WorldWideScience

Sample records for lean burn gas

  1. Stoichiometric and lean burn heavy-duty gas engines: a dilemma between emissions and fuel consumption?

    NARCIS (Netherlands)

    Steen, M. van der; Rijke, J. de; Seppen, J.J.

    1996-01-01

    This paper compares stoichiometric with lean burn technology for heavy-duty gas engines (natural gas and LPG) and demonstrates that there is a future for both engine concepts on the multilateral global market. Emission limits in Europe as expected in the near future will facilitate both engine

  2. Hydrogen Addition for Improved Lean Burn Capability on Natural Gas Engine

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Tobias [Lund Inst. of Technology (Sweden). Dept. of Heat and Power Engineering

    2002-12-01

    Lean burn spark ignition (SI) engines powered by natural gas is an attractive alternative to the Diesel engine, especially in urban traffic, where reduction of tailpipe emissions are of great importance. A major benefit is the large reduction in soot (PM). Lean burn spark ignition (SI) engines yield high fuel conversion efficiency and also relatively low NO{sub x} emissions at full load. In order to improve the engine operating characteristics at lower loads, the {lambda}-value is normally reduced to some degree, with increased NO{sub x} emissions and reduced efficiency as a result. This is a drawback for the lean burn engines, especially in urban applications such as in city buses and distribution trucks for urban use. So, it is desirable to find ways to extend the lean limit at low loads. One way to improve these part load properties is to add hydrogen to the natural gas in order to improve the combustion characteristics of the fuel. It is possible to extend the lean limit of a natural gas engine by addition of hydrogen to the primary fuel. This report presents measurements made on a single cylinder 1.6 liter natural gas engine. Two combustion chambers, one slow and one fast burning, were tested with various amounts of hydrogen (0 to 20 %-vol) added to natural gas. Three operating conditions were investigated for each combustion chamber and each hydrogen content level; idle, wide open throttle (WOT) and a high load condition (simulated turbo charging). For all three operating conditions, the air/fuel ratio was varied between stoichiometric and the lean limit. For each operating point, the ignition timing was swept in order to find maximum brake torque (MBT) timing. In some cases were the ignition timing limited by knock. Heat release rate calculations were made in order to assess the influence of hydrogen addition on burn rate. Addition of hydrogen showed an increase in burn rate for both combustion chambers, resulting in more stable combustion close to the lean

  3. Load compensation in a lean burn natural gas vehicle

    Science.gov (United States)

    Gangopadhyay, Anupam

    A new multivariable PI tuning technique is developed in this research that is primarily developed for regulation purposes. Design guidelines are developed based on closed-loop stability. The new multivariable design is applied in a natural gas vehicle to combine idle and A/F ratio control loops. This results in better recovery during low idle operation of a vehicle under external step torques. A powertrain model of a natural gas engine is developed and validated for steady-state and transient operation. The nonlinear model has three states: engine speed, intake manifold pressure and fuel fraction in the intake manifold. The model includes the effect of fuel partial pressure in the intake manifold filling and emptying dynamics. Due to the inclusion of fuel fraction as a state, fuel flow rate into the cylinders is also accurately modeled. A linear system identification is performed on the nonlinear model. The linear model structure is predicted analytically from the nonlinear model and the coefficients of the predicted transfer function are shown to be functions of key physical parameters in the plant. Simulations of linear system and model parameter identification is shown to converge to the predicted values of the model coefficients. The multivariable controller developed in this research could be designed in an algebraic fashion once the plant model is known. It is thus possible to implement the multivariable PI design in an adaptive fashion combining the controller with identified plant model on-line. This will result in a self-tuning regulator (STR) type controller where the underlying design criteria is the multivariable tuning technique designed in this research.

  4. Selective NOx Recirculation for Stationary Lean-Burn Natural Gas Engines

    Energy Technology Data Exchange (ETDEWEB)

    Nigel N. Clark

    2006-12-31

    Nitric oxide (NO) and nitrogen dioxide (NO2) generated by internal combustion (IC) engines are implicated in adverse environmental and health effects. Even though lean-burn natural gas engines have traditionally emitted lower oxides of nitrogen (NOx) emissions compared to their diesel counterparts, natural gas engines are being further challenged to reduce NOx emissions to 0.1 g/bhp-hr. The Selective NOx Recirculation (SNR) approach for NOx reduction involves cooling the engine exhaust gas and then adsorbing the NOx from the exhaust stream, followed by the periodic desorption of NOx. By sending the desorbed NOx back into the intake and through the engine, a percentage of the NOx can be decomposed during the combustion process. SNR technology has the support of the Department of Energy (DOE), under the Advanced Reciprocating Engine Systems (ARES) program to reduce NOx emissions to under 0.1 g/bhp-hr from stationary natural gas engines by 2010. The NO decomposition phenomenon was studied using two Cummins L10G natural gas fueled spark-ignited (SI) engines in three experimental campaigns. It was observed that the air/fuel ratio ({lambda}), injected NO quantity, added exhaust gas recirculation (EGR) percentage, and engine operating points affected NOx decomposition rates within the engine. Chemical kinetic model predictions using the software package CHEMKIN were performed to relate the experimental data with established rate and equilibrium models. The model was used to predict NO decomposition during lean-burn, stoichiometric burn, and slightly rich-burn cases with added EGR. NOx decomposition rates were estimated from the model to be from 35 to 42% for the lean-burn cases and from 50 to 70% for the rich-burn cases. The modeling results provided an insight as to how to maximize NOx decomposition rates for the experimental engine. Results from this experiment along with chemical kinetic modeling solutions prompted the investigation of rich-burn operating conditions

  5. Nonlinear dynamics of cycle-to-cycle combustion variations in a lean-burn natural gas engine

    International Nuclear Information System (INIS)

    Li Guoxiu; Yao Baofeng

    2008-01-01

    Temporal dynamics of the combustion process in a lean-burn natural gas engine was studied by the analysis of time series of consecutive experimental in-cylinder pressure data in this work. Methods borrowed to the nonlinear dynamical system theory were applied to analyze the in-cylinder pressure time series under operating conditions with different equivalence ratio. Phase spaces were reconstructed from the in-cylinder pressure time series and Poincare section calculated from each phase space. Poincare sections show that the in-cylinder combustion process involves chaotic behavior. Furthermore, return maps plotted from time series of indicated mean effective pressure show that both nonlinear deterministic components and stochastic components are involved in the dynamics of cycle-to-cycle combustion variations in the lean burn natural gas engine. There is a transition from stochastic behavior to noisy nonlinear determinism as equivalence ratio decreases from near stoichiometric to very lean conditions

  6. Nonlinear dynamics of cycle-to-cycle combustion variations in a lean-burn natural gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Li Guoxiu [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China)], E-mail: gxli@bjtu.edu.cn; Yao Baofeng [School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044 (China)

    2008-04-15

    Temporal dynamics of the combustion process in a lean-burn natural gas engine was studied by the analysis of time series of consecutive experimental in-cylinder pressure data in this work. Methods borrowed to the nonlinear dynamical system theory were applied to analyze the in-cylinder pressure time series under operating conditions with different equivalence ratio. Phase spaces were reconstructed from the in-cylinder pressure time series and Poincare section calculated from each phase space. Poincare sections show that the in-cylinder combustion process involves chaotic behavior. Furthermore, return maps plotted from time series of indicated mean effective pressure show that both nonlinear deterministic components and stochastic components are involved in the dynamics of cycle-to-cycle combustion variations in the lean burn natural gas engine. There is a transition from stochastic behavior to noisy nonlinear determinism as equivalence ratio decreases from near stoichiometric to very lean conditions.

  7. Investigation of combustion and thermodynamic performance of a lean burn catalytic combustion gas turbine system

    International Nuclear Information System (INIS)

    Yin Juan; Weng Yiwu

    2011-01-01

    The goals of this research were to investigate the combustion and thermodynamic performance of a lean burn catalytic combustion gas turbine. The characteristics of lean burn catalytic combustion were investigated by utilising 1D heterogeneous plug flow model which was validated by experiments. The effects of operating parameters on catalytic combustion were numerically analysed. The system models were built in ASPEN Plus and three independent design variables, i.e. compressor pressure ratio (PR), regenerator effectiveness (RE) and turbine inlet temperature (TIT) were selected to analyse the thermodynamic performance of the thermal cycle. The main results show that: simulations from 1D heterogeneous plug flow model can capture the trend of catalytic combustion and describe the behavior of the catalytic monolith in detail. Inlet temperature is the most significant parameter that impacts operation of the catalytic combustor. When TIT and RE are constant, the increase of PR results in lowering the inlet temperature of the catalytic combustor, which results in decreasing methane conversion. The peak thermal efficiency and the optimal PR at a constant TIT increase with the increase of TIT; and at the constant PR, the thermal efficiency increases with the increase of TIT. However, with lower TIT conditions, the optimal PR and the peak efficiency at a constant TIT of the LBCCGT cycle are relative low to that of the conventional cycle. When TIT and PR are constant, the decrease of RE may result in lower methane conversion. The influences of RE on the methane conversion and the thermal efficiency are more significant at higher PRs. The higher thermal efficiency for the lower RE is achieved at lower PR.

  8. Influence of cooled exhaust gas recirculation on performance, emissions and combustion characteristics of LPG fuelled lean burn SI engine

    Science.gov (United States)

    Ravi, K.; Pradeep Bhasker, J.; Alexander, Jim; Porpatham, E.

    2017-11-01

    On fuel perspective, Liquefied Petroleum Gas (LPG) provides cleaner emissions and also facilitates lean burn signifying less fuel consumption and emissions. Lean burn technology can attain better efficiencies and lesser combustion temperatures but this temperature is quite sufficient to facilitate formation of nitrogen oxide (NOx). Exhaust Gas Recirculation (EGR) for NOx reduction has been considered allover but extremely little literatures exist on the consequence of EGR on lean burn LPG fuelled spark ignition (SI) engine. The following research is carried out to find the optimal rate of EGR addition to reduce NOx emissions without settling on performance and combustion characteristics. A single cylinder diesel engine is altered to operate as LPG fuelled SI engine at a compression ratio of 10.5:1 and arrangements to provide different ratios of cooled EGR in the intake manifold. Investigations are done to arrive at optimum ratio of the EGR to reduce emissions without compromising on performance. Significant reductions in NOx emissions alongside HC and CO emissions were seen. Higher percentages of EGR further diluted the charge and lead to improper combustion and thus increased hydrocarbon emissions. Cooled EGR reduced the peak in-cylinder temperature which reduced NOx emissions but lead to misfire at lower lean limits.

  9. The Effect of Humidity on the Knock Behavior in a Medium BMEP Lean-Burn High-Speed Gas Engine

    NARCIS (Netherlands)

    van Essen, Vincent Martijn; Gersen, Sander; van Dijk, Gerco; Mundt, Torsten; Levinsky, Howard

    2016-01-01

    The effects of air humidity on the knock characteristics of fuels are investigated in a lean-burn, high-speed medium BMEP engine fueled with a CH4 + 4.7 mole% C3H8 gas mixture. Experiments are carried out with humidity ratios ranging from 4.3 to 11 g H2O/kg dry air. The measured pressure profiles at

  10. Catalytic reduction of methane/unburned hydrocarbons in smoke from lean-burn gas engines

    International Nuclear Information System (INIS)

    Wit, Jan de.

    1999-01-01

    The aim of this project has been: To describe the flue gas conditions of typical stationary gas engines for cogeneration; To evaluate the predominant causes of deactivation of oxidation catalysts under realistic operation conditions; To develop improved long-term stable oxidation catalysts; To evaluate alternative catalyst-based methane reduction technologies. Most gas engines for stationary purposes are efficient lean-burn gas engines. Both the high efficiency and the very lean operation lead to low exhaust temperatures. However, there is now a tendency to design engines with un-cooled exhaust manifolds. This leads to higher shaft efficiency and increases the exhaust temperature. Exhaust gas composition and temperatures during continuous operation and start/stops are given in this report. Analyses have been made of catalyst samples to find predominant causes for oxidation catalyst deactivation. The analyses have shown that the presence of sulphur dioxide in the flue gas causes sulphur poisoning on the active catalyst surface. This effect is dependent on both the catalyst formulation and the catalyst support material composition. Neither sintering, nor other poisoning components than sulphur have been on the examined catalyst samples. The sulphur dioxide in the exhaust is a result of the sulphur in the odorisation additive used in the natural gas (approx. 10 mg/n 3 m THT) and of the sulphur present in combusted lubrication oil. These sources leads to a level of approx. 0.3 - 0.6 ppm (vol) SO 2 in the exhaust gas. Based on a large number of laboratory tests, a new oxidation catalyst formulation has been developed and successfully tested over 5000 hours of operation at a commercial cogeneration plant. This long-term testing has been additionally supplemented by short-term testings at test sites to see performance under other operation conditions. It has been shown that a rise in flue gas temperature (from e.g. 450 deg. C) will significantly reduce the necessary

  11. Selective NOx Recirculation for Stationary Lean-Burn Natural Gas Engines

    Energy Technology Data Exchange (ETDEWEB)

    Nigel Clark; Gregory Thompson; Richard Atkinson; Richard Turton; Chamila Tissera; Emre Tatli; Andy Zimmerman

    2005-12-28

    Selective NOx Recirculation (SNR) involves cooling the engine exhaust gas and then adsorbing the oxides of nitrogen (NOx) from the exhaust stream, followed by the periodic desorption of NOx. By returning the desorbed, concentrated NOx into the engine intake and through the combustion chamber, a percentage of the NOx is decomposed during the combustion process. An initial study of NOx decomposition during lean-burn combustion was concluded in 2004 using a 1993 Cummins L10G 240hp natural gas engine. It was observed that the air/fuel ratio, injected NO (nitric oxide) quantity and engine operating points affected NOx decomposition rates of the engine. Chemical kinetic modeling results were also used to determine optimum NOx decomposition operating points and were published in the 2004 annual report. A NOx decomposition rate of 27% was measured from this engine under lean-burn conditions while the software model predicted between 35-42% NOx decomposition for similar conditions. A later technology 1998 Cummins L10G 280hp natural gas engine was procured with the assistance of Cummins Inc. to replace the previous engine used for 2005 experimental research. The new engine was equipped with an electronic fuel management system with closed-loop control that provided a more stable air/fuel ratio control and improved the repeatability of the tests. The engine was instrumented with an in-cylinder pressure measurement system and electronic controls, and was adapted to operate over a range of air/fuel ratios. The engine was connected to a newly commissioned 300hp alternating current (AC) motoring dynamometer. The second experimental campaign was performed to acquire both stoichiometric and slightly rich (0.97 lambda ratio) burn NOx decomposition rates. Effects of engine load and speed on decomposition were quantified, but Exhaust Gas Recirculation (EGR) was not varied independently. Decomposition rates of up to 92% were demonstrated. Following recommendations at the 2004 ARES peer

  12. A Laser Spark Plug Ignition System for a Stationary Lean-Burn Natural Gas Reciprocating Engine

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, D. L. [West Virginia Univ., Morgantown, WV (United States)

    2007-05-01

    To meet the ignition system needs of large bore, high pressure, lean burn, natural gas engines a side pumped, passively Q-switched, Nd:YAG laser was developed and tested. The laser was designed to produce the optical intensities needed to initiate ignition in a lean burn, high compression engine. The laser and associated optics were designed with a passive Q-switch to eliminate the need for high voltage signaling and associated equipment. The laser was diode pumped to eliminate the need for high voltage flash lamps which have poor pumping efficiency. The independent and dependent parameters of the laser were identified and explored in specific combinations that produced consistent robust sparks in laboratory air. Prior research has shown that increasing gas pressure lowers the breakdown threshold for laser initiated ignition. The laser has an overall geometry of 57x57x152 mm with an output beam diameter of approximately 3 mm. The experimentation used a wide range of optical and electrical input parameters that when combined produced ignition in laboratory air. The results show a strong dependence of the output parameters on the output coupler reflectivity, Q-switch initial transmission, and gain media dopant concentration. As these three parameters were lowered the output performance of the laser increased leading to larger more brilliant sparks. The results show peak power levels of up to 3MW and peak focal intensities of up to 560 GW/cm2. Engine testing was performed on a Ricardo Proteus single cylinder research engine. The goal of the engine testing was to show that the test laser performs identically to the commercially available flashlamp pumped actively Q-switched laser used in previous laser ignition testing. The engine testing consisted of a comparison of the in-cylinder, and emissions behavior of the engine using each of the lasers as an ignition system. All engine parameters were kept as constant as possilbe while the equivalence ratio (fueling

  13. Emission reductions through precombustion chamber design in a natural gas, lean burn engine

    International Nuclear Information System (INIS)

    Crane, M.E.; King, S.R.

    1992-01-01

    A study was conducted to evaluate the effects of various precombustion chamber design, operating and control parameters on the exhaust emissions of a natural gas engine. Analysis of the results showed that engine-out total hydrocarbons and oxides of nitrogen (NO x ) can be reduced, relative to conventional methods, through prechamber design. More specifically, a novel staged prechamber yielded significant reductions in NO x and total hydrocarbon emissions by promoting stable prechamber and main chamber ignition under fuel-lean conditions. Precise fuel control was also critical when balancing low emissions and engine efficiency (i.e., fuel economy). The purpose of this paper is to identify and explain positive and deleterious effects of natural gas prechamber design on exhaust emissions

  14. A comparison between EGR and lean-burn strategies employed in a natural gas SI engine using a two-zone combustion model

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Amr; Bari, Saiful [Sustainable Energy Centre, School of Advanced Manufacturing and Mechanical Engineering, Univ. of South Australia, Mawson Lakes SA 5095 (Australia)

    2009-12-15

    Exhaust gas recirculation (EGR) strategy has been recently employed in natural gas SI engines as an alternative to lean burn technique in order to satisfy the increasingly stringent emission standards. However, the effect of EGR on some of engine performance parameters compared to lean burn is not yet quite certain. In the current study, the effect of both EGR and lean burn on natural gas SI engine performance was compared at similar operating conditions. This was achieved numerically by developing a computer simulation of the four-stroke spark-ignition natural gas engine. A two-zone combustion model was developed to simulate the in-cylinder conditions during combustion. A kinetic model based on the extended Zeldovich mechanism was also developed in order to predict NO emission. The combustion model was validated using experimental data and a good agreement between the results was found. It was demonstrated that adding EGR to the stoichiometric inlet charge at constant inlet pressure of 130 kPa decreased power more rapidly than excess air; however, the power loss was recovered by increasing the inlet pressure from 130 kPa at zero dilution to 150 kPa at 20% EGR dilution. The engine fuel consumption increased by 10% when 20% EGR dilution was added at inlet pressure of 150 kPa compared to using 20% air dilution at 130 kPa. However, it was found that EGR dilution strategy is capable of producing extremely lower NO emission than lean burn technique. NO emission was reduced by about 70% when the inlet charge was diluted at a rate of 20% using EGR instead of excess air. (author)

  15. A comparison between EGR and lean-burn strategies employed in a natural gas SI engine using a two-zone combustion model

    International Nuclear Information System (INIS)

    Ibrahim, Amr; Bari, Saiful

    2009-01-01

    Exhaust gas recirculation (EGR) strategy has been recently employed in natural gas SI engines as an alternative to lean burn technique in order to satisfy the increasingly stringent emission standards. However, the effect of EGR on some of engine performance parameters compared to lean burn is not yet quite certain. In the current study, the effect of both EGR and lean burn on natural gas SI engine performance was compared at similar operating conditions. This was achieved numerically by developing a computer simulation of the four-stroke spark-ignition natural gas engine. A two-zone combustion model was developed to simulate the in-cylinder conditions during combustion. A kinetic model based on the extended Zeldovich mechanism was also developed in order to predict NO emission. The combustion model was validated using experimental data and a good agreement between the results was found. It was demonstrated that adding EGR to the stoichiometric inlet charge at constant inlet pressure of 130 kPa decreased power more rapidly than excess air; however, the power loss was recovered by increasing the inlet pressure from 130 kPa at zero dilution to 150 kPa at 20% EGR dilution. The engine fuel consumption increased by 10% when 20% EGR dilution was added at inlet pressure of 150 kPa compared to using 20% air dilution at 130 kPa. However, it was found that EGR dilution strategy is capable of producing extremely lower NO emission than lean burn technique. NO emission was reduced by about 70% when the inlet charge was diluted at a rate of 20% using EGR instead of excess air.

  16. Urban air quality improvement by using a CNG lean burn engine for city buses

    NARCIS (Netherlands)

    Merétei, T.; Ling, J.A.N. van; Havenith, C.

    1998-01-01

    The use of compressed natural gas (CNG)-fuelled lean-burn city bus engines has a significant potential for air quality improvement in urban areas. Particularly important is the reduction of NO, as well as particulate and non regulated HC-emissions. For this reason, a CNG-fuelled, lean-burn,

  17. Lean-burn engines UHC emission reduction

    Energy Technology Data Exchange (ETDEWEB)

    Karll, B.; Kristensen, P.G.; Nielsen, M.; Iskov, H. [Danish Gas Technology Centre a/s (Denmark); Broe Bendtsen, A.; Glarborg, P.; Dam-Johansen, K. [Technical University of Denmark. CHEC, Department of Chemical Engineering (Denmark)

    1999-04-01

    at increased NO{sub x} levels and the results show that increased NO{sub x} levels improve the UHC conversion in the exhaust reactor. The process is found to be very dependent on actual NO{sub x} levels and the exhaust reactor temperature. The exhaust temperature from lean burn engines is in the range from 450 to 550 deg. C depending on the engine settings and type. The conclusion from the tests shows that only if the temperature in the exhaust system is raised, it will be possible to use the NO{sub x} enhanced UHC oxidation process for post oxidation. Injection of hydrogen peroxide caused a significant reduction in the stack emission of UHC by conversion of UHC at conditions where the exhaust reactor otherwise was unable to oxidise UHC. The stack emission of UHC was reduced by 40-60% during test engine conditions. (EHS) EFP-96; 14 refs.

  18. Lean-burn engines UHC emission reduction

    International Nuclear Information System (INIS)

    Karll, B.; Kristensen, P.G.; Nielsen, M.; Iskov, H.; Broe Bendtsen, A.; Glarborg, P.; Dam-Johansen, K.

    1999-01-01

    the results show that increased NO x levels improve the UHC conversion in the exhaust reactor. The process is found to be very dependent on actual NO x levels and the exhaust reactor temperature. The exhaust temperature from lean burn engines is in the range from 450 to 550 deg. C depending on the engine settings and type. The conclusion from the tests shows that only if the temperature in the exhaust system is raised, it will be possible to use the NO x enhanced UHC oxidation process for post oxidation. Injection of hydrogen peroxide caused a significant reduction in the stack emission of UHC by conversion of UHC at conditions where the exhaust reactor otherwise was unable to oxidise UHC. The stack emission of UHC was reduced by 40-60% during test engine conditions. (EHS) EFP-96; 14 refs

  19. The relative effects of fuel concentration, residual-gas fraction, gas motion, spark energy and heat losses to the electrodes on flame-kernel development in a lean-burn spark ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Aleiferis, P.G.; Taylor, A.M.K.P. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Dept. of Mechanical Engineering; Ishii, K. [Honda International Technical School, Saitama (Japan); Urata, Y. [Honda R and D Co., Ltd., Tochigi (Japan). Tochigi R and D Centre

    2004-04-01

    The potential of lean combustion for the reduction in exhaust emissions and fuel consumption in spark ignition engines has long been established. However, the operating range of lean-burn spark ignition engines is limited by the level of cyclic variability in the early-flame development stage that typically corresponds to the 0-5 per cent mass fraction burned duration. In the current study, the cyclic variations in early flame development were investigated in an optical stratified-charge spark ignition engine at conditions close to stoichiometry [air-to-fuel ratio (A/F) = 15] and to the lean limit of stable operation (A/F = 22). Flame images were acquired through either a pentroof window ('tumble plane' of view) or the piston crown ('swirl plane' of view) and these were processed to calculate the intra-cycle flame-kernel radius evolution. In order to quantify the relative effects of local fuel concentration, gas motion, spark-energy release and heat losses to the electrodes on the flame-kernel growth rate, a zero-dimensional flame-kernel growth model, in conjunction with a one-dimensional spark ignition model, was employed. Comparison of the calculated flame-radius evolutions with the experimental data suggested that a variation in A/F around the spark plug of {delta}(A/F) {approx} 4 or, in terms of equivalence ratio {phi}, a variation in {delta}{phi} {approx} 0.15 at most was large enough to account for 100 per cent of the observed cyclic variability in flame-kernel radius. A variation in the residual-gas fraction of about 20 per cent around the mean was found to account for up to 30 per cent of the variability in flame-kernel radius at the timing of 5 per cent mass fraction burned. The individual effect of 20 per cent variations in the 'mean' in-cylinder velocity at the spark plug at ignition timing was found to account for no more than 20 per cent of the measured cyclic variability in flame kernel radius. An individual effect of

  20. Vortex combustor for low NOX emissions when burning lean premixed high hydrogen content fuel

    Science.gov (United States)

    Steele, Robert C; Edmonds, Ryan G; Williams, Joseph T; Baldwin, Stephen P

    2012-11-20

    A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

  1. NOx storage and reduction over a lean-burn automotive catalyst

    NARCIS (Netherlands)

    Scholz, C.M.L.

    2007-01-01

    Nowadays, there is an increased interest in lean-burn technologies, i.e. diesel and lean-burn gasoline engines, mainly due to their higher fuel efficiency compared to conventional gasoline engines. Lean-burn engines work under excess oxygen and consequently produce oxygen-rich exhaust. This

  2. Development of lean burn gas engines using pilot fuel for ignition source; Developpement d'un moteur a gaz avec pre-injection de carburant pour la source d'allumage

    Energy Technology Data Exchange (ETDEWEB)

    Sakonji, T.; Saito, H.; Sakurai, T. [Tokyo Gas Co., Ltd. (Japan); Hirashima, T.; Kanno, K. [Nissan Diesel Motor Co., Ltd. (Japan)

    2000-07-01

    A development was conducted to investigate the performance of an open chamber gas engine with pilot fuel for ignition source. Experiments were conducted by using a gas engine equipped with a common-rail injection system. Main gas fuel is supplied to the engine cylinder, and then a small quantity of diesel fuel (approximately 1 % of total fuel energy input) was injected into the main chamber for ignition. The single cylinder prototype gas engine has demonstrated superior performance, such as, a shaft-end thermal efficiency of 36.7% with NO{sub x} level of 0.4 g/kW-h, which equals those of conventional spark ignited pre-chamber lean burn gas engines. For the next step, the multi-cylinder gas engine has been developed. That has 138 mm bore, 142 mm stroke, V8 configuration and 229 kW engine output 1500 rpm. This engine can also run with only diesel fuel for Standby-Power-Concurrent Co-generation. (authors)

  3. Catalytic removal of methane and NO{sub x} in lean-burn natural-gas engine exhaust; Elimination par catalyse du methane et des NO{sub x} dans les echappements de moteur au gaz naturel a basse combustion

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, H.; Satokawa, S.; Yahagi, M.; Yamaseki, K.; Hoshi, F.; Uchida, H.; Yokota, H. [Tokyo Gas Co., Ltd. (Japan)

    2000-07-01

    We have developed a new catalytic system to reduce the emissions of hydrocarbons, carbon monoxide (CO), and nitrogen oxides (NO{sub x}) contained in the exhaust gases from a lean-burn natural-gas engine. Catalytic oxidation of unburned hydrocarbons and CO in the exhaust has been studied for noble metals supported on alumina. (1) A low-loading catalyst comprising platinum supported on alumina (Pt/alumina) was efficient for the oxidation of CO and hydrocarbons without methane. The CO conversions were maintained at more than 98 % for 20,000 hours over the Pt/alumina. (2) A catalyst comprising platinum and palladium supported on alumina (Pt-Pd/alumina) exhibited higher levels of oxidation of hydrocarbons (including methane) than a catalyst comprising only palladium supported on alumina (Pd/alumina). Its oxidation also lasted longer. The combined effects of the platinum and palladium metals achieved high sulfur dioxide resistance. Increasing the palladium content in the Pt-Pd/alumina catalyst increased the level of oxidation and extended the lifetime of the catalyst. (3) A catalyst comprising silver supported on alumina (Ag/alumina) was effective at reducing the amount of NO{sub X} by using the unburned hydrocarbons in the exhaust gas. The NO{sub x} conversions over Ag/alumina were maintained at more than 30 % for 3,500 hours. We describe a total clean-up system consisting of a Ag/alumina catalyst and a Pt-Pd/alumina catalyst in series on the exhaust gas stream. (authors)

  4. Energy efficiency analyses of active flow aftertreatment systems for lean burn internal combustion engines

    International Nuclear Information System (INIS)

    Zheng Ming; Reader, Graham T.

    2004-01-01

    The use of three way catalytic converters in stoichiometric burn reciprocating internal combustion engine systems has proved to be an effective and efficient method for reducing the level of criteria pollutants. However, such passive systems have not been as successful in emission amelioration when combined with lean burn engines. This is because of the thermochemical nature of the exhaust gases generated by such engines. The high content of exhaust oxygen largely negates the effectiveness of three way catalytic converters, and the comparatively low temperature of the combusted gases means that supplemental energy has to be added to these gases to enable the converter to function correctly. This requirement severely reduces the energy efficiency of conventional passive aftertreatment systems. However, initial empirical studies have indicated that a possible means of improving the performance of aftertreatment devices when used with lean burn engine systems is to use active flow control of the exhaust gases. These results are reported in this paper. This concept has been further investigated by developing an energy efficiency analysis that enables the effects on aftertreatment performance of different gas flow rates, flow reversal frequencies and monolith solid properties to be investigated. Simulation results indicate that through active thermal management, the supplemental energy consumption can be drastically reduced

  5. Plasma-assisted heterogeneous catalysis for NOx reduction in lean-burn engine exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Penetrante, B.M.; Hsaio, M.C.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States); Wan, C.Z.; Rice, G.W.; Voss, K.E. [Engelhard Corp., Iselin, NJ (United States)

    1997-12-31

    This paper discusses the combination of a plasma with a catalyst to improve the reduction of NO{sub x} under lean-burn conditions. The authors have been investigating the effects of a plasma on the NO{sub x} reduction activity and temperature operating window of various catalytic materials. One of the goals is to develop a fundamental understanding of the interaction between the gas-phase plasma chemistry and the heterogeneous chemistry on the catalyst surface. The authors have observed that plasma assisted heterogeneous catalysis can facilitate NO{sub x} reduction under conditions that normally make it difficult for either the plasma or the catalyst to function by itself. By systematically varying the plasma electrode and catalyst configuration, they have been able to elucidate the process by which the plasma chemistry affects the chemical reduction of NO{sub x} on the catalyst surface. They have discovered that the main effect of the plasma is to induce the gas-phase oxidation of NO to NO{sub 21}. The reduction of NO{sub x} to N{sub 2} is then accomplished by heterogeneous reaction of O with activated hydrocarbons on the catalyst surface. The use of a plasma opens the opportunity for a new class of catalysts that are potentially more durable, more active, more selective and more sulfur-tolerant compared to conventional lean-NO{sub x} catalysts.

  6. Temperature and air-fuel ratio dependent specific heat ratio functions for lean burned and unburned mixture

    International Nuclear Information System (INIS)

    Ceviz, M.A.; Kaymaz, I.

    2005-01-01

    The most important thermodynamic property used in heat release calculations for engines is the specific heat ratio. The functions proposed in the literature for the specific heat ratio are temperature dependent and apply at or near stoichiometric air-fuel ratios. However, the specific heat ratio is also influenced by the gas composition in the engine cylinder and especially becomes important for lean combustion engines. In this study, temperature and air-fuel ratio dependent specific heat ratio functions were derived to minimize the error by using an equilibrium combustion model for burned and unburned mixtures separately. After the error analysis between the equilibrium combustion model and the derived functions is presented, the results of the global specific heat ratio function, as varying with mass fraction burned, were compared with the proposed functions in the literature. The results of the study showed that the derived functions are more feasible at lean operating conditions of a spark ignition engine

  7. Rich-burn, flame-assisted fuel cell, quick-mix, lean-burn (RFQL) combustor and power generation

    Science.gov (United States)

    Milcarek, Ryan J.; Ahn, Jeongmin

    2018-03-01

    Micro-tubular flame-assisted fuel cells (mT-FFC) were recently proposed as a modified version of the direct flame fuel cell (DFFC) operating in a dual chamber configuration. In this work, a rich-burn, quick-mix, lean-burn (RQL) combustor is combined with a micro-tubular solid oxide fuel cell (mT-SOFC) stack to create a rich-burn, flame-assisted fuel cell, quick-mix, lean-burn (RFQL) combustor and power generation system. The system is tested for rapid startup and achieves peak power densities after only 35 min of testing. The mT-FFC power density and voltage are affected by changes in the fuel-lean and fuel-rich combustion equivalence ratio. Optimal mT-FFC performance favors high fuel-rich equivalence ratios and a fuel-lean combustion equivalence ratio around 0.80. The electrical efficiency increases by 150% by using an intermediate temperature cathode material and improving the insulation. The RFQL combustor and power generation system achieves rapid startup, a simplified balance of plant and may have applications for reduced NOx formation and combined heat and power.

  8. Lean-burn stratified combustion at gasoline engines; Magere Schichtverbrennung beim Ottomotor

    Energy Technology Data Exchange (ETDEWEB)

    Breitbach, Hermann [Daimler AG, Stuttgart (Germany). Entwicklung Einspritzung und Betriebsstoffe; Waltner, Anton [Daimler AG, Stuttgart (Germany). Verbrennungsentwicklung Pkw-Ottomotoren; Landenfeld, Tilo [Robert Bosch GmbH, Schwieberdingen (Germany). Hochdruckeinspritzung Piezo; Porten, Guido [Robert Bosch GmbH, Schwieberdingen (Germany). Systementwicklung Benzindirekteinspritzung

    2013-05-01

    Spray-guided lean-burn combustion is an integral part of the Mercedes-Benz technology strategy for highly efficient and clean gasoline engines. With regard to the excellent fuel efficiency combined with outstanding specific power, a good combustion system robustness and the low particulate emissions, the concept offers a very good cost/benefit ratio especially for the Euro 6 emission legislation. Thus, Mercedes-Benz believes, that the sprayguided lean-burn combustion offers the by far highest future viability of gasoline engine combustion systems.

  9. Reduce NOx Emissions by Adsorber-Reduction Catalyst on Lean Burn Gasoline Engine

    Directory of Open Access Journals (Sweden)

    Dongpeng Yue

    2013-09-01

    Full Text Available The effect of a new catalyst system composed of traditional three way catalyst converter and adsorber-reduction catalysis converter on the emission characteristics and BSFC (Breake Specific Fuel Consumption- BSFCof a lean burn gasoline engine operated were investigated in this paper under different schemes of catalyst converter arrangement and different speeds and loads. The results show that the position of Three Way Catalyst is before the NOx adsorber Catalyst was the best scheme of catalyst converter arrangement. Which has the highest converter efficiency of reduction NOx emission in lean burn gasoline engine. The effects of speed on the exhaust emission and BSFC were also related to the ratio of lean burn time to rich burn time and the absolute value of both time of the adsorber-reduction catalyst converter. The load of the engine was the main influential factor to the exhaust emission characteristics and BSFC of lean burn gasoline engine, and the more load of the engine was, the more NOx emission , the less NOx conversion rate (CNOx and the better BSFC were.

  10. Multi-Stage Selective Catalytic Reduction of NOx in Lean-Burn Engine Exhaust

    National Research Council Canada - National Science Library

    Penetrante, B

    1997-01-01

    .... A plasma can also be used to oxidize NO to NO2. This paper compares the multi-stage catalytic scheme with the plasma-assisted catalytic scheme for reduction of NOx in lean-burn engine exhausts. The advantages of plasma oxidation over catalytic oxidation are presented.

  11. Gas fireplace contact burns in young children.

    Science.gov (United States)

    Zettel, Julie C; Khambalia, Amina; Barden, Wendy; Murthy, Trisha; Macarthur, Colin

    2004-01-01

    Contact burns from domestic appliances are common in young children. Recently, gas fireplaces have been recognized as a potential cause of contact burns in young children. We sought to quantify the frequency of gas fireplace contact burns in young children, to identify the etiology of contact, to describe the clinical presentation, and to describe clinical outcomes. Children with gas fireplace contact burn injuries presenting to The Hospital for Sick Children in Toronto (1999-2002) were identified using three data sources: the Canadian Hospitals Injury Reporting and Prevention Program Database, the Burn Unit Registry, and the Rehabilitation Services Database. Demographic, clinical, and outcomes data were collected on all children. During the 4-year study period, 27 children presented to the hospital because of a gas fireplace contact burn (approximately 9% of all contact burns). The median age of the children was 14 months (range, 8-36 months), with 16 boys (59%). Most children were burned in their own home. With regard to etiology, 10 children (37%) lost their balance near the fireplace, 2 (7%) walked too close to the glass front, and 8 (30%) touched the glass front out of curiosity. Almost half (44%) of the children burned the palms and digits of both hands. The median total burn surface area was 1% (range, 0.2-2.5%). In total, 30% of children were admitted to hospital, and 11% required skin grafts. All children had full wound closure after 4 to 43 days. Given the etiology of these burns (loss of balance or curiosity), passive prevention, such as barriers or changes in the composition of glass panels, may be the most effective approach to combat them.

  12. An experimental investigation of a lean-burn natural-gas pre-chamber spark ignition engine for cogeneration; Swiss Motor. Modification d'un moteur diesel pour le fonctionnement au gaz naturel en cogeneration. Fonctionnement avec prechambre de combustion

    Energy Technology Data Exchange (ETDEWEB)

    Roethlisberger, R.; Favrat, D.

    2001-07-01

    This thesis presented at the Department of Mechanical Engineering of the Swiss Federal Institute of Technology in Lausanne describes the conversion and testing of a commercial diesel engine for use as a lean-burn, natural gas, pre-chamber, spark ignition engine with a rated power of 150 kW, in combined heat and power (CHP) plants. The objective of the investigations - to evaluate the potential of reducing exhaust gas emissions - is discussed in detail with respect to NO{sub x} and CO emissions. The approach adopted includes both experimental work and numerical simulation. The report describes the testing facilities used. The results obtained with experimental spark-plug configurations based on simulation results are presented and the influence of various pre-chamber configuration variants are discussed. The results of the tests are presented and the significant reduction of NO{sub x}, CO and unburned-hydrocarbon (THC) emissions are discussed. The authors state that the engine, which achieves a fuel efficiency of more than 36.5%, fulfils the Swiss requirements on exhaust gas emissions. Also, ways of compensating for the slight loss in fuel-conversion efficiency in the pre-chamber configuration are discussed.

