WorldWideScience

Sample records for activation energy barriers

  1. Energy barriers in patterned media

    NARCIS (Netherlands)

    de Vries, Jeroen

    2013-01-01

    Due to the fact that thermal activation aids in overcoming the energy barrier, the required field for reversal varies from instance to instance for the same island. This thermally induced switching field distribution can be used to determine the difference in energy barrier of magneticallyweak and

  2. Energy barrier to decoherence

    International Nuclear Information System (INIS)

    Mizel, Ari; Mitchell, M. W.; Cohen, Marvin L.

    2001-01-01

    We propose a ground-state approach to realizing quantum computers. This scheme is time-independent and inherently defends against decoherence by possessing an energy barrier to excitation. We prove that our time-independent qubits can perform the same algorithms as their time-dependent counterparts. Advantages and disadvantages of the time-independent approach are described. A model involving quantum dots is provided for illustration

  3. Survey of the Relationship Between Activity Energy Expenditure Metabolic Equivalents and Barrier Factors of Physical Activity in the Elderly in Kashan

    OpenAIRE

    Sadrollahi, Ali; Khalili, Zahra; Pour Nazari, Robab; Mohammadi, Majid; Ahmadi Khatir, Maryam; Mossadegh, Najima

    2016-01-01

    Background Physical activity in the elderly is influenced by aspects of aging that cause personal, mental, environmental, and social changes. Increases in factors that are barriers to activity cause physical energy expenditure to decrease. Objectives The aim of the present study was to survey the relationship between energy expenditure in metabolic equivalent units (MET) and factors that are barriers to physical activity in elderly people in Kashan, Iran Methods This is a descriptive analysis...

  4. Origins and implications of temperature-dependent activation energy barriers for dislocation nucleation in face-centered cubic metals

    International Nuclear Information System (INIS)

    Warner, D.H.; Curtin, W.A.

    2009-01-01

    The linking of atomistic simulations of stress-driven processes to experimentally observed mechanical behavior via the computation of activation energy barriers is a topic of intense current research. Using dislocation nucleation from a crack tip as the reaction process, long-time multiscale molecular dynamics simulations show that the activation barrier can exhibit significant temperature dependence. Using an analytic model for the nucleation process and computing the relevant material properties (elastic constants and stacking fault energies), the temperature dependence is shown to arise primarily from the temperature dependence of the material parameters for both Al and Ni. After thermally activated emission of the first partial dislocation, there is then a competition between two other thermally activated processes: twinning and full dislocation emission. Because the activation barriers depend on temperature, this transition is more complex than usually envisioned. Simulations in Al reveal that a transition from twinning to full dislocation emission back to twinning occurs with increasing temperature, which is counter to traditional metallurgical wisdom. Temperature-dependent activation energies are thus essential to accurate understanding and prediction of those phenomena that control fracture and deformation in metals at realistic loading rates.

  5. Enershield : energy saving air barriers

    Energy Technology Data Exchange (ETDEWEB)

    Hallihan, D. [Enershield Industries Ltd., Edmonton, AB (Canada)

    2008-07-01

    Enershield Industries is a leader in air barrier technology and provides solution for the Canadian climate. This presentation described the advantages of air barriers and the impact of rising energy costs. An air barrier is used to separate areas of differing environments and makes existing building systems more efficient. This presentation discussed how an air barrier works. It also identified how Enershield Industries calculates energy savings. It described air barrier applications and those who use barrier technology. These include the commercial and industrial sector as well as the personnel and retail sector. Barrier technology can be used for cold storage; vehicle and equipment washes; food processing; and environmental separation. Features and benefits such as the ability to create seal, acoustic insulation, and long term durability were also discussed. Last, the presentation addressed model selection and design criteria issues. Design criteria that were presented included a discussion of acoustic installation, articulating nozzles, scroll cased fans, and structural frame. Other design criteria presented were galvanized frames, telescopic sliders, and off the shelf parts. It was concluded that the ability to reduce energy consumption and enhance employee/client comfort is beneficial to the employer as well as to the employee. figs.

  6. Barriers for recess physical activity

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper

    2014-01-01

    BACKGROUND: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender...... differences in children's perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. METHODS: Data were collected through 17 focus groups (at 17 different schools...... this study, we recommend promoting recess physical activity through a combination of actions, addressing barriers within the natural, social, physical and organizational environment....

  7. Temperature dependence of the distribution of the thermally activated energy barriers in Tl2Ba2CaCu2O8 film

    International Nuclear Information System (INIS)

    Ren, C.; Lin, F.Y.; Ding, S.Y.; Li, Z.M.; Aruna, S.A.; Qiu, L.; Yao, X.X.; Yan, S.L.; Si, M.S.

    1999-01-01

    The effects of frequency and ac amplitude on ac susceptibility have been measured for a thin Tl 2 Ba 2 CaCu 2 O 8 film in the range 100 Hz-100 kHz in magnetic field 0.52 T. A phenomenological equation with an asymmetrical distribution of thermally activated energy barriers has been used to analyse these frequency and amplitude dependences of the ac susceptibility χ(ω,h ac ) in the vicinity of the peak temperature of χ''. We obtain the effective energy barrier U against amplitude h ac (current density j): U h ac -0.38 . This U(j) relationship shows that the flux lines are in the 3D collective creep regime. Therefore, we conclude that the effective energy barrier is in fact an average of the barrier's distribution, and the distribution function is a distinguished asymmetrical one in this 3D collective creep regime. (author)

  8. Circularly polarized antennas for active holographic imaging through barriers

    Science.gov (United States)

    McMakin, Douglas L [Richland, WA; Severtsen, Ronald H [Richland, WA; Lechelt, Wayne M [West Richland, WA; Prince, James M [Kennewick, WA

    2011-07-26

    Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

  9. Highway renewable energy : photovoltaic noise barriers

    Science.gov (United States)

    2017-07-01

    Highway photovoltaic noise barriers (PVNBs) represent the combination of noise barrier systems and photovoltaic systems in order to mitigate traffic noise while simultaneously producing renewable energy. First deployed in Switzerland in 1989, PVNBs a...

  10. Institutional distributed energy interconnection barriers

    International Nuclear Information System (INIS)

    Castelaz, S.A.

    2002-01-01

    This PowerPoint presentation provided an introduction to Encorp Inc., a leading provider of network technology and infrastructure management solutions for the distributed energy market. Encorp develops and markets software and hardware technology solutions for communications, control and networking of distributed energy. It is developing and implementing real-time, distributed energy-focused solutions for a wide variety of applications through new products and services which are technology neutral, and easily networked. Encorp controls more than 500 MW of distributed power with a total of 127 customers. This paper reviewed 3 barriers (regulatory, contractual/tariffs, and business practices) based on US experience. The challenge remaining is to determine if microgrids can be used effectively, and to determine the limitations of bi-directional power flows. The key issues regarding how end-users can share the costs and maximize on the benefits of distributed energy resources include: standby service charges, departing load charges, regulatory uncertainty, rate class degradation, lack of incentives for utility cost reduction, and lack of ability to create experimental tariffs. tabs., figs

  11. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the barriers'' literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  12. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the ``barriers`` literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  13. Barriers in the energy of deformed nuclei

    Directory of Open Access Journals (Sweden)

    V. Yu. Denisov

    2014-06-01

    Full Text Available Interaction energy between two nuclei considering to their deformations is studied. Coulomb and nuclear in-teraction energies, as well as the deformation energies of both nuclei, are taken into account at evaluation of the interaction energy. It is shown that the barrier related to the interaction energy of two nuclei depends on the de-formations and the height of the minimal barrier is evaluated. It is obtained that the heavier nucleus-nucleus sys-tems have large deformation values at the lowest barrier. The difference between the barrier between spherical nuclei and the lowest barrier between deformed nuclei increases with the mass and the charge of the interacting nuclei.

  14. Shakeoff Ionization near the Coulomb Barrier Energy

    Science.gov (United States)

    Sharma, Prashant; Nandi, T.

    2017-11-01

    We measure the projectile K x-ray spectra as a function of the beam energies around the Coulomb barrier in different collision systems. The energy is scanned in small steps around the barrier aiming to explore the nuclear effects on the elastically scattered projectile ions. The variation of the projectile x-ray energy with the ion-beam energies exhibits an unusual increase in between the interaction barrier and fusion barrier energies. This additional contribution to the projectile ionization can be attributed to the shakeoff of outer-shell electrons of the projectile ions due to the sudden nuclear recoil (˜10-21 sec ) caused by the attractive nuclear potential, which gets switched on near the interaction barrier energy. In the sudden approximation limit, the theoretical shakeoff probability calculation due to the nuclear recoil explains the observed data well. In addition to its fundamental interest, such processes can play a significant role in dark matter detection through the possible mechanism of x-ray emissions, where the weakly interacting massive particle-nucleus elastic scattering can lead to the nuclear-recoil-induced inner-shell vacancy creations. Furthermore, the present work may provide new prospects for atomic physics research at barrier energies as well as provide a novel technique to perform barrier distribution studies for two-body systems.

  15. Ion activation energy delivered to wounds by atmospheric pressure dielectric-barrier discharges: sputtering of lipid-like surfaces

    International Nuclear Information System (INIS)

    Babaeva, Natalia Yu; Kushner, Mark J; Ning Ning; Graves, David B

    2012-01-01

    The application of atmospheric pressure plasmas to human tissue has been shown to have therapeutic effects for wound healing and in treatment of skin diseases. These effects are attributed to production of UV photon fluxes, electric fields and beneficial radicals which intersect with biological reaction chains, and to energetic ions bombarding the surface. In this paper we report on results from a computational investigation of the ion energy and angular distributions (IEADs) in a dielectric-barrier discharge sustained in air incident directly on cell membranes for small dry and wet wounds in human skin. We found that ion energies in excess of 20-30 eV can be delivered onto cell membranes of dry wounds, and up to 60 eV onto the liquid interface of the wet wound. The details of the IEADs depend on the orientation of the cell membrane and on the relative location of the plasma streamer to the wound. Using results from a molecular dynamics simulation of ion sputter probabilities of typical lipid-like material, we show that prolonged exposure of the cell membrane to such IEADs can produce significant carbon removal. (paper)

  16. Ion activation energy delivered to wounds by atmospheric pressure dielectric-barrier discharges: sputtering of lipid-like surfaces

    Science.gov (United States)

    Babaeva, Natalia Yu; Ning, Ning; Graves, David B.; Kushner, Mark J.

    2012-03-01

    The application of atmospheric pressure plasmas to human tissue has been shown to have therapeutic effects for wound healing and in treatment of skin diseases. These effects are attributed to production of UV photon fluxes, electric fields and beneficial radicals which intersect with biological reaction chains, and to energetic ions bombarding the surface. In this paper we report on results from a computational investigation of the ion energy and angular distributions (IEADs) in a dielectric-barrier discharge sustained in air incident directly on cell membranes for small dry and wet wounds in human skin. We found that ion energies in excess of 20-30 eV can be delivered onto cell membranes of dry wounds, and up to 60 eV onto the liquid interface of the wet wound. The details of the IEADs depend on the orientation of the cell membrane and on the relative location of the plasma streamer to the wound. Using results from a molecular dynamics simulation of ion sputter probabilities of typical lipid-like material, we show that prolonged exposure of the cell membrane to such IEADs can produce significant carbon removal.

  17. Renewable energy costs, potentials, barriers: Conceptual issues

    International Nuclear Information System (INIS)

    Verbruggen, Aviel; Fischedick, Manfred; Moomaw, William; Weir, Tony; Nadai, Alain; Nilsson, Lars J.; Nyboer, John; Sathaye, Jayant

    2010-01-01

    Renewable energy can become the major energy supply option in low-carbon energy economies. Disruptive transformations in all energy systems are necessary for tapping widely available renewable energy resources. Organizing the energy transition from non-sustainable to renewable energy is often described as the major challenge of the first half of the 21st century. Technological innovation, the economy (costs and prices) and policies have to be aligned to achieve full renewable energy potentials, and barriers impeding that growth need to be removed. These issues are also covered by IPCC's special report on renewable energy and climate change to be completed in 2010. This article focuses on the interrelations among the drivers. It clarifies definitions of costs and prices, and of barriers. After reviewing how the third and fourth assessment reports of IPCC cover mitigation potentials and commenting on definitions of renewable energy potentials in the literature, we propose a consistent set of potentials of renewable energy supplies.

  18. Physical protection system using activated barriers

    International Nuclear Information System (INIS)

    Timm, R.E.; Zinneman, T.E.; Haumann, J.R.; Flaugher, H.A.; Reigle, D.L.

    1984-03-01

    The Argonne National Laboratory has recently installed an activated barrier, the Access Denial System, to upgrade its security. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The Argonne National Laboratory is the first Department of Energy facility to use this device. Recent advancements in electronic components provide the total system support that makes the use of an activated barrier viable and desirable. The premise of an activated barrier is that it is deployed after a positive detection of an adversary is made and before the adversary can penetrate vital area. To accomplish this detection, sophisticated alarms, assessment, and communications must be integrated into a system that permits a security inspector to make a positive evaluation and to activate the barrier. The alarm sensor locations are selected to provide protection in depth. Closed circuit television is used with components that permit multiple video frames to be stored for automated, priority-based playback to the security inspector. Further, algorithms permit look-ahead surveillance of vital areas so that the security inspector can activate the access denial system in a timely manner and not be restricted to following the adversaries' penetration path(s)

  19. Investing in Energy Efficiency. Removing the Barriers

    International Nuclear Information System (INIS)

    2004-01-01

    Investing in improving energy efficiency has the clear advantages of reducing energy costs, improving security of supply and mitigating the environmental impacts of energy use. And still, many viable opportunities for higher energy efficiency are not tapped because of the existence of numerous barriers to such investments. These lost opportunities imply costs to the individual energy consumers and to the society as a whole and they are particularly important in economies in transition. This report identifies various types of barriers for making energy efficiency investments (be they of legal, administrative, institutional or financial nature), mainly in buildings, district heating and efficient lighting. The role of various bodies and organisations for the facilitation of energy efficiency investments is analysed, from public authorities and regulators to banks and international financing institutions

  20. Nuclear energy technology transfer: the security barriers

    International Nuclear Information System (INIS)

    Rinne, R.L.

    1975-08-01

    The problems presented by security considerations to the transfer of nuclear energy technology are examined. In the case of fusion, the national security barrier associated with the laser and E-beam approaches is discussed; for fission, the international security requirements, due to the possibility of the theft or diversion of special nuclear materials or sabotage of nuclear facilities, are highlighted. The paper outlines the nuclear fuel cycle and terrorist threat, examples of security barriers, and the current approaches to transferring technology. (auth)

  1. Faculty Perceptions about Barriers to Active Learning

    Science.gov (United States)

    Michael, Joel

    2007-01-01

    Faculty may perceive many barriers to active learning in their classrooms. Four groups of participants in a faculty development workshop were asked to list their perceived barriers to active learning. Many of the problems identified were present on more than one list. The barriers fall into three categories: student characteristics, issues…

  2. Barriers to physical activity among working mothers.

    Science.gov (United States)

    Dombrowski, Jill J

    2011-04-01

    Working mothers experience several barriers to physical activity. If these barriers can be identified by occupational health nurses and they can partner with working mothers to reduce these perceived barriers, the health of these workers can be improved and chronic disease risk prevented. The purpose of this study was to measure the effect of self-regulatory efficacy on physical activity among working mothers and to describe specific barriers to physical activity. The Barriers Specific Self-Efficacy Scale (BARSE) and the Kaiser Physical Activity Survey (KPAS) were used to measure the variables. Self-regulatory efficacy was found to be a strong predictor of physical activity in a diverse sample of working mothers who did not meet current recommendations for physical activity. Occupational health nurses can use these findings to design programs for groups and for counseling individuals. Copyright 2011, SLACK Incorporated.

  3. Market and Policy Barriers to Energy Storage Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Bhatnagar, Dhruv [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Currier, Aileen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hernandez, Jacquelynne [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ma, Ookie [Dept. of Energy (DOE), Washington DC (United States) Office of Energy Efficiency and Renewable Energy; Kirby, Brendan [Consultant

    2013-09-01

    Electric energy storage technologies can provide numerous grid services; there are a number of factors that restrict their current deployment. The most significant barrier to deployment is high capital costs, though several recent deployments indicate that capital costs are decreasing and energy storage may be the preferred economic alternative in certain situations. However, a number of other market and regulatory barriers persist, limiting further deployment. These barriers can be categorized into regulatory barriers, market (economic) barriers, utility and developer business model barriers, cross-cutting barriers and technology barriers.

  4. Energy analysis of vehicle-to-cable barrier impacts.

    Science.gov (United States)

    2013-06-01

    An accident reconstruction technique was developed for estimating the energy absorbed during an impact with a cable barrier system as well as the initial impact velocity. The kinetic energy absorbed during a cable barrier system impact is comprised o...

  5. Barriers to Physical Activity on University Student

    Science.gov (United States)

    Jajat; Sultoni, K.; Suherman, A.

    2017-03-01

    The purpose of the research is to analyze the factors that become barriers to physical activity in university students based on physical activity level. An internet-based survey was conducted. The participants were 158 University students from Universitas Pendidikan Indonesia. Barriers to Physical Activity Quiz (BPAQ) were used to assessed the factors that become barriers to physical activity in university students. IPAQ (short form) were used to assessed physical activity level. The results show there was no differences BPAQ based on IPAQ level. But when analyzed further based on seven factors barriers there are differences in factors “social influence and lack of willpower” based IPAQ level. Based on this it was concluded that the “influence from other and lack of willpower” an inhibiting factor on students to perform physical activity.

  6. Barriers for realisation of energy savings in buildings; Barrierer for realisering af energibesparelser i bygninger

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, O.M.

    2004-07-01

    Many years' efforts within the energy labelling area have shown large saving potentials in heating and use of electricity in buildings. At the same time it has been proved that these saving potentials, even when economically advantageous, only are cashed to a limited extent. The reason to this is ascribed to barriers that meet the individual building owner who wants to start saving energy. Most barriers are known and a lot of these have been sought overcome for some time. The questions are how many barriers still exist, have new barriers arisen and the character of these barriers. On this background the objective of this survey has been to concretize and study the barriers, which are blocking reasonable energy savings. Focus has especially been on barriers for realisation of heating savings, but through a general evaluation of energy savings of barriers other forms of energy saving methods have been taken into consideration. Special interest has been directed towards houses, typically one family houses, which are affected by the Energy Labelling Scheme. The concept barriers include all kinds of barriers, also barriers that not are acknowledged as barriers by the individual house owner, or that on closer inspection turn out to be something else than actual barriers. This note suggests an alternative inertia model, in order to create an idea of the inertness characteristic of the many house owners who understand the message but fail to act on it. (BA)

  7. Perceived barriers to physical activity among Polish adolescents.

    Science.gov (United States)

    Jodkowska, Maria; Mazur, Joanna; Oblacińska, Anna

    2015-01-01

    To identify barriers to physical activity (PA) for adolescents according to the gender and age and examine the association between these barriers and youths' physical activity. 3346 students aged 10-16 years (1759 girls) took part in the cross-sectional, nationally representative study. For this paper the dataset was created from adolescents who reported perceived barriers to PA, N = 2300, (1259 girls), range 13-16 years. Barriers and physical activity (MVPA) were analysed for all participants, as well as by gender, age group and place of residence. Multiple regression analysis was used to examine the relationships between perceived barriers and physical inactivity for all and than separately for boys and girls. Lack of energy, lack of time and lack of support were three of the five barriers reported by more than 40% of adolescents, statistically more likely by girls than boys and older youth than younger. For boys - lack of time (OR = 2.56; CI = 1.66-3.96), lack of skills (OR = 2.35; CI = 1.94-3.95), lack of willpower (OR = 1.71, CI = 1.05-2.80) and lack of support (OR = 1.64, CI = 1.11-2.41) were the predictors contributing to low level of PA. For girls lack of skills (OR = 3.16, CI = 1.62-6.18), lack of energy (OR = 1.84, CI = 1.14-2.96), lack of support (OR = 1.64, CI = 1.07-2.54) and lack of time (OR = 1.61,CI = 1.00-2.60) were positively and statistically significant associated with physical inactivity. 1. Perceived barriers to physical activity among adolescents have strong negative impact on recommended PA level. For girls lack of skills is the strongest predictor of low PA, for boys - lack of time. 2. Identification more precisely barriers to physical activity among adolescents will enable to developed more effective interventions in high-risk populations.

  8. Empirical investigation of energy efficiency barriers in Italian manufacturing SMEs

    International Nuclear Information System (INIS)

    Trianni, Andrea; Cagno, Enrico; Worrell, Ernst; Pugliese, Giacomo

    2013-01-01

    The paper identifies and evaluates barriers to industrial energy efficiency through the investigation of 48 manufacturing Small and Medium-sized Enterprises (SMEs) in Northern Italy. The research provides interesting suggestions both for enterprises and energy policy-makers. Firstly, economic and information barriers are perceived as the major obstacles to the adoption of energy-efficient technologies, whilst behavioural barriers do not seem to affect enterprises very much. Nonetheless, despite what declared, the most relevant barriers are the lack of interest in energy efficiency and the existence of other priorities, thus showing that decision-makers tend to downgrade energy efficiency to a marginal issue. Furthermore, perceived barriers do not take place exclusively in implementing energy-efficient technologies, but, with comparable importance, also in generating the interest and knowledge of the opportunities. Moreover, the study highlights that relevant differences can be appreciated for both perceived and real barriers even among SMEs, that thus should not be bundled together. In addition to that, other factors affect barriers, stimulating future research: indeed, lower real barriers can be observed with higher complexity of the production, high variability of the demand and strong competitors. -- Highlights: ► Evidence of existing misalignments between perceived and real barriers to the adoption of energy-efficient technologies. ► Relevance of barriers to the generation of interest towards energy efficiency. ► Evidence of firm's size (within SMEs) and energy expenditures on barriers to energy efficiency. ► Importance, for energy efficiency barriers, of avoid bundling SMEs as a whole. ► Preliminary evidence of factors related to supply chain complexity affecting barriers to energy efficiency.

  9. Energy education: breaking up the rational energy use barriers

    International Nuclear Information System (INIS)

    Dias, R.A.; Mattos, C.R.; Balestieri, J.A.P.

    2004-01-01

    Human development is associated directly or indirectly with the energy use, and because of this the energetic sources were dealt with in the recent past, as fully available to human necessities. The reality shows that the energy availability, considering the non-renewable sources, is limited, and beyond that, the exploration, the processing and the use of energy impose considerable impacts on the environment. There is not a system which operates with no losses and without imposing changes to the environment. Therefore, the energy conservation incorporates the concepts and the actions applied to the research of sustainable balance between nature and the energy availability and use. Such actions can be presented both in the short term, in which the energy system is close to a collapse, or in the medium/long term, in which those responsible for the energy policies are concerned with the structure of the socio-economic development. Such a situation requires more responsibility in the treatment of energy questions, mainly through education, which represents long-term investments. This paper discusses barriers that are present in the projects applied to energy conservation, by making clear that education is one of the best ways to transform the human behavior in for the rational use of energy

  10. Magnetization reversal processes of single nanomagnets and their energy barrier

    International Nuclear Information System (INIS)

    Krone, P.; Makarov, D.; Albrecht, M.; Schrefl, T.; Suess, D.

    2010-01-01

    Micromagnetic simulations were performed to investigate the influence of geometry and magnetic anisotropy constant on energy barrier and magnetization reversal mechanism of individual bits important for the bit patterned media concept in magnetic data storage. It is shown that dependency of the energy barrier on magnetic and geometric properties of bits can be described by an analytical approach in the case of quasi-coherent magnetization rotation process. However, when the bit size exceeds a critical size, for which an incoherent magnetization reversal is preferred, the analytical approach becomes invalid and no self-consistent theory is available. By systematically investigating the influence of bit size on the magnetization reversal mode, it was found that the transition from quasi-coherent to incoherent magnetization reversal mode can still be described analytically if an activation volume is considered instead of the bit volume. In this case, the nucleation volume is an important parameter determining thermal stability of the bit. If the volume of the bit is larger than twice the activation volume, the energy barrier stays nearly constant; with further increase in bit size, no gain in thermal stability can be achieved.

  11. Understanding Motivators and Barriers to Physical Activity

    Science.gov (United States)

    Patay, Mary E.; Patton, Kevin; Parker, Melissa; Fahey, Kathleen; Sinclair, Christina

    2015-01-01

    The purpose of this study was to understand the factors that influence physical activity among year-round residents in an isolated summer resort community. Specifically, we explored the personal, environmental, social, and culture-specific perceived motivators and barriers to physical activity. Participants were formally interviewed about their…

  12. Addressing barriers to low carbon energy

    International Nuclear Information System (INIS)

    Berry, Fiona; Dunstan, Chris

    2012-01-01

    Full text: Two energy solutions gaining attention are cogeneration and trigeneration, mostly fuelled by natural gas, although other renewable sources can be used, such as sewage, agricultural waste and municipal waste. Trigeneration has become increasingly popular in Australia's urban centres as a relatively cost-effective means to cut the carbon-intensity of energy supply by more than half compared to traditional coal- fired electricity. Some examples of trigeneration projects include the City of Sydney's planned 360 megawatt trigeneration networks by 2030, the University of Technology Sydney's campus master plan and the six star Green Star Commonwealth Bank Place building in Sydney. Trigeneration and cogeneration can present opportunities such as addressing the issue of rising peak demand, which is a major driver for the current $9 billion per annum of network infrastructure spending. They can also face barriers. For example, depending on the current state of the network, additional network costs can be required to accommodate trigeneration. Furthermore, under the current National Electricity Market regulations and conventions, challenges do exist to timely and financially viable connection to the grid. Here we present two examples of barriers to trigeneration and cogeneration and solutions being considered and implemented. The University of Technology Sydney campus master plan is underway, with approximately 100,000sq.m of floor area being built by 2019 and includes plans for trigeneration. During the master planning phase of development, the university considered small trigeneration units in individual buildings in order to reduce the carbon intensity of electricity supply and deliver high ratings under Green Star ratings. When considering connecting trigeneration with the grid at multiple buildings on an individual basis, a number of barriers were encountered by UTS. The largest barrier was appropriate charging for connecting to and using the grid. However

  13. Barriers to Physical Activity in East Harlem, New York

    Directory of Open Access Journals (Sweden)

    Ashley M. Fox

    2012-01-01

    Full Text Available Background. East Harlem is an epicenter of the intertwining epidemics of obesity and diabetes in New York. Physical activity is thought to prevent and control a number of chronic illnesses, including diabetes, both independently and through weight control. Using data from a survey collected on adult (age 18+ residents of East Harlem, this study evaluated whether perceptions of safety and community-identified barriers were associated with lower levels of physical activity in a diverse sample. Methods. We surveyed 300 adults in a 2-census tract area of East Harlem and took measurements of height and weight. Physical activity was measured in two ways: respondents were classified as having met the weekly recommended target of 2.5 hours of moderate physical activity (walking per week (or not and reporting having engaged in at least one recreational physical activity (or not. Perceived barriers were assessed through five items developed by a community advisory board and perceptions of neighborhood safety were measured through an adapted 7-item scale. Two multivariate logistic regression models with perceived barriers and concerns about neighborhood safety were modeled separately as predictors of engaging in recommended levels of exercise and recreational physical activity, controlling for respondent weight and sociodemographic characteristics. Results. The most commonly reported perceived barriers to physical activity identified by nearly half of the sample were being too tired or having little energy followed by pain with exertion and lack of time. Multivariate regression found that individuals who endorsed a greater number of perceived barriers were less likely to report having met their weekly recommended levels of physical activity and less likely to engage in recreational physical activity controlling for covariates. Concerns about neighborhood safety, though prevalent, were not associated with physical activity levels. Conclusions. Although

  14. Activation Energy

    Science.gov (United States)

    Gadeken, Owen

    2002-01-01

    Teaming is so common in today's project management environment that most of us assume it comes naturally. We further assume that when presented with meaningful and challenging work, project teams will naturally engage in productive activity to complete their tasks. This assumption is expressed in the simple (but false) equation: Team + Work = Teamwork. Although this equation appears simple and straightforward, it is far from true for most project organizations whose reality is a complex web of institutional norms based on individual achievement and rewards. This is illustrated by the very first successful team experience from my early Air Force career. As a young lieutenant, I was sent to Squadron Officer School, which was the first in the series of Air Force professional military education courses I was required to complete during my career. We were immediately formed into teams of twelve officers. Much of the course featured competition between these teams. As the most junior member of my team, I quickly observed the tremendous pressure to show individual leadership capability. At one point early in the course, almost everyone in our group was vying to become the team leader. This conflict was so intense that it caused us to fail miserably in our first outdoor team building exercise. We spent so much time fighting over leadership that we were unable to complete any of the events on the outdoor obstacle course. This complete lack of success was so disheartening to me that I gave our team little hope for future success. What followed was a very intense period of bickering, conflict, and even shouting matches as our dysfunctional team tried to cope with our early failures and find some way to succeed. British physician and researcher Wilfred Bion (Experiences in Groups, 1961) discovered that there are powerful psychological forces inherent in all groups that divert from accomplishing their primary tasks. To overcome these restraining forces and use the potential

  15. Barriers to electric energy efficiency in Ghana

    Science.gov (United States)

    Berko, Joseph Kofi, Jr.

    Development advocates argue that sustainable development strategies are the best means to permanently improve living standards in developing countries. Advocates' arguments are based on the technical, financial, and environmental advantages of sustainable development. However, they have not addressed the organizational and administrative decision-making issues which are key to successful implementation of sustainable development in developing countries. Using the Ghanaian electricity industry as a case study, this dissertation identifies and analyzes organizational structures, administrative mechanisms, and decision-maker viewpoints that critically affect the success of adoption and implementation of energy efficiency within a sustainable development framework. Utilizing semi-structured interviews in field research, decision-makers' perceptions of the pattern of the industry's development, causes of the electricity supply shortfall, and barriers to electricity-use efficiency were identified. Based on the initial findings, the study formulated a set of policy initiatives to establish support for energy use efficiency. In a second set of interviews, these policy suggestions were presented to some of the top decision-makers to elicit their reactions. According to the decision-makers, the electricity supply shortfall is due to rapid urbanization and increased industrial consumption as a result of the structural adjustment program, rural electrification, and the sudden release of suppressed loads. The study found a lack of initiative and collaboration among industry decision-makers, and a related divergence in decision-makers' concerns and viewpoints. Also, lacking are institutional support systems and knowledge of proven energy efficiency strategies and technologies. As a result, planning, and even the range of perceived solutions to choose from are supply-side oriented. The final chapter of the study presents implications of its findings and proposes that any

  16. 7Li breakup polarization potential at near barrier energies

    International Nuclear Information System (INIS)

    Lubian, J. . E-mail lubian@if.uff.br; Correa, T.; Paes, B.; Figueira, J.M.; Abriola, D.; Fernandez Niello, J.O.; Arazi, A.; Capurro, O.A.; de Barbara, E.; Marti, G.V.; Martinez Heinmann, D.; Negri, A.E.; Pacheco, A.J.; Padron, I.; Gomes, P.R.S.

    2007-01-01

    Inelastic and one neutron transfer cross sections at energies around the Coulomb barrier were used to derive dynamic polarization potential (DPP) for the 7 Li + 27 Al system. The DPP due to breakup, obtained in a simple way, indicates that its real part is repulsive at near barrier energies

  17. Barriers and possibilities for low-carbon-energy consuming technologies

    DEFF Research Database (Denmark)

    Bjarklev, Araceli

    consensus that one of the solutions to the current environmental challenge will be based on low-carbon-technologies, there are many issues that set a barrier for its adequate development and still many actors in these sectors are sceptical about the possibilities. Illumination is a very interesting sector...... to target, since it uses 19% of the total electricity produced in the world. Consequently, this paper takes the Danish office lighting sector as a study object and discusses the question: What are the main barriers and possibilities for the energy saving illumination technologies to efficiently reduce...... their ecological footprint. The discussion is supported by using relevant elements of the cradle-to-grave, eco-design and environmental-innovation theories. It is based on active participation in interdisciplinary projects and face-to-face in-depth interviews with relevant actors along the entire Danish...

  18. Barriers to Industrial Energy Efficiency - Study (Appendix A), June 2015

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-06-01

    This study examines barriers that impede the adoption of energy efficient technologies and practices in the industrial sector, and identifies successful examples and opportunities to overcome these barriers. Three groups of energy efficiency technologies and measures were examined: industrial end-use energy efficiency, industrial demand response, and industrial combined heat and power. This study also includes the estimated economic benefits from hypothetical Federal energy efficiency matching grants, as directed by the Act.

  19. Barriers to Industrial Energy Efficiency - Report to Congress, June 2015

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-06-01

    This report examines barriers that impede the adoption of energy efficient technologies and practices in the industrial sector, and identifies successful examples and opportunities to overcome these barriers. Three groups of energy efficiency technologies and measures were examined: industrial end-use energy efficiency, industrial demand response, and industrial combined heat and power. This report also includes the estimated economic benefits from hypothetical Federal energy efficiency matching grants, as directed by the Act.

  20. Nontechnical Barriers to Solar Energy Use: Review of Recent Literature

    Energy Technology Data Exchange (ETDEWEB)

    Margolis, R.; Zuboy, J.

    2006-09-01

    This paper reviews the nontechnical barriers to solar energy use, drawing on recent literature to help identify key barriers that must be addressed as part of the Technology Acceptance efforts under the U.S. Department of Energy (DOE) Solar America Initiative. A broad literature search yielded more than 400 references, which were narrowed to 19 recent documents on nontechnical barriers to the use of solar energy and other energy efficiency and renewable energy (EE/RE) technologies. Some of the most frequently identified barriers included lack of government policy supporting EE/RE, lack of information dissemination and consumer awareness about energy and EE/RE, high cost of solar and other EE/RE technologies compared with conventional energy, and inadequate financing options for EE/RE projects.

  1. BARRIERS TO PHYSICAL ACTIVITY IN THE ELDERLY

    Directory of Open Access Journals (Sweden)

    Paulo Matias

    2015-04-01

    Full Text Available The population awareness of the physical exercise’s benefits is widely diffused. These benefits are particularly important in the elderly because, with increasing age, there is a decline of the musculoskeletal system and the maximum oxygen consumption which reduces the functional fitness of the elderly and can often lead to a significant decline in the quality of life. Despite this awareness, a large part of the population remains sedentary. It is important to know what the barriers are, so they can be circumvented in order to increase the engagement of the elderly population in existing physical activity programs.Objectives: This study aims to identify some of the personal, behavioral and environmental barriers that prevent older adults to be physically active.

  2. Active commuting: prevalence, barriers, and associated variables.

    Science.gov (United States)

    Silva, Kelly Samara; Vasques, Daniel Giordani; Martins, Caroline de Oliveira; Williams, Laura Ashley; Lopes, Adair S

    2011-08-01

    Research has demonstrated that adolescents who actively commute have higher levels of physical activity (PA), which have declined precipitously over the past 30 years. The purpose of this study was to describe the prevalence of active commuting to school; and to identify barriers associated with active commuting. A cross-sectional study was conducted with 1672 students (46.8% boys and 53.2% girls) from 11 to 17 years of age in Caxias do Sul/RS, Brazil. The students were asked to answer questionnaires about active transport, PA, and sedentary behaviors. They also completed a cardiovascular fitness test and body composition measurements. The study used a multivariate Poisson regression analysis. A total of 62.5% of students were observed to actively commute and the prevalence ratio (PR) of not actively commuting was associated with the type of school (Private: 2.41; 1.47, 3.95) and the time spent on commuting (>20 min: 1.93; 1.23, 3.03). The associated barriers to passive commuting were distance (3.02; 1.95, 4.71), crime/danger (2.65; 1.82, 3.85), and traffic (1.75; 1.19, 2.58). This study showed that environmental variables were strongly associated with active commuting. However, no alterations in body composition or other behavioral variables were observed after adjustment.

  3. Urban sound energy reduction by means of sound barriers

    Directory of Open Access Journals (Sweden)

    Iordache Vlad

    2018-01-01

    Full Text Available In urban environment, various heating ventilation and air conditioning appliances designed to maintain indoor comfort become urban acoustic pollution vectors due to the sound energy produced by these equipment. The acoustic barriers are the recommended method for the sound energy reduction in urban environment. The current sizing method of these acoustic barriers is too difficult and it is not practical for any 3D location of the noisy equipment and reception point. In this study we will develop based on the same method a new simplified tool for acoustic barriers sizing, maintaining the same precision characteristic to the classical method. Abacuses for acoustic barriers sizing are built that can be used for different 3D locations of the source and the reception points, for several frequencies and several acoustic barrier heights. The study case presented in the article represents a confirmation for the rapidity and ease of use of these abacuses in the design of the acoustic barriers.

  4. Urban sound energy reduction by means of sound barriers

    Science.gov (United States)

    Iordache, Vlad; Ionita, Mihai Vlad

    2018-02-01

    In urban environment, various heating ventilation and air conditioning appliances designed to maintain indoor comfort become urban acoustic pollution vectors due to the sound energy produced by these equipment. The acoustic barriers are the recommended method for the sound energy reduction in urban environment. The current sizing method of these acoustic barriers is too difficult and it is not practical for any 3D location of the noisy equipment and reception point. In this study we will develop based on the same method a new simplified tool for acoustic barriers sizing, maintaining the same precision characteristic to the classical method. Abacuses for acoustic barriers sizing are built that can be used for different 3D locations of the source and the reception points, for several frequencies and several acoustic barrier heights. The study case presented in the article represents a confirmation for the rapidity and ease of use of these abacuses in the design of the acoustic barriers.

  5. Barriers to the sustainable development of electrical energy in the industrialized nations

    International Nuclear Information System (INIS)

    Ringel, M.; Leonardi, J.

    2003-01-01

    The liberalization of the electricity market in the industrialized nations may considered as an opportunity to bring about a diversification of the energy sector which could help overcome the economic barriers to a more sustainable development By allowing new companies to boost their market share, in many countries increases have been obtained in the supply of electricity based on renewable energy or energy services offering greater efficiency. It is now possible to reduce the cost of the measures which encourage the sustainable development of the sector, taking account of those barriers which prevent the expansion of ENR, hold back further gains in energy efficiency and block a reduction in demand An active energy policy will make it possible to overcome the difficulties encountered in various countries. This study highlights the main barriers to the sustainable development of electrical energy and outlines which solutions may be envisaged to overcome these barriers. (authors)

  6. Transport of the moving barrier driven by chiral active particles

    Science.gov (United States)

    Liao, Jing-jing; Huang, Xiao-qun; Ai, Bao-quan

    2018-03-01

    Transport of a moving V-shaped barrier exposed to a bath of chiral active particles is investigated in a two-dimensional channel. Due to the chirality of active particles and the transversal asymmetry of the barrier position, active particles can power and steer the directed transport of the barrier in the longitudinal direction. The transport of the barrier is determined by the chirality of active particles. The moving barrier and active particles move in the opposite directions. The average velocity of the barrier is much larger than that of active particles. There exist optimal parameters (the chirality, the self-propulsion speed, the packing fraction, and the channel width) at which the average velocity of the barrier takes its maximal value. In particular, tailoring the geometry of the barrier and the active concentration provides novel strategies to control the transport properties of micro-objects or cargoes in an active medium.

  7. Barriers to renewable energy penetration. A framework for analysis

    DEFF Research Database (Denmark)

    Painuly, Jyoti P.

    2001-01-01

    Renewable energy has the potential to play an important role in providing energy with sustainability to the vast populations in developing countries who as yet have no access to clean energy. Although economically viable fur several applications, renewable energy has not been able to realise its...... potential due to several barriers to its penetration. A framework has been developed in this paper to identify the barriers to renewable energy penetration acid to suggest measures to overcome them. (C) 2001 Elsevier Science Ltd. All rights reserved....

  8. Market and policy barriers to energy storage deployment :

    Energy Technology Data Exchange (ETDEWEB)

    Bhatnagar, Dhruv; Currier, Aileen B.; Hernandez, Jacquelynne; Ma, Ookie; Kirby, Brendan

    2013-09-01

    Electric energy storage technologies have recently been in the spotlight, discussed as essential grid assets that can provide services to increase the reliability and resiliency of the grid, including furthering the integration of variable renewable energy resources. Though they can provide numerous grid services, there are a number of factors that restrict their current deployment. The most significant barrier to deployment is high capital costs, though several recent deployments indicate that capital costs are decreasing and energy storage may be the preferred economic alternative in certain situations. However, a number of other market and regulatory barriers persist, limiting further deployment. These barriers can be categorized into regulatory barriers, market (economic) barriers, utility and developer business model barriers, crosscutting barriers and technology barriers. This report, through interviews with stakeholders and review of regulatory filings in four regions roughly representative of the United States, identifies the key barriers restricting further energy storage development in the country. The report also includes a discussion of possible solutions to address these barriers and a review of initiatives around the country at the federal, regional and state levels that are addressing some of these issues. Energy storage could have a key role to play in the future grid, but market and regulatory issues have to be addressed to allow storage resources open market access and compensation for the services they are capable of providing. Progress has been made in this effort, but much remains to be done and will require continued engagement from regulators, policy makers, market operators, utilities, developers and manufacturers.

  9. Barriers' and policies' analysis of China's building energy efficiency

    International Nuclear Information System (INIS)

    Zhang, Yurong; Wang, Yuanfeng

    2013-01-01

    With the rapid economic growth and the improvement of people's living standards, China's building energy consumption has kept rising during the past 15 years. Under the effort of the Chinese government and the society, China's building energy efficiency has made certain achievements. However, the implementation of building energy efficiency in China is still far from its potential. Based on the analysis of the existing policies implemented in China, the article concluded that the most essential and the most effective ways to promote building energy efficiency is the government's involvement as well as economic and financial incentives. In addition, the main barriers in the process of promoting building energy efficiency in China are identified in six aspects. It has been found that the legal system and administrative issues constitute major barriers, and the lack of financial incentives and the mismatching of market mechanism also hamper the promotion of building energy efficiency. Finally, in view of the existing policies and barriers analysis, three corresponding policy proposals are presented. -- Highlights: •The existing policies implemented in China from three aspects are presented and analysed. •The Government's involvement is the most essential effective way to promote building-energy efficiency. •Six aspects of barriers in promoting building energy efficiency in China are identified. •The legal system and administrative issues constitute the major barriers. •Three policy proposals to further promote building energy efficiency in China are proposed

  10. Barriers to increased market-oriented activity

    DEFF Research Database (Denmark)

    Bisp, Søren

    1999-01-01

    and related activities still seem to attract relatively few resources is not answered by supplying another checklist or package of facilitators. Based on published conceptual writings and empirical studies this article makes an account of what the intra-organizational barriers may be to increased market......Most research on market orientation has dealt with assessing how market orientation behaviour is related to business performance. This work has established an intense market-oriented activity as significantly and positively related to business performance under most circumstances. In a maturing......-oriented activity. A framework of six generic domains is suggested: Organizational structure, human resource management, market-oriented activity competence, psychological climate, managers' personality characteristics, and individually held beliefs. A model is suggested inter-relating the domains....

  11. Radiant Barriers Save Energy in Buildings

    Science.gov (United States)

    2014-01-01

    Langley Research Center needed to coat the Echo 1 satellite with a fine mist of vaporized metal, and collaborated with industry to create "radiant barrier technology." In 2010, Ryan Garrett learned about a new version of the technology resistant to oxidation and founded RadiaSource in Ogden, Utah, to provide the NASA-derived technology for applications in homes, warehouses, gymnasiums, and agricultural settings.

  12. Improving energy efficiency in industrial energy systems an interdisciplinary perspective on barriers, energy audits, energy management, policies, and programs

    CERN Document Server

    Thollander, Patrik

    2012-01-01

    Industrial energy efficiency is one of the most important means of reducing the threat of increased global warming. Research however states that despite the existence of numerous technical energy efficiency measures, its deployment is hindered by the existence of various barriers to energy efficiency. The complexity of increasing energy efficiency in manufacturing industry calls for an interdisciplinary approach to the issue. Improving energy efficiency in industrial energy systems applies an interdisciplinary perspective in examining energy efficiency in industrial energy systems, and discuss

  13. Barriers to Physical Activity in Individuals with Spinal Cord Injury

    DEFF Research Database (Denmark)

    Roberton, Terri; Bucks, Romola S.; Skinner, Timothy C.

    2011-01-01

    This study examined barriers to physical activity reported individuals with spinal cord injury (SCI) and the degree to which these barriers differed across varying degrees of independence. Participants were 65 individuals recruited from the Western Australian Spinal Cord Injury database. Data...... on physical activity participation and perceived barriers to physical activity participation were collected using a cross-sectional survey and analysed using independent samples t-tests. We found that, regardless of level of ambulation or ability to transfer, few participants reported being physically active....... While there were no significant differences in the amount of barriers reported by individuals with different levels of independence, the type of barriers reported varied across groups....

  14. Li breakup polarization potential at near barrier energies

    International Nuclear Information System (INIS)

    Lubian, F. J.; Correa, T.; Gomes, P.R.S.; Paes, B; Figueira, J. M.; Abriola, D.; Fernandez, J. O.; Capurro, O. A.; Marti, G.V.; Martinez, D.; Heimann; Negri, A.; Pacheco, A. J.; Padron, I.

    2007-01-01

    Inelastic and one neutron transfer cross sections at energies around the Coulomb barrier were used to derive dynamic polarization potential (DPP) for the 7 Li + 27 Al system. The DPP due to breakup, obtained in a simple way, indicates that its real part is repulsive at nearbarrier energies. (Author)

  15. Renewable Energy Permitting Barriers in Hawaii: Experience from the Field

    Energy Technology Data Exchange (ETDEWEB)

    Busche, S.; Donnelly, C.; Atkins, D.; Fields, R.; Black, C.

    2013-03-01

    This white paper presents a summary of the solicited input from permitting agencies and renewable energy developers on the permitting process in Hawaii to provide stakeholders in Hawaii, particularly those involved in permitting, with information on current permitting barriers that renewable energy developers are experiencing.

  16. Potential and barrier study. Energy efficiency of Norwegian homes; Potensial- og barrierestudie. Energieffektivisering av norske boliger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Enova has identified potentials and barriers for energy efficiency in Norwegian buildings. This report summarizes the results of this work. Efficient energy in buildings is important to ensure that future economic activity and growth can occur in a way that reduces the possibilities for an environmentally and economically sound development. (eb)

  17. Renewable energy resources barriers in Africa

    International Nuclear Information System (INIS)

    Umoh, U.T.; Ekpoh, I.J.

    2008-01-01

    Africa's hydroelectric power plants are not able to perform at greater than 30 per cent of their installed capacity, despite the fact that Africa has abundant hydroelectric resources. Droughts and floods attributed to climate change are presenting challenges to the effective management and distribution of hydroelectric power supplies. This paper identified climate change-related barriers against hydroelectric power development in Africa. Case studies of 3 hydroelectric power projects in Nigeria were considered. Rainfall intensity data for a 25-year period were analyzed. The study showed that while the hydroelectric power plants are capable of supplying more power, most dams in Africa are prone to erosion and flash flooding. The sedimentation of reservoirs and natural lakes are also posing significant water management problems. Redesigns are needed in order to reduce risk. The new hydroelectric projects should be designed to ensure that environmental impacts are minimized. A river basin management approach was recommended in order to improve industrial water supplies, power generation, and recreational aspects of waterways. 11 refs., 2 tabs.

  18. Addressing and overcoming barriers for energy savings in business

    DEFF Research Database (Denmark)

    Dirckinck-Holmfeld, Kasper

    Energy savings are generally viewed as an effective way to cut GHG emissions, as there are huge potentials for improvements because of several barriers and constraining factors for implementing otherwise profitable solutions. Several different polity tools have been applied to overcome these barr......Energy savings are generally viewed as an effective way to cut GHG emissions, as there are huge potentials for improvements because of several barriers and constraining factors for implementing otherwise profitable solutions. Several different polity tools have been applied to overcome...

  19. Identifying barriers in the diffusion of renewable energy sources

    International Nuclear Information System (INIS)

    Eleftheriadis, Iordanis M.; Anagnostopoulou, Evgenia G.

    2015-01-01

    Rapid diffusion of renewable energy sources (RES) in the electricity power sector is crucial if the EU wants to fulfill its 2050 CO 2 reduction commitments. For this reason, identifying and alleviating all barriers that hinder the development of RES is necessary to the successful deployment of these technologies. This paper discusses the main barriers in the diffusion of wind and photovoltaic (PV) solar power in the Greek electricity sector by drawing on the literature of technological innovation systems and system functions. Furthermore, we provide an explanation of the different diffusion rates between the two technologies. Inadequate financial resources, low grid capacity, delays in the issuance of building permits, opposition from local communities to the construction of wind farms and the lack of a stable institutional framework are among the most important barriers that inhibit the diffusion of the wind and PV solar power. The nature of the barriers identified in this study calls for policy intervention. - Highlights: • Firms in the Greek wind and solar power sectors assess RES barriers. • Lack of financial resources is the most important RES barrier. • Lack of a stable institutional framework negatively affects RES deployment. • The support of the public sector is crucial to the diffusion of RES. •Wind power faces strong legitimization barriers

  20. Efficient free energy calculations for compounds with multiple stable conformations separated by high energy barriers

    NARCIS (Netherlands)

    Hritz, J.; Oostenbrink, C.

    2009-01-01

    Compounds with high intramolecular energy barriers represent challenging targets for free energy calculations because of the difficulty to obtain sufficient conformational sampling. Existing approaches are therefore computationally very demanding, thus preventing practical applications for such

  1. Renewable energy: Externality costs as market barriers

    International Nuclear Information System (INIS)

    Owen, Anthony D.

    2006-01-01

    This paper addresses the impact of environmentally based market failure constraints on the adoption of renewable energy technologies through the quantification in financial terms of the externalities of electric power generation, for a range of alternative commercial and almost-commercial technologies. It is shown that estimates of damage costs resulting from combustion of fossil fuels, if internalised into the price of the resulting output of electricity, could lead to a number of renewable technologies being financially competitive with generation from coal plants. However, combined cycle natural gas technology would have a significant financial advantage over both coal and renewables under current technology options and market conditions. On the basis of cost projections made under the assumption of mature technologies and the existence of economies of scale, renewable technologies would possess a significant social cost advantage if the externalities of power production were to be 'internalised'. Incorporating environmental externalities explicitly into the electricity tariff today would serve to hasten this transition process. (author)

  2. [Prevalence of barriers for physical activity in adolescents].

    Science.gov (United States)

    Santos, Mariana Silva; Hino, Adriano Akira Ferreira; Reis, Rodrigo Siqueira; Rodriguez-Añez, Ciro Romélio

    2010-03-01

    The aim of this study was to analyze the prevalence and association of barriers to physical activity among adolescents. This cross-sectional study evaluated a representative sample of public high school students in Curitiba-PR, Brazil. A total of 1,609 school adolescents (59.7% male) between 14 and 18 years of age answered a questionnaire on physical activity status and barriers to physical activity. Logistic regressions were conducted for each barrier investigated to verify the association between the prevalence of barriers and physical activity, adjusting for confounding variables (age and socioeconomic status). Analyses were done separately for boys and girls. Only 22% of boys and 9% of girls achieved the current physical activity recommendation. Among the 12 barriers investigated, only "there is nobody to take" did not differ between boys and girls. The perception of barriers was higher for girls than boys (p barriers. "Lack of friends company" and "feel lazy" were the barriers most often reported by boys (30.4%) and girls (51.8%) respectively; however, the barrier most strongly associated with prevalence of physical inactivity was "prefer to do other things" for both boys (OR = 5.02 (2.69 - 9.37); p barriers for the practice of physical activity were more prevalent in girls and differed as to the extent of importance between genders.

  3. Promoting Physical Activity: Addressing Barriers and Moving Forward

    Science.gov (United States)

    Beighle, Aaron; Morrow, James R.

    2014-01-01

    The barriers that keep individuals from adopting and maintaining active lifestyles are very complex. Strategies for overcoming these barriers and to incentivize and assist inactive individuals to benefit from physical activity are necessary. In addition, it is important to examine the impact of public policy on active living. As youth physical…

  4. Renewable energy market conditions and barriers in Turkey

    International Nuclear Information System (INIS)

    Nalan, Cicek Bezir; Murat, Oeztuerk; Nuri, Oezek

    2009-01-01

    Decentralized wind, hydropower, biogas and biomass, geothermal, solar thermal and solar electricity energy systems are the most commonly found renewable energy technologies promoted for rural energy supply within sustainable developments programs. They are, therefore, seen to have a central place in the practice of sustainable development and in allowing less development countries to bypass the environmentally damaging fossil fuel intensive paths made by industrialized countries. On the political front, many less development countries are critical of pressure on them to adopt environmental energy technologies. Turkey is situated the meeting point of three continents (Asia, Europe and Africa) and stands as a bridge between Asia and Europe. The country is located in southeastern Europe and southwestern Asia. As Turkey's economy has expanded in recent years, the consumption of primary energy has increased. Presently in order to increase the energy production from domestic energy resources, decrease the use of fossil fuels as well as reduce of green house gas emissions different renewable energy sources are used for energy production in Turkey. The share of energy production from renewable energy sources has increased during the last 10 years. Turkey must import most of the energy to meet her needs. Turkey also has a large potential for renewable energies. The lack of knowledge about renewable energy technologies by most policy-makers, potential consumers, and energy firm managers has played against renewable energy developments. The paper presents renewable energy used in Turkey and Europe Union and evaluation of the market conditions and barriers of renewable energy use in Turkey. (author)

  5. Reducing barriers to energy efficiency in the German energy service companies sector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Koewener, D.; Schleich, J.

    2000-12-01

    This report describes the empirical research conducted in the German energy service sector to assess to what extent energy service companies (ESCOs) can help overcome the barriers to energy in the higher education, brewing and mechanical engineering sectors. This report complements the sector for Germany within the BARRIERS project (Sorrell et al., 2000; Schleich/Boede 2000a; Schleich/Boede 2000b; Schleich et al., 2000). The report characterises the German energy service sector, contains a description and analysis of four case studies in the energy service sector, identifies the main barriers and chances for ESCOs in the higher education, brewery and mechanical engineering sectors, and concludes with brief recommendations on how these barriers may be overcome. The results of the study are summarised here under the following headings: Characterising the energy service sector in Germany; - Case studies of energy service companies in Germany; - The role of ESCOs in the case-study sectors; - Policy implications. (orig.)

  6. Energy Barriers and Hysteresis in Martensitic Phase Transformations

    Science.gov (United States)

    2008-08-01

    glacial acetic acid (CH3COOH) and 10-15% perchloric acid (HCLO4) by volume, the cathode was stainless steel , the anode was stainless steel or Ti, the...Submitted to Acta Materialia Energy barriers and hysteresis in martensitic phase transformations Zhiyong Zhang, Richard D. James and Stefan Müller...hysteresis based on the growth from a small scale of fully developed austenite martensite needles. In this theory the energy of the transition layer plays a

  7. Energy management action plan: Developing a strategy for overcoming institutional barriers to municipal energy conservation

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    Energy offices working to improve efficiency of local government facilities face not only technical tasks, but institutional barriers, such as budget structures that do not reward efficiency, a low awareness of energy issues, and purchasing procedures based only on minimizing initial cost. The bureau, in working to remove such barriers in San Francisco, has identified 37 institutional barriers in areas such as operations & maintenance, purchasing, and facility design; these barriers were then reorganized into three groupings-- policy & attitudes, budget & incentives, and awareness & information-- and mapped. This map shows that the barriers mutually reinforce each other, and that a holistic approach is required for permanent change. The city`s recreation & parks department was used as a model department, and information about facility energy use was compiled into a departmental energy review. Staff interviews showed how barriers affect conservation. The bureau then generated ideas for projects to remove specific barriers and rated them according to potential impact and the resources required to implement them. Four of the six projects selected focused on maintenance staff: a cost- sharing lighting retrofit program, a boiler efficiency program, a departmental energy tracking system, and a budgetary incentive program for conservation. The other two projects are city-wide: promotion of a new term contract supplying energy-efficient light materials, and publication/distribution of ENERGY NEWS newsletter. A general methodology, the EMAP Strategy Guide, has been created to assist other energy offices in developing EMAPs.

  8. A path method for finding energy barriers and minimum energy paths in complex micromagnetic systems

    International Nuclear Information System (INIS)

    Dittrich, R.; Schrefl, T.; Suess, D.; Scholz, W.; Forster, H.; Fidler, J.

    2002-01-01

    Minimum energy paths and energy barriers are calculated for complex micromagnetic systems. The method is based on the nudged elastic band method and uses finite-element techniques to represent granular structures. The method was found to be robust and fast for both simple test problems as well as for large systems such as patterned granular media. The method is used to estimate the energy barriers in CoCr-based perpendicular recording media

  9. Hydration effects on the photoionization energy of 2‧-deoxyguanosine 5‧-phosphate and activation barriers for guanine methylation by carcinogenic methane diazonium ions

    Science.gov (United States)

    Eichler, Daniel R.; Hamann, Haley A.; Harte, Katherine A.; Papadantonakis, George A.

    2017-07-01

    Results from DFT calculations indicate that states originating from gas-phase ionization of the phosphate and the base are degenerate in syn-5‧-dGMP- and that bulk hydration lowers the base-localized ionization energy by diazonium ions are lower at the N7 than at the O6 sites and they are influenced by local ionization energy and steric interference.

  10. Sustainability and energy self-sufficiency; overcoming the barriers

    Directory of Open Access Journals (Sweden)

    Rania Abdel Galil

    2015-12-01

    Full Text Available Engendering more positive attitudes to renewable energy is by no means a simple feat. Renewable energy technologies are viewed as radical innovations which necessitate substantial changes in production and consumption patterns, hence often met with resistance from both institutions and individuals. Yet action is needed; global energy consumption is expected to rise by 41% and global carbon dioxide emissions by 29%, with most of the demand and rise coming from emerging economies (BP energy outlook 2035. Further, countries need to meet objectives of reduction of GHG under the United Nations Framework Convention on Climate Change. Renewable energy share in the global energy mix needs to significantly increase in order to reach supply sufficiency, energy security, energy equity and environmental sustainability.Meeting demands of energy is critical for the economic and social development of any country; energy must be secure, accessible and affordable at all levels of society, and any negative impact of energy production and energy use on the environment must be minimized. Middle East energy consumption is expected to grow by 69% whilst production to grow by 32%, with 97% of demand still met by fossil fuels by the end of the 2035. Energy investment of $316 billion will be required in the Middle East and North Africa (MENA between 2015 and 2019 to meet its growing demand for power (Apicorp, 2014. Diversifying energy sources is indeed of interest in the MENA region, spurred by growing demand for power and desalinated water, fluctuating fuel price, GHG emission reduction targets, depleting fossil fuel reserves and advances in renewable energy technology. However, there are many barriers that hinder the adoption of renewable energy technologies worldwide, but more so in the MENA region. These barriers are political, economic, social and technological. With a focus on Europe and MENA, it can be said that these barriers have much in common albeit framing

  11. Developing effective rockfall protection barriers for low energy impacts

    Science.gov (United States)

    Mentani, Alessio; Giacomini, Anna; Buzzi, Olivier; Govoni, Laura; Gottardi, Guido; Fityus, Stephen

    2016-04-01

    Recently, important progresses have been made towards the development of high capacity rockfall barriers (100 kJ - 8000 kJ). The interest of researchers and practitioners is now turning to the development of fences of minor capacity, whose use becomes essential in areas where rockfall events generally have low intensity and the use of high capacity barriers would be accompanied by excessive costs and high environmental impact. Low energy barriers can also provide a cost-effective solution even in areas where high energies events are expected. Results of full-scale tests are vital to any investigation on the behaviour of these structures. An experimental set-up has been developed at The University of Newcastle (AUS), to investigate the response of low energy rockfall barrier prototypes to low energy impacts. The Australian territory, and in particular New South Wales, is in fact characterised by rockfall events of low-to-medium intensity (50 kJ - 500 kJ) and the need of protection structures working within such energy range, is particularly felt [1]. The experiments involved the impact of a test block onto three spans, low energy barrier prototypes, made of steel structural posts, fully fixed at the base, side cables and a steel meshwork constituted by a double twist hexagonal wire net [2]. Test data enabled the development, calibration and assessment of FE models [3], on which non-linear and dynamic analyses have been performed addressing the effect of the block size. Results have shown that the response of the structure is strongly governed by the net. Data from tests conducted on the sole net and on the entire barrier showed in fact a similar trend, different to what typically observed for high capacity barriers, whose behaviour is also led by the presence of uphill cables and brakes. In particular, the numerical analyses have demonstrated a dependence of the net performance on the block size. In particular, a loss of capacity in the order of 50% occurred as the

  12. Identifying barriers to aboriginal renewable energy deployment in Canada

    International Nuclear Information System (INIS)

    Krupa, Joel

    2012-01-01

    As one of the largest and wealthiest countries in the world, Canada stands well-positioned to take advantage of ongoing growth in North American demand for primary energy supply by expanding domestic delivery of renewable energy generation to internationally interconnected electric grids across the country. There are myriad benefits of adopting the renewable energy approach to development—as the province of Ontario has acknowledged through the implementation of their 2009 Green Energy Act—including drastic reductions in carbon emissions, the decommissioning of existing fossil fuel power generation that cause serious public health problems, and opportunities for sustainable development at the community level. One group in particular stands poised to shape these debates. In Canada, historically marginalized Aboriginal peoples remain one of the groups with the greatest potential for meeting these enormous renewable energy deployment needs. Aboriginal involvement in renewable energy generation in Canada has been as diverse as Canada's Aboriginal peoples and groups have already adopted a range of different solutions to meet energy supply needs. However, many significant barriers exist that prevent this diverse cultural group from reaching its full potential. The article identifies some of these shortcomings and analyzes their roots. - Highlights: ► Renewable energy is one of the most important sustainable development opportunities today. ► Aboriginal-led renewable development could dramatically increase Canadian supply. ► Surmountable barriers are identified.

  13. Direct measurement of free-energy barrier to nucleation of crystallites in amorphous silicon thin films

    Science.gov (United States)

    Shi, Frank G.

