WorldWideScience

Sample records for subscale model exhaust

  1. Modeling the Gas Dynamics Environment in a Subscale Solid Rocket Test Motor

    Science.gov (United States)

    Eaton, Andrew M.; Ewing, Mark E.; Bailey, Kirk M.; McCool, Alex (Technical Monitor)

    2001-01-01

    Subscale test motors are often used for the evaluation of solid rocket motor component materials such as internal insulation. These motors are useful for characterizing insulation performance behavior, screening insulation material candidates and obtaining material thermal and ablative property design data. One of the primary challenges associated with using subscale motors however, is the uncertainty involved when extrapolating the results to full-scale motor conditions. These uncertainties are related to differences in such phenomena as turbulent flow behavior and boundary layer development, propellant particle interactions with the wall, insulation off-gas mixing and thermochemical reactions with the bulk flow, radiation levels, material response to the local environment, and other anomalous flow conditions. In addition to the need for better understanding of physical mechanisms, there is also a need to better understand how to best simulate these phenomena using numerical modeling approaches such as computational fluid dynamics (CFD). To better understand and model interactions between major phenomena in a subscale test motor, a numerical study of the internal flow environment of a representative motor was performed. Simulation of the environment included not only gas dynamics, but two-phase flow modeling of entrained alumina particles like those found in an aluminized propellant, and offgassing from wall surfaces similar to an ablating insulation material. This work represents a starting point for establishing the internal environment of a subscale test motor using comprehensive modeling techniques, and lays the groundwork for improving the understanding of the applicability of subscale test data to full-scale motors. It was found that grid resolution, and inclusion of phenomena in addition to gas dynamics, such as two-phase and multi-component gas composition are all important factors that can effect the overall flow field predictions.

  2. Development of the Transport Class Model (TCM) Aircraft Simulation From a Sub-Scale Generic Transport Model (GTM) Simulation

    Science.gov (United States)

    Hueschen, Richard M.

    2011-01-01

    A six degree-of-freedom, flat-earth dynamics, non-linear, and non-proprietary aircraft simulation was developed that is representative of a generic mid-sized twin-jet transport aircraft. The simulation was developed from a non-proprietary, publicly available, subscale twin-jet transport aircraft simulation using scaling relationships and a modified aerodynamic database. The simulation has an extended aerodynamics database with aero data outside the normal transport-operating envelope (large angle-of-attack and sideslip values). The simulation has representative transport aircraft surface actuator models with variable rate-limits and generally fixed position limits. The simulation contains a generic 40,000 lb sea level thrust engine model. The engine model is a first order dynamic model with a variable time constant that changes according to simulation conditions. The simulation provides a means for interfacing a flight control system to use the simulation sensor variables and to command the surface actuators and throttle position of the engine model.

  3. PHYSICAL AND NUMERICAL MODELING OF ASD EXHAUST DISPERSION AROUND HOUSES

    Science.gov (United States)

    The report discusses the use of a wind tunnel to physically model the dispersion of exhaust plumes from active soil depressurization (ASD) radon mitigation systems in houses. he testing studied the effects of exhaust location (grade level vs. above the eave), as house height, roo...

  4. Development of a sub-scale dynamics model for pressure relaxation of multi-material cells in Lagrangian hydrodynamics

    Directory of Open Access Journals (Sweden)

    Canfield T.R.

    2011-01-01

    Full Text Available We have extended the Sub-Scale Dynamics (SSD closure model for multi-fluid computational cells. Volume exchange between two materials is based on the interface area and a notional interface translation velocity, which is derived from a linearized Riemann solution. We have extended the model to cells with any number of materials, computing pressure-difference-driven volume and energy exchange as the algebraic sum of pairwise interactions. In multiple dimensions, we rely on interface reconstruction to provide interface areas and orientations, and centroids of material polygons. In order to prevent unphysically large or unmanageably small material volumes, we have used a flux-corrected transport (FCT approach to limit the pressure-driven part of the volume exchange. We describe the implementation of this model in two dimensions in the FLAG hydrodynamics code. We also report on Lagrangian test calculations, comparing them with others made using a mixed-zone closure model due to Tipton, and with corresponding calculations made with only single-material cells. We find that in some cases, the SSD model more accurately predicts the state of material in mixed cells. By comparing the algebraic forms of both models, we identify similar dependencies on state and dynamical variables, and propose explanations for the apparent higher fidelity of the SSD model.

  5. Dale Reed with X-38 and a Subscale Model Used in Test Program

    Science.gov (United States)

    1997-01-01

    Dale Reed, a NASA engineer who worked on the original lifting-body research programs in the 1960s and 1970s, stands with a scale-model X-38 that was used in 1995 research flights, with a full-scale X-38 (80 percent of the size of a potential Crew Return Vehicle) behind him. The X-38 Crew Return Vehicle (CRV) research project is designed to develop the technology for a prototype emergency crew return vehicle, or lifeboat, for the International Space Station. The project is also intended to develop a crew return vehicle design that could be modified for other uses, such as a joint U.S. and international human spacecraft that could be launched on the French Ariane-5 Booster. The X-38 project is using available technology and off-the-shelf equipment to significantly decrease development costs. Original estimates to develop a capsule-type crew return vehicle were estimated at more than $2 billion. X-38 project officials have estimated that development costs for the X-38 concept will be approximately one quarter of the original estimate. Off-the-shelf technology is not necessarily 'old' technology. Many of the technologies being used in the X-38 project have never before been applied to a human-flight spacecraft. For example, the X-38 flight computer is commercial equipment currently used in aircraft and the flight software operating system is a commercial system already in use in many aerospace applications. The video equipment for the X-38 is existing equipment, some of which has already flown on the space shuttle for previous NASA experiments. The X-38's primary navigational equipment, the Inertial Navigation System/Global Positioning System, is a unit already in use on Navy fighters. The X-38 electromechanical actuators come from previous joint NASA, U.S. Air Force, and U.S. Navy research and development projects. Finally, an existing special coating developed by NASA will be used on the X-38 thermal tiles to make them more durable than those used on the space

  6. REVIEW ARTICLE: MODELLING AND ANALYSIS OF A GASOLINE ENGINE EXHAUST GAS SYSTEMS

    OpenAIRE

    Barhm Mohamad

    2018-01-01

    The engine exhaust gas behaviour is strongly influencing the engine performance. This paper presents the modelling and analysis of four stroke - gasoline engine exhaust gas systems. An automotive example is considered whereby the pulsating exhausts gas flow through an exhaust pipe and silencer are considered over a wide range of speeds. Analytical procedures are outlined enabling the general analysis and modelling of vehicle engine exhaust gas systems also in this paper present...

  7. A3 Subscale Diffuser Test Article Design

    Science.gov (United States)

    Saunders, G. P.

    2009-01-01

    This paper gives a detailed description of the design of the A3 Subscale Diffuser Test (SDT) Article Design. The subscale diffuser is a geometrically accurate scale model of the A3 altitude rocket facility. It was designed and built to support the SDT risk mitigation project located at the E3 facility at Stennis Space Center, MS (SSC) supporting the design and construction of the A3 facility at SSC. The subscale test article is outfitted with a large array of instrumentation to support the design verification of the A3 facility. The mechanical design of the subscale diffuser and test instrumentation are described here

  8. Modelling and Operation of Diesel Engine Exhaust Gas Cleaning Systems

    DEFF Research Database (Denmark)

    Åberg, Andreas

    . Challenges with this technology include dosing the appropriate amount of urea to reach sufficient NOx conversion, while at the same time keeping NH3- slip from the exhaust system below the legislation. This requires efficient control algorithms. The focus of this thesis is modelling and control of the SCR...... parameters were estimated using bench-scale monolith isothermal data. Validation was done by simulating the out-put from a full-scale SCR monolith that was treating real engine gases from the European Transient Cycle (ETC). Results showed that the models were successfully calibrated, and that some......, and simulating the system....

  9. A multilayer model to simulate rocket exhaust clouds

    Directory of Open Access Journals (Sweden)

    Davidson Martins Moreira

    2011-01-01

    Full Text Available This paper presents the MSDEF (Modelo Simulador da Dispersão de Efluentes de Foguetes, in Portuguese model, which represents the solution for time-dependent advection-diffusion equation applying the Laplace transform considering the Atmospheric Boundary Layer as a multilayer system. This solution allows a time evolution description of the concentration field emitted from a source during a release lasting time tr , and it takes into account deposition velocity, first-order chemical reaction, gravitational settling, precipitation scavenging, and plume rise effect. This solution is suitable for describing critical events relative to accidental release of toxic, flammable, or explosive substances. A qualitative evaluation of the model to simulate rocket exhaust clouds is showed.

  10. A Nonlinear Dynamic Subscale Model for Partially Resolved Numerical Simulation (PRNS)/Very Large Eddy Simulation (VLES) of Internal Non-Reacting Flows

    Science.gov (United States)

    Shih, Tsan-Hsing; Liu, nan-Suey

    2010-01-01

    A brief introduction of the temporal filter based partially resolved numerical simulation/very large eddy simulation approach (PRNS/VLES) and its distinct features are presented. A nonlinear dynamic subscale model and its advantages over the linear subscale eddy viscosity model are described. In addition, a guideline for conducting a PRNS/VLES simulation is provided. Results are presented for three turbulent internal flows. The first one is the turbulent pipe flow at low and high Reynolds numbers to illustrate the basic features of PRNS/VLES; the second one is the swirling turbulent flow in a LM6000 single injector to further demonstrate the differences in the calculated flow fields resulting from the nonlinear model versus the pure eddy viscosity model; the third one is a more complex turbulent flow generated in a single-element lean direct injection (LDI) combustor, the calculated result has demonstrated that the current PRNS/VLES approach is capable of capturing the dynamically important, unsteady turbulent structures while using a relatively coarse grid.

  11. Experimental and numerical investigation of a simplified exhaust model

    Directory of Open Access Journals (Sweden)

    Balázs Vehovszky

    2016-10-01

    Full Text Available A simplified experimental equipment was built to investigate heat radiation and free convection around hot exhaust pipe. Temperatures were measured on the surface of the pipe as like as on heat insulating and -reflecting aluminum shield. Special care was taken to the temperature measuring method: result proved that inappropriate fixing of measuring thermocouples lead to an error of up to 30 % in the temperature-increase values. A detailed 1D numerical model was set up and parametrized so as to the calculation results can be fitted to measured temperature values. In this way thermal properties of the surfaces – as emissivities, absorption coefficients and convective heat transfer coefficients – were determined for temperature sweeps and stationary state cases. The used methods are to be further improved for real automotive parts and higher temperatures.

  12. Prediction of dynamics of bellows in exhaust system of vehicle using equivalent beam modeling

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Ho; Kim, Yong Dae; Lee, Nam Young; Lee, Sang Woo [Noise and vibration CAE Team, Hyundai Motor Company, Ulsan (Korea, Republic of)

    2015-11-15

    The exhaust system is one of the major sources of vibrations, along with the suspension system and engine. When the exhaust system is connected directly to the engine, it transfers vibrations to the vehicle body through the body mounts. Therefore, in order to reduce the vibrations transmitted from the exhaust system, the vibration characteristics of the exhaust system should be predicted. Thus, the dynamic characteristics of the bellows, which form a key component of the exhaust system, must be modeled accurately. However, it is difficult to model the bellows because of the complicated geometry. Though the equivalent beam modeling technique has been applied in the design stage, it is not sufficiently accurate in the case of the bellows which have complicated geometries. In this paper, we present an improved technique for modeling the bellows in a vehicle. The accuracy of the modeling method is verified by comparison with the experimental results.

  13. A WEAR MODEL FOR DIESEL ENGINE EXHAUST VALVES

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter Julian [ORNL

    2009-11-01

    The work summarized here comprises the concluding effort of a multi-year project, funded by the U.S. Department of Energy, Office of Vehicle Technologies. It supports the development of a better understanding of advanced diesel engine designs in which enhanced power density, energy efficiency, and emissions control place increasing demands upon the durability of engine materials. Many kinds of metallic alloys are used in engines depending on the operating stresses, temperatures, and chemical environments. Exhaust valves, for example, are subjected to high temperatures and repetitive surface contacts that place demands on durability and frictional characteristics of the materials. Valves must continue to seal the combustion chamber properly for thousands of hours of cyclic engine operation and under varying operating conditions. It was the focus of this effort to understand the wear processes in the valve-seat area and to develop a model for the surface deformation and wear of that important interface. An annotated bibliography is provided to illustrate efforts to understand valve wear and to investigate the factors of engine operation that affect its severity and physical manifestation. The project for which this modeling effort was the final task, involved construction of a high-temperature repetitive impact test system as well as basic tribology studies of the combined processes of mechanical wear plus oxidation at elevated temperatures. Several publications resulted from this work, and are cited in this report. The materials selected for the experimental work were high-performance alloys based on nickel and cobalt. In some cases, engine-tested exhaust valves were made available for wear analysis and to ensure that the modes of surface damage produced in experiments were simulative of service. New, production-grade exhaust valves were also used to prepare test specimens for experimental work along with the other alloy samples. Wear analysis of valves and seats

  14. Thermodynamic control-oriented modeling of cycle-to-cycle exhaust gas temperature in an HCCI engine

    International Nuclear Information System (INIS)

    Dehghani Firoozabadi, M.; Shahbakhti, M.; Koch, C.R.; Jazayeri, S.A.

    2013-01-01

    Highlights: • First thermodynamic model in the literature to predict exhaust temperature in HCCI engines. • The model can be used for integrated control of HCCI combustion and exhaust temperature. • The model is experimentally validated at over 300 steady state and transient conditions. • Results show a good agreement between predicted and measured exhaust temperatures. • Sensitivity of exhaust gas temperature to variation of engine variables is shown. - Abstract: Model-based control of Homogenous Charge Compression Ignition (HCCI) engine exhaust temperature is a viable solution to optimize efficiency of both engine and the exhaust aftertreatment system. Low exhaust temperature in HCCI engines can limit the abatement of hydrocarbon (HC) and carbon monoxide (CO) emissions in an exhaust aftertreatment system. A physical–empirical model is described for control of exhaust temperature in HCCI engines. This model captures cycle-to-cycle dynamics affecting exhaust temperature and is based on thermodynamic relations and semi-empirical correlations. It incorporates intake and exhaust gas flow dynamics, residual gas mixing, and fuel burn rate and is validated with experimental data from a single cylinder engine at over 300 steady state and transient conditions. The validation results indicate a good agreement between predicted and measured exhaust gas temperature

  15. Validated analytical modeling of diesel engine regulated exhaust CO emission rate

    Directory of Open Access Journals (Sweden)

    Waleed F Faris

    2016-06-01

    Full Text Available Albeit vehicle analytical models are often favorable for explainable mathematical trends, no analytical model has been developed of the regulated diesel exhaust CO emission rate for trucks yet. This research unprecedentedly develops and validates for trucks a model of the steady speed regulated diesel exhaust CO emission rate analytically. It has been found that the steady speed–based CO exhaust emission rate is based on (1 CO2 dissociation, (2 the water–gas shift reaction, and (3 the incomplete combustion of hydrocarbon. It has been found as well that the steady speed–based CO exhaust emission rate based on CO2 dissociation is considerably less than the rate that is based on the water–gas shift reaction. It has also been found that the steady speed–based CO exhaust emission rate based on the water–gas shift reaction is the dominant source of CO exhaust emission. The study shows that the average percentage of deviation of the steady speed–based simulated results from the corresponding field data is 1.7% for all freeway cycles with 99% coefficient of determination at the confidence level of 95%. This deviation of the simulated results from field data outperforms its counterpart of widely recognized models such as the comprehensive modal emissions model and VT-Micro for all freeway cycles.

  16. Mediating effects of emotional exhaustion on the relationship between job demand–control model and mental health.

    Science.gov (United States)

    Huang, Yu-Hwa; Du, Pey-Ian; Chen, Chin-Hui; Yang, Chin-Ann; Huang, Ing-Chung

    2011-04-01

    This study attempted to investigate the role of emotional exhaustion as a mediator on the relationship between job demands-control (JDC) model and mental health. Three-wave data from 297 employees were collected. The results showed that job demands were positively related to emotional exhaustion, and increasing job demands will increase the level of emotional exhaustion. Job control was negatively associated with emotional exhaustion; therefore, increasing job control will decrease the level of emotional exhaustion. Emotional exhaustion was negatively related to mental health. Emotional exhaustion fully mediated the relationship between job demands and mental health, and partially mediated the positive relationship between job control and mental health. In addition, job control was positively associated with mental health directly. The remarkable finding of the present study was that emotional exhaustion served as the key mediator between the JDC model and mental health. Theoretical and managerial implications and limitations were discussed.

  17. Heat transfer modeling in exhaust systems of high-performance two-stroke engines

    OpenAIRE

    Lujan Martinez, José Manuel; Climent Puchades, Héctor; Olmeda González, Pablo Cesar; JIMENEZ MACEDO, VICTOR DANIEL

    2014-01-01

    Heat transfer from the hot gases to the wall in exhaust systems of high-performance two-stroke engines is underestimated using steady state with fully developed flow empirical correlations. This fact is detected when comparing measured and modeled pressure pulses in different positions in the exhaust system. This can be explained taking into account that classical expressions have been validated for fully developed flows, a situation that is far from the flow behavior in reciprocating interna...

  18. A Framework for Modular Modeling of the Diesel Engine Exhaust Gas Cleaning System

    DEFF Research Database (Denmark)

    Åberg, Andreas; Hansen, Thomas Klint; Linde, Kasper

    2015-01-01

    Pollutants from diesel engines have a negative effect on urban air quality. Because of this and new legislation restricting the emission level, it is necessary to develop exhaust gas treatment systems for diesel engines that can reduce the amount of pollutants. A modular model capable of simulating...... model. Four different models in the automotive diesel exhaust gas cleaning system are presented briefly. Based on the presented methodology, it is discussed which changes are needed to the models to create a modular model of the whole catalytic system....

  19. CONCEPT AND MODELS FOR EVALUATION OF BLACK AND WHITE SMOKE COMPONENTS IN DIESEL ENGINE EXHAUST

    Directory of Open Access Journals (Sweden)

    Igor BLYANKINSHTEIN

    2017-09-01

    Full Text Available A method for measuring exhaust smoke opacity has been developed, which allows estimating the differentiated components forming black exhaust and those forming white smoke. The method is based on video recording and special software for processing the video recording data. The flow of the diesel exhaust gas is visualised using the digital camera, against the background of the screen, on a cut of an exhaust pipe, and with sufficient illumination of the area. The screen represents standards of whiteness and blackness. The content of the black components (soot is determined by the degree of blackening of the white standard in the frames of the video, and the content of whitish components (unburned fuel and oil, etc. is determined by the degree of whitening of black standard on the frames of the video. The paper describes the principle and the results of testing the proposed method of measuring exhaust smoke opacity. We present an algorithm for the frame-by-frame analysis of the video sequence, and static and dynamic mathematical models of exhaust opacity, measured under free-acceleration of a diesel engine.

  20. New Model Exhaust System Supports Testing in NASA Lewis' 10- by 10-Foot Supersonic Wind Tunnel

    Science.gov (United States)

    Roeder, James W., Jr.

    1998-01-01

    In early 1996, the ability to run NASA Lewis Research Center's Abe Silverstein 10- by 10- Foot Supersonic Wind Tunnel (10x10) at subsonic test section speeds was reestablished. Taking advantage of this new speed range, a subsonic research test program was scheduled for the 10x10 in the fall of 1996. However, many subsonic aircraft test models require an exhaust source to simulate main engine flow, engine bleed flows, and other phenomena. This was also true of the proposed test model, but at the time the 10x10 did not have a model exhaust capability. So, through an in-house effort over a period of only 5 months, a new model exhaust system was designed, installed, checked out, and made ready in time to support the scheduled test program.

  1. A Mathematical Model for the Exhaust Gas Temperature Profile of a Diesel Engine

    Science.gov (United States)

    Brito, C. H. G.; Maia, C. B.; Sodré, J. R.

    2015-09-01

    This work presents a heat transfer model for the exhaust gas of a diesel power generator to determine the gas temperature profile in the exhaust pipe. The numerical methodology to solve the mathematical model was developed using a finite difference method approach for energy equation resolution and determination of temperature profiles considering turbulent fluid flow and variable fluid properties. The simulation was carried out for engine operation under loads from 0 kW to 40 kW. The model was compared with results obtained using the multidimensional Ansys CFX software, which was applied to solve the governor equations of turbulent fluid flow. The results for the temperature profiles in the exhaust pipe show a good proximity between the mathematical model developed and the multidimensional software.

  2. A Study on the Model of Traffic Flow and Vehicle Exhaust Emission

    Directory of Open Access Journals (Sweden)

    Han Xue

    2013-01-01

    Full Text Available The increase of traffic flow in cities causes traffic congestion and accidents as well as air pollution. Traffic problems have attracted the interest of many researchers from the perspective of theory and engineering. In order to provide a simple and practical method for measuring the exhaust emission and assessing the effect of pollution control, a model is based on the relationship between traffic flow and vehicle exhaust emission under a certain level of road capacity constraints. In the proposed model, the hydrocarbons (HC, carbon monoxide (CO, and nitrogen oxides (NOx are considered as the indexes of total exhaust emission, and the speed is used as an intermediate variable. To verify the rationality and practicality of the model, a case study for Beijing, China, is provided in which the effects of taxi fare regulation and the specific vehicle emission reduction policy are analyzed.

  3. Assessing Exhaustiveness of Stochastic Sampling for Integrative Modeling of Macromolecular Structures.

    Science.gov (United States)

    Viswanath, Shruthi; Chemmama, Ilan E; Cimermancic, Peter; Sali, Andrej

    2017-12-05

    Modeling of macromolecular structures involves structural sampling guided by a scoring function, resulting in an ensemble of good-scoring models. By necessity, the sampling is often stochastic, and must be exhaustive at a precision sufficient for accurate modeling and assessment of model uncertainty. Therefore, the very first step in analyzing the ensemble is an estimation of the highest precision at which the sampling is exhaustive. Here, we present an objective and automated method for this task. As a proxy for sampling exhaustiveness, we evaluate whether two independently and stochastically generated sets of models are sufficiently similar. The protocol includes testing 1) convergence of the model score, 2) whether model scores for the two samples were drawn from the same parent distribution, 3) whether each structural cluster includes models from each sample proportionally to its size, and 4) whether there is sufficient structural similarity between the two model samples in each cluster. The evaluation also provides the sampling precision, defined as the smallest clustering threshold that satisfies the third, most stringent test. We validate the protocol with the aid of enumerated good-scoring models for five illustrative cases of binary protein complexes. Passing the proposed four tests is necessary, but not sufficient for thorough sampling. The protocol is general in nature and can be applied to the stochastic sampling of any set of models, not just structural models. In addition, the tests can be used to stop stochastic sampling as soon as exhaustiveness at desired precision is reached, thereby improving sampling efficiency; they may also help in selecting a model representation that is sufficiently detailed to be informative, yet also sufficiently coarse for sampling to be exhaustive. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  4. Numerical modelling of the internal mixing by coagulation of black carbon particles in aircraft exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Ohlsson, S.; Stroem, J. [Stockholm Univ. (Sweden). Dept. of Meteorology

    1997-12-31

    When exhaust gases from an aircraft engine mix with ambient air the humidity may reach water saturation and water droplets will form on the available cloud condensation nuclei (CCN). It is still not resolved if the CCN, on which the cloud droplets form, are mainly particles present in the ambient air or particles emitted by the aircraft. It the exhaust from a jet engine the particles are believed to consist mainly of black carbon (BC) and sulfate. The aim is to study, with the help of a numerical model, how a two-component aerosol (i.e. BC and sulfate) in an exhaust trail may be transformed in terms of hygroscopicity by coagulation mixing and how this may depend on the sulfur content in the fuel. (R.P.) 15 refs.

  5. Numerical modelling of the internal mixing by coagulation of black carbon particles in aircraft exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Ohlsson, S; Stroem, J [Stockholm Univ. (Sweden). Dept. of Meteorology

    1998-12-31

    When exhaust gases from an aircraft engine mix with ambient air the humidity may reach water saturation and water droplets will form on the available cloud condensation nuclei (CCN). It is still not resolved if the CCN, on which the cloud droplets form, are mainly particles present in the ambient air or particles emitted by the aircraft. It the exhaust from a jet engine the particles are believed to consist mainly of black carbon (BC) and sulfate. The aim is to study, with the help of a numerical model, how a two-component aerosol (i.e. BC and sulfate) in an exhaust trail may be transformed in terms of hygroscopicity by coagulation mixing and how this may depend on the sulfur content in the fuel. (R.P.) 15 refs.

  6. Heavy-traffic limits for polling models with exhaustive service and non-FCFS service orders

    NARCIS (Netherlands)

    P. Vis (Petra); R. Bekker (Rene); R.D. van der Mei (Rob)

    2015-01-01

    htmlabstractWe study cyclic polling models with exhaustive service at each queue under a variety of non-FCFS (first-come-first-served) local service orders, namely last-come-first-served with and without preemption, random-order-of-service, processor sharing, the multi-class priority scheduling with

  7. Fluid dynamic modeling of junctions in internal combustion engine inlet and exhaust systems

    Science.gov (United States)

    Chalet, David; Chesse, Pascal

    2010-10-01

    The modeling of inlet and exhaust systems of internal combustion engine is very important in order to evaluate the engine performance. This paper presents new pressure losses models which can be included in a one dimensional engine simulation code. In a first part, a CFD analysis is made in order to show the importance of the density in the modeling approach. Then, the CFD code is used, as a numerical test bench, for the pressure losses models development. These coefficients depend on the geometrical characteristics of the junction and an experimental validation is made with the use of a shock tube test bench. All the models are then included in the engine simulation code of the laboratory. The numerical calculation of unsteady compressible flow, in each pipe of the inlet and exhaust systems, is made and the calculated engine torque is compared with experimental measurements.

  8. Modified pressure loss model for T-junctions of engine exhaust manifold

    Science.gov (United States)

    Wang, Wenhui; Lu, Xiaolu; Cui, Yi; Deng, Kangyao

    2014-11-01

    The T-junction model of engine exhaust manifolds significantly influences the simulation precision of the pressure wave and mass flow rate in the intake and exhaust manifolds of diesel engines. Current studies have focused on constant pressure models, constant static pressure models and pressure loss models. However, low model precision is a common disadvantage when simulating engine exhaust manifolds, particularly for turbocharged systems. To study the performance of junction flow, a cold wind tunnel experiment with high velocities at the junction of a diesel exhaust manifold is performed, and the variation in the pressure loss in the T-junction under different flow conditions is obtained. Despite the trend of the calculated total pressure loss coefficient, which is obtained by using the original pressure loss model and is the same as that obtained from the experimental results, large differences exist between the calculated and experimental values. Furthermore, the deviation becomes larger as the flow velocity increases. By improving the Vazsonyi formula considering the flow velocity and introducing the distribution function, a modified pressure loss model is established, which is suitable for a higher velocity range. Then, the new model is adopted to solve one-dimensional, unsteady flow in a D6114 turbocharged diesel engine. The calculated values are compared with the measured data, and the result shows that the simulation accuracy of the pressure wave before the turbine is improved by 4.3% with the modified pressure loss model because gas compressibility is considered when the flow velocities are high. The research results provide valuable information for further junction flow research, particularly the correction of the boundary condition in one-dimensional simulation models.

  9. Modeling of aircraft exhaust emissions and infrared spectra for remote measurement of nitrogen oxides

    Directory of Open Access Journals (Sweden)

    K. Beier

    Full Text Available Infrared (IR molecular spectroscopy is proposed to perform remote measurements of NOx concentrations in the exhaust plume and wake of aircraft. The computer model NIRATAM is applied to simulate the physical and chemical properties of the exhaust plume and to generate low resolution IR spectra and synthetical thermal images of the aircraft in its natural surroundings. High-resolution IR spectra of the plume, including atmospheric absorption and emission, are simulated using the molecular line-by-line radiation model FASCODE2. Simulated IR spectra of a Boeing 747-400 at cruising altitude for different axial and radial positions in the jet region of the exhaust plume are presented. A number of spectral lines of NO can be identified that can be discriminated from lines of other exhaust gases and the natural atmospheric background in the region around 5.2 µm. These lines can be used to determine NO concentration profiles in the plume. The possibility of measuring nitrogen dioxide NO2 is also discussed briefly, although measurements turn out to be substantially less likely than those of NO. This feasibility study compiles fundamental data for the optical and radiometric design of an airborne Fourier transform spectrometer and the preparation of in-flight measurements for monitoring of aircraft pollutants.

  10. Modeling of aircraft exhaust emissions and infrared spectra for remote measurement of nitrogen oxides

    Directory of Open Access Journals (Sweden)

    K. Beier

    1994-08-01

    Full Text Available Infrared (IR molecular spectroscopy is proposed to perform remote measurements of NOx concentrations in the exhaust plume and wake of aircraft. The computer model NIRATAM is applied to simulate the physical and chemical properties of the exhaust plume and to generate low resolution IR spectra and synthetical thermal images of the aircraft in its natural surroundings. High-resolution IR spectra of the plume, including atmospheric absorption and emission, are simulated using the molecular line-by-line radiation model FASCODE2. Simulated IR spectra of a Boeing 747-400 at cruising altitude for different axial and radial positions in the jet region of the exhaust plume are presented. A number of spectral lines of NO can be identified that can be discriminated from lines of other exhaust gases and the natural atmospheric background in the region around 5.2 µm. These lines can be used to determine NO concentration profiles in the plume. The possibility of measuring nitrogen dioxide NO2 is also discussed briefly, although measurements turn out to be substantially less likely than those of NO. This feasibility study compiles fundamental data for the optical and radiometric design of an airborne Fourier transform spectrometer and the preparation of in-flight measurements for monitoring of aircraft pollutants.

  11. Accounting for exhaust gas transport dynamics in instantaneous emission models via smooth transition regression.

    Science.gov (United States)

    Kamarianakis, Yiannis; Gao, H Oliver

    2010-02-15

    Collecting and analyzing high frequency emission measurements has become very usual during the past decade as significantly more information with respect to formation conditions can be collected than from regulated bag measurements. A challenging issue for researchers is the accurate time-alignment between tailpipe measurements and engine operating variables. An alignment procedure should take into account both the reaction time of the analyzers and the dynamics of gas transport in the exhaust and measurement systems. This paper discusses a statistical modeling framework that compensates for variable exhaust transport delay while relating tailpipe measurements with engine operating covariates. Specifically it is shown that some variants of the smooth transition regression model allow for transport delays that vary smoothly as functions of the exhaust flow rate. These functions are characterized by a pair of coefficients that can be estimated via a least-squares procedure. The proposed models can be adapted to encompass inherent nonlinearities that were implicit in previous instantaneous emissions modeling efforts. This article describes the methodology and presents an illustrative application which uses data collected from a diesel bus under real-world driving conditions.

  12. Sustainable economic growth and exhaustible resources: A model and estimation for the US

    Directory of Open Access Journals (Sweden)

    Almuth Scholl

    2002-01-01

    Full Text Available This paper studies current models on sustainable economic growth with resource constraints and explores to what extent resource constraints can be overcome by substitution and technological change. We also study the problem of intergenerational equity and the different criteria that have been suggested in the literature. The central part of this paper is the presentation of stylized facts on exhaustible resources and an estimation of a basic model with resource constraints for US time series data. The estimated years left until depletion and the empirical trends of the ratios of capital stock and consumption to resources seem to indicate that there might be a threat to sustainable growth in the future. In our estimation, we obtain parameter values, which help to interpret the extent to which growth with exhaustible resources is sustainable.

  13. Modelling for Control of Exhaust Gas Recirculation on Large Diesel Engines

    DEFF Research Database (Denmark)

    Hansen, Jakob Mahler; Zander, Claes-Göran; Pedersen, Nicolai

    2013-01-01

    Exhaust Gas Recirculation (EGR) reduces NOx emissions by reducing O2 concentration for the combustion and is a preferred way to obtain emission regulations that will take effect from 2016. If not properly controlled, reduction of O2 has adverse side eects and proper control requires proper dynami...... principles followed by parameter identication and compares the results of these approaches. The paper performs a validation against experimental data from a test engine and presents a linearised model for EGR control design....

  14. Model analysis of the chemical conversion of exhaust species in the expanding plumes of subsonic aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Moellhoff, M.; Hendricks, J.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie; Sausen, R. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    A box model and two different one-dimensional models are used to investigate the chemical conversion of exhaust species in the dispersing plume of a subsonic aircraft flying at cruise altitude. The effect of varying daytime of release as well as the impact of changing dispersion time is studied with special respect to the aircraft induced O{sub 3} production. Effective emission amounts for consideration in mesoscale and global models are calculated. Simulations with modified photolysis rates are performed to show the sensitivity of the photochemistry to the occurrence of cirrus clouds. (author) 8 refs.

  15. Potential transformation of trace species including aircraft exhaust in a cloud environment. The `Chedrom model`

    Energy Technology Data Exchange (ETDEWEB)

    Ozolin, Y.E.; Karol, I.L. [Main Geophysical Observatory, St. Petersburg (Russian Federation); Ramaroson, R. [Office National d`Etudes et de Recherches Aerospatiales (ONERA), 92 - Chatillon (France)

    1997-12-31

    Box model for coupled gaseous and aqueous phases is used for sensitivity study of potential transformation of trace gases in a cloud environment. The rate of this transformation decreases with decreasing of pH in droplets, with decreasing of photodissociation rates inside the cloud and with increasing of the droplet size. Model calculations show the potential formation of H{sub 2}O{sub 2} in aqueous phase and transformation of gaseous HNO{sub 3} into NO{sub x} in a cloud. This model is applied for exploration of aircraft exhausts evolution in plume inside a cloud. (author) 10 refs.

  16. Potential transformation of trace species including aircraft exhaust in a cloud environment. The `Chedrom model`

    Energy Technology Data Exchange (ETDEWEB)

    Ozolin, Y E; Karol, I L [Main Geophysical Observatory, St. Petersburg (Russian Federation); Ramaroson, R [Office National d` Etudes et de Recherches Aerospatiales (ONERA), 92 - Chatillon (France)

    1998-12-31

    Box model for coupled gaseous and aqueous phases is used for sensitivity study of potential transformation of trace gases in a cloud environment. The rate of this transformation decreases with decreasing of pH in droplets, with decreasing of photodissociation rates inside the cloud and with increasing of the droplet size. Model calculations show the potential formation of H{sub 2}O{sub 2} in aqueous phase and transformation of gaseous HNO{sub 3} into NO{sub x} in a cloud. This model is applied for exploration of aircraft exhausts evolution in plume inside a cloud. (author) 10 refs.

  17. Model analysis of the chemical conversion of exhaust species in the expanding plumes of subsonic aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Moellhoff, M; Hendricks, J; Lippert, E; Petry, H [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie; Sausen, R [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1998-12-31

    A box model and two different one-dimensional models are used to investigate the chemical conversion of exhaust species in the dispersing plume of a subsonic aircraft flying at cruise altitude. The effect of varying daytime of release as well as the impact of changing dispersion time is studied with special respect to the aircraft induced O{sub 3} production. Effective emission amounts for consideration in mesoscale and global models are calculated. Simulations with modified photolysis rates are performed to show the sensitivity of the photochemistry to the occurrence of cirrus clouds. (author) 8 refs.

  18. Exhaust gas recirculation – Zero dimensional modelling and characterization for transient diesel combustion control

    International Nuclear Information System (INIS)

    Asad, Usman; Tjong, Jimi; Zheng, Ming

    2014-01-01

    Highlights: • Zero-dimensional EGR model for transient diesel combustion control. • Detailed analysis of EGR effects on intake, cylinder charge and exhaust properties. • Intake oxygen validated as an operating condition-independent measure of EGR. • Quantified EGR effectiveness in terms of NOx emission reduction. • Twin lambda sensor technique for estimation of EGR/in-cylinder parameters. - Abstract: The application of exhaust gas recirculation (EGR) during transient engine operation is a challenging task since small fluctuations in EGR may cause larger than acceptable spikes in NOx/soot emissions or deterioration in the combustion efficiency. Moreover, the intake charge dilution at any EGR ratio is a function of engine load and intake pressure, and typically changes during transient events. Therefore, the management of EGR during transient engine operation or advanced combustion cycles (that are inherently less stable) requires a fundamental understanding of the transient EGR behaviour and its impact on the intake charge development. In this work, a zero-dimensional EGR model is described to estimate the transient (cycle-by-cycle) progression of EGR and the time (engine cycles) required for its stabilization. The model response is tuned to a multi-cylinder engine by using an overall engine system time-constant and shown to effectively track the transient EGR changes. The impact of EGR on the actual air–fuel ratio of the cylinder charge is quantified by defining an in-cylinder excess-air ratio that accounts for the oxygen in the recycled exhaust gas. Furthermore, a twin lambda sensor (TLS) technique is implemented for tracking the intake dilution and in-cylinder excess-air ratio in real-time. The modelling and analysis results are validated against a wide range of engine operations, including transient and steady-state low temperature combustion tests

  19. Exhaustively characterizing feasible logic models of a signaling network using Answer Set Programming.

    Science.gov (United States)

    Guziolowski, Carito; Videla, Santiago; Eduati, Federica; Thiele, Sven; Cokelaer, Thomas; Siegel, Anne; Saez-Rodriguez, Julio

    2013-09-15

    Logic modeling is a useful tool to study signal transduction across multiple pathways. Logic models can be generated by training a network containing the prior knowledge to phospho-proteomics data. The training can be performed using stochastic optimization procedures, but these are unable to guarantee a global optima or to report the complete family of feasible models. This, however, is essential to provide precise insight in the mechanisms underlaying signal transduction and generate reliable predictions. We propose the use of Answer Set Programming to explore exhaustively the space of feasible logic models. Toward this end, we have developed caspo, an open-source Python package that provides a powerful platform to learn and characterize logic models by leveraging the rich modeling language and solving technologies of Answer Set Programming. We illustrate the usefulness of caspo by revisiting a model of pro-growth and inflammatory pathways in liver cells. We show that, if experimental error is taken into account, there are thousands (11 700) of models compatible with the data. Despite the large number, we can extract structural features from the models, such as links that are always (or never) present or modules that appear in a mutual exclusive fashion. To further characterize this family of models, we investigate the input-output behavior of the models. We find 91 behaviors across the 11 700 models and we suggest new experiments to discriminate among them. Our results underscore the importance of characterizing in a global and exhaustive manner the family of feasible models, with important implications for experimental design. caspo is freely available for download (license GPLv3) and as a web service at http://caspo.genouest.org/. Supplementary materials are available at Bioinformatics online. santiago.videla@irisa.fr.

  20. A MATHEMATICAL MODEL OF THERMAL POWER PLANTS SMOKE EXHAUSTERS INDUCTION MOTORS SYSTEM OPERATION MODES

    Directory of Open Access Journals (Sweden)

    K. M. Vasyliv

    2017-06-01

    Full Text Available Purpose. Development of a model-software complex (MSC for computer analysis of modes of the system of induction motors (IM of smoke exhausters of thermal power plant (TPP, the basic elements of which are mathematical models and corresponding software written in the programming language FORTRAN. Methodology. Mathematical model serves as a system of differential equations of electrical and mechanical condition. The equation of electric state is written in phase coordinates based on Kirchhoff's laws, and mechanical condition described by the d'Alembert equation. Mathematical model focuses on explicit numerical integration methods. Scientific novelty. The equation of state of electrical connections takes into account the mutual electromagnetic circuits for transformer of own needs (TON and induction motors and interdependence (in all possible combinations between: TON (from which motors powered and each of the two IM and blood pressure between themselves. The complex allows to simulate electromagnetic and electromechanical processes in transitional and steady, symmetric and asymmetric modes including modes of self-induction motors. Results. Complex is used for computer analysis of electromagnetic and electromechanical processes and established the basic laws of motion modes of starting, stopping and self-start of IM of smoke exhausters of the TPP unit. Practical value. The complex is suitable for computer analysis of modes of other similar units of own needs of thermal power plants.

  1. Steady-state modelling of the universal exhaust gas oxygen (UEGO) sensor

    International Nuclear Information System (INIS)

    Collings, N; Hegarty, K; Ramsander, T

    2012-01-01

    The universal exhaust gas oxygen (UEGO) sensor is a well-established device which was developed for the measurement of relative air fuel ratio in internal combustion engines. There is, however, little information available which allows for the prediction of the UEGO's behaviour when exposed to arbitrary gas mixtures, pressures and temperatures. Here we present a steady-state model for the sensor, based on a solution of the Stefan–Maxwell equation, and which includes a momentum balance. The response of the sensor is dominated by a diffusion barrier, which controls the rate of diffusion of gas species between the exhaust and a cavity. Determination of the diffusion barrier characteristics, especially the mean pore size, porosity and tortuosity, is essential for the purposes of modelling, and a measurement technique based on identification of the sensor pressure giving zero temperature sensitivity is shown to be a convenient method of achieving this. The model, suitably calibrated, is shown to make good predictions of sensor behaviour for large variations of pressure, temperature and gas composition. (paper)

  2. Dynamic consistency of leader/fringe models of exhaustible resource markets

    International Nuclear Information System (INIS)

    Pelot, R.P.

    1990-01-01

    A dynamic feedback pricing model is developed for a leader/fringe supply market of exhaustible resources. The discrete game optimization model includes marginal costs which may be quadratic functions of cumulative production, a linear demand curve and variable length periods. The multiperiod formulation is based on the nesting of later periods' Kuhn-Tucker conditions into earlier periods' optimizations. This procedure leads to dynamically consistent solutions where the leader's strategy is credible as he has no incentive to alter his original plan at some later stage. A static leader-fringe model may yield multiple local optima. This can result in the leader forcing the fringe to produce at their capacity constraint, which would otherwise be non-binding if it is greater than the fringe's unconstrained optimal production rate. Conditions are developed where the optimal solution occurs at a corner where constraints meet, of which limit pricing is a special case. The 2-period leader/fringe feedback model is compared to the computationally simpler open-loop model. Under certain conditions, the open-loop model yields the same result as the feedback model. A multiperiod feedback model of the world oil market with OPEC as price-leader and the remaining world oil suppliers comprising the fringe is compared with the open-loop solution. The optimal profits and prices are very similar, but large differences in production rates may occur. The exhaustion date predicted by the open-loop model may also differ from the feedback outcome. Some numerical tests result in non-contiguous production periods for a player or limit pricing phases. 85 refs., 60 figs., 30 tabs

  3. Local Exhaust Ventilation

    DEFF Research Database (Denmark)

    Madsen, Ulla; Breum, N. O.; Nielsen, Peter V.

    Capture efficiency of a local exhaust system, e.g. a kitchen hood, should include only contaminants being direct captured. In this study basic concepts of local exhaust capture efficiency are given, based on the idea of a control box. A validated numerical model is used for estimation of the capt......Capture efficiency of a local exhaust system, e.g. a kitchen hood, should include only contaminants being direct captured. In this study basic concepts of local exhaust capture efficiency are given, based on the idea of a control box. A validated numerical model is used for estimation...

  4. Work-life balance culture, work-home interaction, and emotional exhaustion: a structural equation modeling approach.

    Science.gov (United States)

    Nitzsche, Anika; Pfaff, Holger; Jung, Julia; Driller, Elke

    2013-01-01

    To examine the relationships among employees' emotional exhaustion, positive and negative work-home interaction, and perceived work-life balance culture in companies. Data for this study were collected through online surveys of employees from companies in the micro- and nanotechnology sectors (N = 509). A structural equation modeling analysis was performed. A company culture perceived by employees as supportive of their work-life balance was found to have both a direct negative effect on emotional exhaustion and an indirect negative effect meditated by negative work-home interaction. In addition, whereas negative work-home interaction associated positively with emotional exhaustion, positive work-home interaction had no significant effect. The direct and indirect relationship between work-life balance culture and emotional exhaustion has practical implications for health promotion in companies.

  5. Developing Computational Fluid Dynamics (CFD Models to Evaluate Available Energy in Exhaust Systems of Diesel Light-Duty Vehicles

    Directory of Open Access Journals (Sweden)

    Pablo Fernández-Yáñez

    2017-06-01

    Full Text Available Around a third of the energy input in an automotive engine is wasted through the exhaust system. Since numerous technologies to harvest energy from exhaust gases are accessible, it is of great interest to find time- and cost-efficient methods to evaluate available thermal energy under different engine conditions. Computational fluid dynamics (CFD is becoming a very valuable tool for numerical predictions of exhaust flows. In this work, a methodology to build a simple three-dimensional (3D model of the exhaust system of automotive internal combustion engines (ICE was developed. Experimental data of exhaust gas in the most used part of the engine map in passenger diesel vehicles were employed as input for calculations. Sensitivity analyses of different numeric schemes have been conducted in order to attain accurate results. The model built allows for obtaining details on temperature and pressure fields along the exhaust system, and for complementing the experimental results for a better understanding of the flow phenomena and heat transfer through the system for further energy recovery devices.

  6. Plasma exhaust purification by thermal swing adsorption: Experimental results and modeling

    International Nuclear Information System (INIS)

    Ricapito, I.; Malara, R.C.

    1996-01-01

    For several years at the Joint Research Centre-Ispra laboratories, cyclic adsorption processes have been developed for the purification of the plasma exhaust stream of a deuterium-tritium fusion reactor. A purification process consisting of two coupled thermal swing adsorption systems seemed to be the most convenient process. In this context, a screening study was carried out to select the most suitable adsorbent materials and appropriate working temperatures. This was mainly done by experimental measurements of adsorption isotherms of the single components of the plasma exhaust stream and by a careful evaluation of the multicomponent adsorption equilibria. Experiments on adsorption dynamics were carried out in a pilot plant to demonstrate the feasibility and to evaluate the performance of the process. The experimental apparatus was designed to treat gas mixture flow rates up to 20 to 30 standard temperature and pressure l/h. A mathematical model was developed and tested against the experimental results to describe the adsorption process and, in particular, to evaluate and to optimize the process cycle time. 27 refs., 4 figs., 9 tabs

  7. Identification of black-box linear models : the case of thermal periodic contact of exhaust valves in internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Shojaeefard, M.H.; Fazelpour, M. [Iran Univ. of Science and Technology, Tehran (Iran, Islamic Republic of). Dept. of Automotive Engineering; Goudarzi, K. [Iran Univ. of Science and Technology, Tehran (Iran, Islamic Republic of). Dept. of Mechanical Engineering

    2009-07-01

    In internal combustion engines, hot exhaust gases that pass through the exhaust valve lead to high temperatures in the exhaust valve and the valve seat. Heat must be transferred from the exhaust valve to valve seat as they come in contact with each other during the opening and closing cycle in order to avoid damaging the exhaust valve. The heat transfer rate from the valve to valve seat is a function of many factors, including the thermal contact conductance (TCC) between the valve and valve seat. The objective of this study was to experimentally calculate the TCC for six different frequencies in the quasi-steady-state condition and also to obtain a transfer function to estimate the exhaust valve temperature by using black-box models of system identification. Periodic contact was taken into consideration in the study. The paper presented the experimental setup including the loading system, heat and cooling system, temperature measurement system, specimens properties, and data acquisition system. The paper also described the test procedure and experimental results. System identification was also described. It was concluded that the TCC decreased as the frequency of contact increased. The temperature transfer function was calculated by using the system identification method and having the temperatures at both sides of the contact surface. By knowing the temperature of one rod, the temperature of the other rod was estimated with high accuracy. 16 refs., 4 tabs., 7 figs.

  8. Modeling and optimization of integrated exhaust gas recirculation and multi-stage waste heat recovery in marine engines

    DEFF Research Database (Denmark)

    Kyriakidis, Fotis; Sørensen, Kim; Singh, Shobhana

    2017-01-01

    Waste heat recovery combined with exhaust gas recirculation is a promising technology that can address both the issue of NOx (nitrogen oxides) reduction and fuel savings by including a pressurized boiler. In the present study, a theoretical optimization of the performance of two different...... configurations of steam Rankine cycles, with integrated exhaust gas recirculation for a marine diesel engine, is presented. The first configuration employs two pressure levels and the second is configured with three-pressure levels. The models are developed in MATLAB based on the typical data of a large two......-stroke marine diesel engine. A turbocharger model together with a blower, a pre-scrubber and a cooler for the exhaust gas recirculation line, are included. The steam turbine, depending on the configuration, is modeled as either a dual or triple pressure level turbine. The condensation and pre-heating process...

  9. Vehicle Exhaust Waste Heat Recovery Model with Integrated Thermal Load Leveling

    Science.gov (United States)

    2015-08-01

    backpressure can decrease engine power by ~1% per inch Hg.27 A specific exhaust heat exchanger design would need to take this effect into account...Materials. 2009;39:2142–2148. 4. Sprouse III C, Depcik C. Review of organic Rankine cycles for internal combustion engine exhaust waste heat recovery...Adams TG. Effect of exhaust system design on engine performance. 1980. SAE Technical Paper No. 800319. 16 1 DEFENSE TECHNICAL

  10. Managers as role models for health: Moderators of the relationship of transformational leadership with employee exhaustion and cynicism.

    Science.gov (United States)

    Kranabetter, Caroline; Niessen, Cornelia

    2017-10-01

    Drawing on social learning literature, this study examined managers' health awareness and health behavior (health-related self-regulation) as a moderator of the relationships between transformational leadership and employee exhaustion and cynicism. In 2 organizations, employees (n = 247; n = 206) rated their own exhaustion and cynicism, and their managers' transformational leadership. Managers (n = 57; n = 30) assessed their own health-related self-regulation. Multilevel modeling showed that, as expected, managers' health awareness moderated the relationship between transformational leadership and employee exhaustion and cynicism. Employees experienced less exhaustion and cynicism when transformational leaders were aware of their own health. Managers' health behavior moderated the relationship between transformational leadership and employee exhaustion in 1 organization, but not in the other. With respect to health behavior, we found no significant results for employee cynicism. In sum, the results indicate that when managers are role models for health, employees will benefit more from the transformational leadership style. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  11. Theoretical and Experimental Aspects of Acoustic Modelling of Engine Exhaust Systems with Applications to a Vacuum Pump

    Science.gov (United States)

    Sridhara, Basavapatna Sitaramaiah

    In an internal combustion engine, the engine is the noise source and the exhaust pipe is the main transmitter of noise. Mufflers are often used to reduce engine noise level in the exhaust pipe. To optimize a muffler design, a series of experiments could be conducted using various mufflers installed in the exhaust pipe. For each configuration, the radiated sound pressure could be measured. However, this is not a very efficient method. A second approach would be to develop a scheme involving only a few measurements which can predict the radiated sound pressure at a specified distance from the open end of the exhaust pipe. In this work, the engine exhaust system was modelled as a lumped source-muffler-termination system. An expression for the predicted sound pressure level was derived in terms of the source and termination impedances, and the muffler geometry. The pressure source and monopole radiation models were used for the source and the open end of the exhaust pipe. The four pole parameters were used to relate the acoustic properties at two different cross sections of the muffler and the pipe. The developed formulation was verified through a series of experiments. Two loudspeakers and a reciprocating type vacuum pump were used as sound sources during the tests. The source impedance was measured using the direct, two-load and four-load methods. A simple expansion chamber and a side-branch resonator were used as mufflers. Sound pressure level measurements for the prediction scheme were made for several source-muffler and source-straight pipe combinations. The predicted and measured sound pressure levels were compared for all cases considered. In all cases, correlation of the experimental results and those predicted by the developed expressions was good. Predicted and measured values of the insertion loss of the mufflers were compared. The agreement between the two was good. Also, an error analysis of the four-load method was done.

  12. A Model for the Infrared Radiance of Optically Thin, Particulate Exhaust Plumes Generated by Pyrotechnic Flares Burning in a Vacuum

    National Research Council Canada - National Science Library

    Cohen, Douglas

    2000-01-01

    .... The model is used to predict how a magnesium-Teflon exhaust plume would look when viewed as an approximate point source by a distant infrared sensor and also to analyze the data acquired from three separate magnesium-Teflon flares burned in a large vacuum chamber.

  13. TNKVNT: A model of the Tank 48 purge/ventilation exhaust system. Revision 1

    International Nuclear Information System (INIS)

    Shadday, M.A. Jr.

    1996-04-01

    The waste tank purge ventilation system for Tank 48 is designed to prevent dangerous concentrations of hydrogen or benzene from accumulating in the gas space of the tank. Fans pull the gas/water vapor mixture from the tank gas space and pass it sequentially through a demister, a condenser, a reheater, and HEPA filters before discharging to the environment. Proper operation of the HEPA filters requires that the gas mixture passing through them has a low relative humidity. The ventilation system has been modified by increasing the capacity of the fans and changing the condenser from a two-pass heat exchanger to a single-pass heat exchanger. It is important to understand the impact of these modifications on the operation of the system. A hydraulic model of the ventilation exhaust system has been developed. This model predicts the properties of the air throughout the system and the flowrate through the system, as functions of the tank gas space and environmental conditions. This document serves as a Software Design Report, a Software Coding report, and a User's Manual. All of the information required for understanding and using this code is herein contained: the governing equations are fully developed, the numerical algorithms are described in detail, and an extensively commented code listing is included. This updated version of the code models the entire purge ventilation system, and is therefore more general in its potential applications

  14. Extension of an assessment model of ship traffic exhaust emissions for particulate matter and carbon monoxide

    Directory of Open Access Journals (Sweden)

    J.-P. Jalkanen

    2012-03-01

    Full Text Available A method is presented for the evaluation of the exhaust emissions of marine traffic, based on the messages provided by the Automatic Identification System (AIS, which enable the positioning of ship emissions with a high spatial resolution (typically a few tens of metres. The model also takes into account the detailed technical data of each individual vessel. The previously developed model was applicable for evaluating the emissions of NOx, SOx and CO2. This paper addresses a substantial extension of the modelling system, to allow also for the mass-based emissions of particulate matter (PM and carbon monoxide (CO. The presented Ship Traffic Emissions Assessment Model (STEAM2 allows for the influences of accurate travel routes and ship speed, engine load, fuel sulphur content, multiengine setups, abatement methods and waves. We address in particular the modeling of the influence on the emissions of both engine load and the sulphur content of the fuel. The presented methodology can be used to evaluate the total PM emissions, and those of organic carbon, elemental carbon, ash and hydrated sulphate. We have evaluated the performance of the extended model against available experimental data on engine power, fuel consumption and the composition-resolved emissions of PM. We have also compared the annually averaged emission values with those of the corresponding EMEP inventory, As example results, the geographical distributions of the emissions of PM and CO are presented for the marine regions of the Baltic Sea surrounding the Danish Straits.

  15. Experimental aerodynamic and acoustic model testing of the Variable Cycle Engine (VCE) testbed coannular exhaust nozzle system: Comprehensive data report

    Science.gov (United States)

    Nelson, D. P.; Morris, P. M.

    1980-01-01

    The component detail design drawings of the one sixth scale model of the variable cycle engine testbed demonstrator exhaust syatem tested are presented. Also provided are the basic acoustic and aerodynamic data acquired during the experimental model tests. The model drawings, an index to the acoustic data, an index to the aerodynamic data, tabulated and graphical acoustic data, and the tabulated aerodynamic data and graphs are discussed.

  16. Modelling exhaust plume mixing in the near field of an aircraft

    Directory of Open Access Journals (Sweden)

    F. Garnier

    Full Text Available A simplified approach has been applied to analyse the mixing and entrainment processes of the engine exhaust through their interaction with the vortex wake of an aircraft. Our investigation is focused on the near field, extending from the exit nozzle until about 30 s after the wake is generated, in the vortex phase. This study was performed by using an integral model and a numerical simulation for two large civil aircraft: a two-engine Airbus 330 and a four-engine Boeing 747. The influence of the wing-tip vortices on the dilution ratio (defined as a tracer concentration shown. The mixing process is also affected by the buoyancy effect, but only after the jet regime, when the trapping in the vortex core has occurred. In the early wake, the engine jet location (i.e. inboard or outboard engine jet has an important influence on the mixing rate. The plume streamlines inside the vortices are subject to distortion and stretching, and the role of the descent of the vortices on the maximum tracer concentration is discussed. Qualitative comparison with contrail photograph shows similar features. Finally, tracer concentration of inboard engine centreline of B-747 are compared with other theoretical analyses and measured data.

  17. Tokamak fusion reactor exhaust

    International Nuclear Information System (INIS)

    Harrison, M.F.A.; Harbour, P.J.; Hotston, E.S.

    1981-08-01

    This report presents a compilation of papers dealing with reactor exhaust which were produced as part of the TIGER Tokamak Installation for Generating Electricity study at Culham. The papers are entitled: (1) Exhaust impurity control and refuelling. (2) Consideration of the physical problems of a self-consistent exhaust and divertor system for a long burn Tokamak. (3) Possible bundle divertors for INTOR and TIGER. (4) Consideration of various magnetic divertor configurations for INTOR and TIGER. (5) A appraisal of divertor experiments. (6) Hybrid divertors on INTOR. (7) Refuelling and the scrape-off layer of INTOR. (8) Simple modelling of the scrape-off layer. (9) Power flow in the scrape-off layer. (10) A model of particle transport within the scrape-off plasma and divertor. (11) Controlled recirculation of exhaust gas from the divertor into the scrape-off plasma. (U.K.)

  18. Dilution of aircraft exhaust and entrainment rates for trajectory box models

    Energy Technology Data Exchange (ETDEWEB)

    Gerz, T [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Kaercher, B [Muenchen Univ. (Germany). Lehrstuhl fuer Bioklimatologie und Immissionsforschung

    1998-12-31

    In order to match in-situ measured concentrations of NO and NO{sub 2} in the wake, dilution factors or entrainment rates have to be used which take into account that the largest fraction of the exhaust is captured by the wing tip vortices. This fraction defines the primary wake. Baroclinicity and turbulence detrains parts of it later into the secondary wake. Both wake regimes undergo different chemical and microphysical histories. The rates {omega} are determined at which ambient air becomes entrained into the primary and the secondary portion of the exhaust plume. Numerical simulations of the highly resolved wake is used of cruising aircraft under typical atmosphere conditions with and without ambient turbulence. The simulations are oriented on a case where exhaust and dynamical data behind an eastbound travelling B-747 aircraft have been collected in-situ over the North-Atlantic east of Ireland. (author) 7 refs.

  19. Dilution of aircraft exhaust and entrainment rates for trajectory box models

    Energy Technology Data Exchange (ETDEWEB)

    Gerz, T. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Kaercher, B. [Muenchen Univ. (Germany). Lehrstuhl fuer Bioklimatologie und Immissionsforschung

    1997-12-31

    In order to match in-situ measured concentrations of NO and NO{sub 2} in the wake, dilution factors or entrainment rates have to be used which take into account that the largest fraction of the exhaust is captured by the wing tip vortices. This fraction defines the primary wake. Baroclinicity and turbulence detrains parts of it later into the secondary wake. Both wake regimes undergo different chemical and microphysical histories. The rates {omega} are determined at which ambient air becomes entrained into the primary and the secondary portion of the exhaust plume. Numerical simulations of the highly resolved wake is used of cruising aircraft under typical atmosphere conditions with and without ambient turbulence. The simulations are oriented on a case where exhaust and dynamical data behind an eastbound travelling B-747 aircraft have been collected in-situ over the North-Atlantic east of Ireland. (author) 7 refs.

  20. Observations and model calculations of B747 engine exhaust products at cruise altitude and inferred initial OH emissions

    Energy Technology Data Exchange (ETDEWEB)

    Tremmel, H.G.; Schlager, H.; Konopka, P.; Schulte, P. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Wessling (Germany). Inst. fuer Physik der Atmosphaere; Arnold, F.; Klemm, M.; Droste-Franke, B. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    1997-06-01

    NO{sub y} (NO, HNO{sub 2} and HNO{sub 3}) exhaust emissions in the near-field plume of two B747 jet airliners cruising in the upper troposphere were measured in situ using the DLR Falcon research aircraft. In addition CO{sub 2} was measured providing exhaust plume dilution rates for the species. The observations were used to estimate the initial OH concentration and NO{sub 2}/NO{sub x} ratio at the engine exit and the combustor exit by back calculations using a chemistry box model. From the two different plume events, and using two different model simulation modes in each case, we inferred OH emission indices EI(OH) = 0.32-0.39 g/kg fuel (OH{sub 0} = 9-14.4 ppmv) and (NO{sub 2}/NO{sub x}){sub 0} = 0.12-0.17. Furthermore, our results indicate that the chemistry of the exhaust species during the short period between the combustion chamber exit and the engine exit must be considered, because OH is already consumed to a great extent in this engine section, due to conversion to HNO{sub 2} and HNO{sub 3}. For the engines discussed here, the modeled OH concentration between combustor exit und engine exit decreases by a factor of about 350, leading to OH concentrations of 1-2.10{sup 12} molec/cm{sup 3} at the engine exit. (orig.) 45 refs.

  1. Estimation of exhaust gas aerodynamic force on the variable geometry turbocharger actuator: 1D flow model approach

    International Nuclear Information System (INIS)

    Ahmed, Fayez Shakil; Laghrouche, Salah; Mehmood, Adeel; El Bagdouri, Mohammed

    2014-01-01

    Highlights: • Estimation of aerodynamic force on variable turbine geometry vanes and actuator. • Method based on exhaust gas flow modeling. • Simulation tool for integration of aerodynamic force in automotive simulation software. - Abstract: This paper provides a reliable tool for simulating the effects of exhaust gas flow through the variable turbine geometry section of a variable geometry turbocharger (VGT), on flow control mechanism. The main objective is to estimate the resistive aerodynamic force exerted by the flow upon the variable geometry vanes and the controlling actuator, in order to improve the control of vane angles. To achieve this, a 1D model of the exhaust flow is developed using Navier–Stokes equations. As the flow characteristics depend upon the volute geometry, impeller blade force and the existing viscous friction, the related source terms (losses) are also included in the model. In order to guarantee stability, an implicit numerical solver has been developed for the resolution of the Navier–Stokes problem. The resulting simulation tool has been validated through comparison with experimentally obtained values of turbine inlet pressure and the aerodynamic force as measured at the actuator shaft. The simulator shows good compliance with experimental results

  2. Mixed gated/exhaustive service in a polling model with priorities

    NARCIS (Netherlands)

    Boon, M.A.A.; Adan, I.J.B.F.

