Science.gov

Sample records for fuel benefits challenges

  1. Orion: challenges and benefits

    NASA Astrophysics Data System (ADS)

    Phipps, Claude R.

    1998-09-01

    ORION is a practical proposal for removing the 150,000 pieces of manmade space debris in the 1- to 10-cm size range now orbiting the Earth below 1500 km altitude which threaten large space systems in low Earth orbit. It is based on using the thrust produced by pulsed laser ablation of a thin layer on the debris surface to drop its perigee sufficiently for reentry and burnup. Applied when the object is rising between about 45 and 15-degree zenith angle, the necessary (Delta) v is of order 100 m/s. A laser of 30 kW average power at 10-ns pulsewidth and a 6-m mirror with adaptive optics can clear near-Earth space of these debris in 2 years of operation. Technical challenges faced by such a system include: heavy demands on detection, tracking and adaptive optics arising from the tiny optical cross section of the smallest debris and the required pointing accuracy and steering rate, stimulated Raman conversion and nonlinear refraction of the laser beam in the atmosphere, uncertainty of momentum coupling coefficients (Cm) for some materials, and high-average-power laser development. It is crucial that the system we propose be developed under international aegis, to insure that its installation does not increase international tensions. It should be viewed as a single-pay lifetime insurance policy for the World's space assets whose premium is less than 1% of the protected asset value, an excellent rate for such contracts.

  2. Used Nuclear Fuel: From Liability to Benefit

    NASA Astrophysics Data System (ADS)

    Orbach, Raymond L.

    2011-03-01

    Nuclear power has proven safe and reliable, with operating efficiencies in the U.S. exceeding 90%. It provides a carbon-free source of electricity (with about a 10% penalty arising from CO2 released from construction and the fuel cycle). However, used fuel from nuclear reactors is highly toxic and presents a challenge for permanent disposal -- both from technical and policy perspectives. The half-life of the ``bad actors'' is relatively short (of the order of decades) while the very long lived isotopes are relatively benign. At present, spent fuel is stored on-site in cooling ponds. Once the used fuel pools are full, the fuel is moved to dry cask storage on-site. Though the local storage is capable of handling used fuel safely and securely for many decades, the law requires DOE to assume responsibility for the used fuel and remove it from reactor sites. The nuclear industry pays a tithe to support sequestration of used fuel (but not research). However, there is currently no national policy in place to deal with the permanent disposal of nuclear fuel. This administration is opposed to underground storage at Yucca Mountain. There is no national policy for interim storage---removal of spent fuel from reactor sites and storage at a central location. And there is no national policy for liberating the energy contained in used fuel through recycling (separating out the fissionable components for subsequent use as nuclear fuel). A ``Blue Ribbon Commission'' has been formed to consider alternatives, but will not report until 2012. This paper will examine alternatives for used fuel disposition, their drawbacks (e.g. proliferation issues arising from recycling), and their benefits. For recycle options to emerge as a viable technology, research is required to develop cost effective methods for treating used nuclear fuel, with attention to policy as well as technical issues.

  3. Orff Ensembles: Benefits, Challenges, and Solutions

    ERIC Educational Resources Information Center

    Taylor, Donald M.

    2012-01-01

    Playing Orff instruments provides students with a wide variety of opportunities to explore creative musicianship. This article examines the benefits of classroom instrument study, common challenges encountered, and viable teaching strategies to promote student success. The ability to remove notes from barred instruments makes note accuracy more…

  4. Online Credit Recovery: Benefits and Challenges

    ERIC Educational Resources Information Center

    Pettyjohn, Teri; LaFrance, Jason

    2014-01-01

    School leaders are faced with selecting programs to support at-risk students in high schools across the United States. Increasingly, supplemental online learning is being selected as an innovative way to assist these students. The purpose of this qualitative study was to understand stakeholders' perceptions of the benefits and challenges of high…

  5. Developing a PPO: challenges and benefits.

    PubMed

    Range, R P

    1984-12-01

    When deciding upon which kind of alternative delivery system to develop, Saint Vincent Charity Hospital and Health Center, Cleveland, selected the preferred provider organization (PPO) mode because of four basic advantages: (1) the health care consumer's freedom to choose providers; (2) effective cost containment; (3) coordination of services among allied providers; and (4) health promotion programs. More specifically, the Ohio Health Choice Plan (OHCP) benefits hospitals by assisting to maintain or increase market share, facilitating prompt claims payments, and improving financial mix. Physicians benefit not only because they receive prompt payment and are not a risk but also because the fee-for-service system is retained and their market shares can also be preserved or enhanced. Employers' advantages include savings through controlled utilization, positive employee relations, and improved management information. Employees' benefits include lower out-of-pocket costs and freedom of choice. As a full-service PPO, the organization provides benefits plans designed to meet each employer's needs as well as actuary services, claims screening and processing, benefits coordination, utilization control, management reporting, health promotion activities, and networking capabilities. Four major challenges do confront PPOs: 1. Start-up and operating costs can be significant; 2. The administrative skills required are different from those used in traditional health care systems; 3. The commitment in implementing and operating a PPO; and 4. All participating providers must genuinely accept the PPO. A PPO's success also can be measured in three ways: the development of a strong network; size of enrollment; and effectiveness in utilization control.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:10269067

  6. The challenges and benefits of lunar exploration

    NASA Technical Reports Server (NTRS)

    Cohen, Aaron

    1992-01-01

    Three decades into the Space Age, the United States is experiencing a fundamental shift in space policy with the adoption of a broad national goal to expand human presence and activity beyond Earth orbit and out into the Solar System. These plans mark a turning point in American space exploration, for they entail a shift away from singular forays to a long-term, evolutionary program of exploration and utilization of space. No longer limited to the technical and operational specifics of any one vehicle or any one mission plan, this new approach will involve a fleet of spacecraft and a stable of off-planet research laboratories, industrial facilities, and exploration programs. The challenges inherent in this program are immense, but so too are the benefits. Central to this new space architecture is the concept of using a lunar base for in-situ resource utilization, and for the development of planetary surface exploration systems, applicable to the Moon, Mars, and other planetary bodies in the Solar System. This paper discusses the technical, economic, and political challenges involved in this new approach, and details the latest thinking on the benefits that could come from bold new endeavors on the final frontier.

  7. Doing clinical research: the challenges and benefits.

    PubMed

    Higgins, Isabel; Parker, Vicki; Keatinge, Diana; Giles, Michelle; Winskill, Rhonda; Guest, Eileen; Kepreotes, Elizabeth; Phelan, Caroline

    2010-06-01

    The need for research in practice is well documented within nursing and other health care disciplines. This acceptance is predicated on the belief that clinically applied research will inform and improve practice and health service delivery resulting in better outcomes for consumers and their families. Nurses, however, find doing clinical research challenging. This paper describes nurses' experiences of doing clinical research. The main challenges of doing clinical research arise from a culture that prioritises practice where nursing work is core business and there is the need to address immediate and short term goals. There are also problems associated with the use of research language amongst clinical nurses and ambiguity in relation to research role expectations. Lack of support and resources for doing research along with keeping up the momentum for a research project also pose significant challenges. The benefits of doing clinical nursing research include experiential learning that has the potential to lead to practice change and improved patient outcomes that are evidence based. PMID:20950198

  8. Undergraduate Research: Opportunities, Challenges, and Benefits

    NASA Astrophysics Data System (ADS)

    Singer, J.

    2001-05-01

    Undergraduate research is one of the best ways students can experience investigative learning. Undergraduates involved in research often cite the experience as the highlight of their education. Because many geoscience departments now recognize the benefits of undergraduate research, they are creating more opportunities for students and are expecting their faculty to provide research mentoring. The Council on Undergraduate Research (CUR) is a national organization of individual and institutional members representing nearly 900 public and private colleges and universities. CUR generates awareness and support for undergraduate research and offers a variety of faculty development opportunities and services. CUR also conducts workshops where teams of faculty develop a campus plan for institutionalizing undergraduate research. A new online registry facilitates matchmaking between undergraduates with research experience and a desire to pursue an advanced degree, and graduate schools seeking high quality students who are well prepared for research. This presentation will describe the role of CUR in supporting undergraduate research, give examples of successful undergraduate research programs, and highlight some of the challenges and benefits of undergraduate research.

  9. Physics challenges for advanced fuel cycle assessment

    SciTech Connect

    Giuseppe Palmiotti; Massimo Salvatores; Gerardo Aliberti

    2014-06-01

    Advanced fuel cycles and associated optimized reactor designs will require substantial improvements in key research area to meet new and more challenging requirements. The present paper reviews challenges and issues in the field of reactor and fuel cycle physics. Typical examples are discussed with, in some cases, original results.

  10. Organisational Blogs: Benefits and Challenges of Implementation

    ERIC Educational Resources Information Center

    Baxter, Gavin J.; Connolly, Thomas M.; Stansfield, Mark H.

    2010-01-01

    Purpose: The purpose of this paper is to identify the theoretical link between blogs and organisational learning. It aims to provide a set of practical guidelines on how to overcome the challenges of implementing an organisational blog. Design/methodology/approach: A literature review will be used to examine blogs and their association towards…

  11. Campus Challenge - Part 2: Benefits and Challenges of BACnet

    DOE PAGESBeta

    Masica, Ken

    2016-01-15

    Additional challenges of implementing a BACnet network in a large campus environment are explored in this article: providing BACnet campus connectivity, protecting BACnet network traffic, and controlling the resulting broadcast traffic. An example of BACnet implementation is also presented, unifying concepts presented in this and Part One of the article.

  12. Risk-benefit perception: The research challenge

    SciTech Connect

    Peelle, E.

    1987-01-01

    Factors predisposing to perception of repositories as risky include the nuclear track record of secrecy and ineptitude, the overconfidence of some pro-nukes and the premature commercialization of an immature technology. Then, in parallel, we have the AEC-DOE track record including a bureaucratic approach involving premature policy decisions and continual changes in nuclear waste policy as demanded by Congress. The confusion of nuclear power with nuclear weapons is encouraged by those whose goal is to get rid of nuclear power. Media coverge feeds on controversy and a crisis, is a major factor in public perception of N-power and repositories as risky. Beyond their actual physical effects, there is the signal value of accidents such as Browns Ferry, Chernobyl, the Hanford tank leaks, Challenger, and TMI. These accidents have signaled that either the managers and operators don't understand the technology well enough to manage it, or worse yet, that the technology itself may not be manageable. With wodefully inadequate science and technology eduation, US citizens are unprepared to make decisions about management and uses of technology or to conduct their own risk evaluations. All of the above is occurring against the backdrop of the widespread and pervasive decline of trust in government and institutions in the past 25 years. And finally, there is Murphy's Law - everyone has some personal knowledge that whatever can go wrong will go wrong some day. In this social context, the tilt is toward perception of repositories as risky.

  13. The challenge of funding hospital employee retirement benefits.

    PubMed

    Román, Christina

    2012-12-01

    Hospitals face a difficult challenge in meeting existing benefits obligations to employees while maintaining financial reserves to invest in electronic health records, quality improvement, and more effective integration of care. Although they may no longer be able to afford offering employees defined-benefit plans, many forward-looking healthcare organizations are finding ways to keep their commitments without sacrificing the balance sheet. One such organization is Scripps Health in San Diego, whose innovative benefits packages have contributed to its being ranked 56th in Fortune's "100 Best Companies to Work For" list in 2012. PMID:23252235

  14. Challenges for fuel cells in transport applications

    NASA Astrophysics Data System (ADS)

    Chalk, Steven G.; Miller, James F.; Wagner, Fred W.

    The US Department of Energy (DOE) and the US automotive industry are working cooperatively under the auspices of the Partnership for a New Generation of Vehicles (PNGV) to develop a six-passenger automobile that can achieve up to 80 miles/gal. These partners are continuing to invest heavily in research and development of polymer electrolyte membrane (PEM) fuel cells as a clean and efficient alternative technology for transport applications. In the past few years, US automakers have made significant advances in fuel cell technology and have announced plans to put fuel cell vehicles on the market by 2004. DOE is working with industry suppliers to address some of the biggest remaining challenges, which include fuel processing and lowering the cost of fuel cell systems. The refueling infrastructure necessary to support fuel cell vehicles presents additional unresolved issues. This paper provides a status report on the PNGV program and provides an overview of the technical accomplishments and future plans of the DOE Fuel Cells for Transportation Program.

  15. Faculty Perception on International Students in Turkey: Benefits and Challenges

    ERIC Educational Resources Information Center

    Acar, Erkan

    2016-01-01

    The purpose of this qualitative case study is to examine faculty perceptions on international students with respect to benefits and challenges of having them in a liberal arts university located in Istanbul, Turkey. The research data were collected through evaluation of pertinent documents of the school and interviews with sixteen faculty members…

  16. Herbaceous Perennials: Placement, benefits and incorporation challenges in diversified landscapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Herbaceous perennial feedstocks will fill numerous and critical roles in the bioenergy landscape. Our objective is to present the benefits and challenges of growing herbaceous perennials and provide regionally-specific scenarios for their use at the landscape scale. The primary herbaceous perennial ...

  17. Use of Demonstration Gardens in Extension: Challenges and Benefits

    ERIC Educational Resources Information Center

    Glen, Charlotte D.; Moore, Gary E.; Jayaratne, K. S. U.; Bradley, Lucy K.

    2014-01-01

    Extension agents' use of demonstration gardens was studied to determine how gardens are employed in horticultural programming, perceived benefits and challenges of using gardens for Extension programming, and desired competencies. Gardens are primarily used to enhance educational efforts by providing hands-on learning experiences. Greatest…

  18. Electronic Payment System in Nigeria: Its Economic Benefits and Challenges

    ERIC Educational Resources Information Center

    Okifo, Joseph; Igbunu, Richard

    2015-01-01

    The crux of this study is on the adoption of E-payment system in Nigeria: Its economic benefits and challenges. The arrival of the internet has taken electronic payments and transactions to an exponential growth level. Consumers could purchase goods and services from the internet and send unencrypted credit card numbers across the network, which…

  19. Santini memorial lecture: Space Challenges and Opportunities for Human Benefit

    NASA Astrophysics Data System (ADS)

    Yarymovych, Michael I.

    2012-06-01

    Since the beginning of the Space Age the public was fascinated by the great challenges that needed to be overcome, but also inspired by the potential benefits that might arise from the utilization of space systems. This lecture examines the major technological breakthroughs that were necessary for many of the key space programs to succeed, and postulates the immediate and future benefits to humanity that became evident as a result of these advances. A dozen programs ranging from Sputnik and Apollo to the Global Navigation Satellite System are reviewed in view of the technical challenges in elements such as propulsion, power, structures, computing, guidance and control, spectrum management and payloads. Challenges in the cost of space launch, large structures, debris mitigation, humans in space and commercial promise are discussed and opportunities for improvements in the future are postulated.

  20. Social media and physicians: Exploring the benefits and challenges.

    PubMed

    Panahi, Sirous; Watson, Jason; Partridge, Helen

    2016-06-01

    Healthcare professionals' use of social media platforms, such as blogs, wikis, and social networking web sites has grown considerably in recent years. However, few studies have explored the perspectives and experiences of physicians in adopting social media in healthcare. This article aims to identify the potential benefits and challenges of adopting social media by physicians and demonstrates this by presenting findings from a survey conducted with physicians. A qualitative survey design was employed to achieve the research goal. Semi-structured interviews were conducted with 24 physicians from around the world who were active users of social media. The data were analyzed using the thematic analysis approach. The study revealed six main reasons and six major challenges for physicians adopting social media. The main reasons to join social media were as follows: staying connected with colleagues, reaching out and networking with the wider community, sharing knowledge, engaging in continued medical education, benchmarking, and branding. The main challenges of adopting social media by physicians were also as follows: maintaining confidentiality, lack of active participation, finding time, lack of trust, workplace acceptance and support, and information anarchy. By revealing the main benefits as well as the challenges of adopting social media by physicians, the study provides an opportunity for healthcare professionals to better understand the scope and impact of social media in healthcare, and assists them to adopt and harness social media effectively, and maximize the benefits for the specific needs of the clinical community. PMID:25038200

  1. Environmental benefits of transport and stationary fuel cells

    NASA Astrophysics Data System (ADS)

    Hart, David; Hörmandinger, Günter

    The potential environmental benefits of using fuel cells in cars, buses and stationary combined heat and power (CHP) plants of different sizes have not been well-researched. This environmental analysis was conducted for the UK on a `full fuel cycle' basis, encompassing all greenhouse gas and regulated pollutant emissions for the supply chain and end-use technology under consideration. Solid polymer fuel cells (SPFCs) with methanol or natural gas reformers were analysed for cars, SPFCs and phosphoric acid fuel cells (PAFCs) with on-board hydrogen for buses. CHP plants were PAFCs or solid oxide fuel cells (SOFCs). Each option was compared with one or more conventional technologies. In all cases fuel cell technologies have substantially reduced emissions in comparison with conventional technologies. Regulated emissions are lowest, by up to two orders of magnitude, and those that do occur are primarily in the fuel supply chain. The fuel cell technologies are more efficient in all cases, and carbon dioxide (CO2) emissions are reduced broadly in line with energy savings. Methane emissions increase due to fuel switching, e.g. from petrol to natural gas powered buses, but from a very low base. The study pinpoints some areas in which alternative approaches could be made - the methods for generating and transporting hydrogen have a significant bearing on energy consumption and emissions. However, it is clear that from an overall emissions perspective the use of fuel cells in transport and power generation is highly beneficial.

  2. Multidimensional Challenges and Benefits of the CASSIOPE Mission

    NASA Astrophysics Data System (ADS)

    Yau, A.; James, G.; Enno, G.; Hum, R.; Duggan, P.; Senez, M.; Ali, Z.; Brassard, G.; Desjardins, B.; Dubé, L.; Guroux, R.; Beattie, D.; Walkty, I.

    2008-08-01

    We discuss both the synergistic benefits and the challenges of the multi-purpose Canadian CASSIOPE small satellite mission, in which we merge a science mission (e-POP), a technology demonstration mission (CASCADE), and the Canadian Small Satellite Bus Development Program into a single mission. The scientific objectives of the mission concentrate on understanding the central role of the polar ionosphere in moderating the exchange of energy and mass among the ionosphere, thermosphere and magnetosphere. The cross- disciplinary merger posed a number of technical and programmatic challenges on both payloads and the spacecraft bus, including a stringent level of electro- magnetic cleanliness and surface electrical conductivity for plasma and high-sensitivity electric and magnetic field measurements on e-POP; differences in development philosophies, mission reliability requirements, and product assurance-cost tradeoff between the two payloads and between mission subsystems, and cost- effective management of technical and programmatic interfaces between subsystems and between development teams. As well, the mission exemplifies the significant benefits that can be achieved with efficient and pragmatic cooperation between development teams and practical, "outside-the-box" problem solving in addressing these challenges.

  3. A methodology for assessing the market benefits of alternative motor fuels: The Alternative Fuels Trade Model

    SciTech Connect

    Leiby, P.N.

    1993-09-01

    This report describes a modeling methodology for examining the prospective economic benefits of displacing motor gasoline use by alternative fuels. The approach is based on the Alternative Fuels Trade Model (AFTM). AFTM development was undertaken by the US Department of Energy (DOE) as part of a longer term study of alternative fuels issues. The AFTM is intended to assist with evaluating how alternative fuels may be promoted effectively, and what the consequences of substantial alternative fuels use might be. Such an evaluation of policies and consequences of an alternative fuels program is being undertaken by DOE as required by Section 502(b) of the Energy Policy Act of 1992. Interest in alternative fuels is based on the prospective economic, environmental and energy security benefits from the substitution of these fuels for conventional transportation fuels. The transportation sector is heavily dependent on oil. Increased oil use implies increased petroleum imports, with much of the increase coming from OPEC countries. Conversely, displacement of gasoline has the potential to reduce US petroleum imports, thereby reducing reliance on OPEC oil and possibly weakening OPEC`s ability to extract monopoly profits. The magnitude of US petroleum import reduction, the attendant fuel price changes, and the resulting US benefits, depend upon the nature of oil-gas substitution and the supply and demand behavior of other world regions. The methodology applies an integrated model of fuel market interactions to characterize these effects.

  4. Materials Challenges for Automotive PEM Fuel Cells

    NASA Astrophysics Data System (ADS)

    Gasteiger, Hubert

    2004-03-01

    Over the past few years, significant R efforts aimed at meeting the challenging cost and performance targets required for the use of Polymer Electrolyte Membrane (PEM) fuel cells in automotive applications. Besides engineering advances in bipolar plate materials and design, the optimization of membrane-electrode assemblies (MEAs) was an important enabler in reducing the cost and performance gaps towards commercial viability for the automotive market. On the one hand, platinum loadings were reduced from several mgPt/cm2MEA [1] to values of 0.5-0.6 mgPt/cm2MEA in current applications and loadings as low as 0.25 mgPt/cm2MEA have been demonstrated on the research level [2]. On the other hand, implementation of thin membranes (20-30 micrometer) [3, 4] as well as improvements in diffusion medium materials, essentially doubled the achievable power density of MEAs to ca. 0.9 W/cm2MEA (at 0.65 V) [5], thereby not only reducing the size of a PEMFC fuel cell system, but also reducing its overall materials cost (controlled to a large extent by membrane and Pt-catalyst cost). While this demonstrated a clear path towards automotive applications, a renewed focus of R efforts is now required to develop materials and fundamental materials understanding to assure long-term durability of PEM fuel cells. This presentation therefore will discuss the state-of-the-art knowledge of catalyst, catalyst-support, and membrane degradation mechanisms. In the area of Pt-catalysts, experience with phosphoric acid fuel cells (PAFCs) has shown that platinum sintering leads to long-term performance losses [6]. While this is less critical at the lower PEMFC operating temperatures (<100C) compared to PAFCs (>200C), very little is known about the dependence of Pt-sintering on temperature, cell voltage, and catalyst type (i.e., Pt versus Pt-alloys) and will be discussed here. Similarly, carbon-support corrosion can contribute significantly to voltage degradation in PAFCs [7], and even in the PEMFC

  5. Empowering patients through social media: the benefits and challenges.

    PubMed

    Househ, Mowafa; Borycki, Elizabeth; Kushniruk, Andre

    2014-03-01

    This article explores the range of social media platforms used by patients and examines the benefits and challenges of using these tools from a patient perspective. A literature review was performed to investigate the use of social media technology by patients. The MEDLINE database was searched using the terms "social media" and "patient." The search was conducted in September 2012 and yielded 765 abstracts. Initially, 63 abstracts were selected. All articles dating from 2004 through 2012 were included. Only 12 articles were found to be relevant for the purposes of the review. The results of this research found that there appears to be an increase in the use of social media by patients across the healthcare spectrum. The research indicates a promising future for the use of social media by patients; however, evidence related to the efficacy and effectiveness of social media is currently limited. Various challenges have also been identified relating to privacy and security concerns, usability, the manipulation of identity, and misinformation. The use of social media technology is an emerging trend for patients who are seeking health information. Conclusions are that such technology holds promise for improving patient engagement and empowerment and community building. Social media has a future in healthcare, especially with regard to patient engagement and empowerment; however, there are several challenges to overcome before the technology can achieve its potential. PMID:24550564

  6. Materials Challenges for Automotive PEM Fuel Cells

    NASA Astrophysics Data System (ADS)

    Gasteiger, Hubert

    2004-03-01

    Over the past few years, significant R efforts aimed at meeting the challenging cost and performance targets required for the use of Polymer Electrolyte Membrane (PEM) fuel cells in automotive applications. Besides engineering advances in bipolar plate materials and design, the optimization of membrane-electrode assemblies (MEAs) was an important enabler in reducing the cost and performance gaps towards commercial viability for the automotive market. On the one hand, platinum loadings were reduced from several mgPt/cm2MEA [1] to values of 0.5-0.6 mgPt/cm2MEA in current applications and loadings as low as 0.25 mgPt/cm2MEA have been demonstrated on the research level [2]. On the other hand, implementation of thin membranes (20-30 micrometer) [3, 4] as well as improvements in diffusion medium materials, essentially doubled the achievable power density of MEAs to ca. 0.9 W/cm2MEA (at 0.65 V) [5], thereby not only reducing the size of a PEMFC fuel cell system, but also reducing its overall materials cost (controlled to a large extent by membrane and Pt-catalyst cost). While this demonstrated a clear path towards automotive applications, a renewed focus of R efforts is now required to develop materials and fundamental materials understanding to assure long-term durability of PEM fuel cells. This presentation therefore will discuss the state-of-the-art knowledge of catalyst, catalyst-support, and membrane degradation mechanisms. In the area of Pt-catalysts, experience with phosphoric acid fuel cells (PAFCs) has shown that platinum sintering leads to long-term performance losses [6]. While this is less critical at the lower PEMFC operating temperatures (<100C) compared to PAFCs (>200C), very little is known about the dependence of Pt-sintering on temperature, cell voltage, and catalyst type (i.e., Pt versus Pt-alloys) and will be discussed here. Similarly, carbon-support corrosion can contribute significantly to voltage degradation in PAFCs [7], and even in the PEMFC

  7. Miniaturized biological and electrochemical fuel cells: challenges and applications.

    PubMed

    Yang, Jie; Ghobadian, Sasan; Goodrich, Payton J; Montazami, Reza; Hashemi, Nastaran

    2013-09-14

    This paper discusses the fundamentals and developments of miniaturized fuel cells, both biological and electrochemical. An overview of microfluidic fuel cells, miniaturized microbial fuel cells, enzymatic biofuel cells, and implanted biofuel cells in an attempt to provide green energy and to power implanted microdevices is provided. Also, the challenges and applications of each type of fuel cell are discussed in detail. Most recent developments in fuel cell technologies such as novel catalysts, compact designs, and fabrication methods are reviewed. PMID:23503374

  8. Microscale microbial fuel cells: Advances and challenges.

    PubMed

    Choi, Seokheun

    2015-07-15

    The next generation of sustainable energy could come from microorganisms; evidence that it can be seen with the given rise of Electromicrobiology, the study of microorganisms' electrical properties. Many recent advances in electromicrobiology stem from studying microbial fuel cells (MFCs), which are gaining acceptance as a future alternative "green" energy technology and energy-efficient wastewater treatment method. MFCs are powered by living microorganisms with clean and sustainable features; they efficiently catalyse the degradation of a broad range of organic substrates under natural conditions. There is also increasing interest in photosynthetic MFCs designed to harness Earth's most abundant and promising energy source (solar irradiation). Despite their vast potential and promise, however, MFCs and photosynthetic MFCs have not yet successfully translated into commercial applications because they demonstrate persistent performance limitations and bottlenecks associated with scaling up. Instead, microscale MFCs have received increasing attention as a unique platform for various applications such as powering small portable electronic elements in remote locations, performing fundamental studies of microorganisms, screening bacterial strains, and toxicity detection in water. Furthermore, the stacking of miniaturized MFCs has been demonstrated to offer larger power densities than a single macroscale MFC in terms of scaling up. In this overview, we discuss recent achievements in microscale MFCs as well as their potential applications. Further scientific and technological challenges are also reviewed. PMID:25703724

  9. Nanotechnology: Scientific challenges and societal benefits and risks

    NASA Astrophysics Data System (ADS)

    Romig, A. D.

    2004-12-01

    The field of nanotechnology is developing rapidly, as are its practical application in society. In this article, we give examples that demonstrate the enormous potential that exists for this new class of materials, and for devices with critical dimensions of less than 100 nm. We also identify some of the challenges that need to be faced in order to fully realize the practical benefits of nanotechnology, and discuss possible risks that may come with this new technology. In all cases, the unique advantage of nanotechnology can be traced back to nanoscale physical and chemical properties that are quite different from those encountered in more traditional microscopic (micro) or macroscopic (macro) materials and devices. Unique nanoscale properties and behaviors are already being used to increase energy efficiency, improve healthcare, and strengthen national security. However, while progress is rapid, many challenges remain. These include manufacturing at the nanoscale, integration of nanoscale materials and devices with more conventional technology, and predictive modeling that will allow nanotechnology to be engineered reliably into useful applications and products. Nanotechnology can be expected to have an increasing impact on human lives and society at large. As we strive to use nanotechnology to improve human life through better healthcare, cleaner environment, and improved national security, we must also work to detect and assess the negative impacts that nanotechnology science (or any new technology) might bring. We suggest that the conduct of should be allowed to proceed unimpeded, so that we can fully understand and appreciate the rules of nature at the nanometer scale. That said, scientific pursuits that involve self-replication in synthetic systems, encryption, defense technology, or the enhancement of human intelligence should be reviewed. The development of new technology from fundamental science and the process of deciding what new technology is to be

  10. A Vulnerability-Benefit Analysis of Fossil Fuel CO2 Emissions

    NASA Astrophysics Data System (ADS)

    Delman, E. M.; Stephenson, S. R.; Davis, S. J.; Diffenbaugh, N. S.

    2015-12-01

    Although we can anticipate continued improvements in our understanding of future climate impacts, the central challenge of climate change is not scientific, but rather political and economic. In particular, international climate negotiations center on how to share the burden of uncertain mitigation and adaptation costs. We expose the relative economic interests of different countries by assessing and comparing their vulnerability to climate impacts and the economic benefits they derive from the fossil fuel-based energy system. Vulnerability refers to the propensity of humans and their assets to suffer when impacted by hazards, and we draw upon the results from a number of prior studies that have quantified vulnerability using multivariate indices. As a proxy for benefit, we average CO2 related to each country's extraction of fossil fuels, production of CO2 emissions, and consumption of goods and services (Davis et al., 2011), which should reflect benefits accrued in proportion to national economic dependence on fossil fuels. We define a nondimensional vulnerability-benefit ratio for each nation and find a large range across countries. In general, we confirm that developed and emerging economies such as the U.S., Western Europe, and China rely heavily on fossil fuels and have substantial resources to respond to the impacts of climate change, while smaller, less-developed economies such as Sierra Leone and Vanuatu benefit little from current CO2 emissions and are much more vulnerable to adverse climate impacts. In addition, we identify some countries with a high vulnerability and benefit, such as Iraq and Nigeria; conversely, some nations exhibit both a low vulnerability and benefit, such as New Zealand. In most cases, the ratios reflect the nature of energy-climate policies in each country, although certain nations - such as the United Kingdom and France - assume a level of responsibility incongruous with their ratio and commit to mitigation policy despite

  11. Top Benefits Challenges Facing School Business Decision Makers

    ERIC Educational Resources Information Center

    Bohling, Joseph

    2012-01-01

    What's the main factor coloring employee satisfaction? Many organizations' leaders think the answer is salary, yet in reality, employee benefits packages are one of the biggest incentives an employer can offer. Educational institutions have done well in providing benefits to employees. However, with an unpredictable economic climate and a complex…

  12. Benefits and Challenges of School-Based Crisis Response Teams.

    ERIC Educational Resources Information Center

    Kline, Marsha; And Others

    1995-01-01

    Offers a rationale for the importance of school-based intervention in crisis and emergency situations, outlining a model for crisis response policies and procedures. Discusses benefits to schools of developing a team to implement the model, obstacles that can impede full implementation, and strategies for minimizing identified obstacles. (SM)

  13. Online Distance Learning and Music Training: Benefits, Drawbacks and Challenges

    ERIC Educational Resources Information Center

    Koutsoupidou, Theano

    2014-01-01

    This study examines online distance learning (ODL) as applied in music and music education programmes at different educational levels with a special focus on the digital tools employed in such programmes. It aims to provide an up-to-date snapshot of the current online courses focusing on the potential benefits and drawbacks of ODL from the…

  14. Benefits and Challenges of Achieving a Mainstream Market for Electric Vehicles

    SciTech Connect

    Ungar, Edward; Mueller, Howard; Smith, Brett

    2010-08-01

    The Plug-in Hybrid electric Vehicle (PHEV) Market Introduction Study Final Report identified a range of policies, incentives and regulations designed to enhance the probability of success in commercializing PHEVs as they enter the automotive marketplace starting in 2010. The objective of the comprehensive PHEV Value Proposition study, which encompasses the PHEV Market Introduction Study, is to better understand the value proposition that PHEVs (as well as other plug-in electric vehicle platforms - PEVs) provide to the auto companies themselves, to the consumer and to the public at large as represented by the government and its public policies. In this report we use the more inclusive term PEVs, to include PHEVs, BEVs (battery electric vehicles that operate only on battery) and EREVs (extended range electric vehicles that combine battery electric vehicles with an internal combustion engine that charges the battery as needed). The objective of Taratec's contribution to Phase 2 of the PHEV Value Proposition Study is to develop a clear understanding of the benefits of PEVs to three stakeholders - auto original equipment manufacturers (OEMs), utilities, and the government - and of the technical and commercial challenges and risks to be overcome in order to achieve commercial success for these vehicles. The goal is to understand the technical and commercial challenges in moving from the 'early adopters' at the point of market introduction of these vehicles to a 'sustainable' mainstream market in which PEVs and other PEVs represent a normal, commercially available and attractive vehicle to the mainstream consumer. For the purpose of this study, that sustainable market is assumed to be in place in the 2030 timeframe. The principal focus of the study is to better understand the technical and commercial challenges in the transition from early adopters to a sustainable mainstream consumer market. Effectively, that translates to understanding the challenges to be overcome

  15. Borderland Spaces for Learning Partnership: Opportunities, Benefits and Challenges

    ERIC Educational Resources Information Center

    Hill, Jennifer; Thomas, Greg; Diaz, Anita; Simm, David

    2016-01-01

    This paper uses case studies and secondary literature to critically examine how learning spaces inhabited by geographers might be used productively as borderland spaces for learning partnership. Borderland spaces are novel, challenging, permissive and liminal, destabilizing traditional power hierarchies. In these spaces, students gain confidence…

  16. Wireless Intra-Spacecraft Communication: The Benefits and the Challenges

    NASA Technical Reports Server (NTRS)

    Zheng, Will H.; Armstrong, John T.