  13. Burning low volatile fuel in tangentially fired furnaces with fuel rich/lean burners

    International Nuclear Information System (INIS)

    Wei Xiaolin; Xu Tongmo; Hui Shien

    2004-01-01

    Pulverized coal combustion in tangentially fired furnaces with fuel rich/lean burners was investigated for three low volatile coals. The burners were operated under the conditions with varied value N d , which means the ratio of coal concentration of the fuel rich stream to that of the fuel lean stream. The wall temperature distributions in various positions were measured and analyzed. The carbon content in the char and NO x emission were detected under various conditions. The new burners with fuel rich/lean streams were utilized in a thermal power station to burn low volatile coal. The results show that the N d value has significant influences on the distributions of temperature and char burnout. There exists an optimal N d value under which the carbon content in the char and the NO x emission is relatively low. The coal ignition and NO x emission in the utilized power station are improved after retrofitting the burners

  14. IGNITION IMPROVEMENT OF LEAN NATURAL GAS MIXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Jason M. Keith

    2005-02-01

    This report describes work performed during a thirty month project which involves the production of dimethyl ether (DME) on-site for use as an ignition-improving additive in a compression-ignition natural gas engine. A single cylinder spark ignition engine was converted to compression ignition operation. The engine was then fully instrumented with a cylinder pressure transducer, crank shaft position sensor, airflow meter, natural gas mass flow sensor, and an exhaust temperature sensor. Finally, the engine was interfaced with a control system for pilot injection of DME. The engine testing is currently in progress. In addition, a one-pass process to form DME from natural gas was simulated with chemical processing software. Natural gas is reformed to synthesis gas (a mixture of hydrogen and carbon monoxide), converted into methanol, and finally to DME in three steps. Of additional benefit to the internal combustion engine, the offgas from the pilot process can be mixed with the main natural gas charge and is expected to improve engine performance. Furthermore, a one-pass pilot facility was constructed to produce 3.7 liters/hour (0.98 gallons/hour) DME from methanol in order to characterize the effluent DME solution and determine suitability for engine use. Successful production of DME led to an economic estimate of completing a full natural gas-to-DME pilot process. Additional experimental work in constructing a synthesis gas to methanol reactor is in progress. The overall recommendation from this work is that natural gas to DME is not a suitable pathway to improved natural gas engine performance. The major reasons are difficulties in handling DME for pilot injection and the large capital costs associated with DME production from natural gas.

  15. NO adsorption behaviors of the MnO{sub x} catalysts in lean-burn atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Li [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Tianjin Key Laboratory of Applied Catalysis Science and Technology, Tianjin 300072 (China); The Co-innovation Center of Chemistry and Chemical Engineering of Tianjin, Tianjin 300072 (China); Xian, Hui [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Pei-Yang Distillation Engineering Limited Company, Tianjin 300072 (China); Li, Qi-Feng; Chen, Da [Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, School of Precision Instruments and Opto-electronics Engineering, Tianjin University, Tianjin 300072 (China); Tan, Yi-Sheng [State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Science, Taiyuan 030001 (China); Zhang, Jing; Zheng, Li-Rong [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Li, Xin-Gang, E-mail: xingang_li@tju.edu.cn [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Tianjin Key Laboratory of Applied Catalysis Science and Technology, Tianjin 300072 (China); The Co-innovation Center of Chemistry and Chemical Engineering of Tianjin, Tianjin 300072 (China)

    2013-09-15

    Highlights: • α-Mn{sub 2}O{sub 3} is a promising NO{sub x} adsorber for lean-burn exhausts even at low temperatures. • NO{sub x} was weakly bonded on α-Mn{sub 2}O{sub 3}, but strongly bonded on β-MnO{sub 2}. • NO could efficiently adsorb/desorb within the lean/rich cyclings over α-Mn{sub 2}O{sub 3}. • The superficial oxygen species plays a key role for the NO oxidation over α-Mn{sub 2}O{sub 3}. • The NO adsorption and oxidation follow the L–H and/or E–R mechanism over α-Mn{sub 2}O{sub 3}. -- Abstract: NO{sub x} emission control of lean-burn engines is one of the great challenges in the world. Herein, the MnO{sub x} model catalysts with the different calcination temperatures were synthesized to investigate their NO adsorbability for lean-burn exhausts. The transformation from (β-)MnO{sub 2} to (α-)Mn{sub 2}O{sub 3} following the increased calcination temperatures was evidenced from the viewpoint of the local atomic level. Among these samples, the one calcined at 550 °C containing the single α-Mn{sub 2}O{sub 3} phase displayed the best NO adsorbability: NO was mainly adsorbed in the forms of NO/nitrites and NO{sub 2}/nitrates at the low and high temperatures, respectively; the NO oxidation ability displayed the volcano-shape following the increased operating temperatures, and reached the maximum, i.e. 92.4% of the NO-to-NO{sub 2} conversion, at 250 °C. Moreover, this sample presented the efficiently reversible NO adsorption/desorption performance in alternative lean-burn/fuel-rich atmospheres, due to the weakly bonded NO{sub x} on it. The superficial oxygen species plays a critical role for the NO oxidation over α-Mn{sub 2}O{sub 3}. The consumed superficial oxygen could be further compensated by the gaseous and lattice oxygen therein. Our findings show that the α-Mn{sub 2}O{sub 3} material is a promising NO{sub x} adsorber for lean-burn exhausts even at low operating temperatures.

  16. NO adsorption behaviors of the MnOx catalysts in lean-burn atmospheres

    International Nuclear Information System (INIS)

    Guo, Li; Xian, Hui; Li, Qi-Feng; Chen, Da; Tan, Yi-Sheng; Zhang, Jing; Zheng, Li-Rong; Li, Xin-Gang

    2013-01-01

    Highlights: • α-Mn 2 O 3 is a promising NO x adsorber for lean-burn exhausts even at low temperatures. • NO x was weakly bonded on α-Mn 2 O 3 , but strongly bonded on β-MnO 2 . • NO could efficiently adsorb/desorb within the lean/rich cyclings over α-Mn 2 O 3 . • The superficial oxygen species plays a key role for the NO oxidation over α-Mn 2 O 3 . • The NO adsorption and oxidation follow the L–H and/or E–R mechanism over α-Mn 2 O 3 . -- Abstract: NO x emission control of lean-burn engines is one of the great challenges in the world. Herein, the MnO x model catalysts with the different calcination temperatures were synthesized to investigate their NO adsorbability for lean-burn exhausts. The transformation from (β-)MnO 2 to (α-)Mn 2 O 3 following the increased calcination temperatures was evidenced from the viewpoint of the local atomic level. Among these samples, the one calcined at 550 °C containing the single α-Mn 2 O 3 phase displayed the best NO adsorbability: NO was mainly adsorbed in the forms of NO/nitrites and NO 2 /nitrates at the low and high temperatures, respectively; the NO oxidation ability displayed the volcano-shape following the increased operating temperatures, and reached the maximum, i.e. 92.4% of the NO-to-NO 2 conversion, at 250 °C. Moreover, this sample presented the efficiently reversible NO adsorption/desorption performance in alternative lean-burn/fuel-rich atmospheres, due to the weakly bonded NO x on it. The superficial oxygen species plays a critical role for the NO oxidation over α-Mn 2 O 3 . The consumed superficial oxygen could be further compensated by the gaseous and lattice oxygen therein. Our findings show that the α-Mn 2 O 3 material is a promising NO x adsorber for lean-burn exhausts even at low operating temperatures

  17. Model predictive control of a lean-burn gasoline engine coupled with a passive selective catalytic reduction system

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Pingen [Tennessee Technological University (TTU); Lin, Qinghua [Tennessee Technological University (TTU); Prikhodko, Vitaly Y. [ORNL

    2017-10-01

    Lean-burn gasoline engines have demonstrated 10–20% engine efficiency gain over stoichiometric engines and are widely considered as a promising technology for meeting the 54.5 miles-per-gallon (mpg) Corporate Average Fuel Economy standard by 2025. Nevertheless, NOx emissions control for lean-burn gasoline for meeting the stringent EPA Tier 3 emission standards has been one of the main challenges towards the commercialization of highly-efficient lean-burn gasoline engines in the United States. Passive selective catalytic reduction (SCR) systems, which consist of a three-way catalyst and SCR, have demonstrated great potentials of effectively reducing NOx emissions for lean gasoline engines but may cause significant fuel penalty due to ammonia generation via rich engine combustion. The purpose of this study is to develop a model-predictive control (MPC) scheme for a lean-burn gasoline engine coupled with a passive SCR system to minimize the fuel penalty associated with passive SCR operation while satisfying stringent NOx and NH3 emissions requirements. Simulation results demonstrate that the MPC-based control can reduce the fuel penalty by 47.7% in a simulated US06 cycle and 32.0% in a simulated UDDS cycle, compared to the baseline control, while achieving over 96% deNOx efficiency and less than 15 ppm tailpipe ammonia slip. The proposed MPC control can potentially enable high engine efficiency gain for highly-efficient lean-burn gasoline engine while meeting the stringent EPA Tier 3 emission standards.

  18. Detailed characterization of particulate matter emitted by lean-burn gasoline direct injection engine

    Energy Technology Data Exchange (ETDEWEB)

    Zelenyuk, Alla [Pacific Northwest National Laboratory, Richland, WA, USA; Wilson, Jacqueline [Pacific Northwest National Laboratory, Richland, WA, USA; Imre, Dan [Imre Consulting, Richland, WA, USA; Stewart, Mark [Pacific Northwest National Laboratory, Richland, WA, USA; Muntean, George [Pacific Northwest National Laboratory, Richland, WA, USA; Storey, John [Oak Ridge National Laboratory, Knoxville, TN, USA; Prikhodko, Vitaly [Oak Ridge National Laboratory, Knoxville, TN, USA; Lewis, Samuel [Oak Ridge National Laboratory, Knoxville, TN, USA; Eibl, Mary [Oak Ridge National Laboratory, Knoxville, TN, USA; Parks, Jim [Oak Ridge National Laboratory, Knoxville, TN, USA

    2016-11-10

    This study presents detailed characterization of the chemical and physical properties of PM emitted by a 2.0L BMW lean-burn turbocharged GDI engine operated under a number of combustion strategies that include lean homogeneous, lean stratified, stoichiometric, and fuel rich conditions. We characterized PM number concentrations, size distributions, and the size, mass, compositions, and effective density of fractal and compact individual exhaust particles. For the fractal particles, these measurements yielded fractal dimension, average diameter of primary spherules, and number of spherules, void fraction, and dynamic shape factors as function of particle size. Overall, the PM properties were shown to vary significantly with engine operation condition. Lean stratified operation yielded the most diesel-like size distribution and the largest PM number and mass concentrations, with nearly all particles being fractal agglomerates composed of elemental carbon with small amounts of ash and organics. In contrast, stoichiometric operation yielded a larger fraction of ash particles, especially at low speed and low load. Three distinct forms of ash particles were observed, with their fractions strongly dependent on engine operating conditions: sub-50 nm ash particles, abundant at low speed and low load, ash-containing fractal particles, and large compact ash particles that significantly contribute to PM mass loadings

  19. Flashback mechanisms in lean premixed gas turbine combustion

    CERN Document Server

    Benim, Ali Cemal

    2014-01-01

    Blending fuels with hydrogen offers the potential to reduce NOx and CO2 emissions in gas turbines, but doing so introduces potential new problems such as flashback.  Flashback can lead to thermal overload and destruction of hardware in the turbine engine, with potentially expensive consequences. The little research on flashback that is available is fragmented. Flashback Mechanisms in Lean Premixed Gas Turbine Combustion by Ali Cemal Benim will address not only the overall issue of the flashback phenomenon, but also the issue of fragmented and incomplete research.Presents a coherent review of f

  20. Trace gas emissions from burning Florida wetlands

    Science.gov (United States)

    Cofer, Wesley R.; Levine, Joel S.; Winstead, Edward L.; Lebel, Peter J.; Koller, Albert M.; Hinkle, C. Ross

    1990-02-01

    Measurements of biomass burn-produced trace gases are presented that were obtained using a helicopter at low altitudes above burning Florida wetlands on November 9, 1987, and from both helicopter and light-aircraft samplings on November 7, 1988. Carbon dioxide (CO2) normalized emission ratios (ΔX/ΔCO2; V/V; where X is trace gas) for carbon monoxide (CO), hydrogen (H2), methane (CH4), total nonmethane hydrocarbons (TNMHC), and nitrous oxide (N2O) were obtained over burning graminoid wetlands consisting primarily of Spartina bakeri and Juncus roemerianus. Some interspersed scrub oak (Quercus spp) and saw palmetto (Screnoa repens) were also burned. No significant differences were observed in the emission ratios determined for these gases from samples collected over flaming, mixed, and smoldering phases of combustion during the 1987 fire. Combustion-categorized differences in emission ratios were small for the 1988 fire. Combustion efficiency was relatively good (low emission ratios for reduced gases) for both fires. We believe that the consistently low emission ratios were a unique result of graminoid wetlands fires, in which the grasses and rushes (both small-size fuels) burned rapidly down to standing water and were quickly extinguished. Consequently, the efficiency of the combustion was good and the amount and duration of smoldering combustion was greatly diminished.

  1. Gas chromatographic determination of Di-n-butyl phosphate in radioactive lean organic solvent of FBTR carbide fuel reprocessing

    International Nuclear Information System (INIS)

    Velavendan, P.; Ganesh, S.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2011-01-01

    In the present work Di-n- butyl phosphate (DBP) a degraded product of Tri-n-butyl phosphate (TBP) formed by acid hydrolysis and radiolysis in the PUREX process was analyzed. Lean organic streams of different fuel burn-up FBTR carbide fuel reprocessing solution was determined by standard Gas Chromatographic technique. The method involves the conversion of non-volatile Di-n-butyl phosphate into volatile and stable derivatives by the action of diazomethane and then determined by Gas Chromatograph (GC). A calibration graph was made for DBP concentration range of 200-2000 ppm with correlation coefficient of 0.99587 and RSD 1.2 %. (author)

  2. Attempt of lean burn of a 4 cycle gasoline engine by the aid of low pressure air assisted in-cylinder injection; Tonai kuki nenryo funsha ni yoru lean burn no kokoromi

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, S; Kondo, M; Sekiya, Y; Murayama, T [Hokkaido Automotive Engineering College, Hokkaido (Japan)

    1997-10-01

    Comparable performance and exhaust emission with conventional carburetor was obtained by a low Pressure air assisted in-cylinder injection system. And lean burn of idling and light load operation till A/F=70 was realized by installing a spark Plug and a reed type injection nozzle in a divided combustion chambaer of a 4 cycle gasoline engine. 2 refs., 10 figs.

  3. Effect of hydrogen addition on burning rate and surface density of turbulent lean premixed methane-air flames

    International Nuclear Information System (INIS)

    Guo, H.; Tayebi, B.; Galizzi, C.; Escudie, D.

    2009-01-01

    Hydrogen (H 2 ) is a clean burning component, but relatively expensive. Mixing a small amount of hydrogen with other fuels is an effective way to use H 2 . H 2 enriched combustion significantly improves fuel efficiency and reduces pollutant (nitrogen oxide and particulate matter) emissions. This presentation discussed the effect of hydrogen addition on burning rate and surface density of turbulent lean premixed methane-air flames. The presentation discussed flame configuration; the experimental methodology using laser tomography; and results for typical images, burning velocity, ratio of turbulent to laminar burning velocities, flame surface density, curvature, flame brush thickness, and integrated flame surface area. It was concluded that the increase of turbulent burning velocity was faster than that of laminar burning velocity, which contradicted traditional theory. figs.

  4. A study on the criterions of lean burn limit for an LPG EFI engine. Paper no. IGEC-1-140

    International Nuclear Information System (INIS)

    Li, L.; Wang, Z.; Xiao, Z.; Wang, H.; Deng, B.; Su, Y.

    2005-01-01

    Based on electronic low-pressure gaseous injection, the comparing analysis of several methods for the criterions of lean burn limit in an LPG engine is presented. Experiments are carried out in a single cylinder, four-stroke, water-cooled, 125cc engine with electronic LPG injection. According to the analysis of multi-parameters in and out cylinder, it shows that variation coefficient of indicated pressure which is the classical judgment of lean burn limit, the HC emission, HC emission rising gradient, the misfiring rate and the variation coefficient of the crank angle of the maximum combustion pressure can be as the criterions for lean burn limit. For the test engine, 15% as variation coefficient of indicative mean pressure, 500 x 10 -6 as HC emission, 2000 x 10 -6 as HC emission rising ratio, 1% as misfiring rate and 50% as variation coefficient of the crank angle of the maximum combustion pressure can be as the judgment criterions of LPG lean burn limits. (author)

  5. Air-fuel ratio control of a lean burn Si engine using fuzzy self tuning method

    International Nuclear Information System (INIS)

    Akhlaghi, M.; Bakhtiari Nejad, F.; Azadi, S.

    2000-01-01

    Reducing the exhaust emission of an spark ignition engine by means of engine modifications requires consideration of the effects of these modifications on the variations of crankshaft torque and the engine roughness respectively. Only if the roughness does not exceed a certain level the vehicle do not begin to surge. This paper presents a method for controlling the air-fuel ratio for a lean burn engine. Fuzzy rules and reasoning are utilized on-line to determine the control parameters. The main advantages of this method are simple structure and robust performance in a wide range of operating conditions. A non-linear model of an Si engine with the engine torque irregularity simulation is used in this study

  6. Multi-stage selective catalytic reduction of NOx in lean burn engine exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Penetrante, B.M.; Hsaio, M.C.; Merritt, B.T.; Vogtlin, G.E. [Lawrence Livermore National Lab., CA (United States)

    1997-12-31

    Many studies suggest that the conversion of NO to NO{sub 2} is an important intermediate step in the selective catalytic reduction (SCR) of NO{sub x} to N{sub 2}. Some effort has been devoted to separating the oxidative and reductive functions of the catalyst in a multi-stage system. This method works fine for systems that require hydrocarbon addition. The hydrocarbon has to be injected between the NO oxidation catalyst and the NO{sub 2} reduction catalyst; otherwise, the first-stage oxidation catalyst will also oxidize the hydrocarbon and decrease its effectiveness as a reductant. The multi-stage catalytic scheme is appropriate for diesel engine exhausts since they contain insufficient hydrocarbons for SCR, and the hydrocarbons can be added at the desired location. For lean-burn gasoline engine exhausts, the hydrocarbons already present in the exhausts will make it necessary to find an oxidation catalyst that can oxidize NO to NO{sub 2} but not oxidize the hydrocarbon. A plasma can also be used to oxidize NO to NO{sub 2}. Plasma oxidation has several advantages over catalytic oxidation. Plasma-assisted catalysis can work well for both diesel engine and lean-burn gasoline engine exhausts. This is because the plasma can oxidize NO in the presence of hydrocarbons without degrading the effectiveness of the hydrocarbon as a reductant for SCR. In the plasma, the hydrocarbon enhances the oxidation of NO, minimizes the electrical energy requirement, and prevents the oxidation of SO{sub 2}. This paper discusses the use of multi-stage systems for selective catalytic reduction of NO{sub x}. The multi-stage catalytic scheme is compared to the plasma-assisted catalytic scheme.

  7. Development II of ion current combustion control system. Application to the lean burn system of the micro vehicle engine; Ion denryu wo mochiita nensho seigyo system no kaihatsu. 2. Keijidosha engine wo mochiita lean burn eno oyo

    Energy Technology Data Exchange (ETDEWEB)

    Iida, T; Asano, M; Kajitani, M; Kuma, t; Morinaga, Y [Daihatsu Motor Co. Ltd., Osaka (Japan)

    1997-10-01

    The lean bum engine has not been introduced into the micro vehicle so far because of the low cost requirement and small displacement, in spite of it is one of the effective solutions which increase the fuel economy. By the way, we had already reported in the former paper that we developed the ion current combustion control system the architecture of which is cheaper than the other system. In this paper, we described the way how the above system is applied to the lean burn system of the micro vehicle engine and also we reported the gain of fuel economy and the exhaust emission level. 5 refs., 11 figs., 2 tabs.

  8. Study of gas (CNG) SI engine with pre-chamber. Improvement of the indicated thermal efficiency on lean mixture with EGR and supercharging; Fukushitsushiki hibana tenka asshuku tennen gas (CNG) engine ni kansuru kenkyu. Kakyu to EGR ni yoru kihakuiki no netsukoritsu kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Yonetani, H.; Fukutani, I. [Polytechnic University, Kanagawa (Japan)

    1998-10-15

    As lean burn of compressed natural gas (CNG) is applied to conventional gasoline engines, a combustion period largely increases, resulting in large combustion fluctuation and low thermal efficiency. Heterogeneous spacial air/fuel ratios also have an effect on combustion in lean burn area. By preparing a pre-chamber for a combustion chamber of high- compression ratio CNG pre-mixing SI engines to utilize premixture turbulence, rapid flame propagation is obtained in lean burn area, resulting high combustion performance. Furthermore, study was made on improvement of combustion performance in lean burn area under various compression ratios, intake pressures, pre-chamber shapes and EGR ratios. As a result, lean burn operation at high intake pressure by supercharging showed possible improvement of a thermal efficiency and expansion of inflammable limits. Higher thermal efficiency in lean burn area was also obtained by using higher compression ratios considering heat loss. Although EGR was effective in controlling NOx formed in lean burn area, strict control of both air excess rate and EGR rate was required to prevent lower thermal efficiency. 2 refs., 8 figs., 1 tab.

  9. PIV Measurements of Gas Flow Fields from Burning End

    Science.gov (United States)

    Huang, Yifei; Wu, Junzhang; Zeng, Jingsong; Tang, Darong; Du, Liang

    2017-12-01

    To study the influence of cigarette gas on the environment, it is necessary to know the cigarette gas flow fields from burning end. By using PIV technique, in order to reveal velocity characteristics of gas flow fields, the velocities of cigarette gas flow fields was analyzed with different stepping motor frequencies corresponding to suction pressures, and the trend of velocity has been given with image fitting. The results shows that the velocities of the burning end increased with suction pressures; Between velocities of the burning end and suction pressures, the relations present polynomial rule; The cigarette gas diffusion in combustion process is faster than in the smoldering process.

  10. Fluid Mechanics of Lean Blowout Precursors in Gas Turbine Combustors

    Directory of Open Access Journals (Sweden)

    T. M. Muruganandam

    2012-03-01

    Full Text Available Understanding of lean blowout (LBO phenomenon, along with the sensing and control strategies could enable the gas turbine combustor designers to design combustors with wider operability regimes. Sensing of precursor events (temporary extinction-reignition events based on chemiluminescence emissions from the combustor, assessing the proximity to LBO and using that data for control of LBO has already been achieved. This work describes the fluid mechanic details of the precursor dynamics and the blowout process based on detailed analysis of near blowout flame behavior, using simultaneous chemiluminescence and droplet scatter observations. The droplet scatter method represents the regions of cold reactants and thus help track unburnt mixtures. During a precursor event, it was observed that the flow pattern changes significantly with a large region of unburnt mixture in the combustor, which subsequently vanishes when a double/single helical vortex structure brings back the hot products back to the inlet of the combustor. This helical pattern is shown to be the characteristic of the next stable mode of flame in the longer combustor, stabilized by double helical vortex breakdown (VBD mode. It is proposed that random heat release fluctuations near blowout causes VBD based stabilization to shift VBD modes, causing the observed precursor dynamics in the combustor. A complete description of the evolution of flame near the blowout limit is presented. The description is consistent with all the earlier observations by the authors about precursor and blowout events.

  11. Evaluation of burn injuries related to liquefied petroleum gas.

    Science.gov (United States)

    Tarim, Mehmet Akin

    2014-01-01

    Liquefied petroleum gas (LPG) is a fuel that is widely used for domestic, agricultural, and industrial purposes. LPG is also commonly used in restaurants, industries, and cars; however, the home continues to be the main site for accidents. In Turkey, the increased usage of LPG as a cooking or heating fuel has resulted in many burn injuries from LPG mishaps. Between January 2000 and June 2011, 56 LPG-burned patients were compared with 112 flame-burned patients. There were no significant differences with respect to the mean age, sex, hospitalization time, and mortality in both groups. In the LPG-caused burn cases, 41 burns (73.2%) occurred at home, seven (12.5) were work-related mishaps, and eight (14.3) were associated with car accidents. The majority of the LPG burns (82%, 46 patients) resulted from a gas leak, and 18% of them were related to the failure to close LPG tubes in the patients' kitchens (10 patients). Burns to the face and neck (82 vs 67%, P = .039) and upper (62 vs 23%, P = .000) and lower (70 vs 45%, P = .002) extremities were significantly higher in LPG-caused burn cases than flame-burned cases. General awareness regarding the risk of LPG and first aid for burns appears to be lacking. The LPG delivery system should be standardized throughout countries that widely use LPG.

  12. Cellular burning in lean premixed turbulent hydrogen-air flames: Coupling experimental and computational analysis at the laboratory scale

    International Nuclear Information System (INIS)

    Day, M S; Bell, J B; Beckner, V E; Lijewski, M J; Cheng, R K; Tachibana, S

    2009-01-01

    One strategy for reducing US dependence on petroleum is to develop new combustion technologies for burning the fuel-lean mixtures of hydrogen or hydrogen-rich syngas fuels obtained from the gasification of coal and biomass. Fuel-flexible combustion systems based on lean premixed combustion have the potential for dramatically reducing pollutant emissions in transportation systems, heat and stationary power generation. However, lean premixed flames are highly susceptible to fluid-dynamical combustion instabilities making robust and reliable systems difficult to design. Low swirl burners are emerging as an important technology for meeting design requirements in terms of both reliability and emissions for next generation combustion devices. In this paper, we present simulations of a lean, premixed hydrogen flame stabilized on a laboratory-scale low swirl burner. The simulations use detailed chemistry and transport without incorporating explicit models for turbulence or turbulence/chemistry interaction. Here we discuss the overall structure of the flame and compare with experimental data. We also use the simulation data to elucidate the characteristics of the turbulent flame interaction and how this impacts the analysis of experimental measurements.

  13. Trace gas emissions from burning Florida wetlands

    Science.gov (United States)

    Cofer, Wesley R., III; Levine, Joel S.; Lebel, Peter J.; Winstead, Edward L.; Koller, Albert M., Jr.; Hinkle, C. Ross

    1990-01-01

    Measurements of biomass burn-produced trace gases were obtained using a helicopter at low altitudes above burning Florida wetlands on November 9, 1987, and from both helicopter and light-aircraft samplings on November 7, 1988. Carbon dioxide normalized emission ratios for carbon monoxide, hydrogen, methane, total nonmethane hydrocarbons, and nitrous oxide were obtained over burning graminoid wetlands consisting primarily of Spartina bakeri and Juncus roemerianus. Some interspersed scrub oak and saw palmetto were also burned. No significant differences were observed in the emission ratios determined for these gases from samples collected over flaming, mixed, and smoldering phases of combustion during the 1987 fire. Combustion-categorized differences in emission ratios were small for the 1988 fire. Combustion efficiency was relatively good (low emission ratios for reduced gases) for both fires. It is believed that the consistently low emission ratios were a unique result of graminoid wetlands fires, in which the grasses and rushes burned rapidly down to standing water and were quickly extinguished. Consequently, the efficiency of the combustion was good and the amount and duration of smoldering combustion was greatly deminished.

  14. Effects of spark plug configuration on combustion and emission characteristics of a LPG fuelled lean burn SI engine

    Science.gov (United States)

    Ravi, K.; Khan, Manazir Ahmed; Pradeep Bhasker, J.; Porpatham, E.

    2017-11-01

    Introduction of technological innovation in automotive engines in reducing pollution and increasing efficiency have been under contemplation. Gaseous fuels have proved to be a promising way to reduce emissions in Spark Ignition (SI) engines. In particular, LPG settled to be a favourable fuel for SI engines because of their higher hydrogen to carbon ratio, octane rating and lower emissions. Wide ignition limits and efficient combustion characteristics make LPG suitable for lean burn operation. But lean combustion technology has certain drawbacks like poor flame propagation, cyclic variations etc. Based on copious research it was found that location, types and number of spark plug significantly influence in reducing cyclic variations. In this work the influence of single and dual spark plugs of conventional and surface discharge electrode type were analysed. Dual surface discharge electrode spark plug enhanced the brake thermal efficiency and greatly reduced the cyclic variations. The experimental results show that rate of heat release and pressure rise was more and combustion duration was shortened in this configuration. On the emissions front, the NOx emission has increased whereas HC and CO emissions were reduced under lean condition.

  15. Constructing a unique two-phase compressibility factor model for lean gas condensates

    Energy Technology Data Exchange (ETDEWEB)

    Moayyedi, Mahmood; Gharesheikhlou, Aliashghar [Research Institute of Petroleum Industry (RIPI), Tehran (Iran, Islamic Republic of); Azamifard, Arash; Mosaferi, Emadoddin [Amirkabir University of Technology (AUT), Tehran (Iran, Islamic Republic of)

    2015-02-15

    Generating a reliable experimental model for two-phase compressibility factor in lean gas condensate reservoirs has always been demanding, but it was neglected due to lack of required experimental data. This study presents the main results of constructing the first two-phase compressibility factor model that is completely valid for Iranian lean gas condensate reservoirs. Based on a wide range of experimental data bank for Iranian lean gas condensate reservoirs, a unique two-phase compressibility factor model was generated using design of experiments (DOE) method and neural network technique (ANN). Using DOE, a swift cubic response surface model was generated for two-phase compressibility factor as a function of some selected fluid parameters for lean gas condensate fluids. The proposed DOE and ANN models were finally validated using four new independent data series. The results showed that there is a good agreement between experimental data and the proposed models. In the end, a detailed comparison was made between the results of proposed models.

  16. Constructing a unique two-phase compressibility factor model for lean gas condensates

    International Nuclear Information System (INIS)

    Moayyedi, Mahmood; Gharesheikhlou, Aliashghar; Azamifard, Arash; Mosaferi, Emadoddin

    2015-01-01

    Generating a reliable experimental model for two-phase compressibility factor in lean gas condensate reservoirs has always been demanding, but it was neglected due to lack of required experimental data. This study presents the main results of constructing the first two-phase compressibility factor model that is completely valid for Iranian lean gas condensate reservoirs. Based on a wide range of experimental data bank for Iranian lean gas condensate reservoirs, a unique two-phase compressibility factor model was generated using design of experiments (DOE) method and neural network technique (ANN). Using DOE, a swift cubic response surface model was generated for two-phase compressibility factor as a function of some selected fluid parameters for lean gas condensate fluids. The proposed DOE and ANN models were finally validated using four new independent data series. The results showed that there is a good agreement between experimental data and the proposed models. In the end, a detailed comparison was made between the results of proposed models

  17. The gas fireplace: a new burn hazard in the home.

    Science.gov (United States)

    Becker, L; Cartotto, R

    1999-01-01

    Gas fireplaces have become popular in recent years. This article presents the first reported case of a burn injury from contact with the glass front of a gas fireplace. An investigation of the surface temperature of the glass fronts of gas fireplaces was undertaken to clarify the risks posed by these units. Surface temperature measurements of the glass fronts of 3 common gas fireplace models were obtained using a thermocouple probe. Glass temperatures reached 200 degrees C within 6.5 minutes of ignition, climbing to 245 degrees C at 14 minutes after ignition. Glass temperature continued to rise beyond this point, but it could not be monitored because the adhesives securing the thermocouple probe melted. Glass temperatures of 50 degrees C were recorded at 30 minutes after the unit was shut off. The temperatures of the glass fronts of glass fireplaces are sufficient to cause cutaneous burns within seconds of contact both while the fireplace is in use and up to one half hour after it has been turned off. Current industry safety standards are not directed at the prevention of contact burns. We recommend that (1) mechanical guards be installed to create a barrier in front of the glass; (2) strict warning labels be applied to the units and ignition switches; and (3) burn prevention information be distributed with the owner's manual for these products.

  18. Enabling lean design of biomethane gas distribution grids

    NARCIS (Netherlands)

    Weidenaar, Teade; Jauregui Becker, Juan Manuel; Hoekstra, Sipke

    2015-01-01

    The Dutch gas distribution infrastructure faces several significant changes in the near future. One of the major changes is the production and injection of biomethane into the gas distribution grid. This article introduces a Design Synthesis Tool (DST) that automatically generates biomethane supply

  19. Liquefied petroleum gas cold burn sustained while refueling a car.

    Science.gov (United States)

    Scarr, Bronwyn; Mitra, Biswadev; Maini, Amit; Cleland, Heather

    2010-02-01

    There have been few cases of cold burn related to the exposure of liquid petroleum gas (LPG). We present the case of a young woman exposed to LPG while refueling her car who sustained partial thickness burns to the dorsum of her hand. Contact with LPG leaking from a pressurized system causes tissue damage because of cold injury. Immediate management of LPG is extrapolated from the management of frostbite. The increasing use of LPG mandates an awareness of prevention strategies and management principles in the setting of adverse events.

  20. Lean-rich axial stage combustion in a can-annular gas turbine engine

    Science.gov (United States)

    Laster, Walter R.; Szedlacsek, Peter

    2016-06-14

    An apparatus and method for lean/rich combustion in a gas turbine engine (10), which includes a combustor (12), a transition (14) and a combustor extender (16) that is positioned between the combustor (12) and the transition (14) to connect the combustor (12) to the transition (14). Openings (18) are formed along an outer surface (20) of the combustor extender (16). The gas turbine (10) also includes a fuel manifold (28) to extend along the outer surface (20) of the combustor extender (16), with fuel nozzles (30) to align with the respective openings (18). A method (200) for axial stage combustion in the gas turbine engine (10) is also presented.

  1. Characterization of Swirl-Venturi Lean Direct Injection Designs for Aviation Gas-Turbine Combustion

    Science.gov (United States)

    Heath, Christopher M.

    2013-01-01

    Injector geometry, physical mixing, chemical processes, and engine cycle conditions together govern performance, operability and emission characteristics of aviation gas-turbine combustion systems. The present investigation explores swirl-venturi lean direct injection combustor fundamentals, characterizing the influence of key geometric injector parameters on reacting flow physics and emission production trends. In this computational study, a design space exploration was performed using a parameterized swirl-venturi lean direct injector model. From the parametric geometry, 20 three-element lean direct injection combustor sectors were produced and simulated using steady-state, Reynolds-averaged Navier-Stokes reacting computations. Species concentrations were solved directly using a reduced 18-step reaction mechanism for Jet-A. Turbulence closure was obtained using a nonlinear ?-e model. Results demonstrate sensitivities of the geometric perturbations on axially averaged flow field responses. Output variables include axial velocity, turbulent kinetic energy, static temperature, fuel patternation and minor species mass fractions. Significant trends have been reduced to surrogate model approximations, intended to guide future injector design trade studies and advance aviation gas-turbine combustion research.

  2. Air extraction in gas turbines burning coal-derived gas

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tah-teh; Agrawal, A.K.; Kapat, J.S.

    1993-11-01

    In the first phase of this contracted research, a comprehensive investigation was performed. Principally, the effort was directed to identify the technical barriers which might exist in integrating the air-blown coal gasification process with a hot gas cleanup scheme and the state-of-the-art, US made, heavy-frame gas turbine. The guiding rule of the integration is to keep the compressor and the expander unchanged if possible. Because of the low-heat content of coal gas and of the need to accommodate air extraction, the combustor and perhaps, the flow region between the compressor exit and the expander inlet might need to be modified. In selecting a compressed air extraction scheme, one must consider how the scheme affects the air supply to the hot section of the turbine and the total pressure loss in the flow region. Air extraction must preserve effective cooling of the hot components, such as the transition pieces. It must also ensure proper air/fuel mixing in the combustor, hence the combustor exit pattern factor. The overall thermal efficiency of the power plant can be increased by minimizing the total pressure loss in the diffusers associated with the air extraction. Therefore, a study of airflow in the pre- and dump-diffusers with and without air extraction would provide information crucial to attaining high-thermal efficiency and to preventing hot spots. The research group at Clemson University suggested using a Griffith diffuser for the prediffuser and extracting air from the diffuser inlet. The present research establishes that the analytically identified problems in the impingement cooling flow are factual. This phase of the contracted research substantiates experimentally the advantage of using the Griffith diffuser with air extraction at the diffuser inlet.

  3. On the Experimental and Theoretical Investigations of Lean Partially Premixed Combustion, Burning Speed, Flame Instability and Plasma Formation of Alternative Fuels at High Temperatures and Pressures

    Science.gov (United States)

    Askari, Omid

    This dissertation investigates the combustion and injection fundamental characteristics of different alternative fuels both experimentally and theoretically. The subjects such as lean partially premixed combustion of methane/hydrogen/air/diluent, methane high pressure direct-injection, thermal plasma formation, thermodynamic properties of hydrocarbon/air mixtures at high temperatures, laminar flames and flame morphology of synthetic gas (syngas) and Gas-to-Liquid (GTL) fuels were extensively studied in this work. These subjects will be summarized in three following paragraphs. The fundamentals of spray and partially premixed combustion characteristics of directly injected methane in a constant volume combustion chamber have been experimentally studied. The injected fuel jet generates turbulence in the vessel and forms a turbulent heterogeneous fuel-air mixture in the vessel, similar to that in a Compressed Natural Gas (CNG) Direct-Injection (DI) engines. The effect of different characteristics parameters such as spark delay time, stratification ratio, turbulence intensity, fuel injection pressure, chamber pressure, chamber temperature, Exhaust Gas recirculation (EGR) addition, hydrogen addition and equivalence ratio on flame propagation and emission concentrations were analyzed. As a part of this work and for the purpose of control and calibration of high pressure injector, spray development and characteristics including spray tip penetration, spray cone angle and overall equivalence ratio were evaluated under a wide range of fuel injection pressures of 30 to 90 atm and different chamber pressures of 1 to 5 atm. Thermodynamic properties of hydrocarbon/air plasma mixtures at ultra-high temperatures must be precisely calculated due to important influence on the flame kernel formation and propagation in combusting flows and spark discharge applications. A new algorithm based on the statistical thermodynamics was developed to calculate the ultra-high temperature plasma

  4. Extending Lean and Exhaust Gas Recirculation-Dilute Operating Limits of a Modern Gasoline Direct-Injection Engine Using a Low-Energy Transient Plasma Ignition System

    Energy Technology Data Exchange (ETDEWEB)

    Sevik, James; Wallner, Thomas; Pamminger, Michael; Scarcelli, Riccardo; Singleton, Dan; Sanders, Jason

    2016-05-24

    The efficiency improvement and emissions reduction potential of lean and exhaust gas recirculation (EGR)-dilute operation of spark-ignition gasoline engines is well understood and documented. However, dilute operation is generally limited by deteriorating combustion stability with increasing inert gas levels. The combustion stability decreases due to reduced mixture flame speeds resulting in significantly increased combustion initiation periods and burn durations. A study was designed and executed to evaluate the potential to extend lean and EGR-dilute limits using a low-energy transient plasma ignition system. The low-energy transient plasma was generated by nanosecond pulses and its performance compared to a conventional transistorized coil ignition (TCI) system operated on an automotive, gasoline direct-injection (GDI) single-cylinder research engine. The experimental assessment was focused on steady-state experiments at the part load condition of 1500 rpm 5.6 bar indicated mean effective pressure (IMEP), where dilution tolerance is particularly critical to improving efficiency and emission performance. Experimental results suggest that the energy delivery process of the low-energy transient plasma ignition system significantly improves part load dilution tolerance by reducing the early flame development period. Statistical analysis of relevant combustion metrics was performed in order to further investigate the effects of the advanced ignition system on combustion stability. Results confirm that at select operating conditions EGR tolerance and lean limit could be improved by as much as 20% (from 22.7 to 27.1% EGR) and nearly 10% (from λ = 1.55 to 1.7) with the low-energy transient plasma ignition system.