    2008-01-01

    In this paper we consider a single-server polling system with switch-over times. We introduce a new service discipline, mixed gated/exhaustive service, that can be used for queues with two types of customers: high and low priority customers. At the beginning of a visit of the server to such a queue,

  3. Modeling Macro- and Micro-Scale Turbulent Mixing and Chemistry in Engine Exhaust Plumes

    Science.gov (United States)

    Menon, Suresh

    1998-01-01

    Simulation of turbulent mixing and chemical processes in the near-field plume and plume-vortex regimes has been successfully carried out recently using a reduced gas phase kinetics mechanism which substantially decreased the computational cost. A detailed mechanism including gas phase HOx, NOx, and SOx chemistry between the aircraft exhaust and the ambient air in near-field aircraft plumes is compiled. A reduced mechanism capturing the major chemical pathways is developed. Predictions by the reduced mechanism are found to be in good agreement with those by the detailed mechanism. With the reduced chemistry, the computer CPU time is saved by a factor of more than 3.5 for the near-field plume modeling. Distributions of major chemical species are obtained and analyzed. The computed sensitivities of major species with respect to reaction step are deduced for identification of the dominant gas phase kinetic reaction pathways in the jet plume. Both the near field plume and the plume-vortex regimes were investigated using advanced mixing models. In the near field, a stand-alone mixing model was used to investigate the impact of turbulent mixing on the micro- and macro-scale mixing processes using a reduced reaction kinetics model. The plume-vortex regime was simulated using a large-eddy simulation model. Vortex plume behind Boeing 737 and 747 aircraft was simulated along with relevant kinetics. Many features of the computed flow field show reasonable agreement with data. The entrainment of the engine plumes into the wing tip vortices and also the partial detrainment of the plume were numerically captured. The impact of fluid mechanics on the chemical processes was also studied. Results show that there are significant differences between spatial and temporal simulations especially in the predicted SO3 concentrations. This has important implications for the prediction of sulfuric acid aerosols in the wake and may partly explain the discrepancy between past numerical studies

  4. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model

    Energy Technology Data Exchange (ETDEWEB)

    Pecorari, Eliana, E-mail: eliana.pecorari@unive.it [Department of Environmental Science, Informatics and Statistics, University Ca’ Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia (Italy); Mantovani, Alice [OSMOTECH S.r.l., via Francesco Sforza, 15, 20122 Milano (Italy); Franceschini, Chiara [Department of Environmental Science, Informatics and Statistics, University Ca’ Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia (Italy); Bassano, Davide [SAVE S.p.A., Marco Polo Venice airport viale G. Galilei 30/1, 30173 Tessera-Venezia (Italy); Palmeri, Luca [Department of Industrial Engineering, University of Padova, v. Marzolo 9, 35131 Padova (Italy); Rampazzo, Giancarlo [Department of Environmental Science, Informatics and Statistics, University Ca’ Foscari Venice, Calle Larga Santa Marta 2137, Dorsoduro, 30123 Venezia (Italy)

    2016-01-15

    The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po’ Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15–50%) has been observed during specific meteorological events

  5. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model

    International Nuclear Information System (INIS)

    Pecorari, Eliana; Mantovani, Alice; Franceschini, Chiara; Bassano, Davide; Palmeri, Luca; Rampazzo, Giancarlo

    2016-01-01

    The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po’ Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15–50%) has been observed during specific meteorological events

  6. Numerically Modeling the Erosion of Lunar Soil by Rocket Exhaust Plumes

    Science.gov (United States)

    2008-01-01

    In preparation for the Apollo program, Leonard Roberts of the NASA Langley Research Center developed a remarkable analytical theory that predicts the blowing of lunar soil and dust beneath a rocket exhaust plume. Roberts assumed that the erosion rate was determined by the excess shear stress in the gas (the amount of shear stress greater than what causes grains to roll). The acceleration of particles to their final velocity in the gas consumes a portion of the shear stress. The erosion rate continues to increase until the excess shear stress is exactly consumed, thus determining the erosion rate. Roberts calculated the largest and smallest particles that could be eroded based on forces at the particle scale, but the erosion rate equation assumed that only one particle size existed in the soil. He assumed that particle ejection angles were determined entirely by the shape of the terrain, which acts like a ballistic ramp, with the particle aerodynamics being negligible. The predicted erosion rate and the upper limit of particle size appeared to be within an order of magnitude of small-scale terrestrial experiments but could not be tested more quantitatively at the time. The lower limit of particle size and the predictions of ejection angle were not tested. We observed in the Apollo landing videos that the ejection angles of particles streaming out from individual craters were time-varying and correlated to the Lunar Module thrust, thus implying that particle aerodynamics dominate. We modified Roberts theory in two ways. First, we used ad hoc the ejection angles measured in the Apollo landing videos, in lieu of developing a more sophisticated method. Second, we integrated Roberts equations over the lunar-particle size distribution and obtained a compact expression that could be implemented in a numerical code. We also added a material damage model that predicts the number and size of divots which the impinging particles will cause in hardware surrounding the landing

  7. Hazard identification of exhausts from gasoline-ethanol fuel blends using a multi-cellular human lung model.

    Science.gov (United States)

    Bisig, Christoph; Roth, Michèle; Müller, Loretta; Comte, Pierre; Heeb, Norbert; Mayer, Andreas; Czerwinski, Jan; Petri-Fink, Alke; Rothen-Rutishauser, Barbara

    2016-11-01

    Ethanol can be produced from biomass and as such is renewable, unlike petroleum-based fuel. Almost all gasoline cars can drive with fuel containing 10% ethanol (E10), flex-fuel cars can even use 85% ethanol (E85). Brazil and the USA already include 10-27% ethanol in their standard fuel by law. Most health effect studies on car emissions are however performed with diesel exhausts, and only few data exists for other fuels. In this work we investigated possible toxic effects of exhaust aerosols from ethanol-gasoline blends using a multi-cellular model of the human lung. A flex-fuel passenger car was driven on a chassis dynamometer and fueled with E10, E85, or pure gasoline (E0). Exhausts obtained from a steady state cycle were directly applied for 6h at a dilution of 1:10 onto a multi-cellular human lung model mimicking the bronchial compartment composed of human bronchial cells (16HBE14o-), supplemented with human monocyte-derived dendritic cells and monocyte-derived macrophages, cultured at the air-liquid interface. Biological endpoints were assessed after 6h post incubation and included cytotoxicity, pro-inflammation, oxidative stress, and DNA damage. Filtered air was applied to control cells in parallel to the different exhausts; for comparison an exposure to diesel exhaust was also included in the study. No differences were measured for the volatile compounds, i.e. CO, NO x , and T.HC for the different ethanol supplemented exhausts. Average particle number were 6×10 2 #/cm 3 (E0), 1×10 5 #/cm 3 (E10), 3×10 3 #/cm 3 (E85), and 2.8×10 6 #/cm 3 (diesel). In ethanol-gasoline exposure conditions no cytotoxicity and no morphological changes were observed in the lung cell cultures, in addition no oxidative stress - as analyzed with the glutathione assay - was measured. Gene expression analysis also shows no induction in any of the tested genes, including mRNA levels of genes related to oxidative stress and pro-inflammation, as well as indoleamine 2,3-dioxygenase 1

  8. Results of subscale MTF compression experiments

    Science.gov (United States)

    Howard, Stephen; Mossman, A.; Donaldson, M.; Fusion Team, General

    2016-10-01

    In magnetized target fusion (MTF) a magnetized plasma torus is compressed in a time shorter than its own energy confinement time, thereby heating to fusion conditions. Understanding plasma behavior and scaling laws is needed to advance toward a reactor-scale demonstration. General Fusion is conducting a sequence of subscale experiments of compact toroid (CT) plasmas being compressed by chemically driven implosion of an aluminum liner, providing data on several key questions. CT plasmas are formed by a coaxial Marshall gun, with magnetic fields supported by internal plasma currents and eddy currents in the wall. Configurations that have been compressed so far include decaying and sustained spheromaks and an ST that is formed into a pre-existing toroidal field. Diagnostics measure B, ne, visible and x-ray emission, Ti and Te. Before compression the CT has an energy of 10kJ magnetic, 1 kJ thermal, with Te of 100 - 200 eV, ne 5x1020 m-3. Plasma was stable during a compression factor R0/R >3 on best shots. A reactor scale demonstration would require 10x higher initial B and ne but similar Te. Liner improvements have minimized ripple, tearing and ejection of micro-debris. Plasma facing surfaces have included plasma-sprayed tungsten, bare Cu and Al, and gettering with Ti and Li.

  9. Analysis of the effects of meteorology on aircraft exhaust dispersion and deposition using a Lagrangian particle model.

    Science.gov (United States)

    Pecorari, Eliana; Mantovani, Alice; Franceschini, Chiara; Bassano, Davide; Palmeri, Luca; Rampazzo, Giancarlo

    2016-01-15

    The risk of air quality degradation is of considerable concern particularly for those airports that are located near urban areas. The ability to quantitatively predict the effects of air pollutants originated by airport operations is important for assessing air quality and the related impacts on human health. Current emission regulations have focused on local air quality in the proximity of airports. However, an integrated study should consider the effects of meteorological events, at both regional and local level, that can affect the dispersion and the deposition of exhausts. Rigorous scientific studies and extensive experimental data could contribute to the analysis of the impacts of airports expansion plans. This paper is focused on the analysis of the effects of meteorology on aircraft emission for the Marco Polo Airport in Venice. This is the most important international airport in the eastern part of the Po' Valley, one of the most polluted area in Europe. Air pollution is exacerbated by meteorology that is a combination of large and local scale effects that do not allow significant dispersion. Moreover, the airport is located near Venice, a city of noteworthy cultural and architectural relevance, and nearby the lagoon that hosts several areas of outstanding ecological importance at European level (Natura 2000 sites). Dispersion and deposit of the main aircraft exhausts (NOx, HC and CO) have been evaluated by using a Lagrangian particle model. Spatial and temporal aircraft exhaust dispersion has been analyzed for LTO cycle. Aircraft taxiing resulted to be the most impacting aircraft operation especially for the airport working area and its surroundings, however occasionally peaks may be observed even at high altitudes when cruise mode starts. Mixing height can affect concentrations more significantly than the concentrations in the exhausts themselves. An increase of HC and CO concentrations (15-50%) has been observed during specific meteorological events

  10. Simplified fuel cycle tritium inventory model for systems studies -- An illustrative example with an optimized cryopump exhaust system

    International Nuclear Information System (INIS)

    Kuan, W.; Ho, S.K.

    1995-01-01

    It is desirable to incorporate safety constraints due to fuel cycle tritium inventories into tokamak reactor design optimization. An optimal scenario to minimize tritium inventories without much degradation of plasma performance can be defined for each tritium processing component. In this work, the computer code TRUFFLES is used exclusively to obtain numerical data for a simplified model to be used for systems studies. As an illustration, the cryopump plasma exhaust subsystem is examined in detail for optimization purposes. This optimization procedure will then be used to further reduce its window of operation and provide constraints on the data used for the simplified tritium inventory model

  11. Emotional Exhaustion and Job Satisfaction in Airport Security Officers - Work-Family Conflict as Mediator in the Job Demands-Resources Model.

    Science.gov (United States)

    Baeriswyl, Sophie; Krause, Andreas; Schwaninger, Adrian

    2016-01-01

    The growing threat of terrorism has increased the importance of aviation security and the work of airport security officers (screeners). Nonetheless, airport security research has yet to focus on emotional exhaustion and job satisfaction as major determinants of screeners' job performance. The present study bridges this research gap by applying the job demands-resources (JD-R) model and using work-family conflict (WFC) as an intervening variable to study relationships between work characteristics (workload and supervisor support), emotional exhaustion, and job satisfaction in 1,127 screeners at a European airport. Results of structural equation modeling revealed that (a) supervisor support as a major job resource predicted job satisfaction among screeners; (b) workload as a major job demand predicted their emotional exhaustion; and (c) WFC proved to be a promising extension to the JD-R model that partially mediated the impact of supervisor support and workload on job satisfaction and emotional exhaustion. Theoretical and practical implications are discussed.

  12. Experimental aerodynamic and acoustic model testing of the Variable Cycle Engine (VCE) testbed coannular exhaust nozzle system

    Science.gov (United States)

    Nelson, D. P.; Morris, P. M.

    1980-01-01

    Aerodynamic performance and jet noise characteristics of a one sixth scale model of the variable cycle engine testbed exhaust system were obtained in a series of static tests over a range of simulated engine operating conditions. Model acoustic data were acquired. Data were compared to predictions of coannular model nozzle performance. The model, tested with an without a hardwall ejector, had a total flow area equivalent to a 0.127 meter (5 inch) diameter conical nozzle with a 0.65 fan to primary nozzle area ratio and a 0.82 fan nozzle radius ratio. Fan stream temperatures and velocities were varied from 422 K to 1089 K (760 R to 1960 R) and 434 to 755 meters per second (1423 to 2477 feet per second). Primary stream properties were varied from 589 to 1089 K (1060 R to 1960 R) and 353 to 600 meters per second (1158 to 1968 feet per second). Exhaust plume velocity surveys were conducted at one operating condition with and without the ejector installed. Thirty aerodynamic performance data points were obtained with an unheated air supply. Fan nozzle pressure ratio was varied from 1.8 to 3.2 at a constant primary pressure ratio of 1.6; primary pressure ratio was varied from 1.4 to 2.4 while holding fan pressure ratio constant at 2.4. Operation with the ejector increased nozzle thrust coefficient 0.2 to 0.4 percent.

  13. Comparison of Airway Responses Induced in a Mouse Model by the Gas and Particulate Fractions of Gasoline Direct Injection Engine Exhaust.

    Science.gov (United States)

    Maikawa, Caitlin L; Zimmerman, Naomi; Ramos, Manuel; Shah, Mittal; Wallace, James S; Pollitt, Krystal J Godri

    2018-03-01

    Diesel exhaust has been associated with asthma, but its response to other engine emissions is not clear. The increasing prevalence of vehicles with gasoline direct injection (GDI) engines motivated this study, and the objective was to evaluate pulmonary responses induced by acute exposure to GDI engine exhaust in an allergic asthma murine model. Mice were sensitized with an allergen to induce airway hyperresponsiveness or treated with saline (non-allergic group). Animals were challenged for 2-h to exhaust from a laboratory GDI engine operated at conditions equivalent to a highway cruise. Exhaust was filtered to assess responses induced by the particulate and gas fractions. Short-term exposure to particulate matter from GDI engine exhaust induced upregulation of genes related to polycyclic aromatic hydrocarbon (PAH) metabolism ( Cyp1b1 ) and inflammation ( TNFα ) in the lungs of non-allergic mice. High molecular weight PAHs dominated the particulate fraction of the exhaust, and this response was therefore likely attributable to the presence of these PAHs. The particle fraction of GDI engine exhaust further contributed to enhanced methacholine responsiveness in the central and peripheral tissues in animals with airway hyperresponsiveness. As GDI engines gain prevalence in the vehicle fleet, understanding the health impacts of their emissions becomes increasingly important.

  14. Comparison of Airway Responses Induced in a Mouse Model by the Gas and Particulate Fractions of Gasoline Direct Injection Engine Exhaust

    Directory of Open Access Journals (Sweden)

    Caitlin L. Maikawa

    2018-03-01

    Full Text Available Diesel exhaust has been associated with asthma, but its response to other engine emissions is not clear. The increasing prevalence of vehicles with gasoline direct injection (GDI engines motivated this study, and the objective was to evaluate pulmonary responses induced by acute exposure to GDI engine exhaust in an allergic asthma murine model. Mice were sensitized with an allergen to induce airway hyperresponsiveness or treated with saline (non-allergic group. Animals were challenged for 2-h to exhaust from a laboratory GDI engine operated at conditions equivalent to a highway cruise. Exhaust was filtered to assess responses induced by the particulate and gas fractions. Short-term exposure to particulate matter from GDI engine exhaust induced upregulation of genes related to polycyclic aromatic hydrocarbon (PAH metabolism (Cyp1b1 and inflammation (TNFα in the lungs of non-allergic mice. High molecular weight PAHs dominated the particulate fraction of the exhaust, and this response was therefore likely attributable to the presence of these PAHs. The particle fraction of GDI engine exhaust further contributed to enhanced methacholine responsiveness in the central and peripheral tissues in animals with airway hyperresponsiveness. As GDI engines gain prevalence in the vehicle fleet, understanding the health impacts of their emissions becomes increasingly important.

  15. Exhaust gas processing facility

    International Nuclear Information System (INIS)

    Terada, Shin-ichi.

    1995-01-01

    The facility of the present invention comprises a radioactive liquid storage vessel, an exhaust gas dehumidifying device for dehumidifying gases exhausted from the vessel and an exhaust gas processing device for reducing radioactive materials in the exhaust gases. A purified gas line is disposed to the radioactive liquid storage vessel for purging exhaust gases generated from the radioactive liquid, then dehumidified and condensed liquid is recovered, and exhaust gases are discharged through an exhaust gas pipe disposed downstream of the exhaust gas processing device. With such procedures, the scale of the exhaust gas processing facility can be reduced and exhaust gases can be processed efficiently. (T.M.)

  16. Modeling the integration of thermoelectrics in anode exhaust combustors for waste heat recovery in fuel cell systems

    Science.gov (United States)

    Maghdouri Moghaddam, Anita

    Recently developed small-scale hydrocarbon-fueled fuel cell systems for portable power under 1 kW have overall system efficiencies typically no higher than 30-35%. This study explores the possibility of using of thermoelectric waste heat recovery in anode exhaust combustors to improve the fuel cell system efficiencies by as much as 4-5% points and further to reduce required battery power during system start-up. Two models were used to explore this. The first model simulated an integrated SOFC system with a simplified catalytic combustor model with TEs integrated between the combustor and air preheating channels for waste heat recovery. This model provided the basis for assessing how much additional power can achieve during SOFC operation as a function of fuel cell operating conditions. Results for the SOFC system indicate that while the TEs may recover as much as 4% of the total fuel energy into the system, their benefit is reduced in part because they reduce the waste heat transferred back to the incoming air stream and thereby lower the SOFC operating temperatures and operating efficiencies. A second model transient model of a TE-integrated catalytic combustor explored the performance of the TEs during transient start-up of the combustor. This model incorporated more detailed catalytic combustion chemistry and enhanced cooling air fin heat transfer to show the dynamic heating of the integrated combustor. This detailed model provided a basis for exploring combustor designs and showed the importance of adequate reactant preheating when burning exhaust from a reformer during start-up for the TEs to produce significant power to reduce the size of system batteries for start-up.

  17. Turnover intention and emotional exhaustion "at the top": adapting the job demands-resources model to leaders of addiction treatment organizations.

    Science.gov (United States)

    Knudsen, Hannah K; Ducharme, Lori J; Roman, Paul M

    2009-01-01

    Compared with the large literature on subordinate employees, there are few studies of emotional exhaustion and turnover intention for organizational leaders. There is little research that has extended the job demands-resources (JD-R) model of emotional exhaustion to leaders. In this study, the authors adapted the JD-R framework to analyze data collected from a sample of 410 leaders of addiction treatment organizations. The authors considered whether two job demands (performance demands and centralization) and two job resources (innovation in decision making and long-range strategic planning) were associated with emotional exhaustion and turnover intention. The authors also examined whether emotional exhaustion fully or partially mediated the associations between the job-related measures and turnover intention. The results supported the partially mediated model. Both job demands were positively associated with emotional exhaustion, and the association for long-range strategic planning was negative. Emotional exhaustion was positively associated with turnover intention. Centralization and innovation in decision making were also directly associated with turnover intention. Future research should continue to examine this theoretical framework among leaders of other types of organizations using more refined measures of demands and resources.

  18. Turnover intention and emotional exhaustion “at the top”: Adapting the job demands-resources model to leaders of addiction treatment organizations

    Science.gov (United States)

    Knudsen, Hannah K.; Ducharme, Lori J.; Roman, Paul M.

    2009-01-01

    Compared to the large literature on subordinate employees, there are few studies of emotional exhaustion and turnover intention for organizational leaders. There is little research that has extended the job demands-resources (JD-R) model of emotional exhaustion to leaders. In this study, we adapted the JD-R framework in order to analyze data collected from a sample of 410 leaders of addiction treatment organizations. We considered whether two job demands (performance demands and centralization) and two job resources (innovation in decision-making and long-range strategic planning) were associated with emotional exhaustion and turnover intention. We also examined whether emotional exhaustion fully or partially mediated the associations between the job-related measures and turnover intention. The results supported the partially mediated model. Both job demands were positively associated with emotional exhaustion, while the association for long-range strategic planning was negative. Emotional exhaustion was positively associated with turnover intention. Centralization and innovation in decision-making were also directly associated with turnover intention. Future research should continue to examine this theoretical framework among leaders of other types of organizations using more refined measures of demands and resources. PMID:19210050

  19. Software Considerations for Subscale Flight Testing of Experimental Control Laws

    Science.gov (United States)

    Murch, Austin M.; Cox, David E.; Cunningham, Kevin

    2009-01-01

    The NASA AirSTAR system has been designed to address the challenges associated with safe and efficient subscale flight testing of research control laws in adverse flight conditions. In this paper, software elements of this system are described, with an emphasis on components which allow for rapid prototyping and deployment of aircraft control laws. Through model-based design and automatic coding a common code-base is used for desktop analysis, piloted simulation and real-time flight control. The flight control system provides the ability to rapidly integrate and test multiple research control laws and to emulate component or sensor failures. Integrated integrity monitoring systems provide aircraft structural load protection, isolate the system from control algorithm failures, and monitor the health of telemetry streams. Finally, issues associated with software configuration management and code modularity are briefly discussed.

  20. Hot-gas-side heat transfer characteristics of subscale, plug-nozzle rocket calorimeter chamber

    Science.gov (United States)

    Quentmeyer, Richard J.; Roncace, Elizabeth A.

    1993-01-01

    An experimental investigation was conducted to determine the hot-gas-side heat transfer characteristics for a liquid-hydrogen-cooled, subscale, plug-nozzle rocket test apparatus. This apparatus has been used since 1975 to evaluate rocket engine advanced cooling concepts and fabrication techniques, to screen candidate combustion chamber liner materials, and to provide data for model development. In order to obtain the data, a water-cooled calorimeter chamber having the same geometric configuration as the plug-nozzle test apparatus was tested. It also used the same two showerhead injector types that were used on the test apparatus: one having a Rigimesh faceplate and the other having a platelet faceplate. The tests were conducted using liquid oxygen and gaseous hydrogen as the propellants over a mixture ratio range of 5.8 to 6.3 at a nominal chamber pressure of 4.14 MPa abs (600 psia). The two injectors showed similar performance characteristics with the Rigimesh faceplate having a slightly higher average characteristic-exhaust-velocity efficiency of 96 percent versus 94.4 percent for the platelet faceplate. The throat heat flux was 54 MW/m(sup 2) (33 Btu/in.(sup 2)-sec) at the nominal operating condition, which was a chamber pressure of 4.14 MPa abs (600 psia), a hot-gas-side wall temperature of 730 K (1314 R), and a mixture ratio of 6.0. The chamber throat region correlation coefficient C(sub g) for a Nusselt number correlation of the form Nu =C(sub g)Re(sup 0.8)Pr(sup 0.3) averaged 0.023 for the Rigimesh faceplate and 0.026 for the platelet faceplate.

  1. Dish/Stirling Hybrid-Receiver Sub-Scale Tests and Full-Scale Design

    International Nuclear Information System (INIS)

    Andraka, Charles; Bohn, Mark S.; Corey, John; Mehos, Mark; Moreno, James; Rawlinson, Scott

    1999-01-01

    We have designed and tested a prototype dish/Stirling hybrid-receiver combustion system. The system consists of a pre-mixed natural-gas burner heating a pin-finned sodium heat pipe. The design emphasizes simplicity, low cost, and ruggedness. Our test was on a 1/6 th -scale device, with a nominal firing rate of 18kWt, a power throughput of 13kWt, and a sodium vapor temperature of 750 ampersand deg;C. The air/fuel mixture was electrically preheated to 640 ampersand deg;C to simulate recuperation. The test rig was instrumented for temperatures, pressures, flow rates, overall leak rate, and exhaust emissions. The data verify our burner and heat-transfer models. Performance and post-test examinations validate our choice of materials and fabrication methods. Based on the 1/6 th -scale results, we are designing a till-scale hybrid receiver. This is a fully-integrated system, including burner, pin-fin primary heat exchanger, recuperator (in place of the electrical pre-heater used in the prototype system), solar absorber, and sodium heat pipe. The major challenges of the design are to avoid pre-ignition, achieve robust heat-pipe performance, and attain long life of the burner matrix, recuperator, and flue-gas seals. We have used computational fluid dynamics extensively in designing to avoid pre-ignition and for designing the heat-pipe wick, and we have used individual component tests and results of the 1/6 th -scale test to optimize for long life. In this paper, we present our design philosophy and basic details of our design. We describe the sub-scale test rig and compare test results with predictions. Finally, we outline the evolution of our full-scale design, and present its current status

  2. Control-oriented modeling of two-stroke diesel engines with exhaust gas recirculation for marine applications

    OpenAIRE

    Llamas, Xavier; Eriksson, Lars

    2018-01-01

    Large marine two-stroke diesel engines are widely used as propulsion systems for shipping worldwide and are facing stricter NOx emission limits. Exhaust gas recirculation is introduced to these engines to reduce the produced combustion NOx to the allowed levels. Since the current number of engines built with exhaust gas recirculation is low and engine testing is very expensive, a powerful alternative for developing exhaust gas recirculation controllers for such engines is to use control-orien...

  3. Item-level and subscale-level factoring of Biggs' Learning Process Questionnaire (LPQ) in a mainland Chinese sample.

    Science.gov (United States)

    Sachs, J; Gao, L

    2000-09-01

    The learning process questionnaire (LPQ) has been the source of intensive cross-cultural study. However, an item-level factor analysis of all the LPQ items simultaneously has never been reported. Rather, items within each subscale have been factor analysed to establish subscale unidimensionality and justify the use of composite subscale scores. It was of major interest to see if the six logically constructed items groups of the LPQ would be supported by empirical evidence. Additionally, it was of interest to compare the consistency of the reliability and correlational structure of the LPQ subscales in our study with those of previous cross-cultural studies. Confirmatory factor analysis was used to fit the six-factor item level model and to fit five representative subscale level factor models. A total of 1070 students between the ages of 15 to 18 years was drawn from a representative selection of 29 classes from within 15 secondary schools in Guangzhou, China. Males and females were almost equally represented. The six-factor item level model of the LPQ seemed to fit reasonably well, thus supporting the six dimensional structure of the LPQ and justifying the use of composite subscale scores for each LPQ dimension. However, the reliability of many of these subscales was low. Furthermore, only two subscale-level factor models showed marginally acceptable fit. Substantive considerations supported an oblique three-factor model. Because the LPQ subscales often show low internal consistency reliability, experimental and correlational studies that have used these subscales as dependent measures have been disappointing. It is suggested that some LPQ items should be revised and other items added to improve the inventory's overall psychometric properties.

  4. Diesel engine exhaust accelerates plaque formation in a mouse model of Alzheimer's disease.

    Science.gov (United States)

    Hullmann, Maja; Albrecht, Catrin; van Berlo, Damiën; Gerlofs-Nijland, Miriam E; Wahle, Tina; Boots, Agnes W; Krutmann, Jean; Cassee, Flemming R; Bayer, Thomas A; Schins, Roel P F

    2017-08-30

    Increasing evidence from toxicological and epidemiological studies indicates that the central nervous system is an important target for ambient air pollutants. We have investigated whether long-term inhalation exposure to diesel engine exhaust (DEE), a dominant contributor to particulate air pollution in urban environments, can aggravate Alzheimer's Disease (AD)-like effects in female 5X Familial AD (5XFAD) mice and their wild-type female littermates. Following 3 and 13 weeks exposures to diluted DEE (0.95 mg/m 3 , 6 h/day, 5 days/week) or clean air (controls) behaviour tests were performed and amyloid-β (Aβ) plaque formation, pulmonary histopathology and systemic inflammation were evaluated. In a string suspension task, assessing for grip strength and motor coordination, 13 weeks exposed 5XFAD mice performed significantly less than the 5XFAD controls. Spatial working memory deficits, assessed by Y-maze and X-maze tasks, were not observed in association with the DEE exposures. Brains of the 3 weeks DEE-exposed 5XFAD mice showed significantly higher cortical Aβ plaque load and higher whole brain homogenate Aβ42 levels than the clean air-exposed 5XFAD littermate controls. After the 13 weeks exposures, with increasing age and progression of the AD-phenotype of the 5XFAD mice, DEE-related differences in amyloid pathology were no longer present. Immunohistochemical evaluation of lungs of the mice revealed no obvious genetic background-related differences in tissue structure, and the DEE exposure did not cause histopathological changes in the mice of both backgrounds. Luminex analysis of plasma cytokines demonstrated absence of sustained systemic inflammation upon DEE exposure. Inhalation exposure to DEE causes accelerated plaque formation and motor function impairment in 5XFAD transgenic mice. Our study provides further support that the brain is a relevant target for the effects of inhaled DEE and suggests that long-term exposure to this ubiquitous air

  5. Emotional Dissonance and Sickness Absence Among Employees Working With Customers and Clients: A Moderated Mediation Model via Exhaustion and Human Resource Primacy.

    Science.gov (United States)

    Indregard, Anne-Marthe R; Ulleberg, Pål; Knardahl, Stein; Nielsen, Morten B

    2018-01-01

    Emotional dissonance, i.e., a discrepancy between required and felt emotions, has been established as a predictor of sickness absence in studies, but little is known about mechanisms that can explain this association. In order to prevent and reduce the impact of emotional dissonance on sickness absence, there is a need for greater attention to variables explaining when and how emotional dissonance is related to sickness absence. The overarching aim of this study was to examine whether emotional dissonance has an indirect association with sickness absence through exhaustion. In addition, we examined whether human resource primacy (HRP), which is the employer's degree of concern for human resources, moderates this indirect effect. A sample of 7758 employees, all working with customers and clients, were recruited from 96 Norwegian organizations. Emotional dissonance, exhaustion, and HRP were measured through surveys and then linked to registry data on medically certified sickness absence for the year following the survey assessment. Results showed that exhaustion is a mediator for the relationship between emotional dissonance and sickness absence. Furthermore, higher levels of HRP were found to reduce the positive association between emotional dissonance and exhaustion, and the indirect effect of emotional dissonance on sickness absence through exhaustion is found to be weaker when HRP is high. By testing this moderated mediation model, the current study contributes to the literature on emotion work by clarifying mechanisms that are crucial for the development of targeted interventions that aim to reduce and prevent sickness absence in client-driven work environments.

  6. Emotional Dissonance and Sickness Absence Among Employees Working With Customers and Clients: A Moderated Mediation Model via Exhaustion and Human Resource Primacy

    Science.gov (United States)

    Indregard, Anne-Marthe R.; Ulleberg, Pål; Knardahl, Stein; Nielsen, Morten B.

    2018-01-01

    Emotional dissonance, i.e., a discrepancy between required and felt emotions, has been established as a predictor of sickness absence in studies, but little is known about mechanisms that can explain this association. In order to prevent and reduce the impact of emotional dissonance on sickness absence, there is a need for greater attention to variables explaining when and how emotional dissonance is related to sickness absence. The overarching aim of this study was to examine whether emotional dissonance has an indirect association with sickness absence through exhaustion. In addition, we examined whether human resource primacy (HRP), which is the employer’s degree of concern for human resources, moderates this indirect effect. A sample of 7758 employees, all working with customers and clients, were recruited from 96 Norwegian organizations. Emotional dissonance, exhaustion, and HRP were measured through surveys and then linked to registry data on medically certified sickness absence for the year following the survey assessment. Results showed that exhaustion is a mediator for the relationship between emotional dissonance and sickness absence. Furthermore, higher levels of HRP were found to reduce the positive association between emotional dissonance and exhaustion, and the indirect effect of emotional dissonance on sickness absence through exhaustion is found to be weaker when HRP is high. By testing this moderated mediation model, the current study contributes to the literature on emotion work by clarifying mechanisms that are crucial for the development of targeted interventions that aim to reduce and prevent sickness absence in client-driven work environments. PMID:29670556

  7. Professional efficacy, exhaustion, and work characteristics among police officers: A longitudinal test of the learning-related predictions of the demand-control model

    NARCIS (Netherlands)

    Taris, T.W.; Kompier, M.A.J.; Geurts, S.A.E.; Houtman, I.L.D.; Heuvel, F.F.M. van den

    2010-01-01

    The present study addressed the relationships among professional efficacy, emotional exhaustion, and job characteristics (job demands and job control) in the context of a two-wave panel study among 828 Dutch police officers. Based on the demand-control model, we expected that high demands/high

  8. Model aerodynamic test results for two variable cycle engine coannular exhaust systems at simulated takeoff and cruise conditions. Comprehensive data report. Volume 1: Design layouts

    Science.gov (United States)

    Nelson, D. P.

    1981-01-01

    The design layouts and detailed design drawings of coannular exhaust nozzle models for a supersonic propulsion system are presented. The layout drawings show the assembly of the component parts for each configuration. A listing of the component parts is also given.

  9. Flowfield and Radiation Analysis of Missile Exhaust Plumes Using a Turbulent-Chemistry Interaction Model

    National Research Council Canada - National Science Library

    Calhoon, W. H; Kenzakowski, D. C

    2000-01-01

    ... components and missile defense systems. Current engineering level models neglect turbulent-chemistry interactions and typically underpredict the intensity of plume afterburning and afterburning burnout...

  10. Three dimensional model calculations of the global dispersion of high speed aircraft exhaust and implications for stratospheric ozone loss

    Science.gov (United States)

    Douglass, Anne R.; Rood, Richard B.; Jackman, Charles H.; Weaver, Clark J.

    1994-01-01

    Two-dimensional (zonally averaged) photochemical models are commonly used for calculations of ozone changes due to various perturbations. These include calculating the ozone change expected as a result of change in the lower stratospheric composition due to the exhaust of a fleet of supersonic aircraft flying in the lower stratosphere. However, zonal asymmetries are anticipated to be important to this sort of calculation. The aircraft are expected to be restricted from flying over land at supersonic speed due to sonic booms, thus the pollutant source will not be zonally symmetric. There is loss of pollutant through stratosphere/troposphere exchange, but these processes are spatially and temporally inhomogeneous. Asymmetry in the pollutant distribution contributes to the uncertainty in the ozone changes calculated with two dimensional models. Pollutant distributions for integrations of at least 1 year of continuous pollutant emissions along flight corridors are calculated using a three dimensional chemistry and transport model. These distributions indicate the importance of asymmetry in the pollutant distributions to evaluation of the impact of stratospheric aircraft on ozone. The implications of such pollutant asymmetries to assessment calculations are discussed, considering both homogeneous and heterogeneous reactions.

  11. Prediction model for exhausted point of ion exchange resin column of moderator purification circuit at Korean CANDU plant

    International Nuclear Information System (INIS)

    Sohn, Wook; Kang, Duck-Won; Ahn, Hyun Kyoung; Rhee, In Hyoung

    2005-01-01

    Most of the carbon-14 produced at CANDU plants are removed by an Ion eXchange (IX) resin column of the moderator purification circuit, and a column is replaced based on an empirical guideline. Since the amount of carbon-14 released from CANDU plants is governed by the performance of a column, optimal operation of IX resin columns through the timely replacement based on an objective criterion is very important. For this, the model for predicting the exhausted point of an IX resin column has been developed based on local chemical equilibrium. The performance evaluation at Wolsong Unit 3 showed that the model was able to simulate the removal of species by an IX resin column to such a high degree that the model could provide an objective criterion to replace an IX resin column timely. The derived maximum service time of a fresh IX resin column was 4,080 h, about twice that of the existing empirical guideline (up to 2,000h). Accordingly, if the maximum service time derived in this paper is applied to Wolsong Unit 3, it is expected to reduce the cost needed for the replacement of IX resin column by about 50%. (author)

  12. Dementia knowledge assessment scale (DKAS): confirmatory factor analysis and comparative subscale scores among an international cohort.

    Science.gov (United States)

    Annear, Michael J; Toye, Chris; Elliott, Kate-Ellen J; McInerney, Frances; Eccleston, Claire; Robinson, Andrew

    2017-07-31

    Dementia is a life-limiting condition that is increasing in global prevalence in line with population ageing. In this context, it is necessary to accurately measure dementia knowledge across a spectrum of health professional and lay populations with the aim of informing targeted educational interventions and improving literacy, care, and support. Building on prior exploratory analysis, which informed the development of the preliminarily valid and reliable version of the Dementia Knowledge Assessment Scale (DKAS), a Confirmatory Factor Analysis (CFA) was performed to affirm construct validity and proposed subscales to further increase the measure's utility for academics and educators. A large, de novo sample of 3649 volunteer respondents to a dementia-related online course was recruited to evaluate the performance of the DKAS and its proposed subscales. Respondents represented diverse cohorts, including health professionals, students, and members of the general public. Analyses included CFA (using structural equation modelling), measures of internal consistency (α), and non-parametric tests of subscale correlation (Spearman Correlation) and score differences between cohorts (Kruskal-Wallis one-way analysis of variance). Findings of the CFA supported a 25-item, four-factor model for the DKAS with two items removed due to poor performance and one item moved between factors. The resultant model exhibited good reliability (α = .85; ω h  = .87; overall scale), with acceptable subscale internal consistency (α ≥ .65; subscales). Subscales showed acceptable correlation without any indication of redundancy. Finally, total and DKAS subscale scores showed good discrimination between cohorts of respondents who would be anticipated to hold different levels of knowledge on the basis of education or experience related to dementia. The DKAS has been confirmed as a reliable and valid measure of dementia knowledge for diverse populations that is capable of elucidating

  13. Psychometric and Structural Analysis of the MMPI-2 Personality Psychopathology Five (PSY-5) Facet Subscales

    Science.gov (United States)

    Quilty, Lena C.; Bagby, R. Michael

    2007-01-01

    The Personality Psychopathology Five (PSY-5) is a model of personality psychopathology assessed in adult populations with a set of Minnesota Multiphasic Personality Inventory-2 (MMPI-2) scales. The authors examine the reliability and validity of recently developed lower-order facet subscales for each of these five domains, with an emphasis on…

  14. Emotional Exhaustion and Job Satisfaction in Airport Security Officers − Work−Family Conflict as Mediator in the Job Demands–Resources Model

    Directory of Open Access Journals (Sweden)

    Sophie eBaeriswyl

    2016-05-01

    Full Text Available The growing threat of terrorism has increased the importance of aviation security and the work of airport security officers (screeners. Nonetheless, airport security research has yet to focus on emotional exhaustion and job satisfaction as major determinants of screeners’ job performance. The present study bridges this research gap by applying the job demands–resources (JD−R model and using work–family conflict (WFC as an intervening variable to study relationships between work characteristics (workload and supervisor support, emotional exhaustion, and job satisfaction in 1,127 screeners at a European airport. Results of structural equation modeling revealed that (a supervisor support as a major job resource predicted job satisfaction among screeners; (b workload as a major job demand predicted their emotional exhaustion; and (c WFC proved to be a promising extension to the JD–R model that partially mediated the impact of supervisor support and workload on job satisfaction and emotional exhaustion. Theoretical and practical implications are discussed.

  15. Emotional Exhaustion and Job Satisfaction in Airport Security Officers – Work–Family Conflict as Mediator in the Job Demands–Resources Model

    Science.gov (United States)

    Baeriswyl, Sophie; Krause, Andreas; Schwaninger, Adrian

    2016-01-01

    The growing threat of terrorism has increased the importance of aviation security and the work of airport security officers (screeners). Nonetheless, airport security research has yet to focus on emotional exhaustion and job satisfaction as major determinants of screeners’ job performance. The present study bridges this research gap by applying the job demands–resources (JD–R) model and using work–family conflict (WFC) as an intervening variable to study relationships between work characteristics (workload and supervisor support), emotional exhaustion, and job satisfaction in 1,127 screeners at a European airport. Results of structural equation modeling revealed that (a) supervisor support as a major job resource predicted job satisfaction among screeners; (b) workload as a major job demand predicted their emotional exhaustion; and (c) WFC proved to be a promising extension to the JD–R model that partially mediated the impact of supervisor support and workload on job satisfaction and emotional exhaustion. Theoretical and practical implications are discussed. PMID:27242581

  16. Analyses of turbulent flow fields and aerosol dynamics of diesel engine exhaust inside two dilution sampling tunnels using the CTAG model.

    Science.gov (United States)

    Wang, Yan Jason; Yang, Bo; Lipsky, Eric M; Robinson, Allen L; Zhang, K Max

    2013-01-15

    Experimental results from laboratory emission testing have indicated that particulate emission measurements are sensitive to the dilution process of exhaust using fabricated dilution systems. In this paper, we first categorize the dilution parameters into two groups: (1) aerodynamics (e.g., mixing types, mixing enhancers, dilution ratios, residence time); and (2) mixture properties (e.g., temperature, relative humidity, particle size distributions of both raw exhaust and dilution gas). Then we employ the Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model to investigate the effects of those parameters on a set of particulate emission measurements comparing two dilution tunnels, i.e., a T-mixing lab dilution tunnel and a portable field dilution tunnel with a type of coaxial mixing. The turbulent flow fields and aerosol dynamics of particles are simulated inside two dilution tunnels. Particle size distributions under various dilution conditions predicted by CTAG are evaluated against the experimental data. It is found that in the area adjacent to the injection of exhaust, turbulence plays a crucial role in mixing the exhaust with the dilution air, and the strength of nucleation dominates the level of particle number concentrations. Further downstream, nucleation terminates and the growth of particles by condensation and coagulation continues. Sensitivity studies reveal that a potential unifying parameter for aerodynamics, i.e., the dilution rate of exhaust, plays an important role in new particle formation. The T-mixing lab tunnel tends to favor the nucleation due to a larger dilution rate of the exhaust than the coaxial mixing field tunnel. Our study indicates that numerical simulation tools can be potentially utilized to develop strategies to reduce the uncertainties associated with dilution samplings of emission sources.

  17. Numerical model of a thermoelectric generator with compact plate-fin heat exchanger for high temperature PEM fuel cell exhaust heat recovery

    DEFF Research Database (Denmark)

    Xin, Gao; Andreasen, Søren Juhl; Chen, Min

    2012-01-01

    on a finite-element approach. On each discretized segment, fluid properties, heat transfer process and TEG performance are locally calculated for higher model precision. To benefit both the system design and fabrication, the way to model TEG modules is herein reconsidered; a database of commercialized compact......This paper presents a numerical model of an exhaust heat recovery system for a high temperature polymer electrolyte membrane fuel cell (HTPEMFC) stack. The system is designed as thermoelectric generators (TEGs) sandwiched in the walls of a compact plate-fin heat exchanger. Its model is based...... plate-fin heat exchangers is adopted. Then the model is validated against experimental data and the main variables are identified by means of a sensitivity analysis. Finally, the system configuration is optimized for recovering heat from the exhaust gas. The results exhibit the crucial importance...

  18. A model study of the size and composition distribution of aerosols in an aircraft exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Sorokin, A.A. [SRC `ECOLEN`, Moscow (Russian Federation)

    1997-12-31

    A two-dimensional, axisymmetric flow field model which includes water and sulphate aerosol formation represented by moments of the size and composition distribution function is used to calculate the effect of radial turbulent jet mixing on the aerosol size distribution and mean modal composition. (author) 6 refs.

  19. Control-Oriented Model of Molar Scavenge Oxygen Fraction for Exhaust Recirculation in Large Diesel Engines

    DEFF Research Database (Denmark)

    Nielsen, Kræn Vodder; Blanke, Mogens; Eriksson, Lars

    2016-01-01

    the behavior of the scavenge oxygen fraction well over the entire envelope of load and blower speed range that are relevant for EGR. The simplicity of the new model makes it suitable for observer and control design, which are essential steps to meet the emission requirements for marine diesel engines that take...

  20. A model study of the size and composition distribution of aerosols in an aircraft exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Sorokin, A A [SRC ` ECOLEN` , Moscow (Russian Federation)

    1998-12-31

    A two-dimensional, axisymmetric flow field model which includes water and sulphate aerosol formation represented by moments of the size and composition distribution function is used to calculate the effect of radial turbulent jet mixing on the aerosol size distribution and mean modal composition. (author) 6 refs.

  1. CXCR4 blockade decreases CD4+ T cell exhaustion and improves survival in a murine model of polymicrobial sepsis.

    Science.gov (United States)

    Ramonell, Kimberly M; Zhang, Wenxiao; Hadley, Annette; Chen, Ching-Wen; Fay, Katherine T; Lyons, John D; Klingensmith, Nathan J; McConnell, Kevin W; Coopersmith, Craig M; Ford, Mandy L

    2017-01-01

    Sepsis is a dysregulated systemic response to infection involving many inflammatory pathways and the induction of counter-regulatory anti-inflammatory processes that results in a state of immune incompetence and can lead to multi-organ failure. CXCR4 is a chemokine receptor that, following ligation by CXCL12, directs cells to bone marrow niches and also plays an important role in T cell cosignaling and formation of the immunological synapse. Here, we investigated the expression and function of CXCR4 in a murine model of polymicrobial sepsis. Results indicate that CXCR4 is selectively upregulated on naïve CD4+ and CD8+ T cells and CD4+ central memory T cells following the induction of sepsis, and that CXCR4 antagonism resulted in a significant decrease in sepsis-induced mortality. We probed the mechanistic basis for these findings and found that CXCR4 antagonism significantly increased the number of peripheral CD4+ and CD8+ T cells following sepsis. Moreover, mice treated with the CXCR4 antagonist contained fewer PD-1+ LAG-3+ 2B4+ cells, suggesting that blockade of CXCR4 mitigates CD4+ T cell exhaustion during sepsis. Taken together, these results characterize CXCR4 as an important pathway that modulates immune dysfunction and mortality following sepsis, which may hold promise as a target for future therapeutic intervention in septic patients.

  2. CXCR4 blockade decreases CD4+ T cell exhaustion and improves survival in a murine model of polymicrobial sepsis.

    Directory of Open Access Journals (Sweden)

    Kimberly M Ramonell

    Full Text Available Sepsis is a dysregulated systemic response to infection involving many inflammatory pathways and the induction of counter-regulatory anti-inflammatory processes that results in a state of immune incompetence and can lead to multi-organ failure. CXCR4 is a chemokine receptor that, following ligation by CXCL12, directs cells to bone marrow niches and also plays an important role in T cell cosignaling and formation of the immunological synapse. Here, we investigated the expression and function of CXCR4 in a murine model of polymicrobial sepsis. Results indicate that CXCR4 is selectively upregulated on naïve CD4+ and CD8+ T cells and CD4+ central memory T cells following the induction of sepsis, and that CXCR4 antagonism resulted in a significant decrease in sepsis-induced mortality. We probed the mechanistic basis for these findings and found that CXCR4 antagonism significantly increased the number of peripheral CD4+ and CD8+ T cells following sepsis. Moreover, mice treated with the CXCR4 antagonist contained fewer PD-1+ LAG-3+ 2B4+ cells, suggesting that blockade of CXCR4 mitigates CD4+ T cell exhaustion during sepsis. Taken together, these results characterize CXCR4 as an important pathway that modulates immune dysfunction and mortality following sepsis, which may hold promise as a target for future therapeutic intervention in septic patients.

  3. Off-design dynamic model of a real Organic Rankine Cycle system fuelled by exhaust gases from industrial processes

    International Nuclear Information System (INIS)

    Mazzi, N.; Rech, S.; Lazzaretto, A.

    2015-01-01

    ORCs (Organic Rankine Cycles) represent an effective option to exploit low grade heat fluxes, the characteristics of which not only affect design, but also performance and stability during operation. This paper presents a detailed design and off-design dynamic model of a superheated regenerative ORC system using the exhaust gases of an industrial process. The point of view is that of a designer who has to predict the system behavior both at steady-state and transient operation to get a reliable and efficient operation. Real physical and operating characteristics of all components are considered, with particular attention to the geometries of shell-and-tube commercial heat exchangers to properly simulate mass and thermal inertias. A suitable control system is chosen to govern the off-design operation taking into account all real operating constraints. Results show a slight decrease in gross system efficiency (less than 1% point) either varying the oil mass flow rate (in the range 80–110%) at constant temperature of the cold sink or this temperature (of 10 °C) at constant oil mass flow rate. Simulation of the transient behavior demonstrates the effectiveness of the control system on ORC stability under variation of the hot source mass flow rate and cold sink temperature. - Highlights: • A detailed off-design dynamic model of a regenerative ORC system is presented. • The model includes real geometries of commercial shell-and-tube heat exchangers. • High efficiency of the ORC system is obtained at partial load in the range 80–110%. • Variations of the evaporator volume does not significantly affect system stability.

  4. Effects of cognitive stimulation with a self-modeling video on time to exhaustion while running at maximal aerobic velocity: a pilot study.

    Science.gov (United States)

    Hagin, Vincent; Gonzales, Benoît R; Groslambert, Alain

    2015-04-01

    This study assessed whether video self-modeling improves running performance and influences the rate of perceived exertion and heart rate response. Twelve men (M age=26.8 yr., SD=6; M body mass index=22.1 kg.m(-2), SD=1) performed a time to exhaustion running test at 100 percent maximal aerobic velocity while focusing on a video self-modeling loop to synchronize their stride. Compared to the control condition, there was a significant increase of time to exhaustion. Perceived exertion was lower also, but there was no significant change in mean heart rate. In conclusion, the video self-modeling used as a pacer apparently increased endurance by decreasing perceived exertion without affecting the heart rate.

  5. Effects of Subscale Size and Shape on Global Energy Dissipation in a Multiscale Model of a Fiber-Reinforced Composite Exhibiting Post-Peak Strain Softening Using Abaqus and FEAMAC

    Science.gov (United States)

    Pineda, Evan, J.; Bednarcyk, Brett, A.; Arnold, Steven, M.

    2012-01-01

    A mesh objective crack band model is implemented in the generalized method of cells (GMC) micromechanics model to predict failure of a composite repeating unit cell (RUC). The micromechanics calculations are achieved using the MAC/GMC core engine within the ImMAC suite of micromechanics codes, developed at the NASA Glenn Research Center. The microscale RUC is linked to a macroscale Abaqus/Standard finite element model using the FEAMAC multiscale framework (included in the ImMAC suite). The effects of the relationship between the characteristic length of the finite element and the size of the microscale RUC on the total energy dissipation of the multiscale model are investigated. A simple 2-D composite square subjected to uniaxial tension is used to demonstrate the effects of scaling the dimensions of the RUC such that the length of the sides of the RUC are equal to the characteristic length of the finite element. These results are compared to simulations where the size of the RUC is fixed, independent of the element size. Simulations are carried out for a variety of mesh densities and element shapes, including square and triangular. Results indicate that a consistent size and shape must be used to yield preserve energy dissipation across the scales.

  6. Subscale Water Based Phase Change Material Heat Exchanger Development

    Science.gov (United States)

    Sheth, Rubik; Hansen, Scott

    2016-01-01

    Supplemental heat rejection devices are required in many spacecraft as the radiators are not sized to meet the full heat rejection demand. One means of obtaining additional heat rejection is through the use of phase change material heat exchangers (PCM HX's). PCM HX's utilize phase change to store energy in unfavorable thermal environments (melting) and reject the energy in favorable environments (freezing). Traditionally, wax has been used as a PCM on spacecraft. However, water is an attractive alternative because it is capable of storing about 40% more energy per unit mass due to its higher latent heat of fusion. The significant problem in using water as a PCM is its expansion while freezing, leading to structural integrity concerns when housed in an enclosed heat exchanger volume. Significant investigation and development has taken place over the past five years to understand and overcome the problems associated with water PCM HX's. This paper reports on the final efforts by Johnson Space Center's Thermal Systems Branch to develop a water based PCM HX. The test article developed and reported on is a subscale version of the full-scale water-based PCM HX's constructed by Mezzo Technologies. The subscale unit was designed by applying prior research on freeze front propagation and previous full-scale water PCM HX development. Design modifications to the subscale unit included use of urethane bladder, decreased aspect ratio, perforated protection sheet, and use of additional mid-plates. Testing of the subscale unit was successful and 150 cycles were completed without fail.

  7. Design and Test of a Nb3Sn Subscale Dipole Magnet for Training Studies

    International Nuclear Information System (INIS)

    Felice, Helene; Caspi, Shlomo; Dietderich, Daniel R.; Felice, Helene; Ferracin, Paolo; Gourlay, Steve A.; Hafalia, Aurelo R.; Lietzke, Alan F.; Mailfert, Alain; Sabbi, GainLuca; Vedrine, Pierre

    2007-01-01

    As part of a collaboration between CEA/Saclay and the Superconducting Magnet Group at LBNL, a subscale dipole structure has been developed to study training in Nb3Sn coils under variable pre-stress conditions. This design is derived from the LBNL Subscale Magnet and relies on the use of identical Nb 3 Sn racetrack coils. Whereas the original LBNL subscale magnet was in a dual bore 'common-coil' configuration, the new subscale dipole magnet (SD) is assembled as a single bore dipole made of two superposed racetrack coils. The dipole is supported by a new mechanical structure developed to withstand the horizontal and axial Lorentz forces and capable of applying variable vertical, horizontal and axial preload. The magnet was tested at LBNL as part of a series of training studies aiming at understanding of the relation between pre-stress and magnet performance. Particular attention is given to the coil ends where the magnetic field peaks and stress conditions are the least understood. After a description of SD design, assembly, cool-down and tests results are reported and compared with the computations of the OPERA3D and ANSYS magnetic and mechanical models

  8. Sub-scale Inverse Wind Turbine Blade Design Using Bound Circulation

    Science.gov (United States)

    Kelley, Christopher; Berg, Jonathan

    2014-11-01

    A goal of the National Rotor Testbed project at Sandia is to design a sub-scale wind turbine blade that has similitude to a modern, commercial size blade. However, a smaller diameter wind turbine operating at the same tip-speed-ratio exhibits a different range of operating Reynolds numbers across the blade span, thus changing the local lift and drag coefficients. Differences to load distribution also affect the wake dynamics and stability. An inverse wind turbine blade design tool has been implemented which uses a target, dimensionless circulation distribution from a full-scale blade to find the chord and twist along a sub-scale blade. In addition, airfoil polar data are interpolated from a few specified span stations leading to a smooth, manufacturable blade. The iterative process perturbs chord and twist, after running a blade element momentum theory code, to reduce the residual sum of the squares between the modeled sub-scale circulation and the target full-scale circulation. It is shown that the converged sub-scale design also leads to performance similarity in thrust and power coefficients. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy under Contract DE-AC04-94AL85000.

  9. Study on calculation models and distribution rules of the radon concentration and its progenies concentration in blind roadway with forced-exhaust ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Wang Liheng; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Wang Shuyun; Ding Dexin

    2014-01-01

    The forced-exhaust ventilation is an important way to control the concentration of radon and its progenies in long-distance blind driving roadway. It is of great significance for guiding the design of ventilation and radiation protection to study distribution characteristics of the concentration of radon and its progenies in the wind of roadway adopting the forced-exhaust ventilation. Therefore, according to the decay relationship of radon and its progenies, a simplified mathematical calculation model was built, which relates to the radon activity concentration and the potential alpha concentration of radon progenies. The paper also analyzed the sources of radon and its progenies in the limited space of the blind roadway. Then, based on the turbulence mass transfer theory of ventilation air flow, the paper established mathematical calculation models of distribution characteristics of the radon activity concentration and the potential alpha concentration of radon progenies in blind roadway with forced-exhaust ventilation, respectively. Finally, the paper applied the calculation models to a special blind roadway, and discussed the influence of the ventilation air inflow and the radon exhalation rate of rock wall on the distribution of radon concentration and the potential alpha concentration of radon progenies in the roadway. Meanwhile, some protective measurements were put forward to reduce the radiation dose of worker caused by radon and its progenies in the blind roadway. (authors)

  10. Portable Exhauster Position Paper

    International Nuclear Information System (INIS)

    KRISKOVICH, J.R.

    1999-01-01

    This document identifies the tasks that are involved in preparing the ''standby'' portable exhauster to support Interim Stabilization's schedule for saltwell pumping. A standby portable exhaust system will be assigned to any facility scheduled to be saltwell pumped with the exception of 241-S farm, 241-SX farm or 241-T farm. The standby portable exhauster shall be prepared for use and placed in storage. The standby portable exhaust system shall be removed from storage and installed to ventilate tanks being pumped that reach 25% LFL. There are three tasks that are evaluated in this document. Each task shall be completed to support portable exhaust system installation and operation. They are: Pre Installation Task; Portable Exhaust System Storage Task; and Portable Exhaust System Installation and Operation Task

  11. PIXE analysis of vehicle exhaust particulate

    International Nuclear Information System (INIS)

    Shi Xianfeng; Yao Huiying; Liu Bo; Sun Minde; Xu Huawei; Mi Yong; Shen Hao

    2001-01-01

    PIXE technique on the analysis of vehicle exhaust particulate is introduced. The clement composition and concentration of particulate are obtained. Some elements which are related to environmental pollution such as sulfur lead, silicon and manganese, were analyzed and discussed in detail by PIXE technique Nowadays although unleaded gasoline is widely used, the lead concentration is still very high in exhaust particulate. The concentrations of silicon and manganese in exhaust particulate from different model vehicles are also quite high from measurements. It shows that an evidence for exhaust pollution control could be provided from this work

  12. Energy Cascade Analysis: from Subscale Eddies to Mean Flow

    Science.gov (United States)

    Cheikh, Mohamad Ibrahim; Wonnell, Louis; Chen, James

    2017-11-01

    Understanding the energy transfer between eddies and mean flow can provide insights into the energy cascade process. Much work has been done to investigate the energy cascade at the level of the smallest eddies using different numerical techniques derived from the Navier-Stokes equations. These methodologies, however, prove to be computationally inefficient when producing energy spectra for a wide range of length scales. In this regard, Morphing Continuum Theory (MCT) resolves the length-scales issues by assuming the fluid continuum to be composed of inner structures that play the role of subscale eddies. The current study show- cases the capabilities of MCT in capturing the dynamics of energy cascade at the level of subscale eddies, through a supersonic turbulent flow of Mach 2.93 over an 8× compression ramp. Analysis of the results using statistical averaging procedure shows the existence of a statistical coupling of the internal and translational kinetic energy fluctuations with the corresponding rotational kinetic energy of the subscale eddies, indicating a multiscale transfer of energy. The results show that MCT gives a new characterization of the energy cascade within compressible turbulence without the use of excessive computational resources. This material is based upon work supported by the Air Force Office of Scientific Research under Award Number FA9550-17-1-0154.

  13. Kryptonate-based instrumentation development for automobile exhaust pollutants. Phase III report: design and construction of four (4) experimental models

    International Nuclear Information System (INIS)

    Goodman, P.; Donaghue, T.

    This phase of the program encompasses the design, construction and evaluation of four (4) prototype instruments for the detection of automobile exhaust pollutant. These instruments employ the radio release mechanism utilized by Panametrics in detection of various trace gases. The prototype instruments are of two (2) designs. One design is operable from a power source supplied by an automobile battery. The second design is operable from 110 volts AC power. Successful evaluation in the laboratory as well as with various automobiles were performed with both type instruments. Scale-up of the quantity of sensor material prepared introduced unexpected problems with respect to detection lifetime which were not satisfactorily resolved within the time and funds available to the program. Nevertheless, a Kryptonate-based instrument using a single detection method for the measurement of hydrocarbons, CO and NO/sub x/ as pollutants by automobile exhausts was shown to be operable with actual automobile exhausts, to provide more than adequate sensitivity for inspection purposes, and to provide response and recovery times for full scale reading in the range 10-15 secs. (auth)

  14. Analytical and numerical models for estimating the effect of exhaust ventilation on radon entry in houses with basements or crawl spaces

    International Nuclear Information System (INIS)

    Mowris, R.J.

    1986-08-01

    Mechanical exhaust ventilation systems are being installed in newer, energy-efficient houses and their operation can increase the indoor-outdoor pressure differences that drive soil gas and thus radon entry. This thesis presents simplified models for estimating the pressure driven flow of radon into houses with basements or crawl spaces, due to underpressures induced by indoor-outdoor temperature differences, wind, or exhaust ventilation. A two-dimensional finite difference model is presented and used to calculate the pressure field and soil gas flow rate into a basement situated in soil of uniform permeability. A simplified analytical model is compared to the finite difference model with generally very good agreement. Another simplified model is presented for houses with a crawl space. Literature on radon research is also reviewed to show why pressure driven flow of soil gas is considered to be the major source of radon entry in houses with higher-than-average indoor radon concentrations. Comparisons of measured vs. calculated indoor radon concentrations for a house with a basement showed the simplified basement model underpredicting on average by 25%. For a house with a crawl space the simplified crawl space model overpredicted by 23% when the crawl space vents are open and 48% when the crawl space vents are sealed

  15. Subscale Flight Testing for Aircraft Loss of Control: Accomplishments and Future Directions

    Science.gov (United States)

    Cox, David E.; Cunningham, Kevin; Jordan, Thomas L.

    2012-01-01

    Subscale flight-testing provides a means to validate both dynamic models and mitigation technologies in the high-risk flight conditions associated with aircraft loss of control. The Airborne Subscale Transport Aircraft Research (AirSTAR) facility was designed to be a flexible and efficient research facility to address this type of flight-testing. Over the last several years (2009-2011) it has been used to perform 58 research flights with an unmanned, remotely-piloted, dynamically-scaled airplane. This paper will present an overview of the facility and its architecture and summarize the experimental data collected. All flights to date have been conducted within visual range of a safety observer. Current plans for the facility include expanding the test volume to altitudes and distances well beyond visual range. The architecture and instrumentation changes associated with this upgrade will also be presented.

  16. Exhaustion from prolonged gambling

    Directory of Open Access Journals (Sweden)

    Fatimah Lateef

    2013-01-01

    Full Text Available Complaints of fatigue and physical exhaustion are frequently seen in the acute medical setting, especially amongst athletes, army recruits and persons involved in strenuous and exertional physical activities. Stress-induced exhaustion, on the other hand, is less often seen, but can present with very similar symptoms to physical exhaustion. Recently, three patients were seen at the Department of Emergency Medicine, presenting with exhaustion from prolonged involvement in gambling activities. The cases serve to highlight some of the physical consequences of prolonged gambling.

  17. Respiratory hazard assessment of combined exposure to complete gasoline exhaust and respirable volcanic ash in a multicellular human lung model at the air-liquid interface

    Science.gov (United States)

    Tomasek, Ines; Horwell, Claire J.; Bisig, Christoph; Damby, David; Comte, Pierre; Czerwinski, Jan; Petri-Fink, Alke; Clift, Martin J D; Drasler, Barbara; Rothen-Rutishauer, Barbara

    2018-01-01

    Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases. It is further postulated similar exposure to volcanic ash can also affect such disease states. Understanding of the impact of combined exposure of volcanic ash and anthropogenic pollution to human health, however, remains limited.The aim of this study was to assess the biological impact of combined exposure to respirable volcanic ash (from Soufrière Hills volcano (SHV), Montserrat and Chaitén volcano (ChV), Chile; representing different magmatic compositions and eruption styles) and freshly-generated complete exhaust from a gasoline vehicle. A multicellular human lung model (an epithelial cell-layer composed of A549 alveolar type II-like cells complemented with human blood monocyte-derived macrophages and dendritic cells cultured at the air-liquid interface) was exposed to diluted exhaust (1:10) continuously for 6 h, followed by immediate exposure to the ash as a dry powder (0.54 ± 0.19 μg/cm2 and 0.39 ± 0.09 μg/cm2 for SHV and ChV ash, respectively). After an 18 h incubation, cells were exposed again for 6 h to diluted exhaust, and a final 18 h incubation (at 37 °C and 5% CO2). Cell cultures were then assessed for cytotoxic, oxidative stress and (pro-)inflammatory responses.Results indicate that, at all tested (sub-lethal) concentrations, co-exposures with both ash samples induced no significant expression of genes associated with oxidative stress (HMOX1, NQO1) or production of (pro-)inflammatory markers (IL-1β, IL-8, TNF-α) at the gene and protein levels. In summary, considering the employed experimental conditions, combined exposure of

  18. Respiratory hazard assessment of combined exposure to complete gasoline exhaust and respirable volcanic ash in a multicellular human lung model at the air-liquid interface.

    Science.gov (United States)

    Tomašek, Ines; Horwell, Claire J; Bisig, Christoph; Damby, David E; Comte, Pierre; Czerwinski, Jan; Petri-Fink, Alke; Clift, Martin J D; Drasler, Barbara; Rothen-Rutishauser, Barbara

    2018-07-01

    Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases. It is further postulated similar exposure to volcanic ash can also affect such disease states. Understanding of the impact of combined exposure of volcanic ash and anthropogenic pollution to human health, however, remains limited. The aim of this study was to assess the biological impact of combined exposure to respirable volcanic ash (from Soufrière Hills volcano (SHV), Montserrat and Chaitén volcano (ChV), Chile; representing different magmatic compositions and eruption styles) and freshly-generated complete exhaust from a gasoline vehicle. A multicellular human lung model (an epithelial cell-layer composed of A549 alveolar type II-like cells complemented with human blood monocyte-derived macrophages and dendritic cells cultured at the air-liquid interface) was exposed to diluted exhaust (1:10) continuously for 6 h, followed by immediate exposure to the ash as a dry powder (0.54 ± 0.19 μg/cm 2 and 0.39 ± 0.09 μg/cm 2 for SHV and ChV ash, respectively). After an 18 h incubation, cells were exposed again for 6 h to diluted exhaust, and a final 18 h incubation (at 37 °C and 5% CO 2 ). Cell cultures were then assessed for cytotoxic, oxidative stress and (pro-)inflammatory responses. Results indicate that, at all tested (sub-lethal) concentrations, co-exposures with both ash samples induced no significant expression of genes associated with oxidative stress (HMOX1, NQO1) or production of (pro-)inflammatory markers (IL-1β, IL-8, TNF-α) at the gene and protein levels. In summary, considering the employed experimental conditions, combined exposure of

  19. Exploring the dimensionality of the Originality subscale of the Kirton Adaption-Innovation Inventory.

    Science.gov (United States)

    Im, Subin; Hu, Michael Y; Toh, Rex S

    2003-12-01

    The Kirton Adaption-Innovation Inventory, which is a widely used measure of innovative (as opposed to adaptive) cognitive individual style, is believed to have three dimensions: Sufficiency of Originality, Efficiency, and Rule/Group Conformity. Several studies have raised concerns regarding its construct validity, specifically with respect to the Sufficiency of Originality subscale. Within this subscale, exploratory factor analysis identified two distinct subdimensions, Idea Generation and Preference for Change. In this study, we used a sample of 356 household participants (with an average age of 56 yr., average income of 39,700 dollars, and average of 15 yr. of education) from the Arkansas Household Research Panel. We then employed Bollen and Grandjean's approach based on confirmatory factor analysis to assess whether there are actually two distinct subdimensions instead of one. Our study shows that within the Sufficiency of Originality subscale, there are indeed two distinct subdimensions, Idea Generation and Preference for Change. Further analyses indicate that dropping double-loaded items identified through exploratory factor analysis significantly improves the fit statistics. Also, allowing correlated errors for the measurement items that belong to the same subdimension can also significantly improve the overall fit of the model based on chi-square statistics.

  20. Unemployment Benefit Exhaustion

    DEFF Research Database (Denmark)

    Filges, Trine; Pico Geerdsen, Lars; Knudsen, Anne-Sofie Due

    2015-01-01

    This systematic review studied the impact of exhaustion of unemployment benefits on the exit rate out of unemployment and into employment prior to benefit exhaustion or shortly thereafter. Method: We followed Campbell Collaboration guidelines to prepare this review, and ultimately located 12...

  1. Duplex tab exhaust nozzle

    Science.gov (United States)

    Gutmark, Ephraim Jeff (Inventor); Martens, Steven (nmn) (Inventor)

    2012-01-01

    An exhaust nozzle includes a conical duct terminating in an annular outlet. A row of vortex generating duplex tabs are mounted in the outlet. The tabs have compound radial and circumferential aft inclination inside the outlet for generating streamwise vortices for attenuating exhaust noise while reducing performance loss.

