvaro Guzman

    2007-01-01

    Full Text Available The purpose of this study was to estimate the degree of seasonality and prevalence of winter- and summer-type seasonal affective disorder (SAD in African immigrant college students in comparison with African American peers. A convenience sample of 246 African immigrants and 599 African Americans studying in Washington, D.C. completed the Seasonal Pattern Assessment Questionnaire (SPAQ, which was used to calculate a global seasonality score (GSS and to estimate the prevalence of winter- and summer-type SAD. Degree of seasonality was related to a complex interaction between having general awareness of SAD, ethnicity, and gender. A greater percentage of African students reported experiencing a problem with seasonal changes relative to African American students, and had summer SAD, but the groups did not differ on GSS and winter SAD. African students reported more difficulties with seasonal changes than their African American peers, which could represent a manifestation of incomplete acclimatization to a higher latitude and temperate climate. As Africans also had a greater rate of summer SAD, this argues against acclimatization to heat.

  11. A Prospective Longitudinal Study of Seasonality in African Students Living in the Greater Washington, D.C. Metropolitan Area

    Directory of Open Access Journals (Sweden)

    Alvaro Guzman

    2007-01-01

    Full Text Available We conducted a prospective, longitudinal study of seasonality in a vulnerable population, i.e., African students who migrated to a temperate climate. Consistent with previous cross-sectional studies, we hypothesized lower mood and energy, and higher appetite and weight, in fall/winter than in spring/summer. Four cohorts of African students attending a year-long nursing school program without vacation in Washington, D.C., were assessed monthly for 1 year. Forty-three subjects (mean age = 33.46 ± 6.25, consisting of predominantly females (76.7%, completed the study. The cohorts began their academic program in different seasons (one each in winter, spring, summer, and fall, inherently minimizing confounding influences on seasonality, such as academic and immigration stress, as well as allowing adjustment for an order effect. At each assessment, students completed three 100-mm visual analog scales for mood, energy, and appetite, and were weighed on a digital scale. For each standardized dependent variable, a repeated measure ANOVA was used and, if a significant effect of month was identified, averages for spring/summer and fall/winter were compared using paired ttests. In addition, a mixed model for repeated measures was applied to raw (nonstandardized data. Body weight was significantly higher in fall/winter than in spring/summer (p < 0.01. No seasonal differences in mood, energy, or appetite were found. Benefiting from certain unique features of our cohorts allowing adjustment for order effects, this is the first study to identify a seasonal variation in body weight with a peak in winter using longitudinal monthly measurements.

  12. "Comets, Origins, and Life:” Promoting Interdisciplinary Science in Secondary and Middle Schools in the Washington, DC and Saint Louis, MO Metro Areas

    Science.gov (United States)

    Bonev, Boncho; Gibb, E. L.; Brewer, G.; Novak, R.; Mandell, A. M.; Seaton, P.; Price, J.; Long, T.; Bahar, S.; Edwards, S. S.

    2010-10-01

    Developing a full-year program to support secondary and middle school science education is a key part of the "broader impact” component of NSF Grant AST- 0807939 (PI/Co-PI Bonev/Gibb). This program is realized at two stages: (1) a professional development course for teachers is offered during the summer; (2) during the subsequent academic year we collaborate with educators in lessons planning or curriculum development as demanded in their particular schools. We successfully offered the course “ Comets, Origins, and Life: Interdisciplinary Science in the Secondary Classroom ” (45 contact hours; 3 credits) in the summers of 2009 and 2010 at the Catholic University of America. This class demonstrates how a complex hypothesis - for the delivery of water and prebiotic organic matter to early Earth - is being tested by integrating astronomy, physics, chemistry, biology, and Earth and planetary science. Collaborations with participants from the 2009 class include curriculum development within the Earth Science program in Prince Georges county, MD and strengthening science in Washington DC public schools. Our next step is to offer our class in the Saint Louis, MO area. The main challenge in our work with educators is not to present them with "interesting information", but to fit what we offer within the very particular curriculum expectations of their school districts. These curriculum expectations often vary from district to district and sometimes from year to year. We gratefully acknowledge the support by the NSF, allowing to fully integrate our research area into education. We also gratefully acknowledge our collaborations with the Goddard Center for Astrobiology and the Howard B. Owens Science Center (both in MD) in developing our class curriculum. Educators interested in this program can contact Boncho Bonev (bonev@cua.edu; for the Washington DC and Baltimore, MD areas) and Erika Gibb (gibbe@umsl.edu; for the Saint Louis, MO area).

  13. 77 FR 41247 - Prevailing Rate Systems; Abolishment of the Washington, DC, Special Wage Schedule for Printing...

    Science.gov (United States)

    2012-07-13

    ... Printing Positions AGENCY: U.S. Office of Personnel Management. ACTION: Interim rule with request for... Washington, DC, Federal Wage System (FWS) special wage schedule for printing and lithographic positions. Printing and lithographic employees in the Washington, DC, wage area will now be paid from the regular...

  14. Knowledge and perspectives of breast and cervical cancer screening among female African immigrants in the Washington D.C. metropolitan area.

    Science.gov (United States)

    Ndukwe, Ezinne Grace; Williams, Karen Patricia; Sheppard, Vanessa

    2013-12-01

    Black women in the USA have both a higher percentage of late-stage diagnoses as well as the highest rates of mortality from breast cancer when compared to women of other ethnic subgroups. Additionally, Black women have the second highest prevalence of cervical cancer. Many reports evaluating the cancer outcomes of Black women combine data on African-born immigrants and US-born Blacks. This categorization ignores subtle yet important cultural differences between the two groups, which may ultimately affect breast and cervical cancer screening practices. Therefore, this study investigated knowledge and awareness levels of breast and cervical cancer screening practices among female African-born immigrants to the USA residing in the Washington D.C. metropolitan area. Data were collected from 38 participants through key informant interviews, focus group sessions, and a sociodemographic questionnaire over a 3-month study period. Results suggest that fatalism, stigma, and privacy are among the major factors that affect the decision to seek preventative screening measures for breast and cervical cancer among this population. Additionally, the study implies that cervical cancer awareness is significantly lower among this population when compared to breast cancer. This study highlights differences between women of African descent residing in the USA and the need for continued research to increase understanding of the manner in which immigrant status affects health-seeking behavior. This information is critical for researchers, physicians, and public health educators aiming to design culturally appropriate interventions to effectively reduce the prevalence of breast and cervical cancer among female African immigrants living in the USA.

  15. Electronic media time and sedentary behaviors in children: Findings from the Built Environment and Active Play Study in the Washington DC area

    Directory of Open Access Journals (Sweden)

    Jennifer D. Roberts

    2017-06-01

    Full Text Available An objective of the Built Environment and Active Play (BEAP Study was to examine whether home built environment, bedroom electronic presence, parental rules and demographics predicted children's sedentary behavior (SB. In 2014, BEAP Study questionnaires were mailed to 2000 parents of children (7–12 years within the Washington DC area. SB-Duration (hours/day and SB-Frequency (days/week were assessed by two questions with multiple subparts relating to SB activity type (e.g. car riding and SB companionship (e.g. friends. Built environment, bedroom electronic presence, parental rules and demographic data were obtained through questionnaire items and ordered logistic regression models were used to examine whether these variables were associated with SB. Study sample included 144 children (female (50%; average age (9.7 years; White (56.3%; Black/African-American (23.7%; Asian-Americans (10.4%. Nearly 40% of the sample reported daily solitary SB with car riding being the most frequently reported type of SB. Children living on streets without a dead-end/cul-de-sac exhibited a higher odds in SB-Duration using electric media [2.61 (CI: 1.31, 5.18] and having no television in a child's bedroom was associated with a lower odds in SB-Frequency [0.048 (CI: 0.006, 0.393] and SB-Duration [0.085 (CI: 0.018, 0.395]. Non-Hispanic/Latino children were also found to have higher odds in solitary SB-Frequency when parental rules of electronic use were modeled [8.56 (CI: 1.11, 66.01]. Based on results from this cross-sectional study, home neighborhood built environment, bedroom electronic presence and absence of parental rules can significantly predict children's SB.

  16. Natural gas pipeline leaks across Washington, DC.

    Science.gov (United States)

    Jackson, Robert B; Down, Adrian; Phillips, Nathan G; Ackley, Robert C; Cook, Charles W; Plata, Desiree L; Zhao, Kaiguang

    2014-01-01

    Pipeline safety in the United States has increased in recent decades, but incidents involving natural gas pipelines still cause an average of 17 fatalities and $133 M in property damage annually. Natural gas leaks are also the largest anthropogenic source of the greenhouse gas methane (CH4) in the U.S. To reduce pipeline leakage and increase consumer safety, we deployed a Picarro G2301 Cavity Ring-Down Spectrometer in a car, mapping 5893 natural gas leaks (2.5 to 88.6 ppm CH4) across 1500 road miles of Washington, DC. The δ(13)C-isotopic signatures of the methane (-38.2‰ ± 3.9‰ s.d.) and ethane (-36.5 ± 1.1 s.d.) and the CH4:C2H6 ratios (25.5 ± 8.9 s.d.) closely matched the pipeline gas (-39.0‰ and -36.2‰ for methane and ethane; 19.0 for CH4/C2H6). Emissions from four street leaks ranged from 9200 to 38,200 L CH4 day(-1) each, comparable to natural gas used by 1.7 to 7.0 homes, respectively. At 19 tested locations, 12 potentially explosive (Grade 1) methane concentrations of 50,000 to 500,000 ppm were detected in manholes. Financial incentives and targeted programs among companies, public utility commissions, and scientists to reduce leaks and replace old cast-iron pipes will improve consumer safety and air quality, save money, and lower greenhouse gas emissions.

  17. Examining the Influence of a New Light Rail Line on the Health of a Demographically Diverse and Understudied Population within the Washington, D.C. Metropolitan Area: A Protocol for a Natural Experiment Study

    Directory of Open Access Journals (Sweden)

    Jennifer D. Roberts

    2018-02-01

    Full Text Available Approximately two-thirds of adults and youth in Prince George’s County, Maryland, a suburb of Washington, D.C. are overweight or obese and less than half are achieving daily physical activity recommendations. Active transportation (AT, such as walking, biking or using public transportation (PT, is a strategic pathway to improving physical activity levels and thus reducing excess weight. Utilizing an expansion of the Washington, D.C. area transportation system with a new light rail line, the Purple Line Outcomes on Transportation (PLOT Study will exam pre- and post-Purple Line PT use, AT behaviors and attitudes and physical activity among Prince George’s County adults and youth. The PLOT Study will take advantage of this natural experiment in an area enduring significant racial/ethnic and gender-based overweight or obesity and physical inactivity disparities. While similar natural experiments on AT have been conducted in other U.S. cities, those studies lacked diverse and representative samples. To effectively evaluate these physical activity outcomes among this population, efforts will be used to recruit African American and Latino populations, the first and second most common racial/ethnic groups in Prince George’s County. Finally, the PLOT Study will also examine how contextual effects (e.g., neighborhood built environment impact PT, AT and physical activity.

  18. Parks, Trees, and Environmental Justice: Field Notes from Washington, DC

    Science.gov (United States)

    Buckley, Geoffrey L.; Whitmer, Ali; Grove, J. Morgan

    2013-01-01

    Students enrolled in a graduate seminar benefited in multiple ways from an intensive 3-day field trip to Washington, DC. Constructed around the theme of environmental justice, the trip gave students a chance to learn about street tree distribution, park quality, and racial segregation "up close." Working with personnel from the United…

  19. Watershed Scale Impacts of Stormwater Green Infrastructure on Hydrology, Nitrogen Fluxes, and Combined Sewer Overflows in the Baltimore, MD and Washington, DC area

    Science.gov (United States)

    Jaffe, P. R.; Pennino, M. J.; McDonald, R.

    2016-12-01

    Despite the increasing use of urban stormwater green infrastructure (SGI), including detention ponds and rain gardens, few studies have quantified the cumulative effects of multiple SGI projects on hydrology and water quality at the watershed scale. To assess the effects of SGI, Baltimore County, MD, Montgomery County, MD, and Washington, DC, were selected based on the availability of data on SGI, water quality, and stream flow. The watershed scale impact of SGI was evaluated by assessing how increased spatial density of SGI correlates with stream hydrology and nitrogen exports over space and time. The most common SGI types were detention ponds (58%), followed by marshes (12%), sand filters (9%), wet ponds (7%), infiltration trenches (4%), and rain gardens (2%). When controlling for watersheds size and percent impervious surface cover, watersheds with greater amounts of SGI (>10% SGI) have 44% lower peak runoff, 26% less frequent runoff events, and 26% less variable runoff than watersheds with lower SGI. Watersheds with more SGI also show 44% less NO3- and 48% less total nitrogen exports compared to watersheds with minimal SGI. There was no significant reduction in combined sewer overflows in watersheds with greater SGI. Based on specific SGI types, infiltration trenches (R2 = 0.35) showed the strongest correlation with hydrologic metrics, likely due to their ability to attenuate flow, while bioretention (R2 = 0.19) and wet ponds (R2 = 0.12) showed stronger relationships with nitrogen compared to other SGI types, possibly due to greater denitrification in these sites. When comparing individual watersheds over time, increases in SGI corresponded to non-significant reductions in hydrologic flashiness and combined sewer overflows compared to watersheds with no change in SGI. This study shows that while implementation of SGI is ongoing, some regions are beginning to have enough SGI to see significant impacts on hydrology and water quality at the watershed scale.

  20. Drunk Driving. Surgeon General's Workshop. Proceedings (Washington, D.C., December 14-16, 1988).

    Science.gov (United States)

    Janus Associates.

    This volume presents solutions, recommendations, and strategies in eleven interrelated areas considered at the Surgeon General's Workshop on Drunk Driving held in Washington, D.C. in December of 1988. Lists of the members of the Workshop Planning Committee and members of the federal advisory group on follow-up activities for the workshop are…

  1. Background Air Mass Can Impact U.S. Northeastern Corridor Urban GHG Emission Analysis: A Study to Isolate Incoming CO2 Air Mass with Tower Measurements in the Washington DC/Baltimore Area

    Science.gov (United States)

    Mueller, K. L.; Lopez-Coto, I.; Yadav, V.

    2016-12-01

    City governments worldwide have made commitments to cut over 3GtCO2e above their respective national government's Nationally Determined Contributions (NDCs). To help assess the progress of such activities, atmospheric GHG observations may be vital as they contain true emission signatures. Since GHG observations contain the sum of city, regional and global sources and sinks, the city emission signal must first be isolated in the observations to render them useful for evaluating urban mitigation policies. This is especially true for regions that are downwind from large sources and sinks, such as the U.S. Northeastern corridor (NEC). Regional and global signals are generally removed through the use of tower locations that observe "background" air masses. To site these background tower locations, many urban studies use average wind directions which may not be suitable for cities in the NEC. In this work, we focus on the Washington DC/Baltimore urban area. We assume a 12 tower network that is currently being installed to quantify CO2 emissions. Using the Weather Research Forecasting model coupled to the Stochastic Time-Inverted Lagrangian Transport Model, we create synthetic observations at these 12 locations using Vulcan model sources and Carbon Tracker sinks for a 500km radius area around Washington DC/Baltimore during February and July 2013. Using these observations, we assess the impact of regional and local sources and sinks on network measurements. We then identify possible background tower locations and generate synthetic data at these sites. Using a statistical model, we select four background towers that have the greatest likelihood of capturing incoming CO2 air mass. This works shows that CO2 emission estimates for Washington DC/Baltimore will be significantly biased if the background air masses are not isolated properly. We also show that the NEC observations can be impacted by both intermediate and far field sources and sinks. The additional variability in

  2. Black Eyes and Brass Knuckles: Science Policy in Washington DC

    Science.gov (United States)

    Slakey, Francis

    2002-04-01

    Washington DC is a majestic and tranquil city, beautifully stationed along the shores of the dazzling Potomac river. Not! The nation's capitol sits in the middle of a drained swamp and it has the most hostile atmosphere this side of Venus. Francis Slakey, a professor of Physics and Biology at Georgetown University and a lobbyist for the American Physical Society, will give an intro to the political process and describe some of the battles waged on behalf of the APS.

  3. INDIAN HEAVEN ROADLESS AREA, WASHINGTON.

    Science.gov (United States)

    Church, S.E.; Barnes, D.J.

    1984-01-01

    On the basis of geologic, geochemical, and mining activity surveys the Indian Heaven Roadless Area, Washington offers little promise for the occurrence of metallic or nonmetallic mineral resources. Preliminary investigations of the geothermal potential of the area are inconclusive; however, a hot spring is located approximately 10 mi south of the roadless area, and the data indicate an aquifer of unknown extent at a temperature of less than 212 degree F. Geothermal lease applications were filed on about 23. 5 sq mi of the roadless area indicating potential interest in the development of a geothermal resource. In addition, about 39 sq mi of the roadless area have been leased for oil and gas exploration.

  4. CO2 Network Design for Washington DC/Baltimore

    Science.gov (United States)

    Lopez-Coto, I.; Prasad, K.; Ghosh, S.; Whetstone, J. R.

    2015-12-01

    The North-East Corridor project aims to use a top-down inversion method to quantify sources of Greenhouse Gas (GHG) emissions in the urban areas of Washington DC and Baltimore at approximately 1km2 resolutions. The aim of this project is to help establish reliable measurement methods for quantifying and validating GHG emissions independently of the inventory methods typically used to guide mitigation efforts. Since inversion methods depend on atmospheric observations of GHG, deploying a suitable network of ground-based measurement stations is a fundamental step in estimating emissions from the perspective of the atmosphere with reasonable levels of uncertainty. The purpose of this work is to design a tower based network of measurement stations that can reduce the uncertainty in emissions by 50% in the central areas of DC and Baltimore. To this end, the Weather Research and Forecasting Model (WRF-ARW) was used along with the Stochastic Time-Inverted Lagrangian Transport model (STILT) to derive the sensitivity of hypothetical observations to surface emissions (footprints) for the months of February and July 2013. An iterative selection algorithm, based on k-means clustering method, was applied in order to minimize the similarities between the temporal response of each site and maximize the urban contribution. Afterwards, a synthetic inversion Kalman Filter was used to evaluate the performances of the observing system based on the merit of the retrieval over time and the amount of a priori uncertainty reduced by the network. We present the performances of various measurement networks that consist of different number of towers and where the location of these towers vary. Results show that too compact networks lose spatial coverage whilst too spread networks lose capabilities of constraining uncertainties in the fluxes. In addition, we explore the possibility of using a very high density network of low-cost, low-accuracy sensors characterized by larger uncertainties and

  5. A Monumental Experience: The Undergraduate Program in Washington, DC

    Science.gov (United States)

    Betsock, Lori

    2009-08-01

    All undergraduate chemical science students are invited to attend the Undergraduate Program at the 238th ACS National Meeting in Washington, DC on August 16-17, 2009. This educational and career-oriented program is designed to increase our understanding of the world with chemistry. Symposia will focus on the chemistry of our oceans and atmosphere. Nobel Laureate Susan Solomon will be the featured Eminent Scientist speaker. Attend the Graduate School Reality Check and graduate school networking events to meet and talk with graduate school recruiters. All events will take place in the Capital Hilton (1001 16th Street NW), except for the Undergraduate Poster Session and Sci-Mix, which will be held in the Walter E. Washington Convention Center, located between 7th and 9th Streets and N Street and Mt. Vernon Place (approximately K Street).

  6. Alcohol Outlets and Violent Crime in Washington D.C.

    Directory of Open Access Journals (Sweden)

    Pan, William K

    2010-08-01

    Full Text Available Objective: Alcohol is more likely than any other drug to be involved in substance-related violence. In 2000 violence-related and self-directed injuries accounted for an estimated $37 billion and $33 billion in productivity losses and medical treatment, respectively. A review of emergency department data revealed violence and clinically identified trauma-related injuries have the strongest correlation among alcohol-dependent injuries. At the environmental level there is a relationship between alcohol outlet density and violent crime. A limited number of studies have examined the relationship between alcohol outlet type and the components of violent crime. The aim of this study is to examine the relationship between the aggregate components of violent crime and alcohol outlet density by type of outlet.Methods: For this study we used Washington, D.C. census tract data from the 2000 census to examine neighborhood characteristics. Alcohol outlet, violent crime, and population-level data for Washington, D.C. were drawn from various official yet publicly available sources. We developed an analytic database to examine the relationship between alcohol outlet category and four types of violent crime. After estimating spatial correlation and determining spatial dependence, we used a negative binomial regression analysis to assess the alcohol availability-violent crime association, while controlling for structural correlates of violence.Results: Independent of alternative structural correlates of violent crime, including the prevalence of weapons and illicit drugs, community-level alcohol outlet density is significantly associated with assaultive violence. Outlets were significantly related to robbery, assault, and sexual offenses. In addition, the relationship among on-premise and off-premise outlets varied across violent crime categories.Conclusion: In Washington, D.C., alcohol outlet density is significantly associated with the violent crimes. The

  7. Facing the Rising Sun: A History of Black Educators in Washington, DC, 1800-2008

    Science.gov (United States)

    Frederick, Rona M.; View, Jenice L.

    2009-01-01

    Over 50 years after the monumental decision of "Brown v. Board of Education," many U.S. schools remain separate and unequal. This includes schools in the nation's capital, Washington, D.C. The article discusses how in the two centuries of public education in Washington, D.C., Black educators used a variety of subversive tactics to…

  8. Ocular findings in human immunodeficiency virus patients in Washington, DC.

    Science.gov (United States)

    Kaleem, Mona A; Ramsahai, Shweta; Del Fierro, Katrina; Rasul, Samad; Onumah, Chavon; Lerebours, Valerie; Gajjala, Jhansi; Copeland, Robert A; Jones, Leslie S

    2012-04-01

    The purpose of the study was to determine the prevalence of ocular diseases in human immunodeficiency virus (HIV) patients in Washington, DC in the era of highly active antiretroviral therapy (HAART). This was a cross-sectional study of patients with HIV who were seen by the ophthalmology consultation service between September 2003 and May 2011 at a single academic institution in Washington, DC. Medical history and ophthalmic findings were reviewed. Patients with complete laboratory data dated within 3 months of their presenting eye examination were included. Descriptive statistics were performed. The records of 151 patients were included in the final analysis. All patients had complete laboratory data dated within 3 months of their presenting eye examination. Sixty-eight (45 %) patients and fifty-eight (50 %) of those with a diagnosis of acquired immune deficiency syndrome (AIDS) were diagnosed with an HIV-related ophthalmic disease. The leading anterior segment disease was herpes zoster ophthalmicus and the leading posterior segment disease was HIV retinopathy. Of the 151 included patients, 78 (52 %) were receiving HAART at the time of the examination. Thirty-one (42 %) of those not receiving HAART were diagnosed with an HIV-related ophthalmic disease. In this study, we find that the overall prevalence of ocular disease has decreased since the introduction of HAART. However, HIV patients continue to be predisposed to developing ophthalmic disease at higher rates than the general population. Visual dysfunction remains an important source of morbidity in HIV patients, particularly in those with AIDS. Measures for improvement include increased communication between infectious disease specialists and ophthalmologists to ensure adherence to HAART and routine eye examinations.

  9. Effects of Washington, D.C. law on drivers' hand-held cell phone use.

    Science.gov (United States)

    McCartt, Anne T; Hellinga, Laurie A; Geary, Lori L

    2006-03-01

    To assess the effects of Washington, D.C. law prohibiting drivers' use of hand-held cell phones on such use. Daytime observations of drivers were conducted at signalized intersections in D.C. in March 2004, several months before the law took effect on July 1, 2004, and again in October 2004. As a comparison, observations also were conducted in areas of Virginia and Maryland located close to the D.C. border. Maryland and Virginia placed no limitations on drivers' phone use. Use was observed for 36,091 vehicles in D.C., 25,151 vehicles in Maryland, and 28,483 vehicles in Virginia. The rate of talking on hand-held cell phones among drivers in D.C. declined significantly from 6.1% before the law to 3.5% after. Phone use declined slightly in Maryland and increased significantly in Virginia so that, relative to the patterns of hand-held phone use in the two states, phone use in D.C. declined 50%. Hand-held phone use in D.C. declined comparably among drivers of vehicles registered in all three jurisdictions. D.C. police issued 2,556 citations and 1,232 warnings for cell phone violations during July-November 2004. There were spates of media coverage when the law was passed and when it took effect. D.C.'s law prohibiting drivers' hand-held phone use had a strong effect on such use among drivers in D.C. Without ongoing publicized enforcement of the law, long-term compliance may be difficult to achieve.

  10. The Politics of Inclusion: A Case Study of the Violence Against Women Act & Foreign Born Latinas in Washington, DC"

    OpenAIRE

    Garcia, Olivia

    2014-01-01

    This dissertation asks: How does the Violence Against Women Act (VAWA) impact Latinas in the Washington, DC area? My research focuses on the Violence Against Women Act and the ways in which the theory of intersectionality is absent from policy, although it is a necessary consideration when on-the-ground advocates are helping foreign-born, Latina, immigrant victims of intimate partner violence. I contend that Washington, DC is a new region for Latino/a communities and that Latinas are less lik...

  11. Tree canopy change and neighborhood stability: A comparative analysis of Washington, D.C. and Baltimore, MD

    Science.gov (United States)

    Wen-Ching Chuang; Christopher G. Boone; Dexter H. Locke; J. Morgan Grove; Ali Whitmer; Geoffrey Buckley; Sainan Zhang

    2017-01-01

    Trees provide important health, ecosystem, and aesthetic services in urban areas, but they are unevenly distributed. Some neighborhoods have abundant tree canopy and others nearly none. We analyzed how neighborhood characteristics and changes in income over time related to the distribution of urban tree canopy in Washington, D.C. and Baltimore, MD. We used stepwise...

  12. Geologic map of the Washington West 30’ × 60’ quadrangle, Maryland, Virginia, and Washington D.C.

    Science.gov (United States)

    Lyttle, Peter T.; Aleinikoff, John N.; Burton, William C.; Crider, E. Allen; Drake, Avery A.; Froelich, Albert J.; Horton, J. Wright; Kasselas, Gregorios; Mixon, Robert B.; McCartan, Lucy; Nelson, Arthur E.; Newell, Wayne L.; Pavlides, Louis; Powars, David S.; Southworth, C. Scott; Weems, Robert E.

    2018-01-02

    The Washington West 30’ × 60’ quadrangle covers an area of approximately 4,884 square kilometers (1,343 square miles) in and west of the Washington, D.C., metropolitan area. The eastern part of the area is highly urbanized, and more rural areas to the west are rapidly being developed. The area lies entirely within the Chesapeake Bay drainage basin and mostly within the Potomac River watershed. It contains part of the Nation's main north-south transportation corridor east of the Blue Ridge Mountains, consisting of Interstate Highway 95, U.S. Highway 1, and railroads, as well as parts of the Capital Beltway and Interstate Highway 66. Extensive Federal land holdings in addition to those in Washington, D.C., include the Marine Corps Development and Education Command at Quantico, Fort Belvoir, Vint Hill Farms Station, the Naval Ordnance Station at Indian Head, the Chesapeake and Ohio Canal National Historic Park, Great Falls Park, and Manassas National Battlefield Park. The quadrangle contains most of Washington, D.C.; part or all of Arlington, Culpeper, Fairfax, Fauquier, Loudoun, Prince William, Rappahannock, and Stafford Counties in northern Virginia; and parts of Charles, Montgomery, and Prince Georges Counties in Maryland.The Washington West quadrangle spans four geologic provinces. From west to east these provinces are the Blue Ridge province, the early Mesozoic Culpeper basin, the Piedmont province, and the Coastal Plain province. There is some overlap in ages of rocks in the Blue Ridge and Piedmont provinces. The Blue Ridge province, which occupies the western part of the quadrangle, contains metamorphic and igneous rocks of Mesoproterozoic to Early Cambrian age. Mesoproterozoic (Grenville-age) rocks are mostly granitic gneisses, although older metaigneous rocks are found as xenoliths. Small areas of Neoproterozoic metasedimentary rocks nonconformably overlie Mesoproterozoic rocks. Neoproterozoic granitic rocks of the Robertson River Igneous Suite intruded

  13. Spacelab being closed up for move to Washington, DC

    Science.gov (United States)

    1998-01-01

    A closeup view of the hatch to this Spacelab module shows an empty interior as the module is being prepared in the Operations & Checkout Building for shipment to the National Air and Space Museum in Washington, DC. Visible on the floor are the foot restraints used by astronauts to keep them stationary while conducting experiments. Spacelab was designed by the European Space Agency (ESA) for the Space Shuttle program. It first flew on STS-9 in November 1983 and its final flight was the STS-90 Neurolab mission in April 1998. The Spacelab concept of modular experiment racks in a pressurized shirt-sleeve environment made it highly user-friendly and accessible. Numerous experiments conceived by hundreds of scientists on the ground were conducted by flight crews in orbit. Spacelab modules served as on-orbit homes for everything from squirrel monkeys to plant seeds. They supported astronomical as well as Earth observations, for servicing the Hubble Space Telescope and for research preparatory to the International Space Station. One of the greatest benefits afforded by the Spacelab missions was the opportunity to fly a mission more than once, with the second or third flight building on the experiences and data gathered from its predecessors.

  14. Prediction and impact of sea level rise on properties and infrastructure of Washington, DC.

    Science.gov (United States)

    Ayyub, Bilal M; Braileanu, Haralamb G; Qureshi, Naeem

    2012-11-01

    The city of Washington, District of Columbia (DC) will face flooding, and eventual geographic changes, in both the short- and long-term future because of sea level rise (SLR) brought on by climate change, including global warming. To fully assess the potential damage, a linear model was developed to predict SLR in Washington, DC, and its results compared to other nonlinear model results. Using geographic information systems (GIS) and graphical visualization, analytical models were created for the city and its underlying infrastructure. Values of SLR used in the assessments were 0.1 m for the year 2043 and 0.4 m for the year 2150 to model short-term SLR; 1.0 m, 2.5 m, and 5.0 m were used for long-term SLR. All necessary data layers were obtained from free data banks from the U.S. Geological Survey and Washington, DC government websites. Using GIS software, inventories of the possibly affected infrastructure were made at different SLR. Results of the analysis show that low SLR would lead to a minimal loss of city area. Damages to the local properties, however, are estimated at an assessment value of at least US$2 billion based on only the direct losses of properties listed in real estate databases, without accounting for infrastructure damages that include military installations, residential areas, governmental property, and cultural institutions. The projected value of lost property is in excess of US$24.6 billion at 5.0 m SLR. © 2011 Society for Risk Analysis.

  15. Washington D.C. Lightning Mapping Array Demonstration Project Risk Reduction for GOES Lightning Mapper Data

    Science.gov (United States)

    Smith, Stephan B.; Goodman, Steven; Krehbiel, Paul

    2007-01-01

    A 10-site, ground-based total lightning mapping array (LMA) has been installed in the Washington D.C. metropolitan area in 2006. The total lightning data from DC LMA are being processed in real-time and derived products are being provided to the forecasters of the National Weather Service (NWS) forecast office in Sterling, Virginia. The NWS forecasters are using the products to monitor convective activity along with conventional radar and satellite products. Operational experience with these products is intended to inform decision making in how to best utilize in NWS operations similar data available from the GOES Lightning Mapper. The paper will discuss specifics of the LMA as well as proposed research into use of total lightning data in predicting and warning for cloud-to-ground lightning.

  16. National Conference on New Juvenile Justice Standards, Washington, D.C., 1977

    Science.gov (United States)

    Ter Haar, Alice C.

    1978-01-01

    Describes the standards on rights of minors, abuse and neglect, non-criminal behavior, and schools and education which were adopted at the National Conference on New Juvenile Justice Standards, Washington, D.C., 1977. (Author)

  17. 78 FR 1 - Prevailing Rate Systems; Abolishment of the Washington, DC, Special Wage Schedule for Printing...

    Science.gov (United States)

    2013-01-02

    ... Printing Positions AGENCY: U.S. Office of Personnel Management. ACTION: Correcting amendment. SUMMARY: The..., 2012, abolishing the Washington, DC, Federal Wage System special wage schedule for printing and...

  18. Availability of Network Psychiatrists Among the Largest Health Insurance Carriers in Washington, D.C.

    Science.gov (United States)

    Blech, Benzion; West, Joyce C; Yang, Zhuoyin; Barber, Keila D; Wang, Philip; Coyle, Colleen

    2017-09-01

    Lack of access to mental health treatment remains a significant problem in the United States, even after implementation of mental health parity legislation. This study examined availability of psychiatrists listed in insurance carrier network provider databases in the Washington, D.C., area. Contact information was obtained for 1,184 psychiatrists listed in online directories for three of the largest insurance carriers serving the Washington, D.C., area. The "mystery shopper" method was used to assess the accuracy of listed contact information, new outpatient appointment availability, and average wait times for 50 psychiatrists randomly selected from each insurance directory. Most (77%) physicians were successfully contacted, meaning that someone answered the phone or returned a voice mail message, and 51% of the psychiatrists had working telephone numbers verified to be correct. Fifteen percent of the psychiatrists were accepting new outpatients with the target insurance, with average wait times of 19 days; only 7% were able to schedule an appointment within two weeks. Inaccuracy of insurance provider directories significantly affected the ability of patients to obtain timely mental care.

  19. DNA Barcoding analysis of seafood accuracy in Washington, D.C. restaurants

    Science.gov (United States)

    Stern, David B.; Castro Nallar, Eduardo; Rathod, Jason

    2017-01-01

    In Washington D.C., recent legislation authorizes citizens to test if products are properly represented and, if they are not, to bring a lawsuit for the benefit of the general public. Recent studies revealing the widespread phenomenon of seafood substitution across the United States make it a fertile area for consumer protection testing. DNA barcoding provides an accurate and cost-effective way to perform these tests, especially when tissue alone is available making species identification based on morphology impossible. In this study, we sequenced the 5′ barcoding region of the Cytochrome Oxidase I gene for 12 samples of vertebrate and invertebrate food items across six restaurants in Washington, D.C. and used multiple analytical methods to make identifications. These samples included several ambiguous menu listings, sequences with little genetic variation among closely related species and one sequence with no available reference sequence. Despite these challenges, we were able to make identifications for all samples and found that 33% were potentially mislabeled. While we found a high degree of mislabeling, the errors involved closely related species and we did not identify egregious substitutions as have been found in other cities. This study highlights the efficacy of DNA barcoding and robust analyses in identifying seafood items for consumer protection. PMID:28462038

  20. A Topographic Field Trip of Washington, D.C. - A Cartographic Multimedia Application

    Science.gov (United States)

    ,

    1999-01-01

    The U.S. Geological Survey (USGS) has produced ?A Topographic Field Trip of Washington, D.C.,' a multimedia CD-ROM that uses topographic maps to tour Washington, D.C. Although designed for the middle school grade level, it can also be used to teach introductory topographic map reading skills to any level. Two versions of ?A Topographic Field Trip of Washington, D.C.,? are available. The first version, for Macintosh? systems only, was developed and produced as a prototype with educational resources funds and is available free of charge. The second version, for dual platforms, Macintosh?, and Windows? systems, is a sales item. The dual platform version contains improvements in content and navigational capabilities.

  1. The Washington Large Area Time Coincidence Array

    Science.gov (United States)

    Gran, R.; Berns, H.G.; Buchli, M.; Burnett, T.H.; Edmon, P.; Gran, R.; Haff, T.; Lemagie; Muhs, E.; Wheel, G.; Wilkes, R.J.

    2003-07-01

    WALTA (WAshington Large-area Time-coincidence Array) aims to study ultra-high energy (> 1018 eV) cosmic rays (UHECR) by placing detector elements in Seattle area secondary scho ols, and linking their data acquisition systems to the University of Washington via a computer network. The goal of WALTA is to have teachers and students become active participants in forefront scientific project, while building a long term partnership between the scho ols and the university-based physics research community. Considerable progress has been made in recruiting and training teachers and equipping scho ol sites since the last ICRC, including development of a low-cost data acquisition card in collab oration with Fermilab and the University of Nebraska.

  2. The hydrogeology of urbanization: The lost springs of Washington, D.C., late Tertiary and Quaternary sediments of D.C., and the Baltimore Long Term Ecological Research site (LTER): Chapter

    Science.gov (United States)

    Bhaskar, Aditi; Pavich, Milan J.; Sharp, John M.

    2015-01-01

    Urbanization is a major process now shaping the environment. This field trip looks at the hydrogeology of the general Washington, D.C., area and focuses on the city's lost springs. Until 150 years ago, springs and shallow dug wells were the main source of drinking water for residents of Washington, D.C. Celebrating the nation's bicentennial, Garnett P. Williams of the U.S. Geological Survey examined changes in water supply and water courses since 1776. He examined old newspaper files to determine the location of the city's springs. This field trip visits sites of some of these springs (few of which are now flowing), discusses the hydrologic impacts of urbanization and the general geological setting, and finishes with the Baltimore Long Term Ecological Research site at Dead Run and its findings. The field trip visits some familiar locations in the Washington, D.C., area, and gives insights into their often hidden hydrologic past and present.

  3. Sidwell Friends Quaker School, Washington, DC, by KieranTimberlake Architects

    DEFF Research Database (Denmark)

    Vibæk, Kasper Sánchez; Stylsvig Madsen, Ulrik

    2012-01-01

    In 2006 the new Middle School Building on the campus of Sidwell Friends School in Washington DC was completed at a cost of $28 million. The project is a renovation and addition to a fifty-year-old educational facility transforming the building and the surrounding landscape into a green expression...

  4. Groundwater Site Identification Indexes for Washington D.C., Baltimore City, and the Counties of Maryland

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data sets represent 23 geographic 5-minute indexes for the counties of Maryland, one 2 1/2-minute index for Washington D.C., and 1-mile square index for...

  5. Enjoying green cities: Assessing visitors' attitude and preferences of urban forests in Washington, D.C.

    Science.gov (United States)

    Rogelio II Andrada; Jinyang. Deng

    2012-01-01

    This study examined the attitudes and preferences of visitors toWashington, D.C., one of the top tourism cities in the United States. Results of a visitor survey conducted at two sites show that respondents have a highly positive attitude towards the city's urban forest and that their appreciation of the urban forest has a positive influence on their experiences...

  6. Assessment of Public Health Risks Associated with Atmospheric Exposure to PM2.5 in Washington, DC, USA

    Directory of Open Access Journals (Sweden)

    Vernon R. Morris

    2006-03-01

    Full Text Available In this research, we investigated the public health risks associated with atmospheric exposure to PM2.5 for different subpopulations (black, white, Hispanic, youth, adults, and elderly in the Washington, DC area. Washington, DC has long been considered a non-healthy place to live according to the American Lung Association due to its poor air quality. This recognition clearly includes the negative PM-related human health effects within the region. Specifically, DC fine particulate matter (PM2.5 [or particulate matter with an aerodynamic diameter less than 2.5 μm] poses notable health risks to subpopulations having an annual mean value of 16.70 μg/m3 during the years 1999-2004, exceeding the EPA National Ambient Air Quality Standard (NAAQS of 15 μg/m3. Incessant exposure to significant levels of PM has previously been linked to deleterious health effects, such as heart and lung diseases. The environmental quality and public health statistics of Washington, DC indicate the need for higher-resolution measurements of emissions, both spatially and temporally, and increased analysis of PM-related health effects. Our findings show that there are significant risks of ward-specific pediatric asthma emergency room visits (ERV. Results also illustrate lifetime excess lung cancer risks, exceeding the 1x10-6 threshold for the measured levels of particulate matter and heavy metals (chromium and arsenic on behalf of numerous subpopulations in the DC selected wards.

  7. Vouchers escolares y justicia social: evidencia de Washington, DC

    OpenAIRE

    Wolf, Patrick J.; Boccardo, Jessica

    2011-01-01

    El Programa de Becas de Oportunidad del Distrito de Columbia (OSP) es una iniciativa de vales o vouchers escolares dirigidos a los estudiantes más necesitados en la capital de EEUU. Los vouchers, con un valor de hasta $ 7,500 al año, son otorgados por medio de una lotería a los estudiantes con ingresos familiares cerca o por debajo del umbral de pobreza federal. Los estudiantes pueden usar sus vouchers en cualquiera de las 60 escuelas privadas participantes en DC. La pregunta que surge es: ...

  8. An Urban Soccer Stadium for Washington D.C.

    OpenAIRE

    Ard, John Christopher

    2014-01-01

    Expansive parking lots, miles of asphalt, and traffic jams: this is what the modern sport stadia has come to represent. Does it have to be this way? What does the future of sports stadia hold? Can we build a stadium that is better integrated to the community around it? The stadium must become a major urban element again and it must engage the urban context. D.C. United, the most storied franchise in MLS history, needs a new home. Baltimore and other locations in Maryland would gladly we...

  9. Urban and Suburban Influences on Water Chemistry in Washington DC: Impervious Surfaces and Urban Stream Syndrome

    Science.gov (United States)

    MacAvoy, S. E.; Petersen, E.

    2015-12-01

    Among the challenges facing urban rivers are water stormwater runoff problems and changing water chemistry, not only from air and water pollution sources, but also from altered geology with the development of "urban karst". Seventy five percent of the Anacostia River in Washington, D.C. is urban or impervious. The Anacostia River experiences environmental challenges similar to those of other urban industrial rivers (heavy metal, PCB and PAH contamination). It also has Ca/Sr ratios above 200, and Na concentrations higher than Ca, and elevated ionic strength, all associated with extended chemical interaction with concrete. While these chemical characteristics have been documented in the urban areas within DC, they have not been examined in the largely suburban/mixed development tributaries of the Anacostia. Here we examine the base-flow geochemistry of the Anacostia River and its suburban tributaries (6 locations) over a year (November 2014- August 2015), concentrating on the following water chemistry variables: pH, hardness, SAR, alkalinity, Ca, Mg, Na, K, Fe, Mn, Zn, Al, Ba, Ni, total P, S, Sr, NO3-, NH4+, PO43-. NO3- and NH4+ were generally lowest in at all sites in January, but rose to between 0.5 and 2.4 mg/L in June, with highest NO3- concentrations in suburban areas. Na and Cl concentrations were 5x higher in suburban areas than urban areas during the winter months. Ca/Sr concentration ratios, were between 120 and 200 for suburban sites but increased as the sites became more urban (to a high of 240 for the most urban site). These trends have been observed in other urban streams, and correlate with percent impervious area. The data follow patterns expected for "urban stream syndrome" and dissolution of concrete. Suburban areas, with their relatively small streams, show greater winter salting effects than more urban areas down stream. Suburban areas also show higher NO3- (and occasionally higher NH4+) than urban areas except in winter. The data presented here

  10. Social Marketing and the "New" Technology: Proceedings of a Washington Roundtable (Washington, DC, March 25, 1998).

    Science.gov (United States)

    Academy for Educational Development, Washington, DC.

    This document examines some of the key issues raised during the second Washington Roundtable on Social Marketing, convened by the Academy for Educational Development (AED) in 1998. AED invited participants to examine whether the interactive technologies that are revolutionizing commercial marketing--personal computers, the Internet (especially the…

  11. Modeling the effect of transient populations on epidemics in Washington DC

    Science.gov (United States)

    Parikh, Nidhi; Youssef, Mina; Swarup, Samarth; Eubank, Stephen

    2013-11-01

    Large numbers of transients visit big cities, where they come into contact with many people at crowded areas. However, epidemiological studies have not paid much attention to the role of this subpopulation in disease spread. We evaluate the effect of transients on epidemics by extending a synthetic population model for the Washington DC metro area to include leisure and business travelers. A synthetic population is obtained by combining multiple data sources to build a detailed minute-by-minute simulation of population interaction resulting in a contact network. We simulate an influenza-like illness over the contact network to evaluate the effects of transients on the number of infected residents. We find that there are significantly more infections when transients are considered. Since much population mixing happens at major tourism locations, we evaluate two targeted interventions: closing museums and promoting healthy behavior (such as the use of hand sanitizers, covering coughs, etc.) at museums. Surprisingly, closing museums has no beneficial effect. However, promoting healthy behavior at the museums can both reduce and delay the epidemic peak. We analytically derive the reproductive number and perform stability analysis using an ODE-based model.

  12. Brief research report: sociodemographic factors associated with HIV status among African American women in Washington, DC

    Directory of Open Access Journals (Sweden)

    Perkins EL

    2013-09-01

    Full Text Available Emory L Perkins,1 Dexter R Voisin,2 Kesslyn A Brade Stennis1 1Department of Social Work, Bowie State University, Bowie, MD, USA; 2School of Social Service Administration, University of Chicago, Chicago, IL, USA Introduction: African American women living in Washington, DC have one of the highest Human immunodeficiency virus (HIV incidence rates in the US. However, this population has been understudied, especially as it relates to factors associated with HIV status. Methods: This cross-sectional study examined sociodemographic factors that were associated with having a negative or positive HIV status among a sample of 115 African American women between the ages of 24 and 44 years. We assessed such factors as age, education, sexual orientation, household income, sources of income, number of children, length of residency tenure in Washington, DC, and level of HIV-prevention knowledge. Results: Among the overall sample, 53 women self-identified as HIV-positive and 62 as HIV-negative. Compared to their HIV-negative counterparts, women who reported being HIV-positive were less educated, had lower household income, and had longer residency tenure in Washington, DC. There were no differences in HIV knowledge between HIV-positive and -negative study participants. Conclusion: These findings may provide important directions for targeting specific subpopulations of African Americans for HIV-prevention/intervention programs. Keywords: HIV status, African American women, sociodemographic factors

  13. Can learning in informal settings mitigate disadvantage and promote urban sustainability? School gardens in Washington, DC

    Science.gov (United States)

    Fisher-Maltese, Carley; Fisher, Dana R.; Ray, Rashawn

    2017-09-01

    This article explores how school gardens provide learning opportunities for school-aged children while concurrently helping cities achieve sustainability. The authors analyse this process in Washington, DC, a particularly innovative metropolis in the United States. This national capital city boasts two of the most progressive examples of legislation aimed at improving environmental awareness and inciting citizens to engage in environmental stewardship, both of which focus on school-aged children: (1) the Healthy Schools Act of 2010 and (2) the Sustainable DC Act of 2012. Together these policies focus on bringing healthy lifestyles and environmental awareness, including meaningful outdoor learning experiences, to students and families in the District of Columbia. This article is organised into three parts. The first part discusses how Washington, DC became a sustainable learning city through the implementation of these specific policies. The next part presents the results of a pilot study conducted in one kindergarten to Grade 5 (K-5) elementary school located in Ward 8, the poorest part of the city. The authors' analysis considers the support and the obstacles teachers and principals in the District of Columbia (DC) are experiencing in their efforts to integrate school gardens into the curriculum and the culture of their schools. Exploring the impacts of the school garden on the students, the local community, and the inter-generational relationships at and beyond schools, the authors aim to shed light on the benefits and the challenges. While Washington, DC is fostering its hope that the benefits prevail as it provides a model for other cities to follow, the authors also candidly present the challenges of implementing these policies. In the final part, they discuss the implications of their findings for school gardens and sustainable learning cities more broadly. They encourage further research to gain more insights into effective ways of promoting environmental

  14. Residential Energy Efficiency Research Planning Meeting Summary Report: Washington, D.C. - October 27-28, 2011

    Energy Technology Data Exchange (ETDEWEB)

    2012-02-01

    This report summarizes key findings and outcomes from the U.S. Department of Energy's Building America Residential Energy Efficiency Research Planning meeting, held on October 28-29, 2011, in Washington, D.C.

  15. Weatherization Program is a Capital Idea for Washington, D.C.: Weatherization Assistance Close-Up Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    D& R International

    2001-10-10

    Washington, D.C. demonstrates its commitment to technology and efficiency through the Weatherization Program. Weatherization uses advanced technologies and techniques to reduce energy costs for low-income families by increasing the energy efficiency of their homes.

  16. Energy Savings Analysis of the Proposed Revision of the Washington D.C. Non-Residential Energy Code

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Michael I.; Athalye, Rahul A.; Hart, Philip R.

    2017-12-01

    This report presents the results of an assessment of savings for the proposed Washington D.C. energy code relative to ASHRAE Standard 90.1-2010. It includes annual and life cycle savings for site energy, source energy, energy cost, and carbon dioxide emissions that would result from adoption and enforcement of the proposed code for newly constructed buildings in Washington D.C. over a five year period.

  17. Parental perceived built environment measures and active play in Washington DC metropolitan children.

    Science.gov (United States)

    Roberts, Jennifer D; Knight, Brandon; Ray, Rashawn; Saelens, Brian E

    2016-06-01

    Previous research identified associations between perceived built environment and adult physical activity; however, fewer studies have explored associations in children. The Built Environment and Active Play (BEAP) Study examined relationships between children's active play and parental perceptions of home neighborhood built environments within the Washington, DC metropolitan area (DMV). With this cross-sectional study, a questionnaire was administered in 2014 to parents of children (7-12 years old) residing in the DMV. Data were collected on children's active play, home built environment parental perceptions, and demographics. Active play response data were dichotomized by whether the child did or did not meet the 60-min/day Physical Activity Guidelines for Americans (PAGAs) recommendation. Perceived home neighborhood built environment data were also dichotomized. Chi-square tests determined differences in parental perceived built environment measures between active and non-active child groups. Logistic regression assessed the association of parental perceived built environment variables with active play while adjusting for demographic variables. The BEAP Study population (n = 144) included a uniquely diverse population of children with 23.7% African Americans and 10.4% Asian Americans. A statistically significant greater proportion of active children's parents agreed with the importance of neighborhood esthetics, active play areas, walkability and safety as compared to the parents of non-active children. Fully adjusted logistic regression models demonstrated that some parental perceived built environment measures (e.g. access to play equipment) were predictors of their children meeting the 60-min/day PAGA recommendation. Our findings support the important role of home neighborhood built environment perceptions on childhood active play.

