WorldWideScience

Sample records for unbalanced deoxynucleotide pools

  1. Thymidine kinase 2 (H126N) knockin mice show the essential role of balanced deoxynucleotide pools for mitochondrial DNA maintenance.

    Science.gov (United States)

    Akman, Hasan O; Dorado, Beatriz; López, Luis C; García-Cazorla, Angeles; Vilà, Maya R; Tanabe, Lauren M; Dauer, William T; Bonilla, Eduardo; Tanji, Kurenai; Hirano, Michio

    2008-08-15

    Mitochondrial DNA (mtDNA) depletion syndrome (MDS), an autosomal recessive condition, is characterized by variable organ involvement with decreased mtDNA copy number and activities of respiratory chain enzymes in affected tissues. MtDNA depletion has been associated with mutations in nine autosomal genes, including thymidine kinase (TK2), which encodes a ubiquitous mitochondrial protein. To study the pathogenesis of TK2-deficiency, we generated mice harboring an H126N Tk2 mutation. Homozygous Tk2 mutant (Tk2(-/-)) mice developed rapidly progressive weakness after age 10 days and died between ages 2 and 3 weeks. Tk2(-/-) animals showed Tk2 deficiency, unbalanced dNTP pools, mtDNA depletion and defects of respiratory chain enzymes containing mtDNA-encoded subunits that were most prominent in the central nervous system. Histopathology revealed an encephalomyelopathy with prominent vacuolar changes in the anterior horn of the spinal cord. The H126N TK2 mouse is the first knock-in animal model of human MDS and demonstrates that the severity of TK2 deficiency in tissues may determine the organ-specific phenotype.

  2. Deoxynucleotide-interconverting enzymes and the quantification of deoxynucleoside triphosphates in mammalian cells

    OpenAIRE

    Fuller, Steven A.; Hutton, John J.; Meier, John; Coleman, Mary Sue

    1982-01-01

    We have demonstrated that methanol extracts of human cells are heterogeneous with regard to content of dNDP (deoxynucleoside diphosphate) and dNMP (deoxynucleoside monophosphate) kinases. The presence of these enzymes can affect the reliability of techniques used to measure intracellular pools of deoxynucleotides. An optimized extraction procedure and enzymic assay for dNTP species in haematopoietic cells are described which provide sensitivity to measure 0.1–40pmol of dATP, dTTP and dGTP, an...

  3. Unbalanced field RF electron gun

    Science.gov (United States)

    Hofler, Alicia

    2013-11-12

    A design for an RF electron gun having a gun cavity utilizing an unbalanced electric field arrangement. Essentially, the electric field in the first (partial) cell has higher field strength than the electric field in the second (full) cell of the electron gun. The accompanying method discloses the use of the unbalanced field arrangement in the operation of an RF electron gun in order to accelerate an electron beam.

  4. Thymidine kinase 2 (H126N) knockin mice show the essential role of balanced deoxynucleotide pools for mitochondrial DNA maintenance

    OpenAIRE

    Akman, Hasan O.; Dorado, Beatriz; López, Luis C.; García-Cazorla, Ángeles; Vilà, Maya R.; Tanabe, Lauren M.; Dauer, William T.; Bonilla, Eduardo; Tanji, Kurenai; Hirano, Michio

    2008-01-01

    Mitochondrial DNA (mtDNA) depletion syndrome (MDS), an autosomal recessive condition, is characterized by variable organ involvement with decreased mtDNA copy number and activities of respiratory chain enzymes in affected tissues. MtDNA depletion has been associated with mutations in nine autosomal genes, including thymidine kinase (TK2), which encodes a ubiquitous mitochondrial protein. To study the pathogenesis of TK2-deficiency, we generated mice harboring an H126N Tk2 mutation. Homozygous...

  5. Unbalanced Cylindrical Magnetron for Accelerating Cavities Coating

    CERN Document Server

    Rosaz, Guillaume; Calatroni, Sergio; Sublet, Alban; Tobarelli, Mauro

    2016-01-01

    We report in this paper the design and qualification of a cylindrical unbalanced magnetron source. The dedicated magnetic assemblies were simulated using a finite element model. A hall-effect magnetic probe was then used to characterize those assemblies and compared to the theoretical magnet profiles. These show a good agreement between the expected and actual values. the qualification of the different magnetic assemblies was then performed by measuring the ion flux density reaching the surface of the sample to be coated using a commercial retarding field energy analyzer. The strongest unbalanced configuration shows an increase from 0.016A.cm^-2 to 0.074A.cm^-2 of the ion flux density reaching the sample surface compared to the standard balanced configuration for a pressure 5.10^-3 mbar and a plasma source power of 300W.

  6. Effective Loss Minimization and Allocation of Unbalanced Distribution Network

    Directory of Open Access Journals (Sweden)

    Manvir Kaur

    2017-11-01

    Full Text Available An efficient distribution network must be able to supply power with good voltage profile. The main objective of the proposed work is to allocate losses of the unbalanced distribution network by the firefly algorithm in regulated and deregulated environments before and after loss minimization. Reconfiguration is one of the methods for loss reduction of unbalanced distribution network. Further, optimal placement of distributed generation and capacitor in the reconfigured unbalanced distribution network can further reduce the loss. The results of reconfigured unbalanced distribution network in regulated environment have already been reported. In this paper reconfiguration of an unbalanced distribution network in a deregulated environment is also carried out using an established Fuzzy Firefly algorithm. Loss sensitivity factor of unbalanced distribution networks is used to get the appropriate location of distributed generation and capacitor to be placed in the unbalanced distribution network. Their ratings have been found out by using bacteria foraging optimization algorithm (BFOA. The suggested loss allocation method using Firefly algorithm is implemented at first on 13 node unbalanced distribution network to check the performance of the proposed loss allocation method when compared to other available method. Finally the proposed method has been implemented on 25 node unbalanced distribution network. Both of the implementations are carried out under MATLAB environment.

  7. The Unbalanced Linguistic Aggregation Operator in Group Decision Making

    Directory of Open Access Journals (Sweden)

    Li Zou

    2012-01-01

    Full Text Available Many linguistic aggregation methods have been proposed and applied in the linguistic decision-making problems. In practice, experts need to assess a number of values in a side of reference domain higher than in the other one; that is, experts use unbalanced linguistic values to express their evaluation for problems. In this paper, we propose a new linguistic aggregation operator to deal with unbalanced linguistic values in group decision making, we adopt 2-tuple representation model of linguistic values and linguistic hierarchies to express unbalanced linguistic values, and moreover, we present the unbalanced linguistic ordered weighted geometric operator to aggregate unbalanced linguistic evaluation values; a comparison example is given to show the advantage of our method.

  8. Cash pooling

    OpenAIRE

    Lozovaya, Karina

    2009-01-01

    This work makes a mention of cash management. At next chapter describes two most known theoretical models of cash management -- Baumol Model and Miller-Orr Model. Principal part of work is about cash pooling, types of cash pooling, cash pooling at Czech Republic and influence of cash pooling over accounting and taxes.

  9. Exciting Pools

    Science.gov (United States)

    Wright, Bradford L.

    1975-01-01

    Advocates the creation of swimming pool oscillations as part of a general investigation of mechanical oscillations. Presents the equations, procedure for deriving the slosh modes, and methods of period estimation for exciting swimming pool oscillations. (GS)

  10. Unbalanced Regressions and the Predictive Equation

    DEFF Research Database (Denmark)

    Osterrieder, Daniela; Ventosa-Santaulària, Daniel; Vera-Valdés, J. Eduardo

    Predictive return regressions with persistent regressors are typically plagued by (asymptotically) biased/inconsistent estimates of the slope, non-standard or potentially even spurious statistical inference, and regression unbalancedness. We alleviate the problem of unbalancedness in the theoreti......Predictive return regressions with persistent regressors are typically plagued by (asymptotically) biased/inconsistent estimates of the slope, non-standard or potentially even spurious statistical inference, and regression unbalancedness. We alleviate the problem of unbalancedness...... in the theoretical predictive equation by suggesting a data generating process, where returns are generated as linear functions of a lagged latent I(0) risk process. The observed predictor is a function of this latent I(0) process, but it is corrupted by a fractionally integrated noise. Such a process may arise due...... to aggregation or unexpected level shifts. In this setup, the practitioner estimates a misspecified, unbalanced, and endogenous predictive regression. We show that the OLS estimate of this regression is inconsistent, but standard inference is possible. To obtain a consistent slope estimate, we then suggest...

  11. A method for unbalanced transportation problems in fuzzy ...

    Indian Academy of Sciences (India)

    Among linear programming problems, the transportation problem is very popular. ... Therefore, Zadeh (1965) introduced the concept of fuzzy numbers. ... While solving unbalanced transportation problems we come across two type of cases.

  12. Influence of unbalanced voltages on the movement of metallic ...

    Indian Academy of Sciences (India)

    Simulation is carried out on particle movement with balanced and unbalanced voltages and the ... dust, meteorological difficulties and safety. Hence ... work reported deals with the charge acquired by the particle due to macroscopic field at the.

  13. Control Strategy for Microgrid Inverter under Unbalanced Grid Voltage Conditions

    DEFF Research Database (Denmark)

    Guo, Xiaoqiang; Liu, Wenzhao; Zhang, X.

    2014-01-01

    This paper presents the theoretical analysis of the inherent reason of current harmonic and power oscillation phenomena in case of operating the microgrid inverter under unbalanced grid voltage conditions. In order to flexibly control the current harmonic and power oscillation, a new stationary...... inverter. Finally, the performance evaluation tests are carried out under unbalanced grid voltage conditions. Results verify the effectiveness of the propose method....

  14. Unbalanced atrioventricular septal defect: definition and decision making.

    Science.gov (United States)

    Overman, David M; Baffa, Jeanne M; Cohen, Meryl S; Mertens, Luc; Gremmels, David B; Jegatheeswaram, Anusha; McCrindle, Brian W; Blackstone, Eugene H; Morell, Victor O; Caldarone, Christopher; Williams, William G; Pizarro, Christian

    2010-04-01

    Unbalanced atrioventricular septal defect is an uncommon lesion with widely varying anatomic manifestations. When unbalance is severe, diagnosis and treatment is straightforward, directed toward single-ventricle palliation. Milder forms, however, pose a challenge to current diagnostic and therapeutic approaches. The transition from anatomies that are capable of sustaining biventricular physiology to those that cannot is obscure, resulting in uneven application of surgical strategy and excess mortality. Imprecise assessments of ventricular competence have dominated clinical decision making in this regard. Malalignment of the atrioventricular junction and its attendant derangement of inflow physiology is a critical factor in determining the feasibility of biventricular repair in the setting of unbalanced atrioventricular septal defect. The atrioventricular valve index accurately identifies unbalanced atrioventricular septal defect and also brings into focus a zone of transition from anatomies that can support a biventricular end state and those that cannot.

  15. Dynamics Analysis of Unbalanced Motorized Spindles Supported on Ball Bearings

    Directory of Open Access Journals (Sweden)

    Junfeng Liu

    2016-01-01

    Full Text Available This paper presents an improved dynamic model for unbalanced high speed motorized spindles. The proposed model includes a Hertz contact force model which takes into the internal clearance and an unbalanced electromagnetic force model based on the energy of the air magnetic field. The nonlinear characteristic of the model is analysed by Lyapunov stability theory and numerical analysis to study the dynamic properties of the spindle system. Finally, a dynamic operating test is carried out on a DX100A-24000/20-type motorized spindle. The good agreement between the numerical solutions and the experimental data indicates that the proposed model is capable of accurately predicting the dynamic properties of motorized spindles. The influence of the unbalanced magnetic force on the system is studied, and the sensitivities of the system parameters to the critical speed of the system are obtained. These conclusions are useful for the dynamic design of high speed motorized spindles.

  16. Sequential Service Restoration for Unbalanced Distribution Systems and Microgrids

    International Nuclear Information System (INIS)

    Chen, Bo; Chen, Chen; Wang, Jianhui; Butler-Purry, Karen L.

    2017-01-01

    The resilience and reliability of modern power systems are threatened by increasingly severe weather events and cyber-physical security events. An effective restoration methodology is desired to optimally integrate emerging smart grid technologies and pave the way for developing self-healing smart grids. In this paper, a sequential service restoration (SSR) framework is proposed to generate restoration solutions for distribution systems and microgrids in the event of large-scale power outages. The restoration solution contains a sequence of control actions that properly coordinate switches, distributed generators, and switchable loads to form multiple isolated microgrids. The SSR can be applied for three-phase unbalanced distribution systems and microgrids and can adapt to various operation conditions. Mathematical models are introduced for three-phase unbalanced power flow, voltage regulators, transformers, and loads. Furthermore, the SSR problem is formulated as a mixed-integer linear programming model, and its effectiveness is evaluated via the modified IEEE 123 node test feeder.

  17. Pool scrubbing

    International Nuclear Information System (INIS)

    Lopez-Jimenez, J.; Herranz, J.; Escudero, M.J.; Espigares, M.M.; Peyres, V.; Polo, J.; Kortz, Ch.; Koch, M.K.; Brockmeier, U.; Unger, H.; Dutton, L.M.C.; Smedley, Ch.; Trow, W.; Jones, A.V.; Bonanni, E.; Calvo, M.; Alonso, A.

    1996-12-01

    The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

  18. Three-Phase Harmonic Analysis Method for Unbalanced Distribution Systems

    Directory of Open Access Journals (Sweden)

    Jen-Hao Teng

    2014-01-01

    Full Text Available Due to the unbalanced features of distribution systems, a three-phase harmonic analysis method is essential to accurately analyze the harmonic impact on distribution systems. Moreover, harmonic analysis is the basic tool for harmonic filter design and harmonic resonance mitigation; therefore, the computational performance should also be efficient. An accurate and efficient three-phase harmonic analysis method for unbalanced distribution systems is proposed in this paper. The variations of bus voltages, bus current injections and branch currents affected by harmonic current injections can be analyzed by two relationship matrices developed from the topological characteristics of distribution systems. Some useful formulas are then derived to solve the three-phase harmonic propagation problem. After the harmonic propagation for each harmonic order is calculated, the total harmonic distortion (THD for bus voltages can be calculated accordingly. The proposed method has better computational performance, since the time-consuming full admittance matrix inverse employed by the commonly-used harmonic analysis methods is not necessary in the solution procedure. In addition, the proposed method can provide novel viewpoints in calculating the branch currents and bus voltages under harmonic pollution which are vital for harmonic filter design. Test results demonstrate the effectiveness and efficiency of the proposed method.

  19. Precise derating of three phase induction motors with unbalanced voltages

    International Nuclear Information System (INIS)

    Faiz, Jawad; Ebrahimpour, H.

    2007-01-01

    Performance analysis of three phase induction motors under supply voltage unbalance conditions is normally conducted using the well-known symmetrical components analysis. In this analysis, the voltage unbalance level at the terminals of the machine is assessed by means of the NEMA or IEC definitions. Both definitions lead to a relatively large error in predicting the performance of a machine. A method has recently been proposed in which, in addition to the voltage unbalance factor (VUF), the phase angle has been taken into account in the analysis. This means that the voltage unbalance factor is regarded as a complex value. This paper shows that although the use of the complex VUF reduces the computational error considerably, it is still high. This is proven by evaluating the derating factor of a three phase induction motor. A method is introduced to determine the derating factor precisely using the complex unbalance factor for an induction motor operating under any unbalanced supply condition. A practical case for derating of a typical three phase squirrel cage induction motor supplied by an unbalanced voltage is studied in the paper

  20. A Three-Phase Microgrid Restoration Model Considering Unbalanced Operation of Distributed Generation

    International Nuclear Information System (INIS)

    Wang, Zeyu; Wang, Jianhui; Chen, Chen

    2016-01-01

    Recent severe outages highlight the urgency of improving grid resiliency in the U.S. Microgrid formation schemes are proposed to restore critical loads after outages occur. Most distribution networks have unbalanced configurations that are not represented in sufficient detail by single-phase models. This study provides a microgrid formation plan that adopts a three-phase network model to represent unbalanced distribution networks. The problem formulation has a quadratic objective function with mixed-integer linear constraints. The three-phase network model enables us to examine the three-phase power outputs of distributed generators (DGs), preventing unbalanced operation that might trip DGs. Because the DG unbalanced operation constraint is non-convex, an iterative process is presented that checks whether the unbalanced operation limits for DGs are satisfied after each iteration of optimization. We also develop a relatively conservative linear approximation on the unbalanced operation constraint to handle larger networks. Compared with the iterative solution process, the conservative linear approximation is able to accelerate the solution process at the cost of sacrificing optimality to a limited extent. Simulation in the IEEE 34 node and IEEE 123 test feeders indicate that the proposed method yields more practical microgrid formations results. In addition, this paper explores the coordinated operation of DGs and energy storage (ES) installations. The unbalanced three-phase outputs of ESs combined with the relatively balanced outputs of DGs could supply unbalanced loads. In conclusion, the case study also validates the DG-ES coordination.

  1. Research on three-phase unbalanced distribution network reconfiguration strategy

    Science.gov (United States)

    Hu, Shuang; Li, Ke-Jun; Xu, Yanshun; Liu, Zhijie; Guo, Jing; Wang, Zhuodi

    2017-01-01

    With the development of social economy, the loads installed in the distribution network become more and more complex which may cause the three-phase unbalance problems. This paper proposes an optimal reconfiguration approach based on mixed integer quadric programming (MIQP) method to address the three-phase unbalance problem. It aims to minimize the total network losses of the system. By using several square constraints to substitute the circular constraint, the original optimization problem is linearized and converted into a mixed-integer linear programming (MILP) model. Then this MILP problem is solved in general algebraic model system (GAMS) software using CPLEX solver. The additional losses caused by three-phase unbalanced are also considered. An IEEE 34 nodes test system is used to demonstrate the feasibility and effectiveness of the proposed method. The results show that the losses and the voltage violation mitigation in the network can be reduced significantly.

  2. Three-Phase Unbalanced Load Flow Tool for Distribution Networks

    DEFF Research Database (Denmark)

    Demirok, Erhan; Kjær, Søren Bækhøj; Sera, Dezso

    2012-01-01

    This work develops a three-phase unbalanced load flow tool tailored for radial distribution networks based on Matlab®. The tool can be used to assess steady-state voltage variations, thermal limits of grid components and power losses in radial MV-LV networks with photovoltaic (PV) generators where...... most of the systems are single phase. New ancillary service such as static reactive power support by PV inverters can be also merged together with the load flow solution tool and thus, the impact of the various reactive power control strategies on the steady-state grid operation can be simply...... investigated. Performance of the load flow solution tool in the sense of resulting bus voltage magnitudes is compared and validated with IEEE 13-bus test feeder....

  3. Visualization in mechanics: the dynamics of an unbalanced roller

    Science.gov (United States)

    Cumber, Peter S.

    2017-04-01

    It is well known that mechanical engineering students often find mechanics a difficult area to grasp. This article describes a system of equations describing the motion of a balanced and an unbalanced roller constrained by a pivot arm. A wide range of dynamics can be simulated with the model. The equations of motion are embedded in a graphical user interface for its numerical solution in MATLAB. This allows a student's focus to be on the influence of different parameters on the system dynamics. The simulation tool can be used as a dynamics demonstrator in a lecture or as an educational tool driven by the imagination of the student. By way of demonstration the simulation tool has been applied to a range of roller-pivot arm configurations. In addition, approximations to the equations of motion are explored and a second-order model is shown to be accurate for a limited range of parameters.

  4. Hawaii ESI: POOLS (Anchialine Pool Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

  5. Load mitigation of unbalanced wind turbines using PI-R individual pitch control

    DEFF Research Database (Denmark)

    Zhang, Yunqian; Cheng, Ming; Chen, Zhe

    2015-01-01

    This study discusses the load mitigation of unbalanced wind turbines, including balanced and unbalanced loads. Regarding the wind turbine load reduction, it has been shown that individual pitch control (IPC) is more promising in comparison with collective pitch control. However, wind turbine......) controller and two resonant (R) compensators is presented. The PI-R regulator is implemented in the hub reference frame to reduce both the balanced and unbalanced loads of the turbine. The wind turbine code FAST (fatigue, aerodynamics, structures and turbulence) is used for the wind turbine load modelling....... The simulations are conducted on the NREL upwind 1.5 MW wind turbine model. Elimination of both the balanced and unbalanced loads of the wind turbine has been achieved, so that PI-R IPC is demonstrated as an effective means for load mitigation of unbalanced wind turbines....

  6. Aspects of DNA repair and nucleotide pool imbalance

    Energy Technology Data Exchange (ETDEWEB)

    Holliday, R.

    1985-01-01

    Evidence that optimum repair depends on adequate pools of deoxynucleotide triphosphates (dNTPs) comes from the study of pyrimidine auxotrophs of Ustilago maydis. These strains are sensitive to UV light and X-rays, and for pyr1-1 it has been shown that the intracellular concentration of dTTP is reduced about 7-fold. The survival curve of pyr1-1 after UV-treatment, and split dose experiments with wild-type cells, provide evidence for an inducible repair mechanism, which probably depends on genetic recombination. Although inducible repair saves cellular resources, it has the disadvantage of becoming ineffective at doses which are high enough to inactivate the repressed structural gene(s) for repair enzymes. It is clear that a wide variety of repair mechanisms have evolved to remove lesions which arise either spontaneously or as a result of damage from external agents. Nevertheless, it would be incorrect to assume that all species require all possible pathways of repair. It is now well established that the accuracy of DNA and protein synthesis depends on proof-reading or editing mechanisms. Optimum accuracy levels will evolve from the balance between error avoidance in macromolecular synthesis and physiological efficiency in growth and propagation.

  7. Analysis on the roundness of bulb turbine generator based on the unbalanced magnetic

    International Nuclear Information System (INIS)

    Li, Z G; Yang, F Y; Chen, J H; Si, G L

    2012-01-01

    Because of design, manufacture, installation and operation, there are some relatively eccentric in bulb tubular turbine units under operating condition. It easily caused uneven air gap, unbalanced magnetic field, unbalanced magnetic pull and torque. It could also increase the bending and torsion vibration of generator,at the same time, the roundness of stator and rotor would be aggravated which often caused by accidents such as generator sweep chamber. In this paper, basing on the design, installation and operation experience, the reasons of the unbalanced magnetic pull, mechanism and operation research were analyzed by theoretical calculation and the prototype test.

  8. Superconducting niobium nitride films deposited by unbalanced magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Olaya, J.J. [Departamento de Ingenieria Mecanica y Mecatronica, Universidad Nacional de Colombia, Ciudad Universitaria, Carrera 30 Numero 45-03, Bogota (Colombia); Huerta, L. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Circuito exterior s/n, CU Coyoacan, Mexico D.F. 04510 (Mexico); Rodil, S.E. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Circuito exterior s/n, CU Coyoacan, Mexico D.F. 04510 (Mexico)], E-mail: ser42@iim.unam.mx; Escamilla, R. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Circuito exterior s/n, CU Coyoacan, Mexico D.F. 04510 (Mexico)

    2008-10-01

    Niobium nitride (NbN) thin films were deposited under different configurations of the magnetic field using a magnetron sputtering system. The magnetic field configuration varied from balanced to unbalanced leading to different growth conditions and film properties. The aim of the paper was to identify correlations between deposition conditions, film properties and the electrical properties, specially the superconductive critical temperature (T{sub C}). The results suggested that there is a critical deposition condition, having an optimum ion-atom arrival ratio that promotes a well ordered and textured nanocrystalline structure (cubic phase) with the minimum residual stress and only under this condition a high critical temperature (16K) was obtained. Lower T{sub C} values around 12K were obtained for the NbN samples having a lower degree of structural perfection and texture, and a larger fraction of intergranular voids. On the other hand, analysis of valence-band spectra showed that the contribution of the Nb 4d states remained essentially constant while the higher T{sub C} was correlated to a higher contribution of the N 2p states.

  9. Superconducting niobium nitride films deposited by unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Olaya, J.J.; Huerta, L.; Rodil, S.E.; Escamilla, R.

    2008-01-01

    Niobium nitride (NbN) thin films were deposited under different configurations of the magnetic field using a magnetron sputtering system. The magnetic field configuration varied from balanced to unbalanced leading to different growth conditions and film properties. The aim of the paper was to identify correlations between deposition conditions, film properties and the electrical properties, specially the superconductive critical temperature (T C ). The results suggested that there is a critical deposition condition, having an optimum ion-atom arrival ratio that promotes a well ordered and textured nanocrystalline structure (cubic phase) with the minimum residual stress and only under this condition a high critical temperature (16K) was obtained. Lower T C values around 12K were obtained for the NbN samples having a lower degree of structural perfection and texture, and a larger fraction of intergranular voids. On the other hand, analysis of valence-band spectra showed that the contribution of the Nb 4d states remained essentially constant while the higher T C was correlated to a higher contribution of the N 2p states

  10. Research on a Compound Control Strategy of Three-Phase Inverter for Unbalanced Loads

    Directory of Open Access Journals (Sweden)

    Yue Gaili

    2017-01-01

    Full Text Available To solve the problem of unbalanced output voltage of inverter under three-phase unbalanced load. In this paper, the main circuit topology using three-phase three-wire inverter topology. Established the mathematical model in several different coordinate system of the three-phase inverter. A compound control method is proposed by combining voltage current dual loop control method and repetitive control method, The control method is realized in three - phase 400 Hz inverter, and can meet the demand of unbalanced load to inverter, the reliability of the inverter circuit is improved. At the end of this paper, Matlab simulation analysis and experimental results are given, it is proved that the composite control method designed in this paper has a strong ability of unbalanced load.

  11. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  12. Swimming pool granuloma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

  13. Dynamic Models of Instruments Using Rotating Unbalanced Masses

    Science.gov (United States)

    Hung, John Y.; Gallaspy, Jason M.; Bishop, Carlee A.

    1998-01-01

    The motion of telescopes, satellites, and other flight bodies have been controlled by various means in the past. For example, gimbal mounted devices can use electric motors to produce pointing and scanning motions. Reaction wheels, control moment gyros, and propellant-charged reaction jets are other technologies that have also been used. Each of these methods has its advantages, but all actuator systems used in a flight environment face the challenges of minimizing weight, reducing energy consumption, and maximizing reliability. Recently, Polites invented and patented the Rotating Unbalanced Mass (RUM) device as a means for generation scanning motion on flight experiments. RUM devices together with traditional servomechanisms have been successfully used to generate various scanning motions: linear, raster, and circular. The basic principle can be described: A RUM rotating at constant angular velocity exerts a cyclic centrifugal force on the instrument or main body, thus producing a periodic scanning motion. A system of RUM devices exerts no reaction forces on the main body, requires very little energy to rotate the RUMS, and is simple to construct. These are significant advantages over electric motors, reaction wheels, and control moment gyroscopes. Although the RUM device very easily produces scanning motion, an auxiliary control system has been required to maintain the proper orientation, or pointing of the main body. It has been suggested that RUM devices can be used to control pointing dynamics, as well as generate the desired periodic scanning motion. The idea is that the RUM velocity will not be kept constant, but will vary over the period of one RUM rotation. The thought is that the changing angular velocity produces a centrifugal force having time-varying magnitude and direction. The scope of this ongoing research project is to study the pointing control concept, and recommend a direction of study for advanced pointing control using only RUM devices. This

  14. Design of Solar PV Cell Based Inverter for Unbalanced and Distorted Industrial Loads

    Directory of Open Access Journals (Sweden)

    Naga Ananth D

    2015-04-01

    Full Text Available PV cell is getting importance in low and medium power generation due to easy installation, low maintenance and subsidies in price from respective nation. Most of the loads in distribution system are unbalanced and distorted, due to which there will be unbalanced voltage and current occur at load and may disturb its overall performance. Due to these loads voltage unbalance, distorted voltage and current and variable power factors in each phase can be observed. An efficient algorithm to mitigate unbalanced and distorted load and source voltage and current in solar photo voltaic (PV inverter for isolated load system was considered. This solar PV system can be applicable to remote located industrial loads like heating, welding and small arc furnace type distorted loads and also for unbalanced loads. The PV inverter is designed such that it will maintain nearly constant voltage magnitude and can mitigate harmonics in voltage and current near the load terminals. A MATLAB/ SIMULINK based solar PV inverter was simulated and results are compared with standard AC three phase grid connected system. The proposed shows that the inverter is having very less voltage and current harmonic content and can maintain nearly constant voltage profile for highly unbalanced system.

  15. Solar swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

  16. Empirical Statistical Power for Testing Multilocus Genotypic Effects under Unbalanced Designs Using a Gibbs Sampler

    Directory of Open Access Journals (Sweden)

    Chaeyoung Lee

    2012-11-01

    Full Text Available Epistasis that may explain a large portion of the phenotypic variation for complex economic traits of animals has been ignored in many genetic association studies. A Baysian method was introduced to draw inferences about multilocus genotypic effects based on their marginal posterior distributions by a Gibbs sampler. A simulation study was conducted to provide statistical powers under various unbalanced designs by using this method. Data were simulated by combined designs of number of loci, within genotype variance, and sample size in unbalanced designs with or without null combined genotype cells. Mean empirical statistical power was estimated for testing posterior mean estimate of combined genotype effect. A practical example for obtaining empirical statistical power estimates with a given sample size was provided under unbalanced designs. The empirical statistical powers would be useful for determining an optimal design when interactive associations of multiple loci with complex phenotypes were examined.

  17. Mitigation of Unbalanced Voltage Sags and Voltage Unbalance in CIGRE Low Voltage Distribution Network

    DEFF Research Database (Denmark)

    Mustafa, Ghullam; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    Any problem with voltage in a power network is undesirable as it aggravates the quality of the power. Power electronic devices such as Voltage Source Converter (VSC) based Static Synchronous Compensator (STATCOM) etc. can be used to mitigate the voltage problems in the distribution system...... to unbalanced faults. The compensation of unbalanced voltage sags and voltage unbalance in the CIGRE distribution network is done by using the four STATCOM compensators already existing in the test grid. The simulations are carried out in DIgSILENT power factory software version 15.0........ The voltage problems dealt with in this paper are to show how to mitigate unbalanced voltage sags and voltage unbalance in the CIGRE Low Voltage (LV) test network and net-works like this. The voltage unbalances, for the tested cases in the CIGRE LV test network are mainly due to single phase loads and due...

  18. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  19. A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing.

    Science.gov (United States)

    Wang, Zhaocai; Pu, Jun; Cao, Liling; Tan, Jian

    2015-10-23

    The unbalanced assignment problem (UAP) is to optimally resolve the problem of assigning n jobs to m individuals (m applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn) time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation.

  20. Enhanced Decoupled Double Synchronous Reference Frame Current Controller for Unbalanced Grid-Voltage Conditions

    DEFF Research Database (Denmark)

    Reyes, M.; Rodriguez, Pedro; Vazquez, S.

    2012-01-01

    . In these codes, the injection of positive- and negative-sequence current components becomes necessary for fulfilling, among others, the low-voltage ride-through requirements during balanced and unbalanced grid faults. However, the performance of classical dq current controllers, applied to power converters......, under unbalanced grid-voltage conditions is highly deficient, due to the unavoidable appearance of current oscillations. This paper analyzes the performance of the double synchronous reference frame controller and improves its structure by adding a decoupling network for estimating and compensating...

  1. A parametric study on unbalanced three phase islanded microgrids with inverter interfaced units

    DEFF Research Database (Denmark)

    Sanseverino, Eleonora Riva; Quang, Ninh Nguyen; Zizzo, Gaetano

    2013-01-01

    In this paper, the solution of the power flow for unbalanced three phase microgrids systems is proposed. The study aims at the integration of inverter interfaced units using the control law used for primary voltage and frequency regulation, so as to take into account possible small variations...... of these parameters to account for sudden load changes. The proposed study deals with unbalanced systems which is the typical case of small distribution systems and shows how the power losses term varies as the regulators parameters vary as well, thus showing that these are sensitive parameters that could have...

  2. Improved delayed signal cancellation-based SRF-PLL for unbalanced grid

    DEFF Research Database (Denmark)

    Messo, Tuomas; Sihvo, Jussi; Yang, Dongsheng

    2017-01-01

    Problems with power quality in the grid have gained a lot of attention recently due to rapid increase in the amount of grid-connected power converters. The converter should produce sinusoidal currents also during abnormal conditions, such as unbalanced grid voltages. Several methods, like...... the delayed signal cancellation-based method (DSC), have been proposed to alleviate the detrimental effect of unbalance. This paper proposes an improvement to a delayed signal cancellation based synchronization algorithm for unbalanced grids. The proposed PLL structure employs only half of the delay required...

  3. Unbalanced voltage faults: the impact on structural loads of doubly fed asynchronous generator wind turbines

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio; Cutululis, Nicolaos Antonio; Hansen, Anca Daniela

    2014-01-01

    This paper investigates the impact that unbalanced voltage faults have on wind turbine structural loads. In such cases, electromagnetic torque oscillations occur at two times the supply voltage frequency. The objectives of this work are to quantify wind turbine structural loads induced...... by unbalanced voltage faults relative to those during normal operation; and to evaluate the potential for reducing structural loads with the control of the generator. The method applied is integrated dynamic analysis. Namely, dynamic analysis with models that consider the most important aeroelastic, electrical...

  4. Flexible Control Strategy for Grid-Connected Inverter under Unbalanced Grid Faults without PLL

    DEFF Research Database (Denmark)

    Guo, Xiaoqiang; Liu, W.; Zhang, X.

    2015-01-01

    Power oscillation and current quality are the important performance targets for the grid-connected inverter under unbalanced grid faults. Firstly, the inherent reason for the current harmonic and power oscillation of the inverter is discussed with a quantitative analysis. Secondly, a new control...... strategy is proposed to achieve the coordinate control of power and current quality without the need for a phase-locked loop or voltage/current positive/negative sequence extraction calculation. Finally, the experimental tests are conducted under unbalanced grid faults, and the results verify...

  5. Spent fuel storage pool

    International Nuclear Information System (INIS)

    Murakami, Naoshi.

    1996-01-01

    Fences are disposed to a fuel exchange floor surrounding the upper surface of a fuel pool for preventing overflow of pool water. The fences comprise a plurality of flat boards arranged in parallel with each other in the longitudinal direction while being vertically inclined, and slits are disposed between the boards for looking down the pool. Further, the fences comprise wide boards and are constituted so as to be laid horizontally on the fuel exchange floor in a normal state and uprisen by means of the signals from an earthquake sensing device. Even if pool water is overflow from the fuel pool by the vibrations occurred upon earthquake and flown out to the floor of the fuel exchange floor, the overflow from the fuel exchange floor is prevented by the fences. An operator who monitors the fuel pool can observe the inside of the fuel pool through the slits formed to the fences during normal operation. The fences act as resistance against overflowing water upon occurrence of an earthquake thereby capable of reducing the overflowing amount of water due to the vibrations of pool water. The effect of preventing overflowing water can be enhanced. (N.H.)

  6. Collaborative Car Pooling System

    OpenAIRE

    João Ferreira; Paulo Trigo; Porfírio Filipe

    2009-01-01

    This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

  7. Balance control of grid currents for UPQC under unbalanced loads based on matching-ratio compensation algorithm

    DEFF Research Database (Denmark)

    Zhao, Xiaojun; Zhang, Chunjiang; Chai, Xiuhui

    2018-01-01

    In three-phase four-wire systems, unbalanced loads can cause grid currents to be unbalanced, and this may cause the neutral point potential on the grid side to shift. The neutral point potential shift will worsen the control precision as well as the performance of the threephase four-wire unified...... fluctuations, and elaborates the interaction between unbalanced grid currents and DC bus voltage fluctuations; two control strategies of UPQC under three-phase stationary coordinate based on the MCA are given, and finally, the feasibility and effectiveness of the proposed control strategy are verified...... power quality conditioner (UPQC), and it also leads to unbalanced three-phase output voltage, even causing damage to electric equipment. To deal with unbalanced loads, this paper proposes a matching-ratio compensation algorithm (MCA) for the fundamental active component of load currents...

  8. Design and analysis of active power control strategies for distributed generation inverters under unbalanced grid faults

    NARCIS (Netherlands)

    Wang, F.; Duarte, J.L.; Hendrix, M.A.M.

    2010-01-01

    Distributed power generation systems are expected to deliver active power into the grid and support it without interruption during unbalanced grid faults. Aiming to provide grid-interfacing inverters the flexibility to adapt to the coming change of grid requirements, an optimised active power

  9. Unbalanced Impedance of the Aperture Coils of Some LHC Main Dipole Magnets

    NARCIS (Netherlands)

    Ravaioli, Emanuele; Verweij, A.P.; ten Kate, Herman H.J.

    2013-01-01

    During the Large Hadron Collider operation in 2010 and 2011, it was observed that about 50% of the main dipole magnets exhibiting two apertures showed unbalanced dynamic-impedance behavior not well understood. When a main dipole circuit is switched off, voltage waves with a frequency of 28 Hz travel

  10. Revised sequence components power system models for unbalanced power system studies

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Akher, M. [Tunku Abdul Rahman Univ., Kuala Lumpur (Malaysia); Nor, K.-M. [Univ. of Technology Malaysia, Johor (Malaysia); Rashid, A.H.A. [Univ. of Malaya, Kuala Lumpur (Malaysia)

    2007-07-01

    The principle method of analysis using positive, negative, and zero-sequence networks has been used to examine the balanced power system under both balanced and unbalanced loading conditions. The significant advantage of the sequence networks is that the sequence networks become entirely uncoupled in the case of balanced three-phase power systems. The uncoupled sequence networks then can be solved in independent way such as in fault calculation programs. However, the hypothesis of balanced power systems cannot be considered in many cases due to untransposed transmission lines; multiphase line segments in a distribution power system; or transformer phase shifts which cannot be incorporated in the existing models. A revised sequence decoupled power system models for analyzing unbalanced power systems based on symmetrical networks was presented in this paper. These models included synchronous machines, transformers, transmission lines, and voltage regulators. The models were derived from their counterpart's models in phase coordinates frame of reference. In these models, the three sequence networks were fully decoupled with a three-phase coordinates features such as transformer phase shifts and transmission line coupling. The proposed models were used to develop an unbalanced power-flow program for analyzing both balanced and unbalanced networks. The power flow solution was identical to results obtained from a full phase coordinate three-phase power-flow program. 11 refs., 3 tabs.

  11. High Order Sliding Mode Control of Doubly-fed Induction Generator under Unbalanced Grid Faults

    DEFF Research Database (Denmark)

    Zhu, Rongwu; Chen, Zhe; Wu, Xiaojie

    2013-01-01

    This paper deals with a doubly-fed induction generator-based (DFIG) wind turbine system under grid fault conditions such as: unbalanced grid voltage, three-phase grid fault, using a high order sliding mode control (SMC). A second order sliding mode controller, which is robust with respect...

  12. A New Wind Turbine Generating System Model for Balanced and Unbalanced Distribution Systems Load Flow Analysis

    Directory of Open Access Journals (Sweden)

    Ahmet Koksoy

    2018-03-01

    Full Text Available Wind turbine generating systems (WTGSs, which are conventionally connected to high voltage transmission networks, have frequently been employed as distributed generation units in today’s distribution networks. In practice, the distribution networks always have unbalanced bus voltages and line currents due to uneven distribution of single or double phase loads over three phases and asymmetry of the lines, etc. Accordingly, in this study, for the load flow analysis of the distribution networks, Conventional Fixed speed Induction Generator (CFIG based WTGS, one of the most widely used WTGS types, is modelled under unbalanced voltage conditions. The Developed model has active and reactive power expressions in terms of induction machine impedance parameters, terminal voltages and input power. The validity of the Developed model is confirmed with the experimental results obtained in a test system. The results of the slip calculation based phase-domain model (SCP Model, which was previously proposed in the literature for CFIG based WTGSs under unbalanced voltages, are also given for the comparison. Finally, the Developed model and the SCP model are implemented in the load flow analysis of the IEEE 34 bus test system with the CFIG based WTGSs and unbalanced loads. Thus, it is clearly pointed out that the results of the load flow analysis implemented with both models are very close to each other, and the Developed model is computationally more efficient than the SCP model.

  13. 13 CFR 120.611 - Pools backing Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pools backing Pool Certificates. 120.611 Section 120.611 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Certificates § 120.611 Pools backing Pool Certificates. (a) Pool characteristics. As set...

  14. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  15. Swimming Pool Safety

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

  16. Vitamin D Pooling Project

    Science.gov (United States)

    The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

  17. Swimming pool special; Zwembadspecial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

  18. Analysis of PM Magnetization Field Effects on the Unbalanced Magnetic Forces due to Rotor Eccentricity in BLDC Motors

    Directory of Open Access Journals (Sweden)

    S. Mahdiuon-Rad

    2013-08-01

    Full Text Available This paper investigates both static and dynamic eccentricities in single phase brushless DC (BLDC motors and analyzes the effect of the PM magnetization field on unbalanced magnetic forces acting on the rotor. Three common types of PM magnetization field patterns including radial, parallel and sinusoidal magnetizations are considered. In both static and dynamic eccentricities, harmonic components of the unbalanced magnetic forces on the rotor are extracted and analyzed. Based on simulation results, the magnetization fields that produce the lowest and highest unbalanced magnetic forces are determined in rotor eccentricity conditions.

  19. Hysteresis current control technique of VSI for compensation of grid-connected unbalanced loads

    DEFF Research Database (Denmark)

    Pouresmaeil, Edris; Akorede, Mudathir Funsho; Montesinos-Miracle, Daniel

    2014-01-01

    interconnection issues that usually arise as DG units connect to the electric grid. The proposed strategy, implemented in Matlab/Simulink environment in different operating scenarios, provides compensation for active, reactive, unbalanced, and harmonic current components of grid-connected nonlinear unbalanced...... resources as they connect to the exiting power grid could provoke many power quality problems on the grid side. For this reason, due considerations must be given to power generation and safe running before DG units is actually integrated into the power grid. The main aim of this paper is to address the grid...... loads. The simulation results obtained in this study demonstrate the level of accuracy of the proposed technique, which ensure a balance in the overall grid phase currents, injection of maximum available power from DG resources to the grid, improvement of the utility grid power factor, and a reduction...

  20. Stand-Alone Microgrid Inverter Controller Design for Nonlinear, Unbalanced Load with Output Transformer

    Directory of Open Access Journals (Sweden)

    Jae-Uk Lim

    2018-04-01

    Full Text Available This paper proposes a technique that compensates for unbalance and nonlinearity in microgrid inverters with power transformers operating in stand-alone mode. When a microgrid inverter is operating in stand-alone mode, providing high-quality power is very important. When an unbalanced, nonlinear load is connected, zero sequence current and negative sequence current occur, which leads to an unbalanced output voltage. This paper examines why the zero sequence component occurs differently depending on the structure of a three-phase transformer connected to the inverter output terminal, and it proposes a method for controlling the zero sequence component. It also uses a resonant controller to remove the harmonics that correspond to the negative sequence component and the nonlinear component. The proposed elements were verified by a Powersim (PSIM simulation.

  1. Tracking performance of unbalanced QPSK demodulators. I - Biphase Costas loop with passive arm filters

    Science.gov (United States)

    Simon, M. K.; Alem, W. K.

    1978-01-01

    Unbalanced quadriphase-shift-keying (QPSK) is an attractive means for transmitting two digital data streams which in general have different average powers, data rates, and data formats. Previous analyses of the tracking performance of Costas loop demodulators of unbalanced QPSK have accounted only for the filtering effect produced by the loop's two arm filters on the equivalent additive noise perturbing the loop. When the bandwidth of these filters is selected on the basis of the order of the data rate, as is typical of optimum Costas loop design, the filtering degradations of the data modulations themselves and the cross-modulation noise produced by their multiplication in the loop often cannot be neglected. The purpose of this paper is to incorporate these additional filtering effects into the analysis. Many of the results obtained herein are in the form of closed-form expressions which can easily be evaluated numerically for design and performance prediction purposes.

  2. Grid-forming VSC control in four-wire systems with unbalanced nonlinear loads

    DEFF Research Database (Denmark)

    Lliuyacca, Ruben; Mauricioa, Juan M.; Gomez-Exposito, Antonio

    2017-01-01

    A grid-forming voltage source converter (VSC) is responsible to hold voltage and frequency in autonomous operation of isolated systems. In the presence of unbalanced loads, a fourth leg is added to provide current path for neutral currents. In this paper, a novel control scheme for a four-leg VSC...... feeding unbalanced linear and nonlinear loads is proposed. The control is based on two control blocks. A main control commands the switching sequence to the three-phase VSC ensuring balanced three-phase voltage at the output; and an independent control to the fourth leg drives neutral currents that might...... response during system disturbances and mitigation of harmonics when nonlinear loads are present. Simulations and experimental results are presented to verify the performance of the proposed control strategy....

  3. Power Controllability of Three-phase Converter with Unbalanced AC Source

    DEFF Research Database (Denmark)

    Ma, Ke; Liserre, Marco; Blaabjerg, Frede

    2013-01-01

    Three-phase DC-AC power converters suffer from power oscillation and overcurrentt problems in case of unbalanced AC source voltage that can be caused by grid/generator faults. Existing solutions to handle these problems are properly selecting and controlling the positive and negative sequence...... currents. In this work a new series of control strategies which utilize the zero-sequence components are proposed to enhance the power control ability under this adverse conditions. It is concluded that by introducing proper zero sequence current controls and corresponding circuit configurations, the power...... converter can enable more flexible control targets, achieving better performances in the delivered power and load current when suffering from unbalanced AC sources....

  4. Power Controllability of Three-phase Converter with Unbalanced AC Source

    DEFF Research Database (Denmark)

    Ma, Ke; Chen, Wenjie; Liserre, Marco

    2015-01-01

    Three-phase DC-AC power converters suffer from power oscillation and overcurrent problems in case of unbalanced AC source voltage that can be caused by grid/generator faults. Existing solutions to handle these problems are properly selecting and controlling the positive and negative sequence...... currents. In this work a new series of control strategies which utilize the zerosequence components are proposed to enhance the power control ability under this adverse condition. It is concluded that by introducing proper zero sequence current controls and corresponding circuit configurations, the power...... converter can enable more flexible control targets, achieving better performances in the delivered power and load current when suffering from unbalanced AC voltage....

  5. What drives health care expenditure?--Baumol's model of 'unbalanced growth' revisited.

    Science.gov (United States)

    Hartwig, Jochen

    2008-05-01

    The share of health care expenditure in GDP rises rapidly in virtually all OECD countries, causing increasing concern among politicians and the general public. Yet, economists have to date failed to reach an agreement on what the main determinants of this development are. This paper revisits Baumol's [Baumol, W.J., 1967. Macroeconomics of unbalanced growth: the anatomy of urban crisis. American Economic Review 57 (3), 415-426] model of 'unbalanced growth', showing that the latter offers a ready explanation for the observed inexorable rise in health care expenditure. The main implication of Baumol's model in this context is that health care expenditure is driven by wage increases in excess of productivity growth. This hypothesis is tested empirically using data from a panel of 19 OECD countries. Our tests yield robust evidence in favor of Baumol's theory.

  6. Synchronization of grid-connected renewable energy sources under highly distorted voltages and unbalanced grid faults

    DEFF Research Database (Denmark)

    Hadjidemetriou, Lenos; Kyriakides, Elias; Blaabjerg, Frede

    2013-01-01

    Renewable energy sources require accurate and appropriate performance not only under normal grid operation but also under abnormal and faulty grid conditions according to the modern grid codes. This paper proposes a novel phase-locked loop algorithm (MSHDC-PLL), which can enable the fast...... and dynamic synchronization of the interconnected renewable energy system under unbalanced grid faults and under highly harmonic distorted voltage. The outstanding performance of the suggested PLL is achieved by implementing an innovative multi-sequence/harmonic decoupling cell in order to dynamically cancel...... renewable energy systems. Therefore, the performance of the new PLL can increase the quality of the injected power under abnormal conditions and in addition enable the renewable energy systems to provide the appropriate support to the grid under balanced and unbalanced grid faults....

  7. Induced Unbalanced Linguistic Ordered Weighted Average and Its Application in Multiperson Decision Making

    Directory of Open Access Journals (Sweden)

    Lucas Marin

    2014-01-01

    Full Text Available Linguistic variables are very useful to evaluate alternatives in decision making problems because they provide a vocabulary in natural language rather than numbers. Some aggregation operators for linguistic variables force the use of a symmetric and uniformly distributed set of terms. The need to relax these conditions has recently been posited. This paper presents the induced unbalanced linguistic ordered weighted average (IULOWA operator. This operator can deal with a set of unbalanced linguistic terms that are represented using fuzzy sets. We propose a new order-inducing criterion based on the specificity and fuzziness of the linguistic terms. Different relevancies are given to the fuzzy values according to their uncertainty degree. To illustrate the behaviour of the precision-based IULOWA operator, we present an environmental assessment case study in which a multiperson multicriteria decision making model is applied.

  8. A Parallel Biological Optimization Algorithm to Solve the Unbalanced Assignment Problem Based on DNA Molecular Computing

    Directory of Open Access Journals (Sweden)

    Zhaocai Wang

    2015-10-01

    Full Text Available The unbalanced assignment problem (UAP is to optimally resolve the problem of assigning n jobs to m individuals (m < n, such that minimum cost or maximum profit obtained. It is a vitally important Non-deterministic Polynomial (NP complete problem in operation management and applied mathematics, having numerous real life applications. In this paper, we present a new parallel DNA algorithm for solving the unbalanced assignment problem using DNA molecular operations. We reasonably design flexible-length DNA strands representing different jobs and individuals, take appropriate steps, and get the solutions of the UAP in the proper length range and O(mn time. We extend the application of DNA molecular operations and simultaneity to simplify the complexity of the computation.

  9. Pool water cleaning facility

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

    1998-05-29

    Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

  10. Towards a time-domain modeling framework for small-signal analysis of unbalanced microgrids

    OpenAIRE

    Ojo, Y; Schiffer, JF

    2017-01-01

    Small-signal analysis is one of the most frequently used techniques to assess the operating conditions of power systems. Typically, this analysis is conducted by employing a phasor-based model of the power network derived under the assumption of balanced operating conditions. However, distribution networks and, amongst these, microgrids are often unbalanced. Hence, their analysis requires the development of tools and methods valid under such conditions. Motivated by this, we propose a modelin...

  11. A Fuzzy Linguistic Methodology to Deal With Unbalanced Linguistic Term Sets

    OpenAIRE

    Herrera, F.; Herrera-Viedma, Enrique; Martinez, L.

    2008-01-01

    Many real problems dealing with qualitative aspects use linguistic approaches to assess such aspects. In most of these problems, a uniform and symmetrical distribution of the linguistic term sets for linguistic modeling is assumed. However, there exist problems whose assessments need to be represented by means of unbalanced linguistic term sets, i.e., using term sets that are not uniformly and symmetrically distributed. The use of linguistic variables implies processes of computing with words...

  12. Ensemble Genetic Fuzzy Neuro Model Applied for the Emergency Medical Service via Unbalanced Data Evaluation

    Directory of Open Access Journals (Sweden)

    Muammar Sadrawi

    2018-03-01

    Full Text Available Equally partitioned data are essential for prediction. However, in some important cases, the data distribution is severely unbalanced. In this study, several algorithms are utilized to maximize the learning accuracy when dealing with a highly unbalanced dataset. A linguistic algorithm is applied to evaluate the input and output relationship, namely Fuzzy c-Means (FCM, which is applied as a clustering algorithm for the majority class to balance the minority class data from about 3 million cases. Each cluster is used to train several artificial neural network (ANN models. Different techniques are applied to generate an ensemble genetic fuzzy neuro model (EGFNM in order to select the models. The first ensemble technique, the intra-cluster EGFNM, works by evaluating the best combination from all the models generated by each cluster. Another ensemble technique is the inter-cluster model EGFNM, which is based on selecting the best model from each cluster. The accuracy of these techniques is evaluated using the receiver operating characteristic (ROC via its area under the curve (AUC. Results show that the AUC of the unbalanced data is 0.67974. The random cluster and best ANN single model have AUCs of 0.7177 and 0.72806, respectively. For the ensemble evaluations, the intra-cluster and the inter-cluster EGFNMs produce 0.7293 and 0.73038, respectively. In conclusion, this study achieved improved results by performing the EGFNM method compared with the unbalanced training. This study concludes that selecting several best models will produce a better result compared with all models combined.