    1994-01-01

    A method is introduced to measure the free-energy barrier W(sup *), the activation energy, and activation entropy to nucleation of crystallites in amorphous solids, independent of the energy barrier to growth. The method allows one to determine the temperature dependence of W(sup *), and the effect of the preparation conditions of the initial amorphous phase, the dopants, and the crystallization methds on W(sup *). The method is applied to determine the free-energy barrier to nucleation of crystallites in amorphous silicon (a-Si) thin films. For thermally induced nucleation in a-Si thin films with annealing temperatures in the range of from 824 to 983 K, the free-energy barrier W(sup *) to nucleation of silicon crystals is about 2.0 - 2.1 eV regardless of the preparation conditions of the films. The observation supports the idea that a-Si transforms into an intermediate amorphous state through the structural relaxation prior to the onset of nucleation of crystallites in a-Si. The observation also indicates that the activation entropy may be an insignificant part of the free-energy barrier for the nucleation of crystallites in a-Si. Compared with the free-energy barrier to nucleation of crystallites in undoped a-Si films, a significant reduction is observed in the free-energy barrier to nucleation in Cu-doped a-Si films. For a-Si under irradiation of Xe(2+) at 10(exp 5) eV, the free-energy barrier to ion-induced nucleation of crystallites is shown to be about half of the value associated with thermal-induced nucleation of crystallites in a-Si under the otherwise same conditions, which is much more significant than previously expected. The present method has a general kinetic basis; it thus should be equally applicable to nucleation of crystallites in any amorphous elemental semiconductors and semiconductor alloys, metallic and polymeric glasses, and to nucleation of crystallites in melts and solutions.

  14. Free energy barriers to evaporation of water in hydrophobic confinement.

    Science.gov (United States)

    Sharma, Sumit; Debenedetti, Pablo G

    2012-11-08

    We use umbrella sampling Monte Carlo and forward and reverse forward flux sampling (FFS) simulation techniques to compute the free energy barriers to evaporation of water confined between two hydrophobic surfaces separated by nanoscopic gaps, as a function of the gap width, at 1 bar and 298 K. The evaporation mechanism for small (1 × 1 nm(2)) surfaces is found to be fundamentally different from that for large (3 × 3 nm(2)) surfaces. In the latter case, the evaporation proceeds via the formation of a gap-spanning tubular cavity. The 1 × 1 nm(2) surfaces, in contrast, are too small to accommodate a stable vapor cavity. Accordingly, the associated free energy barriers correspond to the formation of a critical-sized cavity for sufficiently large confining surfaces, and to complete emptying of the gap region for small confining surfaces. The free energy barriers to evaporation were found to be of O(20kT) for 14 Å gaps, and to increase by approximately ~5kT with every 1 Å increase in the gap width. The entropy contribution to the free energy of evaporation was found to be independent of the gap width.

  15. Barriers to outdoor physical activity in wintertime among Somali youth.

    Science.gov (United States)

    Rothe, Elizabeth; Holt, Christina; Kuhn, Celine; McAteer, Timothy; Askari, Isabella; O'Meara, Mary; Sharif, Abdimajid; Dexter, William

    2010-10-01

    To identify barriers to outdoor physical activity in winter among Somali youth in Maine. Despite the many proven health benefits of physical activity among children, such as cardiovascular fitness and health status as an adult, there has been a decrease in physical activity among children in recent years. Specifically, children who are of low socio-economic status or are from communities where many immigrants are at increased risk for developing obesity. Immigrants are also less likely to be physically active. There are many potential barriers to wintertime physical activity among Somali youth in Maine, such as lack of financial resources, transportation, proper winter clothing, and appropriate knowledge of winter safety, and language and cultural barriers. For females, different attire required for outdoor activity may be a barrier. Somali parents and children were recruited from Portland, Maine to participate in focus groups led by a trained facilitator with a Somali translator and cultural broker. Transcripts were coded using NVIVO software to identify barriers to physical activity among Somali youth outside in winter. Eight focus groups were conducted. Sixty-one Somali community members were recruited. Participants felt outdoor physical activity is important, but note that it is decreased in winter. Barriers to outdoor activity in winter cited by focus group participants were lack of resources, health concerns, gender barriers for females, and knowledge barriers. Concern over lack of supervision while children play outside was also cited. This study revealed many of the underlying beliefs, barriers and cultural issues that impact Somali families' intention to be active and ability to be active outdoors in winter. These findings can be used to generate research hypotheses and public health interventions regarding outdoor physical activity among Somali youth.

  16. Analysis of Relationships among Organizational Barriers to Energy Efficiency Improvement: A Case Study in Indonesia’s Steel Industry

    Directory of Open Access Journals (Sweden)

    Apriani Soepardi

    2018-01-01

    Full Text Available The aim of this paper is to analyze and rank the managerial-organizational barriers to energy efficiency improvement from an industry perspective. To that end, this study utilizes the Interpretive Structural Modeling (ISM methodology to identify the contextual relationships among the barriers. In a focus group discussion forum, five practitioners from the steel industry were consulted to identify these mutual linkages. The results indicated that five of the eight barriers proposed are in the linkage category. These barriers include that the energy manager or people in charge of energy management lack influence, there are higher priorities to production activity, there is management resistance to change, there is inadequate management capacity, and there are conflicts of interest within the organization. The management should focus more attention on these barriers, because they have both high driving power and dependency. The findings are intended to help managers from manufacturing sectors identify key barriers and thus develop strategic plans to address these issues.

  17. Transition to distributed energy generation in Finland: Prospects and barriers

    International Nuclear Information System (INIS)

    Ruggiero, Salvatore; Varho, Vilja; Rikkonen, Pasi

    2015-01-01

    Small-scale distributed energy generation is expected to play an important role in helping Finland increase its energy self-sufficiency. However, the overall strategy to date for promoting distributed energy remains unclear. It is not yet well understood which factors promote the growth of the distributed energy sector and what barriers need to be removed. In this article we present the results of a questionnaire directed at a panel of 26 experts from the distributed energy value chain and 15 semi-structured interviews with industry and non-industry representatives. We investigated, from a sociotechnical transition perspective, the possibilities and challenges of the transition to distributed energy in Finland through 2025. The results show that a shift to a prosperous future for distributed energy is possible if permit procedures, ease of grid connection, and taxation laws are improved in the electricity sector and new business concepts are introduced in the heat sector. In contrast to other European countries, the transition in Finland is expected to take place through a market-based approach favoring investment-focused measures. We conclude that incentive-based schemes alone, whatever they may be, will be insufficient to create significant growth in Finland without institutional change, removal of barriers, and the engagement of key actors. - Highlights: • We examine the possibilities and challenges of the transition to DE in Finland. • Technological niches are emerging both in the heat and electricity sector. • Business model innovation is evident only in the electricity sector. • Removing barriers and developing new business models will accelerate the transition.

  18. Linear and non-linear energy barriers in systems of interacting single-domain ferromagnetic particles

    International Nuclear Information System (INIS)

    Petrila, Iulian; Bodale, Ilie; Rotarescu, Cristian; Stancu, Alexandru

    2011-01-01

    A comparative analysis between linear and non-linear energy barriers used for modeling statistical thermally-excited ferromagnetic systems is presented. The linear energy barrier is obtained by new symmetry considerations about the anisotropy energy and the link with the non-linear energy barrier is also presented. For a relevant analysis we compare the effects of linear and non-linear energy barriers implemented in two different models: Preisach-Neel and Ising-Metropolis. The differences between energy barriers which are reflected in different coercive field dependence of the temperature are also presented. -- Highlights: → The linear energy barrier is obtained from symmetry considerations. → The linear and non-linear energy barriers are calibrated and implemented in Preisach-Neel and Ising-Metropolis models. → The temperature and time effects of the linear and non-linear energy barriers are analyzed.

  19. Barriers to the use of renewable energy in Western Australia

    International Nuclear Information System (INIS)

    Harman, F.; Stocker, L.; Walker, I.; Stirling, M.

    1991-08-01

    Public attitudes towards renewable energy sources, in particular solar energy is examined through a survey of water heating in the metropolitan area, energy supply and use on pastoral leases in Western Australia. The private costs of water heating systems was assessed in a way which may give guidance to manufacturers on improving the economics of solar water heating systems, and to policy makers for facilitating the use of solar water heating systems. The policies currently in place in Western Australia which act as barriers to the greater use of renewable energy were also outlined. The cost data, together with the attitudes of consumers as revealed in the surveys, indicate that manufacturers and suppliers of renewable energy equipment need to reduce costs and improve the actual and perceived capability, performance and reliability of their equipment. 96 refs., 30 tabs., 38 figs

  20. Heavy ion collisions at energies near the Coulomb barrier 1990

    International Nuclear Information System (INIS)

    Nagarajan, M.A.

    1991-01-01

    During recent years, detailed experimental and theoretical investigations have been carried out on heavy ion collisions at energies close to the Coulomb barrier. These studies have provided direct evidence of strong couplings between the various reaction channels available at energies near the top of the Coulomb barrier. This field of research has remained the focus of interest and with improved experimental techniques, new detailed high resolution data have been obtained. The workshop on ''Heavy Ion Collisions at Energies Close to the Coulomb Barrier'' was organized with the aim of reviewing the current understanding of the collision dynamics and to discuss future directions in this area of research. The topics discussed at the workshop were broadly classified under the titles: quasielastic reactions; fusion of heavy ions; and shape and spin dependence in heavy ion collisions. The last of these topics was included to review new data obtained with polarized heavy ions and their theoretical interpretations. This volume contains the invited and contributed talks as well as a few short presentations during panel discussions. (author)

  1. Investigating the status and barriers of science laboratory activities ...

    African Journals Online (AJOL)

    This study aims at investigating the barriers encountered by science teachers in laboratory activities in Rwandan teacher training colleges (TTCs) using questionnaires and interviews. The results confirmed that teachers face barriers like time limitation, material scarcity and lack of improvising skills in their everyday science ...

  2. Pair transfer processes probed at deep sub barrier energies

    International Nuclear Information System (INIS)

    Corradi, L.; Mason, P.; Fioretto, E.; Michelagnoli, C.; Stefanini, A.M.; Valiente-Dobon, J.J.; Szinler, S.; Jelavic-Malenica, D.; Soic, N.; Pollarolo, G.; Farnea, E.; Montagnoli, G.; Montanari, D.; Scarlassara, F.; Ur, C.A.; Gadea, A.; Haas, F.; Marginean, N.

    2011-01-01

    Multinucleon transfer cross sections in the system 40 Ca+ 96 Zr have been measured at bombarding energies ranging from the Coulomb barrier to ∼ 25% below. Target-like (lighter) recoils in inverse kinematics have been completely identified in A,Z and Q-value with the large solid angle magnetic spectrometer PRISMA. The experimental slopes of the neutron transfer probabilities at large internuclear separation are consistent with the values derived from the binding energies. A phenomenological interpretation of the transfer probabilities indicates the presence of enhanced values for the even number of neutron transfers. (authors)

  3. Deformation energy of a toroidal nucleus and plane fragmentation barriers

    International Nuclear Information System (INIS)

    Fauchard, C.; Royer, G.

    1996-01-01

    The path leading to pumpkin-like configurations and toroidal shapes is investigated using a one-parameter shape sequence. The deformation energy is determined within the analytical expressions obtained for the various shape-dependent functions and the generalized rotating liquid drop model taking into account the proximity energy and the temperature. With increasing mass and angular momentum, a potential well appears in the toroidal shape path. For the heaviest systems, the pocket is large and locally favourable with respect to the plane fragmentation barriers which might allow the formation of evanescent toroidal systems which would rapidly decay in several fragments to minimize the surface tension. (orig.)

  4. Energy Transition and Barriers on the Path to its Introduction

    Directory of Open Access Journals (Sweden)

    Tomislav Tkalec

    2015-12-01

    Full Text Available Energy transition is a concept originating from the necessity of solving environmental problems and conflicts in the energy sector. It originates from environmental tradition and advocates transition from environmentally and socially controversial sources of energy to renewables. That also means a shift from large centralized production units (mainly based on fossil and nuclear energy to smaller, dispersed ones. This decentralization process inherently leads to a democratization of the electricity sector, as large energy companies are losing their power and position in the energy policy arena, as more and more smaller actors emerge. However, when trying to change the electricity system, many obstacles arise – from the economics, old energy paradigm, path dependence, inertia of electricity system, power relations between actors, institutional lock-in, to perceptions and values of the dominant players. All barriers are reflected in the energy policy arena, dominated mainly by large energy companies, reluctant to accept changes. Demands for a change come from non-dominant actors, mainly from civil society actors and others, who are pushed to the margins of the political arena. Therefore, decision-makers should recognize their role, change institutional structure of the energy policy arena, and open it to various actors that can add new qualities to decision-making processes and outputs.

  5. Perceived barriers to physical activity among Nigerian stroke survivors.

    Science.gov (United States)

    Idowu, Opeyemi Ayodiipo; Adeniyi, Ade Fatai; Ogwumike, Omoyemi Olubunmi; Fawole, Henrietta Oluwafunmilola; Akinrolie, Olayinka

    2015-01-01

    Benefits of physical activity in the prevention and management of stroke are well documented in the literature. There is increasing evidence that stroke survivors in South-West Nigeria are physically inactive. Data on barriers to the achievement of the recommended physical activity levels including its differences along socio-demographic characteristics among stroke survivors in South-West Nigeria are needed. The Exercise Benefits and Barrier Scale and the International Physical Activity Questionnaire were administered on 121 stroke survivors to determine their perceived barriers to physical activity and physical activity levels respectively. Information on socio-demographic data and clinical variables were also collected. The sample included 70.2% males, with majority of the participants reporting low physical activity levels (80.2%) and high perceived barriers (Mean = 48.13, SD = 7.88). The four most reported common barriers among stroke survivors were access to exercise facilities (95.0%), being embarrassed to exercise (94.2%), economic cost demands of exercise (94.2%) and notion that people in exercise clothes look funny (94.2%) respectively. There were no significant differences found in barriers to physical activity between gender (U = 1471.00, P = 0.74) and across each of: occupational status (H = 4.37, P = 0.22), age group (H = 0.82, P = 0.84) and educational levels (H = 4.56, P = 0.33). Significant difference however existed in perceived barriers across marital status categories (H = 12.87, P = 0.05). Stroke survivors indicated high perceived barriers to physical activity and these barriers were associated with marital status.

  6. Reactions with weakly bound nuclei at near barrier energies

    International Nuclear Information System (INIS)

    Nanal, Vandana

    2014-01-01

    In reactions with weakly bound nuclei, the effect of breakup on fusion process has attracted much attention in recent years. The experimental study shows that breakup channel leads to suppression of complete fusion at above barrier energies due to loss of flux. The fusion barrier distribution can provide a further insight into understanding the influence of coupling to the breakup channels. Similar information could be obtained from the elastic and quasielastic (QEL) scattering because of the conservation of the reaction flux (i.e. R+T= 1), where R is the reflection probability and T is the transmission probability. Thus, quasi-elastic scattering at backward angles is the counterpart of the fusion process and it is expected that the barrier distributions extracted from two processes, namely, QEL and fusion should be similar. While this is true for tightly bound reaction systems, in reactions involving weakly bound projectiles significant differences have been observed for QEL barrier distributions with and without inclusion of breakup processes. This talk will present the recent results for fusion and quasi-elastic scattering in "6","7Li + "1"9"7Au system. Developmental efforts towards a momentum achromatic separator, MARIE, to extract projectile-like secondary ion beams following the reactions of heavy-ion beams from superconducting LINAC booster at Mumbai will also be presented. (author)

  7. Low energy pion detection by a silicon surface barrier telescope

    International Nuclear Information System (INIS)

    Sealock, R.M.; Caplan, H.S.; Leung, M.K.

    1978-01-01

    Four telescopes of three (2-ΔE, 1-E) silicon surface barrier detectors each, mounted in the focal plane of a magnetic spectrometer, have been used to detect positive pions in the energy range from 4.7-17.9 MeV and negative pions from 14.1-17.9 MeV. Positive pions from 4.7-12.7 MeV were stopped in the third detector while positive and negative pions from 14.1-17.9 MeV were detected in transmission. For energies greater than 7.4 MeV aluminum moderators were placed in front of the first detector to degrade the pion energy. Energy spectra show well resolved pion peaks with extremely low background. Double differential cross sections for the 12 C(e,π + ) 12 B,e' reaction have been measured. (Auth.)

  8. Science Activities in Energy: Electrical Energy.

    Science.gov (United States)

    Oak Ridge Associated Universities, TN.

    Presented is a science activities in energy package which includes 16 activities relating to electrical energy. Activities are simple, concrete experiments for fourth, fifth and sixth grades which illustrate principles and problems relating to energy. Each activity is outlined in a single card which is introduced by a question. A teacher's…

  9. Measuring Perceived Barriers to Physical Activity in Adolescents.

    Science.gov (United States)

    Gunnell, Katie E; Brunet, Jennifer; Wing, Erin K; Bélanger, Mathieu

    2015-05-01

    Perceived barriers to moderate-to-vigorous physical activity (PA) may contribute to the low rates of moderate-to-vigorous PA in adolescents. We examined the psychometric properties of scores from the perceived barriers to moderate-to-vigorous PA scale (PB-MVPA) by examining composite reliability and validity evidence based on the internal structure of the PB-MVPA and relations with other variables. This study was a cross-sectional analysis of data collected in 2013 from adolescents (N = 507; Mage = 12.40, SD = .62) via self-report scales. Using exploratory and confirmatory factor analyses, we found that perceived barriers were best represented as two factors representing internal (e.g., "I am not interested in physical activity") and external (e.g., "I need equipment I don't have") dimensions. Composite reliability was over .80. Using multiple regression to examine the relationship between perceived barriers and moderate-to-vigorous PA, we found that perceived internal barriers were inversely related to moderate-to-vigorous PA (β = -.32, p barriers (p > .26). The PB-MVPA scale demonstrated evidence of score reliability and validity. To improve the understanding of the impact of perceived barriers on moderate-to- vigorous PA in adolescents, researchers should examine internal and external barriers separately.

  10. Physical activity barriers and facilitators among working mothers and fathers.

    Science.gov (United States)

    Mailey, Emily L; Huberty, Jennifer; Dinkel, Danae; McAuley, Edward

    2014-06-27

    The transition to parenthood is consistently associated with declines in physical activity. In particular, working parents are at risk for inactivity, but research exploring physical activity barriers and facilitators in this population has been scarce. The purpose of this study was to qualitatively examine perceptions of physical activity among working parents. Working mothers (n = 13) and fathers (n = 12) were recruited to participate in one of four focus group sessions and discuss physical activity barriers and facilitators. Data were analyzed using immersion/crystallization in NVivo 10. Major themes for barriers included family responsibilities, guilt, lack of support, scheduling constraints, and work. Major themes for facilitators included being active with children or during children's activities, being a role model for children, making time/prioritizing, benefits to health and family, and having support available. Several gender differences emerged within each theme, but overall both mothers and fathers reported their priorities had shifted to focus on family after becoming parents, and those who were fitting in physical activity had developed strategies that allowed them to balance their household and occupational responsibilities. The results of this study suggest working mothers and fathers report similar physical activity barriers and facilitators and would benefit from interventions that teach strategies for overcoming barriers and prioritizing physical activity amidst the demands of parenthood. Future interventions might consider targeting mothers and fathers in tandem to create an optimally supportive environment in the home.

  11. 8B + 208Pb Elastic Scattering at Coulomb Barrier Energies

    Science.gov (United States)

    La Commara, M.; Mazzocco, M.; Boiano, A.; Boiano, C.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Signorini, C.; Strano, E.; Torresi, D.; Yamaguchi, H.; Kahl, D.; Di Meo, P.; Grebosz, J.; Imai, N.; Hirayama, Y.; Ishiyama, H.; Iwasa, N.; Jeong, S. C.; Jia, H. M.; Kim, Y. H.; Kimura, S.; Kubono, S.; Lin, C. J.; Miyatake, H.; Mukai, M.; Nakao, T.; Nicoletto, M.; Sakaguchi, Y.; Sánchez-Benítez, A. M.; Soramel, F.; Teranishi, T.; Wakabayashi, Y.; Watanabe, Y. X.; Yang, L.; Yang, Y. Y.

    2018-02-01

    The scattering process of weakly-bound nuclei at Coulomb barrier energies provides deep insights on the reaction dynamics induced by exotic nuclei. Within this framework, we measured for the first time the scattering process of the short-lived Radioactive Ion Beam (RIB) 8B (Sp = 0.1375 MeV) from a 208Pb target at 50 MeV beam energy. The 8B RIB was produced by means of the in-flight facility CRIB (RIKEN, Japan) with an average intensity on target of 10 kHz and a purity about 25%. Elastically scattering ions were detected in the angular range θc.m. = 10°-160° by means of the detector array EXPADES. A preliminary optical model analysis indicates a total reaction cross section of about 1 b, a value, once reduced, 2-3 times larger than those obtained for the reactions induced by the stable weakly-bound projectiles 6,7Li on a 208Pb target in the energy range around the Coulomb barrier.

  12. Barriers to clean development mechanism renewable energy projects in Mexico

    International Nuclear Information System (INIS)

    Lokey, Elizabeth

    2009-01-01

    Mexico is not reaching its full potential to capture benefits from clean development mechanism (CDM) projects because of its limited market for independent power producers (IPPs) and the barriers imposed on these entities by the state-run electric utility that controls most of the country's generation and transmission. This state-run entity has pursued CDM revenues only in isolated cases where international financial assistance was given because it is bound by law to pursue the least-cost generation option for its customers. Recent changes in Mexican legislation that provide incentives for renewable energy development could open the marketplace for these types of projects. (author)

  13. International Collaboration Activities on Engineered Barrier Systems

    Energy Technology Data Exchange (ETDEWEB)

    Jove-Colon, Carlos F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-08-31

    The Used Fuel Disposition Campaign (UFDC) within the DOE Fuel Cycle Technologies (FCT) program has been engaging in international collaborations between repository R&D programs for high-level waste (HLW) disposal to leverage on gathered knowledge and laboratory/field data of near- and far-field processes from experiments at underground research laboratories (URL). Heater test experiments at URLs provide a unique opportunity to mimetically study the thermal effects of heat-generating nuclear waste in subsurface repository environments. Various configurations of these experiments have been carried out at various URLs according to the disposal design concepts of the hosting country repository program. The FEBEX (Full-scale Engineered Barrier Experiment in Crystalline Host Rock) project is a large-scale heater test experiment originated by the Spanish radioactive waste management agency (Empresa Nacional de Residuos Radiactivos S.A. – ENRESA) at the Grimsel Test Site (GTS) URL in Switzerland. The project was subsequently managed by CIEMAT. FEBEX-DP is a concerted effort of various international partners working on the evaluation of sensor data and characterization of samples obtained during the course of this field test and subsequent dismantling. The main purpose of these field-scale experiments is to evaluate feasibility for creation of an engineered barrier system (EBS) with a horizontal configuration according to the Spanish concept of deep geological disposal of high-level radioactive waste in crystalline rock. Another key aspect of this project is to improve the knowledge of coupled processes such as thermal-hydro-mechanical (THM) and thermal-hydro-chemical (THC) operating in the near-field environment. The focus of these is on model development and validation of predictions through model implementation in computational tools to simulate coupled THM and THC processes.

  14. Physical Activity and Youth with Disabilities: Barriers and Supports

    Science.gov (United States)

    Block, Martin E.; Taliaferro, Andrea; Moran, Tom

    2013-01-01

    Physical activity and active use of leisure time is important for everyone but particularly important for youth with disabilities. Unfortunately, youth with disabilities often have a difficult time or are even excluded from participating in physical activity due to limited physical and cognitive skills, attitudinal barriers in the community, lack…

  15. Buckling of thermally fluctuating spherical shells: Parameter renormalization and thermally activated barrier crossing

    Science.gov (United States)

    Baumgarten, Lorenz; Kierfeld, Jan

    2018-05-01

    We study the influence of thermal fluctuations on the buckling behavior of thin elastic capsules with spherical rest shape. Above a critical uniform pressure, an elastic capsule becomes mechanically unstable and spontaneously buckles into a shape with an axisymmetric dimple. Thermal fluctuations affect the buckling instability by two mechanisms. On the one hand, thermal fluctuations can renormalize the capsule's elastic properties and its pressure because of anharmonic couplings between normal displacement modes of different wavelengths. This effectively lowers its critical buckling pressure [Košmrlj and Nelson, Phys. Rev. X 7, 011002 (2017), 10.1103/PhysRevX.7.011002]. On the other hand, buckled shapes are energetically favorable already at pressures below the classical buckling pressure. At these pressures, however, buckling requires to overcome an energy barrier, which only vanishes at the critical buckling pressure. In the presence of thermal fluctuations, the capsule can spontaneously overcome an energy barrier of the order of the thermal energy by thermal activation already at pressures below the critical buckling pressure. We revisit parameter renormalization by thermal fluctuations and formulate a buckling criterion based on scale-dependent renormalized parameters to obtain a temperature-dependent critical buckling pressure. Then we quantify the pressure-dependent energy barrier for buckling below the critical buckling pressure using numerical energy minimization and analytical arguments. This allows us to obtain the temperature-dependent critical pressure for buckling by thermal activation over this energy barrier. Remarkably, both parameter renormalization and thermal activation lead to the same parameter dependence of the critical buckling pressure on temperature, capsule radius and thickness, and Young's modulus. Finally, we study the combined effect of parameter renormalization and thermal activation by using renormalized parameters for the energy

  16. Barriers to investments in energy saving technologies. Case study for the industry

    NARCIS (Netherlands)

    Masselink, Dirk Jan

    2007-01-01

    To realise future energy saving targets, the government needs to increase energy reduction rates. One option to increase energy savings is found in removing barriers to investments in cost-effective energy saving technologies. Many technologies save energ

  17. Barriers to renewable energy development: A case study of large-scale wind energy in Saskatchewan, Canada

    International Nuclear Information System (INIS)

    Richards, Garrett; Noble, Bram; Belcher, Ken

    2012-01-01

    Renewable energy is receiving increased attention as a viable alternative to non-renewable electrical generation, however, meeting global energy demands will require a more ambitious renewable energy program than is currently the case. There have been several reviews of potential technological, economic, social, or public barriers and solutions to renewable energy investment. Although important, there is also need for multi-dimensional analyses of these barriers and identification of the most significant underlying barriers if viable solutions are to be developed. In this paper we apply a theoretical framework to examine stakeholder's perceptions and understanding of the barriers to wind energy development in Saskatchewan, Canada. We identify and examine the most significant underlying barriers to investment in renewable energy and the interactions between those barriers. Results show a number of perceived barriers to wind energy investment, however, these barriers can be explained in large part by knowledge barriers, if not disagreement over whether the current level of investment in wind energy is sufficient. We show that barriers to renewable energy cannot be explained solely by technological, social, political, or economic factors in isolation, and that a multi-dimensional approach, identifying and explaining the underlying sources of these barriers, is necessary to develop viable solutions. - Highlights: ► Meeting future wind energy objectives requires an ambitious investment program. ► A framework is applied to identify and explain perceived barriers to wind energy. ► Stakeholders perceived technological and political barriers as the most significant. ► These could be explained by knowledge barriers and complacency with the status quo. ► Even with additional investment these underlying barriers will constrain progress.

  18. Adolescent Girls' Perceived Barriers to Participation in Physical Activity

    Science.gov (United States)

    Dwyer, John J. M.; Allison, Kenneth R.; Goldenberg, Ellie R.; Fein, Allan J.; Yoshida, Karen K.; Boutilier, Marie A.

    2006-01-01

    Research shows a decline in physical activity levels during adolescence, particularly among girls. This study explored perceived barriers to participation in moderate and vigorous physical activity among adolescent girls who live in a large ethnoracially and socioeconomically diverse city. A total of 73 adolescent girls in Toronto participated in…

  19. Parametric modeling of energy filtering by energy barriers in thermoelectric nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Zianni, Xanthippi, E-mail: xzianni@teiste.gr, E-mail: xzianni@gmail.com [Department of Aircraft Technology, Technological Educational Institution of Sterea Ellada, 34400 Psachna (Greece); Department of Microelectronics, INN, NCSR “Demokritos,” 15310 Athens (Greece); Narducci, Dario [Department of Materials Science, University of Milano Bicocca, 20125 Milano (Italy)

    2015-01-21

    We present a parametric modeling of the thermoelectric transport coefficients based on a model previously used to interpret experimental measurements on the conductivity, σ, and Seebeck coefficient, S, in highly Boron-doped polycrystalline Si, where a very significant thermoelectric power factor (TPF) enhancement was observed. We have derived analytical formalism for the transport coefficients in the presence of an energy barrier assuming thermionic emission over the barrier for (i) non-degenerate and (ii) degenerate one-band semiconductor. Simple generic parametric equations are found that are in agreement with the exact Boltzmann transport formalism in a wide range of parameters. Moreover, we explore the effect of energy barriers in 1-d composite semiconductors in the presence of two phases: (a) the bulk-like phase and (b) the barrier phase. It is pointed out that significant TPF enhancement can be achieved in the composite structure of two phases with different thermal conductivities. The TPF enhancement is estimated as a function of temperature, the Fermi energy position, the type of scattering, and the barrier height. The derived modeling provides guidance for experiments and device design.

  20. Science Activities in Energy: Wind Energy.

    Science.gov (United States)

    Oak Ridge Associated Universities, TN.

    Included in this science activities energy package are 12 activities related to wind energy for elementary students. Each activity is outlined on a single card and is introduced by a question. Topics include: (1) At what time of day is there enough wind to make electricity where you live?; (2) Where is the windiest spot on your schoolground?; and…

  1. Barriers associated with reduced physical activity in COPD patients.

    Science.gov (United States)

    Amorim, Priscila Batista; Stelmach, Rafael; Carvalho, Celso Ricardo Fernandes; Fernandes, Frederico Leon Arrabal; Carvalho-Pinto, Regina Maria; Cukier, Alberto

    2014-10-01

    To evaluate the ability of COPD patients to perform activities of daily living (ADL); to identify barriers that prevent these individuals from performing ADL; and to correlate those barriers with dyspnea severity, six-minute walk test (6MWT), and an ADL limitation score. In COPD patients and healthy, age-matched controls, the number of steps, the distance walked, and walking time were recorded with a triaxial accelerometer, for seven consecutive days. A questionnaire regarding perceived barriers and the London Chest Activity of Daily Living (LCADL) scale were used in order to identify the factors that prevent the performance of ADL. The severity of dyspnea was assessed with two scales, whereas submaximal exercise capacity was determined on the basis of the 6MWT. We evaluated 40 COPD patients and 40 controls. In comparison with the control values, the mean walk time was significantly shorter for COPD patients (68.5 ± 25.8 min/day vs. 105.2 ± 49.4 min/day; p barriers to performing ADL were lack of infrastructure, social influences, and lack of willpower. The 6MWT distance correlated with the results obtained with the accelerometer but not with the LCADL scale results. Patients with COPD are less active than are healthy adults of a comparable age. Physical inactivity and the barriers to performing ADL have immediate implications for clinical practice, calling for early intervention measures.

  2. Energy barriers for diffusion on heterogeneous stepped metal surfaces: Ag/Cu(110)

    International Nuclear Information System (INIS)

    Sbiaai, K.; Boughaleb, Y.; Mazroui, M.; Hajjaji, A.; Kara, A.

    2013-01-01

    In this paper we investigated the diffusion of Ag adatom by computing the energy barriers for many elementary diffusive processes which are likely to happen near to the step edge on Cu (110). The barriers are calculated by means of molecular dynamics simulation by using embedded atom potentials. The proximity to steps alters these barriers considerably, and very different results may be expected. In fact, our numerical calculations show that the diffusion via jump process along step edge is predominant for Ag/Cu(110) and the diffusion over the step occurs sometimes, but only via exchange mechanisms. The adatom diffusion across channels is difficult due to the high value of activation energy required (around 1 eV). Furthermore, we found the Ehrlich–Schwoebel barrier for diffusion around 120 meV in order to descend via exchange process and of the order of 170 meV via hopping mode. This aspect may have a strong influence on the growth character. In general our results suggest that, for our metal system, diffusion mechanism may be important for mass transport across the steps. Implications of these findings are discussed. - Highlights: • Study of adatom diffusion near the step edge • The diffusion along channel is enhanced through jump process. • Arrhenius law is satisfied for a wide range of temperature (310–600 K)

  3. Barriers to energy efficiency improvement. Empirical evidence from small-and-medium-sized enterprises in China

    Energy Technology Data Exchange (ETDEWEB)

    Kostka, Genia; Moslener, Ulf; Andreas, Jan G.

    2012-07-01

    This paper analyzes barriers for energy efficiency investments for small-and medium-sized enterprises (SMEs) in China. Based on a survey of 480 SMEs in Zhejiang Province, this study assesses financial, informational, and organizational barriers for energy efficiency investments in the SME sector. The conventional view has been that the lack of appropriate financing mechanisms particularly hinders SMEs to adopt cost-effective energy efficiency measures. As such, closing the financing gap for SMEs is seen as a prerequisite in order to promote energy efficiency in the sector. The econometric estimates of this study, however, suggest that access to information is an important determinant of investment outcomes, while this is less clear with respect to financial and organizational factors. More than 40 percent of enterprises in the sample declared that that they are not aware of energy saving equipments or practices in their respective business area, indicating that there are high transaction costs for SMEs to gather, assess, and apply information about energy saving potentials and relevant technologies. One implication is that the Chinese government may assume an active role in fostering the dissemination of energy-efficiency related information in the SME sector. (orig.)

  4. Physical Activity Promotion, Beliefs, and Barriers Among Australasian Oncology Nurses.

    Science.gov (United States)

    Keogh, Justin W L; Pühringer, Petra; Olsen, Alicia; Sargeant, Sally; Jones, Lynnette M; Climstein, Mike

    2017-03-01

    To describe the physical activity (PA) promotion practices, beliefs, and barriers of Australasian oncology nurses and gain preliminary insight into how PA promotion practices may be affected by the demographics of the nurses.
. Cross-sectional survey.
. Australia and New Zealand.
. 119 registered oncology nurses.
. Self-reported online survey completed once per participant.
. Questions assessed the PA promotion beliefs (e.g., primary healthcare professionals responsible for PA promotion, treatment stage), PA benefits (e.g., primary benefits, evidence base), and PA promotion barriers of oncology nurses.
. Oncology nurses believed they were the major providers of PA advice to their patients. They promoted PA prior to, during, and post-treatment. The three most commonly cited benefits of PA for their patients were improved quality of life, mental health, and activities of daily living. Lack of time, lack of adequate support structures, and risk to patient were the most common barriers to PA promotion. Relatively few significant differences in the oncology nurses' PA promotion practices, beliefs, and barriers were observed based on hospital location or years of experience.
. Despite numerous barriers, Australasian oncology nurses wish to promote PA to their patients with cancer across multiple treatment stages because they believe PA is beneficial for their patients.
. Hospitals may need to better support oncology nurses in promoting PA to their patients and provide better referral pathways to exercise physiologists and physiotherapists.

  5. Understanding energy efficiency barriers in Ukraine: Insights from a survey of commercial and industrial firms

    International Nuclear Information System (INIS)

    Timilsina, Govinda R.; Hochman, Gal; Fedets, Iryna

    2016-01-01

    Improvement of energy efficiency is an important element of energy policy for a sustainable supply of energy in Ukraine. However, the country is facing several challenges to the large-scale deployment of energy efficient technologies. We conducted a two-stage quota sample survey of 509 commercial and industrial firms of all regions of Ukraine to understand the barriers to energy efficiency improvements. Our study finds that more than two-thirds of the commercial and industrial firms in the country view improvement of energy efficiency very important to their business. However, due to several barriers they are unable to realize the improvements of energy efficiency. Among the 19 potential barriers investigated in the study, the survey results show that high upfront investment requirement, lack of government policies to support energy efficiency improvements, higher cost of capital, and lack of information and awareness are the most critical barriers to the improvement of energy efficiency in the industrial and commercial sectors in Ukraine. - Highlights: • Despite attractiveness, large scale deployment of energy efficiency is lacking. • Several barriers are responsible for slow implementation of energy efficiency. • Understanding the barriers from the field is crucial to design effective policies. • A survey of commercial and industrial firms reveals the key barriers. • Financial barriers are the main hurdles to adopt energy efficient technologies.

  6. Partitioning of methyl internal rotational barrier energy of ...

    Indian Academy of Sciences (India)

    The nature of methyl internal rotational barrier in thioacetaldehyde has been investigated by relaxation effect, natural bond orbital (NBO) analysis and Pauling exchange interactions. The true experimental barrier can be obtained by considering fully relaxed rotation. Nuclear-electron attraction term is a barrier forming term in ...

  7. Can human activities alter the drowning fate of barrier islands?

    Science.gov (United States)

    Lorenzo-Trueba, J.; Ashton, A. D.; Jin, D.; Hoagland, P.; Kite-Powell, H.

    2012-12-01

    Low-lying coastal barriers face an uncertain future over the coming century and beyond as sea levels rise, with many projections suggesting end-of-century rates of sea-level rise as high or higher than 1 cm/yr. Geologically, such rates of sea-level rise have been experienced several thousand years ago and we can use our understanding of geological processes and sedimentary evidence to help unravel the dynamics of natural barriers experiencing sea-level rise. Along many modern coastal barriers, however, anthropic change, such as beach nourishment, dune construction, and emplacement of hard structures, plays a dominant role in coastline dynamics. A fundamental question to be addressed is whether human activities intended to preserve infrastructure and beach recreation may make wholesale collapse, or 'drowning,' of barrier systems more likely. Here we present a numerical modeling tool that couples natural processes and the human responses to these changes (and the subsequent of human responses on natural processes). Recent theoretical model development suggests that barriers are intrinsically morphodynamic features, responding to sea-level rise in complex ways through the interactions of marine processes and barrier overwash. Undeveloped coastal barriers would therefore respond to an accelerated sea-level rise in complex, less predictable manners than suggested by existing long-term models. We have developed a model that examines non-equilibrium cross-shore evolution of barrier systems at decadal to centennial temporal scales, focusing on the interactions between processes of shoreface evolution and overwash deposition. Model responses demonstrate two means of barrier collapse during sea-level rise: 'height drowning', which occurs when overwash fluxes are insufficient to maintain the landward migration rate required to keep in pace with sea-level rise, and 'width drowning', which occurs when the shoreface response is insufficient to maintain the barrier geometry

  8. Measuring Perceived Benefits and Perceived Barriers for Physical Activity

    Science.gov (United States)

    Brown, Seth A.

    2005-01-01

    Objectives: To evaluate the psychometric properties and relationship to physical activity levels of the Exercise Benefits/Barriers Scale (EBBS) among college students. Methods: A total of 398 college students completed the EBBS and a measure of self-efficacy, the Physical Exercise Self-Efficacy Scale. In addition, a subsample of 275 students also…

  9. Barriers and Motivators to Physical Activity among African American Women

    Science.gov (United States)

    James, Delores C. S.; Efunbumi, Orisatalabi; Harville, Cedric; Sears, Cynthia

    2014-01-01

    The goals of the study were to identify the barriers and motivators for physical activity (PA) and to assess whether these factors vary by weight status. A self-administered survey was completed by 413 African American women. Each woman provided verbal informed consent and was weighed and measured by a research team member. The participants' mean…

  10. Overcoming energy efficiency barriers through systems approach—A conceptual framework

    International Nuclear Information System (INIS)

    Chai, Kah-Hin; Yeo, Catrina

    2012-01-01

    In this paper we propose a framework which categorizes energy efficiency barriers based on the stage at which the barriers exist. Barriers to energy efficiency have been widely studied but to our knowledge, except for a few studies, we found inadequate consideration for barrier–barrier interactions when proposing policy measures for improving energy efficiency. Leveraging systems thinking's power as a problem solver which identifies underlying structure that explains (similar) patterns of behavior in a variety of different situations, we attempted to identify patterns of barriers to adoption of energy efficiency measures in industrial companies. Inspired by systems thinking, the proposed framework has four stages, namely, Motivation, Capability, Implementation and Results, as well as a feedback loop. Using a case study, we show that following the four stages will lead to positive feedback for future energy efficiency implementations. The framework highlights the interconnected nature of the barriers and a need for policymakers to address these barriers in a holistic manner. We argue that the overall effectiveness of energy efficiency policies is only as strong as the weakest link in the four-stage framework. This differs from most prior research that addressed barriers in isolation, where a solution is proposed for each of the barriers without considering the relationship between the barriers. Our framework also offers a way to understand the roles and responsibilities of major stakeholders such as governments and energy service companies (ESCOs) in driving energy efficiency. This allows the assessment and identification of weak links in energy efficiency policies. - Highlights: ► We propose a systems approach to overcome energy efficiency barriers. ► Barriers are grouped into Motivation, Capability, Implementation and Results. ► Case study shows that there is a feedback loop from Results to Motivation. ► Current Results will affect future Motivation.

  11. Study of Quasielastic scattering for 7Li+159Tb at around- barrier energies

    Directory of Open Access Journals (Sweden)

    Mukherjee A.

    2017-01-01

    Full Text Available Quasielastic scattering cross sections for the reaction 7Li+159Tb have been measured at large backangles, at energies around the Coulomb barrier. The quasielastic barrier distribution has been extracted from the measured quasielastic scattering excitation function, including and excluding α particle contribution. The peak of the quasielastic barrier distribution including α particle contribution shows a shift towards higher energy compared to the peak of the distribution without α particles. The quasielastic barrier distribution when compared to the calculated fusion barrier distribution, appears to show reasonable agreement for the system.

  12. Applications of Skyrme energy-density functional to fusion reactions spanning the fusion barriers

    International Nuclear Information System (INIS)

    Liu Min; Wang, Ning; Li Zhuxia; Wu Xizhen; Zhao Enguang

    2006-01-01

    The Skyrme energy density functional has been applied to the study of heavy-ion fusion reactions. The barriers for fusion reactions are calculated by the Skyrme energy density functional with proton and neutron density distributions determined by using restricted density variational (RDV) method within the same energy density functional together with semi-classical approach known as the extended semi-classical Thomas-Fermi method. Based on the fusion barrier obtained, we propose a parametrization of the empirical barrier distribution to take into account the multi-dimensional character of real barrier and then apply it to calculate the fusion excitation functions in terms of barrier penetration concept. A large number of measured fusion excitation functions spanning the fusion barriers can be reproduced well. The competition between suppression and enhancement effects on sub-barrier fusion caused by neutron-shell-closure and excess neutron effects is studied

  13. Deep inelastic collisions at near-barrier energies and search for cold donor-fragment production

    International Nuclear Information System (INIS)

    Chatterjee, M.B.

    1992-01-01

    Deep inelastic collisions in the near barrier energies of the mass asymmetric systems are of importance since controversial results on energy partition are being reported. Energy dissipation and the partition of dissipated energy among the reaction partners are of interest. Search for cold donor-fragment production at near barrier energies were carried out on a mass asymmetric system like Ni+Pb. (author). 13 refs., 8 figs

  14. Barrier-beliefs about physical activity in active and inactive adults : an explorative study

    NARCIS (Netherlands)

    Bouma, Adrie

    2018-01-01

    Objectives: Perceived barriers are often a reason why people do not start physical activity or relapse to inactivity. From a psychological perspective, barriers can be seen as beliefs about what is obstructing people’s behavior. To understand inactivity and relapse from physical activity, this study

  15. Consistent energy barrier distributions in magnetic particle chains

    International Nuclear Information System (INIS)

    Laslett, O.; Ruta, S.; Chantrell, R.W.; Barker, J.; Friedman, G.; Hovorka, O.

    2016-01-01

    We investigate long-time thermal activation behaviour in magnetic particle chains of variable length. Chains are modelled as Stoner–Wohlfarth particles coupled by dipolar interactions. Thermal activation is described as a hopping process over a multidimensional energy landscape using the discrete orientation model limit of the Landau–Lifshitz–Gilbert dynamics. The underlying master equation is solved by diagonalising the associated transition matrix, which allows the evaluation of distributions of time scales of intrinsic thermal activation modes and their energy representation. It is shown that as a result of the interaction dependence of these distributions, increasing the particle chain length can lead to acceleration or deceleration of the overall relaxation process depending on the initialisation procedure.

  16. An activated barrier for protection of special nuclear materials in vital areas

    International Nuclear Information System (INIS)

    Timm, R.E.; Miranda, J.E.

    1984-01-01

    The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide the system delay. The principal advantages of the activated barrier are: (1) it provides an order of magnitude improvement in delay over that of a fixed barrier, (2) it can be added to existing vital areas with a minimum of renovations, (3) existing operations are minimally impacted, and (4) health and safety risks are virtually nonexistent. Hardening of the vital areas using the ADS was accomplished in a costeffective manner

  17. Activated barrier for protection of special nuclear materials in vital areas

    International Nuclear Information System (INIS)

    Timm, R.E.; Miranda, J.E.; Reigle, D.L.; Valente, A.D.

    1984-01-01

    The Argonne National Laboratory and Sandia National Laboratory have recently installed an activated barrier, the Access Denial System (ADS) for the upgrade of safeguards of special nuclear materials. The technology of this system was developed in the late 70's by Sandia National Laboratory-Albuquerque. The installation was the first for the Department of Energy. Subsequently, two additional installations have been completed. The Access Denial System, combined with physical restraints, provide the system delay. The principal advantages of the activated barrier are: (1) it provides an order of magnitude improvement in delay over that of a fixed barrier, (2) it can be added to existing vital areas with a minimum of renovations, (3) existing operations are minimally impacted, and (4) health and safety risks are virtually nonexistent. Hardening of the vital areas using the ADS was accomplished in a cost-effective manner. 3 references, 1 figure, 1 table

  18. Fusion of 6Li with 159Tb at near-barrier energies

    International Nuclear Information System (INIS)

    Pradhan, M. K.; Mukherjee, A.; Basu, P.; Goswami, A.; Kshetri, R.; Roy, Subinit; Chowdhury, P. Roy; Sarkar, M. Saha; Palit, R.; Parkar, V. V.; Santra, S.; Ray, M.

    2011-01-01

    Complete and incomplete fusion cross sections for 6 Li + 159 Tb have been measured at energies around the Coulomb barrier by the γ-ray method. The measurements show that the complete fusion cross sections at above-barrier energies are suppressed by ∼34% compared to coupled-channel calculations. A comparison of the complete fusion cross sections at above-barrier energies with the existing data for 11,10 B + 159 Tb and 7 Li + 159 Tb shows that the extent of suppression is correlated with the α separation energies of the projectiles. It has been argued that the Dy isotopes produced in the reaction 6 Li + 159 Tb at below-barrier energies are primarily due to the d transfer to unbound states of 159 Tb, while both transfer and incomplete fusion processes contribute at above-barrier energies.

  19. Reducing barriers to energy efficiency in the German higher education sector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Boede, U.

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German higher education (HE) sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of six case studies of energy management in German universities. The results are analysed using the theoretical framework developed for the BARRIERS project (Sorrell et al., 2000). The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the sector may be improved. The results of the study for the higher education sector in Germany are summarised in this executive summary under the following headings: - Characterising the higher education sector; - Case studies of energy management in the German higher education sector; - Evidence of barriers in the German higher education sector; - The role of energy service companies in the higher education sector; - Policy implications. (orig.)

  20. Reducing barriers to energy efficiency in the German higher education sector. Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Boede, U.

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German higher education (HE) sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of six case studies of energy management in German universities. The results are analysed using the theoretical framework developed for the BARRIERS project (Sorrell et al., 2000). The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the sector may be improved. The results of the study for the higher education sector in Germany are summarised in this executive summary under the following headings: - Characterising the higher education sector; - Case studies of energy management in the German higher education sector; - Evidence of barriers in the German higher education sector; - The role of energy service companies in the higher education sector; - Policy implications. (orig.)

  1. Reducing barriers to energy efficiency in the German mechanical engineering sector. Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Boede, U.

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German mechanical engineering (ME) sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of four case studies of energy management in German companies in the ME sector. The results are analysed using the theoretical framework developed for the BARRIERS project. The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the ME sector may be improved. The results of the study for the ME sector in Germany are summarised in this executive summary under the following headings: - Characterising the mechanical engineering sector; - Case studies of energy management in the German mechanical engineering sector; - Evidence of barriers in the German mechanical engineering sector; - The role of energy service companies in the mechanical engineering sector; - Policy implications. (orig.)

  2. Reducing barriers to energy efficiency in the German brewing sector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J; Boede, U; Ostertag, K; Radgen, P

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German brewing sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of five case studies of energy management in German breweries. The results are analysed using the theoretical framework developed for the BARRIERS project. The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the brewing sector may be improved. The results of the study for the brewing sector in Germany are summarised in this executive summary under the following headings: - Characterising the brewing sector - Case studies of energy management in the German brewing sector; - Evidence of barriers in the German brewing sector; - The role of energy service companies in the brewing sector; - Policy implications. (orig.)

  3. Reducing barriers to energy efficiency in the German mechanical engineering sector. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Boede, U.

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German mechanical engineering (ME) sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of four case studies of energy management in German companies in the ME sector. The results are analysed using the theoretical framework developed for the BARRIERS project. The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the ME sector may be improved. The results of the study for the ME sector in Germany are summarised in this executive summary under the following headings: - Characterising the mechanical engineering sector; - Case studies of energy management in the German mechanical engineering sector; - Evidence of barriers in the German mechanical engineering sector; - The role of energy service companies in the mechanical engineering sector; - Policy implications. (orig.)

  4. Reducing barriers to energy efficiency in the German brewing sector. Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Schleich, J.; Boede, U.; Ostertag, K.; Radgen, P.

    2000-12-01

    This report describes the empirical research into barriers to energy efficiency in the German brewing sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of five case studies of energy management in German breweries. The results are analysed using the theoretical framework developed for the BARRIERS project. The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the brewing sector may be improved. The results of the study for the brewing sector in Germany are summarised in this executive summary under the following headings: - Characterising the brewing sector; - Case studies of energy management in the German brewing sector; - Evidence of barriers in the German brewing sector; - The role of energy service companies in the brewing sector; - Policy implications. (orig.)

  5. Barriers associated with reduced physical activity in COPD patients

    Directory of Open Access Journals (Sweden)

    Priscila Batista Amorim

    2014-10-01

    Full Text Available OBJECTIVE: To evaluate the ability of COPD patients to perform activities of daily living (ADL; to identify barriers that prevent these individuals from performing ADL; and to correlate those barriers with dyspnea severity, six-minute walk test (6MWT, and an ADL limitation score. METHODS: In COPD patients and healthy, age-matched controls, the number of steps, the distance walked, and walking time were recorded with a triaxial accelerometer, for seven consecutive days. A questionnaire regarding perceived barriers and the London Chest Activity of Daily Living (LCADL scale were used in order to identify the factors that prevent the performance of ADL. The severity of dyspnea was assessed with two scales, whereas submaximal exercise capacity was determined on the basis of the 6MWT. RESULTS: We evaluated 40 COPD patients and 40 controls. In comparison with the control values, the mean walk time was significantly shorter for COPD patients (68.5 ± 25.8 min/day vs. 105.2 ± 49.4 min/day; p < 0.001, as was the distance walked (3.9 ± 1.9 km/day vs. 6.4 ± 3.2 km/day; p < 0.001. The COPD patients also walked fewer steps/day. The most common self-reported barriers to performing ADL were lack of infrastructure, social influences, and lack of willpower. The 6MWT distance correlated with the results obtained with the accelerometer but not with the LCADL scale results. CONCLUSIONS: Patients with COPD are less active than are healthy adults of a comparable age. Physical inactivity and the barriers to performing ADL have immediate implications for clinical practice, calling for early intervention measures.

  6. Culture X: addressing barriers to physical activity in Samoa.

    Science.gov (United States)

    Heard, Emma Marie; Auvaa, Leveti; Conway, Brooke A

    2017-08-01

    There is an urgent need to address the epidemic rates of non-communicable diseases globally, and the Pacific Island region is of particular concern. Increasing physical activity participation plays an important role in reducing some of the key risk factors for non-communicable diseases including obesity and being overweight. In order to address low levels of physical activity, it is essential to understand the key barriers and facilitating factors experienced by specific population groups. The purpose of this study is to investigate key facilitating factors for participation in a dance aerobic initiative, Culture X, developed in the Pacific Island country, Samoa. The study further aims to understand ways in which the programme assists participants in addressing barriers to physical activity. Face-to-face interviews running from 10 to 20 min were conducted with 28 Culture X participants in order to gain a deep understanding of participants' personal perspectives with regard to barriers and facilitating factors to physical activity. Findings suggest the inclusion of key cultural components (including, traditional dance moves and music, prayer, community orientation and family inclusiveness) were integral for supporting ongoing participation in Culture X. These components further assisted participants in addressing important personal and social barriers to physical activity (including lack of motivation and enjoyment, lack of confidence, time management, family and social commitments and lack of support). This study highlights creative ways that health promotion in the Pacific Island region can encourage physical activity and informs health promotion literature regarding the importance of placing local culture at the heart of behaviour change initiatives. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Technical Barriers, Gaps,and Opportunities Related to Home Energy Upgrade Market Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Marcus V.A. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2011-11-01

    This report outlines the technical barriers, gaps, and opportunities that arise in executing home energy upgrade market delivery approaches, as identified through research conducted by the U.S. Department of Energy's Building America program.

  8. Financing energy SMEs in Ghana and Senegal: Outcomes, barriers and prospects

    DEFF Research Database (Denmark)

    Haselip, James Arthur; Desgain, Denis DR; Mackenzie, Gordon A.

    2014-01-01

    enterprises (energy SMEs). These assumptions were (1) that the lack of affordable local financing presented the most significant barrier to setting up and expanding energy SMEs, and (2) that these barriers would be overcome by a ‘demonstration effect’ whereby successful businesses, supported by donor...

  9. Unsupervised Calculation of Free Energy Barriers in Large Crystalline Systems

    Science.gov (United States)

    Swinburne, Thomas D.; Marinica, Mihai-Cosmin

    2018-03-01

    The calculation of free energy differences for thermally activated mechanisms in the solid state are routinely hindered by the inability to define a set of collective variable functions that accurately describe the mechanism under study. Even when possible, the requirement of descriptors for each mechanism under study prevents implementation of free energy calculations in the growing range of automated material simulation schemes. We provide a solution, deriving a path-based, exact expression for free energy differences in the solid state which does not require a converged reaction pathway, collective variable functions, Gram matrix evaluations, or probability flux-based estimators. The generality and efficiency of our method is demonstrated on a complex transformation of C 15 interstitial defects in iron and double kink nucleation on a screw dislocation in tungsten, the latter system consisting of more than 120 000 atoms. Both cases exhibit significant anharmonicity under experimentally relevant temperatures.

  10. A novel approach for barriers to industrial energy efficiency

    NARCIS (Netherlands)

    Cagno, E.; Worrell, E.; Trianni, A.; Pugliese, G.

    2013-01-01

    A critical review of the literature highlighted the need for a new taxonomy encompassing the most relevant barriers stemmed from previous studies, and accounting for interactions and independences of the barriers to avoid overlaps and implicit interactions. Based on an extensive literature review

  11. Barriers to and drivers for energy efficiency in the Swedish foundry industry

    International Nuclear Information System (INIS)

    Rohdin, Patrik; Thollander, Patrik; Solding, Petter

    2007-01-01

    Despite the need for increased industrial energy efficiency, studies indicate that cost-efficient energy conservation measures are not always implemented, explained by the existence of barriers to energy efficiency. This paper investigates the existence of different barriers to and driving forces for the implementation of energy efficiency measures in the energy intensive Swedish foundry industry. The overall results from a questionnaire show that limited access to capital constitutes by far the largest barrier to energy efficiency according to the respondents. A comparison between group-owned and privately owned foundries shows that, except for limited access to capital, they face different high-ranked barriers. While barriers within group owned companies are more related to organizational problems, barriers within private foundries are more related to information problems. This study also found that energy consultants or other actors working with energy issues in foundries are of major importance in overcoming the largest barriers, as the foundries consider them trustworthy. They may thus help the foundries overcome organizational problems such as lack of sub-metering and lack of budget funds by quantifying potential energy efficiency investments. The two, by far, most important drivers were found to be people with real ambition and long-term energy strategies

  12. Key Barriers to the Implementation of Solar Energy in Nigeria: A Critical Analysis

    Science.gov (United States)

    Abdullahi, D.; Suresh, S.; Renukappa, S.; Oloke, D.

    2017-08-01

    Nigeria, potentially, has abundant sunshine throughout the year, making it full thirst for solar energy generation. Even though, the country’s solar energy projects have not realised a fair result over the years, due to many barriers associated with initiatives implementation. Therefore, the entire power sector remains incapacitated to generate, transmit and distribute a clean, affordable and sustainable energy to assist economic growth. The research integrated five African counterpart’s solar energy initiatives, barriers, policies and strategies adopted as a lesson learned to Nigeria. Inadequate solar initiative’s research, lack of technological know-how, short-term policies, lack of awareness and political instability are the major barriers that made the implementation of solar initiatives almost impossible in Nigeria. The shock of the barriers therefore, constitutes a major negative contribution to the crippling of the power sector in the state. Future research will concentrate on initiatives for mitigating solar and other renewable energy barriers.

  13. Attempting to be active: Self-efficacy and barrier limitation differentiate activity levels of working mothers.

    Science.gov (United States)

    Gierc, Madelaine; Locke, Sean; Jung, Mary; Brawley, Lawrence

    2016-07-01

    Working mothers are less physically active than working women without children and mothers who do not work. The purpose of this study was to examine concurrent self-regulatory efficacy and barriers to physical activity in a sample of working mothers. Women completed a mixed-methods survey which included measures of physical activity, concurrent self-regulatory efficacy, and barriers. Sufficiently active women experienced significantly greater concurrent self-regulatory efficacy and significantly less barrier limitation and frequency. No significant group differences were found for age, domestic duties performed, and children's extracurricular activities. Thematic analysis of barriers revealed six themes of common and unique factors, including limited time and family activities. © The Author(s) 2014.

  14. Neighborhood disadvantage, physical activity barriers, and physical activity among African American breast cancer survivors

    Directory of Open Access Journals (Sweden)

    Antwan Jones

    2015-01-01

    Higher renter rates and individual barriers both contribute to lower levels of physical activity in African American breast cancer survivors. These data suggest that the potential for constant residential turnover (via rentership and perceived barriers may increase physical inactivity even where facilities may be available.

  15. Energy transfer of excitons between quantum wells separated by a wide barrier

    International Nuclear Information System (INIS)

    Lyo, S. K.

    2000-01-01

    We present a microscopic theory of the excitonic Stokes and anti-Stokes energy-transfer mechanisms between two widely separated unequal quantum wells with a large energy mismatch (Δ) at low temperatures (T). Several important intrinsic energy-transfer mechanisms have been examined, including dipolar coupling, real and virtual photon-exchange coupling, and over-barrier ionization of the excitons via exciton-exciton Auger processes. The transfer rate is calculated as a function of T and the center-to-center distance d between the wells. The rates depend sensitively on T for plane-wave excitons. For localized excitons, the rates depend on T only through the T dependence of the exciton localization radius. For Stokes energy transfer, the dominant energy transfer occurs through a photon-exchange interaction, which enables the excitons from the higher-energy wells to decay into free electrons and holes in the lower-energy wells. The rate has a slow dependence on d, yielding reasonable agreement with recent data from GaAs/Al x Ga 1-x As quantum wells. The dipolar rate is about an order of magnitude smaller for large d (e.g., d=175Aa) with a stronger range dependence proportional to d -4 . However, the latter can be comparable to the radiative rate for small d (e.g., d≤80Aa). For anti-Stokes transfer through exchange-type (e.g., dipolar and photon-exchange) interactions, we show that thermal activation proportional to exp(-Δ/k B T) is essential for the transfer, contradicting a recent nonactivated result based on the Fo''rster-Dexter's spectral-overlap theory. Phonon-assisted transfer yields a negligibly small rate. On the other hand, energy transfer through over-barrier ionization of excitons via Auger processes yields a significantly larger nonactivated rate which is independent of d. The result is compared with recent data

  16. 6,7Li + 28Si total reaction cross sections at near barrier energies

    International Nuclear Information System (INIS)

    Pakou, A.; Musumarra, A.; Pierroutsakou, D.; Alamanos, N.; Assimakopoulos, P.A.; Divis, N.; Doukelis, G.; Gillibert, A.; Harissopulos, S.; Kalyva, G.; Kokkoris, M.; Lagoyannis, A.; Mertzimekis, T.J.; Nicolis, N.G.; Papachristodoulou, C.; Perdikakis, G.; Roubos, D.; Rusek, K.; Spyrou, S.; Zarkadas, Ch.

    2007-01-01

    Total reaction cross section measurements for the 6,7 Li + 28 Si systems have been performed at near-barrier energies. The results indicate that, with respect to the potential anomaly at barrier, 6 Li and 7 Li on light targets exhibit similar energy dependence on the imaginary potential. Comparisons are made with 6,7 Li cross sections on light and heavy targets, extracted via previous elastic scattering measurements and also with CDCC calculations. Energy dependent parametrisations are also obtained for total reaction cross sections of 6,7 Li on Si, as well as on any target, at near barrier energies

  17. Barriers, activities and participation: Incorporating ICF into service planning datasets.

    LENUS (Irish Health Repository)

    O'Donovan, MA

    2009-05-21

    Purpose. Guided by the World Health Organization\\'s International Classification of Functioning, Disability and Health (ICF), a measure of activity and participation (MAP) was developed and incorporated into the National Physical and Sensory Disability Database in Ireland. The aims of this article are to investigate and explore the relationship between the barriers, participation restriction and functioning levels experienced by people with disabilities. Method. Seven thousand five hundred and sixty-two personal interviews with people meeting specific eligibility criteria for registering onto the database were conducted across four health service executive regions in Ireland. Results. Overall, differences in barriers, participation restriction and activity limitations experienced by people with different types of disabilities were found to be significant. Furthermore, low functioning and experience of barriers were indicators of participation restriction. Conclusions. This article has shown that elements of the ICF have been successfully operationalised in a service planning tool through the development of the MAP. This provides a more holistic view of disability and will enable the impact of service interventions to be measured over time.

  18. Analysis of interactions among the barriers to energy saving in China

    International Nuclear Information System (INIS)

    Wang Guohong; Wang Yunxia; Zhao Tao

    2008-01-01

    Since China became the second largest energy consumer and carbon dioxide emitter, the problem of energy consumption and environmental pollution has drawn the world's attention. Meanwhile, Chinese government has put high emphasis on the problem. One project of energy saving initiated by Chinese government has been put into practice. However, many difficulties need to be dealt with to meet the expected aim of social development. The objective of this article is to investigate the interactions among the major barriers which prevent the practice of energy saving in China. Obviously, a clear definition of relationships among the barriers to energy saving helps top leaders make relevant decisions to solve the problem of economic sustainability, energy security and environment pollution in the future. To date, studies specifying energy-saving barriers have often focused on analyzing these barriers separately. As a result, a holistic view in understanding the barriers to energy-saving project is lacking. Interpretive structural modeling (ISM) is utilized to summarize the critical barriers hindering the project of energy saving in China and to explain the interrelationships among them. Suggestions for energy-saving practice and future research are provided

  19. Energy efficiency barriers in commercial and industrial firms in Ukraine: An empirical analysis

    International Nuclear Information System (INIS)

    Hochman, Gal; Timilsina, Govinda R.

