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Sample records for research washington dc

  1. 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.

  2. 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

  3. Needs Assessment of the Healthcare Sector in the Washington, D.C., Metropolitan Area. Research Report. Business Needs Assessment Study.

    Science.gov (United States)

    Northern Virginia Community Coll., Annandale. Office of Institutional Research.

    According to the U.S. Bureau of Labor Statistics, the growing population of elderly citizens will result in an increased demand for healthcare services that will rise for a full 50 years. This study assesses the need for healthcare sector workers in the Washington, D.C. metropolitan area. Information on the skills, education, and experience that…

  4. 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.

  5. 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...

  6. 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.

  7. Spacelab ready for transport to Washington, DC

    Science.gov (United States)

    1998-01-01

    Spacelab is wrapped and ready for transport to the National Air and Space Museum in Washington, DC. Spacelab was designed by the European Space Agency (ESA) for the Space Shuttle program and first flew on STS-9 in November 1983. Its final flight was the STS-90 Neurolab mission in April 1998. A sister module will travel home and be placed on display in Europe. 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.

  8. Early Restoration Public Meeting, Washington, DC | NOAA Gulf Spill

    Science.gov (United States)

    benefit injured marshes, coastal dune and nearshore habitats, oysters, and human uses (on water recreation . Department of Commerce Herbert Hoover Building Auditorium 1401 Constitution Ave., NW Washington, D.C. 20230

  9. 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.

  10. Summary of Prioritized Research Opportunities: Building America Program Planning Meeting, Washington, D.C., November 2-4, 2010

    Energy Technology Data Exchange (ETDEWEB)

    2011-02-01

    This report outlines the results of brainstorming sessions conducted at the Building America Fall 2010 planning meeting, in which research teams and national laboratories identified key research priorities to incorporate into multi-year planning, team research agendas, expert meetings, and technical standing committees.

  11. Nuclear waste - A view from Washington, DC

    International Nuclear Information System (INIS)

    Mc Cormack, M.

    1984-01-01

    The view from Washington is an optimistic one. With support of the vast amount of research, development and engineering that scientists and engineers have completed and will do in the future, this country certainly is now headed towards a successful and orderly program for handling all radioactive wastes safely and inexpensively. The high-level waste program, for instance, will require only about 2% of the cost of electricity produced from nuclear power. It is the need for the federal government to create, by law, a public corporation for handling the fuel cycle for commercial nuclear fuel. Such a Federal Nuclear Fuel Cycle Corporation (FNFCC) would handle almost all of the nuclear power fuel cycle in a manner similar to the DOE management of the fuel cycle for the weapons program. Except for the mining and milling of uranium and the fabrication of uranium (only) fuel elements, the federal government would pre-empt ownership of all facilities used in the fuel cycle and operate them by contract with private industry (as with the weapons fuel cycle). Ownership of all fissile and fertile material (and all existing and future fuel elements) would be preempted by law and vested in the FNFCC. Reprocessing fuel to extract and glassify waste for permanent geologic disposal is the most attractive method for handling spent fuel from a safety and environmental perspective. Also recycling fuel is probably more environmentally attractive than mining more uranium, especially from lower grade ores. This concept of an FNFCC has been suggested to the Administration and to some Congressional leaders. There has been no known opposition expressed, but there is some indication of a reluctance to undertake such a major problem-solving initiative in one step

  12. 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

  13. Superconductivity in Washington, D.C

    International Nuclear Information System (INIS)

    Ritter, D.

    1988-01-01

    The author provides insights into the federal government's activity in superconductors. He says the President's most important legislative proposal is a change in anti-trust laws to allow businesses to cooperate on joint production ventures. The President has also directed the Department of Energy, the Department of Commerce, the National Aeronautics and Space Administration, the National Science Foundation, and the Department of Defense to establish Superconductivity Research Centers to conduct research and disseminate information. The author says he thinks it is worthwhile to pursue the President's proposal for cooperation with Japan in superconductivity research and development. The author explains why he supports this and other key legislation related to superconductivity. He says if the United States does not do all that it can, as fast as it can, both domestically and internationally, the U.S. could lose the cutting edge of technological and commercial leadership in the latter 20th century and the 21st century. This is what superconductivity represents

  14. 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…

  15. Drilling history core hole DC-6 Hanford, Washington

    International Nuclear Information System (INIS)

    1978-06-01

    Core hole DC-6 was completed in May 1978 by Boyles Brothers Drilling Company, Spokane, Washington, under subcontract to Fenix and Scisson, 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-6. Core hole DC-6 is located within the boundary of the Hanford Site at the old Hanford town site. The Hanford Site coordinates for DC-6 are North 54,127.17 feet and West 17,721.00 feet. The surface elevation is approximately 402 feet above sea level. The purpose of core hole DC-6 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. The total depth of core hole DC-6 was 4336 feet. Core recovery was 98.4% of the total footage cored

  16. DC Rocks! Using Place-Based Learning to Introduce Washington DC's K-12 Students to the Geosciences

    Science.gov (United States)

    Mayberry, G. C.; Mattietti, G. K.

    2017-12-01

    The Washington DC area has interesting geology and a multitude of agencies that deal with the geosciences, yet K-12 public school students in DC, most of whom are minorities, have limited exposure to the geosciences. Geoscience agencies in the DC area have a unique opportunity to address this by introducing the geosciences to local students who otherwise may not have such an opportunity, by highlighting the geology in the students' "backyard," and by leveraging partnerships among DC-based geoscience-related agencies. The USGS and George Mason University are developing a project called DC Rocks, which will give DC's students an exciting introduction into the world of geoscience with place-based learning opportunities that will make geoscience relevant to their lives and their futures. Both the need in DC and the potential for lasting impact are great; the geosciences have the lowest racial diversity of all the science, technology, engineering, and math (STEM) fields, 89% of students in DC public schools are minorities, and there is no dedicated geoscience curriculum in DC. DC Rocks aims to give these students early exposure to the earth sciences, and encourage them to consider careers in the profession. DC Rocks will work with partner agencies to apply several methods that are recommended by researchers to increase the participation of minority students in the geosciences, including providing profoundly positive experiences that spark interest in the geosciences (Levine et al., 2007); increasing students' sense of belonging in the geosciences (Huntoon, et al, 2016); and place-based teaching practices that emphasize the study of local sites (Semken, 2005), such as DC's Rock Creek Park. DC Rocks will apply these methods by coordinating local geoscientists and resources to provide real-world examples of the geosciences' impact on students' lives. Through the DC Rocks website, educators will be able to request geoscience-related resources such as class presentations by

  17. Report of the Annual Scientific Sessions of the American College of Cardiology (ACC), Washington DC.

    Science.gov (United States)

    Hiro, Takafumi

    2017-05-25

    The 66 th Annual Scientific Sessions and Expo of the American College of Cardiology (ACC) were held at the Walter E. Washington Convention Center, Washington DC, from March 17 th to 19 th , 2017. This meeting offered 23 Late-Breaking Clinical Trial (LBCT) presentations, 17 Featured Clinical Research presentations with and without LBCT, and 2,572 abstracts presented in oral and poster sessions by over 2,000 experts. This report presents the highlights of this meeting, including the opening showcase, several important LBCTs and some international joint symposiums.

  18. A green roof grant program for Washington DC

    International Nuclear Information System (INIS)

    Johnson, P.A.

    2007-01-01

    The Chesapeake Bay Foundation (CBF) began its green roof demonstration project with $300,000 in funding provided by the DC Water and Sewer Authority. This paper reviewed the history of the project, its goals and early findings. The main objective was to demonstrate the technical, policy and economic feasibility of installing green roofs on commercial buildings in Washington DC and to promote green roofs as a means to manage storm water and improve water quality through the reduction of excessive runoff. The CBF has issued grants for the installation of 7 green roofs varying in size, design, location, and use. The projects included both new and existing structures designed to improve storm-water management in an urban area with significant pollution stress on the adjacent rivers. This paper provided technical, cost, and performance evaluations of each roof. A public outreach segment provided information to decision-makers to encourage more widespread replication of green roof technology throughout the metropolitan area. Much of the District of Columbia is served by a combined sewer system that becomes overloaded and discharges raw sewage into adjacent rivers during even moderately heavy rains. An average of 75 overflow events each year result in 1.5 billion gallons discharged into the Anacostia River. The installation of green roofs on buildings in the combined sewer area would retain storm water during these heavy rains and reduce the amount of overflow discharges. Apartments, as well as commercial and government buildings with mostly flat roofs are the most likely candidates for green roofs. The demonstration roofs are intended to become models, which all building owners could use as a guide for future plans for construction or re-construction to expand green roof coverage in Washington DC. It was emphasized that although such large-scale replication will take time and financial investments, it is achievable given enough political will and commercial awareness of

  19. 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

  20. Cigarette price variation around high schools: evidence from Washington DC.

    Science.gov (United States)

    Cantrell, Jennifer; Ganz, Ollie; Anesetti-Rothermel, Andrew; Harrell, Paul; Kreslake, Jennifer M; Xiao, Haijun; Pearson, Jennifer L; Vallone, Donna; Kirchner, Thomas R

    2015-01-01

    This study examines lowest cigarette prices in all tobacco retail outlets in Washington D.C. (n=750) in relation to the type and number of high schools nearby, controlling for confounders. The lowest overall and Newport menthol prices were significantly lower at outlets near public non-charter and charter schools compared with outlets near private schools. Given higher smoking prevalence and more price-sensitive youth subgroups in U.S. public schools, exposure to low prices may contribute to tobacco-related health disparities in minority and low-income populations. Tobacco taxes combined with policies to minimize the increasing use of price as a marketing tool are critical. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. 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

  2. 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

  3. An Analysis of Wintertime Winds in Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    Berg, Larry K.; Allwine, K Jerry

    2006-06-20

    This report consists of a description of the wintertime climatology of wind speed and wind direction around the National Mall in Washington, D.C. Meteorological data for this study were collected at Ronald Reagan Washington National Airport (Reagan National), Dulles International Airport (Dulles), and a set of surface meteorological stations that are located on a number of building tops around the National Mall. A five-year wintertime climatology of wind speed and wind direction measured at Reagan National and Dulles are presented. A more detailed analysis was completed for the period December 2003 through February 2004 using data gathered from stations located around the National Mall, Reagan National, and Dulles. Key findings of our study include the following: * There are systematic differences between the wind speed and wind direction observed at Reagan National and the wind speed and wind direction measured by building top weather stations located in the National Mall. Although Dulles is located much further from the National Mall than Reagan National, there is better agreement between the wind speed and wind direction measured at Dulles and the weather stations in the National Mall. * When the winds are light (less than 3 ms-1 or 7 mph), there are significant differences in the wind directions reported at the various weather stations within the Mall. * Although the mean characteristics of the wind are similar at the various locations, significant, short-term differences are found when the time series are compared. These differences have important implications for the dispersion of airborne contaminants. In support of wintertime special events in the area of the National Mall, we recommend placing four additional meteorological instruments: three additional surface stations, one on the east bank of the Potomac River, one south of the Reflecting Pool (to better define the flow within the Mall), and a surface station near the Herbert C. Hoover Building; and wind

  4. 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...

  5. Crash barrier research and application in the Netherlands. Paper presented at 52nd HRB Annual Meeting, 22-26 January 1973, Washington, D.C.

    NARCIS (Netherlands)

    Paar, H.G.

    1973-01-01

    Research was carried out by the SWOV into the most suitable crash barriers for soft soil and for bridges. The research was based on the following requirements: (1) sufficient strength and height; (2) the ability to deflect sufficiently without discontinuities; (3) very gradual deflection and

  6. Researching College- and Career Ready Standards to Improve Student Outcomes: Technical Working Group Meeting. Meeting Summary (Washington, DC, August 19-20, 2013)

    Science.gov (United States)

    Institute of Education Sciences, 2013

    2013-01-01

    In August, IES worked with the National Science Foundation and the Eunice Kennedy Shriver National Institute of Child Health and Human Development to convene a technical working group to discuss research objectives related to college- and career-ready standards in English language arts and mathematics. Forty people (including researchers,…

  7. Welcome address to 30th international meeting on Reduced Enrichment for Research and Test Reactors, 6 October 2008, Washington, D.C., USA

    International Nuclear Information System (INIS)

    Sokolov, Y.

    2008-01-01

    The RERTR meetings, of course, have a special role among our activities. They are important not only for what is presented in the formal technical sessions, but also for what takes place in the informal gatherings, side meetings, and personal encounters. The IAEA also has participated as an observer in the International Fuel Development Working Group, a highly important effort that is overseeing the multinational cooperative research and development effort for very high density LEU fuel. Remarkable achievements of GTRI are the conversion to LEU or final shutdown prior to conversion of 62 research reactors, the return to the United States of more than 1100 kg of spent HEU fuel and more than 1800 kg of spent LEU fuel and the return to Russia of more than 600 kg of spent and fresh HEU fuel. But while much has been achieved so far, vulnerabilities remain. HEU continues to be used for military purposes in a number of States; about 150 civilian and military research reactors are still using HEU and important quantities of fresh; and spent HEU fuel continues to be stored in different countries. All this calls for continued efforts, with a sense of urgency and more coherent global action. Some of the measures that might be taken are as follows: The countries involved should join forces to step up their efforts towards minimizing and eventually eliminating the civilian and in due course the military use of HEU. Financing and other incentives should be made available where needed to assist countries with conversion operations. All countries should agree to stop producing fissile material for use in nuclear weapons. The elements are already in place for such an agreement, in the form of the proposed Fissile Material Cut-off Treaty. It is high time to negotiate and conclude such a treaty. To build confidence, countries with civilian and military HEU stockpiles should declare the size of those stockpiles and publish a schedule under which the remaining HEU will be verifiably

  8. Effects of the 2002 sniper attacks on the homeless population in Washington, DC.

    Science.gov (United States)

    Fullerton, Carol S; Gifford, Robert K; Flynn, Brian W; Peterson, Karen M; Ahearn, Frederick L; Donaldson, Linda Plitt; Ursano, Robert J

    2009-10-01

    Despite the prevalence of homelessness, this population has rarely been included in disaster and terrorism planning. To better understand the mental health needs of the homeless during a terrorist event and to highlight the need to address methodological limitations in research in this area, we examined responses to the October 2002 Washington, DC, sniper attacks. We interviewed 151 homeless individuals 1 year after the Washington, DC, sniper attacks. The majority (92.7%) was aware of the sniper events; 84.1% stayed informed through the media and 72.7% had someone to turn to for emotional support. Almost half (44%) reported identification with victims and 41% increased substance use during the attacks. More than half (61.7%) felt extremely frightened or terrified and 57.6% reported high perceived threat. Females, nonwhites, and participants with less than a high school education experienced greater threat. Women, nonwhites, and younger (homeless population may be difficult to reach or reluctant to comply with public health programs. Addressing barriers to health care in vulnerable groups is critical to effective public health disaster response.

  9. Drug Treatment in New York City and Washington, D.C.: Followup Studies.

    Science.gov (United States)

    Burt Associates, Inc., Bethesda, MD.

    This report assesses the experiences of clients who had contact with or received drug abuse treatment from programs of the Addiction Services Agency in New York City and the Narcotics Treatment Administration in Washington, D.C. during the early 1970's. To answer the questions of what happens to former clients once they leave drug treatment…

  10. 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...

  11. 75 FR 1406 - National Mall and Memorial Parks, Washington, DC; Notice of Availability of an Environmental...

    Science.gov (United States)

    2010-01-11

    ... Washington, DC. The National Mall Plan is a long-range management plan that focuses on the use and... Spain, Project Executive. Before including your address, phone number, e-mail address, or other personal... Impact Statement. FOR FURTHER INFORMATION CONTACT: Susan Spain, Project Executive, National Mall Plan at...

  12. 78 FR 37104 - Establishment of Area Navigation (RNAV) Routes; Washington, DC

    Science.gov (United States)

    2013-06-20

    ...-0081; Airspace Docket No. 12-AEA-5] RIN 2120-AA66 Establishment of Area Navigation (RNAV) Routes... Register approves this incorporation by reference action under 1 CFR part 51, subject to the annual... establishing five RNAV routes in the Washington, DC area (78 FR 29615). Subsequent to publication, it was...

  13. 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...

  14. Making Difficult History Public: The Pedagogy of Remembering and Forgetting in Two Washington DC Museums

    Science.gov (United States)

    Segall, Avner

    2014-01-01

    In this article, Avner Segall explores some pedagogical processes in the context of two museums in Washington, DC, that focus on difficult knowledge, the National Museum of the American Indian (NMAI) and the United States Holocaust Memorial Museum. In doing so, Segall's aim is not to explore the museums as a whole or provide a comprehensive…

  15. 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…

  16. 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...

  17. 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...

  18. 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...

  19. Science meets public service in Washington, D.C.

    Science.gov (United States)

    Vasavada, Ashwin R.

    Same planet, different worlds—that's how many scientists see the relationship between science and government. Yet science and technology have become so infused into society that those worlds are colliding. Today, a number of national issues share a strong connection to science, from stem cells to climate change and energy to bioterrorism. For scientists who can adapt to the culture of politics, working in the collision zone can be an exciting and rewarding way to spend a year or even a career.This past year, I was one of 35 scientists in Washington serving as Congressional Science and Technology Fellows, sponsored by a number of scientific societies, including AGU. The Fellows vary widely in age and carry resumes listing Ph.D.s in not only physics, biology, and chemistry but also in Earth science, food safety, psychology, and veterinary medicine. With a group like that, weekly lunches and happy hours become the kind of broadening experience that one rarely gets in focused academic departments. And then there's the politics.

  20. Advances in Exposure Science (Washington, DC Modernized TSCA meeting)

    Science.gov (United States)

    I am describing current research from the Chemical Safety for Sustainability research program's Rapid Exposure and Dosimetry project that relates to predicting human exposure to environmental chemicals for thousands of chemicals.

  1. Enhancement of the Monet/Atonet Washington DC Network

    National Research Council Canada - National Science Library

    Jackel, Janet

    2003-01-01

    ... Internet research networks. The report also describes research in the use of hierarchical multiplexing approaches for more efficient use of multi-wavelength networks and enhancements to the MONET Network Control & Management System...

  2. 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.

  3. Research borehole drilling activity for boreholes DH-18, DH-19, DC-12, DC-13, DC-14, DC-15, and deepening of existing borehole DC-7

    International Nuclear Information System (INIS)

    1979-09-01

    This report is an environmental evaluation of the impacts of proposed borehole drilling activities at the Hanford Site, northwest of Richland, Washington. The proposed action is to drill six research boreholes ranging in depth from 137 to 1372 meters (m) [250 to 4500 +- feet (ft)]. In addition, an existing borehole (DC-7) will be extended from 1249 to 1524 m (4099 to 5000 +- ft). The purpose of the US Department of Energy's (DOE) borehole drilling activities is to collect data on in situ rock formations that are considered potentialy suitable for nuclear waste repositories. The technical program efforts necessary to identify and qualify specific underground waste facility sites in candidate rock formations include geologic and hydrologic studies (seismicity and tectonics, rock structure and stratigraphy, lithology, etc.). Borehole drilling is an integral part of the geological studies and is essential to a thorough understanding of potentially suitable geologic formations. The purpose of the proposed drilling activities is to obtain data for evaluating Columbia River basalts that are being evaluated by the National Waste Terminal Storage (NWTS) Program to determine their suitability potential for nuclear waste repositories. Unavoidable impact to the environment is limited primarily to the clearing of land needed for access and drilling operations. Considerations exercised during site preparation, drilling, and subsequent site restoration will limit modification of the natural environment to the minimum required for accomplishment of test objectives

  4. 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

  5. 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.

  6. National Nuclear Waste Policy Act of 1981. Hearings before the Committee on Environment and Public Works, United States Senate, Ninety-Seventh Congress, First Session on S. 1662, October 31, 1981, Richland, Washington; November 9, 1981, Washington, DC

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    Hearings were held on October 31, 1981 in Richland, Washington and on November 9, 1981 in Washington, DC to discuss the effort in S. 1662 to establish a national policy and an environmentally acceptable program for managing nuclear wastes from domestic commercial activities. The Richland hearing was held in recognition that Washington State will bear the major impact of the legislation. Witnesses at the Washington, DC hearing included officials from states that are potential sites for radioactive waste storage and disposal facilities. The hearing record includes the testimony of 16 witnesses in Richland and seven in Washington, DC, followed by a reprint of S. 1662 and additional material submitted for the record

  7. 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

  8. 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!

  9. HySafe research priorities workshop report Summary of the workshop organized in cooperation with US DOE and supported by EC JRC in Washington DC November 10-11 2014.

    Energy Technology Data Exchange (ETDEWEB)

    Jay Keller; Laura Hill; Kristian Kiuru; Groth, Katrina M.; Hecht, Ethan; Will James

    2016-03-01

    The HySafe research priorities workshop is held on the even years between the International Conference on Hydrogen Safety (ICHS) which is held on the odd years. The research priorities workshop is intended to identify the state-of-the-art in understanding of the physical behavior of hydrogen and hydrogen systems with a focus on safety. Typical issues addressed include behavior of unintended hydrogen releases, transient combustion phenomena, effectiveness of mitigation measures, and hydrogen effects in materials. In the workshop critical knowledge gaps are identified. Areas of research and coordinated actions for the near and medium term are derived and prioritized from these knowledge gaps. The stimulated research helps pave the way for the rapid and safe deployment of hydrogen technologies on a global scale. To support the idea of delivering globally accepted research priorities for hydrogen safety the workshop is organized as an internationally open meeting. In attendance are stakeholders from the academic community (universities, national laboratories), funding agencies, and industry. The industry participation is critically important to ensure that the research priorities align with the current needs of the industry responsible for the deployment of hydrogen technologies. This report presents the results of the HySafe Research Priorities Workshop held in Washing- ton, D.C. on November 10-11, 2014. At the workshop the participants presented updates (since the previous workshop organized two years before in Berlin, Germany) of their research and development work on hydrogen safety. Following the workshop, participants were asked to provide feedback on high-priority topics for each of the research areas discussed and to rank research area categories and individual research topics within these categories. The research areas were ranked as follows (with the percentage of the vote in parenthesis): 1. Quantitative Risk Assessment (QRA) Tools (23%) 2. Reduced Model

  10. Survey about pedestrian safety and attitudes toward automated traffic enforcement in Washington, D.C.

    Science.gov (United States)

    Cicchino, Jessica B; Wells, Joann K; McCartt, Anne T

    2014-01-01

    Pedestrians represent more than one third of all traffic deaths in Washington, D.C. The District plans to expand its long-standing automated traffic enforcement program in 2013 from speed and red light cameras to cameras to enforce pedestrian right-of-way laws at crosswalks and stop sign laws. This study collected information on the opinions, behaviors, and knowledge of D.C. residents related to camera enforcement and pedestrian safety issues. A telephone survey of 801 adult D.C. residents was conducted in November 2012 with approximately equal numbers of respondents in each of D.C.'s eight wards. Quotas were used to ensure that the sample was representative of the demographic characteristics of adults in each ward. For analyses combining responses across the wards, data were weighted to correspond with the demographic characteristics of adults in the city. Most respondents believed that drivers speeding, running red lights, running stop signs, and not stopping for pedestrians are serious threats to their safety. Respondents strongly supported the speed and red light camera programs, with 76 percent of respondents favoring speed cameras and 87 percent favoring red light cameras. Support was more limited for the camera enforcement that was not yet in place at the time of the survey, with 50 percent of respondents favoring stop sign cameras and 47 percent of respondents favoring crosswalk cameras. Twenty-four percent of respondents had not driven a car in D.C. in the past month, and higher proportions of these nondrivers favored speed cameras (90%), stop sign cameras (67%), and crosswalk cameras (59%) than respondents who drove in D.C. in the past month. Respondents who supported camera enforcement cited safety as their main reason. More than 9 in 10 respondents knew that D.C. law requires drivers to stop for pedestrians crossing the street in marked crosswalks at intersections without traffic signals and midblock, but only 54 percent knew that drivers must stop for

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

    Science.gov (United States)

    1982-09-01

    U.S. civil system managed by the civil administration, but it would be even easier if it were a system agreed to and Jointly financed by ICAO or some... Unicorns Park Drive 955 L’Enfant Plaza Woburn, MA 01801 Washington, D.C. 20024 84 r. C. Dennis Wright Aircraft Owners & Pilots Association P.O. Box 5800

  13. University of Washington Center for Child Environmental Health Risks Research

    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...

  14. 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.

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

    Science.gov (United States)

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

    2013-11-06

    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.

  16. Organochlorine chemical residues in Northern Cardinal (Cardinalis cardinalis) eggs from Greater Washington, DC USA

    Science.gov (United States)

    Schmitt, Christopher J.; Echols, Kathy R.; Peterman, Paul; Orazio, Carl; Grimm, Christiana; Tan, Shirlee; Diggs, Nora E.; Marra, Peter P.

    2018-01-01

    Northern Cardinal eggs from six neighborhoods near Washington DC were analyzed for organochlorine pesticides and PCBs. All compounds were detected more frequently and at higher concentrations in more heavily urbanized neighborhoods. DDT (mostly as p,pʹ-DDE) was detected in all neighborhoods. p,pʹ-DDT was typically 0.5‒16 ng/g (ww) in most suburban neighborhoods but was not detected (< 0.1 ng/g) in more rural areas; however, p,pʹ-DDT was 127‒1130 ng/g in eggs from two suburban Maryland nests and comprised 65.7% of total p,pʹ-DDT isomers in the most contaminated sample, indicating recent exposure to un-weathered DDT. Total chlordane (sum of 5 compounds) was 2‒70 ng/g; concentrations were greatest in older suburban neighborhoods. Total PCB (sum of detected congeners) was < 5‒21 ng/g. Congener patterns were similar in all neighborhoods and resembled those typical of weathered mixtures. Results indicate that wildlife remains exposed to low concentrations of legacy contaminants in suburban neighborhoods and that cardinal eggs can be used to monitor localized contamination.

  17. Quantifying the Consumptive Landscape in the Potomac Watershed Upstream From Washington DC

    Science.gov (United States)

    Kearns, M.; Zegre, N.; Fernandez, R.

    2017-12-01

    Some of the largest and fastest-growing eastern cities depend upon Appalachian headwaters for their fresh water. Today's relative abundance of water may be at risk: changes in climate and land use could alter the availability of surface water and human consumption could increase to meet the needs of a growing population and economy. Neither the supply of surface water nor the various withdrawals that support our population, irrigation, energy, and industry are distributed uniformly throughout our watersheds. This study correlates surface water withdrawals, consumptive use coefficients, and land-use/land-cover datasets to create a model for quantifying anthropogenic water consumption. The model suggests a method for downscaling and redistributing USGS county-level surface water withdrawals to 30 meter cells. Initially completed for the Potomac River watershed upstream from Washington DC's public supply intake, this approach could easily scale regionally or nationally. When combined with runoff estimates over the same landscape, the net-production or net-consumption of an area of interest may be calculated at high resolution. By better understanding the spatial relationship between hydrologic supply and demand, we can seek to improve the efficiency and security of our water resources.

  18. 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.

  19. 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.

  20. Arms control in space: workshop proceedings, Washington, DC, January 30-31, 1984

    International Nuclear Information System (INIS)

    1984-05-01

    In late 1982 and early 1983, the Subcommittee on Arms Control, Oceans, International Operations, and Environment of the Senate Committee on Foreign Relations held hearings on space weapons and arms control. To explore these issues further in a discussion format not easily achieved in hearings, Sen. Larry Pressler, Chairman of the Subcommittee, asked OTA to conduct a workshop focusing on antisatellite (ASAT) weapons as one aspect of space arms control. The workshop held in Washington, DC on January 30 and 31, 1984, provided an opportunity for technical, diplomatic, military, and policy-analysis experts to interact, think out loud, and build each other's ideas. The workshop was organized into six sessions, although issues involving anti-satellite weapons and arms control are not easily compartmentalized into distinct subject areas. Each session was introduced by a 10- or 15-minute informal oral presentation which set the stage for further discussion. This workshop proceedings volume is organized along the same divisions as the sessions, with some rearrangement

  1. Legal Immigration Status is Associated with Depressive Symptoms among Latina Transgender Women in Washington, DC

    Directory of Open Access Journals (Sweden)

    Thespina Yamanis

    2018-06-01

    Full Text Available Latina transgender women (LTW are disproportionately vulnerable to depression, although the role of immigration/documentation status (legal authority to live/work in the U.S. in depression has not been explored. LTW in Washington, DC were recruited into a cross-sectional study via convenience sampling. Most were Spanish-speaking Central American immigrants. Participants completed rapid HIV tests, and a Spanish-language survey assessing recent depressive symptoms (PHQ-2, sociodemographics, and factors from the minority stress framework: structural stressors (documentation status, stable housing, social stressors (discrimination, fear of deportation, violence and coping resources (social support, resilience. Among immigrant LTW (n = 38, 24 were undocumented. Among the undocumented, the average PHQ-2 score was 2.7, and among the documented, the average PHQ-2 score was 1.4 (p < 0.05. Undocumented LTW were significantly more likely to experience employment discrimination, recent unstable housing, and fear of deportation. Bivariate and multiple linear regressions were performed to assess the relationship between documentation status and other correlates of past two week depressive symptoms. In multivariate analysis, PHQ-2 scores were inversely associated with being documented (p < 0.01, having an income above the federal poverty level, higher friends’ social support, and increased resiliency. Documentation status is an important correlate of depressive symptoms among LTW that should be considered within the context of health interventions.

  2. VSP - Discussion: The Common Interest on Planning Hulls and Plan for Collaboration Studies between NSWC and KRISO - Washington DC

    Science.gov (United States)

    2016-03-07

    planning hulls and plan for N62909-15-1-2052 collaboration studies between NSWC and KRISO - Washington DC Sb. GRANT NUMBER N62909-15-1-2052 Sc. PROGRAM...be carried out in MASK’s facilities. We discussed common interests on planing hulls, and made plans for collaboration studies between NSWC and KRISO ...Presentation of USV project in KRISO 8/19/2015 (Wed) • Discussion of common interests about planing hu lls • Planning for collaboration studies

  3. 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.

  4. Hearings Before the Select Committee on Nutrition and Human Needs of the United States Senate, Ninety-Third Congress, First Session. Nutrition Education--1973. Part 6--Phosphate Research and Dental Decay. Hearings Held Washington, D.C., April 16, 1973.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Senate Select Committee on Nutrition and Human Needs.

    These hearings before the Select Committee on Nutrition and Human Needs of the United States Senate include testimony on the subject of research into the use of phosphates to prevent dental decay. The purpose of the hearing was to explore certain dental health questions raised during the committee's recent hearings on the Television Advertising of…

  5. Lithologic Coring in the Lower Anacostia Tidal Watershed, Washington, D.C., July 2002

    Science.gov (United States)

    Tenbus, Frederick J.

    2003-01-01

    Little is known about the volumetric flux of ground water to the lower tidal Anacostia River, or whether ground-water flow is an important component of the contaminant load in this part of the Anacostia River. The watershed is in the eastern part of Washington, D.C., and has been subjected to over 200 years of urbanization and modifications of the river channel and nearby land areas. These anthropogenic factors, along with tidal fluctuations in the river, make ground-water data collection and interpretations difficult. The U.S. Geological Survey is cooperating with the District of Columbia Department of Health, Environmental Health Administration, Bureau of Environmental Quality, Water Quality Division, in a study to assess nonpoint-source pollution from ground water into the lower tidal Anacostia River. Lithologic cores from drilling activities conducted during July 2002 in the study area have been interpreted in the context of geologic and hydrogeologic information from previous studies in the lower Anacostia tidal watershed. These interpretations can help achieve the overall project goals of characterizing ground-water flow and contaminant load in the study area. Hydrostratigraphic units encountered during drilling generally consisted of late Pleistocene to Holocene fluvial deposits overlying Cretaceous fluvial/deltaic deposits. Cores collected in Beaverdam Creek and the Anacostia River indicated high- and low-energy environments of deposition, respectively. Two cores collected near the river showed different types of anthropogenic fill underlain by low-energy deposits, which were in turn underlain by sand and gravel. A third core collected near the river consisted primarily of sand and gravel with no artificial fill.

  6. The effects of water filtration systems on fluoride: Washington, D.C. metropolitan area.

    Science.gov (United States)

    Jobson, M D; Grimm, S E; Banks, K; Henley, G

    2000-01-01

    According to the U.S. Environmental Protection Agency (EPA), approximately one in eight Americans is exposed to potentially harmful microbes, pesticides, lead, or radioactive radon whenever they drink a glass of tap water or take a shower. One reason for this exposure is that the water plants are aging or ill equipped to process the huge amounts of raw sewage and agricultural pollutants that are still being discharged into our drinking-water sources. Other compounds such as fluoride and chloride have been added to the community water supplies for health benefits. Water filtration systems are becoming more popular as people become concerned with pollutants in the public water supply and questions are being raised as to whether fluoride is affected by these filters. The aim of this pilot study was to assess the efficacy of three types of water filtration systems and to determine their impact on fluoride content of the water in the Washington, D.C. metropolitan area. One sample of water was collected daily for fourteen days, from one location. The sample was divided to use as a control and the test samples which were processed through various filter systems. With the use of a fluoride ion specific electrode, the fluoride concentration level was tested in all samples in order to determine the percentage of fluoride removed. This study was intended to prove that the water filtration systems did not affect the advantage offered by optimum water fluoride levels. The experimental samples were ascertained and compared to the control group, resulting in three of the four carbon filters showing statistically significant amounts of fluoride removed from the water. Both Reverse Osmosis and Distillation, as expected, removed the fluoride at a high rate.