  13. Effect of unbalanced voltage on windings temperature, operational life and load carrying capacity of induction machine

    Energy Technology Data Exchange (ETDEWEB)

    Gnacinski, P. [Gdynia Maritime University, Department of Ship Electrical Power Engineering, Morska Street 83, 81-225 Gdynia (Poland)

    2008-04-15

    This paper investigates the influence of the CVUF angle on the windings temperature rise and the derating factor of an induction machine supplied with unbalanced voltage. The effect of simultaneous voltage unbalance and harmonics on its operational life is analyzed as well. The results of calculations and experimental investigations are presented for two induction cage machines of rated power 3 and 5.5 kW. (author)

  14. Radio-frequency unbalanced M-Z interferometer for wavelength interrogation of fiber Bragg grating sensors.

    Science.gov (United States)

    Zhou, Jiaao; Xia, Li; Cheng, Rui; Wen, Yongqiang; Rohollahnejad, Jalal

    2016-01-15

    The optical unbalanced Mach-Zehnder interferometer (UMZI) has attracted significant interests for interrogation of FBG sensors owing to its excellent advantages in sensitivity, resolution, and demodulation speed. But this method is still limited to dynamic measurements due to its poor stability and reliability when used for quasi-static detections. Here, we propose for the first time, to the best of our knowledge, a radio-frequency unbalanced M-Z interferometer (RF-UMZI) for interrogation of FBG sensors, which, owing to its operation in an incoherent rather than a coherent regime, provides an ideal solution for the existing stability problem of the conventional UMZI, with remarkable features of adjustable resolution and potentially extremely high sensitivity. A dispersion compensation fiber (DCF) and single-mode fiber (SMF) with a small length difference are served as the two unbalanced arms of the RF interferometer. The induced differential chromatic dispersion transfers the wavelength shift of the FBG to the change of the RF phase difference between the two interferometric carriers, which ultimately leads to the variation of the RF signal intensity. An interrogation of a strain-turned FBG was accomplished and a maximum sensitivity of 0.00835  a.u./με was obtained, which can easily be further improved by more than two orders of magnitude through various fiber dispersion components. Finally, the stability of the interrogation was tested.

  15. Operation and control of a hybrid microgrid containing unbalanced and nonlinear loads

    Energy Technology Data Exchange (ETDEWEB)

    Shahnia, Farhad; Majumder, Ritwik; Ghosh, Arindam; Ledwich, Gerard; Zare, Firuz [School of Engineering, Queensland University of Technology, 2 George Street, Brisbane, Queensland 4001 (Australia)

    2010-08-15

    This paper shows how the power quality can be improved in a microgrid that is supplying a nonlinear and unbalanced load. The microgrid contains a hybrid combination of inertial and converter interfaced distributed generation units where a decentralized power sharing algorithm is used to control its power management. One of the distributed generators in the microgrid is used as a power quality compensator for the unbalanced and harmonic load. The current reference generation for power quality improvement takes into account the active and reactive power to be supplied by the micro-source which is connected to the compensator. Depending on the power requirement of the nonlinear load, the proposed control scheme can change modes of operation without any external communication interfaces. The compensator can operate in two modes depending on the entire power demand of the unbalanced nonlinear load. The proposed control scheme can even compensate system unbalance caused by the single-phase micro-sources and load changes. The efficacy of the proposed power quality improvement control and method in such a microgrid is validated through extensive simulation studies using PSCAD/EMTDC software with detailed dynamic models of the micro-sources and power electronic converters. (author)

  16. Recombinant 4 syndrome due to an unbalanced pericentric inversion of chromosome 4.

    Science.gov (United States)

    Battaglia, A; Brothman, A R; Carey, J C

    2002-09-15

    An informative patient with a MCA/MR syndrome consisting of developmental delay, prenatal onset growth delay, microcephaly, distinctive face, iris coloboma, and a congenital heart defect was found, on chromosome analysis, to have the following complement: 46,XY,rec(4) dup(4p) inv(4)(p14q35.1) mat. He has a partial 4p trisomy/distal 4q deletion due to an unbalanced pericentric inversion inherited from his mother. Dup (4p) trisomy was originally described by Wilson et al. [1970: Am J Hum Genet 22:679-690] in a similar case with the same chromosome 4 inversion. To date, at least 85 cases of dup (4p) syndrome have been published, mostly due to unbalanced translocations. Recent articles suggest that the phenotype is hard to recognize clinically due to the lack of specificity of findings. In contrast, 4p trisomy due to an unbalanced pericentric inversion of chromosome 4(p14q35), i.e., the recombinant 4 syndrome observed in our patient, appears to be a discrete entity with relatively consistent features. In total there are four other kindreds described in the literature with this inversion, and the phenotype seems recognizable. Thus, we suggest that recombinant 4 syndrome is a discrete entity among 4p trisomy patients. Copyright 2002 Wiley-Liss, Inc.

  17. A study on the force balance of an unbalanced globe valve

    International Nuclear Information System (INIS)

    Yang, Sang Min; Cho, Taik Dong; Ko, Sung Ho; Lee, Ho Young

    2007-01-01

    A pneumatic control valve is a piping element that controls the volumetric flow rate and pressure of a fluid: it is necessary to analyze the characteristics of the forces with respect to the opening of the valve in order to evaluate its operating performance. The forces occurring during operation are: resisting force and actuator force, where the load resistance is mostly affected by the fluid pressure difference of the valve. In this study, a force balance equation derived from the equilibrium relationship between the resisting force and the actuator force of an unbalanced globe valve is proposed, and the force balance equations are used to model the dynamic equations of a pneumatic unbalanced globe valve installed in nuclear power plants. A CFD analysis is also carried out to evaluate the pressure distribution and forces acting on the top and bottom planes of the valve plug. The results of this analysis have been verified through experimentation. This study has shown that the fluid pressure difference between the inlet and outlet of the valve, measured from the force balance equation of an unbalanced valve, should actually be examined with the fluid-pressure difference between the top and bottom side of the valve plug

  18. A control strategy for grid-side converter of DFIG under unbalanced condition based on Dig SILENT/Power Factory

    Science.gov (United States)

    Han, Pingping; Zhang, Haitian; Chen, Lingqi; Zhang, Xiaoan

    2018-01-01

    The models of doubly fed induction generator (DFIG) and its grid-side converter (GSC) are established under unbalanced grid condition based on DIgSILENT/PowerFactory. According to the mathematical model, the vector equations of positive and negative sequence voltage and current are deduced in the positive sequence synchronous rotating reference frame d-q-0 when the characteristics of the simulation software are considered adequately. Moreover, the reference value of current component of GSC in the positive sequence frame d-q-0 under unbalanced condition can be obtained to improve the traditional control of GSC when the national issue of unbalanced current limits is combined. The simulated results indicate that the control strategy can restrain negative sequence current and the two times frequency power wave of GSC’s ac side effectively. The voltage of DC bus can be maintained a constant to ensure the uninterrupted operation of DFIG under unbalanced grid condition eventually.

  19. DC-Voltage Fluctuation Elimination Through a DC-Capacitor Current Control for DFIG Converters Under Unbalanced Grid Voltage Conditions

    DEFF Research Database (Denmark)

    Liu, Changjin; Xu, Dehong; Zhu, Nan

    2013-01-01

    Unbalanced grid voltage causes a large second-order harmonic current in the dc-link capacitors as well as dc-voltage fluctuation, which potentially will degrade the lifespan and reliability of the capacitors in voltage source converters. This paper proposes a novel dc-capacitor current control...... method for a grid-side converter (GSC) to eliminate the negative impact of unbalanced grid voltage on the dc-capacitors. In this method, a dc-capacitor current control loop, where a negative-sequence resonant controller is used to increase the loop gain, is added to the conventional GSC current control...... loop. The rejection capability to the unbalanced grid voltage and the stability of the proposed control system are discussed. The second-order harmonic current in the dc capacitor as well as dc-voltage fluctuation is very well eliminated. Hence, the dc capacitors will be more reliable under unbalanced...

  20. Liquid sodium pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

    1979-03-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  1. Income pooling within families

    DEFF Research Database (Denmark)

    Bonke, Jens; Uldall-Poulsen, Hans

    This paper analyses the phenomenon of income-pooling by applying the Danish household expenditure survey, merged with authoritative register information. Responses to additional questions on income sharing among 1696 couples also allows us to analyses whether the intra-household distribution...

  2. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  3. Serially-Connected Compensator for Eliminating the Unbalanced Three-Phase Voltage Impact on Wind Turbine Generators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z.; Hsu, P.; Muljadi, E.; Gao, W.

    2015-04-06

    Untransposed transmission lines, unbalanced tap changer operations, and unbalanced loading in weak distribution lines can cause unbalanced-voltage conditions. The resulting unbalanced voltage at the point of interconnection affects proper gird integration and reduces the lifetime of wind turbines due to power oscillations, torque pulsations, mechanical stresses, energy losses, and uneven and overheating of the generator stator winding. This work investigates the dynamic impact of unbalanced voltage on the mechanical and electrical components of integrated Fatigue, Aerodynamics, Structures, and Turbulence (FAST) wind turbine generation systems (WTGs) of Type 1 (squirrel-cage induction generator) and Type 3 (doubly-fed induction generator). To alleviate this impact, a serially-connected compensator for a three-phase power line is proposed to balance the wind turbine-side voltage. Dynamic simulation studies are conducted in MATLAB/Simulink to compare the responses of these two types of wind turbine models under normal and unbalanced-voltage operation conditions and demonstrate the effectiveness of the proposed compensator.

  4. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  5. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Roebert, G.A.

    1978-01-01

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  6. Fuel assembly storage pool

    International Nuclear Information System (INIS)

    Hiranuma, Hiroshi.

    1976-01-01

    Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

  7. CERN Electronics Pool presentations

    CERN Multimedia

    2011-01-01

    The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

  8. Swimming Pools and Molluscum Contagiosum

    Science.gov (United States)

    ... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

  9. Power Quality Assessment in Real Shipboard Microgrid Systems under Unbalanced and Harmonic AC Bus Voltage

    DEFF Research Database (Denmark)

    Liu, Wenzhao; Tarasiuk, Tomasz; Gorniak, Mariusz

    2018-01-01

    were proposed and carried out in a real ship under sea-going conditions to address this problem. The ship experimental results were presented and discussed considering non-linear bow thruster load and high power ballast pump loads under unbalanced and harmonic voltage conditions. In addition......, the analysis of voltage transient dips during ballast pump starting up is presented. Further, the voltage/current distortions of working generator, bow thruster and pump loads are analyzed. The paper provides a valuable analysis for coping with PQ issues in the real ship power system....

  10. Performance of unbalanced QPSK in the presence of noisy reference and crosstalk

    Science.gov (United States)

    Divsalar, D.; Yuen, J. H.

    1979-01-01

    The problem of transmitting two telemetry data streams having different rates and different powers using unbalanced quadriphase shift keying (UQPSK) signaling is considered. It is noted that the presence of a noisy carrier phase reference causes a degradation in detection performance in coherent communications systems and that imperfect carrier synchronization not only attenuates the main demodulated signal voltage in UQPSK but also produces interchannel interference (crosstalk) which degrades the performance still further. Exact analytical expressions for symbol error probability of UQPSK in the presence of noise phase reference are derived.

  11. Grid Voltage Modulated Control of Grid-Connected Voltage Source Inverters under Unbalanced Grid Conditions

    DEFF Research Database (Denmark)

    Li, Mingshen; Gui, Yonghao; Quintero, Juan Carlos Vasquez

    2017-01-01

    In this paper, an improved grid voltage modulated control (GVM) with power compensation is proposed for grid-connected voltage inverters when the grid voltage is unbalanced. The objective of the proposed control is to remove the power ripple and to improve current quality. Three power compensation...... objectives are selected to eliminate the negative sequence components of currents. The modified GVM method is designed to obtain two separate second-order systems for not only the fast convergence rate of the instantaneous active and reactive powers but also the robust performance. In addition, this method...

  12. Distributed Strategy for Optimal Dispatch of Unbalanced Three-Phase Islanded Microgrids

    DEFF Research Database (Denmark)

    Vergara Barrios, Pedro Pablo; Rey-López, Juan Manuel; Shaker, Hamid Reza

    2018-01-01

    This paper presents a distributed strategy for the optimal dispatch of islanded microgrids, modeled as unbalanced three-phase electrical distribution systems (EDS). To set the dispatch of the distributed generation (DG) units, an optimal generation problem is stated and solved distributively based......-phase microgrid. According to the obtained results, the proposed strategy achieves a lower cost solution when compared with a centralized approach based on a static droop framework, with a considerable reduction on the communication system complexity. Additionally, it corrects the mismatch between generation...

  13. DC-link voltage oscillations reduction during unbalanced grid faults for high power wind turbines

    DEFF Research Database (Denmark)

    Delpino, Hernan Anres Miranda; Teodorescu, Remus; Rodriguez, Pedro

    2011-01-01

    During unbalanced grid voltage faults the Power injected to the grid experiences 100Hz oscillations as a result of interactions between positive and negative sequence components of three-phase voltages and currents. These oscillations can become as high as %50 percent of the rated power....... In this article an improved controller is proposed which present different behavior during normal operation and faults to keep track of non-sinusoidal current reference signals. The reference signals are calculated to obtain zero power oscillations. Reconfigurable resonant controllers are used for this purpose...

  14. Frequency Noise Suppression of a Single Mode Laser with an Unbalanced Fiber Interferometer for Subnanometer Interferometry

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Radek; Čížek, Martin; Mikel, Břetislav; Číp, Ondřej

    2015-01-01

    Roč. 15, č. 1 (2015), s. 1342-1355 ISSN 1424-8220 R&D Projects: GA ČR(CZ) GPP102/12/P962; GA ČR GAP102/10/1813; GA TA ČR TA01010995; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : unbalanced interferometer * fiber spool * PI control * frequency noise Subject RIV: BH - Optics , Masers, Lasers Impact factor: 2.033, year: 2015

  15. Experimental verification and analytical calculation of unbalanced magnetic force in permanent magnet machines

    Directory of Open Access Journals (Sweden)

    Kyung-Hun Shin

    2017-05-01

    Full Text Available In this study, an exact analytical solution based on Fourier analysis is proposed to compute the unbalanced magnetic force in a permanent magnet machine. The magnetic field solutions are obtained by using a magnetic vector potential and by selecting the appropriate boundary conditions. Based on these field solutions, the force characteristics are also determined analytically. All analytical results were extensively validated with nonlinear two-dimensional finite element analysis and experimental results. Using proposed method, we investigated the influence on the UMF according to machine parameters. Therefore, the proposed method should be very useful in initial design and optimization process of PM machines for UMF analysis.

  16. Secondary wavelength stabilization of unbalanced Michelson interferometers for the generation of low-jitter pulse trains.

    Science.gov (United States)

    Shalloo, R J; Corner, L

    2016-09-01

    We present a double unbalanced Michelson interferometer producing up to four output pulses from a single input pulse. The interferometer is stabilized with the Hänsch-Couillaud method using an auxiliary low power continuous wave laser injected into the interferometer, allowing the stabilization of the temporal jitter of the output pulses to 0.02 fs. Such stabilized pulse trains would be suitable for driving multi-pulse laser wakefield accelerators, and the technique could be extended to include amplification in the arms of the interferometer.

  17. Investigation of Grid-connected Voltage Source Converter Performance under Unbalanced Faults

    DEFF Research Database (Denmark)

    Jia, Jundi; Yang, Guangya; Nielsen, Arne Hejde

    2016-01-01

    Renewable energy sources (RES) and HVDC links are typically interfaced with the grid by power converters, whose performance during grid faults is significantly different from that of traditional synchronous generators. This paper investigates the performance of grid-connected voltage source...... that the performance of VSCs varies with their control strategies. Negative-sequence current control is necessary to restrict converter current in each phase under unbalanced faults. Among presented control strategies, the balanced current control strategy complies with the present voltage support requirement best...

  18. Data Normalization of (1)H NMR Metabolite Fingerprinting Data Sets in the Presence of Unbalanced Metabolite Regulation.

    Science.gov (United States)

    Hochrein, Jochen; Zacharias, Helena U; Taruttis, Franziska; Samol, Claudia; Engelmann, Julia C; Spang, Rainer; Oefner, Peter J; Gronwald, Wolfram

    2015-08-07

    Data normalization is an essential step in NMR-based metabolomics. Conducted properly, it improves data quality and removes unwanted biases. The choice of the appropriate normalization method is critical and depends on the inherent properties of the data set in question. In particular, the presence of unbalanced metabolic regulation, where the different specimens and cohorts under investigation do not contain approximately equal shares of up- and down-regulated features, may strongly influence data normalization. Here, we demonstrate the suitability of the Shapiro-Wilk test to detect such unbalanced regulation. Next, employing a Latin-square design consisting of eight metabolites spiked into a urine specimen at eight different known concentrations, we show that commonly used normalization and scaling methods fail to retrieve true metabolite concentrations in the presence of increasing amounts of glucose added to simulate unbalanced regulation. However, by learning the normalization parameters on a subset of nonregulated features only, Linear Baseline Normalization, Probabilistic Quotient Normalization, and Variance Stabilization Normalization were found to account well for different dilutions of the samples without distorting the true spike-in levels even in the presence of marked unbalanced metabolic regulation. Finally, the methods described were applied successfully to a real world example of unbalanced regulation, namely, a set of plasma specimens collected from patients with and without acute kidney injury after cardiac surgery with cardiopulmonary bypass use.

  19. Pool-type reactor

    International Nuclear Information System (INIS)

    Hopkins, S.R.

    1977-01-01

    This invention relates to a pool nuclear reactor fitted with a perfected system to raise the buckets into a vertical position at the bottom of a channel. This reactor has an inclined channel to guide a bucket containing a fuel assembly to introduce it into the reactor jacket or extract it therefrom and a damper at the bottom of the channel to stop the drop of the bucket. An upright vertically movable rod has a horizontally articulated arm with a hook. This can pivot to touch a radial lug on the bucket and pivot the bucket around its base in a vertical position, when the rod moves up [fr

  20. Analysis of Nonlinear Vibration in Permanent Magnet Synchronous Motors under Unbalanced Magnetic Pull

    Directory of Open Access Journals (Sweden)

    Ao Zhang

    2018-01-01

    Full Text Available The vibration and noise of permanent magnet synchronous motors (PMSM are mainly caused by unbalanced magnetic pull (UMP. This paper aims to investigate nonlinear vibration in PMSMs. Firstly, the analytical model of the air-gap magnetic field with an eccentric rotor in PMSM is studied, and the analytical model is verified by the finite element method. Then the dynamic model of an offset rotor-bearing system is established, and the gyroscopic effect, nonlinear bearing force and UMP are taken into consideration. Finally, the dynamic characteristics of different static displacement eccentricities, rotor offsets and radial clearances are investigated in both the time domain and the frequency domain. The results show that the amplitudes of dynamic responses increase with the static displacement eccentricity and rotor offset and high integer multiples of rotating frequency appear with the increase of displacement eccentricity. The coupling effects of bearing force, unbalanced mass force and UMP are observed in the frequency domain, and the frequency components in the dynamic responses indicate that the bearings have an effect on the system.

  1. Fabrication and characterization of self-folding thermoplastic sheets using unbalanced thermal shrinkage.

    Science.gov (United States)

    Danielson, Christian; Mehrnezhad, Ali; YekrangSafakar, Ashkan; Park, Kidong

    2017-06-14

    Self-folding or micro-origami technologies are actively investigated as a novel manufacturing process to fabricate three-dimensional macro/micro-structures. In this paper, we present a simple process to produce a self-folding structure with a biaxially oriented polystyrene sheet (BOPS) or Shrinky Dinks. A BOPS sheet is known to shrink to one-third of its original size in plane, when it is heated above 160 °C. A grid pattern is engraved on one side of the BOPS film with a laser engraver to decrease the thermal shrinkage of the engraved side. The thermal shrinkage of the non-engraved side remains the same and this unbalanced thermal shrinkage causes folding of the structure as the structure shrinks at high temperature. We investigated the self-folding mechanism and characterized how the grid geometry, the grid size, and the power of the laser engraver affect the bending curvature. The developed fabrication process to locally modulate thermomechanical properties of the material by engraving the grid pattern and the demonstrated design methodology to harness the unbalanced thermal shrinkage can be applied to develop complicated self-folding macro/micro structures.

  2. Performance Evaluation of UPQC under Nonlinear Unbalanced Load Conditions Using Synchronous Reference Frame Based Control

    Science.gov (United States)

    Kota, Venkata Reddy; Vinnakoti, Sudheer

    2017-12-01

    Today, maintaining Power Quality (PQ) is very important in the growing competent world. With new equipments and devices, new challenges are also being put before power system operators. Unified Power Quality Conditioner (UPQC) is proposed to mitigate many power quality problems and to improve the performance of the power system. In this paper, an UPQC with Fuzzy Logic controller for capacitor voltage balancing is proposed in Synchronous Reference Frame (SRF) based control with Modified Phased Locked Loop (MPLL). The proposed controller with SRF-MPLL based control is tested under non-linear and unbalanced load conditions. The system is developed in Matlab/Simulink and its performance is analyzed under various conditions like non-linear, unbalanced load and polluted supply voltage including voltage sag/swells. Active and reactive power flow in the system, power factor and %THD of voltages and currents before and after compensation are also analyzed in this work. Results prove the applicability of the proposed scheme for power quality improvement. It is observed that the fuzzy controller gives better performance than PI controller with faster capacitor voltage balancing and also improves the dynamic performance of the system.

  3. A set of 14 DIP-SNP markers to detect unbalanced DNA mixtures.

    Science.gov (United States)

    Liu, Zhizhen; Liu, Jinding; Wang, Jiaqi; Chen, Deqing; Liu, Zidong; Shi, Jie; Li, Zeqin; Li, Wenyan; Zhang, Gengqian; Du, Bing

    2018-03-04

    Unbalanced DNA mixture is still a difficult problem for forensic practice. DIP-STRs are useful markers for detection of minor DNA but they are not widespread in the human genome and having long amplicons. In this study, we proposed a novel type of genetic marker, termed DIP-SNP. DIP-SNP refers to the combination of INDEL and SNP in less than 300bp length of human genome. The multiplex PCR and SNaPshot assay were established for 14 DIP-SNP markers in a Chinese Han population from Shanxi, China. This novel compound marker allows detection of the minor DNA contributor with sensitivity from 1:50 to 1:1000 in a DNA mixture of any gender with 1 ng-10 ng DNA template. Most of the DIP-SNP markers had a relatively high probability of informative alleles with an average I value of 0.33. In all, we proposed DIP-SNP as a novel kind of genetic marker for detection of minor contributor from unbalanced DNA mixture and established the detection method by associating the multiplex PCR and SNaPshot assay. DIP-SNP polymorphisms are promising markers for forensic or clinical mixture examination because they are shorter, widespread and higher sensitive. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Comparative study of niobium nitride coatings deposited by unbalanced and balanced magnetron sputtering

    International Nuclear Information System (INIS)

    Olaya, J.J.; Rodil, S.E.; Muhl, S.

    2008-01-01

    Niobium nitride (NbN) coatings have many interesting properties such as chemical inertness, excellent mechanical properties, high electrical conductivity, high melting point, and a superconducting transition temperature between 16 and 17 K. For this reason, these compounds have many potential thin film applications. In this work we compare the properties of NbN x films deposited using well-characterized balanced and unbalanced magnetron sputtering systems. Samples of NbN were deposited in the two systems under almost identical deposition conditions, that is, the same substrate temperature, plasma power, gas pressure, substrate to target distance and Ar/N 2 ratio. Prior to the film preparation both the magnetic field geometry and the characteristics of the plasma were determined. The microstructure and composition of the deposits were analyzed by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The corrosion resistance and the micro-abrasion wear resistance were measured by anodic polarization potentiodynamic studies and by ball cratering, respectively. The NbN films grown using the highly unbalanced magnetron configuration had a preferential (111) crystal orientation and a composite hardness of up to 2400 HV 0.025 . While the films deposited using the balanced magnetron had a mixed crystalline orientation and a hardness of 2000 HV 0.025 . The results demonstrate the strong effect of magnetic field configuration on the ion bombardment, and the resultant coating characteristics

  5. Comparative study of niobium nitride coatings deposited by unbalanced and balanced magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Olaya, J.J. [Departamento de Ingenieria Mecanica y Mecatronica, Universidad Nacional de Colombia, Bogota Colombia (Colombia); Rodil, S.E. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Mexico D. F. 04510 (Mexico); Muhl, S. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Mexico D. F. 04510 (Mexico)], E-mail: muhl@servidor.unam.mx

    2008-10-01

    Niobium nitride (NbN) coatings have many interesting properties such as chemical inertness, excellent mechanical properties, high electrical conductivity, high melting point, and a superconducting transition temperature between 16 and 17 K. For this reason, these compounds have many potential thin film applications. In this work we compare the properties of NbN{sub x} films deposited using well-characterized balanced and unbalanced magnetron sputtering systems. Samples of NbN were deposited in the two systems under almost identical deposition conditions, that is, the same substrate temperature, plasma power, gas pressure, substrate to target distance and Ar/N{sub 2} ratio. Prior to the film preparation both the magnetic field geometry and the characteristics of the plasma were determined. The microstructure and composition of the deposits were analyzed by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The corrosion resistance and the micro-abrasion wear resistance were measured by anodic polarization potentiodynamic studies and by ball cratering, respectively. The NbN films grown using the highly unbalanced magnetron configuration had a preferential (111) crystal orientation and a composite hardness of up to 2400 HV{sub 0.025}. While the films deposited using the balanced magnetron had a mixed crystalline orientation and a hardness of 2000 HV{sub 0.025}. The results demonstrate the strong effect of magnetic field configuration on the ion bombardment, and the resultant coating characteristics.

  6. Assessing harmonic current source modelling and power definitions in balanced and unbalanced networks

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson-Hope, Gary; Stemmet, W.C. [Cape Peninsula University of Technology, Cape Town Campus, Cape Town (South Africa)

    2006-07-01

    The purpose of this paper is to assess the DlgSILENT PowerFactory software power definitions (indices) in terms of phase and sequence components for balanced and unbalanced networks when harmonic distortion is present and to compare its results to hand calculations done, following recommendation made by the IEEE Working Group on this topic. This paper also includes the development of a flowchart for calculating power indices in balanced and unbalanced three-phase networks when non-sinusoidal voltages and currents are present. A further purpose is to determine how two industrial grade harmonic analysis software packages (DlgSILENT and ERACS) model three-phase harmonic sources used for current penetration studies and to compare their results when applied to a network. From the investigations, another objective was to develop a methodology for modelling harmonic current sources based on a spectrum obtained from measurements. Three case studies were conducted and the assessment and developed methodologies were shown to be effective. (Author)

  7. Double-Frame Current Control with a Multivariable PI Controller and Power Compensation for Weak Unbalanced Networks

    CERN Document Server

    Siemaszko, Daniel

    2015-06-15

    The handling of weak networks with asymmetric loads and disturbances im- plies the accurate handling of the second-harmonic component that appears in an unbalanced network. This paper proposes a classic vector control approach using a PI-based controller with superior decoupling capabilities for operation in weak networks with unbalanced phase voltages. A synchronization method for weak unbalanced networks is detailed, with dedicated dimensioning rules. The use of a double-frame controller allows a current symmetry or controlled imbalance to be forced for compensation of power oscillations by controlling the negative current sequence. This paper also serves as a useful reminder of the proper way to cancel the inherent coupling effect due to the transformation to the synchronous rotating reference frame, and of basic considerations of the relationship between switching frequency and control bandwidth.

  8. Control Strategy for Three-Phase Grid-Connected PV Inverters Enabling Current Limitation Under Unbalanced Faults

    DEFF Research Database (Denmark)

    Afshari, Ehsan; Moradi, Gholam Reza; Rahimi, Ramin

    2017-01-01

    Power quality and voltage control are among the most important aspects of the grid-connected power converter operation under faults. Non-sinusoidal current is injected during unbalanced voltage sag and active or/and reactive power includes double frequency content. This paper introduces a novel...... control strategy to mitigate the double grid frequency oscillations in the active power and dc-link voltage of the two-stage three-phase grid-connected Photovoltaic (PV) inverters during unbalanced faults. With the proposed control method, PV inverter injects sinusoidal currents under unbalanced grid...... faults. In addition, an efficient and easy-to-implement current limitation method is introduced, which can effectively limit the injected currents to the rated value during faults. In this case, the fault-ride-through operation is ensured and it will not trigger the overcurrent protection. A non...

  9. Analysis of Unbalanced Magnetic Pull in Wound Rotor Induction Machines using Finite Element Analysis – Transient, Motoring and Generating Modes

    DEFF Research Database (Denmark)

    Dorrell, David G.; Hermann, Alexander Niels August; Jensen, Bogi Bech

    2013-01-01

    eccentricity. The operating conditions are varied so that transient, motoring and doubly-fed induction generator modes are studied. This allows greater understanding of the radial forces involved. Wound rotor induction machines exhibit higher unbalanced magnetic pull than cage induction machines so......There has been much literature on unbalanced magnetic pull in various types of electrical machine. This can lead to bearing wear and additional vibrations in the machine. In this paper a wound rotor induction is studied. Finite element analysis studies are conducted when the rotor has 10 % rotor...

  10. Hysteresis Control for Shunt Active Power Filter under Unbalanced Three-Phase Load Conditions

    Directory of Open Access Journals (Sweden)

    Z. Chelli

    2015-01-01

    Full Text Available This paper focuses on a four-wire shunt active power filter (APF control scheme proposed to improve the performance of the APF. This filter is used to compensate harmonic distortion in three-phase four-wire systems. Several harmonic suppression techniques have been widely proposed and applied to minimize harmonic effects. The proposed control scheme can compensate harmonics and reactive power of the nonlinear loads simultaneously. This approach is compared to the conventional shunt APF reference compensation strategy. The developed algorithm is validated by simulation tests using MATLAB Simulink. The obtained results have demonstrated the effectiveness of the proposed scheme and confirmed the theoretical developments for balanced and unbalanced nonlinear loads.

  11. High-efficiency interaction-free measurement with an unbalanced Mach–Zehnder interferometer

    Science.gov (United States)

    Chao, Liu; Jinhong, Liu; Junxiang, Zhang; Shiyao, Zhu

    2018-06-01

    The presence of an object can be detected without the absorption of photons in an interaction-free measurement (IFM) system based on the Zeno effect in chained Mach–Zehnder interferometers (MZIs). In this paper, we propose a scheme with an unbalanced MZI to perform the transmission of two frequency components of input light simultaneously. The two components are separated at two output ports of the MZI, achieving a high probability of asserting the absence of the object. The two final outputs of the MZI can also be extended to perform special information processing via IFM. As a result, this proposal contributes to the improvement of efficiency in interaction-free measurements with a very small number of interferometers for potential practical implementations of quantum information technology.

  12. A cautionary note on generalized linear models for covariance of unbalanced longitudinal data

    KAUST Repository

    Huang, Jianhua Z.

    2012-03-01

    Missing data in longitudinal studies can create enormous challenges in data analysis when coupled with the positive-definiteness constraint on a covariance matrix. For complete balanced data, the Cholesky decomposition of a covariance matrix makes it possible to remove the positive-definiteness constraint and use a generalized linear model setup to jointly model the mean and covariance using covariates (Pourahmadi, 2000). However, this approach may not be directly applicable when the longitudinal data are unbalanced, as coherent regression models for the dependence across all times and subjects may not exist. Within the existing generalized linear model framework, we show how to overcome this and other challenges by embedding the covariance matrix of the observed data for each subject in a larger covariance matrix and employing the familiar EM algorithm to compute the maximum likelihood estimates of the parameters and their standard errors. We illustrate and assess the methodology using real data sets and simulations. © 2011 Elsevier B.V.

  13. Robust Multi-Objective PQ Scheduling for Electric Vehicles in Flexible Unbalanced Distribution Grids

    DEFF Research Database (Denmark)

    Knezovic, Katarina; Soroudi, Alireza; Marinelli, Mattia

    2017-01-01

    With increased penetration of distributed energy resources and electric vehicles (EVs), different EV management strategies can be used for mitigating adverse effects and supporting the distribution grid. This paper proposes a robust multi-objective methodology for determining the optimal day...... demand response programs. The method is tested on a real Danish unbalanced distribution grid with 35% EV penetration to demonstrate the effectiveness of the proposed approach. It is shown that the proposed formulation guarantees an optimal EV cost as long as the price uncertainties are lower than....... The robust formulation effectively considers the errors in the electricity price forecast and its influence on the EV schedule. Moreover, the impact of EV reactive power support on objective values and technical parameters is analysed both when EVs are the only flexible resources and when linked with other...

  14. Power quality improvement of unbalanced power system with distributed generation units

    DEFF Research Database (Denmark)

    Hu, Y.; Chen, Zhe; Excell, P.

    2011-01-01

    This paper presents a power electronic system for improving the power quality of the unbalanced distributed generation units in three-phase four-wire system. In the system, small renewable power generation units, such as small PV generator, small wind turbines may be configured as single phase...... and control of the converter are described. Simulation results have demonstrated that the system can effectively correct the unbalance and enhance the system power quality....... generation units. The random nature of renewable power sources may result in significant unbalance in the power network and affect the power quality. An electronic converter system is proposed to correct the system unbalance and harmonics so as to deal with the power quality problems. The operation...

  15. Analysis of Three-Phase Rectifier Systems with Controlled DC-Link Current Under Unbalanced Grids

    DEFF Research Database (Denmark)

    Kumar, Dinesh; Davari, Pooya; Zare, Firuz

    2017-01-01

    Voltage unbalance is the most common disturbance in distribution networks, which give undesirable effects on many grid connected power electronics systems including Adjustable Speed Drive (ASD). Severe voltage unbalance can force three-phase rectifiers into almost single-phase operation, which...... degrades the grid power quality and also imposes a significant negative impact on the ASD system. This major power quality issue affecting the conventional rectifiers can be attenuated by controlling the DC-link current based on an Electronic Inductor (EI) technique. The purpose of this digest...... is to analyze and compare the performance of an EI with a conventional three-phase rectifier under unbalanced grid conditions. Experimental and simulation results validate the proposed mathematical modelling. Further analysis and benchmarking will be provided in the final paper....

  16. Is there a yet unreported unbalanced chromosomal abnormality without phenotypic consequences in proximal 4p?

    Science.gov (United States)

    Liehr, T; Bartels, I; Zoll, B; Ewers, E; Mrasek, K; Kosyakova, N; Merkas, M; Hamid, A B; von Eggeling, F; Posorski, N; Weise, A

    2011-01-01

    Unbalanced chromosomal abnormalities (UBCA) are reported for >50 euchromatic regions of almost all human autosomes. UBCA are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. Here we report on a partial trisomy of chromosome 4 of the centromere-near region of the short arm of chromosome 4 present as a small supernumerary marker chromosome (sSMC). The sSMC was present in >70% of amnion cells and in 60% of placenta. Further delineation of the size of the duplicated region was done by molecular cytogenetics and array comparative genomic hybridization. Even though the sSMC lead to a partial trisomy of ~9 megabase pairs, a healthy child was born, developing normally at 1 year of age. No comparable cases are available in the literature. Thus, we discuss here the possibility of having found a yet unrecognized chromosomal region subject to UBCA. Copyright © 2010 S. Karger AG, Basel.

  17. Effects of balanced and unbalanced voltage sags on DC adjustable-speed drives

    Energy Technology Data Exchange (ETDEWEB)

    Pedra, Joaquin; Sainz, Luis; Corcoles, Felipe; Bergas, Joan [Department of Electrical Engineering, ETSEIB-UPC, Av. Diagonal, 647, 08028 Barcelona (Spain); de Blas, Alfredo [Department of Electrical Engineering, EUETIB-UPC, C. d' Urgell, 187, 08036 Barcelona (Spain)

    2008-06-15

    This paper analyzes the sensitivity of DC adjustable-speed drives to balanced and unbalanced voltage sags. The influence of sag type, depth, duration and phase-angle jump on DC drives is studied. The control of the DC drive has been taken into account to understand drive behavior in the presence of voltage sags. Two working modes of the DC motor are considered in the study: as a consumer load and as a regenerative load. When the DC motor works as a consumer load, the study shows that sag type and depth have a significant influence on drive behavior. However, the voltage sag can be ridden through if the rectifier firing angle is set correctly by the control. When the DC motor works as a regenerative load, the study shows the consequences of the three-phase rectifier commutation failure due to the voltage sag. (author)

  18. Investigation of Unbalanced Magnetic Force in Magnetic Geared Machine Using Analytical Methods

    DEFF Research Database (Denmark)

    Zhang, Xiaoxu; Liu, Xiao; Chen, Zhe

    2016-01-01

    The electromagnetic structure of the magnetic geared machine (MGM) may induce a significant unbalanced magnetic force (UMF). However, few methods have been developed to theoretically reveal the essential reasons for this issue in the MGM. In this paper, an analytical method based on an air....... Second, the magnetic field distribution in the MGM is modeled by an exact subdomain method, which allows the magnetic forces to be calculated quantitatively. The magnetic forces in two MGMs are then studied under no-load and full-load conditions. Finally, the finite-element calculation confirms......-gap relative permeance theory is first developed to qualitatively study the origins of the UMF in the MGM. By means of formula derivations, three kinds of magnetic field behaviors in the air gaps are found to be the potential sources of UMF. It is also proved that the UMF is possible to avoid by design choices...

  19. Characteristics of W Doped Nanocrystalline Carbon Films Prepared by Unbalanced Magnetron Sputtering.

    Science.gov (United States)

    Park, Yong Seob; Park, Chul Min; Kim, Nam-Hoon; Kim, Jae-Moon

    2016-05-01

    Nanocrystalline tungsten doped carbon (WC) films were prepared by unbalanced magnetron sputtering. Tungsten was used as the doping material in carbon thin films with the aim of application as a contact strip in an electric railway. The structural, physical, and electrical properties of the fabricated WC films with various DC bias voltages were investigated. The films had a uniform and smooth surface. Hardness and frication characteristics of the films were improved, and the resistivity and sheet resistance decreased with increasing negative DC bias voltage. These results are associated with the nanocrystalline WC phase and sp(2) clusters in carbon networks increased by ion bombardment enhanced with increasing DC bias voltage. Consequently, the increase of sp(2) clusters containing WC nanocrystalline in the carbon films is attributed to the improvement in the physical and electrical properties.

  20. The microstructure and properties of titanium dioxide films synthesized by unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Leng, Y.X.; Chen, J.Y.; Yang, P.; Sun, H.; Huang, N.

    2007-01-01

    In this work, titanium oxide films were deposited on Ti6Al4V and Si (1 0 0) by DC unbalanced magnetron sputtering method at different oxygen pressure. X-ray diffraction (XRD), microhardness tests, pin-on-disk wear experiments, surface contact angle tests and platelet adhesion investigation were conducted to evaluate the properties of the films. The corrosion behavior of titanium dioxide films was characterized by potentiodynamic polarization. The results showed that titanium oxide films deposited by unbalance magnetron sputtering were compact and could obviously enhance microhardness, wear resistance of titanium alloy substrate. Potentiodynamic polarization curves showed that Ti-6Al-4V deposited with titanium dioxide films had lower dissolution currents than that of the uncoated one. The results of in vitro hemocompatibility analyses indicated that the blood compatibility of the titanium dioxide films with bandgap 3.2 eV have better blood compatibility

  1. African crop yield reductions due to increasingly unbalanced Nitrogen and Phosphorus consumption

    Science.gov (United States)

    van der Velde, Marijn; Folberth, Christian; Balkovič, Juraj; Ciais, Philippe; Fritz, Steffen; Janssens, Ivan A.; Obersteiner, Michael; See, Linda; Skalský, Rastislav; Xiong, Wei; Peñuealas, Josep

    2014-05-01

    The impact of soil nutrient depletion on crop production has been known for decades, but robust assessments of the impact of increasingly unbalanced nitrogen (N) and phosphorus (P) application rates on crop production are lacking. Here, we use crop response functions based on 741 FAO maize crop trials and EPIC crop modeling across Africa to examine maize yield deficits resulting from unbalanced N:P applications under low, medium, and high input scenarios, for past (1975), current, and future N:P mass ratios of respectively, 1:0.29, 1:0.15, and 1:0.05. At low N inputs (10 kg/ha), current yield deficits amount to 10% but will increase up to 27% under the assumed future N:P ratio, while at medium N inputs (50 kg N/ha), future yield losses could amount to over 40%. The EPIC crop model was then used to simulate maize yields across Africa. The model results showed relative median future yield reductions at low N inputs of 40%, and 50% at medium and high inputs, albeit with large spatial variability. Dominant low-quality soils such as Ferralsols, which are strongly adsorbing P, and Arenosols with a low nutrient retention capacity, are associated with a strong yield decline, although Arenosols show very variable crop yield losses at low inputs. Optimal N:P ratios, i.e. those where the lowest amount of applied P produces the highest yield (given N input) where calculated with EPIC to be as low as 1:0.5. Finally, we estimated the additional P required given current N inputs, and given N inputs that would allow Africa to close yield gaps (ca. 70%). At current N inputs, P consumption would have to increase 2.3-fold to be optimal, and to increase 11.7-fold to close yield gaps. The P demand to overcome these yield deficits would provide a significant additional pressure on current global extraction of P resources.

  2. A Review on Grid-connected Converter Control for Short Circuit Power Provision under Grid Unbalanced Faults

    DEFF Research Database (Denmark)

    Jia, Jundi; Yang, Guangya; Nielsen, Arne Hejde

    2017-01-01

    behave significantly different from the traditional alternators under grid faults. In order to evaluate the potential impact of future converter-based power systems on protective relays, it is necessary to consider diverse current control strategies of voltage source converters (VSC) under unbalanced...

  3. Performance analysis of active damped small DC-link capacitor based drive for unbalanced input voltage supply

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Munk-Nielsen, Stig

    2011-01-01

    A small DC-link capacitor based drive is presented in this paper. The drive shows negative impedance instability at operating points with high power load. A phase portrait is presented for input filter states which exhibit a limit cycle. When the drive is operated with unbalanced input supply...

  4. Performance Improvement of DFIG Wind Turbine Using Series Grid-Side Converter under Unbalanced Grid Voltage and Voltage Sag Conditions

    DEFF Research Database (Denmark)

    Shokri, Yunes; Ebrahimzadeh, Esmaeil; Lesani, Hamid

    2014-01-01

    under unbalanced grid voltage and small voltage sag conditions without needing additional DC link capacitor or energy storage unlike other methods. The control system includes negative and positive sequence controllers which make the stator voltage balanced and keep it constant at the nominal value...

  5. Analysis of temperature changes on three-phase synchronous generator using infrared: comparison between balanced and unbalanced load

    Science.gov (United States)

    Amien, S.; Yoga, W.; Fahmi, F.

    2018-02-01

    Synchronous generators are a major tool in an electrical energy generating systems, the load supplied by the generator is unbalanced. This paper discusses the effect of synchronous generator temperature on the condition of balanced load and unbalanced load, which will then be compared with the measurement result of both states of the generator. Unbalanced loads can be caused by various asymmetric disturbances in the power system and the failure of load forecasting studies so that the load distribution in each phase is not the same and causing the excessive heat of the generator. The method used in data collection was by using an infrared thermometer and resistance calculation method. The temperature comparison result between the resistive, inductive and capacitive loads in the highest temperature balance occured when the generator is loaded with a resistive load, where T = 31.9 ° C and t = 65 minutes. While in a state of unbalanced load the highest temperature occured when the generator is loaded with a capacitive load, where T = 40.1 ° C and t = 60 minutes. By understanding this behavior, we can maintain the generator for longer operation life.

  6. Assumption or Fact? Line-to-Neutral Voltage Expression in an Unbalanced 3-Phase Circuit during Inverter Switching

    Science.gov (United States)

    Masrur, M. A.

    2009-01-01

    This paper discusses the situation in a 3-phase motor or any other 3-phase system operating under unbalanced operating conditions caused by an open fault in an inverter switch. A dc voltage source is assumed as the input to the inverter, and under faulty conditions of the inverter switch, the actual voltage applied between the line to neutral…

  7. Balanced Current Control Strategy for Current Source Rectifier Stage of Indirect Matrix Converter under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Yeongsu Bak

    2016-12-01

    Full Text Available This paper proposes a balanced current control strategy for the current source rectifier (CSR stage of an indirect matrix converter (IMC under unbalanced grid voltage conditions. If the three-phase grid connected to the voltage source inverter (VSI of the IMC has unbalanced voltage conditions, it affects the currents of the CSR stage and VSI stage, and the currents are distorted. Above all, the distorted currents of the CSR stage cause instability in the overall system, which can affect the life span of the system. Therefore, in this paper, a control strategy for balanced currents in the CSR stage is proposed. To achieve balanced currents in the CSR stage, the VSI stage should receive DC power without ripple components from the CSR stage. This is implemented by controlling the currents in the VSI stage. Therefore, the proposed control strategy decouples the positive and negative phase-sequence components existing in the unbalanced voltages and currents of the VSI stage. Using the proposed control strategy under unbalanced grid voltage conditions, the stability and life span of the overall system can be improved. The effectiveness of the proposed control strategy is verified by simulation and experimental results.

  8. Echocardiographic definition and surgical decision-making in unbalanced atrioventricular septal defect: a Congenital Heart Surgeons' Society multiinstitutional study.

    Science.gov (United States)

    Jegatheeswaran, Anusha; Pizarro, Christian; Caldarone, Christopher A; Cohen, Meryl S; Baffa, Jeanne M; Gremmels, David B; Mertens, Luc; Morell, Victor O; Williams, William G; Blackstone, Eugene H; McCrindle, Brian W; Overman, David M

    2010-09-14

    Although identification of unbalanced atrioventricular septal defect (AVSD) is obvious when extreme, exact criteria to define the limits of unbalanced are not available. We sought to validate an atrioventricular valve index (AVVI) (left atrioventricular valve area/total atrioventricular valve area, centimeters squared) as a discriminator of balanced and unbalanced forms of complete AVSD and to characterize the association of AVVI with surgical strategies and outcomes. Diagnostic echocardiograms and hospital records of 356 infants with complete AVSD at 4 Congenital Heart Surgeons' Society (CHSS) institutions (2000-2006) were reviewed and AVVI measured (n=315). Patients were classified as unbalanced if AVVI≤0.4 (right dominant) or ≥0.6 (left dominant). Surgical strategy and outcomes were examined across the range of AVVI. Competing risks analysis until the time of commitment to a surgical strategy examined 4 end states: biventricular repair (BVR), univentricular repair (UVR), pulmonary artery banding (PAB), and death before surgery. A prediction nomogram for surgical strategy based on AVVI was developed. The majority of patients had balanced AVSD (0.4unbalanced AVSD with important correlation to anatomic substrate and selected surgical strategy.

  9. Model of large pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

    2006-08-21

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

  10. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  11. Design of hydrotherapy exercise pools.

    Science.gov (United States)

    Edlich, R F; Abidin, M R; Becker, D G; Pavlovich, L J; Dang, M T

    1988-01-01

    Several hydrotherapy pools have been designed specifically for a variety of aquatic exercise. Aqua-Ark positions the exerciser in the center of the pool for deep-water exercise. Aqua-Trex is a shallow underwater treadmill system for water walking or jogging. Swim-Ex generates an adjustable laminar flow that permits swimming without turning. Musculoskeletal conditioning can be accomplished in the above-ground Arjo shallow-water exercise pool. A hydrotherapy pool also can be custom designed for musculoskeletal conditioning in its shallow part and cardiovascular conditioning in a deeper portion of the pool. Regardless of the type of exercise, there is general agreement that the specific exercise conducted in water requires significantly more energy expenditure than when the same exercise is performed on land.

  12. Deoxypyrimidine monophosphate bypass therapy for thymidine kinase 2 deficiency

    OpenAIRE

    Garone, Caterina; Garc??a-D??az, Beatriz; Emmanuele, Valentina; L??pez Garc??a, Luis Carlos; Tadesse, Saba; Akman, Hasan O.; Tanji, Kurenai; Quinzii, Catarina M.; Hirano, Michio

    2014-01-01

    Autosomal recessive mutations in the thymidine kinase 2 gene (TK2) cause mitochondrial DNA depletion, multiple deletions, or both due to loss of TK2 enzyme activity and ensuing unbalanced deoxynucleotide triphosphate (dNTP) pools. To bypass Tk2 deficiency, we administered deoxycytidine and deoxythymidine monophosphates (dCMP+dTMP) to the Tk2 H126N (Tk2 −/− ) knock-in mouse model from postnatal day 4, when mutant mice are phenotypically normal, but biochemically affected. Assessment of 13-day-...

  13. ENERGY STAR Certified Pool Pumps

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.1 ENERGY STAR Program Requirements for Pool Pumps that are effective as of February 15,...

  14. Pooling and correlated neural activity

    Directory of Open Access Journals (Sweden)

    Robert Rosenbaum

    2010-04-01

    Full Text Available Correlations between spike trains can strongly modulate neuronal activity and affect the ability of neurons to encode information. Neurons integrate inputs from thousands of afferents. Similarly, a number of experimental techniques are designed to record pooled cell activity. We review and generalize a number of previous results that show how correlations between cells in a population can be amplified and distorted in signals that reflect their collective activity. The structure of the underlying neuronal response can significantly impact correlations between such pooled signals. Therefore care needs to be taken when interpreting pooled recordings, or modeling networks of cells that receive inputs from large presynaptic populations. We also show that the frequently observed runaway synchrony in feedforward chains is primarily due to the pooling of correlated inputs.

  15. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  16. Sustainability of common pool resources

    OpenAIRE

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepales...

  17. Sociological aspects of medicine and population unbalanced relationships in contemporary Russia

    Directory of Open Access Journals (Sweden)

    T V Semina

    2015-12-01

    Full Text Available The article considers sociological aspects of one of the most complex and urgent problems of the contemporary Russian society - the growing imbalance of social relationships between patients and doctors. Undoubtedly, in medicine each group - doctors and patients - is an element of poorly structured social network and an integral part of all types of interaction in the prevention and treatment of various diseases. This system of relationships is institutionalized and complex in itself, but social and economic processes can complicate or facilitate its functioning. Unfortunately, the growth of social differentiation in the Russian society in the last decades had a negative impact on all spheres of life including healthcare. Under given conditions and social stratification trends each group - doctors and patients - has developed specific value orientations as a kind of professional and personal quintessence of the current fundamental values. In particular, dissatisfaction with the financial situation in the light of work efforts and high level of education explains why doctors consider their social status inadequate and are forced to satisfy their material needs with the help of illegal means. The author proposes some measures to reduce the imbalance of medicine and society relationships in the contemporary Russian society, which suggest changing traditional models of healthcare and conflict management through the purposeful influence on the subject and object of the unbalanced relationships.

  18. A robust procedure for comparing multiple means under heteroscedasticity in unbalanced designs.

    Directory of Open Access Journals (Sweden)

    Esther Herberich

    2010-03-01

    Full Text Available Investigating differences between means of more than two groups or experimental conditions is a routine research question addressed in biology. In order to assess differences statistically, multiple comparison procedures are applied. The most prominent procedures of this type, the Dunnett and Tukey-Kramer test, control the probability of reporting at least one false positive result when the data are normally distributed and when the sample sizes and variances do not differ between groups. All three assumptions are non-realistic in biological research and any violation leads to an increased number of reported false positive results. Based on a general statistical framework for simultaneous inference and robust covariance estimators we propose a new statistical multiple comparison procedure for assessing multiple means. In contrast to the Dunnett or Tukey-Kramer tests, no assumptions regarding the distribution, sample sizes or variance homogeneity are necessary. The performance of the new procedure is assessed by means of its familywise error rate and power under different distributions. The practical merits are demonstrated by a reanalysis of fatty acid phenotypes of the bacterium Bacillus simplex from the "Evolution Canyons" I and II in Israel. The simulation results show that even under severely varying variances, the procedure controls the number of false positive findings very well. Thus, the here presented procedure works well under biologically realistic scenarios of unbalanced group sizes, non-normality and heteroscedasticity.

  19. Asymmetric Distributions of Energetic Circulating Ions and Sawtooth Control using ICCD and Unbalanced NBI

    International Nuclear Information System (INIS)

    Graves, J. P.

