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Sample records for benefits scheme pbs

  1. Band-structure tailoring and surface passivation for highly efficient near-infrared responsive PbS quantum dot photovoltaics

    Science.gov (United States)

    Zhou, Ru; Niu, Haihong; Ji, Fengwei; Wan, Lei; Mao, Xiaoli; Guo, Huier; Xu, Jinzhang; Cao, Guozhong

    2016-11-01

    PbS is a promising light harvester for near-infrared (NIR) responsive quantum dot (QD) photovoltaics due to its narrow bulk band gap (0.41 eV) and large exciton Bohr radius (18 nm). However, the relatively low conduction band (CB) and high-density surface defects of PbS as two major drawbacks for its use in solar cells severely hamper the photovoltaic performance enhancement. In this work, a modified solution-based successive ionic layer adsorption and reaction (SILAR) utilizing mixed cationic precursors of Pb2+ and Cd2+ is explored, and such a scheme offers two benefits, band-structure tailoring and surface passivation. In-situ deposited CdS suppresses the excessive growth of PbS in the mesopores, thereby facilitating the favorable electron injection from PbS to TiO2 in view of the up-shifted CB level of QDs; the intimate interpenetration of two sulfides with each other leads to superior passivation of trap state defects on PbS, which suppresses the interfacial charge recombination. With the construction of photovoltaics based on such a hybrid (Pb,Cd)S/CdS configuration, impressive power conversion efficiency up to 4.08% has been reached, outperforming that of the conventional PbS/CdS pattern (2.95%). This work highlights the great importance of band-structure tailoring and surface passivation for constructing highly efficient PbS QD photovoltaics.

  2. Solvent Engineering for High-Performance PbS Quantum Dots Solar Cells

    Directory of Open Access Journals (Sweden)

    Rongfang Wu

    2017-07-01

    Full Text Available PbS colloidal quantum dots (CQDs solar cells have already demonstrated very impressive advances in recent years due to the development of many different techniques to tailor the interface morphology and compactness in PbS CQDs thin film. Here, n-hexane, n-octane, n-heptane, isooctane and toluene or their hybrids are for the first time introduced as solvent for comparison of the dispersion of PbS CQDs. PbS CQDs solar cells with the configuration of PbS/TiO2 heterojunction are then fabricated by using different CQDs solution under ambient conditions. The performances of the PbS CQDs solar cells are found to be tuned by changing solvent and its content in the PbS CQDs solution. The best device could show a power conversion efficiency (PCE of 7.64% under AM 1.5 G illumination at 100 mW cm−2 in a n-octane/isooctane (95%/5% v/v hybrid solvent scheme, which shows a ~15% improvement compared to the control devices. These results offer important insight into the solvent engineering of high-performance PbS CQDs solar cells.

  3. Private health insurance and the Pharmaceutical Benefits Scheme: how effective has recent government policy been?

    Science.gov (United States)

    Richardson, Jeff R J; Segal, Leonie

    2004-01-01

    The cost to government of the Pharmaceutical Benefits Scheme (PBS) is rising at over 10 percent per annum. The government subsidy to Private Health Insurance (PHI) is about $2.4 billion and rising. Despite this, the queues facing public patients - which were the primary justification for the assistance to PHI - do not appear to be shortening. Against this backdrop, we seek to evaluate recent policies. It is shown that the reason commonly given for the support of PHI - the need to preserve the market share of private hospitals and relieve pressure upon public hospitals - is based upon a factually incorrect analysis of the hospital sector in the last decade. It is similarly true that the 'problem' of rising pharmaceutical expenditures has been exaggerated. The common element in both sets of policies is that they result in cost shifting from the public to the private purse and have little to do with the quality or quantity of health services.

  4. Minimum Benefits for HIV/AIDS in South African Medical Schemes ...

    African Journals Online (AJOL)

    ... to the Minister of Health in respect of the extent of prescribed minimum benefits for HIV/AIDS. Medical schemes are required to provide the PMBs to their members without limits or co-payments. Keywords: Medical schemes; HIV; AIDS; benefits; prescribed minimum benefits. South African Actuarial Journal: 2003 3: 77-112 ...

  5. Reinforcement effect of poly(butylene succinate) (PBS)-grafted cellulose nanocrystal on toughened PBS/polylactic acid blends.

    Science.gov (United States)

    Zhang, Xuzhen; Zhang, Yong

    2016-04-20

    Poly(butylene succinate) (PBS)/polylactic acid (PLA) blends modified with dicumyl peroxide (DCP) were reinforced by PBS-g-cellulose nanocrystal (CNC) through melt mixing. PBS-g-CNC was prepared through in situ polymerization and its structure was confirmed by FTIR, (13)C NMR, XPS and GPC analysis after saponification. The morphological analysis of PBS/PLA/PBS-g-CNC composites before and after etched by CH2Cl2 shows that the addition of DCP and PBS-g-CNC could decrease the size of PBS as a dispersed phase in PLA matrix and improve the dispersion of PBS-g-CNC in both PBS and PLA phases, which could affect the crystallization and mechanical properties of composites. The crystallinity of PLA α'-phase crystal in PBS/PLA/PBS-g-CNC composites is increased obviously by the addition of PBS-g-CNC, leading to an increase of the crystallinity of the composites. PBS/PLA blends modified by DCP have high Notched Izod impact strength and moduli, and the values are increased by the addition of PBS-g-CNC. Both storage modulus and glass translation temperature of PBS/PLA blend are increased by DCP and PBS-g-CNC, which is proved by DMA results, showing a weak molecular segment mobility of PBS/PLA matrix. The addition of DCP decreases the crystallization temperature and crystallinity of PBS/PLA composite, but increases the thermal stability of composites, mostly because of the crosslink effect of DCP on PBS/PLA matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Hierarchical Markov Model in Life Insurance and Social Benefit Schemes

    Directory of Open Access Journals (Sweden)

    Jiwook Jang

    2018-06-01

    Full Text Available We explored the effect of the jump-diffusion process on a social benefit scheme consisting of life insurance, unemployment/disability benefits, and retirement benefits. To do so, we used a four-state Markov chain with multiple decrements. Assuming independent state-wise intensities taking the form of a jump-diffusion process and deterministic interest rates, we evaluated the prospective reserves for this scheme in which the individual is employed at inception. We then numerically demonstrated the state of the reserves for the scheme under jump-diffusion and non-jump-diffusion settings. By decomposing the reserve equation into five components, our numerical illustration indicated that an extension of the retirement age has a spillover effect that would increase government expenses for other social insurance programs. We also conducted sensitivity analyses and examined the total-reserves components by changing the relevant parameters of the transition intensities, which are the average jump-size parameter, average jump frequency, and diffusion parameters of the chosen states, with figures provided. Our computation revealed that the total reserve is most sensitive to changes in average jump frequency.

  7. Developing benefit schemes and financial compensation measures for fishermen impacted by marine renewable energy projects

    International Nuclear Information System (INIS)

    Reilly, Kieran; O’Hagan, Anne Marie; Dalton, Gordon

    2016-01-01

    Commercial fishermen are arguably the stakeholder group most likely to be directly impacted by the expansion of the marine renewable energy (MRE) sector. The potential opposition of fishermen may hinder the development of MRE projects and the provision of benefit schemes could to enhance acceptance. Benefit schemes refer to additional voluntary measures that are provided by a developer to local stakeholders. The aim of this study is to explore the issue of the provision of benefit packages to local fishing communities and financial compensation measures for fishermen who may be impacted by MRE projects. Semi-structured interviews were conducted with fourteen fishermen from three separate case study sites around the island of Ireland where MRE projects were being developed. In addition, ten company fisheries liaison officers (CFLOs) who have worked on MRE projects in the UK and Ireland were also interviewed. The interviews were analysed under the headings of local employment, benefits in kind, compensation and community funds and ownership of projects. Analysis shows that there is uncertainty among fishermen over whether they would benefit or gain employment from MRE. Provision of re-training schemes and preferential hiring practices could be used by MRE developers to reduce this uncertainty. There was also agreement between fishermen and CFLOs on the need for the provision of an evidence-base and a standard approach for the calculation of disruption payments. A formal structure for the provision of benefit schemes for fishermen would be useful. Furthermore, schemes that provide a range of benefits to fishermen and other stakeholders over the lifetime of a MRE project are more likely to be successful at enhancing acceptance. - Highlights: • There is uncertainty among fishermen over benefits from MRE projects. • Re-training is required for fishermen to avail of employment opportunities. • Evidence-base is required for calculation of disruption payments.

  8. Review on PCL, PBS, and PCL/PBS blends containing carbon nanotubes

    Directory of Open Access Journals (Sweden)

    T. P. Gumede

    2018-06-01

    Full Text Available Biodegradable polymers received considerable attention due to their contribution in the reduction of environmental concerns and the realization that global petroleum resources are finite. The development of double crystalline biobased blends such as poly(ε-caprolactone (PCL and poly(butylene succinate (PBS are particularly interesting because each component has an influence on the crystallization behaviour of the other component, and thus influences the strength and mechanical properties of a polymer blend. The lack of miscibility between PCL and PBS constitutes a bottleneck, and efforts have been made to improve the miscibility through the inclusion of copolymers. Having realized that incorporating conductive nanofillers such as carbon nanotubes (CNTs, (especially when the CNTs are functionalized or used as a masterbatch i.e., polycarbonate/MWCNTs masterbatch, into biopolymer matrices, can enhance the thermal and mechanical properties, as well as electrical and thermal conductivity, a lot of research was aimed at the production of bionanocomposites. This review paper discusses the properties of PCL, PBS, their blends, and their CNTs containing nanocomposites.

  9. Who benefits from the Obio Community Health Insurance Scheme in Rivers State, Nigeria? A benefit incidence analysis.

    Science.gov (United States)

    Vaughan, Kelsey; Akwataghibe, Ngozi; Fakunle, Babatunde; Wolmarans, Liezel

    2016-11-01

    A key aspect of monitoring and evaluating health programs is ensuring that benefits are reaching their target population. We conducted a benefit incidence analysis (BIA) of a Shell-sponsored community health insurance scheme in Nigeria to determine the extent to which the target group (the poor) was benefitting. We examined a sample of 616 patients' hospital attendance, financial and administrative records from 2012-2013. We estimated annual utilization rates and average unit costs for inpatient and outpatient services. We multiplied the two to produce a total cost per patient, then deducted annual out-of-pocket expenditures to estimate the total community-based health insurance scheme benefit per person. Benefits were multiplied by the total number of persons in each socioeconomic group to aggregate benefits. We used concentration curves and dominance tests to determine statistical significance at 5% and 10% levels of significance. Collectively, the poorest 20% of the population received 12% of benefits while the richest quintile received the largest share (23%). Inpatient and outpatient benefits are weakly regressive (pro-rich), statistically significant at a 10% level of significance. Although the poor were found to benefit, this BIA revealed a tendency towards pro-rich distributions. Removing co-payments for the poorest, reducing long wait and visit times and using community volunteers to help increase access to health services may improve benefits for the poor. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Monitoring system for OpenPBS environment

    Energy Technology Data Exchange (ETDEWEB)

    Kolosov, V. [ITEP, Moscow (Russian Federation)]. E-mail: victor.kolosov@itep.ru; Lublev, Y. [ITEP, Moscow (Russian Federation); Makarychev, S. [ITEP, Moscow (Russian Federation)

    2004-11-21

    The OpenPBS batch system is widely used in the HEP community. The Open PBS package has a set of tools to check the current status of the system. This information is useful, but it is not sufficient enough for resource accounting and planning. As a solution for this problem, we developed a monitoring system which parses the logfiles from OpenPBS and stores the information into a SQL database (PostgreSQL). This allows us to analyze the data in many different ways using SQL queries. The system was used in ITEP during the last two years for batch farm monitoring.

  11. Facile synthesis of organically capped PbS nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Nejo, Ayorinde O.; Nejo, Adeola A.; Pullabhotla, Rajasekhar V.S.R. [Department of Chemistry, University of Zululand, Private Bag X1001, Kwadlangezwa (South Africa); Revaprasadu, Neerish, E-mail: nrevapra@pan.uzulu.ac.za [Department of Chemistry, University of Zululand, Private Bag X1001, Kwadlangezwa (South Africa)

    2012-10-05

    Highlights: Black-Right-Pointing-Pointer Hexadecylamine and tri-n-octylphosphine oxide capped PbS nanoparticles have been synthesized. Black-Right-Pointing-Pointer By varying the reaction conditions various morphologies were formed. Black-Right-Pointing-Pointer The formation of the anisotropic particles is due to different growth mechanisms. - Abstract: PbS nanocubes and nanorods were successfully synthesized through a facile route using hexadecylamine (HDA) and tri-n-octylphosphine oxide (TOPO) as surfactants. The structure and morphology of the as-prepared PbS nanocrystals were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution TEM. The morphology of the PbS was influenced by the variation in lead source and organic surfactant. Particles in the shape of spheres, perfect cubes and rods were obtained by variation in reaction conditions. A possible growth mechanism to explain the formation of these PbS nanocubes and nanorods is also discussed.

  12. PBS in the service of ecology

    International Nuclear Information System (INIS)

    Stiegel, J.

    1999-01-01

    In this paper the activities of PBS Banska Bystrica, Ltd., in the service ecology are presented. PBS is fundamentally oriented toward repairs to and maintenance of original products of Prvni brnenska strojirna, including spare parts, as well as modernization and ecologization of heat-energy operations using low-emission combustion equipment, cogeneration units for steam-gas processes and high efficient technological process control systems. In connection with company's profile the prospectus expressed with a sum of 80 million Slovak crowns in orders accepted for 1998 was exceed by 15 million Slovak crowns and despite a bad situation on the Slovak financial market the company is functioning in the first year of its activity without credits. In the perspective by 2000 PBS plans to obtain 200 million Slovak crowns worth orders

  13. Field effect transistors and phototransistors based upon p-type solution-processed PbS nanowires

    Science.gov (United States)

    Giraud, Paul; Hou, Bo; Pak, Sangyeon; Inn Sohn, Jung; Morris, Stephen; Cha, SeungNam; Kim, Jong Min

    2018-02-01

    We demonstrate the fabrication of solution processed highly crystalline p-type PbS nanowires via the oriented attachment of nanoparticles. The analysis of single nanowire field effect transistor (FET) devices revealed a hole conduction behaviour with average mobilities greater than 30 cm2 V-1 s-1, which is an order of magnitude higher than that reported to date for p-type PbS colloidal nanowires. We have investigated the response of the FETs to near-infrared light excitation and show herein that the nanowires exhibited gate-dependent photo-conductivities, enabling us to tune the device performances. The responsivity was found to be greater than 104 A W-1 together with a detectivity of 1013 Jones, which benefits from a photogating effect occurring at negative gate voltages. These encouraging detection parameters are accompanied by relatively short switching times of 15 ms at positive gate voltages, resulting from a combination of the standard photoconduction and the high crystallinity of the nanowires. Collectively, these results indicate that solution-processed PbS nanowires are promising nanomaterials for infrared photodetectors as well as p-type nanowire FETs.

  14. Stochastic Actuarial Modelling of a Defined-Benefit Social Security Pension Scheme: An Analytical Approach

    OpenAIRE

    Iyer, Subramaniam

    2017-01-01

    Among the systems in place in different countries for the protection of the population against the long-term contingencies of old-age (or retirement), disability and death (or survivorship), defined-benefit social security pension schemes, i.e. social insurance pension schemes, by far predominate, despite the recent trend towards defined-contribution arrangements in social security reforms. Actuarial valuations of these schemes, unlike other branches of insurance, continue to be carried out a...

  15. Structural characterization of chemically deposited PbS thin films

    International Nuclear Information System (INIS)

    Fernandez-Lima, F.A.; Gonzalez-Alfaro, Y.; Larramendi, E.M.; Fonseca Filho, H.D.; Maia da Costa, M.E.H.; Freire, F.L.; Prioli, R.; Avillez, R.R. de; Silveira, E.F. da; Calzadilla, O.; Melo, O. de; Pedrero, E.; Hernandez, E.

    2007-01-01

    Polycrystalline thin films of lead sulfide (PbS) grown using substrate colloidal coating chemical bath depositions were characterized by RBS, XPS, AFM and GIXRD techniques. The films were grown on glass substrates previously coated with PbS colloidal particles in a polyvinyl alcohol solution. The PbS films obtained with the inclusion of the polymer showed non-oxygen-containing organic contamination. All samples maintained the Pb:S 1:1 stoichiometry throughout the film. The amount of effective nucleation centers and the mean grain size have being controlled by the substrate colloidal coating. The analysis of the polycrystalline PbS films showed that a preferable (1 0 0) lattice plane orientation parallel to the substrate surface can be obtained using a substrate colloidal coating chemical bath deposition, and the orientation increases when a layer of colloid is initially dried on the substrate

  16. Patterns and trends of potentially inappropriate high-density lipoprotein cholesterol testing in Australian adults at high risk of cardiovascular disease from 2008 to 2014: analysis of linked individual patient data from the Australian Medicare Benefits Schedule and Pharmaceutical Benefits Scheme.

    Science.gov (United States)

    Hajati, Farshid; Atlantis, Evan; Bell, Katy J L; Girosi, Federico

    2018-03-08

    We examine the extent to which the adult Australian population on lipid-lowering medications receives the level of high-density lipoprotein cholesterol (HDL-C) testing recommended by national guidelines. We analysed records from 7 years (2008-2014) of the 10% publicly available sample of deidentified, individual level, linked Medicare Benefits Schedule (MBS) and Pharmaceutical Benefits Scheme (PBS) electronic databases of Australia. The PBS data were used to identify individuals on stable prescriptions of lipid-lowering treatment. The MBS data were used to estimate the annual frequency of HDL-C testing. We developed a methodology to address the issue of 'episode coning' in the MBS data, which causes an undercounting of pathology tests. We used a published figure on the proportion of unreported HDL-C tests to correct for the undercounting and estimate the probability that an HDL-C test was performed. We judged appropriateness of testing frequency by comparing the HDL-C testing rate to guidelines' recommendations of annual testing for people at high risk for cardiovascular disease. We estimated that approximately 49% of the population on stable lipid-lowering treatment did not receive any HDL-C test in a given year. We also found that approximately 19% of the same population received two or more HDL-C tests within the year. These levels of underutilisation and overutilisation have been changing at an average rate of 2% and -4% a year, respectively, since 2009. The yearly expenditure associated with test overutilisation was approximately $A4.3 million during the study period, while the cost averted because of test underutilisation was approximately $A11.3 million a year. We found that approximately half of Australians on stable lipid-lowering treatment may be having fewer HDL-C testing than recommended by national guidelines, while nearly one-fifth are having more tests than recommended. © Article author(s) (or their employer(s) unless otherwise stated in the text

  17. A novel electrochemical preparation of PbS nanoparticles

    International Nuclear Information System (INIS)

    Yang Yujun

    2006-01-01

    A simple one-step anodic sonoelectrochemical method to synthesize PbS nanoparticles has been developed. With the lead foil as the sacrificing anode, Pb(II) was anodically dissolved from the lead electrode into the aqueous solution of sodium sulfide, supporting electrolyte (potassium nitrate) and capping agent (PVA) at a constant potential, and then the produced Pb(II) reacted with the sulfide anion to form PbS nanoparticles under ultrasonic irradiation. The effects of the applied potential, capping agent and ultrasound in the formation of PbS nanoparticles are discussed, and the results suggest that the anodic sonoelectrochemical method may be a general and convenient way to prepare metal sulfide nanoparticles

  18. Self-assembled colloidal PbS quantum dots on GaAs substrates

    International Nuclear Information System (INIS)

    Lue, Wei; Yamada, Fumihiko; Kamiya, Itaru

    2010-01-01

    We report the fabrication and analysis of self-assembled monolayer and bilayer films of colloidal PbS quantum dots (QDs) on GaAs (001) substrates. 1,6-hexanedithiol is used as link molecule between QDs and GaAs substrates. Atomic force microscopy (AFM) and photoluminescence (PL) measurements confirm the formation of PbS QD film on GaAs. For the monolayer PbS QD film, the temperature-dependent PL shows a feature typical of close-packed film. For the bilayer PbS QD film fabricated from two different mean-sized PbS QDs, we find that the stacking sequence of QDs with different size affects the quantum yield and emission wavelength of the film.

  19. A simple route for making surfactant free lead sulfide (PbS) quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Firoz; Kumar, Neetesh; Dutta, Viresh, E-mail: vdutta@ces.iitd.ac.in

    2015-05-15

    Highlights: • Surfactant free PbS NCs were successfully synthesised using CoSP technique. • The technique eliminates the requirements of washing to remove the ligands. • Grinding using mortar and pestle creates well separated PbS QDs. • Surfactant free PbS NCs are stable and do not show any degradation with time. - Abstract: An efficient, cost effective and less time consuming method suitable for mass production of surfactant free quantum dots (QDs) of lead sulfide (PbS) is reported. PbS nanocrystals (NCs) are first synthesised by continuous spray pyrolysis (CoSP) technique and de-agglomeration into PbS quantum dots (QDs) is achieved by vigorous mechanical grinding using mortar and pestle. Lead acetate and thiourea were used as the precursor materials for preparation of surfactant free PbS NCs. The broadening in XRD peaks of ground NCs as compared to as synthesized PbS NCs clearly indicated the reduction in particle size to be QDs of PbS. The TEM images also showed that ground PbS NCs were nearly spherical in shape having an average diameter in the range of 4–6 nm. The shift in optical gap from 0.41 eV to 1.47 eV supported the QD formation.

  20. National health insurance scheme: Are the artisans benefitting in Lagos state, Nigeria?

    Directory of Open Access Journals (Sweden)

    Princess C Campbell

    2016-01-01

    Full Text Available Background: Health insurance (HI can serve as a vital risk protection for families and small businesses and also increase access to priority health services. This study determined the knowledge, attitude of artisans toward HI as well as their health-seeking pattern and willingness to join the HI scheme. Methodology: This descriptive cross-sectional survey used a multistage sampling technique to recruit 260 participants, using self-designed, pretested, interviewer-administered questionnaire. Data were analyzed using Epi-info version 7.0. Chi-square test, Fisher′s exact test, and logistic regression were used for associations; the level of significance was set at 5%. Results: The respondents were predominantly male, i.e., 195 (75.0%, with a mean age of 32.36 + 6.20 years and mean income of N 29,000 + 5798.5 ($1 ~ N 161. Majority of the respondents, i.e., 226 (86.9% were not aware of HI. The overall knowledge was poor (6.5% and the main source of information was through radio/television (41.2%. Nearly, half of the respondents (33 out of 67 identified the concept of HI as a pool of contributors′ fund for only healthcare service. A high proportion of the respondents (27 out of 34 were aware of the benefits of HI, although majority, i.e., 27 (79.4% identified access to medication as the benefit. The majority of the respondents, i.e., 228 (87.7% expressed negative attitude toward the scheme; however, 76.5% were willing to join the HI scheme. Conclusion: The artisans had low awareness/poor knowledge of HI which translated to a negative attitude toward the scheme. There is need for an aggressive stakeholders′ enlightenment campaign for increasing coverage.

  1. Modeling the PbS quantum dots complex dielectric function by adjusting the E-k diagram critical points of bulk PbS

    Science.gov (United States)

    Hechster, Elad; Sarusi, Gabby

    2017-07-01

    The complex dielectric function ɛ(E )=ɛR(E )+i ɛI(E ) of a semiconductor is a key parameter that dictates the material's optical and electrical properties. Surprisingly, the ɛ(E ) of Lead Sulfide (PbS) quantum dots (QDs) has not been widely studied. In the present work, we develop a new model that aims to simulate the ɛ(E ) of QDs. Our model is based on the fact that the quantum confinement in the nano regime affects all the electronic transitions throughout the entire Brillouin zone. Hence, as a first approximation, we attribute an equal contribution of energy, equivalent to the bandgap broadening, to each critical point (CP) in the E-k diagram. This is mathematically realized by adding these energy contributions to the central energy parameters of the Lorentz oscillator model. In order to validate our model, we used the CP parameters of bulk PbS to simulate the ɛ(E ) of PbS QDs. Next, we use Maxwell Relations to calculate the refractive index and the extinction coefficient of PbS QDs from ɛ(" separators="|E ). Our results were compared with those published in the previous literature and showed good agreement. Our findings open a new avenue that may enable the calculation of the ɛ(" separators="|E ) for nanoparticle systems.

  2. Nongeminate radiative recombination of free charges in cation-exchanged PbS quantum dot films

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Ashley R. [National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401 (United States); Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309 (United States); Beard, Matthew C.; Johnson, Justin C. [National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401 (United States)

    2016-06-01

    Highlights: • Photoluminescence and transient absorption are used to probe PbS QD films. • Cation-exchanged PbS QDs show room-temperature PL emission. • Bimolecular recombination is shown for the first time in coupled, PbS QD films. - Abstract: Using photoluminescence (PL) spectroscopy we explore the radiative recombination pathways in PbS quantum dots (QDs) synthesized by two methods. We compare conventionally synthesized PbS from a PbO precursor to PbS synthesized using cation-exchange from CdS QDs. We show that strongly coupled films of PbS QDs from the cation-exchange luminesce with significant efficiency at room temperature. This is in stark contrast to conventional PbS QDs, which have exceedingly weak room temperature emission. Moreover, the power dependence of the emission is quadratic, indicating bimolecular radiative recombination that is reasonably competitive with trap-assisted recombination, a feature previously unreported in coupled PbS QD films. We interpret these results in terms of a greatly reduced defect concentration for cation-exchanged QDs that mitigates the influence of trap-assisted recombination. Cation-exchanged QDs have recently been employed in highly efficient and air-stable lead chalcogenide QD devices, and the reduced number of trap states inferred here may lead to improved current collection and higher open circuit voltage.

  3. Performance-based standards (PBS) vehicles for transport in the agricultural sector

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2008-07-01

    Full Text Available manufacturers start designing vehicles on an ad hoc basis. It should be borne in mind that PBS vehicle designs include certain safety features, and must be loaded in the correct manner. The RTMS approach offers the most suitable way of ensuring.... The objectives of the Performance-Based Standards (PBS) philosophy are to utilise technology to reduce road damage, improve safety, increase payloads and reduce costs. To overcome the limitations of prescriptive legislation, is has been proposed that PBS...

  4. Study of the back recombination processes of PbS quantum dots sensitized solar cells

    Science.gov (United States)

    Badawi, Ali; Al-Hosiny, N.; Merazga, Amar; Albaradi, Ateyyah M.; Abdallah, S.; Talaat, H.

    2016-12-01

    In this study, the back recombination processes of PbS quantum dots sensitized solar cells (QDSSCs) has been investigated. PbS QDs were adsorbed onto titania electrodes to act the role of sensitizers using successive ionic layer adsorption and reaction (SILAR) technique. The energy band gaps of the synthesized PbS QDs/titania are ranged from 1.64 eV (corresponding to 756 nm) to 3.12 eV (397 nm) matching the whole visible solar spectrum. The hyperbolic band model (HBM) was used to calculate PbS QDs size and it ranges from 1.76 to 3.44 nm. The photovoltaic parameters (open circuit voltage Voc, short circuit current density Jsc, fill factor FF and efficiency η) of the assembled PbS QDs sensitized solar cells (QDSSCs) were determined under a solar illumination of 100 mW/cm2 (AM 1.5 conditions). The open circuit voltage-decay (OCVD) rates of the assembled PbS QDSSCs were measured. The time constant (τ) for PbS QDSSCs (4 SILAR cycles) shows one order of magnitude larger than that of PbS QDSSCs (8 SILAR cycles) as a result of a decreased electron-hole back recombination.

  5. Oleic acid capped PbS nanoparticles: Synthesis, characterization and tribological properties

    International Nuclear Information System (INIS)

    Chen Shuang; Liu Weimin

    2006-01-01

    Oleic acid (OA) capped PbS nanoparticles were chemically synthesized and characterized by means of Fourier transform-infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray electron diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The triboligical properties of the capped PbS nanoparticles as additive in liquid paraffin was investigated using a four-ball machine. The lubricating mechanisms were discussed along with the analyses results of XPS and scanning electron microscope (SEM). Results show that OA-capped PbS nanoparticles, with an average diameter of about 8 nm, are able to prevent water adsorption, oxidation and are capable of being dispersed stably in organic solvents or mineral oil. OA-capped PbS nanoparticles as an additive in liquid paraffin perform good antiwear and friction-reduction properties owing to the formation of a boundary film

  6. Inorganic-ligand exchanging time effect in PbS quantum dot solar cell

    International Nuclear Information System (INIS)

    Kim, Byung-Sung; Hong, John; Hou, Bo; Cho, Yuljae; Sohn, Jung Inn; Cha, SeungNam; Kim, Jong Min

    2016-01-01

    We investigate time-dependent inorganic ligand exchanging effect and photovoltaic performance of lead sulfide (PbS) nanocrystal films. With optimal processing time, volume shrinkage induced by residual oleic acid of the PbS colloidal quantum dot (CQD) was minimized and a crack-free film was obtained with improved flatness. Furthermore, sufficient surface passivation significantly increased the packing density by replacing from long oleic acid to a short iodide molecule. It thus facilities exciton dissociation via enhanced charge carrier transport in PbS CQD films, resulting in the improved power conversion efficiency from 3.39% to 6.62%. We also found that excess iodine ions on the PbS surface rather hinder high photovoltaic performance of the CQD solar cell.

  7. Inorganic-ligand exchanging time effect in PbS quantum dot solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byung-Sung; Hong, John; Hou, Bo; Cho, Yuljae; Sohn, Jung Inn, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk; Cha, SeungNam, E-mail: junginn.sohn@eng.ox.ac.uk, E-mail: seungnam.cha@eng.ox.ac.uk [Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ (United Kingdom); Kim, Jong Min [Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom)

    2016-08-08

    We investigate time-dependent inorganic ligand exchanging effect and photovoltaic performance of lead sulfide (PbS) nanocrystal films. With optimal processing time, volume shrinkage induced by residual oleic acid of the PbS colloidal quantum dot (CQD) was minimized and a crack-free film was obtained with improved flatness. Furthermore, sufficient surface passivation significantly increased the packing density by replacing from long oleic acid to a short iodide molecule. It thus facilities exciton dissociation via enhanced charge carrier transport in PbS CQD films, resulting in the improved power conversion efficiency from 3.39% to 6.62%. We also found that excess iodine ions on the PbS surface rather hinder high photovoltaic performance of the CQD solar cell.

  8. Unknown Aspects of Self-Assembly of PbS Microscale Superstructures

    Science.gov (United States)

    Querejeta-Fernández, Ana; Hernández-Garrido, Juan C.; Yang, Hengxi; Zhou, Yunlong; Varela, Aurea; Parras, Marina; Calvino-Gámez, José J.; González-Calbet, Jose M.; Green, Peter F.; Kotov, Nicholas A.

    2012-01-01

    A lot of interesting and sophisticated examples of nanoparticle (NP) self-assembly (SA) are known. From both fundamental and technological standpoints this field requires advancements in three principle directions: a) understanding the mechanism and driving forces of three-dimensional (3D) SA with both nano- and micro-levels of organization; b) understanding of disassembly/deconstruction processes; and c) finding synthetic methods of assembly into continuous superstructures without insulating barriers. From this perspective, we investigated the formation of well-known star-like PbS superstructures and found a number of previously unknown or overlooked aspects that can advance the knowledge of NP self-assembly in these three directions. The primary one is that the formation of large seemingly monocrystalline PbS superstructures with multiple levels of octahedral symmetry can be explained only by SA of small octahedral NPs. We found five distinct periods in the formation PbS hyperbranched stars: 1) nucleation of early PbS NPs with an average diameter of 31 nm; 2) assembly into 100–500 nm octahedral mesocrystals; 3) assembly into 1000–2500 nm hyperbranched stars; 4) assembly and ionic recrystallization into six-arm rods accompanied by disappearance of fine nanoscale structure; 5) deconstruction into rods and cubooctahedral NPs. The switches in assembly patterns between the periods occur due to variable dominance of pattern–determining forces that include vander Waals and electrostatic (charge-charge, dipole-dipole, and polarization) interactions. The superstructure deconstruction is triggered by chemical changes in the deep eutectic solvent (DES) used as the media. PbS superstructures can be excellent models for fundamental studies of nanoscale organization and SA manufacturing of (opto)electronics and energy harvesting devices which require organization of PbS components at multiple scales. PMID:22515512

  9. Designing heavy vehicles to be safer and more productive using PBS

    CSIR Research Space (South Africa)

    Kienhöfer, FW

    2013-07-01

    Full Text Available condition that the proposed vehicle’s safety is demonstrated either through physical testing or simulations. Such a PBS approach is currently being evaluated in South Africa. This paper summarises the productivity and safety increases of three PBS...

  10. Synthesis of star-shaped lead sulfide (PbS) nanomaterials and theirs gas-sensing properties

    Energy Technology Data Exchange (ETDEWEB)

    Song, Chengwen; Sun, Menghan; Yin, Yanyan; Xiao, Jingkun; Dong, Wei; Li, Chen; Zhang, Li, E-mail: chengwensong@dlmu.edu.cn [College of Environmental Science and Engineering, Dalian Maritime University, Dalian(China)

    2016-11-15

    Star-shaped PbS nanomaterials are synthesized by a hydrothermal method. Morphology and structure of the PbS nanomaterials are analyzed by SEM, HRTEM and XRD. Gas-sensing properties of the as-prepared PbS sensor are also systematically investigated. The results show star-shaped PbS nanostructure consists of four symmetric arms in the same plane and demonstrate good crystallinity. With the increase of ethanol concentration, the sensitivity of the PbS sensor significantly increases and demonstrates an almost linear relationship at the optimal operating temperature of 400 deg C. Moreover, the fast response-recovery towards ethanol is also observed, which indicates its great potential on ethanol detection. (author)

  11. Synthesis of star-shaped lead sulfide (PbS) nanomaterials and theirs gas-sensing properties

    International Nuclear Information System (INIS)

    Song, Chengwen; Sun, Menghan; Yin, Yanyan; Xiao, Jingkun; Dong, Wei; Li, Chen; Zhang, Li

    2016-01-01

    Star-shaped PbS nanomaterials are synthesized by a hydrothermal method. Morphology and structure of the PbS nanomaterials are analyzed by SEM, HRTEM and XRD. Gas-sensing properties of the as-prepared PbS sensor are also systematically investigated. The results show star-shaped PbS nanostructure consists of four symmetric arms in the same plane and demonstrate good crystallinity. With the increase of ethanol concentration, the sensitivity of the PbS sensor significantly increases and demonstrates an almost linear relationship at the optimal operating temperature of 400 deg C. Moreover, the fast response-recovery towards ethanol is also observed, which indicates its great potential on ethanol detection. (author)

  12. Optical properties of PbS thin films

    Energy Technology Data Exchange (ETDEWEB)

    Akhmedov, O. R., E-mail: orucahmedov@mail.ru; Guseinaliyev, M. G. [National Academy of Azerbaijan, Nakhichevan Branch (Azerbaijan); Abdullaev, N. A.; Abdullaev, N. M.; Babaev, S. S.; Kasumov, N. A. [National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan)

    2016-01-15

    The complex dielectric function of PbS thin films is studied by spectroscopic ellipsometry in the spectral range from 0.74 to 6.45 eV at a temperature of 293 K. The critical energies are determined to be E{sub 1} = 3.53 eV and E{sub 2} = 4.57 eV. For both energy regions, the best fit is attained at the critical point 2D (m = 0). In addition, the Raman spectra and the optical-absorption spectra of PbS thin films are studied. From the dependence of the quantity (αhν){sup 2} on the photon energy hν, the band gap is established at E{sub g} = 0.37 eV.

  13. Staying True to Our PBS Roots in a Changing World

    Science.gov (United States)

    Kincaid, Don

    2018-01-01

    The field of Positive Behavior Support (PBS) has grown and changed significantly in the past 25 years and should be expected to continue that trend for the next 25 years. These changes cannot always be predicted, but they can be managed by considering some current changes to the definition of PBS (Kincaid et al., 2016). This paper discussed how…

  14. Molecular characterization of Fagaceae species using inter-primer binding site (iPBS) markers.

    Science.gov (United States)

    Coutinho, João Paulo; Carvalho, Ana; Martín, Antonio; Lima-Brito, José

    2018-04-01

    Retrotransposons (RTNs) contribute for genome evolution, influencing its size and structure. We investigated the utility of the RTN-based markers inter-primer binding site (iPBS) for the molecular characterization of 25 Fagaceae species from genera Castanea, Fagus and Quercus. The assessment of genetic diversity, relationships and structure, as well as taxonomic classification of Fagaceae based on molecular data is important for definition of conservation, forestry management strategies and discrimination among natural hybrids and their parents since natural hybridization may increase with the climate changes. Here, iPBS primers designed by other authors were tested alone and combined. Some of them were discriminative, revealed polymorphism within and among taxa allowing the production of a total of 150 iPBS markers. In addition, several monomorphic iPBS markers were also amplified in each taxon. The UPGMA dendrogram based on the pooled iPBS data revealed 27% of genetic similarity among species. The individuals were clustered per genus and most of the oaks per infrageneric group corroborating the adopted taxonomy. Globally, the iPBS markers demonstrated suitability for DNA fingerprinting, determination of phylogenies and taxonomic discrimination in Fagaceae, and could constitute a useful and alternative tool for germplasm characterization, and for definition of conservation strategies and forestry management. Moreover, these markers would be useful for fingerprinting natural hybrids that share morphological similarities with their parents. Since iPBS markers could also enable insights about RTNs evolution, an eventual correlation among iPBS polymorphism, variability of RTN insertions and/or genome size in Fagaceae is discussed.

  15. γ-ray radiation effect on properties of straw powder/PBS composite

    International Nuclear Information System (INIS)

    Yang Mingcheng; Luo Yongquan; Liu Wentao; Zhu Jun; Guo Dongquan; Li Zhaopeng; Gen Feng; Qu Lingbo

    2013-01-01

    Background: In recent years, with decreasing global fossil resources and increasing 'white pollution', renewable and biodegradable materials attract more and more attentions. Poly (butylene succinate) (PBS) has good mechanical property, biodegradability and processing performance, which is the focus of hot topics in the study of biodegradable plastic materials, however, being soft and of high cost, it is still limited in application range. Purpose: In order to improve the mechanical and thermal properties, a series of wheat straw powder/PBS composites were prepared by melt extrusion, and then the 60 Co-y ray was directly utilized to irradiate the straw powder/PBS composite. Methods: The influence of TAIC (triallyl isocyanurate) radiation absorbed dose and radiation sensitizer on the mechanical property and thermal performance of straw powder/PBS composite was investigated, and the impact fracture surface morphology of the composite was observed by SEM (scanning electron microscope). Results: The tensile strength and flexural strength were enhanced with increasing radiation dosage, and then tend to be stable, the heat distortion temperature also increased but not significantly with increasing radiation dosage. The results show that when TAIC content is 2%, with straw powder/PBS composite irradiated by 30-kGy dose, the tensile strength and flexural strength are increased by 26% and 39.8%, respectively. Conclusion: The radiation modification of composite material has no effect on thermal stability, but do improve the tensile strength and flexural strength when up to 2% of TAIC is integrated and irradiated by certain dose. The interface cohesiveness between straw powder and PBS is strengthened after radiation. (authors)

  16. Evaluation of genetic diversity in open pollinated guava by iPBS primers

    International Nuclear Information System (INIS)

    Mehmood, A.; Jaskani, M.J.; Ahmad, S.; Ahmad, R.

    2013-01-01

    DNA markers are important tools for assessing genetic diversity and relationships among species, cultivars and breeding materials. Many horticultural species are lacking genomic information. DNA markers that do not require prior knowledge of DNA sequences are therefore appealing for horticultural research. A retrotransposon-based DNA marker system, iPBS (inter primer binding sites) developed from conserved primer binding sites within retrotransposons, was used to study the genetic variation and relationships in ornamental guava. PCR from 6 iPBS primers (dominant markers) produced a total of 113 bands (52.38-100% polymorphic) ranging from 150 bp to 3000 bp, and the mean PIC value for each primer ranging from 0.1245 to 0.3698. Molecular information generated from both iPBS was separately scored in a matrix for phylogenetic dendrogram construction. The phylogenetic dendrogram based on iPBS markers reflected morphologic classifications of the accessions that were studied. The iPBS PCR-based genome fingerprinting technology in this study is low-cost and provides another effective alternative in differentiation of accessions in guava (Psidium guajava Linn.) and related species or genera. (author)

  17. Controlled self-assembly of PbS nanoparticles into macrostar-like hierarchical structures

    International Nuclear Information System (INIS)

    Li, Guowei; Li, Changsheng; Tang, Hua; Cao, Kesheng; Chen, Juan

    2011-01-01

    Graphical abstract: The aggregation and rotation of nanoparticles to adopt parallel orientations in three dimensions was indirectly illustrated by TEM and HRTEM images. Highlights: → Macrostar-like PbS hierarchical structures was successfully synthesized by a simple hydrothermal method and mesostars were assembled from the PbS nanocube building blocks with edge lengths of about 100 nm. → Ostwald-ripening-assisted oriented attachment is believed to play a key role in the growth behavior of novel 3D structures. → Optical properties indicating few defects on the surface of the PbS structure and exhibit large blue-shifts compared to bulk PbS. -- Abstract: The synthesis of macrostar-like PbS hierarchical structures by a simple hydrothermal method at 180 o C for 24 h is proven successful with the assistance of a new surfactant called tetrabutylammonium bromide (TBAB). The as-obtained product is characterized by means of X-ray powder diffraction, field emission scanning electron microscopy, energy dispersive spectrometry, high resolution transmission electron microscopy, and selected area electron diffraction. The presence of TBAB and NaF plays an important role in the formation of PbS macrostructures. Ostwald-ripening-assisted oriented attachment is believed to play a key role in the growth behavior of novel 3D structures. As such, a possible self-assembly mechanism is proposed to explain the formation of the said structures. The present study aims to introduce new insights into understanding the formation process of such unique hierarchical superstructures.

  18. All-solution-processed PbS quantum dot solar modules

    Science.gov (United States)

    Jang, Jihoon; Shim, Hyung Cheoul; Ju, Yeonkyeong; Song, Jung Hoon; An, Hyejin; Yu, Jong-Su; Kwak, Sun-Woo; Lee, Taik-Min; Kim, Inyoung; Jeong, Sohee

    2015-05-01

    A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas.A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade

  19. Comparison of the co-gasification of sewage sludge and food wastes and cost-benefit analysis of gasification- and incineration-based waste treatment schemes.

    Science.gov (United States)

    You, Siming; Wang, Wei; Dai, Yanjun; Tong, Yen Wah; Wang, Chi-Hwa

    2016-10-01

    The compositions of food wastes and their co-gasification producer gas were compared with the existing data of sewage sludge. Results showed that food wastes are more favorable than sewage sludge for co-gasification based on residue generation and energy output. Two decentralized gasification-based schemes were proposed to dispose of the sewage sludge and food wastes in Singapore. Monte Carlo simulation-based cost-benefit analysis was conducted to compare the proposed schemes with the existing incineration-based scheme. It was found that the gasification-based schemes are financially superior to the incineration-based scheme based on the data of net present value (NPV), benefit-cost ratio (BCR), and internal rate of return (IRR). Sensitivity analysis was conducted to suggest effective measures to improve the economics of the schemes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. The Optimal Configuration Scheme of the Virtual Power Plant Considering Benefits and Risks of Investors

    Directory of Open Access Journals (Sweden)

    Jingmin Wang

    2017-07-01

    Full Text Available A virtual power plant (VPP is a special virtual unit that integrates various distributed energy resources (DERs distributed in the generation and consumption sides. The optimal configuration scheme of the VPP needs to break the geographical restrictions to make full use of DERs, considering the uncertainties. First, the components of the DERs and the structure of the VPP are briefly introduced. Next, the cubic exponential smoothing method is adopted to predict the VPP load requirement. Finally, the optimal configuration of the DER capacities inside the VPP is calculated by using portfolio theory and genetic algorithms (GA. The results show that the configuration scheme can optimize the DER capacities considering uncertainties, guaranteeing economic benefits of investors, and fully utilizing the DERs. Therefore, this paper provides a feasible reference for the optimal configuration scheme of the VPP from the perspective of investors.

  1. Predicting the benefit of binaural cue preservation in bilateral directional processing schemes for listeners with impaired hearing

    DEFF Research Database (Denmark)

    Brand, Thomas; Hauth, Christopher; Wagener, Kirsten C.

    2018-01-01

    Linked pairs of hearing aids offer various possibilities for directional processing providing adjustable trade-off between improving signal-to-noise ratio and preserving binaural listening. The benefit depends on the processing scheme, the acoustic scenario, and the listener’s ability to exploit...... fine structure. BSIM revealed a benefit due to binaural processing in well-performing listeners when processing provided low-frequency interaural timing cues....

  2. Graphene and PbS quantum dot hybrid vertical phototransistor

    Science.gov (United States)

    Song, Xiaoxian; Zhang, Yating; Zhang, Haiting; Yu, Yu; Cao, Mingxuan; Che, Yongli; Dai, Haitao; Yang, Junbo; Ding, Xin; Yao, Jianquan

    2017-04-01

    A field-effect phototransistor based on a graphene and lead sulfide quantum dot (PbS QD) hybrid in which PbS QDs are embedded in a graphene matrix has been fabricated with a vertical architecture through a solution process. The n-type Si/SiO2 substrate (gate), Au/Ag nanowire transparent source electrode, active layer and Au drain electrode are vertically stacked in the device, which has a downscaled channel length of 250 nm. Photoinduced electrons in the PbS QDs leap into the conduction band and fill in the trap states, while the photoinduced holes left in the valence band transfer to the graphene and form the photocurrent under biases from which the photoconductive gain is evaluated. The graphene/QD-based vertical phototransistor shows a photoresponsivity of 2 × 103 A W-1, and specific detectivity up to 7 × 1012 Jones under 808 nm laser illumination with a light irradiance of 12 mW cm-2. The solution-processed vertical phototransistor provides a new facile method for optoelectronic device applications.

  3. Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Firdaus, Yuliar; Van der Auweraer, Mark, E-mail: mark.vanderauweraer@chem.kuleuven.be [Laboratory of Photochemistry and Spectroscopy, Division of Molecular Imaging and Photonics, Chemistry Department, KULeuven, Celestijnenlaan 200F, 2404, B-3001 Leuven (Belgium); Vandenplas, Erwin; Gehlhaar, Robert; Cheyns, David [Imec vzw, Kapeldreef 75, B-3001 Leuven (Belgium); Justo, Yolanda; Hens, Zeger [Physical Chemistry Laboratory, Ghent University, Krijgslaan 281-S3, 9000 Gent (Belgium)

    2014-09-07

    Different approaches of surface modification of the quantum dots (QDs), namely, solution-phase (octylamine, octanethiol) and post-deposition (acetic acid, 1,4-benzenedithiol) ligand exchange were used in the fabrication of hybrid bulk heterojunction solar cell containing poly (3-hexylthiophene) (P3HT) and small (2.4 nm) PbS QDs. We show that replacing oleic acid by shorter chain ligands improves the figures of merit of the solar cells. This can possibly be attributed to a combination of a reduced thickness of the barrier for electron transfer and an optimized phase separation. The best results were obtained for post-deposition ligand exchange by 1,4-benzenedithiol, which improves the power conversion efficiency of solar cells based on a bulk heterojunction of lead sulfide (PbS) QDs and P3HT up to two orders of magnitude over previously reported hybrid cells based on a bulk heterojunction of P3HT:PbS QDs, where the QDs are capped by acetic acid ligands. The optimal performance was obtained for solar cells with 69 wt. % PbS QDs. Besides the ligand effects, the improvement was attributed to the formation of an energetically favorable bulk heterojunction with P3HT, when small size (2.4 nm) PbS QDs were used. Dark current density-voltage (J-V) measurements carried out on the device provided insight into the working mechanism: the comparison between the dark J-V characteristics of the bench mark system P3HT:PCBM and the P3HT:PbS blends allows us to conclude that a larger leakage current and a more efficient recombination are the major factors responsible for the larger losses in the hybrid system.

  4. Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots

    International Nuclear Information System (INIS)

    Firdaus, Yuliar; Van der Auweraer, Mark; Vandenplas, Erwin; Gehlhaar, Robert; Cheyns, David; Justo, Yolanda; Hens, Zeger

    2014-01-01

    Different approaches of surface modification of the quantum dots (QDs), namely, solution-phase (octylamine, octanethiol) and post-deposition (acetic acid, 1,4-benzenedithiol) ligand exchange were used in the fabrication of hybrid bulk heterojunction solar cell containing poly (3-hexylthiophene) (P3HT) and small (2.4 nm) PbS QDs. We show that replacing oleic acid by shorter chain ligands improves the figures of merit of the solar cells. This can possibly be attributed to a combination of a reduced thickness of the barrier for electron transfer and an optimized phase separation. The best results were obtained for post-deposition ligand exchange by 1,4-benzenedithiol, which improves the power conversion efficiency of solar cells based on a bulk heterojunction of lead sulfide (PbS) QDs and P3HT up to two orders of magnitude over previously reported hybrid cells based on a bulk heterojunction of P3HT:PbS QDs, where the QDs are capped by acetic acid ligands. The optimal performance was obtained for solar cells with 69 wt. % PbS QDs. Besides the ligand effects, the improvement was attributed to the formation of an energetically favorable bulk heterojunction with P3HT, when small size (2.4 nm) PbS QDs were used. Dark current density-voltage (J-V) measurements carried out on the device provided insight into the working mechanism: the comparison between the dark J-V characteristics of the bench mark system P3HT:PCBM and the P3HT:PbS blends allows us to conclude that a larger leakage current and a more efficient recombination are the major factors responsible for the larger losses in the hybrid system

  5. SU-E-T-266: Proton PBS Plan Design and Robustness Evaluation for Head and Neck Cancers

    International Nuclear Information System (INIS)

    Liang, X; Tang, S; Zhai, H; Kirk, M; Kalbasi, A; Lin, A; Ahn, P; Tochner, Z; McDonough, J; Both, S

    2014-01-01

    Purpose: To describe a newly designed proton pencil beam scanning (PBS) planning technique for radiotherapy of patients with bilateral oropharyngeal cancer, and to assess plan robustness. Methods: We treated 10 patients with proton PBS plans using 2 posterior oblique field (2F PBS) comprised of 80% single-field uniform dose (SFUD) and 20% intensity-modulated proton therapy (IMPT). All patients underwent weekly CT scans for verification. Using dosimetric indicators for both targets and organs at risk (OARs), we quantitatively compared initial plans and verification plans using student t-tests. We created a second proton PBS plan for each patient using 2 posterior oblique plus 1 anterior field comprised of 100% SFUD (3F PBS). We assessed plan robustness for both proton plan groups, as well as a photon volumetric modulated arc therapy (VMAT) plan group by comparing initial and verification plans. Results: The 2F PBS plans were not robust in target coverage. D98% for clinical target volume (CTV) degraded from 100% to 96% on average, with maximum change Δ D98% of −24%. Two patients were moved to photon VMAT treatment due to insufficient CTV coverage on verification plans. Plan robustness was especially weak in the low-anterior neck. The 3F PBS plans, however, demonstrated robust target coverage, which was comparable to the VMAT photon plan group. Doses to oral cavity were lower in the Proton PBS plans compared to photon VMAT plans due to no lower exit dose to the oral cavity. Conclusion: Proton PBS plans using 2 posterior oblique fields were not robust for CTV coverage, due to variable positioning of redundant soft tissue in the posterior neck. We designed 3-field proton PBS plans using an anterior field to avoid long heterogeneous paths in the low neck. These 3-field proton PBS plans had significantly improved plan robustness, and the robustness is comparable to VMAT photon plans

  6. Study of structural and optical properties of PbS thin films

    Science.gov (United States)

    Homraruen, T.; Sudswasd, Y.; Sorod, R.; Kayunkid, N.; Yindeesuk, W.

    2018-03-01

    This research aimed to synthesize lead sulfide (PbS) thin films on glass slides using the successive ion layer absorption and reaction (SILAR) method. We studied the optical properties and structure of PbS thin films by changing the number of dipping cycles and the concentration of precursor solution. The results of this experiment show that different conditions have a considerable influence on the thickness and absorbance of the films. When the number of dipping cycles and the concentration of the solution are increased, film thickness and absorbance tend to become higher. The xrays diffraction pattern showed all the diffraction peaks which confirmed the face center cubic and the structure of PbS had identified. Grain size computation was used to confirm how much these conditions could be affected.

  7. Na-A4 zeolites as host of PbS nanoparticles

    International Nuclear Information System (INIS)

    Flores A, M.; Perez S, R.; Aceves T, R.; Arizpe C, H.; Sotelo L, M.; Ramirez B, R.

    2006-01-01

    In this work we report the optical and structural properties of composite materials based on the semiconductor PbS enclosed in type A zeolite. The composite materials were obtained by chemical reaction in several steps of the zeolite in alkaline aqueous solutions containing Pb 2+ and S 2- ions successively. Three samples were prepared at temperatures of 40, 50 and 60 C during the chemical reaction with S 2- ions. The obtained materials were studied by x-ray diffraction, scanning and transmission electron microscopy, diffuse reflectance spectroscopy and photoluminescence. The experimental results show the formation of spherical-shaped PbS particles with nano metric size and cubic crystalline structure embedded in the zeolite matrix. The absorption spectra of the samples display a well defined absorption band at about 300 nm due to the PbS nanoparticles in the zeolite matrix. In addition, an absorption peak appears in the absorption spectra at about 400 nm assigned to exciton transitions. (Author)

  8. Synthesis and Characterization of Quantum Dots: A Case Study Using PbS

    Science.gov (United States)

    Pan, Yi; Li, Yue Ru; Zhao, Yu; Akins, Daniel L.

    2015-01-01

    A research project for senior undergraduates of chemistry has been developed to introduce syntheses of a series of monodispersed semiconductor PbS quantum dots (QDs) and their characterization methodologies. In this paper, we report the preparation of monodispersed semiconductor PbS QDs with sizes smaller than the exciton Bohr radius using a…

  9. Chemical bath deposited PbS thin films on ZnO nanowires for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Gertman, Ronen [Dept of Chemistry, Ben Gurion University of the Negev, Be' er Sheva 84105 (Israel); Ilse Katz Institute for Nanoscale Science and Technology, Ben Gurion University of the Negev, Be' er Sheva 84105 (Israel); Osherov, Anna; Golan, Yuval [Dept of Materials Engineering, Ben Gurion University of the Negev, Be' er Sheva 84105 (Israel); Ilse Katz Institute for Nanoscale Science and Technology, Ben Gurion University of the Negev, Be' er Sheva 84105 (Israel); Visoly-Fisher, Iris, E-mail: irisvf@bgu.ac.il [Ilse Katz Institute for Nanoscale Science and Technology, Ben Gurion University of the Negev, Be' er Sheva 84105 (Israel); Department of Solar Energy and Environmental Physics, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben Gurion University of the Negev, Sede Boqer Campus 84990 (Israel)

    2014-01-01

    Photovoltaic devices usually exploit mid-range band-gap semiconductors which absorb in the visible range of the solar spectrum. However, much energy is lost in the IR and near-IR range. We combined the advantages of small band-gap, bulk-like PbS deposited by facile, cheap and direct chemical bath deposition (CBD), with the good electronic properties of ZnO and the large surface area of nanowires, towards low cost photovoltaic devices utilizing IR and near-IR light. Surprisingly, CBD of PbS on ZnO, and particularly on ZnO nanowires, was not studied hitherto. Therefore, the mechanism of PbS growth by chemical bath deposition on ZnO nanowires was studied in details. A visible proof is shown for a growth mechanism starting from amorphous Pb(OH){sub 2} layer, that evolved into the ‘ion-by-ion’ growth mechanism. The growth mechanism and the resulting morphology at low temperatures were controlled by the thiourea concentration. The grain size affected the magnitude of the band-gap and was controlled by the deposition temperatures. Deposition above 40 °C resulted in bulk-like PbS with an optical band-gap of 0.4 eV. Methods were demonstrated for achieving complete PbS coverage of the complex ZnO NW architecture, a crucial requirement in optoelectronic devices to prevent shorts. Measurements of photocurrents under white and near-IR (784 nm) illumination showed that despite a 200 meV barrier for electron transfer at the PbS/ZnO interface, extraction of photo-electrons from PbS to the ZnO was feasible. The ability to harvest electrons from a narrow band-gap semiconductor deposited on a large surface-area electrode can advance the field towards high efficiency, low cost IR and near-IR sensors and third generation solar cells. - Highlights: • PbS was deposited on ZnO nanowires using chemical bath deposition. • At 50 °C the growth mechanism starts from an amorphous Pb(OH){sub 2} layer. • At 5 °C the growth mechanism of PbS can be controlled by thiourea concentrations

  10. High-contrast MacNeille-PBS-based LCOS projection systems

    Science.gov (United States)

    Chen, Jianmin; Robinson, Michael G.; Sharp, Gary D.

    2005-04-01

    Contrast limits are investigated for MacNeille PBS based LCOS projection systems that use retarder stack filters (RSF). The two contributing factors are considered separately; namely the color management system and the panel port. To enhance performance of the former, skew ray compensated RSFs are introduced. For the latter, a general methodology is presented to optimize contrast by compensating the LCOS panel. It is shown that the orientation of the LCOS panel and compensator, relative to the MacNeille PBS, is critical. The significant impact of AR coating performance on system contrast is also revealed. A high contrast architecture will be presented by way of example.

  11. Spectroscopic evidence of resonance energy transfer mechanism from PbS QDs to bulk silicon

    Directory of Open Access Journals (Sweden)

    Bernechea M.

    2013-06-01

    Full Text Available In this work, we study the efficiency of the resonance energy transfer from PbS quantum dots to bulk silicon. We present spectroscopic evidence that resonance energy transfer from PbS quantum dots to bulk silicon can be an efficient process for separation distances below 12 nm. Temperature measurements are also presented for PbS quantum dots deposited on glass and silicon with 5 nm and 20nm spacer thicknesses substrates. Our findings show that the resonance energy transfer efficiency remains constant over the 50K to 300K temperature range.

  12. Barriers to Co-Contribution in Superannuation: a Comparative Assessment of the Financial Benefits of Scheme Participation

    Directory of Open Access Journals (Sweden)

    Aaron Bruhn

    2013-09-01

    Full Text Available Voluntary superannuation contributions provide a means for individuals to top-up their savings in a tax advantaged environment. In order to encourage voluntary contributions the government instituted the cocontribution scheme in 2003. Under the existing scheme, within a given financial year the government contributes up to a maximum of $500 when an individual on a low income makes a voluntary contribution of up to $1,000. Despite the apparent financial attractiveness of the scheme, participation among eligible persons is low. Reasons may include competing expenditure needs leading to a lack of sufficient funds for contribution, lack of trust in the system given regular changes to superannuation policy, and behavioural reasons including a short-term rather than long-term focus, procrastination from uncertainty and fear of regret, and loss aversion. In this paper we investigate another possible reason for low participation, namely poor financial opportunity cost. While an immediate 50% investment return may appear to be a ‘no-brainer’, for eligible individuals or families with mortgages, scheme participation may in fact not be optimal. We investigate the relative benefit of scheme participation versus reducing a mortgage, and conclude that while participation is sensible for those with short remaining mortgage terms, for those with longer mortgage terms the decision to participate may not be preferred unless one assumes generous long-term superannuation investment returns, or unless scheme participation is intended year on year for long durations.

  13. Exploring synergistic benefits of Water-Food-Energy Nexus through multi-objective reservoir optimization schemes.

    Science.gov (United States)

    Uen, Tinn-Shuan; Chang, Fi-John; Zhou, Yanlai; Tsai, Wen-Ping

    2018-08-15

    This study proposed a holistic three-fold scheme that synergistically optimizes the benefits of the Water-Food-Energy (WFE) Nexus by integrating the short/long-term joint operation of a multi-objective reservoir with irrigation ponds in response to urbanization. The three-fold scheme was implemented step by step: (1) optimizing short-term (daily scale) reservoir operation for maximizing hydropower output and final reservoir storage during typhoon seasons; (2) simulating long-term (ten-day scale) water shortage rates in consideration of the availability of irrigation ponds for both agricultural and public sectors during non-typhoon seasons; and (3) promoting the synergistic benefits of the WFE Nexus in a year-round perspective by integrating the short-term optimization and long-term simulation of reservoir operations. The pivotal Shihmen Reservoir and 745 irrigation ponds located in Taoyuan City of Taiwan together with the surrounding urban areas formed the study case. The results indicated that the optimal short-term reservoir operation obtained from the non-dominated sorting genetic algorithm II (NSGA-II) could largely increase hydropower output but just slightly affected water supply. The simulation results of the reservoir coupled with irrigation ponds indicated that such joint operation could significantly reduce agricultural and public water shortage rates by 22.2% and 23.7% in average, respectively, as compared to those of reservoir operation excluding irrigation ponds. The results of year-round short/long-term joint operation showed that water shortage rates could be reduced by 10% at most, the food production rate could be increased by up to 47%, and the hydropower benefit could increase up to 9.33 million USD per year, respectively, in a wet year. Consequently, the proposed methodology could be a viable approach to promoting the synergistic benefits of the WFE Nexus, and the results provided unique insights for stakeholders and policymakers to pursue

  14. Influence of PbS nanoparticle polymer coating on their aggregation behavior and toxicity to the green algae Dunaliella salina

    Energy Technology Data Exchange (ETDEWEB)

    Zamani, Hajar [Department of Biology, Faculty of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Moradshahi, Ali, E-mail: moradshahi@susc.ac.ir [Department of Biology, Faculty of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Jahromi, Hamed Dehdashti; Sheikhi, Mohammad Hosein [Nanotechnology Research Institute, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of)

    2014-09-15

    Highlights: • Lead sulfide nanoparticles (PbS NPs) are toxic to D. salina. • Gum-Arabic coating alters the toxicity of PbS NPs. • Cell-NPs agglomerates and lipid peroxidation could explain the toxicity of PbS NPs. • Shading effect and dissolution do not seem to contribute to the toxicity of PbS NPs. • Particle–particle interaction was reduced by coating; therefore, PbS NPs were stabilized in the culture media. - Abstract: The potential hazards of nanoparticles (NPs) to the environment and to living organisms need to be considered for a safe development of nanotechnology. In the present study, the potential toxic effects of uncoated and gum Arabic-coated lead sulfide nanoparticles (GA-coated PbS NPs) on the growth, lipid peroxidation, reducing capacity and total carotenoid content of the hypersaline unicellular green algae Dunaliella salina were investigated. Coatings of PbS NPs with GA, as confirmed by Fourier transform infrared spectroscopy, reduced the toxicity of PbS NPs. Uncoated PbS NP toxicity to D. salina was attributed to higher algal cell-NP agglomerate formation, higher lipid peroxidation, lower content of total reducing substances and lower total carotenoid content. Low levels of Pb{sup 2+} in the growth culture media indicate that PbS NP dissolution does not occur in the culture. Also, the addition of 100 μM Pb{sup 2+} to the culture media had no significant (P > 0.05) effect on algal growth. The shading of light (shading effect) by PbS NPs, when simulated using activated charcoal, did not contribute to the overall toxic effect of PbS NPs which was evident by insignificant (P > 0.05) reduction in the growth and antioxidant capacity of the algae. When PbS NP aggregation in culture media (without algal cells) was followed for 60 min, uncoated form aggregated rapidly reaching aggregate sizes with hydrodynamic diameter of over 2500 nm within 60 min. Effective particle–particle interaction was reduced in the GA-coated NPs. Aggregates of about

  15. Influence of PbS nanoparticle polymer coating on their aggregation behavior and toxicity to the green algae Dunaliella salina

    International Nuclear Information System (INIS)

    Zamani, Hajar; Moradshahi, Ali; Jahromi, Hamed Dehdashti; Sheikhi, Mohammad Hosein

    2014-01-01

    Highlights: • Lead sulfide nanoparticles (PbS NPs) are toxic to D. salina. • Gum-Arabic coating alters the toxicity of PbS NPs. • Cell-NPs agglomerates and lipid peroxidation could explain the toxicity of PbS NPs. • Shading effect and dissolution do not seem to contribute to the toxicity of PbS NPs. • Particle–particle interaction was reduced by coating; therefore, PbS NPs were stabilized in the culture media. - Abstract: The potential hazards of nanoparticles (NPs) to the environment and to living organisms need to be considered for a safe development of nanotechnology. In the present study, the potential toxic effects of uncoated and gum Arabic-coated lead sulfide nanoparticles (GA-coated PbS NPs) on the growth, lipid peroxidation, reducing capacity and total carotenoid content of the hypersaline unicellular green algae Dunaliella salina were investigated. Coatings of PbS NPs with GA, as confirmed by Fourier transform infrared spectroscopy, reduced the toxicity of PbS NPs. Uncoated PbS NP toxicity to D. salina was attributed to higher algal cell-NP agglomerate formation, higher lipid peroxidation, lower content of total reducing substances and lower total carotenoid content. Low levels of Pb 2+ in the growth culture media indicate that PbS NP dissolution does not occur in the culture. Also, the addition of 100 μM Pb 2+ to the culture media had no significant (P > 0.05) effect on algal growth. The shading of light (shading effect) by PbS NPs, when simulated using activated charcoal, did not contribute to the overall toxic effect of PbS NPs which was evident by insignificant (P > 0.05) reduction in the growth and antioxidant capacity of the algae. When PbS NP aggregation in culture media (without algal cells) was followed for 60 min, uncoated form aggregated rapidly reaching aggregate sizes with hydrodynamic diameter of over 2500 nm within 60 min. Effective particle–particle interaction was reduced in the GA-coated NPs. Aggregates of about 440 nm

  16. Monitoring results of two PBS demonstration vehicles in the forestry industry in South Africa

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2010-03-01

    Full Text Available and manufactured to comply with the Level 2 safety standards of the Australian PBS system. This paper presents a summary of the monitoring data compiled during the first nine months of operation of the two PBS demonstration vehicles, which were commissioned...

  17. Co-sensitization of quantum dot sensitized solar cells composed of TiO2 nanocrystalline photoanode with CdS and PbS nanoparticles and effect of PbS on the performance of solar cell

    Directory of Open Access Journals (Sweden)

    Maziar Marandi

    2017-09-01

    Full Text Available In this research, CdS and PbS quantum dots were applied as the light sensitizers in TiO2 based nanostructured solar cells. The PbS quantum dots could absorb a wide range of the sunlight spectrum on earth due to their low bandgap energy. As a result, the cell sensitization is more effective by application of both CdS and PbS quantum dots sensitizers. The TiO2 nanocrystals were synthesized through a hydrothermal process and deposited on FTO glass substrates as the photoanode scaffold. Then PbS quantum dots were grown on the surface of this nanocrystalline layer by a successive ionic layer adsorption and reaction (SILAR method. The CdS quantum dots were over-grown in the next step through a similar deposition method. Finally this sensitized layer was applied as the photoelectrode of the corresponding quantum dot sensitized solar cells. The results demonstrated that the maximum efficiency was achieved for the cell with a photoanode made of co-sensitization through 2 and 6 cycles of PbS and CdS deposition, respectively. The photovoltaic parameters of this cell were measured as Jsc of 10.81 mA/cm2, Voc of 590 mv and energy conversion efficiency of 2.7+0.2%.