  7. Washington, D.C. | Midmarket Solar Policies in the United States | Solar

    Science.gov (United States)

    development have kept SREC prices high. Recent DC solar initiatives (e.g., the Solar Advantage Plus Program ) have targeted low-income residents. Small businesses may be able to leverage resources from the DC residential and commercial customer-generators with systems powered by renewable-energy sources. DC's net

  8. Scaling of economic benefits from green roof implementation in Washington, DC.

    Science.gov (United States)

    Niu, Hao; Clark, Corrie; Zhou, Jiti; Adriaens, Peter

    2010-06-01

    Green roof technology is recognized for mitigating stormwater runoff and energy consumption. Methods to overcome the cost gap between green roofs and conventional roofs were recently quantified by incorporating air quality benefits. This study investigates the impact of scaling on these benefits at the city-wide scale using Washington, DC as a test bed because of the proposed targets in the 20-20-20 vision (20 million ft(2) by 2020) articulated by Casey Trees, a nonprofit organization. Building-specific stormwater benefits were analyzed assuming two proposed policy scenarios for stormwater fees ranging from 35 to 50% reduction for green roof implementation. Heat flux calculations were used to estimate building-specific energy savings for commercial buildings. To assess benefits at the city scale, stormwater infrastructure savings were based on operational savings and size reduction due to reduced stormwater volume generation. Scaled energy infrastructure benefits were calculated using two size reductions methods for air conditioners. Avoided carbon dioxide, nitrogen oxide (NO(x)), and sulfur dioxide emissions were based on reductions in electricity and natural gas consumption. Lastly, experimental and fugacity-based estimates were used to quantify the NO(x) uptake by green roofs, which was translated to health benefits using U.S. Environmental Protection Agency models. The results of the net present value (NPV) analysis showed that stormwater infrastructure benefits totaled $1.04 million (M), while fee-based stormwater benefits were $0.22-0.32 M/y. Energy savings were $0.87 M/y, while air conditioner resizing benefits were estimated at $0.02 to $0.04 M/y and avoided emissions benefits (based on current emission trading values) were $0.09 M-0.41 M/y. Over the lifetime of the green roof (40 years), the NPV is about 30-40% less than that of conventional roofs (not including green roof maintenance costs). These considerable benefits, in concert with current and

  9. Washington State University Algae Biofuels Research

    Energy Technology Data Exchange (ETDEWEB)

    chen, Shulin [Washington State Univ., Pullman, WA (United States). Dept. of Biological Systems Engineering; McCormick, Margaret [Targeted Growth, Inc., Seattle, WA (United States); Sutterlin, Rusty [Inventure Renewables, Inc., Gig Harbor, WA (United States)

    2012-12-29

    The goal of this project was to advance algal technologies for the production of biofuels and biochemicals by establishing the Washington State Algae Alliance, a collaboration partnership among two private companies (Targeted Growth, Inc. (TGI), Inventure Chemicals (Inventure) Inc (now Inventure Renewables Inc) and Washington State University (WSU). This project included three major components. The first one was strain development at TGI by genetically engineering cyanobacteria to yield high levels of lipid and other specialty chemicals. The second component was developing an algal culture system at WSU to produce algal biomass as biofuel feedstock year-round in the northern states of the United States. This system included two cultivation modes, the first one was a phototrophic process and the second a heterotrophic process. The phototrophic process would be used for algae production in open ponds during warm seasons; the heterotrophic process would be used in cold seasons so that year-round production of algal lipid would be possible. In warm seasons the heterotrophic process would also produce algal seeds to be used in the phototrophic culture process. Selected strains of green algae and cyanobacteria developed by TGI were tested in the system. The third component was downstream algal biomass processing by Inventure that included efficiently harvesting the usable fuel fractions from the algae mass and effectively isolating and separating the usable components into specific fractions, and converting isolated fractions into green chemicals.

  10. An assessment of solar hot water heating in the Washington, D.C. area - Implications for local utilities

    Science.gov (United States)

    Stuart, M. W.

    1980-04-01

    A survey of residential solar hot water heating in the Washington, D.C. area is presented with estimates of the total solar energy contribution per year. These estimates are examined in relation to a local utility's peak-load curves to determine the impact of a substantial increase in solar domestic hot water use over the next 20 yr in the area of utility management. The results indicate that a 10% market penetration of solar water heaters would have no detrimental effect on the utility's peak-load profile and could save several million dollars in new plant construction costs.

  11. 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.

  12. Map Sensitivity vs. Map Dependency: A Case Study of Subway Maps’ Impact on Passenger Route Choices in Washington DC

    Directory of Open Access Journals (Sweden)

    John Xu

    2017-10-01

    Full Text Available This paper addresses the key assumption in behavioral and transportation planning literature that, when people use a transit system more frequently, they become less dependent on and less sensitive to transit maps in their decision-making. Therefore, according to this assumption, map changes are much less impactful to travel decisions of frequent riders than to that of first-time or new passengers. This assumption—though never empirically validated—has been the major hurdle for transit maps to becoming a planning tool to change passengers’ behavior. This paper examines this assumption using the Washington DC metro map as a case study by conducting a route choice experiment between 30 Origin-Destination (O-D pairs on seven metro map designs. The experiment targets two types of passengers: frequent metro riders through advertisements on a free daily newspaper available at DC metro stations, and general residents in the Washington metropolitan area through Amazon Mechanical Turk, an online crowdsourcing platform. A total of 255 and 371 participants made 2024 and 2960 route choices in the respective experiments. The results show that frequent passengers are in fact more sensitive to subtle changes in map design than general residents who are less likely to be familiar with the metro map and therefore unaffected by map changes presented in the alternative designs. The work disproves the aforementioned assumption and further validates metro maps as an effective planning tool in transit systems.

  13. 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.

  14. "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).

  15. THE ROLE OF HISTORICAL AERIAL PHOTOGRAPHS IN THE REMEDIATION OF WWI CHEMICAL CONTAMINATION IN THE SPRING VALLEY SUPERFUND SITE, 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...

  16. Problems of Journalism; Proceedings of the 1975 Annual Convention of the American Society of Newspaper Editors (Washington, D.C., April 16-18, 1975).

    Science.gov (United States)

    American Society of Newspaper Editors, Easton, PA.

    This document reports the 1975 proceedings of the American Society of Newspaper Editors (ASNE) convention held in Washington, D.C., April 16-18. The contents include a list of officers and directors, past presidents of the society, and a copy of the ASNE Code of Ethics. Also contained in the document are reports on such individual sessions as…

  17. Patterns of HIV/AIDS, STI, Substance Abuse and Hepatitis Risk among Selected Samples of Latino and African-American Youth in Washington, DC

    Science.gov (United States)

    Edberg, Mark C.; Collins, Elizabeth; Harris, Meredith; McLendon, Hedda; Santucci, Patricia

    2009-01-01

    In order to address evolving risk factors among youth in Washington, DC (District of Columbia), with respect to HIV/AIDS, sexually transmitted infections (STIs), substance abuse, and hepatitis, a targeted, community-needs assessment was conducted through a partnership between the Department of Prevention and Community Health at George Washington…

  18. Organic Compounds in Potomac River Water Used for Public Supply near Washington, D.C., 2003-05

    Science.gov (United States)

    Brayton, Michael J.; Denver, Judith M.; Delzer, Gregory C.; Hamilton, Pixie A.

    2008-01-01

    Organic compounds studied in this U.S. Geological Survey (USGS) assessment generally are man-made, including, in part, pesticides, solvents, gasoline hydrocarbons, personal care and domestic-use products, and refrigerants and propellants. A total of 85 of 277 compounds were detected at least once among the 25 samples collected approximately monthly during 2003-05 at the intake of the Washington Aqueduct, one of several community water systems on the Potomac River upstream from Washington, D.C. The diversity of compounds detected indicate a variety of different sources and uses (including wastewater discharge, industrial, agricultural, domestic, and others) and different pathways (including treated wastewater outfalls located upstream, overland runoff, and ground-water discharge) to drinking-water supplies. Seven compounds were detected year-round in source-water intake samples, including selected herbicide compounds commonly used in the Potomac River Basin and in other agricultural areas across the United States. Two-thirds of the 26 compounds detected most commonly in source water (in at least 20 percent of the samples) also were detected most commonly in finished water (after treatment but prior to distribution). Concentrations for all detected compounds in source and finished water generally were less than 0.1 microgram per liter and always less than human-health benchmarks, which are available for about one-half of the detected compounds. On the basis of this screening-level assessment, adverse effects to human health are expected to be negligible (subject to limitations of available human-health benchmarks).

  19. 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).

  20. 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).

  1. 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....

  2. Seasonal variation of heavy metals in ambient air and precipitation at a single site in Washington, DC

    International Nuclear Information System (INIS)

    Melaku, Samuel; Morris, Vernon; Raghavan, Dharmaraj; Hosten, Charles

    2008-01-01

    Atmospheric samples of precipitation and ambient air were collected at a single site in Washington, DC, for 7 months (for ambient air samples) and 1 year (for wet deposition samples) and analyzed for arsenic, cadmium, chromium and lead. The ranges of heavy metal concentrations for 6-day wet deposition samples collected over the 1-year period were 0.20-1.3 μg/l, 0.060-5.1 μg/l, 0.062-4.6 μg/l and 0.11-3.2 μg/l for arsenic, cadmium, chromium and lead, respectively, with a precision better than 5% for more than 95% of the measurements. The ranges of heavy metal concentrations for the 6-day ambient air samples were 0.800-15.7 ng/m 3 , 1.50-30.0 ng/m 3 , 16.8-112 ng/m 3 , and 2.90-137 ng/m 3 for arsenic, cadmium, chromium and lead, respectively, with a precision better than 10%. The spread in the heavy metal concentration over the observation period suggests a high seasonal variability for heavy metal content in both ambient air and wet deposition samples. - High seasonal variability of heavy metals were observed in both ambient air and wet deposition samples

  3. 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.

  4. 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.

  5. 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.

  6. Health-hazard-evaluation report HETA 87-376-2018, US Department of Justice, United States Marshals Service, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    Reh, C.M.; Klein, M.K.

    1990-03-01

    In response to a request from the United States Marshals Service (SIC-9221) in Washington, D.C. for assistance in testing the effect of renovations to the ventilation system of their indoor firing range, lead (7439921) exposures were measured during handgun qualifying sessions. Each qualifying session of firing consisted of 60 rounds fired in 10 to 12 minutes. Personal breathing zone air samples were taken from three shooters and the range officer. Lead exposure concentrations measured were 2073, 1786, 172, and 142 micrograms of lead per cubic meter of air (microg/cu m). Eight hour time weighted average concentrations were calculated to be 194, 167, 101, and 13microg/cu m, respectively. The three shooters were therefore overexposed to lead. Bulk sampling of the sand from the bullet trap indicated it to be contaminated, containing 41% lead by weight. The authors concluded that a health hazard existed from exposure to lead. The authors recommended changes to improve the ventilation system. Following modification of the system, tests were again conducted and 11 of the 12 samples taken were below the limits of detection for the method used. The authors conclude that after modification, a hazard did not exist during qualifying sessions. The authors recommend specific measures to protect personnel from exposure to lead.

  7. Technical Working Group on Career and Technical Education Meeting. Meeting Summary (Washington, DC, September 22, 2017)

    Science.gov (United States)

    Ahn, Judie

    2017-01-01

    On September 22, 2017, the National Center for Special Education Research (NCSER) and the National Center for Education Research (NCER) at the Institute of Education Sciences (IES) convened a group of experts in policy, practice, and research related to Career and Technical Education (CTE). The goal of the meeting was to seek input from…

  8. The Society for Pediatric Radiology, 38th annual meeting, Washington, DC, USA, April 27-30, 1995. Gold medalists, honorary members, pioneer session, abstracts

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    The contribution reports the highlights of the 38th annual meeting of the Society for Pediatric Radiology in Washington, DC, from 27 - 30 April, 1995. The abstracts of the 96 papers presented at the sessions on all pediatric subject fields are reproduced, and the gold medalists of the Society of the year 1995 are introduced with a brief c.v. and a survey of their careers. (VHE) [de

  9. 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.

  10. Texts of joint USA-USSR statements following the summit meeting in Washington, D.C., 31 May - 3 June 1990

    International Nuclear Information System (INIS)

    1990-07-01

    The texts of joint USA-USSR statements following the summit meeting in Washington, D.C., 31 May - 3 June 1990 are reproduced. One is a joint statement on non-proliferation of nuclear weapons, missile and missile technology and chemical weapons, another one is a joint statement on the International Thermonuclear Experimental Reactor and the last one is a joint statement on Cooperation in Peaceful Uses of Atomic Energy

  11. 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

  12. Proceedings of Conference on Variable-Resolution Modeling, Washington, DC, 5-6 May 1992

    Science.gov (United States)

    1992-05-01

    lag (MM Kim (S󈨘-M 881 received the B.S.IM1. and M.S.F.n degrees from Ptisan National t.’ni- veisnv. Korea , and kwmpook National Univer- sity. Koiea...position in the Department Electronics. National Fisheries University of Pusan. Pusan. Korea , research interests include artificial intelligence...with the data or the modeler/analyst/ gamer is forced to make up interactions such as fire allocation, detailed acquisition predictions, small unit

  13. 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

  14. Research on key technology of planning and design for AC/DC hybrid distribution network

    Science.gov (United States)

    Shen, Yu; Wu, Guilian; Zheng, Huan; Deng, Junpeng; Shi, Pengjia

    2018-04-01

    With the increasing demand of DC generation and DC load, the development of DC technology, AC and DC distribution network integrating will become an important form of future distribution network. In this paper, the key technology of planning and design for AC/DC hybrid distribution network is proposed, including the selection of AC and DC voltage series, the design of typical grid structure and the comprehensive evaluation method of planning scheme. The research results provide some ideas and directions for the future development of AC/DC hybrid distribution network.

  15. 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 (spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration.

  16. 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 (spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration. PMID:26824489

  17. 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.

  18. 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.

  19. Testimony presented to the House Science and Technology Committee, 18 June 1981, Washington, DC

    International Nuclear Information System (INIS)

    Richmond, C.R.

    1981-10-01

    This report is the text of invited testimony given by the author before the House Science and Technology Committee. This Congressional hearing on Societal Risks of Energy Systems reflects the growing interest on the part of Congress, the public, the scientific community, and other groups on this extremely important topic of Risk Analysis. This presentation will contain information on the emergence of an interdisciplinary professional field of risk analysis, including the recently formed Society for Risk Analysis. I will also discuss in some detail various risk analysis programs now in progress at the Oak Ridge National Laboratory and other research institutions. Also included will be some general philosophy concerning risks from energy-producing systems and my perspective on the needs for further developments in the field of risk analysis

  20. Summer Computer Simulation Conference, Washington, DC, July 15-17, 1981, Proceedings

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Aspects of simulation technology are discussed, taking into account microcomputers in simulation, heuristic/adaptive systems, differential equations approaches, available simulation packages, selected operations research applications, and mathematical and statistical tools. Hybrid systems are discussed along with topics of chemical sciences. Subjects related to physical and engineering sciences are explored, giving attention to aeronautics and astronautics, physical processes, nuclear/electrical power technology, advanced computational methods and systems, avionics systems, dynamic systems analysis and control, and industrial systems. Environmental sciences are considered along with biomedical systems, managerial and social sciences, questions of simulation credibility and validation, and energy systems. A description is provided of simulation facilities, and topics related to system engineering and transportation are investigated

  1. The Impact of Recreational Marijuana Legislation in Washington, DC on Marijuana Use Cognitions.

    Science.gov (United States)

    Clarke, Paige; Dodge, Tonya; Stock, Michelle L

    2018-04-13

    There is little published research that tests the effect of recreational marijuana legislation on risk-related cognitions and how individuals respond immediately after legislative approval. The objective was to test whether learning about the passage of Initiative 71, a voter referendum that legalized recreational use of marijuana in the District of Columbia, would lead individuals to adopt more favorable marijuana cognitions than they had before the Initiative was passed. Undergraduate students (N = 402) completed two web-based questionnaires in 2014. The first questionnaire was completed prior to the referendum vote and the follow-up questionnaire was completed after voters approved Initiative 71. Attitudes, perceived norms, intentions, prototypes, and willingness were measured at time 1 and time 2. Study hypotheses were tested using repeated-measures analysis of covariance. Results showed that attitudes, intentions, perceived norms, and willingness to use marijuana were more favorable after Initiative 71 was passed. However, the increase in attitudes and willingness was moderated by past experience with marijuana whereby the increases were statistically significant only among those with the least experience. The increase in perceived norms was also moderated by past experience whereby increases were statistically significant among those who were moderate or heavy users. The passage of Initiative 71 had no effect on favorable prototypes. Conclusion/Importance: Legalization may have the unintended outcome of leading to more favorable intentions to use marijuana and might lead abstainers or experimental users to become more frequent users of marijuana via more positive attitudes and willingness towards marijuana use.

  2. A Cluster Analytic Examination of Acculturation and Health Status among Asian Americans in the Washington DC Metropolitan Area, United States

    Science.gov (United States)

    Lee, Sunmin; Chen, Lu; He, Xin; Miller, Matthew J.; Juon, Hee-Soon

    2013-01-01

    Previous studies reported mixed findings on the relationship between acculturation and health status among Asian Americans due to different types of acculturation measures used or different Asian subgroups involved in various studies. We aim to fill the gap by applying multiple measures of acculturation in a diverse sample of Asian subgroups. A cross sectional study was conducted among Chinese, Korean and Vietnamese Americans in Washington D.C. Metropolitan Area to examine the association between health status and acculturation using multiple measures including the Suinn-Lew Asian Self-Identity Acculturation (SL-ASIA) scale, clusters based on responses to SL-ASIA, language preference, length of stay, age at arrival in the United Sates and self-identity. Three clusters (Asian (31%); Bicultural (47%); and American (22%)) were created by using a two-step hierarchical method and Bayesian Information Criterion values. Across all the measures, more acculturated individuals were significantly more likely to report good health than those who were less acculturated after adjusting for covariates. Specifically, those in the American cluster were 3.8 times (95% Confidence Interval (CI): 2.2, 6.6) more likely and those in the Bicultural cluster were 1.7 times more likely (95% CI: 1.1, 2.4) to report good health as compared to those in the Asian cluster. When the conventional standardized SL-ASIA summary score (range: −1.4 to 1.4) was used, a one point increase was associated with 2.2 times greater odds of reporting good health (95% CI: 1.5, 3.2). However, the interpretation may be challenging due to uncertainty surrounding the meaning of a one point increase in SL-ASIA summary score. Among all the measures used, acculturation clusters better approximated the acculturation process and provided us with a more accurate test of the association in the population. Variables included in this measure were more relevant for our study sample and may have worked together to capture the

  3. Occurrence and Distribution of Organic Wastewater Compounds in Rock Creek Park, Washington, D.C., 2007-08

    Science.gov (United States)

    Phelan, Daniel J.; Miller, Cherie V.

    2010-01-01

    The U.S. Geological Survey, and the National Park Service Police Aviation Group, conducted a high-resolution, low-altitude aerial thermal infrared survey of the Washington, D.C. section of Rock Creek Basin within the Park boundaries to identify specific locations where warm water was discharging from seeps or pipes to the creek. Twenty-three stream sites in Rock Creek Park were selected based on the thermal infrared images. Sites were sampled during the summers of 2007 and 2008 for the analysis of organic wastewater compounds to verify potential sources of sewage and other anthropogenic wastewater. Two sets of stormwater samples were collected, on June 27-28 and September 6, 2008, at the Rock Creek at Joyce Road water-quality station using an automated sampler that began sampling when a specified stage threshold value was exceeded. Passive-sampler devices that accumulate organic chemicals over the duration of deployment were placed in July 2008 at the five locations that had the greatest number of detections of organic wastewater compounds from the June 2007 base-flow sampling. During the 2007 base-flow synoptic sampling, there were ubiquitous low-level detections of dissolved organic wastewater indicator compounds such as DEET, caffeine, HHCB, and organophosphate flame retardants at more than half of the 23 sites sampled in Rock Creek Park. Concentrations of DEET and caffeine in the tributaries to Rock Creek were variable, but in the main stem of Rock Creek, the concentrations were constant throughout the length of the creek, which likely reflects a distributed source. Organophosphate flame retardants in the main stem of Rock Creek were detected at estimated concentrations of 0.2 micrograms per liter or less, and generally did not increase with distance downstream. Overall, concentrations of most wastewater indicators in whole-water samples in the Park were similar to the concentrations found at the upstream sampling station at the Maryland/District of Columbia

  4. DC-DC power converter research for Orbiter/Station power exchange

    Science.gov (United States)

    Ehsani, M.

    1993-01-01

    This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.

  5. Research of digital controlled DC/DC converter based on STC12C5410AD

    Science.gov (United States)

    Chen, Dan-Jiang; Jin, Xin; Xiao, Zhi-Hong

    2010-02-01

    In order to study application of digital control technology on DC/DC converter, principle of increment mode PID control algorithm was analyzed in the paper. Then, a SCM named STC12C5410AD was introduced with its internal resources and characteristics. The PID control algorithm can be implemented easily based on it. The output of PID control was used to change the value of a variable that is 255 times than duty cycle, and this reduced the error of calculation. The valid of the presented algorithm was verified by an experiment for a BUCK DC/DC converter. The experimental results indicated that output voltage of the BUCK converter is stable with low ripple.

  6. Brushless DC motor speed control strategy of simulation research

    Directory of Open Access Journals (Sweden)

    Xiang Wen

    2017-01-01

    Full Text Available In view of the brushless DC motor speed regulation problem, an ideal control strategy is designed. Through the model and analysis of Brushless DC motor, the mathematical model of the brushless DC motor is obtained. By comparing three control strategies of PID control strategy, fuzzy control strategy and fuzzy PID control strategy, PID controller, fuzzy controller and fuzzy PID controller are designed respectively for simulation test. The simulation results show that the fuzzy PID controller has good control effect.

  7. Do Not Forget About Public Transportation: Analysis of the Association of Active Transportation to School Among Washington, DC Area Children With Parental Perceived Built Environment Measures.

    Science.gov (United States)

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

    2018-03-23

    Although the active transportation (AT) indicator received an F grade on the 2016 US Report Card on Physical Activity for Children and Youth, this AT assessment excluded public transportation. An objective of the Built Environment and Active Play Study was to assess youth AT, including public transportation, among Washington, DC area children in relation to parental perceptions of neighborhood built environment (BE) variables. Questionnaires were mailed to 2000 parents of children aged 7-12 years. AT to school (ATS) was assessed with the question: "In an average school week, how many days does your child use each of the following ways to get to and from school? (a) Walk; (b) Bike; (c) Car; (d) Bus or Metro." Parental perceived BE data were obtained through questionnaire items, and logistic regression was conducted to determine if BE variables were associated with youth ATS. The sample included 144 children (50% female; average age 9.7 years; 56.3% white; 23.7% African American; 10.4% Asian American). Over 30% used ATS-public transportation 5 days per week, and nearly 13% used ATS-walking daily. Parental perceived BE variables significantly predicted youth ATS-walking and ATS-public transportation. ATS-public transportation is common among Washington, DC area youth, and parental perceptions of BE can significantly predict ATS.

  8. 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.

  9. Spatial and temporal structure of typhoid outbreaks in Washington, D.C., 1906–1909: evaluating local clustering with the Gi* statistic

    Directory of Open Access Journals (Sweden)

    Curtis Andrew

    2006-03-01

    Full Text Available Abstract Background To better understand the distribution of typhoid outbreaks in Washington, D.C., the U.S. Public Health Service (PHS conducted four investigations of typhoid fever. These studies included maps of cases reported between 1 May – 31 October 1906 – 1909. These data were entered into a GIS database and analyzed using Ripley's K-function followed by the Gi* statistic in yearly intervals to evaluate spatial clustering, the scale of clustering, and the temporal stability of these clusters. Results The Ripley's K-function indicated no global spatial autocorrelation. The Gi* statistic indicated clustering of typhoid at multiple scales across the four year time period, refuting the conclusions drawn in all four PHS reports concerning the distribution of cases. While the PHS reports suggested an even distribution of the disease, this study quantified both areas of localized disease clustering, as well as mobile larger regions of clustering. Thus, indicating both highly localized and periodic generalized sources of infection within the city. Conclusion The methodology applied in this study was useful for evaluating the spatial distribution and annual-level temporal patterns of typhoid outbreaks in Washington, D.C. from 1906 to 1909. While advanced spatial analyses of historical data sets must be interpreted with caution, this study does suggest that there is utility in these types of analyses and that they provide new insights into the urban patterns of typhoid outbreaks during the early part of the twentieth century.

  10. 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.

  11. Proceedings of the 1993 Particle Accelerator Conference Held in Washington, DC on May 17-20, 1993. Volume 2

    Science.gov (United States)

    1993-05-20

    Shapiro, S. Bethke, 0. Chamberlain, R. Fuzesy, M. Kowitt, D. Pripstein, B. Schumm, H. Steiner , M. Zolotorev, LBL; P. Rowson, Columbia; D. Blockus, H...Conference Proceedings, March 1989. 2. Rudolf P. Sevems, and Gordon E. Bloom, "Modern DC- to-DC Switchmode Power Converter Circuits," Van Nostrand...R. E. 2471 Steiner , H. 2172 Sytnikov, V. 2769 Thevenot, M. 670, 697 Steinhauer. L. C. 2564, 2581, Thiagarajan, V. 3372 2614 Thieberger, P. 3178

  12. Annual Research Progress Report (U.S. Army Institute of Dental Research, Washington, DC)

    Science.gov (United States)

    1978-10-01

    to the oral cavity , with its abundance and variety of streptococci, has recently been implicated as playing a larger role than previously appreciated...the dressings of oral wounds. Impending studies will more closely identify the microbiota involved and the importance to healing in the oral ...to the oral cavity as was seen in a similar study in which stainless steel wires were used to achieve fixation. 5) The staples apply continuous

  13. Comparing MODIS-Terra and GOES surface albedo for New York City NY, Baltimore MD and Washington DC for 2005

    Science.gov (United States)

    Mubenga, K.; Hoff, R.; McCann, K.; Chu, A.; Prados, A.

    2006-05-01

    The NOAA GOES Aerosol and Smoke Product (GASP) is a product displaying the Aerosol Optical Depth (AOD) over the United States. The GASP retrieval involves discriminating the upwelling radiance from the atmosphere from that of the variable underlying surface. Unlike other sensors with more visible and near- infrared spectral channels such as MODIS, the sensors on GOES 8 through 12 only have one visible and a several far infrared channels. The GASP algorithm uses the detection of the second-darkest pixel from the visible channel over a 28-day period as the reference from which a radiance look-up table gives the corresponding AOD. GASP is reliable in capturing the AOD during large events. As an example, GASP was able to precisely show the Alaska and British Columbia smoke plume advecting from Alaska to the northeastern U.S. during the summer of 2004. Knapp et al. (2005) has shown that the AOD retrieval for GOES- 8 is within +/-0.13 of AERONET ground data with a coefficient of correlation of 0.72. Prados (this meeting) will update that study. However, GASP may not be as reliable when it comes to observing smaller AOD events in the northeast where the surface brightness is relatively high. The presence of large cities, such as New York, increases the surface albedo and produces a bright background against which it may be difficult to deduce the AOD. The Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on the Earth Observing System Terra and Aqua platforms provides an independent measurement of the surface albedo at a resolution greater than available on GOES. In this research, the MODIS and GOES surface albedo product for New York, Washington and Baltimore are compared in order to see how we can improve the AOD retrieval in urban areas for air quality applications. Ref: K. Knapp et al. 2005. Toward aerosol optical depth retrievals over land from GOES visible radiances: determining surface reflectance. Int.Journal of Remote Sensing 26, 4097-4116

  14. Job Satisfaction among Information Technology Professionals in the Washington DC Area: An Analysis Based on the Minnesota Satisfaction Questionnaire

    Science.gov (United States)

    Diala, Ify S.

    2010-01-01

    Information technology (IT) has in the recent times dominated all aspect of the business world, and, for this reason, today's business environment is more challenging and more dynamic than in previous years. Therefore, this study focused on examining job satisfaction of Information Technology professionals in the D.C. area, paying particular…

  15. 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

  16. 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

  17. 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)

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

    2015-01-01

    Background 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. Objective 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. Methods 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. Results 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. Conclusions 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

  18. Epithermal neutron beam for BNCT research at the Washington State University TRIGA research reactor

    International Nuclear Information System (INIS)

    Nigg, D.W.; Venhuizen, J.R.; Wheeler, F.J.; Wemple, C.A.; Tripard, G.E.; Gavin, P.R.

    2000-01-01

    A new epithermal-neutron beam facility for BNCT (Boron Neutron Capture Therapy) research and boronated agent screening in animal models is in the final stages of construction at Washington State University (WSU). A key distinguishing feature of the design is the incorporation of a new, high-efficiency, neutron moderating and filtering material, Fluental, developed by the Technical Research Centre of Finland. An additional key feature is the provision for adjustable filter-moderator thickness to systematically explore the radiobiological consequences of increasing the fast-neutron contamination above the nominal value associated with the baseline system. (author)

  19. Proceedings of the 1993 Particle Accelerator Conference Held in Washington, DC on May 17-20, 1993. Volume 5

    Science.gov (United States)

    1994-05-18

    stability. o)i-_ =o)- +I +aOc. Summarizing above relations, the net transfer of power per electron with kinetic energy W is written RI ado ;k of d method•. as... Porno . equations (3)XS) in cylindrical[V~ -lA!-]+ (Ip+2q)A coordinates for a general, Le. not necessarily azxiymanet-2a dC ric, beam. It is valid for

  20. Research on Two-channel Interleaved Two-stage Paralleled Buck DC-DC Converter for Plasma Cutting Power Supply

    DEFF Research Database (Denmark)

    Yang, Xi-jun; Qu, Hao; Yao, Chen

    2014-01-01

    As for high power plasma power supply, due to high efficiency and flexibility, multi-channel interleaved multi-stage paralleled Buck DC-DC Converter becomes the first choice. In the paper, two-channel interleaved two- stage paralleled Buck DC-DC Converter powered by three-phase AC power supply...

  1. A Research Partnership: Experience in Washington County PA

    Science.gov (United States)

    Vukotich, Charles J., Jr.; Lani, Grace M.

    2018-01-01

    Schools are valuable venues for research institutions. Research can also be beneficial to public schools. School administrators should be proactive in identifying research topics and establishing standards and expectations for the university researchers. This article describes the partnership between a university researcher and a K-12 director of…

  2. Federal research natural areas in Oregon and Washington: a guidebook for scientists and educators.

    Science.gov (United States)

    Jerry F. Franklin; Fredrick C. Hall; C. T. Dyrness; Chris. Maser

    1972-01-01

    A guide to the use of natural scientific preserves, Research Natural Areas, on Federal lands in Oregon and Washington. Detailed descriptions of physical and biological features, maps and photographs are provided for each of the 45 tracts presently reserved. Indices to Research Natural Areas by vegetation type and plant and mammalian species are included.

  3. Research on DC Micro-grid system of photovoltaic power generation

    Science.gov (United States)

    Zheng, Yiming; Wang, Xiaohui

    2018-01-01

    The use of energy has become a topic of concern, the demand of people for power grows in number or quantity with the development of economy. It is necessary to consider using new forms of power supply-microgrid system for distributed power supply. The power supply mode can not only effectively solve the problem of excessive line loss in the large power grid, but also can increase the reliability of the power supply, and is economical and environmental friendly. With the increasing of DC loads, in order to improve the utilization efficiency, the DC microgrid power supply problems are begin to be researched and integrated with the renewable energy sources. This paper researched the development of microgrid, compared AC microgrid with DC microgrid, summarized the distribution of DC bus voltage level, the DC microgrid network form, the control mode and the main power electronics elements of DC microgrid of photovoltaic power generation system. Today, the DC microgrid system is still in the development stage without uniform voltage level standard, however, it will come into service in the future.

  4. Processes Controlling CH2O Over the Baltimore/Washington DC Metropolitan Region: A Box Model Analysis Using Data from DISCOVER-AQ

    Science.gov (United States)

    Olson, J. R.; Crawford, J. H.; Fried, A.; Wisthaler, A.; Weinheimer, A. J.; Barrick, J. D.; Diskin, G. S.; Duncan, B. N.; Mikoviny, T.