  2. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R C; Anderson, M R; Miake-Lye, R C; Kolb, C E [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A A; Buriko, Y I [Scientific Research Center ` Ecolen` , Moscow (Russian Federation)

    1998-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  3. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Anderson, M.R.; Miake-Lye, R.C.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A.A.; Buriko, Y.I. [Scientific Research Center `Ecolen`, Moscow (Russian Federation)

    1997-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  4. Active Piezoelectric Vibration Control of Subscale Composite Fan Blades

    Science.gov (United States)

    Duffy, Kirsten P.; Choi, Benjamin B.; Provenza, Andrew J.; Min, James B.; Kray, Nicholas

    2012-01-01

    As part of the Fundamental Aeronautics program, researchers at NASA Glenn Research Center (GRC) are investigating new technologies supporting the development of lighter, quieter, and more efficient fans for turbomachinery applications. High performance fan blades designed to achieve such goals will be subjected to higher levels of aerodynamic excitations which could lead to more serious and complex vibration problems. Piezoelectric materials have been proposed as a means of decreasing engine blade vibration either through a passive damping scheme, or as part of an active vibration control system. For polymer matrix fiber composite blades, the piezoelectric elements could be embedded within the blade material, protecting the brittle piezoceramic material from the airflow and from debris. To investigate this idea, spin testing was performed on two General Electric Aviation (GE) subscale composite fan blades in the NASA GRC Dynamic Spin Rig Facility. The first bending mode (1B) was targeted for vibration control. Because these subscale blades are very thin, the piezoelectric material was surface-mounted on the blades. Three thin piezoelectric patches were applied to each blade two actuator patches and one small sensor patch. These flexible macro-fiber-composite patches were placed in a location of high resonant strain for the 1B mode. The blades were tested up to 5000 rpm, with patches used as sensors, as excitation for the blade, and as part of open- and closed-loop vibration control. Results show that with a single actuator patch, active vibration control causes the damping ratio to increase from a baseline of 0.3% critical damping to about 1.0% damping at 0 RPM. As the rotor speed approaches 5000 RPM, the actively controlled blade damping ratio decreases to about 0.5% damping. This occurs primarily because of centrifugal blade stiffening, and can be observed by the decrease in the generalized electromechanical coupling with rotor speed.

  5. Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi, E-mail: ysekine@waseda.jp [Department of Applied Chemistry, Waseda University, 65-301, Okubo, Shinjuku, Tokyo 169-8555 (Japan)

    2011-07-13

    Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C{sub 2} hydrocarbon without coke formation at a ratio of CO{sub 2}/C{sub fuel} = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

  6. Modeling the selective catalytic reduction of NOx by ammonia over a Vanadia-based catalyst from heavy duty diesel exhaust gases

    International Nuclear Information System (INIS)

    Yun, Byoung Kyu; Kim, Man Young

    2013-01-01

    A numerical simulation for prediction of NO X conversion over a commercial V 2 O 5 catalyst with NH 3 as a reductant was performed for a heavy duty diesel engine applications. The chemical behaviors of the SCR reactor are described by using the global NO X kinetics including standard, fast, and NH 3 oxidation reactions with the Langmuir–Hinshelwood (LH) mechanism incorporated into the commercial Boost code. After introducing mathematical models for the SCR reaction with specific reaction parameters, the effects of various parameters such as space velocities, the O 2 , H 2 O, NO 2 , and NH 3 concentrations on the NOx conversion are thoroughly studied and validated by comparing with the experimental data available in the literature. It is found that NO X conversion increases with decreasing space velocity, H 2 O concentration, and NH 3 /NO X ratio, and increasing O 2 concentration and NO 2 /NO X ratio. The study shows that not only is the present approach adopted is flexible in treating performance of the commercial V 2 O 5 based SCR catalyst, it is also accurate and efficient for the prediction of NO X conversion in diesel exhaust environments. - Highlights: ► To find the reaction parameters for LH mechanism over a commercial V2O5 catalyst. ► To investigate the effects of various parameters on the SCR NO X conversion. ► To present benchmark solutions on SCR behavior with diesel exhaust environments.

  7. Exhaustive Classification of the Invariant Solutions for a Specific Nonlinear Model Describing Near Planar and Marginally Long-Wave Unstable Interfaces for Phase Transition

    Science.gov (United States)

    Ahangari, Fatemeh

    2018-05-01

    Problems of thermodynamic phase transition originate inherently in solidification, combustion and various other significant fields. If the transition region among two locally stable phases is adequately narrow, the dynamics can be modeled by an interface motion. This paper is devoted to exhaustive analysis of the invariant solutions for a modified Kuramoto-Sivashinsky equation in two spatial and one temporal dimensions is presented. This nonlinear partial differential equation asymptotically characterizes near planar interfaces, which are marginally long-wave unstable. For this purpose, by applying the classical symmetry method for this model the classical symmetry operators are attained. Moreover, the structure of the Lie algebra of symmetries is discussed and the optimal system of subalgebras, which yields the preliminary classification of group invariant solutions is constructed. Mainly, the Lie invariants corresponding to the infinitesimal symmetry generators as well as associated similarity reduced equations are also pointed out. Furthermore, the nonclassical symmetries of this nonlinear PDE are also comprehensively investigated.

  8. Modelling how reversal of immune exhaustion elicits cure of chronic hepatitis C after the end of treatment with direct-acting antiviral agents.

    Science.gov (United States)

    Baral, Subhasish; Roy, Rahul; Dixit, Narendra M

    2018-05-09

    A fraction of chronic hepatitis C patients treated with direct-acting antivirals (DAAs) achieved sustained virological responses (SVR), or cure, despite having detectable viremia at the end of treatment (EOT). This observation, termed EOT + /SVR, remains puzzling and precludes rational optimization of treatment durations. One hypothesis to explain EOT + /SVR, the immunologic hypothesis, argues that the viral decline induced by DAAs during treatment reverses the exhaustion of cytotoxic T lymphocytes (CTLs), which then clear the infection after treatment. Whether the hypothesis is consistent with data of viral load changes in patients who experienced EOT + /SVR is unknown. Here, we constructed a mathematical model of viral kinetics incorporating the immunologic hypothesis and compared its predictions with patient data. We found the predictions to be in quantitative agreement with patient data. Using the model, we unraveled an underlying bistability that gives rise to EOT + /SVR and presents a new avenue to optimize treatment durations. Infected cells trigger both activation and exhaustion of CTLs. CTLs in turn kill infected cells. Due to these competing interactions, two stable steady states, chronic infection and viral clearance, emerge, separated by an unstable steady state with intermediate viremia. When treatment during chronic infection drives viremia sufficiently below the unstable state, spontaneous viral clearance results post-treatment, marking EOT + /SVR. The duration to achieve this desired reduction in viremia defines the minimum treatment duration required for ensuring SVR, which our model can quantify. Estimating parameters defining the CTL response of individuals to HCV infection would enable the application of our model to personalize treatment durations. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Phenotypic T cell exhaustion in a murine model of bacterial infection in the setting of pre-existing malignancy.

    Directory of Open Access Journals (Sweden)

    Rohit Mittal

    Full Text Available While much of cancer immunology research has focused on anti-tumor immunity both systemically and within the tumor microenvironment, little is known about the impact of pre-existing malignancy on pathogen-specific immune responses. Here, we sought to characterize the antigen-specific CD8+ T cell response following a bacterial infection in the setting of pre-existing pancreatic adenocarcinoma. Mice with established subcutaneous pancreatic adenocarcinomas were infected with Listeria monocytogenes, and antigen-specific CD8+ T cell responses were compared to those in control mice without cancer. While the kinetics and magnitude of antigen-specific CD8+ T cell expansion and accumulation was comparable between the cancer and non-cancer groups, bacterial antigen-specific CD8+ T cells and total CD4+ and CD8+ T cells in cancer mice exhibited increased expression of the coinhibitory receptors BTLA, PD-1, and 2B4. Furthermore, increased inhibitory receptor expression was associated with reduced IFN-γ and increased IL-2 production by bacterial antigen-specific CD8+ T cells in the cancer group. Taken together, these data suggest that cancer's immune suppressive effects are not limited to the tumor microenvironment, but that pre-existing malignancy induces phenotypic exhaustion in T cells by increasing expression of coinhibitory receptors and may impair pathogen-specific CD8+ T cell functionality and differentiation.

  10. Multidimensional modeling of the effect of Exhaust Gas Recirculation (EGR) on exergy terms in an HCCI engine fueled with a mixture of natural gas and diesel

    International Nuclear Information System (INIS)

    Jafarmadar, Samad; Nemati, Peyman; Khodaie, Rana

    2015-01-01

    Highlights: • The exergy efficiency decreases by 41.3%. • The irreversibility increases by 46.80%. • The cumulative heat loss exergy decreases by 68.10%. • The cumulative work exergy decreases by 63.4%. • The exhaust losses exergy increases by 28.79%. - Abstract: One of the most important issues in HCCI engines is auto-ignition timing control. EGR introduction into intake charge can be a method to control combustion phasing and its duration. In the current study, a FORTRAN-based code which includes 10 species (O_2, N_2, H_2O, CO_2, CO, H_2, OH, O, N, NO) associated with combustion products was employed to study the exergy analysis in a dual fuel (natural gas + diesel) HCCI engine at four EGR (exhaust gas recirculation) mass fractions (0%, 10%, 20%, and 30%) while the diesel fuel amount was held constant. In order to achieve this task, a 3-D CFD code was employed to model the energy balance during a closed cycle of running engine simulation. Moreover, an efficient Extend Coherent Flame Model-Three Zone model (ECFM-3Z) method was employed to analyze the combustion process. With crank positions at different EGR mass fractions, the exergy terms were identified and calculated separately. It was found that as EGR mass fraction increased from 0% to 30% (in 10% increment steps), exergy efficiency decreased from 48.9% to 28.7%. Furthermore, with the change in EGR mass fraction, the cumulative heat loss exergy decreased from 10.1% to 5.64% of mixture fuels chemical exergy.

  11. Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

    KAUST Repository

    Gasda, S. E.

    2009-04-23

    Large-scale implementation of geological CO2 sequestration requires quantification of risk and leakage potential. One potentially important leakage pathway for the injected CO2 involves existing oil and gas wells. Wells are particularly important in North America, where more than a century of drilling has created millions of oil and gas wells. Models of CO 2 injection and leakage will involve large uncertainties in parameters associated with wells, and therefore a probabilistic framework is required. These models must be able to capture both the large-scale CO 2 plume associated with the injection and the small-scale leakage problem associated with localized flow along wells. Within a typical simulation domain, many hundreds of wells may exist. One effective modeling strategy combines both numerical and analytical models with a specific set of simplifying assumptions to produce an efficient numerical-analytical hybrid model. The model solves a set of governing equations derived by vertical averaging with assumptions of a macroscopic sharp interface and vertical equilibrium. These equations are solved numerically on a relatively coarse grid, with an analytical model embedded to solve for wellbore flow occurring at the sub-gridblock scale. This vertical equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid refinement for sub-scale features. Through a series of benchmark problems, we show that VESA compares well with traditional numerical simulations and to a semi-analytical model which applies to appropriately simple systems. We believe that the VESA model provides the necessary accuracy and efficiency for applications of risk analysis in many CO2 sequestration problems. © 2009 Springer Science+Business Media B.V.

  12. SESAM: a model for the calculation of radiation exposure by emission of pollutants with the exhaust air in the case of a multi-source situation

    International Nuclear Information System (INIS)

    Ehrlich, H.G.; Vogt, K.J.; Brunen, E.

    The report deals with the calculation of the individual radiation exposure in the catchment area of several nuclear emitters. A model and computer program, SESAM - Calculation of the Radiation Exposure by Emission of Pollutants with the Exhaust air in the Case of a Multi-Source Situation -, was developed which makes possible all the evaluations of long-time exposure which are relevant for the licensing process - such as the determination of the maximum individual radiation exposure to the various organs at the worst receiving point - together with the exposure of the environment by several nuclear emission sources - such as, for example, several units of a power plant facility, the various emitters of a waste management center, or even consideration of the previous exposure of a site by nuclear emission sources

  13. SPE5 Sub-Scale Test Series Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Vandersall, Kevin S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reeves, Robert V. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); DeHaven, Martin R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Strickland, Shawn L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-01-14

    A series of 2 SPE5 sub-scale tests were performed to experimentally confirm that a booster system designed and evaluated in prior tests would properly initiate the PBXN-110 case charge fill. To conduct the experiments, a canister was designed to contain the nominally 50 mm diameter booster tube with an outer fill of approximately 150 mm diameter by 150 mm in length. The canisters were filled with PBXN-110 at NAWS-China Lake and shipped back to LLNL for testing in the High Explosives Applications Facility (HEAF). Piezoelectric crystal pins were placed on the outside of the booster tube before filling, and a series of piezoelectric crystal pins along with Photonic Doppler Velocimetry (PDV) probes were placed on the outer surface of the canister to measure the relative timing and magnitude of the detonation. The 2 piezoelectric crystal pins integral to the booster design were also utilized along with a series of either piezoelectric crystal pins or piezoelectric polymer pads on the top of the canister or outside case that utilized direct contact, gaps, or different thicknesses of RTV cushions to obtain time of arrival data to evaluate the response in preparation for the large-scale SPE5 test. To further quantify the margin of the booster operation, the 1st test (SPE5SS1) was functioned with both detonators and the 2nd test (SPE5SS2) was functioned with only 1 detonator. A full detonation of the material was observed in both experiments as observed by the pin timing and PDV signals. The piezoelectric pads were found to provide a greater measured signal magnitude during the testing with an RTV layer present, and the improved response is due to the larger measurement surface area of the pad. This report will detail the experiment design, canister assembly for filling, final assembly, experiment firing, presentation of the diagnostic results, and a discussion of the results.

  14. The genetic and environmental structure of the character sub-scales of the temperament and character inventory in adolescence.

    Science.gov (United States)

    Lester, Nigel; Garcia, Danilo; Lundström, Sebastian; Brändström, Sven; Råstam, Maria; Kerekes, Nóra; Nilsson, Thomas; Cloninger, C Robert; Anckarsäter, Henrik

    2016-01-01

    The character higher order scales (self-directedness, cooperativeness, and self-transcendence) in the temperament and character inventory are important general measures of health and well-being [Mens Sana Monograph 11:16-24 (2013)]. Recent research has found suggestive evidence of common environmental influence on the development of these character traits during adolescence. The present article expands earlier research by focusing on the internal consistency and the etiology of traits measured by the lower order sub-scales of the character traits in adolescence. The twin modeling analysis of 423 monozygotic pairs and 408 same sex dizygotic pairs estimated additive genetics (A), common environmental (C), and non-shared environmental (E) influences on twin resemblance. All twins were part of the on-going longitudinal Child and Adolescent Twin Study in Sweden (CATSS). The twin modeling analysis suggested a common environmental contribution for two out of five self-directedness sub-scales (0.14 and 0.23), for three out of five cooperativeness sub-scales (0.07-0.17), and for all three self-transcendence sub-scales (0.10-0.12). The genetic structure at the level of the character lower order sub-scales in adolescents shows that the proportion of the shared environmental component varies in the trait of self-directedness and in the trait of cooperativeness, while it is relatively stable across the components of self-transcendence. The presence of this unique shared environmental effect in adolescence has implications for understanding the relative importance of interventions and treatment strategies aimed at promoting overall maturation of character, mental health, and well-being during this period of the life span.

  15. Selective gas exhaustion method

    International Nuclear Information System (INIS)

    Hirano, Yoichi

    1998-01-01

    The present invention provides a method capable of evacuating gases at an exhaustion rate which varies depending on the kind of gases. For example, in a thermonuclear experimental device, a hydrogen gas exhaustion rate is determined to 0 and an exhaustion rate for other impure gases is made greater. Namely, a baffle plate is cooled to a temperature to a level at which the vapor pressure of gases to evacuate a baffle plate is required in a pump incorporating a baffle plate, for example, a cryopump or a sorption pump. In this case, the level of the vapor pressure required for evacuating the exhaustion gas ingredients is 1 x 10 -8 Torr or less, preferably, 1 x 10 -9 Torr. In a thermonuclear experimental device, a gas having a lower boiling point next to hydrogen is neon, but neon is scarcely present in natural world. Nitrogen has a lower boiling point next thereto, and if the temperature is lowered to such a level that the vapor pressure for evacuating gases such as nitrogen, and carbon monoxide, oxygen, fluorine, argon or methane having a boiling point at or lower than nitrogen is required. Then, evacuation rate sufficient for gases other than hydrogen gas can be obtained. (I.S.)

  16. Aerodynamic Control of Exhaust

    DEFF Research Database (Denmark)

    Hyldgård, Carl-Erik

    In the autumn of 1985 the Unive!Sity of Aalborg was approached by the manufacturer C. P. Aaberg, who had obtained aerodynilmic control of the exhaust by means of injection. The remaining investigations comprising optimizations of the system with regard to effect, consumption, requirements...

  17. Exhaust bypass flow control for exhaust heat recovery

    Science.gov (United States)

    Reynolds, Michael G.

    2015-09-22

    An exhaust system for an engine comprises an exhaust heat recovery apparatus configured to receive exhaust gas from the engine and comprises a first flow passage in fluid communication with the exhaust gas and a second flow passage in fluid communication with the exhaust gas. A heat exchanger/energy recovery unit is disposed in the second flow passage and has a working fluid circulating therethrough for exchange of heat from the exhaust gas to the working fluid. A control valve is disposed downstream of the first and the second flow passages in a low temperature region of the exhaust heat recovery apparatus to direct exhaust gas through the first flow passage or the second flow passage.

  18. Development of a modal emissions model using data from the Cooperative Industry/Government Exhaust Emission test program

    Science.gov (United States)

    2003-06-22

    The Environmental Protection Agencys (EPAs) recommended model, MOBILE5a, has been : used extensively to predict emission factors based on average speeds for each fleet type. : Because average speeds are not appropriate in modeling intersections...

  19. Impact of aircraft exhaust on the atmosphere. Box model studies and 3-D mesoscale numerical case studies of seasonal differences

    Energy Technology Data Exchange (ETDEWEB)

    Petry, H; Ebel, A; Franzkowiak, V; Hendricks, J; Lippert, E; Moellhoff, M [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie

    1998-12-31

    The impact of aircraft emissions released in the tropopause region on atmospheric trace gases as O{sub 3} or HNO{sub 3} is investigated by means of model studies. Special emphasis is drawn on seasonal effects. A box model is applied as well as a 3-D mesoscale chemistry transport model. These model studies show that the impact of aircraft emissions on ozone in the tropopause region is much stronger in summer than in late autumn with a difference of one order of magnitude. (author) 14 refs.

  20. Impact of aircraft exhaust on the atmosphere. Box model studies and 3-D mesoscale numerical case studies of seasonal differences

    Energy Technology Data Exchange (ETDEWEB)

    Petry, H.; Ebel, A.; Franzkowiak, V.; Hendricks, J.; Lippert, E.; Moellhoff, M. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie

    1997-12-31

    The impact of aircraft emissions released in the tropopause region on atmospheric trace gases as O{sub 3} or HNO{sub 3} is investigated by means of model studies. Special emphasis is drawn on seasonal effects. A box model is applied as well as a 3-D mesoscale chemistry transport model. These model studies show that the impact of aircraft emissions on ozone in the tropopause region is much stronger in summer than in late autumn with a difference of one order of magnitude. (author) 14 refs.

  1. Simplified CFD model of coolant channels typical of a plate-type fuel element: an exhaustive verification of the simulations

    Energy Technology Data Exchange (ETDEWEB)

    Mantecón, Javier González; Mattar Neto, Miguel, E-mail: javier.mantecon@ipen.br, E-mail: mmattar@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    The use of parallel plate-type fuel assemblies is common in nuclear research reactors. One of the main problems of this fuel element configuration is the hydraulic instability of the plates caused by the high flow velocities. The current work is focused on the hydrodynamic characterization of coolant channels typical of a flat-plate fuel element, using a numerical model developed with the commercial code ANSYS CFX. Numerical results are compared to accurate analytical solutions, considering two turbulence models and three different fluid meshes. For this study, the results demonstrated that the most suitable turbulence model is the k-ε model. The discretization error is estimated using the Grid Convergence Index method. Despite its simplicity, this model generates precise flow predictions. (author)

  2. Simplified CFD model of coolant channels typical of a plate-type fuel element: an exhaustive verification of the simulations

    International Nuclear Information System (INIS)

    Mantecón, Javier González; Mattar Neto, Miguel

    2017-01-01

    The use of parallel plate-type fuel assemblies is common in nuclear research reactors. One of the main problems of this fuel element configuration is the hydraulic instability of the plates caused by the high flow velocities. The current work is focused on the hydrodynamic characterization of coolant channels typical of a flat-plate fuel element, using a numerical model developed with the commercial code ANSYS CFX. Numerical results are compared to accurate analytical solutions, considering two turbulence models and three different fluid meshes. For this study, the results demonstrated that the most suitable turbulence model is the k-ε model. The discretization error is estimated using the Grid Convergence Index method. Despite its simplicity, this model generates precise flow predictions. (author)

  3. Real-time prediction of extreme ambient carbon monoxide concentrations due to vehicular exhaust emissions using univariate linear stochastic models

    International Nuclear Information System (INIS)

    Sharma, P.; Khare, M.

    2000-01-01

    Historical data of the time-series of carbon monoxide (CO) concentration was analysed using Box-Jenkins modelling approach. Univariate Linear Stochastic Models (ULSMs) were developed to examine the degree of prediction possible for situations where only a limited data set, restricted only to the past record of pollutant data are available. The developed models can be used to provide short-term, real-time forecast of extreme CO concentrations for an Air Quality Control Region (AQCR), comprising a major traffic intersection in a Central Business District of Delhi City, India. (author)

  4. The effect of Web-based Braden Scale training on the reliability of Braden subscale ratings.

    Science.gov (United States)

    Magnan, Morris A; Maklebust, JoAnn

    2009-01-01

    The primary purpose of this study was to evaluate the effect of Web-based Braden Scale training on the reliability of Braden Scale subscale ratings made by nurses working in acute care hospitals. A secondary purpose was to describe the distribution of reliable Braden subscale ratings before and after Web-based Braden Scale training. Secondary analysis of data from a recently completed quasi-experimental, pretest-posttest, interrater reliability study. A convenience sample of RNs working at 3 Michigan medical centers voluntarily participated in the study. RN participants included nurses who used the Braden Scale regularly at their place of employment ("regular users") as well as nurses who did not use the Braden Scale at their place of employment ("new users"). Using a pretest-posttest, quasi-experimental design, pretest interrater reliability data were collected to identify the percentage of nurses making reliable Braden subscale assessments. Nurses then completed a Web-based Braden Scale training module after which posttest interrater reliability data were collected. The reliability of nurses' Braden subscale ratings was determined by examining the level of agreement/disagreement between ratings made by an RN and an "expert" rating the same patient. In total, 381 RN-to-expert dyads were available for analysis. During both the pretest and posttest periods, the percentage of reliable subscale ratings was highest for the activity subscale, lowest for the moisture subscale, and second lowest for the nutrition subscale. With Web-based Braden Scale training, the percentage of reliable Braden subscale ratings made by new users increased for all 6 subscales with statistically significant improvements in the percentage of reliable assessments made on 3 subscales: sensory-perception, moisture, and mobility. Training had virtually no effect on the percentage of reliable subscale ratings made by regular users of the Braden Scale. With Web-based Braden Scale training the

  5. Three-dimensional approach to exhaust gas energy analysis

    Science.gov (United States)

    Sekavčnik, M.; Ogorevc, T.; Katrašnik, T.; Rodman-Oprešnik, S.

    2012-06-01

    Presented work is based on an extensive CFD simulation of the exhaust stroke of a single-cylinder four-stroke internal combustion engine with the exhaust manifold attached. Since the dynamics of the exhaust flow are extremely 3D, an innovative approach to calculate the local entropy generation is developed and implemented in the discussed 3D numerical model. It allows temporal and spatial determination of critical regions and periods of entropy generation in the process with objective to reduce it.

  6. Design and Evaluation of a Turbojet Exhaust Simulator, Utilizing a Solid-Propellant Rocket Motor, for use in Free-Flight Aerodynamic Research Models

    Science.gov (United States)

    deMoraes, Carlos A.; Hagginbothom, William K., Jr.; Falanga, Ralph A.

    1954-01-01

    A method has been developed for modifying a rocket motor so that its exhaust characteristics simulate those of a turbojet engine. The analysis necessary to the design is presented along with tests from which the designs are evaluated. Simulation was found to be best if the exhaust characteristics to be duplicated were those of a turbojet engine at high altitudes and with the afterburner operative.

  7. The Relationship Between Pathological Gambling and Sensation Seeking: The Role of Subscale Scores

    Science.gov (United States)

    Fortune, Erica E.

    2010-01-01

    Research investigating the relationship between gambling and sensation seeking has yet to establish conclusively whether pathological gamblers (PGs) are more or less sensation seeking than nonpathological gamblers (NPGs). Sensation seeking is usually measured with the Zuckerman et al. (J Consult Clin Psychol 46:139–149, 1978) SS Scale form V (SSS-V). Whereas previous studies relied on the SSS-V total score, the current study uses two samples to demonstrate the importance of the SSS-V subscales, which include Thrill and Adventure Seeking (TA), Experience Seeking (ES), Disinhibition (DS), and Boredom Susceptibility (BS). In two samples, strong intrascale correlations between DS and BS, and between TA and ES, suggest that certain subscales reflect similar underlying characteristics. In both samples PGs displayed higher scores than NPGs on the DS and BS subscales, with mean differences in Sample 2 reaching significant levels for both DS and BS. Results support the notion that the SSS-V can be divided into concepts reflecting actual behavior, based on the DS and BS subscales, and hypothetical behavior, based on the TA and ES subscales. Furthermore, PGs appear to have a preference for the more behavioral subscales while NPGs show a preference for the more hypothetical subscales. Reasons for the subscale divisions and preferences are discussed. PMID:19943092

  8. Improved spectral absorption coefficient grouping strategy of wide band k-distribution model used for calculation of infrared remote sensing signal of hot exhaust systems

    Science.gov (United States)

    Hu, Haiyang; Wang, Qiang

    2018-07-01

    A new strategy for grouping spectral absorption coefficients, considering the influences of both temperature and species mole ratio inhomogeneities on correlated-k characteristics of the spectra of gas mixtures, has been deduced to match the calculation method of spectral overlap parameter used in multiscale multigroup wide band k-distribution model. By comparison with current spectral absorption coefficient grouping strategies, for which only the influence of temperature inhomogeneity on the correlated-k characteristics of spectra of single species was considered, the improvements in calculation accuracies resulting from the new grouping strategy were evaluated using a series of 0D cases in which radiance under 3-5-μm wave band emitted by hot combustion gas of hydrocarbon fuel was attenuated by atmosphere with quite different temperature and mole ratios of water vapor and carbon monoxide to carbon dioxide. Finally, evaluations are presented on the calculation of remote sensing thermal images of transonic hot jet exhausted from a chevron ejecting nozzle with solid wall cooling system.

  9. Advanced exhaust nozzle technology

    Energy Technology Data Exchange (ETDEWEB)

    Glidewell, R J; Warburton, R E

    1981-01-01

    Recent developments in turbine engine exhaust nozzle technology include nonaxisymmetric nozzles, thrust reversing, and thrust vectoring. Trade studies have been performed to determine the impact of these developments on the thrust-to-weight ratio and specific fuel consumption of an advanced high performance, augmented turbofan engine. Results are presented in a manner which provides an understanding of the sources and magnitudes of differences in the basic elements of nozzle internal performance and weight as they relate to conventional, axisymmetric nozzle technology. Conclusions are presented and recommendations are made with regard to future directions of advanced development and demonstration. 5 refs.

  10. Catalytic exhaust control

    Energy Technology Data Exchange (ETDEWEB)

    Heinemann, H

    1973-09-01

    Recent achievements and problems in the development of exhaust control devices in the USA are reviewed. To meet the 1976 emission standards, catalytic systems for the oxidation of carbon monoxide and hydrocarbons and for the reduction of nitrogen oxides to nitrogen and water are needed. While oxidizing catalysts using platinum, palladium, copper, vanadium, and chromium appplied on alumina or ceramic materials are more or less effective in emission control, there are no catalytic devices for the reduction of nitrogen oxides with the required useful life of 25,000 to 50,000 miles as yet available. In the case of platinum catalysts on monolithic supports, the operating temperature of 650 to 750/sup 0/C as required for the oxidation process may cause inactivation of the catalysts and fusion of the support material. The oxidation of CO and hydrocarbons is inhibited by high concentrations of CO, nitric oxide, and hydrocarbons. The use of catalytic converters requires the use of lead-free or low-lead gasoline. The nitrogen oxides conversion efficiency is considerably influenced by the oxygen-to-CO ratio of the exhaust gas, which makes limitation of this ratio necessary.

  11. Measurement of pollutant species in automotive exhaust: application of a 3D Eulerian model about the photochemical oxidant formation in the troposphere

    International Nuclear Information System (INIS)

    Caplain, I.

    2005-05-01

    Automotive pollution has become a more and more worrying problem. Pollution regulations are more severe today but even if some pollutants have to fulfill strict emission standards, other compounds like volatile organic compounds (VOCs) and carbonyl compounds, are less controlled but remain toxic for human beings in a direct way (primary pollution) or in an indirect way (secondary pollution). This work deals with the experimental measurements of exhaust pollution, the inventory of pollutant emissions from transports, and the modeling of air quality. The experimental measurements are performed in the framework of the European project Artemis (assessment and reliability of transport emission models and inventory systems) under the coordination of INRETS, on a set of 30 gasoline and diesel vehicles of recent technology. These vehicles are submitted to various road tests in order to improve the emissions database for private vehicles. The main pollutants measured are the light VOCs (C2 to C6), the heavy VOCs (C7 to C15) and the carbonyl compounds. About a hundred of compounds are thus measured. The emissions factor of each pollutant has been determined for each vehicle and has been used for the elaboration of an emission map of the Nord-Pas-de-Calais region. These pollutant data have been used as input data for a physicochemical simulation model of troposphere (UAM: urban air-shed model). A previous study about the introduction of the detailed molecular speciation of VOCs and the use of the CBIV mechanism did not lead to concluding results about the speciation impact on ozone formation. The introduction of a new mechanism would allow to take into account the overall compounds and to see their eventual contribution to the ozone formation. This would require a modification of the model and in particular the addition of a flexible chemical mechanism (FCM) interface for the introduction of a new chemical mechanism (SAPRC 99 instead of CBIV) in the model. The overall input

  12. Exhaust pressure pulsation observation from turbocharger instantaneous speed measurement

    Science.gov (United States)

    Macián, V.; Luján, J. M.; Bermúdez, V.; Guardiola, C.

    2004-06-01

    In internal combustion engines, instantaneous exhaust pressure measurements are difficult to perform in a production environment. The high temperature of the exhaust manifold and its pulsating character make its application to exhaust gas recirculation control algorithms impossible. In this paper an alternative method for estimating the exhaust pressure pulsation is presented. A numerical model is built which enables the exhaust pressure pulses to be predicted from instantaneous turbocharger speed measurements. Although the model is data based, a theoretical description of the process is also provided. This combined approach makes it possible to export the model for different engine operating points. Also, compressor contribution in the turbocharger speed pulsation is discussed extensively. The compressor contribution is initially neglected, and effects of this simplified approach are analysed.

  13. Effects of exhaust temperature on helicopter infrared signature

    International Nuclear Information System (INIS)

    Cheng-xiong, Pan; Jing-zhou, Zhang; Yong, Shan

    2013-01-01

    The effects of exhaust temperature on infrared signature (in 3–5 μm band) for a helicopter equipped with integrative infrared suppressor were numerically investigated. The internal flow of exhaust gas and the external downwash flow, as well as the mixing between exhaust gas and downwash were simulated by CFD software to determine the temperature distributions on the helicopter skin and in the exhaust plume. Based on the skin and plume temperature distributions, a forward–backward ray-tracing method was used to calculate the infrared radiation intensity from the helicopter with a narrow-band model. The results show that for a helicopter with its integrative infrared suppressor embedded inside its rear airframe, the exhaust temperature has significant influence on the plume radiation characteristics, while the helicopter skin radiation intensity has little impact. When the exhaust temperature is raised from 900 K to 1200 K, the plume radiation intensity in 3–5 μm band is increased by about 100%, while the skin radiation intensity is increased by only about 5%. In general, the effects of exhaust temperature on helicopter infrared radiation intensity are mainly concentrated on plume, especially obvious for a lower skin emissivity case. -- Highlights: ► The effect of exhaust temperature on infrared signature for a helicopter is numerically investigated. ► The impact of exhaust temperature on helicopter skin temperature is revealed. ► The impact of exhaust temperature on plume radiation characteristics is revealed. ► The impact of exhaust temperature on helicopter skin radiation is revealed. ► The impact of exhaust temperature on helicopter's total infrared radiation intensity is revealed

  14. Airspace Simulation Through Indoor Operation of Subscale Flight Vehicles, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — An indoor environment for simulating airspace operations will be designed. Highly maneuverable subscale vehicles can be used to simulate the dynamics of full-scale...

  15. Sub-Scale Re-entry Capsule Drop via High Altitude Balloons

    Data.gov (United States)

    National Aeronautics and Space Administration — The project objective is to develop and test a sub-scale version of the Maraia Entry Capsule on a high altitude balloon. The capsule is released at 100,000 ft. The...

  16. Vertical equilibrium with sub-scale analytical methods for geological CO2 sequestration

    KAUST Repository

    Gasda, S. E.; Nordbotten, J. M.; Celia, M. A.

    2009-01-01

    equilibrium with sub-scale analytical method (VESA) combines the flexibility of a numerical method, allowing for heterogeneous and geologically complex systems, with the efficiency and accuracy of an analytical method, thereby eliminating expensive grid

  17. Planetary Airplane Extraction System Development and Subscale Testing

    Science.gov (United States)

    Teter, John E., Jr.

    2006-01-01

    The Aerial Regional-scale Environmental Survey (ARES) project will employ an airplane as the science platform from which to collect science data in the previously inaccessible, thin atmosphere of Mars. In order for the airplane to arrive safely in the Martian atmosphere, a number of sequences must occur. A critical element in the entry sequence at Mars is an extraction maneuver to separate the airplane quickly (in less than a second) from its protective backshell to reduce the possibility of re-contact, potentially leading to mission failure. This paper describes the development, testing, and lessons learned from building a 1/3 scale model of this airplane extraction system. This design, based on the successful Mars Exploration Rover (MER) extraction mechanism, employs a series of trucks rolling along tracks located on the surface of the central parachute can. Numerous tests using high speed video were conducted at the Langley Research Center to validate this concept. One area of concern was that that although the airplane released cleanly, a pitching moment could be introduced. While targeted for a Mars mission, this concept will enable environmental surveys by aircraft in other planetary bodies with a sensible atmosphere such as Venus or Saturn's moon, Titan.

  18. Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-Cog): Normative Data for the Portuguese Population.

    Science.gov (United States)

    Nogueira, Joana; Freitas, Sandra; Duro, Diana; Tábuas-Pereira, Miguel; Guerreiro, Manuela; Almeida, Jorge; Santana, Isabel

    2018-02-28

    The Alzheimer's Disease Assessment Scale - Cognitive Subscale is a brief battery developed to assess cognitive functioning in Alzheimer's disease that encompasses the core characteristics of cognitive decline (e.g. memory, language, praxis, constructive ability and orientation). The early detection, as well as the monitoring of cognitive decline along disease progression, is extremely important in clinical care and interventional research. The main goals of the present study were to analyze the psychometric properties of the Portuguese version of the Alzheimer's Disease Assessment Scale - Cognitive Subscale, and to establish normative values for the Portuguese population. The Portuguese version of Alzheimer's Disease Assessment Scale - Cognitive Subscale was administered to 223 cognitively healthy participants according to a standard assessment protocol consisting of the Mini-Mental State Examination, the Montreal Cognitive Assessment and the Adults and Older Adults Functional Assessment Inventory. Normal performance on the assessment protocol was the inclusion criteria for the study. The Alzheimer's Disease Assessment Scale - Cognitive Subscale revealed good psychometric properties when used in the Portuguese population. Age was the main predictor of the Alzheimer's Disease Assessment Scale - Cognitive Subscale total score (R2 = 0.123), whereas the influence of education level was lower (R2 = 0.027). These two variables explained 14.4% of the variance on the Alzheimer's Disease Assessment Scale - Cognitive Subscale scores and were used to stratify the normative values for the Portuguese population presented here. On the total sample, the average total score in the Alzheimer's Disease Assessment Scale - Cognitive Subscale was 6 points. The normative data were determined according to age and educational level as these were the sociodemographic variables that significantly contributed to the prediction of the Alzheimer's Disease Assessment Scale - Cognitive Subscale

  19. Evaluation of the Effect of Exhausts from Liquid and Solid Rockets on Ozone Layer

    Science.gov (United States)

    Yamagiwa, Yoshiki; Ishimaki, Tetsuya

    This paper reports the analytical results of the influences of solid rocket and liquid rocket exhausts on ozone layer. It is worried about that the exhausts from solid propellant rockets cause the ozone depletion in the ozone layer. Some researchers try to develop the analytical model of ozone depletion by rocket exhausts to understand its physical phenomena and to find the effective design of rocket to minimize its effect. However, these models do not include the exhausts from liquid rocket although there are many cases to use solid rocket boosters with a liquid rocket at the same time in practical situations. We constructed combined analytical model include the solid rocket exhausts and liquid rocket exhausts to analyze their effects. From the analytical results, we find that the exhausts from liquid rocket suppress the ozone depletion by solid rocket exhausts.

  20. Automotive Fuel and Exhaust Systems.

    Science.gov (United States)

    Irby, James F.; And Others

    Materials are provided for a 14-hour course designed to introduce the automotive mechanic to the basic operations of automotive fuel and exhaust systems incorporated on military vehicles. The four study units cover characteristics of fuels, gasoline fuel system, diesel fuel systems, and exhaust system. Each study unit begins with a general…

  1. Validation of Karolinska Exhaustion Scale: psychometric properties of a measure of exhaustion syndrome.

    Science.gov (United States)

    Saboonchi, Fredrik; Perski, Aleksander; Grossi, Giorgio

    2013-12-01

    The syndrome of exhaustion is currently a medical diagnosis in Sweden. The description of the syndrome largely corresponds to the suggested core component of burnout, that is exhaustion. Karolinska Exhaustion Scale (KES) has been constructed to provide specific assessment of exhaustion in clinical and research settings. The purpose of the present study was to examine the psychometric properties of this scale in its original and revised versions by examining the factorial structure and measures of convergent and discriminant validity. Data gathered from two independent samples (n1 = 358 & n2 = 403) consisting of patients diagnosed with 'reaction to severe stress, and adjustment disorder' were subjected to confirmatory factor analysis. The study's instruments were Karolinska Exhaustion Scale and Shirom Melam Burnout Measure. Correlation analyses were employed to follow up the established factorial structure of the scale. The study was ethically approved by Karolinska Institute regional ethic committee. The findings demonstrated adequate fit of the data to the measurement model provided by the revised version of KES Limitations: The main limitation of the present study is the lack of a gold standard of exhaustion for direct comparison with KES. (KES-26) and partially supported convergent validity and discriminant validity of the scale. The demonstrated psychometric properties of KES-26 indicate sound construct validity for this scale encouraging use of this scale in assessment of exhaustion. The factorial structure of KES-26 may also be used to provide information concerning possible different clinical profiles. © 2012 The Authors Scandinavian Journal of Caring Sciences © 2012 Nordic College of Caring Science.

  2. Psychosocial work environment and emotional exhaustion among middle-aged employees

    Directory of Open Access Journals (Sweden)

    Saastamoinen Peppiina

    2011-04-01

    Full Text Available Abstract Background This study examined the associations of job control, organizational justice and bullying at the workplace with emotional exhaustion. This was done by adjusting firstly for age and occupational class, secondly physical work factors, thirdly mutually adjusting for the three psychosocial factors and fourthly adjusting for all studied variables simultaneously. Data were derived from the Helsinki Health Study baseline surveys conducted in 2001 and 2002, including 40-60-year-old employees of the City of Helsinki (n = 5819, response rate 66%. Exhaustion was measured with a six-item subscale from Maslach Burnout Inventory (MBI. Psychosocial factors included Karasek's job control, organizational justice and bullying at the workplace. Logistic regression analysis was used. Results Among women 23% and among men 20% reported symptoms of emotional exhaustion. Among women all psychosocial factors were associated with exhaustion when adjusted for age and occupational class as confounders. When physical work factors were additionally adjusted for, the associations slightly attenuated but remained. When psychosocial work factors were simultaneously adjusted for each other, their associations with exhaustion attenuated but remained. Among men all psychosocial factors were associated with exhaustion when adjusted for confounders only. When adjusted for physical work factors the associations slightly attenuated. When psychosocial factors were simultaneously adjusted for each other, associations of organizational justice and bullying with exhaustion attenuated but remained whereas job control lost its association. Conclusions Identifying risk factors for emotional exhaustion is vital for preventing subsequent processes leading to burnout. Psychosocial factors are likely to contribute to exhaustion among female as well as male employees. Thus management and occupational health care should devote more attention to the psychosocial work environment

  3. Effects of fuels, engine load and exhaust after-treatment on diesel engine SVOC emissions and development of SVOC profiles for receptor modeling

    Science.gov (United States)

    Huang, Lei; Bohac, Stanislav V.; Chernyak, Sergei M.; Batterman, Stuart A.

    2015-01-01

    Diesel exhaust emissions contain numerous semivolatile organic compounds (SVOCs) for which emission information is limited, especially for idling conditions, new fuels and the new after-treatment systems. This study investigates exhaust emissions of particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and sterane and hopane petroleum biomarkers from a heavy-duty (6.4 L) diesel engine at various loads (idle, 600 and 900 kPa BMEP), with three types of fuel (ultra-low sulfur diesel or ULSD, Swedish low aromatic diesel, and neat soybean biodiesel), and with and without a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF). Swedish diesel and biodiesel reduced emissions of PM2.5, Σ15PAHs, Σ11NPAHs, Σ5Hopanes and Σ6Steranes, and biodiesel resulted in the larger reductions. However, idling emissions increased for benzo[k]fluoranthene (Swedish diesel), 5-nitroacenaphthene (biodiesel) and PM2.5 (biodiesel), a significant result given the attention to exposures from idling vehicles and the toxicity of high-molecular-weight PAHs and NPAHs. The DOC + DPF combination reduced PM2.5 and SVOC emissions during DPF loading (>99% reduction) and DPF regeneration (83–99%). The toxicity of diesel exhaust, in terms of the estimated carcinogenic risk, was greatly reduced using Swedish diesel, biodiesel fuels and the DOC + DPF. PAH profiles showed high abundances of three and four ring compounds as well as naphthalene; NPAH profiles were dominated by nitro-naphthalenes, 1-nitropyrene and 9-nitroanthracene. Both the emission rate and the composition of diesel exhaust depended strongly on fuel type, engine load and after-treatment system. The emissions data and chemical profiles presented are relevant to the development of emission inventories and exposure and risk assessments. PMID:25709535

  4. Effects of fuels, engine load and exhaust after-treatment on diesel engine SVOC emissions and development of SVOC profiles for receptor modeling.

    Science.gov (United States)

    Huang, Lei; Bohac, Stanislav V; Chernyak, Sergei M; Batterman, Stuart A

    2015-02-01

    Diesel exhaust emissions contain numerous semivolatile organic compounds (SVOCs) for which emission information is limited, especially for idling conditions, new fuels and the new after-treatment systems. This study investigates exhaust emissions of particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), nitro-PAHs (NPAHs), and sterane and hopane petroleum biomarkers from a heavy-duty (6.4 L) diesel engine at various loads (idle, 600 and 900 kPa BMEP), with three types of fuel (ultra-low sulfur diesel or ULSD, Swedish low aromatic diesel, and neat soybean biodiesel), and with and without a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF). Swedish diesel and biodiesel reduced emissions of PM 2.5 , Σ 15 PAHs, Σ 11 NPAHs, Σ 5 Hopanes and Σ 6 Steranes, and biodiesel resulted in the larger reductions. However, idling emissions increased for benzo[k]fluoranthene (Swedish diesel), 5-nitroacenaphthene (biodiesel) and PM 2.5 (biodiesel), a significant result given the attention to exposures from idling vehicles and the toxicity of high-molecular-weight PAHs and NPAHs. The DOC + DPF combination reduced PM 2.5 and SVOC emissions during DPF loading (>99% reduction) and DPF regeneration (83-99%). The toxicity of diesel exhaust, in terms of the estimated carcinogenic risk, was greatly reduced using Swedish diesel, biodiesel fuels and the DOC + DPF. PAH profiles showed high abundances of three and four ring compounds as well as naphthalene; NPAH profiles were dominated by nitro-naphthalenes, 1-nitropyrene and 9-nitroanthracene. Both the emission rate and the composition of diesel exhaust depended strongly on fuel type, engine load and after-treatment system. The emissions data and chemical profiles presented are relevant to the development of emission inventories and exposure and risk assessments.

  5. An Evaluation of the Texas Functional Living Scale's Latent Structure and Subscales.

    Science.gov (United States)

    González, David Andrés; Soble, Jason R; Marceaux, Janice C; McCoy, Karin J M

    2017-02-01

    Performance-based functional assessment is a critical component of neuropsychological practice. The Texas Functional Living Scale (TFLS) has promise given its brevity, nationally representative norms, and co-norming with Wechsler scales. However, its subscale structure has not been evaluated. The purpose of this study was to evaluate the TFLS in a mixed clinical sample (n = 197). Reliability and convergent and discriminant validity coefficients were calculated with neurocognitive testing and collateral reports and factor analysis was performed. The Money and Calculation subscale had the best psychometric properties of the subscales. The evidence did not support solitary interpretation of the Time subscale. A three-factor latent structure emerged representing memory and semantic retrieval, performance and visual scanning, and financial calculation. This study added psychometric support for interpretation of the TFLS total score and some of its subscales. Study limitations included sample characteristics (e.g., gender ratio) and low power for collateral report analyses. Published by Oxford University Press 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  6. Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

    Science.gov (United States)

    Lix, Lisa M; Wu, Xiuyun; Hopman, Wilma; Mayo, Nancy; Sajobi, Tolulope T; Liu, Juxin; Prior, Jerilynn C; Papaioannou, Alexandra; Josse, Robert G; Towheed, Tanveer E; Davison, K Shawn; Sawatzky, Richard

    2016-01-01

    Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36), can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF), which arises when population sub-groups with the same underlying (i.e., latent) level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF) and mental health (MH) sub-scale items in a Canadian population-based sample. Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos), which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC) method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health) produced estimates of the magnitude of DIF effects. The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size. SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

  7. Psychometric validation of the Hopkins Symptom Checklist (SCL-90) subscales for depression, anxiety, and interpersonal sensitivity

    DEFF Research Database (Denmark)

    Bech, P; Bille, J; Møller, S B

    2014-01-01

    BACKGROUND: The psychometric validity of many subscales of the 90-item Hopkins Symptom Checklist (SCL-90) remains largely unknown. Therefore, the aim of the present study was to evaluate the psychometric properties of the "Hamilton-subscales" for depression (SCL-D16), anxiety (SCL-A14), their 6......-item core-measures (SCL-D6 and SCL-A6), the anxiety symptom scale (SCL-ASS8) and the interpersonal sensitivity scale (IPS5). METHODS: The psychometric properties of the SCL-D16, SCL-A14, SCL-D6, SCL-A6, SCL-ASS8, and the IPS5 were evaluated based on SCL-90 ratings from 850 day patients from a Danish...... SCL-90 subscales were identified. Using these scales it is possible to perform a psychometrically valid evaluation of psychiatric patients regarding the severity of depression (HAM-D6), specific anxiety (SCL-ASS8) and interpersonal sensitivity (IPS5)....

  8. Device for purifying exhaust gas

    International Nuclear Information System (INIS)

    Makita, Kiyoshi.

    1973-01-01

    Purpose: To ensure the reliability in collection of krypton even on accident in liquidizing distillation tower. Constitution: Exhaust gas flows through active carbon adsorption tower where short half-life rare gas in exhaust gas is separated by adsorption, then through heat exchanger, then continuous distillation tower where krypton 85 is separated, then through batch distillation tower where krypton 85 is condensed, and then flows into storing cylinder. On accident in liquidizing distillation tower, at the first period exhaust gas flows through series connected active carbon adsorption tower, krypton 85 adsorbed in adsorption tower being transferred to cooling type adsorption tower, at the next period exhaust gas flows through tower, krypton 85 adsorbed in adsorption tower being transferred to tower. (M. K.)

  9. Subscales measuring symptoms of non-specific depression, anhedonia, and anxiety in the Edinburgh Postnatal Depression Scale.

    Science.gov (United States)

    Tuohy, Alan; McVey, Cynthia

    2008-06-01

    There has been considerable research and clinical interest in the comorbidity of anxiety and depression in the post-partum period, and specifically in the possibility that the commonly used Edinburgh Postnatal Depression Scale (EPDS) incorporates an anxiety component. We hypothesized that the recommended version of factor analysis (Fabrigar, Wegener, MacCallum, & Strahan, 1999) would identify such covert dimensions more reliably than the commonly used principal components analysis with varimax rotation and eigenvalues greater than 1. Principal axis factor extraction with parallel analysis and oblique (direct quartimin) factor rotation was applied to the 10 EPDS items. The study used a sample of recent mothers recruited and assessed via e-mail and the Internet (N=440). In addition to the EPDS, the Hospital Anxiety and Depression Scale (HADS) and the Positive and Negative Affect Scales (PANAS) were also administered. Three factors were found, which were identified as 'non-specific depressive symptoms', 'anhedonia', and 'anxietal symptoms' subscales, respectively. These subscales were regressed on the HADS anxiety and depression and the PANAS positive and negative affectivity scales, with results substantially consistent with current structural models of the taxonomy of the emotional disorders. The data were obtained from a self-selected non-clinical sample. In addition, it is known that the use of computer-based assessment may tend to inflate self-report scores. It was concluded that there is now sufficient evidence that clinicians should not assume the EPDS to be unidimensional, but should assess all three subscales when screening for susceptibility to post-partum depression and/or post-partum anxiety.

  10. Confirmatory Factor Analysis and Multiple Linear Regression of the Neck Disability Index: Assessment If Subscales Are Equally Relevant in Whiplash and Nonspecific Neck Pain.

    Science.gov (United States)

    Croft, Arthur C; Milam, Bryce; Meylor, Jade; Manning, Richard

    2016-06-01

    Because of previously published recommendations to modify the Neck Disability Index (NDI), we evaluated the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. The purpose of the present study was to evaluate the responsiveness and dimensionality of the NDI within a population of adult whiplash-injured subjects. Subjects who had sustained whiplash injuries of grade 2 or higher completed an NDI questionnaire. There were 123 subjects (55% female, of which 36% had recovered and 64% had chronic symptoms. NDI subscales were analyzed using confirmatory factor analysis, considering only the subscales and, secondly, using sex as an 11th variable. The subscales were also tested with multiple linear regression modeling using the total score as a target variable. When considering only the 10 NDI subscales, only a single factor emerged, with an eigenvalue of 5.4, explaining 53.7% of the total variance. Strong correlation (> .55) (P factor model of the NDI is not justified based on our results, and in this population of whiplash subjects, the NDI was unidimensional, demonstrating high internal consistency and supporting the original validation study of Vernon and Mior.

  11. Measurements of ion concentration in gasoline and diesel engine exhaust

    Science.gov (United States)

    Yu, Fangqun; Lanni, Thomas; Frank, Brian P.

    The nanoparticles formed in motor vehicle exhaust have received increasing attention due to their potential adverse health effects. It has been recently proposed that combustion-generated ions may play a critical role in the formation of these volatile nanoparticles. In this paper, we design an experiment to measure the total ion concentration in motor vehicle engine exhaust, and report some preliminary measurements in the exhaust of a gasoline engine (K-car) and a diesel engine (diesel generator). Under the experimental set-up reported in this study and for the specific engines used, the total ion concentration is ca. 3.3×10 6 cm -3 with almost all of the ions smaller than 3 nm in the gasoline engine exhaust, and is above 2.7×10 8 cm -3 with most of the ions larger than 3 nm in the diesel engine exhaust. This difference in the measured ion properties is interpreted as a result of the different residence times of exhaust inside the tailpipe/connecting pipe and the different concentrations of soot particles in the exhaust. The measured ion concentrations appear to be within the ranges predicted by a theoretical model describing the evolution of ions inside a pipe.

  12. 46 CFR 169.609 - Exhaust systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Exhaust systems. 169.609 Section 169.609 Shipping COAST... Electrical Internal Combustion Engine Installations § 169.609 Exhaust systems. Engine exhaust installations... Yacht Council, Inc. Standard P-1, “Safe Installation of Exhaust Systems for Propulsion and Auxiliary...

  13. 49 CFR 325.91 - Exhaust systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Exhaust systems. 325.91 Section 325.91... EMISSION STANDARDS Exhaust Systems and Tires § 325.91 Exhaust systems. Link to an amendment published at 75 FR 57193, Sept. 20, 2010. A motor vehicle does not conform to the visual exhaust system inspection...

  14. Subscale Carbon-Carbon Nozzle Extension Development and Hot Fire Testing in Support of Upper Stage Liquid Rocket Engines

    Science.gov (United States)

    Gradl, Paul; Valentine, Peter; Crisanti, Matthew; Greene, Sandy Elam

    2016-01-01

    Upper stage and in-space liquid rocket engines are optimized for performance through the use of high area ratio nozzles to fully expand combustion gases to low exit pressures increasing exhaust velocities. Due to the large size of such nozzles and the related engine performance requirements, carbon-carbon (C/C) composite nozzle extensions are being considered for use in order to reduce weight impacts. NASA and industry partner Carbon-Carbon Advanced Technologies (C-CAT) are working towards advancing the technology readiness level of large-scale, domestically-fabricated, C/C nozzle extensions. These C/C extensions have the ability to reduce the overall costs of extensions relative to heritage metallic and composite extensions and to decrease weight by 50%. Material process and coating developments have advanced over the last several years, but hot fire testing to fully evaluate C/C nozzle extensions in relevant environments has been very limited. NASA and C-CAT have designed, fabricated and hot fire tested multiple subscale nozzle extension test articles of various C/C material systems, with the goal of assessing and advancing the manufacturability of these domestically producible materials as well as characterizing their performance when subjected to the typical environments found in a variety of liquid rocket and scramjet engines. Testing at the MSFC Test Stand 115 evaluated heritage and state-of-the-art C/C materials and coatings, demonstrating the capabilities of the high temperature materials and their fabrication methods. This paper discusses the design and fabrication of the 1.2k-lbf sized carbon-carbon nozzle extensions, provides an overview of the test campaign, presents results of the hot fire testing, and discusses potential follow-on development work.

  15. Validity of the mental health subscale of the SF-36 in persons with spinal cord injury

    NARCIS (Netherlands)

    van Leeuwen, C. M. C.; van der Woude, L. H. V.; Post, M. W. M.

    Study design: Cross-sectional study 5 years after discharge from inpatient rehabilitation. Objective: To examine the psychometric properties of the Mental Health subscale (MHI-5) of the 36-Item Short Form Health Survey (SF-36) in persons with spinal cord injury (SCI). Setting: Eight Dutch

  16. Further Investigation of the SI Scale of the MMPI: Reliabilities, Correlates, and Subscale Utility.

    Science.gov (United States)

    Williams, Carolyn L.

    1983-01-01

    Administered the SI scale of the Minnesota Multiphasic Personality Inventory (MMPI) and several measures typically used in social skills and assertiveness training research to college students (N=218). Results demonstrated acceptable reliability and support for the utility of the subscales of the SI scale of the MMPI. (LLL)

  17. How well do the ADAS-cog and its subscales measure cognitive dysfunction in Alzheimer's disease?

    Science.gov (United States)

    Benge, Jared F; Balsis, Steve; Geraci, Lisa; Massman, Paul J; Doody, Rachelle S

    2009-01-01

    The Alzheimer's Disease Assessment Scale-cognitive (ADAS-cog) is regularly used to assess cognitive dysfunction in Alzheimer's disease (AD) clinical trials. Yet, little is known about how the instrument and its subscales measure cognition across the spectrum of AD. The current investigation used item response theory (IRT) analyses to assess the measurement properties of the ADAS-cog across the range of cognitive dysfunction in AD. We used IRT-based analyses to establish the relationship between cognitive dysfunction and the probability of obtaining observed scores on each subscale and the test as a whole. Data were obtained from 1,087 patients with AD and amnestic mild cognitive impairment. Results showed that the ADAS-cog and its subscales provide maximum information at moderate levels of cognitive dysfunction. Raw score differences toward the lower and higher ends of the scale corresponded to large differences in cognitive dysfunction, whereas raw score differences toward the middle of the scale corresponded to smaller differences. The utility of the ADAS-cog and its subscales is optimal in the moderate range of cognitive dysfunction, but raw score differences in that region correspond to relatively small differences in cognitive dysfunction. Implications for tracking and staging dementia and for clinical trials are discussed. Copyright 2009 S. Karger AG, Basel.

  18. Examining the Psychometric Properties of the Identify as a Professional Social Worker Subscale

    Science.gov (United States)

    Farmer, Antoinette Y.

    2017-01-01

    The purpose of this study was to examine the psychometric properties of the Identify as a Professional Social Worker Subscale, which assessed the Council on Social Work Education--prescribed competency "identify as a professional social worker and conduct oneself accordingly." The results of confirmatory factory analysis indicated that…

  19. Comparison of Child Behavior Checklist subscales in screening for obsessive-compulsive disorder

    DEFF Research Database (Denmark)

    Andersen, Pia Aaron Skovby; Bilenberg, Niels

    2012-01-01

    Obsessive-compulsive disorder (OCD) is a prevalent psychiatric disorder in children and adolescents associated with significant functional impairment. Early and correct diagnosis is essential for an optimal treatment outcome. The purpose of this study was to determine which of four subscales...... derived from the Child Behavior Checklist best discriminates OCD patients from clinical and population-based controls....

  20. Improving the utility of the fine motor skills subscale of the comprehensive developmental inventory for infants and toddlers: a computerized adaptive test.

    Science.gov (United States)

    Huang, Chien-Yu; Tung, Li-Chen; Chou, Yeh-Tai; Chou, Willy; Chen, Kuan-Lin; Hsieh, Ching-Lin

    2017-07-27

    This study aimed at improving the utility of the fine motor subscale of the comprehensive developmental inventory for infants and toddlers (CDIIT) by developing a computerized adaptive test of fine motor skills. We built an item bank for the computerized adaptive test of fine motor skills using the fine motor subscale of the CDIIT items fitting the Rasch model. We also examined the psychometric properties and efficiency of the computerized adaptive test of fine motor skills with simulated computerized adaptive tests. Data from 1742 children with suspected developmental delays were retrieved. The mean scores of the fine motor subscale of the CDIIT increased along with age groups (mean scores = 1.36-36.97). The computerized adaptive test of fine motor skills contains 31 items meeting the Rasch model's assumptions (infit mean square = 0.57-1.21, outfit mean square = 0.11-1.17). For children of 6-71 months, the computerized adaptive test of fine motor skills had high Rasch person reliability (average reliability >0.90), high concurrent validity (rs = 0.67-0.99), adequate to excellent diagnostic accuracy (area under receiver operating characteristic = 0.71-1.00), and large responsiveness (effect size = 1.05-3.93). The computerized adaptive test of fine motor skills used 48-84% fewer items than the fine motor subscale of the CDIIT. The computerized adaptive test of fine motor skills used fewer items for assessment but was as reliable and valid as the fine motor subscale of the CDIIT. Implications for Rehabilitation We developed a computerized adaptive test based on the comprehensive developmental inventory for infants and toddlers (CDIIT) for assessing fine motor skills. The computerized adaptive test has been shown to be efficient because it uses fewer items than the original measure and automatically presents the results right after the test is completed. The computerized adaptive test is as reliable and valid as the CDIIT.

  1. Development and validation of the functional assessment of cancer therapy-antiangiogenesis subscale.

    Science.gov (United States)

    Kaiser, Karen; Beaumont, Jennifer L; Webster, Kimberly; Yount, Susan E; Wagner, Lynne I; Kuzel, Timothy M; Cella, David

    2015-05-01

    The Functional Assessment of Cancer Therapy (FACT)-Antiangiogenesis (AntiA) Subscale was developed and validated to enhance treatment decision-making and side effect management for patients receiving anti-angiogenesis therapies. Side effects related to anti-angiogenesis therapies were identified from the literature, clinician input, and patient input. Fifty-nine possible patient expressions of side effects were generated. Patient and clinician ratings of the importance of these expressions led us to develop a 24-item questionnaire with clinical and research potential. To assess the scale's reliability and validity, 167 patients completed the AntiA Subscale, the Functional Assessment of Cancer Therapy-general (FACT-G), the FACT-Kidney Symptom Index (FKSI), the FACIT-Fatigue Subscale, the Global Rating of Change Scale (GRC), and the PROMIS Global Health Scale. Patient responses to the AntiA were analyzed for internal consistency, test-retest reliability, convergent and discriminant validity, and responsiveness to change in clinical status. All tested scales were found to have good internal consistency reliability (Cronbach's alpha 0.70-0.92). Test-retest reliability was also good (0.72-0.88) for total and subscale scores and lower for individual items. The total score, subscale scores, and all single items (except nosebleeds) significantly differentiated between groups defined by level of side effect bother. Evaluation of responsiveness to change in this study was not conclusive, suggesting an area for further research. The AntiA is a reliable and valid measure of side effects from anti-angiogenesis therapy. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  2. [Analysis of Possible Sociodemographic and Occupational Risk Factors and the Prevalence of Professional Exhaustion Syndrome (Burnout) in Mexican Dentists].

    Science.gov (United States)

    Castañeda Aguilera, Enrique; García de Alba García, Javier E

    2013-06-01

    To determine the prevalence of professional exhaustion syndrome (burnout) in dentists and to analyze possible sociodemographic and occupational risk factors . An observational, descriptive and cross-sectional survey of 203 dental staff of the Metropolitan Zone of Guadalajara, Mexico, from the Mexican Social Security Institute, University of Guadalajara, and those in private practice. A self-reported identification form and the Maslach Burnout Inventory-Human Services Survey were used to gather data. Descriptive statistics and inferential analyzes were performed using SPSS 15.0 support and EpiInfo V6.1. There was an 88.3% response. Professional exhaustion syndrome (burnout) was detected in 52.2% of them. Significant differences were obtained depending on the employment contract. A negative correlation was observed between the subscales emotional exhaustion and depersonalization, and a positive one between the lack of personal accomplishment at work. Professional exhaustion syndrome (burnout) is common (52.2%) for dentists, their possible risk factors: working in a public institution, being male, over 40 years, without a regular partner, and with more than 15 years with a partner, not having children, being a specialist with 10 years or more in an institution and the current job, morning shift, permanent recruitment, and having another job. The involvement of emotional exhaustion behaves like the syndrome. Average levels of the subscales are generally near normal. A negative correlation was found between the subscales emotional exhaustion and depersonalization, and positive between the lack of personal fulfillment at work with the presence of the syndrome. This leads us to consider the need for preventive measures in the workplace and personnel, as well as intervention programs at an individual, social or organizational level to reduce the prevalence found. Copyright © 2013 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  3. Effect of the temperature and dew point of the decarburization process on the oxide subscale of a 3% silicon steel

    Energy Technology Data Exchange (ETDEWEB)

    Cesar, Maria das Gracas M.M. E-mail: gracamelo@acesita.com.br; Mantel, Marc J

    2003-01-01

    The oxide subscale formed on the decarburization annealing of 3% Si-Fe was investigated using microscopy and spectroscopy techniques. It was found that the morphology as well as the molecular structure of the subscale are affected by temperature and dew point. The results suggest that there is an optimum level of internal oxidation and an optimum fayalite/silica ratio in the subscale to achieve a oriented grain silicon steel having a continuous and smooth ceramic film and low core loss.

  4. Semiconductor industry wafer fab exhaust management

    CERN Document Server

    Sherer, Michael J

    2005-01-01

    Given the myriad exhaust compounds and the corresponding problems that they can pose in an exhaust management system, the proper choice of such systems is a complex task. Presenting the fundamentals, technical details, and general solutions to real-world problems, Semiconductor Industry: Wafer Fab Exhaust Management offers practical guidance on selecting an appropriate system for a given application. Using examples that provide a clear understanding of the concepts discussed, Sherer covers facility layout, support facilities operations, and semiconductor process equipment, followed by exhaust types and challenges. He reviews exhaust point-of-use devices and exhaust line requirements needed between process equipment and the centralized exhaust system. The book includes information on wet scrubbers for a centralized acid exhaust system and a centralized ammonia exhaust system and on centralized equipment to control volatile organic compounds. It concludes with a chapter devoted to emergency releases and a separ...

  5. Ship exhaust gas plume cooling

    NARCIS (Netherlands)

    Schleijpen, H.M.A.; Neele, P.P.