  18. Building-Resolved CFD Simulations for Greenhouse Gas Transport and Dispersion over Washington DC / Baltimore

    Science.gov (United States)

    Prasad, K.; Lopez-Coto, I.; Ghosh, S.; Mueller, K.; Whetstone, J. R.

    2015-12-01

    The North-East Corridor project aims to use a top-down inversion methodology to quantify sources of Greenhouse Gas (GHG) emissions over urban domains such as Washington DC / Baltimore with high spatial and temporal resolution. Atmospheric transport of tracer gases from an emission source to a tower mounted receptor are usually conducted using the Weather Research and Forecasting (WRF) model. For such simulations, WRF employs a parameterized turbulence model and does not resolve the fine scale dynamics generated by the flow around buildings and communities comprising a large city. The NIST Fire Dynamics Simulator (FDS) is a computational fluid dynamics model that utilizes large eddy simulation methods to model flow around buildings at length scales much smaller than is practical with WRF. FDS has the potential to evaluate the impact of complex urban topography on near-field dispersion and mixing difficult to simulate with a mesoscale atmospheric model. Such capabilities may be important in determining urban GHG emissions using atmospheric measurements. A methodology has been developed to run FDS as a sub-grid scale model within a WRF simulation. The coupling is based on nudging the FDS flow field towards that computed by WRF, and is currently limited to one way coupling performed in an off-line mode. Using the coupled WRF / FDS model, NIST will investigate the effects of the urban canopy at horizontal resolutions of 10-20 m in a domain of 12 x 12 km. The coupled WRF-FDS simulations will be used to calculate the dispersion of tracer gases in the North-East Corridor and to evaluate the upwind areas that contribute to tower observations, referred to in the inversion community as influence functions. Results of this study will provide guidance regarding the importance of explicit simulations of urban atmospheric turbulence in obtaining accurate estimates of greenhouse gas emissions and transport.

  19. Modeling Storm Surge and Inundation in Washington, DC, during Hurricane Isabel and the 1936 Potomac River Great Flood

    Directory of Open Access Journals (Sweden)

    Harry V. Wang

    2015-07-01

    Full Text Available Washington, DC, the capital of the U.S., is located along the Upper Tidal Potomac River, where a reliable operational model is needed for making predictions of storm surge and river-induced flooding. We set up a finite volume model using a semi-implicit, Eulerian-Lagrangian scheme on a base grid (200 m and a special feature of sub-grids (10 m, sourced with high-resolution LiDAR data and bathymetry surveys. The model domain starts at the fall line and extends 120 km downstream to Colonial Beach, VA. The model was used to simulate storm tides during the 2003 Hurricane Isabel. The water level measuring 3.1 m reached the upper tidal river in the vicinity of Washington during the peak of the storm, followed by second and third flood peaks two and four days later, resulting from river flooding coming downstream after heavy precipitation in the watershed. The modeled water level and timing were accurate in matching with the verified peak observations within 9 cm and 3 cm, and with R2 equal to 0.93 and 0.98 at the Wisconsin Avenue and Washington gauges, respectively. A simulation was also conducted for reconstructing the historical 1936 Potomac River Great Flood that inundated downtown. It was identified that the flood water, with a velocity exceeding 2.7 m/s in the downstream of Roosevelt Island, pinched through the bank northwest of East Potomac Park near DC. The modeled maximum inundation extents revealed a crescent-shaped flooding area, which was consistent with the historical surveyed flood map of the event.

  20. Characterization of HIV diversity, phylodynamics and drug resistance in Washington, DC.

    Directory of Open Access Journals (Sweden)

    Marcos Pérez-Losada

    Full Text Available Washington DC has a high burden of HIV with a 2.0% HIV prevalence. The city is a national and international hub potentially containing a broad diversity of HIV variants; yet few sequences from DC are available on GenBank to assess the evolutionary history of HIV in the US capital. Towards this general goal, here we analyze extensive sequence data and investigate HIV diversity, phylodynamics, and drug resistant mutations (DRM in DC.Molecular HIV-1 sequences were collected from participants infected through 2015 as part of the DC Cohort, a longitudinal observational study of HIV+ patients receiving care at 13 DC clinics. Sequences were paired with Cohort demographic, risk, and clinical data and analyzed using maximum likelihood, Bayesian and coalescent approaches of phylogenetic, network and population genetic inference. We analyzed 601 sequences from 223 participants for int (~864 bp and 2,810 sequences from 1,659 participants for PR/RT (~1497 bp.Ninety-nine and 94% of the int and PR/RT sequences, respectively, were identified as subtype B, with 14 non-B subtypes also detected. Phylodynamic analyses of US born infected individuals showed that HIV population size varied little over time with no significant decline in diversity. Phylogenetic analyses grouped 13.5% of the int sequences into 14 clusters of 2 or 3 sequences, and 39.0% of the PR/RT sequences into 203 clusters of 2-32 sequences. Network analyses grouped 3.6% of the int sequences into 4 clusters of 2 sequences, and 10.6% of the PR/RT sequences into 76 clusters of 2-7 sequences. All network clusters were detected in our phylogenetic analyses. Higher proportions of clustered sequences were found in zip codes where HIV prevalence is highest (r = 0.607; P<0.00001. We detected a high prevalence of DRM for both int (17.1% and PR/RT (39.1%, but only 8 int and 12 PR/RT amino acids were identified as under adaptive selection. We observed a significant (P<0.0001 association between main risk

  1. Circulating Practices: Migration and Translocal Development in Washington D.C. and Cochabamba, Bolivia

    Directory of Open Access Journals (Sweden)

    Christopher Strunk

    2013-09-01

    Full Text Available Migrant remittances are increasingly seen as a potential form of development in the global South, but the impact of international migration on sending regions is far from straightforward. In this article, I analyze migrant communities of origin in rural Bolivia as dynamic places that are constantly reproduced through connections with other places. I document the movement of migrant practices between Washington D.C. and Cochabamba and the influence of monetary and non-monetary flows on Bolivian cultural practices, politics, and development. I demonstrate how hometown associations and returning migrants have transferred organizational practices and political ideas about development from the United States to rural Bolivia. In addition, I explore migration’s role in struggles over belonging in Cochabamba, focusing on the efforts by migrants in Washington D.C. to stake their claim through transnational houses and collective remittance projects and on recent internal migration from other regions in Bolivia. Finally, I assess the sustainability of migrant-led development in Cochabamba. Although collaboration with migrants can strengthen the local state by providing more resources, it conditions the type of development that can take place and has yet to provide adequate opportunities for returning migrants or young people in rural Bolivia.

  2. Comparing Cost-Effectiveness of HIV Testing Strategies: Targeted and Routine Testing in Washington, DC.

    Directory of Open Access Journals (Sweden)

    Amanda D Castel

    Full Text Available Routine HIV testing is an essential approach to identifying undiagnosed infections, linking people to care and treatment, and preventing new infections. In Washington, DC, where HIV prevalence is 2.4%, a combination of routine and targeted testing approaches has been implemented since 2006.We sought to evaluate the cost effectiveness of the District of Columbia (DC Department of Health's routine and targeted HIV testing implementation strategies. We collected HIV testing data from 3 types of DC Department of Health-funded testing sites (clinics, hospitals, and community-based organizations; collected testing and labor costs; and calculated effectiveness measures including cost per new diagnosis and cost per averted transmission.Compared to routine testing, targeted testing resulted in higher positivity rates (1.33% vs. 0.44%. Routine testing averted 34.30 transmissions per year compared to targeted testing at 17.78. The cost per new diagnosis was lower for targeted testing ($2,467 vs. $7,753 per new diagnosis as was the cost per transmission averted ($33,160 vs. $104,205. When stratified by testing site, both testing approaches were most cost effective in averting new transmissions when conducted by community based organizations ($25,037 routine; $33,123 targeted compared to hospitals or clinics.While routine testing identified more newly diagnosed infections and averted more infections than targeted testing, targeted testing is more cost effective per diagnosis and per transmission averted overall. Given the high HIV prevalence in DC, the DC Department of Health's implementation strategy should continue to encourage routine testing implementation with emphasis on a combined testing strategy among community-based organizations.

  3. Longer-term effects of Washington, DC, law on drivers' hand-held cell phone use.

    Science.gov (United States)

    McCartt, Anne T; Hellinga, Laurie A

    2007-06-01

    To determine whether the substantial short-term declines in drivers' use of hand-held phones achieved in the District of Columbia (DC) were sustained 1 year after a ban. Drivers' daytime hand-held cell phone use was observed in DC and nearby areas of Virginia and Maryland, states without bans. Observations were conducted several months before the ban, shortly after, and 1 year later. The number of vehicles observed in all three surveys combined was 51,945 in DC, 36,796 in Maryland, and 43,033 in Virginia. The rate of talking on hand-held phones declined significantly from 6.1 percent before the law to 3.5 percent shortly after; when measured 1 year later, use was 4.0 percent, still significantly lower than baseline. Based on increases in rates of talking on hand-held phones in Maryland and Virginia, longer-term phone use in DC was estimated to be 53 percent lower than would have been expected without the ban. Declines in DC were identified for drivers of vehicles registered in all three jurisdictions. In DC, there was an initial decline of about 50 percent in drivers talking on hand-held cell phones following a ban, and this decline was sustained about 1 year later. After a similar ban in New York, there was an initial decline in phone use comparable with the initial decline in DC, but the decline a year after the New York ban took full effect was only about 21 percent and not statistically significant. The potential difference in sustained effectiveness for the DC ban may reflect tougher enforcement in DC. Even if full compliance with hand-held phone bans can be achieved, the risks from drivers' use of hands-free phones will remain.

  4. 108th Convention of the American Psychological Association. Washington, DC, August 4-8, 2000

    Science.gov (United States)

    2000-04-01

    Washington, DC--the nation's capital--celebrates a history rich in diversity and character. One of the most popular cities for sightseeing, Washington contains countless points of interest for its visitors. The world's largest museum complex, the Smithsonian Institution, invites you to explore exhibits that highlight the scientific, cultural, political, and technological developments of the United States and its people. Visit the home to original pieces of the American heritage, such as the Declaration of Independence, the Constitution, and the Bill of Rights, that have helped to shape the way we live today. The art lovers among you will delight in the seven major art galleries. See the modern art and sculpture of the Hirshhorn Museum and the newly opened Sculpture Garden; the Sackler Gallery's collection of Asian art; and the only museum devoted to the art and culture of Africa, the National Museum of African Art. In Washington, there is music in the air, from the Kennedy Center's many stages and the clubs of Georgetown and Adams Morgan to the military bands that give concerts on the Mall. Whatever your culinary desire, be it authentic Texas chili or the finest Asian cuisine, you'll find it at one of the city's internationally famous eateries. What a perfect place for APA to convene its first annual convention of the new millennium!

  5. Amplification of Earthquake Ground Motions in Washington, DC, and Implications for Hazard Assessments in Central and Eastern North America

    Science.gov (United States)

    Pratt, Thomas L.; Horton, J. Wright; Muñoz, Jessica; Hough, Susan E.; Chapman, Martin C.; Olgun, C. Guney

    2017-12-01

    The extent of damage in Washington, DC, from the 2011 Mw 5.8 Mineral, VA, earthquake was surprising for an epicenter 130 km away; U.S. Geological Survey "Did-You-Feel-It" reports suggest that Atlantic Coastal Plain and other unconsolidated sediments amplified ground motions in the city. We measure this amplification relative to bedrock sites using earthquake signals recorded on a temporary seismometer array. The spectral ratios show strong amplification in the 0.7 to 4 Hz frequency range for sites on sediments. This range overlaps with resonant frequencies of buildings in the city as inferred from their heights, suggesting amplification at frequencies to which many buildings are vulnerable to damage. Our results emphasize that local amplification can raise moderate ground motions to damaging levels in stable continental regions, where low attenuation extends shaking levels over wide areas and unconsolidated deposits on crystalline metamorphic or igneous bedrock can result in strong contrasts in near-surface material properties.

  6. Demonstration of LED Retrofit Lamps at the Smithsonian American Art Museum, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Naomi J.; Rosenfeld, Scott M.

    2012-06-22

    This report documents observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy GATEWAY Solid-State Lighting (SSL) Technology Demonstration Program at the Smithsonain American Art Museum in Washington, DC. LED Lamp samples were tested in the museum workshop, temporarily installed in a gallery for feedback, and ultimately replaced all traditional incandescent lamps in one gallery of modernist art at the American Art Museum and partially replacing lamps in two galleries at the Musesum's Renwick Gallery. This report describes the selection and testing process, technology challenges, perceptions, economics, energy use, and mixed results of usign LED replacement lamps in art galleries housing national treasures.

  7. Flavonoids and heart health: Proceedings of the ILSI North America Flavonoids Workshop may 31-june 1, 2005, Washington DC

    NARCIS (Netherlands)

    Erdman, J.W.; Balentine, D.; Arab, L.; Beecher, G.; Dwyer, J.T.; Folts, J.; Harnly, J.; Hollman, P.C.H.; Keen, C.L.; Mazza, G.; Messina, M.; Scalbert, A.; Vita, J.; Williamson, G.; Burrows, J.

    2007-01-01

    This article provides an overview of current research on flavonoids as presented during a workshop entitled, "Flavonoids and Heart Health," held by the ILSI North America Project Committee on Flavonoids in Washington, DC, May 31 and June 1, 2005. Because a thorough knowledge and understanding about

  8. GPS-ABC radiated chamber testing overview and results : GPS-ABC Workshop VI : RTCA Washington, DC, March 30, 2017.

    Science.gov (United States)

    2017-03-30

    This presentation, which was given during the GPS-ABC Workshop VI in Washington, DC on March 30, 2017 details the authors' radiated testing protocols and results. GPS receiver testing was carried out April 25-29, 2016 at the Army : Research Laborator...

  9. THE ROLE OF REMOTE SENSING IN IDENTIFYING BURIED WORLD WAR I MUNITIONS AT THE AMERICAN UNIVERSITY, WASHINGTON, D.C.

    Science.gov (United States)

    During World War 1, The American University in Washington D.C. was used by the U.S. Army as an experiment station for the development and testing of a variety of battlefield munitions including chemical weapons such as Mustard Gas, Phosgene, Ricin and Lewisite, among others. Afte...

  10. THE ROLE OF REMOTE SENSING IN IDENTIFYING BURIED WORLD WAR 1 MUNITIONS AT THE AMERICAN UNIVERSITY, WASHINGTON, D.C.

    Science.gov (United States)

    During World War 1, The American University in Washington D.C. was used by the U.S. Army as an experiment station for the development and testing of a variety of battlefield munitions including chemical weapons such as Mustard Gas, Phosgene, Ricin and Lewisite, among others. Afte...

  11. THE ROLE OF REMOTE SENSING AND GIS IN IDENTIFYING BURIED WORLD WAR I MUNITIONS AT THE AMERICAN UNIVERSITY, WASHINGTON, DC

    Science.gov (United States)

    During World War 1, The American University in Washington D.C. was used by the U.S. Army as an experiment station for the development and testing of a variety of battlefield munitions including chemical weapons such as Mustard Gas, Phosgene, Ricin and Lewisite, among others. Afte...

  12. Children's Health in Washington, D.C.: Access and Health Challenges despite High Insurance Coverage Rates. Research Highlights

    Science.gov (United States)

    Adamson, David M.

    2009-01-01

    In Washington, D.C., the vast majority of children have health insurance. Yet District children often lack sufficient access to medical care and face significant health threats from chronic conditions and risk factors such as exposure to violence in schools and neighborhoods. These findings emerged from an assessment of children's health in…

  13. 76 FR 26336 - Notice of Final Federal Agency Actions on the Proposed Klingle Valley Trail in Washington, DC

    Science.gov (United States)

    2011-05-06

    .../Urban Engineer, 1990 K Street, NW., Suite 510, Washington, DC 20006-1103, (202) 219-3536; or District...(c)]; 6. Social and Economic: Civil Rights Act of 1964 [42 U.S.C. 2000(d)-2000(d)(1)]; 7. Wetlands and Water Resources: Clean Water Act, 33 U.S.C. 1251- 1377 (Section 404, Section 401, Section 319); 8...

  14. Population structure of the bacterial pathogen Xylella fastidiosa among street trees in Washington D.C.

    Directory of Open Access Journals (Sweden)

    Jordan Lee Harris

    Full Text Available Bacterial leaf scorch, associated with the bacterial pathogen Xylella fastidiosa, is a widely established and problematic disease of landscape ornamentals in Washington D.C. A multi-locus sequence typing analysis was performed using 10 housekeeping loci for X. fastidiosa strains in order to better understand the epidemiology of leaf scorch disease in this municipal environment. Samples were collected from 7 different tree species located throughout the District of Columbia, consisting of 101 samples of symptomatic and asymptomatic foliage from 84 different trees. Five strains of the bacteria were identified. Consistent with prior data, these strains were host specific, with only one strain associated with members of the red oak family, one strain associated with American elm, one strain associated with American sycamore, and two strains associated with mulberry. Strains found for asymptomatic foliage were the same as strains from the symptomatic foliage on individual trees. Cross transmission of the strains was not observed at sites with multiple species of infected trees within an approx. 25 m radius of one another. X. fastidiosa strain specificity observed for each genus of tree suggests a highly specialized host-pathogen relationship.

  15. Population structure of the bacterial pathogen Xylella fastidiosa among street trees in Washington D.C.

    Science.gov (United States)

    Harris, Jordan Lee; Balci, Yilmaz

    2015-01-01

    Bacterial leaf scorch, associated with the bacterial pathogen Xylella fastidiosa, is a widely established and problematic disease of landscape ornamentals in Washington D.C. A multi-locus sequence typing analysis was performed using 10 housekeeping loci for X. fastidiosa strains in order to better understand the epidemiology of leaf scorch disease in this municipal environment. Samples were collected from 7 different tree species located throughout the District of Columbia, consisting of 101 samples of symptomatic and asymptomatic foliage from 84 different trees. Five strains of the bacteria were identified. Consistent with prior data, these strains were host specific, with only one strain associated with members of the red oak family, one strain associated with American elm, one strain associated with American sycamore, and two strains associated with mulberry. Strains found for asymptomatic foliage were the same as strains from the symptomatic foliage on individual trees. Cross transmission of the strains was not observed at sites with multiple species of infected trees within an approx. 25 m radius of one another. X. fastidiosa strain specificity observed for each genus of tree suggests a highly specialized host-pathogen relationship.

  16. Isolation of antimicrobial-resistant Escherichia coli from retail meats purchased in Greater Washington, DC, USA.

    Science.gov (United States)

    Schroeder, Carl M; White, David G; Ge, Beilei; Zhang, Yifan; McDermott, Patrick F; Ayers, Sherry; Zhao, Shaohua; Meng, Jianghong

    2003-08-15

    Four hundred and seventy-two generic Escherichia coli isolates were recovered from ground and whole retail beef, chicken, pork, and turkey obtained from Greater Washington, DC, USA during the years 1998 to 2000. Many of the isolates displayed resistance to tetracycline (59%), sulfamethoxazole (45%), streptomycin (44%), cephalothin (38%) and ampicillin (35%). Resistance was also observed, but to a lesser extent, to gentamicin (12%), nalidixic acid (8%), chloramphenicol (6%), ceftiofur (4%) and ceftriaxone (1%). Sixteen percent of the isolates displayed resistance to one antimicrobial, followed by 23% to two, 23% to three, 12% to four, 7% to five, 3% to six, 2% to seven and 2% to eight. Three E. coli isolates were shown to possess Shiga toxin genes (stx2) via PCR; all were O non-typeable and were recovered from ground beef samples purchased on the same day at the same supermarket. One of the Shiga toxin-producing E. coli (STEC) isolates was susceptible to each of the antimicrobials tested, whereas one displayed resistance to cephalothin and sulfamethoxazole, and one displayed resistance to ampicillin, cephalothin, gentamicin, streptomycin, sulfamethoxazole and tetracycline. Findings from this study indicate that retail raw meats may often be contaminated with antimicrobial-resistant E. coli.

  17. Cuando los hijos se quedan en El Salvador: Familias transnacionales y reunificación familiar de inmigrantes salvadoreños en Washington, D.C.

    Directory of Open Access Journals (Sweden)

    Sánchez Molina, Raúl

    2004-12-01

    Full Text Available Current migratory flows develope new social-cultural patterns such as transnational families. Using ethnographic data collected in Washington, D.C. and El Salvador, this article describes and analyzes the different strategies develop by Salvadoran immigrants living in the Washington, D.C. metropolitan area to re-shape their domestic units. The immigrant modes of incorporation into the US societies and the logic of family unity affect these configurations to such an extent that until all the family members can be together again, the pre-migratory cultural patterns and those acquired in the host society affect in the transnational family configurations.

    Los actuales movimientos migratorios están propiciando el desarrollo de patrones socioculturales transnacionales que, en el ámbito de las unidades domésticas, permiten configuraciones de familias transnacionales. A partir de los datos obtenidos en una investigación etnográfica transnacional, este artículo describe y analiza las estrategias de inmigrantes en la reestructuración de sus familias. La lógica de la unidad familiar, por un lado, y los modos de incorporación de los salvadoreños al área metropolitana de Washington, D.C., por otro, explican las estrategias utilizadas por los inmigrantes en las reestructuración de sus unidades domésticas. De tal manera que hasta que los miembros de la familia puedan estar juntos de nuevo, tanto los patrones culturales premigratorios, como los adquiridos en las sociedades de asentamiento influyen en las configuraciones de las familias transnacionales.

  18. SALMO-PRIEST WILDERNESS STUDY AREA, WASHINGTON AND IDAHO.

    Science.gov (United States)

    Miller, F.K.; Schmauch, S.W.

    1984-01-01

    Geologic, geochemical, geophysical and mines and prospects evaluation of the Salmo-Priest Wilderness study area in Washington has yielded no evidence of significant mineral-resource potential. Although gold was detected in trace amounts to moderate anomalies in scattered stream-sediment concentrates it has probably been derived from small and localized occurrences and does not constitute a resource. As a result of this study the area appears to have little promise for the occurrence of metallic mineral resources, energy minerals, fossil fuels, and geothermal resources. Nonmetallic mineral resources, notably shale, are abundant, but adequate supplies exist outside the study area.

  19. Patterns of alcohol consumption among pregnant African-American women in Washington, DC, USA.

    Science.gov (United States)

    Kiely, Michele; Thornberry, Jutta S; Bhaskar, Brinda; Rodan, Margaret F

    2011-07-01

    The objective of this paper is to describe the patterns and associated behaviours related to alcohol consumption among a selected sample of pregnant women seeking prenatal care in inner city Washington DC. Women receiving prenatal care at one of nine sites completed an anonymous alcohol-screening questionnaire. Questions concerned the amount, type and pattern of alcohol consumption. Women were categorised as at no, low, moderate or high risk for alcohol consumption during pregnancy. For comparisons of risk levels of drinking, bivariate associations were examined using Fisher's exact test. Odds ratios (ORs) and 95% confidence intervals (CIs) were also computed. Although 31% of current/recent drinkers stated that they continued to drink during pregnancy, responses to quantity/frequency questions revealed that 42% continued to do so. Women who were at high compared with moderate risk acknowledged that others were worried about their consumption [OR=4.0, 95% CI 1.5, 10.6], that they drank upon rising [OR=6.7, 95% CI 1.8, 26.9], had a need to reduce drinking [OR=3.2, 95% CI 1.3, 8.1] and in the past 5 years had had fractures [OR=4.2, 95% CI 1.0, 17.8] or a road traffic injury [OR=3.4, 95% CI 1.0, 12.2]. Women in the high/moderate compared with low-risk group were more likely to have been injured in a fight or assault [OR=2.7, 95% CI 1.3, 5.6]. This study validated the usefulness of our questionnaire in identifying women who were at risk for alcohol consumption during pregnancy across a range of consumption levels. Using our screening tool, women were willing to disclose their drinking habits. This low-cost method identifies women appropriate for targeting of interventions. © 2011 Blackwell Publishing Ltd.

  20. Distress of Routine Activities and Perceived Safety Associated with Post-Traumatic Stress, Depression, and Alcohol Use: 2002 Washington, DC, Sniper Attacks.

    Science.gov (United States)

    Fullerton, Carol S; Herberman Mash, Holly B; Benevides, K Nikki; Morganstein, Joshua C; Ursano, Robert J

    2015-10-01

    For over 3 weeks in October 2002, a series of sniper attacks in the Washington, DC, area left 10 people dead and 3 wounded. This study examined the relationship of distress associated with routine activities and perceived safety to psychological and behavioral responses. Participants were 1238 residents of the Washington, DC, metropolitan area (aged 18 to 90 years, mean=41.7 years) who completed an Internet survey including the Impact of Event Scale-Revised, Patient Health Questionnaire-9, and items pertaining to distress related to routine activities, perceived safety, and alcohol use. Data were collected at one time point approximately 3 weeks after the first sniper shooting and before apprehension of the suspects. Relationships of distress and perceived safety to post-traumatic stress, depressive symptoms, and increased alcohol use were examined by using linear and logistic regression analyses. Approximately 8% of the participants met the symptom criteria for probable post-traumatic stress disorder, 22% reported mild to severe depression, and 4% reported increased alcohol use during the attacks. Distress related to routine activities and perceived safety were associated with increased post-traumatic stress and depressive symptoms and alcohol use. Distress and perceived safety are associated with specific routine activities and both contribute to psychological and behavioral responses during a terrorist attack. These findings have implications for targeted information dissemination and risk communication by community leaders.

  1. Influence of Land Use, Discharge and Impervious Surfaces on the Geochemistry of the Anacostia River, Washington DC.

    Science.gov (United States)

    MacAvoy, S. E.; De Filippis, N.

    2016-12-01

    Challenges facing urban rivers include water stormwater runoff and changing water chemistry, not only from air and water pollution, but also from altered geology with the development of "urban karst" (concrete). The Anacostia River in Washington, D.C. has 75% of its watershed classified as urban or impervious, and is among the 10 most contaminated rivers in the USA. In addition to its relatively well-documented organic contamination problems, we hypothesize that concrete could be substantially altering its geochemistry. Here we report findings from 6 locations along the Anacostia River and its tributaries that indicate both seasonally elevated Na and Cl (becoming brackish, 2000-3000 mg/L Total Dissolved Solids, in a suburban creek), and elevated cations in low flow suburban tributaries. Concentrations of all major cations (Ca, Mg, K, Na) strongly, and positively, covaried (factor scores (FC) >0.88). However Ca/Sr ratios negatively covaried with major cations (FC -0.64). This suggests the weathering of low Sr minerals, such as those in concrete. In urbanized portions of the river, Ca/Sr was >200, which is a concrete weathering indicator in areas with silica mineral bedrock (Anacostia bedrock consists of Precambrian phyllits, sericite, chlorite, quartzite, slate and schist). Mean ± SE Sr was 0.13 ± 0.02 mg/L in the most urban area, but 0.37 ± 0.03 mg/L in the most suburban. This supports the hypothesis that the source of elevated cations in the urban areas is concrete weathering, not bedrock mineral weathering. Inorganic N was not correlated strongly with cations. Mean NO3- was highest at the most suburban site (1.8 ± 0.2 mg/L), but rose above 3 mg/L in some samples at all sites. Elevated NO3- did not appear to vary with season or discharge rate at time of sampling. NH4+ was generally lower than 1 mg/L but spiked to 3.4 mg/L at the most urban site. These data follow patterns expected for "urban stream syndrome". Suburban areas, with their relatively small streams

  2. Examining relationships between perceptions and objective assessments of neighborhood environment and sedentary time: Data from the Washington, D.C. Cardiovascular Health and Needs Assessment

    Directory of Open Access Journals (Sweden)

    Chaarushi Ahuja

    2018-03-01

    Full Text Available Sedentary time (ST and neighborhood environment (NE are predictors of cardiovascular (CV health. However, little is known about ST's relationship with NE. We examined associations of perceived and objective NE with ST in the predominantly African American faith-based population of the Washington, D.C. CV Health and Needs Assessment. After using community-based research principles, participants reported NE perceptions, including sidewalks, recreational areas, and crime presence. Factor analysis was conducted to explore pertinent constructs; factor sums were created and combined as Total Perception Score (TPS (higher score = more favorable perception. Objective NE was assessed using Google Maps and the Active Neighborhood Checklist (ANC. ST was self-reported. Linear regression determined relationships between TPS and ST, and ANC scores and ST, for 1 overall population, 2 lower median-income D.C. areas, and 3 higher median-income DC and Maryland areas. For the sample (N = 98.9% African-American, 78% female, lower median-income areas had significantly lower mean TPS and ANC scores than higher median-income areas (p < 0.001. Three factors (neighborhood violence, physical/social environment, and social cohesion were associated with overall NE perception. Among those in lower median-income areas, there was a negative association between TPS and ST that remained after covariate adjustment; this was not observed in higher median-income areas. There was no association between ANC scores and ST. Poorer NE perception is associated with greater ST for those in lower income areas, while objective environment is not related to ST. Multi-level interventions are needed to improve NE perceptions in lower-median income areas, reduce ST, and improve CV health.

  3. Psychological resilience: the impact of affectivity and coping on state anxiety and positive emotions during and after the Washington, DC sniper killings.

    Science.gov (United States)

    Moore, Philip J; Chrabaszcz, Jeffrey S; Peterson, Rolf A; Rohrbeck, Cynthia A; Roemer, Enid C; Mercurio, Andrea E

    2014-01-01

    This research examined the impact of affectivity and coping on state anxiety and positive emotions among young adults living in the Washington, DC metro area both during and after the Washington, DC sniper killings. Participants completed questionnaires during three waves of data collection: (1) during the sniper attacks (n=92); (2) within two weeks after the snipers were captured (n=45); and (3) six months later (n=43). Affectivity (measured by neuroticism) was significantly associated with state anxiety and positive emotions during all three time periods. Coping (measured by constructive thinking) predicted state anxiety and positive emotions during the shootings, but was unrelated to either outcome immediately after the attacks, and marginally related to them six months later. Consistent with the Dynamic Model of Affect, state anxiety and positive emotions were more strongly (and negatively) correlated with each other during the killings than they were after the snipers were apprehended. Taken together, these results support transactional models of stress that emphasize the interaction between dispositional and situational influences, and they suggest that affectivity reflects a fundamental set of reactions to one's environment, while coping dispositions result in more stress-specific responses. Additional theoretical and practical implications of these findings are also discussed.

  4. Integrating Infrastructure-Relevant Climate Projections into City Planning: Learning from Boulder CO, Austin TX and Washington DC

    Science.gov (United States)

    Stoner, A. M. K.; Hayhoe, K.

    2015-12-01

    Over the coming century, climate change has the potential to impact infrastructure in many different ways, particularly in population-dense areas that depend on transportation and built environments. Many of these impacts may occur via changes in the frequency and magnitude of extremes: high and low temperature, heat waves, precipitation, coastal flooding, and storm events. Having a better idea of how the climate might change locally, both within the near future as well as toward the end of the century, can give city planners and engineers guidance when designing new structures and when repairing and fortifying existing components of buildings, bridges, highways, sewers, ports, etc. However, the type of event and the amount of damages that may be incurred are often highly specific to a given location. Over the last 10 years, we have worked with a broad range of cities, states, non-profit organizations, and federal agencies to integrate climate projections into ongoing resiliency, sustainability, and management processes. Drawing on that experience, we describe the broad steps in assimilating climate information into existing decision-making frameworks relevant to most applications, as well as highlighting many of the unique aspects of these analyses using examples from our most recent work with three very different cities - Austin TX, Boulder CO and Washington DC. From initial conversations with local experts to identify relevant thresholds to final integration of projected changes into the planning processes of these cities, these case studies highlight the utility of including future climate projections into infrastructure planning, the challenges to doing so, and the over-arching importance of communication and interaction between infrastructure experts, engineers, and scientists.

  5. Quantifying Fluxes of Greenhouse Gases in Baltimore-Washington Metropolitan Area from Airborne Measurements

    Science.gov (United States)

    Ahn, D.; Hansford, J. R.; Salawitch, R. J.; Ren, X.; Dickerson, R. R.

    2016-12-01

    We quantify fluxes of CO2, CH4 and CO from various emission sources in the Baltimore-Washington metropolitan area using airborne in-situ measurements, obtained during the February 2015 Fluxes of Greenhouse Gases in Maryland (FLAGG-MD) campaign. In this study, we focus on the attribution of enhanced signals of CO2, CH4, and CO to various emission sources in the region, including point (power plants, landfill, coal mines), area (Baltimore city, Washington DC), and mobile sources by making use of the NOAA HYSPLIT air parcel trajectory model as well as the analysis of chemical ratios. The Brown Station landfill in Maryland was found to be a major source of methane. The flux of each attributed compound is then estimated using a mass balance approach, and results are compared to various sources of emission data, such as CEMS, CarbonTracker, FFDAS, and ODIAC. Finally, the uncertainty of aircraft-based mass balance approach is quantified by conducting a sensitivity analysis of calculated flux to such factors as PBL height, wind direction and speed, interpolation methods, and background concentration.

  6. Large Dog Relinquishment to Two Municipal Facilities in New York City and Washington, D.C.: Identifying Targets for Intervention

    Science.gov (United States)

    Weiss, Emily; Slater, Margaret; Garrison, Laurie; Drain, Natasha; Dolan, Emily; Scarlett, Janet M.; Zawistowski, Stephen L.

    2014-01-01

    Simple Summary While the overall trend in euthanasia has been decreasing nationally, large dogs are at a higher risk of euthanasia than other-sized dogs in most animal shelters in the United States. We hypothesized that one way to increase the lives saved with regard to large dogs in shelters is to keep them home in the first place when possible. Our research is the first to collect data in New York City and Washington, D.C., identifying the process leading to the owner relinquishment of large dogs. We found that targets for interventions to decrease large dog relinquishment are likely different in each community. Abstract While the overall trend in euthanasia has been decreasing nationally, large dogs are at a higher risk of euthanasia than other sized dogs in most animal shelters in the United States. We hypothesized one way to increase the lives saved with respect to these large dogs is to keep them home when possible. In order to develop solutions to decrease relinquishment, a survey was developed to learn more about the reasons owners relinquish large dogs. The survey was administered to owners relinquishing their dogs at two large municipal facilities, one in New York City and one in Washington, D.C. There were 157 responses between the two facilities. We found both significant similarities and differences between respondents and their dogs from the two cities. We identified opportunities to potentially support future relinquishers and found that targets for interventions are likely different in each community. PMID:26480315

  7. Expanding hospital HIV testing in the Bronx, New York and Washington, D.C.: Results from the HPTN 065 study.

    Science.gov (United States)

    Branson, Bernard M; Chavez, Pollyanna R; Hanscom, Brett; Greene, Elizabeth; McKinstry, Laura; Buchacz, Kate; Beauchamp, Geetha; Gamble, Theresa; Zingman, Barry S; Telzak, Edward; Naab, Tammey; Fitzpatrick, Lisa; El-Sadr, Wafaa M

    2017-11-27

    HIV testing is critical for both HIV treatment and prevention. Expanding testing in hospital settings can identify undiagnosed HIV infections. To evaluate the feasibility of universally offering HIV testing during emergency department (ED) visits and inpatient admissions, 9 hospitals in the Bronx, New York and 7 in Washington DC undertook various efforts to encourage staff to offer HIV testing routinely. Outcomes included the percentage of encounters with an HIV test, the change from year 1 to year 3, and the percentages of tests that were HIV-positive and new diagnoses. From February 1, 2011 to January 31, 2014, HIV tests were conducted during 6.5% of 1,621,016 ED visits and 13.0% of 361,745 inpatient admissions in Bronx hospitals and 13.8% of 729,172 ED visits and 22.0% of 150,655 inpatient admissions in DC, with wide variation by hospital. From year 1 to year 3, testing was stable in the Bronx (6.6% to 6.9% of ED visits, 13.0% to 13.6% of inpatient admissions), but increased in DC (11.9% to 15.8% of ED visits, 19.0% to 23.9% of inpatient admissions). Overall, in the Bronx 0.4% (408) of ED HIV tests were positive, 0.3% (277) were new diagnoses; 1.8% (828) of inpatient tests were positive, 0.5% (244) were new diagnoses. In DC, 0.6% (618) of ED tests were positive, 0.4% (404) were new diagnoses; 4.9% (1349) of inpatient HIV tests were positive, 0.7% (189) were new diagnoses. Hospitals consistently identified previously undiagnosed HIV infections, but universal offer of HIV testing proved elusive.

  8. Large Dog Relinquishment to Two Municipal Facilities in New York City and Washington, D.C.: Identifying Targets for Intervention

    Directory of Open Access Journals (Sweden)

    Emily Weiss

    2014-07-01

    Full Text Available While the overall trend in euthanasia has been decreasing nationally, large dogs are at a higher risk of euthanasia than other sized dogs in most animal shelters in the United States. We hypothesized one way to increase the lives saved with respect to these large dogs is to keep them home when possible. In order to develop solutions to decrease relinquishment, a survey was developed to learn more about the reasons owners relinquish large dogs. The survey was administered to owners relinquishing their dogs at two large municipal facilities, one in New York City and one in Washington, D.C. There were 157 responses between the two facilities. We found both significant similarities and differences between respondents and their dogs from the two cities. We identified opportunities to potentially support future relinquishers and found that targets for interventions are likely different in each community.

  9. Modeling air pollution in the Washington, D.C., to Boston megalopolis.

    Science.gov (United States)

    Slade, D H

    1967-09-15

    Simplified meteorological models and pollutant source configurations were used to demonstrate the types of pollutant patterns that might be encountered in the Washington, D.C.-Boston megalopolitan corridor. A semirealistic source distribution and source intensity of carbon dioxide were used in this demonstration. The results of the computations suggest that local increases in quantities of pollutants may at times require regional rather than local source consideration.

  10. 2013 EFRC PI Meeting -- Science for Our Nation's Energy Future: Energy Frontier Research Centers Principal Investigators' Meeting, Washington, D.C., July 18-19, 2013

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2013-07-01

    2013 EFRC Principal Investigators’ Meeting, July 18-19, 2013 in Washington D.C. By invitation only--about 500 attendees from the EFRCs and DOE, 235 senior EFRC members and 165 EFRC early career scientists from more than 80 institutions in 31 states, 2 foreign countries and Washington D.C. Over 115 talks and 225 posters

  11. Childhood sexual abuse and HIV-related risks among men who have sex with men in Washington, DC.

    Science.gov (United States)

    Phillips, Gregory; Magnus, Manya; Kuo, Irene; Rawls, Anthony; Peterson, James; Montanez, Luz; West-Ojo, Tiffany; Jia, Yujiang; Opoku, Jenevieve; Greenberg, Alan E

    2014-05-01

    Childhood sexual abuse (CSA) has been reported to be disproportionately higher among men who have sex with men (MSM) than among heterosexual men; it has also been found to be significantly positively associated with HIV status and HIV risk factors, including unprotected anal intercourse. The purpose of this study was to assess the correlates of CSA in a sample of community-recruited MSM, investigate race as a potential effect modifier, and describe the independent association between CSA and HIV infection in Washington, DC. A total of 500 MSM were recruited by venue-based sampling in 2008 as part of the National HIV Behavioral Surveillance. More than one-half of MSM identified as White, while one-third identified as Black. CSA was reported by 17.5 % of the 451 MSM, with the first instance of abuse occurring at a median age of 8.3 (interquartile range = 5.0, 11.0). In multivariable analysis, HIV-positive men were significantly more likely to report a history of CSA compared to HIV-negative men after adjusting for intimate partner violence in the last 12 months, having been arrested in the last 12 months, and depressive symptoms. HIV-positive MSM had more than four times the odds of reporting CSA after controlling for other correlates (aOR = 4.19; 95 % CI 2.26, 7.75). Despite hypothesizing that race modified the effect of CSA on HIV infection we found this was not the case in this sample. More research is needed to investigate the potential pathway between a history of CSA and HIV infection, and how this contributes to driving the HIV epidemic among MSM in Washington, DC.

  12. Geology and ground-water resources of Washington, D.C., and vicinity

    Science.gov (United States)

    Johnston, Paul McKelvey

    1964-01-01

    constructed. Bored or dug wells allow greater storage capacity and are satisfactory for domestic supplies in some locations, but they are polluted easily. If not properly constructed or of sufficient depth, they may fail in dry weather. Ground-water supplies for domestic use, 5 to 10 gpm (gallons per minute), are obtainable in most places. In the Piedmont, recorded yields in drilled wells range from 0.2 to 212 gpm. In the Coastal Plain, wells yield from 1 to 800 gpm. The quality of the ground water in the report area is generally satisfactory for domestic, industrial, and irrigation use. High iron content and corrosiveness are troublesome in places. The water is soft to moderately hard--2 to 175 ppm (parts per million). Water in the Piedmont province is. dominantly the calcium and bicarbonate type; in the Coastal Plain most water is of calcium-magnesium bicarbonate type. In the Piedmont, careful location of wells with respect to the geology (rock type and structure) and to topography usually results in higher yields and may mean the difference between success and failure. In the Coastal Plain, drilled artesian wells are not affected by topography, but the yield obtained depends upon the penetration of a water-bearing sand or gravel bed at sufficient depth. The early settlers obtained water from the springs and streams, and later from dug wells. After Washington was established as the Capital in 1800, water was obtained from public and privately owned wells. Water was piped from some of the springs to government buildings and to private homes and business houses. In 1863 a diversion dam was completed in the Potomac above Great Falls and a conduit was built into the city to furnish a public water supply. This system with modifications has been in use ever since. A new diversion dam and pumping station at Little Falls was put into service in the summer of 1959. In 1961 the total pumpage from Coastal Plain aquifers in the report area was estimate

  13. THE ROLE OF THE REMOTE SENSING IN IDENTIFYING BURIED WORLD WAR I MUNITIONS AT THE AMERICAN UNIVERSITY, WASHINGTON, D.C.

    Science.gov (United States)

    During World War 1, The American University in Washington D.C. was used by the U.S. Army as an experiment station for the development and testing of a variety of battlefield munitions including chemical weapons such as Mustard Gas, Phosgene, Ricin and Lewisite, among othe...

  14. THER ROLE OF REMOTE SENSING AND GIS IN IDENTIFYING AND REMOVING BURIED WORLD WAR I MUNITIONS AT THE AMERICAN UNIVERSITY, WASHINGTON, DC

    Science.gov (United States)

    During World War I, The American University in Washington D.C. was used by the U.S. Am1y as an experiment station for the development and testing of a variety of battlefield munitions including chemical weapons such as Mustard Gas, Phosgene, Ricin and Lewisite, among others. Afte...

  15. Annual Disruptive Technologies Conference (8th) Held in Washington, DC on November 8-9, 2011

    Science.gov (United States)

    2011-11-09

    Chandrasekhar, V. Dravid, R. Letsinger, G. Schatz, S. Stupp, D. Ginger • Harold Washington – T. Higgins • Tufts – D. Kaplan • Scripps – M. Ghadiri...density act as acceptors or donors N-doped P-doped Inducing Circulation with OAM Beams LG01 ‘Ring’ beam ‘Sheet’ beam ~40 µm T < 40nK “SQUIDs...squeeze device prick finger blood blood on filter plasma (with liver function tests) Soft Robotics D P = 0 D P = + k2 k1

  16. Area of old-growth forests in California, Oregon, and Washington.

    Science.gov (United States)

    Charles L. Bolsinger; Karen L. Waddell

    1993-01-01

    Area of old-growth forests in California, Oregon, and Washington has declined significantly in the second half of the 20th century. This report summarizes available information on old-growth forest area by ownership in California, Oregon, and Washington. Old-growth definitions used by the various owners and agencies are provided.

  17. Area of old-growth forests in California, Oregon, and Washington. Forest Service research bulletin

    Energy Technology Data Exchange (ETDEWEB)

    Bolsinger, C.L.; Waddell, K.L.

    1993-12-01

    An area of old-growth forests in California, Oregon, and Washington has declined significantly in the second half of the 20th century. The report summarizes available information on old-growth forest area by ownership in California, Oregon, and Washington. Old-growth definitions used by the various owners and agencies are provided.

  18. A qualidade de vida de jovens portadores de espinha bífida do Children's National Medical Center – Washington DC The quality of life of adolescents with spina bifida at the Children's National Medical Center – Washington DC

    Directory of Open Access Journals (Sweden)

    Ana Helena Rotta Soares

    2006-09-01

    Full Text Available O presente artigo tem como objetivo explorar a qualidade de vida de jovens portadores de espinha bífida atendidos no Children's National Medical Center em Washington DC. A pesquisa baseia-se em uma perspectiva qualitativa que utiliza como referencial teórico central a "Teoria do estigma" e as discussões conceituais sobre as dimensões de qualidade de vida. Foram entrevistados 15 jovens do serviço acima citado, sendo que 8 deles participaram de um grupo focal construído através das questões levantadas durante entrevistas. Os discursos dos jovens em questão refletem a necessidade de categorias mais englobantes que não remetam a uma pulverização da experiência de vida. Evidenciou-se uma estrutura de desigualdade nas interações entre saudáveis e deficientes, e reproduzida pelos próprios jovens. Os resultados demonstram que o estigma se encontra presente em todas as dimensões da vida dos sujeitos, interferindo na inserção social, construção subjetiva do jovem e sua auto-estima, reforçando o papel do portador de deficiência como uma "não-pessoa". Embora a categoria sexualidade não seja priorizada em outros instrumentos para esta população, o tema se faz presente e central na discussão da experiência da vida dos mesmos.The present article explores the quality of life of adolescents with spina bifida at the Children's National Medical Center in Washington DC. The research is based on a qualitative perspective that utilizes the "Theory of stigma" as the central theoretical framework, in addition to the discussions of the concept of quality of life and its dimensions. Fifteen adolescents were interviewed at the above institution, eight of which then participated in a focal group structured through issues that emerged during this previous phase. The discourses reflected the need for more encompassing categories for quality of life that do not pulverize the life experience. The adolescent's discourses demonstrate an inequality

  19. Examination of particulate matter and heavy metals and their effects in at-risk wards in Washington, DC

    Science.gov (United States)

    Greene, Natasha Ann

    One of the major contributions to pollution in the Washington, DC urban environment is particulate matter (PM). Quite often, ambient airborne toxics are closely associated with fine PM (PM2.5). We have performed high-resolution aerosol measurements of PM2.5 in four wards (Ward 1, 4, 5, and 7) of Washington, DC during two intensive observational periods (IOP). The first IOP occurred during the summer of 2003 (June 23rd to August 8th). The second IOP transpired during the late fall season of 2003 (October 20th to December 4 th). The measurement platform consisted of a Laser Particle Counter (LPC) and a Quartz Crystal Microbalance Cascade Impactor (QCM) to obtain both in-situ number and mass density distributions across the measurement sites. The data shows spatial distributions of particulate matter characterized as a function of size and mass properties. The QCM analyses show significant levels (> 15 mug/m3) of ward-averaged PM2.5 in Wards 4, 1, and 7 respectively during the summer IOP. However, all wards were less than the EPA National Ambient Air Quality Standard (NAAQS) of 15 mug/m 3 during the fall IOP ward-averaged measurements. Yet, investigations of the site-averaged measurements during the fall revealed some specific locations in Ward 4 that exceeded the NAAQS. Results also show that the aerosol mass density peaked in the 0.3 mum mode during the summer IOP and in the 0.15 mum mode during the fall IOP. The number density peaked in the 0.3--0.5 mum size range. Accordingly, the distributions have also been analyzed as a function of meteorological factors, such as wind speed and direction via NOAA HYSPLIT trajectories. One important attribute to this study is the evaluation of risks amongst IBC subgroups (youth, adults, elderly, black, white, hispanic, male, and female) for bath pediatric asthma rates and the onset of lung cancer over a lifetime (70-year period) when exposed to these levels of particulates. It has been determined that there are individual excess

  20. Proceedings of the American Psychological Association, Incorporated, for the legislative year 2015: Minutes of the Annual Meeting of the Council of Representatives February 20-22, 2015, Washington, DC, and August 5 and August 7, 2015, Washington, DC, and minutes of the February, June, August, and December 2015 meetings of the Board of Directors.

    Science.gov (United States)

    Kelly, Jennifer F

    2016-01-01

    This article provides the minutes of the Annual Meeting of the Council of Representatives February 20-22, 2015, Washington, DC, and August 5 and August 7, 2015, Washington, DC, and minutes of the February, June, August, and December 2015 meetings of the Board of Directors. These minutes are the official record of the actions of the Association taken during the year by both the Board of Directors (the Board) and the Council of Representatives (Council). They are arranged in topical rather than chronological order, and subheadings are used when appropriate. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  1. U.S. Department of Energy Hydrogen and Fuel Cells Program 2014 Annual Merit Review and Peer Evaluation Report: June 16-20, 2014, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    2014-10-01

    The fiscal year (FY) 2014 U.S. Department of Energy (DOE) Hydrogen and Fuel Cells Program Annual Merit Review and Peer Evaluation Meeting (AMR), in conjunction with DOE's Vehicle Technologies Office AMR, was held from June 16-20, 2014, at the Washington Marriott Wardman Park in Washington, D.C. This report is a summary of comments by AMR peer reviewers about the hydrogen and fuel cell projects funded by DOE's Office of Energy Efficiency and Renewable Energy (EERE).

  2. Solar Decathlon Visitors Guide 2011, National Mall, West Potomac Park, Washington, D.C., September 23 - October 2, 2011 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2011-09-01

    Guide to the student-designed houses, ten contests, exhibits, and workshops of the U.S. Department of Energy 2011 Solar Decathlon, held in Washington, D.C., from September 23 through October 2, 2011. Teams of college students designed and built the solar-powered houses on display here. They represent 13 U.S. states, five countries, and four continents. Now the teams are rising to the challenge by competing in 10 contests over nine days, with the championship trophy on the line. This is their time to shine. The 2011 teams may share a common goal - to design and build the best energy-efficient house powered by the sun - but their strategies are different. One house is made of precast concrete, while another 'dances' in response to its environment. Another house is meant to sit atop a building, proving the sky's the limit for energy innovation. Whatever your idea of sustainable living may be, you are bound to find it at the Solar Decathlon.