    2012-12-01

    The first deployment for NASA's Earth Venture campaign DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) took place over the Baltimore/Washington DC region during July of 2011. Observations of CH2O in the lowest kilometer (pressure-altitude) indicate that median concentrations can vary day to day by as much as 5 ppbv. Further, variability within a single day can correlate with a number of species, including H2O, temperature, isoprene, and/or CO. The NASA Langley photochemical box model is used to examine the dominant budget terms for CH2O during DISCOVER-AQ and to diagnose the drivers of the CH2O variability. Modeling results show that the source of CH2O is largely dominated by isoprene. However, the variability of CH2O within single flight days is rarely directly correlated to isoprene. Rather, most often, CH2O variability is correlated to the oxidative capacity of the atmosphere, defined by OH and driven by OH precursors such as H2O, O3 photolysis rates, and NO. Sensitivity model runs where isoprene is held constant to daily medians show excellent ability to predict both the overall CH2O concentration (dominated by isoprene) and the variability of CH2O throughout a day (driven by variations in oxidative capacity).

  5. The Influence of Family Dog Ownership and Parental Perceived Built Environment Measures on Children's Physical Activity within the Washington, DC Area.

    Science.gov (United States)

    Roberts, Jennifer D; Rodkey, Lindsey; Grisham, Cortney; Ray, Rashawn

    2017-11-16

    Sedentary behavior and physical inactivity are significant contributors to youth obesity in the United States. Neighborhood dog walking is an outlet for physical activity (PA). Therefore, understanding the relationship between built environment, dog ownership, and youth PA is essential. This study examined the influence of dog ownership and parental built environment perceptions on children's PA in the Washington, D.C. area. In 2014, questionnaires were mailed to 2000 parents to assess family dog ownership; children's outdoor dog walking or playing; and parental perceived built environment measures. Chi-square analyses examined differences in parental perceived built environment measures between children with and without family dogs. The sample included 144 children (50% female; average-age 9.7 years; 56.3% White; 23.7% African-American; 10.4% Asian-American; 29.9% owned dog). Only 13% and 5.6% of the children walked or played outdoors with the dog daily, respectively. A significantly greater proportion ( p -value supports children's outdoor PA through dog walking and playing.

  6. Improving Health, Social Welfare, and Human Development Through Women's Empowerment in Developing Countries: The 2016 Girl Up Leadership Summit, Washington, DC, USA.

    Science.gov (United States)

    Mendoza, Janel

    2016-01-01

    The United Nations Foundation's Girl Up campaign, an initiative dedicated to promoting the health, education, and leadership of adolescent girls in developing communities around the world, hosted its annual Girl Up Leadership Summit in Washington, DC from July 11-13, 2016. The summit welcomed more than 275 girl empowerment and women empowerment proponents to take part in leadership training, listen to and learn from influential figures like United Nations Deputy High Commissioner for Human Rights Kate Gilmore and Treasurer of the United States Rosie Rios, as well as engage in an official lobby day in the nation's capital. Topics discussed at the summit ranged from the issue of child marriage and sexual and reproductive health rights to intersectional feminism and the importance of the next generation of global girl advocates. The purpose and, later on, achievement of the conference was the development of such leaders and Girl Up representatives. Summit attendee and Girl Up Campus Leader Janel Mendoza shares her experience as a longstanding Girl Up supporter and reflects on the preeminent conversations held during and following the summit.

  7. Improving Health, Social Welfare, and Human Development Through Women’s Empowerment in Developing Countries: The 2016 Girl Up Leadership Summit, Washington, DC, USA

    Science.gov (United States)

    Mendoza, Janel

    2016-01-01

    The United Nations Foundation’s Girl Up campaign, an initiative dedicated to promoting the health, education, and leadership of adolescent girls in developing communities around the world, hosted its annual Girl Up Leadership Summit in Washington, DC from July 11-13, 2016. The summit welcomed more than 275 girl empowerment and women empowerment proponents to take part in leadership training, listen to and learn from influential figures like United Nations Deputy High Commissioner for Human Rights Kate Gilmore and Treasurer of the United States Rosie Rios, as well as engage in an official lobby day in the nation’s capital. Topics discussed at the summit ranged from the issue of child marriage and sexual and reproductive health rights to intersectional feminism and the importance of the next generation of global girl advocates. The purpose and, later on, achievement of the conference was the development of such leaders and Girl Up representatives. Summit attendee and Girl Up Campus Leader Janel Mendoza shares her experience as a longstanding Girl Up supporter and reflects on the preeminent conversations held during and following the summit. PMID:28058195

  8. Sleep Needs, Patterns, and Difficulties of Adolescents: Summary of a Workshop. Forum on Adolescence (Washington, DC, September 22, 1999).

    Science.gov (United States)

    Graham, Mary G., Ed.

    This report summarizes the presentations and discussion at a workshop on adolescent sleep. The workshop was organized by the Board on Children, Youth, and Families and the Forum on Adolescence of the National Research Council and Institute of Medicine. The workshop brought together policy makers, researchers, and practitioners to examine research…

  9. DOE role in nuclear policies and programs: official transcript of public briefing. Addendum December 13, 1977, Washington, D.C

    International Nuclear Information System (INIS)

    1978-02-01

    A total of 24 questions were read into the official record at the public briefing on nuclear policies and programs. The answers published were researched and written by personnel of DOE's Office of Energy Research, Office of Energy Technology, and the Secretary's Office. A few questions were sent to the Nuclear Regulatory Commission for review and for preparation of answers

  10. Proceedings of the Acquisition Research Symposium Held in Washington, DC, October 1989

    Science.gov (United States)

    1989-10-01

    PRICE, SLIM COCOMO, JS-3, SPQR -20, Softcost-R, etc) Cost questionnaire/ interview process Cost i methodology ueslionnaire/inlerview proc«»s...investigate the applicability of several cost models for trusted code cost and schedule estimation. The models examined were: SPQR /20...unsuccessful in calibrating either SPQR /20 or Softcost-R to a trusted code development environment. SPQR /20’s Internal calibration feature

  11. Scientific Grand Challenges: Crosscutting Technologies for Computing at the Exascale - February 2-4, 2010, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    Khaleel, Mohammad A.

    2011-02-06

    The goal of the "Scientific Grand Challenges - Crosscutting Technologies for Computing at the Exascale" workshop in February 2010, jointly sponsored by the U.S. Department of Energy’s Office of Advanced Scientific Computing Research and the National Nuclear Security Administration, was to identify the elements of a research and development agenda that will address these challenges and create a comprehensive exascale computing environment. This exascale computing environment will enable the science applications identified in the eight previously held Scientific Grand Challenges Workshop Series.

  12. Human Factors in Automated and Robotic Space Systems: Proceedings of a Symposium Held in Washington, DC in 1987

    Science.gov (United States)

    1987-01-01

    profession in the quality of its judgments, there is not that much of a research base on which to base a defense ( Feyerabend , 1975; Morgan et al., 1981...Feather, N. T. 1982 Expectancy, Incentive, and Action. Hillsdale, NJ. Feyerabend , P. 1975 Against Method. London: Verso. Fischhoff, B. 1975

  13. Bottom Line Conference Held on May 13, 1982 at Fort Lesley J. McNair, Washington, DC.

    Science.gov (United States)

    1982-01-01

    WITH THE P. PRIVATE SECTOR . WE CAN ANTICIPATE ACQUIRING THE QUALITY MATERIEL * THAT IS THE HALLMARK OF THE BEST ARMY IN THE WORLD. (SLIDE 10 OFF) 8 140...TERMS OF IMPROVED MORALE. THIS ADDS A NEW DIMENSION TO THE EMPLOYE’ S WORKLIFE --- CHALLENGING HIM TO COMMIT HIS MIND TO HIS JOB; AS WELL AS HIS HANDS...THE DOLLARS THAT WE NEED FOR RAM AND PRODUCT ASSURANCE. WE MUST RELY * ON INDUSTRY TO HELP FILL THE GAPS THROUGH PRIVATE RESEARCH AND DEVELOPMENT

  14. 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.

  15. Turbulent Flow Simulation at the Exascale: Opportunities and Challenges Workshop: August 4-5, 2015, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    Sprague, Michael A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Boldyrev, Stanislav [Univ. of Wisconsin, Madison, WI (United States); Fischer, Paul [Argonne National Lab. (ANL), Argonne, IL (United States); Univ. of Illinois, Urbana-Champaign, IL (United States); Grout, Ray [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gustafson, Jr., William I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moser, Robert [Univ. of Texas, Austin, TX (United States)

    2017-01-01

    This report details the impact exascale will bring to turbulent-flow simulations in applied science and technology. The need for accurate simulation of turbulent flows is evident across the DOE applied-science and engineering portfolios, including combustion, plasma physics, nuclear-reactor physics, wind energy, and atmospheric science. The workshop brought together experts in turbulent-flow simulation, computational mathematics, and high-performance computing. Building upon previous ASCR workshops on exascale computing, participants defined a research agenda and path forward that will enable scientists and engineers to continually leverage, engage, and direct advances in computational systems on the path to exascale computing.

  16. Siting Background Towers to Characterize Incoming Air for Urban Greenhouse Gas Estimation: A Case Study in the Washington, DC/Baltimore Area

    Science.gov (United States)

    Mueller, K.; Yadav, V.; Lopez-Coto, I.; Karion, A.; Gourdji, S.; Martin, C.; Whetstone, J.

    2018-03-01

    There is increased interest in understanding urban greenhouse gas (GHG) emissions. To accurately estimate city emissions, the influence of extraurban fluxes must first be removed from urban greenhouse gas (GHG) observations. This is especially true for regions, such as the U.S. Northeastern Corridor-Baltimore/Washington, DC (NEC-B/W), downwind of large fluxes. To help site background towers for the NEC-B/W, we use a coupled Bayesian Information Criteria and geostatistical regression approach to help site four background locations that best explain CO2 variability due to extraurban fluxes modeled at 12 urban towers. The synthetic experiment uses an atmospheric transport and dispersion model coupled with two different flux inventories to create modeled observations and evaluate 15 candidate towers located along the urban domain for February and July 2013. The analysis shows that the average ratios of extraurban inflow to total modeled enhancements at urban towers are 21% to 36% in February and 31% to 43% in July. In July, the incoming air dominates the total variability of synthetic enhancements at the urban towers (R2 = 0.58). Modeled observations from the selected background towers generally capture the variability in the synthetic CO2 enhancements at urban towers (R2 = 0.75, root-mean-square error (RMSE) = 3.64 ppm; R2 = 0.43, RMSE = 4.96 ppm for February and July). However, errors associated with representing background air can be up to 10 ppm for any given observation even with an optimal background tower configuration. More sophisticated methods may be necessary to represent background air to accurately estimate urban GHG emissions.

  17. 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/

  18. A novel DC Magnetron sputtering facility for space research and synchrotron radiation optics

    DEFF Research Database (Denmark)

    Hussain, A.M.; Christensen, Finn Erland; Pareschi, G.

    1998-01-01

    A new DC magnetron sputtering facility has been build up at the Danish Space Research Institute (DSRI), specially designed to enable uniform coatings of large area curved optics, such as Wolter-I mirror optics used in space telescopes and curved optics used in synchrotron radiation facilities...

  19. Research on resistance characteristics of YBCO tape under short-time DC large current impact

    Science.gov (United States)

    Zhang, Zhifeng; Yang, Jiabin; Qiu, Qingquan; Zhang, Guomin; Lin, Liangzhen

    2017-06-01

    Research of the resistance characteristics of YBCO tape under short-time DC large current impact is the foundation of the developing DC superconducting fault current limiter (SFCL) for voltage source converter-based high voltage direct current system (VSC-HVDC), which is one of the valid approaches to solve the problems of renewable energy integration. SFCL can limit DC short-circuit and enhance the interrupting capabilities of DC circuit breakers. In this paper, under short-time DC large current impacts, the resistance features of naked tape of YBCO tape are studied to find the resistance - temperature change rule and the maximum impact current. The influence of insulation for the resistance - temperature characteristics of YBCO tape is studied by comparison tests with naked tape and insulating tape in 77 K. The influence of operating temperature on the tape is also studied under subcooled liquid nitrogen condition. For the current impact security of YBCO tape, the critical current degradation and top temperature are analyzed and worked as judgment standards. The testing results is helpful for in developing SFCL in VSC-HVDC.

  20. Research on Digital Output Verification Technology of Electronic DC Current Transformer

    Science.gov (United States)

    Chen, Yuanjie; Wang, Bin; Hu, Haoliang; Xiong, Qianzhu; Yang, Chunyan

    2017-05-01

    Aiming at the error of calibration system when conducting field calibration by electronic DC current transformer’s digital calibration system, an electronic DC current transformer’s digital calibration system based on protocol conversion is proposed and researched. Data frames outputted from merging unit are collected and converted by the system, the digital synchronization is realized by using the synchronous clock device to trigger the second pulse, and it is verified by the virtual instrument design software. The field calibration is conducted to some converter station digital dc current transformer under the rated current of 500A by using the calibration system. By calibrating and analyzing errors, the error is less than 0.075% when tested current is more than 40% of the rated current. According the standard in literature[1], performance of the calibration system is perfect, measured results perfectly meet the requirements of design, and the calibration system has great practical application value.

  1. Electric and magnetic field reduction and research: A report to the Washington State Legislature

    International Nuclear Information System (INIS)

    Geissinger, L.G.; Waller, P.; Chartier, V.L.; Olsen, R.G.

    1993-01-01

    Increasingly, citizens of Washington State are expressing their concerns about possible adverse health effects of electric and magnetic fields (EMF) from electric utility power systems. A number of legislative proposals over the past several years have prompted governmental officials to evaluate available options for reducing electric and magnetic field strengths surrounding these systems (with a concentration on magnetic fields) or otherwise manage public exposure to power lines by increasing land use controls and setbacks for new development. Unsuccessful proposals brought before the Washington Legislature include 2 mG magnetic field limits for new transmission lines at the right-of-way edge; a temporary moratorium on transmission construction; requirements for providing public information on EMF; and expansion of the role of state governmental agencies in transmission siting and design. A successful Whatcom County initiative limits the voltage of new transmission to 115 kV in all but industrial land use zones, an action likely to have an unintended outcome of increasing magnetic fields in some areas. It is clear that better communication is needed about possible options for EMF management, costs and consequences, despite the fact scientific evidence on the existence of human health effects is inconclusive. This paper describes the work that Washington State undertook in 1990-92 in response to Engrossed Substitute Senate Bill 6771 establishing the Electric Transmission Research Needs Task Force. The Task Force was directed to report to the Legislature on possible exposure reduction methods; recommending engineering research that could lead to more effective approaches in the future

  2. 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.

  3. Virginia Tech launches Energy Efficiency Partnership with Hannon Armstrong and Pepco Energy Services aimed at greening greater Washington, D.C.

    OpenAIRE

    Micale, Barbara L.

    2007-01-01

    Virginia Tech announced Monday the "Energy Efficiency Partnership of Greater Washington," a landmark initiative to tackle the problem of global warming by retrofitting existing buildings with energy efficiency products designed to decrease energy use and significantly cut carbon emissions.

  4. Research on design feasibility of high-power light-weight dc-to-dc converters for space power applications

    Science.gov (United States)

    Wilson, T. G.

    1981-01-01

    Utilizing knowledge gained from past experience with experimental current-or-voltage step-up dc-to-dc converter power stages operating at output powers up to and in excess of 2 kW, a new experimental current-or-voltage step-up power stage using paralleled bipolar junction transistors (BJTs) as the controlled power switch, was constructed during the current reporting period. The major motivation behind the construction of this new experimental power stage was to improve the circuit layout so as to reduce the effects of stray circuit parasitic inductances resulting from excess circuit lead lengths and circuit loops, and to take advantage of the layout improvements which could be made when some recently-available power components, particularly power diodes and polypropylene filter capacitors, were incorporated into the design.

  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. 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

    Science.gov (United States)

    Saksvig, Brit Irene; Brachman, Micah L.; Durand, Casey P.

    2018-01-01

    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.

  7. 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.

  8. PREFACE PASREG: The 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials (Washington DC, 29-31 July 2010) PASREG: The 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials (Washington DC, 29-31 July 2010)

    Science.gov (United States)

    Freyhardt, Herbert; Cardwell, David; Strasik, Mike

    2010-12-01

    Large grain, (RE)BCO bulk superconductors fabricated by top seeded melt growth (TSMG) are able to generate large magnetic fields compared to conventional, iron-based permanent magnets. Following 20 years of development, these materials are now beginning to realize their considerable potential for a variety of engineering applications such as magnetic separators, flywheel energy storage and magnetic bearings. MgB2 has also continued to emerge as a potentially important bulk superconducting material for engineering applications below 20 K due to its lack of granularity and the ease with which complex shapes of this material can be fabricated. This issue of Superconductor Science and Technology contains a selection of papers presented at the 7th International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials, including MgB2, held 29th-31sy July 2010 at the Omni Shoreham Hotel, Washington DC, USA, to report progress made in this field in the previous three year period. The workshop followed those held previously in Cambridge, UK (1997), Morioka, Japan (1999), Seattle, USA (2001), Jena, Germany (2003), Tokyo, Japan (2005) and again in Cambridge, UK (2007). The scope of the seventh PASREG workshop was extended to include processing and characterization aspects of the broader spectrum of bulk high temperature superconducting (HTS) materials, including melt-cast Bi-HTS and bulk MgB2, recent developments in the field and innovative applications of bulk HTS. A total of 38 papers were presented at this workshop, of which 30 were presented in oral form and 8 were presented as posters. The organizers wish to acknowledge the efforts of Sue Butler of the University of Houston for her local organization of the workshop. The eighth PASREG workshop will be held in Taiwan in the summer of 2012.

  9. Directions in engineering research: an assessment of opportunities and needs

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Engineering and Technical Systems; Division on Engineering and Physical Sciences; National Research Council

    1987-01-01

    ... Commission on Engineering and Technical Systems National Research Council Washington, D.C. NATIONAL ACADEMY PRESS Washington, D.C. 1987 i 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 recomposed styles, v...

  10. A One-Size-Fits-All HIV Prevention and Education Approach?: Interpreting Divergent HIV Risk Perceptions Between African American and East African Immigrant Women in Washington, DC Using the Proximate-Determinants Conceptual Framework.

    Science.gov (United States)

    De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia

    2016-02-01

    To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women's perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the United States. Forty in-depth, semistructured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semistructured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Adopting Boerma and Weir's Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. Although African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Study findings suggest that addressing HIV prevention and education among black women in DC will require distinct and targeted strategies that are culturally and community-centered to resonate with these different audiences.

  11. A one-size-fits-all HIV prevention and education approach?: Analyzing and interpreting divergent HIV risk perceptions between African American and East African immigrant women in Washington, DC

    Science.gov (United States)

    De Jesus, Maria; Taylor, Juanita; Maine, Cathleen; Nalls, Patricia

    2015-01-01

    Background To date, there are very few comparative US studies and none in DC that distinguish between US-born and foreign-born Black women to examine and compare their perceptions of HIV risk. This qualitative study, therefore, analyzes African American and East African women’s perceptions of HIV risk in the Washington DC Metropolitan area, which has the highest AIDS rate in the US. Methods Forty in-depth, semi-structured interviews and 10 cognitive interviews were conducted among a sample of 25 African American women and 25 East African born women between October 2012 and March 2013 to examine perceptions regarding HIV risk. The in-depth semi-structured interviews were preceded by the cognitive interviews and accompanying survey. Study protocol was reviewed and approved by the American University Institutional Review Board. Results Adopting Boerma and Weir’s Proximate Determinants conceptual framework to interpret the data, the results of the study demonstrate that African American and East African immigrant women have divergent perceptions of HIV risk. While African American women ascribe HIV risk to individual-level behaviors and choices such as unprotected sex, East African women attribute HIV risk to conditions of poverty and survival. Conclusions Study findings suggest that addressing HIV prevention and education among Black women in DC will require distinct and targeted strategies that are culturally and community-centered in order to resonate with these different audiences. PMID:26766523

  12. Acute stroke imaging research roadmap

    NARCIS (Netherlands)

    Wintermark, Max; Albers, Gregory W.; Alexandrov, Andrei V.; Alger, Jeffry R.; Bammer, Roland; Baron, Jean-Claude; Davis, Stephen; Demaerschalk, Bart M.; Derdeyn, Colin P.; Donnan, Geoffrey A.; Eastwood, James D.; Fiebach, Jochen B.; Fisher, Marc; Furie, Karen L.; Goldmakher, Gregory V.; Hacke, Werner; Kidwell, Chelsea S.; Kloska, Stephan P.; Koehrmann, Martin; Koroshetz, Walter; Lee, Ting-Yim; Lees, Kennedy R.; Lev, Michael H.; Liebeskind, David S.; Ostergaard, Leif; Powers, William J.; Provenzale, James; Schellinger, Peter; Silbergleit, Robert; Sorensen, Alma Gregory; Wardlaw, Joanna; Warach, Steven

    The recent "Advanced Neuroimaging for Acute Stroke Treatment" meeting on September 7 and 8, 2007 in Washington DC, brought together stroke neurologists, neuroradiologists, emergency physicians, neuroimaging research scientists, members of the National Institute of Neurological Disorders and Stroke

  13. Proceedings of the Annual Military Librarians’ Workshop (31st): Information Management and Intelligence Held in Washington, D.C. on 20-23 October 1987

    Science.gov (United States)

    1987-10-23

    marks an important step forward in the transformation of the worn out late Roman Empire into the new and vigorous organization of the Medieval ...presumably read and used. The fact that officers in the Byzantine Army had to be able to read and write by itself sets it apart from other medieval ... Literatura Washington: Central Intelligence Agency, 1955. 13. GRABO, Cynthia M. W~arn g•J.~jttliancxA McLean, Virginia: Association of Former Intelligence

  14. Census Cities experiment in urban change detection. [mapping of land use changes in San Francisco, Washington D.C., Phoenix, Tucson, Boston, New Haven, Cedar Rapids, and Pontiac

    Science.gov (United States)

    Wray, J. R. (Principal Investigator); Milazzo, V. A.

    1974-01-01

    The author has identified the following significant results. Mapping of 1970 and 1972 land use from high-flight photography has been completed for all test sites: San Francisco, Washington, Phoenix, Tucson, Boston, New Haven, Cedar Rapids, and Pontiac. Area analysis of 1970 and 1972 land use has been completed for each of the mandatory urban areas. All 44 sections of the 1970 land use maps of the San Francisco test site have been officially released through USGS Open File at 1:62,500. Five thousand copies of the Washington one-sheet color 1970 land use map, census tract map, and point line identification map are being printed by USGS Publication Division. ERTS-1 imagery for each of the eight test sites is being received and analyzed. Color infrared photo enlargements at 1:100,000 of ERTS-1 MSS images of Phoenix taken on October 16, 1972 and May 2, 1973 are being analyzed to determine to what level land use and land use changes can be identified and to what extent the ERTS-1 imagery can be used in updating the 1970 aircraft photo-derived land use data base. Work is proceeding on the analysis of ERTS-1 imagery by computer manipulation of ERTS-1 MSS data in digital format. ERTS-1 CCT maps at 1:24,000 are being analyzed for two dates over Washington and Phoenix. Anniversary tape sets have been received at Purdue LARS for some additional urban test sites.

  15. 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

  16. The Impact of NSF-funded Physics Education Research at the University of Washington

    Science.gov (United States)

    Heron, Paula

    2015-03-01

    It is now well known that many students who complete introductory physics courses are unable to apply fundamental concepts in situations that involve qualitative reasoning. Systematic investigations have helped researchers understand why so many students fail to develop robust and coherent conceptual frameworks, and have led to the development of new teaching practices and materials that are far more effective than conventional ones. The Physics Education Group at the University of Washington has played a leading role in raising awareness of the need to improve instruction, and in supporting physics faculty in their efforts to do so. With support from the National Science Foundation, the group has helped build a research base that instructors can draw on, and has produced practical, flexible instructional materials that promote deeper learning in physics classrooms. Both ``Tutorials in Introductory Physics'' (Pearson, 2002) and ``Physics by Inquiry'' (Wiley, 1996) have been developed in an iterative process in which ongoing assessment of student learning plays an integral role. These materials have had a widespread and significant impact on physics teaching and on student learning from kindergarten through graduate school. In this talk I will describe the role of research in curriculum development, and speculate on the next generation of tools and resources to support physics teaching and learning.

  17. Proceedings, Conference on the Defense Planning, Programming, and Budgeting System (PPBS): Past, Present, and Future Held at Washington, DC on 4-6 November 1982

    Science.gov (United States)

    1982-11-06

    They are reviewed by the Deputy Chief of Staff for Installations and Logistics to de - The DC/S for manpower then goes on to a termine the logistica ...analyses have manages its programming process. concentrated on such innovations as the De - fense Resources Board and Defense Guidance. * Discussions of... transport that fighting force to the every student of any kind of management at all beach or into battle, then all of General would say that if you

  18. 75 FR 32736 - Notice of Solicitation for Members of the National Agricultural Research, Extension, Education...

    Science.gov (United States)

    2010-06-09

    ... Independence Avenue, SW., Room 321-A, Whitten Building, Washington, DC 20250-0321. FOR FURTHER INFORMATION... Economics Advisory Board, 1400 Independence Avenue, SW., Room 321-A, Whitten Building, Washington, DC 20250... research, crop and animal science, land-grant institutions, non-land grant college or university with a...

  19. 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…

  20. Proceedings of public hearings: plutonium and the other transuranium elements, Washington, D.C., December 10--11, 1974. Volume 1

    International Nuclear Information System (INIS)

    1974-01-01

    The Environmental Protection Agency embarked on a program to evaluate the environmental impact of the transuranium elements and to consider whether further guidelines or standards are needed to assure adequate protection of the general ambient environment and of the public health from potential contamination of the environment by radionuclides of these elements. Public hearings were held in Washington, D. C., and Denver, Colorado, to gather information regarding the public and social implications of plutonium utilization; the factors involved in the balancing of costs vs benefits; dosimetry, health, and environmental effects; environmental levels and pathways; applications using plutonium; and control and cleanup technology. The proceedings of the hearing in Washington, D. C., Dec. 10-11, 1974, are presented. Data are included on current and potential sources of transuranium elements in the environment; animal studies on the tissue distribution of 233 U, 237 Np, 238 Pu, 239 Pu, 241 Am, 244 Cm, 249 Bk, 252 Cf, and 253 Es and pathological effects of body burdens of these radionuclides; and data on the health status of personnel known to have body burdens of 238 Pu or 239 Pu acquired during acute or chronic exposure, many of them over 30 years previously. It is pointed out that the lack of demonstrable biological effects of Pu in man provides presumptive evidence that the radiation protection standards in effect are adequate. (U.S.)

  1. 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...

  2. Application research of power allocation based on Buck circuit in DC microgrid

    OpenAIRE

    Wang Zihao; Zhou Mingyu

    2017-01-01

    In a traditional DC microgrid, the power sharing control strategy has been always used in the distributed power converters, resulting in not making outer power allocation arbitrarily. In order to solve the power output allocation problem of wind power in DC microgrid, the intelligent Buck circuit based on PI algorithm and the load current feed-forward method was used to realize the arbitrary regulation of the output power of the wind power in the DC microgrid system. Compared with traditional...

  3. DC systems design and research of Hainan Changjiang nuclear power plant

    International Nuclear Information System (INIS)

    Jiang Qingshui; Wang Yuhan

    2014-01-01

    Hainan Changjiang nuclear power plant is different from the referent power plant, the DC and 220 V AC uninterrupted systems of the nuclear island have been changed since the control system use DCS. It has different design on DC systems, power supply, selectivity of breakers, capacity of equipments and layout. We optimize the design of DC systems at the basement of Fuqing and Fangjiashan project. These are good experiments for the three generation nuclear power project about DC systems design of ACP1000. (authors)

  4. Location | Frederick National Laboratory for Cancer Research

    Science.gov (United States)

    The Frederick National Laboratory for Cancer Research campus is located 50 miles northwest of Washington, D.C., and 50 miles west of Baltimore, Maryland, in Frederick, Maryland. Satellite locations include leased and government facilities extending s

  5. Iron, folacin, vitamin B12 and zinc status and immune response in elderly subjects in the Washington D.C. metropolitan area

    International Nuclear Information System (INIS)

    Henry-Christian, J.R.

    1986-01-01

    The iron, folacin, vitamin B 12 , and zinc status of a group of economically and socially disadvantaged elderly persons in the Washington Metropolitan Area was evaluated. Factors related to deficiencies of these nutrients, the relationships between the status of these nutrients and cell-mediated immunity, and the relationships of iron, folacin and vitamin B 12 status to hemoglobin levels in the subjects were also examined. It was also determined whether there were any interactions among iron, folacin, vitamin B 12 and zinc status in their relationships to cell-mediated immunity. Socio-demographic and nutritional data on the subjects were obtained using a questionnaire. Dietary data were obtained using a dietary record. A fasting blood sample was drawn and the levels of ferritin, folate and vitamin B 12 , and the erythrocyte levels of folate were determined by radioassay. Plasma and hair zinc levels were determined by atomic absorption spectrophotometry. Cell-mediated immune response was determined by transformation of peripheral blood lymphocytes after stimulation by mitogens, and by allogenic lymphocytes in the mixed lymphocyte reaction

  6. A Research Design for Library Cooperative Planning and Action in the Washington, D.C. Metropolitan Area.

    Science.gov (United States)

    Booz Allen and Hamilton, Inc., Washington, DC.

    The development of interlibrary cooperation in the National Capitol Area is not a simple task. The multiple, complex relations of governments on varying levels and the existence and independent sponsorship of important private association, industrial, academic and other libraries impose severe problems for any cooperative movement. A far-reaching…

  7. Mixed Methods in Education Research. IES Technical Working Group Meeting. Meeting Summary (Washington, DC, May 29, 2015)

    Science.gov (United States)

    Institute of Education Sciences, 2015

    2015-01-01

    This meeting summary is organized into two major sections. The first section captures the individual contribution of meeting participants, including both Institute of Education Sciences (IES) staff and the invited technical working group members. The second section captures themes that arose during the group discussions, which were organized…

  8. Turning State Data and Research into Information: An Example from Washington State's Student Achievement Initiative

    Science.gov (United States)

    Prince, David; Seppanen, Loretta; Stephens, Deborah; Stewart, Carmen

    2010-01-01

    This chapter discusses Washington State's Student Achievement Initiative, a new performance funding system for community and technical colleges. Its purposes are to improve public accountability by more accurately describing what students achieve from enrolling in state colleges each year and provide incentives through financial rewards to…

  9. Research

    African Journals Online (AJOL)

    abp

    2013-03-11

    Mar 11, 2013 ... From a practical point of view, apart from the data on age that are easily obtained from recorded ..... Washington D.C. : Academy for Educational Development 2003. ... learning: data mining, inference and prediction. New York:.

  10. Research

    African Journals Online (AJOL)

    abp

    2017-10-19

    Oct 19, 2017 ... Methods: in October 2014, we interviewed a total of 430 women selling in the central market of Lusonga in Lubumbashi. Data on ..... Washington, DC: Academy for Educational Development, Food ... Accessed March 27, 2014.

  11. Research on DC-RF superconducting photocathode injector for high average power FELs

    International Nuclear Information System (INIS)

    Zhao Kui; Hao Jiankui; Hu Yanle; Zhang Baocheng; Quan Shengwen; Chen Jiaer; Zhuang Jiejia

    2001-01-01

    To obtain high average current electron beams for a high average power Free Electron Laser (FEL), a DC-RF superconducting injector is designed. It consists of a DC extraction gap, a 1+((1)/(2)) superconducting cavity and a coaxial input system. The DC gap, which takes the form of a Pierce configuration, is connected to the 1+((1)/(2)) superconducting cavity. The photocathode is attached to the negative electrode of the DC gap. The anode forms the bottom of the ((1)/(2)) cavity. Simulations are made to model the beam dynamics of the electron beams extracted by the DC gap and accelerated by the superconducting cavity. High quality electron beams with emittance lower than 3 π-mm-mrad can be obtained. The optimization of experiments with the DC gap, as well as the design of experiments with the coaxial coupler have all been completed. An optimized 1+((1)/(2)) superconducting cavity is in the process of being studied and manufactured

  12. Residential Energy Efficiency Research Planning Meeting Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    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.

  13. Researchers active in two recent international tribology conferences

    OpenAIRE

    Nystrom, Lynn A.

    2005-01-01

    Virginia Tech faculty and former graduate students, in collaboration with researchers in Poland and Sweden, co-authored five papers presented at the international World Tribology Congress III held in Washington, D.C.

  14. 22 CFR Appendix D to Part 62 - Annual Report-Exchange Visitor Program Services (GC/V), Department of State, Washington, DC 20547...

    Science.gov (United States)

    2010-04-01

    ... proposed new activity, cross-cultural activities, as well as the reciprocal component of the program. I... Number Professor ____ Research Scholar ____ Short-term Scholar ____ Trainee ____ Student (College and...