  18. Deposition and characteristics of PbS thin films by an in-situ solution chemical reaction process

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Junna; Ji, Huiming; Wang, Jian; Zheng, Xuerong; Lai, Junyun; Liu, Weiyan; Li, Tongfei [School of Materials Science and Engineering, Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, Tianjin University, Tianjin 300072 (China); Ma, Yuanliang; Li, Haiqin; Zhao, Suqin [College of Physics and Electronic Information Engineering, Qinghai University for Nationalities, Xining 810007 (China); Jin, Zhengguo, E-mail: zhgjin@tju.edu.cn [School of Materials Science and Engineering, Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, Tianjin University, Tianjin 300072 (China)

    2015-09-01

    Preferential oriented and uniform PbS thin films were deposited by a room temperature in-situ solution chemical reaction process, in which the lead nitrate as precursor in a form of thin solid films from lead precursor solution was used to react with ammonium sulfide ethanol solution. Influence of 1-butanol addition in the lead precursor solution, Pb:S molar ratios in the separate cationic and anionic solutions, deposition cycle numbers and annealing treatment in Ar atmosphere on structure, morphology, chemical composition and optical absorption properties of the deposited PbS films were investigated based on X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectrometer, atomic force microscopy, selected area electron diffraction, UV–vis, near infrared ray and fourier transform infrared spectroscopy measurements. The results showed that the deposited PbS thin films had a cubic structure and highly preferred orientation along with the plane (100). The deposition rate of single-layer was stable, about 30 nm in thickness per deposition cycle. - Highlights: • Time-efficiency synthetic method for the preparation of lead sulfide (PbS) films • Effect of 1-butanol addition into cationic precursor solution is discussed. • Growth rate of the PbS films is stable at about 30 nm per cycle.

  19. Preparation of nanostructured PbS thin films as sensing element for NO{sub 2} gas

    Energy Technology Data Exchange (ETDEWEB)

    Kaci, S., E-mail: k_samira05@yahoo.fr [Centre de Recherche en Technologie des Semi-conducteurs pour l’Energétique (CRTSE) Division Couches Minces et Interfaces, 02 Bd Frantz Fanon, B.P. 140, 7 Merveilles, 16038 Algiers (Algeria); Keffous, A.; Hakoum, S. [Centre de Recherche en Technologie des Semi-conducteurs pour l’Energétique (CRTSE) Division Couches Minces et Interfaces, 02 Bd Frantz Fanon, B.P. 140, 7 Merveilles, 16038 Algiers (Algeria); Trari, M. [Université des Sciences et Technologies Houari Boumediene (USTHB), Laboratoire de Stockage et de Valorisation des Eneriges Renouvelables, Faculté de Chimie, BP 32, EL Alia, 16111 Bab Ezzouar, Algiers (Algeria); Mansri, O.; Menari, H. [Centre de Recherche en Technologie des Semi-conducteurs pour l’Energétique (CRTSE) Division Couches Minces et Interfaces, 02 Bd Frantz Fanon, B.P. 140, 7 Merveilles, 16038 Algiers (Algeria)

    2014-06-01

    In this work, we demonstrate that semiconducting films of A{sub IV}B{sub VI} compounds, in particular, of nanostructured lead sulfide (PbS) which prepared by chemical bath deposition (CBD), can be used as a sensing element for nitrogen dioxide (NO{sub 2}) gas. The CBD method is versatile, simple in implementation and gives homogeneous semiconductor structures. We have prepared PbS nanocrystalline thin film at different reaction baths and temperatures. In the course of deposition, variable amounts of additives, such as organic substances among them, were introduced into the baths. The energy dispersive analysis (EDX) confirms the chemical composition of PbS films. A current–voltage (I–V) characterization of Pd/nc-PbS/a-SiC:H pSi(100)/Al Schottky diode structures were studied in the presence of NO{sub 2} gas. The gas sensing behavior showed that the synthesized PbS nanocrystalline thin films were influenced by NO{sub 2} gas at room temperature. The results can be used for developing an experimental sensing element based on chemically deposited nanostructured PbS films which can be applicable in gas sensors.

  20. Enhancement of Electron Transfer Efficiency in Solar Cells Based on PbS QD/N719 Dye Cosensitizers

    Directory of Open Access Journals (Sweden)

    Yanyan Gao

    2012-01-01

    Full Text Available Cosensitized solar cells (CSSCs have recently become an active subject in the field of sensitized solar cells (SSCs due to their increasing electronic utilization. However, because of the dye molecules, layer must be single, dye-SSCs cannot be co-sensitized with two different dyes to form two different molecules layer. But it is possible to be cosensitized with quantum dots (QDs and dyes. Here we designed novel photoanode architecture, namely, PbS QDs and N719 dyes are used as co-sensitizers of the TiO2 mesoporous film. The experimental result shows that PbS QDs/N719 dyes co-sensitized structure can make PbS QDs and N719 dyes mutual improvement. Taking the advantage of PbS not only achieved higher transfer efficiency of photo-excited electron, but also achieved obviously wider range and higher intensity of absorption. The PbS QDs which have been deposited on the TiO2 film was coated by N719 dyes, which can effectively prevent PbS QDs from corroding by I-/I3-electrolyte and light. As we expected, the solar energy-conversion efficiency which is showed by CSSCs fabricated following these photoanodes is relatively higher than the PbS QDs or N719 dyes, single-sensitized solar cells under the illumination of one sun.

  1. 77 FR 40358 - Federal Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings...

    Science.gov (United States)

    2012-07-09

    ... Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings: Correction AGENCY: Public Buildings Service (PBS), General Services Administration (GSA). ACTION: Notice of a bulletin..., 2012, a bulletin announcing the designation and redesignation of three Federal buildings. Inadvertently...

  2. Spanish adaptation of the Participatory Behaviors Scale (PBS

    Directory of Open Access Journals (Sweden)

    Alejandro Magallares

    2016-04-01

    Full Text Available The aim of this study was to adapt the Participatory Behaviors Scale (PBS and validate the results for use among the Spanish population. Using snowball sampling methodology, 501 individuals from all areas of Spain were selected to participate in the study. The Participatory Behaviors Scale (PBS and questionnaires that measure a sense of community, belief in a just world and Machiavellianism were used to analyze the criterion validity of the adapted scale. A confirmatory factor analysis indicated that the items on the questionnaire fit a second-order model with four factors, which corresponded to the four dimensions proposed by the original authors, namely, disengagement, civil participation, formal political participation and activism. Additionally, it has been found that the scale is related to a sense of community, belief in a just world and Machiavellianism. In light of these results, we concluded that the questionnaire is methodologically valid and can be used by the scientific community to measure participatory behavior.

  3. Should Governments engage health insurance intermediaries? A comparison of benefits with and without insurance intermediary in a large tax funded community health insurance scheme in the Indian state of Andhra Pradesh.

    Science.gov (United States)

    Nagulapalli, Srikant; Rokkam, Sudarsana Rao

    2015-09-10

    A peculiar phenomenon of engaging insurance intermediaries for government funded health insurance schemes for the poor, not usually found globally, is gaining ground in India. Rajiv Aarogyasri Scheme launched in the Indian state of Andhra Pradesh, is first largest tax funded community health insurance scheme in the country covering more than 20 million poor families. Aarogyasri Health Care Trust (trust), the scheme administrator, transfers funds to hospitals through two routes one, directly and the other through an insurance intermediary. The objective of this paper is to find out if engaging an insurance intermediary has any effect on cost efficiency of the insurance scheme. We used payment data of RAS for the period 2007-12, to find out the influence of insurance intermediary on the two variables, benefit cost ratio defined as benefit payment divided by premium payment, and claim denial ratio defined as benefit payment divided by treatment cost. Relationship between scheme expenditure and number of beds empanelled under the scheme is examined. OLS regression is used to perform all analyses. We found that adding an additional layer of insurance intermediary between the trust and hospitals reduced the benefit cost ratio under the scheme by 12.2% (p-value = 0.06). Every addition of 100 beds under the scheme increases the scheme payments by US$ 0.75 million (p-value insurance and trust modes narrowed down from 2.84% in government hospitals to 0.41% in private hospitals (p-value insurance intermediary has the twin effects of reduction in benefit payments to beneficiaries, and chocking fund flow to government hospitals. The idea of engaging insurance intermediary should be abandoned.

  4. A methodology for assessment of road structures for the PBS pilot project in South Africa

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2016-11-01

    Full Text Available This paper describes the methodology that is being used for the performance assessment of PBS vehicles in terms of road structures as part of the PBS pilot project in South Africa. The assessment approach has evolved from the standard “bridge...

  5. PbS Thin Films for Photovoltaic Applications Obtained by Non-Traditional Chemical Bath Deposition

    Directory of Open Access Journals (Sweden)

    Pérez-García Claudia Elena

    2015-01-01

    Full Text Available To optimize cost-efficiency relation for thin film solar cells, we explore the recently developed versions of chemical deposition of semiconductor films, together with classic CBD (Chemical Bath Deposition: SILAR (Successive Ionic Layer Adsorption and Reaction and PCBD (Photo Chemical Bath Deposition, all of them ammonia-free and ecologically friendly. The films of CdS and PbS were made, and experimental solar cells with CdS window layer and PbS absorber elaborated. We found that band gap of PbS films can be monitored by deposition process due to porosity-induced quantum confinement which depends on the parameters of the process. We expect that the techniques employed can be successfully used for production of optoelectronic devices.

  6. Effects of Hydroxylation on PbS Quantum Dot Sensitized TiO2 Nanotube Array Photoelectrodes

    International Nuclear Information System (INIS)

    Liu, Zhongqing; Wang, Bin; Wu, Jianchun; Dong, Qiang; Zhang, Xiaoming; Xu, He

    2016-01-01

    ABSTRACT: The contact state at the heterojunction interfaces greatly influences the interfacial kinetics of the photoinduced charge carriers. In this study, we used a facile NaOH pretreatment to replenish the hydroxyl groups lost during the heat treatment for crystallization of TiO 2 nanotube arrays (TNAs) prepared via anodic oxidization. By reacting the carboxylic acid groups of thioglycolic acid (TGA) with the TiO 2 surface hydroxyl groups, TGA molecules were covalently linked to the TiO 2 surface and then PbS quantum dots (QDs) were anchored onto the TNAs via the successive ionic layer adsorption and reaction (SILAR) method. The sample microstructure and photoelectrochemical properties were analyzed with X-ray diffraction (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM),current–voltage characteristics (J–V), electrochemical impedance spectroscopy (EIS), transient photovoltage plots and Mott-Schottky curves. The contact state and electrostatic potential distribution between TiO 2 {1 0 1} and PbS {1 1 1} planes were estimated by using first principle simulation. It was found that the NaOH pretreatment could enhance the crystallization degree of PbS QDs, decrease the crystal face mismatch, dangling bond density and the interfacial resistance between PbS QDs and TiO 2 , and accelerate the interfacial separation and transfer of photoinduced charge carriers. The first principle calculations demonstrated that the PbS QDs and TiO 2 interfacial contact was strengthened, and the built-in electric field was induced from TiO 2 {1 0 1} towards PbS {1 1 1}. These combined effects apparently improved the device photoelectrochemical performance. Compared to the sample without pretreatment, the specimen pretreated with NaOH demonstrated 19.96% and 29.93% increases in peak photoconversion efficiency after five and ten cycles of SILAR deposition, respectively.

  7. Facile preparation of PbS nanostructures and PbS/f-CNT nanocomposites using xanthate as sulfur source: Thermal and optical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Golabi, Parisa; Akbarzadeh, Raziyeh; Dehghani, Hossein, E-mail: dehghani@kashanu.ac.ir

    2015-10-25

    PbS nanostructures with different morphologies were fabricated using a new sulfur source through a facile and low cost hydro(solvo)thermal method. The influence of different reaction factors such as sulfur source, temperature, reactant, solvent and surfactant on the size and morphology of the obtained PbS particles were investigated. Beside, a simple hydrothermal process at low temperature (60 °C) for little time (4 h), has been used for preparation of PbS nanoparticles (NPs)/functionalized multi wall carbon nanotubes (f-MWCNTs) nanocomposite. The as-prepared nanocomposite possesses excellent thermal and optical properties. Thermal stability increases by depositing PbS nanoparticles on the surface of CNT. The structure, morphology, thermal and optical properties of the as-prepared nanocompounds were studied by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Scanning electron microscope (SEM), Energy-dispersive X-ray spectroscopy, Thermogravimetric analysis (TGA), Pl spectra and UV–Vis absorption spectra. Photoluminescence spectra of PbS NPs and nanocomposite are consist of two emission peaks which centered at around 402 and 423 nm, when excited at 350 nm. It was noteworthy that the blue luminescence intensity over PbS/f-CNT nanocomposite is very lower than that of pure PbS NPs. Remarkable blue-shift from bulk material was observed on the PbS nanoparticles using UV–Vis spectrum. Furthermore, possible growth mechanism of PbS nanostructures is presented. - Graphical abstract: PbS nanostructures with different morphologies were fabricated using xanthate as sulfide source. Also, PbS/f-CNT nanocomposites were synthesized by simple hydrothermal process at low temperature (60 °C) for little time (4 h). - Highlights: • Sodium tert-butyl xanthate was used as sulfur source for synthesis of PbS. • Pb(CH{sub 3}COO){sub 2}·3H{sub 2}O salt was used for synthesis of PbS. • PbS/CNT nanocomposite was synthesized in deionized water for 4 h at 60

  8. Tunneling effect on double potential barriers GaAs and PbS

    Science.gov (United States)

    Prastowo, S. H. B.; Supriadi, B.; Ridlo, Z. R.; Prihandono, T.

    2018-04-01

    A simple model of transport phenomenon tunnelling effect through double barrier structure was developed. In this research we concentrate on the variation of electron energy which entering double potential barriers to transmission coefficient. The barriers using semiconductor materials GaAs (Galium Arsenide) with band-gap energy 1.424 eV, distance of lattice 0.565 nm, and PbS (Lead Sulphide) with band gap energy 0.41 eV distance of lattice is 18 nm. The Analysisof tunnelling effect on double potentials GaAs and PbS using Schrodinger’s equation, continuity, and matrix propagation to get transmission coefficient. The maximum energy of electron that we use is 1.0 eV, and observable from 0.0025 eV- 1.0 eV. The shows the highest transmission coefficient is0.9982 from electron energy 0.5123eV means electron can pass the barriers with probability 99.82%. Semiconductor from materials GaAs and PbS is one of selected material to design semiconductor device because of transmission coefficient directly proportional to bias the voltage of semiconductor device. Application of the theoretical analysis of resonant tunnelling effect on double barriers was used to design and develop new structure and combination of materials for semiconductor device (diode, transistor, and integrated circuit).

  9. B1-B2 phase transition mechanism and pathway of PbS under pressure

    Science.gov (United States)

    Adeleke, Adebayo A.; Yao, Yansun

    2018-03-01

    Experimental studies at finite Pressure-Temperature (P-T) conditions and a theoretical study at 0 K of the phase transition in lead sulphide (PbS) have been inconclusive. Many studies that have been done to understand structural transformation in PbS can broadly be classified into two main ideological streams—one with Pnma and another with Cmcm orthorhombic intermediate phase. To foster better understanding of this phenomenon, we present the result of the first-principles study of phase transition in PbS at finite temperature. We employed the particle swarm-intelligence optimization algorithm for the 0 K structure search and first-principles metadynamics simulations to study the phase transition pathway of PbS from the ambient pressure, 0 K Fm-3m structure to the high-pressure Pm-3m phase under experimentally achievable P-T conditions. Significantly, our calculation shows that both streams are achievable under specific P-T conditions. We further uncover new tetragonal and monoclinic structures of PbS with space group P21/c and I41/amd, respectively. We propose the P21/c and I41/amd as a precursor phase to the Pnma and Cmcm phases, respectively. We investigated the stability of the new structures and found them to be dynamically stable at their stability pressure range. Electronic structure calculations reveal that both P21/c and I41/amd phases are semiconducting with direct and indirect bandgap energies of 0.69(5) eV and 0.97(3) eV, respectively. In general, both P21/c and I41/amd phases were found to be energetically competitive with their respective orthorhombic successors.

  10. Overcoming the Cut-Off Charge Transfer Bandgaps at the PbS Quantum Dot Interface

    KAUST Repository

    El-Ballouli, Ala'a O.

    2015-11-17

    Light harvesting from large size of semiconductor PbS quantum dots (QDs) with a bandgap of less than 1 eV is one of the greatest challenges precluding the development of PbS QD-based solar cells because the interfacial charge transfer (CT) from such QDs to the most commonly used electron acceptor materials is very inefficient, if it occurs at all. Thus, an alternative electron-accepting unit with a new driving force for CT is urgently needed to harvest the light from large-sized PbS QDs. Here, a cationic porphyrin is utilized as a new electron acceptor unit with unique features that bring the donor–acceptor components into close molecular proximity, allowing ultrafast and efficient electron transfer for QDs of all sizes, as inferred from the drastic photoluminescence quenching and the ultrafast formation of the porphyrin anionic species. The time-resolved results clearly demonstrate the possibility of modulating the electron transfer process between PbS QDs and porphyrin moieties not only by the size quantization effect but also by the interfacial electrostatic interaction between the positively charged porphyrin and the negatively charged QDs. This approach provides a new pathway for engineering QD-based solar cells that make the best use of the diverse photons making up the Sun\\'s broad irradiance spectrum.

  11. Overcoming the Cut-Off Charge Transfer Bandgaps at the PbS Quantum Dot Interface

    KAUST Repository

    El-Ballouli, Ala'a O.; Alarousu, Erkki; Kirmani, Ahmad R.; Amassian, Aram; Bakr, Osman; Mohammed, Omar F.

    2015-01-01

    Light harvesting from large size of semiconductor PbS quantum dots (QDs) with a bandgap of less than 1 eV is one of the greatest challenges precluding the development of PbS QD-based solar cells because the interfacial charge transfer (CT) from such QDs to the most commonly used electron acceptor materials is very inefficient, if it occurs at all. Thus, an alternative electron-accepting unit with a new driving force for CT is urgently needed to harvest the light from large-sized PbS QDs. Here, a cationic porphyrin is utilized as a new electron acceptor unit with unique features that bring the donor–acceptor components into close molecular proximity, allowing ultrafast and efficient electron transfer for QDs of all sizes, as inferred from the drastic photoluminescence quenching and the ultrafast formation of the porphyrin anionic species. The time-resolved results clearly demonstrate the possibility of modulating the electron transfer process between PbS QDs and porphyrin moieties not only by the size quantization effect but also by the interfacial electrostatic interaction between the positively charged porphyrin and the negatively charged QDs. This approach provides a new pathway for engineering QD-based solar cells that make the best use of the diverse photons making up the Sun's broad irradiance spectrum.

  12. Deposition of Cu-doped PbS thin films with low resistivity using DC sputtering

    Science.gov (United States)

    Soetedjo, Hariyadi; Siswanto, Bambang; Aziz, Ihwanul; Sudjatmoko

    2018-03-01

    Investigation of the electrical resistivity of Cu-doped PbS thin films has been carried out. The films were prepared using a DC sputtering technique. The doping was achieved by introducing the Cu dopant plate material directly on the surface of the PbS sputtering target plate. SEM-EDX data shows the Cu concentration in the PbS film to be proportional to the Cu plate diameter. The XRD pattern indicates the film is in crystalline cubic form. The Hall effect measurement shows that Cu doping yields an increase in the carrier concentration to 3.55 × 1019 cm-3 and a significant decrease in electrical resistivity. The lowest resistivity obtained was 0.13 Ωcm for a Cu concentration of 18.5%. Preferential orientation of (1 1 1) and (2 0 0) occurs during deposition.

  13. Monitoring results of PBS vehicles in South Africa in terms of productivity, safety and road wear performance

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2013-07-01

    Full Text Available As part of a Performance-Based Standards (PBS) research programme for heavy vehicles in South Africa, a need was identified to design, manufacture and operate a number of PBS or Smart Truck demonstration vehicles in order to gain practical...

  14. Photoluminescence properties of powder and pulsed laser-deposited PbS nanoparticles in SiO2

    International Nuclear Information System (INIS)

    Dhlamini, M.S.; Terblans, J.J.; Ntwaeaborwa, O.M.; Ngaruiya, J.M.; Hillie, K.T.; Botha, J.R.; Swart, H.C.

    2008-01-01

    Thin films of lead sulfide (PbS) nanoparticles embedded in an amorphous silica (SiO 2 ) host were grown on Si(1 0 0) substrates at different temperatures by the pulsed laser deposition (PLD) technique. Surface morphology and photoluminescence (PL) properties of samples were analyzed with scanning electron microscopy (SEM) and a 458 nm Ar + laser, respectively. The PL data show a blue-shift from the normal emission at ∼3200 nm in PbS bulk to ∼560-700 nm in nanoparticulate PbS powders and thin films. Furthermore, the PL emission of the films was red-shifted from that of the powders at ∼560 to ∼660 nm. The blue-shifting of the emission wavelengths from 3200 to ∼560-700 nm is attributed to quantum confinement of charge carriers in the restricted volume of nanoparticles, while the red-shift between powders and thin-film PbS nanoparticles is speculated to be due to an increase in the defect concentration. The red-shift increased slightly with an increase in deposition temperature, which suggests that there has been a relative growth in particle sizes during the PLD of the films at higher temperatures. Generally, the PL emission of the powders was more intense than that of the films, although the intensity of some of the films was improved marginally by post-deposition annealing at 400 deg. C. This paper compares the PL properties of powder and pulsed laser-deposited thin films of PbS nanoparticles and the effects of deposition temperatures

  15. A photodiode based on PbS nanocrystallites for FYTRONIX solar panel automatic tracking controller

    Science.gov (United States)

    Wageh, S.; Farooq, W. A.; Tataroğlu, A.; Dere, A.; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Yakuphanoglu, F.

    2017-12-01

    The structural, optical and photoelectrical properties of the fabricated Al/PbS/p-Si/Al photodiode based on PbS nanocrystallites were investigated. The PbS nanocrystallites were characterized by X-ray diffraction (XRD), UV-VIS-NIR, Infrared and Raman spectroscopy. The XRD diffraction peaks show that the prepared PbS nanostructure is in high crystalline state. Various electrical parameters of the prepared photodiode were analyzed from the electrical characteristics based on I-V and C-V-G. The photodiode has a high rectification ratio of 5.85×104 at dark and ±4 V. Moreover, The photocurrent results indicate a strong photovoltaic behavior. The frequency dependence of capacitance and conductance characteristics was attributed to depletion region behavior of the photodiode. The diode was used to control solar panel power automatic tracking controller in dual axis. The fabricated photodiode works as a photosensor to control Solar tracking systems.

  16. WE-E-BRB-03: Implementation of PBS Proton Therapy Treatment for Free Breathing Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Li, H. [UT MD Anderson Cancer Center (United States)

    2016-06-15

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed. Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of Pennsylvania and

  17. WE-E-BRB-02: Implementation of Pencil Beam Scanning (PBS) Proton Therapy Treatment for Liver Patient

    Energy Technology Data Exchange (ETDEWEB)

    Lin, L. [University of Pennsylvania (United States)

    2016-06-15

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed. Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of Pennsylvania and

  18. WE-E-BRB-03: Implementation of PBS Proton Therapy Treatment for Free Breathing Lung Cancer Patients

    International Nuclear Information System (INIS)

    Li, H.

    2016-01-01

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed. Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of Pennsylvania and

  19. WE-E-BRB-02: Implementation of Pencil Beam Scanning (PBS) Proton Therapy Treatment for Liver Patient

    International Nuclear Information System (INIS)

    Lin, L.

    2016-01-01

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed. Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of Pennsylvania and

  20. Deposition of Cu-doped PbS thin films with low resistivity using DC sputtering

    Directory of Open Access Journals (Sweden)

    Hariyadi Soetedjo

    2018-03-01

    Full Text Available Investigation of the electrical resistivity of Cu-doped PbS thin films has been carried out. The films were prepared using a DC sputtering technique. The doping was achieved by introducing the Cu dopant plate material directly on the surface of the PbS sputtering target plate. SEM-EDX data shows the Cu concentration in the PbS film to be proportional to the Cu plate diameter. The XRD pattern indicates the film is in crystalline cubic form. The Hall effect measurement shows that Cu doping yields an increase in the carrier concentration to 3.55 × 1019 cm−3 and a significant decrease in electrical resistivity. The lowest resistivity obtained was 0.13 Ωcm for a Cu concentration of 18.5%. Preferential orientation of (1 1 1 and (2 0 0 occurs during deposition. Keywords: Thin films, Lead sulfide, Sputtering, Resistivity, Semiconductor, Infrared

  1. Visit to general practitioners as a proxy for accessing chronic benefits by members of medical schemes, South Africa

    Directory of Open Access Journals (Sweden)

    Mncedisi M. Willie

    2012-10-01

    Full Text Available Background: Prescribed Minimum Benefits is a list of conditions that all medical schemes need to cover in full, and includes a select of chronic conditions. Chronic conditions affect people’s lifestyles and require ongoing management over a period of years for long-term survival. Objectives: This study examined the association between prevalence of selected chronic diseases and health service use, in particular visits to general practitioners (GPs by medical scheme members. Method: This was a retrospective study on medical schemes data. The median imputation method was employed to deal with missing and unreported chronic diseases prevalence. Multivariate logistic regression analysis was employed to assess effects of chronic disease prevalence, age stratum and scheme size on GP visits per annum. Results: The study showed that prevalence of asthma was significantly associated with more than three GP visits (OR = 1.081; 95% CI = 1.008–1.159, as was prevalence of type 2 diabetes (OR = 1.087; 95% CI = 1.027–1.152, whilst prevalence of hyperlipidaemia (OR = 0.92; 95% CI = 0.875–0.97 was more likely to be associated with less than three GP visits. Prevalence of hypertension was associated with more than three GP visits per year (OR = 1.132; 95% CI = 1.017–1.26. Conclusion: This study shows that scheme size, prevalence of chronic diseases such as asthma, type 2 diabetes, hyperlipidaemia and hypertension are related to GP visits. GPs and managed care programmes employed by schemes should give special attention to certain disease states with high prevalence rates in an effort to better manage them.

  2. Spin-coating deposition of PbS and CdS thin films for solar cell application

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Jayesh; Mighri, Frej [Laval University, CREPEC, Department of Chemical Engineering, Quebec, QC (Canada); Ajji, Abdellah [Ecole Polytechnique, CREPEC, Chemical Engineering Department, Montreal, QC (Canada); Tiwari, Devendra; Chaudhuri, Tapas K. [Charotar University of Science and Technology (CHARUSAT), Dr. K.C. Patel Research and Development Centre, Anand District, Gujarat (India)

    2014-12-15

    In this work, we describe a simple spin-coating deposition technique for lead sulphide (PbS) and cadmium sulphide (CdS) films from a methanolic metal-thiourea complex. The characterization of the films by X-ray diffraction and X-ray photoelectron spectroscopy techniques revealed that pure cubic phase PbS and CdS layers were formed via this method. As shown by atomic force microscopy and scanning electron microscopy results, both films were homogeneous and presented a smooth surface. Optical properties showed that the energy band gap of PbS and CdS films were around 1.65 and 2.5 eV, respectively. The PbS film is p-type in nature with an electrical conductivity of around 0.8 S/cm. The hole concentration and mobility were 2.35 x 10{sup 18} cm{sup -3} and 2.16 x 10{sup -3} cm{sup 2}/V/s, respectively, as determined from Hall measurement. Both films were used to develop a thin film solar cell device of graphite/PbS/CdS/ITO/glass. Device characterization showed the power conversion efficiency of around 0.24 %. The corresponding open circuit voltage, short circuit current and fill factor were 0.570 V, 1.32 mA/cm{sup 2} and 0.32, respectively. (orig.)

  3. Initiative to introduce a performance-based standards (PBS) approach for heavy vehicle design and operations in South Africa

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2008-05-01

    Full Text Available The introduction of PBS for heavy vehicles in South Africa was first identified in the National Overload Control Strategy as a potential concession of a proposed Self-regulation initiative. In August 2004 a PBS committee was established...

  4. Luminescence and transient lifetime studies for energy transfer of PbS QD films

    Science.gov (United States)

    Wang, Joanna S.; Ullrich, Bruno; Dass, Chandriker K.; Das, Anirban; Wai, Chien M.; Brown, Gail J.; Hendrickson, Joshua R.

    2017-08-01

    Quantum confined semiconductor materials in colloidal form have drawn great attention in scientific communities due to the size-tunability, which controls their optical properties. PbS quantum dots (QDs) are exciting candidates for quantum optics, particularly due to the control of the QD sizes during the synthetic process enabling the realization of precisely tunable emission properties in the near-infrared region. Differently sized pairs of PbS QDs were deposited onto glass substrates to form thin films using supercritical CO2 (sc-CO2) deposition and solvent deposition methods (SDM). The fluorescence and photoluminescence (PL) spectra obtained from these closely packed films prepared by the sc-CO2 method reveal effective Förster resonance energy transfer (FRET) between two different sized dots, while the films composed of three different QD sizes show an even more effective FRET from the smallest to the largest ones. Energy transfer can be observed more directly by temporally resolved PL decay of mixed dots. By means of transient lifetime measurements, a mixed PbS film with 3.1 and 4.7 nm QDs was studied for FRET by time correlated single photon counting. The PL peak of the 3.1 nm QDs is quenched with respect to the emission of the 4.7 nm QDs and decays faster, and the best fit for the lifetime (decay constant)-1 is a biexponential decay mode. The long wavelength decay (4.7 nm QDs) is best fit by a mono-exponential equation. More theoretical and experimental work is required for a thorough understanding of the radiative lifetimes of PbS QDs in mixed QD systems.

  5. Photoelectron emission as a tool to assess dose of electron radiation received by ZrO2:PbS films

    International Nuclear Information System (INIS)

    Krumpane, Diana; Dekhtyar, Yury; Surkova, Indra; Romanova, Marina

    2013-01-01

    PbS nano dots embedded in ZrO 2 thin film matrix (ZrO 2 :PbS films) were studied for application in nanodosimetry of electron radiation used in radiation therapy. ZrO 2 :PbS films were irradiated with 9 MeV electron radiation with doses 3, 7 and 10 Gy using medical linear accelerator. Detection of the dosimetric signal was made by measuring and comparing photoelectron emission current from ZrO 2 :PbS films before and after irradiation. It was found that electron radiation decreased intensity of photoemission current from the films. Derivatives of the photoemission spectra were calculated and maximums at photon energies 5.65 and 5.75 eV were observed. Amplitude of these maximums decreased after irradiation with electrons. Good linear correlation was found between the relative decrease of the intensity of these maximums and dose of electron radiation. Observed changes in photoemission spectra from ZrO 2 :PbS films under influence of electron radiation suggested that the films may be considered to be effective material for electron radiation dosimetry. Photoelectron emission is a tool that allows to read the signal from such dosimeter. (authors)

  6. iPBS: a universal method for DNA fingerprinting and retrotransposon isolation.

    Science.gov (United States)

    Kalendar, Ruslan; Antonius, Kristiina; Smýkal, Petr; Schulman, Alan H

    2010-11-01

    Molecular markers are essential in plant and animal breeding and biodiversity applications, in human forensics, and for map-based cloning of genes. The long terminal repeat (LTR) retrotransposons are well suited as molecular markers. As dispersed and ubiquitous transposable elements, their "copy and paste" life cycle of replicative transposition leads to new genome insertions without excision of the original element. Both the overall structure of retrotransposons and the domains responsible for the various phases of their replication are highly conserved in all eukaryotes. Nevertheless, up to a year has been required to develop a retrotransposon marker system in a new species, involving cloning and sequencing steps as well as the development of custom primers. Here, we describe a novel PCR-based method useful both as a marker system in its own right and for the rapid isolation of retrotransposon termini and full-length elements, making it ideal for "orphan crops" and other species with underdeveloped marker systems. The method, iPBS amplification, is based on the virtually universal presence of a tRNA complement as a reverse transcriptase primer binding site (PBS) in LTR retrotransposons. The method differs from earlier retrotransposon isolation methods because it is applicable not only to endogenous retroviruses and retroviruses, but also to both Gypsy and Copia LTR retrotransposons, as well as to non-autonomous LARD and TRIM elements, throughout the plant kingdom and to animals. Furthermore, the inter-PBS amplification technique as such has proved to be a powerful DNA fingerprinting technology without the need for prior sequence knowledge.

  7. The effect of water molecules on the thiol collector interaction on the galena (PbS) and sphalerite (ZnS) surfaces: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Long, Xianhao [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Chen, Ye, E-mail: fby18@126.com [College of Resources and Metallurgy, Guangxi University, Nanning 530004 (China); Chen, Jianhua, E-mail: jhchen@gxu.edu.cn [School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); College of Resources and Metallurgy, Guangxi University, Nanning 530004 (China); Xu, Zhenghe; Liu, Qingxia [Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB T6G 2V4 (Canada); Du, Zheng [National Supercomputing Center in Shenzhen, Shenzhen 518055 (China)

    2016-12-15

    Highlights: • Water adsorption has a greater effect on the electron distribution of ZnS surface than PbS surface. • Water adsorption decreases the reactivity of ZnS surface atoms but improves that of PbS. • Thiol collectors cannot interact with the hydrated ZnS surface. • The hydration has little influence on the interaction of thiol collectors with PbS surface. - Abstracts: In froth flotation the molecular interaction between reagents and mineral surfaces take place at the solid liquid interface. In this paper, the effect of water molecule on the three typical thiol collectors (xanthate, dithiocarbomate and dithiophosphate) interactions at the galena (PbS) and sphalerite (ZnS) surfaces has been studied adopting density functional theory (DFT). The results suggests that the presence of water molecule shows a greater influence on the electron distribution of ZnS surface than PbS surface, and reduce the reactivity of ZnS surface atoms but improves the reactivity of PbS surface atoms during the reaction with xanthate. Water adsorption could also reduce the covalent binding between Zn and S atoms but have little influence on Pb-S bond. In the presence of water, xanthate, dithiocarbomate (DTC) and dithiophosphate (DTP) could not adsorb on the sphalerite surface. And for galena (PbS) surface, the interaction of DTP is the strongest, then the DTC and the interaction of xanthate is the weakest. These results agree well with the flotation practice.

  8. Cost and Benefit Analysis of VSC-HVDC Schemes for Offshore Wind Power Transmission

    Institute of Scientific and Technical Information of China (English)

    Sheng WANG; Chunmei FENG; An WEN; Jun LIANG

    2013-01-01

    Due to low load factors of wind power generation,it is possible to reduce transmission capacity to minimize the cost of transmission system construction.Two VSC-HVDC schemes for offshore wind farm,called the point to point (PTP) and DC mesh connections are compared in terms of the utilization of transmission system and its cost.A Weibull distribution is used for estimating offshore wind power generation,besides,the cross correlation between wind farms is considered.The wind energy curtailment is analyzed using the capacity output possibility table (COPT).The system power losses,costs of transmission investment and wind energy curtailment are also computed.A statistic model for the wind generation and transmission is built and simulated in MATLAB to validate the study.It is concluded that a DC mesh transmission can reduce the energy curtailment and power losses.Further benefit is achievable as the wind cross correlation between wind farms decreases.

  9. Effect of national open apprenticeship scheme on youth employment ...

    African Journals Online (AJOL)

    Major problems of respondents in the scheme were, exclusion of some participants from resettlement benefits which accounted for 76.3% of the problem and insufficient resettlement package which accounted for 71.3% of the problem. Increasing the number of participants to benefit from the scheme's resettlement package ...

  10. Millisecond-Timescale Monitoring of PbS Nanoparticle Nucleation and Growth Using Droplet-Based Microfluidics.

    Science.gov (United States)

    Lignos, Ioannis; Stavrakis, Stavros; Kilaj, Ardita; deMello, Andrew J

    2015-08-26

    The early-time kinetics (conversion of precursor species to PbS crystals, followed by the growth of the formed particles. The growth kinetics of the PbS nanoparticles follow the Lifshitz-Slyozov-Wagner model for Ostwald ripening, allowing direct estimation of the rate constants for the process. In addition, the extraction of absorption spectra of ultrasmall quantum dots is demonstrated for first time in an online manner. The droplet-based microfluidic platform integrated with online spectroscopic analysis provides a new tool for the quantitative extraction of high temperature kinetics for systems with rapid nucleation and growth stages. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. "In the Footsteps of Alexander the Great" PBS Series. Teacher's Guide.

    Science.gov (United States)

    Corporation for Public Broadcasting, Washington, DC.

    This teacher's guide correlates with the Public Broadcasting Service (PBS) television series "In the Footsteps of Alexander the Great" hosted by historian Michael Wood. The four episodes of the series are entitled: "Son of God"; "Lord of Asia"; "Across the Hindu Kush"; and "To the Ends of the…

  12. Chemically synthesized PbS Nano particulate thin films for a rapid NO2 gas sensor

    Directory of Open Access Journals (Sweden)

    Burungale Vishal V.

    2016-03-01

    Full Text Available Rapid NO2 gas sensor has been developed based on PbS nanoparticulate thin films synthesized by Successive Ionic Layer Adsorption and Reaction (SILAR method at different precursor concentrations. The structural and morphological properties were investigated by means of X-ray diffraction and field emission scanning electron microscope. NO2 gas sensing properties of PbS thin films deposited at different concentrations were tested. PbS film with 0.25 M precursor concentration showed the highest sensitivity. In order to optimize the operating temperature, the sensitivity of the sensor to 50 ppm NO2 gas was measured at different operating temperatures, from 50 to 200 °C. The gas sensitivity increased with an increase in operating temperature and achieved the maximum value at 150 °C, followed by a decrease in sensitivity with further increase of the operating temperature. The sensitivity was about 35 % for 50 ppm NO2 at 150 °C with rapid response time of 6 s. T90 and T10 recovery time was 97 s at this gas concentration.

  13. Enhanced charge collection and photocatalysis performance of CdS and PbS nanoclusters co-sensitized TiO{sub 2} porous film

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Miao; Xu, Yanyan; Gong, Zezhou; Tao, Jiajia [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Sun, Zhaoqi, E-mail: szq@ahu.edu.cn [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Lv, Jianguo [School of Electronic & Information Engineering, Hefei Normal University, Hefei, 230601 (China); National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Chen, Xiaoshuang [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Jiang, Xishun [School of Physics & Material Science, Anhui University, Hefei 230601 (China); School of Mechanical & Electronic Engineering, Chuzhou University, Chuzhou, 239000 (China); He, Gang; Wang, Peihong; Meng, Fanming [School of Physics & Material Science, Anhui University, Hefei 230601 (China)

    2015-11-15

    A novel translucent TiO{sub 2} porous film was prepared through etched method. The CdS, PbS and CdS/PbS nanoclusters were imbedded on TiO{sub 2} porous film by successive ionic layer adsorption and reaction method. Microstructure, morphology, optical and photoelectron-chemical properties of the as-synthesized thin films were investigated systematically. XRD and morphology analysis showed that PbS or CdS nanoclusters have been attached to the TiO{sub 2} porous films. It was found that the energy band gap of TiO{sub 2} porous film decreased from 3.46 to 3.2 eV after sensitized with nanoclusters. The photocurrent density of ITO/TiO{sub 2} photoelectrode increased from 0.017 to 0.28 mA/cm{sup 2} after co-sensitized with CdS and PbS nanoclusters. Besides, the photoelectrode sensitized with two sorts of nanoclusters showed evident higher photocurrent density than which sensitized just one sort of nanoclusters. The photocurrent density of ITO/TiO{sub 2}/PbS and TO/TiO{sub 2}/CdS photoelectrode was 0.11 mA/cm{sup 2} and 0.22 mA/cm{sup 2} respectively. 0.28 mA/cm{sup 2} can be obtained by ITO/TiO{sub 2}/CdS/PbS photoelectrode. The results showed that the optical and photoelectrochemistry properties and phtotcatalysis performance of TiO{sub 2} porous film were greatly improved by co-sensitized with CdS and PbS nanoclusters. - Graphical abstract: When CdS and PbS were brought in the cascade structure, such a Fermi level alignment causes upward and downward shifts of the band edges for PbS and CdS, respectively. Therefore the resulting band edges for the ITO/TiO{sub 2}/CdS/PbS devices are inferred to have a stepwise structure. The elevated conduction band edge of PbS provides a higher driving force for the injection of photogenerated electrons from PbS to CdS as well as the injection of excited holes from CdS to PbS. Such a structure offers efficient separation and transport of the excited electrons and holes. - Highlights: • Ti films were obtained from direct current

  14. Sulfide precursor concentration and lead source effect on PbS thin films properties

    Energy Technology Data Exchange (ETDEWEB)

    Beddek, L.; Messaoudi, M.; Attaf, N. [Laboratoire Couche Minces et Interfaces, Université frères Mentouri Constantine, 25000, Constantine (Algeria); Aida, M.S., E-mail: aida_salah2@yahoo.fr [Laboratoire Couche Minces et Interfaces, Université frères Mentouri Constantine, 25000, Constantine (Algeria); Bougdira, J. [Université de Lorraine, Institut Jean Lamour UMR 7198, Vandoeuvre 54506 (France)

    2016-05-05

    Lead sulfide (PbS) thin films were synthesized using chemical bath deposition (CBD). Bath solutions are formed of various concentrations of thiourea, sulfide source, ranged from 0.6 to 1.2 M and two different salts as Pb source (lead acetate and lead nitrate). From the growth mechanism, we inferred that PbS is formed through the ion by ion process when using acetate lead source, while, using nitrate source yields to films growth through the complex-decomposition process. Due to the difference in the involved growth process, lead acetate produces films with larger crystallite size (from 4 to 16 nm), smooth and dense films. However, lead nitrate produces rough films with smaller crystallite size (from 1 to 4 nm). Increasing the thiourea concentration results in crystallinity improvement when using lead acetate and, oppositely, in crystallinity degradation when using lead nitrate. Due to the quantum effect caused by the small crystallite sizes, the films optical gap is varied from 0.5 to 0.9 eV. - Highlights: • PbS thin films were synthesized by chemical bath deposition. • Ion by ion is the growth process when using the acetate lead source. • Deposition process is by complex-decomposition when using nitrate source. • Lead acetate yields to dense films with larger crystallite size. • Lead nitrate produces rough films with smaller crystallite size.

  15. Sulfide precursor concentration and lead source effect on PbS thin films properties

    International Nuclear Information System (INIS)

    Beddek, L.; Messaoudi, M.; Attaf, N.; Aida, M.S.; Bougdira, J.

    2016-01-01

    Lead sulfide (PbS) thin films were synthesized using chemical bath deposition (CBD). Bath solutions are formed of various concentrations of thiourea, sulfide source, ranged from 0.6 to 1.2 M and two different salts as Pb source (lead acetate and lead nitrate). From the growth mechanism, we inferred that PbS is formed through the ion by ion process when using acetate lead source, while, using nitrate source yields to films growth through the complex-decomposition process. Due to the difference in the involved growth process, lead acetate produces films with larger crystallite size (from 4 to 16 nm), smooth and dense films. However, lead nitrate produces rough films with smaller crystallite size (from 1 to 4 nm). Increasing the thiourea concentration results in crystallinity improvement when using lead acetate and, oppositely, in crystallinity degradation when using lead nitrate. Due to the quantum effect caused by the small crystallite sizes, the films optical gap is varied from 0.5 to 0.9 eV. - Highlights: • PbS thin films were synthesized by chemical bath deposition. • Ion by ion is the growth process when using the acetate lead source. • Deposition process is by complex-decomposition when using nitrate source. • Lead acetate yields to dense films with larger crystallite size. • Lead nitrate produces rough films with smaller crystallite size.

  16. Improving 4D plan quality for PBS-based liver tumour treatments by combining online image guided beam gating with rescanning

    Science.gov (United States)

    Zhang, Ye; Knopf, Antje-Christin; Weber, Damien Charles; Lomax, Antony John

    2015-10-01

    Pencil beam scanned (PBS) proton therapy has many advantages over conventional radiotherapy, but its effectiveness for treating mobile tumours remains questionable. Gating dose delivery to the breathing pattern is a well-developed method in conventional radiotherapy for mitigating tumour-motion, but its clinical efficiency for PBS proton therapy is not yet well documented. In this study, the dosimetric benefits and the treatment efficiency of beam gating for PBS proton therapy has been comprehensively evaluated. A series of dedicated 4D dose calculations (4DDC) have been performed on 9 different 4DCT(MRI) liver data sets, which give realistic 4DCT extracting motion information from 4DMRI. The value of 4DCT(MRI) is its capability of providing not only patient geometries and deformable breathing characteristics, but also includes variations in the breathing patterns between breathing cycles. In order to monitor target motion and derive a gating signal, we simulate time-resolved beams’ eye view (BEV) x-ray images as an online motion surrogate. 4DDCs have been performed using three amplitude-based gating window sizes (10/5/3 mm) with motion surrogates derived from either pre-implanted fiducial markers or the diaphragm. In addition, gating has also been simulated in combination with up to 19 times rescanning using either volumetric or layered approaches. The quality of the resulting 4DDC plans has been quantified in terms of the plan homogeneity index (HI), total treatment time and duty cycle. Results show that neither beam gating nor rescanning alone can fully retrieve the plan homogeneity of the static reference plan. Especially for variable breathing patterns, reductions of the effective duty cycle to as low as 10% have been observed with the smallest gating rescanning window (3 mm), implying that gating on its own for such cases would result in much longer treatment times. In addition, when rescanning is applied on its own, large differences between volumetric

  17. Genetic analysis of the genus Diospyros ssp. using RAPD and i-PBS methods

    Directory of Open Access Journals (Sweden)

    Jana Raddová

    2012-01-01

    Full Text Available Molecular techniques (RAPD and i-PBS were used to study genetic diversity within persimmon collection at Horticulture Faculty of Mendel University in Lednice. The aim of the work was to distinguish 14 known and 6 of unknown origin persimmon cultivars. The basic screening of 20 OPT primers was applied to 4 cultivars differring in the place of origin. Within the group of screened primers there were chosen those, which gave polymorphic repeatable strong and middle strong bands. Selected primers were used for the RAPD reactions within the whole persimmon collection. Three OPA primers previously described in the literature were also used for the RAPD reactions within the whole persimmon collection. Additional 16 i-PBS primers previously described in the literature were also used for i-PBS analysis of the whole group of cultivars. Amplification was successful with 12 i-PBS primers. The FreeTree software package was used to gen­erate a similarity matrix and then to produce a dendrogram using UPGMA analyses. The similarity dendrograms of all persimmon cultivars were created based on both approaches and also on combination of both analyses by program Tree View. All the dendrograms clearly separated the assessed cultivars into 4 clusters. There are cluster of American persimmons – Meader’ (1, ’Garretson’ (2 and ’Early Golden’ (3. They are representatives of D. virginiana. Further part of dendrogram includes single D. lotus (5, which is also clearly separated from other cultivars of the genus Diospyros. The third cluster includes interspecific hybrids ’Rossiyanka’ (10 and ’Nikitskaiya Bordovaiya’ (13, which arised from crosses of D. virginiana and D. kaki. The last cluster is formed by cultivars of Japanese persimmon – ’Mikatani Gosho’, ’Zenjimaru’, ’Tone Wase’, ’Hiratanenashi’, ’Fuyu’, Chinese cultivar – ’Sansi’ and two Italian cultivars ’Vaniglia’ and ’Tipo’. They are clustered without significant

  18. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Science.gov (United States)

    2010-07-01

    ... background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2003-2007 $4.04 (5) For the performance of such a work in a... theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of such a work in a feature...

  19. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Science.gov (United States)

    2010-07-01

    ... background or theme music in a PBS program: 2008-2012 $57.66 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2008-2012 $4.10 (5) For the performance of such a work in a... theme music in an NPR program: 2008-2012 $5.59 (7) For the performance of such a work in a feature...

  20. Interfacial dynamic surface traps of lead sulfide (PbS) nanocrystals: test-platform for interfacial charge carrier traps at the organic/inorganic functional interface

    Science.gov (United States)

    Kim, Youngjun; Ko, Hyungduk; Park, Byoungnam

    2018-04-01

    Nanocrystal (NC) size and ligand dependent dynamic trap formation of lead sulfide (PbS) NCs in contact with an organic semiconductor were investigated using a pentacene/PbS field effect transistor (FET). We used a bilayer pentacene/PbS FET to extract information of the surface traps of PbS NCs at the pentacene/PbS interface through the field effect-induced charge carrier density measurement in the threshold and subthreshold regions. PbS size and ligand dependent trap properties were elucidated by the time domain and threshold voltage measurements in which threshold voltage shift occurs by carrier charging and discharging in the trap states of PbS NCs. The observed threshold voltage shift is interpreted in context of electron trapping through dynamic trap formation associated with PbS NCs. To the best of our knowledge, this is the first demonstration of the presence of interfacial dynamic trap density of PbS NC in contact with an organic semiconductor (pentacene). We found that the dynamic trap density of the PbS NC is size dependent and the carrier residence time in the specific trap sites is more sensitive to NC size variation than to NC ligand exchange. The probing method presented in the study offers a means to investigate the interfacial surface traps at the organic-inorganic hetero-junction, otherwise understanding of the buried surface traps at the functional interface would be elusive.

  1. Novel Random PBS-Based Copolymers Containing Aliphatic Side Chains for Sustainable Flexible Food Packaging

    Directory of Open Access Journals (Sweden)

    Giulia Guidotti

    2017-12-01

    Full Text Available In the last decade, there has been an increased interest from the food packaging industry toward the development and application of biodegradable and biobased plastics, to contribute to the sustainable economy and to reduce the huge environmental problem afflicting the planet. In this framework, the present paper describes the synthesis of novel PBS (poly(butylene succinate-based random copolymers with different composition containing glycol sub-units characterized by alkyl pendant groups of different length. The prepared samples were subjected to molecular, thermal, diffractometric and mechanical characterization. The barrier performances to O2, CO2 and N2 gases were also evaluated, envisioning for these new materials an application in food packaging. The presence of the side alkyl groups did not alter the thermal stability, whereas it significantly reduced the sample crystallinity degree, making these materials more flexible. The barrier properties were found to be worse than PBS; however, some of them were comparable to, or even better than, those of Low Density Polyethylene (LDPE, widely employed for flexible food packaging. The entity of variations in the final properties due to copolymerization were more modest in the case of the co-unit with short side methyl groups, which, when included in the PBS crystal lattice, causes a more modest decrement of crystallinity degree.

  2. Ultrafast exciton decay in PbS quantum dots through simultaneous electron and hole recombination with a surface-localized ion pair

    Energy Technology Data Exchange (ETDEWEB)

    Edme, Kedy; Bettis Homan, Stephanie; Nepomnyashchii, Alexander B.; Weiss, Emily A., E-mail: e-weiss@northwestern.edu

    2016-06-01

    Highlights: • We synthesize complexes of PbS quantum dots (QDs) and tetracyanoquinodimethane (TCNQ). Each PbS QD spontaneously reduces up to 17 TCNQ molecules. • The photoluminescence of the PbS QDs is quenched in the presence of the reduced TCNQ species through ultrafast non-radiative, simultaneous decay of the electron and hole. • We assign this decay to a four-carrier, concerted charge recombination mechanism with the surface localized sulfur–TCNQ{sup x−} ion pair. - Abstract: This paper describes the ultrafast decay of the band-edge exciton in PbS quantum dots (QDs) through simultaneous recombination of the excitonic hole and electron with the surface localized ion pair formed upon adsorption of tetracyanoquinodimethane (TCNQ). Each PbS QD (R = 1.8 nm) spontaneously reduces up to 17 TCNQ molecules upon adsorption of the TCNQ molecule to a sulfur on the QD surface. The photoluminescence of the PbS QDs is quenched in the presence of the reduced TCNQ species through ultrafast (⩽15-ps) non-radiative decay of the exciton; the rate constant for the decay process increases approximately linearly with the number of adsorbed, reduced TCNQ molecules. Near-infrared and mid-infrared transient absorption show that this decay occurs through simultaneous transfer of the excitonic electron and hole, and is assigned to a four-carrier, concerted charge recombination mechanism based on the observations that (i) the PL of the QDs recovers when spontaneously reduced TCNQ{sup 1−} desorbs from the QD surface upon addition of salt, and (ii) the PL of the QDs is preserved when another spontaneous oxidant, ferrocinium, which cannot participate in charge transfer in its reduced state, is substituted for TCNQ.

  3. Solution-processed nanocrystalline PbS on paper substrate with pencil traced electrodes as visible photodetector

    Science.gov (United States)

    Vankhade, Dhaval; Chaudhuri, Tapas K.

    2018-04-01

    Paper-based PbS photodetector sensitive in the visible spectrum is reported. Nanocrystalline PbS-on-paper devices are fabricated by a spin coating method on white paper (300 GSM) from a methanolic precursor solution. Photodetector cells of gap 0.2 cm and length 0.5 cm are prepared by drawing contacts by monolithic cretacolor 8B pencil. X-ray diffractometer confirmed the deposition of nanocrystalline PbS films with 14 nm crystallites. The SEM illustrated the uniform coating of nanocrystalline PbS thin films on cellulose fibres of papers having an average thickness of fibres are 10 µm. The linear J-V characteristics in dark and under illumination of light using graphite trace on nanocrystalline PbS-on-paper shows good ohmic contact. The resistivity of pencil trace is 30 Ω.cm. Spectral response measurements of photodetector reveal the excellent sensitivity from 400 to 700 nm with a peak at 550 nm. The best responsivity anddetectivity are 0.7 A/W and 1.4 × 1012 Jones respectively. These paper-based low-cost photodetectors devices have fast photoresponse and recovery without baseline deviation.

  4. Charge Carrier Conduction Mechanism in PbS Quantum Dot Solar Cells: Electrochemical Impedance Spectroscopy Study.

    Science.gov (United States)

    Wang, Haowei; Wang, Yishan; He, Bo; Li, Weile; Sulaman, Muhammad; Xu, Junfeng; Yang, Shengyi; Tang, Yi; Zou, Bingsuo

    2016-07-20

    With its properties of bandgap tunability, low cost, and substrate compatibility, colloidal quantum dots (CQDs) are becoming promising materials for optoelectronic applications. Additionally, solution-processed organic, inorganic, and hybrid ligand-exchange technologies have been widely used in PbS CQDs solar cells, and currently the maximum certified power conversion efficiency of 9.9% has been reported by passivation treatment of molecular iodine. Presently, there are still some challenges, and the basic physical mechanism of charge carriers in CQDs-based solar cells is not clear. Electrochemical impedance spectroscopy is a monitoring technology for current by changing the frequency of applied alternating current voltage, and it provides an insight into its electrical properties that cannot be measured by direct current testing facilities. In this work, we used EIS to analyze the recombination resistance, carrier lifetime, capacitance, and conductivity of two typical PbS CQD solar cells Au/PbS-TBAl/ZnO/ITO and Au/PbS-EDT/PbS-TBAl/ZnO/ITO, in this way, to better understand the charge carriers conduction mechanism behind in PbS CQD solar cells, and it provides a guide to design high-performance quantum-dots solar cells.

  5. Effect of Maleated Compatibiliser (PBS-g-MA) Addition on the Flexural Properties and Water Absorption of Poly(butylene succinate)/ kenaf Bast Fibre Composites

    International Nuclear Information System (INIS)

    Ahmad, M.Z.T.; Mohd, Z.A.M.; Mat, R.T.; Ahmad, M.Z.T.; Mohd, Z.A.I.; Mat, R.T.; Rahim, S.

    2013-01-01

    Poly(butylene succinate) (PBS) composites with 30 wt.% loading of kenaf bast fibre (KBF) were compatibilised with 5 wt. % maleated PBS (PBS-g-MA). The maleic anhydride (MA) concentration in the compatibiliser was either 3, 5, 7 or 10 phr. In general, the compatibilised composites showed better flexural properties than the un-compatibilised composite. The highest increment in the flexural strength and modulus of 12.7 and 8.9 %, respectively, were obtained with the addition of PBS-g-MA with MA concentration of 5 phr. Compatibilised and un-compatibilised PBS/ KBF composites were immersed in distilled water for 90 days. The absorption of water by all the composites was observed to follow Ficks law. The equilibrium moisture content, M m , of the composites with PBS-g-MA at 3, 5 and 7 phr of MA concentrations was lower than that of the un-compatibilised composite due to improved fiber-matrix interfacial adhesion and reduction of voids content. Both un-compatibilised and compatibilised composites showed dimensional instability after the water absorption. This was probably due to the degradation of the fibre-matrix interfacial adhesion and fibre integrity. The flexural properties of these composites decreased after the water absorption. After re-drying only some of the flexural properties were recovered from plasticizing effect of water. (author)

  6. The Effect of Substrate Temperature on the Structural Properties of Spray Pyrolysed Lead Sulphide (PbS Thin Films

    Directory of Open Access Journals (Sweden)

    Mohammad G. Faraj

    2014-09-01

    Full Text Available Lead sulphide (PbS films were prepared by the chemical spray pyrolysis technique using a solution of Lead nitrate and thiourea. PbS films were deposited (prepared on glass substrate at varied temperature (250-350 oC. Effects of substrate temperature on the structural characteristics of the films were studied. The X-ray diffraction patterns’ results reveal that the all of PbS films have a face centered cubic structure. The X-ray diffraction study showed that irrespective of substrate temperature all the films exhibits a preferred orientation along the (200 plane. The degree of preferred orientation increased with the substrate temperature. It was observed that the increase of the substrate temperature increase the diffraction peak intensity of (200 plane which resulted in increase in grain size and good crystallinity of the films.

  7. Probing surface states in PbS nanocrystal films using pentacene field effect transistors: controlling carrier concentration and charge transport in pentacene.

    Science.gov (United States)

    Park, Byoungnam; Whitham, Kevin; Bian, Kaifu; Lim, Yee-Fun; Hanrath, Tobias

    2014-12-21

    We used a bilayer field effect transistor (FET) consisting of a thin PbS nanocrystals (NCs) film interfaced with vacuum-deposited pentacene to probe trap states in NCs. We interpret the observed threshold voltage shift in context of charge carrier trapping by PbS NCs and relate the magnitude of the threshold voltage shift to the number of trapped carriers. We explored a series of NC surface ligands to modify the interface between PbS NCs and pentacene and demonstrate the impact of interface chemistry on charge carrier density and the FET mobility in a pentacene FET.

  8. Phase transformation and conductivity in nanocrystal PbS under pressure

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Gerward, Leif; Secco, R.

    2000-01-01

    The grain-size effect on the phase transition induced by pressure in PbS was studied by in situ high-pressure electrical resistance and synchrotron radiation x-ray powder diffraction measurements. The mean transition pressure of the B1-to-B16 phase transformation was found to be 6.3±1.3 GPa in 8...... in terms of a decrease of energy band gap with increasing pressure. ©2000 American Institute of Physics....

  9. Matroids and quantum-secret-sharing schemes

    International Nuclear Information System (INIS)

    Sarvepalli, Pradeep; Raussendorf, Robert

    2010-01-01

    A secret-sharing scheme is a cryptographic protocol to distribute a secret state in an encoded form among a group of players such that only authorized subsets of the players can reconstruct the secret. Classically, efficient secret-sharing schemes have been shown to be induced by matroids. Furthermore, access structures of such schemes can be characterized by an excluded minor relation. No such relations are known for quantum secret-sharing schemes. In this paper we take the first steps toward a matroidal characterization of quantum-secret-sharing schemes. In addition to providing a new perspective on quantum-secret-sharing schemes, this characterization has important benefits. While previous work has shown how to construct quantum-secret-sharing schemes for general access structures, these schemes are not claimed to be efficient. In this context the present results prove to be useful; they enable us to construct efficient quantum-secret-sharing schemes for many general access structures. More precisely, we show that an identically self-dual matroid that is representable over a finite field induces a pure-state quantum-secret-sharing scheme with information rate 1.

  10. Electrochemical surface-enhanced Raman scattering measurement on ligand capped PbS quantum dots at gap of Au nanodimer

    Science.gov (United States)

    Li, Xiaowei; Minamimoto, Hiro; Murakoshi, Kei

    2018-05-01

    The vibrational characteristics of ligand-capped lead sulfide (PbS) quantum dots (QDs) were clarified via electrochemical surface-enhanced Raman spectroscopy (EC-SERS) using a hybridized system of gold (Au) nanodimers and PbS QDs under electrochemical potential control. Enhanced electromagnetic field caused by the coupling of QDs with plasmonic Au nanodimers allowed the characteristic behavior of the ligand oleic acid (OA) on the PbS QD surface to be detected under electrochemical potential control. Binding modes between the QDs and OA molecules were characterized using synchronous two-dimensional correlation spectra at distinct electrochemical potentials, confirming that the bidentate bridging mode was probably the most stable mode even under relatively negative potential polarization. Changes in binding modes and molecular orientations resulted in fluctuations in EC-SERS spectra. The present observations strongly recommend the validity of the QD-plasmonic nanostructure coupled system for sensitive molecular detection via EC-SERS.

  11. Efficient 3M PBS enhancing miniature projection optics

    Science.gov (United States)

    Yun, Zhisheng; Nevitt, Timothy; Willett, Stephen; Mortenson, Dave; Le, John; McDowell, Erin; Kent, Susan; Wong, Timothy; Beniot, Gilles J.; Ouderkirk, Andrew

    2016-09-01

    Over the past decade, 3M has developed a number of mobile projectors, with a goal towards providing the world's smallest, most efficient projection systems. Compact size and efficiency are required characteristics for projection systems used in mobile devices and more lately, in augmented reality systems. In this paper we summarize the main generations of 3M light engine optical designs. We present the optical architectures of four light engines, including the rationale behind the illumination designs and the projection systems. In particular, we describe various configurations relating to the 3M polarizing beam splitter (PBS) which is key to enhanced efficiency of the miniature projection systems.

  12. Investigation of factors determining risk-taking strategies in Pension fund investment of Defined Benefit schemes in the UK corporate pension system

    OpenAIRE

    Hu, Chunan

    2014-01-01

    This paper investigates various incentives determining risk taking strategies of the corporate pension fund investment from the perspective of sponsors. In the United Kingdom, occupational pension plans especially defined benefit (DB) pension schemes play important roles in the financial market. Comparing with the conventional framework managing pension risk as a contained part of the whole firm risk, recent studies start to focus on pension risk especially investment risk as an individual to...

  13. Search for Spin Filtering By Electron Tunneling Through Ferromagnetic EuS Barriers in Pbs

    Science.gov (United States)

    Figielski, T.; Morawski, A.; Wosinski, T.; Wrotek, S.; Makosa, A.; Lusakowska, E.; Story, T.; Sipatov, A. Yu.; Szczerbakow, A.; Grasza, K.; hide

    2002-01-01

    Perpendicular transport through single- and double-barrier heterostructures consisting of ferromagnetic EuS layers embedded into PbS matrix was investigated. Manifestations of both resonant tunneling and spin filtering through EuS barrier have been observed.

  14. Opto-electronics of PbS quantum dot and narrow bandgap polymer blends

    NARCIS (Netherlands)

    Kahmann, Simon; Mura, Andrea; Protesescu, Loredana; Kovalenko, Maksym V.; Brabec, Christoph J.; Loi, Maria A.

    2015-01-01

    Here we report on the interaction between the narrow bandgap polymer [2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta-[2,1-b;3,4-b]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and lead sulphide (PbS) colloidal quantum dots (CQDs) upon photoexcitation. We show that the presence of both materials

  15. Benefit Reentitlement Conditions in Unemployment Insurance Schemes

    DEFF Research Database (Denmark)

    Andersen, Torben M.; Christoffersen, Mark Strøm; Svarer, Michael

    and employment requirements are substitute instruments in affecting job search incentives and thus gross unemployment. We analyse the optimal design of the unemployment insurance system (benefit levels, duration and employment requirements) under a utilitarian social welfare function. Simulations show...

  16. Size-dependent optical properties of colloidal PbS quantum dots.

    Science.gov (United States)

    Moreels, Iwan; Lambert, Karel; Smeets, Dries; De Muynck, David; Nollet, Tom; Martins, José C; Vanhaecke, Frank; Vantomme, André; Delerue, Christophe; Allan, Guy; Hens, Zeger

    2009-10-27

    We quantitatively investigate the size-dependent optical properties of colloidal PbS nanocrystals or quantum dots (Qdots), by combining the Qdot absorbance spectra with detailed elemental analysis of the Qdot suspensions. At high energies, the molar extinction coefficient epsilon increases with the Qdot volume d(3) and agrees with theoretical calculations using the Maxwell-Garnett effective medium theory and bulk values for the Qdot dielectric function. This demonstrates that quantum confinement has no influence on epsilon in this spectral range, and it provides an accurate method to calculate the Qdot concentration. Around the band gap, epsilon only increases with d(1.3), and values are comparable to the epsilon of PbSe Qdots. The data are related to the oscillator strength f(if) of the band gap transition and results agree well with theoretical tight-binding calculations, predicting a linear dependence of f(if) on d. For both PbS and PbSe Qdots, the exciton lifetime tau is calculated from f(if). We find values ranging between 1 and 3 mus, in agreement with experimental literature data from time-resolved luminescence spectroscopy. Our results provide a thorough general framework to calculate and understand the optical properties of suspended colloidal quantum dots. Most importantly, it highlights the significance of the local field factor in these systems.

  17. In Situ Passivation for Efficient PbS Quantum Dot Solar Cells by Precursor Engineering.

    Science.gov (United States)

    Wang, Yongjie; Lu, Kunyuan; Han, Lu; Liu, Zeke; Shi, Guozheng; Fang, Honghua; Chen, Si; Wu, Tian; Yang, Fan; Gu, Mengfan; Zhou, Sijie; Ling, Xufeng; Tang, Xun; Zheng, Jiawei; Loi, Maria Antonietta; Ma, Wanli

    2018-04-01

    Current efforts on lead sulfide quantum dot (PbS QD) solar cells are mostly paid to the device architecture engineering and postsynthetic surface modification, while very rare work regarding the optimization of PbS synthesis is reported. Here, PbS QDs are successfully synthesized using PbO and PbAc 2  · 3H 2 O as the lead sources. QD solar cells based on PbAc-PbS have demonstrated a high power conversion efficiency (PCE) of 10.82% (and independently certificated values of 10.62%), which is significantly higher than the PCE of 9.39% for PbO-PbS QD based ones. For the first time, systematic investigations are carried out on the effect of lead precursor engineering on the device performance. It is revealed that acetate can act as an efficient capping ligands together with oleic acid, providing better surface coverage and replace some of the harmful hydroxyl (OH) ligands during the synthesis. Then the acetate on the surface can be exchanged by iodide and lead to desired passivation. This work demonstrates that the precursor engineering has great potential in performance improvement. It is also pointed out that the initial synthesis is an often neglected but critical stage and has abundant room for optimization to further improve the quality of the resultant QDs, leading to breakthrough efficiency. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Tuning light emission of PbS nanocrystals from infrared to visible range by cation exchange

    KAUST Repository

    Binetti, Enrico

    2015-10-27

    Colloidal semiconductor nanocrystals, with intense and sharp-line emission between red and near-infrared spectral regions, are of great interest for optoelectronic and bio-imaging applications. The growth of an inorganic passivation layer on nanocrystal surfaces is a common strategy to improve their chemical and optical stability and their photoluminescence quantum yield. In particular, cation exchange is a suitable approach for shell growth at the expense of the nanocrystal core size. Here, the cation exchange process is used to promote the formation of a CdS passivation layer on the surface of very small PbS nanocrystals (2.3 nm in diameter), blue shifting their optical spectra and yielding luminescent and stable nanostructures emitting in the range of 700–850 nm. Structural, morphological and compositional investigation confirms the nanocrystal size contraction after the cation-exchange process, while the PbS rock-salt crystalline phase is retained. Absorption and photoluminescence spectroscopy demonstrate the growth of a passivation layer with a decrease of the PbS core size, as inferred by the blue-shift of the excitonic peaks. The surface passivation strongly increases the photoluminescence intensity and the excited state lifetime. In addition, the nanocrystals reveal increased stability against oxidation over time. Thanks to their absorption and emission spectral range and the slow recombination dynamics, such highly luminescent nano-objects can find interesting applications in sensitized photovoltaic cells and light-emitting devices.