    2017-01-01

    Improvement in energy efficiency is one of the main options to reduce energy demand and greenhouse gas emissions. However, large-scale deployment of energy-efficient technologies is constrained by several factors. Employing a survey of 509 industrial and commercial firms throughout Ukraine and a generalized ordered logit model, we quantified the economic, behavioral, and institutional barriers that may impede the deployment of energy-efficient technologies. Our analysis shows that behavioral barriers resulted from lack of information, knowledge, and awareness are major impediments to the adoption of energy-efficient technologies in Ukraine, and that financial barriers may further impede investments in these technologies especially for small firms. This suggests that carefully targeted information provisions and energy audits will enhance Ukrainian firms' investments in energy-efficient technologies to save energy consumption, improve productivity, and reduce carbon emissions from the productive sectors. - Highlights: • Employing a survey of 509 industrial and commercial firms throughout Ukraine • A generalized ordered logit model is used in the analysis. • The paper quantifies the economic, behavioral, and institutional barriers to energy-efficient technologies. • Behavioral barriers are major impediments to the adoption of energy-efficient technologies. • Financial barriers may further impede investments in these technologies especially for small firms.

  20. Barriers to physical activity between adults with stroke and their care partners.

    Science.gov (United States)

    Zalewski, Kathryn R; Dvorak, Leah

    2011-10-01

    Healthy living includes meeting daily physical activity guidelines. This study compares daily physical activity rates and barriers to physical activity for people with stroke and their partners (spouse or significant other). Physical abilities, energy expenditure, daily steps, and barriers to physical activity are evaluated in people who have completed stroke rehabilitation and their partners. Twenty pairs of adults (mean age 69.7 years) participated. Participants with stroke were classified as sedentary, averaging 2,990 (± 2,488) steps per day. Their partners are classified as low active, averaging 6,378 (± 2,149) steps per day. For stroke survivors, physical abilities were positively correlated to daily activity rates. The number of steps walked per day was moderately correlated to 6-minute walk tests (r = 0.550, P physical abilities were not correlated to daily physical activity. People with stroke report lack of skill as a primary barrier; their partners report lack of time. The relationship between physical ability and physical activity is reinforced with this study. The impact of stroke on the family, particularly on time demands of the primary caregiver, suggests the needs of the care partner may not be adequately addressed in the rehabilitation process.

  1. Comparison of Langevin dynamics and direct energy barrier computation

    International Nuclear Information System (INIS)

    Dittrich, Rok; Schrefl, Thomas; Thiaville, Andre; Miltat, Jacques; Tsiantos, Vassilios; Fidler, Josef

    2004-01-01

    Two complementary methods to study thermal effects in micromagnetics are compared. On short time scales Langevin dynamics gives insight in the thermally activated dynamics. For longer time scales the 'nudged elastic band' method is applied. The method calculates a highly probable thermal switching path between two local energy minima of a micromagnetic system. Comparing the predicted thermal transition rates between ground states in small softmagnetic elements up to a size of 90x90x4.5 nm 3 gives good agreement of the methods

  2. The congruence energy: a contribution to nuclear masses, deformation energies and fission barriers

    International Nuclear Information System (INIS)

    Myers, W.D.; Swiatecki, W.J.

    1997-01-01

    The difference between measured binding energies and those calculated using a shell- and pairing-corrected Thomas-Fermi model can be described approximately by C(I)=-10 exp(-4.2 vertical stroke I vertical stroke) MeV, where I=(N-Z)/A. Our interpretation of this extra binding is in terms of the granularity of quantal nucleonic density distributions, which leads to a stronger interaction for a neutron and proton with congruent nodal structures of their wave functions. The predicted doubling of this congruence energy in fission is supported by an analysis of measured fission barriers and by a study of wave functions in a dividing Hill-Wheeler box potential. A semi-empirical formula for the shape-dependent congruence energy is described. (orig.)

  3. Barriers to energy efficiency in shipping: A triangulated approach to investigate the principal agent problem

    International Nuclear Information System (INIS)

    Rehmatulla, Nishatabbas; Smith, Tristan

    2015-01-01

    Energy efficiency is a key policy strategy to meet some of the challenges being faced today and to plan for a sustainable future. Numerous empirical studies in various sectors suggest that there are cost-effective measures that are available but not always implemented due to existence of barriers to energy efficiency. Several cost-effective energy efficient options (technologies for new and existing ships and operations) have also been identified for improving energy efficiency of ships. This paper is one of the first to empirically investigate barriers to energy efficiency in the shipping industry using a novel framework and multidisciplinary methods to gauge implementation of cost-effective measures, perception on barriers and observations of barriers. It draws on findings of a survey conducted of shipping companies, content analysis of shipping contracts and analysis of energy efficiency data. Initial results from these methods suggest the existence of the principal agent problem and other market failures and barriers that have also been suggested in other sectors and industries. Given this finding, policies to improve implementation of energy efficiency in shipping need to be carefully considered to improve their efficacy and avoid unintended consequences. -- Highlights: •We provide the first analysis of the principal agent problem in shipping. •We develop a framework that incorporates methodological triangulation. •Our results show the extent to which this barrier is observed and perceived. •The presence of the barrier has implications on the policy most suited to shipping

  4. Perceived barriers, benefits, and motives for physical activity: two primary-care physical activity prescription programs.

    Science.gov (United States)

    Patel, Asmita; Schofield, Grant M; Kolt, Gregory S; Keogh J, W L

    2013-01-01

    This study examined whether perceived barriers, benefits, and motives for physical activity differed based on allocation to 2 different types of primary-care activity-prescription programs (pedometer-based vs. time-based Green Prescription). Eighty participants from the Healthy Steps study completed a questionnaire that assessed their perceived barriers, benefits, and motives for physical activity. Factor analysis was carried out to identify common themes of barriers, benefits, and motives for physical activity. Factor scores were then used to explore between-groups differences for perceived barriers, benefits, and motives based on group allocation and demographic variables. No significant differences were found in factor scores based on allocation. Demographic variables relating to the existence of chronic health conditions, weight status, and older age were found to significantly influence perceived barriers, benefits, and motives for physical activity. Findings suggest that the addition of a pedometer to the standard Green Prescription does not appear to increase perceived motives or benefits or decrease perceived barriers for physical activity in low-active older adults.

  5. Physical activity barriers and motivators among high-risk employees.

    Science.gov (United States)

    Paguntalan, John C; Gregoski, Mathew

    2016-11-22

    Worksite wellness programs offer an ideal setting to target high-risk sedentary workers to improve health status. Lack of physical activity is associated with increased risk for coronary heart disease and mortality. Despite the risks, the number of sedentary workers is increasing. This study examined the perceived barriers and motivators for physical activity among employees at high-risk for coronary heart disease. A purposive sample of 24 high-risk workers participating in a wellness program in rural South Carolina were enrolled in the study. Qualitative data was obtained through semi-structured face-to-face interviews. Grounded theory was used to analyze qualitative data, and identify overarching themes. Physical limitations due to pain and weakness, lack of motivation, and lack of time emerged as the main barriers to physical activity. Family relationships were reported as the strongest motivator along with social support and potential health benefits. Findings highlight the unique experience of high-risk workers with physical activity. The findingsunderscore the need to design and implement effective interventions specifically designed to meet the needs of high-risk employees.

  6. On the economic analysis of problems in energy efficiency: Market barriers, market failures, and policy implications

    International Nuclear Information System (INIS)

    Sanstad, A.H.; Koomey, J.G.; Levine, M.D.

    1993-01-01

    In his recent paper in The Energy Journal, Ronald Sutherland argues that several so-called ''market barriers'' to energy efficiency frequently cited in the literature are not market failures in the conventional sense and are thus irrelevant for energy policy. We argue that Sutherland has inadequately analyzed the idea of market barrier and misrepresented the policy implications of microeconomics. We find that economic theory, correctly interpreted, does not provide for the categorical dismissal of market barriers. We explore important methodological issues underlying the debate over market barriers, and discuss the importance of reconciling the findings of non-economic social sciences with the economic analysis of energy demand and consumer decision-making. We also scrutinize Sutherland's attempt to apply finance theory to rationalize high implicit discount rates observed in energy-related choices, and find this use of finance theory to be inappropriate

  7. Migration energy barriers of symmetric tilt grain boundaries in body-centered cubic metal Fe

    International Nuclear Information System (INIS)

    Wu, Minghui; Gu, Jianfeng; Jin, Zhaohui

    2015-01-01

    Graphical abstract: DFT calculated migration energy barrier (left) for symmetric grain boundary in metals is an essential physical property to measure the trend of grain boundary migration, in particular, in terms of the classical homogeneous nucleation model of GB dislocation/disconnection loops (right). - Migration energy barriers of two symmetric tilt grain boundaries in body-centered cubic metal Fe are obtained via first-principles calculations in combination with the nudged elastic band methods. Although the two grain boundaries show similar grain boundary energies, the migration energy barriers are different. Based on a homogeneous nucleation theory of grain-boundary dislocation loops, the calculated energy barrier provides a measure of intrinsic grain-boundary mobility and helps to evaluate effects due to vacancy and interstitial atoms such as carbon

  8. On the economic analysis of problems in energy efficiency: Market barriers, market failures, and policy implications

    Energy Technology Data Exchange (ETDEWEB)

    Sanstad, A.H.; Koomey, J.G.; Levine, M.D.

    1993-01-01

    In his recent paper in The Energy Journal, Ronald Sutherland argues that several so-called ``market barriers`` to energy efficiency frequently cited in the literature are not market failures in the conventional sense and are thus irrelevant for energy policy. We argue that Sutherland has inadequately analyzed the idea of market barrier and misrepresented the policy implications of microeconomics. We find that economic theory, correctly interpreted, does not provide for the categorical dismissal of market barriers. We explore important methodological issues underlying the debate over market barriers, and discuss the importance of reconciling the findings of non-economic social sciences with the economic analysis of energy demand and consumer decision-making. We also scrutinize Sutherland`s attempt to apply finance theory to rationalize high implicit discount rates observed in energy-related choices, and find this use of finance theory to be inappropriate.

  9. On the economic analysis of problems in energy efficiency: Market barriers, market failures, and policy implications

    Energy Technology Data Exchange (ETDEWEB)

    Sanstad, A.H.; Koomey, J.G.; Levine, M.D.

    1993-01-01

    In his recent paper in The Energy Journal, Ronald Sutherland argues that several so-called market barriers'' to energy efficiency frequently cited in the literature are not market failures in the conventional sense and are thus irrelevant for energy policy. We argue that Sutherland has inadequately analyzed the idea of market barrier and misrepresented the policy implications of microeconomics. We find that economic theory, correctly interpreted, does not provide for the categorical dismissal of market barriers. We explore important methodological issues underlying the debate over market barriers, and discuss the importance of reconciling the findings of non-economic social sciences with the economic analysis of energy demand and consumer decision-making. We also scrutinize Sutherland's attempt to apply finance theory to rationalize high implicit discount rates observed in energy-related choices, and find this use of finance theory to be inappropriate.

  10. Symmetric fusion of heavy ions around the Coulomb barrier energy

    International Nuclear Information System (INIS)

    Royer, G.; Remaud, B.

    1983-01-01

    Using the liquid drop model, we have performed a systematic study of the symmetric fusion with a neck degree of freedom and tunnelling effects, the nuclear potential being calculated with the proximity approach. Barrier heights and positions are in very good agreement with experimental data when they are known (light-medium systems); the recent experimental data of the reactions 58 Ni + 58 Ni and 64 Ni + 64 Ni are particularly investigated. For heavier systems double-humped fusion barriers and isomeric states are predicted which strongly limit the complete fusion probability

  11. Identifying and prioritizing barriers to implementation of smart energy city projects in Europe: An empirical approach

    International Nuclear Information System (INIS)

    Mosannenzadeh, Farnaz; Di Nucci, Maria Rosaria; Vettorato, Daniele

    2017-01-01

    Successful implementation of smart energy city projects in Europe is crucial for a sustainable transition of urban energy systems and the improvement of quality of life for citizens. We aim to develop a systematic classification and analysis of the barriers hindering successful implementation of smart energy city projects. Through an empirical approach, we investigated 43 communities implementing smart and sustainable energy city projects under the Sixth and Seventh Framework Programmes of the European Union. Validated through literature review, we identified 35 barriers categorized in policy, administrative, legal, financial, market, environmental, technical, social, and information-and-awareness dimensions. We prioritized these barriers, using a novel multi-dimensional methodology that simultaneously analyses barriers based on frequency, level of impact, causal relationship among barriers, origin, and scale. The results indicate that the key barriers are lacking or fragmented political support on the long term at the policy level, and lack of good cooperation and acceptance among project partners, insufficient external financial support, lack of skilled and trained personnel, and fragmented ownership at the project level. The outcome of the research should aid policy-makers to better understand and prioritize implementation barriers to develop effective action and policy interventions towards more successful implementation of smart energy city projects. - Highlights: • A solid empirical study on the implementation of European smart energy city projects. • We found 35 barriers in nine dimensions; e.g. policy, legal, financial, and social. • We suggested a new multi-dimensional methodology to prioritize barriers. • Lacking or fragmented political support on the long term is a key barrier. • We provided insights for action for project coordinators and policy makers.

  12. Barriers to Energy Efficiency and the Uptake of Green Revolving Funds in Canadian Universities

    Science.gov (United States)

    Maiorano, John; Savan, Beth

    2015-01-01

    Purpose: The purpose of this paper is to investigate the barriers to the implementation of energy efficiency projects in Canadian universities, including access to capital, bounded rationality, hidden costs, imperfect information, risk and split incentives. Methods to address these barriers are investigated, including evaluating the efficacy of…

  13. Energy consumption and CO2 emissions of industrial process technologies. Saving potentials, barriers and instruments

    International Nuclear Information System (INIS)

    Fleiter, Tobias; Schlomann, Barbara; Eichhammer, Wolfgang

    2013-01-01

    Which contribution can the increase of energy efficiency achieve in the industry energy for the energy transition in Germany? To answer this question a model-based analysis of existing energy efficiency potentials of the energy-intensive industries is performed, which account for about 70% of the total energy demand of the industry. Based on this industry for each sector are instruments proposed for the implementation of the calculated potential and to overcome the existing barriers. [de

  14. Perceived barriers to and facilitators of physical activity in young adults with childhood-onset physical disabilities.

    Science.gov (United States)

    Buffart, Laurien M; Westendorp, Tessa; van den Berg-Emons, Rita J; Stam, Henk J; Roebroeck, Marij E

    2009-11-01

    To explore the main barriers to and facilitators of physical activity in young adults with childhood-onset physical disabilities. Qualitative study using focus groups. Sixteen persons (12 men and 4 women) aged 22.4 (standard deviation 3.4) years, of whom 50% were wheelchair-dependent, participated in the study. Eight were diagnosed with myelomeningocele, 4 with cerebral palsy, 2 with acquired brain injury and 2 with rheumatoid arthritis. Three focus group sessions of 1.5 h were conducted using a semi-structured question route to assess perceived barriers to and facilitators of physical activity. Tape recordings were transcribed verbatim and content analysed. According to the Physical Activity for People with a Physical Disability model, barriers and facilitators were subdivided into personal factors and environmental factors. Participants reported several barriers related to attitude and motivation. In addition, lack of energy, existing injury or fear of developing injuries or complications, limited physical activity facilities, and lack of information and knowledge, appeared to be barriers to physical activity. Fun and social contacts were mentioned as facilitators of engaging in physical activity, as well as improved health and fitness. Young adults with childhood-onset physical disabilities perceived various personal and environmental factors as barriers to or facilitators of physical activity. These should be taken into account when developing interventions to promote physical activity in this population.

  15. Determination of shell energies. Nuclear deformations and fission barriers

    International Nuclear Information System (INIS)

    Koura, Hiroyuki; Tachibana, Takahiro; Uno, Masahiro; Yamada, Masami.

    1996-01-01

    We have been studying a method of determining nuclear shell energies and incorporating them into a mass formula. The main feature of this method lies in estimating shell energies of deformed nuclei from spherical shell energies. We adopt three assumptions, from which the shell energy of a deformed nucleus is deduced to be a weighted sum of spherical shell energies of its neighboring nuclei. This shell energy should be called intrinsic shell energy since the average deformation energy also acts as an effective shell energy. The ground-state shell energy of a deformed nucleus and its equilibrium shape can be obtained by minimizing the sum of these two energies with respect to variation of deformation parameters. In addition, we investigate the existence of fission isomers for heavy nuclei with use of the obtained shell energies. (author)

  16. Barriers and opportunities: A review of selected successful energy-efficiency programs

    International Nuclear Information System (INIS)

    Worrell, Ernst; Price, Lynn

    2001-01-01

    In industry, barriers may exist at various points in the decision making process, and in the implementation and management of measures to improve energy efficiency. Barriers may take many forms, and are determined by the business environment and include decision-making processes, energy prices, lack of information, a lack of confidence in the information, or high transaction costs for obtaining reliable information, as well as limited capital availability. Other barriers are the ''invisibility'' of energy efficiency measures and the difficulty of quantifying the impacts, and slow diffusion of innovative technology into markets while firms typically under-invest in R and D, despite the high pay-backs. Various programs try to reduce the barriers to improve the uptake of innovative technologies. A wide array of policies has been used and tested in the industrial sector in industrialized countries, with varying success rates. We review some new approaches to industrial energy efficiency improvement in industrialized countries, focusing on voluntary agreements

  17. Examining barrier distributions and, in extension, energy derivative of probabilities for surrogate experiments

    International Nuclear Information System (INIS)

    Romain, P.; Duarte, H.; Morillon, B.

    2012-01-01

    The energy derivatives of probabilities are functions suited to a best understanding of certain mechanisms. Applied to compound nuclear reactions, they can bring information on fusion barrier distributions as originally introduced, and also, as presented here, on fission barrier distributions and heights. Extendedly, they permit to access the compound nucleus spin-parity states preferentially populated according to an entrance channel, at a given energy. (authors)

  18. Contextual barriers to lifestyle physical activity interventions in Hong Kong.

    Science.gov (United States)

    Eves, Frank F; Masters, Rich S W; McManus, Alison; Leung, Moon; Wong, Peggy; White, Mike J

    2008-05-01

    Increased lifestyle physical activity, for instance, use of active transport, is a current public health target. Active transport interventions that target stair climbing are consistently successful in English-speaking populations yet unsuccessful in Hong Kong. We report two further studies on active transport in the Hong Kong Chinese. Pedestrians on a mass transit escalator system (study 1) and in an air-conditioned shopping mall (study 2) were encouraged to take the stairs for their cardiovascular health by point-of-choice prompts. Observers coded sex, age, and walking on the mass transit system, with the additional variables of presence of children and bags coded in the shopping mall. In the first study, a 1-wk baseline was followed by 4 wk of intervention (N = 76,710) whereas in the second study (shopping mall) a 2-wk baseline was followed by a 2-wk intervention period (N = 18,257). A small but significant increase in stair climbing (+0.29%) on the mass transit system contrasted with no significant changes in the shopping mall (+0.09%). The active transport of walking on the mass transit system was reduced at higher rates of humidity and temperature, with steeper slopes for the effects of climate variables in men than in women. These studies confirm that lifestyle physical activity interventions do not have universal application. The context in which the behavior occurs (e.g., climate) may act as a barrier to active transport.

  19. Summary of Gaps and Barriers for Implementing Residential Building Energy Efficiency Strategies

    Energy Technology Data Exchange (ETDEWEB)

    2010-08-01

    This report presents the key gaps and barriers to implementing residential energy efficiency strategies in the U.S. market, as identified in sessions at the U.S. Department of Energy's Building America 2010 Residential Energy Efficiency Meeting held in Denver, Colorado, on July 20-22, 2010.

  20. The role of confined collagen geometry in decreasing nucleation energy barriers to intrafibrillar mineralization.

    Science.gov (United States)

    Kim, Doyoon; Lee, Byeongdu; Thomopoulos, Stavros; Jun, Young-Shin

    2018-03-06

    Mineralization of collagen is critical for the mechanical functions of bones and teeth. Calcium phosphate nucleation in collagenous structures follows distinctly different patterns in highly confined gap regions (nanoscale confinement) than in less confined extrafibrillar spaces (microscale confinement). Although the mechanism(s) driving these differences are still largely unknown, differences in the free energy for nucleation may explain these two mineralization behaviors. Here, we report on experimentally obtained nucleation energy barriers to intra- and extrafibrillar mineralization, using in situ X-ray scattering observations and classical nucleation theory. Polyaspartic acid, an extrafibrillar nucleation inhibitor, increases interfacial energies between nuclei and mineralization fluids. In contrast, the confined gap spaces inside collagen fibrils lower the energy barrier by reducing the reactive surface area of nuclei, decreasing the surface energy penalty. The confined gap geometry, therefore, guides the two-dimensional morphology and structure of bioapatite and changes the nucleation pathway by reducing the total energy barrier.

  1. Should we quit our jobs? Challenges, barriers and recommendations for interdisciplinary energy research

    International Nuclear Information System (INIS)

    Schuitema, Geertje; Sintov, Nicole D.

    2017-01-01

    Many plea for a better integration of social sciences in energy research, which would imply more comprehensive interdisciplinary energy research. We argue that in order to achieve this, institutional barriers and research challenges need to be recognised and addressed. We identify six challenges and barriers, and provide recommendations for working towards solutions. We conclude that to engage in interdisciplinary research implies extra costs and fewer rewards for all researchers, particularly early and mid-career academics. We propose a new conceptualisation of practices and incentive structures among academic institutions, funding agencies, and publication outlets, and urge all energy researchers to join this debate. - Highlights: • Interdisciplinary energy research currently does not reach its full potential. • Social sciences are underutilised in energy research. • Barriers and challenges need to be addressed to stimulate interdisciplinary energy research. • High costs and small rewards for interdisciplinary (early and mid-career) researchers.

  2. Vortical null orbits, repulsive barriers, energy confinement in Kerr metric

    Energy Technology Data Exchange (ETDEWEB)

    Calvani, M [Padua Univ. (Italy). Ist. di Astronomia; De Felice, F

    1978-10-01

    The complete analytical description of the null trajectories in the field of a Kerr naked singularity is given. Two peculiar phenomena are described: the existence of repulsive barriers in the r < O world and the existence of null circular bound orbits which surround the singularity in 'shells'. They distribute around the surface at r = m, which is the position of the horizon in the extreme black-hole case; this suggests that a naked singularity 'remembers' the position of the last horizon.

  3. Physical activity and exercise after stoma surgery: overcoming the barriers.

    Science.gov (United States)

    Russell, Sarah

    2017-03-09

    This article presents the results from a large nationwide survey completed in 2016 that investigated the physical health and wellbeing of people living with stomas in the UK. In particular, the survey looked at physical activity and exercise, general attitudes and opinions about exercise, whether or not advice about physical activity had been received and other general questions about parastomal hernia and quality of life. There were 2631 respondents making it one of the largest known surveys to date. The findings were concerning yet unsurprising, highlighting a trend toward inactivity after stoma surgery and a fear of exercise in general. People also seem to have poor knowledge about appropriate activities, with many suggesting that the fear of developing a parastomal hernia is a major barrier to activity. Unsurprisingly, those who have a stoma owing to cancer seem to fare worse, reporting even lower levels of physical activity and worse quality of life compared to those with other conditions. This indicates that people who have a combination of a cancer diagnosis and also a stoma may need more specific or additional support in the longer term. The most concerning finding, however, was that the majority of patients could not recall being given any advice about exercise or physical activity by their nurse or surgeon. While this survey presents some initial findings, it raises questions for further research and work. It also highlights a significantly neglected area in both research and support for stoma patients and the health professionals caring for them.

  4. Building energy efficiency for public hospitals and healthcare facilities in China: Barriers and drivers

    International Nuclear Information System (INIS)

    Wang, Tao; Li, Xiaodong; Liao, Pin-Chao; Fang, Dongping

    2016-01-01

    Maximizing energy efficiency within HHFs (hospitals and healthcare facilities) is a major challenge in the field of energy conservation. This paper studies the key barriers to the implementation of energy-efficient technologies in China's public HHFs. For this purpose, a preliminary survey was conducted at the Beijing Municipal Health Bureau in order to assess the energy conservation efforts being made at 20 public HHFs. In the survey, a list of specific barriers to energy efficiency was created and HHF staffs were asked to rank these barriers in the order of importance. The results show that the economic incentives, appropriate technology, as well as enforceable laws and regulations are insufficiently supported by the government, have become the most significant obstacles to the improvement of energy efficiency. To remedy this, policymakers should take a multipronged approach which addresses the hospitals, projects, and technical and operating procedures in order to encourage the full participation and support of all stakeholders involved. Specifically, the government should offer multilevel economic incentives and reward policies; establish practical mandatory targets for building energy efficiency; provide demonstrable best practices in terms of the project, techniques, and operating procedures; and promote awareness of the importance of property risk management. - Highlights: • We developed a checklist of building energy efficiency barriers of HHFs in China. • We took a survey to prioritize the barriers by the staff from 20 public HHFs. • Policy makers should provide multiple-level solutions to all the stakeholders. • Economic incentives, mandatory target, technique supports are critical drivers.

  5. Energy shift and conduction-to-valence band transition mediated by a time-dependent potential barrier in graphene

    Science.gov (United States)

    Chaves, Andrey; da Costa, D. R.; de Sousa, G. O.; Pereira, J. M.; Farias, G. A.

    2015-09-01

    We investigate the scattering of a wave packet describing low-energy electrons in graphene by a time-dependent finite-step potential barrier. Our results demonstrate that, after Klein tunneling through the barrier, the electron acquires an extra energy which depends on the rate of change of the barrier height with time. If this rate is negative, the electron loses energy and ends up as a valence band state after leaving the barrier, which effectively behaves as a positively charged quasiparticle.

  6. Barriers and drivers for energy efficiency: Different perspectives from an exploratory study in the Netherlands

    International Nuclear Information System (INIS)

    Cagno, Enrico; Trianni, Andrea; Abeelen, Christiaan; Worrell, Ernst; Miggiano, Federica

    2015-01-01

    Highlights: • We investigated the perception of barriers and drivers and mechanisms regulating them. • Firms agree on the most important barriers and drivers. • Firms agree on the most critical decision-making steps and actors promoting drivers. • Major external actors perceive barriers, drivers and mechanisms differently. • Success of voluntary agreements depends on the link to other policy instruments. - Abstract: Increased energy efficiency represents a crucial opportunity for European industrial sustainability, but several barriers still need to be tackled. Thus, it is crucial to understand the existing mismatches between the perception of enterprises and what the major actors promoting energy efficiency believe enterprises suffer from and need within the decision-making process. To do so, we have performed an exploratory investigation analysing a set of manufacturing enterprises participating in the Dutch voluntary agreements. The study involved the major external actors, i.e. the national energy agency, governmental and industrial organisations, to map their views on the decision-making process. Results show that enterprises agree not only on the most important barriers and drivers, but also on the mechanisms underlying them. However, even a general common understanding of the barriers is disputed when major external actors are considered, as they only agree on the primary role of economic barriers. Mismatches appear when considering how single barriers affect the decision-making process and which drivers – and actors promoting them – need to be addressed. Although voluntary agreements represent the most popular instrument on energy efficiency in the Netherlands, they do not seem to be considered by small and medium-sized enterprises as a stimulus for improving energy efficiency. Crucial for future success are the link with other policy instruments, and the degree to which the instruments trigger the right drivers and barriers at the right

  7. Physical Activity Pattern of Malaysian Preschoolers: Environment, Barriers, and Motivators for Active Play.

    Science.gov (United States)

    Lee, Shoo Thien; Wong, Jyh Eiin; Ong, Wei Wen; Ismail, Mohd Noor; Deurenberg, Paul; Poh, Bee Koon

    2016-07-01

    Children's physical activity has been correlated with child characteristics and social or physical environment. This study aimed to compare preschoolers' physical activity among various sociodemographic characteristics and to determine barriers, motivators, and environmental factors for active play. A total of 835 preschoolers were included in this analysis. Time spent on active play, quiet play, and screen time was reported by parents. Boys spent significantly more time on active play and screen time than girls. Time spent on quiet play was highest in East Coast Peninsular Malaysia and lowest in Sarawak. Some 40% of children achieved active play recommendation while 27% exceeded daily screen time recommendation. Most parents reported that their child played actively in the house area; and that the main barrier and motivator to active play were safety and child's enjoyment, respectively. These findings demonstrate that sociodemographic characteristics and environment should be considered in designing physical activity intervention programs. © 2016 APJPH.

  8. Energy Choices. Efficient Energy Use - possibilities and barriers; Vaegval Energi. Energieffektivisering - moejligheter och hinder

    Energy Technology Data Exchange (ETDEWEB)

    Jagemar, Lennart (CIT Energy Management AB, Goeteborg (Sweden)); Pettersson, Bertil (Chalmers EnergiCentrum, CEC, Chalmers Univ. of Technology, Goeteborg (Sweden))

    2009-02-15

    Sweden's total energy supply in 2006 amounted to a total of 624 TWh and was dominated by crude oil, nuclear fuels, biofuels and hydropower. Different types of losses in the system accounts for one third of the energy. The final energy consumption, i.e. delivery minus losses, was divided in the following way: industry 157 TWh, the habitat of 145 TWh (of which 19 TWh relates to Agriculture, Forestry, Fishery and other service and secondary homes) and transport of 101 TWh. For the transport sector, studies show that combinations of various efficiency measures ideally can achieve an reduction in energy use by between 60 and 75 percent. The Governmental Energy Efficiency Inquiry (EnEff - 2008) estimated that the domestic transport techno-economic efficiency potential up to 2016 is 13 TWh (mainly fuel) of the total delivered energy is 87 TWh under EnEff. The potential about 5 TWh is expected to be completed by current instruments. The study assesses that despite the increased need for transport in 2016 the sector's energy use can remain at the same level or even be reduced. Buildings have a large technical and economic energy efficiency potential. According to EnEff's assessment, the streamlining potential is 33 TWh of which 8 TWh can implemented in 2016 with today's instruments. This compares with the total delivered energy is 151 TWh under EnEff. The total energy efficiency potential for buildings by 2020 is considered to be substantially higher, about 41 TWh, and affect the use of district heating, fuel and electricity. New powerful tools must be implemented for the building sector in order to realize the potential energy efficiency measures. Industry's total energy potential is assessed to be around 13 TWh by 2016. Industry's total energy use is 155 TWh according to EnEff. Only 2 TWh can realistically be saved up to 2016 taking into account a reasonable acceptance factor. The beneficiaries of the carbon emissions trade account for about

  9. Socio-cultural barriers to the development of a sustainable energy system - the case of hydrogen

    DEFF Research Database (Denmark)

    Petersen, Lars Kjerulf; Andersen, Anne Holst

    Any transition to a more sustainable energy system, radically reducing greenhouse gas emissions, is bound to run in to a host of different barriers - technological and economic, but also socio-cultural. This will also be the case for any large-scale application of hydrogen as energy carrier......, especially if the system is going to be based on renewable energy sources. The aim of these research notes is to review and discuss major socio-cultural barriers to new forms of energy supply in general and to hydrogen specifically. Reaching sufficient reductions in greenhouse gas emissions may require more...

  10. Market failures and barriers as a basis for clean energy policies

    International Nuclear Information System (INIS)

    Brown, M.A.

    2001-01-01

    This paper provides compelling evidence that large-scale market failures and barriers prevent consumers in the United States from obtaining energy services at least cost. Assessments of numerous energy policies and programs suggest that public interventions can overcome many of these market obstacles. By articulating these barriers and reviewing the literature on ways of addressing them, this paper provides a strong justification for the policy portfolios that define the ''Scenarios for a Clean Energy Future'', a study conducted by five National Laboratories. These scenarios are described in other papers published in this special issue of Energy Policy. (author)

  11. Activation barriers for series of exothermic homologous reactions. V. Boron group diatomic species reactions

    Science.gov (United States)

    Blue, Alan S.; Belyung, David P.; Fontijn, Arthur

    1997-09-01

    Semiempirical configuration interaction (SECI) theory is used to predict activation barriers E, as defined by k(T)=ATn exp(-E/RT). Previously SECI has been applied to homologous series of oxidation reactions of s1, s2, and s2p1 metal atoms. Here it is extended to oxidation reactions of diatomic molecules containing one s2p1 atom. E values are calculated for the reactions of BH, BF, BCl, AlF, AlCl, AlBr, GaF, GaI, InCl, InBr, InI, TlF, TlCl, TlBr, and TlI with O2, CO2, SO2, or N2O. These values correlate with the sums of the ionization potentials and Σ-Π promotion energies of the former minus the electron affinities of the latter. In the earlier work n was chosen somewhat arbitrarily, which affected the absolute values of E. Here it is shown that examination of available experimental and theoretical results allows determination of the best values of n. Using this approach yields n=1.9 for the present series. For the seven reactions which have been studied experimentally, the average deviation of the SECI activation barrier prediction from experiment is 4.0 kJ mol-1. Energy barriers are calculated for another 52 reactions.

  12. A novel method for calculating the energy barriers for carbon diffusion in ferrite under heterogeneous stress

    Science.gov (United States)

    Tchitchekova, Deyana S.; Morthomas, Julien; Ribeiro, Fabienne; Ducher, Roland; Perez, Michel

    2014-07-01

    A novel method for accurate and efficient evaluation of the change in energy barriers for carbon diffusion in ferrite under heterogeneous stress is introduced. This method, called Linear Combination of Stress States, is based on the knowledge of the effects of simple stresses (uniaxial or shear) on these diffusion barriers. Then, it is assumed that the change in energy barriers under a complex stress can be expressed as a linear combination of these already known simple stress effects. The modifications of energy barriers by either uniaxial traction/compression and shear stress are determined by means of atomistic simulations with the Climbing Image-Nudge Elastic Band method and are stored as a set of functions. The results of this method are compared to the predictions of anisotropic elasticity theory. It is shown that, linear anisotropic elasticity fails to predict the correct energy barrier variation with stress (especially with shear stress) whereas the proposed method provides correct energy barrier variation for stresses up to ˜3 GPa. This study provides a basis for the development of multiscale models of diffusion under non-uniform stress.

  13. A novel method for calculating the energy barriers for carbon diffusion in ferrite under heterogeneous stress

    International Nuclear Information System (INIS)

    Tchitchekova, Deyana S.; Morthomas, Julien; Perez, Michel; Ribeiro, Fabienne; Ducher, Roland

    2014-01-01

    A novel method for accurate and efficient evaluation of the change in energy barriers for carbon diffusion in ferrite under heterogeneous stress is introduced. This method, called Linear Combination of Stress States, is based on the knowledge of the effects of simple stresses (uniaxial or shear) on these diffusion barriers. Then, it is assumed that the change in energy barriers under a complex stress can be expressed as a linear combination of these already known simple stress effects. The modifications of energy barriers by either uniaxial traction/compression and shear stress are determined by means of atomistic simulations with the Climbing Image-Nudge Elastic Band method and are stored as a set of functions. The results of this method are compared to the predictions of anisotropic elasticity theory. It is shown that, linear anisotropic elasticity fails to predict the correct energy barrier variation with stress (especially with shear stress) whereas the proposed method provides correct energy barrier variation for stresses up to ∼3 GPa. This study provides a basis for the development of multiscale models of diffusion under non-uniform stress

  14. A novel method for calculating the energy barriers for carbon diffusion in ferrite under heterogeneous stress

    Energy Technology Data Exchange (ETDEWEB)

    Tchitchekova, Deyana S. [IRSN, PSN, SEMIA, LPTM, Saint-Paul-Lez-Durance (France); Univ. Lyon, INSA Lyon, MATEIS, UMR CNRS 5510, Villeurbanne (France); Morthomas, Julien; Perez, Michel [Univ. Lyon, INSA Lyon, MATEIS, UMR CNRS 5510, Villeurbanne (France); Ribeiro, Fabienne [IRSN, PSN, SEMIA, LPTM, Saint-Paul-Lez-Durance (France); Ducher, Roland [IRSN, PSN, SAG, LETR, Saint-Paul-Lez-Durance (France)

    2014-07-21

    A novel method for accurate and efficient evaluation of the change in energy barriers for carbon diffusion in ferrite under heterogeneous stress is introduced. This method, called Linear Combination of Stress States, is based on the knowledge of the effects of simple stresses (uniaxial or shear) on these diffusion barriers. Then, it is assumed that the change in energy barriers under a complex stress can be expressed as a linear combination of these already known simple stress effects. The modifications of energy barriers by either uniaxial traction/compression and shear stress are determined by means of atomistic simulations with the Climbing Image-Nudge Elastic Band method and are stored as a set of functions. The results of this method are compared to the predictions of anisotropic elasticity theory. It is shown that, linear anisotropic elasticity fails to predict the correct energy barrier variation with stress (especially with shear stress) whereas the proposed method provides correct energy barrier variation for stresses up to ∼3 GPa. This study provides a basis for the development of multiscale models of diffusion under non-uniform stress.

  15. Motivators and Barriers to Engaging in Healthy Eating and Physical Activity.

    Science.gov (United States)

    Ashton, Lee M; Hutchesson, Melinda J; Rollo, Megan E; Morgan, Philip J; Collins, Clare E

    2017-03-01

    Many Australian young men (18-25 years) fail to meet recommendations in national dietary or physical activity (PA) guidelines. However, there is a lack of understanding of their perspectives on PA and diet to inform intervention design. This study examined young men's motivators and barriers to healthy eating and PA, along with differences by demographic and behavioral factors. A cross-sectional online survey was completed by 282 men aged 18 to 25 years in Australia. Results identified the most common motivators for healthy eating included improving health (63.5%), body image (52.3%), and increasing energy (32.1%). Motivators for PA included improving body image (44.6%), fitness (44.2%), and health (41.0%). Common barriers to healthy eating were access to unhealthy foods (61.1%), time to cook/prepare healthy foods (55.0%), and motivation to cook healthy foods (50.7%). Barriers for PA included motivation (66.3%), time (57.8%), and cost of equipment/facilities (33.3%). Significant differences ( p motivators to healthy eating and/or PA were identified for BMI category, marital status, PA level, alcohol intake, and stress levels. Significant differences were identified for barriers to healthy eating and/or PA by BMI, PA level, stress, and fruit and vegetable intake, assessed using Pearson's chi-square test. Findings suggest that promotion of benefits related to health, appearance/body image, increased energy and fitness, and addressing key barriers including motivation, time, financial restraints, and accessibility of unhealthy foods, could engage young men in improving lifestyle behaviors. Differences by demographic and behavioral factors suggest development of tailored programs to address diversity among young men may be required.

  16. The prevalence of barriers for Colombian college students engaging in physical activity.

    Science.gov (United States)

    Ramírez-Vélez, Robinson; Tordecilla-Sanders, Alejandra; Laverde, David; Hernández-Novoa, Juan Gilberto; Ríos, Marcelo; Rubio, Fernando; Correa-Bautista, Jorge Enrique; Martinez-Torres, Javier

    2014-09-18

    To investigate the prevalence of barriers and their association with Colombia college students engaging in PA. A total of 5,663 students (3,348 male) from three cities in Colombia. In fall 2013, students voluntarily completed a demographic questionnaire, Barriers to Being Active Quiz. Logistic regression analysis of each barrier (adjusted for confusion variables: gender, age and BMI) was used for verifying such association. The most prevalent barriers in overweight individuals were "fear of injury" (87.0%), "lack of skill" (79.8%) and "lack of resources" (64.3%). The group of females revealed a protective association regarding "lack of time" (OR=0.53: 0.47-0.60 95%CI), "social influence" (OR=0.67: 0.60-0.75 95%CI), "lack of energy" (OR=0.54: 0.49-0.61 95%CI), "lack of willpower" (OR=0.57: 0.51- 0.64 95%CI), "lack of skill" (OR=0.76: 0.66-0.87 95%CI) and "lack of resources" (OR=0.79: 0.71-0.89 95%CI). Such observation also appeared in the 20- to 23-yearold age group concerning "social influence" (OR=0.83: 0.74-0.94 95%CI) and in those aged over 23-years-old (OR=0.86: 0.74-0.99 95%CI) regarding "lack of energy". A significant prevalence was found regarding self-perception of barriers leading to students ceasing to engage in PA. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  17. Diffusion of renewable energy technologies - barriers and stakeholders' perspectives

    DEFF Research Database (Denmark)

    Reddy, S.; Painuly, Jyoti P.

    2004-01-01

    State, India, as a case study, the paper develops a systematic classification of barriers to the adoption of RETs (economic, technological, market and institutional) and ranking them based on the perceptions of various stakeholders. The results provide evidence of how the consumers receive RET...... information and make decisions using their limited analytical capabilities. The analysis is used to enhance the knowledge by introducing ideas based on behavioural theory. Not only do these ideas help understanding the consumer perspective, they also help develop policy interventions. The aim is to define...

  18. The role of cooperatives in overcoming the barriers to adoption of renewable energy

    International Nuclear Information System (INIS)

    Viardot, Eric

    2013-01-01

    Recently, cooperatives have been created to promote the use of renewable energy (RE) most notably in Canada, the US, UK, Denmark or Germany. In order to develop the adoption of RE, the cooperatives have to seek to influence the behaviour of their members so that they switch from the use of traditional fossil energy to RE. This paper examines the various barriers to adoption of RE and the way cooperatives are circumventing those obstacles in order to develop the use of RE. This study surveyed a sample of 9 cooperatives from countries where governments are subsidizing the use of RE. The paper identifies a set of specific barriers to the adoption of RE by consumers. It also reveals that cooperatives effectively contribute to the uptake of RE with community-based social marketing initiatives that are lowering those barriers successfully. Those initiatives are related to educational communication, low prices, local offers with complementary services, and cooperative distribution. The paper put forwards a framework for the assessment of how each of those initiatives contributes to the diminishing of each of the barriers to adoption of RE. - Highlights: • We examine the barriers to adoption of renewable energy by RE cooperatives. • We have identified the main significant barriers to adoption of RE by consumers. • Cooperatives apply community-based marketing initiatives to ease the uptake of RE. • We evaluate how each marketing initiatives diminish the barriers to adoption of RE

  19. Implementation of renewable energy technologies - Opportunities and barriers. Ghana country study

    Energy Technology Data Exchange (ETDEWEB)

    Edjekumhene, I.; Atakora, S.B.; Atta-Konadu, R.; Brew-Hammond, A. [Kumasi Inst. og Technology and Environment (Ghana)

    2001-07-01

    This report presents the experience of Ghana in the development, utilisation and promotion of Renewable Energy Technologies (RETs). The report gives a general overview of the state of RETs, describes past/existing institutional, regulatory and policy framework, identifies key barriers to and opportunities for RETs, and recommends directional changes needed to remove barriers and promote wide-scale adoption of RETs in Ghana. A total of eight RETs - biomass-fired dryers, sawdust stoves, sawdust briquette, biogas, solar crop dryer, solar water heater, solar water pump and small hydro power - are covered in the report. Analyses of barriers to the eight RETs are carried out using a framework approach that categorises barriers into socio-technical, economic and crosscutting barriers. Financial analyses, as opposed to economic analyses, have been carried out for all the selected RETs. The report also incorporates stake holders' perspectives and views on barriers and how they can be removed. Ghana is endowed with several renewable energy resources like solar radiation, small hydro, biomass, and wind. Exploitation of Ghana's renewable energy resources has been carried out under two main policy regimes - PND Law 62 (1983) and the Energy Sector Development Programme (ESDP). Several measures and instruments have been employed in the implementation of renewable energy policies. The main measures used are research and development, information and eduction, and some normative measures (like the passing of PNDC Law 62 and the Energy Commission Law). Some economic instruments, such as subsidies, taxes, pricing, financing and duty waiver/reduction, have been used as well but only to a limited extent. The effective development, implementation and dissemination of all the RETs studied are hampered by several barriers, which can be grouped into three main categories - Socio-technical barriers, economic barriers and crosscutting barriers. Socio-technical barriers refer to

  20. Implementation of renewable energy technologies - Opportunities and barriers. Ghana country study

    Energy Technology Data Exchange (ETDEWEB)

    Edjekumhene, I; Atakora, S B; Atta-Konadu, R; Brew-Hammond, A [Kumasi Inst. og Technology and Environment (Ghana)

    2001-07-01

    This report presents the experience of Ghana in the development, utilisation and promotion of Renewable Energy Technologies (RETs). The report gives a general overview of the state of RETs, describes past/existing institutional, regulatory and policy framework, identifies key barriers to and opportunities for RETs, and recommends directional changes needed to remove barriers and promote wide-scale adoption of RETs in Ghana. A total of eight RETs - biomass-fired dryers, sawdust stoves, sawdust briquette, biogas, solar crop dryer, solar water heater, solar water pump and small hydro power - are covered in the report. Analyses of barriers to the eight RETs are carried out using a framework approach that categorises barriers into socio-technical, economic and crosscutting barriers. Financial analyses, as opposed to economic analyses, have been carried out for all the selected RETs. The report also incorporates stake holders' perspectives and views on barriers and how they can be removed. Ghana is endowed with several renewable energy resources like solar radiation, small hydro, biomass, and wind. Exploitation of Ghana's renewable energy resources has been carried out under two main policy regimes - PND Law 62 (1983) and the Energy Sector Development Programme (ESDP). Several measures and instruments have been employed in the implementation of renewable energy policies. The main measures used are research and development, information and eduction, and some normative measures (like the passing of PNDC Law 62 and the Energy Commission Law). Some economic instruments, such as subsidies, taxes, pricing, financing and duty waiver/reduction, have been used as well but only to a limited extent. The effective development, implementation and dissemination of all the RETs studied are hampered by several barriers, which can be grouped into three main categories - Socio-technical barriers, economic barriers and crosscutting barriers. Socio-technical barriers refer to resource

  1. Quantitative structure-activation barrier relationship modeling for Diels-Alder ligations utilizing quantum chemical structural descriptors.

    Science.gov (United States)

    Nandi, Sisir; Monesi, Alessandro; Drgan, Viktor; Merzel, Franci; Novič, Marjana

    2013-10-30

    In the present study, we show the correlation of quantum chemical structural descriptors with the activation barriers of the Diels-Alder ligations. A set of 72 non-catalysed Diels-Alder reactions were subjected to quantitative structure-activation barrier relationship (QSABR) under the framework of theoretical quantum chemical descriptors calculated solely from the structures of diene and dienophile reactants. Experimental activation barrier data were obtained from literature. Descriptors were computed using Hartree-Fock theory using 6-31G(d) basis set as implemented in Gaussian 09 software. Variable selection and model development were carried out by stepwise multiple linear regression methodology. Predictive performance of the quantitative structure-activation barrier relationship (QSABR) model was assessed by training and test set concept and by calculating leave-one-out cross-validated Q2 and predictive R2 values. The QSABR model can explain and predict 86.5% and 80% of the variances, respectively, in the activation energy barrier training data. Alternatively, a neural network model based on back propagation of errors was developed to assess the nonlinearity of the sought correlations between theoretical descriptors and experimental reaction barriers. A reasonable predictability for the activation barrier of the test set reactions was obtained, which enabled an exploration and interpretation of the significant variables responsible for Diels-Alder interaction between dienes and dienophiles. Thus, studies in the direction of QSABR modelling that provide efficient and fast prediction of activation barriers of the Diels-Alder reactions turn out to be a meaningful alternative to transition state theory based computation.

  2. Methane activation using Kr and Xe in a dielectric barrier discharge reactor

    International Nuclear Information System (INIS)

    Jo, Sungkwon; Lee, Dae Hoon; Kim, Kwan-Tae; Kang, Woo Seok; Song, Young-Hoon

    2014-01-01

    Methane has interested many researchers as a possible new energy source, but the high stability of methane causes a bottleneck in methane activation, limiting its practical utilization. To determine how to effectively activate methane using non-thermal plasma, the conversion of methane is measured in a planar-type dielectric barrier discharge reactor using three different noble gases—Ar, Kr, and Xe—as additives. In addition to the methane conversion results at various applied voltages, the discharge characteristics such as electron temperature and electron density were calculated through zero-dimensional calculations. Moreover, the threshold energies of excitation and ionization were used to distinguish the dominant particle for activating methane between electrons, excited atoms, and ionized atoms. From the experiments and calculations, the selection of the additive noble gas is found to affect not only the conversion of methane but also the selectivity of product gases even under similar electron temperature and electron density conditions

  3. Energy Model of Neuron Activation.

    Science.gov (United States)

    Romanyshyn, Yuriy; Smerdov, Andriy; Petrytska, Svitlana

    2017-02-01

    On the basis of the neurophysiological strength-duration (amplitude-duration) curve of neuron activation (which relates the threshold amplitude of a rectangular current pulse of neuron activation to the pulse duration), as well as with the use of activation energy constraint (the threshold curve corresponds to the energy threshold of neuron activation by a rectangular current pulse), an energy model of neuron activation by a single current pulse has been constructed. The constructed model of activation, which determines its spectral properties, is a bandpass filter. Under the condition of minimum-phase feature of the neuron activation model, on the basis of Hilbert transform, the possibilities of phase-frequency response calculation from its amplitude-frequency response have been considered. Approximation to the amplitude-frequency response by the response of the Butterworth filter of the first order, as well as obtaining the pulse response corresponding to this approximation, give us the possibility of analyzing the efficiency of activating current pulses of various shapes, including analysis in accordance with the energy constraint.

  4. Internationalization as a strategy to overcome industry barriers-An assessment of the marine energy industry

    Energy Technology Data Exchange (ETDEWEB)

    Lovdal, Nicolai, E-mail: nicolai.lovdal@iot.ntnu.n [Industrial Economics and Technology Management, Norwegian University of Science and Technology, 7491 Trondheim (Norway); Neumann, Frank, E-mail: frank@wave-energy-centre.or [Wave Energy Centre, Av. Manuel Maia, 36, r/c Dto., 1000-201 Lisboa (Portugal)

    2011-03-15

    Research on conditions to develop new innovations within emerging renewable energy industries is often done with a national focus. However, recent research on international entrepreneurship has revealed that firms operate on international levels very early in their life time. Thus, based on former research on international entrepreneurship and case examples, we build the propositions that firms in the marine energy industry use internationalization as a strategy to overcome industry barriers. Our primary source of data is a unique dataset from a global survey of all the companies in the marine energy industry who are aiming to commercialize a wave or tidal energy device. This paper is organized in two steps: first we identified the most challenging industry barriers perceived by companies. Second we use these to form propositions which we assess through empirical data. The two most challenging barriers perceived by the companies are need for capital and need for supportive political schemes. Our findings reveal that internationalization certainly is a common strategy to access capital and attractive support schemes in foreign countries. The early internationalization has implications for researchers, managers and policy makers. - Research highlights: {yields} Industry barriers identified as access to capital and supportive political schemes. {yields} International entrepreneurship is used to overcome industry barriers. {yields} Start-ups in emerging energy industries 'shop' national support schemes. {yields} Future research to provide policy advice should adapt to the international reality. {yields} Research based on a worldwide survey of wave and tidal energy device developers.

  5. Internationalization as a strategy to overcome industry barriers-An assessment of the marine energy industry

    International Nuclear Information System (INIS)

    Lovdal, Nicolai; Neumann, Frank

    2011-01-01

    Research on conditions to develop new innovations within emerging renewable energy industries is often done with a national focus. However, recent research on international entrepreneurship has revealed that firms operate on international levels very early in their life time. Thus, based on former research on international entrepreneurship and case examples, we build the propositions that firms in the marine energy industry use internationalization as a strategy to overcome industry barriers. Our primary source of data is a unique dataset from a global survey of all the companies in the marine energy industry who are aiming to commercialize a wave or tidal energy device. This paper is organized in two steps: first we identified the most challenging industry barriers perceived by companies. Second we use these to form propositions which we assess through empirical data. The two most challenging barriers perceived by the companies are need for capital and need for supportive political schemes. Our findings reveal that internationalization certainly is a common strategy to access capital and attractive support schemes in foreign countries. The early internationalization has implications for researchers, managers and policy makers. - Research highlights: → Industry barriers identified as access to capital and supportive political schemes. → International entrepreneurship is used to overcome industry barriers. → Start-ups in emerging energy industries 'shop' national support schemes. → Future research to provide policy advice should adapt to the international reality. → Research based on a worldwide survey of wave and tidal energy device developers.

  6. Barriers to Leisure-Time Physical Activities in Individuals with Spinal Cord Injury.

    Science.gov (United States)

    Hwang, Eric J; Groves, Mary D; Sanchez, Jacqueline N; Hudson, Cassandra E; Jao, Rachel G; Kroll, Meghan E

    2016-07-01

    This study investigated the personal, environmental, and activity barriers to leisure-time physical activities (LTPAs) among individuals with spinal cord injury (SCI). A survey instrument was administered to 85 participants with SCI. Personal barriers to LTPAs included issues involving motivation, pain, scheduling, and financial resources. Environmental barriers marked the issues regarding availability and accessibility to specialized programs, activities, and professional services. Activity barriers included limitations in equipment, training, and personal skills required by the selected activities. Significant negative correlations were found between these barriers and the levels of physical activity and satisfaction with physical activity. While working with clients with SCI, occupational therapists should identify those LTPA barriers and possible solutions in order to establish individualized action plans for enhancing participation in LTPAs.

  7. Manure and energy crops for biogas production. Status and barriers

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, H.B.; Nielsen, A.M.; Murto, M.; Christensson, K.; Rintala, J.; Svensson, M.; Seppaelae, M.; Paavola, T.; Angelidaki, I.; Kaparaju, P.L.

    2008-07-01

    This study has evaluated the development of biogas technology in three Nordic countries and analysed the effects of using nine model energy crops as supplement to manure feedstocks in biogas plants. The study compares the global warming impacts and the energy balance for the nine crops used for heat and power production. The energy balances and impacts on greenhouse gases of the studied crops differ between the countries. In Sweden and Denmark, the same crops turned out to be the most promising in terms of energy yield and impact on greenhouse gases. In general, the same crops that score high in terms of energy yield also score high in reducing the amount of greenhouse gases. Based on the examined parameters, it can be concluded that the most promising crops are Jerusalem artichoke, beets, maize, and, in Finland, reed canary grass as well. (au)

  8. Why do kids eat healthful food? Perceived benefits of and barriers to healthful eating and physical activity among children and adolescents.

    Science.gov (United States)

    O'dea, Jennifer A

    2003-04-01

    The goal was to have children and adolescents identify and rank the major perceived benefits of and barriers to healthful eating and physical activity and to suggest strategies for overcoming barriers. Semistructured, in-depth focus groups were undertaken using standardized questions and prompts. Students in grades 2 through 11(ages 7 through 17; N=213) from 34 randomly selected schools participated in 38 focus groups. Major benefits of healthful eating included improvements to cognitive and physical performance, fitness, endurance, psychological benefits, physical sensation (feeling good physically), and production of energy. Barriers included convenience, taste, and social factors. Benefits of physical activity included social benefits, enhancement of psychological status, physical sensation, and sports performance. Barriers included a preference for indoor activities, lack of energy and motivation, time constraints, and social factors. Suggested strategies for overcoming barriers included support from parents and school staff, better planning, time management, self-motivation, education, restructuring the physical environment, and greater variety of physical activities.

  9. Implementation of renewable energy technology - Opportunities and barriers. Summary of country studies

    Energy Technology Data Exchange (ETDEWEB)

    Painuly, J.P.; Fenhann, J.V.

    2002-07-01

    The project was launched to identify barriers to the implementation of renewable energy technologies (RETs) and explore measures to overcome the identified barriers. National institutions in Egypt, Ghana and Zimbabwe carried out the country studies based on the basic methodological framework provided by the UNEP Centre. The objectives of the project included strengthening institutional capacity for analysis and implementation of RET projects in the participating countries and bring out experiences on RETs barriers and removal measures for dissemination so that others can benefit from the knowledge so gained. An important highlight of the studies was involvement of stake holders in the process of identification of barriers and measures to remove them. A preliminary identification of relevant RETs for their countries was done by the country teams in the initial stage of the project. After that, national workshops involving various stake holders were held between July and September 1999 to discuss the RETs and barriers to their implementation. Based on the discussions, a few important RETs were identified for more detailed study. PV systems for rural electrification, solar water heating systems and large-scale biogas system were identified and analysed for barriers in the Egypt country study. Economic, information and policy barriers were identified as major barriers for these technologies. Solar water pumps, biogas and small hydro were the focus of study in Ghana. In this case also, economic, information and policy barriers were found to be the important barriers for the selected technologies. In the case of Zimbabwe, focus was on identification of primary and secondary barriers to RETs dissemination. The primary barriers included lack of capacity to develop proposals, lack of information for policy making and framework for information dissemination. The study concluded that the secondary barriers as seen and experienced by the stake holders are due to primary

  10. Barriers to energy efficiency: International case studies on successful barrier removal

    NARCIS (Netherlands)

    Worrell, E.

    2011-01-01

    Industry uses nearly 40 percent of worldwide energy to produce materials and products consumed by us all on a daily basis. In the process it contributes almost 37 percent of global greenhouse gas emissions (GHG). Globally, and in most countries, CO2 accounts for more than 90 percent of CO2-eq GHG

  11. Numerical evaluation of energy barriers and magnetic relaxation in interacting nanostructured magnetic systems

    International Nuclear Information System (INIS)

    Chubykalo-Fesenko, Oksana A.; Chantrell, Roy W.

    2004-01-01

    We discuss a model to quantify long-time thermally induced magnetization reversal in magnetic systems with distributed properties. Two algorithms, based on kinetic and Metropolis Monte Carlo are introduced. While the former requires the constant recalculation of all energy barriers and is useful when the interactions are weak, the latter uses the Metropolis Monte Carlo to estimate the magnetization trajectory and, consequently, only the most probable transition rates are evaluated. The ridge optimization method is used to evaluate the energy barriers in a multidimensional energy landscape. The algorithms are applied to a granular system modeled by means of Voronoi polyhedra and having random in-plane anisotropy

  12. Barriers to the adoption of energy-conserving technologies in the textile industry

    Energy Technology Data Exchange (ETDEWEB)

    Evans, A.R.; Zussman, S.K.

    1979-09-01

    An overview of the textile industry and a discussion of energy-conserving technologies currently available at the pilot-demonstration stage are presented. Existing and potential barriers to the adoption of these technologies in the textile industry identified are: economic; technical acceptance; conflict between commitments of capital for compliance with environmental and health regulations and for investment in energy conservation measures; and a lack of information and technical expertise. Possible measures to eliminate barriers to the implementation of energy-conserving technologies are discussed. (MCW)

  13. Potential and barrier study. Energy efficiency of Norwegian homes; Potensial- og barrierestudie. Energieffektivisering av norske boliger

    Energy Technology Data Exchange (ETDEWEB)

    Mjoenes, Christian; Pettersen, Folke Vogn Haug; Kristoffersen, Bjoerge Sandberg; Birkeland, Bjoern Mangor; Essen, Jan von; Haarberg; Karl Johan

    2012-01-15

    On behalf of Enova SF, Prognosesenteret AS and Entelligens AS carried out a potential and barrier study of energy efficiency of the Norwegian housing stock. The study made use of newer and known studies of the Norwegian housing stock, known and documented barriers to energy efficiency, and new and extensive studies of several topics which have only been partially or never explored before. Through unique analysis and a case-based approach, it revealed a real energy efficiency potential in Norwegian homes with known technology and revealed representativeness, relevance, strength and extent of the barriers that prevent that one can realize most of the technical energy efficiency potential in the Norwegian housing stock. (eb)

  14. Factors Affecting Energy Barriers for Pyramidal Inversion in Amines and Phosphines: A Computational Chemistry Lab Exercise

    Science.gov (United States)

    Montgomery, Craig D.

    2013-01-01

    An undergraduate exercise in computational chemistry that investigates the energy barrier for pyramidal inversion of amines and phosphines is presented. Semiempirical calculations (PM3) of the ground-state and transition-state energies for NR[superscript 1]R[superscript 2]R[superscript 3] and PR[superscript 1]R[superscript 2]R[superscript 3] allow…

  15. Dealing with barriers to energy efficiency and SMEs: Some empirical evidences

    International Nuclear Information System (INIS)

    Trianni, A.; Cagno, E.

    2012-01-01

    This paper aims at providing an identification and an analysis of the most relevant barriers to energy efficiency that limit a widespread implementation of the Best Available Technologies and Practices (BAT/Ps) through the investigation of 128 non-energy intensive manufacturing Small and Medium-sized Enterprises (SMEs) in Northern Italy. The study, starting from the existing literature, performs an investigation of the operational difficulties occurring when it has been decided to undertake the process of investing resources in energy efficiency interventions. The most perceived barriers have been analyzed with respect to several important characteristics (among others, sector and firm’s size). This examination shows also that very much attention should be paid to avoid bundling together SMEs of different sizes and sectors, since different behaviors with respect to the perception of the barriers can be observed. The analysis of the sample presents some interesting trends considering the perception of the barriers with respect to previous experience of the enterprises on energy efficiency. The paper also explores, through a preliminary analysis, the correlations among questions in order to understand the dynamics and the possible effects of a given barrier with respect to others. Several suggestions for future research in this important area have been provided. -- Highlights: ► Evidences of different behaviors with respect to energy efficiency among sectors and firm’s size (within SMEs). ► Importance, for energy efficiency barriers, of avoid bundling SMEs as a whole. ► Preliminary investigation of relationships between barriers in order to understand the dynamics.

  16. The diffusion of solar energy use in HK: What are the barriers?

    International Nuclear Information System (INIS)

    Zhang Xiaoling; Shen Liyin; Chan, Sum Yee

    2012-01-01

    The world is facing the severe challenges of energy depletion and carbon dioxide (CO 2 ) emissions, and solar energy is considered to be a promising source of renewable energy and effective solution. However, the application of solar energy is limited in practice due to various barriers. Based on data collected from a survey of practice, this paper identifies the key barriers to the deployment of solar photovoltaic (PV) energy systems in Hong Kong. These include “high initial and repair cost”, “long payback period”, “inadequate installation space and service infrastructure”, “lack of participation of stakeholders/community in energy policy” and “lack of incentives by legislation and regulation”. Recommendations for addressing these barriers are proposed. For example, the high cost of solar PV energy systems can be reduced by the development and mass production of low-cost fabrication technologies and high performance PV technologies. Solar thermal applications should be encouraged as they are much more economical than solar PVs. It is also recommended that the Hong Kong Government adopt strategies to encourage a greater use of solar energy systems. The results from this study not only provide useful information for the Government, the private sector and consumers in Hong Kong but are also likely to apply equally to other similar regions around the world. - Highlights: ► The Hong Kong Government needs to adopt various strategies to encourage the solar energy system application. ► This paper identifies the key barriers to the diffusion of solar energy systems from a questionnaire survey and case study in Hong Kong. ► The barriers highlighted from the questionnaire survey include “high initial and repair cost”, “long payback period”, “inadequate installation space and service infrastructure”, “lack of stakeholder/community participation in energy choices” and “legal and regulation constraints”.