    2007-01-01

    There is little doubt that various auxiliary heating systems are successfully and routinely controlling sawteeth. There is however some room for improving our understanding of the mechanisms that influence these important changes to the discharges. A mechanism that appears to be common across ECCS, ICCD and unbalanced NBI discharges involves the effect of the q = 1 localised current drive perturbation on resistive diffusion during the sawtooth ramp. Nevertheless, it is important to look for explanations for sawtooth control which may exist in ion based auxiliary systems, but may differ or not exist in electron auxiliary means of sawtooth control. The reason for this is that monster sawteeth, initially lengthened by trapped energetic ions, have up to the present day only been controlled using ICCD, while in ITER the primary method for sawtooth control could be ECCD. A mechanism based on the finite orbit width of parallel asymmetric energetic circulating particles is only non-negligible for ion based auxiliary systems. The present contribution examines the relevance of the latter in sawtooth control experiments, such as those using ICCD and NBI at JET, by looking carefully at the role of circulating ions close to the trapped boundary. At such pitch angles the orbit width is largest, and the parallel asymmetry of the distribution function has the greatest influence. (Author)

  20. Voltage Impact of a Wave Energy Converter on an Unbalanced Distribution Grid and Corrective Actions

    Directory of Open Access Journals (Sweden)

    Hugo Mendonça

    2017-10-01

    Full Text Available Renewable energy is steadily increasing its penetration level in electric power systems. Wind and solar energy have reached a high degree of maturity, and their impacts on the grid are well known. However, this is not the case for emerging sources like wave energy. This work explores the impact of the fluctuating power injected by a wave energy converter on the distribution grid voltage and proposes a strategy for mitigating the induced voltage fluctuations. The paper describes the mechanics of how a fluctuating active power injection leads to grid voltage fluctuations and presents an unbalanced three-phase power flow tool that allows one to quantitatively analyze the voltage evolution at every phase and bus of a distribution grid driven by this power injection. The paper also proposes a corrective action for mitigating the voltage fluctuations that makes use of the hardware resources already available in the wave energy converter, by means of a control strategy on the reactive capability of the grid-side inverter. The use of a STATCOM as additional reactive compensation equipment is also explored. The effectiveness of the proposal is assessed in the IEEE 13-bus test feeder showing that, in some cases, the wave energy converter by itself is able to mitigate the voltage fluctuations that it causes. If not, a STATCOM can provide the extra reactive capability needed.

  1. Surface treatment effect on Si (111) substrate for carbon deposition using DC unbalanced magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Aji, A. S., E-mail: aji.ravazes70@gmail.com; Sahdan, M. F.; Hendra, I. B.; Dinari, P.; Darma, Y. [Quantum Semiconductor and Devices Lab., Physics of Material Electronics Research Division, Department of Physics, Institut Teknologi Bandung (Indonesia)

    2015-04-16

    In this work, we studied the effect of HF treatment in silicon (111) substrate surface for depositing thin layer carbon. We performed the deposition of carbon by using DC Unbalanced Magnetron Sputtering with carbon pallet (5% Fe) as target. From SEM characterization results it can be concluded that the carbon layer on HF treated substrate is more uniform than on substrate without treated. Carbon deposition rate is higher as confirmed by AFM results if the silicon substrate is treated by HF solution. EDAX characterization results tell that silicon (111) substrate with HF treatment have more carbon fraction than substrate without treatment. These results confirmed that HF treatment on silicon Si (111) substrates could enhance the carbon deposition by using DC sputtering. Afterward, the carbon atomic arrangement on silicon (111) surface is studied by performing thermal annealing process to 900 °C. From Raman spectroscopy results, thin film carbon is not changing until 600 °C thermal budged. But, when temperature increase to 900 °C, thin film carbon is starting to diffuse to silicon (111) substrates.

  2. Why Does Rebalancing Class-Unbalanced Data Improve AUC for Linear Discriminant Analysis?

    Science.gov (United States)

    Xue, Jing-Hao; Hall, Peter

    2015-05-01

    Many established classifiers fail to identify the minority class when it is much smaller than the majority class. To tackle this problem, researchers often first rebalance the class sizes in the training dataset, through oversampling the minority class or undersampling the majority class, and then use the rebalanced data to train the classifiers. This leads to interesting empirical patterns. In particular, using the rebalanced training data can often improve the area under the receiver operating characteristic curve (AUC) for the original, unbalanced test data. The AUC is a widely-used quantitative measure of classification performance, but the property that it increases with rebalancing has, as yet, no theoretical explanation. In this note, using Gaussian-based linear discriminant analysis (LDA) as the classifier, we demonstrate that, at least for LDA, there is an intrinsic, positive relationship between the rebalancing of class sizes and the improvement of AUC. We show that the largest improvement of AUC is achieved, asymptotically, when the two classes are fully rebalanced to be of equal sizes.

  3. Control of Active Front-End Rectifier in Electric Drive under Unbalanced Voltage Supply in Transient States

    Czech Academy of Sciences Publication Activity Database

    Chomát, Miroslav; Schreier, Luděk; Bendl, Jiří

    2012-01-01

    Roč. 88, 1A (2012), s. 177-180 ISSN 0033-2097 R&D Projects: GA ČR GA102/09/1273 Institutional research plan: CEZ:AV0Z20570509 Keywords : unbalanced voltage supply * DC-link voltage pulsations * pulse-width modulation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.244, year: 2011 http://www.red.pe.org.pl/abstract_pl.php?nid=5479

  4. Role of Wind Filtering and Unbalanced Flow Generation in Middle Atmosphere Gravity Wave Activity at Chatanika Alaska

    Directory of Open Access Journals (Sweden)

    Colin C. Triplett

    2017-01-01

    Full Text Available The meteorological control of gravity wave activity through filtering by winds and generation by spontaneous adjustment of unbalanced flows is investigated. This investigation is based on a new analysis of Rayleigh LiDAR measurements of gravity wave activity in the upper stratosphere-lower mesosphere (USLM,40–50kmon 152 nights at Poker Flat Research Range (PFRR, Chatanika, Alaska (65◦ N, 147◦ W, over 13 years between 1998 and 2014. The LiDAR measurements resolve inertia-gravity waves with observed periods between 1 h and 4 h and vertical wavelengths between 2 km and 10 km. The meteorological conditions are defined by reanalysis data from the Modern-Era Retrospective Analysis for Research and Applications (MERRA. The gravity wave activity shows large night-to-night variability, but a clear annual cycle with a maximum in winter,and systematic interannual variability associated with stratospheric sudden warming events. The USLM gravity wave activity is correlated with the MERRA winds and is controlled by the winds in the lower stratosphere through filtering by critical layer filtering. The USLM gravity wave activity is also correlated with MERRA unbalanced flow as characterized by the residual of the nonlinear balance equation. This correlation with unbalanced flow only appears when the wind conditions are taken into account, indicating that wind filtering is the primary control of the gravity wave activity.

  5. Seismic analysis of large pools

    Energy Technology Data Exchange (ETDEWEB)

    Dong, R.G.; Tokarz, F.J.

    1976-11-17

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

  6. Seismic analysis of large pools

    International Nuclear Information System (INIS)

    Dong, R.G.; Tokarz, F.J.

    1976-01-01

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

  7. Learning from unbalanced data: a cascade-based approach for detecting clustered microcalcifications.

    Science.gov (United States)

    Bria, A; Karssemeijer, N; Tortorella, F

    2014-02-01

    Finding abnormalities in diagnostic images is a difficult task even for expert radiologists because the normal tissue locations largely outnumber those with suspicious signs which may thus be missed or incorrectly interpreted. For the same reason the design of a Computer-Aided Detection (CADe) system is very complex because the large predominance of normal samples in the training data may hamper the ability of the classifier to recognize the abnormalities on the images. In this paper we present a novel approach for computer-aided detection which faces the class imbalance with a cascade of boosting classifiers where each node is trained by a learning algorithm based on ranking instead of classification error. Such approach is used to design a system (CasCADe) for the automated detection of clustered microcalcifications (μCs), which is a severely unbalanced classification problem because of the vast majority of image locations where no μC is present. The proposed approach was evaluated with a dataset of 1599 full-field digital mammograms from 560 cases and compared favorably with the Hologic R2CAD ImageChecker, one of the most widespread commercial CADe systems. In particular, at the same lesion sensitivity of R2CAD (90%) on biopsy proven malignant cases, CasCADe and R2CAD detected 0.13 and 0.21 false positives per image (FPpi), respectively (p-value=0.09), whereas at the same FPpi of R2CAD (0.21), CasCADe and R2CAD detected 93% and 90% of true lesions respectively (p-value=0.11) thus showing that CasCADe can compete with high-end CADe commercial systems. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Surface free energy of CrN x films deposited using closed field unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Sun, C.-C.; Lee, S.-C.; Dai, S.-B.; Fu, Y.-S.; Wang, Y.-C.; Lee, Y.-H.

    2006-01-01

    CrN x thin films have attracted much attention for semiconductor IC packaging molding dies and forming tools due to their excellent hardness, thermal stability and non-sticking properties (low surface free energy). However, few data has been published on the surface free energy (SFE) of CrN x films at temperatures in the range 20-170 deg. C. In this study CrN x thin films with CrN, Cr(N), Cr 2 N (and mixture of these phases) were prepared using closed field unbalanced magnetron sputtering at a wide range of Cr +2 emission intensity. The contact angles of water, di-iodomethane and ethylene glycol on the coated surfaces were measured at temperatures in the range 20-170 deg. C using a Dataphysics OCA-20 contact angle analyzer. The surface free energy of the CrN x films and their components (e.g., dispersion, polar) were calculated using the Owens-Wendt geometric mean approach. The influences of CrN x film surface roughness and microstructure on the surface free energy were investigated by atomic force microscopy (AFM) and X-ray diffraction (XRD), respectively. The experimental results showed that the lowest total SFE was obtained corresponding to CrN at temperature in 20 deg. C. This is lower than that of Cr(N), Cr 2 N (and mixture of these phases). The total SFE, dispersive SFE and polar SFE of CrN x films decreased with increasing surface temperature. The film roughness has an obvious effect on the SFE and there is tendency for the SFE to increase with increasing film surface roughness

  9. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

  10. Patent pools: Intellectual property rights and competition.

    NARCIS (Netherlands)

    Rodriguez, V.F.

    2010-01-01

    Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

  11. Efficient pooling designs for library screening

    OpenAIRE

    Bruno, William J.; Knill, Emanuel; Balding, David J.; Bruce, D. C.; Doggett, N. A.; Sawhill, W. W.; Stallings, R. L.; Whittaker, Craig C.; Torney, David C.

    1994-01-01

    We describe efficient methods for screening clone libraries, based on pooling schemes which we call ``random $k$-sets designs''. In these designs, the pools in which any clone occurs are equally likely to be any possible selection of $k$ from the $v$ pools. The values of $k$ and $v$ can be chosen to optimize desirable properties. Random $k$-sets designs have substantial advantages over alternative pooling schemes: they are efficient, flexible, easy to specify, require fewer pools, and have er...

  12. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  13. Sculpting the Barnyard Gene Pool

    Science.gov (United States)

    Childers, Gina; Wolfe, Kim; Dupree, Alan; Young, Sheila; Caver, Jessica; Quintanilla, Ruby; Thornton, Laura

    2016-01-01

    Project-based learning (PBL) takes student engagement to a higher level through reflective collaboration, inquiry, critical thinking, problem solving, and personal relevance. This article explains how six high school teachers developed an interconnected, interdisciplinary STEM-focused PBL called "Sculpting the Barnyard Gene Pool." The…

  14. Nanostructure transition in Cr–C–N coatings deposited by pulsed closed field unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Wu, Z.L.; Lin, J.; Moore, J.J.; Lei, M.K.

    2012-01-01

    Cr–C–N coatings with different compositions, i.e. (C + N)/Cr atomic ratios (x) of 0.81–2.77, were deposited using pulsed closed field unbalanced magnetron sputtering by varying the chromium and graphite target powers, the pulse configuration and the ratio of the nitrogen flow rate to the total gas flow rate. Three kinds of nanostructures were identified in the Cr–C–N coatings dependent on the x values: a nano-columnar structure of hexagonal closed-packed (hcp) Cr 2 (C,N) and face-centered cubic (fcc) Cr(C,N) at x = 0.81 and 1.03 respectively, a nanocomposite structure consisting of nanocrystalline Cr(C,N) embedded in an amorphous C(N) matrix at x = 1.26 and 1.78, and a Cr-containing amorphous C(N) structure at x = 2.77. A maximum hardness of 31.0 GPa and a high H/E ratio of 1.0 have been achieved in the nc-Cr(C,N)/a-C(N) nanocomposite structure at x = 1.26, whereas the coating with a Cr-containing amorphous C(N) structure had a minimum hardness of 10.9 GPa and a low H/E ratio of 0.08 at x = 2.77. The incorporation of carbon into the Cr–N coatings led to a phase transition from hcp-Cr 2 (C,N) to fcc-Cr(C,N) by the dissolution into the nanocrystallites, and promoted the amorphization of Cr–C–N coatings with the precipitation of amorphous C(N). It was found that a high x value over 1.0 in the Cr–C–N coatings is the composition threshold to the nanostructure transition. - Highlights: ► Nanostructure transition of Cr–C–N coatings depended on (C + N)/Cr atomic ratio. ► A nano-columnar structure formed at atomic ratio less than 1.0. ► A nc-Cr(C,N)/a-C(N) nanocomposite structure formed at atomic ratio of 1.0–2.7. ► A Cr-containing amorphous C(N) structure formed at atomic ratio more than 2.7. ► Maximum hardness of 31.0 GPa was for nanocomposite coatings at atomic ratio of 1.26.

  15. Analysis of hourly crash likelihood using unbalanced panel data mixed logit model and real-time driving environmental big data.

    Science.gov (United States)

    Chen, Feng; Chen, Suren; Ma, Xiaoxiang

    2018-06-01

    Driving environment, including road surface conditions and traffic states, often changes over time and influences crash probability considerably. It becomes stretched for traditional crash frequency models developed in large temporal scales to capture the time-varying characteristics of these factors, which may cause substantial loss of critical driving environmental information on crash prediction. Crash prediction models with refined temporal data (hourly records) are developed to characterize the time-varying nature of these contributing factors. Unbalanced panel data mixed logit models are developed to analyze hourly crash likelihood of highway segments. The refined temporal driving environmental data, including road surface and traffic condition, obtained from the Road Weather Information System (RWIS), are incorporated into the models. Model estimation results indicate that the traffic speed, traffic volume, curvature and chemically wet road surface indicator are better modeled as random parameters. The estimation results of the mixed logit models based on unbalanced panel data show that there are a number of factors related to crash likelihood on I-25. Specifically, weekend indicator, November indicator, low speed limit and long remaining service life of rutting indicator are found to increase crash likelihood, while 5-am indicator and number of merging ramps per lane per mile are found to decrease crash likelihood. The study underscores and confirms the unique and significant impacts on crash imposed by the real-time weather, road surface, and traffic conditions. With the unbalanced panel data structure, the rich information from real-time driving environmental big data can be well incorporated. Copyright © 2018 National Safety Council and Elsevier Ltd. All rights reserved.

  16. Transient analysis of unbalanced short circuits of the ERDA-NASA 100 kW wind turbine alternator

    Science.gov (United States)

    Hwang, H. H.; Gilbert, L. J.

    1976-01-01

    Unbalanced short-circuit faults on the alternator of the ERDA-NASA Mod-O100-kW experimental wind turbine are studied. For each case, complete solutions for armature, field, and damper-circuit currents; short-circuit torque; and open-phase voltage are derived directly by a mathematical analysis. Formulated results are tabulated. For the Mod-O wind turbine alternator, numerical calculations are given, and results are presented by graphs. Comparisons for significant points among the more important cases are summarized. For these cases the transients are found to be potentially severe. The effect of the alternator neutral-to-ground impedance is evaluated.

  17. Fault Ride Though Control of Photovoltaic Grid-connected Inverter with Current-limited Capability under Offshore Unbalanced Voltage Conditions

    DEFF Research Database (Denmark)

    Liu, Wenzhao; Guo, Xiaoqiang; Savaghebi, Mehdi

    2016-01-01

    The photovoltaic (PV) inverter installed on board experiences the excessive current stress in case of the offshore unbalanced voltage fault ride through (FRT), which significantly affects the operation reliability of the power supply system. In order to solve the problem, the inherent mechanism...... of the excessive current phenomenon with the conventional fault ride through control is discussed. The quantitative analysis of the current peak value is conducted and a new current-limiting control strategy is proposed to achieve the flexible power control and successful fault ride through in a safe current...

  18. Flexible Power Regulation and Current-limited Control of Grid-connected Inverter under Unbalanced Grid Voltage Faults

    DEFF Research Database (Denmark)

    Guo, Xiaoqiang; Liu, Wenzhao; Lu, Zhigang

    2017-01-01

    The grid-connected inverters may experience excessive current stress in case of unbalanced grid voltage Fault Ride Through (FRT), which significantly affects the reliability of the power supply system. In order to solve the problem, the inherent mechanisms of the excessive current phenomenon...... with the conventional FRT solutions are discussed. The quantitative analysis of three phase current peak values are conducted and a novel current-limited control strategy is proposed to achieve the flexible active and reactive power regulation and successful FRT in a safe current operation area with the aim...

  19. Trisomy 2q11.2-->q21.1 resulting from an unbalanced insertion in two generations.

    Science.gov (United States)

    Glass, I A; Stormer, P; Oei, P T; Hacking, E; Cotter, P D

    1998-01-01

    In this communication, we describe two cases of proximal 2q trisomy (2q11.2--> q21.1) resulting from an interchromosomal insertion. The chromosomal origin of the insertion was confirmed by fluorescence in situ hybridisation. An unbalanced karyotype, 46,XX,der(8) ,ins(8;2) (p21.3; q21.1q11.2), was found in the proband and her mother, who both have mild mental retardation, short stature, dysmorphic features, insulin dependent diabetes mellitus, and a psychotic illness. This family is a rare example of direct transmission of a partial autosomal trisomy. Images PMID:9598728

  20. "Ripples" in an Aluminum Pool?

    Science.gov (United States)

    Rohr, James; Wang, Si-Yin; Nesterenko, Vitali F.

    2018-05-01

    Our motivation for this article is for students to realize that opportunities for discovery are all around them. Discoveries that can still puzzle present day researchers. Here we explore an observation by a middle school student concerning the production of what appears to be water-like "ripples" produced in aluminum foil when placed between two colliding spheres. We both applaud and explore the student's reasoning that the ripples were formed in a melted aluminum pool.

  1. Sustainability of common pool resources.

    Science.gov (United States)

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepalese areas: (i) rural (non-capitalistic) and (ii) urban (capitalistic) areas. We find that a proportion of prosocial individuals in urban areas is lower than that in rural areas, and urban residents deplete resources more quickly than rural residents. The composition of proself and prosocial individuals in a group and the degree of capitalism are crucial in that an increase in prosocial members in a group and the rural dummy positively affect resource sustainability by 65% and 63%, respectively. Overall, this paper shows that when societies move toward more capitalistic environments, the sustainability of common pool resources tends to decrease with the changes in individual preferences, social norms, customs and views to others through human interactions. This result implies that individuals may be losing their coordination abilities for social dilemmas of resource sustainability in capitalistic societies.

  2. Flashing oscillation in pool water

    International Nuclear Information System (INIS)

    Takamasa, Tomoji; Kondo, Koichi; Hazuku, Tatsuya

    1996-01-01

    This paper presents an experimental study of high-pressure saturated water discharging into the pool water. The purpose of the experiment is to clarify the phenomena that occur in blow-down of high-pressure saturated water from the pressure vessel into the water-filled containment in the case of a wall-crack accident or a LOCA in an advanced reactor. The results revealed that a flashing oscillation (FO) occurs when high-pressure saturated water discharges into the pool water, under specified experimental settings. The range of the flashing oscillates between a point very close to and some distance from the vent hole. The pressures in the vent tube and pool water vary according to the flashing oscillation. The pressure oscillation and frequency of flashing position might be caused by the balancing action between the supply of saturated water, flashing at the control volume and its condensation on the steam-water interface. A linear analysis was conducted using a spherical flashing bubble model. The period of the flashing oscillation in the experiments can be explained by theoretical analysis

  3. Pressure supression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-10-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model developed in this work produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing is verified by comparing the model-predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  4. Pressure suppression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-01-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  5. Compensación de potencia reactiva mediante bancos asimétricos de capacitores; Reactive Power Compensation by Unbalanced Capacitor Banks

    Directory of Open Access Journals (Sweden)

    Ignacio Pérez Abril

    2011-02-01

    Full Text Available A pesar de que los sistemas de distribución primaria y secundaria son desbalanceados por naturaleza, lacompensación de potencia reactiva en estos sistemas, se realiza comúnmente mediante bancos decondensadores trifásicos balanceados. En este trabajo se presenta la formulación general para el problemade compensación de potencia reactiva en sistemas desbalanceados mediante bancos de condensadoresdesbalanceados. Se presentan cuatro ejemplos de compensación en el secundario de bancos desbalanceadosde transformadores monofásicos. Todos los ejemplos muestran que la compensación por bancosdesbalanceados de capacitores incrementa los beneficios con respecto al uso de bancos balanceados  In spite of the fact that primary and secondary distribution systems are unbalanced by nature, thereactive power compensation on these systems is commonly developed by the use of balanced capacitorbanks. In this paper, the general formulation for the reactive power compensation problem onunbalanced systems with unbalanced capacitor banks is developed. Four examples of reactive powercompensation on the secondary of unbalanced three-phase transformers banks are presented. All theexamples show that the compensation by unbalanced capacitor banks increases the active power lossessaving as well as reduce the transformer’s load and contributes to balance the line currents when the loadis unbalanced.

  6. Unbalanced international collaboration affects adversely the usefulness of countries' scientific output as well as their technological and social impact.

    Science.gov (United States)

    Zanotto, Sonia R; Haeffner, Cristina; Guimarães, Jorge A

    The unbalanced international scientific collaboration as cause of misleading information on the country's contribution to the scientific world output was analyzed. ESI Data Base (Thomson Reuters' InCites), covering the scientific production of 217 active countries in the period 2010-2014 was used. International collaboration implicates in a high percentage (33.1 %) of double-counted world articles, thus impacting qualitative data as citations, impact and impact relative to word. The countries were divided into three groups, according to their individual contribution to the world publications: Group I (24 countries, at least 1 %) representing 83.9 % of the total double-counted world articles. Group II (40 countries, 0.1-0.99 % each). Group III, 153 countries (70.5 %) with international collaboration were: Group I, 43.0 %; Group II, 55.8 % and Group III, 85.2 %. We concluded that very high and unbalanced international collaboration, as presented by many countries, misrepresent the importance of their scientific production, technological and social outputs. Furthermore, it jeopardizes qualitative outputs of the countries themselves, artificially increasing their scientific impact, affecting all fields and therefore, the whole world. The data confirm that when dealing with the qualitative contribution of countries, it is necessary to take in consideration the level of international cooperation because, as seen here, it can and in fact it does create false impression of the real contribution of countries.

  7. Harmonic Injection-Based Power Fluctuation Control of Three-Phase PV Systems under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Nian-Cheng Zhou

    2015-02-01

    Full Text Available Unbalanced voltage will inevitably cause power and DC voltage fluctuations in a three-phase PV system. The deterioration of power quality will do great harm to the PV panels and the loads, so it is necessary to suppress the power fluctuations. This paper further explores the coefficients control strategy of PV converters under unbalanced voltage conditions, aiming to suppress power fluctuations by controlling the injection of some specific orders of current harmonics into the grid. In order to achieve this, the current reference of the PV inverter has been changed by bringing in two control coefficients, and the expression of each order of the current harmonics has been deduced. Based on the standards of PV systems, the regions from which the coefficients can be selected are determined. Then, by tuning these coefficients in the feasible regions, the output parameters (power fluctuation, current THD and odd harmonics can be controlled precisely. The model of this method is built and simulated in PSCAD/EMTDC, and as a result, it is shown that the power fluctuations can be restricted according to different power quality requirements.

  8. Speed Control of Matrix Converter-Fed Five-Phase Permanent Magnet Synchronous Motors under Unbalanced Voltages

    Directory of Open Access Journals (Sweden)

    Borzou Yousefi

    2017-09-01

    Full Text Available Five-phase permanent magnet synchronous motors (PMSM have special applications in which highly accurate speed and torque control of the motor are a strong requirement. Direct Torque Control (DTC is a suitable method for the driver structure of these motors. If in this method, instead of using a common five-phase voltage source inverter, a three-phase to five-phase matrix converter is used, the low-frequency current harmonics and the high torque ripple are limited, and an improved input power factor is obtained. Because the input voltages of such converters are directly supplied by input three-phase supply voltages, an imbalance in the voltages will cause problems such as unbalanced stator currents and electromagnetic torque fluctuations. In this paper, a new method is introduced to remove speed and torque oscillator factors. For this purpose, motor torque equations were developed and the oscillation components created by the unbalanced source voltage, determined. Then, using the active and reactive power reference generator, the controller power reference was adjusted in such a way that the electromagnetic torque of the motor did not change. By this means, a number of features including speed, torque, and flux of the motor were improved in terms of the above-mentioned conditions. Simulations were analyzed using Matlab/Simulink software.

  9. Integral Plus Resonant Sliding Mode Direct Power Control for VSC-HVDC Systems under Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    Weipeng Yang

    2017-10-01

    Full Text Available An integral plus resonant sliding mode direct power control (IRSMC DPC strategy for voltage source converter high voltage direct current (VSC-HVDC systems under unbalanced grid voltage conditions is proposed in this paper. Through detailed instantaneous power flow analysis, a generalized power compensation method, by which the ratio between the amplitude of active and reactive power ripples can be controlled continuously, is obtained. This enables the system to provide flexible power control, so that the desired performance of the system on both the ac and dc sides can be attained under different operating conditions. When the grid voltage is unbalanced, one or both of the active and reactive power terms contain ripples, oscillating at twice the grid frequency, to obtain non-distorted ac current. A power controller consisting of the proportional, integral and resonant control laws is designed using the sliding mode control approach, to achieve accurate power control objective. Simulation studies on a two-terminal VSC-HVDC system using MATLAB/SIMULINK (R2013b, Mathworks, Natick, MA, USA are conducted to verify the effectiveness of the IRSMC DPC strategy. The results show that this strategy ensures satisfactory performance of the system over a wide range of operating conditions.

  10. CDC Study Finds Fecal Contamination in Pools

    Science.gov (United States)

    ... Communication (404) 639-3286 CDC study finds fecal contamination in pools A study of public pools done ... The E. coli is a marker for fecal contamination. Finding a high percentage of E. coli-positive ...

  11. An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions

    DEFF Research Database (Denmark)

    Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz

    2017-01-01

    In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions....... It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method...... is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed...

  12. 1968 Listing of Swimming Pool Equipment.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

    An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

  13. Clinical blood pool MR Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leiner, Tim [Maastrich University Medical Center (Netherlands). Dept. of Radiology; Goyen, Martin [University Medical Center Hamburg-Eppendorf (Germany); Rohrer, Mathias [Bayer Schering Pharma AG, Berlin (Germany). European Business Unit Diagnostic Imaging; Schoenberg, Stefan O. (eds.) [University Hospital Mannheim Medical Faculty Mannheim - Heidelberg Univ. (Germany). Dept. of Clinical Radiology and Nuclear Medicine

    2008-07-01

    Clinical Blood Pool MR Imaging - This excellent treatise on Vasovist {sup registered} created by a team of exceptional faculty who are pioneers in MR Angiography covers the basic techniques, safety, efficacy, image processing and pharmaco-economic details to successfully implement a new level of MRA image quality with this new contrast agent. Martin Prince, Cornell University, New York The editors and authors have made groundbreaking contributions towards establishing MR angiography in various investigative settings, rendering it more precise and applying it for diverse indications. The work presented here is founded upon the extensive experience of the editors, as well as the broad range of experience from other scientific working groups. Maximilian Reiser, Ludwig Maximilian University, Munich Vasovist {sup registered} (Gadofosveset), worldwide the first blood pool agent, has only recently become available for clinical use, but has already gained wide acceptance as a tool to improve magnetic resonance angiography. This book presents the first in-depth introduction to the basic physicochemical aspects of the agent, the application of Vasovist {sup registered} in clinical MRA, as well as potential clinical applications beyond MRA and patient management-related aspects. The first part of the book explains basic and technical properties of the agent and the differences of Vasovist {sup registered} compared to currently available extracellular agents. The second part contains detailed chapters on safety and efficacy. In the third part the focus is on MR angiographic applications, and in the fourth part of the book potential clinical fields beyond MRA are explored. All clinical chapters feature ready-to-use clinical protocols and a series of take home messages that concisely summarize the current role of blood pool imaging for each specific indication. (orig.)

  14. Method of measuring a liquid pool volume

    Science.gov (United States)

    Garcia, G.V.; Carlson, N.M.; Donaldson, A.D.

    1991-03-19

    A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools is disclosed, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figures.

  15. Large-scale pool fires

    Directory of Open Access Journals (Sweden)

    Steinhaus Thomas

    2007-01-01

    Full Text Available A review of research into the burning behavior of large pool fires and fuel spill fires is presented. The features which distinguish such fires from smaller pool fires are mainly associated with the fire dynamics at low source Froude numbers and the radiative interaction with the fire source. In hydrocarbon fires, higher soot levels at increased diameters result in radiation blockage effects around the perimeter of large fire plumes; this yields lower emissive powers and a drastic reduction in the radiative loss fraction; whilst there are simplifying factors with these phenomena, arising from the fact that soot yield can saturate, there are other complications deriving from the intermittency of the behavior, with luminous regions of efficient combustion appearing randomly in the outer surface of the fire according the turbulent fluctuations in the fire plume. Knowledge of the fluid flow instabilities, which lead to the formation of large eddies, is also key to understanding the behavior of large-scale fires. Here modeling tools can be effectively exploited in order to investigate the fluid flow phenomena, including RANS- and LES-based computational fluid dynamics codes. The latter are well-suited to representation of the turbulent motions, but a number of challenges remain with their practical application. Massively-parallel computational resources are likely to be necessary in order to be able to adequately address the complex coupled phenomena to the level of detail that is necessary.

  16. Structural integrity assessment of HANARO pool cover

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    2001-11-01

    This report is for the seismic analysis and the structural integrity evaluation of HANARO Pool Cover in accordances with the requirement of the Technical Specification for Seismic Analysis of HANARO Pool Cover. For performing the seismic analysis and evaluating the structural integrity for HANARO Pool Cover, the finite element analysis model using ANSYS 5.7 was developed and the dynamic characteristics were analyzed. The seismic response spectrum analyses of HANARO Pool Cover under the design floor response spectrum loads of OBE and SSE were performed. The analysis results show that the stress values in HANARO Pool Cover for the seismic loads are within the ASME Code limits. It is also confirmed that the fatigue usage factor is less than 1.0. Therefore any damage on structural integrity is not expected when an HANARO Pool Cover is installed in the upper part of the reactor pool

  17. Improved Power Control Using Optimal Adjustable Coefficients for Three-Phase Photovoltaic Inverter under Unbalanced Grid Voltage

    Science.gov (United States)

    Wang, Qianggang; Zhou, Niancheng; Lou, Xiaoxuan; Chen, Xu

    2014-01-01

    Unbalanced grid faults will lead to several drawbacks in the output power quality of photovoltaic generation (PV) converters, such as power fluctuation, current amplitude swell, and a large quantity of harmonics. The aim of this paper is to propose a flexible AC current generation method by selecting coefficients to overcome these problems in an optimal way. Three coefficients are brought in to tune the output current reference within the required limits of the power quality (the current harmonic distortion, the AC current peak, the power fluctuation, and the DC voltage fluctuation). Through the optimization algorithm, the coefficients can be determined aiming to generate the minimum integrated amplitudes of the active and reactive power references with the constraints of the inverter current and DC voltage fluctuation. Dead-beat controller is utilized to track the optimal current reference in a short period. The method has been verified in PSCAD/EMTDC software. PMID:25243215

  18. ANALYSIS OF THE HARMONIC LOSSES WITH ARTIFICIAL NEURAL NETWORKS IN UNBALANCED SYSTEM LOSSES USING BALANCED ELECTRIC POWER SYSTEM DATA

    Directory of Open Access Journals (Sweden)

    Aslan İNAN

    2005-01-01

    Full Text Available The losses in the power systems should be low as possible as. Saving energy instead of loses (kWh in power utilities can supply much more energy to the consumers. The lower losses the more energy is saved and thus the power system becomes more economical. In recent years, the increasing number of applications and power ratings of the devices which have nonlinear voltage-current characteristics cause voltage waveform distortion and additional losses. While evaluating losses considering harmonics will provide more contribution to obtain more accurate results. In this study, Artificial Neural Networks (ANN method has been presented to predict the harmonic losses in unbalanced power systems by using the data from balanced power system with nonlinear loads.

  19. Origin of unbalanced reaction of vacancies and interstitials during irradiation with cascades and influence on microstructural evolution

    International Nuclear Information System (INIS)

    Kiritani, M.; Yoshiie, T.; Kojima, S.; Satoh, Y.

    1993-01-01

    Based upon the underlying premise that all the microstructure evolution during irradiation results from the asymetrical reaction between vacancies and interstitials, the origin of the asymetry is sought and categorized, and the mechanism of defect structure evolution for each source of asymetry is investigated. The role of neutral sinks and the influence of dislocations are examined for the cases of irradiation with and without cascade damage. Vacancy cluster formation directly from cascades is found to favor the generation of freely migrating interstitials. Stochastic fluctuations of the point defect reactions under the balanced condition of vacancy and interstitial is experimentally detected, and the important role of the fluctuations is found in the determination of the fate of small interstitial cluster embryos produced by cascade damage. The influence of the unbalanced point defect reaction starting from difference in spacial distribution between vacancies and interstitials formed by cascade collisions is discussed as one of the important origins of vacancy dominant reactions. (orig.)

  20. Enhanced Power Quality and Minimized Peak Current Control in An Inverter based Microgrid under Unbalanced Grid Faults

    DEFF Research Database (Denmark)

    Liu, Wenzhao; Guo, Xiaoqiang; Sulligoi, Giorgio

    2016-01-01

    The microgrid inverter experiences the power oscillations and current harmonics in case of the unbalanced grid voltage faults. However, there is a trade-off between power oscillations and current harmonics should be considered in three phase three wire inverter systems during the conventional fault...... ride through control. In order to solve this problem, a novel control strategy is proposed to enhance the output current quality while mitigating the active and reactive output power oscillations. Moreover, a simple current-limited control strategy can be achieved without the necessity of the voltage....../current positive/negative sequence extraction. Finally, the simulation tests of the conventional and proposed control solutions are carried out. The results verify the effectiveness of the proposed strategy....

  1. Effect of unbalanced diets on the long-term metabolism of a toxicant. 1. Lead in rats: preliminary note.

    Science.gov (United States)

    Baldini, M; Coni, E; Mantovani, A; Stacchini, A; Zanasi, F

    1989-01-01

    The aim of this study was the evaluation of the effect of dietary imbalances on absorption and distribution of lead in the female Sprague-Dawley rat. In this note preliminary results on the relationship between blood concentrations of lead and unbalanced diets are presented. Hyperproteic, hyperglycidic, hyperlipidic and balanced diets were prepared, and most of them included 15 mg/kg lead. Blood samples were collected at day 0, 21, 36, and 95 of the diets and analyzed by anodic stripping voltammetry (ASV). Lead uptake as a function of feed consumption was found to decrease in the order: balanced, hyperproteic and hyperglycidic, hyperlipidic diet. On the other hand lead blood levels were as follows (decreasing order): hyperlipidic, hyperproteic, hyperglycidic, balanced. Further research is being carried out on the influences of dietary imbalances on whole-body distribution of lead.

  2. Improved power control using optimal adjustable coefficients for three-phase photovoltaic inverter under unbalanced grid voltage.

    Science.gov (United States)

    Wang, Qianggang; Zhou, Niancheng; Lou, Xiaoxuan; Chen, Xu

    2014-01-01

    Unbalanced grid faults will lead to several drawbacks in the output power quality of photovoltaic generation (PV) converters, such as power fluctuation, current amplitude swell, and a large quantity of harmonics. The aim of this paper is to propose a flexible AC current generation method by selecting coefficients to overcome these problems in an optimal way. Three coefficients are brought in to tune the output current reference within the required limits of the power quality (the current harmonic distortion, the AC current peak, the power fluctuation, and the DC voltage fluctuation). Through the optimization algorithm, the coefficients can be determined aiming to generate the minimum integrated amplitudes of the active and reactive power references with the constraints of the inverter current and DC voltage fluctuation. Dead-beat controller is utilized to track the optimal current reference in a short period. The method has been verified in PSCAD/EMTDC software.

  3. Detecting mode hopping in single-longitudinal-mode fiber ring lasers based on an unbalanced fiber Michelson interferometer.

    Science.gov (United States)

    Ma, Mingxiang; Hu, Zhengliang; Xu, Pan; Wang, Wei; Hu, Yongming

    2012-10-20

    A method of detecting mode hopping for single-longitudinal-mode (SLM) fiber ring lasers has been proposed and experimentally demonstrated. The method that is based on an unbalanced Michelson interferometer (MI) utilizing phase generated carrier modulation instantly transforms mode-hopping dynamics into steep phase changes of the interferometer. Multiform mode hops in an SLM erbium-doped fiber ring laser with an 18.6 MHz mode spacing have been detected exactly in real-time domain and discussed in detail. Numerical results show that the MI-based method has a high testing sensitivity for identifying mode hopping, which will play a significant role in evaluating the output stability of SLM fiber lasers.

  4. Livermore pool-type reactor

    International Nuclear Information System (INIS)

    Mann, L.G.

    1977-01-01

    The Livermore Pool-Type Reactor (LPTR) has served a dual purpose since 1958--as an instrument for fundamental research and as a tool for measurement and calibration. Our early efforts centered on neutron-diffraction, fission, and capture gamma-ray studies. During the 1960's it was used for extensive calibration work associated with radiochemical and physical measurements on nuclear-explosive tests. Since 1970 the principal applications have been for trace-element measurements and radiation-damage studies. Today's research program is dominated by radiochemical studies of the shorter-lived fission products and by research on the mechanisms of radiation damage. Trace-element measurement for the National Uranium Resource Evaluation (NURE) program is the major measurement application today

  5. Cardiac blood pool emission tomography

    International Nuclear Information System (INIS)

    Itti, R.; Philippe, L.; Lorgeron, J.M.; Charbonnier, B.; Raynaud, P.; Brochier, M.

    1983-01-01

    After blood pool labeling using technetium-99m, a series of cardiac pictures is acquired during the rotation of a gamma-camera about the patient. Computer processing leads to reconstruction of various tomographic slices from the original planar projection. Electrocardiographic gating selects the different phases of the cardiac cycle. Individual slices through the left ventricular region are added in order to provide ''thick'' slices on which global and regional parameters of the left ventricular function can be determined. Due to the proportionality existing between count rates and labeled blood volumes, any geometrical model can be avoided. The delineation of regions of interest for count integration is made easier due to the absence of superimposition of structures; no correction for background is necessary. Tomography thus appears to be more consistent and more accurate than the classical methods using planar projections. In addition, right ventricular morphological and kinetic studies can be performed in the same conditions as for the left ventricle [fr

  6. Arc-weld pool interactions

    International Nuclear Information System (INIS)

    Glickstein, S.S.

    1978-08-01

    The mechanisms involved in arc-weld pool interactions are extremely complex and no complete theory is presently available to describe much of the phenomena observed during welding. For the past several years, experimental and analytical studies have been undertaken at the Bettis Atomic Power Laboratory to increase basic understanding of the gas tungsten arc welding process. These studies have included experimental spectral analysis of the arc in order to determine arc temperature and analytical modeling of the arc and weld puddle. The investigations have been directed toward determining the cause and effects of variations in the energy distribution incident upon the weldment. In addition, the effect of weld puddle distortion on weld penetration was investigated, and experimental and analytical studies of weld process variables have been undertaken to determine the effects of the variables upon weld penetration and configuration. A review of the results and analysis of these studies are presented

  7. Neutron activation analysis in the central nervous system tissues of neurological diseases and rats maintained on minerally unbalanced diets

    International Nuclear Information System (INIS)

    Yasui, Masayuki; Ota, Kiichiro; Sasajima, Kazuhisa.

    1995-01-01

    Epidemiological surveys on Guam have suggested that low calcium (Ca), magnesium (Mg) and high Al and Mn in river, soil and drinking water may be implicated in the pathogenesis of PD. Experimentally, low Ca-Mg diets with or without added Al have been found to accelerate Al deposition in the CNS of rats and monkeys. Although excessive deposition of Mn produces neurotoxic action similar to Al in CNS tissues, the mechanism of Mn deposition coupled with Al loading in the presence of low Ca-Mg intake is not yet known. In this animal study, the deposition and metal-metal interaction of both Al and Mn in the CNS, visceral organs and bones of rats fed unbalanced mineral diets were analyzed. Male Wistar rats, weighing 200 g, were maintained for 90 days on the following diets: (A) standard diet, (B) low Ca diet, (C) low Ca-Mg diet, (D) low Ca-Mg diet with high Al. Al and Mn content were determined in the frontal cortex, spinal cord, kidney, muscle, abdominal aorta, femur and lumbar spine using neutron activation analysis (NAA). Intake of low Ca and Mg with added Al in rats led to the high concentrations of Mn and Al in bones and in the frontal cortex. It is likely that unbalanced mineral diets and metal-metal interactions may lead to the unequal distribution of Al and Mn in bones and ultimately in the CNS inducing CNS degeneration. On the other hand, concentrations of copper (Cu), calcium (Ca) and aluminum (Al) for 26 subanatomical regions of the CNS were measured by neutron activation analysis (NAA) in two cases of Wilson's disease, two of portal systemic encephalopathy, six pathologically verified cases of ALS, four of Parkinson's disease and five neurologically normal controls. Also zinc (Zn) and iron (Fe) concentrations were measured by NAA for frontal and occipital lobes of parkinsonism-dementia. (author)

  8. De novo unbalanced translocation (4p duplication/8p deletion) in a patient with autism, OCD, and overgrowth syndrome.

    Science.gov (United States)

    Sagar, Angela; Pinto, Dalila; Najjar, Fedra; Guter, Stephen J; Macmillan, Carol; Cook, Edwin H

    2017-06-01

    Chromosomal abnormalities, such as unbalanced translocations and copy number variants (CNVs), are found in autism spectrum disorders (ASDs) [Sanders et al. (2011) Neuron 70: 863-885]. Many chromosomal abnormalities, including sub microscopic genomic deletions and duplications, are missed by G-banded karyotyping or Fragile X screening alone and are picked up by chromosomal microarrays [Shen et al. (2010) Pediatrics 125: e727-735]. Translocations involving chromosomes 4 and 8 are possibly the second most frequent translocation in humans and are often undetected in routine cytogenetics [Giglio et al. (2002) Circulation 102: 432-437]. Deletions of 4p16 have been associated with Wolf-Hirschhorn syndrome while 4p16 duplications have been associated with an overgrowth syndrome and mild to moderate mental retardation [Partington et al. (1997) Journal of Medical Genetics 34: 719-728]. The 8p23.3 region contains the autism candidate gene DLGAP2, which can contribute to autism when disrupted [Marshall et al. (2008) The American Journal of Human Genetics 82: 477-488] . There has been a case report of a family with autism spectrum disorder (ASD), prominent obsessional behavior, and overgrowth in patients with der (8) t (4;8) p (16;23) [Partington et al. (1997)]. This is an independent report of a male patient with autism, obsessive compulsive disorder (OCD), attention-deficit hyperactivity disorder (ADHD), and an overgrowth syndrome, whose de novo unbalanced translocation der (8) t (4;8) p (16.1→ter; 23.1→ter) was initially missed by routine cytogenetics but detected with SNP microarray, allowing higher resolution of translocation breakpoints. © 2017 Wiley Periodicals, Inc.

  9. Harmonic Distortion Performance of Multi Three-Phase SCR-Fed Drive Systems with Controlled DC-Link Current under Unbalanced Grid

    DEFF Research Database (Denmark)

    Soltani, Hamid; Davari, Pooya; Blaabjerg, Frede

    2017-01-01

    . In this paper, the main aim is to analyze the effects of the grid unbalanced voltage on the multi-unit three-phase ASDs with the Silicon-Controlled Rectifier (SCR)-fed front-end rectifiers, where the DC-link current is controlled utilizing an Electronic Inductor (EI) technique. In this respect, the main...

  10. Peripheral blood mononuclear cells as a source to detect markers of homeostatic alterations caused by the intake of diets with an unbalanced macronutrient composition

    NARCIS (Netherlands)

    Diaz-Rua, R.; Keijer, J.; Caimari, A.; Schothorst, van E.M.; Oliver, P.; Palou, A.

    2015-01-01

    Peripheral blood mononuclear cells (PBMC) are accessible in humans and their gene expression pattern was shown to reflect overall physiological response of the body to a specific stimulus, such as diet. We aimed to study the impact of sustained intake (4 months) of diets with an unbalanced

  11. Unique unbalanced X;X translocation (Xq22;p11.2) in a woman with primary amenorrhea but without Ullrich-Turner syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Letterie, G.S. [Virginia Mason Medical Center, Seattle, WA (United States)

    1995-12-04

    This is a report of a patient with delayed puberty and a previously unreported translocation 46,X,-X,+der(X),t(X;X) (q22;p11.2) without any manifestations of Ullrich-Turner syndrome. The relationship of this unbalanced translocation to the critical region hypothesis is discussed. 6 refs., 3 figs.

  12. New control strategy of stand-alone brushless doubly-fed induction generator for supplying unbalanced loads in ship shaft power generation system

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The ship shaft power generation system based on a stand-alone brushless doubly-fed induction generator (BDFIG) have demonstrated excellent saving-energy performance. This paper presents a new control scheme of the stand-alone BDFIG for supplying unbalanced loads in the ship shaft power generation...

  13. Balanced vs unbalanced crystalloid resuscitation in a near-fatal model of hemorrhagic shock and the effects on renal oxygenation, oxidative stress and inflammation

    NARCIS (Netherlands)

    Aksu, Ugur; Bezemer, R.; Yavuz, B.; Kandil, Asli; Demirci, C.; Ince, C.

    2012-01-01

    Background: The aim of the present study was to test the hypothesis that balanced crystalloid resuscitation would be better for the kidney than unbalanced crystalloid resuscitation in a rat hemorrhagic shock model. Methods: Male Wistar rats were randomly assigned to four groups (n = 6/group): (1)

  14. Control Method for DC-Link Voltage Ripple Cancellation in Voltage Source Inverter under Unbalanced Three-Phase Voltage Supply Conditions

    Czech Academy of Sciences Publication Activity Database

    Chomát, Miroslav; Schreier, Luděk

    2005-01-01

    Roč. 152, č. 3 (2005), s. 494-500 ISSN 1350-2352 R&D Projects: GA ČR(CZ) GA102/02/0554 Institutional research plan: CEZ:AV0Z20570509 Keywords : DC-link voltage * unbalanced three-phase voltage Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.587, year: 2005

  15. Control of grid integrated voltage source converters under unbalanced conditions: development of an on-line frequency-adaptive virtual flux-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Suul, Jon Are

    2012-03-15

    Three-Phase Voltage Source Converters (VSCs) are finding widespread applications in grid integrated power conversion systems. The control systems of such VSCs are in an increasing number of these applications required to operate during voltage disturbances and unbalanced conditions. Control systems designed for grid side voltagesensor-less operation are at the same time becoming attractive due to the continuous drive for cost reduction and increased reliability of VSCs, but are not commonly applied for operation during unbalanced conditions. Methods for voltage-sensor-less grid synchronization and control of VSCs under unbalanced grid voltage conditions will therefore be the main focus of this Thesis. Estimation methods based on the concept of Virtual Flux, considering the integral of the converter voltage in analogy to the flux of an electric machine, are among the simplest and most well known techniques for achieving voltage-sensor-less grid synchronization. Most of the established techniques for Virtual Flux estimation are, however, either sensitive to grid frequency variations or they are not easily adaptable for operation under unbalanced grid voltage conditions. This Thesis addresses both these issues by proposing a simple approach for Virtual Flux estimation by utilizing a frequency-adaptive filter based on a Second Order Generalized Integrator (SOGI). The proposed approach can be used to achieve on-line frequency-adaptive varieties of conventional strategies for Virtual Flux estimation. The main advantage is, however, that the SOGI-based Virtual Flux estimation can be arranged in a structure that achieves inherent symmetrical component sequence separation under unbalanced conditions. The proposed method for Virtual Flux estimation can be used as a general basis for voltage-sensor-less grid synchronization and control during unbalanced conditions. In this Thesis, the estimated Virtual Flux signals are used to develop a flexible strategy for control of active

  16. Guide for decontaminating swimming pool at schools

    International Nuclear Information System (INIS)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-01

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  17. Current operating practices of nuclear insurance pools

    International Nuclear Information System (INIS)

    O'Connell, J.M.

    1993-01-01

    This paper discusses the nuclear pooling system and co-operation between the pools, present practice and capacity, with a breakdown of the limits for third party liability and material damage. The author also describes the relationship between the pools and the nuclear operators (the policyholders), and concludes that the nuclear pools have been successful in serving the interests of their member companies, their policyholders and the governments as they have provided a stable insurance market by making available capacity in amounts that had never before been assembled and placed at risk in a single location. 2 tabs

  18. Guide for decontaminating swimming pool at schools

    Energy Technology Data Exchange (ETDEWEB)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-15

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  19. Structure for nuclear fuel storage pools

    International Nuclear Information System (INIS)

    Ebata, Sakae; Nichiei, Shinji.

    1979-01-01

    Purpose: To enable leak detection in nuclear fuel storage pools, as well as prevent external leakages while keeping the strength of the constructional structures. Constitution: Protection plates are provided around pool linear plates and a leak reception is provided to the bottom. Leakages are detected by leak detecting pipeways and the external leakages are prevented by collecting them in a detection area provided in the intermediate layer. Since ferro-reinforcements at the bottom wall of the pool are disconnected by the protection plate making it impossible to form the constructional body, body hunches are provided to the bottom wall of the pool for processing the ferro-reinforcements. (Yoshino, Y.)

  20. Heat transfer from internally heated hemispherical pools

    International Nuclear Information System (INIS)

    Gabor, J.D.; Ellsion, P.G.; Cassulo, J.C.

    1980-01-01

    Experiments were conducted on heat transfer from internally heated ZnSO 4 -H 2 O pools to the walls of hemispherical containers. This experimental technique provides data for a heat transfer system that has to date been only theoretically treated. Three different sizes of copper hemispherical containers were used: 240, 280, 320 mm in diameter. The pool container served both as a heat transfer surface and as an electrode. The opposing electrode was a copper disk, 50 mm in diameter located at the top of the pool in the center. The top surface of the pool was open to the atmosphere

  1. Oxidation kinetics of corium pool

    Energy Technology Data Exchange (ETDEWEB)

    Sulatsky, A.A., E-mail: andrei314@mail.ru [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Smirnov, S.A. [D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), St. Petersburg (Russian Federation); Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Fischer, M.; Hellmann, S. [AREVA NP GmbH, Erlangen (Germany); Tromm, W.; Miassoedov, A. [Forschungzentrum Karlsruhe (FZK), Karlsruhe (Germany); Bottomley, D. [EUROPÄISCHE KOMMISSION, Joint Research Centre Institut für Transurane (ITU), Karlsruhe (Germany); Piluso, P. [CEA Cadarache-DEN/DTN/STRI, St.Paul-lez-Durance (France); Barrachin, M. [Institut de Radioprotection et Sûreté Nucléaire, St.Paul-lez-Durance (France)

    2013-09-15

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations.

  2. Oxidation kinetics of corium pool

    International Nuclear Information System (INIS)

    Sulatsky, A.A.; Smirnov, S.A.; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu.; Fischer, M.; Hellmann, S.; Tromm, W.; Miassoedov, A.; Bottomley, D.; Piluso, P.; Barrachin, M.