  15. Research of Compound Control for DC Motor System Based on Global Sliding Mode Disturbance Observer

    Directory of Open Access Journals (Sweden)

    He Zhang

    2014-01-01

    Full Text Available Aiming at the problems of modeling errors, parameter variations, and load moment disturbances in DC motor control system, one global sliding mode disturbance observer (GSMDO is proposed based on the global sliding mode (GSM control theory. The output of GSMDO is used as the disturbance compensation in control system, which can improve the robust performance of DC motor control system. Based on the designed GSMDO in inner loop, one compound controller, composed of a feedback controller and a feedforward controller, is proposed in order to realize the position tracking of DC motor system. The gains of feedback controller are obtained by means of linear quadratic regulator (LQR optimal control theory. Simulation results present that the proposed control scheme possesses better tracking properties and stronger robustness against modeling errors, parameter variations, and friction moment disturbances. Moreover, its structure is simple; therefore it is easy to be implemented in engineering.

  16. Application research of power allocation based on Buck circuit in DC microgrid

    Directory of Open Access Journals (Sweden)

    Wang Zihao

    2017-01-01

    Full Text Available In a traditional DC microgrid, the power sharing control strategy has been always used in the distributed power converters, resulting in not making outer power allocation arbitrarily. In order to solve the power output allocation problem of wind power in DC microgrid, the intelligent Buck circuit based on PI algorithm and the load current feed-forward method was used to realize the arbitrary regulation of the output power of the wind power in the DC microgrid system. Compared with traditional distributed generators power-sharing method, the simulation and experimental results show the proposed method can realize arbitrary power outputting from distributed generators. Finally, the simulation and experimental results prove the validity and effectiveness of the control method.

  17. Research on current sharing of paralleled IGBTs in different DC breaker circuit topologies

    Directory of Open Access Journals (Sweden)

    Chen Ying

    2016-01-01

    Full Text Available IGBT modules used in series and parallel to satisfy the requirement in high-power DC circuit breakers are often prone to large-current destruction due to current unbalance between paralleled IGBTs. It is of great importance to identify the current unbalance causes and to find a method optimizing the current sharing of paralleled IGBTs. In this paper the current-sharing influencing factors are discussed and verified by simulation. Two possible circuit topologies used in DC circuit breakers are proposed and simulated to see their performance in current sharing. The results show that one of them can provide us with a simple and effective method to achieve good current balancing in the DC circuit breaker application.

  18. Research on Control System of Three - phase Brushless DC Motor for Electric Vehicle

    Science.gov (United States)

    Wang, Zhiwei; Jin, Hai; Guo, Jie; Su, Jie; Wang, Miao

    2017-12-01

    In order to study the three-phase brushless motor control system of electric vehicle, Freescale9S12XS128 chip is used as the control core, and the power MOSFET is used as the inverter device. The software is compiled by Codewarrior software. The speed control link adopts open-loop control, and the control chip collects the external sensor signal voltage Change control PWM signal output control three-phase brushless DC motor speed. The whole system consists of Hall position detection module, current detection module, power drive module and voltage detection module. The basic functions of three-phase brushless DC motor drive control are realized.

  19. Advanced DC/DC converters

    CERN Document Server

    Luo, Fang Lin

    2003-01-01

    DC/DC conversion techniques have undergone rapid development in recent decades. With the pioneering work of these authors, DC/DC converters have now moved into their sixth generation. This book offers a concise, practical presentation of DC/DC converters, summarizing the spectrum of conversion tecnologies and presentingmany new ideas and more than 100 new topologies. Nowhere else in the literature are DC/DC converters so logically sorted and systematically introduced, and nowhere else can readers find detailed information on prototype topologies that represent a major contribution to modern power engineering. More than 320 figures, 60 tables, and 500 formulae facilitate understand and provide precise data.

  20. Proceedings of the Conference: Communicative Problems in Cleft Palate (Washington, D.C., July 10-12, 1963). American Speech and Hearing Association Reports, Number 1.

    Science.gov (United States)

    Green, Diane, Ed.

    Introductory material by Jack Matthews points out common interests between the fields of dentistry and communication disorders. Physical aspects of cleft palate are explored in papers concerning anatomy and growth, by Robert F. Hagerty; infant respiratory actions, by James F. Bosma, H.M. Truby, and John Lind; contemporary dental research, by…

  1. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (84th, Washington, DC, August 5-8, 2001). History Division.

    Science.gov (United States)

    Association for Education in Journalism and Mass Communication.

    The History section of the proceedings contains the following 15 selected papers: "Attacking the Messenger: The Cartoon Campaign against 'Harper's Weekly' in the Election of 1884" (Harlen Makemson); "Fact or Friction: The Research Battle behind Advertising's Creative Revolution, 1958-1972" (Patricia M. Kinneer); "Bee So…

  2. Quarterly Report to the New Energy and Industrial Technology Development Organization, Washington, D.C., by Analysis Review and Critique, dated August 23, 1990

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-08-23

    Reports are made on U.S. Department of Energy activities relative to energy conservation, renewable energy, initiatives, Superconducting Super Collider, and national energy strategy. The Department in January 1990 announced an energy conservation/renewable energy research and development program comprising 11 initiatives, which are energy saving of more than 25% by relighting federal facilities, energy saving of more than 25% by relighting commercial buildings, integrated resource planning, accelerated building guidelines and standards relative to air-conditioning, etc., energy analysis and diagnostics for industrial facilities, energy production from municipal waste, manufacturing technology for photovoltaics, cost-competitive ethanol fuels, solar detoxification of hazardous waste, new laboratory building at SERI (Solar Energy Research Institute), and expanding hydropower contribution. Congress approved the Superconducting Super Collider project for fiscal 1990, and the accelerator is now proceeding to its construction phase. (NEDO)

  3. The Proceedings of the International Conference on Numerical Ship Hydrodynamics (4th) Held in Washington, DC on 24-27 September 1985

    Science.gov (United States)

    1985-09-01

    Arlington VA, U.S.A. M.R. Hendenhall and S.C. Perkins, PREDICTION OF THE UNSTEADY HYDRODYNAMIC CHARACTERISTICS OF SUBNERSIBLE VEHICLES ...Architecture and Ocean Engineering University of Glasgow Glasgow, Scotland Abstract Research into slamming on marine vehicles has concentrated in the two...difference (open boun- compare the results obtained by the dary) method (17], hibrid method of - method on the assumption of the linear matching with the

  4. Proceedings of the Interservice/Industry Training Equipment Conference (5th) Held at Washington, DC on November 14-16, 1983. Volume 1.

    Science.gov (United States)

    1983-11-16

    raised that commercial airline simulators of C) comparable quality can be procured for less money and with shorter schedules. This paper0 provides a...the element of surprise to evade hostile tion and Research ( LAUDER ) study was initiated to threats. The crew of toddy’s tactical and stra- examine...management must be secured. Extensive travel is typically a requirement of user support to the software generation process. Additionally, front-end money

  5. PharMillenium '99--the second world pharmaceutical congress and exhibition. Accelerating the pipeline: from drug discovery to market. 1-3 February 1999, Washington DC, USA.

    Science.gov (United States)

    Fernandes, M

    1999-04-01

    This highly interactive meeting effectively covered critical issues on every transaction from drug discovery through to development and commercialization. The program included company-specific descriptions of new discovery products, together with seminars by clinical research and site management organizations on the acceleration of development, pharmaco-economics, branding of products, direct-to-consumer advertising, global marketing, management, information technology and business strategy. There were approximately 50 sessions covered by 70 speakers.

  6. Proceedings of the Annual Meeting of the American Society of Tropical Medicine and Hygiene (37th) Held in Washington, D.C. on December 4-8, 1988

    Science.gov (United States)

    1988-12-30

    Naval Medical Research Institute Detachment, Lima, PERU ; Universidad Peruana Cayetano Heredia, Lima, PERU . 92 ETIOLOGY OF FEVERS OF UNKNOWN ORIGIN IN...Colorado State University, Department of Environmental Health, Ft. Collins, CO. 10:30 138 HANTAVIRUS INFECTIONS IN HUMANS AND COMMENSAL RODENTS IN... AMAZON BASIN, BRASIL. M.E. Arruda,* A.H. Cochrane, E.H. Nardin and R.S. Nussenzweig. Department of Entomology, Oswaldo Cruz Foundation, Rio de

  7. Scientific Grand Challenges: Discovery In Basic Energy Sciences: The Role of Computing at the Extreme Scale - August 13-15, 2009, Washington, D.C.

    Energy Technology Data Exchange (ETDEWEB)

    Galli, Giulia [Univ. of California, Davis, CA (United States). Workshop Chair; Dunning, Thom [Univ. of Illinois, Urbana, IL (United States). Workshop Chair

    2009-08-13

    The U.S. Department of Energy’s (DOE) Office of Basic Energy Sciences (BES) and Office of Advanced Scientific Computing Research (ASCR) workshop in August 2009 on extreme-scale computing provided a forum for more than 130 researchers to explore the needs and opportunities that will arise due to expected dramatic advances in computing power over the next decade. This scientific community firmly believes that the development of advanced theoretical tools within chemistry, physics, and materials science—combined with the development of efficient computational techniques and algorithms—has the potential to revolutionize the discovery process for materials and molecules with desirable properties. Doing so is necessary to meet the energy and environmental challenges of the 21st century as described in various DOE BES Basic Research Needs reports. Furthermore, computational modeling and simulation are a crucial complement to experimental studies, particularly when quantum mechanical processes controlling energy production, transformations, and storage are not directly observable and/or controllable. Many processes related to the Earth’s climate and subsurface need better modeling capabilities at the molecular level, which will be enabled by extreme-scale computing.

  8. Quarterly Report to the New Energy and Industrial Technology Development Organization, Washington, D.C., by Analysis Review and Critique, dated December 19, 1991

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-12-19

    The fiscal 1992 appropriations for solar and renewable energy research and development and the establishment of a National Renewable Energy Laboratory are reported. The fiscal 1992 request that the Bush Administration made to Congress for renewable energy was four percent higher than what Congress had appropriated for fiscal 1991. The amount that Congress finally approved was 24 percent more than what the Bush Administration had requested. Appropriations for renewable energy are increasing at a sharp rate: $110.5 million in fiscal 1990, $157.5 million in fiscal 1991, and $203.7 million in fiscal 1992. Solar building technology, comprising energy supply and energy conservation, received $5.504 million in fiscal 1991 and $4.372 million in 1992. Appropriations for photovoltaic research and development are increasing at a fast pace: $34.332 million in fiscal 1990, $46.307 million in fiscal 1991, and $60.400 million in fiscal 1992. President Bush on September 16, 1991, designated the Solar Energy Research Institute (SERI) a national laboratory. Its new name is the National Renewable Energy Laboratory (NREL). (NEDO)

  9. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications

    DEFF Research Database (Denmark)

    Schiffman, Eric; Ohrbach, Richard; Truelove, Edmond

    2014-01-01

    of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. RESULTS: The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting...

  10. Water quality in the Anacostia River, Maryland and Rock Creek, Washington, D.C.: Continuous and discrete monitoring with simulations to estimate concentrations and yields of nutrients, suspended sediment, and bacteria

    Science.gov (United States)

    Miller, Cherie V.; Chanat, Jeffrey G.; Bell, Joseph M.

    2013-01-01

    Concentrations and loading estimates for nutrients, suspended sediment, and E. coli bacteria were summarized for three water-quality monitoring stations on the Anacostia River in Maryland and one station on Rock Creek in Washington, D.C. Both streams are tributaries to the Potomac River in the Washington, D.C. metropolitan area and contribute to the Chesapeake Bay estuary. Two stations on the Anacostia River, Northeast Branch at Riverdale, Maryland and Northwest Branch near Hyattsville, Maryland, have been monitored for water quality during the study period from 2003 to 2011 and are located near the shift from nontidal to tidal conditions near Bladensburg, Maryland. A station on Paint Branch is nested above the station on the Northeast Branch Anacostia River, and has slightly less developed land cover than the Northeast and Northwest Branch stations. The Rock Creek station is located in Rock Creek Park, but the land cover in the watershed surrounding the park is urbanized. Stepwise log-linear regression models were developed to estimate the concentrations of suspended sediment, total nitrogen, total phosphorus, and E. coli bacteria from continuous field monitors. Turbidity was the strongest predictor variable for all water-quality parameters. For bacteria, water temperature improved the models enough to be included as a second predictor variable due to the strong dependence of stream metabolism on temperature. Coefficients of determination (R2) for the models were highest for log concentrations of suspended sediment (0.9) and total phosphorus (0.8 to 0.9), followed by E. coli bacteria (0.75 to 0.8), and total nitrogen (0.6). Water-quality data provided baselines for conditions prior to accelerated implementation of multiple stormwater controls in the watersheds. Counties are currently in the process of enhancing stormwater controls in both watersheds. Annual yields were estimated for suspended sediment, total nitrogen, total phosphorus, and E. coli bacteria using

  11. Attitudes, perceptions, and behaviors toward HIV testing among African American and East African immigrant women in Washington, D.C.: Implications for targeted HIV testing promotion and communication strategies

    Science.gov (United States)

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

    2015-01-01

    Objectives The objective of the study was to examine and compare the HIV testing attitudes, perceptions, and behaviors between African American and East African immigrant women in the Washington, D.C. Metropolitan area. Methods Adopting an inductive, qualitative methodological approach, we conducted a total of 40 in-depth, semi-structured interviews between October 2012 and March 2013. Qualitative thematic analysis was used to analyze the data. Results Overall, African American women held more favorable views toward 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- or employment-related purposes. There were many barriers that impede women from seeking an HIV test including: negative assumptions (e.g., ‘Getting an HIV test implies that I am HIV positive’); negative emotions (e.g., ‘Fear of being diagnosed with HIV and what this will mean for me’); and potential negative reactions from partner or others (e.g., ‘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. Conclusions 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. PMID:25897146

  12. Quarterly Report to the New Energy and Industrial Technology Development Organization, Washington, D.C., by Analysis Review and Critique. Report No. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-01-30

    The history of the US Federal Government programs on research and development of renewable energy and the status of development as of 1990 are stated. Described are the fields in which funds have been invested, objectives and goals of development, and the levels of efforts dedicated to development. Special remarks involve the US Department of Energy and its activities. First, policy and philosophy of the recovery energy programs and general objectives are summarized. Trends in the Federal Government budget and the basic system of the Department of Energy are also shown. Next, seven programs which respectively cover solar buildings (passive/active solar heating/cooling), solar thermal, wind energy, biofuels and municipal waste, ocean energy, geothermal energy, and photovoltaics are described. Every one of the seven programs consists of the background (technology, effect of energy), industry status, program goal and objective, budget (especially for main technology development), priority and future direction, and an appendix. (NEDO)

  13. Quarterly Report to the New Energy and Industrial Technology Development Organization, Washington, D.C., by Analysis Review and Critique, dated March 21, 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-21

    The fiscal 1995 budge request of the Clinton Administration Department of Energy for renewable energy research and development is reported. Solar energy receiving $186.2 million in fiscal 1993 and $252.3 million in 1994 is to be funded $301.1 million in fiscal 1995. Geothermal energy receiving $23.3 million in fiscal 1993 and $24.0 million in fiscal 1994 is to be funded $37.2 million. When hydropower is added to the above two, the request for 1995 amounts to $339.3 million, or $61.9 million over the preceding fiscal year. The renewable energy budget request has three features: use of the keyword 'market mobilization' in line with the Climate Change Action Plan made public in October 1993; increased use of terms such as NADET (National Advanced Drilling and Excavation Technologies) program, Solar-MAT, GT-WORLD, and so forth; and respondence to requirements established in the Energy Policy Act of fiscal 1992 and listing of performance criteria for identification of program parts that can be labelled 'investment.' (NEDO)

  14. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    OpenAIRE

    Jian-ping Wen; Chuan-wei Zhang

    2015-01-01

    In order to improve energy utilization rate of battery-powered electric vehicle (EV) using brushless DC machine (BLDCM), the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO) to observe actual braking current and the unknown disturbances of regenerative braking system, ...

  15. Research & Implementation of AC - DC Converter with High Power Factor & High Efficiency

    Directory of Open Access Journals (Sweden)

    Hsiou-Hsian Nien

    2014-05-01

    Full Text Available In this paper, we design and develop a high power factor, high efficiency two-stage AC - DC power converter. This paper proposes a two-stage AC - DC power converter. The first stage is boost active power factor correction circuit. The latter stage is near constant frequency LLC resonant converter. In addition to traditional LLC high efficiency advantages, light-load conversion efficiency of this power converter can be improved. And it possesses high power factor and near constant frequency operating characteristics, can significantly reduce the electromagnetic interference. This paper first discusses the main structure and control manner of power factor correction circuit. And then by the LLC resonant converter equivalent model proceed to circuit analysis to determine the important parameters of the converter circuit elements. Then design a variable frequency resonant tank. The resonant frequency can change automatically on the basis of the load to reach near constant frequency operation and a purpose of high efficiency. Finally, actually design and produce an AC – DC power converter with output of 190W to verify the characteristics and feasibility of this converter. The experimental results show that in a very light load (9.5 W the efficiency is as high as 81%, the highest efficiency of 88% (90 W. Full load efficiency is 87%. At 19 W ~ 190 W power changes, the operating frequency change is only 0.4 kHz (AC 110 V and 0.3 kHz (AC 220 V.

  16. Nuclear non-proliferation and arms control: Are we making progress? 7 November 2005, Washington, DC, Carnegie International Non-Proliferation Conference

    International Nuclear Information System (INIS)

    ElBaradei, M.

    2005-01-01

    ) establish a framework for multilateral management and control of the 'back end' of the fuel cycle (i.e. spent fuel reprocessing and waste disposal); and 4) create a similar framework for multilateral management and control of the 'front end' of the fuel cycle (i.e. enrichment and fuel production). Regarding the protection of nuclear material it is reported that multiple international and regional initiatives are underway to help countries to improve the physical protection of such material. The International Convention on the Suppression of Acts of Nuclear Terrorism was adopted by the UN General Assembly in April 2005. Many governments have also responded to UN Security Council resolution 1540, adopted in April 2004. Both the Convention and resolution 1540 call on countries to criminalize the illicit possession and use of radioactive material, and aim to enhance efforts to detect and combat illicit trafficking. And in July, parties to the Convention on the Physical Protection of Nuclear Material agreed on major changes that would make it legally binding for countries to protect nuclear facilities and material in domestic use, storage and transport. With strong support from the IAEA, Russia and the US, multiple countries are also taking steps to convert their research reactors from HEU to LEU fuel, and to return the HEU to the country of origin. For nuclear non-proliferation commitments to be effective, they must be backed by credible mechanisms to deal with cases of compliance. The potential for being referred to the UN Security Council has clearly acted as an inducement for compliance in some cases; however, we should recall that the referral of North Korea to the Council, in 1992 and again in 2003, resulted in little to no action. To be effective, the UN Security Council must be ready at all times to engage, in order to cope with emerging threats to international peace and security. On the nuclear disarmament front, no mechanism exists to monitor compliance with

  17. The life test of a DC circuit breaker of tokamak device JT-60 for a nuclear fusion research

    International Nuclear Information System (INIS)

    Shimada, Ryuichi; Tani, Keiji; Kishimoto, Hiroshi; Tamura, Sanae; Yanabu, Satoru.

    1979-01-01

    In the Tokamak devices for nuclear fusion research, the construction of the current transformer circuits having plasma as the secondary circuit and the change of the primary circuit current are necessary for generating current in the plasma. This is considered to be fairly difficult in practice if conventional methods using capacitor discharge and iron core coils are employed. Considering such circumstances, it was decided for JT-60 to use an air-core current transformer coil and to employ the method of storing energy in the form of current in the coil inductance instead of a capacitor. For this reason, a DC circuit breaker is required to interrupt coil current. The authors improved an AV vacuum breaker, which had been developed as the vacuum breaker of longitudinal magnetic field type applying a magnetic field in parallel with an arc, to get the one for DC circuit for the purpose of applying it to JT-60. In this paper, the operational characteristic of the DC breaker is described, the construction and function of the life test circuit is explained, and the test results are reported. Finally, interruptions of 10,000 times at 20 kA were carried out. It is successful that the restrike of arc occurring during tens of milli-seconds after interruptions was improved to 0.05% or less for 10,000 times operations. Further, it was found that the generation of arc restrike can be reduced practically to zero with two breakers in series. (Wakatsuki, Y.)

  18. 75 FR 61025 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order...

    Science.gov (United States)

    2010-10-01

    ... Information Order; Referendum Procedures AGENCY: Agricultural Marketing Service, USDA. ACTION: Proposed rule..., Washington, DC 20503. FOR FURTHER INFORMATION CONTACT: Maureen T. Pello, Marketing Specialist, Research and... procedure, Advertising, Consumer information, Marketing agreements, Softwood Lumber, Promotion, Reporting...

  19. Socrates in Washington, D.C.

    Science.gov (United States)

    2008-08-01

    neoclassical architecture , his flowing robes practically blended in. At any rate, he didn’t get more than a passing glance from the pedes- trians and...American cinema and TV. “And I do believe it was this same Hawkeye who said, ‘If we don’t go crazy once in a while, we’ll all go crazy.’” We settled down

  20. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jian-ping Wen

    2015-01-01

    Full Text Available In order to improve energy utilization rate of battery-powered electric vehicle (EV using brushless DC machine (BLDCM, the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO to observe actual braking current and the unknown disturbances of regenerative braking system, the autodisturbances rejection controller (ADRC for controlling the braking current is developed. Experimental results show that the proposed method gives better recovery efficiency and is robust to disturbances.

  1. 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.

  2. Recent developments: Washington focus

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    November was a quiet month in Washington. Although Congress has recessed until 1991, the Senate filled vacancies in party leadership positions created by November's elections. The House is expected to proceed with its changes in early December. The Nuclear Energy Forum was held in Washington, DC on November 11-14 to discuss the status of the nuclear industry in the USA. The Forum, held in conjunction with the American Nuclear Society's annual meeting, assembled a large number of CEO's from US, European, and Far Eastern utilities and vendors. The meeting concluded with an announcement by Philip Bayne, President of NYPA and chairman of the Nuclear Power Oversight Committee (NPOC), of the results of a year-long NPOC study entitled a open-quotes Strategic Plan for Building New Nuclear Power Plants.close quotes

  3. Financial implications of the accident at Three Mile Island. Oversight hearings before the Committee on Interior and Insular Affairs, House of Representatives, Ninety-Seventh Congress, First Session on financial implications of the accident at Three Mile Island, hearings held in Washington, DC, May 4-5, 1981

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Five panel presentations and a total of 21 witnesses testified at a two-day hearing May 4-5, 1981, in Washington, DC, on the financial consequences of the Three Mile Island (TMI) accident and the economic issues of the cleanup. The committee's goal was to listen to recommendations for government response and to determine the government's proper role and whether legislation is necessary to fulfill that role. Another issue under consideration was the restart of the undamaged unit one. The hearing record includes testimony of witnesses representing the nuclear power industry, environmental groups, and the financial and insurance industries and three appendices with additional materials

  4. Workshop on environmental research for transuranic elements, Seattle, Washington, November 12--14, 1975

    International Nuclear Information System (INIS)

    1975-01-01

    Brief summaries are presented of discussions among scientists conducting research on the transport and diffusion of transuranium elements in aquatic and terrestrial ecosystems. Emphasis was placed on 238 Pu, 239 Pu, 240 Pu, and 241 Am in ecosystems and food chains. Areas for future research were suggested to insure the safe storage of radioactive wastes from the nuclear industry

  5. Procurement of Human Tissues for Research Banking in the Surgical Pathology Laboratory: Prioritization Practices at Washington University Medical Center

    Science.gov (United States)

    Chernock, Rebecca D.; Leach, Tracey A.; Kahn, Ajaz A.; Yip, James H.; Rossi, Joan; Pfeifer, John D.

    2011-01-01

    Academic hospitals and medical schools with research tissue repositories often derive many of their internal human specimen acquisitions from their site's surgical pathology service. Typically, such acquisitions come from appropriately consented tissue discards sampled from surgical resections. Because the practice of surgical pathology has patient care as its primary mission, competing needs for tissue inevitably arise, with the requirement to preserve adequate tissue for clinical diagnosis being paramount. A set of best-practice gross pathology guidelines are summarized here, focused on the decision for tissue banking at the time specimens are macroscopically evaluated. These reflect our collective experience at Washington University School of Medicine, and are written from the point of view of our site biorepository. The involvement of trained pathology personnel in such procurements is very important. These guidelines reflect both good surgical pathology practice (including the pathologic features characteristic of various anatomic sites) and the typical objectives of research biorepositories. The guidelines should be helpful to tissue bank directors, and others charged with the procurement of tissues for general research purposes. We believe that appreciation of these principles will facilitate the partnership between surgical pathologists and biorepository directors, and promote both good patient care and strategic, value-added banking procurements. PMID:23386925

  6. Facilities for Study and Research in the Offices of the United States Government at Washington. Bulletin, 1909, No. 1. Whole Number 398

    Science.gov (United States)

    Hadley, Arthur Twining

    1909-01-01

    This bulletin contains a report prepared by President Hadley of Yale University on the facilities for advanced study and research in the offices of the National Government at Washington. Especial interest attaches to this publication. It sets forth, in compact form, information which has frequently been sought by institutions and individuals…

  7. Research on power equalization using a low-loss DC-DC chopper for lithium-ion batteries in electric vehicle

    Science.gov (United States)

    Wei, Y. W.; Liu, G. T.; Xiong, S. N.; Cheng, J. Z.; Huang, Y. H.

    2017-01-01

    In the near future, electric vehicle is entirely possible to replace traditional cars due to its zero pollution, small power consumption and low noise. Lithium-ion battery, which owns lots of advantages such as lighter and larger capacity and longer life, has been widely equipped in different electric cars all over the world. One disadvantage of this energy storage device is state of charge (SOC) difference among these cells in each series branch. If equalization circuit is not allocated for series-connected batteries, its safety and lifetime are declined due to over-charge or over-discharge happened, unavoidably. In this paper, a novel modularized equalization circuit, based on DC-DC chopper, is proposed to supply zero loss in theory. The proposed circuit works as an equalizer when Lithium-ion battery pack is charging or discharging or standing idle. Theoretical analysis and control method have been finished, respectively. Simulation and small scale experiments are applied to verify its real effect.

  8. Milliwatt dc/dc Inverter

    Science.gov (United States)

    Mclyman, C. W.

    1983-01-01

    Compact dc/dc inverter uses single integrated-circuit package containing six inverter gates that generate and amplify 100-kHz square-wave switching signal. Square-wave switching inverts 10-volt local power to isolated voltage at another desired level. Relatively high operating frequency reduces size of filter capacitors required, resulting in small package unit.

  9. TOPOLOGICAL REVIEW AND ANALYSIS OF DC-DC BOOST CONVERTERS

    Directory of Open Access Journals (Sweden)

    V. INDRA GANDHI

    2017-06-01

    Full Text Available DC voltage boost up is essential in numerous applications; especially considering Photovoltaic (PV based renewable power generation system. The conventional DC-DC boost converter is the most admired configuration for this scheme, even if the converter efficiency is restricted at duty cycle near to maximum value. In order to find solution to the problem and improve its conversion capability, many converter configurations have been implemented so far. With this circumstance, this research work proposes to give overview of a few most imperative research works related to DC-DC boost converters. Some configurations are covered and classified basically based on the application. The major benefits and disadvantages related to the available techniques are also briefly conveyed. At last, a proper evaluation is recognized among the important types of DC-DC boost converters in terms of efficiency, number of components, and stability.

  10. dc Arc Fault Effect on Hybrid ac/dc Microgrid

    Science.gov (United States)

    Fatima, Zahra

    The advent of distributed energy resources (DER) and reliability and stability problems of the conventional grid system has given rise to the wide spread deployment of microgrids. Microgrids provide many advantages by incorporating renewable energy sources and increasing the reliability of the grid by isolating from the main grid in case of an outage. AC microgrids have been installed all over the world, but dc microgrids have been gaining interest due to the advantages they provide over ac microgrids. However the entire power network backbone is still ac and dc microgrids require expensive converters to connect to the ac power network. As a result hybrid ac/dc microgrids are gaining more attention as it combines the advantages of both ac and dc microgrids such as direct integration of ac and dc systems with minimum number of conversions which increases the efficiency by reducing energy losses. Although dc electric systems offer many advantages such as no synchronization and no reactive power, successful implementation of dc systems requires appropriate protection strategies. One unique protection challenge brought by the dc systems is dc arc faults. A dc arc fault is generated when there is a gap in the conductor due to insulation degradation and current is used to bridge the gap, resulting in an arc with very high temperature. Such a fault if it goes undetected and is not extinguished can cause damage to the entire system and cause fires. The purpose of the research is to study the effect of the dc arc fault at different locations in the hybrid ac/dc microgrid and provide insight on the reliability of the grid components when it is impacted by arc faults at various locations in the grid. The impact of dc arc fault at different locations on the performance of the PV array, wind generation, and constant power loads (CPL) interfaced with dc/dc converters is studied. MATLAB/Simulink is used to model the hybrid ac/dc microgrid and arc fault.

  11. 75 FR 68686 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-9-14, DC-9-15, and DC-9-15F...

    Science.gov (United States)

    2010-11-09

    ... Jersey Avenue, SE., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Wahib Mina, Aerospace Engineer... requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Wahib Mina, Aerospace...

  12. Pulsewidth modulated DC-to-DC power conversion circuits, dynamics, and control designs

    CERN Document Server

    Choi, Byungcho

    2013-01-01

    This is the definitive reference for anyone involved in pulsewidth modulated DC-to-DC power conversion Pulsewidth Modulated DC-to-DC Power Conversion: Circuits, Dynamics, and Control Designs provides engineers, researchers, and students in the power electronics field with comprehensive and complete guidance to understanding pulsewidth modulated (PWM) DC-to-DC power converters. Presented in three parts, the book addresses the circuitry and operation of PWM DC-to-DC converters and their dynamic characteristics, along with in-depth discussions of control design of PWM DC-to

  13. "20 years of progress in highway safety" : verslag van the Eleventh International Technical Conference on Experimental Safety Vehicles ESV, Washington D.C., 12-15 May 1987 : achtergronden en overzicht van de ontwikkelingen tot juli 1988.

    NARCIS (Netherlands)

    Kampen, L.T.B. van

    1988-01-01

    A report of a visit to the 'eleventh international conference on experimental safety vehicles, washington, 12-15 may 1987' is given in this publication. Some of the technical papers presented at the conference are described and commented upon: (the opening address, the status reports and the panel

  14. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications

    DEFF Research Database (Denmark)

    Schiffman, Eric; Ohrbach, Richard; Truelove, Edmond

    2014-01-01

    AIMS: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥...... comprehensive instruments augment short and simple screening instruments for Axis I and Axis II. These validated instruments allow for identification of patients with a range of simple to complex TMD presentations....

  15. Research

    African Journals Online (AJOL)

    ebutamanya

    2 nov. 2015 ... Séraphin Nguefack1,2, Anderson Ngouo Tchiffo3, David Chelo2,4, ..... Stevenson et al [22], 38% des enfants IMC avaient un retard .... Krick J, Murphy-Miller P, Zeger S, Wright E. Pattern of growth ... Washington DC.2003.

  16. Children's Access to Health Insurance and Health Status in Washington State: Influential Factors. Research Brief. Publication #2009-21

    Science.gov (United States)

    Matthews, Gregory; Moore, Kristin Anderson; Terzian, Mary

    2009-01-01

    Health insurance, and especially coverage for children, has been a subject of recent political debate in Washington State, as well as on the national stage. Policy makers and health care providers can use high-quality state-level data to assess which children lack health insurance and devise possible solutions to address this need. Illustrating…

  17. Informing Science (IS and Science and Technology Studies (STS: The University as Decision Center (DC for Teaching Interdisciplinary Research

    Directory of Open Access Journals (Sweden)

    Teresa Castelao-Lawless

    2001-01-01

    Full Text Available Students of history and philosophy of science courses at my University are either naïve robust realists or naïve relativists in relation to science and technology. The first group absorbs from culture stereotypical conceptions, such as the value-free character of the scientific method, that science and technology are impervious to history or ideology, and that science and religion are always at odds. The second believes science and technology were selected arbitrarily by ideologues to have privileged world views of reality to the detriment of other interpretations. These deterministic outlooks must be challenged to make students aware of the social importance of their future roles, be they as scientists and engineers or as science and technology policy decision makers. The University as Decision Center (DC not only reproduces the social by teaching standard solutions to well-defined problems but also provides information regarding conflict resolution and the epistemological, individual, historical, social, and political mechanisms that help create new science and technology. Interdisciplinary research prepares students for roles that require science and technology literacy, but raises methodological issues in the context of the classroom as it increases uncertainty with respect to apparently self-evident beliefs about scientific and technological practices.