  17. Implementation of renewable energy technologies - Opportunities and barriers. Egypt country study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The project used case studies of renewable energy implementation projects to analyse the reasons for success or failure of specific projects or technologies. In particular the study aimed to identify possibilities for 'removing' the main barriers and thus 'promoting' increased implementation of (RETs), and to 'generalise' the experiences from the case studies and produce results that can be disseminated and utilized further in a planned second phase. The specific objectives for Egypt Country Study were: 1) To determine, on the basis of analysis of the past experience, the barriers against implementation of RETs in Egypt, and to identify the favourable conditions and actions required for such implementation. 2) To apply the knowledge gained and results of the analysis of past projects for a detailed analysis of barriers to a chosen set of potential RETs implementation projects with view to success. 3) To identify specific RET projects for implementation including necessary actions to overcome identified barriers. The case study revealed that; for Domestic Solar Water Heating (DSWH) the main barriers are; the economic barriers followed by the awareness / information barriers, then the Technical and Institution barriers. For the PV rural electrification, the most important barriers are; the economic and financial barriers, the awareness and information barriers then the technical barriers. For the large-scale biogas systems, the main barriers are the institution and capacity, economic, policy and awareness / information respectively. According to the project results the main actions that could be taken to overcome the barriers and make use of the available opportunities are: Economic / Financial: 1) Creation of new financial schemes for the RETs applications components and systems. 2) Reducing the taxes and duties for the components and / or materials needed for Renewable Energy (RE) systems. 3) More government-supported market incentives

  18. Implementation of renewable energy technologies - Opportunities and barriers. Egypt country study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The project used case studies of renewable energy implementation projects to analyse the reasons for success or failure of specific projects or technologies. In particular the study aimed to identify possibilities for 'removing' the main barriers and thus 'promoting' increased implementation of (RETs), and to 'generalise' the experiences from the case studies and produce results that can be disseminated and utilized further in a planned second phase. The specific objectives for Egypt Country Study were: 1) To determine, on the basis of analysis of the past experience, the barriers against implementation of RETs in Egypt, and to identify the favourable conditions and actions required for such implementation. 2) To apply the knowledge gained and results of the analysis of past projects for a detailed analysis of barriers to a chosen set of potential RETs implementation projects with view to success. 3) To identify specific RET projects for implementation including necessary actions to overcome identified barriers. The case study revealed that; for Domestic Solar Water Heating (DSWH) the main barriers are; the economic barriers followed by the awareness / information barriers, then the Technical and Institution barriers. For the PV rural electrification, the most important barriers are; the economic and financial barriers, the awareness and information barriers then the technical barriers. For the large-scale biogas systems, the main barriers are the institution and capacity, economic, policy and awareness / information respectively. According to the project results the main actions that could be taken to overcome the barriers and make use of the available opportunities are: Economic / Financial: 1) Creation of new financial schemes for the RETs applications components and systems. 2) Reducing the taxes and duties for the components and / or materials needed for Renewable Energy (RE) systems. 3) More government-supported market incentives to encourage further

  19. Correlation between diffusion barriers and alloying energy in binary alloys

    DEFF Research Database (Denmark)

    Vej-Hansen, Ulrik Grønbjerg; Rossmeisl, Jan; Stephens, Ifan

    2016-01-01

    In this paper, we explore the notion that a negative alloying energy may act as a descriptor for long term stability of Pt-alloys as cathode catalysts in low temperature fuel cells.......In this paper, we explore the notion that a negative alloying energy may act as a descriptor for long term stability of Pt-alloys as cathode catalysts in low temperature fuel cells....

  20. Renewable energy policy options for Abu Dhabi: Drivers and barriers

    International Nuclear Information System (INIS)

    Mezher, Toufic; Dawelbait, Gihan; Abbas, Zeina

    2012-01-01

    Climate change and fossil fuel depletion are the main drivers for the recent focus on Renewable Energy (RE) resources. However, since the high cost of RE technologies is the main obstacle facing the diffusion of RE power generation, economic and political intervention is inevitable. In the United Arab Emirates (UAE) population and economic growth are the main causes of a sharp increase of energy demand. Two key related factors highlight the need to establish a RE sector: first the UAE has one of the highest carbon footprint in the world and second, the rate of depletion of its main energy generation resource – fossil fuel. In this study, we present a review of overall policies in sixty-one countries, focusing on their efforts to adopt RE resources in the power sector, and on their implementation of fundamental policies implemented. Furthermore, we investigate the applicability to Abu Dhabi UAE of the main RE policies implemented worldwide. As a result of our analysis, we recommend the implementation of a mixed policy of Feed-in-Tariff (FIT) and the Quota system for RE electricity generation in order for the UAE to meet its 7% target by 2020. - Highlights: ► Comprehensive review of renewable energy policy mechanisms. ► Summarizes the renewable energy policy adoptions, targets, and installed capacity in many countries. ► Gives recommendations on renewable energy policy options for Abu Dhabi, an oil rich country.

  1. Active control of internal transport barrier and confinement database in JT-60U reversed shear plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Yoshiteru; Takizuka, Tomonori; Shirai, Hiroshi; Fujita, Takaaki; Kamada, Yutaka; Ide, Shunsuke; Fukuda, Takeshi; Koide, Yoshihiko [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-07-01

    Active control of internal transport barrier (ITB) and confinement properties of plasma with ITB have been studied in reversed shear plasmas. Modifications of the radial electric field (E{sub r}) profile by changing the combination of tangential neutral beams can control the ITB strength, where the contribution to E{sub r} from the toroidal rotation plays an important role. The ITB confinement database of reversed shear plasmas has been constructed. Stored energy is strongly correlated with poloidal magnetic field at the ITB foot. (author)

  2. Predictors of perceived barriers to physical activity in the general adult population: a cross-sectional study.

    Science.gov (United States)

    Herazo-Beltrán, Yaneth; Pinillos, Yisel; Vidarte, José; Crissien, Estela; Suarez, Damaris; García, Rafael

    The perception of personal barriers to physical activity varies according to the sociodemographic characteristics of individuals. To determine the predictors of the perception of barriers to physical activity in the adult population. A cross-sectional study with 1066 adult women and 1036 adult men. The sociodemographic variables (age, gender, marital status, socioeconomic level, level of education), the perception of barriers that do not allow performance of physical activity (i.e. lack of time, social support, energy, motivation, skill, resources, and fear of injury during practice); and the level of physical activity through the International Physical Activity Questionnaire in its short-form version were evaluated. Individuals from low socioeconomic level (1 and 2) have higher risks of perceiving barriers such as lack of motivation [OR 1.76 (95% CI (1.4-2.1))] and lack of resources [OR 1.37 (95% CI (1.1-1.6))]; individuals with partners did not perceive the lack of social support [OR 0.29 (95% CI (0.2-0.4))] and lack of motivation [OR 0.54 (95% CI (0.4-0.7))] as barriers to physical activity. Individuals with low schooling perceived lack of social support [OR 3.81 (95% CI (3-4.7))], lack of resources [OR 2.78 (95% CI (2.2-3.3))], and fear of injury [OR 2.70 (95% CI (2.2-3.3))] as barrier to physical activity. Factors such as socioeconomic level, marital status, level of education, and self-perception of health are predictors of barriers to physical activity. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

  3. International energy-promotion-activities

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    Comprehensive promotion of energy and environmental measures are demanded in order to realize improvement in energy demand/supply structures in developing countries where increase in energy demand is anticipated. To achieve this goal, technical transfer related to energy saving technologies and clean coal as well as international energy promotion activities are implemented in China and Indonesia since fiscal 1993. In the field of energy saving, model operations are performed to improve efficiency in such energy consuming fields as steel making, power generation, and oil refining, in addition to cooperation in structuring databases and establishing master plans. In the clean coal field, model operations are conducted to reduce environmental load in coal utilizing areas, in addition to cooperation in establishing master plans for coal utilization. This paper describes feasibility studies on environmentally harmonious coal utilization systems in developing countries, assistance to introduction thereof, and joint verification operations. To rationalize international energy usage, basic surveys on energy utilization efficiency improvement and model operations are carried out mainly in the Asia-Pacific countries.

  4. Addressing Social and Institutional Barriers for Wind Energy Installations

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, L; Gonzalez, R; Varela, M [Ciemat. Madrid (Spain); Ramirez, I; Vicente, F [Consejeria de Medio Ambiente, Agricultura y Agua. Comunidad Autonoma de Murcia (Spain)

    2000-07-01

    This project has been jointly financed by the European Commission and developed within the Programme Thermie-B. The main tasks to carried out are: Revision of institutional and legal framework. The revision of institutional and legal framework of different participating countries, i. e. their comparison with the rest of the countries with a relevant role in the field of wind energy. Opinion poll carried out on the wind energy. By means of this means, one wants to test public opinion with respect to wind energy. So for such purpose, there are interviews carried out in the municipalities with wind parks, as well as in those where these are in the process of being installed or the project is in its due course. Simulation of wind parks installation. The Wind Park Wandered software tool is a Design and Visualisation tool developed by CINAR, which allows the preview of potential wind parks, evaluating their visual and audio impact. Production and distribution of information on wind energy. For such purpose, we can include the present publication with which one could summarise the main aspects associated with wind energy from its origin, the study of energy source (wind), and the machines that make use of it or the most relevant social and environmental contexts. Organizing informative seminars on the design possibilities of wind parks. At these seminar, one could assess the present wind energy situation in the European context and in each one of the participating countries. And possibilities of presenting WPW software as a design tool for wind parks. (Author) 12 refs.

  5. Addressing Social and Institutional Barriers for Wind Energy Installations

    International Nuclear Information System (INIS)

    Ramirez, L.; Gonzalez, R.; Varela, M.; Saez, R.; Ramirez, I.; Vicente, F.

    2000-01-01

    This project has been jointly financed by the European Commission and developed within the Programme Thermie- B. The main tasks to carried out are: Revision of institutional and legal framework. The revision of institutional and legal framework of different participating countries, i.e. their comparison with the rest of the countries with a relevant role in the field of wind energy. Opinion poli carried out on the wind energy. By means of this means, one wants to test public opinion with respect to wind energy. So for such purpose, there are interviews carried out in the municipalities with wind parks, as well as in those where these are in the process of being installed or the project is in its due course. Simulation of wind parks installation. The Wind Park Wandered software tool is a Design and Visualisation tool developed by CINAR, which allows the preview of potential wind parks, evaluating their visual and audio impact. Production and distribution of information on wind energy. For such purpose, we can include the present publication with which one could summarise the main aspects associated with wind energy from its origin, the study of energy source (wind), and the machines that make use of it or the most relevant social and environmental contexts. Organising informative seminars on the design possibilities of wind parks. At these seminars, one could assess the present wind energy situation in the European context and in each one of the participating countries. And possibilities of presenting WPW software as a design tool for wind parks. (Author) 12 refs

  6. Are the barriers for physical activity practice equal for all peripheral artery disease patients?

    Science.gov (United States)

    Cavalcante, Bruno R; Farah, Breno Q; dos A Barbosa, João Paulo; Cucato, Gabriel Grizzo; da Rocha Chehuen, Marcel; da Silva Santana, Fábio; Wolosker, Nelson; de Moraes Forjaz, Cláudia Lúcia; Ritti-Dias, Raphael M

    2015-02-01

    To investigate barriers to physical activity related to the sociodemographic comorbidities and clinical variables of patients with intermittent claudication. Cross-sectional study. Ambulatory care. The medical histories of patients (N=145) aged ≥50 years with intermittent claudication were examined. Not applicable. Sociodemographic data (sex, race, level of education, socioeconomic status, marital status), comorbidities (overweight, hypertension, dyslipidemia, diabetes, currently smoking, heart disease), and clinical variables (initial claudication distance, total walking distance, ankle-brachial index). Information on personal and environmental barriers was obtained by questionnaire. Low economic status was most associated with "being afraid of falling" (odd ratios [OR]=2.22; 95% confidence interval [CI], 1.08-4.54). Low education level was most associated with "lack of street pedestrian crossing" (OR=3.34; 95% CI, 1.48-7.52). Diabetes was associated with lack of energy (OR=3.38; 95% CI, 1.68-6.79) and other medical conditions (eg, arthritis, angina) (OR=3.44; 95% CI, 1.65-7.16). Ankle brachial index was associated with "some difficulty in getting to a place where physical activity can be performed" (OR=2.75; 95% CI, 1.22-6.21). Walking capacity was strongly associated with barriers relating to leg pain (OR=7.39; 95% CI, 1.66-32.88). Older patients, those with a low education level, patients with diabetes, low ankle brachial index, and those with a lower walking capacity are more likely to experience barriers to physical activity. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Barriers and Facilitators of Breasteeding for Primiparous Active Duty Military Mothers: A Qualitative Study

    National Research Council Canada - National Science Library

    Bristow, Kristine

    1999-01-01

    .... This descriptive study describes the barriers and facilitators of breastfeeding for primiparous active duty military mothers, from their perspective, using a Husserlian phenomenological approach...

  8. Energy Saving by Firms. Decision-Making, Barriers and Policies

    Energy Technology Data Exchange (ETDEWEB)

    De Groot, H.L.F.; Verhoef, E.T.; Nijkamp, P. [Vrije Universiteit Amsterdam (Netherlands)

    1999-04-01

    Promoting investments in energy saving technologies is an important means for achieving environmental goals. Unfortunately, the empirical evidence on success conditions of policies is scarce. Based on a survey among Dutch firms, this paper sets out to identify the factors that determine the investment behaviour of firms, their attitude towards various types of energy policy, and their responsiveness to changes in environmental policy in the Netherlands. On the basis of discrete choice models, this paper aims to investigate empirically whether (and how) these strategic features vary over firm characteristics and over sectors. 15 refs.

  9. Energy saving by firms. Decision-making, barriers and policies

    Energy Technology Data Exchange (ETDEWEB)

    De Groot, H.L.F.; Verhoef, E.T.; Nijkamp, P. [Department of Spatial Economics and Tinbergen Institute, Vrije Universiteit, De Boelelaan 1105, 1081 HV Amsterdam (Netherlands)

    2001-11-01

    Promoting investments in energy-saving technologies is an important means for achieving environmental goals. Empirical evidence on success conditions of associated policies, however, is scarce. Based on a survey among Dutch firms, this paper sets out to identify the factors that determine the investment behaviour of firms, their attitude towards various types of energy policy, and their responsiveness to changes in environmental policy in the Netherlands. On the basis of discrete choice models, this paper aims to investigate empirically, whether (and how) these strategic features vary over firm characteristics and over sectors.

  10. Energy saving by firms. Decision-making, barriers and policies

    International Nuclear Information System (INIS)

    De Groot, H.L.F.; Verhoef, E.T.; Nijkamp, P.

    2001-01-01

    Promoting investments in energy-saving technologies is an important means for achieving environmental goals. Empirical evidence on success conditions of associated policies, however, is scarce. Based on a survey among Dutch firms, this paper sets out to identify the factors that determine the investment behaviour of firms, their attitude towards various types of energy policy, and their responsiveness to changes in environmental policy in the Netherlands. On the basis of discrete choice models, this paper aims to investigate empirically, whether (and how) these strategic features vary over firm characteristics and over sectors

  11. Review of Renewable Energy Technologies in Zambian Households: Capacities and Barriers Affecting Successful Deployment

    Directory of Open Access Journals (Sweden)

    Priscilla Kachapulula-Mudenda

    2018-05-01

    Full Text Available Modern renewable energy has been hailed as one of the prerequisites for fostering green growth and the achievement of sustainable development. Despite efforts to promote the use of renewable energy in households, its adoption has remained fairly low, hence the need for an inquiry into household capabilities needed for the acquisition and adoption of renewable energy technologies. This paper reviews the requisite capacities of households for the adoption of renewable energy services and expounds on some of the barriers hampering renewable energy among households. It takes a desk research approach to analyse the capacities which should be possessed by Zambian households and possible barriers constraining the widespread deployment of renewable energy technologies. The findings reveal that there is a need for a broader, multidimensional understanding of access to renewable energy in order for deployment to be effective. Barriers to the successful adoption of clean energy technologies include underserved populations, policy inadequacies; an underexploited renewable energy sector and heavy reliance on a service-challenged hydro-power utility. Since most of the aforementioned challenges are institutional in nature, the paper concludes with a recommendation of a baseline assessment to understand knowledge, perceptions, attitudes and drivers for renewable energy technology adoption among households.

  12. Barriers for recess physical activity: a gender specific qualitative focus group exploration

    DEFF Research Database (Denmark)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper

    Background: Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender...... (53 boys) from fourth grade, with a mean age of 10.4 years. The focus groups included an open group discussion, go-along group interviews, and a gender segregated post-it note activity. A content analysis of the post-it notes was used to prioritize the children´s perceived barriers. This was verified...... barriers, there were both inter- and intra-gender differences in the children´s perceptions of these barriers. Weather was a barrier for all children, apart from the most active boys. Conflicts were perceived as a barrier particularly for those boys who played ballgames. Girls said they would like to have...

  13. Are barriers to physical activity similar for adults with and without abnormal glucose metabolism?

    Science.gov (United States)

    Hume, Clare; Dunstan, David; Salmon, Jo; Healy, Genevieve; Andrianopoulos, Nick; Owen, Neville

    2010-01-01

    The purpose of this study was to examine perceived barriers to physical activity among adults with and without abnormal glucose metabolism (AGM), and whether barriers varied according to physical activity status. The 1999 to 2000 Australian Diabetes, Obesity, and Lifestyle Study (AusDiab) was a population-based cross-sectional study among adults aged > or =25 years. AGM was identified through an oral glucose tolerance test. The previous week's physical activity and individual, social, and environmental barriers to physical activity were self-reported. Logistic regression analyses examined differences in barriers to physical activity between those with and without AGM, and for those with and without AGM who did and did not meet the minimum recommendation of 150 minutes/week of moderate-to-vigorous intensity physical activity. Of the 7088 participants (47.5 +/- 12.7 years; 46% male), 18.5% had AGM. Approximately 47.5% of those with AGM met the physical activity recommendation, compared to 54.7% of those without AGM (P barriers to physical activity included lack of time, other priorities, and being tired. Following adjustment for sociodemographic and behavioral factors, there were few differences in barriers to physical activity between those with and without AGM, even after stratifying according to physical activity. Adults with AGM report similar barriers to physical activity, as do those without AGM. Programs for those with AGM can therefore focus on the known generic adult-reported barriers to physical activity.

  14. Potential and barrier study. Energy efficiency in Norwegian vocational buildings; Potensial- og barrierestudie. Energieffektivisering i norske yrkesbygg

    Energy Technology Data Exchange (ETDEWEB)

    Boehn, Trond Ivar; Palm, Linn Therese; Bakken, Line; Nossum, Aase; Jordell, Hanne

    2012-07-01

    On behalf of Enova SF, Multiconsult AS and Analyse og Strategi AS conducted an analysis to identify potential and barriers related to commercial buildings energy performance. The aim of this study was to determine what is the potential for energy efficiency for Norwegian vocational buildings that distinguishes between theoretical, technical, financial and real potential. Technical potential is the percentage of the theoretical potential that is technically feasible. Economic potential is the proportion of technical potential that is economically profitable to implement. Economic potential varies with the energy price. Build a small part of the total potential in 2020. In the calculation of the real potential is taken into account induced potential in terms of that, each year, a percentage actually implementing energy conservation measures (energy efficiency ratio 2%), a percentage rehabilitating / upgrading existing buildings (rehab rate 1.5%), and that a proportion of new buildings built better than regulatory requirements (rate 10%). In real potential for energy efficiency is the proportion of the economic potential that is not natural triggered but which is limited by various barriers. In real potential also varies with energy price. Respondents in our study is particularly concerned with the economic barriers, and least concerned the technical barriers. Attitudes and knowledge barriers are also very important. Lack of knowledge the effects and benefits of energy efficiency means that negative attitudes persist and that myths about the lack of profitability continues to exist. Many believe this is due to lack the knowledge and can be the cause of other types of barriers such as economic barriers. It has been analyzed which part of the real potential bounded by the barriers, and which type of institutions in society that can reduce these barriers with various categories of instrument. Main barriers for existing buildings practical barriers, economic barriers and

  15. Overheating risk barriers to energy renovations of single family houses

    DEFF Research Database (Denmark)

    Psomas, Theofanis Ch.; Heiselberg, Per Kvols; Duer, Karsten

    2016-01-01

    Highlights •Energy renovations of houses in moderate climates increase overheating risk. •Critical measures are the floor insulation and the improvement of the airtightness. •Decrease of the g value of windows diminishes the intensity and the period of it. •Static method of assessment shows highe...

  16. Heavy-ion reactions at energies near the Coulomb barrier

    International Nuclear Information System (INIS)

    Satchler, G.R.

    1991-01-01

    The title covers a very broad area of both experimental and theoretical studies. The common characteristic of heavy-ion collisions at these energies, compared to what is usually seen at higher energies, is the important interplay between different reaction channels or internal degrees of freedom. The couplings between the various channels can result in important multistep contributions to a given channel. These often have to be treated explicitly, for example by solving the appropriate set of coupled equations. In contrast, at higher energies the effects of these couplings frequently can be represented in a simple, average way, as is done when one introduces an imaginary part to the optical potential for elastic scattering. At first, it might be thought that the possible importance of multistep transitions would be a strong disadvantage of working at these energies. However, although the analysis of the data becomes more complicate, the study of these terms and their interferences can be a rich source of information. In particular, it can tell us, indirectly, something about transitions between two excited states. Overviews of some of these phenomena have been presented elsewhere; here I have selected two topics as representative. Even then I cannot go into much detail, so perhaps this paper is best regarded as providing some references as the stating point for a literature search exclamation point

  17. Energy saving by firms: decision making, barriers and policies

    NARCIS (Netherlands)

    de Groot, H.L.F.; Verhoef, E.T.; Nijkamp, P.

    2001-01-01

    Promoting investments in energy-saving technologies is an important means for achieving environmental goals. Empirical evidence on success conditions of associated policies, however, is scarce. Based on a survey among Dutch firms, this paper sets out to identify the factors that determine the

  18. Perceived barriers to physical activity among Nigerian stroke survivors

    African Journals Online (AJOL)

    The four most reported common barriers among stroke survivors were access to exercise facilities (95.0 %), being embarrassed to exercise (94.2%), economic cost demands of exercise (94.2 %) and notion that people in exercise clothes look funny (94.2%) respectively. There were no significant differences found in barriers ...

  19. Technical Barriers, Gaps, and Opportunities Related to Home Energy Upgrade Market Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, M. V. A.

    2011-11-01

    This report outlines the technical barriers, gaps, and opportunities that arise in executing home energy upgrade market delivery approaches, as identified through research conducted by the U.S. Department of Energy's Building America program. The objective of this report is to outline the technical1 barriers, gaps, and opportunities that arise in executing home energy upgrade market delivery approaches, as identified through research conducted by the U.S. Department of Energy's (DOE) Building America program. This information will be used to provide guidance for new research necessary to enable the success of the approaches. Investigation for this report was conducted via publications related to home energy upgrade market delivery approaches, and a series of interviews with subject matter experts (contractors, consultants, program managers, manufacturers, trade organization representatives, and real estate agents). These experts specified technical barriers and gaps, and offered suggestions for how the technical community might address them. The potential benefits of home energy upgrades are many and varied: reduced energy use and costs; improved comfort, durability, and safety; increased property value; and job creation. Nevertheless, home energy upgrades do not comprise a large part of the overall home improvement market. Residential energy efficiency is the most complex climate intervention option to deliver because the market failures are many and transaction costs are high (Climate Change Capital 2009). The key reasons that energy efficiency investment is not being delivered are: (1) The opportunity is highly fragmented; and (2) The energy efficiency assets are nonstatus, low-visibility investments that are not properly valued. There are significant barriers to mobilizing the investment in home energy upgrades, including the 'hassle factor' (the time and effort required to identify and secure improvement works), access to financing, and the

  20. E4 - Energy efficient elevators and escalators. Barriers to and strategies for promoting energy-efficient lift and escalator technologies

    Energy Technology Data Exchange (ETDEWEB)

    Duetschke, Elisabeth; Hirzel, Simon

    2010-02-25

    According to prior findings of the E4 project, considerable savings potential exists both for lifts and escalators that could be realized if appropriate technology is implemented. However, energy-efficient technology is slowly diffusing the market - a phenomenon that could be explained by barriers present in the market. A barrier is defined as a mechanism that inhibits a decision or behavior that appears to be both energy-efficient and economically efficient and thereby prevents investment in energy-efficient technologies. This document has two aims. First, it will identify influential barriers in the European lift and escalator market. This analysis is based on the literature as well as a study including interviews as well as group discussions with relevant stakeholders. Second, strategies and measures to overcome the barriers identified in the first step are outlined. Major barriers to the penetration of energy-efficient technologies identified in this paper include a lack of monitoring energy consumption of installations and a lack of awareness of as well as knowledge about energy-efficient technology. Thus, installations and components are usually chosen without a (comprehensive) assessment of their energy consumption and without considering life-cycle approaches. On top of this, split incentives are a regularly occurring barrier. Various stakeholders are influential in the decisionmaking process about an installation or its components. However, those who will later pay for the energy consumption often are not involved in this process. Moreover, it is important to keep in mind that the number of new lifts and escalators installed each year is relatively low compared to the existing stock. Thus, it is very important to discuss enhancement of energy efficiency also for the existing stock. Based on our analyses, several recommendations are developed in this paper that could contribute to a market transformation in the lift and escalator market. First of all, a

  1. Perceived Benefits, Facilitators, Disadvantages, and Barriers for Physical Activity Amongst South Asian Adolescents in India and Canada.

    Science.gov (United States)

    Rajaraman, Divya; Correa, Natasha; Punthakee, Zubin; Lear, Scott A; Jayachitra, Krishnaswamy G; Vaz, Mario; Swaminathan, Sumathi

    2015-07-01

    The purpose of this study was to understand perceived benefits, facilitators, disadvantages, and barriers for physical activity among South Asian adolescents in India and Canada. Thirteen focus group discussions with South Asian (origin) adolescent boys and girls of different nutritional status and socioeconomic status in rural and urban India and urban Canada. Across the groups, fitness and 'energy' were perceived to be major benefits of physical activity. In India, better academic performance was highlighted, while health benefits were well detailed in Canadian groups. In all settings, friends, family, and teachers were perceived as facilitators of as well as barriers to physical activity. Lack of a safe space to play was a major concern for urban adolescents, while academic pressures and preference for other sedentary recreational activities were common barriers across all groups. Girls were less likely than boys to be interested in physical activity, with girls' participation in India further limited by societal restrictions. The study suggests key areas for promotion of physical activity among South Asian adolescents: balance between academic pressure and opportunities for physical activity, especially in India; urban planning for a built environment conducive to physical activity; and gender-sensitive programming to promote girls' activity which also addresses culture-specific barriers.

  2. Removing barriers to women entrepreneurs’ engagement in decentralized sustainable energy solutions for the poor

    Directory of Open Access Journals (Sweden)

    Yannick Glemarec

    2016-01-01

    Full Text Available  Rapidly falling renewable technology costs and new business models mean that decentralized energy solutions hold great promise to accelerate universal sustainable energy access. Across developing countries, women are typically the primary household energy managers. Close to their customers, women entrepreneurs have the potential to lower customer acquisition and servicing costs and drive these new decentralized solutions. However, they remain under-represented in the industry. This paper attempts to understand the root causes of this gender gap. It formulates the research hypothesis that market transformation policies intended to reduce investment risks to accelerate energy access may not benefit men and women entrepreneurs equally because of the existing structural barriers that women face. To test this hypothesis, the paper conducts a gender sensitive investment barrier and risk analysis, overlaid onto an existing gender neutral taxonomy of investment barriers and risks for decentralized sustainable energy solutions. A key finding is that for women entrepreneurs, existing structural impediments to gender equality translate into additional investment barriers as well as increased likelihood of occurrence and severity of the financial impact of generic investment risks. The paper offers an illustrative theory of change to facilitate a dialogue on the specific interventions needed to address these gender differentiated risks locally. It concludes that market transformation efforts for universal sustainable energy access must include targeted policy measures to ensure equal benefits to men and women entrepreneurs, and optimize the use of public resources to catalyze private investment and reduce poverty.

  3. High energy lithium-oxygen batteries - Transport barriers and thermodynamics

    KAUST Repository

    Das, Shyamal K.

    2012-01-01

    We show that it is possible to achieve higher energy density lithium-oxygen batteries by simultaneously lowering the discharge overpotential and increasing the discharge capacity via thermodynamic variables alone. By assessing the relative effects of temperature and pressure on the cell discharge profiles, we characterize and diagnose the critical roles played by multiple dynamic processes that have hindered implementation of the lithium-oxygen battery. © 2012 The Royal Society of Chemistry.

  4. Barriers for recess physical activity: a gender specific qualitative focus group exploration.

    Science.gov (United States)

    Pawlowski, Charlotte Skau; Tjørnhøj-Thomsen, Tine; Schipperijn, Jasper; Troelsen, Jens

    2014-06-23

    Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender differences in children's perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. Data were collected through 17 focus groups (at 17 different schools) with in total 111 children (53 boys) from fourth grade, with a mean age of 10.4 years. The focus groups included an open group discussion, go-along group interviews, and a gender segregated post-it note activity. A content analysis of the post-it notes was used to rank the children's perceived barriers. This was verified by a thematic analysis of transcripts from the open discussions and go-along interviews. The most frequently identified barriers for both boys and girls were weather, conflicts, lack of space, lack of play facilities and a newly-found barrier, use of electronic devices. While boys and girls identified the same barriers, there were both inter- and intra-gender differences in the perception of these barriers. Weather was a barrier for all children, apart from the most active boys. Conflicts were perceived as a barrier particularly by those boys who played ballgames. Girls said they would like to have more secluded areas added to the school playground, even in large schoolyards where lack of space was not a barrier. This aligned with girls' requests for more "hanging-out" facilities, whereas boys primarily wanted activity promoting facilities. Based on the results from this study, we recommend promoting recess physical activity through a combination of actions, addressing barriers within the natural, social, physical and organizational environment.

  5. Barriers and Potential Solutions for Energy Renovation of Buildings in Denmark

    DEFF Research Database (Denmark)

    Meyer, Niels I; Mathiesen, Brian vad; Hvelplund, Frede

    2014-01-01

    the supply and demand side for heat, electricity and transport. Implementing such Smart Energy Systems requires integrated strategic energy planning on the national and local level. With the fundamental changes in the energy supply technologies expected during the coming years, it is important to synchronize...... investments in energy conservation measures with investments in the supply side, in order to avoid overinvestment in supply systems and thus to minimize the total costs of the transformation to Smart Energy Systems. This paper highlights some of the most important barriers for renovation of existing buildings...

  6. Does weight status influence perceptions of physical activity barriers among African-American women?

    Science.gov (United States)

    Genkinger, Jeanine M; Jehn, Megan L; Sapun, Marcella; Mabry, Iris; Young, Deborah Rohm

    2006-01-01

    Many African-American women fail to participate in regular physical activity. Weight status may influence physical activity barriers. This study examined the frequency and type of barriers. Participants in this study were enrolled in Project EXE-L (Exercising Ladies Excel), a six-month, church-based, randomized trial of moderate-intensity physical activity based in Baltimore city and county in Maryland. Participants were composed of African-American women who attended one of the participating churches, had friends who were church members, or who lived in neighborhoods surrounding one of the churches. Individuals who were between the ages of 25 and 70 years, were not regularly physically active (defined as not engaging in moderate-intensity activity more than three times per week), and were able to participate in moderate-intensity activity met eligibility criteria to participate in the trial. Barriers to physical activity were evaluated with the Steinhardt/Dishman Barriers for Habitual Physical Activity Scale at baseline. One hundred twenty women were classified as normal weight (body mass index [BMI]: or = 30 kg/m2). Obese participants were more likely to report "lack of motivation" as a barrier compared with normal-weight participants (63% vs 31%). Normal-weight and overweight participants were more likely to report no barriers compared with the obese (31%, 0%, 5%, respectively, P<.05). Barriers for African-American women may vary by BMI status. By defining these unique barriers, effective physical activity interventions can be developed.

  7. Analyzing Barriers to Energy Conservation in Residences and Offices: The Rewire Program at the University of Toronto

    Science.gov (United States)

    Stokes, Leah C.; Mildenberger, Matto; Savan, Beth; Kolenda, Brian

    2012-01-01

    Conducting a barriers analysis is an important first step when designing proenvironmental behavior change interventions. Yet, detailed information on common barriers to energy conservation campaigns remains unavailable. Using a pair of original surveys, we leverage the theory of planned behavior to report on the most important barriers for…

  8. Perceived Barriers to and Facilitators of Physical Activity in Recipients of Solid Organ Transplantation, a Qualitative Study.

    Directory of Open Access Journals (Sweden)

    Edwin J van Adrichem

    Full Text Available Sufficient physical activity is important for solid organ transplant recipients (heart, lung, liver, kidney. However, recipients do not meet the recommended amount or required type of physical activity. The perceived barriers to and facilitators of physical activity in this population are largely unknown.Semi-structured in depth interviews were conducted with solid organ transplant recipients in order to explore experienced barriers and facilitators. Qualitative methodology with thematic line-by-line analysis was used for analysis, and derived themes were classified into personal and environmental factors.The most important indicated barriers were physical limitations, insufficient energy level, fear, and comorbidities. The most frequently mentioned facilitators included motivation, coping, consequences of (inactivity, routine/habit, goals/goal priority, and responsibility for the transplanted organ. Neutral factors acting as a barrier or facilitator were self-efficacy and expertise of personnel. A comparison of barriers and facilitators between transplant recipient groups yielded no overt differences.Several personal and environmental factors were indicated that should be considered in intervention development to increase physical activity behavior in solid organ transplant recipients.

  9. Market barriers to energy efficiency: A critical reappraisal of the rationale for public policies to promote energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Golove, W.H.; Eto, J.H. [Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

    1996-03-01

    This report reviews current perspectives on market barriers to energy efficiency. Ratepayer-funded utility energy-efficiency programs are likely to change in scope, size, and nature as the deregulation process proceeds; the authors research focuses on understanding to what extent some form of future intervention may be warranted and how they might judge the success of particular interventions, especially those funded by ratepayers. They find that challenges to the existence of market barriers have, for the most part, failed to provide a testable alternative explanation for evidence suggesting that there is a substantial ``efficiency gap`` between a consumer`s actual investments in energy efficiency and those that appear to be in the consumer`s own interest. They then suggest that differences of opinion about the appropriateness of public policies stem not from disputes about whether market barriers exist, but from different perceptions of the magnitude of the barriers, and the efficacy and (possibly unintended) consequences of policies designed to overcome them. They conclude that there are compelling justifications for future energy-efficiency policies. Nevertheless, in order to succeed, they must be based on a sound understanding of the market problems they seek to correct and a realistic assessment of their likely efficacy. This understanding can only emerge from detailed investigations of the current operation of individual markets.

  10. Barriers to Energy Efficiency in Swedish Non-Energy-Intensive Micro- and Small-Sized Enterprises—A Case Study of a Local Energy Program

    Directory of Open Access Journals (Sweden)

    Fredrik Backman

    2017-01-01

    Full Text Available Improved energy efficiency has become a strategic issue and represents a priority for European competitiveness. Countries adopt various energy policies on local and national levels where energy audit programs are the most common energy end-use efficiency policy for industrial small- and medium-sized enterprises (SMEs. However, studies indicate that cost-efficient energy conservation measures are not always implemented, which can be explained by the existence of barriers to energy efficiency. This paper investigates how Swedish municipalities can support local micro- and small-sized enterprises with improved energy efficiency and the existence of different barriers to the implementation of energy efficiency. Relating this empirical case study to the theoretical barriers outlined in the text, this study found that the major explanatory factors related to non-implementation of cost-effective energy efficiency measures among micro- and small-sized industrial enterprises were bounded rationality (lack of time and/or other priorities, split incentives (having other priorities for capital investments, and imperfect information (slim organization and lack of technical skill. This study also found that information in the form of a report was the main thing that companies gained from working on the project “Energy-Driven Business”. Notably, the study involved companies that had participated in a local energy program and, still, companies face major barriers inhibiting implementation, indicating a need to further study other alternative policy models and how knowledge transfer can be improved.

  11. Removal of atrazine in water by combination of activated carbon and dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Vanraes, Patrick, E-mail: patrick.vanraes@ugent.be [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium); Willems, Gert; Nikiforov, Anton [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium); Surmont, Pieter; Lynen, Frederic [Separation Science Group, Department of Organic Chemistry, Ghent University, Krijgslaan 281 S4-bis, 9000 Gent (Belgium); Vandamme, Jeroen; Van Durme, Jim [Research Group Molecular Odor Chemistry, Department of Microbial and Molecular Systems (M2S), KU Leuven, Technology Campus, Gebroeders De Smetstraat 1, 9000 Gent (Belgium); Verheust, Yannick P.; Van Hulle, Stijn W.H.; Dumoulin, Ann [Department of Industrial Biological Sciences, Ghent University, Graaf Karel de Goedelaan 5, 8500 Kortrijk (Belgium); Leys, Christophe [Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, 9000 Gent (Belgium)

    2015-12-15

    Highlights: • Increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. • Chlorine containing oxidation by-products of first and later generations are detected with HPLC–MS analysis, in agreement with literature. • Desorption analysis shows lower atrazine concentration and higher by-product concentration on activated carbon textile after plasma treatment. • Comparison with plasma reactors described in literature for atrazine decomposition confirms relatively high energy efficiency of our reactor. - Abstract: Efficiency of modern wastewater treatment plants to remove or decompose persistent contaminants in low concentration is often insufficient to meet the demands imposed by governmental laws. Novel, efficient and cheap methods are required to address this global issue. We developed a new type of plasma reactor, in which atrazine decomposition by atmospheric dielectric barrier discharge (DBD) in dry air is combined with micropollutant adsorption on activated carbon textile and with extra bubbling of generated ozone. Investigation of reaction kinetics and by-product analysis shows that increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. By-products of first and later generations are detected with HPLC–MS analysis in water and adsorbed on the activated carbon textile. Our reactor is compared in energy efficiency with reactors described in literature, showing that combination of plasma discharge with pollutant adsorption and ozone recycling is attractive for future applications of water treatment.

  12. Removal of atrazine in water by combination of activated carbon and dielectric barrier discharge

    International Nuclear Information System (INIS)

    Vanraes, Patrick; Willems, Gert; Nikiforov, Anton; Surmont, Pieter; Lynen, Frederic; Vandamme, Jeroen; Van Durme, Jim; Verheust, Yannick P.; Van Hulle, Stijn W.H.; Dumoulin, Ann; Leys, Christophe

    2015-01-01

    Highlights: • Increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. • Chlorine containing oxidation by-products of first and later generations are detected with HPLC–MS analysis, in agreement with literature. • Desorption analysis shows lower atrazine concentration and higher by-product concentration on activated carbon textile after plasma treatment. • Comparison with plasma reactors described in literature for atrazine decomposition confirms relatively high energy efficiency of our reactor. - Abstract: Efficiency of modern wastewater treatment plants to remove or decompose persistent contaminants in low concentration is often insufficient to meet the demands imposed by governmental laws. Novel, efficient and cheap methods are required to address this global issue. We developed a new type of plasma reactor, in which atrazine decomposition by atmospheric dielectric barrier discharge (DBD) in dry air is combined with micropollutant adsorption on activated carbon textile and with extra bubbling of generated ozone. Investigation of reaction kinetics and by-product analysis shows that increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. By-products of first and later generations are detected with HPLC–MS analysis in water and adsorbed on the activated carbon textile. Our reactor is compared in energy efficiency with reactors described in literature, showing that combination of plasma discharge with pollutant adsorption and ozone recycling is attractive for future applications of water treatment.

  13. Control strategies for active noise barriers using near-field error sensing

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    In this paper active noise control strategies for noise barriers are presented which are based on the use of sensors near the noise barrier. Virtual error signals are derived from these near-field sensor signals such that reductions of the far-field sound pressure are obtained with the active

  14. Barriers Affecting Physical Activity in Rural Communities: Perceptions of Parents and Children

    Science.gov (United States)

    McWhinney, Sharon; McDonald, Andrea; Dawkins-Moultin, Lenna; Outley, Corliss; McKyer, E. Lisako; Thomas, Audrene

    2011-01-01

    A comprehensive understanding of the barriers inhibiting physical activity among children is critical in the fight against childhood obesity. This qualitative interview study examined parents' and children's perceptions of the barriers to physical activity in rural communities of low socioeconomic status. Parents and children concurred that the…

  15. A qualitative exploration of barriers and motivators to physical activity participation in women treated for breast cancer.

    Science.gov (United States)

    Brunet, Jennifer; Taran, Samantha; Burke, Shaunna; Sabiston, Catherine M

    2013-01-01

    The adoption and maintenance of a physically active lifestyle among women after breast cancer is an important priority for public health and rehabilitation science. The purpose of this qualitative study was to explore breast cancer survivors' perceptions of the factors influencing their ability to maintain a self-directed physical activity program. Nine women participated in semi-structured, in-depth interviews. Data were coded into perceived barriers and motivators to maintenance of physical activity using thematic analysis. Women identified a range of physical (e.g. cancer-related physical symptoms), environmental/organizational (e.g. bad weather, lack of equipment/facilities, lack of knowledge, time constraints) and psychosocial (e.g. lack of motivation, low social support, low confidence/skill) barriers. They also identified perceived physical (e.g. weight management, health improvement or maintenance, increase energy) and psychosocial (e.g. improve body image, experience enjoyment, social support, positive emotions) motivators. These findings are consistent with research on barriers and motivators to physical activity initiation, and can be used to develop self-directed physical activity programs that target active breast cancer survivors to sustain regular engagement. Furthermore, the barriers and motivators identified represent key variables for further investigation. The present study identifies a number of perceived physical, psychosocial and organizational/environmental barriers to naturally occurring physical activity participation among active breast cancer survivors that should be addressed to ensure they maintain a physically active lifestyle This study also provides evidence that comprehensive approaches that address physical and psychosocial motivators to physical activity should be developed to assist women with a history of breast cancer maintain their physical activity levels.

  16. Financing Solar Energy Systems with Energy Savings Performance Contracts in the Federal Sector: Results of a Survey on Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Gee, R. C.; LaPorta, C.

    1999-08-17

    This report summarizes the findings of an investigation into financing solar energy systems for the Federal sector. The objectives of the investigation were (1) to identify the barriers that impede companies from using Energy Savings Performance Contracts (ESPCs) to develop solar energy projects for Federal facilities, and (2) to clarify the impacts of Federal contracting requirements on energy service companies' use of ESPCs. Twenty-four representatives of energy service companies agreed to be interviewed. Their responses indicate that these are the primary barriers to greater use of ESPCs: the relatively long payback periods for investments in solar technologies; the length of the ESPC process; the cost of certain contractual requirements regarding wages and financing; and a lack of knowledge about the actual cost and reliability of solar systems. The report proposes a number of actions the government could take to remove these barriers, including (1) streamlining and shortening the ESPC process and (2) doing more to inform both government agencies and energy service companies about the costs and benefits of solar systems.

  17. 11Li Breakup on 208 at energies around the Coulomb barrier.

    Science.gov (United States)

    Fernández-García, J P; Cubero, M; Rodríguez-Gallardo, M; Acosta, L; Alcorta, M; Alvarez, M A G; Borge, M J G; Buchmann, L; Diget, C A; Falou, H A; Fulton, B R; Fynbo, H O U; Galaviz, D; Gómez-Camacho, J; Kanungo, R; Lay, J A; Madurga, M; Martel, I; Moro, A M; Mukha, I; Nilsson, T; Sánchez-Benítez, A M; Shotter, A; Tengblad, O; Walden, P

    2013-04-05

    The inclusive breakup for the (11)Li + (208)Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of (9)Li following the (11)Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the (11)Li continuum at low excitation energy.

  18. 11Li Breakup on 208Pb at Energies Around the Coulomb Barrier

    DEFF Research Database (Denmark)

    Fernández-García, J.P.; Cubero, M.; Rodríguez-Gallardo, M.

    2013-01-01

    The inclusive breakup for the 11Li+208Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of 9Li following the 11Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation...... theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear...... and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the 11Li continuum at low excitation energy....

  19. Disentangling complete and incomplete fusion for 9Be+187Re system at near barrier energies

    International Nuclear Information System (INIS)

    Kharab, Rajesh; Chahal, Rajiv; Rajiv Kumar

    2015-01-01

    The breakup of projectile before fusion leads to some unusual fusion mechanisms like incomplete fusion (ICF) and sequential complete fusion (SCF). Experimentally, it is not possible to separate SCF events from direct complete fusion (DCF). However, the complete fusion and incomplete fusion can be measured separately. Theoretically it is very difficult to calculate the complete and incomplete fusion cross section separately using different models. Very recently A. Diaz-Torres has developed a computer code platypus based on classical dynamical model wherein the complete and incomplete fusion cross sections are calculated separately. But this model is found to work very well at energies above the barrier energy. Here we have attempted to extrapolate the results of the code platypus by using simple Wong's formula in conjunction with the energy dependent Woods-Saxon potential (EDWSP) in the below barrier energy region

  20. Closing the Energy Efficiency Gap: A study linking demographics with barriers to adopting energy efficiency measures in the home

    International Nuclear Information System (INIS)

    Pelenur, Marcos J.; Cruickshank, Heather J.

    2012-01-01

    This paper presents a study which linked demographic variables with barriers affecting the adoption of domestic energy efficiency measures in large UK cities. The aim was to better understand the ‘Energy Efficiency Gap’ and improve the effectiveness of future energy efficiency initiatives. The data for this study was collected from 198 general population interviews (1.5–10 min) carried out across multiple locations in Manchester and Cardiff. The demographic variables were statistically linked to the identified barriers using a modified chi-square test of association (first order Rao–Scott corrected to compensate for multiple response data), and the effect size was estimated with an odds-ratio test. The results revealed that strong associations exist between demographics and barriers, specifically for the following variables: sex; marital status; education level; type of dwelling; number of occupants in household; residence (rent/own); and location (Manchester/Cardiff). The results and recommendations were aimed at city policy makers, local councils, and members of the construction/retrofit industry who are all working to improve the energy efficiency of the domestic built environment. -- Highlights: ► 7 demographic variables linked to 8 barriers to adopting energy efficiency measures. ► A modified chi-square test for association was used (first order Rao–Scott corrected). ► Results revealed strong associations between most of the demographics and barriers. ► Data was collected from 198 interviews in the UK cities of Manchester and Cardiff. ► Specific recommendations are presented for regional policy makers and industry.

  1. Alpha-production channels in 6Li+159Tb at energies around the Coulomb barrier

    International Nuclear Information System (INIS)

    Pradhan, M.K.; Mukherjee, A.; Roy, S.; Basu, P.; Goswami, A.; Saha Sarkar, M.; Kshetri, R.; Roy Chowdhury, R.; Ray, M.; Santra, S.; Kailas, S.; Parkar, V.V.; Palit, R.

    2010-01-01

    In order to investigate what are the dominant processes that might contribute to the inclusive α-particle channels, very recently measurements have been performed by the characteristic γ-ray method for the system 6 Li+ 159 Tb at energies below and above the Coulomb barrier (V B = 26.9 MeV)

  2. Barriers and drivers for energy efficiency : Different perspectives from an exploratory study in the Netherlands

    NARCIS (Netherlands)

    Cagno, Enrico; Trianni, Andrea; Worrell, Ernst; Miggiano, Federica

    2014-01-01

    Increased energy efficiency represents a crucial opportunity for European industrial sustainability, but several barriers still need to be tackled, as recent policies have not often succeeded as expected. Thus, it is crucial to understand the existing mismatches between the perception of

  3. Response of wave-dominated and mixed-energy barriers to storms

    NARCIS (Netherlands)

    Masselink, G.; Heteren, S. van

    2014-01-01

    Wave-dominated and mixed-energy barriers are extremely dynamic landforms, responding to processes operating over a spectrum of time scales, ranging from daily-to-monthly fluctuations related to storm and post-storm conditions, to century-to-millennium-scale evolution driven by relative sea-level

  4. Barriers to installing innovative energy systems in existing housing stock identified

    NARCIS (Netherlands)

    Hoppe, Thomas

    2013-01-01

    Several barriers to upgrading existing social housing with innovative energy systems (IES) have been identified by a study of eight large-scale renovation projects in the Netherlands. These include a lack of trust between stakeholders, opposition from tenants on grounds of increased costs or delays,

  5. New light on an old problem: Reflections on barriers and enablers of distributed energy

    International Nuclear Information System (INIS)

    Szatow, Anthony; Quezada, George; Lilley, Bill

    2012-01-01

    This viewpoint article, New light on an Old Problem, aims to stimulate thought and discussion on pathways to rapid emission reduction trajectories. It considers briefly the history of the Australian energy system and recent attempts to support emerging, distributed energy supply systems, before exploring the importance of new energy supply models and how they may emerge organically, ahead of further policy and regulatory shifts in Australia. The article is shaped by extensive primary research, literature review and engagement with policy makers, industry and community organisations, energy market institutions, colleagues and others over a period of four years. It outlines how new business models may reduce emissions ahead of policy and regulation, and the importance of keeping an open mind when considering ‘barriers’ to distributed energy. We hope this article will spark interest and dialogue with colleagues who may be experiencing and grappling with similar challenges. - Research highlights: ► We discuss documented barriers to distributed energy. ► We draw on socio-technical system literature and our research experience to outline a possible solution to distributed energy barriers. ► We describe a hypothetical energy service business model, led by the property sector, as a catalyst for energy market change. ► We outline reasons for our confidence in this property sector led energy services model.

  6. Organizational human factors as barriers to energy efficiency in electrical motors systems in industry

    International Nuclear Information System (INIS)

    Sola, Antonio Vanderley Herrero; Augusto de Paula, Xavier Antonio

    2007-01-01

    This paper presents a study accomplished in the State of Parana in Southern Brazil, aiming at verifying the correlation between organizational human factors (OHF) and the level of energy losses in organizations. The purpose is to subsidize the formularization of institutional policies in organizations to improve the energy efficiency in the productive sector. The research was carried out in ten industries of the following sectors: pulp and paper; food; wood and chemical products. The losses of electric energy were determined in motor systems with the aid of a mathematical model and the evaluation of 27 OHF identified in the literature review was made with the supervisors in the industries by means of a structurized questionnaire. Seven OHF had presented significant correlation with energy losses and six of them are inversely proportional to the losses, in accordance with linear regression analysis. The inversely proportional factors to the losses also with significant correlation are considered determinative OHF and constitute barriers for energy efficiency in organizations. These barriers are linked with the following organizational areas: management system; education of employees; strategical vision. The study recommends the implementation of the determinative OHF in organizations as a way to transpose the human barriers for energy efficiency

  7. A systematic review of perceived barriers and motivators to physical activity after stroke.

    Science.gov (United States)

    Nicholson, Sarah; Sniehotta, Falko F; van Wijck, Frederike; Greig, Carolyn A; Johnston, Marie; McMurdo, Marion E T; Dennis, Martin; Mead, Gillian E

    2013-07-01

    Physical fitness is impaired after stroke, may contribute to disability, yet is amenable to improvement through regular physical activity. To facilitate uptake and maintenance of physical activity, it is essential to understand stroke survivors' perceived barriers and motivators. Therefore, we undertook a systematic review of perceived barriers and motivators to physical activity after stroke. Electronic searches of EMBASE, Medline, CINAHL, and PsychInfo were performed. We included peer-reviewed journal articles, in English, between 1 January 1966 and 30 August 2010 reporting stroke survivors' perceived barriers and motivators to physical activity. Searches identified 73,807 citations of which 57 full articles were retrieved. Six articles were included, providing data on 174 stroke survivors (range 10 to 83 per article). Two reported barriers and motivators, two reported only motivators, and two reported only barriers. Five were qualitative articles and one was quantitative. The most commonly reported barriers were lack of motivation, environmental factors (e.g. transport), health concerns, and stroke impairments. The most commonly reported motivators were social support and the need to be able to perform daily tasks. This review has furthered our understanding of the perceived barriers and motivators to physical activity after a stroke. This review will enable the development of tailored interventions to target barriers, while building upon perceived motivators to increase and maintain stroke survivors' physical activity. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.

  8. Is the perception of time pressure a barrier to healthy eating and physical activity among women?

    Science.gov (United States)

    Welch, Nicky; McNaughton, Sarah A; Hunter, Wendy; Hume, Clare; Crawford, David

    2009-07-01

    To describe the proportion of women reporting time is a barrier to healthy eating and physical activity, the characteristics of these women and the perceived causes of time pressure, and to examine associations between perceptions of time as a barrier and consumption of fruit, vegetables and fast food, and physical activity. A cross-sectional survey of food intake, physical activity and perceived causes of time pressure. A randomly selected community sample. A sample of 1580 women self-reported their food intake and their perceptions of the causes of time pressure in relation to healthy eating. An additional 1521 women self-reported their leisure-time physical activity and their perceptions of the causes of time pressure in relation to physical activity. Time pressure was reported as a barrier to healthy eating by 41% of the women and as a barrier to physical activity by 73%. Those who reported time pressure as a barrier to healthy eating were significantly less likely to meet fruit, vegetable and physical activity recommendations, and more likely to eat fast food more frequently. Women reporting time pressure as a barrier to healthy eating and physical activity are less likely to meet recommendations than are women who do not see time pressure as a barrier. Further research is required to understand the perception of time pressure issues among women and devise strategies to improve women's food and physical activity behaviours.

  9. Preferences for and Barriers to Formal and Informal Athletic Training Continuing Education Activities

    Science.gov (United States)

    Armstrong, Kirk J.; Weidner, Thomas G.

    2011-01-01

    Context: Our previous research determined the frequency of participation and perceived effect of formal and informal continuing education (CE) activities. However, actual preferences for and barriers to CE must be characterized. Objective: To determine the types of formal and informal CE activities preferred by athletic trainers (ATs) and barriers to their participation in these activities. Design: Cross-sectional study. Setting: Athletic training practice settings. Patients or Other Participants: Of a geographically stratified random sample of 1000 ATs, 427 ATs (42.7%) completed the survey. Main Outcome Measure(s): As part of a larger study, the Survey of Formal and Informal Athletic Training Continuing Education Activities (FIATCEA) was developed and administered electronically. The FIATCEA consists of demographic characteristics and Likert scale items (1 = strongly disagree, 5 = strongly agree) about preferred CE activities and barriers to these activities. Internal consistency of survey items, as determined by Cronbach α, was 0.638 for preferred CE activities and 0.860 for barriers to these activities. Descriptive statistics were computed for all items. Differences between respondent demographic characteristics and preferred CE activities and barriers to these activities were determined via analysis of variance and dependent t tests. The α level was set at .05. Results: Hands-on clinical workshops and professional networking were the preferred formal and informal CE activities, respectively. The most frequently reported barriers to formal CE were the cost of attending and travel distance, whereas the most frequently reported barriers to informal CE were personal and job-specific factors. Differences were noted between both the cost of CE and travel distance to CE and all other barriers to CE participation (F1,411 = 233.54, P formal CE activities. The same barriers (eg, cost, travel distance) to formal CE appeared to be universal to all ATs. Informal CE was

  10. Perceived benefits and barriers to leisure-time physical activity during pregnancy in previously inactive and active women.

    Science.gov (United States)

    Da Costa, Deborah; Ireland, Kierla

    2013-01-01

    This study compared perceived benefits and barriers to leisure-time physical activity during pregnancy among women who were insufficiently active or inactive before pregnancy. Eighty-two pregnant women completed questionnaires assessing leisure-time physical activity benefits/barriers, exercise self-efficacy, social support, depressed mood, pre-pregnancy and current physical activity and fatigue. Multivariable regression analyses identified factors associated with exercise benefits/barriers for the two pre-pregnancy leisure-time physical activity groups. Both pre-pregnancy leisure-time physical activity groups reported more benefits than barriers to exercise during pregnancy. Previously inactive women reported fewer perceived benefits and greater perceived barriers to leisure-time physical activity during pregnancy. Higher self-efficacy for exercise during pregnancy was significantly associated with greater benefits of leisure-time physical activity during pregnancy for both groups. Less family support for exercise and lower self-efficacy for exercise were significantly related to greater leisure-time physical activity barriers during pregnancy for previously inactive women. Lower self-efficacy for exercise, higher depressed mood scores, and younger age were associated with greater leisure-time physical activity barriers for active women. Findings suggest that the intensities of perceived leisure-time physical activity benefits and barriers during pregnancy differ for women, depending on their pre-pregnancy leisure-time physical activity status. Consideration of pre-pregnancy leisure-time physical activity status may thus be important when tailoring strategies to overcome barriers to promote initiation and maintenance of physical activity during pregnancy.

  11. Research on the application of active sound barriers for the transformer noise abatement

    Directory of Open Access Journals (Sweden)

    Hu Sheng

    2016-01-01

    Full Text Available Sound barriers are a type of measure most commonly used in the noise abatement of transformers. In the noise abatement project of substations, the design of sound barriers is restrained by the portal frames which are used to hold up outgoing lines from the main transformers, which impacts the noise reduction effect. If active sound barriers are utilized in these places, the noise diffraction of sound barriers can be effectively reduced. At a 110kV Substation, an experiment using a 15-channel active sound barrier has been carried out. The result of the experiment shows that the mean noise reduction value (MNRV of the noise measuring points at the substation boundary are 1.5 dB (A. The effect of the active noise control system is impacted by the layout of the active noise control system, the acoustic environment on site and the spectral characteristic of the target area.

  12. Barriers to activity and participation for stroke survivors in rural China.

    Science.gov (United States)

    Zhang, Lifang; Yan, Tiebin; You, Liming; Li, Kun

    2015-07-01

    To investigate environmental barriers reported by stroke survivors in the rural areas of China and to determine the impact of environmental barriers on activity and participation relative to demographic characteristics and body functioning. Cross-sectional survey. Structured interviews in the participants' homes. Community-dwelling stroke survivors in the rural areas of China (N=639). Not applicable. Activity and participation (Chinese version of the World Health Organization Disability Assessment Schedule 2.0), environmental barriers (Craig Hospital Inventory of Environmental Factors), neurological function (Canadian Neurological Scale), cognitive function (Abbreviated Mental Test), and depression (6-item Hamilton Rating Scale for Depression). Physical/structural barriers are the major impediment to activity and participation for these participants (odds ratio, 1.86 and 1.99 for activity and participation, respectively; Penvironmental barriers to be decreased and eliminated first. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  13. Socio-cultural barriers to the development of a sustainable energy system - the case of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Kjerulf Petersen, L.; Holst Andersen, A.

    2009-02-15

    Any transition to a more sustainable energy system, radically reducing greenhouse gas emissions, is bound to run in to a host of different barriers - technological and economic, but also socio-cultural. This will also be the case for any large-scale application of hydrogen as energy carrier, especially if the system is going to be based on renewable energy sources. The aim of these research notes is to review and discuss major socio-cultural barriers to new forms of energy supply in general and to hydrogen specifically. Reaching sufficient reductions in greenhouse gas emissions may require more than large-scale dissemination of renewable energy sources. Also reductions or moderations in energy demand may be necessary. Hence, a central point in the research note is to consider not only socio-cultural obstacles for changing technologies in energy production, distribution and consumption but also obstacles for changing the scale of energy consumption, i.e. moderating the growth in how much energy is consumed or even reducing consumption volumes. (au)

  14. Anisotropic Lithium Insertion Behavior in Silicon Nanowires: Binding Energy, Diffusion Barrier, and Strain Effect

    KAUST Repository

    Zhang, Qianfan; Cui, Yi; Wang, Enge

    2011-01-01

    Silicon nanowires (SiNWs) have recently been shown to be promising as high capacity lithium battery anodes. SiNWs can be grown with their long axis along several different crystallographic directions. Due to distinct atomic configuration and electronic structure of SiNWs with different axial orientations, their lithium insertion behavior could be different. This paper focuses on the characteristics of single Li defects, including binding energy, diffusion barriers, and dependence on uniaxial strain in [110], [100], [111], and [112] SiNWs. Our systematic ab initio study suggests that the Si-Li interaction is weaker when the Si-Li bond direction is aligned close to the SiNW long axis. This results in the [110] and [111] SiNWs having the highest and lowest Li binding energy, respectively, and it makes the diffusion barrier along the SiNW axis lower than other pathways. Under external strain, it was found that [110] and [001] SiNWs are the most and least sensitive, respectively. For diffusion along the axial direction, the barrier increases (decreases) under tension (compression). This feature results in a considerable difference in the magnitude of the energy barrier along different diffusion pathways. © 2011 American Chemical Society.

  15. Anisotropic Lithium Insertion Behavior in Silicon Nanowires: Binding Energy, Diffusion Barrier, and Strain Effect

    KAUST Repository

    Zhang, Qianfan

    2011-05-19

    Silicon nanowires (SiNWs) have recently been shown to be promising as high capacity lithium battery anodes. SiNWs can be grown with their long axis along several different crystallographic directions. Due to distinct atomic configuration and electronic structure of SiNWs with different axial orientations, their lithium insertion behavior could be different. This paper focuses on the characteristics of single Li defects, including binding energy, diffusion barriers, and dependence on uniaxial strain in [110], [100], [111], and [112] SiNWs. Our systematic ab initio study suggests that the Si-Li interaction is weaker when the Si-Li bond direction is aligned close to the SiNW long axis. This results in the [110] and [111] SiNWs having the highest and lowest Li binding energy, respectively, and it makes the diffusion barrier along the SiNW axis lower than other pathways. Under external strain, it was found that [110] and [001] SiNWs are the most and least sensitive, respectively. For diffusion along the axial direction, the barrier increases (decreases) under tension (compression). This feature results in a considerable difference in the magnitude of the energy barrier along different diffusion pathways. © 2011 American Chemical Society.