  3. Movement of a solute in the Potomac River estuary at Washington, D.C., at low inflow conditions

    Science.gov (United States)

    Wilson, James F.; Cobb, Ernest D.; Yotsukura, Nobuhiro

    1969-01-01

    The movement of a solute, as represented by a soluble fluorescent dye, was observed in the Potomac River estuary at Washington, D.C. The average net rate of downstream movement of the solute centroid was less than 0.6 mile per day. The movement of a solute is highly dependent on the nontidal inflow to the estuary. During the study, the average inflow was 900 cubic feet per second a very low value, equaled or exceeded 98 percent of the time. Using a storage equation, the average movement of a solute was estimated for nontidal inflow of 3,100 and 6,500 cubic feet per second; these inflows are equaled or exceeded 75 and 50 percent of the time, respectively. The study showed that tidal action was fairly efficient in dispersing the solute longitudinally. The solute, which was dumped 1,000 feet upstream from the 14th Street Bridge, was observed as far upstream as Roosevelt Island. A transient longitudinal dispersion coefficient at the end of 150 hours was determined to be 210 square feet per second. On the other hand, the lateral diffusion was a slow process and the lateral distribution of the solute was far from uniform at the end of 6? days after the release.

  4. Report of a workshop on nuclear forces and nonproliferation Woodrow Wilson international center for scholars, Washington, DC October 28, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Pilat, Joseph F [Los Alamos National Laboratory

    2010-12-08

    A workshop sponsored by the Los Alamos National Laboratory in cooperation with the Woodrow Wilson International Center for Scholars was held at the Wilson Center in Washington, DC, on October 28, 2010. The workshop addressed evolving nuclear forces and their impacts on nonproliferation in the context of the new strategic environment, the Obama Administration's Nuclear Posture Review and the 2010 NPT Review Conference. The discussions reflected the importance of the NPR for defining the role of US nuclear forces in dealing with 21st century threats and providing guidance for National Nuclear Security Administration (NNSA) and Department of Defense (DoD) programs and, for many but not all participants, highlighted its role in the successful outcome of the NPT RevCon. There was widespread support for the NPR and its role in developing the foundations for a sustainable nuclear-weapon program that addresses nuclear weapons, infrastructure and expertise in the broader nonproliferation, disarmament and international security contexts. However, some participants raised concerns about its implementation and its long-term effectiveness and sustainability.

  5. Expanding veterinary biosurveillance in Washington, DC: The creation and utilization of an electronic-based online veterinary surveillance system.

    Science.gov (United States)

    Hennenfent, Andrew; DelVento, Vito; Davies-Cole, John; Johnson-Clarke, Fern

    2017-03-01

    To enhance the early detection of emerging infectious diseases and bioterrorism events using companion animal-based surveillance. Washington, DC, small animal veterinary facilities (n=17) were surveyed to determine interest in conducting infectious disease surveillance. Using these results, an electronic-based online reporting system was developed and launched in August 2015 to monitor rates of canine influenza, canine leptospirosis, antibiotic resistant infections, canine parvovirus, and syndromic disease trends. Nine of the 10 facilities that responded expressed interest conducting surveillance. In September 2015, 17 canine parvovirus cases were reported. In response, a campaign encouraging regular veterinary preventative care was launched and featured on local media platforms. Additionally, during the system's first year of operation it detected 5 canine leptospirosis cases and 2 antibiotic resistant infections. No canine influenza cases were reported and syndromic surveillance compliance varied, peaking during National Special Security Events. Small animal veterinarians and the general public are interested in companion animal disease surveillance. The system described can serve as a model for establishing similar systems to monitor disease trends of public health importance in pet populations and enhance biosurveillance capabilities. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Recasting the Significant: The Transcultural Memory of Alexander von Humboldt’s Visit to Philadelphia and Washington, D.C.

    Directory of Open Access Journals (Sweden)

    James F. Howell

    2016-07-01

    Full Text Available Alexander von Humboldt was internationally known as a world traveler, having collected data and analyzed samples from five of the world’s seven continents. He spoke several languages fluently, and split most of his adult life between the cosmopolitan centers of Berlin and Paris. The great deal of time Humboldt spent in Latin America, along with his staunch belief in human equality, led to his reverence in those countries. Indeed, Humboldt was a world citizen in the truest sense of the word. But what of the United States? What claim can this nation make to the heritage and legacy of the world-exploring baron? A brief stop in Philadelphia and Washington, D.C. at the end of Humboldt’s expedition to the equatorial regions of the Americas seems to suffice. This short stay, along with the Humboldt-Jefferson correspondence, constitutes the great American link in Humboldt studies, a link whose nature and importance has, over the years, received an exaggerated amount of attention from authors writing for an American audience. The following analysis, using the tools of transcultural memory studies, investigates why this relatively insignificant event in a long and storied life assumes an inflated role in current accounts of the life and work of Alexander von Humboldt.

  7. U.S. Department of Energy Hydrogen and Fuel Cells Program 2016 Annual Merit Review and Peer Evaluation Report: June 6-10, 2016, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Popovich, Neil

    2016-10-01

    The fiscal year 2016 U.S. Department of Energy (DOE) Hydrogen and Fuel Cells Program Annual Merit Review and Peer Evaluation Meeting (AMR), in conjunction with DOE's Vehicle Technologies Office AMR, was held from June 6-10, 2015, in Washington, D.C.. This report is a summary of comments by AMR peer reviewers about the hydrogen and fuel cell projects funded by DOE's Office of Energy Efficiency and Renewable Energy.

  8. 75 FR 1406 - National Mall and Memorial Parks, Washington, DC; Notice of Availability of an Environmental...

    Science.gov (United States)

    2010-01-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR... nation, dating from 1790. The study area contains a significant concentration of our Nation's memorials...: If you wish to comment, you may submit your comments online by visiting http://www.nps.gov...

  9. Proceedings of the AMEDD Psychology Symposium Held at Washington, DC on 27-31 October 1980

    Science.gov (United States)

    1983-12-01

    Department of Neurosciences , Walter Reed Army Institute of Research. He is also a member of the faculty of the Uniformed Services University of the...Area of Specialization: Child and Family Studies 1 Health Education 1 Child and Adolescent 3 Comnunity Psychology’ 2 Neuropsychology 1 Clinical Hypnosis ... Neurosciences , WRAIR. 5. Dr. Theodore H. Blau, past president of the American Psychological Association and Consultant to the Arnm Surgeon General. 6. Dr

  10. Pesticides in groundwater in the Anacostia River and Rock Creek watersheds in Washington, D.C., 2005 and 2008

    Science.gov (United States)

    Koterba, Michael T.; Dieter, Cheryl A.; Miller, Cherie V.

    2010-01-01

    The U.S. Geological Survey (USGS), in cooperation with the District Department of the Environment, conducted a groundwater-quality investigation to (a) determine the presence, concentrations, and distribution of selected pesticides in groundwater, and (b) assess the presence of pesticides in groundwater in relation to selected landscape, hydrogeologic, and groundwater-quality characteristics in the shallow groundwater underlying the Anacostia River and Rock Creek watersheds in Washington, D.C. With one exception, well depths were 100 feet or less below land surface. The USGS obtained or compiled ancillary data and information on land use (2001), subsurface sediments, and groundwater samples from 17 wells in the lower Anacostia River watershed from September through December 2005, and from 14 wells in the lower Anacostia River and lower Rock Creek watersheds from August through September 2008. Twenty-seven pesticide compounds, reflecting at least 19 different types of pesticides, were detected in the groundwater samples obtained in 2005 and 2008. No fungicides were detected. In relation to the pesticides detected, degradate compounds were as or more likely to be detected than applied (parent) compounds. The detected pesticides chiefly reflected herbicides commonly used in urban settings for non-specific weed control or insecticides used for nonspecific haustellate insects (insects with specialized mouthparts for sucking liquid) or termite-specific control. Detected pesticides included a combination of pesticides currently (2008) in use, banned or under highly restricted use, and some that had replaced the banned or restricted-use pesticides. The presence of banned and restricted-use pesticides illustrates their continued persistence and resistance to complete degradation in the environment. The presence of the replacement pesticides indicates the susceptibility of the surficial aquifer to contamination irrespective of the changes in the pesticides used. A

  11. Tobacco retail outlet advertising practices and proximity to schools, parks and public housing affect Synar underage sales violations in Washington, DC.

    Science.gov (United States)

    Kirchner, Thomas R; Villanti, Andrea C; Cantrell, Jennifer; Anesetti-Rothermel, Andrew; Ganz, Ollie; Conway, Kevin P; Vallone, Donna M; Abrams, David B

    2015-03-01

    To examine the cross-sectional association between illicit sales of tobacco to minors, Washington DC tobacco outlet advertising practices, retail store type, the demographic make-up of the area surrounding each outlet, and the proximity of each outlet to high schools, recreational parks and public housing. Seven hundred and fifty tobacco outlets in the DC area, n=347 of which were randomly selected for inspection by the Synar Inspection Program in 2009-2010. The presence of tobacco advertisements on the interior and exterior of each outlet, and illicit tobacco sales to Synar Inspection Program youth volunteers. The presence of tobacco advertisements on the exterior of gas stations was much greater than on other retail store types (OR=6.68; 95% CI 4.05 to 11.01), as was the absence of any advertisements at bars or restaurants that sold tobacco (OR=0.33; 95% CI 0.22 to 0.52). Exterior tobacco advertisements were also more likely in predominantly African-American areas of the city (OR=3.11; 95% CI 2.28 to 4.25), and particularly likely on storefronts located closer to parks (OR=1.87; 95% CI 1.06 to 3.28). Illicit sales to minors were more common at gas stations (OR=3.01; 95% CI 1.5 to 6.3), outlets that displayed exterior tobacco advertisements closer to parks (OR=3.36; 95% CI 1.38 to 8.21), and outlets located closer to high schools in majority African-American block groups (OR=1.29; 95% CI 1.07 to 1.58). Findings demonstrate that while illicit tobacco sales to minors are occurring at acceptably low rates by Synar standards, illicit sales vary considerably by retail store type, advertising approach and proximity to high schools, parks and African-American residential areas. Future work may help inform regulatory efforts to reduce youth access at the neighbourhood, city, state and national levels. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Seasonal Changes in Sleep Duration in African American and African College Students Living In Washington, D.C.

    Directory of Open Access Journals (Sweden)

    Janna Volkov

    2007-01-01

    Full Text Available Duration of nocturnal melatonin secretion, a marker of “biological night” that relates to sleep duration, is longer in winter than in summer in patients with seasonal affective disorder (SAD, but not in healthy controls. In this study of African and African American college students, we hypothesized that students who met criteria for winter SAD or subsyndromal SAD (S-SAD would report sleeping longer in winter than in summer. In addition, based on our previous observation that Africans report more “problems” with change in seasons than African Americans, we expected that the seasonal changes in sleep duration would be greater in African students than in African American students. Based on Seasonal Pattern Assessment Questionnaire (SPAQ responses, African American and African college students in Washington, D.C. (N = 575 were grouped into a winter SAD/S-SAD group or a no winter diagnosis group, and winter and summer sleep length were determined. We conducted a 2 (season × 2 (sex × 2 (ethnicity × 2 (winter diagnosis group ANCOVA on reported sleep duration, controlling for age. Contrary to our hypothesis, we found that African and African American students with winter SAD/S-SAD report sleeping longer in the summer than in the winter. No differences in seasonality of sleep were found between African and African American students. Students with winter SAD or S-SAD may need to sacrifice sleep duration in the winter, when their academic functioning/efficiency may be impaired by syndromal or subsyndromal depression, in order to meet seasonally increased academic demands.

  13. Crafting glass vessels: current research on the ancient glass collections in the Freer Gallery of Art, Washington, D.C.

    Science.gov (United States)

    Nagel, Alexander; McCarthy, Blythe; Bowe, Stacy

    Our knowledge of glass production in ancient Egypt has been well augmented by the publication of recently excavated materials and glass workshops, but also by more recent materials analysis, and experiments of modern glass-makers attempting to reconstruct the production process of thin-walled coreformed glass vessels. From the mounting of a prefabricated core to the final glass product our understanding of this profession has much improved. The small but well preserved glass collection of the Freer Gallery of Art in Washington, D.C. is a valid tool for examining and studying the technology and production of ancient Egyptian core formed glass vessels. Charles Lang Freer (1854-1919) acquired most of the material from Giovanni Dattari in Cairo in 1909. Previously the glass had received only limited discussion, suggesting that most of these vessels were produced in the 18th Dynasty in the 15th and 14th centuries BCE, while others date from the Hellenistic period and later. In an ongoing project we conducted computed radiography in conjunction with qualitative x-ray fluorescence analysis on a selected group of vessels to understand further aspects of the ancient production process. This paper will provide an overview of our recent research and present our data-gathering process and preliminary results. How can the examinations of core formed glass vessels in the Freer Gallery contribute to our understanding of ancient glass production and technology? By focusing on new ways of looking at old assumptions using the Freer Gallery glass collections, we hope to increase understanding of the challenges of the production process of core-vessel technology as represented by these vessels.

  14. Area-Efficiency Trade-Offs in Integrated Switched-Capacitor DC-DC Converters

    DEFF Research Database (Denmark)

    Spliid, Frederik Monrad; Larsen, Dennis Øland; Knott, Arnold

    2016-01-01

    , based on the total chip area is developed. This algorithm also determines the optimal number of parallel phases in the converter, based on an estimate of power consumption in flip- flop based clock circuits. By these means the maximum achievable efficiency as a function of chip area is estimated...

  15. Structure, age, and tectonic setting of a multiply reactivated shear zone in the piedmont in Washington, D.C., and vicinity

    Science.gov (United States)

    Fleming, A.H.; Drake, Avery A.

    1998-01-01

    The Rock Creek shear zone is the dominant tectonic feature in the Piedmont in Washington, D.C. and adjacent parts of Maryland, has an exposed length of 25 km, and a width of up to 3 km. The shear zone is characterized by a complicated composite fabric produced by the imposition of both ductile and brittle structures as well as the reactivation, transposition, and folding of older structures during subsequent antithetic displacement. At least five main types of structural elements are discernible and include: 1) relict, medium- to coarse-grained mylonitic foliation and related structures produced by sinistral shearing under at least middle amphibolite facies conditions; 2) a ductile fault zone having an apparent sinistral displacement of at least several km and an unknown, but possibly significant component of upward throw of the east wall; 3) pervasive, fine-grained ultramylonitic foliation associated with quartz ribbons and late oblique shear bands, generated by dextral shearing under thermal conditions that appear to have progressed from middle greenschist to sub-greenschist (semi-brittle); 4) a system of oblique-(west wall up) and dextralship faults localized chiefly within a tectonic me??lange at the junction of two major strands, and whose motion spanned the ductile-brittle transition; and 5) a system of post-Cretaceous thrust faults that cut Coastal Plain rocks as young as Quaternary as well as the previously deformed crystalline rocks. The first two sets of structures are of probable Ordovician age and are thus believed to coincide with the Taconic event, which produced regional middle to upper amphibolite facies metamorphism, widespread plutonism, and extensive southwest-vergent fold phases in this area. In contrast, the dextral shearing and faulting were generated during final thermal cooling and represent the latest Paleozoic penetrative deformation that affected this area. They are very likely Alleghanian because of their great similarity to other better

  16. Predicting the timing of cherry blossoms in Washington, DC and Mid-Atlantic States in response to climate change.

    Science.gov (United States)

    Chung, Uran; Mack, Liz; Yun, Jin I; Kim, Soo-Hyung

    2011-01-01

    Cherry blossoms, an icon of spring, are celebrated in many cultures of the temperate region. For its sensitivity to winter and early spring temperatures, the timing of cherry blossoms is an ideal indicator of the impacts of climate change on tree phenology. Here, we applied a process-based phenology model for temperate deciduous trees to predict peak bloom dates (PBD) of flowering cherry trees (Prunus×yedoensis 'Yoshino' and Prunus serrulata 'Kwanzan') in the Tidal Basin, Washington, DC and the surrounding Mid-Atlantic States in response to climate change. We parameterized the model with observed PBD data from 1991 to 2010. The calibrated model was tested against independent datasets of the past PBD data from 1951 to 1970 in the Tidal Basin and more recent PBD data from other locations (e.g., Seattle, WA). The model performance against these independent data was satisfactory (Yoshino: r(2) = 0.57, RMSE = 6.6 days, bias = 0.9 days and Kwanzan: r(2) = 0.76, RMSE = 5.5 days, bias = -2.0 days). We then applied the model to forecast future PBD for the region using downscaled climate projections based on IPCC's A1B and A2 emissions scenarios. Our results indicate that PBD at the Tidal Basin are likely to be accelerated by an average of five days by 2050 s and 10 days by 2080 s for these cultivars under a mid-range (A1B) emissions scenario projected by ECHAM5 general circulation model. The acceleration is likely to be much greater (13 days for 2050 s and 29 days for 2080s) under a higher (A2) emissions scenario projected by CGCM2 general circulation model. Our results demonstrate the potential impacts of climate change on the timing of cherry blossoms and illustrate the utility of a simple process-based phenology model for developing adaptation strategies to climate change in horticulture, conservation planning, restoration and other related disciplines.

  17. Predicting the timing of cherry blossoms in Washington, DC and Mid-Atlantic States in response to climate change.

    Directory of Open Access Journals (Sweden)

    Uran Chung

    Full Text Available Cherry blossoms, an icon of spring, are celebrated in many cultures of the temperate region. For its sensitivity to winter and early spring temperatures, the timing of cherry blossoms is an ideal indicator of the impacts of climate change on tree phenology. Here, we applied a process-based phenology model for temperate deciduous trees to predict peak bloom dates (PBD of flowering cherry trees (Prunus×yedoensis 'Yoshino' and Prunus serrulata 'Kwanzan' in the Tidal Basin, Washington, DC and the surrounding Mid-Atlantic States in response to climate change. We parameterized the model with observed PBD data from 1991 to 2010. The calibrated model was tested against independent datasets of the past PBD data from 1951 to 1970 in the Tidal Basin and more recent PBD data from other locations (e.g., Seattle, WA. The model performance against these independent data was satisfactory (Yoshino: r(2 = 0.57, RMSE = 6.6 days, bias = 0.9 days and Kwanzan: r(2 = 0.76, RMSE = 5.5 days, bias = -2.0 days. We then applied the model to forecast future PBD for the region using downscaled climate projections based on IPCC's A1B and A2 emissions scenarios. Our results indicate that PBD at the Tidal Basin are likely to be accelerated by an average of five days by 2050 s and 10 days by 2080 s for these cultivars under a mid-range (A1B emissions scenario projected by ECHAM5 general circulation model. The acceleration is likely to be much greater (13 days for 2050 s and 29 days for 2080s under a higher (A2 emissions scenario projected by CGCM2 general circulation model. Our results demonstrate the potential impacts of climate change on the timing of cherry blossoms and illustrate the utility of a simple process-based phenology model for developing adaptation strategies to climate change in horticulture, conservation planning, restoration and other related disciplines.

  18. Attitudes, perceptions and behaviours towards HIV testing among African-American and East African immigrant women in Washington, DC: implications for targeted HIV testing promotion and communication strategies.

    Science.gov (United States)

    De Jesus, Maria; Carrete, Claudia; Maine, Cathleen; Nalls, Patricia

    2015-12-01

    The objective of the study was to examine and compare the HIV testing attitudes, perceptions and behaviours between African-American and East African immigrant women in the Washington, DC metropolitan area. Adopting an inductive, qualitative methodological approach, we conducted a total of 40 in-depth, semistructured interviews between October 2012 and March 2013. Qualitative thematic analysis was used to analyse the data. Overall, African-American women held more favourable views towards HIV testing than East African immigrant women. Very few East African immigrant women sought HIV testing intentionally. The majority of East African participants were tested inadvertently, while others tested for immigration-related or employment-related purposes. There were many barriers that impede women from seeking an HIV test including negative assumptions (eg, "Getting an HIV test implies that I am HIV positive"), negative emotions (eg, "Fear of being diagnosed with HIV and what this will mean for me") and potential negative reactions from partner or others (eg, "Getting an HIV test can signal distrust, disrespect, or infidelity"). There were nuances in how each group articulated some of these barriers and East African women expressed unique concerns that originated from experiences in their home countries. The study shed light into the complexity of factors that constrain women from presenting themselves voluntarily for an HIV test and highlighted the nuances between African-American and East African perceptions. Implications of findings for effective targeted HIV screening promotion and communication strategies among these groups of women are discussed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  19. Awareness, Willingness, and Use of Pre-exposure Prophylaxis Among Men Who Have Sex With Men in Washington, DC and Miami-Dade County, FL: National HIV Behavioral Surveillance, 2011 and 2014.

    Science.gov (United States)

    Patrick, Rudy; Forrest, David; Cardenas, Gabriel; Opoku, Jenevieve; Magnus, Manya; Phillips, Gregory; Greenberg, Alan; Metsch, Lisa; Kharfen, Michael; LaLota, Marlene; Kuo, Irene

    2017-07-01

    Despite the effectiveness of oral pre-exposure prophylaxis (PrEP) for HIV prevention, knowledge, and uptake of this new prevention intervention over time has not been fully studied. Using NHBS data from 2 urban areas highly impacted by HIV, we examined awareness, use, and willingness to use daily oral PrEP and factors associated with willingness to take oral PrEP among men who have sex with men (MSM) over time. MSM from Washington, DC and Miami, FL were recruited in 2011 and 2014 using venue-based sampling. Participants completed behavioral surveys and HIV testing. Awareness, use, and willingness to use oral PrEP were examined. Demographic and behavioral correlates of being "very likely" to use PrEP in 2011 and 2014 were assessed. PrEP awareness increased from 2011 to 2014 in both cities (DC: 39.1%-73.8% and Miami: 19.4%-41.2%), but use remained low in 2014 (DC: 7.7%; Miami: 1.4%). Being very likely to use PrEP decreased over time in DC (61%-48%), but increased in Miami (48%-60%). In DC, minority race was associated with increased odds of being very likely to use PrEP, whereas reduced odds of being very likely to use PrEP was observed for MSM with 1 or 2-5 partners versus having 6+ partners. In Miami, a higher proportion of white versus Hispanic MSM reported being very likely to use PrEP in 2011, but this observation was reversed in 2014. Geographic differences in awareness, use, and willingness to use PrEP indicate that innovative strategies are needed to educate MSM about this effective prevention strategy.

  20. FLOODPLAIN MAPPING SUBMISSION FOR LEWIS COUNTY, WASHINGTON AND INCORPORATED AREAS

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  1. FLOODPLAIN, CLARK COUNTY, WASHINGTON (AND INCORPORATED AREAS), USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the...

  2. Factors affecting Navy Working Capital Fund (NWCF) net operating result: a case study of Naval Facilities Engineering Command Washington, Washington D.C.

    OpenAIRE

    Duong, Tamanh Q.; Uribe, Juan C.; Johnson, Greg R.

    2009-01-01

    Approved for public release, distribution unlimited MBA Professional Report Over the past four years, Naval Facilities Engineering Command (NAVFAC) Washington has encountered net operating result (NOR) losses not anticipated in the Navy Working Capital Fund (NWCF) budget. These unanticipated losses primarily stemmed from three major factors associated with financial operations. The first factor is the creation of stabilized rates that turned out to be insufficient during fiscal years...

  3. 78 FR 32131 - Revision to the Washington State Implementation Plan; Tacoma-Pierce County Nonattainment Area

    Science.gov (United States)

    2013-05-29

    ... approving State Implementation Plan (SIP) revisions submitted by the Washington Department of Ecology (Ecology) dated November 28, 2012. The EPA's final rulemaking approves two revisions to the SIP. First, the... related to the Tacoma-Pierce County nonattainment area for the 2006 fine particulate matter (PM 2.5...

  4. Understanding Climate Policy Data Needs. NASA Carbon Monitoring System Briefing: Characterizing Flux Uncertainty, Washington D.C., 11 January 2012

    Science.gov (United States)

    Brown, Molly E.; Macauley, Molly

    2012-01-01

    Climate policy in the United States is currently guided by public-private partnerships and actions at the local and state levels. This mitigation strategy is made up of programs that focus on energy efficiency, renewable energy, agricultural practices and implementation of technologies to reduce greenhouse gases. How will policy makers know if these strategies are working, particularly at the scales at which they are being implemented? The NASA Carbon Monitoring System (CMS) will provide information on carbon dioxide fluxes derived from observations of earth's land, ocean and atmosphere used in state of the art models describing their interactions. This new modeling system could be used to assess the impact of specific policy interventions on CO2 reductions, enabling an iterative, results-oriented policy process. In January of 2012, the CMS team held a meeting with carbon policy and decision makers in Washington DC to describe the developing modeling system to policy makers. The NASA CMS will develop pilot studies to provide information across a range of spatial scales, consider carbon storage in biomass, and improve measures of the atmospheric distribution of carbon dioxide. The pilot involves multiple institutions (four NASA centers as well as several universities) and over 20 scientists in its work. This pilot study will generate CO2 flux maps for two years using observational constraints in NASA's state-of -the-art models. Bottom-up surface flux estimates will be computed using data-constrained land and ocean models; comparison of the different techniques will provide some knowledge of uncertainty in these estimates. Ensembles of atmospheric carbon distributions will be computed using an atmospheric general circulation model (GEOS-5), with perturbations to the surface fluxes and to transport. Top-down flux estimates will be computed from observed atmospheric CO2 distributions (ACOS/GOSAT retrievals) alongside the forward-model fields, in conjunction with an

  5. Volatile Organic Compound Investigation Results, 300 Area, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Robert E.; Williams, Bruce A.; Smith, Ronald M.

    2008-07-07

    Unexpectedly high concentrations of volatile organic compounds (VOC) were discovered while drilling in the unconfined aquifer beneath the Hanford Site’s 300 Area during 2006. The discovery involved an interval of relatively finer-grained sediment within the unconfined aquifer, an interval that is not sampled by routine groundwater monitoring. Although VOC contamination in the unconfined aquifer has been identified and monitored, the concentrations of newly discovered contamination are much higher than encountered previously, with some new results significantly higher than the drinking water standards. The primary contaminant is trichloroethene, with lesser amounts of tetrachloroethene. Both chemicals were used extensively as degreasing agents during the fuels fabrication process. A biological degradation product of these chemicals, 1,2-dichloroethene, was also detected. To further define the nature and extent of this contamination, additional characterization drilling was undertaken during 2007. Four locations were drilled to supplement the information obtained at four locations drilled during the earlier investigation in 2006. The results of the combined drilling indicate that the newly discovered contamination is limited to a relatively finer-grained interval of Ringold Formation sediment within the unconfined aquifer. The extent of this contamination appears to be the area immediately east and south of the former South Process Pond. Samples collected from the finer-grained sediment at locations along the shoreline confirm the presence of the contamination near the groundwater/river interface. Contamination was not detected in river water that flows over the area where the river channel potentially incises the finer-grained interval of aquifer sediment. The source for this contamination is not readily apparent. A search of historical documents and the Hanford Waste Information Data System did not provide definitive clues as to waste disposal operations and

  6. Application and evaluation of the WRF-CMAQ modeling system to the 2011 DISCOVER-AQ Baltimore-Washington D.C. study

    Science.gov (United States)

    Appel, W.; Gilliam, R. C.; Pouliot, G. A.; Godowitch, J. M.; Pleim, J.; Hogrefe, C.; Kang, D.; Roselle, S. J.; Mathur, R.

    2013-12-01

    The DISCOVER-AQ project (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality), is a joint collaboration between NASA, U.S. EPA and a number of other local organizations with the goal of characterizing air quality in urban areas using satellite, aircraft, vertical profiler and ground based measurements (http://discover-aq.larc.nasa.gov). In July 2011, the DISCOVER-AQ project conducted intensive air quality measurements in the Baltimore, MD and Washington, D.C. area in the eastern U.S. To take advantage of these unique data, the Community Multiscale Air Quality (CMAQ) model, coupled with the Weather Research and Forecasting (WRF) model is used to simulate the meteorology and air quality in the same region using 12-km, 4-km and 1-km horizontal grid spacings. The goal of the modeling exercise is to demonstrate the capability of the coupled WRF-CMAQ modeling system to simulate air quality at fine grid spacings in an urban area. Development of new data assimilation techniques and the use of higher resolution input data for the WRF model have been implemented to improve the meteorological results, particularly at the 4-km and 1-km grid resolutions. In addition, a number of updates to the CMAQ model were made to enhance the capability of the modeling system to accurately represent the magnitude and spatial distribution of pollutants at fine model resolutions. Data collected during the 2011 DISCOVER-AQ campaign, which include aircraft transects and spirals, ship measurements in the Chesapeake Bay, ozonesondes, tethered balloon measurements, DRAGON aerosol optical depth measurements, LIDAR measurements, and intensive ground-based site measurements, are used to evaluate results from the WRF-CMAQ modeling system for July 2011 at the three model grid resolutions. The results of the comparisons of the model results to these measurements will be presented, along with results from the various sensitivity simulations

  7. Characteristics of Black Men Who Have Sex With Men in Baltimore, Philadelphia, and Washington, D.C.: Geographic Diversity in Socio-Demographics and HIV Transmission Risk.

    Science.gov (United States)

    German, Danielle; Brady, Kathleen; Kuo, Irene; Opoku, Jenevieve; Flynn, Colin; Patrick, Rudy; Park, Ju Nyeong; Adams, Joella; Carroll, Makeda; Simmons, Ron; Smith, Carlton R; Davis, Wendy W

    2017-07-01

    Baltimore, Philadelphia, and Washington, DC are geographically proximate cities with high HIV prevalence, including among black men who have sex with men (BMSM). Using data collected among BMSM in CDC's National HIV Behavioral Surveillance project, we compared socio-demographic characteristics, HIV risk behaviors, and service utilization to explore similarities and differences that could inform local and regional HIV intervention approaches. BMSM were recruited through venue time location sampling, June-December, 2011. Participants completed identical socio-behavioral surveys and voluntary HIV testing. Analyses were conducted among the full sample and those aged 18-24. Participants included 159 (DC), 364 (Baltimore), and 331 (Philadelphia) eligible BMSM. HIV prevalence was 23.1% (DC), 48.0% (Baltimore), 14.6% (Philadelphia) with 30.6%, 69.0%, 33.3% unrecognized HIV infection, respectively. Among BMSM 18-24, HIV prevalence was 11.1% (DC), 38.9% (Baltimore), 9.6% (Philadelphia) with unrecognized HIV infection 0.0%, 73.8%, 60.0% respectively. Compared with the other 2 cities, Baltimore participants were less likely to identify as gay/homosexual; more likely to report unemployment, incarceration, homelessness, sex exchange; and least likely to use the internet for partners. DC participants were more likely to have a college degree and employment. Philadelphia participants were more likely to report gay/homosexual identity, receptive condomless anal sex, having only main partners, and bars/clubs as partner meeting places. Sexually transmitted disease testing was universally low. Analyses showed especially high HIV prevalence among BMSM in Baltimore including among young BMSM. Socio-demographic characteristics and HIV infection correlates differed across cities but unrecognized HIV infection and unknown partner status were universally high.

  8. Low temperature geothermal resource evaluation of the Moses Lake-Ritzville-Connell area, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Widness, S.

    1983-11-01

    The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given. A technique developed by Biggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG).

  9. 78 FR 53237 - Establishment of Area Navigation (RNAV) Routes; Washington, DC

    Science.gov (United States)

    2013-08-29

    ... Owners and Pilots Association (AOPA) commented that they do not support the establishment of T-287 and T-299 and advocated that the FAA withdraw the proposal. AOPA contended that aircraft already are able to.... AOPA further contended that T-routes must be established within Class B airspace to retain an...

  10. Evidence for ongoing introduction of non-native earthworms in the Washington, DC metropolitan area

    Science.gov (United States)

    Mac A. Callaham; Bruce A. Snyder; Samuel W. James; Erik T. Oberg

    2016-01-01

    Earthworm introductions and invasions are ongoing, with significant consequences for ecological characteristics and function where populations of invasive species reach high densities. In North America the influx of people, goods and materials to coastal cities has long been recognized to be related to introduction and establishment of...

  11. 78 FR 29615 - Establishment of Area Navigation (RNAV) Routes; Washington, DC

    Science.gov (United States)

    2013-05-21

    ... via a direct routing to the HACKS intersection, thus reducing miles flown for RNAV-equipped aircraft...) of 11,000 feet MSL. The new T-routes provide more efficient and predictable routing for aircraft... regulation is within the scope of that authority as it establishes RNAV routes to enhance the safe and...

  12. 78 FR 10562 - Proposed Establishment of Area Navigation (RNAV) Routes; Washington, DC

    Science.gov (United States)

    2013-02-14

    ... the RAMAY, VA, WP. It would provide an alternate route for jet route J-149 via a direct routing to the...,000 feet MSL. The T-routes would provide more efficient and predictable routing for aircraft utilizing... authority as it establishes RNAV routes as required to preserve the safe and efficient flow of air traffic...

  13. Metropolitan Washington Area Water Supply Study. Main Report. Maryland, Virginia and the District of Columbia.

    Science.gov (United States)

    1983-09-01

    release, distribution unlimited. 17. DISTRIBUTION STATEMENT (of Cho aborat sittore in Block t, if fforoU lice Reprt) IS. SUPPLEMENTARY NOTES 19. KEY...Dam and Lice , Maryland, are hereby authorized substantially in accordance with the Adequate land use controls would bb recommendations, of the...Planning for the Metropolitan Washington Area Gill Examination of Water Quality and Potability H Bloomington Lake Reform- H-I Background Information ulation

  14. Mobile Health Technology Can Objectively Capture Physical Activity (PA) Targets Among African-American Women Within Resource-Limited Communities-the Washington, D.C. Cardiovascular Health and Needs Assessment.

    Science.gov (United States)

    Thomas, S; Yingling, L; Adu-Brimpong, J; Mitchell, V; Ayers, C R; Wallen, G R; Peters-Lawrence, M; Brooks, A T; Sampson, D M; Wiley, K L; Saygbe, J; Henry, J; Johnson, A; Graham, A; Graham, L; Powell-Wiley, T M

    2016-12-02

    Little is understood about using mobile health (mHealth) technology to improve cardiovascular (CV) health among African-American women in resource-limited communities. We conducted the Washington, D.C. CV Health and Needs Assessment in predominantly African-American churches in city wards 5, 7, and 8 with the lowest socioeconomic status based on community-based participatory research (CBPR) principles. The assessment measured CV health factors: body mass index (BMI), fasting blood glucose and cholesterol, blood pressure, fruit/vegetable (F/V) intake, physical activity (PA), and smoking. Participants were trained to use a PA monitoring wristband to measure 30 days of PA, wirelessly upload the PA data to hubs at the participating churches, and access their data from a church/home computer. CV health factors were compared across weight classes. Among females (N = 78; 99 % African-American; mean age = 59 years), 90 % had a BMI categorized as overweight/obese. Across weight classes, PA decreased and self-reported sedentary time (ST) increased (p ≤ 0.05). Diastolic blood pressure and glucose increased across weight classes (p ≤ 0.05); however, cholesterol, glucose, and BP were near intermediate CV health goals. Decreased PA and increased ST are potential community intervention targets for overweight and obese African-American women in resource-limited Washington D.C. areas. mHealth technology can assist in adapting CBPR intervention resources to improve PA for African-American women in resource-limited communities.

  15. Βιβλιοκρισία:A. WEYL CARR - A. NICOLAIDES (eds., Asinou across Time: Studies in the Architecture and Murals of the Panagia Phorbiotissa, Cyprus. Dumbarton Oaks Studies, 43. Washington, DC:, 2012.

    Directory of Open Access Journals (Sweden)

    Bασιλική ΦΩΣΚΟΛΟΥ

    2015-04-01

    Full Text Available Bιβλιοκρισία:Annemarie Weyl Carr -Andréas Nicolaïdès (eds., Asinou across Time: Studies in the Architecture and Murals of the Panagia Phorbiotissa, Cyprus. Dumbarton Oaks Studies, 43. Washington, DC: Dumbarton Oaks Research Library and Collection, 2012. Pp. xii, 431.  ISBN 9780884023494.

  16. Deployment of Low-Cost, Carbon Dioxide Sensors throughout the Washington Metropolitan Area - The Capital Climate Initiative

    Science.gov (United States)

    Caine, Kristen M.; Bailey, D. Michelle; Houston Miller, J.

    2016-04-01

    According to the IPCC from 1995 to 2005, atmospheric carbon dioxide (CO2) concentrations increased by 19 ppm, the highest average growth rate recorded for any decade since measurements began in the 1950s. Due to its ability to influence global climate change, it is imperative to continually monitor carbon dioxide emission levels, particularly in urban areas where some estimate in excess of 75% of total greenhouse gas emissions occur. Although high-precision sensors are commercially available, these are not cost effective for mapping a large spatial area. A goal of this research is to build out a network of sensors that are accurate and precise enough to provide a valuable data tool for accessing carbon emissions from a large, urban area. This publically available greenhouse gas dataset can be used in numerous environmental assessments and as validation for remote sensing products. It will also be a valuable teaching tool for classes at our university and will promote further engagement of K-12 students and their teachers through education and outreach activities. Each of our sensors (referred to as "PiOxides") utilizes a non-dispersive infrared (NDIR) sensor for the detection of carbon dioxide along with a combination pressure/temperature/humidity sensor. The collection of pressure and temperature increases the accuracy and precision of the CO2 measurement. The sensors communicate using a serial interfaces with a Raspberry Pi microcontroller. Each PiOxide is connected to a website that leverages recent developments in open source GIS tools. In this way, data from individual sensors can be followed individually or aggregated to provide real-time, spatially-resolved data of CO2 trends across a broad area. Our goal for the network is to expand across the entire DC/Maryland/Virginia Region through partnerships with private and public schools. We are also designing GHG Bluetooth beacons that may be accessed by mobile phone users in their vicinity. In two additional

  17. Use of Multiple DC Magnetron Deposition Sources for Uniform Coating of Large Areas (Preprint)

    Science.gov (United States)

    2009-06-01

    2005- 1 June 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER FA9451-04-C-0067 DF297548 Use of multiple DC magnetron deposition sources for...thickness at some point on the substrate plane to yield a relative thickness distribution or it can be used to find the ratio Mlm which will be useful... Mlm of the material deposited in each area, is shown in columns 3 though 5, for the three sources.. For example, within the area from the center of the

  18. Three-Dimensional Groundwater Models of the 300 Area at the Hanford Site, Washington State

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Mark D.; Rockhold, Mark L.; Thorne, Paul D.; Chen, Yousu

    2008-09-01

    Researchers at Pacific Northwest National Laboratory developed field-scale groundwater flow and transport simulations of the 300 Area to support the 300-FF-5 Operable Unit Phase III Feasibility Study. The 300 Area is located in the southeast portion of the U.S. Department of Energy’s Hanford Site in Washington State. Historical operations involving uranium fuel fabrication and research activities at the 300 Area have contaminated engineered liquid-waste disposal facilities, the underlying vadose zone, and the uppermost aquifer with uranium. The main objectives of this research were to develop numerical groundwater flow and transport models to help refine the site conceptual model, and to assist assessment of proposed alternative remediation technologies focused on the 300 Area uranium plume.

  19. All Prime Contract Awards by State or Country, Place, and Contractor. Part 6 (Washington, DC-Palm Beach, Florida)

    Science.gov (United States)

    1990-01-01

    00 0 0 0 0 0 0 0 0 C0 000 0 0 0 0N IM0-4 of N4. 4 04C 44 04 0 00 Co 00 0 0 00 )w cDc tD to to 0w w w W (a 0 v 1-4: W 1 M-4 310000 r- Q 40 UN 00 O " f...4-4 .400 40 ZUI-Z * a a 4V) 4Y~if 40 a0 .4 td 40 -40’ w4 a Mwwl- a 0 0 0 00 0 0 0 0 0 4 CA a W-4 3a 2 2 22 2z 2 Z 2 22 ZZ 3 * 04-4 U 4c a 0 a: a0 co 0...0 0 0 IN a 0 C 0 lm 00 0,04000000000 0 0 0ly 0011i o m -4 0 cr .0-4WW WW W -4 VC)C)U ,cC)C nmr # c VC) .0 0’a 0 -N eŘ N . C4 .44 NN 00000000.000-gin

  20. Abundance of Apple Maggot, Rhagoletis pomonella, Across Different Areas in Central Washington, with Special Reference to Black-Fruited Hawthorns

    OpenAIRE

    Yee, Wee L.; Klaus, Michael W.; Cha, Dong H.; Charles E Linn; Goughnour, Robert B.; Feder, Jeffrey L.

    2012-01-01

    The apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), infests non-commercial apple (Malus domestica (Borkh.) Borkh.) and native black-fruited hawthorns (mostly Crataegus douglasii Lindl.) in central Washington, but little has been published on the abundance of the fly in this region. In this paper, the abundance of R. pomonella across different sites near apple-growing areas in central Washington is documented in order to assess the threat of the fly to commercial apple o...

  1. Measurements and models of greenhouse gas emissions and pollutant fluxes in the Baltimore/Washington Area.

    Science.gov (United States)

    Dickerson, R. R.; Salawitch, R. J.; Canty, T. P.; Shepson, P. B.; Ahn, D.; Ren, X.; He, H.; Karion, A.; Allen, D. J.; Hall, D.

    2016-12-01

    Building on the lifetime accomplishments of Donald H. Stedman, we present results from a combined measurement and modeling program to quantify the flux of pollutants, both short and long lived, from the Baltimore/Washington area. Urban areas are a dominant and growing source of emissions leading to photochemical smog and climate forcing, but the rate of release of species such as CO, NOx, SO2, CO2, and CH4 remains uncertain. This presentation will summarize recent results that estimate the flux of these species, the relative importance of various sources, and the trends. NOx, CO, VOC's and SO2 have demonstrably improved in recent years, but such trends are not clear for greenhouse gases. New understanding of relative contribution from oil and gas operations, electricity generation, and mobile sources is presented and the role of outliers in the distribution of sources or "gross emitters" is discussed.

  2. Shrub-inhabiting insects of the 200 Area Plateau, southcentral Washington.

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, L.E.

    1979-10-01

    This study characterizes the insects (including spiders) associated with major shrubs of the 200 Area Plateau on the Hanford Site in southcentral Washington. Big sagebrush (Artemisia tridentata), rabbitbrush (Chrysothamnus sp.) and hopsage (Grayia spinosa) were the three shrubs included in the study. Hemiptera (true bugs) and homoptera (bugs) were the two groups most abundant on sagebrush. Homoptera and Araneida (spiders) were the common inhabitants of rabbitbrush, and Orthoptera (grasshoppers), Coleoptera (beetles), and Araneida the taxa most frequently collected from hopsage. A discussion of the effects of insects on western native shrubs is included. None of the insect populations appeared to threaten the stability of shrub stands, which is important because of the erodability of 200 Area soils.

  3. Fontan-Associated Liver Disease: Proceedings from the American College of Cardiology Stakeholders Meeting, October 1 to 2, 2015, Washington DC.

    Science.gov (United States)

    Daniels, Curt J; Bradley, Elisa A; Landzberg, Mike J; Aboulhosn, Jamil; Beekman, Robert H; Book, Wendy; Gurvitz, Michelle; John, Anitha; John, Binu; Marelli, Ariane; Marino, Bradley S; Minich, L LuAnn; Poterucha, John J; Rand, Elizabeth B; Veldtman, Gruschen R

    2017-12-26

    Over the past decade, as the majority of patients with single ventricle anatomy who have undergone the Fontan operation reach adulthood, a newly recognized disease process, Fontan-associated liver disease (FALD), has emerged. FALD is an extracardiac complication that may lead to substantial comorbid disease and premature mortality. The risk factors, pathophysiology, longitudinal consequences, and therapeutic options related to FALD remain poorly defined. Although we recognize that Fontan circulatory properties are associated with extracardiac organ dysfunction, numerous gaps in our understanding of the nature of this relationship exist. Such extracardiac manifestations, in addition to other late complications of the circulation, can significantly affect quality of life and healthcare use. Therefore, to initiate a formal evaluation of FALD, the American College of Cardiology (ACC) sponsored a stakeholders meeting on October 1 to 2, 2015, in Washington, DC. The goal of the meeting was to bring together subspecialty experts in the fields of adult and pediatric hepatology, congenital cardiology (adult congenital and pediatric cardiology), heart failure/transplant, epidemiology, and cardiothoracic surgery, as well as patient advocates, patients, parents of children and young adults who have had the Fontan procedure, and research organizations and societies to discuss the current state of FALD. Topics included gaps in knowledge, optimal care, research opportunities and barriers, and sound practices to guide providers, patients, and families. This report summarizes findings from the stakeholders meeting and seeks to establish a platform for understanding and addressing FALD. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  4. Summary Proceedings of the Future Navigation Systems Planning Conference, held 3-4 August 1982, Washington, DC.

    Science.gov (United States)

    1982-09-01

    System Planning Director of Aviation Policy and Plans, FAA 4:45 Adjourn Wednesday. August 4. 1982 9:00 Department of Transportation David C. Scull ...even across the U.S. in the en route system. It is widely used internationally, often in conjunc- tion with inertial navigation systems. It requires an...services if the signal sources were to be disabled. Inertial navigation systems are now authorized as a sole means of navigation in over-ocean areas. INS

  5. The Anniversary of the First Public Announcement of the Successful Test of Fission Proceedings (50th) Held in Washington, DC on 17 January 1989

    Science.gov (United States)

    1989-01-17

    Larson Energy Consultant Dr. Theodore P. Perros , Chairman Chemistry Department The George Washingtbn University Dr. Sam Rothman Professor and... Perros Ms. Nancy Jo Nicholas Chemistry Department I Graduate Student The George Washington Department of Physics University The George Washington

  6. Raptors of the Hanford Site and nearby areas of southcentral Washington

    Energy Technology Data Exchange (ETDEWEB)

    Fitzner, R.E.; Rickard, W.H.; Cadwell, L.L.; Rogers, L.E.

    1981-05-01

    This report is concerned with the birds of prey which use the Hanford Site not only during the nesting season but throughout the year. An ecological treatment of five nesting owls (great horned, long-eared, short-eared, barn and burrowing) and five nesting hawks (marsh hawk, red-tailed hawk, Swainson's hawk, prairie falcon and American kestrel) is provided and supportive information on non-nesting species is presented. Factors which control raptor densities and population dynamics throughout all seasons of the year are discussed. Information is also provided for raptors from other areas of southcentral Washington in order to yield a comprehensive picture of how the Hanford Site fits in with regional bird of prey populations. The following were the objectives of this study: (1) to determine the numbers of birds of prey nesting on the Hanford Site, (2) to document the reproductive chronology of each nesting raptor species, (3) to provide analyses of food habits of birds of prey on the Hanford Site coupled with prey abundance data, (4) to determine the productivity of the dominant large birds of prey on the Hanford Site, (5) to determine the distribution and land use patterns of all raptors on the Hanford Site, (6) to determine the kinds and relative abundance of non-nesting raptors on the Hanford Site and adjacent areas of southcentral Washington (7) to document present land use practices on the Hanford Site and their effects on raptors, (8) to document radionuclide levels in birds of prey on the Hanford Site, and (9) to determine the role of birds of prey in radioecological monitoring.

  7. Proceedings of the 1993 Particle Accelerator Conference Held in Washington, DC on May 17-20, 1993. Volume 4

    Science.gov (United States)

    1994-05-18

    535 (1991). 2680 Sheet-Beam Klystron RF Cavlties" David Yu, DULY Research Inc., Rancho Palos Verdes, CA Perry Wilson, SLAC, Stanfor,4 CA We consider...34, Particles 1. Z. Pams, ’Preliminary Emittaasce Measmurements and and Fields 9 1, Vol. 2, 1073, Ed. David Axen, Douglas Ceknlatinsa of the Lawe Escited...Band Figure 6. R0% Y nornalized emiftance vs. S-Bwud buschermpiue ~ceaoue 1V. Smmar of Rsust The noia gu0n ndeSBn o injector13 aeor moeISwt AREA

  8. How Can Improvements Be Made to the United States Metrorail System (With a Focus on the Washington Metropolitan Area Transit Authority Metrorail System) to Enhance Safety for Its Riders

    Science.gov (United States)

    2016-06-10

    due to special events in the area to include Washington Redskins football , Washington National baseball, and other events held in the Washington, D.C...The technological 15 Ibid. 16 Ibid. 17 Ibid. 17 methods involved using television and video

  9. Prioritization and accelerated remediation of groundwater contamination in the 200 Areas of the Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Wittreich, C.D.; Ford, B.H.

    1993-04-01

    The Hanford Site, operated by the US Department of Energy (DOE), occupies about 1,450 km{sup 2} (560 mi{sup 2}) of the southeastern part of Washington State north of the confluence of the Yakima and Columbia Rivers. The Hanford Site is organized into numerically designated operational areas. The 200 Areas, located near the center of the Hanford Site, encompasses the 200 West, East and North Areas and cover an area of over 40 km{sup 2}. The Hanford Site was originally designed, built, and operated to produce plutonium for nuclear weapons using production reactors and chemical reprocessing plants. Operations in the 200 Areas were mainly related to separation of special nuclear materials from spent nuclear fuel and contain related chemical and fuel processing and waste management facilities. Large quantities of chemical and radioactive waste associated with these processes were often disposed to the environment via infiltration structures such as cribs, ponds, ditches. This has resulted in over 25 chemical and radionuclide groundwater plumes, some of which have reached the Columbia River. An Aggregate Area Management Study program was implemented under the Hanford Federal Facility Agreement and Consent Order to assess source and groundwater contamination and develop a prioritized approach for managing groundwater remediation in the 200 Areas. This included a comprehensive evaluation of existing waste disposal and environmental monitoring data and the conduct of limited field investigations (DOE-RL 1992, 1993). This paper summarizes the results of groundwater portion of AAMS program focusing on high priority contaminant plume distributions and the groundwater plume prioritization process. The objectives of the study were to identify groundwater contaminants of concern, develop a conceptual model, refine groundwater contaminant plume maps, and develop a strategy to expedite the remediation of high priority contaminants through the implementation of interim actions.