  18. Chemistry Research of Optical Fibers.

    Science.gov (United States)

    1982-09-27

    BROADENING IN OPTICAL FIBERS Herbert B. Rosenstock* Naval Research Laboratory Washington, DC 20375 ABSTRACT A light pulse transmitted through a fiber...Marcatili, Marcuse , and Personick, "Dispersion Properties of Fibers" (Ch. 4 in "Optical Fiber Telecommunications," S. E. Miller and A. C. Chynoweth, eds

  19. Financial Literacy and Education Research Priorities

    Science.gov (United States)

    Schuchardt, Jane; Hanna, Sherman D.; Hira, Tahira K.; Lyons, Angela C.; Palmer, Lance; Xiao, Jing Jian

    2009-01-01

    Twenty-nine scholars from public and private universities, non-profit organizations, and the federal government participated in a National Research Symposium on Financial Literacy and Education in October 2008 in Washington, DC. The purpose was to identify critical research questions that could inform outcomes-based financial education, relevant…

  20. 75 FR 10414 - Researcher Identification Card

    Science.gov (United States)

    2010-03-08

    ... capturing administrative information on the characteristics of our users. Other forms of identification are... use bar-codes on researcher identification cards in the Washington, DC, area. The plastic cards we... plastic researcher identification cards as part of their security systems, we issue a plastic card to...

  1. 2013 Building America Research Planning Meeting Summary

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hunt, S. [Confluence Communications, Missoula, MT (united States)

    2014-02-01

    The Building America Research Planning Meeting was held October 28-30, 2013, in Washington, DC. This meeting provides one opportunity each year for the research teams, national laboratories and Department of Energy (DOE) managers to meet in person to share the most pertinent information and collaboration updates. This report documents the presentations, highlights key program updates, and outlines next steps for the program.

  2. 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%.

  3. A Unidirectional DC-DC Autotransformer for DC Grid Application

    Directory of Open Access Journals (Sweden)

    Meng Zhou

    2018-03-01

    Full Text Available Conventional unidirectional DC-DC converters for DC grid application employ DC-AC-DC two-stage conversion technology and suffer from high converter cost and power loss. To solve these issues, a unidirectional step-up DC-DC autotransformer (UUDAT and a unidirectional step-down DC-DC autotransformer (DUDAT are studied. The UUDAT and DUDAT are composed of a series connection of diode bridges and voltage source converters. Topologies of UUDAT and DUDAT are detailed. The harmonic and un-controllability issues are discussed. Control and possible application scenarios for UUDAT and DUDAT are depicted. DC fault isolation mechanism and the methods of dimensioning the voltage and power ratings of the components in UUDAT and DUDAT are studied. Extensive simulations on power system level and experiments on a UUDAT and DUDAT prototype verified their technical feasibility.

  4. Selection of the DC-60 cyclotron as the basic facility for the Inter-disciplinary research complex in the L.N. Gumilev Eurasian State University. Chapter 2

    International Nuclear Information System (INIS)

    2003-01-01

    In the Chapter 2 the DC-60 specialized accelerator project of the Inter-disciplinary research complex in the L.N. Gumilev Eurasian State University is described. The DC-60 cyclotron is intended for applied studies which can be accomplished on both the ion beams of the electron cyclotron resonance source with voltage up to 25 kV and the accelerated ions from carbon to xenon. The cyclotron is design on the base of compact magnet with weight about 74 tonnes, and it mean magnetic field is 1.6 T, section angle - 50 Deg. Design of the Inter-disciplinary research complex building in the L.N. Gumilev Eurasian State University is described as well. Technical performances of the building and their parameters are given

  5. Drilling history core hole DC-4

    International Nuclear Information System (INIS)

    1978-12-01

    Core hole DC-4 was completed at a depth of 3998 feet in December, 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 Sicsson, Inc. furnished the engineering, daily supervision of the cable tool and core drilling activities, and geological core logging for DC-4. Core hole DC-4 is located on the Hanford Site about 3 miles east of the Yakima Barricade and approximately 103 feet southwest of rotary hole DC-5, which was completed to 3990 feet in February, 1978. Hanford Site coordinates reported for hole DC-4 are north 49,385.62 feet and west 85,207.63 feet, and Washington State coordinates are north 454,468.73 feet and east 2,209,990.87 feet. No elevation survey is available for hole DC-4, but it is approximately 745 feet above mean sea level based upon the survey of hole DC-5, which has a reported elevation of 745.16 feet on the top of the 3-inch flange. The purpose of core hole DC-4 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, cross-hole seismic shear, and pressure wave velocity studies with rotary hole DC-5. Hole DC-4 was drilled through the overburden into basalt bedrock by cable tool methods (0-623 feet) and continuously cored through the final interval (623 to 3998 feet).Core recovery was 95.8 percent of the total footage cored

  6. Drilling history core hole DC-8

    International Nuclear Information System (INIS)

    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

  7. 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.

  8. Washington Conference

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    The 1981 Particle Accelerator Conference was held in Washington from 11-13 March. It was the ninth in the series of meetings organized in the USA which differ from the 'International' meetings in their coverage of the full range of accelerator engineering and technology, including applications outside e field of high energy physics. The Conference took place under the cloud of further budget cuts for Fiscal Year 1982 in the USA which the Department of Energy has applied in line with the financial policy of the new administration. Coming on top of many years of budget trimming which have reduced the number of high energy physics Laboratories funded by the DOE to three (Brookhaven, Fermilab, Stanford - Cornell is funded by the National Science Foundation) and reduced the exploitation of these Laboratories to less than half of their potential, the new cuts did not exactly help to boost morale. Nevertheless, the huge amount of tailed work in accelerator physics and technology which was presented at the Conference showed how alive the field is

  9. El-AbedOroub, Unprotected: Palestinians in Egypt since 1948, Washington, DC, Institute for Palestine Studies / Ottawa: International Development Research Centre, 2009, 253 p.

    Directory of Open Access Journals (Sweden)

    Françoise de Bel-Air

    2010-06-01

    Full Text Available L’ouvrage proposé par Oroub El-Abed sur les Palestiniens d’Égypte comble un manque : cette communauté n’avait, en effet, encore jamais fait l’objet d’une étude scientifique de grande ampleur telle que celle entreprise par l’auteur sous les auspices du programme Forced Migration and Refugee Studies de l’Université américaine au Caire. L’ambition initiale de Oroub El-Abed et de son équipe était de réaliser une enquête de terrain portant sur un échantillon de 300 ménages répartis dans 15 gouvern...

  10. X-rays and Neutrons: Essential Tools for Nanoscience Research. Report of the National Nanotechnology Initiative Workshop, June 16-18, 2005, Washington, D.C.

    Science.gov (United States)

    2005-06-18

    structures: Left: Neutron diffraction profile of a monolayer butane film on magnesium oxide ( MgO ) nanocubes. (Copyright 2006 by the American Physical...bonding and catalyzed oxidation of CO on Au 8 clusters on MgO ,” Science 307(5708), 403– 407 (2005). doi:10.1126/science.1104168 X-rays and Neutrons...Understanding wetting phenomenon on nanostructured surfaces is crucial for enabling many emerging technologies, including nanofluidic , advanced lithographic

  11. Software Technology for Adaptable Reliable Systems (STARS) Workshop Held at the Naval Research Laboratory, Washington, DC on April 9-12 1985

    Science.gov (United States)

    1985-01-01

    Barrie Baston , MITRE Mike Glasgow, IBM Geoff Mendal, Lockheed LL :8: i::6:: 856 "_--’... ISSUES 1. Define forms and provide rationale for selection: a...George Mendal, Lockheed Missiles and Space Alan Blair, General Dynamics Steve Huseth, Honeywell Miguel Carrio, Teledyne Brown Engineering Barrie Baston

  12. 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...

  13. 75 FR 46903 - Forestry Research Advisory Council

    Science.gov (United States)

    2010-08-04

    ... Development, 1400 Independence Ave., SW., Washington, DC 20250-1120, or fax their names and proposed agenda... Deputy Chief for Research and Development, (202) 205-1665. Individuals who use telecommunication devices for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 1-800-877-8339 between 8 a...

  14. Original Research Original Research

    African Journals Online (AJOL)

    User

    2013-06-20

    Jun 20, 2013 ... Intimate partner violence against women undermine the well-being of women. Thus ...... Dares Salaam, Tanzania (Washington, DC: Horizons. Project/ICRW: 2000): ... GCWA_BG_Violence_en.pdf> [Accessed 11 march. 2008].

  15. 78 FR 78506 - Research and Development; Public Meeting

    Science.gov (United States)

    2013-12-26

    ... Safety R&D Initiatives on Packaging Testing Paperless Hazard Communications Pilot Program Odorization of.... PHMSA-2013-0261; Notice No. 13-21] Research and Development; Public Meeting AGENCY: Pipeline and... the Research and Development Forum to be held January 17, 2014, in Washington, DC. During this meeting...

  16. Frontiers in chemical engineering: research needs and opportunities

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Physical Sciences, Mathematics, and Applications; Division on Engineering and Physical Sciences; National Research Council

    1988-01-01

    ...: Research Needs and Opportunities Board on Chemical Sciences and Technology Commission on Physical Sciences, Mathematics, and Resources National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1988 i Copyrighttrue Please breaks inserted. are Page files. accidentally typesetting been have may original from the errors not typographic original ret...

  17. Use of Laboratory Animals in Biomedical and Behavioral Research

    National Research Council Canada - National Science Library

    1988-01-01

    ... of Laboratory Animals in Biomedical and Behavioral Research Commission on Life Sciences National Research Council Institute of Medicine NATIONAL ACADEMY PRESS Washington, D.C. 1988 Copyrightoriginal retained, the be not from cannot book, paper original however, for version formatting, authoritative the typesetting-specific created from the as publ...

  18. Russian delegation visits NIH and NCI to discuss research collaboration

    Science.gov (United States)

    The NCI Center for Global Health hosted a delegation from the Russian Foundation for Basic Research to discuss ongoing and future collaborations in cancer research. The delegation was accompanied by representatives from the US Embassy in Moscow and the Embassy of the Russian Federation in Washington DC.

  19. Assessment of research needs for wind turbine rotor materials technology

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Engineering and Technical Systems; Division on Engineering and Physical Sciences; National Research Council; National Academy of Sciences

    1991-01-01

    ... on Assessment of Research Needs for Wind Turbine Rotor Materials Technology Energy Engineering Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1991 Copyrightthe true use are Please breaks Page inserted. accidentally typesetting been have may original the from errors not...

  20. Reading Research Utilization Project: An RIC Project for Teachers and Other Field Personnel.

    Science.gov (United States)

    District of Columbia Public Schools, Washington, DC. Dept. of Research and Evaluation.

    This is the final report of the Reading Research Utilization Project (RUP) which was funded by the U.S. Office of Education from July, 1971 to June, 1973. The purpose of the RUP was to encourage the translation of research, particularly reading research, into practice in 16 target elementary schools in Washington, D.C. RUP was a school information…

  1. Father Secchi Goes to Washington

    Science.gov (United States)

    McCarthy, M. F.

    1994-12-01

    In 1848 a small group of Jesuit refugees arrived at Georgetown College near Washington, D.C. Among them was a young priest, Angelo Secchi, who had finished theology studies in Rome, but had not been able to complete his final examinations. This done successfully, Secchi turned to astronomy and the new facilities of the Georgetown College Observatory, directed by its founder, Fr. James Curley. During his two years in Washington, Secchi studied physics, wrote an article on Electrical Rheometry for the Smithsonian Institution, and formed a friendship with Matthew Fontaine Maury of the U.S. Navy, who headed the Chart Service and in 1844 was named superintendent of the National Observatory. This was later named the U.S. Naval Observatory. Secchi's friendships formed during the Washington visit proved most helpful for relations between European astronomers and U.S. colleagues. Secchi, after his return to Rome constructed the Observatory of the Collegio Romano atop the baroque Church of St. Ignatius in Rome and began his work in spectral classification of stars.

  2. 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......DC-DC converters with voltage boost capability are widely used in a large number of power conversion applications, from fraction-of-volt to tens of thousands of volts at power levels from milliwatts to megawatts. The literature has reported on various voltage-boosting techniques, in which......-boosting techniques and associated converters are discussed in detail. Finally, broad applications of dc-dc converters are presented and summarized with comparative study of different voltage-boosting techniques....

  3. 78 FR 2429 - Notice of Inventory Completion: The Museum of Anthropology at Washington State University...

    Science.gov (United States)

    2013-01-11

    ... construction. Archaeologists working for the Washington Archaeological Research Center at Washington State... Reservation. Historical, ethnographic, linguistic, and archaeological information links the site to the...

  4. 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...... and/or constant discharging for batteries is adopted and four operating modes are analyzed as charging-positive, charging-negative, discharging-positive and discharging-negative modes. An additional mechanism for fast charging or fast discharging is also designed to secure normal operation...... of batteries. With the proposed DCES, the power fluctuations due to intermittent RESs can be passed to non-critical loads (NCLs) and batteries while power on critical loads (CLs) is kept stable. This is possibly the first attempt to design a DCES with only DC/DC converters. The performances of the proposed...

  5. 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

  6. 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

  7. Chapter 2: Effects of climatic variability and change. In Effects of Climate Variability and Change on Forest Ecosystems: A Comprehensive Science Synthesis for the U.S. Forest Sector; General Technical Report PNW-GTR-870, Washington DC

    Science.gov (United States)

    Climate profoundly shapes forests. Forest species composition, productivity, availability of goods and services, disturbance regimes, and location on the landscape are all regulated by climate. Much research attention has focused on the problem of predicting the response of fores...

  8. The Competitive edge: research priorities for U.S. manufacturing

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Engineering and Technical Systems; Board on Manufacturing and Engineering Design; Division on Engineering and Physical Sciences; National Research Council; National Academy of Sciences

    1991-01-01

    ... Manufacturing Studies Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1991 i 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...

  9. Promoting health: intervention strategies from social and behavioral research

    National Research Council Canada - National Science Library

    Smedley, Brian D; Syme, S. Leonard

    ... on Capitalizing on Social Science and Behavioral Research to Improve the Public's Health Division of Health Promotion and Disease Prevention INSTITUTE OF MEDICINE NATIONAL ACADEMY PRESS Washington, D.C. i Copyrightthe cannot be not from book, paper however, version for formatting, original authoritative the typesetting-specific the as from created pu...

  10. CCR presentations at AACR | Center for Cancer Research

    Science.gov (United States)

    CCR presentations at AACR Several CCR scientists will present their research at the AACR Annual Meeting in Washington, D.C., between April 1-5, 2017. Selected oral presentations are listed below. A full list of abstracts can be found on the AACR website.

  11. 75 FR 55634 - National Research Advisory Council; Notice of Meeting

    Science.gov (United States)

    2010-09-13

    ... DEPARTMENT OF VETERANS AFFAIRS National Research Advisory Council; Notice of Meeting The Department of Veterans Affairs (VA) gives notice under Public Law 92-463 (Federal Advisory Committee Act... Phoenix Park Hotel, Federal City Room, 520 North Capitol Street, NW., Washington, DC. The meeting will...

  12. The competitive edge: research priorities for U.S. manufacturing

    National Research Council Canada - National Science Library

    National Research Council Staff; Commission on Engineering and Technical Systems; Board on Manufacturing and Engineering Design; Division on Engineering and Physical Sciences; National Research Council; National Academy of Sciences

    1991-01-01

    ... Manufacturing Studies Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1991 i 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...

  13. Research and service programs in the PHS: challenges in organization

    National Research Council Canada - National Science Library

    Institute of Medicine Staff; Institute of Medicine

    1991-01-01

    ... Committee on Co-Administration of Service and Research Programs of the National Institutes of Health, the Alcohol, Drug Abuse, and Mental Health Administration, and Related Agencies INSTITUTE OF MEDICINE NATIONAL ACADEMY PRESS Washington, D.C. 1991 Copyrightoriginal retained, the be not from cannot book, paper original however, for version formatting, author...

  14. A report from the American college of rheumatology/association of rheumatology health professionals (ACR/ARHP) - 2012 annual meeting (November 9-14, 2012 - Washington, D.C., USA).

    Science.gov (United States)

    Croasdell, G

    2013-02-01

    The annual meeting of the American College of Rheumatology (ACR), jointly held with the Association of Rheumatology Health Professionals (ARHP), brought together attendees focused on all aspects of rheumatology, including researchers looking into treatment options and various services around the care of rheumatologic conditions. As well as networking opportunities at the meeting, there were a wide range of symposia and posters available covering various conditions and levels of research. There were also educational and meet-the-professor sessions. This report will cover a selection of interesting talks from poster and oral sessions on the latest preclinical and clinical research. Copyright 2013 Prous Science, S.A.U. or its licensors. All rights reserved.

  15. 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...... of the second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or forcing substantially 0 degree phase shift, between corresponding resonant voltage waveforms of the first...

  16. 77 FR 21622 - Rehabilitation Research and Development Service Scientific Merit Review Board; Notice of Meeting

    Science.gov (United States)

    2012-04-10

    ... DEPARTMENT OF VETERANS AFFAIRS Rehabilitation Research and Development Service Scientific Merit...-463 (Federal Advisory Committee Act) that a meeting of the Rehabilitation Research and Development Service Scientific Merit Review Board will be held on April 20, 2012, 131 M Street NE., Washington, DC...

  17. Program and Abstracts of the National Meeting of the Society for Leukocyte Biology (25th) Held in Washington, DC on October 27-30, 1988. Journal of Leukocyte Biology. Volume 44, Number 4

    Science.gov (United States)

    1988-10-01

    Servicio de Inmunologia, Univ. Autonoma. Hospital de Ia Princesa. c/Diego de Leon, 62- 28006 Madrid, Spain. 5:15 PM 68. PROTEIN KINASE C ISOTYPE...Montreal General Hospital Research Insti- Ladner. G. Martin and S. Haskill, Depts. of tute, Montreal, Canada H3G 1A4 and *Department of Micro . and...Botet and M.O. de University and UMDNJ-Robert Wood Johnson Landazuri. Servicio de Inmunologia. Univ. Autonoma. Medical School, Piscataway, NJ 08854

  18. 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.

  19. A model for incorporating patient and stakeholder voices in a learning health care network: Washington State's Comparative Effectiveness Research Translation Network.

    Science.gov (United States)

    Devine, Emily Beth; Alfonso-Cristancho, Rafael; Devlin, Allison; Edwards, Todd C; Farrokhi, Ellen T; Kessler, Larry; Lavallee, Danielle C; Patrick, Donald L; Sullivan, Sean D; Tarczy-Hornoch, Peter; Yanez, N David; Flum, David R

    2013-08-01

    To describe the inaugural comparative effectiveness research (CER) cohort study of Washington State's Comparative Effectiveness Research Translation Network (CERTAIN), which compares invasive with noninvasive treatments for peripheral artery disease, and to focus on the patient centeredness of this cohort study by describing it within the context of a newly published conceptual framework for patient-centered outcomes research (PCOR). The peripheral artery disease study was selected because of clinician-identified uncertainty in treatment selection and differences in desired outcomes between patients and clinicians. Patient centeredness is achieved through the "Patient Voices Project," a CERTAIN initiative through which patient-reported outcome (PRO) instruments are administered for research and clinical purposes, and a study-specific patient advisory group where patients are meaningfully engaged throughout the life cycle of the study. A clinician-led research advisory panel follows in parallel. Primary outcomes are PRO instruments that measure function, health-related quality of life, and symptoms, the latter developed with input from the patients. Input from the patient advisory group led to revised retention procedures, which now focus on short-term (3-6 months) follow-up. The research advisory panel is piloting a point-of-care, patient assessment checklist, thereby returning study results to practice. The cohort study is aligned with the tenets of one of the new conceptual frameworks for conducting PCOR. The CERTAIN's inaugural cohort study may serve as a useful model for conducting PCOR and creating a learning health care network. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. 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.

  1. 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.

  2. An annotated checklist of the vascular flora of Washington County Mississippi

    Science.gov (United States)

    Field explorations have yielded 257 species new to Washington County, Mississippi and Calandrinia ciliata (Ruiz & Pav.) DC. and Ruellia nudiflora (Engelm. & Gray) Urban new to the state. An annotated list of 796 taxa for Washington County is provided and excludes 62 species that were reported from ...

  3. Research-informed strategies to address educational challenges in a digitally networked world: the EDUsummIT 2013 action agenda

    NARCIS (Netherlands)

    Voogt, J.; Knezek, G.; Searson, M.; Lai, K.W.; Gibson, D.; Khaddage, F.; Mishra, P.; Laferriere, T.; Resta, P.; Fisser, P.; Albion, P.; Searson, M.; Ochoa, M.

    2014-01-01

    EduSummIT is a global community of policy-makers, researchers, and educators working together to move education into the digital age. EDUsummIT 2013 took place in Washington DC and resulted in an action agenda for researchers, policy makers and educators to take concrete steps to move education in

  4. A resonant dc-dc power converter assembly

    OpenAIRE

    Madsen, Mickey Pierre

    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 second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or fo...

  5. NSA Diana Wueger Published in Washington Quarterly

    OpenAIRE

    Grant, Catherine L.

    2016-01-01

    National Security Affairs (NSA) News NSA Faculty Associate for Research Diana Wueger has recently had an article titled “India’s Nuclear-Armed Submarines: Deterrence or Danger?” published in the Washington Quarterly.

  6. Naval Air Systems Command-Naval Research Laboratory Workshop on Basic Research Needs for Synthetic Hydrocarbon Jet Aircraft Fuels Held at Naval Research Laboratory, Washington, DC on June 15 and 16, 1978

    Science.gov (United States)

    1978-01-01

    HXN HNN PXtX XTHDCPD Rrgw 1. Strwuture of compouns ..,Aed in the present paper: hexacyclic exo,exo.dihydrodlnorbornadlene (HXX), hexacyclic en,dow,’d...10 NN .. XTHDCPD 10 $Jlwo1 Artwkja plos of ~ Wxmft vsof1~ HIM wt4 dXThOCPD Sol hewe eulca*d Wkm leat.e VOft eqaUow I s 1n Fig. 3 are shown viscosity...simple relations such as EXini (additive viscosities), /EXi/rli (additive 212 HNN - XTHDCPD 10 -40*C 010 500 0001 000.2 0.4 0.5 0e.8 XXTHDCPD Fiq

  7. Clinostats and centrifuges: Their use, value, and limitations in gravitational biological research; Symposium, Washington, Oct. 19, 1991, Report

    Science.gov (United States)

    Halstead, Thora W. (Editor); Todd, Paul (Editor); Powers, Janet V. (Editor)

    1992-01-01

    The present volume addresses physical phenomena and effects associated with clinostat and centrifuge operations as well as their physiological effects. Particular attention is given to the simulation of the gravity conditions on the ground, the internal dynamics of slowly rotating biological systems, and qualitative and quantitative aspects of the fast-rotating clinostat as a research tool. Also discussed are the development and use of centrifuges in gravitational biology, the use of centrifuges in plant gravitational biology and a comparison of ground-based and flight experiment results, the ability of clinostat to mimic the effect of microgravity on plant cells and organs, and the impact of altered gravity conditions on early EGF-induced signal transduction in human epidermal A431 cells.

  8. 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.

  9. 76 FR 52566 - Drawbridge Operation Regulations; Anacostia River, Washington, DC

    Science.gov (United States)

    2011-08-23

    ...- 6629, e-mail [email protected] . If you have questions on viewing or submitting material to... material received during the comment period and may change the rule based on your comments. Viewing... in August 2004 and allows the bridge to be operated from a remote location, the Benning Yard office...

  10. 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.

  11. 147 between the holocaust museum in washington dc and ghana's

    African Journals Online (AJOL)

    HP-G61

    opens up a whole debate surrounding race, “horrors of the middle passage, the brutality of ... interesting that African Americans make strong genealogical bonds with the site as a ... mentioned parties were involved in the conflicting perspectives that laid .... However, some white Americans have propagated a message not in.

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

    International Nuclear Information System (INIS)

    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 ampersand 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 ampersand H awareness at all staff levels and in identifying ES ampersand 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 ampersand 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 ampersand H program. 4 figs., 24 tabs

  13. 77 FR 25781 - Environmental Impact Statement; Washington, DC

    Science.gov (United States)

    2012-05-01

    ... DEPARTMENT OF TRANSPORTATION Federal Highway Administration Environmental Impact Statement... Columbia, Department of Transportation. ACTION: Notice of Intent to Prepare a Draft Environmental Impact... agencies and the public that a Draft Environmental Impact Statement (DEIS) will be prepared to assess the...

  14. 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…

  15. 2013 Building America Research Planning Meeting Summary

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Cheryn E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hunt, Stacy [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    The Building America (BA) Research Planning Meeting was held October 28-30, 2013, in Washington, DC. This meeting provides one opportunity each year for the research teams, national laboratories and Department of Energy (DOE) managers to meet in person to share the most pertinent information and collaboration updates. This report documents the presentations, highlights key program updates, and outlines next steps for the program.

  16. 77 FR 42297 - Meeting of the Ocean Research and Resources Advisory Panel

    Science.gov (United States)

    2012-07-18

    ... Consortium for Ocean Leadership, 1201 New York Avenue NW., 4th Floor, Washington, DC 2005. FOR FURTHER... discussions on ocean research, resource management, and other current issues in the ocean science and management communities. J.M. Beal, Lieutenant Commander, Office of the Judge Advocate General, U.S. Navy...

  17. Proceedings of the 10th ASIS SIG/CR classification research workshop

    DEFF Research Database (Denmark)

    This volume is a working copy of the papers presented at the 9th ASIS SIG/CR workshop on classification research, held in Washington, DC, at the ASIS Annual Meeting on Sunday 31 October 1999. The contributions printed here are working papers, and thus, not necessarily in their final form...

  18. DOE-Supported Researcher Is Co-Winner of 2006 Nobel Prize in Physics

    Science.gov (United States)

    DOE-Supported Researcher Is Co-Winner of 2006 Nobel Prize in Physics October 3, 2006 WASHINGTON, DC Space Flight Center for co-winning the 2006 Nobel Prize in Physics. "I offer my congratulations to with the 2006 Nobel Prize in Physics," Secretary Bodman said. "The groundbreaking work of

  19. Hierarchical Control for Multiple DC-Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Vasquez, Juan Carlos

    2014-01-01

    DC microgrids (MGs) have gained research interest during the recent years because of many potential advantages as compared to the ac system. To ensure reliable operation of a low-voltage dc MG as well as its intelligent operation with the other DC MGs, a hierarchical control is proposed in this p......DC microgrids (MGs) have gained research interest during the recent years because of many potential advantages as compared to the ac system. To ensure reliable operation of a low-voltage dc MG as well as its intelligent operation with the other DC MGs, a hierarchical control is proposed...

  20. Full range ZVS DC-DC converter

    International Nuclear Information System (INIS)

    Upadhyay, Rinki; Badapanda, M.K.; Hannurkar, P.R.

    2011-01-01

    A 500 V, 24 Amp DC-DC converter with digital signal processor (DSP) based control and protection has been designed, fabricated and tested. Its power circuit consists of IGBT based single phase inverter bridge, ferrite transformer and diode rectifier. All IGBTs in the inverter bridge are operated in zero voltage switching (ZVS) mode to minimize switching losses thereby increasing the efficiency of the converter significantly. The efficiency of this converter is measured to be greater than 97% at full load. In a conventional full bridge inverter, typically ZVS is achieved under full load condition while at light load ZVS is lost. An auxiliary LC circuit has been intentionally incorporated in this converter to achieve ZVS even at light loaded conditions. Detailed simulation of the converter circuit is carried out and crucial waveforms have been presented in this paper. Microchip make dsPIC30F2020 DSP is employed to provide phase shifted PWMs to IGBTs in the inverter bridge. All the crucial parameters are also monitored by this DSP and in case of any unfavorable conditions, the converter is tripped off. Suitable experiments were carried out in this DC-DC converter under different loaded conditions and a close match between the simulated and experimental results were obtained. Such DC-DC converters can be connected in series or parallel for the development of solid state modular power supplies for various applications. (author)

  1. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: recommendations of the International RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group†.

    Science.gov (United States)

    Schiffman, Eric; Ohrbach, Richard; Truelove, Edmond; Look, John; Anderson, Gary; Goulet, Jean-Paul; List, Thomas; Svensson, Peter; Gonzalez, Yoly; Lobbezoo, Frank; Michelotti, Ambra; Brooks, Sharon L; Ceusters, Werner; Drangsholt, Mark; Ettlin, Dominik; Gaul, Charly; Goldberg, Louis J; Haythornthwaite, Jennifer A; Hollender, Lars; Jensen, Rigmor; John, Mike T; De Laat, Antoon; de Leeuw, Reny; Maixner, William; van der Meulen, Marylee; Murray, Greg M; Nixdorf, Donald R; Palla, Sandro; Petersson, Arne; Pionchon, Paul; Smith, Barry; Visscher, Corine M; Zakrzewska, Joanna; Dworkin, Samuel F

    2014-01-01

    The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥ 0.95. Consequently, these empirical results supported the development of revised RDC/TMD Axis I diagnostic algorithms that were subsequently demonstrated to be valid for the most common pain-related TMD and for one temporomandibular joint (TMJ) intra-articular disorder. The original RDC/TMD Axis II instruments were shown to be both reliable and valid. Working from these findings and revisions, two international consensus workshops were convened, from which recommendations were obtained for the finalization of new Axis I diagnostic algorithms and new Axis II instruments. Through a series of workshops and symposia, a panel of clinical and basic science pain experts modified the revised RDC/TMD Axis I algorithms by using comprehensive searches of published TMD diagnostic literature followed by review and consensus via a formal structured process. The panel's recommendations for further revision of the Axis I diagnostic algorithms were assessed for validity by using the Validation Project's data set, and for reliability by using newly collected data from the ongoing TMJ Impact Project-the follow-up study to the Validation Project. New Axis II instruments were identified through a comprehensive search of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting any pain-related TMD as well as valid diagnostic criteria for differentiating the most common pain-related TMD (sensitivity ≥ 0.86, specificity ≥ 0.98) and for one intra

  2. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: Recommendations of the International RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group†

    Science.gov (United States)

    Schiffman, Eric; Ohrbach, Richard; Truelove, Edmond; Look, John; Anderson, Gary; Goulet, Jean-Paul; List, Thomas; Svensson, Peter; Gonzalez, Yoly; Lobbezoo, Frank; Michelotti, Ambra; Brooks, Sharon L.; Ceusters, Werner; Drangsholt, Mark; Ettlin, Dominik; Gaul, Charly; Goldberg, Louis J.; Haythornthwaite, Jennifer A.; Hollender, Lars; Jensen, Rigmor; John, Mike T.; De Laat, Antoon; de Leeuw, Reny; Maixner, William; van der Meulen, Marylee; Murray, Greg M.; Nixdorf, Donald R.; Palla, Sandro; Petersson, Arne; Pionchon, Paul; Smith, Barry; Visscher, Corine M.; Zakrzewska, Joanna; Dworkin, Samuel F.

    2015-01-01

    Aims The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥ 0.95. Consequently, these empirical results supported the development of revised RDC/TMD Axis I diagnostic algorithms that were subsequently demonstrated to be valid for the most common pain-related TMD and for one temporomandibular joint (TMJ) intra-articular disorder. The original RDC/TMD Axis II instruments were shown to be both reliable and valid. Working from these findings and revisions, two international consensus workshops were convened, from which recommendations were obtained for the finalization of new Axis I diagnostic algorithms and new Axis II instruments. Methods Through a series of workshops and symposia, a panel of clinical and basic science pain experts modified the revised RDC/TMD Axis I algorithms by using comprehensive searches of published TMD diagnostic literature followed by review and consensus via a formal structured process. The panel's recommendations for further revision of the Axis I diagnostic algorithms were assessed for validity by using the Validation Project's data set, and for reliability by using newly collected data from the ongoing TMJ Impact Project—the follow-up study to the Validation Project. New Axis II instruments were identified through a comprehensive search of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. Results The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting any pain-related TMD as well as valid diagnostic criteria for differentiating the most common pain-related TMD (sensitivity ≥ 0.86, specificity ≥ 0

  3. Researches on the Improvement of the Bioactivity of TiO2 Deposits, Obtained by Magnetron Sputtering - DC

    Science.gov (United States)

    Toma, B. F.; Baciu, R. E.; Bejinariu, C.; Cimpoieşu, N.; Ciuntu, B. M.; Toma, S. L.; Burduhos-Nergis, D. P.; Timofte, D.

    2018-06-01

    In this paper, layers of TiO2 were deposited, by magnetron sputtering, on a glass support. The parameters of the deposition process were kept constant except for the O2/(Ar + O2) ratio that varied on three levels. The physical and mechanical properties of the layers obtained were investigated by SEM optical microscopy, electronics, AFM and X-ray diffraction. The bioactivity of TiO2 surfaces was investigated by growing M3C3-E1 osteoblast cells produced by RIKEN Cell Bank (Japan) for a period of 5 days. The modification of the working environment in the enclosure determines both the phasic modification in the TiO2 film, respectively the amount of the anatase or rutile phase and the decrease of the average roughness of the film from 112.3nm to 56.7nm. The research has demonstrated that the finer layers with a high content of anatase promote the growth of M3C3-E1 cells.

  4. Distributed Control for Paralleled PWM Inverters in the DC Zonal Distribution System

    National Research Council Canada - National Science Library

    Marinac, Mark

    1999-01-01

    .... The advantages of DC ZEDS will be exploited in the next class of surface combatants. Part of the development research for DC ZEDS includes the design of autonomous DC-to-AC inverter modules having robust load sharing capability...

  5. 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.