    2010-01-01

    In this paper we present a systematic study of how intra-spacecraft wireless communication can be adopted to various subsystems of the spacecraft including C&DH (Command & Data Handling), Telecom, Power, Propulsion, and Payloads, and the interconnects between them. We discuss the advantages of intra-spacecraft wireless communication and the disadvantages and challenges and a proposal to address them.

  17. Nitrogen fertilization challenges the climate benefit of cellulosic biofuels

    NASA Astrophysics Data System (ADS)

    Ruan, Leilei; Bhardwaj, Ajay K.; Hamilton, Stephen K.; Robertson, G. Philip

    2016-06-01

    Cellulosic biofuels are intended to improve future energy and climate security. Nitrogen (N) fertilizer is commonly recommended to stimulate yields but can increase losses of the greenhouse gas nitrous oxide (N2O) and other forms of reactive N, including nitrate. We measured soil N2O emissions and nitrate leaching along a switchgrass (Panicum virgatum) high resolution N-fertilizer gradient for three years post-establishment. Results revealed an exponential increase in annual N2O emissions that each year became stronger (R 2 > 0.9, P < 0.001) and deviated further from the fixed percentage assumed for IPCC Tier 1 emission factors. Concomitantly, switchgrass yields became less responsive each year to N fertilizer. Nitrate leaching (and calculated indirect N2O emissions) also increased exponentially in response to N inputs, but neither methane (CH4) uptake nor soil organic carbon changed detectably. Overall, N fertilizer inputs at rates greater than crop need curtailed the climate benefit of ethanol production almost two-fold, from a maximum mitigation capacity of ‑5.71 ± 0.22 Mg CO2e ha‑1 yr‑1 in switchgrass fertilized at 56 kg N ha‑1 to only ‑2.97 ± 0.18 Mg CO2e ha‑1 yr‑1 in switchgrass fertilized at 196 kg N ha‑1. Minimizing N fertilizer use will be an important strategy for fully realizing the climate benefits of cellulosic biofuel production.

  18. Nitrogen fertilization challenges the climate benefit of cellulosic biofuels

    DOE PAGESBeta

    Ruan, Leilei; Bhardwaj, Ajay K.; Hamilton, Stephen K.; Robertson, G. Philip

    2016-06-01

    Cellulosic biofuels are intended to improve future energy and climate security. Nitrogen (N) fertilizer is commonly recommended to stimulate yields but can increase losses of the greenhouse gas nitrous oxide (N2O) and other forms of reactive N, including nitrate. We measured soil N2O emissions and nitrate leaching along a switchgrass (Panicum virgatum) high resolution N-fertilizer gradient for three years post-establishment. Results revealed an exponential increase in annual N2O emissions that each year became stronger (R2 > 0.9, P < 0.001) and deviated further from the fixed percentage assumed for IPCC Tier 1 emission factors. Concomitantly, switchgrass yields became less responsivemore » each year to N fertilizer. Nitrate leaching (and calculated indirect N2O emissions) also increased exponentially in response to N inputs, but neither methane (CH4) uptake nor soil organic carbon changed detectably. Overall, N fertilizer inputs at rates greater than crop need curtailed the climate benefit of ethanol production almost two-fold, from a maximum mitigation capacity of–5.71 ± 0.22 Mg CO2e ha–1 yr–1 in switchgrass fertilized at 56 kgNha–1 to only –2.97 ± 0.18 MgCO2e ha–1 yr–1 in switchgrass fertilized at 196 kgNha–1. In conclusion, minimizing N fertilizer use will be an important strategy for fully realizing the climate benefits of cellulosic biofuel production.« less

  19. Costs and benefits of automotive fuel economy improvement: A partial analysis

    SciTech Connect

    Greene, D.L.; Duleep, K.G.

    1992-03-01

    This paper is an exercise in estimating the costs and benefits of technology-based fuel economy improvements for automobiles and light trucks. Benefits quantified include vehicle cots, fuel savings, consumer`s surplus effects, the effect of reduced weight on vehicle safety, impacts on emissions of CO{sub 2} and criteria pollutants, world oil market and energy security benefits, and the transfer of wealth from US consumes to oil producers. A vehicle stock model is used to capture sales, scrappage, and vehicle use effects under three fuel price scenarios. Three alternative fuel economy levels for 2001 are considered, ranging from 32.9 to 36.5 MPG for cars and 24.2 to 27.5 MPG for light trucks. Fuel economy improvements of this size are probably cost-effective. The size of the benefit, and whether there is a benefit, strongly depends on the financial costs of fuel economy improvement and judgments about the values of energy security, emissions, safety, etc. Three sets of values for eight parameters are used to define the sensitivity of costs and benefits to key assumptions. The net present social value (1989$) of costs and benefits ranges from a cost of $11 billion to a benefit of $286 billion. The critical parameters being the discount rate (10% vs. 3%) and the values attached to externalities. The two largest components are always the direct vehicle costs and fuel savings, but these tend to counterbalance each other for the fuel economy levels examined here. Other components are the wealth transfer, oil cost savings, CO{sub 2} emissions reductions, and energy security benefits. Safety impacts, emissions of criteria pollutants, and consumer`s surplus effects are relatively minor components. The critical issues for automotive fuel economy are therefore: (1) the value of present versus future costs and benefits, (2) the values of external costs and benefits, and (3) the financially cost-effective level of MPG achievable by available technology. 53 refs.

  20. Costs and benefits of automotive fuel economy improvement: A partial analysis

    SciTech Connect

    Greene, D.L. ); Duleep, K.G. )

    1992-03-01

    This paper is an exercise in estimating the costs and benefits of technology-based fuel economy improvements for automobiles and light trucks. Benefits quantified include vehicle cots, fuel savings, consumer's surplus effects, the effect of reduced weight on vehicle safety, impacts on emissions of CO{sub 2} and criteria pollutants, world oil market and energy security benefits, and the transfer of wealth from US consumes to oil producers. A vehicle stock model is used to capture sales, scrappage, and vehicle use effects under three fuel price scenarios. Three alternative fuel economy levels for 2001 are considered, ranging from 32.9 to 36.5 MPG for cars and 24.2 to 27.5 MPG for light trucks. Fuel economy improvements of this size are probably cost-effective. The size of the benefit, and whether there is a benefit, strongly depends on the financial costs of fuel economy improvement and judgments about the values of energy security, emissions, safety, etc. Three sets of values for eight parameters are used to define the sensitivity of costs and benefits to key assumptions. The net present social value (1989$) of costs and benefits ranges from a cost of $11 billion to a benefit of $286 billion. The critical parameters being the discount rate (10% vs. 3%) and the values attached to externalities. The two largest components are always the direct vehicle costs and fuel savings, but these tend to counterbalance each other for the fuel economy levels examined here. Other components are the wealth transfer, oil cost savings, CO{sub 2} emissions reductions, and energy security benefits. Safety impacts, emissions of criteria pollutants, and consumer's surplus effects are relatively minor components. The critical issues for automotive fuel economy are therefore: (1) the value of present versus future costs and benefits, (2) the values of external costs and benefits, and (3) the financially cost-effective level of MPG achievable by available technology. 53 refs.

  1. Life cycle benefits, challenges, and the potential of recycled aluminum

    SciTech Connect

    Martchek, K.J.

    1997-12-31

    Recently, a number of prominent articles have appeared in the national press questioning the environmental benefits and economic rationale of post consumer materials recycling. This paper reviews the evolution of aluminum recycling and then examines its role in the life cycle of aluminum products based on the most recent industry studies conducted in Europe and North America. The environmental and economic viability of today`s recovery and reuse of aluminum products is explored based on these life cycle assessments and current market conditions. This paper then summarizes technology and issues associated with aluminum recycling including the current state of automotive aluminum dismantling, shredding, recycle and reuse. Afterwards, the paper highlights opportunities for recovering the full environmental and economic potential of aluminum recycling based on emerging technologies, ``producer responsibility`` legislation, voluntary initiatives, and product design considerations.

  2. Capacity building in emerging space nations: Experiences, challenges and benefits

    NASA Astrophysics Data System (ADS)

    Jason, Susan; da Silva Curiel, Alex; Liddle, Doug; Chizea, Francis; Leloglu, Ugur Murat; Helvaci, Mustafa; Bekhti, Mohammed; Benachir, Djouad; Boland, Lee; Gomes, Luis; Sweeting, Martin

    2010-09-01

    This paper focuses on ways in which space is being used to build capacity in science and technology in order to: Offer increasing support for national and global solutions to current and emerging problems including: how to improve food security; resource management; understanding the impacts of climate change and how to deal with them; improving disaster mitigation, management and response. Support sustainable economic development. We present some of the experiences, lessons learned and benefits gained in capacity building projects undertaken by Surrey Satellite Technology Ltd. and our partners from developing and mature space nations. We focus on the Turkish, Algerian and Nigerian know-how and technology transfer programmes which form part of the first Disaster Monitoring Constellation (DMC) in orbit. From the lessons learned on Surrey's know-how and technology transfer partnership programmes, it is clear that space technology needs to be implemented responsibly as part of a long-term capacity building plan to be a sustainable one. It needs to be supported with appropriate policy and legal frameworks, institutional development, including community participation, human resources development and strengthening of managerial systems. In taking this on board, DMC has resulted in a strong international partnership combining national objectives, humanitarian aid and commerce. The benefits include: Ownership of space-based and supporting ground assets with low capital expenditure that is in line with national budgets of developing nations. Ownership of data and control over data acquisition. More for the money via collaborative consortium. Space related capacity building in organisations and nations with the goal of sustainable development. Opportunities for international collaboration, including disaster management and relief.

  3. Benefits and challenges of electronic surveillance in nursing home research.

    PubMed

    Sifford, K Susan; Bharucha, Ashok

    2010-01-01

    Cognitive impairment and frailty associated with dementia renders residents of long-term care (LTC) facilities particularly vulnerable to physical and emotional harm. Resident-to-resident violence affects not only the target of the aggression, but also the aggressor, as well as the formal and informal caregivers who must intervene. To date, little research has been conducted on resident-to-resident violence despite preliminary but emerging evidence that it is a common (and likely growing) problem in LTC settings. Exploration of this phenomenon presents multiple pragmatic and ethical challenges. This article presents a rationale for implementing newer technological methods to collect data in investigations of resident-to-resident violence associated with dementia. The advantages and disadvantages of electronic surveillance in LTC research and the ethical principles involved are discussed, and an argument is developed for using electronic surveillance in both the shared, as well as private, spaces of the facility. PMID:20128538

  4. Providing Undergraduate Science Partners for Elementary Teachers: Benefits and Challenges

    PubMed Central

    Goebel, Camille A.; Umoja, Aminata

    2009-01-01

    Undergraduate college “science partners” provided content knowledge and a supportive atmosphere for K–5 teachers in a university–school professional development partnership program in science instruction. The Elementary Science Education Partners program, a Local Systemic Change initiative supported by the National Science Foundation, was composed of four major elements: 1) a cadre of mentor teachers trained to provide district-wide teacher professional development; 2) a recruitment and training effort to place college students in classrooms as science partners in semester-long partnerships with teachers; 3) a teacher empowerment effort termed “participatory reform”; and 4) an inquiry-based curriculum with a kit distribution and refurbishment center. The main goals of the program were to provide college science students with an intensive teaching experience and to enhance teachers' skills in inquiry-based science instruction. Here, we describe some of the program's successes and challenges, focusing primarily on the impact on the classroom teachers and their science partners. Qualitative analyses of data collected from participants indicate that 1) teachers expressed greater self-confidence about teaching science than before the program and they spent more class time on the subject; and 2) the college students modified deficit-model negative assumptions about the children's science learning abilities to express more mature, positive views. PMID:19723818

  5. The Benefits and Challenges Hospitality Management Students Experience by Working in Conjunction with Completing Their Studies

    ERIC Educational Resources Information Center

    Schoffstall, Donald G.

    2013-01-01

    Previous researchers have suggested that in order to be successful in the hospitality industry, students need to obtain work experience in addition to completing their degrees. Although the benefit of gaining such experience from the industry viewpoint has been well documented, few studies have assessed the benefits and challenges faced by…

  6. Investigating the Benefits and Challenges of Using Laptop Computers in Higher Education Classrooms

    ERIC Educational Resources Information Center

    Kay, Robin Holding; Lauricella, Sharon

    2014-01-01

    The purpose of this study was to investigate the benefits and challenges using laptop computers (hereafter referred to as laptops) inside and outside higher education classrooms. Quantitative and qualitative data were collected from 156 university students (54 males, 102 females) enrolled in either education or communication studies. Benefits of…

  7. Telecytology: Clinical applications, current challenges, and future benefits

    PubMed Central

    Thrall, Michael; Pantanowitz, Liron; Khalbuss, Walid

    2011-01-01

    Telecytology is the interpretation of cytology material at a distance using digital images. For more than a decade, pioneering efforts to introduce telecytology into clinical practice have been reported. A Medline search for “telecytology” and “cytology” reveals a voluminous literature, though much of what has been published to date is based on technologies that are rapidly becoming obsolete. The technological limitations of previous techniques, including the transmission of static digital images and dynamic streaming images, have limited telecytology to minor niches. The primary problem with these technologies is that the remote viewer can only see a small fraction of the material on the original slides, introducing the possibility of diagnostic error based not only on image quality but also on image selection. Remote robotic microscopy offers one possible solution to this problem, but to date has found limited acceptance, principally attributable to slow operating times. Whole slide imaging seems to be a much more promising solution, though cytology-specific literature regarding its use is still scant. The advent of whole slide imaging opens up new possibilities for telecytology by enabling high-quality images of entire cytology specimens to be available to anyone, anywhere via the Internet. Although challenges remain, especially with regard to capturing the full microscopy experience including multiple planes of focus and sharp high-powered images, rapidly advancing technology promises to overcome these limitations. Increasing application of whole slide imaging technology in surgical pathology will undoubtedly also increase its application to cytology due to the increasing affordability and practicality of the equipment as it serves a larger number of useful roles within a pathology department. The current and expanding applications of telecytology for clinical practice, education, quality assurance, and testing will be reviewed. PMID:22276242

  8. Getting People Involved: The Benefit of Intellectual Capital Management for Addressing HR Challenges

    ERIC Educational Resources Information Center

    Pook, Katja

    2011-01-01

    Purpose: This paper aims to explore the benefits of intellectual capital assessment for facing current challenges of human resources work and organizational development. Design/methodology/approach: The paper takes findings of studies on challenges in HR work and maps them with features of intellectual capital assessment methods. It is thus a…

  9. The Benefits and Challenges of Multiple Health Behavior Change in Research and in Practice

    PubMed Central

    Prochaska, Judith J.; Nigg, Claudio R.; Spring, Bonnie; Velicer, Wayne F.; Prochaska, James O.

    2009-01-01

    Objective The major chronic diseases are caused by multiple risks, yet the science of multiple health behavior change (MHBC) is at an early stage, and factors that facilitate or impede scientists’ involvement in MHBC research are unknown. Benefits and challenges of MHBC interventions were investigated to strengthen researchers’ commitment and prepare them for challenges. Method An online anonymous survey was emailed to listservs of the Society of Behavioral Medicine between May 2006 and 2007. Respondents (N = 69) were 83% female; 94% held a doctoral degree; 64% were psychologists, 24% were in public health; 83% targeted MHBC in their work. Results A sample majority rated 23 of the 24 benefits, but only 1 of 31 challenge items, as very-to-extremely important. Those engaged in MHBC rated the total benefits significantly higher than respondents focused on single behaviors, F(1,69) = 4.21, p<.05, and rated the benefits significantly higher than the challenges: paired t(57) = 7.50, p<.001. The two groups did not differ in ratings of challenges. Conclusion It appears individuals focused solely on single behaviors do not fully appreciate the benefits that impress MHBC researchers; it is not that substantial barriers are holding them back. Benefits of MHBC interventions need emphasizing more broadly to advance this research area. PMID:19948184

  10. Hydrogen as a transportation fuel: Costs and benefits

    SciTech Connect

    Berry, G.D.

    1996-03-01

    Hydrogen fuel and vehicles are assessed and compared to other alternative fuels and vehicles. The cost, efficiency, and emissions of hydrogen storage, delivery, and use in hybrid-electric vehicles (HEVs) are estimated. Hydrogen made thermochemically from natural gas and electrolytically from a range of electricity mixes is examined. Hydrogen produced at central plants and delivered by truck is compared to hydrogen produced on-site at filling stations, fleet refueling centers, and residences. The impacts of hydrogen HEVs, fueled using these pathways, are compared to ultra-low emissions gasoline internal-combustion-engine vehicles (ICEVs), advanced battery-powered electric vehicles (BPEVs), and HEVs using gasoline or natural gas.

  11. Landing on empty: estimating the benefits from reducing fuel uplift in US Civil Aviation

    NASA Astrophysics Data System (ADS)

    Ryerson, Megan S.; Hansen, Mark; Hao, Lu; Seelhorst, Michael

    2015-09-01

    Airlines and Air Navigation Service Providers are united in their goal to reduce fuel consumption. While changes to flight operations and technology investments are the focus of a number of studies, our study is among the first to investigate an untapped source of aviation fuel consumption: excess contingency fuel loading. Given the downside risk of fuel exhaustion of diverting to an alternate airport, airline dispatchers may load excess fuel onto an aircraft. Such conservatism comes at a cost of consuming excess fuel, as fuel consumed is a function of, among other factors, aircraft weight. The aim of this paper is to quantify, on a per-flight basis, the fuel burned due to carrying fuel beyond what is needed for foreseeable contingencies, and thereby motivate research, federal guidance, and investments that allow airline dispatchers to reduce fuel uplift while maintaining near zero risks of fuel exhaustion. We merge large publicly available aviation and weather databases with a detailed dataset from a major US airline. Upon estimating factors that capture the quantity fuel consumed due to carrying a pound of weight for a range of aircraft types, we calculate the cost and greenhouse gas emissions from carrying unused fuel on arrival and additional contingency fuel above a conservative buffer for foreseeable contingencies. We establish that the major US carrier does indeed load fuel conservatively. We find that 4.48% of the fuel consumed by an average flight is due to carrying unused fuel and 1.04% of the fuel consumed by an average flight is due to carrying additional contingency fuel above a reasonable buffer. We find that simple changes in flight dispatching that maintain a statistically minimal risk of fuel exhaustion could result in yearly savings of 338 million lbs of CO2, the equivalent to the fuel consumed from 4760 flights on midsized commercial aircraft. Moreover, policy changes regarding maximum fuel loads or investments that reduce uncertainty or increase

  12. Cochlear implantation among deaf children with additional disabilities: parental perceptions of benefits, challenges, and service provision.

    PubMed

    Zaidman-Zait, Anat; Curle, Deirdre; Jamieson, Janet R; Chia, Ruth; Kozak, Frederick K

    2015-01-01

    Although increasing numbers of children with additional disabilities are receiving cochlear implants (CIs), little is known about family perspectives of the benefits and the challenges of cochlear implantation in this pediatric population. This study examines perceptions among parents of deaf children with additional disabilities regarding satisfaction with service provision, benefits, and challenges of the CI process. This was a mixed-methods study, which included a survey and interviews. Twenty-three families of deaf children with additional disabilities participated in this study, and 17 of these parents participated in in-depth interviews regarding their child's experience with the CI, including benefits and challenges. Interviews were analyzed through inductive thematic analysis. Parent-perceived benefits of cochlear implantation included children's improved sound awareness, communication skills, and greater well-being compared to preimplantation status. However, the majority of families felt that they and their children were not receiving enough services. Major challenges included managing funding; coping with limited availability of specialized services, particularly in rural areas; and continuing concerns about the child's communication, social skills, and academic performance. Results suggest that children with additional disabilities benefit from CIs, but they and their families also face unique challenges that professionals should consider when working with these families. PMID:25225328

  13. Benefits of an Integrated Fuel Cycle on Repository Effective Capacity

    SciTech Connect

    Davidson, D.; Hunter, I.; Vinoche, R.; Clement, G.; Louvet, T.; Bruyere, J.

    2006-07-01

    Today, the Yucca Mountain repository is limited by legislation to a maximum capacity of 70,000 metric tons of initial heavy metal (MTiHM), of which 63,000 MTiHM is reserved for civilian nuclear used fuel. Various sources have estimated the 'real' or 'technical' capacity of Yucca Mountain could be around 125,000 MTiHM. Whatever the actual number is, it will be significantly less than the anticipated total volume of used fuel expected to be generated in the US by 2100. This paper briefly reviews the design constraints of the Yucca Mountain repository and shows the potential gains in capacity by early recycling of used fuel from US commercial reactors using an evolutionary COEX process (co-extraction of uranium and plutonium) design. To optimize the Yucca Mountain loading, two important constraints need to be addressed: heat load and physical volume. For heat load there is a long-term issue with actinides (primarily plutonium and americium) and a short-term issue with fission products (primarily cesium and strontium). We present a new way to increase the capacity of Yucca Mountain by increasing the unit loading of the repository - early recycling approach. For the once-through option and the early recycling solution, drift loading factors are calculated, looking at both volume and heat. The resulting densification factor (ratio of drift loading factor of treatment high level waste residues to used fuel) is 4 using COEX technology. In simple terms, the total length of Yucca Mountain tunnels needed to dispose of 63,000 MTiHM of used fuel (legal limit) could be used to dispose of the residues from the treatment of 252,000 MTiHM of used fuel. (authors)

  14. CHALLENGES AND BENEFITS OF CONDUCTING ENVIRONMENTAL JUSTICE RESEARCH IN A SCHOOL SETTING

    PubMed Central

    GUIDRY, VIRGINIA T.; LOWMAN, AMY; HALL, DEVON; BARON, DOTHULA; WING, STEVE

    2015-01-01

    Environmental justice (EJ) research requires attention to consequences for research participants beyond those typically considered by institutional review boards. The imbalance of power between impacted communities and those who create and regulate pollution creates challenges for participation, yet research can also benefit those involved. Our community-academic partnership designed the Rural Air Pollutants and Children's Health (RAPCH) study to provide positive impacts while measuring health effects at three low-resource public middle schools near concentrated animal feeding operations (CAFOs) in North Carolina. We evaluated perceived benefits and challenges of study involvement by interviewing school staff and community liaisons who facilitated data collection. Reported benefits included enhancement of students’ academic environment and increased community environmental awareness; challenges were associated mainly with some participants’ immaturity. Leadership from a strong community-based organization was crucial to recruitment, yet our approach entailed minimal focus on EJ, which may have limited opportunities for community education or organizing for environmental health. PMID:25085828

  15. Fuel Ethanol Coproducts – Growing Challenges and Opportunities for Fueling America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a nation, we face many challenges, including growing population, industrialization, as well as material and energy consumption. Coupled with these is an increasing reliance on fossil fuels, whose markets have historically been quite volatile, the energy security needs of North America continue t...

  16. Benefits of modern refinery information systems for manufacturing cleaner fuels

    SciTech Connect

    Latour, P.R.

    1995-12-31

    Revolutionary changes in quality specifications (number, complexity, uncertainty, economic sensitivity) for reformulated gasolines (RFG) and low-sulfur diesels (LSD) are being addressed by powerful, new, computer integrated manufacturing technology for Refinery Information Systems and Advanced Process Control (RIS/APC). This paper shows how the five active RIS/APC functions -- performance measurement, optimization, scheduling, control and integration -- are used to manufacture new, clean fuels competitively. With current industry spending for this field averaging 2 to 3 cents/bbl crude, many refineries can capture 50 to 100 cents/bbl if the technology is properly employed and sustained throughout refining operations, organizations, and businesses.

  17. Stakeholder Perceptions of the Positive Benefits and Critical Challenges Involved in Student Service-Learning Experiences

    ERIC Educational Resources Information Center

    Hohenthal, K. Darcy

    2010-01-01

    The Bolman and Deal (2003) Four-Frame Model was adapted in this qualitative phenomenological research study to describe how stakeholders experience student service-learning. The study presents how students perceive the positive benefits and critical challenges encountered in their service-learning experience; how professors perceive the positive…

  18. The Invisible Student: Benefits and Challenges of Part-Time Doctoral Studies

    ERIC Educational Resources Information Center

    Bates, Peter; Goff, Lori

    2012-01-01

    This autoethnographic study explores the experiences of two part-time doctoral students as we document our journey of balancing our multiple competing roles. As we reflected and consulted the literature, we began to identify many benefits and challenges that part-time candidature brings to students, universities and employers. Through our…

  19. Benefits and Challenges of a Teacher Cluster in South Africa: The Case of Sizabantwana

    ERIC Educational Resources Information Center

    Mitchell, Carol; Jonker, David

    2013-01-01

    This article explores teacher clusters as possible mechanisms for teacher development in dealing with a number of the difficulties facing education in the South African context. It describes the benefits and challenges experienced by primary school teachers who are involved in a self-sustaining teacher cluster (development and support group). This…

  20. Enhancing Geographic Education: Challenges and Benefits of Collaboration with Outside Agencies.

    ERIC Educational Resources Information Center

    Maier, Joan N.; Jones, Douglas Deane

    1999-01-01

    Argues that an avenue for enhancing geography education lies in collaboration between teacher educators and government agencies. Describes a cooperative program between the University of Houston-Clear Lake (Texas) and NASA's Johnson Space Center. Discusses challenges in creating the program, the nature of the program, and benefits from…

  1. The Twenty-First Century Multiple Generation Workforce: Overlaps and Differences but Also Challenges and Benefits

    ERIC Educational Resources Information Center

    Helyer, Ruth; Lee, Dionne

    2012-01-01

    Purpose: The purpose of this paper is to explore the issues around a multiple generational workforce and more specifically, the challenges and benefits for education providers and employers. Design/methodology/approach: Reviewing research papers, analysing academic texts, interrogating market intelligence and contextualising case studies, the…

  2. Implementing Portfolio-Based Language Assessment in LINC Programs: Benefits and Challenges

    ERIC Educational Resources Information Center

    Ripley, Daniel

    2012-01-01

    Although earlier research has examined the potential of portfolios as assessment tools, research on the use of portfolios in the context of second-language education in Canada has been limited. The goal of this study was to explore the benefits and challenges of implementing a portfolio-based language assessment (PBLA) model in Language…

  3. Collaborative Research between Community Development Practitioners and University Based Researchers: Challenges and Benefits.

    ERIC Educational Resources Information Center

    Warner, Mildred E.; Hinrichs, Clare; Schneyer, Judith; Joyce, Lucy

    A research project identified the challenges and benefits of collaborative research between extension agents and researchers. Its methodology was a critical review of the collaborative research approach used in a case study examining the usefulness of social capital in promoting rural landscape sustainability in two counties in the Hudson River…

  4. Supporting Young Children's Vocabulary Growth: The Challenges, the Benefits, and Evidence-Based Strategies

    ERIC Educational Resources Information Center

    Jalongo, Mary Renck; Sobolak, Michelle J.

    2011-01-01

    The complexity of words makes vocabulary development a multi-faceted process that presents challenges to early childhood educators, offers benefits to young learners, and must be supported through evidence-based strategies. All students, regardless of socio-economic status or background, need to make significant gains in receptive and expressive…

  5. The Benefits and Challenges of Culturally Responsive EFL Critical Literature Circles

    ERIC Educational Resources Information Center

    Fredricks, Lori

    2012-01-01

    Though some research has shown what applying a culturally relevant framework entails in an American context, and occasionally in an EFL setting, there is still too little research on how students respond to critical, culturally responsive pedagogy. More insight is needed into the specific challenges and benefits of critical approaches in diverse…

  6. Scheduling Recess before Lunch: Exploring the Benefits and Challenges in Montana Schools

    ERIC Educational Resources Information Center

    Bark, Katie; Stenberg, Molly; Sutherland, Shelly; Hayes, Dayle

    2010-01-01

    Purpose/Objectives: The purpose of the "Montana Recess Before Lunch Survey" was to explore benefits, challenges, and factors associated with successful implementation of Recess Before Lunch (RBL), from the perspective of school principals. Methods: An online written questionnaire was distributed to all (N = 661) Montana elementary and middle…

  7. Benefits, Challenges, and Perceptions of the Multiple Article Dissertation Format in Instructional Technology

    ERIC Educational Resources Information Center

    Thomas, Rebecca Arlene; West, Richard E.; Rich, Peter

    2016-01-01

    This study used survey data to investigate the benefits, challenges, perceptions, and current practices of the multiple article dissertation format in instructional technology. Online surveys were sent to current students, alumni, faculty, and department representatives of instructional technology programs, and data were analysed using qualitative…

  8. Cochlear Implantation among Deaf Children with Additional Disabilities: Parental Perceptions of Benefits, Challenges, and Service Provision

    ERIC Educational Resources Information Center

    Zaidman-Zait, Anat; Curle, Deirdre; Jamieson, Janet R.; Chia, Ruth; Kozak, Frederick K.

    2015-01-01

    Although increasing numbers of children with additional disabilities are receiving cochlear implants (CIs), little is known about family perspectives of the benefits and the challenges of cochlear implantation in this pediatric population. This study examines perceptions among parents of deaf children with additional disabilities regarding…

  9. Military Veterans Face Challenges in Accessing Educational Benefits at Florida Community Colleges

    ERIC Educational Resources Information Center

    Spiro, Rivka; Hill, Robert

    2010-01-01

    Florida's community colleges are seeing an influx of students who face unique challenges. They are the men and women who served in the military after the attacks of September 11, 2001, and who are now attending college on the new Post-9/11 GI Bill, with its greatly enhanced educational benefits, and on the expanded, old Montgomery GI Bill, which…

  10. System-agnostic clinical decision support services: benefits and challenges for scalable decision support.

    PubMed

    Kawamoto, Kensaku; Del Fiol, Guilherme; Orton, Charles; Lobach, David F

    2010-01-01

    System-agnostic clinical decision support (CDS) services provide patient evaluation capabilities that are independent of specific CDS systems and system implementation contexts. While such system-agnostic CDS services hold great potential for facilitating the widespread implementation of CDS systems, little has been described regarding the benefits and challenges of their use. In this manuscript, the authors address this need by describing potential benefits and challenges of using a system-agnostic CDS service. This analysis is based on the authors' formal assessments of, and practical experiences with, various approaches to developing, implementing, and maintaining CDS capabilities. In particular, the analysis draws on the authors' experience developing and leveraging a system-agnostic CDS Web service known as SEBASTIAN. A primary potential benefit of using a system-agnostic CDS service is the relative ease and flexibility with which the service can be leveraged to implement CDS capabilities across applications and care settings. Other important potential benefits include facilitation of centralized knowledge management and knowledge sharing; the potential to support multiple underlying knowledge representations and knowledge resources through a common service interface; improved simplicity and componentization; easier testing and validation; and the enabling of distributed CDS system development. Conversely, important potential challenges include the increased effort required to develop knowledge resources capable of being used in many contexts and the critical need to standardize the service interface. Despite these challenges, our experiences to date indicate that the benefits of using a system-agnostic CDS service generally outweigh the challenges of using this approach to implementing and maintaining CDS systems. PMID:21603281

  11. Bioconversion of natural gas to liquid fuel: Opportunities and challenges

    SciTech Connect

    Fei, Q; Guarnieri, MT; Tao, L; Laurens, LML; Dowe, N; Pienkos, PT

    2014-05-01

    Natural gas is a mixture of low molecular weight hydrocarbon gases that can be generated from either fossil or anthropogenic resources. Although natural gas is used as a transportation fuel, constraints in storage, relatively low energy content (MJ/L), and delivery have limited widespread adoption. Advanced utilization of natural gas has been explored for biofuel production by microorganisms. In recent years, the aerobic bioconversion of natural gas (or primarily the methane content of natural gas) into liquid fuels (Bio-GTL) by biocatalysts (methanotrophs) has gained increasing attention as a promising alternative for drop-in biofuel production. Methanotrophic bacteria are capable of converting methane into microbial lipids, which can in turn be converted into renewable diesel via a hydrotreating process. In this paper, biodiversity, catalytic properties and key enzymes and pathways of these microbes are summarized. Bioprocess technologies are discussed based upon existing literature, including cultivation conditions, fermentation modes, bioreactor design, and lipid extraction and upgrading. This review also outlines the potential of Bio-GTL using methane as an alternative carbon source as well as the major challenges and future research needs of microbial lipid accumulation derived from methane, key performance index, and techno-economic analysis. An analysis of raw material costs suggests that methane-derived diesel fuel has the potential to be competitive with petroleum-derived diesel. (C) 2014 The Authors. Published by Elsevier Inc.