  5. Experimental Combustion Dynamics Behavior of a Multi-Element Lean Direct Injection (LDI) Gas Turbine Combustor

    Science.gov (United States)

    Acosta, Waldo A.; Chang, Clarence T.

    2016-01-01

    An experimental investigation of the combustion dynamic characteristics of a research multi-element lean direct injection (LDI) combustor under simulated gas turbine conditions was conducted. The objective was to gain a better understanding of the physical phenomena inside a pressurized flametube combustion chamber under acoustically isolated conditions. A nine-point swirl venturi lean direct injection (SV-LDI) geometry was evaluated at inlet pressures up to 2,413 kPa and non-vitiated air temperatures up to 867 K. The equivalence ratio was varied to obtain adiabatic flame temperatures between 1388 K and 1905 K. Dynamic pressure measurements were taken upstream of the SV-LDI, in the combustion zone and downstream of the exit nozzle. The measurements showed that combustion dynamics were fairly small when the fuel was distributed uniformly and mostly due to fluid dynamics effects. Dynamic pressure fluctuations larger than 40 kPa at low frequencies were measured at 653 K inlet temperature and 1117 kPa inlet pressure when fuel was shifted and the pilot fuel injector equivalence ratio was increased to 0.72.

  6. Burns

    Science.gov (United States)

    A burn is damage to your body's tissues caused by heat, chemicals, electricity, sunlight, or radiation. Scalds from hot ... and gases are the most common causes of burns. Another kind is an inhalation injury, caused by ...

  7. Application of Hydrogen Assisted Lean Operation to Natural Gas-Fueled Reciprocating Engines (HALO)

    Energy Technology Data Exchange (ETDEWEB)

    Chad Smutzer

    2006-01-01

    Two key challenges facing Natural Gas Engines used for cogeneration purposes are spark plug life and high NOx emissions. Using Hydrogen Assisted Lean Operation (HALO), these two keys issues are simultaneously addressed. HALO operation, as demonstrated in this project, allows stable engine operation to be achieved at ultra-lean (relative air/fuel ratios of 2) conditions, which virtually eliminates NOx production. NOx values of 10 ppm (0.07 g/bhp-hr NO) for 8% (LHV H2/LHV CH4) supplementation at an exhaust O2 level of 10% were demonstrated, which is a 98% NOx emissions reduction compared to the leanest unsupplemented operating condition. Spark ignition energy reduction (which will increase ignition system life) was carried out at an oxygen level of 9%, leading to a NOx emission level of 28 ppm (0.13 g/bhp-hr NO). The spark ignition energy reduction testing found that spark energy could be reduced 22% (from 151 mJ supplied to the coil) with 13% (LHV H2/LHV CH4) hydrogen supplementation, and even further reduced 27% with 17% hydrogen supplementation, with no reportable effect on NOx emissions for these conditions and with stable engine torque output. Another important result is that the combustion duration was shown to be only a function of hydrogen supplementation, not a function of ignition energy (until the ignitability limit was reached). The next logical step leading from these promising results is to see how much the spark energy reduction translates into increase in spark plug life, which may be accomplished by durability testing.

  8. Lean maturity, lean sustainability

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Matthiesen, Rikke; Nielsen, Jacob

    2007-01-01

    . A framework for describing levels of lean capability is presented, based on a brief review of the literature and experiences from 12 Danish companies currently implementing lean. Although still in its emerging phase, the framework contributes to both theory and practice by describing developmental stages......Although lean is rapidly growing in popularity, its implementation is far from problem free and companies may experience difficulties sustaining long term success. In this paper, it is suggested that sustainable lean requires attention to both performance improvement and capability development...... that support lean capability development and consequently, lean sustainability....

  9. Measurement of laminar burning velocities and Markstein lengths of diluted hydrogen-enriched natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Haiyan; Jiao, Qi; Huang, Zuohua; Jiang, Deming [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Eng., Xi' an Jiaotong University (China)

    2009-01-15

    The laminar flame characteristics of natural gas-hydrogen-air-diluent gas (nitrogen/CO{sub 2}) mixtures were studied in a constant volume combustion bomb at various diluent ratios, hydrogen fractions and equivalence ratios. Both unstretched laminar burning velocity and Markstein length were obtained. The results showed that hydrogen fraction, diluent ratio and equivalence ratio have combined influence on laminar burning velocity and flame instability. The unstretched laminar burning velocity is reduced at a rate that is increased with the increase of the diluent ratio. The reduction effect of CO{sub 2} diluent gas is stronger than that of nitrogen diluent gas. Hydrogen-enriched natural gas with high hydrogen fraction can tolerate more diluent gas than that with low hydrogen fraction. Markstein length can either increase or decrease with the increase of the diluent ratio, depending on the hydrogen fraction of the fuel. (author)

  10. Spatially distributed flame transfer functions for predicting combustion dynamics in lean premixed gas turbine combustors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, K.T.; Lee, J.G.; Quay, B.D.; Santavicca, D.A. [Center for Advanced Power Generation, Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, PA (United States)

    2010-09-15

    The present paper describes a methodology to improve the accuracy of prediction of the eigenfrequencies and growth rates of self-induced instabilities and demonstrates its application to a laboratory-scale, swirl-stabilized, lean-premixed, gas turbine combustor. The influence of the spatial heat release distribution is accounted for using local flame transfer function (FTF) measurements. The two-microphone technique and CH{sup *} chemiluminescence intensity measurements are used to determine the input (inlet velocity perturbation) and the output functions (heat release oscillation), respectively, for the local flame transfer functions. The experimentally determined local flame transfer functions are superposed using the flame transfer function superposition principle, and the result is incorporated into an analytic thermoacoustic model, in order to predict the linear stability characteristics of a given system. Results show that when the flame length is not acoustically compact the model prediction calculated using the local flame transfer functions is better than the prediction made using the global flame transfer function. In the case of a flame in the compact flame regime, accurate predictions of eigenfrequencies and growth rates can be obtained using the global flame transfer function. It was also found that the general response characteristics of the local FTF (gain and phase) are qualitatively the same as those of the global FTF. (author)

  11. Emissions and efficiency of a domestic gas stove burning natural gases with various compositions

    International Nuclear Information System (INIS)

    Yungchang Ko; Tahui Lin

    2003-01-01

    The heating value of a fuel, which depends on its composition, strongly affects burner performance. Using the same gas stove to burn natural gas with various heating values is inappropriate and hazardous due to the possible occurrence of incomplete combustion (i.e. a great increase of CO emissions and/or soot formation), liftoff, flashback and inadequate heat input. In this study, we aim to assess the effects of changes in gas composition on burner performance and propose suitable design or operational factors of domestic gas stoves burning natural gas with various heating values. A single gas burner, originally designed for burning natural gas with low heating value, is adopted to investigate the effects of variations in gas composition on the burner performance. The influence of five significant parameters, including gas composition, primary aeration, gas flow rate (heat input), gas supply pressure, and loading height, on the thermal efficiency and CO emissions were reported and discussed. Using natural gas with high heating value instead of natural gas with low heating value results in a decrease in thermal efficiency (due to higher thermal input) and an increase in CO emission (caused by incomplete combustion). These problems can be significantly improved by decreasing the gas pressure to a suitable value, by enlarging the primary aeration to a favorable level, by selecting a proper thermal input, or by adjusting the optimized heating height. (Author)

  12. Conditioning of data for cyclic variation of IMEP under lean burn operation in a spark-ignition engine; Hibana tenka kikan no kihaku nensho untenji ni okeru zushi heikin yuko atsuryoku no hendo

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, K.; Urata, Y.; Yoshida, K.; Ono, t. [Honda Motor Co. Ltd., Tokyo (Japan)

    1997-07-25

    In this study, we investigated the relationship of indicated mean effective pressure (IMEP) for a spark ignition engine under lean combustion with the cyclic variation of mass fraction burned by measuring the energy release from the spark plug, intensity of the light emission from the flame and the cylinder pressure at the same time. In order to minimized an error in the initial and late combustion sages of the mass fraction burned to be obtained by cylinder pressure, spark plug energy and intensity of light emission were measured. As a result, it was found that there are three main causes of cyclic variation of IMEP. These consist of the burning speed during the initial stage of combustion, variation in the total mass fraction burned, and variation of the late burning during the late expansion stroke. Thus, we determined that there is a favorable interrelationship between the IMEPs and the corrected mass fraction burned. 13 refs., 9 figs., 1 tab.

  13. The Impact of Legislation on Gas Can- and Mattress-Related Burn Injuries.

    Science.gov (United States)

    Kellogg, Levi; Butcher, Brandon; Peek-Asa, Corinne; Wibbenmeyer, Lucy

    2018-01-01

    Burn prevention program success requires thorough evaluation of intervention outcomes. The impact of 2 engineering-specific burn prevention regulations, the Children's Gasoline Burn Prevention Act and the Standard for the Flammability of Mattress Sets, will be assessed. Records from 1997 to 2015 within the Consumer Product Safety Commission's (CPSC) National Electronic Injury Surveillance System (NEISS) were reviewed. After identifying gas can- and mattress-involved burn injuries, injury incidence was estimated by utilizing survey sampling weights associated with each record. Logistic regression, incorporating estimated injury incidence and adjusting for gender and age, was performed to test for change in injury risk following these regulations. Within NEISS, there were 493 burns involving gas cans, yielding an estimated 19,339 injuries (95% confidence interval [CI], 15,781-22,896) during the 19-year study period. The odds of a gas can burn injury after legislation decreased by 67% for children younger than 5 years (odds ratio [OR], 0.33; 95% CI, 0.16-0.66; P = 0.0018). There was no significant change in risk for persons 5 years and older (OR, 1.07; 95% CI, 0.80-1.41; P = 0.66). During the same time, there were 219 NEISS burns involving mattresses, yielding an estimated 6864 injuries (95% CI, 5071-8658). The odds of a mattress burn injury following legislation enactment decreased by 31% for all ages (OR, 0.69; 95% CI, 0.51-0.94; P = 0.02). Both regulations decreased the odds of injury in their target populations. This study demonstrates that passive interventions involving engineering standards remain a powerful tool for burn prevention and should be the focus of future efforts to improve burn care.

  14. Cyclic variations of fuel-droplet distribution during the early intake stroke of a lean-burn stratified-charge spark-ignition engine

    Energy Technology Data Exchange (ETDEWEB)

    Aleiferis, P.G. [Imperial College London, Department of Mechanical Engineering, London (United Kingdom); University College London, Department of Mechanical Engineering, London (United Kingdom); Hardalupas, Y.; Taylor, A.M.K.P. [Imperial College London, Department of Mechanical Engineering, London (United Kingdom); Ishii, K. [Honda International Technical School, Saitama (Japan); Urata, Y. [Tochigi R and D Centre, Honda R and D Co., Ltd, Tochigi (Japan)

    2005-11-01

    Lean-burn spark-ignition engines exhibit higher efficiency and lower specific emissions in comparison with stoichiometrically charged engines. However, as the air-to-fuel (A/F) ratio of the mixture is made leaner than stoichiometric, cycle-by-cycle variations in the early stages of in-cylinder combustion, and subsequent indicated mean effective pressure (IMEP), become more pronounced and limit the range of lean-burn operation. Viable lean-burn engines promote charge stratification, the mixture near the spark plug being richer than the cylinder volume averaged value. Recent work has shown that cycle-by-cycle variations in the early stages of combustion in a stratified-charge engine can be associated with variations in both the local value of A/F ratio near the spark plug around ignition timing, as well as in the volume averaged value of the A/F ratio. The objective of the current work was to identify possible sources of such variability in A/F ratio by studying the in-cylinder field of fuel-droplet distribution during the early intake stroke. This field was visualised in an optical single-cylinder 4-valve pentroof-type spark-ignition engine by means of laser-sheet illumination in planes parallel to the cylinder head gasket 6 and 10 mm below the spark plug. The engine was run with port-injected isooctane at 1500 rpm with 30% volumetric efficiency and air-to-fuel ratio corresponding to both stoichiometric firing (A/F=15, {phi} =1.0) and mixture strength close to the lean limit of stable operation (A/F=22, {phi} =0.68). Images of Mie intensity scattered by the cloud of fuel droplets were acquired on a cycle-by-cycle basis. These were studied in order to establish possible correlations between the cyclic variations in size, location and scattered-light intensity of the cloud of droplets with the respective variations in IMEP. Because of the low level of Mie intensity scattered by the droplets and because of problems related to elastic scattering on the walls of the

  15. Influence of the altitude on the burning velocity of the natural gas

    International Nuclear Information System (INIS)

    Arrieta, Andres Amell; Garcia Posada, Jorge Mario; Quilindo Valencia, Arvey; Henao Vallejo, Diego Alberto

    2004-01-01

    By the increasing use of natural gas in cities of Latin America located to high altitude, is necessary to study the effect of the altitude on the combustion, for example the burning velocity. This work is an experimental study of as it changes to the burning velocity with the altitude, being made test in sites with altitude of 40, 550, 1.020, 1.550, 2.040 and 2.550 meters. The result was that the variations are slight

  16. Fission gas release from UO2 pellet fuel at high burn-up

    International Nuclear Information System (INIS)

    Vitanza, C.; Kolstad, E.; Graziani, U.

    1979-01-01

    Analysis of in-reactor measurements of fuel center temperature and rod internal pressure at the OECD Halden Reactor Project has led to the development of an empirical fission gas release model, which is described. The model originally derived from data obtained in the low and intermediate burn-up range, appears to give good predictions for rods irradiated to high exposures as well. PIE puncturing data from seven fuel rods, operated at relatively constant powers and peak center temperatures between 1900 and 2000 0 C up to approx. 40,000 MWd/t UO 2 , did not exhibit any burn-up enhancement on the fission gas release rate

  17. Preparation Effects on the Performance of Silica-Doped Hydrous Titanium Oxide (HTO:Si)-Supported Pt Catalysts for Lean-Burn NOx Reduction by Hydrocarbons; TOPICAL

    International Nuclear Information System (INIS)

    GARDNER, TIMOTHY J.; MCLAUGHLIN, LINDA I.; MOWERY, DEBORAH L.; SANDOVAL, RONALD S.

    2002-01-01

    This report describes the development of bulk hydrous titanium oxide (HTO)- and silica-doped hydrous titanium oxide (HTO:Si)-supported Pt catalysts for lean-burn NOx catalyst applications. The effects of various preparation methods, including both anion and cation exchange, and specifically the effect of Na content on the performance of Pt/HTO:Si catalysts, were evaluated. Pt/HTO:Si catalysts with low Na content ( and lt; 0.5 wt.%) were found to be very active for NOx reduction in simulated lean-burn exhaust environments utilizing propylene as the major reductant species. The activity and performance of these low Na Pt/HTO:Si catalysts were comparable to supported Pt catalysts prepared using conventional oxide or zeolite supports. In ramp down temperature profile test conditions, Pt/HTO:Si catalysts with Na contents in the range of 3-5 wt.% showed a wide temperature window of appreciable NOx conversion relative to low Na Pt/HTO:Si catalysts. Full reactant species analysis using both ramp up and isothermal test conditions with the high Na Pt/HTO:Si catalysts, as well as diffuse reflectance FTIR studies, showed that this phenomenon was related to transient NOx storage effects associated with NaNO(sub 2)/NaNO(sub 3) formation. These nitrite/nitrate species were found to decompose and release NOx at temperatures above 300 C in the reaction environment (ramp up profile). A separate NOx uptake experiment at 275 C in NO/N(sub 2)/O(sub 2) showed that the Na phase was inefficiently utilized for NOx storage. Steady state tests showed that the effect of increased Na content was to delay NOx light-off and to decrease the maximum NOx conversion. Similar results were observed for high K Pt/HTO:Si catalysts, and the effects of high alkali content were found to be independent of the sample preparation technique. Catalyst characterization (BET surface area, H(sub 2) chemisorption, and transmission electron microscopy) was performed to elucidate differences between the HTO- and HTO

  18. Simulation of lean premixed turbulent combustion

    International Nuclear Information System (INIS)

    Bell, J; Day, M; Almgren, A; Lijewski, M; Rendleman, C; Cheng, R; Shepherd, I

    2006-01-01

    There is considerable technological interest in developing new fuel-flexible combustion systems that can burn fuels such as hydrogen or syngas. Lean premixed systems have the potential to burn these types of fuels with high efficiency and low NOx emissions due to reduced burnt gas temperatures. Although traditional Scientific approaches based on theory and laboratory experiment have played essential roles in developing our current understanding of premixed combustion, they are unable to meet the challenges of designing fuel-flexible lean premixed combustion devices. Computation, with its ability to deal with complexity and its unlimited access to data, has the potential for addressing these challenges. Realizing this potential requires the ability to perform high fidelity simulations of turbulent lean premixed flames under realistic conditions. In this paper, we examine the specialized mathematical structure of these combustion problems and discuss simulation approaches that exploit this structure. Using these ideas we can dramatically reduce computational cost, making it possible to perform high-fidelity simulations of realistic flames. We illustrate this methodology by considering ultra-lean hydrogen flames and discuss how this type of simulation is changing the way researchers study combustion

  19. Small high temperature gas-cooled reactors with innovative nuclear burning

    International Nuclear Information System (INIS)

    Liem, Peng Hong; Ismail; Sekimoto, Hiroshi

    2008-01-01

    Since the innovative concept of CANDLE (Constant Axial shape of Neutron Flux, nuclide densities and power shape During Life of Energy producing reactor) burning strategy was proposed, intensive research works have been continuously conducted to evaluate the feasibility and the performance of the burning strategy on both fast and thermal reactors. We learned that one potential application of the burning strategy for thermal reactors is for the High Temperature Gas-Cooled Reactors (HTGR) with prismatic/block-type fuel elements. Several characteristics of CANDLE burning strategy such as constant reactor characteristics during burn-up, no need for burn-up reactivity control mechanism, proportionality of core height with core lifetime, sub-criticality of fresh fuel elements, etc. enable us to design small sized HTGR with a high degree of safety easiness of operation and maintenance, and long core lifetime which are required for introducing the reactors into remote areas or developing countries with limited infrastructures and resources. In the present work, we report our evaluation results on small sized block-type HTGR designs with CANDLE burning strategy and compared with other existing small HTGR designs including the ones with pebble fuel elements, under both uranium and thorium fuel cycles. (author)

  20. Five-year epidemiology of liquefied petroleum gas-related burns.

    Science.gov (United States)

    Jin, Ronghua; Wu, Pan; Ho, Jon Kee; Wang, Xingang; Han, Chunmao

    2018-02-01

    The incidence of liquefied petroleum gas (LPG)-related burns has increased over recent years, and it has become a serious public health issue in developing countries such as India and Turkey. This paper aims to investigate the epidemiological characteristics of LPG-related burns to provide assistance and suggestions for planning prevention strategies. A 5-year retrospective study was conducted in patients with LPG-related burns admitted to the Department of Burns & Wound Care Center, Second Affiliated Hospital of Zhejiang University, College of Medicine, between 1st January 2011 and 31st December 2015. Information obtained for each patient included age, gender, education status, occupation, medical insurance, average hospital cost, length of hospital stay, monthly distribution of incidence, place of burns, mechanism of burns, extent of burns, site of burns, accompanying injuries, and treatment outcomes. For the first 4 years (2011-2014), the yearly incidence of LPG-related burns was at approximately 10% of all burns; however, in the fifth year (2015) alone, there was a surge to 26.94%. A total of 1337 burn patients were admitted during this period. Of these, 195 patients were admitted because of 169 LPG-related accidents; there were 11 accidents involving more than one victim. LPG-related burns occurred most frequently in patients aged 21-60 years (73.85%). The majority of injuries occurred from May to August (56.41%), and the most common place was home (83.08%, 162 patients). Gas leak (81.03%) was the main cause of LPG-related burns, followed by inappropriate operation (7.69%) and cooking negligence (2.05%). The mean burn area was 31.32±25.40% of TBSA. The most common sites of burns were the upper extremities (37.47%), followed by the head/face and neck (24.80%) and lower extremities (19.95%). The most common accompanying injuries included inhalation injury (23.59%), shock (8.71%), and external injury (7.18%). The average hospital stay was 22.90±19.47days (range

  1. Hydrofluoric acid burn resulting from ignition of gas from a compressed air duster.

    Science.gov (United States)

    Foster, Kevin N; Jones, LouAnn; Caruso, Daniel M

    2003-01-01

    A young female suffered burns to her hand after the ignition of gas from a compressed air duster. After debridement and dressing, the patient continued to have pain out of proportion to injury that was refractory to intravenous morphine. The material safety data sheet revealed that the chemical used was 1,1-difluoroethane. High temperatures can cause decompensation to form hydrofluoric acid. Calcium gluconate gel was applied topically to the patient's burns, which caused prompt and complete relief of her pain. A review of different compressed air duster products revealed that the main ingredient in each was a halogenated hydrocarbon. Although not considered flammable, all products have warnings regarding the possibility of ignition under various circumstances. Ignition of the gas in compressed air cleaners not only can cause flame burns, it can also cause chemical damage from exposure to hydrogen and fluoride ions. Prompt recognition and treatment is necessary to prevent severe injury.

  2. Fission gas release at high burn-up: beyond the standard diffusion model

    International Nuclear Information System (INIS)

    Landskron, H.; Sontheimer, F.; Billaux, M.R.

    2002-01-01

    At high burn-up standard diffusion models describing the release of fission gases from nuclear fuel must be extended to describe the experimental loss of xenon observed in the fuel matrix of the rim zone. Marked improvements of the prediction of integral fission gas release of fuel rods as well as of radial fission gas profiles in fuel pellets are achieved by using a saturation concept to describe fission gas behaviour not only in the pellet rim but also as an additional fission gas path in the whole pellet. (author)

  3. Reduction of NOx emissions when burning low heating value gas

    International Nuclear Information System (INIS)

    Gustafsson, R.; Oskarsson, J.; Waldheim, L.

    1993-09-01

    On the gasification of nitrogen-rich fuel the nitrogen from the fuel goes into the gas phase in the form of ammonia and hydrogen cyanide and also nitrogen containing tars. When the gas is combusted the nitrogen compounds are oxidized to a great extent to NO x and, therefore, high NO x emissions can be found on the combustion of low heating value gas produced from energy forest wood chips as is also the case with direct combustion of nitrogen rich fuels. An experimental study has been carried out where the important parameters for designing a combustion chamber for low heating value gases have been studied in order to obtain maximum reduction of NO x emissions. The effect of tar cracking using dolomite on these emissions and the effect of parameters such as the addition of steam has also been tested. The tests were carried out with energy forest wood chips with 0.3% nitrogen. The gasification was carried out in a pyrolysis reactor, operated to yield a low heating value gas, and which was coupled to a simplified gas turbine combustion chamber at atmospheric pressure. The results show that the main part of the nitrogen in the fuel is found as ammonia in the low heating value gas. With this type of gasification the conversion of fuel nitrogen to ammonia in the gas is equivalent to 500-600 mg/MJ, calculated as NO 2 . Only very low amounts of hydrogen cyanide have been noted and no nitrogen containing tar components have been found. No apparent effect of steam additions has been noted. On the other hand the distribution of air in the combustion chamber and residence time during the under stoichiometric conditions are of great importance for the NO x reduction. Depending on the air distribution the emissions of NO 2 varied between 100 and 250 mg/MJ, calculated as NO 2 . 23 refs, 11 figs, 2 tabs

  4. Simultaneous NOx and hydrocarbon emissions control for lean-burn engines using low-temperature solid oxide fuel cell at open circuit.

    Science.gov (United States)

    Huang, Ta-Jen; Hsu, Sheng-Hsiang; Wu, Chung-Ying

    2012-02-21

    The high fuel efficiency of lean-burn engines is associated with high temperature and excess oxygen during combustion and thus is associated with high-concentration NO(x) emission. This work reveals that very high concentration of NO(x) in the exhaust can be reduced and hydrocarbons (HCs) can be simultaneously oxidized using a low-temperature solid oxide fuel cell (SOFC). An SOFC unit is constructed with Ni-YSZ as the anode, YSZ as the electrolyte, and La(0.6)Sr(0.4)CoO(3) (LSC)-Ce(0.9)Gd(0.1)O(1.95) as the cathode, with or without adding vanadium to LSC. SOFC operation at 450 °C and open circuit can effectively treat NO(x) over the cathode at a very high concentration in the simulated exhaust. Higher NO(x) concentration up to 5000 ppm can result in a larger NO(x) to N(2) rate. Moreover, a higher oxygen concentration promotes NO conversion. Complete oxidation of HCs can be achieved by adding silver to the LSC current collecting layer. The SOFC-based emissions control system can treat NO(x) and HCs simultaneously, and can be operated without consuming the anode fuel (a reductant) at near the engine exhaust temperature to eliminate the need for reductant refilling and extra heating.

  5. Fission Gas Release in LWR Fuel Rods Exhibiting Very High Burn-Up

    DEFF Research Database (Denmark)

    Carlsen, H.

    1980-01-01

    Two UO2Zr BWR type test fuel rods were irradiated to a burn-up of about 38000 MWd/tUO2. After non-destructive characterization, the fission gas released to the internal free volume was extracted and analysed. The irradiation was simulated by means of the Danish fuel performance code WAFER-2, which...

  6. Shale gas: don't burn your bridges

    International Nuclear Information System (INIS)

    Dupin, L.; Casalonga, S.

    2011-01-01

    As debates take place in the French Parliament to forbid the extraction of shale in gas in France, the author outlines that, according to some experts, even though some sites might be very interesting, only a fraction of their content could be exploited. He also outlines the actual danger of this exploitation for the environment, notably because hydraulic fracturing has to be used. Although the main operators are American, French big companies possess the required know-how and are gaining experience abroad. Moreover, it seems that shale gas exploitation does not possess a significant job creation potential. The situation of different countries with respect to shale gas exploitation is briefly presented: United States, Canada, China, and Poland. The United States policy on this issue is more precisely described in a last article

  7. A multicenter study of preventable contact burns from glass fronted gas fireplaces.

    Science.gov (United States)

    Wibbenmeyer, Lucy; Gittelman, Michael A; Kluesner, Karen; Liao, Junlin; Xing, Yunfan; Faraklas, Iris; Anyan, Walter; Gamero, Chelsea; Moulton, Steven; Nederveld, Cindy; Banks, Ashley; Ryan, Colleen M; Conway, Jennifer A; Reilly, Debra A; Fish, Joel; Kelly, Charis; Peltier, George; Schwantke, Emily; Conrad, Peggie F; Caruso, Daniel M; Richey, Karen J; McCrory, Kristine; Elfar, Mohamed S A; Pittinger, Timothy; Sadie, Christine; Greenhalgh, David; Palmieri, Tina; Grossman, Peter H; Richards, Kurt M; Joyce, Teresa; Pozez, Andrea L; Savetamal, Alisa; Harrington, David T; Duncan, Kimberley; Pomerantz, Wendy J; Dillard, B Daniel

    2015-01-01

    Glass fronted gas fireplaces (GFGFs) have exterior surfaces that can reach extremely high temperatures. Burn injuries from contact with the glass front can be severe with long-term sequelae. The Consumer Product Safety Commission reported that these injuries are uncommon, whereas single-center studies indicate a much higher frequency. The purpose of this multi-institutional study was to determine the magnitude and severity of GFGF injuries in North America. Seventeen burn centers elected to participate in this retrospective chart review. Chart review identified 402 children ≤10 years of age who sustained contact burns from contact with GFGF, who were seen or admitted to the study hospitals from January 2006 to December 2010. Demographic, burn, treatment, and financial data were collected. The mean age of the study group was 16.8 ± 13.3 months. The majority suffered burns to their hands (396, 98.5%), with burns to the face being the second, much less common site (14, 3.5%). Two hundred and sixty-nine required rehabilitation therapy (66.9%). The number of GFGF injuries reported was 20 times greater than the approximately 30 injuries estimated by the Consumer Product Safety Commission's 10-year review. For the affected children, these injuries are painful, often costly and occasionally can lead to long-term sequelae. Given that less than a quarter of burn centers contributed data, the injury numbers reported herein support a need for broader safety guidelines for gas fireplaces in order to have a significant impact on future injuries.

  8. Evaluation of the physical dew point in the economizer of a combined cycle burning natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Pena, F.; Blanco, J.M. [Universidad del Pais Vasco/E.H.U. Alameda de Urquijo s/n, Bilbao (Spain). Dpto. Maquinas y Motores Termicos, Escuela Sup. de Ingenieria

    2007-08-15

    Natural gas contents a considerable percentage of hydrogen, so is obvious to expect an amount of water vapour in its combustion exhaust gases, which would raise the dew point temperature. That means a higher speed of corrosion over the whole exposed physical area, which could represent a serious risk of breakdown, especially in pressurized hot-water equipments. In this work, a new methodology for determining the physical dew point inside a economizer depending on the fuel type burned (in this case is natural gas) has been developed. The calculation of the total amount of condensed water has also been carried out as well as the localization of the area where this condensation occurs. Acid dew point has not been taken into account here although exhaust gases are acidic, due mainly to the low sulphur content which is almost undetectable when burning natural gas, but it will be performed in a later study coming soon. (author)

  9. Selective catalytic reduction of NOx in lean-burn engine exhaust over a Pt/V/MCM-41 catalyst

    International Nuclear Information System (INIS)

    Jeon, Jong Yeol; Kim, Hee Young; Woo, Seong Ihl

    2003-01-01

    The activities of Pt supported on various metal-substituted MCM-41 (V-, Ti-, Fe-, Al-, Ga-, La-, Co-, Mo-, Ce-, and Zr-MCM-41) and V-impregnated MCM-41 were investigated for the reduction of NO by C 3 H 6 . Among these catalysts, Pt supported on V-impregnated MCM-41 showed the best activity. The maximum conversion of NO into N 2 +N 2 O over this Pt/V/MCM-41 catalyst (Pt=1wt.%, V=3.8wt.%) was 73%, and this maximum conversion was sustained over a temperature range of 70C from 270 to 340C. The high activity of Pt/V/MCM-41 over a broad temperature range resulted from two additional reactions besides the reaction occurring on usual supported Pt, the reaction of NO with surface carbonaceous materials, and the reaction of NO occurring on support V-impregnated MCM-41. The former additional reaction showed an oscillation characteristic, a phenomenon in which the concentrations of parts of reactant and product gases oscillate continuously. At low temperature, some water vapor injected into the reactant gas mixture promoted the reaction occurring on usual supported Pt, whereas at high temperature, it suppressed the additional reaction related to carbonaceous materials. Five-hundred parts per million of SO 2 added to the reactant gas mixture only slightly decreased the NO conversion of Pt/V/MCM-41

  10. A comparative analysis of liquefied petroleum gas (LPG) and kerosene related burns.

    Science.gov (United States)

    Ahuja, Rajeev B; Dash, Jayant K; Shrivastava, Prabhat

    2011-12-01

    Previous studies from our department reflected a trend of decreasing incidence of burns culminating from rising income levels, which were bringing about a change in the cooking fuel in many urban households [1,2]. These studies also indicated a changing scenario of increased incidence of burns from LPG mishaps [2]. In the absence of much information on the subject we felt it rather imperative to comparatively study the pattern of burn injuries resulting from LPG and kerosene. This prospective study was conducted on the clinical database of consecutive patients admitted with burns sustained due to LPG and kerosene from 1st January 2009 to 31st May 2010 (17 months). Data recorded for each patient included; age, gender, religion, socioeconomic status, literacy level, type of family unit, marital status, type of dwelling unit, mode of injury and its exact mechanism, place of incident, level of cooking stove, extent of burns (%TBSA), presence of features of inhalation injury, number of patients affected in a single mishap, size of LPG cylinder used, length of hospital stay and mortality. Of 731 flame burn patients in this study, 395 (54%) were due to kerosene burns and 200 (27.4%) from LPG mishaps. Significantly, the majority of injuries, in both the groups, occurred in lower middle class families living as nuclear units, in a single room dwelling, without a separate kitchen. Majority of LPG burns (70.5%, 141 patients) resulted from a gas leak and 25.5% were from cooking negligence (51 patients). 50.5% of kerosene accidents were from 'stove mishaps' and 49% due to cooking negligence. In all kerosene accidents the stove was kept at floor level but in LPG group 20.6% had the stove placed on a platform. There was a slight difference in mean TBSA burns; 51% in kerosene group compared to 41.5% TBSA in LPG group. There were nine episodes in LPG group in which there were more than three burn victims admitted for treatment. Very importantly, 77% patients in LPG group were from

  11. 2-d LIF measurements of the thermo-acoustic phenomena in lean premixed flames of a gas turbine combustor

    Energy Technology Data Exchange (ETDEWEB)

    Bombach, R.; Hubschmid, W.; Inauen, A.; Kreutner, W.; Schenker, S.; Flohr, P.; Haffner, K.; Motz, C.; Paschereit, C.O.; Schuermans, B.; Zajadatz, M.

    2003-03-01

    Thermo-acoustic phenomena give rise to pressure oscillations in lean premixed flames of gas turbines at distinct frequencies characteristic of the burner design and its operation. They can lead to early materials ageing or even severe damages. Therefore, a detailed understanding of the underlying principles is fundamental for gas turbine design and improvement. In order to study the coupling between the heat release and the acoustics in the combustor as well as their feedback to the fuel/air premixing, upstream of the combustion chamber, phase-locked 2-D laser-induced fluorescence (LIF) measurements of the hydroxyl radical (OH) and acetone, respectively, have been performed. These experiments were carried out on a test rig equipped with a commercial 700 kW burner and a combustion chamber of UV transparent quartz, using a pulsed Nd:YAG/dye laser system and an intensified CCD camera for detection. Intensity variations in the integral OH LIF signal of up to {+-}10 % for one oscillation period are observed for peak sound pressure of 6 mbar and more. In addition, the phase-averaged position of the flame zone varies in axial direction, i.e. the main flow direction. The analysis shows that the observed flame motion is not only due to the acoustic motion of the gas itself, but is caused by a change of the flame velocity relative to the gas. (author)

  12. Optimalisation Of Oxide Burn-Up Enhanced For RSG-Gas Core

    International Nuclear Information System (INIS)

    Tukiran; Sembiring, Tagor Malem

    2000-01-01

    Strategy of fuel management of the RSG-Gas core has been changed from 6/1 to 5/1 pattern so the evaluation of fuel management is necessary to be done. The aim of evaluation is to look for the optimal fuel management so that the fuel can be stayed longer in the core and finally can save cost of operation. Using Batan-EQUIL-2D code did the evaluation of fuel management with 5/1 pattern. The result of evaluation is used to choose which one is more advantage without break the safety margin which is available in the Safety Analysis Report (SAR) firstly, the fuel management was calculated with core excess reactivity of 9,2% criteria. Secondly, fuel burn-up maximum of 56% criteria and the last, fuel burn-up maximum of 64% criteria. From the result of fuel management calculation of the RSG-Gas equilibrium core can be concluded that the optimal RSG-Gas equilibrium core with 5/1 pattern is if the fuel burn-up maximum 64% and the energy in a cycle of operation is 715 MWD. The fuel can be added one more step in the core without break any safety margin. It means that the RSG-Gas equilibrium core can save fuel and cost reduction

  13. Numerical Investigation of the Low-Caloric Gas Burning Process in a Bottom Burner

    Directory of Open Access Journals (Sweden)

    Redko A.

    2017-08-01

    Full Text Available The use of low-grade gases in the fuel and energy balance of enterprises makes it possible to increase the energy efficiency of technological processes. The volumes of low-grade gases (blast furnace and coke oven gases, synthesis gas of coal gasification processes, biogas, coal gas, etc. that are utilized more significant in technological processes but their calorific value are low. At the same time artificial gases contain ballast gaseous (СО2, H2O and mechanical impurities that are harmful gas impurities. Their use requires technological preparation. Thus coal methane is characterized of high humidity, coal dust and drip moisture, variable composition. Thus was effective burning of coal methane it is required the development of constructive and regime measures that ensure a stable and complete burning of gaseous fuels. In this article it is presented the results of computer simulation of a stationary turbulent diffusion flame in a restricted space in the process of burning natural gas and coal methane in a bottom burner. The calculation results contain the fields of gear, temperature, concentration of CH4‚ CO‚ H2O‚ CO2 and nitrogen oxides. The structural elements of the flame (recirculation zone, hot "dome", mixing layer and far trace are determined. It has been established that complete combustion of coal methane in a modified bottom burner is ensured and the numerical values of nitrogen oxide concentrations in the flame are consistent with the literature data.

  14. Burned gas and unburned mixture composition prediction in biodiesel-fuelled compression igniton engine

    International Nuclear Information System (INIS)

    Chuepeng, S.; Komintarachati, C.

