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Sample records for based contact energies

  1. Optimal definition of inter-residual contact in globular proteins based on pairwise interaction energy calculations, its robustness, and applications.

    Science.gov (United States)

    Fačkovec, Boris; Vondrášek, Jiří

    2012-10-25

    Although a contact is an essential measurement for the topology as well as strength of non-covalent interactions in biomolecules and their complexes, there is no general agreement in the definition of this feature. Most of the definitions work with simple geometric criteria which do not fully reflect the energy content or ability of the biomolecular building blocks to arrange their environment. We offer a reasonable solution to this problem by distinguishing between "productive" and "non-productive" contacts based on their interaction energy strength and properties. We have proposed a method which converts the protein topology into a contact map that represents interactions with statistically significant high interaction energies. We do not prove that these contacts are exclusively stabilizing, but they represent a gateway to thermodynamically important rather than geometry-based contacts. The process is based on protein fragmentation and calculation of interaction energies using the OPLS force field and relies on pairwise additivity of amino acid interactions. Our approach integrates the treatment of different types of interactions, avoiding the problems resulting from different contributions to the overall stability and the different effect of the environment. The first applications on a set of homologous proteins have shown the usefulness of this classification for a sound estimate of protein stability.

  2. The hybrid energy storages based on batteries and ultracapacitors for contact microwelding

    Directory of Open Access Journals (Sweden)

    Bondarenko Yu. V.

    2014-08-01

    Full Text Available Micro resistance welding is an effective way to reliably join small-scale parts. It is widely used in electronics and instrument-making. The important particularities of micro resistance welding are pulse character of energy consumption, non-linear load and special form of current pulses. So, these particularities of welding process cause negative influence on the mains. One of the known ways to avoid it is to use autonomous power supplies for micro resistance welding machines. The important task for building autonomous power supplies is to choose effective energy storages, which have high capacity and small internal resistance, and which are capable to be charged and deliver energy to load very quickly. The solution of this task is seen in using hybrid energy storages, which include accumulators and ultracapacitors. The accumulators are able to provide high energy capacitance and the ultracapacitors are able to provide fast energy delivery. The possibility of application of hybrid energy storages, based on accumulator batteries and ultracapacitors, in micro resistance welding machines is confirmed with computer simulation. Two variants of hybrid energy storages are proposed. These hybrid energy storages have high power and dynamic characteristics, which are sufficient to generate current pulses for welding according to necessary settings.

  3. A new approach to influence contact angle and surface free energy of resin-based dental restorative materials.

    Science.gov (United States)

    Rüttermann, Stefan; Trellenkamp, Taina; Bergmann, Nora; Raab, Wolfgang H-M; Ritter, Helmut; Janda, Ralf

    2011-03-01

    The purpose of the present study was to identify novel delivery systems and active agents which increase the water contact angle and reduce the surface free energy when added to resin-based dental restorative materials. Two delivery systems based on zeolite or novel polymeric hollow beads (Poly-Pore), loaded with two low surface tension active agents (hydroxy functional polydimethylsiloxane and polydimethylsiloxane) or a polymerizable active agent (silicone polyether acrylate) were used to modify commonly formulated experimental dental resin composites. The non-modified resin was used as a standard (ST). Flexural strength, flexural modulus, water sorption, solubility, polymerization shrinkage, surface roughness Ra, contact angle θ, total surface free energy γS, and the apolar γSLW, polar γSAB, Lewis acid γS+ and base γS- components, and the active agents surface tensions γL were determined (Ptension active agents were found not to influence the physical properties but to significantly increase the water contact angle and thus reduce surface free energy of dental resin composites. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. Contact angle and surface free energy of experimental resin-based dental restorative materials after chewing simulation.

    Science.gov (United States)

    Rüttermann, Stefan; Beikler, Thomas; Janda, Ralf

    2014-06-01

    To investigate contact angle and surface free energy of experimental dental resin composites containing novel delivery systems of polymeric hollow beads and low-surface tension agents after chewing simulation test. A delivery system of novel polymeric hollow beads differently loaded with two low-surface tension agents was used in different amounts to modify commonly formulated experimental dental resin composites. The non-modified resin was used as standard. Surface roughness Ra, contact angle Θ, total surface free energy γS, its apolar γS(LW), polar γS(AB), Lewis acid γS(+) and base γS(-) terms were determined and the results prior to and after chewing simulation test were compared. Significance was phollow beads highly loaded with low-surface tension agents were found to significantly increase contact angle and thus to reduce surface free energy of experimental dental resin composites prior to and after chewing simulation test. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Amino acid empirical contact energy definitions for fold recognition in the space of contact maps

    Directory of Open Access Journals (Sweden)

    Fogolari Federico

    2003-02-01

    Full Text Available Abstract Background Contradicting evidence has been presented in the literature concerning the effectiveness of empirical contact energies for fold recognition. Empirical contact energies are calculated on the basis of information available from selected protein structures, with respect to a defined reference state, according to the quasi-chemical approximation. Protein-solvent interactions are estimated from residue solvent accessibility. Results In the approach presented here, contact energies are derived from the potential of mean force theory, several definitions of contact are examined and their performance in fold recognition is evaluated on sets of decoy structures. The best definition of contact is tested, on a more realistic scenario, on all predictions including sidechains accepted in the CASP4 experiment. In 30 out of 35 cases the native structure is correctly recognized and best predictions are usually found among the 10 lowest energy predictions. Conclusion The definition of contact based on van der Waals radii of alpha carbon and side chain heavy atoms is seen to perform better than other definitions involving only alpha carbons, only beta carbons, all heavy atoms or only backbone atoms. An important prerequisite for the applicability of the approach is that the protein structure under study should not exhibit anomalous solvent accessibility, compared to soluble proteins whose structure is deposited in the Protein Data Bank. The combined evaluation of a solvent accessibility parameter and contact energy allows for an effective gross screening of predictive models.

  6. Duality based contact shape optimization

    DEFF Research Database (Denmark)

    Vondrák, Vít; Dostal, Zdenek; Rasmussen, John

    2001-01-01

    An implementation of semi-analytic method for the sensitivity analysis in contact shape optimization without friction is described. This method is then applied to the contact shape optimization.......An implementation of semi-analytic method for the sensitivity analysis in contact shape optimization without friction is described. This method is then applied to the contact shape optimization....

  7. A piezoelectric active sensing method for quantitative monitoring of bolt loosening using energy dissipation caused by tangential damping based on the fractal contact theory

    Science.gov (United States)

    Wang, Furui; Huo, Linsheng; Song, Gangbing

    2018-01-01

    Monitoring of bolt looseness is essential for ensuring the safety and reliability of equipment and structures with bolted connections. It is well known that tangential damping has an important influence on energy dissipation during wave propagation across the bolted joints, which require different levels of preload. In this paper, the energy dissipation generated by tangential damping of the bolted joints under different bolt preloads was modeled analytically based on fractal contact theory, which took the imperfect interface into account. A saturation value exists with the increase of the bolt preload, and the center frequency of emitted signal is demonstrated to affect the received energy significantly. Compared with previous similar studies based on experimental techniques and numerical method, the investigation presented in this paper explains the phenomenon from the inherent mechanism, and achieves the accurate quantitative monitoring of bolt looseness directly, rather than an indirect failure index. Finally, the validity of the proposed method in this paper was demonstrated with an experimental study of a bolted joint with different preload levels.

  8. Effect of electrode contact area on the information content of the recorded electrogastrograms: An analysis based on Rényi entropy and Teager-Kaiser Energy

    Science.gov (United States)

    Alagumariappan, Paramasivam; Krishnamurthy, Kamalanand; Kandiah, Sundravadivelu; Ponnuswamy, Mannar Jawahar

    2017-06-01

    Electrogastrograms (EGG) are electrical signals originating from the digestive system, which are closely correlated with its mechanical activity. Electrogastrography is an efficient non-invasive method for examining the physiological and pathological states of the human digestive system. There are several factors such as fat conductivity, abdominal thickness, change in electrode surface area etc, which affects the quality of the recorded EGG signals. In this work, the effect of variations in the contact area of surface electrodes on the information content of the measured electrogastrograms is analyzed using Rényi entropy and Teager-Kaiser Energy (TKE). Two different circular cutaneous electrodes with approximate contact areas of 201.14 mm2 and 283.64 mm2, have been adopted and EGG signals were acquired using the standard three electrode protocol. Further, the information content of the measured EGG signals were analyzed using the computed values of entropy and energy. Results demonstrate that the information content of the measured EGG signals increases by 6.72% for an increase in the contact area of the surface electrode by 29.09%. Further, it was observed that the average energy increases with increase in the contact surface area. This work appears to be of high clinical significance since the accurate measurement of EGG signals without loss in its information content, is highly useful for the design of diagnostic assistance tools for automated diagnosis and mass screening of digestive disorders.

  9. Molecular dynamics study of the nanosized droplet spreading: The effect of the contact line forces on the kinetic energy dissipation

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hong Min [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Kondaraju, Sasidhar [Department of Mechanical Science, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 751013 (India); Lee, Jung Shin [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of); Suh, Youngho; Lee, Joonho H. [Samsung Electronics, Mechatronics R& D Center, Hwaseong-si, Gyeonggi-do 445-330 (Korea, Republic of); Lee, Joon Sang, E-mail: joonlee@yonsei.ac.kr [Department of Mechanical Engineering, Yonsei University, Seoul 120-749 (Korea, Republic of)

    2017-07-01

    Highlights: • Contact line forces, including friction and spreading forces are directly calculated. • Overall trends of variations in contact line forces during droplet spreading process show characteristics of contact line forces. • Detail relations of contact line forces and atomic kinetics in the contact line provide a clear evidence of the possible energy dissipation mechanism in droplet spreading process. - Abstract: Recent studies have revealed that contact line forces play an important role in the droplet spreading process. Despite their significance, the physics related to them has been studied only indirectly and the effect of contact line forces is still being disputed. We performed a molecular dynamics simulation and mimicked the droplet spreading process at the nanoscale. Based on the results of the simulation, the contact line forces were directly calculated. We found that the forces acting on the bulk and the contact line region showed different trends. Distinct positive and negative forces, contact line spreading, and friction forces were observed near the contact line. We also observed a strong dependency of the atomic kinetics in the contact line region on the variations in the contact line forces. The atoms of the liquid in the contact line region lost their kinetic energy due to the contact line friction force and became partially immobile on the solid surface. The results of the current study will be useful for understanding the role of the contact line forces on the kinetic energy dissipation in the contact line region.

  10. Surface Energy and Setting Process of Contacting Surfaces

    Directory of Open Access Journals (Sweden)

    M. V. Musokhranov

    2014-01-01

    Full Text Available The paper deals with a challenge in terms of ensuring an accuracy of the relative position of the conjugated surfaces that is to determine a coefficient of friction. To solve it, there is a proposal to use the surface energy, as a tool that influences the contacting parts nature. Presently, energy of the surface layers at best is only stated, but not used in practice.Analysis of the conditions of interaction between two contacting surfaces, such as seizing and setting cannot be explained only from the position of the roughness parameters. It is found that these phenomena are explained by the appearing gripe (setting bridges, which result from the energy of interaction between two or more adjacent surfaces. The emerging phenomenon such as micro welding, i.e. occurring bonds, is caused by the overflow of energy, according to the theory of physics, from the surface with a high level of energy to the surface with the smaller one to balance the system as a whole.The paper shows that through the use of process, controlling the depth of the surface layer and creating a certain structure, the energy level of the material as a whole can be specified. And this will allow us to provide the necessary performance and mechanical properties. It means to create as many gripe bridges as possible to ensure continuous positioning i.e. a fixed connection of the contacting surfaces.It was determined that to increase a value of the friction coefficient, the physical and mechanical properties of the surface layer of the parts material must be taken into account, namely, in the part body accumulate the energy to be consumed for forming the surface.The paper gives recommendations for including the parts of the surface energy in the qualitative indicators of characteristics. This will make a technologist, when routing a process, to choose such operations and modes to provide the designer-specified parameters not only of the accuracy and surface finish, but also of the

  11. Occupational contact dermatitis in the wind energy industry.

    Science.gov (United States)

    Lárraga-Piñones, G; Heras-Mendaza, F; Conde-Salazar, L

    2012-12-01

    In 2010, wind energy coverage in Spain increased by 16%, making the country the world's fourth largest producer in a fast-developing industry that is also a source of employment. Occupational skin diseases in this field have received little attention. The present study aims to describe the main characteristics of skin diseases affecting workers in the wind energy industry and the allergens involved. We performed a descriptive, observational study of workers from the wind energy industry with suspected contact dermatitis who were referred to the occupational dermatology clinic of the National School of Occupational Medicine (Escuela Nacional de Medicina del Trabajo) between 2009 and 2011. We took both a clinical history and an occupational history, and patients underwent a physical examination and patch testing with the materials used in their work. We studied 10 workers (8 men, 2 women), with a mean age of 33.7 years. The main finding was dermatitis, which affected the face, eyelids, forearms, and hands. Sensitization to epoxy resins was detected in 4 workers, 1 of whom was also sensitized to epoxy curing agents. One worker was sensitized to bisphenol F resin but had a negative result with epoxy resin from the standard series. In the 5 remaining cases, the final diagnosis was irritant contact dermatitis due to fiberglass. Occupational skin diseases are increasingly common in the wind energy industry. The main allergens are epoxy resins. Fiberglass tends to produce irritation. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

  12. Dynamics of contact line depinning during droplet evaporation based on thermodynamics.

    Science.gov (United States)

    Yu, Dong In; Kwak, Ho Jae; Doh, Seung Woo; Ahn, Ho Seon; Park, Hyun Sun; Kiyofumi, Moriyama; Kim, Moo Hwan

    2015-02-17

    For several decades, evaporation phenomena have been intensively investigated for a broad range of applications. However, the dynamics of contact line depinning during droplet evaporation has only been inductively inferred on the basis of experimental data and remains unclear. This study focuses on the dynamics of contact line depinning during droplet evaporation based on thermodynamics. Considering the decrease in the Gibbs free energy of a system with different evaporation modes, a theoretical model was developed to estimate the receding contact angle during contact line depinning as a function of surface conditions. Comparison of experimentally measured and theoretically modeled receding contact angles indicated that the dynamics of contact line depinning during droplet evaporation was caused by the most favorable thermodynamic process encountered during constant contact radius (CCR mode) and constant contact angle (CCA mode) evaporation to rapidly reach an equilibrium state during droplet evaporation.

  13. Energy. Political contacts at national, state and European level; Energie. Politikkontakte Bund, Land, Europa

    Energy Technology Data Exchange (ETDEWEB)

    Holzapfel, Andreas (ed.)

    2013-04-01

    The manual is in three sections: 1. Parliaments and governments, survey and organization; 2. Biographic section, with 304 biography; 3. Index of names. The first section informs on the organizational structure of parliaments and governments. The subject of energy is discussed three times, i.e. in 'Economics', 'Environment', and 'Research'. For each parliament, the members of the energy policy TCs are listed, followed by names and contact addresses of the senior officials and departments with contact data, both on a national, state, and European scale. The second section contains the biographies of energy policy experts of the German parliament and government, the sixteen land parliaments and governments, and the European Commissions. As the subject of energy is highly interdisciplinary, the authors selected the energy policy committees of the German parliament and state parliaments. The biographies of the committee members are presented in the text.

  14. Subharmonic energy-gap structure and heating effects in superconducting niobium point contacts

    DEFF Research Database (Denmark)

    Flensberg, K.; Hansen, Jørn Bindslev

    1989-01-01

    We present experimental data of the temperature-dependent subharmonic energy-gap structure (SGS) in the current-voltage (I-V) curves of superconducting niobium point contacts. The observed SGS is modified by heating effects. We construct a model of the quasiparticle conductance of metallic...... superconducting weak links that includes the heating effects self-consistently. Our model is combined with that of Octavio, Blonder, Klapwijk, and Tinkham [Phys. Rev. B 27, 6739 (1983)], which is based on the idea of multiple Andreev scattering in the contact. The shape and the temperature variation...

  15. Layer-by-layer polyelectrolyte films for contact electric energy harvesting

    International Nuclear Information System (INIS)

    Guo, X D; Helseth, L E

    2015-01-01

    We report how self-assembly of polyelectrolyte thin films alters the contact electrification of polyimide polymer films used in contact based triboelectric energy harvesting systems. Polyimide films of the same size do produce a very small current when brought into contact. However, by covering one of the polyimide films with a polyelectrolyte thin film terminated by positively charged poly(allylamine hydrochloride) (PAH), the current is reversed and a much larger current and voltage are generated upon contact with the other polyimide film. A similar increase in contact current is not seen for polyelectrolyte thin films terminated by the negatively charged poly(sodium 4-styrenesulfonate). The PAH-terminated Kapton films are used to create an energy harvesting system providing a voltage of about 60 V and a current of 10 μA. At an average power of 11 μW for a load resistance of 100 MΩ, the energy harvester is able to power several light emitting diodes. Further studies on the contact electrification of the polyelectrolyte demonstrate that nanostructuring of the polymer surface using reactive ion etching does not give rise to polarity reversal. This is explained as hidden pockets of charge not accessible to PAH molecules, but which become accessible when the polymer is put under stress. Although the current originating for a PAH-terminated multilayer film does initially have the opposite sign to that of bare polyimide, it is found that the polarity will switch after subjecting it to a periodical mechanical force. Characteristic changes in current signatures associated with the switch are found, and are interpreted as mechanical interpenetration of the charged layers. (paper)

  16. Micro-contact based modelling of abrasive wear

    NARCIS (Netherlands)

    Masen, Marc Arthur; de Rooij, Matthias B.; Schipper, Dirk J.

    2005-01-01

    A model that describes the abrasive wear between a hard and rough surface and a softer and smooth surface is developed. The contact between these two solids is modelled based on micro-contacts [M.A. Masen, M.B. de Rooij, Abrasive wear between rough surfaces in deep drawing, in: Proceedings of the

  17. Total energy expenditure estimated using foot-ground contact pedometry.

    Science.gov (United States)

    Hoyt, Reed W; Buller, Mark J; Santee, William R; Yokota, Miyo; Weyand, Peter G; Delany, James P

    2004-02-01

    Routine walking and running, by increasing daily total energy expenditure (TEE), can play a significant role in reducing the likelihood of obesity. The objective of this field study was to compare TEE estimated using foot-ground contact time (Tc)-pedometry (TEE(PEDO)) with that measured by the criterion doubly labeled water (DLW) method. Eight male U.S. Marine test volunteers [27 +/- 4 years of age (mean +/- SD); weight = 83.2 +/- 10.7 kg; height = 182.2 +/- 4.5 cm; body fat = 17.0 +/- 2.9%] engaged in a field training exercise were studied over 2 days. TEE(PEDO) was defined as (calculated resting energy expenditure + estimated thermic effect of food + metabolic cost of physical activity), where physical activity was estimated by Tc-pedometry. Tc-pedometry was used to differentiate inactivity, activity other than exercise (i.e., non-exercise activity thermogenesis, or NEAT), and the metabolic cost of locomotion (M(LOCO)), where M(LOCO) was derived from total weight (body weight + load weight) and accelerometric measurements of Tc. TEE(PEDO) data were compared with TEEs measured by the DLW (2H2(18)O) method (TEE(DLW)): TEE(DLW) = 15.27 +/- 1.65 MJ/day and TEE(PEDO) = 15.29 +/- 0.83 MJ/day. Mean bias (i.e., TEE(PEDO) - TEE(DLW)) was 0.02 MJ, and mean error (SD of individual differences between TEE(PEDO) and TEE(DLW)) was 1.83 MJ. The Tc-pedometry method provided a valid estimate of the average TEE of a small group of physically active subjects where walking was the dominant activity.

  18. Improvement of Energy Efficiency and Environmental Safety of Thermal Energy Through the Implementation of Contact Energy Exchange Processes

    Science.gov (United States)

    Varlamov, Gennadii Borysovich; Romanova, Kateryna Alexandrovna; Nazarova, Iryna; Daschenko, Olga; Kapustiansky, Andry

    2017-12-01

    Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation `Aquarius' and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally `generate' the clean water, which can be used for technical purposes.

  19. Improvement of Energy Efficiency and Environmental Safety of Thermal Energy Through the Implementation of Contact Energy Exchange Processes

    Directory of Open Access Journals (Sweden)

    Varlamov Gennadii Borysovich

    2017-12-01

    Full Text Available Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation ‘Aquarius’ and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally ‘generate’ the clean water, which can be used for technical purposes.

  20. Cryotrons based on a simultaneously distributed Josephson contact

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtin, P.A.; Lapir, G.M.; Makhov, V.I.; Samus, A.N.; Semenov, V.K.; Tyablikov, A.V.

    1982-01-01

    The features of the construction of cryotrons based on an evenly distributed Josephson contact are examined. The possibility is demonstrated of producing cryotrons with an assigned form of the controlling characteristic through the spatial isolation of the transport and controlling streams. The theoretical and experimental controlling characteristics of cryotrons based on bridges of variable thickness with connectors of normal metal are cited. The proposed principles of cryotron production are also suitable for other types of Josephson contacts.

  1. Is judging time-to-contact based on 'tau'?

    NARCIS (Netherlands)

    Smeets, J. B J; Brenner, Eli; Trébuchet, Sonia; Mestre, Daniel R.

    1996-01-01

    An investigation was undertaken into whether judgments of time-to-contact between a laterally moving object and a bar are based on the direct perception of an optical variable (tau), or on the ratio between the perceived distance and perceived velocity of the object. A moving background was used to

  2. Neurosurgery contact handheld probe based on sapphire shaped crystal

    Science.gov (United States)

    Shikunova, I. A.; Stryukov, D. O.; Rossolenko, S. N.; Kiselev, A. M.; Kurlov, V. N.

    2017-01-01

    A handheld contact probe based on sapphire shaped crystal is developed for intraoperative spectrally-resolved optical diagnostics, laser coagulation and aspiration of malignant brain tissue. The technology was integrated into the neurosurgical workflow for intraoperative real-time identification and removing of invasive brain cancer.

  3. Energy Consumption Analysis of Particle Crushing on Structural Contact Surface under High Pressure Shear

    Science.gov (United States)

    Tan, Junkun; Guo, Jiaqi

    2017-12-01

    The experimental study on the energy relationship between the coarse sand with different water content and the concrete interface with different hardness and roughness is carried out, through the high stress direct shear apparatus. Experimental results show that the growth rate of shear energy dissipation of sand - structure contact surface is slowing down with the increase of roughness, even negative; The shear energy dissipation of concrete with different hardness decreases first and then increases with the increase of water content, The crushing energy consumption is the lowest when water content is 16%; The shear energy dissipation at different moisture content increases with the increase of the contact strength of concrete structure.

  4. Energy transfer, volumetric expansion, and removal of oral biofilms by non-contact brushing

    NARCIS (Netherlands)

    Busscher, H. J.; Jager, D.; Finger, G.; Schaefer, N.; van der Mei, H. C.

    Non-contact removal of oral biofilms offers advantages beyond the reach of bristles, but it is unknown how energy transfer for removal from brush-to-biofilm occurs. In the present study we evaluated non-contact, oral biofilm removal by oscillating-rotating and sonic toothbrushes, and their acoustic

  5. Evaluation of Tire/Surfacing/Base Contact Stresses and Texture Depth

    Directory of Open Access Journals (Sweden)

    W.J.vdM. Steyn

    2015-03-01

    Full Text Available Tire rolling resistance has a major impact on vehicle fuel consumption. Rolling resistance is the loss of energy due to the interaction between the tire and the pavement surface. This interaction is a complicated combination of stresses and strains which depend on both tire and pavement related factors. These include vehicle speed, vehicle weight, tire material and type, road camber, tire inflation pressure, pavement surfacing texture etc. In this paper the relationship between pavement surface texture depth and tire/surfacing contact stress and area is investigated. Texture depth and tire/surfacing contact stress were measured for a range of tire inflation pressures on five different pavement surfaces. In the analysis the relationship between texture and the generated contact stresses as well as the contact stress between the surfacing and base layer are presented and discussed, and the anticipated effect of these relationships on the rolling resistance of vehicles on the surfacings, and subsequent vehicle fuel economy discussed.

  6. Underactuated Potential Energy Shaping with Contact Constraints: Application to a Powered Knee-Ankle Orthosis.

    Science.gov (United States)

    Lv, Ge; Gregg, Robert D

    2018-01-01

    Body-weight support (i.e., gravity compensation) is an effective clinical tool for gait rehabilitation after neurological impairment. Body-weight supported training systems have been developed to help patients regain mobility and confidence during walking, but conventional systems constrain the patient's treatment in clinical environments. We propose that this challenge could be addressed by virtually providing patients with bodyweight support through the actuators of a powered orthosis (or exoskeleton) utilizing potential energy shaping control. However, the changing contact conditions and degrees of underactuation encountered during human walking present significant challenges to consistently matching a desired potential energy for the human in closed loop. We therefore derive a generalized matching condition for shaping Lagrangian systems with holonomic contact constraints. By satisfying this matching condition for four phases of gait, we derive passivity-based control laws to achieve virtual body-weight support through a powered knee-ankle orthosis. We demonstrate beneficial effects of virtual body-weight support in simulations of a human-like biped model, indicating the potential clinical value of this proposed control approach.

  7. Experimental determination of the thermal contact conductance between two solid surfaces by the energy pulse technique

    International Nuclear Information System (INIS)

    Rubin, Gerson Antonio

    1979-01-01

    An experimental procedure for the determination of the thermal contact conductance between two solid surfaces as a function of the contact pressure and the energy of the laser radiation has been developed using the laser pulse method. A rubi laser with variable energy levels was employed as a radiating pulse energy source. The laser beam was allowed to impinge perpendicularly on the front face of a electrolytic iron 73 4 . The temperature fluctuations resulting on the back surface of the sample was detected by a thermocouple, which Is coupled to a PDP-11/45 Computer 32 Kbytes of memory, through a Analog-Digital Converter. A theoretical function, derived exclusively for the problem mentioned in this work, was adjusted by a method of least square fitting of experimental results. This adjustment yielded the value of a parameter related to the contact conductance between two surfaces. The experimental error obtained for the thermal contact conductance was +- 4.9%. (author)

  8. Quasi-emf under contact interaction of bodies during cutting as electron potential energy measurement

    International Nuclear Information System (INIS)

    Vasil'ev, S.V.

    1989-01-01

    It is shown that cutting quasi-emf measured under the contact interaction of a number of pure metals (molybdenum, titanium, niobium, iron, copper, beryllium, lead, nickel and cobalt), graphite and silicon correlates closely with Fermi levels calculated for them, i.e. it reflects the potential electron energy. Correlation is observed at different cutting rate (temperature) and consequently at different electron kinetic energy

  9. Simulation Study of AC Contactor Dynamic Contacts Contact Pressure Based on ADAMS

    Directory of Open Access Journals (Sweden)

    Gu Yungao

    2015-01-01

    Full Text Available A multi-body dynamics simulation model of CJ20-25 AC contactor was established with Pro/E(Pro/Engineerin this paper. A coupling simulation with machine, electric, magnetic on the contactor has been achieved in this model. Dynamic parameters which were called use the secondary development technology of ADAMS. The dynamic contact pressure signal of an AC contactor was obtained with ADAMS’s own simultaneous solution such as electromagnetic suction, kinematics and dynamics equations. The simulation results and actual measurement of contactor contact pressure signals are very similar. However, the complexity of the measured contacts vibration is greater than the simulation results because the actual working condition is more complex. This result provides a theoretical foundation to the dynamic contacts contact pressure test.

  10. Overhead contact lines according to TSI Energy, installation design and technical acceptance; Oberleitungsanlagen nach TSI Energie. Planung und Abnahme

    Energy Technology Data Exchange (ETDEWEB)

    Schnadhorst, Kai [Balfour Beatty Rail GmbH, Essen (Germany); Tessun, Heinz [Balfour Beatty Rail GmbH, Muenchen (Germany)

    2011-04-15

    Comparison of the issues of 2002 and 2008 of the technical specification for interoperability relating to the ''energy'' sub-system of the trans-European high-speed rail system (TSI) influences, especially of the permissible wind deviation to the standard overhead contact line of Deutsche Bahn (DB). Installation design, acceptance, construction and technical approval of an overhead contact line in accordance with TSI. (orig.)

  11. The role of adhesion energy in controlling cell?cell contacts

    OpenAIRE

    Ma?tre, Jean-L?on; Heisenberg, Carl-Philipp

    2011-01-01

    Recent advances in microscopy techniques and biophysical measurements have provided novel insight into the molecular, cellular and biophysical basis of cell adhesion. However, comparably little is known about a core element of cell?cell adhesion?the energy of adhesion at the cell?cell contact. In this review, we discuss approaches to understand the nature and regulation of adhesion energy, and propose strategies to determine adhesion energy between cells in vitro and in vivo.

  12. Hydrogen energy based on nuclear energy

    International Nuclear Information System (INIS)

    2002-06-01

    A concept to produce hydrogen of an energy carrier using nuclear energy was proposed since 1970s, and a number of process based on thermochemical method has been investigated after petroleum shock. As this method is used high temperature based on nuclear reactors, these researches are mainly carried out as a part of application of high temperature reactors, which has been carried out at an aim of the high temperature reactor application in the Japan Atomic Energy Research Institute. On October, 2000, the 'First International Conference for Information Exchange on Hydrogen Production based on Nuclear Energy' was held by auspice of OECD/NEA, where hydrogen energy at energy view in the 21st Century, technology on hydrogen production using nuclear energy, and so on, were published. This commentary was summarized surveys and researches on hydrogen production using nuclear energy carried out by the Nuclear Hydrogen Research Group established on January, 2001 for one year. They contains, views on energy and hydrogen/nuclear energy, hydrogen production using nuclear energy and already finished researches, methods of hydrogen production using nuclear energy and their present conditions, concepts on production plants of nuclear hydrogen, resources on nuclear hydrogen production and effect on global environment, requests from market and acceptability of society, and its future process. (G.K.)

  13. MIDP-based Realization of a Simple Phone Contact Book

    Science.gov (United States)

    Niu, Yan; Xia, Heng; Huan, Lele

    This paper describes the architecture of J2ME and MIDP specification, use the Java language to implement a simple cell phone contact book system, to complete a contact to add, delete, modify, query functions. Different from existing phone contacts, it can run any MIDP-enabled mobile phones, avoid the question of using tool software into and out of phone contact book after user change phone.

  14. A damage mechanics based general purpose interface/contact element

    Science.gov (United States)

    Yan, Chengyong

    Most of the microelectronics packaging structures consist of layered substrates connected with bonding materials, such as solder or epoxy. Predicting the thermomechanical behavior of these multilayered structures is a challenging task in electronic packaging engineering. In a layered structure the most complex part is always the interfaces between the strates. Simulating the thermo-mechanical behavior of such interfaces, is the main theme of this dissertation. The most commonly used solder material, Pb-Sn alloy, has a very low melting temperature 180sp°C, so that the material demonstrates a highly viscous behavior. And, creep usually dominates the failure mechanism. Hence, the theory of viscoplasticity is adapted to describe the constitutive behavior. In a multilayered assembly each layer has a different coefficient of thermal expansion. Under thermal cycling, due to heat dissipated from circuits, interfaces and interconnects experience low cycle fatigue. Presently, the state-of-the art damage mechanics model used for fatigue life predictions is based on Kachanov (1986) continuum damage model. This model uses plastic strain as a damage criterion. Since plastic strain is a stress path dependent value, the criterion does not yield unique damage values for the same state of stress. In this dissertation a new damage evolution equation based on the second law of thermodynamic is proposed. The new criterion is based on the entropy of the system and it yields unique damage values for all stress paths to the final state of stress. In the electronics industry, there is a strong desire to develop fatigue free interconnections. The proposed interface/contact element can also simulate the behavior of the fatigue free Z-direction thin film interconnections as well as traditional layered interconnects. The proposed interface element can simulate behavior of a bonded interface or unbonded sliding interface, also called contact element. The proposed element was verified against

  15. Perceptron learning of pairwise contact energies for proteins incorporating the amino acid environment

    Science.gov (United States)

    Heo, Muyoung; Kim, Suhkmann; Moon, Eun-Joung; Cheon, Mookyung; Chung, Kwanghoon; Chang, Iksoo

    2005-07-01

    Although a coarse-grained description of proteins is a simple and convenient way to attack the protein folding problem, the construction of a global pairwise energy function which can simultaneously recognize the native folds of many proteins has resulted in partial success. We have sought the possibility of a systematic improvement of this pairwise-contact energy function as we extended the parameter space of amino acids, incorporating local environments of amino acids, beyond a 20×20 matrix. We have studied the pairwise contact energy functions of 20×20 , 60×60 , and 180×180 matrices depending on the extent of parameter space, and compared their effect on the learnability of energy parameters in the context of a gapless threading, bearing in mind that a 20×20 pairwise contact matrix has been shown to be too simple to recognize the native folds of many proteins. In this paper, we show that the construction of a global pairwise energy function was achieved using 1006 training proteins of a homology of less than 30%, which include all representatives of different protein classes. After parametrizing the local environments of the amino acids into nine categories depending on three secondary structures and three kinds of hydrophobicity (desolvation), the 16290 pairwise contact energies (scores) of the amino acids could be determined by perceptron learning and protein threading. These could simultaneously recognize all the native folds of the 1006 training proteins. When these energy parameters were tested on the 382 test proteins of a homology of less than 90%, 370 (96.9%) proteins could recognize their native folds. We set up a simple thermodynamic framework in the conformational space of decoys to calculate the unfolded fraction and the specific heat of real proteins. The different thermodynamic stabilities of E.coli ribonuclease H (RNase H) and its mutants were well described in our calculation, agreeing with the experiment.

  16. The Use of Energy Storage Systems for Supporting the Voltage Needs of Urban and Suburban Railway Contact Lines

    Directory of Open Access Journals (Sweden)

    Enrico Pagano

    2013-03-01

    Full Text Available The paper aims to contribute to the use of electric double layer capacitor (EDLC sets for boosting voltages of contact lines in urban and suburban railway traction systems. Different electrical configurations of contact lines are considered and investigated. For each of them, proper mathematical models are suggested to evaluate the electrical performances of the contact lines. They give rise, also, to sample design procedures for the sizing of the most appropriate energy storage systems, to be distributed along the lines, for boosting line voltages and avoiding undesired voltage drops. A numerical example based on the “Cumana” suburban Naples railway network is presented to give an idea of the weights and sizes of electric double layer capacitors needed to boost the voltage of a sample contact line. In particular, three different EDLC systems, for a overall installed energy of 9.6 kWh, have been placed nearby the stations presenting the highest voltage drops during the most representative situation of trains’ service. The new voltage drop is equal to 32% of that obtained in absence of EDLCs.

  17. Parameterizing ice nucleation rates using contact angle and activation energy derived from laboratory data

    Directory of Open Access Journals (Sweden)

    J.-P. Chen

    2008-12-01

    Full Text Available The rate of ice nucleation in clouds is not easily determined and large discrepancies exist between model predictions and actual ice crystal concentration measured in clouds. In an effort to improve the parameterization of ice nucleating in cloud models, we investigate the rate of heterogeneous ice nucleation under specific ambient conditions by knowing the sizes as well as two thermodynamic parameters of the ice nuclei – contact angle and activation energy. Laboratory data of freezing and deposition nucleation modes were analyzed to derive inversely the two thermodynamic parameters for a variety of ice nuclei, including mineral dusts, bacteria, pollens, and soot particles. The analysis considered the Zeldovich factor for the adjustment of ice germ formation, as well as the solute and curvature effects on surface tension; the latter effects have strong influence on the contact angle. Contact angle turns out to be a more important factor than the activation energy in discriminating the nucleation capabilities of various ice nuclei species. By extracting these thermodynamic parameters, laboratory results can be converted into a formulation that follows classical nucleation theory, which then has the flexibility of incorporating factors such as the solute effect and curvature effect that were not considered in the experiments. Due to various uncertainties, contact angle and activation energy derived in this study should be regarded as "apparent" thermodynamics parameters.

  18. Contact in the Classroom: Developing a Program Model for Youth Mental Health Contact-Based Anti-stigma Education.

    Science.gov (United States)

    Chen, Shu-Ping; Koller, Michelle; Krupa, Terry; Stuart, Heather

    2016-04-01

    This study evaluated eighteen Canadian anti-stigma programs targeting high-school students. The purpose was to identify critical domains and develop a program model of contact-based interventions. Three steps were implemented. The first step involved collecting program information through twenty in-depth interviews with stakeholders and field observations of seven programs. The second step involved constructing critical ingredients into domains for conceptual clarity and component modeling. The third step involved validating the program model by stakeholders review and initial fidelity testing with program outcomes. A program model with an overarching theme "engaging contact reduces stigma" and three underlying constructs (speakers, message, and interaction) were developed. Within each construct three specific domains were identified to explain the concepts. Connection, engagement, and empowerment are critical domains of anti-stigma programs for the youth population. Findings from this study have built on the scientific knowledge about the change theory underpinning youth contact-based intervention.

  19. Low-Velocity Impact Wear Behavior of Ball-to-Flat Contact Under Constant Kinetic Energy

    Science.gov (United States)

    Wang, Zhang; Cai, Zhen-bing; Chen, Zhi-qiang; Sun, Yang; Zhu, Min-hao

    2017-11-01

    The impact tests were conducted on metallic materials with different bulk hardness and Young's moduli. Analysis of the dynamics response during the tribological process showed that the tested materials had similar energy absorption, where the peak contact force increased as the tests continued. Moreover, wear volume decreased with the increase in Young's modulus of metals, except for Cr with a relatively low hardness. Wear rate was gradually reduced to a steady stage with increasing cycles, which was attributed to the decrease in contact stress and work-hardening effect. The main wear mechanism of impact was characterized by delamination, and the specific surface degradation mechanisms were depending on the mechanical properties of materials. The absorbed energy was used to the propagation of micro-cracks in the subsurface instead of plastic deformation, when resistance of friction wear and plastic behavior was improved. Hence, both the hardness and Young's modulus played important roles in the impact wear of metallic materials.

  20. DETERMINING THE VALUE OF SURFACE FREE ENERGY ON THE BASIS OF THE CONTACT ANGLE

    Directory of Open Access Journals (Sweden)

    Mariusz Kłonica

    2017-03-01

    Full Text Available This paper presents the results of tests concerning the value of surface free energy on the basis of measurements of contact angle with measure liquids: distilled water and diiodomethane. The surface of steel-316L samples was modified in an ozone atmosphere, and the concentration of ozone and the conditioning time of the samples in the reaction chamber were changed. The results of tests concerning the measurements of the value of surface free energy were subject to analysis. Also analysed were the components of SFE: the polar and dispersive components. The obtained test results were analysed in statistical terms. The paper ends with conclusions.

  1. Contact-based ligand-clustering approach for the identification of active compounds in virtual screening

    Directory of Open Access Journals (Sweden)

    Mantsyzov AB

    2012-09-01

    Full Text Available Alexey B Mantsyzov,1 Guillaume Bouvier,2 Nathalie Evrard-Todeschi,1 Gildas Bertho11Université Paris Descartes, Sorbonne, Paris, France; 2Institut Pasteur, Paris, FranceAbstract: Evaluation of docking results is one of the most important problems for virtual screening and in silico drug design. Modern approaches for the identification of active compounds in a large data set of docked molecules use energy scoring functions. One of the general and most significant limitations of these methods relates to inaccurate binding energy estimation, which results in false scoring of docked compounds. Automatic analysis of poses using self-organizing maps (AuPosSOM represents an alternative approach for the evaluation of docking results based on the clustering of compounds by the similarity of their contacts with the receptor. A scoring function was developed for the identification of the active compounds in the AuPosSOM clustered dataset. In addition, the AuPosSOM efficiency for the clustering of compounds and the identification of key contacts considered as important for its activity, were also improved. Benchmark tests for several targets revealed that together with the developed scoring function, AuPosSOM represents a good alternative to the energy-based scoring functions for the evaluation of docking results.Keywords: scoring, docking, virtual screening, CAR, AuPosSOM

  2. Rolling contact fatigue testing of peek based composites

    Directory of Open Access Journals (Sweden)

    Petrogalli C.

    2010-06-01

    Full Text Available Rolling contact fatigue phenomenon was investigated on unfilled PEEK and on three different PEEK composites: 10% carbon micro-fiber, graphite and PTFE filled matrix, 30% carbon micro-fiber filled matrix, 30% glass micro-fiber filled matrix. For this aim, roller-shaped specimens were machined from extruded bars of these materials and subjected to rolling contact tests at different contact pressure levels by means of a four roller machine. Contact pressure-life diagrams and wear rates were so obtained and compared, highlighting a relationship with monotonic and hardness materials properties. Microscopic observations of contact surfaces and transversal section of the specimens also allowed observing the damage mechanisms occurred in the materials tested and the effects of the filler. In particular way, deep radial cracks appeared on unfilled PEEK, while spalling and delamination phenomena where found on composites. Diffuse microcracks were found at the filler-matrix interface of the composites specimens, confirming that the fatigue life of these materials is essentially determined by the crack propagation phase, also under rolling contact loading.

  3. Contact Resistance and Channel Conductance of Graphene Field-Effect Transistors under Low-Energy Electron Irradiation

    Directory of Open Access Journals (Sweden)

    Filippo Giubileo

    2016-11-01

    Full Text Available We studied the effects of low-energy electron beam irradiation up to 10 keV on graphene-based field effect transistors. We fabricated metallic bilayer electrodes to contact mono- and bi-layer graphene flakes on SiO2, obtaining specific contact resistivity ρ c ≈ 19 k Ω · µ m 2 and carrier mobility as high as 4000 cm2·V−1·s−1. By using a highly doped p-Si/SiO2 substrate as the back gate, we analyzed the transport properties of the device and the dependence on the pressure and on the electron bombardment. We demonstrate herein that low energy irradiation is detrimental to the transistor current capability, resulting in an increase in contact resistance and a reduction in carrier mobility, even at electron doses as low as 30 e−/nm2. We also show that irradiated devices recover their pristine state after few repeated electrical measurements.

  4. Maximized Effective Energy Output of Contact-Separation-Triggered Triboelectric Nanogenerators as Limited by Air Breakdown

    KAUST Repository

    Zi, Yunlong

    2017-05-02

    Recent progress in triboelectric nanogenerators (TENGs) has demonstrated their promising potential as a high-efficiency mechanical energy harvesting technology, and plenty of effort has been devoted to improving the power output by maximizing the triboelectric surface charge density. However, due to high-voltage air breakdown, most of the enhanced surface charge density brought by material/surface optimization or external ion injection is not retainable or usable for electricity generation during the operation of contact-separation-triggered TENGs. Here, the existence of the air breakdown effect in a contact-separation mode TENG with a low threshold surface charge density of ≈40–50 µC m−2 is first validated under the high impedance external load, and then followed by the theoretical study of the maximized effective energy output as limited by air breakdown for contact-separation-triggered TENGs. The effects of air pressure and gas composition are also studied and propose promising solutions for reducing the air breakdown effect. This research provides a crucial fundamental study for TENG technology and its further development and applications.

  5. Non-contact versus contact-based sensing methodologies for in-home upper arm robotic rehabilitation.

    Science.gov (United States)

    Howard, Ayanna; Brooks, Douglas; Brown, Edward; Gebregiorgis, Adey; Chen, Yu-Ping

    2013-06-01

    In recent years, robot-assisted rehabilitation has gained momentum as a viable means for improving outcomes for therapeutic interventions. Such therapy experiences allow controlled and repeatable trials and quantitative evaluation of mobility metrics. Typically though these robotic devices have been focused on rehabilitation within a clinical setting. In these traditional robot-assisted rehabilitation studies, participants are required to perform goal-directed movements with the robot during a therapy session. This requires physical contact between the participant and the robot to enable precise control of the task, as well as a means to collect relevant performance data. On the other hand, non-contact means of robot interaction can provide a safe methodology for extracting the control data needed for in-home rehabilitation. As such, in this paper we discuss a contact and non-contact based method for upper-arm rehabilitation exercises that enables quantification of upper-arm movements. We evaluate our methodology on upper-arm abduction/adduction movements and discuss the advantages and limitations of each approach as applied to an in-home rehabilitation scenario.

  6. A fully discrete energy stable scheme for a phase filed moving contact line model with variable densities and viscosities

    KAUST Repository

    Zhu, Guangpu

    2018-01-26

    In this paper, a fully discrete scheme which considers temporal and spatial discretizations is presented for the coupled Cahn-Hilliard equation in conserved form with the dynamic contact line condition and the Navier-Stokes equation with the generalized Navier boundary condition. Variable densities and viscosities are incorporated in this model. A rigorous proof of energy stability is provided for the fully discrete scheme based on a semi-implicit temporal discretization and a finite difference method on the staggered grids for the spatial discretization. A splitting method based on the pressure stabilization is implemented to solve the Navier-Stokes equation, while the stabilization approach is also used for the Cahn-Hilliard equation. Numerical results in both 2-D and 3-D demonstrate the accuracy, efficiency and decaying property of discrete energy of the proposed scheme.

  7. A pairwise residue contact area-based mean force potential for discrimination of native protein structure

    Directory of Open Access Journals (Sweden)

    Pezeshk Hamid

    2010-01-01

    Full Text Available Abstract Background Considering energy function to detect a correct protein fold from incorrect ones is very important for protein structure prediction and protein folding. Knowledge-based mean force potentials are certainly the most popular type of interaction function for protein threading. They are derived from statistical analyses of interacting groups in experimentally determined protein structures. These potentials are developed at the atom or the amino acid level. Based on orientation dependent contact area, a new type of knowledge-based mean force potential has been developed. Results We developed a new approach to calculate a knowledge-based potential of mean-force, using pairwise residue contact area. To test the performance of our approach, we performed it on several decoy sets to measure its ability to discriminate native structure from decoys. This potential has been able to distinguish native structures from the decoys in the most cases. Further, the calculated Z-scores were quite high for all protein datasets. Conclusions This knowledge-based potential of mean force can be used in protein structure prediction, fold recognition, comparative modelling and molecular recognition. The program is available at http://www.bioinf.cs.ipm.ac.ir/softwares/surfield

  8. Phonon Transport through Nanoscale Contact in Tip-Based Thermal Analysis of Nanomaterials.

    Science.gov (United States)

    Dulhani, Jay; Lee, Bong Jae

    2017-07-28

    Nanomaterials have been actively employed in various applications for energy and sustainability, such as biosensing, gas sensing, solar thermal energy conversion, passive radiative cooling, etc. Understanding thermal transports inside such nanomaterials is crucial for optimizing their performance for different applications. In order to probe the thermal transport inside nanomaterials or nanostructures, tip-based nanoscale thermometry has often been employed. It has been well known that phonon transport in nanometer scale is fundamentally different from that occurred in macroscale. Therefore, Fourier's law that relies on the diffusion approximation is not ideally suitable for describing the phonon transport occurred in nanostructures and/or through nanoscale contact. In the present study, the gray Boltzmann transport equation (BTE) is numerically solved using finite volume method. Based on the gray BTE, phonon transport through the constriction formed by a probe itself as well as the nanoscale contact between the probe tip and the specimen is investigated. The interaction of a probe and a specimen (i.e., treated as a substrate) is explored qualitatively by analyzing the temperature variation in the tip-substrate configuration. Besides, each contribution of a probe tip, tip-substrate interface, and a substrate to the thermal resistance are analyzed for wide ranges of the constriction ratio of the probe.

  9. Forest biomass-based energy

    Science.gov (United States)

    Janaki R. R. Alavalapati; Pankaj Lal; Andres Susaeta; Robert C. Abt; David N. Wear

    2013-01-01

    Key FindingsHarvesting woody biomass for use as bioenergy is projected to range from 170 million to 336 million green tons by 2050, an increase of 54 to 113 percent over current levels.Consumption projections for forest biomass-based energy, which are based on Energy Information Administration projections, have a high level of...

  10. Determination of the Contact Angle Based on the Casimir Effect

    Science.gov (United States)

    Mazuruk, Konstantin; Volz, Martin P.

    2015-01-01

    On a macroscopic scale, a nonreactive liquid partially covering a homogeneous solid surface will intersect the solid at an angle called the contact angle. For molten metals and semiconductors, the contact angle is materially dependent upon both the solid and liquid and typical values fall in the range 80-170 deg, depending on the crucible material. On a microscopic scale, there does not exist a precise and sharp contact angle but rather the liquid and solid surfaces merge smoothly and continuously. Consider the example of the so called detached Bridgman crystal growth process. In this technique, a small gap is formed between the growing crystal and the crucible. At the crystal/melt interface, a meniscus ring is formed. Its width can be in the range of a few micrometers, approaching a microscopic scale. It then becomes questionable to describe the shape of this meniscus by the contact angle. A more advanced treatment of the interface is needed and here we propose such a refined model. The interaction of the liquid surface with the solid can be calculated by considering two forces: a short-range repulsive force and a longer range (up to a few micrometers) Casimir or van der Waals force.

  11. Alternative current source based Schottky contact with additional electric field

    Science.gov (United States)

    Mamedov, R. K.; Aslanova, A. R.

    2017-07-01

    Additional electric field (AEF) in the Schottky contacts (SC) that covered the peripheral contact region wide and the complete contact region narrow (as TMBS diode) SC. Under the influence of AEF is a redistribution of free electrons produced at certain temperatures of the semiconductor, and is formed the space charge region (SCR). As a result of the superposition of the electric fields SCR and AEF occurs the resulting electric field (REF). The REF is distributed along a straight line perpendicular to the contact surface, so that its intensity (and potential) has a minimum value on the metal surface and the maximum value at a great distance from the metal surface deep into the SCR. Under the influence of AEF as a sided force the metal becomes negative pole and semiconductor - positive pole, therefore, SC with AEF becomes an alternative current source (ACS). The Ni-nSi SC with different diameters (20-1000 μm) under the influence of the AEF as sided force have become ACS with electromotive force in the order of 0.1-1.0 mV, which are generated the electric current in the range of 10-9-10-7 A, flowing through the external resistance 1000 Ohm.

  12. Effect of chemical heterogeneity of biodegradable polymers on surface energy: A static contact angle analysis of polyester model films

    Energy Technology Data Exchange (ETDEWEB)

    Belibel, R.; Avramoglou, T. [INSERM U1148, Laboratory for Vascular Translational Science (LVTS), Institut Galilée, Université Paris 13, Sorbonne Paris Cité, 99 Avenue Jean-Baptiste Clément, Villetaneuse F-93430 (France); Garcia, A. [CNRS UPR 3407, Laboratoire des Sciences des Procédés et des Matériau, Institut Galilée, Université Paris 13, Sorbonne Paris Cité, 99 Avenue Jean-Baptiste Clément, Villetaneuse F-93430 (France); Barbaud, C. [INSERM U1148, Laboratory for Vascular Translational Science (LVTS), Institut Galilée, Université Paris 13, Sorbonne Paris Cité, 99 Avenue Jean-Baptiste Clément, Villetaneuse F-93430 (France); Mora, L., E-mail: Laurence.mora@univ-paris13.fr [INSERM U1148, Laboratory for Vascular Translational Science (LVTS), Institut Galilée, Université Paris 13, Sorbonne Paris Cité, 99 Avenue Jean-Baptiste Clément, Villetaneuse F-93430 (France)

    2016-02-01

    Biodegradable and bioassimilable poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) derivatives were synthesized and characterized in order to develop a new coating for coronary endoprosthesis enabling the reduction of restenosis. The PDMMLA was chemically modified to form different custom groups in its side chain. Three side groups were chosen: the hexyl group for its hydrophobic nature, the carboxylic acid and alcohol groups for their acid and neutral hydrophilic character, respectively. The sessile drop method was applied to characterize the wettability of biodegradable polymer film coatings. Surface energy and components were calculated. The van Oss approach helped reach not only the dispersive and polar acid–base components of surface energy but also acid and basic components. Surface topography was quantified by atomic force microscopy (AFM) and subnanometer average values of roughness (Ra) were obtained for all the analyzed surfaces. Thus, roughness was considered to have a negligible effect on wettability measurements. In contrast, heterogeneous surfaces had to be corrected by the Cassie–Baxter equation for copolymers (10/90, 20/80 and 30/70). The impact of this correction was quantified for all the wettability parameters. Very high relative corrections (%) were found, reaching 100% for energies and 30% for contact angles. - Highlights: • We develop different polymers with various chemical compositions. • Wettability properties were calculated using Cassie corrected contact angles. • Percentage of acid groups in polymers is directly correlated to acid part of SFE. • Cassie corrections are necessary for heterogeneous polymers.

  13. Effect of chemical heterogeneity of biodegradable polymers on surface energy: A static contact angle analysis of polyester model films

    International Nuclear Information System (INIS)

    Belibel, R.; Avramoglou, T.; Garcia, A.; Barbaud, C.; Mora, L.

    2016-01-01

    Biodegradable and bioassimilable poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) derivatives were synthesized and characterized in order to develop a new coating for coronary endoprosthesis enabling the reduction of restenosis. The PDMMLA was chemically modified to form different custom groups in its side chain. Three side groups were chosen: the hexyl group for its hydrophobic nature, the carboxylic acid and alcohol groups for their acid and neutral hydrophilic character, respectively. The sessile drop method was applied to characterize the wettability of biodegradable polymer film coatings. Surface energy and components were calculated. The van Oss approach helped reach not only the dispersive and polar acid–base components of surface energy but also acid and basic components. Surface topography was quantified by atomic force microscopy (AFM) and subnanometer average values of roughness (Ra) were obtained for all the analyzed surfaces. Thus, roughness was considered to have a negligible effect on wettability measurements. In contrast, heterogeneous surfaces had to be corrected by the Cassie–Baxter equation for copolymers (10/90, 20/80 and 30/70). The impact of this correction was quantified for all the wettability parameters. Very high relative corrections (%) were found, reaching 100% for energies and 30% for contact angles. - Highlights: • We develop different polymers with various chemical compositions. • Wettability properties were calculated using Cassie corrected contact angles. • Percentage of acid groups in polymers is directly correlated to acid part of SFE. • Cassie corrections are necessary for heterogeneous polymers.

  14. Recovery of flue gas energy in heat integrated IGCC power plants using the contact economizer system

    CSIR Research Space (South Africa)

    Madzivhandila, V

    2010-10-01

    Full Text Available Asia Pacific Confederation of APCChE 2010 Chemical Engineering Congress October 5-8, 2010, Taipei � �� Recovery of flue gas energy in heat integrated IGCC power plants using the contact economizer system Vhutshilo Madzivhandilaa, Thokozani... temperature and the thermal efficiency of the plant. The 13th Asia Pacific Confederation of APCChE 2010 Chemical Engineering Congress October 5-8, 2010, Taipei � �� 1. Introduction The IGCC (Integrated Gasification Combined Cycle) is one...

  15. On the Challenges of Reducing Contact Resistances in Thermoelectric Generators Based on Half-Heusler Alloys

    DEFF Research Database (Denmark)

    Pham, Hoang Ngan; Van Nong, Ngo; Le, Thanh Hung

    2016-01-01

    -type, respectively. Using this method, the quality of the HH–electrode contacts is improved due to their low electrical contact resistance and less reaction– diffusion layer. The microstructure and chemical composition of the joints were examined using a scanning electron microscope equipped with energydispersive x......-ray analysis. The electrical characteristics of the interfaces at the contacts were studied based on electrical contact resistance and Seebeck scanning microprobe measurements. In this paper, we show that joining the HH to a Ag electrode directly using fast hot pressing resulted in lower contact resistance...

  16. Energy level alignment at planar organic heterojunctions: influence of contact doping and molecular orientation

    Science.gov (United States)

    Opitz, Andreas

    2017-04-01

    Planar organic heterojunctions are widely used in photovoltaic cells, light-emitting diodes, and bilayer field-effect transistors. The energy level alignment in the devices plays an important role in obtaining the aspired gap arrangement. Additionally, the π-orbital overlap between the involved molecules defines e.g. the charge-separation efficiency in solar cells due to charge-transfer effects. To account for both aspects, direct/inverse photoemission spectroscopy and near edge x-ray absorption fine structure spectroscopy were used to determine the energy level landscape and the molecular orientation at prototypical planar organic heterojunctions. The combined experimental approach results in a comprehensive model for the electronic and morphological characteristics of the interface between the two investigated molecular semiconductors. Following an introduction on heterojunctions used in devices and on energy levels of organic materials, the energy level alignment of planar organic heterojunctions will be discussed. The observed energy landscape is always determined by the individual arrangement between the energy levels of the molecules and the work function of the electrode. This might result in contact doping due to Fermi level pinning at the electrode for donor/acceptor heterojunctions, which also improves the solar cell efficiency. This pinning behaviour can be observed across an unpinned interlayer and results in charge accumulation at the donor/acceptor interface, depending on the transport levels of the respective organic semiconductors. Moreover, molecular orientation will affect the energy levels because of the anisotropy in ionisation energy and electron affinity and is influenced by the structural compatibility of the involved molecules at the heterojunction. High structural compatibility leads to π-orbital stacking between different molecules at a heterojunction, which is of additional interest for photovoltaic active interfaces and for ground

  17. Energy Data Base

    Energy Technology Data Exchange (ETDEWEB)

    Kane, L S; Cutler, D E [eds.

    1990-09-01

    To aid in the processing of bibliographic citations (including cataloging information, subject content indicators and abstracts), data are encoded in a format specific to OSTI. This format allows for computer storage, manipulation, and retrieval using both online and offline systems. Expansion of OSTI's data files to include nonnuclear information is relatively recent, beginning in 1974. OSTI's selection and announcement of technical information now represents a broad spectrum of energy-related fields following current research and development interest in both the domestic and the international arenas. To make the database as comprehensive as possible, current as well as background information is included. As part of its responsibility to build and maintain this database, OSTI accepts data on magnetic tape and floppy diskettes; OSTI's responsibility also includes dissemination of this technical information on magnetic tape as well. Each outgoing tape represents a two-week period of input to the database and may vary from 5000 to 14,000 records per tape. These tapes or diskettes, their format, and data content are described in this document.

  18. ULTRACOATINGS: Enabling Energy and Power Solutions in High Contact Stress Environments through Next-Generation Nanocoatings

    Energy Technology Data Exchange (ETDEWEB)

    Blau, P.; Qu, J.; Higdon, C. III (Eaton Corp.)

    2011-09-30

    This industry-driven project was the result of a successful response by Eaton Corporation to a DOE/ITP Program, Grand Challenge, industry call. It consisted of a one-year effort in which ORNL participated in the area of friction and wear testing. In addition to Eaton Corporation and ORNL (CRADA), the project team included: Ames Laboratory, who developed the underlying concept for titanium- zirconium-boron (TZB) based nanocomposite coatings; Borg-Warner Morse TEC, an automotive engine timing chain manufacturer in Ithaca, New York, with its own proprietary hard coating; and Pratt & Whitney Rocketdyne, Inc., a dry-solids pump manufacturer in San Fernando Valley, California. This report focuses only on the portion of work that was conducted by ORNL, in a CRADA with Eaton Corporation. A comprehensive final report for the entire effort, which ended in September 2010, has been prepared for DOE by the team. The term 'ultracoatings' derives from the ambitious technical target for the new generation of nanocoatings. As applications, Eaton was specifically considering a fuel pump and a gear application in which the product of the contact pressure and slip velocity during operation of mating surfaces, commonly called the 'PV value', was equal to or greater than 70,000 MPa-m/s. This ambitious target challenges the developers of coatings to produce material capable of strong bonding to the substrate, as well as high wear resistance and the ability to maintain sliding friction at low, energy-saving levels. The partners in this effort were responsible for the selection and preparation of such candidate ultracoatings, and ORNL used established tribology testing capabilities to help screen these candidates for performance. This final report summarizes ORNL's portion of the nanocomposite coatings development effort and presents both generated data and the analyses that were used in the course of this effort. Initial contact stress and speed calculations

  19. Diagnosis of Constant Faults in Read-Once Contact Networks over Finite Bases using Decision Trees

    KAUST Repository

    Busbait, Monther I.

    2014-05-01

    We study the depth of decision trees for diagnosis of constant faults in read-once contact networks over finite bases. This includes diagnosis of 0-1 faults, 0 faults and 1 faults. For any finite basis, we prove a linear upper bound on the minimum depth of decision tree for diagnosis of constant faults depending on the number of edges in a contact network over that basis. Also, we obtain asymptotic bounds on the depth of decision trees for diagnosis of each type of constant faults depending on the number of edges in contact networks in the worst case per basis. We study the set of indecomposable contact networks with up to 10 edges and obtain sharp coefficients for the linear upper bound for diagnosis of constant faults in contact networks over bases of these indecomposable contact networks. We use a set of algorithms, including one that we create, to obtain the sharp coefficients.

  20. Relationship between wettability and lubrication characteristics of the surfaces of contacting phospholipid-based membranes.

    Science.gov (United States)

    Pawlak, Zenon; Petelska, Aneta D; Urbaniak, Wieslaw; Yusuf, Kehinde Q; Oloyede, Adekunle

    2013-04-01

    The wettability of the articular surface of cartilage depends on the condition of its surface active phospholipid overlay, which is structured as multi-bilayer. Based on a hypothesis that the surface of cartilage facilitates the almost frictionless lubrication of the joint, we examined the characteristics of this membrane surface entity in both its normal and degenerated conditions using a combination of atomic force microscopy, contact angle measurement, and friction test methods. The observations have led to the conclusions that (1) the acid-base equilibrium condition influences the lubrication effectiveness of the surface of cartilage and (2) the friction coefficient is significantly dependent on the hydrophobicity of the surface of the tissue, thereby confirming the hypothesis tested in this paper. Both wettability angle and interfacial energy were obtained for varying conditions of the cartilage surface both in its wet, dry and lipid-depleted conditions. The interfacial energy also increased with mole fraction of the lipid species reaching an asymptotic value after 0.6. Also, the friction coefficient was found to decrease to an asymptotic level as the wettability angle increased. The result reveal that the interfacial energy increased with pH till pH = 4.0, and then decreased from pH = 4.0 to reach equilibrium at pH = 7.0.

  1. NANOCOMPOSITE POWDERS FOR NEW CONTACT MATERIALS BASED ONCOPPER AND ALUMINA

    Directory of Open Access Journals (Sweden)

    Marija Korać

    2008-11-01

    Full Text Available This paper is a contribution to characterization of Cu-Al2O3 powders with nanostructure designed for the production of dispersion strengthened contact materials. New materials with predetermined properties can be successfully synthesized by utilizing the principles of hydrometallurgy and powder metallurgy. The results show a development of a new procedure for the synthesis. The applied characterization methods were differential thermal and thermogravimetric analysis (DTA-TGA, X-ray diffraction (XRD, scanning electron microscopy (SEM, Transmission Electron Microscopy (TEM: Focused Ion Beam (FIB and Analytical Electron Microscopy (AEM. Nanostructure characteristics, particle size in range 20-50 nm, and uniform distribution of dispersoide in copper matrix were validated.

  2. Screenable silver and base metal solar cell contacts

    Science.gov (United States)

    Ross, B.

    1980-01-01

    The metallurgical soundness of the all-metal screenable thick film electrode system is established for silver and copper electrodes. Silver fluoride was identified as a successful etchant material and is found most effective in the liquid phase (435-460 C). Best results were achieved with the eutectic alloys of dopants and semiconductors. The air-fired silver inks were strongly adherent, rugged, and solderable, whereas the hydrogen-fired silver inks had very poor adhesion. A two-step firing process was devised in which copper inks containing silver fluoride were activated in a nitrogen atmosphere, with sintering done at the same or higher temperatures in hydrogen. Good solar cells were made using the copper paste back contacts demonstrating that the electrodes are not the limiting factors in efficiency.