    2013-01-01

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations

  3. 13 CFR 120.1708 - Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... United States. (c) SBA purchase of a Loan Interest. SBA will determine whether to purchase a Loan... reserves the right to purchase a Loan Interest from a Pool at any time. (d) Self-liquidating. A Pool... market conditions and program experience, and will publish any such change in the Federal Register. (h...

  4. Compact fuel storage rack for fuel pools

    International Nuclear Information System (INIS)

    Parras, F.; Louvat, J.P.

    1986-01-01

    ETS LEMER and FRAMATOME propose a new compact storage rack. This rack permits a considerable increase of the storage capacity of cooling pools. A short description of the structure and the components is presented, to propose racks that are: . Inalterable, . Compact, . Insensitive to earthquakes. Installation in pools already in operation is simplified by their light structure and the bearing device [fr

  5. The warm pool in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shetye, S.R.

    is larger and warmer, a peculiarity of the pool in the Indian Ocean is its seasonal variation. The surface area of the pool changes from 24 x 106 km2 in April to 8 x 106 km2 in September due to interaction with the southwest monsoon. The annual cycles of sea...

  6. Shedding Light on Dark Liquidity Pools

    NARCIS (Netherlands)

    Degryse, H.A.; van Achter, M.; Wuyts, G.

    2008-01-01

    This article reviews the recent developments on dark liquidity pools starting from the theoretical and empirical academic literature. The number of dark liquidity pools as well as their trading volume has grown substantially in the last couple of years. We highlight the incentives of providers as

  7. Big city consultants shut down our pool : a shocking community pool gets checked for stray voltage

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, P. [Power Line Systems Engineering Inc., Markham, ON (Canada)

    2009-12-15

    This article discussed an investigation conducted at a community pool where swimmers complained of receiving electrical shocks both in the pool and on the pool's deck area. Electrical measurements taken at the pool revealed current flows from the pool water to various points around the deck area. Measured current flow in the pool area was 30 amps even when the main pool service breaker was opened to shut off power to the entire facility. Thirty amps of primary neutral current was then measured on the primary side aerial neutral in front of the pool. A 10 amp primary feeder from the pool joined up with the complex's primary neutral wire to increase the neutral current to 40 amps. The combined 40 amps current then returned to the secondary side of a nearby utility transformer substation. The study showed that the underground wet low-resistance grounded surface area of the pool was attracting the 30 amps of utility current from the surrounding ground area. The local utility disconnected the primary and secondary neutral interconnection at the pool's main 600-volt step-down transformer. The pool deck was removed in order to install additional copper bonding grounds. In order to avert serious injuries, many experts propose that all electric utilities should be required by law to reconfigure their power systems to prevent primary power neutral currents from entering private buildings. 1 tab., 2 figs.

  8. Ripples in a superconducting tidal pool

    CERN Document Server

    Hudson, E

    2003-01-01

    The behaviour of electrons in a metal is often compared to that of water in a pool. An empty pool is like a material that has all of its electrons removed. As electrons are 'poured' into the metal, they first occupy the lowest energies available - the bottom of the pool - and eventually fill up to the Fermi energy, the top of the pool. At this point we no longer discuss electrons but quasiparticles. These are electrons that have modified properties due to their interactions within the material. Waves in a pool can be excited, and their properties will depend on the depth of the water. Similarly in a metal, quasiparticles behave like waves that have a material-dependent dispersion relation between their energy and their wavevector, which specifies their direction and wavelength. This simple analogy also hints at an indirect method of measuring the dispersion relation of a metal, and hence the myriad of properties that depend on it. (U.K.)

  9. Design and Construction of Pool Door for Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door.

  10. Design and Construction of Pool Door for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin

    2016-01-01

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door

  11. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  12. Pool scrubbing models for iodine components

    International Nuclear Information System (INIS)

    Fischer, K.

    1996-01-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs

  13. Operation and maintenance techniques of pool and pool water purification system in IMEF

    Energy Technology Data Exchange (ETDEWEB)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs.

  14. Operation and maintenance techniques of pool and pool water purification system in IMEF

    International Nuclear Information System (INIS)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs

  15. Swimming pool hydraulics and their significance for public pools. Bedeutung der Beckenhydraulik in oeffentlichen Schwimmbaedern

    Energy Technology Data Exchange (ETDEWEB)

    Gansloser, G

    1989-11-01

    The term of swimming pool hydraulics means the process of letting in and drawing off water to and from the pool while ensuring that no inadmissible water-borne contaminant concentrations will occur anywhere within the pool. Measurements were performed on a pool to study the significance of correct pool hydraulics. The author points out that a wrong water recirculation design will bring to nought the effects of an elaborate water treatment system; by contrast, poor pool water quality can be greatly improved by redesigning the pool water hydraulics approach. In principle, systems with with water inlet at one side and water outlet at the far side will fall short of hygienic requirements. (BWI).

  16. Studies of thermal stratification in water pool

    International Nuclear Information System (INIS)

    Verma, P.K.; Chandraker, D.K.; Nayak, A.K.; Vijayan, P.K.

    2015-01-01

    Large water pools are used as a heat sink for various cooling systems used in industry. In context of advance nuclear reactors like AHWR, it is used as ultimate heat sink for passive systems for decay heat removal and containment cooling. This system incorporates heat exchangers submerged in the large water pool. However, heat transfer by natural convection in pool poses a problem of thermal stratification. Due to thermal stratification hot layers of water accumulate over the relatively cold one. The heat transfer performance of heat exchanger gets deteriorated as a hot fluid envelops it. In the nuclear reactors, the walls of the pool are made of concrete and it may subject to high temperature due to thermal stratification which is not desirable. In this paper, a concept of employing shrouds around the heat source is studied. These shrouds provide a bulk flow in the water pool, thereby facilitating mixing of hot and cold fluid, which eliminate stratification. The concept has been applied to the a scaled model of Gravity Driven Water Pool (GDWP) of AHWR in which Isolation Condensers (IC) tubes are submerged for decay heat removal of AHWR using ICS and thermal stratification phenomenon was predicted with and without shrouds. To demonstrate the adequacy of the effectiveness of shroud arrangement and to validate the simulation methodology of RELAP5/Mod3.2, experiments has been conducted on a scaled model of the pool with and without shroud. (author)

  17. Spent fuel pool cleanup and stabilization

    International Nuclear Information System (INIS)

    Miller, R.L.

    1987-06-01

    Each of the plutonium production reactors at Hanford had a large water-filled spent fuel pool to provide interim storage of irradiated fuel while awaiting shipment to the separation facilities. After cessation of reactor operations the fuel was removed from the pools and the water levels were drawn down to a 5- to 10-foot depth. The pools were maintained with the water to provide shielding and radiological control. What appeared to be a straightforward project to process the water, remove the sediments from the basin, and stabilize the contamination on the floors and walls became a very complex and time consuming operation. The sediment characteristics varied from pool to pool, the ion exchange system required modification, areas of hard-pack sediments were discovered on the floors, special arrangements to handle and package high dose rate items for shipment were required, and contract problems ensued with the subcontractor. The original schedule to complete the project from preliminary engineering to final stabilization of the pools was 15 months. The actual time required was about 25 months. The original cost estimate to perform the work was $2,651,000. The actual cost of the project was $5,120,000, which included $150,000 for payment of claims to the subcontractor. This paper summarizes the experiences associated with the cleanup and radiological stabilization of the 100-B, -C, -D, and -DR spent fuel pools, and discusses a number of lessons learned items

  18. Nonlinear Dynamic Response of an Unbalanced Flexible Rotor Supported by Elastic Bearings Lubricated with Piezo-Viscous Polar Fluids

    Directory of Open Access Journals (Sweden)

    Mustapha Lahmar

    2015-04-01

    Full Text Available On the basis of the V. K. Stokes micro-continuum theory, the effects of couple stresses on the nonlinear dynamic response of the unbalanced Jeffcott’s flexible rotor supported by layered hydrodynamic journal bearings is presented in this paper. A nonlinear transient modified Reynolds’ equation is derived and discretized by the finite element method to obtain the fluid-film pressure field as well as the film thickness by means of the implicit Euler method. The nonlinear orbits of the rotor center are determined by solving the nonlinear differential equations of motion with the explicit Euler’s scheme taking into account the flexibility of rotor. According to the obtained results, the combined effects of couple stresses due to the presence of polymer additives in lubricant and the pressure dependent viscosity on the nonlinear dynamic response of the rotor-bearing system are significant and cannot be ignored or overlooked. As expected, these effects are more noticeable for polymers characterized by higher length molecular chains.

  19. Microstructure and mechanical properties of Ti–B–C–N–Si nanocomposite films deposited by unbalanced magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jaeho; An, Eunsol; Park, In-Wook; Nam, Dae-Geun [Korea Institute of Industrial Technology (KITECH), Busan, 618-230 (Korea, Republic of); Jo, Ilguk; Lin, Jianliang; Moore, John J. [Advanced Coatings and Surface Engineering Laboratory (ACSEL), Colorado School of Mines, 1500 Illinois St., Golden, Colorado 80401 (United States); Ho Kim, Kwang; Park, Ikmin [School of Materials Science and Engineering, Pusan National University, Busan, 609-735 (Korea, Republic of)

    2013-11-15

    Quinary Ti–B–C–N–Si nanocomposite thin films were deposited on AISI 304 stainless steel substrates by d.c. unbalanced magnetron sputtering from a TiB{sub 2}–TiC compound target and a pure Si target. The relationship between microstructure and mechanical properties of the films was investigated in terms of the nanosized crystallites/amorphous system. The synthesized Ti–B–C–N–Si films were characterized using x-ray diffraction, x-ray photoelectron spectroscopy, atomic force microscopy, and high resolution transmission electron microscopy. The results showed that the Ti–B–C–N–Si films were nanocomposites composed of nanosized TiB{sub 2}, TiC, and TiSi{sub 2} crystallites (2-3 nm in size) embedded in an amorphous matrix. The addition of Si to the Ti–B–C–N film led to precipitation of nanosized crystalline TiSi{sub 2} and percolation of amorphous SiC phases. The Ti–B–C–N–Si films with up to 7 at. % Si content presented high hardness (≥35 GPa), H/E (≥0.0095), and W{sub e} (>50%) with compressive residual stress (∼0.5 GPa). A systematic investigation on the microstructure and mechanical properties of Ti–B–C–N–Si films containing different Si contents is reported.

  20. Unbalanced inflammatory reaction could increase tissue destruction and worsen skin infectious diseases - a comparative study of leishmaniasis and sporotrichosis.

    Science.gov (United States)

    Morgado, F N; de Carvalho, L M V; Leite-Silva, J; Seba, A J; Pimentel, M I F; Fagundes, A; Madeira, M F; Lyra, M R; Oliveira, M M; Schubach, A O; Conceição-Silva, F

    2018-02-13

    The clinical presentations of skin diseases produced by different pathogens, as American tegumentary leishmaniasis (ATL) and sporotrichosis can be similar and possibly influenced by the skin immune system (SIS). The aim of the study was to understand the underlying mechanisms of skin inflammation produced by different pathogens. We used immunohistochemistry to analyze 96 patients: a- localized cutaneous leishmaniasis (LCL-ATL); b- sporotrichoid cutaneous leishmaniasis (SCL-ATL); c-lymphocutaneous (LC-SP); d- fixed (F-SP) sporotrichosis. LCL-ATL and SCL-ATL had a significantly higher percentage of CD8, FasL and NOS2 than sporotrichosis. In contrast, LC-SP had a substantially higher percentage of CD4, BCl2 and neutrophils than ATL lesions. These results indicated some differences in the profile of the in situ immune response suggesting that SIS is a complex, adaptable system capable of different responses to intracellular or extracellular pathogens. However, regardless of the etiological agents, the inflammatory reaction and clinical manifestations can be similar. SCL-ATL and LC-SP presented similarities in both clinical presentation and in situ inflammatory profile (CD3, CD22, neutrophils, macrophages). The clinical presentation of ATL and sporotrichosis could be explained by a combination of factors both of the host SIS and the etiological agent. The unbalanced host parasite relationship could result in atypical manifestations of skin disease.

  1. Use of Three-Level Power Converters in Wind-Driven Permanent-Magnet Synchronous Generators with Unbalanced Loads

    Directory of Open Access Journals (Sweden)

    Ming-Hung Chen

    2015-06-01

    Full Text Available This paper describes the design and implementation of three-level power converters for wind-driven permanent-magnet synchronous generators with unbalanced loads. To increase voltage stress and reduce current harmonics in the electrical power generated by a wind generator, a three-phase, three-level rectifier is used. Because a synchronous rotating frame is used on the AC-input side, the use of a neutral-point-clamped controller is proposed to increase the power factor to unity and reduce current harmonics. Furthermore, a novel six-leg inverter is proposed for transferring energy from the DC voltage to a three-phase, four-wire AC source with a constant voltage and a constant frequency. The power converters also contain output transformers and filters for power buffering and filtering, respectively. All three output phase voltages are fed back to control the inverter output during load variations. A digital signal processor is used as the core control device for implementing a 1.5 kV, 75 kW drive system. Experimental data show that the power factor is successfully increased to unity and the total current harmonic distortion is 3.2% on the AC-input side. The entire system can attain an efficiency of 91%, and the voltage error between the upper and lower capacitors is approximately zero. Experimental results that confirm the high performance of the proposed system are presented.

  2. Association of Affect with Vertical Position in L1 but not in L2 in Unbalanced Bilinguals

    Directory of Open Access Journals (Sweden)

    Degao eLi

    2015-05-01

    Full Text Available After judging the valence of the positive (e.g., happy and the negative words (e.g., sad, the participants’ response to the letter (q or p was faster and slower, respectively, when the letter appeared at the upper end than at the lower end of the screen in Meier & Robinson’ (2004 second experiment. To compare this metaphorical association of affect with vertical position in Chinese-English bilinguals’ first language (L1 and second language (L2 (language, we conducted four experiments in an affective priming task. The targets were one set of positive or negative words (valence, which were shown vertically above or below the centre of the screen (position. The primes, presented at the centre of the screen, were affective words that were semantically related to the targets, affective words that were not semantically related to the targets, affective icon-pictures, and neutral strings in experiment 1, 2, 3, and 4, respectively. In judging the targets’ valence, the participants showed different patterns of interactions between language, valence, and position in reaction times across the experiments. We concluded that metaphorical association between affect and vertical position works in L1 but not in L2 for unbalanced bilinguals.

  3. Optical characterization of hydrogen-free CeO2 doped DLC films deposited by unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Zhang Zhenyu; Zhou Hongxiu; Guo Dongming; Gao Hang; Kang Renke

    2008-01-01

    A novel kind of hydrogen-free CeO 2 doped diamond-like carbon (DLC) films with thickness of 180-200 nm were deposited on silicon by unbalanced magnetron sputtering. Reduced reflectance and increased lifetime are expected with respect to pure DLC films, making these coatings good candidates as optical protective coatings for IR windows and solar cells. X-ray photoelectron spectroscopy confirms that CeO 2 is formed within the DLC films. Auger electron spectroscopy exhibits that the C, O, and Ce elements distribute uniformly across the film thickness, and C element diffuses into the Si substrate at the interface between the substrate and film. AFM shows that nanoparticles with diameter of around 50 nm are formed on the surface of deposited films, whose surface roughness is in the range of 1.3-2.3 nm. Raman spectra show the CeO 2 doped DLC films are amorphous DLC films, and both the G frequency and relative intensity ratio I D /I G are higher than those of pure DLC films. The photoluminescence of CeO 2 doped DLC films is obviously more intense than that of a pure DLC film, which indicates a promising potential as optical protective films for solar cells and IR window

  4. Fault ride-through capability of wind turbine connected to the grid in case of unbalanced voltages

    Directory of Open Access Journals (Sweden)

    Ivanović Zoran R.

    2016-01-01

    Full Text Available This paper deals with control of wind turbine connected to the grid through the back-to-back converter in case of unbalanced grid voltages. The motivation for this research has been found in recent transmission and distribution grid code, which demand modern wind turbines to stay connected to the grid and supply the highest possible apparent power during the grid disturbances. In order to comply with these requirements we proposed improved dual vector current controller to deal with the unbalance imposed by the electrical grid. Controller provides injection of active and reactive power to the grid, even if the voltages are lower than the nominal one. The results are validated using low power prototype and contemporary hardware-in-the-loop emulation platform. In both cases the controller is based on TMS320F2812 DSP. [Projekat Ministarstva nauke Republike Srbije, br. III 042004 and by the Provincial Secretariat for Science and Technological Development of AP Vojvodina under contract No. 114-451-3508/2013-04

  5. Distributed Technologies in a Data Pool

    Science.gov (United States)

    Keiser, K.; Conover, H.; Graves, S.; He, Y.; Regner, K.; Smith, M.

    2004-12-01

    A Data Pool is an on-line repository providing interactive and programmatic access to data products through a variety of services. The University of Alabama in Huntsville has developed and deployed such a Data Pool in conjunction with the DISCOVER project, a collaboration with NASA and Remote Sensing Systems. DISCOVER provides long-term ocean and climate data from a variety of passive microwave satellite instruments, including such products as sea-surface temperature and wind, air temperature, atmospheric water vapor, cloud water and rain rate. The Data Pool provides multiple methods to access and visualize these products, including conventional HTTP and FTP access, as well as data services that provide for enhanced usability and interoperability, such as GridFTP, OPeNDAP, OpenGIS-compliant web mapping and coverage services, and custom subsetting and packaging services. This paper will focus on the distributed service technologies used in the Data Pool, which spans heterogeneous machines at multiple locations. For example, in order to provide seamless access to data at multiple sites, the Data Pool provides catalog services for all data products at the various data server locations. Under development is an automated metadata generation tool that crawls the online data repositories regularly to dynamically update the Data Pool catalog with information about newly generated data files. For efficient handling of data orders across distributed repositories, the Data Pool also implements distributed data processing services on the file servers where the data resides. Ontologies are planned to support automated service chaining for custom user requests. The UAH Data Pool is based on a configurable technology framework that integrates distributed data services with a web interface and a set of centralized database services for catalogs and order tracking. While this instantiation of the Data Pool was implemented to meet the needs of the DISCOVER project, the framework was

  6. A Pool of Distant Galaxies

    Science.gov (United States)

    2008-11-01

    Anyone who has wondered what it might be like to dive into a pool of millions of distant galaxies of different shapes and colours, will enjoy the latest image released by ESO. Obtained in part with the Very Large Telescope, the image is the deepest ground-based U-band image of the Universe ever obtained. It contains more than 27 million pixels and is the result of 55 hours of observations with the VIMOS instrument. A Sea of Galaxies ESO PR Photo 39/08 A Pool of Distant Galaxies This uniquely beautiful patchwork image, with its myriad of brightly coloured galaxies, shows the Chandra Deep Field South (CDF-S), arguably the most observed and best studied region in the entire sky. The CDF-S is one of the two regions selected as part of the Great Observatories Origins Deep Survey (GOODS), an effort of the worldwide astronomical community that unites the deepest observations from ground- and space-based facilities at all wavelengths from X-ray to radio. Its primary purpose is to provide astronomers with the most sensitive census of the distant Universe to assist in their study of the formation and evolution of galaxies. The new image released by ESO combines data obtained with the VIMOS instrument in the U- and R-bands, as well as data obtained in the B-band with the Wide-Field Imager (WFI) attached to the 2.2 m MPG/ESO telescope at La Silla, in the framework of the GABODS survey. The newly released U-band image - the result of 40 hours of staring at the same region of the sky and just made ready by the GOODS team - is the deepest image ever taken from the ground in this wavelength domain. At these depths, the sky is almost completely covered by galaxies, each one, like our own galaxy, the Milky Way, home of hundreds of billions of stars. Galaxies were detected that are a billion times fainter than the unaided eye can see and over a range of colours not directly observable by the eye. This deep image has been essential to the discovery of a large number of new galaxies

  7. A case of an atypically large proximal 15q deletion as cause for Prader-Willi syndrome arising from a de novo unbalanced translocation.

    Science.gov (United States)

    Hickey, Scott E; Thrush, Devon Lamb; Walters-Sen, Lauren; Reshmi, Shalini C; Astbury, Caroline; Gastier-Foster, Julie M; Atkin, Joan

    2013-09-01

    We describe an 11 month old female with Prader-Willi syndrome (PWS) resulting from an atypically large deletion of proximal 15q due to a de novo 3;15 unbalanced translocation. The 10.6 Mb deletion extends from the chromosome 15 short arm and is not situated in a region previously reported as a common distal breakpoint for unbalanced translocations. There was no deletion of the reciprocal chromosome 3q subtelomeric region detected by either chromosomal microarray or FISH. The patient has hypotonia, failure to thrive, and typical dysmorphic facial features for PWS. The patient also has profound global developmental delay consistent with an expanded, more severe, phenotype. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Modal analysis of pool door in water tank

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kang Soo; Jeong, Kyeong Hoon; Park, Chan Gook; Koo, In Soo [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    A pool door is installed at the chase of the pool gate by means of an overhead crane in the building of a research reactor. The principal function of the pool door, which is located between the reactor pool and service pool, is to separate the reactor pool from the service pool for the maintenance and/or the removal of the equipment either in the reactor pool or service pool. The pool door consists of stainless steel plates supported by structural steel frames and sealing components. The pool door is equipped with double inflatable gaskets. The configuration of the pool door is shown in Figure 1. The FEM analysis and theoretical calculation by the formula were performed to evaluate the natural frequency for the pool door in the water. The results from the two methods were compared.

  9. The Role of Nuclear Insurance Pools

    International Nuclear Information System (INIS)

    Reitsma, S. M. S.

    2006-01-01

    Since fifty years insurers respond to the need of both governments and the electricity industry to provide financial protection to cover the perils presented by the use of nuclear energy for peaceful purposes. This paper aims at explaining what difficulties had to be solved in order to enable insurers to provide such protection, that as a solution to these difficulties Nuclear Insurance Pools were formed, how such pools operate and what security they provide. Thereby not only a number of universal principles underlying nuclear pool insurance will be explained, but also some differences in the characteristics of such insurance per group of countries. (author)

  10. Laser surveillance systems for fuel storage pools

    International Nuclear Information System (INIS)

    Boeck, H.

    1985-06-01

    A Laser Surveillance System (LASSY) as a new safeguards device has been developed under the IAEA research contract No. 3458/RB at the Atominstitut Wien using earlier results by S. Fiarman. This system is designed to act as a sheet of light covering spent fuel assemblies in spent fuel storage pools. When movement of assemblies takes place, LASSY detects and locates the position of the movement in the pool and when interrogated, presents a list of pool positions and times of movement to the safeguards inspector. A complete prototype system was developed and built. Full scale tests showed the principal working capabilities of a LASSY underwater

  11. Control of Grid Integrated Voltage Source Converters under Unbalanced Conditions: Development of an On-line Frequency-adaptive Virtual Flux-based Approach

    OpenAIRE

    Suul, Jon Are

    2012-01-01

    Three-Phase Voltage Source Converters (VSCs) are finding widespread applications in grid integrated power conversion systems. The control systems of such VSCs are in an increasing number of these applications required to operate during voltage disturbances and unbalanced conditions. Control systems designed for grid side voltagesensor- less operation are at the same time becoming attractive due to the continuous drive for cost reduction and increased reliability of VSCs, but are not commonly ...

  12. Recurrence, submicroscopic complexity, and potential clinical relevance of copy gains detected by array CGH that are shown to be unbalanced insertions by FISH.

    Science.gov (United States)

    Neill, Nicholas J; Ballif, Blake C; Lamb, Allen N; Parikh, Sumit; Ravnan, J Britt; Schultz, Roger A; Torchia, Beth S; Rosenfeld, Jill A; Shaffer, Lisa G

    2011-04-01

    Insertions occur when a segment of one chromosome is translocated and inserted into a new region of the same chromosome or a non-homologous chromosome. We report 71 cases with unbalanced insertions identified using array CGH and FISH in 4909 cases referred to our laboratory for array CGH and found to have copy-number abnormalities. Although the majority of insertions were non-recurrent, several recurrent unbalanced insertions were detected, including three der(Y)ins(Y;18)(q?11.2;p11.32p11.32)pat inherited from parents carrying an unbalanced insertion. The clinical significance of these recurrent rearrangements is unclear, although the small size, limited gene content, and inheritance pattern of each suggests that the phenotypic consequences may be benign. Cryptic, submicroscopic duplications were observed at or near the insertion sites in two patients, further confounding the clinical interpretation of these insertions. Using FISH, linear amplification, and array CGH, we identified a 126-kb duplicated region from 19p13.3 inserted into MECP2 at Xq28 in a patient with symptoms of Rett syndrome. Our results demonstrate that although the interpretation of most non-recurrent insertions is unclear without high-resolution insertion site characterization, the potential for an otherwise benign duplication to result in a clinically relevant outcome through the disruption of a gene necessitates the use of FISH to determine whether copy-number gains detected by array CGH represent tandem duplications or unbalanced insertions. Further follow-up testing using techniques such as linear amplification or sequencing should be used to determine gene involvement at the insertion site after FISH has identified the presence of an insertion.

  13. 10 CFR 36.63 - Pool water purity.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Pool water purity. 36.63 Section 36.63 Energy NUCLEAR... § 36.63 Pool water purity. (a) Pool water purification system must be run sufficiently to maintain the conductivity of the pool water below 20 microsiemens per centimeter under normal circumstances. If pool water...

  14. An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions

    Science.gov (United States)

    Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M.

    2017-01-01

    In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method. PMID:28192436

  15. An improved synchronous reference frame current control strategy for a photovoltaic grid-connected inverter under unbalanced and nonlinear load conditions.

    Science.gov (United States)

    Naderipour, Amirreza; Asuhaimi Mohd Zin, Abdullah; Bin Habibuddin, Mohd Hafiz; Miveh, Mohammad Reza; Guerrero, Josep M

    2017-01-01

    In recent years, renewable energy sources have been considered the most encouraging resources for grid and off-grid power generation. This paper presents an improved current control strategy for a three-phase photovoltaic grid-connected inverter (GCI) under unbalanced and nonlinear load conditions. It is challenging to suppress the harmonic content in the output current below a pre-set value in the GCI. It is also difficult to compensate for unbalanced loads even when the grid is under disruption due to total harmonic distortion (THD) and unbalanced loads. The primary advantage and objective of this method is to effectively compensate for the harmonic current content of the grid current and microgrid without the use of any compensation devices, such as active and passive filters. This method leads to a very low THD in both the GCI currents and the current exchanged with the grid. The control approach is designed to control the active and reactive power and harmonic current compensation, and it also corrects the system unbalance. The proposed control method features the synchronous reference frame (SRF) method. Simulation results are presented to demonstrate the effective performance of the proposed method.

  16. The Nuclear Insurance Pools: Operations and Covers

    International Nuclear Information System (INIS)

    Tetley, M.

    2008-01-01

    Nuclear insurance pools have provided insurance for the nuclear industry for over fifty years and it is fair to say that the development of civil nuclear power would not have been possible without the support of the commercial insurance market. The unknown risks presented by the nascent nuclear power industry in the 1950s required a leap of faith by insurers who developed specialist pooled insurance capacity to ensure adequate capacity to back up the operators' compensation obligations. Since then, nuclear insurance pools have evolved to become comprehensive suppliers of most types of insurance for nuclear plant globally. This paper will outline the structure, development, products and current operations of nuclear insurance pools.(author)

  17. Ingestion of swimming pool water by recreational

    Data.gov (United States)

    U.S. Environmental Protection Agency — Swimming pool water ingestion data. This dataset is associated with the following publication: Dufour, A., L. Wymer, M. Magnuson, T. Behymer, and R. Cantu. Ingestion...

  18. Nuclear Insurance Pools: Worldwide Practice and Development

    International Nuclear Information System (INIS)

    Reitsma, S. M. S.

    1998-01-01

    The development of nuclear installations to produce electricity led to the establishment of Nuclear Insurance Pools and the introduction of international Conventions on Third Party Liability. Nuclear Pools offer both Third Party Liability insurance, reflecting the Conventions' principles, and other insurance products. They are market-wide, providing a facility for participation by insurers who could not otherwise write the insurance for the particularly sensitive nuclear risk. All acceptances are for the net retention of each Member without recourse to individual reinsurance protection. Common account reinsurance is arranged with other Nuclear Pools all over the world. Thus, a transparency is created, which ensures the highest degree of reinsurance security and imposes a known finite limit to each participating insurer's commitment. Therefore, Pool-members are prepared to make a greater commitment to nuclear risks than would be case where they felt uncertain as regards their total exposure following a significant loss. (author)

  19. AE/VCE Unconfirmed Vernal Pools

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

  20. AE/VCE Confirmed Vernal Pools

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is derived from a project by the Vermont Center for Ecostudies(VCE) and Arrowwood Environmental(AE) to map vernal pools throughout the state of Vermont....

  1. Investigations in Marine Chemistry: Tide Pool Ecology.

    Science.gov (United States)

    Schlenker, Richard M.

    Students investigated the salinity of tide pools at different levels in the intertidal zone. Data are analyzed collectively. Students graphed and discussed data. Included are suggestions for evaluation and further study. (Author)

  2. 7 CFR 1126.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... excluded from the supply plant's shipments in computing the plant's shipping percentage. (d) A plant... part, or the plant has automatic pooling status under the other Federal order; and (7) That portion of...

  3. 7 CFR 1001.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... excluded from the supply plant's shipments in computing the percentages in paragraphs (c)(1) and (2) of... plant has automatic pooling status under the other Federal order. [64 FR 47954, Sept. 1, 1999, as...

  4. 7 CFR 1007.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ...-upon use other than Class I shall be excluded from the supply plant's shipments in computing the plant... under the order in this part, or such plant has automatic pooling status under such other order. (h) Any...

  5. Microbial quality of a marine tidal pool

    CSIR Research Space (South Africa)

    Genthe, Bettina

    1995-01-01

    Full Text Available In this study the source of microbial pollution to a tidal pool was investigated. Both adjacent seawater which could contribute to possible faecal pollution and potential direct bather pollution were studied. The microbial quality of the marine...

  6. Robotic cleaning of a spent fuel pool

    International Nuclear Information System (INIS)

    Roman, H.T.; Marian, F.A.; Silverman, E.B.; Barkley, V.P.

    1987-01-01

    Spent fuel pools at nuclear power plants are not cleaned routinely, other than by purifying the water that they contain. Yet, debris can collect on the bottom of a pool and should be removed prior to fuel transfer. At Public Service Electric and Gas Company's Hope Creek Nuclear Power Plant, a submersible mobile robot - ARD Corporation's SCAVENGER - was used to clean the bottom of the spent fuel pool prior to initial fuel loading. The robotic device was operated remotely (as opposed to autonomously) with a simple forward/reverse control, and it cleaned 70-80% of the pool bottom. This paper reports that a simple cost-benefit analysis shows that the robotic device would be less expensive, on a per mission basis, than other cleaning alternatives, especially if it were used for other similar cleaning operations throughout the plant

  7. Pooling strategies for St Petersburg gamblers

    OpenAIRE

    Csörgö, Sandor; Simons, Gordon

    2006-01-01

    Peter offers to play exactly one St Petersburg game with each of [math] players, Paul [math] , [math] , Paul [math] , whose conceivable pooling strategies are described by all possible probability distributions [math] . Comparing infinite expectations, we characterize among all [math] those admissible strategies for which the pooled winnings, each distributed as [math] , yield a finite added value for each and every one of Paul [math] , [math] , Paul [math] in comparison with their individual...

  8. Welding pool measurement using thermal array sensor

    Science.gov (United States)

    Cho, Chia-Hung; Hsieh, Yi-Chen; Chen, Hsin-Yi

    2015-08-01

    Selective laser melting (SLM) is an additive manufacturing (AM) technology that uses a high-power laser beam to melt metal powder in chamber of inert gas. The process starts by slicing the 3D CAD data as a digital information source into layers to create a 2D image of each layer. Melting pool was formed by using laser irradiation on metal powders which then solidified to consolidated structure. In a selective laser melting process, the variation of melt pool affects the yield of a printed three-dimensional product. For three dimensional parts, the border conditions of the conductive heat transport have a very large influence on the melt pool dimensions. Therefore, melting pool is an important behavior that affects the final quality of the 3D object. To meet the temperature and geometry of the melting pool for monitoring in additive manufacturing technology. In this paper, we proposed the temperature sensing system which is composed of infrared photodiode, high speed camera, band-pass filter, dichroic beam splitter and focus lens. Since the infrared photodiode and high speed camera look at the process through the 2D galvanometer scanner and f-theta lens, the temperature sensing system can be used to observe the melting pool at any time, regardless of the movement of the laser spot. In order to obtain a wide temperature detecting range, 500 °C to 2500 °C, the radiation from the melting pool to be measured is filtered into a plurality of radiation portions, and since the intensity ratio distribution of the radiation portions is calculated by using black-body radiation. The experimental result shows that the system is suitable for melting pool to measure temperature.

  9. Numerical modelling of methanol liquid pool fires

    Science.gov (United States)

    Prasad, Kuldeep; Li, Chiping; Kailasanath, K.; Ndubizu, Chuka; Ananth, Ramagopal; Tatem, P. A.

    1999-12-01

    The focus of this paper is on numerical modelling of methanol liquid pool fires. A mathematical model is first developed to describe the evaporation and burning of a two-dimensional or axisymmetric pool containing pure liquid methanol. Then, the complete set of unsteady, compressible Navier-Stokes equations for reactive flows are solved in the gas phase to describe the convection of the fuel gases away from the pool surface, diffusion of the gases into the surrounding air and the oxidation of the fuel into product species. Heat transfer into the liquid pool and the metal container through conduction, convection and radiation are modelled by solving a modified form of the energy equation. Clausius-Clapeyron relationships are invoked to model the evaporation rate of a two-dimensional pool of pure liquid methanol. The governing equations along with appropriate boundary and interface conditions are solved using the flux-corrected transport algorithm. Numerical results exhibit a flame structure that compares well with experimental observations. Temperature profiles and burning rates were found to compare favourably with experimental data from single- and three-compartment laboratory burners. The model predicts a puffing frequency of approximately 12 Hz for a 1 cm diameter methanol pool in the absence of any air co-flow. It is also observed that increasing the air co-flow velocity helps in stabilizing the diffusion flame, by pushing the vortical structures away from the flame region.

  10. Recent advances in probabilistic species pool delineations

    Directory of Open Access Journals (Sweden)

    Dirk Nikolaus Karger

    2016-07-01

    Full Text Available A species pool is the set of species that could potentially colonize and establish within a community. It has been a commonly used concept in biogeography since the early days of MacArthur and Wilson’s work on Island Biogeography. Despite their simple and appealing definition, an operational application of species pools is bundled with a multitude of problems, which have often resulted in arbitrary decisions and workarounds when defining species pools. Two recently published papers address the operational problems of species pool delineations, and show ways of delineating them in a probabilistic fashion. In both papers, species pools were delineated using a process-based, mechanistical approach, which opens the door for a multitude of new applications in biogeography. Such applications include detecting the hidden signature of biotic interactions, disentangling the geographical structure of community assembly processes, and incorporating a temporal extent into species pools. Although similar in their conclusions, both ‘probabilistic approaches’ differ in their implementation and definitions. Here I give a brief overview of the differences and similarities of both approaches, and identify the challenges and advantages in their application.

  11. Regulation of unbalanced electromagnetic moment in mutual loading systems of electric machines of traction rolling stock and multiple unit of mainline and industrial transport

    Directory of Open Access Journals (Sweden)

    A. M. Afanasov

    2014-12-01

    Full Text Available Purpose. The research data are aimed to identify the regulatory principles of unbalanced electromagnetic moment of mutually loaded electric machines of traction rolling stock and multiple unit of main and industrial transport. The purpose of this study is energy efficiency increase of the testing of traction electric machines of direct and pulse current using the improvement methods of their mutual loading, including the principles of automatic regulation of mutual loading system. Methodology. The general theoretical provisions and principles of system approach to the theoretical electric engineering, the theory of electric machines and theoretical mechanics are the methodological basis of this research. The known methods of analysis of electromagnetic and electromechanical processes in electrical machines of direct and pulse current are used in the study. Methods analysis of loading modes regulation of traction electric machines was conducted using the generalized scheme of mutual loading. It is universal for all known methods to cover the losses of idling using the electric power. Findings. The general management principles of mutual loading modes of the traction electric machines of direct and pulse current by regulating their unbalanced electric magnetic moment were developed. Regulatory options of unbalanced electromagnetic moment are examined by changing the difference of the magnetic fluxes of mutually loaded electric machines, the current difference of electric machines anchors, the difference of the angular velocities of electric machines shafts. Originality. It was obtained the scientific basis development to improve the energy efficiency test methods of traction electric machines of direct and pulse current. The management principles of mutual loading modes of traction electric machines were formulated. For the first time it is introduced the concept and developed the principles of regulation of unbalanced electromagnetic moment in

  12. Thymidine kinase 1 deficient cells show increased survival rate after UV-induced DNA damage

    DEFF Research Database (Denmark)

    Skovgaard, T; Rasmussen, Lene Juel; Munch-Petersen, Birgitte

    2010-01-01

    Balanced deoxynucleotide pools are known to be important for correct DNA repair, and deficiency for some of the central enzymes in deoxynucleotide metabolism can cause imbalanced pools, which in turn can lead to mutagenesis and cell death. Here we show that cells deficient for the thymidine salva...

  13. Surface free energy of non-stick coatings deposited using closed field unbalanced magnetron sputter ion plating

    International Nuclear Information System (INIS)

    Sun, C.-C.; Lee, S.-C.; Dai, S.-B.; Tien, S.-L.; Chang, C.-C.; Fu, Y.-S.

    2007-01-01

    Semiconductor IC packaging molding dies require wear resistance, corrosion resistance and non-sticking (with a low surface free energy). The molding releasing capability and performance are directly associated with the surface free energy between the coating and product material. The serious sticking problem reduces productivity and reliability. Depositing TiN, TiMoS, ZrN, CrC, CrN, NiCr, NiCrN, CrTiAlN and CrNiTiAlN coatings using closed field unbalanced magnetron sputter ion plating, and characterizing their surface free energy are the main object in developing a non-stick coating system for semiconductor IC molding tools. The contact angle of water, diiodomethane and ethylene glycol on the coated surfaces were measured at temperature in 20 deg. C using a Dataphysics OCA-20 contact angle analyzer. The surface free energy of the coatings and their components (dispersion and polar) were calculated using the Owens-Wendt geometric mean approach. The surface roughness was investigated by atomic force microscopy (AFM). The adhesion force of these coatings was measured using direct tensile pull-off test apparatus. The experimental results showed that NiCrN, CrN and NiCrTiAlN coatings outperformed TiN, ZrN, NiCr, CiTiAlN, CrC and TiMoS coatings in terms of non-sticking, and thus have the potential as working layers for injection molding industrial equipment, especially in semiconductor IC packaging molding applications

  14. Self-formed waterfall plunge pools in homogeneous rock

    Science.gov (United States)

    Scheingross, Joel S.; Lo, Daniel Y.; Lamb, Michael P.

    2017-01-01

    Waterfalls are ubiquitous, and their upstream propagation can set the pace of landscape evolution, yet no experimental studies have examined waterfall plunge pool erosion in homogeneous rock. We performed laboratory experiments, using synthetic foam as a bedrock simulant, to produce self-formed waterfall plunge pools via particle impact abrasion. Plunge pool vertical incision exceeded lateral erosion by approximately tenfold until pools deepened to the point that the supplied sediment could not be evacuated and deposition armored the pool bedrock floor. Lateral erosion of plunge pool sidewalls continued after sediment deposition, but primarily at the downstream pool wall, which might lead to undermining of the plunge pool lip, sediment evacuation, and continued vertical pool floor incision in natural streams. Undercutting of the upstream pool wall was absent, and our results suggest that vertical drilling of successive plunge pools is a more efficient waterfall retreat mechanism than the classic model of headwall undercutting and collapse in homogeneous rock.

  15. Structure of pool in reactor building

    International Nuclear Information System (INIS)

    Yokoyama, Shigeki.

    1997-01-01

    Shielding walls made of iron-reinforced concrete having a metal liner including two body walls rigidly combined to the upper surface of a reactor container are disposed at least to one of an equipment pool or spent fuel storage pool in a reactor building. A rack for temporarily placing an upper lattice plate is detachably attached at least above one of a steam dryer or a gas/liquid separator temporarily placed in the temporary pool, and the height from the bottom portion to the upper end of the shielding wall is determined based on the height of an upper lattice plate temporary placed on the rack and the water depth required for shielding radiation from the upper lattice plate. An operator's exposure on the operation floor can be reduced by the shielding wall, and radiation dose from the spent fuels is reduced. The increase of the height of a pool guarder enhances bending resistance as a ceiling. In addition, the total height of them is made identical with the depth of the spent fuel storage pool thereby enabling to increase storage area for spent fuels. (N.H.)

  16. Cooling device for reactor suppression pool

    International Nuclear Information System (INIS)

    Togasaki, Susumu; Kato, Kiyoshi.

    1994-01-01

    In a cooling device of a reactor suppression pool, when a temperature of pool water is abnormally increased and a heat absorbing portion is heated by, for example, occurrence of an accident, coolants are sent to the outside of the reactor container to actuates a thermally operating portion by the heat energy of coolants and drive heat exchanging fluids of a secondary cooling system. If the heat exchanging fluids are sent to a cooling portion, the coolants are cooled and returned to the heat absorbing portion of the suppression pool water. If the heat absorbing portion is heat pipes, the coolants are evaporated by heat absorbed from the suppression pool water, steams are sent to the thermally operating portion, then coolants are liquefied and caused to return to the heat absorbing portion. If the thermal operation portion is a gas turbine, the gas turbine is operated by the coolants, and it is converted to a rotational force to drive heat exchanging fluids by pumps. By constituting the cooling portion with a condensator, the coolants are condensed and liquefied and returned to the heat absorbing portion of the suppression pool water. (N.H.)

  17. Condensation in a two-phase pool

    International Nuclear Information System (INIS)

    Duffey, R.B.; Hughes, E.D.

    1991-01-01

    We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine some limits in ideal cases

  18. 13 CFR 120.1706 - Pool Originator's retained interest in Pool.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pool Originator's retained interest in Pool. 120.1706 Section 120.1706 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan...

  19. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    spreading of pathogens between swimmers because of its residual disinfection effect. In addition to potential contamination of pathogenic microorganisms, swimming pool water is polluted by organic matter deposited from the bathers such as saliva, urine, sweat, hair and personal care products. Since chlorine...... is a strong oxidant it oxidizes the organic matter in the pool water and forms disinfection byproducts (DBPs). More than 100 different DBPs have been identified. Some of these have been found to be genotoxic and may pose an increased cancer risk for the bathers. The aim of this thesis was to give an overview...... of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

  20. An unbalanced portfolio.

    Science.gov (United States)

    Federsel, Hans-Jurgen

    2009-06-01

    An excellent demonstration of how meaningful and valuable conferences devoted to the topic of project and portfolio management in the pharmaceutical industry can be, was given at an event organized in Barcelona, September 2008. Thus, over this 2-day meeting the delegates were updated on the state of the art in this wide-reaching area from speakers representing an array of companies; from small, relatively new players, via mid-sized, to established large and big pharmas. One common theme that emerged was the importance of assessing the value of drug projects as correctly as possible, especially under the current financial climate and the many challenges facing the industry. Furthermore, experiences from constructing portfolios with the aim to minimize risk and maximize return on investment were shared alongside mathematical approaches to obtain the data required for this purpose and accounts of the pleasures and hardships working in a global context and in partnership constellations. Copyright 2009 Prous Science, S.A.U. or its licensors. All rights reserved.

  1. Simulation of pool scrubbing experiments using BUSCA

    International Nuclear Information System (INIS)

    Dehbi, A.; Guentay, S.

    1994-01-01

    BUSCA-PSI is a computer code which predicts the aerosol scrubbing taking place when gas bubbles containing fission products rise through stagnant pools of water after a postulated severe accident. A Lagrangian formulation is adopted to follow the path of a bubble as it rises toward the surface of the pool. The BUSCA model includes most aerosol removal mechanisms which are thought to be significant, namely: Jet Impaction at tile orifice, Convection/Diffusiophoresis during steam condensation, Thermophoresis, Sedimentation, Centrifugal Impaction during bubble rise, and Brownian Diffusion. The hydraulic modelling offers a variety of options for the initial globule volume, the stable bubble size, tile bubble rise velocity, and the bubble shape. The heat and mass transfer part of tile model uses correlations found in the relevant literature. BUSCA simulations were performed to determine the decontamination factor (DF) dependence on key aerosol and thermal hydraulic parameters. The decontamination factor increases with height, pool temperature subcooling, and steam content. The decontamination factor exhibits a parabolic dependence on the particle radius. At low particle sizes, the DF is high due to Brownian Diffusion which is the dominant removal mechanism. The DF hits a minimum and then increases with particle size as Centrifugal Impaction and Sedimentation become important. In separate calculations, BUSCA was used to the simulate the aerosol scrubbing experiments performed by EPRI. For cold pool tests, the predicted scrubbing efficiencies were in a good, conservative agreement with the data for both Tin and CsI, and the discrepancies were within the reported measurement errors. For hot pool tests, the code systematically underpredicted the scrubbing DF's; this is potentially due to condensation in the gas space above the pool, a situation not currently modelled by BUSCA. The code was also tested against data produced by the Tepco-Toshiba-Hitachi experiments. The

  2. Zooplankton at deep Red Sea brine pools

    KAUST Repository

    Kaartvedt, Stein

    2016-03-02

    The deep-sea anoxic brines of the Red Sea comprise unique, complex and extreme habitats. These environments are too harsh for metazoans, while the brine–seawater interface harbors dense microbial populations. We investigated the adjacent pelagic fauna at two brine pools using net tows, video records from a remotely operated vehicle and submerged echosounders. Waters just above the brine pool of Atlantis II Deep (2000 m depth) appeared depleted of macrofauna. In contrast, the fauna appeared to be enriched at the Kebrit Deep brine–seawater interface (1466 m).

  3. One component, volume heated, boiling pool thermohydraulics

    International Nuclear Information System (INIS)

    Bede, M.; Perret, C.; Pretrel, H.; Seiler, J.M.

    1993-01-01

    Prior work on boiling pools provided heat exchange correlations valid for bubbly flow with laminar or turbulent boundary layers. New experiments performed with water (SEBULON) and UO 2 (SCARABEE BF2) in a churn-turbulent flow configuration show unexpected heat flux distributions for which the maximum heat flux may be situated well below the pool surface. The origin of this behaviour is attributed to condensation effects, very unstable boundary layer flow and surface oscillation. A calculation model is discussed which permits to approach the experimental heat flux distribution with reasonable accuracy. (authors). 7 figs., 2 appendix., 14 refs

  4. Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

    International Nuclear Information System (INIS)

    Sathiah, Pratap; Roelofs, Ferry

    2014-01-01

    Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor

  5. Numerical modeling of sodium fire – Part II: Pool combustion and combined spray and pool combustion

    Energy Technology Data Exchange (ETDEWEB)

    Sathiah, Pratap, E-mail: pratap.sathiah78@gmail.com [Shell Global Solutions Ltd., Brabazon House, Concord Business Park, Threapwood Road, Manchester M220RR (United Kingdom); Roelofs, Ferry, E-mail: roelofs@nrg.eu [Nuclear Research and Consultancy Group (NRG), Westerduinweg 3, 1755ZG Petten (Netherlands)

    2014-10-15

    Highlights: • A CFD based method is proposed for the simulation of sodium pool combustion. • A sodium evaporation based model is proposed to model sodium pool evaporation. • The proposed method is validated against sodium pool experiments of Newman and Payne. • The results obtained using the proposed method are in good agreement with the experiments. - Abstract: The risk of sodium-air reaction has received considerable attention after the sodium-fire accident in Monju reactor. The fires resulting from the sodium-air reaction can be detrimental to the safety of a sodium fast reactor. Therefore, predicting the consequences of a sodium fire is important from a safety point of view. A computational method based on CFD is proposed here to simulate sodium pool fire and understand its characteristics. The method solves the Favre-averaged Navier-Stokes equation and uses a non-premixed mixture fraction based combustion model. The mass transfer of sodium vapor from the pool surface to the flame is obtained using a sodium evaporation model. The proposed method is then validated against well-known sodium pool experiments of Newman and Payne. The flame temperature and location predicted by the model are in good agreement with experiments. Furthermore, the trends of the mean burning rate with initial pool temperature and oxygen concentration are captured well. Additionally, parametric studies have been performed to understand the effects of pool diameter and initial air temperature on the mean burning rate. Furthermore, the sodium spray and sodium pool combustion models are combined to simulate simultaneous spray and pool combustion. Simulations were performed to demonstrate that the combined code could be applied to simulate this. Once sufficiently validated, the present code can be used for safety evaluation of a sodium fast reactor.

  6. 13 CFR 120.1705 - Pool formation requirements.

    Science.gov (United States)

    2010-01-01

    ... requirements. SBA may adjust the Pool characteristics periodically based on program experience and market... a Pool involving a Pool Loan it does not own, it must purchase the Loan Interest it proposes to pool... purchase the Loan Interest and take it into inventory or settle the purchase of the Loan Interest through...

  7. Delineating probabilistic species pools in ecology and biogeography

    OpenAIRE

    Karger, Dirk Nikolaus; Cord, Anna F; Kessler, Michael; Kreft, Holger; Kühn, Ingolf; Pompe, Sven; Sandel, Brody; Sarmento Cabral, Juliano; Smith, Adam B; Svenning, Jens-Christian; Tuomisto, Hanna; Weigelt, Patrick; Wesche, Karsten

    2016-01-01

    Aim To provide a mechanistic and probabilistic framework for defining the species pool based on species-specific probabilities of dispersal, environmental suitability and biotic interactions within a specific temporal extent, and to show how probabilistic species pools can help disentangle the geographical structure of different community assembly processes. Innovation Probabilistic species pools provide an improved species pool definition based on probabilities in conjuncti...

  8. A strategy for optimizing item-pool management

    NARCIS (Netherlands)

    Ariel, A.; van der Linden, Willem J.; Veldkamp, Bernard P.

    2006-01-01

    Item-pool management requires a balancing act between the input of new items into the pool and the output of tests assembled from it. A strategy for optimizing item-pool management is presented that is based on the idea of a periodic update of an optimal blueprint for the item pool to tune item

  9. Composition, structure and properties of SiN x films fabricated by pulsed reactive closed-field unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Yao, Zh.Q.; Yang, P.; Huang, N.; Sun, H.; Wan, G.J.; Leng, Y.X.; Chen, J.Y.