  10. Nuclear Science Symposium, 29th, and Symposium on Nuclear Power, 14th, Washington, DC, October 20-22, 1982, Proceedings

    Science.gov (United States)

    Davis, W. D.

    1983-01-01

    High-energy radiation detectors suitable for balloon-borne or space-based radiation event studies are described. The employment of NaI(Tl) scintillator bars for gamma ray detection is outlined, and the development of a fluorescent gated gas-filled scintillation proportional counter is reported. A high throughput nondispersive hard X ray spectrograph with angular resolution for cosmic bursts, transients, and sources has been constructed. Features of a sealed high pressure xenon filled imaging proportional counter with a 30 sq cm sensitive area are explored. Finally, the various radiation effects on electronic circuitry in a space environment are defined, and an MOS dosimeter for assaying the cumulative radiation flux in a spacecraft due to ambient conditions is characterized.

  11. Five years (2000-2004) of post-reconstruction monitoring of freshwater tidal wetlands in the urban Anacostia River, Washington, D.C. USA

    Science.gov (United States)

    Hammerschlag, D.; Krafft, C.

    2006-01-01

    The Anacostia River in Washington, D.C. USA consisted of over 809 hectares (2000 acres) of freshwater tidal wetlands before mandatory dredging removed most of them in the first half of the 20th century. Much of this13 kilometer (8 mile) reach was transferred to the National Park Service (NPS). Planning processes in the 1980's envisioned a restoration (rejuvenation) of some wetlands for habitat, aesthetics, water quality and interpretative purposes. Subsequently, the U.S. Army Corps of Engineers in a cost share agreement with the District of Columbia reconstructed wetlands on NPS lands at Kenilworth - 12.5 hectares (1993), Kingman 27 hectares (2000), a Fringe Marsh - 6.5 hectares (2003) and is currently constructing Heritage Marsh - 2.5 hectares (2005/2006). The USGS Patuxent Wildlife Research Center in conjunction with the University of Maryland Biological Engineering Department was contracted to conduct post-reconstruction monitoring (2000-2004) to document the relative success and progress of the Kingman Marsh reconstruction primarily based on vegetative response but also in conjunction with seed bank and soil characteristics. Results from Kingman were compared to Kenilworth Marsh (reconstructed 7 years prior), Dueling Creek Marsh (last best remaining freshwater tidal wetland bench in the urbanized Anacostia watershed) and Patuxent River Marsh (in a more natural adjacent watershed). Vegetation establishment was initially strong at Kingman, but declined rapidly as measured by cover, richness, diversity, etc. under grazing pressure from resident Canada geese and associated reduction in sediment levels. This decline did not occur at the other wetlands. The decline occurred despite a substantial seed bank that was sustained primarily be water born propagules. Soil development, as true for most juvenile wetlands, was slow with almost no organic matter accumulation. By 2004 only two of 7 planted species remained (mostly Peltandra virginica) at Kingman which did provide

  12. A qualidade de vida de jovens portadores de espinha bífida do Children's National Medical Center – Washington DC

    Directory of Open Access Journals (Sweden)

    Ana Helena Rotta Soares

    2006-09-01

    Full Text Available O presente artigo tem como objetivo explorar a qualidade de vida de jovens portadores de espinha bífida atendidos no Children's National Medical Center em Washington DC. A pesquisa baseia-se em uma perspectiva qualitativa que utiliza como referencial teórico central a "Teoria do estigma" e as discussões conceituais sobre as dimensões de qualidade de vida. Foram entrevistados 15 jovens do serviço acima citado, sendo que 8 deles participaram de um grupo focal construído através das questões levantadas durante entrevistas. Os discursos dos jovens em questão refletem a necessidade de categorias mais englobantes que não remetam a uma pulverização da experiência de vida. Evidenciou-se uma estrutura de desigualdade nas interações entre saudáveis e deficientes, e reproduzida pelos próprios jovens. Os resultados demonstram que o estigma se encontra presente em todas as dimensões da vida dos sujeitos, interferindo na inserção social, construção subjetiva do jovem e sua auto-estima, reforçando o papel do portador de deficiência como uma "não-pessoa". Embora a categoria sexualidade não seja priorizada em outros instrumentos para esta população, o tema se faz presente e central na discussão da experiência da vida dos mesmos.

  13. Improving immunogenicity, efficacy and safety of vaccines through innovation in clinical assay development and trial design: the Phacilitate Vaccine Forum, Washington D.C. 2011.

    Science.gov (United States)

    Moldovan, Ioana R; Tary-Lehmann, Magdalena

    2011-06-01

    The 9th Annual Vaccine Forum organized by Phacilitate in Washington D.C. 2011 brought together 50+ senior level speakers and over 400 participants representing all the key stakeholders concerning vaccines. The main focus of the meeting was to define priorities in the global vaccines sector from funding to manufacturing and evaluation of vaccine efficacy. A special session was devoted to improving immunogenicity, efficacy and safety of vaccines through innovation in clinical assay development and trial design. The current regulatory approach to clinical assay specification, validation and standardization that enable more direct comparisons of efficacy between trials was illustrated by the success in meningococcal vaccine development. The industry approach to validation strategies was exemplified by a new serologic test used on the diagnostic of pneumococcal pneumonia. The application of the Animal Rule to bridge clinical and non-clinical studies in botulism has allowed significant progress in developing one of the first vaccines to seek approval under the FDA Animal Efficacy Rule. An example of pushing the boundaries in the correlation of immunological responses and efficacy points was represented by a recent cell-based influenza vaccine for which the same correlates of protection apply as for the traditional, egg-based flue vaccine. In the field of HIV phase 2b studies are underway, based on promising results obtained with some vaccine candidates. The conclusion of this session was that creativity in vaccine design and evaluation is beneficial and can lead to innovative new vaccine designs as well as to validated assays to assess vaccine efficacy.

  14. The greening of the U.S. Department of Energy Headquarters, Washington, D.C. Second-year status report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-04-22

    The Greening of the Department of Energy Headquarters is a comprehensive, multi-year project designed to identify and implement specific actions DOE can take to save energy and money, improve the comfort and productivity of employees, and benefit the environment. It is part of the Administration`s overall effort to promote greening in all of the nation`s federal buildings. Present Clinton started the Greening of the White House in 1993, and similar efforts have been undertaken by the Department of Defense at the Pentagon, the National Park Service at the Presidio, and now the Department of Energy at the Forrestal and Germantown buildings. The Greening of the Department of Energy Headquarters, An Action Plan for Success (Action Plan), unveiled on April 22, 1996, outlined more than 80 action items for DOE`s Forrestal and Germantown buildings. The action items were designed to increase energy efficiency, improve resource management, improve air quality, reduce water use, reduce paper use, improve landscape management, improve maintenance and operational procedures, increase employee participation, and promote education and outreach. In the two years since the Action Plan was introduced, the Department of Energy has made major progress in implementing specific action items designed to target four major subject areas: (1) Energy Efficiency; (2) Resource Management; (3) Air, Water, Landscape, and (4) Human Factors. This report outlines the status of the recommendations of the Action Plan since they were introduced two years ago.

  15. Geology and hydrology of the 300 Area and vicinity, Hanford Site, South-Central Washington

    Science.gov (United States)

    Gaylord, D. R.; Poeter, E. P.

    1991-10-01

    The following report summarizes the findings of a joint Washington State University (WSU) and Colorado School of Mines (CSM) research team that investigated the geology and hydrogeology of the 300 Area during FY 87-89. The primary goal of this research was to evaluate existing data and identify new and innovative techniques and/or methods necessary to characterize the 300 Area geology and hydrogeology. Site characterization of the 300 Area demands the close integration of geologic and hydrogeologic research to achieve the most meaningful results. Geologic aspects of the research focused on the identification and analysis of both small- (i.e., sedimentary-textural characteristics) and large-scale (i.e., lithofacies and architectural elements) aquifer heterogeneities and on the derivation of fundamental compositional (i.e., mineralogy and geochemistry) data to assist in identification of marker beds. Hydrogeologic aspects of the research focused on identification and refinement of hydraulically significant, three-dimensional aquifer units termed hydrofacies and on preliminary inverse modeling of ground water flow in the 300 Area. Hydrofacies are fundamental units that will aid in site characterization, development of monitoring programs, and design of remedial action. Inverse modeling is used to improve estimates of the values of hydraulic parameters associated with each hydrofacies. The WSU/CSM research team identified two major shortcomings of the geologic and hydrogeologic data base for the 300 Area. First, the quality of geologic data from 300 Area drilling is far below that necessary to characterize either the geology or hydrogeology of the suprabasalt strata. Second, the limited number of field-scale aquifer tests and the veritable lack of hydraulic testing of discrete aquifer intervals greatly limit attempts to accurately identify basic hydraulic parameters such as hydraulic conductivity and/or specific yield.

  16. Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Marcel P. [Washington River Protection Solutions LLC, Richland, WA (United States); Singleton, Kristin M. [Washington River Protection Solutions LLC, Richland, WA (United States); Eberlein, Susan J. [Washington River Protection Solutions LLC, Richland, WA (United States)

    2015-01-07

    A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

  17. Aerial Photography and Imagery, Ortho-Corrected, Washington County, NC true color orhophotography - 1/2 foot resolution over selected areas, Published in 2009, 1:2400 (1in=200ft) scale, Washington County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Aerial Photography and Imagery, Ortho-Corrected dataset current as of 2009. Washington County, NC true color orhophotography - 1/2 foot resolution over selected areas.

  18. Implementation of a Multimodal Mobile System for Point-of-Sale Surveillance: Lessons Learned From Case Studies in Washington, DC, and New York City.

    Science.gov (United States)

    Cantrell, Jennifer; Ganz, Ollie; Ilakkuvan, Vinu; Tacelosky, Michael; Kreslake, Jennifer; Moon-Howard, Joyce; Aidala, Angela; Vallone, Donna; Anesetti-Rothermel, Andrew; Kirchner, Thomas R

    2015-01-01

    In tobacco control and other fields, point-of-sale surveillance of the retail environment is critical for understanding industry marketing of products and informing public health practice. Innovations in mobile technology can improve existing, paper-based surveillance methods, yet few studies describe in detail how to operationalize the use of technology in public health surveillance. The aims of this paper are to share implementation strategies and lessons learned from 2 tobacco, point-of-sale surveillance projects to inform and prepare public health researchers and practitioners to implement new mobile technologies in retail point-of-sale surveillance systems. From 2011 to 2013, 2 point-of-sale surveillance pilot projects were conducted in Washington, DC, and New York, New York, to capture information about the tobacco retail environment and test the feasibility of a multimodal mobile data collection system, which included capabilities for audio or video recording data, electronic photographs, electronic location data, and a centralized back-end server and dashboard. We established a preimplementation field testing process for both projects, which involved a series of rapid and iterative tests to inform decisions and establish protocols around key components of the project. Important components of field testing included choosing a mobile phone that met project criteria, establishing an efficient workflow and accessible user interfaces for each component of the system, training and providing technical support to fieldworkers, and developing processes to integrate data from multiple sources into back-end systems that can be utilized in real-time. A well-planned implementation process is critical for successful use and performance of multimodal mobile surveillance systems. Guidelines for implementation include (1) the need to establish and allow time for an iterative testing framework for resolving technical and logistical challenges; (2) developing a streamlined

  19. Willingness of community-recruited men who have sex with men in Washington, DC to use long-acting injectable HIV pre-exposure prophylaxis.

    Directory of Open Access Journals (Sweden)

    Matthew E Levy

    Full Text Available Clinical trials are currently investigating the safety and efficacy of long-acting injectable (LAI agents as HIV pre-exposure prophylaxis (PrEP. Using National HIV Behavioral Surveillance data, we assessed the self-reported willingness of men who have sex with men (MSM to use LAI PrEP and their preference for LAI versus daily oral PrEP.In 2014, venue-based sampling was used to recruit MSM aged ≥18 years in Washington, DC. Participants completed an interviewer-administered survey followed by voluntary HIV testing. This analysis included MSM who self-reported negative/unknown HIV status at study entry. Correlates of being "very likely" to use LAI PrEP and preferring it to daily oral PrEP were identified using multivariable logistic regression.Of 314 participants who self-reported negative/unknown HIV status, 50% were <30 years old, 41% were non-Hispanic Black, 37% were non-Hispanic White, and 14% were Hispanic. If LAI PrEP were offered for free or covered by health insurance, 62% were very likely, 25% were somewhat likely, and 12% were unlikely to use it. Regarding preferred PrEP modality, 67% chose LAI PrEP, 24% chose oral PrEP, and 9% chose neither. Correlates of being very likely versus somewhat likely/unlikely to use LAI PrEP included age <30 years (aOR 1.64; 95% CI 1.00-2.68, reporting ≥6 (vs. 1 sex partners in the last year (aOR 2.60; 95% CI 1.22-5.53, previous oral PrEP use (aOR 3.67; 95% CI 1.20-11.24, and being newly identified as HIV-infected during study testing (aOR 4.83; 95% CI 1.03-22.67. Black (vs. White men (aOR 0.48; 95% CI 0.24-0.96 and men with an income of <$20,000 (vs. ≥$75,000; aOR 0.37; 95% CI 0.15-0.93 were less likely to prefer LAI to oral PrEP.If LAI PrEP were found to be efficacious, its addition to the HIV prevention toolkit could facilitate more complete PrEP coverage among MSM at risk for HIV.

  20. 10 m bathymetric contours for the Southwest Washington Study area (BATHY)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Two 21-day field operations were conducted in 1997 and 1998 in the estuaries and on the inner continental shelf off the northern Oregon and southern Washington...

  1. A New Control Structure for Multi-Terminal dc Grids to Damp Inter-Area Oscillations

    DEFF Research Database (Denmark)

    Eriksson, Robert

    2014-01-01

    This article analyzes the control structure of the multi-terminal dc (MTDC) system to damp ac system interarea oscillations through active power modulation. A new control structure is presented that maximizes the relative controllability without the need for communication among the dc terminals....... In point-to-point high voltage dc (HVDC) transmission, the active power modulation of the two terminals occurs in opposite directions. In this case the control direction is given and only needs to be phase compensated to align for maximal damping. In the case of MTDC systems the control direction...

  2. Three-dimensional ground-motion simulations of earthquakes for the Hanford area, Washington

    Science.gov (United States)

    Frankel, Arthur; Thorne, Paul; Rohay, Alan

    2014-01-01

    This report describes the results of ground-motion simulations of earthquakes using three-dimensional (3D) and one-dimensional (1D) crustal models conducted for the probabilistic seismic hazard assessment (PSHA) of the Hanford facility, Washington, under the Senior Seismic Hazard Analysis Committee (SSHAC) guidelines. The first portion of this report demonstrates that the 3D seismic velocity model for the area produces synthetic seismograms with characteristics (spectral response values, duration) that better match those of the observed recordings of local earthquakes, compared to a 1D model with horizontal layers. The second part of the report compares the response spectra of synthetics from 3D and 1D models for moment magnitude (M) 6.6–6.8 earthquakes on three nearby faults and for a dipping plane wave source meant to approximate regional S-waves from a Cascadia great earthquake. The 1D models are specific to each site used for the PSHA. The use of the 3D model produces spectral response accelerations at periods of 0.5–2.0 seconds as much as a factor of 4.5 greater than those from the 1D models for the crustal fault sources. The spectral accelerations of the 3D synthetics for the Cascadia plane-wave source are as much as a factor of 9 greater than those from the 1D models. The differences between the spectral accelerations for the 3D and 1D models are most pronounced for sites with thicker supra-basalt sediments and for stations with earthquakes on the Rattlesnake Hills fault and for the Cascadia plane-wave source.

  3. Bibliography of the geology of the Columbia Basin and surrounding areas of Washington

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, G.B.; Rigby, J.G.

    1979-07-01

    In the fall of 1977, the Washington State Department of Natural Resources, Division of Geology and Earth Resources (WDGER), entered into a contract with the US Department of Energy, administered by Rockwell Hanford Operations (Rockwell) in Richland, Washington, as a principal contributor to a geologic study of feasibility of storing radioactive waste within Columbia River basalt. WDGER's responsibility was the production of this bibliography and a reconnaissance geologic map of the sediments overlying the Columbia River Basalt Group in the State of Washington. This bibliography is a compilation of all known published, unpublished, and open-file references dealing with geology and geophysics of the Columbia Basin of eastern Washington. The citations were obtained primarily from the WDGER and Washington State libraries; the Geo-Ref bibliographic system was also utilized. Because the WDGER portion of the study included preparation of a reconnaissance geologic map of surficial deposits in the Columbia Basin, available references dealing with this subject have been annotated. Many abstracts in the annotated section are quotations and have been copied directly from their respective publications.

  4. The impacts of aerosol loading, composition, and water uptake on aerosol extinction variability in the Baltimore-Washington, D.C. region

    Science.gov (United States)

    Beyersdorf, A. J.; Ziemba, L. D.; Chen, G.; Corr, C. A.; Crawford, J. H.; Diskin, G. S.; Moore, R. H.; Thornhill, K. L.; Winstead, E. L.; Anderson, B. E.

    2016-01-01

    In order to utilize satellite-based aerosol measurements for the determination of air quality, the relationship between aerosol optical properties (wavelength-dependent, column-integrated extinction measured by satellites) and mass measurements of aerosol loading (PM2.5 used for air quality monitoring) must be understood. This connection varies with many factors including those specific to the aerosol type - such as composition, size, and hygroscopicity - and to the surrounding atmosphere, such as temperature, relative humidity (RH), and altitude, all of which can vary spatially and temporally. During the DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) project, extensive in situ atmospheric profiling in the Baltimore, MD-Washington, D.C. region was performed during 14 flights in July 2011. Identical flight plans and profile locations throughout the project provide meaningful statistics for determining the variability in and correlations between aerosol loading, composition, optical properties, and meteorological conditions. Measured water-soluble aerosol mass was composed primarily of ammonium sulfate (campaign average of 32 %) and organics (57 %). A distinct difference in composition was observed, with high-loading days having a proportionally larger percentage of sulfate due to transport from the Ohio River Valley. This composition shift caused a change in the aerosol water-uptake potential (hygroscopicity) such that higher relative contributions of inorganics increased the bulk aerosol hygroscopicity. These days also tended to have higher relative humidity, causing an increase in the water content of the aerosol. Conversely, low-aerosol-loading days had lower sulfate and higher black carbon contributions, causing lower single-scattering albedos (SSAs). The average black carbon concentrations were 240 ng m-3 in the lowest 1 km, decreasing to 35 ng m-3 in the free troposphere (above

  5. The impacts of aerosol loading, composition, and water uptake on aerosol extinction variability in the Baltimore–Washington, D.C. region

    Directory of Open Access Journals (Sweden)

    A. J. Beyersdorf

    2016-01-01

    Full Text Available In order to utilize satellite-based aerosol measurements for the determination of air quality, the relationship between aerosol optical properties (wavelength-dependent, column-integrated extinction measured by satellites and mass measurements of aerosol loading (PM2.5 used for air quality monitoring must be understood. This connection varies with many factors including those specific to the aerosol type – such as composition, size, and hygroscopicity – and to the surrounding atmosphere, such as temperature, relative humidity (RH, and altitude, all of which can vary spatially and temporally. During the DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality project, extensive in situ atmospheric profiling in the Baltimore, MD–Washington, D.C. region was performed during 14 flights in July 2011. Identical flight plans and profile locations throughout the project provide meaningful statistics for determining the variability in and correlations between aerosol loading, composition, optical properties, and meteorological conditions. Measured water-soluble aerosol mass was composed primarily of ammonium sulfate (campaign average of 32 % and organics (57 %. A distinct difference in composition was observed, with high-loading days having a proportionally larger percentage of sulfate due to transport from the Ohio River Valley. This composition shift caused a change in the aerosol water-uptake potential (hygroscopicity such that higher relative contributions of inorganics increased the bulk aerosol hygroscopicity. These days also tended to have higher relative humidity, causing an increase in the water content of the aerosol. Conversely, low-aerosol-loading days had lower sulfate and higher black carbon contributions, causing lower single-scattering albedos (SSAs. The average black carbon concentrations were 240 ng m−3 in the lowest 1 km, decreasing to 35

  6. 100/300 Area Aquifer Tube Task: Annual Sampling for Fiscal Year 2006, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Robert E.; Hartman, Mary J.; Raidl, Robert F.; Borghese, Jane V.

    2005-11-01

    This letter report has been prepared to provide the U.S. Department of Energy, U.S. Environmental Protection Agency, Washington State Department of Ecology, and Hanford Site contractors with logistical information pertaining to the use of certain environmental monitoring sites. Although the distribution is not limited, It is not intended for general distribution beyond that audience.

  7. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Puget Sound and Strait of Juan de Fuca, Washington: MGT (Management Area Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains polygons that represent the following sensitive human-use management areas in Puget Sound and the Strait of Juan de Fuca, Washington:...

  8. EFH Conservation Areas off Washington, Oregon, and California for NMFS' Final Rule Implementing Amendment 19 to the Pacific Coast Groundfish Fishery Management Plan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data depict Essential Fish Habitat (EFH) conservation areas off Washington, Oregon, and California. The coordinate locations are from NMFS' Final Rule to...

  9. Development of bus-stop time models in dense urban areas : a case study in Washington DC.

    Science.gov (United States)

    2015-08-01

    Bus transit reliability depends on several factors including the route of travel, traffic conditions, time of day, and conditions at : the bus stops along the route. The number of passengers alighting or boarding, fare payment method, dwell time (DT)...

  10. Abundance of Apple Maggot, Rhagoletis pomonella, Across Different Areas in Central Washington, with Special Reference to Black-Fruited Hawthorns

    Science.gov (United States)

    Yee, Wee L.; Klaus, Michael W.; Cha, Dong H.; Linn, Charles E.; Goughnour, Robert B.

    2012-01-01

    The apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), infests non-commercial apple (Malus domestica (Borkh.) Borkh.) and native black-fruited hawthorns (mostly Crataegus douglasii Lindl.) in central Washington, but little has been published on the abundance of the fly in this region. In this paper, the abundance of R. pomonella across different sites near apple-growing areas in central Washington is documented in order to assess the threat of the fly to commercial apple orchards. The fly was first detected on traps in Klickitat, Yakima, and Kittitas Counties in 1981, 1995, and 1997, respectively. From 1981–2010 in Kittitas and Yakima Counties, only 0 to 4.7% of traps on apple, crabapple, and hawthorn trees were positive for flies, whereas in Klickitat County, located farther from commercial apple orchards, 0 to 41.9% of traps were positive. In 2008, in Yakima County and Goldendale in Klickitat County, 7.8% of black-fruited hawthorn trees were infested, with 0 to 0.00054 larvae per fruit. In 2010, in Kittitas and Yakima Counties and Goldendale in Klickitat County, 25.0% of C. douglasii trees were infested, with 0.00042 to 0.00248 larvae per fruit. In 2010, in a remote forested area of Klickitat County far from commercial apple orchards, 94.7% of C. douglasii trees were infested, with 0.20813 larvae per fruit. Overall results suggest R. pomonella is unlikely to develop high populations rapidly near major commercial apple-growing areas in central Washington, including in black-fruited hawthorns, increasing chances it can be kept out of commercial orchards. PMID:23451979

  11. Abundance of apple maggot, Rhagoletis pomonella, across different areas in central Washington, with special reference to black-fruited hawthorns.

    Science.gov (United States)

    Yee, Wee L; Klaus, Michael W; Cha, Dong H; Linn, Charles E; Goughnour, Robert B; Feder, Jeffrey L

    2012-01-01

    The apple maggot fly, Rhagoletis pomonella (Walsh) (Diptera: Tephritidae), infests non-commercial apple (Malus domestica (Borkh.) Borkh.) and native black-fruited hawthorns (mostly Crataegus douglasii Lindl.) in central Washington, but little has been published on the abundance of the fly in this region. In this paper, the abundance of R. pomonella across different sites near apple-growing areas in central Washington is documented in order to assess the threat of the fly to commercial apple orchards. The fly was first detected on traps in Klickitat, Yakima, and Kittitas Counties in 1981, 1995, and 1997, respectively. From 1981-2010 in Kittitas and Yakima Counties, only 0 to 4.7% of traps on apple, crabapple, and hawthorn trees were positive for flies, whereas in Klickitat County, located farther from commercial apple orchards, 0 to 41.9% of traps were positive. In 2008, in Yakima County and Goldendale in Klickitat County, 7.8% of black-fruited hawthorn trees were infested, with 0 to 0.00054 larvae per fruit. In 2010, in Kittitas and Yakima Counties and Goldendale in Klickitat County, 25.0% of C. douglasii trees were infested, with 0.00042 to 0.00248 larvae per fruit. In 2010, in a remote forested area of Klickitat County far from commercial apple orchards, 94.7% of C. douglasii trees were infested, with 0.20813 larvae per fruit. Overall results suggest R. pomonella is unlikely to develop high populations rapidly near major commercial apple-growing areas in central Washington, including in black-fruited hawthorns, increasing chances it can be kept out of commercial orchards.

  12. Issues of scale, location and geologic terrain related to Salt Lake City and Baltimore-Washington metropolitan areas

    Science.gov (United States)

    Cleaves, E.T.; Godfrey, A.E.; ,

    2004-01-01

    Planning and development of expanding metropolitan regions require consideration of earth science issues related to issues involving scale, space (location), geologic terrain and physiographic units, and information transfer. This paper explores these matters with examples from the Salt Lake City, Utah area and Mid-Atlantic region of Baltimore-Washington that include water supply and natural hazards (earthquakes, landslides, and sinkholes.) Information transfer methods using physiographic units at national, regional, local and site scales serve to communicate relevant geologic constraint and natural resource information.

  13. Three approaches to time valuation in recreation demand: a study of the Snake River recreation area in eastern Washington.

    Science.gov (United States)

    McKean, John R; Johnson, Donn; Taylor, R G

    2012-12-15

    Three travel cost models are used to estimate non-fishing recreation demand at the Snake River reservoirs recreation area in eastern Washington. The opportunity cost of time is specified in the "traditional" and McConnell-Strand models as a fraction of the exogenous market wage rate and in the two-step decision model as a function of socioeconomic attributes of the recreationists. Benefits per person per trip were $90, $35, and $46 respectively, for the three models. Boaters visit the site more than three times as often as non-boaters resulting in higher annual benefits for boaters. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. George Washington: A Grounded Leader

    Science.gov (United States)

    2011-04-08

    Highway, Suite 1204·, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188) Washington, DC......a broad array of experiences, enabled him to become a leader who profoundly affected those around him. George Washington reflected a man of the

  15. Nota biobibliográfica + poética + creaciones («Campo de girasoles», «Hierápolis I», «La diosa fortuna», «One life», «Acción por la paz (Washington DC 2012» y «Encruzcijada» + cuestionario (Victoria Pineda

    Directory of Open Access Journals (Sweden)

    Carmen Peralto

    2014-03-01

    Full Text Available Nota biobibliográfica + poética + creaciones («Campo de girasoles», «Hierápolis I», «La diosa fortuna», «One life», «Acción por la paz (Washington DC 2012» y «Encruzcijada» + cuestionario (Victoria Pineda

  16. Proceedings of the American Psychological Association for the Legislative Year 2006: Minutes of the Annual Meeting of the Council of Representatives, February 17-19, 2006, Washington, DC; and August 17 and 21, 2006, New Orleans, LA; and Minutes of the February, June, August, and December 2006 Meetings of the Board of Directors

    Science.gov (United States)

    Paige, Ruth Ullmann

    2007-01-01

    Minutes of the Annual Meeting of the Council of Representatives (February 17-19, 2006, Washington, DC; and August 17 and 21, 2006, New Orleans, LA) and of the 2006 meetings of the Board of Directors (February, June, August, and December) are provided. These minutes are the official record of the actions of the American Psychological Association…

  17. All Prime Contract Awards by State or Country, Place, and Contractor, FY 88. Part 5. (Air Force Academy, Colorado-Washington, DC).

    Science.gov (United States)

    1988-01-01

    Security Classification) All Prime Contract Awards by State or Countr,, Placer and Contractol.) FY 88- Part 5, (Air Force Academy, Colorado-Washington...N I wo- I -~ 0 4’DN mqO O01Oj0ro) (01N -c’ 0 4𔃺oo (1V(DWW CY w I I01- I -4 qr NO0-4M-M-4( N -4 sJ UflI w0P-- a -4 .4 aMor - IC c CC C cC Mor- 1o 0 0 0

  18. Revised Hydrogeology for the Suprabasalt Aquifer System, 200-West Area and Vicinity, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Bruce A.; Bjornstad, Bruce N.; Schalla, Ronald; Webber, William D.

    2002-05-14

    The primary objective of this study was to refine the conceptual groundwater flow model for the 200-West Area and vicinity. This is the second of two reports that combine to cover the 200 Area Plateau, an area that holds the largest inventory of radionuclide and chemical waste on the Hanford Site.

  19. Modeling the Mental Health Workforce in Washington State: Using State Licensing Data to Examine Provider Supply in Rural and Urban Areas

    Science.gov (United States)

    Baldwin, Laura-Mae; Patanian, Miriam M.; Larson, Eric H.; Lishner, Denise M.; Mauksch, Larry B.; Katon, Wayne J.; Walker, Edward; Hart, L. Gary

    2006-01-01

    Context: Ensuring an adequate mental health provider supply in rural and urban areas requires accessible methods of identifying provider types, practice locations, and practice productivity. Purpose: To identify mental health shortage areas using existing licensing and survey data. Methods: The 1998-1999 Washington State Department of Health files…

  20. Prime Contract Awards by State or Country, Place and Contractor. Part 5 (Long Beach-Lakewood, California - Washington, DC), FY1991

    Science.gov (United States)

    1991-01-01

    02>2 66 00 00 000> 00C C w 0 C 00 00 C0 0 0 6 (D If v. r- 0 24 6 -t-FP-- or- orr -- u r- -- v P.- ur or- o r- or uI- o r- or-, o6 0 ui I: &-02 6 0 00...D0C 0 I- o4 o-o0 C) o o 11a2%1I0MID 11W I0 -OO O C0 NIPC NI I C> L-00 D< 1 󈧄 100 4OO N , 0 O 0 N ) o0) C D DC 0) C. II L Moo 11 s- -.4 S--L 4- -4 -4

  1. Fiscal year 1991 report on archaeological surveys of the 100 Areas, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Chatters, J.C.; Gard, H.A.; Minthorn, P.E.

    1992-09-01

    In compliance with Section 106 of the National Historic Preservation Act (NHPA), and at the request of Westinghouse Hanford Company, the Hanford Cultured Resources Laboratory (HCRL) conducted an archaeological survey during FY 1991 of the 100-Area reactor compounds on the US Department of Energy's Hanford Site. This survey was conducted as part of a comprehensive resources review of 100-Area Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) operable units in support of CERCLA characterization activities. The work included a lite and records review and pedestrian survey of the project area following procedures set forth in the Hanford Cultural Resources Management Plan.

  2. Fiscal year 1991 report on archaeological surveys of the 100 Areas, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Chatters, J.C.; Gard, H.A.; Minthorn, P.E.

    1992-09-01

    In compliance with Section 106 of the National Historic Preservation Act (NHPA), and at the request of Westinghouse Hanford Company, the Hanford Cultured Resources Laboratory (HCRL) conducted an archaeological survey during FY 1991 of the 100-Area reactor compounds on the US Department of Energy`s Hanford Site. This survey was conducted as part of a comprehensive resources review of 100-Area Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) operable units in support of CERCLA characterization activities. The work included a lite and records review and pedestrian survey of the project area following procedures set forth in the Hanford Cultural Resources Management Plan.

  3. The observed response of ozone production to the policy-driven decrease of NOx and CO emissions in the Baltimore/Washington area

    Science.gov (United States)

    Roberts, S. J.; Hosley, K.; Ren, X.; Wolfe, G.; Dickerson, R. R.; Salawitch, R. J.

    2015-12-01

    The nonlinearity of ozone production has important policy implications as cities continue to decrease NOx, CO, and other important ozone precursors. Observations in the Baltimore/Washington area from 1970 through 2014 demonstrate reductions in NOx and CO emissions due to policy implementation leading to dramatic improvement in air quality. We will analyze the response of the reactivity of ozone, NOx, and VOC to these emission reductions in the Baltimore/Washington area using the University of Washington Chemical Model (UWCMv2.2). This model allows us to evaluate this response using multiple gas-phase chemical mechanisms. With this model, we will also compare and contrast the response of modeled ozone to reduced NOx and CO concentrations across multiple chemical mechanisms.

  4. Fiscal year 1992 report on archaeological surveys of the 100 Areas, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Wright, M.K.

    1993-09-01

    During FY 1992, the Hanford Cultural Resources Laboratory (HCRL) conducted a field survey of the 100-HR-3 Operable Unit (600 Area) and tested three sites near the 100 Area reactor compounds on the US Department of Energy`s Hanford Site at the request of Westinghouse Hanford Company. These efforts were conducted in compliance with Section 106 of the National Historic Preservation Act (NHPA) and are part of a cultural resources review of 100 Area Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) operable units in support of CERCLA characterization studies.The results of the FY 1992 survey and test excavation efforts are discussed in this report. 518 ha in the 100-HR-3 Operable Unit and conducted test excavations at three prehistoric sites near the 100-F and 100-K reactors to determine their eligibility for listing on the National Register of Historic Places.

  5. 78 FR 4804 - Revision to the Washington State Implementation Plan; Tacoma-Pierce County Nonattainment Area

    Science.gov (United States)

    2013-01-23

    ... Ecology (Ecology) dated November 28, 2012. This SIP revision consists of two elements proposed for EPA... (CAA) requirements related to the Tacoma-Pierce County nonattainment area for the 2006 fine particulate... updated rules submitted by Ecology on behalf of the Puget Sound Clean Air Agency (PSCAA), contained in...

  6. Revised Hydrogeology for the Suprabasalt Aquifer System, 200-East Area and Vicinity, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Bruce A.; Bjornstad, Bruce N.; Schalla, Ronald; Webber, William D.

    2000-04-20

    This study supports the Hanford Groundwater/Vadose integration project objectives to better understand the risk of groundwater contamination and potential risk to the public via groundwater flow paths. The primary objective of this study was to refine the conceptual groundwater flow model for the 200-East Area and vicinity.

  7. Uranium Contamination in the Subsurface Beneath the 300 Area, Hanford Site, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Robert E.; Rockhold, Mark L.; Serne, R. Jeffrey; Thorne, Paul D.; Williams, Mark D.

    2008-02-29

    This report provides a description of uranium contamination in the subsurface at the Hanford Site's 300 Area. The principal focus is a persistence plume in groundwater, which has not attenuated as predicted by earlier remedial investigations. Included in the report are chapters on current conditions, hydrogeologic framework, groundwater flow modeling, and geochemical considerations. The report is intended to describe what is known or inferred about the uranium contamination for the purpose of making remedial action decisions.

  8. Metropolitan Washington Area Water Supply Study. Appendix A. Background Information & Problem Identification.

    Science.gov (United States)

    1983-09-01

    area: the Patuxent, Patapsco, Magothy, and the Aquia Greensand Formations. All of these important water- bearing formations outcrop in the MWA and have...of a Potomac River intake and water filtration plant, Leesburg now has the capability of not only providing water f or its own use but also f or the...or approve subdivision plans unless they are in accordance with the county plans. The WSSC operates two large water filtration plants to supply its

  9. Geohydrology and numerical model analysis of ground-water flow in the Pullman-Moscow area, Washington and Idaho

    Science.gov (United States)

    Lum, W. E.; Smoot, James L.; Ralston, Dale R.

    1990-01-01

    The geohydrology of the Pullman, Washington-Moscow, Idaho area was investigated by mapping geohydrologic units, determining the distribution of hydraulic head in each unit, and determining some of the components of the water budget. This information was used to construct a three- dimensional groundwater-flow model that incorporates three layers--a surficial loess layer, a Wanapum Basalt layer, and a Grande Ronde Basalt layer. The model was used to assess the effects of changes in the rate of withdrawal of groundwater on the water levels in the geohydrologic units and on streamflow in the area. Recharge to the groundwater system was calculated independent of the model. It was determined that current farming practices use soil moisture more effectively than did natural vegetation, and these practices have reduced groundwater recharge by nearly 10%. The three-dimensional model was calibrated using the time- averaged method for the period 1974-85, and was evaluated by simulating historical pumpage rate changes (1890-1985) and comparing calculated with observed water-level changes. Model results indicate that groundwater levels would stop declining if pumpage were stabilized at a constant level. Levels will continue to decline into the foreseeable future, however, as long as groundwater pumpage continues to increase. The source of the additional simulated pumpage is streamflow depletion near pumping locations. (USGS)

  10. Taste and smell function in chronic disease: a review of clinical and biochemical evaluations of taste and smell dysfunction in over 5000 patients at The Taste and Smell Clinic in Washington, DC.

    Science.gov (United States)

    Henkin, Robert I; Levy, Lucien M; Fordyce, April

    2013-01-01

    To describe systematic methods developed over 40 years among over 5000 patients at The Taste and Smell Clinic in Washington, DC to evaluate taste and smell dysfunction. A tripartite methodology was developed. First, methods to determine clinical pathology underlying the multiple disease processes responsible for taste and smell dysfunction were developed. Second, methods to determine biochemical parameters responsible for these pathologies were developed. Third, methods to implement these techniques were developed to form a unified basis upon which treatment strategies can be developed to treat these patients. Studies were performed in 5183 patients. Taste loss was present in 62% of patients, smell loss in 87%. Most patients with taste loss (52%) exhibited Type II hypogeusia; most patients with smell loss (56%) exhibited Type II hyposmia. Sensory distortions were present in 60%. Four common diagnostic entities were found: post influenza-type hyposmia and hypogeusia (27% of patients), idiopathic causes (16%), allergic rhinitis (15%) and post head injury (14%). Regardless of clinical diagnosis the major biochemical abnormality found in most patients (~70%) was diminished parotid salivary and nasal mucus secretion of cAMP and cGMP. Taste and smell dysfunctions are common clinical problems associated with chronic disease processes. These symptoms require a systematic, integrated approach to understand their multiple and complex components. The approach presented here can and has led to effective treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Shackling the shoulders of giants. A report on excerpts from the National Academies' Symposium on the Role of Scientific and Technical Data and Information in the Public Domain, Washington, DC, September 5-6, 2002.

    Science.gov (United States)

    Gardenier, John S

    2003-07-01

    This paper informally summarizes a two-day symposium held at the U.S. National Academy of Sciences in Washington, D.C., September 5-6, 2002. The issue was to what extent the progress of science and societal capacity for continued technological innovation are threatened by excessive protection of intellectual property. Excessive protection creates disadvantages not only for scientists and inventors but also for educators/students and for librarians/clientele. Speakers from a variety of disciplines and institutions agreed unanimously that scientific and technological progress is, indeed, under serious threat. Various opinions were expressed about the degree of threat, currently and prospectively, as well as what counter-measures are best suited to resist undue restrictions on creative uses of scientific and technical data and information. This summary is based entirely on the author's notes from the symposium, and the commentary offered is his alone. My apologies to the speakers if this paper does not accurately reflect the primary intent of their presentations. The "Suggested Readings" offered at the end are not specific to the speakers' statements but rather are offered as a general resource to aid further research. The definitive record of the symposium is planned to be available from the National Academies Press as a Proceedings publication in the summer of 2003.

  12. Groundwater contaminant plume maps and volumes, 100-K and 100-N Areas, Hanford Site, Washington

    Science.gov (United States)

    Johnson, Kenneth H.

    2016-09-27

    This study provides an independent estimate of the areal and volumetric extent of groundwater contaminant plumes which are affected by waste disposal in the 100-K and 100-N Areas (study area) along the Columbia River Corridor of the Hanford Site. The Hanford Natural Resource Trustee Council requested that the U.S. Geological Survey perform this interpolation to assess the accuracy of delineations previously conducted by the U.S. Department of Energy and its contractors, in order to assure that the Natural Resource Damage Assessment could rely on these analyses. This study is based on previously existing chemical (or radionuclide) sampling and analysis data downloaded from publicly available Hanford Site Internet sources, geostatistically selected and interpreted as representative of current (from 2009 through part of 2012) but average conditions for groundwater contamination in the study area. The study is limited in scope to five contaminants—hexavalent chromium, tritium, nitrate, strontium-90, and carbon-14, all detected at concentrations greater than regulatory limits in the past.All recent analytical concentrations (or activities) for each contaminant, adjusted for radioactive decay, non-detections, and co-located wells, were converted to log-normal distributions and these transformed values were averaged for each well location. The log-normally linearized well averages were spatially interpolated on a 50 × 50-meter (m) grid extending across the combined 100-N and 100-K Areas study area but limited to avoid unrepresentative extrapolation, using the minimum curvature geostatistical interpolation method provided by SURFER®data analysis software. Plume extents were interpreted by interpolating the log-normally transformed data, again using SURFER®, along lines of equal contaminant concentration at an appropriate established regulatory concentration . Total areas for each plume were calculated as an indicator of relative environmental damage. These plume

  13. Bathymetric map and area/capacity table for Castle Lake, Washington

    Science.gov (United States)

    Mosbrucker, Adam R.; Spicer, Kurt R.

    2017-11-14

    The May 18, 1980, eruption of Mount St. Helens produced a 2.5-cubic-kilometer debris avalanche that dammed South Fork Castle Creek, causing Castle Lake to form behind a 20-meter-tall blockage. Risk of a catastrophic breach of the newly impounded lake led to outlet channel stabilization work, aggressive monitoring programs, mapping efforts, and blockage stability studies. Despite relatively large uncertainty, early mapping efforts adequately supported several lake breakout models, but have limited applicability to current lake monitoring and hazard assessment. Here, we present the results of a bathymetric survey conducted in August 2012 with the purpose of (1) verifying previous volume estimates, (2) computing an area/capacity table, and (3) producing a bathymetric map. Our survey found seasonal lake volume ranges between 21.0 and 22.6 million cubic meters with a fundamental vertical accuracy representing 0.88 million cubic meters. Lake surface area ranges between 1.13 and 1.16 square kilometers. Relationships developed by our results allow the computation of lake volume from near real-time lake elevation measurements or from remotely sensed imagery.

  14. Asbestos-cement panels test report, 100K Area, Hanford, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Moustafa, S.E. [Wiss, Janney, Elstner and Associates, Inc., Seattle, WA (United States)

    1993-12-01

    The 105KE/105KW reactor facilities were constructed in the mid-1950s. The 105KE/105KW fuel-basin roof panels are in a radiation controlled area where there is smearable contamination. The roof panels in all of the inspected areas were constructed from corrugated asbestos-cement (A/C) panels. The corrugated A/C roof panels exhibit common signs of aging including cracking, chipping, spalling, or a combination of these processes. Westinghouse Hanford Company (WHC) has engaged Wiss, Janney, Elstner Associates, Inc. (WJE) to perform laboratory and field tests on A/C roof panels of the 105KW building and also to make recommendations for panel replacement, maintenance, or upgrade that will maintain the structural integrity of the roof panels for an additional 20 years of service. This report contains the results of laboratory and in-situ testing performed by WJE. A Roof Proof Load Test Plan was prepared for WJE and approved by WHC. Conclusions and recommendations based on test results are presented for the 190-KE wall panels and 105KW roof panels.

  15. Baseline Risk Assessment Supporting Closure at Waste Management Area C at the Hanford Site Washington

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, Kristin M. [Washington River Protection Solutions LLC, Richland, WA (United States)

    2015-01-07

    The Office of River Protection under the U.S. Department of Energy is pursuing closure of the Single-Shell Tank (SST) Waste Management Area (WMA) C under the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO). A baseline risk assessment (BRA) of current conditions is based on available characterization data and information collected at WMA C. The baseline risk assessment is being developed as a part of a Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI)/Corrective Measures Study (CMS) at WMA C that is mandatory under Comprehensive Environmental Response, Compensation, and Liability Act and RCRA corrective action. The RFI/CMS is needed to identify and evaluate the hazardous chemical and radiological contamination in the vadose zone from past releases of waste from WMA C. WMA C will be under Federal ownership and control for the foreseeable future, and managed as an industrial area with restricted access and various institutional controls. The exposure scenarios evaluated under these conditions include Model Toxics Control Act (MTCA) Method C, industrial worker, maintenance and surveillance worker, construction worker, and trespasser scenarios. The BRA evaluates several unrestricted land use scenarios (residential all-pathway, MTCA Method B, and Tribal) to provide additional information for risk management. Analytical results from 13 shallow zone (0 to 15 ft. below ground surface) sampling locations were collected to evaluate human health impacts at WMA C. In addition, soil analytical data were screened against background concentrations and ecological soil screening levels to determine if soil concentrations have the potential to adversely affect ecological receptors. Analytical data from 12 groundwater monitoring wells were evaluated between 2004 and 2013. A screening of groundwater monitoring data against background concentrations and Federal maximum concentration levels was used to determine vadose zone

  16. Ritzville 1/sup 0/ x 2/sup 0/ NTMS area, Washington: data report

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, C.B.

    1980-07-01

    This data report presents results of ground water and stream/surface sediment reconnaissance in the National Topographic Map Series (NTMS) Ritzville 1/sup 0/ x 2/sup 0/ quadrangle. Surface samples (sediment) were collected from 1063 sites. The target sampling density was one site per 20 square kilometers (eight square miles). Dry conditions contributed to the relatively small number (109) of surface water samples collected. Ground water samples were collected at 830 sites. Neutron activation analysis (NAA) results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Statistical summaries of data and a brief description of results are given. A generalized geologic map and a summary of the geology of the area are included. Data from ground water sites include: (1) water chemistry measurements (pH, conductivity, and alkalinity); (2) physical measurements where applicable (water temperature, well description, and scintillometer reading); and (3) elemental analyses (U, Al, Br, Cl, Dy, F, He, Mg, Mn, Na, and V). Data from sediment sites include: (1) stream water chemistry measurements where applicable (pH, conductivity, and alkalinity); and (2) elemental analyses for sediment samples (U, Th, Hf, Al,Ce, Dy, Eu, Fe, La, Lu, Mn, Sc, Sm, Na, Ti, V, and Yb). Sample site descriptors (stream characteristics, vegetation, etc.) are also tabulatd. Areal distribution maps, histograms, and cumulative frequency plots for most elements; U/Th, U/Hf, and Th/La ratios; and scintillometer readings for sediment samples are included on the microfiche.

  17. Coupling SLEUTH model and population projection to simulate urban growth of the Baltimore-Washington metropolitan area

    Science.gov (United States)

    Shao, Y.; Zhao, S.

    2015-12-01

    This study used two modelling approaches to predict future urban landscapes for the Baltimore-Washington metropolitan area. In the first approach, we implemented traditional SLEUTH urban simulation model by using publicly available and locally-developed land cover and transportation data. Historical land cover data from 1992, 2001, 2006, and 2011 were used to calibrate the SLEUTH model and predict urban growth from 2011 to 2070. The SLEUTH model achieved 94.8% overall accuracy for validation year 2014. For the second modelling approach, we used a future population projection for 2050, aided by a strong population-imperviousness statistical relationship (R2 ~ 0.95), to predict impervious surface density for each county. These population-predicted impervious surface density values were compared to SLEUTH model output, at the county spatial scale. R2 of 0.84 suggested general agreement of overall pattern, although SLEUTH generated higher impervious surface density values for 36 out of 40 counties. For population-predicted impervious surface density, we further developed a lookup table approach to integrate SLEUTH output and generated a spatially explicit urban map for 2050. This lookup table approach has high potential to integrate population-predicted and SLEUTH-predicted urban landscape, especially when future population can be predicted with reasonable accuracy.

  18. Proceedings of the SERI Biomass Program Principal Investigators' Review Meeting: Aquatic Species Program Reports; 23-25 June 1982, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    1982-12-01

    The Aquatic Species Program (ASP) is concerned with how plant biomass that naturally occurs in wetland or submerged areas is utilized. Processes are being developed in this program to make use of those aquatic species, capitalizing on their inherent capacity for rapid growth as well as on their extraordinary chemical compositions.

  19. Installation Assessment of Headquarters, Walter Reed Army Medical Center, Washington, DC and Noncontiguous Sections Forest Glen, Silver Spring, Maryland and Glen Haven, Wheaton, Maryland.

    Science.gov (United States)

    1984-06-01

    Medicine, 2. Department of Surgery, 3. Department of Pediatrics , 4. Department of Obstetrics and Gynecology, 5. Department of Pathology and Area...Laboratory Services, 6. Department of Radiology, 7. Department of Primary Care and Community Medicine, 8. Department of Dentistry , 9. Allergy-Clinical...bridges, crowns , and dentures. Dilute quantities of waste reagents are 2-9 - p -. . . m • . . . . . . . .. . IIAWRAMC.2/PAST.8 2 /24/84 discharged to the

  20. The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006

    Science.gov (United States)

    Battaglin, William A.; Rice, Karen C.; Focazio, Michael J.; Salmons, Sue; Barry, Robert X.