  19. Tuning light emission of PbS nanocrystals from infrared to visible range by cation exchange

    KAUST Repository

    Binetti, Enrico; Striccoli, Marinella; Sibillano, Teresa; Giannini, Cinzia; Brescia, Rosaria; Falqui, Andrea; Comparelli, Roberto; Corricelli, Michela; Tommasi, Raffaele; Agostiano, Angela; Curri, M Lucia

    2015-01-01

    Colloidal semiconductor nanocrystals, with intense and sharp-line emission between red and near-infrared spectral regions, are of great interest for optoelectronic and bio-imaging applications. The growth of an inorganic passivation layer on nanocrystal surfaces is a common strategy to improve their chemical and optical stability and their photoluminescence quantum yield. In particular, cation exchange is a suitable approach for shell growth at the expense of the nanocrystal core size. Here, the cation exchange process is used to promote the formation of a CdS passivation layer on the surface of very small PbS nanocrystals (2.3 nm in diameter), blue shifting their optical spectra and yielding luminescent and stable nanostructures emitting in the range of 700–850 nm. Structural, morphological and compositional investigation confirms the nanocrystal size contraction after the cation-exchange process, while the PbS rock-salt crystalline phase is retained. Absorption and photoluminescence spectroscopy demonstrate the growth of a passivation layer with a decrease of the PbS core size, as inferred by the blue-shift of the excitonic peaks. The surface passivation strongly increases the photoluminescence intensity and the excited state lifetime. In addition, the nanocrystals reveal increased stability against oxidation over time. Thanks to their absorption and emission spectral range and the slow recombination dynamics, such highly luminescent nano-objects can find interesting applications in sensitized photovoltaic cells and light-emitting devices.

  20. Formal Model of Certificate Omission Schemes in VANET

    NARCIS (Netherlands)

    Feiri, Michael; Petit, Jonathan; Kargl, Frank

    2014-01-01

    The benefits of certificate omission schemes in VANET have been so far proven by simulation. However, the research community is lacking of a formal model that would allow implementers and policy makers to select the optimal parameters for such schemes. In this paper, we lay the foundations of the

  1. Improved performance of CdS/CdSe quantum dot-sensitized solar cells using Mn-doped PbS quantum dots as a catalyst in the counter electrode

    International Nuclear Information System (INIS)

    Kim, Byung-Man; Son, Min-Kyu; Kim, Soo-Kyoung; Hong, Na-Yeong; Park, Songyi; Jeong, Myeong-Soo; Seo, Hyunwoong; Prabakar, Kandasamy; Kim, Hee-Je

    2014-01-01

    Highlights: • PbS QDs synthesized using the SILAR method act not only as the electrochemical catalysts but as donors providing additional electrons under illumination. • The electrochemical and optical properties of the PbS QDs were enhanced considerably after Mn 2+ doping. • The electron supply from the counter electrode was significantly activated by Mn 2+ doping, improving the performance of QDSSC. - Abstract: This study reports the enhanced catalytic ability of Mn-doped PbS QDs synthesized using a successive ionic layer adsorption and reaction (SILAR) method for quantum dot-sensitized solar cells (QDSSCs). Electrochemical and optical analysis of each material showed that the catalytic ability of the PbS electrode was improved significantly by Mn 2+ doping. Two factors can explain this behavior. The first is that intentional impurities have an impact on the structure of the host material, such as increases in surface roughness. The other is that dopants create new energy states that delay the exciton recombination time and allow charge separation to be activated. As a result, the photoelectron supply from the counter electrode is accelerated, resulting in vigorous redox reactions at the polysulfide electrolyte. The performance of the CdS/CdSe QDSSC using a Mn-doped PbS counter electrode was compared with those using the Pt and PbS counter electrodes. Finally, a power conversion efficiency of 3.61% was achieved with the Mn-doped PbS counter electrode (V OC = 0.61 V, J SC = 11.67 mA cm −2 , FF = 0.51) under one sun illumination (100 mW cm −2 ), which is ∼40% higher than that of CdS/CdSe QDSSCs with the bare PbS counter electrode

  2. Social Protection Schemes in Pakistan: assessment of existing programs

    Directory of Open Access Journals (Sweden)

    Yu ShuHong

    2017-07-01

    Full Text Available Social protection is regarded as a basic human right guaranteed in several International Covenants and Treaties. The Constitution of Pakistan exclusively stipulates the provision of social security for all citizens of the country. The aim of the study is to explore and evaluate the social protection schemes with regards to its coverage, scope and outreach. The country has number of social security schemes that are being carried out by provincial and federal governments for the welfare of workers like old age benefits, disablement, health and medical facilities. However, these schemes have failed to extend their benefits to home based, part-time, temporary or contract and agricultural workers. This paper attempts to highlight the shortcomings of existing social protection programs that are obstructing their benefit distribution and limiting their outreach. It underlines the challenges faced by the implementing agencies. This paper also suggests some improvements in the structural design of social security mechanism with special focus on the scope, coverage, outreach and effective delivery mechanism. Since, the proper allocation of resources and effective implementation of these schemes can ensure the assistance and welfare of the targeted population.

  3. Developing and Rewarding Excellent Teachers: The Scottish Chartered Teacher Scheme

    Science.gov (United States)

    Ingvarson, Lawrence

    2009-01-01

    The Scottish Chartered Teacher Scheme was designed to recognise and reward teachers who attained high standards of practice. The scheme emerged in 2001 as part of an agreement between government, local employing authorities and teacher organisations. Policies such as the chartered teacher scheme aim to benefit students in two main ways: by…

  4. Cost-based droop scheme for DC microgrid

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  5. Combination of short-length TiO_2 nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

    International Nuclear Information System (INIS)

    Zhang, Zhengguo; Shi, Chengwu; Chen, Junjun; Xiao, Guannan; Li, Long

    2017-01-01

    Graphical abstract: The TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm"−"2 was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO_2 nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO_2 nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO_2 nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO_2 nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm"−"2 is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO_2 nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO_2 nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO_2 nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion efficiency of 4.10%, along with an open

  6. Recombination Suppression in PbS Quantum Dot Heterojunction Solar Cells by Energy-Level Alignment in the Quantum Dot Active Layers.

    Science.gov (United States)

    Ding, Chao; Zhang, Yaohong; Liu, Feng; Nakazawa, Naoki; Huang, Qingxun; Hayase, Shuzi; Ogomi, Yuhei; Toyoda, Taro; Wang, Ruixiang; Shen, Qing

    2017-09-22

    Using spatial energy-level gradient engineering with quantum dots (QDs) of different sizes to increase the generated carrier collection at the junction of a QD heterojunction solar cell (QDHSC) is a hopeful route for improving the energy-conversion efficiency. However, the results of current related research have shown that a variable band-gap structure in a QDHSC will create an appreciable increase, not in the illumination current density, but rather in the fill factor. In addition, there are a lack of studies on the mechanism of the effect of these graded structures on the photovoltaic performance of QDHSCs. This study presents the development of air atmosphere solution-processed TiO 2 /PbS QDs/Au QDHSCs by engineering the energy-level alignment (ELA) of the active layer via the use of a sorted order of differently sized QD layers (four QD sizes). In comparison to the ungraded device (without the ELA), the optimized graded architecture (containing the ELA) solar cells exhibited a great increase (21.4%) in short-circuit current density (J sc ). As a result, a J sc value greater than 30 mA/cm 2 has been realized in planar, thinner absorption layer (∼300 nm) PbS QDHSCs, and the open-circuit voltage (V oc ) and power-conversion efficiency (PCE) were also improved. Through characterization by the light intensity dependences of the J sc and V oc and transient photovoltage decay, we find that (i) the ELA structure, serving as an electron-blocking layer, reduces the interfacial recombination at the PbS/anode interface, and (ii) the ELA structure can drive more carriers toward the desirable collection electrode, and the additional carriers can fill the trap states, reducing the trap-assisted recombination in the PbS QDHSCs. This work has clearly elucidated the mechanism of the recombination suppression in the graded QDHSCs and demonstrated the effects of ELA structure on the improvement of J sc . The charge recombination mechanisms characterized in this work would be

  7. Publication Of Administrative Circulars: No. 4 (Rev. 4) – Unemployment Insurance Scheme No. 30 (Rev. 2) – Financial Benefits on Taking Up Appointment and on Termination of Contract

    CERN Multimedia

    HR Department

    2008-01-01

    Administrative Circular No. 4 (Rev. 4) – Unemployment insurance scheme Administrative Circular No. 4 (Rev. 4) – "Unemployment insurance scheme", approved following discussion in the Standing Concertation Committee meetings of 28 August 2007 and 27 February 2008, is now available on the intranet site of the Human Resources Department. It cancels and replaces Administrative Circular No. 4 (Rev. 3) – "Unemployment insurance" of October 1993. Copies will shortly be available in Departmental secretariats. Human Resources Department Tel. 78003 Administrative Circular No. 30 (Rev. 2) – Financial benefits on taking up appointment and termination of contract Administrative Circular No. 30 (Rev. 2) – "Financial benefits on taking up appointment and termination of contract", approved following discussion in the Standing Concertation Committee meetings of 28 August 2007 and 27 February 2008, is now available on the intranet site of the Human Resources De...

  8. Publication Of Administrative Circulars: No. 4 (Rev. 4) – Unemployment Insurance Scheme No. 30 (Rev. 2) – Financial Benefits on Taking Up Appointment and on Termination of Contract

    CERN Document Server

    HR Department

    2008-01-01

    Administrative Circular No. 4 (Rev. 4) – Unemployment insurance scheme Administrative Circular No. 4 (Rev. 4) – "Unemployment insurance scheme", approved following discussion at the Standing Concertation Committee meetings of 28 August 2007 and 27 February 2008, is now available on the intranet site of the Human Resources Department. It cancels and replaces Administrative Circular No. 4 (Rev. 3) – "Unemployment insurance" of October 1993. Copies will shortly be available in Departmental secretariats. Human Resources Department Tel. 78003 Administrative Circular No. 30 (Rev. 2) – Financial benefits on taking up appointment and termination of contract Administrative Circular No. 30 (Rev. 2) – "Financial benefits on taking up appointment and termination of contract", approved following discussion at the Standing Concertation Committee meetings of 28 August 2007 and 27 February 2008, is now available on the intranet site of the Human Resources De...

  9. Optimization of synthesis conditions of PbS thin films grown by chemical bath deposition using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Yücel, Ersin, E-mail: dr.ersinyucel@gmail.com [Department of Physics, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey); Yücel, Yasin; Beleli, Buse [Department of Chemistry, Faculty of Arts and Sciences, Mustafa Kemal University, 31034 Hatay (Turkey)

    2015-09-05

    Highlights: • For the first time, RSM and CCD used for optimization of PbS thin film. • Tri-sodium citrate, deposition time and temperature were independent variables. • PbS thin film band gap value was 2.20 eV under the optimum conditions. • Quality of the film was improved after chemometrics optimization. - Abstract: In this study, PbS thin films were synthesized by chemical bath deposition (CBD) under different deposition parameters. Response surface methodology (RSM) was used to optimize synthesis parameters including amount of tri-sodium citrate (0.2–0.8 mL), deposition time (14–34 h) and deposition temperature (26.6–43.4 °C) for deposition of the films. 5-level-3-factor central composite design (CCD) was employed to evaluate effects of the deposition parameters on the response (optical band gap of the films). The significant level of both the main effects and the interaction are investigated by analysis of variance (ANOVA). The film structures were characterized by X-ray diffractometer (XRD). Morphological properties of the films were studied with a scanning electron microscopy (SEM). The optical properties of the films were investigated using a UV–visible spectrophotometer. The optimum amount of tri-sodium citrate, deposition time and deposition temperature were found to be 0.7 mL, 18.07 h and 30 °C respectively. Under these conditions, the experimental band gap of PbS was 2.20 eV, which is quite good correlation with value (1.98 eV) predicted by the model.

  10. Optimization of synthesis conditions of PbS thin films grown by chemical bath deposition using response surface methodology

    International Nuclear Information System (INIS)

    Yücel, Ersin; Yücel, Yasin; Beleli, Buse

    2015-01-01

    Highlights: • For the first time, RSM and CCD used for optimization of PbS thin film. • Tri-sodium citrate, deposition time and temperature were independent variables. • PbS thin film band gap value was 2.20 eV under the optimum conditions. • Quality of the film was improved after chemometrics optimization. - Abstract: In this study, PbS thin films were synthesized by chemical bath deposition (CBD) under different deposition parameters. Response surface methodology (RSM) was used to optimize synthesis parameters including amount of tri-sodium citrate (0.2–0.8 mL), deposition time (14–34 h) and deposition temperature (26.6–43.4 °C) for deposition of the films. 5-level-3-factor central composite design (CCD) was employed to evaluate effects of the deposition parameters on the response (optical band gap of the films). The significant level of both the main effects and the interaction are investigated by analysis of variance (ANOVA). The film structures were characterized by X-ray diffractometer (XRD). Morphological properties of the films were studied with a scanning electron microscopy (SEM). The optical properties of the films were investigated using a UV–visible spectrophotometer. The optimum amount of tri-sodium citrate, deposition time and deposition temperature were found to be 0.7 mL, 18.07 h and 30 °C respectively. Under these conditions, the experimental band gap of PbS was 2.20 eV, which is quite good correlation with value (1.98 eV) predicted by the model

  11. Photoluminescence under high-electric field of PbS quantum dots

    Directory of Open Access Journals (Sweden)

    B. Ullrich

    2012-12-01

    Full Text Available The effect of a laterally applied electric field (≤10 kV/cm on the photoluminescence of colloidal PbS quantum dots (diameter of 2.7 nm on glass was studied. The field provoked a blueshift of the emission peak, a reduction of the luminescent intensity, and caused an increase in the full width at half maximum of the emission spectrum. Upon comparison with the photoluminescence of p-type GaAs exhibits the uniqueness of quantum dot based electric emission control with respect to bulk materials.

  12. Tn5-induced pBS286 plasmid mutations blocking early stages of napthalene oxidation

    International Nuclear Information System (INIS)

    Kosheleva, I.A.; Tsoi, T.V.; Ivashina, T.V.; Selifonov, S.A.; Starovoitov, I.I.; Boronin, A.M.

    1988-01-01

    The authors present data on the further analysis of the structural and functional organization of the nah region of plasmid pBS286 controlling the constitutive oxidation of naphthalene by Pseudomonas putida cells. They have studied Tn5-induced mutations blocking early stages of naphthalene oxidation. They present and discuss data providing evidence that, in contrast to plasmid NAH7, the mechanism of regulation of the nahl operon of plasmid NPL-1, the parent plasmid of plasmid pBS286, with inducible synthesis of naphthalene dioxygenase can include elements of a negative control with participation of the regulatory locus R, located proximal to the structural nah genes and closely linked to or overlapped by the inverted control DNA segment (4.2 kb). They also present data on the possibility of regulation of the activity of the catechol-splitting meta-pathway genes with the participation of products of early stages of naphthalene oxidation

  13. Enhanced Mobility-Lifetime Products in PbS Colloidal Quantum Dot Photovoltaics

    KAUST Repository

    Jeong, Kwang S.

    2012-01-24

    Figure Persented: Colloidal quantum dot (CQD) photovoltaics offer a promising approach to harvest the near-IR region of the solar spectrum, where half of the sun\\'s power reaching the earth resides. High external quantum efficiencies have been obtained in the visible region in lead chalcogenide CQD photovoltaics. However, the corresponding efficiencies for band gap radiation in the near-infrared lag behind because the thickness of CQD photovoltaic layers from which charge carriers can be extracted is limited by short carrier diffusion lengths. Here, we investigate, using a combination of electrical and optical characterization techniques, ligand passivation strategies aimed at tuning the density and energetic distribution of charge trap states at PbS nanocrystal surfaces. Electrical and optical measurements reveal a more than 7-fold enhancement of the mobility-lifetime product of PbS CQD films treated with 3-mercaptopropionic acid (MPA) in comparison to traditional organic passivation strategies that have been examined in the literature. We show by direct head-to-head comparison that the greater mobility-lifetime products of MPA-treated devices enable markedly greater short-circuit current and higher power conversion efficiency under AM1.5 illumination. Our findings highlight the importance of selecting ligand treatment strategies capable of passivating a diversity of surface states to enable shallower and lower density trap distributions for better transport and more efficient CQD solar cells. © 2011 American Chemical Society.

  14. High-performance PbS quantum dot vertical field-effect phototransistor using graphene as a transparent electrode

    Science.gov (United States)

    Che, Yongli; Zhang, Yating; Cao, Xiaolong; Song, Xiaoxian; Zhang, Haiting; Cao, Mingxuan; Dai, Haitao; Yang, Junbo; Zhang, Guizhong; Yao, Jianquan

    2016-12-01

    Solution processed photoactive PbS quantum dots (QDs) were used as channel in high-performance near-infrared vertical field-effect phototransistor (VFEpT) where monolayer graphene embedded as transparent electrode. In this vertical architecture, the PbS QD channel was sandwiched and naturally protected between the drain and source electrodes, which made the device ultrashort channel length (110 nm) simply the thickness of the channel layer. The VFEpT exhibited ambipolar operation with high mobilities of μe = 3.5 cm2/V s in n-channel operation and μh = 3.3 cm2/V s in p-channel operation at low operation voltages. By using the photoactive PbS QDs as channel material, the VFEpT exhibited good photoresponse properties with a responsivity of 4.2 × 102 A/W, an external quantum efficiency of 6.4 × 104% and a photodetectivity of 2.1 × 109 Jones at the light irradiance of 36 mW/cm2. Additionally, the VFEpT showed excellent on/off switching with good stability and reproducibility and fast response speed with a short rise time of 12 ms in n-channel operation and 10.6 ms in p-channel operation. These high mobilities, good photoresponse properties and simplistic fabrication of our VFEpTs provided a facile route to the high-performance inorganic photodetectors.

  15. Combination of short-length TiO{sub 2} nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhengguo [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); School of Chemistry and Chemical Engineering, Beifang University of Nationalities, Yinchuan 750021 (China); Shi, Chengwu, E-mail: shicw506@foxmail.com [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China); Chen, Junjun; Xiao, Guannan; Li, Long [School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009 (China)

    2017-07-15

    Graphical abstract: The TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, the areal density of 500 μm{sup −2} was successfully prepared. The compact PbS quantum-dot thin film was firstly obtained on the TiO{sub 2} nanorod array by spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol. The photoelectric conversion efficiency (PCE) of the compact PbS quantum-dot thin film sensitized solar cells achieved 4.10% using spiro-OMeTAD as a hole transporting layer, while the PCE of the PbS quantum-dot sensitized solar cells was only 0.54%. - Highlights: • Preparation of TiO{sub 2} nanorod arrays with the length of 600 nm, diameter of 20 nm. • The compact PbS QD thin film and short-length TiO{sub 2} nanorod array were combined. • EDT addition improved PbS nanoparticle coverage and photovoltaic performance. • The compact PbS QD thin film sensitized solar cell achieved the PCE of 4.10%. - Abstract: Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO{sub 2} nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm{sup −2} is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO{sub 2} nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO{sub 2} nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion

  16. 77 FR 35393 - Federal Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings

    Science.gov (United States)

    2012-06-13

    ... Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings AGENCY: Public Buildings... bulletin announces the designation and redesignation of three Federal buildings. Expiration Date: This bulletin announcement expires October 31, 2012. The building designation and redesignations remains in...

  17. Tunable and switchable all-fiber comb filter using a PBS-based two-stage cascaded Mach-Zehnder interferometer

    Science.gov (United States)

    Luo, Zhi-Chao; Luo, Ai-Ping; Xu, Wen-Cheng

    2011-08-01

    We propose and demonstrate a novel tunable and switchable all-fiber comb filter by employing a polarization beam splitter (PBS)-based two-stage cascaded Mach-Zehnder (M-Z) interferometer. The proposed comb filter consists of a rotatable polarizer, a fiber PBS, a non-3-dB coupler and a 3-dB coupler. By simply adjusting the polarization state of the input light, the dual-function of channel spacing tunable and wavelength switchable (interleaving) operations can be efficiently obtained. The theoretical analysis is verified by the experimental results. A comb filter with both the channel spacing tunable from 0.18 nm to 0.36 nm and the wavelength switchable functions is experimentally demonstrated.

  18. Purifying, concentrating and anhydriding bio-ethanol: Alternative process schemes and innovative separation methods

    International Nuclear Information System (INIS)

    Guerreri, G.; Lovati, A.

    1992-01-01

    Starting with the conventional process scheme for bio-ethanol production, this paper illustrates how the anhydriding section, which incorporates an azeotropic distillation process, can be conveniently substituted with a plate and frame pervaporation process which makes use of optimum heat exchange with the stripping section. This technical feasibility study, which proves the superior energy efficiency of the pervaporation scheme as compared with the conventional scheme, is followed by a cost benefit analysis which evidences the economic benefits also to be had with pervaporation

  19. Corrosion of experimental magnesium alloys in blood and PBS: A gravimetric and microscopic evaluation

    International Nuclear Information System (INIS)

    Schille, Ch.; Braun, M.; Wendel, H.P.; Scheideler, L.; Hort, N.; Reichel, H.-P.; Schweizer, E.; Geis-Gerstorfer, J.

    2011-01-01

    Highlights: ► Corrosion of eight Mg–based Biomaterials was tested in saline and human blood. ► Corrosion behaviour in physiological saline and in blood was entirely different. ► Al and Zn had the highest influence on corrosion behaviour in both electrolytes. ► MgAl9 and MgAl9Zn1 showed least corrosion in human whole blood. ► Tests in buffered corrosion media are not sufficient to predict corrosion in vivo. - Abstract: Corrosion tests for medical materials are often performed in simulated body fluids (SBF). When SBF are used for corrosion measurement, the open question is, how well they match the conditions in the human body. The aim of the study was to compare the corrosion behaviour of different experimental magnesium alloys in human whole blood and PBS minus (phosphate buffered saline w/o Ca and Mg) as a simulated body fluid by gravimetric weight measurements and microscopic evaluation. Eight different experimental magnesium alloys, containing neither Mn nor other additives, were manufactured. With these alloys, a static immersion test in PBS minus and a dynamic test using the Chandler-loop model with human whole blood over 6 h were performed. During the static immersion test, the samples were weighed every hour. During the dynamic test, the specimens were weighed before and after the 6 h incubation period in the Chandler-loop. From both tests, the total mass change was calculated for each alloy and the values were compared. Additionally, microscopic pictures from the samples were taken at the end of the test period. All alloys showed different corrosion behaviour in both tests, especially the alloys with high aluminium content, MgAl9 and MgAl9Zn1. Generally, alloys in PBS showed a weight gain due to generation of a microscopically visible corrosion layer, while in the blood test system a more or less distinct weight loss was observed. When alloys are ranked according to corrosion susceptibility, the results differ also between the test systems. The

  20. Effectiveness of the Swiss agri-environment scheme in promoting biodiversity

    NARCIS (Netherlands)

    Knop, E.; Kleijn, D.; Herzog, F.; Schmid, B.

    2006-01-01

    1. Increasing concern over the loss of biodiversity in agricultural landscapes was one of the reasons for the introduction of agri-environment schemes in Europe. These schemes compensate farmers financially for any loss of income associated with measures aimed to benefit biodiversity. Nevertheless,

  1. South African performance based standards (PBS) vehicle to transport steel pipes

    CSIR Research Space (South Africa)

    Dessein, T

    2010-03-01

    Full Text Available measures the vehicle?s rollover stability. Rearward Amplification (RA) ? Measures the degree to which the lateral accelerations experienced by trailing units are amplified in comparison to that of the towing unit in a high speed evasive single lane...-speed 90? turn high-speed travel along a 1.0km long straight road with uneven road surface a pulse-steer test HVTT11: A South African PBS Vehicle to Transport Pipes 10 a constant radius turn at slowly increasing speed an evasive lane change...

  2. Decoration of PbS nanoparticles on Al-doped ZnO nanorod array thin film with hydrogen treatment as a photoelectrode for solar water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Chih-Hsiung; Chen, Chao-Hong [Department of Chemical Engineering and Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Chen, Dong-Hwang, E-mail: chendh@mail.ncku.edu.tw [Department of Chemical Engineering and Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan, ROC (China)

    2013-03-25

    Highlights: ► AZO nanorod array thin film is used as a photoanode for solar water splitting. ► Hydrogen treatment and sensitization by PbS nanoparticles enhance photocurrent. ► A novel ITO/FTO-free composite photoelectrode is developed. ► The pre-fabrication and use of an extra TCO thin film substrate is unnecessary. -- Abstract: Al-doped ZnO (AZO) nanorod arrays thin film with hydrogen treatment is directly used as a photoelectrode for solar water splitting without an extra transparent conducting oxide (TCO) thin film because it possesses the functions of TCO thin film and photoactive 1-dimensional nanostructured semiconductor simultaneously. To enhance the absorption in the visible region, PbS nanoparticles decorated the AZO nanorods via successive ionic layer adsorption and reaction route. The PbS nanoparticles have a face-centered cubic structure and their decoration does not destroy the 1-dimensional morphology of AZO nanorod arrays. With increasing the cycle number of PbS nanoparticles decoration, the grain size and loading of PbS nanoparticles become larger gradually which leads to lower energy bandgap and stronger absorption. A maximum photocurrent density of 1.65 mW cm{sup −2} is obtained when the cycle number is 20, which is much higher than those without PbS nanoparticles sensitization or hydrogen treatment. This demonstrates that the AZO nanorod array thin film with hydrogen treatment can be directly used as a photoelectrode without an extra TCO thin film. Because the use of expensive metals can be avoided and the pre-fabrication of TCO thin film substrate is necessary no more, the fabrication of such a composite photoelectrode becomes simple and low-cost. So, it has great potentials in solar water splitting after sensitization by quantum dots capable of visible light absorption.

  3. Charge transfer between acenes and PbS nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Dissanayake, D M N M [Solid State Electronics Laboratory, University of Michigan, Ann Arbor, MI 48109-2122 (United States); Hatton, R A [Department of Chemistry, University of Warwick, Coventry CV4 7AL (United Kingdom); Lutz, T [Departments of Chemistry and Physics, Imperial College, London SW7 2AY (United Kingdom); Curry, R J; Silva, S R P [Advanced Technology Institute, University of Surrey, Guildford GU2 7XH (United Kingdom)], E-mail: ndissa@umich.edu

    2009-05-13

    Organic-inorganic hybrid heterojunctions have potential as the basis for future photovoltaic devices. Herein, we report the results of investigations exploring the possibility of using pentacene and tetracene as photoelectron donors in conjunction with PbS nanocrystals (PbS-NCs). Photoinduced charge transfer was probed using external quantum efficiency measurements on acene:PbS-NC hybrid photovoltaic devices in conjunction with photoluminescence studies of the corresponding bilayer films. It is shown that photoelectron transfer from pentacene to the PbS-NCs is inefficient as compared to that between tetracene and PbS-NCs. The latter case can be rationalized in terms of the energy level alignment at the heterojunction assuming a common vacuum level. However, in the case of pentacene:PbS-NC junctions an interfacial energy level shift must be considered in order to explain the observations.

  4. 2 W high efficiency PbS mid-infrared surface emitting laser

    Science.gov (United States)

    Ishida, A.; Sugiyama, Y.; Isaji, Y.; Kodama, K.; Takano, Y.; Sakata, H.; Rahim, M.; Khiar, A.; Fill, M.; Felder, F.; Zogg, H.

    2011-09-01

    High efficiency laser operation with output power exceeding 2 W was obtained for vertical external-cavity PbS based IV-VI compound surface emitting quantum-well structures. The laser showed external quantum efficiency as high as 16%. Generally, mid-infrared III-V or II-VI semiconductor laser operation utilizing interband electron transitions are restricted by Auger recombination and free carrier absorption. Auger recombination is much lower in the IV-VI semiconductors, and the free-carrier absorption is significantly reduced by an optically pumped laser structure including multi-step optical excitation layers.

  5. Entwicklung eines Summenparameters für potenziell bioakkumulierbare Stoffe (PBS) im Abwasser

    OpenAIRE

    Stenz, Georg

    2001-01-01

    Es wurde ein Summenparameter für potenziell bioakkumulierbare Stoffe (PBS) im Abwasser entwickelt. Der Summenparameter soll als Instrumentarium zur Überwachung von Einleitungen, Emissionen und Verlusten an anreicherungsfähigen Stoffen eingesetzt werden, da die Bioakkumulation besonders für marine Ökosysteme ein Gefährdungskriterium darstellt. Stoffe werden nach dem „Technical Guidance Document (TGD)“ als potenziell bioakkumulierbar bertrachtet, wenn deren log POW-Wert größer als drei ist. Der...

  6. A Reversible Photoacid Functioning in PBS Buffer under Visible Light.

    Science.gov (United States)

    Abeyrathna, Nawodi; Liao, Yi

    2015-09-09

    A metastable-state photoacid that can reversibly release a proton in PBS buffer (pH = 7.4) under visible light is reported. The design is based on the dual acid-base property and tautomerization of indazole. The quantum yield was as high as 0.73, and moderate light intensity (10(2) μmol·m(2)·s(-1)) is sufficient for the photoreaction. Reversible pH change of 1.7 units was demonstrated using a 0.1 mM aqueous solution. This type of photoacid is promising for control of proton-transfer processes in physiological conditions and may find applications in biomedical areas.

  7. Corrosion of experimental magnesium alloys in blood and PBS: A gravimetric and microscopic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Schille, Ch., E-mail: Christine.Schille@med.uni-tuebingen.de [University Hospital Tuebingen, Center for Dentistry, Oral Medicine and Maxillofacial Surgery, Section Medical Materials and Technology, Osianderstr. 2-8, D-72076 Tuebingen (Germany); Braun, M.; Wendel, H.P. [University Hospital Tuebingen, Div. Congenital and Paediatric Cardiac Surgery, University Children' s Hospital, Tuebingen, Germany, Calwerstr. 7/1, D-72076 Tuebingen (Germany); Scheideler, L. [University Hospital Tuebingen, Center for Dentistry, Oral Medicine and Maxillofacial Surgery, Section Medical Materials and Technology, Osianderstr. 2-8, D-72076 Tuebingen (Germany); Hort, N. [GKSS Research Centre, Institute of Materials Research, Max-Planck-Str. 1, D-21502 Geesthacht (Germany); Reichel, H.-P. [Weissensee Company, Buergermeister-Ebert-Str. 30-32, D-36124 Eichenzell (Germany); Schweizer, E.; Geis-Gerstorfer, J. [University Hospital Tuebingen, Center for Dentistry, Oral Medicine and Maxillofacial Surgery, Section Medical Materials and Technology, Osianderstr. 2-8, D-72076 Tuebingen (Germany)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer Corrosion of eight Mg-based Biomaterials was tested in saline and human blood. Black-Right-Pointing-Pointer Corrosion behaviour in physiological saline and in blood was entirely different. Black-Right-Pointing-Pointer Al and Zn had the highest influence on corrosion behaviour in both electrolytes. Black-Right-Pointing-Pointer MgAl9 and MgAl9Zn1 showed least corrosion in human whole blood. Black-Right-Pointing-Pointer Tests in buffered corrosion media are not sufficient to predict corrosion in vivo. - Abstract: Corrosion tests for medical materials are often performed in simulated body fluids (SBF). When SBF are used for corrosion measurement, the open question is, how well they match the conditions in the human body. The aim of the study was to compare the corrosion behaviour of different experimental magnesium alloys in human whole blood and PBS{sup minus} (phosphate buffered saline w/o Ca and Mg) as a simulated body fluid by gravimetric weight measurements and microscopic evaluation. Eight different experimental magnesium alloys, containing neither Mn nor other additives, were manufactured. With these alloys, a static immersion test in PBS{sup minus} and a dynamic test using the Chandler-loop model with human whole blood over 6 h were performed. During the static immersion test, the samples were weighed every hour. During the dynamic test, the specimens were weighed before and after the 6 h incubation period in the Chandler-loop. From both tests, the total mass change was calculated for each alloy and the values were compared. Additionally, microscopic pictures from the samples were taken at the end of the test period. All alloys showed different corrosion behaviour in both tests, especially the alloys with high aluminium content, MgAl9 and MgAl9Zn1. Generally, alloys in PBS showed a weight gain due to generation of a microscopically visible corrosion layer, while in the blood test system a more or less distinct weight

  8. A Framework for Identifying and Understanding Enterprise Systems Benefits

    DEFF Research Database (Denmark)

    Schubert, Petra; Williams, Susan P.

    2011-01-01

    Purpose – Identifying the benefits arising from implementations of enterprise systems and realizing business value remains a significant challenge for both research and industry. This paper aims to consolidate previous work. It presents a framework for investigating enterprise systems benefits...... into aspects and criteria plus an attributed appraisal value. The resulting scheme for the “three-level benefit codes” provides a greater level of detail about the nature of expected and realized benefits. Practical implications – The high level of detail and the code scheme comprising 60 different codes...... and the method for deriving the codes allows companies to identify and define benefits as well as to assess the outcome of enterprise systems implementation projects. Originality/value – The paper empirically develops an applicable benefits framework, which addresses the lack of detail of previous frameworks....

  9. 76 FR 54772 - Federal Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings

    Science.gov (United States)

    2011-09-02

    ... Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the designation and redesignation of two Federal buildings. Expiration Date: This bulletin announcement expires January 31, 2012. The building designation and redesignation remains in effect until...

  10. 75 FR 69080 - Federal Management Regulation; FMR Bulletin PBS-2010-B5; Redesignations of Federal Buildings

    Science.gov (United States)

    2010-11-10

    ... Management Regulation; FMR Bulletin PBS-2010-B5; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the designation and redesignation of two Federal buildings. DATES: Expiration Date: This bulletin announcement expires April 30, 2011. The building designation and redesignation remains in effect until...

  11. 76 FR 6792 - Federal Management Regulation; FMR Bulletin PBS-2011-B1; Redesignations of Federal Buildings

    Science.gov (United States)

    2011-02-08

    ... Management Regulation; FMR Bulletin PBS-2011-B1; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the redesignations of three Federal buildings. DATES: Expiration Date: This bulletin announcement expires June 30, 2011. The building redesignations remain in effect until canceled or superseded by...

  12. The deposition of highly uniform and adhesive nanocrystalline PbS film from solution

    International Nuclear Information System (INIS)

    Yang Yujun; Hu Shengshui

    2008-01-01

    Mirror-like PbS films have been deposited by chemical deposition on glass substrates from alkaline chemical bath containing lead nitrate, sodium thiosulfate and 1-thioglycerol, which was used to catalyze the hydrolysis of thiosulfate. Nanostructure characterization was carried out by x-ray diffraction and scanning electron microscopy in order to determine the average crystallite size (61 nm) and study the surface morphologies of the as-deposited films

  13. Comparative Evaluation of Cash Benefit Scheme of Janani Suraksha Yojana for Beneficiary Mothers from Different Health Care Settings of Rewa District, Madhya Pradesh, India.

    Directory of Open Access Journals (Sweden)

    Trivedi R

    2014-05-01

    Full Text Available Introduction: For better outcomes in mother and child health, Government of India launched the National Rural Health Mission (NRHM in 2005 with a major objective of providing accessible, affordable and quality health care to the rural population; especially the vulnerable. Reduction in MMR to 100/100,000 is one of its goals and the Janani Suraksha Yojana (JSY is the key strategy of NRHM to achieve this reduction. The JSY, as a safe motherhood intervention and modified alternative of the National Maternity Benefit Scheme (NMBS, has been implemented in all states and Union territories with special focus on low performing states. The main objective and vision of JSY is to reduce maternal, neo-natal mortality and promote institutional delivery among the poor pregnant women of rural and urban areas. This scheme is 100% centrally sponsored and has an integrated delivery and post delivery care with the help of a key person i.e. ASHA (Accredited Social Health Activist, followed by cash monetary help to the women. Objectives: 1To evaluate cash benefit service provided under JSY at different health care settings. 2 To know the perception and elicit suggestions of beneficiaries on quality of cash benefit scheme of JSY. Methodology: This is a health care institute based observational cross sectional study including randomly selected 200 JSY beneficiary mothers from the different health care settings i.e., Primary Health Centres, Community Health Centres, District Hospital and Medical College Hospital of Rewa District of Madhya Pradesh state. Data was collected with the help of set pro forma and then analysed with Epi Info 2000. Chi square test was applied appropriately. Results: 60% and 80% beneficiaries from PHC and CHC received cash within 1 week after discharge whereas 100% beneficiaries of District Hospital and Medical College Hospital received cash at the time of discharge; the overall distribution of time of cash disbursement among beneficiaries of

  14. Synthesis of single-crystal PbS nanorods via a simple hydrothermal process using PEO-PPO-PEO triblock copolymer as a structure-directing agent

    International Nuclear Information System (INIS)

    Bu Junfu; Nie Chageng; Liang Jinxia; Sun Lan; Xie Zhaoxiong; Wu Qi; Lin Changjian

    2011-01-01

    Single-crystal PbS nanorods were successfully synthesized through a simple hydrothermal route using PEO-PPO-PEO triblock copolymer (P123) as a structure-directing agent. The XRD pattern indicates that the crystal structure of the nanorods is face-centre-cubic rocksalt. A SEM image shows that the nanorods have a diameter of 40-70 nm and a length of 200-600 nm, and both tips exhibit taper-like structures. HRTEM and SAED images reveal the single-crystalline nature of the nanorods with the growth along the (111) direction. The experimental results indicated that the P123 concentration and reaction temperature played important roles in controlling the morphology of the PbS nanostructures. The optical property of PbS nanorods was investigated by UV-Vis absorption spectroscopy and the band structure was calculated by the B3LYP hybrid density functional theory.

  15. 75 FR 44264 - Federal Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building

    Science.gov (United States)

    2010-07-28

    ... Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building AGENCY: Public Buildings... announces the redesignation of a Federal building. DATES: Expiration Date: This bulletin expires December 31, 2010. However, the building redesignation announced by this bulletin will remain in effect until...

  16. Molecular diversity analysis of Tetradium ruticarpum (WuZhuYu) in China based on inter-primer binding site (iPBS) markers and inter-simple sequence repeat (ISSR) markers.

    Science.gov (United States)

    Xu, Jing-Yuan; Zhu, Yan; Yi, Ze; Wu, Gang; Xie, Guo-Yong; Qin, Min-Jian

    2018-01-01

    "Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum (A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and hypertension for thousands of years. The present study was designed to assess the molecular genetic diversity among 25 collected accessions of T. ruticarpum (Wu zhu yu in Chinese) from different areas of China, based on inter-primer binding site (iPBS) markers and inter-simple sequence repeat (ISSR) markers. Thirteen ISSR primers generated 151 amplification bands, of which 130 were polymorphic. Out of 165 bands that were amplified using 10 iPBS primers, 152 were polymorphic. The iPBS markers displayed a higher proportion of polymorphic loci (PPL = 92.5%) than the ISSR markers (PPL = 84.9%). The results showed that T. ruticarpum possessed high loci polymorphism and genetic differentiation occurred in this plant. The combined data of iPBS and ISSR markers scored on 25 accessions produced five clusters that approximately matched the geographic distribution of the species. The results indicated that both iPBS and ISSR markers were reliable and effective tools for analyzing the genetic diversity in T. ruticarpum. Copyright © 2018 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  17. Structure, transport and photoconductance of PbS quantum dot monolayers functionalized with a copper phthalocyanine derivative

    NARCIS (Netherlands)

    André, A.; Theurer, C.; Lauth, J.D.; Maiti, S.; Hodas, M.; Samadi Khoshkhoo, M.; Kinge, S; Meixner, A. J.; Schreiber, F.; Siebbeles, L.D.A.; Braun, K; Scheele, M.

    2017-01-01

    We simultaneously surface-functionalize PbS nanocrystals with Cu 4,4′,4′′,4′′′-tetraaminophthalocyanine and assemble this hybrid material into macroscopic monolayers. Electron microscopy and X-ray scattering reveal a granular mesocrystalline structure with strong coherence between the atomic

  18. Community benefits from offshore renewables: The relationship between different understandings of impact, community, and benefit

    DEFF Research Database (Denmark)

    Rudolph, David Philipp; Haggett, Claire; Aitken, Mhairi

    2018-01-01

    This paper presents the findings of a research project evaluating community benefit models for offshore renewables. We identify and analyse UK and international case studies of different forms of community benefit, and provide evidence of how such benefits are delivered. In particular we consider......, and impact are understood is crucial in determining whether or how benefits should be apportioned and delivered; and that these definitions are closely connected to each other. We develop a new series of typologies as a way to understand this. Finally, we assess different mechanisms and schemes of community...

  19. Biological conversion of anglesite (PbSO(4)) and lead waste from spent car batteries to galena (PbS).

    Science.gov (United States)

    Weijma, Jan; De Hoop, Klaas; Bosma, Wobby; Dijkman, Henk

    2002-01-01

    Lead paste, a solid mixture containing PbSO(4), PbO(2), PbO/Pb(OH)(2) precipitate, and elemental Pb, is one of the main waste fractions from spent car batteries. Biological sulfidation represents a new process for recovery of lead from this waste. In this process the lead salts in lead paste are converted to galena (PbS) by sulfate-reducing bacteria. This paper investigates a continuous process for sulfidation of anglesite (PbSO(4)), the main constituent of lead paste, and lead paste, consisting of a laboratory-scale gas-lift bioreactor to which a slurry of anglesite or lead paste was supplied. Sulfate or elemental sulfur was added as an additional sulfur source. Hydrogen gas served as an electron donor for the biological reduction of sulfate and elemental sulfur to sulfide by sulfate- and sulfur-reducing bacteria. Anglesite was almost completely converted to galena at a loading rate of 19 kg of PbSO(4) m(-)(3) day(-)(1), producing a sludge of which the crystalline lead phases consisted of >98% PbS (galena) and 1-2% elemental Pb. With lead paste, stable sulfidation rates of up to 17 kg of lead paste m(-)(3) day(-)(1) were demonstrated, producing a sludge of which the crystalline lead phases consisted of an estimated >96% PbS, 1-2% elemental Pb, and 1-2% PbO(2).

  20. The role of cationic precursors in structural, morphological and optical properties of PbS thin films

    International Nuclear Information System (INIS)

    Preetha, K C; Murali, K V; Ragina, A J; Deepa, K; Dhanya, A C; Remadevi, T L

    2013-01-01

    Thin films of Lead sulphide (PbS) were grown on soda lime glass substrate by Successive Ionic Layer Adsorption and Reaction (SILAR) method using lead acetate, lead chloride, lead nitrate, and lead sulphate as cationic precursors and thioacetamide as sulphur source. The experiments were carried out at room temperature under normal pressure utilizing aqueous conditions. The structural and morphological aspects of the as prepared samples were investigated by means of XRD and SEM results. The prepared samples were polycrystalline with nanometer-sized grains and identified as galena type cubic structure (FCC). The values of average crystallite size were found to be in the range 22 to 30 nm. The SEM micrographs show variations in morphology. Optical studies revealed that the absorption edges of the films indicated strong blue shifts with respect to bulk sample. In this work, we establish that the cationic precursor sources and in turn the size of the crystallites affects the structural, morphological and optical properties of PbS thin films.

  1. Evaluation of the Danish Leave Schemes. Summary of a Report.

    Science.gov (United States)

    Andersen, Dines; Appeldorn, Alice; Weise, Hanne

    An evaluation examined how the Danish leave schemes, an offer to employed and unemployed persons who qualify for unemployment benefits, were functioning and to what extent the objectives have been achieved. It was found that 60 percent of those taking leave had previously been unemployed; women accounted for two-thirds of those joining the scheme;…

  2. Benefits for handicapped children

    CERN Multimedia

    2003-01-01

    The introduction of long-term care benefits within the CERN Health Insurance Scheme requires the coordination of the benefits foreseen for handicapped children. Measures were adopted by the Management following the recommendation made by the Standing Concertation Committee on 26 March 2003. A document clarifying these measures is available on the Web at the following address: http://humanresources.web.cern.ch/humanresources/external/soc/Social_affairs/social_affairs.asp Social Affairs Service 74201

  3. Fabrication of PbS quantum dots and their applications in solar cells based on ZnO nanorod arrays

    Science.gov (United States)

    Kumar, Dinesh; Chaudhary, Sujeet; Pandya, Dinesh K.

    2018-05-01

    An efficient, inexpensive and large area scalable approach based on sol-gel technique is presented to fabricate quantum dots (QDs) of PbS. Size of the QDs is tuned by the varying the bath concentrations in the range of 50-200 mM. Transmission electron microscopy (TEM) studies confirm the growth of spherically shaped ˜5.6 nm QDs at 50 mM bath concentration. The optical bandgap of the QDs is found to be ˜0.9 eV and corresponds to the size obtained from TEM studies. ZnO/PbS solar cells are fabricated by sensitizing the ZnO nanorods with PbS QDs. The fabricated solar cells demonstrate the highest open circuit voltage ˜200 mV and short circuit current density ˜0.81 µA/cm2.

  4. Optical and electrical characterizations of a single step ion beam milling mesa devices of chloride passivated PbS colloidal quantum dots based film

    International Nuclear Information System (INIS)

    Hechster, Elad; Sarusi, Gabby; Shapiro, Arthur; Lifshitz, Efrat

    2016-01-01

    Colloidal Quantum Dots (CQDs) are of increasing interest, thanks to their quantum size effect that gives rise to their usage in various applications, such as biological tagging, solar cells and as the sensitizing layer of night vision devices. Here, we analyze the optical absorbance of chloride passivated PbS CQDs as well as revealing a correlation between their photoluminescence and sizes distribution, using theoretical models and experimental results from the literature. Next, we calculate the CQDs resistivity as a film. Although resistivity can be calculated from sheet resistance measurement using four point probes, such measurement is usually carried-out on the layer’s surface that in most cases has dangling bonds and surface states, which might affect the charges flow and modify the resistivity. Therefore; our approach, which was applied in this work, is to extract the actual resistivity from measurements that are performed along the film’s thickness (z-direction). For this intent, we fabricated gold capped PbS mesas devices using a single step Ion Beam Milling (IBM) process where we milled the gold and the PbS film continually, and then measured the vertical resistance. Knowing the mesas’ dimensions, we calculate the resistivity. To the best of our knowledge, no previous work has extracted, vertically, the resistivity of chloride passivated PbS CQDs using the above method.

  5. Optical and electrical characterizations of a single step ion beam milling mesa devices of chloride passivated PbS colloidal quantum dots based film

    Energy Technology Data Exchange (ETDEWEB)

    Hechster, Elad, E-mail: elad.hechster@gmail.com; Sarusi, Gabby [Electro-Optics Engineering Unit and Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, 84100 Israel (Israel); Shapiro, Arthur; Lifshitz, Efrat [Schulich Faculty of Chemistry, Solid State Institute, Russel Berrie Nanotechnology Institute, Technion – Israel Institute of technology, 32000 Haifa (Israel)

    2016-07-15

    Colloidal Quantum Dots (CQDs) are of increasing interest, thanks to their quantum size effect that gives rise to their usage in various applications, such as biological tagging, solar cells and as the sensitizing layer of night vision devices. Here, we analyze the optical absorbance of chloride passivated PbS CQDs as well as revealing a correlation between their photoluminescence and sizes distribution, using theoretical models and experimental results from the literature. Next, we calculate the CQDs resistivity as a film. Although resistivity can be calculated from sheet resistance measurement using four point probes, such measurement is usually carried-out on the layer’s surface that in most cases has dangling bonds and surface states, which might affect the charges flow and modify the resistivity. Therefore; our approach, which was applied in this work, is to extract the actual resistivity from measurements that are performed along the film’s thickness (z-direction). For this intent, we fabricated gold capped PbS mesas devices using a single step Ion Beam Milling (IBM) process where we milled the gold and the PbS film continually, and then measured the vertical resistance. Knowing the mesas’ dimensions, we calculate the resistivity. To the best of our knowledge, no previous work has extracted, vertically, the resistivity of chloride passivated PbS CQDs using the above method.

  6. The impact of different benefit packages of Medical Financial Assistance Scheme on health service utilization of poor population in rural China.

    Science.gov (United States)

    Hao, Yanhua; Wu, Qunhong; Zhang, Zhenzhong; Gao, Lijun; Ning, Ning; Jiao, Mingli; Zakus, David

    2010-06-17

    Since 2003 and 2005, National Pilot Medical Financial Assistance Scheme (MFA) has been implemented in rural and urban areas of China to improve the poorest families' accessibility to health services. Local governments of the pilot areas formulated various benefit packages. Comparative evaluation research on the effect of different benefit packages is urgently needed to provide evidence for improving policy-making of MFA. This study was based on a MFA pilot project, which was one component of Health VIII Project conducted in rural China. This article aimed to compare difference in health services utilization of poor families between two benefit package project areas: H8 towns (package covering inpatient service, some designated preventive and curative health services but without out-patient service reimbursement in Health VIII Project,) and H8SP towns (package extending coverage of target population, covering out- patient services and reducing co-payment rate in Health VIII Supportive Project), and to find out major influencing factors on their services utilization. A cross-sectional survey was conducted in 2004, which used stratified cluster sampling method to select poor families who have been enrolled in MFA scheme in rural areas of ChongQing. All family members of the enrolled households were interviewed. 748 and 1129 respondents from two kinds of project towns participated in the survey. Among them, 625 and 869 respondents were included (age>/=15) in the analysis of this study. Two-level linear multilevel model and binomial regressions with a log link were used to assess influencing factors on different response variables measuring service utilization. In general, there was no statistical significance in physician visits and hospitalizations among all the respondents between the two kinds of benefit package towns. After adjusting for major confounding factors, poor families in H8SP towns had much higher frequency of MFA use (beta = 1.17) and less use of

  7. Intergenerational risk sharing and endogenous labour supply within funded pension schemes

    NARCIS (Netherlands)

    Bonenkamp, J.; Westerhout, E.

    2014-01-01

    Funded defined-benefit pensions add to welfare on account of providing intergenerational risk sharing, but lower it on account of inducing labour supply distortions. We show that a properly designed funded defined-benefit pension scheme involves a welfare improvement even if contributions are

  8. Ultra high pressure homogenization (UHPH) inactivation of Bacillus amyloliquefaciens spores in phosphate buffered saline (PBS) and milk

    Science.gov (United States)

    Dong, Peng; Georget, Erika S.; Aganovic, Kemal; Heinz, Volker; Mathys, Alexander

    2015-01-01

    Ultra high pressure homogenization (UHPH) opens up new areas for dynamic high pressure assisted thermal sterilization of liquids. Bacillus amyloliquefaciens spores are resistant to high isostatic pressure and temperature and were suggested as potential surrogate for high pressure thermal sterilization validation. B. amyloliquefaciens spores suspended in PBS buffer (0.01 M, pH 7.0), low fat milk (1.5%, pH 6.7), and whole milk (3.5%, pH 6.7) at initial concentration of ~106 CFU/mL were subjected to UHPH treatments at 200, 300, and 350 MPa with an inlet temperature at ~80°C. Thermal inactivation kinetics of B. amyloliquefaciens spores in PBS and milk were assessed with thin wall glass capillaries and modeled using first-order and Weibull models. The residence time during UHPH treatments was estimated to determine the contribution of temperature to spore inactivation by UHPH. No sublethal injury was detected after UHPH treatments using sodium chloride as selective component in the nutrient agar medium. The inactivation profiles of spores in PBS buffer and milk were compared and fat provided no clear protective effect for spores against treatments. Treatment at 200 MPa with valve temperatures lower than 125°C caused no reduction of spores. A reduction of 3.5 log10CFU/mL of B. amyloliquefaciens spores was achieved by treatment at 350 MPa with a valve temperature higher than 150°C. The modeled thermal inactivation and observed inactivation during UHPH treatments suggest that temperature could be the main lethal effect driving inactivation. PMID:26236296

  9. The Benefits of Partnership Schemes to Schools and Research Students: A Case Study of the Researchers in Residence Scheme

    Science.gov (United States)

    Barley, Helen; Karim, Muhammed; Gilchrist, Myra; Gillies, Andrew

    2013-01-01

    To meet the needs of a modern Scottish society, a "Curriculum for Excellence" enables teachers to deliver a more coherent and skills-based curriculum, involving partnerships with external agencies. This article analyses the work of one host school/researcher team through the Researchers in Residence scheme in an Edinburgh secondary…

  10. Electron-Phonon Coupling and Resonant Relaxation from 1D and 1P States in PbS Quantum Dots.

    Science.gov (United States)

    Kennehan, Eric R; Doucette, Grayson S; Marshall, Ashley R; Grieco, Christopher; Munson, Kyle T; Beard, Matthew C; Asbury, John B

    2018-05-31

    Observations of the hot-phonon bottleneck, which is predicted to slow the rate of hot carrier cooling in quantum confined nanocrystals, have been limited to date for reasons that are not fully understood. We used time-resolved infrared spectroscopy to directly measure higher energy intraband transitions in PbS colloidal quantum dots. Direct measurements of these intraband transitions permitted detailed analysis of the electronic overlap of the quantum confined states that may influence their relaxation processes. In smaller PbS nanocrystals, where the hot-phonon bottleneck is expected to be most pronounced, we found that relaxation of parity selection rules combined with stronger electron-phonon coupling led to greater spectral overlap of transitions among the quantum confined states. This created pathways for fast energy transfer and relaxation that may bypass the predicted hot-phonon bottleneck. In contrast, larger, but still quantum confined nanocrystals did not exhibit such relaxation of the parity selection rules and possessed narrower intraband states. These observations were consistent with slower relaxation dynamics that have been measured in larger quantum confined systems. These findings indicated that, at small radii, electron-phonon interactions overcome the advantageous increase in energetic separation of the electronic states for PbS quantum dots. Selection of appropriately sized quantum dots, which minimize spectral broadening due to electron-phonon interactions while maximizing electronic state separation, is necessary to observe the hot-phonon bottleneck. Such optimization may provide a framework for achieving efficient hot carrier collection and multiple exciton generation.

  11. Quantum confinement-tunable ultrafast charge transfer at the PbS quantum dot and phenyl-C61-butyric acid methyl ester interface

    KAUST Repository

    El-Ballouli, AlA'A O.; Alarousu, Erkki Antero; Bernardi, Marco; Aly, Shawkat Mohammede; Lagrow, Alec P.; Bakr, Osman; Mohammed, Omar F.

    2014-01-01

    Quantum dot (QD) solar cells have emerged as promising low-cost alternatives to existing photovoltaic technologies. Here, we investigate charge transfer and separation at PbS QDs and phenyl-C61-butyric acid methyl ester (PCBM) interfaces using a combination of femtosecond broadband transient absorption (TA) spectroscopy and steady-state photoluminescence quenching measurements. We analyzed ultrafast electron injection and charge separation at PbS QD/PCBM interfaces for four different QD sizes and as a function of PCBM concentration. The results reveal that the energy band alignment, tuned by the quantum size effect, is the key element for efficient electron injection and charge separation processes. More specifically, the steady-state and time-resolved data demonstrate that only small-sized PbS QDs with a bandgap larger than 1 eV can transfer electrons to PCBM upon light absorption. We show that these trends result from the formation of a type-II interface band alignment, as a consequence of the size distribution of the QDs. Transient absorption data indicate that electron injection from photoexcited PbS QDs to PCBM occurs within our temporal resolution of 120 fs for QDs with bandgaps that achieve type-II alignment, while virtually all signals observed in smaller bandgap QD samples result from large bandgap outliers in the size distribution. Taken together, our results clearly demonstrate that charge transfer rates at QD interfaces can be tuned by several orders of magnitude by engineering the QD size distribution. The work presented here will advance both the design and the understanding of QD interfaces for solar energy conversion. © 2014 American Chemical Society.

  12. Quantum confinement-tunable ultrafast charge transfer at the PbS quantum dot and phenyl-C61-butyric acid methyl ester interface

    KAUST Repository

    El-Ballouli, AlA'A O.

    2014-05-14

    Quantum dot (QD) solar cells have emerged as promising low-cost alternatives to existing photovoltaic technologies. Here, we investigate charge transfer and separation at PbS QDs and phenyl-C61-butyric acid methyl ester (PCBM) interfaces using a combination of femtosecond broadband transient absorption (TA) spectroscopy and steady-state photoluminescence quenching measurements. We analyzed ultrafast electron injection and charge separation at PbS QD/PCBM interfaces for four different QD sizes and as a function of PCBM concentration. The results reveal that the energy band alignment, tuned by the quantum size effect, is the key element for efficient electron injection and charge separation processes. More specifically, the steady-state and time-resolved data demonstrate that only small-sized PbS QDs with a bandgap larger than 1 eV can transfer electrons to PCBM upon light absorption. We show that these trends result from the formation of a type-II interface band alignment, as a consequence of the size distribution of the QDs. Transient absorption data indicate that electron injection from photoexcited PbS QDs to PCBM occurs within our temporal resolution of 120 fs for QDs with bandgaps that achieve type-II alignment, while virtually all signals observed in smaller bandgap QD samples result from large bandgap outliers in the size distribution. Taken together, our results clearly demonstrate that charge transfer rates at QD interfaces can be tuned by several orders of magnitude by engineering the QD size distribution. The work presented here will advance both the design and the understanding of QD interfaces for solar energy conversion. © 2014 American Chemical Society.

  13. Consolidating the social health insurance schemes in China: towards an equitable and efficient health system.

    Science.gov (United States)

    Meng, Qingyue; Fang, Hai; Liu, Xiaoyun; Yuan, Beibei; Xu, Jin

    2015-10-10

    Fragmentation in social health insurance schemes is an important factor for inequitable access to health care and financial protection for people covered by different health insurance schemes in China. To fulfil its commitment of universal health coverage by 2020, the Chinese Government needs to prioritise addressing this issue. After analysing the situation of fragmentation, this Review summarises efforts to consolidate health insurance schemes both in China and internationally. Rural migrants, elderly people, and those with non-communicable diseases in China will greatly benefit from consolidation of the existing health insurance schemes with extended funding pools, thereby narrowing the disparities among health insurance schemes in fund level and benefit package. Political commitments, institutional innovations, and a feasible implementation plan are the major elements needed for success in consolidation. Achievement of universal health coverage in China needs systemic strategies including consolidation of the social health insurance schemes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. An authentication scheme for secure access to healthcare services.

    Science.gov (United States)

    Khan, Muhammad Khurram; Kumari, Saru

    2013-08-01

    Last few decades have witnessed boom in the development of information and communication technologies. Health-sector has also been benefitted with this advancement. To ensure secure access to healthcare services some user authentication mechanisms have been proposed. In 2012, Wei et al. proposed a user authentication scheme for telecare medical information system (TMIS). Recently, Zhu pointed out offline password guessing attack on Wei et al.'s scheme and proposed an improved scheme. In this article, we analyze both of these schemes for their effectiveness in TMIS. We show that Wei et al.'s scheme and its improvement proposed by Zhu fail to achieve some important characteristics necessary for secure user authentication. We find that security problems of Wei et al.'s scheme stick with Zhu's scheme; like undetectable online password guessing attack, inefficacy of password change phase, traceability of user's stolen/lost smart card and denial-of-service threat. We also identify that Wei et al.'s scheme lacks forward secrecy and Zhu's scheme lacks session key between user and healthcare server. We therefore propose an authentication scheme for TMIS with forward secrecy which preserves the confidentiality of air messages even if master secret key of healthcare server is compromised. Our scheme retains advantages of Wei et al.'s scheme and Zhu's scheme, and offers additional security. The security analysis and comparison results show the enhanced suitability of our scheme for TMIS.

  15. Financial incentive schemes in primary care

    Directory of Open Access Journals (Sweden)

    Gillam S

    2015-09-01

    Full Text Available Stephen Gillam Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Cambridge, UK Abstract: Pay-for-performance (P4P schemes have become increasingly common in primary care, and this article reviews their impact. It is based primarily on existing systematic reviews. The evidence suggests that P4P schemes can change health professionals' behavior and improve recorded disease management of those clinical processes that are incentivized. P4P may narrow inequalities in performance comparing deprived with nondeprived areas. However, such schemes have unintended consequences. Whether P4P improves the patient experience, the outcomes of care or population health is less clear. These practical uncertainties mirror the ethical concerns of many clinicians that a reductionist approach to managing markers of chronic disease runs counter to the humanitarian values of family practice. The variation in P4P schemes between countries reflects different historical and organizational contexts. With so much uncertainty regarding the effects of P4P, policy makers are well advised to proceed carefully with the implementation of such schemes until and unless clearer evidence for their cost–benefit emerges. Keywords: financial incentives, pay for performance, quality improvement, primary care

  16. ‘Green’-synthesized near-infrared PbS quantum dots with silica-PEG dual-layer coating: ultrastable and biocompatible optical probes for in vivo animal imaging

    Science.gov (United States)

    Wang, D.; Qian, J.; Cai, F.; He, S.; Han, S.; Mu, Y.

    2012-06-01

    In this paper, PbS semiconductor quantum dots (QDs) with near-infrared (NIR) photoluminescence were synthesized in oleic acid and paraffin liquid mixture by using an easily handled and ‘green’ approach. Surface functionalization of the QDs was accomplished with a silica and polyethylene glycol (PEG) phospholipid dual-layer coating and the excellent chemical stability of the nanoparticles is demonstrated. We then successfully applied the ultrastable PbS QDs to in vivo sentinel lymph node (SLN) mapping of mice. Histological analyses were also carried out to ensure that the intravenously injected nanoparticles did not produce any toxicity to the organism of mice. These experimental results suggested that our ultrastable NIR PbS QDs can serve as biocompatible and efficient probes for in vivo optical bioimaging and has great potentials for disease diagnosis and clinical therapies in the future.

  17. ‘Green’-synthesized near-infrared PbS quantum dots with silica–PEG dual-layer coating: ultrastable and biocompatible optical probes for in vivo animal imaging

    International Nuclear Information System (INIS)

    Wang, D; Qian, J; Cai, F; He, S; Han, S; Mu, Y

    2012-01-01

    In this paper, PbS semiconductor quantum dots (QDs) with near-infrared (NIR) photoluminescence were synthesized in oleic acid and paraffin liquid mixture by using an easily handled and ‘green’ approach. Surface functionalization of the QDs was accomplished with a silica and polyethylene glycol (PEG) phospholipid dual-layer coating and the excellent chemical stability of the nanoparticles is demonstrated. We then successfully applied the ultrastable PbS QDs to in vivo sentinel lymph node (SLN) mapping of mice. Histological analyses were also carried out to ensure that the intravenously injected nanoparticles did not produce any toxicity to the organism of mice. These experimental results suggested that our ultrastable NIR PbS QDs can serve as biocompatible and efficient probes for in vivo optical bioimaging and has great potentials for disease diagnosis and clinical therapies in the future. (paper)

  18. Realization of PbS thin films by reactive evaporation technique for possible opto-electronic applications

    Energy Technology Data Exchange (ETDEWEB)

    A, Abhilash, E-mail: abhiltp@cusat.ac.in; Nair, Aparna S.; S, Rajasree; E, Hiba Rahman; Pradeep, B. [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi-682022 (India)

    2015-06-24

    Stoichiometric Lead sulphide (PbS) thin films were successfully prepared on glass substrates by reactive evaporation technique. Elemental evaporation of lead and sulphur taken in different sources onto substrates held at temperature of 400±5K employed in the present study. The structural as well as compositional studies compromises compound formation. Electrical transport properties and optical co-efficient were evaluated from appropriate characterization techniques.

  19. Supercritical synthesis and in situ deposition of PbS nanocrystals with oleic acid passivation for quantum dot solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tavakoli, M.M. [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Simchi, A., E-mail: simchi@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Institute for Nanoscience and Nanotechnology, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of); Aashuri, H. [Department of Materials Science and Engineering, Sharif University of Technology, 14588 Tehran (Iran, Islamic Republic of)

    2015-04-15

    Colloidal quantum dot solar cells have recently attracted significant attention due to their low-processing cost and surging photovoltaic performance. In this paper, a novel, reproducible, and simple solution-based process based on supercritical fluid toluene is presented for in situ growth and deposition PbS nanocrystals with oleic-acid passivation. A lead precursor containing sulfur was mixed with oleic acid in toluene and processed in a supercritical fluid condition at different temperatures of 140, 270 and 330 °C for 20 min. The quantum dots were deposited on a fluorine-doped tin oxide glass substrate inside the supercritical reactor. Transmission electron microscopy, X-ray diffraction, absorption and dynamic light scattering showed that the nanocrystals processed at the supercritical condition (330 °C) are fully crystalline with a narrow size distribution of ∼3 nm with an absorption wavelength of 915 nm (bandgap of 1.3 eV). Fourier transform infrared spectroscopy indicated that the PbS quantum dots are passivated by oleic acid molecules during the growth. Photovoltaic characteristics of Schottky junction solar cells showed an improvement over devices prepared by spin-coating. - Highlights: • Supercritical fluid processing and in situ deposition of PbS QDs are presented. • The prepared nanocrystals are mono-dispersed with an optical bandgap of 1.3 eV. • Photovoltaic performance of the in situ deposited nanocrystals is reported. • An improved PV performance compared to spin coated Schottky solar cells is shown.

  20. Additive operator-difference schemes splitting schemes

    CERN Document Server

    Vabishchevich, Petr N

    2013-01-01

    Applied mathematical modeling isconcerned with solving unsteady problems. This bookshows how toconstruct additive difference schemes to solve approximately unsteady multi-dimensional problems for PDEs. Two classes of schemes are highlighted: methods of splitting with respect to spatial variables (alternating direction methods) and schemes of splitting into physical processes. Also regionally additive schemes (domain decomposition methods)and unconditionally stable additive schemes of multi-component splitting are considered for evolutionary equations of first and second order as well as for sy

  1. TU-H-BRC-03: Evaluation of Very High-Energy Electron (VHEE) Beams in Comparison to VMAT and PBS Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, E; Loo, B; Maxim, P [Stanford University School of Medicine, Palo Alto, California (United States); Eriksson, K; Hynning, E [RaySearch Laboratories, Stockholm (Sweden)

    2016-06-15

    Purpose: The aim of this study was to evaluate the performance of very high-energy electron (VHEE) beams in comparison to clinically delivered treatment plans generated with volumetric modulated arc therapy (VMAT) and proton pencil beam scanning (PBS) technology. Methods: Three clinical cases were selected (prostate, lung, and pediatric CNS). The VHEE plans were calculated in the Monte Carlo EGSnrc code and pencil beam doses were calculated using the DOSxyznrc MC code for 100 and 200 MeV beams. Treatment plans with VHEE, VMAT, and PBS were optimized in a research version of RayStation using an in house build script in order to minimize operator bias between the different techniques. Results: For the prostate cancer case, the PBS plan showed lower mean organ at risk (OAR) doses compared to the other modalities. An exception was the femoral heads, due to the lateral beam arrangements. The VMAT plan showed lower mean doses to the rectum and the bladder compared to the 100 MeV VHEE plan. The lung cancer case showed minor differences between the three modalities. However, the PBS plan showed a lower contralateral lung dose. The pediatric CNS case showed a better conformity and lower spinal cord dose for the 100 MeV VHEE plan. For all cases, the 200 MeV VHEE plans were found to be similar to or better than the 100 MeV VHEE plans. Conclusion: The present study showed that VHEE plans are similar or superior to VMAT plans with reduced mean OAR dose and increased target conformity for a variety of clinical cases. With increased VHEE energy, better conformity and even higher reductions in mean OAR doses can be achieved. Funding: DoD, Award#:W81XWH-13-1-0165, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation. BL and PM are founders of TibaRay,Inc. BL and PM have received research grants from Varian and RaySearch Laboratory.