    2005-01-01

    Silicon nitride (SiN x ) thin films are of special interest in both scientific research and industrial applications due to their remarkable properties such as high thermal stability, chemical inertness, high hardness and good dielectric properties. In this work, SiN x films were fabricated by pulsed reactive closed-field unbalanced magnetron sputtering of high purity single crystal silicon targets in an Ar-N 2 mixture. The effect of N 2 partial pressure on the film composition, chemical bonding configurations, surface morphology, surface free energy, optical and mechanical properties were investigated. We showed that with increased N 2 partial pressure, the N to Si ratio (N/Si) in the film increased and N atoms are preferentially incorporated in the NSi 3 stoichiometric configuration. It leads the Si-N network a tendency to chemical order. Films deposited at a high N 2 fraction were consistently N-rich. The film surface transformed from a loose granular structure with microporosity to a homogeneous, continuous, smooth and dense structure. A progressive densification of the film microstructure occurs as the N 2 fraction is increased. The reduced surface roughness and the increased N incorporation in the film give rise to the increased contact angle with double-distilled water from 24 o to 49.6 o . To some extent, the SiN x films deposited by pulsed magnetron sputtering are hydrophilic in nature. The as-deposited SiN x films exhibit good optical transparency in the visible region and the optical band gap E opt can be varied from 1.68 eV for a-Si to 3.62 eV for SiN x films, depending on the synthesis parameters. With the increase of the N/Si atomic ratio, wear resistance of the SiN x films was improved, a consequence of increased hardness and elastic modulus. The SiN x films have lower friction coefficient and better wear resistance than 316L stainless steel under dry sliding friction, where the SiN x films experienced only fatigue wear

  10. Corrosion resistance of zirconium oxynitride coatings deposited via DC unbalanced magnetron sputtering and spray pyrolysis-nitriding

    Energy Technology Data Exchange (ETDEWEB)

    Cubillos, G.I., E-mail: gcubillos@unal.edu.co [Department of Chemistry, Group of Materials and Chemical Processes, Universidad Nacional de Colombia, Av. Cra. 30 No 45-03, Bogotá (Colombia); Bethencourt, M., E-mail: manuel.bethencourt@uca.es [Department of Materials Science, Metallurgy Engineering and Inorganic Chemistry, International Campus of Excellence of the Sea - CEI-MAR, University of Cadiz, Avda. República Saharaui s/n, 11510 Puerto Real, Cádiz (Spain); Olaya, J.J., E-mail: jjolayaf@unal.edu.co [Faculty of Engineering, Group of Materials and Chemical Processes, Universidad Nacional de Colombia, Av. Cra. 30 No 45-03, Bogotá (Colombia)

    2015-02-01

    Highlights: • New ZrO{sub x}N{sub y} films were deposited on stainless steel 316L using PSY-N and UBMS. • ZrO{sub x}N{sub y} rhombohedral polycrystalline film grew with PSY-N. • Zr{sub 2}ON{sub 2} crystalline structures, mostly oriented along the (2 2 2) plane, grew with UBMS. • Layers improved corrosion behavior in NaCl media, especially those deposited by UBMS. - Abstract: ZrO{sub x}N{sub y}/ZrO{sub 2} thin films were deposited on stainless steel using two different methods: ultrasonic spray pyrolysis-nitriding (SPY-N) and the DC unbalanced magnetron sputtering technique (UBMS). Using the first method, ZrO{sub 2} was initially deposited and subsequently nitrided in an anhydrous ammonia atmosphere at 1023 K at atmospheric pressure. For UBMS, the film was deposited in an atmosphere of air/argon with a Φair/ΦAr flow ratio of 3.0. Structural analysis was carried out through X-ray diffraction (XRD), and morphological analysis was done through scanning electron microscopy (SEM) and atomic force microscopy (AFM). Chemical analysis was carried out using X-ray photoelectron spectroscopy (XPS). ZrO{sub x}N{sub y} rhombohedral polycrystalline film was produced with spray pyrolysis-nitriding, whereas using the UBMS technique, the oxynitride films grew with cubic Zr{sub 2}ON{sub 2} crystalline structures preferentially oriented along the (2 2 2) plane. Upon chemical analysis of the surface, the coatings exhibited spectral lines of Zr3d, O1s, and N1s, characteristic of zirconium oxynitride/zirconia. SEM analysis showed the homogeneity of the films, and AFM showed morphological differences according to the deposition technique of the coatings. Zirconium oxynitride films enhanced the stainless steel's resistance to corrosion using both techniques. The protective efficacy was evaluated using electrochemical techniques based on linear polarization (LP). The results indicated that the layers provide good resistance to corrosion when exposed to chloride

  11. Composite cavity based fiber optic Fabry–Perot strain sensors demodulated by an unbalanced fiber optic Michelson interferometer with an electrical scanning mirror

    International Nuclear Information System (INIS)

    Zhang, Jianzhong; Yang, Jun; Sun, Weimin; Yuan, Libo; Jin, Wencai; Peng, G D

    2008-01-01

    A composite cavity based fiber optic Fabry–Perot strain sensor system, interrogated by a white light source and demodulated by an unbalanced fiber optic Michelson interferometer with an electrical scanning mirror, is proposed and demonstrated. Comparing with the traditional extrinsic fiber optic Fabry–Perot strain sensor, the potential multiplexing capability and the dynamic measurement range are improved simultaneously. At the same time, the measurement stability of the electrical scanning mirror system is improved by the self-referenced signal of the sensor structure

  12. Public Swimming Pools | Florida Department of Health

    Science.gov (United States)

    Illness Disease Reporting and Surveillance Bureau of Public Health Laboratories Environmental Health Air Air Monitoring Carbon Monoxide Indoor Air Quality Mold Radon Water Aquatic Toxins Beach Water Quality purification, testing, treatment, and disinfection procedures. To ensure that the pool technicians are

  13. 28 CFR 540.64 - Press pools.

    Science.gov (United States)

    2010-07-01

    ... Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT CONTACT WITH PERSONS IN THE COMMUNITY Contact With News Media § 540.64 Press pools. (a) The Warden may establish a... shall notify all news media representatives who have requested interviews or visits that have not been...

  14. Stein's neuronal model with pooled renewal input

    Czech Academy of Sciences Publication Activity Database

    Rajdl, K.; Lánský, Petr

    2015-01-01

    Roč. 109, č. 3 (2015), s. 389-399 ISSN 0340-1200 Institutional support: RVO:67985823 Keywords : Stein’s model * Poisson process * pooled renewal processes * first-passage time Subject RIV: BA - General Mathematics Impact factor: 1.611, year: 2015

  15. Phase analysis in gated blood pool tomography

    International Nuclear Information System (INIS)

    Nakajima, Kenichi; Bunko, Hisashi; Tada, Akira; Taki, Junichi; Nanbu, Ichiro

    1984-01-01

    Phase analysis of gated blood pool study has been applied to detect the site of accessory conduction pathway (ACP) in the Wolff-Parkinson-White (WPW) syndrome; however, there was a limitation to detect the precise location of ACP by phase analysis alone. In this study, we applied phase analysis to gated blood pool tomography using seven pin hole tomography (7PT) and gated emission computed tomography (GECT) in 21 patients with WPW syndrome and 3 normal subjects. In 17 patients, the sites of ACPs were confirmed by epicardial mapping and the result of the surgical division of ACP. In 7PT, the site of ACP grossly agreed to the abnormal initial phase in phase image in 5 out of 6 patients with left cardiac type. In GECT, phase images were generated in short axial, vertical and horizontal long axial sections. In 8 out of 9 patients, the site of ACP was correctly identified by phase images, and in a patient who had two ACPs, initial phase corresponded to one of the two locations. Phase analysis of gated blood pool tomography has advantages for avoiding overlap of blood pools and for estimating three-dimensional propagation of the contraction, and can be a good adjunctive method in patients with WPW syndrome. (author)

  16. Swimming-pool piles; Piles piscines

    Energy Technology Data Exchange (ETDEWEB)

    Trioulaire, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10{sup 13}. This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [French] En France, deux piles piscines, Melusine et Triton, viennent d'entrer en service. La pile piscine est l'outil de recherche ideal pour des flux de neutrons de l'ordre de 10{sup 13}. Ce type de pile peut interesser des maintenant de nombreux centres de recherches mais il faut reduire son prix de revient et rompre avec le conformisme de sa conception. Il y a avantage: - a enterrer la piscine; - a supprimer les canaux experimentaux; - a concentrer le circuit de refrigeration dans la piscine; - a effectuer toutes les manipulations dans l'eau; - a doubler le coeur. (auteur)

  17. Spectrum pooling in MnWave Networks

    DEFF Research Database (Denmark)

    Boccardi, Federico; Shokri-Ghadikolaei, Hossein; Fodor, Gabor

    2016-01-01

    Motivated by the specific characteristics of mmWave technologies, we discuss the possibility of an authorization regime that allows spectrum sharing between multiple operators, also referred to as spectrum pooling. In particular, considering user rate as the performance measure, we assess...

  18. Pooling Objects for Recognizing Scenes without Examples

    NARCIS (Netherlands)

    Kordumova, S.; Mensink, T.; Snoek, C.G.M.

    2016-01-01

    In this paper we aim to recognize scenes in images without using any scene images as training data. Different from attribute based approaches, we do not carefully select the training classes to match the unseen scene classes. Instead, we propose a pooling over ten thousand of off-the-shelf object

  19. The new pooled cohort equations risk calculator

    DEFF Research Database (Denmark)

    Preiss, David; Kristensen, Søren L

    2015-01-01

    disease and any measure of social deprivation. An early criticism of the Pooled Cohort Equations Risk Calculator has been its alleged overestimation of ASCVD risk which, if confirmed in the general population, is likely to result in statin therapy being prescribed to many individuals at lower risk than...

  20. DNA pooling strategies for categorical (ordinal) traits

    Science.gov (United States)

    Despite reduced genotyping costs in recent years, obtaining genotypes for all individuals in a population may still not be feasible when sample size is large. DNA pooling provides a useful alternative to determining genotype effects. Clustering algorithms allow for grouping of individuals (observati...

  1. Pooling ASR data for closely related languages

    CSIR Research Space (South Africa)

    Van Heerden, C

    2010-05-01

    Full Text Available We describe several experiments that were conducted to assess the viability of data pooling as a means to improve speech-recognition performance for under-resourced languages. Two groups of closely related languages from the Southern Bantu language...

  2. "Teisele poole" Agambeniga ja Agambenita / Ragne Nukk

    Index Scriptorium Estoniae

    Nukk, Ragne, 1984-

    2012-01-01

    Tallinna Fotokuu rahvusvahelise fotonäituse "Teisele poole" ideeliste lähtekohtade tõlgendamisest. Autor kõrvutab Adam Budaki kuraatornäituse aluseks olnud Giorgio Agambeni esseed „Viimne kohtupäev“ näitusel eksponeeritud piltidega

  3. 7 CFR 1033.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... association and it fulfills the following conditions: (1) The aggregate monthly quantity supplied by all... or aseptically-processed fluid milk products. (c) A supply plant from which the quantity of bulk... operator of a supply plant located within the marketing area may include deliveries to pool distributing...

  4. Benthic assemblages of rock pools in northern Portugal: seasonal and between-pool variability

    Directory of Open Access Journals (Sweden)

    Iacopo Bertocci

    2012-11-01

    Full Text Available We investigated the seasonal (winter vs summer and within season and spatial (between-pool variability of benthic assemblages of rock pools at mid-intertidal level along the shore of Viana do Castelo (North Portugal. Physical traits of rock pools, including size, depth and position along the shore, were also compared between pools. While pools did not differ for any of the examined physical traits, results indicated a clear seasonal difference in the structure of assemblages, including a total of 49 macroalgal and 13 animal taxa. This finding was driven by six taxa that are more abundant in winter (the reef-forming polychaete Sabellaria alveolata, the articulated coralline algae Corallina spp., the brown alga Bifurcaria bifurcata, the encrusting coralline alga Lithophyllum incrustans, the red alga Chondracanthus acicularis and the grazing snails Gibbula spp. and four algal taxa that are more abundant in summer (the invasive brown Sargassum muticum, the green Ulva spp., the kelp Laminaria ochroleuca and the filamentous red Ceramium spp.. These data provide a new contribution to the knowledge of rock pool systems and have potential implications for monitoring programmes aimed at assessing ecological modifications related to natural and anthropogenic disturbances and for identifying processes responsible for the variability of rock pool assemblages.

  5. Generalizing Pooling Functions in CNNs: Mixed, Gated, and Tree.

    Science.gov (United States)

    Lee, Chen-Yu; Gallagher, Patrick; Tu, Zhuowen

    2018-04-01

    In this paper, we seek to improve deep neural networks by generalizing the pooling operations that play a central role in the current architectures. We pursue a careful exploration of approaches to allow pooling to learn and to adapt to complex and variable patterns. The two primary directions lie in: (1) learning a pooling function via (two strategies of) combining of max and average pooling, and (2) learning a pooling function in the form of a tree-structured fusion of pooling filters that are themselves learned. In our experiments every generalized pooling operation we explore improves performance when used in place of average or max pooling. We experimentally demonstrate that the proposed pooling operations provide a boost in invariance properties relative to conventional pooling and set the state of the art on several widely adopted benchmark datasets. These benefits come with only a light increase in computational overhead during training (ranging from additional 5 to 15 percent in time complexity) and a very modest increase in the number of model parameters (e.g., additional 1, 9, and 27 parameters for mixed, gated, and 2-level tree pooling operators, respectively). To gain more insights about our proposed pooling methods, we also visualize the learned pooling masks and the embeddings of the internal feature responses for different pooling operations. Our proposed pooling operations are easy to implement and can be applied within various deep neural network architectures.

  6. Corium quench in deep pool mixing experiments

    International Nuclear Information System (INIS)

    Spencer, B.W.; McUmber, L.; Gregorash, D.; Aeschlimann, R.; Sienicki, J.J.

    1985-01-01

    The results of two recent corium-water thermal interaction (CWTI) tests are described in which a stream of molten corium was poured into a deep pool of water in order to determine the mixing behavior, the corium-to-water heat transfer rates, and the characteristic sizes of the quenched debris. The corium composition was 60% UO 2 , 16% ZrO 2 , and 24% stainless steel by weight; its initial temperature was 3080 K, approx.160 K above the oxide phase liquidus temperature. The corium pour stream was a single-phase 2.2 cm dia liquid column which entered the water pool in film boiling at approx.4 m/s. The water subcooling was 6 and 75C in the two tests. Test results showed that with low subcooling, rapid steam generation caused the pool to boil up into a high void fraction regime. In contrast, with large subcooling no net steam generation occurred, and the pool remained relatively quiescent. Breakup of the jet appeared to occur by surface stripping. In neither test was the breakup complete during transit through the 32 cm deep water pool, and molten corium channeled to the base where it formed a melt layer. The characteristic heat transfer rates measured 3.5 MJ/s and 2.7 MJ/s during the fall stage for small and large subcooling, respectively; during the initial stage of bed quench, the surface heat fluxes measured 2.4 MW/m 2 and 3.7 MW/m 2 , respectively. A small mass of particles was formed in each test, measuring typically 0.1 to 1 mm and 1 to 5 mm dia for the large and small subcooling conditions, respectively. 9 refs., 13 figs., 1 tab

  7. Suncatcher and cool pool. Project report

    Energy Technology Data Exchange (ETDEWEB)

    Hammond, J.

    1981-03-01

    The Suncatcher is a simple, conical solar concentrating device that captures light entering clerestory windows and directs it onto thermal storage elements at the back of a south facing living space. The cone shape and inclination are designed to capture low angle winter sunlight and to reflect away higher angle summer sunlight. It is found that winter radiation through a Suncatcher window is 40 to 50% higher than through an ordinary window, and that the average solar fraction is 59%. Water-filled steal culvert pipes used for thermal storage are found to undergo less stratification, and thus to be more effective, when located where sunlight strikes the bottom rather than the top. Five Suncatcher buildings are described. Designs are considered for 32/sup 0/, 40/sup 0/ and 48/sup 0/ north latitude, and as the latitude increases, the inclination angle of the cone should be lowered. The Cool Pool is an evaporating, shaded roof pond which thermosiphons cool water into water-filled columns within a building. Preliminary experiments indicate that the best shade design has unimpeded north sky view, good ventilation, complete summer shading, a low architectural profile, and low cost attic vent lowers work. Another series of experiments established the satisfactory performance of the Cool Pool on a test building using four water-filled cylinders, two cylinders, and two cylinders connected to the Cool Pool through a heat exchanger. Although an unshaded pool cools better at night than a shaded one, daytime heat gain far offsets this advantage. A vinyl waterbag heat exchanger was developed for use with the Cool Pool. (LEW)

  8. DC-bus voltage control of grid-connected voltage source converter by using space vector modulated direct power control under unbalanced network conditions

    DEFF Research Database (Denmark)

    Xiao, Lei; Huang, Shoudao; Lu, Kaiyuan

    2013-01-01

    Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load. In this......Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load....... In this study, a new proportional-integral-resonant (PI-RES) controller-based, space vector modulated direct power control topology is proposed to suppress the dc-bus voltage ripple and in the same time, controlling effectively the instantaneous power of the VSC. A special ac reactive power reference component...... is introduced in the controller, which is necessary in order to reduce the dc-bus voltage ripple and active power harmonics at the same time. The proposed control topology is implemented in the lab. Simulation and experimental results are provided to validate its performance and the analysis presented...

  9. An Interaction Between the Effects of Bilingualism and Cross-linguistic Similarity in Balanced and Unbalanced Bilingual Adults' L2 Mandarin Word-Reading Production.

    Science.gov (United States)

    Hsu, Hsiu-Ling

    2017-08-01

    We conducted three experiments investigating in more detail the interaction between the two effects of bilingualism and L1-L2 similarity in the speech performance of balanced and unbalanced bilinguals. In Experiment 1, L1 Mandarin monolinguals and two groups of Hakka and Minnan balanced bilinguals (Hakka: more similar to Mandarin) performed a non-contextual single-character reading task in Mandarin, which required more inhibitory control. The two bilingual groups outperformed the monolinguals, regardless of their L1 background. However, the bilingual advantage was not found in a contextual multi-word task (Experiment 2), but instead the effect of cross-linguistic similarity emerged. Furthermore, in Experiment 3, the Hakka unbalanced bilinguals showed an advantage in the non-contextual task, while their Minnan counterparts did not, and the impact of L1-L2 similarity emerged in both tasks. These results unveiled the way the two effects dynamically interplayed depending on the task contexts and the relative degrees of using L1 and L2.

  10. Horizontal above-rack pool storage

    International Nuclear Information System (INIS)

    Moscardini, R.L.

    1993-08-01

    This report describes a unique method for storing spent, six year out of core, fuel at a prototypical PWR nuclear power station. The study describes a conceptual design, with favorable structural, thermal and criticality technical evaluations. However, economic considerations and licensing risks are judged to be less favorable. The concept study prescribes a fuel over fuel arrangement in an existing Spent Fuel Pool (SFP) with full maintenance of ALARA principles. This concept study is specific to a prototypical pool design, but may easily be projected to other nuclear facilities with other SFP conditions. For the prototypical PWR, the conceptual fuel bridge design will store over 200 additional fuel assemblies without significant facility modifications and for an indefinite time period

  11. Sodium pool fire model for CONACS code

    International Nuclear Information System (INIS)

    Yung, S.C.

    1982-01-01

    The modeling of sodium pool fires constitutes an important ingredient in conducting LMFBR accident analysis. Such modeling capability has recently come under scrutiny at Westinghouse Hanford Company (WHC) within the context of developing CONACS, the Containment Analysis Code System. One of the efforts in the CONACS program is to model various combustion processes anticipated to occur during postulated accident paths. This effort includes the selection or modification of an existing model and development of a new model if it clearly contributes to the program purpose. As part of this effort, a new sodium pool fire model has been developed that is directed at removing some of the deficiencies in the existing models, such as SOFIRE-II and FEUNA

  12. Pool Boiling CHF in Inclined Narrow Annuli

    International Nuclear Information System (INIS)

    Kang, Myeong Gie

    2010-01-01

    Pool boiling heat transfer has been studied extensively since it is frequently encountered in various heat transfer equipment. Recently, it has been widely investigated in nuclear power plants for application to the advanced light water reactors designs. Through the review on the published results it can be concluded that knowledge on the combined effects of the surface orientation and a confined space on pool boiling heat transfer is of great practical importance and also of great academic interest. Fujita et al. investigated pool boiling heat transfer, from boiling inception to the critical heat flux (CHF, q' CHF ), in a confined narrow space between heated and unheated parallel rectangular plates. They identified that both the confined space and the surface orientation changed heat transfer much. Kim and Suh changed the surface orientation angles of a downward heating rectangular channel having a narrow gap from the downward-facing position (180 .deg.) to the vertical position (90 .deg.). They observed that the CHF generally decreased as the inclination angle (θ ) increased. Yao and Chang studied pool boiling heat transfer in a confined heat transfer for vertical narrow annuli with closed bottoms. They observed that when the gap size ( s ) of the annulus was decreased the effect of space confinement to boiling heat transfer increased. The CHF was occurred at much lower value for the confined space comparing to the unconfined pool boiling. Pool boiling heat transfer in narrow horizontal annular crevices was studied by Hung and Yao. They concluded that the CHF decreased with decreasing gap size of the annuli and described the importance of the thin film evaporation to explain the lower CHF of narrow crevices. The effect of the inclination angle on the CHF on countercurrent boiling in an inclined uniformly heated tube with closed bottoms was also studied by Liu et al. They concluded that the CHF reduced with the inclination angle decrease. A study was carried out

  13. Review and assessment of pool scrubbing models

    International Nuclear Information System (INIS)

    Herranz, L.E.; Escudero, M.J.; Peyres, V.; Polo, J.; Lopez-Jimenez, J.

    1996-01-01

    Decontamination of fission products bearing bubbles as they through aqueous pools becomes a crucial phenomenon for source term evaluation of hypothetical risk dominant sequences of Light Water Reactors. In the present report a peer review and assessment of models encapsulated in SPARC andBUSCA codes is presented. Several aspects of pool scrubbing have been addressed: particle removal, fission product vapour retention and bubble hydrodynamics. Particular emphasis has been given to the close link between retention and hydrodynamics, from both modelling and experimental point of view. In addition, RHR and SGTR sequences were simulated with SPARC90 and BUSCA-AUG92 codes, and their results were compared with those obtained with MAAP 3.0B.As a result of this work, model capabilities and shortcomings have beenassessed and some areas susceptible of further research have been identified.(Author) 73 refs

  14. Review and assessment of pool scrubbing models

    International Nuclear Information System (INIS)

    Herranz, L.E.; Escudero, M.J.; Peyres, V.; Polo, J.; Lopez, J.

    1996-01-01

    Decontamination of fission products bearing bubbles as they pass through aqueous pools becomes a crucial phenomenon for source term evaluation of hypothetical risk dominant sequences of Light Water Reactors. In the present report a peer review and assessment of models encapsulated in SPARC and BUSCA codes is presented. Several aspects of pool scrubbing have been addressed: particle removal, fission product vapour retention and bubble hydrodynamics. Particular emphasis has been given to the close link between retention and hydrodynamics, from both modelling and experimental point of view. In addition, RHR and SGTR sequences were simulated with SPARC90 and BUSCA-AUG92 codes, and their results were compared with those obtained with MAAP 3.0B. As a result of this work, model capabilities and shortcomings have been assessed and some areas susceptible of further research have been identified. (Author) 73 refs

  15. Review and assessment of pool scrubbing models

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, L.E.; Escudero, M.J.; Peyres, V.; Polo, J.; Lopez, J.

    1996-07-01

    Decontamination of fission products bearing bubbles as they pass through aqueous pools becomes a crucial phenomenon for source term evaluation of hypothetical risk dominant sequences of Light Water Reactors. In the present report a peer review and assessment of models encapsulated in SPARC and BUSCA codes is presented. Several aspects of pool scrubbing have been addressed: particle removal, fission product vapour retention and bubble hydrodynamics. Particular emphasis has been given to the close link between retention and hydrodynamics, from both modelling and experimental point of view. In addition, RHR and SGTR sequences were simulated with SPARC90 and BUSCA-AUG92 codes, and their results were compared with those obtained with MAAP 3.0B. As a result of this work, model capabilities and shortcomings have been assessed and some areas susceptible of further research have been identified. (Author) 73 refs.

  16. Pricing Electricity in Pools With Wind Producers

    DEFF Research Database (Denmark)

    Morales González, Juan Miguel; Conejo, A. J.; Kai Liu

    2012-01-01

    This paper considers an electricity pool that includes a significant number of wind producers and is cleared through a network-constrained auction, one day in advance and on an hourly basis. The hourly auction is formulated as a two-stage stochastic programming problem, where the first stage...... represents the clearing of the market and the second stage models the system operation under a number of plausible wind production realizations. This formulation co-optimizes energy and reserve, and allows deriving both pool energy prices and balancing energy prices. These prices result in both cost recovery...... for producers and revenue reconciliation. A case study of realistic size is used to illustrate the functioning of the proposed pricing scheme....

  17. Pool type liquid metal fast breeder reactors

    International Nuclear Information System (INIS)

    Guthrie, B.M.

    1978-08-01

    Various technical aspects of the liquid metal fast breeder reactor (LMFBR), specifically pool type LMFBR's, are summarized. The information presented, for the most part, draws upon existing data. Special sections are devoted to design, technical feasibility (normal operating conditions), and safety (accident conditions). A survey of world fast reactors is presented in tabular form, as are two sets of reference reactor parameters based on available data from present and conceptual LMFBR's. (auth)

  18. Condensation of vapor bubble in subcooled pool

    Science.gov (United States)

    Horiuchi, K.; Koiwa, Y.; Kaneko, T.; Ueno, I.

    2017-02-01

    We focus on condensation process of vapor bubble exposed to a pooled liquid of subcooled conditions. Two different geometries are employed in the present research; one is the evaporation on the heated surface, that is, subcooled pool boiling, and the other the injection of vapor into the subcooled pool. The test fluid is water, and all series of the experiments are conducted under the atmospheric pressure condition. The degree of subcooling is ranged from 10 to 40 K. Through the boiling experiment, unique phenomenon known as microbubble emission boiling (MEB) is introduced; this phenomenon realizes heat flux about 10 times higher than the critical heat flux. Condensation of the vapor bubble is the key phenomenon to supply ambient cold liquid to the heated surface. In order to understand the condensing process in the MEB, we prepare vapor in the vapor generator instead of the evaporation on the heated surface, and inject the vapor to expose the vapor bubble to the subcooled liquid. Special attention is paid to the dynamics of the vapor bubble detected by the high-speed video camera, and on the enhancement of the heat transfer due to the variation of interface area driven by the condensation.

  19. Gene pool conservation of teak in Myanmar

    International Nuclear Information System (INIS)

    Tin-Tun

    1995-01-01

    Myanmar with an area of 261, 228 Sq. miles is endowed with various types of forests which occupied nearly 50% of the country. Teak (Tectona grandis Linn. f.) is one of the most valuable timber species for its excellent wood quality and properties which are not observed with other timbers. Gene pool can be defined as a group of individual trees growing over a wide range of environmental conditions, and constituting different genetic complexes which can be transmitted to the offsprings. Topics such as: objectives of gene pool conservation, genetically improved seeds for large scale forest plantations, methodology of conservation, are discussed in the article. Myanmar teak dominates the world's teak market, and thus it is crucial to maintain the superiority in the conservation of gene complexes of teak. To some extent, the conservation of gene pools of teak and tree improvements are being undertaken by the Forest Research Institute of Myanmar. It is felt that the dissemination of the philosophy and concept of gene conservation to the personal involved in the forestry activities of the country are still inadequate

  20. African American women and sexually transmitted infections: The contextual influence of unbalanced sex ratios and individual risk behaviors.

    Science.gov (United States)

    Oser, Carrie B; Pullen, Erin; Stevens-Watkins, Danelle; Perry, Brea L; Havens, Jennifer R; Staton-Tindall, Michele; Leukefeld, Carl G

    2017-10-01

    This study uses data from 564 African American women to examine the correlates of lifetime prevalence of a sexually transmitted infection (STI). Specifically, we test the effects of perceptions about the availability of African American males, five partner characteristics, and drug history. At the bivariate-level, women with an STI diagnosis were significantly more likely to have dated a man who was married, older, had sex with another man, involved in concurrent partnerships, and had been incarcerated. About half of the participants stated it was difficult to find an eligible African American male and attributed the limited pool of same-race partners to drug trafficking, a lack of monogamy, and high rates of incarceration. Multivariate analyses revealed having dated a man who had concurrent sexual partnerships or had been incarcerated, as well as drug use during sex were positively associated with ever having an STI. Individual and contextual implications are addressed.

  1. POOL WATER TREATMENT AND COOLING SYSTEM DESCRIPTION DOCUMENT

    International Nuclear Information System (INIS)

    King, V.

    2000-01-01

    The Pool Water Treatment and Cooling System is located in the Waste Handling Building (WHB), and is comprised of various process subsystems designed to support waste handling operations. This system maintains the pool water temperature within an acceptable range, maintains water quality standards that support remote underwater operations and prevent corrosion, detects leakage from the pool liner, provides the capability to remove debris from the pool, controls the pool water level, and helps limit radiological exposure to personnel. The pool structure and liner, pool lighting, and the fuel staging racks in the pool are not within the scope of the Pool Water Treatment and Cooling System. Pool water temperature control is accomplished by circulating the pool water through heat exchangers. Adequate circulation and mixing of the pool water is provided to prevent localized thermal hotspots in the pool. Treatment of the pool water is accomplished by a water treatment system that circulates the pool water through filters, and ion exchange units. These water treatment units remove radioactive and non-radioactive particulate and dissolved solids from the water, thereby providing the water clarity needed to conduct waste handling operations. The system also controls pool water chemistry to prevent advanced corrosion of the pool liner, pool components, and fuel assemblies. Removal of radioactivity from the pool water contributes to the project ALARA (as low as is reasonably achievable) goals. A leak detection system is provided to detect and alarm leaks through the pool liner. The pool level control system monitors the water level to ensure that the minimum water level required for adequate radiological shielding is maintained. Through interface with a demineralized water system, adequate makeup is provided to compensate for loss of water inventory through evaporation and waste handling operations. Interface with the Site Radiological Monitoring System provides continuous

  2. Infections Unlikely to be Spread Through Swimming Pools

    Science.gov (United States)

    ... Water Home Infections Unlikely to be Spread Through Swimming Pools Language: English (US) Español (Spanish) Recommend on ... included below. Infections Unlikely to be Spread by Swimming Pools Head Lice Head lice are unlikely to ...

  3. Thermal analyses of solar swimming pool heating in Pakistan

    International Nuclear Information System (INIS)

    Ahmad, I.

    2011-01-01

    Hotels and swimming clubs in Pakistan pay huge gas bills for heating Swimming pools in winter. Winter days in most parts of Pakistan remain sunny and unglazed low cost solar collectors may be used to extend the swimming season. Installing the pool in a wind-protected area, which receives unobstructed solar radiation, may further reduce the size of the solar collectors required to heat the swimming pools. The pools should be covered with plastic sheet to eliminate evaporative heat losses and to prevent dust and tree leaves falling in the pool. The results of the thermal analysis show that in some parts of the country, a solar exposed pool can maintain comfortable temperature simply by using a plastic sheet on the pool surface. On the other hand, there are cities where solar collector array equal to twice the surface area of the pool is required to keep desired temperature in winter. (author)

  4. Analysis of sodium pool fire in SFEF for assessing the limiting pool fire

    International Nuclear Information System (INIS)

    Mangarjuna Rao, P.; Ramesh, S.S.; Nashine, B.K.; Kasinathan, N.; Chellapandi, P.

    2011-01-01

    Accidental sodium leaks and resultant sodium fires in Liquid Metal Fast Breeder Reactor (LMFBR) systems can create a threat to the safe operation of the plant. To avoid this defence-in depth approach is implemented from the design stage of reactor itself. Rapid detection of sodium leak and fast dumping of the sodium into the storage tank of a defective circuit, leak collection trays, adequate lining of load bearing structural concrete and extinguishment of the sodium fire are the important defensive measures in the design, construction and operation of a LMFBR for protection against sodium leaks and their resultant fires. Evaluation of sodium leak events and their consequences by conducting large scale engineering experiments is very essential for effective implementation of the above protection measures for sodium fire safety. For this purpose a Sodium Fire Experimental Facility (SFEF) is constructed at SED, IGCAR. SFEF is having an experimental hall of size 9 m x 6 m x 10 m with 540 m 3 volume and its design pressure is 50 kPa. It is a concrete structure and provided with SS 304 liner, which is fixed to the inside surfaces of walls, ceiling and floor. A leak tight door of size (1.8 m x 2.0 m) is provided to the experimental hall and the facility is provided with a sodium equipment hall and a control room. Experimental evaluation of sodium pool fire consequences is an important activity in the LMFBR sodium fire safety related studies. An experimental program has been planned for different types of sodium fire studies in SFEF. A prior to that numerical analysis have been carried out for enclosed sodium pool fires using SOFIRE-II sodium pool fire code for SFEF experimental hall configuration to evaluate the limiting pool fire. This paper brings out results of the analysis carried out for this purpose. Limiting pool fire of SFEF depends on the exposed surface area of the pool, amount of sodium in the pool, oxygen concentration and initial sodium temperature. Limiting

  5. (Important hygienic aspects for swimming pools (author's transl))

    Energy Technology Data Exchange (ETDEWEB)

    Somosi, G

    1981-01-01

    The major epidemics which occurred in Hungary and originated from water in swimming pools are reported. The difficulties encountered in producing epidemiological evidence and in monitoring infections originating from water in swimming pools are mentioned. The possibilities of controlling the water quality in swimming pools and of preventing infections are discussed. Reference is made to the existing bacteriological limit values in Hungary to be observed in the recirculation of water in swimming pools.

  6. NACUBO's Guide to Unitizing Investment Pools. Second Edition

    Science.gov (United States)

    Wheeler, Mary S.

    2011-01-01

    The National Association of College and University Business Officers' (NACUBO's) "Guide to Unitizing Investment Pools" addresses the principles and concepts for administering a consolidated investment pool. Unitization is the mechanism by which investment funds are pooled to maximize investment efficiencies and provide information for donors,…

  7. A skeleton for distributed work pools in Eden

    DEFF Research Database (Denmark)

    Dieterle, Mischa; Berthold, Jost; Loogen, Rita

    2010-01-01

    We present a flexible skeleton for implementing distributed work pools in our parallel functional language Eden. The skeleton manages a pool of tasks (work pool) in a distributed manner using a demand-driven work stealing approach for load balancing. All coordination is done locally within...

  8. Opportunities and challenges when pooling milk samples using ELISA

    DEFF Research Database (Denmark)

    Græsbøll, Kaare; Andresen, Lars Ole; Hisham Beshara Halasa, Tariq

    2017-01-01

    -positive samples by pooling. To illustrate this, the sensitivity of antibody ELISA on pooled samples of bovine milk for Salmonella Dublin, Mycobacterium avium spp. paratuberculosis, and bovine virus diarrhea was tested. For these milk assays, the analytical sensitivity decreased rapidly with increasing pool sizes...

  9. 17 CFR 4.22 - Reporting to pool participants.

    Science.gov (United States)

    2010-04-01

    ..., the financial statements are not required to include consolidated information for all series. (7) For... event that the International Financial Reporting Standards require consolidated financial statements for... reporting pool's consolidated financial statements. (ii) The commodity pool operator of a pool that meets...

  10. 48 CFR 873.114 - Best value pool.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Best value pool. 873.114... SUPPLEMENTARY REGULATIONS SIMPLIFIED ACQUISITION PROCEDURES FOR HEALTH-CARE RESOURCES 873.114 Best value pool... solicitation. These vendors constitute the best value pool. This determination is within the sole discretion of...

  11. Measurements in large JP-4 pool fires

    International Nuclear Information System (INIS)

    Keltner, N.R.; Kent, L.A.; Schneider, M.E.

    1987-01-01

    Over the past four years, Sandia National Laboratories has conducted a number of large pool fire tests to evaluate the design of radioactive material (RAM) shipping containers. Some of these tests have been designed to define the thermal environment and some have been used for certification testing. In each test there have been a number of fire diagnostic measurements. The simplest sets of diagnostics have involved measurements of temperature at several elevations on arrays of towers, measurements of hot wall heat flux with small calorimeters suspended from the towers, the average fuel recession rate, and the wind speed and direction. The most complex sets of diagnostics have included the above and in various tests added radiometers in the lower flame zone, centerline velocity measurements at a number of elevations, radiometers and calorimeters at the fuel surface, large cylindrical and flat plate calorimeters, infrared imaging, time resolved fuel recession rates, and a variety of soot particle concentration and size measurements made in the plume with a tethered balloon and an instrumented airplane. All of the large fires have been conducted in a 9.1 m by 18.3 m pool using JP-4 as the fuel. Typical duration is one-half hour. Covering all of the results is beyond the scope of a single paper. Conditionally sampled temperature and velocity measurements from one fire will be presented; for this fire, a 20 cm layer of fuel was floated on 61 cm of water. Pool surface heat flux, fuel recession rate data, and smoke emission data from a second fire are given. Because the wind has a strong effect on the temperature and velocity measurements, conditional sampling has been used to try to obtain data during periods of low winds. 10 refs., 3 figs

  12. Balanced and Unbalanced Circulations in a Primitive Equation Simulation of a Midlatitude MCC. Part I: The Numerical Simulation.

    Science.gov (United States)

    Olsson, Peter Q.; Cotton, William R.

    1997-02-01

    A midlatitude mesoscale convective complex (MCC), which occurred over the central United States on 23-24 June 1985, was simulated using the Regional Atmospheric Modeling System (RAMS). The multiply nested-grid simulation agreed reasonably well with surface, upper-air, and satellite observations and ground-based radar plots. The simulated MCC had a typical structure consisting of a leading line of vigorous convection and a trailing region of less intense stratiform rainfall. Several other characteristic MCC circulations were also simulated: a divergent cold pool in the lower troposphere, midlevel convergence coupled with a relatively cool descending rear-inflow jet, and relatively warm updraft structure, and a cold divergent anticyclone in the tropopause region. Early in the MCC simulation, a mesoscale convectively induced vortex (MCV) formed on the eastern edge of the convective line. While frequently associated with MCCs and other mesoscale convective systems (MCSs), MCVs are more typically reported in the mature and decaying stages of the life cycle. Several hours later, a second MCV formed near the opposite end of the convective line, and by the mature phase of the MCC, these MCVs were embedded within a more complex system-wide vortical flow in the lower troposphere.Analysis of the first MCV during its incipient phase indicates that the vortex initially formed near the surface by convergence/stretching of the large low-level ambient vertical vorticity in this region. Vertical advection appeared largely responsible for the upward extension of this MCV to about 3.5 km above the surface, with tilting of horizontal vorticity playing a secondary role. This mechanism of MCV formation is in contrast to recent idealized high-resolution squall line simulations, where MCVs were found to result from the tilting into the vertical of storm-induced horizontal vorticity formed near the top of the cold pool.Another interesting aspect of the simulation was the development of a

  13. Gated cardiac blood pool studies in arrhythmias

    International Nuclear Information System (INIS)

    Itti, R.; Casset, D.; Philippe, L.; Cosnay, P.; Fauchier, J.P.

    1988-01-01

    Biventricular phase analysis a gated blood pool studies may help to solve two fundamental questions raised by patients suffering from arrhythmias: localization of an electrical cardiac activation abnormality by means of contraction mapping and assesment of an underlying organic disease using the phase histograms and their standard deviations. Three groups of patients have been evaluated to demonstrate the usefulness of radioisotopic techniques in arrhythmias: 36 patients with a Wolff-Parkinson-White syndrom, 27 patients studied during a ventricular tachycardia attack and 32 patients suspected of arrhythmogenic ventricular dysplasia. Correlations with invasive electrophysiologic studies are presented and the diagnostic and therapeutic implications of these results are discussed [fr

  14. Pool boiling visualization on open microchannel surfaces

    Directory of Open Access Journals (Sweden)

    Kaniowski Robert

    2017-01-01

    Full Text Available The paper presents visualization investigations into pool boiling heat transfer for open minichannel surfaces. The experiments were carried out wih saturated water at atmospheric pressure. Parallel microchannels fabricated by machining were about 0.3 mm wide and 0.2 to 0.4 mm deep. High-speed videos were used as an aid to understanding the heat transfer mechanism. The visualization study aimed at identifying nucleation sites of the departing bubbles and determining their diameters and frequency at various superheats.

  15. Simulation of a pool type research reactor

    International Nuclear Information System (INIS)

    Oliveira, Andre Felipe da Silva de; Moreira, Maria de Lourdes

    2011-01-01

    Computational fluid dynamic is used to simulate natural circulation condition after a research reactor shutdown. A benchmark problem was used to test the viability of usage such code to simulate the reactor model. A model which contains the core, the pool, the reflector tank, the circulation pipes and chimney was simulated. The reactor core contained in the full scale model was represented by a porous media. The parameters of porous media were obtained from a separate CFD analysis of the full core model. Results demonstrate that such studies can be carried out for research and test of reactors design. (author)

  16. Gated cardiac blood pool studies in arrhythmias

    Energy Technology Data Exchange (ETDEWEB)

    Itti, R.; Casset, D.; Philippe, L.; Cosnay, P.; Fauchier, J.P.

    1988-01-01

    Biventricular phase analysis a gated blood pool studies may help to solve two fundamental questions raised by patients suffering from arrhythmias: localization of an electrical cardiac activation abnormality by means of contraction mapping and assesment of an underlying organic disease using the phase histograms and their standard deviations. Three groups of patients have been evaluated to demonstrate the usefulness of radioisotopic techniques in arrhythmias: 36 patients with a Wolff-Parkinson-White syndrom, 27 patients studied during a ventricular tachycardia attack and 32 patients suspected of arrhythmogenic ventricular dysplasia. Correlations with invasive electrophysiologic studies are presented and the diagnostic and therapeutic implications of these results are discussed.

  17. Pool film boiling heat transfer, 5

    International Nuclear Information System (INIS)

    Sakurai, A.; Shiotsu, M.; Hata, K.

    1981-01-01

    Steady minimum film boiling heat flux and temperature were experimentally studied for a horizontal cylinder test heater in a pool of saturated water under pressures ranging from 0.1 to 2 MPa. Minimum temperature of film boiling may be determined by hydrodynamic Taylor instability for the pressures lower than around 1.0 MPa and by homogeneous nucleation temperature for the higher pressures. However, conventional correlations of minimum heat flux based on the hydrodynamic Taylor instability cannot at all predict the pressure dependency of the experimental data in the lower pressure region. Semi-empirical equation of the minimum heat flux based on the hydrodynamic Taylor instability was given. (author)

  18. Swimming pool reactor reliability and safety analysis

    International Nuclear Information System (INIS)

    Li Zhaohuan

    1997-01-01

    A reliability and safety analysis of Swimming Pool Reactor in China Institute of Atomic Energy is done by use of event/fault tree technique. The paper briefly describes the analysis model, analysis code and main results. Meanwhile it also describes the impact of unassigned operation status on safety, the estimation of effectiveness of defense tactics in maintenance against common cause failure, the effectiveness of recovering actions on the system reliability, the comparison of occurrence frequencies of the core damage by use of generic and specific data

  19. A Modular Cascaded Multilevel Inverter Based Shunt Hybrid Active Power Filter for Selective Harmonic and Reactive Power Compensation Under Distorted/Unbalanced Grid Voltage Conditions

    Directory of Open Access Journals (Sweden)

    T. Demirdelen

    2016-10-01

    Full Text Available In recent years, shunt hybrid active power filters are being increasingly considered as a viable alternative to both passive filters and active power filters for compensating harmonics. In literature, their applications are restricted to balanced systems and low voltage applications and therefore not for industrial applications. This paper investigates the performance of a modular cascaded multilevel inverter based Shunt Hybrid Active Power Filter (SHAPF for reactive power compensation and selective harmonics elimination under distorted/unbalanced grid voltage conditions in medium voltage levels. In the proposed control method, reactive power compensation is achieved successfully with a perceptible amount and the performance results of harmonic compensation are satisfactory. Theoretical analysis and simulation results are obtained from an actual industrial network model in PSCAD. The simulation results are presented for a proposed system in order to demonstrate that the harmonic compensation performance meets the IEEE-519 standard.

  20. Studies of the composition, tribology and wetting behavior of silicon nitride films formed by pulsed reactive closed-field unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Yao, Zh.Q.; Yang, P.; Huang, N.; Wang, J.; Wen, F.; Leng, Y.X.

    2006-01-01

    Silicon nitride films were formed by pulsed reactive closed-field unbalanced magnetron sputtering of high purity Si targets in an Ar-N 2 mixture. The effects of N 2 fraction on the chemical composition, and tribological and wetting behaviors were investigated. The films deposited at a high N 2 fraction were consistently N-rich. The surface microstructure changed from continuous granular surrounded by tiny void regions to a homogeneous and dense microstructure, and densitied as the N 2 fraction is increased. The as-deposited films have a relatively low friction coefficient and better wear resistance than 316L stainless steel under dry sliding friction and experienced only abrasive wear. The decreased surface roughness and increased nitrogen incorporation in the film give rise to increased contact angle with double-stilled water from 24 deg. to 49.6 deg. To some extent, the silicon nitride films deposited are hydrophilic in nature

  1. Enhanced Control for a Direct-driven Permanent Synchronous Generator Wind-power Generation System with Flywheel Energy Storage Unit Under Unbalanced Grid Fault

    DEFF Research Database (Denmark)

    Yao, Jun; Zhou, Te; Hu, Weihao

    2015-01-01

    This article presents an enhanced control strategy for a direct-driven permanent synchronous generator based wind-power generation system with a flywheel energy storage unit. The behaviors of the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit under......, the DC-link voltage oscillations can be effectively suppressed during the unbalanced grid fault by controlling the flywheel energy storage unit. Furthermore, a proportional–integral-resonant controller is designed for the flywheel motor to eliminate the oscillations in the DC-link voltage. Finally......, the proposed coordinated control strategy for the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit has been validated by the simulation results of a 1-MW direct-driven permanent magnet synchronous generator wind power generation system with a flywheel energy...

  2. Prader-Willi syndrome due to an unbalanced de novo translocation [t(15;19)(q12;p13.3)

    Science.gov (United States)

    Dang, Vy; Surampalli, Abhilasha; Manzardo, Ann M; Youn, Stephanie; Butler, Merlin G; Gold, June-Anne; Kimonis, Virginia

    2018-01-01

    Background and Aims Prader-Willi syndrome (PWS) is a complex, multisystem genetic disorder characterized by endocrine, neurologic and behavioral abnormalities. We report the first case of an unbalanced de-novo reciprocal translocation of chromosome 15 and 19: 45,XY,-15, der (19)t(15;19)(q12;p13.3) resulting in monosomy for the PWS chromosome critical region. We performed high resolution SNP microarray to characterize the breakpoints. Case report Our patient had several typical features for PWS including infantile hypotonia, a poor suck and feeding difficulties, tantrums, skin picking, compulsions, small hands and feet and food seeking but not hypopigmentation, a micropenis, cryptorchidism or obesity as common findings seen in PWS at the time of examination at 6 years of age. He had seizures noted from 1 to 3 years of age and marked cognitive delay. Results High resolution SNP microarray analysis identified an atypical PWS Type I deletion of chromosome 15 involving proximal breakpoint BP1. The deletion extended beyond the GABRB3 gene but was proximal to the usual distal breakpoint (BP3) within the 15q11-q13 region and GABRA5, GABRG3 and OCA2 genes were intact. Conclusion We report a case with atypical features for PWS associated with an unbalanced de-novo reciprocal translocation resulting in monosomy for the 15q11.1–15q12 with intact GABRA5, GABRG3 and OCA2 genes. No deletion of 19p13.3 band was detected therefore the patient was not at an increased risk of tumors from Peutz-Jeghers syndrome associated with a deletion of the STK11 gene. PMID:27894106

  3. Chinese nuclear insurance and Chinese nuclear insurance pool

    International Nuclear Information System (INIS)

    Gong Zhiqi

    2000-01-01

    Chinese Nuclear Insurance Started with Daya Bay Nuclear Power Station, PICC issued the insurance policy. Nuclear insurance cooperation between Chinese and international pool's organizations was set up in 1989. In 1996, the Chinese Nuclear Insurance Pool was prepared. The Chinese Nuclear Insurance Pool was approved by The Chinese Insurance Regulatory Committee in May of 1999. The principal aim is to centralize maximum the insurance capacity for nuclear insurance from local individual insurers and to strengthen the reinsurance relations with international insurance pools so as to provide the high quality insurance service for Chinese nuclear industry. The Member Company of Chinese Nuclear Pool and its roles are introduced in this article

  4. A method of measuring a molten metal liquid pool volume

    Science.gov (United States)

    Garcia, G.V.; Carlson, N.M., Donaldson, A.D.

    1990-12-12

    A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figs.

  5. Functional Dependence for Calculation of Additional Real-Power Losses in a Double-Wound Supply Transformer Caused by Unbalanced Active Inductive Load in a Star Connection with an Insulated Neutral

    Science.gov (United States)

    Kostinskiy, Sergey S.; Troitskiy, Anatoly I.

    2016-01-01

    This article deals with the problem of calculating the additional real-power losses in double-wound supply transformers with voltage class 6 (10)/0,4 kV, caused by unbalanced active inductive load connected in a star connection with an insulated neutral. When solving the problem, authors used the theory of electric circuits, method of balanced…

  6. Study of mixed convection in sodium pool

    International Nuclear Information System (INIS)

    Wang Zhou; Chen Yan

    1995-01-01

    The mixed convection phenomena in the sodium pool of fast reactor have been studied systematically by the two dimensional modeling method. A generalized concept of circumferential line in the cylindrical coordinates was proposed to overcome the three dimensional effect induced by the pool geometry in an analysis of two dimensional modeling. A method of sub-step in time was developed for solving the turbulent equations. The treatments on the boundary condition for the auxiliary velocity field have been proposed, and the explanation of allowing the flow function method to be used in the flow field in presence of a mass source term was given. As examples of verification, the experiments were conducted with water flow in a rectangular cavity. The results from theoretical analysis were applied to the numerical computation for the mixed convection in the cavity. The mechanism of stratified flow in the cavity was studied. A numerical calculation was carried out for the mixed convection in hot plenum of a typical fast reactor

  7. Visual attention and flexible normalization pools

    Science.gov (United States)

    Schwartz, Odelia; Coen-Cagli, Ruben

    2013-01-01

    Attention to a spatial location or feature in a visual scene can modulate the responses of cortical neurons and affect perceptual biases in illusions. We add attention to a cortical model of spatial context based on a well-founded account of natural scene statistics. The cortical model amounts to a generalized form of divisive normalization, in which the surround is in the normalization pool of the center target only if they are considered statistically dependent. Here we propose that attention influences this computation by accentuating the neural unit activations at the attended location, and that the amount of attentional influence of the surround on the center thus depends on whether center and surround are deemed in the same normalization pool. The resulting form of model extends a recent divisive normalization model of attention (Reynolds & Heeger, 2009). We simulate cortical surround orientation experiments with attention and show that the flexible model is suitable for capturing additional data and makes nontrivial testable predictions. PMID:23345413

  8. Hardening Stratum, the Bitcoin Pool Mining Protocol

    Directory of Open Access Journals (Sweden)

    Recabarren Ruben

    2017-07-01

    Full Text Available Stratum, the de-facto mining communication protocol used by blockchain based cryptocurrency systems, enables miners to reliably and efficiently fetch jobs from mining pool servers. In this paper we exploit Stratum’s lack of encryption to develop passive and active attacks on Bitcoin’s mining protocol, with important implications on the privacy, security and even safety of mining equipment owners. We introduce StraTap and ISP Log attacks, that infer miner earnings if given access to miner communications, or even their logs. We develop BiteCoin, an active attack that hijacks shares submitted by miners, and their associated payouts. We build BiteCoin on WireGhost, a tool we developed to hijack and surreptitiously maintain Stratum connections. Our attacks reveal that securing Stratum through pervasive encryption is not only undesirable (due to large overheads, but also ineffective: an adversary can predict miner earnings even when given access to only packet timestamps. Instead, we devise Bedrock, a minimalistic Stratum extension that protects the privacy and security of mining participants. We introduce and leverage the mining cookie concept, a secret that each miner shares with the pool and includes in its puzzle computations, and that prevents attackers from reconstructing or hijacking the puzzles.

  9. Estimated environmental radionuclide transfer and deposition into outdoor swimming pools

    International Nuclear Information System (INIS)

    Tagami, Kazumi; Nagata, Izumi; Sueki, Keisuke

    2014-01-01

    In 2011, a large radioactive discharge occurred at the Fukushima Daiichi nuclear power plant. This plant is located within a climatically temperate region where outdoor swimming pools are popular. Although it is relatively easy to decontaminate pools by refilling them with fresh water, it is difficult to maintain safe conditions given highly contaminated diurnal dust falls from the surrounding contaminated ground. Our objectives in this paper were to conduct daily radioactivity measurements, to determine the quantity of radioactive contaminants from the surrounding environment that invade outdoor pools, and to investigate the efficacy of traditional pool cleaners in removing radioactive contaminants. The depositions in the paper filterable particulates ranged from 0 to 62,5 Bq/m 2 /day, with the highest levels found in the southern Tohoku District containing Fukushima Prefecture and in the Kanto District containing Tokyo Metro. They were approximately correlated with the ground contamination. Traditional pool cleaners eliminated 99% of contaminants at the bottom of the pool, reducing the concentration to 41 Bq/m 2 after cleaning. Authors recommended the deposition or the blown radionuclides into outdoor swimming pools must be considered into pool regulations when the environments exactly polluted with radionuclides. - Highlights: • Deposition into outdoor swimming pool in a habitable areas estimated 72 Bq/m 2 /day. • More than 500 Bq/m 2 /day deposition will exceed our national guideline (10 Bq/l) of swimming pool. • Vacuum pool cleaner eliminates 99% radionuclides deposition

  10. Plant diversity associated with pools in natural and restored peatlands

    Directory of Open Access Journals (Sweden)

    N. Fontaine

    2007-06-01

    Full Text Available This study describes plant assemblages associated with the edges of peatland pools. We conducted inventories in six natural peatlands in the province of Québec (Canada in order to measure the contribution of pools to species diversity in climatic regions where peatlands are used for peat extraction. We also carried out vegetation surveys in a peatland that has been restored after peat extraction/harvesting to determine whether pool vegetation establishes along the edges of created pools when dry surface restoration techniques only are used. Pools enhanced plant species richness in natural peatlands. Around created pools, species associated with natural pools were still absent, and non-bog species were present, six years after restoration. On this basis, we emphasise the importance of preserving natural peatlands with pools. In order to restore fully the plant diversity associated with peatlands at harvested sites, it may be necessary to modify pool excavation techniques so that created pools resemble more closely those in natural peatlands. Active introduction of the plant species or communities associated with natural pools may also be needed; candidate species for North America include Andromeda glaucophylla, Cladopodiella fluitans, Carex limosa, Eriophorum virginicum, Rhynchospora alba and Sphagnum cuspidatum.