  3. Workshop on Direct Contact Heat Transfer at the Solar Energy Research Institute

    CERN Document Server

    Boehm, R

    1988-01-01

    to increase the use of direct contact processes, the National Science Foundation sup­ ported a workshop on direct contact heat transfer at the Solar Energy Research Insti­ tute in the summer of 1985. We served as organizers for this workshop, which em­ phasized an area of thermal engineering that, in our opinion, has great promise for the future, but has not yet reached the point of wide-spread commercial application. Hence, a summary of the state of knowledge at this point is timely. The workshop had a dual objective: 1. To summarize the current state of knowledge in such a form that industrial practi­ tioners can make use of the available information. 2. To indicate the research and development needed to advance the state-of-the-art, indicating not only what kind of research is needed, but also the industrial poten­ tial that could be realized if the information to be obtained through the proposed research activities were available.

  4. The influence of friction coefficient and wheel/rail profiles on energy dissipation in the wheel/rail contact

    NARCIS (Netherlands)

    Idarraga Alarcon, G.A.; Burgelman, N.D.M.; Meza Meza, J.; Toro, A.; Li, Z.

    2015-01-01

    This work investigates the energy dissipation in a wheel/rail system through friction work modeling. In order to identify the effect of the friction coefficient on the energy dissipation in the wheel/rail contact, several simulations were performed using a 3D multibody model of a railway vehicle

  5. Advanced fibre based energy storage.

    OpenAIRE

    Reid, Daniel

    2017-01-01

    New energy storage devices are required to enable future technologies. With the rise of wearable consumer and medical devices, a suitable flexible and wearable means of storing electrical energy is required. Fibre-based devices present a possible method of achieving this aim. Fibres are inherently more flexible than their bulk counterparts, and as such can be employed to form the electrodes of flexible batteries and capacitors. They also present a facile possibility for incorporation into man...

  6. Graphene-based energy devices

    CERN Document Server

    Yusoff, A Rashid bin Mohd

    2015-01-01

    This first book dedicated to the topic provides an up-to-date account of the many opportunities graphene offers for robust, workable energy generation and storage devices. Following a brief overview of the fundamentals of graphene, including the main synthesis techniques, characterization methods and properties, the first part goes on to deal with graphene for energy storage applications, such as lithium-ion batteries, supercapacitors and hydrogen storage. The second part is concerned with graphene-based energy-generation devices, in particular conventional as well as microbial and enzymatic f

  7. Three-dimensional contact analysis of coupled surfaces by a novel contact transformation method based on localized Lagrange multipliers

    Directory of Open Access Journals (Sweden)

    Yi-Tsung Lin

    2016-04-01

    Full Text Available Instead of obsessively emphasizing to reduce the number of time increments and reshape the models, a novel surface contact transformation to increase efficiency is presented in this study. Wear on the bearing surfaces was investigated following the coupled regions from the pressure distribution, computed by means of three-dimensional finite element method models; an approximate analytical model and formulation in three-dimensional frictional contact problems based on modified localized Lagrange multiplier method have also been developed and discussed. Understanding wear behavior patterns in mechanical components is a significant task in engineering design. The proposed approach provides a complete and effective solution to the wear problem in a quasi-dynamic manner. However, expensive computing time is needed in the incremental procedures. In this article, an alternative and efficient finite element approach is introduced to reduce the computation costs of wear prediction. Through the successful verification of wear depth and volume loss of the pin-on-plate, block-on-ring, and metal-on-plastic artificial hip joint wear behaviors, the numerical calculations are shown to be both valid and feasible. Furthermore, the results also show that the central processing unit time required by the proposed method is nearly half that of the previous methods without loss of accuracy.

  8. Radiation effects on ohmic and Schottky contacts based on 4H and 6H-SiC

    International Nuclear Information System (INIS)

    Cinar, Kuebra; Coskun, Cevdet; Guer, Emre; Aydogan, Sakir

    2009-01-01

    A systematic study of Ni based ohmic and Schottky contacts (SCs) onto the n-4H-SiC and n-6H-SiC under relatively low-dose (1 x 10 12 e - cm -2 ) and high-energy (6, 12, 15 MeV) electron irradiation (HEEI) has been introduced. Lower specific contact resistivity has been reached for Ni based ohmic contact structures on both 4H and 6H-SiC after each electron irradiation. This finding has been explained by the displacement damage produced by the collision of electrons with atoms of Ni contact material. It has been observed that the HEEI caused to increase in the ideality factors of both SCs indicating deviation from thermionic emission theory in current transport mechanism. While the Schottky barrier height (SBH) for Ni/4H-SiC SC remains nearly constant, an increase has been observed for the Ni/6H-SiC SC. Donor concentrations for both diodes have decreased with increasing electron energy probably due to the trapping effect of the irradiation induced defect(s).

  9. Radiation effects on ohmic and Schottky contacts based on 4H and 6H-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Cinar, Kuebra [Department of Physics, Faculty of Sciences and Arts, Atatuerk University, 25240 Erzurum (Turkey); Coskun, Cevdet [Department of Physics, Faculty of Sciences and Arts, Atatuerk University, 25240 Erzurum (Turkey)], E-mail: ccoskun@atauni.edu.tr; Guer, Emre; Aydogan, Sakir [Department of Physics, Faculty of Sciences and Arts, Atatuerk University, 25240 Erzurum (Turkey)

    2009-01-15

    A systematic study of Ni based ohmic and Schottky contacts (SCs) onto the n-4H-SiC and n-6H-SiC under relatively low-dose (1 x 10{sup 12} e{sup -} cm{sup -2}) and high-energy (6, 12, 15 MeV) electron irradiation (HEEI) has been introduced. Lower specific contact resistivity has been reached for Ni based ohmic contact structures on both 4H and 6H-SiC after each electron irradiation. This finding has been explained by the displacement damage produced by the collision of electrons with atoms of Ni contact material. It has been observed that the HEEI caused to increase in the ideality factors of both SCs indicating deviation from thermionic emission theory in current transport mechanism. While the Schottky barrier height (SBH) for Ni/4H-SiC SC remains nearly constant, an increase has been observed for the Ni/6H-SiC SC. Donor concentrations for both diodes have decreased with increasing electron energy probably due to the trapping effect of the irradiation induced defect(s)

  10. Prediction of static friction coefficient in rough contacts based on the junction growth theory

    Science.gov (United States)

    Spinu, S.; Cerlinca, D.

    2017-08-01

    The classic approach to the slip-stick contact is based on the framework advanced by Mindlin, in which localized slip occurs on the contact area when the local shear traction exceeds the product between the local pressure and the static friction coefficient. This assumption may be too conservative in the case of high tractions arising at the asperities tips in the contact of rough surfaces, because the shear traction may be allowed to exceed the shear strength of the softer material. Consequently, the classic frictional contact model is modified in this paper so that gross sliding occurs when the junctions formed between all contacting asperities are independently sheared. In this framework, when the contact tractions, normal and shear, exceed the hardness of the softer material on the entire contact area, the material of the asperities yields and the junction growth process ends in all contact regions, leading to gross sliding inception. This friction mechanism is implemented in a previously proposed numerical model for the Cattaneo-Mindlin slip-stick contact problem, which is modified to accommodate the junction growth theory. The frictionless normal contact problem is solved first, then the tangential force is gradually increased, until gross sliding inception. The contact problems in the normal and in the tangential direction are successively solved, until one is stabilized in relation to the other. The maximum tangential force leading to a non-vanishing stick area is the static friction force that can be sustained by the rough contact. The static friction coefficient is eventually derived as the ratio between the latter friction force and the normal force.

  11. Resonant tunneling diodes as energy-selective contacts used in hot-carrier solar cells

    International Nuclear Information System (INIS)

    Takeda, Yasuhiko; Sugimoto, Noriaki; Ichiki, Akihisa; Kusano, Yuya; Motohiro, Tomoyoshi

    2015-01-01

    Among the four features unique to hot-carrier solar cells (HC-SCs): (i) carrier thermalization time and (ii) carrier equilibration time in the absorber, (iii) energy-selection width and (iv) conductance of the energy-selective contacts (ESCs), requisites of (i)-(iii) for high conversion efficiency have been clarified. We have tackled the remaining issues related to (iv) in the present study. The detailed balance model of HC-SC operation has been improved to involve a finite value of the ESC conductance to find the required values, which in turn has been revealed to be feasible using resonant tunneling diodes (RTDs) consisting of semiconductor quantum dots (QDs) and quantum wells (QWs) by means of a formulation to calculate the conductance of the QD- and QW-RTDs derived using the rigorous solutions of the effective-mass Hamiltonians. Thus, all of the four requisites unique to HC-SCs to achieve high conversion efficiency have been elucidated, and the two requisites related to the ESCs can be fulfilled using the QD- and QW-RTDs

  12. Optimization of Contact Force and Pull-in Voltage for Series based MEMS Switch

    Directory of Open Access Journals (Sweden)

    Abhijeet KSHIRSAGAR

    2010-04-01

    Full Text Available Cantilever based metal-to-metal contact type MEMS series switch has many applications namely in RF MEMS, Power MEMS etc. A typical MEMS switch consists of a cantilever as actuating element to make the contact between the two metal terminals of the switch. The cantilever is pulled down by applying a pull-in voltage to the control electrode that is located below the middle portion of the cantilever while only the tip portion of the cantilever makes contact between the two terminals. Detailed analysis of bending of the cantilever for different pull-in voltages reveals some interesting facts. At low pull-in voltage the cantilever tip barely touches the two terminals, thus resulting in very less contact area. To increase contact area a very high pull-in voltage is applied, but it lifts the tip from the free end due to concave curving of the cantilever in the middle region of the cantilever where the electrode is located. Again it results in less contact area. Furthermore, the high pull-in voltage produces large stress at the base of the cantilever close to the anchor. Therefore, an optimum, pull-in voltage must exist at which the concave curving is eliminated and contact area is maximum. In this paper authors report the finding of optimum contact force and pull-in voltage.

  13. Effect of chemical heterogeneity of biodegradable polymers on surface energy: A static contact angle analysis of polyester model films.

    Science.gov (United States)

    Belibel, R; Avramoglou, T; Garcia, A; Barbaud, C; Mora, L

    2016-02-01

    Biodegradable and bioassimilable poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) derivatives were synthesized and characterized in order to develop a new coating for coronary endoprosthesis enabling the reduction of restenosis. The PDMMLA was chemically modified to form different custom groups in its side chain. Three side groups were chosen: the hexyl group for its hydrophobic nature, the carboxylic acid and alcohol groups for their acid and neutral hydrophilic character, respectively. The sessile drop method was applied to characterize the wettability of biodegradable polymer film coatings. Surface energy and components were calculated. The van Oss approach helped reach not only the dispersive and polar acid-base components of surface energy but also acid and basic components. Surface topography was quantified by atomic force microscopy (AFM) and subnanometer average values of roughness (Ra) were obtained for all the analyzed surfaces. Thus, roughness was considered to have a negligible effect on wettability measurements. In contrast, heterogeneous surfaces had to be corrected by the Cassie-Baxter equation for copolymers (10/90, 20/80 and 30/70). The impact of this correction was quantified for all the wettability parameters. Very high relative corrections (%) were found, reaching 100% for energies and 30% for contact angles. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Contact effects analyzed by a parameter extraction method based on a single bottom-gate/top-contact organic thin-film transistor

    Science.gov (United States)

    Takagaki, Shunsuke; Yamada, Hirofumi; Noda, Kei

    2018-03-01

    Contact effects in organic thin-film transistors (OTFTs) were examined by using our previously proposed parameter extraction method from the electrical characteristics of a single staggered-type device. Gate-voltage-dependent contact resistance and channel mobility in the linear regime were evaluated for bottom-gate/top-contact (BGTC) pentacene TFTs with active layers of different thicknesses, and for pentacene TFTs with contact-doped layers prepared by coevaporation of pentacene and tetrafluorotetracyanoquinodimethane (F4TCNQ). The extracted parameters suggested that the influence of the contact resistance becomes more prominent with the larger active-layer thickness, and that contact-doping experiments give rise to a drastic decrease in the contact resistance and a concurrent considerable improvement in the channel mobility. Additionally, the estimated energy distributions of trap density in the transistor channel probably reflect the trap filling with charge carriers injected into the channel regions. The analysis results in this study confirm the effectiveness of our proposed method, with which we can investigate contact effects and circumvent the influences of characteristic variations in OTFT fabrication.

  15. Prioritized Contact Transport Stream

    Science.gov (United States)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  16. Energy data base: subject thesaurus

    International Nuclear Information System (INIS)

    Redford, J.S.

    1981-10-01

    The technical staff of the DOE Technical Information Center, during its subject indexing activities, develops and structures a vocabulary that allows consistent machine storage and retrieval of information necessary to the accomplishment of the DOE mission. This thesaurus incorporates that structured vocabulary. The terminology of this thesaurus is used for the subject control of information announced in DOE Energy Research Abstracts, Energy Abstracts for Policy Analysis, and various update journals and bulletins in specialized areas. This terminology also facilitates subject searching of the DOE Energy Data Base on the DOE/RECON on-line retrieval system and on other commercial retrieval systems. The rapid expansion of the DOE's activities will result in a commitant thesaurus expansion as information relating to new activities is indexed. Only the terms used in the indexing of documents at the Technical Information Center to date are included

  17. Nanoscale contacts to organic molecules based on layered semiconductor substrates

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, Sebastian

    2009-06-15

    This work reports on the integration of organic molecules as nanoelectronic device units on semiconductor substrates. Two novel preparation methods for sub-10-nm separated metal electrodes are presented using current microelectronics process technology. The first method utilises AlGaAs/GaAs heterostructures grown by molecular beam epitaxy (MBE) as mold to create planar metal electrodes employing a newly developed, high resolution nanotransfer printing (nTP) process. The second method uses commercially available Silicon-on-Insulator (SOI) substrates as base material for the fabrication of nanogap electrode devices. This sandwich-like material stack consists of a silicon substrate, a thin silicon oxide layer, and a capping silicon layer on top. Electronic transport measurements verified their excellent electrical properties at liquid helium temperatures. Specifically tailored nanogap devices featured an electrode insulation in the GW range even up to room temperature as well as within aqueous electrolyte solution. Finally, the well defined layer architecture facilitated the fabrication of electrodes with gap separations below-10-nm to be directly bridged by molecules. Approximately 12-nm-long conjugated molecules with extended -electron system were assembled onto the devices from solution. A large conductance gap was observed with a steep increase in current at a bias voltage of V{sub T}{approx}{+-}1.5 V. Theoretical calculations based on density functional theory and non-equilibrium Green's function formalism confirmed the measured non-linear IV-characteristics qualitatively and lead to the conclusion that the conductance gap mainly originates from the oxygen containing linker. Temperature dependent investigations of the conductance indicated a hopping charge transport mechanism through the central part of the molecule for bias voltages near but below V{sub T}. (orig.)

  18. Definition and detection of contact in atomistic simulations

    NARCIS (Netherlands)

    Solhjoo, Soheil; Vakis, Antonis I.

    2015-01-01

    In atomistic simulations, contact depends on the accurate detection of contacting atoms as well as their contact area. While it is common to define contact between atoms based on the so-called ‘contact distance’ where the interatomic potential energy reaches its minimum, this discounts, for example,

  19. Energy conserving schemes for the simulation of musical instrument contact dynamics

    Science.gov (United States)

    Chatziioannou, Vasileios; van Walstijn, Maarten

    2015-03-01

    Collisions are an innate part of the function of many musical instruments. Due to the nonlinear nature of contact forces, special care has to be taken in the construction of numerical schemes for simulation and sound synthesis. Finite difference schemes and other time-stepping algorithms used for musical instrument modelling purposes are normally arrived at by discretising a Newtonian description of the system. However because impact forces are non-analytic functions of the phase space variables, algorithm stability can rarely be established this way. This paper presents a systematic approach to deriving energy conserving schemes for frictionless impact modelling. The proposed numerical formulations follow from discretising Hamilton's equations of motion, generally leading to an implicit system of nonlinear equations that can be solved with Newton's method. The approach is first outlined for point mass collisions and then extended to distributed settings, such as vibrating strings and beams colliding with rigid obstacles. Stability and other relevant properties of the proposed approach are discussed and further demonstrated with simulation examples. The methodology is exemplified through a case study on tanpura string vibration, with the results confirming the main findings of previous studies on the role of the bridge in sound generation with this type of string instrument.

  20. Study effective factors on customer compliance in high contact services based on Bandura social - Cognitive theory

    OpenAIRE

    zahra asadi; bahman hajipour

    2014-01-01

    In today's competitive world, all market participants ranging from individuals, organizations should be looking for ways to success in the market. The secret to success high contact service providers as important part of market participants is, compliance and follow customers of high contact service providers the instructions and guidance. In this paper, a model based on Bandura social - Cognitive theory has Provided to customer compliance . According Bandura social - Cognitive theory and t...

  1. Micromotor-based energy generation.

    Science.gov (United States)

    Singh, Virendra V; Soto, Fernando; Kaufmann, Kevin; Wang, Joseph

    2015-06-01

    A micromotor-based strategy for energy generation, utilizing the conversion of liquid-phase hydrogen to usable hydrogen gas (H2), is described. The new motion-based H2-generation concept relies on the movement of Pt-black/Ti Janus microparticle motors in a solution of sodium borohydride (NaBH4) fuel. This is the first report of using NaBH4 for powering micromotors. The autonomous motion of these catalytic micromotors, as well as their bubble generation, leads to enhanced mixing and transport of NaBH4 towards the Pt-black catalytic surface (compared to static microparticles or films), and hence to a substantially faster rate of H2 production. The practical utility of these micromotors is illustrated by powering a hydrogen-oxygen fuel cell car by an on-board motion-based hydrogen and oxygen generation. The new micromotor approach paves the way for the development of efficient on-site energy generation for powering external devices or meeting growing demands on the energy grid. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Role of Metal Contacts in High-Performance Phototransistors Based on WSe 2 Monolayers

    KAUST Repository

    Zhang, Wenjing

    2014-08-26

    Phototransistors based on monolayer transition metal dichalcogenides (TMD) have high photosensitivity due to their direct band gap transition. However, there is a lack of understanding of the effect of metal contacts on the performance of atomically thin TMD phototransistors. Here, we fabricate phototransistors based on large-area chemical vapor deposition (CVD) tungsten diselenide (WSe2) monolayers contacted with the metals of different work function values. We found that the low Schottky-contact WSe2 phototransistors exhibit a very high photo gain (105) and specific detectivity (1014Jones), values higher than commercial Si- and InGaAs-based photodetectors; however, the response speed is longer than 5 s in ambient air. In contrast, the high Schottky-contact phototransistors display a fast response time shorter than 23 ms, but the photo gain and specific detectivity decrease by several orders of magnitude. Moreover, the fast response speed of the high Schottky-contact devices is maintained for a few months in ambient air. This study demonstrates that the contact plays an important role in TMD phototransistors, and barrier height tuning is critical for optimizing the photoresponse and photoresponsivity. © 2014 American Chemical Society.

  3. Development of an IMU-based foot-ground contact detection (FGCD) algorithm.

    Science.gov (United States)

    Kim, Myeongkyu; Lee, Donghun

    2017-03-01

    It is well known that, to locate humans in GPS-denied environments, a lower limb kinematic solution based on Inertial Measurement Unit (IMU), force plate, and pressure insoles is essential. The force plate and pressure insole are used to detect foot-ground contacts. However, the use of multiple sensors is not desirable in most cases. This paper documents the development of an IMU-based FGCD (foot-ground contact detection) algorithm considering the variations of both walking terrain and speed. All IMU outputs showing significant changes on the moments of foot-ground contact phases are fully identified through experiments in five walking terrains. For the experiment on each walking terrain, variations of walking speeds are also examined to confirm the correlations between walking speed and the main parameters in the FGCD algorithm. As experimental results, FGCD algorithm successfully detecting four contact phases is developed, and validation of performance of the FGCD algorithm is also implemented. Practitioner Summary: In this research, it was demonstrated that the four contact phases of Heel strike (or Toe strike), Full contact, Heel off and Toe off can be independently detected regardless of the walking speed and walking terrain based on the detection criteria composed of the ranges and the rates of change of the main parameters measured from the Inertial Measurement Unit sensors.

  4. Analysis of direct contact membrane distillation based on a lumped-parameter dynamic predictive model

    KAUST Repository

    Karam, Ayman M.

    2016-10-03

    Membrane distillation (MD) is an emerging technology that has a great potential for sustainable water desalination. In order to pave the way for successful commercialization of MD-based water desalination techniques, adequate and accurate dynamical models of the process are essential. This paper presents the predictive capabilities of a lumped-parameter dynamic model for direct contact membrane distillation (DCMD) and discusses the results under wide range of steady-state and dynamic conditions. Unlike previous studies, the proposed model captures the time response of the spacial temperature distribution along the flow direction. It also directly solves for the local temperatures at the membrane interfaces, which allows to accurately model and calculate local flux values along with other intrinsic variables of great influence on the process, like the temperature polarization coefficient (TPC). The proposed model is based on energy and mass conservation principles and analogy between thermal and electrical systems. Experimental data was collected to validated the steady-state and dynamic responses of the model. The obtained results shows great agreement with the experimental data. The paper discusses the results of several simulations under various conditions to optimize the DCMD process efficiency and analyze its response. This demonstrates some potential applications of the proposed model to carry out scale up and design studies. © 2016

  5. In vivo patellofemoral contact mechanics during active extension using a novel dynamic MRI-based methodology.

    Science.gov (United States)

    Borotikar, B S; Sheehan, F T

    2013-12-01

    To establish an in vivo, normative patellofemoral (PF) cartilage contact mechanics database acquired during voluntary muscle control using a novel, dynamic, magnetic resonance (MR) imaging-based, computational methodology and validate the contact mechanics sensitivity to the known sub-millimeter methodological accuracies. Dynamic cine phase-contrast and multi-plane cine (MPC) images were acquired while female subjects (n = 20, sample of convenience) performed an open kinetic chain (knee flexion-extension) exercise inside a 3-T MR scanner. Static cartilage models were created from high resolution three-dimensional static MR data and accurately placed in their dynamic pose at each time frame based on the cine-PC (CPC) data. Cartilage contact parameters were calculated based on the surface overlap. Statistical analysis was performed using paired t-test and a one-sample repeated measures ANOVA. The sensitivity of the contact parameters to the known errors in the PF kinematics was determined. Peak mean PF contact area was 228.7 ± 173.6 mm(2) at 40° knee angle. During extension, contact centroid and peak strain locations tracked medially on the femoral and patellar cartilage and were not significantly different from each other. At 25°, 30°, 35°, and 40° of knee extension, contact area was significantly different. Contact area and centroid locations were insensitive to rotational and translational perturbations. This study is a first step towards unfolding the biomechanical pathways to anterior PF pain and osteoarthritis (OA) using dynamic, in vivo, and accurate methodologies. The database provides crucial data for future studies and for validation of, or as an input to, computational models. Published by Elsevier Ltd.

  6. Novel Sn-based Contact Structure for GeTe Phase Change Materials.

    Science.gov (United States)

    Simchi, Hamed; Cooley, Kayla A; Ding, Zelong; Molina, Alex; Mohney, Suzanne E

    2018-04-18

    Germanium telluride (GeTe) is a phase change material (PCM) that has gained recent attention due to its incorporation as an active material for radio frequency (RF) switches, as well as memory and novel optoelectronic devices. Considering PCM-based RF switches, parasitic resistances from Ohmic contacts can be a limiting factor in device performance. Reduction of the contact resistance (Rc) is therefore critical for reducing the ON-state resistance in order to meet the requirements of high-frequency RF applications. To engineer the Schottky barrier between the metal contact and GeTe, Sn was tested as an interesting candidate to alter the composition of the semiconductor near its surface, potentially forming narrow bandgap (0.2 eV) SnTe or a graded alloy with SnTe in GeTe. For this purpose, a novel contact stack of Sn/Fe/Au was employed and compared to a conventional Ti/Pt/Au stack. Two different pre-metallization surface treatments of HCl and deionized (DI) H2O were employed to make the Te-rich and Ge-rich interface, respectively. Contact resistance values were extracted using the refined transfer length method (RTLM). The best results were obtained with DI H2O for the Sn-based contacts but HCl treatment for the Ti/Pt/Au contacts. The as-deposited contacts had Rc (ρc) of 0.006 Ω.mm (8 × 10-9 Ω-cm2) for Sn/Fe/Au and 0.010 Ω.mm (3 × 10-8 Ω-cm2) for Ti/Pt/Au. However, the Sn/Fe/Au contacts were stable and their resistance decreased further to 0.004 Ω.mm (4 × 10-9 Ω-cm2) after annealing at 200 oC. In contrast, the contact resistance of the Ti/Pt/Au stack increased to 0.012 Ω.mm (4 × 10-8 Ω-cm2). Transmission electron microscopy (TEM) was used to characterize the interfacial reactions between the metals and GeTe. It was found that formation of SnTe at the interface, in addition to Fe-diffusion (doping) into GeTe, are likely responsible for the superior performance of Sn/Fe/Au contacts, resulting in the lowest reported contact resistance on GeTe.

  7. Prevalence of non-contact and contact childhood sexual abuse: An Internet-based sample of men who have sex with men in China.

    Directory of Open Access Journals (Sweden)

    Wenjian Xu

    Full Text Available The prevalence of childhood sexual abuse (CSA is high among Western men who have sex with men (MSM, and CSA is associated with certain socio-demographic variables and with human immunodeficiency virus (HIV status. Little is known about CSA among Chinese MSM; therefore, we explored the prevalence and frequency of non-contact (e.g., sexual invitations, exhibitionism and contact (e.g., intercourse, genital contact forms of CSA in an Internet-based sample of MSM in China. We also examined the associations between the participants' socio-demographic characteristics and HIV status, and their histories of CSA.We surveyed MSM from 30 Chinese provinces in 2014-2015; 1,030 (mean age = 25.15 years, SD = 6.32 and 1,020 (mean age = 25.05 years, SD = 5.95 respondents were eligible for inclusion in the non-contact and contact CSA groups, respectively.Prevalence of non-contact and contact CSA was 36.2% and 29.8%, respectively; 20.4% and 15.0% had experienced non-contact and contact CSA ≥ 3 times, respectively. Most respondents were young adults, well educated, single, had never "come out," and self-identified as gay or bisexual men. Univariate analyses showed that respondents who had experienced contact CSA were more likely to be HIV-positive than those who had never experienced contact CSA. Multivariate analyses showed that non-contact CSA was associated with less education, being in a relationship with a woman or a man, and having "come out." Contact CSA was associated with less education, higher income, and being in a relationship with a man. Respondents who had experienced non-contact CSA ≥ 3 times were more likely to be less educated, "out," and to be in a relationship with a woman or a man. Respondents who had experienced contact CSA ≥ 3 times were more likely to be less educated and to be in a relationship with a man.It is necessary to pay closer attention to CSA among MSM and other sexual minorities in China.

  8. Nanosecond laser scribing of CIGS thin film solar cell based on ITO bottom contact

    Science.gov (United States)

    Kuk, Seungkuk; Wang, Zhen; Fu, Shi; Zhang, Tao; Yu, Yi Yin; Choi, JaeMyung; Jeong, Jeung-hyun; Hwang, David J.

    2018-03-01

    Cu(In,Ga)Se2 (CIGS) thin films, a promising photovoltaic architecture, have mainly relied on Molybdenum for the bottom contact. However, the opaque nature of Molybdenum (Mo) poses limitations in module level fabrication by laser scribing as a preferred method for interconnect. We examined the P1, P2, and P3 laser scribing processes on CIGS photovoltaic architecture on the indium tin oxide (ITO) bottom contact with a cost-effective nanosecond pulsed laser of 532 nm wavelength. Laser illuminated from the substrate side, enabled by the transparent bottom contact, facilitated selective laser energy deposition onto relevant interfaces towards high-quality scribing. Parametric tuning procedures are described in conjunction with experimental and numerical investigation of relevant mechanisms, and preliminary mini-module fabrication results are also presented.

  9. Free energy of contact formation in proteins: Efficient computation in the elastic network approximation

    Science.gov (United States)

    Hamacher, Kay

    2011-07-01

    Biomolecular simulations have become a major tool in understanding biomolecules and their complexes. However, one can typically only investigate a few mutants or scenarios due to the severe computational demands of such simulations, leading to a great interest in method development to overcome this restriction. One way to achieve this is to reduce the complexity of the systems by an approximation of the forces acting upon the constituents of the molecule. The harmonic approximation used in elastic network models simplifies the physical complexity to the most reduced dynamics of these molecular systems. The reduced polymer modeled this way is typically comprised of mass points representing coarse-grained versions of, e.g., amino acids. In this work, we show how the computation of free energy contributions of contacts between two residues within the molecule can be reduced to a simple lookup operation in a precomputable matrix. Being able to compute such contributions is of great importance: protein design or molecular evolution changes introduce perturbations to these pair interactions, so we need to understand their impact. Perturbation to the interactions occurs due to randomized and fixated changes (in molecular evolution) or designed modifications of the protein structures (in bioengineering). These perturbations are modifications in the topology and the strength of the interactions modeled by the elastic network models. We apply the new algorithm to (1) the bovine trypsin inhibitor, a well-known enzyme in biomedicine, and show the connection to folding properties and the hydrophobic collapse hypothesis and (2) the serine proteinase inhibitor CI-2 and show the correlation to Φ values to characterize folding importance. Furthermore, we discuss the computational complexity and show empirical results for the average case, sampled over a library of 77 structurally diverse proteins. We found a relative speedup of up to 10 000-fold for large proteins with respect to

  10. Improving Teacher-Student Contact in a Campus through a Location-Based Mobile Application

    Science.gov (United States)

    Ferreira, Vítor Manuel; Ramos, Fernando

    2014-01-01

    This paper presents a new mobile micro-broadcast (or near-me) Location-Based Service designed to promote face-to-face communication among users located within a given geographical area such as a University campus. Because the communication services provided are time dependent, the application decides whom to contact based on the geographic…

  11. Effectiveness of contact-based education for reducing mental illness-related stigma in pharmacy students

    Directory of Open Access Journals (Sweden)

    Patten Scott B

    2012-12-01

    Full Text Available Abstract Background A strategy for reducing mental illness-related stigma in health-profession students is to include contact-based sessions in their educational curricula. In such sessions students are able to interact socially with a person that has a mental illness. We sought to evaluate the effectiveness of this strategy in a multi-centre study of pharmacy students. Methods The study was a randomized controlled trial conducted at three sites. Because it was necessary that all students receive the contact-based sessions, the students were randomized either to an early or late intervention, with the late intervention group not having participated in the contact-based education at the time when the primary outcome was assessed. The primary outcome, stigma, was assessed using an attitudes scale called the Opening Minds Survey for Health Care Providers (OMS-HC. Results We initially confirmed that outcomes were homogeneous across study centres, centre by group interaction, p = 0.76. The results were pooled across the three study centres. A significant reduction in stigma was observed in association with the contact-based sessions (mean change 4.3 versus 1.5, t=2.1, p=0.04. The effect size (Cohen’s d was 0.45. A similar reduction was seen in the control group when they later received the intervention. Conclusions Contact-based education is an effective method of reducing stigma during pharmacy education. These results add to a growing literature confirming the effectiveness of contact-based strategies for stigma reduction in health profession trainees.

  12. Development of 3D online contact measurement system for intelligent manufacturing based on stereo vision

    Science.gov (United States)

    Li, Peng; Chong, Wenyan; Ma, Yongjun

    2017-10-01

    In order to avoid shortcomings of low efficiency and restricted measuring range exsited in traditional 3D on-line contact measurement method for workpiece size, the development of a novel 3D contact measurement system is introduced, which is designed for intelligent manufacturing based on stereo vision. The developed contact measurement system is characterized with an intergarted use of a handy probe, a binocular stereo vision system, and advanced measurement software.The handy probe consists of six track markers, a touch probe and the associated elcetronics. In the process of contact measurement, the hand probe can be located by the use of the stereo vision system and track markers, and 3D coordinates of a space point on the workpiece can be mearsured by calculating the tip position of a touch probe. With the flexibility of the hand probe, the orientation, range, density of the 3D contact measurenent can be adptable to different needs. Applications of the developed contact measurement system to high-precision measurement and rapid surface digitization are experimentally demonstrated.

  13. A Hydrogel-Based Hybrid Theranostic Contact Lens for Fungal Keratitis.

    Science.gov (United States)

    Huang, Jian-Fei; Zhong, Jing; Chen, Guo-Pu; Lin, Zuan-Tao; Deng, Yuqing; Liu, Yong-Lin; Cao, Piao-Yang; Wang, Bowen; Wei, Yantao; Wu, Tianfu; Yuan, Jin; Jiang, Gang-Biao

    2016-07-26

    Fungal keratitis, a severe ocular disease, is one of the leading causes of ocular morbidity and blindness, yet it is often neglected, especially in developing countries. Therapeutic efficacy of traditional treatment such as eye drops is very limited due to poor bioavailability, whereas intraocular injection might cause serious side effects. Herein, we designed and fabricated a hybrid hydrogel-based contact lens which comprises quaternized chitosan (HTCC), silver nanoparticles, and graphene oxide (GO) with a combination of antibacterial and antifungal functions. The hydrogel is cross-linked through electrostatic interactions between GO and HTCC, resulting in strong mechanical properties. Voriconazole (Vor), an antifungal drug, can be loaded onto GO which retains the drug and promotes its sustained release from the hydrogel-based contact lenses. The contact lenses also exhibited good antimicrobial functions in view of glycidyltrimethylammonium chloride and silver nanoparticles. The results from in vitro and in vivo experiments demonstrate that contact lenses loaded with Vor have excellent efficacy in antifungal activity in vitro and could significantly enhance the therapeutic effects on a fungus-infected mouse model. The results indicate that this hydrogel contact lenses-based drug delivery system might be a promising therapeutic approach for a rapid and effective treatment of fungal keratitis.

  14. Energy level alignment and electron transport through metal/organic contacts. From interfaces to molecular electronics

    Energy Technology Data Exchange (ETDEWEB)

    Abad, Enrique

    2013-07-01

    A new calculational approach to describing metal/organic interfaces. A valuable step towards a better understanding of molecular electronics. Nominated as an outstanding contribution by the Autonomous University of Madrid. In recent years, ever more electronic devices have started to exploit the advantages of organic semiconductors. The work reported in this thesis focuses on analyzing theoretically the energy level alignment of different metal/organic interfaces, necessary to tailor devices with good performance. Traditional methods based on density functional theory (DFT), are not appropriate for analyzing them because they underestimate the organic energy gap and fail to correctly describe the van der Waals forces. Since the size of these systems prohibits the use of more accurate methods, corrections to those DFT drawbacks are desirable. In this work a combination of a standard DFT calculation with the inclusion of the charging energy (U) of the molecule, calculated from first principles, is presented. Regarding the dispersion forces, incorrect long range interaction is substituted by a van der Waals potential. With these corrections, the C60, benzene, pentacene, TTF and TCNQ/Au(111) interfaces are analyzed, both for single molecules and for a monolayer. The results validate the induced density of interface states model.

  15. Magnetic attachment for implant overdentures: influence of contact relationship with the denture base on stability and bending strain.

    Science.gov (United States)

    Yang, Tsung-Chieh; Maeda, Yoshinobu; Gonda, Tomoya; Wada, Masahiro

    2013-01-01

    This study evaluated how the contact height between the magnetic attachment and denture base influences stability and bending strain. An implant modified with strain gauges and a magnetic attachment mounted in an acrylic resin block were used to characterize systems with varying degrees or heights of contact with the abutment. Bending strain under lateral loading increased significantly as the contact height decreased. In the no contact and resilient contact groups, magnetic assemblies separated at reduced bending strain in all loading conditions. The contact height of the magnetic attachment influenced the stability and the amount of bending strain on the implant.

  16. Contact lens compliance among a group of young, university-based lens users in South India.

    Science.gov (United States)

    Noushad, Babu; Saoji, Yeshwant; Bhakat, Premjit; Thomas, Jyothi

    2012-01-01

    To investigate the rate of compliance with the soft contact lens care and maintenance procedures with a focus on contact lens wearing habits, cleaning and disinfecting procedures, and maintenance of lens care accessories in a group of young, university-based contact lens wearers Two hundred and sixteen young soft contact lens wearers with an age range of 18-22 years were selected conveniently from the student population of Manipal University, Manipal, India. After receiving informed consent from the participants, their level of compliance with contact lenses was assessed using a questionnaire. The mean (±SD) age of the participants was 21.86±2.35 years. Out of 216 subjects, only 34% of the lens users were identified to be compliant with the least level of compliance observed in the maintenance of lens care accessories. Conventional users showed significantly (p=0.001) better level of compliance compared to disposable wearers and so did the users who acquired their lenses from clinicians (p=0.001) compared to over-the-counter lens receipt. The gender (p=0.496) and years of experience in contact lens use (p=0.142) did not show any statistically significant difference in the level of compliance. This study demonstrated that non-compliance with lens care procedures among a group of young, university-based soft contact lens wearers is common. The results indicated that all subjects had some degree of non-compliance and the least level of compliance observed in the care of lens accessories.

  17. Energy performance of windows based on the net energy gain

    DEFF Research Database (Denmark)

    Svendsen, Svend; Kragh, Jesper; Laustsen, Jacob Birck

    2005-01-01

    The paper presents a new method to set up energy performance requirements and energy classes for windows of all dimensions and configurations. The net energy gain of windows is the solar gain minus the heat loss integrated over the heating season. The net energy gain can be calculated for one...... orientation or averaged over different orientations. The averaged value may be used for energy labeling of windows of standard size. Requirements in building codes may also be based on the net energy gain instead of the thermal transmittance of the window. The size and the configuration of the window, i.......e. number of glazing units, have a very large effect on the net energy gain. Therefore the energy labeling or the requirements based on the standard size may not give valid information on the energy performance of windows of non-standard size. The paper presents a method to set up requirements and classes...

  18. On the physically based modeling of surface tension and moving contact lines with dynamic contact angles on the continuum scale

    NARCIS (Netherlands)

    Huber, M.; Keller, F.; Säckel, W.; Hirschler, M.; Kunz, P.; Hassanizadeh, S.M.; Nieken, U.

    2016-01-01

    The description of wetting phenomena is a challenging problem on every considerable length-scale. The behavior of interfaces and contact lines on the continuum scale is caused by intermolecular interactions like the Van der Waals forces. Therefore, to describe surface tension and the resulting

  19. Analysis of PdGe-based contact on n-GaSb

    Science.gov (United States)

    Ghita, R. V.; Negrila, C. C.; Predoi, D.; Trusca, R.

    2018-02-01

    Pd-Ge based ohmic contacts on III-V semiconductor e.g. Pd-Ge on n-GaAs are viewed as a viable alternative to low contact resistance metallization. As it was remarked [1], together with the device dimensions decrease, the AuGeNi metallization system becomes inadequate for shallow-junction devices. This characteristic is related to the formation of a low melting point β-AuGa phase that leads to a poor contact thermal stability. Gallium Antimonide is anIII-V semiconductor compound that can be used in a photovoltaic convertor of GaAs/GaSb tandem stack with a predicted efficiency of 30%. Reduced series resistance on GaSb cells can be achieved by the improving of contact metallization properties. The present study is dedicated to the preparation conditions and structural analyzing of PdGe based contacts on n-GaSb, namely: Pd/Au/Ge. There are presented the depth profiling for PdGe metallization obtained from XPS measurements, and morphologic studies arisen from SEM technique and AFM technique.

  20. Measuring energy efficiency: Is energy intensity a good evidence base?

    International Nuclear Information System (INIS)

    Proskuryakova, L.; Kovalev, A.

    2015-01-01

    Highlights: • Energy intensity measure reflects consumption, not energy efficiency. • Thermodynamic indicators should describe energy efficiency at all levels. • These indicators should have no reference to economic or financial parameters. • A set of energy efficiency indicators should satisfy several basic principles. • There are trade-offs between energy efficiency, power and costs. - Abstract: There is a widespread assumption in energy statistics and econometrics that energy intensity and energy efficiency are equivalent measures of energy performance of economies. The paper points to the discrepancy between the engineering concept of energy efficiency and the energy intensity as it is understood in macroeconomic statistics. This double discrepancy concerns definitions (while engineering concept of energy efficiency is based on the thermodynamic definition, energy intensity includes economic measures) and use. With regard to the latter, the authors conclude that energy intensity can only provide indirect and delayed evidence of technological and engineering energy efficiency of energy conversion processes, which entails shortcomings for management and policymaking. Therefore, we suggest to stop considering subsectoral, sectoral and other levels of energy intensities as aggregates of lower-level energy efficiency. It is suggested that the insufficiency of energy intensity indicators can be compensated with the introduction of thermodynamic indicators describing energy efficiency at the physical, technological, enterprise, sub-sector, sectoral and national levels without references to any economic or financial parameters. Structured statistical data on thermodynamic efficiency is offered as a better option for identifying break-through technologies and technological bottle-necks that constrain efficiency advancements. It is also suggested that macro-level thermodynamic indicators should be based on the thermodynamic first law efficiency and the energy

  1. For a rational energy transition based on nuclear energy

    International Nuclear Information System (INIS)

    Chalmin, Philippe

    2014-06-01

    After having recalled the meaning of the concept of energy transition, and stated that this concept is a fuzzy one, this paper addresses the issue of the future of energy through the concept of Energy returned on Energy invested (EROI). It discusses this approach by outlining that energy is the initial driver of economy, and by showing that only hydroelectricity, coal, nuclear and wind energy have a sufficient return rate, and that shale gas is an energy source for the short and medium term. Then, based on data related to world energy resources and consumption, to electric power production from various sources, to pollution health impacts, to electricity prices for industries and for households, it discusses the sustainability of the energy mix regarding energy reserves, health issues, and economic issues. Some examples (Spain, Germany) illustrate economic problems faced by some renewable energies. Finally, the authors outline that, thanks to its nuclear policy, France is the western country which is the most committed in energy transition. Some proposals are made to support nuclear energy, to reduce the use of fossil energies, to launch an ambitious research policy (on energy storage, on photovoltaic energy, on CO 2 hydrogenation, on hydrogen as a fuel), in favour of energy mixes decided at national levels in Europe

  2. Numerical method for the adhesive normal contact analysis based on a Dugdale approximation

    NARCIS (Netherlands)

    Bazr Afshan Fadafan, M.; De Rooij, M.B.; Valefi, M.; Schipper, D.J.

    2017-01-01

    Modeling adhesion between two contacting surfaces plays a vital role in nano-tribology. However, providing analytical models, although desirable, is mostly impossible, in particular for complex geometries. Therefore, much attention has to be paid to numerical modeling of this phenomenon. Based on

  3. [Airborne contact allergy provoked by kathon in water-based plastic paint].

    Science.gov (United States)

    Kristensen, Diana; Hein, Hans Ole; Weismann, Kaare

    2002-04-29

    We describe two cases of airborne contact allergy to plastic paint containing Kathon. Two women with known kathon allergy, aged 33 and 50 years, developed severe dermatitis and systemic reactions after painting their homes with water-based plastic paint with Kathon as preservative. Both required treatment with systemic steroids. On return to their homes, the symptoms immediately recurred, and they were forced to stay away for several weeks afterwards. Patients allergic to Kathon should be informed of the risk of airborne contact allergy when exposed to paints preserved with Kathon.

  4. Advanced Fibre Based Energy Storage

    Science.gov (United States)

    Reid, Daniel Oliver

    New energy storage devices are required to enable future technologies. With the rise of wearable consumer and medical devices, a suitable flexible and wearable means of storing electrical energy is required. Fibre-based devices present a possible method of achieving this aim. Fibres are inherently more flexible than their bulk counterparts, and as such can be employed to form the electrodes of flexible batteries and capacitors. They also present a facile possibility for incorporation into many fabrics and clothes, further boosting their potential for use in wearable devices. Electrically conducting fibres were produced from a dispersion of carbon nanomaterials in a room temperature ionic liquid. Coagulation of this dispersion was achieved through manual injection into aqueous solutions of xanthan gum. The limitations of this method are highlighted by very low ultimate tensile strengths of these fibres, in the order of 3 MPa, with high variation within all of the fibres. Fibres were also produced via scrolling of bi-component films containing poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and poly(vinyl alcohol) (PVA). Chemical treatments were employed to impart water compatibility to these fibres, and their electrochemical, physical and electrical properties were analysed. Fibres were wet spun from two PEDOT:PSS sources, in several fibre diameters. The effect of chemical treatments on the fibres were investigated and compared. Short 5 min treatment times with dimethyl sulfoxide (DMSO) on 20 mum fibres produced from Clevios PH1000 were found to produce the best overall treatment. Up to a six-fold increase in electrical conductivity resulted, reaching 800 S cm-1, with up to 40 % increase in specific capacitance and no loss of mechanical strength (55 F g-1 and 150 MPa recorded). A wet spinning system to produce PEDOT:PSS fibres containing functionalised graphenes and carbon nanotubes, as well as birnessite nanotubes was subsequently developed

  5. Optimization of contact conditions between iron base alloys and mercury at room temperature

    International Nuclear Information System (INIS)

    Medina-Almazan, L.; Rouchaud, J.-C.; Auger, T.; Gorse, D.

    2008-01-01

    The intimate contact or wetting of iron-base alloys by mercury is obtained at room temperature by varying the environmental conditions, quasi immediately for Armco iron and a high purity Fe-25Ni alloy, after ∼30 min of contact for the 316L/Hg couple, after one week of contact for the T91/Hg couple. Careful mechanical polishing allows for wetting the notches of CCT specimens made in T91 steel with Hg, whereas chemical etching in 4%HCl is required to wet 316L SS identical specimens. Using ICP-OES measurements, values of solubility limit are given for both Fe (45.5 ± 0.4 wt ppm) and Cr (0.56 ± 0.07 wt ppm) in mercury at room temperature, the one of nickel (2.6 ± 0.39 wt ppm) being in agreement with the literature data

  6. Optimization of contact conditions between iron base alloys and mercury at room temperature

    Science.gov (United States)

    Medina-Almazán, L.; Rouchaud, J.-C.; Auger, T.; Gorse, D.

    2008-03-01

    The intimate contact or wetting of iron-base alloys by mercury is obtained at room temperature by varying the environmental conditions, quasi immediately for Armco iron and a high purity Fe-25Ni alloy, after ˜30 min of contact for the 316L/Hg couple, after one week of contact for the T91/Hg couple. Careful mechanical polishing allows for wetting the notches of CCT specimens made in T91 steel with Hg, whereas chemical etching in 4%HCl is required to wet 316L SS identical specimens. Using ICP-OES measurements, values of solubility limit are given for both Fe (45.5 ± 0.4 wt ppm) and Cr (0.56 ± 0.07 wt ppm) in mercury at room temperature, the one of nickel (2.6 ± 0.39 wt ppm) being in agreement with the literature data.

  7. Effects of weak and strong localization in tunnel characteristics of contacts on HTSC base

    International Nuclear Information System (INIS)

    Revenko, Yu.V.; Svistunov, V.M.; Grigut', O.V.; Belogolovskij, M.A.; Khachaturov, A.I.

    1992-01-01

    It is found that a phenomena governed by the electronic processes in the disordered surface normal layer of material are observed in the tunnel contatcs bases on metal oxide superconductors of 1-2-3 group. Measured characteristics σ(U)=dI/dU ore determined both by contact's barrier properties and conductivity in the disordered region of metal oxides in the vicinity of a barrier. As regards high-temperature contacts σ(U) value at high temperatures us determined by the Schottky barrier and at low temperatures - by activation processes of charge transfer over strongly localized states in near-the-barrier region of the contact. Crossing over towards logarithmic dependence in the tunnel conductuvity σ(U) of low-Ohmic transitions are attributed to the occurrence of 2D state density conditions in the tunnel surface layers of metal oxides

  8. Friendly-Sharing: Improving the Performance of City Sensoring through Contact-Based Messaging Applications

    Directory of Open Access Journals (Sweden)

    Jorge Herrera-Tapia

    2016-09-01

    Full Text Available Regular citizens equipped with smart devices are being increasingly used as “sensors” by Smart Cities applications. Using contacts among users, data in the form of messages is obtained and shared. Contact-based messaging applications are based on establishing a short-range communication directly between mobile devices, and on storing the messages in these devices for subsequent delivery to cloud-based services. An effective way to increase the number of messages that can be shared is to increase the contact duration. We thus introduce the Friendly-Sharing diffusion approach, where, during a contact, the users are aware of the time needed to interchange the messages stored in their buffers, and they can thus decide to wait more time in order to increase the message sharing probability. The performance of this approach is anyway closely related to the size of the buffer in the device. We therefore compare various policies either for the message selection at forwarding times and for message dropping when the buffer is full. We evaluate our proposal with a modified version of the Opportunistic Networking Environment (ONE simulator and using real human mobility traces.

  9. Friendly-Sharing: Improving the Performance of City Sensoring through Contact-Based Messaging Applications.

    Science.gov (United States)

    Herrera-Tapia, Jorge; Hernández-Orallo, Enrique; Tomás, Andrés; Manzoni, Pietro; Tavares Calafate, Carlos; Cano, Juan-Carlos

    2016-09-18

    Regular citizens equipped with smart devices are being increasingly used as "sensors" by Smart Cities applications. Using contacts among users, data in the form of messages is obtained and shared. Contact-based messaging applications are based on establishing a short-range communication directly between mobile devices, and on storing the messages in these devices for subsequent delivery to cloud-based services. An effective way to increase the number of messages that can be shared is to increase the contact duration. We thus introduce the Friendly-Sharing diffusion approach, where, during a contact, the users are aware of the time needed to interchange the messages stored in their buffers, and they can thus decide to wait more time in order to increase the message sharing probability. The performance of this approach is anyway closely related to the size of the buffer in the device. We therefore compare various policies either for the message selection at forwarding times and for message dropping when the buffer is full. We evaluate our proposal with a modified version of the Opportunistic Networking Environment (ONE) simulator and using real human mobility traces.

  10. Diagnosis of three types of constant faults in read-once contact networks over finite bases

    KAUST Repository

    Busbait, Monther I.

    2016-03-24

    We study the depth of decision trees for diagnosis of three types of constant faults in read-once contact networks over finite bases containing only indecomposable networks. For each basis and each type of faults, we obtain a linear upper bound on the minimum depth of decision trees depending on the number of edges in networks. For bases containing networks with at most 10 edges, we find sharp coefficients for linear bounds.

  11. Diagnosis of constant faults in read-once contact networks over finite bases

    KAUST Repository

    Busbait, Monther I.

    2015-03-01

    We study the depth of decision trees for diagnosis of constant 0 and 1 faults in read-once contact networks over finite bases containing only indecomposable networks. For each basis, we obtain a linear upper bound on the minimum depth of decision trees depending on the number of edges in the networks. For bases containing networks with at most 10 edges we find coefficients for linear bounds which are close to sharp. © 2014 Elsevier B.V. All rights reserved.

  12. Non-contact pumping of light emitters via non-radiative energy transfer

    Science.gov (United States)

    Klimov, Victor I.; Achermann, Marc

    2010-01-05

    A light emitting device is disclosed including a primary light source having a defined emission photon energy output, and, a light emitting material situated near to said primary light source, said light emitting material having an absorption onset equal to or less in photon energy than the emission photon energy output of the primary light source whereby non-radiative energy transfer from said primary light source to said light emitting material can occur yielding light emission from said light emitting material.

  13. Causal Analysis of the Inadvertent Contact with an Uncontrolled Electrical Hazardous Energy Source (120 Volts AC)

    Energy Technology Data Exchange (ETDEWEB)

    David E. James; Dennis E. Raunig; Sean S. Cunningham

    2014-10-01

    On September 25, 2013, a Health Physics Technician (HPT) was performing preparations to support a pneumatic transfer from the HFEF Decon Cell to the Room 130 Glovebox in HFEF, per HFEF OI 3165 section 3.5, Field Preparations. This activity involves an HPT setting up and climbing a portable ladder to remove the 14-C meter probe from above ball valve HBV-7. The HPT source checks the meter and probe and then replaces the probe above HBV-7, which is located above Hood ID# 130 HP. At approximately 13:20, while reaching past the HBV-7 valve position indicator switches in an attempt to place the 14-C meter probe in the desired location, the HPT’s left forearm came in contact with one of the three sets of exposed terminals on the valve position indication switches for HBV 7. This resulted in the HPT receiving an electrical shock from a 120 Volt AC source. Upon moving the arm, following the electrical shock, the HPT noticed two exposed electrical connections on a switch. The HPT then notified the HFEF HPT Supervisor, who in turn notified the MFC Radiological Controls Manager and HFEF Operations Manager of the situation. Work was stopped in the area and the hazard was roped off and posted to prevent access to the hazard. The HPT was escorted by the HPT Supervisor to the MFC Dispensary and then preceded to CFA medical for further evaluation. The individual was evaluated and released without any medical restrictions. Causal Factor (Root Cause) A3B3C01/A5B2C08: - Knowledge based error/Attention was given to wrong issues - Written Communication content LTA, Incomplete/situation not covered The Causal Factor (root cause) was attention being given to the wrong issues during the creation, reviews, verifications, and actual performance of HFEF OI-3165, which covers the need to perform the weekly source check and ensure placement of the probe prior to performing a “rabbit” transfer. This resulted in the hazard not being identified and mitigated in the procedure. Work activities

  14. Design, fabrication and skin-electrode contact analysis of polymer microneedle-based ECG electrodes

    Science.gov (United States)

    O'Mahony, Conor; Grygoryev, Konstantin; Ciarlone, Antonio; Giannoni, Giuseppe; Kenthao, Anan; Galvin, Paul

    2016-08-01

    Microneedle-based ‘dry’ electrodes have immense potential for use in diagnostic procedures such as electrocardiography (ECG) analysis, as they eliminate several of the drawbacks associated with the conventional ‘wet’ electrodes currently used for physiological signal recording. To be commercially successful in such a competitive market, it is essential that dry electrodes are manufacturable in high volumes and at low cost. In addition, the topographical nature of these emerging devices means that electrode performance is likely to be highly dependent on the quality of the skin-electrode contact. This paper presents a low-cost, wafer-level micromoulding technology for the fabrication of polymeric ECG electrodes that use microneedle structures to make a direct electrical contact to the body. The double-sided moulding process can be used to eliminate post-process via creation and wafer dicing steps. In addition, measurement techniques have been developed to characterize the skin-electrode contact force. We perform the first analysis of signal-to-noise ratio dependency on contact force, and show that although microneedle-based electrodes can outperform conventional gel electrodes, the quality of ECG recordings is significantly dependent on temporal and mechanical aspects of the skin-electrode interface.

  15. Design, fabrication and skin-electrode contact analysis of polymer microneedle-based ECG electrodes

    International Nuclear Information System (INIS)

    O’Mahony, Conor; Grygoryev, Konstantin; Ciarlone, Antonio; Giannoni, Giuseppe; Kenthao, Anan; Galvin, Paul

    2016-01-01

    Microneedle-based ‘dry’ electrodes have immense potential for use in diagnostic procedures such as electrocardiography (ECG) analysis, as they eliminate several of the drawbacks associated with the conventional ‘wet’ electrodes currently used for physiological signal recording. To be commercially successful in such a competitive market, it is essential that dry electrodes are manufacturable in high volumes and at low cost. In addition, the topographical nature of these emerging devices means that electrode performance is likely to be highly dependent on the quality of the skin-electrode contact.This paper presents a low-cost, wafer-level micromoulding technology for the fabrication of polymeric ECG electrodes that use microneedle structures to make a direct electrical contact to the body. The double-sided moulding process can be used to eliminate post-process via creation and wafer dicing steps. In addition, measurement techniques have been developed to characterize the skin-electrode contact force. We perform the first analysis of signal-to-noise ratio dependency on contact force, and show that although microneedle-based electrodes can outperform conventional gel electrodes, the quality of ECG recordings is significantly dependent on temporal and mechanical aspects of the skin-electrode interface. (paper)

  16. Research on Stiffness Measurement of Spring Tubes Based on Three-Dimensional Conformal Contacts Model

    International Nuclear Information System (INIS)

    Li, Y F; Wang, G L; Lu, Z S; Shao, D X

    2006-01-01

    A contact model and corresponding numerical method are proposed in this paper to study the influences of contact deformations on stiffness measuring precision of spring tubes. Firstly, measuring principle and the force analysis are presented. Then, the contact model is set up by simplifying the contact force and considering the real contact condition. Lastly, a numerical method is developed to solve the contact equation, and quantizing relationships between measurement errors and the contact deformation are derived subsequently. It's proved by simulation and tests that the contact model is more accurate than Herzian contact theory and the contact deformation can make stiffness values lower than its true ones

  17. Faults and energy losses in electric contacts; Fallas y perdidas de energia en contactos electricos

    Energy Technology Data Exchange (ETDEWEB)

    Bratu Serban, Neagu; Campero Littlewood, Eduardo [Universidad Autonoma Metropolitana, Mexico, D. F. (Mexico)

    1993-12-31

    In this paper a brief description is made of the behavior of the electric contacts and the elements that affect in the heat release during its operation. The mathematical expressions describing this phenomenon are presented. The losses that can be produced at the contacts are evaluated and the graphs, where the behavior of these different operating conditions can be seen, are included. [Espanol] En este articulo se hace una breve descripcion del comportamiento de los contactos electricos y de los elementos que influyen en la generacion de calor durante su operacion. Se presentan las expresiones con las que se describe matematicamente este fenomeno. Se evaluan las perdidas que pueden llegar a tenerse en los contactos y se incluyen graficas donde puede verse el comportamiento de estos en diferentes condiciones de operacion.

  18. Layered Double Hydroxide Nanoplatelets with Excellent Tribological Properties under High Contact Pressure as Water-Based Lubricant Additives

    Science.gov (United States)

    Wang, Hongdong; Liu, Yuhong; Chen, Zhe; Wu, Bibo; Xu, Sailong; Luo, Jianbin

    2016-01-01

    High efficient and sustainable utilization of water-based lubricant is essential for saving energy. In this paper, a kind of layered double hydroxide (LDH) nanoplatelets is synthesized and well dispersed in water due to the surface modification with oleylamine. The excellent tribological properties of the oleylamine-modified Ni-Al LDH (NiAl-LDH/OAm) nanoplatelets as water-based lubricant additives are evaluated by the tribological tests in an aqueous environment. The modified LDH nanoplatelets are found to not only reduce the friction but also enhance the wear resistance, compared with the water-based cutting fluid and lubricants containing other particle additives. By adding 0.5 wt% LDH nanoplatelets, under 1.5 GPa initial contact pressure, the friction coefficient, scar diameter, depth and width of the wear track dramatically decrease by 83.1%, 43.2%, 88.5% and 59.5%, respectively. It is considered that the sufficiently small size and the excellent dispersion of NiAl-LDH/OAm nanoplatelets in water are the key factors, so as to make them enter the contact area, form a lubricating film and prevent direct collision of asperity peaks. Our investigations demonstrate that the LDH nanoplatelet as a water-based lubricant additive has a great potential value in industrial application. PMID:26951794

  19. Acceptable risk of contact allergy in the general population assessed by CE-DUR--a method to detect and categorize contact allergy epidemics based on patient data

    DEFF Research Database (Denmark)

    Thyssen, Jacob Pontoppidan; Menné, Torkil; Schnuch, Axel

    2009-01-01

    population by using a new epidemiological tool. The clinical epidemiology (CE) and drug utilization research (DUR) method recently estimated the 10-year contact allergy prevalence in the general population in Germany and Denmark based on patch test reading data in combination with an estimate of the number...

  20. Optical properties of photodetectors based on single GaN nanowires with a transparent graphene contact

    Energy Technology Data Exchange (ETDEWEB)

    Babichev, A. V., E-mail: A.Babichev@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Institute (Russian Federation); Zhang, H.; Guan, N. [University Paris Saclay, Institut d’Electronique Fondamentale, UMR 8622 CNRS (France); Egorov, A. Yu. [ITMO University (Russian Federation); Julien, F. H.; Messanvi, A. [University Paris Saclay, Institut d’Electronique Fondamentale, UMR 8622 CNRS (France); Durand, C.; Eymery, J. [University Grenoble Alpes (France); Tchernycheva, M. [University Paris Saclay, Institut d’Electronique Fondamentale, UMR 8622 CNRS (France)

    2016-08-15

    We report the fabrication and optical and electrical characterization of photodetectors for the UV spectral range based on single p–n junction nanowires with a transparent contact of a new type. The contact is based on CVD-grown (chemical-vapor deposition) graphene. The active region of the nitride nanowires contains a set of 30 radial In{sub 0.18}Ga{sub 0.82}N/GaN quantum wells. The structure is grown by metal-organic vaporphase epitaxy. The photodetectors are fabricated using electron-beam lithography. The current–voltage characteristics exhibit a rectifying behavior. The spectral sensitivity of the photodetector is recorded starting from 3 eV and extending far in the UV range. The maximal photoresponse is observed at a wavelength of 367 nm (sensitivity 1.9 mA/W). The response switching time of the photodetector is less than 0.1 s.

  1. Simulation Research on Micro Contact Based on Force in Silicon Wafer Rotation Grinding

    Science.gov (United States)

    Ren, Qinglei; Wei, Xin; Xie, Xiaozhu; Hu, Wei

    2017-10-01

    Silicon wafer rotation grinding with cup type diamond wheel is a typical ultra precision grinding process. In this paper, a simulation model based on force for micro contact between wheel micro unit and silicon wafer is established from the stable ductile grinding process. Micro contact process in grinding is simulated using the nonlinear explicit finite element analysis software LS-DYNA. The stress-strain results on silicon wafer and wheel micro unit are analyzed by finite element method. The results show that the critical displacement and load corresponding elastic to plastic - plastic to brittle exist on silicon wafer. In silicon plastic zone tangential sliding can produce plastic groove and uplift. Wear of wheel micro unit can be based on the simulation data to judge. The research provides support for wafer grinding and wheel wear mechanism.

  2. ZnO nanowire photodetectors based on Schottky contact with surface passivation

    Science.gov (United States)

    Zhang, Dakuan; Sheng, Yun; Wang, Jianyu; Gao, Fan; Yan, Shancheng; Wang, Junzhuan; Pan, Lijia; Wan, Qing; Shi, Yi

    2017-07-01

    Performance characteristics, such as dark current and response time, of ZnO nanowire (NW) photodetectors are usually degraded by H2O/O2 adsorption on the NW surfaces. In this work, ZnO NW photodetectors based on Au Schottky contact through passivating surface states were investigated. ZnO NW photodetectors were fabricated with a lateral electrode structure, in which Au served as Au/ZnO Schottky contact and semi-transparent top electrode. Specifically, passivation of the surface states of ZnO NWs by using highly intensive UV irradiation effectively improved the photoresponse. A physical model based on surface band theory was developed to understand the origin of the performance improvement of the photodetector. The present device architecture prevents ZnO NWs photodetector from H2O/O2 adsorption in air and efficiently extracts photogenerated carriers across a diametrical direction.

  3. Encouraging adolescents to contact their GP: a community-based trial.

    Science.gov (United States)

    Aarseth, Svein; Dalen, Ingvild; Haavet, Ole Rikard

    2014-05-01

    Adolescents, especially males, often fail to see their GP. To determine whether an informative letter could enhance the accessibility and utilisation of healthcare facilities and services. A community-based trial in one town in Oslo, using a retrospective control group. GPs in one town in Oslo sent a personal, informative letter at the beginning of 2008 and 2009 to individuals in their practice population who were turning 16 years of age that year. The pooled data for the same year for each surgery were collected. Retrospective data from 1990 and 1991 served as controls for the intervention groups of data collected in 2006 and 2007 respectively. An International Classification of Primary Care-2 diagnosis was given for each contact. The proportion of adolescents in contact with a GP increased from 59% in the control group to 69% in the intervention group (P<0.001). For the males, the increase was from 54% to 72% (P<0.001). This reduced sex differences in healthcare seeking. For diagnoses mentioned in the informative letter the incidence rose from 38% in the control group to 55% in the intervention group (P<0.001). For the females, there was a non-significant increase in the proportion in contact with the GP, from 63% to 66% in control and intervention groups, respectively. The most frequent contact reasons were respiratory disorders, followed by general and unspecified complaints, skin disorders, musculoskeletal disorders, and psychological disorders. This pattern did not change because of the intervention. An information letter about health problems and health rights (such as the protection of the adolescent's privacy) seems to enhance the accessibility and utilisation of GPs, as measured by contact rate, particularly for males.