    2009-01-01

    Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic acid, and additional pesticides in vernal pools and adjacent flowing waters. Most sampling sites were chosen to be in areas where glyphosate was being used either in production agriculture or for nonindigenous plant control. The four site locations were in otherwise protected areas (e.g., in a National Park). When possible, water samples were collected both before and after glyphosate application in 2005 and 2006. Twenty-eight pesticides or pesticide degradation products were detected in the study, and as many as 11 were identified in individual samples. Atrazine was detected most frequently and concentrations exceeded the freshwater aquatic life standard of 1.8 micrograms per liter (μg/l) in samples from Rands Ditch and Browns Ditch in DeSoto National Wildlife Refuge. Glyphosate was measured at the highest concentration (328 μg/l) in a sample from Riley Spring Pond in Rock Creek National Park. This concentration exceeded the freshwater aquatic life standard for glyphosate of 65 μg/l. Aminomethylphosphonic acid, triclopyr, and nicosulfuron also were detected at concentrations greater than 3.0 μg/l.

  1. The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006.

    Science.gov (United States)

    Battaglin, William A; Rice, Karen C; Focazio, Michael J; Salmons, Sue; Barry, Robert X

    2009-08-01

    Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic acid, and additional pesticides in vernal pools and adjacent flowing waters. Most sampling sites were chosen to be in areas where glyphosate was being used either in production agriculture or for nonindigenous plant control. The four site locations were in otherwise protected areas (e.g., in a National Park). When possible, water samples were collected both before and after glyphosate application in 2005 and 2006. Twenty-eight pesticides or pesticide degradation products were detected in the study, and as many as 11 were identified in individual samples. Atrazine was detected most frequently and concentrations exceeded the freshwater aquatic life standard of 1.8 micrograms per liter (microg/l) in samples from Rands Ditch and Browns Ditch in DeSoto National Wildlife Refuge. Glyphosate was measured at the highest concentration (328 microg/l) in a sample from Riley Spring Pond in Rock Creek National Park. This concentration exceeded the freshwater aquatic life standard for glyphosate of 65 microg/l. Aminomethylphosphonic acid, triclopyr, and nicosulfuron also were detected at concentrations greater than 3.0 microg/l.

  2. Q?rius: An innovative and new interactive educational space at the Smithsonian Institution's National Museum of Natural History, in Washington, D.C

    Science.gov (United States)

    Blankenbicker, R.

    2013-12-01

    The Fall of 2013 marks the opening of Q?rius ('curious'), a 10,000 square foot, interactive educational space at the Smithsonian Institution's National Museum of Natural History. Representing the 7 areas of the museum's research divisions, Q?rius includes a publicly accessible collection of over 6,000 natural history objects and multiple opportunities for visitors to engage themselves in natural history and the research conducted at the museum in various settings, including a lab, theater, and studio. A digital component to the space allows visitors to save parts of their experiences to a personal account, which they can later access remotely from their home or school. The space also serves as a tool for scientists to conduct outreach programs for museum visitors and for schools across the country through distance learning capabilities. Geology content for Q?rius was developed through collaboration between the Office of Education and Outreach and the Department of Mineral Sciences, as well as scientists and educators from outside agencies. Current experiences for the public include modeling plate tectonics and how they change rocks on small and large scales, identifying minerals in rocks, and using Earth to understand Martian geology. A school program adds the concept of drill cores and natural resources to the plate tectonics activity, which allows discussion about resource extraction. Developing experiences for Q?rius in all content areas took place over 2 phases; first, through taking prototypes into the museum exhibition halls to test with visitors through several iterations, and second in the new space, where all of the activities could be tested as a group and in the appropriate environment. By the time this abstract has been submitted, the official opening will not have occurred, though Q?rius will have been open for about 1 month by the time of the 2013 AGU annual conference, allowing us to further evaluate the development of the space.

  3. Geochemical and microbiological responses to oxidant introduction into reduced subsurface sediment from the Hanford 300 Area, Washington.

    Science.gov (United States)

    Percak-Dennett, Elizabeth M; Roden, Eric E

    2014-08-19

    Pliocene-aged reduced lacustrine sediment from below a subsurface redox transition zone at the 300 Area of the Hanford site (southeastern Washington) was used in a study of the geochemical response to introduction of oxygen or nitrate in the presence or absence of microbial activity. The sediments contained large quantities of reduced Fe in the form of Fe(II)-bearing phyllosilicates, together with smaller quantities of siderite and pyrite. A loss of ca. 50% of 0.5 M HCl-extractable Fe(II) [5-10 mmol Fe(II) L(-1)] and detectable generation of sulfate (ca. 0.2 mM, equivalent to 10% of the reduced inorganic sulfur pool) occurred in sterile aerobic reactors. In contrast, no systematic loss of Fe(II) or production of sulfate was observed in any of the other oxidant-amended sediment suspensions. Detectable Fe(II) accumulation and sulfate consumption occurred in non-sterile oxidant-free reactors. Together, these results indicate the potential for heterotrophic carbon metabolism in the reduced sediments, consistent with the proliferation of known heterotrophic taxa (e.g., Pseudomonadaceae, Burkholderiaceae, and Clostridiaceae) inferred from 16S rRNA gene pyrosequencing. Microbial carbon oxidation by heterotrophic communities is likely to play an important role in maintaining the redox boundary in situ, i.e., by modulating the impact of downward oxidant transport on Fe/S redox speciation. Diffusion-reaction simulations of oxygen and nitrate consumption coupled to solid-phase organic carbon oxidation indicate that heterotrophic consumption of oxidants could maintain the redox boundary at its current position over millennial time scales.

  4. Late Pleistocene and Holocene-Age Columbia River Sediments and Bedforms: Hanford Reach Area, Washington - Part 2

    Energy Technology Data Exchange (ETDEWEB)

    K.R. Fecht, T.E. Marceau

    2006-03-28

    This report presents the results of a geologic study conducted on the lower slopes of the Columbia River Valley in south-central Washington. The study was designed to investigate glaciofluvial and fluvial sediments and bedforms that are present in the river valley and formed subsequent to Pleistocene large-scale cataclysmic flooding of the region.

  5. Abundances of apple maggot, Rhagoletis pomonella, across different areas in central Washington, with special reference to black-fruited hawthorns

    Science.gov (United States)

    The apple maggot fly, Rhagoletis pomonella (Walsh), has infested native black-fruited hawthorn (mostly Crataegus douglasii Lindl.) in central Washington since at least 2003, but little is known about the fly’s ecology in hawthorns there. The main objective here was to determine adult and larval abu...

  6. A rigorous test of the accuracy of USGS digital elevation models in forested areas of Oregon and Washington.

    Science.gov (United States)

    Ward W. Carson; Stephen E. Reutebuch

    1997-01-01

    A procedure for performing a rigorous test of elevational accuracy of DEMs using independent ground coordinate data digitized photogrammetrically from aerial photography is presented. The accuracy of a sample set of 23 DEMs covering National Forests in Oregon and Washington was evaluated. Accuracy varied considerably between eastern and western parts of Oregon and...

  7. Child Sexual Abuse Prevention and Treatment Service Delivery Problems and Solutions in Rural Areas of Washington State.

    Science.gov (United States)

    Ray, JoAnn; Murty, Susan A.

    This study investigates prevention and treatment programs that deal with rural child sexual abuse in the State of Washington. A survey of 61 rural service providers examined agencies, services provided, problems faced in service delivery, and innovative solutions to those problems. The study compares responses from three types of agencies (mental…

  8. Socrates in Washington, D.C.

    Science.gov (United States)

    2008-08-01

    We wandered over to the Lincoln Memorial souvenir shop, which suddenly looked more out of place than our robed sage. He took all the postcards...turkeys offering to drive out the chaos or expecting you to do so. They try to put bad tools in yours hands—tools designed to increase certainty and

  9. Center for Applied Linguistics, Washington DC, USA

    Science.gov (United States)

    Sugarman, Julie; Fee, Molly; Donovan, Anne

    2015-01-01

    The Center for Applied Linguistics (CAL) is a private, nonprofit organization with over 50 years' experience in the application of research on language and culture to educational and societal concerns. CAL carries out its mission to improve communication through better understanding of language and culture by engaging in a variety of projects in…

  10. Privatizing Airports in Washington, D.C.

    Science.gov (United States)

    1983-02-01

    Omepe Be Wafs Aesept11i0 te Labar?" Avg 1976 (balted tsr policetlem is liifrell ad Labor Reltions Avion ), 40 pal 9n MPlufeseiMe Pows with an AD "Now a...1981) 66, Factors Affecting Iberian Security,- (Factors* Maritleas qiuo 421-439, AD A100 423 *AfeCtan Ill Seguridad Dancec) 14 pp., Oct 1980, AD

  11. Bidirectional DC/DC Converter

    Science.gov (United States)

    Pedersen, F.

    2008-09-01

    The presented bidirectional DC/DC converter design concept is a further development of an already existing converter used for low battery voltage operation.For low battery voltage operation a high efficient low parts count DC/DC converter was developed, and used in a satellite for the battery charge and battery discharge function.The converter consists in a bidirectional, non regulating DC/DC converter connected to a discharge regulating Buck converter and a charge regulating Buck converter.The Bidirectional non regulating DC/DC converter performs with relatively high efficiency even at relatively high currents, which here means up to 35Amps.This performance was obtained through the use of power MOSFET's with on- resistances of only a few mille Ohms connected to a special transformer allowing paralleling several transistor stages on the low voltage side of the transformer. The design is patent protected. Synchronous rectification leads to high efficiency at the low battery voltages considered, which was in the range 2,7- 4,3 Volt DC.The converter performs with low switching losses as zero voltage zero current switching is implemented in all switching positions of the converter.Now, the drive power needed, to switch a relatively large number of low Ohm , hence high drive capacitance, power MOSFET's using conventional drive techniques would limit the overall conversion efficiency.Therefore a resonant drive consuming considerable less power than a conventional drive circuit was implemented in the converter.To the originally built and patent protected bidirectional non regulating DC/DC converter, is added the functionality of regulation.Hereby the need for additional converter stages in form of a Charge Buck regulator and a Discharge Buck regulator is eliminated.The bidirectional DC/DC converter can be used in connection with batteries, motors, etc, where the bidirectional feature, simple design and high performance may be useful.

  12. 75 FR 68323 - Annual Surveys in the Manufacturing Area

    Science.gov (United States)

    2010-11-05

    ... Bureau of the Census Annual Surveys in the Manufacturing Area AGENCY: Bureau of the Census, Department of... the 2010 Annual Surveys in the Manufacturing Area. The 2010 Annual Surveys consist of the Current..., Washington, DC 20233-0101. FOR FURTHER INFORMATION CONTACT: Mendel D. Gayle, Chief, Manufacturing and...

  13. Chapter D. Effects of Urbanization on Stream Ecosystems in the Willamette River Basin and Surrounding Area, Oregon and Washington

    Science.gov (United States)

    Waite, Ian R.; Sobieszczyk, Steven; Carpenter, Kurt D.; Arnsberg, Andrew J.; Johnson, Henry M.; Hughes, Curt A.; Sarantou, Michael J.; Rinella, Frank A.

    2008-01-01

    This report describes the effects of urbanization on physical, chemical, and biological characteristics of stream ecosystems in 28 watersheds along a gradient of urbanization in the Willamette River basin and surrounding area, Oregon and Washington, from 2003 through 2005. The study that generated the report is one of several urban-effects studies completed nationally by the U.S. Geological Survey National Water-Quality Assessment Program. Watersheds were selected to minimize natural variability caused by factors such as geology, elevation, and climate, and to maximize coverage of different stages of urban development among watersheds. Because land use or population density alone often are not a complete measure of urbanization, a combination of land use, land cover, infrastructure, and socioeconomic variables were integrated into a multimetric urban intensity index (UII) to represent the degree of urban development in each watershed. Physical characteristics studied include stream hydrology, stream temperature, and habitat; chemical characteristics studied include sulfate, chloride, nutrients, pesticides, dissolved and particulate organic and inorganic carbon, and suspended sediment; and biological characteristics studied include algal, macroinvertebrate, and fish assemblages. Semipermeable membrane devices, passive samplers that concentrate trace levels of hydrophobic organic contaminants such as polycyclic aromatic hydrocarbons and polychlorinated biphenyls, also were used. The objectives of the study were to (1) examine physical, chemical, and biological responses along the gradient of urbanization and (2) determine the major physical, chemical, and landscape variables affecting the structure of aquatic communities. Common effects documented in the literature of urbanization on instream physical, chemical, and biological characteristics, such as increased contaminants, increased streamflow flashiness, increased concentrations of chemicals, and changes in

  14. DC + RSL

    DEFF Research Database (Denmark)

    Haxthausen, Anne

    1996-01-01

    This document gives some initial ideas of how the Duration Calculus (DC) can be integrated with the RAISE Specification Language (RSL).......This document gives some initial ideas of how the Duration Calculus (DC) can be integrated with the RAISE Specification Language (RSL)....

  15. Public awareness and attitudes towards naval sonar mitigation for cetacean conservation: a preliminary case study in Fairfax County, Virginia. (the DC Metro area).

    Science.gov (United States)

    Zirbel, K; Balint, P; Parsons, E C M

    2011-01-01

    The potential impacts of naval sonar on cetaceans has led to a series of court cases and statements of concern by international organizations. However, there has been no research conducted on attitudes of the general public with respect to this issue. To investigate this, a preliminary public survey was conducted in Fairfax, Virginia (the Washington, DC Metro region). The majority of the public sampled believed that naval sonar impacted marine mammals (51.3%), that the US Navy should not be exempt from environmental regulations in time of peace (75.2%), and that sonar use should be moderated if it impacts cetaceans (75.8%). Individuals who were conservative, Republican, and have served in the military were more likely to believe the Navy should be exempt from marine mammal protection regulations. In addition, expert interviews were conducted to gain opinions on the potential ramifications of the recent US Supreme Court case on naval sonar mitigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Assessing urban forest effects and values, Washington, D.C.'s urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2006-01-01

    An analysis of trees in Washington, D.C. reveals that this city has about 1,928,000 trees with canopies that cover 28.6 percent of the area. The most common tree species are American beech, red maple, and boxelder. The urban forest currently store about 526,000 tons of carbon valued at $9.7 million. In addition, these trees remove about 16,200 tons of carbon per year...

  17. Electronic media time and sedentary behaviors in children: Findings from the Built Environment and Active Play Study in the Washington DC area

    National Research Council Canada - National Science Library

    Roberts, Jennifer D; Rodkey, Lindsey; Ray, Rashawn; Knight, Brandon; Saelens, Brian E

    2017-01-01

    An objective of the Built Environment and Active Play (BEAP) Study was to examine whether home built environment, bedroom electronic presence, parental rules and demographics predicted children's sedentary behavior (SB...

  18. Aerial Photography and Imagery, Ortho-Corrected, Washington County, NC true color orthophotography - 1/4 foot resolution over selected areas, Published in 2009, 1:1200 (1in=100ft) scale, Washington County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Aerial Photography and Imagery, Ortho-Corrected dataset current as of 2009. Washington County, NC true color orthophotography - 1/4 foot resolution over selected...

  19. 24 CFR 1710.13 - Metropolitan Statistical Area (MSA) exemption.

    Science.gov (United States)

    2010-04-01

    ... Affairs, Office of Management and Budget, 726 Jackson Place, NW., Washington, DC 20503. (c) The sale must... HOUSING AND URBAN DEVELOPMENT (INTERSTATE LAND SALES REGISTRATION PROGRAM) LAND REGISTRATION General Requirements § 1710.13 Metropolitan Statistical Area (MSA) exemption. (a) Eligibility requirements. The sale of...

  20. Effect of a liver cancer education program on hepatitis B screening among Asian Americans in the Baltimore-Washington metropolitan area, 2009-2010.

    Science.gov (United States)

    Juon, Hee-Soon; Lee, Sunmin; Strong, Carol; Rimal, Rajiv; Kirk, Gregory D; Bowie, Janice

    2014-02-06

    Asian Americans have the highest incidence of hepatocellular carcinoma (HCC), the major form of primary liver cancer, of all ethnic groups in the United States. Chronic hepatitis B virus (HBV) infection is the most common cause of HCC, and as many as 1 in 10 foreign-born Asian Americans are chronically infected with HBV. We tested the effectiveness of a culturally tailored liver cancer education program for increasing screening for HBV among Chinese, Korean, and Vietnamese Americans residing in the Baltimore-Washington metropolitan area, from November 2009 through June 2010. We used a cluster randomized controlled trial to recruit volunteer participants from community-based organizations (CBOs) in the Baltimore-Washington metropolitan area. We selected 877 participants by using a pretest survey. People were eligible to participate if they had not attended a hepatitis B-related education program in the past 5 years. The intervention group (n = 441) received a 30-minute educational program, and the control group (n = 436) received an educational brochure. After attending the educational program, the intervention group completed a post-education survey. Six months later, participants in both groups were followed up by telephone. Receipt of HBV screening was the outcome measure. Approximately 79% (n = 688) of participants completed the 6-month follow-up telephone survey. Among those who had not had HBV screening at baseline (n = 446), the adjusted odds of self-reported receipt of HBV screening at the 6-month follow-up to the educational program were significantly higher for the intervention group than for the control group (odds ratio = 5.13; 95% confidence interval, 3.14-8.39; P Americans and Vietnamese Americans had significantly higher odds of having HBV screening in the 6-month period than Korean Americans. Culturally tailored education programs that increase liver cancer awareness can be effective in increasing HBV screening among underserved Asian American

  1. DC electric springs with DC/DC converters

    DEFF Research Database (Denmark)

    Wang, Qingsong; Cheng, Ming; Jiang, Yunlei

    2016-01-01

    The concept of DC electric spring (DCES) was recently proposed to solve the stability issue caused by integrating intermittent renewable energy sources (RESs) to DC microgrids. In this paper, a new topology of DCES is proposed based on DC/DC converters. The proposed DCES consists of a bi-directio......The concept of DC electric spring (DCES) was recently proposed to solve the stability issue caused by integrating intermittent renewable energy sources (RESs) to DC microgrids. In this paper, a new topology of DCES is proposed based on DC/DC converters. The proposed DCES consists of a bi...

  2. Map showing geochemical data for panned stream sediments from the Bread Loaf Further Planning Area, Addison and Washington counties, Vermont

    Science.gov (United States)

    Grosz, A.E.; Schruben, P.G.; Atelsek, P.J.

    1987-01-01

    A geochemical survey of bedrock samples in the Bread Loaf Roadless Area (index map; fig. 1) was conducted by the U.S. Geological Survey (USGS) during October, 1981 in order to outline areas that may contain undiscovered mineral deposits. This report describes the results of a geochemical analysis of panned concentrates collected from stream sediments, and complements other geologic and geochemical investigations of the area (Slack and Bitar, 1983). The present study has offered us a chance to identify sampling media and a technique most appropriate for the enhancement of certain metallic elements in samples of panned concentrate. This study is important to the resource evaluation of the Bread Loaf Roadless Area because it reveals that geochemical anomalies produced by this technique are not evident in the standard magnetic and nonmagnetic fractions of panned concentrates.

  3. 2012 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Chehalis River Watershed Area, Washington

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. (WSI) collected Light Detection and Ranging (LiDAR) data for the Chehalis River Watershed study area on January 28th, February 2nd-7th,...

  4. 2016 Cartographic Boundary File, 2010 Urban Areas (UA) within 2010 County and Equivalent for Washington, 1:500,000

    Data.gov (United States)

    US Census Bureau, Department of Commerce — The 2016 cartographic boundary KMLs are simplified representations of selected geographic areas from the U.S. Census Bureau's Master Address File / Topologically...

  5. Interim Status Groundwater Monitoring Plan for Low-Level Waste Management Areas 1 to 4, RCRA Facilities, Hanford,Washington

    Energy Technology Data Exchange (ETDEWEB)

    Dresel, P Evan

    2004-10-25

    This document describes the monitoring plan to meet the requirements for interim status groundwater monitoring at Hanford Site low-level waste burial grounds as specified by 40 CFR 265, incorporated by reference in WAC 173-303-400. The monitoring will take place at four separate low-level waste management areas in the 200-West and 200-East Areas, in the central part of the site. This plan replaces the previous monitoring plan.

  6. Monitoring recharge in areas of seasonally frozen ground in the Columbia Plateau and Snake River Plain, Idaho, Oregon, and Washington

    Science.gov (United States)

    Mastin, Mark; Josberger, Edward

    2014-01-01

    Seasonally frozen ground occurs over approximately one‑third of the contiguous United States, causing increased winter runoff. Frozen ground generally rejects potential groundwater recharge. Nearly all recharge from precipitation in semi-arid regions such as the Columbia Plateau and the Snake River Plain in Idaho, Oregon, and Washington, occurs between October and March, when precipitation is most abundant and seasonally frozen ground is commonplace. The temporal and spatial distribution of frozen ground is expected to change as the climate warms. It is difficult to predict the distribution of frozen ground, however, because of the complex ways ground freezes and the way that snow cover thermally insulates soil, by keeping it frozen longer than it would be if it was not snow covered or, more commonly, keeping the soil thawed during freezing weather. A combination of satellite remote sensing and ground truth measurements was used with some success to investigate seasonally frozen ground at local to regional scales. The frozen-ground/snow-cover algorithm from the National Snow and Ice Data Center, combined with the 21-year record of passive microwave observations from the Special Sensor Microwave Imager onboard a Defense Meteorological Satellite Program satellite, provided a unique time series of frozen ground. Periodically repeating this methodology and analyzing for trends can be a means to monitor possible regional changes to frozen ground that could occur with a warming climate. The Precipitation-Runoff Modeling System watershed model constructed for the upper Crab Creek Basin in the Columbia Plateau and Reynolds Creek basin on the eastern side of the Snake River Plain simulated recharge and frozen ground for several future climate scenarios. Frozen ground was simulated with the Continuous Frozen Ground Index, which is influenced by air temperature and snow cover. Model simulation results showed a decreased occurrence of frozen ground that coincided with

  7. GLASS FORMULATION TESTING TO INCREASE SULFATE INCORPORATION - Final Report VSL-04R4960-1, Rev 0, 2/28/05, Vitreous State Laboratory, The Catholic University of American, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    KRUGER AA; MATLACK KS

    2012-02-07

    About 50 million gallons of high-level mixed waste is currently in storage in underground tanks at The United States Department of Energy's (DOE's) Hanford site in the State of Washington. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) will provide DOE's Office of River Protection (ORP) with a means of treating this waste by vitrification for subsequent disposal. The tank waste will be separated into low- and high-activity fractions, which will then be vitrified respectively into Immobilized Low Activity Waste (ILAW) and Immobilized High Level Waste (IHLW) products. The ILAW product will be disposed of in an engineered facility on the Hanford site while the IHLW product will be directed to the national deep geological disposal facility for high-level nuclear waste. The ILAW and IHLW products must meet a variety of requirements with respect to protection of the environment before they can be accepted for disposal. The Office of River Protection is currently examining options to optimize the Low Activity Waste (LAW) facility and the LAW glass waste form. One option under evaluation is to enhance the waste processing rate of the vitrification plant currently under construction. It is likely that the capacity of the LAW vitrification plant can be increased incrementally by implementation of a variety of low-risk, high-probability changes, either separately or in combination. These changes include: (1) Operating at the higher processing rates demonstrated at the LAW Pilot Melter; (2) Increasing the glass pool surface area within the existing external melter envelope; (3) Increasing plant availability; (4) Increasing the glass waste loading; (5) Removing sulfate from the LAW stream; (6) Operating the melter at slightly higher temperature; (7) Installing the third LAW melter into the WTP plant; and (8) Other smaller impact changes. The melter tests described in this report utilized blended feed (glass formers plus waste simulant) prepared

  8. RESULTS FROM RECENT SCIENCE AND TECHNOLOGY INVESTIGATIONS TARGETING CHROMIUM IN THE 100D AREA HANFORD SITE WASHINGTON USA

    Energy Technology Data Exchange (ETDEWEB)

    PETERSEN SW; THOMPSON KM; TONKIN MJ

    2009-12-03

    Sodium dichromate was used in Hanford's 100D Area during the reactor operations period of 1950 to 1964 to retard corrosion in the reactor cooling systems. Some of the sodium dichromate was released to the environment by spills and/or leaks from pipelines used to deliver the chemical to water treatment plants in the area. As a result, hexavalent chromium [Cr(VI)] has migrated through the vadose zone to the groundwater and contaminated nearly 1 km{sup 2} of groundwater to above the drinking water standard of 48 {micro}g/L. Three technology tests have recently been completed in this area to characterize the source area of the plumes and evaluate alternative methods to remove Cr(VI) from groundwater. These are (1) refine the source area of the southern plume; (2) test electrocoagulation as an alternative groundwater treatment technology; and (3) test the ability to repair a permeable reactive barrier by injecting micron or nanometer-size zero-valent iron (ZVI). The projects were funded by the US Department of Energy as part of a program to interject new technologies and accelerate active cleanup. Groundwater monitoring over the past 10 years has shown that Cr(VI) concentrations in the southern plume have not significantly diminished, strongly indicating a continuing source. Eleven groundwater wells were installed in 2007 and 2008 near a suspected source area and monitored for Cr(VI) and groundwater levels. Interpretation of these data has led to refinement of the source area location to an area of less than 1 hectare (ha, 2.5 acres). Vadose zone soil samples collected during drilling did not discover significant concentrations of Cr(VI), indicating the source is localized, with a narrow wetted path from the surface to the water table. Electrocoagulation was evaluated through a pilot-scale treatability test. Over 8 million liters of groundwater were treated to Cr(VI) concentrations of {le}20 {micro}g/L. The test determined that this technology has the potential to

  9. Decision Document for the Storm Water Outfalls/Industrial Wastewater Treatment Plant, Pesticide Rinse Area, Old Fire Fighting Training Pit, Illicit PCB Dump Site, and the Battery Acid Pit Fort Lewis, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J.; Liikala, Terry L.; Strenge, Dennis L.; Taira, Randal Y.

    2000-12-11

    PNNL conducted independent site evaluations for four sites at Fort Lewis, Washington, to determine their suitability for closure on behalf of the installation. These sites were recommended for "No Further Action" by previous invesitgators and included the Storm Water Outfalls/Industrial Waste Water Treatment Plant (IWTP), the Pesticide Rinse Area, the Old Fire Fighting Training Pit, and the Illicit PCB Dump Site.

  10. Drilling history core hole DC-8

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-01

    Core hole DC-8 was completed in August, 1978 by Boyles Brothers Drilling Company, Spokane, Washington, under subcontract to Fenix and Scission, Inc. The hole was cored for the US Department of Energy and the Rockwell Hanford Operations' Basalt Waste Isolation Program. Fenix and Scisson, Inc. furnished the engineering, daily supervision of the core drilling activities, and geologic core logging for hole DC-8. Core hole DC-8 is located on the Hanford Site near the Wye Barricade and 50 feet northwest of rotary hole DC-7. The Hanford Site vation coordinates for DC-8 are North 14,955.94 feet and West 14,861.92 coordinates for DC-8 are North 14,955.94 feet and West 14,861.92 mean sea level. The purpose of core hole DC-8 was to core drill vertically through the basalt and interbed units for stratigraphic depth determination and core collection, and to provide a borehole for hydrologic testing and cross-hole seismic shear and pressure wave velocity studies with rotary hole DC-7. The total depth of core hole DC-8 was 4100.5 feet. Core recovery exceeded 97 percent of the total footage cored.

  11. Step-Up DC-DC converters

    DEFF Research Database (Denmark)

    Forouzesh, Mojtaba; Siwakoti, Yam P.; Gorji, Saman A.

    2017-01-01

    on the general law and framework of the development of next-generation step-up dc-dc converters, this paper aims to comprehensively review and classify various step-up dc-dc converters based on their characteristics and voltage-boosting techniques. In addition, the advantages and disadvantages of these voltage...

  12. Use of electrical imaging and distributed temperature sensing methods to characterize surface water-groundwater exchange regulating uranium transport at the Hanford 300 Area, Washington

    Science.gov (United States)

    Slater, Lee D.; Ntarlagiannis, Dimitrios; Day-Lewis, Frederick D.; Mwakanyamale, Kisa; Versteeg, Roelof J.; Ward, Andy; Strickland, Christopher; Johnson, Carole D.; Lane, John W.

    2010-10-01

    We explored the use of continuous waterborne electrical imaging (CWEI), in conjunction with fiber-optic distributed temperature sensor (FO-DTS) monitoring, to improve the conceptual model for uranium transport within the Columbia River corridor at the Hanford 300 Area, Washington. We first inverted resistivity and induced polarization CWEI data sets for distributions of electrical resistivity and polarizability, from which the spatial complexity of the primary hydrogeologic units was reconstructed. Variations in the depth to the interface between the overlying coarse-grained, high-permeability Hanford Formation and the underlying finer-grained, less permeable Ringold Formation, an important contact that limits vertical migration of contaminants, were resolved along ˜3 km of the river corridor centered on the 300 Area. Polarizability images were translated into lithologic images using established relationships between polarizability and surface area normalized to pore volume (Spor). The FO-DTS data recorded along 1.5 km of cable with a 1 m spatial resolution and 5 min sampling interval revealed subreaches showing (1) temperature anomalies (relatively warm in winter and cool in summer) and (2) a strong correlation between temperature and river stage (negative in winter and positive in summer), both indicative of reaches of enhanced surface water-groundwater exchange. The FO-DTS data sets confirm the hydrologic significance of the variability identified in the CWEI and reveal a pattern of highly focused exchange, concentrated at springs where the Hanford Formation is thickest. Our findings illustrate how the combination of CWEI and FO-DTS technologies can characterize surface water-groundwater exchange in a complex, coupled river-aquifer system.

  13. Use of electrical imaging and distributed temperature sensing methods to characterize surface water-groundwater exchange regulating uranium transport at the Hanford 300 Area, Washington

    Science.gov (United States)

    Slater, Lee D.; Ntarlagiannis, Dimitrios; Day-Lewis, Frederick D.; Mwakanyamale, Kisa; Versteeg, Roelof J.; Ward, Andy; Strickland, Christopher; Johnson, Carole D.; Lane, John W.

    2010-01-01

    We explored the use of continuous waterborne electrical imaging (CWEI), in conjunction with fiber-optic distributed temperature sensor (FO-DTS) monitoring, to improve the conceptual model for uranium transport within the Columbia River corridor at the Hanford 300 Area, Washington. We first inverted resistivity and induced polarization CWEI data sets for distributions of electrical resistivity and polarizability, from which the spatial complexity of the primary hydrogeologic units was reconstructed. Variations in the depth to the interface between the overlying coarse-grained, high-permeability Hanford Formation and the underlying finer-grained, less permeable Ringold Formation, an important contact that limits vertical migration of contaminants, were resolved along ∼3 km of the river corridor centered on the 300 Area. Polarizability images were translated into lithologic images using established relationships between polarizability and surface area normalized to pore volume (Spor). The FO-DTS data recorded along 1.5 km of cable with a 1 m spatial resolution and 5 min sampling interval revealed subreaches showing (1) temperature anomalies (relatively warm in winter and cool in summer) and (2) a strong correlation between temperature and river stage (negative in winter and positive in summer), both indicative of reaches of enhanced surface water–groundwater exchange. The FO-DTS data sets confirm the hydrologic significance of the variability identified in the CWEI and reveal a pattern of highly focused exchange, concentrated at springs where the Hanford Formation is thickest. Our findings illustrate how the combination of CWEI and FO-DTS technologies can characterize surface water–groundwater exchange in a complex, coupled river-aquifer system.

  14. Environmental Assessment for the Transfer of 1100 AREA, Southern Rail Connection and Rolling Stock, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1998-08-01

    This environmental assessment (EA) has been prepared to assess potential environmental impacts associated with the U.S. Department of Energy's proposed action: the transfer of the 1100 Area, southern rail connection and rolling stock to a non-federal entity. Impact information contained herein will be used by the U.S. Department of Energy, Richland Operations Office Manager, to determine if the proposed action is a major federal action significantly affecting the quality of the human environment. If the proposed action is determined to be major and significant, an environmental impact statement will be prepared. If the proposed action is determined not to be major and significant, a Finding of No Significant Impact (FONSI) will be issued and the action can proceed. Criteria used to evaluate significance can be found in Title 40, Code of Federal Regulations (CFR) 1508.27. This EA was prepared in compliance with the ''National Environmental Policy Act'' (NEPA) of 1969, as amended, the Council on Environmental Quality (CEQ) Regulations for Implementing the Procedural Provisions of NEPA (40 CFR 1500-1508), and the U.S. Department of Energy Implementing Procedures for NEPA (10 CFR 1021). The following is a description of each section of the EA. (1) Purpose and Need for Action. This provides a brief statement concerning the problem or opportunity the U.S. Department of Energy is addressing with the proposed action. As necessary, background information is provided. (2) Description of the Proposed Action. A description with sufficient detail to identify potential environmental impacts is provided. (3) Alternatives to the Proposed Action. Reasonable alternative actions, which would address the Purpose and Need, are described. A no action alternative, as required by 10 CFR 1021, also is described. (4) Affected Environment. This provides a brief description of the locale in which the proposed action takes place, and which may be environmentally

  15. Electrical geophysical characterization of the Hanford 300 Area Integrated Field Research Challenge using high performance DC resistivity inversion geostatistically constrained by borehole conductivity logs

    Science.gov (United States)

    Johnson, T. C.; Versteeg, R. J.; Ward, A. L.; Strickland, C. E.; Greenwood, J.

    2009-12-01

    The Hanford 300 Area Integrated Field Research Challenge is a DOE funded multi-institution field study designed to better understand the field scale subsurface processes governing uranium transport in the Hanford 300 Area and other DOE sites. The primary focus area includes 28 monitoring wells spaced approximately 10 meters apart and extending downward 18 meters through the unconfined aquifer to a lower fine-grained confining unit. Each well is equipped with 15 permanent electrodes in the vadose zone and 15 removable electrodes in the saturated zone for a total 840 electrodes. To characterize the electrical conductivity structure of the site, a set of 32 overlapping 3D DC resistivity surveys were conducted where each survey included 4 adjacent wells. The complete set of surveys comprises approximately 150,000 resistivity measurements. We demonstrate the characterization by inverting the complete data set using a parallel resistivity modeling/inversion code developed at the Idaho National Laboratory. We compare two approaches; 1) an Occam minimum-structure type inversion, and 2) an inversion using geostatistical and borehole conductivity constraints. The first inversion shows the larger scale conductivity features of the site as resolved by the resistivity data only. The second inversion provides solutions which honor the resistivity data, the directional and zonal semivariograms derived from borehole conductivity logs, and the corresponding borehole conductivities. This approach allows an ensemble of solutions to be generated which incorporate uncertainty in both the semivariograms and the resistivity data. Assuming electrical conductivity is well correlated with hydrogeologic properties at the site, this ensemble of models can be used, along with appropriate petrophyiscal transforms, to generate an ensemble of hydrogeologic models which can ultimately be used to investigate uncertainty in flow and transport processes.

  16. Sampling for Paralytic Shellfish Poisoning in commercial and recreational shellfish areas in Washington state marine waters, 1957 - 1988 (NODC Accession 0000597)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes,...

  17. Sampling for Paralytic Shellfish Poisoning in commercial and recreational shellfish areas in Washington state marine waters, January - December 2000 (NODC Accession 0000559)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes,...

  18. Nature of the contact zone between the North Cascades crystalline core and the Methow Sequence In the Ross Lake Area, Washington: Implications for Cordilleran tectonics

    Science.gov (United States)

    Kriens, Bryan; Wernicke, Brian

    1990-10-01

    Previous analyses of the accretionary history of NW Washington-SW British Columbia have suggested the possibility of large-scale, dextral-slip faulting events to explain the present day regional outcrop pattern. The contact zone between the crystalline Skagit Complex and the volcano-sedimentary Methow sequence has been considered to be a major fault, named the Ross Lake fault by Misch (1966), and has been considered to be a possible large-scale strike-slip fault by later workers. Detailed mapping of this contact zone in the Ross Lake area shows that the brittle faults and mylonites thought by Misch to express dextral shearing along the contact are not continuous, throughgoing structures, and that the contact between Skagit orthogneisses and Methow sequence strata is primarily intrusive. Furthermore, the mylonites show both left- and right-lateral shear. The Skagit-Methow contact is therefore not a major terrane boundary but rather a tectonized intrusive contact that has not accommodated significant motion between the two regions. Based on these observations and regional synthesis of timing relations, deformation in the contact zone is interpreted to express regional ENE-WSW shortening, not major dextral slip, in the early Tertiary. Since no terrane-bounding fault exists, the Cretaceous-Tertiary history of the Ross Lake area can be interpreted as follows: (1) Jurassic(?)-Early Cretaceous forearc/rift basin sedimentation (deposition of the lower Methow sequence); (2) 110-95 Ma, imbrication of the lower Methow sequence and its basement of oceanic crustal rocks by east-vergent thrusting, with concomitant development of a west-derived foredeep in the upper Methow sequence; (3) 95-85 Ma, arc magmatism, with genesis of the Skagit migmatite from Methow and older basement protoliths; and (4) Paleocene-Early Eocene folding, faulting, uplift, and exposure of a relatively intact 25+ km crustal section, termed the Skagit-Methow crustal section by Kriens and Wernicke (1987).

  19. A resonant dc-dc power converter assembly

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor of the s......The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor...

  20. DC Home Appliances for DC Distribution System

    Directory of Open Access Journals (Sweden)

    MUHAMMAD KAMRAN

    2017-10-01

    Full Text Available This paper strengthens the idea of DC distribution system for DC microgrid consisting of a building of 50 apartments. Since the war of currents AC system has been dominant because of the paucity of research in the protection of the DC system. Now with the advance research in power electronics material and components, generation of electricity is inherently DC as by solar PV, fuel cell and thermoelectric generator that eliminates the rectification process. Transformers are replaced by the power electronics buck-boost converters. DC circuit breakers have solved the protection problems for both DC transmission and distribution system. In this paper 308V DC microgrid is proposed and home appliances (DC internal are modified to operate on 48V DC from DC distribution line. Instead of using universal and induction motors in rotary appliances, BLDC (Brushless DC motors are proposed that are highly efficient with minimum electro-mechanical and no commutation losses. Proposed DC system reduces the power conversion stages, hence diminishes the associated power losses and standby losses that boost the overall system efficiency. So in view of all this a conventional AC system can be replaced by a DC system that has many advantages by cost as well as by performance

  1. The Boring Volcanic Field of the Portland-Vancouver area, Oregon and Washington: tectonically anomalous forearc volcanism in an urban setting

    Science.gov (United States)

    Evarts, Russell C.; Conrey, Richard M.; Fleck, Robert J.; Hagstrum, Jonathan T.; O'Connor, Jim; Dorsey, Rebecca; Madin, Ian P.

    2009-01-01

    More than 80 small volcanoes are scattered throughout the Portland-Vancouver metropolitan area of northwestern Oregon and southwestern Washington. These volcanoes constitute the Boring Volcanic Field, which is centered in the Neogene Portland Basin and merges to the east with coeval volcanic centers of the High Cascade volcanic arc. Although the character of volcanic activity is typical of many monogenetic volcanic fields, its tectonic setting is not, being located in the forearc of the Cascadia subduction system well trenchward of the volcanic-arc axis. The history and petrology of this anomalous volcanic field have been elucidated by a comprehensive program of geologic mapping, geochemistry, 40Ar/39Ar geochronology, and paleomag-netic studies. Volcanism began at 2.6 Ma with eruption of low-K tholeiite and related lavas in the southern part of the Portland Basin. At 1.6 Ma, following a hiatus of ~0.8 m.y., similar lavas erupted a few kilometers to the north, after which volcanism became widely dispersed, compositionally variable, and more or less continuous, with an average recurrence interval of 15,000 yr. The youngest centers, 50–130 ka, are found in the northern part of the field. Boring centers are generally monogenetic and mafic but a few larger edifices, ranging from basalt to low-SiO2 andesite, were also constructed. Low-K to high-K calc-alkaline compositions similar to those of the nearby volcanic arc dominate the field, but many centers erupted magmas that exhibit little influence of fluids derived from the subducting slab. The timing and compositional characteristics of Boring volcanism suggest a genetic relationship with late Neogene intra-arc rifting.

  2. What Can the Federal Government Do To Decrease Crime and Revitalize Communities? Panel Papers from the Department of Justice Symposium (Washington, D.C., January 5-7, 1998).

    Science.gov (United States)

    Department of Justice, Washington, DC. National Inst. of Justice.

    These panel papers address various ways to meet the needs of changing communities in achieving the goal of reducing crime and revitalizing communities. Weeding out crime and seeding target areas with social services and economic revitalization calls for a range of strategies, as identified by the panelists. The following papers are included: (1)…

  3. Washington's public and private forests.

    Science.gov (United States)

    Charles L. Bolsinger; Neil McKay; Donald FL Gedney; Carol. Alerich

    1997-01-01

    This report summarizes and analyzes 1988-91 timber inventories of western and eastern Washington. These inventories were conducted on all private and public lands except National Forests. Timber resource statistics from National Forest inventories also are presented. Detailed tables provide estimates of forest area, timber volume, growth, mortality, and harvest. Data...

  4. Soft switched DC-DC converter

    Science.gov (United States)

    Subramanian, K.; Kavitha, K. V. N.; Saravanan, K.

    2017-11-01

    A soft switched single switch isolated dc-dc conveys proposed in this paper. This converter works on the principle of zero current switching (zcs) and zero voltage switching (zvs). The circuit comprises lossless snubber with low rating. The switch works on zcs during turn on and zvs during turnoff. The diodes are based on zcs turn on and turnoff conditions. This paper presents the concept of soft switching and its applications to dc-dc converter. The losses due to soft switching and hard switching are compared.

  5. IGBT Based DC/DC Converter

    Directory of Open Access Journals (Sweden)

    M. Akherraz

    1997-12-01

    Full Text Available This paper presents an in-depth analytical and experimental investigation of an indirect DC-DC converter. The DC-AC conversion is a full bridge based on IGBT power modules, and the AC-DC conversion is done via a high  frequency AC link and a first diode bridge. The AC link, which consists of snubbing capacitors and a variable air-gap transformer, is analytically designed to fulfill Zero Voltage commutation requirement. The proposed converter is simulated using PSPICE and a prototype is designed built and tested in the laboratory. PSPICE simulation and experimental results are presented and compared.

  6. 1979-1980 Geothermal Resource Assessment Program in Washington

    Energy Technology Data Exchange (ETDEWEB)

    Korosec, M.A.; Schuster, J.E.

    1980-01-01

    Separate abstracts were prepared for seven papers. Also included are a bibliography of geothermal resource information for the State of Washington, well temperature information and locations in the State of Washington, and a map of the geology of the White Pass-Tumac Mountain Area, Washington. (MHR)

  7. 1975 Washington timber harvest.

    Science.gov (United States)

    J.D. Jr. Lloyd

    1977-01-01

    In 1975, the Washington timber harvest declined for the 2d year to 6.2 billion board feet, 10 percent below 1974, and the lowest level in 8 years. The decrease, which occurred on almost all ownerships, amounted to 561 million board feet in western Washington and 130 million board feet in eastern Washington.

  8. DC grid for home applications

    Science.gov (United States)

    Elangovan, D.; Archana, R.; Jayadeep, V. J.; Nithin, M.; Arunkumar, G.

    2017-11-01

    More than fifty percent Indian population do not have access to electricity in daily lives. The distance between the power generating stations and the distribution centers forms one of the main reasons for lack of electrification in rural and remote areas. Here lies the importance of decentralization of power generation through renewable energy resources. In the present world, electricity is predominantly powered by alternating current, but most day to day devices like LED lamps, computers and electrical vehicles, all run on DC power. By directly supplying DC to these loads, the number of power conversion stages was reduced, and overall system efficiency increases. Replacing existing AC network with DC is a humongous task, but with power electronic techniques, this project intends to implement DC grid at a household level in remote and rural areas. Proposed work was designed and simulated successfully for various loads amounting to 250 W through appropriate power electronic convertors. Maximum utilization of the renewable sources for domestic and commercial application was achieved with the proposed DC topology.

  9. Teaching about operation of brushless DC motors

    OpenAIRE

    Čufar, Aleksandra

    2013-01-01

    Brush DC motor is being replaced by brushless DC motors on every area of application. My diploma thesis is a presentation of brushless DC motor, how it works and its application. Within first part we describe various electric motors and their application. There are several types of electric motors division. Last to be added is a brushless motor. Within second part of thesis we look into a brushless DC motor, how it works, its application and control. In the third part of thesis we construct a...

  10. Nutritional and safety assessments of foods and feeds nutritionally improved through biotechnology: case studies: executive summary of a task force report by the International Life Sciences Institute, Washington, D.C.

    Science.gov (United States)

    2007-11-01

    During the last 2 decades, the public and private sectors have made substantial international research progress toward improving the nutritional value of a wide range of food and feed crops. Nevertheless, significant numbers of people still suffer from the effects of undernutrition. In addition, the nutritional quality of feed is often a limiting factor in livestock production systems, particularly those in developing countries. As newly developed crops with nutritionally improved traits come closer to being available to producers and consumers, we must ensure that scientifically sound and efficient processes are used to assess the safety and nutritional quality of these crops. Such processes will facilitate deploying these crops to those world areas with large numbers of people who need them. This document describes 5 case studies of crops with improved nutritional value. These case studies examine the principles and recommendations published by the Intl. Life Sciences Inst. (ILSI) in 2004 for the safety and nutritional assessment of foods and feeds derived from nutritionally improved crops (ILSI 2004). One overarching conclusion that spans all 5 case studies is that the comparative safety assessment process is a valid approach. Such a process has been endorsed by many publications and organizations, including the 2004 ILSI publication. The type and extent of data that are appropriate for a scientifically sound comparative safety assessment are presented on a case-by-case basis in a manner that takes into account scientific results published since the 2004 ILSI report. This report will appear in the January issue of Comprehensive Reviews in Food Science and Food Safety.

  11. A Review of the Environmental Impacts for Marine and Hydrokinetic Projects to Inform Regulatory Permitting: Summary Findings from the 2015 Workshop on Marine and Hydrokinetic Technologies, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    Baring-Gould, E. Ian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Christol, Corrie [National Renewable Energy Lab. (NREL), Golden, CO (United States); LiVecchi, Al [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kramer, Sharon [H.T. Harvey and Associates, Los Gatos, CA (United States); West, Anna [Kearns & West, Inc., San Francisco, CA (United States)

    2016-07-01

    In 2014 and 2015, the U.S. Department of Energy initiated efforts to develop and implement technology- and application-focused marine and hydrokinetic (MHK) workshops to share the global experience and knowledge base on evolving MHK technologies, observed and not-observed impacts, monitoring and measurement methods, and regulatory needs. The resulting MHK Regulator Workshops engaged resource managers and other decision makers at key regulatory organizations, scientists, researchers, facilitators, and technical experts and provided an opportunity to examine the risks of single-device and small-scale deployments, explore what can be learned and observed from single devices and small-scale arrays, and consider requirements for projects at varying scales of deployment. Experts and stakeholders identified key remaining information gaps. Initial discussions focused on differentiating between monitoring required for single or small-scale deployments and MHK impact research that, although important, goes beyond what is feasible or should be needed to meet specific project regulatory requirements but is appropriate for broader research and development. Four areas of identified potential environmental impacts provided the focus for the workshop: acoustic output impacts, electromagnetic field (EMF) emissions, physical interactions, and environmental effects of MHK energy development on the physical environment. Discussions also focused on the regulatory process and experience, adaptive management, industry drivers, and lessons that can be learned from the wind energy industry. The discussion was set in the context of the types of MHK technologies that are currently proposed or planned in the United States. All presentations and the following discussions are summarized in this document.

  12. Focus on: Washington Hospital Center, Biomedical Engineering Department.

    Science.gov (United States)

    Hughes, J D

    1995-01-01

    The Biomedical Engineering Department of the Washington Hospital Center provides clinical engineering services to an urban 907-bed, tertiary care teaching hospital and a variety of associated healthcare facilities. With an annual budget of over $3,000,000, the 24-person department provides cradle-to-grave support for a host of sophisticated medical devices and imaging systems such as lasers, CT scanners, and linear accelerators as well as traditional patient care instrumentation. Hallmarks of the department include its commitment to customer service and patient care, close collaboration with clinicians and quality assurance teams throughout the hospital system, proactive involvement in all phases of the technology management process, and shared leadership in safety standards with the hospital's risk management group. Through this interactive process, the department has assisted the Center not only in the acquisition of 11,000 active devices with a value of more than $64 million, but also in becoming one of the leading providers of high technology healthcare in the Washington, DC metropolitan area.

  13. 76 FR 31462 - Airworthiness Directives; The Boeing Company Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10...

    Science.gov (United States)

    2011-06-01

    ... Model DC-10-10, DC- 10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F.... Applicability (c) This AD applies to all The Boeing Company Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10- 40, DC-10-40F, MD-10-10F, MD-10-30F, MD-11, and MD-11F airplanes...

  14. An Investigation of DC-DC Converter Power Density Using Si and SiC MOSFETS

    Science.gov (United States)

    2010-05-07

    were fabricated by Cree Inc., for use in vehicular converter applications. The MOSFETs are rated for 1200V and 50A. Device characteristics were...Washington, DC, 2008. [5] Callanan, R. J., and Et Al. "Recent Progress in SiC DMOSFETs and JBS Diodes at Cree ", 34th Annual Conference of IEEE...1 -- 16 X 2 LCD Module LCD_ON, -- Power ON/OFF LCD_BLON, -- Back Light ON/OFF

  15. Ma'ii Washindoongoo Deeya [A Coyote Goes to Washington].

    Science.gov (United States)

    Dissemination and Assessment Center for Bilingual Education, Austin, TX.