    2009-01-01

    A prediction of burned gas and unburned mixture composition from a variety of methyl ester based bio diesel combustion in compression ignition engine, in comparison with conventional diesel fuel is presented. A free-energy minimisation scheme was used to determine mixture composition. Firstly, effects of bio diesel type were studied without exhaust gas recirculation (EGR). The combustion of the higher hydrogen-to-carbon molar ratio (H/C) bio diesel resulted in lower carbon dioxide and oxygen emissions but higher water vapour in the exhaust gases, compared to those of lower H/C ratios. At the same results also show that relative air-to-fuel ratio, that bio diesel combustion gases contain a higher amount of water vapour and a higher level of carbon dioxide compared to those of diesel. Secondly, influences of EGR (burned gas fraction) addition to bio diesel-fuelled engine on unburned mixture were simulated. For both diesel and bio diesel, the increased burned gas fraction addition to the fresh charge increased carbon dioxide and water vapour emissions while lowering oxygen content, especially for the bio diesel case. The prediction was compared with experimental results from literatures; good agreement was found. This can be considered to be a means for explaining some phenomenon occurring in bio diesel-fuelled engines. (author)

  15. Modeling and simulation of combustion dynamics in lean-premixed swirl-stabilized gas-turbine engines

    Science.gov (United States)

    Huang, Ying

    This research focuses on the modeling and simulation of combustion dynamics in lean-premixed gas-turbines engines. The primary objectives are: (1) to establish an efficient and accurate numerical framework for the treatment of unsteady flame dynamics; and (2) to investigate the parameters and mechanisms responsible for driving flow oscillations in a lean-premixed gas-turbine combustor. The energy transfer mechanisms among mean flow motions, periodic motions and background turbulent motions in turbulent reacting flow are first explored using a triple decomposition technique. Then a comprehensive numerical study of the combustion dynamics in a lean-premixed swirl-stabilized combustor is performed. The analysis treats the conservation equations in three dimensions and takes into account finite-rate chemical reactions and variable thermophysical properties. Turbulence closure is achieved using a large-eddy-simulation (LES) technique. The compressible-flow version of the Smagorinsky model is employed to describe subgrid-scale turbulent motions and their effect on large-scale structures. A level-set flamelet library approach is used to simulate premixed turbulent combustion. In this approach, the mean flame location is modeled using a level-set G-equation, where G is defined as a distance function. Thermophysical properties are obtained using a presumed probability density function (PDF) along with a laminar flamelet library. The governing equations and the associated boundary conditions are solved by means of a four-step Runge-Kutta scheme along with the implementation of the message passing interface (MPI) parallel computing architecture. The analysis allows for a detailed investigation into the interaction between turbulent flow motions and oscillatory combustion of a swirl-stabilized injector. Results show good agreement with an analytical solution and experimental data in terms of acoustic properties and flame evolution. A study of flame bifurcation from a stable

  16. Process analysis of an oxygen lean oxy-fuel power plant with co-production of synthesis gas

    International Nuclear Information System (INIS)

    Normann, Fredrik; Thunman, Henrik; Johnsson, Filip

    2009-01-01

    This paper investigates new possibilities and synergy effects for an oxy-fuel fired polygeneration scheme (transportation fuel and electricity) with carbon capture and co-firing of biomass. The proposed process has the potential to make the oxy-fuel process more effective through a sub-stoichiometric combustion in-between normal combustion and gasification, which lowers the need for oxygen within the process. The sub-stoichiometric combustion yields production of synthesis gas, which is utilised in an integrated synthesis to dimethyl ether (DME). The process is kept CO 2 neutral through co-combustion of biomass in the process. The proposed scheme is simulated with a computer model with a previous study of an oxy-fuel power plant as a reference process. The degree of sub-stoichiometric combustion, or amount of synthesis gas produced, is optimised with respect to the overall efficiency. The maximal efficiency was found at a stoichiometric ratio just below 0.6 with the efficiency for the electricity producing oxy-fuel process of 0.35 and a DME process efficiency of 0.63. It can be concluded that the proposed oxygen lean combustion process constitutes a way to improve the oxy-fuel carbon capture processes with an efficient production of DME in a polygeneration process

  17. Healthcare Lean.

    Science.gov (United States)

    Long, John C

    2003-01-01

    Lean Thinking is an integrated approach to designing, doing and improving the work of people that have come together to produce and deliver goods, services and information. Healthcare Lean is based on the Toyota production system and applies concepts and techniques of Lean Thinking to hospitals and physician practices.

  18. Impacts of prescribed burning on soil greenhouse gas fluxes in a suburban native forest of south-eastern Queensland, Australia

    Science.gov (United States)

    Zhao, Y.; Wang, Y. Z.; Xu, Z. H.; Fu, L.

    2015-11-01

    Prescribed burning is a forest management practice that is widely used in Australia to reduce the risk of damaging wildfires. Prescribed burning can affect both carbon (C) and nitrogen (N) cycling in the forest and thereby influence the soil-atmosphere exchange of major greenhouse gases, i.e. carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). To quantify the impact of a prescribed burning (conducted on 27 May 2014) on greenhouse gas exchange and the potential controlling mechanisms, we carried out a series of field measurements before (August 2013) and after (August 2014 and November 2014) the fire. Gas exchange rates were determined in four replicate plots which were burned during the combustion and in another four adjacent unburned plots located in green islands, using a set of static chambers. Surface soil properties including temperature, pH, moisture, soil C and N pools were also determined either by in situ measurement or by analysing surface 10 cm soil samples. All of the chamber measurements indicated a net sink of atmospheric CH4, with mean CH4 uptake ranging from 1.15 to 1.99 mg m-2 d-1. Prescribed burning significantly enhanced CH4 uptake as indicated by the significant higher CH4 uptake rates in the burned plots measured in August 2014. In the following 3 months, the CH4 uptake rate was recovered to the pre-burning level. Mean CO2 emission from the forest soils ranged from 2721.76 to 7113.49 mg m-2 d-1. The effect of prescribed burning on CO2 emission was limited within the first 3 months, as no significant difference was observed between the burned and the adjacent unburned plots in both August and November 2014. The CO2 emissions showed more seasonal variations, rather than the effects of prescribed burning. The N2O emission in the plots was quite low, and no significant impact of prescribed burning was observed. The changes in understory plants and litter layers, surface soil temperature, C and N substrate availability and microbial

  19. Physicochemical effects of varying fuel composition on knock characteristics of natural gas mixtures

    NARCIS (Netherlands)

    Gersen, Sander; van Essen, Martijn; van Dijk, Gerco; Levinsky, Howard

    2014-01-01

    The physicochemical origins of how changes in fuel composition affect autoignition of the end gas, leading to engine knock, are analyzed for a natural gas engine. Experiments in a lean-burn, high-speed medium-BMEP gas engine are performed using a reference natural gas with systematically varied

  20. The effect of inlet conditions on lean premixed gas turbine combustor performance

    Science.gov (United States)

    Vilayanur, Suresh Ravi

    than uniformly mixed packets. This shedding of eddies leads to an acoustic emission that can be identified in a select frequency range. The CO production is related to the swirl strength due to the proportion of products entrained into the recirculation zone. Neither lean blowout nor combustion efficiency are affected by the inlet condition variation within the range studied.

  1. Effect of water injection on nitric oxide emissions of a gas turbine combustor burning natural gas fuel

    Science.gov (United States)

    Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

    1973-01-01

    The effect of direct water injection on the exhaust gas emissions of a turbojet combustor burning natural gas fuel was investigated. The results are compared with the results from similar tests using ASTM Jet-A fuel. Increasing water injection decreased the emissions of oxides of nitrogen (NOX) and increased the emissions of carbon monoxide and unburned hydrocarbons. The greatest percentage decrease in NOX with increasing water injection was at the lowest inlet-air temperature tested. The effect of increasing inlet-air temperature was to decrease the effect of the water injection. The reduction in NOX due to water injection was almost identical to the results obtained with Jet-A fuel. However, the emission indices of unburned hydrocarbons, carbon monoxide, and percentage nitric oxide in NOX were not.

  2. Burn-Up Calculation of the Fuel Element in RSG-GAS Reactor using Program Package BATAN-FUEL

    International Nuclear Information System (INIS)

    Mochamad Imron; Ariyawan Sunardi

    2012-01-01

    Calculation of burn lip distribution of 2.96 gr U/cc Silicide fuel element at the 78 th reactor cycle using computer code program of BATAN-FUEL has been done. This calculation uses inputs such as generated power, operation time and a core assumption model of 5/1. Using this calculation model burn up for the entire fuel elements at the reactor core are able to be calculated. From the calculation it is obtained that the minimum burn up of 6.82% is RI-50 at the position of A-9, while the maximum burn up of 57.57% is RI 467 at the position of 8-7. Based on the safety criteria as specified in the Safety Analysis Report (SAR) RSG-GAS reactor, the maximum fuel burn up allowed is 59.59%. It then can be concluded that pattern that elements placement at the reactor core are properly and optimally done. (author)

  3. Reaction and Transport Effects in the Heterogeneous Systems for Lean Gas Purification.

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal; Skoblia, S.; Chyou, Y.-P.

    2017-01-01

    Roč. 71, č. 3 (2017), s. 563-577 ISSN 0366-6352 R&D Projects: GA ČR(CZ) GC14-09692J Grant - others:NSC(TW) 102WBS0300011; NSC(TW) 103-2923-E-042A-001-MY3 Institutional support: RVO:67985858 Keywords : differential reactor * gas chemisorption * alkaline solids Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.258, year: 2016

  4. Forced and self-excited oscillations in a natural gas fired lean premixed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Daesik; Park, Sung Wook

    2010-11-15

    An experimental study of the flame response in a premixed gas turbine combustor has been conducted at room temperature and under atmospheric pressure inlet conditions using natural gas. The fuel is premixed with the air upstream of a choked inlet to avoid equivalence ratio fluctuations. Therefore the observed flame response is only the result of the imposed velocity fluctuations, which are produced using a variable-speed siren. Also, a variable length combustor is designed for investigating characteristics of self-excited instabilities. Measurements are made of the velocity fluctuation in the mixing section using hot wire anemometry and of the heat release fluctuation in the combustor using chemiluminescence emission. The results are analyzed to determine the phase and gain of the flame transfer function. The results show that the gain of flame transfer function is closely associated both with inlet flow forcing conditions such as frequency and amplitude of modulation as well as the operating conditions such as equivalence ratio. In order to predict the operating conditions where the combustor goes stable or unstable at given combustor and nozzle designs, time-lag analysis was tried using convection time delay measured from the phase information of the transfer function. The model prediction was in very good agreement with the self-excited instability measurement. However, spatial heat release distribution became more significant in long flames than in short flames and also had an important influence on the system damping procedure. (author)

  5. Lean production

    OpenAIRE

    Veselková, Jana

    2011-01-01

    The goal of this Bachelor's Thesis is to describe the general principles of lean production and afterwards apply these principles in a particular company. Due to the changing conditions on the world market is among companies growing concern about such innovative business systems. The theoretical part of this work deals with the general characteristics of lean production, including their history and focus on Toyota, as the originator of most lean systems. Mentioned are also the economic aspect...

  6. A Study of Pollutant Formation from the Lean Premixed Combustion of Gaseous Fuel Alternatives to Natural Gas

    Science.gov (United States)

    Fackler, Keith Boyd, Jr.

    The goal of this research is to identify how nitrogen oxide (NO x) emissions and flame stability (blowout) are impacted by the use of fuels that are alternatives to typical pipeline natural gas. The research focuses on lean, premixed combustors that are typically used in state-of-the-art natural gas fueled systems. An idealized laboratory lean premixed combustor, specifically the jet-stirred reactor, is used for experimental data. A series of models, including those featuring detailed fluid dynamics and those focusing on detailed chemistry, are used to interpret the data and understand the underlying chemical kinetic reasons for differences in emissions between the various fuel blends. An ultimate goal is to use these data and interpretive tools to develop a way to predict the emission and stability impacts of changing fuels within practical combustors. All experimental results are obtained from a high intensity, single-jet stirred reactor (JSR). Five fuel categories are studied: (1) pure H 2, (2) process and refinery gas, including combinations of H2, CH4, C2H6, and C3H8, (3) oxygen blown gasified coal/petcoke composed of H2, CO, and CO2, (4) landfill and digester gas composed of CH4, CO2, and N2, and (5) liquified natural gas (LNG)/shale/associated gases composed of CH4, C2H6, and C3 H8. NOx measurements are taken at a nominal combustion temperature of 1800 K, atmospheric pressure, and a reactor residence time of 3 ms. This is done to focus the results on differences caused by fuel chemistry by comparing all fuels at a common temperature, pressure, and residence time. This is one of the few studies in the literature that attempts to remove these effects when studying fuels varying in composition. Additionally, the effects of changing temperature and residence time are investigated for selected fuels. At the nominal temperature and residence time, the experimental and modeling results show the following trends for NOx emissions as a function of fuel type: 1.) NOx

  7. Negotiating Lean

    DEFF Research Database (Denmark)

    Rahbek Pedersen, Esben; Muniche, Mahad

    2011-01-01

    Purpose – The purpose of this paper is to analyse how negotiations between the constituencies affect the processes and outcomes of lean projects in Danish public sector organisations. Design/methodology/approach – The paper is based on a qualitative analysis of interviews with managers...... projects in the Danish public sector. It cannot be concluded that the findings can be generalised to reflect all types of lean projects across organisational and geographical settings. Originality/value – The paper adds value to the relatively scarce literature on lean management in the public sector...... and employees who have participated in lean projects in the Danish public sector. Negotiated order theory serves as the overarching theoretical framework for the analysis. Findings – The paper concludes that the processes and outcomes of lean depend not only on the technology itself, but also the negotiation...

  8. Analysis of Japanese Articles about Suicides Involving Charcoal Burning or Hydrogen Sulfide Gas.

    Science.gov (United States)

    Nabeshima, Yoshihiro; Onozuka, Daisuke; Kitazono, Takanari; Hagihara, Akihito

    2016-10-15

    It is well known that certain types of media reports about suicide can result in imitative suicides. In the last two decades, Japan has experienced two suicide epidemics and the subsequent excessive media coverage of these events. However, the quality of the media suicide reports has yet to be evaluated in terms of the guidelines for media suicide coverage. Thus, the present study analyzed Japanese newspaper articles ( n = 4007) on suicides by charcoal burning or hydrogen sulfide gas between 11 February 2003 and 13 March 2010. The suicide reports were evaluated in terms of the extent to which they conformed to the suicide reporting guidelines. The mean violation scores were 3.06 (±0.7) for all articles, 3.2 (±0.8) for articles about suicide by charcoal burning, and 2.9 (±0.7) for articles about suicide by hydrogen sulfide ( p < 0.001). With the exception of not following several recommendations, newspaper articles about suicide have improved in quality, as defined by the recommendations for media suicide coverage. To prevent imitative suicides based on media suicide reports, individuals in the media should try not to report suicide methods and to make attempts to report the poor condition of suicide survivors.

  9. Analysis of Japanese Articles about Suicides Involving Charcoal Burning or Hydrogen Sulfide Gas

    Directory of Open Access Journals (Sweden)

    Yoshihiro Nabeshima

    2016-10-01

    Full Text Available It is well known that certain types of media reports about suicide can result in imitative suicides. In the last two decades, Japan has experienced two suicide epidemics and the subsequent excessive media coverage of these events. However, the quality of the media suicide reports has yet to be evaluated in terms of the guidelines for media suicide coverage. Thus, the present study analyzed Japanese newspaper articles (n = 4007 on suicides by charcoal burning or hydrogen sulfide gas between 11 February 2003 and 13 March 2010. The suicide reports were evaluated in terms of the extent to which they conformed to the suicide reporting guidelines. The mean violation scores were 3.06 (±0.7 for all articles, 3.2 (±0.8 for articles about suicide by charcoal burning, and 2.9 (±0.7 for articles about suicide by hydrogen sulfide (p < 0.001. With the exception of not following several recommendations, newspaper articles about suicide have improved in quality, as defined by the recommendations for media suicide coverage. To prevent imitative suicides based on media suicide reports, individuals in the media should try not to report suicide methods and to make attempts to report the poor condition of suicide survivors.

  10. Performance and emission characteristics of a turbocharged CNG engine fueled by hydrogen-enriched compressed natural gas with high hydrogen ratio

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Fanhua; Wang, Mingyue; Jiang, Long; Chen, Renzhe; Deng, Jiao; Naeve, Nashay; Zhao, Shuli [State Key Laboratory of Automotive Safety and Energy Tsinghua University, Beijing 100084 (China)

    2010-06-15

    This paper investigates the effect of high hydrogen volumetric ratio of 55% on performance and emission characteristics in a turbocharged lean burn natural gas engine. The experimental data was conducted under various operating conditions including different spark timing, excess air ratio (lambda), and manifold pressure. It is found that the addition of hydrogen at a high volumetric ratio could significantly extend the lean burn limit, improve the engine lean burn ability, decrease burn duration, and yield higher thermal efficiency. The CO, CH{sub 4} emissions were reduced and NO{sub x} emission could be kept an acceptable low level with high hydrogen content under lean burn conditions when ignition timing were optimized. (author)

  11. On the rate determining step in fission gas release from high burn-up water reactor fuel during power transients

    International Nuclear Information System (INIS)

    Walker, C.T.; Mogensen, M.

    1987-01-01

    The radial distribution of grain boundary gas in a PWR and a BWR fuel is reported. The measurements were made using a new approach involving X-ray fluorescence analysis and electron probe microanalysis. In both fuels the concentration of grain boundary gas was much higher than hitherto suspected. The gas was mainly contained in the bubble/pore structure. The factors that determined the fraction of gas released from the grains and the level of gas retention on the grain boundaries are identified and discussed. The variables involved are the local fuel stoichiometry, the amount of open porosity, the magnitude of the local compressive hydrostatic stress and the interaction of metallic precipitates with gas bubbles on the grain faces. It is concluded that under transient conditions the interlinkage of gas bubbles on the grain faces and the subsequent formation of grain edge tunnels is the rate determining step for gas release; at least when high burn-up fuel is involved. (orig.)

  12. 40 CFR 60.4325 - What emission limits must I meet for NOX if my turbine burns both natural gas and distillate oil...

    Science.gov (United States)

    2010-07-01

    ... NOX if my turbine burns both natural gas and distillate oil (or some other combination of fuels)? 60... both natural gas and distillate oil (or some other combination of fuels)? You must meet the emission... burning that fuel. Similarly, when your total heat input is greater than 50 percent distillate oil and...

  13. Spark ignition natural gas engines-A review

    International Nuclear Information System (INIS)

    Cho, Haeng Muk; He, Bang-Quan

    2007-01-01

    Natural gas is a promising alternative fuel to meet strict engine emission regulations in many countries. Natural gas engines can operate at lean burn and stoichiometric conditions with different combustion and emission characteristics. In this paper, the operating envelope, fuel economy, emissions, cycle-to-cycle variations in indicated mean effective pressure and strategies to achieve stable combustion of lean burn natural gas engines are highlighted. Stoichiometric natural gas engines are briefly reviewed. To keep the output power and torque of natural gas engines comparable to those of their gasoline or Diesel counterparts, high boost pressure should be used. High activity catalyst for methane oxidation and lean deNOx system or three way catalyst with precise air-fuel ratio control strategies should be developed to meet future stringent emission standards

  14. Model reduction of a lean NOx trap catalyst model

    NARCIS (Netherlands)

    Nauta, K.M.

    2008-01-01

    The desire to increase fuel efficiency and reduce carbon dioxide emissions of vehicles has led to an increased use of vehicles equipped with lean-burn engines, such as diesel and lean-burn gasoline engines. This type of engine uses excess oxygen when compared to the amount required to

  15. Laboratory Investigation of Trace Gas Emissions from Biomass Burning on DoD Bases

    Science.gov (United States)

    Burling, I. R.; Yokelson, R. J.; Griffith, D. W.; Roberts, J. M.; Veres, P. R.; Warneke, C.; Johnson, T. J.

    2009-12-01

    Vegetation representing fuels commonly managed with prescribed fires was collected from five DoD bases and burned under controlled conditions at the USFS Firelab in Missoula, MT. The smoke emissions were measured with a large suite of state-of-the-art instrumentation. Seventy-seven fires were conducted and the smoke composition data will improve DoD land managers’ ability to assess the impact of prescribed fires on local air quality. A key instrument used in the measurement of the gas phase species in smoke was an open-path FTIR (OP-FTIR) spectrometer, built and operated by the Universities of Montana and Wollongong. The OP-FTIR has to date detected and quantified 20 gas phase species - CO2, CO, H2O, N2O, NO2, NO, HONO, NH3, HCl, SO2, CH4, CH3OH, HCHO, HCOOH, C2H2, C2H4, CH3COOH, HCN, propylene and furan. The spectra were analyzed using a non-linear least squares fitting routine that included reference spectra recently acquired at the Pacific Northwest National Laboratories. Preliminary results from the OP-FTIR analysis are reported here. Of particular interest, gas-phase nitrous acid (HONO) was detected simultaneously by the OP-FTIR and negative-ion proton-transfer chemical ionization spectrometer (NI-PT-CIMS), with preliminary fire-integrated molar emission ratios (relative to NOx) ranging from approximately 0.03 to 0.20, depending on the vegetation type. HONO is an important precursor in the production of OH, the primary oxidizing species in the atmosphere. There existed little previous data documenting HONO emissions from either wild or prescribed fires. The non-methane organic emissions were dominated by oxygenated species, which can be further oxidized and thus involved in secondary aerosol formation. Elevated amounts of gas-phase HCl were also detected in the smoke, with the amounts varying depending on location and vegetation type.

  16. Lean Management

    OpenAIRE

    Picot, Arnold

    1994-01-01

    In this article the possibility of increase of competitiveness of the domestic enterprises by means of Lean management system is considered, and also the analysis of introduction of the mentioned system at the Russian enterprises is carried out. Besides, the key conditions necessary for successful introduction of system are presented. Lean management is a world-spread way of solving the problems, aimed at making the company competitive; it is the organized activity of staff of the company, fo...

  17. FUEL BURN-UP CALCULATION FOR WORKING CORE OF THE RSG-GAS RESEARCH REACTOR AT BATAN SERPONG

    Directory of Open Access Journals (Sweden)

    Tukiran Surbakti

    2017-12-01

    Full Text Available The neutronic parameters are required in the safety analysis of the RSG-GAS research reactor. The RSG-GAS research reactor, MTR (Material Testing Reactor type is used for research and also in radioisotope production. RSG-GAS has been operating for 30 years without experiencing significant obstacles. It is managed under strict requirements, especially fuel management and fuel burn-up calculations. The reactor is operated under the supervision of the Regulatory Body (BAPETEN and the IAEA (International Atomic Energy Agency. In this paper, the experience of managing RSG-GAS core fuels will be discussed, there are hundred possibilities of fuel placements on the reactor core and the strategy used to operate the reactor will be crucial. However, based on strict calculation and supervision, there is no incorrect placement of the fuels in the core. The calculations were performed on working core by using the WIMSD-5B computer code with ENDFVII.0 data file to generate the macroscopic cross-section of fuel and BATAN-FUEL code were used to obtain the neutronic parameter value such as fuel burn-up fractions. The calculation of the neutronic core parameters of the RSG-GAS research reactor was carried out for U3Si2-Al fuel, 250 grams of mass, with an equilibrium core strategy. The calculations show that on the last three operating cores (T90, T91, T92, all fuels meet the safety criteria and the fuel burn-up does not exceed the maximum discharge burn-up of 59%. Maximum fuel burn-up always exists in the fuel which is close to the position of control rod.

  18. Behaviour of fission gas in the rim region of high burn-up UO2 fuel pellets with particular reference to results from an XRF investigation

    International Nuclear Information System (INIS)

    Mogensen, M.; Walker, C.T.

    1999-01-01

    XRF and EPMA results for retained xenon from Battelle's high burn-up effects program are re-evaluated. The data reviewed are from commercial low enriched BWR fuel with burn-ups of 44.8-54.9 GWd/tU and high enriched PWR fuel with burn-ups from 62.5 to 83.1 GWd/tU. It is found that the high burn-up structure penetrated much deeper than initially reported. The local burn-up threshold for the formation of the high burn-up structure in those fuels with grain sizes in the normal range lay between 60 and 75 GWd/tU. The high burn-up structure was not detected by EPMA in a fuel that had a grain size of 78 μm although the local burn-up at the pellet rim had exceeded 80 GWd/tU. It is concluded that fission gas had been released from the high burn-up structure in three PWR fuel sections with burn-ups of 70.4, 72.2 and 83.1 GWd/tU. In the rim region of the last two sections at the locations where XRF indicated gas release the local burn-up was higher than 75 GWd/tU. (orig.)

  19. The atomization and burning of biofuels in the combustion chambers of gas turbine engines

    Science.gov (United States)

    Maiorova, A. I.; Vasil'ev, A. Yu; Sviridenkov, A. A.; Chelebyan, O. G.

    2017-11-01

    The present work analyzes the effect of physical properties of liquid fuels with high viscosity (including biofuels) on the spray and burning characteristics. The study showed that the spray characteristics behind devices well atomized fuel oil, may significantly deteriorate when using biofuels, until the collapse of the fuel bubble. To avoid this phenomenon it is necessary to carry out the calculation of the fuel film form when designing the nozzles. As a result of this calculation boundary curves in the coordinates of the Reynolds number on fuel - the Laplace number are built, characterizing the transition from sheet breakup to spraying. It is shown that these curves are described by a power function with the same exponent for nozzles of various designs. The swirl of air surrounding the nozzle in the same direction, as the swirl of fuel film, can significantly improve the performance of atomization of highly viscous fuel. Moreover the value of the tangential air velocity has the determining influence on the film shape. For carrying out of hot tests in aviation combustor some embodiments of liquid fuels were proved and the most preferred one was chosen. Fire tests of combustion chamber compartment at conventional fuel has shown comprehensible characteristics, in particular wide side-altars of the stable combustion. The blended biofuel application makes worse combustion stability in comparison with kerosene. A number of measures was recommended to modernize the conventional combustors when using biofuels in gas turbine engines.

  20. Lean healthcare.

    Science.gov (United States)

    Weinstock, Donna

    2008-01-01

    As healthcare organizations look for new and improved ways to reduce costs and still offer quality healthcare, many are turning to the Toyota Production System of doing business. Rather than focusing on cutting personnel and assets, "lean healthcare" looks to improve patient satisfaction through improved actions and processes.

  1. Plutonium-burn high temperature gas-cooled reactor for 3E+3S

    International Nuclear Information System (INIS)

    Okamoto, Koji

    2015-01-01

    The Nuclear Energy Development in Japan is facing a very difficult conditions after Fukushima-Daiichi NPP Accident. Nuclear Energy has strong advantages on 3E, i.e., Energy security, Economical efficiency and Environment. However, people does not believe the Safety 'S' of Nuclear Energy, now. The disadvantage of 'S' overrides the advantages of '3E'. In Nuclear Energy, 'S' is expanded into 3S, i.e., Safety, Security and Safeguards. Especially, the management of Plutonium inventory in Spent Fuel generated by the NPP operation is very important in the viewpoints of non-proliferation. The high-temperature gas cooled reactor (HTGR) is the solution of these disadvantages of '3S' in Nuclear Energy. The fuel of HTGR is composed by 1 mm spherical fuel particle, i.e., TRISO made by fuel, graphite and silicon-carbide. The silicon-carbide can confine the fission products in any conditions of fuel life cycle, i.e., during operation, accidents and disposal for 1 million years. The confinement of the radioactive materials can be confirmed by the TRISO. The HTGR core has strong negative feedback for temperature. So, the fission automatically stopped at the accidental conditions, such as loss of flow and LOCA. Also, the residual heat can be cooled by the radiation heat transfer to reactor vessel wall. The HTGR system usually has passive vessel wall cooling system. When the passive cooling system had been failed, the heat can be transferred to the land by heat conductions, and fuel does not reach the SiC broken temperature. The fission chain reaction has been stopped automatically by negative feedback, i.e., physics. The residual heat had been cooled automatically by radiation. The radioactive materials had been confined automatically by silicon-carbide. The HTGR is superior for 'S' safety. Plutonium can be burned by the HTGR. In the viewpoints of non-proliferation, the fuel should be made by YSZ-PuO 2 , stabilized buffer

  2. Effect of Machine Smoking Intensity and Filter Ventilation Level on Gas-Phase Temperature Distribution Inside a Burning Cigarette

    Directory of Open Access Journals (Sweden)

    Li Bin

    2015-01-01

    Full Text Available Accurate measurements of cigarette coal temperature are essential to understand the thermophysical and thermo-chemical processes in a burning cigarette. The last system-atic studies of cigarette burning temperature measurements were conducted in the mid-1970s. Contemporary cigarettes have evolved in design features and multiple standard machine-smoking regimes have also become available, hence there is a need to re-examine cigarette combustion. In this work, we performed systematic measurements on gas-phase temperature of burning cigarettes using an improved fine thermocouple technique. The effects of machine-smoking parameters (puff volume and puff duration and filter ventilation levels were studied with high spatial and time resolutions during single puffs. The experimental results were presented in a number of differ-ent ways to highlight the dynamic and complex thermal processes inside a burning coal. A mathematical distribution equation was used to fit the experimental temperature data. Extracting and plotting the distribution parameters against puffing time revealed complex temperature profiles under different coal volume as a function of puffing intensities or filter ventilation levels. By dividing the coal volume prior to puffing into three temperature ranges (low-temperature from 200 to 400 °C, medium-temperature from 400 to 600 °C, and high-temperature volume above 600 °C by following their development at different smoking regimes, useful mechanistic details were obtained. Finally, direct visualisation of the gas-phase temperature through detailed temperature and temperature gradient contour maps provided further insights into the complex thermo-physics of the burning coal. [Beitr. Tabakforsch. Int. 26 (2014 191-203

  3. Development of fast-burn combustion with elevated coolant temperatures for natural gas engines. Final report, May 1985-May 1990

    Energy Technology Data Exchange (ETDEWEB)

    Bruch, K.L.; Dennis, J.W.

    1990-09-01

    The overall objective of the work was to improve the state of the art in the gas fired spark ignited engine for use in a cogeneration system. Four characteristics were enhanced for cogeneration, namely, Low Pressure Gas Induction, Improved Shaft Thermal Efficiency, Low NOx Emissions, and Increased Jacket Coolant Temperature. Using Taguchi methods and statistical design of experiment methodologies, an engine design evolved that exhibited: The ability to run satisfactorily on supply gas pressure as low as 1.5 psig (goal: 1 psig); A brake specific fuel consumption as low as 6950 Btu/hp-hr (36.6% thermal efficiency) at 2 gm/hp-hr NOx (goal: 7000 acceptable, 6800 excellent with NOx no more than 2 gm/hp-hr); A jacket water coolant system (with oil cooler on the same circuit) temperature of 225 F (goal); and The ability to burn gas with Methane Number as low as 67 (goal).

  4. Survey report for fiscal 1998 on the conversion of the existing coal burning power plant to natural gas burning plant in Sakhalin State; 1998 nendo Saharinshu muke, kisetsu sekitandaki hatsuden no tennen gas daki tenkan chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The present survey is intended to discuss a modernization plan effective in reducing greenhouse effect gases for the two existing coal burning power plants in Sakhalin Island, Sakhalin State, the Federal Republic of Russia. The power plants are Sakhalinskaya Power Plant (GRES) and Yuzhno Sakalinskaya Power Plant (TETs-1). Simultaneously with converting the fuel from coal to natural gas, discussions are given on an optimal plan including introduction of the combined cycle and repowering technologies aiming at improving the thermal efficiency. Reduction in greenhouse effect gases, finance, and economy are evaluated. At the same time, verification will be given on environment improvement in Sakhalin Island, and influence on sustainable economic and social activation. The GRES modernization plan intends to build four combined cycle units each of 80 MW class to have nearly the same total capacity as the current total power generation facility capacity (315 MW). The TETs-1 modernization plan will convert the fuel for the existing boilers from coal to natural gas, modify one of the boilers whose construction is being suspended into gas burning boiler, and add gas turbines. (NEDO)

  5. Criterion for burn-up conditions in gas-cooled cryogenic current leads

    International Nuclear Information System (INIS)

    Bejan, A.; Cluss, E.M. Jr.

    1976-01-01

    Superconducting magnets are energized through helium vapour-cooled cryogenic current leads operating at high ratios of current to mass flow. The high current operation where lead temperature, runaway, and eventual burn-up are likely to occur is investigated. A simple criterion for estimating the burn-up operation conditions (current, mass flow) for a given lead geometry (cross-sectional area, length, heat exchanger area) is presented. This article stresses the role played by the available heat exchanger area in avoiding burn-up at high ratios of current to mass flow. (author)

  6. Lean consumption.

    Science.gov (United States)

    Womack, James P; Jones, Daniel T

    2005-03-01

    During the past 20 years, the real price of most consumer goods has fallen worldwide, the variety of goods and the range of sales channels offering them have continued to grow, and product quality has steadily improved. So why is consumption often so frustrating? It doesn't have to be--and shouldn't be--the authors say. They argue that it's time to apply lean thinking to the processes of consumption--to give consumers the full value they want from goods and services with the greatest efficiency and the least pain. Companies may think they save time and money by off-loading work to the consumer but, in fact, the opposite is true. By streamlining their systems for providing goods and services, and by making it easier for customers to buy and use those products and services, a growing number of companies are actually lowering costs while saving everyone time. In the process, these businesses are learning more about their customers, strengthening consumer loyalty, and attracting new customers who are defecting from less user-friendly competitors. The challenge lies with the retailers, service providers, manufacturers, and suppliers that are not used to looking at total cost from the standpoint of the consumer and even less accustomed to working with customers to optimize the consumption process. Lean consumption requires a fundamental shift in the way companies think about the relationship between provision and consumption, and the role their customers play in these processes. It also requires consumers to change the nature of their relationships with the companies they patronize. Lean production has clearly triumphed over similar obstacles in recent years to become the dominant global manufacturing model. Lean consumption, its logical companion, can't be far behind.

  7. Verification to the RSG-GAS fuel discharge burn-up using SRAC2006 module of COREBN/HIST

    International Nuclear Information System (INIS)

    J-Susilo; T-M-Sembiring; G-R-Sunaryo; M-Imron

    2018-01-01

    For 30 years operation, some of the modifications to the RSG GAS core has been done, that are changes included the type of fuel from U 3 O 8 -Al to U 3 Si 2 -Al with the same density 2.96 gU/cc, the loading pattern of standard fuel elements/fuel control elements from 6/1 & 6/2 to 5/1 pattern, and in core fuel management calculation tool has been change from IAFUEL to BATAN-FUEL. To obtain an extension of the operating license for the next 10 years, the RSG-GAS Periodic Safety Assessment Document is need to prepared. According to the Regulatory Body Chairman Regulation No. 2 2015, RSG-GAS safety assessment should be done independently. As part of this assessment the fuel discharge burn-up must be estimated. In this research, to ensure that the misposition of fuel element in the core has not occurred, the investigation to the document operating report related the fuel placement has been done. Therefore, by using 78 th to 93 rd operation data, verify of the fuel discharge burn-up of the RSG-GAS has been performed by using SRAC2006 module of COREBN/HIST. In addition, the results of these calculations are also made comparative with the operating report data that is calculated by using BATAN-FUEL. Maximum fuel discharge burn-up (57.73 % of U-235) was verified still under permissible value determined by the regulatory body (<60 % of U-235). Maximum differences value between two computer codes was about 2.12 % of U-235 (3.80 %) that is fuel at the B-7 position. Fuel discharge burn-up of RSG-GAS showed almost the same value for each the operation cycle, range of 1.52 % of U-235. So it can be concluded that the RSG-GAS core operation over the last ten years was in good fuel management performance, in accordance with the design. BATAN-FUEL has been conformed well enough with COREBN/HIST. (author)

  8. Laboratory measurements of trace gas emissions from biomass burning of fuel types from the southeastern and southwestern United States

    Science.gov (United States)

    Burling, I. R.; Yokelson, R. J.; Griffith, D. W. T.; Johnson, T. J.; Veres, P.; Roberts, J. M.; Warneke, C.; Urbanski, S. P.; Reardon, J.; Weise, D. R.; Hao, W. M.; de Gouw, J.

    2010-11-01

    Vegetation commonly managed by prescribed burning was collected from five southeastern and southwestern US military bases and burned under controlled conditions at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The smoke emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP-FTIR) spectrometer for measurement of gas-phase species. The OP-FTIR detected and quantified 19 gas-phase species in these fires: CO2, CO, CH4, C2H2, C2H4, C3H6, HCHO, HCOOH, CH3OH, CH3COOH, furan, H2O, NO, NO2, HONO, NH3, HCN, HCl, and SO2. Emission factors for these species are presented for each vegetation type burned. Gas-phase nitrous acid (HONO), an important OH precursor, was detected in the smoke from all fires. The HONO emission factors ranged from 0.15 to 0.60 g kg-1 and were higher for the southeastern fuels. The fire-integrated molar emission ratios of HONO (relative to NOx) ranged from approximately 0.03 to 0.20, with higher values also observed for the southeastern fuels. The majority of non-methane organic compound (NMOC) emissions detected by OP-FTIR were oxygenated volatile organic compounds (OVOCs) with the total identified OVOC emissions constituting 61 ± 12% of the total measured NMOC on a molar basis. These OVOC may undergo photolysis or further oxidation contributing to ozone formation. Elevated amounts of gas-phase HCl and SO2 were also detected during flaming combustion, with the amounts varying greatly depending on location and vegetation type. The fuels with the highest HCl emission factors were all located in the coastal regions, although HCl was also observed from fuels farther inland. Emission factors for HCl were generally higher for the southwestern fuels, particularly those found in the chaparral biome in the coastal regions of California.

  9. Investigation on the lean combustion performance of a hydrogen-enriched n-butanol engine

    International Nuclear Information System (INIS)

    Zhang, Bo; Ji, Changwei; Wang, Shuofeng

    2017-01-01

    Highlights: • H_2 addition avails improving thermal efficiency of n-butanol engines. • Lean burn limit of n-butanol engine is extended by H_2 addition. • H_2 addition shortens the n-butanol engine combustion duration. • HC and CO from the n-butanol engine are decreased by H_2 addition. - Abstract: n-Butanol is a feasible fuel candidate for spark-ignition engines. The current paper carried out an experiment to explore effects of hydrogen addition on further improving the performance of a n-butanol engine under the part load and lean conditions. Within the test, the engine intake pressure and speed were respectively kept at 61.5 kPa and 1400 rpm. The volumetric fractions of hydrogen in the total intake gas (hydrogen + air) were constrained at 0 and 3%, respectively. Under a certain hydrogen blending level, the global excess air ratio of in-cylinder charge which was changed from the stoichiometric to near the lean burn limit was adjusted by varying the n-butanol injection duration. The experimental results confirmed that the brake thermal efficiency was heightened and the lean burn limit was extended after the hydrogen addition. Besides, compared with the pure n-butanol combustion, the hydrogen enrichment enables the engine to gain dropped ignition delay and rapid combustion duration. Moreover, CO and HC from the pure n-butanol engine were reduced by the hydrogen addition. NOx were generally reduced when the excess air ratio was raised. This suggested that NOx from the hydrogen-enriched butanol engine could also be controlled by lean combustion.

  10. Total surface area change of Uranium dioxide fuel in function of burn-up and its impact on fission gas release during neutron irradiation for small, intermediate and high burn-up

    International Nuclear Information System (INIS)

    Szuta, M.