  4. A low energy muon spin rotation and point contact tunneling study of niobium films prepared for superconducting cavities

    Science.gov (United States)

    Junginger, Tobias; Calatroni, S.; Sublet, A.; Terenziani, G.; Prokscha, T.; Salman, Z.; Suter, A.; Proslier, T.; Zasadzinski, J.

    2017-12-01

    Point contact tunneling and low energy muon spin rotation are used to probe, on the same samples, the surface superconducting properties of micrometer thick niobium films deposited onto copper substrates using different sputtering techniques: diode, dc magnetron and HIPIMS. The combined results are compared to radio-frequency tests performances of RF cavities made with the same processes. Degraded surface superconducting properties are found to correlate to lower quality factors and stronger Q-slope. In addition, both techniques find evidence for surface paramagnetism on all samples and particularly on Nb films prepared by HIPIMS.

  5. Non-contact evaluation of milk-based products using air-coupled ultrasound

    Science.gov (United States)

    Meyer, S.; Hindle, S. A.; Sandoz, J.-P.; Gan, T. H.; Hutchins, D. A.

    2006-07-01

    An air-coupled ultrasonic technique has been developed and used to detect physicochemical changes of liquid beverages within a glass container. This made use of two wide-bandwidth capacitive transducers, combined with pulse-compression techniques. The use of a glass container to house samples enabled visual inspection, helping to verify the results of some of the ultrasonic measurements. The non-contact pulse-compression system was used to evaluate agglomeration processes in milk-based products. It is shown that the amplitude of the signal varied with time after the samples had been treated with lactic acid, thus promoting sample destabilization. Non-contact imaging was also performed to follow destabilization of samples by scanning in various directions across the container. The obtained ultrasonic images were also compared to those from a digital camera. Coagulation with glucono-delta-lactone of skim milk poured into this container could be monitored within a precision of a pH of 0.15. This rapid, non-contact and non-destructive technique has shown itself to be a feasible method for investigating the quality of milk-based beverages, and possibly other food products.

  6. Non-Contact Plant Growth Measurement Method and System Based on Ubiquitous Sensor Network Technologies

    Directory of Open Access Journals (Sweden)

    Intae Ryoo

    2011-04-01

    Full Text Available This paper proposes a non-contact plant growth measurement system using infrared sensors based on the ubiquitous sensor network (USN technology. The proposed system measures plant growth parameters such as the stem radius of plants using real-time non-contact methods, and generates diameter, cross-sectional area and thickening form of plant stems using this measured data. Non-contact sensors have been used not to cause any damage to plants during measurement of the growth parameters. Once the growth parameters are measured, they are transmitted to a remote server using the sensor network technology and analyzed in the application program server. The analyzed data are then provided for administrators and a group of interested users. The proposed plant growth measurement system has been designed and implemented using fixed-type and rotary-type infrared sensor based measurement methods and devices. Finally, the system performance is compared and verified with the measurement data that have been obtained by practical field experiments.

  7. 2D halide perovskite-based van der Waals heterostructures: contact evaluation and performance modulation

    Science.gov (United States)

    Guo, Yaguang; Saidi, Wissam A.; Wang, Qian

    2017-09-01

    Halide perovskites and van der Waals (vdW) heterostructures are both of current interest owing to their novel properties and potential applications in nano-devices. Here, we show the great potential of 2D halide perovskite sheets (C4H9NH3)2PbX4 (X  =  Cl, Br and I) that were synthesized recently (Dou et al 2015 Science 349 1518-21) as the channel materials contacting with graphene and other 2D metallic sheets to form van der Waals heterostructures for field effect transistor (FET). Based on state-of-the-art theoretical simulations, we show that the intrinsic properties of the 2D halide perovskites are preserved in the heterojunction, which is different from the conventional contact with metal surfaces. The 2D halide perovskites form a p-type Schottky barrier (Φh) contact with graphene, where tunneling barrier exists, and a negative band bending occurs at the lateral interface. We demonstrate that the Schottky barrier can be turned from p-type to n-type by doping graphene with nitrogen atoms, and a low-Φh or an Ohmic contact can be realized by doping graphene with boron atoms or replacing graphene with other high-work-function 2D metallic sheets such as ZT-MoS2, ZT-MoSe2 and H-NbS2. This study not only predicts a 2D halide perovskite-based FETs, but also enhances the understanding of tuning Schottky barrier height in device applications.

  8. Energy information data base: subject thesaurus

    International Nuclear Information System (INIS)

    1979-10-01

    The technical staff of the DOE Technical Information Center, during its subject indexing activities, develops and structures a vocabulary that allows consistent machine storage and retrieval of information necessary to the accomplishment of the DOE mission. This thesaurus incorporates that structured vocabulary. The terminology of this thesaurus is used for the subject control of information announced in DOE Energy Research Abstracts, Energy Abstracts for Policy Analysis, Solar Energy Update, Geothermal Energy Update, Fossil Energy Update, Fusion Energy Update, and Energy Conservation Update. This terminology also facilitates subject searching of the DOE energy information data base, a research in progress data base, a general and practical energy information data base, power reactor docket information data base, nuclear science abstracts data base, and the federal energy information data base on the DOE on-line retrieval system, RECON. The rapid expansion of the DOE's activities will result in a concomitant thesaurus expansion as information relating to new activities is indexed. Only the terms used in the indexing of documents at the Technical Information Center to date are included

  9. Ultracoatings: Enabling Energy and Power Solutions in High Contact Stress Environments through next-generation Nanocoatings Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Clifton B. Higdon III

    2012-03-20

    . Advancing this technology, called Ultracoatings, through initial development, scale up, and commercialization to a variety of markets would represent a transformative leap to surface engineering. Several application spaces were considered for immediate implementation of the Ultracoatings technology, including, but not limited to, a drive shaft for an aerospace fuel pump, engine timing components, and dry solids pump hardware for an innovative coal gasifier. The primary focus of the program was to evaluate and screen the performance of the selected (Ti, Zr)B2 Ultracoatings composition for future development. This process included synthesis of the material for physical vapor deposition, sputtering trials and coating characterization, friction and wear testing on sample coupons, and functional hardware testing. The main project deliverables used to gage the project's adherence to its original objective were: Development of a coating/substrate pairing that exhibits wear rate of 0.1 mg/hour or lower at a 1GPa contact pressure, while achieving a maximum coating cost of $0.10/cm2. Demonstrate the aforementioned wear rate in both lubricated and starved lubrication conditions. Although the (Ti, Zr) B2 coating was not tailored for low friction performance, friction and wear evaluations of the material demonstrated a coefficient of sliding friction as low as 0.09. This suggests that varying the percentage of TiB2 present in the composite could enhance the materials performance in water-based lubricants. In the aerospace drive shaft application, functional hardware coated with (Ti, Zr)B2 survived a variety of abuse and long-range durability tests, with contact pressures exceeding 2 GPa. For engine timing components, further work is planned to evaluate the Ultracoatings technology in direct injection and diesel engine conditions. In the final identified application space the dry solids pump hardware, discussions continue on the application of the Ultracoatings technology for those

  10. APPLICATION OF DIRECT CONTACT TEST IN EVALUATION OF CYTOTOXICITY OF ACRYLIC DENTURE BASE RESINS

    Directory of Open Access Journals (Sweden)

    Milena Kostić

    2012-03-01

    Full Text Available The use of acrylic denture base resins is widely spread in dental practice. They belong to the group of biomaterials due to their role of morphological and functional substituent in the mouth. However, clinical practice has shown that some toxic ingredients of these materials may lead to adverse local and even systemic changes. The aim of the study was to evaluate cytotoxic effect of various denture base resins on cell culture using direct contact test. The effect of four different acrylic materials on HeLa cell structure was evaluated. Upon light microscopy analysis, MTT test was performed without previous removal of material samples. The obtained values of MTT indicate that cell proliferation is dependant on the type of acrylic denture base resins. Cold polymerization denture base resins showed mild inhibitory effect on the cell culture growth. The signs of toxicity were not observed in heat polymerization denture base resins.

  11. Energy Flexometer: Transactive Energy-Based Internet of Things Technology

    Directory of Open Access Journals (Sweden)

    Muhammad Babar

    2018-03-01

    Full Text Available Effective Energy Management with an active Demand Response (DR is crucial for future smart energy system. Increasing number of Distributed Energy Resources (DER, local microgrids and prosumers have an essential and real influence on present power distribution system and generate new challenges in power, energy and demand management. A relatively new paradigm in this field is transactive energy (TE, with its value and market-based economic and technical mechanisms to control energy flows. Due to a distributed structure of present and future power system, the Internet of Things (IoT environment is needed to fully explore flexibility potential from the end-users and prosumers, to offer a bid to involved actors of the smart energy system. In this paper, new approach to connect the market-driven (bottom-up DR program with current demand-driven (top-down energy management system (EMS is presented. Authors consider multi-agent system (MAS to realize the approach and introduce a concept and standardize the design of new Energy Flexometer. It is proposed as a fundamental agent in the method. Three different functional blocks have been designed and presented as an IoT platform logical interface according to the LonWorks technology. An evaluation study has been performed as well. Results presented in the paper prove the proposed concept and design.

  12. Pinch analysis for efficient energy utilization in IGCC plants: Incorporation of contact economiser

    CSIR Research Space (South Africa)

    Madzivhandila, VA

    2010-09-01

    Full Text Available Pinch analysis was used in this work to exploit the amount of energy available within integrated gasification combined cycle (IGCC) power plants. This work focuses on the steam path (subsystem) of IGCC power plants only. A case study on the Elcogas...

  13. Contact light-emitting diodes based on vertical ZnO nanorods

    International Nuclear Information System (INIS)

    Panin, G. N.; Cho, H. D.; Lee, S. W.; Kang, T. W.

    2014-01-01

    We report vertical contact light-emitting diodes (VCLEDs), that are based on heterojunctions formed by using the point contacts of n-ZnO nanorods (NRs) to the p-type semiconductor substrate and that are fabricated using a new approach to the formation of LEDs (Appl. Phys. Lett. 98, 093110 (2011)). A p-type GaN film grown on a sapphire substrate was used to form n-ZnO NRs/pGaN VCLEDs on a large area of about 4 cm 2 . The VCLEDs emitted a pure blue electroluminescence with high efficiency. Electroluminescence at 470 nm, which is visible to the naked eye, started at small current of about 50 μA and is attributed to the good optical properties of the structurally perfect heterojunctions in the point contacts. The VCLED configuration allows the creation of ZnO/p-GaN nano-LEDs of high density and high-quality with a greatly reduced concentration of nonradiative defects in the active regions. The VCLEDs showed the high brightness of light required for active matrix displays and general solid-state lighting.

  14. Neonatal non-contact respiratory monitoring based on real-time infrared thermography

    Directory of Open Access Journals (Sweden)

    Abbas Abbas K

    2011-10-01

    Full Text Available Abstract Background Monitoring of vital parameters is an important topic in neonatal daily care. Progress in computational intelligence and medical sensors has facilitated the development of smart bedside monitors that can integrate multiple parameters into a single monitoring system. This paper describes non-contact monitoring of neonatal vital signals based on infrared thermography as a new biomedical engineering application. One signal of clinical interest is the spontaneous respiration rate of the neonate. It will be shown that the respiration rate of neonates can be monitored based on analysis of the anterior naris (nostrils temperature profile associated with the inspiration and expiration phases successively. Objective The aim of this study is to develop and investigate a new non-contact respiration monitoring modality for neonatal intensive care unit (NICU using infrared thermography imaging. This development includes subsequent image processing (region of interest (ROI detection and optimization. Moreover, it includes further optimization of this non-contact respiration monitoring to be considered as physiological measurement inside NICU wards. Results Continuous wavelet transformation based on Debauches wavelet function was applied to detect the breathing signal within an image stream. Respiration was successfully monitored based on a 0.3°C to 0.5°C temperature difference between the inspiration and expiration phases. Conclusions Although this method has been applied to adults before, this is the first time it was used in a newborn infant population inside the neonatal intensive care unit (NICU. The promising results suggest to include this technology into advanced NICU monitors.

  15. Neonatal non-contact respiratory monitoring based on real-time infrared thermography

    Science.gov (United States)

    2011-01-01

    Background Monitoring of vital parameters is an important topic in neonatal daily care. Progress in computational intelligence and medical sensors has facilitated the development of smart bedside monitors that can integrate multiple parameters into a single monitoring system. This paper describes non-contact monitoring of neonatal vital signals based on infrared thermography as a new biomedical engineering application. One signal of clinical interest is the spontaneous respiration rate of the neonate. It will be shown that the respiration rate of neonates can be monitored based on analysis of the anterior naris (nostrils) temperature profile associated with the inspiration and expiration phases successively. Objective The aim of this study is to develop and investigate a new non-contact respiration monitoring modality for neonatal intensive care unit (NICU) using infrared thermography imaging. This development includes subsequent image processing (region of interest (ROI) detection) and optimization. Moreover, it includes further optimization of this non-contact respiration monitoring to be considered as physiological measurement inside NICU wards. Results Continuous wavelet transformation based on Debauches wavelet function was applied to detect the breathing signal within an image stream. Respiration was successfully monitored based on a 0.3°C to 0.5°C temperature difference between the inspiration and expiration phases. Conclusions Although this method has been applied to adults before, this is the first time it was used in a newborn infant population inside the neonatal intensive care unit (NICU). The promising results suggest to include this technology into advanced NICU monitors. PMID:22243660

  16. Contact-Free Detection of Obstructive Sleep Apnea Based on Wavelet Information Entropy Spectrum Using Bio-Radar

    Directory of Open Access Journals (Sweden)

    Fugui Qi

    2016-08-01

    Full Text Available Judgment and early danger warning of obstructive sleep apnea (OSA is meaningful to the diagnosis of sleep illness. This paper proposed a novel method based on wavelet information entropy spectrum to make an apnea judgment of the OSA respiratory signal detected by bio-radar in wavelet domain. It makes full use of the features of strong irregularity and disorder of respiratory signal resulting from the brain stimulation by real, low airflow during apnea. The experimental results demonstrated that the proposed method is effective for detecting the occurrence of sleep apnea and is also able to detect some apnea cases that the energy spectrum method cannot. Ultimately, the comprehensive judgment accuracy resulting from 10 groups of OSA data is 93.1%, which is promising for the non-contact aided-diagnosis of the OSA.

  17. Polyaniline nanoparticle-based solid-contact silicone rubber ion-selective electrodes for ultratrace measurements.

    Science.gov (United States)

    Lindfors, Tom; Szücs, Júlia; Sundfors, Fredrik; Gyurcsányi, Róbert E

    2010-11-15

    Silicone rubber (SR)-based solid-contact ion-selective electrodes (ISEs) have been prepared for the first time with an electrically conducting polymer as the solid-contact (SC) layer. The Ca(2+)- and Ag(+)-selective electrodes were based on the ionophores ETH 1001 and o-xylylenebis(N,N-diisobutyl dithiocarbamate), respectively, integrated in room temperature vulcanizing silicone rubber (RTV 3140). The SC consisted of a polyaniline nanoparticle dispersion, which was found to considerably lower the impedance of the SCISEs in comparison to the SR-based coated wire electrodes (CWE). For the CaSCISEs, the bulk membrane resistance decreased from 700 MΩ (CaCWE) to 35 MΩ. Both the Ca(2+)- and Ag(+)-selective SCISEs exhibited nanomolar detection limits with fast Nernstian responses down to 10(-8) M. The potential response of the SCISEs was not influenced by light. The selectivities of the CaSCISEs were similar and for the AgSCISE better than their plasticized PVC-based analogues. Thus, SR seems to be a viable alternative to PVC membranes in ISE applications that require low water uptake, good adhesion, and robust and fast potential responses at submicromolar sample concentrations.

  18. Patterns of Contact with Hospital for Children with an Autism Spectrum Disorder: A Danish Register-Based Study

    Science.gov (United States)

    Atladottir, Hjordis Osk; Schendel, Diana E.; Lauritsen, Marlene B.; Henriksen, Tine Brink; Parner, Erik T.

    2012-01-01

    The aim of this study was to study patterns of contact with hospital for children with autism spectrum disorder (ASD) using Danish population based register data. We included all children born in Denmark from 1994 through 2002. We found that children diagnosed with ASD had an increased rate of contact with hospital, almost regardless of the cause…

  19. CONSRANK: a server for the analysis, comparison and ranking of docking models based on inter-residue contacts

    KAUST Repository

    Chermak, Edrisse

    2014-12-21

    Summary: Herein, we present CONSRANK, a web tool for analyzing, comparing and ranking protein–protein and protein–nucleic acid docking models, based on the conservation of inter-residue contacts and its visualization in 2D and 3D interactive contact maps.

  20. An elastography method based on the scanning contact resonance of a piezoelectric cantilever

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Ji; Li, Faxin, E-mail: lifaxin@pku.edu.cn [State Key Lab for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871, China and HEDPS, Center for Applied Physics and Technologies, Peking University, Beijing 100871 (China)

    2013-12-15

    Purpose: Most tissues may become significantly stiffer than their normal states when there are lesions inside. The tissue's modulus can then act as an identification parameter for clinic diagnosis of tumors or fibrosis, which leads to elastography. This study introduces a novel elastography method that can be used for modulus imaging of superficial organs. Methods: This method is based on the scanning contact-resonance of a unimorph piezoelectric cantilever. The cantilever vibrates in its bending mode with the tip pressed tightly on the sample. The contact resonance frequency of the cantilever-sample system is tracked at each scanning point, from which the sample's modulus can be derived based on a beam dynamic model and a contact mechanics model. Scanning is performed by a three-dimensional motorized stage and the whole system is controlled by a homemade software program based on LabVIEW. Results: Testing onin vitro beef tissues indicates that the fat and the muscle can be easily distinguished using this system, and the accuracy of the modulus measurement can be comparable with that of nanoindentation. Imaging on homemade gelatin phantoms shows that the depth information of the abnormalities can be qualitatively obtained by varying the pressing force. The detection limit of this elastography method is specially examined both experimentally and numerically. Results show that it can detect the typical lesions in superficial organs with the depth of several centimeters. The lateral resolution of this elastography method/system is better than 0.5 mm, and could be further enhanced by using more scanning points. Conclusions: The proposed elastography system can be regarded as a sensitive palpation robot, which may be very promising in early diagnosis of tumors in superficial organs such as breast and thyroid.

  1. Agent based energy management systems

    Energy Technology Data Exchange (ETDEWEB)

    Wolter, Martin

    2012-07-01

    In liberalized, regulated energy markets, the different participants - namely producers and consumers of energy, transmission and distribution system operators as well as regulatory authorities - have partly divergent and partly convergent interests. Loads, power plants and grid operators try to maximize their own benefit in this highly complex environment accepting to act detrimentally to others. Although the relationship between the participants is mostly competitive, there are some fundamental shared interests, e.g. voltage stability, a constant system frequency or efficient energy production, transmission and distribution, which are endangered e.g. by increased injection of volatile sources in low and medium voltage grids, displacement of stabilizing bulk generation and the slowly progressing extension of the electric grid. There is a global consensus, that the resulting challenges can efficiently be faced using information and communication technologies to coordinate grid utilization and operation. The basic idea is to benefit from unused reserves by participating in deployment of system services e.g. reactive power supply to keep the voltage within certain bounds. The coordination can best be done by the grid operator. All activities of that kind are summarized under the umbrella term ''Smart Grid''. To simultaneously model the behavior and interests of different types of market participants and their convergent and divergent interests, multi-agent systems are used. They offer a perfectly fitting framework for this sort of game theory and can easily be adapted to all kinds of new challenges of electricity markets. In this work, multi-agent systems are used to either cooperatively or competitively solve problems in distribution and transmission systems. Therefore, conventional algorithms have to be modified to converge into multiple local optima using only small pieces of the entire system information. It is clearly stated, that personal

  2. Contact-less magneto-elastic torsional sensor based on phase-shift measurements

    International Nuclear Information System (INIS)

    Buchenau, D; Schmidt, G; Eckert, S

    2014-01-01

    We report on the development of a contact-less measurement technique for torsional shear stress τ in ferromagnetic axles or hollow shafts, based on the magneto-elastic effect. In general, two different measuring principles for ferromagnetic materials can be realized, based on: the evaluation of the change of magnetic polarization influenced by shear stress ΔJ(τ) or the change of the magnetic susceptibility Δχ A (τ). The comprehension of the magnetic polarization or the magnetic susceptibility in a sensor concept requires an external magnetic field. Alternating magnetic fields were used as shear stress can disturb not only the amplitude but also the phase distribution of the applied magnetic field. As a result of a torsional moment acting on an axle or hollow shaft, an angle of twist η appears, which is constant over the length of the twisted object. This angle of twist can be understood as a shift of infinitesimal thin cross-sections in which the whole length of the axle is separated. Besides the macroscopic deformation effect, shear forces also affect the Weiss-domains in the micro-scale of the ferromagnetic material. The effects in the micro-scale are the base of the magneto-elastic effect. The combination of the deformation effect in the macro-scale and the deformation of the Weiss-domains in the micro-scale leads to a sophisticated measurement principle for torsional stress in axles or hollow shafts. Magneto-sensitive detectors along or around the measurement object open up the possibility for a contact-less detection of torsional stress in ferromagnetic materials. Besides a strong measuring signal, free from electromagnetic interference, the introduced contact-less measurement principle offers different advantages, like independence from compression strength, nominal tensile stress, impact load, ferromagnetic hysteresis effects and independence of the temperature-dependent electrical conductivity of the axle or hollow shaft. The characteristics of such

  3. Nanolithography based contacting method for electrical measurements on single template synthesized nanowires

    DEFF Research Database (Denmark)

    Fusil, S.; Piraux, L.; Mátéfi-Tempfli, Stefan

    2005-01-01

    A reliable method enabling electrical measurements on single nanowires prepared by electrodeposition in an alumina template is described. This technique is based on electrically controlled nanoindentation of a thin insulating resist deposited on the top face of the template filled by the nanowires....... We show that this method is very flexible, allowing us to electrically address single nanowires of controlled length down to 100 nm and of desired composition. Using this approach, current densities as large as 10 A cm were successfully injected through a point contact on a single magnetic...

  4. Non-contact metrology of aspheric surfaces based on MWLI technology

    Science.gov (United States)

    Berger, G.; Petter, J.

    2013-09-01

    A non-contact optical scanning metrology solution measuring aspheric surfaces is presented, which is based on multi wavelength interferometry (MWLI). The technology yields high density 3D data in short measurement times (including set up time) and provides high, reproducible form measurement accuracy. It measures any asphere without restrictions in terms of spherical departures. In addition, measurement of a large variety of special optics is enabled, such as annular lenses, segmented optics, optics with diffractive steps, ground optics, optics made of opaque and transparent materials, and small and thin optics (e.g. smart phone lenses). The measurement instrument can be used under production conditions.

  5. Non-contact angle measurement based on parallel multiplex laser feedback interferometry

    International Nuclear Information System (INIS)

    Zhang Song; Tan Yi-Dong; Zhang Shu-Lian

    2014-01-01

    We present a novel precise angle measurement scheme based on parallel multiplex laser feedback interferometry (PLFI), which outputs two parallel laser beams and thus their displacement difference reflects the angle variation of the target. Due to its ultrahigh sensitivity to the feedback light, PLFI realizes the direct non-contact measurement of non-cooperative targets. Experimental results show that PLFI has an accuracy of 8″ within a range of 1400″. The yaw of a guide is also measured and the experimental results agree with those of the dual-frequency laser interferometer Agilent 5529A. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  6. Energy budgets’ formation based on incomplete data

    Directory of Open Access Journals (Sweden)

    Litvak Valery

    2017-01-01

    Full Text Available The universal technique of the current energy budget calculation is recommended for several periods of time. Basing on the data of annual energy budget and considering the plant’s features, social, climatic and other conditions, correcting factors are calculated to estimate energy resources consumption for the day, week, month and year. Shortterm current energy budget supports important financial, trade, logistic, organizational and other control directions. The developed technique is applicable for subnational entities and industrial enterprises in order to increase level of energy resources consumption planning and forecasting as well as bills’ optimization.

  7. Contact State Estimation by Vision-based Tactile Sensors for Dexterous Manipulation with Robot Hands Based on Shape-Sensing

    Directory of Open Access Journals (Sweden)

    Yuji Ito

    2011-09-01

    Full Text Available We propose a new method for estimating the contact state of objects with varying shapes on a vision‐ based fluid‐type tactile sensor, which touch pad is an elastic transparent membrane of silicon rubber with dotted pattern printed on its inner side. The membrane is filled with translucent red colored water. The proposed method leads to better understanding of the object

  8. Contact State Estimation by Vision-Based Tactile Sensors for Dexterous Manipulation with Robot Hands Based on Shape-Sensing

    Directory of Open Access Journals (Sweden)

    Yuji Ito

    2011-09-01

    Full Text Available We propose a new method for estimating the contact state of objects with varying shapes on a vision-based fluid-type tactile sensor, which touch pad is an elastic transparent membrane of silicon rubber with dotted pattern printed on its inner side. The membrane is filled with translucent red colored water. The proposed method leads to better understanding of the object's shape and movement, and can be applied for accomplishing reliable and dexterous handling tasks by robot hands.

  9. Energy flow modeling and optimal operation analysis of the micro energy grid based on energy hub

    International Nuclear Information System (INIS)

    Ma, Tengfei; Wu, Junyong; Hao, Liangliang

    2017-01-01

    Highlights: • Design a novel architecture for energy hub integrating power hub, cooling hub and heating hub. • The micro energy grid based on energy hub is introduced and its advantages are discussed. • Propose a generic modeling method for the energy flow of micro energy grid. • Propose an optimal operation model for micro energy grid with considering demand response. • The roles of renewable energy, energy storage devices and demand response are discussed separately. - Abstract: The energy security and environmental problems impel people to explore a more efficient, environment friendly and economical energy utilization pattern. In this paper, the coordinated operation and optimal dispatch strategies for multiple energy system are studied at the whole Micro Energy Grid level. To augment the operation flexibility of energy hub, the innovation sub-energy hub structure including power hub, heating hub and cooling hub is put forward. Basing on it, a generic energy hub architecture integrating renewable energy, combined cooling heating and power, and energy storage devices is developed. Moreover, a generic modeling method for the energy flow of micro energy grid is proposed. To minimize the daily operation cost, a day-ahead dynamic optimal operation model is formulated as a mixed integer linear programming optimization problem with considering the demand response. Case studies are undertaken on a community Micro Energy Grid in four different scenarios on a typical summer day and the roles of renewable energy, energy storage devices and demand response are discussed separately. Numerical simulation results indicate that the proposed energy flow modeling and optimal operation method are universal and effective over the entire energy dispatching horizon.

  10. Surface morphology effects in a vibration based triboelectric energy harvester

    Science.gov (United States)

    Nafari, A.; Sodano, H. A.

    2018-01-01

    Despite the abundance of ambient mechanical energy in our environment, it is often neglected and left unused. However, recent studies have demonstrated that mechanical vibrations can be harvested and used to power small wireless electronic devices, such as micro electromechanical sensors (MEMS) and actuators. Most commonly, these energy harvesters convert vibration into electrical energy by utilizing piezoelectric, electromagnetic or electrostatic effects. Recently, triboelectric based energy harvesters have shown to be among the simplest and most cost-effective techniques for scavenging mechanical energy. The basis of triboelectric energy harvesters is the periodic contact and separation of two surfaces with opposite triboelectric properties which results in induced charge flow through an external load. Here, a vibration driven triboelectric nanogenerator (TENG) is fabricated and the effect of micro/nano scale surface modification is studied. The TENG produces electrical energy on the basis of periodic out-of-plane charge separation between gold and polydimethylsiloxane (PDMS) with opposite triboelectric charge polarities. By introducing micro/nano scale surface modifications to the PDMS and gold, the TENG’s power output is further enhanced. This work demonstrates that the morphology of the surfaces in a TENG device is important and by increasing the effective surface area through micro/nano scale modification, the power output of the device can increase by 118%. Moreover, it is shown that unlike many TENGs proposed in the literature, the fabricated device has a high RMS open circuit voltage and short circuit current and can perform for an extended period of time.

  11. Conclusions. [hydrogen-based energy

    Science.gov (United States)

    1975-01-01

    Conclusions are presented according to general areas of technology with some specific examples of research and technology needs identified. These conclusions provide a base for the future development of detailed program plans and identify research needs that are not being given attention or are not being supported at a sufficient level. Emphasis is placed on hydrogen production and use.

  12. Toward Annealing-Stable Molybdenum-Oxide-Based Hole-Selective Contacts For Silicon Photovoltaics

    KAUST Repository

    Essig, Stephanie

    2018-02-21

    Molybdenum oxide (MoOX) combines a high work function with broadband optical transparency. Sandwiched between a hydrogenated intrinsic amorphous silicon passivation layer and a transparent conductive oxide, this material allows a highly efficient hole-selective front contact stack for crystalline silicon solar cells. However, hole extraction from the Si wafer and transport through this stack degrades upon annealing at 190 °C, which is needed to cure the screen-printed Ag metallization applied to typical Si solar cells. Here, we show that effusion of hydrogen from the adjacent layers is a likely cause for this degradation, highlighting the need for hydrogen-lean passivation layers when using such metal-oxide-based carrier-selective contacts. Pre-MoOX-deposition annealing of the passivating a-Si:H layer is shown to be a straightforward approach to manufacturing MoOX-based devices with high fill factors using screen-printed metallization cured at 190 °C.

  13. Adaptive local surface refinement based on LR NURBS and its application to contact

    Science.gov (United States)

    Zimmermann, Christopher; Sauer, Roger A.

    2017-12-01

    A novel adaptive local surface refinement technique based on Locally Refined Non-Uniform Rational B-Splines (LR NURBS) is presented. LR NURBS can model complex geometries exactly and are the rational extension of LR B-splines. The local representation of the parameter space overcomes the drawback of non-existent local refinement in standard NURBS-based isogeometric analysis. For a convenient embedding into general finite element codes, the Bézier extraction operator for LR NURBS is formulated. An automatic remeshing technique is presented that allows adaptive local refinement and coarsening of LR NURBS. In this work, LR NURBS are applied to contact computations of 3D solids and membranes. For solids, LR NURBS-enriched finite elements are used to discretize the contact surfaces with LR NURBS finite elements, while the rest of the body is discretized by linear Lagrange finite elements. For membranes, the entire surface is discretized by LR NURBS. Various numerical examples are shown, and they demonstrate the benefit of using LR NURBS: Compared to uniform refinement, LR NURBS can achieve high accuracy at lower computational cost.

  14. A reduction-based exact algorithm for the contact map overlap problem.

    Science.gov (United States)

    Xie, Wei; Sahinidis, Nikolaos V

    2007-06-01

    Aligning proteins based on their structural similarity is a fundamental problem in molecular biology with applications in many settings, including structure classification, database search, function prediction, and assessment of folding prediction methods. Structural alignment can be done via several methods, including contact map overlap (CMO) maximization that aligns proteins in a way that maximizes the number of common residue contacts. In this paper, we develop a reduction-based exact algorithm for the CMO problem. Our approach solves CMO directly rather than after transformation to other combinatorial optimization problems. We exploit the mathematical structure of the problem in order to develop a number of efficient lower bounding, upper bounding, and reduction schemes. Computational experiments demonstrate that our algorithm runs significantly faster than existing exact algorithms and solves some hard CMO instances that were not solved in the past. In addition, the algorithm produces protein clusters that are in excellent agreement with the SCOP classification. An implementation of our algorithm is accessible as an on-line server at http://eudoxus.scs.uiuc.edu/cmos/cmos.html.

  15. The Contact State Monitoring for Seal End Faces Based on Acoustic Emission Detection

    Directory of Open Access Journals (Sweden)

    Xiaohui Li

    2016-01-01

    Full Text Available Monitoring the contact state of seal end faces would help the early warning of the seal failure. In the acoustic emission (AE detection for mechanical seal, the main difficulty is to reduce the background noise and to classify the dispersed features. To solve these problems and achieve higher detection rates, a new approach based on genetic particle filter with autoregression (AR-GPF and hypersphere support vector machine (HSSVM is presented. First, AR model is used to build the dynamic state space (DSS of the AE signal, and GPF is used for signal filtering. Then, multiple features are extracted, and a classification model based on HSSVM is constructed for state recognition. In this approach, AR-GPF is an excellent time-domain method for noise reduction, and HSSVM has advantage on those dispersed features. Finally experimental data shows that the proposed method can effectively detect the contact state of the seal end faces and has higher accuracy rates than some other existing methods.

  16. Temperature-Dependent Charge Transport through Individually Contacted DNA Origami-Based Au Nanowires.

    Science.gov (United States)

    Teschome, Bezu; Facsko, Stefan; Schönherr, Tommy; Kerbusch, Jochen; Keller, Adrian; Erbe, Artur

    2016-10-11

    DNA origami nanostructures have been used extensively as scaffolds for numerous applications such as for organizing both organic and inorganic nanomaterials, studying single molecule reactions, and fabricating photonic devices. Yet, little has been done toward the integration of DNA origami nanostructures into nanoelectronic devices. Among other challenges, the technical difficulties in producing well-defined electrical contacts between macroscopic electrodes and individual DNA origami-based nanodevices represent a serious bottleneck that hinders the thorough characterization of such devices. Therefore, in this work, we have developed a method to electrically contact individual DNA origami-based metallic nanowires using electron beam lithography. We then characterize the charge transport of such nanowires in the temperature range from room temperature down to 4.2 K. The room temperature charge transport measurements exhibit ohmic behavior, whereas at lower temperatures, multiple charge transport mechanisms such as tunneling and thermally assisted transport start to dominate. Our results confirm that charge transport along metallized DNA origami nanostructures may deviate from pure metallic behavior due to several factors including partial metallization, seed inhomogeneities, impurities, and weak electronic coupling among AuNPs. Besides, this study further elucidates the importance of variable temperature measurements for determining the dominant charge transport mechanisms for conductive nanostructures made by self-assembly approaches.

  17. Energy based prediction models for building acoustics

    DEFF Research Database (Denmark)

    Brunskog, Jonas

    2012-01-01

    In order to reach robust and simplified yet accurate prediction models, energy based principle are commonly used in many fields of acoustics, especially in building acoustics. This includes simple energy flow models, the framework of statistical energy analysis (SEA) as well as more elaborated...... principles as, e.g., wave intensity analysis (WIA). The European standards for building acoustic predictions, the EN 12354 series, are based on energy flow and SEA principles. In the present paper, different energy based prediction models are discussed and critically reviewed. Special attention is placed...... on underlying basic assumptions, such as diffuse fields, high modal overlap, resonant field being dominant, etc., and the consequences of these in terms of limitations in the theory and in the practical use of the models....

  18. Modeling and characterization of double resonant tunneling diodes for application as energy selective contacts in hot carrier solar cells

    Science.gov (United States)

    Jehl, Zacharie; Suchet, Daniel; Julian, Anatole; Bernard, Cyril; Miyashita, Naoya; Gibelli, Francois; Okada, Yoshitaka; Guillemolles, Jean-Francois

    2017-02-01

    Double resonant tunneling barriers are considered for an application as energy selective contacts in hot carrier solar cells. Experimental symmetric and asymmetric double resonant tunneling barriers are realized by molecular beam epitaxy and characterized by temperature dependent current-voltage measurements. The negative differential resistance signal is enhanced for asymmetric heterostructures, and remains unchanged between low- and room-temperatures. Within Tsu-Esaki description of the tunnel current, this observation can be explained by the voltage dependence of the tunnel transmission amplitude, which presents a resonance under finite bias for asymmetric structures. This effect is notably discussed with respect to series resistance. Different parameters related to the electronic transmission of the structure and the influence of these parameters on the current voltage characteristic are investigated, bringing insights on critical processes to optimize in double resonant tunneling barriers applied to hot carrier solar cells.

  19. Base Program on Energy Related Research

    Energy Technology Data Exchange (ETDEWEB)

    Western Research Institute

    2008-06-30

    The main objective of the Base Research Program was to conduct both fundamental and applied research that will assist industry in developing, deploying, and commercializing efficient, nonpolluting fossil energy technologies that can compete effectively in meeting the energy requirements of the Nation. In that regard, tasks proposed under the WRI research areas were aligned with DOE objectives of secure and reliable energy; clean power generation; development of hydrogen resources; energy efficiency and development of innovative fuels from low and no-cost sources. The goal of the Base Research Program was to develop innovative technology solutions that will: (1) Increase the production of United States energy resources--coal, natural gas, oil, and renewable energy resources; (2) Enhance the competitiveness of United States energy technologies in international markets and assist in technology transfer; (3) Reduce the nation's dependence on foreign energy supplies and strengthen both the United States and regional economies; and (4) Minimize environmental impacts of energy production and utilization. This report summarizes the accomplishments of the overall Base Program. This document represents a stand-alone Final Report for the entire Program. It should be noted that an interim report describing the Program achievements was prepared in 2003 covering the progress made under various tasks completed during the first five years of this Program.

  20. Smart-phone based computational microscopy using multi-frame contact imaging on a fiber-optic array

    OpenAIRE

    Navruz, Isa; Coskun, Ahmet F.; Wong, Justin; Mohammad, Saqib; Tseng, Derek; Nagi, Richie; Phillips, Stephen; Ozcan, Aydogan

    2013-01-01

    We demonstrate a cellphone based contact microscopy platform, termed Contact Scope, which can image highly dense or connected samples in transmission mode. Weighing approximately 76 grams, this portable and compact microscope is installed on the existing camera unit of a cellphone using an opto-mechanical add-on, where planar samples of interest are placed in contact with the top facet of a tapered fiber-optic array. This glass-based tapered fiber array has ∼9 fold higher density of fiber opt...

  1. Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, A., E-mail: alexander.schmid@physik.tu-freiberg.de; Schroeter, Ch.; Otto, R.; Heitmann, J. [Institute of Applied Physics, TU Bergakademie Freiberg, 09599 Freiberg (Germany); Schuster, M. [Namlab gGmbH, 01187 Dresden (Germany); Klemm, V.; Rafaja, D. [Institute of Materials Science, TU Bergakademie Freiberg, 09599 Freiberg (Germany)

    2015-02-02

    Ohmic contacts with V/Al/Ni/Au and V/Ni/Au metalization schemes were deposited on AlGaN/GaN heterostructures. The dependence of the specific contact resistance on the annealing conditions and the V:Al thickness ratio was shown. For an optimized electrode stack, a low specific contact resistance of 8.9 × 10{sup −6} Ω cm{sup 2} was achieved at an annealing temperature of 650 °C. Compared to the conventional Ti/Al/Ni/Au contact, this is a reduction of 150 K. The microstructure and contact formation at the AlGaN/metal interface were investigated by transmission electron microscopy including high-resolution micrographs and energy dispersive X-ray analysis. It was shown that for low-resistive contacts, the resistivity of the metalization has to be taken into account. The V:Al thickness ratio has an impact on the formation of different intermetallic phases and thus is crucial for establishing ohmic contacts at reduced annealing temperatures.

  2. Observer-Based Perturbation Extremum Seeking Control with Input Constraints for Direct-Contact Membrane Distillation Process

    KAUST Repository

    Eleiwi, Fadi

    2017-05-08

    An Observer-based Perturbation Extremum Seeking Control (PESC) is proposed for a Direct-Contact Membrane Distillation (DCMD) process. The process is described with a dynamic model that is based on a 2D Advection-Diffusion Equation (ADE) model which has pump flow rates as process inputs. The objective of the controller is to optimize the trade-off between the permeate mass flux and the energy consumption by the pumps inside the process. Cases of single and multiple control inputs are considered through the use of only the feed pump flow rate or both the feed and the permeate pump flow rates. A nonlinear Lyapunov-based observer is designed to provide an estimation for the temperature distribution all over the designated domain of the DCMD process. Moreover, control inputs are constrained with an anti-windup technique to be within feasible and physical ranges. Performance of the proposed structure is analyzed, and simulations based on real DCMD process parameters for each control input are provided.

  3. Effects of contact-based mental illness stigma reduction programs: age, gender, and Asian, Latino, and White American differences.

    Science.gov (United States)

    Wong, Eunice C; Collins, Rebecca L; Cerully, Jennifer L; Yu, Jennifer W; Seelam, Rachana

    2018-03-01

    Mental illness stigma disproportionately affects help seeking among youth, men, and ethnic minorities. As part of a comprehensive statewide initiative to reduce mental illness stigma and discrimination in California, a broad set of contact-based educational programs were widely disseminated. This study examined whether the effects of contact-based educational programs varied depending on the age, gender, and race-ethnicity of participants. Participants (N = 4122) attended a contact-based educational program that was delivered as part of the statewide initiative to reduce mental illness stigma and discrimination. Self-administered surveys assessing beliefs, attitudes, and intentions toward mental illnesses and treatment were conducted immediately before and after participation in contact-based educational programs. Participant age, gender, and race-ethnicity significantly moderated pre-post changes in mental illness stigma. Although all groups exhibited significant pre-post changes across most of the stigma domains assessed, young adults, females, and Asian and Latino American participants reported larger improvements compared to older adults, males, and Whites, respectively. Findings suggest that contact-based educational programs can achieve immediate reductions in mental illness stigma across a variety of sociodemographic groups and may particularly benefit young adults and racial-ethnic minorities. Further research is needed to assess whether contact-based educational programs can sustain longer-term changes and aid in the reduction of disparities in mental illness stigma and treatment.

  4. Influence of solepieces on the displacements of horizontally loaded support bases of a contact system

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2014-09-01

    Full Text Available The bearings of a contact system on transport, electric lines take up substantial horizontal loads both from wires and constructions holding them and also from wind, dynamic and other extraordinary influences (wire breakage, emergency situations, etc.. In case of using contact bearers with sole bases it is necessary to have sufficient strength and strain capacity reserve. For this aim solepieces with different constructive schemes are applied. The effectiveness of their application depending on their location, depth and length has not been thoroughly researched. In the article the authors offer a calculation method for horizontally loaded bearings with solepieces presented as horizontally laid beams, which are used in order to raise the deformational stability of horizontally loaded bearings. The results of comparative calculations are presented for horizontally loaded sole bearings with beams, installed in the upper and lower compressed zones of soil. The calculation results showed the efficiency of solepieces application with the aim of deformation reduction of horizontally loaded bearings as well as the possibility to optimally assign their size in order to reduce costs for their production.

  5. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

    1998-12-31

    Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

  6. Energy Information Data Base: serial titles

    International Nuclear Information System (INIS)

    1980-06-01

    The Department of Energy Technical Information Center (TIC) is responsible for creating bibliographic data bases that are used in the announcement and retrieval of publications dealing with all phases of energy. The TIC interactive information processing system makes use of a number of computerized authorities so that consistency can be maintained and indexes can be produced. One such authority is the Energy Information Data Base: Serial Titles. This authority contains the full and abbreviated journal title, country of publication, CODEN, and certain codes. This revision replaces previous revisions of this document

  7. A household-based study of contact networks relevant for the spread of infectious diseases in the highlands of Peru.

    Directory of Open Access Journals (Sweden)

    Carlos G Grijalva

    Full Text Available Few studies have quantified social mixing in remote rural areas of developing countries, where the burden of infectious diseases is usually the highest. Understanding social mixing patterns in those settings is crucial to inform the implementation of strategies for disease prevention and control. We characterized contact and social mixing patterns in rural communities of the Peruvian highlands.This cross-sectional study was nested in a large prospective household-based study of respiratory infections conducted in the province of San Marcos, Cajamarca-Peru. Members of study households were interviewed using a structured questionnaire of social contacts (conversation or physical interaction experienced during the last 24 hours. We identified 9015 reported contacts from 588 study household members. The median age of respondents was 17 years (interquartile range [IQR] 4-34 years. The median number of reported contacts was 12 (IQR 8-20 whereas the median number of physical (i.e. skin-to-skin contacts was 8.5 (IQR 5-14. Study participants had contacts mostly with people of similar age, and with their offspring or parents. The number of reported contacts was mainly determined by the participants' age, household size and occupation. School-aged children had more contacts than other age groups. Within-household reciprocity of contacts reporting declined with household size (range 70%-100%. Ninety percent of household contact networks were complete, and furthermore, household members' contacts with non-household members showed significant overlap (range 33%-86%, indicating a high degree of contact clustering. A two-level mixing epidemic model was simulated to compare within-household mixing based on observed contact networks and within-household random mixing. No differences in the size or duration of the simulated epidemics were revealed.This study of rural low-density communities in the highlands of Peru suggests contact patterns are highly assortative

  8. Endoluminal non-contact soft tissue ablation using fiber-based Er:YAG laser delivery

    Science.gov (United States)

    Kundrat, Dennis; Fuchs, Alexander; Schoob, Andreas; Kahrs, Lüder A.; Ortmaier, Tobias

    2016-03-01

    The introduction of Er:YAG lasers for soft and hard tissue ablation has proven promising results over the last decades due to strong absorption at 2.94 μm wavelength by water molecules. An extension to endoluminal applications demands laser delivery without mirror arms due to dimensional constraints. Therefore, fiber-based solutions are advanced to provide exible access while keeping space requirements to a minimum. Conventional fiber-based treatments aim at laser-tissue interactions in contact mode. However, this procedure is associated with disadvantages such as advancing decrease in power delivery due to particle coverage of the fiber tip, tissue carbonization, and obstructed observation of the ablation progress. The objective of this work is to overcome aforementioned limitations with a customized fiber-based module for non-contact robot-assisted endoluminal surgery and its associated experimental evaluation. Up to the authors knowledge, this approach has not been presented in the context of laser surgery at 2.94 μm wavelength. The preliminary system design is composed of a 3D Er:YAG laser processing unit enabling automatic laser to fiber coupling, a GeO2 solid core fiber, and a customized module combining collimation and focusing unit (focal length of 20 mm, outer diameter of 8 mm). The performance is evaluated with studies on tissue substitutes (agar-agar) as well as porcine samples that are analysed by optical coherence tomography measurements. Cuts (depths up to 3mm) with minimal carbonization have been achieved under adequate moistening and sample movement (1.5mms-1). Furthermore, an early cadaver study is presented. Future work aims at module miniaturization and integration into an endoluminal robot for scanning and focus adaptation.

  9. Color stabilities of calcium silicate-based materials in contact with different irrigation solutions.

    Science.gov (United States)

    Keskin, Cangul; Demiryurek, Ebru Ozsezer; Ozyurek, Taha

    2015-03-01

    Mineral trioxide aggregate (MTA) has been reported to cause tooth discoloration when applied in the esthetic zone. A previous study has shown discoloration of MTA in contact with root canal irrigation solutions. Moreover, there are limited data on color stability of novel calcium silicate-based materials. This study aimed to evaluate color changes of 4 calcium silicate-based materials in contact with different irrigation solutions. ProRoot white MTA (Dentsply Tulsa Dental, Johnson City, TN), white MTA Angelus (Angelus Solucoes Odontologicas, Londrina, Brazil), Biodentine (Septodont, Saint Maur des Fosses, France), and BioAggregate (Innovative Bioceramix, Vancouver, BC, Canada) samples were assessed. Materials were mixed according to the manufacturers' instructions. Cylindric samples (10-mm diameter and 2-mm height) were obtained by curing in molds for each material's setting time at 100% humidity and 37°C. Each specimen was immersed in 5% sodium hypochlorite, 2% chlorhexidine gluconate, or distilled water for 24 hours. Color changes were measured with a spectrophotometer. Data were analyzed by using 2-way analysis of variance and post hoc Bonferroni tests. All materials exhibited clinically perceptible discoloration when immersed in sodium hypochlorite and chlorhexidine gluconate. ProRoot white MTA showed a statistically significant difference from Bioaggregate, Biodentine, and white MTA Angelus. Distilled water did not cause clinically perceptible discoloration of any material. In esthetically critical regions, compounds free of bismuth oxide, Biodentine, and BioAggregate can be considered as alternatives to MTA. However, all calcium silicate-based materials exhibited clinically perceptible color changes. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. Who puts the most energy into energy conservation? A segmentation of energy consumers based on energy-related behavioral characteristics

    International Nuclear Information System (INIS)

    Sütterlin, Bernadette; Brunner, Thomas A.; Siegrist, Michael

    2011-01-01

    The present paper aims to identify and describe different types of energy consumers in a more comprehensive way than previous segmentation studies using cluster analysis. Energy consumers were segmented based on their energy-related behavioral characteristics. In addition to purchase- and curtailment-related energy-saving behavior, consumer classification was also based on acceptance of policy measures and energy-related psychosocial factors, so the used behavioral segmentation base was more comprehensive compared to other studies. Furthermore, differentiation between the energy-saving purchase of daily products, such as food, and of energy efficient appliances allowed a more differentiated characterization of the energy consumer segments. The cluster analysis revealed six energy consumer segments: the idealistic, the selfless inconsequent, the thrifty, the materialistic, the convenience-oriented indifferent, and the problem-aware well-being-oriented energy consumer. Findings emphasize that using a broader and more distinct behavioral base is crucial for an adequate and differentiated description of energy consumer types. The paper concludes by highlighting the most promising energy consumer segments and discussing possible segment-specific marketing and policy strategies. - Highlights: ► By applying a cluster-analytic approach, new energy consumer segments are identified. ► A comprehensive, differentiated description of the different energy consumer types is provided. ► A distinction between purchase of daily products and energy efficient appliances is essential. ► Behavioral variables are a more suitable base for segmentation than general characteristics.

  11. Current-voltage characteristics of quantum-point contacts in the closed-channel regime: Transforming the bias voltage into an energy scale

    DEFF Research Database (Denmark)

    Gloos, K.; Utko, P.; Aagesen, M.

    2006-01-01

    We investigate the I(V) characteristics (current versus bias voltage) of side-gated quantum-point contacts, defined in GaAs/AlxGa1-xAs heterostructures. These point contacts are operated in the closed-channel regime, that is, at fixed gate voltages below zero-bias pinch-off for conductance. Our....... Such a built-in energy-voltage calibration allows us to distinguish between the different contributions to the electron transport across the pinched-off contact due to thermal activation or quantum tunneling. The first involves the height of the barrier, and the latter also its length. In the model that we...

  12. Volumetric quantification of bone-implant contact using micro-computed tomography analysis based on region-based segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sung Won; Lee, Woo Jin; Choi, Soon Chul; Lee, Sam Sun; Heo, Min Suk; Huh, Kyung Hoe; Kim, Tae Il; Yi, Won Ji [Dental Research Institute, School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2015-03-15

    We have developed a new method of segmenting the areas of absorbable implants and bone using region-based segmentation of micro-computed tomography (micro-CT) images, which allowed us to quantify volumetric bone-implant contact (VBIC) and volumetric absorption (VA). The simple threshold technique generally used in micro-CT analysis cannot be used to segment the areas of absorbable implants and bone. Instead, a region-based segmentation method, a region-labeling method, and subsequent morphological operations were successively applied to micro-CT images. The three-dimensional VBIC and VA of the absorbable implant were then calculated over the entire volume of the implant. Two-dimensional (2D) bone-implant contact (BIC) and bone area (BA) were also measured based on the conventional histomorphometric method. VA and VBIC increased significantly with as the healing period increased (p<0.05). VBIC values were significantly correlated with VA values (p<0.05) and with 2D BIC values (p<0.05). It is possible to quantify VBIC and VA for absorbable implants using micro-CT analysis using a region-based segmentation method.

  13. Detection of needle to nerve contact based on electric bioimpedance and machine learning methods.

    Science.gov (United States)

    Kalvoy, Havard; Tronstad, Christian; Ullensvang, Kyrre; Steinfeldt, Thorsten; Sauter, Axel R

    2017-07-01

    In an ongoing project for electrical impedance-based needle guidance we have previously showed in an animal model that intraneural needle positions can be detected with bioimpedance measurement. To enhance the power of this method we in this study have investigated whether an early detection of the needle only touching the nerve also is feasible. Measurement of complex impedance during needle to nerve contact was compared with needle positions in surrounding tissues in a volunteer study on 32 subjects. Classification analysis using Support-Vector Machines demonstrated that discrimination is possible, but that the sensitivity and specificity for the nerve touch algorithm not is at the same level of performance as for intra-neuralintraneural detection.

  14. A Socially Aware Routing Based on Local Contact Information in Delay-Tolerant Networks

    Directory of Open Access Journals (Sweden)

    Chan-Myung Kim

    2014-01-01

    Full Text Available In delay-tolerant networks, network topology changes dynamically and there is no guarantee of continuous connectivity between any two nodes. These features make DTN routing one of important research issues, and the application of social network metrics has led to the design of recent DTN routing schemes. In this paper, we propose an efficient routing scheme by using a node’s local contact history and social network metrics. Each node first chooses a proper relay node based on the closeness to the destination node. A locally computed betweenness centrality is additionally utilized to enhance the routing efficiency. Through intensive simulation, we finally demonstrate that our algorithm performs efficiently compared to the existing epidemic or friendship routing scheme.

  15. Real time optimization of solar powered direct contact membrane distillation based on multivariable extremum seeking

    KAUST Repository

    Karam, Ayman M.

    2015-09-21

    This paper presents a real time optimization scheme for a solar powered direct contact membrane distillation (DCMD) water desalination system. The sun and weather conditions vary and are inconsistent throughout the day. Therefore, the solar powered DCMD feed inlet temperature is never constant, which influences the distilled water flux. The problem of DCMD process optimization has not been studied enough. In this work, the response of the process under various feed inlet temperatures is investigated, which demonstrates the need for an optimal controller. To address this issue, we propose a multivariable Newton-based extremum seeking controller which optimizes the inlet feed and permeate mass flow rates as the feed inlet temperature varies. Results are presented and discussed for a realistic temperature profile.

  16. MEMS based pyroelectric thermal energy harvester

    Science.gov (United States)

    Hunter, Scott R; Datskos, Panagiotis G

    2013-08-27

    A pyroelectric thermal energy harvesting apparatus for generating an electric current includes a cantilevered layered pyroelectric capacitor extending between a first surface and a second surface, where the first surface includes a temperature difference from the second surface. The layered pyroelectric capacitor includes a conductive, bimetal top electrode layer, an intermediate pyroelectric dielectric layer and a conductive bottom electrode layer. In addition, a pair of proof masses is affixed at a distal end of the layered pyroelectric capacitor to face the first surface and the second surface, wherein the proof masses oscillate between the first surface and the second surface such that a pyroelectric current is generated in the pyroelectric capacitor due to temperature cycling when the proof masses alternately contact the first surface and the second surface.

  17. A Research Based on the metering and detecting Device for Industrial dispenser of non-contact technology

    Science.gov (United States)

    Chen, Xin; Li, Jingjing; Wang, Jingying

    2017-12-01

    Based on the non-contact detection technology, for the needs of on-site measurement for industrial dispenser, the dispenser device is designed and utilized non-contact laser measuring technology with high precision for measurement of length and speed to measure the coordination of displacement stroke and speed. According to “GBT 26799-2011 technical conditions for General Dispenser”, several key parameters are detected by comparing the experimental results, to meet the metering requirements of industrial dispenser.

  18. Preparation of electrodes on cfrp composites with low contact resistance comprising laser-based surface pre-treatment

    KAUST Repository

    Almuhammadi, Khaled Hamdan

    2016-12-29

    Various examples are provided related to the preparation of electrodes on carbon fiber reinforced polymer (CFRP) composites with low contact resistance. Laser-based surface preparation can be used for bonding to CFRP composites. In one example, a method includes preparing a pretreated target area on a CFRP composite surface using laser pulsed irradiation and bonding an electrode to exposed fibers in the pretreated target area. The surface preparation can allow the electrode to have a low contact resistance with the CFRP composite.

  19. Acoustic energy harvesting based on multilateral metasurfaces

    Science.gov (United States)

    Qi, Shuibao; Assouar, Badreddine

    2017-12-01

    We theoretically and numerically report on an innovative acoustic energy harvester based on acoustic multilateral metasurfaces and a piezoelectric bimorph. The coiling-up-space concept realized by labyrinthine units is applied to achieve the desired phase profiles for the acoustic focusing and energy confinement. The acoustic energy confined by the metasurfaces from a point source is converted into electrical energy by a structured piezoelectric bimorph. Numerical simulations and theoretical analysis evidenced that the output voltage and power drastically increase with the sides of the multilateral metasurface energy harvesting system. Maximum output voltage and power 52 and 407 times higher than those under the case without metasurfaces are achieved with enclosed multilateral metasurface design.

  20. The role of contact efficacy in evaluating sexual health promotion--evidence-based outreach work within a public sex environment.

    Science.gov (United States)

    Frankis, Jamie S; Flowers, Paul

    2006-05-01

    This paper explores the role of contact efficacy in evidence-based health promotion by evaluating a public sex environment (PSE) based sexual health outreach program. The service operated in situ from a dedicated mobile unit to promote sexual health among PSE users. A cross-sectional survey (response rate 56%) measured socio-demographics, sexual health behaviours and outreach-service use among men sampled within the PSE (n = 216). Most participants were aware of the service and two-thirds had contacted them. Men who had not completed hepatitis A vaccination (odds ratio (OR) = 2.02), who had ever received money for sex (OR = 2.07) or who reported a diagnosed mental health disorder(s) (OR = 2.38) were significantly more likely to have contacted the service. Although 89% of service users perceived the intervention positively, only 26% felt it had contributed to sexual behaviour changes. The 'mobile-unit' outreach model contacted a large proportion of PSE users, specifically men who had greater health needs. We advocate the adoption of this outreach model over traditional PSE-based outreach approaches. Contact efficacy evaluation is useful to assess ongoing health interventions. However, caution must be exerted when interpreting certain contact efficacy results. Since causality may not always be inferred, triangulation with other evaluative methodologies is recommended.

  1. Tariff based value of wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Raekkoelaeinen, J.; Vilkko, M.; Antila, H.; Lautala, P. [Tampere Univ. of Technology (Finland)

    1995-12-31

    In this article an approach for determining a value of wind energy is presented. Calculation is based on wholesale tariffs, i.e. the value of wind energy is defined in comparison with other purchase. This approach can be utilised as an aid in the investment planning in defining the benefits of new wind generation capacity. Linear programming optimization method is used. A case study is presented for different wind scenarios. The value of wind energy can vary remarkably depending on timing of power output. (author)

  2. Tariff based value of wind energy

    International Nuclear Information System (INIS)

    Raekkoelaeinen, J.; Vilkko, M.; Antila, H.; Lautala, P.

    1995-01-01

    In this article an approach for determining a value of wind energy is presented. Calculation is based on wholesale tariffs, i.e. the value of wind energy is defined in comparison with other purchase. This approach can be utilised as an aid in the investment planning in defining the benefits of new wind generation capacity. Linear programming optimization method is used. A case study is presented for different wind scenarios. The value of wind energy can vary remarkably depending on timing of power output. (author)

  3. Finite element based contact analysis of radio frequency MEMs switch membrane surfaces

    Science.gov (United States)

    Liu, Jin-Ya; Chalivendra, Vijaya; Huang, Wenzhen

    2017-10-01

    Finite element simulations were performed to determine the contact behavior of radio frequency (RF) micro-electro-mechanical (MEM) switch contact surfaces under monotonic and cyclic loading conditions. Atomic force microscopy (AFM) was used to capture the topography of RF-MEM switch membranes and later they were analyzed for multi-scale regular as well as fractal structures. Frictionless, non-adhesive contact 3D finite element analysis was carried out at different length scales to investigate the contact behavior of the regular-fractal surface using an elasto-plastic material model. Dominant micro-scale regular patterns were found to significantly change the contact behavior. Contact areas mainly cluster around the regular pattern. The contribution from the fractal structure is not significant. Under cyclic loading conditions, plastic deformation in the 1st loading/unloading cycle smooth the surface. The subsequent repetitive loading/unloading cycles undergo elastic contact without changing the morphology of the contacting surfaces. The work is expected to shed light on the quality of the switch surface contact as well as the optimum design of RF MEM switch surfaces.

  4. Efficient Regular Perovskite Solar Cells Based on Pristine [70]Fullerene as Electron-Selective Contact.

    Science.gov (United States)

    Collavini, Silvia; Kosta, Ivet; Völker, Sebastian F; Cabanero, German; Grande, Hans J; Tena-Zaera, Ramón; Delgado, Juan Luis

    2016-06-08

    [70]Fullerene is presented as an efficient alternative electron-selective contact (ESC) for regular-architecture perovskite solar cells (PSCs). A smart and simple, well-described solution processing protocol for the preparation of [70]- and [60]fullerene-based solar cells, namely the fullerene saturation approach (FSA), allowed us to obtain similar power conversion efficiencies for both fullerene materials (i.e., 10.4 and 11.4 % for [70]- and [60]fullerene-based devices, respectively). Importantly, despite the low electron mobility and significant visible-light absorption of [70]fullerene, the presented protocol allows the employment of [70]fullerene as an efficient ESC. The [70]fullerene film thickness and its solubility in the perovskite processing solutions are crucial parameters, which can be controlled by the use of this simple solution processing protocol. The damage to the [70]fullerene film through dissolution during the perovskite deposition is avoided through the saturation of the perovskite processing solution with [70]fullerene. Additionally, this fullerene-saturation strategy improves the performance of the perovskite film significantly and enhances the power conversion efficiency of solar cells based on different ESCs (i.e., [60]fullerene, [70]fullerene, and TiO2 ). Therefore, this universal solution processing protocol widens the opportunities for the further development of PSCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Automatic detection of measurement points for non-contact vibrometer-based diagnosis of cardiac arrhythmias

    Science.gov (United States)

    Metzler, Jürgen; Kroschel, Kristian; Willersinn, Dieter

    2017-03-01

    Monitoring of the heart rhythm is the cornerstone of the diagnosis of cardiac arrhythmias. It is done by means of electrocardiography which relies on electrodes attached to the skin of the patient. We present a new system approach based on the so-called vibrocardiogram that allows an automatic non-contact registration of the heart rhythm. Because of the contactless principle, the technique offers potential application advantages in medical fields like emergency medicine (burn patient) or premature baby care where adhesive electrodes are not easily applicable. A laser-based, mobile, contactless vibrometer for on-site diagnostics that works with the principle of laser Doppler vibrometry allows the acquisition of vital functions in form of a vibrocardiogram. Preliminary clinical studies at the Klinikum Karlsruhe have shown that the region around the carotid artery and the chest region are appropriate therefore. However, the challenge is to find a suitable measurement point in these parts of the body that differs from person to person due to e. g. physiological properties of the skin. Therefore, we propose a new Microsoft Kinect-based approach. When a suitable measurement area on the appropriate parts of the body are detected by processing the Kinect data, the vibrometer is automatically aligned on an initial location within this area. Then, vibrocardiograms on different locations within this area are successively acquired until a sufficient measuring quality is achieved. This optimal location is found by exploiting the autocorrelation function.

  6. Graphene-Based Systems for Energy Storage

    Science.gov (United States)

    Calle, Carlos I.; Mackey, Paul J.; Johansen, Michael R.; Phillips, James, III; Hogue, Michael; Kaner, Richard B.; El-Kady, Maher

    2016-01-01

    Development of graphene-based energy storage devices based on the Laser Scribe system developed by the University of California Los Angeles. These devices These graphene-based devices store charge on graphene sheets and take advantage of the large accessible surface area of graphene (2,600 m2g) to increase the electrical energy that can be stored. The proposed devices should have the electrical storage capacity of thin-film-ion batteries but with much shorter charge discharge cycle times as well as longer lives The proposed devices will be carbon-based and so will not have the same issues with flammability or toxicity as the standard lithium-based storage cells.

  7. Place-based social contact and mixing: a typology of generic meeting places of relevance for infectious disease transmission.