  2. SU-F-T-185: Study of the Robustness of a Proton Arc Technique Based On PBS Beams

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z [Reading Hospital, West Reading, PA (United States); Zheng, Y [Procure Proton Therapy Center, Oklahoma City, OK (United States)

    2016-06-15

    Purpose: One potential technique to realize proton arc is through using PBS beams from many directions to form overlaid Bragg peak (OBP) spots and placing these OBP spots throughout the target volume to achieve desired dose distribution. In this study, we analyzed the robustness of this proton arc technique. Methods: We used a cylindrical water phantom of 20 cm in radius in our robustness analysis. To study the range uncertainty effect, we changed the density of the phantom by ±3%. To study the setup uncertainty effect, we shifted the phantom by 3 & 5 mm. We also combined the range and setup uncertainties (3mm/±3%). For each test plan, we performed dose calculation for the nominal and 6 disturbed scenarios. Two test plans were used, one with single OBP spot and the other consisting of 121 OBP spots covering a 10×10cm{sup 2} area. We compared the dose profiles between the nominal and disturbed scenarios to estimate the impact of the uncertainties. Dose calculation was performed with Gate/GEANT based Monte Carlo software in cloud computing environment. Results: For each of the 7 scenarios, we simulated 100k & 10M events for plans consisting of single OBP spot and 121 OBP spots respectively. For single OBP spot, the setup uncertainty had minimum impact on the spot’s dose profile while range uncertainty had significant impact on the dose profile. For plan consisting of 121 OBP spots, similar effect was observed but the extent of disturbance was much less compared to single OBP spot. Conclusion: For PBS arc technique, range uncertainty has significantly more impact than setup uncertainty. Although single OBP spot can be severely disturbed by the range uncertainty, the overall effect is much less when a large number of OBP spots are used. Robustness optimization for PBS arc technique should consider range uncertainty with priority.

  3. SU-F-T-185: Study of the Robustness of a Proton Arc Technique Based On PBS Beams

    International Nuclear Information System (INIS)

    Wang, Z; Zheng, Y

    2016-01-01

    Purpose: One potential technique to realize proton arc is through using PBS beams from many directions to form overlaid Bragg peak (OBP) spots and placing these OBP spots throughout the target volume to achieve desired dose distribution. In this study, we analyzed the robustness of this proton arc technique. Methods: We used a cylindrical water phantom of 20 cm in radius in our robustness analysis. To study the range uncertainty effect, we changed the density of the phantom by ±3%. To study the setup uncertainty effect, we shifted the phantom by 3 & 5 mm. We also combined the range and setup uncertainties (3mm/±3%). For each test plan, we performed dose calculation for the nominal and 6 disturbed scenarios. Two test plans were used, one with single OBP spot and the other consisting of 121 OBP spots covering a 10×10cm"2 area. We compared the dose profiles between the nominal and disturbed scenarios to estimate the impact of the uncertainties. Dose calculation was performed with Gate/GEANT based Monte Carlo software in cloud computing environment. Results: For each of the 7 scenarios, we simulated 100k & 10M events for plans consisting of single OBP spot and 121 OBP spots respectively. For single OBP spot, the setup uncertainty had minimum impact on the spot’s dose profile while range uncertainty had significant impact on the dose profile. For plan consisting of 121 OBP spots, similar effect was observed but the extent of disturbance was much less compared to single OBP spot. Conclusion: For PBS arc technique, range uncertainty has significantly more impact than setup uncertainty. Although single OBP spot can be severely disturbed by the range uncertainty, the overall effect is much less when a large number of OBP spots are used. Robustness optimization for PBS arc technique should consider range uncertainty with priority.

  4. Unemployment Benefits as Redistribution Scheme of Trade Gains - a Positive Analysis

    OpenAIRE

    de Pinto, Marco

    2012-01-01

    Trade liberalization is no Pareto-improvement . there are winners (high-skilled) and losers (low-skilled). To compensate the losers the government is assumed to introduce unemployment benefits (UB). These benefits are financed by either a wage tax, a payroll tax, or a profit tax. Using a Melitz -type model of international trade with unionized labour markets and heterogeneous workers we show that: (i) UB .financed by a wage tax reduce aggregate employment but increase welfare measured by per ...

  5. Quasiparticle self-consistent GW calculations for PbS, PbSe, and PbTe: Band structure and pressure coefficients

    DEFF Research Database (Denmark)

    Svane, Axel; Christensen, Niels Egede; Cardona,, M.

    2010-01-01

    The electronic band structures of PbS, PbSe, and PbTe in the rocksalt structure are calculated with the quasiparticle self-consistent GW (QSGW) approach with spin-orbit coupling included. The semiconducting gaps and their deformation potentials as well as the effective masses are obtained. The GW...

  6. Cadillac Desert: Water and the Transformation of Nature. A Discussion and Viewer's Guide to the PBS Series.

    Science.gov (United States)

    McDowell, Ceasar L.; Reisner, Marc; Bonk, Laura; Wisehart, Bob

    Cadillac Desert is a four-part Public Broadcasting Service (PBS) video series on the remaking of America's West through startling feats of engineering and the consequences that this manipulation of water and nature has wrought. This guide is meant to serve as a resource for discussing the issues raised in the series. The first part of the guide…

  7. Origins of Stokes shift in PbS nanocrystals

    KAUST Repository

    Voznyy, Oleksandr

    2017-10-27

    Stokes shift, an energy difference between the excitonic absorption and emission, is a property of colloidal quantum dots (CQDs) typically ascribed to splitting between dark and bright excitons. In some materials, e.g., PbS, CuInS2, CdHgTe, a Stokes shift of up to 200 meV is observed, substantially larger than the estimates of dark-bright state splitting or vibronic relaxations. The shift origin remains highly debated, as contradictory signatures of both surface and bulk character were reported for the Stokes-shifted electronic state. Here we show that the energy transfer among CQDs in a polydispersed ensemble in solution suffices to explain the excess Stokes shift. This energy transfer is primarily due to CQD aggregation, and can be substantially eliminated by extreme dilution, higher-viscosity solvent, or better-dispersed colloids. Our findings highlight that ensemble polydispersity remains the primary source of the Stokes shift in CQDs in solution, propagating into the Stokes shift in films and the open-circuit voltage deficit in CQD solar cells. Improved synthetic control can bring notable advancements in CQD photovoltaics, and the Stokes shift continues to provide a sensitive and significant metric to monitor ensemble size distribution.

  8. Ultra high pressure homogenization (UHPH inactivation of Bacillus amyloliquefaciens spores in phosphate buffered saline (PBS and milk

    Directory of Open Access Journals (Sweden)

    Peng eDong

    2015-07-01

    Full Text Available Ultra high pressure homogenization (UHPH opens up new areas for dynamic high pressure assisted thermal sterilization of liquids. Bacillus amyloliquefaciens spores are resistant to high isostatic pressure and temperature and were suggested as potential surrogate for high pressure thermal sterilization validation. B. amyloliquefaciens spores suspended in PBS buffer (0.01 M, pH 7.0, low fat milk (1.5%, pH 6.7 and whole milk (3.5%, pH 6.7 at initial concentration of ~106 CFU/mL were subjected to UHPH treatments at 200, 300 and 350 MPa with an inlet temperature at ~80 °C. Thermal inactivation kinetics of B. amyloliquefaciens spores in PBS and milk were assessed with thin wall glass capillaries and modeled using mechanistic linear first order and Weibull models. The residence time during UHPH treatments was estimated to determine the contribution of temperature to spore inactivation by UHPH. No sublethal injury was detected after UHPH treatments using sodium chloride as selective component in the nutrient agar medium. The inactivation profiles of spores in PBS buffer and milk were compared and fat provided no clear protective effect for spores against treatments. Treatment at 200 MPa with valve temperatures lower than 125 °C caused no reduction of spores. A reduction of 3.5 log10 CFU/mL of B. amyloliquefaciens spores was achieved by treatment at 350 MPa with a valve temperature higher than 150 °C. The modeled thermal inactivation and observed inactivation during UHPH treatments suggest that temperature could be the main lethal effect driving inactivation.

  9. Modification of Morphological, Structural and Optical Properties of CBD-Based Growth of PbS Films on Glass Substrates by Addition of Saccharin

    Directory of Open Access Journals (Sweden)

    Yasin YÜCEL

    2018-03-01

    Full Text Available Saccharin which so-called as benzoic sulfimide is an artificial sweetener. In this paper, nanostructured lead sulfide (PbS thin films were produced in the presence of additive known as saccharin via chemical bath deposition (CBD. Effect of the saccharin content on the morphological, optical and structural properties of the films has been investigated. Lead sulfide (PbS films that included additive were prepared at five different concentrations of saccharin (from 0 to 5%. The fabricated samples were characterized by surface roughness, scanning electron microscopy (SEM, X-Ray diffraction and UV-vis spectroscopy. It was found that the presence of saccharin highly affected the optical and structural properties of PbS thin films. According to the X-Ray diffraction results, crystallite size values of the films decreased from 12.88 to 5.25 nm with increasing of saccharin content. UV-vis measurements showed that both the band gap and transmission properties of the films increased as a result of increasing saccharin concentration. Further, Surface roughness measurements exhibited that average surface roughness was diminished with increasing saccharin content. As a result, it has been found that the presence of saccharin in growth solution played a significant mission in adjusting the main physical properties of the samples.

  10. Molecular and Supramolecular Changes in Polybutylene Succinate (PBS and Polybutylene Succinate Adipate (PBSA Copolymer during Degradation in Various Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Michał Puchalski

    2018-03-01

    Full Text Available In this paper, the influence of the various degradation conditions, on the molecular and supramolecular structure of polybutylene succinate (PBS and polybutylene succinate adipate (PBSA copolymer during degradation is described. The experiment was carried out by the use of injection molded samples and normalized conditions of biodegradation in soil, composting and artificial weathering. Materials were studied by size-exclusion chromatography (SEC coupled with multiangle laser light scattering (MALLS detection and wide-angle X-ray diffraction (WAXD. Additionally, the physical and mechanical properties of the samples were determined. The performed experiments clearly show difference impacts of the selected degradation conditions on the macroscopic, supramolecular and molecular parameters of the studied aliphatic polyesters. The structural changes in PBS and PBSA explain the observed changes in the physical and mechanical properties of the obtained injection molded samples.

  11. Spontaneous interfacial reaction between metallic copper and PBS to form cupric phosphate nanoflower and its enzyme hybrid with enhanced activity.

    Science.gov (United States)

    He, Guangli; Hu, Weihua; Li, Chang Ming

    2015-11-01

    We herein report the spontaneous interfacial reaction between copper foil with 0.01 M phosphate buffered saline (PBS) to form free-standing cupric phosphate (Cu3(PO4)2) nanoflowers at ambient temperature. The underlying chemistry was thoroughly investigated and it is found that the formation of nanoflower is synergistically caused by dissolved oxygen, chlorine ions and phosphate ions. Enzyme-Cu3(PO4)2 hybrid nanoflower was further prepared successfully by using an enzyme-dissolving PBS solution and the enzymes in the hybrid exhibit enhanced biological activity. This work provides a facile route for large-scale synthesis of hierarchical inorganic and functional protein-inorganic hybrid architectures via a simple one-step solution-immersion reaction without using either template or surfactant, thus offering great potential for biosensing application among others. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Anticollusion Attack Noninteractive Security Hierarchical Key Agreement Scheme in WHMS

    Directory of Open Access Journals (Sweden)

    Kefei Mao

    2016-01-01

    Full Text Available Wireless Health Monitoring Systems (WHMS have potential to change the way of health care and bring numbers of benefits to patients, physicians, hospitals, and society. However, there are crucial barriers not only to transmit the biometric information but also to protect the privacy and security of the patients’ information. The key agreement between two entities is an essential cryptography operation to clear the barriers. In particular, the noninteractive hierarchical key agreement scheme becomes an attractive direction in WHMS because each sensor node or gateway has limited resources and power. Recently, a noninteractive hierarchical key agreement scheme has been proposed by Kim for WHMS. However, we show that Kim’s cryptographic scheme is vulnerable to the collusion attack if the physicians can be corrupted. Obviously, it is a more practical security condition. Therefore, we proposed an improved key agreement scheme against the attack. Security proof, security analysis, and experimental results demonstrate that our proposed scheme gains enhanced security and more efficiency than Kim’s previous scheme while inheriting its qualities of one-round communication and security properties.

  13. A Practical Scheme to Quantify Safety Benefits of Disaster Robots

    International Nuclear Information System (INIS)

    Choi, Young; Jeong, Kyungmin; Kim, Inn Seock

    2016-01-01

    The nuclear robotics team of KAERI is also endeavoring to construct disaster robots, and first of all, interested in how much safety benefits the disaster robots will bring about. The nuclear robotics team of Korea Atomic Energy Research Institute (KAERI) has long been involved in robot development for a variety of applications such as emergency refueling manipulation at a pressurized heavy water reactor and decommissioning of nuclear power plants. In light of great advances these days in remote response technology and the need to upgrade the coping capabilities of the nuclear power plants against beyond-design-basis external events, a primary focus is placed on developing disaster robots that can be deployed to the field where a disastrous or potentially disastrous event is happening. Where a decision has to be made to select a robotic mitigating measure out of several alternatives, the approach also may be applied in evaluating the safety benefit for each alternative so that the result can be used in the selection process together with other decision factors. As part of the fundamental research in the robotics development program of KAERI, a new approach to quantify the safety benefits associated with the mitigation actions to be implemented by disaster robots in the case of an extreme nuclear accident has been developed. This approach is based on a PRA model, and seismic-induced station blackout condition was used as the target scenario. Where a decision has to be made to select a robotic mitigating measure out of several alternatives, the approach also may be applied in evaluating the safety benefit for each alternative so that the result can be used in the selection process along with other decision factors (e.g., development costs, technical feasibility). Although only the action of starting and aligning the SBO diesel generator was used as a mitigating measure that might be performed by the disaster robots in this study, they could also be used for many

  14. A Practical Scheme to Quantify Safety Benefits of Disaster Robots

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young; Jeong, Kyungmin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Inn Seock [ISSA Technology, Germantown (United States)

    2016-10-15

    The nuclear robotics team of KAERI is also endeavoring to construct disaster robots, and first of all, interested in how much safety benefits the disaster robots will bring about. The nuclear robotics team of Korea Atomic Energy Research Institute (KAERI) has long been involved in robot development for a variety of applications such as emergency refueling manipulation at a pressurized heavy water reactor and decommissioning of nuclear power plants. In light of great advances these days in remote response technology and the need to upgrade the coping capabilities of the nuclear power plants against beyond-design-basis external events, a primary focus is placed on developing disaster robots that can be deployed to the field where a disastrous or potentially disastrous event is happening. Where a decision has to be made to select a robotic mitigating measure out of several alternatives, the approach also may be applied in evaluating the safety benefit for each alternative so that the result can be used in the selection process together with other decision factors. As part of the fundamental research in the robotics development program of KAERI, a new approach to quantify the safety benefits associated with the mitigation actions to be implemented by disaster robots in the case of an extreme nuclear accident has been developed. This approach is based on a PRA model, and seismic-induced station blackout condition was used as the target scenario. Where a decision has to be made to select a robotic mitigating measure out of several alternatives, the approach also may be applied in evaluating the safety benefit for each alternative so that the result can be used in the selection process along with other decision factors (e.g., development costs, technical feasibility). Although only the action of starting and aligning the SBO diesel generator was used as a mitigating measure that might be performed by the disaster robots in this study, they could also be used for many

  15. Broadcast Reserved Opportunity Assisted Diversity Relaying Scheme and Its Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Xia Chen

    2008-05-01

    Full Text Available Relay-based transmission can over the benefits in terms of coverage extension as well as throughput improvement if compared to conventional direct transmission. In a relay enhanced cellular (REC network, where multiple mobile terminals act as relaying nodes (RNs, multiuser diversity gain can be exploited. We propose an efficient relaying scheme, referred to as Broadcast Reserved Opportunity Assisted Diversity (BROAD for the REC networks. Unlike the conventional Induced Multiuser Diversity Relaying (IMDR scheme, our scheme acquires channel quality information (CQI in which the destined node (DN sends pilots on a reserved radio resource. The BROAD scheme can significantly decrease the signaling overhead among the mobile RNs while achieving the same multiuser diversity as the conventional IMDR scheme. In addition, an alternative version of the BROAD scheme, named as A-BROAD scheme, is proposed also, in which the candidate RN(s feed back partial or full CQI to the base station (BS for further scheduling purpose. The A-BROAD scheme achieves a higher throughput than the BROAD scheme at the cost of extra signalling overhead. The theoretical analysis given in this paper demonstrates the feasibility of the schemes in terms of their multiuser diversity gains in a REC network.

  16. Designing an Efficient Retransmission Scheme for Wireless LANs: Theory and Implementation

    OpenAIRE

    Koutsonikolas, Dimitrios; Wang, Chih-Chun; Hu, Y Charlie; Shroff, Ness

    2010-01-01

    Network coding is known to benefit the downlink retransmissions by the AP in a wireless LAN from exploiriting overhearing at the client nodes. However, designing an efficient and practical retransmission scheme remains a challange. We present an (asymptotically) optimal scheme, ECR, for reduing the downlink retransmissions by the AP in a wireless LAN from exploiting overhearing at the client nodes. The design of ECR, consisting of three components: batch-based operations, a systematic pha...

  17. SU-E-T-262: Planning for Proton Pencil Beam Scanning (PBS): Applications of Gradient Optimization for Field Matching

    Energy Technology Data Exchange (ETDEWEB)

    Lin, H; Kirk, M; Zhai, H; Ding, X; Liu, H; Hill-Kayser, C; Lustig, R; Tochner, Z; Deville, C; Vapiwala, N; McDonough, J; Both, S [University Pennsylvania, Philadelphia, PA (United States)

    2014-06-01

    Purpose: To propose the gradient optimization(GO) approach in planning for matching proton PBS fields and present two commonly used applications in our institution. Methods: GO is employed for PBS field matching in the scenarios that when the size of the target is beyond the field size limit of the beam delivery system or matching is required for beams from different angles to either improve the sparing of important organs or to pass through a short and simple beam path. Overlap is designed between adjacent fields and in the overlapped junction, the dose was optimized such that it gradually decreases in one field and the decrease is compensated by increase from another field. Clinical applications of this approach on craniospinal irradiation(CSI) and whole pelvis treatment were presented. Mathematical model was developed to study the relationships between dose errors, setup errors and junction lengths. Results: Uniform and conformal dose coverage to the entire target volumes was achieved for both applications using GO approach. For CSI, the gradient matching (6.7cm junction) between fields overcame the complexity of planning associated with feathering match lines. A slow dose gradient in the junction area significantly reduced the sensitivity of the treatment to setup errors. For whole pelvis, gradient matching (4cm junction) between posterior fields for superior target and bilateral fields for inferior target provided dose sparing to organs such as bowel, bladder and rectum. For a setup error of 3 mm in longitudinal direction from one field, mathematical model predicted dose errors of 10%, 6% and 4.3% for junction length of 3, 5 and 7cm. Conclusion: This GO approach improves the quality of the PBS treatment plan with matching fields while maintaining the safety of treatment delivery relative to potential misalignments.

  18. SU-E-T-262: Planning for Proton Pencil Beam Scanning (PBS): Applications of Gradient Optimization for Field Matching

    International Nuclear Information System (INIS)

    Lin, H; Kirk, M; Zhai, H; Ding, X; Liu, H; Hill-Kayser, C; Lustig, R; Tochner, Z; Deville, C; Vapiwala, N; McDonough, J; Both, S

    2014-01-01

    Purpose: To propose the gradient optimization(GO) approach in planning for matching proton PBS fields and present two commonly used applications in our institution. Methods: GO is employed for PBS field matching in the scenarios that when the size of the target is beyond the field size limit of the beam delivery system or matching is required for beams from different angles to either improve the sparing of important organs or to pass through a short and simple beam path. Overlap is designed between adjacent fields and in the overlapped junction, the dose was optimized such that it gradually decreases in one field and the decrease is compensated by increase from another field. Clinical applications of this approach on craniospinal irradiation(CSI) and whole pelvis treatment were presented. Mathematical model was developed to study the relationships between dose errors, setup errors and junction lengths. Results: Uniform and conformal dose coverage to the entire target volumes was achieved for both applications using GO approach. For CSI, the gradient matching (6.7cm junction) between fields overcame the complexity of planning associated with feathering match lines. A slow dose gradient in the junction area significantly reduced the sensitivity of the treatment to setup errors. For whole pelvis, gradient matching (4cm junction) between posterior fields for superior target and bilateral fields for inferior target provided dose sparing to organs such as bowel, bladder and rectum. For a setup error of 3 mm in longitudinal direction from one field, mathematical model predicted dose errors of 10%, 6% and 4.3% for junction length of 3, 5 and 7cm. Conclusion: This GO approach improves the quality of the PBS treatment plan with matching fields while maintaining the safety of treatment delivery relative to potential misalignments

  19. Immune modulating effects of NKT cells in a physiologically low dose Leishmania major infection model after αGalCer analog PBS57 stimulation.

    Science.gov (United States)

    Griewank, Klaus G; Lorenz, Beate; Fischer, Michael R; Boon, Louis; Lopez Kostka, Susanna; von Stebut, Esther

    2014-06-01

    Leishmaniasis is a parasitic infection affecting ∼12 million people worldwide, mostly in developing countries. Treatment options are limited and no effective vaccines exist to date. Natural Killer T (NKT) cells are a conserved innate-like lymphocyte population with immunomodulating effects in various settings. A number of reports state a role of NKT cells in different models of Leishmania infection. Here, we investigated the effect of NKT cells in a physiologically relevant, intradermal low dose infection model. After inoculation of 103 infectious-stage L. major, comparable numbers of skin-immigrating NKT cells in both susceptible BALB/c mice and resistant C57BL/6 mice were noted. Compared to their wild type counterparts, NKT cell-deficient mice on a C57BL/6 background were better able to contain infection with L. major and showed decreased IL-4 production in cytokine analysis performed 5 and 8 weeks after infection. Low doses of the NKT cell stimulating αGalCer analog PBS57 applied at the time of infection led to disease exacerbation in C57BL/6 wild-type, but not NKT-deficient mice. The effect was dependent both on the timing and amount of PBS57 administered. The effect of NKT cell stimulation by PBS57 proved to be IL-4 dependent, as it was neutralized in IL-4-deficient C57BL/6 or anti-IL-4 antibody-treated wild-type mice. In contrast to C57BL/6 mice, administration of PBS57 in susceptible BALB/c mice resulted in an improved course of disease. Our results reveal a strain- and cytokine-dependent regulatory role of NKT cells in the development of immunity to low dose L. major infections. These effects, probably masked in previous studies using higher parasite inocula, should be considered in future therapy and immunization approaches.

  20. The Australian Managed Entry Scheme: Are We Getting it Right?

    Science.gov (United States)

    Tuffaha, Haitham W; Scuffham, Paul A

    2018-05-01

    In 2010, the Australian Government introduced the managed entry scheme (MES) to improve patient access to subsidised drugs on the Pharmaceutical Benefits Scheme and enhance the quality of evidence provided to decision makers. The aim of this paper was to critically review the Australian MES experience. We performed a comprehensive review of publicly available Pharmaceutical Benefits Advisory Committee online documents from January 2010 to July 2017. Relevant information on each MES agreement was systematically extracted, including its rationale, the conditions that guided its implementation and its policy outcomes. We identified 11 drugs where an MES was considered. Most of the identified drugs (75%) were antineoplastic agents and the main uncertainty was the overall survival benefit. More than half of the MES proposals were made by sponsors and most of the schemes were considered after previous rejected/deferred submissions for reimbursement. An MES was not established in 8 of 11 drugs (73%) despite the high evidence uncertainty. Nevertheless, six of these eight drugs were listed after the sponsors reduced their prices. Three MESs were established and implemented by Deeds of Agreement. The three cases were concluded and the required data were submitted within the agreed time frames. The need for feasibility and value of an MES should be carefully considered by stakeholders before embarking on such an agreement. It is essential to engage major stakeholders, including patient representatives, in this process. The conditions governing MESs should be clear, transparent and balanced to address the expectations of various stakeholders.

  1. Using p-type PbS Quantum Dots to Quench Photocurrent of Fullerene-Au NP@MoS2 Composite Structure for Ultrasensitive Photoelectrochemical Detection of ATP.

    Science.gov (United States)

    Li, Meng-Jie; Zheng, Ying-Ning; Liang, Wen-Bin; Yuan, Ruo; Chai, Ya-Qin

    2017-12-06

    Ultrasensitive and rapid quantification of the universal energy currency adenosine triphosphate (ATP) is an extremely critical mission in clinical applications. In this work, a "signal-off" photoelectrochemical (PEC) biosensor was designed for ultrasensitive ATP detection based on a fullerene (C 60 )-decorated Au nanoparticle@MoS 2 (C 60 -Au NP@MoS 2 ) composite material as a signal indicator and a p-type PbS quantum dot (QD) as an efficient signal quencher. Modification of wide band gap C 60 with narrow band gap MoS 2 to form an ideal PEC signal indicator was proposed, which could significantly improve photocurrent conversion efficiency, leading to a desirable PEC signal. In the presence of p-type PbS QDs, the PEC signal of n-type C 60 -Au NP@MoS 2 was effectively quenched because p-type PbS QDs could compete with C 60 -Au NP@MoS 2 to consume light energy and electron donor. Besides, the conversion of a limited amount of target ATP into an amplified output PbS QD-labeled short DNA sequence (output S 1 ) was achieved via target-mediated aptazyme cycling amplification strategy, facilitating ultrasensitive ATP detection. The proposed signal-off PEC strategy exhibited a wide linear range from 1.00 × 10 -2 pM to 100 nM with a low detection limit of 3.30 fM. Importantly, this proposed strategy provides a promising platform to detect ATP at ultralow levels and has potential applications, including diagnosis of ATP-related diseases, monitoring of diseases progression and evaluation of prognosis.

  2. Formation of superlattice with aligned plane orientation of colloidal PbS quantum dots

    Science.gov (United States)

    Mukai, Kohki; Fujimoto, Satoshi; Suetsugu, Fumimasa

    2018-04-01

    We investigated a method of forming a perfect quantum dot (QD) superlattice, in which each QD has the same plane orientation, by depositing colloidal PbS QDs with clear facets in solution. QD facets were controlled by adjusting the synthesis temperature. X-ray evaluation showed that the crystal orientations of the film with QDs having clear facets were aligned. The slow deposition promoted this crystal alignment. The red shift of photoluminescence wavelength caused by the film formation was larger with QDs having facets than with spherical QDs, suggesting that the connection of the wave function between QDs was better so that the quantum size effect was further reduced.

  3. Structural, optical and electrical characterization of Mn2+ and Cd2+ doped/co-doped PbS nanocrystals

    International Nuclear Information System (INIS)

    Sakthi Sudar Saravanan, R.; Meena, M.; Pukazhselvan, D.; Mahadevan, C.K.

    2015-01-01

    Highlights: • Mn and Cd doped/codoped nano PbS was synthesized by SMI method. • The observed stress is ∼90% lower, and the strain is only in the order of 10 −6 . • Band gap value can be enhanced from 0.5 eV to 2.025–2.235 eV (±0.012 eV). • Role of two conduction activation barriers was observed. - Abstract: The strain and stress minimized nanoparticles of PbS, Pb 0.95 Mn 0.05 S, Pb 0.95 Cd 0.05 S and Pb 0.90 Mn 0.05 Cd 0.05 S were successfully synthesized using solvothermal microwave irradiation (SMI) method. The quality/performance of the materials was found to be in the series Pb 0.90 Mn 0.05 Cd 0.05 S > Pb 0.95 Cd 0.05 S > Pb 0.95 Mn 0.05 S > PbS. The average crystallite size in the best material Pb 0.90 Mn 0.05 Cd 0.05 S was found to be ∼18 nm where the particles are distributed within the range 20–60 nm. Optical studies reveals the existence of direct band gap in the range of 2.025–2.235 eV (±0.012 eV). This is one of the widest E g values reported for this system. Electrical measurements were performed on compacts of nanoparticles in the temperature range 313–433 K and frequency range 100 Hz–1 MHz. The conductivity profile exhibits two components; in which the activation energy (ΔE) values obtained for the temperature range 373–433 K is almost twice as compared to the ΔE value obtained for 313–373 K. Nonetheless, the conductivity at the higher temperatures was always higher than at the low temperatures and interestingly, the nanoparticles exhibits higher conductivity than their bulk counterpart. The feasible mechanism of conduction is discussed

  4. REMINDER: Saved Leave Scheme (SLS)

    CERN Multimedia

    2003-01-01

    Transfer of leave to saved leave accounts Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'* annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that unused leave of all those taking part in the saved leave scheme at the closure of the leave year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2003 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they ar...

  5. Benefits, risks, and costs of stratospheric geoengineering

    KAUST Repository

    Robock, Alan; Marquardt, Allison; Kravitz, Ben; Stenchikov, Georgiy L.

    2009-01-01

    Injecting sulfate aerosol precursors into the stratosphere has been suggested as a means of geoengineering to cool the planet and reduce global warming. The decision to implement such a scheme would require a comparison of its benefits, dangers

  6. IMPLEMENTATION OF OPEN-SOURCE WEB MAPPING TECHNOLOGIES TO SUPPORT MONITORING OF GOVERNMENTAL SCHEMES

    Directory of Open Access Journals (Sweden)

    B. R. Pulsani

    2015-10-01

    Full Text Available Several schemes are undertaken by the government to uplift social and economic condition of people. The monitoring of these schemes is done through information technology where involvement of Geographic Information System (GIS is lacking. To demonstrate the benefits of thematic mapping as a tool for assisting the officials in making decisions, a web mapping application for three government programs such as Mother and Child Tracking system (MCTS, Telangana State Housing Corporation Limited (TSHCL and Ground Water Quality Mapping (GWQM has been built. Indeed the three applications depicted the distribution of various parameters thematically and helped in identifying the areas with higher and weaker distributions. Based on the three applications, the study tends to find similarities of many government schemes reflecting the nature of thematic mapping and hence deduces to implement this kind of approach for other schemes as well. These applications have been developed using SharpMap Csharp library which is a free and open source mapping library for developing geospatial applications. The study highlights upon the cost benefits of SharpMap and brings out the advantage of this library over proprietary vendors and further discusses its advantages over other open source libraries as well.

  7. Low-Feedback Opportunistic Scheduling Schemes for Wireless Networks with Heterogenous Users

    KAUST Repository

    Rashid, Faraan

    2012-07-01

    Efficient implementation of resource sharing strategies in a multi-user wireless environment can improve the performance of a network significantly. In this thesis we study various scheduling strategies for wireless networks and handle the problem of opportunistically scheduling transmissions using channel aware schemes. First we propose a scheme that can handle users with asymmetric channel conditions and is opportunistic in the sense that it exploits the multi-user diversity of the network. The scheme requires the users to have a priori knowledge of their channel distributions. The associated overhead is limited meaning it offers reduced feedback load, that does not scale with the increasing number of users. The main technique used to shrink the feedback load is the contention based distributed implementation of a splitting algorithm that does not require explicit feedback to the scheduler from every user. The users find the best among themselves, in a distributed manner, while requiring just a ternary broadcast feedback from the scheduler at the end of each mini-slot. In addition, it can also handle fairness constraints in time and throughput to various degrees. Next we propose another opportunistic scheduler that offers most of the benefits of the previously proposed scheme but is more practical because it can also handle heterogenous users whose channel distributions are unknown. This new scheme actually reduces the complexity and is also more robust for changing traffic patterns. Finally we extend both these schemes to the scenario where there are fixed thresholds, this enables us to handle opportunistic scheduling in practical systems that can only transmit over finite number of discrete rates with the additional benefit that full feedback session, even from the selected user, is never required.

  8. When can insurers offer products that dominate delayed old-age pension benefit claiming?

    NARCIS (Netherlands)

    Sanders, L.; De Waegenaere, A.M.B.; Nijman, T.E.

    2013-01-01

    It is common practice for public pension schemes to offer individuals the option to delay benefit claiming until after the normal retirement age, and increase the annual benefit level as a result. Existing literature shows that for non-liquidity constrained individuals, delaying benefit claiming for

  9. Static and dynamic efficiency of white certificate schemes

    International Nuclear Information System (INIS)

    Giraudet, L.G.; Finon, D.

    2011-01-01

    White Certificate Schemes mandate energy companies to promote energy efficiency through flexibility mechanisms, including the trading of energy savings. They can be characterized as a quantity-based, baseline-and-credit system for the diffusion of energy efficient technologies. This paper compares experiences with White Certificate Schemes in Great Britain, Italy and France, in order to identify the basic drivers of each, and ultimately offer an original interpretation as an adaptive instrument, in the sense that it can take different forms in response to specific institutional contexts. A first analysis shows that Schemes perform well in terms of static efficiency, i.e. they are cost-effective and generate net social benefits over the period considered, though with large discrepancies rooted in different technological potentials. Regarding dynamic efficiency, i.e. the ability to induce and sustain technological change over the long haul, market transformation occurred in Great Britain, but was poorly incentivized in Italy and France by inadequate compliance cost recovery rules. Substantial organizational change has occurred in every country, mainly by strengthening vertical relationships between obliged parties and upstream businesses. Overall, the obligation (rather than the market component) drives the early phases of the Schemes. (authors)

  10. Transaction costs of Tradable White Certificate schemes: The Energy Efficiency Commitment as case study

    International Nuclear Information System (INIS)

    Mundaca, Luis

    2007-01-01

    This paper analyses the nature and scale of transaction costs (TCs) borne by obliged parties under a 'Tradable White Certificate' (TWC) scheme. Taking the first phase of the Energy Efficiency Commitment (EEC1) in Great Britain as a case study, several sources of TCs were considered, such as search for information, persuasion of customers, negotiation with business partners, and measurement and verification activities. Information was obtained through interviews and a questionnaire distributed to obliged parties. Results show that the most significant sources of TCs were related to search for information, persuading customers and negotiating with managing agents/contractors to implement energy efficiency measures. Perceived high TCs related to contract negotiation and liability risks slightly reduced the low trading level. The scale of TCs was estimated to be around 10% and 30% of total investments costs for the lighting and insulation segments, respectively. The results indicate that, despite the presence and scale of TCs, the EEC1 scheme generated energy savings that yielded net societal benefits. Estimated financial benefits range from 0.6 to 6 p/kWh for insulation and lighting savings, respectively. When avoided external costs due to electricity savings are included, estimated economic benefits range from 3 to 8 p/kWh. Several lessons from the EEC1 can be drawn for TWC schemes. Among others, it is found that informative policy instruments to raise awareness among end-users are critical if a TWC scheme is to deliver cost-effective energy savings. In all, the nature and scale of TCs under TWC schemes will differ because of a number of endogenous and exogenous determinants

  11. Transaction costs of Tradable White Certificate schemes: The Energy Efficiency Commitment as case study

    Energy Technology Data Exchange (ETDEWEB)

    Mundaca, Luis [International Institute for Industrial Environmental Economics at Lund University, Lund (Sweden)

    2007-08-15

    This paper analyses the nature and scale of transaction costs (TCs) borne by obliged parties under a ''Tradable White Certificate'' (TWC) scheme. Taking the first phase of the Energy Efficiency Commitment (EEC1) in Great Britain as a case study, several sources of TCs were considered, such as search for information, persuasion of customers, negotiation with business partners, and measurement and verification activities. Information was obtained through interviews and a questionnaire distributed to obliged parties. Results show that the most significant sources of TCs were related to search for information, persuading customers and negotiating with managing agents/contractors to implement energy efficiency measures. Perceived high TCs related to contract negotiation and liability risks slightly reduced the low trading level. The scale of TCs was estimated to be around 10% and 30% of total investments costs for the lighting and insulation segments, respectively. The results indicate that, despite the presence and scale of TCs, the EEC1 scheme generated energy savings that yielded net societal benefits. Estimated financial benefits range from 0.6 to 6 p/kWh for insulation and lighting savings, respectively. When avoided external costs due to electricity savings are included, estimated economic benefits range from 3 to 8 p/kWh. Several lessons from the EEC1 can be drawn for TWC schemes. Among others, it is found that informative policy instruments to raise awareness among end-users are critical if a TWC scheme is to deliver cost-effective energy savings. In all, the nature and scale of TCs under TWC schemes will differ because of a number of endogenous and exogenous determinants. (author)

  12. Pension Benefit Insurance and Pension Plan Portfolio Choice

    OpenAIRE

    Thomas Crossley; Mario Jametti

    2008-01-01

    Pension benefit guarantee policies have been introduced in several countries to pro- tect private pension plan members from the loss of income that would occur if a plan was underfunded when the sponsoring firm terminates a plan. Most of these public insurance schemes face financial dificulty and consequently policy reforms are being discussed or implemented. Economic theory suggests that such schemes will face moral hazard and adverse selection problems. In this note we test a specific theor...

  13. A Credit-Based Congestion-Aware Incentive Scheme for DTNs

    Directory of Open Access Journals (Sweden)

    Qingfeng Jiang

    2016-12-01

    Full Text Available In Delay-Tolerant Networks (DTNs, nodes may be selfish and reluctant to expend their precious resources on forwarding messages for others. Therefore, an incentive scheme is necessary to motivate selfish nodes to cooperatively forward messages. However, the current incentive schemes mainly focus on encouraging nodes to participate in message forwarding, without considering the node congestion problem. When many messages are forwarded to the nodes with high connection degree, these nodes will become congested and deliberately discard messages, which will seriously degrade the routing performance and reduce the benefits of other nodes. To address this problem, we propose a credit-based congestion-aware incentive scheme (CBCAIS for DTNs. In CBCAIS, a check and punishment mechanism is proposed to prevent forwarding nodes from deliberately discarding message. In addition, a message acceptance selection mechanism is proposed to allow the nodes to decide whether to accept other messages, according to self congestion degree. The experimental results show that CBCAIS can effectively stimulate selfish nodes to cooperatively forward messages, and achieve a higher message delivery ratio with lower overhead ratio, compared with other schemes.

  14. Magneto-optical controlled transmittance alteration of PbS quantum dots by moderately applied magnetic fields at room temperature

    International Nuclear Information System (INIS)

    Singh, Akhilesh K.; Barik, Puspendu; Ullrich, Bruno

    2014-01-01

    We observed changes of the transmitted monochromatic light passing through a colloidal PbS quantum dot film on glass owing to an applied moderate (smaller than 1 T) magnetic field under ambient conditions. The observed alterations show a square dependence on the magnetic field increase that cannot be achieved with bulk semiconductors. The findings point to so far not recognized application potentials of quantum dots

  15. HEALTH INSURANCE RULES OF THE CERN HEALTH INSURANCE SCHEME

    CERN Multimedia

    Division HR

    2000-01-01

    A new document which groups together the general principles, the contributions, benefits, reimbursement procedures and other information making up the Rules of the CERN Health Insurance Scheme has been established. It was approved by the Director-General on 7th July 2000 and is being distributed to all contributing members of the Scheme. It has been dispatched by internal mail to members of the personnel and by postal mail to pensioners. These Rules will enter into force on 1st September 2000. Please make sure that you have received your copy. Should this not be the case, an additional copy may be obtained by telephoning 78003

  16. Health Insurance Rules of the CERN Health Insurance scheme

    CERN Multimedia

    Division HR

    2000-01-01

    A new document which groups together the general principles, the contributions, benefits, reimbursement procedures and other information making up the Rules of the CERN Health Insurance Scheme has been established. It was approved by the Director-General on 7th July 2000 and is being distributed to all contributing members of the Scheme. It has been dispatched by internal mail to members of the personnel and by postal mail to pensioners. These Rules will enter into force on 1st September 2000. Please make sure that you have received your copy. Should this not be the case, an additional copy may be obtained by telephoning 78003.

  17. Design of a QA method to characterize submillimeter-sized PBS beam properties using a 2D ionization chamber array

    Science.gov (United States)

    Lin, Yuting; Bentefour, Hassan; Flanz, Jacob; Kooy, Hanne; Clasie, Benjamin

    2018-05-01

    Pencil beam scanning (PBS) periodic quality assurance (QA) programs ensure the beam delivered to patients is within technical specifications. Two critical specifications for PBS delivery are the beam width and position. The aim of this study is to investigate whether a 2D ionization chamber array, such as the MatriXX detector (IBA Dosimetry, Schwarzenbruck, Germany), can be used to characterize submillimeter-sized PBS beam properties. The motivation is to use standard equipment, which may have pixel spacing coarser than the pencil beam size, and simplify QA workflow. The MatriXX pixels are cylindrical in shape with 4.5 mm diameter and are spaced 7.62 mm from center to center. Two major effects limit the ability of using the MatriXX to measure the spot position and width accurately. The first effect is that too few pixels sample the Gaussian shaped pencil beam profile and the second effect is volume averaging of the Gaussian profile over the pixel sensitive volumes. We designed a method that overcomes both limitations and hence enables the use of the MatriXX to characterize sub-millimeter-sized PBS beam properties. This method uses a cross-like irradiation pattern that is designed to increase the number of sampling data points and a modified Gaussian fitting technique to correct for volume averaging effects. Detector signals were calculated in this study and random noise and setup errors were added to simulate measured data. With the techniques developed in this work, the MatriXX detector can be used to characterize the position and width of sub-millimeter, σ  =  0.7 mm, sized pencil beams with uncertainty better than 3% relative to σ. With the irradiation only covering 60% of the MatriXX, the position and width of σ  =  0.9 mm sized pencil beams can be determined with uncertainty better than 3% relative to σ. If one were to not use a cross-like irradiation pattern, then the position and width of σ  =  3.6 mm sized pencil beams

  18. On Converting Secret Sharing Scheme to Visual Secret Sharing Scheme

    Directory of Open Access Journals (Sweden)

    Wang Daoshun

    2010-01-01

    Full Text Available Abstract Traditional Secret Sharing (SS schemes reconstruct secret exactly the same as the original one but involve complex computation. Visual Secret Sharing (VSS schemes decode the secret without computation, but each share is m times as big as the original and the quality of the reconstructed secret image is reduced. Probabilistic visual secret sharing (Prob.VSS schemes for a binary image use only one subpixel to share the secret image; however the probability of white pixels in a white area is higher than that in a black area in the reconstructed secret image. SS schemes, VSS schemes, and Prob. VSS schemes have various construction methods and advantages. This paper first presents an approach to convert (transform a -SS scheme to a -VSS scheme for greyscale images. The generation of the shadow images (shares is based on Boolean XOR operation. The secret image can be reconstructed directly by performing Boolean OR operation, as in most conventional VSS schemes. Its pixel expansion is significantly smaller than that of VSS schemes. The quality of the reconstructed images, measured by average contrast, is the same as VSS schemes. Then a novel matrix-concatenation approach is used to extend the greyscale -SS scheme to a more general case of greyscale -VSS scheme.

  19. Multi-Hierarchical Gray Correlation Analysis Applied in the Selection of Green Building Design Scheme

    Science.gov (United States)

    Wang, Li; Li, Chuanghong

    2018-02-01

    As a sustainable form of ecological structure, green building is widespread concerned and advocated in society increasingly nowadays. In the survey and design phase of preliminary project construction, carrying out the evaluation and selection of green building design scheme, which is in accordance with the scientific and reasonable evaluation index system, can improve the ecological benefits of green building projects largely and effectively. Based on the new Green Building Evaluation Standard which came into effect on January 1, 2015, the evaluation index system of green building design scheme is constructed taking into account the evaluation contents related to the green building design scheme. We organized experts who are experienced in construction scheme optimization to mark and determine the weight of each evaluation index through the AHP method. The correlation degree was calculated between each evaluation scheme and ideal scheme by using multilevel gray relational analysis model and then the optimal scheme was determined. The feasibility and practicability of the evaluation method are verified by introducing examples.

  20. Quadrature Decomposition by Phase Conjugation and Projection in a Polarizing Beam Splitter

    DEFF Research Database (Denmark)

    Kjøller, Niels-Kristian; Galili, Michael; Dalgaard, Kjeld

    2014-01-01

    We propose simultaneous decomposition of the two quadratures of an optical data signal to different outputs of a PBS by degenerate four-wave mixing with orthogonal pumps. The scheme is demonstrated by QPSK to 2×BPSK modulation format conversion with BER<10−9.......We propose simultaneous decomposition of the two quadratures of an optical data signal to different outputs of a PBS by degenerate four-wave mixing with orthogonal pumps. The scheme is demonstrated by QPSK to 2×BPSK modulation format conversion with BER−9....

  1. Improving charge transport in PbS quantum Dot to Al:ZnO layer by changing the size of Quantum dots in hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Mehrabian, Masood [Maragheh Univ. (Iran, Islamic Republic of). Faculty of Basic Science; Abdollahian, Parinaz [Maragheh Univ. (Iran, Islamic Republic of). Dept. of Materials Engineering

    2016-07-01

    PbS Quantum dots and P3HT are promising materials for photovoltaic applications due to their absorption in the NIR and visible region, respectively. Our previous experimental work showed that doping Al to ZnO lattice (Al:ZnO) could efficiently improve the cell performance. In this article, hybrid solar cells containing of two active areas with ITO/Al:ZnO/PbS QDs/P3HT and PCBM/Ag structure were fabricated and the effect of PbS QD size on photovoltaic properties was investigated. Optimised solar cell showed maximum power conversion efficiency of 2.45 % with short-circuit current of 9.36 mA/cm{sup 2} and open-circuit voltage of 0.59 V under 1 sun illumination (AM1.5).

  2. Facilitators and hindrances in the experiences of Ugandans with and without disabilities when seeking access to microcredit schemes.

    Science.gov (United States)

    Cramm, Jane Murray; Paauwe, Marthe; Finkenflügel, Harry

    2012-01-01

    This study aimed to identify facilitators and hindrances in the experiences of Ugandans with and without disabilities when seeking access to microcredit schemes. Thirty-five statements were presented to 80 people, 50 of whom were disabled. Q-methodology was used to identify factors influencing access to microcredit schemes. Running a business independently was solely identified by people with disabilities (PWD) as an important facilitator in accessing microcredit schemes, while relying on business skills was largely mentioned by people without disabilities. The disabled identified family-related items to be inhibiting factors. Having a group loan was ranked negatively by the disabled and ambivalently by the non-disabled. PWD experience different facilitators and barriers to access microcredit schemes compared to the non-disabled. PWD prefer individual loans and believe they can more successfully run a business on their own, instead of relying on family or having a group loan. Furthermore, they would benefit from microcredit schemes that take into account disability-specific circumstances. These are important findings to increase access to microcredit schemes and to let PWD benefit to the same extend from these programmes than do their non-disabled peers.

  3. Understanding the types of fraud in claims to South African medical schemes.

    Science.gov (United States)

    Legotlo, T G; Mutezo, A

    2018-03-28

    Medical schemes play a significant role in funding private healthcare in South Africa (SA). However, the sector is negatively affected by the high rate of fraudulent claims. To identify the types of fraudulent activities committed in SA medical scheme claims. A cross-sectional qualitative study was conducted, adopting a case study strategy. A sample of 15 employees was purposively selected from a single medical scheme administration company in SA. Semi-structured interviews were conducted to collect data from study participants. A thematic analysis of the data was done using ATLAS.ti software (ATLAS.ti Scientific Software Development, Germany). The study population comprised the 17 companies that administer medical schemes in SA. Data were collected from 15 study participants, who were selected from the medical scheme administrator chosen as a case study. The study found that medical schemes were defrauded in numerous ways. The perpetrators of this type of fraud include healthcare service providers, medical scheme members, employees, brokers and syndicates. Medical schemes are mostly defrauded by the submission of false claims by service providers and syndicates. Fraud committed by medical scheme members encompasses the sharing of medical scheme benefits with non-members (card farming) and non-disclosure of pre-existing conditions at the application stage. The study concluded that perpetrators of fraud have found several ways of defrauding SA medical schemes regarding claims. Understanding and identifying the types of fraud events facing medical schemes is the initial step towards establishing methods to mitigate this risk. Future studies should examine strategies to manage fraudulent medical scheme claims.

  4. Optimization of rhamnolipid production from Pseudomonas aeruginosa PBS towards application for microbial enhanced oil recovery.

    Science.gov (United States)

    Sharma, Rajni; Singh, Jagdish; Verma, Neelam

    2018-01-01

    The present work reveals the potential of biosurfactant producing P. aeruginosa PBS for microbial enhanced oil recovery (MEOR). The biosurfactant production medium and culture conditions were optimized using response surface methodology. The optimization of media components and process parameters was consecutively executed in two sets of experimental runs designed by central composite rotatable design (CCRD). The maximum biosurfactant yield was attained with 2% fresh inoculum of P. aeruginosa PBS in minimal salt medium (pH 7), possessing 2.17% sodium citrate as C-source and 0.5% yeast extract as N-source, after 48 h upon incubation at 30 °C/150 rpm. Under optimum conditions, biosurfactant yield was increased more than threefold and turned out to be 2.65 g/L as compared to 0.82 g/L under previous conditions. The biosurfactant was characterized as a glycolipid comprising of four rhamnolipid homologs (RhaRhaC 10 C 10 , RhaRhaC 8 C 10 , RhaRhaC 12 C 10 /RhaRhaC 10 C 12 , RhaC 10 C 10 ) by thin layer chromatography, fourier transform infrared spectroscopy, nuclear magnetic resonance and mass spectrometry. The produced biosurfactant was highly efficient for oil recovery application showing extreme reduction in surface tension of medium (71.80 to 23.76 mN/m), immense hydrocarbons emulsification capacity (50-60%) and greater stability at wide range of temperature (4-100 °C) and pH (4-10) along with an excellent (56.18 ± 1.59%) additional oil recovery in sand-pack column lab test.

  5. A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

    OpenAIRE

    Zhu, Jingwei; Chen, Michael Z. Q.; Du, Baozhu

    2014-01-01

    Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devic...

  6. How Readers and Advertisers Benefit from Local Newspaper Competition.

    Science.gov (United States)

    Everett, Shu-Ling Chen; Everett, Stephen E.

    1989-01-01

    Explores relations among three competitive schemes with respect to newspapers' price structures, including advertising rates and prices to consumers. Finds that readers get some benefit from greater competition, but that advertisers do not. (MM)

  7. The Australian model of immunization advice and vaccine funding.

    Science.gov (United States)

    Nolan, Terry M

    2010-04-19

    The Australian Government has implemented new arrangements for public funding of vaccines over the past 5 years. By utilising the standard Pharmaceutical Benefits Advisory Committee (PBAC) application process, whether for funding under the National Immunisation Program Schedule (NIP) or under the Pharmaceutical Benefits Scheme (PBS), a predictable and transparent process for vaccine funding recommendations has been established. This process uses the high-level technical resources available through the Australian Technical Advisory Group on Immunisation (ATAGI) to ensure that both vaccine manufacturers and the PBAC are optimally informed about all relevant aspects of population benefits and delivery of vaccines. ATAGI has a long-standing and mutually beneficial dialogue with State and Territory Governments, providers, and vaccine manufacturers to ensure that pipeline awareness, supply issues, and all relevant scientific and clinical details are well understood. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. CS-DRM: A Cloud-Based SIM DRM Scheme for Mobile Internet

    Directory of Open Access Journals (Sweden)

    Liu Zhang

    2011-01-01

    Full Text Available With the rapid development and growth of the mobile industry, a considerable amount of mobile applications and services are available, which involve Internet scale data collections. Meanwhile, it has a tremendous impact on digital content providers as well as the mobile industry that a large number of digital content have been pirated and illegally distributed. Digital Rights Management (DRM aims at protecting digital contents from being abused through regulating their usage. Unfortunately, to the best of our knowledge, fewer of these DRM schemes are concerned with the cost of the servers in a DRM system when the number of users scales up, and consider benefits of content providers who can be seen as tenants of a content server. In this paper, we propose CS-DRM, a cloud-based SIM DRM scheme, for the mobile Internet. The SIM card is introduced into CS-DRM to both reduce the cost and provide higher security. Also, the characteristics of cloud computing enable CS-DRM to bring benefits for content providers, and well satisfy the performance requirements with low cost when the number of users increases significantly. Furthermore, we have implemented a prototype of our DRM scheme, which demonstrates that CS-DRM is efficient, secure, and practicable.

  9. Numerical study of a hybrid jet impingement/micro-channel cooling scheme

    International Nuclear Information System (INIS)

    Barrau, Jérôme; Omri, Mohammed; Chemisana, Daniel; Rosell, Joan; Ibañez, Manel; Tadrist, Lounes

    2012-01-01

    A new hybrid jet impingement/micro-channel cooling scheme is studied numerically for use in high-heat-flux thermal management of electronic and power devices. The device is developed with the objective of improving the temperature uniformity of the cooled object. A numerical model based on the k–ω SST turbulent model is developed and validated experimentally. This model is used to carry out a parametrical characterization of the heat sink. The study shows that variations in key parameters of jet impingement and micro-channel technologies allow for the cooling scheme to obtain a wide range of temperature profiles for the cooled object. - Highlights: ► A new hybrid cooling scheme is numerically studied. ► The cooling scheme combines the benefits of jet impingement and micro-channel flows. ► The numerical model is validated by comparison with experimental results. ► The temperature distribution can be adapted to the needs of the cooled system.

  10. Mechanical Properties in a Bamboo Fiber/PBS Biodegradable Composite

    Science.gov (United States)

    Ogihara, Shinji; Okada, Akihisa; Kobayashi, Satoshi

    In recent years, biodegradable plastics which have low effect on environment have been developed. However, many of them have lower mechanical properties than conventional engineering plastics. Reinforcing them with a natural fiber is one of reinforcing methods without a loss of their biodegradability. In the present study, we use a bamboo fiber as the reinforcement and polybutylenesuccinate (PBS) as the matrix. We fabricate long fiber unidirectional composites and cross-ply laminate with different fiber weight fractions (10, 20, 30, 40 and 50wt%). We conduct tensile tests to evaluate the mechanical properties of these composites. In addition, we measure bamboo fiber strength distribution. We discuss the experimentally-obtained properties based on the mechanical properties of the constituent materials. Young's modulus and tensile strength in unidirectional composite and cross-ply laminate increase with increasing fiber weight fraction. However, the strain at fracture showed decreasing tendency. Young's modulus in fiber and fiber transverse directions are predictable by the rules of mixture. Tensile strength in fiber direction is lower than Curtin's prediction of strength which considers distribution of fiber strength. Young's modulus in cross-ply laminate is predictable by the laminate theory. However, analytical prediction of Poisson's ratio in cross-ply laminate by the laminate theory is lower than the experimental results.

  11. Colloidal PbS nanocrystals integrated to Si-based photonics for applications at telecom wavelengths

    Science.gov (United States)

    Humer, M.; Guider, R.; Jantsch, W.; Fromherz, T.

    2013-05-01

    In the last decade, Si based photonics has made major advances in terms of design, fabrication, and device implementation. But due to Silicon's indirect bandgap, it still remains a challenge to create efficient Si-based light emitting devices. In order to overcome this problem, an approach is to develop hybrid systems integrating light-emitting materials into Si. A promising class of materials for this purpose is the class of semiconducting nanocrystal quantum dots (NCs) that are synthesized by colloidal chemistry. As their absorption and emission wavelength depends on the dot size, which can easily be controlled during synthesis, they are extremely attractive as building blocks for nanophotonic applications. For applications in telecom wavelength, Lead chalcogenide colloidal NCs are optimum materials due to their unique optical, electronic and nonlinear properties. In this work, we experimentally demonstrate the integration of PbS nanocrystals into Si-based photonic structures like slot waveguides and ring resonators as optically pumped emitters for room temperature applications. In order to create such hybrid structures, the NCs were dissolved into polymer resists and drop cast on top of the device. Upon optical pumping, intense photoluminescence emission from the resonating modes is recorded at the output of the waveguide with transmission quality factors up to 14000. The polymer host material was investigated with respect to its ability to stabilize the NC's photoluminescence emission against degradation under ambient conditions. The waveguide-ring coupling efficiency was also investigated as function of the NCs concentrations blended into the polymer matrix. The integration of colloidal quantum dots into Silicon photonic structures as demonstrated in this work is a very versatile technique and thus opens a large range of applications utilizing the linear and nonlinear optical properties of PbS NCs at telecom wavelengths.

  12. The social security scheme in Thailand: what lessons can be drawn?

    Science.gov (United States)

    Tangcharoensathien, V; Supachutikul, A; Lertiendumrong, J

    1999-04-01

    The Social Security Scheme was launched in 1990, covering formal sector private employees for non-work related sickness, maternity and invalidity including cash benefits and funeral grants. The scheme is financed by tripartite contributions from government, employers and employees, each of 1.5% of payroll (total of 4.5%). The scheme decided to pay health care providers, whether public or private, on a flat rate capitation basis to cover both ambulatory and inpatient care. Registration of the insured with a contractor hospital was a necessary consequence of the chosen capitation payment system. The aim of this paper is to review the operation of the scheme, and to explore the implications of capitation payment and registration for utilisation levels and provider behaviour. A key weakness of the scheme's design is suggested to be the initial decision to give employers not employees the responsibility for choosing the registered hospitals. This was done for administrative reasons, but it contributed to low levels of use of the contractor hospitals. In addition, low levels of use were also probably the result of the potential for cream skimming, cost shifting from inpatient to ambulatory care and under-provision of patient care, though since monitoring mechanisms by the Social Security Office were weak, these effects are difficult to detect conclusively. Mechanisms to improve utilisation levels were gradually introduced, such as employee choice of registered hospitals and the formation of sub-contractor networks to improve access to care. A beneficial effect of the capitation payment system was that the Social Security Fund generated substantial reserves and expenditures on sickness benefits were well stabilised. The paper ends by recommending that future policy amendments should be guided by research and empirical findings and that tougher monitoring and enforcement of quality of care standards are required.

  13. Study of band gap and determination of size of PbS quantum dots synthesized by colloidal solution

    Directory of Open Access Journals (Sweden)

    M. S. Ghamsari

    2005-03-01

    Full Text Available   PbS semiconductor non-crystals have been synthesized in order to study the modification of their electronic structures and optical properties in relation to their size. The synthesis has been carried out by using the techniques of colloidal chemistry. Strong quantum confinement behavior has been observed based on the analysis of optical spectra of these particles. The average particle size approximated by x-ray line width and hyperbolic band model calculation. Heterogeneous broadening of optical spectrum is studied finally.

  14. The benefits of paid maternity leave for mothers' post-partum health and wellbeing: Evidence from an Australian evaluation.

    Science.gov (United States)

    Hewitt, Belinda; Strazdins, Lyndall; Martin, Bill

    2017-06-01

    This paper investigates the health effects of the introduction of a near universal paid parental leave (PPL) scheme in Australia, representing a natural social policy experiment. Along with gender equity and workforce engagement, a goal of the scheme (18 weeks leave at the minimum wage rate) was to enhance the health and wellbeing of mothers and babies. Although there is evidence that leave, especially paid leave, can benefit mothers' health post-partum, the potential health benefits of implementing a nationwide scheme have rarely been investigated. The data come from two cross-sectional surveys of mothers (matched on their eligibility for paid parental leave), 2347 mother's surveyed pre-PPL and 3268 post-PPL. We investigated the scheme's health benefits for mothers, and the extent this varied by pre-birth employment conditions and job characteristics. Overall, we observed better mental and physical health among mothers after the introduction of PPL, although the effects were small. Post-PPL mothers on casual (insecure) contracts before birth had significantly better mental health than their pre-PPL counterparts, suggesting that the scheme delivered health benefits to mothers who were relatively disadvantaged. However, mothers on permanent contracts and in managerial or professional occupations also had significantly better mental and physical health in the post-PPL group. These mothers were more likely to combine the Government sponsored leave with additional, paid, employer benefits, enabling a longer paid leave package post-partum. Overall, the study provides evidence that introducing paid maternity leave universally delivers health benefits to mothers. However the modest 18 week PPL provision did little to redress health inequalities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. What constitutes a benefit by virtue of section 186(2) of the labour ...

    African Journals Online (AJOL)

    The court found that the early retirement scheme was a benefit, although the employee at that stage did not have a contractual entitlement to the benefit and that the benefit was subject to the employer's discretion. What becomes clear from this case is that the unfair labour practice jurisdiction cannot be used to assert an ...

  16. Costs and economic consequences of a help-at-home scheme for older people in England.

    Science.gov (United States)

    Bauer, Annette; Knapp, Martin; Wistow, Gerald; Perkins, Margaret; King, Derek; Iemmi, Valentina

    2017-03-01

    Solutions to support older people to live independently and reduce the cost of an ageing population are high on the political agenda of most developed countries. Help-at-home schemes offer a mix of community support with the aim to address a range of well-being needs. However, not much is currently known about the costs, outcomes and economic consequences of such schemes. Understanding their impact on individuals' well-being and the economic consequences for local and central government can contribute to decisions about sustainable long-term care financing. This article presents results from a mixed-methods study of a voluntary sector-provided help-at-home scheme in England for people of 55 years and older. The study followed a participatory approach, which involved staff and volunteers. Data were collected during 2012 and 2013. Social care-related quality of life was measured with the Adult Social Care Outcomes Toolkit for 24 service users (59% response rate) when they started using the scheme and 4-6 months later. A customised questionnaire that captured resource use and well-being information was sent to 1064 service users (63% response rate). The same tool was used in assessment with service users who started using the scheme between November 2012 and April 2013 (100% response rate). Costs of the scheme were established from local budget and activity data. The scheme was likely to achieve a mean net benefit of £1568 per person from a local government and National Health Service (NHS) perspective and £3766 from the perspective of the individual. An expenditure of £2851 per person accrued to central government for the additional redistribution of benefit payments to older people. This article highlights the potential contribution of voluntary sector-run help-at-home schemes to an affordable welfare system for ageing societies. © 2016 John Wiley & Sons Ltd.

  17. Indian community health insurance schemes provide partial protection against catastrophic health expenditure

    Directory of Open Access Journals (Sweden)

    Ranson Kent

    2007-03-01

    Full Text Available Abstract Background More than 72% of health expenditure in India is financed by individual households at the time of illness through out-of-pocket payments. This is a highly regressive way of financing health care and sometimes leads to impoverishment. Health insurance is recommended as a measure to protect households from such catastrophic health expenditure (CHE. We studied two Indian community health insurance (CHI schemes, ACCORD and SEWA, to determine whether insured households are protected from CHE. Methods ACCORD provides health insurance cover for the indigenous population, living in Gudalur, Tamil Nadu. SEWA provides insurance cover for self employed women in the state of Gujarat. Both cover hospitalisation expenses, but only upto a maximum limit of US$23 and US$45, respectively. We reviewed the insurance claims registers in both schemes and identified patients who were hospitalised during the period 01/04/2003 to 31/03/2004. Details of their diagnoses, places and costs of treatment and self-reported annual incomes were obtained. There is no single definition of CHE and none of these have been validated. For this research, we used the following definition; "annual hospital expenditure greater than 10% of annual income," to identify those who experienced CHE. Results There were a total of 683 and 3152 hospital admissions at ACCORD and SEWA, respectively. In the absence of the CHI scheme, all of the patients at ACCORD and SEWA would have had to pay OOP for their hospitalisation. With the CHI scheme, 67% and 34% of patients did not have to make any out-of-pocket (OOP payment for their hospital expenses at ACCORD and SEWA, respectively. Both CHI schemes halved the number of households that would have experienced CHE by covering hospital costs. However, despite this, 4% and 23% of households with admissions still experienced CHE at ACCORD and SEWA, respectively. This was related to the following conditions: low annual income, benefit

  18. Optimal Tradable Credits Scheme and Congestion Pricing with the Efficiency Analysis to Congestion

    Directory of Open Access Journals (Sweden)

    Ge Gao

    2015-01-01

    Full Text Available We allow for three traffic scenarios: the tradable credits scheme, congestion pricing, and no traffic measure. The utility functions of different modes (car, bus, and bicycle are developed by considering the income’s impact on travelers’ behaviors. Their purpose is to analyze the demand distribution of different modes. A social optimization model is built aiming at maximizing the social welfare. The optimal tradable credits scheme (distribution of credits, credits charging, and the credit price, congestion pricing fees, bus frequency, and bus fare are obtained by solving the model. Mode choice behavior under the tradable credits scheme is also studied. Numerical examples are presented to demonstrate the model’s availability and explore the effects of the three schemes on traffic system’s performance. Results show congestion pricing would earn more social welfare than the other traffic measures. However, tradable credits scheme will give travelers more consumer surplus than congestion pricing. Travelers’ consumer surplus with congestion pricing is the minimum, which injures the travelers’ benefits. Tradable credits scheme is considered the best scenario by comparing the three scenarios’ efficiency.

  19. An empirical comparison of alternative schemes for combining electricity spot price forecasts

    International Nuclear Information System (INIS)

    Nowotarski, Jakub; Raviv, Eran; Trück, Stefan; Weron, Rafał

    2014-01-01

    In this comprehensive empirical study we critically evaluate the use of forecast averaging in the context of electricity prices. We apply seven averaging and one selection scheme and perform a backtesting analysis on day-ahead electricity prices in three major European and US markets. Our findings support the additional benefit of combining forecasts of individual methods for deriving more accurate predictions, however, the performance is not uniform across the considered markets and periods. In particular, equally weighted pooling of forecasts emerges as a simple, yet powerful technique compared with other schemes that rely on estimated combination weights, but only when there is no individual predictor that consistently outperforms its competitors. Constrained least squares regression (CLS) offers a balance between robustness against such well performing individual methods and relatively accurate forecasts, on average better than those of the individual predictors. Finally, some popular forecast averaging schemes – like ordinary least squares regression (OLS) and Bayesian Model Averaging (BMA) – turn out to be unsuitable for predicting day-ahead electricity prices. - Highlights: • So far the most extensive study on combining forecasts for electricity spot prices • 12 stochastic models, 8 forecast combination schemes and 3 markets considered • Our findings support the additional benefit of combining forecasts for deriving more accurate predictions • Methods that allow for unconstrained weights, such as OLS averaging, should be avoided • We recommend a backtesting exercise to identify the preferred forecast averaging method for the data at hand

  20. A study of lateral fall-off (penumbra) optimisation for pencil beam scanning (PBS) proton therapy

    Science.gov (United States)

    Winterhalter, C.; Lomax, A.; Oxley, D.; Weber, D. C.; Safai, S.

    2018-01-01

    The lateral fall-off is crucial for sparing organs at risk in proton therapy. It is therefore of high importance to minimize the penumbra for pencil beam scanning (PBS). Three optimisation approaches are investigated: edge-collimated uniformly weighted spots (collimation), pencil beam optimisation of uncollimated pencil beams (edge-enhancement) and the optimisation of edge collimated pencil beams (collimated edge-enhancement). To deliver energies below 70 MeV, these strategies are evaluated in combination with the following pre-absorber methods: field specific fixed thickness pre-absorption (fixed), range specific, fixed thickness pre-absorption (automatic) and range specific, variable thickness pre-absorption (variable). All techniques are evaluated by Monte Carlo simulated square fields in a water tank. For a typical air gap of 10 cm, without pre-absorber collimation reduces the penumbra only for water equivalent ranges between 4-11 cm by up to 2.2 mm. The sharpest lateral fall-off is achieved through collimated edge-enhancement, which lowers the penumbra down to 2.8 mm. When using a pre-absorber, the sharpest fall-offs are obtained when combining collimated edge-enhancement with a variable pre-absorber. For edge-enhancement and large air gaps, it is crucial to minimize the amount of material in the beam. For small air gaps however, the superior phase space of higher energetic beams can be employed when more material is used. In conclusion, collimated edge-enhancement combined with the variable pre-absorber is the recommended setting to minimize the lateral penumbra for PBS. Without collimator, it would be favourable to use a variable pre-absorber for large air gaps and an automatic pre-absorber for small air gaps.

  1. Quantitative atom column position analysis at the incommensurate interfaces of a (PbS)1.14NbS2 misfit layered compound with aberration-corrected HRTEM

    International Nuclear Information System (INIS)

    Garbrecht, M.; Spiecker, E.; Tillmann, K.; Jaeger, W.