    This children's reader in the Navajo language describes the experiences of a personified coyote as he leaves home to go on a business trip to Washington, D.C. It is designed for children in kindergarten through third grade in a bilingual education setting. (NCR)

  16. Tiger Team assessment of the Lawrence Berkeley Laboratory, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    1991-02-01

    This report documents the results of the Department of Energy's (DOE's) Tiger Team Assessment of the Lawrence Berkeley Laboratory (LBL) conducted from January 14 through February 15, 1991. The purpose of the assessment was to provide the Secretary of Energy with the status of environment, safety, and health (ES H) programs at LBL. The Tiger Team concluded that curtailment of cessation of any operations at LBL is not warranted. However, the number and breadth of findings and concerns from this assessment reflect a serious condition at this site. In spite of its late start, LBL has recently made progress in increasing ES H awareness at all staff levels and in identifying ES H deficiencies. Corrective action plans are inadequate, however, many compensatory actions are underway. Also, LBL does not have the technical expertise or training programs nor the tracking and followup to effectively direct and control sitewide guidance and oversight by DOE of ES H activities at LBL. As a result of these deficiencies, the Tiger Team has reservations about LBL's ability to implement effective actions in a timely manner and, thereby, achieve excellence in their ES H program. 4 figs., 24 tabs.

  17. Doubly fed machine review: agenda. Conference report, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    1982-09-01

    The visual aids presented at the doubly fed machine review are presented. The doubly fed machine is a generating system either for wind turbines or hydro systems. Conceptual design and trade-offs are included, as well as testing. (LEW)

  18. 147 between the holocaust museum in washington dc and ghana's

    African Journals Online (AJOL)

    HP-G61

    concerns trade relations, the middle passage and the African diaspora. A fifteen to twenty minutes film was commissioned from the famous Ghanaian filmmaker, Kwaw Ansah “in other to orient visitors to the themes of the exhibition.” The artifacts of the exhibition include archaeological materials, including nineteenth century ...

  19. Variable-Speed Screw Chiller, Sidney Yates Building, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Ostrouchov, George [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Adams, Mark B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howett, Daniel H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    This report captures the findings from an evaluation ORNL performed on a new chiller technology as part of GSA's Proving Ground Program. Note: Appendices B&C were removed from this report while the author looks for a way to insert them without consuming over 200MB of file size.

  20. 77 FR 25781 - Environmental Impact Statement; Washington, DC

    Science.gov (United States)

    2012-05-01

    .... Built over 100 years ago, the tunnel is nearing the end of its useful life and is subject to an ever.... Lawson, Division Administrator, District of Columbia Division, Federal Highway Administration. BILLING...

  1. The Capitol Experience in Washington, D.C.

    Science.gov (United States)

    Dilworth, R. Anne

    Designed for 11th grade U.S. history students, the teaching unit combines the history of the U.S. Capitol building and its Greek and Roman revival architecture to tell the story of the nation's government buildings. While the unit uses the U.S. Capitol, any other public building could be used, such as a state capitol, court house, or public…

  2. University of Washington

    Data.gov (United States)

    Federal Laboratory Consortium — The theme of the University of Washington based Center for Child Environmental Health Risks Research (CHC) is understanding the biochemical, molecular and exposure...

  3. Washington Tsunami Hazard Mitigation Program

    Science.gov (United States)

    Walsh, T. J.; Schelling, J.

    2012-12-01

    Washington State has participated in the National Tsunami Hazard Mitigation Program (NTHMP) since its inception in 1995. We have participated in the tsunami inundation hazard mapping, evacuation planning, education, and outreach efforts that generally characterize the NTHMP efforts. We have also investigated hazards of significant interest to the Pacific Northwest. The hazard from locally generated earthquakes on the Cascadia subduction zone, which threatens tsunami inundation in less than hour following a magnitude 9 earthquake, creates special problems for low-lying accretionary shoreforms in Washington, such as the spits of Long Beach and Ocean Shores, where high ground is not accessible within the limited time available for evacuation. To ameliorate this problem, we convened a panel of the Applied Technology Council to develop guidelines for construction of facilities for vertical evacuation from tsunamis, published as FEMA 646, now incorporated in the International Building Code as Appendix M. We followed this with a program called Project Safe Haven (http://www.facebook.com/ProjectSafeHaven) to site such facilities along the Washington coast in appropriate locations and appropriate designs to blend with the local communities, as chosen by the citizens. This has now been completed for the entire outer coast of Washington. In conjunction with this effort, we have evaluated the potential for earthquake-induced ground failures in and near tsunami hazard zones to help develop cost estimates for these structures and to establish appropriate tsunami evacuation routes and evacuation assembly areas that are likely to to be available after a major subduction zone earthquake. We intend to continue these geotechnical evaluations for all tsunami hazard zones in Washington.

  4. Study on the Control Algorithm of Two-Stage DC-DC Converter for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Changhao Piao

    2014-01-01

    Full Text Available The fast response, high efficiency, and good reliability are very important characteristics to electric vehicles (EVs dc/dc converters. Two-stage dc-dc converter is a kind of dc-dc topologies that can offer those characteristics to EVs. Presently, nonlinear control is an active area of research in the field of the control algorithm of dc-dc converters. However, very few papers research on two-stage converter for EVs. In this paper, a fixed switching frequency sliding mode (FSFSM controller and double-integral sliding mode (DISM controller for two-stage dc-dc converter are proposed. And a conventional linear control (lag is chosen as the comparison. The performances of the proposed FSFSM controller are compared with those obtained by the lag controller. In consequence, the satisfactory simulation and experiment results show that the FSFSM controller is capable of offering good large-signal operations with fast dynamical responses to the converter. At last, some other simulation results are presented to prove that the DISM controller is a promising method for the converter to eliminate the steady-state error.

  5. Laboratory manual for pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2015-01-01

    Designed to complement a range of power electronics study resources, this unique lab manual helps students to gain a deep understanding of the operation, modeling, analysis, design, and performance of pulse-width modulated (PWM) DC-DC power converters.  Exercises focus on three essential areas of power electronics: open-loop power stages; small-signal modeling, design of feedback loops and PWM DC-DC converter control schemes; and semiconductor devices such as silicon, silicon carbide and gallium nitride. Meeting the standards required by industrial employers, the lab manual combines program

  6. 1974 Washington timber harvest.

    Science.gov (United States)

    J.D. Jr. Lloyd

    1976-01-01

    The 1974 timber harvest of 6.88 billion board feet declined 933 million board feet (11.9 percent) below the record 1973 harvest. Decreases occurred in almost all owner groups. In western Washington the decline was 856 million board feet (13.0 percent). In eastern Washington the decline was 76 million board feet (6.3 percent).

  7. DC-to-DC switching converter

    Science.gov (United States)

    Cuk, Slobodan M. (Inventor); Middlebrook, Robert D. (Inventor)

    1980-01-01

    A dc-to-dc converter having nonpulsating input and output current uses two inductances, one in series with the input source, the other in series with the output load. An electrical energy transferring device with storage, namely storage capacitance, is used with suitable switching means between the inductances to DC level conversion. For isolation between the source and load, the capacitance may be divided into two capacitors coupled by a transformer, and for reducing ripple, the inductances may be coupled. With proper design of the coupling between the inductances, the current ripple can be reduced to zero at either the input or the output, or the reduction achievable in that way may be divided between the input and output.

  8. Site Selection, Acquisition, and Planning for Aquaculture in Dredged Material Containment Areas

    Science.gov (United States)

    1993-08-01

    advantage of containment area aquaculture over conventional aquaculture is that capital costs for initial construction incurred by an aquacul- turist may be...resources agencies Local health departments Geology and environmental science departments at local universities US Food and Drug Administration (FDA...plan," National Oceanic and Atmo- spheric Administration , Washington, DC. 82 References Hanftnan, D. T. (1987). "Shellfish culture: 1979-1986," Quick

  9. 75 FR 38943 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-30, DC...

    Science.gov (United States)

    2010-07-07

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-40, and DC-10-40F Airplanes AGENCY... propose to adopt a new airworthiness directive (AD) for certain Model DC-10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10- 40, and DC-10-40F airplanes. This proposed AD would require installing a support...

  10. 75 FR 63040 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-30, DC...

    Science.gov (United States)

    2010-10-14

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-40, and DC-10-40F Airplanes AGENCY... (b) None. Applicability (c) This AD applies to McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-40, and DC-10- 40F airplanes, certificated in any category...

  11. Washington County Crash Data

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Contains locations and information about every crash incident reported to the police in Washington County from 2011 to 2015. Fields include injury severity,...

  12. President George Washington: A Timeless Model of Great Leadership

    Science.gov (United States)

    2011-04-29

    illustrated in this paper. There are also many examples of this leadership quality throughout history but few ever reach the level that Washington...Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-01BB) Washington, DC...model of great leadership . N/A Sb. GRANT NUMBER N/A Sc. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) Sd. PROJECT NUMBER LCDR MatthewS. Jones, SC, USN

  13. Three new DC-to-DC Single-Switch Converters

    Directory of Open Access Journals (Sweden)

    Barry W. Williams

    2017-06-01

    Full Text Available This paper presents a new family of three previously unidentified dc-to-dc converters, buck, boost, and buck-boost voltage-transfer-function topologies, which offer advantageous transformer coupling features and low capacitor dc voltage stressing. The three single-switch, single-diode, converters offer the same features as basic dc-to-dc converters, such as the buck function with continuous output current and the boost function with continuous input current. Converter time-domain simulations and experimental results (including transformer coupling support and extol the dc-to-dc converter concepts and analysis presented.

  14. The Legacy of the Georgetown College Observatory (D.C.)

    Science.gov (United States)

    Caron, Laura; Maglieri, Grace; Seitzer, Patrick

    2018-01-01

    Founded in 1841 as part of a nascent worldwide network of Jesuit-run astronomical observatories, the Georgetown College Observatory of Georgetown University in Washington, D.C. has been home to more than 125 years of astronomical research, from Father Curley’s calculations of the latitude and longitude of D.C. to Father McNally’s award-winning solar eclipse photography. But the impact of the Georgetown astronomy program was not limited to the observatory itself: it reached much further, into the local community and schools, and into the lives of everyone involved. This was never more apparent than under the directorship of Father Francis J Heyden, S.J., who arrived at Georgetown after World War II and stayed for almost three decades. He started a graduate program with over 90 graduates, hosting student researchers from local high schools and colleges, teaching graduate and undergraduate astronomy courses, and speaking at schools in the area, all while simultaneously managing Georgetown’s student radio station and hosting astronomical conferences on campus. Father Heyden’s research focused mainly on solar eclipses for geodetic purposes and planetary spectroscopy. But perhaps even more than research, Father Heyden dedicated his time and energy to the astronomy students, the notable of which include Vera Rubin, John P. Hagen of Project Vanguard, and a generation of Jesuit astronomers including Martin McCarthy, George Coyne, and Richard Boyle. Following the closure of the astronomy department in 1972, Father Heyden returned to Manila, where he had begun his astronomical career, to become Chief of the Solar Division at the Manila Observatory. His dedication to his work and to students serves as an inspiration for academic researchers across fields, and for the Georgetown University Astronomical Society, which, even in the absence of a formal astronomy program at Georgetown, continues his work in education and outreach today. In 1987, almost 150 years after its

  15. Three new DC-to-DC Single-Switch Converters

    OpenAIRE

    Barry W. Williams; Mona Fouad Moussa

    2017-01-01

    This paper presents a new family of three previously unidentified dc-to-dc converters, buck, boost, and buck-boost voltage-transfer-function topologies, which offer advantageous transformer coupling features and low capacitor dc voltage stressing. The three single-switch, single-diode, converters offer the same features as basic dc-to-dc converters, such as the buck function with continuous output current and the boost function with continuous input current. Converter time-domain simulations ...

  16. 75 FR 68246 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

    Science.gov (United States)

    2010-11-05

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F... to supersede an existing airworthiness directive (AD) that applies to all Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, MD-10- 10F, MD-10-30F, MD-11...

  17. 75 FR 20790 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

    Science.gov (United States)

    2010-04-21

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F... (AD) for certain Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC- 10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, MD-11, and MD-11F airplanes. This proposed AD would require...

  18. 75 FR 23571 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

    Science.gov (United States)

    2010-05-04

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F.... ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for certain Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD...

  19. 75 FR 60602 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

    Science.gov (United States)

    2010-10-01

    ... Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F.... ACTION: Final rule. SUMMARY: We are adopting a new airworthiness directive (AD) for certain Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD...

  20. Three-port DC-DC converter with new integrated transformer for DC Distribution Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2014-01-01

    A new integrated transformer for three-port dc-dc converter is proposed to overcome the power coupling effect existed in some known multiple inputs dc-dc converters. Orthogonal primary windings arrangement and in series connection of diagonal secondary Windings enables a fully power decoupling...

  1. Timber resource statistics for eastern Washington, 1995.

    Science.gov (United States)

    Neil McKay; Patricia M. Bassett; Colin D. MacLean

    1995-01-01

    This report summarizes a 1990-91 timber resource inventory of Washington east of the crest of the Cascade Range. The inventory was conducted on all private and public lands except National Forests. Timber resource statistics from National Forest inventories also are presented. Detailed tables provide estimates of forest area, timber volume, growth, mortality, and...

  2. Timber resource statistics for western Washington.

    Science.gov (United States)

    Coffin D. MacLean; Patricia M. Bassett; Glenn. Yeary

    1992-01-01

    This report summarizes a 1988-90 timber resource inventory of 19 counties in western Washington: Clallam, Clark, Cowlitz, Grays Harbor, Island, Jefferson, King, Kitsap, Lewis, Mason, Pacific, Pierce, San Juan, Skagit, Skamania, Snohomish, Thurston, Wahkiakum, and Whatcom. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  3. More than 6,500 Buildings Face Off in EPAs Sixth Annual Energy Star Battle of the Buildings Competition/U.S. commercial buildings in all 50 states and Washington, D.C. race to save energy, water and reduce greenhouse gas emissions

    Science.gov (United States)

    WASHINGTON - Today, the U.S. Environmental Protection Agency (EPA) launched the 2015 Energy Star Battle of the Buildings. Nationwide, more than 6,500 buildings and 125 teams are competing to reduce their energy and water use. In support of President

  4. Overview of Multi-DC-Bus Solutions for DC Microgrids

    DEFF Research Database (Denmark)

    Ricchiuto, D.; Mastromauro, R.A.; Liserre, Marco

    2013-01-01

    DC Microgrids have recently received a lot of attention in the last years due to high penetration of renewable energy sources as well as distributed energy storage systems. In the future DC microgrids could be preferable respect to AC microgrids in terms of redundancy since multi-DC-Bus solutions...... could provide a continuative power supply to the loads. An overview of Multi-DC-Bus solutions is presented in this paper. The performances are compared on the basis of possible DC microgrid configurations, redundancy, different DC voltage levels....

  5. Habitat fragmentation and the persistence of lynx populations in Washington state

    Science.gov (United States)

    Gary M Koehler; Benjamin T. Maletzke; Jeff A. Von Kienast; Keith B. Aubry; Robert B. Wielgus; Robert H. Naney

    2008-01-01

    Lynx (Lynx canadensis) occur in the northern counties of Washington state, USA; however, current distribution and status of lynx in Washington are poorly understood. During winters 2002-2004 we snow-tracked lynx for 155 km within a 211-km2 area in northern Washington, to develop a model of lynx-habitat relationships that we...

  6. Forest industries of eastern Washington.

    Science.gov (United States)

    Brian R. Wall; Donald R. Gedney; Robert B. Forster

    1966-01-01

    A sawmill, built in 1872, marked the beginning of the forest industry in eastern Washington -- almost half a century after the emergence of the lumber industry in western Washington. Since then, this industry has increased in importance to eastern Washington's economy, now furnishing about one-fifth of the total manufacturing employment and wages paid—in...

  7. DC arc weld starter

    Science.gov (United States)

    Campiotti, Richard H.; Hopwood, James E.

    1990-01-01

    A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

  8. Timber resource statistics for the Olympic Peninsula, Washington.

    Science.gov (United States)

    Patricia M. Bassett; Daniel D. Oswald

    1961-01-01

    This report summarizes a 1978-79 timber resource inventory of five counties in the Olympic Peninsula of Washington: Clallam, Grays Harbor, Jefferson, Mason, and Thurston. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  9. Early Oscillation Detection for DC/DC Converter Fault Diagnosis

    Science.gov (United States)

    Wang, Bright L.

    2011-01-01

    The electrical power system of a spacecraft plays a very critical role for space mission success. Such a modern power system may contain numerous hybrid DC/DC converters both inside the power system electronics (PSE) units and onboard most of the flight electronics modules. One of the faulty conditions for DC/DC converter that poses serious threats to mission safety is the random occurrence of oscillation related to inherent instability characteristics of the DC/DC converters and design deficiency of the power systems. To ensure the highest reliability of the power system, oscillations in any form shall be promptly detected during part level testing, system integration tests, flight health monitoring, and on-board fault diagnosis. The popular gain/phase margin analysis method is capable of predicting stability levels of DC/DC converters, but it is limited only to verification of designs and to part-level testing on some of the models. This method has to inject noise signals into the control loop circuitry as required, thus, interrupts the DC/DC converter's normal operation and increases risks of degrading and damaging the flight unit. A novel technique to detect oscillations at early stage for flight hybrid DC/DC converters was developed.

  10. BASEMAP, LEWIS COUNTY AND INCORPORATED AREAS, WASHINGTON

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — FEMA Framework Basemap datasets comprise six of the seven FGDC themes of geospatial data that are used by most GIS applications (Note: the seventh framework theme,...

  11. 75 FR 6160 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

    Science.gov (United States)

    2010-02-08

    ... Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, MD-10-10F, MD-10-30F, MD-11, and MD-11F Airplanes AGENCY: Federal Aviation... airworthiness directive (AD) for certain Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC- 10A and...

  12. Business leaders bring their clout to Washington.

    Science.gov (United States)

    Burke, M

    1990-04-20

    Big business has always been opposed to government interference in its affairs. But now, besieged by the high cost--increasing at an annual rate of 20 to 30 percent--of health benefits for employees, their families, and retirees, a significant number of major corporate executives are seeking greater government involvement in finding a solution to the problem. Interest in health care policy decisions is so high that business leaders are participating in special health care commissions as members or by providing testimony. Some corporations even send company advocates to Washington, DC, to track and influence health care policymaking. What exactly do these corporate leaders want? They are not all in agreement about the degree of government involvement that is necessary or desirable. Nevertheless, they do have strong opinions about delivery of health care at the local level.

  13. Design of a kilowatt DC-DC converter

    Directory of Open Access Journals (Sweden)

    Liu Hongxing

    2017-01-01

    Full Text Available In view of the low power of traditional DC-DC converters, a DC-DC converter with a kilowatt power is designed. The input signal's frequency is 1 kHz and the duty cycle is 5%. The PWM signal controls the high-speed conduction or cut-off of the switch tube. The input DC voltage is 36V, and the output voltage is twice as high as the input voltage. The output power is greater than 1 KW; the circuit conversion efficiency is 87.21%.

  14. Conservation Lands and Preserves, Agricultural, Rural Legacy Easements & Area Boundary: The most common use is for the interpretation of land protected with the Rural Legacy program. The Rural Legacy Area protects farmland, forests and Civil War sites, within view of the Washington Monument State Park,, Published in 2008, 1:7200 (1in=600ft) scale, Washington County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Conservation Lands and Preserves, Agricultural dataset current as of 2008. Rural Legacy Easements & Area Boundary: The most common use is for the interpretation...

  15. DC micro-grids

    OpenAIRE

    Mia, Gredelj

    2014-01-01

    The conventional electrical system in place today sees our electrical devices powered by AC mains. But as renewable technologies such as solar photovoltaic and wind power become more prevalent at a household level, DC micro-grids could be a cheaper and more efficient alternative. New lighting devices (LED) can reduce the electricity consumption substantially. Two alternatives are envisioned in this paper: A stand-alone alternative in which there is no grid connection, that would require local...

  16. SMALL-SCALE MELTER TESTING WITH LAW SIMULANTS TO ASSESS THE IMPACT OF HIGHER TEMPERATURE MELTER OPERATIONS - Final Report, VSL-04R49801-1, Rev. 0, 2/13/03, Vitreous State Laboratory, The Catholic University of America, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    KRUGER AA; MATLACK KS

    2012-02-07

    About 50 million gallons of high-level mixed waste is currently in storage in underground tanks at The United States Department of Energy's (DOE's) Hanford site in the State of Washington. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) will provide DOE's Office of River Protection (ORP) with a means of treating this waste by vitrification for subsequent disposal. The tank waste will be separated into low- and high-activity fractions, which will then be vitrified respectively into Immobilized Low Activity Waste (ILAW) and Immobilized High Level Waste (IHLW) products. The ILAW product will be disposed of in an engineered facility on the Hanford site while the IHL W product will be directed to the national deep geological disposal facility for high-level nuclear waste. The ILAW and IHLW products must meet a variety of requirements with respect to protection of the environment before they can be accepted for disposal. The Office of River Protection is currently examining options to optimize the Low Activity Waste (LAW) facility and the LAW glass waste form. One option under evaluation is to enhance the waste processing rate of the vitrification plant currently under construction. It is likely that the capacity of the LAW vitrification plant can be increased incrementally by implementation of a variety of low-risk, high-probability changes, either separately or in combination. These changes include: (1) Operating at the higher processing rates demonstrated at the LAW Pilot Melter; (2) Increasing the glass pool surface area within the existing external melter envelope; (3) Increasing plant availability; (4) Increasing the glass waste loading; (5) Removing sulfate from the LAW stream; (6) Operating the melter at slightly higher temperature; (7) Installing the third LAW melter into the WTP plant; and (8) Other smaller impact changes. The tests describes in this report utilized blended feed (glass formers plus waste simulant) prepared by

  17. 77 FR 46118 - Notice of Inventory Completion: Department of the Interior, Bureau of Indian Affairs, Washington...

    Science.gov (United States)

    2012-08-02

    ..., Washington, DC, and Logan Museum of Anthropology, Beloit College, Beloit, WI AGENCY: National Park Service... Museum of Anthropology, Beloit College, have completed an inventory of human remains, in consultation with the appropriate Indian tribe, and have determined that there is a cultural affiliation between the...

  18. Dynamic Evolution Control for Fuel Cell DC-DC Converter

    Directory of Open Access Journals (Sweden)

    Ahmad Saudi Samosir

    2011-04-01

    Full Text Available Fuel cells are new alternative energy resource that has a great promise for distributed generation and electric vehicle application. However, fuel cells have a slow response due to their slow internal electromechanical and thermodynamic response. To optimize the fuel cell system performance, a fuel cell DC-DC converter with an appropriate controller which can regulate the power flow and automatically adjust the converter output voltage is needed. This paper proposes a new control technique for fuel cell DC-DC power converter. Design of the proposed control method for fuel cell DC-DC power converter is provided. A new approach for converter controllers synthesis based on dynamic evolution control theory is presented. In this paper, synthesis example of boost DC-DC converter is discussed. Performance of the proposed dynamic evolution control under step load variation condition is simulated under Matlab-Simulink environment. Simulation results show that the proposed techniques are capable for controlling fuel cell DC-DC converter.

  19. A new optimum topology switching dc-to-dc converter

    Science.gov (United States)

    Cuk, S.; Middlebrook, R. D.

    1977-01-01

    A novel switching dc-to-dc converter is presented, which has the same general conversion property (increase or decrease of the input dc voltage) as does the conventional buck-boost converter, and which offers through its new optimum topology higher efficiency, lower output voltage ripple, reduced EMI, smaller size and weight, and excellent dynamic response. One of its most significant advantages is that both input and output current are not pulsating but are continuous (essentially dc with small superimposed switching current ripple), thus resulting in a close approximation to the ideal physically nonrealizable dc-to-dc transformer. The converter retains the simplest possible structure with the minimum number of components which, when interconnected in its optimum topology, yield the maximum performance.

  20. PENGGUNAAN FUZZY LOGIC UNTUK KONTROL PARALLEL CONVERTER DC-DC

    Directory of Open Access Journals (Sweden)

    Bambang Prio Hartono

    2012-09-01

    Full Text Available Abstract: Using system fuzzy logic as control  technology have been used on low load dc-dc converter with combined parallel compiled  dc-dc converter can  obtain big load.   With existence of differrence of component parameter and each parallel compiled converter can obtained different current  and voltage output.  Function of controller  for to do adjustment, so that current which is applied  to  load by each converter  can be obtained  difference error as small as possible or same. The object of research is developing design of large signal dc-dc converter which is  combined with using  FLC so that  obtain  better performance.  To get better performance have been made plant model and simulation with CDE method.  The more systematic  system and design is needed to overcome bigger load  on dc-dc converter, so that parallel  compiled current master slave control system on dc-dc converter with using fuzzy logic  controller is used. Result of  research showed that error or difference of  current  which is applied to load can handled by fuzzy logic  controller.  Technic of current and voltage controller co to do adjustment current and voltage distribution  equally to load.  Distribution of iL1,iL2 and  output voltage Vo on dc-dc  converter with load 2,25 until  7,875 and voltage  100  until 120 volt,  load current beetwen  12 until 48, % relatif  error  Vo  0,4% until  0,9%.

  1. Direct Sensitivity Analysis of the DC-to-DC Converters

    Directory of Open Access Journals (Sweden)

    Elena Niculescu

    2009-05-01

    Full Text Available The mathematical principle of the directsensitivity analysis of the dynamic systems and itsapplication to the DC-to-DC PWM converters arepresented. The model of the dynamic system associatedto the PWM Sepic converter with parasitic includedand continuous conduction mode (CCM, and coupledinductors was used in this study. The modelling of theconverter and the state sensitivity analysis with respectto some parameters of the converter have beenperformed with MATLAB environment. The algorithmcarried out for computing the state sensitivity functionsof converter can be applied to other configurations ofDC-to-DC PWM converters, for the two operatingmodes (CCM and DCM, with parasitic included andwith coupled or separate inductors, regardless ofsystem order.

  2. Trends of DC Power Technologies and their Applications

    Science.gov (United States)

    Hirose, Keiichi

    Renewable energy resources such as photovoltaic panels and wind turbines have been increasing rapidly to prevent global warming. The number of energy storage systems and many types of batteries is also growing to keep supply and demand balance in local areas. Interfaces of these facilities are direct current (DC). Most of modern electrical appliances also use DC power inside them. Therefore, DC power technologies with some features are expected to meet requirements for new electrical power systems, for example smartgrids, microgrids, and other electrical applications. In recent years, DC power applications in data centers, commercial buildings, and dwellings have been developed in Japan, the U.S. European countries, and so on. At the same time, international standardization activities had started. This paper describes trends of DC power technologies and their applications.

  3. Washington State Biofuels Industry Development

    Energy Technology Data Exchange (ETDEWEB)

    Gustafson, Richard [Univ. of Washington, Seattle, WA (United States)

    2017-04-09

    The funding from this research grant enabled us to design, renovate, and equip laboratories to support University of Washington biofuels research program. The research that is being done with the equipment from this grant will facilitate the establishment of a biofuels industry in the Pacific Northwest and enable the University of Washington to launch a substantial biofuels and bio-based product research program.

  4. DC Distribution Systems and Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Anvari-Moghaddam, Amjad; Quintero, Juan Carlos Vasquez

    2017-01-01

    A qualitative overview of different hardware topologies and control systems for DC MGs has been presented in this chapter. Some challenges and design considerations of DC protections systems have also been discussed. Finally, applications of DC MGs in emerging smart grid applications have been su...... in different industries and gradually lead to new ways of rethinking of the future power distribution philosophies, especially with the emergence of SSTs. Research in DC systems, especially in the power electronics-based technologies will be highly attractive in the future....

  5. A Robust Fuzzy Sliding Mode Controller Synthesis Applied on Boost DC-DC Converter Power Supply for Electric Vehicle Propulsion System

    Directory of Open Access Journals (Sweden)

    Boumediène Allaoua

    2013-01-01

    Full Text Available The development of electric vehicles power electronics system control comprising of DC-AC inverters and DC-DC converters takes a great interest of researchers in the modern industry. A DC-AC inverter supplies the high power electric vehicle motors torques of the propulsion system and utility loads, whereas a DC-DC converter supplies conventional low-power, low-voltage loads. However, the need for high power bidirectional DC-DC converters in future electric vehicles has led to the development of many new topologies of DC-DC converters. Nonlinear control of power converters is an active area of research in the fields of power electronics. This paper focuses on a fuzzy sliding mode strategy (FSMS as a control strategy for boost DC-DC converter power supply for electric vehicle. The proposed fuzzy controller specifies changes in the control signal based on the surface and the surface change knowledge to satisfy the sliding mode stability and attraction conditions. The performances of the proposed fuzzy sliding controller are compared to those obtained by a classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variation of the load resistance and the input voltage of the studied converter.

  6. SCM Handbooks for dc-to-dc Converters

    Science.gov (United States)

    Lee, F.; Mohmoud, M.; Yu, Y.

    1984-01-01

    Two documents aid in design of control modules for dc-to-dc converters. Features of SCM include: Adaptive stability, power component stress limiting, implementation of various control laws, unified design approach. Analysis and quidelines contained in handbooks enable engineer to design SCM circuit and confidently predict resulting overall performance.

  7. Dc-To-Dc Converter Uses Reverse Conduction Of MOSFET's

    Science.gov (United States)

    Gruber, Robert P.; Gott, Robert W.

    1991-01-01

    In modified high-power, phase-controlled, full-bridge, pulse-width-modulated dc-to-dc converters, switching devices power metal oxide/semiconductor field-effect transistors (MOSFET's). Decreases dissipation of power during switching by eliminating approximately 0.7-V forward voltage drop in anti-parallel diodes. Energy-conversion efficiency increased.

  8. Historical Material Analysis of DC745U Pressure Pads

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz-Acosta, Denisse [Los Alamos National Laboratory

    2012-07-30

    As part of the Enhance Surveillance mission, it is the goal to provide suitable lifetime assessment of stockpile materials. This report is an accumulation of historical publication on the DC745U material and their findings. It is the intention that the B61 LEP program uses this collection of data to further develop their understanding and potential areas of study. DC745U is a commercially available silicone elastomer consisting of dimethyl, methyl-phenyl, and methyl-vinyl siloxane repeat units. Originally, this material was manufactured by Dow Corning as Silastic{reg_sign} DC745U at their manufacturing facility in Kendallville, IN. Recently, Dow Corning shifted this material to the Xiameter{reg_sign} brand product line. Currently, DC745U is available through Xiameter{reg_sign} or Dow Corning's distributor R. D. Abbott Company. DC745U is cured using 0.5 wt% vinyl-specific peroxide curing agent known as Luperox 101 or Varox DBPH-50. This silicone elastomer is used in numerous parts, including two major components (outer pressure pads and aft cap support) in the W80 and as pressure pads on the B61. DC745U is a proprietary formulation, thus Dow Corning provides limited information on its composition and properties. Based on past experience with Dow Corning, DC745U is at risk of formulation changes without notification to the costumer. A formulation change for DC745U may have a significant impact because the network structure is a key variable in determining material properties. The purpose of this report is to provide an overview of historical DC745U studies and identify gaps that need to be addressed in future work. Some of the previous studies include the following: 1. Spectroscopic characterization of raw gum stock. 2. Spectroscopic, thermal, and mechanical studies on cured DC745U. 3. Nuclear Magnetic Resonance (NMR) and solvent swelling studies on DC745U with different crosslink densities. 4. NMR, solvent swelling, thermal, and mechanical studies on thermally

  9. Early Oscillation Detection Technique for Hybrid DC/DC Converters

    Science.gov (United States)

    Wang, Bright L.

    2011-01-01

    Oscillation or instability is a situation that must be avoided for reliable hybrid DC/DC converters. A real-time electronics measurement technique was developed to detect catastrophic oscillations at early stages for hybrid DC/DC converters. It is capable of identifying low-level oscillation and determining the degree of the oscillation at a unique frequency for every individual model of the converters without disturbing their normal operations. This technique is specially developed for space-used hybrid DC/DC converters, but it is also suitable for most of commercial and military switching-mode power supplies. This is a weak-electronic-signal detection technique to detect hybrid DC/DC converter oscillation presented as a specific noise signal at power input pins. It is based on principles of feedback control loop oscillation and RF signal modulations, and is realized by using signal power spectral analysis. On the power spectrum, a channel power amplitude at characteristic frequency (CPcf) and a channel power amplitude at switching frequency (CPsw) are chosen as oscillation level indicators. If the converter is stable, the CPcf is a very small pulse and the CPsw is a larger, clear, single pulse. At early stage of oscillation, the CPcf increases to a certain level and the CPsw shows a small pair of sideband pulses around it. If the converter oscillates, the CPcf reaches to a higher level and the CPsw shows more high-level sideband pulses. A comprehensive stability index (CSI) is adopted as a quantitative measure to accurately assign a degree of stability to a specific DC/DC converter. The CSI is a ratio of normal and abnormal power spectral density, and can be calculated using specified and measured CPcf and CPsw data. The novel and unique feature of this technique is the use of power channel amplitudes at characteristic frequency and switching frequency to evaluate stability and identify oscillations at an early stage without interfering with a DC/DC converter s

  10. A DC Transformer

    Science.gov (United States)

    Youngquist, Robert C.; Ihlefeld, Curtis M.; Starr, Stanley O.

    2013-01-01

    A component level dc transformer is described in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both de devices, such that the output voltage of a de power supply can be stepped up (or down) with a corresponding step down (or up) in current. The basic theory for this device is developed, performance predictions are made, and the results from a small prototype are presented. Based on demonstrated technology in the literature, this de transformer should be scalable to low megawatt levels, but it is more suited to high current than high voltage applications. Significant development would be required before it could achieve the kilovolt levels needed for de power transmission.

  11. Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex, multiple-output, DC-DC converter systems can be configured through use of only 2 standard product hybrid DC-DC...

  12. Triple voltage dc-to-dc converter and method

    Science.gov (United States)

    Su, Gui-Jia

    2008-08-05

    A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

  13. Bi-Directional DC-DC Converter for PHEV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Abas Goodarzi

    2011-01-31

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  14. TERRAIN, Kittitas, Washington

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Kittitas AOI consists of two areas. These areas were to be collected to the 'highest' accuracy requirement. Ground Control is collected throughout the AOI for...

  15. Forest statistics for northeast Washington.

    Science.gov (United States)

    John W. Hazard

    1963-01-01

    This publication summarizes the results of the third inventory of six northeast Washington counties: Ferry, Lincoln, Pend Oreille, Spokane, Stevens, and Whitman. The collection of field data was made during the years 1957 to 1961 in three separate inventory projects.

  16. Universality of DC electrical conductivity from holography

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Xian-Hui, E-mail: gexh@shu.edu.cn [Shanghai Key Laboratory of High Temperature Superconductors, Department of Physics, Shanghai University, Shanghai, 200444 (China); Department of Physics, University of California, San Diego, CA92122 (United States); Sin, Sang-Jin, E-mail: sjsin@hangyang.ac.kr [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Wu, Shao-Feng, E-mail: sfwu@shu.edu.cn [Department of Physics, Shanghai University, Shanghai, 200444 (China)

    2017-04-10

    We propose a universal formula of dc electrical conductivity in rotational- and translational-symmetries breaking systems via the holographic duality. This formula states that the ratio of the determinant of the dc electrical conductivities along any spatial directions to the black hole area density in zero-charge limit has a universal value. As explicit illustrations, we give several examples elucidating the validation of this formula: We construct an anisotropic black brane solution, which yields linear in temperature for the in-plane resistivity and insulating behavior for the out-of-plane resistivity; We also construct a spatially isotropic black brane solution that both the linear-T and quadratic-T contributions to the resistivity can be realized.

  17. 12 CFR 4.4 - Washington office.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Washington office. 4.4 Section 4.4 Banks and... EXAMINERS Organization and Functions § 4.4 Washington office. The Washington office of the OCC is the main office and headquarters of the OCC. The Washington office directs OCC policy, oversees OCC operations...

  18. Step-Up DC-DC Power Converter

    DEFF Research Database (Denmark)

    2015-01-01

    capacitor coupled between the positive and negative input terminals and the secondary side circuit comprises an output capacitor chargeable to a converter output voltage between a first positive electrode and a second negative electrode. A switched energy storage network is configured for alternatingly...... being charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier in accordance with a switch control signal to produce the converter output voltage. The step-up DC-DC power converter comprises an electrical short-circuit connection across the galvanic......The present invention relates to a step-up DC-DC power converter which comprises a primary side circuit and a secondary side circuit coupled through a galvanic isolation barrier. The primary side circuit comprises a positive and a negative input terminal for receipt of an input voltage and an input...

  19. Active pre-filters for dc/dc Boost regulators

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Ramos-Paja

    2014-05-01

    Full Text Available This paper proposes an active pre-filter to mitigate the current harmonics generated by classical dc/dc Boost regulators, which generate current ripples proportional to the duty cycle. Therefore, high output voltage conditions, i.e., high voltage conversion ratios, produce high current harmonics that must be filtered to avoid damage or source losses. Traditionally, these current components are filtered using electrolytic capacitors, which introduce reliability problems because of their high failure rate. The solution introduced in this paper instead uses a dc/dc converter based on the parallel connection of the Boost canonical cells to filter the current ripples generated by the Boost regulator, improving the system reliability. This solution provides the additional benefits of improving the overall efficiency and the voltage conversion ratio. Finally, the solution is validated with simulations and experimental results.

  20. Fuzzy Control of DC-DC Converters with Input Constraint

    Directory of Open Access Journals (Sweden)

    D. Saifia

    2012-01-01

    Full Text Available This paper proposes a method for designing fuzzy control of DC-DC converters under actuator saturation. Because linear control design methods do not take into account the nonlinearity of the system, a T-S fuzzy model and a controller design approach is used. The designed control not only handles the external disturbance but also the saturation of duty cycle. The input constraint is first transformed into a symmetric saturation which is represented by a polytopic model. Stabilization conditions for the state feedback system of DC-DC converters under actuator saturation are established using the Lyapunov approach. The proposed method has been compared and verified with a simulation example.

  1. Decentralized Interleaving of Paralleled Dc-Dc Buck Converters

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brian B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rodriguez, Miguel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sinha, Mohit [University of Minnesota; Dhople, Sairaj [University of Minnesota; Poon, Jason [University of California at Berkeley

    2017-08-21

    We present a decentralized control strategy that yields switch interleaving among parallel-connected dc-dc buck converters. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform and no communication between different controllers is needed. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work presents the first fully decentralized strategy for switch interleaving in paralleled dc-dc buck converters.

  2. Decentralized Interleaving of Paralleled Dc-Dc Buck Converters: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brian B [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rodriguez, Miguel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sinha, Mohit [University of Minnesota; Dhople, Sairaj [University of Minnesota; Poon, Jason [University of California at Berkeley

    2017-09-01

    We present a decentralized control strategy that yields switch interleaving among parallel connected dc-dc buck converters without communication. The proposed method is based on the digital implementation of the dynamics of a nonlinear oscillator circuit as the controller. Each controller is fully decentralized, i.e., it only requires the locally measured output current to synthesize the pulse width modulation (PWM) carrier waveform. By virtue of the intrinsic electrical coupling between converters, the nonlinear oscillator-based controllers converge to an interleaved state with uniform phase-spacing across PWM carriers. To the knowledge of the authors, this work represents the first fully decentralized strategy for switch interleaving of paralleled dc-dc buck converters.

  3. RESONANT STEP-DOWN DC-DC POWER CONVERTERS

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a resonant step-down DC-DC power converter which comprises a primary side circuit and a secondary side circuit coupled through a galvanic isolation barrier. The primary side circuit comprises a positive and a negative input terminal for receipt of an input voltage...... charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier by a semiconductor switch arrangement in accordance with a switch control signal to produce the converter output voltage. The resonant step-down DC-DC power converter comprises an electrical short......-circuit connection across the galvanic isolation barrier connecting, in a first case, the second negative electrode of the output capacitor to the positive input terminal of the primary side circuit or, in a second case, connecting the second positive electrode of the output capacitor to the negative input terminal...

  4. DC-10 winglet flight evaluation

    Science.gov (United States)

    Taylor, A. B.

    1983-01-01

    Results of a flight evaluation of winglets on a DC-10 Series 10 aircraft are presented. For sensitive areas of comparison, effects of winglets were determined back-to-back with and without winglets. Basic and reduced-span winglet configurations were tested. After initial encounter with low-speed buffet, a number of acceptable configurations were developed. For maximum drag reduction at both cruise and low speeds, lower winglets were required, having leading edge devices on upper and lower winglets for the latter regime. The cruise benefits were enhanced by adding outboard aileron droop to the reduced-span winglet aircraft. Winglets had no significant impact on stall speeds, high-speed buffet boundary, and stability and control. Flutter test results agreed with predictions and ground vibration data. Flight loads measurement, provided in a concurrent program, also agreed with predictions. It was estimated that a production version of the aircraft, using the reduced-span winglet and aileron droop, would yield a 3-percent reduction in fuel burned with capacity payload. This range was 2% greater than with winglets. A 5% reduction in takeoff distance at maximum takeoff weight would also result.

  5. DC-Compensated Current Transformer.

    Science.gov (United States)

    Ripka, Pavel; Draxler, Karel; Styblíková, Renata

    2016-01-20

    Instrument current transformers (CTs) measure AC currents. The DC component in the measured current can saturate the transformer and cause gross error. We use fluxgate detection and digital feedback compensation of the DC flux to suppress the overall error to 0.15%. This concept can be used not only for high-end CTs with a nanocrystalline core, but it also works for low-cost CTs with FeSi cores. The method described here allows simultaneous measurements of the DC current component.

  6. DC injection into low voltage AC networks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report summarises the results of a study investigating the impact of levels of injected DC current injections on a low voltage AC distribution network systems in order to recommend acceptable limits of DC from microgeneration. Relevant literature is reviewed, and the impact of DC levels in distribution transformers, transformer modelling, and instrumental transformers are discussed. The impact of DC in residual current devices (RCD) and in domestic electricity watt hour meters is examined along with DC enhanced corrosion, corrosion failure, and the measurement of DC current injection. Sources of DC injection outlined include DC from computer power supplies, network faults, geomagnetic phenomena, lighting circuits/dimmers, and embedded generators.

  7. Digital Control Technologies for Modular DC-DC Converters

    Science.gov (United States)

    Button, Robert M.; Kascak, Peter E.; Lebron-Velilla, Ramon

    2002-01-01

    Recent trends in aerospace Power Management and Distribution (PMAD) systems focus on using commercial off-the-shelf (COTS) components as standard building blocks. This move to more modular designs has been driven by a desire to reduce costs and development times, but is also due to the impressive power density and efficiency numbers achieved by today's commercial DC-DC converters. However, the PMAD designer quickly learns of the hidden "costs" of using COTS converters. The most significant cost is the required addition of external input filters to meet strict electromagnetic interference (MIAMI) requirements for space systems. In fact, the high power density numbers achieved by the commercial manufacturers are greatly due to the lack of necessary input filters included in the COTS module. The NASA Glenn Research Center is currently pursuing a digital control technology that addresses this problem with modular DC-DC converters. This paper presents the digital control technologies that have been developed to greatly reduce the input filter requirements for paralleled, modular DC-DC converters. Initial test result show that the input filter's inductor size was reduced by 75 percent, and the capacitor size was reduced by 94 percent while maintaining the same power quality specifications.

  8. Isolated step-down DC -DC converter for electric vehicles

    Science.gov (United States)

    Kukovinets, O. V.; Sidorov, K. M.; Yutt, V. E.

    2018-02-01

    Modern motor-vehicle industrial sector is moving rapidly now towards the electricity-driving cars production, improving their range and efficiency of components, and in particular the step-down DC/DC converter to supply the onboard circuit 12/24V of electric vehicle from the high-voltage battery. The purpose of this article - to identify the best circuitry topology to design an advanced step-down DC/DC converters with the smallest mass, volume, highest efficiency and power. And this will have a positive effect on driving distance of electric vehicle (EV). On the basis of computational research of existing and implemented circuit topologies of step-down DC/DC converters (serial resonant converter, full bridge with phase-shifting converter, LLC resonant converter) a comprehensive analysis was carried out on the following characteristics: specific volume, specific weight, power, efficiency. The data obtained was the basis for the best technical option - LLC resonant converter. The results can serve as a guide material in the process of components design of the traction equipment for electric vehicles, providing for the best technical solutions in the design and manufacturing of converting equipment, self-contained power supply systems and advanced driver assistance systems.

  9. DC Microgrids – Part I

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Lu, Xiaonan; Quintero, Juan Carlos Vasquez

    2016-01-01

    This paper presents a review of control strategies, stability analysis and stabilization techniques for DC microgrids (MGs). Overall control is systematically classified into local and coordinated control levels according to respective functionalities in each level. As opposed to local control...

  10. Linking DC together with TRSL

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Yong, X.

    2000-01-01

    Duration Calculus (DC) is an interval-based real-time logic, which can be used in capturing and eliciting users' real-time requirements. The Timed RAISE Specification Language (TRSL) is an extension of the RAISE Specification Language with real-time features. This paper links DC and TRSL together...... approach for linking state-based real-time logics together with event-based, timed process algebra languages....

  11. Test plan and preliminary report of airborne electromagentic environment survey over USA urban areas 0.4 to 18.0 GHz

    Science.gov (United States)

    Taylor, R. E.; Hill, J. S.

    1975-01-01

    An airborne electromagnetic environment survey is described of five urban areas where terrestrially-generated radio-frequency interference was measured over the frequency range from 0.4 to 18.0 GHz. A chartered Cessna 402 aircraft contained necessary measurement test equipment, including the receiving antennas mounted beneath the fuselage. Urban areas including Washington, D.C.; Baltimore, MD; Philadelphia, PA; New York, NY; Chicago, ILL; and Palestine, TX were surveyed. A flight test plan and preliminary test results for the 0.4 to 1.4 GHz frequency range, are included; a final test report describes more detailed results.

  12. Booker T. Washington's Educational Contributions to Contemporary Practices of Sustainable Development

    Science.gov (United States)

    Grant, Brett G.

    2014-01-01

    This article discusses Booker T. Washington's educational contributions to contemporary practices of sustainable development. In particular, the article looks at Washington's contributions in the areas of economic sustainability and entrepreneurship, character development, and aesthetics. As states continue to contemplate and evaluate the value of…

  13. The Impact of Interstate Migration on Human Capital Development in Washington

    Science.gov (United States)

    Spaulding, Randy

    2010-01-01

    Washington State is a leader in the innovation economy largely due to the combination of aerospace, software, and biomedical industries centered in the greater Seattle area; and, the state's high level of international trade. Despite Washington's national ranking, the state is overly reliant on importing educated workers from other states and…

  14. Atmel Microcontroller Based Soft Switched PWM ZVS Full Bridge DC to DC Converter

    Directory of Open Access Journals (Sweden)

    DEEPAK KUMAR NAYAK

    2010-12-01

    Full Text Available This paper deals with the simulation and implementation of soft switched PWM ZVS full bridge DC to DC converter. The 48V DC is efficiently reduced to 12V DC using a DC to DC converter. This converter has advantages like reduced switching losses, stresses and EMI. Input DC is converted into high frequency AC and it is stepped down to 12V level. Later it is rectified using a full wave rectifier. Laboratory model of microcontroller based DC to DC converter is fabricated and tested. The experimental results are compared with the simulation results.

  15. Very High Frequency Half Bridge DC/DC Converter

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...... components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED...

  16. A SOFT SWITCHED INTERLEAVED HIGH GAIN DC-DC CONVERTER

    Directory of Open Access Journals (Sweden)

    SHESHIDHAR REDDY ADDULA

    2017-09-01

    Full Text Available In this paper, a novel soft-switched interleaved DC-DC converter which provides a high voltage gain of 12 is proposed. Voltage gain of the basic interleaved boost converter is extended by using diode-capacitor multiplier (DCM cells. The switches are operated at a nominal duty ratio of 0.5. The voltage stress on the power switches and diodes is only a fraction of the output voltage. To enhance the operating power conversion efficiency, the switches are turned ON at zero voltage condition. Experimental results of 18-216V, 100W prototype converter validate the operating principle and the advantageous features of the presented converter.

  17. Power flow analysis for DC voltage droop controlled DC microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Chaudhary, Sanjay; Dragicevic, Tomislav

    2014-01-01

    This paper proposes a new algorithm for power flow analysis in droop controlled DC microgrids. By considering the droop control in the power flow analysis for the DC microgrid, when compared with traditional methods, more accurate analysis results can be obtained. The algorithm verification...... is carried out by comparing the calculation results with detailed time domain simulation results. With the droop parameters as variables in the power flow analysis, their effects on power sharing and secondary voltage regulation can now be analytically studied, and specialized optimization in the upper level...... control can also be made accordingly. Case studies on power sharing and secondary voltage regulation are carried out using proposed power flow analysis....

  18. Pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2008-01-01

    This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,

  19. Light-weight DC to very high voltage DC converter

    Science.gov (United States)

    Druce, R.L.; Kirbie, H.C.; Newton, M.A.

    1998-06-30

    A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

  20. Evaluation of Volatilization Potential for Legacy Chlordane in Military Housing Area Soils

    Science.gov (United States)

    2011-10-01

    Headquarters, U.S. Army Corps of Engineers Washington, DC 20314-1000 ERDC/EL TR-11-15 ii Abstract: The U.S. Air Force used the chlorinated pesticide...While this phenomenon may not be very significant when dealing with volatile compounds such as chlorinated solvents, it may have very significant...document. Washington, D.C.: Office of Water. Vinopal, J.H., and K.L. Olds. 1977. Investigation of suspected nonoccupational human intoxication

  1. Washington: What's Ahead

    Science.gov (United States)

    Shiffrin, Mark A.