  12. Bioconversion of Natural Gas to Liquid Fuel. Opportunities and Challenges

    SciTech Connect

    Fei, Qiang; Guarnieri, Michael T.; Tao, Ling; Laurens, Lieve M. L.; Dowe, Nancy; Pienkos, Philip T.

    2014-05-01

    Natural gas is a mixture of low molecular weight hydrocarbon gases that can be generated from either fossil or anthropogenic resources. Although natural gas is used as a transportation fuel, constraints in storage, relatively low energy content (MJ/L), and delivery have limited widespread adoption. Advanced utilization of natural gas has been explored for biofuel production by microorganisms. In recent years, the aerobic bioconversion of natural gas (or primarily the methane content of natural gas) into liquid fuels (Bio-GTL) by biocatalysts (methanotrophs) has gained increasing attention as a promising alternative for drop-in biofuel production. Moreover, methanotrophic bacteria are capable of converting methane into microbial lipids, which can in turn be converted into renewable diesel via a hydrotreating process. In this paper, biodiversity, catalytic properties and key enzymes and pathways of these microbes are summarized. Bioprocess technologies are discussed based upon existing literature, including cultivation conditions, fermentation modes, bioreactor design, and lipid extraction and upgrading. Our review also outlines the potential of Bio-GTL using methane as an alternative carbon source as well as the major challenges and future research needs of microbial lipid accumulation derived from methane, key performance index, and techno-economic analysis. An analysis of raw material costs suggests that methane-derived diesel fuel has the potential to be competitive with petroleum-derived diesel.

  13. Fuel switching from wood to LPG can benefit the environment

    SciTech Connect

    Nautiyal, Sunil Kaechele, Harald

    2008-11-15

    The Himalaya in India is one of the world's biodiversity hotspots. Various scientific studies have reported and proven that many factors are responsible for the tremendous decline of the Himalayan forests. Extraction of wood biomass from the forests for fuel is one of the factors, as rural households rely entirely on this for their domestic energy. Efforts continue for both conservation and development of the Himalayan forests and landscape. It has been reported that people are still looking for more viable solutions that could help them to improve their lifestyle as well as facilitate ecosystem conservation and preservation of existing biodiversity. In this direction, we have documented the potential of the introduction of liquefied petroleum gas (LPG), which is one of the solutions that have been offered to the local people as a substitute for woodfuel to help meet their domestic energy demand. The results of the current study found dramatic change in per capita woodfuel consumption in the last two decades in the villages where people are using LPG. The outcome showed that woodfuel consumption had been about 475 kg per capita per year in the region, but after introduction of LPG, this was reduced to 285 kg per capita per year in 1990-1995, and was further reduced to 46 kg per capita per year in 2000-2005. Besides improving the living conditions of the local people, this transformation has had great environmental consequences. Empirical evidence shows that this new paradigm shift is having positive external effects on the surrounding forests. Consequently, we have observed a high density of tree saplings and seedlings in adjacent forests, which serves as an assessment indicator of forest health. With the help of the current study, we propose that when thinking about a top-down approach to conservation, better solutions, which are often ignored, should be offered to local people.

  14. The Benefits and Challenges of Preconsent in a Multisite, Pediatric Sickle Cell Intervention Trial.

    PubMed

    Nimmer, Mark; Czachor, Jason; Turner, Laura; Thomas, Bobbe; Woodford, Ashley L; Carpenter, Karli; Gonzalez, Victor; Liem, Robert I; Ellison, Angela; Casper, T Charles; Brousseau, David C

    2016-09-01

    Enrollment of patients in sickle cell intervention trials has been challenging due to difficulty in obtaining consent from a legal guardian and lack of collaboration between emergency medicine and hematology. We utilized education and preconsent in a pediatric multisite sickle cell intervention trial to overcome these challenges. Overall, 48 patients were enrolled after being preconsented. Variable Institutional Review Board policies related to preconsent validity and its allowable duration decreased the advantages of preconsent at some sites. The utility of preconsent for future intervention trials largely depends on local Institutional Review Board policies. Preeducation may also benefit the consent process, regardless of site differences. PMID:27081930

  15. Benefits of two mitigation strategies for container vessels: cleaner engines and cleaner fuels.

    PubMed

    Khan, M Yusuf; Giordano, Michael; Gutierrez, James; Welch, William A; Asa-Awuku, A; Miller, J Wayne; Cocker, David R

    2012-05-01

    Emissions from ocean-going vessels (OGVs) are a significant health concern for people near port communities. This paper reports the emission benefits for two mitigation strategies, cleaner engines and cleaner fuels, for a 2010 container vessel. In-use emissions were measured following International Organization for Standardization (ISO) protocols. The overall in-use nitrogen oxide (NO(x)) emission factor was 16.1 ± 0.1 gkW(-1) h(-1), lower than the Tier 1 certification (17 gkW(-1) h(-1)) and significantly lower than the benchmark value of 18.7 gkW(-1) h(-1) commonly used for estimating emission inventories. The in-use particulate matter (PM(2.5)) emission was 1.42 ± 0.04 gkW(-1) h(-1) for heavy fuel oil (HFO) containing 2.51 wt % sulfur. Unimodal (∼30 nm) and bimodal (∼35 nm; ∼75 nm) particle number size distributions (NSDs) were observed when the vessel operated on marine gas oil (MGO) and HFO, respectively. First-time emission measurements during fuel switching (required 24 nautical miles from coastline) showed that concentrations of sulfur dioxide (SO(2)) and particle NSD took ∼55 min to reach steady-state when switching from MGO to HFO and ∼84 min in the opposite direction. Therefore, if OGVs commence fuel change at the regulated boundary, then vessels can travel up to 90% of the distance to the port before steady-state values are re-established. The transient behavior follows a classic, nonlinear mixing function driven by the amount of fuel in day tank and the fuel consumption rate. Hence, to achieve the maximum benefits from a fuel change regulation, fuel switch boundary should be further increased to provide the intended benefits for the people living near the ports. PMID:22468877

  16. Challenge for lowering concentration polarization in solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Shimada, Hiroyuki; Suzuki, Toshio; Yamaguchi, Toshiaki; Sumi, Hirofumi; Hamamoto, Koichi; Fujishiro, Yoshinobu

    2016-01-01

    In the scope of electrochemical phenomena, concentration polarization at electrodes is theoretically inevitable, and lowering the concentration overpotential to improve the performance of electrochemical cells has been a continuing challenge. Electrodes with highly controlled microstructure, i.e., high porosity and uniform large pores are therefore essential to achieve high performance electrochemical cells. In this study, state-of-the-art technology for controlling the microstructure of electrodes has been developed for realizing high performance support electrodes of solid oxide fuel cells (SOFCs). The key is controlling the porosity and pore size distribution to improve gas diffusion, while maintaining the integrity of the electrolyte and the structural strength of actual sized electrode supports needed for the target application. Planar anode-supported SOFCs developed in this study realize 5 μm thick dense electrolyte (yttria-stabilized zirconia: YSZ) and the anode substrate (Ni-YSZ) of 53.6 vol.% porosity with a large median pore diameter of 0.911 μm. Electrochemical measurements reveal that the performance of the anode-supported SOFCs improves with increasing anode porosity. This Ni-YSZ anode minimizes the concentration polarization, resulting in a maximum power density of 3.09 W cm-2 at 800 °C using humidified hydrogen fuel without any electrode functional layers.

  17. Future nuclear fuel cycles: Prospect and challenges for actinide recycling

    NASA Astrophysics Data System (ADS)

    Warin, Dominique

    2010-03-01

    The global energy context pleads in favour of a sustainable development of nuclear energy since the demand for energy will likely increase, whereas resources will tend to get scarcer and the prospect of global warming will drive down the consumption of fossil fuel. In this context, nuclear power has the worldwide potential to curtail the dependence on fossil fuels and thereby to reduce the amount of greenhouse gas emissions while promoting energy independence. How we deal with nuclear radioactive waste is crucial in this context. In France, the public's concern regarding the long-term waste management made the French Governments to prepare and pass the 1991 and 2006 Acts, requesting in particular the study of applicable solutions for still minimizing the quantity and the hazardousness of final waste. This necessitates High Active Long Life element (such as the Minor Actinides MA) recycling, since the results of fuel cycle R&D could significantly change the challenges for the storage of nuclear waste. HALL recycling can reduce the heat load and the half-life of most of the waste to be buried to a couple of hundred years, overcoming the concerns of the public related to the long-life of the waste and thus aiding the "burying approach" in securing a "broadly agreed political consensus" of waste disposal in a geological repository. This paper presents an overview of the recent R and D results obtained at the CEA Atalante facility on innovative actinide partitioning hydrometallurgical processes. For americium and curium partitioning, these results concern improvements and possible simplifications of the Diamex-Sanex process, whose technical feasibility was already demonstrated in 2005. Results on the first tests of the Ganex process (grouped actinide separation for homogeneous recycling) are also discussed. In the coming years, next steps will involve both better in-depth understanding of the basis of these actinide partitioning processes and, for the new promising

  18. Small group learning: graduate health students' views of challenges and benefits.

    PubMed

    Jackson, Debra; Hickman, Louise D; Power, Tamara; Disler, Rebecca; Potgieter, Ingrid; Deek, Hiba; Davidson, Patricia M

    2014-07-19

    Abstract Background: For health care professionals, particularly nurses, the need to work productively and efficiently in small groups is a crucial skill required to meet the challenges of the contemporary health-care environment. Small group work is an educational technique that is used extensively in nurse education. The advantage of group work includes facilitation of deep, active and collaborative learning. However, small group work can be problematic and present challenges for students. Many of the challenges occur because group work necessitates the coming together of collections of individuals, each with their own personalities and sets of experiences. Aim: This study aimed to identify challenges and benefits associated with small group work and to explore options for retaining the positive aspects of group work while reducing or eliminating the aspects the students experienced as negative. Method: Online survey; thematic analysis. Results: Over all, students experienced a range of challenges that necessitated the development of problem-solving strategies. However, they were able to elucidate some enjoyable and positive aspects of group work. Implications for teaching and learning are drawn from this study. Conclusion: The ability to work effectively in small groups and teams is essential for all health care workers in the contemporary health environment. Findings of this study highlight the need for educators to explore novel and effective ways in which to engage nurses in group work. PMID:25041385

  19. Early access programs: Benefits, challenges, and key considerations for successful implementation.

    PubMed

    Patil, Sanjaykumar

    2016-01-01

    Early access programs, (EAPs) are adopted by an increasing number of pharma companies due to several benefits offered by these programs. EAPs offer ethical, compliant, and controlled mechanisms of access to investigational drugs outside of the clinical trial space and before the commercial launch of the drug, to patients with life-threatening diseases having no treatment options available. In addition to the development of positive relationships with key opinion leaders (KOL), patients, advocacy groups and regulators, the data captured from the implementation of EAPs supports in the formulation of global commercialization strategies. This white paper outlines various circumstances to be considered for the implementation of EAPs named patient programs, the regulatory landscape, the benefits and challenges associated with implementing these programs and the key considerations for their successful implementation. PMID:26955570

  20. Early access programs: Benefits, challenges, and key considerations for successful implementation

    PubMed Central

    Patil, Sanjaykumar

    2016-01-01

    Early access programs, (EAPs) are adopted by an increasing number of pharma companies due to several benefits offered by these programs. EAPs offer ethical, compliant, and controlled mechanisms of access to investigational drugs outside of the clinical trial space and before the commercial launch of the drug, to patients with life-threatening diseases having no treatment options available. In addition to the development of positive relationships with key opinion leaders (KOL), patients, advocacy groups and regulators, the data captured from the implementation of EAPs supports in the formulation of global commercialization strategies. This white paper outlines various circumstances to be considered for the implementation of EAPs named patient programs, the regulatory landscape, the benefits and challenges associated with implementing these programs and the key considerations for their successful implementation. PMID:26955570

  1. Collecting Patient Data from Sensor-Based Systems: Benefits and Challenges.

    PubMed

    Gashgari, Horeya; Attallah, Nora; Al Muallem, Yahya; Al Dogether, Majed; Al Moammary, Eman; Almeshari, Meshari; Househ, Mowafa

    2016-01-01

    The purpose of this study is to review the literature on the use of sensor-based technology in the collection of healthcare data from health consumers and/or patients. A literature search was conducted in November 2015 through the PubMed database. A total of 4,800 articles were retrieved using the terms "sensors-based systems in healthcare" and "sensor monitoring in healthcare". After scanning the articles, and applying the inclusion and exclusion criteria, 10 articles were found relevant and included in the review. This study highlights the benefits and challenges when using sensor-based systems in the collection of health consumer and/or patient information. Some of the benefits in the collection of data are remote monitoring features and the real-time data collection features. Some of the challenges are privacy, security, and sensitivity to technology issues. Future work should evaluate the quality of the research evidence on sensor-based technologies and how such information impacts quality of care. PMID:27350461

  2. Energy and emission benefits of alternative transportation liquid fuels derived from switchgrass: a fuel life cycle assessment.

    PubMed

    Wu, May; Wu, Ye; Wang, Michael

    2006-01-01

    We conducted a mobility chains, or well-to-wheels (WTW), analysis to assess the energy and emission benefits of cellulosic biomass for the U.S. transportation sector in the years 2015-2030. We estimated the life-cycle energy consumption and emissions associated with biofuel production and use in light-duty vehicle (LDV) technologies by using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model. Analysis of biofuel production was based on ASPEN Plus model simulation of an advanced fermentation process to produce fuel ethanol/protein, a thermochemical process to produce Fischer-Tropsch diesel (FTD) and dimethyl ether (DME), and a combined heat and power plant to co-produce steam and electricity. Our study revealed that cellulosic biofuels as E85 (mixture of 85% ethanol and 15% gasoline by volume), FTD, and DME offer substantial savings in petroleum (66-93%) and fossil energy (65-88%) consumption on a per-mile basis. Decreased fossil fuel use translates to 82-87% reductions in greenhouse gas emissions across all unblended cellulosic biofuels. In urban areas, our study shows net reductions for almost all criteria pollutants, with the exception of carbon monoxide (unchanged), for each of the biofuel production option examined. Conventional and hybrid electric vehicles, when fueled with E85, could reduce total sulfur oxide (SO(x)) emissions to 39-43% of those generated by vehicles fueled with gasoline. By using bio-FTD and bio-DME in place of diesel, SO(x) emissions are reduced to 46-58% of those generated by diesel-fueled vehicles. Six different fuel production options were compared. This study strongly suggests that integrated heat and power co-generation by means of gas turbine combined cycle is a crucial factor in the energy savings and emission reductions. PMID:16889378

  3. Early Child Development and Nutrition: A Review of the Benefits and Challenges of Implementing Integrated Interventions.

    PubMed

    Hurley, Kristen M; Yousafzai, Aisha K; Lopez-Boo, Florencia

    2016-03-01

    Poor nutrition (substandard diet quantity and/or quality resulting in under- or overnutrition) and the lack of early learning opportunities contribute to the loss of developmental potential and life-long health and economic disparities among millions of children aged <5 y. Single-sector interventions representing either early child development (ECD) or nutrition have been linked to positive child development and/or nutritional status, and recommendations currently advocate for the development and testing of integrated interventions. We reviewed the theoretical and practical benefits and challenges of implementing integrated nutrition and ECD interventions along with the evidence for best practice and benefit-cost and concluded that the strong theoretical rationale for integration is more nuanced than the questions that the published empirical evidence have addressed. For example, further research is needed to 1) answer questions related to how integrated messaging influences caregiver characteristics such as well-being, knowledge, and behavior and how these influence early child nutrition and development outcomes; 2) understand population and nutritional contexts in which integrated interventions are beneficial; and 3) explore how varying implementation processes influence the efficacy, uptake, and cost-benefit of integrated nutrition and ECD interventions. PMID:26980819

  4. Timely Diagnosis for Alzheimer’s Disease: A Literature Review on Benefits and Challenges

    PubMed Central

    Dubois, Bruno; Padovani, Alessandro; Scheltens, Philip; Rossi, Andrea; Dell’Agnello, Grazia

    2015-01-01

    Background: Timely diagnosis of Alzheimer’s disease (AD) refers to a diagnosis at the stage when patients come to the attention of clinicians because of concerns about changes in cognition, behavior, or functioning and can be still free of dementia and functionally independent. Objectives: To comprehensively review existing scientific evidence on the benefits and potential challenges of making a timely diagnosis of AD. Methods: Relevant studies were identified by searching electronic databases (Medline, Embase) and bibliographies for studies published in English between 1 January 2000 and 2 June 2014 on the consequences of a timely diagnosis of AD. Results: Nine studies were identified that investigated the consequences of diagnosing AD at the initial stages; none were specifically focused on prodromal AD. A timely diagnosis potentially offers the opportunities of early intervention, implementation of coordinated care plans, better management of symptoms, patient safety, cost savings, and postponement of institutionalization. Barriers to making a timely diagnosis include stigma, suicide risk, lack of training, diagnostic uncertainty, shortage of specialized diagnostic services, and the reluctance of healthcare providers to make a diagnosis when no effective disease-modifying options are available. Conclusions: Despite its potential benefits, few published studies have explored the advantages or risks of a timely diagnosis of AD. In light of the cultural shift toward diagnosis at the initial stage of the disease continuum, when the patient does not yet have dementia, more investigations are needed to evaluate the benefits and address the barriers that may impede making a timely AD diagnosis. PMID:26484931

  5. Multinational medical support to operations: challenges, benefits and recommendations for the future.

    PubMed

    Cordell, R F

    2012-03-01

    This paper considers the strategic aspects of medical support to military operations as delivered through multi-national collaboration. The military medical services are in essence a people organisation; the purpose of the organisation is primarily to support the people engaged in military operations, and also the people providing healthcare to them. Increasingly, supporting the latter also includes preparation for the ethical dilemmas that they will face. Providing health advice and healthcare on operations is now usually undertaken on a multinational basis, in order to generate sufficient medical capacity to meet the requirement with assets of the appropriate (and NATO mandated) capability. This will be an enduring feature, particularly in light of increasing costs of providing high quality healthcare and the operational and logistic challenges of delivering this capability in adverse environments, and in the context of medical personnel being a limited resource. The key to overcoming the challenges, often the result of the "people issues" such as cultural differences, is to recognise the value that the inherent diversity of multinational healthcare provision brings. The benefit is realised through sharing best practice, and the lessons from challenges met, as well as through burden sharing, and to understand that challenges are most commonly the result of misunderstandings, such as those inherent in language differences. The advice for those bringing a multinational team together includes considering the implications of culture (noting differences in national and military perspectives, and in medical processes such as clinical governance), to ensure effective communication, and to utilise feedback to confirm understanding. It is important not to prejudge or denigrate others. Share information and knowledge, provide positive reinforcement when things go well, and recognise that there will inevitably be challenges and use these as an opportunity to learn. Above

  6. Increasing Diversity in the Sciences: a Partial Solution to the Challenge and the Benefits it Produces

    NASA Astrophysics Data System (ADS)

    Givan, A. V.

    2009-12-01

    Science is supposed to be about talent devoid of the bias’ and judgments generated by background, gender, ethnicity or any culturally determined discriminators. The scientific, academic, corporate and government communities have a vested interest in developing models, practices and policies that significantly increase the number of U.S. graduates in scientific disciplines. Additionally, it is crucial that these graduates possess the essential competencies and creative problem solving skills to compete in the current global economy. The stakeholders (corporations, researchers, educational practitioners, policymakers and funders) who have the common goal of producing highly qualified scientists must commit to collaborate in developing innovative strategies and solutions to this complex challenge. Volumes of research data from a variety of sources such the social and cognitive sciences, educational psychology, National Science Foundation and non-profit groups have been and are available for use enabling us to rise to the challenge we have been charged with, and are responsible for the outcome. A proposed solution to part of the challenge and discussion of the impacts of increasing diversity in science will be discussed in this paper. The paper will address one element of the issue - strategies for the recruitment and retention of under-represented groups in science focusing on the historical and current culture, climate and barriers encountered by minorities as they progress through the educational system and career pathways. The paper will examine the benefits of diversity to the individual and society as a whole.

  7. Challenges for fuel cells as stationary power resource in the evolving energy enterprise

    NASA Astrophysics Data System (ADS)

    Rastler, Dan

    The primary market challenges for fuel cells as stationary power resources in evolving energy markets are reviewed. Fuel cell power systems have significant barriers to overcome in their anticipated role as decentralized energy power systems. Market segments for fuel cells include combined heat and power; low-cost energy, premium power; peak shaving; and load management and grid support. Understanding the role and fit of fuel cell systems in evolving energy markets and the highest value applications are a major challenge for developers and government funding organizations. The most likely adopters of fuel cell systems and the challenges facing each adopter in the target market segment are reviewed. Adopters include generation companies, utility distribution companies, retail energy service providers and end-users. Key challenges include: overcoming technology risk; achieving retail competitiveness; understanding high value markets and end-user needs; distribution and service channels; regulatory policy issues; and the integration of these decentralized resources within the electrical distribution system.

  8. Advanced nuclear fuel cycles - Main challenges and strategic choices

    SciTech Connect

    Le Biez, V.; Machiels, A.; Sowder, A.

    2013-07-01

    A graphical conceptual model of the uranium fuel cycles has been developed to capture the present, anticipated, and potential (future) nuclear fuel cycle elements. The once-through cycle and plutonium recycle in fast reactors represent two basic approaches that bound classical options for nuclear fuel cycles. Chief among these other options are mono-recycling of plutonium in thermal reactors and recycling of minor actinides in fast reactors. Mono-recycling of plutonium in thermal reactors offers modest savings in natural uranium, provides an alternative approach for present-day interim management of used fuel, and offers a potential bridging technology to development and deployment of future fuel cycles. In addition to breeder reactors' obvious fuel sustainability advantages, recycling of minor actinides in fast reactors offers an attractive concept for long-term management of the wastes, but its ultimate value is uncertain in view of the added complexity in doing so,. Ultimately, there are no simple choices for nuclear fuel cycle options, as the selection of a fuel cycle option must reflect strategic criteria and priorities that vary with national policy and market perspectives. For example, fuel cycle decision-making driven primarily by national strategic interests will likely favor energy security or proliferation resistance issues, whereas decisions driven primarily by commercial or market influences will focus on economic competitiveness.

  9. Photovoltaics (PV) as an Eligible Measure in Residential PACE Programs: Benefits and Challenges (Fact Sheet)

    SciTech Connect

    Coughlin, J.

    2010-06-01

    Property Assessed Clean Energy (PACE) financing is one of several new financial models broadening access to clean energy by addressing the barrier of initial capital cost. The majority of the PACE programs in the market today include PV as an eligible measure. PV appeals to homeowners as a way to reduce utility bills, self-generate sustainable power, increase energy independence and demonstrate a commitment to the environment. If substantial state incentives for PV exist, PV projects can be economic under PACE, especially when partnered with good net metering policies. At the same time, PV is expensive relative to other eligible measures with a return on investment horizon that might exceed program targets. This fact sheet reviews the benefits and potential challenges of including PV in PACE programs.

  10. Dynamic Human Reliability Analysis: Benefits and Challenges of Simulating Human Performance

    SciTech Connect

    R. L. Boring

    2007-06-01

    To date, there has been considerable work on dynamic event trees and other areas related to dynamic probabilistic safety assessment (PSA). The counterpart to these efforts in human reliability analysis (HRA) has centered on the development of specific methods to account for the dynamic nature of human performance. In this paper, the author posits that the key to dynamic HRA is not in the development of specific methods but in the utilization of cognitive modeling and simulation to produce a framework of data that may be used in quantifying the likelihood of human error. This paper provides an overview of simulation approaches to HRA; reviews differences between first, second, and dynamic generation HRA; and outlines potential benefits and challenges of this approach.

  11. Long-term hand tele-rehabilitation on the PlayStation 3: benefits and challenges.

    PubMed

    Burdea, Grigore C; Jain, Abhishek; Rabin, Bryan; Pellosie, Richard; Golomb, Meredith

    2011-01-01

    Rehabilitation interventions for the hand have shown benefits for children with Hemiplegia due to cerebral palsy or traumatic brain injury. Longer interventions are facilitated if training is provided in the patient's home, due to easier access to care and reduced impact on school or work activities. Providing remote rehabilitation over lengthy periods of time has however its own challenges. This paper presents two pediatric patients with hemiplegia, who practiced virtual hand rehabilitation games using a modified PlayStation 3 and 5DT sensing gloves. Despite severe initial hand spasticity, and occasional technology shortcomings, the subjects practiced for about 14 months, and 6 months, respectively. Game performance data for the second patient is presented. Follow-up evaluations 14 months from the removal of the PlayStation 3 from the home of the child with cerebral palsy showed that the patient had good retention in terms of grasp strength, hand function and bone health. Challenges of long-term home tele-rehabilitation are also discussed. PMID:22254686

  12. Harmonisation of food labelling regulations in Southeast Asia: benefits, challenges and implications.

    PubMed

    Kasapila, William; Shaarani, Sharifudin Md

    2011-01-01

    In the globalised world of the 21st century, issues of food and nutrition labelling are of pre-eminent importance. Several international bodies, including the World Health Organisation and World Trade Organisation, are encouraging countries to harmonise their food and nutrition regulations with international standards, guidelines and recommendations such as those for Codex Alimentarius. Through harmonisation, these organisations envisage fewer barriers to trade and freer movement of food products between countries, which would open doors to new markets and opportunities for the food industry. In turn, increased food trade would enhance economic development and allow consumers a greater choice of products. Inevitably, however, embracing harmonisation brings along cost implications and challenges that have to be overcome. Moreover, the harmonisation process is complex and sporadic in light of the tasks that countries have to undertake; for example, updating legislation, strengthening administrative capabilities and establishing analytical laboratories. This review discusses the legislation and regulations that govern food and nutrition labelling in Southeast Asia, and highlights the discrepancies that exist in this regard, their origin and consequences. It also gives an account of the current status of harmonising labelling of pre-packaged foodstuffs in the region and explains the subsequent benefits, challenges and implications for governments, the food industry and consumers. PMID:21393103

  13. Social Media in the Dental School Environment, Part A: Benefits, Challenges, and Recommendations for Use.

    PubMed

    Spallek, Heiko; Turner, Sharon P; Donate-Bartfield, Evelyn; Chambers, David; McAndrew, Maureen; Zarkowski, Pamela; Karimbux, Nadeem

    2015-10-01

    Social media consist of powerful tools that impact not only communication but relationships among people, thus posing an inherent challenge to the traditional standards of who we are as dental educators and what we can expect of each other. This article examines how the world of social media has changed dental education. Its goal is to outline the complex issues that social media use presents for academic dental institutions and to examine these issues from personal, professional, and legal perspectives. After providing an update on social media, the article considers the advantages and risks associated with the use of social media at the interpersonal, professional, and institutional levels. Policies and legal issues of which academic dental institutions need to be aware from a compliance perspective are examined, along with considerations and resources needed to develop effective social media policies. The challenge facing dental educators is how to capitalize on the benefits that social media offer, while minimizing risks and complying with the various forms of legal constraint. PMID:26427774

  14. Benefits and Challenges of Delivering Tele-rehabilitation Services to Rural Veterans.

    PubMed

    Cary, Michael P; Spencer, Michelle; Carroll, Ansuya; Hand, Deborah H; Amis, Kristopher; Karan, Elizabeth; Cannon, Rebecca F; Morgan, Michelle S; Hoenig, Helen M

    2016-09-01

    Veterans residing in underserved rural areas face many barriers to accessing high-quality rehabilitation services. This article describes the benefits and challenges of using technology for delivery of rehabilitation services to rural Veterans using TeleHOME, an innovative tele-rehabilitation program. TeleHOME enables rehabilitation providers to remotely assess the Veteran's functional abilities and needs in his or her own home where these tasks must be performed. This technology increases the ability of all team members to contribute to interdisciplinary care, but also requires greater levels of team integration. One month after the completion of the TeleHOME project, we met with clinicians to discuss their perceptions of whether and how use of the technology affected interdisciplinary care processes, and what approaches were used to meet team-based goals. TeleHOME can improve access to rehabilitation services for rural Veterans, but will also bring about novel integrative care processes that may improve the effectiveness of such services. Recommendations to overcome challenges to optimize the implementation and delivery of TeleHOME services as well as to better inform clinicians working with rural Veterans are discussed. PMID:27580283

  15. Fuel Cells: Status and Challenges in Materials and Technologies

    SciTech Connect

    Yang, Z Gary

    2006-08-01

    Fuel cells are electrochemical devices that directly convert the chemical energy in incoming fuel (hydrogen or a hydrogen rich reformate) into electrical energy via ionic conducting electrolyte membranes. Depending on the electrolyte used, fuel cells can be classified into a number of types. Two major types of fuel cells, polymeric-electrolyte-membrane fuel cell (PEMFC) and solid-oxide fuel cell (SOFC), have attracted the most recent attention and are the subject of extensive R&D efforts worldwide. PEMFCs are typically based on a proton conductive sulphonated fluoropolymer membrane such as Nafion? and operate in the 60-80 C temperature range. On the other hand, SOFCs are constructed from an oxygen ion conductive membrane, such as YSZ (yttria stabilized zirconia), and operate in the range of 600-1,000 C. To build up a useful voltage, a series of cells, comprised of an anode and a cathode in addition to the electrolyte, are electrically connected and integrated into a stack via interconnects or bi-polar plates. For designs such as the planar one, seals are required in the stack to prevent leakage and to separate the fuel at the anode side from the oxygen or air at the cathode side.

  16. CONVERTING PYROLYSIS OILS TO RENEWABLE TRANSPORT FUELS: PROCESSING CHALLENGES & OPPORTUNITIES

    SciTech Connect

    Holmgren, Jennifer; Nair, Prabhakar N.; Elliott, Douglas C.; Bain, Richard; Marinangelli, Richard

    2008-03-11

    To enable a sustained supply of biomass-based transportation fuels, the capability to process feedstocks outside the food chain must be developed. Significant industry efforts are underway to develop these new technologies, such as converting cellulosic wastes to ethanol. UOP, in partnership with U.S. Government labs, NREL and PNNL, is developing an alternate route using cellulosic feedstocks. The waste biomass is first subjected to a fast pyrolysis operation to generate pyrolysis oil (pyoil for short). Current efforts are focused on developing a thermochemical platform to convert pyoils to renewable gasoline, diesel and jet fuel. The fuels produced will be indistinguishable from their fossil fuel counterparts and, therefore, will be compatible with existing transport and distribution infrastructure.

  17. Benefits and Challenges of Linking Green Infrastructure and Highway Planning in the United States

    NASA Astrophysics Data System (ADS)

    Marcucci, Daniel J.; Jordan, Lauren M.