    Science.gov (United States)

    Strömgren, M; Holm, E; Dahlström, Ö; Ekberg, J; Eriksson, H; Spreco, A; Timpka, T

    2017-09-01

    This study aims to develop a typology of generic meeting places based on social contact and mixing of relevance for infectious disease transmission. Data were collected by means of a contact diary survey conducted on a representative sample of the Swedish population. The typology is derived from a cluster analysis accounting for four dimensions associated with transmission risk: visit propensity and its characteristics in terms of duration, number of other persons present and likelihood of physical contact. In the analysis, we also study demographic, socio-economic and geographical differences in the propensity of visiting meeting places. The typology identifies the family venue, the fixed activity site, the family vehicle, the trading plaza and the social network hub as generic meeting places. The meeting place typology represents a spatially explicit account of social contact and mixing relevant to infectious disease modelling, where the social context of the outbreak can be highlighted in light of the actual infectious disease.

  8. Geometry based finite element modeling of the electrical contact between a cultured neuron and a microelectrode

    NARCIS (Netherlands)

    Buitenweg, Jan R.; Rutten, Wim; Marani, Enrico

    2003-01-01

    The electrical contact between a substrate embedded microelectrode and a cultured neuron depends on the geometry of the neuron-electrode interface. Interpretation and improvement of these contacts requires proper modeling of all coupling mechanisms. In literature, it is common practice to model the

  9. Contact allergy to aliphatic polyisocyanates based on hexamethylene-1,6-diisocyanate (HDI).

    Science.gov (United States)

    Aalto-Korte, Kristiina; Pesonen, Maria; Kuuliala, Outi; Alanko, Kristiina; Jolanki, Riitta

    2010-12-01

    Aliphatic polyisocyanates based on hexamethylene 1,6-diisocyanate (HDI) are components of lacquers, coatings, and spray paints. They are mainly composed of HDI trimers, but also contain larger oligomers, and minute amounts of HDI monomers (paints. The patients were examined at the Finnish Institute of Occupational Health in 2000-2009. The first two patients were diagnosed by testing with their own polyurethane hardeners and ingredients of the hardeners. In 2002, HDI isocyanurate (HDI-IC) trimer was added to our isocyanate series, and the last two patients were screened with the series. Patient no. 1 was exposed and sensitized to HDI biuret trimer, patient no. 2 to HDI-IC trimer, and patient no. 4 to HDI asymmetrical trimer. Patient no. 3 was positive with HDI-IC trimer. He had been handling several paint hardeners containing HDI-based polyisocyanates, but the subtypes of the trimers remained unidentified. All 4 patients were negative with HDI monomer. HDI trimers are novel contact allergens in workers who handle polyurethane paints. The allergic reactions cannot be explained by sensitization to HDI monomer. © 2010 John Wiley & Sons A/S.

  10. Solid-contact potentiometric sensor for ascorbic acid based on cobalt phthalocyanine nanoparticles as ionophore.

    Science.gov (United States)

    Wang, Kun; Xu, Jing-Juan; Tang, Kai-Shi; Chen, Hong-Yuan

    2005-10-15

    A novel solid-contact potentiometric sensor for ascorbic acid based on cobalt phthalocyanine nanoparticles (NanoCoPc) as ionophore was fabricated without any need of auxiliary materials (such as membrane matrix, plasticizer, and other additives). The electrode was prepared by simple drop-coating NanoCoPc colloid on the surface of a glassy carbon electrode. A smooth, bright and blue thin film was strongly attached on the surface of the glassy carbon electrode. The electrode showed high selectivity for ascorbic acid, as compared with many common anions. The influences of the amount of NanoCoPc at the electrode surface and pH on the response characteristics of the electrode were investigated. To overcome the instability of the formal potential of the coated wire electrode, a novel electrochemical pretreatment method was proposed for the potentiometric sensor based on redox mechanism. This resulting sensor demonstrates potentiometric response over a wide linear range of ascorbic acid concentration (5.5 x 10(-7) to 5.5 x 10(-2)M) with a fast response (determination of practical samples.

  11. Self-powered, ultra-sensitive, flexible tactile sensors based on contact electrification

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhong Lin; Zhu, Guang

    2018-03-20

    A tactile sensor for sensing touch from a human finger includes a triboelectric layer and includes a material that becomes electrically charged after being in contact with the finger. The first side of a first conductive layer is in contact with the second side of triboelectric layer. The first side of a dielectric layer is in contact with the first conductive layer and the second side of the dielectric layer is in contact with a second conductive layer. When the triboelectric layer becomes electrically charged after being in contact with the finger, the first conductive layer and the second conductive layer are subjected to an electric field, which has a first field strength at the first conductive layer and a second field strength, different from the first field strength, at the second conductive layer. A plurality of tactile sensors can be arranged as a keyboard.

  12. Yield of facility-based verbal screening amongst household contacts of patients with multi-drug resistant tuberculosis in Pakistan

    Directory of Open Access Journals (Sweden)

    Ejaz Qadeer

    2017-05-01

    Full Text Available Background: Household contacts of multidrug-resistant tuberculosis (MDR-TB patients are at a high risk of getting infected with TB/MDR-TB, therefore symptomatic or vulnerable individuals should be screened and treated early. Methods: A cross-sectional study was conducted among household contacts of MDR-TB patients in three high-burden TB sites in Pakistan from July 2013 to June 2014. MDR-TB index patients were asked to provide a list of all members of their household and were asked whether any of them had TB symptoms such as productive cough, fever, weight loss and night sweat (“facility-based verbal screening”. Symptomatic contacts were defined as presumptive TB cases and were invited for investigations at the facility. Those who did not come were paid a home-visit. Confirmed TB/MDR-TB patients were registered in the nearest treatment facility. Results: Of 209 MDR-TB index patients, 1467 household contacts were identified and screened, 95 of them children < 5 years. Of these 172 (12% were symptomatic. Most common symptoms were cough 157 (91% and fever 107 (62%. 58 (34% presumptive TB contacts were not investigated. Of total contacts, 56 (3.8% were diagnosed with TB, among them 54(96% with MDR-TB and 2(4% with drug-susceptible-TB. The number needed to screen (NNS to identify a new MDR-TB case among adult household contacts was 27 and among presumptive adult and pediatric TB contacts was three. All 56 confirmed patients were registered for treatment. Conclusion: Screening household contacts of MDR-TB index cases may be considered a feasible and high yield option, in high-burden, low-resource settings within Pakistan. The number of presumptive TB contacts required to screen to identify a new MDR-TB case was unusually low, indicating an effective strategy that could easily be scaled-up. The screening and management of vulnerable adults and children living with patients having TB of any form is a major priority in the combined efforts

  13. Synchrotron based x-ray fluorescence microscopy confirms copper in the corrosion products of metals in contact with treated wood

    Science.gov (United States)

    Samuel L. Zelinka; Joseph E. Jakes; Grant T. Kirker; David Vine; Stefan Vogt

    2017-01-01

    Copper based waterborne wood preservatives are frequently used to extend the service life of wood products when subjected to frequent moisture exposure. While these copper based treatments protect the wood from fungal decay and insect attack, they increase the corrosion of metals embedded or in contact with the treated wood. Previous research has shown the most...

  14. Sustainable Urban Regeneration Based on Energy Balance

    Directory of Open Access Journals (Sweden)

    Sacha Silvester

    2012-07-01

    Full Text Available In this paper, results are reported of a technology assessment of the use and integration of decentralized energy systems and storage devices in an urban renewal area. First the general context of a different approach based on 'rethinking' and the incorporation of ongoing integration of coming economical and environmental interests on infrastructure, in relation to the sustainable urban development and regeneration from the perspective of the tripod people, technology and design is elaborated. However, this is at different scales, starting mainly from the perspective of the urban dynamics. This approach includes a renewed look at the ‘urban metabolism’ and the role of environmental technology, urban ecology and environment behavior focus. Second, the potential benefits of strategic and balanced introduction and use of decentralized devices and electric vehicles (EVs, and attached generation based on renewables are investigated in more detail in the case study of the ‘Merwe-Vierhaven’ area (MW4 in the Rotterdam city port in the Netherlands. In order to optimize the energy balance of this urban renewal area, it is found to be impossible to do this by tuning the energy consumption. It is more effective to change the energy mix and related infrastructures. However, the problem in existing urban areas is that often these areas are restricted to a few energy sources due to lack of available space for integration. Besides this, energy consumption in most cases is relatively concentrated in (existing urban areas. This limits the potential of sustainable urban regeneration based on decentralized systems, because there is no balanced choice regarding the energy mix based on renewables and system optimization. Possible solutions to obtain a balanced energy profile can come from either the choice to not provide all energy locally, or by adding different types of storage devices to the systems. The use of energy balance based on renewables as a

  15. Sustainable urban regeneration based on energy balance

    NARCIS (Netherlands)

    Van Timmeren, A.; Zwetsloot, J.; Brezet, H.; Silvester, S.

    2012-01-01

    In this paper, results are reported of a technology assessment of the use and integration of decentralized energy systems and storage devices in an urban renewal area. First the general context of a different approach based on 'rethinking' and the incorporation of ongoing integration of coming

  16. Contact materials for thermostable resistors on the base of Ni-Re alloy

    International Nuclear Information System (INIS)

    Yusipov, H.Yu.; Glasman, L.I.; Arskaya, E.P.; Lazarev, Eh.M.; Korotkov, N.A.

    1979-01-01

    Given are the electron diffraction analysis results and the operational characteristics of the contact materials, used in the heat-resistant thin-filmed resistors (TFR), made on the basis of the Ni-Re system alloy. The results are compared with the pure nickel. Operational tests of the thin-filmed resistors, having (NR10-VP) alloy contacts, showed that the departure of the resistors nominals is almost twice as small as that for the resistors, having pure nickel contacts. The use of this alloy permits to increase the thermal stability and durability of the TFRs, if they are used under extreme conditions

  17. The effect of physical contact on changes in fatigue markers following rugby union field-based training.

    Science.gov (United States)

    Roe, Gregory; Darrall-Jones, Joshua; Till, Kevin; Phibbs, Padraic; Read, Dale; Weakley, Jonathon; Rock, Andrew; Jones, Ben

    2017-07-01

    Repeated physical contact in rugby union is thought to contribute to post-match fatigue; however, no evidence exists on the effect of contact activity during field-based training on fatigue responses. Therefore, the purpose of this study was to examine the effect of contact during training on fatigue markers in rugby union players. Twenty academy rugby union players participated in the cross-over study. The magnitude of change in upper- and lower-body neuromuscular function (NMF), whole blood creatine kinase concentration [CK] and perception of well-being was assessed pre-training (baseline), immediately and 24 h post-training following contact and non-contact, field-based training. Training load was measured using mean heart rate, session rating of perceived exertion (sRPE) and microtechnology (Catapult Optimeye S5). The inclusion of contact during field-based training almost certainly increased mean heart rate (9.7; ±3.9%) and sRPE (42; ±29.2%) and resulted in likely and very likely greater decreases in upper-body NMF (-7.3; ±4.7% versus 2.7; ±5.9%) and perception of well-being (-8.0; ±4.8% versus  -3.4; ±2.2%) 24 h post-training, respectively, and almost certainly greater elevations in [CK] (88.2; ±40.7% versus 3.7; ±8%). The exclusion of contact from field-based training almost certainly increased running intensity (19.8; ±5%) and distance (27.5; ±5.3%), resulting in possibly greater decreases in lower-body NMF (-5.6; ±5.2% versus 2.3; ±2.4%). Practitioners should be aware of the different demands and fatigue responses of contact and non-contact, field-based training and can use this information to appropriately schedule such training in the weekly microcycle.

  18. A non-contact high resolution piezoelectric film based sensor for monitoring breathing during sleep

    Science.gov (United States)

    Johnston, Robert; Nakano, Katsuya; Fujita, Kento; Misaki, Shinya; Fujii, Hiroyuki; Misaki, Yukinori

    2017-07-01

    Currently, research for measuring human breathing during sleep is actively being conducted into using technologies that include piezoelectric, ultrasonic, microwave and infrared rays. But various problems have led to not many practical applications. As such, it was decided to develop a PVDF (PolyVinylidene DiFluoride) based non-contact high resolution sensor for monitoring a subject's breathing as they sleep. Development of the high resolution respiration sensor was possible through the use of PVDF piezoelectric film and the development of a new sensor configuration. Although there was already an existing respiration sensor research resulting product available, is weak signal strength made it very sensitive to noise and difficult to measure respiration accurately. As such, complicated circuits and signal processing were needed. A new high resolution breathing sensor was developed with greater signal strength and with just the use of some simple circuits and signal processing, was able to accurately measure subject breathing. Also due to the greater signal strength, it became possible to measure both heart rate and respiration rate simultaneously.

  19. Contact Angle Goniometer

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The FTA32 goniometer provides video-based contact angle and surface tension measurement. Contact angles are measured by fitting a mathematical expression...

  20. Corporate Consumer Contact API

    Data.gov (United States)

    General Services Administration — The data in the Corporate Consumer Contact API is based on the content you can find in the Corporate Consumer Contact listing in the Consumer Action Handbook (PDF)....

  1. A nanowire based triboelectric nanogenerator for harvesting water wave energy and its applications

    Science.gov (United States)

    Li, Xiaoyi; Tao, Juan; Zhu, Jing; Pan, Caofeng

    2017-07-01

    The ocean wave energy is one of the most promising renewable and clean energy sources for human life, which is the so-called "Blue energy." In this work, a nanowire based triboelectric nanogenerator was designed for harvesting wave energy. The nanowires on the surface of FEP largely raise the contacting area with water and also make the polymer film hydrophobic. The output can reach 10 μ A and 200 V. When combined with a capacitor, an infrared emitter, and a receiver, a self-powered wireless infrared system is fabricated, which can be used in the fields of communication and detecting.

  2. Utilization of solar energy for direct contact membrane distillation process: An experimental study for desalination of real seawater

    Energy Technology Data Exchange (ETDEWEB)

    Palanisami, Nallasamy; He, Ke; Moon, Il Shik [Sunchon National University, Suncheon (Korea, Republic of)

    2014-01-15

    Membrane distillation (MD), a non-isothermal membrane separation process, is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions by passing vapor through a hydrophobic microporous membrane when a temperature difference is established across it. We used three commercially available hydrophobic microporous membranes (C02, C07 and C12; based on the pore size 0.2, 0.7 and 1.2 µm respectively) for desalination via direct contact MD (DCMD). The effects of operating parameters on permeation flux were studied. In addition, the desalination of seawater by solar assisted DCMD process was experimentally investigated. First, using solar power only short-term (one day), successful desalination of real seawater was achieved without temperature control under the following conditions: feed inlet temperature 65.0 .deg. C, permeate inlet temperature 25.0 .deg. C, and a flow rate of 2.5 L/min. The developed system also worked well in the long-term (150 days) for seawater desalination using both solar and electric power. Long-term test flux was reduced from 28.48 to only 26.50 L/m{sup 2}hr, indicating system feasibility.

  3. Utilization of solar energy for direct contact membrane distillation process: An experimental study for desalination of real seawater

    International Nuclear Information System (INIS)

    Palanisami, Nallasamy; He, Ke; Moon, Il Shik

    2014-01-01

    Membrane distillation (MD), a non-isothermal membrane separation process, is based on the phenomenon that pure water in its vapor state can be extracted from aqueous solutions by passing vapor through a hydrophobic microporous membrane when a temperature difference is established across it. We used three commercially available hydrophobic microporous membranes (C02, C07 and C12; based on the pore size 0.2, 0.7 and 1.2 µm respectively) for desalination via direct contact MD (DCMD). The effects of operating parameters on permeation flux were studied. In addition, the desalination of seawater by solar assisted DCMD process was experimentally investigated. First, using solar power only short-term (one day), successful desalination of real seawater was achieved without temperature control under the following conditions: feed inlet temperature 65.0 .deg. C, permeate inlet temperature 25.0 .deg. C, and a flow rate of 2.5 L/min. The developed system also worked well in the long-term (150 days) for seawater desalination using both solar and electric power. Long-term test flux was reduced from 28.48 to only 26.50 L/m 2 hr, indicating system feasibility

  4. Synthesis, Characterization, and Evaluation of Ag-based Electrical Contact Materials

    OpenAIRE

    Mao, Fang

    2017-01-01

    Ag is a widely used electrical contact material due to its excellent electrical properties. The problems with Ag are that it is soft and has poor tribological properties (high friction and wear in Ag/Ag sliding contacts). For smart grid applications, friction and wear became increasingly important issues to be improved, due to much higher sliding frequency in the harsh operation environment. The aim of this thesis is to explore several different concepts to improve the properties of Ag electr...

  5. OPTIMIZATION OF THE TECHNOLOGY OF MANUFACTURE OF VARIATIONS WITH OMITTED CONTACTS BASED ON NI AND AL

    Directory of Open Access Journals (Sweden)

    Litvinenko V.M.

    2017-12-01

    Full Text Available The results of the study of the causes of degradation of inverse VAC of varicosity structures during formation of ohmic contacts on the basis of aluminum and nickel are presented. The data on the optimization of the formation of aluminum and nickel omic contacts through the use of operations of structural defect heatering are given. The technological regimes of creation of hetero domains on varikapnyh structures are resulted

  6. Energy Information Data Base: corporate author entries

    International Nuclear Information System (INIS)

    1980-06-01

    One of the controls for information entered into the data bases created and maintained by the DOE Technical Information Center is the standardized name for the corporate entity or the corporate author. The purpose of Energy Information Data Base: Corporate Author Entries is to provide a means for the consistent citing of the names of organizations in bibliographic records. These entries serve as guides for users of the DOE/RECON computerized data bases who want to locate information originating in particular organizations. The entries in this revision include the corporate entries used in report bibliographic citations since 1973 and list approximately 28,000 corporate sources

  7. Non-contact measurement of partial gas pressure and distribution of elemental composition using energy-resolved neutron imaging

    Science.gov (United States)

    Tremsin, A. S.; Losko, A. S.; Vogel, S. C.; Byler, D. D.; McClellan, K. J.; Bourke, M. A. M.; Vallerga, J. V.

    2017-01-01

    Neutron resonance absorption imaging is a non-destructive technique that can characterize the elemental composition of a sample by measuring nuclear resonances in the spectrum of a transmitted beam. Recent developments in pixelated time-of-flight imaging detectors coupled with pulsed neutron sources pose new opportunities for energy-resolved imaging. In this paper we demonstrate non-contact measurements of the partial pressure of xenon and krypton gases encapsulated in a steel pipe while simultaneously passing the neutron beam through high-Z materials. The configuration was chosen as a proof of principle demonstration of the potential to make non-destructive measurement of gas composition in nuclear fuel rods. The pressure measured from neutron transmission spectra (˜739 ± 98 kPa and ˜751 ± 154 kPa for two Xe resonances) is in relatively good agreement with the pressure value of ˜758 ± 21 kPa measured by a pressure gauge. This type of imaging has been performed previously for solids with a spatial resolution of ˜ 100 μm. In the present study it is demonstrated that the high penetration capability of epithermal neutrons enables quantitative mapping of gases encapsulate within high-Z materials such as steel, tungsten, urania and others. This technique may be beneficial for the non-destructive testing of bulk composition of objects (such as spent nuclear fuel assemblies and others) containing various elements opaque to other more conventional imaging techniques. The ability to image the gaseous substances concealed within solid materials also allows non-destructive leak testing of various containers and ultimately measurement of gas partial pressures with sub-mm spatial resolution.

  8. Non-contact measurement of partial gas pressure and distribution of elemental composition using energy-resolved neutron imaging

    Directory of Open Access Journals (Sweden)

    A. S. Tremsin

    2017-01-01

    Full Text Available Neutron resonance absorption imaging is a non-destructive technique that can characterize the elemental composition of a sample by measuring nuclear resonances in the spectrum of a transmitted beam. Recent developments in pixelated time-of-flight imaging detectors coupled with pulsed neutron sources pose new opportunities for energy-resolved imaging. In this paper we demonstrate non-contact measurements of the partial pressure of xenon and krypton gases encapsulated in a steel pipe while simultaneously passing the neutron beam through high-Z materials. The configuration was chosen as a proof of principle demonstration of the potential to make non-destructive measurement of gas composition in nuclear fuel rods. The pressure measured from neutron transmission spectra (∼739 ± 98 kPa and ∼751 ± 154 kPa for two Xe resonances is in relatively good agreement with the pressure value of ∼758 ± 21 kPa measured by a pressure gauge. This type of imaging has been performed previously for solids with a spatial resolution of ∼ 100 μm. In the present study it is demonstrated that the high penetration capability of epithermal neutrons enables quantitative mapping of gases encapsulate within high-Z materials such as steel, tungsten, urania and others. This technique may be beneficial for the non-destructive testing of bulk composition of objects (such as spent nuclear fuel assemblies and others containing various elements opaque to other more conventional imaging techniques. The ability to image the gaseous substances concealed within solid materials also allows non-destructive leak testing of various containers and ultimately measurement of gas partial pressures with sub-mm spatial resolution.

  9. Case study on water based cellulose couplant in contact type ultrasonic testing

    Directory of Open Access Journals (Sweden)

    Shivamurthy B.

    2018-01-01

    Full Text Available In this paper the ultrasonic test performance of water based Methylcellulose couplant on steel is reported. The couplant used in the ultrasonic testing has an influence on the amplitude of the pulse echo signal. The ultrasonic energy which is transmitted from the transducer to the test material, through the couplant which is present in the interface. The amplitudes of back wall echo increases with increasing acoustic impedance of the couplant. In this research work couplant was prepared by using 0 to 50g of methylcellulose in steps of 10g in 250 ml of water. All five types of water based methylcellulose couplant were used for testing a standard stainless steel calibration U2 block. The effect on the amplitudes of back wall echoes was studied and best possible combination of water and methylcellulose are reported.

  10. HMX based enhanced energy LOVA gun propellant.

    Science.gov (United States)

    Sanghavi, R R; Kamale, P J; Shaikh, M A R; Shelar, S D; Kumar, K Sunil; Singh, Amarjit

    2007-05-08

    Efforts to develop gun propellants with low vulnerability have recently been focused on enhancing the energy with a further improvement in its sensitivity characteristics. These propellants not only prevent catastrophic disasters due to unplanned initiation of currently used gun propellants (based on nitrate esters) but also realize enhanced energy levels to increase the muzzle velocity of the projectiles. Now, in order to replace nitroglycerine, which is highly sensitive to friction and impact, nitramines meet the requirements as they offer superior energy due to positive heat of formation, typical stoichiometry with higher decomposition temperatures and also owing to negative oxygen balance are less sensitive than stoichiometrically balanced NG. RDX has been widely reported for use in LOVA propellant. In this paper we have made an effort to present the work on scantily reported nitramine HMX based LOVA gun propellant while incorporating energetic plasticizer glycidyl azide polymer to enhance the energy level. HMX is known to be thermally stable at higher temperature than RDX and also proved to be less vulnerable to small scale shaped charge jet attack as its decomposition temperature is 270 degrees C. HMX also offers improved impulse due to its superior heat of formation (+17 kcal/mol) as compared to RDX (+14 kcal/mol). It has also been reported that a break point will not appear until 35,000 psi for propellant comprising of 5 microm HMX. Since no work has been reported in open literature regarding replacement of RDX by HMX, the present studies were carried out.

  11. Chair-based fidgeting and energy expenditure.

    Science.gov (United States)

    Koepp, Gabriel A; Moore, Graham K; Levine, James A

    2016-01-01

    Sedentariness is associated with chronic health conditions, impaired cognitive function and obesity. Work contributes significantly to sedentariness because many work tasks necessitate sitting. Few sustained solutions exist to reverse workplace sedentariness. Here, we evaluated a chair and an under-table device that were designed to promote fidgeting while seated. Our hypothesis was that an under-table leg-fidget bar and/or a fidget-promoting chair significantly increased energy expenditure. We compared these devices with chair-based exercise and walking. We measured energy expenditure and heart rate in 16 people while they sat and worked using a standard chair, an under-desk device that encourages leg fidgeting and a fidget-promoting chair. We compared outcomes with chair-based exercise and walking. Energy expenditure increased significantly while using either an under-table leg-fidget bar or a fidget-promoting chair, when compared to the standard office chair (standard chair, 76±31 kcal/hour; leg-fidget bar, 98±42 kcal/hour (pchair, 89±40 kcal/hour (p=0.03)). However, heart rate did not increase significantly in either case. Bouts of exercise performed while seated provided energetic and heart rate equivalency to walking at 2 mph. Chairs and devices that promote fidgeting can increase energy expenditure by ∼20-30% but not increase heart rate. Dynamic sitting may be among a lexicon of options to help people move more while at work.

  12. Virus-based piezoelectric energy generation

    Science.gov (United States)

    Lee, Byung Yang; Zhang, Jinxing; Zueger, Chris; Chung, Woo-Jae; Yoo, So Young; Wang, Eddie; Meyer, Joel; Ramesh, Ramamoorthy; Lee, Seung-Wuk

    2012-06-01

    Piezoelectric materials can convert mechanical energy into electrical energy, and piezoelectric devices made of a variety of inorganic materials and organic polymers have been demonstrated. However, synthesizing such materials often requires toxic starting compounds, harsh conditions and/or complex procedures. Previously, it was shown that hierarchically organized natural materials such as bones, collagen fibrils and peptide nanotubes can display piezoelectric properties. Here, we demonstrate that the piezoelectric and liquid-crystalline properties of M13 bacteriophage (phage) can be used to generate electrical energy. Using piezoresponse force microscopy, we characterize the structure-dependent piezoelectric properties of the phage at the molecular level. We then show that self-assembled thin films of phage can exhibit piezoelectric strengths of up to 7.8 pm V-1. We also demonstrate that it is possible to modulate the dipole strength of the phage, hence tuning the piezoelectric response, by genetically engineering the major coat proteins of the phage. Finally, we develop a phage-based piezoelectric generator that produces up to 6 nA of current and 400 mV of potential and use it to operate a liquid-crystal display. Because biotechnology techniques enable large-scale production of genetically modified phages, phage-based piezoelectric materials potentially offer a simple and environmentally friendly approach to piezoelectric energy generation.

  13. Energy-Based Analysis of Ultrasonically Assisted Turning

    Directory of Open Access Journals (Sweden)

    G.A. Volkov

    2011-01-01

    Full Text Available The process of ultrasonically-assisted turning (UAT is a superposition of vibration of a cutting tool on its standard movement in conventional turning (CT. The former technique has several advantages compared with the latter, one of the main being a significant decrease in the level of cutting forces. In this paper the effects observed in UAT are analysed employing ideas of dynamic fracture mechanics. The active stage of loading duration depends heavily on ultrasonic frequency and the cutting speed; he application of the fracture criterion based on the notion of incubation time makes it possible to calculate a dependence of this duration on its threshold amplitude. An estimation of energy, necessary to create a threshold pulse in the material, is made by solving the contact Hertz problem. The obtained time dependence of energy has a marked minimum. Thus, the existence of energy-efficient loading duration is demonstrated. This explains the decrease in the cutting force resulting from superimposed ultrasonic vibration. The obtained results are in agreement with experiments on ultrasonic assisted machining of aluminium and Inconel 718 alloy.

  14. Template-based and free modeling of I-TASSER and QUARK pipelines using predicted contact maps in CASP12.

    Science.gov (United States)

    Zhang, Chengxin; Mortuza, S M; He, Baoji; Wang, Yanting; Zhang, Yang

    2018-03-01

    We develop two complementary pipelines, "Zhang-Server" and "QUARK", based on I-TASSER and QUARK pipelines for template-based modeling (TBM) and free modeling (FM), and test them in the CASP12 experiment. The combination of I-TASSER and QUARK successfully folds three medium-size FM targets that have more than 150 residues, even though the interplay between the two pipelines still awaits further optimization. Newly developed sequence-based contact prediction by NeBcon plays a critical role to enhance the quality of models, particularly for FM targets, by the new pipelines. The inclusion of NeBcon predicted contacts as restraints in the QUARK simulations results in an average TM-score of 0.41 for the best in top five predicted models, which is 37% higher than that by the QUARK simulations without contacts. In particular, there are seven targets that are converted from non-foldable to foldable (TM-score >0.5) due to the use of contact restraints in the simulations. Another additional feature in the current pipelines is the local structure quality prediction by ResQ, which provides a robust residue-level modeling error estimation. Despite the success, significant challenges still remain in ab initio modeling of multi-domain proteins and folding of β-proteins with complicated topologies bound by long-range strand-strand interactions. Improvements on domain boundary and long-range contact prediction, as well as optimal use of the predicted contacts and multiple threading alignments, are critical to address these issues seen in the CASP12 experiment. © 2017 Wiley Periodicals, Inc.

  15. A Solid-Contact Indium(III) Sensor based on a Thiosulfinate Ionophore Derived from Omeprazole

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Mohammad Nooredeen; Hend Samy Amer [National Research Centre, Cairo (Egypt)

    2013-04-15

    A novel solid-contact indium(III)-selective sensor based on bis-(1H-benzimidazole-5-methoxy-2-[(4-methoxy-3, 5-dimethyl-1-pyridinyl) 2-methyl]) thiosulfinate, known as an omeprazole dimer (OD) and a neutral ionophore, was constructed, and its performance characteristics were evaluated. The sensor was prepared by applying a membrane cocktail containing the ionophore to a graphite rod pre-coated with polyethylene dioxythiophene (PEDOT) conducting polymer as the ion-to-electron transducer. The membrane contained 3.6% OD, 2.3% oleic acid (OA) and 62% dioctyl phthalate (DOP) as the solvent mediator in PVC and produced a good potentiometric response to indium(III) ions with a Nernstian slope of 19.09 mV/decade. The constructed sensor possessed a linear concentration range from 3 Χ 10{sup -7} to 1 Χ 10{sup -2} M and a lower detection limit (LDL) of 1 Χ 10{sup -7} M indium(III) over a pH range of 4.0-7.0. It also displayed a fast response time and good selectivity for indium(III) over several other ions. The sensor can be used for longer than three months without any considerable divergence in potential. The sensor was utilized for direct and flow injection potentiometric (FIP) determination of indium(III) in alloys. The parameters that control the flow injection method were optimized. Indium(III) was quantitatively recovered, and the results agreed with those obtained using atomic absorption spectrophotometry, as confirmed by the f and t values. The sensor was also utilized as an indicator electrode for the potentiometric titration of fluoride in the presence of chloride, bromide, iodide and thiocyanate ions using indium(III) nitrate as the titrant.

  16. A Solid-Contact Indium(III) Sensor based on a Thiosulfinate Ionophore Derived from Omeprazole

    International Nuclear Information System (INIS)

    Abbas, Mohammad Nooredeen; Hend Samy Amer

    2013-01-01

    A novel solid-contact indium(III)-selective sensor based on bis-(1H-benzimidazole-5-methoxy-2-[(4-methoxy-3, 5-dimethyl-1-pyridinyl) 2-methyl]) thiosulfinate, known as an omeprazole dimer (OD) and a neutral ionophore, was constructed, and its performance characteristics were evaluated. The sensor was prepared by applying a membrane cocktail containing the ionophore to a graphite rod pre-coated with polyethylene dioxythiophene (PEDOT) conducting polymer as the ion-to-electron transducer. The membrane contained 3.6% OD, 2.3% oleic acid (OA) and 62% dioctyl phthalate (DOP) as the solvent mediator in PVC and produced a good potentiometric response to indium(III) ions with a Nernstian slope of 19.09 mV/decade. The constructed sensor possessed a linear concentration range from 3 Χ 10 -7 to 1 Χ 10 -2 M and a lower detection limit (LDL) of 1 Χ 10 -7 M indium(III) over a pH range of 4.0-7.0. It also displayed a fast response time and good selectivity for indium(III) over several other ions. The sensor can be used for longer than three months without any considerable divergence in potential. The sensor was utilized for direct and flow injection potentiometric (FIP) determination of indium(III) in alloys. The parameters that control the flow injection method were optimized. Indium(III) was quantitatively recovered, and the results agreed with those obtained using atomic absorption spectrophotometry, as confirmed by the f and t values. The sensor was also utilized as an indicator electrode for the potentiometric titration of fluoride in the presence of chloride, bromide, iodide and thiocyanate ions using indium(III) nitrate as the titrant

  17. Non-contact Real-time heart rate measurements based on high speed circuit technology research

    Science.gov (United States)

    Wu, Jizhe; Liu, Xiaohua; Kong, Lingqin; Shi, Cong; Liu, Ming; Hui, Mei; Dong, Liquan; Zhao, Yuejin

    2015-08-01

    In recent years, morbidity and mortality of the cardiovascular or cerebrovascular disease, which threaten human health greatly, increased year by year. Heart rate is an important index of these diseases. To address this status, the paper puts forward a kind of simple structure, easy operation, suitable for large populations of daily monitoring non-contact heart rate measurement. In the method we use imaging equipment video sensitive areas. The changes of light intensity reflected through the image grayscale average. The light change is caused by changes in blood volume. We video the people face which include the sensitive areas (ROI), and use high-speed processing circuit to save the video as AVI format into memory. After processing the whole video of a period of time, we draw curve of each color channel with frame number as horizontal axis. Then get heart rate from the curve. We use independent component analysis (ICA) to restrain noise of sports interference, realized the accurate extraction of heart rate signal under the motion state. We design an algorithm, based on high-speed processing circuit, for face recognition and tracking to automatically get face region. We do grayscale average processing to the recognized image, get RGB three grayscale curves, and extract a clearer pulse wave curves through independent component analysis, and then we get the heart rate under the motion state. At last, by means of compare our system with Fingertip Pulse Oximeter, result show the system can realize a more accurate measurement, the error is less than 3 pats per minute.

  18. Electrical properties of nanosized non-barrier inhomogeneities in Zn-based metal-semiconductor contacts to InP

    DEFF Research Database (Denmark)

    Clausen, Thomas; Leistiko, Otto

    1998-01-01

    We have found that the electrical properties of carriers across the metal-semiconductor interface for alloyed Zn based metallizations to n- and p-InP are dominated by nanosized non-barrier inhomogeneities. The effective area covered by the nanosized regions is a small fraction of the contact area...... resulting in high values of the specific contact resistance to p-InP. For n(-)-InP, thermionic emission across nanosized inhomogeneities dominates the carrier flow when T-ann > 440 degrees C. (C) 1998 Elsevier Science B.V....

  19. Unified Analysis of Multi-Chamber Contact Tanks and Mixing Efficiency Evaluation Based on Vorticity Field. Part II: Transport Analysis

    Directory of Open Access Journals (Sweden)

    Ender Demirel

    2016-11-01

    Full Text Available Mixing characteristics of multi-chambered contact tank are analyzed employing the validated three-dimensional numerical model developed in the companion paper. Based on the flow characterization, novel volumetric mixing efficiency definitions are proposed for the assessment of the hydrodynamic and chemical transport properties of the contact tank and its chambers. Residence time distribution functions are analyzed not only at the outlet of each chamber but also inside the chambers using the efficiency definitions for both Reynolds averaged Navier–Stokes (RANS and large eddy simulation (LES results. A novel tracer mixing index is defined to characterize short circuiting and mixing effects of the contact system. Comparisons of the results of these indexes for RANS and LES solutions indicate that mixing characteristics are stronger in LES due to the unsteady turbulent eddy mixing even though short circuiting effects are also more prominent in LES results. This result indicates that the mixing analysis based on the LES results simulates the mixing characteristics instantaneously, which is more realistic than that in RANS. Since LES analysis can capture turbulent eddy mixing better than RANS analysis, the interaction of recirculation and jet zones are captured more effectively in LES, which tends to predict higher turbulent mixing in the contact system. The analysis also shows that the mixing efficiency of each chamber of the contact tank is different, thus it is necessary to consider distinct chemical release and volumetric designs for each chamber in order to maximize the mixing efficiency of the overall process in a contact tank system.

  20. COMSAT: Residue contact prediction of transmembrane proteins based on support vector machines and mixed integer linear programming.

    Science.gov (United States)

    Zhang, Huiling; Huang, Qingsheng; Bei, Zhendong; Wei, Yanjie; Floudas, Christodoulos A

    2016-03-01

    In this article, we present COMSAT, a hybrid framework for residue contact prediction of transmembrane (TM) proteins, integrating a support vector machine (SVM) method and a mixed integer linear programming (MILP) method. COMSAT consists of two modules: COMSAT_SVM which is trained mainly on position-specific scoring matrix features, and COMSAT_MILP which is an ab initio method based on optimization models. Contacts predicted by the SVM model are ranked by SVM confidence scores, and a threshold is trained to improve the reliability of the predicted contacts. For TM proteins with no contacts above the threshold, COMSAT_MILP is used. The proposed hybrid contact prediction scheme was tested on two independent TM protein sets based on the contact definition of 14 Å between Cα-Cα atoms. First, using a rigorous leave-one-protein-out cross validation on the training set of 90 TM proteins, an accuracy of 66.8%, a coverage of 12.3%, a specificity of 99.3% and a Matthews' correlation coefficient (MCC) of 0.184 were obtained for residue pairs that are at least six amino acids apart. Second, when tested on a test set of 87 TM proteins, the proposed method showed a prediction accuracy of 64.5%, a coverage of 5.3%, a specificity of 99.4% and a MCC of 0.106. COMSAT shows satisfactory results when compared with 12 other state-of-the-art predictors, and is more robust in terms of prediction accuracy as the length and complexity of TM protein increase. COMSAT is freely accessible at http://hpcc.siat.ac.cn/COMSAT/. © 2016 Wiley Periodicals, Inc.

  1. a-Si:H/c-Si heterojunction front- and back contacts for silicon solar cells with p-type base

    Energy Technology Data Exchange (ETDEWEB)

    Rostan, Philipp Johannes

    2010-07-01

    This thesis reports on low temperature amorphous silicon back and front contacts for high-efficiency crystalline silicon solar cells with a p-type base. The back contact uses a sequence of intrinsic amorphous (i-a-Si:H) and boron doped microcrystalline (p-{mu}c-Si:H) silicon layers fabricated by Plasma Enhanced Chemical Vapor Deposition (PECVD) and a magnetron sputtered ZnO:Al layer. The back contact is finished by evaporating Al onto the ZnO:Al and altogether prepared at a maximum temperature of 220 C. Analysis of the electronic transport of mobile charge carriers at the back contact shows that the two high-efficiency requirements low back contact series resistance and high quality c-Si surface passivation are in strong contradiction to each other, thus difficult to achieve at the same time. The preparation of resistance- and effective lifetime samples allows one to investigate both requirements independently. Analysis of the majority charge carrier transport on complete Al/ZnO:Al/a-Si:H/c-Si back contact structures derives the resistive properties. Measurements of the effective minority carrier lifetime on a-Si:H coated wafers determines the back contact surface passivation quality. Both high-efficiency solar cell requirements together are analyzed in complete photovoltaic devices where the back contact series resistance mainly affects the fill factor and the back contact passivation quality mainly affects the open circuit voltage. The best cell equipped with a diffused emitter with random texture and a full-area a-Si:H/c-Si back contact has an independently confirmed efficiency {eta} = 21.0 % with an open circuit voltage V{sub oc} = 681 mV and a fill factor FF = 78.7 % on an area of 1 cm{sup 2}. An alternative concept that uses a simplified a-Si:H layer sequence combined with Al-point contacts yields a confirmed efficiency {eta} = 19.3 % with an open circuit voltage V{sub oc} = 655 mV and a fill factor FF = 79.5 % on an area of 2 cm{sup 2}. Analysis of the

  2. Speckle-based off-axis holographic detection for non-contact photoacoustic tomography

    Directory of Open Access Journals (Sweden)

    Buj C.

    2015-09-01

    Full Text Available A very fast innovative holographic off-axis non-contact detection method for Photoacoustic Tomography (PAT is introduced. It overcomes the main problems of most state-of-the-art photoacoustic imaging approaches that are long acquisition times and the requirement of acoustic contact. In order to increase the acquisition speed significantly, the surface displacements of the object, caused by the photoacoustic pressure waves, are measured interferometrically in two dimensions. Phase alterations in the observed speckle field are used to identify changes in the object’s topography. A sampling rate of up to 80 MHz is feasible, which reduces the occurrence of motion artefacts.

  3. Using net energy output as the base to develop renewable energy

    International Nuclear Information System (INIS)

    Shaw Daigee; Hung Mingfeng; Lin Yihao

    2010-01-01

    In order to increase energy security, production of renewable energies has been highly promoted by governments around the world in recent years. The typical base of various policy instruments used for this purpose is gross energy output of renewable energy. However, we show that basing policy instruments on gross energy output will result in problems associated with energy waste, economic inefficiency, and negative environmental effects. We recommend using net energy output as the base to apply price or quantity measures because it is net energy output, not gross energy output, which contributes to energy security. The promotion of gross energy output does not guarantee a positive amount of net energy output. By basing policy instruments on net energy output, energy security can be enhanced and the above mentioned problems can be avoided.

  4. Web-Based Treatment Program Using Intensive Therapeutic Contact for Patients With Eating Disorders: Before-After Study

    OpenAIRE

    ter Huurne, Elke D; Postel, Marloes G; de Haan, Hein A; Drossaert, Constance H.C; DeJong, Cor A.J

    2013-01-01

    Background: Although eating disorders are common in the Netherlands, only a few patients are treated by mental health care professionals. To reach and treat more patients with eating disorders, Tactus Addiction Treatment developed a web-based treatment program with asynchronous and intensive personalized communication between the patient and the therapist. Objective: This pilot study evaluated the web-based treatment program using intensive therapeutic contact in a population of 165 patients ...

  5. Smart-phone based computational microscopy using multi-frame contact imaging on a fiber-optic array.

    Science.gov (United States)

    Navruz, Isa; Coskun, Ahmet F; Wong, Justin; Mohammad, Saqib; Tseng, Derek; Nagi, Richie; Phillips, Stephen; Ozcan, Aydogan

    2013-10-21

    We demonstrate a cellphone based contact microscopy platform, termed Contact Scope, which can image highly dense or connected samples in transmission mode. Weighing approximately 76 grams, this portable and compact microscope is installed on the existing camera unit of a cellphone using an opto-mechanical add-on, where planar samples of interest are placed in contact with the top facet of a tapered fiber-optic array. This glass-based tapered fiber array has ~9 fold higher density of fiber optic cables on its top facet compared to the bottom one and is illuminated by an incoherent light source, e.g., a simple light-emitting-diode (LED). The transmitted light pattern through the object is then sampled by this array of fiber optic cables, delivering a transmission image of the sample onto the other side of the taper, with ~3× magnification in each direction. This magnified image of the object, located at the bottom facet of the fiber array, is then projected onto the CMOS image sensor of the cellphone using two lenses. While keeping the sample and the cellphone camera at a fixed position, the fiber-optic array is then manually rotated with discrete angular increments of e.g., 1-2 degrees. At each angular position of the fiber-optic array, contact images are captured using the cellphone camera, creating a sequence of transmission images for the same sample. These multi-frame images are digitally fused together based on a shift-and-add algorithm through a custom-developed Android application running on the smart-phone, providing the final microscopic image of the sample, visualized through the screen of the phone. This final computation step improves the resolution and also removes spatial artefacts that arise due to non-uniform sampling of the transmission intensity at the fiber optic array surface. We validated the performance of this cellphone based Contact Scope by imaging resolution test charts and blood smears.

  6. Passivating electron contact based on highly crystalline nanostructured silicon oxide layers for silicon solar cells

    Czech Academy of Sciences Publication Activity Database

    Stuckelberger, J.; Nogay, G.; Wyss, P.; Jeangros, Q.; Allebe, Ch.; Debrot, F.; Niquille, X.; Ledinský, Martin; Fejfar, Antonín; Despeisse, M.; Haug, F.J.; Löper, P.; Ballif, C.

    2016-01-01

    Roč. 158, Dec (2016), s. 2-10 ISSN 0927-0248 R&D Projects: GA MŠk LM2015087 Institutional support: RVO:68378271 Keywords : surface passivation * passivating contact * nanostructure * silicon oxide * nanocrystalline * microcrystalline * poly-silicon * crystallization * Raman * transmission line measurement Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 4.784, year: 2016

  7. Normal and friction stabilization techniques for interactive rigid body constraint-based contact force computations

    DEFF Research Database (Denmark)

    Silcowitz-Hansen, Morten; Abel, Sarah Maria Niebe; Erleben, Kenny

    2010-01-01

    We present a novel, yet simple, method for stabilization of normal forces. A normal stabilization term, carefully designed from hypotheses about interactive usability, is added to the contact force problem. Further, we propose friction stabilization as a completely new stabilization paradigm in i...

  8. AFM-based tribological study of nanopatterned surfaces: the influence of contact area instabilities.

    Science.gov (United States)

    Rota, A; Serpini, E; Gazzadi, G C; Valeri, S

    2016-04-06

    Although the importance of morphology on the tribological properties of surfaces has long been proved, an exhaustive understanding of nanopatterning effects is still lacking due to the difficulty in both fabricating 'really nano-' structures and detecting their tribological properties. In the present work we show how the probe-surface contact area can be a critical parameter due to its remarkable local variability, making a correct interpretation of the data very difficult in the case of extremely small nanofeatures. Regular arrays of parallel 1D straight nanoprotrusions were fabricated by means of a low-dose focused ion beam, taking advantage of the amorphization-related swelling effect. The tribological properties of the patterns were detected in the presence of air and in vacuum (dry ambient) by atomic force microscopy. We have introduced a novel procedure and data analysis to reduce the uncertainties related to contact instabilities. The real time estimation of the radius of curvature of the contacting asperity enables us to study the dependence of the tribological properties of the patterns from their geometrical characteristics. The effect of the patterns on both adhesion and the coefficient of friction strongly depends on the contact area, which is linked to the local radius of curvature of the probe. However, a detectable hydrophobic character induced on the hydrophilic native SiO2 has been observed as well. The results suggest a scenario for capillary formation on the patterns.

  9. Total FETI based algorithm for contact problems with additional non-linearities

    Czech Academy of Sciences Publication Activity Database

    Dobiáš, Jiří; Pták, Svatopluk; Dostál, Z.; Vondrák, V.

    2010-01-01

    Roč. 41, č. 1 (2010), s. 46-51 ISSN 0965-9978 R&D Projects: GA ČR GA101/05/0423 Institutional research plan: CEZ:AV0Z20760514 Keywords : contact problem * finite element method * domain decomposition Subject RIV: JC - Computer Hardware ; Software Impact factor: 1.004, year: 2010

  10. Experimentally-based optimization of contact parameters in dynamics simulation of humanoid robots

    NARCIS (Netherlands)

    Vivian, Michele; Reggiani, Monica; Sartori, Massimo

    2013-01-01

    With this work we introduce a novel methodology for the simulation of walking of a humanoid robot. Motion capture technology is used to calibrate the dynamics engine internal parameters and validate the simulated motor task. Results showed the calibrated contact model allows predicting dynamically

  11. COMMUNITY BASED HOME ENERGY MANAGEMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    Muhammad Adnan Aziz

    2017-05-01

    Full Text Available In a Smart Grid (SG scenario, domestic consumers can gain cost reduction benefit by scheduling their Appliance Activation Time (AAT towards the slots of low charge. Minimization in cost is essential in Home Energy Management Systems (HEMS to induce consumers acceptance for power scheduling to accommodate for a Demand Response (DR at peak hours. Despite the fact that many algorithms address the power scheduling for HEMS, community based optimization has not been the focus. This paper presents an algorithm that targets the minimization of energy costs of whole community while keeping a low Peak to Average Ratio (PAR and smooth Power Usage Pattern (PUP. Objective of cost reduction is accomplished by finding most favorable AAT by Particle Swarm Optimization (PSO in conjunction with Inclined Block Rate (IBR approach and Circular Price Shift (CPS. Simulated numerical results demonstrate the effectiveness of CPS to assist the merger of PSO & IBR to enhance the reduction/stability of PAR and cost reduction.

  12. Energy Data Base: subject categories and scope

    International Nuclear Information System (INIS)

    Bost, D.E.

    1985-03-01

    The subject scope of the Energy Data Base (EDB) encompasses all DOE-sponsored research. Broadly defined, EDB subject scope includes all technological aspects of energy production, conversion, and efficient utilization, and the economic, social, and political aspects as well. Scope notes are provided to define the extent of interest in certain subject areas, particularly areas of basic research. Cross references between categories are provided to aid both the categorization of information and its retrieval. Citations entered into DOE's computerized bibliographic information system are assigned six-digit subject category numbers to broadly group information for storage, retrieval, and manipulation. These numbers are used in the preparation of printed documents, such as bibliographies and abstract journals, to arrange the citations and to aid searching on the DOE/RECON on-line system

  13. Contact ion pair formation between hard acids and soft bases in aqueous solutions observed with 2DIR spectroscopy.

    Science.gov (United States)

    Sun, Zheng; Zhang, Wenkai; Ji, Minbiao; Hartsock, Robert; Gaffney, Kelly J

    2013-12-12

    The interaction of charged species in aqueous solution has important implications for chemical, biological, and environmental processes. We have used 2DIR spectroscopy to study the equilibrium dynamics of thiocyanate chemical exchange between free ion (NCS(-)) and contact ion pair configurations (MNCS(+)), where M(2+) = Mg(2+) or Ca(2+). Detailed studies of the influence of anion concentration and anion speciation show that the chemical exchange observed with the 2DIR measurements results from NCS(-) exchanging with other anion species in the first solvation shell surrounding Mg(2+) or Ca(2+). The presence of chemical exchange in the 2DIR spectra provides an indirect, but robust, determinant of contact ion pair formation. We observe preferential contact ion pair formation between soft Lewis base anions and hard Lewis acid cations. This observation cannot be easily reconciled with Pearson's acid-base concept or Collins' Law of Matching Water Affinities. The anions that form contact ion pairs also correspond to the ions with an affinity for water and protein surfaces, so similar physical and chemical properties may control these distinct phenomena.

  14. Energy Information Data Base: corporate author entries

    International Nuclear Information System (INIS)

    1980-03-01

    One of the controls for information entered into the data bases created and maintained by the DOE Technical Information Center is the standardized name for the corporate entity or the corporate author. The purpose of Energy Information Data Base: Corporate Author Entries (TID-4585-R1) and this supplemental list of authorized or standardized corporate entries is to provide a means for the consistent citing of the names of organizations in bibliographic records. In general, an entry in Corporate Author Entries consists of the seven-digit code number assigned to the particular corporate entity, the two-letter country code, the largest element of the corporate name, the location of the corporate entity, and the smallest element of the corporate name (if provided). This supplement [DOE/TIC-4585-R1(Suppl.5)] contains additions to the base document (TID-4585-R1) and is intended to be used with that publication

  15. Process for production of electrical energy from the neutralization of acid and base in a bipolar membrane cell

    International Nuclear Information System (INIS)

    Walther, J.F.

    1982-01-01

    Electrical energy is generated from acid-base neutralization reactions in electrodialytic cells. Permselective bipolar membranes in these cells are contacted on their cation selective faces by aqueous acid streams and on their anion-selective faces by aqueous base streams. Spontaneous neutralization reactions between the basic anions and acidic cations through the bipolar membranes produce electrical potential differences between the acid and base streams. These potential differences are transmitted to electrodes to produce electrical energy which is withdrawn from the cell

  16. Energy-based dynamic reliability analysis

    International Nuclear Information System (INIS)

    Fukushima, S.; Mizutani, M.; Akao, Y.; Katukura, H.

    1993-01-01

    Dynamic reliability analysis (DRA) of structures subjected to strong ground motions is one of the most important parts of the safety assessment of structures. So far many DRA methods based on probabilistic theory have been developed. Generally, DRA methods are divided into three phases; seismic hazard analysis, fragility synthesis, and evaluation of probability of failure. In most DRA method, the seismic hazard curves of peak ground acceleration (PGA) or spectral acceleration at a certain period is evaluated to show the occurrence ratio of input motion in the seismic hazard analysis, and, in the fragility synthesis, random vibration theory is adopted to calculate the conditional probability of failure of structures given the occurrence of input motion. Since random vibration theory is developed in the frequency domain, PGAs are transformed into information in the frequency domain by means of introducing so-called peak factors and power spectra. This fact suggests that it is more convenient for DRA researchers to define the seismic hazardous the indices defined in the frequency domain from the first. In this paper, DRAs based on the two indices, i.e. PGA and total energy, are investigated in detail. Through the study, features and issues of DRA based on the total energy (hereafter called EDRA) are clarified from the viewpoint of the responses of the structure. (author)

  17. Performance improvement inpolymer-based thin film transistor using modified bottom-contact structures with etched SiO{sub 2} layers

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Woo [R and D Center, Samsung Corning Precision Materials Co., Ltd, Asan (Korea, Republic of); You, Young Jun; Shim, Jae Won [Dept. of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul (Korea, Republic of)

    2017-02-15

    Polymer-based thin film transistors (TFTs) with a modified bottom-contact structure and etched SiO{sub 2} layer were developed and investigated. An increase in the field-effect mobility in the developed TFTs compared to TFTs with a normal bottom-contact structure was ascertained. A bottom-contact structure and the photolithographic processing method were used to ensure that the developed TFTs were suitable for commercial applications. Increased mobility of the modified bottom-contact structure was attributed to direct contact of the Au electrode with the active polymer layer.

  18. Silver-based contact materials - microstructure and mechanical properties; Kontaktwerkstoffe auf Silberbasis - Gefuege und mechanische Eigenschaften

    Energy Technology Data Exchange (ETDEWEB)

    Wielage, B.; Steger, H.; Podlesak, H.; Lampke, T. [TU Chemnitz (Germany). Institut fuer Werkstoffwissenschaft und Werkstofftechnik

    2008-12-15

    Different silver-based materials have been used in relays and contactors. Silver-based composite materials in particular have played an important role. To produce such composite materials on an industrial scale, conventional powder mixing and wet-chemical methods are used. By means of the powder-metallurgical route, these materials are processed in a second step into wire material. To produce silver-based composite materials with a comparable microstructure, the usability of alternative production routes was tested. This article shows the potential of the methods high-energy ball milling (HEM) and intensive mixing compared to the two above-named conventional methods. The main focus is on the evaluation of the microstructure of the composite powder and the extrusion wires concerning the dispersion of the reinforcement component and the resulting mechanical properties of the wire material. (Abstract Copyright [2008], Wiley Periodicals, Inc.) [German] Als Schalter-Kontaktwerkstoffe fuer Relais und Schuetze werden verschiedene Silberbasiswerkstoffe eingesetzt. Dabei kommt den Silberbasis-Verbundwerkstoffen eine besondere Bedeutung zu. Zur Herstellung dieser Verbundwerkstoffe im Industriemassstab werden aktuell die konventionellen Verfahren Pulvermischen und Nasschemisches Faellen in Verbindung mit der anschliessenden pulvermetallurgischen Verarbeitung zu Draehten angewendet. Zur Herstellung der Silberbasis-Verbundwerkstoffe mit vergleichbarem Gefuege wird die Eignung von alternativen Herstellungsrouten geprueft. Der vorliegende Beitrag zeigt das Potenzial der Verfahren Hochenergiekugelmahlen und Intensivmischen gegenueber den beiden ueblichen Verfahren auf. Das Hauptaugenmerk liegt auf der Beurteilung des Gefueges von Verbundpulver und Strangpressdraht hinsichtlich der Verteilung der Verstaerkungskomponente und der resultierenden mechanischen Eigenschaften des Drahtmaterials. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  19. An Investigation of a New Social Networks Contact Suggestion Based on Face Recognition Algorithm

    Directory of Open Access Journals (Sweden)

    Ivan Zelinka

    2016-01-01

    Full Text Available Automated comparison of faces in the photographs is a well established discipline. The main aim of this paper is to describe an approach whereby face recognition can be used in suggestion of a new contacts. The new contact suggestion is a common technique used across all main social networks. Our approach uses a freely available face comparison called "Betaface" together with our automated processig of the user´s Facebook profile. The research´s main point of interest is the comparison of friend´s facial images in a social network itself, how to process such a great amount of photos and what additional sources of data should be used. In this approach we used our automated processing algorithm Betaface in the social network Facebook and for the additional data, the Flickr social network was used. The results and their quality are discussed at the end.

  20. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.; Hagstroem, M.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The main technical constraint in solar energy systems which operate around the year is the lack of suitable long-term energy storage. Conventional solutions to overcome the problem of seasonal storage in PV power systems are to use oversized batteries as a seasonal energy storage, or to use a diesel back-up generator. However, affordable lead-acid batteries are not very suitable for seasonal energy storage because of a high self-discharge rate and enhanced deterioration and divergence of the single cells during prolonged periods of low state of charge in times of low irradiation. These disadvantages can be avoided by a back-up system, e.g. a diesel generator, which car supply energy to the loads and charge the battery to the full state of charge to avoid the above mentioned disadvantages. Unfortunately, diesel generators have several disadvantages, e.g. poor starting reliability, frequent need for maintenance and noise

  1. Study on the contact ratio of base mat of reactor buildings considering nonlinear soil-structure interaction effects

    International Nuclear Information System (INIS)

    Aihara, S.; Atsumi, K.; Ujiie, K.; Emori, K.; Odajima, M.; Masuda, K.

    1983-01-01

    The objective of this paper is to evaluate the nonlinear soil-structure interaction effects resulting from base mat uplift for static lateral loads. Nonlinear soil-structure interaction effects are modeled through the use of equivalent soil-structure interaction frictional and axial springs, which properties are determined by results of experimental data. It is assumed that normal stresses in compression and corresponding shear stresses, and friction, can occur in the area of contact between the embedded structure and soil. The remaining parts of the structure and soil are based on elastic analysis. A two-dimensional finite element method with incremental loadings is applied. The substructuring technique is used to reduce computation time. The results of this method with respect to the contact ratio of the base mat are compared with the values obtained by static elastic calculation which is simply derived from an overturning moment and a vertical load of the structure. This analytical concept will be developed into dynamic problems, and then it will be possible to state whether or not this concept can represent a true alternative for the contact ratio of the base mat of a structure. (orig./HP)

  2. Value of the energy data base

    Energy Technology Data Exchange (ETDEWEB)

    King, D.W.; Griffiths, J.M.; Roderer, N.K.; Wiederkehr, R.R.V.

    1982-03-31

    An assessment was made of the Energy Data Base (EDB) of the Department of Energy's Technical Information Center (TIC). As the major resource containing access information to the world's energy literature, EDB products and services are used extensively by energy researchers to identify journal articles, technical reports and other items of potential utility in their work. The approach taken to assessing value begins with the measurement of extent of use of the EDB. Apparent value is measured in terms of willingness to pay. Consequential value is measured in terms of effect - for searching, the cost of reading which results; and for reading, the savings which result from the application of the information obtained in reading. Resulting estimates of value reflect value to the searchers, the reader, and the reader's organization or funding source. A survey of the 60,000 scientists and eingineers funded by the DOE shows that annually they read about 7.1 million journal articles and 6.6 million technical reports. A wide range of savings values were reported for one-fourth of all article readings and three-fourths of all report readings. There was an average savings of $590 per reading of all articles; there was an average savings of $1280 for technical reports. The total annual savings attributable to reading by DOE-funded scientists and engineers is estimated to be about $13 billion. An investment of $5.3 billion in the generation of information and about $500 million in processing and using information yields a partial return of about $13 billion. Overall, this partial return on investment is about 2.2 to 1. In determining the value of EDB only those searches and readings directly attributable to it are included in the analysis. The values are $20 million to the searchers, $117 million to the readers and $3.6 billion to DOE.

  3. Image-based non-contact monitoring of skin texture changed by piloerection for emotion estimation

    Science.gov (United States)

    Uchida, Mihiro; Akaho, Rina; Ogawa, Keiko; Tsumura, Norimichi

    2018-02-01

    In this paper, we find the effective feature values of skin textures captured by non-contact camera to monitor piloerection on the skin for emotion estimation. Recently, emotion estimation is required for service robots to interact with human more naturally. There are a lot of researches of estimating emotion and additional methods are required to improve emotion estimation because using only a few methods may not give enough information for emotion estimation. In the previous study, it is necessary to fix a device on the subject's arm for detecting piloerection, but the contact monitoring can be stress itself and distract the subject from concentrating in the stimuli and evoking strong emotion. So, we focused on the piloerection as the object obtained with non-contact methods. The piloerection is observed as goose bumps on the skin when the subject is emotionally moved, scared and so on. This phenomenon is caused by contraction of arrector pili muscles with the activation of sympathetic nervous system. This piloerection changes skin texture. Skin texture is important in the cosmetic industry to evaluate skin condition. Therefore, we thought that it will be effective to evaluate the condition of skin texture for emotion estimation. The evaluations were performed by extracting the effective feature values from skin textures captured with a high resolution camera. The effective feature values should have high correlation with the degree of piloerection. In this paper, we found that standard deviation of short-line inclination angles in the texture is well correlated with the degree of piloerection.

  4. Multicenter Patch Testing With a Resol Resin Based on Phenol and Formaldehyde Within the International Contact Dermatitis Research Group.

    Science.gov (United States)

    Isaksson, Marléne; Ale, Iris; Andersen, Klaus; Diepgen, Thomas; Elsner, Peter; Goossens, An; Goh, Chee-Leok; Jerajani, Hemangi; Maibach, Howard; Matsunaga, Kayoko; McFadden, John; Nixon, Rosemary; Sasseville, Denis; Bruze, Magnus

    2015-01-01

    Contact allergy to phenol-formaldehyde resins (PFRs) based on phenol and formaldehyde is not detected by a p-tertiary-butylphenol-formaldehyde resin included in most baseline patch test series. The aims of this study were to investigate the contact allergy rate to PFR-2 in an international population and to investigate associated simultaneous allergic reactions. Thirteen centers representing the International Contact Dermatitis Research Group included PFR-2 into their patch test baseline series during a period of 6 months in 2012. Of 2259 patients tested, 28 (1.2%) reacted to PFR-2. Of those 28 individuals, one had a positive reaction to formaldehyde and 2 to p-tertiary-butylphenol-formaldehyde resin. Simultaneous allergic reactions were noted to colophonium in 3, to Myroxylon pereirae in 5, and to fragrance mix I in 8. The contact allergy frequency in the tested population (1.2%) merits its inclusion into the international baseline series and possibly also into other baseline series after appropriate investigations. Significantly, overrepresented simultaneous allergic reactions were noted for M. pereirae and fragrance mix I.

  5. Simultaneous Detection of Displacement, Rotation Angle, and Contact Pressure Using Sandpaper Molded Elastomer Based Triple Electrode Sensor.

    Science.gov (United States)

    Choi, Eunsuk; Sul, Onejae; Lee, Seung-Beck

    2017-09-06

    In this article, we report on a flexible sensor based on a sandpaper molded elastomer that simultaneously detects planar displacement, rotation angle, and vertical contact pressure. When displacement, rotation, and contact pressure are applied, the contact area between the translating top elastomer electrode and the stationary three bottom electrodes change characteristically depending on the movement, making it possible to distinguish between them. The sandpaper molded undulating surface of the elastomer reduces friction at the contact allowing the sensor not to affect the movement during measurement. The sensor showed a 0.25 mm −1 displacement sensitivity with a ±33 μm accuracy, a 0.027 degree −1 of rotation sensitivity with ~0.95 degree accuracy, and a 4.96 kP −1 of pressure sensitivity. For possible application to joint movement detection, we demonstrated that our sensor effectively detected the up-and-down motion of a human forefinger and the bending and straightening motion of a human arm.

  6. Energy Data Base corporate author entries

    International Nuclear Information System (INIS)

    Hendricks, P.L.