    2004-01-01

    The exhaust gas plume is an important and sometimes dominating contributor to the infrared signature of ships. Suppression of the infrared ship signatures has been studied by TNO for the Royal Netherlands Navy over considerable time. This study deals with the suppression effects, which can be

  6. Numerical calculation on infrared characteristics of the special vehicle exhaust system

    Science.gov (United States)

    Feng, Yun-song; Li, Xiao-xia; Jin, Wei

    2017-10-01

    For mastery of infrared radiation characteristics and flow field of the special vehicle exhaust system, first, a physical model of the special vehicle exhaust system is established with the Gambit, and the mathematical model of flow field is determined. Secondly, software Fluent6.3 is used to simulated the 3-D exterior flow field of the special vehicle exhaust system, and the datum of flow field, such as temperature, pressure and density, are obtained. Thirdly, based on the plume temperature, the special vehicle exhaust space is divided. The exhaust is equivalent to a gray-body. A calculating model of the vehicle exhaust infrared radiation is established, and the exhaust infrared radiation characteristics are calculated by the software MATLAB, then the spatial distribution curves are drawn. Finally, the numerical results are analyzing, and the basic laws of the special vehicle exhaust infrared radiation are explored. The results show that with the increase of the engine speed, the temperature of the exhaust pipe wall of the special vehicle increases, and the temperature and pressure of the exhaust gas flow field increase, which leads to the enhancement of the infrared radiation intensity

  7. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development & Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan

    2014-01-01

    ATA-002 Technical Team has successfully designed, developed, tested and assessed the SLS Pathfinder propulsion systems for the Main Base Heating Test Program. Major Outcomes of the Pathfinder Test Program: Reach 90% of full-scale chamber pressure Achieved all engine/motor design parameter requirements Reach steady plume flow behavior in less than 35 msec Steady chamber pressure for 60 to 100 msec during engine/motor operation Similar model engine/motor performance to full-scale SLS system Mitigated nozzle throat and combustor thermal erosion Test data shows good agreement with numerical prediction codes Next phase of the ATA-002 Test Program Design & development of the SLS OML for the Main Base Heating Test Tweak BSRM design to optimize performance Tweak CS-REM design to increase robustness MSFC Aerosciences and CUBRC have the capability to develop sub-scale propulsion systems to meet desired performance requirements for short-duration testing.

  8. Diesel exhaust emissions : health effects

    Energy Technology Data Exchange (ETDEWEB)

    Grenier, M. [Natural Resources Canada, Sudbury, ON (Canada). CANMET Mining and Mineral Sciences Laboratories

    2009-07-01

    Despite modern day ventilation, underground miners are exposed to diesel particulate matter (DPM) composed of elemental carbon, organic carbon, sulphates, metals and ashes. Diesel exhaust contains over 40 air contaminants that have been recognized as toxic, carcinogenic or reproductive and developmental hazards. Nearly all components of diesel exhaust interact with the human body at the bloodstream or tissue level. This presentation discussed the following 4 potential levels of threat posed by the physical and chemical nature of diesel exhaust: (1) cancer of the lungs and bladder, (2) toxins that affect the nervous, endocrine, reproductive and immune system as well as the liver and kidneys, (3) fine particulate matter that can cause premature death and an increase in respiratory illness, and (4) nitrogen oxides that contribute to increased ozone and smog. Non-cancer health effects from short-term exposure include acute irritation and respiratory symptoms. This presentation also referred to cancer risk assessments of diesel exhaust by national, state, and world health organizations. Particulate exposure standards for Canada, Quebec, Ontario and the United States were listed along with the percentage of DPM samples in excess of various exposure limits in 2008 according to Canadian underground mine data. DPM concentration levels in mines are in the range that environmental agencies would consider high for general population exposure. Solutions for underground mines include pollution control at the source; use of modern engines with certification for underground mining; emissions based maintenance; exhaust treatment; use of clean or alternative fuels such as hydrogen; regular sampling and monitoring; ventilation; training and technology transfer; and regulations. tabs., figs.

  9. Simulation of exhaust gas heat recovery from a spray dryer

    International Nuclear Information System (INIS)

    Golman, Boris; Julklang, Wittaya

    2014-01-01

    This study explored various alternatives in improving the energy utilization of spray drying process through the exhaust gas heat recovery. Extensible and user-friendly simulation code was written in Visual Basic for Applications within Microsoft Excel for this purpose. The effects of process parameters were analyzed on the energy efficiency and energy saving in the industrial-scale spray drying system with exhaust gas heat recovery in an air-to-air heat exchanger and in the system with partial recirculation of exhaust air. The spray dryer is equipped with an indirect heater for heating the drying air. The maximum gains of 16% in energy efficiency and 50% in energy saving were obtained for spray drying system equipped with heat exchanger for exhaust air heat recovery. In addition, 34% in energy efficiency and 61% in energy saving for system with recirculation of exhaust air in the present range of process parameters. The high energy efficiency was obtained during drying of large amount of dilute slurry. The energy saving was increased using the large amount of hot drying air. - Highlights: • We model industrial-scale spray drying process with the exhaust gas heat recovery. • We develop an Excel VBA computer program to simulate spray dryer with heat recovery. • We examine effects of process parameters on energy efficiency and energy saving. • High energy efficiency is obtained during drying of large amount of dilute slurry. • Energy saving is increased using the large amount of hot drying air

  10. Model aerodynamic test results for two variable cycle engine coannular exhaust systems at simulated takeoff and cruise conditions. [Lewis 8 by 6-foot supersonic wind tunnel tests

    Science.gov (United States)

    Nelson, D. P.

    1980-01-01

    Wind tunnel tests were conducted to evaluate the aerodynamic performance of a coannular exhaust nozzle for a proposed variable stream control supersonic propulsion system. Tests were conducted with two simulated configurations differing primarily in the fan duct flowpaths: a short flap mechanism for fan stream control with an isentropic contoured flow splitter, and an iris fan nozzle with a conical flow splitter. Both designs feature a translating primary plug and an auxiliary inlet ejector. Tests were conducted at takeoff and simulated cruise conditions. Data were acquired at Mach numbers of 0, 0.36, 0.9, and 2.0 for a wide range of nozzle operating conditions. At simulated supersonic cruise, both configurations demonstrated good performance, comparable to levels assumed in earlier advanced supersonic propulsion studies. However, at subsonic cruise, both configurations exhibited performance that was 6 to 7.5 percent less than the study assumptions. At take off conditions, the iris configuration performance approached the assumed levels, while the short flap design was 4 to 6 percent less.

  11. Model aerodynamic test results for two variable cycle engine coannular exhaust systems at simulated takeoff and cruise conditions. Comprehensive data report. Volume 2: Tabulated aeroynamic data book 1

    Science.gov (United States)

    Nelson, D. P.

    1981-01-01

    Tabulated data from wind tunnel tests conducted to evaluate the aerodynamic performance of an advanced coannular exhaust nozzle for a future supersonic propulsion system are presented. Tests were conducted with two test configurations: (1) a short flap mechanism for fan stream control with an isentropic contoured flow splitter, and (2) an iris fan nozzle with a conical flow splitter. Both designs feature a translating primary plug and an auxiliary inlet ejector. Tests were conducted at takeoff and simulated cruise conditions. Data were acquired at Mach numbers of 0, 0.36, 0.9, and 2.0 for a wide range of nozzle operating conditions. At simulated supersonic cruise, both configurations demonstrated good performance, comparable to levels assumed in earlier advanced supersonic propulsion studies. However, at subsonic cruise, both configurations exhibited performance that was 6 to 7.5 percent less than the study assumptions. At takeoff conditions, the iris configuration performance approached the assumed levels, while the short flap design was 4 to 6 percent less. Data are provided through test run 25.

  12. Aircraft exhaust aerosol formation and growth

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R C; Miake-Lye, R C; Anderson, M R; Kolb, C E [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics

    1998-12-31

    Aerosol formation and growth in the exhaust plume of the ATTAS aircraft at an altitude of approximately 9 km, burning fuels with 2 ppmm sulfur (`low`) and 266 ppmm (`high`) sulfur has been modeled using an aerosol dynamics model for nucleation, vapor condensation and coagulation, coupled to a 2-dimensional, axisymmetric flow code to treat plume dilution and turbulent mixing. For both the `low` and `high` sulfur fuels, approximately 60% of the available water had condensed within the first 200 m downstream of the exhaust exit. The contrail particle diameters ranged between 0.4 to 1.6 {mu}m. However, the size distributions as a function of radial position for the `low` sulfur plume were broader than the corresponding distributions for the `high` sulfur plume. The model results indicate for a fuel sulfur mass loading of 2 ppmm, sulfuric acid remains a viable activating agent and that the differences in the contrail particle size distributions for sulfur mass loadings between 2 ppmm and 260 ppmm would be difficult to detect. (author) 12 refs.

  13. Aircraft exhaust aerosol formation and growth

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Miake-Lye, R.C.; Anderson, M.R.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics

    1997-12-31

    Aerosol formation and growth in the exhaust plume of the ATTAS aircraft at an altitude of approximately 9 km, burning fuels with 2 ppmm sulfur (`low`) and 266 ppmm (`high`) sulfur has been modeled using an aerosol dynamics model for nucleation, vapor condensation and coagulation, coupled to a 2-dimensional, axisymmetric flow code to treat plume dilution and turbulent mixing. For both the `low` and `high` sulfur fuels, approximately 60% of the available water had condensed within the first 200 m downstream of the exhaust exit. The contrail particle diameters ranged between 0.4 to 1.6 {mu}m. However, the size distributions as a function of radial position for the `low` sulfur plume were broader than the corresponding distributions for the `high` sulfur plume. The model results indicate for a fuel sulfur mass loading of 2 ppmm, sulfuric acid remains a viable activating agent and that the differences in the contrail particle size distributions for sulfur mass loadings between 2 ppmm and 260 ppmm would be difficult to detect. (author) 12 refs.

  14. 40 CFR 1065.130 - Engine exhaust.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Engine exhaust. 1065.130 Section 1065... ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.130 Engine exhaust. (a) General. Use the exhaust system installed with the engine or one that represents a typical in-use configuration. This...

  15. Subscales correlations between MSSS-88 and PRISM scales in evaluation of spasticity for patients with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Knežević Tatjana

    2017-01-01

    Full Text Available Introduction/Objective. Patient-reported outcomes have been recognized as an important way of assessing health and well-being of patients with multiple sclerosis (MS. The aim of the study is to determine the correlation between different subscales of Patient-Reported Impact of Spasticity Measure (PRISM and Multiple Sclerosis Spasticity Scale (MSSS-88 scales in the estimation of spasticity influence on different domains Methods. The study is a cross-sectional observational study. MSSS-88 and PRISM scales were analyzed in five domains (body-function domain, activity domain, participation domain, personal factors/wellbeing domain, and hypothesis. For statistical interpretation of the correlation we performed the Spearman’s ρ-test, concurrent validity, divergent validity, and the linear regression model. Results. We found a significant correlation between subscales of evaluated MSSS-88 and PRISM scales for body domains; the highest correlation was between the need for assistance/positioning (NA/P and walking (W. Spasticity has the weakest correlation with the need for intervention (NI. The presence of pain has a negative impact and significant positive correlation between pain discomfort and NI. In the domain of body function for males, there was a non-significant correlation between muscle spasms and NI. The same applies for social functioning and social embarrassment domains, as well as for emotional health and psychological agitation for personal factors / wellbeing domain. The differences between genders of MS patients persist in different domains; muscle spasms are strong predictors for NI, and body movement is a strong predictor versus W for NA/P. Conclusion. MSSS-88 and PRISM scales can be considered reliable in measuring different domains of disability for MS patients with spasticity. Because it is shorter, quicker, and simple to use, it is concluded that the PRISM scale can successfully compete with and replace the MSSS-88 scale in

  16. Differential Item Functioning in the SF-36 Physical Functioning and Mental Health Sub-Scales: A Population-Based Investigation in the Canadian Multicentre Osteoporosis Study.

    Directory of Open Access Journals (Sweden)

    Lisa M Lix

    Full Text Available Self-reported health status measures, like the Short Form 36-item Health Survey (SF-36, can provide rich information about the overall health of a population and its components, such as physical, mental, and social health. However, differential item functioning (DIF, which arises when population sub-groups with the same underlying (i.e., latent level of health have different measured item response probabilities, may compromise the comparability of these measures. The purpose of this study was to test for DIF on the SF-36 physical functioning (PF and mental health (MH sub-scale items in a Canadian population-based sample.Study data were from the prospective Canadian Multicentre Osteoporosis Study (CaMos, which collected baseline data in 1996-1997. DIF was tested using a multiple indicators multiple causes (MIMIC method. Confirmatory factor analysis defined the latent variable measurement model for the item responses and latent variable regression with demographic and health status covariates (i.e., sex, age group, body weight, self-perceived general health produced estimates of the magnitude of DIF effects.The CaMos cohort consisted of 9423 respondents; 69.4% were female and 51.7% were less than 65 years. Eight of 10 items on the PF sub-scale and four of five items on the MH sub-scale exhibited DIF. Large DIF effects were observed on PF sub-scale items about vigorous and moderate activities, lifting and carrying groceries, walking one block, and bathing or dressing. On the MH sub-scale items, all DIF effects were small or moderate in size.SF-36 PF and MH sub-scale scores were not comparable across population sub-groups defined by demographic and health status variables due to the effects of DIF, although the magnitude of this bias was not large for most items. We recommend testing and adjusting for DIF to ensure comparability of the SF-36 in population-based investigations.

  17. Simulation of Wake Vortex Radiometric Detection via Jet Exhaust Proxy

    Science.gov (United States)

    Daniels, Taumi S.

    2015-01-01

    This paper describes an analysis of the potential of an airborne hyperspectral imaging IR instrument to infer wake vortices via turbine jet exhaust as a proxy. The goal was to determine the requirements for an imaging spectrometer or radiometer to effectively detect the exhaust plume, and by inference, the location of the wake vortices. The effort examines the gas spectroscopy of the various major constituents of turbine jet exhaust and their contributions to the modeled detectable radiance. Initially, a theoretical analysis of wake vortex proxy detection by thermal radiation was realized in a series of simulations. The first stage used the SLAB plume model to simulate turbine jet exhaust plume characteristics, including exhaust gas transport dynamics and concentrations. The second stage used these plume characteristics as input to the Line By Line Radiative Transfer Model (LBLRTM) to simulate responses from both an imaging IR hyperspectral spectrometer or radiometer. These numerical simulations generated thermal imagery that was compared with previously reported wake vortex temperature data. This research is a continuation of an effort to specify the requirements for an imaging IR spectrometer or radiometer to make wake vortex measurements. Results of the two-stage simulation will be reported, including instrument specifications for wake vortex thermal detection. These results will be compared with previously reported results for IR imaging spectrometer performance.

  18. Subscales of the Barratt Impulsiveness Scale differentially relate to the Big Five factors of personality.

    Science.gov (United States)

    Lange, Florian; Wagner, Adina; Müller, Astrid; Eggert, Frank

    2017-06-01

    The place of impulsiveness in multidimensional personality frameworks is still unclear. In particular, no consensus has yet been reached with regard to the relation of impulsiveness to Neuroticism and Extraversion. We aim to contribute to a clearer understanding of these relationships by accounting for the multidimensional structure of impulsiveness. In three independent studies, we related the subscales of the Barratt Impulsiveness Scale (BIS) to the Big Five factors of personality. Study 1 investigated the associations between the BIS subscales and the Big Five factors as measured by the NEO Five-Factor Inventory (NEO-FFI) in a student sample (N = 113). Selective positive correlations emerged between motor impulsiveness and Extraversion and between attentional impulsiveness and Neuroticism. This pattern of results was replicated in Study 2 (N = 132) using a 10-item short version of the Big Five Inventory. In Study 3, we analyzed BIS and NEO-FFI data obtained from a sample of patients with pathological buying (N = 68). In these patients, the relationship between motor impulsiveness and Extraversion was significantly weakened when compared to the non-clinical samples. At the same time, the relationship between attentional impulsiveness and Neuroticism was substantially stronger in the clinical sample. Our studies highlight the utility of the BIS subscales for clarifying the relationship between impulsiveness and the Big Five personality factors. We conclude that impulsiveness might occupy multiple places in multidimensional personality frameworks, which need to be specified to improve the interpretability of impulsiveness scales. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  19. Using data from Multidimensional Pain Inventory subscales to assess functioning in pain rehabilitation

    DEFF Research Database (Denmark)

    Harlacher, Uwe; Persson, Ann L; Rivano-Fischer, Marcelo

    2011-01-01

    The aim of this study was to examine whether Multidimensional Pain Inventory (MPI) subscale score changes can be used for monitoring interdisciplinary cognitive behavioural pain rehabilitation programmes, using the Psychological General Well-Being (PGWB) index as an independent variable...... of rehabilitation outcome. Data from 434 consecutively referred patients disabled by chronic pain were analysed. The intervention was a 4-week interdisciplinary pain rehabilitation group programme (5 h/day), based on biopsychosocial and cognitive behavioural principles. Mean PGWB total scores improved after...... rehabilitation (P...

  20. Impaired vascular function after exposure to diesel exhaust generated at urban transient running conditions

    Directory of Open Access Journals (Sweden)

    Westerholm Roger

    2010-07-01

    Full Text Available Abstract Background Traffic emissions including diesel engine exhaust are associated with increased respiratory and cardiovascular morbidity and mortality. Controlled human exposure studies have demonstrated impaired vascular function after inhalation of exhaust generated by a diesel engine under idling conditions. Objectives To assess the vascular and fibrinolytic effects of exposure to diesel exhaust generated during urban-cycle running conditions that mimic ambient 'real-world' exposures. Methods In a randomised double-blind crossover study, eighteen healthy male volunteers were exposed to diesel exhaust (approximately 250 μg/m3 or filtered air for one hour during intermittent exercise. Diesel exhaust was generated during the urban part of the standardized European Transient Cycle. Six hours post-exposure, vascular vasomotor and fibrinolytic function was assessed during venous occlusion plethysmography with intra-arterial agonist infusions. Measurements and Main Results Forearm blood flow increased in a dose-dependent manner with both endothelial-dependent (acetylcholine and bradykinin and endothelial-independent (sodium nitroprusside and verapamil vasodilators. Diesel exhaust exposure attenuated the vasodilatation to acetylcholine (P Conclusion Exposure to diesel exhaust generated under transient running conditions, as a relevant model of urban air pollution, impairs vasomotor function and endogenous fibrinolysis in a similar way as exposure to diesel exhaust generated at idling. This indicates that adverse vascular effects of diesel exhaust inhalation occur over different running conditions with varying exhaust composition and concentrations as well as physicochemical particle properties. Importantly, exposure to diesel exhaust under ETC conditions was also associated with a novel finding of impaired of calcium channel-dependent vasomotor function. This implies that certain cardiovascular endpoints seem to be related to general diesel

  1. Space Launch System Base Heating Test: Sub-Scale Rocket Engine/Motor Design, Development and Performance Analysis

    Science.gov (United States)

    Mehta, Manish; Seaford, Mark; Kovarik, Brian; Dufrene, Aaron; Solly, Nathan; Kirchner, Robert; Engel, Carl D.

    2014-01-01

    The Space Launch System (SLS) base heating test is broken down into two test programs: (1) Pathfinder and (2) Main Test. The Pathfinder Test Program focuses on the design, development, hot-fire test and performance analyses of the 2% sub-scale SLS core-stage and booster element propulsion systems. The core-stage propulsion system is composed of four gaseous oxygen/hydrogen RS-25D model engines and the booster element is composed of two aluminum-based model solid rocket motors (SRMs). The first section of the paper discusses the motivation and test facility specifications for the test program. The second section briefly investigates the internal flow path of the design. The third section briefly shows the performance of the model RS-25D engines and SRMs for the conducted short duration hot-fire tests. Good agreement is observed based on design prediction analysis and test data. This program is a challenging research and development effort that has not been attempted in 40+ years for a NASA vehicle.

  2. Exposure assessment in studies on health effects of traffic exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Setaelae, S [Association for the Pulmonary Disabled, Helsinki (Finland); Jaakkola, J J.K. [Helsinki Univ. (Finland). Dept. of Public Health

    1996-12-31

    A main source of outdoor air pollution is road traffic, which produces a complex mixture of nitrogen oxides, carbon monoxide, volatile hydrocarbons, airborne particles and some other compounds. Traffic exhaust affects also the concentrations of ozone and other photo chemical oxidants. In earlier studies those components have had remarkable health effects. Several studies on occupational exposure to automobile exhaust have been published and several studies have been observed an association between both outdoor and indoor pollutant levels and health outcomes. However, there are only a few epidemiological studies in which traffic exhaust, a complex mixture, has been studied in its entirety. During recent years, interesting epidemiological studies of the health effects of this complex mixture have been published. Human exposure assessment for traffic exhaust can be categorized according to the environment of exposure (indoors, outdoors, in-traffic) or to the method of exposure assessment (direct or indirect methods). In this presentation the methods are further categorized into (1) traffic activity, (2) air concentration measurements, and (3) dispersion models, in order to better understand the advantages and disadvantages of different approaches. The objective of this presentation is to make a critical review of exposure assessments in the epidemiological studies on health effects of traffic exhaust. (author)

  3. Exposure assessment in studies on health effects of traffic exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Setaelae, S. [Association for the Pulmonary Disabled, Helsinki (Finland); Jaakkola, J.J.K. [Helsinki Univ. (Finland). Dept. of Public Health

    1995-12-31

    A main source of outdoor air pollution is road traffic, which produces a complex mixture of nitrogen oxides, carbon monoxide, volatile hydrocarbons, airborne particles and some other compounds. Traffic exhaust affects also the concentrations of ozone and other photo chemical oxidants. In earlier studies those components have had remarkable health effects. Several studies on occupational exposure to automobile exhaust have been published and several studies have been observed an association between both outdoor and indoor pollutant levels and health outcomes. However, there are only a few epidemiological studies in which traffic exhaust, a complex mixture, has been studied in its entirety. During recent years, interesting epidemiological studies of the health effects of this complex mixture have been published. Human exposure assessment for traffic exhaust can be categorized according to the environment of exposure (indoors, outdoors, in-traffic) or to the method of exposure assessment (direct or indirect methods). In this presentation the methods are further categorized into (1) traffic activity, (2) air concentration measurements, and (3) dispersion models, in order to better understand the advantages and disadvantages of different approaches. The objective of this presentation is to make a critical review of exposure assessments in the epidemiological studies on health effects of traffic exhaust. (author)

  4. Organic positive ions in aircraft gas-turbine engine exhaust

    Science.gov (United States)

    Sorokin, Andrey; Arnold, Frank

    Volatile organic compounds (VOCs) represent a significant fraction of atmospheric aerosol. However the role of organic species emitted by aircraft (as a consequence of the incomplete combustion of fuel in the engine) in nucleation of new volatile particles still remains rather speculative and requires a much more detailed analysis of the underlying mechanisms. Measurements in aircraft exhaust plumes have shown the presence of both different non-methane VOCs (e.g. PartEmis project) and numerous organic cluster ions (MPIK-Heidelberg). However the link between detected organic gas-phase species and measured mass spectrum of cluster ions is uncertain. Unfortunately, up to now there are no models describing the thermodynamics of the formation of primary organic cluster ions in the exhaust of aircraft engines. The aim of this work is to present first results of such a model development. The model includes the block of thermodynamic data based on proton affinities and gas basicities of organic molecules and the block of non-equilibrium kinetics of the cluster ions evolution in the exhaust. The model predicts important features of the measured spectrum of positive ions in the exhaust behind aircraft. It is shown that positive ions emitted by aircraft engines into the atmosphere mostly consist of protonated and hydrated organic cluster ions. The developed model may be explored also in aerosol investigations of the background atmosphere as well as in the analysis of the emission of fine aerosol particles by automobiles.

  5. Exhaust gas clean up process

    Science.gov (United States)

    Walker, R.J.

    1988-06-16

    A method of cleaning an exhaust gas containing particulates, SO/sub 2/ and NO/sub x/ is described. The method involves prescrubbing with water to remove HCl and most of the particulates, scrubbing with an aqueous absorbent containing a metal chelate and dissolved sulfite salt to remove NO/sub x/ and SO/sub 2/, and regenerating the absorbent solution by controlled heating, electrodialysis and carbonate salt addition. The NO/sub x/ is removed as N/sub 2/ gas or nitrogen sulfonate ions and the oxides of sulfur are removed as a valuable sulfate salt. 4 figs.

  6. Getting older can be exhausting.

    Science.gov (United States)

    Mittal, Rohit; Ford, Mandy L; Coopersmith, Craig M

    2014-07-29

    Sepsis is a disease that affects primarily the aged. Although mortality is higher in both older septic patients and aged septic mice, the mechanisms underlying decreased survival in older hosts are incompletely understood. New work by Inoue and colleagues demonstrates persistent inflammation and T-cell exhaustion in older septic patients and aged septic mice. The clinical significance of these findings is manifested not only in increased mortality but also in a marked difference in secondary infections in older patients as long as a month following ICU admission.

  7. Gas turbine exhaust system silencing design

    International Nuclear Information System (INIS)

    Ozgur, D.

    1991-01-01

    Gas turbines are the preferred prime mover in many applications because of their high efficiency, fuel flexibility, and low environmental impact. A typical mid-size machine might have a power rating of 80 MW, a flow of about 1000 kg/hr, and an exhaust temperature of over 500C. The most powerful single source of noise is generally the exhaust, which may generate over a kilowatt of acoustic energy. This paper reports that there are two important ways in which exhaust systems can radiate noise. The first is through the discharge of the exhaust duct, with the exhaust gas. Because of the large quantity of hot gas, the duct exit is always oriented vertically; it may be fairly high in the air in order to promote dispersion of the exhaust plume. This source is almost always attenuated by means of a silencer located somewhere in the ductwork. The second source of noise is often called breakout; it is the radiation of exhaust noise through the walls of the ducting. Breakout is most important for those sections of the exhaust duct which lie upstream of the silencer, where sound levels inside the ducting are highest. Both exhaust duct exit noise and breakout noise can be calculated from the sound power level of the gas turbine exhaust and the sound transmission loss (TL) of the silencer and ducting

  8. Change of International Restless Legs Syndrome Study Group Rating Scale subscales with treatment and placebo: a pilot study

    Directory of Open Access Journals (Sweden)

    Mitchell UH

    2014-02-01

    Full Text Available Ulrike H Mitchell,1 Sterling C Hilton2 1Brigham Young University, Department of Exercise Sciences, 2Department of Educational Leadership and Foundations, Provo, UT, USA Background: In 2003, the 10-question International Restless Legs Syndrome Study Group Rating Scale (IRLS was developed as a means of assessing the severity of restless legs syndrome. Two subscales were identified: symptom severity (SS 1 and symptom impact (SS 2. Only one study has investigated the subscales' responsiveness to a 12-week treatment with ropinirole. This current study was undertaken to assess the impact of a 4-week, non-pharmaceutical treatment on the two subscales and to explore whether or not both subscales were impacted by the observed placebo effect. Methods: The pooled data from questionnaires of 58 patients (41 from both treatment groups and 17 from the sham treatment control group, who participated in two clinical studies, were reviewed. Their change in score over a 4-week trial was computed. The average change in both subscales in both groups was computed and t-tests were performed. Results: In the treatment group, the average scores of both subscales changed significantly from baseline to week 4 (P<0.005 for both. Compared to the control, SS 1 changed (P<0.001, but not SS 2 (P=0.18. In the sham treatment group, the scores for SS 1 changed significantly (P=0.002, but not for SS 2 (P=0.2. Conclusion: This study corroborated findings from an earlier study in which both subscales changed with a 12-week drug treatment. It also showed that the observed placebo effect is attributed to a small but significant change in symptom severity, but not symptom impact. Keywords: restless legs syndrome, RLS severity scale, IRLS subscales, symptom impact, symptom severity

  9. Reliability and validity of a short version of the general functioning subscale of the McMaster Family Assessment Device.

    Science.gov (United States)

    Boterhoven de Haan, Katrina L; Hafekost, Jennifer; Lawrence, David; Sawyer, Michael G; Zubrick, Stephen R

    2015-03-01

    The General Functioning 12-item subscale (GF12) of The McMaster Family Assessment Device (FAD) has been validated as a single index measure to assess family functioning. This study reports on the reliability and validity of using only the six positive items from the General Functioning subscale (GF6+). Existing data from two Western Australian studies, the Raine Study (RS) and the Western Australian Child Health Survey (WACHS), was used to analyze the psychometric properties of the GF6+ subscale. The results demonstrated that the GF6+ subscale had virtually equivalent psychometric properties and was able to identify almost all of the same families who had healthy or unhealthy levels of functioning as the full GF12 subscale. In consideration of the constraints faced by large-scale population-based surveys, the findings of this study support the use of a GF6+ subscale from the FAD, as a quick and effective tool to assess the overall functioning of families. © 2014 Family Process Institute.

  10. 40 CFR 86.240-94 - Exhaust sample analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust sample analysis. 86.240-94 Section 86.240-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1994 and Later Model Year Gasoline-Fueled New Light-Duty Vehicles, New Light-Duty Trucks and New Medium...

  11. A Lagrangian Simulation of Subsonic Aircraft Exhaust Emissions

    Science.gov (United States)

    Schoeberl, M. R.; Morris, G. A.

    1999-01-01

    To estimate the effect of subsonic and supersonic aircraft exhaust on the stratospheric concentration of NO(y), we employ a trajectory model initialized with air parcels based on the standard release scenarios. The supersonic exhaust simulations are in good agreement with 2D and 3D model results and show a perturbation of about 1-2 ppbv of NO(y) in the stratosphere. The subsonic simulations show that subsonic emissions are almost entirely trapped below the 380 K potential temperature surface. Our subsonic results contradict results from most other models, which show exhaust products penetrating above 380 K, as summarized. The disagreement can likely be attributed to an excessive vertical diffusion in most models of the strong vertical gradient in NO(y) that forms at the boundary between the emission zone and the stratosphere above 380 K. Our results suggest that previous assessments of the impact of subsonic exhaust emission on the stratospheric region above 380 K should be considered to be an upper bound.

  12. Acetylene and carbon monoxide oxidation over a Pt/Rh/CeO2/γ-Al2O3 automotive exhaust gas catalyst: kinetic modelling of transient experiments

    NARCIS (Netherlands)

    Harmsen, J.M.A.; Hoebink, J.H.B.J.; Schouten, J.C.

    2001-01-01

    The transient kinetics of acetylene (C2H2) conversion by oxygen over a commercial Pt/Rh/CeO2/¿-Al2O3 three-way catalyst have been modelled. Experiments to validate the model were carried out in a fixed-bed reactor with two separate inlets, enabling alternate feeding of acetylene and oxygen.

  13. Side branch absorber for exhaust manifold of two-stroke internal combustion engine

    Science.gov (United States)

    Harris, Ralph E [San Antonio, TX; Broerman, III, Eugene L.; Bourn, Gary D [Laramie, WY

    2011-01-11

    A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.

  14. Stability of memories of parental rearing among psychiatric inpatients: a replication based on EMBU subscales.

    Science.gov (United States)

    Richter, J; Eisemann, M

    2001-01-01

    With regard to information about parental rearing, retrospective data are exclusively available among adults. These data are vulnerable due to various biases. This study was performed in order to replicate the findings of overall stability of three perceived parental rearing factors of the EMBU (Swedish acronym for 'own memories of childhood upbringing') based on 14 rather detailed subscales. A consecutive sample of 220 depressive inpatients were investigated on admission and at discharge by means of the EMBU, the Beck Depression Inventory and the Dysfunctional Attitude Scale. Perceived parental rearing scores showed high stability despite clinically significant changes in the severity of depression, except for 'tolerance', 'guilt engendering', 'performance orientation' and 'shaming' parenting with probable gender-specific effects which were found to covary with dysfunctional attitudes. Recall of parenting should be taken as a subjective truth when it is assessed by standardised behaviour-oriented questionnaires like the EMBU. Copyright 2002 S. Karger AG, Basel

  15. The reliability paradox of the Parent-Child Conflict Tactics Corporal Punishment Subscale.

    Science.gov (United States)

    Lorber, Michael F; Slep, Amy M Smith

    2018-02-01

    In the present investigation we consider and explain an apparent paradox in the measurement of corporal punishment with the Parent-Child Conflict Tactics Scale (CTS-PC): How can it have poor internal consistency and still be reliable? The CTS-PC was administered to a community sample of 453 opposite sex couples who were parents of 3- to 7-year-old children. Internal consistency was marginal, yet item response theory analyses revealed that reliability rose sharply with increasing corporal punishment, exceeding .80 in the upper ranges of the construct. The results suggest that the CTS-PC Corporal Punishment subscale reliably discriminates among parents who report average to high corporal punishment (64% of mothers and 56% of fathers in the present sample), despite low overall internal consistency. These results have straightforward implications for the use and reporting of the scale. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  16. The patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF)

    DEFF Research Database (Denmark)

    Crossley, Kay M; Macri, Erin M; Cowan, Sallie M

    2018-01-01

    with patellofemoral pain and/or osteoarthritis and 14 health and medical clinicians. Item reduction was performed using data from patellofemoral cohorts (n=138). We used the COnsesus-based Standards for the selection of health Measurements INstruments guidelines to evaluate reliability, validity, responsiveness......BACKGROUND: Patellofemoral pain and osteoarthritis are prevalent and associated with substantial pain and functional impairments. Patient-reported outcome measures (PROMs) are recommended for research and clinical use, but no PROMs are specific for patellofemoral osteoarthritis, and existing PROMs...... for patellofemoral pain have methodological limitations. This study aimed to develop a new subscale of the Knee injury and Osteoarthritis Outcome Score for patellofemoral pain and osteoarthritis (KOOS-PF), and evaluate its measurement properties. METHODS: Items were generated using input from 50 patients...

  17. Design of a Subscale Propellant Slag Evaluation Motor Using Two-Phase Fluid Dynamic Analysis

    Science.gov (United States)

    Whitesides, R. Harold; Dill, Richard A.; Purinton, David C.; Sambamurthi, Jay K.

    1996-01-01

    Small pressure perturbations in the Space Shuttle Reusable Solid Rocket Motor (RSRM) are caused by the periodic expulsion of molten aluminum oxide slag from a pool that collects in the aft end of the motor around the submerged nozzle nose during the last half of motor operation. It is suspected that some motors produce more slag than others due to differences in aluminum oxide agglomerate particle sizes that may relate to subtle differences in propellant ingredient characteristics such as particle size distributions or processing variations. A subscale motor experiment was designed to determine the effect of propellant ingredient characteristics on the propensity for slag production. An existing 5 inch ballistic test motor was selected as the basic test vehicle. The standard converging/diverging nozzle was replaced with a submerged nose nozzle design to provide a positive trap for the slag that would increase the measured slag weights. Two-phase fluid dynamic analyses were performed to develop a nozzle nose design that maintained similitude in major flow field features with the full scale RSRM. The 5 inch motor was spun about its longitudinal axis to further enhance slag collection and retention. Two-phase flow analysis was used to select an appropriate spin rate along with other considerations, such as avoiding bum rate increases due to radial acceleration effects. Aluminum oxide particle distributions used in the flow analyses were measured in a quench bomb for RSRM type propellants with minor variations in ingredient characteristics. Detailed predictions for slag accumulation weights during motor bum compared favorably with slag weight data taken from defined zones in the subscale motor and nozzle. The use of two-phase flow analysis proved successful in gauging the viability of the experimental program during the planning phase and in guiding the design of the critical submerged nose nozzle.

  18. Desulphurization of exhaust gases in chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Asperger, K.; Wischnewski, W.

    1981-01-01

    The sulfur content of exhaust gases can be reduced by: desulphurization of fuels; modification of processes; or treatment of resultant gases. In this paper a few selected examples from the chemical industry in the German Democratic Republic are presented. Using modified processes and treating the resultant gases, the sulphuric content of exhaust gases is effectively reduced. Methods to reduce the sulfur content of exhaust gases are described in the field of production of: sulphuric acid; viscose; fertilizers; and paraffin.

  19. Exhaust system of an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    1974-09-04

    A catalytic converter system for internal combustion engines is described that includes a means to maintain the catalyst temperature within a predetermined range for the efficient reduction of nitrogen oxides in the exhaust gas. Upstream of the catalytic converter, the exhaust pipe is encased in a structure such that a space is provided for the flow of a coolant around the exhaust pipe in response to the sensed catalytic temperature. A coolant control valve is actuated in response to the temperature sensor.

  20. 40 CFR 600.208-12 - Calculation of FTP-based and HFET-based fuel economy and carbon-related exhaust emission values...

    Science.gov (United States)

    2010-07-01

    ...-based fuel economy and carbon-related exhaust emission values for a model type. 600.208-12 Section 600... ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Regulations for 1977 and Later...-based and HFET-based fuel economy and carbon-related exhaust emission values for a model type. (a) Fuel...

  1. The Effect of Unemployment Insurance Exhaustion

    DEFF Research Database (Denmark)

    Lyk-Jensen, Stéphanie; Weatherall, Cecilie Dohlmann

    In this article we investigate how the long-term unemployed react to the threat of running out of unemployment insurance (UI) in a system in which other social benefits are available. The empirical analysis is based on very precise administrative records of unemployment spells in Denmark...... risk model to estimate the conditional probability of leaving unemployment to enter employment or receive other social benefits. We restrict our analysis to men aged 25-44 in 1998. Our results show that even for men having an initial UI entitlement for 4 years the threat of running out of UI indeed....... To identify the effect of UI exhaustion, we exploit the 1999 legislative change in the duration of benefit that progressively reduced regular UI entitlement from five to four years. According to time of entry into the UI system, all UI recipients had their potential UI period shortened. We use a competing...

  2. Diesel Exhaust Exposure, Wheezing and Sneezing

    Science.gov (United States)

    2012-01-01

    The rising incidence of allergic disorders in developed countries is unexplained. Exposure to traffic related air pollutants may be an important cause of wheezing and asthma in childhood. Experimental evidence from human studies suggests that diesel exhaust particles, constituents of fine particulate matter less than 2.5 microns (PM2.5), may act to enhance IgE mediated aeroallergen sensitization and Th2 directed cytokine responses. To date, epidemiologic investigations indicate that children living in close proximity to heavily travelled roads are more likely to be atopic and wheeze. The Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) birth cohort study was initiated to test the hypothesis that early high exposure to traffic related air pollutants is associated with early aeroallergen sensitization and allergic respiratory phenotypes. Using an exposure cohort design, more than 700 infants born to atopic parents were recruited at age 1 living either less than 400 meters (high traffic pollutant exposure) or greater than 1,500 meters (low exposure) from a major road. Children were medically evaluated and underwent skin prick testing with aeroallergen at screening, and re-evaluated sequentially at ages 1, 2, 3, 4, and 7. In this study, both proximity and land use regression (LUR) models of traffic air pollutant exposure have been assessed. Proximity to stop and go traffic with large concentrations of bus and truck traffic predicted persistent wheezing during infancy. The LUR model estimated elemental carbon attributable to traffic (ECAT) as a proxy for diesel exhaust particulate exposure. High ECAT was significantly associated with wheezing at age 1 as well as persistent wheezing at age 3. High mold exposure predicted a well defined asthma phenotype at age 7. PMID:22754710

  3. Incorporation of Emotional Labor in the Demand-Control-Support Model: The relation with Emotional Exhaustion and Personal Accomplishment in Nurses

    NARCIS (Netherlands)

    Näring, Gérard; van Droffelaar, Annemarie

    2008-01-01

    Nursing comprises interactions with patients which may require emotional labor. This study clarifies the relation of emotional labor with the three burnout dimensions within the context of the Demand Control Support model in nurses. We used the Dutch Questionnaire on Emotional Labor (D-QEL) to

  4. Exhaustion and Emotional Demands in China:A Large-Scale Investigation across Occupations

    Institute of Scientific and Technical Information of China (English)

    Kelly Z.Peng

    2017-01-01

    As the Chinese economy moves toward a market-based model,employees are likely to face more emotional demands and exhaustion at work.However,there are some unique aspects to the emotional demands of work in the Chinese cultural context.We investigate emotional demands and exhaustion in China with a large-scale sample across the six major occupations identified by the Holland classification system.Results show that incumbents of social and enterprising jobs face higher emotional demands.Unexpectedly,exhaustion differs significantly between conventional and other types of jobs.Building on the Job Demand-Resources (JD-R) model,job crafting and the cultural context,we propose that the nonlinear relationship of emotional demands and exhaustion exists only when emotional intelligence is low.Our study may inform practitioners and policy makers in Chinese enterprises about emotional demands and exhaustion for various occupations and the importance of selection and training programs in emotional intelligence.

  5. Measurements on Subscale Y-Ba-Cu-O Racetrack Coils at 77 K and Self-Field

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Caspi, S.; Cheng, D. W.; Dietderich, D. R.; Felice, H.; Ferracin, P.; Godeke, A.; Joseph, J. M.; Lizarazo, J.; Prestemon, S. O.; Sabbi, G.

    2009-10-19

    YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO) tapes carry significant amount of current at fields beyond the limit of Nb-based conductors. This makes the YBCO tapes a possible conductor candidate for insert magnets to increase the bore field of Nb{sub 3}Sn high-field dipoles. As an initial step of the YBCO insert technology development, two subscale racetrack coils were wound using Kapton-insulated commercial YBCO tapes. Both coils had two layers; one had 3 turns in each layer and the other 10 turns. The coils were supported by G10 side rails and waxed strips and not impregnated. The critical current of the coils was measured at 77 K and self-field. A 2D model considering the magnetic-field dependence of the critical current was used to estimate the expected critical current. The measured results show that both coils reached 80%-95% of the expected values, indicating the feasibility of the design concept and fabrication process.

  6. 40 CFR 1039.102 - What exhaust emission standards and phase-in allowances apply for my engines in model year 2014...

    Science.gov (United States)

    2010-07-01

    ... for any engine family in the 56-130 kW power category is 2.3 g/kW-hr for model years 2012 and 2013...-unit engine family in the 75-130 kW power category may be certified to meet the standards for PM, NMHC... the first four years of the Tier 4 standards for the applicable power category, as allowed in § 1039...

  7. Optimal Design of an Automotive Exhaust Thermoelectric Generator

    Science.gov (United States)

    Fagehi, Hassan; Attar, Alaa; Lee, Hosung

    2018-07-01

    The consumption of energy continues to increase at an exponential rate, especially in terms of conventional automobiles. Approximately 40% of the applied fuel into a vehicle is lost as waste exhausted to the environment. The desire for improved fuel efficiency by recovering the exhaust waste heat in automobiles has become an important subject. A thermoelectric generator (TEG) has the potential to convert exhaust waste heat into electricity as long as it is improving fuel economy. The remarkable amount of research being conducted on TEGs indicates that this technology will have a bright future in terms of power generation. The current study discusses the optimal design of the automotive exhaust TEG. An experimental study has been conducted to verify the model that used the ideal (standard) equations along with effective material properties. The model is reasonably verified by experimental work, mainly due to the utilization of the effective material properties. Hence, the thermoelectric module that was used in the experiment was optimized by using a developed optimal design theory (dimensionless analysis technique).

  8. Exhaustible-resource theory and the uranium market

    International Nuclear Information System (INIS)

    Hsieh, Y.L.

    1982-01-01

    Exhaustible-resource theory has been developed rapidly by economists since the OPEC shocks of 1973-1974 and the theory now provides a framework for analyzing the optimal production pattern for resource commodities. However, applications of the theory to particular markets, such as crude oil, have not provided accurate predictions due no doubt to theoretical problems in explaining exploration and discovery events, market organization changes, and uncertainty. This thesis investigated the uranium market in an effort to determine how well the exhaustible-resource theory explains the past price and quantity time paths of this energy resource, and what might be expected in the future. The exhaustible-resource theory was first developed in a form appropriate to an application to the uranium market. An econometric simulation model that combines the history of uranium price formation and the exhaustible-resource theory was developed to forecast future uranium prices. The model was designed not only to reflect the physical processes of drilling activities, changing reserves, production, and prices of uranium through individual equations, but also to account for the interaction of all these interrelationships at the same time

  9. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Thomas R.

    2009-12-31

    This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

  10. Optimal Design of an Automotive Exhaust Thermoelectric Generator

    Science.gov (United States)

    Fagehi, Hassan; Attar, Alaa; Lee, Hosung

    2018-04-01

    The consumption of energy continues to increase at an exponential rate, especially in terms of conventional automobiles. Approximately 40% of the applied fuel into a vehicle is lost as waste exhausted to the environment. The desire for improved fuel efficiency by recovering the exhaust waste heat in automobiles has become an important subject. A thermoelectric generator (TEG) has the potential to convert exhaust waste heat into electricity as long as it is improving fuel economy. The remarkable amount of research being conducted on TEGs indicates that this technology will have a bright future in terms of power generation. The current study discusses the optimal design of the automotive exhaust TEG. An experimental study has been conducted to verify the model that used the ideal (standard) equations along with effective material properties. The model is reasonably verified by experimental work, mainly due to the utilization of the effective material properties. Hence, the thermoelectric module that was used in the experiment was optimized by using a developed optimal design theory (dimensionless analysis technique).

  11. Study on the design of inlet and exhaust system of a stationary internal combustion engine

    International Nuclear Information System (INIS)

    Kesgin, Ugur

    2005-01-01

    The design and operational variables of inlet and exhaust systems are decisive to determine overall engine performance. The best engine overall performance can be obtained by proper design of the engine inlet and exhaust systems and by matching the correct turbocharger to the engine. This paper presents the results of investigations to design the inlet and exhaust systems of a stationary natural gas engine family. To do this, a computational model is verified in which zero dimensional phenomena within the cylinder and one dimensional phenomena in the engine inlet and exhaust systems are used. Using this engine model, the effects of the parameters of the inlet and exhaust systems on the engine performance are obtained. In particular, the following parameters are chosen: valve timing, valve diameter, valve lift profiles, diameter of the exhaust manifold, inlet and exhaust pipe lengths, and geometry of pipe junctions. Proper sizing of the inlet and exhaust pipe systems is achieved very precisely by these investigations. Also, valve timing is tuned by using the results obtained in this study. In general, a very high improvement potential for the engines studied here is presented

  12. How job demands affect absenteeism? The mediating role of work-family conflict and exhaustion.

    Science.gov (United States)

    Vignoli, Michela; Guglielmi, Dina; Bonfiglioli, Roberta; Violante, Francesco Saverio

    2016-01-01

    To investigate how psychosocial factors (such as job demands and work-family conflict) produce absenteeism in the workplace, using the health impairment process of the job demands-resources model. According to this model, job demands lead to burnout (often measured with the emotional exhaustion component), which in turn could lead to outcomes (such as absenteeism). Work-family conflict (WFC) was also studied, because of contradictory results collected in the existing literature on absenteeism in the workplace, regarding the role of WFC in causing absenteeism. Data were collected on 245 workers using both subjective (questionnaire on psychological risk factors and work-related health) and objective data (sickness leave frequency records). To test the hypothesis that job demands and WFC contribute to absenteeism in the workplace, a subsequent mediation analysis was used, which analysed both (a) the subsequent mediation of WFC and emotional exhaustion and (b) the separate roles played by the mediators proposed (WFC and emotional exhaustion). Job demands affect absenteeism through the subsequent mediation of WFC and emotional exhaustion. In addition, emotional exhaustion mediates the relationship between job demands and absenteeism, while WFC does not. In conclusion, subsequent mediation highlights the role of emotional exhaustion in causing absenteeism; in fact, when emotional exhaustion is included in the analysis, job demands are associated with higher levels of absenteeism. The results of this study suggest that without the concurrent contribution of emotional exhaustion, WFC does not influence absenteeism in the workplace. Our findings are useful for organizations that aim to reduce absenteeism.

  13. Flight Investigation to Determine the Effect of Jet Exhaust on Drag, Trim Characteristics, and Afterbody Pressures of a 0.125-Scale Rocket Model of the Mcdonnell F-101A Airplane

    Science.gov (United States)

    Kennedy, Thomas L.

    1956-01-01

    A flight investigation was conducted to determine the effect of jet exhaust on the drag, trim characteristics, and afterbody pressures on a 0.125-scale rocket model of the McDonnell F-101A airplance. Power-off data were obtained over a Mach number range of 1.04 to 1.9 and power-on data were obtained at a Mach number of about 1.5. The data indicated that with power-on the change in external drag coefficient was within the data accuracy and there was a decrease in trim angle of attack of 1.27 degrees with a corresponding decrease of 0.07 in lift coefficient. Correspondingly, pressure coefficients on the side and bottom of the fuselage indicated a positive increment near the jet exit. As the distance downstream of the jet exit increased, the increment on the bottom of the fuselage increased, whereas the increments on the side decreased to a negative peak.

  14. Model aerodynamic test results for two variable cycle engine coannular exhaust systems at simulated takeoff and cruise conditions. Comprehensive data report. Volume 3: Graphical data book 1

    Science.gov (United States)

    Nelson, D. P.

    1981-01-01

    A graphical presentation of the aerodynamic data acquired during coannular nozzle performance wind tunnel tests is given. The graphical data consist of plots of nozzle gross thrust coefficient, fan nozzle discharge coefficient, and primary nozzle discharge coefficient. Normalized model component static pressure distributions are presented as a function of primary total pressure, fan total pressure, and ambient static pressure for selected operating conditions. In addition, the supersonic cruise configuration data include plots of nozzle efficiency and secondary-to-fan total pressure pumping characteristics. Supersonic and subsonic cruise data are given.

  15. 49 CFR 393.83 - Exhaust systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Exhaust systems. 393.83 Section 393.83... NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.83 Exhaust systems. (a) Every motor... shall have a system to direct the discharge of such fumes. No part shall be located where its location...

  16. Vital exhaustion and risk for cancer

    DEFF Research Database (Denmark)

    Bergelt, Corinna; Christensen, Jane Hvarregaard; Prescott, Eva

    2005-01-01

    Vital exhaustion, defined as feelings of depression and fatigue, has previously been investigated mainly as a risk factor for cardiovascular disease. The authors investigated the association between depressive feelings and fatigue as covered by the concept of vital exhaustion and the risk...... for cancer....

  17. Vacuum exhaust duct used for thermonuclear device

    International Nuclear Information System (INIS)

    Tachikawa, Nobuo; Kondo, Mitsuaki; Honda, Tsutomu.

    1990-01-01

    The present invention concerns a vacuum exhaust duct used for a thermonuclear device. A cylindrical metal liners is lined with a gap to the inside of a vacuum exhaust duct main body. Bellows are connected to both ends of the metal liners and the end of the bellows is welded to the vacuum exhaust duct main body. Futher, a heater is mounted to the metal liner on the side of the vacuum exhaust duct main body, and the metal liner is heated by the heater to conduct baking for the vacuum exhaust duct main body. Accordingly, since there is no requirement for elevating the temperature of the vacuum exhaust duct upon conducting baking, the vacuum exhaust duct scarcely suffers substantial deformation due to heat expansion. Further, there is also no substantial deformation for the bellows disposed between the outer circumference of the vacuum vessel and a portion of a vacuum exhaust duct, so that the durability of the bellows is greatly improved. (I.S.)

  18. Vital exhaustion and risk for cancer

    DEFF Research Database (Denmark)

    Bergelt, Corinna; Christensen, Jane Hvarregaard; Prescott, Eva

    2005-01-01

    Vital exhaustion, defined as feelings of depression and fatigue, has previously been investigated mainly as a risk factor for cardiovascular disease. The authors investigated the association between depressive feelings and fatigue as covered by the concept of vital exhaustion and the risk...

  19. Overview of the testing activities on ITER sub-scale pre-compression rings

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Paolo, E-mail: paolo.rossi@enea.it [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Capobianchi, Mario; Crescenzi, Fabio; Massimi, Alberto; Mugnaini, Giampiero; Pizzuto, Aldo [Associazione EURATOM-ENEA sulla Fusione, C.R. Frascati, C.P. 65, 00044 Frascati, Rome (Italy); Knaster, Juan [ITER Organisation, Route de Vinon sur Verdon, 13115, St. Paul lez Durance (France); Rajainmaki, Hannu [FUSION FOR ENERGY, Josep Pla no. 2, Torres Diagonal Litoral Edificio B3, 08019 Barcelona (Spain)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer ENEA developed a high strength glass fiber-epoxy composite for ITER pre-compression rings. Black-Right-Pointing-Pointer High UTS values were obtained at RT on linear specimens (2200 MPa) and on scaled ring mock-ups (1550 MPa). Black-Right-Pointing-Pointer Creep tests showed very low creep strain and creep rates. Black-Right-Pointing-Pointer Long term tests showed no significant stress relaxation on the ring mock-ups. - Abstract: After a first R and D and testing activity to develop and characterize by tensile and creep tests a high strength glass fiber-epoxy composite as reference material for the manufacture of ITER pre-compression rings, ENEA designed and manufactured a dedicated testing facility and different sub-scale composite ring mock-ups in order to characterize their mechanical properties. The paper reports the results of the overall testing activities performed during the last years on a total number of eleven sub-scale pre-compression ring mock-ups manufactured by winding S2 glass fibers on a diameter of 1 m (1/5 of the full scale) both by vacuum pressure epoxy impregnation (VPI) and filament wet winding techniques (WW). The first three rings were manufactured by ENEA Frascati thanks to a particular VPI technique; one of them was used as base composite material to manufacture different sets of specimens for shear, compression and non destructive tests (NDT). Then, five other mock-ups were manufactured following ENEA VPI process and three using WW technique by two different industrial companies. The rings were tested in ENEA Frascati in a dedicated hydraulic testing machine consisting of 18 radial actuators working in position control with a total load capability of 1000 tons. The complete testing campaign consisted of six ultimate tensile strength (UTS) tests and four stress relaxation (SR) tests. The tests demonstrated that the composite (S2 glass-epoxy) is a valid and viable solution for the ITER pre

  20. Method for removing soot from exhaust gases

    Science.gov (United States)

    Suib, Steven L.; Dharmarathna, D. A. Saminda; Pahalagedara, Lakshitha R.

    2018-01-16

    A method for oxidizing soot from diesel exhaust gas from a diesel engine. The method involves providing a diesel particulate filter for receiving the diesel exhaust gas; coating a catalyst composition on the diesel particulate filter; and contacting the soot from the diesel exhaust gas with the catalyst coated diesel particulate filter at a temperature sufficient to oxidize the soot to carbon dioxide. The catalyst composition is a doped or undoped manganese oxide octahedral molecular sieve (OMS-2) material. A diesel exhaust gas treatment system that includes a diesel particulate filter for receiving diesel exhaust gas from a diesel engine and collecting soot; and a catalyst composition coated on the diesel particulate filter. The catalyst composition is a doped or undoped manganese oxide octahedral molecular sieve (OMS-2).

  1. Health effects of exhaust particles

    Energy Technology Data Exchange (ETDEWEB)

    Pihlava, T.; Uuppo, M.; Niemi, S.

    2013-11-01

    This report introduces general information about diesel particles and their health effects. The purpose of this report is to introduce particulate matter pollution and present some recent studies made regarding the health effects of particulate matter. The aim is not to go very deeply into the science, but instead to keep the text understandable for the average layman. Particulate matter is a complex mixture of extremely small particles and liquid droplets. These small particles are made up of a number of components that include for example acids, such as nitrates and sulphates, as well as organic chemicals, metals and dust particles from the soil. Particulate matter comes from several sources, such as transportation emissions, industrial emissions, forest fires, cigarette smoke, volcanic ash and climate variations. Particles are divided into coarse particles with diameters less than 10 ..m, fine particles with diameters smaller than 2.5 ..m and ultra-fine particles with diameters less than 0.1 ..m. The particulate matter in diesel exhaust gas is a highly complex mixture of organic, inorganic, solid, volatile and partly volatile compounds. Many of these particles do not form until they reach the air. Many carcinogenic compounds have been found in diesel exhaust gas and it is considered carcinogenic to humans. Particulate matter can cause several health effects, such as premature death in persons with heart or lung disease, cancer, nonfatal heart attacks, irregular heartbeat, aggravated asthma, decreased lung function and an increase in respiratory symptoms, such as irritation of the airways, coughing or difficulty breathing. It is estimated that in Finland about 1300 people die prematurely due to particles and the economic loss in the EU due to the health effects of particles can be calculated in the billions. Ultra-fine particles are considered to be the most harmful to human health. Ultrafine particles usually make the most of their quantity and surface area

  2. Depression Subscale of the Hospital Anxiety and Depression Scale applied preoperatively in spinal surgery

    Directory of Open Access Journals (Sweden)

    Asdrubal Falavigna

    2012-05-01

    Full Text Available OBJECTIVE: To evaluate the accuracy of the Depression Subscale of Hospital Anxiety and Depression Scale (HADS-D in spine surgery, comparing it to Beck Depression Inventory (BDI. METHODS: In a cross-sectional study, the HADS-D and the BDI were applied to patients undergoing spine surgery for lumbar (n=139 or cervical spondylosis (n=17. Spearman correlation tests for HADS-D and BDI were applied. The internal consistency of HADS-D was estimated by Cronbach's alpha coefficient. RESULTS: According to the BDI, the prevalence of depression was of 28.8% (n=45. The Spearman r coefficient between HADS-D and BDI was 0.714 (p10, there was a sensitivity of 71.1%, specificity of 95.4%, and positive likelihood-ratio of 15.78. CONCLUSIONS: HADS-D showed a strong correlation with BDI and good reliability. HADS-D is a good alternative for screening depression and assessing its severity.

  3. Subscale and Full-Scale Testing of Buckling-Critical Launch Vehicle Shell Structures

    Science.gov (United States)

    Hilburger, Mark W.; Haynie, Waddy T.; Lovejoy, Andrew E.; Roberts, Michael G.; Norris, Jeffery P.; Waters, W. Allen; Herring, Helen M.

    2012-01-01

    New analysis-based shell buckling design factors (aka knockdown factors), along with associated design and analysis technologies, are being developed by NASA for the design of launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s launch vehicle development and performance risks by reducing the reliance on testing, providing high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale level. This paper describes recent buckling test efforts at NASA on two different orthogrid-stiffened metallic cylindrical shell test articles. One of the test articles was an 8-ft-diameter orthogrid-stiffened cylinder and was subjected to an axial compression load. The second test article was a 27.5-ft-diameter Space Shuttle External Tank-derived cylinder and was subjected to combined internal pressure and axial compression.

  4. Evaluation of Neuropsychiatric Function in Phenylketonuria: Psychometric Properties of the ADHD Rating Scale-IV and Adult ADHD Self-Report Scale Inattention Subscale in Phenylketonuria.

    Science.gov (United States)

    Wyrwich, Kathleen W; Auguste, Priscilla; Yu, Ren; Zhang, Charlie; Dewees, Benjamin; Winslow, Barbara; Yu, Shui; Merilainen, Markus; Prasad, Suyash

    2015-06-01

    Previous qualitative research among adults and parents of children with phenylketonuria (PKU) has identified inattention as an important psychiatric aspect of this condition. The parent-reported ADHD Rating Scale-IV (ADHD RS-IV) and the Adult ADHD Self-Report Scale (ASRS) have been validated for measuring inattention symptoms in persons with attention-deficit/hyperactivity disorder (ADHD); however, their psychometric attributes for measuring PKU-related inattention have not been established. The primary objective of this investigation was to demonstrate the reliability, validity, and responsiveness of the ADHD RS-IV and ASRS inattention symptoms subscales in a randomized controlled trial of patients with PKU aged 8 years or older. A post hoc analysis investigated the psychometric properties (Rasch model fit, reliability, construct validity, and responsiveness) of the ADHD RS-IV and ASRS inattention subscales using data from a phase 3b, double-blind, placebo-controlled clinical trial in those with PKU aged 8 years or older. The Rasch results revealed good model fit, and reliability analyses revealed strong internal consistency reliability (α ≥ 0.87) and reproducibility (intraclass correlation coefficient ≥ 0.87) for both measures. Both inattention measures demonstrated the ability to discriminate between known groups (P < 0.001) created by the Clinical Global Impression-Severity scale. Correlations between the ADHD RS-IV and the ASRS with the Clinical Global Impression-Severity scale and the age-appropriate Behavior Rating Inventory of Executive Function Working Memory subscale were consistently moderate to strong (r ≥ 0.56). Similarly, results of the change score correlations were of moderate magnitude (r ≥ 0.43) for both measures when compared with changes over time in Behavior Rating Inventory of Executive Function Working Memory subscales. These findings of reliability, validity, and responsiveness of both the ADHD RS-IV and the ASRS inattention scales

  5. Parametric study on ship’s exhaust-gas behavior using computational fluid dynamics

    Directory of Open Access Journals (Sweden)

    Sunho Park

    2017-01-01

    Full Text Available The influence of design parameters related to a ship’s exhaust-gas behavior was investigated using computational fluid dynamics (CFD for an 8,000 TEU container carrier. To verify the numerical methods, the results were studied by comparing with experimental results. Several test conditions, i.e. various load conditions of ship, wind angle, deckhouse breadth, radar mast height, and exhaust-pipe height and shape were considered for a ship’s exhaust gas flow around the 8,000 TEU container carrier. The influence of the design parameters on contamination by the exhaust gas was quantified, after which the principal parameters to avoid contamination were selected. Finally, the design guideline of yP/H = 2 was suggested to avoid the contamination from the ship’s exhaust gas using the CFD results, model tests, and sea trials.

  6. Characteristic deterioration of ADAS-Jcog subscale scores and correlations with regional cerebral blood flow reductions in Alzheimer's disease.

    Science.gov (United States)

    Yoshii, Fumihito; Kawaguchi, Chikako; Kohara, Saori; Shimizu, Mie; Onaka, Hiroe; Ryo, Masafuchi; Takahashi, Wakoh

    2018-05-01

    The Alzheimer Disease Assessment Scale (Japanese version) cognitive subscale (ADAS-Jcog) is composed of a number of subscale tasks. However, it is not clear which subscale tasks are most susceptible to impairment in Alzheimer's disease (AD) or what is the relationship between reduction in regional cerebral blood flow (rCBF) and decreased ADAS-Jcog scores. Subjects were 32 AD patients, aged 52-86 years. We examined the relationship between subscale tasks that showed marked score changes and brain regions that showed reduced rCBF over a 2-year period. rCBF was measured by single-photon emission computed tomography (SPECT) with technetium-99m ethyl cysteinate dimer ( 99m Tc-ECD), and the SPECT imaging data were analyzed with the easy Z-score imaging system (eZIS) and voxel-based stereotactic extraction estimation (vbSEE) methods. Total score of ADAS-Jcog deteriorated from 19.5 ± 7.0 to 35.7 ± 15.2 after 2 years. Subscale scores were significantly worse in all fields, particularly in orientation, word recall, remembering test instructions, commands, constructional praxis, and ideational praxis, in that order. Significant correlations were found between (1) word recall and commands and rCBF in the left middle temporal lobe, (2) naming objects/fingers and rCBF in the left temporal (middle, inferior) lobe, and (3) constructional and ideational praxis and rCBF in the right parietal (superior, inferior) lobe, temporal (superior, middle) lobe, angular gyrus, and cingulate gyrus. We identified the brain regions associated with specifically impaired subscales of ADAS-Jcog during progressive deterioration of AD over 2 years.

  7. Design and Optimisation of Electrostatic Precipitator for Diesel Exhaust

    Science.gov (United States)

    Srinivaas, A.; Sathian, Samanyu; Ramesh, Arjun

    2018-02-01

    The principle of an industrially used emission reduction technique is employed in automotive diesel exhaust to reduce the diesel particulate emission. As the Emission regulation are becoming more stringent legislations have been formulated, due to the hazardous increase in the air quality index in major cities. Initially electrostatic precipitation principle and working was investigated. The High voltage requirement in an Electrostatic precipitator is obtained by designing an appropriate circuit in MATLAB -SIMULINK. Mechanical structural design of the new model after treatment device for the specific diesel exhaust was done. Fluid flow analysis of the ESP model was carried out using ANSYS CFX for optimized fluid with a reduced back pressure. Design reconsideration was done in accordance with fluid flow analysis. Accordingly, a new design is developed by considering diesel particulate filter and catalytic converter design to ESP model.

  8. Diesel exhaust controls and aftertreatment

    Energy Technology Data Exchange (ETDEWEB)

    Rubeli, B. [Natural Resources Canada, Sudbury, ON (Canada). CANMET Mining and Mineral Sciences Laboratories

    2009-07-01

    This presentation discussed the safe use of diesel fuels in underground mines, with particular reference to advanced technology engines and system technology options for mines. The use of diesel fuels underground requires well designed diesel engines with an effective preventive maintenance programs utilizing diesel emissions testing. The mines must have a well-engineered ventilation system and an adequate air quality monitoring system. An outline of diesel pollutant formation was included in the presentation. Diesel emission control technologies can address localized air quality problems and control emissions at the source. This presentation summarized the best available diesel emission control technologies for underground mines, namely diesel oxidation catalysts (DOC); diesel particulate filters (DPF); active diesel particulate filters (A-DPF); selective catalytic reduction (SCR); water scrubbers; and fume diluters. An emissions control plan using aftertreatment technology should target the vehicles that are the biggest contributors to diesel exhaust. Low sulphur fuel is a prerequisite for most emission control technologies. The successful control of emissions requires knowledge of the high emitting vehicle groups; an integrated ventilation and emission control technology application plan; ambient and tailpipe emissions testing; and training of operators and mechanics. tabs., figs.

  9. Exhaust gas recirculation system for an internal combustion engine

    Science.gov (United States)

    Wu, Ko-Jen

    2013-05-21

    An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

  10. A NEW EXHAUST VENTILATION SYSTEM DESIGN SOFTWARE

    Directory of Open Access Journals (Sweden)

    H. Asilian Mahabady

    2007-09-01

    Full Text Available A Microsoft Windows based ventilation software package is developed to reduce time-consuming and boring procedure of exhaust ventilation system design. This program Assure accurate and reliable air pollution control related calculations. Herein, package is tentatively named Exhaust Ventilation Design Software which is developed in VB6 programming environment. Most important features of Exhaust Ventilation Design Software that are ignored in formerly developed packages are Collector design and fan dimension data calculations. Automatic system balance is another feature of this package. Exhaust Ventilation Design Software algorithm for design is based on two methods: Balance by design (Static pressure balance and design by Blast gate. The most important section of software is a spreadsheet that is designed based on American Conference of Governmental Industrial Hygienists calculation sheets. Exhaust Ventilation Design Software is developed so that engineers familiar with American Conference of Governmental Industrial Hygienists datasheet can easily employ it for ventilation systems design. Other sections include Collector design section (settling chamber, cyclone, and packed tower, fan geometry and dimension data section, a unit converter section (that helps engineers to deal with units, a hood design section and a Persian HTML help. Psychometric correction is also considered in Exhaust Ventilation Design Software. In Exhaust Ventilation Design Software design process, efforts are focused on improving GUI (graphical user interface and use of programming standards in software design. Reliability of software has been evaluated and results show acceptable accuracy.