  11. Life cycle environmental implications of residential swimming pools.

    Science.gov (United States)

    Forrest, Nigel; Williams, Eric

    2010-07-15

    Ownership of private swimming pools in the U.S. grew 2 to 4% per annum from 1997 to 2007. The environmental implications of pool ownership are analyzed by hybrid life cycle assessment (LCA) for nine U.S. cities. An operational model is constructed estimating consumption of chemicals, water, and energy for a typical residential pool. The model incorporates geographical climatic variations and upstream water and energy use from electricity and water supply networks. Results vary considerably by city: a factor of 5-6 for both water and energy use. Water use is driven by aridness and length of the swimming season, while energy use is mainly driven by length of the swimming season. Water and energy impacts of pools are significant, particularly in arid climates. In Phoenix for example pools account for 22% and 13% of a household's electricity and water use, respectively. Measures to reduce water and energy use in pools such as optimizing the pump schedule and covering the pool in winter can realize greater savings than many common household efficiency improvements. Private versus community pools are also compared. Community pools in Phoenix use 60% less swimming pool water and energy per household than subdivisions without community pools.

  12. Reduction of the pool-top radiation level in HANARO

    International Nuclear Information System (INIS)

    Lee, Choong-Sung; Park, Sang-Jun; Kim, Heonil; Park, Yong-Chul; Choi, Young-San

    1999-01-01

    HANARO is an open-tank-in-pool type reactor. Pool water is the only shielding to minimize the pool top radiation level. During the power ascension test of HANARO, the measured pool top radiation level was higher than the design value because some of the activation products in the coolant reached the pool surface. In order to suppress this rising coolant, the hot water layer system (HWL) was designed and installed to maintain l.2 meter-deep hot water layer whose temperature is 5degC higher than that of the underneath pool surface. After the installation of the HWL system, however, the radiation level of the pool-top did not satisfy the design value. The operation modes of the hot water layer system and the other systems in the reactor pool, which had an effect on the formation of the hot water layer, were changed to reduce pool-top radiation level. After the above efforts, the temperature and the radioactivity distribution in the pool was measured to confirm whether this system blocked the rising coolant. The radiation level at the pool-top was significantly reduced below one tenth of that before installing the HWL and satisfied the design value. It was also confirmed by calculation that this hot water layer system would significantly reduce the release of fission gases to the reactor hall and the environment during the hypothetical accident as well. (author)

  13. Design of inventory pools in spare part support operation systems

    Science.gov (United States)

    Mo, Daniel Y.; Tseng, Mitchell M.; Cheung, Raymond K.

    2014-06-01

    The objective of a spare part support operation is to fulfill the part request order with different service contracts in the agreed response time. With this objective to achieve different service targets for multiple service contracts and the considerations of inventory investment, it is not only important to determine the inventory policy but also to design the structure of inventory pools and the order fulfilment strategies. In this research, we focused on two types of inventory pools: multiple inventory pool (MIP) and consolidated inventory pool (CIP). The idea of MIP is to maintain separated inventory pools based on the types of service contract, while CIP solely maintains a single inventory pool regardless of service contract. Our research aims to design the inventory pool analytically and propose reserve strategies to manage the order fulfilment risks in CIP. Mathematical models and simulation experiments would be applied for analysis and evaluation.

  14. Behavior of spent nuclear fuel in water pool storage

    International Nuclear Information System (INIS)

    Johnson, A.B. Jr.

    1977-09-01

    Storage of irradiated nuclear fuel in water pools (basins) has been standard practice since nuclear reactors first began operation approximately 34 years ago. Pool storage is the starting point for all other fuel storage candidate processes and is a candidate for extended interim fuel storage until policy questions regarding reprocessing and ultimate disposal have been resolved. This report assesses the current performance of nuclear fuel in pool storage, the range of storage conditions, and the prospects for extending residence times. The assessment is based on visits to five U.S. and Canadian fuel storage sites, representing nine storage pools, and on discussions with operators of an additional 21 storage pools. Spent fuel storage experience from British pools at Winfrith and Windscale and from a German pool at Karlsruhe (WAK) also is summarized

  15. Investigation of the condition of spent-fuel pool components

    International Nuclear Information System (INIS)

    Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

    1981-09-01

    It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts

  16. Decontamination of outdoor school swimming pools in Fukushima

    International Nuclear Information System (INIS)

    Saegusa, Jun

    2013-01-01

    After the Fukushima Daiichi NPP accident following the Great East Japan Earthquake, many school swimming pools in Fukushima have suspended water discharge, due to concerns that pool water which contains radioactive fallout is discharged into a river or waterway for agricultural use. The Japan Atomic Energy Agency conducted researches and examinations on the existing absorbent method and the flocculation method as ways for decontaminating pool water. By reviewing and improving these methods through decontamination demonstrations at eight pools in Fukushima, a practical decontamination method for outdoor pools has been established. This report summarizes the methods and results of the decontamination demonstrations carried out at the schools. Also, the surface density of fallout estimated at one of the pools is also presented and discussed in connection with the overall collection ratio of radiocesium at the pool. (author)

  17. Investigation of the condition of spent-fuel pool components

    Energy Technology Data Exchange (ETDEWEB)

    Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

    1981-09-01

    It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts.

  18. Expanding the live kidney donor pool: ethical considerations regarding altruistic donors, paired and pooled programs.

    Science.gov (United States)

    Patel, Shaneel Rajendra; Chadha, Priyanka; Papalois, Vassilios

    2011-06-01

    In renal transplant, there is a well-known deficiency in organ supply relative to demand. Live donation provides superior results when compared with deceased donation including a better rate of graft success and fewer immunologic complications. This deficiency in organs leads to significant morbidity and mortality rates. Alternative avenues have been extensively explored that may expand the live donor pool. They include altruistic donation as well as paired and pooled exchange programs. Altruistic donation is a truly selfless act from a donor unknown to the recipient. Kidney paired donation involves 2 incompatible donor-recipient pairs swapping donors to produce compatibility. Pooled donation involves at least 2 pairs, and can take the form of domino chains in which altruistic input sets up a chain of transplants, in which each recipient's incompatible donor makes a donation for the next recipient. Despite application of these various methods, there lie extensive ethical issues surrounding them. Misconceptions frequently occur; for instance, the perceived benefit that donating an organ to a loved one is greater for a related donor than for an altruistic one. Additionally, it is frequently believed that immunologic incompatibility offers coerced donors liberation from surgery, and that overcoming these barriers by introducing exchange programs provides vulnerable donors less protection. This article explores these and other complex ethical issues surrounding the various methods of expanding the donor pool. The authors offer opinions that challenge the ethical issues and attempt to overcome those views that hinder progress in the field.

  19. Technical specification for fabrication of HANARO pool cover

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Jeong Soo; Woo, Sang Ik

    2001-06-01

    This technical specification details the requirements and the acceptance criteria for design, seismic analysis, function test, installation and quality assurance for HANARO pool cover which will be installed at the top of reactor pool. The pool cover is classified as non-nuclear safety, seismic category II and quality class T. The basic design of the pool cover for increasing HANARO applications has been carried out for supporting the driving devices which can load, unload and rotate the irradiation targets in the in-core and out-core vertical irradiation holes under on-power operation. The comments of HANARO user group related with irradiation tests have optimally considered in the process of design. The interference between fuel handling and control absorber units in the reactor pool and activities to load, unload and rotate the irradiation targets at the top of the reactor pool have been minimized. The pool cover can be moved for maintenance and can protect the reactor pool from unexpected drop of foreign materials. It provides the space to vertical access of driving devices for NTD, CT/IR and OR4/OR5 under on-power operation. And the pool cover assembly must maintain its structural integrity under seismic load. Based on the above design concept, the HANARO pool cover has been proposed as supporting structure of driving devices for NTD, fission moly and RI production under on-power operation.

  20. Technical Facilities Management, Loan Pool, and Calibration

    Science.gov (United States)

    Smith, Jacob

    2011-01-01

    My work at JPL for the SURF program began on June 11, 2012 with the Technical Facilities Management group (TFM). As well as TFM, I worked with Loan Pool and Metrology to help them out with various tasks. Unlike a lot of other interns, I did not have a specific project rather many different tasks to be completed over the course of the 10 weeks.The first task to be completed was to sort through old certification reports in 6 different boxes to locate reports that needed to be archived into a digital database. There were no reports within these boxes that needed to be archived but rather were to be shredded. The reports went back to the early 1980's and up to the early 2000's. I was looking for reports dated from 2002 to 2012

  1. Soil carbon pools in different pasture systems

    Directory of Open Access Journals (Sweden)

    Francisco M. Cardozo, Jr.

    2016-03-01

    Full Text Available The aim of this study was to assess the carbon pools of a tropical soil where the native forest was replaced with different pasture systems. We studied five pasture production systems, including four monoculture systems with forage grasses such as Andropogon, Brachiaria, Panicum, and Cynodon, and an agroforestry system as well as a native vegetation plot. Greater availability of fulvic acid was detected in the agroforestry system as compared with that in the other systems. Higher lability of C was detected in the Andropogon system during the dry and rainy seasons and during the dry season in Cynodon. During the dry season, all pastures systems showed deficits in the net removal of atmospheric CO2. The structure and practices of the agroforestry system enables more carbon to be sequestered in the soil as compared with the monoculture pasture, suggesting that it is an important practice to mitigate climatic change and to improve soil quality.

  2. Corrosion surveillance in spent fuel storage pools

    International Nuclear Information System (INIS)

    Howell, J.P.

    1996-01-01

    In mid-1991, corrosion of aluminum-clad spent nuclear fuel was observed in the light-water filled basins at the Savannah River site. A corrosion surveillance program was initiated in the P, K, L-Reactor basins and in the Receiving Basin for Offsite Fuels (RBOF). This program verified the aggressive nature of the pitting corrosion and provided recommendations for changes in basin operations to permit extended longer term interim storage. The changes were implemented during 1994--1996 and have resulted in significantly improved basin water quality with conductivity in the 1--3 microS/cm range. Under these improved conditions, no new pitting has been observed over the last three years. This paper describes the corrosion surveillance program at SRS and what has been learned about the corrosion of aluminum-clad in spent fuel storage pools

  3. Drop Impact on to Moving Liquid Pools

    Science.gov (United States)

    Muñoz-Sánchez, Beatriz Natividad; Castrejón-Pita, José Rafael; Castrejón-Pita, Alfonso Arturo; Hutchings, Ian M.

    2014-11-01

    The deposition of droplets on to moving liquid substrates is an omnipresent situation both in nature and industry. A diverse spectrum of phenomena emerges from this simple process. In this work we present a parametric experimental study that discerns the dynamics of the impact in terms of the physical properties of the fluid and the relative velocity between the impacting drop and the moving liquid pool. The behaviour ranges from smooth coalescence (characterized by little mixing) to violent splashing (generation of multiple satellite droplets and interfacial vorticity). In addition, transitional regimes such as bouncing and surfing are also found. We classify the system dynamics and show a parametric diagram for the conditions of each regime. This work was supported by the EPSRC (Grant EP/H018913/1), the Royal Society, Becas Santander Universidades and the International Relationships Office of the University of Extremadura.

  4. One knowledge base or many knowledge pools?

    DEFF Research Database (Denmark)

    Lundvall, Bengt-Åke

    It is increasingly realized that knowledge is the most important resource and that learning is the most important process in the economy. Sometimes this is expressed by coining the current era as characterised by a ‘knowledge based economy'. But this concept might be misleading by indicating...... that there is one common knowledge base on which economic activities can be built. In this paper we argue that it is more appropriate to see the economy as connecting to different ‘pools of knowledge'. The argument is built upon a conceptual framework where we make distinctions between private/public, local....../global, individual/collective and tacit/codified knowledge. The purpose is both ‘academic' and practical. Our analysis demonstrates the limits of a narrowly economic perspective on knowledge and we show that these distinctions have important implications both for innovation policy and for management of innovation....

  5. Indoor swimming pools. Humidity caused problems and suggested solutions

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-01

    Reports have been received from across Canada on premature deterioration and other problems of indoor swimming pool buildings. This technical paper has been prepared to assist pool managers to solve these problems, which typically include leaking roofs, condensation on inside walls, peeling paint, efflorescence, rusting of metal elements, deterioration of concrete block structures, and high costs for pool heating. An effective insulation and vapor barrier system for a swimming pool roof is described, and the high relative humidity of the typical pool building is discussed as the primary cause of most problems. Proper sealing to cut down air infiltration is recommended, along with proper maintenance and painting. High energy costs are often due to low insulation values and to excessive ventilation used for decreasing the humidity. By using dehumidifiers capable of heat recovery, and by placing an insulating blanket on the pool after operating hours, it is shown that substantial cost savings are possible. 10 figs.

  6. Turbulence model for melt pool natural convection heat transfer

    International Nuclear Information System (INIS)

    Kelkar, K.M.; Patankar, S.V.

    1994-01-01

    Under severe reactor accident scenarios, pools of molten core material may form in the reactor core or in the hemispherically shaped lower plenum of the reactor vessel. Such molten pools are internally heated due to the radioactive decay heat that gives rise to buoyant flows in the molten pool. The flow in such pools is strongly influenced by the turbulent mixing because the expected Rayleigh numbers under accidents scenarios are very high. The variation of the local heat flux over the boundaries of the molten pools are important in determining the subsequent melt progression behavior. This study reports results of an ongoing effort towards providing a well validated mathematical model for the prediction of buoyant flow and heat transfer in internally heated pool under conditions expected in severe accident scenarios

  7. Sharing as risk pooling in a social dilemma experiment

    Directory of Open Access Journals (Sweden)

    Todd L. Cherry

    2015-03-01

    Full Text Available In rural economies with missing or incomplete markets, idiosyncratic risk is frequently pooled through informal networks. Idiosyncratic shocks, however, are not limited to private goods but can also restrict an individual from partaking in or benefiting from a collective activity. In these situations, a group must decide whether to provide insurance to the affected member. We describe results of a laboratory experiment designed to test whether a simple sharing institution can sustain risk pooling in a social dilemma with idiosyncratic risk. We tested whether risk could be pooled without a commitment device and, separately, whether effective risk pooling induced greater cooperation in the social dilemma. We found that even in the absence of a commitment device or reputational considerations, subjects voluntarily pooled risk, thereby reducing variance in individual earnings. In spite of effective risk pooling, however, cooperation in the social dilemma was unaffected.

  8. The burning and smoke release rates of sodium pool fires

    International Nuclear Information System (INIS)

    Newman, R.N.; Payne, J.F.B.

    1976-10-01

    The burning rates and smoke release fractions of sodium pool fires have been measured over the pool temperature range 250 0 C to 750 0 C. A theoretical model is derived which satisfactorily predicts the burning rate over the above temperature range. The theory further predicts that the burning rate should be independent of pool diameter, a prediction supported by a comparison of burning rate data from this study and available data from other studies. (author)

  9. Pool scrubbing and hydrodynamic experiments on jet injection regime

    International Nuclear Information System (INIS)

    Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez-Jimenez, J.

    1995-01-01

    Plant analyses have shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination ofboundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanisms acting at the pool entrance. As a consequence, a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei the pool were measured and fitted to a long normal distribution. Particularly, size was found to be quite sensitive to inletgas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major highlights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  10. Reserve growth in oil pools of Alberta : model and forecast

    Energy Technology Data Exchange (ETDEWEB)

    Verma, M.; Cook, T. [United States Geological Survey, Denver, CO (United States). Central Region

    2010-09-15

    This paper presented a reserve growth study that was conducted on oil pools in Alberta, Canada. Historical oil reserve data were evaluated to assess the potential for future reserve growth in both pools and fields, and reserve growth models and functions were developed to better forecast hydrocarbon volumes. The study also considered the sensitivity of reserve growth to such factors as pool size, porosity, and oil gravity. From 1960 to 2005, the reported known recoverable oil in Alberta, excluding the Athabasca oil sands and including only pools with adequate data, increased from 4.2 to 13.9 billion barrels of oil (BBO). New discoveries contributed 3.7 BBO and reserve growth added 6 BBO. Most reserve growth occurred in pools with more than 125,000 barrels of oil. Light-oil pools account for most of the total known oil volume and consequently showed the lowest growth. Pools with greater than 30 percent porosity grew more than pools with lower porosity reservoirs. Oil field growth was found to be almost twice that of pool growth, possibly because the analysis evaluated fields with two or more pools discovered in different years. The growth in oil volumes in Alberta pools is projected to be about 454 million barrels of oil in the period from 2006 to 2010. Over a 25-year period, the cumulative reserve growth in Alberta oil pools was substantially lower than other major petroleum-producing regions, but the growth at the field level compares well. 8 refs., 2 tabs., 9 figs.

  11. (Microbiological studies of small hot-bath-pools and hot-whirl-pools (author's transl))

    Energy Technology Data Exchange (ETDEWEB)

    Exner, M; Havenith, N

    1981-01-01

    Hot small bathing pools and hot whirl-pools have the following characteristics: small watervolume, thick squeeze of swimmers, high water temperature (37-40 degrees C) and small dimension of filters. By this, the quality of bathing-water is influenced detrimentally. To elaborate the hygienic problems, bathing-water samples were taken before, during and after the visiting-hours and were tested for facultative-pathogenic microorganisms. During this investigation E. coli was isolated in 25 degrees, Coliforms and Proteus species in 37.3%, P. aeruginosa in 36%, S. aureus in 26.3%, Enterococci in 42.3 %, Candida albicans in 3.6% and yeast totally in 8.3%.

  12. The atmospheric wet pool: definition and comparison with the oceanic warm pool

    Institute of Scientific and Technical Information of China (English)

    ZHANG Caiyun; CHEN Ge

    2008-01-01

    The oceanic warm pool (OWP) defined by sea surface temperature (SST) is known as the "heat reservoir" in the ocean. The warmest portion in the ocean mirrors the fact that the wettest region with the largest accumulation of water vapor (WV) in the atmosphere, termed atmospheric wet pool (AWP), should be identified because of the well-known Clausius-Clapeyron relationship between SST and WV. In this study, we used 14-year simultaneous observations of WV and SST from January 1988 to December 2001 to define the AWP and investigate its coupling and co-variations with the OWP. The joint examination of the area variations, centroid locations, and zonal migrations of the AWP and OWP lead to a number of interesting findings. The results hopefully can contribute to our understanding of the air-sea interaction in general and characterization of El Nifio/La Nina events in particular.

  13. Nuclear Insurance Pools: World-wide Practice and Prospective

    International Nuclear Information System (INIS)

    Reitsma, S. M. S.

    2000-01-01

    The following paper explains why Nuclear Insurance Pools were established, how they operate and what insurance protection they offer to the operations of nuclear installations. It will be shown that the clear interrelationship of the Pool-insurance operations, both on a national and an international level, has resulted in a transparency of each individual Pool-Member's exposure, which enables him to make the highest possible commitment to nuclear risks. Finally, some views will be given as regards the future prospective for the long proven method of pooling this particularly sensitive class of business. (author)

  14. A Double Evolutionary Pool Memetic Algorithm for Examination Timetabling Problems

    Directory of Open Access Journals (Sweden)

    Yu Lei

    2014-01-01

    Full Text Available A double evolutionary pool memetic algorithm is proposed to solve the examination timetabling problem. To improve the performance of the proposed algorithm, two evolutionary pools, that is, the main evolutionary pool and the secondary evolutionary pool, are employed. The genetic operators have been specially designed to fit the examination timetabling problem. A simplified version of the simulated annealing strategy is designed to speed the convergence of the algorithm. A clonal mechanism is introduced to preserve population diversity. Extensive experiments carried out on 12 benchmark examination timetabling instances show that the proposed algorithm is able to produce promising results for the uncapacitated examination timetabling problem.

  15. Crust formation and its effect on the molten pool coolability

    Energy Technology Data Exchange (ETDEWEB)

    Park, R.J.; Lee, S.J.; Sim, S.K. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-09-01

    Experimental and analytical studies of the crust formation and its effect on the molten pool coolability have been performed to examine the crust formation process as a function of boundary temperatures as well as to investigate heat transfer characteristics between molten pool and overlying water in order to evaluate coolability of the molten pool. The experimental test results have shown that the surface temperature of the bottom plate is a dominant parameter in the crust formation process of the molten pool. It is also found that the crust thickness of the case with direct coolant injection into the molten pool is greater than that of the case with a heat exchanger. Increasing mass flow rate of direct coolant injection to the molten pool does not affect the temperature of molten pool after the crust has been formed in the molten pool because the crust behaves as a thermal barrier. The Nusselt number between the molten pool and the coolant of the case with no crust formation is greater than that of the case with crust formation. The results of FLOW-3D analyses have shown that the temperature distribution contributes to the crust formation process due to Rayleigh-Benard natural convection flow.

  16. Automated management of engineering infrastructure of pools of different purpose

    Directory of Open Access Journals (Sweden)

    Shirokov Lev Alekseevich

    2016-10-01

    Full Text Available Pools play an important role in people’s life. They answer people’s demand in rest and improve their health. At the same time pools are rather important for industrial use, for example in construction industry. In order to solve different construction problems it is essential to investigate the influence of microclimatic parameters on construction materials and structures. For this aim pools are in demand as special test sites for construction materials and structures in different environmental conditions including the case of a direct water impact. The efficient use of pools presupposes the necessity of constant hydroclimatic contro: air humidity and temperature, water temperature, chemical composition of water and air. Classification of pools of different purposes is presented in the article. The author considers the main problems of operation of pools as objects with complicated air-and-water environment. The questions of maintaining optimal microclimatic parameters in a pool are considered. The necessity of use of the control system of a microclimate, its efficiency, profitability and social effect of its implementation is described. A mathematical model of the thermal mode of a pool area is constructed. The process of indoor temperature regulation in the pool is considered.

  17. Steam blowdown experiments with the condensation pool test rig

    International Nuclear Information System (INIS)

    Purhonen, H.; Puustinen, M.; Laine, J.; Raesaenen, A.; Kyrki-Rajamaeki, R.; Vihavainen, J.

    2005-01-01

    During a possible loss-of-coolant accident (Local) a large amount of non-condensable (nitrogen) and condensable (steam) gas is blown from the upper drywell of the containment to the condensation pool through the blowdown pipes at the boiling water reactors (BWRs). The wet well pool serves as the major heat sink for condensation of steam. The blowdown causes both dynamic and structural loads to the condensation pool. There might also be a risk that the gas discharging to the pool could push its way to the emergency core cooling systems (ECCS) and undermine their performance. (author)

  18. Evaporation-preventive device for nuclear reactor pool water

    International Nuclear Information System (INIS)

    Kurusu, Yoshihisa; Akabori, Shiro.

    1986-01-01

    Purpose: To prevent pool water from evaporating by a great amount in a reactor pool such as a spent fuel storing pool. Constitution: Air discharge and in-take ports are disposed just above the surface of the pool water and charge and discharge of airs are forcively carried out to form air curtains above the pool water. Water vapor evaporated from the surface of the pool water does not diffuse above the air curtains due to the air stream of the curtains, but is intaken into the intake port and then condensated into water by a steam condensator and re-supplied to the pool. Since diffusion of water vapor and radioactive materials are suppressed above the air curtains, the working circumstance in the pool chamber can be maintained desirably thereby keeping the radioactivity dose in the atmosphere. Further, incorporation of dusts from above into the pool can also be prevented by the air curtains to provide an effect for the prevention of radioactive contamination. Further, since covers are not used, visual observation can be insured. (Kawakami, Y.)

  19. Evaporation rate measurement in the pool of IEAR-1 reactor

    International Nuclear Information System (INIS)

    Torres, Walmir Maximo; Cegalla, Miriam A.; Baptista Filho, Benedito Dias

    2000-01-01

    The surface water evaporation in pool type reactors affects the ventilation system operation and the ambient conditions and dose rates in the operation room. This paper shows the results of evaporation rate experiment in the pool of IEA-R1 research reactor. The experiment is based on the demineralized water mass variation inside cylindrical metallic recipients during a time interval. Other parameters were measured, such as: barometric pressure, relative humidity, environmental temperature, water temperature inside the recipients and water temperature in the reactor pool. The pool level variation due to water contraction/expansion was calculated. (author)

  20. Livestock Grazing as a Driver of Vernal Pool Ecohydrology

    Science.gov (United States)

    Michaels, J.; McCarten, N. F.

    2017-12-01

    Vernal pools are seasonal wetlands that host rare plant communities of high conservation priority. Plant community composition is largely driven by pool hydroperiod. A previous study found that vernal pools grazed by livestock had longer hydroperiods compared with pools excluded from grazing for 10 years, and suggests that livestock grazing can be used to protect plant diversity. It is important to assess whether observed differences are due to the grazing or due to water balance variables including upland discharge into or out of the pools since no a priori measurements were made of the hydrology prior to grazing. To address this question, in 2016 we compared 15 pools that have been grazed continuously and 15 pools that have been fenced off for over 40 years at a site in Sacramento County. We paired pools based on abiotic characteristics (size, shape, slope, soil type) to minimize natural variation. We sampled vegetation and water depth using Solinst level loggers. We found that plant diversity and average hydroperiod was significantly higher in the grazed pools. We are currently measuring groundwater connectivity and upland inputs in order to compare the relative strength of livestock grazing as a driver of hydroperiod to these other drivers.

  1. Total quality in spent fuel pool reracking

    International Nuclear Information System (INIS)

    Cranston, J.S.; Bradbury, R.B.; Cacciapouti, R.J.

    1993-01-01

    The nuclear utility environment is one of strict cost control under prescriptive regulations and increasing public scrutiny. This paper presents the results of A Total Quality approach, by a dedicated team, that addresses the need for increased on-site spent fuel storage in this environment. Innovations to spent fuel pool reracking, driven by utilities' specific technical needs and shrinking budgets, have resulted in both product improvements and lower prices. A Total Quality approach to the entire turnkey project is taken, thereby creating synergism and process efficiency in each of the major phases of the project: design and analysis, licensing, fabrication, installation and disposal. Specific technical advances and the proven quality of the team members minimizes risk to the utility and its shareholders and provides a complete, cost effective service. Proper evaluation of spent fuel storage methods and vendors requires a full understanding of currently available customer driven initiatives that reduce cost while improving quality. In all phases of a spent fuel reracking project, from new rack design and analysis through old rack disposal, the integration of diverse experts, at all levels and throughout all phases of a reracking project, better serves utility needs. This Total Quality environment in conjunction with many technical improvements results in a higher quality product at a lower cost

  2. Positive year for Alberta power pool

    International Nuclear Information System (INIS)

    Reid-Carlson, D.

    1997-01-01

    The electricity power pool in Alberta completed its first year under deregulation. Results to date indicate that the competitive market has operated as intended. The effects of electricity pricing on the oil industry following deregulation were described, given the fact that electricity prices represent the second largest cost item to the oil industry after labour. The peculiarities of the mechanism of electricity pricing (based on hourly matching of supply offers to demand bids) were explained, highlighting the opportunities and risks to the oil industry caused by the hourly price variations and the difficulties involved in accurately forecasting on-peak and off-peak prices a full year in advance. In 1996 predicted average price was $14 to $17/MWh. The actual average price was $13.40/MWh. The general conclusion was that Alberta continues to have a surplus of electricity generation and is well positioned to to take advantage of its low generating costs, at least over the longer term. Short term bidding practices, however, may results in slightly higher system marginal prices

  3. Pool critical assembly pressure vessel facility benchmark

    International Nuclear Information System (INIS)

    Remec, I.; Kam, F.B.K.

    1997-07-01

    This pool critical assembly (PCA) pressure vessel wall facility benchmark (PCA benchmark) is described and analyzed in this report. Analysis of the PCA benchmark can be used for partial fulfillment of the requirements for the qualification of the methodology for pressure vessel neutron fluence calculations, as required by the US Nuclear Regulatory Commission regulatory guide DG-1053. Section 1 of this report describes the PCA benchmark and provides all data necessary for the benchmark analysis. The measured quantities, to be compared with the calculated values, are the equivalent fission fluxes. In Section 2 the analysis of the PCA benchmark is described. Calculations with the computer code DORT, based on the discrete-ordinates method, were performed for three ENDF/B-VI-based multigroup libraries: BUGLE-93, SAILOR-95, and BUGLE-96. An excellent agreement of the calculated (C) and measures (M) equivalent fission fluxes was obtained. The arithmetic average C/M for all the dosimeters (total of 31) was 0.93 ± 0.03 and 0.92 ± 0.03 for the SAILOR-95 and BUGLE-96 libraries, respectively. The average C/M ratio, obtained with the BUGLE-93 library, for the 28 measurements was 0.93 ± 0.03 (the neptunium measurements in the water and air regions were overpredicted and excluded from the average). No systematic decrease in the C/M ratios with increasing distance from the core was observed for any of the libraries used

  4. Iodine release from sodium pool combustion

    International Nuclear Information System (INIS)

    Sagawa, N.; Fukushima, Y.; Yokota, N.; Akagane, K.; Mochizuki, K.

    1979-01-01

    Iodine release associated with sodium pool combustion was determined by heating 20 gr sodium containing sodium iodide, which was labelled with 131 I and dissolved in the sodium in concentration of 1∼1,000 ppm, to burn on a nickel crucible in conditioned atmosphere in a closed vessel of 0.4 m 3 . Oxygen concentration was changed in 5∼21% and humidity in 0∼89% by mixing nitrogen gas and air. Combustion products were trapped by a Maypack filter composed of particle filters, copper screens and activated charcoal beds and by a glass beads pack cooled by liquid argon. Iodine collected on these filter elements was determined by radio-gas chromatography. When the sodium sample burned in the atmosphere of air at room temperature, the release fractions observed were 6∼33% for sodium and 1∼20% for iodine added in the sodium. The release iodine was present in aerosol at a ratio of 98%, and the remainder in the gas form. The release fraction of iodine trended to decrease as oxygen concentration and humidity in the atmosphere increased. No organic iodide was detected in the combustion products. (author)

  5. Swimming pools as heat sinks for air conditioners: Model design and experimental validation for natural thermal behavior of the pool

    Energy Technology Data Exchange (ETDEWEB)

    Woolley, Jonathan; Harrington, Curtis; Modera, Mark [University of California Davis, Western Cooling Efficiency Center, 1450 Drew Avenue, Suite 100, Davis, CA 95618 (United States)

    2011-01-15

    Swimming pools as thermal sinks for air conditioners could save approximately 40% on peak cooling power and 30% of overall cooling energy, compared to standard residential air conditioning. Heat dissipation from pools in semi-arid climates with large diurnal temperature shifts is such that pool heating and space cooling may occur concurrently; in which case heat rejected from cooling equipment could directly displace pool heating energy, while also improving space cooling efficiency. The performance of such a system relies on the natural temperature regulation of swimming pools governed by evaporative and convective heat exchange with the air, radiative heat exchange with the sky, and conductive heat exchange with the ground. This paper describes and validates a model that uses meteorological data to accurately predict the hourly temperature of a swimming pool to within 1.1 C maximum error over the period of observation. A thorough review of literature guided our choice of the most appropriate set of equations to describe the natural mass and energy exchange between a swimming pool and the environment. Monitoring of a pool in Davis, CA, was used to confirm the resulting simulations. Comparison of predicted and observed pool temperature for all hours over a 56 day experimental period shows an R-squared relatedness of 0.967. (author)

  6. Macroinvertebrate community assembly in pools created during peatland restoration.

    Science.gov (United States)

    Brown, Lee E; Ramchunder, Sorain J; Beadle, Jeannie M; Holden, Joseph

    2016-11-01

    Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

  7. The effect of environmental performance and preference disclosure on financial performance: Empirical evidence from unbalanced panel data of heavy-pollution industries in China

    Directory of Open Access Journals (Sweden)

    Kai Chang

    2015-01-01

    Full Text Available Purpose: Environmental performance and propensity disclosure is important for stakeholders to estimate firms’ incentives in environmental management practices. The purpose of this article is to explore the impacts of environmental performance and propensity disclosure on financial performance using unbalanced panel data of eight heavy-pollution industries in China. Design/methodology/approach: Environmental performance and propensity exhibits mutual causality relationship with Tobin’s Q value using unit root and co-integration test of panel data. Using panel data analysis, we take the impacts of environmental performance and propensity disclosure on financial performance from 2008 to 2012. Findings: Environmental performance has a significantly negative impact on Tobin’s Q value at the significance levels of 1%, while environmental propensity has a significantly positive effect on Tobin’s Q value at the significance levels of 5%. Firm size, financial leverage and return of assets have significantly positive impacts on financial performance at the significance levels of 1%. Meanwhile the effect of corporate environmental performance and propensity on financial performance has a significantly periodic difference from 2008 to 2012. Research limitations/implications: Those results are helpful for environmental regulators to evaluate the implementing effect of voluntary environmental policy and for firms’ managers to increase market expectation and improve financial performance. Originality/value: Environmental performance is estimated by 30 environmental indicators in eight heavy-pollution industries in China. Environmental performance and propensity disclosure has a U-typed relationship with financial performance.

  8. Quantitative Analysis of Adulterations in Oat Flour by FT-NIR Spectroscopy, Incomplete Unbalanced Randomized Block Design, and Partial Least Squares

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2014-01-01

    Full Text Available This paper developed a rapid and nondestructive method for quantitative analysis of a cheaper adulterant (wheat flour in oat flour by NIR spectroscopy and chemometrics. Reflectance FT-NIR spectra in the range of 4000 to 12000 cm−1 of 300 oat flour objects adulterated with wheat flour were measured. The doping levels of wheat flour ranged from 5% to 50% (w/w. To ensure the generalization performance of the method, both the oat and the wheat flour samples were collected from different producing areas and an incomplete unbalanced randomized block (IURB design was performed to include the significant variations that may be encountered in future samples. Partial least squares regression (PLSR was used to develop calibration models for predicting the levels of wheat flour. Different preprocessing methods including smoothing, taking second-order derivative (D2, and standard normal variate (SNV transformation were investigated to improve the model accuracy of PLS. The root mean squared error of Monte Carlo cross-validation (RMSEMCCV and root mean squared error of prediction (RMSEP were 1.921 and 1.975 (%, w/w by D2-PLS, respectively. The results indicate that NIR and chemometrics can provide a rapid method for quantitative analysis of wheat flour in oat flour.

  9. Effect of Si addition on the structure and corrosion behavior of NbN thin films deposited by unbalanced magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Velasco, L. [Universidad Nacional de Colombia, Departamento de Ingenieria Mecanica y Mecatronica, Facultad de Ingenieria, Bogota (Colombia); University of Southern California, Department of Chemical Engineering and Materials Science, Los Angeles, CA (United States); Olaya, J.J. [Universidad Nacional de Colombia, Departamento de Ingenieria Mecanica y Mecatronica, Facultad de Ingenieria, Bogota (Colombia); Rodil, S.E. [Universidad Nacional Autonoma de Mexico, Instituto de Investigaciones en Materiales, Mexico, D. F. (Mexico)

    2016-02-15

    In this work, nanostructured Nb{sub x}Si{sub y}N{sub z} thin films were deposited onto stainless steel AISI 304 substrates by co-sputtering a Nb target with Si additions while using unbalanced magnetron sputtering. The microstructure was analyzed by X-ray diffraction, and the chemical composition was identified by X-ray photoelectron spectroscopy. The hardness was measured by nanoindentation, and the corrosion resistance was studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy using a 3 wt% NaCl solution. The addition of Si in the NbN thin films changed the microstructure from a crystalline to an amorphous phase. The chemical analysis showed the presence of both Si{sub 3}N{sub 4} and NbN phases. The hardness decreased from 20 GPa (NbN) to 15 GPa for the film with the highest Si concentration (28.6 at.%). Nevertheless, the corrosion properties were significantly improved as the Si concentration increased; the polarization resistance after 168 h of immersion was two orders of magnitude larger in comparison with the substrate. (orig.)

  10. Syntheses and characterization of TiC/a:C composite coatings using pulsed closed field unbalanced magnetron sputtering (P-CFUBMS)

    International Nuclear Information System (INIS)

    Lin, J.; Moore, J.J.; Mishra, B.; Pinkas, M.; Sproul, W.D.

    2008-01-01

    TiC/a:C nanocomposite coatings were prepared by reactively sputtering titanium and graphite targets in pure argon atmosphere using a pulsed closed field unbalanced magnetron sputtering (P-CFUBMS) system. The microstructure of TiC/a:C coatings consisting of nanocrystalline TiC dispersed in an amorphous matrix of free carbon was investigated using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The effects of coating compositions on the structure and properties of TiC/a:C coatings were investigated. In the present study, TiC/a:C coatings exhibit high hardness (24-29 GPa), low coefficient of friction (0.24-0.25) and low wear rate (less than 2.5 x 10 -7 mm 3 N -1 m -1 ) when the carbon concentration is in the range of 55-66 at.%. Further increase of the carbon content beyond 70 at.% significantly decreased the volume fraction of TiC nanocrystalline and formed a large amount of free amorphous carbon in the coatings. The excessive amorphous carbon phases resulted in a decrease in the coating hardness and the sliding friction coefficient, e.g. a low COF of 0.15 was obtained when the carbon concentration reached 80.5 at.%. However, the decreased hardness will lead to an increase in the wear rate in these high carbon content TiC/a:C coatings

  11. Influence of substrate bias voltage on structure and properties of the CrAlN films deposited by unbalanced magnetron sputtering

    Science.gov (United States)

    Lv, Yanhong; Ji, Li; Liu, Xiaohong; Li, Hongxuan; Zhou, Huidi; Chen, Jianmin

    2012-02-01

    The CrAlN films were deposited on silicon and stainless steel substrates by unbalanced magnetron sputtering system. The influence of substrate bias on deposition rate, composition, structure, morphology and properties of the CrAlN films was investigated. The results showed that, with the increase of the substrate bias voltage, the deposition rate decreased accompanied by a change of the preferred orientation of the CrAlN film from (2 2 0) to (2 0 0). The grain size and the average surface roughness of the CrAlN films declined as the bias voltage increases above -100 V. The morphology of the films changed from obviously columnar to dense glass-like structure with the increase of the bias voltage from -50 to -250 V. Meanwhile, the films deposited at moderate bias voltage had better mechanical and tribological properties, while the films deposited at higher bias voltage showed better corrosion resistance. It was found that the corrosion resistance improvement was not only attributed to the low pinhole density of the film, but also to chemical composition of films.

  12. Structural and tribological properties of CrTiAlN coatings on Mg alloy by closed-field unbalanced magnetron sputtering ion plating

    International Nuclear Information System (INIS)

    Shi Yongjing; Long Siyuan; Yang Shicai; Pan Fusheng

    2008-01-01

    In this paper, a series of multi-layer hard coating system of CrTiAlN has been prepared by closed-field unbalanced magnetron sputtering ion plating (CFUBMSIP) technique in a gas mixture of Ar + N 2 . The coatings were deposited onto AZ31 Mg alloy substrates. During deposition step, technological temperature and metallic atom concentration of coatings were controlled by adjusting the currents of different metal magnetron targets. The nitrogen level was varied by using the feedback control of plasma optical emission monitor (OEM). The structural, mechanical and tribological properties of coatings were characterized by means of X-ray photoelectron spectrometry, high-resolution transmission electron microscope, field emission scanning electron microscope (FESEM), micro-hardness tester, and scratch and ball-on-disc tester. The experimental results show that the N atomic concentration increases and the oxide on the top of coatings decreases; furthermore the modulation period and the friction coefficient decrease with the N 2 level increasing. The outstanding mechanical property can be acquired at medium N 2 level, and the CrTiAlN coatings on AZ31 Mg alloy substrates outperform the uncoated M42 high speed steel (HSS) and the uncoated 316 stainless steel (SS)

  13. Improving optical properties of silicon nitride films to be applied in the middle infrared optics by a combined high-power impulse/unbalanced magnetron sputtering deposition technique.

    Science.gov (United States)

    Liao, Bo-Huei; Hsiao, Chien-Nan

    2014-02-01

    Silicon nitride films are prepared by a combined high-power impulse/unbalanced magnetron sputtering (HIPIMS/UBMS) deposition technique. Different unbalance coefficients and pulse on/off ratios are applied to improve the optical properties of the silicon nitride films. The refractive indices of the Si3N4 films vary from 2.17 to 2.02 in the wavelength ranges of 400-700 nm, and all the extinction coefficients are smaller than 1×10(-4). The Fourier transform infrared spectroscopy and x-ray diffractometry measurements reveal the amorphous structure of the Si3N4 films with extremely low hydrogen content and very low absorption between the near IR and middle IR ranges. Compared to other deposition techniques, Si3N4 films deposited by the combined HIPIMS/UBMS deposition technique possess the highest refractive index, the lowest extinction coefficient, and excellent structural properties. Finally a four-layer coating is deposited on both sides of a silicon substrate. The average transmittance from 3200 to 4800 nm is 99.0%, and the highest transmittance is 99.97% around 4200 nm.

  14. The Study of Deposition Parameters, Properties for PVD TixN and CrxN Coatings Using a Closed Field Unbalanced Magnetron Sputter Ion Plating System

    Institute of Scientific and Technical Information of China (English)

    Hailin Sun; Susan Field; Jian Chen; Dennis. G. Teer

    2004-01-01

    Closed Field Unbalanced Magnetron Sputter Ion Plating (CFUBMSIP) systems have been used increasingly for PVD coating in recent years. TiN and CrN coatings, commonly used as the basic coating for a number of different hard coatings, have been chosen to study the coating process parameters for the CFUBMSIP system. In this paper, the process parameters, such as substrate temperature, substrate bias and OEM control, have been carefully examined to achieve hard and wear-resistance coatings with good adhesion. The coating structure and orientation were found to change according to the coating parameters. The Rockwell test and Scratch test were carried out to examine the coating adhesion; pin-on-disc testing was used to estimate the wear-resistant; micro-hardness was also used to determine coating hardness. HSS drill testing has been carried out to study the general properties of the coating for cutting tool application. A combination of process parameters can be selected to achieve good performance for the TiN and CrN coatings.

  15. Structural, chemical and nanomechanical investigations of SiC/polymeric a-C:H films deposited by reactive RF unbalanced magnetron sputtering

    Science.gov (United States)

    Tomastik, C.; Lackner, J. M.; Pauschitz, A.; Roy, M.

    2016-03-01

    Amorphous carbon (or diamond-like carbon, DLC) films have shown a number of important properties usable for a wide range of applications for very thin coatings with low friction and good wear resistance. DLC films alloyed with (semi-)metals show some improved properties and can be deposited by various methods. Among those, the widely used magnetron sputtering of carbon targets is known to increase the number of defects in the films. Therefore, in this paper an alternative approach of depositing silicon-carbide-containing polymeric hydrogenated DLC films using unbalanced magnetron sputtering was investigated. The influence of the C2H2 precursor concentration in the deposition chamber on the chemical and structural properties of the deposited films was investigated by Raman spectroscopy, X-ray photoelectron spectroscopy and elastic recoil detection analysis. Roughness, mechanical properties and scratch response of the films were evaluated with the help of atomic force microscopy and nanoindentation. The Raman spectra revealed a strong correlation of the film structure with the C2H2 concentration during deposition. A higher C2H2 flow rate results in an increase in SiC content and decrease in hydrogen content in the film. This in turn increases hardness and elastic modulus and decreases the ratio H/E and H3/E2. The highest scratch resistance is exhibited by the film with the highest hardness, and the film having the highest overall sp3 bond content shows the highest elastic recovery during scratching.

  16. Effect of Si addition on the structure and corrosion behavior of NbN thin films deposited by unbalanced magnetron sputtering

    International Nuclear Information System (INIS)

    Velasco, L.; Olaya, J.J.; Rodil, S.E.

    2016-01-01

    In this work, nanostructured Nb x Si y N z thin films were deposited onto stainless steel AISI 304 substrates by co-sputtering a Nb target with Si additions while using unbalanced magnetron sputtering. The microstructure was analyzed by X-ray diffraction, and the chemical composition was identified by X-ray photoelectron spectroscopy. The hardness was measured by nanoindentation, and the corrosion resistance was studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy using a 3 wt% NaCl solution. The addition of Si in the NbN thin films changed the microstructure from a crystalline to an amorphous phase. The chemical analysis showed the presence of both Si 3 N 4 and NbN phases. The hardness decreased from 20 GPa (NbN) to 15 GPa for the film with the highest Si concentration (28.6 at.%). Nevertheless, the corrosion properties were significantly improved as the Si concentration increased; the polarization resistance after 168 h of immersion was two orders of magnitude larger in comparison with the substrate. (orig.)

  17. Prader-Willi Syndrome due to an Unbalanced de novo Translocation t(15;19)(q12;p13.3).

    Science.gov (United States)

    Dang, Vy; Surampalli, Abhilasha; Manzardo, Ann M; Youn, Stephanie; Butler, Merlin G; Gold, June-Anne; Kimonis, Virginia E

    2016-01-01

    Prader-Willi syndrome (PWS) is a complex, multisystem genetic disorder characterized by endocrine, neurologic, and behavioral abnormalities. We report the first case of an unbalanced de novo reciprocal translocation of chromosomes 15 and 19, 45,XY,-15,der(19)t(15;19)(q12;p13.3), resulting in monosomy for the PWS critical chromosome region. Our patient had several typical features of PWS including infantile hypotonia, a poor suck and feeding difficulties, tantrums, skin picking, compulsions, small hands and feet, and food seeking, but not hypopigmentation, a micropenis, cryptorchidism or obesity as common findings seen in PWS at the time of examination at 6 years of age. He had seizures noted from 1 to 3 years of age and marked cognitive delay. High-resolution SNP microarray analysis identified an atypical PWS type I deletion in chromosome 15 involving the proximal breakpoint BP1. The deletion extended beyond the GABRB3 gene but was proximal to the usual distal breakpoint (BP3) within the 15q11q13 region, and GABRA5, GABRG3, and OCA2 genes were intact. No deletion of band 19p13.3 was detected; therefore, the patient was not at an increased risk of tumors from the Peutz-Jeghers syndrome associated with a deletion of the STK11 gene. © 2016 S. Karger AG, Basel.

  18. 76 FR 72923 - Pool Corporation; Analysis To Aid Public Comment

    Science.gov (United States)

    2011-11-28

    ... manufacturers, warehouse them, and then resell the products to pool retail stores, pool service companies and.... ADDRESSES: Interested parties may file a comment online or on paper, by following the instructions in the... 0115'' on your comment, and file your comment online at https://ftcpublic.commentworks.com/ftc...

  19. Solar collectors for swimming pools still going strong

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    According to the opinion of the experts, solar energy heating may be technically 'mature' but the profitability is by no means that far. However, solar systems are a good alternative for heating the water in swimming pools. Four solar collector systems developed by different firms to heat swimming pools, including prices, are presented.

  20. Microscopic bubble behaviour in suppression pool during wetwell venting

    Science.gov (United States)

    Zablackaite, G.; Nagasaka, H.; Kikura, H.

    2017-10-01

    During a severe accident PCV failure should be avoided and fission products inside PCV should be confined as much as possible. In order to minimize FPs release, Wetwell venting is conducted by releasing steam-non-condensable gas mixture carrying FPs from the Drywell to Suppression Pool. Steam is condensed by subcooled water in the pool, and most of FPs are retained into water. The removal of FP in the water pool is referred to as “Pool Scrubbing effect”. Hydrodynamic parameters of bubbles have impact on pool scrubbing effect. However, there is only few data available to evaluate quantitatively the bubble behaviour under depressurization and/or thermal stratification conditions. Series of experiments were conducted to evaluate the influence of temperature distribution, non-condensable gas content and pressure in the Wetwell on bubble behaviour. Bubbles were visualized using High Speed Camera and adopting shadowgraphy technique. Applying Particle Tracking Velocimetry, bubble velocity and size distribution were obtained from recorded images. Experimental results show that with increasing suppression pool temperature, bubbles reaching the pool surface decreased in size and traveling velocity became slower. In pressurized wetwell, bubble behaviour was similar to that in the heated up suppression pool case, although bubble parameters were similar to the low temperature case. Higher air content induced water surface movement and bubbles were smaller due to break up.

  1. 48 CFR 28.304 - Risk-pooling arrangements.

    Science.gov (United States)

    2010-10-01

    ... CONTRACTING REQUIREMENTS BONDS AND INSURANCE Insurance 28.304 Risk-pooling arrangements. Agencies may establish risk-pooling arrangements. These arrangements are designed to use the services of the insurance industry for safety engineering and the handling of claims at minimum cost to the Government. The agency...

  2. Biomass and carbon pools of disturbed riparian forests

    Science.gov (United States)

    Laura A. B. Giese; W. M. Aust; Randall K. Kolka; Carl C. Trettin

    2003-01-01

    Quantification of carbon pools as affected by forest age/development can facilitate riparian restoration and increase awareness of the potential for forests to sequester global carbon. Riparian forest biomass and carbon pools were quantified for four riparian forests representing different seral stages in the South Carolina Upper Coastal Plain. Three of the riparian...

  3. 17 CFR 275.206(4)-8 - Pooled investment vehicles.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Pooled investment vehicles... COMMISSION (CONTINUED) RULES AND REGULATIONS, INVESTMENT ADVISERS ACT OF 1940 § 275.206(4)-8 Pooled investment vehicles. (a) Prohibition. It shall constitute a fraudulent, deceptive, or manipulative act...

  4. Mathematical-programming approaches to test item pool design

    NARCIS (Netherlands)

    Veldkamp, Bernard P.; van der Linden, Willem J.; Ariel, A.

    2002-01-01

    This paper presents an approach to item pool design that has the potential to improve on the quality of current item pools in educational and psychological testing andhence to increase both measurement precision and validity. The approach consists of the application of mathematical programming

  5. Anticipated corrosion in the Vermont Yankee spent fuel pool

    International Nuclear Information System (INIS)

    Weeks, J.R.

    1977-06-01

    The report provides additional information relating to a proposed modification to the spent fuel pool at the Vermont Yankee Nuclear Power Station (VYNPS) and addresses corrosion of spent fuel pool storage materials and zircaloy, and provides an analysis of the effectiveness of the Boral sealing

  6. Numerical analysis of weld pool oscillation in laser welding

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jung Ho [Chungbuk National University, Cheongju (Korea, Republic of); Farson, Dave F [The Ohio State University, Columbus (United States); Hollis, Kendall; Milewski, John O. [Los Alamos National Laboratory, Los Alamos (United States)

    2015-04-15

    Volume of fluid (VOF) numerical simulation was used to investigate melt flow and volumetric oscillation of conduction-mode pulsed laser weld pools. The result is compared to high speed video stream of titanium laser spot welding experiment. The total simulation time is 10ms with the first 5 ms being heating and melting under constant laser irradiation and the remaining 5 ms corresponding to resolidification of the weld pool. During the melting process, the liquid pool did not exhibit periodic oscillation but was continually depressed by the evaporation recoil pressure. After the laser pulse, the weld pool was excited into volumetric oscillation by the release of pressure on its surface and oscillation of the weld pool surface was analyzed. The simulation model suggested adjusting thermal diffusivity to match cooling rate and puddle diameter during solidification which is distinguishable from previous weld pool simulation. The frequency continuously increased from several thousand cycles per second to tens of thousands of cycles per second as the weld pool solidified and its diameter decreased. The result is the first trial of investigation of small weld pool oscillation in laser welding although there have been several reports about arc welding.