    1984-04-01

    The US Department of Energy is one of three agencies funding the major portion of government-supported research. One of the ways to locate the results of this research is to find reports in the Energy Data Base (EDB), the comprehensive data base of the Office of Scientific and Technical Information, Technical Information Center, and in publications derived therefrom by referring to the corporate organization performing the research. This information field has been established as an index point retrievable in on-line searching and is included as an index in printed publications. To provide consistent citing of names in bibliographic entries, this authority has been created and maintained as a means of entry of corporate names into the EDB. To locate such information, one can (1) use the seven-digit code number assigned to the corporate entity of interest (enter, for example, IC=9506086) or (2) use one word at a time from the corporate name given (enter, for example, CS=Dominion)

  7. From free energy to expected energy: Improving energy-based value function approximation in reinforcement learning.

    Science.gov (United States)

    Elfwing, Stefan; Uchibe, Eiji; Doya, Kenji

    2016-12-01

    Free-energy based reinforcement learning (FERL) was proposed for learning in high-dimensional state and action spaces. However, the FERL method does only really work well with binary, or close to binary, state input, where the number of active states is fewer than the number of non-active states. In the FERL method, the value function is approximated by the negative free energy of a restricted Boltzmann machine (RBM). In our earlier study, we demonstrated that the performance and the robustness of the FERL method can be improved by scaling the free energy by a constant that is related to the size of network. In this study, we propose that RBM function approximation can be further improved by approximating the value function by the negative expected energy (EERL), instead of the negative free energy, as well as being able to handle continuous state input. We validate our proposed method by demonstrating that EERL: (1) outperforms FERL, as well as standard neural network and linear function approximation, for three versions of a gridworld task with high-dimensional image state input; (2) achieves new state-of-the-art results in stochastic SZ-Tetris in both model-free and model-based learning settings; and (3) significantly outperforms FERL and standard neural network function approximation for a robot navigation task with raw and noisy RGB images as state input and a large number of actions. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  8. CFD simulation of direct contact condensation with ANSYS CFX using surface renewal theory based heat transfer coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Wanninger, Andreas; Ceuca, Sabin Cristian; Macian-Juan, Rafael [Technische Univ. Muenchen, Garching (Germany). Dept. of Nuclear Engineering

    2013-07-01

    Different approaches for the calculation of Direct Contact Condensation (DCC) using Heat Transfer Coefficients (HTC) based on the Surface Renewal Theory (SRT) are tested using the CFD simulation tool ANSYS CFX. The present work constitutes a preliminary study of the flow patterns and conditions observed using different HTC models. A complex 3D flow pattern will be observed in the CFD simulations as well as a strong coupling between the condensation rate and the two-phase flow dynamics. (orig.)

  9. First-principles investigation on the electronic efficiency and binding energy of the contacts formed by graphene and poly-aromatic hydrocarbon anchoring groups

    KAUST Repository

    Li, Yang

    2015-04-28

    © 2015 AIP Publishing LLC. The electronic efficiency and binding energy of contacts formed between graphene electrodes and poly-aromatic hydrocarbon (PAH) anchoring groups have been investigated by the non-equilibrium Green\\'s function formalism combined with density functional theory. Our calculations show that PAH molecules always bind in the interior and at the edge of graphene in the AB stacking manner, and that the binding energy increases following the increase of the number of carbon and hydrogen atoms constituting the PAH molecule. When we move to analyzing the electronic transport properties of molecular junctions with a six-carbon alkyne chain as the central molecule, the electronic efficiency of the graphene-PAH contacts is found to depend on the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the corresponding PAH anchoring group, rather than its size. To be specific, the smaller is the HOMO-LUMO gap of the PAH anchoring group, the higher is the electronic efficiency of the graphene-PAH contact. Although the HOMO-LUMO gap of a PAH molecule depends on its specific configuration, PAH molecules with similar atomic structures show a decreasing trend for their HOMO-LUMO gap as the number of fused benzene rings increases. Therefore, graphene-conjugated molecule-graphene junctions with high-binding and high-conducting graphene-PAH contacts can be realized by choosing appropriate PAH anchor groups with a large area and a small HOMO-LUMO gap.

  10. Ranking multiple docking solutions based on the conservation of inter-residue contacts

    KAUST Repository

    Oliva, Romina M.

    2013-06-17

    Molecular docking is the method of choice for investigating the molecular basis of recognition in a large number of functional protein complexes. However, correctly scoring the obtained docking solutions (decoys) to rank native-like (NL) conformations in the top positions is still an open problem. Herein we present CONSRANK, a simple and effective tool to rank multiple docking solutions, which relies on the conservation of inter-residue contacts in the analyzed decoys ensemble. First it calculates a conservation rate for each inter-residue contact, then it ranks decoys according to their ability to match the more frequently observed contacts. We applied CONSRANK to 102 targets from three different benchmarks, RosettaDock, DOCKGROUND, and Critical Assessment of PRedicted Interactions (CAPRI). The method performs consistently well, both in terms of NL solutions ranked in the top positions and of values of the area under the receiver operating characteristic curve. Its ideal application is to solutions coming from different docking programs and procedures, as in the case of CAPRI targets. For all the analyzed CAPRI targets where a comparison is feasible, CONSRANK outperforms the CAPRI scorers. The fraction of NL solutions in the top ten positions in the RosettaDock, DOCKGROUND, and CAPRI benchmarks is enriched on average by a factor of 3.0, 1.9, and 9.9, respectively. Interestingly, CONSRANK is also able to specifically single out the high/medium quality (HMQ) solutions from the docking decoys ensemble: it ranks 46.2 and 70.8% of the total HMQ solutions available for the RosettaDock and CAPRI targets, respectively, within the top 20 positions. © 2013 Wiley Periodicals, Inc.

  11. Parylene-based active micro space radiator with thermal contact switch

    Science.gov (United States)

    Ueno, Ai; Suzuki, Yuji

    2014-03-01

    Thermal management is crucial for highly functional spacecrafts exposed to large fluctuations of internal heat dissipation and/or thermal boundary conditions. Since thermal radiation is the only means for heat removal, effective control of radiation is required for advanced space missions. In the present study, a MEMS (Micro Electro Mechanical Systems) active radiator using the contact resistance change has been proposed. Unlike previous bulky thermal louvers/shutters, higher fill factor can be accomplished with an array of electrostatically driven micro diaphragms suspended with polymer tethers. With an early prototype developed with parylene MEMS technologies, radiation heat flux enhancement up to 42% has been achieved.

  12. Development of steel head joints with fiberglass sucker rod on the base of contact stresses investigation

    Energy Technology Data Exchange (ETDEWEB)

    Kopey, B.V.; Kopey, L.B. [Ivano-Frankivsk State Technical Oil and Gas University (Ukraine); Maksymuk, A.V.; Shcherbyna, N.M. [National Ukrainian Academy of Sciences (Ukraine)

    1998-12-31

    The methods of calculation of contact stresses during cylinder shell tube - steel bandage interaction are presented. Tymoshenko`s generalized theory of shells serves as a basis for investigating steel head to fiberglass sucker rod joint strength. This theory allows to consider mechanical performance of composite materials. The problem is reduced to solving Fredholm integral equation of second degree. The numeric analysis is performed. Several joints of composite body with steel head are proposed. The full-size sucker rod fatigue tests are performed to determine the fatigue limit under the bending and axial cyclic loads in the medium of oil well fluids. (orig.)

  13. Chemical structure of vanadium-based contact formation on n-AlN

    Energy Technology Data Exchange (ETDEWEB)

    Pookpanratana, S.; France, R.; Blum, M.; Bell, A.; Bar, M.; Weinhardt, L.; Zhang, Y.; Hofmann, T.; Fuchs, O.; Yang, W.; Denlinger, J. D.; Mulcahy, S.; Moustakas, T. D.; Heske, Clemens

    2010-05-17

    We have investigated the chemical interaction between a Au/V/Al/V layer structure and n-type AlN epilayers using soft x-ray photoemission, x-ray emission spectroscopy, and atomic force microscopy. To understand the complex processes involved in this multicomponent system, we have studied the interface before and after a rapid thermal annealing step. We find the formation of a number of chemical phases at the interface, including VN, metallic vanadium, aluminum oxide, and metallic gold. An interaction mechanism for metal contact formation on the entire n-(Al,Ga)N system is proposed.

  14. The use of high energy laser-plasma sources in soft X-ray contact microscopy of living biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Batani, D.; Botto, C.; Moret, M.; Milani, M.; Lucchini, G. [Universita degli Studi di Milano-Bicocca and INFM, Milano (Italy); Eidmann, K. [Max-Planck-Institut fuer Quantenoptik, Garching (Germany); Cotelli, F.; Lora Lamia Donin, C.; Poletti, G. [Universita di Milano (Italy); Ford, T.; Stead, A. [London Univ., Royal Holloway (United Kingdom)

    2002-11-01

    In this paper the results of an experiment on soft X-ray contact microscopy using a laser-plasma source are presented. A resolution of 50 nm has been achieved imaging pig sperm cells, while other specimens, such as algae and yeast cells, showed internal details, proving the technique to be a powerful tool for biological investigations. Original biological information has been obtained and the conditions for optimal image formation have been studied. (authors)

  15. Estimation of interaction energy and contact stiffness in atomic-scale sliding on a model sodium chloride surface in ethanol.

    Science.gov (United States)

    Agmon, Liron; Shahar, Itai; Yosufov, Danny; Pimentel, Carlos; Pina, Carlos M; Gnecco, Enrico; Berkovich, Ronen

    2018-03-16

    Friction force microscopy (FFM) in aqueous environments has recently proven to be a very effective method for lattice-resolution imaging of crystal surfaces. Here we demonstrate the use of ethanol for similar measurements on water-soluble materials. Lattice resolved frictional stick-slip traces of a cleaved NaCl(100) surface submerged in ethanol are compared with previous obtained FFM results in ultrahigh vacuum (UHV). We use the Prandtl-Tomlinson framework to estimate the amplitude of the corrugation potential and the contact stiffness. The surface potential amplitude scales with the applied normal loads are in good agreement with data obtained for NaCl measured under UHV conditions, but demonstrates deviations from the ideal periodic potential given by the Prandtl-Tomlinson model. An additional finding is that the use of ethanol allows us to explore higher load ranges without detectable evidence of surface wear. The contact stiffness does not vary significantly with the normal load up to 38 nN, while above it a sudden increase by almost one order of magnitude was observed. Comparing this to previous results suggests that considerable atom rearrangements may occur in the contact region, although the (100) surface structure is preserved by ethanol-assisted diffusion of Na and Cl ions.

  16. Algal-Based Renewable Energy for Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Fritsen, Christian [Desert Research Institute, Las Vegas, NV (United States)

    2017-03-31

    To help in the overall evaluation of the potential for growing algal biomass in high productivity systems, we conducted a study that evaluated water from geothermal sources and cultivated mixed consortia from hot springs in Nevada, we evaluated their growth at moderately high varying temperatures and then evaluated potential manipulations that could possibly increase their biomass and oleaginous production. Studies were conducted at scales ranging from the laboratory benchtop to raceways in field settings. Mixed consortia were readily grown at all scales and growth could be maintained in Nevada year round. Moderate productivities were attained even during the shoulder seasons- where temperature control was maintained by hot water and seasonally cold temperatures when there was still plentiful solar radiation. The results enhance the prospects for economic feasibility of developing algal based industries in areas with geothermal energy or even other large alternative sources of heat that are not being used for other purposes. The public may benefit from such development as a means for economic development as well as development of industries for alternative energy and products that do not rely on fossil fuels.

  17. Dielectric Sensors Based on Electromagnetic Energy Tunneling

    Directory of Open Access Journals (Sweden)

    Omar Siddiqui

    2015-03-01

    Full Text Available We show that metallic wires embedded in narrow waveguide bends and channels demonstrate resonance behavior at specific frequencies. The electromagnetic energy at these resonances tunnels through the narrow waveguide channels with almost no propagation losses. Under the tunneling behavior, high-intensity electromagnetic fields are produced in the vicinity of the metallic wires. These intense field resonances can be exploited to build highly sensitive dielectric sensors. The sensor operation is explained with the help of full-wave simulations. A practical setup consisting of a 3D waveguide bend is presented to experimentally observe the tunneling phenomenon. The tunneling frequency is predicted by determining the input impedance minima through a variational formula based on the Green function of a probe-excited parallel plate waveguide.

  18. Fully-Non-Contact Masking-Based Holography Inspection on Dimensionally Responsive Artwork Materials

    Directory of Open Access Journals (Sweden)

    Vivi Tornari

    2008-12-01

    Full Text Available Environmental control in galleries and museums is a necessity and is informed by the knowledge of ongoing processes of deterioration which can threaten the integrity and stability of artworks. Invisible dimensional changes in many works of art occur following environmental fluctuations as materials respond to the changes in humidity and temperature. The constant influence of dimensional changes usually remains invisible until displacement generates visible deterioration and irreversible damage. This paper exploits fully non contact coherent interferometry in a sequential masking procedure for visualising and studying surface deformation which is the direct effect of dimensional alterations induced by humidity changes. Surface deformation during dimensional displacements of constituent materials may occur on any artwork within an unstable environment. In this context, the presented research study explores the diagnostic potential of fully non contact sensors for the direct structural assessment of environmental effects as they occur in real time on works of art. The method is employed to characterise material responses, complementing and improving understanding of material behaviour in unstable environments.

  19. Performance optimization of MOS-like carbon nanotube-FETs with realistic source/drain contacts based on electrostatic doping

    International Nuclear Information System (INIS)

    Zhou Hailiang; Zhang Minxuan; Hao Yue

    2010-01-01

    Due to carrier band-to-band-tunneling (BTBT) through channel-source/drain contacts, conventional MOS-like Carbon Nanotube Field Effect Transistors (C-CNFETs) suffer from ambipolar conductance, which deteriorates the device performance greatly. In order to reduce such ambipolar behavior, a novel device structure based on electrostatic doping is proposed and all kinds of source/drain contacting conditions are considered in this paper. The non-equilibrium Green's function (NEGF) formalism based simulation results show that, with proper choice of tuning voltage, such electrostatic doping strategy can not only reduce the ambipolar conductance but also improve the sub-threshold performance, even with source/drain contacts being of Schottky type. And these are both quite desirable in circuit design to reduce the system power and improve the frequency as well. Further study reveals that the performance of the proposed design depends strongly on the choice of tuning voltage value, which should be paid much attention to obtain a proper trade-off between power and speed in application. (semiconductor devices)

  20. Investigating interfacial contact configuration and behavior of single-walled carbon nanotube-based nanodevice with atomistic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Jianlei, E-mail: cjlxjtu@mail.xjtu.edu.cn; Zhang, Jianwei [Xi’an Jiaotong University, State Key Laboratory for Manufacturing Systems Engineering (China); He, Xiaoqiao, E-mail: bcxqhe@cityu.edu.hk [City University of Hong Kong, Department of Architecture and Civil Engineering (Hong Kong); Mei, Xuesong; Wang, Wenjun [Xi’an Jiaotong University, State Key Laboratory for Manufacturing Systems Engineering (China); Yang, Xinju [Fudan University, State Key Laboratory of Surface Physics and Department of Physics (China); Xie, Hui; Yang, Lijun; Wang, Yang [Harbin Institute of Technology, State Key Laboratory of Robotics and Systems (China)

    2017-03-15

    Carbon nanotubes (CNTs), including single-walled carbon nanotubes (SWNTs) and multi-walled carbon nanotubes (MWNTs), are considered to be the promising candidates for next-generation interconnects with excellent physical and chemical properties ranging from ultrahigh mechanical strength, to electrical properties, to thermal conductivity, to optical properties, etc. To further study the interfacial contact configurations of SWNT-based nanodevice with a 13.56-Å diameter, the corresponding simulations are carried out with the molecular dynamic method. The nanotube collapses dramatically into the surface with the complete collapse on the Au/Ag/graphite electrode surface and slight distortion on the Si/SiO{sub 2} substrate surface, respectively. The related dominant mechanism is studied and explained. Meanwhile, the interfacial contact configuration and behavior, depended on other factors, are also analyzed in this article.

  1. Ultraviolet/violet dual-color electroluminescence based on n-ZnO single crystal/p-GaN direct-contact light-emitting diode

    International Nuclear Information System (INIS)

    Li, Songzhan; Lin, Wenwen; Fang, Guojia; Huang, Feng; Huang, Huihui; Long, Hao; Mo, Xiaoming; Wang, Haoning; Guan, Wenjie; Zhao, Xingzhong

    2013-01-01

    We have fabricated a fully transparent ultraviolet (UV)/violet dual-color electroluminescence (EL) device based on n-ZnO single crystal and p-GaN via a simple direct-contact method. The device presents dual-color EL under forward and reverse biases—an intense violet emission centered at 400 nm from ZnO and a sharp UV emission peaked at 365 nm from GaN, respectively. The reason for dual color emissions is proposed in terms of the energy band theory and the transmission spectra of ZnO single crystal and p-GaN. -- Highlights: ► A fully transparent LED based on n-ZnO SC and p-GaN is fabricated via the direct-contact method. ► The n-ZnO SC/p-GaN device shows UV/violet dual-color emission under electrically pumped. ► The device presents a violet emission 400 nm and a UV emission 365 nm under forward and reverse biases. ► The EL of the dual-color device displays good stability and reproducibility

  2. Study of degradation processes kinetics in ohmic contacts of resonant tunneling diodes based on nanoscale AlAs/GaAs heterostructures under influence of temperature

    Science.gov (United States)

    Makeev, M. O.; Meshkov, S. A.

    2017-07-01

    The artificial aging of resonant tunneling diodes based on nanoscale AlAs/GaAs heterostructures was conducted. As a result of the thermal influence resonant tunneling diodes IV curves degrade firstly due to ohmic contacts' degradation. To assess AlAs/GaAs resonant tunneling diodes degradation level and to predict their reliability, a functional dependence of the contact resistance of resonant tunneling diode AuGeNi ohmic contacts on time and temperature was offered.

  3. Stress Regression Analysis of Asphalt Concrete Deck Pavement Based on Orthogonal Experimental Design and Interlayer Contact

    Science.gov (United States)

    Wang, Xuntao; Feng, Jianhu; Wang, Hu; Hong, Shidi; Zheng, Supei

    2018-03-01

    A three-dimensional finite element box girder bridge and its asphalt concrete deck pavement were established by ANSYS software, and the interlayer bonding condition of asphalt concrete deck pavement was assumed to be contact bonding condition. Orthogonal experimental design is used to arrange the testing plans of material parameters, and an evaluation of the effect of different material parameters in the mechanical response of asphalt concrete surface layer was conducted by multiple linear regression model and using the results from the finite element analysis. Results indicated that stress regression equations can well predict the stress of the asphalt concrete surface layer, and elastic modulus of waterproof layer has a significant influence on stress values of asphalt concrete surface layer.

  4. Multi-Valued Logic Gates based on Ballistic Transport in Quantum Point Contacts

    Science.gov (United States)

    Seo, M.; Hong, C.; Lee, S.-Y.; Choi, H. K.; Kim, N.; Chung, Y.; Umansky, V.; Mahalu, D.

    2014-01-01

    Multi-valued logic gates, which can handle quaternary numbers as inputs, are developed by exploiting the ballistic transport properties of quantum point contacts in series. The principle of a logic gate that finds the minimum of two quaternary number inputs is demonstrated. The device is scalable to allow multiple inputs, which makes it possible to find the minimum of multiple inputs in a single gate operation. Also, the principle of a half-adder for quaternary number inputs is demonstrated. First, an adder that adds up two quaternary numbers and outputs the sum of inputs is demonstrated. Second, a device to express the sum of the adder into two quaternary digits [Carry (first digit) and Sum (second digit)] is demonstrated. All the logic gates presented in this paper can in principle be extended to allow decimal number inputs with high quality QPCs.

  5. Superconducting energy gap distribution in c-axis oriented MgB sub 2 thin film from point contact study

    CERN Document Server

    Naidyuk, Yu G; Tyutrina, L V; Bobrov, N L; Chubov, P N; Kang, W N; Hyeong Jin Kim; Eun Mi Choi; Sung Ik Lee

    2002-01-01

    The voltage dependent differential resistance dV/dI(V) curves of metallic point contacts between MgB sub 2 thin film and Ag, which exhibit clear Andreev reflection connected with the superconducting gap are analyzed. About one half of the curves show the presence of a second larger gap. The histogram of the double gap distribution reveals distinct maxima at 2.4 and 7 MeV. The double gap distribution is in qualitative agreement with the distribution of gap values over the Fermi surface calculated previously. These observations prove a widely discussed multi-gap scenario for MgB sub 2

  6. Energy-based and biomimetic robotics

    NARCIS (Netherlands)

    Folkertsma, Gerrit Adriaan

    2017-01-01

    All physical systems interact by exchanging power, or energy. This energy can be explicitly taken into account when designing robotic systems, in dynamic models of systems and controllers, leading to more insight in energy-related effects. In this thesis, a biomimetic cheetah robot is developed, by

  7. Recruiting former melanoma patients via hospitals in comparison to office-based dermatologists in a register-based cohort study that required indirect contact

    Directory of Open Access Journals (Sweden)

    S. R. Zeissig

    2017-11-01

    Full Text Available Abstract Background There are detailed reviews about different recruitment strategies, but not with regard to differences between recruitment of hospital-based versus office-based physicians. Within this study, the two different recruitment schemes are compared. Advantages and disadvantages of different ways of recruitment in registry-based studies are discussed. Methods In a cross-sectional cancer-registry-based study, long-term melanoma patients were contacted by dermatologists rather than directly by the registry on the basis of the legal situation. Logistic regression models and generalized estimating equations were used to assess effects of various patient and physician characteristics on participation and data quality. Especially differences between hospital-based versus office-based dermatologists are evaluated. Results Seventy two out of 112 contacted dermatologists took part in the study (64.3%. The cooperation proportion was 52.2% (689 participants/1320 contacted patients. Participants and non-participants differed regarding age and sex, but not regarding other social demographic factors and cancer stage. We did not observe a difference in patient participation between hospital-based versus office-based dermatologists (OR 1.08 [CI 0.84–1.39]; p = 0.57. However, medical data provided by the cancer registry were better for participants registered and recruited by hospitals. Conclusions In cohort studies with epidemiological cancer registries, recruitment via physicians has potential disadvantages and is more complex. If this indirect way of contact is mandatory, we recommend recruitment procedures including hospital-based rather than office-based physicians. However, physician characteristics were not associated with outcome.

  8. Identification of risk products for fragrance contact allergy: a case-referent study based on patients' histories.

    Science.gov (United States)

    Johansen, J D; Andersen, T F; Kjøller, M; Veien, N; Avnstorp, C; Andersen, K E; Menné, T

    1998-06-01

    Fragrances are the first or second most common cause of contact allergy in dermatitis patients. The aim of this study was to identify risk products for fragrance contact allergy. The design was a case-control study with a case group of 78 fragrance-mix-positive eczema patients and two control groups, one consisting of 1,279 subjects selected as a random sample of the general population and the other consisting of 806 fragrance-mix-negative eczema patients. The identification of risk products was based on the patients' histories of rash to scented products. Analysis of the associations between first-time rash caused by different specified product categories and fragrance mix sensitivity was performed using logistic regression. It was found that first-time rash caused by deodorant sprays and/or perfumes were related to fragrance contact allergy in a comparison with both control groups. The risk (odds ratio) of being diagnosed as fragrance allergic was 2.3 to 2.9 greater in cases of a history of first-time rash to deodorant sprays and 3.3 to 3.4 greater in cases of a history of rash to perfumes than if no such history were present. First-time rash to cleansing agents, deodorant sticks, or hand lotions was also statistically significant but only in comparison with one of the control groups. Safety evaluation of fragrance materials used in perfumes and deodorant sprays should be performed with special attention.

  9. Electrical transport properties of black phosphorus based field-effect transistor with Au/Co/MgO tunneling contacts

    Science.gov (United States)

    Liang, Shiheng; Yang, Huaiwen; Djeffal, Abdelhak; Tao, Bingshan; Mc-Murtry, Stefan; Mangin, Stéphane; Lu, Yuan

    2017-10-01

    Black phosphorus (BP) has recently emerged as a promising two-dimensional direct bandgap semiconducting material. Here, we report the fabrication and the electrical transport measurements of the black phosphorus based field-effect transistor with the Au/Co/MgO as drain and source tunneling contacts. By modulating the back-gate voltage, the multilayer black phosphorus channel exhibits ambipolar characteristics (both n-type and p-type) and the conduction behavior can be switched from hole dominated to electron dominated transport region. In the hole dominated region, we have measured a minimum of Schottky barrier height of 37 meV for Au/Co/MgO contact on BP. Moreover, the transistor ON/OFF (Ion/Ioff) ratio is obtained as large as 107 at 20 K and 105 at 300 K. A systematic study of the temperature and the back-gate voltage dependent conduction properties has been performed to understand the modulation of band structure and the ambipolar behavior. The demonstration of high ON/OFF ratio and low Schottky barrier height by using Au/Co/MgO tunneling contacts reveals a promising potential for spintronics applications with multilayer black phosphorus field-effect transistor.

  10. Sensing with Superconducting Point Contacts

    Directory of Open Access Journals (Sweden)

    Argo Nurbawono

    2012-05-01

    Full Text Available Superconducting point contacts have been used for measuring magnetic polarizations, identifying magnetic impurities, electronic structures, and even the vibrational modes of small molecules. Due to intrinsically small energy scale in the subgap structures of the supercurrent determined by the size of the superconducting energy gap, superconductors provide ultrahigh sensitivities for high resolution spectroscopies. The so-called Andreev reflection process between normal metal and superconductor carries complex and rich information which can be utilized as powerful sensor when fully exploited. In this review, we would discuss recent experimental and theoretical developments in the supercurrent transport through superconducting point contacts and their relevance to sensing applications, and we would highlight their current issues and potentials. A true utilization of the method based on Andreev reflection analysis opens up possibilities for a new class of ultrasensitive sensors.

  11. Innovation: Contact

    African Journals Online (AJOL)

    Principal Contact. Ruth Hoskins Editor University of KwaZulu-Natal, Information Studies Programme Email: hoskinsr@ukzn.ac.za. Support Contact. Gita Ramdass Email: ramdass@ukzn.ac.za. ISSN: 1025-8892. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More ...

  12. A parallel finite element procedure for contact-impact problems using edge-based smooth triangular element and GPU

    Science.gov (United States)

    Cai, Yong; Cui, Xiangyang; Li, Guangyao; Liu, Wenyang

    2018-04-01

    The edge-smooth finite element method (ES-FEM) can improve the computational accuracy of triangular shell elements and the mesh partition efficiency of complex models. In this paper, an approach is developed to perform explicit finite element simulations of contact-impact problems with a graphical processing unit (GPU) using a special edge-smooth triangular shell element based on ES-FEM. Of critical importance for this problem is achieving finer-grained parallelism to enable efficient data loading and to minimize communication between the device and host. Four kinds of parallel strategies are then developed to efficiently solve these ES-FEM based shell element formulas, and various optimization methods are adopted to ensure aligned memory access. Special focus is dedicated to developing an approach for the parallel construction of edge systems. A parallel hierarchy-territory contact-searching algorithm (HITA) and a parallel penalty function calculation method are embedded in this parallel explicit algorithm. Finally, the program flow is well designed, and a GPU-based simulation system is developed, using Nvidia's CUDA. Several numerical examples are presented to illustrate the high quality of the results obtained with the proposed methods. In addition, the GPU-based parallel computation is shown to significantly reduce the computing time.

  13. Development of ZnO:Al-based transparent contacts deposited at low-temperature by RF-sputtering on InN layers

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, S. [Departamento de Energias Renovables, Energia Solar Fotovoltaica, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Avda. Complutense 22, 28040 Madrid (Spain); Naranjo, F.B.; Valdueza-Felip, S. [Grupo de Ingenieria Fotonica, Departamento de Electronica, Escuela Politecnica Superior, Universidad de Alcala Campus Universitario, 28871 Alcala de Henares, Madrid (Spain); Abril, O. de [ISOM and Departamento de Fisica Aplicada, Escuela Tecnica Superior de Ingenieros de Telecomunicacion, Universidad Politenica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2012-03-15

    Nitride semiconductors (Al,Ga,In)N attain material properties that make them suitable for photovoltaic and optoelectronics devices to be used in hard environments. These properties include an energy gap continuously tuneable within the energy range of the solar spectrum, a high radiation resistance and thermal stability. The developing of efficient devices requires contacts with low resistivity and high transmittance in visible region. ZnO:Al (AZO) emerges as a feasible candidate for transparent contact to nitride semiconductors, taking advantage of its low resistivity, high transparency in visible wavelengths and a very low lattice mismatch with respect to nitride semiconductors. This work presents a study of the applications of AZO films deposited at low-temperature by RF magnetron sputtering as transparent contact for InN layers. The optimization of AZO conditions deposition lead to the obtaining of contacts which shows an ohmic behaviour for the as-deposited layer, regardless the thickness of the ZnO:Al contact layer. Specific contact resistances of 1.6 {omega}.cm{sup 2} were achieved for the contact with 90 nm thick ZnO:Al layer without any post-deposition treatment (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Research on vibration characteristics of gun barrel based on contact model

    Science.gov (United States)

    Zhao, Yang; Zhou, Qizheng; Yue, Pengfei

    2017-04-01

    In order to study vibration characteristics of the gun barrel under the action of moving projectile, the gun barrel is simplified to cross sectional cantilever beam such as Euler. Considering contact conditions of inertia effect and projectile with the gun barrel, the equation of lateral vibration of the gun barrel is established under the projectile-gun coupling effect; the modal analysis method is used to give the analytic solutions of equation series. The effect of the motion parameters the projectile on the vibration of gun barrel is discussed, and characteristics of vibration of gun barrel are further studied under two conditions of repeating and projectile with mass eccentricity. The research results show that reasonable control of the acceleration of the projectile in the gun bore, and reduction of projectile mass eccentricity can help reduce the muzzle vibration at the gun firing. The research results can provide reference for overall design of the gun, and the modeling and analysis method used in the paper can be promoted for the solution of vibration of other related projects under the moving excitation.

  15. Contact-based model for strategy updating and evolution of cooperation

    Science.gov (United States)

    Zhang, Jianlei; Chen, Zengqiang

    2016-06-01

    To establish an available model for the astoundingly strategy decision process of players is not easy, sparking heated debate about the related strategy updating rules is intriguing. Models for evolutionary games have traditionally assumed that players imitate their successful partners by the comparison of respective payoffs, raising the question of what happens if the game information is not easily available. Focusing on this yet-unsolved case, the motivation behind the work presented here is to establish a novel model for the updating of states in a spatial population, by detouring the required payoffs in previous models and considering much more players' contact patterns. It can be handy and understandable to employ switching probabilities for determining the microscopic dynamics of strategy evolution. Our results illuminate the conditions under which the steady coexistence of competing strategies is possible. These findings reveal that the evolutionary fate of the coexisting strategies can be calculated analytically, and provide novel hints for the resolution of cooperative dilemmas in a competitive context. We hope that our results have disclosed new explanations about the survival and coexistence of competing strategies in structured populations.

  16. Exploring New Mechanisms for Effective Antimicrobial Materials: Electric Contact-Killing Based on Multiple Schottky Barriers.

    Science.gov (United States)

    de Lucas-Gil, Eva; Reinosa, Julián J; Neuhaus, Kerstin; Vera-Londono, Liliana; Martín-González, Marisol; Fernández, José F; Rubio-Marcos, Fernando

    2017-08-09

    The increasing threat of multidrug-resistance organisms is a cause for worldwide concern. Progressively microorganisms become resistant to commonly used antibiotics, which are a healthcare challenge. Thus, the discovery of new antimicrobial agents or new mechanisms different from those used is necessary. Here, we report an effective and selective antimicrobial activity of microstructured ZnO (Ms-ZnO) agent through the design of a novel star-shaped morphology, resulting in modulation of surface charge orientation. Specifically, we find that Ms-ZnO particles are composed of platelet stacked structure, which generates multiple Schottky barriers due to the misalignment of crystallographic orientations. We also demonstrated that this effect allows negative charge accumulation in localized regions of the structure to act as "charged domain walls", thereby improving the antimicrobial effectiveness by electric discharging effect. We use a combination of field emission scanning electron microscopy (FE-SEM), SEM-cathodoluminescence imaging, and Kelvin probe force microscopy (KPFM) to determine that the antimicrobial activity is a result of microbial membrane physical damage caused by direct contact with the Ms-ZnO agent. It is important to point out that Ms-ZnO does not use the photocatalysis or the Zn 2+ released as the main antimicrobial mechanism, so consequently this material would show low toxicity and robust stability. This approach opens new possibilities to understand both the physical interactions role as main antimicrobial mechanisms and insight into the coupled role of hierarchical morphologies and surface functionality on the antimicrobial activity.

  17. Potential contact and intraocular lenses based on hydrophilic/hydrophobic sulfonated syndiotactic polystyrene membranes

    Directory of Open Access Journals (Sweden)

    Simona Zuppolini

    2017-10-01

    Full Text Available Crystalline films of syndiotactic polystyrene (s-PS, a commercially available thermoplastic polymer, having a highly hydrophilic amorphous phase, were achieved by using a mild solid-state sulfonation procedure. Despite the used mild process conditions, an easy and uniform sulfonation of the phenyl rings of the amorphous phase is obtained. The crystallinity of the polymer was not affect by the sulfonation degree (S, at least at S less than 20%, and the obtained polymer films show the nanoporous crystalline form of s-PS. As widely reported in literature, the nanoporous nature of the polymer crystalline phase gives to these materials the ability to absorb and release organic molecules of appropriate size and polarity. This property, coupled to transparency, makes these materials potentially useful intraocular lens (IOLs and contact lens applications. Sulfonation procedure and sulfonated film samples characterization by using wide-angle X-ray diffraction (WAXD, Fourier-transform infrared (FTIR and ultraviolet-visible (UV-vis spectroscopy techniques and water sorption tests were reported. Furthermore, the biocompatibility study demonstrated no cytotoxicity and appropriate cell interaction properties for the specific applications.

  18. A physics-based model of gate-tunable metal–graphene contact resistance benchmarked against experimental data

    International Nuclear Information System (INIS)

    Chaves, Ferney A; Jiménez, David; Sagade, Abhay A; Neumaier, Daniel; Kim, Wonjae; Riikonen, Juha; Lipsanen, Harri

    2015-01-01

    Metal–graphene contact resistance is a technological bottleneck in the realization of viable graphene-based electronics. We report a model that is useful for finding the gate-tunable components of this resistance, determined by the tunneling of carriers between the 3D metal and 2D graphene underneath, followed by Klein tunneling to the graphene in the channel. This model quantifies the intrinsic factors that control that resistance, including the effect of unintended chemical doping. Our results agree with experimental results for several metals. (paper)

  19. Friction Compensation in Energy-Based Bilateral Telemanipulation

    NARCIS (Netherlands)

    Franken, M.C.J.; Misra, Sarthak; Stramigioli, Stefano

    2010-01-01

    In bilateral telemanipulation algorithms based on time-domain passivity, internal friction in the devices poses an additional energy drain. Based on a model of the friction, the dissipated energy can be estimated and reclaimed inside the energy balance of the control algorithm. As long as the

  20. Analysis of the influence of foundation beams on displacements and bearing capacity of horizontally loaded supports of power lines and contact systems basing on theoretical and experimental data

    Directory of Open Access Journals (Sweden)

    Buslov Anatoliy Semenovich

    2016-10-01

    Full Text Available The issues of bearing structures reliability for energy lines are of special importance in case of the use of single post horizontally loaded pile foundations of power lines and contact system supports. The required level of operational reliability of single post horizontally loaded supports in case of variability of strain-strength features of foundation soils along the route may be provided by using optimal sizes and number of foundation beams creating additional reactive impedance of soil to the loaded support. Foundation beams laid in soil perpendicular to a horizontally loaded support for increasing its bearing capacity are rather widely used. Though the issues of technical and economic substantiation of the choice of optimal sizes and number of beams influencing the strain and bearing capacity of power lines and contact system supports haven’t been studied enough. Basing on the experimental and theoretical studies the authors proposes his assessment of technical and economical efficiency of the use of foundation beams depending on their geometrical parameters, the amount and height of horizontal loading on a support.

  1. Department of Energy Review of Laboratory Programs for Women Points-of-Contact Committee: Comparative Report, June 1995

    Energy Technology Data Exchange (ETDEWEB)

    McLane, V.; Layne, A.

    1995-06-01

    A survey of the DOE facilities was undertaken by the Points-of-Contact for the DOE Review of Laboratory Programs for Women in order to gather data to be used as a baseline against which to measure future progress. We plan to look at current programs already in place and evaluate them with a view to deciding which programs are most effective, and selecting model programs suitable for implementation at other facilities. The survey focused on four areas: 1) statistical data, 2) laboratory policy, 3) formal and informal programs which affect the quality of life in the work environment, and career development and advancement, and 4) educational programs. Although this report focuses on women, the problems discussed affect all DOE facility employees.

  2. A study of effects of electrode contacts on performance of organic-based light-emitting field-effect transistors

    Science.gov (United States)

    Kim, Dae-Kyu; Choi, Jong-Ho

    2018-02-01

    Herein is presented a comparative performance analysis of heterojunction organic-based light-emitting field-effect transistors (OLEFETs) with symmetric (Au only) and asymmetric (Au and LiF/Al) electrode contacts. The devices had a top source-drain contact with long-channel geometry and were produced by sequentially depositing p-type pentacene and n-type N,N‧-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (P13) using a neutral cluster beam deposition apparatus. The spectroscopic, structural and morphological properties of the organic thin films were examined using photoluminescence (PL) spectroscopy, X-ray diffraction (XRD) method, laser scanning confocal and atomic force microscopy (LSCM, AFM). Based upon the growth of high-quality, well-packed crystalline thin films, the devices demonstrated ambipolar field-effect characteristics, stress-free operational stability, and light emission under ambient conditions. Various device parameters were derived from the fits of the observed characteristics. The hole mobilities were nearly equal irrespective of the electrode contacts, whereas the electron mobilities of the transistors with LiF/Al drain electrodes were higher due to the low injection barrier. For the OLEFETs with symmetric electrodes, electroluminescence (EL) occurred only in the vicinity of the hole-injecting electrode, whereas for the OLEFETs with asymmetric electrodes, the emission occurred in the vicinity of both hole- and electron-injecting electrodes. By tuning the carrier injection and transport through high- and low-work function metals, the hole-electron recombination sites could be controlled. The operating conduction and light emission mechanism are discussed with the aid of EL images obtained using a charge-coupled device (CCD) camera.

  3. First Contact: interprofessional education based on medical students' experiences from their nursing internship

    Directory of Open Access Journals (Sweden)

    Eich-Krohm, Astrid

    2016-04-01

    Full Text Available Goal: The aim of the course “interprofessional communication and nursing” is to reflect medical students’ experiences from the nursing internship. The content of the course focuses on barriers and support of interprofessional communication as a foundation for teamwork between nursing professionals and physicians. The nursing internship is for most medical students the first contact with nursing professionals and can lead to perceptions about the other group that might hinder interprofessional teamwork and consequently harm patients. To meet the demographic challenges ahead it is important to emphasize interprofessional education in the study of medicine and better prepare future physicians for interprofessional collaboration. Method: The design of the course includes an assessment of a change in the students’ perceptions about nursing and interprofessional communication. The first class meeting presents the starting point of the assessment and visualizes students’ perceptions of nursing and medicine. The content of the following class meetings serve to enhance the students’ knowledge about nursing as a profession with its own theories, science and scholarship. In addition, all students have to write a research paper that entails to interview one nursing professional and one physician about their ideas of interprofessional communication and to compare the interviews with their own experiences from the nursing internship. To access what students learned during the course a reflective discussion takes place at the last meeting combined with an analysis of the students’ research papers. Results: The assessment of the students’ perceptions about the nursing profession and the importance of successful interprofessional communication showed a new and deeper understanding of the topic. They were able to identify barriers and support measures of interprofessional communication and their own responsibilities as part of a team

  4. First Contact: interprofessional education based on medical students' experiences from their nursing internship.

    Science.gov (United States)

    Eich-Krohm, Astrid; Kaufmann, Alexandra; Winkler-Stuck, Kirstin; Werwick, Katrin; Spura, Anke; Robra, Bernt-Peter

    2016-01-01

    The aim of the course "interprofessional communication and nursing" is to reflect medical students' experiences from the nursing internship. The content of the course focuses on barriers and support of interprofessional communication as a foundation for teamwork between nursing professionals and physicians. The nursing internship is for most medical students the first contact with nursing professionals and can lead to perceptions about the other group that might hinder interprofessional teamwork and consequently harm patients. To meet the demographic challenges ahead it is important to emphasize interprofessional education in the study of medicine and better prepare future physicians for interprofessional collaboration. The design of the course includes an assessment of a change in the students' perceptions about nursing and interprofessional communication. The first class meeting presents the starting point of the assessment and visualizes students' perceptions of nursing and medicine. The content of the following class meetings serve to enhance the students' knowledge about nursing as a profession with its own theories, science and scholarship. In addition, all students have to write a research paper that entails to interview one nursing professional and one physician about their ideas of interprofessional communication and to compare the interviews with their own experiences from the nursing internship. To access what students learned during the course a reflective discussion takes place at the last meeting combined with an analysis of the students' research papers. The assessment of the students' perceptions about the nursing profession and the importance of successful interprofessional communication showed a new and deeper understanding of the topic. They were able to identify barriers and support measures of interprofessional communication and their own responsibilities as part of a team. Interprofessional education is an important part of medical education

  5. Demonstrating sustainable energy: A review-based model of sustainable energy demonstration projects

    NARCIS (Netherlands)

    Bossink, Bart

    2017-01-01

    This article develops a model of sustainable energy demonstration projects, based on a review of 229 scientific publications on demonstrations in renewable and sustainable energy. The model addresses the basic organizational characteristics (aim, cooperative form, and physical location) and learning

  6. Flow based vs. demand based energy-water modelling

    Science.gov (United States)

    Rozos, Evangelos; Nikolopoulos, Dionysis; Efstratiadis, Andreas; Koukouvinos, Antonios; Makropoulos, Christos

    2015-04-01

    The water flow in hydro-power generation systems is often used downstream to cover other type of demands like irrigation and water supply. However, the typical case is that the energy demand (operation of hydro-power plant) and the water demand do not coincide. Furthermore, the water inflow into a reservoir is a stochastic process. Things become more complicated if renewable resources (wind-turbines or photovoltaic panels) are included into the system. For this reason, the assessment and optimization of the operation of hydro-power systems are challenging tasks that require computer modelling. This modelling should not only simulate the water budget of the reservoirs and the energy production/consumption (pumped-storage), but should also take into account the constraints imposed by the natural or artificial water network using a flow routing algorithm. HYDRONOMEAS, for example, uses an elegant mathematical approach (digraph) to calculate the flow in a water network based on: the demands (input timeseries), the water availability (simulated) and the capacity of the transmission components (properties of channels, rivers, pipes, etc.). The input timeseries of demand should be estimated by another model and linked to the corresponding network nodes. A model that could be used to estimate these timeseries is UWOT. UWOT is a bottom up urban water cycle model that simulates the generation, aggregation and routing of water demand signals. In this study, we explore the potentials of UWOT in simulating the operation of complex hydrosystems that include energy generation. The evident advantage of this approach is the use of a single model instead of one for estimation of demands and another for the system simulation. An application of UWOT in a large scale system is attempted in mainland Greece in an area extending over 130×170 km². The challenges, the peculiarities and the advantages of this approach are examined and critically discussed.

  7. Friction and Wear of Nanoadditive-Based Biolubricants in Steel-Steel Sliding Contacts: A Comparative Study

    Science.gov (United States)

    Gupta, Rajeev Nayan; Harsha, A. P.

    2018-02-01

    The present work deals with the study of tribo-pair interaction in lubricated sliding contacts. By considering the environmental issues, the sunflower oil was extracted from the sunflower seeds and used as a base lubricant. The two types of the nanoadditives, i.e., CuO and CeO2, varying concentrations from 0.10 to 0.50% w/v were used to formulate the nanolubricants. The compatibility/synergism of the nanoadditives was examined from antifriction and antiwear behavior study with four-ball tester. Also, sunflower oil was modified by the chemical method to improve its fatty acid structure. A comparative tribological and compatibility study was also done in modified oil at similar concentration levels with both types of nanoparticles. The tribological test result exhibits 0.10% w/v concentration of the nanoadditive as optimum due to lowest wear scar and coefficient of friction. Higher concentration of the nanoparticles impaired the base oil performance. Different analytical tools were used to characterize the oil modification and worn surfaces. Moreover, the role of subsurface of the contacting material with the tribological performance has been reported.

  8. A New Method to Detect Driver Fatigue Based on EMG and ECG Collected by Portable Non-Contact Sensors

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2017-11-01

    Full Text Available Recently, detection and prediction on driver fatigue have become interest of research worldwide. In the present work, a new method is built to effectively evaluate driver fatigue based on electromyography (EMG and electrocardiogram (ECG collected by portable real-time and non-contact sensors. First, under the non-disturbance condition for driver’s attention, mixed physiological signals (EMG, ECG and artefacts are collected by non-contact sensors located in a cushion on the driver’s seat. EMG and ECG are effectively separated by FastICA, and de-noised by empirical mode decomposition (EMD. Then, three physiological features, complexity of EMG, complexity of ECG, and sample entropy (SampEn of ECG, are extracted and analysed. Principal components are obtained by principal components analysis (PCA and are used as independent variables. Finally, a mathematical model of driver fatigue is built, and the accuracy of the model is up to 91%. Moreover, based on the questionnaire, the calculation results of model are consistent with real fatigue felt by the participants. Therefore, this model can effectively detect driver fatigue.

  9. Triboelectret-based aeroelastic flutter energy harvesters

    Science.gov (United States)

    Perez, Matthias; Boisseau, Sebastien; Geisler, Matthias; Despesse, Ghislain; Reboud, Jean Luc

    2016-11-01

    This paper highlights some experimental results on several electrostatic membranes tested in a wind tunnel between 0 and 20m.s-1 for airflow energy harvesting. The main idea is to use the aeroelastic behavior of thin flexible films to induce simultaneously the capacitance variations and the polarization required by the triboelectric/electrostatic conversion. This technology provides thin and flexible devices and avoids the issue of electrets discharge. Our prototypes (energy harvesting chain, we have used a wireless sensor with temperature and acceleration measures coupled to a low power transmission (Bluetooth Low Energy) with reception on a smartphone.

  10. Energy concepts for self-supplying communities based on local and renewable energy sources

    DEFF Research Database (Denmark)

    Petersen, Jens-Phillip

    2016-01-01

    settings. The current case study presents a community energy concept for the inner-city of Elmshorn. By estimating the energy demand, consideration of local energy saving potentials, and available energy potentials within the community, it was possible to develop several energy system variants...... that virtually allow a heating energy and electricity supply fully based on local, renewable energy resources. The most feasible and cost-efficient variant is the use of local food production waste in a CHP plant feeding a district heating grid. The overall aim is to show that a self-sufficient heat...

  11. Influence of short chain organic acids and bases on the wetting properties and surface energy of submicrometer ceramic powders.

    Science.gov (United States)

    Neirinck, Bram; Soccol, Dimitri; Fransaer, Jan; Van der Biest, Omer; Vleugels, Jef

    2010-08-15

    The effect of short chained organic acids and bases on the surface energy and wetting properties of submicrometer alumina powder was assessed. The surface chemistry of treated powders was determined by means of Diffuse Reflectance Infrared Fourier Transform spectroscopy and compared to untreated powder. The wetting of powders was measured using a modified Washburn method, based on the use of precompacted powder samples. The geometric factor needed to calculate the contact angle was derived from measurements of the porous properties of the powder compacts. Contact angle measurements with several probe liquids before and after modification allowed a theoretical estimation of the surface energy based on the surface tension component theory. Trends in the surface energy components were linked to observations in infrared spectra. The results showed that the hydrophobic character of the precompacted powder depends on both the chain length and polar group of the modifying agent. Copyright 2010 Elsevier Inc. All rights reserved.

  12. Energy Based Acoustic Measurement Senors, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — This research focuses on fully developing energy density sensors that will yield a significant benefit both for measurements of interest to NASA, as well as for...

  13. Energy Based Acoustic Measurement Senors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This research focuses on fully developing energy density sensors that will yield a significant benefit both for measurements of interest to NASA, as well as for...

  14. Smart Home Energy Management Based on Zigbee

    OpenAIRE

    E.Mallikarjuna

    2015-01-01

    Today organizations use IEEE 802.15&Zigbee to effectively deliver solutions for a variety of areas including consumer electronic device control, energy management and efficiency home and commercial building automation as well as industrial plant management. The smart home energy network has gained widespread attentions due to its flexible integrati- ion into everyday life. This next generation green home system transparently unifies various home appliances smart sensors &wireless communicati...

  15. Contact materials for nanoelectronics

    KAUST Repository

    Alshareef, Husam N.

    2011-02-01

    In this article, we review current research activities in contact material development for electronic and nanoelectronic devices. A fundamental issue in contact materials research is to understand and control interfacial reactions and phenomena that modify the expected device performance. These reactions have become more challenging and more difficult to control as new materials have been introduced and as device sizes have entered the deep nanoscale. To provide an overview of this field of inquiry, this issue of MRS Bulletin includes articles on gate and contact materials for Si-based devices, junction contact materials for Si-based devices, and contact materials for alternate channel substrates (Ge and III-V), nanodevices. © 2011 Materials Research Society.

  16. Building and maintaining media contacts

    International Nuclear Information System (INIS)

    Fenton, Bob

    2000-01-01

    This presentation is answering the question: 'how does British Energy build and maintain its relationships with journalists in so many areas', not only the basic industrial correspondents that you would expect to have to deal with an industry British Energy, but those dealing with science and technology, the environment, personnel and training, city and financial, political, and on and on, and that is just the national press. Then add the local and regional media around power station sites - literally hundreds of contacts and you start to get an idea about the size of our media contact database. But it is managed it rather well. Every six months British Energy takes part in a survey run by one of the UK's leading market research companies who conducts a poll among journalists and then rate each company's performance. In the last three years British Energy has not been outside the top five in most categories, and in the top two in several. The answer is a lot of work over a long period of time. You cannot expect to build trusting relationships with a journalist overnight. At British Energy the key is being open and honest, and always available. Of course good media relations is not a one-way street, and there has to be some element of compromise if you are to achieve a relationship based on mutual trust

  17. Estimates of Social Contact in a Middle School Based on Self-Report and Wireless Sensor Data.

    Directory of Open Access Journals (Sweden)

    Molly Leecaster

    Full Text Available Estimates of contact among children, used for infectious disease transmission models and understanding social patterns, historically rely on self-report logs. Recently, wireless sensor technology has enabled objective measurement of proximal contact and comparison of data from the two methods. These are mostly small-scale studies, and knowledge gaps remain in understanding contact and mixing patterns and also in the advantages and disadvantages of data collection methods. We collected contact data from a middle school, with 7th and 8th grades, for one day using self-report contact logs and wireless sensors. The data were linked for students with unique initials, gender, and grade within the school. This paper presents the results of a comparison of two approaches to characterize school contact networks, wireless proximity sensors and self-report logs. Accounting for incomplete capture and lack of participation, we estimate that "sensor-detectable", proximal contacts longer than 20 seconds during lunch and class-time occurred at 2 fold higher frequency than "self-reportable" talk/touch contacts. Overall, 55% of estimated talk-touch contacts were also sensor-detectable whereas only 15% of estimated sensor-detectable contacts were also talk-touch. Contacts detected by sensors and also in self-report logs had longer mean duration than contacts detected only by sensors (6.3 vs 2.4 minutes. During both lunch and class-time, sensor-detectable contacts demonstrated substantially less gender and grade assortativity than talk-touch contacts. Hallway contacts, which were ascertainable only by proximity sensors, were characterized by extremely high degree and short duration. We conclude that the use of wireless sensors and self-report logs provide complementary insight on in-school mixing patterns and contact frequency.

  18. Energy Sharing Framework for Microgrid-Powered Cellular Base Stations

    KAUST Repository

    Farooq, Muhammad Junaid

    2017-02-07

    Cellular base stations (BSs) are increasingly becoming equipped with renewable energy generators to reduce operational expenditures and carbon footprint of wireless communications. Moreover, advancements in the traditional electricity grid allow two-way power flow and metering that enable the integration of distributed renewable energy generators at BS sites into a microgrid. In this paper, we develop an optimized energy management framework for microgrid-connected cellular BSs that are equipped with renewable energy generators and finite battery storage to minimize energy cost. The BSs share excess renewable energy with others to reduce the dependency on the conventional electricity grid. Three cases are investigated where the renewable energy generation is unknown, perfectly known, and partially known ahead of time. For the partially known case where only the statistics of renewable energy generation are available, stochastic programming is used to achieve a conservative solution. Results show the time varying energy management behaviour of the BSs and the effect of energy sharing between them.

  19. Dualism-Based Design of the Introductory Chinese MOOC "Kit de contact en langue chinoise"

    Science.gov (United States)

    Wang-Szilas, Jue; Bellassen, Joël

    2017-01-01

    This article reviews the existing Chinese language Massive Open Online Courses (MOOCs) and points out three problems in their design: the monism-based teaching method, the non-integration of cultural elements, and the lack of learner-learner interactions. It then presents the design principles of the Introductory Chinese MOOC in an attempt to…

  20. Contact angle and contact angle hysteresis measurements using the capillary bridge technique.

    Science.gov (United States)

    Restagno, Frédéric; Poulard, Christophe; Cohen, Céline; Vagharchakian, Laurianne; Léger, Liliane

    2009-09-15

    A new experimental technique is proposed to easily measure both advancing and receding contact angles of a liquid on a solid surface, with unprecedented accuracy. The technique is based on the analysis of the evolution of a capillary bridge formed between a liquid bath and a solid surface (which needs to be spherical) when the distance between the surface and the liquid bath is slowly varied. The feasibility of the technique is demonstrated using a low-energy perfluorinated surface with two different test liquids (water and hexadecane). A detailed description of both experimental procedures and computational modeling are given, allowing one to determine contact angle values. It is shown that the origin of the high accuracy of this technique relies on the fact that the contact angles are automatically averaged over the whole periphery of the contact. This method appears to be particularly adapted to the characterization of surfaces with very low contact angle hysteresis.

  1. Dynamic Behavior Analysis of Non-Contacting Hydrodynamic Finger Seal Based on Fluid-Solid-Interaction Method

    Directory of Open Access Journals (Sweden)

    Su Hua

    2018-01-01

    Full Text Available Finger seal is an advanced compliant seal and can be utilized to separate high (HP and low pressure (LP zones in high speed rotating shaft environment. The work to be presented concerns the dynamic behavior of a repetitive section of a two-layer finger seal with high-and padded low-pressure laminates. The dynamic performance of the finger seal are analyzed by the coupled fluid-solid-interaction (FSI simulations. By using the commercial software ANSYS-CFX, the numerical simulation results of interactions between the gas flow and fingers structural deformation are described when the radial periodic excitation from the shaft applies to the finger seal. And the gas film loading capacity, gas film stiffness and leakage varied with time are put forward in different working conditions. Compared with the dynamic performance analysis results based on equivalent dynamic method, the FSI dynamic analysis shows some different characteristics which are more accordance with actual circumstance. Moreover, it is shown that under low pressure differential and high rotation speed the non-contacting finger seal with advance features both in sealing effectiveness and potential unlimited life span can be obtained by rational structure design. But for the non-contacting finger seal with circumferential convergent pad working in high pressure and low rotating speed conditions, it is difficult to improve the sealing performance by the way of changing the structure parameters of finger seal. It is because the high pressure plays a major role on this sealing situation.

  2. Automated bone removal in CT angiography: Comparison of methods based on single energy and dual energy scans

    International Nuclear Information System (INIS)

    Straten, Marcel van; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; Lugt, Aad van der; Krestin, Gabriel P.; Niessen, Wiro J.

    2011-01-01

    Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic thorax phantom, acquired with a second generation dual source CT scanner. The methods differed by the way information on the presence of bone was obtained (either by using an additional, nonenhanced scan or by scanning with two tube voltages at the same time) and by the way the bone was removed from the CTA images (either by masking or subtracting the bone). The phantom contained parts which mimic vessels of various diameters in direct contact with bone. Both a quantitative and qualitative analysis of image quality after bone removal was performed. Image quality was quantified by the contrast-to-noise ratio (CNR) normalized to the square root of the dose (CNRD). At locations where vessels touch bone, the quality of the bone removal and the vessel preservation were visually assessed. The dual energy based methods were assessed with and without the addition of a 0.4 mm tin filter to the high voltage x-ray tube filtration. For each bone removal method, the dose required to obtain a certain CNR after bone removal was compared with the dose of a reference scan with the same CNR but without automated bone removal. The CNRD value of the reference scan was maximized by choosing the lowest tube voltage available. Results: All methods removed the bone completely. CNRD values were higher for the masking based methods than for the subtraction based methods. Single energy based methods had a higher CNRD value than the corresponding dual energy based methods. For the subtraction based dual energy method, tin filtration improved the CNRD value with approximately 50%. For the masking based dual energy method, it was easier to differentiate between iodine and bone when tin filtration

  3. Automated bone removal in CT angiography: Comparison of methods based on single energy and dual energy scans

    Energy Technology Data Exchange (ETDEWEB)

    Straten, Marcel van; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; Lugt, Aad van der; Krestin, Gabriel P.; Niessen, Wiro J. [Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Departments of Radiology and Medical Informatics, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Department of Radiology, University Medical Center Groningen, University of Groningen, P.O. Box 30.001, 9700 RB Groningen (Netherlands); Department of Radiology, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands); Departments of Radiology and Medical Informatics, Erasmus MC University Medical Center, P.O. Box 2040, 3000 CA Rotterdam (Netherlands)

    2011-11-15

    Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic thorax phantom, acquired with a second generation dual source CT scanner. The methods differed by the way information on the presence of bone was obtained (either by using an additional, nonenhanced scan or by scanning with two tube voltages at the same time) and by the way the bone was removed from the CTA images (either by masking or subtracting the bone). The phantom contained parts which mimic vessels of various diameters in direct contact with bone. Both a quantitative and qualitative analysis of image quality after bone removal was performed. Image quality was quantified by the contrast-to-noise ratio (CNR) normalized to the square root of the dose (CNRD). At locations where vessels touch bone, the quality of the bone removal and the vessel preservation were visually assessed. The dual energy based methods were assessed with and without the addition of a 0.4 mm tin filter to the high voltage x-ray tube filtration. For each bone removal method, the dose required to obtain a certain CNR after bone removal was compared with the dose of a reference scan with the same CNR but without automated bone removal. The CNRD value of the reference scan was maximized by choosing the lowest tube voltage available. Results: All methods removed the bone completely. CNRD values were higher for the masking based methods than for the subtraction based methods. Single energy based methods had a higher CNRD value than the corresponding dual energy based methods. For the subtraction based dual energy method, tin filtration improved the CNRD value with approximately 50%. For the masking based dual energy method, it was easier to differentiate between iodine and bone when tin filtration

  4. The French Connection: The First Large Population-Based Contact Survey in France Relevant for the Spread of Infectious Diseases.

    Directory of Open Access Journals (Sweden)

    Guillaume Béraud

    Full Text Available Empirical social contact patterns are essential to understand the spread of infectious diseases. To date, no such data existed for France. Although infectious diseases are frequently seasonal, the temporal variation of contact patterns has not been documented hitherto.COMES-F is the first French large-scale population survey, carried out over 3 different periods (February-March, April, April-May with some participants common to the first and the last period. Participants described their contacts for 2 consecutive days, and reported separately on professional contacts when typically over 20 per day.2033 participants reported 38 881 contacts (weighted median [first quartile-third quartile]: 8[5-14] per day, and 54 378 contacts with supplementary professional contacts (9[5-17]. Contrary to age, gender, household size, holidays, weekend and occupation, period of the year had little influence on the number of contacts or the mixing patterns. Contact patterns were highly assortative with age, irrespective of the location of the contact, and gender, with women having 8% more contacts than men. Although most contacts occurred at home and at school, the inclusion of professional contacts modified the structure of the mixing patterns. Holidays and weekends reduced dramatically the number of contacts, and as proxies for school closure, reduced R0 by 33% and 28%, respectively. Thus, school closures could have an important impact on the spread of close contact infections in France.Despite no clear evidence for temporal variation, trends suggest that more studies are needed. Age and gender were found important determinants of the mixing patterns. Gender differences in mixing patterns might help explain gender differences in the epidemiology of infectious diseases.

  5. Ship Integration of Energy Scavenging Technology for Sea Base Operations

    Science.gov (United States)

    2009-07-01

    Warfare Center Carderock Division Naval Research Enterprise Intern Program Sea Base Energy Scavenger Phillipines Raw Power Availability 0.10 1.00...Solar Radiation Energy Wave Height Energy Phillipines Raw Power Potential 0.10 1.00 10.00 100.00 1000.00 10000.00 100000.00 Jan Feb Mar Apr May Jun

  6. Multi-channel conduction in redox-based resistive switch modelled using quantum point contact theory

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, E., E-mail: enrique.miranda@uab.cat; Suñé, J. [Departament d' Enginyeria Electrònica, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallés, Barcelona (Spain); Mehonic, A.; Kenyon, A. J. [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom)

    2013-11-25

    A simple analytic model for the electron transport through filamentary-type structures in Si-rich silica (SiO{sub x})-based resistive switches is proposed. The model is based on a mesoscopic description and is able to account for the linear and nonlinear components of conductance that arise from both fully and partially formed conductive channels spanning the dielectric film. Channels are represented by arrays of identical scatterers whose number and quantum transmission properties determine the current magnitude in the low and high resistance states. We show that the proposed model not only reproduces the experimental current-voltage (I-V) characteristics but also the normalized differential conductance (dln(I)/dln(V)-V) curves of devices under test.

  7. An agent-based model for energy service companies

    International Nuclear Information System (INIS)

    Robinson, Marguerite; Varga, Liz; Allen, Peter

    2015-01-01

    Highlights: • An agent-based model for household energy efficiency upgrades is considered. • Energy service companies provide an alternative to traditional utility providers. • Household self-financing is a limiting factor to widespread efficiency upgrading. • Longer term service contracts can lead to reduced household energy costs. • Future energy price increases enable service providers to retain their customer base. - Abstract: The residential housing sector is a major consumer of energy accounting for approximately one third of carbon emissions in the United Kingdom. Achieving a sustainable, low-carbon infrastructure necessitates a reduced and more efficient use of domestic energy supplies. Energy service companies offer an alternative to traditional providers, which supply a single utility product to satisfy the unconstrained demand of end users, and have been identified as a potentially important actor in sustainable future economies. An agent-based model is developed to examine the potential of energy service companies to contribute to the large scale upgrading of household energy efficiency, which would ultimately lead to a more sustainable and secure energy infrastructure. The migration of households towards energy service companies is described by an attractiveness array, through which potential customers can evaluate the future benefits, in terms of household energy costs, of changing provider. It is shown that self-financing is a limiting factor to the widespread upgrading of residential energy efficiency. Greater reductions in household energy costs could be achieved by committing to longer term contracts, allowing upgrade costs to be distributed over greater time intervals. A steadily increasing cost of future energy usage lends an element of stability to the market, with energy service companies displaying the ability to retain customers on contract expiration. The model highlights how a greater focus on the provision of energy services, as

  8. Visible spectrum-based non-contact HRV and dPTT for stress detection

    Science.gov (United States)

    Kaur, Balvinder; Hutchinson, J. Andrew; Ikonomidou, Vasiliki N.

    2017-05-01

    Stress is a major health concern that not only compromises our quality of life, but also affects our physical health and well-being. Despite its importance, our ability to objectively detect and quantify it in a real-time, non-invasive manner is very limited. This capability would have a wide variety of medical, military, and security applications. We have developed a pipeline of image and signal processing algorithms to make such a system practical, which includes remote cardiac pulse detection based on visible spectrum videos and physiological stress detection based on the variability in the remotely detected cardiac signals. First, to determine a reliable cardiac pulse, principal component analysis (PCA) was applied for noise reduction and independent component analysis (ICA) was applied for source selection. To determine accurate cardiac timing for heart rate variability (HRV) analysis, a blind source separation method based least squares (LS) estimate was used to determine signal peaks that were closely related to R-peaks of the electrocardiogram (ECG) signal. A new metric, differential pulse transit time (dPTT), defined as the difference in arrival time of the remotely acquired cardiac signal at two separate distal locations, was derived. It was demonstrated that the remotely acquired metrics, HRV and dPTT, have potential for remote stress detection. The developed algorithms were tested against human subject data collected under two physiological conditions using the modified Trier Social Stress Test (TSST) and the Affective Stress Response Test (ASRT). This research provides evidence that the variability in remotely-acquired blood wave (BW) signals can be used for stress (high and mild) detection, and as a guide for further development of a real-time remote stress detection system based on remote HRV and dPTT.