    2013-01-01

    Landscape-level green infrastructure creates a network of natural and semi-natural areas that protects and enhances ecosystem services, regenerative capacities, and ecological dynamism over long timeframes. It can also enhance quality of life and certain economic activity. Highways create a network for moving goods and services efficiently, enabling commerce, and improving mobility. A fundamentally profound conflict exists between transportation planning and green infrastructure planning because they both seek to create connected, functioning networks across the same landscapes and regions, but transportation networks, especially in the form of highways, fragment and disconnect green infrastructure networks. A key opportunity has emerged in the United States during the last ten years with the promotion of measures to link transportation and environmental concerns. In this article we examined the potential benefits and challenges of linking landscape-level green infrastructure planning and implementation with integrated transportation planning and highway project development in the United States policy context. This was done by establishing a conceptual model that identified logical flow lines from planning to implementation as well as the potential interconnectors between green infrastructure and highway infrastructure. We analyzed the relationship of these activities through literature review, policy analysis, and a case study of a suburban Maryland, USA landscape. We found that regionally developed and adopted green infrastructure plans can be instrumental in creating more responsive regional transportation plans and streamlining the project environmental review process while enabling better outcomes by enabling more targeted mitigation. In order for benefits to occur, however, landscape-scale green infrastructure assessments and plans must be in place before integrated transportation planning and highway project development occurs. It is in the transportation

  18. Involving Community Health Workers in the Centers for Population Health and Health Disparities Research Projects: Benefits and Challenges.

    PubMed

    Krok-Schoen, Jessica L; Weier, Rory C; Hohl, Sarah D; Thompson, Beti; Paskett, Electra D

    2016-01-01

    Understanding the benefits and challenges of including community health workers (CHWs) in health disparities research can improve planning and delivery of culturally appropriate interventions. Representatives from 18 projects from the Centers for Population Health and Health Disparities (CPHHD) initiative completed an online questionnaire about the benefits and challenges of involving CHWs in their research. Eight emergent themes were classified into two categories: 1) Personal qualities and background CHWs bring to research including community knowledge and cultural sensitivity to improve recruitment and effectiveness of interventions; and 2) Workplace demands of CHWs including human resource policies and processes, research skills/background (training needs), and oversight despite distance. These findings demonstrate the benefits of involving CHWs in research and draw attention to the hiring, training, and oversight of CHWs and subsequent challenges. Additional research is needed to understand interactions between project staff and CHWs better and to identify best practices to involve CHWs in research. PMID:27524766

  19. Estimating the climate and air quality benefits of aviation fuel and emissions reductions

    NASA Astrophysics Data System (ADS)

    Dorbian, Christopher S.; Wolfe, Philip J.; Waitz, Ian A.

    2011-05-01

    In this study we consider the implications of our current understanding of aviation climate impacts as it relates to the ratio of non-CO 2 to CO 2 effects from aviation. We take as inputs recent estimates from the literature of the magnitude of the component aviation impacts and associated uncertainties. We then employ a simplified probabilistic impulse response function model for the climate and a range of damage functions to estimate the ratio of non-CO 2 to CO 2 impacts of aviation for a range of different metrics, scientific assumptions, future background emissions scenarios, economic growth scenarios, and discount rates. We take cost-benefit analysis as our primary context and thus focus on integral metrics that can be related to damages: the global warming potential, the time-integrated change in surface temperature, and the net present value of damages. We also present results based on an endpoint metric, the global temperature change potential. These latter results would be more appropriate for use in a cost-effectiveness framework (e.g., with a well-defined policy target for the anthropogenic change in surface temperature at a specified time in the future). We find that the parameter that most influences the ratio of non-CO 2 to CO 2 impacts of aviation is the discount rate, or analogously the time window used for physical metrics; both are expressions of the relative importance of long-lived versus short-lived impacts. Second to this is the influence of the radiative forcing values that are assumed for aviation-induced cloudiness effects. Given the large uncertainties in short-lived effects from aviation, and the dominating influence of discounting or time-windowing, we find that the choice of metric is relatively less influential. We express the ratios of non-CO 2 to CO 2 impacts on a per unit fuel burn basis so that they can be multiplied by a social cost of carbon to estimate the additional benefits of fuel burn reductions from aviation beyond those

  20. Fuel cells for transportation: Status, opportunities and challenges

    SciTech Connect

    Lloyd, A.C.; Leonard, J.H.

    1996-12-31

    Environmental issues will become important drivers influencing technology in the years ahead. For example, air quality legislation and regulation - locally, regionally, and globally - will continue to play an increasing role in influencing decisions made in choosing a particular energy source. Health concerns related to ambient fine particles and the ongoing debate on global climate change and the need to reduce CO{sub 2} emissions are two examples of the nexus between energy and the environment. Additionally, as conventional sources of energy and petroleum become depleted and as political issues remain, desires for energy diversity and energy security will require a menu of technologies and fuels. It is recognized that many of the renewable and environmentally benign fuels and energy sources are expensive and that economics will play a key role in dictating which of these is going to be most successful. For example, generating hydrogen from wind or solar is expensive compared to conventional technologies and price competition is likely to be more intense in the area of electricity de-regulation. However, the cost of conventional fuels are also increasing because of a desire to clean them up or a desire to change their chemical and physical properties through partial oxidation or steam reforming. These additional treatments lead to increased costs so that the gap between the {open_quotes}clean{close_quotes} fuels and cleaning up conventional fuels becomes much narrower.

  1. Changing the Way NASA Airborne Science Data Are Managed: Challenges and Benefits

    NASA Astrophysics Data System (ADS)

    Walter, J.; Ramapriyan, H. K.

    2011-12-01

    For many years NASA has supported the collection of in-situ and remotely sensed science data through the use of airborne platforms. The Airborne Science Program, as part of NASA's Earth Science Division (ESD), currently supports and manages these investigations. The data collected under this program have many uses including, but certainly not limited to, calibration and validation of satellite based measurements and retrieval algorithms, testing new sensor technologies, and measuring the vertical and horizontal distribution of atmospheric constituents. In the past, management of the data was typically the responsibility of the individual principal investigators. Along the way many highly customized strategies for dealing with data discovery, access, distribution, formatting, and preservation issues were developed. In an effort to assure that airborne science data are managed in a more coherent and uniform manner across the program, airborne missions are now being required to adhere to the NASA Earth science data policy and a specific set of Level 1 data management requirements derived from that policy. These requirements include use of NASA ESD-approved data formats and metadata specifications, elimination of periods of exclusive access, and the transfer of data products to a NASA ESD-assigned Data Center. In addition, the manner in which each mission plans to meet these requirements must be documented in a data management plan. The good news is that there is a significant Earth science data management infrastructure in place that can be leveraged to help meet these requirements. However, much of this infrastructure was developed to support satellite missions. Since airborne data are different than satellite data in many ways, this presents some challenges. This presentation will describe the challenges as well as the benefits of this new data management policy.

  2. Electrocatalyst approaches and challenges for automotive fuel cells.

    PubMed

    Debe, Mark K

    2012-06-01

    Fuel cells powered by hydrogen from secure and renewable sources are the ideal solution for non-polluting vehicles, and extensive research and development on all aspects of this technology over the past fifteen years has delivered prototype cars with impressive performances. But taking the step towards successful commercialization requires oxygen reduction electrocatalysts--crucial components at the heart of fuel cells--that meet exacting performance targets. In addition, these catalyst systems will need to be highly durable, fault-tolerant and amenable to high-volume production with high yields and exceptional quality. Not all the catalyst approaches currently being pursued will meet those demands. PMID:22678278

  3. Genomic analysis in the clinic: benefits and challenges for health care professionals and patients in Brazil.

    PubMed

    Ashton-Prolla, Patrícia; Goldim, José Roberto; Vairo, Filippo Pinto E; da Silveira Matte, Ursula; Sequeiros, Jorge

    2015-07-01

    Despite significant advances in the diagnosis and treatment of genetic diseases in the last two decades, there is still a significant proportion where a causative mutation cannot be identified and a definitive genetic diagnosis remains elusive. New genome-wide or high-throughput multiple gene tests have brought new hope to the field, since they can offer fast, cost-effective and comprehensive analysis of genetic variation. This is particularly interesting in disorders with high genetic heterogeneity. There are, however, limitations and concerns regarding the implementation of genomic analysis in everyday clinical practice, including some particular to emerging and developing economies, as Brazil. They include the limited number of actionable genetic variants known to date, difficulties in determining the clinical validity and utility of novel variants, growth of direct-to-consumer genetic testing using a genomic approach and lack of proper training of health care professionals to adequately request, interpret and use genetic information. Despite all these concerns and limitations, the availability of genomic tests has grown at an extremely rapid pace and commercially available services include initiatives in almost all areas of clinical genetics, including newborn and carrier screening. We discuss the benefits and limitations of genomic testing, as well as the ethical implications and the challenges for genetic education and enough available and qualified health care professionals, to ensure the adequate process of informed consent, meaningful interpretation and use of genomic data and definition of a clear regulatory framework in the particular context of Brazil. PMID:26040235

  4. Challenges and benefits of endogenous steroid analysis by LC-MS/MS.

    PubMed

    Couchman, Lewis; Vincent, Royce P; Ghataore, Lea; Moniz, Caje F; Taylor, Norman F

    2011-11-01

    Quantification of endogenous hormonal steroids and their precursors is essential for diagnosing a wide range of endocrine disorders. Historically, these analyses have been carried out using immunoassay, but such methods are problematic, especially for low-concentration analytes, due to assay interference by other endogenous steroids. MS offers improved specificity over immunoassay and can be highly sensitive. GC-MS, with use of stable isotopically labeled internal standards, is considered the 'gold standard' method for serum steroid analysis. GC-MS is the method of choice for profiling steroid metabolites in urine, but these techniques are not appropriate for routine use in clinical laboratories owing to a need for extensive sample preparation, as well as analytical expertise. LC-MS/MS compares well to GC-MS in terms of accuracy, precision and sensitivity, but allows simplified sample preparation. While most publications have featured only one or a limited number of steroids, we consider that steroid paneling (which we propose as the preferred term for multitargeted steroid analysis) has great potential to enable clinicians to make a definitive diagnosis. It is adaptable for use in a number of matrices, including serum, saliva and dried blood spots. However, LC-MS/MS-based steroid analysis is not straightforward, and understanding the chemical and analytical processes involved is essential for implementation of a robust clinical service. This article discusses specific challenges in the measurement of endogenous steroids using LC-MS/MS, and provides examples of the benefits it offers. PMID:22122603

  5. Investigating Epigenetic Effects of Prenatal Exposure to Toxic Metals in Newborns: Challenges and Benefits

    PubMed Central

    Nye, Monica D.; Fry, Rebecca C.; Hoyo, Cathrine; Murphy, Susan K.

    2014-01-01

    Increasing evidence suggest that epigenetic alterations can greatly impact human health, and that epigenetic mechanisms (DNA methylation, histone modifications, and microRNAs) may be particularly relevant in responding to environmental toxicant exposure early in life. The epigenome plays a vital role in embryonic development, tissue differentiation and disease development by controlling gene expression. In this review we discuss what is currently known about epigenetic alterations in response to prenatal exposure to inorganic arsenic (iAs) and lead (Pb), focusing specifically on their effects on DNA methylation. We then describe how epigenetic alterations are being studied in newborns as potential biomarkers of in utero environmental toxicant exposure, and the benefits and challenges of this approach. In summary, the studies highlighted herein indicate how epigenetic mechanisms are impacted by early life exposure to iAs and Pb, and the research that is being done to move towards understanding the relationships between toxicant-induced epigenetic alterations and disease development. Although much remains unknown, several groups are working to understand the correlative and causal effects of early life toxic metal exposure on epigenetic changes and how these changes may result in later development of disease. PMID:24955086

  6. BioGPS and GXD: mouse gene expression data - the benefits and challenges of data integration

    PubMed Central

    Wu, Chunlei

    2012-01-01

    Mouse gene expression data are complex and voluminous. To maximize the utility of these data, they must be made readily accessible through databases, and those resources need to place the expression data in the larger biological context. Here we describe two community resources that approach these problems in different but complementary ways: BioGPS and the Mouse Gene Expression Database (GXD). BioGPS connects its large and homogenous microarray gene expression reference data sets via plugins with a heterogeneous collection of external gene centric resources, thus casting a wide but loose net. GXD acquires different types of expression data from many sources and integrates these data tightly with other types of data in the Mouse Genome Informatics (MGI) resource, with a strong emphasis on consistency checks and manual curation. We describe and contrast the “loose” and “tight” data integration strategies employed by BioGPS and GXD, respectively, and discuss the challenges and benefits of data integration. BioGPS is freely available at http://biogps.org. GXD is freely available through the Mouse Genome Informatics (MGI) web site (www.informatics.jax.org), or directly at www.informatics.jax.org/expression.shtml. PMID:22847375

  7. IED Cleanup: A Cooperative Classroom Robotics Challenge--The Benefits and Execution of a Cooperative Classroom Robotics Challenge

    ERIC Educational Resources Information Center

    Piotrowski, Mark; Kressly, Rich

    2009-01-01

    This article describes a cooperative classroom robotics challenge named "IED Cleanup". This classroom challenge was created to incorporate a humanitarian project with the use of a robotics design system in order to remove simulated IEDs (Improvised Explosive Devices) to a detonation zone within a specified amount of time. Throughout the activity,…

  8. A COMPARISON OF CHALLENGES ASSOCIATED WITH SLUDGE REMOVAL & TREATMENT & DISPOSAL AT SEVERAL SPENT FUEL STORAGE LOCATIONS

    SciTech Connect

    PERES, M.W.

    2007-01-09

    Challenges associated with the materials that remain in spent fuel storage pools are emerging as countries deal with issues related to storing and cleaning up nuclear fuel left over from weapons production. The K Basins at the Department of Energy's site at Hanford in southeastern Washington State are an example. Years of corrosion products and piles of discarded debris are intermingled in the bottom of these two pools that stored more 2,100 metric tons (2,300 tons) of spent fuel. Difficult, costly projects are underway to remove radioactive material from the K Basins. Similar challenges exist at other locations around the globe. This paper compares the challenges of handling and treating radioactive sludge at several locations storing spent nuclear fuel.

  9. E-health: potential benefits and challenges in providing and accessing sexual health services

    PubMed Central

    2013-01-01

    Background E-health has become a burgeoning field in which health professionals and health consumers create and seek information. E-health refers to internet-based health care and information delivery and seeks to improve health service locally, regionally and worldwide. E-sexual health presents new opportunities to provide online sexual health services irrespective of gender, age, sexual orientation and location. Discussion The paper used the dimensions of the RE-AIM model (reach, efficacy, adoption, implementation and maintenance) as a guiding principle to discuss potentials of E-health in providing and accessing sexual health services. There are important issues in relation to utilising and providing online sexual health services. For healthcare providers, e-health can act as an opportunity to enhance their clients’ sexual health care by facilitating communication with full privacy and confidentiality, reducing administrative costs and improving efficiency and flexibility as well as market sexual health services and products. Sexual health is one of the common health topics which both younger and older people explore on the internet and they increasingly prefer sexual health education to be interactive, non-discriminate and anonymous. This commentary presents and discusses the benefits of e-sexual health and provides recommendations towards addressing some of the emerging challenges. Future directions The provision of sexual health services can be enhanced through E-health technology. Doing this can empower consumers to engage with information technology to enhance their sexual health knowledge and quality of life and address some of the stigma associated with diversity in sexualities and sexual health experiences. In addition, e-sexual health may better support and enhance the relationship between consumers and their health care providers across different locations. However, a systematic and focused approach to research and the application of findings in

  10. Potential benefits from the use of JP-8 fuel in military ground equipment. Interim report, October 1987-February 1989

    SciTech Connect

    Montemayor, A.F.; Stavinoha, L.L.; Lestz, S.J.; LePera, M.E.

    1989-02-01

    The U.S. DoD is moving toward the use of JP-8 as a single fuel for use in Europe. Many potential benefits are associated with exclusive use of JP-8 in U.S. DOD equipment. This study discusses these benefits and provides references for further study. Some of the benefits associated with use of JP-8 will be immediate, and some will require time to be appreciated. Some benefits will accrue during peacetime operations, and some will be most apparent during times of conflict. As JP-8 finds increasing use in field tests and conversions of military bases, there will no doubt be problems that arise alongside the benefits. Careful weighing of the benefits and problems will ultimately lead to optimal usage of fuel resources and hopefully, increased readiness. The main benefits associated with use of JP-8 in military ground equipment are simplified logistics, increased readiness, reduced exhaust emissions, and better lubricant life. The information contained in this report is intended to delineate those areas where the use of JP-8 will prove beneficial and alert those personnel that will be affected by the change. Introduction of JP-8 into the military system should proceed. The most useful demonstration programs will be operations that involve joint operations of forces to include Army ground and aviation activities. These operations should be monitored for benefits as well as possible problems and the lessons learned applied accordingly. Jet engine fuels; Kerosene; Fuel additives; Diesel fuels; Compression/ignition engines; Sulfur/exhaust emissions/particulates; Logistics; Military/ground/combat vehicles.

  11. Benefits and Challenges of Technology in High Schools: A Voice from Educational Leaders with a Freire Echo

    ERIC Educational Resources Information Center

    Preston, Jane P.; Wiebe, Sean; Gabriel, Martha; McAuley, Alexander; Campbell, Barbara; MacDonald, Ron

    2015-01-01

    The purpose of this study is to document the perceptions of school leaders pertaining to the benefits and challenges of technology in high schools located on Prince Edward Island (PEI) (Canada). For this qualitative study, we interviewed 11 educational leaders representing the PEI Department of Education, principals, vice-principals, and…

  12. Insights of Public High School Teachers and Administrators Regarding the Benefits and Challenges of Co-Teaching

    ERIC Educational Resources Information Center

    Dagna, Jeanne M.

    2012-01-01

    The purpose of this study was to identify the benefits and challenges of co-teaching, as self-reported by high school general education teachers, special education teachers, and administrators and determine if they shared common beliefs regarding supporting students with special needs within the general education curriculum. Participants included…

  13. Benefits and Challenges of Information and Communication Technologies (ICT) Integration in Québec English Schools

    ERIC Educational Resources Information Center

    Rabah, Jihan

    2015-01-01

    This paper investigated teachers' and educational consultants' perceptions of ICT integration in Québec English Schools, specifically with regards to the benefits and challenges of ICT integration therein. 23 teachers and educational consultants from seven different school boards participated in the focus group sessions. Results revealed higher…

  14. How Benefits and Challenges of Personal Response System Impact Students' Continuance Intention? A Taiwanese Context

    ERIC Educational Resources Information Center

    Yeh, C. Rosa; Tao, Yu-Hui

    2013-01-01

    To address four issues observed from the latest Personal Response System (PRS) review by Kay and LeSage (2009), this paper investigates, through a systematic research, how the derived benefits and challenges of PRS affect the satisfaction and continuance intention of college students in Taiwan. The empirical study samples representative college…

  15. Business Education Students' Evaluation of the Benefits and Challenges Confronting Student Industrial Works Experience Scheme in Edo and Delta States

    ERIC Educational Resources Information Center

    Olumese, H. A.; Ediagbonya, Kennedy

    2016-01-01

    This research paper specifically investigated Business Education students' evaluation of the benefits and challenges confronting Student Industrial Works Experience Scheme (SIWES) in Edo and Delta States. Two research questions were raised to guide the study and were answered descriptively. The descriptive survey research design was adopted for…

  16. PBL in the Era of Reform Standards: Challenges and Benefits Perceived by Teachers in One Elementary School

    ERIC Educational Resources Information Center

    Nariman, Nahid; Chrispeels, Janet

    2016-01-01

    We explore teachers' efforts to implement problem-based learning (PBL) in an elementary school serving predominantly English learners. Teachers had an opportunity to implement the Next Generation Science Standards (NGSS) using PBL in a summer school setting with no test-pressures. To understand the challenges and benefits of PBL implementation, a…

  17. Outlook for benefits of sediment microbial fuel cells with two bio‐electrodes

    PubMed Central

    De Schamphelaire, Liesje; Rabaey, Korneel; Boeckx, Pascal; Boon, Nico; Verstraete, Willy

    2008-01-01

    Summary The benefits of sediment microbial fuel cells (SMFCs) go beyond energy generation for low‐power applications. Aside from producing electrical energy, SMFCs can enhance the oxidation of reduced compounds at the anode, thus bringing about the removal of excessive or unwanted reducing equivalents from submerged soils. Moreover, an SMFC could be applied to control redox‐dependent processes in sediment layers. Several cathodic reactions that may drive these sediment oxidation reactions are examined. Special attention is given to two biologically mediated cathodic reactions, respectively employing an oxygen reduction and a manganese cycle. Both reactions imply a low cost and a high electrode potential and are of interest for reactor‐type MFCs as well as for SMFCs. PMID:21261866

  18. IEEE 802.16J-Relay Fortified Aeromacs Networks; Benefits and Challenges

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Apaza, Rafael D.

    2014-01-01

    Aeronautical Mobile Airport Communications System (AeroMACS) is an IEEE 802.16 standard-based (WiMAX) broadband aviation transmission technology, developed to provide safety critical communications coverage for airport surface in support of fixed and mobile ground to ground applications and services. We have previously demonstrated that IEEE 802.16j-amendment-based WiMAX is most feasible for AeroMACS applications. The principal argument in favor of application of IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified WiMAX networks, with virtually no increase in the power requirements. In this article, following introductory remarks on airport surface communications, WiMAX and AeroMACS; the IEEE 802.16j-based WiMAX technology and multihop relay systems are briefly described. The two modes of relay operation supported by IEEE 802.16j amendment; i.e., transparent (TRS) and non-transparent (NTRS) modes, are discussed in some detail. Advantages and disadvantages of using TRS and NTRS in AeroMACS networks are summarized in a table. Practical issues vis--vis the inclusion of relays in AeroMACS networks are addressed. It is argued that the selection of relay type may affect a number of network parameters. A discussion on specific benefits and challenges of inclusion of relays in AeroMACS networks is provided. The article concludes that in case it is desired or necessary to exclusively employ one type of relay mode for all applications throughout an AeroMACS network, the proper selection would be the non-transparent mode.

  19. Benefits of a Graduate Business Degree: Students' Perspectives and Universities' Challenges.

    ERIC Educational Resources Information Center

    Webb, Marion Stanton; Allen, Lida Cherie

    1995-01-01

    A survey of 1,499 graduate business students at 7 colleges and universities investigated perceptions of potential benefits of an advanced degree, and their relationships with degree type, school size/type, and student characteristics. Five perceived benefits included research and analytical skills, competitive advantage, monetary reward, career…

  20. Cost-Benefit Analysis of Flexibility Retrofits for Coal and Gas-Fueled Power Plants: August 2012 - December 2013

    SciTech Connect

    Venkataraman, S.; Jordan, G.; O'Connor, M.; Kumar, N.; Lefton, S.; Lew, D.; Brinkman, G.; Palchak, D.; Cochran, J.

    2013-12-01

    High penetrations of wind and solar power plants can induce on/off cycling and ramping of fossil-fueled generators. This can lead to wear-and-tear costs and changes in emissions for fossil-fueled generators. Phase 2 of the Western Wind and Solar Integration Study (WWSIS-2) determined these costs and emissions and simulated grid operations to investigate the full impact of wind and solar on the fossil-fueled fleet. This report studies the costs and benefits of retrofitting existing units for improved operational flexibility (i.e., capability to turndown lower, start and stop faster, and ramp faster between load set-points).

  1. Examination of the costs, benefits and enery conservation aspects of the NASA aircraft fuel conservation technology program

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The costs and benefits of the NASA Aircraft Fuel Conservation Technology Program are discussed. Consideration is given to a present worth analysis of the planned program expenditures, an examination of the fuel savings to be obtained by the year 2005 and the worth of this fuel savings relative to the investment required, a comparison of the program funding with that planned by other Federal agencies for energy conservation, an examination of the private industry aeronautical research and technology financial posture for the period FY 76 - FY 85, and an assessment of the potential impacts on air and noise pollution. To aid in this analysis, a computerized fleet mix forecasting model was developed. This model enables the estimation of fuel consumption and present worth of fuel expenditures for selected commerical aircraft fleet mix scenarios.

  2. Assessment of the benefits of distributed fuel cell generators in the service areas of Central and South West Services, Inc.. Final report

    SciTech Connect

    El-Gasseir, M.M.

    1993-10-01

    A framework and methodology for assessing the cost effectiveness of 2-MW molten-carbonate fuel cell (MCFC) generators have been developed and used for a number of specific applications and sites within the service territories of the four operating companies of Central and South West Corporation (CSW). The analyses indicate that the MCFC`s relatively small size and its other design and operating characteristics create an opportunity for securing a number of benefits in addition to its capacity and energy values. The combined levelized values of the identified non-traditional or distributed benefits range from 6 to 71 mills/kWh (in 1991 currency) for a 1997 market-entry unit, and from 16 to 67 mills/kWh for a commercial facility in the Year 2000. Because of such savings, the projected total levelized benefits of MCFC generation varied from approximately 63 to 125 and 72 to 127 mills/kWh for the 1997 and 2000 units, respectively. These values correspond to benefit-to-cost ratios of 0.69--1.3 for the market entry fuel cell and 1.1--1.9 for the commercial unit. These estimates are indicative of the competitiveness of MCFC generation in comparison with current technology, including combined cycle plants. Although the results are not accurate projections of future benefit values and are contingent upon satisfactory performance of the MCFC facility, they are indicative of the potential opportunities and challenges that distributed generation poses for CSW and its operating companies. The new technology could be used to lower the cost of service for all customers in the future. It might also provide an additional instrument for the competition to make in-roads into operating companies` markets. The development of MCFC generators along with current cost and performance projections could have far reaching impacts on the electric utility industry.

  3. Hybrid-Electric Passenger Car Carbon Dioxide and Fuel Consumption Benefits Based on Real-World Driving.

    PubMed

    Holmén, Britt A; Sentoff, Karen M

    2015-08-18

    Hybrid-electric vehicles (HEVs) have lower fuel consumption and carbon dioxide (CO2) emissions than conventional vehicles (CVs), on average, based on laboratory tests, but there is a paucity of real-world, on-road HEV emissions and performance data needed to assess energy use and emissions associated with real-world driving, including the effects of road grade. This need is especially great as the electrification of the passenger vehicle fleet (from HEVs to PHEVs to BEVs) increases in response to climate and energy concerns. We compared tailpipe CO2 emissions and fuel consumption of an HEV passenger car to a CV of the same make and model during real-world, on-the-road network driving to quantify the in-use benefit of one popular full HEV technology. Using vehicle specific power (VSP) assignments that account for measured road grade, the mean CV/HEV ratios of CO2 tailpipe emissions or fuel consumption defined the corresponding HEV "benefit" factor for each VSP class (1 kW/ton resolution). Averaging over all VSP classes for driving in all seasons, including temperatures from -13 to +35 °C in relatively steep (-13.2 to +11.5% grade), hilly terrain, mean (±SD) CO2 emission benefit factors were 4.5 ± 3.6, 2.5 ± 1.7, and 1.4 ± 0.5 for city, exurban/suburban arterial and highway driving, respectively. Benefit factor magnitude corresponded to the frequency of electric-drive-only (EDO) operation, which was modeled as a logarithmic function of VSP. A combined model explained 95% of the variance in HEV benefit for city, 75% for arterial and 57% for highway driving. Benefit factors consistently exceeded 2 for VSP classes with greater than 50% EDO (i.e., only city and arterial driving). The reported HEV benefits account for real-world road grade that is often neglected in regulatory emissions and fuel economy tests. Fuel use HEV benefit factors were 1.3 and 2 for the regulatory highway (HWFET) and city (FTP) cycles, respectively, 18% and 31% higher than the EPA adjusted

  4. The challenges of fuel options for the new generation of Indian thermal power plants

    SciTech Connect

    Roy, C.; Sanyal, A.

    1999-07-01

    The selection of fuel supply is probably the most important challenge a potential power project developer for a new Indian thermal power plant has to face when considering the overall project economics. The paper reviews the essential issues and the effect of fuel selection on project costs of the new generation of thermal power plants of India. Coal, lignite and natural gas are India's indigenous fossil fuel resources for power generation. The country has a modest reserve of petroleum crude. India is the world's third largest coal producer and has 205 billion metric tons of assessed and 73 billion tons of proven reserves. The indigenous supply of petroleum is unlikely to improve much in the near future. Liquid fuel based generation is therefore marginal in the country. Although coal will continue to be the mainstay fuel, there is a short term need to examine the possibility of using alternative fuels due to two basic reasons: (a) A 70 million tons of shortfall is forecast for the power sector during the 1997--2002 period. The deficit has to be met by either import of coal or other fuels. Development of new mines is a long gestation activity. (b) There is an uneven geographical location of Indian coal reserves. For the load centers, which are distant from the indigenous coal sources, use of alternative fuel could also prove to be economical in the long term. Moving coal will become harder in view of the high demands being placed on the railways by many other sectors.

  5. Nanomaterials for Polymer Electrolyte Membrane Fuel Cells; Materials Challenges Facing Electrical Energy Storate

    SciTech Connect

    Gopal Rao, MRS Web-Editor; Yury Gogotsi, Drexel University; Karen Swider-Lyons, Naval Research Laboratory

    2010-08-05

    Symposium T: Nanomaterials for Polymer Electrolyte Membrane Fuel Cells Polymer electrolyte membrane (PEM) fuel cells are under intense investigation worldwide for applications ranging from transportation to portable power. The purpose of this seminar is to focus on the nanomaterials and nanostructures inherent to polymer fuel cells. Symposium topics will range from high-activity cathode and anode catalysts, to theory and new analytical methods. Symposium U: Materials Challenges Facing Electrical Energy Storage Electricity, which can be generated in a variety of ways, offers a great potential for meeting future energy demands as a clean and efficient energy source. However, the use of electricity generated from renewable sources, such as wind or sunlight, requires efficient electrical energy storage. This symposium will cover the latest material developments for batteries, advanced capacitors, and related technologies, with a focus on new or emerging materials science challenges.

  6. The public health benefits of reducing fine particulate matter through conversion to cleaner heating fuels in New York City.

    PubMed

    Kheirbek, Iyad; Haney, Jay; Douglas, Sharon; Ito, Kazuhiko; Caputo, Steven; Matte, Thomas

    2014-12-01

    In recent years, both New York State and City issued regulations to reduce emissions from burning heating oil. To assess the benefits of these programs in New York City, where the density of emissions and vulnerable populations vary greatly, we simulated the air quality benefits of scenarios reflecting no action, partial, and complete phase-out of high-sulfur heating fuels using the Community MultiScale Air Quality (CMAQ) model conducted at a high spatial resolution (1 km). We evaluated the premature mortality and morbidity benefits of the scenarios within 42 city neighborhoods and computed benefits by neighborhood poverty status. The complete phase-out scenario reduces annual average fine particulate matter (PM2.5) by an estimated 0.71 μg/m(3) city-wide (average of 1 km estimates, 10-90th percentile: 0.1-1.6 μg/m(3)), avoiding an estimated 290 premature deaths, 180 hospital admissions for respiratory and cardiovascular disease, and 550 emergency department visits for asthma each year. The largest improvements were seen in areas of highest building and population density and the majority of benefits have occurred through the partial phase out of high-sulfur heating fuel already achieved. While emissions reductions were greatest in low-poverty neighborhoods, health benefits are estimated to be greatest in high-poverty neighborhoods due to higher baseline morbidity and mortality rates. PMID:25365783

  7. All Around the Block: The Benefits and Challenges of a Non-traditional School Schedule.

    ERIC Educational Resources Information Center

    Rettig, Michael D.; Canady, Robert Lynn

    1996-01-01

    Block schedules offer many advantages, including increased usable instructional time, increased opportunities to use alternative instructional strategies, and fewer homework assignments and class changes for students. Challenges include maintaining student attention, providing balanced schedules, retaining major concepts, and accommodating…

  8. Medical education in the electronic medical record (EMR) era: benefits, challenges, and future directions.

    PubMed

    Tierney, Michael J; Pageler, Natalie M; Kahana, Madelyn; Pantaleoni, Julie L; Longhurst, Christopher A

    2013-06-01

    In the last decade, electronic medical record (EMR) use in academic medical centers has increased. Although many have lauded the clinical and operational benefits of EMRs, few have considered the effect these systems have on medical education. The authors review what has been documented about the effect of EMR use on medical learners through the lens of the Accreditation Council for Graduate Medical Education's six core competencies for medical education. They examine acknowledged benefits and educational risks to use of EMRs, consider factors that promote their successful use when implemented in academic environments, and identify areas of future research and optimization of EMRs' role in medical education. PMID:23619078

  9. An assessment of the benefits of the use of NASA developed fuel conservative technology in the US commercial aircraft fleet

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Cost and benefits of a fuel conservative aircraft technology program proposed by NASA are estimated. NASA defined six separate technology elements for the proposed program: (a) engine component improvement (b) composite structures (c) turboprops (d) laminar flow control (e) fuel conservative engine and (f) fuel conservative transport. There were two levels postulated: The baseline program was estimated to cost $490 million over 10 years with peak funding in 1980. The level two program was estimated to cost an additional $180 million also over 10 years. Discussions with NASA and with representatives of the major commercial airframe manufacturers were held to estimate the combinations of the technology elements most likely to be implemented, the potential fuel savings from each combination, and reasonable dates for incorporation of these new aircraft into the fleet.