  16. Socio-demographic and behavioral variation in barriers to leisure-time physical activity.

    Science.gov (United States)

    Borodulin, Katja; Sipilä, Noora; Rahkonen, Ossi; Leino-Arjas, Päivi; Kestilä, Laura; Jousilahti, Pekka; Prättälä, Ritva

    2016-02-01

    We examined the socio-demographic and behavioral determinants of perceived barriers to leisure-time physical activity (LTPA) in a population-based sample of working-aged adults. Data comprised the National FINRISK 2002 Study, a population-based health examination study. Analyses were restricted to those aged 25-64 years and who perceived that their amount of LTPA did not reach sufficient levels. They reported barriers to LTPA, defined as a lack of time, motivation and lack of companionship to be active with, as well as high expenses. Age, education, household income, employment status, family type, physical activity, smoking and body mass index (BMI) were included as explanatory variables. Lack of time was the most frequent barrier. Each barrier was explained by a different set of factors that also varied between genders. The strongest and most systematic associations with the barriers were found for age, employment status and family type. Lack of time was less often reported as a barrier among the unemployed, singles without children and older people. Lacking motivation as a barrier was most common among singles without children. High expenses as a barrier was more often reported by the unemployed, and less often reported in the highest income group. When considering actions to promote LTPA, there is not one single solution, because the perceived barriers vary by population subgroups. © 2015 the Nordic Societies of Public Health.

  17. A qualitative theory guided analysis of stroke survivors' perceived barriers and facilitators to physical activity.

    Science.gov (United States)

    Nicholson, Sarah L; Donaghy, Marie; Johnston, Marie; Sniehotta, Falko F; van Wijck, Frederike; Johnston, Derek; Greig, Carolyn; McMurdo, Marion E T; Mead, Gillian

    2014-01-01

    After stroke, physical activity and physical fitness levels are low, impacting on health, activity and participation. It is unclear how best to support stroke survivors to increase physical activity. Little is known about the barriers and facilitators to physical activity after stroke. Thus, our aim was to explore stroke survivors' perceived barriers and facilitators to physical activity. Semi-structured interviews with 13 ambulatory stroke survivors exploring perceived barriers and facilitators to physical activity post stroke were conducted in participants' homes, audio-recorded and transcribed verbatim. The Theoretical Domains Framework (TDF) informed content analysis of the interview transcripts. Data saturation was reached after interviews with 13 participants (median age of 76 years (inter-quartile range (IQR) = 69-83 years). The median time since stroke was 345 d (IQR = 316-366 d). The most commonly reported TDF domains were "beliefs about capabilities", "environmental context and resources" and "social influence". The most commonly reported perceived motivators were: social interaction, beliefs of benefits of exercise, high self-efficacy and the necessity of routine behaviours. The most commonly reported perceived barriers were: lack of professional support on discharge from hospital and follow-up, transport issues to structured classes/interventions, lack of control and negative affect. Stroke survivors perceive several different barriers and facilitators to physical activity. Stroke services need to address barriers to physical activity and to build on facilitators to promote physical activity after stroke. Physical activity post stroke can improve physical fitness and function, yet physical activity remains low among stroke survivors. Understanding stroke survivors' perceived barriers and facilitators to physical activity is essential to develop targeted interventions to increase physical activity. Beliefs about capabilities, environmental

  18. Testing Convergence of Different Free-Energy Methods in a Simple Analytical System with Hidden Barriers

    Directory of Open Access Journals (Sweden)

    S. Alexis Paz

    2018-03-01

    Full Text Available In this work, we study the influence of hidden barriers on the convergence behavior of three free-energy calculation methods: well-tempered metadynamics (WTMD, adaptive-biasing forces (ABF, and on-the-fly parameterization (OTFP. We construct a simple two-dimensional potential-energy surfaces (PES that allows for an exact analytical result for the free-energy in any one-dimensional order parameter. Then we chose different CV definitions and PES parameters to create three different systems with increasing sampling challenges. We find that all three methods are not greatly affected by the hidden-barriers in the simplest case considered. The adaptive sampling methods show faster sampling while the auxiliary high-friction requirement of OTFP makes it slower for this case. However, a slight change in the CV definition has a strong impact in the ABF and WTMD performance, illustrating the importance of choosing suitable collective variables.

  19. Breakup mechanisms for 7Li + 197Au, 204Pb systems at sub-barrier energies

    Directory of Open Access Journals (Sweden)

    Luong D.H.

    2013-12-01

    Full Text Available Coincidence measurements of breakup fragments were carried out for the 7Li + 197Au and 204Pb systems at sub-barrier energies. The mechanisms triggering breakup, and time-scales of each process, were identified through the reaction Q-values and the relative energy of the breakup fragments. Binary breakup of 7Li were found to be predominantly triggered by nucleon transfer, with p-pickup leading to 8Be → α + α decay being the preferred breakup mode. From the time-scales of each process, the coincidence yields were separated into prompt and delayed components, allowing the identification of breakup process important in the suppression of complete fusion of 7Li at above-barrier energies.

  20. Overcoming financial barriers to wider use of renewable energy technology in Africa

    International Nuclear Information System (INIS)

    Davidson, O.R.; Turkson, J.

    2001-01-01

    Future energy demand in Africa will rise dramatically due to development desires and increased industrial needs. Coping with this demand will pose a serious challenge because of the economic and environmental constraints of the continent. Exploiting its vast renewable energy sources for this purpose will assist greatly, but financial and other barriers to the rapid growth of associated technologies are significant. This paper explores measures that can be implemented to reduce these financial barriers. The analyses, which are based on lessons from experiences in and out of the region, show that replicating and enhancing current initiatives along with the implementation of suggested policy options could substantially increase the use of renewable energy technologies in Africa. (author)

  1. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells.

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-28

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  2. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells

    Science.gov (United States)

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-01

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  3. Organizational, interface, and financial barriers to the commercial development of community energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Schladale, R.; Ritschard, R.

    1979-12-01

    The scope of this analysis was limited to systems producing electricity - the output of a community energy system typically falling in the range 10 kW to 150 MW. The purpose of this study was to identify the barriers that groups and individuals will face when attempting to commercialize community energy systems. Three particular classes of barriers were investigated: those within the organization attempting the commercialization, those that arise from attempts to link the community system with an electric utility, and those that impede the flow of investment capital into community energy systems. In summary, three general observations regarding community energy systems may be distilled from this study. First, although many barriers exist to the commercialization of the systems, few if any appear unresolvable. Perhaps most challenginng will be the problem of expanding the use of cogeneration and municipal sold waste while at the same time maintaining or improving ambient air quality. Second, the financial subsidies required to make community systems competitive are not extraordinary. Indeed, with the exception of photovoltaics they should not amount to more than about 10% of capital cost of the new systems, and mass production may eliminate the need for subsidies altogether at some point in the future. Third, the administrative and regulatory procedures required to make community energy systems viable appear to be taking shape in a positive and timely fashion.

  4. A barrier analysis for the development of distributed energy in China: A case study in Fujian province

    International Nuclear Information System (INIS)

    Liu, Jian; Wang, Run; Sun, Yanwei; Lin, Yanjie; Xiao, Lishan

    2013-01-01

    Distributed energy (DE) is receiving lots of attention from the Chinese government. A number of DE projects have been constructed in China. However, there are still numerous problems with DE projects. What hinders the development of DE in China? The Huadian Jimei distributed energy project (HJDE) is a typical DE building project that was not completed successfully. This paper focuses on this DE project to explore the barriers to DE development. The research group conducted 13 semi-structured interviews with representatives of institutions and corporations involved in the HJDE project to collect information. Based on the information, three types of problems were determined, and the results indicate that these conflicts between the core stakeholders make DE projects unsuccessful. These problems result from institutional barriers to DE, rooting in the development policy and the current energy market. Moreover, several key stakeholders are not able to play an active role in the design or management of DE projects. The Chinese government will put a much greater effort into the development of future DE projects. Many national support policies and rules will be announced, which are easy to practical use. Under these conditions, 1000 DE projects will be successfully completed until 2015. - Highlights: • Using stakeholder analysis, this paper focuses on one typical building DE project. • Conflicts between core stakeholders make the DE project cannot be completed. • The barriers are related to the role of electricity consumers in DE projects. • The barriers are also related to current Chinese natural gas and LNG market. • Drivers such as regulation, incentives and so on should be built and modified

  5. Current-induced changes of migration energy barriers in graphene and carbon nanotubes.

    Science.gov (United States)

    Obodo, J T; Rungger, I; Sanvito, S; Schwingenschlögl, U

    2016-05-21

    An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative.

  6. Current-induced changes of migration energy barriers in graphene and carbon nanotubes

    KAUST Repository

    Obodo, Tobechukwu Joshua

    2016-04-29

    An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative. © 2016 The Royal Society of Chemistry.

  7. The Schottky energy barrier dependence of charge injection in organic light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, I.H.; Davids, P.S.; Smith, D.L. [Los Alamos National Laboratory, Los Alamos, New Mexico87545 (United States); Barashkov, N.N.; Ferraris, J.P. [The University of Texas at Dallas, Richardson, Texas75083 (United States)

    1998-04-01

    We present device model calculations of the current{endash}voltage (I{endash}V) characteristics of organic diodes and compare them with measurements of structures fabricated using MEH-PPV. The structures are designed so that all of the current is injected from one contact. The I{endash}V characteristics are considered as a function of the Schottky energy barrier to charge injection from the contact. Experimentally, the Schottky barrier is varied from essentially zero to more than 1 eV by using different metal contacts. A consistent description of the device I{endash}V characteristics is obtained as the Schottky barrier is varied from small values, less than about 0.4 eV, where the current flow is space-charge limited to larger values where it is contact limited. {copyright} {ital 1998 American Institute of Physics.}

  8. The Schottky energy barrier dependence of charge injection in organic light-emitting diodes

    Science.gov (United States)

    Campbell, I. H.; Davids, P. S.; Smith, D. L.; Barashkov, N. N.; Ferraris, J. P.

    1998-04-01

    We present device model calculations of the current-voltage (I-V) characteristics of organic diodes and compare them with measurements of structures fabricated using MEH-PPV. The structures are designed so that all of the current is injected from one contact. The I-V characteristics are considered as a function of the Schottky energy barrier to charge injection from the contact. Experimentally, the Schottky barrier is varied from essentially zero to more than 1 eV by using different metal contacts. A consistent description of the device I-V characteristics is obtained as the Schottky barrier is varied from small values, less than about 0.4 eV, where the current flow is space-charge limited to larger values where it is contact limited.

  9. Perceived benefits and barriers of physical activity: A social marketing formative study.

    Science.gov (United States)

    Rundle-Thiele, Sharyn; Kubacki, Krzysztof; Gruneklee, Naomi

    2016-01-01

    The aim of this study was to gain formative research insights that can be used to design social marketing campaigns. One thousand four hundred fifty-nine people participated in an online survey. Factor analysis was undertaken to establish perceived benefits and barriers, and indexes were created for barriers, benefits, and healthy living knowledge. Four attitude groups were formed and analysis of variance was undertaken to explore group differences. Consumers with high perceived barriers report less physical activity than consumers with low perceived barriers to exercise. The current study provides evidence to suggest that exchange theory can offer important insights to inform social marketing intervention planning.

  10. Current-induced changes of migration energy barriers in graphene and carbon nanotubes

    Science.gov (United States)

    Obodo, J. T.; Rungger, I.; Sanvito, S.; Schwingenschlögl, U.

    2016-05-01

    An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative.An electron current can move atoms in a nanoscale device with important consequences for the device operation and breakdown. We perform first principles calculations aimed at evaluating the possibility of changing the energy barriers for atom migration in carbon-based systems. In particular, we consider the migration of adatoms and defects in graphene and carbon nanotubes. Although the current-induced forces are large for both the systems, in graphene the force component along the migration path is small and therefore the barrier height is little affected by the current flow. In contrast, the same barrier is significantly reduced in carbon nanotubes as the current increases. Our work also provides a real-system numerical demonstration that current-induced forces within density functional theory are non-conservative. Electronic supplementary information (ESI) available. See DOI: 10.1039/C6NR00534A

  11. NOVEL TSUNAMI BARRIERS AND THEIR APPLICATIONS FOR HYDROELECTRIC ENERGY STORAGE, FISH FARMING, AND FOR LAND RECLAMATION

    Directory of Open Access Journals (Sweden)

    Hans J. Scheel

    2014-10-01

    Full Text Available The tsunami hazard can be mitigated if the destructive waves generated from earthquakes and landslides can be reflected by a stable submerged vertical barrier before striking coastal communities or important structures. Building such deep walls by conventional submarine technology is difficult. The present study describes the principle and the erection of such submarine defensive walls by a relatively simple efficient and economic technology. This technology is based on lowering high- strength steel fences with horizontal anchors, or two parallel steel fences with distance holders, into the sea and fixing them with rocks deposited from top. Dredged material like gravel or sand can be used for additional filling. This Tsunami-Flooding Barrier (TFB extends a few meters above sea level and carries on top a concrete supply and service road protected on both sides against storm waves by concrete walls. Replaceable surge stoppers (parapets, wave return walls prevent overtopping and erosion of the seaward barrier face. The TFBs protect the coastline against tsunami and the highest storm waves from hurricanes, but also can provide protection from oil spills or other contaminations from the ocean and thus protect flora, fauna, coral reefs and beaches. Channels and gates allow navigation and can be closed quickly upon a tsunami or storm warning. The construction costs can be eventually compensated by using the reservoirs between coast and barriers for hydroelectric energy storage (using pump-turbines in the barriers or for fish-farming, or alternatively the reservoir can be filled with rocks, rubble, gravel, sand and covered with soil in order to reclaim new land. Tidal energy can be generated by installing turbines within these barriers. Also, this submarine architecture may be applied to protect pillars of bridges and offshore platforms, and for erecting “roads” into the sea to connect near-shore platforms and wind-parks with the coast and

  12. 78 FR 4983 - Proposed Information Collection; Women Veterans Healthcare Barriers Survey Activity: Comment Request

    Science.gov (United States)

    2013-01-23

    ... Veterans Healthcare Barriers Survey Activity: Comment Request AGENCY: Veterans Health Administration... Healthcare Barriers Survey'' in any correspondence. During the comment period, comments may be viewed online... of automated collection techniques or the use of other forms of information technology. Title: Women...

  13. Barriers to Providing Physical Education and Physical Activity in Victorian State Secondary Schools

    Science.gov (United States)

    Jenkinson, Kate A.; Benson, Amanda C.

    2010-01-01

    An on-line questionnaire was completed by 115 physical education teachers to establish the barriers to their implementation of physical education in Victorian state secondary schools. In addition, the barriers perceived by teachers to impact on students' participation in school-based physical education and physical activity were examined. The…

  14. Barriers for Energy Renovation of Danish Single-Family Houses and Suggested Solutions to Overcome These

    DEFF Research Database (Denmark)

    Mortensen, Andrea; Heiselberg, Per; Knudstrup, Mary-Ann

    2011-01-01

    As much as 40% of the total energy consumption in Denmark is utilized by the building sector and most of this energy is used for heating. Political initiatives have been taken to reduce this amount considerably but for this to happen, the energy consumption of the existing residential housing stock...... must be reduced dramatically. The greatest saving potential is found among the approximately 440.000 standardised single-family houses which were constructed in the 1960’s and 1970’s. It is found that barriers preventing the implementation of this great potential are present in various forms among all...

  15. Characteristics of powdered activated carbon treated with dielectric barrier discharge for electric double-layer capacitors

    International Nuclear Information System (INIS)

    Tashima, Daisuke; Yoshitama, Hiromu; Sakoda, Tatsuya; Okazaki, Akihito; Kawaji, Takayuki

    2012-01-01

    Highlights: ► The specific capacitance of the EDLCs could be improved by oxygen plasma treatment. ► 15 s treated EDLCs showed a 20% increase in capacitance relative to untreated EDLCs. ► The plasma treatment yields EDLCs that are suitable for high-energy applications. - Abstract: The electrochemical properties of electric double-layer capacitors (EDLCs) made with plasma-treated powdered activated carbon (treated using a dielectric barrier discharge) were examined using cyclic voltammetry (CV), Cole–Cole plots, and X-ray photoelectron spectroscopy (XPS). The dielectric barrier discharge method, which operates at atmospheric pressure, dramatically reduces the processing time and does not require vacuum equipment, making it a more practical alternative than low-pressure plasma treatment. The experimental data indicate that the specific capacitance of the EDLCs could be improved by oxygen plasma treatment. Capacitance of EDLCs made with activated carbon treated for 15 s showed 193.5 F/g that 20% increase in the specific capacitance relative to untreated EDLCs. This result indicates that the plasma treatment yields EDLCs that are suitable for high-energy applications. The enhancement of capacitance was mainly attributed to an increase in the BET surface area of the activated carbon and the creation of carboxyl groups on the surface of the carbon. The carboxyl groups induced oxidation–reduction reactions in the presence of O 2 which was included in the operation gas. In addition, the carboxyl groups improved the penetration of the electrolyte solution into the carbon electrodes.

  16. A novel method of calculating the energy deposition curve of nanosecond pulsed surface dielectric barrier discharge

    International Nuclear Information System (INIS)

    He, Kun; Wang, Xinying; Lu, Jiayu; Cui, Quansheng; Pang, Lei; Di, Dongxu; Zhang, Qiaogen

    2015-01-01

    To obtain the energy deposition curve is very important in the fields to which nanosecond pulse dielectric barrier discharges (NPDBDs) are applied. It helps the understanding of the discharge physics and fast gas heating. In this paper, an equivalent circuit model, composed of three capacitances, is introduced and a method of calculating the energy deposition curve is proposed for a nanosecond pulse surface dielectric barrier discharge (NPSDBD) plasma actuator. The capacitance C d and the energy deposition curve E R are determined by mathematically proving that the mapping from C d to E R is bijective and numerically searching one C d that satisfies the requirement for E R to be a monotonically non-decreasing function. It is found that the value of capacitance C d varies with the amplitude of applied pulse voltage due to the change of discharge area and is dependent on the polarity of applied voltage. The bijectiveness of the mapping from C d to E R in nanosecond pulse volumetric dielectric barrier discharge (NPVDBD) is demonstrated and the feasibility of the application of the new method to NPVDBD is validated. This preliminarily shows a high possibility of developing a unified approach to calculate the energy deposition curve in NPDBD. (paper)

  17. Assessment of non-cost barriers to renewable energy growth in EU Member States - AEON

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    The accelerated deployment of renewable energy technologies has become a major priority for public policy makers across the globe. In the last two decades, most of the debate concerning the promotion of renewables was focused on the financial support schemes and on improving grid access conditions for renewable electricity. Of course, these are crucial issues which will continue to deserve serious attention in the future. However, during the last few years, the importance of tackling non-financial and non-technical barriers to renewable electricity, heat and transport has gained the attention of many policy analysts. In June 2009, Directive 2009/28/EC on the promotion of the use of energy from renewable sources, entered into force. The articles 13, 14 and 16 of the Directive contain a number of requirements for Member States to address or remove non-cost barriers to the increased deployment of renewable energy sources. This study presents among others an overview of these barriers in all EU Member States; their history, their impact on renewable energy deployment and suggestions for policy solutions, where feasible. Separate studies were carried out for 27 EU-countries and made available in a zip-file.

  18. Critical energy barrier for capillary condensation in mesopores: Hysteresis and reversibility

    International Nuclear Information System (INIS)

    Hiratsuka, Tatsumasa; Tanaka, Hideki; Miyahara, Minoru T.

    2016-01-01

    Capillary condensation in the regime of developing hysteresis occurs at a vapor pressure, P cond , that is less than that of the vapor-like spinodal. This is because the energy barrier for the vapor-liquid transition from a metastable state at P cond becomes equal to the energy fluctuation of the system; however, a detailed mechanism of the spontaneous transition has not been acquired even through extensive experimental and simulation studies. We therefore construct accurate atomistic silica mesopore models for MCM-41 and perform molecular simulations (gauge cell Monte Carlo and grand canonical Monte Carlo) for argon adsorption on the models at subcritical temperatures. A careful comparison between the simulation and experiment reveals that the energy barrier for the capillary condensation has a critical dimensionless value, W c * = 0.175, which corresponds to the thermal fluctuation of the system and depends neither on the mesopore size nor on the temperature. We show that the critical energy barrier W c * controls the capillary condensation pressure P cond and also determines a boundary between the reversible condensation/evaporation regime and the developing hysteresis regime.

  19. Critical energy barrier for capillary condensation in mesopores: Hysteresis and reversibility

    Science.gov (United States)

    Hiratsuka, Tatsumasa; Tanaka, Hideki; Miyahara, Minoru T.

    2016-04-01

    Capillary condensation in the regime of developing hysteresis occurs at a vapor pressure, Pcond, that is less than that of the vapor-like spinodal. This is because the energy barrier for the vapor-liquid transition from a metastable state at Pcond becomes equal to the energy fluctuation of the system; however, a detailed mechanism of the spontaneous transition has not been acquired even through extensive experimental and simulation studies. We therefore construct accurate atomistic silica mesopore models for MCM-41 and perform molecular simulations (gauge cell Monte Carlo and grand canonical Monte Carlo) for argon adsorption on the models at subcritical temperatures. A careful comparison between the simulation and experiment reveals that the energy barrier for the capillary condensation has a critical dimensionless value, Wc* = 0.175, which corresponds to the thermal fluctuation of the system and depends neither on the mesopore size nor on the temperature. We show that the critical energy barrier Wc* controls the capillary condensation pressure Pcond and also determines a boundary between the reversible condensation/evaporation regime and the developing hysteresis regime.

  20. Controlling Schottky energy barriers in organic electronic devices using self-assembled monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, I.H.; Rubin, S.; Zawodzinski, T.A.; Kress, J.D.; Martin, R.L.; Smith, D.L. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Barashkov, N.N.; Ferraris, J.P. [The University of Texas at Dallas, Richardson, Texas 75083 (United States)

    1996-11-01

    We demonstrate tuning of Schottky energy barriers in organic electronic devices by utilizing chemically tailored electrodes. The Schottky energy barrier of Ag on poly[2-methoxy], 5-(2{prime}-ethyl-hexyloxy)- 1,4-phenylene was tuned over a range of more than 1 eV by using self-assembled monolayers (SAM{close_quote}s) to attach oriented dipole layers to the Ag prior to device fabrication. Kelvin probe measurements were used to determine the effect of the SAM{close_quote}s on the Ag surface potential. {ital Ab} {ital initio} Hartree-Fock calculations of the molecular dipole moments successfully describe the surface potential changes. The chemically tailored electrodes were then incorporated in organic diode structures and changes in the metal/organic Schottky energy barriers were measured using an electroabsorption technique. These results demonstrate the use of self-assembled monolayers to control metal/organic interfacial electronic properties. They establish a physical principle for manipulating the relative energy levels between two materials and demonstrate an approach to improve metal/organic contacts in organic electronic devices. {copyright} {ital 1996 The American Physical Society.}

  1. Controlling Schottky energy barriers in organic electronic devices using self-assembled monolayers

    International Nuclear Information System (INIS)

    Campbell, I.H.; Rubin, S.; Zawodzinski, T.A.; Kress, J.D.; Martin, R.L.; Smith, D.L.; Barashkov, N.N.; Ferraris, J.P.

    1996-01-01

    We demonstrate tuning of Schottky energy barriers in organic electronic devices by utilizing chemically tailored electrodes. The Schottky energy barrier of Ag on poly[2-methoxy], 5-(2'-ethyl-hexyloxy)- 1,4-phenylene was tuned over a range of more than 1 eV by using self-assembled monolayers (SAM close-quote s) to attach oriented dipole layers to the Ag prior to device fabrication. Kelvin probe measurements were used to determine the effect of the SAM close-quote s on the Ag surface potential. Ab initio Hartree-Fock calculations of the molecular dipole moments successfully describe the surface potential changes. The chemically tailored electrodes were then incorporated in organic diode structures and changes in the metal/organic Schottky energy barriers were measured using an electroabsorption technique. These results demonstrate the use of self-assembled monolayers to control metal/organic interfacial electronic properties. They establish a physical principle for manipulating the relative energy levels between two materials and demonstrate an approach to improve metal/organic contacts in organic electronic devices. copyright 1996 The American Physical Society

  2. Controlling Schottky energy barriers in organic electronic devices using self-assembled monolayers

    Science.gov (United States)

    Campbell, I. H.; Rubin, S.; Zawodzinski, T. A.; Kress, J. D.; Martin, R. L.; Smith, D. L.; Barashkov, N. N.; Ferraris, J. P.

    1996-11-01

    We demonstrate tuning of Schottky energy barriers in organic electronic devices by utilizing chemically tailored electrodes. The Schottky energy barrier of Ag on poly[2-methoxy, 5-(2'-ethyl-hexyloxy)- 1,4-phenylene was tuned over a range of more than 1 eV by using self-assembled monolayers (SAM's) to attach oriented dipole layers to the Ag prior to device fabrication. Kelvin probe measurements were used to determine the effect of the SAM's on the Ag surface potential. Ab initio Hartree-Fock calculations of the molecular dipole moments successfully describe the surface potential changes. The chemically tailored electrodes were then incorporated in organic diode structures and changes in the metal/organic Schottky energy barriers were measured using an electroabsorption technique. These results demonstrate the use of self-assembled monolayers to control metal/organic interfacial electronic properties. They establish a physical principle for manipulating the relative energy levels between two materials and demonstrate an approach to improve metal/organic contacts in organic electronic devices.

  3. Barriers to and drivers of the adpotion of energy crops by Swedish farmers: An empirical approach

    Energy Technology Data Exchange (ETDEWEB)

    Jonsson, Anna C.; Ostwald, Madelene; Asplund, Therese; Wibeck, Victoria (Linkoeping Univ., Linkoeping (Sweden). The Tema Inst., Centre for Climate Science and Policy Research)

    2011-06-15

    Since the Swedish government and the EU intend to encourage farmers to expand energy crop production, knowledge of the factors motivating adoption decisions is vital to policy success. Earlier studies have demonstrated that important barriers to farmer adoption of energy crops include converting from annual to perennial crops and from traditional crops or production systems to new ones. Economic motivations for changing production systems are strong, but factors such as values (e.g., aesthetics), knowledge (e.g., habits and knowledge of production methods), and legal conditions (e.g., cultivation licenses) are crucial for the change to energy crops. This paper helps fill gaps in the literature regarding why farmers decide to keep or change a production system. Based on a series of focus group interviews with Swedish farmers, the paper explores how farmers frame crop change decisions and what factors they consider most important. The main drivers of and barriers to growing energy crops, according to interviewees, are grouped and discussed in relation to four broad groups of motivational factors identified in the literature, i.e., values, legal conditions, knowledge, and economic factors. The paper ends by discussing whether some barriers could be overcome by policy changes at the national and European levels

  4. Nucleus-size pinning for determination of nucleation free-energy barriers and nucleus geometry

    Science.gov (United States)

    Sharma, Abhishek K.; Escobedo, Fernando A.

    2018-05-01

    Classical Nucleation Theory (CNT) has recently been used in conjunction with a seeding approach to simulate nucleation phenomena at small-to-moderate supersaturation conditions when large free-energy barriers ensue. In this study, the conventional seeding approach [J. R. Espinosa et al., J. Chem. Phys. 144, 034501 (2016)] is improved by a novel, more robust method to estimate nucleation barriers. Inspired by the interfacial pinning approach [U. R. Pedersen, J. Chem. Phys. 139, 104102 (2013)] used before to determine conditions where two phases coexist, the seed of the incipient phase is pinned to a preselected size to iteratively drive the system toward the conditions where the seed becomes a critical nucleus. The proposed technique is first validated by estimating the critical nucleation conditions for the disorder-to-order transition in hard spheres and then applied to simulate and characterize the highly non-trivial (prolate) morphology of the critical crystal nucleus in hard gyrobifastigia. A generalization of CNT is used to account for nucleus asphericity and predict nucleation free-energy barriers for gyrobifastigia. These predictions of nuclei shape and barriers are validated by independent umbrella sampling calculations.

  5. Energy Storage. Teachers Guide. Science Activities in Energy.

    Science.gov (United States)

    Jacobs, Mary Lynn, Ed.

    Included in this science activities energy package for students in grades 4-10 are 12 activities related to energy storage. Each activity is outlined on the front and back of a single sheet and is introduced by a key question. Most of the activities can be completed in the classroom with materials readily available in any community. Among the…

  6. Barriers to physical activity in older adults in Germany: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Moschny Anna

    2011-11-01

    Full Text Available Abstract Background Data on barriers to physical activity in older adults in Germany are scarce. The aim of this study was to analyse barriers to physical activity in a cohort of older adults, allowing comparisons between men and women, and age groups. Methods 1,937 older adults with a median age of 77 (range 72-93 years (53.3% female took part in the 7-year follow-up telephone interviews of the getABI cohort. Participants who stated that they did not get enough physical activity were surveyed with respect to barriers to physical activity. Barriers were analysed for all respondents, as well as by sex and age group for cases with complete data. Multivariate logistic regression analysis was performed to evaluate differences between sexes and age groups. The level of significance (alpha Results 1,607 (83.0% participants stated that they were sufficiently physically active. 286 participants rated their physical activity as insufficient and responded to questions on barriers to physical activity completely. The three most frequently cited barriers were poor health (57.7%, lack of company (43.0%, and lack of interest (36.7%. Lack of opportunities for sports or leisure activities (30.3% vs. 15.6%, and lack of transport (29.0% vs. 7.1% were more frequently stated by female respondents than male respondents. These differences between men and women were significant (p = .003; p Conclusions The present study provides relevant data on barriers to physical activity in older adults. By revealing appreciable differences between men and women, and age groups, this study has implications for efforts to increase older adults' physical activity. Promotion and intervention strategies should consider the barriers and tailor measures to the specific needs of older adults in order to reduce their constraints to physical activity.

  7. ENEA activities on photovoltaic energy

    International Nuclear Information System (INIS)

    Coiante, D.; Messana, C.

    1989-01-01

    Photovoltaic conversion appears to be a promising technology for producing electricity. Photovoltaic (PV) solar cells directly convert sun radiation into electricity, without needing moving parts or any kind of fuel. In a long term perspective, PV conversion is expected to become an integrative energy source; at present, high costs are the main limiting factor of the diffusion of PV technology. Costs can be reduced through the joint effect of technological innovation and mass production: therefore, the Italian strategy consists in promoting the gradual enlargement of production volumes and, at the same time, the introduction of less expensive technologies and processes, as soon as they become available. The main responsibility for PV strategies and activities is assigned to ENEA, the Italian National Commission for Nuclear and Alternative Energy Sources. The ENEA five year plan (1985-1989) had allocated about 100 M$ in the PV sector and, as a result, today ENEA is the main national organization promoting PV energy development. ENEA programs include both in house research and external activities. The latter are carried out by universities and industrial firms and concern the whole PV production process from raw materials to complete systems. In Italy there are three main industrial enterprises which produce PV modules an systems: Italsolar (formerly Pragma, ENI group), Ansaldo (IRI group) and Helios Technology, a private firm. Their total annual production capacity amounts to about 2 MW per shift, and is expected to increase in the near future. In 1986, the whole production has been about 0.7 MW: a substantial share of this production has been marketed abroad, mostly as complete systems. (author). 6 tabs

  8. ROS-activated calcium signaling mechanisms regulating endothelial barrier function.

    Science.gov (United States)

    Di, Anke; Mehta, Dolly; Malik, Asrar B

    2016-09-01

    Increased vascular permeability is a common pathogenic feature in many inflammatory diseases. For example in acute lung injury (ALI) and its most severe form, the acute respiratory distress syndrome (ARDS), lung microvessel endothelia lose their junctional integrity resulting in leakiness of the endothelial barrier and accumulation of protein rich edema. Increased reactive oxygen species (ROS) generated by neutrophils (PMNs) and other inflammatory cells play an important role in increasing endothelial permeability. In essence, multiple inflammatory syndromes are caused by dysfunction and compromise of the barrier properties of the endothelium as a consequence of unregulated acute inflammatory response. This review focuses on the role of ROS signaling in controlling endothelial permeability with particular focus on ALI. We summarize below recent progress in defining signaling events leading to increased endothelial permeability and ALI. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Chemisorption on size-selected metal clusters: activation barriers and chemical reactions for deuterium and aluminum cluster ions

    International Nuclear Information System (INIS)

    Jarrold, M.F.; Bower, J.E.

    1988-01-01

    The authors describe a new approach to investigating chemisorption on size-selected metal clusters. This approach involves investigating the collision-energy dependence of chemisorption using low-energy ion beam techniques. The method provides a direct measure of the activation barrier for chemisorption and in some cases an estimate of the desorption energy as well. They describe the application of this technique to chemisorption of deuterium on size-selected aluminum clusters. The activation barriers increase with cluster size (from a little over 1 eV for Al 10 + to around 2 eV for Al 27 + ) and show significant odd-even oscillations. The activation barriers for the clusters with an odd number of atoms are larger than those for the even-numbered clusters. In addition to chemisorption of deuterium onto the clusters, chemical reactions were observed, often resulting in cluster fragmentation. The main products observed were Al/sub n-1/D + , Al/sub n-2/ + , and Al + for clusters with n + and Al/sub n-1/D + for the larger clusters

  10. Energy efficiency and barriers towards meeting energy demand in industries in Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Unachukwu, Godwin O.; Zarma, I.H.; Sambo, A.S.

    2010-09-15

    Energy is an important production factor and therefore should be managed in parallel with land, labor and capital. Energy efficient production should be seen as a quick and cheaper source of new energy supply as the cost of providing energy can be several times the cost of saving it. Increasingly energy efficiency is deemed to include not only the physical efficiency of the technical equipment and facilities but also the overall economic efficiency of the energy system.

  11. Energy efficiency in social housing: Opportunities and barriers from a case study in Brazil

    International Nuclear Information System (INIS)

    Bodach, Susanne; Hamhaber, J.

    2010-01-01

    This paper investigates the energy efficiency in a segment of the building sector in emerging countries by analyzing and evaluating the energy efficiency of a social housing project in Brazil. Energy efficiency measures and bioclimatic design strategies are developed in order to improve thermal comfort in this social housing project and to reduce the energy consumption and expenses of their residents. The institutional barriers and constraints toward higher efficiency are described. The results of this study show that there is a high potential to increase energy efficiency in social housing in emerging countries like Brazil. The implementation and consideration of the energy efficiency measures and policy recommendations would contribute substantially to the goal to dampen the fast growth of energy demand in these countries. Moreover the improvement of energy efficiency in the social housing sector could be a driver for market transformation towards more sustainability in the whole building sector. - Research highlights: →There is a high potential to increase energy efficiency in social housing in Brazil. →Energy-efficient social housing would contribute substantially to dampen the fast growth of energy consumption in emerging countries like Brazil. →Implementation of energy efficiency would improve the income situation of the poorest strata of the population.

  12. Desmoglein 2 regulates the intestinal epithelial barrier via p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Ungewiß, Hanna; Vielmuth, Franziska; Suzuki, Shintaro T; Maiser, Andreas; Harz, Hartmann; Leonhardt, Heinrich; Kugelmann, Daniela; Schlegel, Nicolas; Waschke, Jens

    2017-07-24

    Intestinal epithelial barrier properties are maintained by a junctional complex consisting of tight junctions (TJ), adherens junctions (AJ) and desmosomes. Desmoglein 2 (Dsg2), an adhesion molecule of desmosomes and the only Dsg isoform expressed in enterocytes, is required for epithelial barrier properties and may contribute to barrier defects in Crohn's disease. Here, we identified extradesmosomal Dsg2 on the surface of polarized enterocytes by Triton extraction, confocal microscopy, SIM and STED. Atomic force microscopy (AFM) revealed Dsg2-specific binding events along the cell border on the surface of enterocytes with a mean unbinding force of around 30pN. Binding events were blocked by an inhibitory antibody targeting Dsg2 which under same conditions activated p38MAPK but did not reduce cell cohesion. In enterocytes deficient for Dsg2, p38MAPK activity was reduced and both barrier integrity and reformation were impaired. Dsc2 rescue did not restore p38MAPK activity indicating that Dsg2 is required. Accordingly, direct activation of p38MAPK in Dsg2-deficient cells enhanced barrier reformation demonstrating that Dsg2-mediated activation of p38MAPK is crucial for barrier function. Collectively, our data show that Dsg2, beside its adhesion function, regulates intestinal barrier function via p38MAPK signalling. This is in contrast to keratinocytes and points towards tissue-specific signalling functions of desmosomal cadherins.

  13. Barriers related to physical activity practice in adolescents. A focus-group study

    Directory of Open Access Journals (Sweden)

    Ciro Romélio Rodriguez Añez

    2010-04-01

    Full Text Available The aim of study was to identify barriers to physical activity in adolescents. Focus group interviews were conducted with subjects aged 15 to 18 years (n=59, 50.8% girls and divided according to gender. Content analysis was used to classify the reports into specific dimensions. Descriptive statistics employing relative and absolute frequencies of similar reports was performed using the SPSS 11.0 software. The most frequent barriers among adolescents were those associated with “psychological, cognitive and emotional” and “cultural and social” dimensions. For boys, the most frequently reported barriers were “feeling lazy”, “lack of company” and “lack of time”. For girls, “feeling lazy”, “lack of com-pany” and “occupation” were the most common barriers. In conclusion, the perception of barriers by adolescents varies according to gender, a fact requiring specific actions for the promotion of physical activity in this group.

  14. Observation of the one- to six-neutron transfer reactions at sub-barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, C.L.; Rehm, K.E.; Gehring, J. [and others

    1995-08-01

    It was suggested many years ago that when two heavy nuclei are in contact during a grazing collision, the transfer of several correlated neutron-pairs could occur. Despite considerable experimental effort, however, so far only cross sections for up to four-neutron transfers have been uniquely identified. The main difficulties in the study of multi-neutron transfer reactions are the small cross sections encountered at incident energies close to the barrier, and various experimental uncertainties which can complicate the analysis of these reactions. We have for the first time found evidence for multi-neutron transfer reactions covering the full sequence from one- to six-neutron transfer reactions at sub-barrier energies in the system {sup 58}Ni + {sup 100}Mo.

  15. What are the barriers and incentives for community-owned means of energy production and use?

    International Nuclear Information System (INIS)

    Walker, Gordon

    2008-01-01

    This paper on community-owned means of renewable energy production and use, reviews experience to date in the UK and the incentives for and barriers limiting current and future growth. A broad view is taken of what the meaning of 'community-owned production and use' might constitute, as there are different models of community ownership, different notions of community and different degrees of connection or disconnection between production and use

  16. Fusion of light ion systems at energies near and below the Coulomb barrier

    International Nuclear Information System (INIS)

    Arnould, M.; Howard, W.M.; Cusson, R.Y.

    1978-01-01

    Experimental fusion cross sections for light ion systems at energies below the Coulomb barrier become available in greater and greater number, and provide a stringent test of the macroscopic and microscopic physics involved in models of heavy-ion reactions. Measurements and predictions of the fusion cross sections for 12 C + 12 C, 12 C + 16 O and 16 O + 16 O are also of major importance in astrophysics. (orig.) [de

  17. Simulations of Skin Barrier Function: Free Energies of Hydrophobic and Hydrophilic Transmembrane Pores in Ceramide Bilayers

    OpenAIRE

    Notman, Rebecca; Anwar, Jamshed; Briels, W. J.; Noro, Massimo G.; den Otter, Wouter K.

    2008-01-01

    Transmembrane pore formation is central to many biological processes such as ion transport, cell fusion, and viral infection. Furthermore, pore formation in the ceramide bilayers of the stratum corneum may be an important mechanism by which penetration enhancers such as dimethylsulfoxide (DMSO) weaken the barrier function of the skin. We have used the potential of mean constraint force (PMCF) method to calculate the free energy of pore formation in ceramide bilayers in both the innate gel pha...

  18. Negotiating EU CO2/energy taxation. Political economic driving forces and barriers

    International Nuclear Information System (INIS)

    Klok, Jacob

    2001-11-01

    The primary objective of this project is to identify the main political economic driving forces behind and barriers against the creation of an EU agreement on CO 2 /energy taxation. The analysis is based on a theoretical framework for understanding European integration and on detailed historical investigations into a process of EU negotiations concerning CO 2 /energy taxation that took place from the 1980s to 1994. Following the historical analysis of political economic driving forces and barriers, some overall perspectives on possible future developments within the field of EU CO 2 /energy taxation are finally advanced. The secondary objective of the project is to consider the possible effects on the EU negotiation process of Danish efforts to push the CO 2 /energy tax proposal from the late 1980s to 994. This analysis is based on the preceding historical analysis of the EU negotiation process, as well as further investigations into the national Danish development within the field of CO 2 /energy taxation, including accounts of Denmark's particular relations with the EU during the period in question. Finally, based on the likely future developments in the field EU CO 2 /energy taxation. Denmark's strategic opportunities are outlined. (BA)

  19. Financing energy SMEs in Ghana and Senegal: Outcomes, barriers and prospects

    International Nuclear Information System (INIS)

    Haselip, James; Desgain, Denis; Mackenzie, Gordon

    2014-01-01

    The article presents the findings of primary research carried out in Ghana and Senegal, which revisited the main assumptions behind the African Rural Energy Enterprise Development (AREED) initiative (2002–2012), and other donor-backed programmes, designed to promote small and medium-sized energy enterprises (energy SMEs). These assumptions were (1) that the lack of affordable local financing presented the most significant barrier to setting up and expanding energy SMEs, and (2) that these barriers would be overcome by a ‘demonstration effect’ whereby successful businesses, supported by donor-backed programmes, could in turn influence the commercial financial sector to invest in energy SMEs, thus triggering a virtuous circle of growth and profitability. - Highlights: • Analysis of the AREED ‘demonstration effect’ in Senegal and Ghana. • Commercial financial backing for SMEs remains a serious challenge for entrepreneurs. • Structural issues that increase the financial risk of investing in energy SMEs. • High transaction costs of investing in SMEs. • Longer supply chains and slower pay-back periods for capital-intensive technologies

  20. Capabilities of silicon Shottki barriers and planar detectors in low-energy proton spectometry

    Energy Technology Data Exchange (ETDEWEB)

    Verbitskaya, E M; Eremin, V K; Malyarenko, A M; Sakharov, V I; Serenkov, I T; Strokan, N B; Sukhanov, V L

    1987-05-12

    Dependence of the resolution of surface barrier and planar diffusion silicon detectors on proton energy is investigated. The experiment was conducted at the device, representing the double mass spectrometer with the maximal energy of single-charged ions up to 200 keV. Two advantages of using planar diffusion detectors for light low-energy ion spectrometry is established: high energy resolution and independence of signal amplitude of bias voltage. Background noise represents the main factor dictaiting resolution, but fluctuations of losses in input window are sufficient as well. It was concluded that planar detector application for spectrometry of protons with energy of less than 200 keV would improve the resolution up to 2.2 keV without detector cooling.

  1. Attitudes, barriers and enablers to physical activity in pregnant women: a systematic review

    Directory of Open Access Journals (Sweden)

    Anne L Harrison

    2018-01-01

    Registration: PROSPERO CRD42016037643. [Harrison AL, Taylor NF, Shields N, Frawley HC (2018 Attitudes, barriers and enablers to physical activity in pregnant women: a systematic review. Journal of Physiotherapy 64: 24–32

  2. Perceived Barriers to Healthy Eating and Physical Activity Among Participants in a Workplace Obesity Intervention.

    Science.gov (United States)

    Stankevitz, Kayla; Dement, John; Schoenfisch, Ashley; Joyner, Julie; Clancy, Shayna M; Stroo, Marissa; Østbye, Truls

    2017-08-01

    To characterize barriers to healthy eating (BHE) and physical activity (BPA) among participants in a workplace weight management intervention. Steps to health participants completed a questionnaire to ascertain barriers to physical activity and healthy eating faced. Exploratory factor analysis was used to determine the factor structure for BPA and BHE. The relationships of these factors with accelerometer data and dietary behaviors were assessed using linear regression. Barriers to physical activity included time constraints and lack of interest and motivation, and to healthy eating, lack of self-control and convenience, and lack of access to healthy foods. Higher BHE correlated with higher sugary beverage intake but not fruit and vegetable and fat intake. To improve their effectiveness, workplace weight management programs should consider addressing and reducing barriers to healthy eating and physical activity.

  3. Motivational readiness for active commuting by university students: incentives and barriers.

    Science.gov (United States)

    Cole, Rachel; Leslie, Eva; Donald, Maria; Cerin, Ester; Neller, Anne; Owen, Neville

    2008-12-01

    Walking for transport can contribute significantly to health-enhancing physical activity. We examined the associations of stages of motivational readiness for active transport with perceived barriers and incentives to walking to and from university among students. Mail-back surveys were completed by 781 students in a regional university in south-east Queensland. They identified one of eight options on motivational readiness for active commuting, which were then classified as: pre-contemplation; contemplation-preparation; or, action-maintenance. Open-ended questions were used to identify relevant barriers and incentives. Logistic regressions were used to examine the barriers and incentives that distinguished between those at different stages of motivational readiness. Barriers most frequently reported were long travel distances, inconvenience and time constraints. Incentives most frequently reported were shorter travel distance, having more time, supportive infrastructure and better security. Those not considering active commuting (pre-contemplation) were significantly more likely to report shorter travel distance as an incentive compared to those in contemplation-preparation. Those in contemplation-preparation were significantly more likely to report lack of motivation, inadequate infrastructure, shorter travel distance and inconvenience as barriers; and, having more time, supportive infrastructure, social support and incentive programs as encouragement. Different barriers and incentives to walking to or from university exist for students in the different stages of motivational readiness for active commuting. Interventions targeted specifically to stage of motivational readiness may be potentially helpful in increasing activity levels, through active transport.

  4. Barriers on the propagation of renewable energy sources and sustainable solid waste management practices in Greece.

    Science.gov (United States)

    Boemi, Sn; Papadopoulos, Am; Karagiannidis, A; Kontogianni, S

    2010-11-01

    Renewable energy sources (RES), excluding large hydroelectric plants, currently produce 4.21% of total electricity production in Greece. Even when considering the additional production from large hydroelectric plants, which accounts for some 7.8%, the distance to be covered towards the objective of 20% electricity produced from RES by 2010 and respectively towards 20% of total energy production by 2020 is discouraging. The potential, however, does exist; unfortunately so do serious barriers. On the other hand, solid waste management (SWM) is an issue that generates continuously increasing interest due to the extra amounts of solid waste generated; the lack of existing disposal facilities with adequate infrastructure and integrated management plans, also often accompanied by legislative and institutional gaps. However, socio-economic and public awareness problems are still met in the planning and implementation of RES and SWM projects, together with the lack of a complete national cadastre and a spatial development master plan, specifying areas eligible for RES and SWM development. Specific barriers occur for individual RES and the on-going inclusion of waste-derived renewable energy in the examined palette further increases the complexity of the entire issue. The consolidated study of this broad set of barriers was a main task of the present study which was carried out within the frame of a Hellenic-Canadian research project; the main results will be discussed herein.

  5. Simulations of skin barrier function: free energies of hydrophobic and hydrophilic transmembrane pores in ceramide bilayers.

    Science.gov (United States)

    Notman, Rebecca; Anwar, Jamshed; Briels, W J; Noro, Massimo G; den Otter, Wouter K

    2008-11-15

    Transmembrane pore formation is central to many biological processes such as ion transport, cell fusion, and viral infection. Furthermore, pore formation in the ceramide bilayers of the stratum corneum may be an important mechanism by which penetration enhancers such as dimethylsulfoxide (DMSO) weaken the barrier function of the skin. We have used the potential of mean constraint force (PMCF) method to calculate the free energy of pore formation in ceramide bilayers in both the innate gel phase and in the DMSO-induced fluidized state. Our simulations show that the fluid phase bilayers form archetypal water-filled hydrophilic pores similar to those observed in phospholipid bilayers. In contrast, the rigid gel-phase bilayers develop hydrophobic pores. At the relatively small pore diameters studied here, the hydrophobic pores are empty rather than filled with bulk water, suggesting that they do not compromise the barrier function of ceramide membranes. A phenomenological analysis suggests that these vapor pores are stable, below a critical radius, because the penalty of creating water-vapor and tail-vapor interfaces is lower than that of directly exposing the strongly hydrophobic tails to water. The PMCF free energy profile of the vapor pore supports this analysis. The simulations indicate that high DMSO concentrations drastically impair the barrier function of the skin by strongly reducing the free energy required for pore opening.

  6. Barriers and Potential Solutions for Energy Renovation of Buildings in Denmark

    Directory of Open Access Journals (Sweden)

    Niels I. Meyer

    2014-02-01

    Full Text Available Buildings account for a substantial part of the total energy consumption. In Denmark this number is about 40 % and this is approximately the same in most industrial countries. On this background there is an urgent need to develop strategies for reducing the energy demand in the building sector. Renovation of existing buildings must have high priority as houses often last for 50 to 100 years, while the time perspective for the desired transformation to low-energy houses is less than 30 years in order to mitigate global warming and avoid irreversible tipping-points. The only sustainable energy supply in the perspective of centuries is renewable energy provided by the sun and exploited in the form of solar heat, solar electricity (PVs, wind power, hydropower, wave power, and some types of biomass etc. A future dominating role of intermittent renewable sources requires new integrated systems thinking on both the supply and demand side for heat, electricity and transport. Implementing such Smart Energy Systems requires integrated strategic energy planning on the national and local level. With the fundamental changes in the energy supply technologies expected during the coming years, it is important to synchronize investments in energy conservation measures with investments in the supply side, in order to avoid overinvestment in supply systems and thus to minimize the total costs of the transformation to Smart Energy Systems. This paper highlights some of the most important barriers for renovation of existing buildings in Denmark and points to policies for overcoming these barriers. Some of the policies have been presented in the reports of a recent Danish research project (CEESA

  7. Perceived barriers to leisure-time physical activity and associated factors in adolescents.

    Science.gov (United States)

    Dias, Douglas Fernando; Loch, Mathias Roberto; Ronque, Enio Ricardo Vaz

    2015-11-01

    The objective of this study was to identify the prevalence of perceived barriers to leisure-time physical activity in teenagers and to examine the possible association of these barriers with leisure-time physical inactivity. This cross-sectional study was conducted in 2011 and a representative sample of 1,409 high school students from public schools in the city of Londrina/Paraná was selected through multistage sampling. For data collection, the adolescents completed a questionnaire. The relationship between leisure-time physical inactivity (barriers was analyzed by calculating the prevalence ratio (PR) in Poisson regression models. "Lack of friends company" was the most prevalent barrier for both girls (75.8%) and boys (58.7%). "Feel lazy" for girls (PR: 1.21; CI 95%: 1.08 to 1.36) and "prefer to do other things" for the boys (PR: 1.48; CI 95%: 1.01 to 2.15) were the barriers most strongly associated with leisure-time physical inactivity. For both genders, a strong dose-response relationship was observed between the number of perceived barriers and leisure-time physical inactivity. The perception of barriers was associated with a higher prevalence of leisure-time physical inactivity in adolescents and should therefore be considered in actions for promoting physical activity in this population.The objective of this study was to identify the prevalence of perceived barriers to leisure-time physical activity in teenagers and to examine the possible association of these barriers with leisure-time physical inactivity. This cross-sectional study was conducted in 2011 and a representative sample of 1,409 high school students from public schools in the city of Londrina/Paraná was selected through multistage sampling. For data collection, the adolescents completed a questionnaire. The relationship between leisure-time physical inactivity (barriers was analyzed by calculating the prevalence ratio (PR) in Poisson regression models. "Lack of friends company" was the most

  8. Barriers to participation in physical activity and exercise among middle-aged and elderly individuals.

    Science.gov (United States)

    Justine, Maria; Azizan, Azliyana; Hassan, Vaharli; Salleh, Zoolfaiz; Manaf, Haidzir

    2013-10-01

    INTRODUCTION Although the benefits of physical activity and exercise are widely acknowledged, many middle-aged and elderly individuals remain sedentary. This cross-sectional study aimed to identify the external and internal barriers to physical activity and exercise participation among middle-aged and elderly individuals, as well as identify any differences in these barriers between the two groups. METHODS Recruited individuals were categorised into either the middle-aged (age 45-59 years, n = 60) or elderly (age ≥ 60 years, n = 60) group. Data on demographics, anthropometry, as well as external and internal barriers to participation in physical activity and exercise were collected. RESULTS Analysis showed no significant differences in the total scores of all internal barriers between the two groups (p > 0.05). The total scores for most external barriers between the two groups also showed no significant differences (p > 0.05); only 'cost' (p = 0.045) and 'exercise interferes with social/family activities' (p = 0.011) showed significant differences. The most common external barriers among the middle-aged and elderly respondents were 'not enough time' (46.7% vs. 48.4%), 'no one to exercise with' (40.0% vs. 28.3%) and 'lack of facilities' (33.4% vs. 35.0%). The most common internal barriers for middle-aged respondents were 'too tired' (48.3%), 'already active enough' (38.3%), 'do not know how to do it' (36.7%) and 'too lazy' (36.7%), while those for elderly respondents were 'too tired' (51.7%), 'lack of motivation' (38.4%) and 'already active enough' (38.4%). CONCLUSION Middle-aged and elderly respondents presented with similar external and internal barriers to physical activity and exercise participation. These factors should be taken into account when healthcare policies are being designed and when interventions such as the provision of facilities to promote physical activity and exercise among older people are being considered.

  9. Tunneling of an energy eigenstate through a parabolic barrier viewed from Wigner phase space

    DEFF Research Database (Denmark)

    Heim, D.M.; Schleich, W.P.; Alsing, P.M.

    2013-01-01

    We analyze the tunneling of a particle through a repulsive potential resulting from an inverted harmonic oscillator in the quantum mechanical phase space described by the Wigner function. In particular, we solve the partial differential equations in phase space determining the Wigner function...... of an energy eigenstate of the inverted oscillator. The reflection or transmission coefficients R or T are then given by the total weight of all classical phase-space trajectories corresponding to energies below, or above the top of the barrier given by the Wigner function....

  10. Liquid-drop model description of heavy ion fusion at sub-barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, C E; Barbosa, V C; Canto, L F; Donangelo, R

    1987-10-05

    The enhancement of the heavy ion fusion cross section at sub-barrier energies is studied in the liquid-drop model approach. The shape of the system is described by two spheres smoothly connected by a neck, and the kinetic and potential energies are calculated within this parametrization. Underbarrier fusion cross sections for symmetric projectile-target combinations are calculated in the WKB approximation and a comparison with the available data is made. The agreement is quite satisfactory, except for those systems in which the reaction is strongly affected by the details of the nuclear structure of the collision partners.

  11. Complex energy eigenvalues of a linear potential with a parabolical barrier

    International Nuclear Information System (INIS)

    Malherbe, J.B.

    1978-01-01

    The physical meaning and restrictions of complex energy eigenvalues are briefly discussed. It is indicated that a quasi-stationary phase describes an idealised disintegration system. Approximate resonance-eigenvalues of the one dimensional Schrodinger equation with a linear potential and parabolic barrier are calculated by means of Connor's semiclassical method. This method is based on the generalized WKB-method of Miller and Good. The results obtained confirm the correctness of a model representation which explains the unusual distribution of eigenvalues by certain other linear potentials in a complex energy level [af

  12. Polymer in a pore: Effect of confinement on the free energy barrier

    Science.gov (United States)

    Kumar, Sanjiv; Kumar, Sanjay

    2018-06-01

    We investigate the transfer of a polymer chain from cis- side to trans- side through two types of pores: cone-shaped channel and flat-channel. Using the exact enumeration technique, we obtain the free energy landscapes of a polymer chain for such systems. We have also calculated the free-energy barrier of a polymer chain attached to the edge of the pore. The model system allows us to calculate the force required to pull polymer from the pore and stall-force to confine polymer within the pore.

  13. Reduction of the energy of secondary beams down to the Coulomb barrier

    International Nuclear Information System (INIS)

    Yang Yong Feng; Mittig, W.; Roussel-Chomaz, P.; Lewitowicz, M.; Sida, J.L.; Alamanos, N.; Auger, F.; Gillibert, A.; Volant, C.; Cabot, C.; Borcea, C.

    1993-01-01

    With the doubly achromatic spectrometer LISE at GANIL, the energy of a secondary 11 Be beam produced by the reaction of 63 MeV/nucleon 18 O with a 9 Be target has been reduced to Coulomb barrier energies using various thick targets and a thinner target plus a thick degrader. The experimental results were compared with calculations performed with the program INTENSITY and with simple analytical expressions. It was found that in the present device, the thick target method is more convenient and efficient than the achromatic degrader

  14. Micro-fabricated Liquid Encapsulated Energy Harvester with Polymer Barrier Layer as Liquid Electret Interface

    International Nuclear Information System (INIS)

    Bu, L; Xu, H Y; Xu, B J; Song, L

    2014-01-01

    This paper addresses the electret discharge issue for liquid based electret energy harvesters. An interface structure of PDMS/PTFE polymer barrier layer between liquid and electrets is introduced, achieving 75% charge retain rate over 100h, compared with 0% without the proposed layer over 100h. Further, the PDMS/PTFE layer is introduced into liquid encapsulated energy harvester (LEEH) and is compatible with micro-fabrication process. The retain rate of device voltage is about 47%∼65% over 100h. At 100h after corona charging, the device generates maximally 3.7V, 0.55μW @1Hz rotation

  15. Barriers to retail marketing of renewable energy products in an energy-rich province

    International Nuclear Information System (INIS)

    Haner, S.A.

    1999-01-01

    Personal experiences in attempting to market photovoltaics and other renewable energy products in Alberta, a province rich in energy sources, are recounted as part of an exploration of ways to help industry to develop strategies that will advance the acceptance of renewable energy products, particularly in areas of the world that are not concerned about energy supply. Social acceptability, emphasis on a healthy and convenient lifestyle associated with renewable energy products, practical, user-friendly products, and competitive prices, are some of the key elements in successfully marketing renewable energy products

  16. Oxygen plasma etching of graphene: A first-principles dynamical inspection of the reaction mechanisms and related activation barriers

    Science.gov (United States)

    Koizumi, Kenichi; Boero, Mauro; Shigeta, Yasuteru; Oshiyama, Atsushi; Dept. of Applied Physics Team; Institute of Physics and Chemistry of Strasbourg (IPCMS) Collaboration; Department Of Materials Engineering Science Collaboration

    2013-03-01

    Oxygen plasma etching is a crucial step in the fabrication of electronic circuits and has recently received a renovated interest in view of the realization of carbon-based nanodevices. In an attempt at unraveling the atomic-scale details and to provide guidelines for the control of the etching processes mechanisms, we inspected the possible reaction pathways via reactive first principles simulations. These processes involve breaking and formation of several chemical bonds and are characterized by different free-energy barriers. Free-energy sampling techniques (metadynamics and blue moon), used to enhance the standard Car-Parrinello molecular dynamics, provide us a detailed microscopic picture of the etching of graphene surfaces and a comprehensive scenario of the activation barriers involved in the various steps. MEXT, Japan - contract N. 22104005

  17. Efficient sampling over rough energy landscapes with high barriers: A combination of metadynamics with integrated tempering sampling

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y. Isaac [Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Zhang, Jun; Che, Xing; Yang, Lijiang; Gao, Yi Qin, E-mail: gaoyq@pku.edu.cn [Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Biodynamic Optical Imaging Center, Peking University, Beijing 100871 (China)

    2016-03-07

    In order to efficiently overcome high free energy barriers embedded in a complex energy landscape and calculate overall thermodynamics properties using molecular dynamics simulations, we developed and implemented a sampling strategy by combining the metadynamics with (selective) integrated tempering sampling (ITS/SITS) method. The dominant local minima on the potential energy surface (PES) are partially exalted by accumulating history-dependent potentials as in metadynamics, and the sampling over the entire PES is further enhanced by ITS/SITS. With this hybrid method, the simulated system can be rapidly driven across the dominant barrier along selected collective coordinates. Then, ITS/SITS ensures a fast convergence of the sampling over the entire PES and an efficient calculation of the overall thermodynamic properties of the simulation system. To test the accuracy and efficiency of this method, we first benchmarked this method in the calculation of ϕ − ψ distribution of alanine dipeptide in explicit solvent. We further applied it to examine the design of template molecules for aromatic meta-C—H activation in solutions and investigate solution conformations of the nonapeptide Bradykinin involving slow cis-trans isomerizations of three proline residues.

  18. Measurement of leakage and design for the protective barrier of the high energy radiation therapy room

    International Nuclear Information System (INIS)

    Chu, S.S.; Park, C.Y.

    1981-01-01

    The logical development of an optimum structural shielding design and the computation of protective barriers for high energy radiation therapy room, Toshiba 13 MeV are presented. We obtained following results by comparison in between the precalculating values and actual survey after complete installation of radiogenerating units. 1) The calculating formula for the protective barrier written in NCRP report no. 34(1970) was the most ideal and economic calculating methods for the construction of barrier and to determine thickness for the meeting requirements of the number of patients of 80-100 in daily treatment. 2) The precalculating values of protective barrier are 5 times more protective than that of actual measurement. It is depending on radiation workload and utilization the data most securely. 3) The dose rate during exposure are 2-10 mR/hr at out of the door and the control room. 4) The foul smelling and ozone gas production from long exposure of cancer patients cannot be estimated when the room is ill ventilated. (author)

  19. Renewable energy in South Africa. Potentials, barriers and options for support

    Energy Technology Data Exchange (ETDEWEB)

    Pegels, Anna [German Development Institute/Deutsches Institut fuer Entwicklungspolitik, Tulpenfeld 6, 53113 Bonn (Germany)

    2010-09-15

    The challenge of transforming entire economies is enormous; even more so if a country is as fossil fuel based and emission intensive as South Africa. However, in an increasingly carbon constrained world and already now facing climate change impacts South Africa has to reduce greenhouse gas emissions intensity soon and decidedly. The South African electricity sector is a vital part of the economy and at the same time contributes most to the emissions problem. First steps have been taken by the South African government to enhance energy efficiency and promote renewable energy, however, they fail to show large-scale effects. This paper seeks to identify the relevant barriers to renewable energy investments and, based on experience from other countries, provide policy recommendations. The major barrier identified in the paper is based on the economics of renewable energy technologies, i.e. their cost and risk structures, two main factors in investment planning. As a solution, the South African government introduced several renewable energy support measures, such as a feed-in tariff. The paper discusses the potential and possible shortcomings of this and other existing support schemes and identifies complementing measures on a national scale. (author)

  20. Renewable energy in South Africa: Potentials, barriers and options for support

    Energy Technology Data Exchange (ETDEWEB)

    Pegels, Anna, E-mail: anna.pegels@die-gdi.d [German Development Institute/Deutsches Institut fuer Entwicklungspolitik, Tulpenfeld 6, 53113 Bonn (Germany)

    2010-09-15

    The challenge of transforming entire economies is enormous; even more so if a country is as fossil fuel based and emission intensive as South Africa. However, in an increasingly carbon constrained world and already now facing climate change impacts South Africa has to reduce greenhouse gas emissions intensity soon and decidedly. The South African electricity sector is a vital part of the economy and at the same time contributes most to the emissions problem. First steps have been taken by the South African government to enhance energy efficiency and promote renewable energy, however, they fail to show large-scale effects. This paper seeks to identify the relevant barriers to renewable energy investments and, based on experience from other countries, provide policy recommendations. The major barrier identified in the paper is based on the economics of renewable energy technologies, i.e. their cost and risk structures, two main factors in investment planning. As a solution, the South African government introduced several renewable energy support measures, such as a feed-in tariff. The paper discusses the potential and possible shortcomings of this and other existing support schemes and identifies complementing measures on a national scale.