  9. LCA of biomass-based energy systems

    DEFF Research Database (Denmark)

    Tonini, Davide; Astrup, Thomas Fruergaard

    2012-01-01

    environmental impacts in the 2050 scenarios, in particular upstream impacts from land use changes (LUCs), fertilizer use and NOx emissions from the transport sector were critical. Land occupation (including LUC effects) caused by energy crop production increased to a range of 600–2100 × 106 m2/PJ depending...... on the amounts and types of energy crops introduced. Use of fossil diesel in the transport sector appeared to be environmentally preferable over biodiesel for acidification, aquatic eutrophication and land occupation. For global warming, biodiesel production via Fischer–Tropsch was comparable with fossil diesel....

  10. Performance of HADDOCK and a simple contact-based protein-ligand binding affinity predictor in the D3R Grand Challenge 2

    Science.gov (United States)

    Kurkcuoglu, Zeynep; Koukos, Panagiotis I.; Citro, Nevia; Trellet, Mikael E.; Rodrigues, J. P. G. L. M.; Moreira, Irina S.; Roel-Touris, Jorge; Melquiond, Adrien S. J.; Geng, Cunliang; Schaarschmidt, Jörg; Xue, Li C.; Vangone, Anna; Bonvin, A. M. J. J.

    2018-01-01

    We present the performance of HADDOCK, our information-driven docking software, in the second edition of the D3R Grand Challenge. In this blind experiment, participants were requested to predict the structures and binding affinities of complexes between the Farnesoid X nuclear receptor and 102 different ligands. The models obtained in Stage1 with HADDOCK and ligand-specific protocol show an average ligand RMSD of 5.1 Å from the crystal structure. Only 6/35 targets were within 2.5 Å RMSD from the reference, which prompted us to investigate the limiting factors and revise our protocol for Stage2. The choice of the receptor conformation appeared to have the strongest influence on the results. Our Stage2 models were of higher quality (13 out of 35 were within 2.5 Å), with an average RMSD of 4.1 Å. The docking protocol was applied to all 102 ligands to generate poses for binding affinity prediction. We developed a modified version of our contact-based binding affinity predictor PRODIGY, using the number of interatomic contacts classified by their type and the intermolecular electrostatic energy. This simple structure-based binding affinity predictor shows a Kendall's Tau correlation of 0.37 in ranking the ligands (7th best out of 77 methods, 5th/25 groups). Those results were obtained from the average prediction over the top10 poses, irrespective of their similarity/correctness, underscoring the robustness of our simple predictor. This results in an enrichment factor of 2.5 compared to a random predictor for ranking ligands within the top 25%, making it a promising approach to identify lead compounds in virtual screening.

  11. Contact Center Manager Administration (CCMA)

    Data.gov (United States)

    Social Security Administration — CCMA is the server that provides a browser-based tool for contact center administrators and supervisors. It is used to manage and configure contact center resources...

  12. Energy monitoring based on human activity in the workplace

    Science.gov (United States)

    Mustafa, N. H.; Husain, M. N.; Abd Aziz, M. Z. A.; Othman, M. A.; Malek, F.

    2014-04-01

    Human behavior is the most important factor in order to manage energy usage. Nowadays, smart house technology offers a better quality of life by introducing automated appliance control and assistive services. However, human behaviors will contribute to the efficiency of the system. This paper will focus on monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior atb the workplace. Then, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy in efficient ways based on human behaviours. This scenario will lead to the positive impact in order to achieve the energy saving in the building and support the green environment.

  13. Energy monitoring system based on human activity in the workplace

    Science.gov (United States)

    Mustafa, Nur Hanim; Husain, Mohd Nor; Aziz, Mohamad Zoinol Abidin Abdul; Othman, Mohd Azlishah; Malek, Fareq

    2015-05-01

    Human behaviors always related to day routine activities in a smart house directly give the significant factor to manage energy usage in human life. An Addition that, the factor will contribute to the best efficiency of the system. This paper will focus on the monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior at working place. Besides that, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy saving based on human behaviors. This scenario will help to see the human activity in the workplace in order to get the energy saving and support world green environment.

  14. Differential Laser Doppler based Non-Contact Sensor for Dimensional Inspection with Error Propagation Evaluation

    Directory of Open Access Journals (Sweden)

    Ketsaya Vacharanukul

    2006-06-01

    Full Text Available To achieve dynamic error compensation in CNC machine tools, a non-contactlaser probe capable of dimensional measurement of a workpiece while it is being machinedhas been developed and presented in this paper. The measurements are automatically fedback to the machine controller for intelligent error compensations. Based on a well resolvedlaser Doppler technique and real time data acquisition, the probe delivers a very promisingdimensional accuracy at few microns over a range of 100 mm. The developed opticalmeasuring apparatus employs a differential laser Doppler arrangement allowing acquisitionof information from the workpiece surface. In addition, the measurements are traceable tostandards of frequency allowing higher precision.

  15. Energy-based modelling and control of wind energy conversion system with DFIG

    Science.gov (United States)

    Song, H. H.; Qu, Y. B.

    2011-02-01

    Focusing on wind energy conversion system (WECS) at the doubly-fed induction generator (DFIG) control level, a novel control approach was proposed to optimise wind energy capture from consideration of physical nature and energy relationship. According to energy flowing, the WECS was divided into several multi-ports energy conversion subsystems, and the structure matrices of the subsystems were elaborately designed. Based on this, port-controlled Hamiltonian models of the subsystems were obtained, and energy-based control using the models was provided to realise the machine side and the grid side control objectives of the WECS. The approach was applied on a 2 MW WECS, and compared with classical proportional-integral (PI) controller using MATLAB/Simulink. The results show that the energy-based control not only fully satisfies both side control requirements, but also has more robust control performances for a turbulent wind than the PI control.

  16. Availability-based payback method for energy efficiency measures

    OpenAIRE

    Kasprowicz, Robert; Schulz, Carolin

    2015-01-01

    Energy-efficient technologies can lead to high energy and monetary savings in numerous industries. However, a lot of potential identified in industries remains untapped due to comparatively short requested payback periods. Usually, companies base the calculation of their payback period on initial investment costs in conjunction with annual monetary energy savings. Energy efficiency measures, however, often lead to synergy effects which are not taken into account. Against this background, we i...

  17. Optimization of the Energy Level Alignment between the Photoactive Layer and the Cathode Contact Utilizing Solution-Processed Hafnium Acetylacetonate as Buffer Layer for Efficient Polymer Solar Cells.

    Science.gov (United States)

    Yu, Lu; Li, Qiuxiang; Shi, Zhenzhen; Liu, Hao; Wang, Yaping; Wang, Fuzhi; Zhang, Bing; Dai, Songyuan; Lin, Jun; Tan, Zhan'ao

    2016-01-13

    The insertion of an appropriate interfacial buffer layer between the photoactive layer and the contact electrodes makes a great impact on the performance of polymer solar cells (PSCs). Ideal interfacial buffer layers could minimize the interfacial traps and the interfacial barriers caused by the incompatibility between the photoactive layer and the electrodes. In this work, we utilized solution-processed hafnium(IV) acetylacetonate (Hf(acac)4) as an effective cathode buffer layer (CBL) in PSCs to optimize the energy level alignment between the photoactive layer and the cathode contact, with the short-circuit current density (Jsc), open-circuit voltage (Voc), and fill factor (FF) all simultaneously improved with Hf(acac)4 CBL, leading to enhanced power conversion efficiencies (PCEs). Ultraviolet photoemission spectroscopy (UPS) and scanning Kelvin probe microscopy (SKPM) were performed to confirm that the interfacial dipoles were formed with the same orientation direction as the built-in potential between the photoactive layer and Hf(acac)4 CBL, benefiting the exciton separation and electron transport/extraction. In addition, the optical characteristics and surface morphology of the Hf(acac)4 CBL were also investigated.

  18. Promoting Behavior-Based Energy Efficiency in Military Housing

    Energy Technology Data Exchange (ETDEWEB)

    AH McMakin; EL Malone; RE Lundgren

    1999-09-07

    The U.S. Department of Energy's Federal Energy Management Program (FEMP) helps agencies reduce the cost of doing business through energy efficiency, water conservation, and the use of solar and other renewable energy. As a large energy user, the U.S. military has been one of the government sectors of focus. Several military installations have shown substantial energy savings in past years. Most of these efficiency projects, however, have focused primarily on physical upgrades, technologies, and purchasing habits. Furthermost projects have focused on administrative and operational areas of energy use. Military residential housing, in particular, has received little formal attention for energy efficiency involving behaviors of the residents themselves. Behavior-based change is a challenging, but potentially fruitful area for energy conservation programs. However, behavioral change involves links with values, social networks and organizations, and new ways of thinking about living patterns. This handbook attempts to fill a gap by offering guidance for promoting such efforts.

  19. Energy output reduction and surface alteration of quartz tips following Er:YAG laser contact irradiation on soft and hard tissues in vitro.

    Science.gov (United States)

    Lin, Taichen; Kawamura, Rie; Aoki, Akira; Ichinose, Shizuko; Mizutani, Koji; Taniguchi, Yoichi; Eguro, Toru; Saito, Norihito; Izumi, Yuichi

    2016-01-01

    Though the Er:YAG laser (ErL) has been used in periodontal therapy, the irradiated tip damage has not been studied in detail. In this study, the change in the energy output, surface morphology, and temperature of quartz tips was evaluated following contact irradiation. Soft tissue, calculus on extracted human teeth, and porcine bone were irradiated by ErL for 60 min at 14.2 or 28.3 J/cm(2)/pulse and 20 Hz with or without water spray. The energy output ratio declined the most in the calculus group, followed by the bone and soft tissue groups with and/or without water spray. Carbon contamination was detected in all groups, and contamination by P, Ca, and/or other inorganic elements was observed in the calculus and bone groups. The rate of energy output reduction and the degree of surface alteration/contamination is variously influenced by the targeting tissue, temperature elevation of the tip and water spray.

  20. Non-contact analysis of the adsorptive ink capacity of nano silica pigments on a printing coating base.

    Science.gov (United States)

    Jiang, Bo; Huang, Yu Dong

    2014-01-01

    Near infrared spectra combined with partial least squares were proposed as a means of non-contact analysis of the adsorptive ink capacity of recording coating materials in ink jet printing. First, the recording coating materials were prepared based on nano silica pigments. 80 samples of the recording coating materials were selected to develop the calibration of adsorptive ink capacity against ink adsorption (g/m2). The model developed predicted samples in the validation set with r2  = 0.80 and SEP = 1.108, analytical results showed that near infrared spectra had significant potential for the adsorption of ink capacity on the recording coating. The influence of factors such as recording coating thickness, mass ratio silica: binder-polyvinyl alcohol and the solution concentration on the adsorptive ink capacity were studied. With the help of the near infrared spectra, the adsorptive ink capacity of a recording coating material can be rapidly controlled.

  1. Fabrication of four-point biped robot foot module based on contact-resistance force sensor and its evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Hyun Joon; Kim, Jong Ho; Kim, Dong Ki [Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of); Kwon, Young Ha [Kyung Hee University, Yongin (Korea, Republic of)

    2011-02-15

    This paper presents the design of robot foot module of four-point biped walking robot and its fabrication. The foot module has four sensor units based on contact-resistance force sensor. The thin-film-type force sensor is fabricated by coating resistive ink on thin polyimide film using silk screening technique. The simple structure is devised and fabricated to assemble the thin force sensor rigidly. The unit force sensor module is evaluated by the calibration setup to obtain the characteristics of repeatability and hysteresis. The sensor module presents hysteresis error of about 5% and repeatability error of about 0.37%. The calculated zero moment point (ZMP) of the foot module is also compared with the measured position using static load of 50 N. The maximum location error of ZMP is less than 10%. The robot foot module shows the possibility of applying it to humanoid walking.

  2. Fabrication of four-point biped robot foot module based on contact-resistance force sensor and its evaluation

    International Nuclear Information System (INIS)

    Kwon, Hyun Joon; Kim, Jong Ho; Kim, Dong Ki; Kwon, Young Ha

    2011-01-01

    This paper presents the design of robot foot module of four-point biped walking robot and its fabrication. The foot module has four sensor units based on contact-resistance force sensor. The thin-film-type force sensor is fabricated by coating resistive ink on thin polyimide film using silk screening technique. The simple structure is devised and fabricated to assemble the thin force sensor rigidly. The unit force sensor module is evaluated by the calibration setup to obtain the characteristics of repeatability and hysteresis. The sensor module presents hysteresis error of about 5% and repeatability error of about 0.37%. The calculated zero moment point (ZMP) of the foot module is also compared with the measured position using static load of 50 N. The maximum location error of ZMP is less than 10%. The robot foot module shows the possibility of applying it to humanoid walking

  3. Eu business-to-business trade contacts in waste management: a natural resource-based view approach

    Directory of Open Access Journals (Sweden)

    Ting Fa Margherita Chang

    2016-01-01

    Full Text Available This study analyzes the “Sewage and refuse disposal and sanitation” industry (Waste as a producer of services able to break down its negative externalities and transform them into an asset flow for competitive advantage. The conceptual lens used is the resource-based view (R-BV of the firm and in particular its spill-over, the “natural” R-BV. For EU-27 countries of the last decade, the Ghosh’s input-output model is applied to identify the valuable relationships concerning sale intermediate trade contacts (ITC. Furthermore Gini index and Lorenz curve demonstrate that Waste resource is quite concentrated and thus rare. This result suggests the necessity of developing initiatives aiming to strengthen the partnership between businesses, enhancing the sale-network profitability.

  4. Smart and Green Energy (SAGE) for Base Camps Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Engels, Matthias; Boyd, Paul A.; Koehler, Theresa M.; Goel, Supriya; Sisk, Daniel R.; Hatley, Darrel D.; Mendon, Vrushali V.; Hail, John C.

    2014-02-11

    The U.S. Army Logistics Innovation Agency’s (LIA’s) Smart and Green Energy (SAGE) for Base Camps project was to investigate how base camps’ fuel consumption can be reduced by 30% to 60% using commercial off-the-shelf (COTS) technologies for power generation, renewables, and energy efficient building systems. Field tests and calibrated energy models successfully demonstrated that the fuel reductions are achievable.

  5. Assessment of Energy Efficient and Model Based Control

    Science.gov (United States)

    2017-06-15

    ARL-TR-8042 ● JUNE 2017 US Army Research Laboratory Assessment of Energy -Efficient and Model- Based Control by Craig Lennon...originator. ARL-TR-8042 ● JUNE 2017 US Army Research Laboratory Assessment of Energy -Efficient and Model- Based Control by Craig...

  6. How the charge-neutrality level of interface states controls energy level alignment in cathode contacts of organic bulk-heterojunction solar cells.

    Science.gov (United States)

    Guerrero, Antonio; Marchesi, Luís F; Boix, Pablo P; Ruiz-Raga, Sonia; Ripolles-Sanchis, Teresa; Garcia-Belmonte, Germà; Bisquert, Juan

    2012-04-24

    Electronic equilibration at the metal-organic interface, leading to equalization of the Fermi levels, is a key process in organic optoelectronic devices. How the energy levels are set across the interface determines carrier extraction at the contact and also limits the achievable open-circuit voltage under illumination. Here, we report an extensive investigation of the cathode energy equilibration of organic bulk-heterojunction solar cells. We show that the potential to balance the mismatch between the cathode metal and the organic layer Fermi levels is divided into two contributions: spatially extended band bending in the organic bulk and voltage drop at the interface dipole layer caused by a net charge transfer. We scan the operation of the cathode under a varied set of conditions, using metals of different work functions in the range of ∼2 eV, different fullerene acceptors, and several cathode interlayers. The measurements allow us to locate the charge-neutrality level within the interface density of sates and calculate the corresponding dipole layer strength. The dipole layer withstands a large part of the total Fermi level mismatch when the polymer:fullerene blend ratio approaches ∼1:1, producing the practical alignment between the metal Fermi level and the charge-neutrality level. Origin of the interface states is linked with fullerene reduced molecules covering the metal contact. The dipole contribution, and consequently the band bending, is highly sensitive to the nature and amount of fullerene molecules forming the interface density of states. Our analysis provides a detailed picture of the evolution of the potentials in the bulk and the interface of the solar cell when forward voltage is applied or when photogeneration takes place.

  7. A Vision-Based Approach for Estimating Contact Forces: Applications to Robot-Assisted Surgery

    Directory of Open Access Journals (Sweden)

    C. W. Kennedy

    2005-01-01

    Full Text Available The primary goal of this paper is to provide force feedback to the user using vision-based techniques. The approach presented in this paper can be used to provide force feedback to the surgeon for robot-assisted procedures. As proof of concept, we have developed a linear elastic finite element model (FEM of a rubber membrane whereby the nodal displacements of the membrane points are measured using vision. These nodal displacements are the input into our finite element model. In the first experiment, we track the deformation of the membrane in real-time through stereovision and compare it with the actual deformation computed through forward kinematics of the robot arm. On the basis of accurate deformation estimation through vision, we test the physical model of a membrane developed through finite element techniques. The FEM model accurately reflects the interaction forces on the user console when the interaction forces of the robot arm with the membrane are compared with those experienced by the surgeon on the console through the force feedback device. In the second experiment, the PHANToM haptic interface device is used to control the Mitsubishi PA-10 robot arm and interact with the membrane in real-time. Image data obtained through vision of the deformation of the membrane is used as the displacement input for the FEM model to compute the local interaction forces which are then displayed on the user console for providing force feedback and hence closing the loop.

  8. Effect of Nano and Micro Friction Modifier Based Lubricants on Wear behavior between Steel-Steel Contacts

    Directory of Open Access Journals (Sweden)

    S. Bhaumik

    2017-03-01

    Full Text Available The wear and surface morphology between steel (EN24, 22-24Rc-steel (EN 31, 58-60Rc contacts was investigated in presence of friction modifiers based (micro-graphite/nano particles- multi wall carbon nano tubes and zinc oxide mineral oil. Though a decrease in wear was observed (upto a certain concentration of nano friction modifiers but a weight-gain in pins after the tests was observed for all tests with ZnO nanoparticles while weight loss was observed in tests with multi wall carbon nano tubes and graphite particles based oil samples. Surface characterization of the worn surfaces showed more surface deteriorations in case of mineral oil (no friction modifiers and mineral oil with graphite as compared with nano particles/tubes based lubricants. The occurrence of a tribo film due to the deposition of nano particle and the formation of a modified layer on the pin surfaces are likely to be responsible for the reduction of coefficient of friction and better surface roughness. Apart from investigating the wear behaviour between two steel surfaces under micro and nano particles based lubricant and analysing the surfaces of the samples a part of the work was also focussed on the weight gain after tribo tests with ZnO nano particle additions.

  9. Bioinspired model of mechanical energy harvesting based on flexoelectric membranes.

    Science.gov (United States)

    Rey, Alejandro D; Servio, P; Herrera-Valencia, E E

    2013-02-01

    Membrane flexoelectricity is an electromechanical coupling process that describes membrane electrical polarization due to bending and membrane bending under electric fields. In this paper we propose, formulate, and characterize a mechanical energy harvesting system consisting of a deformable soft flexoelectric thin membrane subjected to harmonic forcing from contacting bulk fluids. The key elements of the energy harvester are formulated and characterized, including (i) the mechanical-to-electrical energy conversion efficiency, (ii) the electromechanical shape equation connecting fluid forces with membrane curvature and electric displacement, and (iii) the electric power generation and efficiency. The energy conversion efficiency is cast as the ratio of flexoelectric coupling to the product of electric and bending elasticity. The device is described by a second-order curvature dynamics coupled to the electric displacement equation and as such results in mechanical power absorption with a resonant peak whose amplitude decreases with bending viscosity. The electric power generation is proportional to the conversion factor and the power efficiency decreases with frequency. Under high bending viscosity, the power efficiency increases with the conversion factor and under low viscosities it decreases with the conversion factor. The theoretical results presented contribute to the ongoing experimental efforts to develop mechanical energy harvesting from fluid flow energy through solid-fluid interactions and electromechanical transduction.

  10. Surface energy-tunable iso decyl acrylate based molds for low pressure-nanoimprint lithography

    Science.gov (United States)

    Tak, Hyowon; Tahk, Dongha; Jeong, Chanho; Lee, Sori; Kim, Tae-il

    2017-10-01

    We presented surface energy-tunable nanoscale molds for unconventional lithography. The mold is highly robust, transparent, has a minimized haze, does not contain additives, and is a non-fluorinated isodecyl acrylate and trimethylolpropane triacrylate based polymer. By changing the mixing ratio of the polymer components, the cross-linking density, mechanical modulus, and surface energy (crucial factors in low pressure ((1-2) × 105 N m-2) low pressure-nanoimprint lithography (LP-NIL)), can be controlled. To verify these properties of the molds, we also characterized the surface energy by measuring the contact angles and calculating the work of adhesion among the wafer, polymer film, and mold for successful demolding in nanoscale structures. Moreover, the molds showed high optical clarity and precisely tunable mechanical and surface properties, capable of replicating sub-100 nm patterns by thermal LP-NIL and UV-NIL.

  11. An Energy Integrated Dispatching Strategy of Multi- energy Based on Energy Internet

    Science.gov (United States)

    Jin, Weixia; Han, Jun

    2018-01-01

    Energy internet is a new way of energy use. Energy internet achieves energy efficiency and low cost by scheduling a variety of different forms of energy. Particle Swarm Optimization (PSO) is an advanced algorithm with few parameters, high computational precision and fast convergence speed. By improving the parameters ω, c1 and c2, PSO can improve the convergence speed and calculation accuracy. The objective of optimizing model is lowest cost of fuel, which can meet the load of electricity, heat and cold after all the renewable energy is received. Due to the different energy structure and price in different regions, the optimization strategy needs to be determined according to the algorithm and model.

  12. Late and very-late first-contact schizophrenia and the risk of dementia--a nationwide register based study

    DEFF Research Database (Denmark)

    Kørner, Alex; Lopez, Ana Garcia; Lauritzen, Lise

    2009-01-01

    OBJECTIVE: To examine whether late and very-late first-contact schizophrenia carry a risk for later development of dementia. METHODS: By linkage of the psychiatric and the somatic nation-wide registers of all out- and in-patients with hospital contact in Denmark, we identified all patients...... with first ever contact during the period from January 1994 to December 2001 with one of the index main diagnoses: late (age >or=40) and very-late first-contact (age >or=60) schizophrenia. First contact osteoarthritis patients as well as data on the general population were used as controls. The first...... diagnosis of dementia for each individual at discharge or at out-patient contact was established. The probability of getting a dementia diagnosis is estimated using Poisson regression models with dementia as the outcome of interest. RESULTS: Twelve thousand six hundred and sixteen and 7,712 individuals were...

  13. Model Property Based Material Balance and Energy Conservation Analysis for Process Industry Energy Transfer Systems

    Directory of Open Access Journals (Sweden)

    Fumin Ma

    2015-10-01

    Full Text Available Conventional historical data based material and energy balance analyses are static and isolated computations. Such methods cannot embody the cross-coupling effect of energy flow, material flow and information flow in the process industry; furthermore, they cannot easily realize the effective evaluation and comparison of different energy transfer processes by alternating the model module. In this paper, a novel method for material balance and energy conservation analysis of process industry energy transfer system is developed based on model property. Firstly, a reconfigurable energy transfer process model, which is independent of energy types and energy-consuming equipment, is presented from the viewpoint of the cross-coupling effect of energy flow, material flow and information flow. Thereafter the material balance determination is proposed based on both a dynamic incidence matrix and dynamic balance quantity. Moreover, the model-weighted conservation determination theorem is proved, and the energy efficiency analysis method is also discussed. Results confirmed the efficacy of the proposed methods, confirming its potential for use by process industry in energy efficiency analyses.

  14. Measurement of energy efficiency based on economic foundations

    International Nuclear Information System (INIS)

    Filippini, Massimo; Hunt, Lester C.

    2015-01-01

    Energy efficiency policy is seen as a very important activity by almost all policy makers. In practical energy policy analysis, the typical indicator used as a proxy for energy efficiency is energy intensity. However, this simple indicator is not necessarily an accurate measure given changes in energy intensity are a function of changes in several factors as well as ‘true’ energy efficiency; hence, it is difficult to make conclusions for energy policy based upon simple energy intensity measures. Related to this, some published academic papers over the last few years have attempted to use empirical methods to measure the efficient use of energy based on the economic theory of production. However, these studies do not generally provide a systematic discussion of the theoretical basis nor the possible parametric empirical approaches that are available for estimating the level of energy efficiency. The objective of this paper, therefore, is to sketch out and explain from an economic perspective the theoretical framework as well as the empirical methods for measuring the level of energy efficiency. Additionally, in the second part of the paper, some of the empirical studies that have attempted to measure energy efficiency using such an economics approach are summarized and discussed.

  15. An Asset-Based Approach to Tribal Community Energy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez, Rachael A. [Pratt Inst., Brooklyn, NY (United States). City and Regional Planning; Martino, Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials, Devices, and Energy Technologies; Begay, Sandra K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Materials, Devices, and Energy Technologies

    2016-08-01

    Community energy planning is a vital component of successful energy resource development and project implementation. Planning can help tribes develop a shared vision and strategies to accomplish their energy goals. This paper explores the benefits of an asset-based approach to tribal community energy planning. While a framework for community energy planning and federal funding already exists, some areas of difficulty in the planning cycle have been identified. This paper focuses on developing a planning framework that offsets those challenges. The asset-based framework described here takes inventory of a tribe’s capital assets, such as: land capital, human capital, financial capital, and political capital. Such an analysis evaluates how being rich in a specific type of capital can offer a tribe unique advantages in implementing their energy vision. Finally, a tribal case study demonstrates the practical application of an asset-based framework.

  16. Energy Data Base: corporate author entries

    International Nuclear Information System (INIS)

    Hendricks, P.L.

    1982-08-01

    Corporate author entries provide a means for consistent citing of the names of organizations in bibliographic records in the data bases of the DOE Technical Information Center. These entries serve as guides for users of the DOE/RECON computerized data bases who want to locate information originating in particular organizations

  17. Spectroscopic On-Line Monitoring of Cu/W Contacts Erosion in HVCBs Using Optical-Fibre Based Sensor and Chromatic Methodology.

    Science.gov (United States)

    Wang, Zhixiang; Jones, Gordon R; Spencer, Joseph W; Wang, Xiaohua; Rong, Mingzhe

    2017-03-06

    Contact erosion is one of the most crucial factors affecting the electrical service lifetime of high-voltage circuit breakers (HVCBs). On-line monitoring the contacts' erosion degree is increasingly in demand for the sake of condition based maintenance to guarantee the functional operation of HVCBs. A spectroscopic monitoring system has been designed based upon a commercial 245 kV/40 kA S F 6 live tank circuit breaker with copper-tungsten (28 wt % and 72 wt %) arcing contacts at atmospheric S F 6 pressure. Three optical-fibre based sensors are used to capture the time-resolved spectra of arcs. A novel approach using chromatic methods to process the time-resolved spectral signal has been proposed. The processed chromatic parameters have been interpreted to show that the time variation of spectral emission from the contact material and quenching gas are closely correlated to the mass loss and surface degradation of the plug arcing contact. The feasibility of applying this method to online monitoring of contact erosion is indicated.

  18. Sea wave energy based in nanotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Duque, Carlos

    2010-09-15

    Application on which it turns east document is the recovery of the energy of the sea waves turning it into electricity by means of the combination of nano-piezoelectric and condensing, the system would be seen like a compound floating fabric of million piezoelectric crystals that turn the oscillating movement of the sea into micro-electrical signals that they are added and they left by means cables to the surface where electronics devices classified to the load of condensers, from the electricity is confined and later is invested and synchronize itself with the great national mains.

  19. Mechanical Contact Experiments and Simulations

    DEFF Research Database (Denmark)

    Nielsen, Chris Valentin; Martins, P; Zhang, W.

    2011-01-01

    . The overall investigation serves for testing and validating the numerical implementation of the mechanical contact, which is one of the main contributions to a system intended for 3D simulation of resistance welding. Correct modelling of contact between parts to be welded, as well as contact with electrodes...... geometries and different materials are analyzed including contact between dissimilar materials. The numerical implementation is performed with a finite element computer program based on the irreducible flow formulation, and contact between deformable objects is modelled by applying the penalty method......, is crucial for satisfactory modelling of the resistance welding process. The resistance heating at the contact interfaces depends on both contact area and pressure, and as the contact areas develop dynamically, the presented tests are relevant for assessing the validity and accuracy of the mechanical contact...

  20. Contact hysteroscopy.

    Science.gov (United States)

    Baggish, M S; Barbot, J

    1983-06-01

    In 1907 innovations in optics and illumination made by Maximilian Nitze were applied to hysteroscopy by Charles David, who wrote a treatise of hysteroscopy. David improved illumination by placing an electric incandescent bulb at the intrauterine end of his endoscope and also sealed the distal end of the tube with a piece of glass. The history of the contact endoscope that the authors personally used is connected to the invention by Vulmiere (1952) of a revolutionary illumination process in endoscopy--the "cold light" process. The components of cold light consist of a powerful external light source that is transmitted via a special optical guide into the endometrial cavity. The 1st application of his principle (1963) was an optical trochar contained in a metallic sheath. This simple endoscope was perfected, and in 1973 Barbot and Parent, in France, began to use it to examine the uterine cavity. Discussion focuses on methods, instrumentation, method for examination (grasping the instrument, setup, light source, anesthesia, dilatation, technique, and normal endometrium); cervical neoplasia; nonneoplastic lesions of the endometrium (endometrial polyp, submucous myoma, endometrial hyperplasia); intrauterine device localization; neoplastic lesions of the endometrium; precursors (adenocarcinoma); hysteroscopy in pregnancy (embryoscopy, hydatidiform mole, postpartum hemorrhage, incomplete abortion, spontaneous abortion, induced abortions, and amnioscopy); and examinations of children and infants. The contact endoscope must make light contact with the structure to be viewed. The principles of contact endoscopy depend on an interpretation of color, contour, vascular pattern, and a sense of touch. These are computed together and a diagnosis is made on the basis of previously learned clinical pathologic correlations. The contact endoscope is composed of 3 parts: an optical guide; a cylindric chamber that collects and traps ambient light; and a magnifying eyepiece. The phase of

  1. Risks of Allergic Contact Dermatitis Elicited by Nickel, Chromium, and Organic Sensitizers: Quantitative Models Based on Clinical Patch Test Data.

    Science.gov (United States)

    Bogen, Kenneth T; Garry, Michael R

    2017-10-11

    Risks of allergic contact dermatitis (ACD) from consumer products intended for extended (nonpiercing) dermal contact are regulated by E.U. Directive EN 1811 that limits released Ni to a weekly equivalent dermal load of ≤0.5 μg/cm 2 . Similar approaches for thousands of known organic sensitizers are hampered by inability to quantify respective ACD-elicitation risk levels. To help address this gap, normalized values of cumulative risk for eliciting a positive ("≥+") clinical patch test response reported in 12 studies for a total of n = 625 Ni-sensitized patients were modeled in relation to observed ACD-eliciting Ni loads, yielding an approximate lognormal (LN) distribution with a geometric mean and standard deviation of GM Ni = 15 μg/cm 2 and GSD Ni = 8.0, respectively. Such data for five sensitizers (including formaldehyde and 2-hydroxyethyl methacrylate) were also ∼LN distributed, but with a common GSD value equal to GSD Ni and with heterogeneous sensitizer-specific GM values each defining a respective ACD-eliciting potency GM Ni /GM relative to Ni. Such potencies were also estimated for nine (meth)acrylates by applying this general LN ACD-elicitation risk model to respective sets of fewer data. ACD-elicitation risk patterns observed for Cr(VI) (n = 417) and Cr(III) (n = 78) were fit to mixed-LN models in which ∼30% and ∼40% of the most sensitive responders, respectively, were estimated to exhibit a LN response also governed by GSD Ni . The observed common LN-response shape parameter GSD Ni may reflect a common underlying ACD mechanism and suggests a common interim approach to quantitative ACD-elicitation risk assessment based on available clinical data. © 2017 Society for Risk Analysis.

  2. Contact and fumigant toxicity of a botanical-based feeding deterrent of the stable fly, Stomoxys calcitrans (Diptera: Muscidae).

    Science.gov (United States)

    Zhu, Junwei J; Li, Andrew Y; Pritchard, Sara; Tangtrakulwanich, Khanobporn; Baxendale, Frederick P; Brewer, Gary

    2011-09-28

    The stable fly, Stomoxys calcitrans (L.), has been considered one of the most serious biting flies of confined and pastured livestock. The economic losses caused by the stable fly to the cattle industry in the United States exceed $2 billion annually. Current practices for managing stable flies using insecticides provide only marginal control. Insecticide resistance has also been recently reported in stable flies. The present study reports the use of plant-based insecticides, for example, essential oils, as alternatives for managing this fly pest. The toxicity of several plant essential oils and selected ingredient compounds was evaluated by contact and fumigant toxicity bioassays. Catnip oil (20 mg dosage) showed the highest toxicity against stable flies, the shortest knock-down time (∼7 min), and the quickest lethal time (∼19 min). Toxicity levels similar to catnip oil were found among three insect repellent compounds (N,N-diethyl-3-methylbenzamide, 2-methylpiperidinyl-3-cyclohexene-1-carboxamide, (1S,2'S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide). No differences in knock-down and lethal times were found among the catnip oil and its two active ingredient compounds. Similar stable fly mortality was observed using a 20 mg dose of catnip oil in a modified K&D system and a fumigant jar. When catnip oil was topically applied to stable flies, the least lethal dose was 12.5 μg/fly, and a 50 μg/fly dose resulted in 100% mortality. The blood-feeding behavior of stable flies was also negatively affected by the topical application of catnip oil, and the effect was dose-dependent. This study demonstrated that catnip oil has both contact and fumigant toxicity against the stable fly and thus has the potential as an alternative for stable fly control.

  3. Using a consensus approach based on the conservation of inter-residue contacts to rank CAPRI models

    KAUST Repository

    Vangone, Anna

    2013-10-17

    Herein we propose the use of a consensus approach, CONSRANK, for ranking CAPRI models. CONSRANK relies on the conservation of inter-residue contacts in the analyzed decoys ensemble. Models are ranked according to their ability to match the most frequently observed contacts. We applied CONSRANK to 19 CAPRI protein-protein targets, covering a wide range of prediction difficulty and involved in a variety of biological functions. CONSRANK results are consistently good, both in terms of native-like (NL) solutions ranked in the top positions and of values of the Area Under the receiver operating characteristic Curve (AUC). For targets having a percentage of NL solutions above 3%, an excellent performance is found, with AUC values approaching 1. For the difficult target T46, having only 3.4% NL solutions, the number of NL solutions in the top 5 and 10 ranked positions is enriched by a factor 30, and the AUC value is as high as 0.997. AUC values below 0.8 are only found for targets featuring a percentage of NL solutions within 1.1%. Remarkably, a false consensus emerges only in one case, T42, which happens to be an artificial protein, whose assembly details remain uncertain, based on controversial experimental data. We also show that CONSRANK still performs very well on a limited number of models, provided that more than 1 NL solution is included in the ensemble, thus extending its applicability to cases where few dozens of models are available.© 2013 Wiley Periodicals, Inc.

  4. Different cytotoxicity responses to antimicrobial nanosilver coatings when comparing extract-based and direct-contact assays.

    Science.gov (United States)

    Sussman, Eric M; Casey, Brendan J; Dutta, Debargh; Dair, Benita J

    2015-06-01

    This study was performed to understand how the choice of cytotoxicity assay format affects the observed biocompatibility of nanosilver (nAg). nAg coatings are physical coatings containing silver (Ag) that have feature sizes of 100 nm or less, often in the form of nanoparticles or grains. They are used on medical devices to prevent infection, but in spite of this intended benefit, observations of potential cytotoxicity from nAg have been reported in numerous published studies. For medical device regulation, cytotoxicity testing is part of a biocompatibility evaluation, in which specific test methods are chosen based on the technological characteristics and intended use of a device. For this study, nAg-coated tissue culture polystyrene surfaces were prepared using magnetron sputter coating, resulting in nAg films of 0.2 to 311 µg cm(-2) Ag. These coatings exhibited nanometer-scale morphologies and demonstrated a > 4log10 reduction in Escherichia coli viability. It was observed that extracts of nAg caused no cytotoxicity to L929 mouse fibroblasts, but cells cultured directly on nAg coatings (direct-contact assay format) showed a dose-dependent reduction in viability by up to 100% (P cytotoxic over time, probably owing to the reaction with cell culture media and serum (six-fold cytotoxicity reductions observed over a 24-h period). These findings highlight the potential value of direct-contact cytotoxicity testing for nAg in predicting biological interactions with cells or tissue in vivo. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  5. Recent Progress on PZT Based Piezoelectric Energy Harvesting Technologies

    Directory of Open Access Journals (Sweden)

    Min-Gyu Kang

    2016-02-01

    Full Text Available Energy harvesting is the most effective way to respond to the energy shortage and to produce sustainable power sources from the surrounding environment. The energy harvesting technology enables scavenging electrical energy from wasted energy sources, which always exist everywhere, such as in heat, fluids, vibrations, etc. In particular, piezoelectric energy harvesting, which uses a direct energy conversion from vibrations and mechanical deformation to the electrical energy, is a promising technique to supply power sources in unattended electronic devices, wireless sensor nodes, micro-electronic devices, etc., since it has higher energy conversion efficiency and a simple structure. Up to now, various technologies, such as advanced materials, micro- and macro-mechanics, and electric circuit design, have been investigated and emerged to improve performance and conversion efficiency of the piezoelectric energy harvesters. In this paper, we focus on recent progress of piezoelectric energy harvesting technologies based on PbZrxTi1-xO3 (PZT materials, which have the most outstanding piezoelectric properties. The advanced piezoelectric energy harvesting technologies included materials, fabrications, unique designs, and properties are introduced to understand current technical levels and suggest the future directions of piezoelectric energy harvesting.

  6. Energy-analysis of the total nuclear energy cycle based on light water reactors

    International Nuclear Information System (INIS)

    Kistemaker, J.

    1975-01-01

    The energy economy of the total nuclear energy cycle is investigated. Attention is paid to the importance of fossil fuel saving by using nuclear energy. The energy analysis is based on the construction and operation of power plants with an electric output of 1000MWe. Light water moderated reactors with a 2.7 - 3.2% enriched uranium core are considered. Additionally, the whole fuel cycle including ore winning and refining, enrichment and fuel element manufacturing and reprocessing has been taken into account. Neither radioactive waste storage problems nor safety problems related to the nuclear energy cycle and safeguarding have been dealt with, as exhaustive treatments can be found elswhere

  7. Optimal ''image-based'' weighting for energy-resolved CT

    International Nuclear Information System (INIS)

    Schmidt, Taly Gilat

    2009-01-01

    This paper investigates a method of reconstructing images from energy-resolved CT data with negligible beam-hardening artifacts and improved contrast-to-nosie ratio (CNR) compared to conventional energy-weighting methods. Conceptually, the investigated method first reconstructs separate images from each energy bin. The final image is a linear combination of the energy-bin images, with the weights chosen to maximize the CNR in the final image. The optimal weight of a particular energy-bin image is derived to be proportional to the contrast-to-noise-variance ratio in that image. The investigated weighting method is referred to as ''image-based'' weighting, although, as will be described, the weights can be calculated and the energy-bin data combined prior to reconstruction. The performance of optimal image-based energy weighting with respect to CNR and beam-hardening artifacts was investigated through simulations and compared to that of energy integrating, photon counting, and previously studied optimal ''projection-based'' energy weighting. Two acquisitions were simulated: dedicated breast CT and a conventional thorax scan. The energy-resolving detector was simulated with five energy bins. Four methods of estimating the optimal weights were investigated, including task-specific and task-independent methods and methods that require a single reconstruction versus multiple reconstructions. Results demonstrated that optimal image-based weighting improved the CNR compared to energy-integrating weighting by factors of 1.15-1.6 depending on the task. Compared to photon-counting weighting, the CNR improvement ranged from 1.0 to 1.3. The CNR improvement factors were comparable to those of projection-based optimal energy weighting. The beam-hardening cupping artifact increased from 5.2% for energy-integrating weighting to 12.8% for optimal projection-based weighting, while optimal image-based weighting reduced the cupping to 0.6%. Overall, optimal image-based energy weighting

  8. Management of a power system based on renewable energy

    Directory of Open Access Journals (Sweden)

    Ronay Karoly

    2012-06-01

    Full Text Available This article main purpose is to highlight the main advantage of the hardware and software implementation for an energy management system based on renewable energy sources. By using implemented and dedicated hardware and software the evolution of energy production and consumption can be monitored. The advantages of such system are highlighted by the results obtained from experimental simulations. An experimental model for the power system based on renewable energy sources was implemented, where the actual status of the system in different situations when the equipments change their own statuses can be shown.

  9. Optimal selection among different domestic energy consumption patterns based on energy and exergy analysis

    International Nuclear Information System (INIS)

    Lu, S.; Wu, J.Y.

    2010-01-01

    In China market, people have many choices for air conditioning of their apartments, including heat-pump systems or gas-fired boilers for heating and air conditioners for cooling. Domestic hot water is usually provided by domestic water heaters making use of electricity or natural gas, which are known for their great energy costs. These systems consume much energy and increase the total cost of required domestic energy. A novel system combining heat pump with water heater is proposed in this paper, and it is named domestic energy system. The system can realize the provision of space heating, cooling and domestic hot water throughout a year. Based on different types of air conditioners, space heating equipments and water heaters, domestic energy consumption patterns are concluded to be eight categories. This study describes and compares the eight domestic energy consumption patterns by economic analysis and prime energy analysis method. Results show that the domestic energy system can provide good economy and save energy significantly. Furthermore, exergy analysis method is employed to compare the exergy efficiencies of different energy consumption systems. The results show that the domestic energy system has the highest energy conversion efficiency and can make remarkable contribution to social energy saving.

  10. Energy-efficiency based classification of the manufacturing workstation

    Science.gov (United States)

    Frumuşanu, G.; Afteni, C.; Badea, N.; Epureanu, A.

    2017-08-01

    EU Directive 92/75/EC established for the first time an energy consumption labelling scheme, further implemented by several other directives. As consequence, nowadays many products (e.g. home appliances, tyres, light bulbs, houses) have an EU Energy Label when offered for sale or rent. Several energy consumption models of manufacturing equipments have been also developed. This paper proposes an energy efficiency - based classification of the manufacturing workstation, aiming to characterize its energetic behaviour. The concept of energy efficiency of the manufacturing workstation is defined. On this base, a classification methodology has been developed. It refers to specific criteria and their evaluation modalities, together to the definition & delimitation of energy efficiency classes. The energy class position is defined after the amount of energy needed by the workstation in the middle point of its operating domain, while its extension is determined by the value of the first coefficient from the Taylor series that approximates the dependence between the energy consume and the chosen parameter of the working regime. The main domain of interest for this classification looks to be the optimization of the manufacturing activities planning and programming. A case-study regarding an actual lathe classification from energy efficiency point of view, based on two different approaches (analytical and numerical) is also included.

  11. A Framework for Better Understanding and Enhancing Direct Contact Membrane Distillation (DCMD) in Terms of Module Design, Cost Analysis and Energy Required

    KAUST Repository

    AbuHannoud, Ali

    2011-07-01

    Water is becoming scarcer and several authors have highlighted the upcoming problem of higher water salinity and the difficulty of treating and discharging water. Moreover, current discoveries of problems with chemicals that have been used for pretreating or post-treating water alerted scientists to research better solutions to treat water. Membrane distillation (MD) is a promising technology that might replace current processes as it has lower pretreatment requirements combined with a tremendous ability to treat a wide range of feed sources while producing very high product quality. If it enters the market, it will have a big influence on all products, from food industry to spaceflight. However, there are several problems which make MD a hot topic for research. One of them is the question about the real cost of MD in terms of heating feed and cooling distillate over time with respect to product quantity and quality. In this work, extensive heating and cooling analyses are covered to answer this question in order to enhance the MD process. Results show energy cost to produce water and the main source of energy loss for direct contact membrane distillation (DCMD), and several suggestions are made in order to better understand and hence enhance the process.

  12. Classification of hand eczema: clinical and aetiological types. Based on the guideline of the Danish Contact Dermatitis Group

    DEFF Research Database (Denmark)

    Johansen, Jeanne Duus; Hald, Marianne; Andersen, Bo Lasthein

    2011-01-01

    aetiological diagnosis. Results. Irritant contact dermatitis was most frequent in chronic, dry fissured hand eczema (44.3%), pulpitis (41.7%), and nummular hand eczema (40.9%), whereas allergic contact dermatitis dominated in vesicular types of hand eczema, with recurrent (35%) and few (24.2%) eruptions...

  13. Six Open Questions about the Migration of Engineered Nano-Objects from Polymer-Based Food Contact Materials: A Review

    DEFF Research Database (Denmark)

    Jokar, Maryam; Pedersen, Gitte Alsing; Löschner, Katrin

    2017-01-01

    The use of nanomaterials in food contact applications has created enormous interest in recent years. The potential migration of engineered nano-objects (ENOs) from food contact materials (FCMs) is one of the most important concerns regarding potential human exposure to ENOs and health risks...

  14. Bases for the Creation of Electric Energy Price Estimate Model

    International Nuclear Information System (INIS)

    Toljan, I.; Klepo, M.

    1995-01-01

    The paper presents the basic principles for the creation and introduction of a new model for the electric energy price estimate and its significant influence on the tariff system functioning. There is also a review of the model used presently for the electric energy price estimate which is based on the model of objectivized values of electric energy plants and production, transmission and distribution facilities, followed by proposed changes which would result in functional and organizational improvements within the electric energy system as the most complex subsystem of the whole power system. The model is based on substantial and functional connection of the optimization and analysis system with the electric energy economic dispatching, including marginal cost estimate and their influence on the tariff system as the main means in achieving better electric energy system's functioning quality. (author). 10 refs., 2 figs

  15. Energy-Based Acoustic Source Localization Methods: A Survey

    Directory of Open Access Journals (Sweden)

    Wei Meng

    2017-02-01

    Full Text Available Energy-based source localization is an important problem in wireless sensor networks (WSNs, which has been studied actively in the literature. Numerous localization algorithms, e.g., maximum likelihood estimation (MLE and nonlinear-least-squares (NLS methods, have been reported. In the literature, there are relevant review papers for localization in WSNs, e.g., for distance-based localization. However, not much work related to energy-based source localization is covered in the existing review papers. Energy-based methods are proposed and specially designed for a WSN due to its limited sensor capabilities. This paper aims to give a comprehensive review of these different algorithms for energy-based single and multiple source localization problems, their merits and demerits and to point out possible future research directions.

  16. Effect of surface tension on the behavior of adhesive contact based on Lennard-Jones potential law

    Science.gov (United States)

    Zhu, Xinyao; Xu, Wei

    2018-02-01

    The present study explores the effect of surface tension on adhesive contact behavior where the adhesion is interpreted by long-range intermolecular forces. The adhesive contact is analyzed using the equivalent system of a rigid sphere and an elastic half space covered by a membrane with surface tension. The long-range intermolecular forces are modeled with the Lennard‒Jones (L‒J) potential law. The current adhesive contact issue can be represented by a nonlinear integral equation, which can be solved by Newton‒Raphson method. In contrast to previous studies which consider intermolecular forces as short-range, the present study reveals more details of the features of adhesive contact with surface tension, in terms of jump instabilities, pull-off forces, pressure distribution within the contact area, etc. The transition of the pull-off force is not only consistent with previous studies, but also presents some new interesting characteristics in the current situation.

  17. Ionic liquid-based green processes for energy production.

    Science.gov (United States)

    Zhang, Suojiang; Sun, Jian; Zhang, Xiaochun; Xin, Jiayu; Miao, Qingqing; Wang, Jianji

    2014-11-21

    To mitigate the growing pressure on resource depletion and environment degradation, the development of green processes for the production of renewable energy is highly required. As a class of novel and promising media, ionic liquids (ILs) have shown infusive potential applications in energy production. Aiming to offer a critical overview regarding the new challenges and opportunities of ILs for developing green processes of renewable energy, this article emphasises the role of ILs as catalysts, solvents, or electrolytes in three broadly interesting energy production processes from renewable resources, such as CO2 conversion to fuels and fuel additives, biomass pretreatment and conversion to biofuels, as well as solar energy and energy storage. It is expected that this article will stimulate a generation of new ideas and new technologies in IL-based renewable energy production.

  18. An Automated Energy Detection Algorithm Based on Consecutive Mean Excision

    Science.gov (United States)

    2018-01-01

    ARL-TR-8268 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm Based on Consecutive Mean Excision...not return it to the originator. ARL-TR-8268 ● JAN 2018 US Army Research Laboratory An Automated Energy Detection Algorithm...2018 2. REPORT TYPE Technical Report 3. DATES COVERED (From - To) 1 October 2016–30 September 2017 4. TITLE AND SUBTITLE An Automated Energy

  19. Energy Efficient Wireless Sensor Network Modelling Based on Complex Networks

    OpenAIRE

    Xiao, Lin; Wu, Fahui; Yang, Dingcheng; Zhang, Tiankui; Zhu, Xiaoya

    2016-01-01

    The power consumption and energy efficiency of wireless sensor network are the significant problems in Internet of Things network. In this paper, we consider the network topology optimization based on complex network theory to solve the energy efficiency problem of WSN. We propose the energy efficient model of WSN according to the basic principle of small world from complex networks. Small world network has clustering features that are similar to that of the rules of the network but also has ...

  20. Analysis of renewable energy sources and electric vehicle penetration into energy systems predominantly based on lignite

    Science.gov (United States)

    Dedinec, A.; Jovanovski, B.; Gajduk, A.; Markovska, N.; Kocarev, L.

    2016-05-01

    We consider an integration of renewable energy into transport and electricity sectors through vehicle to grid (V2G) technologies for an energy system that is predominantly based on lignite. The national energy system of Macedonia is modeled using EnergyPLAN which integrates energy for electricity, transport and heat, and includes hourly fluctuations in human needs and the environment. We show that electric-vehicles can provide the necessary storage enabling a fully renewable energy profile for Macedonia that can match the country's growing demand for energy. Furthermore, a large penetration of electric vehicles leads to a dramatic reduction of 47% of small particles and other air pollutants generated by car traffic in 2050.

  1. Design and optimization of zero-energy-consumption based solar energy residential building systems

    Science.gov (United States)

    Zheng, D. L.; Yu, L. J.; Tan, H. W.

    2017-11-01

    Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

  2. Hydrogen-based electrochemical energy storage

    Science.gov (United States)

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  3. Ionic liquids based on phosphonium cations as neat lubricants or lubricant additives for a steel/steel contact.

    Science.gov (United States)

    Otero, Inés; López, Enriqueta R; Reichelt, Manuela; Villanueva, María; Salgado, Josefa; Fernández, Josefa

    2014-08-13

    After doing several miscibility essays with eight ionic liquids (ILs) and four base oils, the ILs tri(butyl)ethylphosphonium diethylphosphate [P4,4,4,2][C2C2PO4] and trihexyl(tetradecyl)phosphonium tris(pentafluoroethyl)trifluorophosphate [P6,6,6,14][(C2F5)3PF3] were selected to be studied as lubricant additives. The neat IL [P4,4,4,2][C2C2PO4], the base oils, and several blends were characterized in terms of density, viscosity, and thermal stability. The tribological performance of the miscible base oil/IL blends (1 wt %) and the neat [P4,4,4,2][C2C2PO4] were evaluated for the lubrication of an AISI 420 steel-100Cr6 steel contact pair. The friction coefficients and wear volumes obtained are also compared with those corresponding to the pure base oils and their mixtures with conventional additive zinc dialkyldithiophosphate (ZDDP). As neat lubricants, [P4,4,4,2][C2C2PO4] showed the best antifriction ability, whereas in terms of wear, better results were obtained with [P6,6,6,14][(C2F5)3PF3]. However, higher improvements in both friction and wear were found for blends containing [P4,4,4,2][C2C2PO4]. XPS analyses of the worn surfaces lubricated with these mixtures indicated the presence of phosphorus in the tribofilm formed on the wear track. However, this compound was slightly detected on tribosamples lubricated with blends containing [P6,6,6,14][(C2F5)3PF3].

  4. Contact-induced doping in aluminum-contacted molybdenum disulfide

    Science.gov (United States)

    Shimazu, Yoshihiro; Arai, Kensuke; Iwabuchi, Tatsuya

    2018-01-01

    The interface between two-dimensional semiconductors and metal contacts is an important topic of research of nanoelectronic devices based on two-dimensional semiconducting materials such as molybdenum disulfide (MoS2). We report transport properties of thin MoS2 flakes in a field-effect transistor geometry with Ti/Au and Al contacts. In contrast to widely used Ti/Au contacts, the conductance of flakes with Al contacts exhibits a smaller gate-voltage dependence, which is consistent with a substantial electron doping effect of the Al contacts. The temperature dependence of two-terminal conductance for the Al contacts is also considerably smaller than for the Ti/Au contacts, in which thermionic emission and thermally assisted tunneling play a dominant role. This result is explained in terms of the assumption that the carrier injection mechanism at an Al contact is dominated by tunneling that is not thermally activated.

  5. Energy saving behaviours: Development of a practice-based model

    International Nuclear Information System (INIS)

    Sweeney, Jillian C.; Kresling, Johannes; Webb, Dave; Soutar, Geoffrey N.; Mazzarol, Tim

    2013-01-01

    Financial pressure and concern for the environment has meant many consumers are aware of the need to reduce their consumption of many resources, including energy, which is the focus of the present study. While potential energy use deterrents in the form of access constraints and price increases are forms of extrinsic control, it is not clear how effective these are at reducing consumption and, indeed, it is not clear if such measures are consistent with people's underlying energy saving motivations. Beyond behavioural motivations, people's desires to reduce energy can be thwarted (barriers) and/or supported by a variety of factors, some within their control, while others are perhaps less so. Using a practice-based framework and a qualitative focus group approach, this study presents an exploratory study of these issues. Policy suggestions for overcoming barriers, as well suggestions as to how energy saving behaviours can be supported are offered. - Highlights: • We obtained consumers views about energy saving motivations, barriers and support. • Attitudes towards energy saving are not sufficient to change behaviours. • A practice-based approach to understanding energy saving behaviours is applied. • A practice-based energy-cultures framework (PBECF) is developed. • Barriers and support factors are identified that can be conceptualised within a PBECF

  6. Web-based treatment program using intensive therapeutic contact for patients with eating disorders: before-after study.

    Science.gov (United States)

    ter Huurne, Elke D; Postel, Marloes G; de Haan, Hein A; Drossaert, Constance H C; DeJong, Cor A J

    2013-02-04

    Although eating disorders are common in the Netherlands, only a few patients are treated by mental health care professionals. To reach and treat more patients with eating disorders, Tactus Addiction Treatment developed a web-based treatment program with asynchronous and intensive personalized communication between the patient and the therapist. This pilot study evaluated the web-based treatment program using intensive therapeutic contact in a population of 165 patients with an eating disorder. In a pre-post design with 6-week and 6-month follow-ups, eating disorder psychopathology, body dissatisfaction, Body Mass Index, physical and mental health, and quality of life were measured. The participant's satisfaction with the web-based treatment program was also studied. Attrition data were collected, and participants were classified as noncompleters if they did not complete all 10 assignments of the web-based treatment program. Differences in baseline characteristics between completers and noncompleters were studied, as well as reasons for noncompletion. Furthermore, differences in treatment effectiveness, treatment adherence, and baseline characteristics between participants of the three major eating disorder diagnostic groups EDNOS (n=115), BN purging (n=24), and BN nonpurging (n=24) were measured. Of the 165 participants who started the web-based treatment program, 89 participants (54%) completed all of the program assignments (completers) and 76 participants (46%) ended the program prematurely (noncompleters). Severe body dissatisfaction and physical and mental health problems seemed to have a negative impact on the completion of the web-based treatment program. Among the participants who completed the treatment program, significant improvements were found in eating disorder psychopathology (F=54.6, df = 68, Pphysical and mental health also significantly improved, and almost all of these positive effects were sustained up to 6 months after the participants had

  7. Energy Resiliency for Marine Corps Logistics Base Production Plant Barstow

    Science.gov (United States)

    2014-12-01

    13 1. Biomass, Landfill Gas, and Biogas ...security. Figure 3. SCE SAIDI and SIAIF data 2008 – 2014 E. ENERGY SOURCES 1. Biomass, Landfill Gas, and Biogas Biomass and Biogas ...availability is significant to this study because biogas is used at other Marine Corps Logistics Bases as a means of producing energy, and as an alternative to

  8. Energy demand forecasting method based on international statistical data

    International Nuclear Information System (INIS)

    Glanc, Z.; Kerner, A.

    1997-01-01

    Poland is in a transition phase from a centrally planned to a market economy; data collected under former economic conditions do not reflect a market economy. Final energy demand forecasts are based on the assumption that the economic transformation in Poland will gradually lead the Polish economy, technologies and modes of energy use, to the same conditions as mature market economy countries. The starting point has a significant influence on the future energy demand and supply structure: final energy consumption per capita in 1992 was almost half the average of OECD countries; energy intensity, based on Purchasing Power Parities (PPP) and referred to GDP, is more than 3 times higher in Poland. A method of final energy demand forecasting based on regression analysis is described in this paper. The input data are: output of macroeconomic and population growth forecast; time series 1970-1992 of OECD countries concerning both macroeconomic characteristics and energy consumption; and energy balance of Poland for the base year of the forecast horizon. (author). 1 ref., 19 figs, 4 tabs

  9. PMBLDCG based stand-alone wind energy conversion system for ...

    African Journals Online (AJOL)

    This paper deals with a permanent magnet brushless DC generator (PMBLDCG) based stand-alone wind energy conversion system (WECS) for small scale power generation. A buck-boost DC-DC converter is used for controlling the PMBLDCG speed to achieve optimum energy output from the wind turbine without sensing ...

  10. Energy enhancer for mask based laser materials processing

    DEFF Research Database (Denmark)

    Bastue, Jens; Olsen, Flemmming Ove

    1996-01-01

    A device capable of drastically improving the energy efficiency of present mask based laser materials processing systems is presented. Good accordance between experiments and simulations for a TEA-CO2 laser system designed for laser marking has been demonstrated. The energy efficiency may...... be improved with a factor of 2 - 4 for typical mask transmittances between 10 - 40%....

  11. Comparison of gas dehydration methods based on energy ...

    African Journals Online (AJOL)

    Comparison of gas dehydration methods based on energy consumption. ... This study compares three conventional methods of natural gas (Associated Natural Gas) dehydration to carry out the dehydration process and suitability of use on the basis of energy requirement. These methods are Triethylene Glycol (TEG) ...

  12. Optimization-Based Management of Energy Systems

    Science.gov (United States)

    2011-05-11

    collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE MAY 2011 2. REPORT TYPE 3. DATES COVERED 00-00...microgrid control provides an average annual 5-20% cost reduction compared with simple rule-based control strategy Annual Operating Cost Comparison NC...Generator Solar PV Battery G T IL I V Rs   STC STC STCMPPT MPPT TTk G P GP  1ˆ , E(SOC) RB ID IC 0 1 2 3 4 5 0 10 20 30 40 50 60 DC generator

  13. Energy Optimal Control Strategy of PHEV Based on PMP Algorithm

    Directory of Open Access Journals (Sweden)

    Tiezhou Wu

    2017-01-01

    Full Text Available Under the global voice of “energy saving” and the current boom in the development of energy storage technology at home and abroad, energy optimal control of the whole hybrid electric vehicle power system, as one of the core technologies of electric vehicles, is bound to become a hot target of “clean energy” vehicle development and research. This paper considers the constraints to the performance of energy storage system in Parallel Hybrid Electric Vehicle (PHEV, from which lithium-ion battery frequently charges/discharges, PHEV largely consumes energy of fuel, and their are difficulty in energy recovery and other issues in a single cycle; the research uses lithium-ion battery combined with super-capacitor (SC, which is hybrid energy storage system (Li-SC HESS, working together with internal combustion engine (ICE to drive PHEV. Combined with PSO-PI controller and Li-SC HESS internal power limited management approach, the research proposes the PHEV energy optimal control strategy. It is based on revised Pontryagin’s minimum principle (PMP algorithm, which establishes the PHEV vehicle simulation model through ADVISOR software and verifies the effectiveness and feasibility. Finally, the results show that the energy optimization control strategy can improve the instantaneity of tracking PHEV minimum fuel consumption track, implement energy saving, and prolong the life of lithium-ion batteries and thereby can improve hybrid energy storage system performance.

  14. GAS-FOVEAL CONTACT

    DEFF Research Database (Denmark)

    Alberti, Mark; la Cour, Morten

    2018-01-01

    PURPOSE: To compare gas-foveal contact in face-down positioning (FDP) and nonsupine positioning (NSP), to analyze causes of gas-foveal separation and to determine how gas-foveal contact affects clinical outcome after idiopathic macular hole repair. METHODS: Single center, randomized controlled...... study. Participants with an idiopathic macular hole were allocated to either FDP or NSP. Primary outcome was gas-foveal contact, calculated by analyzing positioning in relation to intraocular gas fill. Positioning was measured with an electronic device recording positioning for 72 hours postoperatively....... RESULTS: Positioning data were available for 33/35 in the FDP group and 35/37 in the NSP group, thus results are based on 68 analyzed participants. Median gas-foveal contact was 99.82% (range 73.6-100.0) in the FDP group and 99.57% (range 85.3-100.0) in the NSP group (P = 0.22). In a statistical model...

  15. Energy-Based Devices in Treatment of Acne Vulgaris.

    Science.gov (United States)

    Handler, Marc Z; Bloom, Bradley S; Goldberg, David J

    2016-05-01

    Acne vulgaris is a chronic dermatologic complaint with a multifactorial cause. Traditionally, antibiotics and retinoids have been used to manage the condition; patient compliance has been an ongoing issue. A variety of energy-based devices have been reported to be effective in the treatment of acne vulgaris. To review and summarize the current literature specific to treatment of acne vulgaris with energy-based devices. A review of the current literature of energy-based devices used for the treatment of acne vulgaris. Although limited randomized controlled trials for the treatment of acne have been performed, significant clinical improvement of acne vulgaris, especially of inflammatory lesions, has been demonstrated with a variety of energy-based devices. Newer approaches may lead to even better results.

  16. Polymer Based Nanocomposites for Solar Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Shaheen, S.; Olson, D.; White, M.; Mitchell, W.; Miedaner, A.; Curtis, C.; Rumbles, G.; Gregg, B.; Ginley, D.

    2005-01-01

    Organic semiconductor-based photovoltaic devices offer the promise of low cost photovoltaic technology that can be manufactured via large-scale, roll-to-roll printing techniques. Existing organic photovoltaic devices are currently limited to solar power conversion efficiencies of 3?5%. This is because of poor overlap between the absorption spectrum of the organic chromophores and the solar spectrum, non-ideal band alignment between the donor and acceptor species, and low charge carrier mobilities. To address these issues, we are investigating the development of dendrimeric organic semiconductors that are readily synthesized with high purity. They also benefit from optoelectronic properties, such as band gap and band positions, which can be easily tuned by substituting different chemical groups into the molecule. Additionally, we are developing nanostructured oxide/conjugated polymer composite photovoltaics. These composites take advantage of the high electron mobilities attainable in oxide semiconductors and can be fabricated using low-temperature solution-based growth techniques. Here, we discuss the synthesis and preliminary device results of these novel materials and composites.