    2011-01-01

    In the early published papers it was observed that the fractional fission gas release from the specimen have a tendency to increase with the total surface area of the specimen - a fairy linear relationship was indicated. Moreover it was observed that the increase of total surface area during irradiation occurs in the result of connection the closed porosity with the open porosity what in turn causes the increase of fission gas release. These observations let us surmise that the process of knock-out release is the most significant process of fission gas release since its quantity is proportional to the total surface area. Review of the experiments related to the increase of total surface area in function of burn-up is presented in the paper. For very high burn-up the process of grain sub-division (polygonization) occurs under condition that the temperature of irradiated fuel lies below the temperature of grain re-crystallization. Simultaneously with the process of polygonization, the increase in local porosity and the decrease in local density in function of burn-up occurs, which leads to the increase of total surface area. It is suggested that the same processes take place in the transformed fuel as in the original fuel, with the difference that the total surface area is so big that the whole fuel can be treated as that affected by the knock-out process. This leads to explanation of the experimental data that for very high burn-up (>120 MWd/kgU) the concentration of xenon is constant. An explanation of the grain subdivision process in function of burn-up in the 'athermal' rim region in terms of total surface area, initial grain size and knock-out release is undertaken. Correlation of the threshold burn-up, the local fission gas concentration, local total surface area, initial and local grain size and burn-up in the rim region is expected. (author)

  11. Trace gas emissions to the atmosphere by biomass burning in the west African savannas

    Science.gov (United States)

    Frouin, Robert J.; Iacobellis, Samuel F.; Razafimpanilo, Herisoa; Somerville, Richard C. J.

    1994-01-01

    Savanna fires and atmospheric carbon dioxide (CO2) detection and estimating burned area using Advanced Very High Resolution Radiometer_(AVHRR) reflectance data are investigated in this two part research project. The first part involves carbon dioxide flux estimates and a three-dimensional transport model to quantify the effect of north African savanna fires on atmospheric CO2 concentration, including CO2 spatial and temporal variability patterns and their significance to global emissions. The second article describes two methods used to determine burned area from AVHRR data. The article discusses the relationship between the percentage of burned area and AVHRR channel 2 reflectance (the linear method) and Normalized Difference Vegetation Index (NDVI) (the nonlinear method). A comparative performance analysis of each method is described.

  12. Selective catalytic reduction of NO{sub x} in lean-burn engine exhaust over a Pt/V/MCM-41 catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Jong Yeol; Kim, Hee Young [Division of Advanced Chemical Technology, Korea Reasearch Institute of Chemical Technology, P.O. Box 107, Yusong, Taejon 305-600 (Korea, Republic of); Woo, Seong Ihl [Department of Chemical and Biomolecular Engineering, Center for Ultramicrochemical Process Systems, Korea Advanced Institute of Science and Technology, 373-1, Kusong-dong, Yusong-gu, Taejon, 305-701 (Korea, Republic of)

    2003-09-08

    The activities of Pt supported on various metal-substituted MCM-41 (V-, Ti-, Fe-, Al-, Ga-, La-, Co-, Mo-, Ce-, and Zr-MCM-41) and V-impregnated MCM-41 were investigated for the reduction of NO by C{sub 3}H{sub 6}. Among these catalysts, Pt supported on V-impregnated MCM-41 showed the best activity. The maximum conversion of NO into N{sub 2}+N{sub 2}O over this Pt/V/MCM-41 catalyst (Pt=1wt.%, V=3.8wt.%) was 73%, and this maximum conversion was sustained over a temperature range of 70C from 270 to 340C. The high activity of Pt/V/MCM-41 over a broad temperature range resulted from two additional reactions besides the reaction occurring on usual supported Pt, the reaction of NO with surface carbonaceous materials, and the reaction of NO occurring on support V-impregnated MCM-41. The former additional reaction showed an oscillation characteristic, a phenomenon in which the concentrations of parts of reactant and product gases oscillate continuously. At low temperature, some water vapor injected into the reactant gas mixture promoted the reaction occurring on usual supported Pt, whereas at high temperature, it suppressed the additional reaction related to carbonaceous materials. Five-hundred parts per million of SO{sub 2} added to the reactant gas mixture only slightly decreased the NO conversion of Pt/V/MCM-41.

  13. Multi-Element Lean Direct Injection Combustor Module, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a Multi-Element Lean Direct Injection, ME-LDI, Combustion concept with the following innovative features: 1. Independent, mini burning zones...

  14. New developments of the KOMPOFERM {sup registered} system. Lean gas management, SMARTFERM, double membrane roof; Neue Entwicklungen des KOMPOFERM {sup registered} -Systems. Schwachgasmanagement, SMARTFERM, Doppelmembrandach

    Energy Technology Data Exchange (ETDEWEB)

    Striewski, Sandra [KOMPOTEC Kompostierungsanlagen GmbH, Nieheim (Germany)

    2012-11-01

    The KOMPOFERM {sup registered} dry fermentation process is a mesophilic batch process for biogas production from solid biomass. The system is developed continuously for higher economic efficiency, emission reduction and environmental protection. The contribution describes the optimisations of the KOMPOFERM {sup registered} system and presents examples of its practical implementation, e.g. thermophilic process control, the KOMPOFERM {sup registered} double membrane roof for optimum gas utilisation and reduction of the lean gas volume, the KOMPOFERM {sup registered} plus process with a percolate fermenter below the fermenter tunnels, the automatic feeding system for the rotting and/or fermenter tunnels and SMARTFERM, the dry fermentation module for plants up to 4m000 Mg input. (org.) [German] Als mesophiles Batchverfahren hat sich das KOMPOFERM {sup registered} -Trockenvergaerungsverfahren zur Erzeugung von Biogas aus fester Biomasse am Markt etabliert. Das System wird stetig weiterentwickelt, um die Wirtschaftlichkeit wie auch den Emissions- und Umweltschutz der Anlagen zu verbessern. Die Optimierungen des KOMPOFERM {sup registered} -Systems werden in diesem Artikel erlaeutert und Beispiele fuer deren praktische Umsetzung gegeben, wie die thermophile Prozessfuehrung des Systems, das KOMPOFERM {sup registered} -Doppelmembrandach zur optimalen Gasnutzung und Reduzierung von Schwachgas, das KOMPOFERM {sup registered} plus-Verfahren mit einem Perkolatfermenter unterhalb der Fermentertunnel, das automatische Eintragungsgeraet fuer Rotte- und/oder Fermentertunnel sowie SMARTFERM, das Trockenfermentationsmodul fuer Anlagen bis 4.000 Mg Input. (org.)

  15. Influence of Co or Ce addition on the NOx storage and sulfur-resistance performance of the lean-burn NOx trap catalyst Pt/K/TiO{sub 2}-ZrO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zou Zhiqiang [Tianjin Key Laboratory of Applied Catalysis Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Meng, Ming, E-mail: mengm@tju.edu.cn [Tianjin Key Laboratory of Applied Catalysis Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Tsubaki, Noritatsu [Department of Applied Chemistry, School of Engineering, University of Toyama, Gofuku 3190, Toyama city, Toyama 930 8555 (Japan); He Junjun; Wang Gang; Li Xingang; Zhou Xiaoyan [Tianjin Key Laboratory of Applied Catalysis Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

    2009-10-15

    The Pt/K/TiO{sub 2}-ZrO{sub 2} catalysts promoted by Co or Ce were prepared by successive impregnation or mechanically mixing method. The influence of Co or Ce addition on the NOx storage and sulfur-resistance performance of the catalyst was investigated carefully. The techniques of XRD, FT-IR, in-situ DRIFTS, H{sub 2}-TPR and XPS were employed for catalyst characterization. The Co or Ce addition can greatly improve the NOx storage capacity of Pt/K/TiO{sub 2}-ZrO{sub 2} due to the enhanced oxidation ability and the release of more K sites. Ce addition induces higher K/Ti atomic ratio and larger NOx storage capacity as compared with Co addition. After sulfation and regeneration, the promoted catalysts shows more or less decreased NSC than Pt/K/TiO{sub 2}-ZrO{sub 2} due to the formation of more sulfates, especially for the Co-promoted catalysts, which possess better oxidation ability and facilitate the formation of large sulfates. The effect of Ce addition on Pt/K/TiO{sub 2}-ZrO{sub 2} largely depends on the addition mode. The high oxidation ability and the high K/Ti ratio of the mechanically prepared Ce-promoted catalyst make it still possess considerable NOx storage capacity (NSC) of 142 {mu}mol/g after sulfation and regeneration. With the decrease of sulfur content in fuels, the Co- and Ce-promoted catalysts possessing large NOx storage capacity, will be applicable to the purification of lean-burn NOx.

  16. Lean years

    Energy Technology Data Exchange (ETDEWEB)

    Barnet, R J

    1982-01-01

    The author attempts to take stock of five critical systems of resources: Energy, mineral resources, food, water, and human abilities. All five systems have been integrated, to an ever-increasing extent in global control systems. These control systems determine how many people, in what parts of the world, will be faced with hunger, cold, or unemployment. The author tries to find out who is in charge of these control systems, how they have come into existence, and on what strategies they are based. In the final chapter, ''Policy of survival'', the author states that the secret of survival in the lean years to come is still in the dark. Man's most fundamental desire is to be human, i.e. to be in harmony with nature both psychologically and biologically. Politics should take account of this and provide us with the means for doing what is necessary.

  17. Laboratory measurements of trace gas emissions from biomass burning of fuel types from the southeastern and southwestern United States

    Directory of Open Access Journals (Sweden)

    I. R. Burling

    2010-11-01

    Full Text Available Vegetation commonly managed by prescribed burning was collected from five southeastern and southwestern US military bases and burned under controlled conditions at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The smoke emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP-FTIR spectrometer for measurement of gas-phase species. The OP-FTIR detected and quantified 19 gas-phase species in these fires: CO2, CO, CH4, C2H2, C2H4, C3H6, HCHO, HCOOH, CH3OH, CH3COOH, furan, H2O, NO, NO2, HONO, NH3, HCN, HCl, and SO2. Emission factors for these species are presented for each vegetation type burned. Gas-phase nitrous acid (HONO, an important OH precursor, was detected in the smoke from all fires. The HONO emission factors ranged from 0.15 to 0.60 g kg−1 and were higher for the southeastern fuels. The fire-integrated molar emission ratios of HONO (relative to NOx ranged from approximately 0.03 to 0.20, with higher values also observed for the southeastern fuels. The majority of non-methane organic compound (NMOC emissions detected by OP-FTIR were oxygenated volatile organic compounds (OVOCs with the total identified OVOC emissions constituting 61 ± 12% of the total measured NMOC on a molar basis. These OVOC may undergo photolysis or further oxidation contributing to ozone formation. Elevated amounts of gas-phase HCl and SO2 were also detected during flaming combustion, with the amounts varying greatly depending on location and vegetation type. The fuels with the highest HCl emission factors were all located in the coastal regions, although HCl was also observed from fuels farther inland. Emission factors for HCl were generally higher for the southwestern fuels

  18. An overview of exhaust emissions regulatory requirements and control technology for stationary natural gas engines

    International Nuclear Information System (INIS)

    Ballard, H.N.; Hay, S.C.; Shade, W.N. Jr.

    1992-01-01

    In this paper a practical overview of stationary natural gas engine exhaust emissions control technology and trends in emissions regulatory requirements is presented. Selective and non-selective catalytic reduction and lean burn technologies are compared. Particular emphasis is focussed on implications of the Clean Air Act of 1990. Recent emissions reduction conversion kit developments and a practical approach to continuous monitoring are discussed

  19. Economic feasibility of hydrogen enrichment for reducing NOx emissions from landfill gas power generation alternatives: A comparison of the levelized cost of electricity with present strategies

    International Nuclear Information System (INIS)

    Kornbluth, Kurt; Greenwood, Jason; Jordan, Eddie; McCaffrey, Zach; Erickson, Paul A.

    2012-01-01

    Based on recent research showing that hydrogen enrichment can lower NO x emissions from landfill gas combustion below future NO x emission control standards imposed by both federal and California state regulations, an investigation was performed to compare the levelized cost of electricity of this technology with other options. In this cost study, a lean-burn reciprocating engine with no after-treatment was the baseline case to compare six other landfill gas-to-energy projects. These cases include a lean burn engine with selective catalytic reduction after treatment, a lean-burn microturbine, and four variations on an ultra-lean-burn engine utilizing hydrogen enrichment with each case using a different method of hydrogen production. Only hydrogen enrichment with an in-stream autothermal fuel reformer was shown to be potentially cost-competitive with current strategies for reaching the NO x reduction target in IC engines. - Highlights: ► Levelized cost of electricity for hydrogen enriched combustion was compared. ► Various ultra-lean-burn engines and microturbines with hydrogen were analyzed. ► Combustion with an autothermal fuel reformer was potentially cost-competitive.

  20. High-speed laser diagnostics for the study of flame dynamics in a lean premixed gas turbine model combustor

    Science.gov (United States)

    Boxx, Isaac; Arndt, Christoph M.; Carter, Campbell D.; Meier, Wolfgang

    2012-03-01

    A series of measurements was taken on two technically premixed, swirl-stabilized methane-air flames (at overall equivalence ratios of ϕ = 0.73 and 0.83) in an optically accessible gas turbine model combustor. The primary diagnostics used were combined planar laser-induced fluorescence of the OH radical and stereoscopic particle image velocimetry (PIV) with simultaneous repetition rates of 10 kHz and a measurement duration of 0.8 s. Also measured were acoustic pulsations and OH chemiluminescence. Analysis revealed strong local periodicity in the thermoacoustically self-excited (or ` noisy') flame (ϕ = 0.73) in the regions of the flow corresponding to the inner shear layer and the jet-inflow. This periodicity appears to be the result of a helical precessing vortex core (PVC) present in that region of the combustor. The PVC has a precession frequency double (at 570 Hz) that of the thermo-acoustic pulsation (at 288 Hz). A comparison of the various data sets and analysis techniques applied to each flame suggests a strong coupling between the PVC and the thermo-acoustic pulsation in the noisy flame. Measurements of the stable (` quiet') flame (ϕ = 0.83) revealed a global fluctuation in both velocity and heat-release around 364 Hz, but no clear evidence of a PVC.

  1. Internal lean practitioner's challenges in lean principles ...

    African Journals Online (AJOL)

    The approach to this paper is to answer the questions such as “how does internal management commitment impact the Lean principles?”, “how does Supply Chain Management practices impact the lean principles?”, “can Supply Chain Management practices be embedded with internal management commitment?

  2. Measurements of ultrafine particles from a gas-turbine burning biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Allouis, C.; Beretta, F.; Minutolo, P.; Pagliara, R. [Istituto di Ricerche sulla Combustione, CNR, Piazzale V. Tecchio, 80, 80125 Napoli (Italy); Sirignano, M.; Sgro, L.A.; D' Anna, A. [Dipartimento di Ingegneria Chimica, Universita di Napoli Federico II, Piazzale V. Tecchio, 80, 80125 Napoli (Italy)

    2010-04-15

    Measurements of ultrafine particles have been performed at the exhaust of a low emission microturbine for power generation. This device has been fuelled with liquid fuels, including a commercial diesel oil, a mixture of the diesel oil with a biodiesel and kerosene, and tested under different loads. Primarily attention has been focused on the measurements of the size distribution functions of the particles emitted from the system by using particle differential mobility analysis. A bimodal size distribution function of the particle emitted has been found in all the examined conditions. Burning diesel oil, the first mode of the size distribution function of the combustion-formed particles is centered at around 2-3 nm, whereas the second mode is centered at about 20-30 nm. The increase of the turbine load and the addition of 50% of biodiesel has not caused changes in the shape of size distribution of the particles. A slightly decrease of the amount of particle formed has been found. By using kerosene the amount of emitted particles increases of more than one order of magnitude. Also the shape of the size distribution function changes with the first mode shifted towards larger particles of the order of 8-10 nm but with a lower emission of larger 20-30 nm particles. Overall, in this conditions, the mass concentration of particles is increased respect to the diesel oil operation. Particle sizes measured with the diesel oil have been compared with the results on a diesel engine operated in the same power conditions and with the same fuel. Measurements have showed that the mean sizes of the formed particles do not change in the two combustion systems. However, diesel engine emits a number concentration of particles more than two orders of magnitude higher in the same conditions of power and with the same fuel. By running the engine in more premixed-like conditions, the size distribution function of the particles approaches that measured by burning kerosene in the

  3. Implementation of lean leadership

    Directory of Open Access Journals (Sweden)

    Trenkner Małgorzata

    2016-12-01

    Full Text Available The Toyota case proves that lean leadership is of critical importance for the successful implementation and permanent functioning of Lean Production System. There is no ready formula for developing Toyota style lean leadership. However, one may gain inspiration from its experience.

  4. Lean information management

    NARCIS (Netherlands)

    Hammer, D.K.

    1997-01-01

    The concept of a Lean Enterprise has proven to be extremely valuable for making companies fit for today's competitive business environment. Lean Information Management denotes the type of information management that is appropriate for such all organization. According to the paradigm of a Lean

  5. Simultaneously combining AOD and multiple trace gas measurements to identify decadal changes in urban and biomass burning aerosols

    Science.gov (United States)

    Cohen, Jason

    2017-04-01

    This work presents a methodology by which to comprehensively analyze simultaneous tropospheric measurements of AOD and associated trace gasses. It then applies this methodology by focusing over the past 11 years (2006-2016) on one of the most rapidly changing regions of the troposphere: Eastern and Southeastern Asia. The specific work presented incorporates measurements of both aerosol and related gas phase tropospheric measurements across different spectral, spatial, temporal, and passive/active sensors and properties, including: MODIS, MISR, OMI, CALIOP, and others. This new characterization reveals a trio of new information, including a time-invariant urban signal, slowly-time-varying new-urbanization signal, and a rapidly time-varying biomass burning signal. Additionally, due to the different chemical properties of the various species analyzed, analyzing the different spatial domains of the resulting products allows for further information in terms of the amounts of aerosols produced both through primary emissions as well as secondary processing. The end result is a new characterization, in space, time, and magnitude, of both anthropogenic and biomass burning aerosols. These results are then used to drive an advanced modeling system including aerosol chemistry, physics, optics, and transport, and employing an aerosol routine based on multi-modal and both externally mixed and core-shell mixing. The resulting characterization in space, time, and quantity is analyzed and compared against AERONET, NOAA, and other ground networks, with the results comparing consistently to or better than present approaches which set up net emissions separately from urban and biomass burning products. Scientifically, new source regions of emissions are identified, some of which were previously non-urbanized or found to not contain any fire hotspots. This new approach is consistent with the underlying economic and development pathways of expanding urban areas and rapid economic growth

  6. Coke burning behavior of a catalyst of ZSM-5/ZSM-11 co-crystallized zeolite in the alkylation of benzene with FCC off-gas to ethylbenzene

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yi; Zhai, Yuchun [Northeastern University, Shenyang, 110006 (P. R. China); Liu, Shenglin; Wang, Qingxia; Xu, Longya [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, P. O. Box 110, Dalian 116023 (P. R. China)

    2006-04-15

    Since the commercialization of ethylbenzene production via alkylation of benzene with the dilute ethene in FCC off-gas over a ZSM-5/ZSM-11 co-crystallized zeolite catalyst in China, the catalyst has been regenerated several times and showed good regeneration performance. During the alkylation process, the catalytic activity decreases, some of the catalyst pores are blocked and the acid centers are partly covered by coke deposition. Influence of the factors such as catalyst particle size, temperature, etc. on the burning rate of the coke was investigated by the TG technique, and a rate equation for coke burning on the ZSM-5/ZSM-11 co-crystallized catalyst was established. (author)

  7. Performance evaluation of an advanced air-fuel ratio controller on a stationary, rich-burn natural gas engine

    Science.gov (United States)

    Kochuparampil, Roshan Joseph

    The advent of an era of abundant natural gas is making it an increasingly economical fuel source against incumbents such as crude oil and coal, in end-use sectors such as power generation, transportation and industrial chemical production, while also offering significant environmental benefits over these incumbents. Equipment manufacturers, in turn, are responding to widespread demand for power plants optimized for operation with natural gas. In several applications such as distributed power generation, gas transmission, and water pumping, stationary, spark-ignited, natural gas fueled internal combustion engines (ICEs) are the power plant of choice (over turbines) owing to their lower equipment and operational costs, higher thermal efficiencies across a wide load range, and the flexibility afforded to end-users when building fine-resolution horsepower topologies: modular size increments ranging from 100 kW -- 2 MW per ICE power plant compared to 2 -- 5 MW per turbine power plant. Under the U.S. Environment Protection Agency's (EPA) New Source Performance Standards (NSPS) and Reciprocating Internal Combustion Engine National Emission Standards for Hazardous Air Pollutants (RICE NESHAP) air quality regulations, these natural gas power plants are required to comply with stringent emission limits, with several states mandating even stricter emissions norms. In the case of rich-burn or stoichiometric natural gas ICEs, very high levels of sustained emissions reduction can be achieved through exhaust after-treatment that utilizes Non Selective Catalyst Reduction (NSCR) systems. The primary operational constraint with these systems is the tight air-fuel ratio (AFR) window of operation that needs to be maintained if the NSCR system is to achieve simultaneous reduction of carbon monoxide (CO), nitrogen oxides (NOx), total hydrocarbons (THC), volatile organic compounds (VOCs), and formaldehyde (CH 2O). Most commercially available AFR controllers utilizing lambda (oxygen

  8. Maximization of Transuranic Deep-Burn in High Temperature Gas-Cooled Reactor

    International Nuclear Information System (INIS)

    Kim, Yong Hee; Kim, K. S.; Hong, S. G.; Shim, H. J.; Jo, C. K.; Lee, S. W.

    2008-03-01

    An optimization study of a single-pass transuranic (TRU) deep burn (DB) has been performed for a block-type modular helium reactor (MHR) proposed. A high-burnup TRU feed vector from light water reactors is considered. For three dimensional equilibrium cores, the performance analysis is done by using the Monte Carlo code McCARD. The core optimization is performed from the viewpoints of the core configuration, fuel management, TRISO fuel specification, and neutron spectrum. With regard to core configuration, two annular cores are investigated in terms of the neutron economy. A conventional radial shuffling scheme of fuel blocks is compared with an axial-only block-shuffling strategy in terms of the fuel bum up and core power distributions. The impact of the kernel size of the TRISO fuel is evaluated, and a diluted kernel, instead of a conventional concentrated kernel, is introduced to maximize the TRU burnup by reducing the self-shielding effects of the TRISO particles. In addition, it is shown that the core power distribution can be effectively controlled by a zoning of the packing fraction of the TRISO fuels. We also have shown that a long-cycle DB-MHR core can be designed by using a two- or three-batch fuel-reloading scheme, at the expense of only a marginal decrease of the TRU discharge bum up. Preliminary safety characteristics of a DBMHR core have been investigated in terms of the temperature coefficients and effective delayed neutron fraction. It has been found that, depending on the fuel management scheme and fuel specifications, the TRU burnup in an optimized DB-MHR core can be over 60% in a single-pass irradiation campaign. In addition, the equilibrium cycle mass balance analyses were also performed for 12 fuel cycles and the impact of TRU deep-bum on the repository was evaluated as well. Additionally, an SFR (Sodium Fast Reactor) fed with DB-MHR spent fuel were designed and characterized

  9. Thermodynamic characteristics of a low concentration methane catalytic combustion gas turbine

    International Nuclear Information System (INIS)

    Yin, Juan; Su, Shi; Yu, Xin Xiang; Weng, Yiwu

    2010-01-01

    Low concentration methane, emitted from coal mines, landfill, animal waste, etc. into the atmosphere, is not only a greenhouse gas, but also a waste energy source if not utilised. Methane is 23 times more potent than CO 2 in terms of trapping heat in the atmosphere over a timeframe of 100 years. This paper studies a novel lean burn catalytic combustion gas turbine, which can be powered with about 1% methane (volume) in air. When this technology is successfully developed, it can be used not only to mitigate the methane for greenhouse gas reduction, but also to utilise such methane as a clean energy source. This paper presents our study results on the thermodynamic characteristics of this new lean burn catalytic combustion gas turbine system by conducting thermal performance analysis of the turbine cycle. The thermodynamic data including thermal efficiencies and exergy loss of main components of the turbine system are presented under different pressure ratios, turbine inlet temperatures and methane concentrations.

  10. The effect of water injection on nitric oxide emissions of a gas turbine combustor burning ASTM Jet-A fuel

    Science.gov (United States)

    Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

    1973-01-01

    Tests were conducted to determine the effect of water injection on oxides of nitrogen (NOx) emissions of a full annular, ram induction gas turbine combustor burning ASTM Jet-A fuel. The combustor was operated at conditions simulating sea-level takeoff and cruise conditions. Water at ambient temperature was injected into the combustor primary zone at water-fuel ratios up to 2. At an inlet-air temperature of 589 K (600 F) water injection decreased the NOx emission index at a constant exponential rate: NOx = NOx (o) e to the -15 W/F power (where W/F is the water-fuel ratio and NOx(o) indicates the value with no injection). The effect of increasing combustor inlet-air temperature was to decrease the effect of the water injection. Other operating variables such as pressure and reference Mach number did not appear to significantly affect the percent reduction in NOx. Smoke emissions were found to decrease with increasing water injection.

  11. Cell formation effects on the burning speeds and flame front area of synthetic gas at high pressures and temperatures

    International Nuclear Information System (INIS)

    Askari, Omid; Elia, Mimmo; Ferrari, Matthew; Metghalchi, Hameed

    2017-01-01

    Highlights: • Effect of cell formation on burning speed and flame surface area is investigated. • A new developed non-dimensional number called cellularity factor is introduced. • Cellular burning speed and mass burning rate are calculated using differential based multi-shell model. • Flame instability is studied using thermo-diffusive and hydrodynamics effects. • Power law correlations are developed for cellular burning speeds and mass burning rates. - Abstract: Cellular burning speeds and mass burning rates of premixed syngas/oxidizer/diluent (H_2/CO/O_2/He) have been determined at high pressures and temperatures over a wide range of equivalence ratios which are at engine-relevant conditions. Working on high pressure combustion helps to reduce the pollution and increase the energy efficiency in combustion devices. The experimental facilities consisted of two spherical and cylindrical chambers. The spherical chamber, which can withstand high pressures up to 400 atm, was used to collect pressure rise data due to combustion, to calculate cellular burning speed and mass burning rate. For flame structure and instability analysis the cylindrical chamber was used to take pictures of propagating flame using a high speed CMOS camera and a schlieren photography system. A new differential based multi-shell model based on pressure rise data was used to determine the cellular burning speed and mass burning rate. In this paper, cellular burning speed and mass burning rate of H_2/CO/O_2/He mixture have been measured for a wide range of equivalence ratios from 0.6 to 2, temperatures from 400 to 750 K and pressures from 2 to 50 atm for three hydrogen concentrations of 5, 10 and 25% in the syngas. The power law correlations for cellular burning speed and mass burning rate were developed as a function of equivalence ratio, temperature and pressure. In this study a new developed parameter, called cellularity factor, which indicates the cell formation effect on flame

  12. A study of burning processes of fossil fuels in straitened conditions of furnaces in low capacity boilers by an example of natural gas

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Y. V.; Khokhlov, D. A.; Zaichenko, M. N.

    2018-03-01

    The aim of this work is to research operations of modern combined low-emission swirl burner with a capacity of 2.2 MW for fire-tube boiler type KV-GM-2.0, to ensure the effective burning of natural gas, crude oil and diesel fuel. For this purpose, a computer model of the burner and furnace chamber has been developed. The paper presents the results of numerical investigations of the burner operation, using the example of natural gas in a working load range from 40 to 100%. The basic features of processes of fuel burning in the cramped conditions of the flame tube have been identified to fundamentally differ from similar processes in the furnaces of steam boilers. The influence of the design of burners and their operating modes on incomplete combustion of fuel and the formation of nitrogen oxides has been determined.

  13. Atmospheric reactivity of hydroxyl radicals with guaiacol (2-methoxyphenol), a biomass burning emitted compound: Secondary organic aerosol formation and gas-phase oxidation products

    Science.gov (United States)

    Lauraguais, Amélie; Coeur-Tourneur, Cécile; Cassez, Andy; Deboudt, Karine; Fourmentin, Marc; Choël, Marie

    2014-04-01

    Methoxyphenols are low molecular weight semi-volatile polar aromatic compounds produced from the pyrolysis of wood lignin. The reaction of guaiacol (2-methoxyphenol) with hydroxyl radicals has been studied in the LPCA simulation chamber at (294 ± 2) K, atmospheric pressure, low relative humidity (RH reactivity of nitroguaiacols with atmospheric oxidants is probably low, we suggest using them as biomass burning emission gas tracers. The atmospheric implications of the guaiacol + OH reaction are also discussed.

  14. Performance effect of Lean

    DEFF Research Database (Denmark)

    Kristensen, Thomas Borup; Israelsen, Poul

    2016-01-01

    To understand how the practices of Lean affect performance, we tested and validated a system-wide approach using mediating relationships in a structural equation model. We used a cross-sectional survey of 200 Danish companies that indicated that they used Lean. Thus, this study is especially...... relevant to Denmark, but the approach is empirically more generalizable. We show that the effect of Lean standardized flow production practices on performance is mediated by analytical continuous improvement empowerment practices and by delegation of decision rights practices. Thus, standardized flow...... of decision rights. The paper provides evidence that supports the view that middle managers’ actions further enhance performance in Lean companies. The right Lean behavior by middle managers increases the level of analytical continuous improvement empowerment. In total, high-performing Lean companies...

  15. First results from a large, multi-platform study of trace gas and particle emissions from biomass burning

    Science.gov (United States)

    I. R. Burling; R. J. Yokelson; S. K. Akagi; T. J. Johnson; D. W. Griffith; Shawn Urbanski; J. W. Taylor; J. S. Craven; G. R. McMeeking; J. M. Roberts; C. Warneke; P. R. Veres; J. A. de Gouw; J. B. Gilman; W. C. Kuster; WeiMin Hao; D. Weise; H. Coe; J. Seinfeld

    2010-01-01

    We report preliminary results from a large, multi-component study focused on North American biomass burning that measured both initial emissions and post-emission processing. Vegetation types burned were from the relatively less-studied temperate region of the US and included chaparral, oak savanna, and mixed conifer forest from the southwestern US, and pine understory...

  16. LEAN dig ikke tilbage

    DEFF Research Database (Denmark)

    Weirsøe, Mathilde

    2011-01-01

    Fit, slankere, hurtigst. Lean-konceptet ruller ind over de offentlige institutioner, hvor det skal trimme og effektivisere arbejdsprocesser. Men hvor er den maksimale grænse for effektivitet? Er der et ’tipping point’, hvor Lean ikke længere motiverer, men snarere udmatter......Fit, slankere, hurtigst. Lean-konceptet ruller ind over de offentlige institutioner, hvor det skal trimme og effektivisere arbejdsprocesser. Men hvor er den maksimale grænse for effektivitet? Er der et ’tipping point’, hvor Lean ikke længere motiverer, men snarere udmatter...

  17. Enhanced levels of atmospheric low-molecular weight monocarboxylic acids in gas and particulates over Mt. Tai, North China, during field burning of agricultural wastes

    Science.gov (United States)

    Mochizuki, Tomoki; Kawamura, Kimitaka; Nakamura, Shinnosuke; Kanaya, Yugo; Wang, Zifa

    2017-12-01

    To understand the source and atmospheric behaviour of low molecular weight monocarboxylic acids (monoacids), gaseous (G) and particulate (P) organic acids were collected at the summit of Mt. Tai in the North China Plain (NCP) during field burning of agricultural waste (wheat straw). Particulate organic acids were collected with neutral quartz filter whereas gaseous organic acids were collected with KOH-impregnated quartz filter. Normal (C1-C10), branched (iC4-iC6), hydroxy (lactic and glycolic), and aromatic (benzoic) monoacids were determined with a capillary gas chromatography employing p-bromophenacyl esters. We found acetic acid as the most abundant gas-phase species whereas formic acid is the dominant particle-phase species. Concentrations of formic (G/P 1 570/1 410 ng m-3) and acetic (3 960/1 120 ng m-3) acids significantly increased during the enhanced field burning of agricultural wastes. Concentrations of formic and acetic acids in daytime were found to increase in both G and P phases with those of K+, a field-burning tracer (r = 0.32-0.64). Primary emission and secondary formation of acetic acid is linked with field burning of agricultural wastes. In addition, we found that particle-phase fractions (Fp = P/(G + P)) of formic (0.50) and acetic (0.31) acids are significantly high, indicating that semi-volatile organic acids largely exist as particles. Field burning of agricultural wastes may play an important role in the formation of particulate monoacids in the NCP. High levels (917 ng m-3) of particle-phase lactic acid, which is characteristic of microorganisms, suggest that microbial activity associated with terrestrial ecosystem significantly contributes to the formation of organic aerosols.

  18. An experimental study of the velocity-forced flame response of a lean-premixed multi-nozzle can combustor for gas turbines

    Science.gov (United States)

    Szedlmayer, Michael Thomas

    The velocity forced flame response of a multi-nozzle, lean-premixed, swirl-stabilized, turbulent combustor was investigated at atmospheric pressure. The purpose of this study was to analyze the mechanisms that allowed velocity fluctuations to cause fluctuations in the rate of heat release in a gas turbine combustor experiencing combustion instability. Controlled velocity fluctuations were introduced to the combustor by a rotating siren device which periodically allowed the air-natural gas mixture to flow. The velocity fluctuation entering the combustor was measured using the two-microphone method. The resulting heat release rate fluctuation was measured using CH* chemiluminescence. The global response of the flame was quantified using the flame transfer function with the velocity fluctuation as the input and the heat release rate fluctuation as the output. Velocity fluctuation amplitude was initially maintained at 5% of the inlet velocity in order to remain in the linear response regime. Flame transfer function measurements were acquired at a wide range of operating conditions and forcing frequencies. The selected range corresponds to the conditions and instability frequencies typical of real gas turbine combustors. Multi-nozzle flame transfer functions were found to bear a qualitative similarity to the single-nozzle flame transfer functions in the literature. The flame transfer function gain exhibited alternating minima and maxima while the phase decreased linearly with increasing forcing frequency. Several normalization techniques were applied to all flame transfer function data in an attempt to collapse the data into a single curve. The best collapse was found to occur using a Strouhal number which was the ratio of the characteristic flame length to the wavelength of the forced disturbance. Critical values of Strouhal number are used to predict the shedding of vortical structures in shear layers. Because of the collapse observed when the flame transfer functions

  19. Penetration of natural gas in industrial processes for direct burning: the case of ceramics, cement and glass industries; Penetracao do gas natural em processos industriais de queima direta: caso das industrias ceramica, cimento e vidro

    Energy Technology Data Exchange (ETDEWEB)

    Berni, Mauro Donizeti; Leite, Alvaro A. Furtado [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Dorileo, Ivo Leandro [Universidade Federal do Mato Grosso (NIEPE/UFMT), Cuiaba, MT (Brazil). Nucleo Interdisciplinar de Estudos em Planejamento Energetico; Bajay, Sergio Valdir [Universidade estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Dept. de Energia], e-mail: bajay@fem.unicamp.com.br

    2008-07-01

    Industrial sector can use the natural gas (NG) as raw material, as fuel and in co-generation. The NG as fuel is used, predominantly, to produce heat in the Brazilian industries. That rate, both main forms of industrial use of the NG are its direct burning in kilns - when the direct contact is had with the product - and the supply of process heat through boilers, for instance. Direct burning is used in the ceramic, cement and glass industries. This work discuss the penetration opportunity of the NG in the direct burning regarding the fuel oil and other energy that it can substitute, the environmental effects and the co-generation possibilities in each one of the analyzed industrial blanches in this work. (author)

  20. Lean Production : Werkzeuge zur Realisierung

    OpenAIRE

    Binner, Hartmut F.

    2008-01-01

    INHALT: l. Einleitung und Standortbestimmung 2. Japanische Wertvorstellungen 3. Inhalte der Lean Production 4. Fertigungssegmentierung 5. Informationsmanagement mit CIM- und Logistik-Komponenten 6. Logistikgerechte Strukturen der Lean Production 7. Realisierung der Lean Production 8. Zusammenfassung

  1. Lean and Information Technology Toolkit

    Science.gov (United States)

    The Lean and Information Technology Toolkit is a how-to guide which provides resources to environmental agencies to help them use Lean Startup, Lean process improvement, and Agile tools to streamline and automate processes.

  2. Moving on - beyond lean thinking

    OpenAIRE

    Koskela, Lauri

    2004-01-01

    Lean Thinking is currently often positioned as the underlying theory of lean production among practitioners and academics, although its originators, Womack and Jones, seem not to have presented it as a theory. This paper endeavors to analyze whether Lean Thinking can be viewed as a theory of lean production. For this purpose, a critical assessment of Lean Thinking is carried out. Lean Thinking is argued to lack an adequate conceptualization of production, which has led to imprecise concepts, ...

  3. lean-ISD.

    Science.gov (United States)

    Wallace, Guy W.

    2001-01-01

    Explains lean instructional systems design/development (ISD) as it relates to curriculum architecture design, based on Japan's lean production system. Discusses performance-based systems; ISD models; processes for organizational training and development; curriculum architecture to support job performance; and modular curriculum development. (LRW)

  4. Healthy Lean Through HRD

    DEFF Research Database (Denmark)

    Jørgensen, Frances

    2008-01-01

    The paper reports on findings from the initial, exploratory phase of a longitudinal research study aimed at developing a framework for implementing lean while ensuring employee well-being. Data from observations and in-depth dialogues with persons involved in lean implementation, along...

  5. LEAN and energy efficiency; Lean og energieffektivisering

    Energy Technology Data Exchange (ETDEWEB)

    Jespersen, Per T; Vesterager Christensen, D; Andersen, Hans [Teknologisk Institut, Energi og Klima, Taastrup (Denmark); Dam Wied, M; Dam, M [NRGi Raadgivning, Aarhus (Denmark); Thorndahl, M [Horsens Kommune, Horsens (Denmark); Weldingh, P [Lokal Energi, Viby J. (Denmark); Maagoee, P; Kristensen, Kenneth T [Viegand og Maagoee, Copenhagen (Denmark); Kirketerp Friis, A [Novozymes, Bagsvaerd (Denmark)

    2010-03-15

    By means of theoretical reports and three specific cases, the project showed how Lean principles can improve energy consulting efficiency, thus making it easier for end-users and energy consultants to record and document energy savings achieved. The three cases documented various types of extra benefits of integrating energy efficiency improvement in Lean processes. As a result of process optimisation, one manufacturing company successfully reduced both staffing and energy consumption, thus making production in Denmark competitive with out-sourced production in Asia. (LN)

  6. Diccionario Lean Manufacturing

    OpenAIRE

    Muñoz Ellner, Sarah María

    2016-01-01

    El Diccionario Bilingüe de Lean Manufacturing pretende ser un instrumento de apoyo a todo aquel que tenga la responsabilidad de planear, ejecutar o simplemente algún interés con las actividades de Lean Manufacturing, aportando así también conceptos claros tanto en castellano como en inglés, con el fin de entender de forma integral el alcance mismo que puede llegar a tener dicha filosofía, al igual que se proporcionara una serie de siglas y herramientas para la implementación del Lean Manufact...