  7. 13 CFR 120.1709 - Transfers of Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Transfers of Pool Certificates. 120.1709 Section 120.1709 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1709...

  8. 13 CFR 120.1714 - Seller's Pool Loan servicing.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan servicing. 120.1714 Section 120.1714 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1714 Seller...

  9. 13 CFR 120.1715 - Seller's Pool Loan liquidation.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan liquidation. 120.1715 Section 120.1715 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1715 Seller...

  10. 13 CFR 120.1713 - Seller's Pool Loan origination.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan origination. 120.1713 Section 120.1713 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1713 Seller...

  11. 13 CFR 120.1717 - Seller's Pool Loan deferments.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Seller's Pool Loan deferments. 120.1717 Section 120.1717 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Establishment of SBA Secondary Market Guarantee Program for First Lien Position 504 Loan Pools § 120.1717 Seller...

  12. AUS burnup module CHAR and the associated data pool

    International Nuclear Information System (INIS)

    Robinson, G.S.

    1975-12-01

    The CHAR module of the AUS reactor neutronics scheme solves the multiregion nuclide depletion equations using an analytic method. The module obtains cross section, flux and geometry data from AUS data pools, and uses the STATUS data pool which has been designed for the storage of nuclide compositions, spatial smearing factors and other miscellaneous information. (author)

  13. Phytomass carbon pool of trees and forests in India

    NARCIS (Netherlands)

    Kaul, M.; Mohren, G.M.J.; Dadhwal, V.K.

    2011-01-01

    The study reports estimates of above ground phytomass carbon pools in Indian forests for 1992 and 2002 using two different methodologies. The first estimate was derived from remote sensing based forest area and crown density estimates, and growing stock data for 1992 and 2002 and the estimated pool

  14. Odonata (Insecta at a wadi Pool near Nizwa, northern Oman

    Directory of Open Access Journals (Sweden)

    Elaine M. Cowan

    2015-07-01

    Full Text Available Fourteen damselfly and dragonfly species were recorded in 68 visits to a wadi pool in northern Oman, March 2012 to June 2014.  All identifications were based on photographs.  Apparently the pool has a core community of eight resident species.  Paragomphus sinaiticus, globally Near Threatened, was regularly  recorded. 

  15. Electricity prices and generator behaviour in gross pool electricity markets

    International Nuclear Information System (INIS)

    O'Mahoney, Amy; Denny, Eleanor

    2013-01-01

    Electricity market liberalisation has become common practice internationally. The justification for this process has been to enhance competition in a market traditionally characterised by statutory monopolies in an attempt to reduce costs to end-users. This paper endeavours to see whether a pool market achieves this goal of increasing competition and reducing electricity prices. Here the electricity market is set up as a sealed bid second price auction. Theory predicts that such markets should result with firms bidding their marginal cost, thereby resulting in an efficient outcome and lower costs to consumers. The Irish electricity system with a gross pool market experiences among the highest electricity prices in Europe. Thus, we analyse the Irish pool system econometrically in order to test if the high electricity prices seen there are due to participants bidding outside of market rules or out of line with theory. Overall we do not find any evidence that the interaction between generator and the pool in the Irish electricity market is not efficient. Thus, the pool element of the market structure does not explain the high electricity prices experienced in Ireland. - Highlights: • We consider whether a gross pool achieves competitive behaviour. • We analyse the Irish pool system econometrically. • Results indicate the Irish pool system appears to work efficiently. • Generators appear to be bidding appropriately

  16. Branchipodopsis species — specialists of ephemeral rock pools ...

    African Journals Online (AJOL)

    Such rock pools were studied in the Drakensberg region, in the eastern Free State and in south-eastern Botswana. Common features ... While short-range dispersal of floating eggs by overflows is common, long-range dispersal (e.g. by wind) seems to be rare and to be restricted to shallow pools with little vegetation. Limited ...

  17. Characteristics of fission product release from a molten pool

    International Nuclear Information System (INIS)

    Yun, J.I.; Suh, K.Y.; Kang, C.S.

    2001-01-01

    The volatile fission products are released from the debris pool, while the less volatile fission products tend to remain as condensed phases because of their low vapor pressure. The release of noble gases and the volatile fission products is dominated by bubble dynamics. The release of the less volatile fission products from the pool can be analyzed based on mass transport through a liquid with the convection flow. The physico-numerical models were orchestrated from existing submodels in various disciplines of engineering to estimate the released fraction of fission products from a molten pool. It was assumed that the pool has partially filled hemispherical geometry. For the high pool pressure, the diameter of the bubbles at detachment was calculated utilizing the Cole and Shulman correlation with the effect of system pressure. Sensitivity analyses were performed and results of the numerical calculations were compared with analysis results for the TMI-2 accident. (author)

  18. Tax credits and purchasing pools: will this marriage work?

    Science.gov (United States)

    Trude, S; Ginsburg, P B

    2001-04-01

    Bipartisan interest is growing in Congress for using federal tax credits to help low-income families buy health insurance. Regardless of the approach taken, tax credit policies must address risk selection issues to ensure coverage for the chronically ill. Proposals that link tax credits to purchasing pools would avoid risk selection by grouping risks similar to the way large employers do. Voluntary purchasing pools have had only limited success, however. This Issue Brief discusses linking tax credits to purchasing pools. It uses information from the Center for Studying Health System Change's (HSC) site visits to 12 communities as well as other research to assess the role of purchasing pools nationwide and the key issues and implications of linking tax credits and pools.

  19. Controlling pool depth during VAR of Alloy 718

    Science.gov (United States)

    Lopez, F.; Beaman, J.; Williamson, R.; Evans, D.

    2016-07-01

    A longtime goal of superalloy producers has been to control the geometry of the liquid pool in solidifying ingots. Accurate pool depth control at appropriate values is expected to result in ingots free of segregation defects. This article describes an industrial VAR experiment in which a 430mm (17 in) diameter Alloy 718 electrode was melted into a 510mm (20 in) ingot. In the experiment, the depth of the liquid pool at the mid-radius was controlled to three different set-points: 137 mm (nominal), 193 mm (deep) and 118 mm (shallow). At each level, the pool depth was marked by a power cutback of several minutes. The ingot was sectioned and longitudinal slices were cut out. Analysis of the photographed ingot revealed that accurate control was obtained for both the nominal and deep pool cases, while the third one was not conclusive.

  20. Parametric tomography of the cardiac blood pool

    International Nuclear Information System (INIS)

    Meyer, M.; Schwartz, K.D.

    1990-01-01

    In nuclear cardiology image processing is performed usually in 3 of 4 dimensions. ECG-gated SPECT (GSPECT) would make it possible to obtain all 4 dimensions of space and time during one examination, but its duration as well as radiation dose is limited resulting in a low signal-to-noise ratio. Sensitive feature extractions from the amount of data are necessary, e.g. Fourier filtering or extracting isovolumetric intervals. The relatively large amount of calculations and storage requirements often handicaps tomographic ventriculography because a high number of sections have to be processed and the temporal resolution is limited. A new list-mode oriented tomographic algorithm demands less storage and fewer calculations: The Fourier coefficient extraction and the filtered back projection, both of which are linear operations, could be interchanged in the case of thoracic SPECT. The feature extraction algorithm process internal list-mode heart cycles for discrimination of invalid cycles, for end-diastolic and end-systolic synthesis as well as for Fourier analysis of the first harmonic in 10 ms steps. Reconstruction operations are applied also to modified distribution matrices of Fourier coefficients. By only processing 4 spatial matrix sequences (end-diastolic and end-systolic images, amplitude and phase values) parametric tomography becomes practicable and could be also performed by a minicomputer with 64 KByte memory in addition to the possibilities of the planar left ventricular gated imaging. If there are 3 or more processors available a complete feature extraction on-the-fly will be possible. The numerical algorithms were tested with respect to stable reconstructions by phantoms. First results of a patient examination are used to explore effective display techniques, and preliminary modes are demonstrated. It is the purpose of this study to obtain additional information about the gated planar cardiac blood pool imaging in the field of SPECT. (author)

  1. poolHiTS: A Shifted Transversal Design based pooling strategy for high-throughput drug screening

    Directory of Open Access Journals (Sweden)

    Woolf Peter J

    2008-05-01

    Full Text Available Abstract Background A key goal of drug discovery is to increase the throughput of small molecule screens without sacrificing screening accuracy. High-throughput screening (HTS in drug discovery involves testing a large number of compounds in a biological assay to identify active compounds. Normally, molecules from a large compound library are tested individually to identify the activity of each molecule. Usually a small number of compounds are found to be active, however the presence of false positive and negative testing errors suggests that this one-drug one-assay screening strategy can be significantly improved. Pooling designs are testing schemes that test mixtures of compounds in each assay, thereby generating a screen of the whole compound library in fewer tests. By repeatedly testing compounds in different combinations, pooling designs also allow for error-correction. These pooled designs, for specific experiment parameters, can be simply and efficiently created using the Shifted Transversal Design (STD pooling algorithm. However, drug screening contains a number of key constraints that require specific modifications if this pooling approach is to be useful for practical screen designs. Results In this paper, we introduce a pooling strategy called poolHiTS (Pooled High-Throughput Screening which is based on the STD algorithm. In poolHiTS, we implement a limit on the number of compounds that can be mixed in a single assay. In addition, we show that the STD-based pooling strategy is limited in the error-correction that it can achieve. Due to the mixing constraint, we show that it is more efficient to split a large library into smaller blocks of compounds, which are then tested using an optimized strategy repeated for each block. We package the optimal block selection algorithm into poolHiTS. The MATLAB codes for the poolHiTS algorithm and the corresponding decoding strategy are also provided. Conclusion We have produced a practical version

  2. A Mechanistic Model of Waterfall Plunge Pool Erosion into Bedrock

    Science.gov (United States)

    Scheingross, Joel S.; Lamb, Michael P.

    2017-11-01

    Landscapes often respond to changes in climate and tectonics through the formation and upstream propagation of knickzones composed of waterfalls. Little work has been done on the mechanics of waterfall erosion, and instead most landscape-scale models neglect waterfalls or use rules for river erosion, such as stream power, that may not be applicable to waterfalls. Here we develop a physically based model to predict waterfall plunge pool erosion into rock by abrasion from particle impacts and test the model against flume experiments. Both the model and experiments show that evolving plunge pools have initially high vertical erosion rates due to energetic particle impacts, and erosion slows and eventually ceases as pools deepen and deposition protects the pool floor from further erosion. Lateral erosion can continue after deposition on the pool floor, but it occurs at slow rates that become negligible as pools widen. Our work points to the importance of vertical drilling of successive plunge pools to drive upstream knickzone propagation in homogenous rock, rather than the classic mechanism of headwall undercutting. For a series of vertically drilling waterfalls, we find that upstream knickzone propagation is faster under higher combined water and sediment fluxes and for knickzones composed of many waterfalls that are closely spaced. Our model differs significantly from stream-power-based erosion rules in that steeper knickzones can retreat faster or more slowly depending on the number and spacing of waterfalls within a knickzone, which has implications for interpreting climatic and tectonic history through analysis of river longitudinal profiles.

  3. Addressing data privacy in matched studies via virtual pooling.

    Science.gov (United States)

    Saha-Chaudhuri, P; Weinberg, C R

    2017-09-07

    Data confidentiality and shared use of research data are two desirable but sometimes conflicting goals in research with multi-center studies and distributed data. While ideal for straightforward analysis, confidentiality restrictions forbid creation of a single dataset that includes covariate information of all participants. Current approaches such as aggregate data sharing, distributed regression, meta-analysis and score-based methods can have important limitations. We propose a novel application of an existing epidemiologic tool, specimen pooling, to enable confidentiality-preserving analysis of data arising from a matched case-control, multi-center design. Instead of pooling specimens prior to assay, we apply the methodology to virtually pool (aggregate) covariates within nodes. Such virtual pooling retains most of the information used in an analysis with individual data and since individual participant data is not shared externally, within-node virtual pooling preserves data confidentiality. We show that aggregated covariate levels can be used in a conditional logistic regression model to estimate individual-level odds ratios of interest. The parameter estimates from the standard conditional logistic regression are compared to the estimates based on a conditional logistic regression model with aggregated data. The parameter estimates are shown to be similar to those without pooling and to have comparable standard errors and confidence interval coverage. Virtual data pooling can be used to maintain confidentiality of data from multi-center study and can be particularly useful in research with large-scale distributed data.

  4. Preliminary Calculation on a Spent Fuel Pool Accident using GOTHIC

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaehwan; Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek [KHNP-CRI, Daejeon (Korea, Republic of)

    2015-10-15

    The probability of an accident happening at the spent fuel pool was believed to be quite low until the 2011 Fukushima accident occurred. Notably, large amount of spent fuel are normally stored in the spent fuel pool for a long time compared to the amount of fuel in the reactor core and the total heat released from the spent fuel is high enough to boil the water of the spent fuel pool when the cooling system does not operate. In addition, the enrichment and the burnup of the fuel have both increased in the past decade and heat generation from the spent fuel thereby has also increased. The failure of the cooling system at the spent fuel pool (hereafter, a loss-of-cooling accident) is one of the principal hypothetical causes of an accident that could occur at the spent fuel pool. In this paper, the preliminary calculation of a loss-of-cooling accident was performed. In this paper, the preliminary calculation of a loss-of cooling accident was performed with GOTHIC. The calculation results show boiling away of water in the spent fuel pool due to the loss-of-cooling accident and similar thermal performance of the spent fuel pool with previous research results.

  5. 3D finite element simulation of TIG weld pool

    Science.gov (United States)

    Kong, X.; Asserin, O.; Gounand, S.; Gilles, P.; Bergheau, J. M.; Medale, M.

    2012-07-01

    The aim of this paper is to propose a three-dimensional weld pool model for the moving gas tungsten arc welding (GTAW) process, in order to understand the main factors that limit the weld quality and improve the productivity, especially with respect to the welding speed. Simulation is a very powerful tool to help in understanding the physical phenomena in the weld process. A 3D finite element model of heat and fluid flow in weld pool considering free surface of the pool and traveling speed has been developed for the GTAW process. Cast3M software is used to compute all the governing equations. The free surface of the weld pool is calculated by minimizing the total surface energy. The combined effects of surface tension gradient, buoyancy force, arc pressure, arc drag force to drive the fluid flow is included in our model. The deformation of the weld pool surface and the welding speed affect fluid flow, heat flow and thus temperature gradients and molten pool dimensions. Welding trials study is presented to compare our numerical results with macrograph of the molten pool.

  6. Study on water evaporation rate from indoor swimming pools

    Directory of Open Access Journals (Sweden)

    Rzeźnik Ilona

    2017-01-01

    Full Text Available The air relative humidity in closed spaces of indoor swimming pools influences significantly on users thermal comfort and the stability of the building structure, so its preservation on suitable level is very important. For this purpose, buildings are equipped with HVAC systems which provide adequate level of humidity. The selection of devices and their technical parameters is made using the mathematical models of water evaporation rate in the unoccupied and occupied indoor swimming pool. In the literature, there are many papers describing this phenomena but the results differ from each other. The aim of the study was the experimental verification of published models of evaporation rate in the pool. The tests carried out on a laboratory scale, using model of indoor swimming pool, measuring 99cm/68cm/22cm. The model was equipped with water spray installation with six nozzles to simulate conditions during the use of the swimming pool. The measurements were made for conditions of sports pools (water temperature 24°C and recreational swimming pool (water temperature 34°C. According to the recommendations the air temperature was about 2°C higher than water temperature, and the relative humidity ranged from 40% to 55%. Models Shah and Biasin & Krumm were characterized by the best fit to the results of measurements on a laboratory scale.

  7. Security cost allocation under combined bilateral-pool market dispatch

    International Nuclear Information System (INIS)

    Abdullah, M.P.; Hassan, M.Y.; Hussin, F.

    2008-01-01

    Most electricity markets around the world are a combination of bilateral and pool markets, such as NordPool and NYPOOL. In these models, market participants bid into the pool and also make bilateral contracts with each other. This paper addressed the issue of congestion management and security cost allocation in a power pool market model. The basic idea of security cost allocation is to divide the incurred security cost due to congestion relief into pool and bilateral market based on their flow contribution to the congested line. A newly proposed security cost allocation strategy of the combined bilateral-pool market was also presented along with case studies using IEEE-14 bus system that tested the proposed method. Using the proposed method, it was shown that security costs are allocated to market participants at different prices which reflect the load contribution to the security problem. This solves the problem of the uniform security cost allocation in a pure pool market system having uniform pricing, and provides a proper security signal to market participants. 11 refs., 3 tabs., 4 figs

  8. Loss of spent fuel pool cooling PRA: Model and results

    International Nuclear Information System (INIS)

    Siu, N.; Khericha, S.; Conroy, S.; Beck, S.; Blackman, H.

    1996-09-01

    This letter report documents models for quantifying the likelihood of loss of spent fuel pool cooling; models for identifying post-boiling scenarios that lead to core damage; qualitative and quantitative results generated for a selected plant that account for plant design and operational practices; a comparison of these results and those generated from earlier studies; and a review of available data on spent fuel pool accidents. The results of this study show that for a representative two-unit boiling water reactor, the annual probability of spent fuel pool boiling is 5 x 10 -5 and the annual probability of flooding associated with loss of spent fuel pool cooling scenarios is 1 x 10 -3 . Qualitative arguments are provided to show that the likelihood of core damage due to spent fuel pool boiling accidents is low for most US commercial nuclear power plants. It is also shown that, depending on the design characteristics of a given plant, the likelihood of either: (a) core damage due to spent fuel pool-associated flooding, or (b) spent fuel damage due to pool dryout, may not be negligible

  9. Study on velocity distribution in a pool by submersible mixers

    International Nuclear Information System (INIS)

    Tian, F; Shi, W D; Lu, X N; Chen, B; Jiang, H

    2012-01-01

    To study the distribution of submersible mixers and agitating effect in the sewage treatment pool, Pro/E software was utilized to build the three-dimensional model. Then, the large-scale computational fluid dynamics software FLUENT6.3 was used. ICEM software was used to build unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. The macro fluid field and each section velocity flow field distribution were analyzed to observe the efficiency of each submersible mixer. The average velocity and mixing area in the sewage pool were studied simultaneously. Results show that: the preferred project B, two submersible mixers speed is 980 r/min, and setting angles are all 30°. Fluid mixing area in the pool has reached more than 95%. Under the action of two mixers, the fluid in the sewage pool form a continuous circulating water flow. The fluid is mixed adequately and average velocity of fluid in the pool is at around 0.241m/s, which agreed with the work requirements. Consequently it can provide a reference basis for practical engineering application of submersible mixers by using this method.

  10. Mathematical modeling of the energy consumption of heated swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Le Bel, C.; Millette, J. [LTE Shawinigan, Shawinigan, PQ (Canada)

    2007-07-01

    A mathematical model was developed to estimate the water temperature of a residential swimming pool. The model can compare 2 different situations and, if local climatic conditions are known, it can accurately predict energy costs of the pool relative to the total energy consumption of the house. When used with the appropriate energy transfer coefficient and weather file, the model can estimate the water temperature of a residential swimming pool having specific characteristics, such as in-ground, above-ground, heated or non-heated. The model is suitable for determining residential loads. It can be applied to different pool types and sizes, for different water heating scenarios and different climatic regions. Data obtained from the monitoring of water temperature and electricity use of 57 residential swimming pools was used to validate the model. In addition, 5 above-ground pools were installed on the property of LTE Shawinigan to allow for a more detailed study of the parameters involved in the thermal balance of a pool. The mathematical model, based on a global heat transfer coefficient, can determine the effect of a solar blanket and the effect of water volume. 14 refs., 5 tabs., 11 figs.

  11. ENERGY SAVING AT OPERATION OF OUTDOOR SWIMMING POOLS

    Directory of Open Access Journals (Sweden)

    V. F. Ivin

    2013-09-01

    Full Text Available Purpose. Energy saving is a major problem in modern power engineering and various energy-consuming devices. They include outdoor swimming pools. In order to maintain them in working condition, especially in winter period, it takes significant amount of thermal energy. Task of heat loss substantial decrease in open swimming pools is considered in the article (on DNURT example. Methodology. The method of determining the mass and heat loss on the basis of criteria equations of heat and mass transfer theory is used. Findings. Calculations of the actual DNURT pool heat loss for different seasons, as for natural convection both for air forced motion above the free water surface are performed. It is shown that for the adiabatic evaporation conditions of water from the pool in winter during blow-off with wind the heat loss can be up to 2 kW/m2 on surface. To reduce these losses it is offered to cover water surface in a pool with a special material with low thermal conductivity on the basis of porous polyethylene during the time when the pool is not used for other purposes. It is shown that the implementation of these standards will reduce the actual heat loss, at least 5-6 times. Originality. The solution of important environmental and energy problem thanks to reducing heat losses by the pool in different times of a year and correspondingly lower emissions of power generating enterprises. Practical value. It is shown that the coating surface of the pool with poorly heat-conducting and easy to install coating will let, at a minimum, to reduce the actual heat loss on 5-6 times and reduce the emissions of power plants generating energy for pool heating.

  12. Flow dynamics of volume-heated boiling pools

    International Nuclear Information System (INIS)

    Ginsberg, T.; Jones, O.C.; Chen, J.C.

    1979-01-01

    Safety analyses of fast breeder reactors require understanding of the two-phase fluid dynamic and heat transfer characteristics of volume-heated boiling pool systems. Design of direct contact three-phase boilers, of practical interest in the chemical industries also requires understanding of the fundamental two-phase flow and heat transfer behavior of volume boiling systems. Several experiments have been recently reported relevant to the boundary heat-loss mechanisms of boiling pool systems. Considerably less is known about the two-phase fluid dynamic behavior of such systems. This paper describes an experimental investigation of the steady-state flow dynamics of volume-heated boiling pool systems

  13. Mitochondrial deoxyribonucleoside triphosphate pools in thymidine kinase 2 deficiency.

    Science.gov (United States)

    Saada, Ann; Ben-Shalom, Efrat; Zyslin, Rivka; Miller, Chaya; Mandel, Hanna; Elpeleg, Orly

    2003-10-24

    Deficiency of mitochondrial thymidine kinase (TK2) is associated with mitochondrial DNA (mtDNA) depletion and manifests by severe skeletal myopathy in infancy. In order to elucidate the pathophysiology of this condition, mitochondrial deoxyribonucleoside triphosphate (dNTP) pools were determined in patients' fibroblasts. Despite normal mtDNA content and cytochrome c oxidase (COX) activity, mitochondrial dNTP pools were imbalanced. Specifically, deoxythymidine triphosphate (dTTP) content was markedly decreased, resulting in reduced dTTP:deoxycytidine triphosphate ratio. These findings underline the importance of balanced mitochondrial dNTP pools for mtDNA synthesis and may serve as the basis for future therapeutic interventions.

  14. Non-electric applications of pool-type nuclear reactors

    International Nuclear Information System (INIS)

    Adamov, E.O.; Cherkashov, Yu.M.; Romenkov, A.A.

    1997-01-01

    This paper recommends the use of pool-type light water reactors for thermal energy production. Safety and reliability of these reactors were already demonstrated to the public by the long-term operation of swimming pool research reactors. The paper presents the design experience of two projects: Apatity Underground Nuclear Heating Plant and Nuclear Sea-Water Desalination Plant. The simplicity of pool-type reactors, the ease of their manufacturing and maintenance make this type of a heat source attractive to the countries without a developed nuclear industry. (author). 6 figs, 1 tab

  15. Macroinvertebrate community assembly in pools created during peatland restoration

    International Nuclear Information System (INIS)

    Brown, Lee E.; Ramchunder, Sorain J.; Beadle, Jeannie M.; Holden, Joseph

    2016-01-01

    Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

  16. Pool scrubbing and hydrodynamic experiment on jet injection regime

    Energy Technology Data Exchange (ETDEWEB)

    Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez, J.

    1995-07-01

    Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  17. Pool scrubbing and hydrodynamic experiment on jet injection regime

    International Nuclear Information System (INIS)

    Peyres, V.; Espigares, M.M.; Polo, J.; Escudero, M.J.; Herranz, L.E.; Lopez, J.

    1995-01-01

    Plant analyses nave shown that pool scrubbing can play an important role in source term during PWR risk dominant sequences. An examination of boundary conditions governing fission products and aerosols transport through aqueous beds revealed that most of radioactivity is discharged into the pool under jet injection regime. This fact and the lack of experimental data under such conditions pointed the need of setting out an experimental programme which provided reliable experimental data to validate code models. In this report the major results of a pool scrubbing experimental programme carried out in PECA facility are presented. One of the major findings was that a remarkable fraction of particle absorption was not a function of the residence time of bubbles rising through the pool. Such a contribution was assumed to be associated to aerosol removal mechanism acting at the pool entrance. As a consequence. a hydrodynamic experimental plan was launched to examine the gas behaviour during the initial stages in the pool. Size and shape of gas nuclei in the pool were measured and fitted to a lognormal distribution. Particularly, size was found to be quite sensitive to inlet gas flow and at minor extent to gas composition and pool temperature. SPARC90 and BUSCA-AUG92 were used to simulate the retention tests. Whereas SPARC90 showed a pretty good agreement with experimental data, BUSCA-AUG92 results were far away from measurements in all the cases. SPARC90 consistency apparently pointed out the important role of fission products and aerosols retention at the injection zone; nonetheless, a peer examination of pool scrubbing phenomenology at the pool entrance should be carried out to test both hydrodynamic and removal models. Hence, one of the major high lights drawn from this work was the need of further research under representative severe accident conditions (i.e., saturated pools, jet injection regimes, etc.), as well as separate effect tests to validate, improve and

  18. Macroinvertebrate community assembly in pools created during peatland restoration

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Lee E., E-mail: l.brown@leeds.ac.uk; Ramchunder, Sorain J.; Beadle, Jeannie M.; Holden, Joseph

    2016-11-01

    Many degraded ecosystems are subject to restoration attempts, providing new opportunities to unravel the processes of ecological community assembly. Restoration of previously drained northern peatlands, primarily to promote peat and carbon accumulation, has created hundreds of thousands of new open water pools. We assessed the potential benefits of this wetland restoration for aquatic biodiversity, and how communities reassemble, by comparing pool ecosystems in regions of the UK Pennines on intact (never drained) versus restored (blocked drainage-ditches) peatland. We also evaluated the conceptual idea that comparing reference ecosystems in terms of their compositional similarity to null assemblages (and thus the relative importance of stochastic versus deterministic assembly) can guide evaluations of restoration success better than analyses of community composition or diversity. Community composition data highlighted some differences in the macroinvertebrate composition of restored pools compared to undisturbed peatland pools, which could be used to suggest that alternative end-points to restoration were influenced by stochastic processes. However, widely used diversity metrics indicated no differences between undisturbed and restored pools. Novel evaluations of restoration using null models confirmed the similarity of deterministic assembly processes from the national species pool across all pools. Stochastic elements were important drivers of between-pool differences at the regional-scale but the scale of these effects was also similar across most of the pools studied. The amalgamation of assembly theory into ecosystem restoration monitoring allows us to conclude with more certainty that restoration has been successful from an ecological perspective in these systems. Evaluation of these UK findings compared to those from peatlands across Europe and North America further suggests that restoring peatland pools delivers significant benefits for aquatic fauna by

  19. Modeling of the Temperature Field Recovery in the Oil Pool

    Science.gov (United States)

    Khabibullin, I. L.; Davtetbaev, A. Ya.; Mar'in, D. F.; Khisamov, A. A.

    2018-05-01

    This paper considers the problem on mathematical modeling of the temperature field recovery in the oil pool upon termination of injection of water into the pool. The problem is broken down into two stages: injection of water and temperature and pressure recovery upon termination of injection. A review of the existing mathematical models is presented, analytical solutions for a number of cases have been constructed, and a comparison of the analytical solutions of different models has been made. In the general form, the expression has been obtained that permits determining the temperature change in the oil pool upon termination of injection of water (recovery of the temperature field).

  20. Core-concrete molten pool dynamics and interfacial heat transfer

    International Nuclear Information System (INIS)

    Benjamin, A.S.

    1980-01-01

    Theoretical models are derived for the heat transfer from molten oxide pools to an underlying concrete surface and from molten steel pools to a general concrete containment. To accomplish this, two separate effects models are first developed, one emphasizing the vigorous agitation of the molten pool by gases evolving from the concrete and the other considering the insulating effect of a slag layer produced by concrete melting. The resulting algebraic expressions, combined into a general core-concrete heat transfer representation, are shown to provide very good agreement with experiments involving molten steel pours into concrete crucibles

  1. CrN/AlN superlattice coatings synthesized by pulsed closed field unbalanced magnetron sputtering with different CrN layer thicknesses

    International Nuclear Information System (INIS)

    Lin Jianliang; Moore, John J.; Mishra, Brajendra; Pinkas, Malki; Zhang Xuhai; Sproul, William D.

    2009-01-01

    CrN/AlN superlattice coatings with different CrN layer thicknesses were prepared using a pulsed closed field unbalanced magnetron sputtering system. A decrease in the bilayer period from 12.4 to 3.0 nm and simultaneously an increase in the Al/(Cr + Al) ratio from 19.1 to 68.7 at.% were obtained in the CrN/AlN coatings when the Cr target power was decreased from 1200 to 200 W. The bilayer period and the structure of the coatings were characterized by means of low angle and high angle X-ray diffraction and transmission electron microscopy. The mechanical and tribological properties of the coatings were studied using the nanoindentation and ball-on-disc wear tests. It was found that CrN/AlN superlattice coatings synthesized in the current study exhibited a single phase face-centered cubic structure with well defined interfaces between CrN and AlN nanolayers. Decreases in the residual stress and the lattice parameter were identified with a decrease in the CrN layer thickness. The hardness of the coatings increased with a decrease in the bilayer period and the CrN layer thickness, and reached the highest value of 42 GPa at a bilayer period of 4.1 nm (CrN layer thickness of 1.5 nm, AlN layer thickness of 2.5 nm) and an Al/(Cr + Al) ratio of 59.3 at.% in the coatings. A low coefficient of friction of 0.35 and correspondingly low wear rate of 7 x 10 -7 mm 3 N -1 m -1 were also identified in this optimized CrN/AlN coating when sliding against a WC-6%Co ball.

  2. De novo unbalanced translocations in Prader-Willi and Angelman syndrome might be the reciprocal product of inv dup(15s.

    Directory of Open Access Journals (Sweden)

    Elena Rossi

    Full Text Available The 15q11-q13 region is characterized by high instability, caused by the presence of several paralogous segmental duplications. Although most mechanisms dealing with cryptic deletions and amplifications have been at least partly characterized, little is known about the rare translocations involving this region. We characterized at the molecular level five unbalanced translocations, including a jumping one, having most of 15q transposed to the end of another chromosome, whereas the der(15(pter->q11-q13 was missing. Imbalances were associated either with Prader-Willi or Angelman syndrome. Array-CGH demonstrated the absence of any copy number changes in the recipient chromosome in three cases, while one carried a cryptic terminal deletion and another a large terminal deletion, already diagnosed by classical cytogenetics. We cloned the breakpoint junctions in two cases, whereas cloning was impaired by complex regional genomic architecture and mosaicism in the others. Our results strongly indicate that some of our translocations originated through a prezygotic/postzygotic two-hit mechanism starting with the formation of an acentric 15qter->q1::q1->qter representing the reciprocal product of the inv dup(15 supernumerary marker chromosome. An embryo with such an acentric chromosome plus a normal chromosome 15 inherited from the other parent could survive only if partial trisomy 15 rescue would occur through elimination of part of the acentric chromosome, stabilization of the remaining portion with telomere capture, and formation of a derivative chromosome. All these events likely do not happen concurrently in a single cell but are rather the result of successive stabilization attempts occurring in different cells of which only the fittest will finally survive. Accordingly, jumping translocations might represent successful rescue attempts in different cells rather than transfer of the same 15q portion to different chromosomes. We also hypothesize that

  3. Evolution from increased cardiac mechanical function towards cardiomyopathy in the obese rat due to unbalanced high fat and abundant equilibrated diets

    Directory of Open Access Journals (Sweden)

    Mourmoura Evangelia

    2015-07-01

    Full Text Available The aim of our study was to know whether high dietary energy intake (HDEI with equilibrated and unbalanced diets in term of lipid composition modify the fatty acid profile of cardiac phospholipids and function of various cardiac cells and to know if the changes in membrane lipid composition can explain the modifications of cellular activity. Wistar rats were fed either a control or high-fat (HF diet for 12 weeks and Zucker diabetic fatty (ZDF rats as well as their lean littermate (ZL a control diet between week 7 to 11 of their life. Energy intake and abdominal obesity was increased in HF-fed and ZDF rats. Circulating lipids were also augmented in both strains although hyperglycemia was noticed only in ZDF rats. HDEI induced a decrease in linoleate and increase in arachidonate in membrane phospholipids which was more pronounced in the ZDF rats compared to the HF-fed rats. In vivo cardiac function (CF was improved in HF-fed rats whereas ex vivo cardiac function was unchanged, suggesting that environmental factors such as catecholamines stimulated the in vivo CF. The unchanged ex vivo CF was associated with an increased cardiac mass which indicated development of fibrosis and/or hypertrophy. The increased in vivo CF was sustained by an augmented coronary reserve which was related to the cyclooxygenase pathway and accumulation of arachidonate in membrane phospholipids. In conclusion, before triggering a diabetic cardiomyopathy, HDEI stimulated the CF. The development of cardiomyopathy seems to result from fibrosis and/or hypertrophy which augments myocardial stiffness and decreases contractility.

  4. The role of growth form and correlated traits in competitive ranking of six perennial ruderal plant species grown in unbalanced mixtures

    Science.gov (United States)

    Dietz, Hansjörg; Steinlein, Thomas; Ullmann, Isolde

    1998-02-01

    The competitive abilities of six perennial ruderal plants of three different growth forms were compared via yield measures using an additive diallel experimental design with unbalanced mixtures (9:3 or 3:9 plants per pot, respectively). Thus, in a given mixture species A was grown in two configurations: three individuals in centre position of the pot together with nine plants of species B in border position and vice versa. Effect competitive abilities as well as response competitive abilities of the species were significantly related to canopy height and plant biomass. The species with lower rosette growth form and smaller biomasses were weaker competitors than the species possessing elevated canopies along with higher biomasses, whereas total leaf area was not significantly correlated with competitive ability between species. Species differences in competitive ability were stronger between the plants grown in the central position than between those grown in the border position. Furthermore, interactions between species-specific traits and configuration could be observed, indicating the importance of species proportions and arrangement patterns for evaluation of competitive outcome in the field. The degree of complete transitivity of the competitive network of the six ruderal species, which was significantly higher than expected under the null model in our experimental design, also seemed to depend on species proportions in mixture. Shifts in root:shoot ratio of the centre plants when faced with competition by the border plants were in the direction of higher shoot allocation for the weak competitors with rosette growth form irrespective of the neighbour species, except for Bunias orientalis, which showed a more plastic response. The stronger competitors showed higher root allocation ( Urtica dioica) or were hardly affected at all. Consistent with the results of our experiment, the weaker competitors occur at rather frequently disturbed and therefore transient

  5. Fast Calculation Model and Theoretical Analysis of Rotor Unbalanced Magnetic Pull for Inter-Turn Short Circuit of Field Windings of Non-Salient Pole Generators

    Directory of Open Access Journals (Sweden)

    Guangtao Zhang

    2017-05-01

    Full Text Available Inter-turn short circuit of field windings (ISCFW may cause the field current of a generator to increase, output reactive power to decrease, and unit vibration to intensify, seriously affecting its safe and stable operation. Full integration of mechanical and electrical characteristics can improve the sensitivity of online monitoring, and detect the early embryonic period fault of small turns. This paper studies the calculations and variations of unbalanced magnetic pull (UMP, of which the excitation source of rotor vibration is the basis and key to online fault monitoring. In grid load operation, ISCFW are first calculated with the multi-loop method, so as to obtain the numerical solutions of the stator and the rotor currents during the fault. Next, the air-gap magnetic field of the ISCFW is analyzed according to the actual composition modes of the motor loops in the fault, so as to obtain the analytic expressions of the air-gap magnetic motive force (MMF and magnetic density. The UMP of the rotor is obtained by solving the integral of the Maxwell stress. The correctness of the electric quantity calculation is verified by the ISCFW experiment, conducted in a one pair-pole non-salient pole model machine. On this basis, comparing the simulation analysis with the calculation results of the model in this paper not only verifies the accuracy of the electromagnetic force calculation, but also proves that the latter has the advantages of a short time consumption and high efficiency. Finally, the influencing factors and variation law of UMP are analyzed by means of an analytic model. This develops a base for the online monitoring of ISCFW with the integration of mechanical and electrical information.

  6. Retail Demand Response in Southwest Power Pool

    Energy Technology Data Exchange (ETDEWEB)

    Bharvirkar, Ranjit; Heffner, Grayson; Goldman, Charles

    2009-01-30

    In 2007, the Southwest Power Pool (SPP) formed the Customer Response Task Force (CRTF) to identify barriers to deploying demand response (DR) resources in wholesale markets and develop policies to overcome these barriers. One of the initiatives of this Task Force was to develop more detailed information on existing retail DR programs and dynamic pricing tariffs, program rules, and utility operating practices. This report describes the results of a comprehensive survey conducted by LBNL in support of the Customer Response Task Force and discusses policy implications for integrating legacy retail DR programs and dynamic pricing tariffs into wholesale markets in the SPP region. LBNL conducted a detailed survey of existing DR programs and dynamic pricing tariffs administered by SPP's member utilities. Survey respondents were asked to provide information on advance notice requirements to customers, operational triggers used to call events (e.g. system emergencies, market conditions, local emergencies), use of these DR resources to meet planning reserves requirements, DR resource availability (e.g. seasonal, annual), participant incentive structures, and monitoring and verification (M&V) protocols. Nearly all of the 30 load-serving entities in SPP responded to the survey. Of this group, fourteen SPP member utilities administer 36 DR programs, five dynamic pricing tariffs, and six voluntary customer response initiatives. These existing DR programs and dynamic pricing tariffs have a peak demand reduction potential of 1,552 MW. Other major findings of this study are: o About 81percent of available DR is from interruptible rate tariffs offered to large commercial and industrial customers, while direct load control (DLC) programs account for ~;;14percent. o Arkansas accounts for ~;;50percent of the DR resources in the SPP footprint; these DR resources are primarily managed by cooperatives. o Publicly-owned cooperatives accounted for 54percent of the existing DR resources

  7. Pool Onistarist kuulub kütusefirma omanikele / Sirje Niitra

    Index Scriptorium Estoniae

    Niitra, Sirje, 1948-

    2001-01-01

    Alkoholikontserni Onistar kiiret tõusu Eesti alkoholiturul toetavad Vene rahvusest ärimeestele kuuluvate kütusefirmade Infast Oil ja Saurix Petroleum omanikud, kellele kuulub pool Eesti viinaturu liidri aktsiatest

  8. Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    1996-12-01

    The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included

  9. 41 CFR 101-25.109-2 - Equipment pools.

    Science.gov (United States)

    2010-07-01

    ... number and location of equipment pools, consideration shall be given to economy of operation, mobility of... available for sharing or loan. Information concerning the availability of this equipment can be maintained...

  10. Open Architecture, Inventory Pooling and Spare Maintenance Assets

    National Research Council Canada - National Science Library

    Ferrer, Geraldo

    2007-01-01

    .... This article focuses on the benefits provided by pooling together the inventory necessary to meet the demand of many users into a small number of storage sites with reduced product variety obtained...

  11. Investigation to radioactive contamination of pool water in IMEF

    International Nuclear Information System (INIS)

    Song, Ung Sup; Jung, Yang Hong; Lee, J. H.; Lee, H. K.

    2003-06-01

    The pool (3x6x10) in irradiated materials examination facility is usually used for the purpose of taking the specimen out of cask loaded into the pool, and carrying in/out the specimen to/ from the hot cell. Always, it must be cared for the water into the pool to be fine condition because all operation are worked with the naked eye during taking an irradiated materials out of the cask and plunging them in the bucket-elevator. In the aspects of the radioactive remained substances in the water must be controlled so that the amount of substances to be lower than the standard amount prescribed by RCA Korea Activity in a part of radioactive contamination control. In consequence, an expertness of status and a practical use of skill make possible the prevention of radioactive material's diffusion or the radioactive contamination of pool water and safety work

  12. Allegheny County Public Swimming Pool, Hot Tub, and Spa Inspections

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Public swimming pool, hot tub, and spa facilities are licensed and inspected once each year to assure proper water quality, sanitation, lifeguard coverage and...

  13. 17 CFR 229.1111 - (Item 1111) Pool assets.

    Science.gov (United States)

    2010-04-01

    ... information for the asset pool, including statistical information regarding delinquencies and losses. (d.... Present statistical information in tabular or graphical format, if such presentation will aid understanding. Present statistical information in appropriate distributional groups or incremental ranges in...

  14. Equilibrium blood pool scanning in the evaluation of hemophilic arthropathy

    International Nuclear Information System (INIS)

    Spies, S.; Green, D.; Rana, N.A.; Milgram, J.W.; Mintzer, R.

    1978-01-01

    Arthropathy was evaluated in six patients with severe hemophilia (factor VIII<1%) using the technique of blood pool scanning. Employing an in vivo method for erythrocyte labelling with technetium-99m, a dynamic perfusion sequence was obtained using a scintillation camera over the joint(s) to be examined. Subsequently, equilibrium blood pool images of the joints were obtained to determine regional blood volume. In young patients with repeated episodes of acute hemarthrosis, increased vascularity and increased blood pool in the affected joints were demonstrated. In older patients with fixed, contracted joints and degenerative arthropathy, vascularity and regional blood volume were not abnormal. Blood pool scanning is a safe, non-invasive technique that augments the clinical and radiographic examination of the joints. The method is helpful in distinguishing acute joint bleeding from chronic synovitis and arthritis, and may prove useful in selecting patients for synovectomy. (author)

  15. LCG Persistency Framework (POOL, CORAL, COOL) - Status and Outlook

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The LCG Persistency Framework consists of three software packages (POOL, CORAL and COOL) that address the data access requirements of the LHC experiments in several different areas. The project is the result of the collaboration between the CERN IT Department and the three experiments (ATLAS, CMS and LHCb) that are using some or all of the Persistency Framework components to access their data. The POOL package is a hybrid technology store for C++ objects, using a mixture of streaming and relational technologies to implement both object persistency and object metadata catalogs and collections. POOL provides generic components that can be used by the experiments to store both their event data and their conditions data. The CORAL package is an abstraction layer with an SQL-free API for accessing data stored using relational database technologies. It is used directly by experiment-specific applications and internally by both COOL and POOL. The COOL package provides specific software components and tools for the h...

  16. Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included.

  17. Condensation pool experiments with steam using DN200 blowdown pipe

    International Nuclear Information System (INIS)

    Laine, J.; Puustinen, M.

    2005-08-01

    This report summarizes the results of the condensation pool experiments with steam using a DN200 blowdown pipe. Altogether five experiment series, each consisting of several steam blows, were carried out in December 2004 with a scaled-down test facility designed and constructed at Lappeenranta University of Technology. The main purpose of the experiments was to increase the understanding of different phenomena in the condensation pool during steam discharge. (au)

  18. Optimization of spent fuel pool weir gate driving mechanism

    Science.gov (United States)

    Liu, Chao; Du, Lin; Tao, Xinlei; Wang, Shijie; Shang, Ertao; Yu, Jianjiang

    2018-04-01

    Spent fuel pool is crucial facility for fuel storage and nuclear safety, and the spent fuel pool weir gate is the key related equipment. In order to achieve a goal of more efficient driving force transfer, loading during the opening/closing process is analyzed and an optimized calculation method for dimensions of driving mechanism is proposed. The result of optimizing example shows that the method can be applied to weir gates' design with similar driving mechanism.

  19. CHARACTERISTICS OFBENTHIC FISH COMMUNITY OF DNIEPER STORAGE POOL LITTORAL ZONE

    Directory of Open Access Journals (Sweden)

    Novitskiy R. A.

    2011-11-01

    Full Text Available Specific composition of bull-calves is analyzed together with their quantitative and quality parameters in the littoral zone of the Dnepr storage pool. The structural-functional features of organization of littoral communities of bull-calves were studied. The patterns of spatial distribution of Bull-calf (Gobiidae representatives were analyzed for the storage pool; their role in the littoral fish communities was clarified.

  20. Research progresses and future directions on pool boiling heat transfer

    OpenAIRE

    M. Kumar; V. Bhutani; P. Khatak

    2015-01-01

    This paper reviews the previous work carried on pool boiling heat transfer during heating of various liquids and commodities categorized as refrigerants and dielectric fluids, pure liquids, nanofluids, hydrocarbons and additive mixtures, as well as natural and synthetic colloidal solutions. Nucleate pool boiling is an efficient and effective method of boiling because high heat fluxes are possible with moderate temperature differences. It is characterized by the growth of bubbles on a heated s...

  1. Analysis of natural convection in volumetrically-heated melt pools

    International Nuclear Information System (INIS)

    Sehgal, B.R.; Dinh, T.N.; Nourgaliev, R.R.

    1996-12-01

    Results of series of studies on natural convection heat transfer in decay-heated core melt pools which form in a reactor lower plenum during the progression of a core meltdown accident are described. The emphasis is on modelling and prediction of turbulent heat transfer characteristics of natural convection in a liquid pool with an internal energy source. Methods of computational fluid dynamics, including direct numerical simulation, were applied for investigation

  2. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.

  3. A swimming pool array for ultra high energy showers

    Science.gov (United States)

    Yodh, Gaurang B.; Shoup, Anthony; Barwick, Steve; Goodman, Jordan A.

    1992-11-01

    A very preliminary design concept for an array using water Cherenkov counters, built out of commercially available backyard swimming pools, to sample the electromagnetic and muonic components of ultra high energy showers at large lateral distances is presented. The expected performance of the pools is estimated using the observed lateral distributions by scintillator and water Cherenkov arrays at energies above 1019 eV and simulations.

  4. Lip and tooth injuries at public swimming pools in Austria.

    Science.gov (United States)

    Lechner, Katharina; Connert, Thomas; Kühl, Sebastian; Filippi, Andreas

    2017-06-01

    There is an increased risk of orofacial injuries in swimming pool facilities. Nevertheless, only a few studies have addressed this issue. The aim of this study was to identify the frequency of lip and tooth injuries at public swimming pools in Austria. A further aim was to examine which gender and age groups were affected, where and why these injuries occurred, and whether pool attendants had sufficient knowledge of dental first-aid measures. A total of 764 pool attendants in Austria were contacted by telephone and 689 participated in the study (90.2%). The attendants were interviewed retrospectively about accident occurrences in 2014 by a standardized questionnaire. Responses to the provision of first aid and choice of storage medium for avulsed teeth were subsequently evaluated. The frequency of lip injuries was 19.0%, and tooth injuries were 11.3%. Male bathers (P < .05) and children under 12 years (P < .001) most frequently suffered injuries. The waterslide was the most common accident site. The most common cause of lip injuries was slipping on wet surfaces (39.0%), and for tooth injuries it was collisions with other persons or objects (each 28.1%). The pool attendants' responses were predominantly good or sufficient on first aid, with the exception of what storage medium to choose. Tooth rescue boxes were available in only 8.6% of all pool facilities. Orofacial injuries are a frequently occurring problem in swimming pool facilities. The pool attendants' knowledge on first-aid care of tooth injuries could still be improved. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. A hierarchic sustainability dashboard to evaluate logistics pooling

    OpenAIRE

    Morana, Joëlle; Gonzalez-Feliu, Jesus

    2014-01-01

    Logistics pooling is now a major challenge in supply chain management, though it remains a little known activity in which the different actors involved use different approaches whose objectives are not always the same and with sometimes conflicting standpoints. This purpose of this article is to define, on the basis of a detailed analysis of the literature, a grid for interpreting and a dashboard for evaluating the sustainable performance of pooled delivery systems. Firstly, an analysis of th...

  6. Analysis of natural convection in volumetrically-heated melt pools

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, B.R.; Dinh, T.N.; Nourgaliev, R.R. [Royal Inst. of Tech., Stockholm (Sweden). Div. of Nuclear Power Safety

    1996-12-01

    Results of series of studies on natural convection heat transfer in decay-heated core melt pools which form in a reactor lower plenum during the progression of a core meltdown accident are described. The emphasis is on modelling and prediction of turbulent heat transfer characteristics of natural convection in a liquid pool with an internal energy source. Methods of computational fluid dynamics, including direct numerical simulation, were applied for investigation. Refs, figs, tabs.

  7. Competition and power pooling in the electricity industry

    International Nuclear Information System (INIS)

    Jasinski, P.; Yarrow, G.; Fusaro, P.

    1995-01-01

    Two contributions to the debate on power pooling and competition in the electricity supply industry are presented. In the first, the situation in England and Wales where power pooling was introduced shortly before privatization is analysed. Pooling has existed for many years in the USA but as an inter-generator arrangement designed to optimize production and costs. The British system sought in addition to establish a spot market in which bulk buyers as well as bulk suppliers could participate. There are however obvious weaknesses in the pool as a competitive market and it is argued that a combination of pooling arrangements and longer-term bilateral supply contracts are more likely to offer the prospect of workably competitive and efficient outcomes. The second contribution discusses how competitive markets will evolve in the USA under the new regime of less onerous regulation heralded by the Energy Policy Act if 1992 and the emergence of electricity trading markets which followed. In particular, the proposal by the California Public Utility commission favouring a mandatory Poolco is examined. Poolco would operate the transmission grid and dispatch generating plants while the utilities would retain ownership of transmission facilities and be required to supply the pool. This is seen as representing only partial deregulation and not to be consistent with moves to further competition and encourage free markets. (U.K.)

  8. Test Area North Pool Stabilization Project: Environmental assessment

    International Nuclear Information System (INIS)

    1996-05-01

    The Test Area North (TAN) Pool is located within the fenced TAN facility boundaries on the Idaho National Engineering Laboratory (INEL). The TAN pool stores 344 canisters of core debris from the March, 1979, Three Mile Island (TMI) Unit 2 reactor accident; fuel assemblies from Loss-of-Fluid Tests (LOFT); and Government-owned commercial fuel rods and assemblies. The LOFT and government owned commercial fuel rods and assemblies are hereafter referred to collectively as open-quotes commercial fuelsclose quotes except where distinction between the two is important to the analysis. DOE proposes to remove the canisters of TMI core debris and commercial fuels from the TAN Pool and transfer them to the Idaho Chemical Processing Plant (ICPP) for interim dry storage until an alternate storage location other than at the INEL, or a permanent federal spent nuclear fuel (SNF) repository is available. The TAN Pool would be drained and placed in an industrially and radiologically safe condition for refurbishment or eventual decommissioning. This environmental assessment (EA) identifies and evaluates environmental impacts associated with (1) constructing an Interim Storage System (ISS) at ICPP; (2) removing the TMI and commercial fuels from the pool and transporting them to ICPP for placement in an ISS, and (3) draining and stabilizing the TAN Pool. Miscellaneous hardware would be removed and decontaminated or disposed of in the INEL Radioactive Waste Management Complex (RWMC). This EA also describes the environmental consequences of the no action alternative

  9. LNG pool fire simulation for domino effect analysis

    International Nuclear Information System (INIS)

    Masum Jujuly, Muhammad; Rahman, Aziz; Ahmed, Salim; Khan, Faisal

    2015-01-01

    A three-dimensional computational fluid dynamics (CFD) simulation of liquefied natural gas (LNG) pool fire has been performed using ANSYS CFX-14. The CFD model solves the fundamental governing equations of fluid dynamics, namely, the continuity, momentum and energy equations. Several built-in sub-models are used to capture the characteristics of pool fire. The Reynolds-averaged Navier–Stokes (RANS) equation for turbulence and the eddy-dissipation model for non-premixed combustion are used. For thermal radiation, the Monte Carlo (MC) radiation model is used with the Magnussen soot model. The CFD results are compared with a set of experimental data for validation; the results are consistent with experimental data. CFD results show that the wind speed has significant contribution on the behavior of pool fire and its domino effects. The radiation contours are also obtained from CFD post processing, which can be applied for risk analysis. The outcome of this study will be helpful for better understanding of the domino effects of pool fire in complex geometrical settings of process industries. - Highlights: • Simulation of pool fire using computational fluid dynamics (CFD) model. • Integration of CFD based pool fire model with domino effect. • Application of the integrated CFD based domino effect analysis

  10. Seasonal variation in Chironomid emergence from coastal pools

    Directory of Open Access Journals (Sweden)

    Alexander T. Egan

    2015-07-01

    Full Text Available Understanding the phenology of emergences can be useful in determining seasonal chironomid life cycle patterns, which are often influenced by ice cover and temperature in cold climates. Lake Superior is the largest lake in North America and with a mean surface temperature of 3.9 °C influences regional climate. Coastal pools at Isle Royale, a wilderness archipelago in the northern part of the lake, occur in dense patches on low-gradient volcanic bedrock between the lakeshore and forest, creating variable microhabitats for Chironomidae. Four sites were sampled monthly from April to October, 2010. Surface-floating pupal exuviae were collected from a series of pools in two zones: a lower zone near the lake influenced by wave splash, and an upper zone near the forest and influenced by upland runoff. We used Jaccard’s and Whittaker’s diversity indexes to test community similarity across months. Temperature loggers in pools collected hourly readings for most of the study. Assemblage emergences were stable in upper pools, with significant similarity across late spring and summer months. Assemblages were seasonally variable in lower pools, with significant dissimilarity across spring, summer, and fall months. Few species in either zone were unique to spring or fall months. However, many summer species in the splash zone had a narrow emergence period occurring during calm weather following distinct increases in mean water temperature. Regardless of input of cold lake water to the lower zone, pools from both zones generally had corresponding temperature trends.