    2011-01-01

    Aberration-corrected HRTEM is applied to explore the potential of NCSI contrast imaging to quantitatively analyse the complex atomic structure of misfit layered compounds and their incommensurate interfaces. Using the (PbS) 1.14 NbS 2 misfit layered compound as a model system it is shown that atom column position analyses at the incommensurate interfaces can be performed with precisions reaching a statistical accuracy of ±6 pm. The procedure adopted for these studies compares experimental images taken from compound regions free of defects and interface modulations with a structure model derived from XRD experiments and with multi-slice image simulations for the corresponding NCSI contrast conditions used. The high precision achievable in such experiments is confirmed by a detailed quantitative analysis of the atom column positions at the incommensurate interfaces, proving a tetragonal distortion of the monochalcogenide sublattice. -- Research Highlights: → Quantitative aberration-corrected HRTEM analysis of atomic column positions in (PbS) 1.14 NbS 2 misfit layered compound reveals tetragonal distortion of the PbS subsystem. → Detailed comparison of multi-slice simulations with the experimental NCSI contrast condition imaging results lead to a high precision (better than 10 pm) for determining the positions of atoms. → Precision in gaining information of local structure at atomic scale is demonstrated, which may not be accessible by means of X-ray and neutron diffraction analysis.

  2. Development of a sustainability reporting scheme for biofuels: A UK case study

    International Nuclear Information System (INIS)

    Chalmers, Jessica; Archer, Greg

    2011-01-01

    In 2008, the UK launched the first regulatory sustainability reporting scheme for biofuels. The development of the scheme, managed by the Low Carbon Vehicle Partnership for the Department for Transport, involved extensive stakeholder engagement. The scheme has significantly increased understanding by policy-makers, the biofuels industry and its supply chains on how to monitor and manage the sustainability risks of biofuels and increase their greenhouse-gas benefits. It is providing a practical model for similar developments globally. To receive certificates in order to meet volume obligations under the Renewable Transport Fuel Obligation (RTFO), suppliers must provide a monthly carbon and sustainability report on individual batches of renewable fuels they supply into the UK. The Renewable Fuels Agency produces aggregate monthly reports of overall performance and quarterly updates of individual supplier performance. This scheme is an important first step to assist the biofuels industry to demonstrate its environmental credentials and justify the subsidies received. The paper provides a case study of the development of the scheme, its initial outcomes and outstanding challenges.

  3. Cell Load Balancing Schemes for Uncoordinated Heterogeneous Deployment

    DEFF Research Database (Denmark)

    Mihaylov, Mihail; Mihovska, Albena D.; Poulkov, Vladimir

    2013-01-01

    This paper proposes an energy consumption improvement algorithm based on a coefficient determining the reliability of offloading users to a new base station (BS) regarding the additional power needed for them to be compensated during an offload from pico BS (PBS) to macro BS (MBS) in uncoordinate...

  4. Assessing the quality of proton PBS treatment delivery using machine log files: comprehensive analysis of clinical treatments delivered at PSI Gantry 2

    International Nuclear Information System (INIS)

    Scandurra, D; Albertini, F; Van der Meer, R; Meier, G; Weber, D C; Bolsi, A; Lomax, A

    2016-01-01

    Pencil beam scanning (PBS) proton therapy requires the delivery of many thousand proton beams, each modulated for position, energy and monitor units, to provide a highly conformal patient treatment. The quality of the treatment is dependent on the delivery accuracy of each beam and at each fraction. In this work we describe the use of treatment log files, which are a record of the machine parameters for a given field delivery on a given fraction, to investigate the integrity of treatment delivery compared to the nominal planned dose. The dosimetry-relevant log file parameters are used to reconstruct the 3D dose distribution on the patient anatomy, using a TPS-independent dose calculation system. The analysis was performed for patients treated at Paul Scherrer Institute on Gantry 2, both for individual fields and per series (or plan), and delivery quality was assessed by determining the percentage of voxels in the log file dose distribution within  +/−  1% of the nominal dose. It was seen that, for all series delivered, the mean pass rate is 96.4%. Furthermore, this work establishes a correlation between the delivery quality of a field and the beam position accuracy. This correlation is evident for all delivered fields regardless of individual patient or plan characteristics. We have also detailed further usefulness of log file analysis within our clinical workflow. In summary, we have highlighted that the integrity of PBS treatment delivery is dependent on daily machine performance and is specifically highly correlated with the accuracy of beam position. We believe this information will be useful for driving machine performance improvements in the PBS field. (paper)

  5. Global Mechanisms for Sustaining and Enhancing PES Schemes

    OpenAIRE

    Farley, Josh; Aquino, Andre; Daniels, Amy; Moulaert, Azur; Lee, Dan; Krause, Abby

    2010-01-01

    An international payment for ecosystem service (IPES) schemes may be one of the only mechanisms available to stimulate the provision of vital non-marketed ecosystem services at the global level, as those nations that benefit from global ecosystem services (GES) cannot readily force other sovereign nations to provide them. Currently, international trade offers trillions of dollars in incentives for countries to convert natural capital into marketable goods and services, and few payments to ent...

  6. Linking renewable energy CDM projects and TGC schemes: An analysis of different options

    International Nuclear Information System (INIS)

    Del Rio, Pablo

    2006-01-01

    Renewable energy CDM (RE-CDM) projects encourage cost-effective GHG mitigation and enhanced sustainable development opportunities for the host countries. CERs from CDM projects include the value of the former benefits (i.e., 'climate change benefits'), whereas the second can be given value through the issuing and trading of tradable green certificates (TGCs). Countries could agree to trade these TGCs, leading to additional revenues for the investors in renewable energy projects and, therefore, further encouraging the deployment of CDM projects, currently facing significant barriers. However, the design of a combination of CDM projects and TGC schemes raises several conflicting issues and leads to trade-offs. This paper analyses these issues, identifies the alternatives that may exist to link TGC schemes with RE-CDM projects and analyses the impacts of those options on different variables and actors

  7. Linking renewable energy CDM projects and TGC schemes: An analysis of different options

    Energy Technology Data Exchange (ETDEWEB)

    Del Rio, Pablo [Department of Economics and Business, Facultad de Ciencias Juridicas y Sociales, Universidad de Castilla-La Mancha, C/ Cobertizo de S. Pedro Martir s/n., Toledo-45071 (Spain)]. E-mail: pablo.rio@uclm.es

    2006-11-15

    Renewable energy CDM (RE-CDM) projects encourage cost-effective GHG mitigation and enhanced sustainable development opportunities for the host countries. CERs from CDM projects include the value of the former benefits (i.e., 'climate change benefits'), whereas the second can be given value through the issuing and trading of tradable green certificates (TGCs). Countries could agree to trade these TGCs, leading to additional revenues for the investors in renewable energy projects and, therefore, further encouraging the deployment of CDM projects, currently facing significant barriers. However, the design of a combination of CDM projects and TGC schemes raises several conflicting issues and leads to trade-offs. This paper analyses these issues, identifies the alternatives that may exist to link TGC schemes with RE-CDM projects and analyses the impacts of those options on different variables and actors.

  8. Heterojunction PbS nanocrystal solar cells with oxide charge-transport layers.

    Science.gov (United States)

    Hyun, Byung-Ryool; Choi, Joshua J; Seyler, Kyle L; Hanrath, Tobias; Wise, Frank W

    2013-12-23

    Oxides are commonly employed as electron-transport layers in optoelectronic devices based on semiconductor nanocrystals, but are relatively rare as hole-transport layers. We report studies of NiO hole-transport layers in PbS nanocrystal photovoltaic structures. Transient fluorescence experiments are used to verify the relevant energy levels for hole transfer. On the basis of these results, planar heterojunction devices with ZnO as the photoanode and NiO as the photocathode were fabricated and characterized. Solution-processed devices were used to systematically study the dependence on nanocrystal size and achieve conversion efficiency as high as 2.5%. Optical modeling indicates that optimum performance should be obtained with thinner oxide layers than can be produced reliably by solution casting. Room-temperature sputtering allows deposition of oxide layers as thin as 10 nm, which enables optimization of device performance with respect to the thickness of the charge-transport layers. The best devices achieve an open-circuit voltage of 0.72 V and efficiency of 5.3% while eliminating most organic material from the structure and being compatible with tandem structures.

  9. A novel polarization demodulation method using polarization beam splitter (PBS) for dynamic pressure sensor

    Science.gov (United States)

    Su, Yang; Zhou, Hua; Wang, Yiming; Shen, Huiping

    2018-03-01

    In this paper we propose a new design to demodulate polarization properties induced by pressure using a PBS (polarization beam splitter), which is different with traditional polarimeter based on the 4-detector polarization measurement approach. The theoretical model is established by Muller matrix method. Experimental results confirm the validity of our analysis. Proportional relationships and linear fit are found between output signal and applied pressure. A maximum sensitivity of 0.092182 mv/mv is experimentally achieved and the frequency response exhibits a <0.14 dB variation across the measurement bandwidth. The sensitivity dependence on incident SOP (state of polarization) is investigated. The simple and all-fiber configuration, low-cost and high speed potential make it promising for fiber-based dynamic pressure sensing.

  10. Policy-making under uncertainty: commentary upon the European Union Emissions Trading Scheme

    International Nuclear Information System (INIS)

    Haar, L.N.

    2006-01-01

    The authors undertake a critical assessment of the intellectual foundations supporting the new European Union (EU) Emissions Trading Scheme (ETS, or the Scheme), the cornerstone of polices designed to achieve the targets of the Kyoto Agreement of reducing emissions of greenhouse gases (GHG). Despite its considerable scope, the authors found that officially sponsored research and academic efforts in support of ETS were surprisingly limited. Importantly, in advance of implementation, a definitive consensus on both the potential economic impact and the usefulness of the Scheme in reducing the GHG emissions had not been reached. Reviewing the literature, the authors encountered varying and, at times, conflicting viewpoints, officially and in academic research, on the potential economic impact of the Scheme. These included attempts to quantify its benefits and costs, raising concern that this huge and encompassing multi-national policy initiative may have been launched with inadequate intellectual ground-work. According to the authors consistency between the ETS and other EU policies, such as those relating to energy, should have been a key concern, but such aspects have received only minimal attention in both official and academic research. The European Commission has promoted open and competitive markets for gas and power across member states, but the record in achieving such conditions is relatively poor and the authors argue that, as a result, the environmental objectives of the EU Scheme may not be thwarted. In addition, continuing disagreement over the Kyoto Agreement itself-especially with regard to its potential costs and benefits-further frustrates efforts to rigorously justify a policy in support of reducing GHG emissions. The authors argue that, given the scope of the EU Scheme, the paucity of research evidencing that it is likely to succeed in reducing GHG emissions in the form of CO 2 is surprising and should be of concern to those affected by it along with

  11. Policy-making under uncertainty: Commentary upon the European Union Emissions Trading Scheme

    International Nuclear Information System (INIS)

    Haar, Laura N.; Haar, Lawrence

    2006-01-01

    The authors undertake a critical assessment of the intellectual foundations supporting the new European Union (EU) Emissions Trading Scheme (ETS, or the Scheme), the cornerstone of polices designed to achieve the targets of the Kyoto Agreement of reducing emissions of greenhouse gases (GHG). Despite its considerable scope, the authors found that officially sponsored research and academic efforts in support of ETS were surprisingly limited. Importantly, in advance of implementation, a definitive consensus on both the potential economic impact and the usefulness of the Scheme in reducing the GHG emissions had not been reached. Reviewing the literature, the authors encountered varying and, at times, conflicting viewpoints, officially and in academic research, on the potential economic impact of the Scheme. These included attempts to quantify its benefits and costs, raising concern that this huge and encompassing multi-national policy initiative may have been launched with inadequate intellectual ground-work. According to the authors consistency between the ETS and other EU policies, such as those relating to energy, should have been a key concern, but such aspects have received only minimal attention in both official and academic research. The European Commission has promoted open and competitive markets for gas and power across member states, but the record in achieving such conditions is relatively poor and the authors argue that, as a result, the environmental objectives of the EU Scheme may not be thwarted. In addition, continuing disagreement over the Kyoto Agreement itself-especially with regard to its potential costs and benefits-further frustrates efforts to rigorously justify a policy in support of reducing GHG emissions. The authors argue that, given the scope of the EU Scheme, the paucity of research evidencing that it is likely to succeed in reducing GHG emissions in the form of CO 2 is surprising and should be of concern to those affected by it along with

  12. Pricing schemes for new drugs: a welfare analysis.

    Science.gov (United States)

    Levaggi, Rosella

    2014-02-01

    Drug price regulation is acquiring increasing significance in the investment choices of the pharmaceutical sector. The overall objective is to determine an optimal trade-off between the incentives for innovation, consumer protection, and value for money. However, price regulation is itself a source of distortion. In this study, we examine the welfare properties of listing through a bargaining process and value-based pricing schemes. The latter are superior instruments to uncertain listing processes for maximising total welfare, but the distribution of the benefits between consumers and the industry depends on rate of rebate chosen by the regulator. However, through an appropriate choice, it is always possible to define a value-based pricing scheme with risk sharing, which both consumers and the industry prefer to an uncertain bargaining process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. How are pharmaceutical patent term extensions justified? Australia's evolving scheme.

    Science.gov (United States)

    Lawson, Charles

    2013-12-01

    This article examines the evolving patent term extension schemes under the Patents Act 1903 (Cth), the Patents Act 1952 (Cth) and the Patents Act 1990 (Cth). The analysis traces the change from "inadequate remuneration" to a scheme directed specifically at certain pharmaceuticals. An examination of the policy justification shows there are legitimate questions about the desirability of any extension. The article concludes that key information provisions in the Patents Act 1990 (Cth) that might assist a better policy analysis are presently not working and that any justification needs evidence demonstrating that the benefits of patent term extensions to the community as a whole outweigh the costs and that the objectives of extensions can only be achieved by restricting competition.

  14. Solid municipal waste processing plants: Cost benefit analysis

    International Nuclear Information System (INIS)

    Gerardi, V.

    1992-01-01

    This paper performs cost benefit analyses on three solid municipal waste processing alternatives with plants of diverse daily outputs. The different processing schemes include: selected wastes incineration with the production of refuse derived fuels; selected wastes incineration with the production of refuse derived fuels and compost; pyrolysis with energy recovery in the form of electric power. The plant daily outputs range from 100 to 300 tonnes for the refuse derived fuel alternatives, and from 200 to 800 tonnes for the pyrolysis/power generation scheme. The cost analyses consider investment periods of fifteen years in duration and interest rates of 5%

  15. The CdS/CdSe/ZnS Photoanode Cosensitized Solar Cells Basedon Pt, CuS, Cu2S, and PbS Counter Electrodes

    Directory of Open Access Journals (Sweden)

    Tung Ha Thanh

    2014-01-01

    Full Text Available Highly ordered mesoporous TiO2 modified by CdS, CdSe, and ZnS quantum dots (QDs was fabricated by successive ionic layer adsorption and reaction (SILAR method. The quantity of material deposition seems to be affected not only by the employed deposition method but also and mainly by the nature of the underlying layer. The CdS, CdSe, and ZnS QDs modification expands the photoresponse range of mesoporous TiO2 from ultraviolet region to visible range, as confirmed by UV-Vis spectrum. Optimized anode electrodes led to solar cells producing high current densities. Pt, CuS, PbS, and Cu2S have been used as electrocatalysts on counter electrodes. The maximum solar conversion efficiency reached in this work was 1.52% and was obtained by using Pt electrocatalyst. CuS, PbS, and Cu2S gave high currents and this was in line with the low charge transfer resistances recorded in their case.

  16. Optimization bitumen-based upgrading and refining schemes

    Energy Technology Data Exchange (ETDEWEB)

    Munteanu, M.; Chen, J. [National Centre for Upgrading Technology, Devon, AB (Canada); Natural Resources Canada, Devon, AB (Canada). CanmetENERGY

    2009-07-01

    This poster highlighted the results of a study in which the entire refining scheme for Canadian bitumen as feedstocks was modelled and simulated under different process configurations, operating conditions and product structures. The aim of the study was to optimize the economic benefits, product quality and energy use under a range of operational scenarios. Optimal refining schemes were proposed along with process conditions for existing refinery configurations and objectives. The goal was to provide guidelines and information for upgrading and refining process design and retrofitting. Critical steps were identified with regards to the upgrading process. It was concluded that the information obtained from this study would lead to significant improvement in process performance and operations, and in reducing the capital cost for building new upgraders and refineries. The simulation results provided valuable information for increasing the marketability of bitumen, reducing greenhouse gas emissions and other environmental impacts associated with bitumen upgrading and refining. tabs., figs.

  17. Molecular Dynamics Study of Self-Assembly of Aqueous Solutions of Poly[9,9-bis(4-Sulfonylbutoxyphenylphenyl Fluorene-2,7-diyl-2,2’-Bithiophene] (PBS-PF2T in the Presence of Pentaethylene Glycol Monododecyl Ether (C12E5

    Directory of Open Access Journals (Sweden)

    Beverly Stewart

    2016-05-01

    Full Text Available Results are presented using molecular dynamics (MD of the self-assembly of the conjugated polyelectrolyte poly[9,9-bis(4-sulfonylbutoxyphenylphenyl fluorene-2,7-diyl-2,2’-bithiophene] (PBS-PF2T with 680 mM pentaethylene glycol monododecyl ether (C12E5 in water. Simulations are used to examine the interaction between PBS-PF2T and C12E5 and suggest a break-up of PBS-PF2T aggregates in solution. These systems are dominated by the formation of cylindrical phases at temperatures between 0 °C and 20 °C and also between 45 °C and 90 °C. More diffuse phases are seen to occur between 20 °C and 45 °C and also above 90 °C. Simulations are related to previous computational and experimental studies on PBS-PF2T aggregation in the presence of tetraethylene glycol monododecyl ether (C12E4 in bulk and thin films.

  18. Dual discounting in cost-benefit analysis for environmental impacts

    International Nuclear Information System (INIS)

    Kula, Erhun; Evans, David

    2011-01-01

    Discounting has been a long-established intertemporal efficiency tool in cost-benefit analysis which focuses on project selection at communal level with a view to maximising the social welfare. However, with the relentless growth in environmental stress that, in good parts, stems from investment projects the established criterion in discounting appears to be inadequate especially when environmental issues are taken into consideration. This paper looks at how dual focus on efficiency and sustainability can be achieved by using dual discounting, i.e. discounting environmental benefits separately and differently from other costs and benefits and applies this alternative criterion to an afforestation scheme in the United Kingdom which contains carbon sequestration in addition to timber benefits.

  19. An Improvement to a Multi-Client Searchable Encryption Scheme for Boolean Queries.

    Science.gov (United States)

    Jiang, Han; Li, Xue; Xu, Qiuliang

    2016-12-01

    The migration of e-health systems to the cloud computing brings huge benefits, as same as some security risks. Searchable Encryption(SE) is a cryptography encryption scheme that can protect the confidentiality of data and utilize the encrypted data at the same time. The SE scheme proposed by Cash et al. in Crypto2013 and its follow-up work in CCS2013 are most practical SE Scheme that support Boolean queries at present. In their scheme, the data user has to generate the search tokens by the counter number one by one and interact with server repeatedly, until he meets the correct one, or goes through plenty of tokens to illustrate that there is no search result. In this paper, we make an improvement to their scheme. We allow server to send back some information and help the user to generate exact search token in the search phase. In our scheme, there are only two round interaction between server and user, and the search token has [Formula: see text] elements, where n is the keywords number in query expression, and [Formula: see text] is the minimum documents number that contains one of keyword in query expression, and the computation cost of server is [Formula: see text] modular exponentiation operation.

  20. On the feedback error compensation for adaptive modulation and coding scheme

    KAUST Repository

    Choi, Seyeong

    2011-11-25

    In this paper, we consider the effect of feedback error on the performance of the joint adaptive modulation and diversity combining (AMDC) scheme which was previously studied with an assumption of perfect feedback channels. We quantify the performance of two joint AMDC schemes in the presence of feedback error, in terms of the average spectral efficiency, the average number of combined paths, and the average bit error rate. The benefit of feedback error compensation with adaptive combining is also quantified. Selected numerical examples are presented and discussed to illustrate the effectiveness of the proposed feedback error compensation strategy with adaptive combining. Copyright (c) 2011 John Wiley & Sons, Ltd.

  1. Enhanced photoelectrochemical performance of PbS sensitized Sb–SnO{sub 2}/TiO{sub 2} nanotube arrays electrode under visible light illumination

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jia; Tang, Chengli [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Hao, E-mail: xuhao@mail.xjtu.edu.cn [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Yan, Wei, E-mail: yanwei@mail.xjtu.edu.cn [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049 (China)

    2015-06-05

    Highlights: • Sb–SnO{sub 2} is used to modify TiO{sub 2} NTAs by microwave method. • PbS is employed to sensitive Sb–SnO{sub 2}/TiO{sub 2} NTAs by S-SILAR method. • Sb–SnO{sub 2} improves electrons transfer and PbS enhances visible light absorption. • The composite electrode shows enhanced photoelectrochemical properties. • The composite electrode exhibits high hydrogen evolution and high QE. - Abstract: The novel PbS sensitized Sb–SnO{sub 2}/TiO{sub 2} nanotube arrays (NTAs) composite electrode (PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs) was fabricated by microwave combined with sonication-assisted successive ionic layer adsorption and reaction technique (S-SILAR). The obtained electrodes were characterized by field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance absorption spectra techniques. Enhanced photocurrent (15.52 mA/cm{sup 2}) of the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode was observed and can be attributed to the facile photo-generated electrons transfer and enhanced charge separation efficiency. Furthermore, the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs composite electrode shows a higher H{sub 2} production rate than the Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode and PbS/TiO{sub 2} NTAs electrode. The results indicate that the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode is a promising photoanode in visible photocatalytic water splitting.

  2. Twenty-year trends in benzodiazepine dispensing in the Australian population.

    Science.gov (United States)

    Islam, M M; Conigrave, K M; Day, C A; Nguyen, Y; Haber, P S

    2014-01-01

    Considerable concern has been expressed about overprescribing of benzodiazepines and related harms. Past analyses have relied on World Health Organization-defined daily doses (DDD) which are sometimes out of keeping with clinical usage. This study examines 20-year (1992-2011) trends of benzodiazepine dispensing in Australia using both DDD and Ashton equivalent dose. Data from the Drug Utilisation Sub-Committee and the Pharmaceutical Benefits Scheme (PBS) website were analysed. Trends in number of prescriptions, DDD/1000 people/day and DDD/prescription were examined over time, and between states/territories. In the 20-year period, 174 080 904 scripts were recorded, with temazepam the most dispensed benzodiazepine (35% of scripts), followed by diazepam (23%). Overall recorded utilisation fell from 27.7 DDD/1000 people/day in 1992 to 20.8 in 2011 (24.9% decrease). There were striking changes in use of individual benzodiazepines over time, with reductions in oxazepam and flunitrazepam and dramatic increases in alprazolam. Since 1998, there has been a steady increase, albeit modest, in per script DDD. The DDD/1000 people/day for items dispensed through PBS/Repatriaton-PBS was highest in Tasmania and lowest in Northern Territory. Despite a modest overall decline in the amount of benzodiazepine dispensed, the level of use is still likely to reflect relative over-prescribing given the paucity of accepted indications for long-term use. Since 1998, there was a polynomial increase in quantity dispensed per script. The WHO-defined DDD for clonazepam seems inappropriate and could impede monitoring of its abuse. Other problems include lack of national data for medications not subsidised on PBS/Repatriation PBS. A broad policy approach is required, not one which targets only one particular benzodiazepine. © 2013 The Authors; Internal Medicine Journal © 2013 Royal Australasian College of Physicians.

  3. Impact of renewables on electricity markets – Do support schemes matter?

    International Nuclear Information System (INIS)

    Winkler, Jenny; Gaio, Alberto; Pfluger, Benjamin; Ragwitz, Mario

    2016-01-01

    Rising renewable shares influence electricity markets in several ways: among others, average market prices are reduced and price volatility increases. Therefore, the “missing money problem” in energy-only electricity markets is more likely to occur in systems with high renewable shares. Nevertheless, renewables are supported in many countries due to their expected benefits. The kind of support instrument can however influence the degree to which renewables influence the market. While fixed feed-in tariffs lead to higher market impacts, more market-oriented support schemes such as market premiums, quota systems and capacity-based payments decrease the extent to which markets are affected. This paper analyzes the market impacts of different support schemes. For this purpose, a new module is added to an existing bottom-up simulation model of the electricity market. In addition, different degrees of flexibility in the electricity system are considered. A case study for Germany is used to derive policy recommendations regarding the choice of support scheme. - Highlights: •Renewable support schemes matter regarding the impact on electricity markets. •Market-oriented support schemes reduce the impact on electricity markets. •More flexible electricity systems reduce the need for market participation. •Sliding premiums combine market integration with a productive risk allocation.

  4. Studying and comparing spectrum efficiency and error probability in GMSK and DBPSK modulation schemes

    Directory of Open Access Journals (Sweden)

    Juan Mario Torres Nova

    2008-09-01

    Full Text Available Gaussian minimum shift keying (GMSK and differential binary phase shift keying (DBPSK are two digital modulation schemes which are -frequently used in radio communication systems; however, there is interdependence in the use of its benefits (spectral efficiency, low bit error rate, low inter symbol interference, etc. Optimising one parameter creates problems for another; for example, the GMSK scheme succeeds in reducing bandwidth when introducing a Gaussian filter into an MSK (minimum shift ke-ying modulator in exchange for increasing inter-symbol interference in the system. The DBPSK scheme leads to lower error pro-bability, occupying more bandwidth; it likewise facilitates synchronous data transmission due to the receiver’s bit delay when re-covering a signal.

  5. SU-E-T-188: Commission of World 1st Commercial Compact PBS Proton System

    Energy Technology Data Exchange (ETDEWEB)

    Ding, X; Patel, B; Song, X; Syh, J; Syh, J; Zhang, J; Freund, D; Rosen, L; Wu, H [Willis-Knighton Medical Center, Shreveport, LA (United States)

    2015-06-15

    Purpose: ProteusONE is the 1st commercial compact PBS proton system with an upstream scanning gantry and C230 cyclotron. We commissioned XiO and Raystation TPS simultaneously. This is a summary of beam data collection, modeling, and verification and comparison without range shiter for this unique system with both TPS. Methods: Both Raystation and XiO requires the same measurements data: (i) integral depth dose(IDDs) of single central spot measured in water tank; (ii) absolute dose calibration measured at 2cm depth of water with mono-energetic 10×10 cm2 field with spot spacing 4mm, 1MU per spot; and (iii) beam spot characteristics in air at 0cm and ± 20cm away from ISO. To verify the beam model for both TPS, same 15 cube plans were created to simulate different treatment sites, target volumes and positions. PDDs of each plan were measured using a Multi-layer Ionization Chamber(MLIC), absolute point dose verification were measured using PPC05 in water tank and patient-specific QA were measured using MatriXX PT, a 2D ion chamber array. Results: All the point dose measurements at midSOBP were within 2% for both XiO and Raystation. However, up to 5% deviations were observed in XiO’s plans at shallow depth while within 2% in Raystation plans. 100% of the ranges measured were within 1 mm with maximum deviation of 0.5 mm. 20 patient specific plan were generated and measured in 3 planes (distal, proximal and midSOBP) in Raystation. The average of gamma index is 98.7%±3% with minimum 94% Conclusions: Both TPS were successfully commissioned and can be safely deployed for clinical use for ProteusONE. Based on our clinical experience in PBS planning, user interface, function and workflow, we preferably use Raystation as our main clinical TPS. Gamma Index >95% at 3%/3 mm criteria is our institution action level for patient specific plan QAs.

  6. Unwanted pregnancy: The outer boundary of "treatment injury" in the New Zealand accident compensation scheme.

    Science.gov (United States)

    Tobin, Rosemary

    2015-09-01

    The New Zealand accident compensation scheme has undergone many changes over the years and these changes are reflected in the way unwanted pregnancy claims have been dealt with under the regime. The New Zealand Supreme Court has now confirmed that pregnancy as a result of medical misadventure can be classified as a personal injury under the scheme with the result that the woman patient is entitled to the benefits of the scheme and may not pursue a common law claim against the medical practitioner. This article analyses two recent decisions in the context of consideration of the changing fortunes of the unwanted pregnancy claims.

  7. Efficiency enhancement of solid-state PbS quantum dot-sensitized solar cells with Al2O3 barrier layer

    KAUST Repository

    Brennan, Thomas P.; Trejo, Orlando; Roelofs, Katherine E.; Xu, John; Prinz, Fritz B.; Bent, Stacey F.

    2013-01-01

    Atomic layer deposition (ALD) was used to grow both PbS quantum dots and Al2O3 barrier layers in a solid-state quantum dot-sensitized solar cell (QDSSC). Barrier layers grown prior to quantum dots resulted in a near-doubling of device efficiency (0.30% to 0.57%) whereas barrier layers grown after quantum dots did not improve efficiency, indicating the importance of quantum dots in recombination processes. © 2013 The Royal Society of Chemistry.

  8. Seasonal temperature is associated with Parkinson's disease prescriptions: an ecological study

    Science.gov (United States)

    Rowell, David; Nghiem, Son; Ramagopalan, Sreeram; Meier, Ute-Christiane

    2017-12-01

    The aim of this study is to test what effect the weather may have on medications prescribed to treat Parkinson's disease. Twenty-three years of monthly time, series data was sourced from the Pharmaceutical Benefits Scheme (PBS) and the Bureau of Meteorology (BOM). Data were available for eight states and territories and their corresponding capital cities. The dependent variable was the aggregate levodopa equivalent dose (LED) for 51 Parkinson's medications identified on the PBS. Two explanatory variables of interest, temperature and solar exposure, were identified in the BOM data set. Linear and cosinor models were estimated with fixed and random effects, respectively. The prescribed LED was 4.2% greater in January and 4.5% lower in July. Statistical analysis showed that temperature was associated with the prescription of Parkinson medications. Our results suggest seasonality exists in Parkinson's disease symptoms and this may be related to temperature. Further work is needed to confirm these findings and understand the underlying mechanisms as a better understanding of the causes of any seasonal variation in Parkinson's disease may help clinicians and patients manage the disease more effectively.

  9. Noncovalent Attachment of PbS Quantum Dots to Single- and Multiwalled Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Anirban Das

    2014-01-01

    Full Text Available Attachment of PbS quantum dots (QD to single-walled carbon nanotubes (SWNT and multiwalled carbon nanotubes (MWCNT is described; wherein commercially obtained PbS-QD of size 2.7 nm, stabilized by oleic acid, are added to a suspension of single- or multiwalled carbon nanotubes (CNT prefunctionalized noncovalently with 1,2-benzenedimethanethiol (1,2-BDMT in ethanol. The aromatic part of 1,2-BDMT attaches to the CNT by π-π stacking interactions, noncovalently functionalizing the CNT. The thiol part of the 1,2-BDMT on the functionalized CNT replaces oleic acid on the surface of the QD facilitating the noncovalent attachment of the QD to the CNT. The composites were characterized by TEM and FTIR spectroscopy. Quenching of NIR fluorescence of the PbS-QD on attachment to the carbon nanotubes (CNT was observed, indicating FRET from the QD to the CNT.

  10. Exact analysis of Packet Reversed Packet Combining Scheme and Modified Packet Combining Scheme; and a combined scheme

    International Nuclear Information System (INIS)

    Bhunia, C.T.

    2007-07-01

    Packet combining scheme is a well defined simple error correction scheme for the detection and correction of errors at the receiver. Although it permits a higher throughput when compared to other basic ARQ protocols, packet combining (PC) scheme fails to correct errors when errors occur in the same bit locations of copies. In a previous work, a scheme known as Packet Reversed Packet Combining (PRPC) Scheme that will correct errors which occur at the same bit location of erroneous copies, was studied however PRPC does not handle a situation where a packet has more than 1 error bit. The Modified Packet Combining (MPC) Scheme that can correct double or higher bit errors was studied elsewhere. Both PRPC and MPC schemes are believed to offer higher throughput in previous studies, however neither adequate investigation nor exact analysis was done to substantiate this claim of higher throughput. In this work, an exact analysis of both PRPC and MPC is carried out and the results reported. A combined protocol (PRPC and MPC) is proposed and the analysis shows that it is capable of offering even higher throughput and better error correction capability at high bit error rate (BER) and larger packet size. (author)

  11. Lightweight Data Aggregation Scheme against Internal Attackers in Smart Grid Using Elliptic Curve Cryptography

    Directory of Open Access Journals (Sweden)

    Debiao He

    2017-01-01

    Full Text Available Recent advances of Internet and microelectronics technologies have led to the concept of smart grid which has been a widespread concern for industry, governments, and academia. The openness of communications in the smart grid environment makes the system vulnerable to different types of attacks. The implementation of secure communication and the protection of consumers’ privacy have become challenging issues. The data aggregation scheme is an important technique for preserving consumers’ privacy because it can stop the leakage of a specific consumer’s data. To satisfy the security requirements of practical applications, a lot of data aggregation schemes were presented over the last several years. However, most of them suffer from security weaknesses or have poor performances. To reduce computation cost and achieve better security, we construct a lightweight data aggregation scheme against internal attackers in the smart grid environment using Elliptic Curve Cryptography (ECC. Security analysis of our proposed approach shows that it is provably secure and can provide confidentiality, authentication, and integrity. Performance analysis of the proposed scheme demonstrates that both computation and communication costs of the proposed scheme are much lower than the three previous schemes. As a result of these aforementioned benefits, the proposed lightweight data aggregation scheme is more practical for deployment in the smart grid environment.

  12. Heterojunction PbS Nanocrystal Solar Cells with Oxide Charge-Transport Layers

    KAUST Repository

    Hyun, Byung-Ryool

    2013-12-23

    Oxides are commonly employed as electron-transport layers in optoelectronic devices based on semiconductor nanocrystals, but are relatively rare as hole-transport layers. We report studies of NiO hole-transport layers in PbS nanocrystal photovoltaic structures. Transient fluorescence experiments are used to verify the relevant energy levels for hole transfer. On the basis of these results, planar heterojunction devices with ZnO as the photoanode and NiO as the photocathode were fabricated and characterized. Solution-processed devices were used to systematically study the dependence on nanocrystal size and achieve conversion efficiency as high as 2.5%. Optical modeling indicates that optimum performance should be obtained with thinner oxide layers than can be produced reliably by solution casting. Roomerature sputtering allows deposition of oxide layers as thin as 10 nm, which enables optimization of device performance with respect to the thickness of the charge-transport layers. The best devices achieve an open-circuit voltage of 0.72 V and efficiency of 5.3% while eliminating most organic material from the structure and being compatible with tandem structures. © 2013 American Chemical Society.

  13. Utilization of health-care schemes: A ground reality of Indian scenario

    Directory of Open Access Journals (Sweden)

    Aditi Sharma

    2018-01-01

    Full Text Available Health-care system in a society must be built around the term of equity so that each individual should have equal opportunities for maintaining good health, but human societies are characterized by unevenness at every aspect, and it has even not spared the health-care system. Despite great improvements in the oral health status of population across the world, health problems continue to be a major public health concern. India's health system faces the ongoing challenge of responding to the needs of the most disadvantaged groups of the society. Thus, to reduce inequalities in health and ensuring equity in oral health care, India as one of the developing countries in the world have taken steps at center as well as state level to bridge the gap between poor and rich in terms of health care. These schemes are built to touch the lives of the remotest people in the country. The government is boosting its strategies and augmenting its reach mechanisms to ensure that not a soul is dispossessed of any benefits, which arise from the virtue of this scheme. The present review concludes that though these schemes appear to be pro-poor and are inclusive of disadvantaged minorities, the scheme suffers from adverse selection. These schemes have the potential to play an important role in India's move toward universal health coverage.

  14. Social health insurance contributes to universal coverage in South Africa, but generates inequities: survey among members of a government employee insurance scheme.

    Science.gov (United States)

    Goudge, Jane; Alaba, Olufunke A; Govender, Veloshnee; Harris, Bronwyn; Nxumalo, Nonhlanhla; Chersich, Matthew F

    2018-01-04

    Many low- and middle-income countries are reforming their health financing mechanisms as part of broader strategies to achieve universal health coverage (UHC). Voluntary social health insurance, despite evidence of resulting inequities, is attractive to policy makers as it generates additional funds for health, and provides access to a greater range of benefits for the formally employed. The South African government introduced a voluntary health insurance scheme (GEMS) for government employees in 2005 with the aim of improving access to care and extending health coverage. In this paper we ask whether the new scheme has assisted in efforts to move towards UHC. Using a cross-sectional survey across four of South Africa's nine provinces, we interviewed 1329 government employees, from the education and health sectors. Data were collected on socio-demographics, insurance coverage, health status and utilisation of health care. Multivariate logistic regression was used to determine if service utilisation was associated with insurance status. A quarter of respondents remained uninsured, even higher among 20-29 year olds (46%) and lower-skilled employees (58%). In multivariate analysis, the odds of an outpatient visit and hospital admission for the uninsured was 0.3 fold that of the insured. Cross-subsidisation within the scheme has provided lower-paid civil servants with improved access to outpatient care at private facilities and chronic medication, where their outpatient (0.54 visits/month) and inpatient utilisation (10.1%/year) approximates that of the overall population (29.4/month and 12.2% respectively). The scheme, however, generated inequities in utilisation among its members due to its differential benefit packages, with, for example, those with the most benefits having 1.0 outpatient visits/month compared to 0.6/month with lowest benefits. By introducing the scheme, the government chose to prioritise access to private sector care for government employees, over

  15. Finite Boltzmann schemes

    NARCIS (Netherlands)

    Sman, van der R.G.M.

    2006-01-01

    In the special case of relaxation parameter = 1 lattice Boltzmann schemes for (convection) diffusion and fluid flow are equivalent to finite difference/volume (FD) schemes, and are thus coined finite Boltzmann (FB) schemes. We show that the equivalence is inherent to the homology of the

  16. Dissociation of water and Acetic acid on PbS from first principles

    Science.gov (United States)

    Satta, Alessandra; Ruggerone, Paolo; de Giudici, Giovanni

    2008-03-01

    The adsorption of complex molecules at mineral surfaces are crucial ingredients for understanding the mechanisms that rule the interaction between minerals and the biosphere and for predicting both the stability and the reactivity of minerals. The present work focuses mainly on the early stages of different adsorption reactions occurring at both the cleavage surface and a high-index vicinal surface of galena (PbS). We have studied the dissociation mechanism of water and acetic acid on the galena surfaces by means of ab initio calculations within the framework of the density functional theory in the generalized gradient approximation and of pseudopotential approach. The calculated adsorption energies of the molecules indicate the stepped surface as the most reactive, as expected. The free energy surface during the reaction process has been explored via metadynamics[1]. The optimized configurations of both reactants and products obtained, were then used to accurately calculate the dissociation energy via the Nudge Elastic Band method[2]. [1] A. Laio and M. Parrinello, PNAS 99, 12562 (2002). [2] G. Mills and H. Jonsson, Phys. Rev. Lett. 72, 1124 (1994).

  17. 1.01-Pb/s (12 SDM/222 WDM/456 Gb/s) Crosstalk-managed Transmission with 91.4-b/s/Hz Aggregate Spectral Efficiency

    DEFF Research Database (Denmark)

    Takara, H.; Sano, A.; Kobayashi, T.

    2012-01-01

    We demonstrate 1.01-Pb/s transmission over 52 km with the highest aggregate spectral efficiency of 91.4 b/s/Hz by using low-crosstalk one-ring-structured 12-core fiber. Our multi-core fiber and compact fan-in/fan-out devices are designed to support high-order modulation formats up to 32-QAM in SD...

  18. Household perceptions and their implications for enrollment in the National Health Insurance Scheme in Ghana.

    NARCIS (Netherlands)

    Jehu-Appiah, C.; Aryeetey, G.C.; Agyepong, I.; Spaan, E.J.; Baltussen, R.M.

    2012-01-01

    OBJECTIVE: This paper identifies, ranks and compares perceptions of insured and uninsured households in Ghana on health care providers (quality of care, service delivery adequacy, staff attitudes), health insurance schemes (price, benefits and convenience) and community attributes (health 'beliefs

  19. Global mechanisms for sustaining and enhancing PES schemes

    International Nuclear Information System (INIS)

    Farley, Josh; Moulaert, Azur; Lee, Dan; Krause, Abby; Aquino, Andre; Daniels, Amy

    2010-01-01

    An international payment for ecosystem service (IPES) schemes may be one of the only mechanisms available to stimulate the provision of vital non-marketed ecosystem services at the global level, as those nations that benefit from global ecosystem services (GES) cannot readily force other sovereign nations to provide them. Currently, international trade offers trillions of dollars in incentives for countries to convert natural capital into marketable goods and services, and few payments to entice countries to conserve natural capital in order to sustain critical non-marketed ecosystem services. We examine the biophysical characteristics of climate change and biodiversity to understand the obstacles to developing effective IPES schemes. We find that none of the existing schemes for providing GES are adequate, given the scale of the problem. A cap and auction scheme for CO 2 emissions among wealthy nations could fund IPES and simultaneously deter carbon emissions. To disburse funds, we should adapt Brazil's ICMS ecologico, and apportion available funds to targeted countries in proportion to how well they meet specific criteria designed to measure the provision of GES. Individual countries can then develop their own policies for increasing provision of these services, ensured of compensation if they do so. Indirect IPES should include funding for freely available technologies that protect or provide GES, such as the low carbon energy alternatives that will be essential for curbing climate change. Markets rely on the price mechanism to generate profits, which rations technology to those who can afford it, reducing adoption rates, innovation and total value. (author)

  20. Joint support schemes for renewable generation and barriers for implementation

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik; Hansen, Lise-Lotte Pade; Schröder, Sascha Thorsten

    2012-01-01

    expansion with lower prices that will affect existing conventional producers. Supporting that development will be opposed by producers whereas consumers will support such a strategy. However, the investment will be influenced by decisions of producers and the option of securing connection to other markets...... the 2020 RES targets. The countries might also find themselves competing for investment in a market with limited capital available. In both cases, the cost-efficiency of the renewable support policies will be reduced from a coordinated solution. We suggest possible policy solutions for joint support......EU has opened for using joint support schemes as support for promoting renewable energy to meet the 2020 targets. Countries are supporting renewable investment by many different types of support schemes and with different levels of support. The potential coordination benefits with more efficient...

  1. Preferences for benefit packages for community-based health insurance: an exploratory study in Nigeria

    Directory of Open Access Journals (Sweden)

    Nnenna Tasie

    2010-06-01

    Full Text Available Abstract Background It is important that community-based health insurance (CBHI schemes are designed in such a way as to ensure the relevance of the benefit packages to potential clients. Hence, this paper provides an understanding of the preferred benefit packages by different economic status groups as well as urban and rural dwellers for CBHI in Southeast Nigeria. Methods The study took place in rural, urban and semi-urban communities of south-east Nigeria. A questionnaire was used to collect information from 3070 randomly picked household heads. Focus group discussions were used to collect qualitative data. Data was examined for links between preferences for benefit packages with SES and geographic residence of the respondents. Results Respondents in the rural areas and in the lower SES preferred a comprehensive benefit package which includes all inpatient, outpatient and emergencies services, while those in urban areas as well as those in the higher SES group showed a preference for benefit packages which will cover only basic disease control interventions. Conclusion Equity concerns in preferences for services to be offered by the CBHI scheme should be addressed for CBHI to succeed in different contexts.

  2. Preferences for benefit packages for community-based health insurance: an exploratory study in Nigeria.

    Science.gov (United States)

    Onwujekwe, Obinna; Onoka, Chima; Uguru, Nkoli; Nnenna, Tasie; Uzochukwu, Benjamin; Eze, Soludo; Kirigia, Joses; Petu, Amos

    2010-06-12

    It is important that community-based health insurance (CBHI) schemes are designed in such a way as to ensure the relevance of the benefit packages to potential clients. Hence, this paper provides an understanding of the preferred benefit packages by different economic status groups as well as urban and rural dwellers for CBHI in Southeast Nigeria. The study took place in rural, urban and semi-urban communities of south-east Nigeria. A questionnaire was used to collect information from 3070 randomly picked household heads. Focus group discussions were used to collect qualitative data. Data was examined for links between preferences for benefit packages with SES and geographic residence of the respondents. Respondents in the rural areas and in the lower SES preferred a comprehensive benefit package which includes all inpatient, outpatient and emergencies services, while those in urban areas as well as those in the higher SES group showed a preference for benefit packages which will cover only basic disease control interventions. Equity concerns in preferences for services to be offered by the CBHI scheme should be addressed for CBHI to succeed in different contexts.

  3. Theoretical Benefits of Dynamic Collimation in Pencil Beam Scanning Proton Therapy for Brain Tumors: Dosimetric and Radiobiological Metrics

    Energy Technology Data Exchange (ETDEWEB)

    Moignier, Alexandra, E-mail: alexandra-moignier@uiowa.edu [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa (United States); Gelover, Edgar; Wang, Dongxu; Smith, Blake; Flynn, Ryan [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa (United States); Kirk, Maura; Lin, Liyong; Solberg, Timothy; Lin, Alexander [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Hyer, Daniel [Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa (United States)

    2016-05-01

    Purpose: To quantify the dosimetric benefit of using a dynamic collimation system (DCS) for penumbra reduction during the treatment of brain tumors by pencil beam scanning proton therapy (PBS PT). Methods and Materials: Collimated and uncollimated brain treatment plans were created for 5 patients previously treated with PBS PT and retrospectively enrolled in an institutional review board–approved study. The in-house treatment planning system, RDX, was used to generate the plans because it is capable of modeling both collimated and uncollimated beamlets. The clinically delivered plans were reproduced with uncollimated plans in terms of target coverage and organ at risk (OAR) sparing to ensure a clinically relevant starting point, and collimated plans were generated to improve the OAR sparing while maintaining target coverage. Physical and biological comparison metrics, such as dose distribution conformity, mean and maximum doses, normal tissue complication probability, and risk of secondary brain cancer, were used to evaluate the plans. Results: The DCS systematically improved the dose distribution conformity while preserving the target coverage. The average reduction of the mean dose to the 10-mm ring surrounding the target and the healthy brain were 13.7% (95% confidence interval [CI] 11.6%-15.7%; P<.0001) and 25.1% (95% CI 16.8%-33.4%; P<.001), respectively. This yielded an average reduction of 24.8% (95% CI 0.8%-48.8%; P<.05) for the brain necrosis normal tissue complication probability using the Flickinger model, and 25.1% (95% CI 16.8%-33.4%; P<.001) for the risk of secondary brain cancer. A general improvement of the OAR sparing was also observed. Conclusion: The lateral penumbra reduction afforded by the DCS increases the normal tissue sparing capabilities of PBS PT for brain cancer treatment while preserving target coverage.

  4. Theoretical Benefits of Dynamic Collimation in Pencil Beam Scanning Proton Therapy for Brain Tumors: Dosimetric and Radiobiological Metrics

    International Nuclear Information System (INIS)

    Moignier, Alexandra; Gelover, Edgar; Wang, Dongxu; Smith, Blake; Flynn, Ryan; Kirk, Maura; Lin, Liyong; Solberg, Timothy; Lin, Alexander; Hyer, Daniel

    2016-01-01

    Purpose: To quantify the dosimetric benefit of using a dynamic collimation system (DCS) for penumbra reduction during the treatment of brain tumors by pencil beam scanning proton therapy (PBS PT). Methods and Materials: Collimated and uncollimated brain treatment plans were created for 5 patients previously treated with PBS PT and retrospectively enrolled in an institutional review board–approved study. The in-house treatment planning system, RDX, was used to generate the plans because it is capable of modeling both collimated and uncollimated beamlets. The clinically delivered plans were reproduced with uncollimated plans in terms of target coverage and organ at risk (OAR) sparing to ensure a clinically relevant starting point, and collimated plans were generated to improve the OAR sparing while maintaining target coverage. Physical and biological comparison metrics, such as dose distribution conformity, mean and maximum doses, normal tissue complication probability, and risk of secondary brain cancer, were used to evaluate the plans. Results: The DCS systematically improved the dose distribution conformity while preserving the target coverage. The average reduction of the mean dose to the 10-mm ring surrounding the target and the healthy brain were 13.7% (95% confidence interval [CI] 11.6%-15.7%; P<.0001) and 25.1% (95% CI 16.8%-33.4%; P<.001), respectively. This yielded an average reduction of 24.8% (95% CI 0.8%-48.8%; P<.05) for the brain necrosis normal tissue complication probability using the Flickinger model, and 25.1% (95% CI 16.8%-33.4%; P<.001) for the risk of secondary brain cancer. A general improvement of the OAR sparing was also observed. Conclusion: The lateral penumbra reduction afforded by the DCS increases the normal tissue sparing capabilities of PBS PT for brain cancer treatment while preserving target coverage.

  5. The costs and benefits to participants in community partnerships: a paradox?

    Science.gov (United States)

    El Ansari, Walid; Phillips, Ceri J

    2004-01-01

    This article examines the degree of stakeholder participation in health and social partnership schemes in relation to their perceptions of benefits, costs, satisfaction, commitment, and ownership. The findings suggest that (a) involvement, commitment, and sense of ownership were invariably associated with high benefits and mostly with low costs; (b) benefits, commitment, and ownership might be more sensitive monitors of involvement than costs and satisfaction; (c) an increase in involvement was initially associated with decreased costs and increased satisfaction up to a point beyond which costs increased and satisfaction decreased despite increasing benefits; and (d) favorable cost-benefit ratios were perceived when the benefits were at least 1.6 times the costs. Partnership initiatives need to explore the involvement "cut-off" point at which the costs (and satisfaction) might change direction. For favorable cost-benefit ratios, benefits need to be at least 60% more than costs (Ansari's paradox).

  6. Improving heavy vehicle safety and road transport efficiency: a Performance-Based Standards approach in South Africa

    CSIR Research Space (South Africa)

    Nordengen, Paul A

    2018-04-01

    Full Text Available practical experience in the PBS approach and to quantify and evaluate the potential infrastructure preservation, safety and productivity benefits for road freight transport. To date, 450 permits for PBS demonstration vehicles (including 200 car...

  7. Univariate time series modeling and an application to future claims amount in SOCSO's invalidity pension scheme

    Science.gov (United States)

    Chek, Mohd Zaki Awang; Ahmad, Abu Bakar; Ridzwan, Ahmad Nur Azam Ahmad; Jelas, Imran Md.; Jamal, Nur Faezah; Ismail, Isma Liana; Zulkifli, Faiz; Noor, Syamsul Ikram Mohd

    2012-09-01

    The main objective of this study is to forecast the future claims amount of Invalidity Pension Scheme (IPS). All data were derived from SOCSO annual reports from year 1972 - 2010. These claims consist of all claims amount from 7 benefits offered by SOCSO such as Invalidity Pension, Invalidity Grant, Survivors Pension, Constant Attendance Allowance, Rehabilitation, Funeral and Education. Prediction of future claims of Invalidity Pension Scheme will be made using Univariate Forecasting Models to predict the future claims among workforce in Malaysia.

  8. A Systematic Scheme for Multiple Access in Ethernet Passive Optical Access Networks

    Science.gov (United States)

    Ma, Maode; Zhu, Yongqing; Hiang Cheng, Tee

    2005-11-01

    While backbone networks have experienced substantial changes in the last decade, access networks have not changed much. Recently, passive optical networks (PONs) seem to be ready for commercial deployment as access networks, due to the maturity of a number of enabling technologies. Among the PON technologies, Ethernet PON (EPON) standardized by the IEEE 802.3ah Ethernet in the First Mile (EFM) Task Force is the most attractive one because of its high speed, low cost, familiarity, interoperability, and low overhead. In this paper, we consider the issue of upstream channel sharing in the EPONs. We propose a novel multiple-access control scheme to provide bandwidth-guaranteed service for high-demand customers, while providing best effort service to low-demand customers according to the service level agreement (SLA). The analytical and simulation results prove that the proposed scheme performs best in what it is designed to do compared to another well-known scheme that has not considered providing differentiated services. With business customers preferring premium services with guaranteed bandwidth and residential users preferring low-cost best effort services, our scheme could benefit both groups of subscribers, as well as the operators.

  9. Achieving global environmental benefits through local development of clean energy? The case of small hilly hydel in India

    International Nuclear Information System (INIS)

    Reddy, V. Ratna; Uitto, Juha I.; Frans, Dirk R.; Matin, Nilufar

    2006-01-01

    Energy and development are closely intertwined. Yet, increasing fossil fuel-based energy consumption contributes significantly to environmental problems both locally and globally. This article explores the interlinkages between local livelihood and environmental benefits from the provision of energy to remote rural households through small hydropower development. The analysis is based on research carried out around a large development project designed to assist the Government of India in the optimum utilization of small hydropower resources in the Himalayan and sub-Himalayan regions. There are about 100,000 villages in India that are not connected to electricity supply, many of them in the hilly regions with ample hydropower potential. The project aimed to demonstrate the utility of and options for providing electricity to such villages through clean mini-hydro. The article addresses the nature of the impacts of the demonstration small hydel schemes on the local communities, to what extent they translate into environmental benefits both locally and globally, and the perceptions and participation of the local communities in these small hydro schemes. The study explores the impacts of the schemes on financial capital, natural capital, social capital, physical capital, human capital, and gender equity in the local communities. It further provides a discussion on the links between local and global environmental benefits. Overall, it is found that the schemes' impacts both on the local communities and the environment are mostly marginally positive or neutral, although achieving clearly demonstrable benefits would require major upscaling of the effort involving broader changes than possible under this project. Furthermore, it is argued that some of the assumptions behind the project design were faulty. Involvement of the local communities and direct livelihood benefits to them are essential for the long-term sustainability of the small hydro schemes. The discussion and

  10. Adaptive protection scheme

    Directory of Open Access Journals (Sweden)

    R. Sitharthan

    2016-09-01

    Full Text Available This paper aims at modelling an electronically coupled distributed energy resource with an adaptive protection scheme. The electronically coupled distributed energy resource is a microgrid framework formed by coupling the renewable energy source electronically. Further, the proposed adaptive protection scheme provides a suitable protection to the microgrid for various fault conditions irrespective of the operating mode of the microgrid: namely, grid connected mode and islanded mode. The outstanding aspect of the developed adaptive protection scheme is that it monitors the microgrid and instantly updates relay fault current according to the variations that occur in the system. The proposed adaptive protection scheme also employs auto reclosures, through which the proposed adaptive protection scheme recovers faster from the fault and thereby increases the consistency of the microgrid. The effectiveness of the proposed adaptive protection is studied through the time domain simulations carried out in the PSCAD⧹EMTDC software environment.

  11. Programming scheme based optimization of hybrid 4T-2R OxRAM NVSRAM

    Science.gov (United States)

    Majumdar, Swatilekha; Kingra, Sandeep Kaur; Suri, Manan

    2017-09-01

    In this paper, we present a novel single-cycle programming scheme for 4T-2R NVSRAM, exploiting pulse engineered input signals. OxRAM devices based on 3 nm thick bi-layer active switching oxide and 90 nm CMOS technology node were used for all simulations. The cell design is implemented for real-time non-volatility rather than last-bit, or power-down non-volatility. Detailed analysis of the proposed single-cycle, parallel RRAM device programming scheme is presented in comparison to the two-cycle sequential RRAM programming used for similar 4T-2R NVSRAM bit-cells. The proposed single-cycle programming scheme coupled with the 4T-2R architecture leads to several benefits such as- possibility of unconventional transistor sizing, 50% lower latency, 20% improvement in SNM and ∼20× reduced energy requirements, when compared against two-cycle programming approach.

  12. Comparative study of numerical schemes of TVD3, UNO3-ACM and optimized compact scheme

    Science.gov (United States)

    Lee, Duck-Joo; Hwang, Chang-Jeon; Ko, Duck-Kon; Kim, Jae-Wook

    1995-01-01

    Three different schemes are employed to solve the benchmark problem. The first one is a conventional TVD-MUSCL (Monotone Upwind Schemes for Conservation Laws) scheme. The second scheme is a UNO3-ACM (Uniformly Non-Oscillatory Artificial Compression Method) scheme. The third scheme is an optimized compact finite difference scheme modified by us: the 4th order Runge Kutta time stepping, the 4th order pentadiagonal compact spatial discretization with the maximum resolution characteristics. The problems of category 1 are solved by using the second (UNO3-ACM) and third (Optimized Compact) schemes. The problems of category 2 are solved by using the first (TVD3) and second (UNO3-ACM) schemes. The problem of category 5 is solved by using the first (TVD3) scheme. It can be concluded from the present calculations that the Optimized Compact scheme and the UN03-ACM show good resolutions for category 1 and category 2 respectively.

  13. VLSI Implementation of Hybrid Wave-Pipelined 2D DWT Using Lifting Scheme

    Directory of Open Access Journals (Sweden)

    G. Seetharaman

    2008-01-01

    Full Text Available A novel approach is proposed in this paper for the implementation of 2D DWT using hybrid wave-pipelining (WP. A digital circuit may be operated at a higher frequency by using either pipelining or WP. Pipelining requires additional registers and it results in more area, power dissipation and clock routing complexity. Wave-pipelining does not have any of these disadvantages but requires complex trial and error procedure for tuning the clock period and clock skew between input and output registers. In this paper, a hybrid scheme is proposed to get the benefits of both pipelining and WP techniques. In this paper, two automation schemes are proposed for the implementation of 2D DWT using hybrid WP on both Xilinx, San Jose, CA, USA and Altera FPGAs. In the first scheme, Built-in self-test (BIST approach is used to choose the clock skew and clock period for I/O registers between the wave-pipelined blocks. In the second approach, an on-chip soft-core processor is used to choose the clock skew and clock period. The results for the hybrid WP are compared with nonpipelined and pipelined approaches. From the implementation results, the hybrid WP scheme requires the same area but faster than the nonpipelined scheme by a factor of 1.25–1.39. The pipelined scheme is faster than the hybrid scheme by a factor of 1.15–1.39 at the cost of an increase in the number of registers by a factor of 1.78–2.73, increase in the number of LEs by a factor of 1.11–1.32 and it increases the clock routing complexity.

  14. Characteristics of individuals receiving disability benefits in the Netherlands and predictors of leaving the disability benefit scheme: a retrospective cohort study with five-year follow-up.

    Science.gov (United States)

    Louwerse, Ilse; Huysmans, Maaike A; van Rijssen, H Jolanda; van der Beek, Allard J; Anema, Johannes R

    2018-01-18

    Today, work disability is one of the greatest social and labour market challenges for policy makers in most OECD countries, where on average, about 6% of the working-age population relies on disability benefits. Understanding of factors associated with long-term work disability may be helpful to identify groups of individuals at risk for disability benefit entitlement or continuing eligibility, and to develop effective interventions for these groups. The purpose of this study is to provide insight into the main diagnoses of workers who qualify for disability benefits and how these diagnoses differ in age, gender and education. Using a five-year follow-up, we examined the duration of disability benefits and how durations differ among individuals with various characteristics. We performed a cohort study of 31,733 individuals receiving disability benefits from the Dutch Social Security Institute (SSI) with a five-year follow-up. Data were collected from SSI databases. Information about disorders was assessed by an insurance physician upon benefit application. These data were used to test for significant relationships among socio-demographics, main diagnoses and comorbidity, and disability benefit entitlement and continuing eligibility. Mental disorders were the most frequent diagnosis for individuals claiming work disability. Diagnoses differed among age groups and education categories. Mental disorders were the main diagnosis for work disability for younger and more highly educated individuals, and physical disorders (generally musculoskeletal, cardiovascular and cancer) were the main diagnosis for older and less educated individuals. In 82% of the claims, the duration of disability benefit was five years or more after approval. Outflow was lowest for individuals with (multiple) mental disorders and those with comorbidity of mental and physical disorders, and highest for individuals with (multiple) physical disorders. The main diagnosis for persons entitled to

  15. CAD for CT colonography: toward a preparation-independent scheme

    International Nuclear Information System (INIS)

    Naeppi, J.

    2007-01-01

    Computer-aided detection (CAD) systems can be used to automatically detect and display the locations of polyps and masses in computed tomographic colonography (CTC) data for assisting radiologists' image interpretation. Rapid technical advancements over the last few years have established a fundamental CAD scheme for CTC that includes the steps of colon extraction, polyp detection, and false-positive (FP) reduction. Several CAD prototype systems have demonstrated clinically acceptable high polyp detection sensitivity with relatively few FP detections in cathartic CTC, and observer studies have demonstrated the potential benefit of such systems in improving the accuracy and consistency of radiologists' detection performance. Some CAD prototype systems have also demonstrated promising performance in reduced cathartic and non-cathartic CTC. Recent advancements suggest that CAD systems can soon be expected to provide a preparation-independent scheme that can yield consistently high detection sensitivity with moderately low FP rate not only with cathartic CTC protocols but over a wide range of cathartic, reduced cathartic, and non-cathartic CTC protocols. (orig.)

  16. Toward High-Performance Coatings for Biomedical Devices: Study on Plasma-Deposited Fluorocarbon Films and Ageing in PBS

    Directory of Open Access Journals (Sweden)

    Diego Mantovani

    2010-03-01

    Full Text Available High performance coatings tailored to medical devices represent a recognised approach to modulate surface properties. Plasma-deposited fluorocarbon films have been proposed as a potential stent coating. Previous studies have shown promising adhesion properties: the 35 nm-thick film sustained plastic deformation up to 25% such as induced during the clinical implantation. In this study, the compositional and morphological changes of plasma-deposited fluorocarbon films were examined during ageing in a pseudo-physiological medium, a phosphate buffer solution (PBS, by angle-resolved XPS, FT-IR data and AFM images. The evolution of the ageing process is discussed: defluorination and crosslinking yielded an oxidized protective top layer onto the films, which showed further degradation.

  17. Performance of the Goddard multiscale modeling framework with Goddard ice microphysical schemes

    Science.gov (United States)

    Chern, Jiun-Dar; Tao, Wei-Kuo; Lang, Stephen E.; Matsui, Toshihisa; Li, J.-L. F.; Mohr, Karen I.; Skofronick-Jackson, Gail M.; Peters-Lidard, Christa D.

    2016-03-01

    The multiscale modeling framework (MMF), which replaces traditional cloud parameterizations with cloud-resolving models (CRMs) within a host atmospheric general circulation model (GCM), has become a new approach for climate modeling. The embedded CRMs make it possible to apply CRM-based cloud microphysics directly within a GCM. However, most such schemes have never been tested in a global environment for long-term climate simulation. The benefits of using an MMF to evaluate rigorously and improve microphysics schemes are here demonstrated. Four one-moment microphysical schemes are implemented into the Goddard MMF and their results validated against three CloudSat/CALIPSO cloud ice products and other satellite data. The new four-class (cloud ice, snow, graupel, and frozen drops/hail) ice scheme produces a better overall spatial distribution of cloud ice amount, total cloud fractions, net radiation, and total cloud radiative forcing than earlier three-class ice schemes, with biases within the observational uncertainties. Sensitivity experiments are conducted to examine the impact of recently upgraded microphysical processes on global hydrometeor distributions. Five processes dominate the global distributions of cloud ice and snow amount in long-term simulations: (1) allowing for ice supersaturation in the saturation adjustment, (2) three additional correction terms in the depositional growth of cloud ice to snow, (3) accounting for cloud ice fall speeds, (4) limiting cloud ice particle size, and (5) new size-mapping schemes for snow and graupel. Despite the cloud microphysics improvements, systematic errors associated with subgrid processes, cyclic lateral boundaries in the embedded CRMs, and momentum transport remain and will require future improvement.

  18. Wineries Evaluation of Costs and Benefits of Sustainability Certification Program: The Case of Terra Vitis in France.

    Science.gov (United States)

    Jourjon, Frederique; Chou, Hsia-Chi; Gezart, Anna; Kadison, Amy E; Martinat, Lea; Pomarici, Eugenio; Vecchio, Riccardo

    2016-01-01

    The current paper analyses the evaluation of the costs and benefits of French wineries (N=69) participating in the sustainability program Terra Vitis, a widespread environmental certification scheme within the French wine industry. An online questionnaire was sent to all Terra Vitis participants, in order to analyse the evaluation of economic costs and benefits (together with environmental benefits) as perceived by wineries. Our findings reveal that older participants in the scheme (over 5 years), firms with higher export share (>40% of annual turnover) and cooperative wineries tend to be keener to assign a positive evaluation to the benefits/costs ratio in both the vineyard and the winery. In the context of increasing concerns regarding the economic and environmental performance of the French agricultural sector, such findings and also the patent research could be useful for policy makers and entrepreneurs in defining mainstream normative and corporate strategies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Effect of precursors on the solid-state synthesis of semiconducting PbS nanostructures

    Directory of Open Access Journals (Sweden)

    Sujata Kasabe

    2013-03-01

    Full Text Available In this communication, we report facile and economical in-situ preparation of lead sulphide (PbS nanorods and nanocubes within the Polyphenylene sulphide (PPS matrix. PPS plays a dual role in the synthesis of the resultant nanostructures as - (i a chalcogen source and (ii a stabilizing matrix. We studied the effect of change of lead precursor from lead nitrate to acetate on the morphological properties of the resultant nanostructures. The effect of molar ratios of the reactants (1:1, 1:5, 1:10, 1:15 and 1:20 on the morphology of the products was also studied. The resultant nanocomposites were characterized by various physico-chemical techniques like X-ray Diffractometry (XRD, SEM equipped with EDAX, TEM and UV-Visible spectroscopy. The prima-facie observations suggest effective formation and subsequent entrapment of lead sulphide nanorods and nanocubes, respectively, when lead acetate and lead nitrate precursors were used. Additionally, simultaneous occurrence of nanocrystalline cubic lead as an impurity phase is noticed in case of heated admixtures for both the precursors.

  20. Interconnected TiO2 Nanowire Networks for PbS Quantum Dot Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Fan Xu

    2012-01-01

    Full Text Available We present a simple method for the fabrication of an interconnected porous TiO2 nanostructured film via dip coating in a colloidal suspension of ultrathin TiO2 nanowires followed by high-temperature annealing. The spheroidization of the nanowires and the fusing of the loosely packed nanowire films at the contact points lead to the formation of nanopores. Using this interconnected TiO2 nanowire network for electron transport, a PbS/TiO2 heterojunction solar cell with a large short-circuit current of 2.5 mA/cm2, a Voc of 0.6 V, and a power conversion efficiency of 5.4% is achieved under 8.5 mW/cm2 white light illumination. Compared to conventional planar TiO2 film structures, these results suggest superior electron transport properties while still providing the large interfacial area between PbS quantum dots and TiO2 required for efficient exciton dissociation.

  1. Patient access to new cancer drugs in the United States and Australia.

    Science.gov (United States)

    Wilson, Andrew; Cohen, Joshua

    2011-01-01

    In light of the current debate on the use value and potential impact of comparative effectiveness research on patient access, it may prove insightful to compare a health-care system that systematically bases its reimbursement decisions on comparative effectiveness evidence with the United States (US) system that hitherto has only been informed by such evidence on an ad hoc basis. For a set of 2000-2009 approved new molecular entities and biologics indicated for cancer, we compared patient access between US Medicare and Australian Pharmaceutical Benefits Scheme (PBS) beneficiaries. Here, access is defined in terms of marketing availability, payer coverage, and patient out-of-pocket costs. Although 34 drugs and biologics were approved for cancer in the US, just more than one-third (35%) were ultimately covered by the Australian PBS. The PBS also placed more restrictions on use. On the other hand, prices and patient out-of-pocket costs were greater for the US Medicare population. Our analysis points to a possible trade-off in market access to oncology drugs. Although more oncology drugs are available in the US and a higher percentage of available drugs are covered, the evidence-based approach adopted by Australia has contributed to reduced prices, thereby improving affordability for payers and patients for those medications deemed cost-effective by the reimbursement authority. Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  2. Sustainability Assessment of Large Irrigation Dams in Senegal: A Cost-Benefit Analysis for the Senegal River Valley

    Directory of Open Access Journals (Sweden)

    Stanislaw eManikowski

    2016-03-01

    Full Text Available Starting in the 1970s, the Senegalese Government invested in the development of irrigated schemes in the Senegalese part of the Senegal River Valley (S-SRV. From that time to 2012, the irrigated schemes increased from 10,000 ha to more than 110,000 ha. In the meantime, the economic viability of these schemes started to be questioned. It also appeared that the environmental health and social costs might outweigh the benefits of irrigation. Using a life cycle assessment approach and project cost-benefits modelling, this study (i quantified the costs and benefits of the S-SRV irrigated rice production, (ii evaluated the costs and benefits of its externalities and (iii discussed the irrigated rice support policy. The net financial revenues from the irrigated schemes were positive, but their economic equivalences. The economic return rate (EER was below the expected 12% and the net present value (NPV over 20 years of the project represented a loss of about US$-19.6 million. However, if we also include the project’s negative externalities, such as the reduced productivity of the valley ecosystems, protection cost of human health, environmental degradation and social impacts, then the NPV would be much worse, approximately US$-572.1 million. Therefore, the results show that to stop the economic loss and alleviate the human suffering, the S-SRV development policy should be revised using an integrated approach and the exploitation technology should aim at environmental sustainability. This paper may offer useful insights for reviewing the current Senegalese policies for the valley, as well as for assessing other similar cases or future projects worldwide, particularly in critical zones of developing countries.