  7. Développement d'un moteur 4-soupapes fonctionnant en mélange dilué. Une nouvelle approche basée sur l'optimisation de l'aérodynamique interne Application of Flow Field Optimization to Lean Burn Engine Development. A New Approach Based on Internal Flow Field Optimization

    Directory of Open Access Journals (Sweden)

    Henriot S.

    2006-11-01

    entre 0,60 et 0,70 suivant la charge et le régime. La diminution des émissions d'oxydes d'azote qui en résulte atteint en moyenne sur des points représentatifs du cycle ECE15 74 % par rapport au fonctionnement à la stoechiométrie. Enfin, des essais avec recyclage des gaz d'échappement ont démontré le potentiel de la solution optimisée d'un point de vue aérodynamique à tout mode de fonctionnement en mélange dilué. The constraints that must be accounted for inbuilding a new engine are increasing. It is necessary to contend with user demands for performance, while improving efficiency, limiting pollutant emissions and reducing knock sensitivity. Given the number of parameters to be taken into account, the response to these demands would require large investments in time and resources if conventional development methods (which usually follow an empirical approach were applied. The purpose of this research supported by Groupement Scientifique Moteur (GSM was to design a lean-burn sparkignition engine with the object of reducing pollutant emissions and fuel consumption. We try to develop a promising new approach that follows a scientific methodology based in particular on the use of predictive computer codes. The objective of this project is to design an engine that runs on a lean or possibly dilute mixture that will meet European pollution regulations. This lean-burn solution, combined with oxidation catalysis, is considered as an alternative to threeway catalysis, which imposes operation at stoichiometry. The original configuration is a 4-valve engine. One of the advantages this engine offers is great flexibility in changing the inlet conditions. This provides a way of optimizing internal fluid motion, which turns out to be a determining factor in the ability to operate with a lean or dilute mixture. The operation of an engine with a lean or dilute mixture results in substantially reducing nitrogen oxide (NOx emissions, virtually eliminating carbon dioxide (CO

  8. Sector Tests of a Low-NO(sub x), Lean, Direct- Injection, Multipoint Integrated Module Combustor Concept Conducted

    Science.gov (United States)

    Tacina, Robert R.; Wey, Chang-Lie; Laing, Peter; Mansour, Adel

    2002-01-01

    The low-emissions combustor development described is directed toward advanced high pressure aircraft gas-turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low power conditions. Low-NOx combustors can be classified into rich-burn and lean-burn concepts. Lean-burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) concepts. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibility of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone, and thus, it does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, good atomization is necessary and the fuel must be mixed quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP. The LDI concept described is a multipoint fuel injection/multiburning zone concept. Each of the multiple fuel injectors has an air swirler associated with it to provide quick mixing and a small recirculation zone for burning. The multipoint fuel injection provides quick, uniform mixing and the small multiburning zones provide for reduced burning residence time, resulting in low NOx formation. An integrated-module approach was used for the construction where chemically etched laminates, diffusion bonded together, combine the fuel injectors, air swirlers, and fuel manifold into a single element. The multipoint concept combustor was demonstrated in a 15 sector test. The configuration tested had 36

  9. Lean og arbejdsmiljø

    DEFF Research Database (Denmark)

    Jensen, Kenneth

    Bogen tager udgangspunkt i en undersøgelse af 10 private og offentlige virksomheders erfaringer med lean. Undersøgelsen viser at der ikke findes entydige sammenhænge mellem lean og det psykosociale arbejdsmiljø. Bogen forholder sig til sammenhængen mellem lean og ledelse, lean og medarbejderens...... rolle, lean og lean og forandringsprocessen. Bogen kommer desuden med anbefalinger til hvorledes virksomheden kan gribe dialogen an for at opnå et godt lean forløb der inddrager hensynet til og effekterne af et godt psykosocialt arbejdsmiljø....

  10. Orchestrating Lean Implementation

    DEFF Research Database (Denmark)

    Riis, Jens Ove; Mikkelsen, Hans; Andersen, Jesper Rank

    2008-01-01

    The notion of Lean Manufacturing is not merely confined to a set of well defined techniques, but represents a broad approach to managing a company. Working with lean entails many aspects, such as production planning and control, production engineering, product development, supply chain......, and organizational issues. To become effective, many functional areas and departments must be involved. At the same time companies are embedded in a dynamic environment. The aim of the paper is to propose a comprehensive approach to better implementation of lean initiatives, based on two empirical studies. The paper...... will discuss how a concerted effort can be staged taking into account the interdependencies among individual improvement initiatives. The notion of orchestration will be introduced, and several means for orchestration will be presented. Critical behavioral issues for lean implementation will be discussed....

  11. Lean Government Methods Guide

    Science.gov (United States)

    This Guide focuses primarily on Lean production, which is an organizational improvement philosophy and set of methods that originated in manufacturing but has been expanded to government and service sectors.

  12. Lean Enterprise Value Phase

    National Research Council Canada - National Science Library

    Shields, John T

    2005-01-01

    ... using a philosophy called "lean." LAl's mission is to research, develop, and promulgate practices, tools, and knowledge that enable and accelerate the envisioned transformation of the greater US aerospace enterprise through people and processes...

  13. Estimates of global, regional, and national annual CO{sub 2} emissions from fossil-fuel burning, hydraulic cement production, and gas flaring: 1950--1992

    Energy Technology Data Exchange (ETDEWEB)

    Boden, T.A.; Marland, G. [Oak Ridge National Lab., TN (United States); Andres, R.J. [University of Alaska, Fairbanks, AK (United States). Inst. of Northern Engineering

    1995-12-01

    This document describes the compilation, content, and format of the most comprehensive C0{sub 2}-emissions database currently available. The database includes global, regional, and national annual estimates of C0{sub 2} emissions resulting from fossil-fuel burning, cement manufacturing, and gas flaring in oil fields for 1950--92 as well as the energy production, consumption, and trade data used for these estimates. The methods of Marland and Rotty (1983) are used to calculate these emission estimates. For the first time, the methods and data used to calculate CO, emissions from gas flaring are presented. This C0{sub 2}-emissions database is useful for carbon-cycle research, provides estimates of the rate at which fossil-fuel combustion has released C0{sub 2} to the atmosphere, and offers baseline estimates for those countries compiling 1990 C0{sub 2}-emissions inventories.

  14. Burning issues

    Energy Technology Data Exchange (ETDEWEB)

    Ashmore, C.

    1998-10-01

    Coal is world`s most abundant source of energy. Turning this potential pollutant into a clean, cost-effective fuel for power production has become a matter for global concern. Some problems and their solutions are highlighted in this article. Environmental problems caused by the giant Mae Moh plant in Thailand were overcome with an extensive retrofit programme that included flue gas desulfurisation systems. For new and smaller coal-fuelled plant, boilers using circulating fluidised bed (CFB) technology provide a cost effective and efficient system which meets environmental standards. A large independent power plant at Colver, Pennsylvania, USA uses CFB technology to burn bituminous gob. AMM and Alstom can provide turnkey packages for coal-fired power plant using a modular concept based on CFB technology. 2 photos.

  15. Axial gas transport and loss of pressure after ballooning rupture of high burn-up fuel rods subjected to LOCA conditions

    International Nuclear Information System (INIS)

    Wiesenack, Wolfgang; Oberlaender, Barbara; Kekkonen, Laura

    2008-01-01

    The OECD Halden Reactor Project has implemented integral in-pile tests on issues related to fuel behaviour under LOCA conditions. In this test series, the interaction of bonded fuel and cladding, the behaviour of fragmented fuel around the ballooning area, and the axial gas communication in high burn-up rods as affected by gap closure and fuel-clad bonding are of major interest for the investigations. In the Halden reactor tests, the decay heat is simulated by a low level of nuclear heating, in contrast to the heating conditions implemented in hot laboratory set-ups, and the thermal expansion of fuel and cladding relative to each other is more similar to the real event. The paper deals with observations regarding the loss of rod pressure following the rupture of the cladding. In the majority of the tests conducted so far, the rod pressure dropped practically instantaneously as a consequence of ballooning rupture, while one test showed a remarkably slow pressure loss. The slow loss of pressure in this test was analysed, showing that the 'hydraulic diameter' of the rod over an un-distended upper part was about 30 - 35 μm which is typical of high burn-up fuel at hot-standby conditions. The 'plug' of fuel restricts the gas flow from the plenum through the fuel column and thus limits the availability of high pressure gas for driving the ballooning. This observation is relevant for the analysis of the behaviour of a full length fuel rod under LOCA conditions since restricted gas flow may influence bundle blockage and the number of failures. (authors)

  16. Laminar burning velocity and Markstein length of nitrogen diluted natural gas/hydrogen/air mixtures at normal, reduced and elevated pressures

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Haiyan [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Eng., Xi' an Jiaotong University (China); Institute of High Performance Computing, A-star (Singapore); Ji, Min; Jiao, Qi; Huang, Qian; Huang, Zuohua [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Eng., Xi' an Jiaotong University (China)

    2009-04-15

    Flame propagation of premixed nitrogen diluted natural gas/hydrogen/air mixtures was studied in a constant volume combustion bomb under various initial pressures. Laminar burning velocities and Markstein lengths were obtained for the diluted stoichiometric fuel/air mixtures with different hydrogen fractions and diluent ratios under various initial pressures. The results showed that both unstretched flame speed and unstretched burning velocity are reduced with the increase in initial pressure (except when the hydrogen fraction is 80%) as well as diluent ratio. The velocity reduction rate due to diluent addition is determined mainly by hydrogen fraction and diluent ratio, and the effect of initial pressure is negligible. Flame stability was studied by analyzing Markstein length. It was found that the increase of initial pressure and hydrogen fraction decreases flame stability and the flame tends to be more stable with the addition of diluent gas. Generally speaking, Markstein length of a fuel with low hydrogen fraction is more sensitive to the change of initial pressure than that of a one with high hydrogen fraction. (author)

  17. Trace gas and particle emissions from domestic and industrial biofuel use and garbage burning in central Mexico

    Science.gov (United States)

    Christian, T. J.; Yokelson, R. J.; Cárdenas, B.; Molina, L. T.; Engling, G.; Hsu, S.-C.

    2010-01-01

    In central Mexico during the spring of 2007 we measured the initial emissions of 12 gases and the aerosol speciation for elemental and organic carbon (EC, OC), anhydrosugars, Cl-, NO3-, and 20 metals from 10 cooking fires, four garbage fires, three brick making kilns, three charcoal making kilns, and two crop residue fires. Global biofuel use has been estimated at over 2600 Tg/y. With several simple case studies we show that cooking fires can be a major, or the major, source of several gases and fine particles in developing countries. Insulated cook stoves with chimneys were earlier shown to reduce indoor air pollution and the fuel use per cooking task. We confirm that they also reduce the emissions of VOC pollutants per mass of fuel burned by about half. We did not detect HCN emissions from cooking fires in Mexico or Africa. Thus, if regional source attribution is based on HCN emissions typical for other types of biomass burning (BB), then biofuel use and total BB will be underestimated in much of the developing world. This is also significant because cooking fires are not detected from space. We estimate that ~2000 Tg/y of garbage are generated globally and about half may be burned, making this a commonly overlooked major global source of emissions. We estimate a fine particle emission factor (EFPM2.5) for garbage burning of ~10.5±8.8 g/kg, which is in reasonable agreement with very limited previous work. We observe large HCl emission factors in the range 2-10 g/kg. Consideration of the Cl content of the global waste stream suggests that garbage burning may generate as much as 6-9 Tg/yr of HCl, which would make it a major source of this compound. HCl generated by garbage burning in dry environments may have a relatively greater atmospheric impact than HCl generated in humid areas. Garbage burning PM2.5 was found to contain levoglucosan and K in concentrations similar to those for biomass burning, so it could be a source of interference in some areas when using

  18. Trace gas and particle emissions from domestic and industrial biofuel use and garbage burning in central Mexico

    Directory of Open Access Journals (Sweden)

    T. J. Christian

    2010-01-01

    Full Text Available In central Mexico during the spring of 2007 we measured the initial emissions of 12 gases and the aerosol speciation for elemental and organic carbon (EC, OC, anhydrosugars, Cl, NO3, and 20 metals from 10 cooking fires, four garbage fires, three brick making kilns, three charcoal making kilns, and two crop residue fires. Global biofuel use has been estimated at over 2600 Tg/y. With several simple case studies we show that cooking fires can be a major, or the major, source of several gases and fine particles in developing countries. Insulated cook stoves with chimneys were earlier shown to reduce indoor air pollution and the fuel use per cooking task. We confirm that they also reduce the emissions of VOC pollutants per mass of fuel burned by about half. We did not detect HCN emissions from cooking fires in Mexico or Africa. Thus, if regional source attribution is based on HCN emissions typical for other types of biomass burning (BB, then biofuel use and total BB will be underestimated in much of the developing world. This is also significant because cooking fires are not detected from space. We estimate that ~2000 Tg/y of garbage are generated globally and about half may be burned, making this a commonly overlooked major global source of emissions. We estimate a fine particle emission factor (EFPM2.5 for garbage burning of ~10.5±8.8 g/kg, which is in reasonable agreement with very limited previous work. We observe large HCl emission factors in the range 2–10 g/kg. Consideration of the Cl content of the global waste stream suggests that garbage burning may generate as much as 6–9 Tg/yr of HCl, which would make it a major source of this compound. HCl generated by garbage burning in dry environments may have a relatively greater atmospheric impact than HCl generated in humid areas. Garbage burning PM2.5 was found to contain levoglucosan and K in concentrations similar to those for

  19. The lean service machine.

    Science.gov (United States)

    Swank, Cynthia Karen

    2003-10-01

    Jefferson Pilot Financial, a life insurance and annuities firm, like many U.S. service companies at the end of the 1990s was looking for new ways to grow. Its top managers recognized that JPF needed to differentiate itself in the eyes of its customers, the independent life-insurance advisers who sell and service policies. To establish itself as these advisers' preferred partner, it set out to reduce the turnaround time on policy applications, simplify the submission process, and reduce errors. JPF's managers looked to the "lean production" practices that U.S. manufacturers adopted in response to competition from Japanese companies. Lean production is built around the concept of continuous-flow processing--a departure from traditional production systems, in which large batches are processed at each step. JPF appointed a "lean team" to reengineer its New Business unit's operations, beginning with the creation of a "model cell"--a fully functioning microcosm of JPF's entire process. This approach allowed managers to experiment and smooth out the kinks while working toward an optimal design. The team applied lean-manufacturing practices, including placing linked processes near one another, balancing employees' workloads, posting performance results, and measuring performance and productivity from the customer's perspective. Customer-focused metrics helped erode the employees' "My work is all that matters" mind-set. The results were so impressive that JPF is rolling out similar systems across many of its operations. To convince employees of the value of lean production, the lean team introduced a simulation in which teams compete to build the best paper airplane based on invented customer specifications. This game drives home lean production's basic principles, establishing a foundation for deep and far-reaching changes in the production system.

  20. Lean hydrous and anhydrous bioethanol combustion in spark ignition engine at idle

    International Nuclear Information System (INIS)

    Chuepeng, Sathaporn; Srisuwan, Sudecha; Tongroon, Manida

    2016-01-01

    Highlights: • Anhydrous ethanol burns fastest in uncalibrated engine at equal equivalence ratio. • The leaner hydrous ethanol combustion tends to elevate the COV in imep. • Hydrous ethanol consumption was 10% greater than anhydrous ethanol at ϕ = 0.67 limit. • Optimizing alternative fuel engine at idle for stability and emission is suggested. - Abstract: The applications of anhydrous bioethanol to substitute or replace gasoline fuel have shown to attain benefits in terms of engine thermal efficiency, power output and exhaust emissions from spark ignition engines. A hydrous bioethanol has also been gained more attention due to its energy and cost effectiveness. The main aim of this work is to minimize fuel quantity injected to the intake ports of a four-cylinder engine under idle condition. The engine running with hydrous ethanol undergoes within lean-burn condition as its combustion stability is analyzed using an engine indicating system. Coefficient of variation in indicated mean effective pressure is an indicator for combustion stability with hydrocarbon and carbon monoxide emission monitoring as a supplement. Anhydrous ethanol burns faster than hydrous ethanol and gasoline in the uncalibrated engine at the same fuel-to-air equivalence ratio under idle condition. The leaner hydrous ethanol combustion tends to elevate the coefficient of variation in indicated mean effective pressure. The experimental results have found that the engine consumes greater hydrous ethanol by 10% on mass basis compared with those of anhydrous ethanol at the lean limit of fuel-to-air equivalence ratio of 0.67. The results of exhaust gas analysis were compared with those predicted by chemical equilibrium analysis of the fuel-air combustion; the resemble trends were found. Calibrating the alternative fueled engine for fuel injection quantity should be accomplished at idle with combustion stability and emissions optimization.

  1. EPA Lean Government Initiative: How to Replicate Lean Successes

    Science.gov (United States)

    This Lean Replication Primer describes how EPA Offices and Regions can identify and adapt successful practices from previous Lean projects to “replicate” their successes and generate further improvements.

  2. Can lean save lives?

    Science.gov (United States)

    Fillingham, David

    2007-01-01

    The purpose of this paper is to show how over the last 18 months Bolton Hospitals NHS Trust have been exploring whether or not lean methodologies, often known as the Toyota Production System, can indeed be applied to healthcare. This paper is a viewpoint. One's early experience is that lean really can save lives. The Toyota Production System is an amazingly successful way of manufacturing cars. It cannot be simply translated unthinkingly into a hospital but lessons can be learned from it and the method can be adapted and developed so that it becomes owned by healthcare staff and focused towards the goal of improved patient care. Working in healthcare is a stressful and difficult thing. Everyone needs a touch of inspiration and encouragement. Applying lean to healthcare in Bolton seems to be achieving just that for those who work there.

  3. Rethinking Lean Service

    Science.gov (United States)

    Seddon, John; O'Donovan, Brendan; Zokaei, Keivan

    Ever since Levitt's influential Harvard Business Review article 'Production-Line Approach to Service' was published in 1972, it has been common for services to be treated like production lines in both the academic literature and more widely in management practice. The belief that achieving economies of scale will reduce unit costs is a common feature of management decision-making. As technological advancement has produced ever more sophisticated IT and telephony, it has become increasingly easier for firms to standardise and off-shore services. The development of the 'lean' literature has only helped to emphasise the same underlying management assumptions: by managing cost and workers' activity, organisational performance is expected to improve. This chapter argues that through misinterpretation of the core paradigm 'lean' has become subsumed into the 'business as usual' of conventional service management. As a result, 'lean' has become synonymous with 'process efficiency' and the opportunity for significant performance improvement - as exemplified by Toyota - has been missed.

  4. Characterization of biomass producer gas as fuel for stationary gas engines in combined heat and power production

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper

    2008-01-01

    The aim of this project has been the characterization of biomass producer gas as a fuel for stationary gas engines in heat and power production. More than 3200 hours of gas engine operation, with producer gas as fuel, has been conducted at the biomass gasification combined heat and power (CHP...... different measuring methods. Likewise, no particles were detected in the gas. Considerable amounts of NH3 were measured in the produced gas.An analysis of engine operation at varying load has been carried out. Standard emissions, load and efficiency have been measured at varying operating conditions ranging...... from 50% to 90% load. Biomass producer gas is an excellent lean burn engine fuel: Operation of a natural aspirated engine has been achieved for 1.2...

  5. Rayleigh/Raman/LIF measurements in a turbulent lean premixed combustor

    Energy Technology Data Exchange (ETDEWEB)

    Nandula, S.P.; Pitz, R.W. [Vanderbilt Univ., Nashville, TN (United States); Barlow, R.S. [Sandia National Labs., Livermore, CA (United States)] [and others

    1995-10-01

    Much of the industrial electrical generation capability being added worldwide is gas-turbine engine based and is fueled by natural gas. These gas-turbine engines use lean premixed (LP) combustion to meet the strict NO{sub x} emission standards, while maintaining acceptable levels of CO. In conventional, diffusion flame gas turbine combustors, large amount of NO{sub x} forms in the hot stoichiometric zones via the Zeldovich (thermal) mechanism. Hence, lean premixed combustors are rapidly becoming the norm, since they are specifically designed to avoid these hot stoichiometric zones and the associated thermal NO, However, considerable research and development are still required to reduce the NO{sub x} levels (25-40 ppmvd adjusted to 15% O{sub 2} with the current technology), to the projected goal of under 10 ppmvd by the turn of the century. Achieving this objective would require extensive experiments in LP natural gas (or CH{sub 4}) flames for understanding the combustion phenomena underlying the formation of the exhaust pollutants. Although LP combustion is an effective way to control NO{sub x}, the downside is that it increases the CO emissions. The formation and destruction of the pollutants (NO{sub x} and CO) are strongly affected by the fluid mechanics, the finite-rate chemistry, and their (turbulence-chemistry) interactions. Hence, a thorough understanding of these interactions is vital for controlling and reducing the pollutant emissions. The present research is contributing to this goal by providing a detailed nonintrusive laser based data set with good spatial and temporal resolutions of the pollutants (NO and CO) along with the major species, temperature, and OH. The measurements reported in this work, along with the existing velocity data on a turbulent LP combustor burning CH{sub 4}, would provide insight into the turbulence-chemistry interactions and their effect on pollutant formation.

  6. Burn Wise

    Science.gov (United States)

    Burn Wise is a partnership program of the U.S. Environmental Protection Agency that emphasizes the importance of burning the right wood, the right way, in the right appliance to protect your home, health, and the air we breathe.

  7. Lean Management Genesis

    Directory of Open Access Journals (Sweden)

    Parkes Aneta

    2015-12-01

    Full Text Available Lean Management is a philosophy and management concept, based on reduction of the waste and resources used in the process of producing goods and providing services. Lean Management genesis dates back to scientific management in America (for example concepts of H. Ford and F.W. Taylor and quality management, including development of TQM concept. Japanese Toyota Production System has been inspired by chosen elements of these concepts, and then it evolved towards global concept called Toyota Way (which connects production rules with values and work attitude.

  8. Improving Healthcare through Lean Management

    DEFF Research Database (Denmark)

    Nielsen, Anders Paarup; Edwards, Kasper

    2011-01-01

    The ideas and principles from lean management are now widely being adopted within the healthcare sector. The analysis in this paper shows that organizations within healthcare most often only implement a limited set of tools and methods from the lean tool-box. Departing from a theoretical analysis...... of the well-known and universal lean management principles in the context of the healthcare this paper will attempt to formulate and test four hypotheses about possible barriers to the successful implementation of lean management in healthcare. The first hypothesis states that lean management in healthcare....... The paper concludes by discussing the implications of hypothesis two, three, and four for the successful application of lean management within healthcare. Is it concluded that this requires a transformative and contingent approach to lean management where the universal principles of the lean philosophy...

  9. Lean in Air Permitting Guide

    Science.gov (United States)

    The Lean in Air Permitting Guide is designed to help air program managers at public agencies better understand the potential value and results that can be achieved by applying Lean improvement methods to air permitting processes.

  10. The Lean and Environment Toolkit

    Science.gov (United States)

    This Lean and Environment Toolkit assembles practical experience collected by the U.S. Environmental Protection Agency (EPA) and partner companies and organizations that have experience with coordinating Lean implementation and environmental management.

  11. Techniques for enhancing durability and equivalence ratio control in a rich-lean, three-stage ground power gas turbine combustor

    Science.gov (United States)

    Schultz, D. F.

    1982-01-01

    Rig tests of a can-type combustor were performed to demonstrate two advanced ground power engine combustor concepts: steam cooled rich-burn combustor primary zones for enhanced durability; and variable combustor geometry for three stage combustion equivalence ratio control. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This offers the potential of both long life and reduced use of strategic materials for liner fabrication. Three degrees of variable geometry were successfully implemented to control airflow distribution within the combustor. One was a variable blade angle axial flow air swirler to control primary airflow while the other two consisted of rotating bands to control secondary and tertiary or dilution air flow.

  12. Ghrelin receptor controls obesity by fat burning

    Science.gov (United States)

    Emerging evidence show that brown fat in the body produces heat to burn energy, thus prompting weight loss. Ghrelin is the only known hormone which increases appetite and promotes weight gain. We have reported that mice that lack the receptor which mediates the functions of ghrelin are lean. Our fu...

  13. Lean leadership: an ethnographic study

    NARCIS (Netherlands)

    Aij, K.H.; Visse, M.A.; Widdershoven, G.A.M.

    2015-01-01

    Purpose – The purpose of this study is to provide a critical analysis of contemporary Lean leadership in the context of a healthcare practice. The Lean leadership model supports professionals with a leading rolein implementing Lean.This article presents a case study focusing specifcally on

  14. Lean With a Human Face

    DEFF Research Database (Denmark)

    Hasle, Peter; Jensen, Per Langaa

    2008-01-01

    The consequences for quality of work of lean manufacturing is discussed in the international litterature, and several authors suggest increased work speed, stress, and muscoskeletal diseases as a consequence of lean. The Danish experience with lean has been studied through interviews with managers...

  15. Environmental and energy efficiency evaluation of residential gas and heat pump heating

    International Nuclear Information System (INIS)

    Ganji, A.R.

    1993-01-01

    Energy efficiency and source air pollutant emission factors of gas heaters, gas engine heat pumps, and electric heat pumps for domestic heating have been evaluated and compared. The analysis shows that with the present state of technology, gas engine heat pumps have the highest energy efficiency followed by electric heat pumps and then gas heaters. Electric heat pumps produce more than twice as much NO x , and comparable CO 2 and CO per unit of useful heating energy compared to natural gas heaters. CO production per unit of useful heating energy from gas engine heat pumps without any emission control is substantially higher than electric heat pumps and natural gas heaters. NO x production per unit of useful heating energy from natural gas engine heat pumps (using lean burn technology) without any emission control is about the same as effective NO x production from electric heat pumps. Gas engine heat pumps produce about one-half CO 2 compared to electric heat pumps

  16. Design thinking & lean

    DEFF Research Database (Denmark)

    Bravos, Cynthia; Adler, Isabel K.

    2015-01-01

    This paper aims at presenting how a Brazilian innovation consultancy guided a collaborative development of a mobile solution using the Design Thinking approach (Vianna et al, 2012) and Lean principles (Ries, 2011). It will describe tools and methods used and how it was applied to requirement gath...

  17. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter Emitted from Burning Kerosene, Liquid Petroleum Gas, and Wood Fuels in Household Cookstoves

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10%...

  18. IFPE/IFA-597.3, centre-line temperature, fission gas release and clad elongation at high burn-up (60-62 MWd/kg)

    International Nuclear Information System (INIS)

    Turnbull, J.A.

    2003-01-01

    Description: The fuel segments for the high burn-up integral rod behaviour test IFA-597 were taken from fuel rod 33-25065, which was irradiated in the Ringhals 1 BWR for approximately 12 years. The irradiation of this rod and its sibling rod 33-25046 was performed in two stages. During the first irradiation, 1980 to 1986, the rods were part of Ringhals assembly 6477 and an approximate rod averaged burn-up of 31 MWd/kg UO 2 was reached. The rods were then placed into fuel assembly 9902 for a second period of irradiation from 1986 to 1992. The location of the fuel rods 33-25065 and 33-25046 in this assembly were in positions 9902/D and 9902/E4 respectively. A final rod averaged burn-up of 52 MWd/kg UO 2 was achieved. The burn-up at the location of the Halden segments was estimated as 59 MWd/kg UO 2 , well beyond the formation of High Burn-up Structure (Hobs) formation at the pellet rim. At the rim, the burn-up was estimated as 130 MWd/kg UO 2 . After commercial irradiation, PIE was performed at Studsvik. Inner and outer clad oxide thickness measurements were 42 and 5 microns respectively. The measured cold rod diameter varied between 12.20 and 12.25 mm, thus only a small amount of creep-down had occurred from the original diameter of 12.25 mm. Cold gap measurements were taken by diametral compression of the clad onto the fuel. The stiffness changes twice during these measurements, the first (relocated gap) associated with the onset of pellet fragment movement, the second (compressed gap) when the fragments are together and the pellet is compressed. For these rods, the compressed diametral gap was measured as 30 microns. This is in agreement with the pellet and cladding being in contact during the final irradiation cycle, i.e., at ∼12 kW/m. FGR measurements were made after puncturing and values of 2.5%-3.3% were calculated from the extracted gas. The uncertainty is due to different methods of calculation. Ceramography showed a normal crack pattern and no evidence of

  19. A Comparison of Three Second-generation Swirl-Venturi Lean Direct Injection Combustor Concepts

    Science.gov (United States)

    Tacina, Kathleen M.; Podboy, Derek P.; He, Zhuohui Joe; Lee, Phil; Dam, Bidhan; Mongia, Hukam

    2016-01-01

    Three variations of a low emissions aircraft gas turbine engine combustion concept were developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. All three variations were based on the baseline 9- point SV-LDI configuration reported previously. The three second generation SV-LDI variations are called the 5-recess configuration, the flat dome configuration, and the 9- recess configuration. These three configurations were tested in a NASA Glenn Research Center medium pressure flametube. All three second generation variations had better low power operability than the baseline 9-point configuration. All three configurations had low NO(sub x) emissions, with the 5-recess configuration generally having slightly lower NO(x) than the flat dome or 9-recess configurations. Due to the limitations of the flametube that prevented testing at pressures above 20 atm, correlation equations were developed for the at dome and 9-recess configurations so that the landing-takeoff NO(sub x) emissions could be estimated. The flat dome and 9-recess landing-takeoff NO(x) emissions are estimated to be 81-88% below the CAEP/6 standards, exceeding the project goal of 75% reduction.

  20. A Second Generation Swirl-Venturi Lean Direct Injection Combustion Concept

    Science.gov (United States)

    Tacina, Kathleen M.; Chang, Clarence T.; He, Zhuohui Joe; Lee, Phil; Dam, Bidhan; Mongia, Hukam

    2014-01-01

    A low-NO (sub x) aircraft gas turbine engine combustion concept was developed and tested. The concept is a second generation swirl-venturi lean direct injection (SV-LDI) concept. LDI is a lean-burn combustion concept in which the fuel is injected directly into the flame zone. Three second generation SV-LDI configurations were developed. All three were based on the baseline 9-point SV-LDI configuration reported previously. These second generation configurations had better low power operability than the baseline 9-point configuration. Two of these second generation configurations were tested in a NASA Glenn Research Center flametube; these two configurations are called the at dome and 5-recess configurations. Results show that the 5-recess configuration generally had lower NO (sub x) emissions than the flat dome configuration. Correlation equations were developed for the flat dome configuration so that the landing-takeoff NO (sub x) emissions could be estimated. The flat dome landing-takeoff NO (sub x) is estimated to be 87-88 percent below the CAEP/6 standards, exceeding the ERA project goal of 75 percent reduction.

  1. Lean mixture engine testing and evaluation program. [for automobile engine pollution and fuel performances

    Science.gov (United States)

    Dowdy, M. W.; Hoehn, F. W.; Griffin, D. C.

    1975-01-01

    Experimental results for fuel consumption and emissions are presented for a 350 CID (5.7 liter) Chevrolet V-8 engine modified for lean operation with gasoline. The lean burn engine achieved peak thermal efficiency at an equivalence ratio of 0.75 and a spark advance of 60 deg BTDC. At this condition the lean burn engine demonstrated a 10% reduction in brake specific fuel consumption compared with the stock engine; however, NOx and hydrocarbon emissions were higher. With the use of spark retard and/or slightly lower equivalence ratios, the NOx emissions performance of the stock engine was matched while showing a 6% reduction in brake specific fuel consumption. Hydrocarbon emissions exceeded the stock values in all cases. Diagnostic data indicate that lean performance in the engine configuration tested is limited by ignition delay, cycle-to-cycle pressure variations, and cylinder-to-cylinder distribution.

  2. Lean start-up

    DEFF Research Database (Denmark)

    Rasmussen, Erik Stavnsager; Tanev, Stoyan

    2016-01-01

    The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The ma...... and the final business model. In other words: The start-up must first nail the problem together with the customers, then develop the solution and test, and then in the end scale it to a full-grown business model.......The risk of launching new products and starting new firms is known to be extremely high. The Lean Start-up approach is a way of reducing these risks and enhancing the chances for success by validating the products and services in the market with customers before launching it in full scale. The main...

  3. Green and lean management

    CERN Document Server

    Davim, J

    2017-01-01

    This book focusses on the challenges and changes organizational management faces in an era when the need to develop environmentally aware processes meets high levels of competition. It covers the synergetic effects, how re-use, recycling, waste reduction, and other sustainable production strategies can add value, low costs and time of production. Sustainable business behavior is not only an environmental perspective on management, but more and more contains an organizational perspective. Taking into account these issues, green and lean management appears as the way managers can drive their employees to continuously improve the management processes that add value to the organization and costumers. This book provides information on principles, strategies, models, and applications of green and lean management, and at the same time communicates the latest research activity relating to this scientific field world-wide.

  4. Lean Leadership - Organizational Buy - Ins

    Directory of Open Access Journals (Sweden)

    Dr. Revathi Iyer

    2017-05-01

    Full Text Available Great organizations have become leaders due to their leadership and sustainable initiatives. One such initiative is adoption of lean leadership to align core strategies with all functional areas of business. Leadership is likely to take place in a lean environment because improvements that happen are continual and can only be supported by leadership which understands this important aspect. The topic of lean leadership organizational buy ins speaks on how lean leadership could affect organizations that adopt lean and other quality tools. Purpose of the study This study has been undertaken to understand When leadership more of is likely to take place in lean . Leadership plays a very important role while adopting lean processes and how lean leadership can address the process problem. Application of leadership lenses to lean processes needs great foresight thought and creativity. It has been also observed that lean management and lean processes can happen only if leadership is able to effectively communicate the thought of continual improvement to bring in a lean organization and a future state of processes where everything of a firm process and procedure is continually improving and the best strategies to manage this change becomes a philosophy. Lean leadership is associated with such a change. This enables leadership vision to be clear as it paves the way for current state and is clear to everyone. It is this leadership vision which enables employees to think and act in a way that perpetrates continual improvement. Hence leadership buys ins for lean are very necessary. The purpose of the study is also to understand how leaders can not only use cost reduction but also reducing time-to-market improving service quality and reducing risk exposure by adopting lean methods . it has been also seen that there is overall productivity and efficiency in organizations holistically when leadership endorses lean methodology. Radnor Z. and Bucci G. 2007

  5. NOx emission control for gas turbines: A 1991 update on regulations and technology (Part II)

    International Nuclear Information System (INIS)

    Schorr, M.M.

    1991-01-01

    The technologies that are available for the control of NO x emissions from gas turbines utilize the factors that impact the formation of NO x described in the previous section and include (1) diluent injection (i.e., water or steam) into the combustion zone, which is a front-end control technology that lowers the combustor flame temperature, (2) selective catalytic reduction (SCR), which is a back-end exhaust gas cleanup system, (3) dry low NO x combustors (DLN), which use staged combustion and very lean fuel-air mixtures (they are currently being introduced), and (4) catalytic combustion systems that hold the promise of achieving extremely low emission levels without resorting to exhaust gas cleanup. This last option is being developed to burn very lean fuel-air mixtures, but will require significant technological breakthroughs; it is still several years away from becoming commercially available

  6. Lean leadership: an ethnographic study.

    Science.gov (United States)

    Aij, Kjeld Harald; Visse, Merel; Widdershoven, Guy A M

    2015-01-01

    The purpose of this study is to provide a critical analysis of contemporary Lean leadership in the context of a healthcare practice. The Lean leadership model supports professionals with a leading role in implementing Lean. This article presents a case study focusing specifically on leadership behaviours and issues that were experienced, observed and reported in a Dutch university medical centre. This ethnographic case study provides auto-ethnographic accounts based on experiences, participant observation, interviews and document analysis. Characteristics of Lean leadership were identified to establish an understanding of how to achieve successful Lean transformation. This study emphasizes the importance for Lean leaders to go to the gemba, to see the situation for one's own self, empower health-care employees and be modest. All of these are critical attributes in defining the Lean leadership mindset. In this case study, Lean leadership is specifically related to healthcare, but certain common leadership characteristics are relevant across all fields. This article shows the value of an auto-ethnographic view on management learning for the analysis of Lean leadership. The knowledge acquired through this research is based on the first author's experiences in fulfilling his role as a health-care leader. This may help the reader examining his/her own role and reflecting on what matters most in the field of Lean leadership.

  7. Pollutant Formation during the Occurrence of Flame Instabilities under Very-Lean Combustion Conditions in a Liquid-Fuel Burner

    Directory of Open Access Journals (Sweden)

    Maria Grazia De Giorgi

    2017-03-01

    Full Text Available Recent advances in gas turbine combustor design are aimed at achieving low exhaust emissions, hence modern aircraft jet engines are designed with lean-burn combustion systems. In the present work, we report an experimental study on lean combustion in a liquid fuel burner, operated under a non-premixed (single point injection regime that mimics the combustion in a modern aircraft engine. The flame behavior was investigated in proximity of the blow-out limit by an intensified high rate Charge-Coupled Device (CCD camera equipped with different optical filters to selectively record single species chemiluminescence emissions (e.g., OH*, CH*. Analogous filters were also used in combination with photomultiplier (PMT tubes. Furthermore this work investigates well-mixed lean low NOx combustion where mixing is good and generation of solid carbon particulate emissions should be very low. An analysis of pollutants such as fine particles and gaseous emissions was also performed. Particle number concentrations and size distributions were measured at the exhaust of the combustion chamber by two different particle size measuring instruments: a scanning mobility particle sizer (SMPS and an Electrical Low Pressure Impactor (ELPI. NOx concentration measurements were performed by using a cross-flow modulation chemiluminescence detection system; CO concentration emissions were acquired with a Cross-flow modulation Non-dispersive infrared (NDIR absorption method. All the measurements were completed by diagnostics of the fundamental combustor parameters. The results herein presented show that at very-lean conditions the emissions of both particulate matter and CO was found to increase most likely due to the occurrence of flame instabilities while the NOx were observed to reduce.