  11. Subscale Winged Rocket Development and Application to Future Reusable Space Transportation

    Directory of Open Access Journals (Sweden)

    Koichi YONEMOTO

    2018-03-01

    Full Text Available Kyushu Institute of Technology has been studying unmanned suborbital winged rocket called WIRES (WInged REusable Sounding rocket and its research subjects concerning aerodynamics, NGC (Navigation, Guidance and Control, cryogenic composite tanks etc., and conducting flight demonstration of small winged rocket since 2005. WIRES employs the original aerodynamic shape of HIMES (HIghly Maneuverable Experimental Sounding rocket studied by ISAS (Institute of Space and Astronautical Science of JAXA (Japan Aerospace Exploration Agency in 1980s. This paper presents the preliminary design of subscale non-winged and winged rockets called WIRES#013 and WIRES#015, respectively, that are developed in collaboration with JAXA, USC (University of Southern California, UTEP (University of Texas at El Paso and Japanese industries. WIRES#013 is a conventional pre-test rocket propelled by two IPA-LOX (Isopropyl Alcohol and Liquid Oxygen engines under development by USC. It has the total length of 4.6m, and the weight of 1000kg to reach the altitude of about 6km. The flight objective is validation of the telemetry and ground communication system, recovery parachute system, and launch operation of liquid engine. WIRES#015, which has the same length of WIRES#013 and the weight of 1000kg, is a NGC technology demonstrator propelled by a fully expander-cycle LOX-Methane engine designed and developed by JAXA to reach the altitude more than 6km. The flight tests of both WIRES#013 and WIRES#015 will be conducted at the launch facility of FAR (Friends of Amateur Rocketry, Inc., which is located at Mojave Desert of California in United States of America, in May 2018 and March 2019 respectively. After completion of WIRES#015 flight tests, the suborbital demonstrator called WIRES-X will be developed and its first flight test well be performed in 2020. Its application to future fully reusable space transportation systems, such as suborbital space tour vehicles and two

  12. Combined exposure of diesel exhaust particles and respirable Soufrière Hills volcanic ash causes a (pro-)inflammatory response in an in vitro multicellular epithelial tissue barrier model

    Science.gov (United States)

    Tomašek, Ines; Horwell, Claire J.; Damby, David; Barošová, Hana; Geers, Christoph; Petri-Fink, Alke; Rothen-Rutishauser, Barbara; Clift, Martin J. D.

    2016-01-01

    BackgroundThere are justifiable health concerns regarding the potential adverse effects associated with human exposure to volcanic ash (VA) particles, especially when considering communities living in urban areas already exposed to heightened air pollution. The aim of this study was, therefore, to gain an imperative, first understanding of the biological impacts of respirable VA when exposed concomitantly with diesel particles.MethodsA sophisticated in vitro 3D triple cell co-culture model of the human alveolar epithelial tissue barrier was exposed to either a single or repeated dose of dry respirable VA (deposited dose of 0.26 ± 0.09 or 0.89 ± 0.29 μg/cm2, respectively) from Soufrière Hills volcano, Montserrat for a period of 24 h at the air-liquid interface (ALI). Subsequently, co-cultures were exposed to co-exposures of single or repeated VA and diesel exhaust particles (DEP; NIST SRM 2975; 0.02 mg/mL), a model urban pollutant, at the pseudo-ALI. The biological impact of each individual particle type was also analysed under these precise scenarios. The cytotoxic (LDH release), oxidative stress (depletion of intracellular GSH) and (pro-)inflammatory (TNF-α, IL-8 and IL-1β) responses were assessed after the particulate exposures. The impact of VA exposure upon cell morphology, as well as its interaction with the multicellular model, was visualised via confocal laser scanning microscopy (LSM) and scanning electron microscopy (SEM), respectively.ResultsThe combination of respirable VA and DEP, in all scenarios, incited an heightened release of TNF-α and IL-8 as well as significant increases in IL-1β, when applied at sub-lethal doses to the co-culture compared to VA exposure alone. Notably, the augmented (pro-)inflammatory responses observed were not mediated by oxidative stress. LSM supported the quantitative assessment of cytotoxicity, with no changes in cell morphology within the barrier model evident. A direct interaction of the VA with all

  13. Modeling Economic Planning for Exhaustible Natural Resources ...

    African Journals Online (AJOL)

    ... relationship between initial speculative fund(s) and investment cost(s) in a project with finite life. We define a utility function for three categories of risk. The convolution of the utility function and decline income is our objective function to be ...

  14. Trees in urban street canyons and their impact on the dispersion of automobile exhausts

    OpenAIRE

    Gromke, Christof; Ruck, Bodo

    2007-01-01

    The aim of the present study is to clarify the influence of trees on the dispersion of automobile exhausts in urban street canyons. For this purpose, measurements have been performed with a small scale wind tunnel model of an idealized, isolated street canyon with model trees placed along the canyon center axis. Sulfur hexafluoride (SF6) was released from a line source embedded in the street surface, simulating vehicle exhaust emissions. The influence of various tree planting arrangements on ...

  15. Neurological signs and morphological cerebral changes in schizophrenia: An analysis of NSS subscales in patients with first episode psychosis.

    Science.gov (United States)

    Heuser, Mark; Thomann, Philipp A; Essig, Marco; Bachmann, Silke; Schröder, Johannes

    2011-05-31

    Neurological soft signs (NSS) comprise a broad range of minor motor and sensory deficits which are frequently found in schizophrenia. However, the cerebral changes underlying NSS are only partly understood. We therefore investigated the cerebral correlates of NSS by using magnetic resonance imaging (MRI) in 102 patients with first episode schizophrenia. NSS were assessed after remission of acute psychotic symptoms using the Heidelberg scale (HS), which consists of five NSS subscales ("motor coordination", "complex motor tasks", "orientation", "integrative functions", and "hard signs"). Correlations between NSS scores and cerebral changes were established by optimized voxel-based morphometry. NSS total scores were significantly associated with reduced gray matter densities in the precentral and postcentral gyri, the inferior parietal lobule and the inferior occipital gyrus. Both of the NSS subscales "motor coordination" and "complex motor tasks", referred to motor strip changes but showed differential correlations with parietal, insular, cerebellar or frontal sites, respectively. The NSS subscales "orientation" and "integrative functions" were associated with left frontal, parietal, and occipital changes or bihemispheric frontal changes, respectively. The NSS subscale "hard signs" was associated with deficits in the right cerebellum and right parastriate cortex. Repeated analyses for white matter changes revealed similar results. These findings confirm the associations between NSS and cerebral changes in areas important for motor and sensory functioning. This variety of cerebral sites corresponds to the heterogeneity of NSS and are consistent with the hypothesis that NSS reflect both a rather generalized cerebral dysfunction and localized deficits specific for particular signs. 2010 Elsevier Ireland Ltd. All rights reserved.

  16. A more in-depth interpretation of MMPI-2 in MS patients by using Harris and Lingoes subscales.

    Science.gov (United States)

    Incerti, Chiara C; Argento, Ornella; Pisani, Valerio; Magistrale, Giuseppe; Sabatello, Ugo; Caltagirone, Carlo; Nocentini, Ugo

    2017-01-01

    Multiple Sclerosis (MS) is frequently associated with neuropsychiatric abnormalities. The aim of our study was to discriminate between psychosomatic disturbances and MS physically-related symptoms using the Harris-Lingoes subscales of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). Forty-six MS out-patients (35 females; mean age = 44.5); and 82 healthy volunteers (62 females; mean age = 46.5) were evaluated with MMPI-2 questionnaire. The frequency distribution of MMPI-2 clinical scales with high scores (> = 65) and the related Harris-Lingoes subscales were analyzed for both MS patients and healthy control subjects. Data analysis showed elevated scores in 47.8% of the patients mainly on MMPI-2 clinical scales 1, 2, and 3. The Harris-Lingoes subscales analysis allowed us to isolate and identify physical symptoms contributing to elevation of MMPI-2 clinical scales, reduce the occurrence of false positives (MMPI-2 clinical scales elevations mainly due to MS physical disability) and provide a more detailed description of psycho-emotional symptoms of MS patients. In conclusion, our study shows the utility of Harris-Lingoes subscales analysis when MMPI-2 is used for psychological assessment of MS patients.

  17. Validity of the Mania Subscale of the Diagnostic Assessment for the Severely Handicapped-II (DASH-II).

    Science.gov (United States)

    Matson, Johnny L.; Smiroldo, Brandi B.

    1997-01-01

    A study tested the validity of the Diagnostic Assessment for the Severely Handicapped-II (DASH-II) for determining the presence of mania (bipolar disorder) in 22 individuals with severe mental retardation. Results found the mania subscale to be internally consistent and able to be used to classify manic and control subjects accurately. (Author/CR)

  18. Comparison of behavioral activation subscales of Gray’s original reinforcement sensitivity theory in opioid and methamphetamine dependent patients

    Directory of Open Access Journals (Sweden)

    Amir Ghaderi

    2017-10-01

    Results: The methamphetamine-dependents group had a higher BAS-DR subscale score than the opioid dependent group (P0.05. The BAS-RR scores of the methamphetamine-dependents group were higher than the other two groups (P

  19. The subscales and short forms of the dizziness handicap inventory: are they useful for comparison of the patient groups?

    Science.gov (United States)

    Ardıç, Fazıl Necdet; Tümkaya, Funda; Akdağ, Beyza; Şenol, Hande

    2017-10-01

    Dizziness Handicap Inventory (DHI) is one of the most frequently used surveys for vertigo. The aim of the study was re-analyze the consistency of subscales and correlation between original and different short forms. The data of 2111 patients were analyzed. Original three subscales, screening form of DHI and short form of DHI were evaluated. The suitability of the data set for factor analysis and factor structure was analyzed with Kaiser-Meyer-Olkin (KMO) coefficient, Bartlett's Sphericity Test, and Varimax method. Pearson correlation analysis was performed. Factor analysis showed that two factor solutions are more prominent in our data. The factors proposed in different studies are not in harmony with each other. There is high correlation between the original and screening and short forms of DHI. This study indicated that the factor structure of the scale was not consistent. It is not advised to use subscale scores for comparison especially in international level. Therefore, total score should be used rather than the scores of the subscales. Using DHI screening form instead of original 25 questions is more convenient, because it is highly correlated with the original one and has fewer questions. Implications for rehabilitation Factor structure of the DHI is not consistent enough for comparison of the international studies. Total score of DHI is reliable. Using the screening version of DHI is better, because it is highly correlated with the original form and has fewer questions (10 questions).

  20. Symptom profiles of subsyndromal depression in disease clusters of diabetes, excess weight, and progressive cerebrovascular conditions: a promising new type of finding from a reliable innovation to estimate exhaustively specified multiple indicators–multiple causes (MIMIC models

    Directory of Open Access Journals (Sweden)

    Francoeur RB

    2016-12-01

    Full Text Available Richard B Francoeur School of Social Work, Adelphi University, Garden City, NY, USA Abstract: Addressing subsyndromal depression in cerebrovascular conditions, diabetes, and obesity reduces morbidity and risk of major depression. However, depression may be masked because self-reported symptoms may not reveal dysphoric (sad mood. In this study, the first wave (2,812 elders from the New Haven Epidemiological Study of the Elderly (EPESE was used. These population-weighted data combined a stratified, systematic, clustered random sample from independent residences and a census of senior housing. Physical conditions included progressive cerebrovascular disease (CVD; hypertension, silent CVD, stroke, and vascular cognitive impairment [VCI] and co-occurring excess weight and/or diabetes. These conditions and interactions (clusters simultaneously predicted 20 depression items and a latent trait of depression in participants with subsyndromal (including subthreshold depression (11≤ Center for Epidemiologic Studies Depression Scale [CES-D] score ≤27. The option for maximum likelihood estimation with standard errors that are robust to non-normality and non-independence in complex random samples (MLR in Mplus and an innovation created by the author were used for estimating unbiased effects from latent trait models with exhaustive specification. Symptom profiles reveal masked depression in 1 older males, related to the metabolic syndrome (hypertension–overweight–diabetes; silent CVD–overweight; and silent CVD–diabetes and 2 older females or the full sample, related to several diabetes and/or overweight clusters that involve stroke or VCI. Several other disease clusters are equivocal regarding masked depression; a couple do emphasize dysphoric mood. Replicating findings could identify subgroups for cost-effective screening of subsyndromal depression. Keywords: depression, diabetes, overweight, cerebrovascular disease, hypertension, metabolic

  1. Does parallel item content on WOMAC's Pain and Function Subscales limit its ability to detect change in functional status?

    Directory of Open Access Journals (Sweden)

    Kennedy Deborah M

    2004-06-01

    Full Text Available Abstract Background Although the Western Ontario and McMaster University Osteoarthritis Index (WOMAC is considered the leading outcome measure for patients with osteoarthritis of the lower extremity, recent work has challenged its factorial validity and the physical function subscale's ability to detect valid change when pain and function display different profiles of change. This study examined the etiology of the WOMAC's physical function subscale's limited ability to detect change in the presence of discordant changes for pain and function. We hypothesized that the duplication of some items on the WOMAC's pain and function subscales contributed to this shortcoming. Methods Two eight-item physical function scales were abstracted from the WOMAC's 17-item physical function subscale: one contained activities and themes that were duplicated on the pain subscale (SIMILAR-8; the other version avoided overlapping activities (DISSIMILAR-8. Factorial validity of the shortened measures was assessed on 310 patients awaiting hip or knee arthroplasty. The shortened measures' abilities to detect change were examined on a sample of 104 patients following primary hip or knee arthroplasty. The WOMAC and three performance measures that included activity specific pain assessments – 40 m walk test, stair test, and timed-up-and-go test – were administered preoperatively, within 16 days of hip or knee arthroplasty, and at an interval of greater than 20 days following the first post-surgical assessment. Standardized response means were used to quantify change. Results The SIMILAR-8 did not demonstrate factorial validity; however, the factorial structure of the DISSIMILAR-8 was supported. The time to complete the performance measures more than doubled between the preoperative and first postoperative assessments supporting the theory that lower extremity functional status diminished over this interval. The DISSIMILAR-8 detected this deterioration in functional

  2. Ground Testing a Nuclear Thermal Rocket: Design of a sub-scale demonstration experiment

    Energy Technology Data Exchange (ETDEWEB)

    David Bedsun; Debra Lee; Margaret Townsend; Clay A. Cooper; Jennifer Chapman; Ronald Samborsky; Mel Bulman; Daniel Brasuell; Stanley K. Borowski

    2012-07-01

    In 2008, the NASA Mars Architecture Team found that the Nuclear Thermal Rocket (NTR) was the preferred propulsion system out of all the combinations of chemical propulsion, solar electric, nuclear electric, aerobrake, and NTR studied. Recently, the National Research Council committee reviewing the NASA Technology Roadmaps recommended the NTR as one of the top 16 technologies that should be pursued by NASA. One of the main issues with developing a NTR for future missions is the ability to economically test the full system on the ground. In the late 1990s, the Sub-surface Active Filtering of Exhaust (SAFE) concept was first proposed by Howe as a method to test NTRs at full power and full duration. The concept relied on firing the NTR into one of the test holes at the Nevada Test Site which had been constructed to test nuclear weapons. In 2011, the cost of testing a NTR and the cost of performing a proof of concept experiment were evaluated.

  3. Power and particle exhaust in tokamaks

    International Nuclear Information System (INIS)

    Stambaugh, R.D.

    1998-01-01

    The status of power and particle exhaust research in tokamaks is reviewed in the light of ITER requirements. There is a sound basis for ITER's nominal design positions; important directions for further research are identified

  4. Soundproofed exhaust system; Gegen stoerenden Abgasschall. Akustik

    Energy Technology Data Exchange (ETDEWEB)

    Paul-Faerber, M.

    2008-03-15

    Acoustic emissions of heating systems are a nuisance, especially the humming noise of big heating boilers and cogeneration units. Noise reduction measures, e.g. with exhaust sound absorbers, should be considered already in the projecting stage. (orig.)

  5. Two phase exhaust for internal combustion engine

    Science.gov (United States)

    Vuk, Carl T [Denver, IA

    2011-11-29

    An internal combustion engine having a reciprocating multi cylinder internal combustion engine with multiple valves. At least a pair of exhaust valves are provided and each supply a separate power extraction device. The first exhaust valves connect to a power turbine used to provide additional power to the engine either mechanically or electrically. The flow path from these exhaust valves is smaller in area and volume than a second flow path which is used to deliver products of combustion to a turbocharger turbine. The timing of the exhaust valve events is controlled to produce a higher grade of energy to the power turbine and enhance the ability to extract power from the combustion process.

  6. Fuel consumption and exhaust emissions of aircrafts

    Energy Technology Data Exchange (ETDEWEB)

    Buechler, R. [Institute of Flightmechanics, Braunschweig (Germany)

    1997-12-31

    The reduction of contamination of sensitive atmospheric layers by improved flight planning steps, is investigated. Calculated results have shown, that a further development of flight track planning allows considerable improvements on fuel consumption and exhaust emissions. Even if air traffic will further increase, optimistic investigations forecast a reduction of the environmental damage by aircraft exhausts, if the effects of improved flight track arrangement and engine innovations will be combined. (R.P.) 4 refs.

  7. Chemical processes in the turbine and exhaust nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Lukachko, S P; Waitz, I A [Massachusetts Inst. of Tech., Cambridge, MA (United States). Aero-Environmental Lab.; Miake-Lye, R C; Brown, R C; Anderson, M R [Aerodyne Research, Inc., Billerica, MA (United States); Dawes, W N [University Engineering Dept., Cambridge (United Kingdom). Whittle Lab.

    1998-12-31

    The objective is to establish an understanding of primary pollutant, trace species, and aerosol chemical evolution as engine exhaust travels through the nonuniform, unsteady flow fields of the turbine and exhaust nozzle. An understanding of such processes is necessary to provide accurate inputs for plume-wake modeling efforts and is therefore a critical element in an assessment of the atmospheric effects of both current and future aircraft. To perform these studies, a numerical tool was developed combining the calculation of chemical kinetics and one-, two-, or three-dimensional (1-D, 2-D, 3-D) Reynolds-averaged flow equations. Using a chemistry model that includes HO{sub x}, NO{sub y}, SO{sub x}, and CO{sub x} reactions, several 1-D parametric analyses were conducted for the entire turbine and exhaust nozzle flow path of a typical advanced subsonic engine to understand the effects of various flow and chemistry uncertainties on a baseline 1-D result. These calculations were also used to determine parametric criteria for judging 1-D, 2-D, and 3-D modeling requirements as well as to provide information about chemical speciation at the nozzle exit plane. (author) 9 refs.

  8. Chemical processes in the turbine and exhaust nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Lukachko, S.P.; Waitz, I.A. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Aero-Environmental Lab.; Miake-Lye, R.C.; Brown, R.C.; Anderson, M.R. [Aerodyne Research, Inc., Billerica, MA (United States); Dawes, W.N. [University Engineering Dept., Cambridge (United Kingdom). Whittle Lab.

    1997-12-31

    The objective is to establish an understanding of primary pollutant, trace species, and aerosol chemical evolution as engine exhaust travels through the nonuniform, unsteady flow fields of the turbine and exhaust nozzle. An understanding of such processes is necessary to provide accurate inputs for plume-wake modeling efforts and is therefore a critical element in an assessment of the atmospheric effects of both current and future aircraft. To perform these studies, a numerical tool was developed combining the calculation of chemical kinetics and one-, two-, or three-dimensional (1-D, 2-D, 3-D) Reynolds-averaged flow equations. Using a chemistry model that includes HO{sub x}, NO{sub y}, SO{sub x}, and CO{sub x} reactions, several 1-D parametric analyses were conducted for the entire turbine and exhaust nozzle flow path of a typical advanced subsonic engine to understand the effects of various flow and chemistry uncertainties on a baseline 1-D result. These calculations were also used to determine parametric criteria for judging 1-D, 2-D, and 3-D modeling requirements as well as to provide information about chemical speciation at the nozzle exit plane. (author) 9 refs.

  9. Current sheets and pressure anisotropy in the reconnection exhaust

    International Nuclear Information System (INIS)

    Le, A.; Karimabadi, H.; Roytershteyn, V.; Egedal, J.; Ng, J.; Scudder, J.; Daughton, W.; Liu, Y.-H.

    2014-01-01

    A particle-in-cell simulation shows that the exhaust during anti-parallel reconnection in the collisionless regime contains a current sheet extending 100 inertial lengths from the X line. The current sheet is supported by electron pressure anisotropy near the X line and ion anisotropy farther downstream. Field-aligned electron currents flowing outside the magnetic separatrices feed the exhaust current sheet and generate the out-of-plane, or Hall, magnetic field. Existing models based on different mechanisms for each particle species provide good estimates for the levels of pressure anisotropy. The ion anisotropy, which is strong enough to reach the firehose instability threshold, is also important for overall force balance. It reduces the outflow speed of the plasma

  10. Current sheets and pressure anisotropy in the reconnection exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Le, A.; Karimabadi, H.; Roytershteyn, V. [SciberQuest, Inc., Del Mar, California 92014 (United States); Egedal, J. [University of Wisconsin–Madison, Madison, Wisconsin 53706 (United States); Ng, J. [PPPL, Princeton University, Princeton, New Jersey 08543 (United States); Scudder, J. [University of Iowa, Iowa City, Iowa 52242 (United States); Daughton, W.; Liu, Y.-H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-01-15

    A particle-in-cell simulation shows that the exhaust during anti-parallel reconnection in the collisionless regime contains a current sheet extending 100 inertial lengths from the X line. The current sheet is supported by electron pressure anisotropy near the X line and ion anisotropy farther downstream. Field-aligned electron currents flowing outside the magnetic separatrices feed the exhaust current sheet and generate the out-of-plane, or Hall, magnetic field. Existing models based on different mechanisms for each particle species provide good estimates for the levels of pressure anisotropy. The ion anisotropy, which is strong enough to reach the firehose instability threshold, is also important for overall force balance. It reduces the outflow speed of the plasma.

  11. 46 CFR 182.430 - Engine exhaust pipe installation.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Engine exhaust pipe installation. 182.430 Section 182... 100 GROSS TONS) MACHINERY INSTALLATION Specific Machinery Requirements § 182.430 Engine exhaust pipe... equipment might come in contact with an exhaust pipe. (b) Exhaust gas must not leak from the piping or any...

  12. 46 CFR 119.430 - Engine exhaust pipe installation.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Engine exhaust pipe installation. 119.430 Section 119... INSTALLATION Specific Machinery Requirements § 119.430 Engine exhaust pipe installation. (a) The design of all... an exhaust pipe. (b) Exhaust gas must not leak from the piping or any connections. The piping must be...

  13. 46 CFR 119.425 - Engine exhaust cooling.

    Science.gov (United States)

    2010-10-01

    ..., all engine exhaust pipes must be water cooled. (1) Vertical dry exhaust pipes are permissible if installed in compliance with §§ 116.405(c) and 116.970 of this chapter. (2) Horizontal dry exhaust pipes are...) They are installed in compliance with §§ 116.405(c) and 116.970 of this chapter. (b) The exhaust pipe...

  14. Thermal analysis on x-ray tube for exhaust process

    Science.gov (United States)

    Kumar, Rakesh; Rao Ratnala, Srinivas; Veeresh Kumar, G. B.; Shivakumar Gouda, P. S.

    2018-02-01

    It is great importance in the use of X-rays for medical purposes that the dose given to both the patient and the operator is carefully controlled. There are many types of the X- ray tubes used for different applications based on their capacity and power supplied. In present thesis maxi ray 165 tube is analysed for thermal exhaust processes with ±5% accuracy. Exhaust process is usually done to remove all the air particles and to degasify the insert under high vacuum at 2e-05Torr. The tube glass is made up of Pyrex material, 95%Tungsten and 5%rhenium is used as target material for which the melting point temperature is 3350°C. Various materials are used for various parts; during the operation of X- ray tube these waste gases are released due to high temperature which in turn disturbs the flow of electrons. Thus, before using the X-ray tube for practical applications it has to undergo exhaust processes. Initially we build MX 165 model to carry out thermal analysis, and then we simulate the bearing temperature profiles with FE model to match with test results with ±5%accuracy. At last implement the critical protocols required for manufacturing processes like MF Heating, E-beam, Seasoning and FT.

  15. RNs and LPNs: emotional exhaustion and intention to leave.

    Science.gov (United States)

    Havaei, Farinaz; MacPhee, Maura; Dahinten, V Susan

    2016-04-01

    To describe and compare registered nurse (RN) and licensed practical nurse (LPN) emotional exhaustion, intention to leave and reasons for leaving. Different skill mix/care delivery models are being used to address nurse shortages and rising health-care costs. Skill mix may include RNs and LPNs. More LPNs are being employed in areas, such as acute care, that have been previously staffed by all RNs. Little is known about nurse outcomes since the introduction of LPNs to acute care settings. This study was a cross-sectional correlational design. A stratified, random sample of acute care nurses completed surveys via Fluidsurveys. The survey was modelled after the RN4CAST nursing workforce survey. For both groups of nurses higher levels of emotional exhaustion were associated with intention to leave and workload was the most frequent reason cited for intention to leave. More RNs than LPNs cited career advancement as a reason to leave, and more LPNs than RNs identified poor salary as a reason to leave. Emotional exhaustion is linked to intention to leave health care. Nurse managers should address work environment factors associated with turnover intentions, such as professional development opportunities and shared decision-making. © 2015 John Wiley & Sons Ltd.

  16. Reducing drag of a commuter train, using engine exhaust momentum

    Science.gov (United States)

    Ha, Dong Keun

    The objective of this thesis was to perform numerical investigations of two different methods of injecting fluid momentum into the air flow above a commuter train to reduce its drag. Based on previous aerodynamic modifications of heavy duty trucks in improving fuel efficiency, two structural modifications were designed and applied to a Metrolink Services commuter train in the Los Angeles (LA) County area to reduce its drag and subsequently improve fuel efficiency. The first modification was an L-shaped channel, added to the exhaust cooling fan above the locomotive roof to divert and align the exhaust gases in the axial direction. The second modification was adding an airfoil shaped lid over the L-shape channel, to minimize the drag of the perturbed structure, and thus reduce the overall drag. The computational fluid dynamic (CFD) software CCM+ from CD-Adapco with the ?-? turbulence model was used for the simulations. A single train set which consists of three vehicles: one locomotive, one trailer car and one cab car were used. All the vehicles were modeled based on the standard Metrolink fleet train size. The wind speed was at 90 miles per hour (mph), which is the maximum speed for the Orange County Metrolink line. Air was used as the exhaust gas in the simulation. The temperature of the exhausting air emitting out of the cooling fan on the roof was 150 F and the average fan speed was 120 mph. Results showed that with the addition of the lid, momentum injection results in reduced flow separation and pressure recovery behind the locomotive, which reduces the overall drag by at least 30%.

  17. Performance and exhaust emissions of a biodiesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Canakci, Mustafa [Kocaeli University, Technical Education Faculty, 41380 Kocaeli (Turkey); Erdil, Ahmet [Kocaeli University, Engineering Faculty, 41040 Kocaeli (Turkey); Arcaklioglu, Erol [Kirikkale University, Engineering Faculty, 71450 Kirikkale (Turkey)

    2006-06-15

    In this study, the applicabilities of Artificial Neural Networks (ANNs) have been investigated for the performance and exhaust-emission values of a diesel engine fueled with biodiesels from different feedstocks and petroleum diesel fuels. The engine performance and emissions characteristics of two different petroleum diesel-fuels (No. 1 and No. 2), biodiesels (from soybean oil and yellow grease), and their 20% blends with No. 2 diesel fuel were used as experimental results. The fuels were tested at full load (100%) at 1400-rpm engine speed, where the engine torque was 257.6Nm. To train the network, the average molecular weight, net heat of combustion, specific gravity, kinematic viscosity, C/H ratio and cetane number of each fuel are used as the input layer, while outputs are the brake specific fuel-consumption, exhaust temperature, and exhaust emissions. The back-propagation learning algorithm with three different variants, single layer, and logistic sigmoid transfer function were used in the network. By using weights in the network, formulations have been given for each output. The network has yielded R{sup 2} values of 0.99 and the mean % errors are smaller than 4.2 for the training data, while the R{sup 2} values are about 0.99 and the mean % errors are smaller than 5.5 for the test data. The performance and exhaust emissions from a diesel engine, using biodiesel blends with No. 2 diesel fuel up to 20%, have been predicted using the ANN model. sing the ANN model. (author)

  18. A parametric design of compact exhaust manifold junction in heavy duty diesel engine using CFD

    OpenAIRE

    Naeimi Hessamedin; Domiry Ganji Davood; Gorji Mofid; Javadirad Ghasem; Keshavarz Mojtaba

    2011-01-01

    Nowadays, computational fluid dynamics codes (CFD) are prevalently used to simulate the gas dynamics in many fluid piping systems such as steam and gas turbines, inlet and exhaust in internal combustion engines. In this paper, a CFD software is used to obtain the total energy losses in adiabatic compressible flow at compact exhaust manifold junction. A steady state onedimensional adiabatic compressible flow with friction model has been applied to subtract the straight pipe friction loss...

  19. Exhaust purification with on-board ammonia production

    Science.gov (United States)

    Robel, Wade J [Peoria, IL; Driscoll, James Joshua [Dunlap, IL; Coleman, Gerald N [Peterborough, GB

    2008-05-13

    A system of ammonia production for a selective catalytic reduction system is provided. The system includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream may be converted into ammonia.

  20. Daily Emotional Labor, Negative Affect State, and Emotional Exhaustion: Cross-Level Moderators of Affective Commitment

    Directory of Open Access Journals (Sweden)

    Hyewon Kong

    2018-06-01

    Full Text Available Employees’ emotional-labor strategies, experienced affects, and emotional exhaustion in the workplace may vary over time within individuals, even within the same day. However, previous studies on these relationships have not highlighted their dynamic properties of these relationships. In addition, although the effects of surface and deep acting on emotional exhaustion have been investigated in emotional-labor research, empirical studies on these relationships still report mixed results. Thus, we suggest that moderators may affect the relationship between emotional labor and emotional exhaustion. Also, this study examines the relationship between emotional labor and emotional exhaustion within individuals by repeated measurements, and verifies the mediating effect of a negative affect state. Finally, our study confirms the moderating effects that affective commitment has on the relationship between emotional labor and emotional exhaustion. Data was collected from tellers who had a high degree of interaction with clients at banks based in South Korea. A total of 56 tellers participated in the survey and responded for five working days. A total of 616 data entries were collected from the 56 respondents. We used a hierarchical linear model (HLM to examine our hypothesis. The results showed that surface-acting emotional labor increases emotional exhaustion; furthermore, the relationship between surface acting emotional labor and emotional exhaustion is mediated by a negative affect state within individuals. In addition, this study verified that affective commitment buffers the negative effects that surface acting emotional labor has on emotional exhaustion. These results suggest that emotional labor is a dynamic process within individuals, and that emotional exhaustion caused by emotional labor differs among individuals, and is dependent upon factors such as the individual’s level of affective commitment.

  1. Rapid Genetic Adaptation during the First Four Months of Survival under Resource Exhaustion.

    Science.gov (United States)

    Avrani, Sarit; Bolotin, Evgeni; Katz, Sophia; Hershberg, Ruth

    2017-07-01

    Many bacteria, including the model bacterium Escherichia coli can survive for years within spent media, following resource exhaustion. We carried out evolutionary experiments, followed by whole genome sequencing of hundreds of evolved clones to study the dynamics by which E. coli adapts during the first 4 months of survival under resource exhaustion. Our results reveal that bacteria evolving under resource exhaustion are subject to intense selection, manifesting in rapid mutation accumulation, enrichment in functional mutation categories and extremely convergent adaptation. In the most striking example of convergent adaptation, we found that across five independent populations adaptation to conditions of resource exhaustion occurs through mutations to the three same specific positions of the RNA polymerase core enzyme. Mutations to these three sites are strongly antagonistically pleiotropic, in that they sharply reduce exponential growth rates in fresh media. Such antagonistically pleiotropic mutations, combined with the accumulation of additional mutations, severely reduce the ability of bacteria surviving under resource exhaustion to grow exponentially in fresh media. We further demonstrate that the three positions at which these resource exhaustion mutations occur are conserved for the ancestral E. coli allele, across bacterial phyla, with the exception of nonculturable bacteria that carry the resource exhaustion allele at one of these positions, at very high frequencies. Finally, our results demonstrate that adaptation to resource exhaustion is not limited by mutational input and that bacteria are able to rapidly adapt under resource exhaustion in a temporally precise manner through allele frequency fluctuations. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  2. The interplay between teamwork, clinicians' emotional exhaustion, and clinician-rated patient safety: a longitudinal study.

    Science.gov (United States)

    Welp, Annalena; Meier, Laurenz L; Manser, Tanja

    2016-04-19

    Effectively managing patient safety and clinicians' emotional exhaustion are important goals of healthcare organizations. Previous cross-sectional studies showed that teamwork is associated with both. However, causal relationships between all three constructs have not yet been investigated. Moreover, the role of different dimensions of teamwork in relation to emotional exhaustion and patient safety is unclear. The current study focused on the long-term development of teamwork, emotional exhaustion, and patient safety in interprofessional intensive care teams by exploring causal relationships between these constructs. A secondary objective was to disentangle the effects of interpersonal and cognitive-behavioral teamwork. We employed a longitudinal study design. Participants were 2100 nurses and physicians working in 55 intensive care units. They answered an online questionnaire on interpersonal and cognitive-behavioral aspects of teamwork, emotional exhaustion, and patient safety at three time points with a 3-month lag. Data were analyzed with cross-lagged structural equation modeling. We controlled for professional role. Analyses showed that emotional exhaustion had a lagged effect on interpersonal teamwork. Furthermore, interpersonal and cognitive-behavioral teamwork mutually influenced each other. Finally, cognitive-behavioral teamwork predicted clinician-rated patient safety. The current study shows that the interrelations between teamwork, clinician burnout, and clinician-rated patient safety unfold over time. Interpersonal and cognitive-behavioral teamwork play specific roles in a process leading from clinician emotional exhaustion to decreased clinician-rated patient safety. Emotionally exhausted clinicians are less able to engage in positive interpersonal teamwork, which might set in motion a vicious cycle: negative interpersonal team interactions negatively affect cognitive-behavioral teamwork and vice versa. Ultimately, ineffective cognitive

  3. Performance of Installed Cooking Exhaust Devices

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Brett C.; Delp, William W.; Apte, Michael G.; Price, Philip N.

    2011-11-01

    The performance metrics of airflow, sound, and combustion product capture efficiency (CE) were measured for a convenience sample of fifteen cooking exhaust devices, as installed in residences. Results were analyzed to quantify the impact of various device- and installation-dependent parameters on CE. Measured maximum airflows were 70% or lower than values noted on product literature for 10 of the devices. Above-the-cooktop devices with flat bottom surfaces (no capture hood) – including exhaust fan/microwave combination appliances – were found to have much lower CE at similar flow rates, compared to devices with capture hoods. For almost all exhaust devices and especially for rear-mounted downdraft exhaust and microwaves, CE was substantially higher for back compared with front burner use. Flow rate, and the extent to which the exhaust device extends over the burners that are in use, also had a large effect on CE. A flow rate of 95 liters per second (200 cubic feet per minute) was necessary, but not sufficient, to attain capture efficiency in excess of 75% for the front burners. A-weighted sound levels in kitchens exceeded 57 dB when operating at the highest fan setting for all 14 devices evaluated for sound performance.

  4. Engineering task plan for five portable exhausters

    International Nuclear Information System (INIS)

    Rensink, G.E.

    1997-01-01

    Exhausters will be employed to ventilate certain single-shell tanks (SSTs) during salt well pumping campaigns. Active ventilation is necessary to reduce the potential flammable gas inventory (LANL 1996a) in the dome space that may accumulate during steady-state conditions or during/after postulated episodic gas release events. The tanks described in this plan support the activities required to fabricate and test three 500 cfm portable exhausters in the 200 W area shops, and to procure, design, fabricate and test two 1000 cfm units. Appropriate Notice of Construction (NOC) radiological and toxic air pollutant permits will be obtained for the portable exhausters. The portable exhauster design media to be employed to support this task was previously developed for the 241-A-101 exhauster. The same design as A101 will be fabricated with only minor improvements to the design based upon operator input/lessons learned. The safety authorization basis for this program effort will follow SAD 36 (LANL 1996b), and each tank will be reviewed against this SAD for changes or updates. The 1000 cfm units will be designed by the selected offsite contractor according to the specification requirements in KHC-S-O490. The offsite units have been specified to utilize as many of the same components as the 500 cfm units to ensure a more cost effective operation and maintenance through the reduction of spare parts and additional procedures

  5. System for measuring engine exhaust constituents

    International Nuclear Information System (INIS)

    Carduner, K.R.; Colvin, A.D.; Leong, D.Y.W.

    1992-01-01

    This patent describes a system for measuring an automotive engine exhaust constituent. It comprises: a meter for determining the mass of air flowing through the engine and for generating an engine airflow signal corresponding to the airflow; sample handling apparatus; diluent adding means; processor means. This patent also describes a method for using an analyzer to determine the amount of lubricating oil consumed by an automotive engine. It comprises: determining the amount of sulfur dioxide within the room air being drawn into the engine; maintaining a constant total flow comprised of a constant fraction of the engine's exhaust gas and a diluent gas through the analyzer, while: determining the amount of sulfur dioxide contained within the engine's exhaust, determining the amount of sulfur dioxide contained within the engine's exhaust, while operating the engine on room air; determining an efficiency factor for the analyzer; and using the efficiency factor and the concentration of sulfur in the engine oil and the amounts of sulfur dioxide determined in steps a and d to determine the amount of lubrication oil leaving the engine through its exhaust

  6. Lightweight Exhaust Manifold and Exhaust Pipe Ducting for Internal Combustion Engines

    Science.gov (United States)

    Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

    1999-01-01

    An improved exhaust system for an internal combustion gasoline-and/or diesel-fueled engine includes an engine exhaust manifold which has been fabricated from carbon- carbon composite materials in operative association with an exhaust pipe ducting which has been fabricated from carbon-carbon composite materials. When compared to conventional steel. cast iron. or ceramic-lined iron paris. the use of carbon-carbon composite exhaust-gas manifolds and exhaust pipe ducting reduces the overall weight of the engine. which allows for improved acceleration and fuel efficiency: permits operation at higher temperatures without a loss of strength: reduces the "through-the wall" heat loss, which increases engine cycle and turbocharger efficiency and ensures faster "light-off" of catalytic converters: and, with an optional thermal reactor, reduces emission of major pollutants, i.e. hydrocarbons and carbon monoxide.

  7. Air flow quality analysis of modenas engine exhaust system

    Science.gov (United States)

    Shahriman A., B.; Mohamad Syafiq A., K.; Hashim, M. S. M.; Razlan, Zuradzman M.; Khairunizam W. A., N.; Hazry, D.; Afendi, Mohd; Daud, R.; Rahman, M. D. Tasyrif Abdul; Cheng, E. M.; Zaaba, S. K.

    2017-09-01

    The simulation process being conducted to determine the air flow effect between the original exhaust system and modified exhaust system. The simulations are conducted to investigate the flow distribution of exhaust gases that will affect the performance of the engine. The back flow pressure in the original exhaust system is predicted toward this simulation. The design modification to the exhaust port, exhaust pipe, and exhaust muffler has been done during this simulation to reduce the back flow effect. The new designs are introduced by enlarging the diameter of the exhaust port, enlarge the diameter of the exhaust pipe and created new design for the exhaust muffler. Based on the result obtained, there the pulsating flow form at the original exhaust port that will increase the velocity and resulting the back pressure occur. The result for new design of exhaust port, the velocity is lower at the valve guide in the exhaust port. New design muffler shows that the streamline of the exhaust flow move smoothly compare to the original muffler. It is proved by using the modification exhaust system, the back pressure are reduced and the engine performance can be improve.

  8. Particle exhaust studies in Tore Supra with a pump limiter

    International Nuclear Information System (INIS)

    Klepper, C.C.; Haste, G.R.; Horton, L.D.; Mioduszewski, P.K.; Uckan, T.; Bonnel, P.; Bruneau, J.L.; Chatelier, M.; Gil, C.; Grisolia, C.; Loarer, T.; Martin, G.; Pegourie, B.; Rodriguez, L.; Watkins, J.G.

    1990-01-01

    The aim of the Tore Supra pump limiter program is to study particle exhaust with a pump limiter system in long-pulse discharges with continuous pellet fueling and strong auxiliary heating. The pump limiter system consists of six vertical modules, located at the bottom of the machine, and one horizontal module at the outer midplane. The results presented here were obtained with the horizontal module only. This module was equipped with two titanium pumps with a total pumping speed of 100000 L/s. The instrumentation of the limiter included pressure gauges, a residual gas analyzer, Langmuir probes, a spectrometer viewing the neutralizer plate for H α and impurity measurements, and water calorimeters. All diagnostics have been commissioned and are operational. Initial results were obtained in low-density discharges, with no gas puffing during the shot. While only a modest effect on the plasma density was observed, large exhaust fluxes were measured in the pump limiter. The most likely source of this gas was outgassing of the graphite walls. Straightforward particle balance between the plasma efflux and the pump limiter exhaust, as applied in previous pump limiter experiments, did not apply. The core plasma and the edge plasma seemed to be largely decoupled and a multi-layer model is being developed to explain the experimental results. (orig.)

  9. Baking exhaustion device in thermonuclear device

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Mitsunori.

    1987-02-02

    Purpose: To rapidly remove tritium and impurity from the vacuum region in the access port of the baking exhaustion device in a thermonuclear device. Constitution: Each of the gaps at the boundary between a fixed shielding member and a blanket module and at the boundary between the blanket and a divertor is made extremely small so as to minimize the neutron streaming from plasmas. Accordingly, in the case of evacuating the vacuum region in the access port, the gap conductance is extremely poor and the exhaustion speed is low. Then, baking pipeways for flowing high temperature fluids are embedded to the surface layer at the position facing to the vacuum region and the plasma evacuation duct and the vacuum region are connected with an evacuation duct of the access port. By flowing high temperature fluids in the pipeways and conducting evacuation, baking exhaustion can be carried out rapidly. (Kamimura, M.).

  10. PUREX exhaust ventilation system installation test report

    International Nuclear Information System (INIS)

    Blackaby, W.B.

    1997-01-01

    This Acceptance Test Report validates the testing performed, the exceptions logged and resolved and certifies this portion of the SAMCONS has met all design and test criteria to perform as an operational system. The proper installation of the PUREX exhaust ventilation system components and wiring was systematically evaluated by performance of this procedure. Proper operation of PUREX exhaust fan inlet, outlet, and vortex damper actuators and limit switches were verified, using special test equipment, to be correct and installed wiring connections were verified by operation of this equipment

  11. Work stress and emotional exhaustion in nurses: the mediating role of internal locus of control.

    Science.gov (United States)

    Partlak Günüşen, Neslihan; Ustün, Besti; Erdem, Sabri

    2014-01-01

    Burnout is a major problem for nursing. There is a strong relationship between work stress and emotional exhaustion. Although studies report a negative correlation between the internal locus of control and emotional exhaustion and work stress, the number of studies available on the subject is limited. This study intends to examine the extent to which the relationship between work stress and emotional exhaustion is mediated by nurses' internal locus of control. The study adopted a cross-sectional survey design. The data were analyzed using structural equation modeling techniques. The study sample consisted of 347 nurses who worked in a university hospital in Izmir, Turkey and who agreed to participate in the study. The Work-Related Strain Inventory was used to evaluate the nurses' work stress level, Maslach Burnout Inventory was used to evaluate their emotional exhaustion levels, and the Locus of Control Scale was used to evaluate the internal locus of control. The variables of the study were based on the Neuman Systems Model. Work stress was positively related to internal locus of control (β3 = .21, p 0.1). Internal locus of control was negatively related to emotional exhaustion (β = -.14, p Work stress is directly (β = .87, p Work stress is directly (β = .87, p work stress was mediated, the impact of internal locus of control was limited. It is recommended that different variables be included in future studies so that they can mediate the relationship between work stress and emotional exhaustion.

  12. Principal Components Analyses of the MMPI-2 PSY-5 Scales. Identification of Facet Subscales

    Science.gov (United States)

    Arnau, Randolph C.; Handel, Richard W.; Archer, Robert P.

    2005-01-01

    The Personality Psychopathology Five (PSY-5) is a five-factor personality trait model designed for assessing personality pathology using quantitative dimensions. Harkness, McNulty, and Ben-Porath developed Minnesota Multiphasic Personality Inventory-2 (MMPI-2) scales based on the PSY-5 model, and these scales were recently added to the standard…

  13. Exhaust Gas Emissions from a Rotating Detonation-wave Engine

    Science.gov (United States)

    Kailasanath, Kazhikathra; Schwer, Douglas

    2015-11-01

    Rotating detonation-wave engines (RDE) are a form of continuous detonation-wave engines. They potentially provide further gains in performance than an intermittent or pulsed detonation-wave engine (PDE). The overall flow field in an idealized RDE, primarily consisting of two concentric cylinders, has been discussed in previous meetings. Because of the high pressures involved and the lack of adequate reaction mechanisms for this regime, previous simulations have typically used simplified chemistry models. However, understanding the exhaust species concentrations in propulsion devices is important for both performance considerations as well as estimating pollutant emissions. Progress towards addressing this need will be discussed in this talk. In this approach, an induction parameter model is used for simulating the detonation but a more detailed finite-chemistry model including NOx chemistry is used in the expansion flow region, where the pressures are lower and the uncertainties in the chemistry model are greatly reduced. Results show that overall radical concentrations in the exhaust flow are substantially lower than from earlier predictions with simplified models. The performance of a baseline hydrogen/air RDE increased from 4940 s to 5000 s with the expansion flow chemistry, due to recombination of radicals and more production of H2O, resulting in additional heat release. Work sponsored by the Office of Naval Research.

  14. Toxicological aspects of fuel and exhaust gas

    International Nuclear Information System (INIS)

    Avella, F.

    1993-01-01

    Some aspects concerning fuels (gasoline) and gas exhaust vehicle emissions toxicology are briefly examined in light of the results reported in recent literature on this argument. Many experimental studies carried out on animals and men turn out incomplete and do not allow thorough evaluations, for every aspect, of the risk to which men and the environment are subjected

  15. Application of plasma techniques for exhaust aftertreatment

    Czech Academy of Sciences Publication Activity Database

    Pospíšil, M.; Viden, I.; Šimek, Milan; Pekárek, S.

    2001-01-01

    Roč. 27, 1-4 (2001), s. 306-314 ISSN 0143-3369 R&D Projects: GA ČR GA202/99/1298 Institutional research plan: CEZ:AV0Z2043910 Keywords : Non-thermal plasma, elctrical discharge, exhaust aftertreatment Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.190, year: 2001

  16. Malaria drives T cells to exhaustion

    Directory of Open Access Journals (Sweden)

    Michelle N Wykes

    2014-05-01

    Full Text Available Malaria is a significant global burden but after >30 years of effort there is no vaccine on the market. While the complex life cycle of the parasite presents several challenges, many years of research have also identified several mechanisms of immune evasion by Plasmodium spp.. Recent research on malaria, has investigated the Programmed cell death-1 (PD-1 pathway which mediates exhaustion of T cells, characterized by poor effector functions and recall responses and in some cases loss of the cells by apoptosis. Such studies have shown exhaustion of CD4+ T cells and an unappreciated role for CD8+ T cells in promoting sterile immunity against blood stage malaria. This is because PD-1 mediates up to a 95% reduction in numbers and functional capacity of parasite-specific CD8+ T cells, thus masking their role in protection. The role of T cell exhaustion during malaria provides an explanation for the absence of sterile immunity following the clearance of acute disease which will be relevant to future malaria-vaccine design and suggests the need for novel therapeutic solutions. This review will thus examine the role of PD-1-mediated T cell exhaustion in preventing lasting immunity against malaria.

  17. Cooking exhaust systems for low energy dwellings

    NARCIS (Netherlands)

    Jacobs, P.; Borsboom, W.A.

    2017-01-01

    Especially in airtight low energy dwellings exhaust systems are of utmost importance as cooking can be a major source of PM2.5 exposure. Dwellings should be designed including facilities enabling extraction of at least 83 dm3/s (300 m3/h) directly to outside. Residents should be able to select an

  18. Assessing population exposures to motor vehicle exhaust.

    Science.gov (United States)

    Van Atten, Chris; Brauer, Michael; Funk, Tami; Gilbert, Nicolas L; Graham, Lisa; Kaden, Debra; Miller, Paul J; Bracho, Leonora Rojas; Wheeler, Amanda; White, Ronald H

    2005-01-01

    The need is growing for a better assessment of population exposures to motor vehicle exhaust in proximity to major roads and highways. This need is driven in part by emerging scientific evidence of adverse health effects from such exposures and policy requirements for a more targeted assessment of localized public health impacts related to road expansions and increasing commercial transportation. The momentum for improved methods in measuring local exposures is also growing in the scientific community, as well as for discerning which constituents of the vehicle exhaust mixture may exert greater public health risks for those who are exposed to a disproportionate share of roadway pollution. To help elucidate the current state-of-the-science in exposure assessments along major roadways and to help inform decision makers of research needs and trends, we provide an overview of the emerging policy requirements, along with a conceptual framework for assessing exposure to motor-vehicle exhaust that can help inform policy decisions. The framework includes the pathway from the emission of a single vehicle, traffic emissions from multiple vehicles, atmospheric transformation of emissions and interaction with topographic and meteorologic features, and contact with humans resulting in exposure that can result in adverse health impacts. We describe the individual elements within the conceptual framework for exposure assessment and discuss the strengths and weaknesses of various approaches that have been used to assess public exposures to motor vehicle exhaust.

  19. Exhaust gas treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Shibamura, Yokichi; Suda, Shoichi; Kobayashi, Toshiki

    1991-01-01

    Among global environmental problems, atmospheric pollution has been discussed since relatively old days, and various countermeasures have been taken, but recently in connection with acid rain, the efficient and economical treatment technology is demanded. As the denitration and desulfurization technology for the exhaust gas from the combustion of fossil fuel, the incineration of city trash and internal combustion engines, three is the treatment method by electron beam irradiation. By irradiating electron beam to exhaust gas, nitrogen oxides and sulfur oxides are oxidized to nitric acid and sulfuric acid, and by promoting the neutralization of these acids with injected alkali, harmless salts are recovered. This method has the merit that nitrogen oxides and surfur oxides can be removed efficiently with a single system. In this report, as for the exhaust gas treatment by electron beam irradiation, its principle, features, and the present status of research and development are described, and in particular, the research on the recent exhaust gas treatment in city trash incineration is introduced. This treatment method is a dry process, accordingly, waste water disposal is unnecessary. The reaction products are utilized as fertilizer, and waste is not produced. (K.I.)

  20. Aircraft Piston Engine Exhaust Emission Symposium

    Science.gov (United States)

    1976-01-01

    A 2-day symposium on the reduction of exhaust emissions from aircraft piston engines was held on September 14 and 15, 1976, at the Lewis Research Center in Cleveland, Ohio. Papers were presented by both government organizations and the general aviation industry on the status of government contracts, emission measurement problems, data reduction procedures, flight testing, and emission reduction techniques.

  1. Exhaust gas afterburner for internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Haertel, G

    1977-05-12

    The invention pertains to an exhaust gas afterburner for internal combustion engines, with an auxiliary fuel device arranged upstream from the afterburner proper and controlled by the rotational speed of the engine, which is additionally controlled by an oxygen or carbon monoxide sensor. The catalytic part of the afterburner, together with a rotochamber, is a separate unit.

  2. Comparative toxicity and mutagenicity of biodiesel exhaust

    Science.gov (United States)

    Biodiesel (BD) is commercially made from the transesterification of plant and animal derived oils. The composition of biodiesel exhaust (BE) depends on the type of fuel, the blend ratio and the engine and operating conditions. While numerous studies have characterized the health ...

  3. Identification of informative features for predicting proinflammatory potentials of engine exhausts.

    Science.gov (United States)

    Wang, Chia-Chi; Lin, Ying-Chi; Lin, Yuan-Chung; Jhang, Syu-Ruei; Tung, Chun-Wei

    2017-08-18

    The immunotoxicity of engine exhausts is of high concern to human health due to the increasing prevalence of immune-related diseases. However, the evaluation of immunotoxicity of engine exhausts is currently based on expensive and time-consuming experiments. It is desirable to develop efficient methods for immunotoxicity assessment. To accelerate the development of safe alternative fuels, this study proposed a computational method for identifying informative features for predicting proinflammatory potentials of engine exhausts. A principal component regression (PCR) algorithm was applied to develop prediction models. The informative features were identified by a sequential backward feature elimination (SBFE) algorithm. A total of 19 informative chemical and biological features were successfully identified by SBFE algorithm. The informative features were utilized to develop a computational method named FS-CBM for predicting proinflammatory potentials of engine exhausts. FS-CBM model achieved a high performance with correlation coefficient values of 0.997 and 0.943 obtained from training and independent test sets, respectively. The FS-CBM model was developed for predicting proinflammatory potentials of engine exhausts with a large improvement on prediction performance compared with our previous CBM model. The proposed method could be further applied to construct models for bioactivities of mixtures.

  4. Physical characterization of diesel exhaust nucleation mode particles

    Energy Technology Data Exchange (ETDEWEB)

    Lahde, T.

    2013-11-01

    An increasing concern of the adverse health effects of aerosol particles is forcing the combustion engine industry to develop engines with lower particle emissions. The industry has put most of their efforts into soot control and has achieved a significant reduction in diesel exhaust particle mass. Nevertheless, it is not clear that the large particles, dominating the mass, cause the harmfulness of the exhaust particles in the biological interaction. Nowadays, the harmful potential of diesel exhaust particles often connects with the particle surface area, and the view has turned to particle number below 100 nm size range. Unfortunately, the achieved low exhaust particle mass does not necessarily imply a low particle number. This text focuses on the physical characteristics of diesel exhaust nucleation model particles. The volatility characteristics and the electrical charge state of the particles are studied first. Second, the relation between the nonvolatile nucleation mode emissions and the soot, the nitrogen oxide (NO{sub x}) emissions and the engine parameters are covered. The nucleation mode particles had distinctively different physical characteristics with different after-treatment systems. The nucleation mode was volatile and electrically neutral with a diesel particle filter after-treatment system. Without an after-treatment system or with an after-treatment system with low particle removal efficiency, the nucleation mode was partly nonvolatile and included an electrical charge. The difference suggests different formation routes for the nucleation particles with different after-treatment systems. The existence of the nonvolatile nucleation mode particles also affected the soot mode charge state. The soot charge state was positively biased when the nonvolatile nucleation mode was detected but slightly negatively biased when the nonvolatile nucleation mode was absent. The nonvolatile nucleation mode was always negatively biased. This electrical charge

  5. High temperature sensors for exhaust diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Svenningstorp, Henrik

    2000-07-01

    One of the largest problems that we will have to deal with on this planet this millennium is to stop the pollution of our environment. In many of the ongoing works to reduce toxic emissions, gas sensors capable of enduring rough environments and high temperatures, would be a great tool. The different applications where sensors like this would be useful vary between everything from online measurement in the paper industry and food industry to measurement in the exhaust pipe of a car. In my project we have tested Schottky diodes and MlSiCFET sensor as gas sensors operating at high temperatures. The measurement condition in the exhaust pipe of a car is extremely tough, not only is the temperature high and the different gases quite harmful, there are also a lot of particles that can affect the sensors in an undesirable way. In my project we have been testing Schottky diodes and MlSiCFET sensors based on SiC as high temperature sensors, both in the laboratory with simulated exhaust and after a real engine. In this thesis we conclude that these sensors can work in the hostile environment of an engines exhaust. It is shown that when measuring in a gas mixture with a fixed I below one, where the I-value is controlled by the O{sub 2} concentration, a sensor with a catalytic gate metal as sensitive material respond more to the increased O{sub 2} concentration than the increased HC concentration when varying the two correspondingly. A number of different sensors have been tested in simulated exhaust towards NO{sub x}. It was shown that resistivity changes in the thin gate metal influenced the gas response. Tests have been performed where sensors were a part of a SCR system with promising results concerning NH{sub 3} sensitivity. With a working temperature of 300 deg C there is no contamination of the metal surface.

  6. Small rocket exhaust plume data

    Science.gov (United States)

    Chirivella, J. E.; Moynihan, P. I.; Simon, W.

    1972-01-01

    During recent cryodeposit tests with an 0.18-N thruster, the mass flux in the plume back field was measured for the first time for nitrogen, carbon dioxide, and a mixture of nitrogen, hydrogen, and ammonia at various inlet pressures. This mixture simulated gases that would be generated by a hydrazine plenum attitude propulsion system. The measurements furnish a base upon which to build a mathematical model of plume back flow that will be used in predicting the mass distribution in the boundary region of other plumes. The results are analyzed and compared with existing analytical predictions.

  7. Conflict between the work and family domains and exhaustion among vocationally active men and women.

    Science.gov (United States)

    Canivet, Catarina; Ostergren, Per-Olof; Lindeberg, Sara I; Choi, BongKyoo; Karasek, Robert; Moghaddassi, Mahnaz; Isacsson, Sven-Olof

    2010-04-01

    Exhaustion is consistently found to be more prevalent in women than in men. Women suffer from job strain more often, which may constitute a partial explanation for this phenomenon, but experienced shortcomings in combining work and family demands may also contribute to ill health. The aim of this study was to investigate, and analyse by gender, how work-related and family-related factors, as well as the interface between them, i.e. work-to-family conflict (WFC) and family-to-work conflict (FWC), are related to exhaustion. The study was cross-sectional with self-administered questionnaires assessing exposures and outcome with previously well-validated instruments. The participants were 2726 men and 2735 women, aged 45-64, vocationally active, and residing in Malmö, Sweden. Sixteen percent of the women and 8% of the men considered themselves exhausted. WFC, FWC, job strain, and low job support were all strongly correlated to exhaustion in both genders. In the multivariate analyses, adjusting for other work and family risk factors, WFC and FWC remained statistically significant risk factors for exhaustion in both men and women. Job strain, low job support, and having a somatic disorder were also independently associated with exhaustion. While WFC was more prevalent among men, it was more strongly associated with exhaustion in women than in men. In women, WFC and FWC contributed to a larger part of the explanatory power of the model, which amounted to 22% of the variance in women and 14% in men. The results imply that the concept of 'work stress' should be regarded in a wider context in order to understand gender related issues of exhaustion among vocationally active individuals. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. The patellofemoral pain and osteoarthritis subscale of the KOOS (KOOS-PF): development and validation using the COSMIN checklist.

    Science.gov (United States)

    Crossley, Kay M; Macri, Erin M; Cowan, Sallie M; Collins, Natalie J; Roos, Ewa M

    2017-03-03

    Patellofemoral pain and osteoarthritis are prevalent and associated with substantial pain and functional impairments. Patient-reported outcome measures (PROMs) are recommended for research and clinical use, but no PROMs are specific for patellofemoral osteoarthritis, and existing PROMs for patellofemoral pain have methodological limitations. This study aimed to develop a new subscale of the Knee injury and Osteoarthritis Outcome Score for patellofemoral pain and osteoarthritis (KOOS-PF), and evaluate its measurement properties. Items were generated using input from 50 patients with patellofemoral pain and/or osteoarthritis and 14 health and medical clinicians. Item reduction was performed using data from patellofemoral cohorts (n=138). We used the COnsesus-based Standards for the selection of health Measurements INstruments guidelines to evaluate reliability, validity, responsiveness and interpretability of the final version of KOOS-PF and other KOOS subscales. From an initial 80 generated items, the final subscale included 11 items. KOOS-PF items loaded predominantly on one factor, pain during activities that load the patellofemoral joint. KOOS-PF had good internal consistency (Cronbach's α 0.86) and adequate test-retest reliability (intraclass correlation coefficient 0.86). Hypothesis testing supported convergent, divergent and known-groups validity. Responsiveness was confirmed, with KOOS-PF demonstrating a moderate correlation with Global Rating of Change scores (r 0.52) and large effect size (Cohen's d 0.89). Minimal detectable change was 2.3 (groups) and 16 (individuals), while minimal important change was 16.4. There were no floor or ceiling effects. The 11-item KOOS-PF, developed in consultation with patients and clinicians, demonstrated adequate measurement properties, and is recommended for clinical and research use in patients with patellofemoral pain and osteoarthritis. © Article author(s) (or their employer(s) unless otherwise stated in the text of

  9. NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

    Science.gov (United States)

    Jordan, Thomas L.; Bailey, Roger M.

    2008-01-01

    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

  10. Quantification of vehicle fleet PM_1_0 particulate matter emission factors from exhaust and non-exhaust sources using tunnel measurement techniques

    International Nuclear Information System (INIS)

    Lawrence, Samantha; Sokhi, Ranjeet; Ravindra, Khaiwal

    2016-01-01

    Road tunnels act like large laboratories; they provide an excellent environment to quantify atmospheric particles emission factors from exhaust and non-exhaust sources due to their known boundary conditions. Current work compares the High Volume, Dichotomous Stacked Filter Unit and Partisol Air Sampler for coarse, PM_1_0 and PM_2_._5 particle concentration measurement and found that they do not differ significantly (p = 95%). PM_2_._5 fraction contributes 66% of PM_1_0 proportions and significantly influenced by traffic (turbulence) and meteorological conditions. Mass emission factors for PM_1_0 varies from 21.3 ± 1.9 to 28.8 ± 3.4 mg/vkm and composed of Motorcycle (0.0003–0.001 mg/vkm), Cars (26.1–33.4 mg/vkm), LDVs (2.4–3.0 mg/vkm), HDVs (2.2–2.8 mg/vkm) and Buses (0.1 mg/vkm). Based on Lawrence et al. (2013), source apportionment modelling, the PM_1_0 emission of brake wear (3.8–4.4 mg/vkm), petrol exhaust (3.9–4.5 mg/vkm), diesel exhaust (7.2–8.3 mg/vkm), re-suspension (9–10.4 mg/vkm), road surface wear (3.9–4.5 mg/vkm), and unexplained (7.2 mg/vkm) were also calculated. The current study determined that the combined non-exhaust fleet PM_1_0 emission factor (16.7–19.3 mg/vkm) are higher than the combined exhaust emission factor (11.1–12.8 mg/vkm). Thus, highlight the significance of non-exhaust emissions and the need for legislation and abatement strategies to reduce their contributions to ambient PM concentrations. - Highlights: • Calculations of exhaust/non-exhaust particulate emission factors using tunnel sampling and source apportionment techniques. • Non-exhaust emission dominates in the fine particle fraction, considered responsible for adverse human health impacts. • Emission factors for non-exhaust sources (e.g. tyre and brake) were calculated. • Fleet source PM_1_0 emission factor were also calculated, which can be used in dispersion modelling and health risk assessment. • Tukey mean

  11. A psychometric evaluation of the Diabetes Symptom Checklist-Revised (DSC-R cognitive distress, fatigue, hyperglycemia, and hypoglycemia subscales in patients with type 1 and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Naegeli AN

    2010-03-01

    Full Text Available April N Naegeli1, Timothy E Stump2, Risa P Hayes11Global Health Outcomes, Eli Lilly and Company, Indianapolis, IN, USA; 2Consultant, Indianapolis, IN, USAObjective: To explore the use of Diabetes Symptom Checklist-Revised (DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia subscales as measures of acute diabetesassociated symptoms in patients with both type 1 and 2 diabetes.Research design and methods: Our study was conducted in context of two international, multicenter, randomized clinical trials for inhaled insulin. Confirmatory factor analyses and assessments of reliability and construct validity were performed.Results: Study participants were 371 patients with type 2 (56% male; mean age, 57 years and 481 with type 1 diabetes (57% male, mean age, 40 years. In both populations a four-factor model was the best fit. Cronbach’s α ≥ 0.79 and intraclass correlation coefficient ≥0.63; subscales correlated (P ≤ 0.05 with measures of well-being and satisfaction (0.12 ≤ r ≤ 0.71. In patients with type 1 diabetes, three subscales correlated (P < 0.05 with A1C.Conclusions: The psychometric properties of the DSC-R Cognitive Distress, Fatigue, Hyperglycemia, and Hypoglycemia suggest they may be utilized in clinical trials as reliable and valid measures of acute symptoms of diabetes.Keywords: Diabetes Symptom Checklist-Revised, DSC-R, type 1 diabetes, type 2 diabetes, psychometric validation

  12. Optimization of Design of Steam Turbine Exhaust Conduits

    Directory of Open Access Journals (Sweden)

    A. S. Goldin

    2014-01-01

    Full Text Available Improving effectiveness turbine was and remains a key issue for today. In order to improve the efficiency of the turbine is necessary to reduce losses in the steam turbine exhaust conduit.This paper presents the design optimization exhaust conduit steam turbine K-27-2.9 produced by JSC «KTW» at the design stage. The aims of optimizing the design were: decreasing hydraulic resistance of the conduit, reduction of non-uniformity of the flow at the outlet of the conduit, equalizing steam flow ahead of the condenser tube bundle.The conduit models were made and flows in it were simulated in environment of the Solid Works and its application COSMOS Flo Works.As the initial conduit model was selected exhaust conduit of turbine PT-25/34-3.4 produced by JSC «KTW». Was obtained by the calculated velocity field at the outlet of the conduit. The analysis of the calculation results revealed the necessity of changes to the initial design of the conduit. The changes were accompanied by calculating currents flow in the conduit, and assessed the impact of design changes on the nature of the course. Further transformation of the construction of the conduit was held on the results of these calculations. Construction changes are not touched by the outer geometry of the conduit, and were introduced to meet technological.According to calculation results, conclusions were drawn and selected three versions of the conduit.Given are the research results for the initial conduit model and modified design versions. In order to evaluate the flow degree of irregularity the momentum factor (Bussinesku factor for outlet crosssection of the selected conduit design version. Analysis of the research results made it possible to determine optimum design of the exhaust conduit.Introducing the suggested alterations in the conduit design will result in improvement of heat exchange in the condenser, an increase in reliability of the tube bundle operation, a decrease in noise and

  13. Comparative prediction of nonepileptic events using MMPI-2 clinical scales, Harris Lingoes subscales, and restructured clinical scales.