  3. Socioeconomic and programmatic determinants of renewal of membership in a voluntary micro health insurance scheme: evidence from Chakaria, Bangladesh.

    Science.gov (United States)

    Iqbal, Mohammad; Chowdhury, Asiful Haidar; Mahmood, Shehrin Shaila; Mia, Mohammad Nahid; Hanifi, S M A; Bhuiya, Abbas

    2017-01-01

    Out-of-pocket (OOP) healthcare expenditure is a major obstacle for achieving universal health coverage in low-income countries including Bangladesh. Sixty-three percent of the USD 27 annual per-capita healthcare expenditure in Bangladesh comes from individuals' pockets. Although health insurance is a financial tool for reducing OOP, use of such tools in Bangladesh has been limited to some small-scale voluntary micro health insurance (MHI) schemes run by non-governmental organizations (NGO). The MHI, however, can orient people on health insurance concept and provide learning for product development, implementation, barriers to enrolment, membership renewal, and other operational challenges and solutions. Keeping this in mind, icddr,b in 2012 initiated a pilot MHI, Amader Shasthya, in Chakaria, Bangladesh. This paper explores the determinants of membership renewal in this scheme, which is a perpetual challenge for MHI. Identify socioeconomic and programmatic determinants and their effects on membership renewal in a voluntary MHI scheme. Data came from the online management information system of the scheme and Health and Demographic Surveillance System of Chakaria, covering the period February 2012-May 2015. Association between renewal and independent variables was examined using cross-tabular and logistic regression analyses. Nearly 20% of households in the catchment area ever enroled in the scheme, and 38% renewed membership over the initial 3 years of operation. Frequency of consultation with healthcare providers, benefits received, proximity of member's residence to health facility, socioeconomic status, educational level, and age of the household head showed significant positive association with renewal of membership. Villagers' enrolment in the scheme indicated that even in poor economic and literacy conditions people can be motivated to enrol in insurance schemes. Degree of service utilization and benefits received can greatly enhance the probability of

  4. Performance or marketing benefits? The case of LEED certification.

    Science.gov (United States)

    Matisoff, Daniel C; Noonan, Douglas S; Mazzolini, Anna M

    2014-01-01

    Green building adoption is driven by both performance-based benefits and marketing based benefits. Performance based benefits are those that improve performance or lower operating costs of the building or of building users. Marketing benefits stem from the consumer response to green certification. This study illustrates the relative importance of the marketing based benefits that accrue to Leadership in Energy and Environmental Design (LEED) buildings due to green signaling mechanisms, specifically related to the certification itself are identified. Of course, all participants in the LEED certification scheme seek marketing benefits. But even among LEED participants, the interest in green signaling is pronounced. The green signaling mechanism that occurs at the certification thresholds shifts building patterns from just below to just above the threshold level, and motivates builders to cluster buildings just above each threshold. Results are consistent across subsamples, though nonprofit organizations appear to build greener buildings and engage in more green signaling than for-profit entities. Using nonparametric regression discontinuity, signaling across different building types is observed. Marketing benefits due to LEED certification drives organizations to build "greener" buildings by upgrading buildings at the thresholds to reach certification levels.

  5. A New Pricing Scheme for Controlling Energy Storage Devices in Future Smart Grid

    Directory of Open Access Journals (Sweden)

    Jingwei Zhu

    2014-01-01

    Full Text Available Improvement of the overall efficiency of energy infrastructure is one of the main anticipated benefits of the deployment of smart grid technology. Advancement in energy storage technology and two-way communication in the electric network are indispensable components to achieve such a vision, while efficient pricing schemes and appropriate storage management are also essential. In this paper, we propose a universal pricing scheme which permits one to indirectly control the energy storage devices in the grid to achieve a more desirable aggregate demand profile that meets a particular target of the grid operator such as energy generation cost minimization and carbon emission reduction. Such a pricing scheme can potentially be applied to control the behavior of energy storage devices installed for integration of intermittent renewable energy sources that have permission to grid connection and will have broader applications as an increasing number of novel and low-cost energy storage technologies emerge.

  6. Efficient Asymmetric Index Encapsulation Scheme for Anonymous Content Centric Networking

    Directory of Open Access Journals (Sweden)

    Rong Ma

    2017-01-01

    Full Text Available Content Centric Networking (CCN is an effective communication paradigm that well matches the features of wireless environments. To be considered a viable candidate in the emerging wireless networks, despite the clear benefits of location-independent security, CCN must at least have parity with existing solutions for confidential and anonymous communication. This paper designs a new cryptographic scheme, called Asymmetric Index Encapsulation (AIE, that enables the router to test whether an encapsulated header matches the token without learning anything else about both of them. We suggest using the AIE as the core protocol of anonymous Content Centric Networking. A construction of AIE which strikes a balance between efficiency and security is given. The scheme is proved to be secure based on the DBDH assumption in the random oracle with tight reduction, while the encapsulated header and the token in our system consist of only three elements.

  7. Compensation schemes, liquidity provision, and asset prices: An experimental analysis

    OpenAIRE

    Baghestanian, Sascha; Gortner, Paul; Massenot, Baptiste

    2015-01-01

    In an experimental setting in which investors can entrust their money to traders, we investigate how compensation schemes affect liquidity provision and asset prices. Investors face a trade-off between risk and return. At the benefit of a potentially higher return, they can entrust their money to a trader. However this investment is risky, as the trader might not be trustworthy. Alternatively, they can opt for a safe but low return. We study how subjects solve this trade-off when traders are ...

  8. On the energy benefit of compute-and-forward on the hexagonal lattice

    NARCIS (Netherlands)

    Ren, Zhijie; Goseling, Jasper; Weber, Jos; Gastpar, Michael; Skoric, B.; Ignatenko, T.

    2014-01-01

    We study the energy benefit of applying compute-and-forward on a wireless hexagonal lattice network with multiple unicast sessions with a specific session placement. Two compute-and-forward based transmission schemes are proposed, which allow the relays to exploit both the broadcast and

  9. Colour schemes

    DEFF Research Database (Denmark)

    van Leeuwen, Theo

    2013-01-01

    This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation.......This chapter presents a framework for analysing colour schemes based on a parametric approach that includes not only hue, value and saturation, but also purity, transparency, luminosity, luminescence, lustre, modulation and differentiation....

  10. Benefit-feature segmentation: A tool for the design of a supply-chain strategy

    NARCIS (Netherlands)

    Canever, M.D.; Trijp, van J.C.M.; Lans, van der I.A.

    2007-01-01

    Abstract: Purpose ¿ This paper aims to assess the effectiveness of different segmentation schemes as the basis of marketing strategy, with particular respect to supply-chain decisions, and to propose a new procedure capable of combining benefits sought and features available.

  11. Silica coating of PbS quantum dots and their position control using a nanohole on Si substrate

    Science.gov (United States)

    Mukai, Kohki; Okumura, Isao; Nishizaki, Yuta; Yamashita, Shuzo; Niwa, Keisuke

    2018-04-01

    We succeeded in controlling the apparent size of a colloidal PbS quantum dot (QD) in the range of 20 to 140 nm by coating with silica and trapping the coated QDs in a nanohole prepared by scanning probe microscope lithography. Photoluminescence intensity was improved by controlling the process of adding the silica source material of tetraethoxysilane for the coating. Nanoholes of different sizes were formed on a single substrate by scanning probe oxidation with the combination of SF6 dry etching and KOH wet etching. QDs having an arbitrary energy structure can be arranged at an arbitrary position on the semiconductor substrate using this technique, which will aid in the fabrication of future nanosize solid devices such as quantum information circuits.

  12. Accounting for early action in the European Union Emission Trading Scheme

    International Nuclear Information System (INIS)

    Arto, Inaki; Gallastegui, Carmen; Ansuategi, Alberto

    2009-01-01

    In the context of emission markets, failure to include early action (EA) as a criterion when sharing out the reduction effort may be unfair. This paper presents (1) a method based on index decomposition that seeks to quantify EA and (2) a method for determining effort sharing considering EA. It is shown that, in the case of European industry (EU-15) and for the period 1995-2005, EA accounted for a reduction of 21% in energy-related CO 2 emissions. Considering two alternative schemes for sharing out the reduction effort in European industry, equal shares (all industries in all countries reduce their emissions by the same percentage) and taking EA into account, we find that Spain, Austria, Italy, the United Kingdom and Sweden would be better off under an equal shares scheme as opposed to one that takes EA into account. The efforts of the remaining countries would be greater than if EA was taken into account. An equal shares scheme would also greatly benefit the textile, non-metallic mineral, paper and 'other' industries, and would be particularly detrimental to the chemical, non-ferrous and other metal, and engineering industries.

  13. Accounting for early action in the European Union Emission Trading Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Arto, Inaki [IEP, Instituto de Economia Publica, University of the Basque Country, Avd. Lehendakari Agirre, 48015 Bilbao (Spain); Departamento de Fundamentos del Analisis Economico I, University of the Basque Country, Avd. Lehendakari Agirre, 48015 Bilbao (Spain); Gallastegui, Carmen [IEP, Instituto de Economia Publica, University of the Basque Country, Avd. Lehendakari Agirre, 48015 Bilbao (Spain); Ansuategi, Alberto [Departamento de Fundamentos del Analisis Economico I, University of the Basque Country, Avd. Lehendakari Agirre, 48015 Bilbao (Spain)

    2009-10-15

    In the context of emission markets, failure to include early action (EA) as a criterion when sharing out the reduction effort may be unfair. This paper presents (1) a method based on index decomposition that seeks to quantify EA and (2) a method for determining effort sharing considering EA. It is shown that, in the case of European industry (EU-15) and for the period 1995-2005, EA accounted for a reduction of 21% in energy-related CO{sub 2} emissions. Considering two alternative schemes for sharing out the reduction effort in European industry, equal shares (all industries in all countries reduce their emissions by the same percentage) and taking EA into account, we find that Spain, Austria, Italy, the United Kingdom and Sweden would be better off under an equal shares scheme as opposed to one that takes EA into account. The efforts of the remaining countries would be greater than if EA was taken into account. An equal shares scheme would also greatly benefit the textile, non-metallic mineral, paper and 'other' industries, and would be particularly detrimental to the chemical, non-ferrous and other metal, and engineering industries. (author)

  14. Macro-level integrated renewable energy production schemes for sustainable development

    International Nuclear Information System (INIS)

    Subhadra, Bobban G.

    2011-01-01

    The production of renewable clean energy is a prime necessity for the sustainable future existence of our planet. However, because of the resource-intensive nature, and other challenges associated with these new generation renewable energy sources, novel industrial frameworks need to be co-developed. Integrated renewable energy production schemes with foundations on resource sharing, carbon neutrality, energy-efficient design, source reduction, green processing plan, anthropogenic use of waste resources for the production green energy along with the production of raw material for allied food and chemical industries is imperative for the sustainable development of this sector especially in an emission-constrained future industrial scenario. To attain these objectives, the scope of hybrid renewable production systems and integrated renewable energy industrial ecology is briefly described. Further, the principles of Integrated Renewable Energy Park (IREP) approach, an example for macro-level energy production, and its benefits and global applications are also explored. - Research highlights: → Discusses the need for macro-level renewable energy production schemes. → Scope of hybrid and integrated industrial ecology for renewable energy production. → Integrated Renewable Energy Parks (IREPs): A macro-level energy production scheme. → Discusses the principle foundations and global applications of IREPs. → Describes the significance of IREPs in the carbon-neutral future business arena.

  15. Influence of grain size on structural and optic properties of PbS thin films produced by SILAR method

    International Nuclear Information System (INIS)

    Güneri, E.; Göde, F.; Çevik, S.

    2015-01-01

    In this the paper, we use the successive ion layer adsorption and reaction technique (SILAR) chemical deposition method to fabricate good quality PbS thin films and the effects of grain size on the structural and optical properties of the thin films were determined by varying deposition cases. All of the films obtained in different dipping cycles show cubic rock-salt (NaCl) structure. The preferred orientation changed from the (111) direction to the (200) direction with increasing dipping cycles. Grain size determined from scanning electron microscopy (SEM) increased from 32 nm to 104 nm. Moreover, changing of atomic ratio of the thin films is determined according to the results of energy dispersive X-ray (EDX). The transmission of the thin films was characterized by UV–Vis measurements from 400 nm to 1100 nm. It was determined from the allowed direct graphics that the energy band gaps of the thin films shift from 1.33 eV to 1.92 eV in connection with deposition conditions. The variation in band gap may be attributed to the variation of grain size. Additionally, the refractive index (n), extinction coefficient (k), real (ε 1 ) and imaginary (ε 2 ) dielectric constants varied with increasing immersion cycles. - Highlights: • The effects of grain size on the structural, optical properties of PbS thin films deposited by SILAR were investigated. • The preferred orientation varied from the (111) direction to the (200) direction with changing grain size. • The energy band gaps of the thin films shift from 1.33 eV to 1.92 eV in connection with deposition conditions. • The refractive index, extinction coefficient, real and imaginary dielectric constants varied with increasing dipping cycles

  16. Influence of grain size on structural and optic properties of PbS thin films produced by SILAR method

    Energy Technology Data Exchange (ETDEWEB)

    Güneri, E., E-mail: emineg7@gmail.com [Department of Primary Education, Erciyes University, Kayseri 38039, Turkey. (Turkey); Göde, F.; Çevik, S. [Department of Physics, Mehmet Akif Ersoy University, Burdur 15030, Turkey. (Turkey)

    2015-08-31

    In this the paper, we use the successive ion layer adsorption and reaction technique (SILAR) chemical deposition method to fabricate good quality PbS thin films and the effects of grain size on the structural and optical properties of the thin films were determined by varying deposition cases. All of the films obtained in different dipping cycles show cubic rock-salt (NaCl) structure. The preferred orientation changed from the (111) direction to the (200) direction with increasing dipping cycles. Grain size determined from scanning electron microscopy (SEM) increased from 32 nm to 104 nm. Moreover, changing of atomic ratio of the thin films is determined according to the results of energy dispersive X-ray (EDX). The transmission of the thin films was characterized by UV–Vis measurements from 400 nm to 1100 nm. It was determined from the allowed direct graphics that the energy band gaps of the thin films shift from 1.33 eV to 1.92 eV in connection with deposition conditions. The variation in band gap may be attributed to the variation of grain size. Additionally, the refractive index (n), extinction coefficient (k), real (ε{sub 1}) and imaginary (ε{sub 2}) dielectric constants varied with increasing immersion cycles. - Highlights: • The effects of grain size on the structural, optical properties of PbS thin films deposited by SILAR were investigated. • The preferred orientation varied from the (111) direction to the (200) direction with changing grain size. • The energy band gaps of the thin films shift from 1.33 eV to 1.92 eV in connection with deposition conditions. • The refractive index, extinction coefficient, real and imaginary dielectric constants varied with increasing dipping cycles.

  17. Socio-ecological impact of development schemes in the homelands of South Africa

    Energy Technology Data Exchange (ETDEWEB)

    de Wet, C. (Rhodes Univ., Grahamstown (South Africa))

    Development schemes in rural areas have a significant ecological impact as they often involve a reorganization of land-use and resource-utilization patterns. This reorganization is usually intended to have a positive ecological effect by combating erosion, promoting rational land-use patterns and using the potential of the area to best effect, thereby also providing economic benefits to the people living there. Often development schemes have the opposite effect - a negative ecological and economic impact as well as causing considerable social disruption, which in its turn has further negative ecological consequences. This paper looks at several kinds of development projects, seeking to understand why they have limited rather than increased ecological, economic and social options, and to what extent such negative effects can be avoided in future development projects in rural areas.

  18. Cryptanalysis of Three Password-Based Remote User Authentication Schemes with Non-Tamper-Resistant Smart Card

    Directory of Open Access Journals (Sweden)

    Chenyu Wang

    2017-01-01

    Full Text Available Remote user authentication is the first step to guarantee the security of online services. Online services grow rapidly and numerous remote user authentication schemes were proposed with high capability and efficiency. Recently, there are three new improved remote user authentication schemes which claim to be resistant to various attacks. Unfortunately, according to our analysis, these schemes all fail to achieve some critical security goals. This paper demonstrates that they all suffer from offline dictionary attack or fail to achieve forward secrecy and user anonymity. It is worth mentioning that we divide offline dictionary attacks into two categories: (1 the ones using the verification from smart cards and (2 the ones using the verification from the open channel. The second is more complicated and intractable than the first type. Such distinction benefits the exploration of better design principles. We also discuss some practical solutions to the two kinds of attacks, respectively. Furthermore, we proposed a reference model to deal with the first kind of attack and proved its effectiveness by taking one of our cryptanalysis schemes as an example.

  19. The impact of the healthcare system in Barbados (provision of health insurance and the benefit service scheme) on the use of herbal remedies by Christian churchgoers.

    Science.gov (United States)

    Cohall, D H; Scantlebury-Manning, T; Cadogan-McLean, C; Lallement, A; Willis-O'Connor, S

    2012-06-01

    To determine the impact of health insurance and the government's Benefit Service Scheme, a system that provides free drugs to treat mostly chronic illnesses to persons aged 16 to 65 years, on the use of herbal remedies by Christian churchgoers in Barbados. The eleven parishes of Barbados were sampled over a six-week period using a survey instrument developed and tested over a four-week period prior to administration. Persons were asked to participate and after written informed consent, they were interviewed by the research team. The data were analysed by the use of IBM SPSS version 19. The data were all nominal, so descriptive statistics including counts, the frequencies, odds ratios and percentages were calculated. More than half of the participants (59.2%) were female, a little less than a third (29.9%) were male, and one tenth of the participants (10.9%) did not indicate their gender The majority of the participants were between the ages of 41 and 70 years, with the age range of 51-60 years comprising 26.1% of the sample interviewed. Almost all of the participants were born in Barbados (92.5%). Approximately 33% of the respondents indicated that they used herbal remedies to treat various ailments including chronic conditions. The odds ratio of persons using herbal remedies and having health insurance to persons not using herbal remedies and having health insurance is 1.01 (95% CI 0.621, 1.632). There was an increase in the numbers of respondents using herbal remedies as age increased. This trend continued until the age group 71-80 years which showed a reduction in the use of herbal remedies, 32.6% of respondents compared with 38.3% of respondents in the 61-70-year category. The data demonstrated that only a third of the study population is using herbal remedies for ailments. Health insurance was not an indicator neither did it influence the use of herbal remedies by respondents. The use of herbal remedies may not be associated with affluence. The reduction in

  20. Medicines and the media: news reports of medicines recommended for government reimbursement in Australia.

    Science.gov (United States)

    Robertson, Jane; Walkom, Emily J; Bevan, Marc D; Newby, David A

    2013-05-21

    Previous analyses of the listings of trastuzumab on the Australian Pharmaceutical Benefits Scheme (PBS) and HPV vaccine on the National Immunisation Program (NIP) suggest a media influence on policy makers. We examined the timing and content of Australian newspaper reports of medicines in relation to Pharmaceutical Benefits Advisory Committee (PBAC) decisions. We identified newspaper reports (2005-2008) of medicines recommended for PBS listing in 2006-2007, analysing the content for mentions of the medicine, PBS and medicine costs to the patient and the government and counting the numbers of articles published in the six months before, the month of, and the six months after the relevant PBAC meeting. Case studies examined reporting for infliximab for Crohn's Disease, pemetrexed for mesothelioma, and ADHD (Attention Deficit Hyperactivity Disorder) medicines atomoxetine and methylphenidate. Of 79 eligible medicines, 62 had news reports. Most often reported were HPV vaccine (1230 stories), trastuzumab (410), pemetrexed (83), botulinum toxin (71), lapatinib (65), methylphenidate (57), atomoxetine (54), infliximab (49), rotavirus vaccine (45). Eighteen medicines had ≥20 news reports (total 2350 stories); nine of these cost more than AU$10,000 per course or year of treatment. For these 18 medicines, 31% of stories appeared in the six months prior to the PBAC meeting, 14% in the meeting month and 33% in the six months post-meeting. 38% of the stories had ≥3 medicine mentions, 37% referred to the PBS, 24% to cost to the patient, and 9% cost to Government.There was active patient lobby group campaigning in support of listing of infliximab and pemetrexed; the stories for ADHD were often more negative, referring to the dangers of the medicines and sometimes questioning the appropriateness of treatment and public subsidy. There was little discussion of the PBAC's evidence-based decision-making processes. While there was no general trend to increased news reporting

  1. The UKNEQAS scheme for cerebrospinal fluid haem pigments: a paradigm for service improvement.

    Science.gov (United States)

    Beetham, Robert; Egner, William; Patel, Dina

    2011-11-01

    We describe the programme of an established External Quality Assurance (EQA) provider and a Specialist Advisory Group (SAG) to develop a successful EQA scheme for cerebrospinal fluid (CSF) haem pigments as an example of a professionally led, unfunded initiative with the real potential to benefit patients. Within three years, we had assured sample stability, stoichiometry, and published best practice guidelines, enabling both analytical results and interpretation to be assessed and reported with an educative summary of the desired responses. Misclassification scoring of analysis and interpretation was introduced. Following audit, guidelines were modified and republished. The outcomes were as follows: Participant numbers increased from 63 at inception to 150 10 years later; The percentage of participants using visual inspection, a poor practice indicator, decreased from 27% to less than 1%; In all, 94-100% of participants consistently detected minor increases in bilirubin over the last four years of the scheme; More than 93% of participants were able to interpret analytical results linked to straightforward clinical scenarios; Misclassification scoring demonstrated that more complex scenarios repeatedly posed problems and is the next challenge to address. Scheme success is attributed to the experience of the operator and the formation of a voluntary expert advisory group, with both concerned to advance science and patient safety and thus contribute unpaid time and effort in order to succeed. In times of fiscal constraint, such resource may not be so readily available, yet is a vital part of continuous quality improvement for the benefit of patients.

  2. LevelScheme: A level scheme drawing and scientific figure preparation system for Mathematica

    Science.gov (United States)

    Caprio, M. A.

    2005-09-01

    LevelScheme is a scientific figure preparation system for Mathematica. The main emphasis is upon the construction of level schemes, or level energy diagrams, as used in nuclear, atomic, molecular, and hadronic physics. LevelScheme also provides a general infrastructure for the preparation of publication-quality figures, including support for multipanel and inset plotting, customizable tick mark generation, and various drawing and labeling tasks. Coupled with Mathematica's plotting functions and powerful programming language, LevelScheme provides a flexible system for the creation of figures combining diagrams, mathematical plots, and data plots. Program summaryTitle of program:LevelScheme Catalogue identifier:ADVZ Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVZ Operating systems:Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux Programming language used:Mathematica 4 Number of bytes in distributed program, including test and documentation:3 051 807 Distribution format:tar.gz Nature of problem:Creation of level scheme diagrams. Creation of publication-quality multipart figures incorporating diagrams and plots. Method of solution:A set of Mathematica packages has been developed, providing a library of level scheme drawing objects, tools for figure construction and labeling, and control code for producing the graphics.

  3. Certification and equity: Applying an “equity framework” to compare certification schemes across product sectors and scales

    International Nuclear Information System (INIS)

    McDermott, Constance L.

    2013-01-01

    Highlights: ► Assessing equity requires a comprehensive conceptual framework. ► The framing of equity varies across sectors and schemes. ► Schemes vary in prioritizing the environment, communities or equity in the supply chain. ► Addressing contextual equity is essential lest certification reinforce inequities of global trade. -- Abstract: This paper applies a comprehensive equity framework to compare the priorities and trade-offs of different environmental and social certification schemes. The schemes selected for comparison are the Forest Stewardship Council (FSC), the Programme for the Endorsement of Forest Certification Schemes (PEFC), the Fairtrade Labelling Organization (FLO), and the Climate, Community and Biodiversity Alliance (CCBA). The framework considers how the parameters of equity are set in certification scheme governance, including who are the primary decision-makers and intended beneficiaries, and how this is reflected in the content of scheme standards and certification outcomes. Each of these parameters is assessed across the dimensions of procedural, contextual and distributive equity. Results reveal significant variation in the prioritization of the environment, non-commercial stakeholders or equity across the supply chain. In forestry, the FSC has placed primary emphasis on the procedural rights of non-commercial interests in standard-setting processes, the contextual rights of indigenous peoples, and the conservation of natural ecosystems, while the PEFC places more emphasis on procedural equity for producers and the legitimacy of sovereign governments as rule-makers. Both FLO and CCBA prioritize distributive equity regarding the sharing of material benefits with small-scale and/or community producers or workers, while FLO also emphasizes the contextual issue of “empowerment” and capacity-building. In all schemes, contextual factors related to capacity and access have disproportionately advantaged Northern and large

  4. EUROPEAN DEVELOPMENT OF ECO‐MANAGEMENT AND AUDIT SCHEME (EMAS IN THE EUROPEAN UNION

    Directory of Open Access Journals (Sweden)

    Justyna SŁONIMIEC

    2013-10-01

    Full Text Available The paper presents the implementation of the Environmental Management and Audit Scheme System (EMAS in Poland and the European Union. It analyzes the existing rules on the implementation and the process of its implementation. It also defines the benefits and costs arising from the registration of organizations in the system. The paper presents the current status of implementation of EMAS in the European Union.

  5. Analysis of energy efficiency retrofit schemes for heating, ventilating and air-conditioning systems in existing office buildings based on the modified bin method

    International Nuclear Information System (INIS)

    Wang, Zhaoxia; Ding, Yan; Geng, Geng; Zhu, Neng

    2014-01-01

    Highlights: • A modified bin method is adopted to propose and optimize the EER schemes. • A case study is presented to demonstrate the analysis procedures of EER schemes. • Pertinent EER schemes for HVAC systems are proposed for the object building. - Abstract: Poor thermal performance of building envelop and low efficiencies of heating, ventilating and air-conditioning (HVAC) systems can always be found in the existing office buildings with large energy consumption. This paper adopted a modified bin method to propose and optimize the energy efficiency retrofit (EER) schemes. An existing office building in Tianjin was selected as an example to demonstrate the procedures of formulating the design scheme. Pertinent retrofit schemes for HVAC system were proposed after the retrofit of building envelop. With comprehensive consideration of energy efficiency and economic benefits, the recommended scheme that could improve the overall energy efficiency by 71.20% was determined

  6. Expanding Canada Pension Plan Retirement Benefits: Assessing Big CPP Proposals

    Directory of Open Access Journals (Sweden)

    Jonathan R. Kesselman

    2010-10-01

    Full Text Available Current and growing deficiencies in many workers’ ability to maintain their accustomed living standards in retirement have evoked varied proposals for reform of Canada’s retirement income system. This study focuses on proposals for expanding the retirement benefits of the Canada Pension Plan (CPP, and undertakes comparative analysis with proposals for reforms affecting workplace pensions and individual savings. It begins by reviewing key policy questions for the retirement income system and describing essential features of several proposals for CPP benefit expansion. It then uses these “Big CPP” proposals as a basis to assess the design issues for expanding CPP benefits and the implications for other components of the retirement income system. The paper assesses each of the major private and public savings vehicles based on multifaceted criteria for a well-performing retirement income system; a mandatory public scheme with defined benefits ranks most highly on almost all criteria other than individual flexibility. Additional behavioural and institutional factors also support the use of mandatory public pensions: myopia in savings, individual investment behaviour, scale economies and costs of fund management, adverse selection and annuitization costs, the Samaritan’s Dilemma, and labour market incentives. The study provides an overview analysis of key design issues for the expansion of CPP retirement benefits. Major issues include the desirable scale of expansion for both the percentage of insurable earnings and the insurable earnings ceiling; mandatory versus voluntary coverage and options; the allocation of investment return risk; and the phasing-in of higher premiums and benefits. The study then assesses the implications of CPP expansion for other components of the retirement income system: Old Age Security and the Guaranteed Income Supplement, workplace pensions, tax provisions for savings, and individual savings. A Big CPP fits

  7. Analysis of multi drug resistant tuberculosis (MDR-TB) financial protection policy: MDR-TB health insurance schemes, in Chhattisgarh state, India.

    Science.gov (United States)

    Kundu, Debashish; Sharma, Nandini; Chadha, Sarabjit; Laokri, Samia; Awungafac, George; Jiang, Lai; Asaria, Miqdad

    2018-01-27

    There are significant financial barriers to access treatment for multi drug resistant tuberculosis (MDR-TB) in India. To address these challenges, Chhattisgarh state in India has established a MDR-TB financial protection policy by creating MDR-TB benefit packages as part of the universal health insurance scheme that the state has rolled out in their effort towards attaining Universal Health Coverage for all its residents. In these schemes the state purchases health insurance against set packages of services from third party health insurance agencies on behalf of all its residents. Provider payment reform by strategic purchasing through output based payments (lump sum fee is reimbursed as per the MDR-TB benefit package rates) to the providers - both public and private health facilities empanelled under the insurance scheme was the key intervention. To understand the implementation gap between policy and practice of the benefit packages with respect to equity in utilization of package claims by the poor patients in public and private sector. Data from primary health insurance claims from January 2013 to December 2015, were analysed using an extension of 'Kingdon's multiple streams for policy implementation framework' to explain the implementation gap between policy and practice of the MDR-TB benefit packages. The total number of claims for MDR-TB benefit packages increased over the study period mainly from poor patients treated in public facilities, particularly for the pre-treatment evaluation and hospital stay packages. Variations and inequities in utilizing the packages were observed between poor and non-poor beneficiaries in public and private sector. Private providers participation in the new MDR-TB financial protection mechanism through the universal health insurance scheme was observed to be much lower than might be expected given their share of healthcare provision overall in India. Our findings suggest that there may be an implementation gap due to weak

  8. Enhanced interfacial contact between PbS and TiO2 layers in quantum dot solar cells using 2D-arrayed TiO2 hemisphere nanostructures

    Science.gov (United States)

    Lee, Wonseok; Ryu, Ilhwan; Lee, Haein; Yim, Sanggyu

    2018-02-01

    Two-dimensionally (2D) arrayed hemispherical nanostructures of TiO2 thin films were successfully fabricated using a simple procedure of spin-coating or dip-coating TiO2 nanoparticles onto 2D close-packed polystyrene (PS) nanospheres, followed by PS extraction. The nanostructured TiO2 film was then used as an n-type layer in a lead sulfide (PbS) colloidal quantum dot solar cell. The TiO2 nanostructure could provide significantly increased contacts with subsequently deposited PbS quantum dot layer. In addition, the periodically arrayed nanostructure could enhance optical absorption of the cell by redirecting the path of the incident light and increasing the path length passing though the active layer. As a result, the power conversion efficiency (PCE) reached 5.13%, which is approximately a 1.7-fold increase over that of the control cell without nanostructuring, 3.02%. This PCE enhancement can mainly be attributed to the increase of the short-circuit current density from 19.6 mA/cm2 to 30.6 mA/cm2, whereas the open-circuit voltage and fill factor values did not vary significantly.

  9. Packet reversed packet combining scheme

    International Nuclear Information System (INIS)

    Bhunia, C.T.

    2006-07-01

    The packet combining scheme is a well defined simple error correction scheme with erroneous copies at the receiver. It offers higher throughput combined with ARQ protocols in networks than that of basic ARQ protocols. But packet combining scheme fails to correct errors when the errors occur in the same bit locations of two erroneous copies. In the present work, we propose a scheme that will correct error if the errors occur at the same bit location of the erroneous copies. The proposed scheme when combined with ARQ protocol will offer higher throughput. (author)

  10. Secure and Efficient Two-Factor User Authentication Scheme with User Anonymity for Network Based E-Health Care Applications.

    Science.gov (United States)

    Li, Xiong; Niu, Jianwei; Karuppiah, Marimuthu; Kumari, Saru; Wu, Fan

    2016-12-01

    Benefited from the development of network and communication technologies, E-health care systems and telemedicine have got the fast development. By using the E-health care systems, patient can enjoy the remote medical service provided by the medical server. Medical data are important privacy information for patient, so it is an important issue to ensure the secure of transmitted medical data through public network. Authentication scheme can thwart unauthorized users from accessing services via insecure network environments, so user authentication with privacy protection is an important mechanism for the security of E-health care systems. Recently, based on three factors (password, biometric and smart card), an user authentication scheme for E-health care systems was been proposed by Amin et al., and they claimed that their scheme can withstand most of common attacks. Unfortunate, we find that their scheme cannot achieve the untraceability feature of the patient. Besides, their scheme lacks a password check mechanism such that it is inefficient to find the unauthorized login by the mistake of input a wrong password. Due to the same reason, their scheme is vulnerable to Denial of Service (DoS) attack if the patient updates the password mistakenly by using a wrong password. In order improve the security level of authentication scheme for E-health care application, a robust user authentication scheme with privacy protection is proposed for E-health care systems. Then, security prove of our scheme are analysed. Security and performance analyses show that our scheme is more powerful and secure for E-health care systems when compared with other related schemes.

  11. A scheme for a future distribution automation system in Finnish utilities

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M.; Kaerkkaeinen, S. [VTT Energy, Espoo (Finland); Partanen, J. [Lappeenranta Univ. of Technology (Finland)

    1996-12-31

    This presentation summarizes the results of a project, the aim of which was to define the optimal set of functions for the future distribution automation (DA) systems in Finland. The general factors. which affect the automation needs, are first discussed. The benefits of various functions of DA and demand side management (DSM) are then studied. Next a computer model for a DA feasibility analysis is presented, and some computation results are given. From these. the proposed automation scheme is finally concluded

  12. A scheme for a future distribution automation system in Finnish utilities

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M; Kaerkkaeinen, S [VTT Energy, Espoo (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1998-08-01

    This presentation summarizes the results of a project, the aim of which was to define the optimal set of functions for the future distribution automation (DA) systems in Finland. The general factors, which affect the automation needs, are first discussed. The benefits of various functions of DA and demand side management (DSM) are then studied. Next a computer model for a DA feasibility analysis is presented, and some computation results are given. From these, the proposed automation scheme is finally concluded

  13. A scheme for a future distribution automation system in Finnish utilities

    Energy Technology Data Exchange (ETDEWEB)

    Lehtonen, M; Kaerkkaeinen, S [VTT Energy, Espoo (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1997-12-31

    This presentation summarizes the results of a project, the aim of which was to define the optimal set of functions for the future distribution automation (DA) systems in Finland. The general factors. which affect the automation needs, are first discussed. The benefits of various functions of DA and demand side management (DSM) are then studied. Next a computer model for a DA feasibility analysis is presented, and some computation results are given. From these. the proposed automation scheme is finally concluded

  14. Development of Dalaelven hydro power scheme in Sweden

    International Nuclear Information System (INIS)

    Kokko, Voitto; Hjerthen, Peter; Ingfaelt, Hans; Loewen, Karl-Erik; Sjoegren, Arne

    2015-01-01

    The Dalaelven hydro scheme is located in central Sweden. Fortum has in the scheme 50 dams and 35 hydro power plants producing 4 TWh energy with a capacity of 970 MW. The main reservoirs are Lake Siljan and Traengsletsjoen with Traengslet dam, the highest earth-filled dam in Sweden. Development of the hydro scheme started 1878 with construction of four power plants for industry until 1930. From 1931 to 1974 15 power plants were built for increasing electricity consumption. De-regulation of the energy market in 1990's and EU environmental targets in 2000's resulted in the rehabilitation of ten power plants between 1990 and 2014 with increased annual energy production of 377 GWh (29%) and capacity 124 MW (59%). This energy decreases the annual CO 2 emissions with 125918 tons in comparison to production of the same amount of energy by coal. In several cases the rehabilitation was made in new power houses, allowing the development of the layout and technology of civil structures, and use of state-of-art equipment. Sweden uses the green certificate system, and 235 GWh of the energy received this certificate. Other environmental benefits come from use of the environmentally friendly Kaplan turbines and construction of some new fish pass. There are further plans to increase the spillway capacity of Traengslet dam and to rehabilitate eight power plant units. The possibilities of obtaining the Environmental licences for the rehabilitations has became challenging in the past years and green certificates are nowadays agreed only for increased energy. (authors)

  15. A full quantum network scheme

    International Nuclear Information System (INIS)

    Ma Hai-Qiang; Wei Ke-Jin; Yang Jian-Hui; Li Rui-Xue; Zhu Wu

    2014-01-01

    We present a full quantum network scheme using a modified BB84 protocol. Unlike other quantum network schemes, it allows quantum keys to be distributed between two arbitrary users with the help of an intermediary detecting user. Moreover, it has good expansibility and prevents all potential attacks using loopholes in a detector, so it is more practical to apply. Because the fiber birefringence effects are automatically compensated, the scheme is distinctly stable in principle and in experiment. The simple components for every user make our scheme easier for many applications. The experimental results demonstrate the stability and feasibility of this scheme. (general)

  16. Farmer Attitudes and Livestock Disease: Exploring Citizenship Behaviour and Peer Monitoring across Two BVD Control Schemes in the UK.

    Science.gov (United States)

    Heffernan, Claire; Azbel-Jackson, Lena; Brownlie, Joe; Gunn, George

    2016-01-01

    The eradication of BVD in the UK is technically possible but appears to be socially untenable. The following study explored farmer attitudes to BVD control schemes in relation to advice networks and information sharing, shared aims and goals, motivation and benefits of membership, notions of BVD as a priority disease and attitudes toward regulation. Two concepts from the organisational management literature framed the study: citizenship behaviour where actions of individuals support the collective good (but are not explicitly recognised as such) and peer to peer monitoring (where individuals evaluate other's behaviour). Farmers from two BVD control schemes in the UK participated in the study: Orkney Livestock Association BVD Eradication Scheme and Norfolk and Suffolk Cattle Breeders Association BVD Eradication Scheme. In total 162 farmers participated in the research (109 in-scheme and 53 out of scheme). The findings revealed that group helping and information sharing among scheme members was low with a positive BVD status subject to social censure. Peer monitoring in the form of gossip with regard to the animal health status of other farms was high. Interestingly, farmers across both schemes supported greater regulation with regard to animal health, largely due to the mistrust of fellow farmers following voluntary disease control measures. While group cohesiveness varied across the two schemes, without continued financial inducements, longer-term sustainability is questionable.

  17. Farmer Attitudes and Livestock Disease: Exploring Citizenship Behaviour and Peer Monitoring across Two BVD Control Schemes in the UK.

    Directory of Open Access Journals (Sweden)

    Claire Heffernan

    Full Text Available The eradication of BVD in the UK is technically possible but appears to be socially untenable. The following study explored farmer attitudes to BVD control schemes in relation to advice networks and information sharing, shared aims and goals, motivation and benefits of membership, notions of BVD as a priority disease and attitudes toward regulation. Two concepts from the organisational management literature framed the study: citizenship behaviour where actions of individuals support the collective good (but are not explicitly recognised as such and peer to peer monitoring (where individuals evaluate other's behaviour. Farmers from two BVD control schemes in the UK participated in the study: Orkney Livestock Association BVD Eradication Scheme and Norfolk and Suffolk Cattle Breeders Association BVD Eradication Scheme. In total 162 farmers participated in the research (109 in-scheme and 53 out of scheme. The findings revealed that group helping and information sharing among scheme members was low with a positive BVD status subject to social censure. Peer monitoring in the form of gossip with regard to the animal health status of other farms was high. Interestingly, farmers across both schemes supported greater regulation with regard to animal health, largely due to the mistrust of fellow farmers following voluntary disease control measures. While group cohesiveness varied across the two schemes, without continued financial inducements, longer-term sustainability is questionable.

  18. Transmission usage cost allocation schemes

    International Nuclear Information System (INIS)

    Abou El Ela, A.A.; El-Sehiemy, R.A.

    2009-01-01

    This paper presents different suggested transmission usage cost allocation (TCA) schemes to the system individuals. Different independent system operator (ISO) visions are presented using the proportional rata and flow-based TCA methods. There are two proposed flow-based TCA schemes (FTCA). The first FTCA scheme generalizes the equivalent bilateral exchanges (EBE) concepts for lossy networks through two-stage procedure. The second FTCA scheme is based on the modified sensitivity factors (MSF). These factors are developed from the actual measurements of power flows in transmission lines and the power injections at different buses. The proposed schemes exhibit desirable apportioning properties and are easy to implement and understand. Case studies for different loading conditions are carried out to show the capability of the proposed schemes for solving the TCA problem. (author)

  19. Benefit packages for chronic disease outpatients in the New Rural Cooperative Medical Scheme in 32 Chinese counties [v1; ref status: indexed, http://f1000r.es/z2

    Directory of Open Access Journals (Sweden)

    Chuangzhou Xu

    2013-06-01

    Full Text Available Introduction: Chronic disease has become a major problem affecting the health of the Chinese population. In response to this situation, the New Rural Cooperative Medical Scheme (NRCMS has begun to provide health cover for outpatients with chronic disease expenses, made possible by the increased risk pool of previous years. We compare the differences between Benefit Packages for Chronic Diseases Outpatients (BPCDO in order to produce a reference for policy makers. Methods: Information on the various BPCDO was located by searching the official NRCMS website in Chinese, using certain criteria to select the ideal BPCDO. Population coverage, service coverage and cost of coverage were chosen to form the analytical framework for this paper. The diseases were classified according to the World Health Organisation's (WHO International Classification of Diseases (ICD-10. Results: To avoid “moral hazard”, complex processes have been created. This has resulted in chronic disease patients finding it very difficult to become beneficiaries. Forty-one types of chronic diseases were listed in 32 different BPCDO. We found that different counties have different co-payment rates, deductible lines, ceilings, coverage of drugs and tests, appointed hospitals and reimbursement frequencies. Conclusion: High mortality diseases and diseases with a heavier cost burden should be the priority on the list of reimbursement. The BPCDO scheme should be introduced urgently at the national level. It should include twenty-one types of disease and eight essential factors.

  20. Benefits of incorporating the adaptive dynamic range optimization amplification scheme into an assistive listening device for people with mild or moderate hearing loss.

    Science.gov (United States)

    Chang, Hung-Yue; Luo, Ching-Hsing; Lo, Tun-Shin; Chen, Hsiao-Chuan; Huang, Kuo-You; Liao, Wen-Huei; Su, Mao-Chang; Liu, Shu-Yu; Wang, Nan-Mai

    2017-08-28

    This study investigated whether a self-designed assistive listening device (ALD) that incorporates an adaptive dynamic range optimization (ADRO) amplification strategy can surpass a commercially available monaurally worn linear ALD, SM100. Both subjective and objective measurements were implemented. Mandarin Hearing-In-Noise Test (MHINT) scores were the objective measurement, whereas participant satisfaction was the subjective measurement. The comparison was performed in a mixed design (i.e., subjects' hearing status being mild or moderate, quiet versus noisy, and linear versus ADRO scheme). The participants were two groups of hearing-impaired subjects, nine mild and eight moderate, respectively. The results of the ADRO system revealed a significant difference in the MHINT sentence reception threshold (SRT) in noisy environments between monaurally aided and unaided conditions, whereas the linear system did not. The benchmark results showed that the ADRO scheme is effectively beneficial to people who experience mild or moderate hearing loss in noisy environments. The satisfaction rating regarding overall speech quality indicated that the participants were satisfied with the speech quality of both ADRO and linear schemes in quiet environments, and they were more satisfied with ADRO than they with the linear scheme in noisy environments.

  1. User experience with a health insurance coverage and benefit-package access: implications for policy implementation towards expansion in Nigeria.

    Science.gov (United States)

    Mohammed, Shafiu; Aji, Budi; Bermejo, Justo Lorenzo; Souares, Aurelia; Dong, Hengjin; Sauerborn, Rainer

    2016-04-01

    Developing countries are devising strategies and mechanisms to expand coverage and benefit-package access for their citizens through national health insurance schemes (NHIS). In Nigeria, the scheme aims to provide affordable healthcare services to insured-persons and their dependants. However, inclusion of dependants is restricted to four biological children and a spouse per user. This study assesses the progress of implementation of the NHIS in Nigeria, relating to coverage and benefit-package access, and examines individual factors associated with the implementation, according to users' perspectives. A retrospective, cross-sectional survey was done between October 2010 and March 2011 in Kaduna state and 796 users were randomly interviewed. Questions regarding coverage of immediate-family members and access to benefit-package for treatment were analysed. Indicators of coverage and benefit-package access were each further aggregated and assessed by unit-weighted composite. The additive-ordinary least square regression model was used to identify user factors that may influence coverage and benefit-package access. With respect to coverage, immediate-dependants were included for 62.3% of the users, and 49.6 rated this inclusion 'good' (49.6%). In contrast, 60.2% supported the abolishment of the policy restriction for non-inclusion of enrolees' additional children and spouses. With respect to benefit-package access, 82.7% of users had received full treatments, and 77.6% of them rated this as 'good'. Also, 14.4% of users had been refused treatments because they could not afford them. The coverage of immediate-dependants was associated with age, sex, educational status, children and enrolment duration. The benefit-package access was associated with types of providers, marital status and duration of enrolment. This study revealed that coverage of family members was relatively poor, while benefit-package access was more adequate. Non-inclusion of family members could

  2. Effect of a Green Investment Society on the Dutch Renewable Energy Scheme (SDE); Effect Groene Investeringsmaatschappij op SDE

    Energy Technology Data Exchange (ETDEWEB)

    Lensink, S.M.; Van Stralen, J. [ECN Beleidsstudies, Petten (Netherlands)

    2012-11-27

    On request of the Holland Financial Centre, ECN has projected the potential benefits of a Green Investment Company for the expenditure of the SDE+ Scheme (Renewable Energy Incentivisation Scheme). To this end, a calculation was made of the effects of an interest rebate for sustainable energy projects [Dutch] Op verzoek van Holland Financial Centre heeft ECN geraamd wat de voordelen kunnen zijn van een Groene Investeringsmaatschappij op de uitgaven voor de SDE+ (Stimuleringsregeling Duurzame Energie). Hiertoe diende een berekening gemaakt te worden van de effecten van een rentekorting voor duurzame energieprojecten.

  3. A socio-economic assessment of proposed road user charging schemes in Copenhagen

    DEFF Research Database (Denmark)

    Rich, Jeppe; Nielsen, Otto Anker

    2007-01-01

    -economic analysis of four different proposed road pricing schemes for the Copenhagen area. The purpose was to assess all benefits and costs involved, including impacts on traffic and environment, maintenance and financing costs as well as tax distortion effects. It was concluded that the socio-economic surplus......Road pricing. congestion charging, toll-systems and other road charging instruments are intensively discussed in many countries. Although many partial analyses of the consequences have been published, few overall socio-economic analyses have been carried out. The article presents such a socio...... of the projects depends crucially on the congestion level. With the Current traffic level, road pricing will not yet be socially expedient in Copenhagen. However, if the opening year is postponed to 2015, the two most favourable schemes will turn positive. The analyses also showed that the magnitude of demand...

  4. Predictors of Availing Maternal Health Schemes: A community based study in Gujarat, India

    Directory of Open Access Journals (Sweden)

    Kranti Suresh Vora

    2014-06-01

    Full Text Available Background: India continues to face challenges in improving key maternal health indicators with about 1/3rd of global maternal deaths happening in India. Utilization of health care services is an important issue in India with significant proportion of home deliveries and majority of mothers not receiving adequate antenatal care. Mortality among poor rural women is the highest with lowest utilization. To make maternal healthcare more equitable, numerous schemes such as Janani Suraksha Yojana, Chiranjeevi Yojana, Kasturba Poshan Sahay Yojana have been introduced. Studies suggest that utilization of such schemes by target population is low and there is a need to understand factors affecting maternal health care utilization in the context of these schemes. Current community based study was done in rural Gujarat to understand characteristics of women who utilize such schemes and predictors of utilization. Methodology: Data collection was done in two districts of Gujarat from June to August, 2013 as a pilot phase of MATIND project. Community based cross-sectional study included 827 households and socio-demographic details of 1454 women of 15-49 years age groups were collected. 265 mothers, who had delivered after 1st January, 2013 are included in the regression analyses. The data analysis carried out with R version 3.0.1 software.  Results: The analysis indicates socioeconomic variables such as caste, maternal variables such as education and health system variables such as use of government facility are important predictors of maternal health scheme utilization. Results suggest that socioeconomic and health system factors are the best predictors for availing scheme. Conclusion: Health system variables along with individual level variables are important predictors for availing maternal health schemes. The study indicates the need to examine all levels of predictors for utilizing government health schemes to maximize the benefit for underserved

  5. RNAi-mediated silencing of MAP kinase signalling genes (Fmk1, Hog1, and Pbs2) in Fusarium oxysporum reduces pathogenesis on tomato plants.

    Science.gov (United States)

    Pareek, Manish; Rajam, Manchikatla Venkat

    2017-09-01

    Fusarium oxysporum is a soil-borne plant fungal pathogen, and causes colossal losses in several crop plants including tomato. Effective control measures include the use of harmful fungicides and resistant cultivars, but these methods have shown limited success. Conventional methods to validate fungal pathogenic genes are labour intensive. Therefore, an alternative strategy is required to efficiently characterize unknown pathogenic genes. RNA interference (RNAi) has emerged as a potential tool to functionally characterize novel fungal pathogenic genes and also to control fungal diseases. Here, we report an efficient method to produce stable RNAi transformants of F. oxysporum using Agrobacterium-mediated transformation (AMT). We have transformed F. oxysporum spores using RNAi constructs of Fmk1, Hog1, and Pbs2 MAP kinase signalling genes. Fmk1 RNAi fungal transformants showed loss of surface hydrophobicity, reduced invasive growth on tomato fruits and hypo-virulence on tomato seedlings. Hog1 and Pbs2 RNAi transformants showed altered conidial size, and reduced invasive growth and pathogenesis. These results showed that AMT using RNAi constructs is an effective approach for dissecting the role of genes involved in pathogenesis in F. oxysporum and this could be extended for other fungal systems. The obtained knowledge can be easily translated for developing fungal resistant crops by RNAi. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  6. Scheme Program Documentation Tools

    DEFF Research Database (Denmark)

    Nørmark, Kurt

    2004-01-01

    are separate and intended for different documentation purposes they are related to each other in several ways. Both tools are based on XML languages for tool setup and for documentation authoring. In addition, both tools rely on the LAML framework which---in a systematic way---makes an XML language available...... as named functions in Scheme. Finally, the Scheme Elucidator is able to integrate SchemeDoc resources as part of an internal documentation resource....

  7. Oscillator strength and quantum-confined Stark effect of excitons in a thin PbS quantum disk

    Science.gov (United States)

    Oukerroum, A.; El-Yadri, M.; El Aouami, A.; Feddi, E.; Dujardin, F.; Duque, C. A.; Sadoqi, M.; Long, G.

    2018-01-01

    In this paper, we report a study of the effect of a lateral electric field on a quantum-confined exciton in a thin PbS quantum disk. Our approach was performed in the framework of the effective mass theory and adiabatic approximation. The ground state energy and the stark shift were determined by using a variational method with an adequate trial wavefunction, by investigating a 2D oscillator strength under simultaneous consideration of the geometrical confinement and the electric field strength. Our results showed a strong dependence of the exciton binding and the Stark shift on the disk dimensions in both axial and longitudinal directions. On the other hand, our results also showed that the Stark shift’s dependence on the electric field is not purely quadratic but the linear contribution is also important and cannot be neglected, especially when the confinement gets weaker.

  8. A Memory Efficient Network Encryption Scheme

    Science.gov (United States)

    El-Fotouh, Mohamed Abo; Diepold, Klaus

    In this paper, we studied the two widely used encryption schemes in network applications. Shortcomings have been found in both schemes, as these schemes consume either more memory to gain high throughput or low memory with low throughput. The need has aroused for a scheme that has low memory requirements and in the same time possesses high speed, as the number of the internet users increases each day. We used the SSM model [1], to construct an encryption scheme based on the AES. The proposed scheme possesses high throughput together with low memory requirements.

  9. Modified Aggressive Packet Combining Scheme

    International Nuclear Information System (INIS)

    Bhunia, C.T.

    2010-06-01

    In this letter, a few schemes are presented to improve the performance of aggressive packet combining scheme (APC). To combat error in computer/data communication networks, ARQ (Automatic Repeat Request) techniques are used. Several modifications to improve the performance of ARQ are suggested by recent research and are found in literature. The important modifications are majority packet combining scheme (MjPC proposed by Wicker), packet combining scheme (PC proposed by Chakraborty), modified packet combining scheme (MPC proposed by Bhunia), and packet reversed packet combining (PRPC proposed by Bhunia) scheme. These modifications are appropriate for improving throughput of conventional ARQ protocols. Leung proposed an idea of APC for error control in wireless networks with the basic objective of error control in uplink wireless data network. We suggest a few modifications of APC to improve its performance in terms of higher throughput, lower delay and higher error correction capability. (author)

  10. What are key determinants of hospital admissions, readmission rate and day case rate within the South African medical schemes population?

    Directory of Open Access Journals (Sweden)

    Nondumiso Gugu Khumalo

    2012-06-01

    Full Text Available  BACKGROUND: In South Africa, private hospitals absorb a high proportion of the total health expenditure on private health care. Between 2008-2010 private hospital expenditure which includes ward fees, theatre fees, consumables, medicines and per diem arrangements consumed between 40.5% and 40.9% of the total benefits paid by medical schemes from the risk pool, whilst in-hospital managed care fees ranged between 1.8% and 2.8% for the equivalent years.OBJECTIVE: The aim of this paper is to highlight key factors contributing to utilisation of hospital services within the medical schemes population and to recommend “appropriate” and cost effective strategies on hospital utilisation management.METHODS: A cross sectional survey informed by retrospective analysis of quantitative data was used. Researchers also triangulated quantitative data with systematic review of literature.RESULTS: The results show that demographic indicators such as age profile, dependency ratio, pensioner ratio and prevalence of chronic conditions are not the only key factors influencing hospital admissions, but rather the effectiveness of each medical scheme in containing hospital admissions is also influenced by available technical capacity on utilisation review and audit as well as the managed care methodology including the philosophy underpinning benefit option design.CONCLUSION: This study highlights the importance of “value based” managed care programs linked to benefit option design in health care utilisation management. The choice of one managed care program over the other often leads to tradeoffs whereby unintended consequences emanate. Medical schemes are therefore encouraged to continuously review their managed care programs to ensure value for money as well as better access and health outcomes.http://dx.doi.org/10.7175/fe.v13i2.207

  11. How Well-Informed Are Pension Scheme Members on Their Future Pension Benefits? Evidence from Ireland.

    Science.gov (United States)

    Barrett, Alan; Mosca, Irene; Whelan, Brendan

    2015-01-01

    One part of the policy response in many countries to increasing pension coverage will be greater private provision on the part of individuals. This requires that individuals are well informed about pensions. In this article, we assess levels of knowledge of pensions using a representative sample of older Irish adults. We find that two-thirds of individuals enrolled in pension schemes do not know what amount will be paid out on retirement and/or whether the payments will be in the form of lump sums, monthly payments, or both. One policy implication is the need for increased information to be directed at certain groups, in particular, women and less educated people. More fundamentally, the results suggest that the mandatory elements in pension systems should be extended.

  12. A secure data outsourcing scheme based on Asmuth-Bloom secret sharing

    Science.gov (United States)

    Idris Muhammad, Yusuf; Kaiiali, Mustafa; Habbal, Adib; Wazan, A. S.; Sani Ilyasu, Auwal

    2016-11-01

    Data outsourcing is an emerging paradigm for data management in which a database is provided as a service by third-party service providers. One of the major benefits of offering database as a service is to provide organisations, which are unable to purchase expensive hardware and software to host their databases, with efficient data storage accessible online at a cheap rate. Despite that, several issues of data confidentiality, integrity, availability and efficient indexing of users' queries at the server side have to be addressed in the data outsourcing paradigm. Service providers have to guarantee that their clients' data are secured against internal (insider) and external attacks. This paper briefly analyses the existing indexing schemes in data outsourcing and highlights their advantages and disadvantages. Then, this paper proposes a secure data outsourcing scheme based on Asmuth-Bloom secret sharing which tries to address the issues in data outsourcing such as data confidentiality, availability and order preservation for efficient indexing.

  13. Survey on Industry Requirements and Drivers for the Development of a Process-Related Certification Scheme for Ecodesign Implementation and Management

    DEFF Research Database (Denmark)

    Pigosso, Daniela Cristina Antelmi; Jakobsen, Maja; McAloone, Tim C.

    2014-01-01

    Despite the existence of a large amount of eco-labels and eco-standards for product declaration, there is still limited research for the development of process-related certification schemes dealing with ecodesign implementation and management. In order to identify companies’ drivers, barriers...... and expected benefits in regards to the development and application of process-related ecodesign certification schemes, a survey was carried out inthis research. This paper presents and discusses the main results obtained in the survey, which comprised the participation of more than 100 professionals from more...... than 25 countries. The results will be employed for the development of an ecodesign process-related certification scheme based on the Ecodesign Maturity Model (EcoM2)....

  14. Forging alliance with Russia. The example of a Green Investment Scheme

    International Nuclear Information System (INIS)

    Korppoo, Anna

    2003-01-01

    Russian Kyoto related interests are economic and after the US withdrawal the mission of Russian actors has been to find new demand for Russian credits and allowances. Kyoto related benefits to Russia will be significantly smaller than earlier expected, however, the revenues are now more likely to be focused on climate change mitigation purposes. Competition in the Kyoto market has established buyers' market and Russia has to accommodate the interests of investors in order to gain benefits. The Russian initiative 'Green Investment Scheme' to recycle revenues from International Emissions Trading (IET) to further environmental activities would convene demand for Russian AAUs but experience the same problems than the previous initiatives: inadequate institutional arrangement, unclear division of responsibilities between domestic actors, prolonged ratification process and lack of eligibility strategy. These problems have prevented implementation of GIS so far. Therefore, these problems have to be addressed by high-level Russian policy-makers if serious benefits from Kyoto are sought. Actors building alliances with Russia should focus on assisting with solving these problems

  15. Passive mode locking of 2.09 microm Cr,Tm,Ho:Y3Sc2Al3O12 laser using PbS quantum-dot-doped glass.

    Science.gov (United States)

    Denisov, Igor A; Skoptsov, Nikolai A; Gaponenko, Maxim S; Malyarevich, Alexander M; Yumashev, Konstantin V; Lipovskii, Andrei A

    2009-11-01

    Passive Q-switched mode locking of a 2.09 microm flashlamp-pumped Cr(3+),Tm(3+),Ho(3+):Y(3)Sc(2)Al(3)O(12) laser by use of a phosphate glass doped with PbS quantum dots of 5 nm in radius was demonstrated. Mode-locked pulses of 290 ps in duration and up to 0.5 mJ in energy were registered.

  16. Water-mediated green synthesis of PbS quantum dot and its glutathione and biotin conjugates for non-invasive live cell imaging

    Science.gov (United States)

    Vijaya Bharathi, M.; Maiti, Santanu; Sarkar, Bidisha; Ghosh, Kaustab; Paira, Priyankar

    2018-03-01

    This study addresses the cellular uptake of nanomaterials in the field of bio-applications. In the present study, we have synthesized water-soluble lead sulfide quantum dot (PbS QD) with glutathione and 3-MPA (mercaptopropionic acid) as the stabilizing ligand using a green approach. 3-MPA-capped QDs were further modified with streptavidin and then bound to biotin because of its high conjugation efficiency. Labelling and bio-imaging of cells with these bio-conjugated QDs were evaluated. The bright red fluorescence from these types of QDs in HeLa cells makes these materials suitable for deep tissue imaging.

  17. Bonus schemes and trading activity

    NARCIS (Netherlands)

    Pikulina, E.S.; Renneboog, L.D.R.; ter Horst, J.R.; Tobler, P.N.

    2014-01-01

    Little is known about how different bonus schemes affect traders' propensity to trade and which bonus schemes improve traders' performance. We study the effects of linear versus threshold bonus schemes on traders' behavior. Traders buy and sell shares in an experimental stock market on the basis of

  18. Constant envelope OFDM scheme for 6PolSK-QPSK

    Science.gov (United States)

    Li, Yupeng; Ding, Ding

    2018-03-01

    A constant envelope OFDM scheme with phase modulator (PM-CE-OFDM) for 6PolSK-QPSK modulation was demonstrated. Performance under large fiber launch power is measured to check its advantages in counteracting fiber nonlinear impairments. In our simulation, PM-CE-OFDM, RF-assisted constant envelope OFDM (RF-CE-OFDM) and conventional OFDM (Con-OFDM) are transmitted through 80 km standard single mode fiber (SSMF) single channel and WDM system. Simulation results confirm that PM-CE-OFDM has best performance in resisting fiber nonlinearity. In addition, benefiting from the simple system structure, the complexity and cost of PM-CE-OFDM system could be reduced effectively.

  19. Batching System for Superior Service

    Science.gov (United States)

    2001-01-01

    Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.

  20. The fabrication and analysis of a PbS nanocrystal:C{sub 60} bilayer hybrid photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Dissanayake, D M N M [Solid State Electronics Laboratory, University of Michigan, Ann Arbor, MI 48109-2122 (United States); Hatton, R A [Department of Chemistry, University of Warwick, Coventry CV4 7AL (United Kingdom); Lutz, T [Department of Chemistry, Imperial College, London SW7 2AY (United Kingdom); Curry, R J; Silva, S R P [Advanced Technology Institute, University of Surrey, Guildford GU2 7XH (United Kingdom)], E-mail: ndissa@umich.edu

    2009-06-17

    A near-infrared sensitive hybrid photovoltaic system between PbS nanocrystals (PbS-NCs) and C{sub 60} is demonstrated. Up to 0.44% power conversion efficiency is obtained under AM1.5G with a short circuit current density (J{sub sc}) of 5 mA cm{sup -2} when the PbS-NC layer is treated in anhydrous methanol. The observed J{sub sc} is found be approximately one-third of the maximum expected from this hybrid configuration, indicating the potential for further optimization. Crucial for device operation, a smooth film of nanocrystals is seen to form on the hole transporting poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) layer deposited on the transparent electrode, facilitated through an ionic interaction between nanocrystal capping ligands and the PEDOT:PSS. The formation of the open circuit voltage in this system is seen to be influenced by an interfacial dipole formed at the hole-extracting electrode, providing insights for further optimization.

  1. Aging effect of quantum dots on solar cells sensitized with nano-crystals of CdS and PbS

    Directory of Open Access Journals (Sweden)

    V Borhanifar

    2015-01-01

    Full Text Available In this research, solar cells sensitized with CdS and PbS Nanocrystalline metal sulfides, chemically grown by SILAR, were fabricated and characterized. PV experiments including I-V test in the presence of light and dark,Vocdecay, and Electrochemical impedance spectroscopy were performed on the Cells made through this method in the presence of light and dark and in the time period of 2, 3, 6 and 10 days. From these experiments, the changes in indicators including fill factor, efficiency, open-circuit voltage, short-circuit current, lifetime of electrons in nanostructured anode electrode, recombination resistance and capacitance of the anode electrode-electrolyte interface were observed. Also, mechanisms for some existing evidences within photovoltaic experiments such as the increase and decrease of recombination resistance were proposed.

  2. CSR schemes in agribusiness

    DEFF Research Database (Denmark)

    Pötz, Katharina Anna; Haas, Rainer; Balzarova, Michaela

    2013-01-01

    of schemes that can be categorized on focus areas, scales, mechanisms, origins, types and commitment levels. Research limitations/implications – The findings contribute to conceptual and empirical research on existing models to compare and analyse CSR standards. Sampling technique and depth of analysis limit......Purpose – The rise of CSR followed a demand for CSR standards and guidelines. In a sector already characterized by a large number of standards, the authors seek to ask what CSR schemes apply to agribusiness, and how they can be systematically compared and analysed. Design....../methodology/approach – Following a deductive-inductive approach the authors develop a model to compare and analyse CSR schemes based on existing studies and on coding qualitative data on 216 CSR schemes. Findings – The authors confirm that CSR standards and guidelines have entered agribusiness and identify a complex landscape...

  3. Optimization of Compton-suppression and summing schemes for the TIGRESS HPGe detector array

    Science.gov (United States)

    Schumaker, M. A.; Svensson, C. E.; Andreoiu, C.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Boston, A. J.; Chakrawarthy, R. S.; Churchman, R.; Drake, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hackman, G.; Hyland, B.; Jones, B.; Maharaj, R.; Morton, A. C.; Pearson, C. J.; Phillips, A. A.; Sarazin, F.; Scraggs, H. C.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Watters, L. M.

    2007-04-01

    Methods of optimizing the performance of an array of Compton-suppressed, segmented HPGe clover detectors have been developed which rely on the physical position sensitivity of both the HPGe crystals and the Compton-suppression shields. These relatively simple analysis procedures promise to improve the precision of experiments with the TRIUMF-ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS). Suppression schemes will improve the efficiency and peak-to-total ratio of TIGRESS for high γ-ray multiplicity events by taking advantage of the 20-fold segmentation of the Compton-suppression shields, while the use of different summing schemes will improve results for a wide range of experimental conditions. The benefits of these methods are compared for many γ-ray energies and multiplicities using a GEANT4 simulation, and the optimal physical configuration of the TIGRESS array under each set of conditions is determined.

  4. Threshold Signature Schemes Application

    Directory of Open Access Journals (Sweden)

    Anastasiya Victorovna Beresneva

    2015-10-01

    Full Text Available This work is devoted to an investigation of threshold signature schemes. The systematization of the threshold signature schemes was done, cryptographic constructions based on interpolation Lagrange polynomial, elliptic curves and bilinear pairings were examined. Different methods of generation and verification of threshold signatures were explored, the availability of practical usage of threshold schemes in mobile agents, Internet banking and e-currency was shown. The topics of further investigation were given and it could reduce a level of counterfeit electronic documents signed by a group of users.

  5. A Spatial Domain Quantum Watermarking Scheme

    International Nuclear Information System (INIS)

    Wei Zhan-Hong; Chen Xiu-Bo; Niu Xin-Xin; Yang Yi-Xian; Xu Shu-Jiang

    2016-01-01

    This paper presents a spatial domain quantum watermarking scheme. For a quantum watermarking scheme, a feasible quantum circuit is a key to achieve it. This paper gives a feasible quantum circuit for the presented scheme. In order to give the quantum circuit, a new quantum multi-control rotation gate, which can be achieved with quantum basic gates, is designed. With this quantum circuit, our scheme can arbitrarily control the embedding position of watermark images on carrier images with the aid of auxiliary qubits. Besides reversely acting the given quantum circuit, the paper gives another watermark extracting algorithm based on quantum measurements. Moreover, this paper also gives a new quantum image scrambling method and its quantum circuit. Differ from other quantum watermarking schemes, all given quantum circuits can be implemented with basic quantum gates. Moreover, the scheme is a spatial domain watermarking scheme, and is not based on any transform algorithm on quantum images. Meanwhile, it can make sure the watermark be secure even though the watermark has been found. With the given quantum circuit, this paper implements simulation experiments for the presented scheme. The experimental result shows that the scheme does well in the visual quality and the embedding capacity. (paper)

  6. Urinary Escherichia coli antimicrobial susceptibility profiles and their relationship with community antibiotic use in Tasmania, Australia.