    1978-01-01

    By summer of 1978, the Office of Civil Rights expects higher education institutions to be in compliance with Title IX of the Higher Education Act, the provision mandating equal treatment of the sexes. Implications are discussed, especially in the areas of access for the handicapped and the tuition tax credit. (LBH)

  2. Lupine consumption by cattle in the scablands of Eastern Washington.

    Science.gov (United States)

    The Scabland region of eastern Washington is dominated by annual grasses and in some areas by Lupinus leucophyllus (velvet lupine). The purpose of these trials was to document the consumption of velvet lupine and relate the amount of lupine eaten by pregnant cows with the incidence of crooked calv...

  3. 1954 forest fire weather in western Oregon and Washington.

    Science.gov (United States)

    Owen P. Cramer

    1954-01-01

    For the second successive fire season forest fire weather in western Oregon and Washington was far below normal severity. The low danger is reflected in record low numbers of fires reported by forestry offices of both States and by the U. S. Forest Service for their respective protection areas. Although spring and fall fire weather was near normal, a rain-producing...

  4. Damage to western Washington forests from November 1955 cold wave.

    Science.gov (United States)

    John W. Duffield

    1956-01-01

    The cold wave that occurred throughout the Pacific Northwest in mid-November 1955 caused serious damage to the forests of western Washington. Observations indicate that heavy mortality can be expected in 30- to 40-year-old stands in some areas. In addition, widespread damage was suffered by natural regeneration and young plantations, and by 1-0 stock in some forest...

  5. Solar DC Microgrid for Rural Electrification-A Case Study

    Directory of Open Access Journals (Sweden)

    Debojyoti Sen

    2016-03-01

    Full Text Available Currently around 1.5 billion people worldwide live without access to electricity, and without a concerted effort, this number is not likely to drop. Grid extension is often very costly and not feasible in isolated areas. In such situations, electricity mini-grids can power household use and local businesses. The expansion of rural electrification is occurring mainly under the RGGVY (Rajiv Gandhi Grameen Vidhyutikaran Yojona scheme in India. As among all the renewable sources solar is the most explored one, DC micro grid has become one of the most popular and proposed option for rural electrification. Various policies and delivery models are being implemented on DC micro grid. But Is Dc Micro grid really a viable option for rural electrification? This paper focuses on the various socio-economic and even the technical aspect of DC micro Grid to check its viability and the study is aided by survey reports on the same on various rural villages of India. The paper also tried to integrate the schemes that is introduced for rural electrification with DC micro grid and try to analyze whether DC micro Grid is a sustainable option of rural electrification.

  6. Linking DC together with TRSL

    DEFF Research Database (Denmark)

    Haxthausen, Anne; Yong, Xia

    1999-01-01

    for high-level specifications of real-time requirementsand TRSL for specifying real-time implementations in the form of timed communicating concurrent processes.In order to link DC and TRSL together in a well-founded way, we formally define what it means for a TRSL process to satisfy a DC requirement...... of constraints on the durations of states of the system, i.e. at a high level of abstraction.However, as a state-based logic, it lacks the ability to specifysequential programs and communicating concurrent processes at a concrete level. The Timed RAISE Specification Language (TRSL) [XG99] has this ability.......TRSL is a real-time extension of the RAISE Specification Language (RSL) [Rlg92] which together with its associated method [Rmg95]and tools has shown to be very useful in the industrial development of software systems. Therefore, a promising approach for the development of real-time systemscould be to use DC...

  7. Urban Growth Areas, Urban Growth Areas: as part of the Comprehensive Plan - Land Use plan. The most common use is for a determination during the review process for a feasibility of development projects. The areas are used to plan infrastructure improvements and funding alloc, Published in 2003, 1:7200 (1in=600ft) scale, Washington County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Urban Growth Areas dataset current as of 2003. Urban Growth Areas: as part of the Comprehensive Plan - Land Use plan. The most common use is for a determination...

  8. Libraries in Washington: MedlinePlus

    Science.gov (United States)

    ... this page: https://medlineplus.gov/libraries/washington.html Libraries in Washington To use the sharing features on ... enable JavaScript. Bellingham PeaceHealth St. Joseph Medical Center Library 2901 Squalicum Parkway Bellingham, WA 98225 360-788- ...

  9. Foundations of DC plasma sources

    Science.gov (United States)

    Tomas Gudmundsson, Jon; Hecimovic, Ante

    2017-12-01

    A typical dc discharge is configured with the negative cathode at one end and a positive anode at the other end, separated by a gas filled gap, placed inside a long glass cylinder. A few hundred volts between the cathode and anode is required to maintain the discharge. The type of discharge that is formed between the two electrodes depends upon the pressure of the working gas, the nature of the working gas, the applied voltage and the geometry of the discharge. We discuss the current–voltage characteristics of the discharge as well as the distinct structure that develops in the glow discharge region. The dc glow discharge appears in the discharge current range from μA to mA at 0.5–300 Pa pressure. We discuss the various phenomena observed in the dc glow discharge, including the cathode region, the positive column, and striations. The dc glow discharge is maintained by the emission of secondary electrons from the cathode target due to the bombardment of ions. For decades, the dc glow discharge has been used as a sputter source. Then it is often operated as an obstructed abnormal glow discharge and the required applied voltage is in the range 2–5 kV. Typically, the cathode target (the material to be deposited) is connected to a negative voltage supply (dc or rf) and the substrate holder faces the target. The relatively high operating pressure, in the range from 2 to 4 Pa, high applied voltages, and the necessity to have a conductive target limit the application of dc glow discharge as a sputter source. In order to lower the discharge voltage and expand the operation pressure range, the lifetime of the electrons in target vicinity is increased through applying magnetic field, by adding permanent magnets behind the cathode target. This arrangement is coined the magnetron sputtering discharge. The various configurations of the magnetron sputtering discharge and its applications are described. Furthermore, the use of dc discharges for chemical analysis, the

  10. Modeling and analysis of fractional order DC-DC converter.

    Science.gov (United States)

    Radwan, Ahmed G; Emira, Ahmed A; AbdelAty, Amr M; Azar, Ahmed Taher

    2017-07-11

    Due to the non-idealities of commercial inductors, the demand for a better model that accurately describe their dynamic response is elevated. So, the fractional order models of Buck, Boost and Buck-Boost DC-DC converters are presented in this paper. The detailed analysis is made for the two most common modes of converter operation: Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM). Closed form time domain expressions are derived for inductor currents, voltage gain, average current, conduction time and power efficiency where the effect of the fractional order inductor is found to be strongly present. For example, the peak inductor current at steady state increases with decreasing the inductor order. Advanced Design Systems (ADS) circuit simulations are used to verify the derived formulas, where the fractional order inductor is simulated using Valsa Constant Phase Element (CPE) approximation and Generalized Impedance Converter (GIC). Different simulation results are introduced with good matching to the theoretical formulas for the three DC-DC converter topologies under different fractional orders. A comprehensive comparison with the recently published literature is presented to show the advantages and disadvantages of each approach. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  11. An Integrated Multifunctional Bidirectional AC/DC and DC/DC Converter for Electric Vehicles Applications

    Directory of Open Access Journals (Sweden)

    Liwen Pan

    2016-06-01

    Full Text Available This paper presents an on-board vehicular battery charger that integrates bidirectional AC/DC converter and DC/DC converter to achieve high power density for application in electric vehicles (EVs. The integrated charger is able to transfer electrical energy between the battery pack and the electric traction system and to function as an AC/DC battery charger. The integrated charger topology is presented and the design of passive components is discussed. The control schemes are developed for motor drive system and battery-charging system with a power pulsation reduction circuit. Simulation results in MATLAB/Simulink and experiments on a 30-kW motor drive and 3.3-kW AC/DC charging prototype validate the performance of the proposed technology. In addition, power losses, efficiency comparison and thermal stress for the integrated charger are illustrated. The results of the analyses show the validity of the advanced integrated charger for electric vehicles.

  12. Residential Energy Efficiency Potential: Washington

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-27

    Energy used by Washington single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  13. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    Science.gov (United States)

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  14. 33 CFR 165.1310 - Strait of Juan de Fuca and adjacent coastal waters of Northwest Washington; Makah Whale Hunting...

    Science.gov (United States)

    2010-07-01

    ... adjacent coastal waters of Northwest Washington; Makah Whale Hunting-Regulated Navigation Area. 165.1310... and adjacent coastal waters of Northwest Washington; Makah Whale Hunting—Regulated Navigation Area. (a.... Datum: NAD 1983. (b) During a whale hunt, while the international numeral pennant five (5) is flown by a...

  15. Managing wastewater in coastal urban areas

    National Research Council Canada - National Science Library

    Committee on Wastewater Management for Coastal Urban Areas

    1993-01-01

    ... and Technology Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1993 Copyrightthe cannot be not from book, paper however, version for formatting, original authoritative the typesetting-specific the as from created publication files XML from other this and of recompose...

  16. DC Microgrids—Part II

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Lu, Xiaonan; Quintero, Juan Carlos Vasquez

    2016-01-01

    . Closely coupled with protection, conflicting grounding objectives, e.g. minimization of stray current and common mode voltage are explained and several practical solutions are presented. Also, standardization efforts for DC systems are addressed. Finally, concluding remarks and important future research...

  17. Electricity-AC versus DC

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Electricity - AC versus DC. D P Sen Gupta. General Article Volume 2 Issue 10 October 1997 pp 46-53. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/10/0046-0053. Author Affiliations.

  18. Voltage Weak DC Distribution Grids

    NARCIS (Netherlands)

    Hailu, T.G.; Mackay, L.J.; Ramirez Elizondo, L.M.; Ferreira, J.A.

    2017-01-01

    This paper describes the behavior of voltage weak DC distribution systems. These systems have relatively small system capacitance. The size of system capacitance, which stores energy, has a considerable effect on the value of fault currents, control complexity, and system reliability. A number of

  19. Geophysical logs of selected wells in Eastern Washington

    Energy Technology Data Exchange (ETDEWEB)

    Stoffel, K.L.; Widness, S.

    1983-12-01

    This report consists of geophysical well logs compiled during studies of the geohydrology and low temperature geothermal resources of eastern Washington. The geophysical logs are divided into two groups. Part A consists of wells concentrated in the Moses Lake-Ritzville-Connell area. Results of the geohydrologic study are discussed in Widness (1983, 1984). Part B consists of wells outside of the Moses Lake-Ritzville-Connell study area.

  20. Water resources of King County, Washington

    Science.gov (United States)

    Richardson, Donald; Bingham, J.W.; Madison, R.J.; Williams, R.

    1968-01-01

    Although the total supply of water in King County is large, water problems are inevitable because of the large and rapidly expanding population. The county contains a third of the 3 million people in Washington, most of the population being concentrated in the Seattle metropolitan area. King County includes parts of two major physiographic features: the western area is part of the Puget Sound Lowland, and the eastern area is part of the Cascade Range. In these two areas, the terrain, weather, and natural resources (including water) contrast markedly. Average annual precipitation in the county is about 80 inches, ranging from about 30 inches near Puget Sound to more than 150 inches in parts of the Cascades. Annual evapotranspiration is estimated to range from 15 to 24 inches. Average annual runoff ranges from about 15 inches in the lowlands to more than 100 inches in the mountains. Most of the streamflow is in the major basins of the county--the Green-Duwamish, Lake Washington, and Snoqualmie basins. The largest of these is the Snoqualmie River basin (693 square miles), where average annual runoff during the period 1931-60 was about 79 inches. During the same period, annual runoff in the Lake Washington basin ( 607 square miles) averaged about 32 inches, and in the Green-Duwamish River basin (483 square miles), about 46 inches. Seasonal runoff is generally characterized by several high-flow periods in the winter, medium flows in the spring, and sustained low flows in the summer and fall. When floods occur in the county they come almost exclusively between October and March. The threat of flood damage is greatest on the flood plaits of the larger rivers, but in the Green-Duwamish Valley the threat was greatly reduced with the completion of Howard A. Hanson Dam in 1962. In the Snoqualmie River basin, where no such dam exists, the potential damage from a major flood increases each year as additional land is developed in the Snoqualmie Valley. 0nly moderate amounts of

  1. SoC-Based Droop Method for Distributed Energy Storage in DC Microgrid Applications

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Sun, Kai; Guerrero, Josep M.

    2012-01-01

    With the progress of distributed generation nowadays, microgrid is employed to integrate different renewable energy sources into a certain area. For several kinds of renewable sources have DC outputs, DC microgrid has drawn more attention recently. Meanwhile, to deal with the uncertainty in the o...

  2. Sheppard-Taylor Isolated High Boost DC-DC Converter

    DEFF Research Database (Denmark)

    Chub, Andrii; Siwakoti, Yam Prasad; Vinnikov, Dmitri

    2017-01-01

    be implemented with fewer passive components. Soft-switching in semiconductors allows achieving high efficiency. In addition, the input side current is continuous. The operating principle and the design guidelines derived for the converter are presented. Theoretical results are supported with experimental......This paper presents a new galvanically isolated step-up dc-dc converter intended for low-power but high step-up applications. The proposed converter is capable of regulating output voltage within a wide range of the input voltage or load variations. In contrast to competitors, the converter can...... results obtained using a 100 W prototype. The converter proposed can be used in photovoltaic module level power electronics applications, where a wide input voltage and load regulation range are highly demanded....

  3. A Current-Fed Isolated Bidirectional DC-DC Converter

    DEFF Research Database (Denmark)

    Sun, Xiaofeng; Wu, Xiaoying; Shen, Yanfeng

    2017-01-01

    This paper proposes a current-fed isolated bidirectional DC-DC converter (CF-IBDC) which has the advantages of wide input voltage range, low input current ripple, low conduction losses, and soft switching over the full operating range. Compared with conventional CF-IBDCs, the voltage spikes...... of the low-voltage (LV) side switches in the proposed converter can be eliminated without additional clamp circuits. The converter adopts the pulse width modulation (PWM) plus hybrid phase-shift control scheme such that the bus voltage can match the output voltage by means of the transformer. Thus......, the current stresses and conduction losses of the converter become lower. In addition, the practical ZVS of the secondary-side switches can be realized by adjusting the phase-shift angle within the secondary side when in light load or no load condition. The operating principles and characteristics including...

  4. Dilation and Curettage (D&C)

    Science.gov (United States)

    ... For Patients About ACOG Dilation and Curettage (D&C) Home For Patients Search FAQs Dilation and Curettage ( ... February 2016 PDF Format Dilation and Curettage (D&C) Special Procedures What is dilation and curettage (D& ...

  5. NAMMA DC-8 DROPSONDE V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NAMMA DC-8 Dropsonde dataset were collected by the DC-8 dropsonde system, which uses an integrated, highly accurate, GPS-located atmospheric profiling dropsonde...

  6. Tsunami Preparedness in Washington (video)

    Science.gov (United States)

    Loeffler, Kurt; Gesell, Justine

    2010-01-01

    Tsunamis are a constant threat to the coasts of our world. Although tsunamis are infrequent along the West coast of the United States, it is possible and necessary to prepare for potential tsunami hazards to minimize loss of life and property. Community awareness programs are important, as they strive to create an informed society by providing education and training. This video about tsunami preparedness in Washington distinguishes between a local tsunami and a distant event and focus on the specific needs of this region. It offers guidelines for correct tsunami response and community preparedness from local emergency managers, first-responders, and leading experts on tsunami hazards and warnings, who have been working on ways of making the tsunami affected regions safer for the people and communities on a long-term basis. This video was produced by the US Geological Survey (USGS) in cooperation with Washington Emergency Management Division (EMD) and with funding by the National Tsunami Hazard Mitigation Program.

  7. Implementation of hierarchical control in DC microgrids

    DEFF Research Database (Denmark)

    Jin, Chi; Wang, Peng; Xiao, Jianfang

    2014-01-01

    DC microgrids are becoming popular in low-voltage distribution systems due to the better compatibility with photovoltaic panels, electric vehicles, and dc loads. This paper presents a practical dc microgrid developed in the Water and Energy Research Laboratory (WERL) in the Nanyang University of ...

  8. Toward the Universal DC Distribution System

    NARCIS (Netherlands)

    Mackay, L.J.; van der Blij, N.H.; Ramirez Elizondo, L.M.; Bauer, P.

    2017-01-01

    AbstractDue to an increasing number of power generation units and load devices operating with direct current (DC) at distribution level, there is a potential benefit of leading efforts toward building a DC distribution system. However, the implementation of DC distribution systems faces important

  9. Hierarchical Power Sharing Control in DC Microgrids

    DEFF Research Database (Denmark)

    Peyghami, Saeed; Mokhtari, Hossein; Blaabjerg, Frede

    2016-01-01

    Because of the advances in power electronics, DC-based power systems, have been used in industrial applications such as data centers [18], space applications [10], aircraft [12], offshore wind farms, electric vehicles [56], DC home systems [5, 20], and high-voltage DC transmission systems...

  10. Determination of Presence and Habitat Suitability for the Indiana Bat (Myotis sodalis) and Gray Bat (Myotis grisescens) for the Pine Ford Study Area, Jefferson, Washington, St. Louis and Franklin Counties, Missouri,

    Science.gov (United States)

    1982-01-01

    of poison ivy (Rhus radicans) and stinging nettle ( Urtica dioica ). All permanently flowing tributaries within the study area, as well as several...located that were narrow in width and shallow in depth. 4 J,0 When possible, areas of the stream were also chosen where trees created a tunnel-like effect ...to approximate 100 percent cover between riparian canopies in order to create a tunnel-like effect so that virtually all bats passing through the fly

  11. Development of innovative superconducting DC power cable

    Energy Technology Data Exchange (ETDEWEB)

    Matsushita, Teruo; Kiuchi, Masaru [Dept. of Computer Science and Electronics Kyushu Institute of Technology, Iizuka (Japan)

    2017-09-15

    It is required to reduce the cost of superconducting cable to realize a superconducting DC power network that covers a wide area in order to utilize renewable energy. In this paper a new concept of innovative cable is introduced that can enhance the current-carrying capacity even though the same superconducting tape is used. Such a cable can be realized by designing an optimal winding structure in such a way that the angle between the tape and magnetic field becomes small. This idea was confirmed by preliminary experiments for a single layer model cable made of Bi-2223 tapes and REBCO coated conductors. Experiments of three and four layer cables of practical sizes were also done and it was found that the current-carrying capacity increased as theoretically predicted. If the critical current properties of commercial superconducting tapes are further improved in a parallel magnetic field, the enhancement will become pronounced and this technology will surely contribute to realization of superconducting DC power network.

  12. High efficiency high step-up DC/DC converters - a review

    National Research Council Canada - National Science Library

    Tomaszuk, A; Krupa, A

    2011-01-01

    .... This review is focused on high efficiency step-up DC/DC converters with high voltage gain. The differentiation is based on the presence or lack of galvanic isolation. A comparison and discussion of different DC/DC step-up topologies will be performed across number of parameters and presented in this paper.

  13. High Power Zero-Voltage and Zero-Current Switching DC-DC Converters

    Directory of Open Access Journals (Sweden)

    Jaroslav Dudrik

    2005-01-01

    Full Text Available The paper presents principles and properties of the soft switching PWM DC-DC converters. The attention is focused mainly on high power applications and thus the full-bridge inverters are used in DC-DC converters. Considerations are also given to the control methods and principles of the switching and conduction losses reduction.

  14. A Family of Four Quadrant DC/DC Converters with Reduced Number of Components

    DEFF Research Database (Denmark)

    Mostaan, Ali; Soltani, Mohsen

    2015-01-01

    A family of four quadrant DC/DC converters is presented in this paper. Compare with existing four quadrant DC/DC converters that have been introduced in literature, the proposed converters have lower number of components. There are two bidirectional switches, two coupled inductors and one capacitor...

  15. 75 FR 36579 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-30, DC-10-30F, DC-10-30F (KC...

    Science.gov (United States)

    2010-06-28

    ... Corporation Model DC- 10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, and MD-10-30F...). SUMMARY: We propose to adopt a new airworthiness directive (AD) for certain Model DC-10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC- 10-40, DC10-40F, and MD-10-30F airplanes. This proposed AD would...

  16. 75 FR 61352 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-10-30, DC-10-30F, DC-10-30F (KC...

    Science.gov (United States)

    2010-10-05

    ... Corporation Model DC- 10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC-10-40F, and MD-10-30F... new airworthiness directive (AD) for certain Model DC-10-30, DC-10-30F, DC-10-30F (KC-10A and KDC-10), DC-10-40, DC- 10-40F, and MD-10-30F airplanes. This AD requires doing a one-time inspection of the...

  17. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Yan, Wenli

    2016-01-01

    changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.......It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC) is proposed...... for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load...

  18. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    Directory of Open Access Journals (Sweden)

    Haojie Wang

    2016-07-01

    Full Text Available It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC is proposed for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.

  19. FLYWHEEL AND A DC MACHINE

    Directory of Open Access Journals (Sweden)

    IVAN ALCALÁ

    2014-01-01

    Full Text Available Este artículo describe el análisis, modelado y simulación de un vehículo eléctrico (EV enfocado al desarrollo de un banco de pruebas para reproducir la dinámica del EV. El banco está formado por un drive de motor de inducción (IM acoplado directamente a una máquina de DC y a un volante de inercia a través de una transmisión. El volante de inercia y la máquina de DC reproducen la dinámica y las fuerzas que actúan en el vehículo. Se propone una metodología para diseñar un banco de pruebas de EV para estudiar el comportamiento de vehículos eléctricos cercano a las condiciones de operación reales. El análisis de las fuerzas en el EV en conjunto con la máquina DC define las condiciones de operación del EV. El modelado y la simulación son desarrollados en MATLAB/Simulink, el banco de pruebas implementado es controlado por un DSP. Finalmente, los resultados de simulación y experimentales obtenidos validan el funcionamiento del banco de prueba.

  20. Active DC Bus Signaling Control Method for Coordinating Multiple Energy Storage Devices in DC Microgrid

    OpenAIRE

    Li, Fulong; Lin, Zhengyu; Qian, Zhongnan; Wu, Jiande

    2017-01-01

    This paper will be presented in 2017 Second IEEE International Conference on DC Microgrids (ICDCM) on 28th June 2017. Abstract: Management of multiple energy storage devices in a DC microgrid is a challenge. Conventional method, such as droop control, cannot ensure accurate current sharing in coordinating multiple battery banks, which limits the DC microgrid system performance. This paper proposed an active DC bus signaling (ADBS) method to coordinate multiple battery banks in a DC microg...

  1. Cultural Resources Review for Closure of the nonradioactive Dangerous Waste Landfill and Solid Waste Landfill in the 600 Area, Hanford Site, Benton County, Washington, HCRC# 2010-600-018R

    Energy Technology Data Exchange (ETDEWEB)

    Gutzeit, Jennifer L.; Kennedy, Ellen P.; Bjornstad, Bruce N.; Sackschewsky, Michael R.; Sharpe, James J.; DeMaris, Ranae; Venno, M.; Christensen, James R.

    2011-02-02

    The U.S. Department of Energy Richland Operations Office is proposing to close the Nonradioactive Dangerous Waste Landfill (NRDWL) and Solid Waste Landfill (SWL) located in the 600 Area of the Hanford Site. The closure of the NRDWL/SWL entails the construction of an evapotranspiration cover over the landfill. This cover would consist of a 3-foot (1-meter) engineered layer of fine-grained soil, modified with 15 percent by weight pea gravel to form an erosion-resistant topsoil that will sustain native vegetation. The area targeted for silt-loam borrow soil sits in Area C, located in the northern central portion of the Fitzner/Eberhardt Arid Lands Ecology (ALE) Reserve Unit. The pea gravel used for the mixture will be obtained from both off-site commercial sources and an active gravel pit (Pit #6) located just west of the 300 Area of the Hanford Site. Materials for the cover will be transported along Army Loop Road, which runs from Beloit Avenue (near the Rattlesnake Barricade) east-northeast to the NRDWL/SWL, ending at State Route 4. Upgrades to Army Loop Road are necessary to facilitate safe bidirectional hauling traffic. This report documents a cultural resources review of the proposed activity, conducted according to Section 106 of the National Historic Preservation Act of 1966.

  2. Annual Research Progress Report (U.S. Army Institute of Dental Research, Washington, DC)

    Science.gov (United States)

    1978-10-01

    Materials) Natural History of Oral Lesions Encountered in the Soldier (Pathology) Role of Pressurized Water Lavage in the Practice of Military Dentistry...17 18 19 20 21 -TT: ’^~~~’~~~~*~~l~~~~m***~m*r~mmmmmmm 1 ’ Page No. % \\ DA ÜH 6038 Development of Endodontic Procedures for... medicament -carrying wound coverings, fixation devices in maxillofacial wounds and slow-drug-release systems are continuing to show positive results. The

  3. Proceedings of the Acquisition Research Symposium Held in Washington, DC, October 1989

    Science.gov (United States)

    1989-10-01

    different states of nature. In this paper we provide a general formulation of this type of decision milking . The Dempster-Shafer evidential...Dmmmtat 1 1 t 4 t A-RFl C RFO D RFP. E 6uati«Di F. RavoDan G. Pre*«* H Clvifutin KQ I RmoDM «« CUriutioDi J. AnnndonutoRFF K. Rc« uHt lor BAJO

  4. IEEE 1990 International Symposium on Electromagnetic Compatibility, Washington, DC, Aug. 21-23, 1990, Record

    Science.gov (United States)

    The present conference discusses topics in EM shielding effectiveness, system-level EMC, EMP effects, circuit-level EMI testing, EMI control, analysis techniques for system-level EMC, EMP protective measures, EMI test methods, electrostatic-discharge testing, printed circuit-board design for EMC, and EM environment effects. Also discussed are EMI measurement procedures, EM spectrum-management issues for the 21st century, antenna and propagation effects on EMI testing, EMI control in cables, socioeconomic aspects of EMC, systemwide EMI controls, and EM radiation and coupling.

  5. Between the holocaust museum in Washington D.C and Ghana's ...

    African Journals Online (AJOL)

    Crossroads of People, Crossroads of Trade” at the Cape Coast Castle Museum. While the exhibition represents five hundred years of Ghana‟s history, it stands as an epochal reflection of the economic and socio-political events marking the ...

  6. The Role of Federal Troops in Quelling Civil Disturbance in Washington, DC, April 1968

    Science.gov (United States)

    1993-01-01

    than 700 fires illuminated the night sky. Rampaging blacks there forced Army units in combat gear to set up machine-gun emplacements outside the Capitol...shooting looters and to cease shooting out streetlights , which they had been doing because of their fear of snipers.ŕ 0 "Major General Charles P

  7. MTADS Geophysical Survey of Potential Burial Pits Along the C&O Canal in Washington, DC

    National Research Council Canada - National Science Library

    Nelson, Herbert

    2002-01-01

    .... We have identified, however, 30 magnetic anomalies in and adjacent to the survey site. Many of the anomalies have been identified with ferrous metal objects visible on the surface or arise from shallow trash and scrap. There are eight anomalies that appear to arise from relatively large ferrous metal objects buried at depths greater than 6 to 8 feet. These remalning anomalies may require further investigation.

  8. Proceedings of the ICA Conference (4th, Washington, D.C., November 11-13, 1970).

    Science.gov (United States)

    ICA Information, 1971

    1971-01-01

    The proceedings of the Fourth Conference of the Intergovernmental Council for ADP-ICA, are contained in this, the 7th issue of the ICA-Information, the Council's official publication. The proceedings include the edited minutes of the sessions, which covered the following topics: Management information systems for the government, Policy…

  9. Imported Malaria over Fifteen Years in an Inner City Teaching Hospital of Washington DC.

    Science.gov (United States)

    Yeruva, Sri Lakshmi Hyndavi; Sinha, Archana; Sarraf-Yazdy, Mariam; Gajjala, Jhansi

    2016-06-01

    As endemic malaria is not commonly seen in the United States, most of the cases diagnosed and reported are associated with travel to and from the endemic places of malaria. As the number of imported cases of malaria has been increasing since 1973, it is important to look into these cases to study the morbidity and mortality associated with this disease in the United States. In this study, we would like to share our experience in diagnosing and treating these patients at our institution. We did a retrospective chart review of 37 cases with a documented history of imported malaria from 1998 to 2012. Among them, 16 patients had complicated malaria during that study period, with a mean length of hospital stay of 3.5 days. Most common place of travel was Africa, and chemoprophylaxis was taken by only 11% of patients. Travel history plays a critical role in suspecting the diagnosis and in initiating prompt treatment.

  10. Computers in Libraries, 2000: Proceedings (15th, Washington, D.C., March 15-17, 2000).

    Science.gov (United States)

    Nixon, Carol, Comp.; Burmood, Jennifer, Comp.

    Topics of the Proceedings of the 15th Annual Computers in Libraries Conference (March 15-17, 2000) include: Linux and open source software in an academic library; a Master Trainer Program; what educators need to know about multimedia and copyright; how super searchers find business information online; managing print costs; new technologies in wide…

  11. Computers in Libraries Annual Conference (17th, Washington, DC, March 13-15, 2002): Collected Presentations.

    Science.gov (United States)

    Nixon, Carol, Comp.

    This book contains presentations from the 17th annual Computers in Libraries Conference. Topics covered include: chatting with a librarian; verbots for library Web sites; collaborative IT (Information Technology) planning at Montgomery County Public Library (Maryland); designing a local government taxonomy; Weblogs; new roles for librarians in…

  12. Andrews AFB, Washington DC Revised Uniform Summary of Surface Weather Observations (RUSSWO) Parts A-F.

    Science.gov (United States)

    1981-10-15

    13.8 12.7 NNW .3 1o2 4.1 2.5 .6 .2 ___ __ __ 8.9 10.2 VARK ____ CAL.M95 TOTAL NUMIER OP OSUVATIONS90 USAFETAC -i-0-8.5 (OL-Al PUIvIOUS ICITIONS OF... VARK I (CALM 1 TOTAL NUMala OF OBERVATIONS 900 UISAFETAC "ORm 0.8.5 (OL.A) PREVIOUS EDITI0NS OF TIS FORNI ARE OBSOLETECJA 64 GLOBAL...wsw .9. 1.3 . 1 . w 2.4 1. .81 4*4 4a wNw .6’ 9_ . 6 T.t __ ___ ___- 2oSr 5.6 __ S_ .96 2_2_ If_ _ _ _ __ _ _ _ 35 VARK - i i 19.5 35.1 -0. -. .2...1

  13. Toxicity of Anacostia River, Washington, DC, USA, sediment fed to mute swans (Cygnus olor)

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, W.N.; Day, D.; Melancon, M.J.; Sileo, L.

    2000-03-01

    Sediment ingestion is sometimes the principal route by which waterfowl are exposed to environmental contaminants, and at severely contaminated sites waterfowl have been killed by ingesting sediment. Mute swans (Cygnus olor) were fed a diet for 6 weeks with a high but environmentally realistic concentration (24%) of sediment from the moderately polluted Anacostia River in the District of Columbia, USA, to estimate the sediment's toxicity. Control swans were fed the same diet without the sediment. Five organochlorine compounds were detected in the treated diets, but none of 22 organochlorine compounds included in the analyses was detected in livers of the treated swans. The concentrations of 24 polynuclear aromatic hydrocarbons measured in the treated diet were as high as 0.80 mg/kg, and they were thought to have been responsible for the observed induction of hepatic microsomal monooxygenase activity in livers. A concentration of 85 mg/kg of lead in the diet was enough to decrease red blood cell ALAD activity but was not high enough to cause more serious effects of lead poisoning. The dietary concentrations of Al, Fe, V, and Ba were high compared to the concentrations of these elements known to be toxic in laboratory feeding studies. However, the lack of accumulation in the livers of the treated swans suggested that these elements were not readily available from the ingested sediment. The authors did not study all potential toxic effects, but, on the basis of those that they did consider, they concluded that the treated swans were basically healthy after a chronic exposure to the sediment.

  14. Proceedings of the Seminar on Freelance Indexing (2nd, Washington, D.C., January 13, 1979).

    Science.gov (United States)

    Tebo, Jay D., Ed.

    Transcribed and edited from tape recordings and prepared papers, these proceedings present the topics covered in the four sessions of the Second Seminar on Freelance Indexing: (1) how to get started as an indexer--making contracts, setting up the office, billing and bookkeeping, reference tools, filing for trade-name, and indexing apprenticeship;…

  15. GPS/GNSS Antenna Characterization : GPS-ABC Workshop V RTCA Washington, DC October 14, 2016.

    Science.gov (United States)

    2016-10-14

    One component of the Department of Transportations GPS Adjacent Band : Compatibility Study is the characterization of GPS/GNSS receiver antennas : Such characterization is needed to: : Compare radiated and conducted (wired) test result...

  16. Bike Ed '77: A Conference Report (Washington, D.C., May 4-6, 1977).

    Science.gov (United States)

    Johnson (Lawrence) and Associates, Inc., Washington, DC.

    As a result of intensified need for sound safety education programs for both young and mature bicyclists due to the dramatic increase in bicycling as a form of transportation and recreation, the first national conference on bicyclist safety education was held--Bike Ed '77. Major purposes of the conference were to stimulate communication among…

  17. Invited Speaker Support for SBP Conference Series (SBP 2014) held in April, 2014 in Washington, DC.

    Science.gov (United States)

    2014-07-23

    Robin Baker and Paul Burns Break 9:30 AM Refreshments: muffins, bagels, hardcooked eggs, fruit, beverages Keynote 10:00 AM Keynote by...Emoticon Use in First and Second Languages Cecilia Aragon, Nan-Chen Chen, Judith Kroll and Laurie Feldman SBP Poster Social Maintenance and

  18. 77 FR 37737 - Environmental Impact Statement for the Northeast Corridor Between Washington, DC, New York, NY...

    Science.gov (United States)

    2012-06-22

    ... development of the program. NEC FUTURE is being advanced consistent with the federal High-Speed Intercity... socioeconomic conditions, ecological resources, water resources, cultural resources, hazardous contamination... June 18, 2012. John Tunna, Director of the Office of Research and Development, Federal Railroad...

  19. Proceedings of Conference on Variable-Resolution Modeling, Washington, DC, 5-6 May 1992

    Science.gov (United States)

    1992-05-01

    Other models convert the wire frame diagram into a faceted image and degrade that image as a function of sensor and atmospheric characteristics. There...data supporting an iid intermessage time model is readily accessible, no organization currently collects information on the intergeneration time of

  20. Cost-effectiveness of trees for demand-side management Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-01

    Trees can reduce demand for air conditioning to cool buildings by shading residences and lowering summertime air temperatures. During winter, trees can reduce heating needs by lowering wind speeds and thereby reducing infiltration of cold air. On the otherhand, winter shade from improperly located trees can increase heating requirements. Projections from computer simulations indicate that 100 million mature trees in U.S. cities (3 trees for every other single family home) could reduce energy use for heating and cooling by 30 billion kWh and reduce carbon dioxide emissions by as much as 9 million tons per year. This energy analysis is part of a larger study that quantifies costs and benefits of proposed tree plantings in 12 U.S. cities. While energy savings is an important benefit from community forests, other benefits (e.g., air quality improvement, reduced stormwater runoff, increased property values) can have equal or greater value. Tree planting, care, and other costs (e.g., water-sewer line repair, green waste disposal, litigation/liability, program administration) from the cost-benefit study can be used to help estimate costs associated with a tree planting program for demand-side management. Data from this energy analysis should be of direct value to local utilities, urban foresters, planners, landscape designers, and non-profit tree planting groups.

  1. McMillan Pumping Station, Washington, D.C.; Hydraulic Model Investigation.

    Science.gov (United States)

    1980-09-01

    about visual observations of flow conditions with each of the pump operating combinations. Various stages of air - entrained vortices and other smaller...vortices were observed during these tests. An air - entrained surface vortex can clearly be seen in Photo 4 where dye was inserted to contrast its outline...causes of the adverse hydraulic conditions were the uneven 16 "I L EVELA. SURFACE VORTEX B. -WALL VORTEX FLOO VOREX c SECTION A-A VORTEX FORMATIONS A

  2. Proceedings: energy from urban wastes workshop, Washington, DC, September 11-12, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, A.S.; Brooks, C. (eds.)

    1979-06-01

    This workshop, for members of public interest groups, was sponsored by DOE's Urban Waste Technology Branch to provide information on the use of urban waste as an energy resource. A separate abstract was prepared for each of seven presentations plus the Summary of discussions. Two acts are included as appendices: (1) Public Law 95-238: Department of Energy Act of 1978 - Civilian Applications; and (2) Public Law 94-580: Resource Conservation and Recovery Act of 1976.

  3. Learning from Recent Advances in Measuring Teacher Effectiveness. Meeting Summary (Washington, DC, August 9, 2012)

    Science.gov (United States)

    Institute of Education Sciences, 2012

    2012-01-01

    On August 9, 2012, the Institute of Education Sciences (IES) convened a meeting of researchers and U.S. Department of Education (ED) and IES staff to discuss recent advances in measuring teacher effectiveness. The objectives of the meeting were to: (1) Identify and discuss recent advances in the use of value-added models (VAMs) and student growth…

  4. Learning from Recent Advances in Measuring Teacher Effectiveness (Washington, DC, August 9, 2012)

    Science.gov (United States)

    Betebenner, Damian; Braun, Henry; Corcoran, Sean; Darling-Hammond, Linda; Friedman, John; Goldhaber, Daniel; Ho, Andrew; Kane, Thomas; Ladd, Helen; Pianta, Robert; Rockoff, Jonah; Rothstein, Jesse

    2012-01-01

    On August 9, 2012, the Institute of Education Sciences (IES) convened a meeting of researchers and U.S. Department of Education (ED) and IES staff to discuss recent advances in measuring teacher effectiveness. The objectives of the meeting were to: (1) Identify and discuss recent advances in the use of value-added models (VAMs) and student growth…

  5. Proceedings of Nutrition Education Conference, February 20-22, 1967, Washington, D.C.

    Science.gov (United States)

    Agricultural Research Service (USDA), Washington, DC.

    Included are reports of present nutritional habits and problems in different communities, a discussion of psychological factors influencing consumer decisions about foods, and suggestions for the use of media such as magazines, newspapers, radio, and television to communicate basic nutritional concepts. Several new programs are reported concerned…

  6. Symposium on International Terrorism Held in Washington, DC on 2-3 December 1985

    Science.gov (United States)

    1985-12-01

    nonpolitical realms such as sexual practices. The Weathermen, for example, attempted to ban monogamy. Menmbers of terrorist organizations are often...the literature to the "Identification with the aggressor" (A. Freud ), as manifesting itself in the positive attitude some hostages show towards their...captors. This has als been referred to as "Stockholm syndrome", a term coined when a female Swedish hostage fell in love with her captor. Perhaps one

  7. Criminal Justice Statistics for Washington, D.C. and Other Major Cities

    National Research Council Canada - National Science Library

    2001-01-01

    On July 20, 2001, we testified at an oversight hearing-which focused on prisoner releases and reintegration programs-held by the Subcommittee on the District of Columbia, House Committee on Government Reform...

  8. A History of the Chemistry Division, Naval Research Laboratory, Washington, D.C., 1927-1982.

    Science.gov (United States)

    1983-04-22

    20. Cheryl Joyal 21. Chuck Dulcey 21. Rich Colton 21. Leslie Polka 22. Bob Fox 22. Greg Burks 22. Pete Mah 23. Bob Brady 23. Jim Holtzclaw 24. Elaine...Delozier 21. Douglas Nordman 22. Mark Ross 22. Robert Nowak 23. Marc Beebe 23. Terrence Barrett 24. Steve Lloyd 24. Mark Beymer 4 25. Graham Cheek 26

  9. Pluralism, Place, and Gertrude Bonnin's Counternativism from Utah to Washington, DC

    Science.gov (United States)

    Newmark, Julianne

    2012-01-01

    In the first three decades of the twentieth century, racial nativism wielded considerable direct and indirect influence on policies that affected broader American attitudes concerning Native American people. In this three-decade period, many factors caused the kinds of national insecurity and instability that make a cultural climate ripe for…

  10. Breakfast and Learning in Children. Symposium Proceedings (Washington, DC, April 22, 1999).

    Science.gov (United States)

    Food, Nutrition, and Consumer Services (USDA), Washington, DC. Center for Nutrition Policy and Promotion.

    Noting that many schools do not participate in the U.S. Department of Agriculture's School Breakfast Program despite evidence that poor nutrition affects children's school attendance and performance, this document presents the proceedings of a 1999 symposium on links between breakfast and school performance and the implications for public policy.…

  11. Walter Reed Army Medical Center, Washington, DC Annual Progress Report FY-89. Volume 2. Part 1

    Science.gov (United States)

    1990-01-02

    predictor of future complications such asmyocardial infarction, development of unstable angina or sudden death. I TECHNICAL APPROACH One to six months...after hospitalization for acute ., unstable angina or congestive heart failure with ischemic etiology, sf-idy subjects will have a physical exam...Continuous Long-term Cultures 3 KEYWORDS: stem cells, differentiation PRINCIPAL INVESTIGATOR: La Russa, Vincent PhD ASSOCIATES: Salvado, August COL MC; Knight

  12. 77 FR 74347 - Prevailing Rate Systems; Abolishment of the Washington, DC, Special Wage Schedule for Printing...

    Science.gov (United States)

    2012-12-14

    ... Printing Positions AGENCY: U.S. Office of Personnel Management. ACTION: Final rule. SUMMARY: The U.S... (FWS) special wage schedule for printing and lithographic positions. Printing and lithographic... fund FWS wage schedule. This change is necessary because Federal employment in printing and...

  13. NOAA & Academia Partnership Building Conference. Highlights (3rd, Washington, DC, November 14-15, 2001).

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Silver Spring, MD.

    In November 2001 the National Oceanic and Atmospheric Administration (NOAA) hosted the third NOAA and Academia Partnership to evaluate, maintain, and expand on efforts to optimize NOAA-university cooperation. Close partnership between the NOAA and U.S. universities has produced many benefits for the U.S. economy and the environment. Based on the…

  14. Image Understanding Proceedings of a Workshop Held at Washington, DC, April 23, 1981

    Science.gov (United States)

    1981-04-01

    discussion of MIT work on Image Sketch, the line terminations ,orresponding to the rulings Understanding, see Volume 2 of Artificial Intelligece : an...York 14627 Abstract Image Understanditog (I.U.) shares with It is a tenet of’ this research that a Artificial Intelligence the need for program to do...field of Artificial specific value or range of a feature. The Intelligence (A.I.). The use of knowledge Operator an1 Image Problem Expert can to control

  15. 77 FR 58439 - Environmental Impact Statement for the Northeast Corridor Between Washington, DC, New York, NY...

    Science.gov (United States)

    2012-09-20

    ... trip characteristics. It will also ask for travel preferences under alternative choice scenarios that... travel preference questions. The Phase 2 Survey is estimated to take 15 minutes to complete. The... Household Travel Attitudes and Behavior. Type of Request: New information collection requirement. Status...

  16. 78 FR 63250 - Workshop; November 18-19, 2013 in Washington, DC

    Science.gov (United States)

    2013-10-23

    ... nuclear utilities for onsite storage will affect future handling, storage, transportation and geologic... Rowe at [email protected] or Karyn Severson at [email protected] . For information on meeting logistics...

  17. 75 FR 39969 - National Mall and Memorial Parks, Washington, DC; Final Environmental Impact Statement and...

    Science.gov (United States)

    2010-07-13

    ... unchanged. Existing spaces which have not been designed for the current level of use would continue to... maintenance and aging infrastructure, pedestrian and bicycle circulation issues, and the lack of adequate... National Mall, with its memorials and planned vistas, would be protected, and the designed landscape would...

  18. Minutes of the Speech Understanding Workshop Convened on 13 November 1975 in Washington, D.C.

    Science.gov (United States)

    1975-11-13

    function in order for bipolar signals to be recordable as an intensity transmittance on a medium such as photographic film. So Fj(x) is written as F(x...8217 plete mirror sweep as plane is N-I N- IIN-I QM~clc 2c3 f~trnhmn (13) UxY =- - fnam k n0( m= k-0 (12) yPd Elxamk -0 Om A’- reet tr-apt ZI L 2 ’ 2 -- b

  19. Acceleration and Performance Modeling Workshop, Washington, DC, 14-17 May 79,

    Science.gov (United States)

    1979-12-01

    LATERAL TRACKING ERROR AND MODEL ESTIMATES . . . . . . . . . 17 8 EXTENSIONS OF THIS WORK TO STUDY PHYSIOLOGY. . . .. .. . 18 9 SENSITIVITY USED TO...INFORMATION ON PHYSIOLOGY? o WHAT OCM PARAMETER IS IMPORTANT IN THE MODELING OF THE STRESS DATA? o EXTENSION OF THE MODEL (OCM) TO BETTER UNDERSTAND THE...vascular compliance is totally linear and independent of transmural pressure which we know not to be the case. In fact, what we know to be the case from

  20. 76 FR 55157 - Final Public Meeting in Washington, DC for the Proposed Keystone XL Project

    Science.gov (United States)

    2011-09-06

    ... Presidential Permit to the applicant would serve the national interest. This decision on the application will... name or number is called or they will forfeit their time. Comments: Remarks made at the meetings will... consideration of the proposed Keystone XL pipeline. Each speaker will be allowed 3-5 minutes to make remarks...

  1. Toxicity of Anacostia River, Washington, DC, USA, sediment fed to mute swans (Cygnus olor)

    Science.gov (United States)

    Beyer, W.N.; Day, D.; Melancon, M.J.; Sileo, L.

    2000-01-01

    Sediment ingestion is sometimes the principal route by which waterfowl are exposed to environmental contaminants, and at severely contaminated sites waterfowl have been killed by ingesting sediment. Mute swans (Cygnus olor) were fed a diet for six weeks with a high but environmentally realistic concentration (24%) of sediment from the moderately polluted Anacostia River in the District of Columbia, to estimate the sediment?s toxicity. Control swans were fed the same diet without the sediment. Five organochlorine compounds were detected in the treated diets but none of 22 organochlorine compounds included in the analyses were detected in livers of the treated swans. The concentrations of 24 polynuclear aromatic hydrocarbons measured in the treated diet were as high as 0.80 mg/kg and they were thought to have been responsible for the observed induction of hepatic microsomal monooxygenase activity in livers. A concentration of 85 mg/kg of lead in the diet was enough to decrease red blood cell ALAD activity but was not high enough to cause more serious effects of lead poisoning. The dietary concentrations of Al, Fe, V, and Ba were high compared to the concentrations of these elements known to be toxic in laboratory feeding studies, but these elements did not accumulate in the livers of the treated swans and probably were not readily available in the sediment. Although ingestion of the Anacostia River sediment caused subtle toxicological effects in swans, we concluded from pathological examinations and weight data that the treated swans remained basically healthy.

  2. 78 FR 4790 - Security Zone, Potomac and Anacostia Rivers; Washington, DC

    Science.gov (United States)

    2013-01-23

    ... to address the aforementioned security concerns and to take steps to prevent the catastrophic impact... bypassing the security measures established on shore for the events and engaging in waterborne terrorist.... Although the security zone will apply to the entire width of the Potomac and Anacostia Rivers, traffic may...

  3. "Records of Rights": A New Exhibit at the National Archives in Washington, D.C.

    Science.gov (United States)

    Hussey, Michael

    2014-01-01

    America's founding documents--the Declaration of Independence, the Constitution, and the Bill of Rights--are icons of human liberty. But the ideals enshrined in those documents did not initially apply to all Americans. They were, in the words of Martin Luther King, Jr., "a promissory note to which every American was to fall heir."…

  4. The association between fracture rates and neighborhood characteristics in Washington, DC children

    Science.gov (United States)

    Ryan, Leticia Manning; Guagliardo, Mark; Teach, Stephen J.; Wang, Jichuan; Marsh, Jennifer E.; Singer, Steven A.; Wright, Joseph L.; Chamberlain, James M.

    2013-01-01

    Effects of neighborhood contextual features have been found for many diseases, including bone fractures in adults. Our study objective was to evaluate the association between neighborhood characteristics and pediatric bone fracture rates. We hypothesized that neighborhood indices of deprivation would be associated with higher fracture rates. Pediatric bone fracture cases treated at a tertiary, academic, urban pediatric emergency department between 2003 – 2006 were mapped to census block groups using geographical information systems software. Fracture rates were calculated as fractures per 1,000 children in each census block. Exploratory factor analysis of socioeconomic indicators was performed using 2000 census block data. Factor scores were used to predict odds of bone fracture at the individual level while adjusting for mean age, gender composition, and race/ethnicity composition at census block level using our sample data. We analyzed 3764 fracture visits in 3557 patients representing 349 distinct census blocks groups. Fracture rates among census blocks ranged from 0 to 207 per 1,000 children/study period. Logistic regression modeling identified two factors (race/education and large families) associated with increased fracture risk. Census variables reflecting African American race, laborer/service industry employment, long term block group residence and lower education levels strongly loaded on the race/education factor. The large families factor indicated the children-to-families ratio within the block group. The poverty factor was not independently associated with fracture risk. Thus, neighborhood characteristics are associated with risk for fractures in children. These results can help inform translational efforts to develop targeted strategies for bone fracture prevention in children. PMID:23360838

  5. Southeast Asia: Problems and Prospects Held at Washington, DC on 4-5 December 1984.

    Science.gov (United States)

    1985-06-01

    divisions. By the 1972 Easter offensive, about 90 percent of the day-to-day combat in the South was by PAVN, that is, North Vietnamese regulars in uniform...were cakravatans, universalistic rulers who unified and conquered to bring about the new Buddhist era. It is not surprising that folk mythology

  6. World Materials Summit (3rd). Held in Washington, DC on 9-12 October, 2011

    Science.gov (United States)

    2012-05-23

    will supply 45.8 million CFL bulbs to replace incandescent bulbs on a free and voluntary basis. They also have an appliance replacement program that...ySKSiBois.Slanfo-d Urive’silyGicaalC » male & Energy Project End Of OH 2006 (a^er Join Edvua’da American Aascciatort Df Pel’oietri Geoogisia). SRI...accelerate developments in this field WHY & WHERE are there international cooperation needs - Tools - Scale - Critical players - Benefits to these

  7. Biennial Wind Energy Conference and Workshop, 5th, Washington, DC, October 5-7, 1981, Proceedings

    Science.gov (United States)

    1982-05-01

    The results of studies funded by the Federal government to advance the state of the art of wind energy conversion systems (WECS) construction, operation, applications, and financial viability are presented. The economics of WECS were considered in terms of applicable tax laws, computer simulations of net value of WECS to utilities, and the installation of Mod-2 2.5 MW and WTS-4 4MW wind turbines near Medicine Bow, WY to test the operation of two different large WECS on the same utility grid. Potential problems of increasing penetration of WECS-produced electricity on a utility grid were explored and remedies suggested. The structural dynamics of wind turbines were analyzed, along with means to predict potential noise pollution from large WECS, and to make blade fatigue life assessments. Finally, Darrieus rotor aerodynamics were investigated, as were dynamic stall in small WECS and lightning protection for wind turbines and components.