  10. Implementing Structured English Immersion in Arizona: Benefits, Costs, Challenges, and Opportunities

    ERIC Educational Resources Information Center

    Rios-Aguilar, Cecilia; Gonzalez-Canche, Manuel; Moll, Luis C.

    2010-01-01

    This study conducted telephone interviews with 26 randomly selected English Language Coordinators from 26 Arizona school districts with enrollment patterns that were representative of the state as whole. Three primary questions were posed to the respondents: (a) How is the 4-hour ELD block being implemented?; (b) What are the benefits of the…

  11. Service-Learning in Supply Chain Management: Benefits, Challenges and Best Practices

    ERIC Educational Resources Information Center

    Schoenherr, Tobias

    2015-01-01

    Service-learning (SL) is a pedagogical approach in which students are assigned a course-related project in a not-for-profit organization, and are tasked to apply course content to execute the project. While the benefits are multifarious, only recently have supply chain management (SCM) courses adapted this innovative teaching methodology. The…

  12. Higher Education Experiences of Students with Autism Spectrum Disorder: Challenges, Benefits and Support Needs

    ERIC Educational Resources Information Center

    Van Hees, Valérie; Moyson, Tinneke; Roeyers, Herbert

    2015-01-01

    The transition into higher education constitutes a precarious life stage for students with autism spectrum disorder (ASD). Research on how students with ASD navigate college life is needed for the development of adequate support. This study investigated the challenges and support needs of 23 students with ASD in higher education through…

  13. The Use of Portfolios in Coordinated School Health Programs: Benefits and Challenges to Implementation

    ERIC Educational Resources Information Center

    Barnes, Seraphine Pitt; Torrens, Anna; George, Valerie; Brown, Kelli McCormack

    2007-01-01

    Background: Coordinated school health programs (CSHP) frequently struggle with how to adequately evaluate implementation. The CSHP framework provides flexibility in how it is implemented; however, this flexibility makes it a challenge to effectively evaluate. Portfolios have been used as a technique for evaluating progress and achievement. This…

  14. The Benefits and Challenges of Special Education Positions in Rural Settings: Listening to the Teachers

    ERIC Educational Resources Information Center

    Berry, Ann B.; Gravelle, Maggie

    2013-01-01

    Special education teachers, through a national survey conducted in 55 rural districts, provided information on the positive and negative aspects of teaching in rural schools. The 203 special educators were asked what they liked best about their position and what they found challenging. Some of the themes identified in the analysis centered on…

  15. A Cost-Benefit Analysis of the National Guard Youth ChalleNGe Program. Technical Report

    ERIC Educational Resources Information Center

    Perez-Arce, Francisco; Constant, Louay; Loughran, David S.; Karoly, Lynn A.

    2012-01-01

    Decades of research show that high school dropouts are more likely than graduates to commit crimes, abuse drugs and alcohol, have children out of wedlock, earn low wages, be unemployed, and suffer from poor health. The ChalleNGe program, currently operating in 27 states, is a residential program coupled with post-residential mentoring that seeks…

  16. Developing and using expert systems and neural networks in medicine: a review on benefits and challenges.

    PubMed

    Sheikhtaheri, Abbas; Sadoughi, Farahnaz; Hashemi Dehaghi, Zahra

    2014-09-01

    Complicacy of clinical decisions justifies utilization of information systems such as artificial intelligence (e.g. expert systems and neural networks) to achieve better decisions, however, application of these systems in the medical domain faces some challenges. We aimed at to review the applications of these systems in the medical domain and discuss about such challenges. Following a brief introduction of expert systems and neural networks by representing few examples, the challenges of these systems in the medical domain are discussed. We found that the applications of expert systems and artificial neural networks have been increased in the medical domain. These systems have shown many advantages such as utilization of experts' knowledge, gaining rare knowledge, more time for assessment of the decision, more consistent decisions, and shorter decision-making process. In spite of all these advantages, there are challenges ahead of developing and using such systems including maintenance, required experts, inputting patients' data into the system, problems for knowledge acquisition, problems in modeling medical knowledge, evaluation and validation of system performance, wrong recommendations and responsibility, limited domains of such systems and necessity of integrating such systems into the routine work flows. We concluded that expert systems and neural networks can be successfully used in medicine; however, there are many concerns and questions to be answered through future studies and discussions. PMID:25027017

  17. Benefits and Challenges of the Passport Broadcast Intervention in Long-Term Care

    ERIC Educational Resources Information Center

    Wittenberg-Lyles, Elaine; Oliver, Debra Parker; Demiris, George; Shaunfield, Sara

    2012-01-01

    Creative activities are a challenge for long-term care facilities. The Passport intervention uses web-based video technology to provide long-term care residents with a virtual travel experience. Passport broadcasts were conducted and staff and residents were interviewed about the experience. A thematic analysis of interviews was used to discern…

  18. The Benefits and Challenges of Becoming Cross-Culturally Competent Counseling Psychologists. Presidential Address

    ERIC Educational Resources Information Center

    Heppner, P. Paul

    2006-01-01

    The central thesis of this article is that focusing on cross-cultural competence will enhance both the science and the practice of counseling psychology. Developing cross-cultural competence is a lifelong journey, replete with many joys and challenges, that will (a) increase the sophistication of our research, (b) expand the utility and…

  19. Activity-Based Management System Implementation in Higher Education Institution: Benefits and Challenges

    ERIC Educational Resources Information Center

    Ismail, Noor Azizi

    2010-01-01

    Purpose: The purpose of this paper is to discuss how activity-based costing (ABC) technique can be applied in the context of higher education institutions. It also discusses the obstacles and challenges to the successful implementation of activity-based management (ABM) in the higher education environment. Design/methodology/approach: This paper…

  20. Appendix B: Hydrogen, Fuel Cells, and Infrastructure Technologies Program inputs for FY 2008 benefits estimates

    SciTech Connect

    None, None

    2009-01-18

    Document summarizes the results of the benefits analysis of EERE’s programs, as described in the FY 2008 Budget Request. EERE estimates benefits for its overall portfolio and nine Research, Development, Demonstration, and Deployment (RD3) programs.

  1. Culinary Herbs and Spices: Their Bioactive Properties, the Contribution of Polyphenols and the Challenges in Deducing Their True Health Benefits

    PubMed Central

    Opara, Elizabeth I.; Chohan, Magali

    2014-01-01

    Herbs and spices have been used for both culinary and medicinal purposes for centuries. Over the last decade, research into their role as contributors of dietary polyphenols, known to possess a number of properties associated with reducing the risk of developing chronic non-communicable diseases, has increased. However, bearing in mind how these foods are consumed, normally in small quantities and in combination with other foods, it is unclear what their true benefit is from a health perspective. The aim of this review is to use the literature to discuss how preparative and digestive processes, bioavailability and interactions between foods may influence the bioactive properties of these foods, and whether or not polyphenols are responsible for these properties. Furthermore, this review aims to highlight the challenges that need to be addressed so as to determine the true benefits of these foods and the mechanisms of action that underpin their purported efficacy. PMID:25340982

  2. Culinary herbs and spices: their bioactive properties, the contribution of polyphenols and the challenges in deducing their true health benefits.

    PubMed

    Opara, Elizabeth I; Chohan, Magali

    2014-01-01

    Herbs and spices have been used for both culinary and medicinal purposes for centuries. Over the last decade, research into their role as contributors of dietary polyphenols, known to possess a number of properties associated with reducing the risk of developing chronic non-communicable diseases, has increased. However, bearing in mind how these foods are consumed, normally in small quantities and in combination with other foods, it is unclear what their true benefit is from a health perspective. The aim of this review is to use the literature to discuss how preparative and digestive processes, bioavailability and interactions between foods may influence the bioactive properties of these foods, and whether or not polyphenols are responsible for these properties. Furthermore, this review aims to highlight the challenges that need to be addressed so as to determine the true benefits of these foods and the mechanisms of action that underpin their purported efficacy. PMID:25340982

  3. The challenges and opportunities for integration of solar syngas production with liquid fuel synthesis

    NASA Astrophysics Data System (ADS)

    Hinkley, James T.; McNaughton, Robbie K.; Pye, John; Saw, Woei; Stechel, Ellen B.

    2016-05-01

    Reforming of methane is practiced on a vast scale globally for the production of syngas as a precursor for the production of many commodities, including hydrogen, ammonia and synthetic liquid fuels. Solar reforming can reduce the greenhouse gas intensity of syngas production by up to about 40% by using solar thermal energy to provide the endothermic heat of reaction, traditionally supplied by combustion of some of the feed. This has the potential to enable the production of solar derived synthetic fuels as drop in replacements for conventional fuels with significantly lower CO2 intensity than conventional gas to liquids (GTL) processes. However, the intermittent nature of the solar resource - both diurnal and seasonal - poses significant challenges for such a concept, which relies on synthesis processes that typically run continuously on very stable feed compositions. We find that the integration of solar syngas production to a GTL process is a non-trivial exercise, with the ability to turn down the capacity of the GTL synthesis section, and indeed to suspend operations for short periods without significant detriment to product quality or process operability, likely to be a key driver for the commercial implementation of solar liquid fuels. Projected costs for liquid fuel synthesis suggest that solar reforming and small scale gas to liquid synthesis can potentially compete with conventional oil derived transport fuels in the short to medium term.

  4. Operation of molten carbonate fuel cells with different biogas sources: A challenging approach for field trials

    NASA Astrophysics Data System (ADS)

    Trogisch, S.; Hoffmann, J.; Daza Bertrand, L.

    In the past years research in the molten carbonate fuel cells (MCFC) area has been focusing its efforts on the utilisation of natural gas as fuel (S. Geitmann, Wasserstoff- & Brennstoffzellen-Projekte, 2002, ISBN 3-8311-3280-1). In order to increase the advantages of this technology, an international consortium has worked on the utilisation of biogas as fuel in MCFC. During the 4 years lasting RTD project EFFECTIVE two different gas upgrading systems have been developed and constructed together with two mobile MCFC test beds which were operated at different locations for approximately 2.000-5.000 h in each run with biogas from different origins and quality. The large variety of test locations has enabled to gather a large database for assessing the effect of the different biogas qualities on the complete system consisting of the upgrading and the fuel cell systems. The findings are challenging. This article also aims at giving an overview of the advantages of using biogas as fuel for fuel cells.

  5. Assessment of costs and benefits of flexible and alternative fuel use in the US transportation sector

    SciTech Connect

    Not Available

    1991-10-01

    The DOE is conducting a comprehensive technical analysis of a flexible-fuel transportation system in the United States -- that is, a system that could easily switch between petroleum and another fuel, depending on price and availability. The DOE Alternative Fuels Assessment is aimed directly at questions of energy security and fuel availability, but covers a wide range of issues. This report examines environmental, health, and safety concerns associated with a switch to alternative- and flexible-fuel vehicles. Three potential alternatives to oil-based fuels in the transportation sector are considered: methanol, compressed natural gas (CNG), and electricity. The objective is to describe and discuss qualitatively potential environmental, health, and safety issues that would accompany widespread use of these three fuels. This report presents the results of exhaustive literature reviews; discussions with specialists in the vehicular and fuel-production industries and with Federal, State, and local officials; and recent information from in-use fleet tests. Each chapter deals with the end-use and process emissions of air pollutants, presenting an overview of the potential air pollution contribution of the fuel --relative to that of gasoline and diesel fuel -- in various applications. Carbon monoxide, particulate matter, ozone precursors, and carbon dioxide are emphasized. 67 refs., 6 figs. , 8 tabs.

  6. Multitarget strategies in Alzheimer's disease: benefits and challenges on the road to therapeutics.

    PubMed

    Rosini, Michela; Simoni, Elena; Caporaso, Roberta; Minarini, Anna

    2016-04-01

    Alzheimer's disease is a multifactorial syndrome, for which effective cures are urgently needed. Seeking for enhanced therapeutic efficacy, multitarget drugs have been increasingly sought after over the last decades. They offer the attractive prospect of tackling intricate network effects, but with the benefits of a single-molecule therapy. Herein, we highlight relevant progress in the field, focusing on acetylcholinesterase inhibition and amyloid pathways as two pivotal features in multitarget design strategies. We also discuss the intertwined relationship between selected molecular targets and give a brief glimpse into the power of multitarget agents as pharmacological probes of Alzheimer's disease molecular mechanisms. PMID:27079260

  7. Assessment of costs and benefits of flexible and alternative fuel use in the US transportation sector

    SciTech Connect

    Not Available

    1990-12-01

    In 1988 the Department of Energy (DOE) undertook a comprehensive technical analysis of a flexible-fuel transportation system in the United States. During the next two decades, alternative fuels such as alcohol (methanol or ethanol), compressed natural gas (CNG), and electricity could become practical alternatives to oil-based fuels in the US transportation sector. The DOE Alternative Fuels Assessment is aimed directly at questions of energy security and fuel availability. To keep interested parties informed about the progress of the DOE Alternative Fuels Assessment, the Department periodically publishes reports dealing with particular aspects of this complex study. This report provides an analysis of the expected costs to produce methanol from biomass feedstock.

  8. Emerging Fuel Cell Technology Being Developed: Offers Many Benefits to Air Vehicles

    NASA Technical Reports Server (NTRS)

    Walker, James F.; Civinskas, Kestutis C.

    2004-01-01

    Fuel cells, which have recently received considerable attention for terrestrial applications ranging from automobiles to stationary power generation, may enable new aerospace missions as well as offer fuel savings, quiet operations, and reduced emissions for current and future aircraft. NASA has extensive experience with fuel cells, having used them on manned space flight systems over four decades. Consequently, the NASA Glenn Research Center has initiated an effort to investigate and develop fuel cell technologies for multiple aerospace applications. Two promising fuel cell types are the proton exchange membrane (PEM) and solid oxide fuel cell (SOFC). PEM technology, first used on the Gemini spacecraft in the sixties, remained unutilized thereafter until the automotive industry recently recognized the potential. PEM fuel cells are low-temperature devices offering quick startup time but requiring relatively pure hydrogen fuel. In contrast, SOFCs operate at high temperatures and tolerate higher levels of impurities. This flexibility allows SOFCs to use hydrocarbon fuels, which is an important factor considering our current liquid petroleum infrastructure. However, depending on the specific application, either PEM or SOFC can be attractive. As only NASA can, the Agency is pursuing fuel cell technology for civil uninhabited aerial vehicles (UAVs) because it offers enhanced scientific capabilities, including enabling highaltitude, long-endurance missions. The NASA Helios aircraft demonstrated altitudes approaching 100,000 ft using solar power in 2001, and future plans include the development of a regenerative PEM fuel cell to provide nighttime power. Unique to NASA's mission, the high-altitude aircraft application requires the PEM fuel cell to operate on pure oxygen, instead of the air typical of terrestrial applications.

  9. The 1992 natural gas vehicle challenge: EPA emissions and fuel economy testing

    NASA Astrophysics Data System (ADS)

    Bruetsch, Robert I.; Reineman, Martin E.

    1992-06-01

    The report describes the results of a student alternative fuels engineering design competition called the 1992 Natural Gas Vehicle Challenge which was held April 22 through June 1, 1992. Students from eighteen universities in the United States and four universities in Canada competed. the objective of this competition for each participating team was to convert a gaseoline-fueled General Motors (GM) Sierra pickup truck to natural gas operation and complete with students from other universities in the areas of exhaust emissions, fuel economy, performance, and design. This report also includes the comparisons between the results of the student compressed natural gas pickup truck conversions and the test results of similar gasoline-powered trucks and a dedicated compressed natural gas truck provided by General Motors.

  10. The Controversy, Challenges, and Potential Benefits of Putative Female Germline Stem Cells Research in Mammals

    PubMed Central

    Pan, Zezheng; Sun, Mengli; Liang, Xia; Li, Jia; Zhou, Fangyue; Zhong, Zhisheng; Zheng, Yuehui

    2016-01-01

    The conventional view is that female mammals lose their ability to generate new germ cells after birth. However, in recent years, researchers have successfully isolated and cultured a type of germ cell from postnatal ovaries in a variety of mammalian species that have the abilities of self-proliferation and differentiation into oocytes, and this finding indicates that putative germline stem cells maybe exist in the postnatal mammalian ovaries. Herein, we review the research history and discovery of putative female germline stem cells, the concept that putative germline stem cells exist in the postnatal mammalian ovary, and the research progress, challenge, and application of putative germline stem cells in recent years. PMID:26788065

  11. The Controversy, Challenges, and Potential Benefits of Putative Female Germline Stem Cells Research in Mammals.

    PubMed

    Pan, Zezheng; Sun, Mengli; Liang, Xia; Li, Jia; Zhou, Fangyue; Zhong, Zhisheng; Zheng, Yuehui

    2016-01-01

    The conventional view is that female mammals lose their ability to generate new germ cells after birth. However, in recent years, researchers have successfully isolated and cultured a type of germ cell from postnatal ovaries in a variety of mammalian species that have the abilities of self-proliferation and differentiation into oocytes, and this finding indicates that putative germline stem cells maybe exist in the postnatal mammalian ovaries. Herein, we review the research history and discovery of putative female germline stem cells, the concept that putative germline stem cells exist in the postnatal mammalian ovary, and the research progress, challenge, and application of putative germline stem cells in recent years. PMID:26788065

  12. The benefits and costs of new fuels and engines for light-duty vehicles in the United States.

    PubMed

    Keefe, Ryan; Griffin, James P; Graham, John D

    2008-10-01

    Rising oil prices and concerns about energy security and climate change are spurring reconsideration of both automobile propulsion systems and the fuels that supply energy to them. In addition to the gasoline internal combustion engine, recent years have seen alternatives develop in the automotive marketplace. Currently, hybrid-electric vehicles, advanced diesels, and flex-fuel vehicles running on a high percentage mixture of ethanol and gasoline (E85) are appearing at auto shows and in driveways. We conduct a rigorous benefit-cost analysis from both the private and societal perspective of the marginal benefits and costs of each technology--using the conventional gasoline engine as a baseline. The private perspective considers only those factors that influence the decisions of individual consumers, while the societal perspective accounts for environmental, energy, and congestion externalities as well. Our analysis illustrates that both hybrids and diesels show promise for particular light-duty applications (sport utility vehicles and pickup trucks), but that vehicles running continuously on E85 consistently have greater costs than benefits. The results for diesels were particularly robust over a wide range of sensitivity analyses. The results from the societal analysis are qualitatively similar to the private analysis, demonstrating that the most relevant factors to the benefit-cost calculations are the factors that drive the individual consumer's decision. We conclude with a brief discussion of marketplace and public policy trends that will both illustrate and influence the relative adoption of these alternative technologies in the United States in the coming decade. PMID:18684162

  13. Moving Toward Space Internetworking via DTN: Its Operational Challenges, Benefits, and Management

    NASA Technical Reports Server (NTRS)

    Barkley, Erik; Burleigh, Scott; Gladden, Roy; Malhotra, Shan; Shames, Peter

    2010-01-01

    The international space community has begun to recognize that the established model for management of communications with spacecraft - commanded data transmission over individual pair-wise contacts - is operationally unwieldy and will not scale in support of increasingly complex and sophisticated missions such as NASA's Constellation project. Accordingly, the international Inter-Agency Operations Advisory Group (IOAG) ichartered a Space Internetworking Strategy Group (SISG), which released its initial recommendations in a November 2008 report. The report includes a recommendation that the space flight community adopt Delay-Tolerant Networking (DTN) to address the problem of interoperability and communication scaling, especially in mission environments where there are multiple spacecraft operating in concert. This paper explores some of the issues that must be addressed in implementing, deploying, and operating DTN as part of a multi-mission, multi-agency space internetwork as well as benefits and future operational scenarios afforded by DTN-based space internetworking.

  14. Challenging children in kin versus nonkin foster care: perceived costs and benefits to caregivers.

    PubMed

    Timmer, Susan G; Sedlar, Georganna; Urquiza, Anthony J

    2004-08-01

    This study uses social exchange theory as a framework for examining 102 kin and 157 nonkin foster parents' perceptions of their foster children, their relationships with them, and their own functioning. The authors argue that these perceptions reflect perceived costs and benefits of parenting these children, which may influence their investment in them. All children in the study were referred to Parent-Child Interaction Therapy (PCIT) for treatment of the children's behavior problems, participating with their foster parents. Analyses showed that nonkin caregivers rated their foster children's behavior problems as significantly more severe than kin caregivers but rated themselves as significantly less stressed. Analyses predicting early treatment termination showed that kin caregivers were more likely than nonkin caregivers to complete the course of treatment in PCIT, particularly if they reported elevated levels of parental distress. The authors discuss the implications of these findings for foster children's placement stability and long-term success. PMID:15245678

  15. Minimally Invasive Surgery in Gastrointestinal Cancer: Benefits, Challenges, and Solutions for Underutilization

    PubMed Central

    Gusani, Niraj J.; Kimchi, Eric T.; Kavic, Stephen M.

    2014-01-01

    Background and Objectives: After the widespread application of minimally invasive surgery for benign diseases and given its proven safety and efficacy, minimally invasive surgery for gastrointestinal cancer has gained substantial attention in the past several years. Despite the large number of publications on the topic and level I evidence to support its use in colon cancer, minimally invasive surgery for most gastrointestinal malignancies is still underused. Methods: We explore some of the challenges that face the fusion of minimally invasive surgery technology in the management of gastrointestinal malignancies and propose solutions that may help increase the utilization in the future. These solutions are based on extensive literature review, observation of current trends and practices in this field, and discussion made with experts in the field. Results: We propose 4 different solutions to increase the use of minimally invasive surgery in the treatment of gastrointestinal malignancies: collaboration between surgical oncologists/hepatopancreatobiliary surgeons and minimally invasive surgeons at the same institution; a single surgeon performing 2 fellowships in surgical oncology/hepatopancreatobiliary surgery and minimally invasive surgery; establishing centers of excellence in minimally invasive gastrointestinal cancer management; and finally, using robotic technology to help with complex laparoscopic skills. Conclusions: Multiple studies have confirmed the utility of minimally invasive surgery techniques in dealing with patients with gastrointestinal malignancies. However, training continues to be the most important challenge that faces the use of minimally invasive surgery in the management of gastrointestinal malignancy; implementation of our proposed solutions may help increase the rate of adoption in the future. PMID:25489209

  16. Evaluating potential benefits of burning lower quality fuel oils using the oil burn optimization model

    SciTech Connect

    Babilonia, P.

    1995-09-01

    As a result of a 1987 New York State Public Service Commission Audit of Niagara Mohawk`s Fuel Supply operations, Niagara Mohawk (NMPC) became interested in analyzing the plant performance impacts of burning fuels of differing qualities at its various generating stations. Black & Veatch (B&V) had previously developed a computer model for EPRI that analyzed coal quality impacts (i.e., Coal Quality Impact Model). As a result of B&V`s work, NMPC contracted with B&V to first develop custom-designed software for its coal stations (Coal Burn Optimization Model (CBOM)). Subsequently, B&V was retained to develop a similar designed software for its oil stations, Oswego and Albany Steam Stations. The Oil Burn Optimization Model (OBOM) was, therefore, developed. OBOM was designed to be used to evaluate residual fuel oil supply options by predicting their fuel-related plant operating and maintenance costs. Fuel oil-related costs can also be compared to natural gas-related costs. Costs are estimated by predicting performance of various plant equipment. Predictions focus on combustion calculations, material flows, auxiliary power, boiler efficiency, precipitator and fan performance, fuel pumping and preheating requirements, and corrosion considerations. Total costs at the busbar attributed to fuel are calculated from these predictions. OBOM is a PC-based system operating under MS-DOS. The model produces hard copy results for quick comparison of fuels and their potential effects on plant operating and maintenance costs.

  17. Feasibility, benefits and challenges of using telemonitoring for the aging with Developmental Disabilities (DD): An exploratory study

    PubMed Central

    Nambisan, Priya; Lamkin, Donna; DeLong, Carrie

    2014-01-01

    Telemonitoring is being increasingly used to provide services to patients with developmental disabilities in residential community settings. The objective of this study is to assess the feasibility, benefits and challenges of using telemonitoring for aging patients with developmental disabilities. We also assess the benefits and challenges of telemonitoring for the caregivers of these patients. Focus groups and questionnaire-based surveys were used to collect data from patients and caregivers. The study found that telemonitoring was feasible and beneficial for the aging with developmental disabilities, albeit for those who are moderate to high functioning. It was not beneficial or feasible for those with very low functional capabilities. The study found that telemonitoring was beneficial towards providing more independence, more self-confidence in carrying out daily activities, and more knowledge regarding their disease. The study also found that telemonitoring was useful for caregivers to better understand their patients and their needs, better coordinate the services delivered, and to enhance the satisfaction of caregiving. The discussions include limitations of using quantitative methods in this type of setting. PMID:25422722

  18. Feasibility, benefits and challenges of using telemonitoring for the aging with Developmental Disabilities (DD): An exploratory study.

    PubMed

    Nambisan, Priya; Lamkin, Donna; DeLong, Carrie

    2014-01-01

    Telemonitoring is being increasingly used to provide services to patients with developmental disabilities in residential community settings. The objective of this study is to assess the feasibility, benefits and challenges of using telemonitoring for aging patients with developmental disabilities. We also assess the benefits and challenges of telemonitoring for the caregivers of these patients. Focus groups and questionnaire-based surveys were used to collect data from patients and caregivers. The study found that telemonitoring was feasible and beneficial for the aging with developmental disabilities, albeit for those who are moderate to high functioning. It was not beneficial or feasible for those with very low functional capabilities. The study found that telemonitoring was beneficial towards providing more independence, more self-confidence in carrying out daily activities, and more knowledge regarding their disease. The study also found that telemonitoring was useful for caregivers to better understand their patients and their needs, better coordinate the services delivered, and to enhance the satisfaction of caregiving. The discussions include limitations of using quantitative methods in this type of setting. PMID:25422722

  19. Meaningful use of health information technology: evidence suggests benefits and challenges lie ahead.

    PubMed

    Furukawa, Michael F; Poon, Eric

    2011-12-01

    Less than 3 years into the passage of the Health Information Technology for Economic and Clinical Health (HITECH) provisions of the American Recovery and Reinvestment Act of 2009, measurable results are emerging. For example, in the first 11 months during which healthcare providers ("eligible professionals") and acute care hospitals ("eligible hospitals") had the opportunity to demonstrate stage 1 "Meaningful Use" of Healthcare Information Technology (HIT), more than 20,000 "eligible professionals" and 750 "eligible hospitals" have done so. In the current issue of The American Journal of Managed Care, we showcase examples of HITECH's potential impact, as well as illustrate the opportunities and challenges ahead. Two studies in this issue illustrate how HIT can improve the capacity of our healthcare system to manage chronic illnesses. The study by Vollmer et al describes how an interactive voice recognition system can improve adherence to inhaled corticosteroids among individuals with asthma in a large health maintenance organization. Shelley's study shows that the combination of electronic medical records, clinical decision support, and performance feedback can improve the rate of blood pressure control in patients with hypertension who receive care in community health centers. Together, these studies provide hope that the nation's investment in HIT could one day yield clinical dividends. Three other studies in this issue suggest that success for HIT will require attention to both technological and sociological factors. The study by Millery et al attributes the success of an HIT-based intervention to a multi-faceted approach that involves a combination of decision support tools, systematic provider feedback, implementation support, and leadership. Results from Abramson's study suggest that the full error-reduction potential of e-prescribing may only be reached with the combination of on-line clinical decision support and support for clinicians. The study by

  20. Viewing Health Care Delivery as Science: Challenges, Benefits, and Policy Implications

    PubMed Central

    Pronovost, Peter J; Goeschel, Christine A

    2010-01-01

    The need for health services research is likely to rise rapidly as the population ages, health care costs soar, and therapeutic and diagnostic choices proliferate. Building an effective and efficient health care delivery system is a national priority. Yet the national health care quality report concludes that we lack the ability to monitor progress toward even basic quality and patient safety goals effectively. The gap between the need to improve and our ability to do so exists in part because we fail to view the delivery of health care as science, we lack national improvement priorities, and we lack a national infrastructure to achieve our stated goals. We discuss key challenges implicit in correcting these failures and recommend actions to expedite progress. PMID:21054369

  1. The complexity, challenges and benefits of comparing two transporter classification systems in TCDB and Pfam

    PubMed Central

    Chiang, Zachary; Vastermark, Ake; Punta, Marco; Coggill, Penelope C.; Mistry, Jaina; Finn, Robert D.

    2015-01-01

    Transport systems comprise roughly 10% of all proteins in a cell, playing critical roles in many processes. Improving and expanding their classification is an important goal that can affect studies ranging from comparative genomics to potential drug target searches. It is not surprising that different classification systems for transport proteins have arisen, be it within a specialized database, focused on this functional class of proteins, or as part of a broader classification system for all proteins. Two such databases are the Transporter Classification Database (TCDB) and the Protein family (Pfam) database. As part of a long-term endeavor to improve consistency between the two classification systems, we have compared transporter annotations in the two databases to understand the rationale for differences and to improve both systems. Differences sometimes reflect the fact that one database has a particular transporter family while the other does not. Differing family definitions and hierarchical organizations were reconciled, resulting in recognition of 69 Pfam ‘Domains of Unknown Function’, which proved to be transport protein families to be renamed using TCDB annotations. Of over 400 potential new Pfam families identified from TCDB, 10% have already been added to Pfam, and TCDB has created 60 new entries based on Pfam data. This work, for the first time, reveals the benefits of comprehensive database comparisons and explains the differences between Pfam and TCDB. PMID:25614388

  2. Information technology in pharmacovigilance: Benefits, challenges, and future directions from industry perspectives

    PubMed Central

    Lu, Zhengwu

    2009-01-01

    Risk assessment during clinical product development needs to be conducted in a thorough and rigorous manner. However, it is impossible to identify all safety concerns during controlled clinical trials. Once a product is marketed, there is generally a large increase in the number of patients exposed, including those with comorbid conditions and those being treated with concomitant medications. Therefore, postmarketing safety data collection and clinical risk assessment based on observational data are critical for evaluating and characterizing a product’s risk profile and for making informed decisions on risk minimization. Information science promises to deliver effective e-clinical or e-health solutions to realize several core benefits: time savings, high quality, cost reductions, and increased efficiencies with safer and more efficacious medicines. The development and use of standard-based pharmacovigilance system with integration connection to electronic medical records, electronic health records, and clinical data management system holds promise as a tool for enabling early drug safety detections, data mining, results interpretation, assisting in safety decision making, and clinical collaborations among clinical partners or different functional groups. The availability of a publicly accessible global safety database updated on a frequent basis would further enhance detection and communication about safety issues. Due to recent high-profile drug safety problems, the pharmaceutical industry is faced with greater regulatory enforcement and increased accountability demands for the protection and welfare of patients. This changing climate requires biopharmaceutical companies to take a more proactive approach in dealing with drug safety and pharmacovigilance. PMID:21701609

  3. Teaching Outside the Box: Challenging Gifted Students with Polar Sciences Without Benefit of a Science Classroom

    NASA Astrophysics Data System (ADS)

    Dooley, J.

    2013-12-01

    In the high-stakes-testing world of one-size-fits-most educational practices, it is often the needs of the most able students that are unmet, yet these high ability learners can benefit greatly from exploration in the area of polar science. With school schedules and budgets already stretched to the breaking point and Common Core (CCSS) subjects are the focus, very few resources remain for topics considered by some as unimportant. Polar and climate science are prime examples. Here, a council member of Polar Educators International and Gifted Education Teacher, shares resources and ideas to engage this unique group of students and others. She draws from experiences and knowledge gained through ANDRILL's Arise Educator program, IPY Oslo and Montreal PolarEDUCATOR workshops, and Consortium for Ocean Leadership's Deep Earth Academy. Topics include School-wide Enrichment through use of ANDRILL's Flexhibit material and participation in Antarctica Day, afterschool Deep Freeze clubs that presented in public outreach venues for polar science events at the Maryland Science Center in Baltimore and NYC's Museum of Natural History, group project work using IODP core data from Antarctica, interaction with polar scientists via Skype, and other projects.