    Science.gov (United States)

    Yamout, Karim Z; Heinrichs, Robin J; Baade, Lyle E; Soetaert, Dana K; Liow, Kore K

    2017-03-01

    The Minnesota Multiphasic Personality Inventory-2 (MMPI-2) is a psychological testing tool used to measure psychological and personality constructs. The MMPI-2 has proven helpful in identifying individuals with nonepileptic events/nonepileptic seizures. However, the MMPI-2 has had some updates that enhanced its original scales. The aim of this article was to test the utility of updated MMPI-2 scales in predicting the likelihood of non-epileptic seizures in individuals admitted to an EEG video monitoring unit. We compared sensitivity, specificity, and likelihood ratios of traditional MMPI-2 Clinical Scales against more homogenous MMPI-2 Harris-Lingoes subscales and the newer Restructured Clinical (RC) scales. Our results showed that the Restructured Scales did not show significant improvement over the original Clinical scales. However, one Harris-Lingoes subscale (HL4 of Clinical Scale 3) did show improved predictive utility over the original Clinical scales as well as over the newer Restructured Clinical scales. Our study suggests that the predictive utility of the MMPI-2 can be improved using already existing scales. This is particularly useful for those practitioners who are not invested in switching over to the newly developed MMPI-2 Restructured Form (MMPI-2 RF). Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Effects of rocket exhaust products in the thermosphere and ionsphere

    International Nuclear Information System (INIS)

    Zinn, J.; Sutherland, C.D.

    1980-02-01

    This paper reviews the current state of understanding of the problem of ionospheric F-layer depletions produced by chemical effects of the exhaust gases from large rockets, with particular emphasis on the Heavy Lift Launch Vehicles (HLLV) proposed for use in the construction of solar power satellites. The currently planned HLLV flight profile calls for main second-stage propulsion confined to altitudes below 124 km, and a brief orbit circularization maneuver at apogee. The second stage engines deposit 9 x 10 31 H 2 O and H 2 molecules between 74 and 124 km. Model computations show that they diffuse gradually into the ionospheric F region, where they lead to weak but widespread and persistent depletions of ionization and continuous production of H atoms. The orbit circularization burn deposits 9 x 10 29 exhaust molecules at about 480-km altitude. These react rapidly with the F2 region 0 + ions, leading to a substantial (factor-of-three) reduction in plasma density, which extends over a 1000- by 2000-km region and persists for four to five hours. For purposes of computer model verification, a computation is included representing the Skylab I launch, for which observational data exist. The computations and data are compared, and the computer model is described

  15. Children's Exhaustive Readings of Questions

    Science.gov (United States)

    Cremers, Alexandre; Tieu, Lyn; Chemla, Emmanuel

    2017-01-01

    Questions, just like plain declarative sentences, can give rise to multiple interpretations. As discussed by Spector & Egré (2015), among others, questions embedded under know are ambiguous between "weakly exhaustive" (WE), "intermediate exhaustive" (IE), and "strongly exhaustive" (SE) interpretations (for…

  16. 46 CFR 52.25-20 - Exhaust gas boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Exhaust gas boilers. 52.25-20 Section 52.25-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING POWER BOILERS Other Boiler Types § 52.25-20 Exhaust gas boilers. Exhaust gas boilers with a maximum allowable working pressure...

  17. Contextualizing Emotional Exhaustion and Positive Emotional Display : The Signaling Effects of Supervisors' Emotional Exhaustion and Service Climate

    NARCIS (Netherlands)

    Lam, Catherine K.; Huang, Xu; Janssen, Onne; Lam, K.C.

    In this study, we investigated how supervisors' emotional exhaustion and service climate jointly influence the relationship between subordinates' emotional exhaustion and their display of positive emotions at work. Using data from frontline sales employees and their immediate supervisors in a

  18. Two Swedish screening instruments for exhaustion disorder: cross-sectional associations with burnout, work stress, private life stress, and personality traits.

    Science.gov (United States)

    Persson, Roger; Österberg, Kai; Viborg, Njördur; Jönsson, Peter; Tenenbaum, Artur

    2017-06-01

    To examine the relationships of two screening instruments recently developed for assessment of exhaustion disorder (ED) with some other well-known inventories intended to assess ED-related concepts and self-reports of job demands, job control, job support, private life stressors, and personality factors. A cross-sectional population sample ( n = 1355) completed: the Karolinska Exhaustion Disorder Scale (KEDS), Self-reported Exhaustion Disorder Scale (s-ED), Shirom-Melamed Burnout Questionnaire (SMBQ), Utrecht Work Engagement Scale (UWES-9), Job Content Questionnaire (JCQ), Big Five Inventory (BFI), and items concerning family-to-work interference and stress in private life. Compared to participants without any indication of ED, participants classified as having ED on KEDS or s-ED had higher scores on all four SMBQ subscales, lower scores on the UWES-9 subscales vigor and dedication, higher JCQ job demands scores, lower JCQ job support scores, higher degrees of family-to-work interference and stress in private life, and higher BFI neuroticism and openness scores. In addition, participants classified as having ED on KEDS had lower scores on the UWES-9 absorption subscale, the JCQ job control scale, and lower BFI extraversion, agreeableness and conscientiousness scores, compared to the subgroup not classified as having ED. As expected, we observed an overall pattern of associations between the ED screening inventories KEDS and s-ED and measures of burnout, work engagement, job demands-control-support, stress in private life, family-to-work interference, and personality factors. The results suggest that instruments designed to assess burnout, work engagement, and ED share common ground, despite their conceptual differences.

  19. Noise study in laboratories with exhaust fans

    International Nuclear Information System (INIS)

    Shaikh, G.H.; Hashmi, R.; Shareef, A.

    2005-01-01

    Noise study has been carried out in 25 laboratories fitted with exhaust fans. We have studied A- Weighted equivalent sound pressure levels (dB(A) LAeJ and equivalent octave band sound pressure levels (dB L/sub eq/ in each of the laboratories surveyed. The data collected has been analyzed for Preferred Speech Interference Levels (PSIL). The results show that the interior noise levels in these laboratories vary from 59.6 to 72.2 dB(A) L/sub Aeq/, which are very high and much beyond the interior noise limits recommended for laboratories. Some ways and means to limit emission of high-level noise from exhaust fans are also discussed. (author)

  20. Investigation and design optimization of exhaust-based thermoelectric generator system for internal combustion engine

    International Nuclear Information System (INIS)

    Niu, Zhiqiang; Diao, Hai; Yu, Shuhai; Jiao, Kui; Du, Qing; Shu, Gequn

    2014-01-01

    Highlights: • A 3-D model for exhaust-based thermoelectric waste heat recovery is developed. • Various heat, mass and electric transfer characteristics are elucidated. • Channel size needs to be moderate to balance heat transfer and pressure drop. • Bafflers need to be placed at all locations near all TEG modules. • Baffler angle needs to be sufficiently large, especially for downstream locations. - Abstract: Thermoelectric generator (TEG) has attracted considerable attention for the waste heat recovery of internal combustion engine. In this study, a 3-D numerical model for engine exhaust-based thermoelectric generator (ETEG) system is developed. By considering the detailed geometry of thermoelectric generator (TEG) and exhaust channel, the various transport phenomena are investigated, and design optimization suggestions are given. It is found that the exhaust channel size needs to be moderate to balance the heat transfer to TEG modules and pressure drop along channel. Increasing the number of exhaust channels may improve the performance, however, since more space and TEG modules are needed, the system size and cost need to be considered as well. Although only placing bafflers at the channel inlet could increase the heat transfer coefficient for the whole channel, the near wall temperature downstream might decrease significantly, leading to performance degradation of the TEG modules downstream. To ensure effective utilization of hot exhaust gas, the baffler angle needs to be sufficiently large, especially for the downstream locations. Since larger baffler angles increase the pressure drop significantly, it is suggested that variable baffler angles, with the angle increasing along the flow direction, might be a middle course for balancing the heat transfer and pressure drop. A single ETEG design may not be suitable to all the engine operating conditions, and making the number of exhaust channels and baffler angle adjustable according to different engine

  1. Rare earth metals for automotive exhaust catalysts

    International Nuclear Information System (INIS)

    Shinjoh, Hirohumi

    2006-01-01

    The usage of rare earth metals for automotive exhaust catalysts is demonstrated in this paper. Rare earth metals have been widely used in automotive catalysts. In particular, three-way catalysts require the use of ceria compounds as oxygen storage materials, and lanthana as both a stabilizer of alumina and a promoter. The application for diesel catalysts is also illustrated. Effects of inclusion of rare earth metals in automotive catalysts are discussed

  2. On Gas Dynamics of Exhaust Valves

    OpenAIRE

    Winroth, Marcus

    2017-01-01

    With increasing effects of global warming, efforts are made to make transportation in general more fuel efficient. When it comes to internal combustion engines, the most common way to improve fuel efficiency is through ‘downsizing’. Downsizing means that a smaller engine (with lower losses and less weight) performs the task of a larger engine. This is accomplished by fitting the smaller engine with a turbocharger, to recover some of the energy in the hot exhaust gases. Such engine systems nee...

  3. Concept of Heat Recovery from Exhaust Gases

    Science.gov (United States)

    Bukowska, Maria; Nowak, Krzysztof; Proszak-Miąsik, Danuta; Rabczak, Sławomir

    2017-10-01

    The theme of the article is to determine the possibility of waste heat recovery and use it to prepare hot water. The scope includes a description of the existing sample of coal-fired boiler plant, the analysis of working condition and heat recovery proposals. For this purpose, a series of calculations necessary to identify the energy effect of exhaust temperature decreasing and transferring recovery heat to hot water processing. Heat recover solutions from the exhaust gases channel between boiler and chimney section were proposed. Estimation for the cost-effectiveness of such a solution was made. All calculations and analysis were performed for typical Polish conditions, for coal-fired boiler plant. Typicality of this solution is manifested by the volatility of the load during the year, due to distribution of heat for heating and hot water, determining the load variation during the day. Analysed system of three boilers in case of load variation allows to operational flexibility and adaptation of the boilers load to the current heat demand. This adaptation requires changes in the operating conditions of boilers and in particular assurance of properly conditions for the combustion of fuel. These conditions have an impact on the existing thermal loss and the overall efficiency of the boiler plant. On the boiler plant efficiency affects particularly exhaust gas temperature and the excess air factor. Increasing the efficiency of boilers plant is possible to reach by following actions: limiting the excess air factor in coal combustion process in boilers and using an additional heat exchanger in the exhaust gas channel outside of boilers (economizer) intended to preheat the hot water.

  4. Chemical laser exhaust pipe design research

    Science.gov (United States)

    Sun, Yunqiang; Huang, Zhilong; Chen, Zhiqiang; Ren, Zebin; Guo, Longde

    2016-10-01

    In order to weaken the chemical laser exhaust gas influence of the optical transmission, a vent pipe is advised to emissions gas to the outside of the optical transmission area. Based on a variety of exhaust pipe design, a flow field characteristic of the pipe is carried out by numerical simulation and analysis in detail. The research results show that for uniform deflating exhaust pipe, although the pipeline structure is cyclical and convenient for engineering implementation, but there is a phenomenon of air reflows at the pipeline entrance slit which can be deduced from the numerical simulation results. So, this type of pipeline structure does not guarantee seal. For the design scheme of putting the pipeline contract part at the end of the exhaust pipe, or using the method of local area or tail contraction, numerical simulation results show that backflow phenomenon still exists at the pipeline entrance slit. Preliminary analysis indicates that the contraction of pipe would result in higher static pressure near the wall for the low speed flow field, so as to produce counter pressure gradient at the entrance slit. In order to eliminate backflow phenomenon at the pipe entrance slit, concerned with the pipeline type of radial size increase gradually along the flow, flow field property in the pipe is analyzed in detail by numerical simulation methods. Numerical simulation results indicate that there is not reflow phenomenon at entrance slit of the dilated duct. However the cold air inhaled in the slit which makes the temperature of the channel wall is lower than the center temperature. Therefore, this kind of pipeline structure can not only prevent the leak of the gas, but also reduce the wall temperature. In addition, compared with the straight pipe connection way, dilated pipe structure also has periodic structure, which can facilitate system integration installation.

  5. Fronting and exhaustive exclusion in Biblical Hebrew

    African Journals Online (AJOL)

    Kate H

    48, 2017, 219-222 doi: 10.5774/48-0-292. Fronting and exhaustive exclusion in Biblical Hebrew. Christo H. J. van der Merwe. Department of Ancient Studies, University of Stellenbosch, South ... Merwe, Naudé and Kroeze 2017: 491-493). .... “And I will give him to the Lord all the days of his life, and no razor shall touch his.

  6. Dynamic Wind-Tunnel Testing of a Sub-Scale Iced S-3B Viking

    Science.gov (United States)

    Lee, Sam; Barnhart, Billy; Ratvasky, Thomas P.

    2012-01-01

    The effect of ice accretion on a 1/12-scale complete aircraft model of S-3B Viking was studied in a rotary-balance wind tunnel. Two types of ice accretions were considered: ice protection system failure shape and runback shapes that form downstream of the thermal ice protection system. The results showed that the ice shapes altered the stall characteristics of the aircraft. The ice shapes also reduced the control surface effectiveness, but mostly near the stall angle of attack. There were some discrepancies with the data with the flaps deflected that were attributed to the low Reynolds number of the test. Rotational and forced-oscillation studies showed that the effects of ice were mostly in the longitudinal forces, and the effects on the lateral forces were relatively minor.

  7. Particle and Power Exhaust in EAST

    Science.gov (United States)

    Wang, Liang; Ding, Fang; Yu, Yaowei; Gan, Kaifu; Liang, Yunfeng; Xu, Guosheng; Xiao, Bingjia; Sun, Youwen; Luo, Guangnan; Gong, Xianzu; Hu, Jiansheng; Li, Jiangang; Wan, Baonian; Maingi, Rajesh; Guo, Houyang; Garofalo, Andrea; EAST Team

    2017-10-01

    A total power injection up to 0.3GJ has been achieved in EAST long pulse USN operation with ITER-like water-cooling W-monoblock divertor, which has steady-state power exhaust capability of 10 MWm-2. The peak temperature of W target saturated at t = 12 s to the value T 500oC and a heat flux 3MWm-2was maintained. Great efforts to reduce heat flux and accommodate particle exhaust simultaneously have been made towards long pulse of 102s time scale. By exploiting the observation of Pfirsch-Schlüter flow direction in the SOL, the Bt direction with Bx ∇B away from the W divertor (more particles favor outer target in USN) was adopted along with optimizing the strike point location near the pumping slot, to facilitate particle and impurity exhaust with the top cryo-pump. By tailoring the 3D divertor footprint through edge magnetic topology change, the heat load was dispersed widely and thus peak heat flux and W sputtering was well controlled. Active feedback control of total radiative power with neon seeding was achieved within frad = 17-35%, exhibiting further potential for heat flux reduction with divertor and edge radiation. Other heat flux handling techniques, including quasi snowflake configuration, will also be presented.

  8. Trees in urban street canyons and their impact on the dispersion of automobile exhausts

    NARCIS (Netherlands)

    Gromke, C.B.; Ruck, B.

    2007-01-01

    The aim of the present study is to clarify the influence of trees on the dispersion of automobile exhausts in urban street canyons. For this purpose, measurements have been performed with a small scale wind tunnel model of an idealized, isolated street canyon with model trees placed along the canyon

  9. A GM (1, 1) Markov Chain-Based Aeroengine Performance Degradation Forecast Approach Using Exhaust Gas Temperature

    OpenAIRE

    Zhao, Ning-bo; Yang, Jia-long; Li, Shu-ying; Sun, Yue-wu

    2014-01-01

    Performance degradation forecast technology for quantitatively assessing degradation states of aeroengine using exhaust gas temperature is an important technology in the aeroengine health management. In this paper, a GM (1, 1) Markov chain-based approach is introduced to forecast exhaust gas temperature by taking the advantages of GM (1, 1) model in time series and the advantages of Markov chain model in dealing with highly nonlinear and stochastic data caused by uncertain factors. In this ap...

  10. Individual- and Organization-Level Work-to-Family Spillover Are Uniquely Associated with Hotel Managers' Work Exhaustion and Satisfaction.

    Science.gov (United States)

    Lee, Soomi; Davis, Kelly D; Neuendorf, Claudia; Grandey, Alicia; Lam, Chun Bun; Almeida, David M

    2016-01-01

    Building on the Conservation of Resources theory, this paper examined the unique and interactive associations of negative and positive work-to-family spillover (NWFS and PWFS, respectively) at the individual and organizational level with hotel managers' work exhaustion and satisfaction, beyond job demands and supervisors' leadership style. Guided by the levels of analysis framework, we first tested the unique associations of NWFS and PWFS with emotional exhaustion and job satisfaction at the individual level (571 hotel managers), beyond job demands supervisors' leadership style. Second, using multilevel modeling, we tested the climate effects of NWFS and PWFS on emotional exhaustion and job satisfaction aggregated at the organizational level (41 hotels). Third, we examined the role of the organizational climate of PWFS in the associations of individual-level NWFS with emotional exhaustion and job satisfaction. Beyond the effects of psychological job demands and supervisor's transformational leadership, at the individual level, hotel managers who experienced higher NWFS than other managers reported more exhaustion and lower job satisfaction, whereas those with higher PWFS reported less exhaustion and higher satisfaction. At the organizational level, working in hotels where the average level of NWFS was higher than other hotels was associated with feeling more exhaustion of the individual members; working in hotels with higher PWFS was associated with feeling less exhaustion. The negative link between individual-level NWFS and job satisfaction was buffered when organization-level PWFS was higher, compared to when it was lower. This study moves beyond a focus on traditional job characteristics, toward considering individual and organizational experiences in the work-family interface as unique predictors of work exhaustion and satisfaction. Strengths of the study include illuminating organizational work-family climate effects such that coworkers' shared experiences of

  11. Experimental Evaluation of Installed Cooking Exhaust Fan Performance

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Brett C.; Delp, William W.; Apte, Michael G.

    2010-11-01

    The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range (MOR) units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands. Performance assessment included measurement of airflow and sound levels across fan settings and experiments to quantify the contemporaneous capture efficiency for the exhaust generated by natural gas cooking burners.Capture efficiency is defined as the fraction of generated pollutants that are removed through the exhaust and thus not available for inhalation of household occupants. Capture efficiency (CE) was assessed for various configurations of burner use (e.g., single front, single back, combination of one front and one back, oven) and fan speed setting. Measured airflow rates were substantially lower than the levels noted in product literature for many of the units. This shortfall was observed for several units costing in excess of $1000. Capture efficiency varied widely (from<5percent to roughly 100percent) across devices and across conditions for some devices. As expected, higher capture efficiencies were achieved with higher fan settings and the associated higher air flow rates. In most cases, capture efficiencies were substantially higher for rear burners than for front burners. The best and most consistent performance was observed for open hoods that covered all cooktop burners and operated at higher airflow rates. The lowest capture efficiencies were measured when a front burner was used with a rear backdraft system or with lowest fan setting for above the range

  12. Investing exhaustible resource rents and the path of consumption

    International Nuclear Information System (INIS)

    Hamilton, K.; Hartwick, J.M.

    2005-01-01

    This study presented a brief analysis of the concept of maintaining capital intact in an economy with 2 capital goods: one produced, and one an exhaustible oil stock. Oil stock supplies a vital input flow to the economy every day. The authors characterized dollar-valued national wealth and income. The magnitude of net investment has become pivotal in measuring the sustainability of an economy. This study linked the investment of exhaustible resource rents to growth in a model with energy consumption varying through time, as in a model of optimal savings. Dollar-valued net national product was set out for the economy with the essential, but wasting oil stock. The study applied the principle of maintaining capital intact and locally unchanging consumption. The percentage change in net investment or genuine savings, relative to the market rate of interest, determines whether current consumption is rising, constant, or declining. In the case of utility discount rates, it was observed that at a point of locally unchanging consumption, the net investment equals the prevailing market rate of interest, and the level of net investment is negative. The consumption increases when the percentage change in net investment is lower than the market rate of interest, and the reverse is true when consumption decreases. The connection between zero net investment and constant consumption was clarified. The sign of current net investment was found to be a good indicator of the direction of national wealth and income. 15 refs

  13. Exhaust gas recirculation apparatus for internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Shigemori, M; Eguchi, N

    1975-01-07

    An exhaust gas recirculation device to reduce nitrogen oxides emission from internal combustion engines is described. The recirculation is achieved by employing a tube connecting between the exhaust pipe and intake tube. A throttle valve is installed within the exhaust pipe between the muffler and recirculation tube, and regulated by exhaust gas temperature. Whenever the gas temperature is high, the valve closes and increases the gas flow to the intake tube. A temperature sensor is installed within the exhaust pipe and controls a solenoid or magnetic air valve linking to the throttle valve through a relay. The recirculation tube can be cooled by a fan to improve the engine power.

  14. Exhaust gas recirculation in a homogeneous charge compression ignition engine

    Science.gov (United States)

    Duffy, Kevin P [Metamora, IL; Kieser, Andrew J [Morton, IL; Rodman, Anthony [Chillicothe, IL; Liechty, Michael P [Chillicothe, IL; Hergart, Carl-Anders [Peoria, IL; Hardy, William L [Peoria, IL

    2008-05-27

    A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

  15. Numerical investigation of a novel burner to combust anode exhaust gases of SOFC stacks

    Directory of Open Access Journals (Sweden)

    Pianko-Oprych Paulina

    2017-09-01

    Full Text Available The aim of the present study was a numerical investigation of the efficiency of the combustion process of a novel concept burner under different operating conditions. The design of the burner was a part of the development process of a complete SOFC based system and a challenging combination of technical requirements to be fulfilled. A Computational Fluid Dynamics model of a non-premixed burner was used to simulate combustion of exhaust gases from the anode region of Solid Oxide Fuel Cell stacks. The species concentrations of the exhaust gases were compared with experimental data and a satisfactory agreement of the conversion of hydrocarbons was obtained. This validates the numerical methodology and also proves applicability of the developed approach that quantitatively characterized the interaction between the exhaust gases and burner geometry for proper combustion modelling. Thus, the proposed CFD approach can be safely used for further numerical optimisation of the burner design.

  16. In situ measurements of HO{sub x} in super- and subsonic aircraft exhaust plumes

    Energy Technology Data Exchange (ETDEWEB)

    Hanisco, T F; Wennberg, P O; Cohen, R C; Anderson, J G [Harvard Univ., Cambridge, MA (United States). Dept. of Chemistry; Fahey, D W; Keim, E R; Gao, R S; Wamsley, R C; Donnelly, S G; Del Negro, L A [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Aeronomy Lab.; others, and

    1998-12-31

    Concentrations of HO{sub x} (OH and HO{sub 2}) have been obtained in the exhaust plumes of an Air France Concorde and a NASA ER-2 in the lower stratosphere and the NASA DC-8 in the upper troposphere using instruments aboard the NASA ER-2. These fast-time response in situ measurements are used in conjunction with simultaneous in situ measurements of other key exhaust species (NO, NO{sub 2}, NO{sub y}, H{sub 2}O, and CO) to analyze the emissions of HO{sub x} from each aircraft under a variety of conditions. The data are used to establish a general description of gas phase plume chemistry that is easily implemented in a photochemical model. This model is used to determine the amount of HO{sub x} emitted from the engines and the gas phase oxidation rates of nitrogen and sulfur species in the exhaust plumes. (author) 10 refs.

  17. [Job Demands-Resources, exhaustion and work engagement in a long-term care institution].

    Science.gov (United States)

    Conway, P M; Neri, L; Campanini, P; Francioli, L; Camerino, D; Punzi, S; Fichera, G P; Costa, G

    2012-01-01

    In this study, we aimed at testing the main hypotheses of the Job Demands-Resources model (JD-R) in a sample of employees (n = 205, mainly healthcare workers) of a long-term care institution located in Northern Italy. Hierarchical linear regression analyses show that almost all job demands considered were significantly associated with higher general psycho-physical exhaustion (beta ranging from 0.14 to 0.29), whereas more unfavourable scores in all job resources were associated with lower work engagement (from -0.27 to -0.51). However, also significant cross-over associations were observed, mainly between job resources and exhaustion, with effect sizes comparable with those found for the relationships between job demands and exhaustion. Hence, our study only partially supports the JD-R model. Implications of results for work-related stress management are finally discussed.

  18. In situ measurements of HO{sub x} in super- and subsonic aircraft exhaust plumes

    Energy Technology Data Exchange (ETDEWEB)

    Hanisco, T.F.; Wennberg, P.O.; Cohen, R.C.; Anderson, J.G. [Harvard Univ., Cambridge, MA (United States). Dept. of Chemistry; Fahey, D.W.; Keim, E.R.; Gao, R.S.; Wamsley, R.C.; Donnelly, S.G.; Del Negro, L.A. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Aeronomy Lab.; and others

    1997-12-31

    Concentrations of HO{sub x} (OH and HO{sub 2}) have been obtained in the exhaust plumes of an Air France Concorde and a NASA ER-2 in the lower stratosphere and the NASA DC-8 in the upper troposphere using instruments aboard the NASA ER-2. These fast-time response in situ measurements are used in conjunction with simultaneous in situ measurements of other key exhaust species (NO, NO{sub 2}, NO{sub y}, H{sub 2}O, and CO) to analyze the emissions of HO{sub x} from each aircraft under a variety of conditions. The data are used to establish a general description of gas phase plume chemistry that is easily implemented in a photochemical model. This model is used to determine the amount of HO{sub x} emitted from the engines and the gas phase oxidation rates of nitrogen and sulfur species in the exhaust plumes. (author) 10 refs.

  19. Study of reaction between water and exhaust gases from diesel engines used in underground mining

    Energy Technology Data Exchange (ETDEWEB)

    Mazukhina, S.I.; Kalabin, G.V.; Romanov, V.S.

    1988-05-01

    A method of mathematical simulation, based on the principle of local equilibrium of the kinetic components, was proposed for formulating and solving problems related to the combustion of fuel and the treatment of exhaust gases from a diesel engine in underground workings. Results of a study of the effects of exhaust gas quantity and composition on the reaction between the gases and water are presented. It is shown that the kinetic model correlates well with the equilibrium model, adequately describes the process, and gives a reliable picture of the changes over a period of time. The proposed method can be used to study the gas emission with different fuel mixtures and liquid neutralizing agents with a view to reducing the toxicity of diesel-engine exhaust gases.

  20. 5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-11

    The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22

  1. 5th international exhaust gas and particulate emissions forum. Proceedings; 5. Internationales Forum Abgas- und Partikelemissionen. Beitraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-11

    The Proceedings of the 5th International Exhaust Gas and Particulate Emissions Forum contains 22 printed contributions as well as a CD-ROM. The titles of them are: (1) Diesel Emissions Control in the United States - 2010 and Beyond; (2) The MBE90 commercial vehicle engine for EPA '07 emissions regulations; (3) Concepts for engines and exhaust-gas cleaning systems for heavy duty trucks of the future; (4) HD Engine Technology for Near-Zero Emissions and Lowest Cost of Ownership; (5) (Partially-) Homogeneous Diesel Combustion; (6) Exhaust gas sensors for NOx storage catalysts and ammonia-SCR systems; (7) Sensors for modern exhaust gas after-treatment systems; (8) New reducing agents for low NOx-SCR Techno-logy; (9) Exhaust gas Aftertreatment on Lean Burn Gasoline Direct Injection Engines: The System of TWC and NOx-Storage Catalyst; (10) New Platinum/Palladium based catalyzed filter technologies for future passenger car applications; (11) Development of a Roadway Hydrocarbon Sorption Model and Characterization of a Novel PM Generator; (12) Requirements for current and future particulate measurement instrumentation from the point of view of the Physikalisch-Technische Bundesanstalt; (13) Standardized dilution conditions for gravimetric PM sampling - measures to assure results that correlate; (14) Particle Counting according PMP; (15) Future high-confidence measurement of diesel particulate emissions for approval and development; (16) New developments in optical instrumentation for exhaust gas; (17) Simultaneous Detection of Gaseous and Particulate Exhaust Components by Photoacoustic Spectroscopy; (18) Boundaries of modern exhaust gas instrumentation; (19) Raising quality and reducing application effort through efficient data input to the particulate filter load model for a EURO5 diesel car; (20) Stop-start operation of diesel engines - modified require-ment for exhaust gas after-treatment?; (21) Particulates emission with Biodiesel B30 impact on CSF management; (22

  2. Engine with exhaust gas recirculation system and variable geometry turbocharger

    Science.gov (United States)

    Keating, Edward J.

    2015-11-03

    An engine assembly includes an intake assembly, an internal combustion engine defining a plurality of cylinders and configured to combust a fuel and produce exhaust gas, and an exhaust assembly in fluid communication with a first subset of the plurality of cylinders. Each of the plurality of cylinders are provided in fluid communication with the intake assembly. The exhaust assembly is provided in fluid communication with a first subset of the plurality of cylinders, and a dedicated exhaust gas recirculation system in fluid communication with both a second subset of the plurality of cylinders and with the intake assembly. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the second subset of the plurality of cylinders to the intake assembly. Finally, the engine assembly includes a turbocharger having a variable geometry turbine in fluid communication with the exhaust assembly.

  3. Design and Analysis of Subscale and Full-Scale Buckling-Critical Cylinders for Launch Vehicle Technology Development

    Science.gov (United States)

    Hilburger, Mark W.; Lovejoy, Andrew E.; Thornburgh, Robert P.; Rankin, Charles

    2012-01-01

    NASA s Shell Buckling Knockdown Factor (SBKF) project has the goal of developing new analysis-based shell buckling design factors (knockdown factors) and design and analysis technologies for launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale levels. This paper describes the design and analysis of three different orthogrid-stiffeNed metallic cylindrical-shell test articles. Two of the test articles are 8-ft-diameter, 6-ft-long test articles, and one test article is a 27.5-ft-diameter, 20-ft-long Space Shuttle External Tank-derived test article.

  4. The concurrent validity of the Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale in adolescent patients in an urban federally qualified health center.

    Science.gov (United States)

    Kelly, Sharon M; O'Grady, Kevin E; Gryczynski, Jan; Mitchell, Shannon Gwin; Kirk, Arethusa; Schwartz, Robert P

    2017-01-01

    The Problem Oriented Screening Instrument for Teenagers (POSIT) substance use/abuse subscale has been validated with high school students, adolescents with criminal justice involvement, and adolescent substance use treatment samples using the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III-R and DSM-IV. This study examines the concurrent validity of the POSIT's standard 17-item substance use/abuse subscale and a revised, shorter 11-item version using DSM-5 substance use disorder diagnoses. Adolescents (N = 525; 93% African American, 55% female) 12-17 years of age awaiting primary care appointments at a Federally Qualified Health Center in Baltimore, Maryland completed the 17-item POSIT substance use/abuse subscale and items from a modified World Mental Health Composite International Diagnostic Interview corresponding to DSM-5 alcohol use disorder (AUD) and cannabis use disorder (CUD). Receiver operating characteristic curves, sensitivities, and specificities were examined with DSM-5 AUD, CUD, and a diagnosis of either or both disorders for the standard and revised subscales using risk cutoffs of either 1 or 2 POSIT "yes" responses. For the 17-item subscale, sensitivities were generally high using either cutoff (range: 0.79-1.00), although a cutoff of 1 was superior (sensitivities were 1.00 for AUD, CUD, and for either disorder). Specificities were also high using either cutoff (range: 0.81-0.95) but were higher using a cutoff of 2. For the 11-item subscale, a cutoff of 1 yielded higher sensitivities than a cutoff of 2 (ranges for 1 and 2: 0.96-1.00 and 0.79-0.86, respectively). Specificities for this subscale were higher using a cutoff of 2 (ranges for 1 and 2: 0.82-0.89 and 0.89-0.96, respectively). Findings suggest that the POSIT's substance use/abuse subscale is a potentially useful tool for screening adolescents in primary care for AUD or CUD using a cutoff of 1 or 2. The briefer, revised subscale may be preferable to the standard subscale in

  5. Toward Distinguishing Woodsmoke and Diesel Exhaust in Ambient Particulate Matter

    International Nuclear Information System (INIS)

    Braun, A.; Huggins, F.; Kubatova, A.; Wirick, S.; Maricq, M.; Mun, B.; McDonald, J.; Kelly, K.; Shah, N.; Huffman, G.

    2008-01-01

    Particulate matter (PM) from biomass burning and diesel exhaust has distinct X-ray spectroscopic, carbon specific signatures, which can be employed for source apportionment. Characterization of the functional groups of a wide selection of PM samples (woodsmoke, diesel soot, urban air PM) was carried out using the soft X-ray spectroscopy capabilities at the synchrotron radiation sources in Berkeley (ALS) and Brookhaven (NSLS). The spectra reveal that diesel exhaust particulate (DEP) matter is made up from a semigraphitic solid core and soluble organic matter, predominantly with carboxylic functional groups. Woodsmoke PM has no or a less prevalent, graphitic signature, instead it contains carbon-hydroxyl groups. Using these features to apportion the carbonaceous PM in ambient samples we estimate that the relative contribution of DEP to ambient PM in an urban area such as Lexington, KY and St. Louis, MO is 7% and 13.5%, respectively. These values are comparable to dispersion modeling data from nonurban and urban areas in California, and with elemental carbon measurements in urban locations such as Boston, MA, Rochester, NY, and Washington, DC.

  6. Mutagenicity of diesel exhaust soot dispersed in phospholipid surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, W.; Keane, M.; Xing, S.; Harrison, J.; Gautam, M.; Ong, T.

    1994-06-01

    Organics extractable from respirable diesel exhaust soot particles by organic solvents have been known for some time to be direct acting frameshift mutagens in the Ames Salmonella typhimurium histidine reversion assay. Upon deposition in a pulmonary alveolus or respiratory bronchiole, respirable diesel soot particles will contact first the hypophase which is coated by and laden with surfactants. To model interactions of soot and pulmonary surfactant, the authors dispersed soots in vitro in the primary phospholipid pulmonary surfactant dipalmitoyl glycerophosphorylcholine (lecithin) (DPL) in physiological saline. They have shown that diesel soots dispersed in lecithin surfactant can express mutagenic activity, in the Ames assay system using S. typhimurium TA98, comparable to that expressed by equal amounts of soot extracted by dichloromethane/dimethylsulfoxide (DCM/DMSO). Here the authors report additional data on the same system using additional exhaust soots and also using two other phospholipids, dipalmitoyl glycerophosphoryl ethanolamine (DPPE), and dipalmitoyl phosphatidic acid (DPPA), with different ionic character hydrophilic moieties. A preliminary study of the surfactant dispersed soot in an eucaryotic cell test system also is reported.

  7. TCV experiments towards the development of a plasma exhaust solution

    Science.gov (United States)

    Reimerdes, H.; Duval, B. P.; Harrison, J. R.; Labit, B.; Lipschultz, B.; Lunt, T.; Theiler, C.; Tsui, C. K.; Verhaegh, K.; Vijvers, W. A. J.; Boedo, J. A.; Calabro, G.; Crisanti, F.; Innocente, P.; Maurizio, R.; Pericoli, V.; Sheikh, U.; Spolare, M.; Vianello, N.; the TCV Team; the EUROfusion MST1 Team

    2017-12-01

    Research towards a plasma exhaust solution for a fusion power plant aims at validating edge physics models, strengthening predictive capabilities and improving the divertor configuration. The TCV tokamak is extensively used to investigate the extent that geometric configuration modifications can affect plasma exhaust performance. Recent TCV experiments continue previous detachment studies of Ohmically heated L-mode plasmas in standard single-null configurations, benefitting from a range of improved diagnostic capabilities. Studies were extended to nitrogen seeding and an entire suite of alternative magnetic configurations, including flux flaring towards the target (X divertor), increasing the outer target radius (Super-X) and movement of a secondary x-point inside the vessel (X-point target) as well as the entire range of snowflake configurations. Nitrogen seeding into a snowflake minus configuration demonstrated a regime with strong radiation in the large region between the two x-points, confirming EMC3-Eirene simulations, and opening a promising path towards highly radiating regimes with limited adverse effects on core performance.

  8. A mixed methods study of emotional exhaustion: Energizing and depleting work within an innovative healthcare team.

    Science.gov (United States)

    Cain, Cindy L; Taborda-Whitt, Caitlin; Frazer, Monica; Schellinger, Sandra; White, Katie M; Kaasovic, Jason; Nelson, Brenda; Chant, Allison

    2017-11-01

    This mixed methods study documents emotional exhaustion experiences among care team members during the development of an innovative team approach for caring for adults with serious illness. A mixed methods study design was employed to examine depleting work experiences that may produce emotional exhaustion, and energizing aspects of the work that may increase meaningfulness of work, thus reducing emotional exhaustion. The population studied included team members involved in care for adults with serious illness (n = 18). Team members were surveyed quarterly over an 18-month period using the Maslach Burnout Inventory (MBI). The MBI measures burnout, defined as the inability to continue work because of the interactional toll of the work. Analyses of MBI data show that although overall levels of burnout are low, 89% of team members reported moderate/high levels of emotional exhaustion during at least one survey period. In order to understand the kinds of work experiences that may produce or ameliorate emotional exhaustion, qualitative interviews were also conducted with team members at the end of the 18-month period. Major qualitative findings indicate that disputes within the team, environmental pressures, and standardisation of meaningful work leave team members feeling depleted. Having authentic relationships with patients, working as a team, believing in the care model, and practicing autonomy and creativity help team members to restore their emotional energy. Supports for team members' well-being are critical for continued innovation. We conclude with recommendations for improving team members' well-being.

  9. EGNAS: an exhaustive DNA sequence design algorithm

    Directory of Open Access Journals (Sweden)

    Kick Alfred

    2012-06-01

    Full Text Available Abstract Background The molecular recognition based on the complementary base pairing of deoxyribonucleic acid (DNA is the fundamental principle in the fields of genetics, DNA nanotechnology and DNA computing. We present an exhaustive DNA sequence design algorithm that allows to generate sets containing a maximum number of sequences with defined properties. EGNAS (Exhaustive Generation of Nucleic Acid Sequences offers the possibility of controlling both interstrand and intrastrand properties. The guanine-cytosine content can be adjusted. Sequences can be forced to start and end with guanine or cytosine. This option reduces the risk of “fraying” of DNA strands. It is possible to limit cross hybridizations of a defined length, and to adjust the uniqueness of sequences. Self-complementarity and hairpin structures of certain length can be avoided. Sequences and subsequences can optionally be forbidden. Furthermore, sequences can be designed to have minimum interactions with predefined strands and neighboring sequences. Results The algorithm is realized in a C++ program. TAG sequences can be generated and combined with primers for single-base extension reactions, which were described for multiplexed genotyping of single nucleotide polymorphisms. Thereby, possible foldback through intrastrand interaction of TAG-primer pairs can be limited. The design of sequences for specific attachment of molecular constructs to DNA origami is presented. Conclusions We developed a new software tool called EGNAS for the design of unique nucleic acid sequences. The presented exhaustive algorithm allows to generate greater sets of sequences than with previous software and equal constraints. EGNAS is freely available for noncommercial use at http://www.chm.tu-dresden.de/pc6/EGNAS.

  10. A highly efficient six-stroke internal combustion engine cycle with water injection for in-cylinder exhaust heat recovery

    International Nuclear Information System (INIS)

    Conklin, James C.; Szybist, James P.

    2010-01-01

    A concept adding two strokes to the Otto or Diesel engine cycle to increase fuel efficiency is presented here. It can be thought of as a four-stroke Otto or Diesel cycle followed by a two-stroke heat recovery steam cycle. A partial exhaust event coupled with water injection adds an additional power stroke. Waste heat from two sources is effectively converted into usable work: engine coolant and exhaust gas. An ideal thermodynamics model of the exhaust gas compression, water injection and expansion was used to investigate this modification. By changing the exhaust valve closing timing during the exhaust stroke, the optimum amount of exhaust can be recompressed, maximizing the net mean effective pressure of the steam expansion stroke (MEP steam ). The valve closing timing for maximum MEP steam is limited by either 1 bar or the dew point temperature of the expansion gas/moisture mixture when the exhaust valve opens. The range of MEP steam calculated for the geometry of a conventional gasoline engine and is from 0.75 to 2.5 bars. Typical combustion mean effective pressures (MEP combustion ) of naturally aspirated gasoline engines are up to 10 bar, thus this concept has the potential to significantly increase the engine efficiency and fuel economy.

  11. A study of automobile exhaust noise preferences

    Science.gov (United States)

    Haire, Jay B.; Carney, Melinda J.; Cheenne, Dominique J.

    2005-04-01

    A study was conducted to investigate the relationship between preferences in automobile exhaust noise and the demographic factors of a listening jury. Noise samples of four different vehicles were recorded at idle as well as at 3000 RPM, and 1/3 octave sound spectra were acquired simultaneously. The recordings were presented to the jury using headphones and a preference survey was administered. Zwicker loudness was computed for all samples. Demographic factors such as gender, age, current and future vehicle ownership, were correlated to listening preferences, and unforeseen results were found, especially in regards to sport utility vehicles (SUV).

  12. Effect of Perceived Politics and Perceived Support on Bullying and Emotional Exhaustion: The Moderating Role of Type A Personality.

    Science.gov (United States)

    Naseer, Saima; Raja, Usman; Donia, Magda Bezerra Leite

    2016-07-03

    Recognizing that bullying can occur in varying degrees of severity, the current study suggest the importance of individual traits in individual perceptions of being targets of bullying and ensuing emotional exhaustion. The present study extends the work environment hypothesis and trait activation theory by a joint investigation of the mediating role of (a) workplace bullying in linking perceived organization politics and perceived organization support with emotional exhaustion and (b) the moderating role of Type A behavioral pattern in influencing the mediation. Using a field sample of 262 employees working in different organizations of Pakistan, this study tested a moderated mediation model. Results were consistent with the hypothesized model, in that workplace bullying mediated the relationship of perceived organization politics and perceived organization support with emotional exhaustion. Type A behavior moderated the perceived politics-bullying, perceived support-bullying, and bullying-emotional exhaustion relationships. The mediation of bullying varied with levels of Type A behavior in these relationships.

  13. Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

    OpenAIRE

    Galashov Nikolay; Tsibulskiy Svyatoslav; Mel’nikov Denis; Kiselev Alexandr; Gabdullina Al’bina

    2017-01-01

    The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG) of combined-cycle gas turbine (CCGT). Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion produ...

  14. Analysis of vibration of exhaust valve pipeline in nuclear power plant

    International Nuclear Information System (INIS)

    Tan Ping

    2005-01-01

    Pipeline system for conveying pressurized steam often operates under time-varying conditions due to the valve operations. This may cause vibration problems as a result the pipeline system suffered vibration damage. In this paper, a finite element formulation for the exhaust dynamic equations that include the effect of all pipe supports, and hangers is introduced and applied to the dynamic analysis of the pipeline system used in a nuclear power plant. the vibration response of steam-conveying pipeline induced by valve exhaust has been studied. The model is validated with a fieldwork experimental pipeline system. the mechanical vibrations from steam exhaust valves can be eliminated by careful design of the valve plug and seat. (authors)

  15. Optimization of a thermoelectric generator subsystem for high temperature PEM fuel cell exhaust heat recovery

    DEFF Research Database (Denmark)

    Gao, Xin; Andreasen, Søren Juhl; Kær, Søren Knudsen

    2014-01-01

    In previous work, a thermoelectric (TE) exhaust heat recovery subsystem for a high temperature polymer electrolyte membrane (HT-PEM) fuel cell stack was developed and modeled. Numerical simulations were conducted and have identified an optimized subsystem configuration and 4 types of compact heat...... modules are now connected into branches. The procedures of designing and optimizing this TE exhaust heat recovery subsystem are drawn out. The contribution of TE exhaust heat recovery to the HT-PEM fuel cell power system is preliminarily concluded. Its feasibility is also discussed....... exchangers with superior performance for further analysis. In this work, the on-design performances of the 4 heat exchangers are more thoroughly assessed on their corresponding optimized subsystem configurations. Afterward, their off-design performances are compared on the whole working range of the fuel...

  16. The impacts of balanced and exhaust mechanical ventilation on indoor radon

    International Nuclear Information System (INIS)

    Fisk, W.J.; Mowris, R.J.

    1987-02-01

    Models for estimating radon entry rates, indoor radon concentrations, and ventilation rates in houses with a basement or a vented crawl-space and ventilated by natural infiltration, mechanical exhaust ventilation, or balanced mechanical ventilation are described. Simulations are performed for a range of soil and housing characteristics using hourly weather data for the heating season in Spokane, WA. For a house with a basement, we show that any ventilation technique should be acceptable when the soil permeability is less than approximately 10 -12 m 2 . However, exhaust ventilation leads to substantially higher indoor radon concentrations than infiltration or balanced ventilation with the same average air exchange rate when the soil permeability is 10 -10 m 2 or greater. For houses with a crawl-space, indoor radon concentrations are lowest with balanced ventilation, intermediate with exhaust ventilation, and highest with infiltration

  17. HEAT TRANSFER IN EXHAUST SYSTEM OF A COLD START ENGINE AT LOW ENVIRONMENTAL TEMPERATURE

    Directory of Open Access Journals (Sweden)

    Snežana D Petković

    2010-01-01

    Full Text Available During the engine cold start, there is a significantly increased emission of harmful engine exhaust gases, particularly at very low environmental temperatures. Therefore, reducing of emission during that period is of great importance for the reduction of entire engine emission. This study was conducted to test the activating speed of the catalyst at low environmental temperatures. The research was conducted by use of mathematical model and developed computer programme for calculation of non-stationary heat transfer in engine exhaust system. During the research, some of constructional parameters of exhaust system were adopted and optimized at environmental temperature of 22 C. The combination of design parameters giving best results at low environmental temperatures was observed. The results showed that the temperature in the environment did not have any significant influence on pre-catalyst light-off time.

  18. Effect of EGR on the exhaust gas temperature and exhaust opacity ...

    Indian Academy of Sciences (India)

    In diesel engines, NOx formation is a highly temperature-dependent phenomenon and takes place when the temperature in the combustion chamber exceeds 2000 K. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control. One simple way of ...

  19. Flow effects due to valve and piston motion in an internal combustion engine exhaust port

    International Nuclear Information System (INIS)

    Semlitsch, Bernhard; Wang, Yue; Mihăescu, Mihai

    2015-01-01

    Highlights: • Flow regime identification depending on the valve lift during the exhaust stroke. • Analysis of the valve motion effect onto the flow development in the exhaust port. • Physical interpretation of commonly used discharge and flow coefficient formulations. • Illustration of flow effects in junction regions with pulsatile flow. - Abstract: Performance optimization regarding e.g. exhaust valve strategies in an internal combustion engine is often performed based on one-dimensional simulation investigation. Commonly, a discharge coefficient is used to describe the flow behavior in complex geometries, such as the exhaust port. This discharge coefficient for an exhaust port is obtained by laboratory experiments at fixed valve lifts, room temperatures, and low total pressure drops. The present study investigates the consequences of the valve and piston motion onto the energy losses and the discharge coefficient. Therefore, Large Eddy Simulations are performed in a realistic internal combustion geometry using three different modeling strategies, i.e. fixed valve lift and fixed piston, moving piston and fixed valve lift, and moving piston and moving valve, to estimate the energy losses. The differences in the flow field development with the different modeling approaches is delineated and the dynamic effects onto the primary quantities, e.g. discharge coefficient, are quantified. Considering the motion of piston and valves leads to negative total pressure losses during the exhaust cycle, which cannot be observed at fixed valve lifts. Additionally, the induced flow structures develop differently when valve motion is taken into consideration, which leads to a significant disparity of mass flow rates evolving through the two individual valve ports. However, accounting for piston motion and limited valve motion, leads to a minor discharge coefficient alteration of about one to two percent

  20. Automotive exhaust gas conversion: from elementary step kinetics to prediction of emission dynamics

    NARCIS (Netherlands)

    Hoebink, J.H.B.J.; Harmsen, J.M.A.; Balenovic, M.; Backx, A.C.P.M.; Schouten, J.C.

    2001-01-01

    Elementary step based kinetics show a high added value to describe the performance of catalytic exhaust gas converters under dynamic conditions, as demonstrated with a Euro test cycle. Combination of such kinetic models for individual global reactions covers the mutual interactions via common

  1. Organizational justice and individuals' withdrawal : Unlocking the influence of emotional exhaustion

    NARCIS (Netherlands)

    Cole, Michael S.; Bernerth, Jeremy B.; Walter, Frank; Holt, Daniel T.

    P>This study examined the relationships between organizational justice and withdrawal outcomes and whether emotional exhaustion was a mediator of these linkages. Data were obtained from 869 military personnel and civil servants; using structural equation modelling techniques, we examined an

  2. Effects of Teacher Personalities on Emotional Exhaustion: Mediating Role of Emotional Labor

    Science.gov (United States)

    Basim, H. Nejat; Begenirbas, Memduh; Can Yalcin, Rukiye

    2013-01-01

    One of the most indispensable and important elements of education is teachers whose personality closely affects training and education. In this context, this study examined the effects of teachers' personality traits on their emotional exhaustion in a mediating model which centers around emotional labor. Data were obtained from 798 teachers…

  3. Why is there a spike in the job finding rate at benefit exhaustion?

    NARCIS (Netherlands)

    Boone, J.; van Ours, J.C.

    2012-01-01

    Putting a limit on the duration of unemployment benefits tends to introduce a “spike” in the job finding rate shortly before benefits are exhausted. Current theories explain this spike from workers’ behavior. We present a theoretical model in which also the nature of the job matters. End-of-benefit

  4. Why is There a Spike in the Job Finding Rate at Benefit Exhaustion?

    NARCIS (Netherlands)

    Boone, J.; van Ours, J.C.

    2009-01-01

    Putting a limit on the duration of unemployment benefits tends to introduce a \\spike" in the job finding rate shortly before benefits are exhausted. Current theories explain this spike from workers' behavior. We present a theoretical model in which also the nature of the job matters. End-of-benefit

  5. Job resources and emotional exhaustion: The mediating role of learning opportunities

    NARCIS (Netherlands)

    Ruysseveldt, J. van; Verboon, P.; Smulders, P.G.W.

    2011-01-01

    The Job Demands-Resources model predicts that job demands increase and job resources decrease emotional exhaustion in employees. In this study, we investigated one possible mechanism for this, in order to provide a deeper insight into the role of job resources in this energy-depletion process. We

  6. Local Pain Dynamics during Constant Exhaustive Exercise.

    Directory of Open Access Journals (Sweden)

    Agne Slapsinskaite

    Full Text Available The purpose of this study was to delineate the topological dynamics of pain and discomfort during constant exercise performed until volitional exhaustion. Eleven physical education students were tested while cycling and running at a "hard" intensity level (e.g., corresponding to Borg's RPE (6-20 = 15. During the tests, participants reported their discomfort and pain on a body map every 15s. "Time on task" for each participant was divided into five equal non-overlapping temporal windows within which their ratings were considered for analysis. The analyses revealed that the number of body locations with perceived pain and discomfort increased throughout the five temporal windows until reaching the mean (± SE values of 4.2 ± 0.7 and 4.1 ± 0.6 in cycling and running, respectively. The dominant locations included the quadriceps and hamstrings during cycling and quadriceps and chest during running. In conclusion, pain seemed to spread throughout the body during constant cycling and running performed up to volitional exhaustion with differences between cycling and running in the upper body but not in the lower body dynamics.

  7. On the exhaust of electromagnetic drive

    Directory of Open Access Journals (Sweden)

    Patrick Grahn

    2016-06-01

    Full Text Available Recent reports about propulsion without reaction mass have been met on one hand with enthusiasm and on the other hand with some doubts. Namely, closed metal cavities, when fueled with microwaves, have delivered thrust that could eventually maintain satellites on orbits using solar power. However, the measured thrust appears to be without any apparent exhaust. Thus the Law of Action-Reaction seems to have been violated. We consider the possibility that the exhaust is in a form that has so far escaped both experimental detection and theoretical attention. In the thruster’s cavity microwaves interfere with each other and invariably some photons will also end up co-propagating with opposite phases. At the destructive interference electromagnetic fields cancel. However, the photons themselves do not vanish for nothing but continue in propagation. These photon pairs without net electromagnetic field do not reflect back from the metal walls but escape from the resonator. By this action momentum is lost from the cavity which, according to the conservation of momentum, gives rise to an equal and opposite reaction. We examine theoretical corollaries and practical concerns that follow from the paired-photon conclusion.

  8. Exhaust purification with on-board ammonia production

    Science.gov (United States)

    Robel, Wade J.; Driscoll, James J.; Coleman, Gerald N.; Knox, Kevin J.

    2009-06-30

    A power source is provided for use with selective catalytic reduction systems for exhaust-gas purification. The power source includes a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The second air-intake passage is fluidly isolated from the first air-intake passage. A fuel-supply device may be configured to supply fuel into the first exhaust passage, and a catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

  9. Exhaust constituent emission factors of printed circuit board pyrolysis processes and its exhaust control

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Hung-Lung, E-mail: hlchiang@mail.cmu.edu.tw [Department of Health Risk Management, China Medical University, Taichung, Taiwan (China); Lin, Kuo-Hsiung [Department of Environmental Engineering and Science, Fooyin University, Kaohsiung, Taiwan (China)

    2014-01-15

    Highlights: • Recycling of waste printed circuit boards is an important issue. • Pyrolysis is an emerging technology for PCB treatment. • Emission factors of VOCs are determined for PCB pyrolysis exhaust. • Iron-Al{sub 2}O{sub 3} catalyst was employed for the exhaust control. -- Abstract: The printed circuit board (PCB) is an important part of electrical and electronic equipment, and its disposal and the recovery of useful materials from waste PCBs (WPCBs) are key issues for waste electrical and electronic equipment. Waste PCB compositions and their pyrolysis characteristics were analyzed in this study. In addition, the volatile organic compound (VOC) exhaust was controlled by an iron-impregnated alumina oxide catalyst. Results indicated that carbon and oxygen were the dominant components (hundreds mg/g) of the raw materials, and other elements such as nitrogen, bromine, and copper were several decades mg/g. Exhaust constituents of CO, H{sub 2}, CH{sub 4}, CO{sub 2}, and NOx, were 60–115, 0.4–4.0, 1.1–10, 30–95, and 0–0.7 mg/g, corresponding to temperatures ranging from 200 to 500 °C. When the pyrolysis temperature was lower than 300 °C, aromatics and paraffins were the major species, contributing 90% of ozone precursor VOCs, and an increase in the pyrolysis temperature corresponded to a decrease in the fraction of aromatic emission factors. Methanol, ethylacetate, acetone, dichloromethane, tetrachloromethane and acrylonitrile were the main species of oxygenated and chlorinated VOCs. The emission factors of some brominated compounds, i.e., bromoform, bromophenol, and dibromophenol, were higher at temperatures over 400 °C. When VOC exhaust was flowed through the bed of Fe-impregnated Al{sub 2}O{sub 3}, the emission of ozone precursor VOCs could be reduced by 70–80%.

  10. An approach for estimating item sensitivity to within-person change over time: An illustration using the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog).

    Science.gov (United States)

    Dowling, N Maritza; Bolt, Daniel M; Deng, Sien

    2016-12-01

    When assessments are primarily used to measure change over time, it is important to evaluate items according to their sensitivity to change, specifically. Items that demonstrate good sensitivity to between-person differences at baseline may not show good sensitivity to change over time, and vice versa. In this study, we applied a longitudinal factor model of change to a widely used cognitive test designed to assess global cognitive status in dementia, and contrasted the relative sensitivity of items to change. Statistically nested models were estimated introducing distinct latent factors related to initial status differences between test-takers and within-person latent change across successive time points of measurement. Models were estimated using all available longitudinal item-level data from the Alzheimer's Disease Assessment Scale-Cognitive subscale, including participants representing the full-spectrum of disease status who were enrolled in the multisite Alzheimer's Disease Neuroimaging Initiative. Five of the 13 Alzheimer's Disease Assessment Scale-Cognitive items demonstrated noticeably higher loadings with respect to sensitivity to change. Attending to performance change on only these 5 items yielded a clearer picture of cognitive decline more consistent with theoretical expectations in comparison to the full 13-item scale. Items that show good psychometric properties in cross-sectional studies are not necessarily the best items at measuring change over time, such as cognitive decline. Applications of the methodological approach described and illustrated in this study can advance our understanding regarding the types of items that best detect fine-grained early pathological changes in cognition. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  11. Removing method for radon gas exhausted from nuclear fuel material

    International Nuclear Information System (INIS)

    Kato, Kenji.

    1993-01-01

    A centrifugal separator is disposed in the midway of an exhaustion pipe of a nuclear fuel handling facility, and exhausted gases are sent into a rotational cylinder of the separator. Radon gases in the midway of exhaustion are separated from the exhaustion gases by the centrifugal force of the separator and caused to stagnate at the periphery of the circumferential wall of the rotational cylinder. At the same time, the exhaustion gases having the radon gases separated therefrom are exhausted from the periphery of a rotational shaft of the rotational cylinder. Then, the radon gases stagnated in the rotational cylinder are decayed depending on the half-decay time. With such procedures, the radon gases can be removed continuously without discharging them to the outside. Further, it is preferred that an exhaustion blower or the like for putting the inside of the nuclear fuel handing facility to a negative pressure is disposed as in a conventional case. Further, a plurality of centrifugal separators may be disposed to exhaustion pipes, to remove radon gases in the exhaust gases by a multi stage way. Radon gases can be removed in a saved space with no requirement for exchange of adsorbents or temperature control. (T.M.)

  12. Ion-ion Recombination and Chemiion Concentrations In Aircraft Exhaust

    Science.gov (United States)

    Turco, R. P.; Yu, F.

    Jet aircraft emit large quantities of ultrafine volatile aerosols, as well as soot parti- cles, into the environment. To determine the long-term effects of these emissions, a better understanding of the mechanisms that control particle formation and evolution is needed, including the number and size dispersion. A recent explanation for aerosol nucleation in a jet wake involves the condensation of sulfuric acid vapor, and cer- tain organic compounds, onto charged molecular clusters (chemiions) generated in the engine combustors (Yu and Turco, 1997). Massive charged aggregates, along with sulfuric acid and organic precursor vapors, have been detected in jet plumes under cruise conditions. In developing the chemiion nucleation theory, Yu and Turco noted that ion-ion recombination in the engine train and jet core should limit the chemiion emission index to 1017/kg-fuel. This value is consistent with ion-ion recombination coefficients of 1×10-7 cm3/s over time scales of 10-2 s. However, the evolution of the ions through the engine has not been adequately studied. The conditions at the combustor exit are extreme-temperatures approach 1500 K, and pressures can reach 30 atmospheres. In this presentation, we show that as the combustion gases expand and cool, two- and three-body ion-ion recombination processes control the chemiion concentration. The concepts of mutual neutralization and Thomson recombination are first summarized, and appropriate temperature and pressure dependent recombination rate coefficients are derived for the aircraft problem. A model for ion losses in jet exhaust is then formulated using an "invariance" principle discussed by Turco and Yu (1997) in the context of a coagulating aerosol in an expanding plume. This recombina- tion model is applied to estimate chemiion emission indices for a range of operational engine conditions. The predicted ion emission rates are found to be consistent with observations. We discuss the sources of variance in chemiion

  13. Study on acoustical properties of sintered bronze porous material for transient exhaust noise of pneumatic system

    Science.gov (United States)

    Li, Jingxiang; Zhao, Shengdun; Ishihara, Kunihiko

    2013-05-01

    A novel approach is presented to study the acoustical properties of sintered bronze material, especially used to suppress the transient noise generated by the pneumatic exhaust of pneumatic friction clutch and brake (PFC/B) systems. The transient exhaust noise is impulsive and harmful due to the large sound pressure level (SPL) that has high-frequency. In this paper, the exhaust noise is related to the transient impulsive exhaust, which is described by a one-dimensional aerodynamic model combining with a pressure drop expression of the Ergun equation. A relation of flow parameters and sound source is set up. Additionally, the piston acoustic source approximation of sintered bronze silencer with cylindrical geometry is presented to predict SPL spectrum at a far-field observation point. A semi-phenomenological model is introduced to analyze the sound propagation and reduction in the sintered bronze materials assumed as an equivalent fluid with rigid frame. Experiment results under different initial cylinder pressures are shown to corroborate the validity of the proposed aerodynamic model. In addition, the calculated sound pressures according to the equivalent sound source are compared with the measured noise signals both in time-domain and frequency-domain. Influences of porosity of the sintered bronze material are also discussed.

  14. Ice-nucleating particle emissions from photochemically aged diesel and biodiesel exhaust

    Science.gov (United States)

    Schill, G. P.; Jathar, S. H.; Kodros, J. K.; Levin, E. J. T.; Galang, A. M.; Friedman, B.; Link, M. F.; Farmer, D. K.; Pierce, J. R.; Kreidenweis, S. M.; DeMott, P. J.

    2016-05-01

    Immersion-mode ice-nucleating particle (INP) concentrations from an off-road diesel engine were measured using a continuous-flow diffusion chamber at -30°C. Both petrodiesel and biodiesel were utilized, and the exhaust was aged up to 1.5 photochemically equivalent days using an oxidative flow reactor. We found that aged and unaged diesel exhaust of both fuels is not likely to contribute to atmospheric INP concentrations at mixed-phase cloud conditions. To explore this further, a new limit-of-detection parameterization for ice nucleation on diesel exhaust was developed. Using a global-chemical transport model, potential black carbon INP (INPBC) concentrations were determined using a current literature INPBC parameterization and the limit-of-detection parameterization. Model outputs indicate that the current literature parameterization likely overemphasizes INPBC concentrations, especially in the Northern Hemisphere. These results highlight the need to integrate new INPBC parameterizations into global climate models as generalized INPBC parameterizations are not valid for diesel exhaust.

  15. Flow effects due to pulsation in an internal combustion engine exhaust port

    International Nuclear Information System (INIS)

    Semlitsch, Bernhard; Wang, Yue; Mihăescu, Mihai

    2014-01-01

    Highlights: • Using POD analysis to identify large coherent flow structures in a complex geometry. • Flow field alters significant for constant and pulsating boundary conditions. • The discharge coefficient of the exhaust port decreases 2% with flow pulsation. • Pulsation causes a pumping mechanism due to a phase shift of pressure and momentum. - Abstract: In an internal combustion engine, the residual energy remaining after combustion in the exhaust gasses can be partially recovered by a downstream arranged device. The exhaust port represents the passage guiding the exhaust gasses from the combustion chamber to the energy recovering device, e.g. a turbocharger. Thus, energy losses in the course of transmission shall be reduced as much as possible. However, in one-dimensional engine models used for engine design, the exhaust port is reduced to its discharge coefficient, which is commonly measured under constant inflow conditions neglecting engine-like flow pulsation. In this present study, the influence of different boundary conditions on the energy losses and flow development during the exhaust stroke are analyzed numerically regarding two cases, i.e. using simple constant and pulsating boundary conditions. The compressible flow in an exhaust port geometry of a truck engine is investigated using three-dimensional Large Eddy Simulations (LES). The results contrast the importance of applying engine-like boundary conditions in order to estimate accurately the flow induced losses and the discharge coefficient of the exhaust port. The instantaneous flow field alters significantly when pulsating boundary conditions are applied. Thus, the induced losses by the unsteady flow motion and the secondary flow motion are increased with inflow pulsations. The discharge coefficient decreased about 2% with flow pulsation. A modal flow decomposition method, i.e. Proper Orthogonal Decomposition (POD), is used to analyze the coherent structures induced with the particular

  16. Pitot survey of exhaust flow field of a 2-D scramjet nozzle at Mach 6 with air or freon and argon used for exhaust simulation

    Science.gov (United States)

    Monta, William J.