  6. Modeling and simulation for micro DC motor based on simulink

    Science.gov (United States)

    Shen, Hanxin; Lei, Qiao; Chen, Wenxiang

    2017-09-01

    The micro DC motor has a large market demand but there is a lack of theoretical research for it. Through detailed analysis of the commutation process of micro DC motor commutator, based on micro DC motor electromagnetic torque equation and mechanical torque equation, with the help of Simulink toolkit, a triangle connection micro DC motor simulation model is established. By using the model, a sample micro DC motor are simulated, and an experimental measurements has been carried on the sample micro DC motor. It is found that the simulation results are consistent with theoretical analysis and experimental results.

  7. High voltage dc cables

    Energy Technology Data Exchange (ETDEWEB)

    Bjustrom, B

    1965-12-01

    How stress distribution in dc cables varies with temperature and stress level, influence of polarity reversals and space charges, and different types of overvoltage to which dc cable may be subjected are discussed. Design problems, especially as related to corrosion protection and to mechanical stress caused by wire armoring during manufacturing and laying, accessories and work done on test methods, and the possibility of designing 400 to 600 kV dc cables for transmitting 2000 to 4000 MW are described.

  8. Congress in Washington

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Full text: Over 1200 accelerator physicists and engineers gathered in Washington mid-May for the 15th in the series of biennial Particle Accelerator Conferences (PAC) - the major US forum for accelerator physics and technology. For the first time since their inception, actual attendance declined, however the number of contributed papers stayed around 1500. CERN Director General designate Chris Llewellyn Smith spelled out the challenges with an opening talk underlining the deficiencies in today's Standard Model. From many directions comes the message that collision in the 1 TeV range must tell us something new - wherefore art thou SSC and LHC? The secondary shock waves of last year's (fortunately overturned) bid to cancel the SSC Superconducting Supercollider project still ripple around the USA, while progress towards authorization of CERN's LHC Large Hadron Collider has been slower than initially hoped. The new US administration has indicated a constant rate of SSC funding over the next four years; the figure is higher than the present budget but considerably below the originally proposed budget profile, implying that completion will be retarded by some three years beyond the end of the decade. The SSC Laboratory will clearly have problems to fight increased overall cost and sustain enthusiasm. CERN hopes for LHC blessing in time to allow machine completion by the year 2000. Pride of place at Washington went to DESY's HERA electron-proton collider - the major new facility since the previous PAC. Commissioning has been impressive and physics is well underway, with luminosity climbing towards the design figure. The varied user community of the ubiquitous synchrotron radiation facilities is now considerably larger than that of particle physics and has extensive industrial involvement. Three such machines have come into operation since the previous PAC - the 6 GeV European Synchrotron Radiation Facility at Grenoble, the 1.5 GeV Advanced Light Source

  9. 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

  10. 75 FR 28757 - Security Zone; Potomac River, Washington Channel, Washington, DC

    Science.gov (United States)

    2010-05-24

    ... potential terrorist acts, and enhance public and maritime safety and security. The Coast Guard was unable to...-ranking government officials, mitigating potential terrorist acts and enhancing public and maritime safety... terrorist acts and enhancing public and maritime safety and security. Basis and Purpose The Coast Guard will...

  11. The 1996 IDA Cost Research Symposium.

    Science.gov (United States)

    1996-08-01

    5160 Christopher Deegan (703)602-6575 Performer: Naval Surface Warfare Center (211) Carderock Division, NSWC/CD Bethesda, Maryland 20084-5000...Moore (703) 602-0330, ext 208 Cost Engineering Research, Inc. 2011 Crystal Drive Arlington, VA 22202-3717 Bill Hugo Bob Craig Classification...Director, Force and Infrastructure Cost Analysis Division OD (PA&E) Room 2D278, The Pentagon Washington, DC 20301 Dr. Craig College LMI John Wallace

  12. Family of multiport bidirectional DC-DC converters

    NARCIS (Netherlands)

    Tao, H.; Kotsopoulos, A.; Duarte, J.L.; Hendrix, M.A.M.

    2006-01-01

    Multiport DC-DC converters are of potential interest in applications such as generation systems utilising multiple sustainable energy sources. A family of multiport bidirectional DC-DC converters derived from a general topology is presented. The topology shows a combination of DC-link and magnetic

  13. 75 FR 33736 - Tart Cherries Grown in the States of Michigan, New York, Pennsylvania, Oregon, Utah, Washington...

    Science.gov (United States)

    2010-06-15

    ...., Stop 0237, Washington, DC 20250-0237; telephone: (202) 720-2491, Fax: (202) 720-8938, or E-mail: Laurel... DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 930 [Doc. No. AO-370-A8; AMS..., Oregon, Utah, Washington, and Wisconsin; Withdrawal of Proposed Rule AGENCY: Agricultural Marketing...

  14. Programmable dc motor controller

    Science.gov (United States)

    Hopwood, J. E.

    1982-11-01

    A portable programmable dc motor controller, with features not available on commercial instruments was developed for controlling fixtures during welding processes. The controller can be used to drive any dc motor having tachometer feedback and motor requirements not exceeding 30 volts, 3 amperes. Among the controller's features are delayed start time, upslope time, speed, and downslope time.

  15. Multilevel DC link inverter

    Science.gov (United States)

    Su, Gui-Jia

    2003-06-10

    A multilevel DC link inverter and method for improving torque response and current regulation in permanent magnet motors and switched reluctance motors having a low inductance includes a plurality of voltage controlled cells connected in series for applying a resulting dc voltage comprised of one or more incremental dc voltages. The cells are provided with switches for increasing the resulting applied dc voltage as speed and back EMF increase, while limiting the voltage that is applied to the commutation switches to perform PWM or dc voltage stepping functions, so as to limit current ripple in the stator windings below an acceptable level, typically 5%. Several embodiments are disclosed including inverters using IGBT's, inverters using thyristors. All of the inverters are operable in both motoring and regenerating modes.

  16. Floating high step-down stacked dc-dc converter based on buck-boost cells

    NARCIS (Netherlands)

    Tibola, G.; Duarte, J.L.; Blinov, A.

    2015-01-01

    In some high power dc-dc applications, where high voltage is present, a converter with high step-down ratio is required in order to provide an isolated low power auxiliary supply. This requirement represents a challenge and many topologies are currently being researched. The analysis of a

  17. Bidirectional dc-to-dc Power Converter

    Science.gov (United States)

    Griesbach, C. R.

    1986-01-01

    Solid-state, series-resonant converter uses high-voltage thyristors. Converter used either to convert high-voltage, low-current dc power to lowvoltage, high current power or reverse. Taking advantage of newly-available high-voltage thyristors to provide better reliability and efficiency than traditional converters that use vacuum tubes as power switches. New converter essentially maintenance free and provides greatly increased mean time between failures. Attractive in industrial applications whether or not bidirectional capability is required.

  18. Optical Computing Research.

    Science.gov (United States)

    1987-10-30

    1489-1496, 1985. 13. W.T. Welford and R. Winston, The Optics of Nonimaging Concentrators, Academic Press, New York, N.Y., 1978 (see Appendix A). 14. R.H...AD-fIB? Ŗ OPTICAL CONPIITINO RESEAIRCII(U STANFORD UlNIV CA STINFORD / ELECTRONICS LASS J N 0000W4 30 OCT 97 SMAFOSR-TR-S?-1635 RFOSR-96...Force Base ELEMENT NO. NO. NO. NO. Washington, DC 20332-6448 11. TITLE ,Include Security ClaaticaonUNCLASSIFIED 61102F 2305 B4 OPTICAL COMPUTING RESEARCH

  19. A DC Transformer

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the project was to demonstrate a true direct current (DC) transformer, a new electro-mechanical component with potentially high power applications; in...

  20. 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.

  1. Educator Supply and Demand in Washington State. 2004 Report

    Science.gov (United States)

    Lashway, Larry; Maloney, Rick; Hathaway, Randy; Bryant, B. J.

    2005-01-01

    This report describes the findings of the third Educator Supply and Demand Research study in the State of Washington. The intent of these Washington studies is to provide data to inform and shape decisions and activities in the following ways: (1) Provide useful information for educational policymakers, including the legislature, the State Board…

  2. Guest Editorial Special Issue on Structured DC Microgrids

    DEFF Research Database (Denmark)

    Guerrero, Josep M.; Tan, Don F. D.

    2017-01-01

    With the development of dc coupled devices, such as photovoltaic generations, batteries, supercapacitors, LEDs, computers, and electronics equipment, low-voltage dc distribution networks, structured dc microgrids are emerging as a natural platform to integrate renewable energy sources. However...... in either series/parallel, forming a number of dc busses with different voltage levels. Recently, with the advance of new dc power technologies, several ongoing standards, alliances, and initiatives are bringing the possibility of developing future homes, offices, buildings, campuses, datacenters, ships......, satellites, aircrafts, and other electrical power systems to operate totally or dominantly in dc. Research is being carried out in both the system and component levels of modeling, control, and stability of structured dc microgrids. New high-efficiency topologies and protections are also key nontrivial...

  3. 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...

  4. 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

    ... Airworthiness Directives; McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10... amends Sec. 39.13 by adding the following new AD: 2010-09-12 McDonnell Douglas Corporation: Amendment 39... to McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A...

  5. Design and Testing of Boost Type DC/DC Converter for DC Motor Control Applications

    OpenAIRE

    Samman, Faizal Arya; Akil, Yusri Syam; Noor, Nirwan A.

    2017-01-01

    in The Proceeding of The 2nd International Symposium on Smart Material and Mechatronics 2015 This paper presents the design and testing of a boost type DC/DC converter circuit, which can be used for DC motor control applications. The Boost converter is designed using DC chopper and DC chopper cascade configurations. The experimental setup was made by connecting the boost converter circuit with four types of DC motor, i.e. self-excited DC motor shunt, series, compound and separately exci...

  6. Control of improved full-bridge three-level DC/DC converter for wind turbines in a DC grid

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe

    2013-01-01

    transformer in the IFBTL dc/dc converter. A modulation strategy, including two operation modes, is proposed for the IFBTL dc/dc converter. Then, a voltage balancing control strategy is proposed for the IFBTL dc/dc converter. Furthermore, the control of the wind turbine based on the IFBTL dc/dc converter......This paper presents an improved full-bridge three-level (IFBTL) dc/dc converter for a wind turbine in a dc grid by inserting a passive filter into the dc/dc converter to improve the performance of the converter. The passive filter can effectively reduce the voltage stress of the medium frequency...

  7. 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

    on the rail system, and recommended improvements to improve the safety of the Metrorail system. These three influences show a holistic view of the...due to special events in the area to include Washington Redskins football , Washington National baseball, and other events held in the Washington, D.C...Station in Washington, DC. The accident resulted in nine people including the train operator were killed. Emergency response agencies reported

  8. Priority research areas to accelerate the development of practical ultraconductive copper conductors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dominic F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burwell, Malcolm [International Copper Association, Washington, DC (United States); Stillman, H. [International Copper Association, Washington, DC (United States)

    2015-09-01

    This report documents the findings at an Ultraconductive Copper Strategy Meeting held on March 11, 2015 in Washington DC. The aim of this meeting was to bring together researchers of ultraconductive copper in the U.S. to identify and prioritize critical non-proprietary research activities that will enhance the understanding in the material and accelerate its development into practical conductors. Every effort has been made to ensure that the discussion and findings are accurately reported in this document.

  9. 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....

  10. Artificial neural network control of sab dc/dc converter

    International Nuclear Information System (INIS)

    Mahar, M.A.; Abro, M.R.; Larik, A.S.

    2009-01-01

    The latest development of power semiconductor devices enable the modern power electronic converters to withstand high voltage and high power applications. Power electronic converters are mostly periodic variable structure systems due to their switched operations. The main drawback of these converters is the generation of oscillations which are developed during the operation of the converters under nonlinear situations. To handle these nonlinearities, various researchers have proposed different control techniques. Power electronic designers are devoting in the further development of converter topologies and their control techniques. SAB (Single Active Bridge) DC/DC converter is a new topology recently introduced by Demetriades. This topology is used in high voltage and high power applications. Because of its smart features, SAB converter has recently drawn attention of many researchers. However, during the operation of SAB converter severe oscillations are generated. In this research work, a novel NNC (Neural Network Controller) model is developed for SAB converter to minimize oscillations generated during its operation. NNC is believed to be an advanced nonlinear and robust controller which has the ability to map the nonlinear behaviour in a negligible response time. The performance of SAB converter with NNC is tested under dynamic region by considering the reference voltage variation and duty ratio variation. The SAB converter is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)

  11. Research on the Inductance/Capacitance Switch Model for an LCC-HVDC Converter in an AC/DC Hybrid Grid

    Directory of Open Access Journals (Sweden)

    Yangyang He

    2018-03-01

    Full Text Available In order to improve the simulation speed of the AC/DC hybrid grid, the inductance/capacitance (L/C switch model for line-commutated converter of high-voltage direct current (LCC-HVDC is presented in this study. The time domain modeling method is used to analyze the circuit of L/C switch model for the six-pulse system in LCC-HVDC in a switching period. A parameter setting method of L/C switch model is proposed considering the transient response, the steady state performance, switching losses and simulation error of the switch. The inductance/capacitance (L/C switch model for LCC-HVDC has the advantage of keeping the admittance matrix unchanged regardless of the change of switching state, which improves the simulation efficiency. Finally, the validity of the parameter setting method is verified. Compared with the test results of PSCAD/EMTDC, the accuracy of the proposed LCC-HVDC simulation model is proved. The model is suitable for real-time or offline simulation of AC/DC hybrid grid.

  12. Multi Bus DC-DC Converter in Electric Hybrid Vehicles

    Science.gov (United States)

    Krithika, V.; Subramaniam, C.; Sridharan, R.; Geetha, A.

    2018-04-01

    This paper is cotncerned with the design, simulation and fabrication of the prototype of a Multi bus DC- DC converter operating from 42V DC and delivering 14V DC and 260V DC. As a result, three DC buses are interconnected through a single power electronic circuitry. Such a requirement is energized in the development of a hybrid electric automobile which uses the technology of fuel cell. This is implemented by using a Bidirectional DC-DC converter configuration which is ideally suitable for multiple outputs with mutual electrical isolation. For the sake of reduced size and cost of step-up transformer, selection of a high frequency switching cycle at 10 KHz was done.

  13. USING THE SEDIMENT QUALITY TRIAD (SQT) APPROACH TO ASSESS SEDIMENTARY CONTAMINATION IN THE ANACOSTIA RIVER, WASHINGTON

    Science.gov (United States)

    Using the Sediment Quality Triad (SQT) Approach to Assess Sedimentary Contamination in the Anacostia River, Washington, D.C. Velinsky, DJ*1, Ashley, JTF1,2, Pinkney, F.3, McGee, BL3 and Norberg-King, TJ.4 1Academy of Natural Sciences-PCER, Philadelphia, PA. 2Philadelphia Universi...

  14. Chi Ka Sha Goes to Washington: Chickasaw Narratives on the NMAI

    Science.gov (United States)

    Hinson, Joshua Don

    2005-01-01

    This narrative describes the author's visit to Washington DC to attend the opening of the National Museum of the American Indian (NMAI). As a member of the Chickasaw, the author pondered what he would find in the museum that would represent the Chickasaw Nation. Would the museum reflect his people in all their diversity? Would he see something of…

  15. 75 FR 12718 - United States Navy Restricted Area, Puget Sound, Naval Station Everett, Washington

    Science.gov (United States)

    2010-03-17

    ... . Follow the instructions for submitting comments. E-mail: david.b.olson@usace.army.mil . Include the..., Attn: CECW-CO (David B. Olson), 441 G Street, NW., Washington, DC 20314-1000. Hand Delivery/Courier... copy form. FOR FURTHER INFORMATION CONTACT: Mr. David Olson, Headquarters, Operations and Regulatory...

  16. 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.

  17. Employee Turnover and Absenteeism: A Future Research Agenda.

    Science.gov (United States)

    1981-08-01

    Department (NMPC-6) Washington, DC 20350 Naval Training Analysis and Evaluation Group Orlando, FL 32813 Commanding Officer ATTN: TIC , Bldg. 2068 Naval...RD-i Washington, DC 20380 Educacion Advisor Education Center (E031) MCDEC Quantico, VA 22134 Commanding Officer Education Center (E031) MCDZC Quantico

  18. Automatic speed management in The Netherlands. [Paper presented at the 75th Annual Meeting of the Transportation Research Board TRB, Washington, D.C., January 7-11, 1996.

    NARCIS (Netherlands)

    Oei, H.-l.

    1996-01-01

    Speed warning and enforcement can be applied locally, on a road-stretch and on a road-network. Local automatic speed warning at an urban intersection reduced the mean speed by 5 km/h. Theoretically a reduction in accidents of 25-65% can be achieved. At a rural intersection, the speed limit was

  19. Thyristors for dc transmission

    Energy Technology Data Exchange (ETDEWEB)

    1966-05-06

    As a first stage towards determining the feasibility of applying thyristors to hvdc converter terminals, the Westinghouse Electric Corporation has built a converter laboratory capable of testing thyristors under conditions similar to those which would have to be met in a 200 kV dc system. The equipment has been designed to test a 5 kV 600 A group of thyrisotrs, elevated 200 kV above earth. This rating has been chosen so that there would be a sufficient number of thyristors in series to enable the gating and voltage division characteristics to be investigated and at the same time the group could be operated at a potential equivalent to a complete 200 kV dc bridge.

  20. Comparison of solar panel cooling system by using dc brushless fan and dc water

    International Nuclear Information System (INIS)

    Irwan, Y M; Leow, W Z; Irwanto, M; M, Fareq; Hassan, S I S; Amelia, A R; Safwati, I

    2015-01-01

    The purpose of this article is to discuss comparison of solar panel cooling system by using DC brushless fan and DC water pump. Solar photovoltaic (PV) power generation is an interesting technique to reduce non-renewable energy consumption and as a renewable energy. The temperature of PV modules increases when it absorbs solar radiation, causing a decrease in efficiency. A solar cooling system is design, construct and experimentally researched within this work. To make an effort to cool the PV module, Direct Current (DC) brushless fan and DC water pump with inlet/outlet manifold are designed for constant air movement and water flow circulation at the back side and front side of PV module representatively. Temperature sensors were installed on the PV module to detect temperature of PV. PIC microcontroller was used to control the DC brushless fan and water pump for switch ON or OFF depend on the temperature of PV module automatically. The performance with and without cooling system are shown in this experiment. The PV module with DC water pump cooling system increase 3.52%, 36.27%, 38.98%in term of output voltage, output current, output power respectively. It decrease 6.36 °C compare than to PV module without DC water pump cooling system. While DC brushless fan cooling system increase 3.47%, 29.55%, 32.23%in term of output voltage, output current, and output power respectively. It decrease 6.1 °C compare than to PV module without DC brushless fan cooling system. The efficiency of PV module with cooling system was increasing compared to PV module without cooling system; this is because the ambient temperature dropped significantly. The higher efficiency of PV cell, the payback period of the system can be shorted and the lifespan of PV module can also be longer. (paper)

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

    OpenAIRE

    Liwen Pan; Chengning Zhang

    2016-01-01

    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 m...

  2. Opportunities for addressing laminated root rot caused by Phellinus sulphuracens in Washington's forests: A Report from the Washington State Academy of Sciences in cooperation with the Washington State Department of Natural Resources

    Science.gov (United States)

    R. James Cook; Robert L. Edmonds; Ned B. Klopfenstein; Willis Littke; Geral McDonald; Daniel Omdahl; Karen Ripley; Charles G. Shaw; Rona Sturrock; Paul Zambino

    2013-01-01

    This report from the Washington State Academy of Sciences (WSAS) is in response to a request from the Washington State Department of Natural Resources (DNR) to "identify approaches and opportunities ripe for research on understanding and managing root diseases of Douglas-fir." Similar to the process used by the National Research Council, the WSAS upon...

  3. Research and Development in Support of the Navy Technology Center for Safety and Survivability

    Science.gov (United States)

    1990-10-26

    Automotive Engineers. Inc. * Warrendale. PA (1984). (6) Zeelenberg . A. P.. FIJa ven Drat. HI. 3.. end Barker. H1. L.. Coor. Interastona Dlan Machines A...given by Zeelenberg et al.3. The CCAI is based on two simple in Table 1. The fuels were ranked in order of their measurements, namely viscosity and...authors thank R. N. Hazlett (Naval Research 3 Zeelenberg , A. P., Fijn van Draat, H. J. and Barker. H. L. ’Congres Laboratory, Washington, DC) for helpful

  4. 76 FR 59162 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-National Center...

    Science.gov (United States)

    2011-09-23

    .... Specifically, Anglicotech LLC, Washington, DC; Battelle, Columbus, OH; Baxter Healthcare Corporation, Round...; ARC Technology Solutions, LLC, Nashua, NH; BAE Systems, Wayne, NJ; BCT Technology, Inc., Keene, NH...

  5. Efficiency Analyses of a DC Residential Power Distribution System for the Modern Home

    Directory of Open Access Journals (Sweden)

    GELANI, H. E.

    2015-02-01

    Full Text Available The electric power system started as DC back in the nineteenth century. However, the DC paradigm was soon ousted by AC due to inability of DC to change its voltage level. Now, after many years, with the development of power electronic converters capable of stepping-up and down DC voltage and converting it to-and-from AC, DC appears to be challenging AC and attempting a comeback. We now have DC power generation by solar cells, fuel cells and wind farms, DC power transmission in the form of HVDC (High Voltage DC transmission, DC power utilization by various modern electronic loads and DC power distribution that maybe regarded as still in research phase. This paper is an attempt to investigate feasibility of DC in the distribution portion of electrical power system. Specifically, the efficiency of a DC distribution system for residential localities is determined while keeping in view the concept of daily load variation. The aim is to bring out a more practical value of system efficiency as the efficiencies of DC/DC converters making up the system vary with load variation. This paper presents the modeling and simulation of a DC distribution system and efficiency results for various scenarios are presented.

  6. On and off controlled resonant dc-dc power converter

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a resonant DC-DC power converter comprising an input side circuit comprising a positive and a negative input terminal for receipt of an input voltage or current and an output side circuit comprising positive and negative output terminals for supply of a converter...... output voltage and connection to a converter load. The resonant DC-DC power converter further comprises a rectification circuit connected between an output of a resonant network and the output side circuit. The resonant network is configured for alternatingly being charged from the input voltage...... or current and discharged through the rectification circuit by a first controllable switch arrangement in accordance with a first switch control signal. A second controllable switch arrangement of the resonant DC-DC power converter is configured to select a first impedance characteristic of the resonant...

  7. DC Cable for Railway

    Science.gov (United States)

    Tomita, Masaru

    The development of a superconducting cable for railways has commenced, assuming that a DC transmission cable will be used for electric trains. The cable has been fabricated based on the results of current testing of a superconducting wire, and various evaluation tests have been performed to determine the characteristics of the cable. A superconducting transmission cable having zero electrical resistance and suitable for railway use is expected to enhance regeneration efficiency, reduce power losses, achieve load leveling and integration of sub-stations, and reduce rail potential.

  8. Auxiliary resonant DC tank converter

    Science.gov (United States)

    Peng, Fang Z.

    2000-01-01

    An auxiliary resonant dc tank (ARDCT) converter is provided for achieving soft-switching in a power converter. An ARDCT circuit is coupled directly across a dc bus to the inverter to generate a resonant dc bus voltage, including upper and lower resonant capacitors connected in series as a resonant leg, first and second dc tank capacitors connected in series as a tank leg, and an auxiliary resonant circuit comprising a series combination of a resonant inductor and a pair of auxiliary switching devices. The ARDCT circuit further includes first clamping means for holding the resonant dc bus voltage to the dc tank voltage of the tank leg, and second clamping means for clamping the resonant dc bus voltage to zero during a resonant period. The ARDCT circuit resonantly brings the dc bus voltage to zero in order to provide a zero-voltage switching opportunity for the inverter, then quickly rebounds the dc bus voltage back to the dc tank voltage after the inverter changes state. The auxiliary switching devices are turned on and off under zero-current conditions. The ARDCT circuit only absorbs ripples of the inverter dc bus current, thus having less current stress. In addition, since the ARDCT circuit is coupled in parallel with the dc power supply and the inverter for merely assisting soft-switching of the inverter without participating in real dc power transmission and power conversion, malfunction and failure of the tank circuit will not affect the functional operation of the inverter; thus a highly reliable converter system is expected.

  9. Step-Up DC-DC Power Converter

    DEFF Research Database (Denmark)

    2015-01-01

    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...... 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...

  10. Cost-based droop scheme for DC microgrid

    DEFF Research Database (Denmark)

    Nutkani, Inam Ullah; Wang, Peng; Loh, Poh Chiang

    2014-01-01

    voltage level, less on optimized operation and control of generation sources. The latter theme is perused in this paper, where cost-based droop scheme is proposed for distributed generators (DGs) in DC microgrids. Unlike traditional proportional power sharing based droop scheme, the proposed scheme......-connected operation. Most importantly, the proposed scheme can reduce overall total generation cost in DC microgrids without centralized controller and communication links. The performance of the proposed scheme has been verified under different load conditions.......DC microgrids are gaining interest due to higher efficiencies of DC distribution compared with AC. The benefits of DC systems have been widely researched for data centers, IT facilities and residential applications. The research focus, however, has been more on system architecture and optimal...

  11. Reliability of capacitors for DC-link applications - An overview

    DEFF Research Database (Denmark)

    Wang, Huai; Blaabjerg, Frede

    2013-01-01

    DC-link capacitors are an important part in the majority of power electronic converters which contribute to cost, size and failure rate on a considerable scale. From capacitor users' viewpoint, this paper presents a review on the improvement of reliability of DC-link in power electronic converters...... from two aspects: 1) reliability-oriented DC-link design solutions; 2) conditioning monitoring of DC-link capacitors during operation. Failure mechanisms, failure modes and lifetime models of capacitors suitable for the applications are also discussed as a basis to understand the physics......-of-failure. This review serves to provide a clear picture of the state-of-the-art research in this area and to identify the corresponding challenges and future research directions for capacitors and their DC-link applications....

  12. Washington Accelerator Conference

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Highlights of the 1993 Particle Accelerator Conference, held in Washington in May, were picked out in the previous issue (page 18). Talks on the big hadron colliders reflected the sea-change in the accelerator world where the scale, complexity and cost of the front-line projects has slowed the pace of developments (not unlike the scene in particle physics itself). Speaking before the anti-SSC vote in the House of Representatives in June, Dick Briggs reviewed the situation at the SSC Superconducting Supercollider in Ellis County, Texas. The linac building is near completion and the Low Energy Booster will be ready to receive components early next year. Tunnelling for the Main Ring is advancing rapidly with four boring machines in action. Five miles of tunnel have been completed since January and the pace has now stepped up to nearly a mile each week. The superconducting magnet news is good. Following the successful initial string test of a half cell of the magnet lattice, a two-ring full cell with all associated services is being assembled. The mechanical robustness of the magnet design was confirmed when a dipole was taken to 9.7 T when cooled to 1.8 K. In the Magnet Test Lab itself, ten test stands are installed and equipped

  13. Recent developments: Washington focus

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Congress reconvened on January 23, but most of Washington's January new involves the Administration. DOE sent two letters to USEC customers, awarded a contract for the independent financial review of the enrichment program, and released a plan for demonstrating AVLIS by 1992. A General Accounting Office (GAO) report investigating the impact of imports of Soviet EUP into the US was made public. Both Congress and the administration are reportedly considering a full-scope US-Soviet Agreement for Nuclear Cooperation. Finally, published reports indicate Congress may consider ending the customs user fee which levies a charge of 0.17% on the value of all imported goods. The fee is felt to violate the General Agreement on Tariffs and Trade (GATT) and is not based on recovering actual Customs costs for processing a good. The fee brings the Treasury over $700 million per year, but the business community plans to lobby hard for its outright elimination or a change in authority to collect the fee based on actual costs

  14. Washington Accelerator Conference

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1993-09-15

    Highlights of the 1993 Particle Accelerator Conference, held in Washington in May, were picked out in the previous issue (page 18). Talks on the big hadron colliders reflected the sea-change in the accelerator world where the scale, complexity and cost of the front-line projects has slowed the pace of developments (not unlike the scene in particle physics itself). Speaking before the anti-SSC vote in the House of Representatives in June, Dick Briggs reviewed the situation at the SSC Superconducting Supercollider in Ellis County, Texas. The linac building is near completion and the Low Energy Booster will be ready to receive components early next year. Tunnelling for the Main Ring is advancing rapidly with four boring machines in action. Five miles of tunnel have been completed since January and the pace has now stepped up to nearly a mile each week. The superconducting magnet news is good. Following the successful initial string test of a half cell of the magnet lattice, a two-ring full cell with all associated services is being assembled. The mechanical robustness of the magnet design was confirmed when a dipole was taken to 9.7 T when cooled to 1.8 K. In the Magnet Test Lab itself, ten test stands are installed and equipped.

  15. Fuel management at Washington State Ferries

    International Nuclear Information System (INIS)

    Brodeur, P.; Olds, J.

    2008-01-01

    This presentation discussed Washington State Ferry (WSF) operations and provided details of a biodiesel research and demonstration project. Washington has the largest ferry system in the United States, with a total of 28 vessels that operate on 10 routes through 20 terminals. Routes vary by transit times, navigational challenges, and the proximity to population centres. WSF fuel and emissions management initiatives include exhaust emission studies, clean fuel initiatives, machinery upgrades, fuel conservation initiatives, and biodiesel testing. The organization is also using waste heat recovery and a positive restraint system. The WSF biodiesel pilot program was conducted using soy-derived fuels with a purifier disk stack. The program is in agreement with recent legislation requiring that 2 per cent of annual diesel fuel sales are from biodiesel fuels, and state legislation requiring that state agencies use a minimum of 20 per cent biodiesel blends in diesel-powered vessels and vehicles. Details of project partnerships were included. tabs., figs

  16. DC Distribution Systems and Microgrids

    DEFF Research Database (Denmark)

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

    2017-01-01

    summarized. Due to its attractive characteristics in terms of compliance with modern generation, storage and electronic load technologies, high reliability and current carrying capacity, as well as simple control, DC systems are already an indispensable part of power systems. Moreover, the existing......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...... challenges such as protection issues will be effectively resolved in the near future due to fast progress of semiconductor technology which is a key enabler cheap and reliable future DC solid-state protection systems. Therefore, it is the view of the author that more and more DC systems will appear...

  17. Research & development and growth: A Bayesian model averaging analysis

    Czech Academy of Sciences Publication Activity Database

    Horváth, Roman

    2011-01-01

    Roč. 28, č. 6 (2011), s. 2669-2673 ISSN 0264-9993. [Society for Non-linear Dynamics and Econometrics Annual Conferencen. Washington DC, 16.03.2011-18.03.2011] R&D Projects: GA ČR GA402/09/0965 Institutional research plan: CEZ:AV0Z10750506 Keywords : Research and development * Growth * Bayesian model averaging Subject RIV: AH - Economic s Impact factor: 0.701, year: 2011 http://library.utia.cas.cz/separaty/2011/E/horvath-research & development and growth a bayesian model averaging analysis.pdf

  18. 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...

  19. Current meter data from moored current meter casts in the Coastal Waters of Washington/Oregon as part of the Land-Margin Ecosystem Research (LEML) project, 06 May 1997 - 19 October 1997 (NODC Accession 9800193)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter data were collected using moored current meter casts in the Coastal Waters of Washington/Oregon from May 6, 1997 to October 19, 1997. Data were...

  20. 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...

  1. 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.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    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...

  3. 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.

  4. 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...

  5. 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 ca...

  6. 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.

  7. Historical changes to Lake Washington and route of the Lake Washington Ship Canal, King County, Washington

    Science.gov (United States)

    Chrzastowski, Michael J.

    1983-01-01

    Lake Washington, in the midst of the greater Seattle metropolitan area of the Puget Sound region (fig. 1), is an exceptional commercial, recreational, and esthetic resource for the region . In the past 130 years, Lake Washington has been changed from a " wild " lake in a wilderness setting to a regulated lake surrounded by a growing metropolis--a transformation that provides an unusual opportunity to study changes to a lake's shoreline and hydrologic characteristics -resulting from urbanization.

  8. University of Washington/ Northwest National Marine Renewable Energy Center Tidal Current Technology Test Protocol, Instrumentation, Design Code, and Oceanographic Modeling Collaboration: Cooperative Research and Development Final Report, CRADA Number CRD-11-452

    Energy Technology Data Exchange (ETDEWEB)

    Driscoll, Frederick R. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-11-01

    The University of Washington (UW) - Northwest National Marine Renewable Energy Center (UW-NNMREC) and the National Renewable Energy Laboratory (NREL) will collaborate to advance research and development (R&D) of Marine Hydrokinetic (MHK) renewable energy technology, specifically renewable energy captured from ocean tidal currents. UW-NNMREC is endeavoring to establish infrastructure, capabilities and tools to support in-water testing of marine energy technology. NREL is leveraging its experience and capabilities in field testing of wind systems to develop protocols and instrumentation to advance field testing of MHK systems. Under this work, UW-NNMREC and NREL will work together to develop a common instrumentation system and testing methodologies, standards and protocols. UW-NNMREC is also establishing simulation capabilities for MHK turbine and turbine arrays. NREL has extensive experience in wind turbine array modeling and is developing several computer based numerical simulation capabilities for MHK systems. Under this CRADA, UW-NNMREC and NREL will work together to augment single device and array modeling codes. As part of this effort UW NNMREC will also work with NREL to run simulations on NREL's high performance computer system.