  4. Pathway databases and tools for their exploitation: benefits, current limitations and challenges

    PubMed Central

    Bauer-Mehren, Anna; Furlong, Laura I; Sanz, Ferran

    2009-01-01

    In past years, comprehensive representations of cell signalling pathways have been developed by manual curation from literature, which requires huge effort and would benefit from information stored in databases and from automatic retrieval and integration methods. Once a reconstruction of the network of interactions is achieved, analysis of its structural features and its dynamic behaviour can take place. Mathematical modelling techniques are used to simulate the complex behaviour of cell signalling networks, which ultimately sheds light on the mechanisms leading to complex diseases or helps in the identification of drug targets. A variety of databases containing information on cell signalling pathways have been developed in conjunction with methodologies to access and analyse the data. In principle, the scenario is prepared to make the most of this information for the analysis of the dynamics of signalling pathways. However, are the knowledge repositories of signalling pathways ready to realize the systems biology promise? In this article we aim to initiate this discussion and to provide some insights on this issue. PMID:19638971

  5. The benefits and challenges of a fitness and lifestyle enhancement program for correctional officers.

    PubMed

    Jetté, M; Sidney, K

    1991-01-01

    This paper documents the benefits and difficulties encountered in the development of an on-site exercise and lifestyle enhancement program for correctional officers. 25 male correctional officers participated in a 6.5-week strength and aerobic training program integrated with penitentiary duties. 21 officers were available for retesting. The program was associated with decreases in body weight, skinfold thickness, cholesterol levels and increases in HDL-cholesterol, chest girth, strength scores and muscular endurance. Resting heart rates and systolic blood pressures were reduced but there was no significant change in maximal oxygen consumption. Furthermore, there were favourable changes in smoking and alcohol consumption, sleeping patterns, nutritional habits and tolerance of stress. These results are probably typical of what can be expected from a program of this type. We conclude that a brief at-work exercise and health enhancement program can exert positive but modest influences on the fitness, health and lifestyle of correctional officers, without undermining security of the institution. However, if this type of program is to achieve beneficial effects on health and fitness, a number of difficulties must be addressed. PMID:2009486

  6. Air Quality Benefits of Ship Fuel Regulations in the San Francisco Bay Area

    NASA Astrophysics Data System (ADS)

    Tao, L.; Harley, R. A.; Fairley, D.; Martien, P. T.

    2012-12-01

    Ocean-going vessels burning high-sulfur heavy fuel oil are an important emission source of air pollutants such as sulfur dioxide and particulate matter. Beginning July 1, 2009, an emission control area was put into effect at ports and along the California coastline, requiring use of low-sulfur marine fuels in place of heavy fuel oil in main engines of ships. To assess impacts of the fuel changes on air quality at the Port of Oakland and in the surrounding San Francisco Bay area, we analyzed speciated fine particle composition data from 4 urban sites and 2 more remote sites (Point Reyes and Pinnacles) from the IMPROVE network. Measured changes in concentrations of vanadium, a useful and specific tracer for heavy fuel oil combustion, are related to overall changes in primary aerosol emissions from ships. The results indicate a substantial reduction in vanadium concentrations after the fuel change, and a 13 to 38% decrease in SO2 concentration, with the SO2 decrease varying depending on proximity to shipping lanes. We inferred from emission factors documented in the literature that marine vessel contributions to primary fine particulate matter mass in the Bay Area, prior to the fuel change, were on the order of 1 to 5%.

  7. Certification challenges in the development of an innovative high payload capacity spent fuel transportation cask

    SciTech Connect

    Mair, B.R.; Severson, M.J.; Ciez, A.P. )

    1990-01-01

    The design approach and certification strategy used in the development of an innovative transportation cask for legal weight truck shipments of spent nuclear fuel is presented. The proposed approach represents a significant departure from conventional cask designs in that it uses titanium alloy, a material with a high strength-to-weight ratio which has no precedent in transportation cask certification. The significant increase in payload obtainable with the proposed approach, and the associated benefits such as reduced life cycle costs, lower personnel exposure, and lower transportation accident risks are discussed. 8 refs., 3 figs., 1 tab.

  8. Use of online clinical videos for clinical skills training for medical students: benefits and challenges

    PubMed Central

    2014-01-01

    Background Multimedia learning has been shown effective in clinical skills training. Yet, use of technology presents both opportunities and challenges to learners. The present study investigated student use and perceptions of online clinical videos for learning clinical skills and in preparing for OSCE (Objective Structured Clinical Examination). This study aims to inform us how to make more effective us of these resources. Methods A mixed-methods study was conducted for this study. A 30-items questionnaire was administered to investigate student use and perceptions of OSCE videos. Year 3 and 4 students from 34 Korean medical schools who had access to OSCE videos participated in the online survey. Additionally, a semi-structured interview of a group of Year 3 medical students was conducted for an in-depth understanding of student experience with OSCE videos. Results 411 students from 31 medical schools returned the questionnaires; a majority of them found OSCE videos effective for their learning of clinical skills and in preparing for OSCE. The number of OSCE videos that the students viewed was moderately associated with their self-efficacy and preparedness for OSCE (p < 0.05). One-thirds of those surveyed accessed the video clips using mobile devices; they agreed more with the statement that it was convenient to access the video clips than their peers who accessed the videos using computers (p < 0.05). Still, students reported lack of integration into the curriculum and lack of interaction as barriers to more effective use of OSCE videos. Conclusions The present study confirms the overall positive impact of OSCE videos on student learning of clinical skills. Having faculty integrate these learning resources into their teaching, integrating interactive tools into this e-learning environment to foster interactions, and using mobile devices for convenient access are recommended to help students make more effective use of these resources. PMID:24650290

  9. The challenges of fuel options for the new generation of Indian thermal power plants

    SciTech Connect

    Roy, C.; Pande, S.; Sanyal, A.

    1999-11-01

    The selection of fuel supply is probably the most important challenge a potential power project developer for a new Indian thermal power plant has to face when considering the overall project economics. The paper reviews the essential issues and the effect of fuel selection on project costs of the new generation of thermal power plants of India. The electric power sector has taken great strides since the beginning of the planning process, over 45 years ago. It has been unable to keep pace with the rapid growth of demand, primarily due to resource constraints. Changes in the Government policy in 1991 brought fundamental changes to the power sector. The opening up of the sector and the consequent changes in the power policy, evoked great interest from private local and foreign-investors. However, mainly dud to the poor financial position of the State Electricity Boards (SEBs), few proposals settled. Uncertainty relating to fuel, multiple negotiating agencies and financing posed great challenges for developers. As of March 1997, the installed capacity of Indian utilities was 85,266 MW. Power generation in 1996--97 was 394 billion units with a plant load factor of a more 64.5%.

  10. Xylose fermentation as a challenge for commercialization of lignocellulosic fuels and chemicals.

    PubMed

    Sànchez Nogué, Violeta; Karhumaa, Kaisa

    2015-04-01

    Fuel ethanol production from lignocellulosic materials is at a level where commercial biofuel production is becoming a reality. The solubilization of the hemicellulose fraction in lignocellulosic-based feedstocks results in a large variety of sugar mixtures including xylose. However, allowing xylose fermentation in yeast that normally is used for fuel ethanol production requires genetic engineering. Moreover, the efficiency of lignocellulosic pretreatment, together with the release and generation of inhibitory compounds in this step, are some of the new challenges faced during second generation ethanol production. Successful advances in all these aspects will improve ethanol yield, productivity and titer, which will reduce the impact on capital and operating costs, leading to the consolidation of the fermentation of lignocellulosic biomass as an economically feasible option for the production of renewable fuels. Therefore the development of yeast strains capable of fermenting a wide variety of sugars in a highly inhibitory environment, while maintaining a high ethanol yield and production rate, is required. This review provides an overview of the current status in the use of xylose-engineered yeast strains and describes the remaining challenges to achieve an efficient deployment of lignocellulosic-based ethanol production. PMID:25522734

  11. The Challenges Associated with High Burnup and High Temperature for UO2 TRISO-Coated Particle Fuel

    SciTech Connect

    David Petti; John Maki

    2005-02-01

    The fuel service conditions for the DOE Next Generation Nuclear Plant (NGNP) will be challenging. All major fuel related design parameters (burnup, temperature, fast neutron fluence, power density, particle packing fraction) exceed the values that were qualified in the successful German UO2 TRISO-coated particle fuel development program in the 1980s. While TRISO-coated particle fuel has been irradiated at NGNP relevant levels for two or three of the design parameters, no data exist for TRISO-coated particle fuel for all five parameters simultaneously. Of particular concern are the high burnup and high temperatures expected in the NGNP. In this paper, where possible, we evaluate the challenges associated with high burnup and high temperature quantitatively by examining the performance of the fuel in terms of different known failure mechanisms. Potential design solutions to ameliorate the negative effects of high burnup and high temperature are also discussed.

  12. NIOZ high-resolution moored temperature observations: benefits and new challenges.

    NASA Astrophysics Data System (ADS)

    Cimatoribus, Andrea; Gostiaux, Louis; Cyr, Frederic; van Haren, Hans

    2016-04-01

    internal wave spectrum, modulation by submesoscale and mesoscale activity and seasonal variations. These features have been exploited for characterising the internal wave spectrum in the open ocean, for evaluating turbulence parameters above seamounts, and to characterise the statistics of temperature fluctuations. Main results include the observational demonstration of extreme inhomogeneity in space and intermittency in time of turbulence, and evidence of the importance of convective activity within strong geophysical turbulence. The data collected challenges the classical methods of turbulence parameters estimation in the ocean. Classical "Thorpe scale" methods have been adapted to the particular characteristics of the data, and efforts have been made to adapt other methods, providing higher detail on the vertical and temporal modulation of turbulence. The large datasets have also enabled the application on observational data of analysis methods previously used on laboratory data alone.

  13. Perceived benefits and challenges of repeated exposure to high fidelity simulation experiences of first degree accelerated bachelor nursing students.

    PubMed

    Kaddoura, Mahmoud; Vandyke, Olga; Smallwood, Christopher; Gonzalez, Kristen Mathieu

    2016-01-01

    This study explored perceptions of first-degree entry-level accelerated bachelor nursing students regarding benefits and challenges of exposure to multiple high fidelity simulation (HFS) scenarios, which has not been studied to date. These perceptions conformed to some research findings among Associate Degree, traditional non-accelerated, and second-degree accelerated Bachelor of Science in Nursing (BSN) students faced with one to two simulations. However, first-degree accelerated BSN students faced with multiple complex simulations perceived improvements on all outcomes, including critical thinking, confidence, competence, and theory-practice integration. On the negative side, some reported feeling overwhelmed by the multiple HFS scenarios. Evidence from this study supports HFS as an effective teaching and learning method for nursing students, along with valuable implications for many other fields. PMID:26260522

  14. Key challenges and recent progress in batteries, fuel cells, and hydrogen storage for clean energy systems

    NASA Astrophysics Data System (ADS)

    Chalk, Steven G.; Miller, James F.

    Reducing or eliminating the dependency on petroleum of transportation systems is a major element of US energy research activities. Batteries are a key enabling technology for the development of clean, fuel-efficient vehicles and are key to making today's hybrid electric vehicles a success. Fuel cells are the key enabling technology for a future hydrogen economy and have the potential to revolutionize the way we power our nations, offering cleaner, more efficient alternatives to today's technology. Additionally fuel cells are significantly more energy efficient than combustion-based power generation technologies. Fuel cells are projected to have energy efficiency twice that of internal combustion engines. However before fuel cells can realize their potential, significant challenges remain. The two most important are cost and durability for both automotive and stationary applications. Recent electrocatalyst developments have shown that Pt alloy catalysts have increased activity and greater durability than Pt catalysts. The durability of conventional fluorocarbon membranes is improving, and hydrocarbon-based membranes have also shown promise of equaling the performance of fluorocarbon membranes at lower cost. Recent announcements have also provided indications that fuel cells can start from freezing conditions without significant deterioration. Hydrogen storage systems for vehicles are inadequate to meet customer driving range expectations (>300 miles or 500 km) without intrusion into vehicle cargo or passenger space. The United States Department of Energy has established three centers of Excellence for hydrogen storage materials development. The centers are focused on complex metal hydrides that can be regenerated onboard a vehicle, chemical hydrides that require off-board reprocessing, and carbon-based storage materials. Recent developments have shown progress toward the 2010 DOE targets. In addition DOE has established an independent storage material testing center

  15. The benefits of a fast reactor closed fuel cycle in the UK

    SciTech Connect

    Gregg, R.; Hesketh, K.

    2013-07-01

    The work has shown that starting a fast reactor closed fuel cycle in the UK, requires virtually all of Britain's existing and future PWR spent fuel to be reprocessed, in order to obtain the plutonium needed. The existing UK Pu stockpile is sufficient to initially support only a modest SFR 'closed' fleet assuming spent fuel can be reprocessed shortly after discharge (i.e. after two years cooling). For a substantial fast reactor fleet, most Pu will have to originate from reprocessing future spent PWR fuel. Therefore, the maximum fast reactor fleet size will be limited by the preceding PWR fleet size, so scenarios involving fast reactors still require significant quantities of uranium ore indirectly. However, once a fast reactor fuel cycle has been established, the very substantial quantities of uranium tails in the UK would ensure there is sufficient material for several centuries. Both the short and long term impacts on a repository have been considered in this work. Over the short term, the decay heat emanating from the HLW and spent fuel will limit the density of waste within a repository. For scenarios involving fast reactors, the only significant heat bearing actinide content will be present in the final cores, resulting in a 50% overall reduction in decay energy deposited within the repository when compared with an equivalent open fuel cycle. Over the longer term, radiological dose becomes more important. Total radiotoxicity (normalised by electricity generated) is lower for scenarios with Pu recycle after 2000 years. Scenarios involving fast reactors have the lowest radiotoxicity since the quantities of certain actinides (Np, Pu and Am) eventually stabilise. However, total radiotoxicity as a measure of radiological risk does not account for differences in radionuclide mobility once in repository. Radiological dose is dominated by a small number of fission products so is therefore not affected significantly by reactor type or recycling strategy (since the

  16. Modelling the long-term impacts on affected children of adult HIV: benefits, challenges and a possible approach.

    PubMed

    Desmond, Christopher; Bruce, Faikah; Tomlinson, M; Marlow, Marguerite B; Aber, J Lawrence; Ouifki, Rachid; Welte, Alex

    2014-07-01

    We outline the benefits, challenges and possible approaches to developing mathematical models that could be used to estimate the magnitude of negative consequences of adult HIV infection for children. Adult HIV infection can lead to numerous negative consequences for dependent children, including depression, anxiety, withdrawal from school and early sexual debut, among others. For advocacy and planning purposes, it is important to highlight and consider as many of these as possible. A focus solely on orphan numbers, which is the typical summary measure for children affected by HIV and AIDS, can be misleading. The complexity of child development that is characterized by the interaction of a multitude of proximal and distal factors, coupled with a significant lack of data on child development in the context of adult HIV infection make the development of models a challenging task. Although it may not be possible in the first attempt to develop a population-based model capable of examining family dynamics, the negative consequences together with the impact of interventions, steps in that direction can be taken. We propose approaches and assumptions that we believe will allow the development of a useful first set of models. We conclude with a brief discussion of the type of data that, if collected, would facilitate refinement and development of these models. PMID:24991900

  17. Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel

    SciTech Connect

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-05-01

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellular measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.

  18. Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel

    DOE PAGESBeta

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-05-01

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellularmore » measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.« less

  19. Benefits of utilizing CellProfiler as a characterization tool for U–10Mo nuclear fuel

    SciTech Connect

    Collette, R.; Douglas, J.; Patterson, L.; Bahun, G.; King, J.; Keiser, D.; Schulthess, J.

    2015-07-15

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium–molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellular measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries. - Graphical abstract: Display Omitted - Highlights: • A technique is developed to score U–10Mo FIB-SEM image quality using CellProfiler. • The pass/fail metric is based on image illumination, focus, and area scratched. • Automated image analysis is performed in pipeline fashion to characterize images. • Fission gas void, interaction layer, and grain boundary coverage data is extracted. • Preliminary characterization results demonstrate consistency of the algorithm.

  20. Potential benefits of solar reflective car shells: cooler cabins, fuel savings and emission reductions

    SciTech Connect

    Levinson, Ronnen; Pan, Heng; Ban-Weiss, George; Rosado, Pablo; Paolini, Riccardo; Akbari, Hashem

    2011-05-11

    Abstract: Vehicle thermal loads and air conditioning ancillary loads are strongly influenced by the absorption of solar energy. The adoption of solar reflective coatings for opaque surfaces of the vehicle shell can decrease the ?soak? temperature of the air in the cabin of a vehicle parked in the sun, potentially reducing the vehicle?s ancillary load and improving its fuel economy by permitting the use of a smaller air conditioner. An experimental comparison of otherwise identical black and silver compact sedans indicated that increasing the solar reflectance (?) of the car?s shell by about 0.5 lowered the soak temperature of breath-level air by about 5?6?C. Thermal analysis predicts that the air conditioning capacity required to cool the cabin air in the silver car to 25?C within 30min is 13percent less than that required in the black car. Assuming that potential reductions in AC capacity and engine ancillary load scale linearly with increase in shell solar reflectance, ADVISOR simulations of the SC03 driving cycle indicate that substituting a typical cool-colored shell (?=0.35) for a black shell (?=0.05) would reduce fuel consumption by 0.12L per 100km (1.1percent), increasing fuel economy by 0.10kmL?1 [0.24mpg] (1.1percent). It would also decrease carbon dioxide (CO2) emissions by 2.7gkm?1 (1.1percent), nitrogen oxide (NOx) emissions by 5.4mgkm?1 (0.44percent), carbon monoxide (CO) emissions by 17mgkm?1 (0.43percent), and hydrocarbon (HC) emissions by 4.1mgkm?1 (0.37percent). Selecting a typical white or silver shell (?=0.60) instead of a black shell would lower fuel consumption by 0.21L per 100km (1.9percent), raising fuel economy by 0.19kmL?1 [0.44mpg] (2.0percent). It would also decrease CO2 emissions by 4.9gkm?1 (1.9percent), NOx emissions by 9.9mgkm?1 (0.80percent), CO emissions by 31mgkm?1 (0.79percent), and HC emissions by 7.4mgkm?1 (0.67percent). Our simulations may underestimate emission reductions because emissions in standardized driving cycles are

  1. On the benefits and challenges of a coordinated Validation and Quality Assessment of the GMES Service Element for Atmosphere (PROMOTE)

    NASA Astrophysics Data System (ADS)

    Rosalia Delgado Blanco, Maria; Lambert, Jean-Christopher; Skarlas, Pauline

    PROtocol MOniToring for the GMES Service Element for Atmosphere (PROMOTE) is an ESA- funded project delivering sustainable geo-spatial information services related to atmospheric ozone, surface UV exposure, air quality, climate change, and volcanic hazards to aviation. Services are based on ground-, airand satellite-based Earth observation data and on numerical models and assimilation systems. As a major step in the building of Global Monitoring of Environment and Security (GMES), a European contribution to the Global Earth Observation System of Systems (GEOSS), PROMOTE Services are to support informed decisions relevant to the nine Societal Benefit Areas addressed by GEOSS. GEOSS objectives of interoperability, sustainability, traceability and dedication to users are particular challenges that are addressed, among others, by the PROMOTE Validation Office. The first goal of this cross-cutting body is to ensure appropriate, user-driven quality assessment and validation of all PROMOTE services. Going beyond the classical validation of individual data products from a satellite or a model, the Validation Office verifies not only the "fitness for purpose" of all PROMOTE Products and Services against service specifications and user requirements, but also the "fitness for purpose" of the validation itself against user requirements, and generally coordinates validation activities at project level. A driving task under the responsibility of the Validation Office is to establish the PROMOTE Service Validation Protocol which sets the top-level definition of applicable standards and validation approaches for all constituents of the PROMOTE Service Portfolio. It is through the development and implementation of such a Validation Protocol, that the fitness for purpose of every product and service and of their validation can be assessed and sustained. At the same time, their compliance with high-level recommendations (e.g. GEO-CEOS Best Practices for Cal/Val) and regulations

  2. Microbial fuel cells and osmotic membrane bioreactors have mutual benefits for wastewater treatment and energy production.

    PubMed

    Hou, Dianxun; Lu, Lu; Ren, Zhiyong Jason

    2016-07-01

    This study demonstrates that microbial fuel cells (MFCs) and osmotic membrane bioreactors (OMBRs) can be mutually beneficial when integrated together for wastewater treatment. When connecting MFCs with OMBRs, the solute buildup increased conductivity and buffer capacity, which greatly increased MFC power density from 3 W/m(3) up to 11.5 W/m(3). In turn, the MFCs conditioned and reduced sludge production and therefore reduced forward osmosis (FO) membrane fouling. The MFC-OMBR equipped with new thin-film composite (TFC) membrane showed excellent organic (>95%) and phosphorus removal (>99%) and therefore maintained effluent sCOD below 20 mg/L. However, the nitrogen removal was limited due to the negative surface charge of the thin-film composite membrane and solution chemistry, which led to higher flux of ammonium toward the OMBR draw solution. Further studies are needed to improve nitrogen removal, reduce fouling, and optimize system integration. PMID:27105032

  3. Challenges faced when using radiocarbon measurements to estimate fossil fuel emissions in the UK.

    NASA Astrophysics Data System (ADS)

    Wenger, A.; O'Doherty, S.; Rigby, M. L.; Ganesan, A.; Manning, A.; Allen, G.

    2015-12-01

    Estimating the anthropogenic component of carbon dioxide emissions from direct atmospheric measurements is difficult, due to the large natural carbon dioxide fluxes. One way of determining the fossil fuel component of atmospheric carbon dioxide is the use of radiocarbon measurements. Whilst carbon reservoirs with a reasonably fast carbon exchange rate all have a similar radiocarbon content, fossil fuels are completely devoid of radiocarbon due to their age. Previous studies have 14CO2 (UK) this approach is compromised by the high density of 14CO2 emitting nuclear power plants. Of the 16 nuclear reactors in the UK, 14 are advanced gas cooled reactors, which have one of the highest 14CO2 emission rates of all reactor types. These radiocarbon emissions not only lead to a serious underestimation of the recently added fossil fuel CO2, by masking the depletion of 14C in CO2, but can in fact overshadow the depletion by a factor of 2 or more. While a correction for this enhancement can be applied, the emissions from the nuclear power plants are highly variable, and an accurate correction is therefore not straightforward. We present the first attempt to quantify UK fossil fuel CO2 emissions through the use of 14CO2. We employ a sampling strategy that makes use of a Lagrangian particle dispersion model, in combination with nuclear industry emission estimates, to forecast "good" sampling times, in an attempt to minimize the correction due to emissions from the nuclear industry. As part of the Greenhouse gAs Uk and Global Emissions (GAUGE) project, 14CO2measurements are performed at two measurement sites in the UK and Ireland, as well as during science flights around the UK. The measurement locations have been chosen with a focus on high emitting regions such as London and the Midlands. We discuss the unique challenges that face the determination of fossil fuel emissions through radiocarbon measurements in the UK and our sampling strategy to deal with them. In addition we

  4. Manufacturing Challenges and Benefits when Scaling the HIAD Stacked-Torus Aeroshell to a 15m-Class System

    NASA Technical Reports Server (NTRS)

    Swanson, Gregory; Cheatwood, Neil; Johnson, Keith; Calomino, Anthony; Gilles, Brian; Anderson, Paul; Bond, Bruce

    2016-01-01

    , and stitching of F-TPS gores. Additionally, new approaches and hardware will be required for handling and ground testing of both individual tori and the fully assembled HIADs.There are also noteworthy benefits of scaling up the HIAD aeroshell to a 15m-class system. Two complications in working with handmade textile structures are the non-linearity of the material components and the role of human accuracy during fabrication. Larger, more capable, HIAD structures should see much larger operational loads, potentially bringing the structural response of the material components out of the non-linear regime and into the preferred linear response range. Also, making the reasonable assumption that the magnitude of fabrication accuracy remains constant as the structures grow, the relative effect of fabrication errors should decrease as a percentage of the textile component size. Combined, these two effects improve the predictive capability and the uniformity of the structural response for a 12-15m HIAD.In this presentation, a handful of the challenges and associated mitigation plans will be discussed, as well as an update on current 12m aeroshell manufacturing and testing that is addressing these challenges

  5. Manufacturing Challenges and Benefits When Scaling the HIAD Stacked-Torus Aeroshell to a 15 Meter Class System

    NASA Technical Reports Server (NTRS)

    Swanson, G. T.; Cheatwood, F. M.; Johnson, R. K.; Hughes, S. J.; Calomino, A. M.

    2016-01-01

    structural webbing, initial inflation of tori, and stitching of F-TPS gores. Additionally, new approaches and hardware will be required for handling and ground testing of both individual tori and the fully assembled HIADs. There are also noteworthy benefits of scaling up the HIAD aeroshell to a 15m-class system. Two complications in working with handmade textile structures are the non-linearity of the material components and the role of human accuracy during fabrication. Larger, more capable, HIAD structures should see much larger operational loads, potentially bringing the structural response of the material components out of the non-linear regime and into the preferred linear response range. Also, making the reasonable assumption that the magnitude of fabrication accuracy remains constant as the structures grow, the relative effect of fabrication errors should decrease as a percentage of the textile component size. Combined, these two effects improve the predictive capability and the uniformity of the structural response for a 12-15-meter HIAD. In this presentation, a handful of the challenges and associated mitigation plans will be discussed, as well as an update on current manufacturing and testing that addressing these challenges.

  6. The Challenges and Benefits of Employing a Mobile Research Fellow to Facilitate Team Work on a Large, Interdisciplinary, Multi-Sited Project

    ERIC Educational Resources Information Center

    Sugden, Fraser; Punch, Samantha

    2014-01-01

    Over the last few years research funding has increasingly moved in favour of large, multi-partner, interdisciplinary and multi-site research projects. This article explores the benefits and challenges of employing a full-time research fellow to work across multiple field sites, with all the local research teams, on an international,…

  7. Preparing undergraduates for the future of scientific collaboration: Benefits, challenges and technological solutions in Distributed REU Sites

    NASA Astrophysics Data System (ADS)

    Hubenthal, M.; Anagnos, T.

    2012-12-01

    As research problems increasingly require multi-disciplinary approaches they naturally foster scientific collaborations between geographically distributed colleagues. This increasing trend in scientific research, the rapid evolution of communication technology, cognitive research into distance education, and the current generation of undergraduate students' eagerness to embrace and use technology, increases the relevance of distributed REU sites. Like traditional REU sites that host a cohort of students in one geographic location, distributed REU sites also seek to attract, nurture, and retain students in a STEM career pipeline. Distributed REU sites are unique in that some or all of the interns are geographically distributed during the research period. This arrangement allows the REU site to capitalize on distributed scientific resources such as field sites, research facilities, or human capital. At their core, distributed REU sites are fundamentally constructed of elements that have proven to be effective components of any undergraduate research experience. They also strive to develop and employ specialized programming that leverages collaboration tools through a cyberinfrastructure to enable interns to develop meaningful social and academic relationships with one another. Since 2006 the IRIS Consortium and NEES have facilitated separate, NSF funded, distributed REU Sites. Implementation and evaluations of these programs have revealed a number of successes and benefits. Longitudinal tracking indicates that distributed REU Sites are at least as successful as traditional sites in attracting, nurturing, and retaining students in a STEM career pipeline. A distributed arrangement also offers benefits over a traditional REU site, such as the flexibility to place interns at a variety of institutions with mentors making only an annual commitment to participate. This ensures that all mentors are eager to participate and are concerned with their intern's growth. It also

  8. Biodiesel biorefinery: opportunities and challenges for microbial production of fuels and chemicals from glycerol waste.

    PubMed

    Almeida, João R M; Fávaro, Léia C L; Quirino, Betania F

    2012-01-01

    The considerable increase in biodiesel production worldwide in the last 5 years resulted in a stoichiometric increased coproduction of crude glycerol. As an excess of crude glycerol has been produced, its value on market was reduced and it is becoming a "waste-stream" instead of a valuable "coproduct". The development of biorefineries, i.e. production of chemicals and power integrated with conversion processes of biomass into biofuels, has been singled out as a way to achieve economically viable production chains, valorize residues and coproducts, and reduce industrial waste disposal. In this sense, several alternatives aimed at the use of crude glycerol to produce fuels and chemicals by microbial fermentation have been evaluated. This review summarizes different strategies employed to produce biofuels and chemicals (1,3-propanediol, 2,3-butanediol, ethanol, n-butanol, organic acids, polyols and others) by microbial fermentation of glycerol. Initially, the industrial use of each chemical is briefly presented; then we systematically summarize and discuss the different strategies to produce each chemical, including selection and genetic engineering of producers, and optimization of process conditions to improve yield and productivity. Finally, the impact of the developments obtained until now are placed in perspective and opportunities and challenges for using crude glycerol to the development of biodiesel-based biorefineries are considered. In conclusion, the microbial fermentation of glycerol represents a remarkable alternative to add value to the biodiesel production chain helping the development of biorefineries, which will allow this biofuel to be more competitive. PMID:22809320

  9. Environmental benefits of replacing fuel oil by natural gas in the metropolitan region of Sao Paulo, Brazil

    SciTech Connect

    Kondo, S.; Assuncao, J.V. de

    1998-12-31

    The Metropolitan Region of Sao Paulo (Brazil) has a population 16.322 million people (1995 estimate) living in an area of 8,051 km2 with most of them concentrated in the city of Sao Paulo with 9.8 million people and 4.6 million cars. Although with an air quality better than some other Latin American megacities such as Mexico and Santiago do Chile, the air quality still exceeds the national air quality standards. In 2/17/1993 Brazilian Petroleum Company (PETROBRAS) and the Bolivian Petroleum Company (Yacimientos Petroliferos Fiscales Bolivianos -- YPFB) signed an agreement to bring natural gas from Bolivia to the south and southeast of Brazil. The end of the construction of the gas pipeline will be in 1999, and it will deliver 4 million Nm3/day of natural gas to COMGAS Sao Paulo State Gas Company. This amount will increase to 8.1 million Nm3/day by the year 2006, that will be sufficient to supply the Sao Paulo Metropolitan Region market need at that time. In this study an estimate of the influence in the air quality was performed supposing the substitution of fuel oil by natural gas in industry and also in diesel buses. The results showed that there will be benefits in relation to sulfur dioxide, PM10, greenhouse gases and trace elements, and negligible effects in relation to NO{sub x}, NMTOC and carbon monoxide.

  10. The balance sheet of benefits and harms of breast cancer population-based screening in Europe: outcome research, practice and future challenges.

    PubMed

    Broeders, Mireille; Paci, Eugenio

    2015-11-01

    Breast cancer screening programs are still object of harsh debate. In 2012, the Independent UK Panel reviewed the benefits and harms of mammography screening based on randomized trials and the EUROSCREEN Working Group reviewed European observational outcome studies. The conclusion was that screening programs should continue, while acknowledging that harms, such as the occurrence of false-positive results and overdiagnosis, can have a negative impact on a woman's life. Information on the balance sheet of the benefits and harms of breast cancer screening should help women and their physicians to make an informed choice. The future challenge for breast screening programs is to assess the feasibility, acceptability, effectiveness and impact of risk-based screening in order to maximize benefit-to-harm ratios. PMID:26619214

  11. Challenger

    ERIC Educational Resources Information Center

    Allday, Jonathan

    2002-01-01

    The events that led to the spectacular destruction of the Space Shuttle "Challenger" in 1986 are detailed here. They show how NASA should have heeded engineers' worries over materials problems resulting from a launch in cold weather. Suggestions are made of how pupils could also learn from this tragedy. (Contains 4 figures and 2 footnotes.)

  12. Challenger

    NASA Astrophysics Data System (ADS)

    Allday, Jonathan

    2002-09-01

    The events that led to the spectacular destruction of the Space Shuttle Challenger in 1986 are detailed here. They show how NASA should have heeded engineers' worries over materials problems resulting from a launch in cold weather. Suggestions are made of how pupils could also learn from this tragedy.

  13. Challenges

    ERIC Educational Resources Information Center

    Moore, Thomas R.