    Science.gov (United States)

    Meumann, Ella M; Mitchell, Brett G; McGregor, Alistair; McBryde, Emma; Cooley, Louise

    2015-10-01

    This study assessed urinary Escherichia coli antibiotic susceptibility patterns in Tasmania, Australia, and examined their association with community antibiotic use. The susceptibility profiles of all urinary E. coli isolates collected in Tasmania between January 2010 and December 2012 were included. The amount of Pharmaceutical Benefits Scheme (PBS)-subsidised use of amoxicillin, amoxicillin/clavulanic acid (AMC), cefalexin, norfloxacin, ciprofloxacin and trimethoprim was retrieved (at the Tasmanian population level) and the number of defined daily doses per 1000 population per day in Tasmania for these antibiotics was calculated for each month during the study period. Antimicrobial susceptibility data were assessed for changes over time in the 3-year study period. Antimicrobial use and susceptibility data were assessed for seasonal differences and lag in resistance following antibiotic use. Excluding duplicates, 28145 E. coli isolates were included. Resistance levels were low; 35% of isolates were non-susceptible to amoxicillin, 14% were non-susceptible to trimethoprim and antibiotics for treatment of respiratory tract infections in winter. Quinolone use is restricted by the PBS in Australia, which is the likely explanation for the low levels of quinolone use and resistance identified. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  7. Labeling schemes for bounded degree graphs

    DEFF Research Database (Denmark)

    Adjiashvili, David; Rotbart, Noy Galil

    2014-01-01

    We investigate adjacency labeling schemes for graphs of bounded degree Δ = O(1). In particular, we present an optimal (up to an additive constant) log n + O(1) adjacency labeling scheme for bounded degree trees. The latter scheme is derived from a labeling scheme for bounded degree outerplanar...... graphs. Our results complement a similar bound recently obtained for bounded depth trees [Fraigniaud and Korman, SODA 2010], and may provide new insights for closing the long standing gap for adjacency in trees [Alstrup and Rauhe, FOCS 2002]. We also provide improved labeling schemes for bounded degree...

  8. Markets for energy efficiency: Exploring the implications of an EU-wide 'Tradable White Certificate' scheme

    International Nuclear Information System (INIS)

    Mundaca, Luis

    2008-01-01

    Recent developments in European energy policy reveal an increasing interest in implementing the so-called 'Tradable White Certificate' (TWC) schemes to improve energy efficiency. Based on three evaluation criteria (cost-effectiveness, environmental effectiveness and distributional equity) this paper analyses the implications of implementing a European-wide TWC scheme targeting the household and commercial sectors. Using a bottom-up model, quantitative results show significant cost-effective potentials for improvements (ca. 1400 TWh in cumulative energy savings by 2020), with the household sector, gas and space heating representing most of the TWC supply in terms of eligible sector, fuel and energy service demand, respectively. If a single market price of negative externalities is considered, a societal cost-effective potential of energy savings above 30% (compared to the baseline) is observed. In environmental terms, the resulting greenhouse gas emission reductions are around 200 Mt CO 2-eq by 2010, representing nearly 60% of the EU-Kyoto-target. From the qualitative perspective, several embedded ancillary benefits are identified (e.g. employment generation, improved comfort level, reduced 'fuel poverty', security of energy supply). Whereas an EU-wide TWC increases liquidity and reduces the risks of market power, autarky compliance strategies may be expected in order to capture co-benefits nationally. Cross subsidies could occur due to investment recovery mechanisms and there is a risk that effects may be regressive for low-income households. Assumptions undertaken by the modelling approach strongly indicate that high effectiveness of other policy instruments is needed for an EU-wide TWC scheme to be cost-effective

  9. Is it worth protecting groundwater from diffuse pollution with agri-environmental schemes? A hydro-economic modeling approach.

    Science.gov (United States)

    Hérivaux, Cécile; Orban, Philippe; Brouyère, Serge

    2013-10-15

    In Europe, 30% of groundwater bodies are considered to be at risk of not achieving the Water Framework Directive (WFD) 'good status' objective by 2015, and 45% are in doubt of doing so. Diffuse agricultural pollution is one of the main pressures affecting groundwater bodies. To tackle this problem, the WFD requires Member States to design and implement cost-effective programs of measures to achieve the 'good status' objective by 2027 at the latest. Hitherto, action plans have mainly consisted of promoting the adoption of Agri-Environmental Schemes (AES). This raises a number of questions concerning the effectiveness of such schemes for improving groundwater status, and the economic implications of their implementation. We propose a hydro-economic model that combines a hydrogeological model to simulate groundwater quality evolution with agronomic and economic components to assess the expected costs, effectiveness, and benefits of AES implementation. This hydro-economic model can be used to identify cost-effective AES combinations at groundwater-body scale and to show the benefits to be expected from the resulting improvement in groundwater quality. The model is applied here to a rural area encompassing the Hesbaye aquifer, a large chalk aquifer which supplies about 230,000 inhabitants in the city of Liege (Belgium) and is severely contaminated by agricultural nitrates. We show that the time frame within which improvements in the Hesbaye groundwater quality can be expected may be much longer than that required by the WFD. Current WFD programs based on AES may be inappropriate for achieving the 'good status' objective in the most productive agricultural areas, in particular because these schemes are insufficiently attractive. Achieving 'good status' by 2027 would demand a substantial change in the design of AES, involving costs that may not be offset by benefits in the case of chalk aquifers with long renewal times. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Multiresolution signal decomposition schemes

    NARCIS (Netherlands)

    J. Goutsias (John); H.J.A.M. Heijmans (Henk)

    1998-01-01

    textabstract[PNA-R9810] Interest in multiresolution techniques for signal processing and analysis is increasing steadily. An important instance of such a technique is the so-called pyramid decomposition scheme. This report proposes a general axiomatic pyramid decomposition scheme for signal analysis

  11. Psychosocial routes from housing investment to health: Evidence from England's home energy efficiency scheme

    International Nuclear Information System (INIS)

    Gilbertson, Jan; Grimsley, Michael; Green, Geoff

    2012-01-01

    Over the past decade the Warm Front Scheme has been the English Government's principal programme for improving domestic energy efficiency and reducing fuel poverty. This paper reports on a cross-sectional survey of low income householders participating in the Warm Front Scheme in five urban areas of England. Surveys were conducted of 2685 individuals, before and or after intervention. Pathways to self reported health were modelled by logistic regression. Of all the dimensions of health examined, only self reported mental health is directly associated with Warm Front measures. Intermediary variables associated with Warm Front intervention were shown to be significantly correlated with more dimensions of self reported health status. Higher temperatures, satisfaction with the heating system, greater thermal comfort, reductions in fuel poverty and lower stress were significantly correlated with improved health. Alleviating fuel poverty and reducing stress appeared to be the main route to health. We conclude there are complex and indirect relationships linking energy efficiency measures to outcomes on all dimensions of health which contribute to significant material and psychosocial benefits. The impact of the Warm Front Scheme cannot be fully understood by a limited analysis which merely relates indoor temperature and property characteristics to physiological health outcomes. - Highlights: ► Warm Front improvements are linked to significant material and psychosocial benefits. ► The alleviation of fuel poverty and the reduction of stress emerge as the likely route to health. ► The scope for improving health is greater than implied by the UK Government's Fuel Poverty Strategy. ► A dual but integrated approach to alleviating cold living conditions and fuel poverty is required.

  12. Bicycle and Car Share Schemes as Inclusive Modes of Travel? A Socio-Spatial Analysis in Glasgow, UK

    Directory of Open Access Journals (Sweden)

    Julie Clark

    2016-06-01

    Full Text Available Public bicycle and car sharing schemes have proliferated in recent years and are increasingly part of the urban transport landscape. Shared transport options have the potential to support social inclusion by improving accessibility: these initiatives could remove some of the barriers to car ownership or bicycle usage such as upfront costs, maintenance and storage. However, the existing evidence base indicates that, in reality, users are most likely to be white, male and middle class. This paper argues that there is a need to consider the social inclusivity of sharing schemes and to develop appropriate evaluation frameworks accordingly. We therefore open by considering ways in which shared transport schemes might be inclusive or not, using a framework developed from accessibility planning. In the second part of the paper, we use the case study of Glasgow in Scotland to undertake a spatial equity analysis of such schemes. We examine how well they serve different population groups across the city, using the locations of bicycle stations and car club parking spaces in Glasgow, comparing and contrasting bike and car. An apparent failure to deliver benefits across the demographic spectrum raises important questions about the socially inclusive nature of public investment in similar schemes.

  13. Tabled Execution in Scheme

    Energy Technology Data Exchange (ETDEWEB)

    Willcock, J J; Lumsdaine, A; Quinlan, D J

    2008-08-19

    Tabled execution is a generalization of memorization developed by the logic programming community. It not only saves results from tabled predicates, but also stores the set of currently active calls to them; tabled execution can thus provide meaningful semantics for programs that seemingly contain infinite recursions with the same arguments. In logic programming, tabled execution is used for many purposes, both for improving the efficiency of programs, and making tasks simpler and more direct to express than with normal logic programs. However, tabled execution is only infrequently applied in mainstream functional languages such as Scheme. We demonstrate an elegant implementation of tabled execution in Scheme, using a mix of continuation-passing style and mutable data. We also show the use of tabled execution in Scheme for a problem in formal language and automata theory, demonstrating that tabled execution can be a valuable tool for Scheme users.

  14. Optimal Face-Iris Multimodal Fusion Scheme

    Directory of Open Access Journals (Sweden)

    Omid Sharifi

    2016-06-01

    Full Text Available Multimodal biometric systems are considered a way to minimize the limitations raised by single traits. This paper proposes new schemes based on score level, feature level and decision level fusion to efficiently fuse face and iris modalities. Log-Gabor transformation is applied as the feature extraction method on face and iris modalities. At each level of fusion, different schemes are proposed to improve the recognition performance and, finally, a combination of schemes at different fusion levels constructs an optimized and robust scheme. In this study, CASIA Iris Distance database is used to examine the robustness of all unimodal and multimodal schemes. In addition, Backtracking Search Algorithm (BSA, a novel population-based iterative evolutionary algorithm, is applied to improve the recognition accuracy of schemes by reducing the number of features and selecting the optimized weights for feature level and score level fusion, respectively. Experimental results on verification rates demonstrate a significant improvement of proposed fusion schemes over unimodal and multimodal fusion methods.

  15. Coordination Scheme for Restructuring Business Operation of the Single Period Newsvendor Problem

    Directory of Open Access Journals (Sweden)

    Chiuh-Cheng Chyu

    2013-01-01

    Full Text Available This paper presents a coordination scheme for a single period newsvendor problem when both supplier and retailer of the supply chain agree to change the business operation from a market decision power sharing system (Model 1 to a unique decision maker system (Model 2. The supplier is assumed to be a risk-averse decision maker and he will undertake the product quality risk in both models. Model 1 is game theoretic, where the supplier controls the wholesale price, but the retailer controls the order quantity and market price. The bargaining process ends when the supplier has found a wholesale price that maximizes the value of his sales revenue minus the product quality cost. Model 2 is a centralized system where the supplier possesses all decision powers of the market. In general, Model 2 will generate higher total revenue than Model 1. The aim of this research is to propose a satisfying compromise based on consignment policy to resolve the revenue-sharing conflict in Model 2 due to the additional revenue. An example is provided to illustrate the two models and the proposed coordination scheme, along with managerial insights on the models’ benefits. The impacts of several parameters on the scheme are also presented and discussed.

  16. Public Private Partnership Benefits in Delivering Public Facilities in Malaysia

    Directory of Open Access Journals (Sweden)

    Sapri M.

    2016-01-01

    Full Text Available The development of infrastructure in developing country such as Malaysia was increasingly founded by the Public–Private Partnership (PPP scheme. Collaboration with private sector has become popular as a means to improve the delivery of public facilities. Yet, empirical evidence on how PPP initiative has benefits the delivery of public facilities within Malaysia context is lagging. The purpose of this paper is to identify and assess the perception of stakeholders on the benefits of adopting PPP in delivering public facilities in Malaysia. Literature review was carried out to identify PPP benefits, which were then incorporated into the questionnaire. The mean score and mean score ranking was conducted to assess the agreement level of stakeholders towards the PPP benefits. The overall findings show that the implementation of PPP has benefitted the delivery of public facilities in both financial and non-financial aspects. From the analysis, improvement in service quality is perceived as the top advantage followed by innovation in design and transfer of risk. The findings provide more informed basis on the rationale of PPP implementation and its potential in improving the delivery of public facilities within Malaysia context.

  17. A MEPS is a MEPS is a MEPS. Comparing Ecodesign and Top Runner schemes for setting product efficiency standards

    Energy Technology Data Exchange (ETDEWEB)

    Siderius, P.J.S. [NL Agency, Croeselaan 15, P.O. Box 8242, 3503 RE Utrecht (Netherlands); Nakagami, H. [Jyukankyo Research Institute, 3-29, Kioi-cho, Chiyoda-ku Tokyo, 102-0094 (Japan)

    2013-02-15

    Both Top Runner in Japan and Ecodesign in the European Union are schemes to set requirements on the energy efficiency (minimum efficiency performance standards, MEPS) of a variety of products. This article provides an overview of the main characteristics and results of both schemes and gives recommendations for improving them. Both schemes contribute significantly to the energy efficiency targets set by the European Commission and the Japanese government. Although it is difficult to compare the absolute levels of the requirements, comparison of the relative improvements and of the savings on household electricity consumption (11 % in Japan, 16 % in the EU) suggest they are in the same range. Furthermore, the time needed to set or review requirements is in both schemes considerable (between 5 and 6 years on average) and the manageability increasingly will become a challenge. The appeal of the Top Runner approach is that the most efficient product (Top Runner) sets the standard for all products at the next target year. Although the Ecodesign scheme includes the elements for a Top Runner approach, it could exploit this principle more explicitly. On the other hand, the Top Runner scheme could benefit by using a real minimum efficiency performance standard instead of a fleet average. This would make the monitoring and enforcement more simple and transparent, and would open the scheme for products where the market situation is less clear.

  18. A new water treatment scheme for thermal development : the SIBE process

    Energy Technology Data Exchange (ETDEWEB)

    Pedenaud, P.; Dang, F. [Total, Paris (France)

    2008-10-15

    The production of extra heavy oil or bitumen through thermal methods such as steam assisted gravity drainage (SAGD) involves the generation and injection into the reservoir of large quantities of steam which is recirculated with the produced bitumen. It is expected that maximizing the recycling of the produced water into steam will be mandatory, because of the need to minimize fresh water consumption and the possibility of increasingly stringent environmental regulations. The SAGD water treatment scheme is complex. It depends on the water characteristics, the steam generator type selected, and the decision to completely eliminate waste water disposal or use other waste handling and disposal methods. Other challenges such as the high silica content in the produced water, are encountered with SAGD water treatment. This paper presented an overview of the current water treatment process options for SAGD, as well as a new patented process called silica inhibition and blowdown evaporation (SIBE). The paper also presented an estimate of the economic benefit of the new SIBE process relative to conventional process schemes. Treatment objectives and water characteristics and the steps involved in conventional water treatment were first outlined. It was concluded that the silica and hardness removal scheme combined with the boiler blowdown evaporator were less economical because of higher investment cost due to the evaporation unit. 1 ref., 3 tabs., 4 figs.

  19. Poverty and Christian Welfare Scheme: Evidence from the Church of Nigeria (Anglican Communion Osun State, Nigeria

    Directory of Open Access Journals (Sweden)

    S. Awoniyi

    2015-05-01

    Full Text Available Existing studies on welfare schemes in Nigerian Churches have focussed on the political and economic perspectives, neglecting the ethical dimension which has a stronger basis in the Bible. This study, therefore, examined the welfare scheme of the Church of Nigeria (Anglican Communion, Osun State, Nigeria as evidence with a view to assessing their method of generating welfare resources, as well as their implementation and monitoring strategy against the provision of the Bible on welfare ethics. Data were obtained through interviews, observation and questionnaire. In-depth interviews were conducted with 90 randomly selected key informants including 12 clergy, 24 poor members of the church, 18 welfare scheme officers and 36 beneficiaries. Four welfare schemes were observed between 1991 -2012 in a total of 30 Anglican Churches in major towns in Osun State. A total of 600 copies of the questionnaire were purposively administered to beneficiaries, church members and welfare scheme officers. Out of these, 550 were retrieved and analysed using percentages. The Church of Nigeria (Anglican Communion generated resources for welfare schemes through compulsory  levies, donations, annual harvest proceeds, offering collection ,tithes/offering and foreign assistance .Four categories of welfare schemes were adopted: Health care delivery, vocational rehabilitation, micro-credit loans, and women’s empowerment. One implementation strategy was adopted, namely, social advocacy. The church utilized sensitisation mechanism, widow retreat workshops, free health campaign, radio/television programmes and supportive counselling. Welfare scheme for the Church of Nigeria offered socio-economic benefits to members of the Church, but they were weakened by limited human coverage, insufficient funds and poor monitoring. These call for moral reorientation on the part of stakeholders in order to inculcate the ethics of justice and fairness as enshrined in the Bible.

  20. REMINDER Saved Leave Scheme (SLS) : Transfer of leave to saved leave accounts

    CERN Multimedia

    HR Division

    2002-01-01

    Under the provisions of the voluntary saved leave scheme (SLS), a maximum total of 10 days'*) annual and compensatory leave (excluding saved leave accumulated in accordance with the provisions of Administrative Circular No. 22B) can be transferred to the saved leave account at the end of the leave year (30 September). We remind you that, since last year, unused leave of all those taking part in the saved leave scheme at the closure of the leave-year accounts is transferred automatically to the saved leave account on that date. Therefore, staff members have no administrative steps to take. In addition, the transfer, which eliminates the risk of omitting to request leave transfers and rules out calculation errors in transfer requests, will be clearly shown in the list of leave transactions that can be consulted in EDH from October 2002 onwards. Furthermore, this automatic leave transfer optimizes staff members' chances of benefiting from a saved leave bonus provided that they are still participants in the schem...

  1. Optimization of refueling-shuffling scheme in PWR core by random search strategy

    International Nuclear Information System (INIS)

    Wu Yuan

    1991-11-01

    A random method for simulating optimization of refueling management in a pressurized water reactor (PWR) core is described. The main purpose of the optimization was to select the 'best' refueling arrangement scheme which would produce maximum economic benefits under certain imposed conditions. To fulfill this goal, an effective optimization strategy, two-stage random search method was developed. First, the search was made in a manner similar to the stratified sampling technique. A local optimum can be reached by comparison of the successive results. Then the other random experiences would be carried on between different strata to try to find the global optimum. In general, it can be used as a practical tool for conventional fuel management scheme. However, it can also be used in studies on optimization of Low-Leakage fuel management. Some calculations were done for a typical PWR core on a CYBER-180/830 computer. The results show that the method proposed can obtain satisfactory approach at reasonable low computational cost

  2. Exploring a new quantitative image marker to assess benefit of chemotherapy to ovarian cancer patients

    Science.gov (United States)

    Mirniaharikandehei, Seyedehnafiseh; Patil, Omkar; Aghaei, Faranak; Wang, Yunzhi; Zheng, Bin

    2017-03-01

    Accurately assessing the potential benefit of chemotherapy to cancer patients is an important prerequisite to developing precision medicine in cancer treatment. The previous study has shown that total psoas area (TPA) measured on preoperative cross-section CT image might be a good image marker to predict long-term outcome of pancreatic cancer patients after surgery. However, accurate and automated segmentation of TPA from the CT image is difficult due to the fuzzy boundary or connection of TPA to other muscle areas. In this study, we developed a new interactive computer-aided detection (ICAD) scheme aiming to segment TPA from the abdominal CT images more accurately and assess the feasibility of using this new quantitative image marker to predict the benefit of ovarian cancer patients receiving Bevacizumab-based chemotherapy. ICAD scheme was applied to identify a CT image slice of interest, which is located at the level of L3 (vertebral spines). The cross-sections of the right and left TPA are segmented using a set of adaptively adjusted boundary conditions. TPA is then quantitatively measured. In addition, recent studies have investigated that muscle radiation attenuation which reflects fat deposition in the tissue might be a good image feature for predicting the survival rate of cancer patients. The scheme and TPA measurement task were applied to a large national clinical trial database involving 1,247 ovarian cancer patients. By comparing with manual segmentation results, we found that ICAD scheme could yield higher accuracy and consistency for this task. Using a new ICAD scheme can provide clinical researchers a useful tool to more efficiently and accurately extract TPA as well as muscle radiation attenuation as new image makers, and allow them to investigate the discriminatory power of it to predict progression-free survival and/or overall survival of the cancer patients before and after taking chemotherapy.

  3. Alfalfa breeding benefits from genomics of Medicago truncatula

    Directory of Open Access Journals (Sweden)

    Žilije Bernadet

    2010-01-01

    Full Text Available International programs aim at developing knowledge and tools in the model species Medicago truncatula. Genetic resources, DNA sequences, markers, genetic and physical maps are now publicly available. These efforts contribute to improve breeding schemes of crop species such as alfalfa. However, transfer of information from M. truncatula to alfalfa is not straightforward. The article reviews the gain given by the model species to better analyze genetic determinism of breeding traits in alfalfa. It also shows that investments in alfalfa genomics (DNA sequences, SNP development are needed to benefit from the model species.

  4. Development and feasibility testing of the Pediatric Emergency Discharge Interaction Coding Scheme.

    Science.gov (United States)

    Curran, Janet A; Taylor, Alexandra; Chorney, Jill; Porter, Stephen; Murphy, Andrea; MacPhee, Shannon; Bishop, Andrea; Haworth, Rebecca

    2017-08-01

    Discharge communication is an important aspect of high-quality emergency care. This study addresses the gap in knowledge on how to describe discharge communication in a paediatric emergency department (ED). The objective of this feasibility study was to develop and test a coding scheme to characterize discharge communication between health-care providers (HCPs) and caregivers who visit the ED with their children. The Pediatric Emergency Discharge Interaction Coding Scheme (PEDICS) and coding manual were developed following a review of the literature and an iterative refinement process involving HCP observations, inter-rater assessments and team consensus. The coding scheme was pilot-tested through observations of HCPs across a range of shifts in one urban paediatric ED. Overall, 329 patient observations were carried out across 50 observational shifts. Inter-rater reliability was evaluated in 16% of the observations. The final version of the PEDICS contained 41 communication elements. Kappa scores were greater than .60 for the majority of communication elements. The most frequently observed communication elements were under the Introduction node and the least frequently observed were under the Social Concerns node. HCPs initiated the majority of the communication. Pediatric Emergency Discharge Interaction Coding Scheme addresses an important gap in the discharge communication literature. The tool is useful for mapping patterns of discharge communication between HCPs and caregivers. Results from our pilot test identified deficits in specific areas of discharge communication that could impact adherence to discharge instructions. The PEDICS would benefit from further testing with a different sample of HCPs. © 2017 The Authors. Health Expectations Published by John Wiley & Sons Ltd.

  5. Multiuser switched diversity scheduling schemes

    KAUST Repository

    Shaqfeh, Mohammad; Alnuweiri, Hussein M.; Alouini, Mohamed-Slim

    2012-01-01

    Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

  6. Short-Term Saved Leave Scheme

    CERN Multimedia

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new implementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme a...

  7. Short-Term Saved Leave Scheme

    CERN Multimedia

    HR Department

    2007-01-01

    As announced at the meeting of the Standing Concertation Committee (SCC) on 26 June 2007 and in http://Bulletin No. 28/2007, the existing Saved Leave Scheme will be discontinued as of 31 December 2007. Staff participating in the Scheme will shortly receive a contract amendment stipulating the end of financial contributions compensated by save leave. Leave already accumulated on saved leave accounts can continue to be taken in accordance with the rules applicable to the current scheme. A new system of saved leave will enter into force on 1 January 2008 and will be the subject of a new im-plementation procedure entitled "Short-term saved leave scheme" dated 1 January 2008. At its meeting on 4 December 2007, the SCC agreed to recommend the Director-General to approve this procedure, which can be consulted on the HR Department’s website at the following address: https://cern.ch/hr-services/services-Ben/sls_shortterm.asp All staff wishing to participate in the new scheme ...

  8. Multiuser switched diversity scheduling schemes

    KAUST Repository

    Shaqfeh, Mohammad

    2012-09-01

    Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

  9. Dealing with equality and benefit for water allocation in a lake watershed: A Gini-coefficient based stochastic optimization approach

    Science.gov (United States)

    Dai, C.; Qin, X. S.; Chen, Y.; Guo, H. C.

    2018-06-01

    A Gini-coefficient based stochastic optimization (GBSO) model was developed by integrating the hydrological model, water balance model, Gini coefficient and chance-constrained programming (CCP) into a general multi-objective optimization modeling framework for supporting water resources allocation at a watershed scale. The framework was advantageous in reflecting the conflicting equity and benefit objectives for water allocation, maintaining the water balance of watershed, and dealing with system uncertainties. GBSO was solved by the non-dominated sorting Genetic Algorithms-II (NSGA-II), after the parameter uncertainties of the hydrological model have been quantified into the probability distribution of runoff as the inputs of CCP model, and the chance constraints were converted to the corresponding deterministic versions. The proposed model was applied to identify the Pareto optimal water allocation schemes in the Lake Dianchi watershed, China. The optimal Pareto-front results reflected the tradeoff between system benefit (αSB) and Gini coefficient (αG) under different significance levels (i.e. q) and different drought scenarios, which reveals the conflicting nature of equity and efficiency in water allocation problems. A lower q generally implies a lower risk of violating the system constraints and a worse drought intensity scenario corresponds to less available water resources, both of which would lead to a decreased system benefit and a less equitable water allocation scheme. Thus, the proposed modeling framework could help obtain the Pareto optimal schemes under complexity and ensure that the proposed water allocation solutions are effective for coping with drought conditions, with a proper tradeoff between system benefit and water allocation equity.

  10. Numerical schemes for explosion hazards

    International Nuclear Information System (INIS)

    Therme, Nicolas

    2015-01-01

    In nuclear facilities, internal or external explosions can cause confinement breaches and radioactive materials release in the environment. Hence, modeling such phenomena is crucial for safety matters. Blast waves resulting from explosions are modeled by the system of Euler equations for compressible flows, whereas Navier-Stokes equations with reactive source terms and level set techniques are used to simulate the propagation of flame front during the deflagration phase. The purpose of this thesis is to contribute to the creation of efficient numerical schemes to solve these complex models. The work presented here focuses on two major aspects: first, the development of consistent schemes for the Euler equations, then the buildup of reliable schemes for the front propagation. In both cases, explicit in time schemes are used, but we also introduce a pressure correction scheme for the Euler equations. Staggered discretization is used in space. It is based on the internal energy formulation of the Euler system, which insures its positivity and avoids tedious discretization of the total energy over staggered grids. A discrete kinetic energy balance is derived from the scheme and a source term is added in the discrete internal energy balance equation to preserve the exact total energy balance at the limit. High order methods of MUSCL type are used in the discrete convective operators, based solely on material velocity. They lead to positivity of density and internal energy under CFL conditions. This ensures that the total energy cannot grow and we can furthermore derive a discrete entropy inequality. Under stability assumptions of the discrete L8 and BV norms of the scheme's solutions one can prove that a sequence of converging discrete solutions necessarily converges towards the weak solution of the Euler system. Besides it satisfies a weak entropy inequality at the limit. Concerning the front propagation, we transform the flame front evolution equation (the so called

  11. Compact Spreader Schemes

    Energy Technology Data Exchange (ETDEWEB)

    Placidi, M.; Jung, J. -Y.; Ratti, A.; Sun, C.

    2014-07-25

    This paper describes beam distribution schemes adopting a novel implementation based on low amplitude vertical deflections combined with horizontal ones generated by Lambertson-type septum magnets. This scheme offers substantial compactness in the longitudinal layouts of the beam lines and increased flexibility for beam delivery of multiple beam lines on a shot-to-shot basis. Fast kickers (FK) or transverse electric field RF Deflectors (RFD) provide the low amplitude deflections. Initially proposed at the Stanford Linear Accelerator Center (SLAC) as tools for beam diagnostics and more recently adopted for multiline beam pattern schemes, RFDs offer repetition capabilities and a likely better amplitude reproducibility when compared to FKs, which, in turn, offer more modest financial involvements both in construction and operation. Both solutions represent an ideal approach for the design of compact beam distribution systems resulting in space and cost savings while preserving flexibility and beam quality.

  12. Broadening of Distribution of Trap States in PbS Quantum Dot Field-Effect Transistors with High-k Dielectrics.

    Science.gov (United States)

    Nugraha, Mohamad I; Häusermann, Roger; Watanabe, Shun; Matsui, Hiroyuki; Sytnyk, Mykhailo; Heiss, Wolfgang; Takeya, Jun; Loi, Maria A

    2017-02-08

    We perform a quantitative analysis of the trap density of states (trap DOS) in PbS quantum dot field-effect transistors (QD-FETs), which utilize several polymer gate insulators with a wide range of dielectric constants. With increasing gate dielectric constant, we observe increasing trap DOS close to the lowest unoccupied molecular orbital (LUMO) of the QDs. In addition, this increase is also consistently followed by broadening of the trap DOS. We rationalize that the increase and broadening of the spectral trap distribution originate from dipolar disorder as well as polaronic interactions, which are appearing at strong dielectric polarization. Interestingly, the increased polaron-induced traps do not show any negative effect on the charge carrier mobility in our QD devices at the highest applied gate voltage, giving the possibility to fabricate efficient low-voltage QD devices without suppressing carrier transport.

  13. Speech reception with different bilateral directional processing schemes: Influence of binaural hearing, audiometric asymmetry, and acoustic scenario.

    Science.gov (United States)

    Neher, Tobias; Wagener, Kirsten C; Latzel, Matthias

    2017-09-01

    Hearing aid (HA) users can differ markedly in their benefit from directional processing (or beamforming) algorithms. The current study therefore investigated candidacy for different bilateral directional processing schemes. Groups of elderly listeners with symmetric (N = 20) or asymmetric (N = 19) hearing thresholds for frequencies below 2 kHz, a large spread in the binaural intelligibility level difference (BILD), and no difference in age, overall degree of hearing loss, or performance on a measure of selective attention took part. Aided speech reception was measured using virtual acoustics together with a simulation of a linked pair of completely occluding behind-the-ear HAs. Five processing schemes and three acoustic scenarios were used. The processing schemes differed in the tradeoff between signal-to-noise ratio (SNR) improvement and binaural cue preservation. The acoustic scenarios consisted of a frontal target talker presented against two speech maskers from ±60° azimuth or spatially diffuse cafeteria noise. For both groups, a significant interaction between BILD, processing scheme, and acoustic scenario was found. This interaction implied that, in situations with lateral speech maskers, HA users with BILDs larger than about 2 dB profited more from preserved low-frequency binaural cues than from greater SNR improvement, whereas for smaller BILDs the opposite was true. Audiometric asymmetry reduced the influence of binaural hearing. In spatially diffuse noise, the maximal SNR improvement was generally beneficial. N 0 S π detection performance at 500 Hz predicted the benefit from low-frequency binaural cues. Together, these findings provide a basis for adapting bilateral directional processing to individual and situational influences. Further research is needed to investigate their generalizability to more realistic HA conditions (e.g., with low-frequency vent-transmitted sound). Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Quantum signature scheme for known quantum messages

    International Nuclear Information System (INIS)

    Kim, Taewan; Lee, Hyang-Sook

    2015-01-01

    When we want to sign a quantum message that we create, we can use arbitrated quantum signature schemes which are possible to sign for not only known quantum messages but also unknown quantum messages. However, since the arbitrated quantum signature schemes need the help of a trusted arbitrator in each verification of the signature, it is known that the schemes are not convenient in practical use. If we consider only known quantum messages such as the above situation, there can exist a quantum signature scheme with more efficient structure. In this paper, we present a new quantum signature scheme for known quantum messages without the help of an arbitrator. Differing from arbitrated quantum signature schemes based on the quantum one-time pad with the symmetric key, since our scheme is based on quantum public-key cryptosystems, the validity of the signature can be verified by a receiver without the help of an arbitrator. Moreover, we show that our scheme provides the functions of quantum message integrity, user authentication and non-repudiation of the origin as in digital signature schemes. (paper)

  15. Two-level schemes for the advection equation

    Science.gov (United States)

    Vabishchevich, Petr N.

    2018-06-01

    The advection equation is the basis for mathematical models of continuum mechanics. In the approximate solution of nonstationary problems it is necessary to inherit main properties of the conservatism and monotonicity of the solution. In this paper, the advection equation is written in the symmetric form, where the advection operator is the half-sum of advection operators in conservative (divergent) and non-conservative (characteristic) forms. The advection operator is skew-symmetric. Standard finite element approximations in space are used. The standard explicit two-level scheme for the advection equation is absolutely unstable. New conditionally stable regularized schemes are constructed, on the basis of the general theory of stability (well-posedness) of operator-difference schemes, the stability conditions of the explicit Lax-Wendroff scheme are established. Unconditionally stable and conservative schemes are implicit schemes of the second (Crank-Nicolson scheme) and fourth order. The conditionally stable implicit Lax-Wendroff scheme is constructed. The accuracy of the investigated explicit and implicit two-level schemes for an approximate solution of the advection equation is illustrated by the numerical results of a model two-dimensional problem.

  16. Optimal Sales Schemes for Network Goods

    DEFF Research Database (Denmark)

    Parakhonyak, Alexei; Vikander, Nick

    consumers simultaneously, serve them all sequentially, or employ any intermediate scheme. We show that the optimal sales scheme is purely sequential, where each consumer observes all previous sales before choosing whether to buy himself. A sequential scheme maximizes the amount of information available...

  17. Is ‘making work pay’ effective for the ‘unemployable’? The impact of benefit sanctions on social assistance recipients in Denmark

    DEFF Research Database (Denmark)

    Diop-Christensen, Anna

    2015-01-01

    . This study evaluates how this policy influenced their transitions to employment and other benefit schemes by applying a competing risk duration model on Danish administrative data. The results show that the new rules not only had the anticipated impact on the women concerned, but the policy also had......In spring 2006, the Danish government introduced a policy that required married long-term social assistance recipients to work 300 hours in non-subsidised employment during a 2-year period in order to remain eligible for benefits. The intention was to ‘make work pay’ for unemployed immigrant women...... an unforeseen effect on the work effort of social welfare workers. Many moved their clients to other benefit schemes instead of applying the sanctions. This was particularly the case for the weakest among the unemployed and in municipalities, which were headed by left-wing mayors or that received extra funds...

  18. A magnet lattice for a tau-charm factory suitable for both standard scheme and monochromatization scheme

    International Nuclear Information System (INIS)

    Beloshitsky, P.

    1992-06-01

    A versatile magnet lattice for a tau-charm factory is considered in this report. The main feature of this lattice is the possibility to use it for both standard flat beam scheme and beam monochromatization scheme. The detailed description of the lattice is given. The restrictions following the compatibility of both schemes are discussed

  19. Extension of Pairwise Broadcast Clock Synchronization for Multicluster Sensor Networks

    Directory of Open Access Journals (Sweden)

    Bruce W. Suter

    2008-01-01

    Full Text Available Time synchronization is crucial for wireless sensor networks (WSNs in performing a number of fundamental operations such as data coordination, power management, security, and localization. The Pairwise Broadcast Synchronization (PBS protocol was recently proposed to minimize the number of timing messages required for global network synchronization, which enables the design of highly energy-efficient WSNs. However, PBS requires all nodes in the network to lie within the communication ranges of two leader nodes, a condition which might not be available in some applications. This paper proposes an extension of PBS to the more general class of sensor networks. Based on the hierarchical structure of the network, an energy-efficient pair selection algorithm is proposed to select the best pairwise synchronization sequence to reduce the overall energy consumption. It is shown that in a multicluster networking environment, PBS requires a far less number of timing messages than other well-known synchronization protocols and incurs no loss in synchronization accuracy. Moreover, the proposed scheme presents significant energy savings for densely deployed WSNs.

  20. A new hybrid numerical scheme for modelling elastodynamics in unbounded media with near-source heterogeneities

    Science.gov (United States)

    Hajarolasvadi, Setare; Elbanna, Ahmed E.

    2017-11-01

    The finite difference (FD) and the spectral boundary integral (SBI) methods have been used extensively to model spontaneously-propagating shear cracks in a variety of engineering and geophysical applications. In this paper, we propose a new modelling approach in which these two methods are combined through consistent exchange of boundary tractions and displacements. Benefiting from the flexibility of FD and the efficiency of SBI methods, the proposed hybrid scheme will solve a wide range of problems in a computationally efficient way. We demonstrate the validity of the approach using two examples for dynamic rupture propagation: one in the presence of a low-velocity layer and the other in which off-fault plasticity is permitted. We discuss possible potential uses of the hybrid scheme in earthquake cycle simulations as well as an exact absorbing boundary condition.

  1. THROUGHPUT ANALYSIS OF EXTENDED ARQ SCHEMES

    African Journals Online (AJOL)

    PUBLICATIONS1

    ABSTRACT. Various Automatic Repeat Request (ARQ) schemes have been used to combat errors that befall in- formation transmitted in digital communication systems. Such schemes include simple ARQ, mixed mode ARQ and Hybrid ARQ (HARQ). In this study we introduce extended ARQ schemes and derive.

  2. Ponzi scheme diffusion in complex networks

    Science.gov (United States)

    Zhu, Anding; Fu, Peihua; Zhang, Qinghe; Chen, Zhenyue

    2017-08-01

    Ponzi schemes taking the form of Internet-based financial schemes have been negatively affecting China's economy for the last two years. Because there is currently a lack of modeling research on Ponzi scheme diffusion within social networks yet, we develop a potential-investor-divestor (PID) model to investigate the diffusion dynamics of Ponzi scheme in both homogeneous and inhomogeneous networks. Our simulation study of artificial and real Facebook social networks shows that the structure of investor networks does indeed affect the characteristics of dynamics. Both the average degree of distribution and the power-law degree of distribution will reduce the spreading critical threshold and will speed up the rate of diffusion. A high speed of diffusion is the key to alleviating the interest burden and improving the financial outcomes for the Ponzi scheme operator. The zero-crossing point of fund flux function we introduce proves to be a feasible index for reflecting the fast-worsening situation of fiscal instability and predicting the forthcoming collapse. The faster the scheme diffuses, the higher a peak it will reach and the sooner it will collapse. We should keep a vigilant eye on the harm of Ponzi scheme diffusion through modern social networks.

  3. Agent-based power sharing scheme for active hybrid power sources

    Science.gov (United States)

    Jiang, Zhenhua

    The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

  4. The Performance-based Funding Scheme of Universities

    Directory of Open Access Journals (Sweden)

    Juha KETTUNEN

    2016-05-01

    Full Text Available The purpose of this study is to analyse the effectiveness of the performance-based funding scheme of the Finnish universities that was adopted at the beginning of 2013. The political decision-makers expect that the funding scheme will create incentives for the universities to improve performance, but these funding schemes have largely failed in many other countries, primarily because public funding is only a small share of the total funding of universities. This study is interesting because Finnish universities have no tuition fees, unlike in many other countries, and the state allocates funding based on the objectives achieved. The empirical evidence of the graduation rates indicates that graduation rates increased when a new scheme was adopted, especially among male students, who have more room for improvement than female students. The new performance-based funding scheme allocates the funding according to the output-based indicators and limits the scope of strategic planning and the autonomy of the university. The performance-based funding scheme is transformed to the strategy map of the balanced scorecard. The new funding scheme steers universities in many respects but leaves the research and teaching skills to the discretion of the universities. The new scheme has also diminished the importance of the performance agreements between the university and the Ministry. The scheme increases the incentives for universities to improve the processes and structures in order to attain as much public funding as possible. It is optimal for the central administration of the university to allocate resources to faculties and other organisational units following the criteria of the performance-based funding scheme. The new funding scheme has made the universities compete with each other, because the total funding to the universities is allocated to each university according to the funding scheme. There is a tendency that the funding schemes are occasionally

  5. Towards a universal certification scheme for NDT personnel

    International Nuclear Information System (INIS)

    Barnett, David

    2009-01-01

    Australia has been involved in the United Nations Development Program (UNDP) in SE Asia since 1980. In doing so it has provided assistance to emerging nations in the region through training and skills development of nondestructive testing personnel. As a result of involvement in this program consensus was reached between nations that the way forward in terms of qualification and certification was to adopt the guidelines being developed by ISO Standards Committee, ISO TC 135 SC7 for a new international standards, ISO 9712. In doing so, the member countries of the IAEA/UN Development Project recognised the benefits that harmonisation of certification schemes would bring in promoting trade in the region and the recognition of the skills of NDT personnel. ISO 9712 was first issued in 1992. (author)

  6. A Classification Scheme for Literary Characters

    Directory of Open Access Journals (Sweden)

    Matthew Berry

    2017-10-01

    Full Text Available There is no established classification scheme for literary characters in narrative theory short of generic categories like protagonist vs. antagonist or round vs. flat. This is so despite the ubiquity of stock characters that recur across media, cultures, and historical time periods. We present here a proposal of a systematic psychological scheme for classifying characters from the literary and dramatic fields based on a modification of the Thomas-Kilmann (TK Conflict Mode Instrument used in applied studies of personality. The TK scheme classifies personality along the two orthogonal dimensions of assertiveness and cooperativeness. To examine the validity of a modified version of this scheme, we had 142 participants provide personality ratings for 40 characters using two of the Big Five personality traits as well as assertiveness and cooperativeness from the TK scheme. The results showed that assertiveness and cooperativeness were orthogonal dimensions, thereby supporting the validity of using a modified version of TK’s two-dimensional scheme for classifying characters.

  7. How can conceptual schemes change teaching?

    Science.gov (United States)

    Wickman, Per-Olof

    2012-03-01

    Lundqvist, Almqvist and Östman describe a teacher's manner of teaching and the possible consequences it may have for students' meaning making. In doing this the article examines a teacher's classroom practice by systematizing the teacher's transactions with the students in terms of certain conceptual schemes, namely the epistemological moves, educational philosophies and the selective traditions of this practice. In connection to their study one may ask how conceptual schemes could change teaching. This article examines how the relationship of the conceptual schemes produced by educational researchers to educational praxis has developed from the middle of the last century to today. The relationship is described as having been transformed in three steps: (1) teacher deficit and social engineering, where conceptual schemes are little acknowledged, (2) reflecting practitioners, where conceptual schemes are mangled through teacher practice to aid the choices of already knowledgeable teachers, and (3) the mangling of the conceptual schemes by researchers through practice with the purpose of revising theory.

  8. CdO necklace like nanobeads decorated with PbS nanoparticles: Room temperature LPG sensor

    Energy Technology Data Exchange (ETDEWEB)

    Sonawane, N.B. [Department of Physics, School of Physical Sciences, North Maharashtra University, Jalgaon, 425001 M.S. (India); K.A.M.P. & N.K.P. Science College, Pimpalner, Sakri, Dhule, M.S. (India); Baviskar, P.K. [Department of Physics, School of Physical Sciences, North Maharashtra University, Jalgaon, 425001 M.S. (India); Ahire, R.R. [S.G. Patil Science, Sakri, Dhule, M.S. (India); Sankapal, B.R., E-mail: brsankapal@gmail.com [Nano Materials and Device Laboratory, Department of Applied Physics, Visvesvaraya National Institute of Technology, South Ambazari Road, Nagpur, 440010 M.S. (India)

    2017-04-15

    Simple chemical route has been employed to grow interconnected nanobeads of CdO having necklace like structure through air annealing of cadmium hydroxide nanowires. This nanobeads of n-CdO with high surface area has been decorated with p-PbS nanoparticles resulting in the formation of nano-heterojunction which has been utilized effectively as room temperature liquefied petroleum gas (LPG) sensor. The room temperature gas response towards C{sub 2}H{sub 5}OH, Cl{sub 2}, NH{sub 3}, CO{sub 2} and LPG was investigated, among which LPG exhibits significant response. The maximum gas response of 51.10% is achieved with 94.54% stability upon exposure of 1176 ppm concentration of LPG at room temperature (27 °C). The resulting parameters like gas response, response and recovery time along with stability studies has been studied and results are discussed herein. - Highlights: • Conversion of Cd(OH){sub 2} nanowires to CdO nanonecklace by air annealing at 290 °C. • Decoration of PbS nanoparticles over CdO nanobeads by SILAR method. • Formation of n-CdO/p-PbS nano-heterojunction as room temperature LPG sensor. • Maximum gas response of 51.10% with 94.54% stability.

  9. Who pays and who benefits from health care? An assessment of equity in health care financing and benefit distribution in Tanzania.

    Science.gov (United States)

    Mtei, Gemini; Makawia, Suzan; Ally, Mariam; Kuwawenaruwa, August; Meheus, Filip; Borghi, Josephine

    2012-03-01

    Little is known about health system equity in Tanzania, whether in terms of distribution of the health care financing burden or distribution of health care benefits. This study undertook a combined analysis of both financing and benefit incidence to explore the distribution of health care benefits and financing burden across socio-economic groups. A system-wide analysis of benefits was undertaken, including benefits from all providers irrespective of ownership. The analysis used the household budget survey (HBS) from 2001, the most recent nationally representative survey data publicly available at the time, to analyse the distribution of health care payments through user fees, health insurance contributions [from the National Health Insurance Fund (NHIF) for the formal sector and the Community Health Fund (CHF), for the rural informal sector] and taxation. Due to lack of information on NHIF and CHF contributions in the HBS, a primary survey was administered to estimate CHF enrollment and contributions; assumptions were used to estimate NHIF contributions within the HBS. Data from the same household survey, administered to 2224 households in seven districts/councils, was used to analyse the distribution of health care benefits across socio-economic groups. The health financing system was mildly progressive overall, with income taxes and NHIF contributions being the most progressive financing sources. Out-of-pocket payments and contributions to the CHF were regressive. The health benefit distribution was fairly even but the poorest received a lower share of benefits relative to their share of need for health care. Public primary care facility use was pro-poor, whereas higher level and higher cost facility use was generally pro-rich. We conclude that health financing reforms can improve equity, so long as integration of health insurance schemes is promoted along with cross-subsidization and greater reliance on general taxation to finance health care for the poorest.

  10. An Arbitrated Quantum Signature Scheme without Entanglement*

    International Nuclear Information System (INIS)

    Li Hui-Ran; Luo Ming-Xing; Peng Dai-Yuan; Wang Xiao-Jun

    2017-01-01

    Several quantum signature schemes are recently proposed to realize secure signatures of quantum or classical messages. Arbitrated quantum signature as one nontrivial scheme has attracted great interests because of its usefulness and efficiency. Unfortunately, previous schemes cannot against Trojan horse attack and DoS attack and lack of the unforgeability and the non-repudiation. In this paper, we propose an improved arbitrated quantum signature to address these secure issues with the honesty arbitrator. Our scheme takes use of qubit states not entanglements. More importantly, the qubit scheme can achieve the unforgeability and the non-repudiation. Our scheme is also secure for other known quantum attacks . (paper)

  11. Personalization, self-advocacy and inclusion: An evaluation of parent-initiated supported living schemes for people with intellectual and developmental disabilities in the Netherlands.

    Science.gov (United States)

    Reindl, Marie-Sol; Waltz, Mitzi; Schippers, Alice

    2016-06-01

    This study focused on parent-initiated supported living schemes in the South of the Netherlands and the ability of these living schemes to enhance participation, choice, autonomy and self-advocacy for people with intellectual or developmental disabilities through personalized planning, support and care. Based on in-depth interviews with tenants, parents and caregivers, findings included that parent-initiated supported housing schemes made steps towards stimulating self-advocacy and autonomy for tenants. However, overprotective and paternalistic attitudes expressed by a significant number of parents, as well as structural constraints affecting the living schemes, created obstacles to tenants' personal development. The study calls for consideration of interdependence as a model for the relationship of parents and adult offspring with disabilities. The benefits and tensions inherent within this relationship must be taken into consideration during inclusive community building. © The Author(s) 2016.

  12. AN ENSEMBLE TEMPLATE MATCHING AND CONTENT-BASED IMAGE RETRIEVAL SCHEME TOWARDS EARLY STAGE DETECTION OF MELANOMA

    Directory of Open Access Journals (Sweden)

    Spiros Kostopoulos

    2016-12-01

    Full Text Available Malignant melanoma represents the most dangerous type of skin cancer. In this study we present an ensemble classification scheme, employing the mutual information, the cross-correlation and the clustering based on proximity of image features methods, for early stage assessment of melanomas on plain photography images. The proposed scheme performs two main operations. First, it retrieves the most similar, to the unknown case, image samples from an available image database with verified benign moles and malignant melanoma cases. Second, it provides an automated estimation regarding the nature of the unknown image sample based on the majority of the most similar images retrieved from the available database. Clinical material comprised 75 melanoma and 75 benign plain photography images collected from publicly available dermatological atlases. Results showed that the ensemble scheme outperformed all other methods tested in terms of accuracy with 94.9±1.5%, following an external cross-validation evaluation methodology. The proposed scheme may benefit patients by providing a second opinion consultation during the self-skin examination process and the physician by providing a second opinion estimation regarding the nature of suspicious moles that may assist towards decision making especially for ambiguous cases, safeguarding, in this way from potential diagnostic misinterpretations.

  13. Improving the Performance of PbS Quantum Dot Solar Cells by Optimizing ZnO Window Layer

    Science.gov (United States)

    Yang, Xiaokun; Hu, Long; Deng, Hui; Qiao, Keke; Hu, Chao; Liu, Zhiyong; Yuan, Shengjie; Khan, Jahangeer; Li, Dengbing; Tang, Jiang; Song, Haisheng; Cheng, Chun

    2017-04-01

    Comparing with hot researches in absorber layer, window layer has attracted less attention in PbS quantum dot solar cells (QD SCs). Actually, the window layer plays a key role in exciton separation, charge drifting, and so on. Herein, ZnO window layer was systematically investigated for its roles in QD SCs performance. The physical mechanism of improved performance was also explored. It was found that the optimized ZnO films with appropriate thickness and doping concentration can balance the optical and electrical properties, and its energy band align well with the absorber layer for efficient charge extraction. Further characterizations demonstrated that the window layer optimization can help to reduce the surface defects, improve the heterojunction quality, as well as extend the depletion width. Compared with the control devices, the optimized devices have obtained an efficiency of 6.7% with an enhanced V oc of 18%, J sc of 21%, FF of 10%, and power conversion efficiency of 58%. The present work suggests a useful strategy to improve the device performance by optimizing the window layer besides the absorber layer.

  14. Breeding schemes in reindeer husbandry

    Directory of Open Access Journals (Sweden)

    Lars Rönnegård

    2003-04-01

    Full Text Available The objective of the paper was to investigate annual genetic gain from selection (G, and the influence of selection on the inbreeding effective population size (Ne, for different possible breeding schemes within a reindeer herding district. The breeding schemes were analysed for different proportions of the population within a herding district included in the selection programme. Two different breeding schemes were analysed: an open nucleus scheme where males mix and mate between owner flocks, and a closed nucleus scheme where the males in non-selected owner flocks are culled to maximise G in the whole population. The theory of expected long-term genetic contributions was used and maternal effects were included in the analyses. Realistic parameter values were used for the population, modelled with 5000 reindeer in the population and a sex ratio of 14 adult females per male. The standard deviation of calf weights was 4.1 kg. Four different situations were explored and the results showed: 1. When the population was randomly culled, Ne equalled 2400. 2. When the whole population was selected on calf weights, Ne equalled 1700 and the total annual genetic gain (direct + maternal in calf weight was 0.42 kg. 3. For the open nucleus scheme, G increased monotonically from 0 to 0.42 kg as the proportion of the population included in the selection programme increased from 0 to 1.0, and Ne decreased correspondingly from 2400 to 1700. 4. In the closed nucleus scheme the lowest value of Ne was 1300. For a given proportion of the population included in the selection programme, the difference in G between a closed nucleus scheme and an open one was up to 0.13 kg. We conclude that for mass selection based on calf weights in herding districts with 2000 animals or more, there are no risks of inbreeding effects caused by selection.

  15. Quantum Secure Communication Scheme with W State

    International Nuclear Information System (INIS)

    Wang Jian; Zhang Quan; Tang Chaojng

    2007-01-01

    We present a quantum secure communication scheme using three-qubit W state. It is unnecessary for the present scheme to use alternative measurement or Bell basis measurement. Compared with the quantum secure direct communication scheme proposed by Cao et al. [H.J. Cao and H.S. Song, Chin. Phys. Lett. 23 (2006) 290], in our scheme, the detection probability for an eavesdropper's attack increases from 8.3% to 25%. We also show that our scheme is secure for a noise quantum channel.

  16. Geographic variation in health insurance benefits in Qianjiang District, China: a cross-sectional study.

    Science.gov (United States)

    Wu, Yue; Zhang, Liang; Liu, Xuejiao; Ye, Ting; Wang, Yongfei

    2018-02-05

    Health insurance contributes to reducing the economic burden of disease and improving access to healthcare. In 2016, the Chinese government announced the integration of the New Cooperative Medical Scheme (NCMS) and Urban Resident Basic Medical Insurance (URBMI) to reduce system segmentation. Nevertheless, it was unclear whether there would be any geographic variation in health insurance benefits if the two types of insurance were integrated. The aim of this study was to identify the potential geographic variation in health insurance benefits and the related contributing factors. This cross-sectional study was carried out in Qianjiang District, where the NCMS and URBMI were integrated into Urban and Rural Resident Basic Medical Insurance Scheme (URRBMI) in 2010. All beneficiaries under the URRBMI were hospitalized at least once in 2013, totaling 445,254 persons and 65,877 person-times, were included in this study. Town-level data on health insurance benefits, healthcare utilization, and socioeconomic and geographical characteristics were collected through health insurance system, self-report questionnaires, and the 2014 Statistical Yearbook of Qianjiang District. A simplified Theil index at town level was calculated to measure geographic variation in health insurance benefits. Colored maps were created to visualize the variation in geographic distribution of benefits. The effects of healthcare utilization and socioeconomic and geographical characteristics on geographic variation in health insurance benefits were estimated with a multiple linear regression analysis. Different Theil index values were calculated for different towns, and the Theil index values for compensation by person-times and amount were 2.5028 and 1.8394 in primary healthcare institutions and 1.1466 and 0.9204 in secondary healthcare institutions. Healthcare-seeking behavior and economic factors were positively associated with health insurance benefits in compensation by person-times significantly

  17. An assessment of innovative pricing schemes for the communication of value: is price discrimination and two-part pricing a way forward?

    Science.gov (United States)

    Hertzman, Peter; Miller, Paul; Tolley, Keith

    2018-02-01

    With the introduction of new expensive medicines, traditional pricing schemes based on constructs such as price per pill/vial have been challenged. Potential innovative schemes could be either financial-based or performance-based. Within financial-based schemes the use of price discrimination is an emerging option, which we explore in this assessment. Areas covered: In the short term the price per indication approach is likely to become more prevalent for high cost, high benefit new pharmaceuticals, such as those emerging in oncology (e.g. new combination immunotherapies). 'Two-Part Pricing' (2PP) is a frequently used payment method in other industries, which consists of an Entry Fee, giving the buyer the right to use the product, and a Usage Price charged every time the product is purchased. Introducing 2PP into biopharma could have cross-stakeholder benefits including broader patient access, and improvement in budget/revenue predictability. A concern however is the potential complexity of the negotiation between manufacturer and payer. Expert commentary: We believe 'price discrimination' and 2PP in particular can be relevant for some new, expensive specialist medicines. A recommended first step would be to initiate pilots to test to what degree the 2PP approach meets stakeholder objectives and is practical to implement within specialty care.

  18. Optimum RA reactor fuelling scheme

    International Nuclear Information System (INIS)

    Strugar, P.; Nikolic, V.

    1965-10-01

    Ideal reactor refueling scheme can be achieved only by continuous fuel elements movement in the core, which is not possible, and thus approximations are applied. One of the possible approximations is discontinuous movement of fuel elements groups in radial direction. This enables higher burnup especially if axial exchange is possible. Analysis of refueling schemes in the RA reactor core and schemes with mixing the fresh and used fuel elements show that 30% higher burnup can be achieved by applying mixing, and even 40% if reactivity due to decrease in experimental space is taken into account. Up to now, mean burnup of 4400 MWd/t has been achieved, and the proposed fueling scheme with reduction of experimental space could achieve mean burnup of 6300 MWd/t which means about 25 Mwd/t per fuel channel [sr

  19. A European-wide harmonised tradable green certificate scheme for renewable electricity: is it really so beneficial?

    International Nuclear Information System (INIS)

    Rio, Pablo del

    2005-01-01

    Winds of change are blowing in the public promotion of renewable electricity (RES-E) in Europe. On the one hand, a move to allegedly more market-conform instruments for the promotion of RES-E has already taken place in some Member States. On the other hand, a Directive on the promotion of RES-E has recently been approved setting indicative targets for RES-E consumption and opening the possibility that a harmonised framework for support schemes will be implemented in Europe. This harmonised framework (in combination with trade in RES-E between Member States) can be compared to a situation in which Member States continue to apply their current support schemes. This paper analyses the pros and cons of harmonisation. The main conclusion is that if priority is given to the local/regional/national benefits of RES-E, then harmonisation in combination with a tradable green certificate scheme is not so advantageous for countries. Only if the policy priority is the achievement of the RES-E Directive targets at the minimum costs should harmonisation be favoured by national energy authorities

  20. Student’s scheme in solving mathematics problems

    Science.gov (United States)

    Setyaningsih, Nining; Juniati, Dwi; Suwarsono

    2018-03-01

    The purpose of this study was to investigate students’ scheme in solving mathematics problems. Scheme are data structures for representing the concepts stored in memory. In this study, we used it in solving mathematics problems, especially ratio and proportion topics. Scheme is related to problem solving that assumes that a system is developed in the human mind by acquiring a structure in which problem solving procedures are integrated with some concepts. The data were collected by interview and students’ written works. The results of this study revealed are students’ scheme in solving the problem of ratio and proportion as follows: (1) the content scheme, where students can describe the selected components of the problem according to their prior knowledge, (2) the formal scheme, where students can explain in construct a mental model based on components that have been selected from the problem and can use existing schemes to build planning steps, create something that will be used to solve problems and (3) the language scheme, where students can identify terms, or symbols of the components of the problem.Therefore, by using the different strategies to solve the problems, the students’ scheme in solving the ratio and proportion problems will also differ.

  1. hybrid modulation scheme fo rid modulation scheme fo dulation

    African Journals Online (AJOL)

    eobe

    control technique is done through simulations and ex control technique .... HYBRID MODULATION SCHEME FOR CASCADED H-BRIDGE INVERTER CELLS. C. I. Odeh ..... and OR operations. Referring to ... MATLAB/SIMULINK environment.

  2. Towards Symbolic Encryption Schemes

    DEFF Research Database (Denmark)

    Ahmed, Naveed; Jensen, Christian D.; Zenner, Erik

    2012-01-01

    , namely an authenticated encryption scheme that is secure under chosen ciphertext attack. Therefore, many reasonable encryption schemes, such as AES in the CBC or CFB mode, are not among the implementation options. In this paper, we report new attacks on CBC and CFB based implementations of the well......Symbolic encryption, in the style of Dolev-Yao models, is ubiquitous in formal security models. In its common use, encryption on a whole message is specified as a single monolithic block. From a cryptographic perspective, however, this may require a resource-intensive cryptographic algorithm......-known Needham-Schroeder and Denning-Sacco protocols. To avoid such problems, we advocate the use of refined notions of symbolic encryption that have natural correspondence to standard cryptographic encryption schemes....

  3. A counterfactual p-value approach for benefit-risk assessment in clinical trials.

    Science.gov (United States)

    Zeng, Donglin; Chen, Ming-Hui; Ibrahim, Joseph G; Wei, Rachel; Ding, Beiying; Ke, Chunlei; Jiang, Qi

    2015-01-01

    Clinical trials generally allow various efficacy and safety outcomes to be collected for health interventions. Benefit-risk assessment is an important issue when evaluating a new drug. Currently, there is a lack of standardized and validated benefit-risk assessment approaches in drug development due to various challenges. To quantify benefits and risks, we propose a counterfactual p-value (CP) approach. Our approach considers a spectrum of weights for weighting benefit-risk values and computes the extreme probabilities of observing the weighted benefit-risk value in one treatment group as if patients were treated in the other treatment group. The proposed approach is applicable to single benefit and single risk outcome as well as multiple benefit and risk outcomes assessment. In addition, the prior information in the weight schemes relevant to the importance of outcomes can be incorporated in the approach. The proposed CPs plot is intuitive with a visualized weight pattern. The average area under CP and preferred probability over time are used for overall treatment comparison and a bootstrap approach is applied for statistical inference. We assess the proposed approach using simulated data with multiple efficacy and safety endpoints and compare its performance with a stochastic multi-criteria acceptability analysis approach.

  4. Setting aside transactions from pyramid schemes as impeachable ...

    African Journals Online (AJOL)

    These schemes, which are often referred to as pyramid or Ponzi schemes, are unsustainable operations and give rise to problems in the law of insolvency. Investors in these schemes are often left empty-handed upon the scheme's eventual collapse and insolvency. Investors who received pay-outs from the scheme find ...

  5. Assessment of remedial control schemes for damping transient oscillations in the Mexican system

    Energy Technology Data Exchange (ETDEWEB)

    Castellanos, R.B.; Sarmiento, H.U.; Pampin, G. [Inst.de Investigaciones Electricas, Morelos (Mexico); Messina, A.R. [Cinvestav, San Pedro Zacatenco (Mexico)

    2008-07-01

    In order to enhance voltage control and power system dynamic performance, special protection systems (SPS) are increasingly being used in the Mexican Interconnected System (MIS). These include extensive use of direct load shedding schemes, generator tripping schemes, controlled disconnection of lines, and automatic generation rejection and single phase reclosing schemes. Generator tripping based on local detection of severe disturbance is of particular importance and has been used to enhance transient stability. In addition, the onset of system instability has become more complex, often involving interactions between major system modes. Post-fault transient oscillations have become more common following the loss of major system elements and may result in uncontrolled system separation. This has motivated the need to develop system-wide special protection systems. This paper explored the possible benefits and feasibility of employing SPSs to mitigate wide-area inter-area oscillations in the MIS. The paper described the exploratory studies such as the coordinated application of automatic generation tripping schemes and automatic load shedding to enhance system dynamic performance. The paper also explained sensitivity studies that were conducted to determine the amount and location of generation (load) to be shed and suggested extensions to the basic security criteria to maintain network stability. The proposed techniques were developed and tested on a large-scale representation of the Mexican system that included the operation of several FACTS controllers. It was concluded that automatic generation shedding and automatic loading shedding were efficient alternatives to improve generation and transmission use, reliability and flexibility. 7 refs., 1 tab., 3 figs.

  6. Renormalization scheme-invariant perturbation theory

    International Nuclear Information System (INIS)

    Dhar, A.

    1983-01-01

    A complete solution to the problem of the renormalization scheme dependence of perturbative approximants to physical quantities is presented. An equation is derived which determines any physical quantity implicitly as a function of only scheme independent variables. (orig.)

  7. Nonlinear secret image sharing scheme.

    Science.gov (United States)

    Shin, Sang-Ho; Lee, Gil-Je; Yoo, Kee-Young

    2014-01-01

    Over the past decade, most of secret image sharing schemes have been proposed by using Shamir's technique. It is based on a linear combination polynomial arithmetic. Although Shamir's technique based secret image sharing schemes are efficient and scalable for various environments, there exists a security threat such as Tompa-Woll attack. Renvall and Ding proposed a new secret sharing technique based on nonlinear combination polynomial arithmetic in order to solve this threat. It is hard to apply to the secret image sharing. In this paper, we propose a (t, n)-threshold nonlinear secret image sharing scheme with steganography concept. In order to achieve a suitable and secure secret image sharing scheme, we adapt a modified LSB embedding technique with XOR Boolean algebra operation, define a new variable m, and change a range of prime p in sharing procedure. In order to evaluate efficiency and security of proposed scheme, we use the embedding capacity and PSNR. As a result of it, average value of PSNR and embedding capacity are 44.78 (dB) and 1.74t⌈log2 m⌉ bit-per-pixel (bpp), respectively.

  8. Industrial Cost-Benefit Assessment for Fault-tolerant Control Systems

    DEFF Research Database (Denmark)

    Thybo, C.; Blanke, M.

    1998-01-01

    Economic aspects are decisive for industrial acceptance of research concepts including the promising ideas in fault tolerant control. Fault tolerance is the ability of a system to detect, isolate and accommodate a fault, such that simple faults in a sub-system do not develop into failures....... The objective of this paper is to help, in the early product development state, to find the economical most suitable scheme. A salient result is that with increased customer awareness of total cost of ownership, new products can benefit significantly from applying fault tolerant control principles....

  9. Good governance for pension schemes

    CERN Document Server

    Thornton, Paul

    2011-01-01

    Regulatory and market developments have transformed the way in which UK private sector pension schemes operate. This has increased demands on trustees and advisors and the trusteeship governance model must evolve in order to remain fit for purpose. This volume brings together leading practitioners to provide an overview of what today constitutes good governance for pension schemes, from both a legal and a practical perspective. It provides the reader with an appreciation of the distinctive characteristics of UK occupational pension schemes, how they sit within the capital markets and their social and fiduciary responsibilities. Providing a holistic analysis of pension risk, both from the trustee and the corporate perspective, the essays cover the crucial role of the employer covenant, financing and investment risk, developments in longevity risk hedging and insurance de-risking, and best practice scheme administration.

  10. Scheme for secure swapping two unknown states of a photonic qubit and an electron-spin qubit using simultaneous quantum transmission and teleportation via quantum dots inside single-sided optical cavities

    Energy Technology Data Exchange (ETDEWEB)

    Heo, Jino [College of Electrical and Computer Engineering, Chungbuk National University, Chungdae-ro 1, Seowon-Gu, Cheongju (Korea, Republic of); Kang, Min-Sung [Center for Quantum Information, Korea Institute of Science and Technology (KIST), Seoul, 136-791 (Korea, Republic of); Hong, Chang-Ho [National Security Research Institute, P.O.Box 1, Yuseong, Daejeon, 34188 (Korea, Republic of); Choi, Seong-Gon [College of Electrical and Computer Engineering, Chungbuk National University, Chungdae-ro 1, Seowon-Gu, Cheongju (Korea, Republic of); Hong, Jong-Phil, E-mail: jongph@cbnu.ac.kr [College of Electrical and Computer Engineering, Chungbuk National University, Chungdae-ro 1, Seowon-Gu, Cheongju (Korea, Republic of)

    2017-06-15

    We propose a scheme for swapping two unknown states of a photon and electron spin confined to a charged quantum dot (QD) between two users by transferring a single photon. This scheme simultaneously transfers and teleports an unknown state (electron spin) between two users. For this bidirectional quantum communication, we utilize the interactions between a photonic and an electron-spin qubits of a QD located inside a single-sided optical cavity. Thus, our proposal using QD-cavity systems can obtain a certain success probability with high fidelity. Furthermore, compared to a previous scheme using cross-Kerr nonlinearities and homodyne detections, our scheme (using QD-cavity systems) can improve the feasibility under the decoherence effect in practice. - Highlights: • Design of Simultaneous quantum transmission and teleportation scheme via quantum dots and cavities. • We have developed the experimental feasibility of this scheme compared with the existing scheme. • Analysis of some benefits when our scheme is experimentally implemented using quantum dots and single-sided cavities.