  17. A renewables-based South African energy system?

    CSIR Research Space (South Africa)

    Bischof-Niemz, T

    2015-12-01

    Full Text Available Bischof-Niemz Chief Engineer A Renewables-based South African Energy System? Presentation at the Science Forum South Africa Dr Tobias Bischof-Niemz, CSIR Energy Centre Manager Johannesburg, 8 December 2015 Cell: +27 83 403 1108 Email: TBischof...Niemz@csir.co.za 2Dr Tobias Bischof-Niemz Head of CSIR’s Energy Centre Professional Experience • Member of the Ministerial Advisory Council on Energy (MACE) • Extraordinary Associate Professor at Stellenbosch University • Jul 2014 – today: Centre Manager at the CSIR...

  18. Energy conservation technologies based on thermodynamic principles

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Masaru [Shibaura Institute of Technology of Technology, Tokyo (Japan)

    1996-12-31

    In order to reduce CO{sub 2} emission to prevent global warming, the most promising way for electric generation in the Northeast Asia is to introduce cogeneration and {open_quotes}repowering{close_quotes} technologies based on high temperature gas turbines fueled by natural gas. Especially the old type coal burning boiler-steam turbine plants should be retrofit by introducing gas turbines to become highly efficient combined cycle. Same technologies should be applied to the old garbage incineration plants and/or even to the nuclear power plants. The exhaust heat or steam should become much increased and it should be utilized as the process heat for industries or heat supply as the distinct heating or cooling for residential area. This paper introduces a brief survey of these new technologies.

  19. Load-Sharing Characteristics of Power-Split Transmission System Based on Deformation Compatibility and Loaded Tooth Contact Analysis

    Directory of Open Access Journals (Sweden)

    Hao Dong

    2015-01-01

    Full Text Available In order to implement the uniform load distribution of the power-split transmission system, a pseudostatic model is built. Based on the loaded tooth contact analysis (LTCA technique, the actual meshing process of each gear pair is simulated and the fitting curve of time-varying mesh stiffness is obtained. And then, the torsional angle deformation compatibility conditions are proposed according to the closed-loop characteristic of power flow, which will be combined with the torque equilibrium conditions and elastic support conditions to calculate the transfer torque of each gear pair. Finally, the load-sharing coefficient of the power-split transmission system is obtained, and the influences of the installation errors are analyzed. The results show that the above-mentioned installation errors comprehensively influence the load-sharing characteristics, and the reduction of only one error could not effectively achieve perfect load-sharing characteristics. Allowing for the spline clearance floating and constrained by the radial spacing ring, the influence of the floating pinion is analyzed. It shows that the floating pinion can improve the load-sharing characteristics. Through the comparison between the theoretical and related experimental data, the reasonability and feasibility of the above-proposed method and model are verified.

  20. Physical-mechanical image of the cell surface on the base of AFM data in contact mode

    Science.gov (United States)

    Starodubtseva, M. N.; Starodubtsev, I. E.; Yegorenkov, N. I.; Kuzhel, N. S.; Konstantinova, E. E.; Chizhik, S. A.

    2017-10-01

    Physical and mechanical properties of the cell surface are well-known markers of a cell state. The complex of the parameters characterizing the cell surface properties, such as the elastic modulus (E), the parameters of adhesive (Fa), and friction (Ff) forces can be measured using atomic force microscope (AFM) in a contact mode and form namely the physical-mechanical image of the cell surface that is a fundamental element of the cell mechanical phenotype. The paper aims at forming the physical-mechanical images of the surface of two types of glutaraldehyde-fixed cancerous cells (human epithelial cells of larynx carcinoma, HEp-2c cells, and breast adenocarcinoma, MCF-7 cells) based on the data obtained by AFM in air and revealing the basic difference between them. The average values of friction, elastic and adhesive forces, and the roughness of lateral force maps, as well as dependence of the fractal dimension of lateral force maps on Z-scale factor have been studied. We have revealed that the response of microscale areas of the HEp-2c cell surface having numerous microvilli to external mechanical forces is less expressed and more homogeneous in comparison with the response of MCF-7 cell surface.

  1. Material identification based upon energy-dependent attenuation of neutrons

    Science.gov (United States)

    Marleau, Peter

    2015-10-06

    Various technologies pertaining to identifying a material in a sample and imaging the sample are described herein. The material is identified by computing energy-dependent attenuation of neutrons that is caused by presence of the sample in travel paths of the neutrons. A mono-energetic neutron generator emits the neutron, which is downscattered in energy by a first detector unit. The neutron exits the first detector unit and is detected by a second detector unit subsequent to passing through the sample. Energy-dependent attenuation of neutrons passing through the sample is computed based upon a computed energy of the neutron, wherein such energy can be computed based upon 1) known positions of the neutron generator, the first detector unit, and the second detector unit; or 2) computed time of flight of neutrons between the first detector unit and the second detector unit.

  2. Energy Management for Community Energy Network with CHP Based on Cooperative Game

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liu

    2018-04-01

    Full Text Available Integrated energy system (IES has received increasing attention in micro grid due to the high energy efficiency and low emission of carbon dioxide. Based on the technology of combined heat and power (CHP, this paper develops a novel operation mechanism with community micro turbine and shared energy storage system (ESS for energy management of prosumers. In the proposed framework, micro-grid operator (MGO equipped with micro turbine and ESS provides energy selling business and ESS leasing business for prosumers. Prosumers can make energy trading with public grid and MGO, and ESS will be shared among prosumers when they pay for the rent to MGO. Based on such framework, we adopt a cooperative game for prosumers to determine optimal energy trading strategies from MGO and public grid for the next day. Concretely, a cooperative game model is formulated to search the optimal strategies aiming at minimizing the daily cost of coalition, and then a bilateral Shapley value (BSV is proposed to solve the allocation problem of coalition’s cost among prosumers. To verify the effectiveness of proposed energy management framework, a practical example is conducted with a community energy network containing MGO and 10 residential buildings. Simulation results show that the proposed scheme is able to provide financial benefits to all prosumers, while providing peak load leveling for the grid.

  3. Research on Battery Energy Storage System Based on User Side

    Science.gov (United States)

    Wang, Qian; Zhang, Yichi; Yun, Zejian; Wang, Xuguang; Zhang, Dong; Bian, Di

    2018-01-01

    This paper introduces the effect of user side energy storage on the user side and the network side, a battery energy storage system for the user side is designed. The main circuit topology of the battery energy storage system based on the user side is given, the structure is mainly composed of two parts: DC-DC two-way half bridge converter and DC-AC two-way converter, a control strategy combining battery charging and discharging characteristics is proposed to decouple the grid side and the energy storage side, and the block diagram of the charging and discharging control of the energy storage system is given. The simulation results show that the battery energy storage system of the user side can not only realize reactive power compensation of low-voltage distribution network, but also improve the power quality of the users.

  4. Energy use in the rural areas of India: setting up a rural energy data base

    International Nuclear Information System (INIS)

    Sinha, Chandra Shekhar; Sinha, Shirish; Joshi, Veena

    1998-01-01

    Aggregating and forecasting demand are crucial parts of energy planning. While a large number of energy consumption surveys have been conducted in the past in the rural energy sector of India, the lack of sufficient data and its compilation, coupled with doubt about the quality of data, has made the task extremely difficult. This paper summarizes recent efforts to compile, computerize and analyze data from 638 village energy consumption surveys covering over 39,000 households, carried out by different organisations between 1985 and 1989. The details of the level of information provided in the survey reports, area of survey, land use pattern, asset ownership, etc., of the collated studies are presented. Results based on the analysis of the energy consumption data compiled are then discussed. The paper also compares the estimates with those based on other surveys in India. (author)

  5. Map of decentralised energy potential based on renewable energy sources in Croatia

    International Nuclear Information System (INIS)

    Schneider, D. R.; Ban, M.; Duic, N.; Bogdan, Z.

    2005-01-01

    Although the Republic of Croatia is almost completely electrified there are still regions where electricity network is not in place or network capacity is insufficient. These regions usually include areas of special state care (underdeveloped, war-affected or depopulated areas), islands, and mountainous areas. However, they often have good renewable energy potential. Decentralised energy generation based on renewable energy sources (wind power, hydropower, solar energy, biomass) has potential to ensure energy supply to users in remote and often isolated rural areas (off-grid applications). Such applications will primarily be related to tourism business in mountainous, rural and island/coastal regions. Also, agriculture, wood-processing and food-processing industries will potentially be interested in application of decentralised energy generation systems, most likely those using biomass as fuel (for example cogeneration facilities, connected on-grid).(author)

  6. An Energy Efficiency Evaluation Method Based on Energy Baseline for Chemical Industry

    Directory of Open Access Journals (Sweden)

    Dong-mei Yao

    2016-01-01

    Full Text Available According to the requirements and structure of ISO 50001 energy management system, this study proposes an energy efficiency evaluation method based on energy baseline for chemical industry. Using this method, the energy plan implementation effect in the processes of chemical production can be evaluated quantitatively, and evidences for system fault diagnosis can be provided. This method establishes the energy baseline models which can meet the demand of the different kinds of production processes and gives the general solving method of each kind of model according to the production data. Then the energy plan implementation effect can be evaluated and also whether the system is running normally can be determined through the baseline model. Finally, this method is used on cracked gas compressor unit of ethylene plant in some petrochemical enterprise; it can be proven that this method is correct and practical.

  7. Energy Harvesting Based Body Area Networks for Smart Health.

    Science.gov (United States)

    Hao, Yixue; Peng, Limei; Lu, Huimin; Hassan, Mohammad Mehedi; Alamri, Atif

    2017-07-10

    Body area networks (BANs) are configured with a great number of ultra-low power consumption wearable devices, which constantly monitor physiological signals of the human body and thus realize intelligent monitoring. However, the collection and transfer of human body signals consume energy, and considering the comfort demand of wearable devices, both the size and the capacity of a wearable device's battery are limited. Thus, minimizing the energy consumption of wearable devices and optimizing the BAN energy efficiency is still a challenging problem. Therefore, in this paper, we propose an energy harvesting-based BAN for smart health and discuss an optimal resource allocation scheme to improve BAN energy efficiency. Specifically, firstly, considering energy harvesting in a BAN and the time limits of human body signal transfer, we formulate the energy efficiency optimization problem of time division for wireless energy transfer and wireless information transfer. Secondly, we convert the optimization problem into a convex optimization problem under a linear constraint and propose a closed-form solution to the problem. Finally, simulation results proved that when the size of data acquired by the wearable devices is small, the proportion of energy consumed by the circuit and signal acquisition of the wearable devices is big, and when the size of data acquired by the wearable devices is big, the energy consumed by the signal transfer of the wearable device is decisive.

  8. Energy Harvesting Based Body Area Networks for Smart Health

    Directory of Open Access Journals (Sweden)

    Yixue Hao

    2017-07-01

    Full Text Available Body area networks (BANs are configured with a great number of ultra-low power consumption wearable devices, which constantly monitor physiological signals of the human body and thus realize intelligent monitoring. However, the collection and transfer of human body signals consume energy, and considering the comfort demand of wearable devices, both the size and the capacity of a wearable device’s battery are limited. Thus, minimizing the energy consumption of wearable devices and optimizing the BAN energy efficiency is still a challenging problem. Therefore, in this paper, we propose an energy harvesting-based BAN for smart health and discuss an optimal resource allocation scheme to improve BAN energy efficiency. Specifically, firstly, considering energy harvesting in a BAN and the time limits of human body signal transfer, we formulate the energy efficiency optimization problem of time division for wireless energy transfer and wireless information transfer. Secondly, we convert the optimization problem into a convex optimization problem under a linear constraint and propose a closed-form solution to the problem. Finally, simulation results proved that when the size of data acquired by the wearable devices is small, the proportion of energy consumed by the circuit and signal acquisition of the wearable devices is big, and when the size of data acquired by the wearable devices is big, the energy consumed by the signal transfer of the wearable device is decisive.

  9. Energy and mass-analyzer based on two plane capacitors

    International Nuclear Information System (INIS)

    Zashkvara, V.V.; Shestakov, V.P.; AN Kazakhskoj SSR, Alma-Ata. Inst. Yadernoj Fiziki)

    1983-01-01

    An energy and mass-analyzer of charged particle beams consisting of two plane capacitors has been calculated. Energy analysis is performed in the statistical regime, mass analysis - in the regime of time of flight measurement. Focusing in the time-of-flight is performed both according to an angle of beam divergence and to energy. Different modes of energy and mass analyzer operation were considered. In the first mode the energy analysis of a charged particle beam escaping a linearly extended source is accomplished and the energy distribution function N(W) is measured. In the second mode energy analysis and time-of-flight mass analysis of the charged particle beam are performed which permits to measure the spectral distribution function N(W, m) both in masses and energy. In the third mode the time-of-flight mass analysis of the beam is accomplished which enables to measure integral with respect to energy distribution function N(m) in masses. So, the simple device based on two plane capacitors can considerably improve the possibilities of the energy and mass analysis of charged particle beams emitted with linearly extended sources

  10. Assessing of energy policies based on Turkish agriculture:

    International Nuclear Information System (INIS)

    Sayin, Cengiz; Nisa Mencet, M.; Ozkan, Burhan

    2005-01-01

    In this study, the current energy status of Turkey and the effects of national energy policies on Turkish agricultural support policies are discussed for both current and future requirements. Turkey is an energy-importing country producing 30 mtoe (million tons of oil equivalent) energy but consuming 80 mtoe. The energy import ratio of Turkey is 65-70% and the majority of this import is based on petroleum and natural gas. Furthermore, while world energy demand increases by 1.8% annually, Turkey's energy demand increases by about 8%. Although energy consumption in agriculture is much lower than the other sectors in Turkey, energy use as both input and output of agricultural sector is a very important issue due to its large agricultural potential and rural area. Total agricultural land area is 27.8 million hectares and about 66.5% of this area is devoted for cereal production. On the other hand, Turkey has over 4 million agricultural farm holdings of which 70-75% is engaged in cereal production. Machinery expenses, mainly diesel, constitute 30-50% of total variable expenses in cereal production costs. It is observed that energy policies pursued in agriculture have been directly affected by diesel prices in Turkey. Therefore, support policy tools for using diesel and electricity in agriculture are being pursued by the Turkish government

  11. DEM code-based modeling of energy accumulation and release in structurally heterogeneous rock masses

    Science.gov (United States)

    Lavrikov, S. V.; Revuzhenko, A. F.

    2015-10-01

    Based on discrete element method, the authors model loading of a physical specimen to describe its capacity to accumulate and release elastic energy. The specimen is modeled as a packing of particles with viscoelastic coupling and friction. The external elastic boundary of the packing is represented by particles connected by elastic springs. The latter means introduction of an additional special potential of interaction between the boundary particles, that exercises effect even when there is no direct contact between the particles. On the whole, the model specimen represents an element of a medium capable of accumulation of deformation energy in the form of internal stresses. The data of the numerical modeling of the physical specimen compression and the laboratory testing results show good qualitative consistency.

  12. Energy-based control for a biologically inspired hexapod robot with rolling locomotion

    Directory of Open Access Journals (Sweden)

    Takuma Nemoto

    2015-04-01

    Full Text Available This paper presents an approach to control rolling locomotion on the level ground with a biologically inspired hexapod robot. For controlling rolling locomotion, a controller which can compensate energy loss with rolling locomotion of the hexapod robot is designed based on its dynamic model. The dynamic model describes the rolling locomotion which is limited to planar one by an assumption that the hexapod robot does not fall down while rolling and influences due to collision and contact with the ground, and it is applied for computing the mechanical energy of the hexapod robot and a plant for a numerical simulation. The numerical simulation of the rolling locomotion on the level ground verifies the effectiveness of the proposed controller. The simulation results show that the hexapod robot can perform the rolling locomotion with the proposed controller. In conclusion, it is shown that the proposed control approach is effective in achieving the rolling locomotion on the level ground.

  13. Harvesting energy: Place and local entrepreneurship in community-based renewable energy transition

    International Nuclear Information System (INIS)

    Süsser, Diana; Döring, Martin; Ratter, Beate M.W.

    2017-01-01

    Transition towards a renewable energy supply initiates a physical (re)shaping of places and a social transformation of communities into renewable energy communities. Although socio-cultural challenges of energy transition have been recognised (), understandings about socio-geographic places of energy transition and their underlying social processes and structures are insufficiently studied and often remain underestimated. To close this gap, we theoretically and empirically analysed the multifaceted interplay between place, local entrepreneurship and ‘community renewable energy’. Our study is based on an analysis of regional documents and policy reports, and on qualitative interviews undertaken with inhabitants in the case-study municipality of Reußenköge (Germany). Our findings reveal two important aspects: Firstly, people's individual and shared place meanings which materialised in social, physical, historical and climate-related place-attachments and meanings of contested and innovative place are important ingredients bearing an impact on processes of adopting or rejecting renewables. Secondly, differentiated characteristics of entrepreneurs, namely grounded, collaborative, innovative, change-making, economic, communicating, networking and political aspects, appeared to be relevant for the acceptance and support in community-based renewable energy projects. Our findings reveal that energy policies, funding schemes and administrative structures should recognise local socio-geographic important elements in the context of a sustained and decentralised energy transition. - Highlights: • Places are resources of experiences, creativity and innovation for community renewables. • Energy policies should recognise place-based approaches to grassroots community energy actions. • A located view of multifaceted entrepreneurship is relevant to support community renewable energy. • Supportive funding schemes should empower community-based concepts.

  14. Cu(In,Ga)Se2Solar Cells with Amorphous In2O3-Based Front Contact Layers.

    Science.gov (United States)

    Koida, Takashi; Ueno, Yuko; Nishinaga, Jiro; Higuchi, Hirohumi; Takahashi, Hideki; Iioka, Masayuki; Shibata, Hajime; Niki, Shigeru

    2017-09-06

    Amorphous (a-) In 2 O 3 -based front contact layers composed of transparent conducting oxide (TCO) and transparent oxide semiconductor (TOS) layers were proved to be effective in enhancing the short-circuit current density (J sc ) of Cu(In,Ga)Se 2 (CIGS) solar cells with a glass/Mo/CIGS/CdS/TOS/TCO structure, while maintaining high fill factor (FF) and open-circuit voltage (V oc ). An n-type a-In-Ga-Zn-O layer was introduced between the CdS and TCO layers. Unlike unintentionally doped ZnO broadly used as TOS layers in CIGS solar cells, the grain-boundary(GB)-free amorphous structure of the a-In-Ga-Zn-O layers allowed high electron mobility with superior control over the carrier density (N). High FF and V oc values were achieved in solar cells containing a-In-Ga-Zn-O layers with N values broadly ranging from 2 × 10 15 to 3 × 10 18 cm -3 . The decrease in FF and V oc produced by the electronic inhomogeneity of solar cells was mitigated by controlling the series resistance within the TOS layer of CIGS solar cells. In addition, a-In 2 O 3 :H and a-In-Zn-O layers exhibited higher electron mobilities than the ZnO:Al layers conventionally used as TCO layers in CIGS solar cells. The In 2 O 3 -based layers exhibited lower free carrier absorption while maintaining similar sheet resistance than ZnO:Al. The TCO and TOS materials and their combinations did not significantly change the V oc of the CIGS solar cells and the mini-modules.

  15. Optimal contact definition for reconstruction of Contact Maps

    Directory of Open Access Journals (Sweden)

    Stehr Henning

    2010-05-01

    Full Text Available Abstract Background Contact maps have been extensively used as a simplified representation of protein structures. They capture most important features of a protein's fold, being preferred by a number of researchers for the description and study of protein structures. Inspired by the model's simplicity many groups have dedicated a considerable amount of effort towards contact prediction as a proxy for protein structure prediction. However a contact map's biological interest is subject to the availability of reliable methods for the 3-dimensional reconstruction of the structure. Results We use an implementation of the well-known distance geometry protocol to build realistic protein 3-dimensional models from contact maps, performing an extensive exploration of many of the parameters involved in the reconstruction process. We try to address the questions: a to what accuracy does a contact map represent its corresponding 3D structure, b what is the best contact map representation with regard to reconstructability and c what is the effect of partial or inaccurate contact information on the 3D structure recovery. Our results suggest that contact maps derived from the application of a distance cutoff of 9 to 11Å around the Cβ atoms constitute the most accurate representation of the 3D structure. The reconstruction process does not provide a single solution to the problem but rather an ensemble of conformations that are within 2Å RMSD of the crystal structure and with lower values for the pairwise average ensemble RMSD. Interestingly it is still possible to recover a structure with partial contact information, although wrong contacts can lead to dramatic loss in reconstruction fidelity. Conclusions Thus contact maps represent a valid approximation to the structures with an accuracy comparable to that of experimental methods. The optimal contact definitions constitute key guidelines for methods based on contact maps such as structure prediction through

  16. Clean Cities Program Contacts (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-03-01

    This fact sheet provides contact information for program staff of the U.S. Department of Energy's Clean Cities program, as well as contact information for the nearly 100 local Clean Cities coalitions across the country.

  17. Muon radiography and deformation analysis of the lava dome formed by the 1944 eruption of Usu, Hokkaido —Contact between high-energy physics and volcano physics—

    Science.gov (United States)

    TANAKA, Hiroyuki K. M.; YOKOYAMA, Izumi

    2008-01-01

    Lava domes are one of the conspicuous topographic features on volcanoes. The subsurface structure of the lava dome is important to discuss its formation mechanism. In the 1944 eruption of Volcano Usu, Hokkaido, a new lava dome was formed at its eastern foot. After the completion of the lava dome, various geophysical methods were applied to the dome to study its subsurface structure, but resulted in a rather ambiguous conclusion. Recently, from the results of the levelings, which were repeated during the eruption, “pseudo growth curves” of the lava dome were obtained. The curves suggest that the lava dome has a bulbous shape. In the present work, muon radiography, which previously proved effective in imaging the internal structure of Volcano Asama, has been applied to the Usu lava dome. The muon radiography measures the distribution of the “density length” of volcanic bodies when detectors are arranged properly. The result obtained is consistent with the model deduced from the pseudo growth curves. The measurement appears to afford useful method to clarify the subsurface structure of volcanoes and its temporal changes, and in its turn to discuss volcanic processes. This is a point of contact between high-energy physics and volcano physics. PMID:18941290

  18. Simulation-based optimization of sustainable national energy systems

    International Nuclear Information System (INIS)

    Batas Bjelić, Ilija; Rajaković, Nikola

    2015-01-01

    The goals of the EU2030 energy policy should be achieved cost-effectively by employing the optimal mix of supply and demand side technical measures, including energy efficiency, renewable energy and structural measures. In this paper, the achievement of these goals is modeled by introducing an innovative method of soft-linking of EnergyPLAN with the generic optimization program (GenOpt). This soft-link enables simulation-based optimization, guided with the chosen optimization algorithm, rather than manual adjustments of the decision vectors. In order to obtain EnergyPLAN simulations within the optimization loop of GenOpt, the decision vectors should be chosen and explained in GenOpt for scenarios created in EnergyPLAN. The result of the optimization loop is an optimal national energy master plan (as a case study, energy policy in Serbia was taken), followed with sensitivity analysis of the exogenous assumptions and with focus on the contribution of the smart electricity grid to the achievement of EU2030 goals. It is shown that the increase in the policy-induced total costs of less than 3% is not significant. This general method could be further improved and used worldwide in the optimal planning of sustainable national energy systems. - Highlights: • Innovative method of soft-linking of EnergyPLAN with GenOpt has been introduced. • Optimal national energy master plan has been developed (the case study for Serbia). • Sensitivity analysis on the exogenous world energy and emission price development outlook. • Focus on the contribution of smart energy systems to the EU2030 goals. • Innovative soft-linking methodology could be further improved and used worldwide.

  19. Prediction Based Energy Balancing Forwarding in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Yang Jian-Jun

    2017-01-01

    Full Text Available In the recent cellular network technologies, relay stations extend cell coverage and enhance signal strength for mobile users. However, busy traffic makes the relay stations in hot area run out of energy quickly. Energy is a very important factor in the forwarding of cellular network since mobile users(cell phones in hot cells often suffer from low throughput due to energy lack problems. In many situations, the energy lack problems take place because the energy loading is not balanced. In this paper, we present a prediction based forwarding algorithm to let a mobile node dynamically select the next relay station with highest potential energy capacity to resume communication. Key to this strategy is that a relay station only maintains three past status, and then it is able to predict the potential energy capacity. Then, the node selects the next hop with potential maximal energy. Moreover, a location based algorithm is developed to let the mobile node figure out the target region in order to avoid flooding. Simulations demonstrate that our approach significantly increase the aggregate throughput and decrease the delay in cellular network environment.

  20. Energy Management in Smart Cities Based on Internet of Things: Peak Demand Reduction and Energy Savings.

    Science.gov (United States)

    Mahapatra, Chinmaya; Moharana, Akshaya Kumar; Leung, Victor C M

    2017-12-05

    Around the globe, innovation with integrating information and communication technologies (ICT) with physical infrastructure is a top priority for governments in pursuing smart, green living to improve energy efficiency, protect the environment, improve the quality of life, and bolster economy competitiveness. Cities today faces multifarious challenges, among which energy efficiency of homes and residential dwellings is a key requirement. Achieving it successfully with the help of intelligent sensors and contextual systems would help build smart cities of the future. In a Smart home environment Home Energy Management plays a critical role in finding a suitable and reliable solution to curtail the peak demand and achieve energy conservation. In this paper, a new method named as Home Energy Management as a Service (HEMaaS) is proposed which is based on neural network based Q -learning algorithm. Although several attempts have been made in the past to address similar problems, the models developed do not cater to maximize the user convenience and robustness of the system. In this paper, authors have proposed an advanced Neural Fitted Q -learning method which is self-learning and adaptive. The proposed method provides an agile, flexible and energy efficient decision making system for home energy management. A typical Canadian residential dwelling model has been used in this paper to test the proposed method. Based on analysis, it was found that the proposed method offers a fast and viable solution to reduce the demand and conserve energy during peak period. It also helps reducing the carbon footprint of residential dwellings. Once adopted, city blocks with significant residential dwellings can significantly reduce the total energy consumption by reducing or shifting their energy demand during peak period. This would definitely help local power distribution companies to optimize their resources and keep the tariff low due to curtailment of peak demand.

  1. Energy Management in Smart Cities Based on Internet of Things: Peak Demand Reduction and Energy Savings

    Directory of Open Access Journals (Sweden)

    Chinmaya Mahapatra

    2017-12-01

    Full Text Available Around the globe, innovation with integrating information and communication technologies (ICT with physical infrastructure is a top priority for governments in pursuing smart, green living to improve energy efficiency, protect the environment, improve the quality of life, and bolster economy competitiveness. Cities today faces multifarious challenges, among which energy efficiency of homes and residential dwellings is a key requirement. Achieving it successfully with the help of intelligent sensors and contextual systems would help build smart cities of the future. In a Smart home environment Home Energy Management plays a critical role in finding a suitable and reliable solution to curtail the peak demand and achieve energy conservation. In this paper, a new method named as Home Energy Management as a Service (HEMaaS is proposed which is based on neural network based Q-learning algorithm. Although several attempts have been made in the past to address similar problems, the models developed do not cater to maximize the user convenience and robustness of the system. In this paper, authors have proposed an advanced Neural Fitted Q-learning method which is self-learning and adaptive. The proposed method provides an agile, flexible and energy efficient decision making system for home energy management. A typical Canadian residential dwelling model has been used in this paper to test the proposed method. Based on analysis, it was found that the proposed method offers a fast and viable solution to reduce the demand and conserve energy during peak period. It also helps reducing the carbon footprint of residential dwellings. Once adopted, city blocks with significant residential dwellings can significantly reduce the total energy consumption by reducing or shifting their energy demand during peak period. This would definitely help local power distribution companies to optimize their resources and keep the tariff low due to curtailment of peak demand.

  2. Energy Cooperation in Ultradense Network Powered by Renewable Energy Based on Cluster and Learning Strategy

    Directory of Open Access Journals (Sweden)

    Chunhong Duo

    2017-01-01

    Full Text Available A new method about renewable energy cooperation among small base stations (SBSs is proposed, which is for maximizing the energy efficiency in ultradense network (UDN. In UDN each SBS is equipped with energy harvesting (EH unit, and the energy arrival times are modeled as a Poisson counting process. Firstly, SBSs of large traffic demands are selected as the clustering centers, and then all SBSs are clustered using dynamic k-means algorithm. Secondly, SBSs coordinate their renewable energy within each formed cluster. The process of energy cooperation among SBSs is considered as Markov decision process. Q-learning algorithm is utilized to optimize energy cooperation. In the algorithm there are four different actions and their corresponding reward functions. Q-learning explores the action as much as possible and predicts better action by calculating reward. In addition, ε greedy policy is used to ensure the algorithm convergence. Finally, simulation results show that the new method reduces data dimension and improves calculation speed, which furthermore improves the utilization of renewable energy and promotes the performance of UDN. Through online optimization, the proposed method can significantly improve the energy utilization rate and data transmission rate.

  3. Lumping of degree-based mean-field and pair-approximation equations for multistate contact processes

    Science.gov (United States)

    Kyriakopoulos, Charalampos; Grossmann, Gerrit; Wolf, Verena; Bortolussi, Luca

    2018-01-01

    Contact processes form a large and highly interesting class of dynamic processes on networks, including epidemic and information-spreading networks. While devising stochastic models of such processes is relatively easy, analyzing them is very challenging from a computational point of view, particularly for large networks appearing in real applications. One strategy to reduce the complexity of their analysis is to rely on approximations, often in terms of a set of differential equations capturing the evolution of a random node, distinguishing nodes with different topological contexts (i.e., different degrees of different neighborhoods), such as degree-based mean-field (DBMF), approximate-master-equation (AME), or pair-approximation (PA) approaches. The number of differential equations so obtained is typically proportional to the maximum degree kmax of the network, which is much smaller than the size of the master equation of the underlying stochastic model, yet numerically solving these equations can still be problematic for large kmax. In this paper, we consider AME and PA, extended to cope with multiple local states, and we provide an aggregation procedure that clusters together nodes having similar degrees, treating those in the same cluster as indistinguishable, thus reducing the number of equations while preserving an accurate description of global observables of interest. We also provide an automatic way to build such equations and to identify a small number of degree clusters that give accurate results. The method is tested on several case studies, where it shows a high level of compression and a reduction of computational time of several orders of magnitude for large networks, with minimal loss in accuracy.

  4. Market Mechanism Design for Renewable Energy based on Risk Theory

    Science.gov (United States)

    Yang, Wu; Bo, Wang; Jichun, Liu; Wenjiao, Zai; Pingliang, Zeng; Haobo, Shi

    2018-02-01

    Generation trading between renewable energy and thermal power is an efficient market means for transforming supply structure of electric power into sustainable development pattern. But the trading is hampered by the output fluctuations of renewable energy and the cost differences between renewable energy and thermal power at present. In this paper, the external environmental cost (EEC) is defined and the EEC is introduced into the generation cost. At same time, the incentive functions of renewable energy and low-emission thermal power are designed, which are decreasing functions of EEC. On these bases, for the market risks caused by the random variability of EEC, the decision-making model of generation trading between renewable energy and thermal power is constructed according to the risk theory. The feasibility and effectiveness of the proposed model are verified by simulation results.

  5. A New Hybrid Bathroom System Based on Energy Saving Concept

    Directory of Open Access Journals (Sweden)

    Cui Bo-wen

    2016-01-01

    Full Text Available Based on the characteristics of hot water supply in bathroom, this article proposes a new hybrid energy hot water supply system. The programmable logic controller(PLC as the master controller was adopted in this system, which could automatically detect and storage main thermal physical of the system, such as temperature, water level, solar radiation intensity, power consumption and so on. The active thermal utilization technology of solar energy, air-source heat pump technology, solar energy intensive natural ventilation technology and low temperature hot water floor radiant heating technology were organically integrated in this system, which has the advantages of energy conservation and environment protection, high automation, safe and reliable operation, etc. At the same time, it can make good use of electric power cost between on-peak and off-peak, and promote the optimal allocation of power resources and reduce the cost, which can achieve the goal of intelligent control and energy saving.

  6. Concomitant contact allergy to the resins, reactive diluents and hardener of a bisphenol A/F-based epoxy resin in subway construction workers.

    Science.gov (United States)

    Chu, Chia-Yu; Pontén, Ann; Sun, Chee-Ching; Jee, Shiou-Hwa

    2006-03-01

    An outbreak of suspected contact dermatitis among subway construction workers was suspected to be due to a new bisphenol A/F-based epoxy resin system (ERS). The construction workers used ERSs during the insertion of iron bars into concrete walls. The objective of the study was to determine the components (if any) of the ERS responsible for the contact allergy. Patch testing was performed on 20 of the 22 construction workers who had had contact with the ERS, and to the various subcomponents of component A on 5 of the 7 who reacted to this component. 9 patients (9/22, 40.9%) had clinical symptoms and signs of suspected contact dermatitis at presentation. 7 of these 9, but none of the 11 asymptomatic individuals, were positive to component A, while all were negative to component B. Of the 5 cases receiving further patch testing, all reacted to m-xylylene diamine, 4 to 1,6-hexanediol diglycidyl ether, 3 to epoxy resins of the bisphenol F-type and trimethylolpropane triglycidyl ether 0.25% petrolatum, and only 1 to epoxy resins of the bisphenol A-type. Contact allergy to ERSs may involve hardeners and diluents as well as resins, and patch testing for reaction to all components should be performed.

  7. Community Based Approach to Wind Energy Information Dissemination

    Energy Technology Data Exchange (ETDEWEB)

    Innis, S.

    2003-09-26

    The purpose of the Department of Energy's grant was to transfer to New Mexico and Utah a national award-winning market-based strategy to aggregate demand for wind energy. Their experiences over the past few years in New Mexico and utah have been quite different. In both states they have developed stronger relationships with utilities and policymakers which will increase the effectiveness of the future advocacy efforts.

  8. European Climate - Energy Security Nexus. A model based scenario analysis

    International Nuclear Information System (INIS)

    Criqui, Patrick; Mima, Silvana

    2011-01-01

    In this research, we have provided an overview of the climate-security nexus in the European sector through a model based scenario analysis with POLES model. The analysis underline that under stringent climate policies, Europe take advantage of a double dividend in its capacity to develop a new cleaner energy model and in lower vulnerability to potential shocks on the international energy markets. (authors)

  9. Energy Data Base: Subject categories and scope: A reference manual

    International Nuclear Information System (INIS)

    Grissom, M.C.

    1987-04-01

    The subject scope of the Energy Data Base (EDB) is defined, encompassing all technological aspects of energy production, conversion, and efficient utilization, and the economic, social, and political aspects as well. Coverage also includes the basic sciences as applicable. The subject areas within the scope of EDB are defined and hierarchically numbered, and scope notes are provided to define the extent of interest in certain areas, particularly areas of basic research

  10. European Climate - Energy Security Nexus. A model based scenario analysis

    Energy Technology Data Exchange (ETDEWEB)

    Criqui, Patrick; Mima, Silvana

    2011-01-15

    In this research, we have provided an overview of the climate-security nexus in the European sector through a model based scenario analysis with POLES model. The analysis underline that under stringent climate policies, Europe take advantage of a double dividend in its capacity to develop a new cleaner energy model and in lower vulnerability to potential shocks on the international energy markets. (authors)

  11. Numerical investigation of metal-semiconductor-insulator-semiconductor passivated hole contacts based on atomic layer deposited AlO x

    Science.gov (United States)

    Ke, Cangming; Xin, Zheng; Ling, Zhi Peng; Aberle, Armin G.; Stangl, Rolf

    2017-08-01

    Excellent c-Si tunnel layer surface passivation has been obtained recently in our lab, using atomic layer deposited aluminium oxide (ALD AlO x ) in the tunnel layer regime of 0.9 to 1.5 nm, investigated to be applied for contact passivation. Using the correspondingly measured interface properties, this paper compares the theoretical collection efficiency of a conventional metal-semiconductor (MS) contact on diffused p+ Si to a metal-semiconductor-insulator-semiconductor (MSIS) contact on diffused p+ Si or on undoped n-type c-Si. The influences of (1) the tunnel layer passivation quality at the tunnel oxide interface (Q f and D it), (2) the tunnel layer thickness and the electron and hole tunnelling mass, (3) the tunnel oxide material, and (4) the semiconductor capping layer material properties are investigated numerically by evaluation of solar cell efficiency, open-circuit voltage, and fill factor.

  12. Autonomous Magneto-Cumulative Energy Source Based on Permanent Magnets

    Science.gov (United States)

    Gurin, V. E.; Boriskin, A. S.; Vlasov, Yu. V.; Golosov, S. N.; Dimant, E. M.; Demidov, V. A.; Kazakov, S. A.; Kazakova, N. R.; Klimashov, M. V.; Korolev, P. V.; Kutumov, S. V.; Pikar, A. S.; Romanov, A. P.; Shapovalov, E. V.; Shibitov, Yu. M.; Shchetnikov, E. I.; Yanenko, V. A.

    2006-08-01

    In the paper we describe a design of autonomous source of electromagnetic energy with initial field, created by permanent barium oxide magnets and present results of its tests. The energy source consists of magnetic system with initial energy of 1 J, helical magneto-cumulative generator with helix diameter of 50 mm, amplifying the field energy in 130 times, and transforming unit for a load matching. At peak power on helical generator of 66 MW, the voltage of 16 kV was obtained at inductive load of 40 μH. Weight of the energy autonomous source is 5 kg, HE-charge mass is 100 g. Several variants of magnetic systems were tested. Comparison of the magneto-cumulative generator operation, powered from permanent magnets and powered from capacitor bank was carried out. Optimizing the magnetic system with numerical methods the authors managed to get almost identical distribution of the fields in the generators. Finally, the generator based on permanent magnets operates and provides similar output characteristics as the generator powered from the capacitor bank. In contrast to other magneto-cumulative energy sources powered, for example, from an accumulator or piezo-generator, this source, based on permanent magnets, has higher specific energy characteristics, does not require any switching elements and always ready for operation.

  13. Microinstallations Based on Renewable Energy Sources in the Construction Sector

    Science.gov (United States)

    Kurzak, Lucjan

    2017-10-01

    The focus of this paper is on the status and prognoses of the use of microinstallations based on renewable energy sources to supply heat and power. The technologies that have been important in Europe and Poland for microgeneration of electricity include photovoltaic systems, micro wind turbines and co-generation systems. Solar collectors, heat pumps and biomass have also been used to generate heat. Microinstallations for renewable energy sources represent the initial point and the foundation for the development of micro networks, intelligent networks and the whole prosumer energy sector.

  14. Entirely renewable energy-based electricity supply system (small scale)

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi, A. [Monash Univ., Caulfield (Australia). Div. of Electrical and Computer Systems Engineering

    1997-12-31

    This paper presents a system comprising of a renewable source of energy and an energy storage device to smooth the power fluctuations. In order to investigate the performance of the system, an exact mathematical model for the system has been developed. Because of non-linearity of the mathematical model a computational method is used for performance investigation of the system. The objective of the paper is to present an entirely renewable energy based electricity supply system (small scale), to suggest the mathematical model of the system and computational method to analyze the performance of the system.

  15. Energy flexibility assessment of a multi agent-based smart home energy system

    OpenAIRE

    Amin Shokri Gazafroudi; Tiago Pinto; Francisco Prieto-Castrillo; Juan Manuel Corchado; Omid Abrishambaf; Aria Jozi; Zita Vale

    2018-01-01

    Power systems worldwide are complex and challenging environments. The increasing necessity for an adequate integration of renewable energy sources is resulting in a rising complexity in power systems operation. Multi-agent based simulation platforms have proven to be a good option to study the several issues related to these systems. In a smaller scale, a home energy management system would be effective for the both sides of the network. It can reduce the electricity costs of the demand side,...

  16. Acoustic Focusing and Energy Confinement Based on Multilateral Metasurfaces

    Science.gov (United States)

    Qi, Shuibao; Li, Yong; Assouar, Badreddine

    2017-05-01

    Metamaterial-based acoustic wave manipulation shows great potential in effective acoustic energy confinement and low-frequency acoustic isolation. We numerically and theoretically propose here a concept based on multilateral metasurfaces for reflected acoustic focusing and energy confinement. The theoretical phase-shift profile required for reflected wave focusing and governed by the generalized Snell's law can be discretely realized by appropriately arraying the labyrinthine units in the right sequences. Based on this design, multilateral metasurfaces for acoustic wave focusing and energy confinement under point-source incidence are considered and sufficiently investigated. The coupling effects and multiple reflections between or among metasurfaces, which play a significant role in the energy confinement, are initially analyzed and discussed. We show that the acoustic focusing and confinement increase with the sides of the multilateral metasurfaces as anticipated. In addition to the contribution of the first reflection, multiple reflections also contribute to the acoustic focusing and energy confinement, especially when the metasurfaces are configured in parallel. The proposed multilateral metasurfaces should have excellent performance in acoustic energy confinement in various situations due to the variable designs and strong acoustic focusing capabilities.

  17. Writable electrochemical energy source based on graphene oxide

    Science.gov (United States)

    Wei, Di

    2015-10-01

    Graphene oxide (GO) was mainly used as raw material for various types of reduced graphene oxide (rGO) as a cost effective method to make graphene like materials. However, applications of its own unique properties such as extraordinary proton conductivity and super-permeability to water were overlooked. Here GO based battery-like planar energy source was demonstrated on arbitrary insulating substrate (e.g. polymer sheet/paper) by coating PEDOT, GO ink and rGO on Ag charge collectors. Energy from such GO battery depends on its length and one unit cell with length of 0.5 cm can generate energy capacity of 30 Ah/L with voltage up to 0.7 V when room temperature ionic liquid (RTIL) is added. With power density up to 0.4 W/cm3 and energy density of 4 Wh/L, GO battery was demonstrated to drive an electrochromic device. This work is the first attempt to generate decent energy using the fast transported water molecules inside GO. It provides very safe energy source that enables new applications otherwise traditional battery technology can not make including building a foldable energy source on paper and platform for futuristic wearable electronics. A disposable energy source made of GO was also written on a plastic glove to demonstrate wearability.

  18. Agent-based modelling of consumer energy choices

    Science.gov (United States)

    Rai, Varun; Henry, Adam Douglas

    2016-06-01

    Strategies to mitigate global climate change should be grounded in a rigorous understanding of energy systems, particularly the factors that drive energy demand. Agent-based modelling (ABM) is a powerful tool for representing the complexities of energy demand, such as social interactions and spatial constraints. Unlike other approaches for modelling energy demand, ABM is not limited to studying perfectly rational agents or to abstracting micro details into system-level equations. Instead, ABM provides the ability to represent behaviours of energy consumers -- such as individual households -- using a range of theories, and to examine how the interaction of heterogeneous agents at the micro-level produces macro outcomes of importance to the global climate, such as the adoption of low-carbon behaviours and technologies over space and time. We provide an overview of ABM work in the area of consumer energy choices, with a focus on identifying specific ways in which ABM can improve understanding of both fundamental scientific and applied aspects of the demand side of energy to aid the design of better policies and programmes. Future research needs for improving the practice of ABM to better understand energy demand are also discussed.

  19. Resonant wave energy harvester based on dielectric elastomer generator

    Science.gov (United States)

    Moretti, Giacomo; Pietro Rosati Papini, Gastone; Righi, Michele; Forehand, David; Ingram, David; Vertechy, Rocco; Fontana, Marco

    2018-03-01

    Dielectric elastomer generators (DEGs) are a class of capacitive solid-state devices that employ highly stretchable dielectrics and conductors to convert mechanical energy into high-voltage direct-current electricity. Their promising performance in terms of convertible energy and power density has been mostly proven in quasi-static experimental tests with prescribed deformation. However, the assessment of their ability in harvesting energy from a dynamic oscillating source of mechanical energy is crucial to demonstrate their effectiveness in practical applications. This paper reports a first demonstration of a DEG system that is able to convert the oscillating energy carried by water waves into electricity. A DEG prototype is built using a commercial polyacrylate film (VHB 4905 by 3M) and an experimental campaign is conducted in a wave-flume facility, i.e. an artificial basin that makes it possible to generate programmed small-scale waves at different frequencies and amplitudes. In resonant conditions, the designed system demonstrates the delivery of a maximum of 0.87 W of electrical power output and 0.64 J energy generated per cycle, with corresponding densities per unit mass of dielectric elastomer of 197 W kg-1 and 145 J kg-1. Additionally, a notable maximum fraction of 18% of the input wave energy is converted into electricity. The presented results provide a promising demonstration of the operation and effectiveness of ocean wave energy converters based on elastic capacitive generators.

  20. Fabrication and characterization of a sandpaper-based flexible energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Shieh, Jen-Yu; Wu, Cheng-Hung; Tsai, Sung-Ying [Institute of Electro-Optical and Materials Science, National Formosa University, 64 Wenhua Road, Huwei, Yunlin 63208, Taiwan (China); Yu, Hsin Her, E-mail: hhyu@nfu.edu.tw [Department of Biotechnology, National Formosa University, 64 Wenhua Road, Huwei, Yunlin 63208, Taiwan (China)

    2016-02-28

    Graphical abstract: A sandpaper-based supercapacitor was assembled from two graphene/CNTs-coated fine-sandpaper electrodes and a PVA porous separator enclosed with H{sub 3}PO{sub 4}/PVA gel electrolyte, then packaged between two PET sheets by hot pressing. The galvanostatic charge/discharge curves obtained at a current of 0.10 mA over about 3000 cycles. The capacitance retention rates remained over 91% after this period, indicating the electrochemical stability of the supercapacitor. Thus, the supercapacitor based on the fine sandpaper electrode has a long lifetime and good cycling stability. - Highlights: • Carbon nanotubes prevent stacking of graphene sheets and act as spacers and binders. • The sandpaper surface provides more electrode/electrolyte contact area. • The gel electrolyte can prevent contact discontinuity in a supercapacitor. • Sandpaper-based supercapacitors exhibit excellent flexibility and cycling stability. - Abstract: In this paper, graphene and carbon nanotubes dispersed in a pectin solution are examined as a precursor for electrode fabrication for supercapacitor applications. The carbon nanotubes not only prevent the stacking of graphene sheets, but also act as spacers and binders. Dropping the hybrid conductive suspension onto sandpaper is found to form a sandpaper-based electrode that improves the specific capacitance of a subsequently fabricated supercapacitor because of its high surface area. In particular, the large contact surface of the sandpaper allows it to absorb more electrolyte ions and increases the number of ions assembled on the electrode surface. For the supercapacitor fabrication, replacing the liquid or solid electrolyte with a gel electrolyte prevents leakage and contact discontinuity. Therefore, a high-performance supercapacitor can be constructed with one separator coated with a gel electrolyte inserted between two fine-sandpaper-based electrodes, which can be assembled into a sandwich structure by hot pressing

  1. Energy based model for temperature dependent behavior of ferromagnetic materials

    International Nuclear Information System (INIS)

    Sah, Sanjay; Atulasimha, Jayasimha

    2017-01-01

    An energy based model for temperature dependent anhysteretic magnetization curves of ferromagnetic materials is proposed and benchmarked against experimental data. This is based on the calculation of macroscopic magnetic properties by performing an energy weighted average over all possible orientations of the magnetization vector. Most prior approaches that employ this method are unable to independently account for the effect of both inhomogeneity and temperature in performing the averaging necessary to model experimental data. Here we propose a way to account for both effects simultaneously and benchmark the model against experimental data from ~5 K to ~300 K for two different materials in both annealed (fewer inhomogeneities) and deformed (more inhomogeneities) samples. This demonstrates that this framework is well suited to simulate temperature dependent experimental magnetic behavior. - Highlights: • Energy based model for temperature dependent ferromagnetic behavior. • Simultaneously accounts for effect of temperature and inhomogeneities. • Benchmarked against experimental data from 5 K to 300 K.

  2. Graphene-Based Carbon Materials for Electrochemical Energy Storage

    Directory of Open Access Journals (Sweden)

    Fei Liu

    2013-01-01

    Full Text Available Because of their unique 2D structure and numerous fascinating properties, graphene-based materials have attracted particular attention for their potential applications in energy storage devices. In this review paper, we focus on the latest work regarding the development of electrode materials for batteries and supercapacitors from graphene and graphene-based carbon materials. To begin, the advantages of graphene as an electrode material and the existing problems facing its use in this application will be discussed. The next several sections deal with three different methods for improving the energy storage performance of graphene: the restacking of the nanosheets, the doping of graphene with other elements, and the creation of defects on graphene planes. State-of-the-art work is reviewed. Finally, the prospects and further developments in the field of graphene-based materials for electrochemical energy storage are discussed.

  3. Energy-based coordinated control of wind energy conversion system with DFIG

    Science.gov (United States)

    Qu, Y. B.; Song, H. H.

    2011-12-01

    This article presents an energy-based coordinated control of machine- and grid-side converters in a wind energy conversion system (WECS) with a doubly-fed induction generator (DFIG) based on the theory of port-controlled Hamiltonian (PCH) system. Taking into account energy transmission in the dual PWM converter rather than treating rectification and inversion as separate parts, an integrated PCH model for the whole WECS was established from physical meanings. And depending on the new model, an energy-based coordinated control approach was proposed to meet the control requirements of the WECS with an additional objective which was to limit the DC-link voltage fluctuation. The approach was applied on a 2MW WECS, and compared with the energy-based respective control strategy using MATLAB/Simulink. The results show that the proposed control approach provides faster dynamic performance since the two converters operate with the knowledge of each other's operating status, and thus is able to smooth the power flow in the DC-link more effectively.

  4. Innovative energy absorbing devices based on composite tubes

    Science.gov (United States)

    Tiwari, Chandrashekhar

    Analytical and experimental study of innovative load limiting and energy absorbing devices are presented here. The devices are based on composite tubes and can be categorized in to two groups based upon the energy absorbing mechanisms exhibited by them, namely: foam crushing and foam fracturing. The device based on foam crushing as the energy absorbing mechanism is composed of light weight elastic-plastic foam filling inside an angle ply composite tube. The tube is tailored to have a high Poisson’s ratio (>20). Upon being loaded the device experiences large transverse contraction resulting in rapid decrease in diameter. At a certain axial load the foam core begins to crush and energy is dissipated. This device is termed as crush tube device. The device based upon foam shear fracture as the energy absorbing mechanism involves an elastic-plastic core foam in annulus of two concentric extension-twist coupled composite tubes with opposite angles of fibers. The core foam is bonded to the inner and outer tube walls. Upon being loaded axially, the tubes twist in opposite directions and fracture the core foam in out of plane shear and thus dissipate the energy stored. The device is termed as sandwich core device (SCD). The devices exhibit variations in force-displacement characteristics with changes in design and material parameters, resulting in wide range of energy absorption capabilities. A flexible matrix composite system was selected, which was composed of high stiffness carbon fibers as reinforcements in relatively low stiffness polyurethane matrix, based upon large strain to failure capabilities and large beneficial elastic couplings. Linear and non-linear analytical models were developed encapsulating large deformation theory of the laminated composite shells (using non-linear strain energy formulation) to the fracture mechanics of core foam and elastic-plastic deformation theory of the foam filling. The non-linear model is capable of including material and

  5. MEMS-based thick film PZT vibrational energy harvester

    DEFF Research Database (Denmark)

    Lei, Anders; Xu, Ruichao; Thyssen, Anders

    2011-01-01

    We present a MEMS-based unimorph silicon/PZT thick film vibrational energy harvester with an integrated proof mass. We have developed a process that allows fabrication of high performance silicon based energy harvesters with a yield higher than 90%. The process comprises a KOH etch using...... a mechanical front side protection of an SOI wafer with screen printed PZT thick film. The fabricated harvester device produces 14.0 μW with an optimal resistive load of 100 kΩ from 1g (g=9.81 m s-2) input acceleration at its resonant frequency of 235 Hz....

  6. Energy-based ferromagnetic material model with magnetic anisotropy

    International Nuclear Information System (INIS)

    Steentjes, Simon; Henrotte, François; Hameyer, Kay

    2017-01-01

    Non-oriented soft magnetic materials are commonly assumed to be magnetically isotropic. However, due to the rolling process a preferred direction exists along the rolling direction. This uniaxial magnetic anisotropy, and the related magnetostriction effect, are critical to the accurate calculation of iron losses and magnetic forces in rotating electrical machines. This paper proposes an extension of an isotropic energy-based vector hysteresis model to account for these two effects. - Highlights: • Energy-based vector hysteresis model with magnetic anisotropy. • Two-scale model to account for pinning field distribution. • Pinning force and reluctivity are extended to anisotropic case.

  7. Energy Efficient FPGA based Hardware Accelerators for Financial Applications

    DEFF Research Database (Denmark)

    Kenn Toft, Jakob; Nannarelli, Alberto

    2014-01-01

    Field Programmable Gate Arrays (FPGAs) based accelerators are very suitable to implement application-specific processors using uncommon operations or number systems. In this work, we design FPGA-based accelerators for two financial computations with different characteristics and we compare...... the accelerator performance and energy consumption to a software execution of the application. The experimental results show that significant speed-up and energy savings, can be obtained for large data sets by using the accelerator at expenses of a longer development time....

  8. Cooperative relay-based multicasting for energy and delay minimization

    KAUST Repository

    Atat, Rachad

    2012-08-01

    Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

  9. Energy-Based Metrics for Arthroscopic Skills Assessment

    Directory of Open Access Journals (Sweden)

    Behnaz Poursartip

    2017-08-01

    Full Text Available Minimally invasive skills assessment methods are essential in developing efficient surgical simulators and implementing consistent skills evaluation. Although numerous methods have been investigated in the literature, there is still a need to further improve the accuracy of surgical skills assessment. Energy expenditure can be an indication of motor skills proficiency. The goals of this study are to develop objective metrics based on energy expenditure, normalize these metrics, and investigate classifying trainees using these metrics. To this end, different forms of energy consisting of mechanical energy and work were considered and their values were divided by the related value of an ideal performance to develop normalized metrics. These metrics were used as inputs for various machine learning algorithms including support vector machines (SVM and neural networks (NNs for classification. The accuracy of the combination of the normalized energy-based metrics with these classifiers was evaluated through a leave-one-subject-out cross-validation. The proposed method was validated using 26 subjects at two experience levels (novices and experts in three arthroscopic tasks. The results showed that there are statistically significant differences between novices and experts for almost all of the normalized energy-based metrics. The accuracy of classification using SVM and NN methods was between 70% and 95% for the various tasks. The results show that the normalized energy-based metrics and their combination with SVM and NN classifiers are capable of providing accurate classification of trainees. The assessment method proposed in this study can enhance surgical training by providing appropriate feedback to trainees about their level of expertise and can be used in the evaluation of proficiency.

  10. On a solvability of hydro-mechanical problem based on contact problem with visco-plastic friction in Bingham rheology

    Czech Academy of Sciences Publication Activity Database

    Nedoma, Jiří; Tomášek, Luboš

    2008-01-01

    Roč. 218, č. 1 (2008), s. 116-124 ISSN 0377-0427 Institutional research plan: CEZ:AV0Z10300504 Keywords : visco-plasticity * Bingham rheology * contact problems with friction * variational inequalities * FEM * geomechanics * hydromechanics Subject RIV: BA - General Mathematics Impact factor: 1.048, year: 2008

  11. Ensemble EMD-based automatic extraction of the catenary structure wavelength from the pantograph-catenary contact corce

    NARCIS (Netherlands)

    Liu, Zhigang; Wang, H.; Dollevoet, R.P.B.J.; Yang, S.; Nunez Vicencio, Alfredo; Zhang, J.

    2016-01-01

    This paper explores the use of pantograph-catenary contact force (PCCF) for monitoring of the current collection quality and detection of anomalies in the interaction between pantograph and catenary. The concept of catenary structure wavelength (CSW) is proposed as the dominant component of PCCF. It

  12. Multicenter Patch Testing With a Resol Resin Based on Phenol and Formaldehyde Within the International Contact Dermatitis Research Group

    DEFF Research Database (Denmark)

    Isaksson, M.; Ale, I.; Andersen, Klaus Ejner

    2015-01-01

    .2%) reacted to PFR-2. Of those 28 individuals, one had a positive reaction to formaldehyde and 2 to p-tertiary-butylphenol-formaldehyde resin. Simultaneous allergic reactions were noted to colophonium in 3, to Myroxylon pereirae in 5, and to fragrance mix I in 8. Conclusions The contact allergy frequency...

  13. EDITORIAL: Close contact Close contact

    Science.gov (United States)

    Demming, Anna

    2010-07-01

    The development of scanning probe techniques, such as scanning tunnelling microscopy [1], has often been touted as the catalyst for the surge in activity and progress in nanoscale science and technology. Images of nanoscale structural detail have served as an invaluable investigative resource and continue to fascinate with the fantastical reality of an intricate nether world existing all around us, but hidden from view of the naked eye by a disparity in scale. As is so often the case, the invention of the scanning tunnelling microscope heralded far more than just a useful new apparatus, it demonstrated the scope for exploiting the subtleties of electronic contact. The shrinking of electronic devices has been a driving force for research into molecular electronics, in which an understanding of the nature of electronic contact at junctions is crucial. In response, the number of experimental techniques in molecular electronics has increased rapidly in recent years. Scanning tunnelling microscopes have been used to study electron transfer through molecular films on a conducting substrate, and the need to monitor the contact force of scanning tunnelling electrodes led to the use of atomic force microscopy probes coated in a conducting layer as studied by Cui and colleagues in Arizona [2]. In this issue a collaboration of researchers at Delft University and Leiden University in the Netherlands report a new device architecture for the independent mechanical and electrostatic tuning of nanoscale charge transport, which will enable thorough studies of molecular transport in the future [3]. Scanning probes can also be used to pattern surfaces, such as through spatially-localized Suzuki and Heck reactions in chemical scanning probe lithography. Mechanistic aspects of spatially confined Suzuki and Heck chemistry are also reported in this issue by researchers in Oxford [4]. All these developments in molecular electronics fabrication and characterization provide alternative

  14. Silicon-Rich Silicon Carbide Hole-Selective Rear Contacts for Crystalline-Silicon-Based Solar Cells.

    Science.gov (United States)

    Nogay, Gizem; Stuckelberger, Josua; Wyss, Philippe; Jeangros, Quentin; Allebé, Christophe; Niquille, Xavier; Debrot, Fabien; Despeisse, Matthieu; Haug, Franz-Josef; Löper, Philipp; Ballif, Christophe

    2016-12-28

    The use of passivating contacts compatible with typical homojunction thermal processes is one of the most promising approaches to realizing high-efficiency silicon solar cells. In this work, we investigate an alternative rear-passivating contact targeting facile implementation to industrial p-type solar cells. The contact structure consists of a chemically grown thin silicon oxide layer, which is capped with a boron-doped silicon-rich silicon carbide [SiC x (p)] layer and then annealed at 800-900 °C. Transmission electron microscopy reveals that the thin chemical oxide layer disappears upon thermal annealing up to 900 °C, leading to degraded surface passivation. We interpret this in terms of a chemical reaction between carbon atoms in the SiC x (p) layer and the adjacent chemical oxide layer. To prevent this reaction, an intrinsic silicon interlayer was introduced between the chemical oxide and the SiC x (p) layer. We show that this intrinsic silicon interlayer is beneficial for surface passivation. Optimized passivation is obtained with a 10-nm-thick intrinsic silicon interlayer, yielding an emitter saturation current density of 17 fA cm -2 on p-type wafers, which translates into an implied open-circuit voltage of 708 mV. The potential of the developed contact at the rear side is further investigated by realizing a proof-of-concept hybrid solar cell, featuring a heterojunction front-side contact made of intrinsic amorphous silicon and phosphorus-doped amorphous silicon. Even though the presented cells are limited by front-side reflection and front-side parasitic absorption, the obtained cell with a V oc of 694.7 mV, a FF of 79.1%, and an efficiency of 20.44% demonstrates the potential of the p + /p-wafer full-side-passivated rear-side scheme shown here.

  15. Distributed energy resources at naval base ventura county building 1512

    International Nuclear Information System (INIS)

    Bailey, Owen C.; Marnay, Chris

    2004-01-01

    This paper reports the findings of a preliminary assessment of the cost effectiveness of distributed energy resources at Naval Base Ventura County (NBVC) Building 1512. This study was conducted in response to the base's request for design assistance to the Federal Energy Management Program. Given the current tariff structure there are two main decisions facing NBVC: whether to install distributed energy resources (DER), or whether to continue the direct access energy supply contract. At the current effective rate, given assumptions about the performance and structure of building energy loads and available generating technology characteristics, the results of this study indicate that if the building installed a 600 kW DER system with absorption cooling and heat capabilities chosen by cost minimization, the energy cost savings would be about 14 percent, or $55,000 per year. However, under current conditions, this study also suggests that significant savings could be obtained if Building 1 512 changed from the direct access contract to a SCE TOU-8 (Southern California Edison time of use tariff number 8) rate without installing a DER system. At current SCE TOU-8 tariffs, the potential savings from installation of a DER system would be about 4 percent, or $15,000 per year

  16. Design optimization of PVDF-based piezoelectric energy harvesters

    Directory of Open Access Journals (Sweden)

    Jundong Song

    2017-09-01

    Full Text Available Energy harvesting is a promising technology that powers the electronic devices via scavenging the ambient energy. Piezoelectric energy harvesters have attracted considerable interest for their high conversion efficiency and easy fabrication in minimized sensors and transducers. To improve the output capability of energy harvesters, properties of piezoelectric materials is an influential factor, but the potential of the material is less likely to be fully exploited without an optimized configuration. In this paper, an optimization strategy for PVDF-based cantilever-type energy harvesters is proposed to achieve the highest output power density with the given frequency and acceleration of the vibration source. It is shown that the maximum power output density only depends on the maximum allowable stress of the beam and the working frequency of the device, and these two factors can be obtained by adjusting the geometry of piezoelectric layers. The strategy is validated by coupled finite-element-circuit simulation and a practical device. The fabricated device within a volume of 13.1 mm3 shows an output power of 112.8 μW which is comparable to that of the best-performing piezoceramic-based energy harvesters within the similar volume reported so far.

  17. An Internet of Energy Things Based on Wireless LPWAN

    Directory of Open Access Journals (Sweden)

    Yonghua Song

    2017-08-01

    Full Text Available Under intense environmental pressure, the global energy sector is promoting the integration of renewable energy into interconnected energy systems. The demand-side management (DSM of energy systems has drawn considerable industrial and academic attention in attempts to form new flexibilities to respond to variations in renewable energy inputs to the system. However, many DSM concepts are still in the experimental demonstration phase. One of the obstacles to DSM usage is that the current information infrastructure was mainly designed for centralized systems, and does not meet DSM requirements. To overcome this barrier, this paper proposes a novel information infrastructure named the Internet of Energy Things (IoET in order to make DSM practicable by basing it on the latest wireless communication technology: the low-power wide-area network (LPWAN. The primary advantage of LPWAN over general packet radio service (GPRS and area Internet of Things (IoT is its wide-area coverage, which comes with minimum power consumption and maintenance costs. Against this background, this paper briefly reviews the representative LPWAN technologies of narrow-band Internet of Things (NB-IoT and Long Range (LoRa technology, and compares them with GPRS and area IoT technology. Next, a wireless-to-cloud architecture is proposed for the IoET, based on the main technical features of LPWAN. Finally, this paper looks forward to the potential of IoET in various DSM application scenarios.

  18. Calculation of the yearly energy performance of heating systems based on the European Building Energy Directive and related CEN Standards

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.; de Carli, Michele

    2011-01-01

    According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting syst......–20% of the building energy demand. The additional loss depends on the type of heat emitter, type of control, pump and boiler. Keywords: Heating systems; CEN standards; Energy performance; Calculation methods......According to the Energy Performance of Buildings Directive (EPBD) all new European buildings (residential, commercial, industrial, etc.) must since 2006 have an energy declaration based on the calculated energy performance of the building, including heating, ventilating, cooling and lighting...

  19. A prospective evaluation of the symptom-based screening approach to the management of children who are contacts of tuberculosis cases.