    1975-01-01

    Domestic and international challenges facing the National Society for the Prevention of Blindness are discussed; and U.S. and Russian programs in testing and correcting children's vision, developing eye safety programs in agriculture and industry, and disseminating information concerning the detection and treatment of cataracts are compared. (SB)

  14. Biodiesel biorefinery: opportunities and challenges for microbial production of fuels and chemicals from glycerol waste

    PubMed Central

    2012-01-01

    The considerable increase in biodiesel production worldwide in the last 5 years resulted in a stoichiometric increased coproduction of crude glycerol. As an excess of crude glycerol has been produced, its value on market was reduced and it is becoming a “waste-stream” instead of a valuable “coproduct”. The development of biorefineries, i.e. production of chemicals and power integrated with conversion processes of biomass into biofuels, has been singled out as a way to achieve economically viable production chains, valorize residues and coproducts, and reduce industrial waste disposal. In this sense, several alternatives aimed at the use of crude glycerol to produce fuels and chemicals by microbial fermentation have been evaluated. This review summarizes different strategies employed to produce biofuels and chemicals (1,3-propanediol, 2,3-butanediol, ethanol, n-butanol, organic acids, polyols and others) by microbial fermentation of glycerol. Initially, the industrial use of each chemical is briefly presented; then we systematically summarize and discuss the different strategies to produce each chemical, including selection and genetic engineering of producers, and optimization of process conditions to improve yield and productivity. Finally, the impact of the developments obtained until now are placed in perspective and opportunities and challenges for using crude glycerol to the development of biodiesel-based biorefineries are considered. In conclusion, the microbial fermentation of glycerol represents a remarkable alternative to add value to the biodiesel production chain helping the development of biorefineries, which will allow this biofuel to be more competitive. PMID:22809320

  15. Teaching Science with Case Studies: A National Survey of Faculty Perceptions of the Benefits and Challenges of Using Cases

    ERIC Educational Resources Information Center

    Yadav, Aman; Lundeberg, Mary; DeSchryver, Michael; Dirkin, Kathryn; Schiller, Nancy A.; Maier, Kimberly; Herreid, Clyde Freeman

    2007-01-01

    To understand more about faculty perceptions of the instructional benefits of and barriers to using case studies, the authors surveyed 101 science faculty at universities and colleges in the United States and Canada. The results provided evidence that, overall, faculty think cases have a positive impact on student learning, critical thinking, and…

  16. Teachers' Views on Digital Educational Tools in English Language Learning: Benefits and Challenges in the Turkish Context

    ERIC Educational Resources Information Center

    Çelik, Servet; Aytin, Kübra

    2014-01-01

    Despite the clear benefits provided by digital educational tools, Turkish teachers of English as a foreign language (EFL) are often seen as failing to take advantage of computing technologies in the classroom. Deficiencies in terms of teachers' digital literacies are often faulted for this omission. The majority of studies concerning Turkish…

  17. Space Shuttle main engine. NASA has not evaluated the alternate fuel turbopump costs and benefits. Report to the Administrator of the National Aeronautics and Space Administration

    NASA Astrophysics Data System (ADS)

    1993-10-01

    NASA's plans to develop an alternate high pressure fuel turbopump for the Space Shuttle's main engines were assessed by the General Accounting Office as a part of the evaluation of the Space Shuttle Safety and Obsolescence Upgrade program. The objective was to determine whether NASA has adequately analyzed cost, performance, and benefits that are expected to result from this program in comparison to other alternatives before resuming development of the alternate pump, which was suspended in 1992. The alternate fuel pump is one of five improvements being developed or planned to significantly enhance safety margins of the engines.

  18. Research Stakeholders’ Views on Benefits and Challenges for Public Health Research Data Sharing in Kenya: The Importance of Trust and Social Relations

    PubMed Central

    Jao, Irene; Kombe, Francis; Mwalukore, Salim; Bull, Susan; Parker, Michael; Kamuya, Dorcas; Molyneux, Sassy; Marsh, Vicki

    2015-01-01

    Background There is increasing recognition of the importance of sharing research data within the international scientific community, but also of the ethical and social challenges this presents, particularly in the context of structural inequities and varied capacity in international research. Public involvement is essential to building locally responsive research policies, including on data sharing, but little research has involved stakeholders from low-to-middle income countries. Methods Between January and June 2014, a qualitative study was conducted in Kenya involving sixty stakeholders with varying experiences of research in a deliberative process to explore views on benefits and challenges in research data sharing. In-depth interviews and extended small group discussions based on information sharing and facilitated debate were used to collect data. Data were analysed using Framework Analysis, and charting flow and dynamics in debates. Findings The findings highlight both the opportunities and challenges of communicating about this complex and relatively novel topic for many stakeholders. For more and less research-experienced stakeholders, ethical research data sharing is likely to rest on the development and implementation of appropriate trust-building processes, linked to local perceptions of benefits and challenges. The central nature of trust is underpinned by uncertainties around who might request what data, for what purpose and when. Key benefits perceived in this consultation were concerned with the promotion of public health through science, with legitimate beneficiaries defined differently by different groups. Important challenges were risks to the interests of study participants, communities and originating researchers through stigmatisation, loss of privacy, impacting autonomy and unfair competition, including through forms of intentional and unintentional 'misuse' of data. Risks were also seen for science. Discussion Given background structural

  19. Benefits and Challenges of Scaling Up Expansion of Marine Protected Area Networks in the Verde Island Passage, Central Philippines.

    PubMed

    Horigue, Vera; Pressey, Robert L; Mills, Morena; Brotánková, Jana; Cabral, Reniel; Andréfouët, Serge

    2015-01-01

    Locally-established marine protected areas (MPAs) have been proven to achieve local-scale fisheries and conservation objectives. However, since many of these MPAs were not designed to form ecologically-connected networks, their contributions to broader-scale goals such as complementarity and connectivity can be limited. In contrast, integrated networks of MPAs designed with systematic conservation planning are assumed to be more effective--ecologically, socially, and economically--than collections of locally-established MPAs. There is, however, little empirical evidence that clearly demonstrates the supposed advantages of systematic MPA networks. A key reason is the poor record of implementation of systematic plans attributable to lack of local buy-in. An intermediate scenario for the expansion of MPAs is scaling up of local decisions, whereby locally-driven MPA initiatives are coordinated through collaborative partnerships among local governments and their communities. Coordination has the potential to extend the benefits of individual MPAs and perhaps to approach the potential benefits offered by systematic MPA networks. We evaluated the benefits of scaling up local MPAs to form networks by simulating seven expansion scenarios for MPAs in the Verde Island Passage, central Philippines. The scenarios were: uncoordinated community-based establishment of MPAs; two scenarios reflecting different levels of coordinated MPA expansion through collaborative partnerships; and four scenarios guided by systematic conservation planning with different contexts for governance. For each scenario, we measured benefits through time in terms of achievement of objectives for representation of marine habitats. We found that: in any governance context, systematic networks were more efficient than non-systematic ones; systematic networks were more efficient in broader governance contexts; and, contrary to expectations but with caveats, the uncoordinated scenario was slightly more

  20. Benefits and Challenges of Scaling Up Expansion of Marine Protected Area Networks in the Verde Island Passage, Central Philippines

    PubMed Central

    Horigue, Vera; Pressey, Robert L.; Mills, Morena; Brotánková, Jana; Cabral, Reniel; Andréfouët, Serge

    2015-01-01

    Locally-established marine protected areas (MPAs) have been proven to achieve local-scale fisheries and conservation objectives. However, since many of these MPAs were not designed to form ecologically-connected networks, their contributions to broader-scale goals such as complementarity and connectivity can be limited. In contrast, integrated networks of MPAs designed with systematic conservation planning are assumed to be more effective—ecologically, socially, and economically—than collections of locally-established MPAs. There is, however, little empirical evidence that clearly demonstrates the supposed advantages of systematic MPA networks. A key reason is the poor record of implementation of systematic plans attributable to lack of local buy-in. An intermediate scenario for the expansion of MPAs is scaling up of local decisions, whereby locally-driven MPA initiatives are coordinated through collaborative partnerships among local governments and their communities. Coordination has the potential to extend the benefits of individual MPAs and perhaps to approach the potential benefits offered by systematic MPA networks. We evaluated the benefits of scaling up local MPAs to form networks by simulating seven expansion scenarios for MPAs in the Verde Island Passage, central Philippines. The scenarios were: uncoordinated community-based establishment of MPAs; two scenarios reflecting different levels of coordinated MPA expansion through collaborative partnerships; and four scenarios guided by systematic conservation planning with different contexts for governance. For each scenario, we measured benefits through time in terms of achievement of objectives for representation of marine habitats. We found that: in any governance context, systematic networks were more efficient than non-systematic ones; systematic networks were more efficient in broader governance contexts; and, contrary to expectations but with caveats, the uncoordinated scenario was slightly more

  1. Opportunities and challenges for developing an oilseed to renewable jet fuel industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Military and commercial aviation have expressed interest in using renewable aviation biofuels, with an initial goal of 1 billion gallons of drop-in aviation biofuels by 2018. While these fuels could come from many sources, hydrotreated renewable jet fuel (HRJ) from vegetable oils have been demonstra...

  2. Proton Exchange Membrane (PEM) Fuel Cell Status and Remaining Challenges for Manned Space-Flight Applications

    NASA Technical Reports Server (NTRS)

    Reaves, Will F.; Hoberecht, Mark A.

    2003-01-01

    The Fuel Cell has been used for manned space flight since the Gemini program. Its power output and water production capability over long durations for the mass and volume are critical for manned space-flight requirements. The alkaline fuel cell used on the Shuttle, while very reliable and capable for it s application, has operational sensitivities, limited life, and an expensive recycle cost. The PEM fuel cell offers many potential improvements in those areas. NASA Glenn Research Center is currently leading a PEM fuel cell development and test program intended to move the technology closer to the point required for manned space-flight consideration. This paper will address the advantages of PEM fuel cell technology and its potential for future space flight as compared to existing alkaline fuel cells. It will also cover the technical hurdles that must be overcome. In addition, a description of the NASA PEM fuel cell development program will be presented, and the current status of this effort discussed. The effort is a combination of stack and ancillary component hardware development, culminating in breadboard and engineering model unit assembly and test. Finally, a detailed roadmap for proceeding fiom engineering model hardware to qualification and flight hardware will be proposed. Innovative test engineering and potential payload manifesting may be required to actually validate/certify a PEM fuel cell for manned space flight.

  3. Benefits of Java

    MedlinePlus

    ... and Facts Fitness Fitness Find out more Categories Sports and Performance Training and Recovery Exercise Topics Fueling Your Workout Benefits of Physical Activity Exercise Nutrition Top Articles Man ...

  4. The challenges and benefits of a genuine partnership between Music Therapy and Neuroscience: a dialog between scientist and therapist

    PubMed Central

    Magee, Wendy L.; Stewart, Lauren

    2015-01-01

    Collaborations between neuroscience and music therapy promise many mutual benefits given the different knowledge bases, experiences and specialist skills possessed by each discipline. Primarily, music therapists deliver music-based interventions on a daily basis with numerous populations; neuroscientists measure clinical changes in ways that provide an evidence base for progressing clinical care. Although recent developments suggest that partnerships between the two can produce positive outcomes for both fields, these collaborations are not considered mainstream. The following dialog between an experienced professional from each discipline explores the potential for collaboration, as well as the misconceptions that may be preventing further synergies from developing. PMID:25983683

  5. The challenges and benefits of a genuine partnership between Music Therapy and Neuroscience: a dialog between scientist and therapist.

    PubMed

    Magee, Wendy L; Stewart, Lauren

    2015-01-01

    Collaborations between neuroscience and music therapy promise many mutual benefits given the different knowledge bases, experiences and specialist skills possessed by each discipline. Primarily, music therapists deliver music-based interventions on a daily basis with numerous populations; neuroscientists measure clinical changes in ways that provide an evidence base for progressing clinical care. Although recent developments suggest that partnerships between the two can produce positive outcomes for both fields, these collaborations are not considered mainstream. The following dialog between an experienced professional from each discipline explores the potential for collaboration, as well as the misconceptions that may be preventing further synergies from developing. PMID:25983683

  6. Nutritional, Health, and Technological Functionality of Lupin Flour Addition to Bread and Other Baked Products: Benefits and Challenges.

    PubMed

    Villarino, C B J; Jayasena, V; Coorey, R; Chakrabarti-Bell, S; Johnson, S K

    2016-01-01

    Lupin is an undervalued legume despite its high protein and dietary fiber content and potential health benefits. This review focuses on the nutritional value, health benefits, and technological effects of incorporating lupin flour into wheat-based bread. Results of clinical studies suggest that consuming lupin compared to wheat bread and other baked products reduce chronic disease risk markers; possibly due to increased protein and dietary fiber and bioactive compounds. However, lupin protein allergy has also been recorded. Bread quality has been improved when 10% lupin flour is substituted for refined wheat flour; possibly due to lupin-wheat protein cross-linking assisting bread volume and the high water-binding capacity (WBC) of lupin fiber delaying staling. Above 10% substitution appears to reduce bread quality due to lupin proteins low elasticity and the high WBC of its dietary fiber interrupting gluten network development. Gaps in understanding of the role of lupin flour in bread quality include the optimal formulation and processing conditions to maximize lupin incorporation, role of protein cross-linking, antistaling functionality, and bioactivity of its γ-conglutin protein. PMID:25675266

  7. Challenge to aviation: Hatching a leaner pterosauer. [improving commercial aircraft design for greater fuel efficiency

    NASA Technical Reports Server (NTRS)

    Moss, F. E.

    1975-01-01

    Modifications in commercial aircraft design, particularly the development of lighter aircraft, are discussed as effective means of reducing aviation fuel consumption. The modifications outlined include: (1) use of the supercritical wing; (2) generation of the winglet; (3) production and flight testing of composite materials; and, (4) implementation of fly-by-wire control systems. Attention is also given to engineering laminar air flow control, improving cargo payloads, and adapting hydrogen fuels for aircraft use.

  8. Understanding Fire Patterns and Fuel Consumption in Russian Forests: Progress and Challenges

    NASA Astrophysics Data System (ADS)

    Conard, Susan; Stocks, Brian; Cahoon, Donald; de Groot, William; Soja, Amber; Ivanova, Galina; Kukavskaya, Elena; McRae, Douglas; Ponomarev, Evgenii; Buryak, Ludmilla; Flannigan, Mike; Swetnam, Thomas; Hao, Wei Min

    2015-04-01

    Research conducted over the past 20 years has greatly changed our understanding of the extent, patterns, and impact of wildfire in the forests of Russia. The availability of remote sensing data at various scales has been essential to improvements in burned area estimates, and has allowed us to develop a new 30-year record of burned areas in Russia. Fire scar data in selected regions has provided information on fire-climate interactions over the past several centuries. And field data from experimental fires and from wildfires has provided essential information on fire behavior, fuel consumption, and ecosystem fire effects. In this presentation we discuss the historical development of improved data on burned area, fuel characterization and fuel consumption. We will emphasize the impacts of inaccuracies in source data on burned area and fire regimes, vegetation, fuels, fuel consumption, and other factors. We present model results using the Canadian BorFire to develop annual estimates of fuel consumption and emissions for the Asian part of Russia. Potential interactions of fire with large-scale atmospheric patterns appear to be an important factor in determining occurrence and timing of large fire outbreaks, and changes in these patterns are likely to drive future changes in fire regimes. Data will be presented to illustrate these effects. The presentation will conclude with a summary of the current status of knowledge and ongoing research needs.

  9. Maximizing Societal Benefits Associated With Alternative Fuel Subsidies: The Case of Plug-in Hybrid Electric Vehicles

    NASA Astrophysics Data System (ADS)

    Nazir, Samir M.

    Government seeks to improve the welfare of its citizenry and intervenes in marketplaces to maximize benefits when externalities are not captured. By analyzing how welfare changes from area to area across the country in response to the same intervention informs where government should act. This thesis analyzes the case of plug-in hybrid electric vehicles (PHEVs). PHEVs have many societal benefits, including improving national security, economic, environmental, and health advantages. The magnitude and distribution of these benefits depends on where PHEVs are deployed. This thesis develops and applies a methodology to determine if the benefits from PHEV deployment vary across the country and for ranking regions where positive PHEV consequences are likely to be maximized. The metrics in this method are proxies of key variables which predict the level of benefits in a county from the deployment of a PHEV there; they include population, health benefits from reduced ozone concentration, vehicle miles traveled per capita, existence of non-federal policies, and CO 2 intensity of electricity. By shedding light on how benefits from PHEV deployment vary across counties, this thesis seeks to better inform where to enact government interventions to maximize the benefits of this technology.

  10. The Benefits and Challenges of Having AN Open and Free Basis Satellite Data Sharing Platform in Turkey: GEZGİN

    NASA Astrophysics Data System (ADS)

    Seda Deveci, Hüsne; Koru, Aziz; Sakarya, Ufuk; Tevrizoğlu, İsmail; Teke, Mustafa; Küpçü, Ramazan; Avenoğlu, Bülent; Demirkesen, Can; Zübeyde Gürbüz, Sevgi; Feray Öztoprak, A.; Açıkgöz, İbrahim Serdar; Hakkı Demirhan, İsmail; Ömer Kozal, Ali; Efendioğlu, Mehmet; Berke, Erdinç; Fehmi Şimşek, F.; Atıl, İlkay; Kaya, Derya; Uçmak, Pınar; Ersöz, Eda; Özen, Hilal

    2016-06-01

    Turkey is a county that experiences rapid socioeconomic development, which, in turn, leads to high urbanization rates due to migration of people from rural to urban areas, many large-scale development projects (e.g. highways, dams, housing and infrastructure), and environmental problems that adversely affect agriculture, such as soil erosion and deforestation. Furthermore, Turkey lies in a region prone to natural disasters, especially earthquakes, landslides, flooding and forest fires. Successfully overcoming these challenges requires continuous monitoring to enable rapid response as well as the development of effective socioeconomic policies. In this regard, space-based earth observation (EO) systems play a critical role in the rapid acquisiton and extraction of crucial information. The first launch of the first Turkish-designed satellite, RASAT, in 2011 led to the wide-spread exploitation of space-based resources by Turkish institutions through the dissemination of EO data on an open and free basis via the GEZGIN internet portal (http://www.gezgin.gov.tr). The push for data sharing was further instigated by the nationally funded project GEOPORTAL ("Satellite Image Processing and Geoportal Development Project") and European Union FP7 project EOPOWER ("Earth Observation for Economic Empowerment"), which strove to create conditions for sustainable economic development through the increased use of Earth observation products and services for environmental applications. In this work, the technical challenges involving processing and preparing raw satellite data for dissemination as well as software design of the GEZGIN Portal will be presented.

  11. Perceived benefits and challenges for low-income mothers of having family meals with preschool-aged children: childhood memories matter.

    PubMed

    Malhotra, Khushi; Herman, Allison N; Wright, Gretchen; Bruton, Yasmeen; Fisher, Jennifer O; Whitaker, Robert C

    2013-11-01

    Eating regular family meals is associated with a lower risk of obesity among preschool-aged children. Children in lower-income households are at higher risk for obesity, but there is little information about their mothers' perceptions of family meals, and such information could improve nutrition counseling. To identify the perceived benefits and challenges of having family meals, four focus groups were conducted with 20 mothers of preschool-aged children living in low-income households in Philadelphia, PA. Three authors independently analyzed verbatim transcripts using an inductive method of open coding, and themes were established by consensus among all authors. Of the 20 mothers, 18 were black, 11 had education beyond high school, and 12 were living with an adult partner or husband. Mothers' strong childhood memories of mealtimes, both negative and positive, motivated them to have family meals because of the opportunities afforded by mealtimes to build strong relationships with their children. However, mothers also described needing help, especially from other household adults, in preparing meals and establishing calm and order with their children during mealtimes. To identify what motivates the mothers of low-income, preschool-aged children to have family meals, registered dietitians can benefit from asking about the mothers' own childhood experiences of family meals. Studies are needed to examine whether such an approach to identifying maternal motivations, when combined with practical advice about overcoming challenges with meal preparation and managing children's mealtime behavior, could lead to more frequent and nutritious family meals in this population. PMID:24144074

  12. Benefits and Challenges with Applying Unique Molecular Identifiers in Next Generation Sequencing to Detect Low Frequency Mutations

    PubMed Central

    Kou, Ruqin; Lam, Ham; Duan, Hairong; Ye, Li; Jongkam, Narisra; Chen, Weizhi; Zhang, Shifang; Li, Shihong

    2016-01-01

    Indexing individual template molecules with a unique identifier (UID) before PCR and deep sequencing is promising for detecting low frequency mutations, as true mutations could be distinguished from PCR errors or sequencing errors based on consensus among reads sharing same index. In an effort to develop a robust assay to detect from urine low-abundant bladder cancer cells carrying well-documented mutations, we have tested the idea first on a set of mock templates, with wild type and known mutants mixed at defined ratios. We have measured the combined error rate for PCR and Illumina sequencing at each nucleotide position of three exons, and demonstrated the power of a UID in distinguishing and correcting errors. In addition, we have demonstrated that PCR sampling bias, rather than PCR errors, challenges the UID-deep sequencing method in faithfully detecting low frequency mutation. PMID:26752634

  13. Facing Challenges in Differential Classical Conditioning Research: Benefits of a Hybrid Design for Simultaneous Electrodermal and Electroencephalographic Recording

    PubMed Central

    Pastor, M. Carmen; Rehbein, Maimu Alissa; Junghöfer, Markus; Poy, Rosario; López, Raul; Moltó, Javier

    2015-01-01

    Several challenges make it difficult to simultaneously investigate central and autonomous nervous system correlates of conditioned stimulus (CS) processing in classical conditioning paradigms. Such challenges include, for example, the discrepant requirements of electroencephalography (EEG) and electrodermal activity (EDA) recordings with regard to multiple repetitions of conditions and sufficient trial duration. Here, we propose a MultiCS conditioning set-up, in which we increased the number of CSs, decreased the number of learning trials, and used trials of short and long durations for meeting requirements of simultaneous EEG–EDA recording in a differential aversive conditioning task. Forty-eight participants underwent MultiCS conditioning, in which four neutral faces (CS+) were paired four times each with aversive electric stimulation (unconditioned stimulus) during acquisition, while four different neutral faces (CS−) remained unpaired. When comparing after relative to before learning measurements, EEG revealed an enhanced centro-posterior positivity to CS+ vs. CS− during 368–600 ms, and subjective ratings indicated CS+ to be less pleasant and more arousing than CS−. Furthermore, changes in CS valence and arousal were strong enough to bias subjective ratings when faces of CS+/CS− identity were displayed with different emotional expression (happy, angry) in a post-experimental behavioral task. In contrast to a persistent neural and evaluative CS+/CS− differentiation that sustained multiple unreinforced CS presentations, electrodermal differentiation was rapidly extinguished. Current results suggest that MultiCS conditioning provides a promising paradigm for investigating pre–post-learning changes under minimal influences of extinction and overlearning of simple stimulus features. Our data also revealed methodological pitfalls, such as the possibility of occurring artifacts when combining different acquisition systems for central and peripheral

  14. Porting fluid and kinetic plasma models for space plasma physics to heterogeneous architectures: Benefits and Challenges (Invited)

    NASA Astrophysics Data System (ADS)

    Germaschewski, K.; Raeder, J.; Ruhl, H.

    2010-12-01

    Advances in processor technology provide the opportunity to simulate space plasma dynamics at unprecedented resolution. As processor clock speeds have begun to plateau in recent years, new technologies have emerged that maintain exponential growth in computational capability, in particular multi-core processors and heterogeneous approaches to computing, e.g., the STI Cell processor and general purpose GPUs. We will discuss two projects that aim at porting existing codes to efficiently run on heterogeneous processors. The Particle Simulation Code (PSC) is a 3D fully electromagnetic particle-in-cell code, solving the kinetic plasma equations, including a collision operator. This code is applied to problems requiring a kinetic model, like particle acceleration and modeling the microscopic structure of a reconnecting current sheets. We will discuss the performance gains enabled by porting the code to NVIDIA's GPU CUDA programming environment, as well as the challenges in exploiting the full capabilities of GPUs for the current deposition step. OpenGGCM is a community global magnetosphere model. The main computational challenge is the solution of the 3D MHD equations which are discretized using finite-difference / finite-volume. We ported this code to the Cell processor using a novel code generator. This approach allows us to specify the discretized equations in near-symbolic form as a stencil computation, and then have highly-optimized code be generated automatically. From the same description we are able to generate plain C code, C code with SIMD/SSE2 extensions and code for the Cell processor, yielding significant performance gains. We will also present first results of a new extension to the code generator that creates CUDA code for GPUs.

  15. The Euratom Fast Collar (EFC): A Safeguards Instrument Design to Address Future Fuel Measurement Challenges

    SciTech Connect

    Evans, Louise; Swinhoe, Martyn T.; Menlove, Howard O.; Browne, Michael C.

    2012-08-13

    Summary of this presentation: (1) EFC instrument design for {sup 235}U verification measurements issued to EURATOM to issue a call for commercial tender; (2) Achieved a fast (Cd mode) measurement with less than 2% relative uncertainty in the doubles neutron counting rate in 10 minutes using a standard source strength; (3) Assay time in fast mode consistent with the needs of an inspector; (4) Extended to realistic calibration range for modern fuel designs - Relatively insensitive to gadolinia content for fuel designs with up to 32 burnable poison rods and 15 wt % gadolinia concentration, which is a realistic maximum for modern PWR fuel; (5) Improved performance over the standard thermal neutron collar with greater than twice the efficiency of the original design; (6) Novel tube pattern to reduce the impact of accidental pile-up; and (7) Joint test of prototype unit - EURATOM-LANL.

  16. Exploiting Nutritional Value of Staple Foods in the World's Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum.

    PubMed

    Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

    2015-01-01

    Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered. PMID:27417755

  17. Fuel ethanol production from lignocellulose: a challenge for metabolic engineering and process integration.

    PubMed

    Zaldivar, J; Nielsen, J; Olsson, L

    2001-07-01

    With industrial development growing rapidly, there is a need for environmentally sustainable energy sources. Bioethanol (ethanol from biomass) is an attractive, sustainable energy source to fuel transportation. Based on the premise that fuel bioethanol can contribute to a cleaner environment and with the implementation of environmental protection laws in many countries, demand for this fuel is increasing. Efficient ethanol production processes and cheap substrates are needed. Current ethanol production processes using crops such as sugar cane and corn are well-established; however, utilization of a cheaper substrate such as lignocellulose could make bioethanol more competitive with fossil fuel. The processing and utilization of this substrate is complex, differing in many aspects from crop-based ethanol production. One important requirement is an efficient microorganism able to ferment a variety of sugars (pentoses, and hexoses) as well as to tolerate stress conditions. Through metabolic engineering, bacterial and yeast strains have been constructed which feature traits that are advantageous for ethanol production using lignocellulose sugars. After several rounds of modification/evaluation/modification, three main microbial platforms, Saccharomyces cerevisiae, Zymomonas mobilis, and Escherichia coli, have emerged and they have performed well in pilot studies. While there are ongoing efforts to further enhance their properties, improvement of the fermentation process is just one of several factors-that needs to be fully optimized and integrated to generate a competitive lignocellulose ethanol plant. PMID:11499926

  18. A case study of the implementation of an ergonomics improvement committee in a Brazilian hospital--Challenges and benefits.

    PubMed

    Bolis, Ivan; Sznelwar, Laerte I

    2016-03-01

    This article discusses the creation of an improvement committee (IC) to implement policies aimed at improving working conditions in a public health institution in the city of São Paulo. Suggestions were proposed for future implementations of this organizational mechanism, pursuant to the presentation of the process of its formation and the main results achieved. The findings led to the conclusion that good outcomes require autonomy and support from management, and the adoption of effective measures to improve and legitimize the improvement committee's existence. Another important issue is facilitating worker involvement and creating a locus for dialog among people with different visions within the organization. Thus, two approaches converge: a top-down approach in which policies are defined and improvement actions are actually implemented based on a general outlook of the production and work system, and a bottom-up approach specific to employees who are also engaged in improvement policies and in putting them into practice. It is also possible to point out problems and opportunities arising from actual work situations to the higher levels of management. This kind of approach fits with macroergonomics, because it integrates strategy, organization and work issues. It is possible to discuss the benefits of this approach for companies and provide conditions for workers to engage effectively in these processes. In conclusion, these proposals can be considered from an emancipatory perspective, given that different actors should be able to codetermine working conditions and work content, thus directly influencing their individual and collective experiences. The support and commitment of upper management are essential elements of success in maximizing the effectiveness of this organizational approach. PMID:26464035

  19. Coming Out in Class: Challenges and Benefits of Active Learning in a Biology Classroom for LGBTQIA Students

    PubMed Central

    Cooper, Katelyn M.; Brownell, Sara E.

    2016-01-01

    As we transition our undergraduate biology classrooms from traditional lectures to active learning, the dynamics among students become more important. These dynamics can be influenced by student social identities. One social identity that has been unexamined in the context of undergraduate biology is the spectrum of lesbian, gay, bisexual, transgender, queer, intersex, and asexual (LGBTQIA) identities. In this exploratory interview study, we probed the experiences and perceptions of seven students who identify as part of the LGBTQIA community. We found that students do not always experience the undergraduate biology classroom to be a welcoming or accepting place for their identities. In contrast to traditional lectures, active-learning classes increase the relevance of their LGBTQIA identities due to the increased interactions among students during group work. Finally, working with other students in active-learning classrooms can present challenges and opportunities for students considering their LGBTQIA identity. These findings indicate that these students’ LGBTQIA identities are affecting their experience in the classroom and that there may be specific instructional practices that can mitigate some of the possible obstacles. We hope that this work can stimulate discussions about how to broadly make our active-learning biology classes more inclusive of this specific population of students. PMID:27543636

  20. Coming Out in Class: Challenges and Benefits of Active Learning in a Biology Classroom for LGBTQIA Students.

    PubMed

    Cooper, Katelyn M; Brownell, Sara E

    2016-01-01

    As we transition our undergraduate biology classrooms from traditional lectures to active learning, the dynamics among students become more important. These dynamics can be influenced by student social identities. One social identity that has been unexamined in the context of undergraduate biology is the spectrum of lesbian, gay, bisexual, transgender, queer, intersex, and asexual (LGBTQIA) identities. In this exploratory interview study, we probed the experiences and perceptions of seven students who identify as part of the LGBTQIA community. We found that students do not always experience the undergraduate biology classroom to be a welcoming or accepting place for their identities. In contrast to traditional lectures, active-learning classes increase the relevance of their LGBTQIA identities due to the increased interactions among students during group work. Finally, working with other students in active-learning classrooms can present challenges and opportunities for students considering their LGBTQIA identity. These findings indicate that these students' LGBTQIA identities are affecting their experience in the classroom and that there may be specific instructional practices that can mitigate some of the possible obstacles. We hope that this work can stimulate discussions about how to broadly make our active-learning biology classes more inclusive of this specific population of students. PMID:27543636

  1. Living well with HIV in Nigeria? Stigma and survival challenges preventing optimum benefit from an ART clinic.

    PubMed

    Aransiola, Joshua; Imoyera, Winifred; Olowookere, Samuel; Zarowsky, Christina

    2014-03-01

    Thirty years into the HIV pandemic, the interactions of stigma, social and economic survival, and clinical interventions continue to be key to understanding and managing HIV at both personal and societal levels. With antiretroviral therapy, HIV is increasingly a chronic condition requiring lifelong treatment, near-perfect adherence, and support from both social networks and formal services. This study asked: is stigma still a significant problem for people living with HIV (PLHIV) who have secured access to antiretrovirals (ARVs)? How do PLHIV accessing ARVs in Nigeria experience the social, economic and health service supports intended to address their needs? What are the concerns and challenges of PLHIV and health workers regarding these supports? What are the implications for approaches to stigma and discrimination? This qualitative study at the Antiretroviral (ART) Clinic of the Osogbo State Hospital, Osun State, Nigeria involved in-depth interviews with 15 PLHIV who have been attending the clinic for at least one year, and three health workers. The results reveal both the diversity among even a small number of patients, and persistent cross-cutting themes of stigma, discrimination, poverty, and the psychological impacts of insecure livelihoods and well-intentioned but ultimately stigmatizing supports such as selective food parcels. Both population-based interventions against stigma and poverty, as well as micro-level, contextualized attention to patients', families' and health workers' fear of social exclusion and infection at a clinic and community level are needed if patients - and society - are to live well with HIV in Nigeria. PMID:24569837

  2. Integral Healthcare: The Benefits and Challenges of Integrating Complementary and Alternative Medicine with a Conventional Healthcare Practice

    PubMed Central

    Ross, Christina L.