  8. Numerical simulation of nitrogen oxide formation in lean premixed turbulent H2/O2/N2 flames

    DEFF Research Database (Denmark)

    Day, Marc S.; Bell, John B.; Gao, Xinfeng

    2011-01-01

    Lean premixed hydrogen flames are thermodiffusively unstable and burn in cellular structures. Within these cellular structures the flame is locally enriched by preferential diffusion of hydrogen, leading to local hotspots that burn more intensely than an idealized flat steady flame at comparable ...

  9. Organizational change through Lean Thinking.

    Science.gov (United States)

    Tsasis, Peter; Bruce-Barrett, Cindy

    2008-08-01

    In production and manufacturing plants, Lean Thinking has been used to improve processes by eliminating waste and thus enhancing efficiency. In health care, Lean Thinking has emerged as a comprehensive approach towards improving processes embedded in the diagnostic, treatment and care activities of health-care organizations with cost containment results. This paper provides a case study example where Lean Thinking is not only used to improve efficiency and cost containment, but also as an approach to effective organizational change.

  10. Applying lean thinking in construction

    Directory of Open Access Journals (Sweden)

    Remon Fayek Aziz

    2013-12-01

    Full Text Available The productivity of the construction industry worldwide has been declining over the past 40 years. One approach for improving the situation is using lean construction. Lean construction results from the application of a new form of production management to construction. Essential features of lean construction include a clear set of objectives for the delivery process, aimed at maximizing performance for the customer at the project level, concurrent design, construction, and the application of project control throughout the life cycle of the project from design to delivery. An increasing number of construction academics and professionals have been storming the ramparts of conventional construction management in an effort to deliver better value to owners while making real profits. As a result, lean-based tools have emerged and have been successfully applied to simple and complex construction projects. In general, lean construction projects are easier to manage, safer, completed sooner, and cost less and are of better quality. Significant research remains to complete the translation to construction of lean thinking in Egypt. This research will discuss principles, methods, and implementation phases of lean construction showing the waste in construction and how it could be minimized. The Last Planner System technique, which is an important application of the lean construction concepts and methodologies and is more prevalent, proved that it could enhance the construction management practices in various aspects. Also, it is intended to develop methodology for process evaluation and define areas for improvement based on lean approach principles.

  11. Lean software development in action

    CERN Document Server

    Janes, Andrea

    2014-01-01

    This book illustrates how goal-oriented, automated measurement can be used to create Lean organizations and to facilitate the development of Lean software, while also demonstrating the practical implementation of Lean software development by combining tried and trusted tools. In order to be successful, a Lean orientation of software development has to go hand in hand with a company's overall business strategy. To achieve this, two interrelated aspects require special attention: measurement and experience management. In this book, Janes and Succi provide the necessary knowledge to establish "

  12. Prediction of soot and thermal radiation in a model gas turbine combustor burning kerosene fuel spray at different swirl levels

    Science.gov (United States)

    Ghose, Prakash; Patra, Jitendra; Datta, Amitava; Mukhopadhyay, Achintya

    2016-05-01

    Combustion of kerosene fuel spray has been numerically simulated in a laboratory scale combustor geometry to predict soot and the effects of thermal radiation at different swirl levels of primary air flow. The two-phase motion in the combustor is simulated using an Eulerian-Lagragian formulation considering the stochastic separated flow model. The Favre-averaged governing equations are solved for the gas phase with the turbulent quantities simulated by realisable k-ɛ model. The injection of the fuel is considered through a pressure swirl atomiser and the combustion is simulated by a laminar flamelet model with detailed kinetics of kerosene combustion. Soot formation in the flame is predicted using an empirical model with the model parameters adjusted for kerosene fuel. Contributions of gas phase and soot towards thermal radiation have been considered to predict the incident heat flux on the combustor wall and fuel injector. Swirl in the primary flow significantly influences the flow and flame structures in the combustor. The stronger recirculation at high swirl draws more air into the flame region, reduces the flame length and peak flame temperature and also brings the soot laden zone closer to the inlet plane. As a result, the radiative heat flux on the peripheral wall decreases at high swirl and also shifts closer to the inlet plane. However, increased swirl increases the combustor wall temperature due to radial spreading of the flame. The high incident radiative heat flux and the high surface temperature make the fuel injector a critical item in the combustor. The injector peak temperature increases with the increase in swirl flow mainly because the flame is located closer to the inlet plane. On the other hand, a more uniform temperature distribution in the exhaust gas can be attained at the combustor exit at high swirl condition.

  13. Analysis of UO2 fuel structure for low and high burn-up and its impact on fission gas release

    International Nuclear Information System (INIS)

    Szuta, M.; El-Koliel, M.S.

    1999-01-01

    During irradiation, uranium dioxide (UO 2 ) fuel undergo important restructuring mainly represented by densification and swelling, void migration, equiaxed grain growth, grain subdivision, and the formation of columnar grains. The purpose of this study is to obtain a comprehensive picture of the phenomenon of equiaxed grain growth in UO 2 ceramic material. The change of the grain size in high-density uranium dioxide as a function of temperature, initial grain size, time, and burnup is calculated. Algorithm of fission gas release from UO 2 fuel during high temperature irradiation at high burnup taking into account grain growth effect is presented. Theoretical results are compared with experimental data. (author)

  14. First Lean, then modularisation

    DEFF Research Database (Denmark)

    Petersen, Kristian R.; Madsen, Erik Skov; Bilberg, Arne

    2016-01-01

    of Europe’s leading offshore wind power operators with more than 1,000 wind turbine generators in operation. By focusing on this company, in-depth insights into its operations and maintenance processes are investigated. Findings – Lean is identified to constitute an important first step before...... and resources can take place. The authors also establish a foundation for the development of a software tool to support the development of the modularisation of maintenance tasks. Originality/value – The present study contributes to the rather immature field of research on the operations and maintenance...

  15. Gas turbine topping combustor

    Science.gov (United States)

    Beer, J.; Dowdy, T.E.; Bachovchin, D.M.

    1997-06-10

    A combustor is described for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone. 14 figs.

  16. Lean approach in knowledge work

    Directory of Open Access Journals (Sweden)

    Hanna Kropsu-Vehkapera

    2018-05-01

    Full Text Available Purpose: Knowledge work productivity is a key area of improvement for many organisations. Lean approach is a sustainable way to achieve operational excellence and can be applied in many areas. The purpose of this novel study is to examine the potential of using lean approach for improving knowledge work practices. Design/methodology/approach: A systematic literature review has been carried out to study how lean approach is realised in knowledge work. The research is conceptual in nature and draws upon earlier research findings. Findings: This study shows that lean studies’ in knowledge work is an emerging research area. This study documents the methods and practices implemented in knowledge work to date, and presents a knowledge work continuum, which is an essential framework for effective lean approach deployment and to frame future research focus in knowledge work productivity. Research limitations/implications: This study structures the concept of knowledge work and outlines a concrete concept derived from earlier literature. The study summarises the literature on lean in knowledge work and highlights, which methods are used. More research is needed to understand how lean can be implemented in complex knowledge work environment and not only on the repetitive knowledge work. The limitations of this research are due to the limited availability of previous research. Practical implications: To analyse the nature of knowledge work, we implicate the areas where lean methods especially apply to improving knowledge work productivity. When applying lean in knowledge work context the focus should be using the people better and improving information flow. Originality/value: This study focuses on adapting lean methods into a knowledge work context and summarises earlier research done in this field. The study discusses the potential to improve knowledge work productivity by implementing lean methods and presents a unique knowledge work continuum to

  17. EDUCATION FOR LEAN & LEAN FOR EDUCATION: A LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    Saveta Vukadinovic

    2017-03-01

    Full Text Available The purpose of this paper is to investigate and understand how tools and principles of Lean philosophy can be adopted to improve the effectiveness of engineering education by providing services beyond the competition and costs below the competition, and how engineering education can provide better prepared engineering professionals capable to work in dynamic Lean environments by developing multidisciplinary knowledge and skills. Paper will be based on analysis of relevant scientific and professional literature sources, including certain elements of description, classification, explanation and prediction. The authors will use detailed literature review to explain complex relationship and interdependence between Lean philosophy and engineering education and answer the question what benefits modern Lean enterprises may expect from properly educated and qualified engineers and how application of Lean tools and principles can improve the system of engineering education.

  18. Ares Launch Vehicles Lean Practices Case Study

    Science.gov (United States)

    Doreswamy, Rajiv, N.; Self, Timothy A.

    2008-01-01

    This viewgraph presentation describes test strategies and lean philisophies and practices that are applied to Ares Launch Vehicles. The topics include: 1) Testing strategy; 2) Lean Practices in Ares I-X; 3) Lean Practices Applied to Ares I-X Schedule; 4) Lean Event Results; 5) Lean, Six Sigma, and Kaizen Practices in the Ares Projects Office; 6) Lean and Kaizen Success Stories; and 7) Ares Six Sigma Practices.

  19. LEAN thinking in Finnish healthcare.

    Science.gov (United States)

    Jorma, Tapani; Tiirinki, Hanna; Bloigu, Risto; Turkki, Leena

    2016-01-01

    Purpose - The purpose of this study is to evaluate how LEAN thinking is used as a management and development tool in the Finnish public healthcare system and what kind of outcomes have been achieved or expected by using it. The main focus is in managing and developing patient and treatment processes. Design/methodology/approach - A mixed-method approach incorporating the Webropol survey was used. Findings - LEAN is quite a new concept in Finnish public healthcare. It is mainly used as a development tool to seek financial savings and to improve the efficiency of patient processes, but has not yet been deeply implemented. However, the experiences from LEAN initiatives have been positive, and the methodology is already quite well-known. It can be concluded that, because of positive experiences from LEAN, the environment in Finnish healthcare is ready for the deeper implementation of LEAN. Originality/value - This paper evaluates the usage of LEAN thinking for the first time in the public healthcare system of Finland as a development tool and a management system. It highlights the implementation and achieved results of LEAN thinking when used in the healthcare environment. It also highlights the expectations for LEAN thinking in Finnish public healthcare.

  20. Burning Feet

    Science.gov (United States)

    ... be accompanied by a pins and needles sensation (paresthesia) or numbness, or both. Burning feet may also be referred to as tingling feet or paresthesia. While fatigue or a skin infection can cause ...

  1. The Role of Post Flame Oxidation on the UHC Emission for Combustion of Natural Gas and Hydrogen Containing fuels

    DEFF Research Database (Denmark)

    Jensen, Torben Kvist; Schramm, Jesper

    2003-01-01

    In-cylinder post flame oxidation of unburned hydro-carbons from crevices in a lean burn spark ignition engine has been examined for natural gas and mixtures of natural gas and a hydrogen containing producer gas. For this purpose a model was developed to describe the mixing of cold unburned...... reactants from crevices and hot burned bulk gas and to describe the oxidation of the unburned fuel. The post oxidation was described by a single step chemical reaction mechanism instead of detailed chemical kinetics in order to reduce the calculation time. However, the exploited Arrhenius expressions used...... to describe the chemical reactions were deduced from a detailed reaction mechanism. Different detailed reaction mechanisms were compared with results from combustion reactor experiments. Experiments and simulations were compared at different pressures and excesses of air similar to the conditions present...

  2. Burning issues

    International Nuclear Information System (INIS)

    Raloff, J.

    1993-01-01

    The idea of burning oil slicks at sea has intrigued oil-cleanup managers for more than a decade, but it wasn't until the advent of fireproof booms in the mid-1980's and a major spill opportunity (the March 1989 Exxon Valdez) that in-situ burning got a real sea trial. The results of this and other burning experiments indicate that, when conditions allow it, nothing can compete with fire's ability to remove oil from water. Burns have the potential to remove as much oil in one day as mechanical devices can in one month, along with minimal equipment, labor and cost. Reluctance to burn in appropriate situations comes primarily from the formation of oily, black smoke. Analysis of the potentially toxic gases have been done, indicating that burning will not increase the levels of polluting aldehydes, ketones, dioxins, furans, and PAHs above those that normally evaporate from spilled oil. This article contains descriptions of planned oil fires and the discussion on the advantages and concerns of such a policy

  3. Generating electricity and heat from lean gas. Dual fuel engine generates electricity and process heat from cupola furnace gas; Strom und Waerme aus Schwachgas gewinnen. Zuendstrahlmotor erzeugt Strom und Prozesswaerme aus Kupolofengas

    Energy Technology Data Exchange (ETDEWEB)

    Hirn, Gerhard

    2012-07-01

    White-hot molten iron flows into the launder. The blast of heat released provides visitors with an impressive demonstration of the amount of energy flowing in foundries. Large volumes of carbon (coke) are used for the melting process in the cupola furnace, whereby a combustible process gas is formed as a by-product. This so-called cupola furnace gas has a low heating value and has previously been completely combusted for generating the hot blast in the cupola furnace's recuperator. However, in this process only around 35 % of the contained energy is used thermally. Now it is possible to utilise the remaining 65 % of the chemically bound energy that was previously not used in most foundries: a modified biogas combined heat and power plant runs with cupola furnace gas (CFG) from the melting furnace. (orig.)

  4. Lean management beyond manufacturing a holistic approach

    CERN Document Server

    Bhasin, Sanjay

    2015-01-01

    Exploring Lean manufacturing in a holistic manner, this book helps organizations to implement Lean principles successfully by offering theoretical, empirical and practical knowledge. It empirically demonstrates how a successful Lean initiative can improve organizational efficiency, and incorporates valuable primary research to substantiate findings. It argues that Lean principles need to be applied throughout the value chain in order to be successful , and suggests that these tools need to be aligned with culture and change management. Chapters examine issues including Lean cultures, impediments to Lean, Lean and performance measurement, and the impact of Lean. Viewing Lean as a never-ending journey, this book provides a valuable resource to practising Lean managers, and specialist researchers and students, and also offers an important reference for organizations embarking on their Lean voyage.

  5. The Role of Post Flame Oxidation on the UHC Emission for Combustion of Natural Gas and Hydrogen Containing fuels

    DEFF Research Database (Denmark)

    Jensen, Torben Kvist; Schramm, Jesper

    2003-01-01

    In-cylinder post flame oxidation of unburned hydro-carbons from crevices in a lean burn spark ignition engine has been examined for natural gas and mixtures of natural gas and a hydrogen containing producer gas. For this purpose a model was developed to describe the mixing of cold unburned...... during in-cylinder post oxidation. The Arrhenius parameters were determined using the reaction mechanism, which gave the prediction of the results from the combustion reactor experiments. The investigation showed that addition of producer gas to natural gas promotes the in-cylinder post oxidation...... significantly. Furthermore it was found that the cyclic variation in the post oxidation is reduced by addition of producer gas to natural gas....

  6. Low-Load Limit in a Diesel-Ignited Gas Engine

    Directory of Open Access Journals (Sweden)

    Richard Hutter

    2017-09-01

    Full Text Available The lean-burn capability of the Diesel-ignited gas engine combined with its potential for high efficiency and low CO 2 emissions makes this engine concept one of the most promising alternative fuel converters for passenger cars. Instead of using a spark plug, the ignition relies on the compression-ignited Diesel fuel providing ignition centers for the homogeneous air-gas mixture. In this study the amount of Diesel is reduced to the minimum amount required for the desired ignition. The low-load operation of such an engine is known to be challenging, as hydrocarbon (HC emissions rise. The objective of this study is to develop optimal low-load operation strategies for the input variables equivalence ratio and exhaust gas recirculation (EGR rate. A physical engine model helps to investigate three important limitations, namely maximum acceptable HC emissions, minimal CO 2 reduction, and minimal exhaust gas temperature. An important finding is the fact that the high HC emissions under low-load and lean conditions are a consequence of the inability to raise the gas equivalence ratio resulting in a poor flame propagation. The simulations on the various low-load strategies reveal the conflicting demand of lean combustion with low CO 2 emissions and stoichiometric operation with low HC emissions, as well as the minimal feasible dual-fuel load of 3.2 bar brake mean effective pressure.

  7. Lean Startup and Lean Canvas Using for Innovative Product Development

    Directory of Open Access Journals (Sweden)

    Alena Buchalcevová

    2016-06-01

    Full Text Available Recently, new approaches to product development have emerged that focus on idea generation techniques and customer itself. One of them is the Lean Startup method that is described in this article along with the Lean Canvas method. The main goal of the article is to demonstrate the application of both methods to an innovative product development focused on providing interactive trips for families with children. The development of the product during individual phases is described and application of the Lean Startup and Lean Canvas principles is demonstrated. Finally, benefits of both methods contributing to the product success are discussed. Similar case studies start emerging worldwide, however in the Czech context are quite rare.

  8. Clinically lean; "cutting the crap".

    Science.gov (United States)

    Caldwell, G

    2012-01-01

    Proponents of Lean Philosophy believe that successful businesses must reduce waste in working time and resources to a minimum, and maximise their use in productive work. The productive work of the Acute Medical Unit is to provide effective clinical management to a daily cohort of acutely ill patients. Many Clinicians are cynical about Lean. In this article, Dr Caldwell discusses how many clinicians complain of too much crap in the workplace, which gets in the way of swift, safe high quality clinical care. He argues that "Cutting the Crap" in the Acute Medical Unit is entirely consistent with Lean approaches to management of complex systems.

  9. Improving healthcare using Lean processes.

    Science.gov (United States)

    Baker, G Ross

    2014-01-01

    For more than a decade, healthcare organizations across Canada have been using Lean management tools to improve care processes, reduce preventable adverse events, increase patient satisfaction and create better work environments. The largest system-wide effort in Canada, and perhaps anywhere, is currently under way in Saskatchewan. The jury is still out on whether Lean efforts in that province, or elsewhere in Canada, are robust enough to transform current delivery systems and sustain new levels of performance. This issue of Healthcare Quarterly features several articles that provide a perspective on Lean methods in healthcare. Copyright © 2014 Longwoods Publishing.

  10. Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment

    Science.gov (United States)

    Koss, Abigail R.; Sekimoto, Kanako; Gilman, Jessica B.; Selimovic, Vanessa; Coggon, Matthew M.; Zarzana, Kyle J.; Yuan, Bin; Lerner, Brian M.; Brown, Steven S.; Jimenez, Jose L.; Krechmer, Jordan; Roberts, James M.; Warneke, Carsten; Yokelson, Robert J.; de Gouw, Joost

    2018-03-01

    Volatile and intermediate-volatility non-methane organic gases (NMOGs) released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF). We identified NMOG contributors to more than 150 PTR ion masses using gas chromatography (GC) pre-separation with electron ionization, H3O+ chemical ionization, and NO+ chemical ionization, an extensive literature review, and time series correlation, providing higher certainty for ion identifications than has been previously available. Our interpretation of the PTR-ToF mass spectrum accounts for nearly 90 % of NMOG mass detected by PTR-ToF across all fuel types. The relative contributions of different NMOGs to individual exact ion masses are mostly similar across many fires and fuel types. The PTR-ToF measurements are compared to corresponding measurements from open-path Fourier transform infrared spectroscopy (OP-FTIR), broadband cavity-enhanced spectroscopy (ACES), and iodide ion chemical ionization mass spectrometry (I- CIMS) where possible. The majority of comparisons have slopes near 1 and values of the linear correlation coefficient, R2, of > 0.8, including compounds that are not frequently reported by PTR-MS such as ammonia, hydrogen cyanide (HCN), nitrous acid (HONO), and propene. The exceptions include methylglyoxal and compounds that are known to be difficult to measure with one or more of the deployed instruments. The fire-integrated emission ratios to CO and emission factors of NMOGs from 18 fuel types are provided. Finally, we provide an overview of the chemical characteristics of detected species. Non-aromatic oxygenated compounds are the most abundant. Furans and aromatics, while less abundant, comprise a large portion of the OH reactivity. The OH reactivity, its major contributors, and the volatility distribution of emissions can change considerably over the course of a fire.

  11. Non-methane organic gas emissions from biomass burning: identification, quantification, and emission factors from PTR-ToF during the FIREX 2016 laboratory experiment

    Directory of Open Access Journals (Sweden)

    A. R. Koss

    2018-03-01

    Full Text Available Volatile and intermediate-volatility non-methane organic gases (NMOGs released from biomass burning were measured during laboratory-simulated wildfires by proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF. We identified NMOG contributors to more than 150 PTR ion masses using gas chromatography (GC pre-separation with electron ionization, H3O+ chemical ionization, and NO+ chemical ionization, an extensive literature review, and time series correlation, providing higher certainty for ion identifications than has been previously available. Our interpretation of the PTR-ToF mass spectrum accounts for nearly 90 % of NMOG mass detected by PTR-ToF across all fuel types. The relative contributions of different NMOGs to individual exact ion masses are mostly similar across many fires and fuel types. The PTR-ToF measurements are compared to corresponding measurements from open-path Fourier transform infrared spectroscopy (OP-FTIR, broadband cavity-enhanced spectroscopy (ACES, and iodide ion chemical ionization mass spectrometry (I− CIMS where possible. The majority of comparisons have slopes near 1 and values of the linear correlation coefficient, R2, of  >  0.8, including compounds that are not frequently reported by PTR-MS such as ammonia, hydrogen cyanide (HCN, nitrous acid (HONO, and propene. The exceptions include methylglyoxal and compounds that are known to be difficult to measure with one or more of the deployed instruments. The fire-integrated emission ratios to CO and emission factors of NMOGs from 18 fuel types are provided. Finally, we provide an overview of the chemical characteristics of detected species. Non-aromatic oxygenated compounds are the most abundant. Furans and aromatics, while less abundant, comprise a large portion of the OH reactivity. The OH reactivity, its major contributors, and the volatility distribution of emissions can change considerably over the course of a fire.

  12. NOx reduction and NO2 emission characteristics in rich-lean combustion of hydrogen

    OpenAIRE

    Shudo, Toshio; Omori, Kento; Hiyama, Osamu

    2008-01-01

    Hydrogen is a clean alternative to conventional hydrocarbon fuels, but it is very important to reduce the nitrogen oxides (NOx) emissions generated by hydrogen combustion. The rich-lean combustion or staged combustion is known to reduce NOx emissions from continuous combustion burners such as gas turbines and boilers, and NOx reduction effects have been demonstrated for hydrocarbon fuels. The authors applied rich-lean combustion to a hydrogen gas turbine and showed its NOx reduction effect in...

  13. Lean Manufacturing measurement: The relationships between Lean activities and Lean metrics

    Directory of Open Access Journals (Sweden)

    Diego Fernando Manotas Duque

    2007-01-01

    Full Text Available Medición en Lean Manufacturing: Relaciones entre Actividades Lean y Métricas Lean Lean Manufacturing fue desarrollada por Toyota para satisfacer sus necesidades específicas en un mercado restringido y en tiempos de estrechez económica. Estos conceptos han sido estudiados y se ha comprobado su aplicabilidad en una amplia variedad de industrias. El objetivo de este artículo es el de integrar un conjunto de métricas que han sido propuestas por diferentes autores, de tal manera que sean consistentes con las etapas y elementos de implementaciones de Lean Manufacturing. Para lograrlo se presentan dos marcos de referencia para implementaciones Lean y los principales factores de éxito se utilizan como base para proponer métricas que identifiquen el avance en estos factores. Posteriormente se propone una tabla que cruza el impacto de las “Actividades Lean” sobre las métricas, postulando que muchos de los supuestos a priori sobre estos impactos deberían ser precisos. Finalmente se proponen algunas ideas para proyectos de investigación hacia el futuro y posibles extensiones de las aplicaciones propuestas aquí.

  14. Adapting the deep burn in-core fuel management strategy for the gas turbine - modular helium reactor to a uranium-thorium fuel

    Energy Technology Data Exchange (ETDEWEB)

    Talamo, Alberto [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)]. E-mail: alby@neutron.kth.se; Gudowski, Waclaw [Department of Nuclear and Reactor Physics, Royal Institute of Technology, Roslagstullsbacken 21, S-10691, Stockholm (Sweden)

    2005-11-15

    In 1966, Philadelphia Electric has put into operation the Peach Bottom I nuclear reactor, it was the first high temperature gas reactor (HTGR); the pioneering of the helium-cooled and graphite-moderated power reactors continued with the Fort St. Vrain and THTR reactors, which operated until 1989. The experience on HTGRs lead General Atomics to design the gas turbine - modular helium reactor (GT-MHR), which adapts the previous HTGRs to the generation IV of nuclear reactors. One of the major benefits of the GT-MHR is the ability to work on the most different types of fuels: light water reactors waste, military plutonium, MOX and thorium. In this work, we focused on the last type of fuel and we propose a mixture of 40% thorium and 60% uranium. In a uranium-thorium fuel, three fissile isotopes mainly sustain the criticality of the reactor: {sup 235}U, which represents the 20% of the fresh uranium, {sup 233}U, which is produced by the transmutation of fertile {sup 232}Th, and {sup 239}Pu, which is produced by the transmutation of fertile {sup 238}U. In order to compensate the depletion of {sup 235}U with the breeding of {sup 233}U and {sup 239}Pu, the quantity of fertile nuclides must be much larger than that one of {sup 235}U because of the small capture cross-section of the fertile nuclides, in the thermal neutron energy range, compared to that one of {sup 235}U. At the same time, the amount of {sup 235}U must be large enough to set the criticality condition of the reactor. The simultaneous satisfaction of the two above constrains induces the necessity to load the reactor with a huge mass of fuel; that is accomplished by equipping the fuel pins with the JAERI TRISO particles. We start the operation of the reactor with loading fresh fuel into all the three rings of the GT-MHR and after 810 days we initiate a refueling and shuffling schedule that, in 9 irradiation periods, approaches the equilibrium of the fuel composition. The analysis of the k {sub eff} and mass

  15. Adapting the deep burn in-core fuel management strategy for the gas turbine - modular helium reactor to a uranium-thorium fuel

    International Nuclear Information System (INIS)

    Talamo, Alberto; Gudowski, Waclaw

    2005-01-01

    In 1966, Philadelphia Electric has put into operation the Peach Bottom I nuclear reactor, it was the first high temperature gas reactor (HTGR); the pioneering of the helium-cooled and graphite-moderated power reactors continued with the Fort St. Vrain and THTR reactors, which operated until 1989. The experience on HTGRs lead General Atomics to design the gas turbine - modular helium reactor (GT-MHR), which adapts the previous HTGRs to the generation IV of nuclear reactors. One of the major benefits of the GT-MHR is the ability to work on the most different types of fuels: light water reactors waste, military plutonium, MOX and thorium. In this work, we focused on the last type of fuel and we propose a mixture of 40% thorium and 60% uranium. In a uranium-thorium fuel, three fissile isotopes mainly sustain the criticality of the reactor: 235 U, which represents the 20% of the fresh uranium, 233 U, which is produced by the transmutation of fertile 232 Th, and 239 Pu, which is produced by the transmutation of fertile 238 U. In order to compensate the depletion of 235 U with the breeding of 233 U and 239 Pu, the quantity of fertile nuclides must be much larger than that one of 235 U because of the small capture cross-section of the fertile nuclides, in the thermal neutron energy range, compared to that one of 235 U. At the same time, the amount of 235 U must be large enough to set the criticality condition of the reactor. The simultaneous satisfaction of the two above constrains induces the necessity to load the reactor with a huge mass of fuel; that is accomplished by equipping the fuel pins with the JAERI TRISO particles. We start the operation of the reactor with loading fresh fuel into all the three rings of the GT-MHR and after 810 days we initiate a refueling and shuffling schedule that, in 9 irradiation periods, approaches the equilibrium of the fuel composition. The analysis of the k eff and mass evolution, reaction rates, neutron flux and spectrum at the

  16. Two-stage combustion for reducing pollutant emissions from gas turbine combustors

    Science.gov (United States)

    Clayton, R. M.; Lewis, D. H.

    1981-01-01

    Combustion and emission results are presented for a premix combustor fueled with admixtures of JP5 with neat H2 and of JP5 with simulated partial-oxidation product gas. The combustor was operated with inlet-air state conditions typical of cruise power for high performance aviation engines. Ultralow NOx, CO and HC emissions and extended lean burning limits were achieved simultaneously. Laboratory scale studies of the non-catalyzed rich-burning characteristics of several paraffin-series hydrocarbon fuels and of JP5 showed sooting limits at equivalence ratios of about 2.0 and that in order to achieve very rich sootless burning it is necessary to premix the reactants thoroughly and to use high levels of air preheat. The application of two-stage combustion for the reduction of fuel NOx was reviewed. An experimental combustor designed and constructed for two-stage combustion experiments is described.

  17. Researching Lean: Methodological Implications of Loose Definitions

    Directory of Open Access Journals (Sweden)

    Mikael Brännmark

    2012-12-01

    Full Text Available Recently, Lean Production (Lean has become a prevailing management concept in Sweden. However, previous research seems to show that the Lean concept and the impact of Lean vary considerably between organizations. This paper illustrates some key methodological issues that need to be considered when researching loosely defined management concepts such as Lean. The paper is based on a review of the literature and five comparative Swedish cases studies. Our study indicates that Lean has changed over time and that operationalization and interpretations of the concept vary considerably. This study concludes that future Lean studies should include a thorough assessment of the Lean interventions, study settings, and in particular non-Lean factors mediating the outcomes of Lean-inspired change programs.

  18. Lean Design and Management for Manufactoring

    OpenAIRE

    NIU, Zhanwen

    2009-01-01

    Most enterprises inducting lean production were confined by the innate limitations of existing production systems, which make it difficult to fulfill lean production comprehensively. To solve this problem, the theory of lean design and management for the manufacturing enterprise lifecycle was proposed. First, the necessities of lean design were analyzed and its theoretical system was established; second, the principles, process, methods and tools for lean design was introduced. Techniques and...

  19. The evolution of Lean organizations

    OpenAIRE

    Serafinas, Dalius; Ruželė, Darius

    2014-01-01

    Remiantis evoliucijos tyrimų modeliais bei autorių sudarytu evoliucionuojančios organizacijos modeliu,straipsnyje analizuojama Lean vadybos metodologija ir tiriama, kaip evoliucionuoja ją įgyvendinančios Lietuvosgamybinės organizacijos. The purpose of this paper is to examine the evolution of Lean organizations.Design/methodology/approach: a conceptual literature on the evolution of species, organisms and organizations was reviewed and an original model (framework) of the evolution of orga...

  20. Buildings Lean Maintenance Implementation Model

    Science.gov (United States)

    Abreu, Antonio; Calado, João; Requeijo, José

    2016-11-01

    Nowadays, companies in global markets have to achieve high levels of performance and competitiveness to stay "alive".Within this assumption, the building maintenance cannot be done in a casual and improvised way due to the costs related. Starting with some discussion about lean management and building maintenance, this paper introduces a model to support the Lean Building Maintenance (LBM) approach. Finally based on a real case study from a Portuguese company, the benefits, challenges and difficulties are presented and discussed.

  1. Lean Transformation of Multinational Concerns

    DEFF Research Database (Denmark)

    Matthiesen, Rikke Vestergaard; Johansen, John

    2008-01-01

    triggered. This paper reports on exploratory studies from a multinational company adopting centrally managed pilot projects as a transformation mechanism for continuous change towards a lean business system and an organizational culture of continuous improvements (CI). Competitive pressure demands...... from a multinational company adopting centrally managed pilot projects as a transformation mechanism for continuous change towards a lean business system and an organizational culture of continuous improvements (CI)....

  2. Evaluation and development of direct burning natural gas industrial equipment in the food sector; Avaliacao e desenvolvimento de equipamentos industriais de queima direta de gas natural no setor de alimentos

    Energy Technology Data Exchange (ETDEWEB)

    Schwob, Marcelo; Morales, Maria Elizabeth; Henriques, Mauricio; Guimaraes, Marcio; Tapia, Roberto; Rodrigues, Joaquim; Faccion, Alexandre [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil)

    2004-07-01

    The aim of this study, focused in the food sector, is evaluate and develop technologies used in equipment of direct burning natural gas, as ovens and driers of common use in the toasting coffee, noodles and biscuits industries. We have developed an archetype of oven for baking, seeking to incorporate new technological concepts but showing operational conditions of great attractiveness for the users of this kind of equipment. Above all, aiming the optimization of the technologies to improve the energy efficiency, to reduce costs and to increase the operational security. Thus, a survey of the thermal equipment in the mentioned industrial sector was made, followed of an evaluation of the technical possibilities of its incorporation in that sector, adaptations and the modifications of engineering projects, identifying the possibilities of productivity increase, improvement of quality and greater competitiveness, as well as the reduction of atmospheric emissions. So, It has been proposed solutions as the decentralized use of the thermal energy, recovery of heat of exhaustion gases, optimization of the thermal insulation, reduction of thermal inertia and the automatization of the control of the combustion in ovens and/or driers of the mentioned sectors. The main results of this study are: the possibility of reduction of, 32 to 37% in the consumption of thermal energy in the ovens of biscuit production, of 12 to 15% in the toasting of coffee and 20 to 30% in the processes of noodles production. Saving of around 25% would be expected in the small bearing ovens for baking. (author)

  3. Wood burning

    Energy Technology Data Exchange (ETDEWEB)

    Winkelmann, H

    1955-01-01

    Discussed are the use of wood as a fuel, the technique of wood combustion and the operation of wood-burning stoves for cooking and heating. In addition, there is a section which reviews the use of wood stoves in various countries and lists manufacturers of stoves, central heating furnaces and in some cases sawdust burners.

  4. Modelling of thermal mechanical behaviour of high burn-Up VVER fuel at power transients with special emphasis on the impact of fission gas induced swelling of fuel pellets

    International Nuclear Information System (INIS)

    Novikov, V.; Medvedev, A.; Khvostov, G.; Bogatyr, S.; Kuzetsov, V.; Korystin, L.

    2005-01-01

    This paper is devoted to the modelling of unsteady state mechanical and thermo-physical behaviour of high burn-up VVER fuel at a power ramp. The contribution of the processes related to the kinetics of fission gas to the consequences of pellet-clad mechanical interaction is analysed by the example of integral VVER-440 rod 9 from the R7 experimental series, with a pellet burn-up in the active part at around 60 MWd/kgU. This fuel rod incurred ramp testing with a ramp value ΔW 1 ∼ 250 W/cm in the MIR research reactor. The experimentally revealed residual deformation of the clad by 30-40 microns in the 'hottest' portion of the rod, reaching a maximum linear power of up to 430 W/cm, is numerically justified on the basis of accounting for the unsteady state swelling and additional degradation of fuel thermal conductivity due to temperature-induced formation and development of gaseous porosity within the grains and on the grain boundaries. The good prediction capability of the START-3 code, coupled with the advanced model of fission gas related processes, with regard to the important mechanical (residual deformation of clad, pellet-clad gap size, central hole filling), thermal physical (fission gas release) and micro-structural (profiles of intra-granular concentration of the retained fission gas and fuel porosity across a pellet) consequences of the R7 test is shown. (authors)

  5. Performance of a hydrogen-enriched ethanol engine at unthrottled and lean conditions

    International Nuclear Information System (INIS)

    Zhang, Bo; Ji, Changwei; Wang, Shuofeng

    2016-01-01

    Highlights: • H_2 addition eased cyclic variation of ethanol engine at unthrottled condition. • H_2-blended ethanol engine gains better efficiency at lean conditions. • Bmep of H_2-blended ethanol engine could be controlled by lean burning. • H_2 addition results in reduced exhaust loss and HC emissions. - Abstract: Concerning the throttling loss under part load conditions, it is feasible to further improve the engine thermal efficiency through operating the engine under the unthrottled condition and controlling its load by changing the excess air ratio. However, the narrow flammability of ethanol may lead the ethanol engine to encounter high cyclic variations under unthrottled and lean conditions. The addition of hydrogen is potentially helpful for solving this problem. In this test, the engine was run under an speed of 1400 rpm and unthrottled conditions. The hydrogen volume fractions in the intake were respectively kept at 0% and 3%. For a given hydrogen blending level, the ethanol flow rate was reduced to enable the engine to run under lean conditions. The results showed that the engine efficiency was improved with the blending of hydrogen. The highest thermal efficiency was improved by 6.07% after blending 3% hydrogen to the intake air. The addition of hydrogen could increase the engine torque output at lean conditions. Both cooling and exhaust losses were decreased after the hydrogen enrichment while adopting the lean combustion strategy. The hydrogen addition contributed to the extended lean burn limit and decreased cyclic variation under lean conditions. HC and CO emissions were decreased whereas NOx emissions were increased after the blending of hydrogen.

  6. Educational Materials - Burn Wise

    Science.gov (United States)

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  7. Lean manufacturing measurement: the relationship between lean activities and lean metrics

    Directory of Open Access Journals (Sweden)

    Manotas Duque Diego Fernando

    2007-10-01

    Full Text Available Lean Manufacturing was developed by Toyota Motor company to address their specific needs in a restricted market in times of economic trouble. These concepts have been studied and proven to be transferrable and applicable to a wide variety of industries. This paper aims to integrate a set of metrics that have been proposed by different authors in such a way that they are consistent with the different stages and elements of Lean Manufacturing implementations. To achieve this, two frameworks for Lean implementations are presented and then the main factors for success are used as the basis to propose metrics that measure the advance in these factors. A tabular display of the impact of “Lean activities” on the metrics is presented, proposing that many a priori assumptions about the benefits on many different levels of improvement should be accurate. Finally, some ideas for future research and extension of the applications proposed on this paper are presented as closing points.

  8. Effect of Soret diffusion on lean hydrogen/air flames at normal and elevated pressure and temperature

    KAUST Repository

    Zhou, Zhen; Hernandez Perez, Francisco; Shoshin, Yuriy; van Oijen, Jeroen A.; de Goey, Laurentius P.H.

    2017-01-01

    The influence of Soret diffusion on lean premixed flames propagating in hydrogen/air mixtures is numerically investigated with a detailed chemical and transport models at normal and elevated pressure and temperature. The Soret diffusion influence on the one-dimensional (1D) flame mass burning rate and two-dimensional (2D) flame propagating characteristics is analysed, revealing a strong dependency on flame stretch rate, pressure and temperature. For 1D flames, at normal pressure and temperature, with an increase of Karlovitz number from 0 to 0.4, the mass burning rate is first reduced and then enhanced by Soret diffusion of H2 while it is reduced by Soret diffusion of H. The influence of Soret diffusion of H2 is enhanced by pressure and reduced by temperature. On the contrary, the influence of Soret diffusion of H is reduced by pressure and enhanced by temperature. For 2D flames, at normal pressure and temperature, during the early phase of flame evolution, flames with Soret diffusion display more curved flame cells. Pressure enhances this effect, while temperature reduces it. The influence of Soret diffusion of H2 on the global consumption speed is enhanced at elevated pressure. The influence of Soret diffusion of H on the global consumption speed is enhanced at elevated temperature. The flame evolution is more affected by Soret diffusion in the early phase of propagation than in the long run due to the local enrichment of H2 caused by flame curvature effects. The present study provides new insights into the Soret diffusion effect on the characteristics of lean hydrogen/air flames at conditions that are relevant to practical applications, e.g. gas engines and turbines.