    1992-01-01

    A pitot-rake survey of the simulated exhaust of a half-span scramjet nozzle model was conducted in the Langley 20-Inch Mach 6 Tunnel to provide an additional data set for computational fluid dynamics (CFD) code comparisons. A wind-tunnel model was tested with a 26-tube pitot rake that could be manually positioned along the mid-semispan plane of the model. The model configuration had an external expansion surface of 20 degrees and an internal cowl expansion of 12 degrees; tests were also performed with a flow fence. Tests were conducted at a free-stream Reynolds number of approximately 6.5 x 10(exp 6) per foot and a model angle of attack of -0.75 degrees. The two exhaust gas mediums that were tested were air and a Freon 12-argon mixture. Each medium was tested at two jet total pressures at approximately 28 and 14 psia. This document presents the flow-field survey results in graphical as well as tabular form, and several observations concerning the results are discussed. The surveys reveal the major expected flow-field characteristics for each test configuration. For a 50-percent freon 12 and 50-percent argon mixture by volume (Fr-Ar), the exhaust jet pressures were slightly higher than those for air. The addition of a flow fence slightly raised the pitot pressure for the Fr-Ar mixture, but it produced little change for air. For the Fr-Ar exhaust, the plume was larger and the region between the shock wave and plume was smaller.

  17. The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly

    Science.gov (United States)

    2000-01-01

    The X-40 sub-scale technology demonstrator and its U.S. Army CH-47 Chinook helicopter mothership fly over a dry lakebed runway during a captive-carry test flight from NASA's Dryden Flight Research Center, Edwards, California. The X-40 is attached to a sling which is suspended from the CH-47 by a 110-foot-long cable during the tests, while a small parachute trails behind to provide stability. The captive carry flights are designed to verify the X-40's navigation and control systems, rigging angles for its sling, and stability and control of the helicopter while carrying the X-40 on a tether. Following a series of captive-carry flights, the X-40 made free flights from a launch altitude of about 15,000 feet above ground, gliding to a fully autonomous landing. The X-40 is an unpowered 82 percent scale version of the X-37, a Boeing-developed spaceplane designed to demonstrate various advanced technologies for development of future lower-cost access to space vehicles. The X-37 will be carried into space aboard a space shuttle and then released to perform various maneuvers and a controlled re-entry through the Earth's atmosphere to an airplane-style landing on a runway, controlled entirely by pre-programmed computer software.

  18. Chilean experimental version of the State-Trait Depression Questionnaire (ST-DEP: Trait sub-scale (T-DEP

    Directory of Open Access Journals (Sweden)

    Pablo Vera-Villarroel

    2008-01-01

    Full Text Available This instrumental study presents the first validity and reliability data for the Trait subscale (T-DEP of the Chilean experimental version of the State and Trait Depression Inventory (ST-DEP: Euthymia and Dysthymia. The data were obtained from a sample of 300 university students. The internal consistency values for the TDEP were high (.90. The test-retest values from eight weeks time interval (fifty six days were elevated (.78. A factorial analysis of the principal components revealed a principal factor for all of the constructed items in this experimental version of the TDEP. The last, promax rotation showed two clear main factors similar in size: negative affectivity (Dysthymia and positive affectivity (Euthymia. The convergent validity indexes for the Beck Depression Inventory and the Zung Self Rating Depression Scale, were also high, with indexes ranging from .64 to .71. The correlation between State- Trait Anxiety Inventory and the depression scales used in this study was high (between .63 and .78, once again indicating the usual overlapping between anxiety and depression seen in most depression inventories.

  19. Comparative Responsiveness of the PROMIS Pain Interference Short Forms, Brief Pain Inventory, PEG, and SF-36 Bodily Pain Subscale.

    Science.gov (United States)

    Kean, Jacob; Monahan, Patrick O; Kroenke, Kurt; Wu, Jingwei; Yu, Zhangsheng; Stump, Tim E; Krebs, Erin E

    2016-04-01

    To compare the sensitivity to change and the responsiveness to intervention of the PROMIS Pain Interference short forms, Brief Pain Inventory (BPI), 3-item PEG scale, and SF-36 Bodily Pain subscale in a sample of patients with persistent musculoskeletal pain of moderate severity. Standardized response means, standardized effect sizes, and receiver operating curve analyses were used to assess change between baseline and 3-month assessments in 250 participants who participated in a randomized clinical effectiveness trial of collaborative telecare management for moderate to severe and persistent musculoskeletal pain. The BPI, PEG, and SF-36 Bodily Pain measures were more sensitive to patient-reported global change than the PROMIS Pain Interference short forms, especially for the clinically improved group, for which the change detected by the PROMIS short forms was not statistically significant. The BPI was more responsive to the clinical intervention than the SF-36 Bodily Pain and PROMIS Pain Interference measures. Post hoc analyses exploring these findings did not suggest that differences in content or rating scale structure (number of response options or anchoring language) adequately explained the observed differences in the detection of change. In this clinical trial, the BPI and PEG measures were better able to detect change than the SF-36 Bodily Pain and PROMIS Pain Interference measures.

  20. A GM (1, 1 Markov Chain-Based Aeroengine Performance Degradation Forecast Approach Using Exhaust Gas Temperature

    Directory of Open Access Journals (Sweden)

    Ning-bo Zhao

    2014-01-01

    Full Text Available Performance degradation forecast technology for quantitatively assessing degradation states of aeroengine using exhaust gas temperature is an important technology in the aeroengine health management. In this paper, a GM (1, 1 Markov chain-based approach is introduced to forecast exhaust gas temperature by taking the advantages of GM (1, 1 model in time series and the advantages of Markov chain model in dealing with highly nonlinear and stochastic data caused by uncertain factors. In this approach, firstly, the GM (1, 1 model is used to forecast the trend by using limited data samples. Then, Markov chain model is integrated into GM (1, 1 model in order to enhance the forecast performance, which can solve the influence of random fluctuation data on forecasting accuracy and achieving an accurate estimate of the nonlinear forecast. As an example, the historical monitoring data of exhaust gas temperature from CFM56 aeroengine of China Southern is used to verify the forecast performance of the GM (1, 1 Markov chain model. The results show that the GM (1, 1 Markov chain model is able to forecast exhaust gas temperature accurately, which can effectively reflect the random fluctuation characteristics of exhaust gas temperature changes over time.

  1. GASOLINE VEHICLE EXHAUST PARTICLE SAMPLING STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Kittelson, D; Watts, W; Johnson, J; Zarling, D Schauer,J Kasper, K; Baltensperger, U; Burtscher, H

    2003-08-24

    The University of Minnesota collaborated with the Paul Scherrer Institute, the University of Wisconsin (UWI) and Ricardo, Inc to physically and chemically characterize the exhaust plume from recruited gasoline spark ignition (SI) vehicles. The project objectives were: (1) Measure representative particle size distributions from a set of on-road SI vehicles and compare these data to similar data collected on a small subset of light-duty gasoline vehicles tested on a chassis dynamometer with a dilution tunnel using the Unified Drive Cycle, at both room temperature (cold start) and 0 C (cold-cold start). (2) Compare data collected from SI vehicles to similar data collected from Diesel engines during the Coordinating Research Council E-43 project. (3) Characterize on-road aerosol during mixed midweek traffic and Sunday midday periods and determine fleet-specific emission rates. (4) Characterize bulk- and size-segregated chemical composition of the particulate matter (PM) emitted in the exhaust from the gasoline vehicles. Particle number concentrations and size distributions are strongly influenced by dilution and sampling conditions. Laboratory methods were evaluated to dilute SI exhaust in a way that would produce size distributions that were similar to those measured during laboratory experiments. Size fractionated samples were collected for chemical analysis using a nano-microorifice uniform deposit impactor (nano-MOUDI). In addition, bulk samples were collected and analyzed. A mixture of low, mid and high mileage vehicles were recruited for testing during the study. Under steady highway cruise conditions a significant particle signature above background was not measured, but during hard accelerations number size distributions for the test fleet were similar to modern heavy-duty Diesel vehicles. Number emissions were much higher at high speed and during cold-cold starts. Fuel specific number emissions range from 1012 to 3 x 1016 particles/kg fuel. A simple

  2. Study of recycling exhaust gas energy of hybrid pneumatic power system with CFD

    International Nuclear Information System (INIS)

    Huang, K. David; Quang, Khong Vu; Tseng, K.-T.

    2009-01-01

    A hybrid pneumatic power system (HPPS) is integrated by an internal combustion engine (ICE), a high efficiency turbine, an air compressor and an energy merger pipe, which can not only recycle and store exhaust gas energy but also convert it into useful mechanical energy. Moreover, it can make the ICE operate in its optimal state of maximum efficiency; and thus, it can be considered an effective solution to improve greatly the exhaust emissions and increase the overall energy efficiency of the HPPS. However, in this system, the flow energy merger of both high pressure compressed air flow and high temperature exhaust gas flow of the ICE greatly depends on the merging capability of the energy merger pipe. If the compressed air pressure (P air ) at the air inlet is too high, smooth transmission and mixture of the exhaust gas flow are prevented, which will interfere with the operation condition of the ICE. This shortcoming is mostly omitted in the previous studies. The purpose of this paper is to study the effect of the level of P air and the contraction of cross-section area (CSA) at the merging position on the flow energy merger and determine their optimum adjustments for a better merging process by using computation fluid dynamics (CFD). In addition, the CFD model was validated on the basis of the experimental data, including the temperature and static pressure of the merger flow at the outlet of the energy merger pipe. It was found that the simulation results were in good agreement with the experimental data. The simulation results show that exhaust gas recycling efficiency and merger flow energy are significantly dependent on the optimum adjustment of the CSA for changes in P air . Under these optimum adjustments, the exhaust gas recycling efficiency can reach about 83%. These results will be valuable bases to research and design the energy merger pipe of the HPPS.

  3. Astrocytic glycogen-derived lactate fuels the brain during exhaustive exercise to maintain endurance capacity.

    Science.gov (United States)

    Matsui, Takashi; Omuro, Hideki; Liu, Yu-Fan; Soya, Mariko; Shima, Takeru; McEwen, Bruce S; Soya, Hideaki

    2017-06-13

    Brain glycogen stored in astrocytes provides lactate as an energy source to neurons through monocarboxylate transporters (MCTs) to maintain neuronal functions such as hippocampus-regulated memory formation. Although prolonged exhaustive exercise decreases brain glycogen, the role of this decrease and lactate transport in the exercising brain remains less clear. Because muscle glycogen fuels exercising muscles, we hypothesized that astrocytic glycogen plays an energetic role in the prolonged-exercising brain to maintain endurance capacity through lactate transport. To test this hypothesis, we used a rat model of exhaustive exercise and capillary electrophoresis-mass spectrometry-based metabolomics to observe comprehensive energetics of the brain (cortex and hippocampus) and muscle (plantaris). At exhaustion, muscle glycogen was depleted but brain glycogen was only decreased. The levels of MCT2, which takes up lactate in neurons, increased in the brain, as did muscle MCTs. Metabolomics revealed that brain, but not muscle, ATP was maintained with lactate and other glycogenolytic/glycolytic sources. Intracerebroventricular injection of the glycogen phosphorylase inhibitor 1,4-dideoxy-1,4-imino-d-arabinitol did not affect peripheral glycemic conditions but suppressed brain lactate production and decreased hippocampal ATP levels at exhaustion. An MCT2 inhibitor, α-cyano-4-hydroxy-cinnamate, triggered a similar response that resulted in lower endurance capacity. These findings provide direct evidence for the energetic role of astrocytic glycogen-derived lactate in the exhaustive-exercising brain, implicating the significance of brain glycogen level in endurance capacity. Glycogen-maintained ATP in the brain is a possible defense mechanism for neurons in the exhausted brain.

  4. Exhaust catalysis studies using in-situ positron emission

    International Nuclear Information System (INIS)

    Vonkeman, K.A.

    1990-01-01

    In this thesis the kinetics of noble metal catalysts with a formulation related to that of commercial automotive exhaust catalysts, have been examined. The application of a new radioisotope tracer technique in studies of catalyst kinetics is described. Reactant and product molecules were pulsed over a catalyst under conditions such, that the reaction rates were kinetically controlled. Labelling of the reacting molecules enables the in-situ measurement of transient phenomena in a reactor as a function of time and position, if a tomograph is used as detection system. Integral reactor profiles are measured, by which concentration gradients occurring in the reactor can be studied. The large amount of data obtained during each experiment were used to quantify the kinetics. To this end, a refined mathematical model of the kinetics based on the elementary steps of adsorption, desorption and surface reaction was used to simulate the experiments. The experimental conditions in this study were representative for the cold start of a car, when the catalyst is heating up. By applying small catalyst particles and high linear velocities the influence of transport phenomena was excluded so that the experiments were carried out in the kinetically controlled regime. Reaction kinetics of carbon monoxide oxidation by oxygen and nitrogen oxide were studied. Experimental data obtained with surface science techniques were very useful in constructing the kinetic model. By simulating the experiments, the relevant kinetic parameters could be quantified and information on the elementary reaction steps was obtained. Since carbon dioxide adsorbs strongly to the catalyst carrier; 10% carbon dioxide was added to the gas phase (in actual automotive exhaust gas the concentration of carbon dioxide is 10 - 15%). This enabled the determination of the transients due to the interaction of gas components with the catalytically active compounds of the catalyst. (author). 446 refs.; 57 figs.; 21 tabs

  5. Improvement of the thermal and mechanical flow characteristics in the exhaust system of piston engine through the use of ejection effect

    Science.gov (United States)

    Plotnikov, L. V.; Zhilkin, B. P.; Brodov, Yu M.

    2017-11-01

    The results of experimental research of gas dynamics and heat transfer in the exhaust process in piston internal combustion engines are presented. Studies were conducted on full-scale models of piston engine in the conditions of unsteady gas-dynamic (pulsating flows). Dependences of the instantaneous flow speed and the local heat transfer coefficient from the crankshaft rotation angle in the exhaust pipe are presented in the article. Also, the flow characteristics of the exhaust gases through the exhaust systems of various configurations are analyzed. It is shown that installation of the ejector in the exhaust system lead to a stabilization of the flow and allows to improve cleaning of the cylinder from exhaust gases and to optimize the thermal state of the exhaust pipes. Experimental studies were complemented by numerical simulation of the working process of the DM-21 diesel engine (production of “Ural diesel-motor plant”). The object of modeling was the eight-cylinder diesel with turbocharger. The simulation was performed taking into account the processes nonstationarity in the intake and exhaust pipes for the various configurations of exhaust systems (with and without ejector). Numerical simulation of the working process of diesel was performed in ACTUS software (ABB Turbo Systems). The simulation results confirmed the stabilization of the flow due to the use of the ejection effect in the exhaust system of a diesel engine. The use of ejection in the exhaust system of the DM-21 diesel leads to improvement of cleaning cylinders up to 10 %, reduces the specific fuel consumption on average by 1 %.

  6. Vital Exhaustion and Coronary Heart Disease Risk

    DEFF Research Database (Denmark)

    Frestad, Daria; Prescott, Eva

    2017-01-01

    INFO (1980 to July 2015; articles in English and published articles only), and bibliographies. Information on aim, study design, sample size, inclusion and exclusion criteria, assessment methods of psychological risk factors, and results of crude and adjusted regression analyses were abstracted independently......OBJECTIVES: The construct of vital exhaustion has been identified as a potential independent psychological risk factor for incident and recurrent coronary heart disease (CHD). Despite several decades of research, no systematic review or meta-analysis has previously attempted to collate.......22-1.85) for prospective studies, and 2.61 (95% CI = 1.66-4.10) for case-control studies using hospital controls. Risk of recurrent events in patients with CHD was 2.03 (95% CI = 1.54-2.68). The pooled adjusted risk of chronic heart failure in healthy populations was 1.37 (95% CI = 1.21-1.56), but this was based...

  7. Inerting Aircraft Fuel Systems Using Exhaust Gases

    Science.gov (United States)

    Hehemann, David G.

    2002-01-01

    Our purpose in this proposal was to determine the feasibility of using carbon dioxide, possibly obtained from aircraft exhaust gases as a substance to inert the fuel contained in fuel tanks aboard aircraft. To do this, we decided to look at the effects carbon dioxide has upon commercial Jet-A aircraft fuel. In particular, we looked at the solubility of CO2 in Jet-A fuel, the pumpability of CO2-saturated Jet-A fuel, the flashpoint of Jet-A fuel under various mixtures of air and CO2, the static outgassing of CO2-Saturated Jet-A fuel and the dynamic outgassing of Jet-A fuel during pumping of Jet-A fuel.

  8. Research on the Efficiency of Side Exhausters

    Directory of Open Access Journals (Sweden)

    Ina Tetsman

    2011-02-01

    Full Text Available The article focuses on the relevant technology of environmental protection which includes an effective collection, disposal and control of aerosol and gases contaminants removed from the evaporating surfaces of electroplating tanks. The task of the paper is to help with finding the new ways of collecting and disposing aerosol pollution and to reduce the quantity of equipment and service costs. The article also discusses pollution formation and sorts and performance of side draft and slot hoods for vapour capture. Besides, the paper deals with the formation of vapour over the tank and the features of benefit that depend on absorber‘s shape. Exhaust velocity and its dependencies are analyzed.Article in Lithuanian

  9. Reduction method of exhaust gas quantity

    Energy Technology Data Exchange (ETDEWEB)

    Ono, Y.; Morishita, K.

    1975-02-08

    A cleaning method for automobile exhaust through contact with sintered oxide semiconductors consisting of tin, antimony, manganese, and palladium oxides is discussed. This device has a much higher efficiency and lasts longer than any similar device developed previously consisting of oxides of iron, manganese cobalt, nickel, aluminum, and other rare earth metals. This sintered oxide semiconductor device is composed of: tin oxide: 30 wt ratio, tin hydrogen oxide: 30 wt ratio, antimony oxide: 2 wt ratio, manganese chloride: 2 wt ratio, palladium chloride: 1 wt ratio, carbon powder: 4 wt ratio, and ammonium carbonate: 10 wt ratio, for example. This device converts 100 percent of carbon monoxide into carbon dioxide at 350 C. This compound provides oxygen to CO at higher temperatures and absorbs oxygen from air at normal temperatures. There is no effect on efficiency.

  10. Neural activation in stress-related exhaustion

    DEFF Research Database (Denmark)

    Gavelin, Hanna Malmberg; Neely, Anna Stigsdotter; Andersson, Micael

    2017-01-01

    The primary purpose of this study was to investigate the association between burnout and neural activation during working memory processing in patients with stress-related exhaustion. Additionally, we investigated the neural effects of cognitive training as part of stress rehabilitation. Fifty...... association between burnout level and working memory performance was found, however, our findings indicate that frontostriatal neural responses related to working memory were modulated by burnout severity. We suggest that patients with high levels of burnout need to recruit additional cognitive resources...... to uphold task performance. Following cognitive training, increased neural activation was observed during 3-back in working memory-related regions, including the striatum, however, low sample size limits any firm conclusions....

  11. Nurses' exhaustion: the role of flow at work between job demands and job resources.

    Science.gov (United States)

    Zito, Margherita; Cortese, Claudio G; Colombo, Lara

    2016-01-01

    In the light of the job demands-resources model, this study aimed to detect the mediating role of flow at work between job demands and job resources on one side, and exhaustion on the other. In a historical period where it is necessary to reduce the abandonment of nursing profession, flow is a useful tool to investigate the factors that can promote work motivation and prevent psychological distress. A cross-sectional study was conducted in a hospital, and 279 nurses completed a questionnaire. Analyses conducted are descriptive statistics, alphas, correlations and a structural equations model that considers the mediating role of flow at work. Findings show both the central role of job resources in determining flow at work, and the mediating role of flow at work in decreasing exhaustion, starting from job resources, and in decreasing the effect of job demands on exhaustion. Moreover, flow at work directly decreases exhaustion. Results show the relevance of containing job demands and provide job resources to promote positive experiences at work. To promote flow at work, organizations should offer specific resources, such as supervisors' support, job autonomy, and psychological support to manage the emotional charge. © 2015 John Wiley & Sons Ltd.

  12. The Effect of Condensing Steam Turbine Exhaust Hood Body Geometry on Exhaust Performance Efficiency

    Science.gov (United States)

    Gribin, V. G.; Paramonov, A. N.; Mitrokhova, O. M.

    2018-06-01

    The article presents data from combined numerical and experimental investigations of the effect that the overall dimensions of the exhaust hood of a steam turbine with an underslung condenser has on the aerodynamic losses in the hood. Owing to the properly selected minimum permissible overall dimensions of the exhaust hood, more efficient operation of this turbine component is achieved, better vibration stability of the turbine set shaft line is obtained, and lower costs are required for arranging the steam turbine plant in the turbine building. Experiments have shown that the main overall dimensions of the hood body have a determining effect on the exhaust hood flow path profile and on its aerodynamic performance. Owing to properly selected ratios between the exhaust hood body main sizes without a diffuser, a total loss coefficient equal to approximately unity has been obtained. By using an axial-radial diffuser, the energy loss can be decreased by 30-40% depending on the geometrical parameters and level of velocities in the inlet section of a hood having the optimal overall dimensions. By using the obtained results, it becomes possible to evaluate the overall dimensions necessary for achieving the maximal aerodynamic hood efficiency and, as a consequence, to obtain better technical and economic indicators of the turbine plant as a whole already at the initial stage of its designing. If a need arises to select overall dimensions smaller than their optimal values, the increase of energy loss can be estimated using the presented dependences. The cycle of investigations was carried out on the experimental setups available in the fundamental research laboratory of the Moscow Power Engineering Institute National University's Department of Steam and Gas Turbines with due regard to the operating parameters and similarity criteria.

  13. Coupled simulation of a system for the utilization of exhaust heat and cooling of the interior of commercial vehicles; Gekoppelte Simulation eines Abgaswaermenutzungs- und Fahrzeugkuehlsystems im Nutzfahrzeug

    Energy Technology Data Exchange (ETDEWEB)

    Ambros, Peter; Fezer, Axel; Kapitel, Julian [TheSys GmbH, Kirchentellinsfurt (Germany)

    2012-11-01

    Based on a simulation software called GT-Suite by Gamma Technology, a one-dimensional model of a waste-heat recovery system with utility vehicle boundary conditions was developed. Using this model, it is possible to simulate stationary operating points of this type WHR. A Clausius-Rankine cycle is used in the power-heat cogeneration. The Clausius-Rankine cycle is linked to the exhaust system by two boilers. The first boiler is installed in the main exhaust steam, the second boiler is implemented in the exhaust gas recirculation. Besides the waste-heat recovery system, the integrated cooling system of the vehicle is also modeled. (orig.)

  14. Unemployment Benefit Exhaustion: Incentive Effects on Job-Finding Rates

    Science.gov (United States)

    Filges, Trine; Geerdsen, Lars Pico; Knudsen, Anne-Sofie Due; Jørgensen, Anne-Marie Klint

    2015-01-01

    Purpose: This systematic review studied the impact of exhaustion of unemployment benefits on the exit rate out of unemployment and into employment prior to benefit exhaustion or shortly thereafter. Method: We followed Campbell Collaboration guidelines to prepare this review, and ultimately located 12 studies for final analysis and interpretation.…

  15. 46 CFR 63.25-7 - Exhaust gas boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas boilers. (a) Construction...

  16. Perceived social support and emotional exhaustion in HIV/AIDS ...

    African Journals Online (AJOL)

    Counsellors have been identified as a group of professionals at elevated risk of burnout in general and emotional exhaustion in particular. Considering the nature of the illness, ... the quality of the services they provide. Key words: Emotional exhaustion, perceived social support, burnout syndrome, demographic variables.

  17. 49 CFR 229.43 - Exhaust and battery gases.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Exhaust and battery gases. 229.43 Section 229.43... § 229.43 Exhaust and battery gases. (a) Products of combustion shall be released entirely outside the... conditions. (b) Battery containers shall be vented and batteries kept from gassing excessively. ...

  18. 30 CFR 36.25 - Engine exhaust system.

    Science.gov (United States)

    2010-07-01

    ... (see § 36.23(b)(2)). (3) In lieu of a space-place flame arrester, an exhaust-gas cooling box or... exhaust system for convenient, temporary attachment of a pressure gage at a point suitable for measuring the total back pressure in the system. The connection also shall be suitable for temporary attachment...

  19. Diesel Engine Exhaust: Basis for Occupational Exposure Limit Value.

    Science.gov (United States)

    Taxell, Piia; Santonen, Tiina

    2017-08-01

    Diesel engines are widely used in transport and power supply, making occupational exposure to diesel exhaust common. Both human and animal studies associate exposure to diesel exhaust with inflammatory lung effects, cardiovascular effects, and an increased risk of lung cancer. The International Agency for Research on Cancer has evaluated diesel exhaust as carcinogenic to humans. Yet national or regional limit values for controlling occupational exposure to diesel exhaust are rare. In recent decades, stricter emission regulations have led to diesel technologies evolving significantly, resulting in changes in exhaust emissions and composition. These changes are also expected to influence the health effects of diesel exhaust. This review provides an overview of the current knowledge on the health effects of diesel exhaust and the influence of new diesel technologies on the health risk. It discusses the relevant exposure indicators and perspectives for setting occupational exposure limit values for diesel exhaust, and outlines directions for future research. The review is based on a collaborative evaluation report by the Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals and the Dutch Expert Committee on Occupational Safety. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Experimental studies of impact of exhaust gas recirculation on the ...

    African Journals Online (AJOL)

    This paper considers the problem of reducing the nitrogen oxides emissions in exhaust gases (EG) of diesel engine by exhaust gas recirculation (EGR). Based on the carried out study the influence of EGR on technical-and-economic and environmental performance of a diesel engine was found as well as main directions of ...

  1. 40 CFR 1065.230 - Raw exhaust flow meter.

    Science.gov (United States)

    2010-07-01

    ... the following cases, you may use a raw exhaust flow meter signal that does not give the actual value... dew and pressure, p total at the flow meter inlet. Use these values in emission calculations according... CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.230 Raw exhaust...

  2. 40 CFR 86.1342-90 - Calculations; exhaust emissions.

    Science.gov (United States)

    2010-07-01

    ... exhaust sample in sampling solution, µg/ml. (vii) VAE = Volume of sampling solution for dilute exhaust... sampling solution, µg/ml. (xiii) VAA = Volume of sampling solution for dilution air formaldehyde sample, ml... paragraph (d)(3) of this section): Wet concentration = Kw × dry concentration. Where: (1)(i) For English...

  3. 30 CFR 36.26 - Composition of exhaust gas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Composition of exhaust gas. 36.26 Section 36.26... EQUIPMENT Construction and Design Requirements § 36.26 Composition of exhaust gas. (a) Preliminary engine... methane) is a satisfactory substitute for pure methane in these tests. (c) Coupling or adapter. The...

  4. Effect of diesel generator exhaust pollutants on growth of Vinca ...

    African Journals Online (AJOL)

    The effects of exhaust pollutants of generator on root and shoot length, root and shoot weight, number of leaflets and leaf area, leaf and total plant dry weight of Vinca rosea and Ruellia tuberosa were studied. The treatment of exhaust pollutants produced significant effects on root, shoot growth, number of leaflet and leaf ...

  5. Emotional exhaustion may trigger cut in working hours

    NARCIS (Netherlands)

    Koppes, L.

    2012-01-01

    Researchers in the Netherlands have been examining to what extent workers are modifying their hours to cope with high levels of work-related emotional exhaustion. Findings reveal that most full-time employees would prefer a cut in their hours, with those reporting emotional exhaustion wanting a

  6. 40 CFR 86.211-94 - Exhaust gas analytical system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Exhaust gas analytical system. 86.211-94 Section 86.211-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.211-94 Exhaust gas...

  7. FY 2000 report on the results of the project for measures for rationalization of the international energy utilization - the model project for the heightening of efficiency of the international energy consumption. 1/2. Model project for facilities for effective utilization of by-producing exhaust gases from chemical plant, etc.; 2000 nendo kokusai energy shohi koritsuka tou moderu jigyo seika hokokusho. Kagaku kojo fukusei haigasu tou yuko riyo setsubi moderu jigyo (1/2)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    For the purpose of contributing to the reduction in the energy consumption in China and the stable energy supply in Japan by heightening efficiency of the energy utilization in the petrochemical industry which is an industry of much energy consumption in China, a model project for facilities for effective utilization of by-producing gases from chemical plant, etc. was carried out, and the FY 2000 results were reported. Concretely, the combustion incinerator and combustion exhaust gas recovery facilities for waste water and gas were to be installed at acrylonitrile plant of petrochemical plant in China to recover the combustion exhaust gas as process gas used in plant for effective utilization. The plant at installation site has been run since 1995, having a production capacity of 50,000-60,000 tons. In this fiscal year, the detailed design and supply of electric instrumentation equipment and manufacture of boiler facilities were carried out according to the basic design made in the previous fiscal year. Further, the equipment manufactured in the previous year and this fiscal year were transported and inspected. The paper also reviewed drawings of the design of the facilities for part of which China takes responsibility. (NEDO)

  8. FY 2000 report on the results of the project for measures for rationalization of the international energy utilization - the model project for the heightening of efficiency of the international energy consumption. 2/2. Model project for facilities for effective utilization of by-producing exhaust gases from chemical plant, etc.; 2000 nendo kokusai energy shohi koritsuka tou moderu jigyo seika hokokusho. Kagaku kojo fukusei haigasu tou yuko riyo setsubi moderu jigyo (2/2)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    For the purpose of contributing to the reduction in the energy consumption in China and the stable energy supply in Japan by heightening efficiency of the energy utilization in the petrochemical industry which is an industry of much energy consumption in China, a model project for facilities for effective utilization of by-producing gases from chemical plant, etc. was carried out, and the FY 2000 results were reported. Concretely, the combustion incinerator and combustion exhaust gas recovery facilities for waste water and gas were to be installed at acrylonitrile plant of petrochemical plant in China to recover the combustion exhaust gas as process gas used in plant for effective utilization. In this fiscal year, the detailed design and supply of electric instrumentation equipment and manufacture of boiler facilities were carried out according to the basic design made in the previous fiscal year. Further, the equipment manufactured in the previous year and this fiscal year were transported and inspected. The paper also reviewed drawings of the design of the facilities for part of which China takes responsibility. The separate volume (2/2) included drawings of valve, fire detector, orifice, thermocouple, motor control equipment, etc. (NEDO)

  9. Holdup measurements of plutonium in glove box exhausts

    International Nuclear Information System (INIS)

    Glick, J.B.; Haas, F.X.; McKamy, J.N.; Garrett, A.G.

    1991-01-01

    A new measurement technique has been developed to quantify plutonium in process glove box exhausts. The technique implemented at Rocky Flats Plant utiltizes a shielded, collimated 0.5in. x 0.5in. bismuth germanate (BGO) gamma-ray detector. Pairs of measurements are made at one foot intervals along the duct. One measurement is made with the detector viewing the bottom of the duct with the detector crystal approximately 2 inches from the duct surface. The second measurement is made on the top of the exhaust pipe with the detector crystal 2 inches from the top of the duct. When the detector is placed in the bottom assay position, the area of the holdup material is assumed to extend beyond the detector field of view. The concentration of plutonium in g/cm 2 is obtained from this bottom measurement. The deposit width is determined from a model developed to relate the deposit width to the ratio of the count rates measured at the two positions, above and below the duct. Once a deposit width has been calculated, it is multiplied by the concentration determined from the bottom measurement to yield a mass- per-unit-length at the duct location. Total plutonium mass is then determined by multiplying the duct length by the average of the mass- per-unit length assays performed along the duct. The applicability of the technique is presented in a comparison of field measurement data to analysis results on material removed from the ducts. 3 refs., 3 figs., 1 tab

  10. Organic Rankine cycle for power recovery of exhaust flue gas

    International Nuclear Information System (INIS)

    Guo, Cong; Du, Xiaoze; Yang, Lijun; Yang, Yongping

    2015-01-01

    To study the effects of different working fluids on the performance of organic Rankine cycle (ORC), three working fluids, a mixture that matches with heat source, a mixture that matches with heat sink and a pure working fluid, are selected in this paper. Thermodynamic models were built in Matlab together with REFPROP, with which, the physical properties of the selected working fluids can be acquired. Heat source of the ORC system is the exhaust flue gas of boiler in a 240 MW pulverized coal-fired power plant. Some indicators such as thermal efficiency, inlet temperature of expander, superheat degree, mass flow, volumetric flow, and exergy destruction distribution, as well as the influence of recuperator are studied. The analytical results show that the mixture that matches with heat sink has the greatest efficiency and the mixture that matches with heat source has the lowest superheat degree. The rate of heat exchanged in recuperator to that in evaporator has a maximum value with evaporating pressure. There exists no optimal working fluid for all indicators (thermal efficiency, heat exchanger area, mass flow and volumetric flow etc.). An appropriate working fluid should be chosen by taking both investment cost and power generating benefits into account. The cost-benefit ratio of the proposed ORC plant was evaluated either. - Highlights: • Three types of working fluids are selected for ORC using exhaust flue gas. • The mixture that matches with heat sink has the greatest efficiency. • The mixture that matches with heat source has the lowest superheat degree. • There does not exist a working fluid that satisfies all the indicators

  11. Engine with pulse-suppressed dedicated exhaust gas recirculation

    Science.gov (United States)

    Keating, Edward J.; Baker, Rodney E.

    2016-06-07

    An engine assembly includes an intake assembly, a spark-ignited internal combustion engine, and an exhaust assembly. The intake assembly includes a charge air cooler disposed between an exhaust gas recirculation (EGR) mixer and a backpressure valve. The charge air cooler has both an inlet and an outlet, and the back pressure valve is configured to maintain a minimum pressure difference between the inlet of the charge air cooler and an outlet of the backpressure valve. A dedicated exhaust gas recirculation system is provided in fluid communication with at least one cylinder and with the EGR mixer. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the at least one cylinder to the EGR mixer for recirculation back to the engine.

  12. Infrared thermography application on predictive maintenance for exhaust fan motor

    International Nuclear Information System (INIS)

    I Wayan Widiana; Jakaria; Artadi Heru; Mulyono

    2013-01-01

    To determine the condition of the exhaust fan motor in terms of heat dissipation, predictive maintenance needs to be done. One way is to use infrared thermography. The method used is an infrared thermography with qualitative technique which the analysis focused on the distribution patterns of heat captured by the infrared camera. From measurement results expected to be obtained data of the heat distribution occurs in the motor exhaust fan so it can be given treatment or further improvements recommendations to avoid failure of the operation. Results of measurements on the motor exhaust fan 9 and the motor exhaust fan 10 indicates that there is excessive heat dissipation (over heating). The recommendation given is increasing the motor capacity of 11 kW to 18 kW with a consideration of the addition load on exhaust fan system and age of motor more than 22 years. (author)

  13. Dedicated exhaust gas recirculation control systems and methods

    Science.gov (United States)

    Sczomak, David P.; Narayanaswamy, Kushal; Keating, Edward J.

    2018-05-01

    An engine control system of a vehicle includes a fuel control module that controls fuel injection of a first cylinder of an engine based on a first target air/fuel ratio that is fuel lean relative to a stoichiometric air/fuel ratio and that controls fuel injection of a second cylinder of the engine based on a second target air/fuel ratio that is fuel rich relative to stoichiometry. The first cylinder outputs exhaust to a first three way catalyst (TWC), and the second cylinder outputs exhaust to an exhaust gas recirculation (EGR) valve. An EGR control module controls opening of the EGR valve to: (i) a second TWC that reacts with nitrogen oxides (NOx) in the exhaust and outputs ammonia to a selective catalytic reduction (SCR) catalyst; and (ii) a conduit that recirculates exhaust back to an intake system of the engine.

  14. The Glass Half Empty: How Emotional Exhaustion Affects the State-Trait Discrepancy in Self-Reports of Teaching Emotions.

    Science.gov (United States)

    Goetz, Thomas; Becker, Eva S; Bieg, Madeleine; Keller, Melanie M; Frenzel, Anne C; Hall, Nathan C

    2015-01-01

    Following from previous research on intensity bias and the accessibility model of emotional self-report, the present study examined the role of emotional exhaustion in explaining the discrepancy in teachers' reports of their trait (habitual) versus state (momentary, "real") emotions. Trait reports (habitual emotions, exhaustion) were assessed via trait questionnaires, and state reports (momentary emotions) were assessed in real time via the experience sampling method by using personal digital assistants (N = 69 high school teachers; 1,089 measures within teachers). In line with our assumptions, multi-level analyses showed that, as compared to the state assessment, teachers reported higher levels of habitual teaching-related emotions of anger, anxiety, shame, boredom, enjoyment, and pride. Additionally, the state-trait discrepancy in self-reports of negative emotions was accounted for by teachers' emotional exhaustion, with high exhaustion levels corresponding with a greater state-trait discrepancy. Exhaustion levels did not moderate the state-trait discrepancy in positive emotions indicating that perceived emotional exhaustion may reflect identity-related cognitions specific to the negative belief system. Implications for research and educational practice are discussed.

  15. The Glass Half Empty: How Emotional Exhaustion Affects the State-Trait Discrepancy in Self-Reports of Teaching Emotions

    Science.gov (United States)

    Goetz, Thomas; Becker, Eva S.; Bieg, Madeleine; Keller, Melanie M.; Frenzel, Anne C.; Hall, Nathan C.

    2015-01-01

    Following from previous research on intensity bias and the accessibility model of emotional self-report, the present study examined the role of emotional exhaustion in explaining the discrepancy in teachers’ reports of their trait (habitual) versus state (momentary, “real”) emotions. Trait reports (habitual emotions, exhaustion) were assessed via trait questionnaires, and state reports (momentary emotions) were assessed in real time via the experience sampling method by using personal digital assistants (N = 69 high school teachers; 1,089 measures within teachers). In line with our assumptions, multi-level analyses showed that, as compared to the state assessment, teachers reported higher levels of habitual teaching-related emotions of anger, anxiety, shame, boredom, enjoyment, and pride. Additionally, the state-trait discrepancy in self-reports of negative emotions was accounted for by teachers’ emotional exhaustion, with high exhaustion levels corresponding with a greater state-trait discrepancy. Exhaustion levels did not moderate the state-trait discrepancy in positive emotions indicating that perceived emotional exhaustion may reflect identity-related cognitions specific to the negative belief system. Implications for research and educational practice are discussed. PMID:26368911

  16. Associations between work family conflict, emotional exhaustion, musculoskeletal pain, and gastrointestinal problems in a sample of business travelers.

    Science.gov (United States)

    Jensen, Maria Therese; Rundmo, Torbjørn

    2015-02-01

    The aim of the study was to examine the associations among work-family conflict (WFC), emotional exhaustion, musculoskeletal (MS) pain, and gastrointestinal problems on a sample of business travelers (n = 2,093). An additional aim was to examine differences in the mentioned relationships among three traveler groups: commuters, national travelers, and international travelers. The study was conducted in a large Norwegian oil and gas company, and the company's business travel database was utilized to examine business travel. Structural equation modeling (SEM) revealed significant relations between WFC and emotional exhaustion and between emotional exhaustion and health problems. Contrary to the expectations, no direct association was found between WFC and health problems. However, we found that emotional exhaustion mediated the relation between WFC and health outcomes. The results from multi-group analysis revealed that associations among WFC, emotional exhaustion, and health-outcomes showed a similar pattern for commuters, national travelers, and international travelers. However, the association between emotional exhaustion and MS pain proved to be significantly stronger for the commuter group compared to the national and international travel groups. Practical implications and the consequences of these findings for future research are discussed. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  17. Measuring Stigma in Older and Younger Adults with HIV/AIDS: An Analysis of an HIV Stigma Scale and Initial Exploration of Subscales

    Science.gov (United States)

    Emlet, Charles A.

    2005-01-01

    The purpose of this study is to explore the validity of a scale designed to measure HIV stigma and identify potential subscales. A nonrandom sample of 88 individuals, 44 between the ages of 20 and 39 and 44 ages 50 and older, living with HIV/AIDS were interviewed and completed a 13-item HIV Stigma Scale. An exploratory factor analysis (EFA) found…

  18. Complex Relationships Among Masculine Norms and Health/Well-Being Outcomes: Correlation Patterns of the Conformity to Masculine Norms Inventory Subscales.

    Science.gov (United States)

    Gerdes, Zachary T; Levant, Ronald F

    2018-03-01

    The Conformity to Masculine Norms Inventory (CMNI) is a widely used multidimensional scale. Studies using the CMNI most often report only total scale scores, which are predominantly associated with negative outcomes. Various studies since the CMNI's inception in 2003 using subscales have reported both positive and negative outcomes. The current content analysis examined studies ( N = 17) correlating the 11 subscales with 63 criterion variables across 7 categories. Most findings were consistent with past research using total scale scores that reported negative outcomes. For example, conformity to masculine norms has been inversely related to help-seeking and positively correlated with concerning health variables, such as substance use. Nonetheless, past reliance on total scores has obscured the complexity of associations with the CMNI in that 30% of the findings in the present study reflected positive outcomes, particularly for health promotion. Subscales differed in their relationships with various outcomes: for one subscale they were predominantly positive, but six others were mostly negative. The situational and contextual implications of conformity to masculine norms and their relationships to positive and negative outcomes are discussed.

  19. Acceptance test procedure for SY Tank Farm replacement exhauster unit

    Energy Technology Data Exchange (ETDEWEB)

    Becken, G.W.

    1994-12-16

    The proper functioning of a new 241-SY Tank Farm replacement exhauster will be acceptance tested, to establish operability and to provide an operational baseline for the equipment. During this test, a verification of all of the alarm and control circuits associated with the exhaust, which provide operating controls and/or signals to local and remote alarm/annunciator panels, shall be performed. Test signals for sensors that provide alarms, warnings, and/or interlocks will be applied to verify that alarm, warning, and interlock setpoints are correct. Alarm and warning lights, controls, and local and remote readouts for the exhauster will be verified to be adequate for proper operation of the exhauster. Testing per this procedure shall be conducted in two phases. The first phase of testing, to verify alarm, warning, and interlock setpoints primarily, will be performed in the MO-566 Fab Shop. The second phase of testing, to verify proper operation and acceptable interface with other tank farm systems, will be conducted after the exhauster and all associated support and monitoring equipment have been installed in the SY Tank Farm. The exhauster, which is mounted on a skid and which will eventually be located in the SY tank farm, receives input signals from a variety of sensors mounted on the skid and associated equipment. These sensors provide information such as: exhauster system inlet vacuum pressure; prefilter and HEPA filter differential pressures; exhaust stack sampler status; exhaust fan status; system status (running/shut down); and radiation monitoring systems status. The output of these sensors is transmitted to the exhauster annunciator panel where the signals are displayed and monitored for out-of-specification conditions.

  20. Training for assessment of negative symptoms of schizophrenia across languages and cultures: comparison of the NSA-16 with the PANSS Negative Subscale and Negative Symptom factor.

    Science.gov (United States)

    Daniel, David G; Alphs, Larry; Cazorla, Pilar; Bartko, John J; Panagides, John

    2011-07-01

    The 16-item Negative Symptom Assessment scale (NSA-16) has been validated in English-speaking raters. We analyzed the level of agreement achieved among raters of different nationalities using the NSA-16 and the Positive and Negative Syndrome Scale (PANSS) negative subscale and Marder negative factor. Raters participating in two international trials were trained in the use of each instrument through lectures and feedback on their ratings of at least one videotaped interview of a schizophrenic patient. Overall and regional (North America, Western Europe, Eastern Europe, South/Central America, and Australia and South Africa combined) kappa values were calculated and mean total scores were compared (1-way analysis of variance) by region for each instrument. In addition, within-scales variance was calculated by item to help identify negative symptoms that were particularly challenging to obtain agreement on across cultures. In the combined group of international raters, the kappa values for ratings of the NSA-16, PANSS negative subscale, and Marder negative factors were 0.89, 0.84, and 0.82, respectively. Kappa values calculated by geographic region ranged from 0.87 to 0.94 for the NSA-16 compared with 0.82 to 0.86 for the PANSS negative subscale and 0.79 to 0.87 for the PANSS Marder negative factor. Despite cultural and linguistic differences among raters, standardizing measurement of negative symptoms in international clinical trials is possible using available rating scales: NSA-16, PANSS negative subscale, and Marder negative subscale. Agreement among raters was at least as high using the NSA-16 as using the PANSS instruments.

  1. Domain-specific cognitive effects of tramiprosate in patients with mild to moderate Alzheimer's disease: ADAS-cog subscale results from the Alphase Study.

    Science.gov (United States)

    Saumier, D; Duong, A; Haine, D; Garceau, D; Sampalis, J

    2009-11-01

    Tramiprosate (homotaurine, ALZHEMEDTM) was recently investigated for its efficacy, safety and disease-modification effects in a Phase III clinical study in mild to moderate Alzheimer's disease (AD) patients (the Alphase study). The primary cognitive endpoint measure of that study was the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog). To characterize potential cognitive benefits of tramiprosate, the present study describes exploratory analyses performed on scores obtained from the specific ADAS-cog subscales in order to determine whether specific domains of cognition may be differentially affected by tramiprosate, which would not have been evident from the measure's total score. Multi-center, double-blind, randomized, placebo-controlled study. 67 investigative sites in the United States and Canada. A total of 1,052 patients were randomized. Patients were randomized to receive twice a day Placebo (n=353), tramiprosate 100 mg (n=352) and tramiprosate 150 mg (n=347). ADAS-cog assessments were conducted every three months over the 78-week study period. Exploratory analyses were performed by comparing ADAS-cog subscale scores between Placebo and each active treatment arm at each visit. The findings of this analysis revealed statistically significant differences or statistical trends in favour of tramiprosate on six ADAS-cog subscales, namely Following Commands, Language Comprehension, Ideational Praxis, Object Naming, Remembering Test Instructions, and Spoken Language Ability. Differences in favor of Placebo were only observed on the Constructional Praxis subscale. This exploratory analysis suggests that tramiprosate may have some benefit on memory, language and praxis skills in mild to moderate AD individuals. Future clinical studies of tramiprosate should include specialized neuropsychological tests to validate its effects within these cognitive domains.

  2. Antisocial Personality Disorder Subscale (Chinese Version) of the Structured Clinical Interview for the DSM-IV Axis II disorders: validation study in Cantonese-speaking Hong Kong Chinese.

    Science.gov (United States)

    Tang, D Y Y; Liu, A C Y; Leung, M H T; Siu, B W M

    2013-06-01

    OBJECTIVE. Antisocial personality disorder (ASPD) is a risk factor for violence and is associated with poor treatment response when it is a co-morbid condition with substance abuse. It is an under-recognised clinical entity in the local Hong Kong setting, for which there are only a few available Chinese-language diagnostic instruments. None has been tested for its psychometric properties in the Cantonese-speaking population in Hong Kong. This study therefore aimed to assess the reliability and validity of the Chinese version of the ASPD subscale of the Structured Clinical Interview for the DSM-IV Axis II Disorders (SCID-II) in Hong Kong Chinese. METHODS. This assessment tool was modified according to dialectal differences between Mainland China and Hong Kong. Inpatients in Castle Peak Hospital, Hong Kong, who were designated for priority follow-up based on their assessed propensity for violence and who fulfilled the inclusion criteria for the study, were recruited. To assess the level of agreement, best-estimate diagnosis made by a multidisciplinary team was compared with diagnostic status determined by the SCID-II ASPD subscale. The internal consistency, sensitivity, and specificity of the subscale were also calculated. RESULTS. The internal consistency of the subscale was acceptable at 0.79, whereas the test-retest reliability and inter-rater reliability showed an excellent and good agreement of 0.90 and 0.86, respectively. Best-estimate clinical diagnosis-SCID diagnosis agreement was acceptable at 0.76. The sensitivity, specificity, positive and negative predictive values were 0.91, 0.86, 0.83, and 0.93, respectively. CONCLUSION. The Chinese version of the SCID-II ASPD subscale is reliable and valid for diagnosing ASPD in a Cantonese-speaking clinical population.

  3. Job crafting in changing organizations: Antecedents and implications for exhaustion and performance.

    Science.gov (United States)

    Petrou, Paraskevas; Demerouti, Evangelia; Schaufeli, Wilmar B

    2015-10-01

    The present study addressed employee job crafting behaviors (i.e., seeking resources, seeking challenges, and reducing demands) in the context of organizational change. We examined predictors of job crafting both at the organizational level (i.e., perceived impact of the implemented changes on the working life of employees) and the individual level (i.e., employee willingness to follow the changes). Job crafting behaviors were expected to predict task performance and exhaustion. Two-wave longitudinal data from 580 police officers undergoing organizational changes were analyzed with structural equation modeling. Findings showed that the degree to which changes influence employees' daily work was linked to reducing demands and exhaustion, whereas employee willingness to change was linked to seeking resources and seeking challenges. Furthermore, while seeking resources and seeking challenges were associated with high task performance and low exhaustion respectively, reducing demands seemed to predict exhaustion positively. Our findings suggest that job crafting can act as a strategy of employees to respond to organizational change. While seeking resources and seeking challenges enhance employee adjustment and should be encouraged by managers, reducing demands seems to have unfavorable implications for employees. (c) 2015 APA, all rights reserved).

  4. Recovery opportunities, work-home conflict, and emotional exhaustion among hematologists and oncologists in private practice.

    Science.gov (United States)

    Nitzsche, Anika; Neumann, Melanie; Groß, Sophie E; Ansmann, Lena; Pfaff, Holger; Baumann, Walter; Wirtz, Markus; Schmitz, Stephan; Ernstmann, Nicole

    2017-04-01

    Hematologists and oncologists in private practice play a central role in the care provided for cancer patients. The present study analyzes stress and relaxation aspects in the work of hematologists and oncologists in private practice in Germany in relation to emotional exhaustion, as a core dimension of burnout syndrome. The study focuses on the opportunities for internal recovery using breaks and time out during the working day, the frequency of working on weekends and on vacation, and the physician's work-home and home-work conflict. Postulated associations between the constructs were analyzed using a structural equation model. If work leads to conflicts in private life (work-home conflict), it is associated with greater emotional exhaustion. Working frequently at the weekend is associated with greater work-home conflict and indirectly with greater emotional exhaustion. By contrast, the availability of opportunities to relax and recover during the working day is associated with less work-home conflict and indirectly with less emotional exhaustion. These results underline the importance of internal recovery opportunities during the working day and a successful interplay between working and private life for the health of outpatient hematologists and oncologists.

  5. The Diesel Exhaust in Miners Study: IV. Estimating historical exposures to diesel exhaust in underground non-metal mining facilities.

    Science.gov (United States)

    Vermeulen, Roel; Coble, Joseph B; Lubin, Jay H; Portengen, Lützen; Blair, Aaron; Attfield, Michael D; Silverman, Debra T; Stewart, Patricia A

    2010-10-01

    We developed quantitative estimates of historical exposures to respirable elemental carbon (REC) for an epidemiologic study of mortality, including lung cancer, among diesel-exposed miners at eight non-metal mining facilities [the Diesel Exhaust in Miners Study (DEMS)]. Because there were no historical measurements of diesel exhaust (DE), historical REC (a component of DE) levels were estimated based on REC data from monitoring surveys conducted in 1998-2001 as part of the DEMS investigation. These values were adjusted for underground workers by carbon monoxide (CO) concentration trends in the mines derived from models of historical CO (another DE component) measurements and DE determinants such as engine horsepower (HP; 1 HP = 0.746 kW) and mine ventilation. CO was chosen to estimate historical changes because it was the most frequently measured DE component in our study facilities and it was found to correlate with REC exposure. Databases were constructed by facility and year with air sampling data and with information on the total rate of airflow exhausted from the underground operations in cubic feet per minute (CFM) (1 CFM = 0.0283 m³ min⁻¹), HP of the diesel equipment in use (ADJ HP), and other possible determinants. The ADJ HP purchased after 1990 (ADJ HP₁₉₉₀(+)) was also included to account for lower emissions from newer, cleaner engines. Facility-specific CO levels, relative to those in the DEMS survey year for each year back to the start of dieselization (1947-1967 depending on facility), were predicted based on models of observed CO concentrations and log-transformed (Ln) ADJ HP/CFM and Ln(ADJ HP₁₉₉₀(+)). The resulting temporal trends in relative CO levels were then multiplied by facility/department/job-specific REC estimates derived from the DEMS surveys personal measurements to obtain historical facility/department/job/year-specific REC exposure estimates. The facility-specific temporal trends of CO levels (and thus the REC

  6. Integration of a molten carbonate fuel cell with a direct exhaust absorption chiller

    Science.gov (United States)

    Margalef, Pere; Samuelsen, Scott

    A high market value exists for an integrated high-temperature fuel cell-absorption chiller product throughout the world. While high-temperature, molten carbonate fuel cells are being commercially deployed with combined heat and power (CHP) and absorption chillers are being commercially deployed with heat engines, the energy efficiency and environmental attributes of an integrated high-temperature fuel cell-absorption chiller product are singularly attractive for the emerging distributed generation (DG) combined cooling, heating, and power (CCHP) market. This study addresses the potential of cooling production by recovering and porting the thermal energy from the exhaust gas of a high-temperature fuel cell (HTFC) to a thermally activated absorption chiller. To assess the practical opportunity of serving an early DG-CCHP market, a commercially available direct fired double-effect absorption chiller is selected that closely matches the exhaust flow and temperature of a commercially available HTFC. Both components are individually modeled, and the models are then coupled to evaluate the potential of a DG-CCHP system. Simulation results show that a commercial molten carbonate fuel cell generating 300 kW of electricity can be effectively coupled with a commercial 40 refrigeration ton (RT) absorption chiller. While the match between the two "off the shelf" units is close and the simulation results are encouraging, the match is not ideal. In particular, the fuel cell exhaust gas temperature is higher than the inlet temperature specified for the chiller and the exhaust flow rate is not sufficient to achieve the potential heat recovery within the chiller heat exchanger. To address these challenges, the study evaluates two strategies: (1) blending the fuel cell exhaust gas with ambient air, and (2) mixing the fuel cell exhaust gases with a fraction of the chiller exhaust gas. Both cases are shown to be viable and result in a temperature drop and flow rate increase of the

  7. Integration of a molten carbonate fuel cell with a direct exhaust absorption chiller

    Energy Technology Data Exchange (ETDEWEB)

    Margalef, Pere; Samuelsen, Scott [National Fuel Cell Research Center (NFCRC), University of California, Irvine, CA 92697-3550 (United States)

    2010-09-01

    A high market value exists for an integrated high-temperature fuel cell-absorption chiller product throughout the world. While high-temperature, molten carbonate fuel cells are being commercially deployed with combined heat and power (CHP) and absorption chillers are being commercially deployed with heat engines, the energy efficiency and environmental attributes of an integrated high-temperature fuel cell-absorption chiller product are singularly attractive for the emerging distributed generation (DG) combined cooling, heating, and power (CCHP) market. This study addresses the potential of cooling production by recovering and porting the thermal energy from the exhaust gas of a high-temperature fuel cell (HTFC) to a thermally activated absorption chiller. To assess the practical opportunity of serving an early DG-CCHP market, a commercially available direct fired double-effect absorption chiller is selected that closely matches the exhaust flow and temperature of a commercially available HTFC. Both components are individually modeled, and the models are then coupled to evaluate the potential of a DG-CCHP system. Simulation results show that a commercial molten carbonate fuel cell generating 300 kW of electricity can be effectively coupled with a commercial 40 refrigeration ton (RT) absorption chiller. While the match between the two ''off the shelf'' units is close and the simulation results are encouraging, the match is not ideal. In particular, the fuel cell exhaust gas temperature is higher than the inlet temperature specified for the chiller and the exhaust flow rate is not sufficient to achieve the potential heat recovery within the chiller heat exchanger. To address these challenges, the study evaluates two strategies: (1) blending the fuel cell exhaust gas with ambient air, and (2) mixing the fuel cell exhaust gases with a fraction of the chiller exhaust gas. Both cases are shown to be viable and result in a temperature drop and flow

  8. Analysis of vehicle exhaust waste heat recovery potential using a Rankine cycle

    International Nuclear Information System (INIS)

    Domingues, António; Santos, Helder; Costa, Mário

    2013-01-01

    This study evaluates the vehicle exhaust WHR (waste heat recovery) potential using a RC (Rankine cycle ). To this end, both a RC thermodynamic model and a heat exchanger model have been developed. Both models use as input, experimental data obtained from a vehicle tested on a chassis dynamometer. The thermodynamic analysis was performed for water, R123 and R245fa and revealed the advantage of using water as the working fluid in applications of thermal recovery from exhaust gases of vehicles equipped with a spark-ignition engine. Moreover, the heat exchanger effectiveness for the organic working fluids R123 and R245fa is higher than that for the water and, consequently, they can also be considered appropriate for use in vehicle WHR applications through RCs when the exhaust gas temperatures are relatively low. For an ideal heat exchanger, the simulations revealed increases in the internal combustion engine thermal and vehicle mechanical efficiencies of 1.4%–3.52% and 10.16%–15.95%, respectively, while for a shell and tube heat exchanger, the simulations showed an increase of 0.85%–1.2% in the thermal efficiency and an increase of 2.64%–6.96% in the mechanical efficiency for an evaporating pressure of 2 MPa. The results confirm the advantages of using the thermal energy contained in the vehicle exhaust gases through RCs. Furthermore, the present analysis demonstrates that improved evaporator designs and appropriate expander devices allowing for higher evaporating pressures are required to obtain the maximum WHR potential from vehicle RC systems. -- Highlights: ► This study evaluates the vehicle exhaust waste heat recovery potential using Rankine cycle systems. ► A thermodynamic model and a heat exchanger model were developed. ► Experimental data obtained in a vehicle tested on a chassis dynamometer was used as models input. ► Thermodynamic analysis was performed for water, R123 and R245fa. ► Results confirm advantages of using the thermal energy

  9. New catalysts for exhaust gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, M [Kemira Metalkat Oy, Oulu (Finland)

    1997-12-31

    Major challenge for future catalyst systems was to develop thermally more stable washcoats for close coupled operating conditions and for engines operating under high speed and load conditions. To design these future emission systems extensive research and development was undertaken to develop methods to disperse and stabilize the key catalytic materials for operation at much higher temperatures. Second priority was to design catalysts that are more effective under low temperature exhaust conditions and have improved oxygen storage properties in the washcoats. Incorporating new materials and modified preparation technology a new generation of metallic catalyst formulations emerged, those being trimetallic K6 (Pt:Pd:Rh and bimetallic K7) (Pd+Pd:Rh). The target was to combine the best property of Pt:Rh (good NO{sub x} reduction) with that of the good HC oxidation activity of Pd and to ensure that precious metal/support interactions were positively maintained. Both K6 and K7 concepts contain special catalyst structures with optimized washcoat performance which can be brick converter configuration. Improvement in light-off, thermal stability and transient performance with these new catalyst formulations have clearly been shown in both laboratory and vehicle testing. (author) (20 refs.)

  10. New catalysts for exhaust gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, M. [Kemira Metalkat Oy, Oulu (Finland)

    1996-12-31

    Major challenge for future catalyst systems was to develop thermally more stable washcoats for close coupled operating conditions and for engines operating under high speed and load conditions. To design these future emission systems extensive research and development was undertaken to develop methods to disperse and stabilize the key catalytic materials for operation at much higher temperatures. Second priority was to design catalysts that are more effective under low temperature exhaust conditions and have improved oxygen storage properties in the washcoats. Incorporating new materials and modified preparation technology a new generation of metallic catalyst formulations emerged, those being trimetallic K6 (Pt:Pd:Rh and bimetallic K7) (Pd+Pd:Rh). The target was to combine the best property of Pt:Rh (good NO{sub x} reduction) with that of the good HC oxidation activity of Pd and to ensure that precious metal/support interactions were positively maintained. Both K6 and K7 concepts contain special catalyst structures with optimized washcoat performance which can be brick converter configuration. Improvement in light-off, thermal stability and transient performance with these new catalyst formulations have clearly been shown in both laboratory and vehicle testing. (author) (20 refs.)

  11. Neutron activation analysis of automobile exhaust pollutants

    International Nuclear Information System (INIS)

    Oakes, T.W.; Furr, A.K.; Adair, D.J.; Parkinson, T.F.

    1977-01-01

    An approximation of the distribution of lead particulate from vehicular exhausts is given. Soil and grass (Poa trivialis) samples were collected at five-foot intervals from the roadside out to 300 feet, at ten-foot intervals from 300 to 350 feet, and at 25-foot intervals from 350 to 600 feet. All samples were irradiated twice: once for a brief period of from 10 to 120 seconds and later for periods of from 6 to 8 hours. The short irradiations were at a thermal neutron flux of 1.2x10 12 ncm -2 sec -1 (decay time=1 min, counting time=8 min). The long irradiations were at a thermal neutron flux of 1.3x10 12 ncm -2 sec -1 , and the samples counted twice at decay intervals of two days and twelve days. The counting intervals were one hour. The spectra were stored on magnetic tape for processing by an IBM 370/158 computer. This initial neutron-activation analysis study has shown that there is an extremely detailed pattern of the effluent from vehicular highway traffic which is strongly affected by micrometeorological conditions. In order to detect these patterns it is necessary to use a very compact sample grid with every possible precaution taken to ensure sample homogeneity and cleanliness. A possibility of elevated levels of pollution may exist at considerable distances from the highway, perhaps even greater than at the immediate roadside. (T.G.)

  12. Construct Validity and Reliability of the SARA Gait and Posture Sub-scale in Early Onset Ataxia

    Directory of Open Access Journals (Sweden)

    Tjitske F. Lawerman

    2017-12-01

    Full Text Available Aim: In children, gait and posture assessment provides a crucial marker for the early characterization, surveillance and treatment evaluation of early onset ataxia (EOA. For reliable data entry of studies targeting at gait and posture improvement, uniform quantitative biomarkers are necessary. Until now, the pediatric test construct of gait and posture scores of the Scale for Assessment and Rating of Ataxia sub-scale (SARA is still unclear. In the present study, we aimed to validate the construct validity and reliability of the pediatric (SARAGAIT/POSTURE sub-scale.Methods: We included 28 EOA patients [15.5 (6–34 years; median (range]. For inter-observer reliability, we determined the ICC on EOA SARAGAIT/POSTURE sub-scores by three independent pediatric neurologists. For convergent validity, we associated SARAGAIT/POSTURE sub-scores with: (1 Ataxic gait Severity Measurement by Klockgether (ASMK; dynamic balance, (2 Pediatric Balance Scale (PBS; static balance, (3 Gross Motor Function Classification Scale -extended and revised version (GMFCS-E&R, (4 SARA-kinetic scores (SARAKINETIC; kinetic function of the upper and lower limbs, (5 Archimedes Spiral (AS; kinetic function of the upper limbs, and (6 total SARA scores (SARATOTAL; i.e., summed SARAGAIT/POSTURE, SARAKINETIC, and SARASPEECH sub-scores. For discriminant validity, we investigated whether EOA co-morbidity factors (myopathy and myoclonus could influence SARAGAIT/POSTURE sub-scores.Results: The inter-observer agreement (ICC on EOA SARAGAIT/POSTURE sub-scores was high (0.97. SARAGAIT/POSTURE was strongly correlated with the other ataxia and functional scales [ASMK (rs = -0.819; p < 0.001; PBS (rs = -0.943; p < 0.001; GMFCS-E&R (rs = -0.862; p < 0.001; SARAKINETIC (rs = 0.726; p < 0.001; AS (rs = 0.609; p = 0.002; and SARATOTAL (rs = 0.935; p < 0.001]. Comorbid myopathy influenced SARAGAIT/POSTURE scores by concurrent muscle weakness, whereas comorbid myoclonus predominantly influenced

  13. The green paradox of the economics of exhaustible resources

    International Nuclear Information System (INIS)

    Cairns, Robert D.

    2014-01-01

    The green paradox states that an increasing tax on emissions of carbon dioxide, consonant with the expected increase in their marginal damages, may induce oil producers to shift their production toward the present and thereby to exacerbate the problem of climatic change. The model is based on Hotelling models of resource use that do not take the natural and technical features of oil production into account. Natural features include the decline of production through time according to a decline curve. Technical features include the requirement to sink investment in productive capacity. A model of a profit-maximizing firm indicates that, if these features are taken into account, the prediction of the green paradox is unlikely. - Highlights: • The green paradox is a direct application of Hotelling′s rule from the economics of exhaustible resources. • Hotelling′s analysis was a profound contribution to economic thought but evidence for it is weak. • Hotelling-style analysis assumes incorrectly that production can be rearranged at will among time periods. • Technological and geological features of oil production make the prediction of the green paradox unlikely

  14. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    Science.gov (United States)

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  15. Capture of Heat Energy from Diesel Engine Exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Chuen-Sen Lin

    2008-12-31

    Diesel generators produce waste heat as well as electrical power. About one-third of the fuel energy is released from the exhaust manifolds of the diesel engines and normally is not captured for useful applications. This project studied different waste heat applications that may effectively use the heat released from exhaust of Alaskan village diesel generators, selected the most desirable application, designed and fabricated a prototype for performance measurements, and evaluated the feasibility and economic impact of the selected application. Exhaust flow rate, composition, and temperature may affect the heat recovery system design and the amount of heat that is recoverable. In comparison with the other two parameters, the effect of exhaust composition may be less important due to the large air/fuel ratio for diesel engines. This project also compared heat content and qualities (i.e., temperatures) of exhaust for three types of fuel: conventional diesel, a synthetic diesel, and conventional diesel with a small amount of hydrogen. Another task of this project was the development of a computer-aided design tool for the economic analysis of selected exhaust heat recovery applications to any Alaskan village diesel generator set. The exhaust heat recovery application selected from this study was for heating. An exhaust heat recovery system was fabricated, and 350 hours of testing was conducted. Based on testing data, the exhaust heat recovery heating system showed insignificant effects on engine performance and maintenance requirements. From measurements, it was determined that the amount of heat recovered from the system was about 50% of the heat energy contained in the exhaust (heat contained in exhaust was evaluated based on environment temperature). The estimated payback time for 100% use of recovered heat would be less than 3 years at a fuel price of $3.50 per gallon, an interest rate of 10%, and an engine operation of 8 hours per day. Based on experimental data

  16. High-speed schlieren imaging of rocket exhaust plumes

    Science.gov (United States)

    Coultas-McKenney, Caralyn; Winter, Kyle; Hargather, Michael

    2016-11-01

    Experiments are conducted to examine the exhaust of a variety of rocket engines. The rocket engines are mounted in a schlieren system to allow high-speed imaging of the engine exhaust during startup, steady state, and shutdown. A variety of rocket engines are explored including a research-scale liquid rocket engine, consumer/amateur solid rocket motors, and water bottle rockets. Comparisons of the exhaust characteristics, thrust and cost for this range of rockets is presented. The variety of nozzle designs, target functions, and propellant type provides unique variations in the schlieren imaging.