    Science.gov (United States)

    Triasih, Rina; Robertson, Colin F; Duke, Trevor; Graham, Stephen M

    2015-01-01

    Child tuberculosis contact screening and management can enhance case finding and prevent tuberculosis disease. It is universally recommended but rarely implemented in tuberculosis-endemic settings. The World Health Organization (WHO)-recommended symptom-based screening approach could improve implementation but has not been prospectively evaluated. We conducted a cohort study of children who were close contacts of pulmonary tuberculosis patients in Indonesia from August 2010 to December 2012. We performed clinical assessment, tuberculin skin test, and chest radiography in all eligible children irrespective of symptoms at baseline. Mycobacterial culture and Xpert MTB/RIF assay were performed on sputum from children with persistent symptoms of suspected tuberculosis. Children were managed according to WHO guidelines and were prospectively followed for 12 months. A total of 269 child contacts of 140 index cases were evaluated. At baseline, 21 (8%) children had tuberculosis diagnosed clinically; an additional 102 (38%) had evidence of infection without disease. Of children with any tuberculosis-related symptoms at baseline, 21% had tuberculosis diagnosed compared with none of the asymptomatic children (P children who did not receive IPT. Symptom-based screening is an effective and simple approach to child tuberculosis contact management that can be implemented at the primary healthcare level. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Energy Aware Cluster Based Routing Scheme For Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Roy Sohini

    2015-09-01

    Full Text Available Wireless Sensor Network (WSN has emerged as an important supplement to the modern wireless communication systems due to its wide range of applications. The recent researches are facing the various challenges of the sensor network more gracefully. However, energy efficiency has still remained a matter of concern for the researches. Meeting the countless security needs, timely data delivery and taking a quick action, efficient route selection and multi-path routing etc. can only be achieved at the cost of energy. Hierarchical routing is more useful in this regard. The proposed algorithm Energy Aware Cluster Based Routing Scheme (EACBRS aims at conserving energy with the help of hierarchical routing by calculating the optimum number of cluster heads for the network, selecting energy-efficient route to the sink and by offering congestion control. Simulation results prove that EACBRS performs better than existing hierarchical routing algorithms like Distributed Energy-Efficient Clustering (DEEC algorithm for heterogeneous wireless sensor networks and Energy Efficient Heterogeneous Clustered scheme for Wireless Sensor Network (EEHC.

  1. Energy survey of the coal based sponge iron industry

    Directory of Open Access Journals (Sweden)

    Nishant R. Dey

    2015-09-01

    Full Text Available A survey is made on a typical coal based Indian sponge iron plant of capacity 500 t/d in order to identify the largest energy losses and find ways to increase the efficiency. The required data are obtained by measurements or taken from production industries. The process efficiency is about 51.31%. The energy balances of the process show that the gap between theoretical and actual energy consumption is 45.2% and the exhausts make up the largest loss of 43.5%. A huge amount of waste gas is generated during operation and substantial part of it associated with the waste gas, remains unutilized. The energy content in the exhaust gases which is found at useful temperature can be used in three different ways: by internal use; by external energy supply; or by power generation. The four possible potential areas are identified where energy is being lost and untapped. The largest improvements would be made by design modifications adopting a novel energy conservation scenario by process integration and thereby decreasing the coal and water consumption and by decreasing the cold fresh air.

  2. ALLERGIC CONTACT DERMATITIS

    Directory of Open Access Journals (Sweden)

    Trisna Yuliharti Tersinanda

    2013-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Allergic contact dermatitis is an immunologic reaction that tends to involve the surrounding skin and may even spread beyond affected sites. This skin disease is one of the more frequent, and costly dermatologic problems. Recent data from United Kingdom and United States suggest that the percentage of occupational contact dermatitis due to allergy may be much higher, thus raising the economic impact of occupational allergic contact dermatitis. There is not enough data about the epidemiology of allergic contact dermatitis in Indonesia, however based on research that include beautician in Denpasar, about 27,6 percent had side effect of cosmetics, which is 25,4 percent of it manifested as allergic contact dermatitis. Diagnosis of allergic contact dermatitis is based on anamnesis, physical examination, patch test, and this disease should be distinguished from other eczematous skin disease. The management is prevention of allergen exposure, symptomatic treatment, and physicochemical barrier /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  3. Estimation of Supercapacitor Energy Storage Based on Fractional Differential Equations

    Science.gov (United States)

    Kopka, Ryszard

    2017-12-01

    In this paper, new results on using only voltage measurements on supercapacitor terminals for estimation of accumulated energy are presented. For this purpose, a study based on application of fractional-order models of supercapacitor charging/discharging circuits is undertaken. Parameter estimates of the models are then used to assess the amount of the energy accumulated in supercapacitor. The obtained results are compared with energy determined experimentally by measuring voltage and current on supercapacitor terminals. All the tests are repeated for various input signal shapes and parameters. Very high consistency between estimated and experimental results fully confirm suitability of the proposed approach and thus applicability of the fractional calculus to modelling of supercapacitor energy storage.

  4. Estimation of Supercapacitor Energy Storage Based on Fractional Differential Equations.

    Science.gov (United States)

    Kopka, Ryszard

    2017-12-22

    In this paper, new results on using only voltage measurements on supercapacitor terminals for estimation of accumulated energy are presented. For this purpose, a study based on application of fractional-order models of supercapacitor charging/discharging circuits is undertaken. Parameter estimates of the models are then used to assess the amount of the energy accumulated in supercapacitor. The obtained results are compared with energy determined experimentally by measuring voltage and current on supercapacitor terminals. All the tests are repeated for various input signal shapes and parameters. Very high consistency between estimated and experimental results fully confirm suitability of the proposed approach and thus applicability of the fractional calculus to modelling of supercapacitor energy storage.

  5. FUZZY LOGIC BASED ENERGY EFFICIENT PROTOCOL IN WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    Zhan Wei Siew

    2012-12-01

    Full Text Available Wireless sensor networks (WSNs have been vastly developed due to the advances in microelectromechanical systems (MEMS using WSN to study and monitor the environments towards climates changes. In environmental monitoring, sensors are randomly deployed over the interest area to periodically sense the physical environments for a few months or even a year. Therefore, to prolong the network lifetime with limited battery capacity becomes a challenging issue. Low energy adaptive cluster hierarchical (LEACH is the common clustering protocol that aim to reduce the energy consumption by rotating the heavy workload cluster heads (CHs. The CHs election in LEACH is based on probability model which will lead to inefficient in energy consumption due to least desired CHs location in the network. In WSNs, the CHs location can directly influence the network energy consumption and further affect the network lifetime. In this paper, factors which will affect the network lifetime will be presented and the demonstration of fuzzy logic based CH selection conducted in base station (BS will also be carried out. To select suitable CHs that will prolong the network first node dies (FND round and consistent throughput to the BS, energy level and distance to the BS are selected as fuzzy inputs.

  6. Biomass-based energy carriers in the transportation sector

    International Nuclear Information System (INIS)

    Johansson, Bengt.

    1995-03-01

    The purpose of this report is to study the technical and economic prerequisites to attain reduced carbon dioxide emissions through the use of biomass-based energy carriers in the transportation sector, and to study other environmental impacts resulting from an increased use of biomass-based energy carriers. CO 2 emission reduction per unit arable and forest land used for biomass production (kg CO 2 /ha,year) and costs for CO 2 emission reduction (SEK/kg CO 2 ) are estimated for the substitution of gasoline and diesel with rape methyl ester, biogas from lucerne, ethanol from wheat and ethanol, methanol, hydrogen and electricity from Salix and logging residues. Of the studied energy carriers, those based on Salix provide the largest CO 2 emission reduction. In a medium long perspective, the costs for CO 2 emission reduction seem to be lowest for methanol from Salix and logging residues. The use of fuel cell vehicles, using methanol or hydrogen as energy carriers, can in a longer perspective provide more energy efficient utilization of biomass for transportation than the use of internal combustion engine vehicles. 136 refs, 12 figs, 25 tabs

  7. Composition and doping control for metal-organic chemical vapor deposition of InP-based double heterojunction bipolar transistor with hybrid base structure consisting of GaAsSb contact and InGaAsSb graded layers

    Science.gov (United States)

    Hoshi, Takuya; Kashio, Norihide; Sugiyama, Hiroki; Yokoyama, Haruki; Kurishima, Kenji; Ida, Minoru; Matsuzaki, Hideaki

    2017-07-01

    We report on a method for composition and doping control for metalorganic chemical vapor deposition of a double heterojunction bipolar transistor (DHBT) with a hybrid base structure consisting of a compositionally graded InGaAsSb for boosting an average electron velocity and a heavily doped thin GaAsSb for lowering the base contact resistivity. The GaAsSb contact layer can be formed by simply turning off the supply of In precursor tetramethylindium (TMIn) after the growth of the composition and doping graded InGaAsSb base. Consequently, the solid composition and hole concentration of hybrid base can be properly controlled by just modulating the supply of only TMIn and carbon tetrabromide. Secondary ion mass spectroscopy for the DHBT wafer reveals that the contents of In, Ga, and C inside the base are actually modulated from the collector side to the emitter side as expected. Transmission-line-model measurements were performed for the compositionally graded-InGaAsSb/GaAsSb hybrid base. The contact resistivity is estimated to be 5.3 Ω µm2, which is lower than half the value of a compositionally graded InGaAsSb base without the GaAsSb contact layer. The results indicate that the compositionally-graded-InGaAsSb/GaAsSb-contact hybrid base structure grown by this simple method is very advantageous for obtaining DHBTs with a very high maximum oscillation frequency.

  8. Group-based Motion Detection for Energy-Efficient Localisation

    Directory of Open Access Journals (Sweden)

    Alban Cotillon

    2012-10-01

    Full Text Available Long-term outdoor localization remains challenging due to the high energy profiles of GPS modules. Duty cycling the GPS module combined with inertial sensors can improve energy consumption. However, inertial sensors that are kept active all the time can also drain mobile node batteries. This paper proposes duty cycling strategies for inertial sensors to maintain a target position accuracy and node lifetime. We present a method for duty cycling motion sensors according to features of movement events, and evaluate its energy and accuracy profile for an empirical data trace of cattle movement. We further introduce the concept of group-based duty cycling, where nodes that cluster together can share the burden of motion detection to reduce their duty cycles. Our evaluation shows that both variants of motion sensor duty cycling yield up to 78% improvement in overall node power consumption, and that the group-based method yields an additional 20% power reduction during periods of low mobility.

  9. Geothermal energy in Idaho: site data base and development status

    Energy Technology Data Exchange (ETDEWEB)

    McClain, D.W.

    1979-07-01

    Detailed site specific data regarding the commercialization potential of the proven, potential, and inferred geothermal resource areas in Idaho are presented. To assess the potential for geothermal resource development in Idaho, several kinds of data were obtained. These include information regarding institutional procedures for geothermal development, logistical procedures for utilization, energy needs and forecasted demands, and resource data. Area reports, data sheets, and scenarios were prepared that described possible geothermal development at individual sites. In preparing development projections, the objective was to base them on actual market potential, forecasted growth, and known or inferred resource conditions. To the extent possible, power-on-line dates and energy utilization estimates are realistic projections of the first events. Commercialization projections were based on the assumption that an aggressive development program will prove sufficient known and inferred resources to accomplish the projected event. This report is an estimate of probable energy developable under an aggressive exploration program and is considered extremely conservative. (MHR)

  10. Graphene Paper Based Nanomaterials for Electrochemical Sensing and Energy Conversion

    DEFF Research Database (Denmark)

    Zhang, Minwei

    Graphene has emerged as a highly interesting material since it was experimentally isolated for the first timein 2004. This single-atom-thick nanosheet consisting of carbon atoms arrayed in a honeycomb pattern,displays outstanding physicochemical properties, including as an excellent conductor...... of heat and electricity,large specific surface area, and high mechanical strength. Therefore, graphene based materials are expected to have great potential for use in the fields of sensors, catalysis, and as electrode materials for energy storage and conversion. In order to link practical applications...... and energy technologies. This PhD project is devoted to the synthesis, characterization and applications of graphene paper based nanomaterials for electrochemical sensors and energy conversion. The thesis is divided into three parts with 8 chapters in total. In Chapter 1, we provide an overview...

  11. Polyaniline (PANi based electrode materials for energy storage and conversion

    Directory of Open Access Journals (Sweden)

    Huanhuan Wang

    2016-09-01

    Full Text Available Polyaniline (PANi as one kind of conducting polymers has been playing a great role in the energy storage and conversion devices besides carbonaceous materials and metallic compounds. Due to high specific capacitance, high flexibility and low cost, PANi has shown great potential in supercapacitor. It alone can be used in fabricating an electrode. However, the inferior stability of PANi limits its application. The combination of PANi and other active materials (carbon materials, metal compounds or other polymers can surpass these intrinsic disadvantages of PANi. This review summarizes the recent progress in PANi based composites for energy storage/conversion, like application in supercapacitors, rechargeable batteries, fuel cells and water hydrolysis. Besides, PANi derived nitrogen-doped carbon materials, which have been widely employed as carbon based electrodes/catalysts, are also involved in this review. PANi as a promising material for energy storage/conversion is deserved for intensive study and further development.

  12. CREATIV: Research-based innovation for industry energy efficiency

    International Nuclear Information System (INIS)

    Tangen, Grethe; Hemmingsen, Anne Karin T.; Neksa, Petter

    2011-01-01

    Improved energy efficiency is imperative to minimise the greenhouse gas emissions and to ensure future energy security. It is also a key to continued profitability in energy consuming industry. The project CREATIV is a research initiative for industry energy efficiency focusing on utilisation of surplus heat and efficient heating and cooling. In CREATIV, international research groups work together with key vendors of energy efficiency equipment and an industry consortium including the areas metallurgy, pulp and paper, food and fishery, and commercial refrigeration supermarkets. The ambition of CREATIV is to bring forward technology and solutions enabling Norway to reduce both energy consumption and greenhouse gas emissions by 25% within 2020. The main research topics are electricity production from low temperature heat sources in supercritical CO 2 cycles, energy efficient end-user technology for heating and cooling based on natural working fluids and system optimisation, and efficient utilisation of low temperature heat by developing new sorption systems and compact compressor-expander units. A defined innovation strategy in the project will ensure exploitation of research results and promote implementation in industry processes. CREATIV will contribute to the recruitment of competent personnel to industry and academia by educating PhD and post doc candidates and several MSc students. The paper presents the CREATIV project, discusses its scientific achievements so far, and outlines how the project results can contribute to reducing industry energy consumption. - Highlights: → New technology for improved energy efficiency relevant across several industries. → Surplus heat exploitation and efficient heating and cooling are important means. → Focus on power production from low temperature heat and heat pumping technologies. → Education and competence building are given priority. → The project consortium includes 20 international industry companies and

  13. Voltage Sag Source Location Based on Instantaneous Energy Detection

    DEFF Research Database (Denmark)

    Chen, Zhe; Kong, Wei; Dong, Xinzhou

    2008-01-01

    Voltage sag is a major power quality problem, which could disrupt the operation of voltage-sensitive equipment. This paper presents the method based on variation components-based instantaneous energy for voltage sag source detection. Simulations have been performed to provide the thorough analysis...... for system with distributed generation units. The studies show that the presented method can effectively detect the location of voltage sag source....

  14. Functional energy nanocomposites surfaces based on mesoscopic microspheres, polymers and graphene flakes

    Science.gov (United States)

    Alekseev, S. A.; Dmitriev, A. S.; Dmitriev, A. A.; Makarov, P. G.; Mikhailova, I. A.

    2017-11-01

    In recent years, there has been a great interest in the development and creation of new functional energy materials, including for improving the energy efficiency of power equipment and for effectively removing heat from energy devices, microelectronics and optoelectronics (power micro electronics, supercapacitors, cooling of processors, servers and Data centers). In this paper, the technology of obtaining a new nanocomposite based on mesoscopic microspheres, polymers and graphene flakes is considered. The methods of sequential production of functional materials from graphite flakes of different volumetric concentration using polymers based on epoxy resins and polyimide, as well as the addition of a mesoscopic medium in the form of monodisperse microspheres are described. The data of optical and electron microscopy of such nanocomposites are presented, the main problems in the appearance of defects in such materials are described, the possibilities of their elimination by the selection of different concentrations and sizes of the components. Data are given on the measurement of the hysteresis of the contact angle and the evaporation of droplets on similar substrates. The results of studying the mechanical, electrophysical and thermal properties of such nanocomposites are presented. Particular attention is paid to the investigation of the thermal conductivity of these nanocomposites with respect to the creation of thermal interface materials for cooling devices of electronics, optoelectronics and power engineering.

  15. Renewable Energy for Electric Vehicles : Price Based Charging Coordination

    NARCIS (Netherlands)

    Richstein, J.C.; Schuller, A.; Dinther, C.; Ketter, W.; Weinhardt, C.

    2012-01-01

    In this paper we investigate the charging coordination of battery electric vehicles (BEV) with respect to the availability of intermittent renewable energy generation considering individual real world driving profiles in a deterministic simulation based analysis, mapping a part of the German power

  16. Low-energy nuclear reactions with double-solenoid-based ...

    Indian Academy of Sciences (India)

    The University of Notre Dame, USA (Becchetti et al, Nucl. Instrum. Methods Res. A505, 377 (2003)) and later the University of São Paulo, Brazil (Lichtenthaler et al, Eur. Phys. J. A25, S-01, 733 (2005)) adopted a system based on superconducting solenoids to produce low-energy radioactive nuclear beams. In these systems ...

  17. Nanostructured Mo-based electrode materials for electrochemical energy storage.

    Science.gov (United States)

    Hu, Xianluo; Zhang, Wei; Liu, Xiaoxiao; Mei, Yueni; Huang, Yunhui

    2015-04-21

    The development of advanced energy storage devices is at the forefront of research geared towards a sustainable future. Nanostructured materials are advantageous in offering huge surface to volume ratios, favorable transport features, and attractive physicochemical properties. They have been extensively explored in various fields of energy storage and conversion. This review is focused largely on the recent progress in nanostructured Mo-based electrode materials including molybdenum oxides (MoO(x), 2 ≤ x ≤ 3), dichalconides (MoX2, X = S, Se), and oxysalts for rechargeable lithium/sodium-ion batteries, Mg batteries, and supercapacitors. Mo-based compounds including MoO2, MoO3, MoO(3-y) (0 nanostructured Mo-based compounds, as well as their energy storage applications in lithium/sodium-ion batteries, Mg batteries, and pseudocapacitors. The relationship between nanoarchitectures and electrochemical performances as well as the related charge-storage mechanism is discussed. Moreover, remarks on the challenges and perspectives of Mo-containing compounds for further development in electrochemical energy storage applications are proposed. This review sheds light on the sustainable development of advanced rechargeable batteries and supercapacitors with nanostructured Mo-based electrode materials.

  18. Energy Efficient Routing in Wireless Sensor Networks based on Ant ...

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    2013-09-01

    Sep 1, 2013 ... Ant Colony Optimization, a swarm intelligence based optimization technique, has been successfully used in network routing. In this paper, we introduce a heuristic way to reduce energy consumption in WSNs routing process using Ant Colony Optimization. We introduce three Ant Colony Optimization ...

  19. A Solution Based on Bluetooth Low Energy for Smart Home Energy Management

    OpenAIRE

    Collotta, Mario; Pau, Giovanni

    2015-01-01

    The research and the implementation of home automation are getting more popular because the Internet of Things holds promise for making homes smarter through wireless technologies. The installation of systems based on wireless networks can play a key role also in the extension of the smart grid towards smart homes, that can be deemed as one of the most important components of smart grids. This paper proposes a fuzzy-based solution for smart energy management in a home automation wireless netw...

  20. Assessment and Decomposition of Total Factor Energy Efficiency: An Evidence Based on Energy Shadow Price in China

    OpenAIRE

    Peihao Lai; Minzhe Du; Bing Wang; Ziyue Chen

    2016-01-01

    By adopting an energy-input based directional distance function, we calculated the shadow price of four types of energy (i.e., coal, oil, gas and electricity) among 30 areas in China from 1998 to 2012. Moreover, a macro-energy efficiency index in China was estimated and divided into intra-provincial technical efficiency, allocation efficiency of energy input structure and inter-provincial energy allocation efficiency. It shows that total energy efficiency has decreased in recent years, where ...

  1. The Influence of Evidence-Based Surgical Indications and Techniques on Failure Rates After Arthroscopic Shoulder Stabilization in the Contact or Collision Athlete With Anterior Shoulder Instability.

    Science.gov (United States)

    Leroux, Timothy S; Saltzman, Bryan M; Meyer, Maximilian; Frank, Rachel M; Bach, Bernard R; Cole, Brian J; Romeo, Anthony A; Verma, Nikhil N

    2017-04-01

    It has been reported that arthroscopic shoulder stabilization yields higher rates of failure in contact or collision athletes as compared with open shoulder stabilization; however, this is largely based upon studies that do not employ modern, evidence-based surgical indications and techniques for arthroscopic shoulder stabilization. To (1) determine the pooled failure rate across all studies reporting failure after primary arthroscopic shoulder stabilization for anterior shoulder instability in contact or collision athletes and (2) stratify failure rates according to studies that use evidence-based surgical indications and techniques. Systematic review. A review of PubMed, Medline, and Embase was performed to identify all clinical studies with a minimum of 1-year follow-up that reported failure rates after arthroscopic shoulder stabilization for anterior shoulder instability in contact or collision athletes. Data pertaining to patient demographics, clinical and radiographic preoperative assessment, surgical indications, surgical technique, rehabilitation, and outcome were collected from each included study. An overall failure rate was determined across all included studies. After this, a secondary literature review was performed to identify factors related to patient selection and surgical technique that significantly influence failure after primary arthroscopic shoulder stabilization. Failure rates were then determined among included studies that used these evidence-based indications and techniques. Overall, 26 studies reporting on 779 contact or collision athletes met the inclusion criteria. The mean patient age was 19.9 years, 90.3% were male, and the most common sport was rugby. There was considerable variability in the reporting of patient demographics, preoperative assessment, surgical indications, surgical technique, and patient outcomes. Across all included studies, the pooled failure rate after arthroscopic shoulder stabilization in the contact or

  2. Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger

    Science.gov (United States)

    Berry, G.F.; Minkov, V.; Petrick, M.

    1981-11-02

    A magnetohydrodynamic (MHD) power generating system is described in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

  3. Preventative maintenance cycle of contact switches for nuclear power plants based on lifetime assessment and economic analysis

    International Nuclear Information System (INIS)

    Shi Jie

    2010-01-01

    An approach to determine the preventive maintenance cycle was proposed in consideration of the lifetime, optimal cost and economy. Two parameters Weibull distribution was used to calculate the lifetime of contact switch. The block replacement model and age replacement model were built with the objective of optimal cost, and the preventive replacement cycle was accounted. Eight proposals for preventive replacement cycle were given. Economy model was applied to assess those proposals and the optimal proposal was confirmed. (authors)

  4. Resonant characteristics and sensitivity dependency on the contact surface in QCM-micropillar-based system of coupled resonator sensors

    International Nuclear Information System (INIS)

    Kashan, M A M; Kalavally, V; Ramakrishnan, N; Lee, H W

    2016-01-01

    We report the characteristics and sensitivity dependence over the contact surface in coupled resonating sensors (CRSs) made of high aspect ratio resonant micropillars attached to a quartz crystal microbalance (QCM). Through experiments and simulation, we observed that when the pillars of resonant heights were placed in maximum displacement regions the resonance frequency of the QCM increased following the coupled resonance characteristics, as the pillar offered elastic loading to the QCM surface. However, the same pillars when placed in relatively lower displacement regions, in spite of their resonant dimension, offered inertial loading and resulted in a decrease in QCM resonance frequency, as the displacement amplitude was insufficient to couple the vibrations from the QCM to the pillars. Accordingly, we discovered that the coupled resonance characteristics not only depend on the resonant structure dimensions but also on the contact regions in the acoustic device. Further analysis revealed that acoustic pressure at the contact surface also influences the resonance frequency characteristics and sensitivity of the CRS. To demonstrate the significance of the present finding for sensing applications, humidity sensing is considered as the example measurand. When a sensing medium made of resonant SU-8 pillars was placed in a maximum displacement region on a QCM surface, the sensitivity increased by 14 times in comparison to a resonant sensing medium placed in a lower displacement region of a QCM surface. (paper)

  5. Common Allergens Identified Based on Patch Test Results in Patients with Suspected Contact Dermatitis of the Scalp.

    Science.gov (United States)

    Aleid, Nouf M; Fertig, Raymond; Maddy, Austin; Tosti, Antonella

    2017-03-01

    Contact dermatitis of the scalp is common and might be caused by many chemicals including metals, ingredients of shampoos and conditioners, dyes, or other hair treatments. Eliciting a careful history and patch tests are necessary to identify the responsible allergen and prevent relapses. To identify allergens that may cause contact dermatitis of the scalp by reviewing patch test results. We reviewed the records of 1,015 patients referred for patch testing at the Dermatology Department of the University of Miami. A total of 226 patients (205 females and 21 males) with suspected scalp contact dermatitis were identified, and the patch test results and clinical data for those patients were analyzed. Most patients were referred for patch testing from a specialized hair clinic at our institution. The most common allergens in our study population were nickel (23.8%), cobalt (21.0%), balsam of Peru (18.2%), fragrance mix (14.4%), carba mix (11.6%), and propylene glycol (PG) (8.8%). The majority of patients were females aged 40-59 years, and scalp itching or burning were reported as the most common symptom. Frequent sources of allergens for metals include hair clasps, pins, and brushes, while frequent sources of allergens for preservatives, fragrance mix, and balsam of Peru include shampoos, conditioners, and hair gels. Frequent sources of allergens for PG include topical medications.

  6. Structural changes of electron and ion beam-deposited contacts in annealed carbon-based electrical devices

    KAUST Repository

    Batra, Nitin M

    2015-10-09

    The use of electron and ion beam deposition to make devices containing discrete nanostructures as interconnectors is a well-known nanofabrication process. Classically, one-dimensional materials such as carbon nanotubes (CNTs) have been electrically characterized by resorting to these beam deposition methods. While much attention has been given to the interconnectors, less is known about the contacting electrodes (or leads). In particular, the structure and chemistry of the electrode–interconnector interface is a topic that deserves more attention, as it is critical to understand the device behavior. Here, the structure and chemistry of Pt electrodes, deposited either with electron or ion beams and contacted to a CNT, are analyzed before and after thermally annealing the device in a vacuum. Free-standing Pt nanorods, acting as beam-deposited electrode models, are also characterized pre- and post-annealing. Overall, the as-deposited leads contain a non-negligible amount of amorphous carbon that is consolidated, upon heating, as a partially graphitized outer shell enveloping a Pt core. This observation raises pertinent questions regarding the definition of electrode–nanostructure interfaces in electrical devices, in particular long-standing assumptions of metal-CNT contacts fabricated by direct beam deposition methods.

  7. Resonant characteristics and sensitivity dependency on the contact surface in QCM-micropillar-based system of coupled resonator sensors

    Science.gov (United States)

    Kashan, M. A. M.; Kalavally, V.; Lee, H. W.; Ramakrishnan, N.

    2016-05-01

    We report the characteristics and sensitivity dependence over the contact surface in coupled resonating sensors (CRSs) made of high aspect ratio resonant micropillars attached to a quartz crystal microbalance (QCM). Through experiments and simulation, we observed that when the pillars of resonant heights were placed in maximum displacement regions the resonance frequency of the QCM increased following the coupled resonance characteristics, as the pillar offered elastic loading to the QCM surface. However, the same pillars when placed in relatively lower displacement regions, in spite of their resonant dimension, offered inertial loading and resulted in a decrease in QCM resonance frequency, as the displacement amplitude was insufficient to couple the vibrations from the QCM to the pillars. Accordingly, we discovered that the coupled resonance characteristics not only depend on the resonant structure dimensions but also on the contact regions in the acoustic device. Further analysis revealed that acoustic pressure at the contact surface also influences the resonance frequency characteristics and sensitivity of the CRS. To demonstrate the significance of the present finding for sensing applications, humidity sensing is considered as the example measurand. When a sensing medium made of resonant SU-8 pillars was placed in a maximum displacement region on a QCM surface, the sensitivity increased by 14 times in comparison to a resonant sensing medium placed in a lower displacement region of a QCM surface.

  8. Ultraviolet GaN photodetectors on Si via oxide buffer heterostructures with integrated short period oxide-based distributed Bragg reflectors and leakage suppressing metal-oxide-semiconductor contacts

    Science.gov (United States)

    Szyszka, A.; Lupina, L.; Lupina, G.; Schubert, M. A.; Zaumseil, P.; Haeberlen, M.; Storck, P.; Thapa, S. B.; Schroeder, T.

    2014-08-01

    Based on a novel double step oxide buffer heterostructure approach for GaN integration on Si, we present an optimized Metal-Semiconductor-Metal (MSM)-based Ultraviolet (UV) GaN photodetector system with integrated short-period (oxide/Si) Distributed Bragg Reflector (DBR) and leakage suppressing Metal-Oxide-Semiconductor (MOS) electrode contacts. In terms of structural properties, it is demonstrated by in-situ reflection high energy electron diffraction and transmission electron microscopy-energy dispersive x-ray studies that the DBR heterostructure layers grow with high thickness homogeneity and sharp interface structures sufficient for UV applications; only minor Si diffusion into the Y2O3 films is detected under the applied thermal growth budget. As revealed by comparative high resolution x-ray diffraction studies on GaN/oxide buffer/Si systems with and without DBR systems, the final GaN layer structure quality is not significantly influenced by the growth of the integrated DBR heterostructure. In terms of optoelectronic properties, it is demonstrated that—with respect to the basic GaN/oxide/Si system without DBR—the insertion of (a) the DBR heterostructures and (b) dark current suppressing MOS contacts enhances the photoresponsivity below the GaN band-gap related UV cut-off energy by almost up to two orders of magnitude. Given the in-situ oxide passivation capability of grown GaN surfaces and the one order of magnitude lower number of superlattice layers in case of higher refractive index contrast (oxide/Si) systems with respect to classical III-N DBR superlattices, virtual GaN substrates on Si via functional oxide buffer systems are thus a promising robust approach for future GaN-based UV detector technologies.

  9. Metal hydride-based thermal energy storage systems

    Science.gov (United States)

    Vajo, John J.; Fang, Zhigang

    2017-10-03

    The invention provides a thermal energy storage system comprising a metal-containing first material with a thermal energy storage density of about 1300 kJ/kg to about 2200 kJ/kg based on hydrogenation; a metal-containing second material with a thermal energy storage density of about 200 kJ/kg to about 1000 kJ/kg based on hydrogenation; and a hydrogen conduit for reversibly transporting hydrogen between the first material and the second material. At a temperature of 20.degree. C. and in 1 hour, at least 90% of the metal is converted to the hydride. At a temperature of 0.degree. C. and in 1 hour, at least 90% of the metal hydride is converted to the metal and hydrogen. The disclosed metal hydride materials have a combination of thermodynamic energy storage densities and kinetic power capabilities that previously have not been demonstrated. This performance enables practical use of thermal energy storage systems for electric vehicle heating and cooling.

  10. Energy Efficient Wireless Sensor Network Modelling Based on Complex Networks

    Directory of Open Access Journals (Sweden)

    Lin Xiao

    2016-01-01

    Full Text Available The power consumption and energy efficiency of wireless sensor network are the significant problems in Internet of Things network. In this paper, we consider the network topology optimization based on complex network theory to solve the energy efficiency problem of WSN. We propose the energy efficient model of WSN according to the basic principle of small world from complex networks. Small world network has clustering features that are similar to that of the rules of the network but also has similarity to random networks of small average path length. It can be utilized to optimize the energy efficiency of the whole network. Optimal number of multiple sink nodes of the WSN topology is proposed for optimizing energy efficiency. Then, the hierarchical clustering analysis is applied to implement this clustering of the sensor nodes and pick up the sink nodes from the sensor nodes as the clustering head. Meanwhile, the update method is proposed to determine the sink node when the death of certain sink node happened which can cause the paralysis of network. Simulation results verify the energy efficiency of the proposed model and validate the updating of the sink nodes to ensure the normal operation of the WSN.

  11. A Simple Approach to Characterize Gas-Aqueous Liquid Two-phase Flow Configuration Based on Discrete Solid-Liquid Contact Electrification.

    Science.gov (United States)

    Choi, Dongwhi; Lee, Donghyeon; Kim, Dong Sung

    2015-10-14

    In this study, we first suggest a simple approach to characterize configuration of gas-aqueous liquid two-phase flow based on discrete solid-liquid contact electrification, which is a newly defined concept as a sequential process of solid-liquid contact and successive detachment of the contact liquid from the solid surface. This approach exhibits several advantages such as simple operation, precise measurement, and cost-effectiveness. By using electric potential that is spontaneously generated by discrete solid-liquid contact electrification, the configurations of the gas-aqueous liquid two-phase flow such as size of a gas slug and flow rate are precisely characterized. According to the experimental and numerical analyses on parameters that affect electric potential, gas slugs have been verified to behave similarly to point electric charges when the measuring point of the electric potential is far enough from the gas slug. In addition, the configuration of the gas-aqueous liquid two-phase microfluidic system with multiple gas slugs is also characterized by using the presented approach. For a proof-of-concept demonstration of using the proposed approach in a self-triggered sensor, a gas slug detector with a counter system is developed to show its practicality and applicability.

  12. A Fuzzy-Based Building Energy Management System for Energy Efficiency

    Directory of Open Access Journals (Sweden)

    José L. Hernández

    2018-01-01

    Full Text Available Information and communication technologies (ICT offer immense potential to improve the energetic performance of buildings. Additionally, common building control systems are typically based on simple decision-making tools, which possess the ability to obtain controllable parameters for indoor temperatures. Nevertheless, the accuracy of such common building control systems is improvable with the integration of advanced decision-making techniques embedded into software and energy management tools. This paper presents the design of a building energy management system (BEMS, which is currently under development, and that makes use of artificial intelligence for the automated decision-making process required for optimal comfort of occupants and utilization of renewables for achieving energy-efficiency in buildings. The research falls under the scope of the H2020 project BREASER which implements fuzzy logic with the aim of governing the energy resources of a school in Turkey, which has been renovated with a ventilated façade with integrated renewable energy sources (RES. The BRESAER BEMS includes prediction techniques that increase the accuracy of common BEMS tools, and subsequent energy savings, while ensuring the indoor thermal comfort of the building occupants. In particular, weather forecast and simulation strategies are integrated into the functionalities of the overall system. By collecting the aforementioned information, the BEMS makes decisions according to a well-established selection of key performance indicators (KPIs with the objective of providing a quantitative comparable value to determine new actuation parameters.

  13. Graphene-Based Integrated Photovoltaic Energy Harvesting/Storage Device.

    Science.gov (United States)

    Chien, Chih-Tao; Hiralal, Pritesh; Wang, Di-Yan; Huang, I-Sheng; Chen, Chia-Chun; Chen, Chun-Wei; Amaratunga, Gehan A J

    2015-06-24

    Energy scavenging has become a fundamental part of ubiquitous sensor networks. Of all the scavenging technologies, solar has the highest power density available. However, the energy source is erratic. Integrating energy conversion and storage devices is a viable route to obtain self-powered electronic systems which have long-term maintenance-free operation. In this work, we demonstrate an integrated-power-sheet, consisting of a string of series connected organic photovoltaic cells (OPCs) and graphene supercapacitors on a single substrate, using graphene as a common platform. This results in lighter and more flexible power packs. Graphene is used in different forms and qualities for different functions. Chemical vapor deposition grown high quality graphene is used as a transparent conductor, while solution exfoliated graphene pastes are used as supercapacitor electrodes. Solution-based coating techniques are used to deposit the separate components onto a single substrate, making the process compatible with roll-to-roll manufacture. Eight series connected OPCs based on poly(3-hexylthiophene)(P3HT):phenyl-C61-butyric acid methyl ester (PC60 BM) bulk-heterojunction cells with aluminum electrodes, resulting in a ≈5 V open-circuit voltage, provide the energy harvesting capability. Supercapacitors based on graphene ink with ≈2.5 mF cm(-2) capacitance provide the energy storage capability. The integrated-power-sheet with photovoltaic (PV) energy harvesting and storage functions had a mass of 0.35 g plus the substrate. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. EFRC: Polymer-Based Materials for Harvesting Solar Energy (stimulus)"

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Thomas P. [Univ. of Massachusetts, Amherst, MA (United States)

    2016-12-08

    The University of Massachusetts Amherst is proposing an Energy Frontier Research Center (EFRC) on Polymer-Based Materials for Harvesting Solar Energy that will integrate the widely complementary experimental and theoretical expertise of 23 faculty at UMass-Amherst Departments with researchers from the University of Massachusetts Lowell, University of Pittsburgh, the Pennsylvania State University and Konarka Technologies, Inc. Collaborative efforts with researchers at the Oak Ridge National Laboratory, the University of Bayreuth, Seoul National University and Tohoku University will complement and expand the experimental efforts in the EFRC. Our primary research aim of this EFRC is the development of hybrid polymer-based devices with efficiencies more than twice the current organic-based devices, by combining expertise in the design and synthesis of photoactive polymers, the control and guidance of polymer-based assemblies, leadership in nanostructured polymeric materials, and the theory and modeling of non-equilibrium structures. A primary goal of this EFRC is to improve the collection and conversion efficiency of a broader spectral range of solar energy using the directed self-assembly of polymer-based materials so as to optimize the design and fabrication of inexpensive devices.

  15. Energy harvesting “3-D knitted spacer” based piezoelectric textiles

    Science.gov (United States)

    Anand, S.; Soin, N.; Shah, T. H.; Siores, E.

    2016-07-01

    The piezoelectric effect in Poly(vinylidene fluoride), PVDF, was discovered over four decades ago and since then, significant work has been carried out aiming at the production of high p-phase fibres and their integration into fabric structures for energy harvesting. However, little work has been done in the area of production of “true piezoelectric fabric structures” based on flexible polymeric materials such as PVDF. In this work, we demonstrate “3-D knitted spacer” technology based all-fibre piezoelectric fabrics as power generators and energy harvesters. The knitted single-structure piezoelectric generator consists of high p-phase (~80%) piezoelectric PVDF monofilaments as the spacer yarn interconnected between silver (Ag) coated polyamide multifilament yarn layers acting as the top and bottom electrodes. The novel and unique textile structure provides an output power density in the range of 1.105.10 gWcm-2 at applied impact pressures in the range of 0.02-0.10 MPa, thus providing significantly higher power outputs and efficiencies over the existing 2-D woven and nonwoven piezoelectric structures. The high energy efficiency, mechanical durability and comfort of the soft, flexible and all-fibre based power generator is highly attractive for a variety of potential applications such as wearable electronic systems and energy harvesters charged from ambient environment or by human movement.

  16. Energy and Charge Transfer in Dinuclear Ru-based Complexes

    Science.gov (United States)

    Kleiman, Valeria

    2014-03-01

    In this work, the excited state dynamics of a series of dinuclear compounds combining Ru based cromophores with M =Ru(II), Fe(II), Fe(III), Cr(III) are explored. Ru- μ-NC-M dimers are good candidates to investigate the competition between electron and energy transfer in arrays of chromophores. The presence of a μ-NC bridge affords a strong coupling between the moieties without providing acceptor states that might act as electron traps. Polypyridyl Ru based compounds play an important role on light-harvesting antennas for energy conversion. With proper knowledge of the excited state dynamics, multinuclear arrays of chromophores can be developed. Our studies focus on (i) energy/electron transfer from the Ru(II) to a 2nd M center through the cyanide bridge, and (ii) geometry changes due to the exchange of one of the Ru(II) polypiridyl ligands . Broadband ultrafast spectroscopy shows excited state dynamics in the psec time regime. These dynamics depend strongly on the nature of the acceptor and the orientation of the ligand involved in the photoinduced transition. Hence, the competition between energy and electron transfer across the bridge is modulated by the selective choice of the secondary M center. We conclude that transition metals from the 3rd row are good candidates for longer arrays since their lack of low-lying MC states precludes thermal deactivation. This work is based upon work supported by NSF (CHE-1058638) and CONICET.

  17. Developing competence based qualification system in the nuclear energy sector

    International Nuclear Information System (INIS)

    Ceclan, Mihail

    2016-01-01

    The Institute for Energy and Transport of the Joint Research Centre, European Commission, developed a strategy and road map for ECVET implementation. The JRC road map for European Credit System for Vocational Education and Training (ECVET) implementation has reached the stage of Competence-Based Qualification System development. The Competence-Based Qualification System can help bridge the gap between Human Resources demand and supply in the nuclear market by structuring qualifications in small independent parts. This very specific ECVET feature of a qualification, facilitates the process of competences accumulation and the lifelong learning, mobility and flexible learning pathways. New developments are presented about the Competence-Based Qualification System development for the nuclear energy sector.

  18. Developing competence based qualification system in the nuclear energy sector

    Energy Technology Data Exchange (ETDEWEB)

    Ceclan, Mihail [European Commission, Petten (Netherlands). Inst. for Energy and Transport

    2016-04-15

    The Institute for Energy and Transport of the Joint Research Centre, European Commission, developed a strategy and road map for ECVET implementation. The JRC road map for European Credit System for Vocational Education and Training (ECVET) implementation has reached the stage of Competence-Based Qualification System development. The Competence-Based Qualification System can help bridge the gap between Human Resources demand and supply in the nuclear market by structuring qualifications in small independent parts. This very specific ECVET feature of a qualification, facilitates the process of competences accumulation and the lifelong learning, mobility and flexible learning pathways. New developments are presented about the Competence-Based Qualification System development for the nuclear energy sector.

  19. Reliability-Based Structural Optimization of Wave Energy Converters

    DEFF Research Database (Denmark)

    Ambühl, Simon; Kramer, Morten; Sørensen, John Dalsgaard

    2014-01-01

    More and more wave energy converter (WEC) concepts are reaching prototype level. Once the prototype level is reached, the next step in order to further decrease the levelized cost of energy (LCOE) is optimizing the overall system with a focus on structural and maintenance (inspection) costs...... objectives and will be located at different locations, as well as receive various subsidies. These points should be accounted for when performing structural optimizations of WECs. An illustrative example on the gravity-based foundation of the Wavestar device is performed showing how structural design can...... be optimized taking target reliability levels and different structural failure modes due to extreme loads into account....

  20. Energy reversible switching from amorphous metal based nanoelectromechanical switch

    KAUST Repository

    Mayet, Abdulilah M.

    2013-08-01

    We report observation of energy reversible switching from amorphous metal based nanoelectromechanical (NEM) switch. For ultra-low power electronics, NEM switches can be used as a complementary switching element in many nanoelectronic system applications. Its inherent zero power consumption because of mechanical detachment is an attractive feature. However, its operating voltage needs to be in the realm of 1 volt or lower. Appropriate design and lower Young\\'s modulus can contribute achieving lower operating voltage. Therefore, we have developed amorphous metal with low Young\\'s modulus and in this paper reporting the energy reversible switching from a laterally actuated double electrode NEM switch. © 2013 IEEE.

  1. Feature Recognition of Froth Images Based on Energy Distribution Characteristics

    Directory of Open Access Journals (Sweden)

    WU Yanpeng

    2014-09-01

    Full Text Available This paper proposes a determining algorithm for froth image features based on the amplitude spectrum energy statistics by applying Fast Fourier Transformation to analyze the energy distribution of various-sized froth. The proposed algorithm has been used to do a froth feature analysis of the froth images from the alumina flotation processing site, and the results show that the consistency rate reaches 98.1 % and the usability rate 94.2 %; with its good robustness and high efficiency, the algorithm is quite suitable for flotation processing state recognition.

  2. Web-based energy information systems for energy management and demand response in commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Motegi, Naoya; Piette, Mary Ann; Kinney, Satkartar; Herter, Karen

    2003-04-18

    Energy Information Systems (EIS) for buildings are becoming widespread in the U.S., with more companies offering EIS products every year. As a result, customers are often overwhelmed by the quickly expanding portfolio of EIS feature and application options, which have not been clearly identified for consumers. The object of this report is to provide a technical overview of currently available EIS products. In particular, this report focuses on web-based EIS products for large commercial buildings, which allow data access and control capabilities over the Internet. EIS products combine software, data acquisition hardware, and communication systems to collect, analyze and display building information to aid commercial building energy managers, facility managers, financial managers and electric utilities in reducing energy use and costs in buildings. Data types commonly processed by EIS include energy consumption data; building characteristics; building system data, such as heating, ventilation, and air-conditioning (HVAC) and lighting data; weather data; energy price signals; and energy demand-response event information. This project involved an extensive review of research and trade literature to understand the motivation for EIS technology development. This study also gathered information on currently commercialized EIS. This review is not an exhaustive analysis of all EIS products; rather, it is a technical framework and review of current products on the market. This report summarizes key features available in today's EIS, along with a categorization framework to understand the relationship between EIS, Energy Management and Control Systems (EMCSs), and similar technologies. Four EIS types are described: Basic Energy Information Systems (Basic-EIS); Demand Response Systems (DRS); Enterprise Energy Management (EEM); and Web-based Energy Management and Control Systems (Web-EMCS). Within the context of these four categories, the following characteristics of EIS

  3. Qt based control system software for Low Energy Accelerator Facility

    International Nuclear Information System (INIS)

    Basu, A.; Singh, S.; Nagraju, S.B.V.; Gupta, S.; Singh, P.

    2012-01-01

    Qt based control system software for Low Energy Accelerating Facility (LEAF) is operational at Bhabha Atomic Research Centre (BARC), Trombay, Mumbai. LEAF is a 50 keV negative ion electrostatic accelerator based on SNICS ion source. Control system uses Nokia Trolltech's QT 4.x API for control system software. Ni 6008 USB based multifunction cards has been used for control and read back field equipments such as power supplies, pumps, valves etc. Control system architecture is designed to be client server. Qt is chosen for its excellent GUI capability and platform independent nature. Control system follows client server architecture. The paper will describe the control system. (author)

  4. Interfacial Phenomena in Silver-Copper Sliding Electrical Contact System.

    Science.gov (United States)

    Garshasb, Masoud

    Copper-silver sliding electrical contact systems have been investigated using modern surface science and microstructural characterization methods. The experiments involve current carrying metallic brushes sliding on a sputter cleaned rotating slip ring in an ultra high vacuum system. The ambient (and lubricant) of the experiment was water saturated CO(,2) at atmospheric pressure. The characterization techniques included Auger electron spectroscopy (AES), scanning electron microscopy (SEM), x-ray energy spectroscopy (XES), reflection high energy electron diffraction (RHEED), x-ray diffraction (XRD), and in-situ measurements of contact resistance. The electrical contact systems that were studied included homogeneous contacts (Cu/Cu, Ag/Ag) and heterogeneous contacts (Cu/Ag, Ag/Cu). Contact currents ranging from 0 to 50 A were used. In each case the wear particles were characterized by their shape and composition. For the case of heterogeneous contacts, the slip ring surface composition was determined by AES and the concentrations of the elements in the wear debris were plotted versus the contact current to determine the role of current in the Cu-Ag system. Based on the AES and SEM/XES results, some of the characteristic features of the most frequently occurring wear particles are explained and the mechanisms for metal transfer across the interface and wear particle formation are discussed. X-ray diffraction analyses of the mean crystallite size, the non uniform strain and the average lattice parameter of the debris from Cu-Cu systems are presented as a function of contact current. The dependence of the x-ray parameter on current reflects the annealing that takes place at higher currents. This result was supported by RHEED analyses of the wear particles. These various studies have clarified many of the complex mechanisms involved in electrical contact processes.

  5. Inventory of data bases, graphics packages, and models in Department of Energy laboratories

    International Nuclear Information System (INIS)

    Shriner, C.R.; Peck, L.J.

    1978-11-01

    A central inventory of energy-related environmental bibliographic and numeric data bases, graphics packages, integrated hardware/software systems, and models was established at Oak Ridge National Laboratory in an effort to make these resources at Department of Energy (DOE) laboratories better known and available to researchers and managers. This inventory will also serve to identify and avoid duplication among laboratories. The data were collected at each DOE laboratory, then sent to ORNL and merged into a single file. This document contains the data from the merged file. The data descriptions are organized under major data types: data bases, graphics packages, integrated hardware/software systems, and models. The data include descriptions of subject content, documentation, and contact persons. Also provided are computer data such as media on which the item is available, size of the item, computer on which the item executes, minimum hardware configuration necessary to execute the item, software language(s) and/or data base management system utilized, and character set used. For the models, additional data are provided to define the model more accurately. These data include a general statement of algorithms, computational methods, and theories used by the model; organizations currently using the model; the general application area of the model; sources of data utilized by the model; model validation methods, sensitivity analysis, and procedures; and general model classification. Data in this inventory will be available for on-line data retrieval on the DOE/RECON system

  6. Large deformation and adhesive contact studies of axisymmetric membranes.

    Science.gov (United States)

    Laprade, Evan J; Long, Rong; Pham, Jonathan T; Lawrence, Jimmy; Emrick, Todd; Crosby, Alfred J; Hui, Chung-Yuen; Shull, Kenneth R

    2013-02-05

    A model membrane contact system consisting of an acrylic copolymer membrane and a PDMS substrate was utilized to evaluate a recently developed nonlinear large-deformation adhesive contact analysis. Direct measurements of the local membrane apex strain during noncontact inflation indicated that the neo-Hookean model provides an accurate measure of membrane strain and supports its use as the strain energy function for the analysis. Two membrane contact geometries, exhibiting significantly different strain distributions during withdrawal, were investigated. The first examines the wet contact of an air pressurized membrane. The second looks at the dry contact of a fluid deformed membrane in which a stepper motor controls membrane-substrate separation. A time-dependent modulus emerges from the analysis, with principal tensions obtained from a comparison of predicted and experimental membrane profiles. The applicability of this numerical analysis for determining membrane tension, however, is limited by wrinkling instabilities and viscoelasticity. For this reason, a conceptually simpler method, based on the direct measurement of the membrane tension and contact angle, was also utilized. The traditional peel energy defined with this direct measurement accurately described the membrane/substrate adhesive interactions, giving well-defined peel energies that were independent of the detailed strain state of the membrane.

  7. An energy-based beam hardening model in tomography

    Energy Technology Data Exchange (ETDEWEB)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E [Vision Lab, Physics Departement, University of Antwerp (RUCA) (Belgium)

    2002-12-07

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography ({mu}CT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages.

  8. An energy-based beam hardening model in tomography

    International Nuclear Information System (INIS)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E

    2002-01-01

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography (μCT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages

  9. Optimal weight based on energy imbalance and utility maximization

    Science.gov (United States)

    Sun, Ruoyan

    2016-01-01

    This paper investigates the optimal weight for both male and female using energy imbalance and utility maximization. Based on the difference of energy intake and expenditure, we develop a state equation that reveals the weight gain from this energy gap. We ​construct an objective function considering food consumption, eating habits and survival rate to measure utility. Through applying mathematical tools from optimal control methods and qualitative theory of differential equations, we obtain some results. For both male and female, the optimal weight is larger than the physiologically optimal weight calculated by the Body Mass Index (BMI). We also study the corresponding trajectories to steady state weight respectively. Depending on the value of a few parameters, the steady state can either be a saddle point with a monotonic trajectory or a focus with dampened oscillations.

  10. A Belleville-spring-based electromagnetic energy harvester

    International Nuclear Information System (INIS)

    Castagnetti, Davide

    2015-01-01

    Energy harvesting from kinetic ambient energy is particularly effective to power autonomous sensors. This work proposes an innovative energy converter based on two counteracting Belleville springs and exploiting their peculiarity, for a height to thickness ratio equal to 1.414, of nearly zero stiffness over a wide deflection range. After analytical and numerical modelling a prototype is developed and experimentally investigated. The sub-optimal geometry of the commercial springs used in the prototype, together with a non-ideal response, makes the operating frequency for the prototype higher than in analytical and numerical predictions. Nevertheless, the harvester exhibits a significantly large bandwidth, together with a high output power, compared to similar solutions in the literature, for all the examined configurations and input excitations. (paper)

  11. Contact pin-printing of albumin-fungicide conjugate for silicon nitride-based sensors biofunctionalization: Multi-technique surface analysis for optimum immunoassay performance

    Energy Technology Data Exchange (ETDEWEB)

    Gajos, Katarzyna, E-mail: katarzyna.gajos@doctoral.uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Budkowski, Andrzej [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Tsialla, Zoi; Petrou, Panagiota [Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece); Awsiuk, Kamil; Dąbczyński, Paweł [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Bernasik, Andrzej [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków (Poland); Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Mickiewicza 30, 30-059 Kraków (Poland); Rysz, Jakub [M. Smoluchowski Institute of Physics, Jagiellonian University, Łojasiewicza, 11, 30-348 Kraków (Poland); Misiakos, Konstantinos; Raptis, Ioannis [Department of Microelectronics, Institute of Nanoscience and Nanotechnology, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece); Kakabakos, Sotirios [Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, NCSR Demokritos, P. Grigoriou & Neapoleos St., Aghia Paraksevi 15310, Athens (Greece)

    2017-07-15

    Highlights: • Contact pin-printing of overlapping probe spots and spotting by hand are compared. • Contact pin-printing favors probe immobilization with two-fold higher surface density. • Incomplete monolayer develops to bilayer as printing solution concentration increases. • Blocking molecules complete probe monolayer but reduce probe bilayer. • Surface immunoreaction increases with probe concentration in printing solution. - Abstract: Mass fabrication of integrated biosensors on silicon chips is facilitated by contact pin-printing, applied for biofunctionalization of individual Si{sub 3}N{sub 4}-based transducers at wafer-scale. To optimize the biofunctionalization for immunochemical (competitive) detection of fungicide thiabendazole (TBZ), Si{sub 3}N{sub 4} surfaces are modified with (3-aminopropyl)triethoxysilane and examined after: immobilization of BSA-TBZ conjugate (probe) from solutions with different concentration, blocking with bovine serum albumin (BSA), and immunoreaction with a mouse monoclonal antibody against TBZ. Nanostructure, surface density, probe composition and coverage uniformity of protein layers are evaluated with Atomic Force Microscopy, Spectroscopic Ellipsometry, Time-of-Flight Secondary Ion Mass Spectrometry and X-ray Photoelectron Spectroscopy. Contact pin-printing of overlapping probe spots is compared with hand spotted areas. Contact pin-printing resulted in two-fold increase of immobilized probe surface density as compared to hand spotting. Regarding BSA-TBZ immobilization, an incomplete monolayer develops into a bilayer as the concentration of BSA-TBZ molecules in the printing solution increases from 25 to 100 μg/mL. Upon blocking, however, a complete protein monolayer is formed for all the BSA-TBZ concentrations used. Free surface sites are filled with BSA for low surface coverage with BSA-TBZ, whereas loosely bound BSA-TBZ molecules are removed from the BSA-TBZ bilayer. As a consequence immunoreaction efficiency

  12. Super Capacitor Energy Storage Based MMC for Energy Harvesting in Mine Hoist Application

    Directory of Open Access Journals (Sweden)

    Xiaofeng Yang

    2017-09-01

    Full Text Available This paper proposes a super capacitor energy storage-based modular multilevel converter (SCES-MMC for mine hoist application. Different from the conventional MMCs, the sub-modules employ distributed super capacitor banks, which are designed to absorb the regenerative energy of mine hoist and released in the traction condition, so as to improve energy utilization efficiency. The key control technologies are introduced in detail, followed by analysis of the configuration and operation principles. The feasibility of the proposed SCES-MMC topology and the control theory are also verified. Simulation results show that SCES-MMC can adapt to the variable frequency speed regulation of the motor drive, which shows good application prospects in the future for medium- and high-voltage mine hoist systems.

  13. Dynamic soft tissue deformation estimation based on energy analysis

    Science.gov (United States)

    Gao, Dedong; Lei, Yong; Yao, Bin

    2016-10-01

    The needle placement accuracy of millimeters is required in many needle-based surgeries. The tissue deformation, especially that occurring on the surface of organ tissue, affects the needle-targeting accuracy of both manual and robotic needle insertions. It is necessary to understand the mechanism of tissue deformation during needle insertion into soft tissue. In this paper, soft tissue surface deformation is investigated on the basis of continuum mechanics, where a geometry model is presented to quantitatively approximate the volume of tissue deformation. The energy-based method is presented to the dynamic process of needle insertion into soft tissue based on continuum mechanics, and the volume of the cone is exploited to quantitatively approximate the deformation on the surface of soft tissue. The external work is converted into potential, kinetic, dissipated, and strain energies during the dynamic rigid needle-tissue interactive process. The needle insertion experimental setup, consisting of a linear actuator, force sensor, needle, tissue container, and a light, is constructed while an image-based method for measuring the depth and radius of the soft tissue surface deformations is introduced to obtain the experimental data. The relationship between the changed volume of tissue deformation and the insertion parameters is created based on the law of conservation of energy, with the volume of tissue deformation having been obtained using image-based measurements. The experiments are performed on phantom specimens, and an energy-based analytical fitted model is presented to estimate the volume of tissue deformation. The experimental results show that the energy-based analytical fitted model can predict the volume of soft tissue deformation, and the root mean squared errors of the fitting model and experimental data are 0.61 and 0.25 at the velocities 2.50 mm/s and 5.00 mm/s. The estimating parameters of the soft tissue surface deformations are proven to be useful

  14. Hybrid Carbon-Based Clathrates for Energy Storage

    Directory of Open Access Journals (Sweden)

    Kwai S. Chan

    2018-01-01

    Full Text Available Hybrid carbon–silicon, carbon–nitrogen, and carbon–boron clathrates are new classes of Type I carbon-based clathrates that have been identified by first-principles computational methods by substituting atoms on the carbon clathrate framework with Si, N, and/or B atoms. The hybrid framework is further stabilized by embedding appropriate guest atoms within the cavities of the cage structure. Series of hybrid carbon–silicon, carbon–boron, carbon–nitrogen, and carbon-silicon-nitrogen clathrates have been shown to exhibit small positive values for the energy of formation, indicating that they may be metastable compounds and amenable to fabrication. In this overview article, the energy of formation, elastic properties, and electronic properties of selected hybrid carbon-based clathrates are summarized. Theoretical calculations that explore the potential applications of hybrid carbon-based clathrates as energy storage materials, electronic materials, or hard materials are presented. The computational results identify compositions of hybrid carbon–silicon and carbon–nitrogen clathrates that may be considered as candidate materials for use as either electrode materials for Li-ion batteries or as hydrogen storage materials. Prior processing routes for fabricating selected hybrid carbon-based clathrates are highlighted and the difficulties encountered are discussed.

  15. Analysis of the peri-implant soft tissues in contact with zirconia abutments: an evidence-based literature review.

    Science.gov (United States)

    de Medeiros, Rodrigo Antonio; Vechiato-Filho, Aljomar José; Pellizzer, Eduardo Piza; Mazaro, Jose Vitor Quinelli; dos Santos, Daniela Micheline; Goiato, Marcelo Coelho

    2013-05-01

    The aim of this study is to evaluate through a literature review, the soft tissue response in contact with zirconia abutments, including case reports comparing prosthetics rehabilitations with zirconia and titanium abutments upto 3 years of follow-up as well as the factors that should be considered on implant's abutment selection. Metallic abutments can provide grayish color when in contact with thin soft tissues which may lead the implant prosthetic treatment to failure. In this context, the abutments of zirconia stand out because there is an excellent linking between esthetics and the health of peri-implant soft tissues. A consult of the published researches was made on the PubMed database from 2000 to September 2012. The including criteria were: literature reviews, clinical studies and case reports in English that focused on the response of the soft tissue in contact with zirconia implant abutments. The studies that were not in English and did not match the tackled issue were excluded. A total of 32 articles were found. According to the search strategy, just 16 articles were selected for this review. Three studies affirmed that zirconia abutments have an excellent soft tissue response; one study showed increased gingival recession with zirconia abutments and nine studies do not stand out any difference on biological behavior between titanium and zirconia abutments. Three studies affirmed that zirconia abutments provide natural gingival appearance, anatomic contour and greater esthetics. The use of zirconia abutments is recommended for anterior regions because of their greater optical properties and esthetic results and more studies should be performed and analyzed longitudinally regarding their biological response. The zirconia abutments have been established to be essential in order to achieve great esthetic results in cases of thin peri-implant soft tissues and in regions where the three-dimensional placement of implants is more superficial.

  16. A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

    International Nuclear Information System (INIS)

    Ayehunie, Seyoum; Snell, Maureen; Child, Matthew; Klausner, Mitchell

    2009-01-01

    A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N = 26) or non-allergens (N = 22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2 to 5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥1.5-fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity.

  17. A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

    Science.gov (United States)

    Ayehunie, Seyoum; Snell, Maureen; Child, Matthew; Klausner, Mitchell

    2009-01-01

    A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N=26) or non-allergens (N=22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2-5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥ 1.5 fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity. PMID:19665512

  18. Biomechanical simulation of needle insertion into cornea based on distortion energy failure criterion.

    Science.gov (United States)

    Su, Peng; Yang, Yang; Zhang, Leiyu; Huang, Long

    2016-01-01

    This paper is mainly about biomechanical behavior of needle insertion into cornea, and proposes a failure criterion to simulate the insertion process which has attracted considerable attention due to its importance for the minimally invasive treatment. In the process of needle insertion into cornea, tiny and complex insertion force is generated due to contact between needle and soft tissue. Based on the distortion energy theory, there is proposed a failure criterion of corneal material that can solve contact problem between rigid body and biological tissue in insertion simulation, where Cauchy stress of corneal material is the key to numerical calculation. A finite element model of in vivo cornea is built, and the cornea constrained by sclera is simplified to two layers containing epithelium and stroma. Considering the hyper-viscoelastic property of corneal material, insertion simulation is carried out. By insertion experiment, the insertion force increases with insertion depth accompanying obvious fluctuations. Different insertion forces are generated at different speeds. The punctured locations are obvious in the force-displacement curves. The results of insertion simulation are generally consistent with experimental data. Maps of von Mises stress reflect the tissue injury of the cornea during insertion process, and punctured status corresponds to the point in the curves. The ability of this study to reproduce the behavior of needle insertion into cornea opens a promising perspective for the control of robotic surgery operation as well as the real-time simulation of corneal suture surgery.

  19. Contact Angle Measurement in Lattice Boltzmann Method

    OpenAIRE

    Wen, Binghai; Huang, Bingfang; Qin, Zhangrong; Wang, Chunlei; Zhang, Chaoying

    2017-01-01

    Contact angle is an essential characteristic in wetting, capillarity and moving contact line; however, although contact angle phenomena are effectively simulated, an accurate and real-time measurement for contact angle has not been well studied in computational fluid dynamics, especially in dynamic environments. Here, we design a geometry-based mesoscopic scheme to onthesport measure the contact angle in the lattice Boltzmann method. The computational results without gravity effect are in exc...

  20. Thermal energy storage based on cementitious materials: A review

    Directory of Open Access Journals (Sweden)

    Khadim Ndiaye

    2018-01-01

    Full Text Available Renewable energy storage is now essential to enhance the energy performance of buildings and to reduce their environmental impact. Many heat storage materials can be used in the building sector in order to avoid the phase shift between solar radiation and thermal energy demand. However, the use of storage material in the building sector is hampered by problems of investment cost, space requirements, mechanical performance, material stability, and high storage temperature. Cementitious material is increasingly being used as a heat storage material thanks to its low price, mechanical performance and low storage temperature (generally lower than 100 °C. In addition, cementitious materials for heat storage have the prominent advantage of being easy to incorporate into the building landscape as self-supporting structures or even supporting structures (walls, floor, etc.. Concrete solutions for thermal energy storage are usually based on sensible heat transfer and thermal inertia. Phase Change Materials (PCM incorporated in concrete wall have been widely investigated in the aim of improving building energy performance. Cementitious material with high ettringite content stores heat by a combination of physical (adsorption and chemical (chemical reaction processes usable in both the short (daily, weekly and long (seasonal term. Ettringite materials have the advantage of high energy storage density at low temperature (around 60 °C. The encouraging experimental results in the literature on heat storage using cementitious materials suggest that they could be attractive in a number of applications. This paper summarizes the investigation and analysis of the available thermal energy storage systems using cementitious materials for use in various applications.