  11. Symmetric weak ternary quantum homomorphic encryption schemes

    Science.gov (United States)

    Wang, Yuqi; She, Kun; Luo, Qingbin; Yang, Fan; Zhao, Chao

    2016-03-01

    Based on a ternary quantum logic circuit, four symmetric weak ternary quantum homomorphic encryption (QHE) schemes were proposed. First, for a one-qutrit rotation gate, a QHE scheme was constructed. Second, in view of the synthesis of a general 3 × 3 unitary transformation, another one-qutrit QHE scheme was proposed. Third, according to the one-qutrit scheme, the two-qutrit QHE scheme about generalized controlled X (GCX(m,n)) gate was constructed and further generalized to the n-qutrit unitary matrix case. Finally, the security of these schemes was analyzed in two respects. It can be concluded that the attacker can correctly guess the encryption key with a maximum probability pk = 1/33n, thus it can better protect the privacy of users’ data. Moreover, these schemes can be well integrated into the future quantum remote server architecture, and thus the computational security of the users’ private quantum information can be well protected in a distributed computing environment.

  12. Labelling schemes: From a consumer perspective

    DEFF Research Database (Denmark)

    Juhl, Hans Jørn; Stacey, Julia

    2000-01-01

    Labelling of food products attracts a lot of political attention these days. As a result of a number of food scandals, most European countries have acknowledged the need for more information and better protection of consumers. Labelling schemes are one way of informing and guiding consumers....... However, initiatives in relation to labelling schemes seldom take their point of departure in consumers' needs and expectations; and in many cases, the schemes are defined by the institutions guaranteeing the label. It is therefore interesting to study how consumers actually value labelling schemes....... A recent MAPP study has investigated the value consumers attach the Government-controlled labels 'Ø-mærket' and 'Den Blå Lup' and the private supermarket label 'Mesterhakket' when they purchase minced meat. The results reveal four consumer segments that use labelling schemes for food products very...

  13. Analysis of central and upwind compact schemes

    International Nuclear Information System (INIS)

    Sengupta, T.K.; Ganeriwal, G.; De, S.

    2003-01-01

    Central and upwind compact schemes for spatial discretization have been analyzed with respect to accuracy in spectral space, numerical stability and dispersion relation preservation. A von Neumann matrix spectral analysis is developed here to analyze spatial discretization schemes for any explicit and implicit schemes to investigate the full domain simultaneously. This allows one to evaluate various boundary closures and their effects on the domain interior. The same method can be used for stability analysis performed for the semi-discrete initial boundary value problems (IBVP). This analysis tells one about the stability for every resolved length scale. Some well-known compact schemes that were found to be G-K-S and time stable are shown here to be unstable for selective length scales by this analysis. This is attributed to boundary closure and we suggest special boundary treatment to remove this shortcoming. To demonstrate the asymptotic stability of the resultant schemes, numerical solution of the wave equation is compared with analytical solution. Furthermore, some of these schemes are used to solve two-dimensional Navier-Stokes equation and a computational acoustic problem to check their ability to solve problems for long time. It is found that those schemes, that were found unstable for the wave equation, are unsuitable for solving incompressible Navier-Stokes equation. In contrast, the proposed compact schemes with improved boundary closure and an explicit higher-order upwind scheme produced correct results. The numerical solution for the acoustic problem is compared with the exact solution and the quality of the match shows that the used compact scheme has the requisite DRP property

  14. Axial shuffling fuel-management schemes for 1.2% SEU in CANDU

    International Nuclear Information System (INIS)

    Younis, M.H.; Boczar, P.G.

    1989-11-01

    The use of slightly enriched uranium (SEU) in CANDU (CANada Deuterium Uranium) requires a different fuel-management strategy than that usually employed with natural uranium fuel. Axial shuffling is a fuel-management strategy in which some or all of the fuel bundles are removed from the channel, rearranged, and reinserted into the same channel, along with fresh fuel. An axial shuffling scheme has been devised for 1.2% SEU which results in excellent power profiles, from the perspectives of both good axial flattening and power histories. With the CANFLEX (CANdu FLEXible fuelling) advanced fuel bundle, fuel rating can be reduced to below 40kW/m, with consequent safety benefits

  15. 1-Pb/s (32 SDM/46 WDM/768 Gb/s) C-band Dense SDM Transmission over 205.6-km of Single-mode Heterogeneous Multi-core Fiber using 96-Gbaud PDM-16QAM Channels

    DEFF Research Database (Denmark)

    Kobayashi, Takayuki; Nakamura, M.; Hamaoka, F.

    2017-01-01

    We demonstrate the first 1-Pb/s unidirectional inline-amplified transmission over 205.6-km of single-mode 32-core fiber within C-band only. 96-Gbaud LDPC-coded PDM-16QAM channels with FEC redundancy of 12.75% realize high-aggregate spectral efficiency of 217.6 b/s/Hz...

  16. A Novel Iris Segmentation Scheme

    Directory of Open Access Journals (Sweden)

    Chen-Chung Liu

    2014-01-01

    Full Text Available One of the key steps in the iris recognition system is the accurate iris segmentation from its surrounding noises including pupil, sclera, eyelashes, and eyebrows of a captured eye-image. This paper presents a novel iris segmentation scheme which utilizes the orientation matching transform to outline the outer and inner iris boundaries initially. It then employs Delogne-Kåsa circle fitting (instead of the traditional Hough transform to further eliminate the outlier points to extract a more precise iris area from an eye-image. In the extracted iris region, the proposed scheme further utilizes the differences in the intensity and positional characteristics of the iris, eyelid, and eyelashes to detect and delete these noises. The scheme is then applied on iris image database, UBIRIS.v1. The experimental results show that the presented scheme provides a more effective and efficient iris segmentation than other conventional methods.

  17. Analysis of Program Obfuscation Schemes with Variable Encoding Technique

    Science.gov (United States)

    Fukushima, Kazuhide; Kiyomoto, Shinsaku; Tanaka, Toshiaki; Sakurai, Kouichi

    Program analysis techniques have improved steadily over the past several decades, and software obfuscation schemes have come to be used in many commercial programs. A software obfuscation scheme transforms an original program or a binary file into an obfuscated program that is more complicated and difficult to analyze, while preserving its functionality. However, the security of obfuscation schemes has not been properly evaluated. In this paper, we analyze obfuscation schemes in order to clarify the advantages of our scheme, the XOR-encoding scheme. First, we more clearly define five types of attack models that we defined previously, and define quantitative resistance to these attacks. Then, we compare the security, functionality and efficiency of three obfuscation schemes with encoding variables: (1) Sato et al.'s scheme with linear transformation, (2) our previous scheme with affine transformation, and (3) the XOR-encoding scheme. We show that the XOR-encoding scheme is superior with regard to the following two points: (1) the XOR-encoding scheme is more secure against a data-dependency attack and a brute force attack than our previous scheme, and is as secure against an information-collecting attack and an inverse transformation attack as our previous scheme, (2) the XOR-encoding scheme does not restrict the calculable ranges of programs and the loss of efficiency is less than in our previous scheme.

  18. Efficient multiparty quantum-secret-sharing schemes

    International Nuclear Information System (INIS)

    Xiao Li; Deng Fuguo; Long Guilu; Pan Jianwei

    2004-01-01

    In this work, we generalize the quantum-secret-sharing scheme of Hillery, Buzek, and Berthiaume [Phys. Rev. A 59, 1829 (1999)] into arbitrary multiparties. Explicit expressions for the shared secret bit is given. It is shown that in the Hillery-Buzek-Berthiaume quantum-secret-sharing scheme the secret information is shared in the parity of binary strings formed by the measured outcomes of the participants. In addition, we have increased the efficiency of the quantum-secret-sharing scheme by generalizing two techniques from quantum key distribution. The favored-measuring-basis quantum-secret-sharing scheme is developed from the Lo-Chau-Ardehali technique [H. K. Lo, H. F. Chau, and M. Ardehali, e-print quant-ph/0011056] where all the participants choose their measuring-basis asymmetrically, and the measuring-basis-encrypted quantum-secret-sharing scheme is developed from the Hwang-Koh-Han technique [W. Y. Hwang, I. G. Koh, and Y. D. Han, Phys. Lett. A 244, 489 (1998)] where all participants choose their measuring basis according to a control key. Both schemes are asymptotically 100% in efficiency, hence nearly all the Greenberger-Horne-Zeilinger states in a quantum-secret-sharing process are used to generate shared secret information

  19. Synthesis and photoelectrical performance of nanoscale PbS and Bi2S3 co-sensitized on Ti02 nanotube arrays

    Institute of Scientific and Technical Information of China (English)

    Fanggong Cai; Min Pan; Yong Feng; Guo Yan; Yong Zhang; Yong Zhao

    2017-01-01

    TiO2 films have been widely applied in photovoltaic conversion techniques.TiO2 nanotube arrays (TiO2 NAs) can be grown directly on the surface of metal Ti by the anodic oxidation method.Bi2S3 and PbS nanoparticles (NPs) were firstly co-sensitized on TiO2 NAs (denoted as PbS/Bi2S3(n)/TiO2 NAs) by a two-step process containing hydrothermal and sonication-assisted SILAR method.When the concentration of Bi3+ is 5 mmol/L,the best photoelectrical performance was obtained under simulated solar irradiation.The short-circuit photocurrent (Jsc) and photoconversion efficiency (η) of PbS/Bi2S3(5)/TiO2 NAs electrode were 4.70 mA/cm and 1.13 %,respectively.

  20. Gamma spectrometry; level schemes

    International Nuclear Information System (INIS)

    Blachot, J.; Bocquet, J.P.; Monnand, E.; Schussler, F.

    1977-01-01

    The research presented dealt with: a new beta emitter, isomer of 131 Sn; the 136 I levels fed through the radioactive decay of 136 Te (20.9s); the A=145 chain (β decay of Ba, La and Ce, and level schemes for 145 La, 145 Ce, 145 Pr); the A=47 chain (La and Ce, β decay, and the level schemes of 147 Ce and 147 Pr) [fr

  1. Coordinated renewable energy support schemes

    DEFF Research Database (Denmark)

    Morthorst, P.E.; Jensen, S.G.

    2006-01-01

    . The first example covers countries with regional power markets that also regionalise their support schemes, the second countries with separate national power markets that regionalise their support schemes. The main findings indicate that the almost ideal situation exists if the region prior to regionalising...

  2. Asynchronous Channel-Hopping Scheme under Jamming Attacks

    Directory of Open Access Journals (Sweden)

    Yongchul Kim

    2018-01-01

    Full Text Available Cognitive radio networks (CRNs are considered an attractive technology to mitigate inefficiency in the usage of licensed spectrum. CRNs allow the secondary users (SUs to access the unused licensed spectrum and use a blind rendezvous process to establish communication links between SUs. In particular, quorum-based channel-hopping (CH schemes have been studied recently to provide guaranteed blind rendezvous in decentralized CRNs without using global time synchronization. However, these schemes remain vulnerable to jamming attacks. In this paper, we first analyze the limitations of quorum-based rendezvous schemes called asynchronous channel hopping (ACH. Then, we introduce a novel sequence sensing jamming attack (SSJA model in which a sophisticated jammer can dramatically reduce the rendezvous success rates of ACH schemes. In addition, we propose a fast and robust asynchronous rendezvous scheme (FRARS that can significantly enhance robustness under jamming attacks. Our numerical results demonstrate that the performance of the proposed scheme vastly outperforms the ACH scheme when there are security concerns about a sequence sensing jammer.

  3. Prostatic pathology reporting in the UK: development of a national external quality assurance scheme.

    Science.gov (United States)

    Harnden, P; Coleman, D; Moss, S; Kodikara, S; Patnick, J; Melia, J

    2008-01-01

    To develop a baseline picture of prostatic pathology reporting in the UK, identify areas of particular difficulty and assess the feasibility of a national external quality assurance scheme based on prostatic biopsy specimens using the same format as the National Health Service breast pathology scheme, as recommended by the National Institute for Clinical Excellence. Eight expert uropathologists and 32 randomly selected pathologists participated in four circulations each of 12 cases of prostatic biopsy specimens. A fixed text proforma was developed and responses were analysed for interobserver agreement using kappa statistics. Consistency of reporting the main diagnostic categories of benign and invasive carcinoma was good (kappa values 0.77 and 0.88, respectively), but only after excluding 19% of cases for which the experts did not reach 75% agreement. Areas of difficulty included the diagnosis of high-grade prostatic intraepithelial neoplasia and small foci of cancer. Prognostic factor reporting was more variable, with lower overall kappas for the assessment of Gleason grading (experts 0.55, others 0.50), perineural invasion (experts 0.64, others 0.50) and number of positive cores (experts 0.74, others 0.61). Given the difficulties in diagnosis of prostatic biopsy specimens and the assessment of prognostic factors, the expansion of the scheme could deliver important educational benefits.

  4. Digital Media for STEM Learning: Developing scientific practice skills in the K-12 STEM classroom with resources from WGBH and PBS LearningMedia

    Science.gov (United States)

    Foster, J.; Connolly, R.

    2017-12-01

    WGBH's "Bringing the Universe to America's Classrooms" project is a 5-year effort to design, produce and evaluate digital media tools and resources that support scientific practice skills in diverse K-12 learners. Resources leverage data and content from NASA and WGBH signature programs, like NOVA, into sound instructional experiences that provide K-12 STEM teachers with free, quality resources for teaching topics in the Earth and Space Sciences. Resources address the content and practices in the new K-12 Framework for Science Education and are aligned with the NGSS. Participants will learn about design strategies, findings from our evaluation efforts, and how to access free resources on PBS LearningMedia.

  5. A fast resonance interference treatment scheme with subgroup method

    International Nuclear Information System (INIS)

    Cao, L.; He, Q.; Wu, H.; Zu, T.; Shen, W.

    2015-01-01

    A fast Resonance Interference Factor (RIF) scheme is proposed to treat the resonance interference effects between different resonance nuclides. This scheme utilizes the conventional subgroup method to evaluate the self-shielded cross sections of the dominant resonance nuclide in the heterogeneous system and the hyper-fine energy group method to represent the resonance interference effects in a simplified homogeneous model. In this paper, the newly implemented scheme is compared to the background iteration scheme, the Resonance Nuclide Group (RNG) scheme and the conventional RIF scheme. The numerical results show that the errors of the effective self-shielded cross sections are significantly reduced by the fast RIF scheme compared with the background iteration scheme and the RNG scheme. Besides, the fast RIF scheme consumes less computation time than the conventional RIF schemes. The speed-up ratio is ~4.5 for MOX pin cell problems. (author)

  6. Arbitrated quantum signature scheme with message recovery

    International Nuclear Information System (INIS)

    Lee, Hwayean; Hong, Changho; Kim, Hyunsang; Lim, Jongin; Yang, Hyung Jin

    2004-01-01

    Two quantum signature schemes with message recovery relying on the availability of an arbitrator are proposed. One scheme uses a public board and the other does not. However both schemes provide confidentiality of the message and a higher efficiency in transmission

  7. CANONICAL BACKWARD DIFFERENTIATION SCHEMES FOR ...

    African Journals Online (AJOL)

    This paper describes a new nonlinear backward differentiation schemes for the numerical solution of nonlinear initial value problems of first order ordinary differential equations. The schemes are based on rational interpolation obtained from canonical polynomials. They are A-stable. The test problems show that they give ...

  8. A simple angular transmit diversity scheme using a single RF frontend for PSK modulation schemes

    DEFF Research Database (Denmark)

    Alrabadi, Osama Nafeth Saleem; Papadias, Constantinos B.; Kalis, Antonis

    2009-01-01

    array (SPA) with a single transceiver, and an array area of 0.0625 square wavelengths. The scheme which requires no channel state information (CSI) at the transmitter, provides mainly a diversity gain to combat against multipath fading. The performance/capacity of the proposed diversity scheme...

  9. Evaluating statistical cloud schemes

    OpenAIRE

    Grützun, Verena; Quaas, Johannes; Morcrette , Cyril J.; Ament, Felix

    2015-01-01

    Statistical cloud schemes with prognostic probability distribution functions have become more important in atmospheric modeling, especially since they are in principle scale adaptive and capture cloud physics in more detail. While in theory the schemes have a great potential, their accuracy is still questionable. High-resolution three-dimensional observational data of water vapor and cloud water, which could be used for testing them, are missing. We explore the potential of ground-based re...

  10. Comprehensive Benefit Evaluation of the Power Distribution Network Planning Project Based on Improved IAHP and Multi-Level Extension Assessment Method

    OpenAIRE

    Qunli Wu; Chenyang Peng

    2016-01-01

    Reasonable distribution network planning is an essential prerequisite of the economics and security of the future power grid. The comprehensive benefit evaluation of a distribution network planning project can make significant contributions towards guiding decisions during the planning scheme, the optimization of the distribution network structure, and the rational use of resources. In this paper, in light of the characteristics of the power distribution network, the comprehensive benefit eva...

  11. Casemix and rehabilitation: evaluation of an early discharge scheme.

    Science.gov (United States)

    Brandis, S

    2000-01-01

    This paper presents a case study of an early discharge scheme funded by casemix incentives and discusses limitations of a casemix model of funding whereby hospital inpatient care is funded separately from care in other settings. The POSITIVE Rehabilitation program received 151 patients discharged early from hospital in a twelve-month period. Program evaluation demonstrates a 40.9% drop in the average length of stay of rehabilitation patients and a 42.6% drop in average length of stay for patients with stroke. Other benefits of the program include a high level of patient satisfaction, improved carer support and increased continuity of care. The challenge under the Australian interpretation of a casemix model of funding is ensuring the viability of services that extend across acute hospital, non-acute care, and community and home settings.

  12. Static and dynamic efficiency of white certificate schemes; L'efficacite statique et dynamique des dispositifs de -certificats blancs-

    Energy Technology Data Exchange (ETDEWEB)

    Giraudet, L.G. [CIRED-ENPC, 94 - Nogent-sur-Marne (France); Finon, D. [CIRED-CNRS, 94 - Nogent-sur-Marne (France)

    2011-07-15

    White Certificate Schemes mandate energy companies to promote energy efficiency through flexibility mechanisms, including the trading of energy savings. They can be characterized as a quantity-based, baseline-and-credit system for the diffusion of energy efficient technologies. This paper compares experiences with White Certificate Schemes in Great Britain, Italy and France, in order to identify the basic drivers of each, and ultimately offer an original interpretation as an adaptive instrument, in the sense that it can take different forms in response to specific institutional contexts. A first analysis shows that Schemes perform well in terms of static efficiency, i.e. they are cost-effective and generate net social benefits over the period considered, though with large discrepancies rooted in different technological potentials. Regarding dynamic efficiency, i.e. the ability to induce and sustain technological change over the long haul, market transformation occurred in Great Britain, but was poorly incentivized in Italy and France by inadequate compliance cost recovery rules. Substantial organizational change has occurred in every country, mainly by strengthening vertical relationships between obliged parties and upstream businesses. Overall, the obligation (rather than the market component) drives the early phases of the Schemes. (authors)

  13. A scheme to promote the world's economic development with migration.

    Science.gov (United States)

    Simon, J L

    1982-01-01

    housing and amenities for the migrants and the kind of occupational training they would receive. Such a contract could be a profitable means of earning foreign currency for a country. Another side benefit of the scheme is its possible use as an anticyclical device. A difficult question is the lenght (or permanence) of migratory residents. Clearly, a migration scheme will be adopted in the near future, and if it can be implemented it might work wonders for the economic development of the world.

  14. LDPC-PPM Coding Scheme for Optical Communication

    Science.gov (United States)

    Barsoum, Maged; Moision, Bruce; Divsalar, Dariush; Fitz, Michael

    2009-01-01

    In a proposed coding-and-modulation/demodulation-and-decoding scheme for a free-space optical communication system, an error-correcting code of the low-density parity-check (LDPC) type would be concatenated with a modulation code that consists of a mapping of bits to pulse-position-modulation (PPM) symbols. Hence, the scheme is denoted LDPC-PPM. This scheme could be considered a competitor of a related prior scheme in which an outer convolutional error-correcting code is concatenated with an interleaving operation, a bit-accumulation operation, and a PPM inner code. Both the prior and present schemes can be characterized as serially concatenated pulse-position modulation (SCPPM) coding schemes. Figure 1 represents a free-space optical communication system based on either the present LDPC-PPM scheme or the prior SCPPM scheme. At the transmitting terminal, the original data (u) are processed by an encoder into blocks of bits (a), and the encoded data are mapped to PPM of an optical signal (c). For the purpose of design and analysis, the optical channel in which the PPM signal propagates is modeled as a Poisson point process. At the receiving terminal, the arriving optical signal (y) is demodulated to obtain an estimate (a^) of the coded data, which is then processed by a decoder to obtain an estimate (u^) of the original data.

  15. Preparation of PbS and PbO nanopowders from new Pb(II)(saccharine) coordination polymers

    International Nuclear Information System (INIS)

    Aslani, Alireza; Musevi, Seyid Javad; Şahin, Ertan; Yilmaz, Veysel T.

    2014-01-01

    Highlights: • The complex of compounds “[Pb(H 2 O)(μ-OAc)(μ-sac)] n ” are synthesized at nano and bulk size structurally diverse and show interesting three-dimensional coordination polymers. • Reduction of the particle size of the coordination polymers to a few dozen nanometers results in lower thermal stability when compared to the single crystalline samples. • This study demonstrates that the metal–organic framework may be suitable precursors for the preparation of nanoscale materials with interesting morphologies. - Abstract: Nanopowders and single crystal of new Pb(II) three-dimensional coordination polymer, [Pb(H 2 O)(μ-OAc)(μ-sac)] n “PASAC” were synthesized by a sonochemical and branched tube methods (Yılmaz et al., Z. Anorg. Allg. Chem. 629 (2003) 172). The new nano-structures of Pb(II) coordination polymer were characterized by X-ray crystallography analysis, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), surface analysis (BET), and IR spectroscopy. The crystal structure of these compounds consists of three-dimensional polymeric units. The thermal stability of compounds was studied by thermal gravimetric analysis (TGA) and differential thermal analyses (DTA). PbS and PbO nano-structures were obtained by calcinations of the nano-structures of this coordination polymer at 600 °C

  16. Multidimensional flux-limited advection schemes

    International Nuclear Information System (INIS)

    Thuburn, J.

    1996-01-01

    A general method for building multidimensional shape preserving advection schemes using flux limiters is presented. The method works for advected passive scalars in either compressible or incompressible flow and on arbitrary grids. With a minor modification it can be applied to the equation for fluid density. Schemes using the simplest form of the flux limiter can cause distortion of the advected profile, particularly sideways spreading, depending on the orientation of the flow relative to the grid. This is partly because the simple limiter is too restrictive. However, some straightforward refinements lead to a shape-preserving scheme that gives satisfactory results, with negligible grid-flow angle-dependent distortion

  17. Carbon righteousness: how to lever pro-poor benefits from REDD+

    Energy Technology Data Exchange (ETDEWEB)

    Scwarte, Christoph [Foundation for International Environmental Law and Development(United Kingdom); Mohammed, Essam Yassin

    2011-07-15

    A growing focus on mitigating climate change by reducing emissions from deforestation and forest degradation (REDD and REDD+) is prompting the creation of a new form of private property — the 'carbon right' — that can be bought and sold in domestic or international markets. But to make REDD+ work for the poor, carbon trading schemes will have to ensure that a wide range of forest-dependent groups and communities benefit. In part, this means carefully assessing how carbon rights are assigned — to ensure they support the rural poor who rarely hold formal land ownership or tenure rights but who are key players in putting sustainable forest management into practice on the ground. It also means rethinking eligibility criteria for REDD+ projects so that they include economic, social and environmental standards and co-benefits.

  18. Addressing healthcare needs of people living below the poverty line: a rapid assessment of the Andhra Pradesh Health Insurance Scheme.

    Science.gov (United States)

    Rao, M; Ramachandra, S S; Bandyopadhyay, S; Chandran, A; Shidhaye, R; Tamisettynarayana, S; Thippaiah, A; Sitamma, M; Sunil George, M; Singh, V; Sivasankaran, S; Bangdiwala, S I

    2011-01-01

    Families living below the poverty line in countries which do not have universal healthcare coverage are drawn into indebtedness and bankruptcy. The state of Andhra Pradesh in India established the Rajiv Aarogyasri Community Health Insurance Scheme (RACHIS) in 2007 with the aim of breaking this cycle by improving the access of below the poverty line (BPL) families to secondary and tertiary healthcare. It covered a wide range of surgical and medical treatments for serious illnesses requiring specialist healthcare resources not always available at district-level government hospitals. The impact of this scheme was evaluated by a rapid assessment, commissioned by the government of Andhra Pradesh. The aim of the assessment was to explore the contribution of the scheme to the reduction of catastrophic health expenditure among the poor and to recommend ways by which delivery of the scheme could be improved. We report the findings of this assessment. Two types of data were used for the assessment. Patient data pertaining to 89 699 treatment requests approved by the scheme during its first 18 months were examined. Second, surveys of scheme beneficiaries and providers were undertaken in 6 randomly selected districts of Andhra Pradesh. This novel scheme was beginning to reach the BPL households in the state and providing access to free secondary and tertiary healthcare to seriously ill poor people. An integrated model encompassing primary, secondary and tertiary care would be of greater benefit to families below the poverty line and more cost-effective for the government. There is considerable potential for the government to build on this successful start and to strengthen equity of access and the quality of care provided by the scheme. Copyright 2011, NMJI.

  19. Tightly Secure Signatures From Lossy Identification Schemes

    OpenAIRE

    Abdalla , Michel; Fouque , Pierre-Alain; Lyubashevsky , Vadim; Tibouchi , Mehdi

    2015-01-01

    International audience; In this paper, we present three digital signature schemes with tight security reductions in the random oracle model. Our first signature scheme is a particularly efficient version of the short exponent discrete log-based scheme of Girault et al. (J Cryptol 19(4):463–487, 2006). Our scheme has a tight reduction to the decisional short discrete logarithm problem, while still maintaining the non-tight reduction to the computational version of the problem upon which the or...

  20. An Electron Bunch Compression Scheme for a Superconducting Radio Frequency Linear Accelerator Driven Light Source

    Energy Technology Data Exchange (ETDEWEB)

    C. Tennant, S.V. Benson, D. Douglas, P. Evtushenko, R.A. Legg

    2011-09-01

    We describe an electron bunch compression scheme suitable for use in a light source driven by a superconducting radio frequency (SRF) linac. The key feature is the use of a recirculating linac to perform the initial bunch compression. Phasing of the second pass beam through the linac is chosen to de-chirp the electron bunch prior to acceleration to the final energy in an SRF linac ('afterburner'). The final bunch compression is then done at maximum energy. This scheme has the potential to circumvent some of the most technically challenging aspects of current longitudinal matches; namely transporting a fully compressed, high peak current electron bunch through an extended SRF environment, the need for a RF harmonic linearizer and the need for a laser heater. Additional benefits include a substantial savings in capital and operational costs by efficiently using the available SRF gradient.

  1. Assessing the changes of groundwater recharge / irrigation water use between SRI and traditional irrigation schemes in Central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2015-04-01

    To respond to agricultural water shortage impacted by climate change without affecting rice yield in the future, the application of water-saving irrigation, such as SRI methodology, is considered to be adopted in rice-cultivation in Taiwan. However, the flooded paddy fields could be considered as an important source of groundwater recharge in Central Taiwan. The water-saving benefit of this new methodology and its impact on the reducing of groundwater recharge should be integrally assessed in this area. The objective of this study was to evaluate the changes of groundwater recharge/ irrigation water use between the SRI and traditional irrigation schemes (continuous irrigation, rotational irrigation). An experimental paddy field located in the proximal area of the Choushui River alluvial fan (the largest groundwater pumping region in Taiwan) was chosen as the study area. The 3-D finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge process and amount under traditional irrigation schemes and SRI methodology. The use of effective rainfall was taken into account or not in different simulation scenarios for each irrigation scheme. The simulation results showed that there were no significant variations of infiltration rate in the use of effective rainfall or not, but the low soil moisture setting in deep soil layers resulted in higher infiltration rate. Taking the use of effective rainfall into account, the average infiltration rate for continuous irrigation, rotational irrigation, and SRI methodology in the first crop season of 2013 were 4.04 mm/day, 4.00 mm/day and 3.92 mm/day, respectively. The groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reducing 4% and 2% compared with continuous irrigation and rotational irrigation, respectively. The field irrigation requirement amount of SRI methodology was significantly

  2. Scheme of energy utilities

    International Nuclear Information System (INIS)

    2002-04-01

    This scheme defines the objectives relative to the renewable energies and the rational use of the energy in the framework of the national energy policy. It evaluates the needs and the potentialities of the regions and preconizes the actions between the government and the territorial organizations. The document is presented in four parts: the situation, the stakes and forecasts; the possible actions for new measures; the scheme management and the regional contributions analysis. (A.L.B.)

  3. Error forecasting schemes of error correction at receiver

    International Nuclear Information System (INIS)

    Bhunia, C.T.

    2007-08-01

    To combat error in computer communication networks, ARQ (Automatic Repeat Request) techniques are used. Recently Chakraborty has proposed a simple technique called the packet combining scheme in which error is corrected at the receiver from the erroneous copies. Packet Combining (PC) scheme fails: (i) when bit error locations in erroneous copies are the same and (ii) when multiple bit errors occur. Both these have been addressed recently by two schemes known as Packet Reversed Packet Combining (PRPC) Scheme, and Modified Packet Combining (MPC) Scheme respectively. In the letter, two error forecasting correction schemes are reported, which in combination with PRPC offer higher throughput. (author)

  4. Biophysical modeling of in vitro and in vivo processes underlying regulated photoprotective mechanism in cyanobacteria.

    Science.gov (United States)

    Shirshin, Evgeny A; Nikonova, Elena E; Kuzminov, Fedor I; Sluchanko, Nikolai N; Elanskaya, Irina V; Gorbunov, Maxim Y; Fadeev, Victor V; Friedrich, Thomas; Maksimov, Eugene G

    2017-09-01

    Non-photochemical quenching (NPQ) is a mechanism responsible for high light tolerance in photosynthetic organisms. In cyanobacteria, NPQ is realized by the interplay between light-harvesting complexes, phycobilisomes (PBs), a light sensor and effector of NPQ, the photoactive orange carotenoid protein (OCP), and the fluorescence recovery protein (FRP). Here, we introduced a biophysical model, which takes into account the whole spectrum of interactions between PBs, OCP, and FRP and describes the experimental PBs fluorescence kinetics, unraveling interaction rate constants between the components involved and their relative concentrations in the cell. We took benefit from the possibility to reconstruct the photoprotection mechanism and its parts in vitro, where most of the parameters could be varied, to develop the model and then applied it to describe the NPQ kinetics in the Synechocystis sp. PCC 6803 mutant lacking photosystems. Our analyses revealed  that while an excess of the OCP over PBs is required to obtain substantial PBs fluorescence quenching in vitro, in vivo the OCP/PBs ratio is less than unity, due to higher local concentration of PBs, which was estimated as ~10 -5 M, compared to in vitro experiments. The analysis of PBs fluorescence recovery on the basis of the generalized model of enzymatic catalysis resulted in determination of the FRP concentration in vivo close to 10% of the OCP concentration. Finally, the possible role of the FRP oligomeric state alteration in the kinetics of PBs fluorescence was shown. This paper provides the most comprehensive model of the OCP-induced PBs fluorescence quenching to date and the results are important for better understanding of the regulatory molecular mechanisms underlying NPQ in cyanobacteria.

  5. A critical discussion of the benefits of e-health in population-level dental research.

    Science.gov (United States)

    Lam, Raymond; Kruger, Estie; Tennant, Marc

    2013-01-01

    Population-level research is an essential area of health with the potential to affect quality of life and the broader economy. There are excellent epidemiological studies that have improved health services, but traditional research requires a considerable investment. Although electronic technology has changed the practice of many industries with improved efficiency, its application to health is relatively new. Termed 'e-health', this emerging area has been defined by the World Health Organization as the use of information technology to support many aspects of health such as in administration and scientific information. However, not all professionals are convinced of its use. This paper presents a novel application of this emerging area to describe the benefit in data collation and research to support one of the most pressing issues in public health: oral health and policy. Using the Chronic Disease Dental Scheme as an example, a critical discussion of its benefit to population-level research is presented. The Chronic Disease Dental Scheme method of electronic administration has been shown to enhance research and to complement existing progress in health data linkage. e-Health is an invaluable tool for population-level dental research.

  6. Estimating plume dispersion: a comparison of several sigma schemes

    International Nuclear Information System (INIS)

    Irwin, J.S.

    1983-01-01

    The lateral and vertical Gaussian plume dispersion parameters are estimated and compared with field tracer data collected at 11 sites. The dispersion parameter schemes used in this analysis include Cramer's scheme, suggested for tall stack dispersion estimates, Draxler's scheme, suggested for elevated and surface releases, Pasquill's scheme, suggested for interim use in dispersion estimates, and the Pasquill--Gifford scheme using Turner's technique for assigning stability categories. The schemes suggested by Cramer, Draxler and Pasquill estimate the dispersion parameters using onsite measurements of the vertical and lateral wind-velocity variances at the effective release height. The performances of these schemes in estimating the dispersion parameters are compared with that of the Pasquill--Gifford scheme, using the Prairie Grass and Karlsruhe data. For these two experiments, the estimates of the dispersion parameters using Draxler's scheme correlate better with the measurements than did estimates using the Pasquill--Gifford scheme. Comparison of the dispersion parameter estimates with the measurement suggests that Draxler's scheme for characterizing the dispersion results in the smallest mean fractional error in the estimated dispersion parameters and the smallest variance of the fractional errors

  7. Health and climate benefits of cookstove replacement options

    International Nuclear Information System (INIS)

    Grieshop, Andrew P.; Marshall, Julian D.; Kandlikar, Milind

    2011-01-01

    The health and climate impacts of available household cooking options in developing countries vary sharply. Here, we analyze and compare these impacts (health; climate) and the potential co-benefits from the use of fuel and stove combinations. Our results indicate that health and climate impacts span 2 orders of magnitude among the technologies considered. Indoor air pollution is heavily impacted by combustion performance and ventilation; climate impacts are influenced by combustion performance and fuel properties including biomass renewability. Emission components not included in current carbon trading schemes, such as black carbon particles and carbon monoxide, can contribute a large proportion of the total climate impact. Multiple ‘improved’ stove options analyzed in this paper yield roughly equivalent climate benefits but have different impacts on indoor air pollution. Improvements to biomass stoves can improve indoor air quality, which nonetheless remains significantly higher than for stoves that use liquid or gaseous hydrocarbons. LPG- and kerosene-fueled stoves have unrivaled air quality benefits and their climate impacts are also lower than all but the cleanest stoves using renewable biomass. - Research highlights: ► Cookstoves in developing countries have impacts on users' health and the climate. ► A framework to estimate these impacts from different stove types was developed.► Much of stoves' climate impacts are from emissions excluded from climate treaties.► Improved stoves rank differently in their climate and health impacts.► Stoves using modern fuels like LPG provide unrivaled exposure and climate benefits.

  8. Resonance ionization scheme development for europium

    Energy Technology Data Exchange (ETDEWEB)

    Chrysalidis, K., E-mail: katerina.chrysalidis@cern.ch; Goodacre, T. Day; Fedosseev, V. N.; Marsh, B. A. [CERN (Switzerland); Naubereit, P. [Johannes Gutenberg-Universität, Institiut für Physik (Germany); Rothe, S.; Seiffert, C. [CERN (Switzerland); Kron, T.; Wendt, K. [Johannes Gutenberg-Universität, Institiut für Physik (Germany)

    2017-11-15

    Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionization schemes are proposed. The scheme development was the first application of the Photo Ionization Spectroscopy Apparatus (PISA) which has recently been integrated into the RILIS setup.

  9. Secure RAID Schemes for Distributed Storage

    OpenAIRE

    Huang, Wentao; Bruck, Jehoshua

    2016-01-01

    We propose secure RAID, i.e., low-complexity schemes to store information in a distributed manner that is resilient to node failures and resistant to node eavesdropping. We generalize the concept of systematic encoding to secure RAID and show that systematic schemes have significant advantages in the efficiencies of encoding, decoding and random access. For the practical high rate regime, we construct three XOR-based systematic secure RAID schemes with optimal or almost optimal encoding and ...

  10. Wireless Broadband Access and Accounting Schemes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In this paper, we propose two wireless broadband access and accounting schemes. In both schemes, the accounting system adopts RADIUS protocol, but the access system adopts SSH and SSL protocols respectively.

  11. Security analysis and improvements of arbitrated quantum signature schemes

    International Nuclear Information System (INIS)

    Zou Xiangfu; Qiu Daowen

    2010-01-01

    A digital signature is a mathematical scheme for demonstrating the authenticity of a digital message or document. For signing quantum messages, some arbitrated quantum signature (AQS) schemes have been proposed. It was claimed that these AQS schemes could guarantee unconditional security. However, we show that they can be repudiated by the receiver Bob. To conquer this shortcoming, we construct an AQS scheme using a public board. The AQS scheme not only avoids being disavowed by the receiver but also preserves all merits in the existing schemes. Furthermore, we discover that entanglement is not necessary while all these existing AQS schemes depend on entanglement. Therefore, we present another AQS scheme without utilizing entangled states in the signing phase and the verifying phase. This scheme has three advantages: it does not utilize entangled states and it preserves all merits in the existing schemes; the signature can avoid being disavowed by the receiver; and it provides a higher efficiency in transmission and reduces the complexity of implementation.

  12. Evaluation of Closed Adult Nucleus Multiple Ovulation and Embryo Transfer and Conventional Progeny Testing Breeding Schemes for Milk Production from Crossbred Cattle in the Tropics

    NARCIS (Netherlands)

    Kosgey, I.S.; Kahi, A.K.; Arendonk, van J.A.M.

    2005-01-01

    The potential benefits of closed adult nucleus multiple ovulation and embryo transfer (MOET) and conventional progeny testing (CNS) schemes, and the logistics of their integration into large-scale continuous production of crossbred cattle were studied by deterministic simulation. The latter was

  13. Capacity-achieving CPM schemes

    OpenAIRE

    Perotti, Alberto; Tarable, Alberto; Benedetto, Sergio; Montorsi, Guido

    2008-01-01

    The pragmatic approach to coded continuous-phase modulation (CPM) is proposed as a capacity-achieving low-complexity alternative to the serially-concatenated CPM (SC-CPM) coding scheme. In this paper, we first perform a selection of the best spectrally-efficient CPM modulations to be embedded into SC-CPM schemes. Then, we consider the pragmatic capacity (a.k.a. BICM capacity) of CPM modulations and optimize it through a careful design of the mapping between input bits and CPM waveforms. The s...

  14. Improvement of a Quantum Proxy Blind Signature Scheme

    Science.gov (United States)

    Zhang, Jia-Lei; Zhang, Jian-Zhong; Xie, Shu-Cui

    2018-06-01

    Improvement of a quantum proxy blind signature scheme is proposed in this paper. Six-qubit entangled state functions as quantum channel. In our scheme, a trust party Trent is introduced so as to avoid David's dishonest behavior. The receiver David verifies the signature with the help of Trent in our scheme. The scheme uses the physical characteristics of quantum mechanics to implement message blinding, delegation, signature and verification. Security analysis proves that our scheme has the properties of undeniability, unforgeability, anonymity and can resist some common attacks.

  15. A group signature scheme based on quantum teleportation

    International Nuclear Information System (INIS)

    Wen Xiaojun; Tian Yuan; Ji Liping; Niu Xiamu

    2010-01-01

    In this paper, we present a group signature scheme using quantum teleportation. Different from classical group signature and current quantum signature schemes, which could only deliver either group signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Security analysis proved that our scheme has the characteristics of group signature, non-counterfeit, non-disavowal, blindness and traceability. Our quantum group signature scheme has a foreseeable application in the e-payment system, e-government, e-business, etc.

  16. A group signature scheme based on quantum teleportation

    Energy Technology Data Exchange (ETDEWEB)

    Wen Xiaojun; Tian Yuan; Ji Liping; Niu Xiamu, E-mail: wxjun36@gmail.co [Information Countermeasure Technique Research Institute, Harbin Institute of Technology, Harbin 150001 (China)

    2010-05-01

    In this paper, we present a group signature scheme using quantum teleportation. Different from classical group signature and current quantum signature schemes, which could only deliver either group signature or unconditional security, our scheme guarantees both by adopting quantum key preparation, quantum encryption algorithm and quantum teleportation. Security analysis proved that our scheme has the characteristics of group signature, non-counterfeit, non-disavowal, blindness and traceability. Our quantum group signature scheme has a foreseeable application in the e-payment system, e-government, e-business, etc.

  17. A new access scheme in OFDMA systems

    Institute of Scientific and Technical Information of China (English)

    GU Xue-lin; YAN Wei; TIAN Hui; ZHANG Ping

    2006-01-01

    This article presents a dynamic random access scheme for orthogonal frequency division multiple access (OFDMA) systems. The key features of the proposed scheme are:it is a combination of both the distributed and the centralized schemes, it can accommodate several delay sensitivity classes,and it can adjust the number of random access channels in a media access control (MAC) frame and the access probability according to the outcome of Mobile Terminals access attempts in previous MAC frames. For floating populated packet-based networks, the proposed scheme possibly leads to high average user satisfaction.

  18. Adaptive transmission schemes for MISO spectrum sharing systems

    KAUST Repository

    Bouida, Zied

    2013-06-01

    We propose three adaptive transmission techniques aiming to maximize the capacity of a multiple-input-single-output (MISO) secondary system under the scenario of an underlay cognitive radio network. In the first scheme, namely the best antenna selection (BAS) scheme, the antenna maximizing the capacity of the secondary link is used for transmission. We then propose an orthogonal space time bloc code (OSTBC) transmission scheme using the Alamouti scheme with transmit antenna selection (TAS), namely the TAS/STBC scheme. The performance improvement offered by this scheme comes at the expense of an increased complexity and delay when compared to the BAS scheme. As a compromise between these schemes, we propose a hybrid scheme using BAS when only one antenna verifies the interference condition and TAS/STBC when two or more antennas are illegible for communication. We first derive closed-form expressions of the statistics of the received signal-to-interference-and-noise ratio (SINR) at the secondary receiver (SR). These results are then used to analyze the performance of the proposed techniques in terms of the average spectral efficiency, the average number of transmit antennas, and the average bit error rate (BER). This performance is then illustrated via selected numerical examples. © 2013 IEEE.

  19. Scheme-Independent Predictions in QCD: Commensurate Scale Relations and Physical Renormalization Schemes

    International Nuclear Information System (INIS)

    Brodsky, Stanley J.

    1998-01-01

    Commensurate scale relations are perturbative QCD predictions which relate observable to observable at fixed relative scale, such as the ''generalized Crewther relation'', which connects the Bjorken and Gross-Llewellyn Smith deep inelastic scattering sum rules to measurements of the e + e - annihilation cross section. All non-conformal effects are absorbed by fixing the ratio of the respective momentum transfer and energy scales. In the case of fixed-point theories, commensurate scale relations relate both the ratio of couplings and the ratio of scales as the fixed point is approached. The relations between the observables are independent of the choice of intermediate renormalization scheme or other theoretical conventions. Commensurate scale relations also provide an extension of the standard minimal subtraction scheme, which is analytic in the quark masses, has non-ambiguous scale-setting properties, and inherits the physical properties of the effective charge α V (Q 2 ) defined from the heavy quark potential. The application of the analytic scheme to the calculation of quark-mass-dependent QCD corrections to the Z width is also reviewed

  20. Quantum attack-resistent certificateless multi-receiver signcryption scheme.

    Directory of Open Access Journals (Sweden)

    Huixian Li

    Full Text Available The existing certificateless signcryption schemes were designed mainly based on the traditional public key cryptography, in which the security relies on the hard problems, such as factor decomposition and discrete logarithm. However, these problems will be easily solved by the quantum computing. So the existing certificateless signcryption schemes are vulnerable to the quantum attack. Multivariate public key cryptography (MPKC, which can resist the quantum attack, is one of the alternative solutions to guarantee the security of communications in the post-quantum age. Motivated by these concerns, we proposed a new construction of the certificateless multi-receiver signcryption scheme (CLMSC based on MPKC. The new scheme inherits the security of MPKC, which can withstand the quantum attack. Multivariate quadratic polynomial operations, which have lower computation complexity than bilinear pairing operations, are employed in signcrypting a message for a certain number of receivers in our scheme. Security analysis shows that our scheme is a secure MPKC-based scheme. We proved its security under the hardness of the Multivariate Quadratic (MQ problem and its unforgeability under the Isomorphism of Polynomials (IP assumption in the random oracle model. The analysis results show that our scheme also has the security properties of non-repudiation, perfect forward secrecy, perfect backward secrecy and public verifiability. Compared with the existing schemes in terms of computation complexity and ciphertext length, our scheme is more efficient, which makes it suitable for terminals with low computation capacity like smart cards.

  1. Does insurance enrolment increase healthcare utilisation among rural-dwelling older adults? Evidence from the National Health Insurance Scheme in Ghana.

    Science.gov (United States)

    van der Wielen, Nele; Channon, Andrew Amos; Falkingham, Jane

    2018-01-01

    This paper examines the relationship between national health insurance enrolment and the utilisation of inpatient and outpatient healthcare for older adults in rural areas in Ghana. The Ghanaian National Health Insurance Scheme (NHIS) aims to improve affordability and increase the utilisation of healthcare. However, the system has been criticised for not being responsive to the needs of older adults. The majority of older adults in Ghana live in rural areas with poor accessibility to healthcare. With an ageing population, a specific assessment of whether the scheme has benefitted older adults, and also if the benefit is equitable, is needed. Using the Ghanaian Living Standards Survey from 2012 to 2013, this paper uses propensity score matching to estimate the effect of enrolment within the NHIS on the utilisation of inpatient and outpatient care among older people aged 50 and over. The raw results show higher utilisation of healthcare among NHIS members, which persists after matching. NHIS members were 6% and 9% more likely to use inpatient and outpatient care, respectively, than non-members. When these increases were disaggregated for outpatient care, the non-poor and females were seen to benefit more than their poor and male counterparts. For inpatient care, the benefits of enrolment were equal by poverty status and sex. However, overall, poor older adults use health services much less than the non-poor older adults even when enrolled. The results indicate that NHIS coverage does increase healthcare utilisation among rural older adults but that inequalities remain. The poor are still at a great disadvantage in their use of health services overall and benefit less from enrolment for outpatient care. The receipt of healthcare is significantly influenced by a set of auxiliary barriers to access to healthcare even where insurance should remove the financial burden of ad hoc out of pocket payments.

  2. Birkhoffian Symplectic Scheme for a Quantum System

    International Nuclear Information System (INIS)

    Su Hongling

    2010-01-01

    In this paper, a classical system of ordinary differential equations is built to describe a kind of n-dimensional quantum systems. The absorption spectrum and the density of the states for the system are defined from the points of quantum view and classical view. From the Birkhoffian form of the equations, a Birkhoffian symplectic scheme is derived for solving n-dimensional equations by using the generating function method. Besides the Birkhoffian structure-preserving, the new scheme is proven to preserve the discrete local energy conservation law of the system with zero vector f. Some numerical experiments for a 3-dimensional example show that the new scheme can simulate the general Birkhoffian system better than the implicit midpoint scheme, which is well known to be symplectic scheme for Hamiltonian system. (general)

  3. Autonomous droop scheme with reduced generation cost

    DEFF Research Database (Denmark)

    Nutkani, Inam Ullah; Loh, Poh Chiang; Blaabjerg, Frede

    2013-01-01

    Droop scheme has been widely applied to the control of Distributed Generators (DGs) in microgrids for proportional power sharing based on their ratings. For standalone microgrid, where centralized management system is not viable, the proportional power sharing based droop might not suit well since...... DGs are usually of different types unlike synchronous generators. This paper presents an autonomous droop scheme that takes into consideration the operating cost, efficiency and emission penalty of each DG since all these factors directly or indirectly contributes to the Total Generation Cost (TGC......) of the overall microgrid. Comparing it with the traditional scheme, the proposed scheme has retained its simplicity, which certainly is a feature preferred by the industry. The overall performance of the proposed scheme has been verified through simulation and experiment....

  4. Enhanced arbitrated quantum signature scheme using Bell states

    International Nuclear Information System (INIS)

    Wang Chao; Liu Jian-Wei; Shang Tao

    2014-01-01

    We investigate the existing arbitrated quantum signature schemes as well as their cryptanalysis, including intercept-resend attack and denial-of-service attack. By exploring the loopholes of these schemes, a malicious signatory may successfully disavow signed messages, or the receiver may actively negate the signature from the signatory without being detected. By modifying the existing schemes, we develop counter-measures to these attacks using Bell states. The newly proposed scheme puts forward the security of arbitrated quantum signature. Furthermore, several valuable topics are also presented for further research of the quantum signature scheme

  5. Decoupling schemes for the SSC Collider

    International Nuclear Information System (INIS)

    Cai, Y.; Bourianoff, G.; Cole, B.; Meinke, R.; Peterson, J.; Pilat, F.; Stampke, S.; Syphers, M.; Talman, R.

    1993-05-01

    A decoupling system is designed for the SSC Collider. This system can accommodate three decoupling schemes by using 44 skew quadrupoles in the different configurations. Several decoupling schemes are studied and compared in this paper

  6. Time-and-ID-Based Proxy Reencryption Scheme

    Directory of Open Access Journals (Sweden)

    Kambombo Mtonga

    2014-01-01

    Full Text Available Time- and ID-based proxy reencryption scheme is proposed in this paper in which a type-based proxy reencryption enables the delegator to implement fine-grained policies with one key pair without any additional trust on the proxy. However, in some applications, the time within which the data was sampled or collected is very critical. In such applications, for example, healthcare and criminal investigations, the delegatee may be interested in only some of the messages with some types sampled within some time bound instead of the entire subset. Hence, in order to carter for such situations, in this paper, we propose a time-and-identity-based proxy reencryption scheme that takes into account the time within which the data was collected as a factor to consider when categorizing data in addition to its type. Our scheme is based on Boneh and Boyen identity-based scheme (BB-IBE and Matsuo’s proxy reencryption scheme for identity-based encryption (IBE to IBE. We prove that our scheme is semantically secure in the standard model.

  7. Cancelable remote quantum fingerprint templates protection scheme

    International Nuclear Information System (INIS)

    Liao Qin; Guo Ying; Huang Duan

    2017-01-01

    With the increasing popularity of fingerprint identification technology, its security and privacy have been paid much attention. Only the security and privacy of biological information are insured, the biological technology can be better accepted and used by the public. In this paper, we propose a novel quantum bit (qbit)-based scheme to solve the security and privacy problem existing in the traditional fingerprint identification system. By exploiting the properties of quantm mechanics, our proposed scheme, cancelable remote quantum fingerprint templates protection scheme, can achieve the unconditional security guaranteed in an information-theoretical sense. Moreover, this novel quantum scheme can invalidate most of the attacks aimed at the fingerprint identification system. In addition, the proposed scheme is applicable to the requirement of remote communication with no need to worry about its security and privacy during the transmission. This is an absolute advantage when comparing with other traditional methods. Security analysis shows that the proposed scheme can effectively ensure the communication security and the privacy of users’ information for the fingerprint identification. (paper)

  8. Energy supplier obligations and white certificate schemes: Comparative analysis of experiences in the European Union

    Energy Technology Data Exchange (ETDEWEB)

    Bertoldi, Paolo, E-mail: paolo.bertoldi@ec.europa.e [European Commission, Joint Research Centre, Institute for Energy, Via E. Fermi 1, TP 450, 21027 Ispra (Vatican City State, Holy See) (Italy); Rezessy, Silvia, E-mail: silvia.rezessy@ec.europa.e [European Commission, Joint Research Centre, Institute for Energy, Via E. Fermi 1, TP 450, 21027 Ispra (Vatican City State, Holy See) (Italy); Lees, Eoin, E-mail: eoin@eoinleesenergy.co [Eoin Lees Energy, 4 Silver Lane, West Challow, Wantage, Oxon OX12 9TX (United Kingdom); Baudry, Paul, E-mail: paul.baudry@edf.f [EDF R and D, Centre des Renardieres, 77818 Moret sur Loing (France); Jeandel, Alexandre, E-mail: alexandre.jeandel@gdfsuez.co [GDF SUEZ, 16, rue Ville L' Eveque, 75008 Paris (France); Labanca, Nicola, E-mail: nicola.labanca@polimi.i [eERG, Politecnico di Milano, Via Lambruschini n. 4, 20156 Milano (Italy)

    2010-03-15

    A number of Member States of the European Union (EU) have introduced market-based policy portfolios based on quantified energy savings obligations on energy distributors or suppliers, possibly coupled with certification of project-based energy savings (via white certificates), and the option to trade the certificates or obligations. The paper provides an up-to-date review and analysis of results to date of white certificate schemes in the EU. In the EU supplier obligations and white certificate schemes have delivered larger savings than originally expected with obliged companies exceeding targets and, in some cases, at cost below what policy makers have anticipated. Supplier obligations foster the uptake of standardised energy efficiency actions often targeting smaller energy users (residential sector), lowering the transaction costs and contributing to market transformation. The role of certificate trading is more ambiguous. Trading can bring benefits where the target is set sufficiently high with respect to the energy-saving potential in the sectors covered. Theoretically trading may be better suited for broader systems with comprehensive coverage, but even in smaller schemes trading may reduce the transaction costs of compliance for obliged actors without sufficient expertise on end-use energy efficiency. Yet, trading increases the administrative cost ratio of energy-saving obligations.

  9. Is MGNREG Scheme complementary to fishing activities? A study on some selected states of India

    Directory of Open Access Journals (Sweden)

    Chiranjib Neogi

    2016-01-01

    Full Text Available Freshwater fish output is taken as a proxy variable for empirical assessment of indirect benefits in terms of enhanced quantity of freshwater fish (output cultivation. It is not unlikely to assess empirically the productivity of subsidized public scheme when rural development or rural asset generations are underlined in the said scheme, MGNREG Act, 2005. Rainwater harvesting is a major component part of the scheme since about 49.5 per cent of the total fund is already utilized on water conservation and obviously it has an impact on the cultivation of freshwater fish output. Time series data on annual expenditure on MGNREG and corresponding freshwater fish output at the state level are taken during the period 2006-07 to 2013-14 for 16 major Indian states. Fixed effect model and random effect models are being applied and the Hausman specification test suggests that fixed effect model is more appropriate than random effect model. Significant differences among the intercepts of the selected states are revealed as per F test. The results of fixed effect panel regression establish that fish output is enhanced by 0.000257 thousand tones or 0.26 tones if MGNREG expenditure rises by one crore or 10 million rupees.

  10. Energy supplier obligations and white certificate schemes: Comparative analysis of experiences in the European Union

    International Nuclear Information System (INIS)

    Bertoldi, Paolo; Rezessy, Silvia; Lees, Eoin; Baudry, Paul; Jeandel, Alexandre; Labanca, Nicola

    2010-01-01

    A number of Member States of the European Union (EU) have introduced market-based policy portfolios based on quantified energy savings obligations on energy distributors or suppliers, possibly coupled with certification of project-based energy savings (via white certificates), and the option to trade the certificates or obligations. The paper provides an up-to-date review and analysis of results to date of white certificate schemes in the EU. In the EU supplier obligations and white certificate schemes have delivered larger savings than originally expected with obliged companies exceeding targets and, in some cases, at cost below what policy makers have anticipated. Supplier obligations foster the uptake of standardised energy efficiency actions often targeting smaller energy users (residential sector), lowering the transaction costs and contributing to market transformation. The role of certificate trading is more ambiguous. Trading can bring benefits where the target is set sufficiently high with respect to the energy-saving potential in the sectors covered. Theoretically trading may be better suited for broader systems with comprehensive coverage, but even in smaller schemes trading may reduce the transaction costs of compliance for obliged actors without sufficient expertise on end-use energy efficiency. Yet, trading increases the administrative cost ratio of energy-saving obligations.

  11. Outcome-based health equity across different social health insurance schemes for the elderly in China.

    Science.gov (United States)

    Liu, Xiaoting; Wong, Hung; Liu, Kai

    2016-01-14

    status. The results indicate that fragmented health insurance schemes generate inequitable health care utilization and health outcomes for the elderly. This study re-emphasizes the importance of reforming health insurance systems based on their health outcome rather than entitlement, which will particularly benefit the most vulnerable older groups.

  12. Integrated North Sea grids: The costs, the benefits and their distribution between countries

    International Nuclear Information System (INIS)

    Konstantelos, Ioannis; Pudjianto, Danny; Strbac, Goran; De Decker, Jan; Joseph, Pieter; Flament, Aurore; Kreutzkamp, Paul; Genoese, Fabio; Rehfeldt, Leif; Wallasch, Anna-Kathrin; Gerdes, Gerhard; Jafar, Muhammad; Yang, Yongtao; Tidemand, Nicolaj; Jansen, Jaap; Nieuwenhout, Frans; Welle, Adriaan van der; Veum, Karina

    2017-01-01

    A large number of offshore wind farms and interconnectors are expected to be constructed in the North Sea region over the coming decades, creating substantial opportunities for the deployment of integrated network solutions. Creating interconnected offshore grids that combine cross-border links and connections of offshore plants to shore offers multiple economic and environmental advantages for Europe's energy system. However, despite evidence that integrated solutions can be more beneficial than traditional radial connection practices, no such projects have been deployed yet. In this paper we quantify costs and benefits of integrated projects and investigate to which extent the cost-benefit sharing mechanism between participating countries can impede or encourage the development of integrated projects. Three concrete interconnection case studies in the North Sea area are analysed in detail using a national-level power system model. Model outputs are used to compute the net benefit of all involved stakeholders under different allocation schemes. Given the asymmetric distribution of costs and benefits, we recommend to consistently apply the Positive Net Benefit Differential mechanism as a starting point for negotiations on the financial closure of investments in integrated offshore infrastructure. - Highlights: • Three North Sea offshore gird case studies are analysed. • They are shown to have substantial net benefit over non-integrated network designs. • Asymmetric net benefit sharing between countries is shown to be a barrier. • Positive Net Benefit Differential method alleviates asymmetric benefits.

  13. The effect of anterior proton beams in the setting of a prostate-rectum spacer

    Energy Technology Data Exchange (ETDEWEB)

    Christodouleas, John P., E-mail: christojo@uphs.upenn.edu [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Tang, Shikui [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); Susil, Robert C.; McNutt, Todd R.; Song, Danny Y. [Department of Radiation Oncology and Radiation Molecular Sciences, Johns Hopkins Hospital, Baltimore, MD (United States); Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States); DeWeese, Theodore L. [Department of Radiation Oncology and Radiation Molecular Sciences, Johns Hopkins Hospital, Baltimore, MD (United States); Lu, Hsiao-Ming [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Both, Stefan [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, PA (United States)

    2013-10-01

    Studies suggest that anterior beams with in vivo range verification would improve rectal dosimetry in proton therapy for prostate cancer. We investigated whether prostate-rectum spacers would enhance or diminish the benefits of anterior proton beams in these treatments. Twenty milliliters of hydrogel was injected between the prostate and rectum of a cadaver using a transperineal approach. Computed tomography (CT) and magnetic resonance (MR) images were used to generate 7 uniform scanning (US) and 7 single-field uniform dose pencil-beam scanning (PBS) plans with different beam arrangements. Pearson correlations were calculated between rectal, bladder, and femoral head dosimetric outcomes and beam arrangement anterior scores, which characterize the degree to which dose is delivered anteriorly. The overall quality of each plan was compared using a virtual dose-escalation study. For US plans, rectal mean dose was inversely correlated with anterior score, but for PBS plans there was no association between rectal mean dose and anterior score. For both US and PBS plans, full bladder and empty bladder mean doses were correlated with anterior scores. For both US and PBS plans, femoral head mean doses were inversely correlated with anterior score. For US plans and a full bladder, 4 beam arrangements that included an anterior beam tied for the highest maximum prescription dose (MPD). For US plans and an empty bladder, the arrangement with 1 anterior and 2 anterior oblique beams achieved the highest MPD in the virtual dose-escalation study. The dose-escalation study did not differentiate beam arrangements for PBS. All arrangements in the dose-escalation study were limited by bladder constraints except for the arrangement with 2 posterior oblique beams. The benefits of anterior proton beams in the setting of prostate-rectum spacers appear to be proton modality dependent and may not extend to PBS.

  14. The effect of anterior proton beams in the setting of a prostate-rectum spacer

    Science.gov (United States)

    Christodouleas, John P.; Tang, Shikui; Susil, Robert C.; McNutt, Todd R.; Song, Danny Y.; Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha; DeWeese, Theodore L.; Lu, Hsiao-Ming; Both, Stefan

    2014-01-01

    Studies suggest that anterior beams with in vivo range verification would improve rectal dosimetry in proton therapy for prostate cancer. We investigated whether prostate-rectum spacers would enhance or diminish the benefits of anterior proton beams in these treatments. Twenty milliliters of hydrogel was injected between the prostate and rectum of a cadaver using a transperineal approach. Computed tomography (CT) and magnetic resonance (MR) images were used to generate 7 uniform scanning (US) and 7 single-field uniform dose pencil-beam scanning (PBS) plans with different beam arrangements. Pearson correlations were calculated between rectal, bladder, and femoral head dosimetric outcomes and beam arrangement anterior scores, which characterize the degree to which dose is delivered anteriorly. The overall quality of each plan was compared using a virtual dose-escalation study. For US plans, rectal mean dose was inversely correlated with anterior score, but for PBS plans there was no association between rectal mean dose and anterior score. For both US and PBS plans, full bladder and empty bladder mean doses were correlated with anterior scores. For both US and PBS plans, femoral head mean doses were inversely correlated with anterior score. For US plans and a full bladder, 4 beam arrangements that included an anterior beam tied for the highest maximum prescription dose (MPD). For US plans and an empty bladder, the arrangement with 1 anterior and 2 anterior oblique beams achieved the highest MPD in the virtual dose-escalation study. The dose-escalation study did not differentiate beam arrangements for PBS. All arrangements in the dose-escalation study were limited by bladder constraints except for the arrangement with 2 posterior oblique beams. The benefits of anterior proton beams in the setting of prostate-rectum spacers appear to be proton modality dependent and may not extend to PBS. PMID:23578497

  15. A New Adaptive Hungarian Mating Scheme in Genetic Algorithms

    Directory of Open Access Journals (Sweden)

    Chanju Jung

    2016-01-01

    Full Text Available In genetic algorithms, selection or mating scheme is one of the important operations. In this paper, we suggest an adaptive mating scheme using previously suggested Hungarian mating schemes. Hungarian mating schemes consist of maximizing the sum of mating distances, minimizing the sum, and random matching. We propose an algorithm to elect one of these Hungarian mating schemes. Every mated pair of solutions has to vote for the next generation mating scheme. The distance between parents and the distance between parent and offspring are considered when they vote. Well-known combinatorial optimization problems, the traveling salesperson problem, and the graph bisection problem are used for the test bed of our method. Our adaptive strategy showed better results than not only pure and previous hybrid schemes but also existing distance-based mating schemes.

  16. Quantum Communication Scheme Using Non-symmetric Quantum Channel

    International Nuclear Information System (INIS)

    Cao Haijing; Chen Zhonghua; Song Heshan

    2008-01-01

    A theoretical quantum communication scheme based on entanglement swapping and superdense coding is proposed with a 3-dimensional Bell state and 2-dimensional Bell state function as quantum channel. quantum key distribution and quantum secure direct communication can be simultaneously accomplished in the scheme. The scheme is secure and has high source capacity. At last, we generalize the quantum communication scheme to d-dimensional quantum channel

  17. A Haptic Feedback Scheme to Accurately Position a Virtual Wrist Prosthesis Using a Three-Node Tactor Array.

    Directory of Open Access Journals (Sweden)

    Andrew Erwin

    Full Text Available In this paper, a novel haptic feedback scheme, used for accurately positioning a 1DOF virtual wrist prosthesis through sensory substitution, is presented. The scheme employs a three-node tactor array and discretely and selectively modulates the stimulation frequency of each tactor to relay 11 discrete haptic stimuli to the user. Able-bodied participants were able to move the virtual wrist prosthesis via a surface electromyography based controller. The participants evaluated the feedback scheme without visual or audio feedback and relied solely on the haptic feedback alone to correctly position the hand. The scheme was evaluated through both normal (perpendicular and shear (lateral stimulations applied on the forearm. Normal stimulations were applied through a prototype device previously developed by the authors while shear stimulations were generated using an ubiquitous coin motor vibrotactor. Trials with no feedback served as a baseline to compare results within the study and to the literature. The results indicated that using normal and shear stimulations resulted in accurately positioning the virtual wrist, but were not significantly different. Using haptic feedback was substantially better than no feedback. The results found in this study are significant since the feedback scheme allows for using relatively few tactors to relay rich haptic information to the user and can be learned easily despite a relatively short amount of training. Additionally, the results are important for the haptic community since they contradict the common conception in the literature that normal stimulation is inferior to shear. From an ergonomic perspective normal stimulation has the potential to benefit upper limb amputees since it can operate at lower frequencies than shear-based vibrotactors while also generating less noise. Through further tuning of the novel haptic feedback scheme and normal stimulation device, a compact and comfortable sensory substitution

  18. A universal encoding scheme for MIMO transmission using a single active element for PSK modulation schemes

    DEFF Research Database (Denmark)

    Alrabadi, Osama; Papadias, C.B.; Kalis, A.

    2009-01-01

    A universal scheme for encoding multiple symbol streams using a single driven element (and consequently a single radio frequency (RF) frontend) surrounded by parasitic elements (PE) loaded with variable reactive loads, is proposed in this paper. The proposed scheme is based on creating a MIMO sys...

  19. TVD schemes in one and two space dimensions

    International Nuclear Information System (INIS)

    Leveque, R.J.; Goodman, J.B.; New York Univ., NY)

    1985-01-01

    The recent development of schemes which are second order accurate in smooth regions has made it possible to overcome certain difficulties which used to arise in numerical computations of discontinuous solutions of conservation laws. The present investigation is concerned with scalar conservation laws, taking into account the employment of total variation diminishing (TVD) schemes. The concept of a TVD scheme was introduced by Harten et al. (1976). Harten et al. first constructed schemes which are simultaneously TVD and second order accurate on smooth solutions. In the present paper, a summary is provided of recently conducted work in this area. Attention is given to TVD schemes in two space dimensions, a second order accurate TVD scheme in one dimension, and the entropy condition and spreading of rarefaction waves. 19 references

  20. Strategic purchasing and health system efficiency: A comparison of two financing schemes in Thailand.

    Science.gov (United States)

    Patcharanarumol, Walaiporn; Panichkriangkrai, Warisa; Sommanuttaweechai, Angkana; Hanson, Kara; Wanwong, Yaowaluk; Tangcharoensathien, Viroj

    2018-01-01

    Strategic purchasing is an essential health financing function. This paper compares the strategic purchasing practices of Thailand's two tax-financed health insurance schemes, the Universal Coverage Scheme (UCS) and the Civil Servant Medical Benefit Scheme (CSMBS), and identifies factors contributing to successful universal health coverage outcomes by analysing the relationships between the purchaser and government, providers and members. The study uses a cross-sectional mixed-methods design, including document review and interviews with 56 key informants. The Comptroller General Department (CGD) of Ministry of Finance manages CSMBS as one among civil servant welfare programmes. Their purchasing is passive. Fee for service payment for outpatient care has resulted in rapid cost escalation and overspending of their annual budget. In contrast, National Health Security Office (NHSO) manages purchasing for UCS, which undertakes a range of strategic purchasing actions, including applying closed ended provider payment, promoting primary healthcare's gate keeping functions, exercising collective purchasing power and engaging views of members in decision making process. This difference in purchasing arrangements resulted in expenditure per CSMBS member being 4 times higher than UCS in 2014. The governance of the purchaser organization, the design of the purchasing arrangements including incentives and use of information, and the institutional capacities to implement purchasing functions are essential for effective strategic purchasing which can improve health system efficiency as a whole.