  17. Exhaustion Experiences in Junior Athletes:The Importance of Motivation and Self - Control Competencies

    Directory of Open Access Journals (Sweden)

    Gro Jordalen

    2016-11-01

    Full Text Available Quality of motivation, self-control competencies, as well as past performance experience influence sport participation outcomes in developing athletes. Studies have shown that junior athletes high in self-determined motivation are less prone to experience burnout, while self-control competencies help developing athletes to be conscious and deliberate in their self-regulatory efforts toward elite sport performances and avoid negative sport participation outcomes. Combining the self-determination theory (SDT framework and psychosocial theories of self-regulation, the aim of this cross-sectional study was to examine how various types of motivation and self-control competencies together are associated with the development of burnout symptoms in junior athletes. High-level Norwegian winter-sport athletes from elite sport academies (N = 199; female n = 72; 16 to 20 years of age consented to participate. Associations between six types of motivational regulation, self-control, and indices of exhaustion were investigated. We hypothesized that athletes’ self-control competencies are important to operate successfully, and influenced by different types of motivation, they are expected to help athletes avoid negative sport participation outcomes such as emotional and physical exhaustion. Structural equation modeling analyses were conducted to analyze these relationships, and results revealed some multifaceted associations. When identifying antecedents of sport participation exhaustion and burnout, there is a need to go beyond the unique framework of motivation theories, and explore what cognitive competencies ensure fulfillment of motivation desires. In the current study, differences in junior athletes’ quality of motivation influenced self-control competencies when predicting exhaustion. Interestingly, young athletes driven by self-determined (intrinsic, integrated, and identified, and controlled (introjected and amotivation regulations in association

  18. Exhaustion Experiences in Junior Athletes: The Importance of Motivation and Self-Control Competencies.

    Science.gov (United States)

    Jordalen, Gro; Lemyre, Pierre-Nicolas; Durand-Bush, Natalie

    2016-01-01

    Quality of motivation, self-control competencies, as well as past performance experience influence sport participation outcomes in developing athletes. Studies have shown that junior athletes high in self-determined motivation are less prone to experience burnout, while self-control competencies help developing athletes to be conscious and deliberate in their self-regulatory efforts toward elite sport performances and avoid negative sport participation outcomes. Combining the self-determination theory framework and psychosocial theories of self-regulation, the aim of this cross-sectional study was to examine how various types of motivation and self-control competencies together are associated with the development of burnout symptoms in junior athletes. High-level Norwegian winter-sport athletes from elite sport academies ( N = 199; female n = 72; 16-20 years of age) consented to participate. Associations between six types of motivational regulation, self-control, and indices of exhaustion were investigated. We hypothesized that athletes' self-control competencies are important to operate successfully, and influenced by different types of motivation, they are expected to help athletes avoid negative sport participation outcomes such as emotional and physical exhaustion. Structural equation modeling analyses were conducted to analyze these relationships, and results revealed some multifaceted associations. When identifying antecedents of sport participation exhaustion and burnout, there is a need to go beyond the unique framework of motivation theories, and explore what cognitive competencies ensure fulfillment of motivation desires. In the current study, differences in junior athletes' quality of motivation influenced self-control competencies when predicting exhaustion. Interestingly, young athletes driven by self-determined (intrinsic, integrated, and identified), and controlled (introjected and amotivation) regulations in association with self-control offered the

  19. A combined thermodynamic cycle based on methanol dissociation for IC (internal combustion) engine exhaust heat recovery

    International Nuclear Information System (INIS)

    Fu, Jianqin; Liu, Jingping; Xu, Zhengxin; Ren, Chengqin; Deng, Banglin

    2013-01-01

    In this paper, a novel approach for exhaust heat recovery was proposed to improve IC (internal combustion) engine fuel efficiency and also to achieve the goal for direct usage of methanol as IC engine fuel. An open organic Rankine cycle system using methanol as working medium is coupled to IC engine exhaust pipe for exhaust heat recovery. In the bottom cycle, the working medium first undergoes dissociation and expansion processes, and is then directed back to IC engine as fuel. As the external bottom cycle and the IC engine main cycle are combined together, this scheme forms a combined thermodynamic cycle. Then, this concept was applied to a turbocharged engine, and the corresponding simulation models were built for both of the external bottom cycle and the IC engine main cycle. On this basis, the energy saving potential of this combined cycle was estimated by parametric analyses. Compared to the methanol vapor engine, IC engine in-cylinder efficiency has an increase of 1.4–2.1 percentage points under full load conditions, while the external bottom cycle can increase the fuel efficiency by 3.9–5.2 percentage points at the working pressure of 30 bar. The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points. - Highlights: • A combined thermodynamic cycle using methanol as working medium for IC engine exhaust heat recovery is proposed. • The external bottom cycle of exhaust heat recovery and IC engine working cycle are combined together. • IC engine fuel efficiency could be improved from both in-cylinder working cycle and external bottom cycle. • The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points at full load

  20. Passion for work and emotional exhaustion: the mediating role of rumination and recovery.

    Science.gov (United States)

    Donahue, Eric G; Forest, Jacques; Vallerand, Robert J; Lemyre, Pierre-Nicolas; Crevier-Braud, Laurence; Bergeron, Eliane

    2012-11-01

    The purpose of the present research is to present a model pertaining to the mediating roles of rumination and recovery experiences in the relationship between a harmonious and an obsessive passion (Vallerand et al., 2003) for work and workers' emotional exhaustion. Two populations were measured in the present research: namely elite coaches and nurses. Study 1's model posits that obsessive passion positively predicts rumination about one's work when being physically away from work, while harmonious passion negatively predicts ruminative thoughts. In turn, rumination is expected to positively contribute to emotional exhaustion. The results of Study 1 were replicated in Study 2. In addition, in the model of Study 2, obsessive passion was expected to undermine recovery experiences, while harmonious passion was expected to predict recovery experiences. In turn, recovery experiences were expected to protect workers from emotional exhaustion. Results of both studies provided support for the proposed model. The present findings demonstrate that passion for work may lead to some adaptive and maladaptive psychological processes depending on the type of passion that is prevalent. © 2012 The Authors. Applied Psychology: Health and Well-Being © 2012 The International Association of Applied Psychology.

  1. Numerical simulation of interaction between chemically active exhaust and a jet blast deflector

    Science.gov (United States)

    Korotaeva, T. A.; Turchinovich, A. O.

    2017-10-01

    The interaction of chemically active exhausts of aircraft engines with jet blast deflector (JBD) of various configurations has been considered at the stage of ground run procedure. The problem is modeled in the 3-D approximation in the framework of the numerical solution of the Navier-Stokes equations taking into account the kinetic model of the interaction of between the components of engine exhaust and air. A complex field of gasdynamic flow that is realized when jets emerge from nozzles and interact with each other, with air, with a gas deflector has been studied. The main purpose of the study is to prove the concept that it is possible to generate a vortex flow that can not only change the direction of the jets, but also contribute to the lifting of the mass of pollutants and their dispersion in the atmosphere using a gas deflector shape.

  2. A parametric design of compact exhaust manifold junction in heavy duty diesel engine using CFD

    Directory of Open Access Journals (Sweden)

    Naeimi Hessamedin

    2011-01-01

    Full Text Available Nowadays, computational fluid dynamics codes (CFD are prevalently used to simulate the gas dynamics in many fluid piping systems such as steam and gas turbines, inlet and exhaust in internal combustion engines. In this paper, a CFD software is used to obtain the total energy losses in adiabatic compressible flow at compact exhaust manifold junction. A steady state onedimensional adiabatic compressible flow with friction model has been applied to subtract the straight pipe friction losses from the total energy losses. The total pressure loss coefficient has been related to the extrapolated Mach number in the common branch and to the mass flow rate ratio between branches at different flow configurations, in both combining and dividing flows. The study indicate that the numerical results were generally in good agreement with those of experimental data from the literature and will be applied as a boundary condition in one-dimensional global simulation models of fluid systems in which these components are present.

  3. LETTER TO THE EDITOR: Exhaustive search for low-autocorrelation binary sequences

    Science.gov (United States)

    Mertens, S.

    1996-09-01

    Binary sequences with low autocorrelations are important in communication engineering and in statistical mechanics as ground states of the Bernasconi model. Computer searches are the main tool in the construction of such sequences. Owing to the exponential size 0305-4470/29/18/005/img1 of the configuration space, exhaustive searches are limited to short sequences. We discuss an exhaustive search algorithm with run-time characteristic 0305-4470/29/18/005/img2 and apply it to compile a table of exact ground states of the Bernasconi model up to N = 48. The data suggest F > 9 for the optimal merit factor in the limit 0305-4470/29/18/005/img3.

  4. Individual- and Organization-level Work-to-Family Spillover are Uniquely Associated with Hotel Managers' Work Exhaustion and Satisfaction

    Directory of Open Access Journals (Sweden)

    Soomi Lee

    2016-08-01

    Full Text Available Purpose: Building on the Conservation of Resources theory, this paper examined the unique and interactive associations of negative and positive work-to-family spillover (NWFS and PWFS, respectively at the individual and organizational level with hotel managers’ wok exhaustion and satisfaction, beyond job demands and supervisors’ leadership style. Design/methodology/approach: Guided by the levels of analysis framework, we first tested the unique associations of NWFS and PWFS with emotional exhaustion and job satisfaction at the individual level (571 hotel managers, beyond job demands supervisors’ leadership style. Second, using multilevel modeling, we tested the climate effects of NWFS and PWFS on emotional exhaustion and job satisfaction aggregated at the organizational level (41 hotels. Third, we examined the role of the organizational climate of PWFS in the associations of individual-level NWFS with emotional exhaustion and job satisfaction. Findings: Beyond the effects of psychological job demands and supervisor’s transformational leadership, at the individual level, hotel managers who experienced higher NWFS than other managers reported more exhaustion and lower job satisfaction, whereas those with higher PWFS reported less exhaustion and higher satisfaction. At the organizational level, working in hotels where the average level of NWFS was higher than other hotels was associated with feeling more exhaustion of the individual members; working in hotels with higher PWFS was associated with feeling less exhaustion. The negative link between individual-level NWFS and job satisfaction was buffered when organization-level PWFS was higher, compared to when it was lower. Originality/value: This study moves beyond a focus on traditional job characteristics, toward considering individual and organizational experiences in the work-family interface as unique predictors of work exhaustion and satisfaction. Strengths of the study include

  5. Dose Rate Calculations for Rotary Mode Core Sampling Exhauster

    CERN Document Server

    Foust, D J

    2000-01-01

    This document provides the calculated estimated dose rates for three external locations on the Rotary Mode Core Sampling (RMCS) exhauster HEPA filter housing, per the request of Characterization Field Engineering.

  6. Dose Rate Calculations for Rotary Mode Core Sampling Exhauster

    International Nuclear Information System (INIS)

    FOUST, D.J.

    2000-01-01

    This document provides the calculated estimated dose rates for three external locations on the Rotary Mode Core Sampling (RMCS) exhauster HEPA filter housing, per the request of Characterization Field Engineering

  7. Effect Effects of Auricularia auricula Polysaccharides on Exhaustive ...

    African Journals Online (AJOL)

    Exhaustive Swimming Exercise-Induced Oxidative Stress in Mice. Haitao Hao .... of the College of Life Sciences, China Jiliang. University ..... The delicate physiological balance between oxidative ... This work was supported by funds from.

  8. Surface chloride salt formation on Space Shuttle exhaust alumina

    Science.gov (United States)

    Cofer, W. R., III; Pellett, G. L.; Sebacher, D. I.; Wakelyn, N. T.

    1984-01-01

    Aluminum oxide samples from the exhaust of Space Shuttle launches STS-1, STS-4, STS-5, and STS-6 were collected from surfaces on or around the launch pad complex and chemically analyzed. The results indicate that the particulate solid-propellant rocket motor (SRM) alumina was heavily chlorided. Concentrations of water-soluble aluminum (III) ion were large, suggesting that the surface of the SRM alumina particles was rendered soluble by prior reactions with HCl and H2O in the SRM exhaust cloud. These results suggest that Space Shuttle exhaust alumina particles are good sites for nucleation and condensation of atmospheric water. Laboratory experiments conducted at 220 C suggest that partial surface chloriding of alumina may occur in hot Space Shuttle exhaust plumes.

  9. Muscle interstitial potassium kinetics during intense exhaustive exercise

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai; Mohr, Magni; Pedersen, Lasse Dannemann

    2003-01-01

    Interstitial K+ ([K+]i) was measured in human skeletal muscle by microdialysis during exhaustive leg exercise, with (AL) and without (L) previous intense arm exercise. In addition, the reproducibility of the [K+]i determinations was examined. Possible microdialysis-induced rupture of the sarcolemma...... was assessed by measurement of carnosine in the dialysate, because carnosine is only expected to be found intracellularly. Changes in [K+]i could be reproduced, when exhaustive leg exercise was performed on two different days, with a between-day difference of approximately 0.5 mM at rest and 1.5 m......M at exhaustion. The time to exhaustion was shorter in AL than in L (2.7 +/- 0.3 vs. 4.0 +/- 0.3 min; P exercise period in AL compared with L (9.2 +/- 0.7 vs. 6.4 +/- 0.9 mM; P

  10. Effect of diesel generator exhaust pollutants on growth of Vinca ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: The effects of exhaust pollutants of generator on root and shoot length, root and shoot weight, number of .... single cylinders with cooling system of air dry. The frequency is 50 .... and reproduction along CO2 gradients. Nonlinear.

  11. Exhaust gas purifying system for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Minami, H; Saito, Z

    1976-10-07

    The exhaust gas purification system is a so-called three-way catalytic converter. It consists of an oxidation converter, a reduction converter, or a thermal converter. An exhaust sensor made up of an oxygen sensor, a carbon sensor, a carbon monoxide sensor, hydrocarbon sensor, or a nitrogen peroxide sensor, tests the composition of the exhaust and controls the air-fuel feed system in dependence of the exhaust mixture in such a manner that in the intake system an air-fuel mixture is taken in which the stoichiometric air-fuel relation is produced. Moreover, a thermostatically controlled air intake device is built into the fuel injection system which supplies the air of the fuel injection system with a relatively consistent temperature.

  12. Role Stress and Emotional Exhaustion Among Health Care Workers: The Buffering Effect of Supportive Coworker Climate in a Multilevel Perspective.

    Science.gov (United States)

    Portoghese, Igor; Galletta, Maura; Burdorf, Alex; Cocco, Pierluigi; D'Aloja, Ernesto; Campagna, Marcello

    2017-10-01

    The aim of the study was to examine the relationship between role stress, emotional exhaustion, and a supportive coworker climate among health care workers, by adopting a multilevel perspective. Aggregated data of 738 health care workers nested within 67 teams of three Italian hospitals were collected. Multilevel regression analysis with a random intercept model was used. Hierarchical linear modeling showed that a lack of role clarity was significantly linked to emotional exhaustion at the individual level. At the unit level, the cross-level interaction revealed that a supportive coworker climate moderated the relationship between lack of role clarity and emotional exhaustion. This study supports previous results of single-level burnout studies, extending the existing literature with evidence on the multidimensional and cross-level interaction associations of a supportive coworker climate as a key aspect of job resources on burnout.

  13. Biophysical Assessment of Single Cell Cytotoxicity: Diesel Exhaust Particle-Treated Human Aortic Endothelial Cells

    OpenAIRE

    Wu, Yangzhe; Yu, Tian; Gilbertson, Timothy A.; Zhou, Anhong; Xu, Hao; Nguyen, Kytai Truong

    2012-01-01

    Exposure to diesel exhaust particles (DEPs), a major source of traffic-related air pollution, has become a serious health concern due to its adverse influences on human health including cardiovascular and respiratory disorders. To elucidate the relationship between biophysical properties (cell topography, cytoskeleton organizations, and cell mechanics) and functions of endothelial cells exposed to DEPs, atomic force microscope (AFM) was applied to analyze the toxic effects of DEPs on a model ...

  14. The Effects of Knowledge Accumulation on Intergenerational Allocation of an Exhaustible Resource with Amenity Value

    OpenAIRE

    CAI, Dapeng

    2002-01-01

    This paper analyzes equilibrium intergenerational allocation of an exhaustible resource with amenity value in an overlapping generations (OLG) economy. The paper first reviews two allocation schemes and concludes the ‘trust fund’ scheme, which is deemed to be ‘intergenerationally democratic’, is preferred to the ‘grandfathering’ scheme, which represents the business-as usual practice of resource use. It then introduces knowledge accumulation into the model by imposing a public R&D sector th...

  15. Exhaustible natural resources, normal prices and intertemporal equilibrium

    OpenAIRE

    Parrinello, Sergio

    2003-01-01

    This paper proposes an extension of the classical theory of normal prices to an n-commodity economy with exhaustible natural resources. The central idea is developed by two analytical steps. Firstly, it is assumed that a given flow of an exhaustible resource in short supply is combined with the coexistence of two methods of production using that resource. Sraffa’s equations are reinterpreted by adopting the concept of effectual supply of natural resources and avoiding the assumption of perfec...

  16. A system recovering heat from exhaust gases. Abgasenergie-Rueckgewinnungseinrichtung

    Energy Technology Data Exchange (ETDEWEB)

    John, E; Hultsch, H; Brendorp, W

    1990-08-16

    The proposed exhaust gas heat recovery system is provided with a hydraulic clutch (8) which is located between a gas tubine (2) to be driven by the exhaust gases of an internal combustion engine (20) and a drive unit (18) of the internal combustion engine (20). A mechanical blocking device (6) prevents the turbine from running at explosion speed when the hydraulic clutch (8) is emptied or when the oil pressure of the hydraulic clutch drops below a certain minimum.

  17. Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-15-1-0644 TITLE: Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells PRINCIPAL INVESTIGATOR: Chun-Ju...Targeting Cell Polarity Machinery to Exhaust Breast Cancer Stem Cells 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-15-1-0644 5c. PROGRAM ELEMENT...Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Cancer stem cells (CSCs), a cell population with acquired perpetuating self-renewal properties which

  18. LOFT diesel generator ''A'' exhaust stack seismic analysis

    International Nuclear Information System (INIS)

    Blandford, R.K.

    1978-01-01

    A stress analysis of the LOFT Diesel Generator ''A'' Exhaust Stack was performed to determine its reaction to Safe-Shutdown Earthquake loads. The exhaust stack silencer and supporting foundation was found to be inadequate for the postulated seismic accelerations. Lateral support is required to prevent overturning of the silencer pedestal and reinforcement of the 4'' x 0.5'' silencer base straps is necessary. Basic requirements for this additional support are discussed

  19. Diesel engine exhaust particulate filter with intake throttling incineration control

    Energy Technology Data Exchange (ETDEWEB)

    Ludecke, O.; Rosebrock, T.

    1980-07-08

    A description is given of a diesel engine exhaust filter and particulate incineration system in combination with a diesel engine having a normally unthrottled air induction system for admitting combustion air to the engine and an exhaust system for carrying off spent combustion products exhausted from the engine, said filter and incineration system comprising: a combustion resistant filter disposed in the exhaust system and operative to collect and retain portions of the largely carbonaceous particulate matter contained in the engine exhaust products, said fiber being capable of withstanding without substantial damage internal temperatures sufficient to burn the collected particulate matter, a throttle in the indication system and operable to restrict air flow into the engine to reduce the admittance of excess combustion air and thereby increase engine exhaust gas temperature, and means to actuate said throttle periodically during engine operation to an air flow restricting burn mode capable of raising the particulates in said filter to their combustion temperature under certain engine operating conditions and to maintain said throttle mode for an interval adequate to burn retained particulates in the filter.

  20. Impact of freeway weaving segment design on light-duty vehicle exhaust emissions.

    Science.gov (United States)

    Li, Qing; Qiao, Fengxiang; Yu, Lei; Chen, Shuyan; Li, Tiezhu

    2018-06-01

    In the United States, 26% of greenhouse gas emissions is emitted from the transportation sector; these emisssions meanwhile are accompanied by enormous toxic emissions to humans, such as carbon monoxide (CO), nitrogen oxides (NO x ), and hydrocarbon (HC), approximately 2.5% and 2.44% of a total exhaust emissions for a petrol and a diesel engine, respectively. These exhaust emissions are typically subject to vehicles' intermittent operations, such as hard acceleration and hard braking. In practice, drivers are inclined to operate intermittently while driving through a weaving segment, due to complex vehicle maneuvering for weaving. As a result, the exhaust emissions within a weaving segment ought to vary from those on a basic segment. However, existing emission models usually rely on vehicle operation information, and compute a generalized emission result, regardless of road configuration. This research proposes to explore the impacts of weaving segment configuration on vehicle emissions, identify important predictors for emission estimations, and develop a nonlinear normalized emission factor (NEF) model for weaving segments. An on-board emission test was conducted on 12 subjects on State Highway 288 in Houston, Texas. Vehicles' activity information, road conditions, and real-time exhaust emissions were collected by on-board diagnosis (OBD), a smartphone-based roughness app, and a portable emission measurement system (PEMS), respectively. Five feature selection algorithms were used to identify the important predictors for the response of NEF and the modeling algorithm. The predictive power of four algorithm-based emission models was tested by 10-fold cross-validation. Results showed that emissions are also susceptible to the type and length of a weaving segment. Bagged decision tree algorithm was chosen to develop a 50-grown-tree NEF model, which provided a validation error of 0.0051. The estimated NEFs are highly correlated with the observed NEFs in the training

  1. Work-family conflict, emotional exhaustion and performance-based self-esteem: reciprocal relationships.

    Science.gov (United States)

    Richter, Anne; Schraml, Karin; Leineweber, Constanze

    2015-01-01

    The three constructs of work-family conflict, emotional exhaustion and performance-based self-esteem are all related to tremendous negative consequences for the individual, the organization as well as for society. Even though there are studies that connect two of those constructs, the prospective relations between all three of them have not been studied yet. We explored the prospective relations between the three constructs in a large Swedish data set representative of the Swedish workforce. Gender differences in the relations were investigated. Longitudinal data with a 2-year time lag were gathered from 3,387 working men and women who responded to the 2006 and 2008 waves of the Swedish Longitudinal Occupational Survey of Health. Four different cross-lagged models were analysed. In the best fitting model, higher levels of work-family conflict at time 1 were associated with an increased level of performance-based self-esteem at time 2, but not with emotional exhaustion, after controlling for having children, gender, education and age. Also, relationships between emotional exhaustion at time 1 and work-family conflict and performance-based self-esteem at time 2 could be established. Furthermore, relationships between performance-based self-esteem time 1 and work-family conflict and emotional exhaustion time 2 were found. Multiple-group analysis did not show any differences in the relations of the tested constructs over time for either men or women. We conclude that the three constructs are interrelated and best understood through a reciprocal model. No differences were found between men and women.

  2. 40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.

    Science.gov (United States)

    2010-07-01

    ... exhaust duct excludes the length of pipe representative of the vehicle exhaust pipe) shall be minimized... exhaust manifold, immediately after exhaust aftertreatment systems, or after a length of pipe representative of the vehicle exhaust pipe; or (iv) Partial dilution of the exhaust gas prior to entering the...

  3. Exhaust energy conversion by thermoelectric generator: Two case studies

    International Nuclear Information System (INIS)

    Karri, M.A.; Thacher, E.F.; Helenbrook, B.T.

    2011-01-01

    This study reports predictions of the power and fuel savings produced by thermoelectric generators (TEG) placed in the exhaust stream of a sports utility vehicle (SUV) and a stationary, compressed-natural-gas-fueled engine generator set (CNG). Results are obtained for generators using either commercially-available bismuth telluride (Bi 2 Te 3 ) or quantum-well (QW) thermoelectric material. The simulated tests are at constant speed in the SUV case and at constant AC power load in the CNG case. The simulations make use of the capabilities of ADVISOR 2002, the vehicle modeling system, supplemented with code to describe the thermoelectric generator system. The increase in power between the QW- and Bi 2 Te 3 -based generators was about three times for the SUV and seven times for the CNG generator under the same simulation conditions. The relative fuel savings for the SUV averaged around -0.2% using Bi 2 Te 3 and 1.25% using QW generators. For the CNG case the fuel savings was around 0.4% using Bi 2 Te 3 and around 3% using QW generators. The negative fuel gains in the SUV were caused by parasitic losses. The power to transport the TEG system weight was the dominant parasitic loss for the SUV but was absent in the CNG generator. The lack of space constraint and the absence of parasitic loss from the TEG system weight in the CNG case allowed an increase in the TEG system size to generate more power.

  4. Removal of methane from compressed natural gas fueled vehicle exhaust

    International Nuclear Information System (INIS)

    Subramanian, S.; Kudla, R.J.; Chattha, M.S.

    1992-01-01

    The objective of this paper is to investigate the modes of methane (CH 4 ) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the oxidation of methane with oxygen as well as nitric oxide contributes to its removal under net reducing conditions. The steam reforming reaction does not significantly contribute to the removal of methane. The methane conversions under net reducing conditions are higher than those observed under net oxidizing conditions. The study shows that the presence of carbon monoxide in the feed gas leads to a gradual decrease in the methane conversion with increasing redox ratio, under net oxidizing conditions. a minimum in methane conversion is observed at a redox ratio of 0. 8. The higher activity for the methane-oxygen reaction resulting from a lowering in the overall oxidation state of palladium and the contribution of the methane-nitric oxide reaction toward the removal of CH 4 appear to account for the higher CH 4 conversions observed under net reducing conditions

  5. Investigation of Cooling Water Injection into Supersonic Rocket Engine Exhaust

    Science.gov (United States)

    Jones, Hansen; Jeansonne, Christopher; Menon, Shyam

    2017-11-01

    Water spray cooling of the exhaust plume from a rocket undergoing static testing is critical in preventing thermal wear of the test stand structure, and suppressing the acoustic noise signature. A scaled test facility has been developed that utilizes non-intrusive diagnostic techniques including Focusing Color Schlieren (FCS) and Phase Doppler Particle Anemometry (PDPA) to examine the interaction of a pressure-fed water jet with a supersonic flow of compressed air. FCS is used to visually assess the interaction of the water jet with the strong density gradients in the supersonic air flow. PDPA is used in conjunction to gain statistical information regarding water droplet size and velocity as the jet is broken up. Measurement results, along with numerical simulations and jet penetration models are used to explain the observed phenomena. Following the cold flow testing campaign a scaled hybrid rocket engine will be constructed to continue tests in a combusting flow environment similar to that generated by the rocket engines tested at NASA facilities. LaSPACE.

  6. Quality of clinical supervision and counselor emotional exhaustion: the potential mediating roles of organizational and occupational commitment.

    Science.gov (United States)

    Knudsen, Hannah K; Roman, Paul M; Abraham, Amanda J

    2013-01-01

    Counselor emotional exhaustion has negative implications for treatment organizations as well as the health of counselors. Quality clinical supervision is protective against emotional exhaustion, but research on the mediating mechanisms between supervision and exhaustion is limited. Drawing upon data from 934 counselors affiliated with treatment programs in the National Institute on Drug Abuse's Clinical Trials Network (CTN), this study examined commitment to the treatment organization and commitment to the counseling occupation as potential mediators of the relationship between quality clinical supervision and emotional exhaustion. The final ordinary least squares (OLS) regression model, which accounted for the nesting of counselors within treatment organizations, indicated that these two types of commitment were plausible mediators of the association between clinical supervision and exhaustion. Higher quality clinical supervision was strongly correlated with commitment to the treatment organization as well as commitment to the occupation of SUD counseling. These findings suggest that quality clinical supervision has the potential to yield important benefits for counselor well-being by strengthening ties to both their employing organization as well the larger treatment field, but longitudinal research is needed to establish these causal relationships. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Blimp-1–mediated CD4 T cell exhaustion causes CD8 T cell dysfunction during chronic toxoplasmosis

    Science.gov (United States)

    Cobb, Dustin A.; Bhadra, Rajarshi

    2016-01-01

    CD8, but not CD4, T cells are considered critical for control of chronic toxoplasmosis. Although CD8 exhaustion has been previously reported in Toxoplasma encephalitis (TE)–susceptible model, our current work demonstrates that CD4 not only become exhausted during chronic toxoplasmosis but this dysfunction is more pronounced than CD8 T cells. Exhausted CD4 population expressed elevated levels of multiple inhibitory receptors concomitant with the reduced functionality and up-regulation of Blimp-1, a transcription factor. Our data demonstrates for the first time that Blimp-1 is a critical regulator for CD4 T cell exhaustion especially in the CD4 central memory cell subset. Using a tamoxifen-dependent conditional Blimp-1 knockout mixed bone marrow chimera as well as an adoptive transfer approach, we show that CD4 T cell–intrinsic deletion of Blimp-1 reversed CD8 T cell dysfunction and resulted in improved pathogen control. To the best of our knowledge, this is a novel finding, which demonstrates the role of Blimp-1 as a critical regulator of CD4 dysfunction and links it to the CD8 T cell dysfunctionality observed in infected mice. The critical role of CD4-intrinsic Blimp-1 expression in mediating CD4 and CD8 T cell exhaustion may provide a rational basis for designing novel therapeutic approaches. PMID:27481131

  8. Effect of aircraft exhaust sulfur emissions on near field plume aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Miake-Lye, R.C.; Anderson, M.R.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics

    1997-12-31

    Based on estimated exit plane sulfur speciation, a two dimensional, axisymmetric flow field model with coupled gas phase oxidation kinetics and aerosol nucleation and growth dynamics is used to evaluate the effect of fuel sulfur oxidation in the engine on the formation and growth of volatile H{sub 2}SO{sub 4}/H{sub 2}O aerosols in the near field plume. The conversion of fuel sulfur to sulfur trioxide and sulfuric acid in the engine is predicted to significantly increase the number density and surface area density of volatile H{sub 2}SO{sub 4}/H{sub 2}O aerosols and the chemical activation of exhaust soot particulates. This analysis indicates the need for experimental measurements of exhaust SO{sub x} emissions to fully assess the atmospheric impact of aircraft emissions. (author) 18 refs.; Submitted to Geophysical Research Letters

  9. Effect of aircraft exhaust sulfur emissions on near field plume aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R C; Miake-Lye, R C; Anderson, M R; Kolb, C E [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics

    1998-12-31

    Based on estimated exit plane sulfur speciation, a two dimensional, axisymmetric flow field model with coupled gas phase oxidation kinetics and aerosol nucleation and growth dynamics is used to evaluate the effect of fuel sulfur oxidation in the engine on the formation and growth of volatile H{sub 2}SO{sub 4}/H{sub 2}O aerosols in the near field plume. The conversion of fuel sulfur to sulfur trioxide and sulfuric acid in the engine is predicted to significantly increase the number density and surface area density of volatile H{sub 2}SO{sub 4}/H{sub 2}O aerosols and the chemical activation of exhaust soot particulates. This analysis indicates the need for experimental measurements of exhaust SO{sub x} emissions to fully assess the atmospheric impact of aircraft emissions. (author) 18 refs.; Submitted to Geophysical Research Letters

  10. Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

    Directory of Open Access Journals (Sweden)

    Galashov Nikolay

    2017-01-01

    Full Text Available The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG of combined-cycle gas turbine (CCGT. Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion products and the amount of water vapor produced according to a given composition of the burned gas and determine the amount of moisture that will be obtained as a result of condensation at a given temperature of the flue gases at the outlet of the condensation heat exchanger (CHE. To calculate the efficiency of the HRSG taking into account the heat of condensation of moisture in the CHE an equation is derived.

  11. Experimental Study on the Plasma Purification for Diesel Engine Exhaust Gas

    Science.gov (United States)

    Chen, Jing; Zu, Kan; Wang, Mei

    2018-02-01

    It is known that the use of ternary catalysis is capable of significantly reducing the emission of pollutants from petrol vehicles. However, the disadvantages such as the temperature and other limitations make it unsuitable for diesel engines. The plasma-assisted catalyst technology has been applied in dealing with the diesel exhaust in the experiment in order to do further research on the effects of plasma in exhaust processing. The paper not only includes the experimental observation on the change of particle concentration after the operation of purification device, but also builds the kinetic model of chemical reactions to simulate the reactions of nitrogen oxides in plasma through using the software of Matlab, then compares the calculation results with experimental samples and finally gets some useful conclusions in practice.

  12. Effects of particle exhaust on neutral compression ratios in DIII-D

    International Nuclear Information System (INIS)

    Colchin, R.J.; Maingi, R.; Wade, M.R.; Allen, S.L.; Greenfield, C.M.

    1998-08-01

    In this paper, neutral particles in DIII-D are studied via their compression in the plenum and via particle exhaust. The compression of gas in the plena is examined in terms of the magnetic field configuration and wall conditions. DIII-D compression ratios are observed in the range from 1 to ≥ 1,000. Particle control ultimately depends on the exhaust of neutrals via plenum or wall pumping. Wall pumping or outgassing is calculated by means of a detailed particle balance throughout individual discharges, and its effect on particle control is discussed. It is demonstrated that particle control through wall conditioning leads to lower normalized densities. A two-region model shows that the gas compression ratio (C div = divertor plenum neutral pressure/torus neutral pressure) can be interpreted in relation to gas flows in the torus and divertor including the pumping speed of the plenum cryopumps, plasma pumping, and the pumping or outgassing of the walls

  13. Exhaust gas heat recovery through secondary expansion cylinder and water injection in an internal combustion engine

    Directory of Open Access Journals (Sweden)

    Nassiri Toosi Ali

    2017-01-01

    Full Text Available To enhance thermal efficiency and increase performance of an internal combustion engine, a novel concept of coupling a conventional engine with a secondary 4-stroke cylinder and direct water injection process is proposed. The burned gases after working in a traditional 4-stroke combustion cylinder are transferred to a secondary cylinder and expanded even more. After re-compression of the exhaust gases, pre-heated water is injected at top dead center. The evaporation of injected water not only recovers heat from exhaust gases, but also increases the mass of working gas inside the cylinder, therefore improves the overall thermal efficiency. A 0-D/1-D model is used to numerically simulate the idea. The simulations outputs showed that the bottoming cycle will be more efficient at higher engines speeds, specifically in a supercharged/turbocharged engine, which have higher exhaust gas pressure that can reproduce more positive work. In the modeled supercharged engine, results showed that brake thermal efficiency can be improved by about 17%, and brake power by about 17.4%.

  14. An analytical study on the performance of the organic Rankine cycle for turbofan engine exhaust heat recovery

    Science.gov (United States)

    Saadon, S.; Abu Talib, A. R.

    2016-10-01

    Due to energy shortage and global warming, issues of energy saving have become more important. To increase the energy efficiency and reduce the fuel consumption, waste heat recovery is a significant method for energy saving. The organic Rankine cycle (ORC) has great potential to recover the waste heat from the core jet exhaust of a turbofan engine and use it to produce power. Preliminary study of the design concept and thermodynamic performance of this ORC system would assist researchers to predict the benefits of using the ORC system to extract the exhaust heat engine. In addition, a mathematical model of the heat transfer of this ORC system is studied and developed. The results show that with the increment of exhaust heat temperature, the mass flow rate of the working fluid, net power output and the system thermal efficiency will also increase. Consequently, total consumption of jet fuel could be significantly saved as well.

  15. Power Output Stability Research for Harvesting Automobile Exhaust Energy with Heat Capacity Material as Intermediate Medium

    Science.gov (United States)

    Xiao, Longjie; He, Tianming; Mei, Binyu; Wang, Yiping; Wang, Zongsong; Tan, Gangfeng

    2018-06-01

    Automobile exhaust energy thermoelectric utilization can promote energy-saving and emission-reduction. Unexpected urban traffic conditions lead to the hot-end temperature instability of the exhaust pipe-mounted thermoelectric generator (TEG), and influence the TEG power generation efficiency. The heat conduction oil circulation located at the hot-end could smooth the temperature fluctuation, at the expense of larger system size and additional energy supply. This research improves the TEG hot-end temperature stability by installing solid heat capacity material (SHCM) to the area between the outer wall of the exhaust pipe and the TEG, which has the merits of simple structure, light weight and no additional energy consumption. The exhaust temperature and flow rate characteristics with various driving conditions are firstly studied for the target engine. Then the convective heat transfer models of SHCM's hot-end and thermoelectric material's cold-end are established. Meanwhile, SHCM thermal properties' effects on the amplitude and response speed of the TEG hot-end temperature are studied. The candidate SHCM with the characteristics of low thermal resistance and high heat capacity is determined. And the heat transfer model going through from TEG's hot-end to the cold-end is established. The results show that the SHCM significantly improves the TEG hot-end temperature stability but slightly reduces the average power output. When the engine working conditions change a lot, the SHCM's improvement on the TEG hot-end temperature stability is more significant, but the reduction of the average power output becomes more remarkable.

  16. Comparison of aldehyde emissions simulation with FTIR measurements in the exhaust of a spark ignition engine fueled by ethanol

    Science.gov (United States)

    Zarante, Paola Helena Barros; Sodré, José Ricardo

    2018-02-01

    This work presents a numerical simulation model for aldehyde formation and exhaust emissions from ethanol-fueled spark ignition engines. The aldehyde simulation model was developed using FORTRAN software, with the input data obtained from the dedicated engine cycle simulation software AVL BOOST. The model calculates formaldehyde and acetaldehyde concentrations from post-flame partial oxidation of methane, ethane and unburned ethanol. The calculated values were compared with experimental data obtained from a mid-size sedan powered by a 1.4-l spark ignition engine, tested on a chassis dynamometer. Exhaust aldehyde concentrations were determined using a Fourier Transform Infrared (FTIR) Spectroscopy analyzer. In general, the results demonstrate that the concentrations of aldehydes and the source elements increased with engine speed and exhaust gas temperature. The measured acetaldehyde concentrations showed values from 3 to 6 times higher than formaldehyde in the range studied. The model could predict reasonably well the qualitative experimental trends, with the quantitative results showing a maximum discrepancy of 39% for acetaldehyde concentration and 21 ppm for exhaust formaldehyde.

  17. Diffuser Optimation at Exhaust System with Catalytic Converter for 110 cc Mopet with Fluid Flow CFD Simulation

    Directory of Open Access Journals (Sweden)

    Tresna Soemardi

    2010-10-01

    Full Text Available CFD simulation used to get behavior of exhaust gas through catalyst, this result will be used to optimize geometry form to perform uniform stream distribution to catalyst, and CFD Simulation will used to analyze backpressure that happened at the model.

  18. The Mediating Effect of Organizational Trust on the Link between the Areas of Work Life and Emotional Exhaustion

    Science.gov (United States)

    Bayhan Karapinar, Pinar; Metin Camgoz, Selin; Tayfur Ekmekci, Ozge

    2016-01-01

    The study tests an integrative model that considers the plausible effects of different areas of work life on emotional exhaustion. It also tests the mediating effect of organizational trust on this relationship. More specifically, while perceived incongruence in six areas of work life (workload, fairness, reward, community, control and value) is…

  19. Sustainability and Substitution of Exhaustible Natural Resources : How Resource Prices Affect Long-Term R&D Investments

    NARCIS (Netherlands)

    Bretschger, L.; Smulders, J.A.

    2003-01-01

    Traditional resource economics has been criticised for assuming too high elasticities of substitution, not observing material balance principles and relying too much on planner solutions to obtain long-term growth.By analysing a multi-sector R&D based endogenous growth model with exhaustible natural

  20. Automated magnetic divertor design for optimal power exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Blommaert, Maarten

    2017-07-01

    The so-called divertor is the standard particle and power exhaust system of nuclear fusion tokamaks. In essence, the magnetic configuration hereby 'diverts' the plasma to a specific divertor structure. The design of this divertor is still a key issue to be resolved to evolve from experimental fusion tokamaks to commercial power plants. The focus of this dissertation is on one particular design requirement: avoiding excessive heat loads on the divertor structure. The divertor design process is assisted by plasma edge transport codes that simulate the plasma and neutral particle transport in the edge of the reactor. These codes are computationally extremely demanding, not in the least due to the complex collisional processes between plasma and neutrals that lead to strong radiation sinks and macroscopic heat convection near the vessel walls. One way of improving the heat exhaust is by modifying the magnetic confinement that governs the plasma flow. In this dissertation, automated design of the magnetic configuration is pursued using adjoint based optimization methods. A simple and fast perturbation model is used to compute the magnetic field in the vacuum vessel. A stable optimal design method of the nested type is then elaborated that strictly accounts for several nonlinear design constraints and code limitations. Using appropriate cost function definitions, the heat is spread more uniformly over the high-heat load plasma-facing components in a practical design example. Furthermore, practical in-parts adjoint sensitivity calculations are presented that provide a way to an efficient optimization procedure. Results are elaborated for a fictituous JET (Joint European Torus) case. The heat load is strongly reduced by exploiting an expansion of the magnetic flux towards the solid divertor structure. Subsequently, shortcomings of the perturbation model for magnetic field calculations are discussed in comparison to a free boundary equilibrium (FBE) simulation

  1. Automated magnetic divertor design for optimal power exhaust

    International Nuclear Information System (INIS)

    Blommaert, Maarten

    2017-01-01

    The so-called divertor is the standard particle and power exhaust system of nuclear fusion tokamaks. In essence, the magnetic configuration hereby 'diverts' the plasma to a specific divertor structure. The design of this divertor is still a key issue to be resolved to evolve from experimental fusion tokamaks to commercial power plants. The focus of this dissertation is on one particular design requirement: avoiding excessive heat loads on the divertor structure. The divertor design process is assisted by plasma edge transport codes that simulate the plasma and neutral particle transport in the edge of the reactor. These codes are computationally extremely demanding, not in the least due to the complex collisional processes between plasma and neutrals that lead to strong radiation sinks and macroscopic heat convection near the vessel walls. One way of improving the heat exhaust is by modifying the magnetic confinement that governs the plasma flow. In this dissertation, automated design of the magnetic configuration is pursued using adjoint based optimization methods. A simple and fast perturbation model is used to compute the magnetic field in the vacuum vessel. A stable optimal design method of the nested type is then elaborated that strictly accounts for several nonlinear design constraints and code limitations. Using appropriate cost function definitions, the heat is spread more uniformly over the high-heat load plasma-facing components in a practical design example. Furthermore, practical in-parts adjoint sensitivity calculations are presented that provide a way to an efficient optimization procedure. Results are elaborated for a fictituous JET (Joint European Torus) case. The heat load is strongly reduced by exploiting an expansion of the magnetic flux towards the solid divertor structure. Subsequently, shortcomings of the perturbation model for magnetic field calculations are discussed in comparison to a free boundary equilibrium (FBE) simulation. These flaws

  2. Trace elements in particles of motor vehicle exhaust in Shanghai

    International Nuclear Information System (INIS)

    Jiang Da; Qiu Zhijun; Lu Rongrong; Qiu Huiyuan; Zhu Jieqing; Li Xiaolin

    2002-01-01

    A nuclear microprobe with high spatial resolution and high analytical sensitivity was applied to analyze trace elements, especially lead, in vehicle exhaust of Shanghai city. The result shows that the chemical composition and its corresponding x-ray relative intensity are different among different vehicle exhausts. There are many kinds of metal elements in particles of vehicle exhaust, most are harmful to people, such as Ti, Cr, Mn, Pb, etc. The authors found that the lead concentration was 6820 μg/g and the bromine concentration was 5300 μg/g in the exhaust from Santana using leaded gasoline (SULG), which is higher than any other kinds of vehicle exhausts. The authors have also detected the minimum lead in the particles of unleaded gasoline and its content varies from one to another. Its mean concentration was 450 μg/g and the highest reached 6210 μg/g. The unleaded gasoline's Pb existed in the whole particle while the leaded gasoline's enriched in the surface of the particle and was more harmful to the human beings

  3. Variation of particle exhaust with changes in divertor magnetic balance

    International Nuclear Information System (INIS)

    Petrie, T.W.; Allen, S.L.; Brooks, N.H.

    2006-01-01

    Recent experiments on DIII-D point to the importance of two factors in determining how effectively the deuterium particle inventory in a tokamak plasma can be controlled through pumping at the divertor target(s): (1) the divertor magnetic balance, i.e. the degree to which the divertor topology is single-null or double-null (DN) and (2) the direction of the of B x ∇B ion drift with respect to the X-point(s). Changes in divertor magnetic balance near the DN shape have a much stronger effect on the particle exhaust rate at the inner divertor target(s) than on the particle exhaust rate at the outer divertor target(s). The particle exhaust rate for the DN shape is strongest at the outer strike point opposite the B x ∇B ion particle drift direction. Our data suggests that the presence of B x ∇B and E x B ion particle drifts in the scrape-off layer and divertor(s) play an important role in the particle exhaust rates of DN and near-DN plasmas. Particle exhaust rates are shown to depend strongly on the edge (pedestal) density. These results have implications for particle control in ITER and other future tokamaks

  4. Design and experimental study on desulphurization process of ship exhaust

    Science.gov (United States)

    Han, Mingyang; Hao, Shan; Zhou, Junbo; Gao, Liping

    2018-02-01

    This desulfurization process involves removing sulfur oxides with seawater or alkaline aqueous solutions and then treating the effluent by aeration and pH adjustment before discharging it into the ocean. In the desulfurization system, the spray tower is the key equipment and the venturi tubes are the pretreatment device. The two stages of plates are designed to fully absorb sulfur oxides in exhaust gases. The spiral nozzles atomize and evenly spray the desulfurizers into the tower. This study experimentally investigated the effectiveness of this desulfurization process and the factors influencing it under laboratory conditions, with a diesel engine exhaust used to represent ship exhaust. The experimental results show that this process can effectively absorb the SO2 in the exhaust. When the exhaust flow rate was 25 m3/h and the desulfurizer flow rate was 4 L/min, the sulfur removal efficiency (SRE) reached 99.7%. The flow rate, alkalinity, and temperature of seawater were found to have significant effects on the SRE. Adjusting seawater flow rate (SWR) and alkalinity within certain ranges can substantially improve the SRE.

  5. Non-exhaust PM emissions from electric vehicles

    Science.gov (United States)

    Timmers, Victor R. J. H.; Achten, Peter A. J.

    2016-06-01

    Particulate matter (PM) exposure has been linked to adverse health effects by numerous studies. Therefore, governments have been heavily incentivising the market to switch to electric passenger cars in order to reduce air pollution. However, this literature review suggests that electric vehicles may not reduce levels of PM as much as expected, because of their relatively high weight. By analysing the existing literature on non-exhaust emissions of different vehicle categories, this review found that there is a positive relationship between weight and non-exhaust PM emission factors. In addition, electric vehicles (EVs) were found to be 24% heavier than equivalent internal combustion engine vehicles (ICEVs). As a result, total PM10 emissions from EVs were found to be equal to those of modern ICEVs. PM2.5 emissions were only 1-3% lower for EVs compared to modern ICEVs. Therefore, it could be concluded that the increased popularity of electric vehicles will likely not have a great effect on PM levels. Non-exhaust emissions already account for over 90% of PM10 and 85% of PM2.5 emissions from traffic. These proportions will continue to increase as exhaust standards improve and average vehicle weight increases. Future policy should consequently focus on setting standards for non-exhaust emissions and encouraging weight reduction of all vehicles to significantly reduce PM emissions from traffic.

  6. Acceptance test report for portable exhauster POR-008/Skid F

    International Nuclear Information System (INIS)

    Kriskovich, J.R.

    1998-01-01

    Portable Exhauster POR-008 was procured via HNF-0490, Specification for a Portable Exhausted System for Waste Tank Ventilation. Prior to taking ownership, acceptance testing was performed at the vendors. However at the conclusion of testing a number of issues remained that required resolution before the exhausters could be used by Project W-320. The purpose of acceptance testing documented by this report was to demonstrate compliance of the exhausters with the performance criteria established within HNF-O49O, Rev. 1 following a repair and upgrade effort at Hanford. In addition, data obtained during this testing is required for the resolution of outstanding Non-conformance Reports (NCR), and finally, to demonstrate the functionality of the associated software for the pressure control and high vacuum exhauster operating modes provided for by W-320. Additional testing not required by the ATP was also performed to assist in the disposition and close out of receiving inspection report and for application design information (system curve). Results of this testing are also captured within this document

  7. Vacuum exhaustion system for thermonuclear reactor and cryopump thereof

    International Nuclear Information System (INIS)

    Kobayashi, Shigetada.

    1992-01-01

    An impurity removing device is connected to a gas exhaust side of a plasma vacuum vessel by way of a gate valve, a cryopump is connected to the exit side of the device by way of an exit valve, a fuel transfer line is disposed for transferring fuels to a fuel purification system and a vacuum pump line is disposed to an exhaust gas line. Further, a tritium monitor is disposed to an exhaustion line and the line on the side of the exit of the monitor is branched into two ways, in which a tritium transfer pipe is disposed to one of them and an atmosphere release pipe is disposed on the other of them by way of an atmosphere releasing valve. Further, a condensation shebron is disposed for flowing in and out fuel isotope gases discharged from the plasma vacuum vessel, and a funnel discharge pipe is disposed for discharging a liquefied and condensed fluid. Since the gases to be exhausted are liquefied and condensed without coagulation or coagulation products are removed while operating the pump, the exhaust gases are processed continuously to reduce tritium inventory and make the regeneration step unnecessary and remarkably improve the heat efficiency. (N.H.)

  8. Effect of Pellet Boiler Exhaust on Secondary Organic Aerosol Formation from α-Pinene.

    Science.gov (United States)

    Kari, Eetu; Hao, Liqing; Yli-Pirilä, Pasi; Leskinen, Ari; Kortelainen, Miika; Grigonyte, Julija; Worsnop, Douglas R; Jokiniemi, Jorma; Sippula, Olli; Faiola, Celia L; Virtanen, Annele

    2017-02-07

    Interactions between anthropogenic and biogenic emissions, and implications for aerosol production, have raised particular scientific interest. Despite active research in this area, real anthropogenic emission sources have not been exploited for anthropogenic-biogenic interaction studies until now. This work examines these interactions using α-pinene and pellet boiler emissions as a model test system. The impact of pellet boiler emissions on secondary organic aerosol (SOA) formation from α-pinene photo-oxidation was studied under atmospherically relevant conditions in an environmental chamber. The aim of this study was to identify which of the major pellet exhaust components (including high nitrogen oxide (NO x ), primary particles, or a combination of the two) affected SOA formation from α-pinene. Results demonstrated that high NO x concentrations emitted by the pellet boiler reduced SOA yields from α-pinene, whereas the chemical properties of the primary particles emitted by the pellet boiler had no effect on observed SOA yields. The maximum SOA yield of α-pinene in the presence of pellet boiler exhaust (under high-NO x conditions) was 18.7% and in the absence of pellet boiler exhaust (under low-NO x conditions) was 34.1%. The reduced SOA yield under high-NO x conditions was caused by changes in gas-phase chemistry that led to the formation of organonitrate compounds.

  9. Toxicity of aged gasoline exhaust particles to normal and diseased airway epithelia.

    Science.gov (United States)

    Künzi, Lisa; Krapf, Manuel; Daher, Nancy; Dommen, Josef; Jeannet, Natalie; Schneider, Sarah; Platt, Stephen; Slowik, Jay G; Baumlin, Nathalie; Salathe, Matthias; Prévôt, André S H; Kalberer, Markus; Strähl, Christof; Dümbgen, Lutz; Sioutas, Constantinos; Baltensperger, Urs; Geiser, Marianne

    2015-06-29

    Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment system varying particle number concentration independent of particle chemistry, and an aerosol deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics-treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully-differentiated HBE is most appropriate in future toxicity studies.

  10. Study on the Noise Reduction of Vehicle Exhaust NOX Spectra Based on Adaptive EEMD Algorithm

    Directory of Open Access Journals (Sweden)

    Kai Zhang

    2017-01-01

    Full Text Available It becomes a key technology to measure the concentration of the vehicle exhaust components with the transmission spectra. But in the conventional methods for noise reduction and baseline correction, such as wavelet transform, derivative, interpolation, polynomial fitting, and so forth, the basic functions of these algorithms, the number of decomposition layers, and the way to reconstruct the signal have to be adjusted according to the characteristics of different components in the transmission spectra. The parameter settings of the algorithms above are not transcendental, so with them, it is difficult to achieve the best noise reduction effect for the vehicle exhaust spectra which are sharp and drastic in the waveform. In this paper, an adaptive ensemble empirical mode decomposition (EEMD denoising model based on a special normalized index optimization is proposed and used in the spectral noise reduction of vehicle exhaust NOX. It is shown with the experimental results that the method can effectively improve the accuracy of the spectral noise reduction and simplify the denoising process and its operation difficulty.

  11. Removal of lead and fluoride from contaminated water using exhausted coffee grounds based bio-sorbent.

    Science.gov (United States)

    Naga Babu, A; Reddy, D Srinivasa; Kumar, G Suresh; Ravindhranath, K; Krishna Mohan, G V

    2018-07-15

    Water pollution by industrial and anthropogenic actives has become a serious threat to the environment. World Health Organization (WHO) has identified that lead and fluoride amid the environmental pollutants are most poisonous water contaminants with devastating impact on the human race. The present work proposes a study on economical bio-adsorbent based technique using exhausted coffee grounds in the removal of lead and fluoride contaminants from water. The exhausted coffee grounds gathered from industrial wastes have been acid-activated and examined for their adsorption capacity. The surface morphology and elemental characterization of pre-and-post adsorption operations by FESEM, EDX and FTIR spectral analysis confirmed the potential of the exhausted coffee ground as successful bio-sorbent. However, thermodynamic analysis confirmed the adsorption to be spontaneous physisorption with Langmuir mode of homogenous monolayer deposition. The kinetics of adsorption is well defined by pseudo second order model for both lead and fluoride. A significant quantity of lead and fluoride is removed from the synthetic contaminated water by the proposed bio-sorbent with the respective sorption capabilities of 61.6 mg/g and 9.05 mg/g. However, the developed bio-sorbent is also recyclable and is capable of removing the lead and fluoride from the domestic and industrial waste-water sources with an overall removal efficiency of about 90%. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Toxicity of aged gasoline exhaust particles to normal and diseased airway epithelia

    Science.gov (United States)

    Künzi, Lisa; Krapf, Manuel; Daher, Nancy; Dommen, Josef; Jeannet, Natalie; Schneider, Sarah; Platt, Stephen; Slowik, Jay G.; Baumlin, Nathalie; Salathe, Matthias; Prévôt, André S. H.; Kalberer, Markus; Strähl, Christof; Dümbgen, Lutz; Sioutas, Constantinos; Baltensperger, Urs; Geiser, Marianne

    2015-06-01

    Particulate matter (PM) pollution is a leading cause of premature death, particularly in those with pre-existing lung disease. A causative link between particle properties and adverse health effects remains unestablished mainly due to complex and variable physico-chemical PM parameters. Controlled laboratory experiments are required. Generating atmospherically realistic aerosols and performing cell-exposure studies at relevant particle-doses are challenging. Here we examine gasoline-exhaust particle toxicity from a Euro-5 passenger car in a uniquely realistic exposure scenario, combining a smog chamber simulating atmospheric ageing, an aerosol enrichment system varying particle number concentration independent of particle chemistry, and an aerosol deposition chamber physiologically delivering particles on air-liquid interface (ALI) cultures reproducing normal and susceptible health status. Gasoline-exhaust is an important PM source with largely unknown health effects. We investigated acute responses of fully-differentiated normal, distressed (antibiotics-treated) normal, and cystic fibrosis human bronchial epithelia (HBE), and a proliferating, single-cell type bronchial epithelial cell-line (BEAS-2B). We show that a single, short-term exposure to realistic doses of atmospherically-aged gasoline-exhaust particles impairs epithelial key-defence mechanisms, rendering it more vulnerable to subsequent hazards. We establish dose-response curves at realistic particle-concentration levels. Significant differences between cell models suggest the use of fully-differentiated HBE is most appropriate in future toxicity studies.

  13. Analysis of heat recovery from a spray dryer by recirculation of exhaust air

    International Nuclear Information System (INIS)

    Golman, Boris; Julklang, Wittaya

    2014-01-01

    Highlights: • We study a spray dryer with heat recovery by partial recirculation of exhaust air. • We examine effects of process parameters on energy efficiency and energy savings. • Decreasing drying air temperature and flow rate will increase energy efficiency. • Increasing recirculation ratio and slurry feed rate will increase energy efficiency. - Abstract: Model simulations were employed to investigate the influences of process parameters on the energy recovery in spray drying process that partially recycle the exhaust drying gas. The energy efficiency and energy saving were studied for various values of recirculation ratios with respect to the temperature and flow rate of the drying air, slurry feed rate and concentration of slurry in spray drying of advanced ceramic materials. As a result, significant gains in energy efficiency and energy saving were obtained for a spray drying system with high recirculation ratio of exhaust air. The high slurry feed rate and the low slurry concentration, inlet drying air temperature and drying air flow rate enhanced the energy efficiency of spray drying system. However, the high energy saving was obtained in spray dryers operating at low slurry feed rate and high slurry concentration

  14. Numerical and experimental analysis for exhaust heat exchangers in automobile thermoelectric generators

    Directory of Open Access Journals (Sweden)

    Shengqiang Bai

    2014-11-01

    Full Text Available Ideal heat exchangers recover as much heat as possible from an engine exhaust at the cost of an acceptable pressure drop. They provide primary heat for a thermoelectric generator (TEG, and their capacity and efficiency is dependent on the material, shape, and type of the heat exchanger. Six different exhaust heat exchangers were designed within the same shell, and their computational fluid dynamics (CFD models were developed to compare heat transfer and pressure drop in typical driving cycles for a vehicle with a 1.2 L gasoline engine. The result showed that the serial plate structure enhanced heat transfer by 7 baffles and transferred the maximum heat of 1737 W. It also produced a maximum pressure drop of 9.7 kPa in a suburban driving cycle. The numerical results for the pipe structure and an empty cavity were verified by experiments. Under the maximum power output condition, only the inclined plate and empty cavity structure undergoes a pressure drop less than 80 kPa, and the largest pressure drop exceeds 190 kPa. In this case, a mechanism with a differential pressure switch is essential to bypass part of the exhaust.

  15. The relationship between baseline Organizational Readiness to Change Assessment subscale scores and implementation of hepatitis prevention services in substance use disorders treatment clinics: a case study

    Directory of Open Access Journals (Sweden)

    Hagedorn Hildi J

    2010-06-01

    Full Text Available Abstract Background The Organizational Readiness to Change Assessment (ORCA is a measure of organizational readiness for implementing practice change in healthcare settings that is organized based on the core elements and sub-elements of the Promoting Action on Research Implementation in Health Services (PARIHS framework. General support for the reliability and factor structure of the ORCA has been reported. However, no published study has examined the utility of the ORCA in a clinical setting. The purpose of the current study was to examine the relationship between baseline ORCA scores and implementation of hepatitis prevention services in substance use disorders (SUD clinics. Methods Nine clinic teams from Veterans Health Administration SUD clinics across the United States participated in a six-month training program to promote evidence-based practices for hepatitis prevention. A representative from each team completed the ORCA evidence and context subscales at baseline. Results Eight of nine clinics reported implementation of at least one new hepatitis prevention practice after completing the six-month training program. Clinic teams were categorized by level of implementation-high (n = 4 versus low (n = 5-based on how many hepatitis prevention practices were integrated into their clinics after completing the training program. High implementation teams had significantly higher scores on the patient experience and leadership culture subscales of the ORCA compared to low implementation teams. While not reaching significance in this small sample, high implementation clinics also had higher scores on the research, clinical experience, staff culture, leadership behavior, and measurement subscales as compared to low implementation clinics. Conclusions The results of this study suggest that the ORCA was able to measure differences in organizational factors at baseline between clinics that reported high and low implementation of practice

  16. Evaluation of the Correlations between Depression, Anxiety, and Stress as DASS-21 Subscales and High-Risk Behaviors in the Adolescents in Torghabeh and Shandiz Towns, Iran

    Directory of Open Access Journals (Sweden)

    Emadodin Darchini-Maragheh

    2017-07-01

    Full Text Available Introduction: Adolescence is a critical period in life, which is associated with tumultuous transitions and “storm and stress. The present study aimed to evaluate the correlation between depression, anxiety, and stress with the high-risk behaviors among the adolescents in Torghabeh and Shandiz towns, Iran. Materials and Methods: This cross-sectional study was conducted on 90 adolescents from the high schools. Participants were selected via two-stage sampling. Data were collected using the validated Depression, Anxiety, and Stress Scale (DASS-21 and history of high-risk behaviors in the students. Data analysis was performed in SPSS version 16. Results:Variable degrees of depression, anxiety, and stress were reported in 43.3%, 43.3%, and 38.9% of the students, respectively. Although the difference was not statistically significant, female students were more affected by the mentioned disorders compared to the male students. Among the high-risk behaviors, smoking cigarettes was significantly correlated with the depression, anxiety, and stress subscales. In addition, a significant association was observed between opium consumption and stress. However, no significant correlation was observed between smoking hookah and the DASS-21 subscales. Regular alcohol consumption was found to be significantly correlated with the higher rate of depression in the studied adolescents. Also, premarital sexual behaviors had a significant association with the stress and depression subscales. Conclusion: Lack of attention to depression, anxiety, and stress and their risk factors in adolescents may lead to variable degrees of life dissatisfaction in the community. Therefore, it is recommended that on-school mental screening programs be performed for high-school students in order prevent these complications.

  17. Economic analysis of gradual "social exhaustion" of waste management capacity.

    Science.gov (United States)

    Koide, Hideo; Nakayama, Hirofumi

    2013-12-01

    This article proposes to analyze the quantitative effects of a gradual physical and "social" exhaustion of a landfill site on an equilibrium waste management service. A gradual social exhaustion of a landfill is defined here as an upward shift of a "subjective factor" associated with the amount of waste, based on the plausible hypothesis that an individual will not accept excessive presence of landfilled waste. Physical exhaustion occurs when the absolute capacity of a landfill site decreases. The paper shows some numerical examples using specific functions and parameters, and proposes appropriate directions for three policy objectives: to decrease the equilibrium waste disposal, to increase the economic surplus of the individual and/or the waste management firm, and to lower the equilibrium collection fee. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  18. Schlieren image velocimetry measurements in a rocket engine exhaust plume

    Science.gov (United States)

    Morales, Rudy; Peguero, Julio; Hargather, Michael

    2017-11-01

    Schlieren image velocimetry (SIV) measures velocity fields by tracking the motion of naturally-occurring turbulent flow features in a compressible flow. Here the technique is applied to measuring the exhaust velocity profile of a liquid rocket engine. The SIV measurements presented include discussion of visibility of structures, image pre-processing for structure visibility, and ability to process resulting images using commercial particle image velocimetry (PIV) codes. The small-scale liquid bipropellant rocket engine operates on nitrous oxide and ethanol as propellants. Predictions of the exhaust velocity are obtained through NASA CEA calculations and simple compressible flow relationships, which are compared against the measured SIV profiles. Analysis of shear layer turbulence along the exhaust plume edge is also presented.

  19. Emotional exhaustion and defense mechanisms in intensive therapy unit nurses.

    Science.gov (United States)

    Regan, Anna; Howard, Ruth A; Oyebode, Jan R

    2009-05-01

    Contrary to its original conceptualization, research has found that emotional demands do not lead to burnout in nurses. According to psychoanalytic theory, unconscious defense mechanisms may protect nurses from conscious awareness of work-related anxiety. This prevents self-report and may explain research findings. The maturity of defense style influences how anxiety is managed. Immature defenses prevent the conscious processing necessary for resolution of anxiety. Therefore, it is hypothesized that the use of immature defenses will lead to emotional exhaustion. This cross-sectional study used questionnaires to explore the defense mechanisms of 87 Intensive Therapy Unit nurses. Although the sample endorsed a predominantly mature defense style, the use of immature defenses predicted emotional exhaustion. Also, lower levels of reported stress associated with emotional demands predicted emotional exhaustion. Although this strongly implies the mediating role of immature defense mechanisms, the results were not statistically significant.

  20. Emissions of exhaust gases and health of the person

    Science.gov (United States)

    Germanova, Tatiana; Kernozhitskaya, Anna

    2017-10-01

    The auto-road complex brings the considerable contribution to pollution and adverse change of environment. Influence of exhaust gases of cars is at the bottom of occurrence and developments of various forms of diseases. Every townsman feels the negative influence rendered by motor transport on himself. The modern city dweller is so accustomed to the smell of exhaust gases that he does not even notice it at all, continues to breathe a poisonous mixture, while neither the car nor the road can be isolated from the habitats of people. The higher the population density, the higher the need for motor transport. The health effects of emissions of exhaust gases and vapors, including regulated and unregulated pollutants, are discussed in this article.