  9. The performance of the DC motor by the PID controlling PWM DC-DC boost converter

    OpenAIRE

    Can, Erol; Sayan, Hasan Hüseyin

    2017-01-01

    This paper presents the PID controlling direct current (DC) to the direct current boost converter feds DC motor which has a 3.68 kW and 240 V of DC voltage input on its characteristics. What is first formed is the boost converter mathematical model at the design stage. Secondly, a mathematical model of the DC motor is created so that the boost converter with the machine can be established and modeled at the Matlab Simulink. The PID controller is considered for arranging a pulse width modulati...

  10. 75 FR 61989 - Airworthiness Directives; McDonnell Douglas Corporation Model DC-8-31, DC-8-32, DC-8-33, DC-8-41...

    Science.gov (United States)

    2010-10-07

    ... Airworthiness Directives; McDonnell Douglas Corporation Model DC- 8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, and... to all of the McDonnell Douglas Corporation airplanes identified above. The existing AD currently... the following new airworthiness directive (AD): 2010-21-03 McDonnell Douglas Corporation: Amendment 39...

  11. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for clinical and research applications: recommendations of the international RDC/TMD consortium network and orofacial pain special interest group

    NARCIS (Netherlands)

    Schiffman, E.; Ohrbach, R.; Truelove, E.; Look, J.; Anderson, G.; Goulet, J.P.; List, T.; Svensson, P.; Gonzalez, Y.; Lobbezoo, F.; Michelotti, A.; Brooks, S.L.; Ceusters, W.; Drangsholt, M.; Ettlin, D.; Gaul, C.; Goldberg, L.J.; Haythornthwaite, J.A.; Hollender, L.; Jensen, R.; John, M.T.; De Laat, A.; de Leeuw, R.; Maixner, W.; van der Meulen, M.; Murray, G.M.; Nixdorf, D.R.; Palla, S.; Petersson, A.; Pionchon, P.; Smith, B.; Visscher, C.M.; Zakrzewska, J.; Dworkin, S.F.

    2014-01-01

    AIMS: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥

  12. Integrating DC/DC Conversion with Possible Reconfiguration within Submodule Solar Photovoltaic Systems

    Science.gov (United States)

    Huang, Peter Jen-Hung

    This research first proposes a method to merge photovoltaic (PV) cells or PV panels within the internal components DC-DC converters. The purpose of this merged structure is to reconfigure the PV modules between series and parallel connections using high switching frequencies (hundreds of kHz). This leads to multi-levels of voltages and currents that become applied to the output filter of the converter. Further, this research introduces a concept of a switching cell that utilizes the reconfiguration of series and parallel connections in DC-DC converters. The switching occurs at high switching frequency and the switches can be integrated to be within the solar panels or in between the solar cells. The concept is generalized and applied to basic buck and boost topologies. As examples of the new types of converters: reconfigurable PV-buck and PV-boost converter topologies are presented. It is also possible to create other reconfigurable power converters: non-isolated and isolated topologies. Analysis, simulation and experimental verification for the reconfigurable PV-buck and PV-boost converters are presented extensively to illustrate proof of concept. Benefits and drawbacks of the new approach are discussed. The second part of this research proposes to utilize the internal solar cell capacitance and internal solar module wire parasitic inductances to replace the input capacitor and filter inductor in boost derived DC-DC converters for energy harvesting applications. High switching frequency (MHz) hard switched and resonant boost converters are proposed. Their analysis, simulation and experimental prototypes are presented. A specific proof-of-concept application is especially tested for foldable PV panels, which are known for their high internal wire inductance. The experimental converters successfully boost solar module voltage without adding any external input capacitance or filter inductor. Benefits and drawbacks of new proposed PV submodule integrated boost

  13. 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.

  14. Deadbeat control of power leveling unit with bidirectional buck/boost DC/DC converter

    OpenAIRE

    Hamasaki, Shin-ichi; Mukai, Ryosuke; Yano, Yoshihiro; Tsuji, Mineo

    2014-01-01

    As a distributed generation system increases, a stable power supply becomes difficult. Thus control of power leveling (PL) unit is required to maintain the balance of power flow for irregular power generation. The unit is required to respond to change of voltage and bidirectional power flow. So the bidirectional buck/boost DC/DC converter is applied for the control of PL unit in this research. The PL unit with Electric double-layer capacitor (EDLC) is able to absorb change of power, and it is...

  15. Design of interleaved multilayer rosen type piezoelectric transformer for high voltage dc/dc applications

    DEFF Research Database (Denmark)

    Rødgaard, Martin Schøler; Andersen, Thomas; Meyer, Kaspar Sinding

    2012-01-01

    Research and development within piezoelectric transformer (PT) based converters are rapidly increasing as the technology is maturing and starts to prove its capabilities. Especially for high voltage and high step-up applications, PT based converters have demonstrated good performance and DC...

  16. Next-Generation Shipboard DC Power System

    DEFF Research Database (Denmark)

    Jin, Zheming; Sulligoi, Giorgio; Cuzner, Rob

    2016-01-01

    sources (RES) are commonly recognized as the major driven force of the revolution, the outburst of customer electronics and new kinds of household electronics is also powering this change. In this context, dc power distribution technologies have made a comeback and keep gaining a commendable increase...... 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....... 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...

  17. 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.

  18. Oil spill response issues in Washington State

    International Nuclear Information System (INIS)

    Lempriere, P.R.

    1997-01-01

    Washington State statutes and regulations applicable to oil transport and oil spills were described. Specific provisions of the statutes and regulations and other relevant matters were also discussed. Among these were: (1) Washington State oil spill prevention plans, (2) Washington State oil spill contingency plans, (3) best achievable protection, (4) Intertanko's lawsuit against Washington State, (5) oil spill removal organizations, (6) certificates of financial responsibility in Washington State, (7) extent of potential liability under Washington Law, (8) disposal of cleanup materials, and (9) definition of 'qualified individuals' on marine vessels having the authority to implement removal actions

  19. 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...

  20. 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.

  1. 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.

  2. Linking DC together with TRSL

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Yong, X.

    2000-01-01

    in a method for real-time developments. An operational semantics with behavior is specified for TRSL. It is defined what its means for a TRSL process to satisfy a DC requirement, and a method for verifying whether the satisfaction relation holds or not is provided. Our contribution also demonstrates a general......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...

  3. DC Microgrids—Part II

    DEFF Research Database (Denmark)

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

    2016-01-01

    distribution applications such as traction, telecom, vehicular and distributed power systems can be classified under DC MG framework and ongoing development and expansion of the field is largely influenced by concepts used over there. This paper aims firstly to shed light on the practical design aspects of DC...... MG technology concerning typical power hardware topologies and their suitability for different emerging smart grid applications. Then, an overview of the state of the art in DC MG protection and grounding is provided. Owing to the fact that there is no zero current crossing, an arc that appears upon...

  4. 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.

  5. 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.

  6. 78 FR 52786 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Members Of SGIP 2...

    Science.gov (United States)

    2013-08-26

    ...., Houston, TX; The University of Tokyo, Bunkyo-ku, Tokyo, JAPAN; U.S. Department of Energy, Washington, DC... Computer Solutions, Herndon, VA; Tri-County Electric Cooperative, Inc., Hooker, OK; ARC Technical Resources... Group, Inc., Boston, MA; Alliance for Telecommunications Industry Solutions (ATIS), Washington, DC; and...

  7. What to Buy? The Role of Director of Defense Research and Engineering (DDR&E) Lessons from the 1970s

    Science.gov (United States)

    2011-01-01

    M. Thorndike , “Antisubmarine Warfare in World War II,” OEG Report No. 51 (Washington, DC: Operations Evaluation Group, 1946). The authors were not...Sternhell, Charles M. and Alan M. Thorndike . “Antisubmarine Warfare in World War II.” OEG Report No. 51. Washington, DC: Operations Evaluation Group

  8. 78 FR 9044 - Adequacy Status of the Motor Vehicle Emission Budgets for Metropolitan Washington DC Area (DC-MD...

    Science.gov (United States)

    2013-02-07

    ... Maryland Department of the Environment (MDE) and June 12, 2007 by both the Virginia Department of...-3335 or by email at: [email protected] . The finding is available at EPA's conformity Web site...-Hour Ozone Nonattainment Area submitted to EPA as a SIP revision on June 4, 2007 by MDE and June 12...

  9. Retrospective evaluation of early and aggressive decompressive craniectomy (DC) for severe head injury. Was that DC necessary?

    International Nuclear Information System (INIS)

    Hagihara, Yasushi; Ueno, Masato; Mizushima, Yasuaki; Matsuoka, Tetsuya

    2011-01-01

    Recently, decompressive craniectomy (DC) for refractory intracranial hypertension (IH) has been widely reevaluated, and many researchers support the advantages of early and aggressive DC in the management of severe head trauma. We too applied DC in the early stages of IH, and confirmed its favorable results compared to those of the standard treatment. In patients with evacuate masses (EM), DC was determined based on the intraoperative condition of the brain parenchyma; in those without EM, intracranial pressure (ICP) ≥30 mmHg was considered the criterion for DC. However, in some cases, the expected brain edema (BE) was absent after DC, and DC seemed unnecessary on retrospection. Here, the effectiveness of DC performed at our hospital and its predictive factors were investigated. Of the 26 DCs performed in the past 3.5 years, 9 were ineffective because the expected BEs were absent on postoperative computed tomography. In those 9 cases, the Glasgow coma scale (GCS) scores and D-dimer of fibrinogen degradation product (FDP-DD) were significantly higher and lower, respectively, than those of the control group. Patients with EM showed similar trends regarding the GCS score and FDP-DD, both of which are probable indicators of BE. In patients without EM, the GCS score and FDP-DD were normal, but their base excess at admission was significantly low with increased ICP, requiring DC. GCS score and FDP-DD may represent the extent of mechanically damaged brain, and this may explain their relation with DC effectiveness in patients with EM. In patients without EM and with mild brain damage, base excess that reflects the respiratory or circulatory disorder should be the predictor for BE. (author)

  10. Hearings Before the Select Committee on Nutrition and Human Needs of the United States Senate, Ninety-Second Congress, First Session on Nutrition and Human Needs. Part 10--Micronutrient Supplements for School Lunch Program. Hearings Held Washington, D.C., December 7, 1971.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Senate Select Committee on Nutrition and Human Needs.

    Contents of these hearings include the statement and testimony of the following witnesses: (1) Alan Young, Research Administrator, Research and Development Division, A. H. Robins Co.; Chairman, Board of Directors, Vitamin Information Bureau; (2) Dr. Joseph M. White, Nutritional and Medical Consultant, Miles Laboratories; (3) Dr. George Briggs,…

  11. Borehole DC-12 hydrostratigraphic chart

    International Nuclear Information System (INIS)

    Gephart, R.E.

    1981-09-01

    This hydrostratigraphic chart identifies the basic stratigraphy and preliminary hydrologic testing results for Borehole DC-12. This borehole was cored through the Saddle Mountains and Wanapum basalt formations and into the Grande Ronde. Selected zones were hydrologically tested during coring

  12. Borehole DC-14 hydrostratigraphic chart

    International Nuclear Information System (INIS)

    Gephart, R.E.

    1981-09-01

    This hydrostratigraphic chart identifies the basic stratigraphy and preliminary hydrologic testing results for Borehole DC-14. This borehole was cored through the Saddle Mountains and Wanapum basalt formations and into the Grande Ronde. Selected zones were hydrologically tested during coring

  13. Borehole DC-15 hydrostratigraphic chart

    International Nuclear Information System (INIS)

    Gephart, R.E.

    1981-09-01

    This hydrostratigraphic chart identifies the basic stratigraphy and preliminary hydrologic testing results for Borehole DC-15. This borehole was cored through the Saddle Mountains and Wanapum basalt formations and into the Grande Ronde. Selected zones were hydrologically tested during coring

  14. 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.

  15. 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.

  16. Light weight, high power, high voltage dc/dc converter technologies

    Science.gov (United States)

    Kraus, Robert; Myers, Ira; Baumann, Eric

    1990-01-01

    Power-conditioning weight reductions by orders of magnitude will be required to enable the megawatt-power-level space systems envisioned by the Strategic Defense Initiative, the Air Force, and NASA. An interagency program has been initiated to develop an 0.1-kg/kW dc/dc converter technology base for these future space applications. Three contractors are in the first phase of a competitive program to develop a megawatt dc/dc converter. Researchers at NASA Lewis Research Center are investigating innovative converter topology control. Three different converter subsystems based on square wave, resonant, and super-resonant topologies are being designed. The components required for the converter designs cover a wide array of technologies. Two different switches, one semiconductor and the other gas, are under development. Issues related to thermal management and material reliability for inductors, transformers, and capacitors are being investigated in order to maximize power density. A brief description of each of the concepts proposed to meet the goals of this program is presented.

  17. 78 FR 15053 - Simpson Lumber Company, LLC, Shelton, Washington; Simpson Lumber Company, LLC, Tacoma, Washington...

    Science.gov (United States)

    2013-03-08

    ...,372B] Simpson Lumber Company, LLC, Shelton, Washington; Simpson Lumber Company, LLC, Tacoma, Washington; Simpson Lumber Company, LLC, Longview, Washington; Notice of Revised Determination on Reconsideration On... Reconsideration for the workers and former workers of Simpson Lumber Company, LLC, Shelton, Washington (TA-W-81...

  18. Five-Level Active-Neutral-Point-Clamped DC/DC Converter for Medium-Voltage DC Grids

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Chen, Zhe

    2017-01-01

    This paper proposes a five-level active-neutralpoint- clamped (5L-ANPC) dc/dc converter for applications in medium voltage dc (MVDC) grids. A modulation strategy is proposed for the 5L-ANPC dc/dc converter to generate multilevel voltage waveforms, which can effectively reduce voltage change rate dv...... effectively eliminate high voltage leaps caused by the dead time effect. In addition, a capacitor voltage control strategy is proposed for the 5L-ANPC dc/dc converter to ensure the balanced flying capacitor voltage and desired five-level voltage waveforms. Finally, simulation and experimental studies...

  19. 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

    ... Airworthiness Directives; McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10... following new airworthiness directive (AD): 2010-21-13 McDonnell Douglas Corporation: Amendment 39-16473... November 18, 2010. Affected ADs (b) None. Applicability (c) This AD applies to McDonnell Douglas...

  20. 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

    ...-1044; Directorate Identifier 2010-NM-033-AD] RIN 2120-AA64 Airworthiness Directives; McDonnell Douglas..., 2007) and adding the following new AD: McDonnell Douglas Corporation: Docket No. FAA-2010-1044.... Applicability (c) This AD applies to all McDonnell Douglas Corporation Model DC-10-10, DC-10-10F, DC-10-15, DC...

  1. National Nutrition Policy Study--1974; Part 7-Nutrition and Government; and Part 7A-Appendix. Hearings Before the Select Committee on Nutrition and Human Needs of the United States Senate, Ninety-third Congress, Second Session. Hearings Held Washington, D.C., June 21, 1974.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Senate Select Committee on Nutrition and Human Needs.

    These hearings of the Senate Select Committee on Nutrition and Human Needs opened with a statement by Senator McGovern, chairman. The Panel on Nutrition and Government then delivered its report and recommendations to the committee. The panel was concerned with surveillance, research, the training of professional personnel, and the overall…

  2. Basic Design Report of DC-TOF Inelastic Neutron Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    So, Ji Yong; Park, Je Geun; Moon, Myung Kook; Cho, Sang Jin; Choi, Yung Hyun; Lee, Chang Hee

    2006-04-15

    We made Basic designs of neutron guide, choppers, and detectors in order to optimize the design parameters of DC-TOF to be built in the HANARO Cold Neutron Guide Hall. In addition, we calculated the expected performance of DC-TOF using Monte Carlo simulations and evaluated the properties of neutron beam. Based on the results we obtained, we have compared the expected performance of the DC-TOF with those of existing instruments overseas. In conclusion, we believe that we will be able to construct the DC-TOF at HANARO as one of the best instruments of its kinds and it will become an invaluable instrument to researchers in the related field.

  3. (Sw) DC (Leguminosae) pods

    African Journals Online (AJOL)

    International Pharmaceutical Abstract, Chemical Abstracts, Embase, Index Copernicus, EBSCO, African ... Since the discovery of terpenes, more than 150 years ago ... anticancer drug discovery. .... (Agricultural Research Service/USDA) [17].

  4. 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.

  5. Large-scale silviculture experiments of western Oregon and Washington.

    Science.gov (United States)

    Nathan J. Poage; Paul D. Anderson

    2007-01-01

    We review 12 large-scale silviculture experiments (LSSEs) in western Washington and Oregon with which the Pacific Northwest Research Station of the USDA Forest Service is substantially involved. We compiled and arrayed information about the LSSEs as a series of matrices in a relational database, which is included on the compact disc published with this report and...

  6. 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

    ... Airworthiness Directives; McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10... adding the following new AD: 2010-20-14 McDonnell Douglas Corporation: Amendment 39-16449. Docket No. FAA... the airplanes identified in paragraphs (c)(1) and (c)(2) of this AD. (1) McDonnell Douglas Corporation...

  7. 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

    ...-0032; Directorate Identifier 2009-NM-213-AD] RIN 2120-AA64 Airworthiness Directives; McDonnell Douglas...: McDonnell Douglas Corporation: Docket No. FAA-2010-0032; Directorate Identifier 2009-NM-213-AD. Comments Due... applies to McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-15, DC-10-30, DC-10-30F (KC-10A...

  8. 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

    ...-0672; Directorate Identifier 2010-NM-047-AD] RIN 2120-AA64 Airworthiness Directives; McDonnell Douglas...: McDonnell Douglas Corporation: Docket No. FAA-2010-0672; Directorate Identifier 2010-NM-047-AD. Comments Due... applies to McDonnell Douglas Corporation Model DC- 10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10...

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Druce, Robert L. (Union City, CA); Kirbie, Hugh C. (Dublin, CA); Newton, Mark A. (Livermore, CA)

    1998-01-01

    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.

  11. Radiated electromagnetic emissions of DC-DC converters

    International Nuclear Information System (INIS)

    Feld, L; Jussen, R; Karpinski, W; Klein, K; Sammet, J; Wlochal, M

    2010-01-01

    For the CMS tracker at SLHC a new powering scheme is considered to be mandatory to allow the detector to provide at least the same performance as today at the LHC. The baseline solution of CMS foresees the use of DC-DC converters to provide larger currents with smaller losses. An important component of most converters are inductors which, however, tend to radiate the switching noise generated by the converter. The emissions of different inductors have been measured and simulated, the coil design has been optimized and noise susceptibility measurements, with present CMS hardware, have been performed. This article summarizes the results.

  12. 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,

  13. DESIGN OPTIMIZATION OF RESONANT DC-DC CONVERTERS

    OpenAIRE

    Belqasem Aljafari

    2016-01-01

    Resonant DC/DC converters are the class of converters, which have L-C resonant tank serving as a major part of the power conversion process. The fundamental concept of the resonant converter is that the circulating energy in an L-C resonant circuit is manageable by changing the operating frequency, and therefore the converter can condition the input power to the desired output voltage. The development in power conversion technology is steady demand for high power efficiency and high power den...

  14. 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.

  15. Linking DC together with TRSL

    DEFF Research Database (Denmark)

    Haxthausen, Anne; Yong, Xia

    1999-01-01

    In this talk we present a method for linking the Duration Calculus together with the Timed RAISE Specification Language. Duration Calculus (DC) [ZHR91] is an interval-based real time logic, which can be used naturally in capturing and eliciting users' real time requirements in the form of constra......In this talk we present a method for linking the Duration Calculus together with the Timed RAISE Specification Language. Duration Calculus (DC) [ZHR91] is an interval-based real time logic, which can be used naturally in capturing and eliciting users' real time requirements in the form.......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...... 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...

  16. A Long-term View of Research Targets in Nanoelectronics

    International Nuclear Information System (INIS)

    Cavin, R. K.; Zhirnov, V. V.; Bourianoff, G. I.; Hutchby, J. A.; Herr, D. J. C.; Hosack, H. H.; Joyner, W. H.; Wooldridge, T. A.

    2005-01-01

    This paper presents a summary of the second workshop on Silicon Nanoelectronics and Beyond held at the National Science Foundation in Washington DC in December 2004. The objective was to set research directions to vigorously pursue both extending the CMOS technology to its limits and to develop Beyond-CMOS technologies to sustain the historical exponential improvement in performance/cost with time. Workshop themes were: (1) Post CMOS information processing technologies, (2) Novel materials and assembly methods for extending charge-based technology to its ultimate limits, (3) Multi-scale/multi-phenomena modeling and simulation, (4) Novel nano-architectures, and (5) Nano environmental safety and health

  17. 76 FR 8357 - Biological and Environmental Research Advisory Committee

    Science.gov (United States)

    2011-02-14

    ..., 2011, 9 a.m. to 12 p.m. ADDRESSES: Omni Shoreham Hotel, 2500 Calvert Street, NW., Washington, DC 20008... Response Joint Genome Institute Update and ARM review outbrief 2012 Budget briefing New Business Public...

  18. Aircraft Accident Report; Uncontrolled Impact with Terrain, Fine Airlines Flight 101, Douglas DC-8-61, N27UA, Miami, Florida, August 7, 1997

    Science.gov (United States)

    1998-06-16

    Transcolombiana de Carga ATI Air Transport International ATOS Air Transportation Oversight System ATP airline transport pilot CAM cockpit area microphone...495,000 fine against Aero Transcolombiana de Carga (ATC) for operating a DC-8-51 "over the weight limits set forth in its FAA-approved flight manual...PB98-910402 NTSB/AAR-98/02 DCA97MA059 NATIONAL TRANSPORTATION SAFETY BOARD WASHINGTON, D.C. 20594 AIRCRAFT ACCIDENT REPORT c>C== UNCONTROLLED IMPACT

  19. Lifetime Estimation of DC-link Capacitors in a Single-phase Converter with an Integrated Active Power Decoupling Module

    DEFF Research Database (Denmark)

    Ma, Siyuan; Wang, Haoran; Tang, Junchaojie

    2016-01-01

    In single-phase inverters, DC-link capacitors are installed at the DC-link to buffer the ripple power between the AC side and DC side. Active decoupling methods introduce additional circuits at the DC side or AC side to partially or fully supply the ripple power. So that the demanded DC-link capa......In single-phase inverters, DC-link capacitors are installed at the DC-link to buffer the ripple power between the AC side and DC side. Active decoupling methods introduce additional circuits at the DC side or AC side to partially or fully supply the ripple power. So that the demanded DC......-link capacitor capacitance can be decreased. However, few research is about the effect of DC side and AC side decoupling on the DC-link capacitor reliability considering its electro-thermal stresses. This paper presents a quantitative analysis on the lifetime of capacitors with power decoupling circuits...... at the DC side and AC side, respectively. The ripple current spectrum of the capacitors is obtained by double Fourier analysis of a H-bridge inverter with natural sampling PWM modulation. A study case is demonstrated by a 2,000 W H-bridge inverter with 400 V DC-link voltage....

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

    Science.gov (United States)

    Radwan, Ahmed G; Emira, Ahmed A; AbdelAty, Amr M; Azar, Ahmad 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.

  1. 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.

  2. Rehabilitation medicine summit: building research capacity Executive Summary

    Directory of Open Access Journals (Sweden)

    Kemp John D

    2006-01-01

    Full Text Available Abstract The general objective of the "Rehabilitation Medicine Summit: Building Research Capacity" was to advance and promote research in medical rehabilitation by making recommendations to expand research capacity. The five elements of research capacity that guided the discussions were: 1 researchers; 2 research culture, environment, and infrastructure; 3 funding; 4 partnerships; and 5 metrics. The 100 participants included representatives of professional organizations, consumer groups, academic departments, researchers, governmental funding agencies, and the private sector. The small group discussions and plenary sessions generated an array of problems, possible solutions, and recommended actions. A post-Summit, multi-organizational initiative is called to pursue the agendas outlined in this report (see Additional File 1. Additional File 1 A table outlining the Final Action Plan of the Rehabilitation Medicine Summit: Building Research Capacity held on April 28–29, 2005 in Washington, DC. Click here for file

  3. 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.

  4. Application of Distributed DC/DC Electronics in Photovoltaic Systems

    Science.gov (United States)

    Kabala, Michael

    In a typical residential, commercial or utility grade photovoltaic (PV) system, PV modules are connected in series and in parallel to form an array that is connected to a standard DC/AC inverter, which is then connected directly to the grid. This type of standard installation; however, does very little to maximize the energy output of the solar array if certain conditions exist. These conditions could include age, temperature, irradiance and other factors that can cause mismatch between PV modules in an array that severely cripple the output power of the system. Since PV modules are typically connected in series to form a string, the output of the entire string is limited by the efficiency of the weakest module. With PV module efficiencies already relatively low, it is critical to extract the maximum power out of each module in order to make solar energy an economically viable competitor to oil and gas. Module level DC/DC electronics with maximum power point (MPP) tracking solves this issue by decoupling each module from the string in order for the module to operate independently of the geometry and complexity of the surrounding system. This allows each PV module to work at its maximum power point by transferring the maximum power the module is able to deliver directly to the load by either boosting (stepping up) the voltage or bucking (stepping down) the voltage. The goal of this thesis is to discuss the development of a per-module DC/DC converter in order to maximize the energy output of a PV module and reduce the overall cost of the system by increasing the energy harvest.

  5. 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

  6. Compact integrated dc SQUID gradiometer

    Science.gov (United States)

    de Waal, V. J.; Klapwijk, T. M.

    1982-10-01

    An all-niobium integrated system of first-order gradiometer and dc suprconducting quantum interference device (SQUID) has been developed. It is relatively simple to fabricate, has an overall size of 17×12 mm and a sensitivity of 3.5×10-12 T m-1 Hz-1/2.

  7. Compact integrated dc SQUID gradiometer

    Energy Technology Data Exchange (ETDEWEB)

    de Waal, V.J.; Klapwijk, T.M.

    1982-10-01

    An all-niobium integrated system of first-order gradiometer and dc suprconducting quantum interference device (SQUID) has been developed. It is relatively simple to fabricate, has an overall size of 17 x 12 mm and a sensitivity of 3.5 x 10/sup -12/ T m/sup -1/ Hz/sup -1/2/.

  8. Experiments with a DC Motor

    Science.gov (United States)

    Kraftmakher, Yaakov

    2010-01-01

    Experiments with an electric motor provide good opportunity to demonstrate some basic laws of electricity and magnetism. The aim of the experiments with a low-power dc motor is to show how the motor approaches its steady rotation and how its torque, mechanical power and efficiency depend on the rotation velocity. The tight relationship between the…

  9. Borehole DC-6 hydrostratigraphic chart

    International Nuclear Information System (INIS)

    Gephart, R.E.

    1981-09-01

    This hydrostratigraphic chart for Borehole DC-6 identifies the basic stratigraphy and preliminary hydrologic test results. This borehole was cored for obtaining stratigraphic data and only that portion within the Grande Ronde formation remains open for hydrologic testing. The upper two formations were cased and cemented off

  10. Development of toroid-type HTS DC reactor series for HVDC system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwangmin, E-mail: kwangmin81@gmail.com [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Go, Byeong-Soo; Park, Hea-chul; Kim, Sung-kyu; Kim, Seokho [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Lee, Sangjin [Uiduk University, Gyeongju 780-713 (Korea, Republic of); Oh, Yunsang [Vector Fields Korea Inc., Pohang 790-834 (Korea, Republic of); Park, Minwon; Yu, In-Keun [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of)

    2015-11-15

    Highlights: • The authors developed the 400 mH, 400 A class toroid-type HTS DC reactor system. • The target temperature, inductance and operating current are under 20 K at magnet, 400 mH and 400 A, respectively. All target performances of the HTS DC reactor were achieved. • The HTS DC reactor was conducted through the interconnection operation with a LCC type HVDC system. • Now, the authors are studying the 400 mH, 1500 A class toroid-type HTS DC reactor for the next phase HTS DC reactor. - Abstract: This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application.

  11. Development of toroid-type HTS DC reactor series for HVDC system

    International Nuclear Information System (INIS)

    Kim, Kwangmin; Go, Byeong-Soo; Park, Hea-chul; Kim, Sung-kyu; Kim, Seokho; Lee, Sangjin; Oh, Yunsang; Park, Minwon; Yu, In-Keun

    2015-01-01

    Highlights: • The authors developed the 400 mH, 400 A class toroid-type HTS DC reactor system. • The target temperature, inductance and operating current are under 20 K at magnet, 400 mH and 400 A, respectively. All target performances of the HTS DC reactor were achieved. • The HTS DC reactor was conducted through the interconnection operation with a LCC type HVDC system. • Now, the authors are studying the 400 mH, 1500 A class toroid-type HTS DC reactor for the next phase HTS DC reactor. - Abstract: This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application.

  12. DC motor operation controlled from a DC/DC power converter in pulse mode with low duty cycle

    OpenAIRE

    Stefanov, Goce; Kukuseva, Maja; Citkuseva Dimitrovska, Biljana

    2016-01-01

    In this paper pulse mode of operation of DC motor controlled by DC/DC power converter is analyzed. DC motor operation with time intervals in which the motor operates without output load is of interest. In this mode it is possible the motor to restore energy. Also, in the paper are represented calculations for the amount of the restored energy in the pulse mode operation of the motor for different duty cycles.

  13. NASA/DoD Aerospace Knowledge Diffusion Research Project. Report Number 6. The Relationship between the Use of U.S. Government Technical Reports by U.S. Aerospace Engineers and Scientists and Selected Institutional and Sociometric Variables

    Science.gov (United States)

    1991-01-01

    Peter R.; James D. Schriner; Bettie F. Farace ; and Richard V. Farace . The Assessment of NASA Technical Information. NASA CR-181367. Washington, DC... Farace ; and Richard V. Farace . The Assessment of NASA Technical Information. NASA CR-181367. Washington, DC: National Aeronautics and Space

  14. DC to DC power converters and methods of controlling the same

    Science.gov (United States)

    Steigerwald, Robert Louis; Elasser, Ahmed; Sabate, Juan Antonio; Todorovic, Maja Harfman; Agamy, Mohammed

    2012-12-11

    A power generation system configured to provide direct current (DC) power to a DC link is described. The system includes a first power generation unit configured to output DC power. The system also includes a first DC to DC converter comprising an input section and an output section. The output section of the first DC to DC converter is coupled in series with the first power generation unit. The first DC to DC converter is configured to process a first portion of the DC power output by the first power generation unit and to provide an unprocessed second portion of the DC power output of the first power generation unit to the output section.

  15. Simulation analysis of cascade controller for DC-DC bank converter

    International Nuclear Information System (INIS)

    Mahar, M.A.; Abro, M.R.; Larik, A.S.

    2009-01-01

    Power electronic converters are periodic variable structure systems due to their switched operation. During the last few decades several new dc-dc converter topologies have emerged. Buck converter being simple in topology, has recently drawn attraction of many researchers. Basically, a buck converter is highly underdamped system. In order to overcome the developed oscillations in output of this converter, various control techniques have been proposed. However, these techniques are fraught with many drawbacks. This paper focus on a cascade controller based buck topology. Steady state analysis is given in this paper which shows output voltage and inductor current in detail. Dynamic analysis for line and load variation is also presented. The buck topology is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)

  16. Application of digital control techniques for satellite medium power DC-DC converters

    Science.gov (United States)

    Skup, Konrad R.; Grudzinski, Pawel; Nowosielski, Witold; Orleanski, Piotr; Wawrzaszek, Roman

    2010-09-01

    The objective of this paper is to present a work concerning a digital control loop system for satellite medium power DC-DC converters that is done in Space Research Centre. The whole control process of a described power converter bases on a high speed digital signal processing. The paper presents a development of a FPGA digital controller for voltage mode stabilization that was implemented using VHDL. The described controllers are a classical digital PID controller and a bang-bang controller. The used converter for testing is a simple model of 5-20 W, 200 kHz buck power converter. A high resolution digital PWM approach is presented. Additionally a simple and effective solution of filtering of an analog-to-digital converter output is presented.

  17. 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)

  18. Analysis of a high power, resonant DC-DC converter for DC wind turbines

    DEFF Research Database (Denmark)

    Dincan, Catalin Gabriel; Kjær, Philip Carne; Chen, Yu-Hsing

    2018-01-01

    This paper is introducing a new method of operation for a series resonant converter, with intended application in megawatt high-voltage DC wind turbines. Compared to a frequency controlled series resonant converter operated in sub resonant mode, the method (entitled pulse removal technique) allows...