  1. Modeling barriers of solid waste to energy practices: An Indian perspective

    International Nuclear Information System (INIS)

    Bag, S.; Mondal, N.; Dubey, R.

    2016-01-01

    In recent years managing solid wastes has been one of the burning problems in front of state and local municipal authorities. This is mainly due to scarcity of lands for landfill sites. In this context experts suggest that conversion of solid waste to energy and useful component is the best approach to reduce space and public health related problems. The entire process has to be managed by technologies that prevent pollution and protect the environment and at the same time minimize the cost through recovery of energy. Energy recovery in the form of electricity, heat and fuel from the waste using different technologies is possible through a variety of processes, including incineration, gasification, pyrolysis and anaerobic digestion. These processes are often grouped under “Waste to Energy technologies”. The objective of the study is twofold. First authors assessed the current status of solid waste management practices in India. Secondly the leading barriers are identified and Interpretive structural modeling technique and MICMAC analysis is performed to identify the contextual interrelationships between leading barriers influencing the solid waste to energy programs in the country. Finally the conclusions are drawn which will assist policy makers in designing sustainable waste management programs.

  2. Renewable energy in South Africa: Potentials, barriers and options for support

    International Nuclear Information System (INIS)

    Pegels, Anna

    2010-01-01

    The challenge of transforming entire economies is enormous; even more so if a country is as fossil fuel based and emission intensive as South Africa. However, in an increasingly carbon constrained world and already now facing climate change impacts South Africa has to reduce greenhouse gas emissions intensity soon and decidedly. The South African electricity sector is a vital part of the economy and at the same time contributes most to the emissions problem. First steps have been taken by the South African government to enhance energy efficiency and promote renewable energy, however, they fail to show large-scale effects. This paper seeks to identify the relevant barriers to renewable energy investments and, based on experience from other countries, provide policy recommendations. The major barrier identified in the paper is based on the economics of renewable energy technologies, i.e. their cost and risk structures, two main factors in investment planning. As a solution, the South African government introduced several renewable energy support measures, such as a feed-in tariff. The paper discusses the potential and possible shortcomings of this and other existing support schemes and identifies complementing measures on a national scale.

  3. Energy barrier of bcc-fcc phase transition via the Bain path in Yukawa system

    Science.gov (United States)

    Kiyokawa, Shuji

    2018-05-01

    In the Yukawa system with the dimensionless screening parameter κ>1.5 , when bcc-fcc transition occurs via Bain path, we show that spontaneous transitions do not occur even if the system temperature reaches the transition point of bcc-fcc because it is necessary to increase once the free energy in the process of transition from bcc to fcc through Bain deformation. Here, we refer the temporary increment of the free energy during Bain deformation as Bain barrier. Since there are the Bain barriers at the transitions between bcc and fcc phases, these phases may coexist as metastable state in the wide region (not a coexistence line) of κ and the coupling constant Γ. We study the excess energy of the system and the free energy difference between bcc and fcc phases by the Monte Carlo method, where the simulation box is divided into a large number of elements with small volume and a particle in the box is restricted be placed in one of these elements. By this method, we can tabulate the values of the interparticle potential and can calculate the internal energy fast and precisely.

  4. Final report. Renewable energy and energy efficiency in Mexico: Barriers and opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Ashford, Mike

    2000-09-28

    The report describes the prospects for energy efficiency and greenhouse gas emissions reductions in Mexico, along with renewable energy potential. A methodology for developing emissions baselines is shown, in order to prepare project emissions reductions calculations. An application to the USIJI program was also prepared through this project, for a portfolio of energy efficiency projects.

  5. Physical Activity Correlates in Middle School Adolescents: Perceived Benefits and Barriers and Their Determinants.

    Science.gov (United States)

    Roth, Sarah E; Gill, Monique; Chan-Golston, Alec M; Rice, Lindsay N; Crespi, Catherine M; Koniak-Griffin, Deborah; Cole, Brian L; Upchurch, Dawn M; Prelip, Michael L

    2018-01-01

    The purpose of this study was to examine the determinants of benefits and barriers and their relationship with physical activity (PA) among predominantly Latino middle school students. Data were collected in a cross-sectional survey of 4,773 seventh-grade students recruited from a large, urban school district in Los Angeles. Hierarchical logistic regression models were used to assess determinants of benefits and barriers as well as their association with self-reported PA. Differences in benefits and barriers were observed by gender, ethnicity, and body size. Barriers were negatively correlated with all three PA outcomes while benefits were positively associated with exercising at least 60 min daily. A deeper understanding of benefits and barriers can facilitate the development of interventions and collaborative efforts among physical education teachers, school nurses, and administrators to implement comprehensive approaches that encourage students' participation in PA inside and outside of the classroom.

  6. Fusion hindrance at deep sub-barrier energies for the 11B+197Au system

    Science.gov (United States)

    Shrivastava, A.; Mahata, K.; Nanal, V.; Pandit, S. K.; Parkar, V. V.; Rout, P. C.; Dokania, N.; Ramachandran, K.; Kumar, A.; Chatterjee, A.; Kailas, S.

    2017-09-01

    Fusion cross sections for the 11B+197Au system have been measured at energies around and deep below the Coulomb barrier, to probe the occurrence of fusion hindrance in case of asymmetric systems. A deviation with respect to the standard coupled channels calculations has been observed at the lowest energy. The results have been compared with an adiabatic model calculation that considers a damping of the coupling strength for a gradual transition from sudden to adiabatic regime at very low energies. The data could be explained without inclusion of the damping factor. This implies that the influence of fusion hindrance is not significant within the measured energy range for this system. The present result is consistent with the observed trend between the degree of fusion hindrance and the charge product that reveals a weaker influence of hindrance on fusion involving lighter projectiles on heavy targets.

  7. Barriers and Facilitators of Physical Activity in Children of a South Asian Ethnicity

    Directory of Open Access Journals (Sweden)

    Lee Smith

    2018-03-01

    Full Text Available Children of South Asian ethnicity residing in England have low levels of physical activity. Limited literature exists on correlates, barriers, and facilitators to activity in South Asian children. The aim of this study was to fill this gap in the literature. Interviews were conducted with 10 parents of South Asian ethnicity residing in the UK. Interviews covered a description of the family setup, participants’ opinions of physical activity including barriers and facilitators and their children’s participation, as well as approaches to general parenting, and how children spend their free time. Data were analysed using thematic analysis. Key themes identified included (i restraints on parents’ and children’s time to be physically active; (ii the role of the family in children’s physical activity participation; (iii situational barriers to physical activity; (iv physical activity not a priority; (v opportunities to be active; and (vi perception of activity level and health. A number of key barriers to South Asian children’s participation in physical activity were identified, including (i restraints on parents and children’s time; (ii parents providing limited support for physical activity; and (iii physical activity having a low priority. A number of facilitators were also identified (i play; (ii school-time; and (iii extra-curricular clubs. In this sample of South Asian parents residing in the UK several socio-cultural barriers and facilitators of their children’s physical activity have been identified. The study provides preliminary data for a larger study to ascertain if such barriers and facilitators are representative of the wider South Asian community, so that recommendations for intervention and policies can be made.

  8. Municipal Officials’ Perceived Barriers to Consideration of Physical Activity in Community Design Decision Making

    Science.gov (United States)

    Goins, Karin Valentine; Schneider, Kristin L.; Brownson, Ross; Carnoske, Cheryl; Evenson, Kelly; Eyler, Amy; Heinrich, Katie; Litt, Jill; Lyn, Rodney; Maddock, Jay; Reed, Hannah; Tompkins, Nancy O’Hara; Lemon, Stephenie C.

    2016-01-01

    Context Built environment-focused interventions and policies are recommended as sustainable approaches for promoting physical activity. Physical activity has not traditionally been considered in land use and transportation decision making. Effective collaboration with non-public health partners requires knowledge of their perceived barriers to consideration of physical activity in decision making. Objective This study aimed to 1) identify barriers to the consideration of physical activity in community design and planning decisions among municipal decision makers and 2) explore differences in these barriers among a wide range of job functions and departments in a geographically diverse sample. Design A web-based survey was conducted among municipal officials in 94 cities and towns with populations of at least 50,000 residents in eight states. Participants 453 municipal officials from public health, planning, transportation/public works, community and economic development, parks and recreation, city management, and municipal legislatures responded to the survey. Main Outcome Measures Five barriers to consideration of physical activity in community design and layout were assessed. Results The most common barriers included lack of political will (23.5%), limited staff (20.4%) and lack of collaboration across municipal departments (16.2%). Fewer participants reported opposition from the business community or residents as barriers. Compared to other professionals, public health department personnel were more likely to report the barriers of limited staff and lack of collaboration across municipal departments. They were also more likely to report lack of political will compared to city managers or mayors and municipal legislators. Conclusions Barriers to increasing consideration of physical activity in decision making about community design and layout are encouragingly low. Implications for public health practice include the need to strategically increase political will

  9. Barriers to involvement in physical activities of persons with mental illness.

    Science.gov (United States)

    Shor, Ron; Shalev, Anat

    2016-03-01

    Participating in physical activities could be essential for reducing the multiple risk factors for health problems that persons with severe mental illness (SMI) may suffer. However, people with SMI are significantly less active than the general population. To develop knowledge about factors related to the perceived barriers hindering this population's participation in physical activities and the benefits this participation would have, a study was conducted in Israel with 86 people with mental illness living in community mental health facilities prior to their participation in a health promotion program. A mixed method was implemented and included: a scale designed to measure participants' perceptions of the barriers to and benefits of involvement in physical activities; instruments focusing on bio-psycho-social factors that may affect the level of barriers experienced; and personal interviews. The findings revealed high ranking for accessibility barriers hindering the participation in physical activities. Bio-psycho-social factors stemming from the participants' mental health, such as level of depression, were correlated with higher ranking of accessibility barriers. Bio-psycho-social factors reflecting positive mental health and health, such as positive appraisal of body weight, were correlated with lower ranking of accessibility barriers. Other barriers may include organizational and broader systemic barriers in the mental health facilities where the participants reside. These findings illuminate the need to consider the unique challenges that persons with mental illness may face in any attempt to advance their involvement in physical activity. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Low Li+ Insertion Barrier Carbon for High Energy Efficient Lithium-Ion Capacitor.

    Science.gov (United States)

    Lee, Wee Siang Vincent; Huang, Xiaolei; Tan, Teck Leong; Xue, Jun Min

    2018-01-17

    Lithium-ion capacitor (LIC) is an attractive energy-storage device (ESD) that promises high energy density at moderate power density. However, the key challenge in its design is the low energy efficient negative electrode, which barred the realization of such research system in fulfilling the current ESD technological inadequacy due to its poor overall energy efficiency. Large voltage hysteresis is the main issue behind high energy density alloying/conversion-type materials, which reduces the electrode energy efficiency. Insertion-type material though averted in most research due to the low capacity remains to be highly favorable in commercial application due to its lower voltage hysteresis. To further reduce voltage hysteresis and increase capacity, amorphous carbon with wider interlayer spacing has been demonstrated in the simulation result to significantly reduce Li + insertion barrier. Hence, by employing such amorphous carbon, together with disordered carbon positive electrode, a high energy efficient LIC with round-trip energy efficiency of 84.3% with a maximum energy density of 133 Wh kg -1 at low power density of 210 W kg -1 can be achieved.

  11. Energy barriers between metastable states in first-order quantum phase transitions

    Science.gov (United States)

    Wald, Sascha; Timpanaro, André M.; Cormick, Cecilia; Landi, Gabriel T.

    2018-02-01

    A system of neutral atoms trapped in an optical lattice and dispersively coupled to the field of an optical cavity can realize a variation of the Bose-Hubbard model with infinite-range interactions. This model exhibits a first-order quantum phase transition between a Mott insulator and a charge density wave, with spontaneous symmetry breaking between even and odd sites, as was recently observed experimentally [Landig et al., Nature (London) 532, 476 (2016), 10.1038/nature17409]. In the present paper, we approach the analysis of this transition using a variational model which allows us to establish the notion of an energy barrier separating the two phases. Using a discrete WKB method, we then show that the local tunneling of atoms between adjacent sites lowers this energy barrier and hence facilitates the transition. Within our simplified description, we are thus able to augment the phase diagram of the model with information concerning the height of the barrier separating the metastable minima from the global minimum in each phase, which is an essential aspect for the understanding of the reconfiguration dynamics induced by a quench across a quantum critical point.

  12. An Activity Theory Approach to Analyze Barriers to a Virtual Management Information Systems (MIS) Curriculum

    Science.gov (United States)

    Jaradat, Suhair; Qablan, Ahmad; Barham, Areej

    2011-01-01

    This paper explains how the activity theory is used as a framework to analyze the barriers to a virtual Management Information Stream (MIS) Curriculum in Jordanian schools, from both the sociocultural and pedagogical perspectives. Taking the activity system as a unit of analysis, this study documents the processes by which activities shape and are…

  13. Male Adolescents' Reasons for Participating in Physical Activity, Barriers to Participation, and Suggestions for Increasing Participation

    Science.gov (United States)

    Allison, Kenneth R.; Dwyer, John J. M.; Goldenberg, Ellie; Fein, Allan; Yoshida, Karen K.; Boutilier, Marie

    2005-01-01

    This study explored male adolescents' reasons for participating in moderate and vigorous physical activity, perceived barriers to moderate and vigorous physical activity, and suggestions as to what can be done to increase participation in physical activity. A total of 26 male 15- and 16-year-old adolescents participated in focus group sessions,…

  14. "What I Wish You Knew": Social Barriers toward Physical Activity in Youth with Congenital Heart Disease (CHD)

    Science.gov (United States)

    Moola, Fiona; Fusco, Caroline; Kirsh, Joel A.

    2011-01-01

    Despite the benefits of physical activity for youth with congenital heart disease (CHD), most patients are inactive. Although literature has addressed medical and psychological barriers to participation, little is known about the social barriers that youth encounter. This qualitative study explored sociocultural barriers to physical activity from…

  15. Reaction channels of 6,7Li+28Si at near-barrier energies

    International Nuclear Information System (INIS)

    Pakou, A; Rusek, K; Nicolis, N G; Alamanos, N; Doukelis, G; Gillibert, A; Kalyva, G; Kokkoris, M; Lagoyannis, A; Musumarra, A; Papachristodoulou, C; Perdikakis, G; Pierroutsakou, D; Pollacco, E C; Spyrou, A; Zarkadas, Ch

    2005-01-01

    The production of α-particles in the reactions 6,7 Li+ 28 Si was studied as a means to disentangle the various reaction channels at near-barrier energies. The competition between compound and direct reactions was determined by using the shape of angular distributions and statistical model calculations. DWBA calculations were also performed to probe the various direct channels. It was found that, approaching barrier, transfer channels are the most dominant for both reactions. For 7 Li+ 28 Si d-transfer is one of the contributing channels without excluding t-transfer, while for 6 Li+ 28 Si, n-transfer and p-transfer have substantial contribution but without excluding d-transfer

  16. 9Be+120Sn scattering at near-barrier energies within a four-body model

    Science.gov (United States)

    Arazi, A.; Casal, J.; Rodríguez-Gallardo, M.; Arias, J. M.; Lichtenthäler Filho, R.; Abriola, D.; Capurro, O. A.; Cardona, M. A.; Carnelli, P. F. F.; de Barbará, E.; Fernández Niello, J.; Figueira, J. M.; Fimiani, L.; Hojman, D.; Martí, G. V.; Martínez Heimman, D.; Pacheco, A. J.

    2018-04-01

    Cross sections for elastic and inelastic scattering of the weakly bound 9Be nucleus on a 120Sn target have been measured at seven bombarding energies around and above the Coulomb barrier. The elastic angular distributions are analyzed with a four-body continuum-discretized coupled-channels (CDCC) calculation, which considers 9Be as a three-body projectile (α +α +n ). An optical model analysis using the São Paulo potential is also shown for comparison. The CDCC analysis shows that the coupling to the continuum part of the spectrum is important for the agreement with experimental data even at energies around the Coulomb barrier, suggesting that breakup is an important process at low energies. At the highest incident energies, two inelastic peaks are observed at 1.19(5) and 2.41(5) MeV. Coupled-channels (CC) calculations using a rotational model confirm that the first inelastic peak corresponds to the excitation of the 21+ state in 120Sn, while the second one likely corresponds to the excitation of the 31- state.

  17. Municipal officials' perceived barriers to consideration of physical activity in community design decision making.

    Science.gov (United States)

    Goins, Karin Valentine; Schneider, Kristin L; Brownson, Ross; Carnoske, Cheryl; Evenson, Kelly R; Eyler, Amy; Heinrich, Katie; Litt, Jill; Lyn, Rodney; Maddock, Jay; Reed, Hannah; Tompkins, Nancy Oʼhara; Lemon, Stephenie C

    2013-01-01

    Built environment-focused interventions and policies are recommended as sustainable approaches for promoting physical activity. Physical activity has not traditionally been considered in land use and transportation decision making. Effective collaboration with non-public health partners requires knowledge of their perceived barriers to such consideration. This analysis sought to (a) establish prevalence estimates of selected barriers to the consideration of physical activity in community design and layout decisions and (b) describe how barrier reporting by public health officials differs from other municipal officials among a wide range of job functions and departments in a geographically diverse sample. A Web-based survey was conducted among municipal officials in 94 cities and towns with populations of at least 50 000 residents in 8 states. A total of 453 municipal officials from public health, planning, transportation/public works, community and economic development, parks and recreation, city management, and municipal legislatures in 83 cities and towns responded to the survey. Five barriers to consideration of physical activity in community design and layout were assessed. The most common barriers included lack of political will (23.5%), limited staff (20.4%), and lack of collaboration across municipal departments (16.2%). Fewer participants reported opposition from the business community or residents as barriers. Public health department personnel were more likely to report the barriers of limited staff and lack of collaboration across municipal departments than other professionals. They were also more likely to report lack of political will than city managers or mayors and municipal legislators. Barriers to increasing consideration of physical activity in decision making about community design and layout are encouragingly low. Implications for public health practice include the need to strategically increase political will despite public health staffing

  18. Barriers to Physical Activity Among African American Women: An Integrative Review of the Literature.

    Science.gov (United States)

    Joseph, Rodney P; Ainsworth, Barbara E; Keller, Colleen; Dodgson, Joan E

    2015-01-01

    A key aspect for researchers to consider when developing culturally appropriate physical activity (PA) interventions for African American (AA) women are the specific barriers AA women face that limit their participation in PA. Identification and critical examination of these barriers is the first step in developing comprehensive culturally relevant approaches to promote PA and help resolve PA-related health disparities in this underserved population. We conducted a systematic integrative literature review to identify barriers to PA among AA women. Five electronic databases were searched, and forty-two studies (twenty-seven qualitative, fourteen quantitative, one mixed method) published since 1990 (range 1998-2013) in English language journals met inclusion criteria for review. Barriers were classified as intrapersonal, interpersonal, or environment/community according to their respective level of influence within our social ecological framework. Intrapersonal barriers included lack of time, knowledge, and motivation; physical appearance concerns; health concerns; monetary cost of exercise facilities; and tiredness/fatigue. Interpersonal barriers included family/caregiving responsibilities; lack of social support; and lack of a PA partner. Environmental barriers included safety concerns; lack of facilities; weather concerns; lack of sidewalks; and lack of physically active AA role models. Results provide key leverage points for researchers to consider when developing culturally relevant PA interventions for AA women.

  19. Barriers to energy efficiency in small industry clusters: Multi-criteria-based prioritization using the analytic hierarchy process

    International Nuclear Information System (INIS)

    Nagesha, N.; Balachandra, P.

    2006-01-01

    The small scale industry (SSI) is an important component of Indian economy and a majority of SSI units tend to exist in geographical clusters. Energy efficiency is crucial for the survival and growth of energy intensive SSI clusters, not only to improve their competitiveness through cost reduction but also to minimize adverse environmental impacts. However, this is easier said than done due to the presence of a variety of barriers. The identification of relevant barriers and their appropriate prioritization in such clusters is a prerequisite to effectively tackle them. This paper identifies relevant barriers to energy efficiency and their dimensions in SSI clusters. Further, the barriers are prioritized based on the perceptions and experiences of entrepreneurs, the main stakeholders of SSIs, using the analytic hierarchy process (AHP). The field data from two energy intensive clusters of foundry and brick and tile in Karnataka (a state in India) reveal that the prioritization remained the same despite differences in the relative weights of barrier groups. The financial and economic barrier (FEB) and behavioural and personal barrier (BPB) have emerged as the top two impediments to energy efficiency improvements

  20. Future energy efficiency improvements within the US department of defense: Incentives and barriers

    International Nuclear Information System (INIS)

    Umstattd, Ryan J.

    2009-01-01

    The present work describes the military impact of improved efficiency and then highlights existing technological, political, and financial barriers for improving overall energy efficiency. As the largest user of energy within the US government, the Department of Defense (DOD) is rightly concerned that any disruption to the nation's energy supply may have an extremely adverse impact on its military capabilities. The total solution to providing energy security will be multi-faceted with progress required on many fronts. Increasing the use of renewable energy sources and improving energy storage capabilities are gradually creating a positive impact, but investing in improving the overall efficiency of the military effort provides both immediate and long-lasting payback. One might suppose that a decrease in the energy used by the DOD should lead to a decrease in military capability, but historical data proves otherwise. It is shown that the military has additional impetus, compared to civilian consumers, to pursue energy-efficiency improvements. Many tools are available to help the DOD along this path, yet there remain obstacles which must first be identified and analyzed as discussed herein.

  1. Barriers and opportunities for labels for highly energy-efficient houses

    International Nuclear Information System (INIS)

    Mlecnik, Erwin; Visscher, Henk; Van Hal, Anke

    2010-01-01

    Promoting energy efficiency in the building sector is essential if the agreements of the Kyoto Protocol are to be honoured. Different initiatives for energy labelling of highly energy-efficient residential buildings have emerged throughout Europe as an essential method to stimulate market demand, to control grants or to ensure the quality of demonstration projects with excellent energy performance. The paper identifies the barriers and opportunities for the further diffusion of labels for highly energy-efficient houses. A model based on the theory of the diffusion of innovation is developed to analyse perceived attributes of existing European labels. The paper investigates the innovation characteristics of existing labels in Europe, with a focus on advanced countries. The question of compatibility with the development of the European Energy Performance of Buildings Directive (EPBD) is examined in detail. We found that the diffusion of emerging and already existing voluntary European labels for highly energy-efficient houses is needed. Their complexity can be lowered and relative advantage, trialability, observability, and compatibility can be increased. EPBD calculation procedures should be able to receive highly energy-efficient houses. In the framework of the recast of the EPBD, official recognition of existing voluntary labels is recommended. (author)

  2. Children's active play: self-reported motivators, barriers and facilitators

    Directory of Open Access Journals (Sweden)

    Rowan Brockman

    2011-06-01

    Full Text Available Physical activity has important benefits for children's physical health and mental wellbeing, but many children do not meet recommended levels. Research suggests that active play has the potential to make a valuable contribution to children's overall physical activity, whilst providing additional cognitive, social and emotional benefits. However, relatively little is known about the determinants of UK children's active play. Understanding these factors provides the critical first step in developing interventions to increase children's active play, and therefore overall physical activity. Eleven focus groups were conducted with 77, 10-11 year old children from four primary schools in Bristol, UK. Focus groups examined: (i factors which motivate children to take part in active play; (ii factors which limit children's active play and (iii factors which facilitate children's active play. All focus groups were audio-taped and transcribed verbatim. Data were analysed using a thematic approach. Children were motivated to engage in active play because they perceived it to be enjoyable, to prevent boredom, to have physical and mental health benefits and to provide freedom from adult control, rules and structure. However, children's active play was constrained by a number of factors, including rainy weather and fear of groups of teenagers in their play spaces. Some features of the physical environment facilitated children's active play, including the presence of green spaces and cul-de-sacs in the neighbourhood. Additionally, children's use of mobile phones when playing away from home was reported to help to alleviate parents' safety fears, and therefore assist children's active play. Children express a range of motivational and environmental factors that constrain and facilitate their active play. Consideration of these factors should improve effectiveness of interventions designed to increase active play.

  3. Children's active play: self-reported motivators, barriers and facilitators.

    Science.gov (United States)

    Brockman, Rowan; Jago, Russell; Fox, Kenneth R

    2011-06-10

    Physical activity has important benefits for children's physical health and mental wellbeing, but many children do not meet recommended levels. Research suggests that active play has the potential to make a valuable contribution to children's overall physical activity, whilst providing additional cognitive, social and emotional benefits. However, relatively little is known about the determinants of UK children's active play. Understanding these factors provides the critical first step in developing interventions to increase children's active play, and therefore overall physical activity. Eleven focus groups were conducted with 77, 10-11 year old children from four primary schools in Bristol, UK. Focus groups examined: (i) factors which motivate children to take part in active play; (ii) factors which limit children's active play and (iii) factors which facilitate children's active play. All focus groups were audio-taped and transcribed verbatim. Data were analysed using a thematic approach. Children were motivated to engage in active play because they perceived it to be enjoyable, to prevent boredom, to have physical and mental health benefits and to provide freedom from adult control, rules and structure. However, children's active play was constrained by a number of factors, including rainy weather and fear of groups of teenagers in their play spaces. Some features of the physical environment facilitated children's active play, including the presence of green spaces and cul-de-sacs in the neighbourhood. Additionally, children's use of mobile phones when playing away from home was reported to help to alleviate parents' safety fears, and therefore assist children's active play. Children express a range of motivational and environmental factors that constrain and facilitate their active play. Consideration of these factors should improve effectiveness of interventions designed to increase active play.

  4. Music therapists' research activity and utilization barriers: a survey of the membership.

    Science.gov (United States)

    Waldon, Eric G

    2015-01-01

    Music therapists have access to a rapidly expanding body of research supporting the use of music-based interventions. What is not known is the extent to which music therapists access these resources and what factors may prevent them from incorporating research findings into clinical work. After constructing the Music Therapists' Research Activity and Utilization Barrier (MTRAUB) database, the purposes of this study involved: assessing the extent to which American Music Therapy Association (AMTA) members engage in certain research-related activities; and identifying respondents' perceived barriers to integrating research into clinical practice. This study employed a quantitative, non-experimental approach using an online survey. Respondents included professional, associate, student/graduate student, retired, inactive, and honorary life members of AMTA. Instrumentation involved a researcher-designed Background Questionnaire as well as the Barriers to Research Utilization Scale (BARRIERS; Funk, Champagne, Wiese, & Tornquist, 1991), a tool designed to assess perceived barriers to incorporating research into practice. Of the 3,194 survey invitations distributed, 974 AMTA members replied (a response rate of 30%). Regarding research-related activities, descriptive findings indicate that journal reading is the most frequently reported research-related activity while conducting research is the least frequently reported activity. Results from the BARRIERS Scale indicated that Organizational and Communication factors are perceived as interfering most prominently with the ability to utilize research in clinical practice. Findings suggest that research-related activity and perceived barriers vary as a function of educational attainment, work setting, and occupational role. The author discusses these differential findings in detail, suggests supportive mechanisms to encourage increased research activity and utilization, and offers recommendations for further analysis of the

  5. The future of transportation in sustainable energy systems: Opportunities and barriers in a clean energy transition

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo; Bačeković, Ivan; Pedersen, Allan Schrøder

    2017-01-01

    Energy demand of a transport sector has constantly been increasing in the recent years, consuming one third of the total final energy demand in the European Union (EU) over the last decade. A transition of this sector towards sustainable one is facing many challenges in terms of suitable technolo...

  6. Barriers to Physical Activity Among African American Women: An Integrative Review of the Literature

    OpenAIRE

    Joseph, Rodney P.; Ainsworth, Barbara E.; Keller, Colleen; Dodgson, Joan E

    2015-01-01

    A key aspect for researchers to consider when developing culturally appropriate physical activity (PA) interventions for African American (AA) women are the specific barriers AA women face that limit their participation in PA. Identification and critical examination of these barriers is the first step in developing comprehensive culturally relevant approaches to promote PA and help resolve PA-related health disparities in this underserved population. We conducted a systemati...

  7. Perceived barriers and enablers of physical activity in postpartum women: a qualitative approach

    OpenAIRE

    Saligheh, Maryam; McNamara, Beverley; Rooney, Rosanna

    2016-01-01

    Background Postpartum women?s recovery from birth can be assisted through increased physical activity (PA). However, women face substantial barriers to participating in exercise and require support to enable them to benefit from increased PA. Methods This study sought to explore women?s beliefs about and experiences of PA and exercise during the 6?weeks to 12?months postpartum period. A cohort of 14 postpartum women from a survey study of the barriers and enablers to exercise participation ag...

  8. Modeling and Characteristic Analysis of Wireless Ultrasonic Vibration Energy Transmission Channels through Planar and Curved Metal Barriers

    Directory of Open Access Journals (Sweden)

    DingXin Yang

    2018-01-01

    Full Text Available Wireless ultrasonic vibration energy transmission systems through metal barriers based on piezoelectric transducers have drawn a lot of focus due to the advantage of nonpenetration of the barriers, thus maintaining the integrity of sealed structures. It is meaningful to investigate appropriate modeling methods and to characterize such wireless ultrasonic energy transmission channels with different geometric shapes. In this paper, equivalent circuit modeling and finite element modeling methods are applied to the planar metal barrier channel, and a 3-dimensional finite element modeling method is applied to the cylindrical metallic barrier channel. Meanwhile, the experimental setup is established and measurements are carried out to validate the effectiveness of the corresponding modeling methods. The results show that Leach’s equivalent circuit modeling method and finite element modeling method are nearly similarly effective in characterizing the planar metal barrier channel. But for a cylindrical metal barrier, only the three-dimensional finite element modeling method is effective. Furthermore, we found that, for the planar barrier, the effect of standing waves on the efficiency of wireless energy transmission is dominated. But for the curved barrier, only the resonant phenomenon of the piezoelectric transducer exists.

  9. Potential and barrier study. Passive house and near-zero energy buildings; Potensial- og barrierestudie. Passivhus og naer nullenergibygninger

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    The main conclusion from the analysis is that the barriers to realize both passive and near zero-energy buildings are significant. In addition to being a mere economic assessment indicates that 30-70% of the technical potential is not profitable depending on energy price levels, the barriers is reducing the economic potential with approximately another half as a realistic market potential.(eb)

  10. Perceived barriers and facilitators to physical activity for children with disability: a systematic review.

    Science.gov (United States)

    Shields, Nora; Synnot, Anneliese Jane; Barr, Megan

    2012-11-01

    The aim of this systematic review was to investigate the perceived barriers and facilitators to physical activity among children with disability. 10 electronic databases were searched from the earliest time available to September 2010 to identify relevant articles. Articles were included if they examined the barriers or facilitators to physical activity for children with disability and were written in English. Articles were excluded if they included children with an acute, transient or chronic medical condition, examined sedentary leisure activities, or societal participation in general. Two reviewers independently assessed the search yields, extracted the data and assessed trial quality. Data were analysed descriptively. 14 articles met the inclusion criteria. Barriers included lack of knowledge and skills, the child's preferences, fear, parental behaviour, negative attitudes to disability, inadequate facilities, lack of transport, programmes and staff capacity, and cost. Facilitators included the child's desire to be active, practising skills, involvement of peers, family support, accessible facilities, proximity of location, better opportunities, skilled staff and information. Personal, social, environmental, and policy and programme-related barriers and facilitators influence the amount of activity children with disability undertake. The barriers to physical activity have been studied more comprehensively than the facilitators.

  11. Silicon surface barrier detector and study of energy spectrum of alpha particles from radioactive source

    International Nuclear Information System (INIS)

    Verma, S.D.; Sinha, Vijaya

    1986-01-01

    The principles of working of three commonly used radiation detectors, namely ionization chambers, scintillation counters with photomultiplier tube (PMT) systems and semiconductor detectors are briefly discussed. Out of the semiconductor detectors, the silicon surface barrier (SSB) detector has distinct advantages for detection of radiations, alpha particles in particular. The experimental setup to obtain the energy spectrum of alpha particles from 241 Am source using SSB fabricated in the Physics Department of Gujarat University, Ahmedabad is described. Its performance is compared with scintillation counter using PMT. SSB detector shows a sharp peak of #approx # 3 per cent energy resolution. The factors affecting the peak, namely, electronic noise, source dependent factors and detector-dependent factors are discussed. A method of calibrating SSB detectors based on energy loss mechanism of alpha particles in thin absorbers is described. Applications of such detectors are indicated. (M.G.B.)

  12. Gender Differences in Barriers to Physical Activity among College Students Reporting Varying Levels of Regular Physical Activity

    Science.gov (United States)

    Munford, Shawn N.

    2011-01-01

    Researchers have studied the primary determinants of physical activity in an effort to enhance health promotion initiatives nationwide. These physical activity determinants have been observed to differ among various segments of the population, suggesting a further examination of physical activity barriers among differing populations. Little…

  13. Thermal activation of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height

    International Nuclear Information System (INIS)

    Guo-Ping, Ru; Rong, Yu; Yu-Long, Jiang; Gang, Ruan

    2010-01-01

    This paper investigates the thermal activation behaviour of current in an inhomogeneous Schottky diode with a Gaussian distribution of barrier height by numerical simulation. The analytical Gaussian distribution model predicted that the I-V-T curves may intersect with the possibility of the negative thermal activation of current, but may be contradictory to the thermionic emission mechanism in a Schottky diode. It shows that the cause of the unphysical phenomenon is related to the incorrect calculation of current across very low barriers. It proposes that junction voltage V j , excluding the voltage drop across series resistance from the external bias, is a crucial parameter for correct calculation of the current across very low barriers. For correctly employing the thermionic emission model, V j needs to be smaller than the barrier height ø. With proper scheme of series resistance connection where the condition of V j > ø is guaranteed, I-V-T curves of an inhomogeneous Schottky diode with a Gaussian distribution of barrier height have been simulated, which demonstrate normal thermal activation. Although the calculated results exclude the intersecting possibility of I-V-T curves with an assumption of temperature-independent series resistance, it shows that the intersecting is possible when the series resistance has a positive temperature coefficient. Finally, the comparison of our numerical and analytical results indicates that the analytical Gaussian distribution model is valid and accurate in analysing I-V-T curves only for small barrier height inhomogeneity. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  14. Identifying Barriers and Pathways to Success for Renewable Energy Development on American Indian Lands

    Energy Technology Data Exchange (ETDEWEB)

    Necefer, Len Edward [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Univ. of Arizona, Tucson, AZ (United States); Jones, Thomas Elisha [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2016-11-01

    American Indian tribes possess lands rich with renewable energy (RE) resources. Tribes have great potential and need to develop these resources, yet face a host of barriers that continue to impede development. Understanding these challenges as well as the pathways that can be taken to overcome them may facilitate more economic development to meet community needs and better position tribes to play a role in securing a low-carbon energy future for the United States. This paper presents the results of an expert elicitation of 24 tribal energy experts from federal, tribal, academic, and private industry backgrounds to identify barriers and opportunities for federally recognized tribes in the lower 48 states. Experts identified a number of unique challenges facing tribes including financing and funding, infrastructure, tribal leadership and staff, state-level influence, and partnerships. Cultural factors were seen only to be of concern with large-scale development. Tribal sovereignty is a significant motivation for RE development and has yet to be fully realized. Cultural considerations are critical to the success of future projects; smaller residential and community-scale projects may be a better fit. Improving partnerships between tribes and the private sector can increase RE deployment and overcome historical distrust. States can have a double-ended influence on projects within tribal lands through taxation.

  15. How does incomplete fusion show up at slightly above barrier energies?

    Directory of Open Access Journals (Sweden)

    Prasad R.

    2012-02-01

    Full Text Available Experimental results on the onset of incomplete fusion at slightly above barrier energies are discussed in this paper. Spin-distributions of evaporation residues populated via complete and/or incomplete fusion of 12C,16O (Elab ≈ 4–7 MeV with 169Tm have been measured to probe associated ℓ–values. Particle (Z=1,2 – γ – coincidence technique has been used for channel selection. Entirely different entry state spin populations have been observed during the de-excitation of complete and incomplete composites. The complete fusion residues are found to be strongly fed over a broad spin range. While, a narrow range feeding for only high spin states has been observed in case of incomplete fusion residues. In the present work, incomplete fusion is shown to be a promising tool to populate high spin states in final reaction products. For better insight into the onset and strength of incomplete fusion, the relative contributions of complete and incomplete fusion have been deduced from the analysis of excitation functions and forward recoil ranges. A significant fraction of ICF has been observed even at energy as low as ≈ 7% above the barrier. The relative strengths of complete and incomplete fusion deduced from the analysis of forward-recoil-ranges and excitation functions complement each other. All the available results are discussed in light of the Morgenstern’s mass-asymmetry systematics. Incomplete fusion fraction is found to be large for more mass-asymmetric systems for individual projectiles, which points towards the projectile structure effect on incomplete fusion fraction. Experimentally measured forward ranges of recoils complement the existence of incomplete fusion at slightly above barrier energies, where more than one linear-momentum-transfer components associated with full- and/or partial-fusion of projectile(s have been observed. Present results conclusively demonstrate the possibility to selectively populate high spin states

  16. Motives for and barriers to physical activity in twin pairs discordant for leisure time physical activity for 30 years.

    Science.gov (United States)

    Aaltonen, S; Leskinen, T; Morris, T; Alen, M; Kaprio, J; Liukkonen, J; Kujala, U

    2012-02-01

    Long-term persistent physical activity is important in the prevention of chronic diseases, but a large number of people do not participate in physical activity to obtain health benefits. The purpose of this study was to examine the motives and perceived barriers to long-term engagement in leisure time physical activity. Same-sex twin pairs (N=16, mean age 60) discordant for physical activity over 30 years were identified from the Finnish Twin Cohort. We evaluated participants' physical activity motivation with the 73-item Recreational Exercise Motivation Measure and assessed barriers to physical activity with a 25-item questionnaire. The characteristics of physical activity motivation and perceived barriers between the active and inactive co-twins were analysed using paired tests. Motives related to the sub-dimensions of enjoyment and physical fitness and psychological state were the most important reasons for participation in physical activity among all the twin individuals analysed. The sub-dimensions mastery (p=0.018, Cohen's d=0.76), physical fitness (p=0.029, Cohen's d=0.69), and psychological state (p=0.039, Cohen's d=0.65) differed significantly between active and inactive co-twins. More than half of the participants reported no reasons for not being physically active. If reasons existed, participation in physical activity was deterred mostly by pain and various health problems. This study found no differences in perceived barriers between active and inactive co-twins. We conclude from our results that the main factors promoting persistent leisure time physical activity were participants' wish to improve or maintain their physical skills or techniques, a feeling that exercise would improve their mental and physical health and that they found the activity enjoyable. This study helps us understand the importance of the role of motives and the minor role of perceived barriers for engagement in persistent physical activity. © Georg Thieme Verlag KG Stuttgart

  17. Exploring physical activity engagement and barriers for asylum seekers in Australia coping with prolonged uncertainty and no right to work.

    Science.gov (United States)

    Hartley, Lisa; Fleay, Caroline; Tye, Marian E

    2017-05-01

    This paper explores the engagement in physical activity as a potential coping strategy for asylum seekers living in the Australian community without the right to work and with prolonged uncertainty, and benefits or barriers to undertaking such activity. Semi-structured in-depth interviews were held with 29 asylum seekers who had arrived to Australia by boat and were living in the community in the cities of Perth, Sydney or Melbourne in July-October 2013 after their release from immigration detention. The ratio of the numbers of men and women interviewed (23 men and 6 women) was comparable to the ratio of men and women who came by boat to Australia seeking asylum in 2012-2013. Nine participants reported that they participated in physical activity as a coping strategy. Seven other participants were so worried about their future and their families that they did not have the mental or physical energy to engage in physical activity. A further six wanted to participate in physical activity but faced a number of barriers to doing so. The seven remaining participants were either not asked about their physical activity engagement because they focused their discussion on other challenges or did not elaborate on why they were not engaging in physical activity. The findings suggest that physical activity, coupled with other coping strategies, are important for some asylum seekers in trying to manage the distress of being denied the right to work and living with prolonged uncertainty. In addition, these findings highlight the critical barrier that government policy plays in disabling engagement in physical activity, which further compounds social exclusion. This includes the lack of welfare support provided, which hinders people's financial ability to access activities and support in the community. © 2017 John Wiley & Sons Ltd.

  18. The role of perceived barriers and objectively measured physical activity in adults aged 65-100.

    Science.gov (United States)

    Gellert, Paul; Witham, Miles D; Crombie, Iain K; Donnan, Peter T; McMurdo, Marion E T; Sniehotta, Falko F

    2015-05-01

    to test the predictive utility of perceived barriers to objectively measured physical activity levels in a stratified sample of older adults when accounting for social-cognitive determinants proposed by the Theory of Planned Behaviour (TPB), and economic and demographic factors. data were analysed from the Physical Activity Cohort Scotland survey, a representative and stratified (65-80 and 80+ years; deprived and affluent) sample of 584 community-dwelling older people, resident in Tayside, Scotland. Physical activity was measured objectively by accelerometry. perceived barriers clustered around the areas of poor health, lack of interest, lack of safety and lack of access. Perceived poor health and lack of interest, but not lack of access or concerns about personal safety, predicted physical activity after controlling for demographic, economic and TPB variables. perceived person-related barriers (poor health and lack of interest) seem to be more strongly associated with physical activity levels than perceived environmental barriers (safety and access) in a large sample of older adults. Perceived barriers are modifiable and may be a target for future interventions. © The Author 2015. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Barriers to Physical Activity in a Mass Transit Population: A Qualitative Study.

    Science.gov (United States)

    Das, Bhibha M; Petruzzello, Steven J

    2016-01-01

    The physical inactivity epidemic continues be one of the greatest public health challenges in contemporary society in the United States. The transportation industry is at greater risk of physical inactivity, compared with individuals in other sectors of the workforce. The aim of this study was to use the Nominal Group Technique, a focus group technique, to examine mass transit employees' perceptions of the barriers to physical activity at their worksite. Three focus groups (n = 31) were conducted to examine mass transit employees' perceptions of barriers to physical activity at the worksite. Salient barriers included (1) changing work schedules, (2) poor weather conditions, and (3) lack of scheduled and timely breaks. Findings were consistent with previous research demonstrating shift work, poor weather, and lack of breaks can negatively impact mass transit employees' ability to be physically active. Although physical activity barriers for this population have been consistent for the last 20 years, public health practice and policy have not changed to address these barriers. Future studies should include conducing focus groups stratified by job classification (eg, operators, maintenance, and clerical) along with implementing and evaluating worksite-based physical activity interventions and policy changes.

  20. A cluster expansion model for predicting activation barrier of atomic processes

    International Nuclear Information System (INIS)

    Rehman, Tafizur; Jaipal, M.; Chatterjee, Abhijit

    2013-01-01

    We introduce a procedure based on cluster expansion models for predicting the activation barrier of atomic processes encountered while studying the dynamics of a material system using the kinetic Monte Carlo (KMC) method. Starting with an interatomic potential description, a mathematical derivation is presented to show that the local environment dependence of the activation barrier can be captured using cluster interaction models. Next, we develop a systematic procedure for training the cluster interaction model on-the-fly, which involves: (i) obtaining activation barriers for handful local environments using nudged elastic band (NEB) calculations, (ii) identifying the local environment by analyzing the NEB results, and (iii) estimating the cluster interaction model parameters from the activation barrier data. Once a cluster expansion model has been trained, it is used to predict activation barriers without requiring any additional NEB calculations. Numerical studies are performed to validate the cluster expansion model by studying hop processes in Ag/Ag(100). We show that the use of cluster expansion model with KMC enables efficient generation of an accurate process rate catalog

  1. Elastic Scattering Of 6,7Li+80Se At Near And Above Barrier Energies

    International Nuclear Information System (INIS)

    Fimiani, L.; Marti, G. V.; Capurro, O. A.; Barbara, E. de; Testoni, J. E.; Zalazar, L.; Arazi, A.; Cardona, M. A.; Carnelli, P.; Figueira, J. M.; Hojman, D.; Martinez Heimann, D.; Negri, A. E.; Pacheco, A. J.; Fernandez Niello, J. O.

    2010-01-01

    In this work we propose to study the elastic scattering of the weakly bound projectiles 6,7 Li on an intermediate mass target 80 Se. From the experimental results presented here, precise angular distributions at energies below, around and above the nominal Coulomb barriers of the systems were obtained. The final goal of our work is to determine the characteristic parameters of the optical potential and use them to address the question of whether the usual threshold anomaly or the breakup threshold anomaly are present or not in these systems.

  2. Renewable energy clusters recurring barriers to cluster development in eleven countries

    CERN Document Server

    Jaegersberg, Gudrun

    2017-01-01

    Taking eleven countries in Europe, Canada, South Africa, America, Latin America and Australia, this book discusses recurring barriers to cluster development in the renewable energy sector. The authors look at the real-world dynamics and tensions between stakeholders on the ground, with a particular focus on the relationships between SMEs and other actors. This trans-regional study is unique in its scale and scope, drawing on a decade of field research to show how by learning from the successes and failures of other clusters, costs and risk can be reduced. The book fills a significant gap in the literature for policymakers, managers and economic developers in a key market.

  3. Probing the energy barriers and magnetization reversal processes of nanoperforated membrane based percolated media

    International Nuclear Information System (INIS)

    Neu, V; Schultz, L; Schulze, C; Makarov, D; Albrecht, M; Faustini, M; Grosso, D; Lee, J; Kim, S-K; Suess, D

    2013-01-01

    Magnetization reversal processes in Co/Pt multilayers prepared on nanoperforated templates are probed by magnetization relaxation measurements. The signature of pinning controlled domain wall movement as expected for percolated media is identified. This contrasts with the nucleation-type reversal mechanism of a Co/Pt reference film prepared on a smooth substrate. A zero field energy barrier of 93k B T is determined by fluctuation field measurements and is elucidated by micromagnetic calculations using the nudged elastic band method. This value is sufficiently large to qualify the material as a promising percolated medium. (paper)

  4. Driven diffusion against electrostatic or effective energy barrier across α-hemolysin

    Energy Technology Data Exchange (ETDEWEB)

    Ansalone, Patrizio [Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, Torino, IT-10135 (Italy); Chinappi, Mauro [Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Via Regina Elena 291, 00161 Roma (Italy); Rondoni, Lamberto [Scienze Matematiche, Politecnico di Torino Corso Duca degli Abruzzi 24, Torino, IT-10129, Italy and INFN, Sez. di Torino, Via P. Giuria 1, Torino IT-10125 (Italy); Cecconi, Fabio, E-mail: fabio.cecconi@roma1.infn.it [CNR-Istituto dei Sistemi Complessi UoS “Sapienza,” Via dei Taurini 19, 00185 Roma (Italy)

    2015-10-21

    We analyze the translocation of a charged particle across an α-Hemolysin (αHL) pore in the framework of a driven diffusion over an extended energy barrier generated by the electrical charges of the αHL. A one-dimensional electrostatic potential is extracted from the full 3D solution of the Poisson’s equation. We characterize the particle transport under the action of a constant forcing by studying the statistics of the translocation time. We derive an analytical expression of translocation time average that compares well with the results from Brownian dynamic simulations of driven particles over the electrostatic potential. Moreover, we show that the translocation time distributions can be perfectly described by a simple theory which replaces the true barrier by an equivalent structureless square barrier. Remarkably, our approach maintains its accuracy also for low-applied voltage regimes where the usual inverse-Gaussian approximation fails. Finally, we discuss how the comparison between the simulated time distributions and their theoretical prediction results to be greatly simplified when using the notion of the empirical Laplace transform technique.

  5. Perceptions of barriers and facilitators in physical activity participation among women in Thiruvananthapuram City, India.

    Science.gov (United States)

    Mathews, Elezebeth; Lakshmi, J K; Ravindran, T K Sundari; Pratt, Michael; Thankappan, K R

    2016-12-01

    Despite the known benefits of physical activity, very few people, especially women, are found to engage in regular physical activity. This study explored the perceptions, barriers and facilitators related to physical activity among women in Thiruvananthapuram City, India. Four focus group discussions were conducted among individuals between 25 and 60 years of age, in a few areas of Thiruvananthapuram City Corporation limits in Kerala, preparatory to the design of a physical activity intervention trial. An open-ended approach was used and emergent findings were analyzed and interpreted. Women associated physical activity mostly with household activities. The majority of the women considered their activity level adequate, although they engaged in what the researchers concluded were quite low levels of activity. Commonly reported barriers were lack of time, motivation, and interest; stray dogs; narrow roads; and not being used to the culture of walking. Facilitators of activity were seeing others walking, walking in pairs, and pleasant walking routes. Walking was reported as the most feasible physical activity by women. Physical activity promotion strategies among women should address the prevailing cultural norms in the community, and involve social norming and overcoming cultural barriers. They should also target the modifiable determinants of physical activity, such as improving self-efficacy, improving knowledge on the adequacy of physical activity and its recommendations, facilitating goal-setting, and enhancing social support through peer support and group-based activities. © The Author(s) 2015.

  6. Development of the Barriers to Physical Activity Questionnaire for People with Mobility Impairments.

    Science.gov (United States)

    Vasudevan, Vijay; Rimmer, James H; Kviz, Frederick

    2015-10-01

    Despite the widely known benefits of physical activity, people with disabilities are more likely to be inactive when compared to people without disabilities. Previous questionnaires that measure barriers physical activity for people with disabilities do not measure barriers from an ecological perspective. The purpose of this study was to develop the Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) that measures barriers using an ecological framework. This study consisted of two phases. In Phase one, developed the content validity by (a) developing an item bank, (b) identifying missing items and combining items using a Delphi panel, and (c) refine item wording via cognitive interviews. In Phase two, people with mobility impairments took part in in-person interviews to establish test-retest reliability, internal consistency, and construct validity of the BPAQ-MI. Exploratory factor analysis revealed the BPAQ-MI was comprised of eight subscales or factors: health; beliefs and attitudes; family; friends; fitness center built environment; staff and policy; community built environment; and safety. The BPAQ-MI demonstrated very good test-retest reliability. Cronbach's alpha ranged from 0.792 to 0.935. The BPAQ-MI showed significant negative correlations with exercise (minutes/week) and significant positive correlations between BPAQ-MI subscales and inactivity (hours/day). The BPAQ-MI is the first questionnaire that places greater equity at measuring barriers to physical activity across the intrapersonal, interpersonal, organizational, and community domains. The BPAQ-MI has the potential to assist researchers in understanding the complex relationship between barriers and ultimately develop physical activity interventions that address these barriers. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Barriers to Physical Activity for People with Long-Term Neurological Conditions: A Review Study

    Science.gov (United States)

    Mulligan, Hilda F.; Hale, Leigh A.; Whitehead, Lisa; Baxter, G. David

    2012-01-01

    People with disability are insufficiently physically active for health. This study identified the volume, quality, and findings of research that exposes environmental and personal barriers of physical activity participation for people with neurological conditions. CINAHL, Sport Discus, EMBASE, Medline, and AMED were systematically searched between…

  8. Levels of Engagement and Barriers to Physical Activity in a Population of Adults with Learning Disabilities

    Science.gov (United States)

    Hawkins, Andrew; Look, Roger

    2006-01-01

    This study examined levels of, and barriers to, physical activity in a population of 19 adults with learning disabilities living in community supported accommodation, using diary records and semi-structured interviews with staff. The levels of physical activity were higher in the sample population than previous figures for adults with learning…

  9. Identifying the Barriers and Facilitators to Participation in Physical Activity for Children with Down Syndrome

    Science.gov (United States)

    Barr, M.; Shields, N.

    2011-01-01

    Background: Many children with Down syndrome do not undertake the recommended amount of daily physical activity. The aim of this study was to explore the barriers and facilitators to physical activity for this group. Methods: Eighteen in-depth interviews were conducted with 20 parents (16 mothers, 4 fathers) of children with Down syndrome aged…

  10. Identifying Facilitators and Barriers to Physical Activity for Adults with Down Syndrome

    Science.gov (United States)

    Mahy, J.; Shields, N.; Taylor, N. F.; Dodd, K. J.

    2010-01-01

    Background: Adults with Down syndrome are typically sedentary, and many do not participate in the recommended levels of physical activity per week. The aim of this study was to identify the facilitators and barriers to physical activity for this group. Method: Semi-structured interviews were conducted to elicit the views of adults with Down…

  11. Barriers to Building Energy Efficiency (BEE) promotion: A transaction costs perspective

    Science.gov (United States)

    Qian Kun, Queena

    Worldwide, buildings account for a surprisingly high 40% of global energy consumption, and the resulting carbon footprint significantly exceeds that of all forms of transportation combined. Large and attractive opportunities exist to reduce buildings' energy use at lower costs and higher returns than in other sectors. This thesis analyzes the concerns of the market stakeholders, mainly real estate developers and end-users, in terms of transaction costs as they make decisions about investing in Building Energy Efficiency (BEE). It provides a detailed analysis of the current situation and future prospects for BEE adoption by the market's stakeholders. It delineates the market and lays out the economic and institutional barriers to the large-scale deployment of energy-efficient building techniques. The aim of this research is to investigate the barriers raised by transaction costs that hinder market stakeholders from investing in BEES. It explains interactions among stakeholders in general and in the specific case of Hong Kong as they consider transaction costs. It focuses on the influence of transaction costs on the decision-making of the stakeholders during the entire process of real estate development. The objectives are: 1) To establish an analytical framework for understanding the barriers to BEE investment with consideration of transaction costs; 2) To build a theoretical game model of decision making among the BEE market stakeholders; 3) To study the empirical data from questionnaire surveys of building designers and from focused interviews with real estate developers in Hong Kong; 4) To triangulate the study's empirical findings with those of the theoretical model and analytical framework. The study shows that a coherent institutional framework needs to be established to ensure that the design and implementation of BEE policies acknowledge the concerns of market stakeholders by taking transaction costs into consideration. Regulatory and incentive options

  12. Motivators and barriers for physical activity in older adults with osteoporosis.

    Science.gov (United States)

    Baert, Veerle; Gorus, Ellen; Mets, Tony; Bautmans, Ivan

    2015-01-01

    Although physical activity (PA) is an important tool to counter osteoporosis, too few older patients with osteoporosis (OPWO) engage in PA. Little is known about specific motivators for and barriers to PA in OPWO, hindering the development of targeted PA promotion campaigns for these persons. Therefore, the main objective of this study was to identify motivators for and barriers to PA specifically in OPWO. This qualitative study identified specific motivators for and barriers to PA in OPWO through 2 different methods: focus groups with professionals and in-depth interviews with OPWO. The OPWO tended to give a broad interpretation of what they considered as PA (practicing sports, physical work, and performing household activities), whereas the professionals seemed to mainly focus on (therapeutic) exercise as PA. Fifteen different motivators and 18 barriers have been identified. Among others, health improvement, social contact, habit, feeling good, and receiving medical advice from a medical doctor were motivators. Pain, fear of falling, bad weather, lack of interest, and caring for an ill partner were barriers to PA. For some older respondents, osteoporosis acted as a trigger for PA, and for others it was a barrier. This study emphasizes the importance for health care professionals to give personalized PA advice regarding the nature and frequency of PA that is safe and beneficial for osteoporosis. It stands to reason that the information about PA needs to be clear and consistent. Furthermore, it is quintessential to mention that it can take some time to adapt to physical exercise and to experience the beneficial effects, because pain sensations during the first PA sessions can be perceived as barriers to OPWO. Misconceptions or barriers to PA should be countered by assessing motivators for and barriers to PA by the health care professional together with the older client so that barriers can be eliminated and motivators can be strengthened. Physical activity

  13. Perceived barriers to physical activity in older and younger veterans with serious mental illness.

    Science.gov (United States)

    Muralidharan, Anjana; Klingaman, Elizabeth A; Molinari, Victor; Goldberg, Richard W

    2018-03-01

    Individuals with serious mental illness endorse many more medical and psychosocial barriers to physical activity (PA) than the general population. However, it is unknown if older adults with serious mental illness are at greater risk of experiencing barriers to PA than their younger counterparts. The present study utilized a national VA dataset to compare veterans with serious mental illness ages 55 and older (n = 9,044) to veterans with serious mental illness ages 54 and younger (n = 8,782) on their responses to a questionnaire assessment of barriers to PA. Older veterans were more likely to endorse arthritis and cardiopulmonary disease, and less likely to endorse work schedule, as barriers to PA. Interventions designed to increase PA for young/middle-aged adults with serious mental illness may be broadly useful for older adults with serious mental illness, with some modification to address specific health concerns. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  14. Non-Critical-Care Nurses' Perceptions of Facilitators and Barriers to Rapid Response Team Activation.

    Science.gov (United States)

    Jenkins, Sheryl Henry; Astroth, Kim Schafer; Woith, Wendy Mann

    2015-01-01

    Rapid response teams can save lives but are only effective when activated. We surveyed 50 nurses for their perceptions of facilitators and barriers to activation. Findings showed that participants need more education on their role and when to activate the rapid response team. Nurses who comprise the team need help building their communication skills. We recommend nursing professional development specialists increase the frequency of offerings and expand the focus on roles, activation criteria, and communication skills.

  15. Study on characteristics of high frequency dielectric barrier discharge for the removal of organic pollutant adsorbed on activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Qu, G.Z.; Li, G.F. [Dalian Univ. of Technology, Dalian (China). Inst. of Electrostatics and Special Power; Li, J.; Lu, N.; Wu, Y.; Li, D. [Dalian Univ. of Technology, Dalian (China). Inst. of Electrostatics and Special Power; Key Lab of Industrial Ecology and Environmental Engineering, Ministry of Education, Dalian (China)

    2010-07-01

    Advanced oxidation technologies such as photocatalysis, electrochemical degradation, Fenton oxidation, hydrogen peroxide oxidation, and plasma oxidation are increasingly being used to degrade refractory biodegradable organic contaminants. The plasma oxidation method has the advantage of direct in situ production of multiple types of high-reactive chemical species, including molecules and radicals that facilitate the degradation reaction. In addition, plasma oxidation does not produce any secondary pollution. Compared to other plasma technologies, the dielectric barrier discharge (DBD) plasma has been considered as a promising technology for removing toxic compounds because of its stability and its treatability property of biologically recalcitrant compounds in wastewater. However, the energy efficiency of DBD requires improvement for economic reasons. This paper reported on an experimental study that investigated the electrical characteristics of a parallel plate DBD reactor using a high frequency power supply for the removal of pentachlorophenol (PCP) adsorbed on activated carbon (AC). This study examined the effects of AC with different mass on discharge characteristics and compared the voltage and current waveforms, and discharge images of DBD reactors with different dielectric configurations. When the DBD reactor filled with AC, the applied voltage of discharge decreased regardless of the DBD reactor configuration in terms of having a single barrier or two barriers. The discharge characteristics had no significant change with AC mass increasing. The discharge images and current waveforms showed that DBD reactor configuration consisting of two dielectrics is more homogeneous and stable than the one consisting of a single dielectric. Under the same electric field condition, the degradation efficiency of PCP in two barriers reactor is higher than that in single barrier reactor. It was concluded that the findings from this study may be instrumental in treating

  16. Barriers in the implementation of a physical activity intervention in primary care settings: lessons learned.

    Science.gov (United States)

    Josyula, Lakshmi K; Lyle, Roseann M

    2013-01-01

    Barriers encountered in implementing a physical activity intervention in primary health care settings, and ways to address them, are described in this paper. A randomized comparison trial was designed to examine the impact of health care providers' written prescriptions for physical activity, with or without additional physical activity resources, to adult, nonpregnant patients on preventive care or chronic disease monitoring visits. Following abysmal recruitment outcomes, the research protocol was altered to make it more appealing to all the participants, i.e., health care providers, office personnel, and patients. Various barriers--financial, motivational, and executive--to the implementation of health promotion interventions in primary health care settings were experienced and identified. These barriers have been classified by the different participants in the research process, viz., healthcare providers, administrative personnel, researchers, and patients. Some of the barriers identified were lack of time and reimbursement for health promotion activities, and inadequate practice capacity, for health care providers; increased time and labor demands for administrative personnel; constrained access to participants, and limited funding, for researchers; and superseding commitments, and inaccurate comprehension of the research protocol, for patients. Solutions suggested to overcome these barriers include financial support, e.g., funding for researchers, remuneration for health care organization personnel, reimbursement for providers, payment for participants, and free or subsidized postage, and use of health facilities; motivational strategies such as inspirational leadership, and contests within health care organizations; and partnerships, with other expert technical and creative entities, to improve the quality, efficiency, and acceptability of health promotion interventions.