  8. 78 FR 1753 - Security Zone, Potomac and Anacostia Rivers; Washington, DC

    Science.gov (United States)

    2013-01-09

    ..., including the waters of the Georgetown Channel Tidal Basin; and all waters of the Anacostia River, from..., Federalism, if it has a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of...

  9. A Feedback Passivation Design for DC Microgrid and Its DC/DC Converters

    Directory of Open Access Journals (Sweden)

    Feifan Ji

    2016-12-01

    Full Text Available There are difficulties in analyzing the stability of microgrids since they are located on various network structures. However, considering that the network often consists of passive elements, the passivity theory is applied in this paper to solve the above-mentioned problem. It has been formerly shown that when the network is weakly strictly positive real (WSPR, the DC microgrid is stable if all interfaces between the microgrid and converters are made to be passive, which is called interface passivity. Then, the feedback passivation method is proposed for the controller design of various DC–DC converters to achieve the interface passivity. The interface passivity is different from the passivity of closed-loop systems on which the passivity based control (PBC concentrates. The feedback passivation design is detailed for typical buck converters and boost converters in terms of conditions that the controller parameters should satisfy. The theoretical results are verified by a hardware-in-loop real-time labotray (RTLab simulation of a DC microgrid with four generators.

  10. Next-Generation Shipboard DC Power System

    DEFF Research Database (Denmark)

    Jin, Zheming; Sulligoi, Giorgio; Cuzner, Rob

    2016-01-01

    . At present, the research of dc microgrid has investigated and developed a series of advanced methods in control, management and objective-oriented optimization, which would found the technical interface enabling the future applications in multiple industrial areas, such as smart buildings, electric vehicles......In recent years, more and more evidence suggests that the global energy system is on the verge of a drastic revolution. The evolutionary development in power electronic technologies, the emerging high-performance energy storage devices, as well as the ever increasing penetration of renewable energy...... in research interests and industrial applications. In addition, the concept of flexible and smart distribution has also been proposed, which tends to exploit distributed generation and pack the distributed RESs and local electrical loads as an independent and self-sustainable entity, namely microgrid...

  11. Washington: a guide to geothermal energy development

    Energy Technology Data Exchange (ETDEWEB)

    Bloomquist, R.G.; Basescu, N.; Higbee, C.; Justus, D.; Simpson, S.

    1980-06-01

    Washington's geothermal potential is discussed. The following topics are covered: exploration, drilling, utilization, legal and institutional setting, and economic factors of direct use projects. (MHR)

  12. DC Voltage Droop Control Implementation in the AC/DC Power Flow Algorithm: Combinational Approach

    DEFF Research Database (Denmark)

    Akhter, F.; Macpherson, D.E.; Harrison, G.P.

    2015-01-01

    In this paper, a combinational AC/DC power flow approach is proposed for the solution of the combined AC/DC network. The unified power flow approach is extended to include DC voltage droop control. In the VSC based MTDC grids, DC droop control is regarded as more advantageous in terms...... of operational flexibility, as more than one VSC station controls the DC link voltage of the MTDC system. This model enables the study of the effects of DC droop control on the power flows of the combined AC/DC system for steady state studies after VSC station outages or transient conditions without needing...... to use its complete dynamic model. Further, the proposed approach can be extended to include multiple AC and DC grids for combined AC/DC power flow analysis. The algorithm is implemented by modifying the MATPOWER based MATACDC program and the results shows that the algorithm works efficiently....

  13. Using PBL to Improve Educational Outcomes and Student Satisfaction in the Teaching of DC/DC and DC/AC Converters

    Science.gov (United States)

    Martinez-Rodrigo, Fernando; Herrero-De Lucas, Luis Carlos; de Pablo, Santiago; Rey-Boue, Alexis B.

    2017-01-01

    This paper examines the question of how to use project-based learning to increase student performance and satisfaction in a power electronics course addressing the topics of dc/dc and dc/ac converters, the assembly of a dc/dc converter, and the use of a commercial speed drive. A detailed presentation of the methodology is shown, and the results…

  14. Elimination of output voltage oscillations in DC-DC converter using PWM with PI controller

    Directory of Open Access Journals (Sweden)

    Sreenivasappa Veeranna Bhupasandra

    2010-01-01

    Full Text Available In this paper the SIMULINK model of a PWM controlled DC-DC converter is modeled using switching function concept to control the speed of the DC motor. The presence of the voltage oscillation cycles due to higher switching frequency in the DC-DC converter is identified. The effect of these oscillations on the output voltage of the converter, Armature current, Developed torque and Speed of the DC motor is analyzed. In order to minimize the oscillation cycles the PI controller is proposed in the PWM controller.

  15. Block clustering based on difference of convex functions (DC) programming and DC algorithms.

    Science.gov (United States)

    Le, Hoai Minh; Le Thi, Hoai An; Dinh, Tao Pham; Huynh, Van Ngai

    2013-10-01

    We investigate difference of convex functions (DC) programming and the DC algorithm (DCA) to solve the block clustering problem in the continuous framework, which traditionally requires solving a hard combinatorial optimization problem. DC reformulation techniques and exact penalty in DC programming are developed to build an appropriate equivalent DC program of the block clustering problem. They lead to an elegant and explicit DCA scheme for the resulting DC program. Computational experiments show the robustness and efficiency of the proposed algorithm and its superiority over standard algorithms such as two-mode K-means, two-mode fuzzy clustering, and block classification EM.

  16. Chaos analysis and chaotic EMI suppression of DC-DC converters

    CERN Document Server

    Zhang, Bo

    2014-01-01

    Introduces chaos theory, its analytical methods and the means to apply chaos to the switching power supply design DC-DC converters are typical switching systems which have plenty of nonlinear behaviors, such as bifurcation and chaos. The nonlinear behaviors of DC-DC converters have been studied heavily over the past 20 years, yet researchers are still unsure of the practical application of bifurcations and chaos in switching converters. The electromagnetic interference (EMI), which resulted from the high rates of changes of voltage and current, has become a major design criterion in DC-DC co

  17. 75 FR 434 - Notice of Intent to Repatriate Cultural Items: Thomas Burke Memorial Washington State Museum...

    Science.gov (United States)

    2010-01-05

    ... the southern end. This area falls within the Southern Lushootseed language group of Salish cultures... Lake Washington south of the mouth of the Sammamish River. This area falls within the Southern Lushootseed language group of Salish cultures. The Sammamish people primarily occupied this area (Ruby and...

  18. Elevation of HLA-G-expressing DC-10 cells in patients with gastric cancer.

    Science.gov (United States)

    Xu, Dan-Ping; Shi, Wei-Wu; Zhang, Tong-Tong; Lv, Hai-Yan; Li, Jing-Bo; Lin, Aifen; Yan, Wei-Hua

    2016-09-01

    DC-10 is a distinct subset of human tolerogenic dendritic cells (DCs) which express high levels of human leukocyte antigen-G (HLA-G). DC-10 could induce adaptive type 1 regulatory T cells through the IL-10 dependent ILT4/HLA-G signaling pathway. However, the significance of DC-10 in malignancies remains unclear. In this study, the frequency and mean fluorescence intensity (MFI) of HLA-G+ DC-10 in the peripheral blood of 124 patients with gastric cancer (GC) and 130 normal controls was analyzed with flow cytometry. Plasma sHLA-G was analyzed with ELISA. Results showed both the percentages of peripheral HLA-G+ DC-10 (median: 0.13% vs 0.01%; pDC-10 in GC patients was strongly relative to the tumor grade (p=0.021). sHLA-G levels in GC patients were significantly higher than in healthy controls (median: 85.80U/ml vs 61.20U/ml; pDC-10 and plasma sHLA-G (p>0.05). However, the increased HLA-G+ DC-10, HLA-G MFI and plasma sHLA-G in patients with gastric cancer could be a diagnostic factor with the area under the ROC curve with 0.947 (pDC-10 could play, the increased DC-10 might play an important role in immune suppression for patients with gastric cancer, while more studies are necessary to illustrate the clinical relevance of DC-10 in cancer patients. Copyright © 2016 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  19. Corrections Education. Washington's Community and Technical Colleges

    Science.gov (United States)

    Washington State Board for Community and Technical Colleges, 2015

    2015-01-01

    The Washington State Department of Corrections contracts with community colleges to provide basic education and job training at each of the state's 12 adult prisons so upon release, individuals are more likely to get jobs and less likely to return. Washington State community colleges build a bridge for offenders to successfully re-enter…

  20. Aerospace Training. Washington's Community and Technical Colleges

    Science.gov (United States)

    Washington State Board for Community and Technical Colleges, 2014

    2014-01-01

    Aerospace is an economic powerhouse that generates jobs and fuels our economy. Washington's community and technical colleges produce the world-class employees needed to keep it that way. With about 1,250 aerospace-related firms employing more than 94,000 workers, Washington has the largest concentration of aerospace expertise in the nation. To…

  1. Financial Reporting at the Washington Headquarters Services

    Science.gov (United States)

    2001-03-15

    FINANCIAL REPORTING AT THE WASHINGTON HEADQUARTERS SERVICES Report No. D-2001-081 March 15, 2001...to) ("DD MON YYYY") Title and Subtitle Financial Reporting at the Washington Headquarters Services Contract or Grant Number Program Element Number...underlying financial reporting processes that cause abnormal balances on the trial balances of Other Defense Organizations. An account balance is abnormal

  2. High gain high efficiency resonant DC-DC converter

    Science.gov (United States)

    Shang, Fei

    Low voltage power sources have played an important role in applications such as automotive system, renewable energy power generation and so on, where require a high gain DC-DC step-up converter. The converter is going to sustain a very high input current which can bring many design challenges in the existing topologies, such as high component current stress and power loss, complex and costly design for magnetic components, high input current ripple, etc. A new topology of high gain DCDC step-up converter proposed in this dissertation. The topology has many merits such as high gain capability, high efficiency, low components stress and requirement of the transformer, simple topology with less number of active switching devices, and easy to control. The dissertation carries out theoretical analysis of the proposed topology under different operating modes and the voltage gain has been deduced for each mode. The design of circuit components has been well studied, including the power devices current stress and power, the selection of transformer turns-ratio, the design method of the resonant tank and input current ripple. System dynamic state-space models are acquired by using generalized averaging method. Small signal model of the converter is achieved by linearization of the dynamic model around the operating points. The stability study indicates that the open loop system is stable at all operating points, except some operating points containing RHP zeros which can cause closed loop system unstable. The parameter sensitivity study shows that the system transfer function is not greatly affected by the variation of the leakage inductance and load resistance. A design of PI controller is implemented to achieve the output voltage regulation. Simulations have been carried out to validate the circuit operation and support the design analysis. A 2kW prototype has been built for experimental testing. The experimental results are in a good agreement with the theoretical

  3. Two new families of high-gain dc-dc power electronic converters for dc-microgrids

    Science.gov (United States)

    Prabhala, Venkata Anand Kishore

    Distributing the electric power in dc form is an appealing solution in many applications such as telecommunications, data centers, commercial buildings, and microgrids. A high gain dc-dc power electronic converter can be used to individually link low-voltage elements such as solar panels, fuel cells, and batteries to the dc voltage bus which is usually 400 volts. This way, it is not required to put such elements in a series string to build up their voltages. Consequently, each element can function at it optimal operating point regardless of the other elements in the system. In this dissertation, first a comparative study of dc microgrid architectures and their advantages over their ac counterparts is presented. Voltage level selection of dc distribution systems is discussed from the cost, reliability, efficiency, and safety standpoints. Next, a new family of non-isolated high-voltage-gain dc-dc power electronic converters with unidirectional power flow is introduced. This family of converters benefits from a low voltage stress across its switches. The proposed topologies are versatile as they can be utilized as single-input or double-input power converters. In either case, they draw continuous currents from their sources. Lastly, a bidirectional high-voltage-gain dc-dc power electronic converter is proposed. This converter is comprised of a bidirectional boost converter which feeds a switched-capacitor architecture. The switched-capacitor stage suggested here has several advantages over the existing approaches. For example, it benefits from a higher voltage gain while it uses less number of capacitors. The proposed converters are highly efficient and modular. The operating modes, dc voltage gain, and design procedure for each converter are discussed in details. Hardware prototypes have been developed in the lab. The results obtained from the hardware agree with those of the simulation models.

  4. Simultaneous distribution of AC and DC power

    Science.gov (United States)

    Polese, Luigi Gentile

    2015-09-15

    A system and method for the transport and distribution of both AC (alternating current) power and DC (direct current) power over wiring infrastructure normally used for distributing AC power only, for example, residential and/or commercial buildings' electrical wires is disclosed and taught. The system and method permits the combining of AC and DC power sources and the simultaneous distribution of the resulting power over the same wiring. At the utilization site a complementary device permits the separation of the DC power from the AC power and their reconstruction, for use in conventional AC-only and DC-only devices.

  5. Washington International Renewable Energy Conference 2008 Pledges: Methodology and Assumptions Summary

    Energy Technology Data Exchange (ETDEWEB)

    Babiuch, B.; Bilello, D. E.; Cowlin, S. C.; Mann, M.; Wise, A.

    2008-08-01

    The 2008 Washington International Renewable Energy Conference (WIREC) was held in Washington, D.C., from March 4-6, 2008, and involved nearly 9,000 people from 125 countries. The event brought together worldwide leaders in renewable energy (RE) from governments, international organizations, nongovernmental organizations, and the private sector to discuss the role that renewables can play in alleviating poverty, growing economies, and passing on a healthy planet to future generations. The conference concluded with more than 140 governments, international organizations, and private-sector representatives pledging to advance the uptake of renewable energy. The U.S. government authorized the National Renewable Energy Laboratory (NREL) to estimate the carbon dioxide (CO2) savings that would result from the pledges made at the 2008 conference. This report describes the methodology and assumptions used by NREL in quantifying the potential CO2 reductions derived from those pledges.

  6. A Survey on Voltage Boosting Techniques for Step-Up DC-DC Converters

    DEFF Research Database (Denmark)

    Forouzesh, Mojtaba; Siwakoti, Yam Prasad; Gorji, Saman Asghari

    2016-01-01

    Step-up dc-dc converters are used to boost the voltage level of the input to a higher output level. Despite of its features such as simplicity of implementation, the fundamental boost dc-dc converter has shortcomings such as low boost ability and low power density. With these limitations, researc......Step-up dc-dc converters are used to boost the voltage level of the input to a higher output level. Despite of its features such as simplicity of implementation, the fundamental boost dc-dc converter has shortcomings such as low boost ability and low power density. With these limitations......, researches on new voltage boosting techniques are inevitable for various power converter applications. This can be achieved either by additional magnetic or by electric field storage elements with switching elements (switch and/or diode) in different configurations. Such combination of primary voltage...

  7. Digitally intensive DC-DC converter for extreme space environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Space Micro –Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator...

  8. Ultra-high Efficiency DC-DC Converter using GaN Devices

    DEFF Research Database (Denmark)

    Ramachandran, Rakesh

    2016-01-01

    with the PCB layout and the magnetics. This thesis mainly covers the design and implementation of various high efficiency isolated dcdc converters in the range of 1 to 2.5 kW of output power. Both hard-switched and soft-switched topologies in isolated dc-dc converters has been studied and realized......The demands for high efficiency dc-dc power converters are increasing day by day in various applications such as telecommunication, data-centers, electric vehicles and various renewable energy systems. Silicon (Si) has been used as the semiconductor material in majority of the power devices...... properties of GaN devices can be utilized in power converters to make them more compact and highly efficient. This thesis entitled “Ultra-high Efficiency DC-DC Converter using GaN devices” focuses on achieving ultra-high conversion efficiency in an isolated dc-dc converter by the optimal utilization of Ga...

  9. Digitally intensive DC-DC converter for extreme space environments Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Space Micro-Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator core...

  10. Real-Time Implementation of a Fuzzy Logic Controller for DC-DC Switching Converters

    National Research Council Canada - National Science Library

    Rubaai, Ahmed

    2005-01-01

    This report presents a successful implementation of a fuzzy logic controller structure for dc-dc switching converters and evaluates experimentally its sensitivity for variable supply voltages and load...

  11. Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low...

  12. Development of a DC-DC conversion powering scheme for the CMS Phase-1 pixel upgrade

    CERN Document Server

    Feld, Lutz Werner; Karpinski, Waclaw; Klein, Katja; Lipinski, Martin; Preuten, Marius; Max Rauch; Rittich, David Michael; Sammet, Jan Domenik; Wlochal, Michael

    2014-01-01

    A novel powering scheme based on the DC-DC conversion technique will be exploited to power the CMS Phase-1 pixel detector. DC-DC buck converters for the CMS pixel project have been developed, based on the AMIS5 ASIC designed by CERN. The powering system of the Phase-1 pixel detector is described and the performance of the converter prototypes is detailed, including power efficiency, stability of the output voltage, shielding, and thermal management. Results from a test of the magnetic field tolerance of the DC-DC converters are reported. System tests with pixel modules using many components of the future pixel barrel system are summarized. Finally first impressions from a pre-series of 200 DC-DC converters are presented.

  13. Decentralized Nonlinear Controller Based SiC Parallel DC-DC Converter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is aimed at demonstrating the feasibility of a Decentralized Control based SiC Parallel DC-DC Converter Unit (DDCU) with targeted application for...

  14. Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex NASA space power electronic systems can be configured using a small number of qualified hybrid DC-DC converter and...

  15. DIAGNOSTIC/PROGNOSTIC EXPERIMENTS FOR CAPACITOR DEGRADATION AND HEALTH MONITORING IN DC-DC CONVERTERS

    Data.gov (United States)

    National Aeronautics and Space Administration — Studying and analyzing the ageing mechanisms of electronic components avionics in systems such as the GPS and INAV are of critical importance. In DC-DC power...

  16. Improved Control Strategy for T-type Isolated DC/DC Converters

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Wang, Yanbo

    2017-01-01

    . Under the proposed strategy, the primary circulating current flows through the auxiliary switches (metal–oxide–semiconductor field-effect transistors) instead of their body diodes in free-wheeling periods. Such feature can reduce conduction losses, thereby improving the efficiency of T-type isolated DC......T-type isolated DC/DC converters have recently attracted attention due to their numerous advantages, including few components, low cost, and symmetrical operation of transformers. This study proposes an improved control strategy for increasing the efficiency of T-type isolated DC/DC converters....../DC converters. The operation principles and performances of T-type isolated DC/DC converters under the proposed control strategy are analyzed in detail and verified through the simulation and experimental results....

  17. Washington State biomass data book

    Energy Technology Data Exchange (ETDEWEB)

    Deshaye, J.A.; Kerstetter, J.D.

    1991-07-01

    This is the first edition of the Washington State Biomass Databook. It assess sources and approximate costs of biomass fuels, presents a view of current users, identifies potential users in the public and private sectors, and lists prices of competing energy resources. The summary describes key from data from the categories listed above. Part 1, Biomass Supply, presents data increasing levels of detail on agricultural residues, biogas, municipal solid waste, and wood waste. Part 2, Current Industrial and Commercial Use, demonstrates how biomass is successfully being used in existing facilities as an alternative fuel source. Part 3, Potential Demand, describes potential energy-intensive public and private sector facilities. Part 4, Prices of Competing Energy Resources, shows current suppliers of electricity and natural gas and compares utility company rates. 49 refs., 43 figs., 72 tabs.

  18. HTS DC Transmission Line for Megalopolis Grid Development

    Science.gov (United States)

    Kopylov, S.; Sytnikov, V.; Bemert, S.; Ivanov, Yu; Krivetskiy, I.; Romashov, M.; Shakaryan, Yu; Keilin, V.; Shikov, A.; Patrikeev, V.; Lobyntsev, V.; Shcherbakov, V.

    2014-05-01

    Using of HTS AC and DC cables in electric power grids allows increasing of the transferred power, losses diminishing, decreasing of exclusion zone areas, the enhancement of the environmental conditions and fire/explosion safety of electric power systems. However, the use of DC superconducting cable lines together with converters brings additional advantages as reduction of losses in cables and suitable lowering of refrigerating plant capacity, as well as the realization of the function of short-circuit currents limitation by means of the appropriate setting of converter equipment. Russian Federal Grid Company and its R&D Center started the construction of the DC HTS power transmission line which includes the cable itself, cryogenic equipment, AC/DC converters, terminals and cable coupling boxes. This line will connect two substations in Saint-Petersburg - 330 kV "Centralnaya" and 220 kV "RP-9". The length of this HTS transmission line will be about 2500 meters. Nowadays are developed all the elements of the line and technologies of the cable manufacturing. Two HTS cable samples, each 30 m length, have been made. This paper describes the results of cables tests.

  19. Prevalence of antibodies to Toxoplasma gondii in raccoons (Procyon lotor) from an urban area of Northern Virginia.

    Science.gov (United States)

    Hancock, Katie; Thiele, Lori A; Zajac, Anne M; Elvingert, Francois; Lindsay, David S

    2005-06-01

    Raccoons (Procyon lotor) are intermediate hosts for Toxoplasma gondii, and clinical toxoplasmosis in raccoons has been reported. A 2-yr serological survey was conducted to determine the prevalence of antibodies to T. gondii in raccoons collected from Fairfax County, Virginia, a suburban/urban area outside Washington, D.C. Serum samples from 256 raccoons were examined for T. gondii antibodies at a 1:50 dilution using the modified direct agglutination test. Results indicated that 216 (84.4%) of the raccoons had been exposed to T. gondii. Our results indicate that raccoons in this area of Virginia are frequently exposed to T. gondii. Domestic cats were common in the study area and may have served as a source of oocysts for raccoons and the food items of raccoons.

  20. Effects of resistive bodies on DC electrical soundings

    Directory of Open Access Journals (Sweden)

    L. Alfano

    1996-06-01

    Full Text Available Some deep DC electrical soundings, performed in alpine and apenninic areas with the continuous polar dipole-dipole spread, show apparent resistivity curves with positive slopes. Measured values of apparent resistivity reach 30000 Wm. Applying the "surface charges" method we developed three dimensional mathematical models, by means of which we can state simple rules for determining the minimum extensions of the deep resistive bodies, fundamental information for a more precise interpretation of the field results.

  1. A Decentralized Current-Sharing Controller Endows Fast Transient Response to Parallel DC-DC Converters

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Han, Renke

    2017-01-01

    This paper proposes a decentralized current-sharing control strategy to endow fast transient response to paralleled DC-DC converters systems, such as DC microgrids or distributed power systems. The proposed controller consist of two main control loops: an external voltage droop control for curren...

  2. Fuzzy Logic Controlled DC-DC Converter Based Dynamic Voltage Restorer

    Directory of Open Access Journals (Sweden)

    Mustafa İnci

    2015-12-01

    Full Text Available This paper presents fuzzy logic controlled dc-dc boost converter based Dynamic Voltage Restorer (DVR to compensate severe voltage sag problems in an electrical system. DVR absorbs real power from battery to compensate voltage sags in the system. This condition causes reduction in voltage magnitude of dc-link capacitor. Additionally, DVR requires large dc capacitors to compensate long and severe voltage sags in the system. In this study, dc-dc boost converter is connected to DVR for keeping dc link voltage constant. For this propose, a control algorithm based on Fuzzy Logic (FL control is developed for dc-dc boost converter. The main contribution of this study is that Fuzzy Logic (FL is firstly used to generate reference signal for PWM signals of dc-dc converter applied in DVR. FL is a very flexible controller which keeps the dc link voltage constant during voltage sag. The performance results of proposed study are verified with PSCAD/EMDTC.

  3. Effect of DC/mDC iontophoresis and terpenes on transdermal permeation of methotrexate: in vitro study.

    Science.gov (United States)

    Prasad, R; Koul, V; Anand, S; Khar, R K

    2007-03-21

    The systemic toxicity caused by methotrexate limits its use and transdermal delivery would be a possible alternative. Transdermal permeation of methotrexate loaded into polyacrylamide-based hydrogel patch, across mice skin was studied in vitro after pretreatment with terpenes and ethanol, alone or in combination with iontophoresis (DC/mDC). Polyacrylamide patches gave the maximum flux as compared to the copolymers of acrylamide and acrylic acid. Of the terpenes used, pure menthol showed maximum enhancement (38%), whereas pure limonene elicited a minimum of 9.9% enhancement. Binary combination of menthol and ethanol increased the permeation to 54.9%, which was further enhanced to 93.69% and 117% when used in combination with DC and square wave (mDC) iontophoresis, respectively. ATR-FTIR of the stratum corneum treated with terpenes showed a split in the asymmetric C-H stretching vibrations along with decrease in peak heights and areas of asymmetric, symmetric C-H stretching, C=O stretching and amide bands. A split in amide II band was observed with iontophoresis. ATR-FTIR studies suggest conformational changes in the lipid-protein domains thereby increasing permeation. Histopathological studies on treated skin samples, gave an insight about the anatomical changes brought by the application of various enhancers. Binary mixture of menthol and ethanol in combination with square wave gave best results.

  4. A digitally controlled PWM/PSM dual-mode DC/DC converter

    Science.gov (United States)

    Shaowei, Zhen; Bo, Zhang; Ping, Luo; Sijian, Hou; Jingxin, Ye; Xiao, Ma

    2011-11-01

    A digitally controlled pulse width modulation/pulse skip modulation (PWM/PSM) dual-mode buck DC/DC converter is proposed. Its operation mode can be automatically chosen as continuous conduction mode (CCM) or discontinuous conduction mode (DCM). The converter works in PSM at DCM and in 2 MHz PWM at CCM. Switching loss is reduced at a light load by skipping cycles. Thus high conversion efficiency is realized in a wide load current. The implementations of PWM control blocks, such as the ADC, the digital pulse width modulator (DPWM) and the loop compensator, and PSM control blocks are described in detail. The parameters of the loop compensator can be programmed for different external component values and switching frequencies, which is much more flexible than its analog rivals. The chip is manufactured in 0.13 μm CMOS technology and the chip area is 1.21 mm2. Experimental results show that the conversion efficiency is high, being 90% at 200 mA and 67% at 20 mA. Meanwhile, the measured load step response shows that the proposed dual-mode converter has good stability.

  5. Electronic DC transformer with high power density

    NARCIS (Netherlands)

    Pavlovský, M.

    2006-01-01

    This thesis is concerned with the possibilities of increasing the power density of high-power dc-dc converters with galvanic isolation. Three cornerstones for reaching high power densities are identified as: size reduction of passive components, reduction of losses particularly in active components

  6. DC/DC converters for integration of double-layer condensers in onboard power supply; DC/DC-Wandler zur Einbindung von Doppelschichtkondensatoren in das Fahrzeugenergiebordnetz

    Energy Technology Data Exchange (ETDEWEB)

    Polenov, Dieter

    2010-01-15

    The paper discusses DC/DC converters for integration of double layer condensers into the onboard power system. First, requirements on DC/DC converters are listed and compared on the basis of three exemplary applications. A DC/DC converter concept is developed for decoupling transient high-power loads like electric steering systems. Three different topologies are compared using a specially developed method in order to find the best solution for the given application. In order to establish adequate criteria for selecting the switching frequency and inductivities of storage throttles, the influence of the trottle power change on the switching characteristics of the MOSFETs and on certain ranges of EMP interference emissions is investigated. As methods of optimising the operation of the synchronous rectifiers, parallel connection of Schottky diodes and synchronous rectifiers as well as the variation of the shut-off dead times of synchronous rectifiers were investigated. Further, a concept for converter control was developed in consideration of the intended application and topology. Finally, selected aspects for implementation of the DC/DC converter concept are presented as well as the results of experimental investigations.

  7. DC-based magnetic field controller

    Science.gov (United States)

    Kotter, D.K.; Rankin, R.A.; Morgan, J.P.

    1994-05-31

    A magnetic field controller is described for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a Hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage. 1 fig.

  8. Modelling of flow phenomena during DC casting

    NARCIS (Netherlands)

    Zuidema, J.

    2005-01-01

    Modelling of Flow Phenomena during DC Casting Jan Zuidema The production of aluminium ingots, by semi-continuous casting, is a complex process. DC Casting stands for direct chill casting. During this process liquid aluminium transforms to solid aluminium while cooling down. This is not an

  9. DC-based magnetic field controller

    Science.gov (United States)

    Kotter, Dale K.; Rankin, Richard A.; Morgan, John P,.

    1994-01-01

    A magnetic field controller for laboratory devices and in particular to dc operated magnetic field controllers for mass spectrometers, comprising a dc power supply in combination with improvements to a hall probe subsystem, display subsystem, preamplifier, field control subsystem, and an output stage.

  10. Analysis of a Hybrid DC Comparator

    Directory of Open Access Journals (Sweden)

    Li Web

    2006-06-01

    Full Text Available The traditional controllable saturation reactor (CSR consists of single toroidal core, DC (direct current controlled loop (including DC controlled winding and DC biasing source and AC (alternating current excitation loop (including excitation winding and AC source. A detection winding and secondary winding are added up to the CSR configuration and form a hybrid DC comparator. The excitation current is asymmetric waveform when the CSR core is commonly stimulated by both AC and DC biasing sources, which just is the fundamental characteristic for the proposed comparator. Research shows the terminal voltage of the detection winding is asymmetric waveform when the secondary winding of the comparator is open and the CSR core is stimulated both by AC and DC biasing sources. Both theory analysis and experiment verify the feasibility of the differential RMS (root-mean-square between positive and negative half waves of the terminal voltage from the detection winding fitting for the feedback variance to balance DC biasing magnetic potential and form a self-balancing comparator. The zero-flux technique that the primary ampere-turn is equal to the secondary is the function base for the comparator. The operation details of the comparator including the control characteristics both of open-loop and close loop, the satiability judgment criterion, static error property and test range are introduced. The experimental results testify to the truth of the principle of the proposed DC comparator.

  11. Control and dynamic analysis of a parallel-connected single active bridge DC-DC converter for DC-grid wind farm application

    DEFF Research Database (Denmark)

    Park, Kiwoo; Chen, Zhe

    2015-01-01

    This study presents a control strategy and its dynamic analysis of a high-power dc-dc converter, which is constructed with the parallel-connected single active bridge (SAB) dc-dc converters for dc-grid wind farm applications. The structural and operational characteristics of the SAB dc-dc convert...... for dc-grid wind farm applications, an input voltage control method based on the PI control will be introduced and the dynamics of the overall system will be analysed. The analysis results are to be verified by means of simulations and experiments.......This study presents a control strategy and its dynamic analysis of a high-power dc-dc converter, which is constructed with the parallel-connected single active bridge (SAB) dc-dc converters for dc-grid wind farm applications. The structural and operational characteristics of the SAB dc-dc converter...... have several advantages for high-power applications, and the modular concept of the parallel-connected converter is highly beneficial especially for offshore wind farm applications in terms of maintenance cost and fault tolerance. To justify the feasibility of the parallel-connected SAB dc-dc converter...

  12. 77 FR 39446 - Draft Parachute Landing Area Standards

    Science.gov (United States)

    2012-07-03

    ... Avenue SW., AAS-100, Room 621, Washington, DC 20590. Fax: (202) 267-3688. FOR FURTHER INFORMATION CONTACT... sponsors that are holders of Airport Operating Certificates issued under 14 CFR part 139) to comply with... cited reasons of safety and/or efficiency and have been generally reluctant to allow the establishment...

  13. 78 FR 65107 - Loans in Areas Having Special Flood Hazards

    Science.gov (United States)

    2013-10-30

    ..., 400 7th Street SW., Washington, DC. For security reasons, the OCC requires that visitors make an appointment to inspect comments. You may do so by calling (202) 649- 6700. Upon arrival, visitors will be... satisfaction of the mandatory flood insurance purchase requirement, described above. Section 102(b) of the FDPA...

  14. A Component-Reduced Zero-Voltage Switching Three-Level DC-DC Converter

    DEFF Research Database (Denmark)

    Qin, Zian; Pang, Ying; Wang, Huai

    2016-01-01

    The basic Zero-Voltage Switching (ZVS) three-level DC-DC converter has one clamping capacitor to realize the ZVS of the switches, and two clamping diodes to clamp the voltage of the clamping capacitor. In order to reduce the reverse recovery loss of the diode as well as its cost, this paper...... proposes to remove one of the clamping diodes in basic ZVS three-level DC-DC converter. With less components, the proposed converter can still have a stable clamping capacitor voltage, which is clamped at half of the dc link voltage. Moreover, the ZVS performance will be influenced by removing the clamping...

  15. Reproductive Health Knowledge among African American Women Enrolled in a Clinic-Based Randomized Controlled Trial to Reduce Psychosocial and Behavioral Risk: Project DC-HOPE.

    Science.gov (United States)

    Backonja, Uba; Robledo, Candace A; Wallace, Maeve E; Flores, Katrina F; Kiely, Michele

    2016-01-01

    Washington, DC, has among the highest rates of sexually transmitted infections and unintended pregnancy in the United States. Increasing women's reproductive health knowledge may help to address these reproductive health issues. This analysis assessed whether high-risk pregnant African American women in Washington, DC, who participated in an intervention to reduce behavioral and psychosocial risks had greater reproductive health knowledge than women receiving usual care. Project DC-HOPE was a randomized, controlled trial that included pregnant African American women in Washington, DC, recruited during prenatal care (PNC). Women in the intervention group were provided reproductive health education and received tailored counseling sessions to address their psychosocial and behavioral risk(s) (cigarette smoking, environmental tobacco smoke exposure, depression, and intimate partner violence). Women in the control group received usual PNC. Participants completed a 10-item reproductive knowledge assessment at baseline (n = 1,044) and postpartum (n = 830). Differences in total reproductive health knowledge scores at baseline and postpartum between groups were examined via χ(2) tests. Differences in postpartum mean total score by group were assessed via multiple linear regression. Women in both groups and at both time points scored approximately 50% on the knowledge assessments. At postpartum, women in the intervention group had higher total scores compared with women receiving usual care (mean 5.40 [SD 1.60] vs. 5.03 [SD 1.53] out of 10, respectively; p reproductive health knowledge, overall scores remained low. Development of interventions designed to impart accurate, individually tailored information to women may promote reproductive health knowledge among high-risk pregnant African American women residing in Washington, DC. Published by Elsevier Inc.

  16. 76 FR 81011 - Notice of Final Federal Agency Actions on Proposed Light Rail Project in Washington

    Science.gov (United States)

    2011-12-27

    .... Wetlands and Water Resources: Clean Water Act, 33 U.S.C. 1251- 1377 ; Coastal Zone Management Act ; Land... applies. FOR FURTHER INFORMATION CONTACT: Pete Jilek, Urban Area Engineer, Federal Highway [email protected] . The FHWA Washington Division Urban Area Engineer's regular office hours are between 6 a.m...

  17. 76 FR 46890 - Notice of Final Federal Agency Actions on Proposed Highway in Washington

    Science.gov (United States)

    2011-08-03

    .... Wetlands and Water Resources: Clean Water Act, 33 U.S.C. 1251- 1377 (Section 404, Section 401, Section 319... applies. FOR FURTHER INFORMATION CONTACT: Pete Jilek, Urban Area Engineer, Federal Highway [email protected] The FHWA Washington Division Urban Area Engineer's regular office hours are between 6 a.m...

  18. Metropolitan Washington Area Water Supply Study. Appendix F. Structural Alternatives.

    Science.gov (United States)

    1983-09-01

    ii**~f*.. ........................................... 4m II 4. 44iii~~~~~~~i~~i4444~~~~ 44. .44444 444 444444444444 444444i44 J J *~~ uA1 .CA 4 I’s

  19. Southwestern Washington 36 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 36-second Southwest Washington Elevation Grid provides bathymetric data in ASCII raster format of 36-second resolution in geographic coordinates. This grid is...

  20. Willapa Bay, Washington Benthic Habitats 1995 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  1. Willapa Bay, Washington Benthic Habitats 1995 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  2. Willapa Bay, Washington Benthic Habitats 1995 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  3. EAARL Topography George Washington Birthplace National Monument

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model or DEM) of George Washington Birthplace National Monument was produced from remotely-sensed,...

  4. Willapa Bay, Washington Benthic Habitats 1995 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  5. Report : public transportation in Washington State, 1984

    Science.gov (United States)

    1984-10-01

    This report is an update of the Public Transportation in Washington State publication, dated December 1981. In order to reflect the changes that have occurred since that time, this report contains the most current data obtainable. Chapter One of this...

  6. Expression of DC-SIGN and DC-SIGNRs in placentas of HIV-positive patients

    Directory of Open Access Journals (Sweden)

    Komala Pillay

    2014-09-01

    Full Text Available Background. Human dendritic cell-specific intracellular adhesion molecule-3 (ICAM3-grabbing non-integrin (DC-SIGN is a mannose-binding lectin that initiates interaction between dendritic cells and resting T-lymphocytes. DC-SIGN is highly expressed in placental tissue on dendritic cells and Hofbauer cells, and it is suggested that HIV may become adsorbed to DC-SIGN on Hofbauer cells as part of the mechanism of mother-to-child HIV transmission. A possible mechanism of transfer of the virus from the Hofbauer cells to the fetus is the subsequent adsorption to DC-SIGN-related molecules (DC-SIGNRs, present on immediately adjacent capillary vascular endothelium. However, data on DC-SIGN and DC-SIGNR expression in the placenta are few.Methods. Forty term placentas from HIV-positive mothers and 21 term placentas from HIV-negative mothers underwent immunohistochemistry staining for DC-SIGN and DC-SIGNR expression. Five random sets of 10 villi were assessed, and the average number of positive cells were counted in each case. In addition, where possible, maternal and cord blood viral loads and maternal CD4+ counts were performed in the HIV-positive group only.Results. The median maternal CD4+ count was 377 cells/µl and 27% of participants had undetectable viral loads; the median detectable viral load was 3.72 log. Most (97% of the cord bloods tested in infants from HIV-positive mothers had lower than detectable viral loads. HIV-positive cases had significantly greater expression of both DC-SIGNRs (median values in HIV-positive cases, 14.5 positive cells/10 villi (pc/10villi, compared with 11 pc/10villi in HIV-negative cases, p=0.020 and DC-SIGN (median value in HIV-positive cases, 26.5 pc/10villi, compared with 23 pc/10villi in HIV-negative cases, p=0.037. DC-SIGNR expression was also noted in Hofbauer cells and decidual macrophages in addition to endothelium (reported currently. There was no difference in expression of DC-SIGN and DC-SIGNRs in patients

  7. DC-Compensated Current Transformer †

    Science.gov (United States)

    Ripka, Pavel; Draxler, Karel; Styblíková, Renata

    2016-01-01

    Instrument current transformers (CTs) measure AC currents. The DC component in the measured current can saturate the transformer and cause gross error. We use fluxgate detection and digital feedback compensation of the DC flux to suppress the overall error to 0.15%. This concept can be used not only for high-end CTs with a nanocrystalline core, but it also works for low-cost CTs with FeSi cores. The method described here allows simultaneous measurements of the DC current component. PMID:26805830

  8. Studi Komparasi Fungsi Keanggotaan Fuzzy sebagai Kontroler Bidirectional DC-DC Converter pada Sistem Penyimpan Energi

    Directory of Open Access Journals (Sweden)

    Eka Prasetyono

    2015-09-01

    Full Text Available Bidirectional DC-DC converter is needed in the energy storage system. The converter topology used in this paper was a non-isolated bidirectional DC-DC buck-boost converter. This converter worked in two ways, which the charging mode stored energy into battery when load current was less than nominal main DC current (set point and discharging mode transferred energy from battery to the load when its current exceeded set point value. Both of these modes worked automatically according to the load current. The charging and discharging currents were controlled by fuzzy logic controller which was implemented on microcontroller ARM Cortex-M4F STM32F407VG. This paper compares two types of fuzzy membership function (triangular and sigmoid in controlling bidirectional DC-DC converter. The results showed that fuzzy logic controller with triangle membership function and sigmoid as control bidirectional DC-DC converter had no significant different response, both had an average error for charging and discharging process under 4% with ripple current on the main DC bus around 0.5%. The computing time of program for fuzzy logic controller with triangular membership functions had 19.01% faster than sigmoid, and fuzzy logic computation time on a microcontroller with hardware floating point was 60% faster than software floating point.

  9. Mapping and Modeling Land Use Change in the Washington-Baltimore Metropolitan Region 1986-2030

    Science.gov (United States)

    Jantz, C. A.; Goetz, S. J.; Smith, A. J.

    2002-05-01

    This research describes an effort to predict the spatial extent of urban development in the Washington, DC-Baltimore region out to 2030, prompted by a need to evaluate the impacts of different regional environmental conservation policies. This investigation is especially relevant to the region since it allows an assessment of the impacts of land use controls, such as "Smart Growth" strategies, on environmental quality and ecosystem health. Given its success with regional scale simulation and its ability to incorporate different levels of land protection through an "excluded" layer, the SLEUTH (slope, land use, excluded, urban extent, transportation, hillshade) model was adopted for this project and focused on a 45 year time period (1986-2030). Using new techniques to map impervious surfaces with Landsat TM imagery we developed a time series of urban development from 1986-2000. SLEUTH was calibrated using the impervious data set, along with other input layers such as areas excluded from development. In conjunction with the Chesapeake Bay Foundation, three alternative growth scenarios were defined for which future urban extent in 2030 would be predicted. The current trends scenario reflects smart growth and conservation policies that are currently in place, as well as major planned development and transportation improvements. The managed growth (moderate protection) scenario reflects a stronger commitment to focused growth (e.g. priority funding areas) and resource protection (e.g. riparian zones). The third scenario, managed growth with maximum protection, reflects a more stringent set of policies targeted toward limited growth and natural resource protection. Although a relatively simple model, SLEUTH was found to have several advantages for modeling regional growth. Because the data input requirements are not extensive, it was possible to prepare consistent and high-quality data sets for the entire study area. In addition, the ability of the user to modify the

  10. A Double Phase-Shift Control Strategy for A Full-Bridge Three-Level DC/DC Converter

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Gong, Zheng

    2016-01-01

    In this paper, a double phase-shift control strategy is proposed for the full-bridge three-level (FBTL) DC/DC converter applied into DC distribution systems with the medium DC bus voltage. By utilizing the proposed control strategy, the voltage change rate dv/dt and voltage stress of the transfor......In this paper, a double phase-shift control strategy is proposed for the full-bridge three-level (FBTL) DC/DC converter applied into DC distribution systems with the medium DC bus voltage. By utilizing the proposed control strategy, the voltage change rate dv/dt and voltage stress...

  11. NAMMA DC-8 DROPSONDE V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The DC-8 dropsonde system uses an integrated, highly accurate, GPS-located atmospheric profiling dropsonde, which measures and records current atmospheric conditions...

  12. GRIP DC-8 DROPSONDE V3

    Data.gov (United States)

    National Aeronautics and Space Administration — The GRIP DC-8 Dropsonde V3 dataset consists of atmospheric pressure, dry-bulb temperature, dew point temperature, relative humidity, wind direction, wind speed, and...

  13. Early Oscillation Detection for Hybrid DC/DC Converter Fault Diagnosis

    Science.gov (United States)

    Wang, Bright L.

    2011-01-01

    This paper describes a novel fault detection technique for hybrid DC/DC converter oscillation diagnosis. The technique is based on principles of feedback control loop oscillation and RF signal modulations, and Is realized by using signal spectral analysis. Real-circuit simulation and analytical study reveal critical factors of the oscillation and indicate significant correlations between the spectral analysis method and the gain/phase margin method. A stability diagnosis index (SDI) is developed as a quantitative measure to accurately assign a degree of stability to the DC/DC converter. This technique Is capable of detecting oscillation at an early stage without interfering with DC/DC converter's normal operation and without limitations of probing to the converter.

  14. The Topologies Research of a Soft Switching Bidirectional DC/DC Converter

    DEFF Research Database (Denmark)

    Zhang, Qi; Zhang, Yongping; Sun, Xiangdong

    2017-01-01

    A soft-switching solution implemented to the traditional bidirectional DC/DC converter is developed. The soft-switching cell, which composed of three auxiliary switches, one resonant capacitor and one resonant inductor, is equipped in the traditional bidirectional DC/DC converter to realize circuit...... circle. And the proposed topology of bidirectional soft-switching dc-dc converter(TASBC) performs ideal soft switching at boost operations. The characteristics of the proposed converter has been verified by MATLAB simulations and experimental results....... from a hard turning off process in one of the auxiliary switches, while the others experience the soft operation. As for the other method, the zero voltage or zero current transmissions in all switches are realized, however, the relative higher but fixed conduction losses are introduced by the resonant...

  15. Modelling and Simulation of Digital Compensation Technique for dc-dc Converter by Pole Placement

    Science.gov (United States)

    Shenbagalakshmi, R.; Sree Renga Raja, T.

    2015-09-01

    A thorough and effective analysis of the dc-dc converters is carried out in order to achieve the system stability and to improve the dynamic performance. A small signal modelling based on state space averaging technique for dc-dc converters is carried out. A digital state feedback gain matrix is derived by pole placement technique in order to achieve the stability of a completely controllable system. A prediction observer for the dc-dc converters is designed and a dynamic compensation (observer plus control law) is provided using separation principle. The output is very much improved with zero output voltage ripples, zero peak overshoot, and much lesser settling time in the range of ms and with higher overall efficiency (>90 %).

  16. Optimized photovoltaic generator-water electrolyser coupling through a controlled DC-DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Valverde, R.; Miguel, C.; Urbina, A. [Universidad Politecnica de Cartagena, Departamento de Electronica, Tecnologia de Computadoras y Proyectos, Plaza del Hospital, 1, Cartagena, 30203 Murcia (Spain); Martinez-Bejar, R. [Universidad de Murcia, Departamento de Ingenieria de la Informacion y las Comunicaciones, Facultad de Informatica, Campus de Espinardo, 30071 Murcia (Spain)

    2008-10-15

    The coupling of a photovoltaic generator and an electrolyser is one of the most promising options for obtaining hydrogen from a renewable energy source. Both are well known technologies, however, since the high variability of the solar radiation, an efficient coupling still presents some challenges. Direct or through a DC-DC converter couplings are the options in isolated applications. In this work, three models, respectively, for a photovoltaic (PV) generator, a controlled DC-DC converter and a complete proton exchange membrane (PEM) electrolyser have been designed by using Matlab/Simulink. A PV-electrolyser specific algorithm to search for the optimum and safe working point for both elements is presented. Simulation results demonstrate that the use of a controlled DC-DC converter with the proposed algorithm shows better adaptability to the variable radiation conditions than the other coupling options. Therefore, it leads to a better compliance between the electrolyser and the sizing of the PV generator. (author)

  17. Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1

    Science.gov (United States)

    Lee, F. C.; Mahmoud, M. F.; Yu, Y.

    1980-01-01

    The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.

  18. dc illusion and its experimental verification

    Science.gov (United States)

    Liu, Min; Lei Mei, Zhong; Ma, Xiang; Cui, Tie Jun

    2012-07-01

    Based on the transformation optics method, we propose a dc illusion device, which can transform a metallic object into a magnified dielectric object using anisotropic conducting materials. Utilizing the analogy between electric conductivities and resistor networks, we design and fabricate the device using metal film resistors. The practical measurement data agree very well with simulation results. The proposed dc illusion device is easy to process and measure, and thus has potential applications in various sectors.

  19. Annual scientific meeting--American Headache Society Washington 2011--highlights.

    Science.gov (United States)

    Purdy, R Allan

    2012-05-01

    The 53rd Annual Scientific Meeting of the American Headache Society was held in Washington from June 2 to 5, 2011. Important clinical and basic science information was presented at this meeting. This is a review of the highlights of that meeting dealing in many areas of headache medicine. Once again, this meeting, which is the premier scientific meeting of the American Headache Society, provided lots of new and exciting information about multiple facets of migraine headache and other disorders. © 2012 American Headache Society.

  20. Relations between ac-dc components and optical path length in photoplethysmography.

    Science.gov (United States)

    Lee, Chungkeun; Sik Shin, Hang; Lee, Myoungho

    2011-07-01

    Photoplethysmography is used in various areas such as vital sign measurement, vascular characteristics analysis, and autonomic nervous system assessment. Photoplethysmographic signals are composed of ac and dc, but it is difficult to find research about the interaction of photoplethysmographic components. This study suggested a model equation combining two Lambert-Beer equations at the onset and peak points of photoplethysmography to evaluate ac characteristics, and verified the model equation through simulation and experiment. In the suggested equation, ac was dependent on dc and optical path length. In the simulation, dc was inversely proportionate to ac sensitivity (slope), and ac and optical path length were proportionate. When dc increased from 10% to 90%, stabilized ac decreased from 1 to 0.89 ± 0.21, and when optical path length increased from 10% to 90%, stabilized ac increased from 1 to 1.53 ± 0.40.