  19. A Biogeochemical and Spectral Analysis of Vegetation Affected by External Abiotic Agents: Results of an Investigation from Kitsap County, Washington

    Science.gov (United States)

    1990-12-01

    delineated using a remote sensing tech- nique, as proposed, the method may provide a faster and more economic means for environmental assessments and for...NC," Economic Geology, vol 78, no. 4, 1983, pp 605-617. Palazzo, A.J., and Leggett, D.C. (1986). Effect and disposition of TNT in a terrestrial...CECOM R&D Tech Lib. Ft Monmouth. NJ; CEHSC-FU-N (Krajewski). Ft Belvoir. VA: Ch of Engrs. DAEN-C’WE-M. Washington. DC:, Ch of Engrs. DAEN- MPU

  20. 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& ...

  1. 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.

  2. 77 FR 58439 - Environmental Impact Statement for the Northeast Corridor Between Washington, DC, New York, NY...

    Science.gov (United States)

    2012-09-20

    ... Regional and Intercity Household Travel Attitudes and Behavior. Type of Request: New information collection... ages of 18 and 74 who have Northeast intercity or regional travel experience during the 12 months prior... just those who experienced a qualifying intercity or regional travel trip to provide more detailed...

  3. Epigenetics and Neural developmental disorders: Washington DC, September 18 and 19, 2006.

    Science.gov (United States)

    Zhao, Xinyu; Pak, ChangHui; Smrt, Richard D; Jin, Peng

    2007-01-01

    Neural developmental disorders, such as autism, Rett Syndrome, Fragile X syndrome, and Angelman syndrome manifest during early postnatal neural development. Although the genes responsible for some of these disorders have been identified, how the mutations of these genes affect neural development is currently unclear. Emerging evidence suggest that these disorders share common underlying defects in neuronal morphology, synaptic connectivity and brain plasticity. In particular, alterations in dendritic branching and spine morphology play a central role in the pathophysiology of most mental retardation disorders, suggesting that common pathways regulating neuronal function may be affected. Epigenetic modulations, mediated by DNA methylation, RNA-associated silencing, and histone modification, can serve as an intermediate process that imprints dynamic environmental experiences on the "fixed" genome, resulting in stable alterations in phenotypes. Disturbance in epigenetic regulations can lead to inappropriate expression or silencing of genes, causing an array of multi-system disorders and neoplasias. Rett syndrome, the most common form of mental retardation in young girls, is due to l mutation of MECP2, encoding a methylated DNA binding protein that translates DNA methylation into gene repression. Angelman syndrome is due to faulty genomic imprinting or maternal mutations in UBE3A. Fragile X Syndrome, in most cases, results from the hypermethylation of FMR1 promoter, hence the loss of expression of functional FMRP protein. Autism, with its complex etiology, may have strong epigenetic link. Together, these observations strongly suggest that epigenetic mechanisms may play a critical role in brain development and etiology of related disorders. This report summarizes the scientific discussions and major conclusions from a recent conference that aimed to gain insight into the common molecular pathways affected among these disorders and discover potential therapeutic targets that have been missed by looking at one disorder at a time.

  4. Southeast Asia: Problems and Prospects Held at Washington, DC on 4-5 December 1984.

    Science.gov (United States)

    1985-06-01

    widespread. Burmese leaders may have sometimes been considered as " embryo Buddhas," but the military leader is equally a part of the Burman tradition. Kings...mentions Aung San as the reincarnation of King Alaungpaya (1752-1 760), the " embryo Buddha" who was as much warrior as religious leader, and Ne Win as...Vietnam which struck Cambodia. ASEAN supports the right of Cambodia to determine its own destiny . This problem is still unresolved because of Vietnam. Only

  5. 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.

  6. (WASHINGTON, DC) A FLUORESCENCE BASED ASSAY FOR DNA DAMAGE INDUCED BY TOXIC INDUSTRIAL CHEMICALS

    Science.gov (United States)

    Numerous natural and man-made agents are continuously released into the environment due to human activity. Many of these agents cause irreversible damage to the normal biological functions leading to morbidity and mortality in the exposed organisms. The possibility of deliberat...

  7. 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…

  8. Invited Speaker Support for SBP Conference Series (SBP 2014) held in April, 2014 in Washington, DC.

    Science.gov (United States)

    2014-07-23

    Forest School of Medicine, for Health Sciences Chandler Johnson, Stanford, for the Behavioral Sciences Amy Silva, Charles River Associates, for...Optimization for Multi-level Networks Brandon Oselio, Alex Kulesza and Alfred Hero Break 9:50 AM Refreshments: muffins, rice cakes, fresh fruit

  9. Antitank Warfare Seminar Held in Washington, DC on 14-15 October 1976.

    Science.gov (United States)

    1976-10-01

    the pants feeling and he could see the slant range to the tank, he would roll out just for a second, stabilize I- his platform and fire and then...steady platform . Then he would immediately make this large turn and he would roll in for attack. (Unintelligible) Your question of whether it was more...wic.A k14flnf .. .uenn wix 10 ode4t 20 km, hintev de’t F’runt wa’~en... .10, 20 mat am Tag, &enn Itch abet achon ei.ne hatbe Stunde An 1~tug hatte

  10. Walter Reed Army Medical Center, Washington, DC Annual Progress Report FY-89. Volume 2. Part 1

    Science.gov (United States)

    1990-01-02

    stew , 15 lamb liver cubes, and 250 cc of water, each labeled with 50 uCu of 99m Technesium sulfur-colloid. The patients lay on the left and right side...meal of commercial beef stew and a liquid radionuclide are ingested. Patients are monitored for 20 minutes in the recumbent position by Nuclear Medicine

  11. Prevention of Fracture in Ship Structure. March 30-31, 1995, Washington, DC

    National Research Council Canada - National Science Library

    1997-01-01

    .... It has been found on many occasions that failures, while unexpected, could have been prevented had currently known information been used in the design, construction, maintenance, and inspection of the ship...

  12. 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.

  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. WATER QUALITY AND THE REPLACEMENT AND REPAIR OF DRINKING WATER INFRASTRUCTURE: THE WASHINGTON, DC CASE STUDY

    Science.gov (United States)

    A major challenge for society in the 21st century will be replacement, design and optimal management of urban infrastructure. It is estimated that the current world wide demand for infrastructure investment is approximately three trillion US dollars annually. Many developing coun...

  15. Seminar on the Professions and Public Life (Washington, DC, June 1998).

    Science.gov (United States)

    London, Scott

    This seminar brought together professionals from three fields--higher education, philanthropy and journalism. Discussed at the seminar was the role that these professions play in public life. It was noted that there is increasing dismay over the public's declining trust in America's institutions. Professional reform efforts to remedy this…

  16. 77 FR 68718 - Safety Zone for Fireworks Display, Upper Potomac River, Alexandria Channel; Washington, DC

    Science.gov (United States)

    2012-11-16

    ... the annual fireworks display is being moved from land to a discharge barge located on the Upper... comments, as well as documents mentioned in this preamble as being available in the docket, go to http...). Upon being hailed by a U.S. Coast Guard vessel, or other Federal, State, or local agency vessel, by...

  17. 76 FR 55157 - Final Public Meeting in Washington, DC for the Proposed Keystone XL Project

    Science.gov (United States)

    2011-09-06

    ..., including environmental, economic, energy security, foreign policy, and pipeline safety concerns. No... and analysis of the national interest, on August 26, 2011 the U.S. Department of State announced..., Bureau of Oceans and International Environmental and Scientific Affairs/Office of Environmental Policy, U...

  18. Canaries in the mine? Gay community, consumption and aspiration in neoliberal Washington, DC

    OpenAIRE

    Lewis, Nathaniel

    2016-01-01

    Gay men have been implicated in neoliberal urban development strategies (e.g. the creative city) as a ‘canary’ population that forecasts growth. Paradoxically, both neoliberal re-development of North American inner-cities and the ways in which gay men become neoliberalised as individuals contribute to the dissolution of urban gay communities. In contrast to discourses of homonormativity, which suggest that gay men’s declining attachments to gay communities stem from new equalities and consequ...

  19. Prehistory of Australia, by lohn Mulvaney and lohan Kamminga, Smithsonian Institution, Washington D.C., 1999

    Directory of Open Access Journals (Sweden)

    Pamela Willoughby

    2000-05-01

    Full Text Available The prehistory of Australia is a fascinating topic. But it has also been a controversial subject, as aborigi­nal populations, settlers, and archaeologists have argued over the past, its ownership and its meaning and interpretation. Derek John Mulvaney has seen Australian archaeology develop from its early days, and in this book, he and co-author Johan Kamminga try to review the latest evidence. It is not clear who the book is intended for but it would include professional archaeologists as well as average Australians, aboriginal and non-aboriginal alike. This is the third edition of a work first published in 1969; a second edition appeared in 1975.

  20. 78 FR 63251 - Board Meeting; November 20, 2013 in Washington, DC

    Science.gov (United States)

    2013-10-23

    ... development activities. Pursuant to its authority under section 5051 of Public Law 100-203, Nuclear Waste... that workshop. The meeting will begin at 8:00 a.m. and will be held at the Embassy Suites Hotel, 1250... hotel for meeting attendees. Reservations can be made online at http://embassysuites.hilton.com/en/es...

  1. 75 FR 39969 - National Mall and Memorial Parks, Washington, DC; Final Environmental Impact Statement and...

    Science.gov (United States)

    2010-07-13

    ... alternatives as well as the focused emphasis of Alternatives A, B, and C. Under the Preferred Alternative, the..., 2010), as well as approximately 30,000 comments received before the DEIS was published, were considered... to the recreational opportunities in adjacent parks, thereby contributing to the concept of healthy...

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

    Science.gov (United States)

    2011-11-09

    I also appreciate speaking early in the lineup of presentations since it minimizes the chance that I will contradict something you have already...Architectures Enterprise Working Meeting (S&T, CAPE, Policy, COCOM) OV-1 Architecture Definition Industry Day Enabling Technology Identification ...year turnaround time  Video: www.youtube.com/usnavyresearch  Requests submitted online www.onr.navy.mil/techsolutions • Ship Identification

  3. Solar Decathlon 2011, The National Mall, Washington, D.C., Fall 2011 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2010-04-01

    This brochure provides a high-level overview of the U.S. Department of Energy Solar Decathlon 2011-the competition's background, purpose, impact, 10 contests, 20 teams, and where to go for additional information.

  4. 77 FR 2450 - Security Zone; Potomac and Anacostia Rivers, Washington, DC

    Science.gov (United States)

    2012-01-18

    ... terrorist acts, and enhance public and maritime safety and security. The Coast Guard was unable to publish a... terrorist acts and enhancing public and maritime safety security. Under 5 U.S.C. 553(d)(3), the Coast Guard...-ranking government officials, mitigating potential terrorist acts and enhancing public and maritime safety...

  5. 76 FR 51255 - Security Zone; Potomac River, Georgetown Channel, Washington, DC

    Science.gov (United States)

    2011-08-18

    ... officials, mitigate potential terrorist acts, and enhance public and maritime safety and security. The Coast... officials, mitigating potential terrorist acts and enhancing public and maritime safety security. Under 5 U... and enhancing public and maritime safety and security. Background and Purpose The President of the...

  6. Group Home Energy Efficiency Retrofit for 30% Energy Savings: Washington, D.C. (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2013-11-01

    Energy efficiency retrofits (EERs) face many challenges on the path to scalability. Limited budgets, cost effectiveness, risk factors, and accessibility impact the type and the extent of measures that can be implemented feasibly to achieve energy savings goals. Group home retrofits can face additional challenges than those in single family homes - such as reduced access (occupant-in-place restrictions) and lack of incentives for occupant behavioral change. This project studies the specification, implementation, and energy savings from an EER in a group home, with an energy savings goal of 30%. This short term test report chronicles the retrofit measures specified, their projected cost-effectiveness using building energy simulations, and the short term test results that were used to characterize pre-retrofit and post-retrofit conditions. Additionally, the final report for the project will include analysis of pre- and post-retrofit performance data on whole building energy use, and an assessment of the energy impact of occupant interface with the building (i.e., window operation). Ultimately, the study's results will be used to identify cost effective EER measures that can be implemented in group homes, given constraints that are characteristic of these buildings. Results will also point towards opportunities for future energy savings.

  7. 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.…

  8. 78 FR 63250 - Workshop; November 18-19, 2013 in Washington, DC

    Science.gov (United States)

    2013-10-23

    ... management system: it likely will take a long time; it will involve extensive SNF handling operations; and... waste-management system. Pursuant to its authority under section 5051 of Public Law 100-203, Nuclear... Severson and Linda Coultry can be reached by telephone at 703-235-4473. Dated: October 16, 2013. Nigel Mote...

  9. World Materials Summit (3rd). Held in Washington, DC on 9-12 October, 2011

    Science.gov (United States)

    2012-05-23

    creates bumps on the backplane of a thin monocrystalline silicon solar cell. This increases the efficiency through a light trapping mechanism. They are...atoms in motion," Brinkman said. The third and fourth days of the Summit were occupied with panel sessions, each discussing one aspect of materials...lighting; energy fuels; water; renewables; and policy and education. Some highlights of the panel reports to the Summit as a whole: • The smart

  10. Remarks before the Paralyzed Veterans of America, Disability Rights Conference (Washington, DC, April 5, 1984).

    Science.gov (United States)

    Reynolds, Wm. Bradford

    This speech by the Assistant Attorney General in the Civil Rights Division of the Department of Justice describes the Reagan Administration's enforcement of section 504 of the Rehabilitation Act and other federal statutes protecting the rights of disabled people in America. The Supreme Court case of "Consolidated Rail Corporation v.…

  11. 76 FR 63841 - Security Zone; Potomac River, Georgetown Channel, Washington, DC

    Science.gov (United States)

    2011-10-14

    ... effect from 6 a.m. until 6 p.m. on October 16, 2011. The security zone will include all navigable waters... security zone at the time it is in effect are to depart the zone immediately. To seek permission to transit... can better evaluate its effects on them and participate in the rulemaking process. Small businesses...

  12. 77 FR 37737 - Environmental Impact Statement for the Northeast Corridor Between Washington, DC, New York, NY...

    Science.gov (United States)

    2012-06-22

    ... City, and Boston, MA. FRA is leading the planning and environmental evaluation of the Northeast..., worse, have reached the point of obsolescence. The need for the project is founded in the importance of... American tribes and to private organizations that might have previously expressed or that are known to have...

  13. Predicting pavement condition index using international roughness index in Washington DC.

    Science.gov (United States)

    2014-09-01

    A number of pavement condition indices are used to conduct pavement management assessments, two of which are the : International Roughness Index (IRI) and Pavement Condition Index (PCI). The IRI is typically measured using specialized : equipment tha...

  14. Symposium on International Terrorism Held in Washington, DC on 2-3 December 1985

    Science.gov (United States)

    1985-12-01

    grievances--an ethnic or religious minority, unemployed university graduates. Their grievances and the vague expectation that revolutionary action will...we increase the psychic production costs for state decision makers. By challenging the behavior and raising public awareness both at home and abroad

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

    Science.gov (United States)

    1983-12-01

    other conditions as lung cancer, major cardiovascular disease, drug and alcohol abuse, and motorcycle and automobile accidents. The remaining data in...response incompatible with anxiety is known as: 1. operant shaping. 2. reciprocal inhibition. 3. Pavlovian conditioning . 4. conditioned reflex... conditions of their service. Labelling contract evasion as a drug rehabilitation treatment failure belies the ~* .~goal of the program as a manpower

  16. 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...

  17. Implementation method of multi-terminal DC control system

    Science.gov (United States)

    Yi, Liu; Hao-Ran, Huang; Jun-Wen, Zhou; Hong-Guang, Guo; Yu-Yong, Zhou

    2018-04-01

    Currently the multi-terminal DC system (MTDC) has more stations. Each station needs operators to monitor and control the device. It needs much more operation and maintenance, low efficiency and small reliability; for the most important reason, multi-terminal DC system has complex control mode. If one of the stations has some problem, the control of the whole system should have problems. According to research of the characteristics of multi-terminal DC (VSC-MTDC) systems, this paper presents a strong implementation of the multi-terminal DC Supervisory Control and Data Acquisition (SCADA) system. This system is intelligent, can be networking, integration and intelligent. A master control system is added in each station to communication with the other stations to send current and DC voltage value to pole control system for each station. Based on the practical application and information feedback in the China South Power Grid research center VSC-MTDC project, this system is higher efficiency and save the cost on the maintenance of convertor station to improve the intelligent level and comprehensive effect. And because of the master control system, a multi-terminal system hierarchy coordination control strategy is formed, this make the control and protection system more efficiency and reliability.

  18. 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...

  19. OffshoreDC DC grids for integration of large scale wind power

    DEFF Research Database (Denmark)

    Zeni, Lorenzo; Endegnanew, Atsede Gualu; Stamatiou, Georgios

    The present report summarizes the main findings of the Nordic Energy Research project “DC grids for large scale integration of offshore wind power – OffshoreDC”. The project is been funded by Nordic Energy Research through the TFI programme and was active between 2011 and 2016. The overall...... objective of the project was to drive the development of the VSC based HVDC technology for future large scale offshore grids, supporting a standardised and commercial development of the technology, and improving the opportunities for the technology to support power system integration of large scale offshore...

  20. Characterising and modelling extended conducted electromagnetic interference in densely packed DC-DC converter

    CSIR Research Space (South Africa)

    Grobler, Inus

    2013-09-01

    Full Text Available . The military specified DC-DC converters are applicable, spanning from 100 W handheld power managers up to 2 kW DC-DC battery chargers. Circuit layout high frequency effects as well as high frequency impedances of the power components were characterised...

  1. Full wave dc-to-dc converter using energy storage transformers

    Science.gov (United States)

    Moore, E. T.; Wilson, T. G.

    1969-01-01

    Full wave dc-to-dc converter, for an ion thrustor, uses energy storage transformers to provide a method of dc-to-dc conversion and regulation. The converter has a high degree of physical simplicity, is lightweight and has high efficiency.

  2. A DC-DC Conversion Powering Scheme for the CMS Phase-1 Pixel Upgrade

    CERN Document Server

    Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Sammet, Jan Domenik; Wlochal, Michael

    2012-01-01

    The powering scheme of the CMS pixel detector will be described, and the performance of prototype DC-DC buck converters will be presented, including power efficiency, system tests with DC-DC converters and pixel modules, thermal management, reliability at low temperature, and studies of potential frequency locking betwe...

  3. Transformerless dc-Isolated Converter

    Science.gov (United States)

    Rippel, Wally E.

    1987-01-01

    Efficient voltage converter employs capacitive instead of transformer coupling to provide dc isolation. Offers buck/boost operation, minimal filtering, and low parts count, with possible application in photovoltaic power inverters, power supplies and battery charges. In photovoltaic inverter circuit with transformerless converter, Q2, Q3, Q4, and Q5 form line-commutated inverter. Switching losses and stresses nil because switching performed when current is zero.

  4. AC-DC PFC Converter Using Combination of Flyback Converter and Full-bridge DC-DC Converter

    Directory of Open Access Journals (Sweden)

    Moh. Zaenal Efendi

    2014-06-01

    Full Text Available This paper presents a combination of power factor correction converter using Flyback converter and Full-bridge dc-dc converter in series connection. Flyback converter is operated in discontinuous conduction mode so that it can serve as a power factor correction converter and meanwhile Full-bridge dc-dc converter is used for dc regulator. This converter system is designed to produce a 86 Volt of output voltage and 2 A of output current. Both simulation and experiment results show that the power factor of this converter achieves up to 0.99 and meets harmonic standard of IEC61000-3-2. Keywords: Flyback Converter, Full-bridge DC-DC Converter, Power Factor Correction.

  5. 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.

  6. 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

    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....

  7. Fiscal 1999 research result report on energy and environment technology demonstration research support project (International joint demonstration research project). Japan- Russia joint demonstration research on large-capacity long- distant DC power transmission technology; 1999 nendo daiyoryo denryoku no chokyori chokuryu soden gijutsu ni kansuru Russia kenkyu kikan tono kyodo jissho kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Under the assumption of a large-capacity DC power transmission model project in the Far East and Siberia districts, technical study was made on the basic design of the project, considering selection of concrete power generation and consumption sites and power transmission routes, power transmission/transformation equipment, cables, and environmental impact. Study was also made on its applicability to similar projects in Japan. The model project aims at integration of Eastern Integrated Power System in the Far East and Russian Unified Power System, and development of abundant undeveloped hydraulic and tidal power generation in the Far East. The study result showed that (1) construction of the high-voltage DC power transmission (HVDC) system of model project class voltage and capacity in Eastern Siberia is possible technically enough, (2) the total construction cost of the model project scheduled to be put into operation in 2025 amounts to nearly $4.7 billion, and (3) the model project is environment-friendly without any CO{sub 2} gas emission because of hydraulic and tidal power generation. (NEDO)

  8. 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.

  9. A Review of Galvanically Isolated Impedance-Source DC–DC Converters

    DEFF Research Database (Denmark)

    Chub, Andrii; Vinnikov, Dmitri; Blaabjerg, Frede

    2016-01-01

    Impedance-source converters, an emerging technology in electric energy conversion, overcome limitations of conventional solutions by the use of specific impedance-source networks. Focus of this paper is on the topologies of galvanically isolated impedance-source dc-dc converters. These converters...... isolated dc-dc converters according to the element that transfers energy from the input to the output: a transformer, a coupled inductor, or their combination. This classification reveals advantages and disadvantages, as well as a wide space for further research. This paper also outlines the most promising...

  10. Harmonic elimination technique for a single-phase multilevel converter with unequal DC link voltage levels

    DEFF Research Database (Denmark)

    Ghasemi, N.; Zare, F.; Boora, A.A.

    2012-01-01

    Multilevel converters, because of the benefits they attract in generating high quality output voltage, are used in several applications. Various modulation and control techniques are introduced by several researchers to control the output voltage of the multilevel converters like space vector...... modulation and harmonic elimination (HE) methods. Multilevel converters may have a DC link with equal or unequal DC voltages. In this study a new HE technique based on the HE method is proposed for multilevel converters with unequal DC link voltage. The DC link voltage levels are considered as additional...

  11. DC servo motor positioning with anti-windup implementation using C2000 ARM-Texas Instrument

    Science.gov (United States)

    Linggarjati, Jimmy

    2017-12-01

    One of the most important topics in control system is DC Motor. At this research, a positioning control system for a DC motor is investigated. Firstly, the DC Motor will be paramaterized to get the transfer function model, in order to be simulated in Matlab, and then implemented in a C2000-ARM microcontroller from TI (Texas Instrument). With this investigation, students in control system theory will be able to understand the importance of classical control theories, in relation to the real world implementation of the position control for the DC Motor, escpecially the importance of Anti-Windup technique in real-world implementation.

  12. 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…

  13. 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…

  14. Quasi-Z-Source Half-Bridge DC-DC Converter for Photovoltaic Applications

    OpenAIRE

    Vinnikov, D; Chub, A; Husev, O; Zaķis, J

    2015-01-01

    This paper presents a novel quasi-Z-source halfbridge galvanically isolated DC-DC converter intended for the photovoltaic applications. The topology could be envisioned as an alternative to the boost half-bridge DC-DC converter but the benefit of its symmetric structure reduces the threat of transformer saturation due to the dc flux. The proposed converter features the continuous input current and could be used either with one or two input voltage sources.

  15. Control of the DC-DC Converter used into Energy Generation System

    International Nuclear Information System (INIS)

    Bizon, Nicu; Oproescu, Mihai

    2006-01-01

    This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)

  16. Washington State biomass data book

    International Nuclear Information System (INIS)

    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

  17. Hybrid electric system based on fuel cell and battery and integrating a single dc/dc converter for a tramway

    International Nuclear Information System (INIS)

    Fernandez, Luis M.; Garcia, Pablo; Garcia, Carlos Andres; Jurado, Francisco

    2011-01-01

    Research highlights: → Hybrid electric power system for a real surface tramway. → Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. → New control strategy for the energy management of the tramway. → Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.

  18. Hybrid electric system based on fuel cell and battery and integrating a single dc/dc converter for a tramway

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Luis M., E-mail: luis.fernandez@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Pablo, E-mail: pablo.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Carlos Andres, E-mail: carlosandres.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, Francisco, E-mail: fjurado@ujaen.e [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, No. 28. 23700 Linares (Jaen) (Spain)

    2011-05-15

    Research highlights: {yields} Hybrid electric power system for a real surface tramway. {yields} Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. {yields} New control strategy for the energy management of the tramway. {yields} Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.

  19. Review on Control of DC Microgrids and Multiple Microgrid Clusters

    DEFF Research Database (Denmark)

    Meng, Lexuan; Shafiee, Qobad; Ferrari-Trecate, Giancarlo

    2017-01-01

    This paper performs an extensive review on control schemes and architectures applied to DC microgrids. It covers multi-layer hierarchical control schemes, coordinated control strategies, plug-and-play operations, stability and active damping aspects as well as nonlinear control algorithms....... Islanding detection, protection and microgrid clusters control are also briefly summarized. All the mentioned issues are discussed with the goal of providing control design guidelines for DC microgrids. The future research challenges, from the authors’ point of view, are also provided in the final...

  20. Development of DC-TOF control software framework

    International Nuclear Information System (INIS)

    Kim, Hong Joo; Kim, Hyun Ok

    2010-06-01

    Disk-Chopper Time-of-Flight spectrometer (DC-TOF) is a new cold neutron instrument under construction at the Korea Atomic Energy Research Institute (KAERI). It will be equipped with a total of 352 2m PSDs(Position Sensitive Detectors), which are grouped into 11 panels. We developed the main DAQ/Control software works well between multi-DSPs of electronics and user. It is convenient to operate DC-TOF system and monitor it's data quality using GUI(Graphical User Interface). Also it satisfies design throughout with test result of 100K events/s

  1. Possibilities of Obtaining Flat Static Characteristic of DC Ferromagnetic Actuator

    Czech Academy of Sciences Publication Activity Database

    Doležel, Ivo; Dvořák, P.; Mach, M.; Ulrych, B.

    2005-01-01

    Roč. 220, č. 1 (2005), s. 29-39 ISSN 0032-6216 R&D Projects: GA MŠk(CZ) LN00B084 Institutional research plan: CEZ:AV0Z20570509 Keywords : flat static characteristic * DC ferromagnetic actuator Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. DC Microgrids Scoping Study. Estimate of Technical and Economic Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Backhaus, Scott N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Swift, Gregory William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chatzivasileiadis, Spyridon [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tschudi, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Glover, Steven [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Starke, Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Yue, Meng [Brookhaven National Lab. (BNL), Upton, NY (United States); Hammerstrom, Donald [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-23

    Microgrid demonstrations and deployments are expanding in US power systems and around the world. Although goals are specific to each site, these microgrids have demonstrated the ability to provide higher reliability and higher power quality than utility power systems and improved energy utilization. The vast majority of these microgrids are based on AC power transfer because this has been the traditionally dominant power delivery scheme. Independently, manufacturers, power system designers and researchers are demonstrating and deploying DC power distribution systems for applications where the end-use loads are natively DC, e.g., computers, solid-state lighting, and building networks. These early DC applications may provide higher efficiency, added flexibility, reduced capital costs over their AC counterparts. Further, when onsite renewable generation, electric vehicles and storage systems are present, DC-based microgrids may offer additional benefits. Early successes from these efforts raises a question - can a combination of microgrid concepts and DC distribution systems provide added benefits beyond what has been achieved individually?

  3. Wideband impedance measurements and modeling of DC motors for EMI predictions

    NARCIS (Netherlands)

    Diouf, F.; Leferink, Frank Bernardus Johannes; Duval, Fabrice; Bensetti, Mohamed

    2015-01-01

    In electromagnetic interference prediction, dc motors are usually modeled as a source and a series impedance. Previous researches only include the impedance of the armature, while neglecting the effect of the motor's rotation. This paper aims at measuring and modeling the wideband impedance of a dc

  4. ZVS Operating Region of Multiresonant DC/DC Boost Conveter

    Directory of Open Access Journals (Sweden)

    Elzbieta Szychta

    2007-01-01

    Full Text Available Electromagnetic phenomena that occur during stable operation in resonant circuits of multiresonant ZVS boost converter are described, which can be applied in many fields of the needs of DC voltage electricity. The operating region of the converter is defined which assures the circuit’s operation in which semiconductor elements are switched at zero voltage (ZVS. Conditions delimiting the ZVS operating region are provided. Analysis of the circuit’s operation is based on results of simulation testing by means of Simplorer software.

  5. 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.

  6. High voltage direct current transmission converters, systems and DC grids

    CERN Document Server

    Jovcic, Dragan

    2015-01-01

    This comprehensive reference guides the reader through all HVDC technologies, including LCC (Line Commutated Converter), 2-level VSC and VSC HVDC based on modular multilevel converters (MMC) for an in-depth understanding of converters, system level design, operating principles and modeling. Written in a tutorial style, the book also describes the key principles of design, control, protection and operation of DC transmission grids, which will be substantially different from the practice with AC transmission grids. The first dedicated reference to the latest HVDC technologies and DC grid developments; this is an essential resource for graduate students and researchers as well as engineers and professionals working on the design, modeling and operation of DC grids and HVDC.

  7. 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.

  8. 76 FR 21712 - Meeting of the Ocean Research and Resources Advisory Industry Sub-Panel

    Science.gov (United States)

    2011-04-18

    ... creative problem-solving to overcome impediments to industry progress toward deploying operational projects... held at the Consortium for Ocean Leadership, 1201 New York Avenue, NW., 4th Floor, Washington, DC 20005...

  9. Experiments with a dc motor

    International Nuclear Information System (INIS)

    Kraftmakher, Yaakov

    2010-01-01

    Experiments with an electric motor provide good opportunity to demonstrate some basic laws of electricity and magnetism. The aim of the experiments with a low-power dc motor is to show how the motor approaches its steady rotation and how its torque, mechanical power and efficiency depend on the rotation velocity. The tight relationship between the mechanical and electrical parameters of the motor is clearly seen. The measurements are carried out with the ScienceWorkshop data-acquisition system and the DataStudio software from PASCO scientific. The experiments are well related to university courses of electricity and magnetism and can be used in undergraduate laboratories or for lecture demonstrations.

  10. Development of toroid-type HTS DC reactor series for HVDC system

    Science.gov (United States)

    Kim, Kwangmin; Go, Byeong-Soo; Park, Hea-chul; Kim, Sung-kyu; Kim, Seokho; Lee, Sangjin; Oh, Yunsang; Park, Minwon; Yu, In-Keun

    2015-11-01

    This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application.

  11. Restoring the Lost Rivers of Washington: Can a city's hydrologic past inform its future?

    OpenAIRE

    Millay, Curtis A.

    2005-01-01

    Washington, D.C., like many older U.S. cities, suffers the woes of rapid urbanization and aging infrastructure. The cityâ s combined sewer and stormwater system dumps millions of gallons of raw sewage into the Anacostia and Potomac Rivers over 70 times annually during significant rain events. While many groups, both public and private, attempt to clean the river, billions of dollars are still necessary over several years to remedy the combined sewer overfl ow (CSO) problem alone. Current pla...

  12. 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…

  13. Reliability of Capacitors for DC-Link Applications in Power Electronic Converters

    DEFF Research Database (Denmark)

    Wang, Huai; Blaabjerg, Frede

    2014-01-01

    DC-link capacitors are an important part in the majority of power electronic converters which contribute to cost, size and failure rate on a considerable scale. From capacitor users' viewpoint, this paper presents a review on the improvement of reliability of dc link in power electronic converters...... from two aspects: 1) reliability-oriented dc-link design solutions; 2) conditioning monitoring of dc-link capacitors during operation. Failure mechanisms, failure modes and lifetime models of capacitors suitable for the applications are also discussed as a basis to understand the physics......-of-failure. This review serves to provide a clear picture of the state-of-the-art research in this area and to identify the corresponding challenges and future research directions for capacitors and their dc-link applications....

  14. Hierarchical Velocity Control Based on Differential Flatness for a DC/DC Buck Converter-DC Motor System

    Directory of Open Access Journals (Sweden)

    R. Silva-Ortigoza

    2014-01-01

    Full Text Available This paper presents a hierarchical controller that carries out the angular velocity trajectory tracking task for a DC motor driven by a DC/DC Buck converter. The high level control is related to the DC motor and the low level control is dedicated to the DC/DC Buck converter; both controls are designed via differential flatness. The high level control provides a desired voltage profile for the DC motor to achieve the tracking of a desired angular velocity trajectory. Then, a low level control is designed to ensure that the output voltage of the DC/DC Buck converter tracks the voltage profile imposed by the high level control. In order to experimentally verify the hierarchical controller performance, a DS1104 electronic board from dSPACE and Matlab-Simulink are used. The switched implementation of the hierarchical average controller is accomplished by means of pulse width modulation. Experimental results of the hierarchical controller for the velocity trajectory tracking task show good performance and robustness against the uncertainties associated with different system parameters.

  15. 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.

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. Southwestern Washington 6 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 6-second Southwest Washington Elevation Grid provides bathymetric data in ASCII raster format of 6-second resolution in geographic coordinates. This grid is...