  17. Designed to deter. Community barriers to physical activity for people with visual or motor impairments.

    Science.gov (United States)

    Kirchner, Corinne E; Gerber, Elaine G; Smith, Brooke C

    2008-04-01

    People with disabilities are more likely to be obese, in poor health, and get less physical activity than the general population. However, research on community factors for physical activity has generally either excluded most people with disabilities, or overlooked relevant factors of community accessibility. This exploratory study investigated environmental factors affecting people with motor impairments and people with visual impairments in urban neighborhoods. Quantitative and qualitative methods were used with a nonrandom sample (n=134) of users of four types of assistive mobility technologies: guide dogs, long canes, and motorized and manual wheelchairs. From July 2005 to August 2006, the sample participated in two telephone surveys. Between the surveys, a stratified random subsample (n =32) engaged in an ethnographic phase of observation and interviews. Most participants in all groups using assistive mobility technologies rated their neighborhoods as accessible, although they also reported many specific barriers. Users of assistive mobility technologies differed in the amount of reported physical activity and on specific barriers. Problems with sidewalk pavement and puddles/poor drainage were the most frequently mentioned environmental barriers, by 90% and 80%, respectively. Users of assistive mobility technologies were more similar on main strategies for dealing with barriers. All groups reported having to plan routes for outings, to alter planned routes, to go more slowly than planned, or to wait for a different time. Despite legislative requirements for accommodation, people with disabilities face barriers to physical activity, both in the built and social environments. Determined people with disabilities were able to overcome barriers, but required additional expenditure of resources to do so. Community design that can include people with disabilities requires detailed understanding of barriers specific both to types of impairments and to different types

  18. National energy ombudsman. 2013 activity report

    International Nuclear Information System (INIS)

    Gaubert, Jean; Merville, Denis; Lechevin, Bruno; Mialot, Stephane

    2014-06-01

    The National Energy Ombudsman is an independent administrative authority that was created by the law of 7 December 2006 relating to the energy sector, in preparation for the imminent liberalisation of the French gas and electricity markets. It has two legal roles: participating in the process of informing consumers about their rights, and recommending solutions for settling disputes. The Ombudsman reports directly to the French Parliament. This report summarizes the 2013 national energy ombudsman's activity in the domains of energy transition, conciliation between energy operators and consumers, consumers information, mediation, dispute settlement, markets opening, energy prices, quality of supply, smart meters, fight against energy poverty etc

  19. Quantitative data analysis of perceived barriers and motivators to physical activity in stroke survivors.

    Science.gov (United States)

    Nicholson, S L; Greig, C A; Sniehotta, F; Johnston, M; Lewis, S J; McMurdo, M E; Johnston, D; Scopes, J; Mead, G E

    2017-09-01

    Levels of physical activity after stroke are low, despite multiple health benefits. We explored stroke survivors' perceived barriers, motivators, self-efficacy and intention to physical activity. Fifty independently mobile stroke survivors were recruited prior to hospital discharge. Participants rated nine possible motivators and four possible barriers based on the Mutrie Scale, as having 'no influence', 'some influence' or 'a major influence' on physical activity. Participants also rated their self-efficacy and intention to increasing walking. The most common motivator was 'physical activity is good for health' [34 (68%)]. The most common barrier was 'feeling too tired' [24 (48%)]. Intention and self-efficacy were high. Self-efficacy was graded as either 4 or 5 (highly confident) on a five-point scale by [34 (68%)] participants, while 42 (84%) 'strongly agreed' or 'agreed' that they intended to increase their walking. Participants felt capable of increasing physical activity but fatigue was often perceived as a barrier to physical activity. This needs to be considered when encouraging stroke survivors to be more active.

  20. Overview Of The U.S. Department Of Energy And Nuclear Regulatory Commission Performance Assessment Approaches: Cementitious Barriers Partnership

    International Nuclear Information System (INIS)

    Langton, C.; Burns, H.

    2009-01-01

    a need to assess the behavior of cementitious materials for applications in environmental remediation and decontamination and decommissioning (D and D) applications. The ability to assess the use and benefits of cementitious materials for these applications can significantly affect decisions related to cleanup activities. For example the need for costly remedial actions may not be necessary if existing or new cementitious barriers were adequately represented. The sections dealing with regulatory considerations include summaries of the different regulations that are relevant for various applications involving cementitious materials. A summary of regulatory guidance and/or policies pertaining to performance assessment of cementitious materials and sensitivity and uncertainty analyses is also provided in the following chapters. Numerous examples of specific applications are provided in each report. The examples are organized into traditional waste disposal applications (performance assessments), applications related to environmental remediation and D and D, and reactor and spent fuel related assessments. Sections that discuss specific facilities or sites contain: (1) descriptions of the role of the cementitious barriers or sensitivity/uncertainty analysis, (2) parameter assumptions and conceptual models, and (3) a relative discussion of the significance in the context of the assessment. Examples from both the U.S. Department of Energy Sites and the U.S. Nuclear Regulatory Commission are provided to illustrate the variety of applications and approaches that have been used. In many cases, minimal credit was taken for cementitious barriers. However, in some of those cases, benefits of being able to take credit for barriers were identified. The examples included: (1) disposal facilities (vaults, trenches, tank closures, cementitious waste forms and containers, etc.), (2) environmental remediation (old disposal facilities), (3) reactor and large structure decommissioning

  1. OVERVIEW OF THE U.S. DEPARTMENT OF ENERGY AND NUCLEAR REGULATORY COMMISSION PERFORMANCE ASSESSMENT APPROACHES: CEMENTITIOUS BARRIERS PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C.; Burns, H.

    2009-05-29

    a need to assess the behavior of cementitious materials for applications in environmental remediation and decontamination and decommissioning (D&D) applications. The ability to assess the use and benefits of cementitious materials for these applications can significantly affect decisions related to cleanup activities. For example the need for costly remedial actions may not be necessary if existing or new cementitious barriers were adequately represented. The sections dealing with regulatory considerations include summaries of the different regulations that are relevant for various applications involving cementitious materials. A summary of regulatory guidance and/or policies pertaining to performance assessment of cementitious materials and sensitivity and uncertainty analyses is also provided in the following chapters. Numerous examples of specific applications are provided in each report. The examples are organized into traditional waste disposal applications (performance assessments), applications related to environmental remediation and D&D, and reactor and spent fuel related assessments. Sections that discuss specific facilities or sites contain: (1) descriptions of the role of the cementitious barriers or sensitivity/uncertainty analysis, (2) parameter assumptions and conceptual models, and (3) a relative discussion of the significance in the context of the assessment. Examples from both the U.S. Department of Energy Sites and the U.S. Nuclear Regulatory Commission are provided to illustrate the variety of applications and approaches that have been used. In many cases, minimal credit was taken for cementitious barriers. However, in some of those cases, benefits of being able to take credit for barriers were identified. The examples included: (1) disposal facilities (vaults, trenches, tank closures, cementitious waste forms and containers, etc.), (2) environmental remediation (old disposal facilities), (3) reactor and large structure decommissioning, and (4

  2. Universal trend for heavy-ion total reaction cross sections at energies above the Coulomb barrier

    International Nuclear Information System (INIS)

    Tavares, O.A.P.; Medeiros, E.L.; Morcelle, V.

    2010-06-01

    Heavy-ion total reaction cross section measurements for more than one thousand one hundred reaction cases covering 61 target nuclei in the range 6 Li- 238 U, and 158 projectile nuclei from 2 H up to 84 Kr (mostly exotic ones) have been analysed in a systematic way by using an empirical, three-parameter formula which is applicable to cases for projectile kinetic energies above the Coulomb barrier. The analysis has shown that the average total nuclear binding energy per nucleon of the interacting nuclei and their radii are the chief quantities which describe the cross section patterns. A great number of cross section data (87%) has been quite satisfactorily reproduced by the proposed formula, therefore total reaction cross section predictions for new, not yet experimentally investigated reaction cases can be obtained within 25 percent (or much less) of uncertainty (author)

  3. Universal trend for heavy-ion total reaction cross sections at energies above the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O.A.P.; Medeiros, E.L., E-mail: emil@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Morcelle, V. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2010-06-15

    Heavy-ion total reaction cross section measurements for more than one thousand one hundred reaction cases covering 61 target nuclei in the range {sup 6}Li-{sup 238}U, and 158 projectile nuclei from {sup 2}H up to {sup 84}Kr (mostly exotic ones) have been analysed in a systematic way by using an empirical, three-parameter formula which is applicable to cases for projectile kinetic energies above the Coulomb barrier. The analysis has shown that the average total nuclear binding energy per nucleon of the interacting nuclei and their radii are the chief quantities which describe the cross section patterns. A great number of cross section data (87%) has been quite satisfactorily reproduced by the proposed formula, therefore total reaction cross section predictions for new, not yet experimentally investigated reaction cases can be obtained within 25 percent (or much less) of uncertainty (author)

  4. Gaps, barriers and conceptual chasms: theories of technology transfer and energy in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Shove, E. [University of Lancaster (United Kingdom). Centre for the Study of Environmental Change

    1998-12-01

    Having shown how much energy might be saved through the use of economically worthwhile measures and technologies, researchers and policy makers then find themselves trying to close the gap between current practice and recognised technical potential. The ensuing process of technology transfer is often seen as a process of overcoming 'non technical barriers' which inhibit the realisation of proven technical potential. This familiar approach depends upon a strong conceptual distinction between the social, on the one hand, and the technical, on the other. But does it make sense to talk of technical potential in the abstract? Do people really have technologies 'transferred' upon them? Drawing upon ideas from the sociology of science and technology and on recent research funded by Britain's Economic and Social Research Council, this paper unpacks conventional beliefs about the diffusion of energy efficient technologies and suggests an alternative approach which acknowledges the social structuring of technical innovation. (author)

  5. Some peculiarities of interactions of weakly bound lithium nuclei at near-barrier energies

    Science.gov (United States)

    Kabyshev, A. M.; Kuterbekov, K. A.; Sobolev, Yu G.; Penionzhkevich, Yu E.; Kubenova, M. M.; Azhibekov, A. K.; Mukhambetzhan, A. M.; Lukyanov, S. M.; Maslov, V. A.; Kabdrakhimova, G. D.

    2018-02-01

    This paper presents new experimental data on the total cross sections of 9Li + 28Si reactions at low energies as well as the analysis of previously obtained data for 6,7Li. Based on a large collection of data (authors’ and literature data) we carried out a comparative analysis of the two main experimental interaction cross sections (angular distributions of the differential cross sections and total reaction cross sections) for weakly bound lithium (6-9Li, 11Li) nuclei in the framework of Kox parameterization and the macroscopic optical model. We identified specific features of these interactions and predicted the experimental trend in the total reaction cross sections for Li isotopes at energies close to the Coulomb barrier.

  6. Deuteron interaction with 124Sn nuclei at sub-barrier energies

    Directory of Open Access Journals (Sweden)

    Yu.N. Pavlenko

    2015-04-01

    Full Text Available The measurements of cross sections for deuteron elastic scattering and (d,p reaction on 124Sn nuclei have been performed with aim to study the features of sub-barrier deuteron interaction with heavy nuclei. Experimental data were obtained on the electrostatic Tandem accelerator EGP-10K of the Institute for Nuclear Research (Kyiv at the deuteron beam energies Ed = 4.0; 5.0 and 5.5 MeV. Cross sections of deuteron elastic scattering were calculated in approach where the deuteron interaction potential with heavy nuclei at sub-barrier energies has been constructed in the framework of single folding model using the complex dynamic polarization potential. It is shown that the account of finite deuteron size leads to the increasing the nuclear potential in outer region of interaction and significantly improves the description of the experimental data. The calculations of elastic scattering cross sections were performed without any variations of the nuclear potential parameters. The analysis of measured integral cross sections of the 124Sn(d,p reaction and calculated cross sections of deuteron breakup reaction 124Sn(d,pn124Sn shows the dominant contribution of the neutron transfer reaction in the processes of the formation of protons and elastic scattering cross sections.

  7. Hindrance of O16+Pb208 fusion at extreme sub-barrier energies

    Science.gov (United States)

    Esbensen, Henning; Mişicu, Şerban

    2007-11-01

    We analyze the fusion data for O16+Pb208 using coupled-channels calculations. We include couplings to the low-lying surface excitations of the projectile and target and study the effect of the (O16,O17) one-neutron pickup. The hindrance of the fusion data that is observed at energies far below the Coulomb barrier cannot be explained by a conventional ion-ion potential and defining the fusion in terms of ingoing-wave boundary conditions (IWBC). We show that the hindrance can be explained fairly well by applying the M3Y double-folding potential which has been corrected with a calibrated, repulsive term that simulates the effect of nuclear incompressibility. We show that the coupling to one-neutron transfer channels plays a crucial role in improving the fit to the data. The best fit is achieved by increasing the transfer strength by 25% relative to the strength that is required to reproduce the one-neutron transfer data. The larger strength is not unrealistic because the calculated inelastic plus transfer cross section is in good agreement with the measured quasielastic cross section. We finally discuss the problem of reproducing the fusion data at energies far above the Coulomb barrier. Here we do not account for the data when we apply the IWBC but the discrepancy is essentially eliminated by applying the M3Y+repulsion potential and a weak, short-ranged imaginary potential.

  8. Condensation on superhydrophobic surfaces: the role of local energy barriers and structure length scale.

    Science.gov (United States)

    Enright, Ryan; Miljkovic, Nenad; Al-Obeidi, Ahmed; Thompson, Carl V; Wang, Evelyn N

    2012-10-09

    Water condensation on surfaces is a ubiquitous phase-change process that plays a crucial role in nature and across a range of industrial applications, including energy production, desalination, and environmental control. Nanotechnology has created opportunities to manipulate this process through the precise control of surface structure and chemistry, thus enabling the biomimicry of natural surfaces, such as the leaves of certain plant species, to realize superhydrophobic condensation. However, this "bottom-up" wetting process is inadequately described using typical global thermodynamic analyses and remains poorly understood. In this work, we elucidate, through imaging experiments on surfaces with structure length scales ranging from 100 nm to 10 μm and wetting physics, how local energy barriers are essential to understand non-equilibrium condensed droplet morphologies and demonstrate that overcoming these barriers via nucleation-mediated droplet-droplet interactions leads to the emergence of wetting states not predicted by scale-invariant global thermodynamic analysis. This mechanistic understanding offers insight into the role of surface-structure length scale, provides a quantitative basis for designing surfaces optimized for condensation in engineered systems, and promises insight into ice formation on surfaces that initiates with the condensation of subcooled water.

  9. Regulatory barriers for activating flexibility in the Nordic-Baltic electricity market

    DEFF Research Database (Denmark)

    Bergaentzlé, Claire; Skytte, Klaus; Soysal, Emilie Rosenlund

    2017-01-01

    to flexibility. We find that the most restrictive barriers against flexibility are emitted by public authorities as part of broader policy strategies. Overall, we find that current regulatory and market framework conditions do not hinder flexibility. However, despite that, flexibility remains limited due......, load adjustment or to a greater coupling to other energy sectors. In this paper, we identify the framework conditions that influence the provision of VRE-friendly flexibility in the Nordic and Baltic electricity sector, i.e., the market and regulatory settings that act as drivers or barriers...... to a lack of coherent instruments intended to both the demand and supply-side to effectively act flexibly....

  10. A Review of Barriers to and Opportunities for the Integration of Renewable Energy in the Southeast

    Energy Technology Data Exchange (ETDEWEB)

    McConnell, Ben W [ORNL; Hadley, Stanton W [ORNL; Xu, Yan [ORNL

    2011-08-01

    The objectives of this study were to prepare a summary report that examines the opportunities for and obstacles to the integration of renewable energy resources in the Southeast between now and the year 2030. The report, which is based on a review of existing literature regarding renewable resources in the Southeast, includes the following renewable energy resources: wind, solar, hydro, geothermal, biomass, and tidal. The evaluation was conducted by the Oak Ridge National Laboratory for the Energy Foundation and is a subjective review with limited detailed analysis. However, the report offers a best estimate of the magnitude, time frame, and cost of deployment of renewable resources in the Southeast based upon the literature reviewed and reasonable engineering and economic estimates. For the purposes of this report, the Southeast is defined as the states of Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, and West Virginia. In addition, some aspects of the report (wind and geothermal) also consider the extended Southeast, which includes Maryland, Missouri, Oklahoma, and Texas. A description of the existing base of renewable electricity installations in the region is given for each technology considered. Where available, the possible barriers and other considerations regarding renewable energy resources are listed in terms of availability, investment and maintenance costs, reliability, installation requirements, policies, and energy market. As stated above, the report is a comprehensive review of renewable energy resources in the southeastern region of United States based on a literature study that included information obtained from the Southern Bio-Power wiki, sources from the Energy Foundation, sources available to ORNL, and sources found during the review. The report consists of an executive summary, this introductory chapter describing report objectives, a chapter on analysis methods and

  11. Characterization of a dielectric barrier discharge in contact with liquid and producing a plasma activated water

    Science.gov (United States)

    Neretti, G.; Taglioli, M.; Colonna, G.; Borghi, C. A.

    2017-01-01

    In this work a low-temperature plasma source for the generation of plasma activated water (PAW) is developed and characterized. The plasma reactor was operated by means of an atmospheric-pressure air dielectric barrier discharge (DBD). The plasma generated is in contact with the water surface and is able to chemically activate the liquid medium. Electrodes were supplied by both sinusoidal and nanosecond-pulsed voltage waveforms. Treatment times were varied from 2 to 12 min to increase the energy dose released to the water by the DBD plasma. The physics of the discharge was studied by means of electrical, spectroscopic and imaging diagnostics. The interaction between the plasma and the liquid was investigated as well. Temperature and composition of the treated water were detected. Images of the discharges showed a filamentary behaviour in the sinusoidal case and a more homogeneous behaviour in the nanosecond-pulsed one. The images and the electrical measurements allowed to evaluate an average electron number density of about 4  ×  1019 and 6  ×  1017 m-3 for the sinusoidal and nanosecond-pulsed discharges respectively. Electron temperatures in the range of 2.1÷2.6 eV were measured by using spectroscopic diagnostics. Rotational temperatures in the range of 318-475 K were estimated by fitting synthetic spectra with the measured ones. Water temperature and pH level did not change significantly after the exposure to the DBD plasma. The production of ozone and hydrogen peroxide within the water was enhanced by increasing the plasma treatment time and the energy dose. Numerical simulations of the nanosecond-pulsed discharge were performed by using a self-consistent coupling of state-to-state kinetics of the air mixture with the Boltzmann equation of free electron kinetics. Temporal evolution of the electron energy distribution function shows departure from the Maxwellian distribution especially during the afterglow phase of the discharge. When

  12. Predictors of physical activity and barriers to exercise in nursing and medical students.

    Science.gov (United States)

    Blake, Holly; Stanulewicz, Natalia; Mcgill, Francesca

    2017-04-01

    To investigate physical activity levels of nursing and medicine students, examine predictors of physical activity level and examine the most influential benefits and barriers to exercise. Healthcare professionals have low levels of physical activity, which increases their health risk and may influence their health promotion practices with patients. We surveyed 361 nursing (n = 193) and medicine (n = 168) students studying at a UK medical school. Questionnaire survey, active over 12 months in 2014-2015. Measures included physical activity level, benefits and barriers to exercise, social support, perceived stress and self-efficacy for exercise. Many nursing and medicine students did not achieve recommended levels of physical activity (nursing 48%; medicine 38%). Perceived benefits of exercise were health related, with medicine students identifying additional benefits for stress relief. Most notable barriers to exercise were as follows: lack of time, facilities having inconvenient schedules and exercise not fitting around study or placement schedules. Nursing students were less active than medicine students; they perceived fewer benefits and more barriers to exercise and reported lower social support for exercise. Physical activity of nursing and medicine students was best predicted by self-efficacy and social support, explaining 35% of the variance. Physical activity should be promoted in nursing and medicine students. Interventions should aim to build self-efficacy for exercise and increase social support. Interventions should be developed that are targeted specifically to shift-working frontline care staff, to reduce schedule-related barriers to exercise and to increase accessibility to workplace health and well-being initiatives. © 2016 John Wiley & Sons Ltd.

  13. Activation barriers for series of exothermic homologous reactions. VI. Reactions of lanthanide and transition metal atoms.

    Science.gov (United States)

    Blue, Alan S.; Fontijn, Arthur

    2001-09-01

    Semiempirical configuration interaction (SECI) theory to predict activation barriers, E, as given by k(T)=ATn exp(-E(RT), has been applied to homologous series of lanthanide (LN) and transition metal (TM) atom oxidation reactions. This was achieved by considering as homologous series reactions of elements differing only by the number of electrons in one subshell. Comparison between SECI and experimental results leads to an average deviation for the LN+N2O reactions of 0.66 kJ mol-1, and up to 5.5 kJ mol-1 for other series. Thirty-one activation barriers are reported.

  14. Redox-active media for permeable reactive barriers

    International Nuclear Information System (INIS)

    Sivavec, T.M.; Mackenzie, P.D.; Horney, D.P.; Baghel, S.S.

    1997-01-01

    In this paper, three classes of redox-active media are described and evaluated in terms of their long-term effectiveness in treating TCE-contaminated groundwater in permeable reactive zones. Zero-valent iron, in the form of recycled cast iron filings, the first class, has received considerable attention as a reactive media and has been used in about a dozen pilot- and full-scale subsurface wall installations. Criteria used in selecting commercial sources of granular iron, will be discussed. Two other classes of redox-active media that have not yet seen wide use in pilot- or full-scale installations will also be described: Fe(II) minerals and bimetallic systems. Fe(II) minerals, including magnetite (Fe 3 O 4 ), and ferrous sulfide (troilite, FeS), are redox-active and afford TCE reduction rates and product distributions that suggest that they react via a reductive mechanism similar to that which operates in the FeO system. Fe(II) species within the passive oxide layer coating the iron metal may act as electron transfer mediators, with FeO serving as the bulk reductant. Bimetallic systems, the third class of redox-active media, are commonly prepared by plating a second metal onto zero-valent iron (e.g., Ni/Fe and Pd/Fe) and have been shown to accelerate solvent degradation rates relative to untreated iron metal. The long-term effectiveness of this approach, however, has not yet been determined in groundwater treatability tests. The results of a Ni-plated iron column study using site groundwater indicate that a change in reduction mechanism (to catalytic dehydrohalogenation/hydrogenation) accounts for the observed rate enhancement. A significant loss in media reactivity was observed over time, attributable to Ni catalyst deactivation or poisoning. Zero-valent iron systems have not shown similar losses in reactivity in long-term laboratory, pilot or field investigations

  15. Physical activity barriers and enablers in older Veterans with lower-limb amputation.

    Science.gov (United States)

    Littman, Alyson J; Boyko, Edward J; Thompson, Mary Lou; Haselkorn, Jodie K; Sangeorzan, Bruce J; Arterburn, David E

    2014-01-01

    Little is known about the types of physical activities that older individuals with lower-limb loss perform, correlates of regular physical activity (PA), and barriers and facilitators to PA. We conducted an exploratory study in 158 older Veterans from the Pacific Northwest with a partial foot (35%), below-knee (39%) and above-knee (26%) amputation. Ninety-eight percent of survey respondents were male, on average 65 yr of age and 15 yr postamputation; 36% of amputations were trauma-related. The most commonly reported physical activities were muscle strengthening (42%), yard work and/or gardening (30%), and bicycling (11%). Forty-three percent were classified as physically active based on weekly moderate- and vigorous-intensity PA. History of vigorous preamputation PA was positively associated with being active, while low wealth and watching ≥5 h/d of television/videos were inversely associated. While pain- and resource-related barriers to PA were most frequently reported, only knowledge-related and interest/motivation-related barriers were inversely associated with being active. Family support and financial assistance to join a gym were the most commonly reported factors that would facilitate PA. To increase PA in the older amputee population, interventions should address motivational issues, knowledge gaps, and television watching; reduce financial barriers to exercising; and consider involving family members.

  16. Motivators and barriers for physical activity in the oldest old: a systematic review.

    Science.gov (United States)

    Baert, Veerle; Gorus, Ellen; Mets, Tony; Geerts, Christel; Bautmans, Ivan

    2011-09-01

    Worldwide, people engage insufficiently in physical activity, particularly subjects aged 80 years and over. For optimal life-style campaigns, knowledge of motivators and barriers for physical activity is mandatory. Given their specific needs, it is conceivable that these would be different for the oldest old compared to younger subjects. Pubmed, Web of Science and Psychinfo were systematically screened for articles reporting motivators and barriers for physical activity. Papers were excluded if data regarding elderly aged >79 years were absent. Forty-four relevant articles were included, involving a total of 28,583 subjects. Sixty one motivators and 59 barriers for physical activity in the elderly were identified, including those who are relevant for persons aged 80 years and over. Based on the results of our literature review, we recommend that when promoting physical activity in the oldest old, special attention is paid to the health benefits of physical activity, to the subject's fears, individual preferences and social support, and to constraints related to the physical environment. However, no studies were found exclusively describing people aged 80 years and over, and future research is necessary to differentiate the barriers or motivators that are specific for the oldest old from those of younger elderly. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. PATTERNS OF PHYSICAL ACTIVITY AMONG AMERICAN INDIAN CHILDREN: AN ASSESSMENT OF BARRIERS AND SUPPORT

    Science.gov (United States)

    Thompson, Janice L.; Davis, Sally M.; Gittelsohn, Joel; Going, Scott; Becenti, Alberta; Metcalfe, Lauve; Stone, Elaine; Harnack, Lisa; Ring, Kim

    2016-01-01

    Estimates indicate that 10% to 50% of American Indian and non-Indian children in the U.S. are obese, defined as a body mass index ≥ 95th percentile of the NHANES II reference data. Pathways is a two-phase, multi-site study to develop and test a school-based obesity prevention program in American Indian schoolchildren in grades three through five. During Phase I feasibility prior to initiation of the Pathways trial, data were collected related to physical activity patterns, and the supports of, and barriers to, physical activity. Nine schools from communities representing six different tribal groups participated in this study. Multiple measures were used for data collection including direct observation, paired child interviews, and in-depth interviews and focus groups with adults. Students completed the self-administered Knowledge, Attitudes, and Behaviors (KAB) survey, and a Physical Activity Questionnaire (PAQ). Barriers to physical activity at schools included a lack of facilities, equipment, and trained staff persons for PE. Adults were not consistently active with their children, but they were highly supportive of their children’s activity level. Children reported a strong enjoyment of physical activity and strong peer support to be physically active. Weather conditions, safety concerns, and homework/chores were common barriers to physical activity reported by children and adult caregivers. The information was used to design culturally and age-appropriate, practical interventions including the five physical activity programs for schoolchildren in the Pathways study. PMID:11759094

  18. Physical activity in hypertrophic cardiomyopathy: prevalence of inactivity and perceived barriers

    Science.gov (United States)

    Sweeting, Joanna; Ingles, Jodie; Timperio, Anna; Patterson, Jillian; Ball, Kylie; Semsarian, Christopher

    2016-01-01

    Objectives This study aimed to determine the prevalence of physical inactivity and perceived barriers to physical activity among individuals with hypertrophic cardiomyopathy (HCM), and to determine potential demographic, clinical and health-related factors influencing likelihood of meeting physical activity guidelines. Methods This was a cross-sectional study of consecutive patients (n=198) with HCM attending a specialist HCM centre from July 2014 to November 2015. The primary outcome measure was physical activity (minutes per day), as measured by self-report (International Physical Activity Questionnaire (IPAQ)) and objective means (ActiGraph accelerometer). For both, participants were classified as meeting guidelines if they did at least 150 min per week of physical activity. Quality of life (Short Form-36 V.2, SF-36v2), barriers to exercise and clinical–demographic data were also collected. Results In total, 54.8% of participants did not meet physical activity recommendations based on IPAQ, and 12.7% did not meet guidelines based on accelerometer data. The most commonly identified barriers to exercise were ‘pain interferes with my exercise’ (33%) and ‘I have an injury/disability that stops me’ (29%). Independent factors associated with meeting guidelines included older age (OR 0.66, 95% CI 0.51 to 0.85, p=0.002), higher education level (OR 2.31, 95% CI 1.08 to 4.93, p=0.03), better physical quality of life (OR 1.05, 95% CI 1.0 to 1.09, p=0.05) and more reported barriers (OR 0.71, 95% CI 0.56 to 0.91, p=0.01). Conclusions More than half of the patients with HCM did not meet minimum physical activity recommendations. Several barriers to exercise among individuals with HCM exist, and provide the basis for targeted interventions to promote physical activity and improve overall health in patients with HCM. PMID:27547438

  19. Activation of RhoA, but Not Rac1, Mediates Early Stages of S1P-Induced Endothelial Barrier Enhancement.

    Science.gov (United States)

    Zhang, Xun E; Adderley, Shaquria P; Breslin, Jerome W

    2016-01-01

    Compromised endothelial barrier function is a hallmark of inflammation. Rho family GTPases are critical in regulating endothelial barrier function, yet their precise roles, particularly in sphingosine-1-phosphate (S1P)-induced endothelial barrier enhancement, remain elusive. Confluent cultures of human umbilical vein endothelial cells (HUVEC) or human dermal microvascular endothelial cells (HDMEC) were used to model the endothelial barrier. Barrier function was assessed by determining the transendothelial electrical resistance (TER) using an electrical cell-substrate impedance sensor (ECIS). The roles of Rac1 and RhoA were tested in S1P-induced barrier enhancement. The results show that pharmacologic inhibition of Rac1 with Z62954982 failed to block S1P-induced barrier enhancement. Likewise, expression of a dominant negative form of Rac1, or knockdown of native Rac1 with siRNA, failed to block S1P-induced elevations in TER. In contrast, blockade of RhoA with the combination of the inhibitors Rhosin and Y16 significantly reduced S1P-induced increases in TER. Assessment of RhoA activation in real time using a fluorescence resonance energy transfer (FRET) biosensor showed that S1P increased RhoA activation primarily at the edges of cells, near junctions. This was complemented by myosin light chain-2 phosphorylation at cell edges, and increased F-actin and vinculin near intercellular junctions, which could all be blocked with pharmacologic inhibition of RhoA. The results suggest that S1P causes activation of RhoA at the cell periphery, stimulating local activation of the actin cytoskeleton and focal adhesions, and resulting in endothelial barrier enhancement. S1P-induced Rac1 activation, however, does not appear to have a significant role in this process.

  20. Activation of RhoA, but Not Rac1, Mediates Early Stages of S1P-Induced Endothelial Barrier Enhancement.

    Directory of Open Access Journals (Sweden)

    Xun E Zhang

    Full Text Available Compromised endothelial barrier function is a hallmark of inflammation. Rho family GTPases are critical in regulating endothelial barrier function, yet their precise roles, particularly in sphingosine-1-phosphate (S1P-induced endothelial barrier enhancement, remain elusive. Confluent cultures of human umbilical vein endothelial cells (HUVEC or human dermal microvascular endothelial cells (HDMEC were used to model the endothelial barrier. Barrier function was assessed by determining the transendothelial electrical resistance (TER using an electrical cell-substrate impedance sensor (ECIS. The roles of Rac1 and RhoA were tested in S1P-induced barrier enhancement. The results show that pharmacologic inhibition of Rac1 with Z62954982 failed to block S1P-induced barrier enhancement. Likewise, expression of a dominant negative form of Rac1, or knockdown of native Rac1 with siRNA, failed to block S1P-induced elevations in TER. In contrast, blockade of RhoA with the combination of the inhibitors Rhosin and Y16 significantly reduced S1P-induced increases in TER. Assessment of RhoA activation in real time using a fluorescence resonance energy transfer (FRET biosensor showed that S1P increased RhoA activation primarily at the edges of cells, near junctions. This was complemented by myosin light chain-2 phosphorylation at cell edges, and increased F-actin and vinculin near intercellular junctions, which could all be blocked with pharmacologic inhibition of RhoA. The results suggest that S1P causes activation of RhoA at the cell periphery, stimulating local activation of the actin cytoskeleton and focal adhesions, and resulting in endothelial barrier enhancement. S1P-induced Rac1 activation, however, does not appear to have a significant role in this process.

  1. Understanding exercise self-efficacy and barriers to leisure-time physical activity among postnatal women.

    Science.gov (United States)

    Cramp, Anita G; Bray, Steven R

    2011-07-01

    Studies have demonstrated that postnatal women are at high risk for physical inactivity and generally show lower levels of leisure-time physical activity (LTPA) compared to prepregnancy. The overall purpose of the current study was to investigate social cognitive correlates of LTPA among postnatal women during a 6-month period following childbirth. A total of 230 women (mean age = 30.9) provided descriptive data regarding barriers to LTPA and completed measures of LTPA and self-efficacy (exercise and barrier) for at least one of the study data collection periods. A total of 1,520 barriers were content analyzed. Both exercise and barrier self-efficacy were positively associated with subsequent LTPA. Exercise self-efficacy at postnatal week 12 predicted LTPA from postnatal weeks 12 to 18 (β = .40, R (2) = .18) and exercise self-efficacy at postnatal week 24 predicted LTPA during weeks 24-30 (β = .49, R (2) = .30). Barrier self-efficacy at week 18 predicted LTPA from weeks 18 to 24 (β = .33, R (2) = .13). The results of the study identify a number of barriers to LTPA at multiple time points closely following childbirth which may hinder initiation, resumption or maintenance of LTPA. The results also suggest that higher levels of exercise and barrier self-efficacy are prospectively associated with higher levels of LTPA in the early postnatal period. Future interventions should be designed to investigate causal effects of developing participants' exercise and barrier self-efficacy for promoting and maintaining LTPA during the postnatal period.

  2. The free energy barrier for arginine gating charge translation is altered by mutations in the voltage sensor domain.

    Directory of Open Access Journals (Sweden)

    Christine S Schwaiger

    Full Text Available The gating of voltage-gated ion channels is controlled by the arginine-rich S4 helix of the voltage-sensor domain moving in response to an external potential. Recent studies have suggested that S4 moves in three to four steps to open the conducting pore, thus visiting several intermediate conformations during gating. However, the exact conformational changes are not known in detail. For instance, it has been suggested that there is a local rotation in the helix corresponding to short segments of a 3(10-helix moving along S4 during opening and closing. Here, we have explored the energetics of the transition between the fully open state (based on the X-ray structure and the first intermediate state towards channel closing (C1, modeled from experimental constraints. We show that conformations within 3 Å of the X-ray structure are obtained in simulations starting from the C1 model, and directly observe the previously suggested sliding 3(10-helix region in S4. Through systematic free energy calculations, we show that the C1 state is a stable intermediate conformation and determine free energy profiles for moving between the states without constraints. Mutations indicate several residues in a narrow hydrophobic band in the voltage sensor contribute to the barrier between the open and C1 states, with F233 in the S2 helix having the largest influence. Substitution for smaller amino acids reduces the transition cost, while introduction of a larger ring increases it, largely confirming experimental activation shift results. There is a systematic correlation between the local aromatic ring rotation, the arginine barrier crossing, and the corresponding relative free energy. In particular, it appears to be more advantageous for the F233 side chain to rotate towards the extracellular side when arginines cross the hydrophobic region.

  3. Barriers to Zero Energy Construction (ZEC); technically possible; why not succeed yet?

    NARCIS (Netherlands)

    Abdalla, G.; Maas, G.J.; Demers, C.M.H.; Potvin, A

    2009-01-01

    The construction activities have a significant impact on the environment in terms of energy consumption and use of raw materials. The construction industry has been challenged to meet the human needs in environmentally friendly ways. Environmentally friendly measures and proven renewable energy

  4. Predictors of physical activity and barriers to exercise in nursing and medical students

    OpenAIRE

    Blake, Holly; Stanulewicz, Natalia; McGill, Francesca

    2016-01-01

    Aims\\ud \\ud To investigate physical activity levels of nursing and medicine students; examine predictors of physical activity level; and examine the most influential benefits and barriers to exercise.\\ud Background\\ud \\ud Healthcare professionals have low levels of physical activity, which increases their health risk and may influence their health promotion practices with patients.\\ud Design\\ud \\ud We surveyed 361 nursing (n=193) and medicine (n=168) students studying at a UK medical school.\\...

  5. Hybrid energy harvesting using active thermal backplane

    Science.gov (United States)

    Kim, Hyun-Wook; Lee, Dong-Gun

    2016-04-01

    In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

  6. Exploring the facilitators and barriers to engagement in physical activity for people with multiple sclerosis.

    Science.gov (United States)

    Kayes, Nicola M; McPherson, Kathryn M; Schluter, Philip; Taylor, Denise; Leete, Marta; Kolt, Gregory S

    2011-01-01

    To explore the relationship that cognitive behavioural and other previously identified variables have with physical activity engagement in people with multiple sclerosis (MS). This study adopted a cross-sectional questionnaire design. Participants were 282 individuals with MS. Outcome measures included the Physical Activity Disability Survey--Revised, Cognitive and Behavioural Responses to Symptoms Questionnaire, Barriers to Health Promoting Activities for Disabled Persons Scale, Multiple Sclerosis Self-efficacy Scale, Self-Efficacy for Chronic Diseases Scales and Chalder Fatigue Questionnaire. Multivariable stepwise regression analyses found that greater self-efficacy, greater reported mental fatigue and lower number of perceived barriers to physical activity accounted for a significant proportion of variance in physical activity behaviour, over that accounted for by illness-related variables. Although fear-avoidance beliefs accounted for a significant proportion of variance in the initial analyses, its effect was explained by other factors in the final multivariable analyses. Self-efficacy, mental fatigue and perceived barriers to physical activity are potentially modifiable variables which could be incorporated into interventions designed to improve physical activity engagement. Future research should explore whether a measurement tool tailored to capture beliefs about physical activity identified by people with MS would better predict participation in physical activity.

  7. Barriers, Motivations, and Preferences for Physical Activity Among Female African American Older Adults.

    Science.gov (United States)

    Gothe, Neha P; Kendall, Bradley J

    2016-01-01

    According to the Centers for Disease Control and Prevention, less than 11% of adults more than the age of 65 meet the 2008 Physical Activity Guidelines for Americans. Among minority populations, only 5% of non-Hispanic Black older adults met the guidelines. Given our limited understanding of psychosocial and environmental factors that affect physical activity participation in these groups, the purpose of our focus groups was to investigate barriers, motivators, and preferences of physical activity for community-dwelling African American older adults. Three focus groups were conducted with female African American older adults ( N = 20). Questions posed to each focus group targeted motivations and barriers toward physical activity as well as their preferences for physical activity. The motivations included perceived health benefits of physical activity, social support, and enjoyment associated with engagement in physical activity. Prominent barriers included time and physical limitations, peer pressure and family responsibilities, and weather and poor neighborhood conditions. Group activities involving a dance component and novel exercises such as tai-chi or yoga were preferred choices. These findings should be taken into consideration when designing and implementing research or community physical activity programs for female African American older adults.

  8. Barriers, Motivations, and Preferences for Physical Activity Among Female African American Older Adults

    Directory of Open Access Journals (Sweden)

    Neha P. Gothe PhD

    2016-11-01

    Full Text Available According to the Centers for Disease Control and Prevention, less than 11% of adults more than the age of 65 meet the 2008 Physical Activity Guidelines for Americans. Among minority populations, only 5% of non-Hispanic Black older adults met the guidelines. Given our limited understanding of psychosocial and environmental factors that affect physical activity participation in these groups, the purpose of our focus groups was to investigate barriers, motivators, and preferences of physical activity for community-dwelling African American older adults. Three focus groups were conducted with female African American older adults ( N = 20. Questions posed to each focus group targeted motivations and barriers toward physical activity as well as their preferences for physical activity. The motivations included perceived health benefits of physical activity, social support, and enjoyment associated with engagement in physical activity. Prominent barriers included time and physical limitations, peer pressure and family responsibilities, and weather and poor neighborhood conditions. Group activities involving a dance component and novel exercises such as tai-chi or yoga were preferred choices. These findings should be taken into consideration when designing and implementing research or community physical activity programs for female African American older adults.

  9. Argentine nuclear energy standardization activities

    International Nuclear Information System (INIS)

    Boero, Norma; Corcuera, Roberto; Palacios, Tulio A.; Hey, Alfredo M.; Berte, G.; Trama, L.

    2004-01-01

    The International Organization for Standardization (ISO) has more than 200 Technical Committees that develop technical standards. During April 2004 took place in Buenos Aires the 14th Plenary of the ISO/TC 85 Nuclear Energy Committee. During this Plenary issues as Nuclear Terminology, Radiation Protection, Nuclear Fuels, Nuclear Reactors and Irradiation Dosimetry was dealt with. 105 International delegates and 45 National delegates (belonging to CNEA, ARN, NASA, INVAP, CONUAR, IONICS and other organizations) attended the meetings. During this meeting ISO/TC 85 changed its scope; the new scope of the Committee is 'Standardization in the fields of peaceful applications of nuclear energy and of the protection of individuals against all sources of ionizing radiations'. This work summarizes the most important advances and resolutions about the development of standards taken during this meeting as well as the main conclusions. (author) [es

  10. Passive House and Low Energy Buildings: Barriers and Opportunities for Future Development within UK Practice

    Directory of Open Access Journals (Sweden)

    Adrian Pitts

    2017-02-01

    Full Text Available This paper describes research carried out to understand better the current and future emphases emerging from practice for the design and development of “Passive House” and low energy buildings. The paper initially discusses the extant position, particularly with regards to the UK and considers how regulation and assessment systems have changed in recent years, as well as projecting ideas forward taking account of contemporary political situations. Relevant previous research into Passive House and low energy design and construction is then reviewed. The need for greater understanding of professionals and their communication/collaboration with clients were identified as important factors impacting development. Those involved in the design and construction practice therefore have key roles in the process of enhancing energy efficiency. Five industry/practice based professional organizations were interviewed in-depth to gain insights into their experience of current low energy design, and to extrapolate the outcomes to future scenarios. The method employed used a structured interview technique with key question areas to lead the discussion. The anonymized responses discussed are grouped around key themes. Evidence suggests there has been a move towards the adoption of voluntary high level standards because of potential limitations with mandatory regulations and because of perceived additional benefits of higher quality design. This change is now more than previously, being driven by informed clients, design professionals, and the industry, with regulation taking a secondary role. New opportunities and barriers are becoming evident and these require further consideration.

  11. Global Account of Barriers and Facilitators of Physical Activity Among Patients with Diabetes Mellitus: A Narrative Review of the Literature.

    Science.gov (United States)

    Adeniyi, Ade F; Anjana, Ranjit M; Weber, Mary B

    2016-01-01

    With diabetes rates escalating globally, there is the need for a better integration of all aspects of diabetes care for improved population outcomes. An understanding, not only of regional but global literature on physical activity barriers and its facilitators is important if healthcare providers and policy makers are to create programs tailored to their populations. Herein, we report the results of a narrative review of the global barriers and facilitators of physical activity for patients with diabetes mellitus. An in-depth literature search was conducted to identify English-language studies that examined physical activity barriers and associated facilitators among patients with diabetes mellitus. Major electronic literature databases that were searched included Google Scholar, PubMed, Hub-Med, and Highwire. Studies were available from Africa, Asia, Australia, Europe, and, predominantly North America. A total of 34 predominantly internal barriers emerged globally. The most commonly reported were time constrains, fear of provoking additional disorders, exercise venue and weather related barriers. Facilitators of physical activity were reported for most of the internal barriers (e.g. time constraints, lack of knowledge etc) while the external barriers (e.g. weather, environmental pollution etc) received only a minimal attention. Globally, patients with diabetes are confronted with an enormous number of physical activity barriers. Unlike the robust solutions proffered for the internal barriers, the literature is largely silent about solutions to the external barriers, which though fewer, may be highly influential. Additional data is needed to better understand physical activity behaviors in populations outside of North America.

  12. Barriers and motivators for physical activity among overweight and obese people with type 2 diabetes

    DEFF Research Database (Denmark)

    Lidegaard, Lærke; Schwennesen, Nete; Willaing, Ingrid

    2016-01-01

    Aim To explore barriers to and motivators for physical activity in a group of overweight and obese individuals with dysregulated Type 2 diabetes. Methods Data were collected from the Steno Diabetes Centre's outpatient clinic in Denmark. Four focus groups were conducted including 28 individuals...... with Type 2 diabetes aged 39–71 years. The facilitators used open-ended questions and probes such as images, statements and quotations about physical activity to foster active participation and interaction among participants. Focus groups were recorded on video and the discussions were transcribed...... and analysed thematically. Results We identified four main themes: 1) the body as a barrier to physical activity because of functional limitations; 2) logistical challenges, including lack of time and awareness of where to exercise in the local area; 3) being physically active with others, providing a sense...

  13. Minimum recommended physical activity, and perceived barriers and benefits of exercise in methadone maintained persons.

    Science.gov (United States)

    Caviness, Celeste M; Bird, Jessica L; Anderson, Bradley J; Abrantes, Ana M; Stein, Michael D

    2013-04-01

    Methadone-maintained persons are at increased risk for many physical and mental health disorders compared to the general population. Increased physical activity could offset these risks. We assessed physical activity level, and perceived benefits and barriers to exercise in a group of 305 methadone-maintained smokers. Mean participant age was 39.9 years, 50.2% were male, 79.7% were non-Hispanic White, and mean body mass index was 29.8. Nearly 45% endorsed fair or poor physical health. Although participants perceived many benefits of exercise and few barriers, only 38% of participants met weekly recommendations for physical activity, and nearly 25% reported no physical activity. Those who met recommended guidelines were significantly more likely to endorse relapse prevention as a benefit of exercise. Motivating MMT patients to increase physical activity could have important physical, mental health, and drug treatment benefits. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Barrier Island Activity to Illustrate Hands-On Science

    Science.gov (United States)

    Griffin, Suzanne H.

    revealed that although boys and girls are equally interested in certain areas of the subject, there are areas in Physics where boys and girls interests are significantly different. No differences were found in intensity of boys' and girls' interests towards suggested Physics topics at primary P6/P7 level, S3 and S5/S6 levels. At S2 and S4 levels a significant decline of girls' interests relative to boys interests was observed. S2 and S4 stages are decision making ones when pupils have the opportunity to select courses for the future. It was also revealed that the ratio of boys to girls in Physics once established at S2 level remains unchanged through the years of Standard Grade and Higher Grade Physics courses. This may indicate that if the number of girls in Physics is an issue for concern then attention should be paid to the primary and, especially early secondary years to attract girls to Physics. School Physics courses in Scotland revealed a high retention rate of girls in Physics. Analyses of preferred activities revealed that practical work is the most enjoyable activity in Science/Physics lessons for both girls and boys at every stage of schooling and studying the theory was found to be the least enjoyable activity at school for both genders at every age. The picture was almost the reverse with university Physics students.

  15. Promoting youth physical activity in rural southern communities: practitioner perceptions of environmental opportunities and barriers.

    Science.gov (United States)

    Edwards, Michael B; Theriault, Daniel S; Shores, Kindal A; Melton, Karen M

    2014-01-01

    Research on youth physical activity has focused on urban areas. Rural adolescents are more likely to be physically inactive than urban youth, contributing to higher risk of obesity and chronic diseases. Study objectives were to: (1) identify perceived opportunities and barriers to youth physical activity within a rural area and (2) identify rural community characteristics that facilitate or inhibit efforts to promote youth physical activity. Thirty in-depth interviews were conducted with expert informants in 2 rural southern US counties. Interviewees were recruited from diverse positions across multiple sectors based on their expert knowledge of community policies and programs for youth physical activity. Informants saw ball fields, natural amenities, and school sports as primary resources for youth physical activity, but they were divided on whether opportunities were abundant or scarce. Physical distance, social isolation, lack of community offerings, and transportation were identified as key barriers. Local social networks facilitated political action and volunteer recruitment to support programs. However, communities often lacked human capital to sustain initiatives. Racial divisions influenced perceptions of opportunities. Despite divisions, there were also examples of pooling resources to create and sustain physical activity opportunities. Developing partnerships and leveraging local resources may be essential to overcoming barriers for physical activity promotion in rural areas. Involvement of church leaders, school officials, health care workers, and cooperative extension is likely needed to establish and sustain youth rural physical activity programs. Allocating resources to existing community personnel and volunteers for continuing education may be valuable. © 2014 National Rural Health Association.

  16. Young adult males' motivators and perceived barrier towards eating healthily and being active: A qualitative study

    Science.gov (United States)

    There is a lack of understanding of young men's perspectives in obesity-related research. This study aims to: (1) identify young men's perceived motivators and barriers in adopting healthy eating and physical activity behaviors, and (2) explore any differences in responses by weight status categorie...

  17. Activism in Southeast Asian Ethnomusicology: Empowering Youths to Revitalize Traditions and Bridge Cultural Barriers

    Directory of Open Access Journals (Sweden)

    Sooi Beng Tan

    2008-12-01

    Full Text Available Beginning with a short overview of the strategies and activities in applied ethnomusicology in Southeast Asia, this paper focuses on the development of a socially engaged approach to empower young people in Malaysia to address two concerns: revitalizing traditions and bridging cultural barriers in a multiethnic and multireligious society where tensions often occur. 

  18. Adolescents' Perspectives on the Barriers and Facilitators of Physical Activity: A Systematic Review of Qualitative Studies

    Science.gov (United States)

    Martins, João; Marques, Adilson; Sarmento, Hugo; Carreiro da Costa, Francisco

    2015-01-01

    This article examined qualitative studies of adolescents' perspectives about the facilitators and barriers of physical activity, published from 2007 to 2014. A systematic review of "Web of Science", "EBSCO", "Psychinfo" and "ERIC" databases was performed according to Preferred Reporting Items for Systematic…

  19. Adolescents' Self-Efficacy to Overcome Barriers to Physical Activity Scale

    Science.gov (United States)

    Dwyer, John J. M.; Chulak, Tala; Maitland, Scott; Allison, Kenneth R.; Lysy, Daria C.; Faulkner, Guy E. J.; Sheeshka, Judy

    2012-01-01

    This paper describes a revised measure of self-efficacy to overcome barriers to moderate and vigorous physical activity in a sample of 484 high school students in Toronto, Ontario. The students had a mean age of 15.3 years. Principal axis factoring with oblique rotation yielded five factors: self-efficacy to overcome internal, harassment, physical…

  20. A Comparison of Motivational Factors and Barriers to Physical Activity among Traditional versus Nontraditional College Students

    Science.gov (United States)

    Kulavic, Kimberly; Hultquist, Cherilyn N.; McLester, John R.

    2013-01-01

    Objective: To investigate the motivational factors and the barriers to physical activity (PA) in traditional college students (TS) and nontraditional college students (NTS) and determine if differences exist between these 2 groups. Participants: A total of 746 college students; 628 were TS (19.1 [plus-minus] 1.2 years), and 118 were NTS (31.2…

  1. Confronting Physical Activity Programming Barriers for People with Disabilities: The Empowerment Model

    Science.gov (United States)

    Moran, Thomas Eugene; Taliaferro, Andrea R.; Pate, Joshua R.

    2014-01-01

    Community-based physical activity programs for people with disabilities have barriers that are unique to their program leader qualifications and the population they serve. Moran and Block (2010) argued that there is a need for practical strategies that are easy for communities to implement, maximize resources, and minimize the impact of barriers…

  2. Motivators, Facilitators, and Barriers to Physical Activity in Older Adults: A Qualitative Study.

    Science.gov (United States)

    Miller, Wendy; Brown, Patrick R

    In this descriptive, qualitative research study, the researchers used semistructured interviews with older adults who engaged in regular physical activity to identify common motivators, facilitators, and barriers to participating in regular exercise. The authors used these interviews to identify major themes and discuss implications for population health.

  3. Atomic Energy Research benchmark activity

    International Nuclear Information System (INIS)

    Makai, M.

    1998-01-01

    The test problems utilized in the validation and verification process of computer programs in Atomic Energie Research are collected into one bunch. This is the first step towards issuing a volume in which tests for VVER are collected, along with reference solutions and a number of solutions. The benchmarks do not include the ZR-6 experiments because they have been published along with a number of comparisons in the Final reports of TIC. The present collection focuses on operational and mathematical benchmarks which cover almost the entire range of reaktor calculation. (Author)

  4. Barriers to the diffusion of renewable energy technologies - A case study of the state of Maharashtra, India

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, B.S. [Indira Gandhi Inst. of Development Research, Mumbai (India)

    2001-07-01

    India's expanding economy and the strong growth expected in the next few decades (at around 10% per annum), will require additional energy. The use of fossil fuels is likely to dominate the strategy for meeting these needs in the near and medium term. However, India's own reserves are finite and will only be available for a limited period and the use of fossil fuels is not sustainable and is directly linked to environmental problems, particularly CO{sub 2} emissions and climate change. The importance of the increasing use of renewable energy sources was recognized in India in the early 1970s. During the past quarter century, a significant effort has gone into the development, trial and induction of a variety of technologies for use in different sectors. Today, India has one of the world's largest programs for renewable energy. The activities cower all the major renewable energy sources, including biogas, biomass, solar, wind and small-hydro power and other emerging technologies. By the end of 20th century nearly three million family-sized biogas plants (second in number in the world and next only to China's) and 30 million improved wood stoves have been established. These technologies could save about 15 million tons of fuel wood every year. Several other renewable energy technologies and products are now commercially available, and are economically viable in comparison to fossil fuels for some applications. However, there are many barriers to achieve the full potential of the renewable energy technologies. In order to study the potential and evaluate different RETs, we carried out a study of barriers to RETs in the state of Maharashtra, which accounts for about 16% of the Gross Domestic Product and 17% of the electricity supply in India. The study has been carried out in two parts. In the first part analysis was done on two technologies, viz., solar and wind. For doing this, information was collected from various secondary sources such as

  5. Reaction dynamics studies for the system 7Be + 208Pb at Coulomb barrier energies

    Directory of Open Access Journals (Sweden)

    Mazzocco M.

    2017-01-01

    Full Text Available The scattering process of the Radioactive Ion Beam 7Be from a 208Pb target was measured at three near-barrier energies. The quasi-elastic angular distributions were analyzed within the framework of the optical model to extract the reaction cross sections. The results are compared with those obtained for the reactions induced by the mirror projectile 7Li and by the lightest particle-stable lithium isotope 6Li on the same target. The angular distributions for the production of the two 7Be constituent clusters, namely 3He and 4He, were also measured. In agreement with what observed for the interaction of 7Be with lighter targets, the production of the heavier helium isotope resulted to be much more abundant than that of its lighter counterpart.

  6. Reaction dynamics studies for the system 7Be + 208Pb at Coulomb barrier energies

    Science.gov (United States)

    Mazzocco, M.; Boiano, A.; Boiano, C.; La Commara, M.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Strano, E.; Torresi, D.; Acosta, L.; Di Meo, P.; Fernandez-Garcia, J. P.; Glodariu, T.; Grebosz, J.; Guglielmetti, A.; Marquinez-Duran, G.; Martel, I.; Nicoletto, M.; Pakou, A.; Sánchez-Benítez, A. M.; Sava, T.; Sgouros, O.; Signorini, C.; Soramel, F.; Soukeras, V.; Stroe, L.

    2017-11-01

    The scattering process of the Radioactive Ion Beam 7Be from a 208Pb target was measured at three near-barrier energies. The quasi-elastic angular distributions were analyzed within the framework of the optical model to extract the reaction cross sections. The results are compared with those obtained for the reactions induced by the mirror projectile 7Li and by the lightest particle-stable lithium isotope 6Li on the same target. The angular distributions for the production of the two 7Be constituent clusters, namely 3He and 4He, were also measured. In agreement with what observed for the interaction of 7Be with lighter targets, the production of the heavier helium isotope resulted to be much more abundant than that of its lighter counterpart.

  7. Physical activity in patients with heart failure: barriers and motivations with special focus on sex differences

    Directory of Open Access Journals (Sweden)

    Klompstra L

    2015-11-01

    Full Text Available Leonie Klompstra,1 Tiny Jaarsma,1 Anna Strömberg2,31Department of Social and Welfare Studies, Faculty of Health Sciences, 2Department of Medical and Health Sciences, Division of Nursing, 3Department of Cardiology, Linköping University, Linköping, SwedenBackground: Adherence to recommendations for physical activity is low in both male and female patients with heart failure (HF. Men are more physically active than women. In order to successfully promote physical activity, it is therefore essential to explore how much and why HF patients are physically active and if this is related to sex. The aim of this study was therefore to evaluate physical activity in HF patients, to describe the factors related to physical activity, and to examine potential barriers and motivations to physical activity with special focus on sex differences.Methods: The study had a cross-sectional survey design. HF patients living at home received a questionnaire during May–July 2014, with questions on physical activity (from the Short Form-International Physical Activity Questionnaire, and potential barriers and motivations to physical activity.Results: A total of 154 HF patients, 27% women, with a mean age of 70±10 were included. In total, 23% of the patients reported a high level of physical activity, 46% a moderate level, and 34% a low level. Higher education, self-efficacy, and motivation were significantly associated with a higher amount of physical activity. Symptoms or severity of the disease were not related to physical activity. All the potential barriers to exercise were reported to be of importance. Psychological motivations were most frequently rated as being the most important motivation (41% to be physically active. Physical motivations (33% and social motivations were rated as the least important ones (22%. Women had significantly higher total motivation to be physically active. These differences were found in social, physical, and psychological

  8. Investment barriers and incentives for marine renewable energy in the UK: An analysis of investor preferences

    International Nuclear Information System (INIS)

    Leete, Simeon; Xu, Jingjing; Wheeler, David

    2013-01-01

    Deployment of marine renewable energy (MRE) in the UK is desirable in order to address climate change, meet mandatory EU renewable energy targets and provide significant economic development opportunities, including new export markets. Public funding constraints in the UK mean that substantial investment is required from the private sector to commercialize the industry. By focussing on investor attitudes and behaviours towards wave and tidal technologies, this paper reveals significant observations from the investment community with serious implications for the future of the MRE industry. Through a series of in-depth interviews with individuals from the investment community, device developers and industry support, the research seeks to identify common barriers and incentives to investment. The paper demonstrates that although investors' attitudes are generally aligned, they do appear to have changed over time. Of the participants that had previously invested in early stage MRE device development, none were likely to do so again. It is concluded that this is a function of investors' greater understanding of the scale, and unpredictability of the costs, and the length of time required to develop these technologies. This presents a significant policy challenge for all actors interested in the commercialization of wave and tidal technologies. - Highlights: • Performed a series of in-depth interviews with senior finance and industry actors. • Examined investor attitudes and policy preferences that may encourage investment. • VC investors are currently disinclined to invest in early stage device development. • Policy instability, level of capital and revenue support are key investment barriers. • Commercialization requires strategic government and industrial partner investment

  9. Pulse-height response of silicon surface-barrier detectors to high-energy heavy ions

    International Nuclear Information System (INIS)

    Smith, G.D.

    1973-01-01

    The pulse-height defect (PHD) of high-energy heavy ions in silicon surface-barrier detectors can be divided into three components: (1) energy loss in the gold-surface layer, (2) a nuclear-stopping defect, and (3) a defect due to recombination of electron-hole pairs in the plasma created by the heavy ion. The plasma recombination portion of the PHD was the subject of this study using the variation of the PHD with (1) the angle of incidence of incoming heavy ions, and (2) changes in the detector bias. The Tandem Van de Graaff accelerator at Argonne National Laboratory was used to produce scattered beam ions ( 32 S, 35 Cl) and heavy target recoils (Ni, Cu, 98 Mo, Ag, Au) at sufficient energies to produce a significant recombination defect. The results confirm the existence of a recombination zone at the front surface of these detectors and the significance of plasma recombination as a portion of the pulse-height defect. (Diss. Abstr. Int., B)

  10. Investigation of {sup 17}F+p elastic scattering at near-barrier energies

    Energy Technology Data Exchange (ETDEWEB)

    El-Azab Farid, M. [Assiut University, Physics Department, Assiut (Egypt); Ibraheem, Awad A. [Al-Azhar University, Physics Department, Assiut (Egypt); King Khalid University, Physics Department, Abha (Saudi Arabia); Al-Hajjaji, Arwa S. [Taiz University, Physics Department, Taiz (Yemen)

    2015-10-15

    The {sup 17}F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus {sup 17}F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)

  11. Investigation of 17F+p elastic scattering at near-barrier energies

    International Nuclear Information System (INIS)

    El-Azab Farid, M.; Ibraheem, Awad A.; Al-Hajjaji, Arwa S.

    2015-01-01

    The 17 F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus 17 F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)

  12. Perceived barriers by university students in the practice of physical activities.

    Science.gov (United States)

    Gómez-López, Manuel; Gallegos, Antonio Granero; Extremera, Antonio Baena

    2010-01-01

    The main goal of this research is to study in detail the main characteristics of university students in order to find out the reasons why they have adopted an inactive lifestyle. In order to do so, a questionnaire on the analysis of sports habits and lifestyle was given to 323 students. They were taken from a representative sample of 1834 students. These 323 students had pointed out at the moment of the fieldwork, not having practiced any sport in their spare time. Our findings point out that there are diverse reasons for this. On one hand, reasons referred to as external barriers such as lack of time, on the other hand, internal barriers such as not liking the physical activity, not seeing its practicality or usefulness, feeling lazy or with apathy, or thinking that they are not competent in this type of activities. Other reasons such as the lack of social support are grouped within the external barriers. Finally, it is important to stress that there are also differences based on gender with respect to motivation. Key pointsExternal barriers prevail in university students. The lack of time is among the most highlighted ones.Statistically significant results have been found regarding the gender variable.The results are very important since they are considered to be valuable information for university institutions when guiding and diversifying their offer of physical and sport activities. Also as a guide in the design of support policies and national sport management guidelines.

  13. Levels of physical activity, motivation and barriers to participation in university students.

    Science.gov (United States)

    Sevil, Javier; Práxedes, Alba; Abarca-Sos, Alberto; Del Villar, Fernando; García-González, Luis

    2016-10-01

    Grounded in self-determination theory and trans-theoretical model applied to exercise, the aim of this study was to analyse the existing relationships between physical activity (PA) carried out by university students, perceived barriers to PA, motivation to PA and stages of change. 901 Spanish students took part in the study (408 men, 493 women; mean age 22.59±3.59), who completed the Behavioural Regulation in Exercise Questionnaire (BREQ-3), Scale of Barriers to PA, Stages of Change and the International Physical Activity Questionnaire - Short Form (IPAQ-SF). Noteworthy among the findings is the positive relationship between the more autonomous regulation forms, especially integrated regulation, and the moderate to vigorous PA (MVPA) levels. However, barriers to participatrion are negatively related to PA levels and the more self-determined forms of motivation. Finally, students in action and maintenance stages, and those who comply with the recommendations on PA present higher values in the more self-determined motivation forms and lower values in barriers to participation in PA. The study shows the importance of addressing the analysis of variables associated with engagement in PA in the university population to develop healthy policies and intervention programmes that can establish a series of healthy and more active habits in the youth-adult stage. The appropriateness of promoting more self-determined motivation forms is highlighted, especially integrated regulation, to have an impact on higher levels of MVPA.

  14. Physical activity preferences, motivators, barriers and attitudes of adults with mental illness.

    Science.gov (United States)

    Chapman, Justin J; Fraser, Sarah J; Brown, Wendy J; Burton, Nicola W

    2016-10-01

    Adults with mental illness may have specific attitudes toward physical activity (PA). To assess the PA attitudes of non-institutionalised adults with mental illness, and associations with psychological distress. Participants completed questionnaires on activity preferences (type, context and sources of support), motivators, barriers and attitudes toward personal training (PT). Relationships between responses and distress were assessed using logistic regressions. One-hundred forty-two participants completed the questionnaires. PA context preferences included activities done close to home, outdoors, with professional instruction, with people of the same ability, as part of a healthy lifestyle program and with a social component. The most commonly endorsed source of support was an exercise instructor. Most respondents had never received PT; however, PT had high acceptability. Common barriers included poor physical and mental health, and lack of money. Distress was positively associated with barriers of poor mental health, tiredness, disorganisation, exhaustion and being shy/embarrassed (p ≤ 0.001). Local outdoor walking groups that include social and healthy lifestyle components, and that are led by an exercise instructor who can provide support for overcoming barriers, may best meet PA interests of this group. PT could be an acceptable method for offering individualised support.