  11. Review of steam jet condensation in a water pool

    International Nuclear Information System (INIS)

    Kim, Y. S.; Song, C. H.; Park, C. K.; Kang, H. S.; Jeon, H. G.; Yoon, Y. J.

    2002-01-01

    In the advanced nuclear power plants including APR1400, the SDVS is adopted to increase the plant safety using the concept of feed-and-bleed operation. In the case of the TLOFW, the POSRV located at the top of the pressurizer is expected to open due to the pressurization of the reactor coolant system and discharges steam and/or water mixture into the water pool, where the mixture is condensed. During the condensation of the mixture, thermal-hydraulic loads such as pressure and temperature variations are induced to the pool structure. For the pool structure design, such thermal-hydraulic aspects should be considered. Understanding the phenomena of the submerged steam jet condensation in a water pool is helpful for system designers to design proper pool structure, sparger, and supports etc. This paper reviews and evaluates the steam jet condensation in a water pool on the physical phenomena of the steam condensation including condensation regime map, heat transfer coefficient, steam plume, steam jet condensation load, and steam jet induced flow

  12. Natural convection heat transfer in the molten metal pool

    International Nuclear Information System (INIS)

    Park, R.J.; Kim, S.B.; Kim, H.D.; Choi, S.M.

    1997-01-01

    Analytical studies using the FLOW-3D computer program have been performed on natural convection heat transfer of a high density molten metal pool, in order to evaluate the coolability of the corium pool. The FLOW-3D results on the temperature distribution and the heat transfer rate in the molten metal pool region have been compared and evaluated with the experimental data. The FLOW-3D results have shown that the developed natural convection flow contributes to the solidified crust formation of the high density molten metal pool. The present FLOW-3D results, on the relationship between the Nusselt number and the Rayleigh number in the molten metal pool region, are more similar to the calculated results of Globe and Dropkin's correlation than any others. The natural convection heat transfer in the low aspect ratio case is more substantial than that in the high aspect ratio case. The FLOW-3D results, on the temperature profile and on the heat transfer rate in the molten metal pool region, are very similar to the experimental data. The heat transfer rate of the internal heat generation case is higher than that of the bottom heating case at the same heat supply condition. (author)

  13. Detection of 41Ar diffusion from a TRIGA pool

    International Nuclear Information System (INIS)

    Foss, Scott; Nelson, George

    1990-01-01

    Argon-41 levels in very low concentrations in the reactor room air can be inferred from the rate of escape from the pool water surface. The rate of Argon-41 diffusion from pool water to room air was determined by the measurement of the activity buildup in containers of air in contact with the pool surface. The Argon-41 concentration in each container was measured by gamma-ray spectrometry with a calibrated GeLi detector. At 100 KW power with the water temperature at 10 deg. Celsius the total release of Argon-41 was determined to be 3.5e10±15% atoms for 80 minutes of operation. The corresponding activity released from the pool was 98.6 microcuries, while the total activity produced in the pool was 4900 microcuries. The diffusion coefficient of Argon-41 from the pool water surface to the air at this temperature was measured to be 3.14e-14 sec-cm 2 . (author)

  14. Structural analysis of the reactor pool for the RRRP

    International Nuclear Information System (INIS)

    Alberro, J.G.; Abbate, A.D.

    2005-01-01

    The purpose of the present document is to describe the structural design of the Reactor Pool relevant to the RRRP (Replacement Research Reactor Project) for the Australian Nuclear Science and Technology Organisation. The structural analysis required coordinated design, engineering, analysis, and fabrication efforts. The pool has been designed, manufactured, and inspected following as guideline the ASME Boiler and Pressure Vessel Code, which defines the requirements for the pool to withstand hydrostatic and mechanical forces, ensuring its integrity throughout its lifetime. Standard off-the-shelf finite element programs (Nastran and Ansys codes) were used to evaluate the pool and further qualify the design and its construction. Both global and local effect analyses were carried out. The global analysis covers the structural integrity of the pool wall (6 mm thick) considering the different load states acting on it, namely hydrostatic pressure, thermal expansion, and seismic event. The local analysis evaluates the structural behaviour of the pool at specific points resulting from the interaction among components. It is confirmed that maximum stresses and displacements fall below the allowable values required by the ASME Boiler and Pressure Vessel Code. The water pressure analysis was validated by means of a hydrostatic test. (authors)

  15. 76 FR 64085 - Post-2014 Resource Pool-Loveland Area Projects, Final Power Allocation

    Science.gov (United States)

    2011-10-17

    ... Resource Pool; Loveland Area Projects, General Eligibility Criteria. The resource pool for capacity and... transmission in Kansas. Final allocation of the Post-2014 Resource Pool; Loveland Area Projects, is contingent...

  16. Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool

    OpenAIRE

    Mančić Marko V.; Živković Dragoljub S.; Milosavljević Peđa M.; Todorović Milena N.

    2014-01-01

    Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming po...

  17. Pooled versus separate measurements of tree-ring stable isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Dorado Linan, Isabel, E-mail: isabel@gfz-potsdam.de [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Gutierrez, Emilia, E-mail: emgutierrez@ub.edu [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Helle, Gerhard, E-mail: ghelle@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Heinrich, Ingo, E-mail: heinrich@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Andreu-Hayles, Laia, E-mail: laiandreu@ub.edu [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Tree-Ring Laboratory, Lamont-Doherty Earth Observatory of Columbia University, Palisades NY (United States); Planells, Octavi, E-mail: leocarpus@hotmail.com [Universitat de Barcelona, Departament d' Ecologia, Diagonal 645, 08028, Barcelona (Spain); Leuenberger, Markus, E-mail: leuenberger@climate.unibe.ch [Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Oeschger Centre of Climate Change Research, University of Bern, Zaehringerstrasse 25, 3012 Bern (Switzerland); Buerger, Carmen, E-mail: buerger@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany); Schleser, Gerhard, E-mail: schleser@gfz-potsdam.de [German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Dendro Laboratory, Telegrafenberg, 14473, Potsdam (Germany)

    2011-05-01

    {delta}{sup 13}C and {delta}{sup 18}O of tree rings contain time integrated information about the environmental conditions weighted by seasonal growth dynamics and are well established as sources of palaeoclimatic and ecophysiological data. Annually resolved isotope chronologies are frequently produced by pooling dated growth rings from several trees prior to the isotopic analyses. This procedure has the advantage of saving time and resources, but precludes from defining the isotopic error or statistical uncertainty related to the inter-tree variability. Up to now only a few studies have compared isotope series from pooled tree rings with isotopic measurements from individual trees. We tested whether or not the {delta}{sup 13}C and the {delta}{sup 18}O chronologies derived from pooled and from individual tree rings display significant differences at two locations from the Iberian Peninsula to assess advantages and constraints of both methodologies. The comparisons along the period 1900-2003 reveal a good agreement between pooled chronologies and the two mean master series which were created by averaging raw individual values (Mean) or by generating a mass calibrated mean (MassC). In most of the cases, pooled chronologies show high synchronicity with averaged individual samples at interannual scale but some differences also show up especially when comparing {delta}{sup 18}O decadal to multi-decadal variations. Moreover, differences in the first order autocorrelation among individuals may be obscured by pooling strategies. The lack of replication of pooled chronologies prevents detection of a bias due to a higher mass contribution of one sample but uncertainties associated with the analytical process itself, as sample inhomogeneity, seems to account for the observed differences. - Research Highlights: {yields} Pooled {delta}{sup 13}C and {delta}{sup 18}O chronologies are expected to be similar to the mean. {yields} Empirical pooled chronologies {delta}{sup 13}C and

  18. Pooled versus separate measurements of tree-ring stable isotopes

    International Nuclear Information System (INIS)

    Dorado Linan, Isabel; Gutierrez, Emilia; Helle, Gerhard; Heinrich, Ingo; Andreu-Hayles, Laia; Planells, Octavi; Leuenberger, Markus; Buerger, Carmen; Schleser, Gerhard

    2011-01-01

    δ 13 C and δ 18 O of tree rings contain time integrated information about the environmental conditions weighted by seasonal growth dynamics and are well established as sources of palaeoclimatic and ecophysiological data. Annually resolved isotope chronologies are frequently produced by pooling dated growth rings from several trees prior to the isotopic analyses. This procedure has the advantage of saving time and resources, but precludes from defining the isotopic error or statistical uncertainty related to the inter-tree variability. Up to now only a few studies have compared isotope series from pooled tree rings with isotopic measurements from individual trees. We tested whether or not the δ 13 C and the δ 18 O chronologies derived from pooled and from individual tree rings display significant differences at two locations from the Iberian Peninsula to assess advantages and constraints of both methodologies. The comparisons along the period 1900-2003 reveal a good agreement between pooled chronologies and the two mean master series which were created by averaging raw individual values (Mean) or by generating a mass calibrated mean (MassC). In most of the cases, pooled chronologies show high synchronicity with averaged individual samples at interannual scale but some differences also show up especially when comparing δ 18 O decadal to multi-decadal variations. Moreover, differences in the first order autocorrelation among individuals may be obscured by pooling strategies. The lack of replication of pooled chronologies prevents detection of a bias due to a higher mass contribution of one sample but uncertainties associated with the analytical process itself, as sample inhomogeneity, seems to account for the observed differences. - Research Highlights: → Pooled δ 13 C and δ 18 O chronologies are expected to be similar to the mean. → Empirical pooled chronologies δ 13 C and δ 18 O and the mean show a high synchronicity. → Pooled chronologies differ

  19. Unbalanced Neuronal Circuits in Addiction

    OpenAIRE

    Volkow, Nora D.; Wang, Gen-Jack; Tomasi, Dardo; Baler, Ruben D.

    2013-01-01

    Through sequential waves of drug-induced neurochemical stimulation, addiction co-opts the brain's neuronal circuits that mediate reward, motivation, , to behavioral inflexibility and a severe disruption of self-control and compulsive drug intake. Brain imaging technologies have allowed neuroscientists to map out the neural landscape of addiction in the human brain and to understand how drugs modify it.

  20. Unbalanced neuronal circuits in addiction.

    Science.gov (United States)

    Volkow, Nora D; Wang, Gen-Jack; Tomasi, Dardo; Baler, Ruben D

    2013-08-01

    Through sequential waves of drug-induced neurochemical stimulation, addiction co-opts the brain's neuronal circuits that mediate reward, motivation to behavioral inflexibility and a severe disruption of self-control and compulsive drug intake. Brain imaging technologies have allowed neuroscientists to map out the neural landscape of addiction in the human brain and to understand how drugs modify it. Published by Elsevier Ltd.

  1. Convective Cold Pool Structure and Boundary Layer Recovery in DYNAMO

    Science.gov (United States)

    Savarin, A.; Chen, S. S.; Kerns, B. W.; Lee, C.; Jorgensen, D. P.

    2012-12-01

    One of the key factors controlling convective cloud systems in the Madden-Julian Oscillation (MJO) over the tropical Indian Ocean is the property of the atmospheric boundary layer. Convective downdrafts and precipitation from the cloud systems produce cold pools in the boundary layer, which can inhibit subsequent development of convection. The recovery time is the time it takes for the boundary layer to return to pre convective conditions. It may affect the variability of the convection on various time scales during the initiation of MJO. This study examines the convective cold pool structure and boundary layer recovery using the NOAA WP-3D aircraft observations, include the flight-level, Doppler radar, and GPS dropsonde data, collected during the Dynamics of MJO (DYNAMO) field campaign from November-December 2011. The depth and strength of convective cold pools are defined by the negative buoyancy, which can be computed from the dropsonde data. Convective downdraft can be affected by environmental water vapor due to entrainment. Mid-level dry air observed during the convectively suppressed phase of MJO seems to enhance convective downdraft, making the cold pools stronger and deeper. Recovery of the cold pools in the boundary layer is determined by the strength and depth of the cold pools and also the air-sea heat and moisture fluxes. Given that the water vapor and surface winds are distinct for the convectively active and suppressed phases of MJO over the Indian Ocean, the aircraft data are stratified by the two different large-scale regimes of MJO. Preliminary results show that the strength and depth of the cold pools are inversely correlated with the surrounding mid-level moisture. During the convectively suppressed phase, the recovery time is ~5-20 hours in relative weak wind condition with small air-sea fluxes. The recovery time is generally less than 6 hours during the active phase of MJO with moist mid-levels and stronger surface wind and air-sea fluxes.

  2. UPDG: Utilities package for data analysis of Pooled DNA GWAS

    Directory of Open Access Journals (Sweden)

    Ho Daniel WH

    2012-01-01

    Full Text Available Abstract Background Despite being a well-established strategy for cost reduction in disease gene mapping, pooled DNA association study is much less popular than the individual DNA approach. This situation is especially true for pooled DNA genomewide association study (GWAS, for which very few computer resources have been developed for its data analysis. This motivates the development of UPDG (Utilities package for data analysis of Pooled DNA GWAS. Results UPDG represents a generalized framework for data analysis of pooled DNA GWAS with the integration of Unix/Linux shell operations, Perl programs and R scripts. With the input of raw intensity data from GWAS, UPDG performs the following tasks in a stepwise manner: raw data manipulation, correction for allelic preferential amplification, normalization, nested analysis of variance for genetic association testing, and summarization of analysis results. Detailed instructions, procedures and commands are provided in the comprehensive user manual describing the whole process from preliminary preparation of software installation to final outcome acquisition. An example dataset (input files and sample output files is also included in the package so that users can easily familiarize themselves with the data file formats, working procedures and expected output. Therefore, UPDG is especially useful for users with some computer knowledge, but without a sophisticated programming background. Conclusions UPDG provides a free, simple and platform-independent one-stop service to scientists working on pooled DNA GWAS data analysis, but with less advanced programming knowledge. It is our vision and mission to reduce the hindrance for performing data analysis of pooled DNA GWAS through our contribution of UPDG. More importantly, we hope to promote the popularity of pooled DNA GWAS, which is a very useful research strategy.

  3. Biophysical Interactions within Step-Pool Mountain Streams Following Wildfire

    Science.gov (United States)

    Parker, A.; Chin, A.; O'Dowd, A. P.

    2014-12-01

    Recovery of riverine ecosystems following disturbance is driven by a variety of interacting processes. Wildfires pose increasing disturbances to riverine landscapes, with rising frequencies and magnitudes owing to warming climates and increased fuel loads. The effects of wildfire include loss of vegetation, elevated runoff and flash floods, erosion and deposition, and changing biological habitats and communities. Understanding process interactions in post-fire landscapes is increasingly urgent for successful management and restoration of affected ecosystems. In steep channels, steps and pools provide prominent habitats for organisms and structural integrity in high energy environments. Step-pools are typically stable, responding to extreme events with recurrence intervals often exceeding 50 years. Once wildfire occurs, however, intensification of post-fire flood events can potentially overpower the inherent stability of these systems, with significant consequences for aquatic life and human well-being downstream. This study examined the short-term response of step-pool streams following the 2012 Waldo Canyon Fire in Colorado. We explored interacting feedbacks among geomorphology, hydrology, and ecology in the post-fire environment. At selected sites with varying burn severity, we established baseline conditions immediately after the fire with channel surveys, biological assessment using benthic macroinvertebrates, sediment analysis including pebble counts, and precipitation gauging. Repeat measurements after major storm events over several years enabled analysis of the interacting feedbacks among post-fire processes. We found that channels able to retain the step-pool structure changed less and facilitated recovery more readily. Step habitats maintained higher percentages of sensitive macroinvertebrate taxa compared to pools through post-fire floods. Sites burned with high severity experienced greater reduction in the percentage of sensitive taxa. The decimation of

  4. Experimental investigation of particulate debris spreading in a pool

    Energy Technology Data Exchange (ETDEWEB)

    Konovalenko, A., E-mail: kono@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Basso, S., E-mail: simoneb@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Kudinov, P., E-mail: pkudinov@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Yakush, S.E., E-mail: yakush@ipmnet.ru [Institute for Problems in Mechanics of the Russian Academy of Sciences, Ave. Vernadskogo 101 Bldg 1, Moscow 119526 (Russian Federation)

    2016-02-15

    Termination of severe accident progression by core debris cooling in a deep pool of water under reactor vessel is considered in several designs of light water reactors. However, success of this accident mitigation strategy is contingent upon the effectiveness of heat removal by natural circulation from the debris bed. It is assumed that a porous bed will be formed in the pool in the process of core melt fragmentation and quenching. Debris bed coolability depends on its properties and system conditions. The properties of the bed, including its geometry are the outcomes of the debris bed formation process. Spreading of the debris particles in the pool by two-phase turbulent flows induced by the heat generated in the bed can affect the shape of the bed and thus influence its coolability. The goal of this work is to provide experimental data on spreading of solid particles in the pool by large-scale two-phase flow. The aim is to provide data necessary for understanding of separate effects and for development and validation of models and codes. Validated codes can be then used for prediction of debris bed formation under prototypic severe accident conditions. In PDS-P (Particulate Debris Spreading in the Pool) experiments, air injection at the bottom of the test section is employed as a means to create large-scale flow in the pool in isothermal conditions. The test section is a rectangular tank with a 2D slice geometry, it has fixed width (72 mm), adjustable length (up to 1.5 m) and allows water filling to the depth of up to 1 m. Variable pool length and depth allows studying two-phase circulating flows of different characteristic sizes and patterns. The average void fraction in the pool is determined by video recording and subsequent image processing. Particles are supplied from the top of the facility above the water surface. Results of several series of PDS-P experiments are reported in this paper. The influence of the gas flow rate, pool dimensions, particle density

  5. Pool swell sub-scale testing and code comparison

    International Nuclear Information System (INIS)

    Elisson, K.

    1981-01-01

    The main objective of the experiment was to investigate the pool swell dynamics in general and the forces on the lowered central part of the diaphragm between drywell and wetwell in particular. Apart from the high speed camera pressure transducers and strain gauges were used to monitor the transient. Data was recorded on a 14 channel FM recorder and then digitalised and plotted. In total more than one hundred tests were performed including parametric variations of for example geometry, break flow, initial drywell pressure and initial water level. In parallel to this experiment pool swell calculations have been performed with the computer codes COPTA and STEALTH. COPTA which is a lumped mass code for pressure suppression containment analysis has a slug pool swell mode. STEALTH which is a general purpose lagrangian hydrodynamics code has been used in a 2-D axisymmetric version. The STEALTH code has been used to calculate the radial variations in the vertical displacement and velocity of the pool surface and to predict the load on the lowered central part of the diaphragm. A comparison between the calculations and the experimental data indicates that both codes are sufficiently correct in their description of the pool swell transient. (orig.)

  6. Immobilization of radioactive waste sludge from spent fuel storage pool

    International Nuclear Information System (INIS)

    Pavlovic, R.; Plecas, I.

    1998-01-01

    In the last forty years, in FR Yugoslavia, as result of the research reactors' operation and radionuclides application in medicine, industry and agriculture, radioactive waste materials of the different categories and various levels of specific activities were generated. As a temporary solution, these radioactive waste materials are stored in the two hanger type interim storages for solid waste and some type of liquid waste packed in plastic barrels, and one of three stainless steal underground containers for other types of liquid waste. Spent fuel elements from nuclear reactors in the Vinca Institute have been temporary stored in water filled storage pool. Due to the fact that the water in the spent fuel elements storage pool have not been purified for a long time, all metallic components submerged in the water have been hardly corroded and significant amount of the sludge has been settled on the bottom of the pool. As a first step in improving spent fuel elements storage conditions and slowing down corrosion in the storage spent fuel elements pool we have decided to remove the sludge from the bottom of the pool. Although not high, but slightly radioactive, this sludge had to be treated as radioactive waste material. Some aspects of immobilisation, conditioning and storage of this sludge are presented in this paper. (author

  7. Research progresses and future directions on pool boiling heat transfer

    Directory of Open Access Journals (Sweden)

    M. Kumar

    2015-12-01

    Full Text Available This paper reviews the previous work carried on pool boiling heat transfer during heating of various liquids and commodities categorized as refrigerants and dielectric fluids, pure liquids, nanofluids, hydrocarbons and additive mixtures, as well as natural and synthetic colloidal solutions. Nucleate pool boiling is an efficient and effective method of boiling because high heat fluxes are possible with moderate temperature differences. It is characterized by the growth of bubbles on a heated surface. It occurs during boiling of liquids for excess temperature ranging from 5 to 30 °C in various processes related to high vaporization of liquid for specific purposes like sugarcane juice heating for jaggery making, milk heating for khoa making, steam generation, cooling of electronic equipments, refrigeration and etcetera. In this review paper, pool boiling method during heating of liquids for specific purpose is depicted. It is inferred that enhancement in pool boiling heat transfer is a challenging and complex task. Also, recent research and use of various correlations for natural convection pool boiling is reviewed.

  8. SBWR PCCS vent phenomena and suppression pool mixing

    Energy Technology Data Exchange (ETDEWEB)

    Coddington, P. [Thermal-Hydraulics Lab., Paul Scherrer Institute, Villigen (Switzerland); Andreani, M. [Nuclear Engineering Lab., Swiss Federal Institute of Technology, Zurich (Switzerland)

    1995-09-01

    The most important phenomena influencing the effectiveness of the pressure suppression capability of the water pool within the Wetwell compartment of the SBWR Containment, during the period of Passive Containment Cooling System (PCCS) venting, have been critically reviewed. In addition, calculations have been carried-out to determine the condensation of the vented steam and the distribution of the energy deposited in the liquid pool. It has been found that a large contribution to the vapour suppression is due to condensation inside the vent pipe. The condensation rate of the steam inside the bubbles, produced at the vent exit, during their rise to the surface, may however be rather low, because of the large size bubbles. This can lead to vapour channelling to the Wetwell gas space. The above comments are likely to be ameliorated if the vent exit is a distributed source or sparger. Due to the large water flow rates within the {open_quotes}bubbly two-phase plume{close_quotes} generated by the gas injection, the water in the pool above the vent exit is likely to be heated nearly isothermally (perfect mixing). The effect of the suppression pool walls would be to enhance the recirculation and, consequently to promote mixing. The large size of the bubbles therein and of the walls on pool mixing are the most severe difficulties in extrapolating the results from scaled experiments to prototypical conditions.

  9. Water inventory management in condenser pool of boiling water reactor

    International Nuclear Information System (INIS)

    Gluntz, D.M.

    1996-01-01

    An improved system for managing the water inventory in the condenser pool of a boiling water reactor has means for raising the level of the upper surface of the condenser pool water without adding water to the isolation pool. A tank filled with water is installed in a chamber of the condenser pool. The water-filled tank contains one or more holes or openings at its lowermost periphery and is connected via piping and a passive-type valve (e.g., squib valve) to a high-pressure gas-charged pneumatic tank of appropriate volume. The valve is normally closed, but can be opened at an appropriate time following a loss-of-coolant accident. When the valve opens, high-pressure gas inside the pneumatic tank is released to flow passively through the piping to pressurize the interior of the water-filled tank. In so doing, the initial water contents of the tank are expelled through the openings, causing the water level in the condenser pool to rise. This increases the volume of water available to be boiled off by heat conducted from the passive containment cooling heat exchangers. 4 figs

  10. Determination of isotopomers in pools of molecules with polyisotopic elements

    International Nuclear Information System (INIS)

    Zyakun, A.M.; Brenninkmeijer, C.A.M.

    2002-01-01

    Polyisotopic element atoms that are present in a molecule form a pool of isotopomer molecules. Mono- and polyisotopomers are distinguished depending on the quantity of atoms of polyisotopic elements. Methodical approaches have been considered for the quantitative determination of the isotope composition of an element included in mono- and polyisotopic molecules. A possibility of the equally probable (homogeneous) and non-equally probable (non-homogeneous) distribution of isotopes of a polyisotopic element, the atoms of which have different positions in the molecule of polyisotopomer, has been shown. Factors disturbing the homogeneous distribution of isotopes of the element in the polyisotopomer pool have been revealed. When a polyisotopomer is involved in a mass-dependent process or reaction, the homogeneity of isotope distribution of the element is disturbed both in the residual and newly formed pools of polyisotopomer. By the example of CO 2 (polyisotopomer by oxygen) it has been shown that one can judge of the history of the analyzed pool formation by distribution of oxygen isotopes within this pool. The isotope content in the oxygen sites of polyisotopomer is a diagnostic feature of CO 2 involvement in the efflux from a reservoir or influx to the analyzed reservoir from an external source. (author)

  11. Gene Pools and the Genetic Architecture of Domesticated Cowpea

    Directory of Open Access Journals (Sweden)

    Bao-Lam Huynh

    2013-11-01

    Full Text Available Cowpea [ (L. Walp.] is a major tropical legume crop grown in warm to hot areas throughout the world and especially important to the people of sub-Saharan Africa where the crop was domesticated. To date, relatively little is understood about its domestication origins and patterns of genetic variation. In this study, a worldwide collection of cowpea landraces and African ancestral wild cowpea was genotyped with more than 1200 single nucleotide polymorphism markers. Bayesian inference revealed the presence of two major gene pools in cultivated cowpea in Africa. Landraces from gene pool 1 are mostly distributed in western Africa while the majority of gene pool 2 are located in eastern Africa. Each gene pool is most closely related to wild cowpea in the same geographic region, indicating divergent domestication processes leading to the formation of two gene pools. The total genetic variation within landraces from countries outside Africa was slightly greater than within African landraces. Accessions from Asia and Europe were more related to those from western Africa while accessions from the Americas appeared more closely related to those from eastern Africa. This delineation of cowpea germplasm into groups of genetic relatedness will be valuable for guiding introgression efforts in breeding programs and for improving the efficiency of germplasm management.

  12. Health impact of disinfection by-products in swimming pools

    Directory of Open Access Journals (Sweden)

    Cristina M. Villanueva

    2012-12-01

    Full Text Available This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks.

  13. Evaluation of Total Coliform, Fecal Coliform and Residual Chlorine in Swimming Pools in Kermanshah on the Season, the type of Pool, Disinfection System and Source of Water Supply in the during of three years (2010-2012

    Directory of Open Access Journals (Sweden)

    K SHarafi

    2014-11-01

    From the results , although the pools of water quality parameters has been studied in almost ideal But in summer, especially on a female pools and pools with wells water supply source than other pools , to be more oversight .

  14. Prediction of pool void fraction by new drift flux correlation

    International Nuclear Information System (INIS)

    Kataoka, I.; Ishii, M.

    1986-06-01

    A void fraction for a bubbling or boiling pool system is one of the important parameters in analyzing heat and mass transfer processes. Using the drift flux formulation, correlations for the pool void fraction have been developed in collaboration with a large number of experimental data. It has been found that the drift velocity in a pool system depends upon vessel diameter, system pressure, gas flux and fluid physical properties. The results show that the relative velocity and void fraction can be quite different from those predicted by conventional correlations. In terms of the rise velocity, four different regimes are identified. These are bubbly, churn-turbulent, slug and cap bubble regimes. The present correlations are shown to agree with the experimental data over wide ranges of parameters such as vessel diameter, system pressure, gas flux and physical properties. 39 refs., 41 figs

  15. Models for Pooled Time-Series Cross-Section Data

    Directory of Open Access Journals (Sweden)

    Lawrence E Raffalovich

    2015-07-01

    Full Text Available Several models are available for the analysis of pooled time-series cross-section (TSCS data, defined as “repeated observations on fixed units” (Beck and Katz 1995. In this paper, we run the following models: (1 a completely pooled model, (2 fixed effects models, and (3 multi-level/hierarchical linear models. To illustrate these models, we use a Generalized Least Squares (GLS estimator with cross-section weights and panel-corrected standard errors (with EViews 8 on the cross-national homicide trends data of forty countries from 1950 to 2005, which we source from published research (Messner et al. 2011. We describe and discuss the similarities and differences between the models, and what information each can contribute to help answer substantive research questions. We conclude with a discussion of how the models we present may help to mitigate validity threats inherent in pooled time-series cross-section data analysis.

  16. Human parvovirus PARV4 in plasma pools of Chinese origin.

    Science.gov (United States)

    Ma, Y-Y; Guo, Y; Zhao, X; Wang, Z; Lv, M-M; Yan, Q-P; Zhang, J-G

    2012-10-01

    Human parvovirus 4 (PARV4) is present in blood and blood products. As the presence and levels of PARV4 in Chinese source plasma pools have never been determined, we implemented real-time quantitative PCR to investigate the presence of PARV4 in source plasma pools in China. Results showed that 26·15% (51/195) of lots tested positive for PARV4. The amounts of DNA ranged from 2·83 × 10(3) copies/ml to 2·35×10(7) copies/ml plasma. The high level of PARV4 in plasma pools may pose a potential risk to recipients. Further studies on the pathogenesis of PARV4 are urgently required. © 2012 The Author(s). Vox Sanguinis © 2012 International Society of Blood Transfusion.

  17. Lin28a regulates germ cell pool size and fertility

    Science.gov (United States)

    Shinoda, Gen; de Soysa, T. Yvanka; Seligson, Marc T.; Yabuuchi, Akiko; Fujiwara, Yuko; Huang, Pei Yi; Hagan, John P.; Gregory, Richard I.; Moss, Eric G.; Daley, George Q.

    2013-01-01

    Overexpression of LIN28A is associated with human germ cell tumors and promotes primordial germ cell (PGC) development from embryonic stem cells in vitro and in chimeric mice. Knockdown of Lin28a inhibits PGC development in vitro, but how constitutional Lin28a deficiency affects the mammalian reproductive system in vivo remains unknown. Here, we generated Lin28a knockout (KO) mice and found that Lin28a deficiency compromises the size of the germ cell pool in both males and females by affecting PGC proliferation during embryogenesis. Interestingly however, in Lin28a KO males the germ cell pool partially recovers during postnatal expansion, while fertility remains impaired in both males and females mated to wild type mice. Embryonic overexpression of let-7, a microRNA negatively regulated by Lin28a, reduces the germ cell pool, corroborating the role of the Lin28a/let-7 axis in regulating the germ lineage. PMID:23378032

  18. Safety analysis of a pool Genesis II irradiator

    International Nuclear Information System (INIS)

    Rodrigues Junior, Ary de A.

    2011-01-01

    The Genesis II Irradiator manufactured by GRAT * STAR Inc. (USA) is a category III gamma irradiator in which the sealed source is contained in a water filled storage pool and is shielded permanently, i.e. the material has to move down to the source. Even though the pool is 5.6 m deep, what would happen if the water level lowered? There are a series of safety devices that will avoid this situation and calculations show that the water level has to be very low in order to deliver a significant dose; moreover, only in case a person remains at the border of the pool for a long time this would be risky. In conclusion, it is practically impossible for someone to be exposed to radiation from a Genesis II Irradiator source. (author)

  19. Core disruptive accident and recriticality analysis with FX2-POOL

    International Nuclear Information System (INIS)

    Abramson, P.B.

    1976-01-01

    The current state of development of FX2-POOL, a two-dimensional hydrodynamic, thermodynamic and neutronic scoping model for Hypothetical Core Disruptive Accident analysis is described. Checkout comparisons to VENUS for prompt burst conditions were good. Use of FX2-POOL to examine the importance of fuel to steel heat transfer during a prompt burst indicates that heat transfer plays no important role on that time scale. Scoping studies of material thermohydrodynamics for about 20 to 30 milliseconds following the prompt burst indicate that heat transfer is important on the time scale necessary for the CDA bubble to grow to the size of the original core. Preliminary results are presented for energetics of boiling fuel steel pools which are forced recritical by local surface pressurization

  20. CFD modeling of pool swell during large break LOCA

    International Nuclear Information System (INIS)

    Yan, Jin; Bolger, Francis; Li, Guangjun; Mintz, Saul; Pappone, Daniel

    2009-01-01

    GE had conducted a series of one-third scale three-vent air tests in support the horizontal vent pressure suppression system used in Mark III containment design for General Electric BWR plants. During the test, the air-water interface has been tracked by conductivity probes. There are many pressure monitors inside the test rig. The purpose of the test was to provide a basis for the pool swell load definition for the Mark III containment. In this paper, a transient 3-Dimensional CFD model of the one-third scale Mark III suppression pool swell process is constructed. The Volume of Fluid (VOF) multiphase model is used to explicitly track the interface between the water liquid and the air. The CFD results such as flow velocity, pressure, interface locations are compared to those from the test. Through the comparisons, a technical approach to numerically model the pool swell phenomenon is established and benchmarked. (author)

  1. Analysis of radiation shields of BNPP spent fuel pool

    International Nuclear Information System (INIS)

    Ayoobian, N.; Hadad, K.; Nematollahi, M. R.

    2007-01-01

    Radioactive protection is one of the most important subjects in nuclear power plants safety. Analysis of BNPP spent fuel pool shielding , as a main source of energetic γ-rays was the main goal of this project. Firstly, we simulated the reactor core using WIMSD-4 neutronic code and the amount of fission product in the fuel assembly (FA) was calculated during the reactor operation. Then, by obtaining the results from the previous calculation and by using MCNP4C nuclear code , the intensity of γ-rays was obtained in layers of spent fuel pool shields. The results have shown that no significant γ-rays passed through these shields. Finally, an accident and resulting exposure dose above the pool was analyzed

  2. Insertion sequences enrichment in extreme Red sea brine pool vent

    KAUST Repository

    Elbehery, Ali H. A.

    2016-12-03

    Mobile genetic elements are major agents of genome diversification and evolution. Limited studies addressed their characteristics, including abundance, and role in extreme habitats. One of the rare natural habitats exposed to multiple-extreme conditions, including high temperature, salinity and concentration of heavy metals, are the Red Sea brine pools. We assessed the abundance and distribution of different mobile genetic elements in four Red Sea brine pools including the world’s largest known multiple-extreme deep-sea environment, the Red Sea Atlantis II Deep. We report a gradient in the abundance of mobile genetic elements, dramatically increasing in the harshest environment of the pool. Additionally, we identified a strong association between the abundance of insertion sequences and extreme conditions, being highest in the harshest and deepest layer of the Red Sea Atlantis II Deep. Our comparative analyses of mobile genetic elements in secluded, extreme and relatively non-extreme environments, suggest that insertion sequences predominantly contribute to polyextremophiles genome plasticity.

  3. Spent nuclear fuel storage pool thermal-hydraulic analysis

    International Nuclear Information System (INIS)

    Gay, R.R.

    1984-01-01

    Storage methods and requirements for spent nuclear fuel at U.S. commercial light water reactors are reviewed in Section 1. Methods of increasing current at-reactor storage capabilities are also outlined. In Section 2 the development of analytical methods for the thermal-hydraulic analysis of spent fuel pools is chronicled, leading up to a discussion of the GFLOW code which is described in Section 3. In Section 4 the verification of GFLOW by comparisons of the code's predictions to experimental data taken inside the fuel storage pool at the Maine Yankee nuclear power plant is presented. The predictions of GFLOW using 72, 224, and 1584 node models of the storage pool are compared to each other and to the experimental data. An example of thermal licensing analysis for Maine Yankee using the GFLOW code is given in Section 5. The GFLOW licensing analysis is compared to previous licensing analysis performed by Yankee Atomic using the RELAP-4 computer code

  4. High efficiency pool filtering systems utilising variable frequency drives

    Energy Technology Data Exchange (ETDEWEB)

    Hameiri, Z.; Sproul, A.B. [School of Photovoltaic and Renewable Energy Engineering, UNSW, Sydney, NSW 2052 (Australia); Spooner, T. [School of Electrical Engineering and Telecommunications, UNSW, Sydney, NSW 2052 (Australia)

    2009-02-15

    Over 1 year, private swimming pools in Australia will typically consume 1680 GWh of electricity, producing 2130 kt of CO{sub 2}. Redesigning a pool's filtration system and using it more efficiently can reduce the energy use, and hence the CO{sub 2} production, by a significant amount. This paper describes experimental measurements carried out on a new design of pool pump system. Initial experiments using a variable frequency drive (VFD) with a standard, single phase pump/motor system have achieved energy savings of 40%. Utilising a VFD and a three phase pump/motor energy savings of 61% have been achieved, without degrading the system performance. (author)

  5. Analyzing data distribution on disk pools for dCache

    Energy Technology Data Exchange (ETDEWEB)

    Halstenberg, S; Jung, C; Ressmann, D [Forschungszentrum Karlsruhe, Steinbuch Centre for Computing, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2010-04-01

    Most Tier-1 centers of LHC Computing Grid are using dCache as their storage system. dCache uses a cost model incorporating CPU and space costs for the distribution of data on its disk pools. Storage resources at Tier-1 centers are usually upgraded once or twice a year according to given milestones. One of the effects of this procedure is the accumulation of heterogeneous hardware resources. For a dCache system, a heterogeneous set of disk pools complicates the process of weighting CPU and space costs for an efficient distribution of data. In order to evaluate the data distribution on the disk pools, the distribution is simulated in Java. The results are discussed and suggestions for improving the weight scheme are given.

  6. Inferring local ecological processes amid species pool influences

    DEFF Research Database (Denmark)

    Lessard, Jean-Philippe; Belmaker, Jonathan; Myers, Jonathan A.

    2012-01-01

    studies, null models of community structure, and ecologically explicit definitions of the species pool as a means to compare predominant ecological processes among regions. By uniting concepts and tools from community ecology and macroecology, this approach might facilitate synthesis and resolve many......Resolving contingencies in community ecology requires comparative studies of local communities along broad-scale environmental gradients and in different biogeographic regions. However, comparisons of local ecological processes among regions require a synthetic understanding of how the species pool...... of potential community members influences the structure of ecological communities. Here, we outline an integrative approach for quantifying local ecological processes while explicitly accounting for species pool influences. Specifically, we highlight the utility of combining geographically replicated local...

  7. CAREM 25: Suppression pool cooling and purification system

    International Nuclear Information System (INIS)

    Carlevaris, Rodolfo; Patrignani, Alberto; Vindrola, Carlos; Palmerio, Hector D.; Quiroz, Horacio; Ramilo, Lucia B.

    2000-01-01

    The suppression pool cooling and purification system has the following main functions: purify and cool water from the suppression pool, cool and send water to the residual heat extraction system, and transfer water to the fuel element transference channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the suppression pool to the spray network, thus cooling and reducing pressure in the primary containment. The system has been designed in accordance with the requirements of the following standards: ANSI/ANS 52.1; ANSI/ANS 57.2; ANSI/ANS 56.2; ANSI/ANS 59.1; ANSI/ANS 58.3; ANSI/ANS 58.9; and ANSI/ANS 56.5. The design of the system fulfils all the assigned functions. (author)

  8. CAREM-25. Suppression Pool Cooling and Purification System

    International Nuclear Information System (INIS)

    Carlevaris, Rodolfo; Palmerio, D.; Patrignani, A.; Quiroz, H.; Ramilo, L.; Vindrola, C.

    2000-01-01

    The Suppression Pool Cooling and Purification System has the following main functions: purify and cool water from the Suppression Pool, cool and send water to the Residual Heat Extraction System, and transfer water to the Fuel Element Transference Channel. In case of Loss of Coolant Accident (LOCA), the system sends water from the Suppression Pool to the spray network, thus cooling and reducing pressure in the primary containment.The system has been designed in accordance with the requirements of the following standards ANSI/ANS 52.1 [1], ANSI/ANS 57.2 [2], ANSI/ANS 56.2 [3], ANSI/ANS 59.1 [4] ANSI/ANS 58.3 [5], ANSI/ANS 58.9 [6], and ANSI/ANS 56.5 [7]. The design of the system fulfils all the assigned functions

  9. Analysis of the loss of pool cooling accident in a PWR spent fuel pool with MAAP5

    International Nuclear Information System (INIS)

    Wu, Xiaoli; Li, Wei; Zhang, Yapei; Tian, Wenxi; Su, Guanghui; Qiu, Suizheng

    2014-01-01

    Highlights: • A PWR spent fuel pool was modeled by using MAAP5. • Loss of pool cooling severe accident scenarios were studied. • Loss of pool cooling accidents with two mitigation measures were analyzed. - Abstract: The Fukushima Daiichi nuclear accident shows that it is necessary to study potential severe accidents and corresponding mitigation measures for the spent fuel pool (SFP) of a nuclear power plant (NPP). This paper presents the analysis of loss of pool cooling accident scenarios and the discussion of mitigation measures for the SFP at a pressurized water reactor (PWR) NPP with the MAAP5 code. Analysis of uncompensated loss of water due to the loss of pool cooling with different initial pool water levels of 12.2 m (designated as a reference case) and 10.7 m have been performed based on a MAAP5 input model. Scenarios of the accident such as overheating of uncovered fuel assemblies, oxidation of claddings and hydrogen generation, loss of intactness of fuel rod claddings, and release of radioactive fission products were predicted with the assumption that mitigation measures were unavailable. The results covered a broad spectrum of severe accident evaluations in the SFP. Furthermore, as important mitigation measures, the effects of recovering the SFP cooling system and makeup water in SFP on the accident progressions have also been investigated respectively based on the events of pool water boiling and spent fuels uncovery. Based upon the reference case, three cases with the recovery of SFP cooling system and three other cases with makeup water in SFP have been studied. The results showed that, severe accident might happen if SFP cooling system was not restored timely before the spent fuels started to become uncovered; spent fuels could be completely submerged and severe accident might be avoided if SFP makeup water system provided water with a mass flow rate larger than the average evaporation rate defined as the division of pool water mass above the

  10. Temperature dependent fission product removal efficiency due to pool scrubbing

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Shunsuke, E-mail: suchida@iae.or.jp [Institute of Applied Energy, 1-14-2, Nishi-Shimbashi, Minato-ku, Tokyo 105-0003 (Japan); Itoh, Ayumi; Naitoh, Masanori; Okada, Hidetoshi; Suzuki, Hiroyuki [Institute of Applied Energy, 1-14-2, Nishi-Shimbashi, Minato-ku, Tokyo 105-0003 (Japan); Hanamoto, Yukio [KAKEN, Inc., 1044, Hori-machi, Mito 310-0903 (Japan); Osakabe, Masahiro [Tokyo University of Marine Science & Technology, Koutou-ku, Tokyo 135-8533 (Japan); Fujikawa, Masahiro [Japan Broadcasting Corporation, 2-2-1, Jinnan, Shibuya-ku, Tokyo 150-8001 (Japan)

    2016-03-15

    Highlights: • Pool temperature effects on the FP removal were not clearly concluded in the previous publications. • It was confirmed that the removal efficiency decreased with temperature around the boiling point. • A modified empirical formula for FP removal was proposed as a function of sub-cooling temperature. • DF could be predicted with an accuracy within a factor of 2 with the proposed formula. - Abstract: The wet-well of boiling water reactors plays important roles not only to suppress the pressure in the primary containment vessel due to steam scrubbing effects during severe accidents but also to mitigate release of radioactive fission products (FP), aerosols and particulates, into the environment. The effects of steam scrubbing in the wet-well on FP removal have been well studied and reported by changing major parameters determining the removal efficiencies, e.g., aerosol diameters, submergence (depth of scrubbing nozzles) and steam/non-condensable gas volume fraction. Unfortunately, the effects of pool temperature on the FP removal were not clearly concluded in the previous publications, though it would be easily expected that boiling in the pool resulted in reduced aerosol removal efficiency. In order to determine the temperature effects on FP removal efficiency, amounts of cesium in aerosols released from scrubbing pool were measured by changing pool temperature in mini and medium scale scrubbing experiments, and then, it was confirmed that the removal efficiency clearly decreased with temperature around the boiling point. Then, a modified empirical formula to express the FP removal around the boiling point temperature was proposed as a function of sub-cooling temperature by applying the effective steam volume fraction, which was designated as the volume ratio of condensed steam in the pool versus the sum of input steam and non-condensable gas. By comparing the measured removal efficiency with the calculated, it was validated that the

  11. The pool chlorine hypothesis and asthma among boys.

    LENUS (Irish Health Repository)

    Cotter, A

    2012-01-31

    Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys. METHODS: The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71\\/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.

  12. Temperature dependent fission product removal efficiency due to pool scrubbing

    International Nuclear Information System (INIS)

    Uchida, Shunsuke; Itoh, Ayumi; Naitoh, Masanori; Okada, Hidetoshi; Suzuki, Hiroyuki; Hanamoto, Yukio; Osakabe, Masahiro; Fujikawa, Masahiro

    2016-01-01

    Highlights: • Pool temperature effects on the FP removal were not clearly concluded in the previous publications. • It was confirmed that the removal efficiency decreased with temperature around the boiling point. • A modified empirical formula for FP removal was proposed as a function of sub-cooling temperature. • DF could be predicted with an accuracy within a factor of 2 with the proposed formula. - Abstract: The wet-well of boiling water reactors plays important roles not only to suppress the pressure in the primary containment vessel due to steam scrubbing effects during severe accidents but also to mitigate release of radioactive fission products (FP), aerosols and particulates, into the environment. The effects of steam scrubbing in the wet-well on FP removal have been well studied and reported by changing major parameters determining the removal efficiencies, e.g., aerosol diameters, submergence (depth of scrubbing nozzles) and steam/non-condensable gas volume fraction. Unfortunately, the effects of pool temperature on the FP removal were not clearly concluded in the previous publications, though it would be easily expected that boiling in the pool resulted in reduced aerosol removal efficiency. In order to determine the temperature effects on FP removal efficiency, amounts of cesium in aerosols released from scrubbing pool were measured by changing pool temperature in mini and medium scale scrubbing experiments, and then, it was confirmed that the removal efficiency clearly decreased with temperature around the boiling point. Then, a modified empirical formula to express the FP removal around the boiling point temperature was proposed as a function of sub-cooling temperature by applying the effective steam volume fraction, which was designated as the volume ratio of condensed steam in the pool versus the sum of input steam and non-condensable gas. By comparing the measured removal efficiency with the calculated, it was validated that the

  13. Sodium-water reaction in double pool LMFBR, (5)

    International Nuclear Information System (INIS)

    Yoshida, Kazuo; Kumagai, Hiromichi; Nishi, Yoshihisa; Uotani, Masaki

    1990-01-01

    Experiments were conducted using a 1/5 scale model of the Double Pool in order to evaluate a pressure rise caused by a large scale sodium-water reaction. The experiments were focused on the pressure rise caused by the piston motion of liquid sodium. It appeared from the results that the magnitude of this pressure rise depends on the depth of reaction point, and that a pressure rise more than 1 MPa would arise in the real Double Pool plant. A new design of steam generator is proposed to mitigate the pressure rise. (author)

  14. The CERN Electronics Pool moves to Building 13

    CERN Multimedia

    PH Department

    2010-01-01

    After 32 years in Building 4 R‐050, the CERN Electronics Pool will re‐open in Building 13 R009 on Monday 13 December at 10:00 As of this date, you will be able to come and choose the instruments you want: oscilloscopes and other measurement instruments, low and high voltage power supplies, modular instrumentation, etc. Please do not hesitate to consult the catalogue and give us any input you may have. The CERN Electronics Pool operates on a self-service basis (with a CERN budget code) and is available for any help you may need.

  15. Carbon dynamics in peatland pool systems: the role of light

    Science.gov (United States)

    Pickard, Amy; Heal, Kate; McLeod, Andy; Dinsmore, Kerry

    2016-04-01

    Open-water pools are widespread in peatlands and are considered to represent biogeochemical hotspots within the peatland landscape. However the contribution of pool systems to wider peatland C cycling has not been quantified fully and there is a lack of knowledge of the role of photochemical processes in such environments. In this study, light exposure experiments were conducted in two contrasting pools to test the reactivity of aquatic C. The first study site was located at Cross Lochs (CL), Forsinard, in the Flow Country of Northern Scotland, in a 412 m2 pool characterised by low dissolved organic carbon (DOC) concentrations (˜15 mg C L-1). The second site was located at Red Moss of Balerno (RM), a raised bog in central Scotland, in a 48 m2 pool with high DOC concentrations (˜35 mg C L-1). Experiments took place over 9 days in situ at each pool in mid-summer 2015, with 500 mL water samples contained in bags transparent to sunlight and in opaque control bags. After field exposure, optical, chemical and stable C isotope analyses were conducted on the samples. Significant differences in biogeochemical cycling of DOC were detected between the two systems, with DOC losses as a percentage of the total C pool 15% higher at RM than at CL after light exposure. The mean DOC concentration of light exposed samples at RM declined steeply initially, with 83% observed DOC degradation occurring by day 3 of the experiment. Total losses of 7.9 mg DOC L-1were observed in light exposed samples at RM, along with decreasing E4:E6 ratios, suggesting that material remaining at the end of the experiment was humified. Depletion of DOC was positively correlated with production of CO2 at both sites, with concentrations of up to 4.3 mg CO2-C L-1 recorded at RM. Stable C isotope signatures at both sites were altered under light treatment, as demonstrated by the production of enriched δ13C-DOC (+0.46 ‰ relative to opaque bags) and depleted δ13C-DIC (-0.97 ‰ relative to opaque bags) at

  16. Software for the Design of Swimming Pool Dehumidifiers Units

    Science.gov (United States)

    Rubina, Aleš; Blasinski, Petr; Tesař, Zdeněk

    2013-06-01

    The article deals with the description and solution of physical phenomena taking place during evaporation of water. The topicality of the theme is given a number of built indoor swimming pool and wellness centers at present. In addressing HVAC systems serving these areas, it is necessary to know the various design parameters in the interior including the water temperature as the pool temperature and humidity. Following is a description of the calculation module, air handling units, including optimizing the settings of the physical changes in order to ensure the lowest energy consumption for air treatment and required maintaining internal microclimate parameters.

  17. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    2008-05-29

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.  Created: 5/29/2008 by Emerging Infectious Diseases.   Date Released: 5/29/2008.

  18. Measure Guideline: Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A.; Easley, S.

    2012-05-01

    The report evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provide a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  19. Measure Guideline. Replacing Single-Speed Pool Pumps with Variable Speed Pumps for Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States); Easley, S. [Building Media and the Building America Retrofit Alliance (BARA), Wilmington, DE (United States)

    2012-05-01

    This measure guideline evaluates potential energy savings by replacing traditional single-speed pool pumps with variable speed pool pumps, and provides a basic cost comparison between continued uses of traditional pumps verses new pumps. A simple step-by-step process for inspecting the pool area and installing a new pool pump follows.

  20. Characteristics of pools used by adult summer steelhead oversummering in the New River, California

    Science.gov (United States)

    Rodney J. Nakamoto

    1994-01-01

    Abstract - I assessed characteristics of pools used by oversummering adults of summer steelhead Oncorhynchus mykiss between July and October 1991 in the New River, northwestern California. Most fish occupied channel confluence pools and other pools of moderate size (200-1,200 m 2); these pools had less than 35% substrate embeddedness and mean water depths of about 1.0...