    2009-01-01

    Today’s medicine is in the midst of an undeniable crisis. Calls to reform healthcare are in the forefront of economic and political discussions worldwide. Economic pressures reduce the amount of time physicians can spend with patients contributing to burnout among medical staff and endangering the patient iatrogenically. Politicians are getting involved as the public is calling for more affordable healthcare. A new paradigm must be embraced in order to address all aspects of this dilemma. It is clear that science and technology have resulted in vastly improved understanding, diagnosis, and treatment of disease, but the emphasis on science and technology to the exclusion of other elements of healing has also served to limit the development of a model that humanizes healthcare. The healing of a patient must include more than the biology and chemistry of their physical body; by necessity, it must include the mental, emotional and spiritual aspects. Because of these challenges, the development of an integral healthcare system that is rooted in appropriate regulation and supported by rigorous scientific evidence is the direction that many models of integrative healthcare are moving towards in the 21st century. PMID:21614160

  3. Shallow Offshore Tsunami Sedimentary Deposits: Challenges and Benefits with examples from the Eastern Mediterranean and northern Red Sea

    NASA Astrophysics Data System (ADS)

    Goodman Tchernov, B. N.

    2014-12-01

    Tsunamigenic deposits preserved in the offshore, shallow (<30msl) uppershelf environment has been suggested as a possible resource for improving the understanding of tsunami sedimentological dynamics and producing a more detailed paleotsunami record. On one hand, this zone is advantageous due to its relatively lower susceptibility to anthropogenic disturbance and certain types of erosion. However, the added complications of collection difficulties, marine dynamics and disturbance, and heterogeneity may prove this archive less desirable and accessible. Recent results of a multitude of offshore shallow coring efforts in the eastern Mediterranean and northern Red Sea will be presented and discussed with regard to the question of the usefulness, limitations, and advantages of these offshore records. Broadly summarized, like their terrestrial counterparts, the offshore archive requires extensive attention to the local background conditions and characteristics of the surrounding contributing sources in order to recognize, interpret, and mine the information contained within them. While some tsunami indicator criteria remain the 'rule', their expression and appearance inter and intrasite can vary considerably and therefore the ability to recognize them challenging. Ultimately, as more results are shared from recent modern analogues and compared with sedimentological anomalies with possible tsunamigenic characteristics within the offshore sedimentological record, the better and more precisely these deposits will be defined and interpreted.

  4. Modeling and managing urban water demand through smart meters: Benefits and challenges from current research and emerging trends

    NASA Astrophysics Data System (ADS)

    Cominola, A.; Giuliani, M.; Castelletti, A.; Piga, D.; Rizzoli, A. E.

    2015-12-01

    Urban population growth, climate and land use change are expected to boost residential water demand in urban contexts in the next decades. In such a context, developing suitable demand-side management strategies is essential to meet future water demands, pursue water savings, and reduce the costs for water utilities. Yet, the effectiveness of water demand management strategies (WDMS) relies on our understanding of water consumers' behavior, their consumption habits, and the water use drivers. While low spatial and temporal resolution water consumption data, as traditionally gathered for billing purposes, hardly support this understanding, the advent of high-resolution, smart metering technologies allowed for quasi real-time monitoring water consumption at the single household level. This, in turn, is advancing our ability in characterizing consumers' behavior, modeling, and designing user-oriented residential water demand management strategies. Several water smart metering programs have been rolled-out in the last two decades worldwide, addressing one or more of the following water demand management phases: (i) data gathering, (ii) water end-uses characterization, (iii) user modeling, (iv) design and implementation of personalized WDMS. Moreover, the number of research studies in this domain is quickly increasing and big economic investments are currently being devoted worldwide to smart metering programs. With this work, we contribute the first comprehensive review of more than 100 experiences in the field of residential water demand modeling and management, and we propose a general framework for their classification. We revise consolidated practices, identify emerging trends and highlight the challenges and opportunities for future developments given by the use of smart meters advancing residential water demand management. Our analysis of the status quo of smart urban water demand management research and market constitutes a structured collection of information

  5. Schools of the Pacific Rainfall Climate Experiment: The Benefits and Challenges of Student Participation in Scientific Research Programs

    NASA Astrophysics Data System (ADS)

    Morrissey, M. L.; Postawko, S.

    2005-12-01

    The Schools of the Pacific Rainfall Climate Experiment (SPaRCE) is a cooperative field project involving elementary, middle school, high school, college and trade school students, along with personnel from Pacific Island meteorological services, in expanding and enhancing the climate observation network across the Pacific Basin. The goals of the program are to: 1. foster interest and increase awareness among students, teachers, and local island meteorologists as to the importance of cooperation between nations in investigating potential climate change, 2. to educate students and teachers as to the importance of rainfall (particularly in the Pacific region) to climate studies, 3. to increase the observations of climate variable across the Pacific, and to incorporate the collected observations into a comprehensive Pacific database to be used for climate research purposes 4. to make a major contribution to the global climate research effort by collecting and analyzing Pacific climate data, 5. and to encourage scientific and cultural exchange. The SPaRCE program has been working with students, teachers, and meteorological service personnel on various Pacific islands and atolls since 1991. Much of the data collected has been incorporated into the Comprehensive Pacific Rainfall Database and has been used as verification data for several satellite rainfall studies. In addition, several students who got involved in the SPaRCE program at their school have gone on to work at their local meteorological service upon graduation. Significant advances in the technological capabilities in most of the Pacific island countries have taken place over the years. These advances have been both a help and a hindrance in getting schools involved in making accurate, reliable, long-term climate observations and getting students excited about analyzing these data. One challenge that has remained fairly constant over the years is that of teacher turn-over in these developing island nations.

  6. Quantification of uncertainty associated with United States high resolution fossil fuel CO2 emissions: updates, challenges and future plans

    NASA Astrophysics Data System (ADS)

    Gurney, K. R.; Chandrasekaran, V.; Mendoza, D. L.; Geethakumar, S.

    2010-12-01

    The Vulcan Project has estimated United States fossil fuel CO2 emissions at the hourly time scale and at spatial scales below the county level for the year 2002. Vulcan is built from a wide variety of observational data streams including regulated air pollutant emissions reporting, traffic monitoring, energy statistics, and US census data. In addition to these data sets, Vulcan relies on a series of modeling assumptions and constructs to interpolate in space, time and transform non-CO2 reporting into an estimate of CO2 combustion emissions. The recent version 2.0 of the Vulcan inventory has produced advances in a number of categories with particular emphasis on improved temporal structure. Onroad transportation emissions now avail of roughly 5000 automated traffic count monitors allowing for much improved diurnal and weekly time structure in our onroad transportation emissions. Though the inventory shows excellent agreement with independent national-level CO2 emissions estimates, uncertainty quantification has been a challenging task given the large number of data sources and numerous modeling assumptions. However, we have now accomplished a complete uncertainty estimate across all the Vulcan economic sectors and will present uncertainty estimates as a function of space, time, sector and fuel. We find that, like the underlying distribution of CO2 emissions themselves, the uncertainty is also strongly lognormal with high uncertainty associated with a relatively small number of locations. These locations typically are locations reliant upon coal combustion as the dominant CO2 source. We will also compare and contrast Vulcan fossil fuel CO2 emissions estimates against estimates built from DOE fuel-based surveys at the state level. We conclude that much of the difference between the Vulcan inventory and DOE statistics are not due to biased estimation but mechanistic differences in supply versus demand and combustion in space/time.

  7. World Biofuels Production Potential Understanding the Challenges to Meeting the U.S. Renewable Fuel Standard

    SciTech Connect

    Sastri, B.; Lee, A.

    2008-09-15

    This study by the U.S. Department of Energy (DOE) estimates the worldwide potential to produce biofuels including biofuels for export. It was undertaken to improve our understanding of the potential for imported biofuels to satisfy the requirements of Title II of the 2007 Energy Independence and Security Act (EISA) in the coming decades. Many other countries biofuels production and policies are expanding as rapidly as ours. Therefore, we modeled a detailed and up-to-date representation of the amount of biofuel feedstocks that are being and can be grown, current and future biofuels production capacity, and other factors relevant to the economic competitiveness of worldwide biofuels production, use, and trade. The Oak Ridge National Laboratory (ORNL) identified and prepared feedstock data for countries that were likely to be significant exporters of biofuels to the U.S. The National Renewable Energy Laboratory (NREL) calculated conversion costs by conducting material flow analyses and technology assessments on biofuels technologies. Brookhaven National Laboratory (BNL) integrated the country specific feedstock estimates and conversion costs into the global Energy Technology Perspectives (ETP) MARKAL (MARKet ALlocation) model. The model uses least-cost optimization to project the future state of the global energy system in five year increments. World biofuels production was assessed over the 2010 to 2030 timeframe using scenarios covering a range U.S. policies (tax credits, tariffs, and regulations), as well as oil prices, feedstock availability, and a global CO{sub 2} price. All scenarios include the full implementation of existing U.S. and selected other countries biofuels policies (Table 4). For the U.S., the most important policy is the EISA Title II Renewable Fuel Standard (RFS). It progressively increases the required volumes of renewable fuel used in motor vehicles (Appendix B). The RFS requires 36 billion (B) gallons (gal) per year of renewable fuels by 2022

  8. Successes and Challenges in the Resale of Alternative Fuel Vehicles: July 2001 - March 2002

    SciTech Connect

    Not Available

    2002-05-01

    This report provides the outcome of Dorfman & O'Neal's effort to examine the resale market for automobiles as it relates to the resale of late-model, original equipment manufacture (OEM), alternative fuel vehicles. Auctions provide an exceptionally rapid, effective, and efficient market for the transfer of property between buyers and sellers at reasonable prices. The first automobile auction in the United States was successful because used cars were in reasonably constant supply, were uniformly packaged, and were easily graded for quality. Also, the auction had sufficient volume to significantly lower the handling and transaction costs for wholesalers and dealers. To this day, the automobile auction industry conducts business primarily with registered wholesalers and dealers. Except for the U.S. General Services Administration (GSA) auctions and some consignment auctions, nearly all automobile auctions are closed to the public. The auction system represents a near-perfect market, validated by the lack of statistical price differences in value of specific model cars between various regions of the country. However, specialty cars may be subject to arbitrage. The buyer purchases the vehicle believing that it can be sold immediately at a profit in another region. A variety of vehicle pricing services are available to serve the consumer and the wholesale automobile industry. Each has a different philosophy for collecting, analyzing, and reporting data. ''The Automobile Lease Guide'' (ALG) is clearly the authority on vehicle residual values. Auction companies continue to apply automated technologies to lower transaction costs. Automated technologies are the only way to track the increasing number of transactions in the growing industry. Nevertheless, people-to-people relationships remain critical to the success of all auction companies. Our assessment is that everyone in the secondary automobile market is aware of alternative fuel vehicles (AFVs) and is interested to

  9. Radioactive waste partitioning and transmutation within advanced fuel cycles: Achievements and challenges

    NASA Astrophysics Data System (ADS)

    Salvatores, M.; Palmiotti, G.

    2011-01-01

    If nuclear power becomes a sustainable source of energy, a safe, robust, and acceptable solution must be pursued for existing and projected inventories of high-activity, long-lived radioactive waste. Remarkable progress in the field of geological disposal has been made in the last two decades. Some countries have reached important milestones, and geological disposal (of spent fuel) is expected to start in 2020 in Finland and in 2022 in Sweden. In fact, the licensing of the geological repositories in both countries is now entering into its final phase. In France, disposal of intermediate-level waste (ILW) and vitrified high-level waste (HLW) is expected to start around 2025, according to the roadmap defined by an Act of Parliament in 2006. In this context, transmutation of part of the waste through use of advanced fuel cycles, probably feasible in the coming decades, can reduce the burden on the geological repository. This article presents the physical principle of transmutation and reviews several strategies of partitioning and transmutation (P&T). Many recent studies have demonstrated that the impact of P&T on geological disposal concepts is not overwhelmingly high. However, by reducing waste heat production, a more efficient utilization of repository space is likely. Moreover, even if radionuclide release from the waste to the environment and related calculated doses to the population are only partially reduced by P&T, it is important to point out that a clear reduction of the actinide inventory in the HLW definitely reduces risks arising from less probable evolutions of a repository (i.e., an increase of actinide mobility in certain geochemical situations and radiological impact by human intrusion).

  10. Radioactive Waste Partitioning and Transmutation within Advanced Fuel Cycles: Achievements and Challenges

    SciTech Connect

    M. Salvatores; G. Palmiotti

    2011-01-01

    If nuclear power should become a sustainable source of energy, a safe, robust and acceptable solution must be pursued for existing and projected inventories of high-activity, long-lived radioactive waste. Remarkable progress in the last two decades has been made in the field of geological disposal. Some countries have reached important milestones and geological disposal (of spent fuel) is expected to start in 2020 in Finland and in 2022 in Sweden and in fact the licensing of the geological repositories in both countries is now entering into their final phases. In France disposal of Intermediate Level Wastes (ILW) and vitrified High Level Wastes (HLW) is expected to start around 2025, according to the roadmap defined by a Parliament Act in 2006. In this context, transmutation of part of the waste through use of advanced fuel cycles, probably feasible in the coming decades, has the potential of reducing the burden on the geological repository. This article presents the physical principle of transmutation and reviews several strategies of P&T (Partitioning and Transmutation). Many recent studies have demonstrated that the impact of P&T on geological disposal concepts is not overwhelmingly high. However, by reducing waste heat production a more efficient utilization of repository space is likely. Moreover, even if radionuclide release from the waste to the environment and related calculated doses to the population are only partially reduced by P&T, it is important to point out that a clear reduction of the actinide inventory in the High Level Waste definitely reduces risks arising from less probable evolutions of a repository, i.e. increase of actinide mobility in certain geochemical situations and radiological impact by human intrusion.

  11. Conductive Education: Benefits and Challenges

    ERIC Educational Resources Information Center

    Ratliffe, Katherine T.; Sanekane, Cindy

    2009-01-01

    Conductive education (CE) is an intensive, holistic approach to the education of people with physical disabilities that recognizes that teaching and learning are related to the emotional, cognitive, and physical aspects of individuals. Despite its popularity in the United States and throughout the world, research has not demonstrated a clear…

  12. Radioactive waste partitioning and transmutation within advanced fuel cycles: Achievements and Challenges

    SciTech Connect

    M. Salvatores; G. Palmiotti

    2011-01-01

    In the last decades, numerous studies have been performed in order to identify appropriate “Partitioning and Transmutation” (P&T) strategies, aiming to the reduction of the burden on a geological storage (see, among many others, Salvatores, 2005). P&T strategies are very powerful and unique tools to reduce drastically the radiotoxicity level of the wastes and to reduce the time needed to reach the reference level (from ~100,000 years to few hundred years, i.e. comparable to the period in which technological and engineering means allow reasonably to control the radioactivity confinement). Moreover, P&T allows, in principle, also the reduction of the residual heat in a geological repository, with a potential significant impact on the repository size and characteristics. The first requirement of P&T strategies is the deployment of spent fuel reprocessing techniques (aqueous or dry), which are both in the continuity of today technologies (e.g. as implemented at La Hague in France, where Pu is separated up to 99.9 %) or which represent innovative, adapted approaches (e.g. pyrochemistry). The requirement is to extend the performance of Pu separation to 99.9 % also to Np, Am and Cm kept together or separated and in any case decontaminated from the lanthanides as much as possible. The separated TRU should then be “transmuted” (or “burned”) in a neutron field. The essential mechanism is to fission them, transforming them into much shorter lived or stable fission products. However, the fission process is always in competition with other processes, and, in particular, with neutron capture, which does eliminate isotope A, but transforms it into isotope A+1, which can still be radioactive. Isotope A+1 can in turn be fissioned or transmuted into isotope A+2, and so on. The neutron field has to be provided by a fission reactor. The requirement for this (dedicated) reactor is to be able to privilege the fission process with respect to the capture process and to be able

  13. Analysis of the FeCrAl Accident Tolerant Fuel Concept Benefits during BWR Station Blackout Accidents

    SciTech Connect

    Robb, Kevin R

    2015-01-01

    Iron-chromium-aluminum (FeCrAl) alloys are being considered for fuel concepts with enhanced accident tolerance. FeCrAl alloys have very slow oxidation kinetics and good strength at high temperatures. FeCrAl could be used for fuel cladding in light water reactors and/or as channel box material in boiling water reactors (BWRs). To estimate the potential safety gains afforded by the FeCrAl concept, the MELCOR code was used to analyze a range of postulated station blackout severe accident scenarios in a BWR/4 reactor employing FeCrAl. The simulations utilize the most recently known thermophysical properties and oxidation kinetics for FeCrAl. Overall, when compared to the traditional Zircaloy-based cladding and channel box, the FeCrAl concept provides a few extra hours of time for operators to take mitigating actions and/or for evacuations to take place. A coolable core geometry is retained longer, enhancing the ability to stabilize an accident. Finally, due to the slower oxidation kinetics, substantially less hydrogen is generated, and the generation is delayed in time. This decreases the amount of non-condensable gases in containment and the potential for deflagrations to inhibit the accident response.

  14. Fuel cell commercialization issues for light-duty vehicle applications

    NASA Astrophysics Data System (ADS)

    Borroni-Bird, Christopher E.

    The major challenges facing fuel cells in light-duty vehicle applications relate to the high cost of the fuel cell stack components (membrane, electro-catalyst and bipolar plate) which dictate that new manufacturing processes and materials must be developed. Initially, the best fuel for a mass market light-duty vehicle will probably not be the best fuel for the fuel cell (hydrogen); refueling infrastructure and energy density concerns may demand the use of an on-board fuel processor for petroleum-based fuels since this will increase customer acceptance. The use of fuel processors does, however, reduce the fuel cell system's efficiency. Moreover, if such fuels are used then the emissions benefit associated with fuel cells may come with a significant penalty in terms of added complexity, weight, size and cost. However, ultimately, fuel cells powered by hydrogen do promise to be the most efficient and cleanest of automotive powertrains.

  15. Sharing the tracks to good tucker: identifying the benefits and challenges of implementing community food programs for Aboriginal communities in Victoria.

    PubMed

    Murray, Margaret; Bonnell, Emily; Thorpe, Sharon; Browne, Jennifer; Barbour, Liza; MacDonald, Catherine; Palermo, Claire

    2014-01-01

    Food insecurity is a significant issue in the Victorian Aboriginal population, contributing to the health disparity and reduced life expectancy. Community food programs are a strategy used to minimise individual level food insecurity, with little evidence regarding their effectiveness for Aboriginal populations. The aim of this study was to explore the role of community food programs operating for Aboriginal people in Victoria and their perceived influence on food access and nutrition. Semistructured interviews were conducted with staff (n=23) from a purposive sample of 18 community food programs across Victoria. Interviews explored the programs' operation, key benefits to the community, challenges and recommendations for setting up a successful community food program. Results were analysed using a qualitative thematic approach and revealed three main themes regarding key factors for the success of community food programs: (1) community food programs for Aboriginal people should support access to safe, affordable, nutritious food in a socially and culturally acceptable environment; (2) a community development approach is essential for program sustainability; and (3) there is a need to build the capacity of community food programs as part of a strategy to ensure sustainability. Community food programs may be an effective initiative for reducing food insecurity in the Victorian Aboriginal population. PMID:25116591

  16. State-of-the-art of mass production: challenges for low-cost and application benefits of high-performances small-pitch IR detectors

    NASA Astrophysics Data System (ADS)

    Bercier, Emmanuel; Dessus, Jean Luc; Manissadjian, Alain; Tribolet, Philippe

    2008-04-01

    HgCdTe (Mercury Cadmium Telluride / MCT) staring arrays for infrared detection do show constant improvements regarding their compactness and performances. New detectors are now proposed offering system solutions in the different IR wavebands and taking advantage of the latest technology improvements as well as MCT performance advantages and cost reduction. Based on 20 years of experience in 50μm to 15μm pitch Infrared (IR) detector production, the challenge of mass production of low-cost small-pixel pitch detectors are reviewed, from the IR chip manufacturing including detection material, hybridization, ROIC, to the integration in final packing. Taking advantage of its simple well known existing process, then the analyzes of all technological steps adapted to small pitch IR detector are presented, in terms of product performance, reliability, process statistics and capability in order to achieve high yield and low product cost. Answers given the low-cost small-pitch IR detector mass productions finally give benefits to application in terms of high performance, cost reduction, extended life time, and on the field system Life Cycle Support Among these new detectors, one can find the family of 15 μm pixel pitch detectors a TV format (640 x 512) integrated in dedicated tactical Dewars, taking advantages on last development in coolers manufacturing and Dewar assembly.

  17. MODELING HEAT TRANSFER IN SPENT FUEL TRANSFER CASK NEUTRON SHIELDS – A CHALLENGING PROBLEM IN NATURAL CONVECTION

    SciTech Connect

    Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.

    2010-07-18

    In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 10-15 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper proposes that there may be reliable CFD approaches to the transfer cask problem, specifically coupled steady-state solvers or unsteady simulations; however, both of these solutions take significant computational effort. Segregated (uncoupled) steady state solvers that were tested did not

  18. Genetic Evaluation and Use of Chromosome Microarray in Patients with Isolated Heart Defects: Benefits and Challenges of a New Model in Cardiovascular Care.

    PubMed

    Helm, Benjamin M; Freeze, Samantha L

    2016-01-01

    also provide perspective regarding the benefits and challenges that lie ahead for this model in the clinical setting. PMID:27379245

  19. Genetic Evaluation and Use of Chromosome Microarray in Patients with Isolated Heart Defects: Benefits and Challenges of a New Model in Cardiovascular Care

    PubMed Central

    Helm, Benjamin M.; Freeze, Samantha L.

    2016-01-01

    . We also provide perspective regarding the benefits and challenges that lie ahead for this model in the clinical setting. PMID:27379245

  20. Balancing benefits and costs in a 4°C world: the need for and challenges of natural-social science dialogue

    NASA Astrophysics Data System (ADS)

    Kopp, R. E.

    2012-12-01

    Making wise policy decisions regarding mitigation, adaptation and geoengineering requires fair assessments of the risks of both action and inaction. Such assessments necessitate dialogue between natural and social scientists. Recent attempts by the U.S. government to estimate the social cost of carbon (SCC) for use in balancing the benefits and costs of proposed mitigatory regulations highlight some of the challenges involved. Among them: (1) Scale: The costs and benefits of adaptation decisions generally take place locally, while the benefits of mitigation accrue globally. Most studies to inform adaptation decision have, quite reasonably, taken place at the local scale, but this has left globally aggregate estimates of climate risk in a fairly tenuous state, engaging only a handful of economists. More accurate assessments, needed for making critical policy decisions as we approach a 4°C world, will require both better top-down analyses and a better framework for integrating bottom-up analyses. (2) Historical validation: Integrated assessment models have not been subject to validation studies, such as the historical runs used to test physical climate models. Conducting such studies for impact analyses will require the integration and further development of statistical analyses of the human impact of past and ongoing climate change. If models don't work for a 0.8°C world, there's no reason to think they'll work for a 4°C world. (3) Looking beyond a 4°C world: A world that reaches 4°C in this century may exceed it in the next century; and even if temperature is stabilized, understanding the economic impacts of 4°C warming will require more than the current approach of extrapolating from 2°C impacts. Natural scientists and social scientists need to work together to estimate damage calibration points for considerably warmer conditions. Recent work on the loss of physiologically habitable regions in a >8°C warmer world is a rare step in this direction (Sherwood

  1. A collaborative effort to apply the evidence-based review process to the field of nutrition: Challenges, benefits and lessons learned

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evidence-based systematic reviews on dietary assessment and nutritional interventions are becoming increasingly common, but are relatively new compared to other applications. Concerns remain that systematic reviews of nutrition topics pose several unique challenges. Such challenges are illuminated...

  2. Automotive Fuel Processor Development and Demonstration with Fuel Cell Systems

    SciTech Connect

    Nuvera Fuel Cells

    2005-04-15

    The potential for fuel cell systems to improve energy efficiency and reduce emissions over conventional power systems has generated significant interest in fuel cell technologies. While fuel cells are being investigated for use in many applications such as stationary power generation and small portable devices, transportation applications present some unique challenges for fuel cell technology. Due to their lower operating temperature and non-brittle materials, most transportation work is focusing on fuel cells using proton exchange membrane (PEM) technology. Since PEM fuel cells are fueled by hydrogen, major obstacles to their widespread use are the lack of an available hydrogen fueling infrastructure and hydrogen's relatively low energy storage density, which leads to a much lower driving range than conventional vehicles. One potential solution to the hydrogen infrastructure and storage density issues is to convert a conventional fuel such as gasoline into hydrogen onboard the vehicle using a fuel processor. Figure 2 shows that gasoline stores roughly 7 times more energy per volume than pressurized hydrogen gas at 700 bar and 4 times more than liquid hydrogen. If integrated properly, the fuel processor/fuel cell system would also be more efficient than traditional engines and would give a fuel economy benefit while hydrogen storage and distribution issues are being investigated. Widespread implementation of fuel processor/fuel cell systems requires improvements in several aspects of the technology, including size, startup time, transient response time, and cost. In addition, the ability to operate on a number of hydrocarbon fuels that are available through the existing infrastructure is a key enabler for commercializing these systems. In this program, Nuvera Fuel Cells collaborated with the Department of Energy (DOE) to develop efficient, low-emission, multi-fuel processors for transportation applications. Nuvera's focus was on (1) developing fuel processor

  3. Management of Legacy Spent Nuclear Fuel Wastes at the Chalk River Laboratories: The Challenges and Innovative Solutions Implemented - 13301

    SciTech Connect

    Schruder, Kristan; Goodwin, Derek

    2013-07-01

    AECL's Fuel Packaging and Storage (FPS) Project was initiated in 2004 to retrieve, transfer, and stabilize an identified inventory of degraded research reactor fuel that had been emplaced within in-ground 'Tile Hole' structures in Chalk River Laboratories' Waste Management Area in the 1950's and 60's. Ongoing monitoring of the legacy fuel storage conditions had identified that moisture present in the storage structures had contributed to corrosion of both the fuel and the storage containers. This prompted the initiation of the FPS Project which has as its objective to design, construct, and commission equipment and systems that would allow for the ongoing safe storage of this fuel until a final long-term management, or disposition, pathway was available. The FPS Project provides systems and technologies to retrieve and transfer the fuel from the Waste Management Area to a new facility that will repackage, dry, safely store and monitor the fuel for a period of 50 years. All equipment and the new storage facility are designed and constructed to meet the requirements for Class 1 Nuclear Facilities in Canada. (authors)

  4. The electrolyte challenge for a direct methanol-air polymer electrolyte fuel cell operating at temperatures up to 200 C

    NASA Technical Reports Server (NTRS)

    Savinell, Robert; Yeager, Ernest; Tryk, Donald; Landau, Uziel; Wainright, Jesse; Gervasio, Dominic; Cahan, Boris; Litt, Morton; Rogers, Charles; Scherson, Daniel

    1993-01-01

    Novel polymer electrolytes are being evaluated for use in a direct methanol-air fuel cell operating at temperatures in excess of 100 C. The evaluation includes tests of thermal stability, ionic conductivity, and vapor transport characteristics. The preliminary results obtained to date indicate that a high temperature polymer electrolyte fuel cell is feasible. For example, Nafion 117 when equilibrated with phosphoric acid has a conductivity of at least 0.4 Omega(exp -1)cm(exp -1) at temperatures up to 200 C in the presence of 400 torr of water vapor and methanol vapor cross over equivalent to 1 mA/cm(exp 2) under a one atmosphere methanol pressure differential at 135 C. Novel polymers are also showing similar encouraging results. The flexibility to modify and optimize the properties by custom synthesis of these novel polymers presents an exciting opportunity to develop an efficient and compact methanol fuel cell.

  5. Meeting future exhaust emissions standards using natural gas as a vehicle fuel: Lessons learned from the natural gas vehicle challenge `92

    SciTech Connect

    Rimkus, W.A.; Larsen, R.P.

    1992-09-01

    The Natural Gas Vehicle Challenge `92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated exhaust constituents. Nine of the student-modified trucks passed the current levels of exhaust emission standards, and some exceeded the strictest future emissions standards envisioned by the US Environmental Protection Agency. Factors in achieving good emissions control using natural gas are summarized, and observations concerning necessary components of a successful emissions control strategy are presented.

  6. Meeting future exhaust emissions standards using natural gas as a vehicle fuel: Lessons learned from the natural gas vehicle challenge '92

    SciTech Connect

    Rimkus, W.A.; Larsen, R.P.

    1992-01-01

    The Natural Gas Vehicle Challenge '92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated exhaust constituents. Nine of the student-modified trucks passed the current levels of exhaust emission standards, and some exceeded the strictest future emissions standards envisioned by the US Environmental Protection Agency. Factors in achieving good emissions control using natural gas are summarized, and observations concerning necessary components of a successful emissions control strategy are presented.

  7. An external peer review of the U.S. Department of Energy`s assessment of ``damages and benefits of the fuel cycles: Estimation methods, impacts, and values``. Final report

    SciTech Connect

    Not Available

    1993-08-09

    The need for better assessments of the ``external`` benefits and costs of environmental effects of various fuel cycles was identified during the development of the National Energy Strategy. The growing importance of this issue was emphasized by US Department of Energy (DOE) management because over half of the states were already pursuing some form of social costing in electricity regulation and a well-established technical basis for such decisions was lacking. This issue was identified as a major area of controversy--both scientifically and politically--in developing energy policies at the state and national level. In 1989, the DOE`s Office of Domestic and International Energy Policy commissioned a study of the external environmental damages and benefits of the major fuel cycles involved in electric power generation. Over the next 3-year period, Oak Ridge National Laboratory and Resources for the Future conducted the study and produced a series of documents (fuel cycle documents) evaluating the costs of environmental damages of the coal, oil, natural gas, biomass, hydroelectric, and nuclear fuel cycles, as well as the Background Document on methodological issues. These documents described work that took almost 3 years and $2.5 million to complete and whose implications could be far reaching. In 1992, the Secretary of Energy sought advice on the overall concepts underlying the studies and the means employed to estimate environmental externalities. He asked the Secretary of Energy`s Advisory Board to undertake a peer review of the fuel cycle studies and encouraged the Board to turn to outside expertise, as needed.

  8. Assessment of costs and benefits of flexible and alternative fuel use in the U.S. transportation sector. Technical report fourteen: Market potential and impacts of alternative fuel use in light-duty vehicles -- A 2000/2010 analysis

    SciTech Connect

    1996-01-01

    In this report, estimates are provided of the potential, by 2010, to displace conventional light-duty vehicle motor fuels with alternative fuels--compressed natural gas (CNG), liquefied petroleum gas (LPG), methanol from natural gas, ethanol from grain and from cellulosic feedstocks, and electricity--and with replacement fuels such as oxygenates added to gasoline. The 2010 estimates include the motor fuel displacement resulting both from government programs (including the Clean Air Act and EPACT) and from potential market forces. This report also provides an estimate of motor fuel displacement by replacement and alterative fuels in the year 2000. However, in contrast to the 2010 estimates, the year 2000 estimate is restricted to an accounting of the effects of existing programs and regulations. 27 figs., 108 tabs.

  9. Exploiting Nutritional Value of Staple Foods in the World’s Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum

    PubMed Central

    Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

    2015-01-01

    Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered. PMID:27417755

  10. Energy Switching Threshold for Climatic Benefits

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Cao, L.; Caldeira, K.

    2013-12-01

    Climate change is one of the great challenges facing humanity currently and in the future. Its most severe impacts may still be avoided if efforts are made to transform current energy systems (1). A transition from the global system of high Greenhouse Gas (GHG) emission electricity generation to low GHG emission energy technologies is required to mitigate climate change (2). Natural gas is increasingly seen as a choice for transitions to renewable sources. However, recent researches in energy and climate puzzled about the climate implications of relying more energy on natural gas. On one hand, a shift to natural gas is promoted as climate mitigation because it has lower carbon per unit energy than coal (3). On the other hand, the effect of switching to natural gas on nuclear-power and other renewable energies development may offset benefits from fuel-switching (4). Cheap natural gas is causing both coal plants and nuclear plants to close in the US. The objective of this study is to measure and evaluate the threshold of energy switching for climatic benefits. We hypothesized that the threshold ratio of energy switching for climatic benefits is related to GHGs emission factors of energy technologies, but the relation is not linear. A model was developed to study the fuel switching threshold for greenhouse gas emission reduction, and transition from coal and nuclear electricity generation to natural gas electricity generation was analyzed as a case study. The results showed that: (i) the threshold ratio of multi-energy switching for climatic benefits changes with GHGs emission factors of energy technologies. (ii)The mathematical relation between the threshold ratio of energy switching and GHGs emission factors of energies is a curved surface function. (iii) The analysis of energy switching threshold for climatic benefits can be used for energy and climate policy decision support.