  15. Barriers and enablers to physical activity participation in patients with COPD: a systematic review.

    Science.gov (United States)

    Thorpe, Olivia; Johnston, Kylie; Kumar, Saravana

    2012-01-01

    Physical activity (PA) has been shown to improve symptoms in people with chronic obstructive pulmonary disease (COPD). Despite the high health and financial costs, the uptake of management strategies, particularly participation in PA and pulmonary rehabilitation (PR), are low. The review objective here was to identify potential barriers and enablers, which people with COPD report being associated with their participation in PA programs, including PR. A systematic search was undertaken to identify studies (published Jan 2000 to Aug 2011) reporting any barriers and enablers experienced by people with COPD regarding participation in PA and PR. Methodological quality of the studies was appraised using McMaster critical appraisal tools. A narrative summary of findings was undertaken reporting on individual study characteristics, country of origin, participants, and potential barriers and enablers. Eleven studies (8 qualitative and 3 quantitative) met the inclusion criteria for this systematic review. Several methodological issues (small sampling, poor description of data collection and analysis, issues with generalizability of the research findings) were common among included studies. Barriers identified included changing health status, personal issues, lack of support, external factors, ongoing smoking, and program-specific barriers. Enablers identified included social support, professional support, personal drivers, personal benefit, control of condition, specific goals, and program-specific enablers. The findings from this review may assist health professionals, patients, care givers and the wider community to develop effective strategies to promote participation in PA and PR among people with COPD.

  16. Biological and Sociocultural Differences in Perceived Barriers to Physical Activity among 5th–7th Grade Urban Girls

    Science.gov (United States)

    Vermeesch, Amber L.; Ling, Jiying; Voskuil, Vicki R.; Bakhoya, Marion; Wesolek, Stacey M.; Bourne, Kelly A.; Pfeiffer, Karin A.; Robbins, Lorraine B.

    2015-01-01

    Background Inadequate physical activity (PA) contributes to the high prevalence of overweight and obesity among U.S. adolescent girls. Barriers preventing adolescent girls from meeting PA guidelines have not been thoroughly examined. Objectives The threefold purpose of this study was to: (a) determine pubertal stage, racial/ethnic, and socioeconomic status (SES) differences in ratings of interference of barriers to PA; (b) examine relationships between perceived barriers and age, body mass index (BMI), recreational screen time, sedentary activity, and PA; and (c) identify girls’ top-rated perceived barriers to PA. Methods Girls (N = 509) from eight Midwestern U.S. schools participated. Demographic, pubertal stage, perceived barriers, and recreational screen time data were collected via surveys. Height and weight were measured. Accelerometers measured sedentary activity, moderate-to-vigorous physical activity (MVPA), and light plus MVPA. Results Girls of low SES reported greater interference of perceived barriers to PA than those who were not of low SES (1.16 vs. 0.97, p = .01). Girls in early/middle puberty had lower perceived barriers than those in late puberty (1.03 vs. 1.24, p barriers were negatively related to MVPA (r = −.10, p = .03) and light plus MVPA (r = −.11, p = .02). Girls’ top five perceived barriers included lack of skills, hating to sweat, difficulty finding programs, being tired, and having pain. Discussion Innovative interventions, particularly focusing on skill development, are needed to assist girls in overcoming their perceived barriers to PA. PMID:26325276

  17. Computing the Free Energy Barriers for Less by Sampling with a Coarse Reference Potential while Retaining Accuracy of the Target Fine Model.

    Science.gov (United States)

    Plotnikov, Nikolay V

    2014-08-12

    Proposed in this contribution is a protocol for calculating fine-physics (e.g., ab initio QM/MM) free-energy surfaces at a high level of accuracy locally (e.g., only at reactants and at the transition state for computing the activation barrier) from targeted fine-physics sampling and extensive exploratory coarse-physics sampling. The full free-energy surface is still computed but at a lower level of accuracy from coarse-physics sampling. The method is analytically derived in terms of the umbrella sampling and the free-energy perturbation methods which are combined with the thermodynamic cycle and the targeted sampling strategy of the paradynamics approach. The algorithm starts by computing low-accuracy fine-physics free-energy surfaces from the coarse-physics sampling in order to identify the reaction path and to select regions for targeted sampling. Thus, the algorithm does not rely on the coarse-physics minimum free-energy reaction path. Next, segments of high-accuracy free-energy surface are computed locally at selected regions from the targeted fine-physics sampling and are positioned relative to the coarse-physics free-energy shifts. The positioning is done by averaging the free-energy perturbations computed with multistep linear response approximation method. This method is analytically shown to provide results of the thermodynamic integration and the free-energy interpolation methods, while being extremely simple in implementation. Incorporating the metadynamics sampling to the algorithm is also briefly outlined. The application is demonstrated by calculating the B3LYP//6-31G*/MM free-energy barrier for an enzymatic reaction using a semiempirical PM6/MM reference potential. These modifications allow computing the activation free energies at a significantly reduced computational cost but at the same level of accuracy compared to computing full potential of mean force.

  18. Motivation and Barriers for Leisure-Time Physical Activity in Socioeconomically Disadvantaged Women.

    Science.gov (United States)

    Santos, Inês; Ball, Kylie; Crawford, David; Teixeira, Pedro J

    2016-01-01

    The aim of this study was to examine cross-sectional and longitudinal associations between motivation and barriers for physical activity, and physical activity behavior in women living in socioeconomic disadvantage. This study also examined whether weight control intentions moderate those associations. Data from 1664 women aged 18-46 years was collected at baseline and three-year follow-up as part of the Resilience for Eating and Activity Despite Inequality study. In mail-based surveys, women reported sociodemographic and neighborhood environmental characteristics, intrinsic motivation, goals and perceived family barriers to be active, weight control intentions and leisure-time physical activity (assessed through the IPAQ-L). Linear regression models assessed the association of intrinsic motivation, goals and barriers with physical activity at baseline and follow-up, adjusting for environmental characteristics and also physical activity at baseline (for longitudinal analyses), and the moderating effects of weight control intentions were examined. Intrinsic motivation and, to a lesser extent, appearance and relaxation goals for being physically active were consistently associated with leisure-time physical activity at baseline and follow-up. Perceived family barriers, health, fitness, weight and stress relief goals were associated with leisure-time physical activity only at baseline. Moderated regression analyses revealed that weight control intentions significantly moderated the association between weight goals and leisure-time physical activity at baseline (β = 0.538, 99% CI = 0.057, 0.990) and between intrinsic motivation and leisure-time physical activity at follow-up (β = 0.666, 99% CI = 0.188, 1.145). For women actively trying to control their weight, intrinsic motivation was significantly associated with leisure-time physical activity at follow-up (β = 0.184, 99% CI = 0.097, 0.313). Results suggest that, especially in women trying to control their weight

  19. Motivators of and Barriers to Engaging in Physical Activity: Perspectives of Low-Income Culturally Diverse Adolescents and Adults

    Science.gov (United States)

    Bragg, Marie A.; Tucker, Carolyn M.; Kaye, Lily B.; Desmond, Frederic

    2009-01-01

    Background: Obesity rates are rising in the United States, especially among low-income and racial/ethnic minority individuals. Exploring motivators and barriers relative to engaging in physical activity is imperative. Purpose: The purpose of this study was to identify motivators and barriers relative to engagement in physical activity as reported…

  20. Energy SMEs in sub-Saharan Africa: Outcomes, barriers and prospects in Ghana, Senegal, Tanzania and Zambia

    DEFF Research Database (Denmark)

    Haselip, James Arthur; Desgain, Denis DR; Mackenzie, Gordon A.

    a commercially viable energy SME sector, emphasising the lack of strong policy support from governments, poor business skills capacity and the high cost of many RETs as related cause-and-effect barriers. While these issues continue to characterise, to a greater or lesser extent, the energy SMEs sectors......; lack of clearly defined markets; demand-side barriers to purchase relatively high capital-intense energy products. Where numerous energy SMEs are in operation and thus where a valid demonstration effect can be identified, there is a perceived paradox that serves to undermine commercial interest...... in investing in energy SMEs. The paradox is that the donor-supported businesses that were issued with concessional and/or flexible loans serve to demonstrate that these businesses depend upon such concessional terms, i.e., that they could not survive in ‘the real world’. While this assumption is widely...

  1. Active barrier films of PET for solar cell application: Processing and characterization

    International Nuclear Information System (INIS)

    Rossi, Gabriella; Scarfato, Paola; Incarnato, Loredana

    2014-01-01

    A preliminary investigation was carried out on the possibility to improve the protective action offered by the standard multilayer structures used to encapsulate photovoltaic devices. With this aim, a commercial active barrier PET-based material, able to absorb oxygen when activated by liquid water, was used to produce flexible and transparent active barrier films, by means of a lab-scale film production plant. The obtained film, tested in terms of thermal, optical and oxygen absorption properties, shows a slow oxygen absorption kinetics, an acceptable transparency and an easy roll-to-roll processability, so proving itself as a good candidate for the development of protective coating for solar cells against the atmospheric degradation agents like the rain

  2. Biological and Sociocultural Differences in Perceived Barriers to Physical Activity Among Fifth- to Seventh-Grade Urban Girls.

    Science.gov (United States)

    Vermeesch, Amber L; Ling, Jiying; Voskuil, Vicki R; Bakhoya, Marion; Wesolek, Stacey M; Bourne, Kelly A; Pfeiffer, Karin A; Robbins, Lorraine B

    2015-01-01

    Inadequate physical activity (PA) contributes to the high prevalence of overweight and obesity among U.S. adolescent girls. Barriers preventing adolescent girls from meeting PA guidelines have not been thoroughly examined. The threefold purpose of this study was to (a) determine pubertal stage, racial/ethnic, and socioeconomic status (SES) differences in ratings of interference of barriers to PA; (b) examine relationships between perceived barriers and age, body mass index, recreational screen time, sedentary activity, and PA; and (c) identify girls' top-rated perceived barriers to PA. Girls (N = 509) from eight Midwestern U.S. schools participated. Demographic, pubertal stage, perceived barriers, and recreational screen time data were collected via surveys. Height and weight were measured. Accelerometers measured sedentary activity, moderate-to-vigorous PA (MVPA), and light plus MVPA. Girls of low SES reported greater interference of perceived barriers to PA than those who were not of low SES (1.16 vs. 0.97, p = .01). Girls in early/middle puberty had lower perceived barriers than those in late puberty (1.03 vs. 1.24, p barriers were negatively related to MVPA (r = -.10, p = .03) and light plus MVPA (r = -.11, p = .02). Girls' top five perceived barriers included lack of skills, hating to sweat, difficulty finding programs, being tired, and having pain. Innovative interventions, particularly focusing on skill development, are needed to assist girls in overcoming their perceived barriers to PA.

  3. Perceived barriers and facilitators to participation in physical activity for children with disability: a qualitative study.

    Science.gov (United States)

    Shields, Nora; Synnot, Anneliese

    2016-01-19

    Children with disability engage in less physical activity compared to their typically developing peers. Our aim was to explore the barriers and facilitators to participation in physical activity for this group. Ten focus groups, involving 63 participants (23 children with disability, 20 parents of children with disability and 20 sport and recreation staff), were held to explore factors perceived as barriers and facilitators to participation in physical activity by children with disability. Data were analysed thematically by two researchers. Four themes were identified: (1) similarities and differences, (2) people make the difference, (3) one size does not fit all, and (4) communication and connections. Key facilitators identified were the need for inclusive pathways that encourage ongoing participation as children grow or as their skills develop, and for better partnerships between key stakeholders from the disability, sport, education and government sectors. Children with disabilities' need for the early attainment of motor and social skills and the integral role of their families in supporting them were considered to influence their participation in physical activity. Children with disability were thought to face additional barriers to participation compared to children with typical development including a lack of instructor skills and unwillingness to be inclusive, negative societal attitudes towards disability, and a lack of local opportunities. The perspectives gathered in this study are relevant to the many stakeholders involved in the design and implementation of effective interventions, strategies and policies to promote participation in physical activity for children with disability. We outline ten strategies for facilitating participation.

  4. BARRIERS TO ENERGY ACCESS IN THE URBAN POOR AREAS OF DHAKA, BANGLADESH: ANALYSIS OF PRESENT SITUATION AND RECOMMENDATIONS

    Directory of Open Access Journals (Sweden)

    Molla Shahadat Hossain Lipu

    2013-10-01

    Full Text Available Energy is a crucial input to promote socioeconomic development. In Bangladesh, about 96 million people (59% do not have access to electricity and 143 million people (88% still depend on biomass for cooking. The urban poor living in slum areas with lack of access to clean and modern sources of energy have not been addressed comprehensively. The main objective of this study is to identify the barriers faced by the urban poor in the slum areas of Dhaka in accessing different fuels and provide specific recommendations to overcome the barriers to enable energy access. The study is mainly based on field survey covering 185 households of the four major slum areas of Dhaka, literature review, and stakeholder interviews. Many barriers have been identified through this research where urban poor face problems in accessing legal energy services due to illegal settlement, lack of explicit policy on energy and housing, lack of dedicated institution, the pervasive role of Mastaans, poor infrastructure and lack of monitoring and evaluating system. Barriers specific recommendations are also suggested based on the experiences from the field visit and the best practices outside Bangladesh are also identified.

  5. Financing renewable energy in developing countries. Drivers and barriers for private finance in sub-Saharan Africa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-02-15

    The focus of this report is to identify and portray current barriers to the scaling up of private investment and finance for electricity generation from renewable energy sources in the sub-Saharan region. Best practice in tackling these barriers is identified, partly from a literature review but especially from the results of a survey conducted among 36 financial institutions that are UNEP Finance Initiative members and two non-member banks (all survey respondents have experience in the field of energy infrastructure finance). Promising avenues in the areas of local policy reform, incentive mechanisms and international de-risking instruments are highlighted. In particular, this report addresses the following questions: (a) Why are sub-Saharan Africa and developing countries elsewhere failing to expand electricity generation from renewable sources? What are the barriers to such expansion? What is keeping the risk-return profile of renewable energy investments in sub-Saharan Africa unattractive and projects commercially unviable?; (b) What have been the experiences of private sector lenders and investors in the area of renewable energy projects in developing countries? What barriers and drivers have they encountered, and how can these experiences be of use in sub-Saharan Africa?; (c) What can be learned from the modest but encouraging successes of a few sub-Saharan African countries? Can these results be replicated? What was done in these countries to improve the risk-return profile of renewable energy and unlock private finance?.

  6. Self-reported physical activity in patients on chronic hemodialysis: correlates and barriers.

    Science.gov (United States)

    Bossola, Maurizio; Pellu, Valentina; Di Stasio, Enrico; Tazza, Luigi; Giungi, Stefania; Nebiolo, Pier Eugenio

    2014-01-01

    The knowledge of the barriers that are associated with decreased physical activity (PA) in patients on chronic hemodialysis (PCH) may be of primary importance for the nephrologists. Thus, we aimed to assess the barriers associated with the absent or reduced PA in PCH of a Mediterranean country. Patients were invited to answer the question 'How often do you exercise during your leisure time?'. Also, patients included in the study were asked to answer questions regarding barriers to physical activity lower than desired. We studied 105 patients. Forty (38.1%) patients reported to never exercise, 6 (5.7%) reported to exercise less than once/week, 4 (3.8%) once/week, 23 (21.9%) two to three times/week, 12 (11.4%) four to five times/week and 20 (19%) daily. Overall, 46 (43.8%) patients never exercised or exercised less than once/week ('inactive') and 59 (56.2%) did exercise more often ('active'). At the multivariate analysis, reduced walking ability, fatigue on the non-dialysis days, and shortness of breath were independently and negatively associated with PA. The same results were found when the reduced model of the multivariate logistic backward regression was built introducing in the model also clinical and laboratory variables. In PCH, fatigue on the non-dialysis days, reduced walking ability, and shortness of breath are barriers independently associated to decreased PA. Knowledge about the causes and mechanisms that generate these barriers has to be acquired. © 2014 S. Karger AG, Basel.

  7. Barriers to physical activity and restorative care for residents in long-term care: a review of the literature.

    Science.gov (United States)

    Benjamin, Kathleen; Edwards, Nancy; Ploeg, Jenny; Legault, Frances

    2014-01-01

    Despite the benefits of physical activity, residents living in long-term care (LTC) are relatively sedentary. Designing successful physical activity and restorative care programs requires a good understanding of implementation barriers. A database search (2002-2013) yielded seven studies (nine articles) that met our inclusion criteria. We also reviewed 31 randomized controlled trials (RCTs) to determine if the authors explicitly discussed the barriers encountered while implementing their interventions. Eleven RCTs (13 articles) included a discussion of the barriers. Hence, a total of 18 studies (22 articles) were included in this review. Barriers occurred at resident (e.g., health status), environmental (e.g., lack of space for physical activity), and organizational (e.g., staffing and funding constraints) levels. These barriers intersect to adversely affect the physical activity of older people living in LTC. Future studies targeting physical activity interventions for residents living in LTC are needed to address these multiple levels of influence.

  8. Historical changes in the Mississippi-Alabama barrier islands and the roles of extreme storms, sea level, and human activities

    Science.gov (United States)

    Morton, Robert A.

    2007-01-01

    An historical analysis of images and documents shows that the Mississippi-Alabama (MS-AL) barrier islands are undergoing rapid land loss and translocation. The barrier island chain formed and grew at a time when there was a surplus of sand in the alongshore sediment transport system, a condition that no longer prevails. The islands, except Cat, display alternating wide and marrow segments. Wide segments generally were products of low rates of inlet migration and spit elongation that resulted in well-defined ridges and swales formed by wave refraction along the inlet margins. In contrast, rapid rates of inlet migration and spit elongation under conditions of surplus sand produced low, narrow, straight barrier segments. Since the mid 1800s, average rates of land loss for all the MS islands accelerated systematically while maintaining consistency from island to island. In contrast, Dauphin Island, off the Alabama coast, gained land during the early 20th century and then began to lose land at rates comparable to those of the MS barriers. There is an inverse relationship between island size and percentage of land reduction for each barrier such that Horn Island lost 24% and Ship Island lost 64% of its area since the mid 1800s. Ship Island is particularly vulnerable to storm-driven land losses because topographic and bathymetric boundary conditions focus wave energy onto the island. The three predominant morphodynamic processes associated with land loss are: (1) unequal lateral transfer of sand related to greater updrift erosion compared to downdrift deposition, (2) barrier narrowing resulting from simultaneous erosion of the Gulf and Soundside shores, and (3) barrier segmentation related to storm breaching. The western three fourths of Dauphin Island are migrating landward as a result of storms that erode the Gulf shore, overwash the island, and deposit sand in Mississippi Sound. Petit Bois, Horn, and Ship Islands have migrated westward as a result of predominant

  9. Impact of compliance with different guidelines on physical activity during pregnancy and perceived barriers to leisure physical activity.

    Science.gov (United States)

    Santos, Paula Clara; Abreu, Sandra; Moreira, Carla; Lopes, Diana; Santos, Rute; Alves, Odete; Silva, Pedro; Montenegro, Nuno; Mota, Jorge

    2014-01-01

    The aims of the this prospective study were to analyse physical activity (PA) engagement during the first and second trimesters, considering the different guidelines published on PA, to document the individual characteristics associated with the accomplishment of these guidelines and to examine pregnant women's perceived barriers to leisure PA, using a socioecological framework. A sample of 133 pregnant women in two stages--at 10-12 weeks' gestation (T1) and 20-22 weeks' gestation (T2)--were evaluated. PA was assessed by accelerometry during the T1 and T2 evaluation stages. Socio-demographic characteristics, lifestyle factors and barriers to leisure PA were assessed via questionnaire. A large proportion of women (ranging from 32% to 96%) did not reach the levels of PA recommended by the guidelines. There were no significant differences between T1 and T2 with regard to compliance with PA recommendations. A decrease in PA levels from T1 to T2 was noted for all recommendations. No associations were found between participants' characteristics and adherence to the recommendations in T1 and T2. No significant differences were found in barriers to leisure PA between T1 and T2. The most commonly reported barriers to leisure PA were intrapersonal, not health related. Our results indicate that there were no differences between trimesters regarding compliance of PA recommendations, and perceived barriers were similar in both trimesters.

  10. Barriers to Physical Activity in Children With Autism Spectrum Disorders: Relationship to Physical Activity and Screen Time.

    Science.gov (United States)

    Must, Aviva; Phillips, Sarah; Curtin, Carol; Bandini, Linda G

    2015-04-01

    Individual, social, and community barriers to physical activity (PA) experienced by children with autism spectrum disorder (ASD) make PA participation more difficult and may contribute to increased screen time. We compared the prevalence of parent-reported barriers to PA among 58 typically developing (TD) children and 53 children with an ASD, 3 to 11 years, and assessed the association between barriers and PA participation and screen time among children with ASD. Parents of children with ASD reported significantly more barriers than parents of TD children. Based on parent-report, 60% of children with ASD required too much supervision compared with no TD children (P barriers to PA was inversely correlated with the hours spent in PA per year (r = -0.27, P = .05) and positively related to total screen time (r = .32, P < .03). These findings underscore the need for community-based PA programs designed to meet the special requirements of this population and policies that compel schools and other government-supported organizations for inclusion and/or targeted programming.

  11. Perceived Barriers to Healthy Eating and Physical Activity among Adolescents in Seven Arab Countries: A Cross-Cultural Study

    Directory of Open Access Journals (Sweden)

    Abdulrahman O. Musaiger

    2013-01-01

    Full Text Available Objective. To highlight the perceived personal, social, and environmental barriers to healthy eating and physical activity among Arab adolescents. Method. A multistage stratified sampling method was used to select 4698 students aged 15–18 years (2240 males and 2458 females from public schools. Seven Arab counties were included in the study, namely, Algeria, Jordan, Kuwait, Libya, Palestine, Syria, and the United Arab Emirates. Self-reported questionnaire was used to list the barriers to healthy eating and physical activity facing these adolescents. Results. It was found that lack of information on healthy eating, lack of motivation to eat a healthy diet, and not having time to prepare or eat healthy food were the main barriers to healthy eating among both genders. For physical activity, the main barriers selected were lack of motivation to do physical activity, less support from teachers, and lack of time to do physical activity. In general, females faced more barriers to physical activity than males in all countries included. There were significant differences between males and females within each country and among countries for most barriers. Conclusion. Intervention programmes to combat obesity and other chronic noncommunicable diseases in the Arab world should include solutions to overcome the barriers to weight maintenance, particularly the sociocultural barriers to practising physical activity.

  12. Risk assessment in a foundry unit by energy trace and barrier analysis method (ETBA

    Directory of Open Access Journals (Sweden)

    S.A. Ayati

    2010-01-01

    Full Text Available Background and aimsAs a Development of Industrial process, human, environment,equipment, material and validity of system has been exposed to hazardous conditions. Regards of32.3 percent of occupations in industries, this study focused on risk assessment of foundry unit byenergy trace and barrier analysis (ETBA method and presented approaches to control of accident.Methodsthe recent study is as a case study one to risk assessment in a foundry unit in Qazvinindustrial city in1387. In this study risks were founded by ETBA method and evaluated by MILSTD-882B. Data were collected by direct observations, interview with workers and supervisorand engineers, walking-talking through method, documents investigation of operationalprocessors, preventive maintenances, equipment technical properties, accidental and medicaldocuments. Finally ETBA worksheets completed.Findingstotally 154 risks has been found. 40 from total are been unacceptable risk, 68unfavorable and also 46 acceptable but with remediation action. Casting workshop had risks morethan other workshops (with 74 identified risks.Potential and heat energies were founded as mosthazardous energies, with respectively 51 and 38 risk cases.ConclusionThis study recommended to be done actions for identification and control risk,such as: safety training, occupation training, preventive maintenance, contract safety, safetycommunication and safety audit group.

  13. Role of codeposited impurities during growth. II. Dependence of morphology on binding and barrier energies

    Science.gov (United States)

    Sathiyanarayanan, Rajesh; Hamouda, Ajmi Bh.; Pimpinelli, A.; Einstein, T. L.

    2011-01-01

    In an accompanying article we showed that surface morphologies obtained through codeposition of a small quantity (2%) of impurities with Cu during growth (step-flow mode, θ = 40 ML) significantly depends on the lateral nearest-neighbor binding energy (ENN) to Cu adatom and the diffusion barrier (Ed) of the impurity atom on Cu(0 0 1). Based on these two energy parameters, ENN and Ed, we classify impurity atoms into four sets. We study island nucleation and growth in the presence of codeposited impurities from different sets in the submonolayer (θ⩽ 0.7 ML) regime. Similar to growth in the step-flow mode, we find different nucleation and growth behavior for impurities from different sets. We characterize these differences through variations of the number of islands (Ni) and the average island size with coverage (θ). Further, we compute the critical nucleus size (i) for all of these cases from the distribution of capture-zone areas using the generalized Wigner distribution.

  14. Dynamics of 28,30S i* compound nuclei formed at sub-barrier energies

    Science.gov (United States)

    Kaur, Manpreet; Singh, Bir Bikram; Kaur, Sarbjeet

    2018-05-01

    The decay of 28S i* and 30S i* compound nuclei (CN) formed at sub-barrier energies, in the reactions induced by stable projectile 16O and exotic projectile 18O, respectively, has been investigated within the quantum mechanical fragmentation theory based dynamical cluster-decay model (DCM). The collective potential energy surface shows that xα-type (x is an integer) clusters are minimized in the decay of 28S i* while in case of 30S i* in addition to xα-type clusters, np-xα (n, p are neutron and proton, respectively) type clusters are also minimized. These minimized fragments have more preformation probability P0, which is an important factor through which nuclear structure effects of decaying CN are probed, within DCM. The results show that light particles (LPs) are contributing mostly in the fusion cross-section, σfusion. In case of 30S i*, the contribution of 1n is highest and more compared to 4He in case of 28S i*, which seems to play an important role in fusion enhancement. The DCM calculated σfusion for both the CN formed with same Ec.m. = 7.0 MeV gives more value for σfusion of 30S i*, in agreement with the experimental data.

  15. Assessment of active play, inactivity and perceived barriers in an inner city neighborhood

    Science.gov (United States)

    Kottyan, Gregg; Kottyan, Leah; Edwards, Nicholas M.; Unaka, Ndidi I.

    2014-01-01

    Avondale, a disadvantaged neighborhood in Cincinnati, lags behind on a number of indicators of child well-being. Childhood obesity has become increasingly prevalent, as one third of Avondale’s kindergarteners are obese or overweight. The study objective was to determine perceptions of the quantity of and obstacles to childhood physical activity in the Avondale community. Caregivers of children from two elementary schools were surveyed to assess their child’s physical activity and barriers to being active. Three hundred forty surveys were returned out of 1,047 for a response rate of 32%. On school days, 41% of caregivers reported that their children spent more than 2 hours watching television, playing video games, or spending time on the computer. While over half of respondents reported that their children get more than 2 hours of physical activity on school days, 14% of children were reported to be physically active less than 1 hour per day. Caregivers identified violence, cost of extracurricular activities, and lack of organized activities as barriers to their child’s physical activity. The overwhelming majority of caregivers expressed interest in a program to make local playgrounds safer. In conclusion, children in Avondale are not participating in enough physical activity and are exposed to more screen time than is recommended by the AAP. Safety concerns were identified as a critical barrier to address in future advocacy efforts in this community. This project represents an important step toward increasing the physical activity of children in Avondale and engaging the local community. PMID:24306236

  16. Prediction of point-defect migration energy barriers in alloys using artificial intelligence for atomistic kinetic Monte Carlo applications

    Energy Technology Data Exchange (ETDEWEB)

    Castin, N. [Structural Materials Group, Nuclear Materials Science Institute, Studiecentrum voor Kerneenergie Centre d' etude de l' energie nucleaire (SCK CEN), Boeretang 200, B-2400 Mol (Belgium); Universite Libre de Bruxelles (ULB), Physique des Solides Irradies et Nanostructures (PSIN), CP234 Boulevard du triomphe, Brussels (Belgium); Malerba, L. [Structural Materials Group, Nuclear Materials Science Institute, Studiecentrum voor Kerneenergie Centre d' etude de l' energie nucleaire (SCK CEN), Boeretang 200, B-2400 Mol (Belgium)], E-mail: lmalerba@sckcen.be

    2009-09-15

    We significantly improved a previously proposed method to take into account chemical and also relaxation effects on point-defect migration energy barriers, as predicted by an interatomic potential, in a rigid lattice atomistic kinetic Monte Carlo simulation. Examples of energy barriers are rigorously calculated, including chemical and relaxation effects, as functions of the local atomic configuration, using a nudged elastic bands technique. These examples are then used to train an artificial neural network that provides the barriers on-demand during the simulation for each configuration encountered by the migrating defect. Thanks to a newly developed training method, the configuration can include a large number of neighbour shells, thereby properly including also strain effects. Satisfactory results have been obtained when the configuration includes different chemical species only. The problems encountered in the extension of the method to configurations including any number of point-defects are stated and solutions to tackle them are sketched.

  17. An understanding of Japanese children's perceptions of fun, barriers, and facilitators of active free play.

    Science.gov (United States)

    Lee, YingHua; Takenaka, Koji; Kanosue, Kazuyuki

    2015-09-01

    Physical activity contributes to children's physical and mental well-being. Research suggests that active free play helps to maintain and increase physical activity in children and also contributes to social and emotional well-being. To date, these studies have focused on Western countries. Thus, this study was conducted to gain insights into the factors of perceptions of fun, barriers, and facilitators affecting active free play from the perspective of Japanese children using focus group interviews. In Japan, 12 focus groups were conducted with 60 children aged 9-11 years. Children's perceptions of fun in active free play were categorized into socializing, achievement, emotions, and freedom. Additionally, active boys' groups were interested in free play and adventure play; girls' groups were interested in free play with less physical movement and challenges; inactive boys' groups were interested in relaxing and competitive play with bodily contact. However, children mentioned that busy schedules, weather, and health-related factors acted as main barriers. Lastly, children noted facilitators include setting schedules, having access to equipment and playgrounds, and holding special events. The findings provide insights into active free play-related factors for active and inactive Japanese children and also clarify the differences between Japanese and Western children. Such findings will contribute to designing interventions to increase active free play. © The Author(s) 2013.

  18. National energy ombudsman. 2012 activity report

    International Nuclear Information System (INIS)

    Merville, Denis; Lechevin, Bruno; Mialot, Stephane; Lefeuvre, Katia

    2013-06-01

    The National Energy Ombudsman is an independent administrative authority that was created by the law of 7 December 2006 relating to the energy sector, in preparation for the imminent liberalisation of the French gas and electricity markets. It has two legal roles: participating in the process of informing consumers about their rights, and recommending solutions for settling disputes. The Ombudsman reports directly to the French Parliament. This 2012 edition of the National energy ombudsman's activity report has adopted a somewhat original, but very informative, format: an abc which allows us to take a look back at the highlights of 2012 and to summarise the great energy challenges that the National Energy Ombudsman has worked on since 2007: Achievements, Activity, Amicable agreement, Billing decree, Consultation, Disconnections, Energy voucher, National debate on energy transition, help to consumers, lowering gas prices, best management of public resources, communicating gas meter project, Peak hours and off-peak hours, Unpaid bills, Commercially sensitive information, Disputes, Mediation, development of the European Network of Independent Energy Ombudsmen, Combat against energy poverty, Consumer protection, Back billing time limit, Supply quality, Complaint, Recommendations, Debt distress, rise in prices etc

  19. The Immune System Bridges the Gut Microbiota with Systemic Energy Homeostasis: Focus on TLRs, Mucosal Barrier, and SCFAs.

    Science.gov (United States)

    Spiljar, Martina; Merkler, Doron; Trajkovski, Mirko

    2017-01-01

    The gut microbiota is essential for the development and regulation of the immune system and the metabolism of the host. Germ-free animals have altered immunity with increased susceptibility to immunologic diseases and show metabolic alterations. Here, we focus on two of the major immune-mediated microbiota-influenced components that signal far beyond their local environment. First, the activation or suppression of the toll-like receptors (TLRs) by microbial signals can dictate the tone of the immune response, and they are implicated in regulation of the energy homeostasis. Second, we discuss the intestinal mucosal surface is an immunologic component that protects the host from pathogenic invasion, is tightly regulated with regard to its permeability and can influence the systemic energy balance. The short chain fatty acids are a group of molecules that can both modulate the intestinal barrier and escape the gut to influence systemic health. As modulators of the immune response, the microbiota-derived signals influence functions of distant organs and can change susceptibility to metabolic diseases.

  20. Skin barrier homeostasis in atopic dermatitis: feedback regulation of kallikrein activity.

    Directory of Open Access Journals (Sweden)

    Reiko J Tanaka

    Full Text Available Atopic dermatitis (AD is a widely spread cutaneous chronic disease characterised by sensitive reactions (eg. eczema to normally innocuous elements. Although relatively little is understood about its underlying mechanisms due to its complexity, skin barrier dysfunction has been recognised as a key factor in the development of AD. Skin barrier homeostasis requires tight control of the activity of proteases, called kallikreins (KLKs, whose activity is regulated by a complex network of protein interactions that remains poorly understood despite its pathological importance. Characteristic symptoms of AD include the outbreak of inflammation triggered by external (eg. mechanical and chemical stimulus and the persistence and aggravation of inflammation even if the initial stimulus disappears. These characteristic symptoms, together with some experimental data, suggest the presence of positive feedback regulation for KLK activity by inflammatory signals. We developed simple mathematical models for the KLK activation system to study the effects of feedback loops and carried out bifurcation analysis to investigate the model behaviours corresponding to inflammation caused by external stimulus. The model analysis confirmed that the hypothesised core model mechanisms capture the essence of inflammation outbreak by a defective skin barrier. Our models predicted the outbreaks of inflammation at weaker stimulus and its longer persistence in AD patients compared to healthy control. We also proposed a novel quantitative indicator for inflammation level by applying principal component analysis to microarray data. The model analysis reproduced qualitative AD characteristics revealed by this indicator. Our results strongly implicate the presence and importance of feedback mechanisms in KLK activity regulation. We further proposed future experiments that may provide informative data to enhance the system-level understanding on the regulatory mechanisms of skin barrier

  1. Facilitators and barriers to physical activity as perceived by older adults with intellectual disability.

    Science.gov (United States)

    van Schijndel-Speet, Marieke; Evenhuis, Heleen M; van Wijck, Ruud; van Empelen, Pepijn; Echteld, Michael A

    2014-06-01

    Older people with intellectual disability (ID) are characterized by low physical activity (PA) levels. PA is important for reducing health risks and maintaining adequate fitness levels for performing activities of daily living. The aim of this study was to explore preferences of older adults with ID for specific physical activities, and to gain insight into facilitators and barriers to engaging into PA. Fourteen in-depth interviews and four focus groups were undertaken, with a total of 40 older adults with mild and moderate ID included in the analysis. NVivo software was used for analysing the transcribed verbatim interviews. In total, 30 codes for facilitators and barriers were identified. Themes concerning facilitators to PA were enjoyment, support from others, social contact and friendship, reward, familiarity, and routine of activities. Themes concerning barriers to PA were health and physiological factors, lack of self-confidence, lack of skills, lack of support, transportation problems, costs, and lack of appropriate PA options and materials. The results of the present study suggest that older adults with ID may benefit from specific PA programs, adapted to their individual needs and limitations. Results can be used for developing feasible health promotion programs for older adults with ID.

  2. Motivators for and barriers to physical activity in people with knee osteoarthritis: A qualitative study.

    Science.gov (United States)

    Gay, Chloé; Eschalier, Bénédicte; Levyckyj, Christine; Bonnin, Armand; Coudeyre, Emmanuel

    2017-07-27

    We aimed to explore the motivators for and barriers to regular physical activity in people with knee osteoarthritis. We performed a cross-sectional, monocentric qualitative study based on 20 semi-structured individual interviews and two focus groups. People with knee osteoarthritis according to American College of Rheumatology criteria were recruited from spa therapy resorts (Royat, France). Data were collected by interviews, which were then transcribed and coded. The analysis was performed according to the researcher triangulation method. Among the 27 participants (17 women), the mean age was 67years (SD 7.8) and mean body mass index 29.2kg/m 2 (SD 8.2). The motivators for physical activity were physical (well-being, decreased pain, self-perception), personal (lifestyle, psychological well-being), societal (relationships, others' views), and environmental (living). The motivators differed by gender, with the concept of performance predominant for men and others' views for women. The barriers were psychological (fear of pain, lack of motivation) and physical (knee pain, asthenia) and were also potentially related to life events (depression, hospitalization). The study population had an overall positive idea of the value of physical activity for knee osteoarthritis. The participants expressed beliefs and knowledge generally in line with current recommendations. Compliance with these recommendations remains moderate. An educational support for progressive adapted physical activity and identification of barriers and motivators could help improve adherence. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  3. Compensatory mechanisms activated with intermittent energy restriction

    DEFF Research Database (Denmark)

    Coutinho, Sílvia Ribeiro; Halset, Eline Holli; Gåsbakk, Sigrid

    2018-01-01

    Background & aims: Strong compensatory responses, with reduced resting metabolic rate (RMR), increased exercise efficiency (ExEff) and appetite, are activated when weight loss (WL) is achieved with continuous energy restriction (CER), which try to restore energy balance. Intermittent energy...... restriction (IER), where short spells of energy restriction are interspaced by periods of habitual energy intake, may offer some protection in minimizing those responses. We aimed to compare the effect of IER versus CER on body composition and the compensatory responses induced by WL. Methods: 35 adults (age......: 39 ± 9 y) with obesity (BMI: 36 ± 4 kg/m2) were randomized to lose a similar weight with an IER (N = 18) or a CER (N = 17) diet over a 12 week period. Macronutrient composition and overall energy restriction (33% reduction) were similar between groups. Body weight/composition, RMR, fasting...

  4. US-China Clean Energy Research Center on Building Energy Efficiency: Materials that Improve the Cost-Effectiveness of Air Barrier Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hun, Diana E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-12-01

    The US–China Clean Energy Research Center (CERC) was launched in 2009 by US Energy Secretary Steven Chu, Chinese Minister of Science and Technology Wan Gang, and Chinese National Energy Agency Administrator Zhang Guobao. This 5-year collaboration emerged from the fact that the United States and China are the world’s largest energy producers, energy consumers, and greenhouse gas emitters, and that their joint effort could have significant positive repercussions worldwide. CERC’s main goal is to develop and deploy clean energy technologies that will help both countries meet energy and climate challenges. Three consortia were established to address the most pressing energy-related research areas: Advanced Coal Technology, Clean Vehicles, and Building Energy Efficiency (BEE). The project discussed in this report was part of the CERC-BEE consortia; its objective was to lower energy use in buildings by developing and evaluating technologies that improve the cost-effectiveness of air barrier systems for building envelopes.

  5. A prospective examination of exercise and barrier self-efficacy to engage in leisure-time physical activity during pregnancy.

    Science.gov (United States)

    Cramp, Anita G; Bray, Steven R

    2009-06-01

    Pregnant women without medical contraindications should accumulate 30 min of moderate exercise on most days of the week, yet many pregnant women do not exercise at recommended levels. The purpose the study was to examine barriers to leisure-time physical activity (LTPA) and investigate barrier and exercise self-efficacy as predictors of self-reported LTPA during pregnancy. Pregnant women (n = 160) completed questionnaires eliciting barriers to LTPA, measures of exercise and barrier self-efficacy, and 6-week LTPA recall at gestational weeks 18, 24, 30, and 36. A total of 1,168 barriers were content-analyzed, yielding nine major themes including fatigue, time constraints, and physical limitations. Exercise self-efficacy predicted LTPA from gestational weeks 18 to 24 (beta = 0.32, R(2) = 0.26) and weeks 30 to 36 (beta = 0.41, R(2) = 0.37), while barrier self-efficacy predicted LTPA from weeks 24 to 30 (beta = 0.40, R(2) = 0.32). Pregnant women face numerous barriers to LTPA during pregnancy, the nature of which may change substantially over the course of pregnancy. Higher levels of self-efficacy to exercise and to overcome exercise barriers are associated with greater LTPA during pregnancy. Research and interventions to understand and promote LTPA during pregnancy should explore the dynamic nature of exercise barriers and foster women's confidence to overcome physical activity barriers.

  6. Installed Cost Benchmarks and Deployment Barriers for Residential Solar Photovoltaics with Energy Storage: Q1 2016

    Energy Technology Data Exchange (ETDEWEB)

    Ardani, Kristen; O' Shaughnessy, Eric; Fu, Ran; McClurg, Chris; Huneycutt, Joshua; Margolis, Robert

    2016-12-01

    In this report, we fill a gap in the existing knowledge about PV-plus-storage system costs and value by providing detailed component- and system-level installed cost benchmarks for residential systems. We also examine other barriers to increased deployment of PV-plus-storage systems in the residential sector. The results are meant to help technology manufacturers, installers, and other stakeholders identify cost-reduction opportunities and inform decision makers about regulatory, policy, and market characteristics that impede solar plus storage deployment. In addition, our periodic cost benchmarks will document progress in cost reductions over time. To analyze costs for PV-plus-storage systems deployed in the first quarter of 2016, we adapt the National Renewable Energy Laboratory's component- and system-level cost-modeling methods for standalone PV. In general, we attempt to model best-in-class installation techniques and business operations from an installed-cost perspective. In addition to our original analysis, model development, and review of published literature, we derive inputs for our model and validate our draft results via interviews with industry and subject-matter experts. One challenge to analyzing the costs of PV-plus-storage systems is choosing an appropriate cost metric. Unlike standalone PV, energy storage lacks universally accepted cost metrics, such as dollars per watt of installed capacity and lifetime levelized cost of energy. We explain the difficulty of arriving at a standard approach for reporting storage costs and then provide the rationale for using the total installed costs of a standard PV-plus-storage system as our primary metric, rather than using a system-size-normalized metric.

  7. Barriers and enabling factors for work-site physical activity programs: a qualitative examination.

    Science.gov (United States)

    Fletcher, Gena M; Behrens, Timothyh K; Domina, Lorie

    2008-05-01

    Work sites offer a productive setting for physical activity (PA) promoting interventions. Still, PA participation remains low. Thus, the purpose of this study was to examine the reasoning behind commonly reported barriers and enabling factors to participation in PA programs in a work-site setting. Employees from a large city government were recruited to participate in focus groups, stratified by white- and blue-collar occupations. Responses from open-ended questions about factors influencing participation in PA programs were audio recorded and transcribed verbatim. Resulting data were analyzed with open and axial coding. The sample consisted of 60 employees composing 9 focus groups. Although time was the most common barrier between both groups, white-collars workers responded that scheduling and work conflicts were the most common barrier concerning time. Blue-collar workers indicated shift work as their most common barrier. In addition, health was a significant enabling factor for both occupational categories. White-collar workers were much more concerned with appearances and were more highly motivated by weight loss and the hopefulness of quick results than were blue-collar workers. These findings are important in the understanding of PA as it relates to the reasoning behind participation in work-site programs in regard to occupational status.

  8. Deep disposal of high activity radioactive wastes: the study of engineered and geological barriers behaviour

    International Nuclear Information System (INIS)

    Yu Jun; Cui; Delage, P.; Laure, E. de; Behrouz, Gatmiri; Sulem, J.; Anh Minh, Tang

    2008-09-01

    One option for the isolation of high activity and long lived radioactive wastes is the disposal of the vitrified waste containers in galleries dug inside impermeable rocks of the deep underground (granite, argillite, salt). The multi-barrier isolation concept is based on the use of successive barriers to avoid the migration of radionuclides towards the biosphere (container envelope, engineered barrier made of compacted swelling clay, and host rock). In parallel to the works carried out in underground laboratories, experiments and simulation works are performed in order to understand the behaviour of storage facilities and barriers under the effects of constraints, water fluxes and temperature changes. In this context, the UR Navier geotechnical team (CERMES), a joint research unit of Ecole des Ponts ParisTech and LCPC, has been working for more than 15 years on this topic for various contractors. These works are based on original experimental devices allowing to identify the thermo-hydro-mechanical phenomena and thereafter to model them. This dossier presents a summary of these works. (J.S.)

  9. Activation barrier scaling and crossover for noise-induced switching in micromechanical parametric oscillators.

    Science.gov (United States)

    Chan, H B; Stambaugh, C

    2007-08-10

    We explore fluctuation-induced switching in parametrically driven micromechanical torsional oscillators. The oscillators possess one, two, or three stable attractors depending on the modulation frequency. Noise induces transitions between the coexisting attractors. Near the bifurcation points, the activation barriers are found to have a power law dependence on frequency detuning with critical exponents that are in agreement with predicted universal scaling relationships. At large detuning, we observe a crossover to a different power law dependence with an exponent that is device specific.

  10. Physical activity perceptions, context, barriers, and facilitators from a Hispanic child's perspective

    Science.gov (United States)

    Ross, Sharon E. Taverno; Francis, Lori A.

    2016-01-01

    Background In order to develop effective physical activity interventions and to address the burden of obesity in Hispanic children, qualitative studies are needed to build descriptive theory and expand the state of the science. The purpose of this study is to describe physical activity perceptions, context, facilitators, and barriers from the perspective of Hispanic immigrant-origin children. Method This in-depth, ethnographic study included 14, 6- to 11-year old, first- and second- generation Hispanic children recruited from an afterschool program in Southeastern Pennsylvania, USA. Methods included child observation, field notes, semi-structured interviews, and a PhotoVoice activity. Transcripts and field notes were coded and analyzed using the constant comparison method to identify overarching themes and patterns in the data. Results Data analysis yielded four overarching themes regarding children's perspectives on physical activity. Children engaged in a variety of physical activities and sedentary behaviors, which differed by physical (e.g., park, outside home, and afterschool programs) and social (e.g., parents, siblings, and friends) contexts. Children discussed specific benefits of physical activity. Children's negative attitudes toward physical activity were related to physical discomfort, low athletic competence, and safety concerns. Children perceived physical activity and play to be one in the same, and “fun” was identified as a primary driver of physical activity preferences. The facilitators and barriers to physical activity were related to specific parent/home, school, and neighborhood factors. Conclusion Findings from this study suggest that an emphasis on fun and active play, while taking into account family and neighborhood context, may be a desirable intervention approach in Hispanic immigrant-origin children. This study lays the groundwork for future studies to further explore some of the themes identified here to better understand children

  11. Physical activity perceptions, context, barriers, and facilitators from a Hispanic child's perspective

    Directory of Open Access Journals (Sweden)

    Sharon E. Taverno Ross

    2016-08-01

    Full Text Available Background: In order to develop effective physical activity interventions and to address the burden of obesity in Hispanic children, qualitative studies are needed to build descriptive theory and expand the state of the science. The purpose of this study is to describe physical activity perceptions, context, facilitators, and barriers from the perspective of Hispanic immigrant-origin children. Method: This in-depth, ethnographic study included 14, 6- to 11-year old, first- and second- generation Hispanic children recruited from an afterschool program in Southeastern Pennsylvania, USA. Methods included child observation, field notes, semi-structured interviews, and a PhotoVoice activity. Transcripts and field notes were coded and analyzed using the constant comparison method to identify overarching themes and patterns in the data. Results: Data analysis yielded four overarching themes regarding children's perspectives on physical activity. Children engaged in a variety of physical activities and sedentary behaviors, which differed by physical (e.g., park, outside home, and afterschool programs and social (e.g., parents, siblings, and friends contexts. Children discussed specific benefits of physical activity. Children's negative attitudes toward physical activity were related to physical discomfort, low athletic competence, and safety concerns. Children perceived physical activity and play to be one in the same, and “fun” was identified as a primary driver of physical activity preferences. The facilitators and barriers to physical activity were related to specific parent/home, school, and neighborhood factors. Conclusion: Findings from this study suggest that an emphasis on fun and active play, while taking into account family and neighborhood context, may be a desirable intervention approach in Hispanic immigrant-origin children. This study lays the groundwork for future studies to further explore some of the themes identified here to better

  12. Perceived physical activity barriers related to body weight status and sociodemographic factors among Malaysian men in Klang Valley

    Science.gov (United States)

    2013-01-01

    Background Physical inactivity has been acknowledged as a public health issue and has received increasing attention in recent years. This cross-sectional study was conducted to determine the barriers to physical activity among Malaysian men. These barriers were analyzed with regards to sociodemographic factors, physical activity level, BMI and waist circumference. Methods Subjects in this study included 308 Malay men and 422 Chinese men aged 20 years and older. Subjects completed the International Physical Activity Questionnaire (IPAQ) and a questionnaire on barriers to physical activity, categorized into personal and psychological, physical and social environment barriers. Weight, height and waist circumference were also measured and BMI was calculated. Results Descriptive analyses showed that 79.3% of subjects were married, 52.1% had secondary educational level, 68.8% were still working, and 39.7% had household income between RM1500 to RM3500. The perception that other recreational activities with family and friends were more fun was the most frequently reported barrier, followed by weather, lack of discipline, lack of free time, lack of money, and lack of friends. Marriage status, educational level, household income, BMI, and physical activity status were shown to be associated with perceived barriers. Conclusions To increase participation in physical activity, policy makers should consider significant personal, social and environmental barriers when developing appropriate intervention programmes. Health-promoting strategies that increase awareness, knowledge, skills and motivation related to physical activity are required. PMID:23530696

  13. Perceived barriers and enablers of physical activity in postpartum women: a qualitative approach.

    Science.gov (United States)

    Saligheh, Maryam; McNamara, Beverley; Rooney, Rosanna

    2016-06-02

    Postpartum women's recovery from birth can be assisted through increased physical activity (PA). However, women face substantial barriers to participating in exercise and require support to enable them to benefit from increased PA. This study sought to explore women's beliefs about and experiences of PA and exercise during the 6 weeks to 12 months postpartum period. A cohort of 14 postpartum women from a survey study of the barriers and enablers to exercise participation agreed to take part in interview sessions to provide an in-depth understanding of the women's perceptions of the postpartum period and their physical activity during this time. Findings are presented with reference to the social ecological framework and indicate postpartum women face substantial personal and environmental barriers to PA and exercise participation: fatigue, a lack of motivation and confidence, substantial time constraints, lack of access to affordable and appropriate activities and poor access to public transport. In contrast, enablers such as possessing greater social support, in particular partner support, improved PA and exercise participation. The findings encourage facilitation of exercise through mothers' groups, mothers' exercise clubs or postnatal classes suggesting behavioral and social change is needed. Interaction between individuals, community, organizations and policy makers is required. In addition, the provision of specifically tailored and appropriate exercise programs could potentially enable increased PA in postpartum women, thereby improving their health.

  14. Promoting physical activity participation among adolescents: The barriers and the suggestions

    Directory of Open Access Journals (Sweden)

    Niloofar Peykari

    2015-01-01

    Full Text Available Background: Physical activity is a complex behavior. To designing the effective intervention, qualitative researches may be allowed for greater understanding of the reasons behind the adolescences′ physical activity-related behaviors′. Methods: Using the grounded theory approach, including semi-structured focus group discussions (FGDs and in-depth interviews, we conducted a quantitative study to elicit the adolescents and key informants′ opinion regarding the satiation, needs, social and environmental barriers of adolescents′ physical activity. For FGDs, participants were selected from volunteered adolescent (aged 10-19 years of the populated western part of Tehran, which was selected as a research field. Key informants were invited from the health professionals and experts in the field of adolescents′ health. Results: According to findings, although the majority of participants agreed on the important role of physical activity, the lack of essential motivation and the pressure of educational assignments remove it from the daily program priorities. Lack of a safe environment for girls′ physical activity and high cost of professional sports were two first mentioned barriers. It was also suggested that future interventions should focus on improving more parents′ engagement and their direct participation in physical activities with their adolescents. Conclusions: We proposed the participatory strategies for adolescent′s physical activity promotion. Through which target groups participation during the designing, development, and implementation of health programs led to more effective interventions.

  15. Barriers to and motivators for physical activity among people with Type 2 diabetes: patients' perspectives.

    Science.gov (United States)

    Lidegaard, L P; Schwennesen, N; Willaing, I; Faerch, K

    2016-12-01

    To explore barriers to and motivators for physical activity in a group of overweight and obese individuals with dysregulated Type 2 diabetes. Data were collected from the Steno Diabetes Center's outpatient clinic in Denmark. Four focus groups were conducted including 28 individuals with Type 2 diabetes aged 39-71 years. The facilitators used open-ended questions and probes such as images, statements and quotations about physical activity to foster active participation and interaction among participants. Focus groups were recorded on video and the discussions were transcribed and analysed thematically. We identified four main themes: 1) the body as a barrier to physical activity because of functional limitations; 2) logistical challenges, including lack of time and awareness of where to exercise in the local area; 3) being physically active with others, providing a sense of mutual commitment and enjoyment; and 4) goal-setting and self-tracking, which was seen as an opportunity to track physical improvement over time. The findings suggest that, once people are active, a high level of social interaction may help maintain their activity levels. Further research is needed to investigate the effect of combining individually tailored exercise plans with the establishment of customized and locally based exercise communities that offer enjoyment and support. Additionally, it is relevant to explore experiences of using self-tracking technologies to review short- and long-term goals. © 2016 Diabetes UK.

  16. Danish research-active clinical nurses overcome barriers in research utilization.

    Science.gov (United States)

    Adamsen, Lis; Larsen, Kristian; Bjerregaard, Lene; Madsen, Jan K

    2003-03-01

    The aim of this study was to examine whether there was a difference between clinical nurses who were research-active, and clinical nurses who were nonresearch-active in utilization of research. A further aim was to identify the most significant barriers faced by a group of Danish clinical nurses in their use of research. Discrepancy between the improved quality of research results and the lack of implementing them was the starting point for a series of studies which showed the types of barriers clinical nurses found especially cumbersome when applying the research results of other researchers. This study investigates whether the clinical nurses' own engagement in research had any impact on their perception of research utilization. The study had an exploratory and descriptive design. Seventy-nine Danish clinical nurses participated and semi-structured interviewing was used as the research method. There was a statistically significant difference between the research-active and nonresearch-active nurses on various variables. The study showed that, to a larger extent, research-active nurses used evidence-based knowledge and were generally more internationally orientated. Furthermore, two important barriers for research utilization were identified by all 79 clinical nurses included in the study, i.e. 90% of the nurses explained that the quantity of research results was overwhelming, and 75% of them found that they were unable to evaluate the quality of the research. Clinical nurses, who were research-active themselves, experienced more success in overcoming some of the barriers, which existed in applying research to practice. The research potential found amongst clinical nurses in Denmark needed to be further supported through training and guidance in research methodology, establishing introductory stipends and part-time research positions. By doing so, some of the barriers affecting research utilization and the so-called theory-practice gap might be reduced. Further

  17. Hindered rotational energy barriers of BH4- tetrahedra in β-Mg(BH4)2 from quasielastic neutron scattering and DFT calculations

    DEFF Research Database (Denmark)

    Blanchard, Didier; Maronsson, Jon Bergmann; Riktor, M.D.

    2012-01-01

    , around the 2-fold (C2) and 3-fold (C3) axes were observed at temperatures from 120 to 440 K. The experimentally obtained activation energies (EaC2 = 39 and 76 meV and EaC3 = 214 meV) and mean residence times between reorientational jumps are comparable with the energy barriers obtained from DFT......In this work, hindered rotations of the BH4- tetrahedra in Mg(BH4)2 were studied by quasielastic neutron scattering, using two instruments with different energy resolution, in combination with density functional theory (DFT) calculations. Two thermally activated reorientations of the BH4- units...... calculations. A linear dependency of the energy barriers for rotations around the C2 axis parallel to the Mg-Mg axis with the distance between these two axes was revealed by the DFT calculations. At the lowest temperature (120 K) only 15% of the BH4- units undergo rotational motion and from comparison with DFT...

  18. Analysis of active piezoelectric energy harvester

    Directory of Open Access Journals (Sweden)

    Yiliang CUI

    2018-02-01

    Full Text Available Most of the existing piezoelectric traps are designed for a narrow frequency range of vibration, but the surrounding environment has a very wide frequency range, and the frequency may also be subject to change, causing the problem of difficult to achieve energy capture or capture inefficiency. In order to solve problem, a new T-type piezoelectric cantilever is proposed as a capture energy structure in the paper. To begin with the aspects of structural design and circuit design, the static analysis, modal analysis and resonance analysis of the structure are carried out and the natural frequency and excitation frequency of the device are analyzed. The design and calculation of the power consumption and the loss of the components of the circuit are analyzed by the simulation and verification of the active capture energy circuit, and the active and passive techniques are compared and analyzed, the simulation of the active capture circuit is verified by analyzing the power consumption of the circuit and the maximum power obtained by the active technology is 5 times of that of the passive technology. And then the voltage-controlled active boundary control method can be used for interface circuit design, taking the initiative to use each piezoelectric transduction cycle triggered by the electrical boundary conditions to effectively increase the input piezoelectric pump energy, and then increase output power. The way of utilizing the active trapping of piezoelectric materials is innovated, which has a positive effect on the development of piezoelectric traps.

  19. Renewable energy activities in Senegal: a review

    International Nuclear Information System (INIS)

    Youm, I.; Sarr, J.; Kane, M.M.; Sall, M.

    2000-01-01

    Like many countries in Africa, Senegal is facing economical decline, energy crisis and serious desertification problem in rural areas. These issues could be removed if renewable energy is used as a primary source of energy in rural areas. What is required is a strategy to implement renewable energy technologies at large scale. The government and many non-governmental organisations (NGOs) have tried to comprehend and have strived to address the problem of energy. This paper present a review of activities in the field of renewable energy applications in Senegal, which goes back to the mid 1970s and will discuss the socio-economic benefits that the country has derived from these environmentally sound and appropriate sources of energy. The development and trial of systems were mostly funded so far by donor agencies in collaboration with government and NGOs. Among the applications being supported are solar lighting, water pumping and small power plants. Recent efforts have been aimed at restructuring the programmes and giving them a market orientation. Future trends, some suggestion and recommendations for successful dissemination of renewable energy sources are also drawn. The present situation is seen to be much more promising and favourable for renewable energy. (Author)

  20. Dual energy radiography using active detector technology

    International Nuclear Information System (INIS)

    Seibert, J.A.; Poage, T.F.; Alvarez, R.E.

    1996-01-01

    A new technology has been implemented using an open-quotes active-detectorclose quotes comprised of two computed radiography (CR) imaging plates in a sandwich geometry for dual-energy radiography. This detector allows excellent energy separation, short exposure time, and high signal to noise ratio (SNR) for clinically robust open-quotes bone-onlyclose quotes and open-quotes soft-tissue onlyclose quotes images with minimum patient motion. Energy separation is achieved by two separate exposures at widely different kVp's: the high energy (120 kVp + 1.5 mm Cu filter) exposure is initiated first, followed by a short burst of intense light to erase the latent image on the front plate, and then a 50 kVp (low energy) exposure. A personal computer interfaced to the x-ray generator, filter wheel, and active detector system orchestrates the acquisition sequence within a time period of 150 msec. The front and back plates are processed using a CR readout algorithm with fixed speed and wide dynamic range. open-quotes Bone-onlyclose quotes and open-quotes soft-tissue onlyclose quotes images are calculated by geometric alignment of the two images and application of dual energy decomposition algorithms on a pixel by pixel basis. Resultant images of a calibration phantom demonstrate an increase of SNR 2 / dose by ∼73 times when compared to a single exposure open-quotes passive-detectorclose quotes comprised of CR imaging plates, and an ∼8 fold increase compared to a screen-film dual-energy cassette comprised of different phosphor compounds. In conclusion, dual energy imaging with open-quotes active detectorclose quotes technology is clinically feasible and can provide substantial improvements over conventional methods for dual-energy radiography

  1. Free-Energy Barrier of Filling a Spherical Cavity in the Presence of Line Tension: Implication to the Energy Barrier between the Cassie and Wenzel States on a Superhydrophobic Surface with Spherical Cavities.

    Science.gov (United States)

    Iwamatsu, Masao

    2016-09-20

    The free-energy barrier of filling a spherical cavity having an inner wall of various wettabilities is studied. The morphology and free energy of a lens-shaped droplet are determined from the minimum of the free energy. The effect of line tension on the free energy is also studied. Then, the equilibrium contact angle of the droplet is determined from the generalized Young's equation. By increasing the droplet volume within the spherical cavity, the droplet morphology changes from spherical with an equilibrium contact angle of 180° to a lens with a convex meniscus, where the morphological complete drying transition occurs. By further increasing the droplet volume, the meniscus changes from convex to concave. Then, the lens-shaped droplet with concave meniscus spreads over the whole inner wall, resulting in an equilibrium contact angle of 0° to leave a spherical bubble, where the morphological complete wetting transition occurs. Finally, the whole cavity is filled with liquid. The free energy shows a barrier from complete drying to complete wetting as a function of droplet volume, which corresponds to the energy barrier between the Cassie and Wenzel states of the superhydrophobic surface with spherical cavities. The free-energy maximum occurs when the meniscus of the droplet becomes flat, and it is given by an analytic formula. The effect of line tension is expressed by the scaled line tension, and this effect is largest at the free-energy maximum. The positive line tension increases the free-energy maximum, which thus increases the stability of the Cassie superhydrophobic state, whereas the negative line tension destabilizes the superhydrophobic state.

  2. Commission of energy regulation. 2004 activity report

    International Nuclear Information System (INIS)

    2004-01-01

    The commission of energy regulation (CRE) is an independent administrative authority in charge of the control of the operation of gas and electricity markets. This document is the fifth activity report of CRE and covers the July 1, 2003 - June 30, 2004 period, which corresponds to the era of opening of energy markets as a consequence of the enforcement of the June 26, 2003 European directive. In the framework of the stakes made by energy markets liberalization, this document presents the situation of the gas and electricity markets during this period (European framework, regulation of both markets, public utility mission..) and describes CRE's means for the monitoring of these markets. (J.S.)

  3. Driving forces and barriers to improved energy performance of buildings: an analysis of energy performance of Swedish buildings, 2000-2006

    Energy Technology Data Exchange (ETDEWEB)

    Fuglseth, Bente Beckstroem

    2008-06-15

    The building sector is responsible for a substantial part of energy use and green house gas emissions in Europe. This report explores driving forces and barriers to improved energy performance of buildings, using the Swedish building sector as a case. The development of energy performance of buildings in Sweden from 2000 until 2006 is explored by applying a threefold understanding of energy performance of buildings: substitution from fossil fuels to renewable energy, conversion from electrical heating to thermal energy and reduction in energy demand. Three explanatory approaches are used to analyse driving forces and