  9. Effect of Soret diffusion on lean hydrogen/air flames at normal and elevated pressure and temperature

    KAUST Repository

    Zhou, Zhen

    2017-04-12

    The influence of Soret diffusion on lean premixed flames propagating in hydrogen/air mixtures is numerically investigated with a detailed chemical and transport models at normal and elevated pressure and temperature. The Soret diffusion influence on the one-dimensional (1D) flame mass burning rate and two-dimensional (2D) flame propagating characteristics is analysed, revealing a strong dependency on flame stretch rate, pressure and temperature. For 1D flames, at normal pressure and temperature, with an increase of Karlovitz number from 0 to 0.4, the mass burning rate is first reduced and then enhanced by Soret diffusion of H2 while it is reduced by Soret diffusion of H. The influence of Soret diffusion of H2 is enhanced by pressure and reduced by temperature. On the contrary, the influence of Soret diffusion of H is reduced by pressure and enhanced by temperature. For 2D flames, at normal pressure and temperature, during the early phase of flame evolution, flames with Soret diffusion display more curved flame cells. Pressure enhances this effect, while temperature reduces it. The influence of Soret diffusion of H2 on the global consumption speed is enhanced at elevated pressure. The influence of Soret diffusion of H on the global consumption speed is enhanced at elevated temperature. The flame evolution is more affected by Soret diffusion in the early phase of propagation than in the long run due to the local enrichment of H2 caused by flame curvature effects. The present study provides new insights into the Soret diffusion effect on the characteristics of lean hydrogen/air flames at conditions that are relevant to practical applications, e.g. gas engines and turbines.

  10. Emissão de mercúrio para a atmosfera pela queima de gás natural no Brasil Mercury emissions to the atmosphere from natural gas burning in Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Drude de Lacerda

    2007-04-01

    Full Text Available Increasing natural gas use in Brazil triggered a discussion of its role as a Hg source. We show that Hg emissions to the atmosphere from fossil fuel combustion for power generation in Brazil contribute with 6.2% (4.2 t yr-1 to the total anthropogenic Hg atmospheric emissions, with coal combustion and biomass burning as major sources. Natural gas contributes with 0.04 t yr-1, mostly from electricity generation (88% and industrial uses (7.6%. Preliminary results on Hg concentrations in natural gas suggest that a large fraction of it is trapped during refining and transport, which may create Hg point sources between extraction and consumption.

  11. Investigation of fuel lean reburning process in a 1.5 MW boiler

    International Nuclear Information System (INIS)

    Kim, Hak Young; Baek, Seung Wook; Kim, Se Won

    2012-01-01

    Highlights: → We examine a detailed study of fuel lean reburning process in a 1.5 MW gas-fired boiler. → Experimental and numerical researches are conducted. → We investigate change in the level of NO X and CO emission. → The recirculation flow is important in the fuel lean reburning process. -- Abstract: This paper examines a detailed study of fuel lean reburning process applied to a 1.5 MW gas-fired boiler. Experimental and numerical studies were carried out to investigate the effect of the fuel lean reburning process on the NO X reduction and CO emission. Natural gas (CH 4 ) was used as the reburn as well as the main fuel. The amount of the reburn fuel, injection location and thermal load of boiler were considered as experimental parameters. The flue gas data revealed that the fuel lean reburning process led to NO X reduction up to 43%, while CO emission was limited to less than 30 ppm for the 100% thermal load condition. The commercial computational fluid dynamics code FLUENT 6.3, which included turbulence, chemical reaction, radiation and NO modeling, was used to predict the fluid flow and heat transfer characteristics under various operational conditions in the boiler. Subsequently, predicted results were validated with available measured data such as gas temperature distributions and local mean NO X concentrations. The detailed numerical results showed that the recirculation flow developed inside the boiler was found to play an important role in improving the effectiveness of fuel lean reburning process.

  12. Lean versus Quick Response Manufacturing og andre koncepter - er Lean den eneste ene?

    DEFF Research Database (Denmark)

    Michelsen, Aage U

    2005-01-01

    Begrebet Lean har gennem de senere år vundet en enorm udbredelse. Antallet af publikationer om Lean har været eksplosivt stigende, og mange virksomheder har gennemført eller gennemfører Lean-projekter. Er Lean et nyt koncept? Er Lean den eneste løsning? Kan Lean kombineres med tankegange og princ...... løsning af en anden produktionsopgave. I fjerde afsnit skitseres kort relationerne mellem Lean og to andre begreber, Six Sigma og TPM, der begge har samme mål som Lean, men forskellige udgangspunkter og forskellige indfaldsvinkler....

  13. Potentiel des moteurs à mélange pauvre face aux moteurs actuels à réglage stoechiométrique : consommation, émissions, exigence en octane The Challenge to Modern Stoichiometric Engines by the Potential Lean-Burn Engine: Consumption, Emissions, Fuel Requirements

    Directory of Open Access Journals (Sweden)

    Douaud A. M.

    2006-11-01

    Full Text Available Le moteur à allumage commandé pour application automobile aux États-Unis est généralement dépollué par catalyse trifonctionnelle qui impose un contrôle stoechiométrique du mélange air-carburant. Le contexte européen de 1990 pour la qualité de l'air stimule l'industrie automobile dans ses recherches de solutions techniques performantes. Le moteur à mélange pauvre, performant en consommation, est une solution potentielle si l'émission de NOx peut être maîtrisée par la combustion. Cet objectif nécessite une conception du moteur contrôlant la turbulence et l'hétérogénéité du mélange air + carburant + résiduels pendant la combustion. La longévité de l'adaptation optimale moteur-carburant nécessitera un contrôle électronique de l'allumage et l'utilisation d'additifs détergents. Pour satisfaire les réglementations les plus sévères, les émissions de CO et HC pourront être contrôlées par un simple pot catalytique d'oxydation. Des oxydes de métaux non précieux introduits dans la formule catalytique en addition aux métaux précieux maintiennent la fonction oxydante pendant les transitoires en mélange riche tout en réduisant partiellement les NOx. Une vue d'ensemble de ce concept basé sur des simulations numériques et des résultats expérimentaux de consommation, d'émission, d'exigence en octane, etc. est présentée. Spark-ignition engines for automotive applications in the United States are currently depolluted by a 3-way catalyst that requires air-fuel control at stoichiometry. The 1990 European context for air pollution control is stimulating the automotive industry to search for improved technical solutions. The lean-burn engine is a potential fuel-efficient answer if its combustion can be optimized for low NOx emissions. Achieving this challenging approach requires engine design to control the turbulence and heterogeneity of the air + fuel + residual mixture during combustion. Electronic ignition

  14. Lean Production Applications in a Manufacturing Company

    OpenAIRE

    Ali Görener; Humeyra Baser; Ali Turkyilmaz

    2013-01-01

    Lean production is a production model which comes about the pursuit of companies to be able to meet competition and make effective production. The main purpose of lean production is to get control about the wastage. This study includes the requirements for the success of the lean production and how the lean production system can be established. In this paper, lean production techniques were applied to the electric water heater line. Measurements using lean initiatives were made, operation cyc...

  15. Contractor Work Preparation Process Improvement Using Lean Six Sigma

    Directory of Open Access Journals (Sweden)

    Asana Kusnadi

    2016-06-01

    Full Text Available To ensure the health and safety of their workforce and protection of their assets and the environment, a global oil and gas company operating in Indonesia requires comprehensive identification and evaluation of job hazards that were included in work permitting process prior work execution in the field. Based on 20 data points obtained in August 2013, start-working time for contractors who worked for Capital Project Management (CPM Team in Facility B was in average at 09.05 a.m. The aim of this paper is to present how the firm implemented Lean Six Sigma to reduce non-added value activities while fulfilling to its safety requirements and to share lessons learned from practical and theory testing perspective. The methodology used is Lean Six Sigma’s DMAIC (Define, Measure, Analyze, Improve, Control as mandated by the corporate policy of the firm. This research adopts a mix-methods approach, by using both qualitative and quantitative data. This study was a one year longitudinal study of the Lean Six Sigma implementation to improve contractors’ work preparation process. The improvement resulted in reduction of non-value added activities and successfully increased the available working time per day by 59.3 minutes in average. The results of this case study reconfirm Lean Six Sigma as a good management theory since it shows a consistency between the theory and the real practice in a global oil and gas company in Indonesia.

  16. Lean computing for the cloud

    CERN Document Server

    Bauer, Eric

    2016-01-01

    Applies lean manufacturing principles across the cloud service delivery chain to enable application and infrastructure service providers to sustainably achieve the shortest lead time, best quality, and value This book focuses on lean in the context of cloud computing capacity management of applications and the physical and virtual cloud resources that support them. Lean Computing for the Cloud considers business, architectural and operational aspects of efficiently delivering valuable services to end users via cloud-based applications hosted on shared cloud infrastructure. The work also focuses on overall optimization of the service delivery chain to enable both application service and infrastructure service providers to adopt leaner, demand driven operations to serve end users more efficiently. The book’s early chapters analyze how capacity management morphs with cloud computing into interlocked physical infrastructure capacity management, virtual resou ce capacity management, and application capacity ma...

  17. Lean management in academic surgery.

    Science.gov (United States)

    Collar, Ryan M; Shuman, Andrew G; Feiner, Sandra; McGonegal, Amy K; Heidel, Natalie; Duck, Mary; McLean, Scott A; Billi, John E; Healy, David W; Bradford, Carol R

    2012-06-01

    Lean is a management system designed to enhance productivity by eliminating waste. Surgical practice offers many opportunities for improving efficiency. Our objective was to determine whether systematic implementation of lean thinking in an academic otolaryngology operating room improves efficiency and profitability and preserves team morale and educational opportunities. In an 18-month prospective quasi-experimental study, a multidisciplinary task force systematically implemented lean thinking within an otolaryngology operating room of an academic health system. Operating room turnover time and turnaround time were measured during a baseline period; an observer-effect period in which workers were made aware that their efficiency was being measured but before implementing lean changes; and an intervention period after redesign principles had been used. The impact on teamwork, morale, and surgical resident education were measured during the baseline and intervention periods through validated surveys. A profit model was applied to estimate the financial implications of the study. There was no difference between the baseline and observer-effect periods of the study for turnover time (p = 0.98) or turnaround time (p = 0.20). During the intervention period, the mean turnover time and turnaround time were significantly shorter than during the baseline period (29 vs 38 minutes; p improved morale after implementation (p = 0.011). Educational metrics were unchanged before and after implementation. The annual opportunity revenue for the involved operating room is $330,000; when extrapolated throughout the operating rooms, lean thinking could create 6,500 hours of capacity annually. Application of lean management techniques to a single operating room and surgical service improved operating room efficiency and morale, sustained resident education, and can provide considerable financial gains when scaled to an entire academic surgical suite. Copyright © 2012. Published by

  18. Characterization of Lean Misfire Limits of Mixture Alternative Gaseous Fuels Used for Spark Ignition Engines

    Directory of Open Access Journals (Sweden)

    Miqdam Tariq Chaichan

    2012-03-01

    Full Text Available Increasing on gaseous fuels as clean, economical and abundant fuels encourages the search for optimum conditions of gas-fueled internal combustion engines. This paper presents the experimental results on the lean operational limits of Recardo E6 engine using gasoline, LPG, NG and hydrogen as fuels. The first appearance of almost motoring cycle was used to define the engine lean limit after the fuel flow was reduced gradually. The effects of compression ratio, engine speed and spark timing on the engine operational limits are presented and discussed in detailed. Increasing compression ratio (CR extend the lean limits, this appears obviously with hydrogen, which has a wide range of equivalence ratios, while for hydrocarbon fuel octane number affect gasoline, so it can' t work above CR=9:1, and for LPG it reaches CR=12:1, NG reaches CR=15:1 at lean limit operation. Movement from low speeds to medium speeds extended lean misfire limits, while moving from medium to high speeds contracted the lean misfiring limits. NOx, CO and UBHC concentrations increased with CR increase for all fuels, while CO2 concentrations reduced with this increment. NOx concentration increased for medium speeds and reduced for high speeds, but the resulted concentrations were inconcedrable for these lean limits. CO and CO2 increased with engine speed increase, while UBHC reduced with this increment. The hydrogen engine runs with zero CO, CO2 and UNHC concentrations, and altra low levels of NOx concentrations at studied lean misfire limits

  19. Lean spare parts delivery chain

    OpenAIRE

    Sjöstrand, Niklas; Larsson, Mona-Liza

    2015-01-01

    AbstractWhen a product has been sold to a customer a new market arises for the company to earn profit from and to differentiate itself within. According to Bartwal, et al. (2010) the after sales market generally does not provide great revenues but good profits of the total revenue. In order to gain competiveness and live up to customer’s expectations a company needs to be efficient (Atkinson, 2004). He continuous that this can be accomplished if companies implement Lean. Lean is different too...

  20. 'Lean' approach gives greater efficiency.

    Science.gov (United States)

    Call, Roger

    2014-02-01

    Adapting the 'Lean' methodologies used for many years by many manufacturers on the production line - such as in the automotive industry - and deploying them in healthcare 'spaces' can, Roger Call, an architect at Herman Miller Healthcare in the US, argues, 'easily remedy many of the inefficiencies' found within a healthcare facility. In an article that first appeared in the September 2013 issue of The Australian Hospital Engineer, he explains how 'Lean' approaches such as the 'Toyota production system', and 'Six Sigma', can be harnessed to good effect in the healthcare sphere.

  1. A Simulation of Lean Manufacturing: The Lean Lemonade Tycoon 2

    Science.gov (United States)

    Ncube, Lisa B.

    2010-01-01

    This article discusses the functions and effectiveness of games and simulations in the learning processes, in particular as an experiential learning methodology. The application of the game Lemonade Tycoon in the development of lean manufacturing concepts is described. This article addresses the use of the game to teach the principles of lean…

  2. Learning Lean: A Survey of Industry Lean Needs

    Science.gov (United States)

    Fliedner, Gene; Mathieson, Kieran

    2009-01-01

    The authors examined business practitioners' preferences for higher education curricula design in general and for what graduates should know about Lean, or waste-reduction efforts. The authors conducted a Web-based survey and found that practitioners are not as concerned about graduates' possessing specific technical skills as they are about them…

  3. Lean Application to Manufacturing Ramp-Up

    DEFF Research Database (Denmark)

    Christensen, Irene; Rymaszewska, Anna

    2016-01-01

    . Abstracting from the extant literature, the authors considered the competitiveness of manufacturing companies from two principal perspectives: the leanness of the ramp-up process and the new-value creation of quality managers. While much of the literature fails to acknowledge that the roots of lean actually......This article provides a theoretical overview of the concepts of lean and manufacturing ramp-up in an attempt to conceptualize the strategic areas in which lean philosophy and principles can be applied for continuous improvements. The application of lean principles during the final stage of a new...... product development process, that is, the ramp-up process, is a critical, early enabler of lean manufacturing. The manufacturing strategy literature conceptualizes a state of “leanness in operations,” which can consolidate both the concepts of lean and manufacturing ramp-up, providing a dual perspective...

  4. A Sand Cone Model of Lean Implementation

    OpenAIRE

    Yestemessov, Azamat

    2011-01-01

    Over the past 20 years Lean Production system has been a focus of researches by different academicians. A numerous works have been written in the field of Lean implementation in manufacturing companies. However, as shown, most of the academic topics relate to the issues of implementing Lean tools and techniques. Critical Success Factors have been also described widely; however, no efforts in systematization have been made. Only several works have a focus on integration of Lean implementation ...

  5. Performance Improvement through Implementation of Lean Maintenance

    OpenAIRE

    S. Kolanjiappan; Dr. K. Maran

    2011-01-01

    Lean Maintenance is a relatively new term, invented in the last decade of the twentieth century, but the principles are well established in Total Productive Maintenance (TPM). Lean Maintenance—taking its lead from Lean Manufacturing—applies some new techniques to TPM concepts to render a more structured implementation path. Tracing its roots back to Henry Ford with modern refinements born in Japanese manufacturing, specifically the Toyota Production System (TPS). Lean seeks to eliminate a...

  6. Training for successful lean manufacturing implementation

    OpenAIRE

    Ichimura, Maki; Jahankhani, Hamid; Arunachalam, Subramaniam

    2006-01-01

    Implementing lean manufacturing is a complex and everlasting task. The workers involving in production processes are the pivot of the lean manufacturing implementation. Training is known as a vehicle to assist the implementation process. Despite awareness of the training importance, so far, a little is available to assist to organise an efficient training. This paper summarises the overview of lean manufacturing and discuss the importance of human resource within lean implementation process. ...

  7. Review of modern low emissions combustion technologies for aero gas turbine engines

    Science.gov (United States)

    Liu, Yize; Sun, Xiaoxiao; Sethi, Vishal; Nalianda, Devaiah; Li, Yi-Guang; Wang, Lu

    2017-10-01

    Pollutant emissions from aircraft in the vicinity of airports and at altitude are of great public concern due to their impact on environment and human health. The legislations aimed at limiting aircraft emissions have become more stringent over the past few decades. This has resulted in an urgent need to develop low emissions combustors in order to meet legislative requirements and reduce the impact of civil aviation on the environment. This article provides a comprehensive review of low emissions combustion technologies for modern aero gas turbines. The review considers current high Technologies Readiness Level (TRL) technologies including Rich-Burn Quick-quench Lean-burn (RQL), Double Annular Combustor (DAC), Twin Annular Premixing Swirler combustors (TAPS), Lean Direct Injection (LDI). It further reviews some of the advanced technologies at lower TRL. These include NASA multi-point LDI, Lean Premixed Prevaporised (LPP), Axially Staged Combustors (ASC) and Variable Geometry Combustors (VGC). The focus of the review is placed on working principles, a review of the key technologies (includes the key technology features, methods of realising the technology, associated technology advantages and design challenges, progress in development), technology application and emissions mitigation potential. The article concludes the technology review by providing a technology evaluation matrix based on a number of combustion performance criteria including altitude relight auto-ignition flashback, combustion stability, combustion efficiency, pressure loss, size and weight, liner life and exit temperature distribution.

  8. Burning plasmas

    International Nuclear Information System (INIS)

    Furth, H.P.; Goldston, R.J.; Zweben, S.J.

    1990-10-01

    The fraction of fusion-reaction energy that is released in energetic charged ions, such as the alpha particles of the D-T reaction, can be thermalized within the reacting plasma and used to maintain its temperature. This mechanism facilitates the achievement of very high energy-multiplication factors Q, but also raises a number of new issues of confinement physics. To ensure satisfactory reaction operation, three areas of energetic-ion interaction need to be addressed: single-ion transport in imperfectly symmetric magnetic fields or turbulent background plasmas; energetic-ion-driven (or stabilized) collective phenomena; and fusion-heat-driven collective phenomena. The first of these topics is already being explored in a number of tokamak experiments, and the second will begin to be addressed in the D-T-burning phase of TFTR and JET. Exploration of the third topic calls for high-Q operation, which is a goal of proposed next-generation plasma-burning projects. Planning for future experiments must take into consideration the full range of plasma-physics and engineering R ampersand D areas that need to be addressed on the way to a fusion power demonstration

  9. Lean and psychosocial work environment in manufacturing

    DEFF Research Database (Denmark)

    Edwards, Kasper; Thye, Nina; Nielsen, Anders P.

    2011-01-01

    Lean is currently the rationalization method of choice in the Danish manufacturing industry. This paper reports finding from three lean implementation cases. All cases are manufacturing companies focusing on upmarket products produced in small series. Prior to lean production was organized as sel...

  10. Lean - set i et historisk perspektiv

    DEFF Research Database (Denmark)

    Michelsen, Aage U

    2006-01-01

    I kapitlet redegøres for, hvordan begrebet Lean opstod som en karakteristik af Toyota Production System (TPS), der igen har sin rod i scientific management. Gennem eksempler illustreres det, at centrale Lean-principper således har været anvendt i årtier. Der argumenteres for, at Lean i mange...

  11. Lean Six Sigma in financial services

    NARCIS (Netherlands)

    de Koning, H.; Does, R.J.M.M.; Bisgaard, S.

    2008-01-01

    Lean Thinking and Six Sigma are typically considered as separate approaches to process innovation, with complementary strengths. When combined as Lean Six Sigma, this approach provides a unified framework for systematically developing innovations. Lean Six Sigma can also bring about significant

  12. System and method for treatment of a flue gas

    Science.gov (United States)

    Spiry, Irina Pavlovna; Wood, Benjamin Rue; Singh, Surinder Prabhjot; Perry, Robert James; McDermott, John Brian

    2017-09-19

    A method for treatment of a flue gas involves feeding the flue gas and a lean solvent to an absorber. The method further involves reacting the flue gas with the lean solvent within the absorber to generate a clean flue gas and a rich solvent. The method also involves feeding the clean flue gas from the absorber and water from a source, to a wash tower to separate a stripped portion of the lean solvent from the clean flue gas to generate a washed clean flue gas and a mixture of the water and the stripped portion of the lean solvent. The method further involves treating at least a portion of the mixture of the water and the stripped portion of the lean solvent via a separation system to separate the water from the stripped portion of the lean solvent.

  13. Change management in lean enterprise

    Directory of Open Access Journals (Sweden)

    Furman Joanna

    2016-06-01

    Full Text Available The main purpose of the paper is the analysis of a process of change focusing particularly on the concept of slimmed production (Lean and its implementation in the enterprise. A case study method was chosen as a research tool because it offers wide array of techniques and means of gaining and analysing data.

  14. Analysis Of Lean Accounting JIT And Balance Scorecard In The Companys Lean Manufacturing

    OpenAIRE

    Irwan Sutirman Wahdiat

    2015-01-01

    This research purpose to analyze the concept of Lean Manufacturing which is influenced by the role of JIT. This research uses a theoretical approach. This study portrait thinking companies that have yet to implement lean manufacturing and after doing the concept of lean manufacturing. This study shows that the concept of lean manufacturing can make the company more efficient and effective. This paper shows some lean manufacturing dimensions of the researchers previous researchers. This study ...

  15. Comparative Analysis between Lean, Six Sigma and Lean Six Sigma Concepts

    OpenAIRE

    Alexandra Mirela Cristina MUNTEANU

    2017-01-01

    This paper analyzes the benefits of Lean Six Sigma in comparison with Lean and Six Sigma, traditional improvement methodologies. The introduction highlights the appearance of Lean Six Sigma, early 2000s, as well as the benefits brought by the integrated approach. The following parts of the study emphasize the main differences between methodologies and their commonalities based on their synergy. Finally the advantages of Lean Six Sigma versus Lean and Six Sigma are analyzed and systematized by...

  16. Burning Mouth Syndrome

    Science.gov (United States)

    ... Care Home Health Info Health Topics Burning Mouth Burning Mouth Syndrome (BMS) is a painful, complex condition often described ... or other symptoms. Read More Publications Cover image Burning Mouth Syndrome Publication files Download Language English PDF — Number of ...

  17. Device for the catalytic after-burning of exhaust gases in the exhaust gas system of an internal-combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Lange, K

    1975-06-19

    The invention deals with a device which protects the catalyst for the after-burning of exhaust gases against damage by high temperatures. When the catalyst temperature reaches a certain limiting value, a throttle is activated by an electrical control device influenced by a temperature sensor via a servomotor. The throttle valve opens a by-pass for the exhaust gases which had previously flowed through the system for catalytic after-burning. In order to prevent the throttle from rusting due to its rare use, it is regularly put into use after switching off the ignition of the internal-combustion engine by the still briefly present oil pressure in the engine via an oil pressure switch and the mentioned control device.

  18. Exploiting HRM in support of lean manufacturing

    DEFF Research Database (Denmark)

    Jørgensen, Frances; Matthiesen, Rikke

    The purpose of this paper is to investigate the ways in HRM practices are-and could potentially be-exploited to support lean manufacturing in practice. First, a review of the pertinent literature regarding HRM, SHRM, and lean manufacturing is presented to provide an understanding of the mechanisms...... by which HRM practices could, theoretically, be used to support a lean implementation. Data presented in the paper are derived from 1) a longitudinal case study on lean implementation and 2) from managers currently involved with lean manufacturing in a second company. The relevant literature and the data...... depicting the potential role in supporting HRM/lean integrated practices. The analysis of the model with respect to the theoretical background emphasizes a number of areas in which HRM could be more fully exploited in order to more successfully support lean implementation, for example, by stressing HRM...

  19. Lean manufacturing in Indian context: A survey

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar

    2015-04-01

    Full Text Available This paper is an attempt to examine the implementation of Lean Manufacturing system in the Indian industries. Predominant elements of Lean Manufacturing, benefits gained after its implementation and obstacles observed by Indian Industry have been recognized. The results of this survey support the opinion that Lean Manufacturing had potential to improve the organizational performance of Indian industries. Nevertheless, Indian industries are required to be passionate to transform their manufacturing by adopting Lean manufacturing to gain the full benefits. A large numbers of literature papers are available on the better side of Lean manufacturing approach and its benefits gained by manufacturing organizations after implementation. But the adverse impacts of Lean manufacturing are not discussed to a great extent. Some drawbacks of Lean manufacturing are also highlighted in this paper.

  20. Lean Production Applications in a Manufacturing Company

    Directory of Open Access Journals (Sweden)

    Ali Görener

    2016-01-01

    Full Text Available Lean production is a production model which comes about the pursuit of companies to be able to meet competition and make effective production. The main purpose of lean production is to get control about the wastage. This study includes the requirements for the success of the lean production and how the lean production system can be established. In this paper, lean production techniques were applied to the electric water heater line. Measurements using lean initiatives were made, operation cycle times were determined, and Kaizen improvement methods and line balancing methods were applied according to the results. And the last section of study showed conclusion of lean implementation.

  1. Burning Mouth Syndrome and "Burning Mouth Syndrome".

    Science.gov (United States)

    Rifkind, Jacob Bernard

    2016-03-01

    Burning mouth syndrome is distressing to both the patient and practitioner unable to determine the cause of the patient's symptoms. Burning mouth syndrome is a diagnosis of exclusion, which is used only after nutritional deficiencies, mucosal disease, fungal infections, hormonal disturbances and contact stomatitis have been ruled out. This article will explore the many causes and treatment of patients who present with a chief complaint of "my mouth burns," including symptomatic treatment for those with burning mouth syndrome.

  2. Gas

    International Nuclear Information System (INIS)

    1996-01-01

    The French government has decided to modify the conditions of extension of local natural gas authorities to neighbouring districts. The European Union is studying the conditions of internal gas market with the objective of more open markets although considering public service requirements

  3. Slag processing system for direct coal-fired gas turbines

    Science.gov (United States)

    Pillsbury, Paul W.

    1990-01-01

    Direct coal-fired gas turbine systems and methods for their operation are provided by this invention. The gas turbine system includes a primary zone for burning coal in the presence of compressed air to produce hot combustion gases and debris, such as molten slag. The turbine system further includes a secondary combustion zone for the lean combustion of the hot combustion gases. The operation of the system is improved by the addition of a cyclone separator for removing debris from the hot combustion gases. The cyclone separator is disposed between the primary and secondary combustion zones and is in pressurized communication with these zones. In a novel aspect of the invention, the cyclone separator includes an integrally disposed impact separator for at least separating a portion of the molten slag from the hot combustion gases.

  4. Fundamental Study of a Single Point Lean Direct Injector. Part I: Effect of Air Swirler Angle and Injector Tip Location on Spray Characteristics

    Science.gov (United States)

    Tedder, Sarah A.; Hicks, Yolanda R.; Tacina, Kathleen M.; Anderson, Robert C.

    2015-01-01

    Lean direct injection (LDI) is a combustion concept to reduce oxides of nitrogen (NOx) for next generation aircraft gas turbine engines. These newer engines have cycles that increase fuel efficiency through increased operating pressures, which increase combustor inlet temperatures. NOx formation rates increase with higher temperatures; the LDI strategy avoids high temperature by staying fuel lean and away from stoichiometric burning. Thus, LDI relies on rapid and uniform fuel/air mixing. To understand this mixing process, a series of fundamental experiments are underway in the Combustion and Dynamics Facility at NASA Glenn Research Center. This first set of experiments examines cold flow (non-combusting) mixing using air and water. Using laser diagnostics, the effects of air swirler angle and injector tip location on the spray distribution, recirculation zone, and droplet size distribution are examined. Of the three swirler angles examined, 60 degrees is determined to have the most even spray distribution. The injector tip location primarily shifts the flow without changing the structure, unless the flow includes a recirculation zone. When a recirculation zone is present, minimum axial velocity decreases as the injector tip moves downstream towards the venturi exit; also the droplets become more uniform in size and angular distribution.

  5. Predictors of muscle protein synthesis after severe pediatric burns.

    Science.gov (United States)

    Diaz, Eva C; Herndon, David N; Lee, Jinhyung; Porter, Craig; Cotter, Matthew; Suman, Oscar E; Sidossis, Labros S; Børsheim, Elisabet

    2015-04-01

    Following a major burn, skeletal muscle protein synthesis rate increases but is often insufficient to compensate for massively elevated muscle protein breakdown rates. Given the long-term nature of the pathophysiologic response to burn injury, we hypothesized that muscle protein synthesis rate would be chronically elevated in severely burned children. The objectives of this study were to characterize muscle protein synthesis rate of burned children over a period of 24 months after injury and to identify predictors that influence this response. A total of 87 children with 40% or greater total body surface area (TBSA) burned were included. Patients participated in stable isotope infusion studies at 1, 2, and approximately 4 weeks after burn and at 6, 12, and 24 months after injury to determine skeletal muscle protein fractional synthesis rate. Generalized estimating equations with log link normal distribution were applied to account for clustering of patients and control for patient characteristics. Patients (8 ± 6 years) had large (62, 51-72% TBSA) and deep (47% ± 21% TBSA third degree) burns. Muscle protein fractional synthesis rate was elevated throughout the first 12 months after burn compared with established values from healthy young adults. Muscle protein fractional synthesis rate was lower in boys, in children older than 3 years, and when burns were greater than 80% TBSA. Muscle protein synthesis is elevated for at least 1 year after injury, suggesting that greater muscle protein turnover is a component of the long-term pathophysiologic response to burn trauma. Muscle protein synthesis is highly affected by sex, age, and burn size in severely burned children. These findings may explain the divergence in net protein balance and lean body mass in different populations of burn patients. Prognostic study, level III.

  6. Leaning in to "muddy" interviews

    DEFF Research Database (Denmark)

    Lippke, Lena; Tanggaard, Lene

    2014-01-01

    Over the last few decades, qualitative research has been acknowledged as a peopled practice in which subjectivities come into play. The main argument presented in this article is that qualitative research involves “muddy,” troublesome, interactional passages, because of a complex interplay between...... situated identities among the participants cross each other. We emphasize the value of daring to lean in to the muddiness of peopled research, use it as an analytical tool and present it in its imperfect form. This approach contributes to transparency in qualitative research, opens up the data in a new way...... subjectivities, situated identities, emotions, and conversational genres. Based on ethnographic fieldwork at a Danish Vocational Educational Training College, we introduce the concept of “leaning in” to provide an analytical grasp of the “muddy” interactional tension field in an interview situation, in which...

  7. Lean six sigma in healthcare.

    Science.gov (United States)

    de Koning, Henk; Verver, John P S; van den Heuvel, Jaap; Bisgaard, Soren; Does, Ronald J M M

    2006-01-01

    Healthcare, as with any other service operation, requires systematic innovation efforts to remain competitive, cost efficient, and up-to-date. This article outlines a methodology and presents examples to illustrate how principles of Lean Thinking and Six Sigma can be combined to provide an effective framework for producing systematic innovation efforts in healthcare. Controlling healthcare cost increases, improving quality, and providing better healthcare are some of the benefits of this approach.

  8. Comparative Analysis between Lean, Six Sigma and Lean Six Sigma Concepts

    Directory of Open Access Journals (Sweden)

    Alexandra Mirela Cristina MUNTEANU

    2017-06-01

    Full Text Available This paper analyzes the benefits of Lean Six Sigma in comparison with Lean and Six Sigma, traditional improvement methodologies. The introduction highlights the appearance of Lean Six Sigma, early 2000s, as well as the benefits brought by the integrated approach. The following parts of the study emphasize the main differences between methodologies and their commonalities based on their synergy. Finally the advantages of Lean Six Sigma versus Lean and Six Sigma are analyzed and systematized by author in order to reveal Lean Six Sigma’s benefits.

  9. The maintenance management for lean organization

    Directory of Open Access Journals (Sweden)

    Daniel D. GEORGESCU

    2010-12-01

    Full Text Available The goal of lean maintenance approach is to maintain organization international competitiveness. In the spirit of continuously improvement, in the paper it is shown how by adjusting some Lean manufacturing specific techniques for Total Productive Maintenance (TPM system, was born new maintenance system named Lean TPM. This is a systemic approach with three techniques, which don’t exclude specific techniques of TPM pillars, but complete them: the 7Ss as a critical first step in any improvement program; instantaneous maintenance; improvement setup operations. In the spirit of Lean principle, Lean TPM adjusts overall equipment effectiveness concept for all supply-chain from supplier to customer. Maintaining equipment in its optimal state and continually improving its productivity is the whole strategy behind Lean TPM.

  10. Cultural Aspects when Implementing Lean Production and Lean Product Development – Experiences from a Swedish Perspective

    Directory of Open Access Journals (Sweden)

    Promporn Wangwacharakul

    2014-07-01

    Full Text Available Lean principles and methods, originating in a Japanese cultural context, have spread to a large number of companies throughout the world. The aim of this case study research is to identify and compare national cultural aspects that influence Lean Production and Lean Product Development implementation in Swedish companies. Data were collected through questionnaires, interviews and an industrial workshop with Swedish Lean practitioners. The study shows that some sub-areas in Lean, such as value definition, control systems, leadership, team development, knowledge management, and strategies, are highly dependent on contextual factors related to human, cultural and organizational aspects. These are related to the national culture and should be considered to a higher extent for successful sustainable implementation of Lean in different cultural contexts. As for implementing Lean in Sweden, national cultural characteristics, such as individualism, autonomy and supportive management style fit well with Lean thinking.

  11. Lean Construction Supply Chain : A Literature Review

    OpenAIRE

    Ren, Jiamei

    2012-01-01

    The aim of this thesis is to enhance the management of supply systems in construction industry using lean principles. This study is an attempt to identify what kind of activities causes’ construction process delay and how to perform lean concept into supply chain in practice. The objective is to assure on-time delivery of information and materials to construction sites at lowest cost and maximum value for the customer. These study problems have been analysed from a lean construction supply ch...

  12. The maintenance management for lean organization

    OpenAIRE

    Daniel D. GEORGESCU

    2010-01-01

    The goal of lean maintenance approach is to maintain organization international competitiveness. In the spirit of continuously improvement, in the paper it is shown how by adjusting some Lean manufacturing specific techniques for Total Productive Maintenance (TPM) system, was born new maintenance system named Lean TPM. This is a systemic approach with three techniques, which don’t exclude specific techniques of TPM pillars, but complete them: the 7Ss as a critical first step in any improvemen...

  13. Apply Lean Thinking in Project Management

    OpenAIRE

    Pham Ngoc, Lan

    2015-01-01

    The purpose of this thesis was to study the effects of Lean Thinking in Project Management and how applying Lean Project Management could enhance the productivity of project work. The study was carried using theoretical research and collecting empirical data from three interviews and one case study at a local company. At the end of the study, the major project management problems at the company were identified and analyzed following Lean Principles. It was also pointed out where there...

  14. Lean Six Sigma in financial services

    OpenAIRE

    de Koning, H.; Does, R.J.M.M.; Bisgaard, S.

    2008-01-01

    Lean Thinking and Six Sigma are typically considered as separate approaches to process innovation, with complementary strengths. When combined as Lean Six Sigma, this approach provides a unified framework for systematically developing innovations. Lean Six Sigma can also bring about significant results and breakthrough improvements in financial services, as demonstrated with four case studies from Dutch multinational insurance companies. These cases demonstrate the importance of incremental i...

  15. Método basado en teledetección para estimar la emisión de gases efecto invernadero por quema de biomasa A remote sensing method to estimate greenhouse gas emissions from biomass burning

    Directory of Open Access Journals (Sweden)

    Jesús Adolfo Anaya Acevedo

    2011-01-01

    Full Text Available La quema de biomasa es una fuente importante de gases efecto invernadero en países en vías de desarrollo. En Colombia, el cambio de uso del suelo, la silvicultura y el sector agropecuario superan el 50% de las emisiones totales de efecto invernadero. El fuego se utiliza con frecuencia como un mecanismo para cambiar el uso del suelo. Los Llanos orientales y la Amazonía colombiana están sometidos todos los años a la quema de biomasa, especialmente entre enero y marzo. Los estudios en la distribución espacial y temporal de las emisiones son importantes de cara a los informes en el ámbito nacional. Este artículo de revisión describe el método para hacer estas estimaciones utilizando teledetección y algunos de los resultados disponibles para Colombia.Biomass burning is a major source of greenhouse gas emissions in developing countries. In Colombia, land use change, forestry and agriculture are responsible for more than 50% of the total greenhouse gas emissions. Fire is commonly used as a mechanism for land use change. In Colombia the Llanos Orientales and the Amazonia are subject to biomass burning every year during the dry season, especially from January to March. Studies of the spatial and temporal distribution of emissions are required for emissions report at a national level. The goal of this state of the art article is to describe a method to estimate emissions with a remote sensing approach and to present some of the variables already measured in Colombia.

  16. Methane Emissions from Leak and Loss Audits of Natural Gas Compressor Stations and Storage Facilities.

    Science.gov (United States)

    Johnson, Derek R; Covington, April N; Clark, Nigel N

    2015-07-07

    As part of the Environmental Defense Fund's Barnett Coordinated Campaign, researchers completed leak and loss audits for methane emissions at three natural gas compressor stations and two natural gas storage facilities. Researchers employed microdilution high-volume sampling systems in conjunction with in situ methane analyzers, bag samples, and Fourier transform infrared analyzers for emissions rate quantification. All sites had a combined total methane emissions rate of 94.2 kg/h, yet only 12% of the emissions total resulted from leaks. Methane slip from exhausts represented 44% of the total emissions. Remaining methane emissions were attributed to losses from pneumatic actuators and controls, engine crankcases, compressor packing vents, wet seal vents, and slop tanks. Measured values were compared with those reported in literature. Exhaust methane emissions were lower than emissions factor estimates for engine exhausts, but when combined with crankcase emissions, measured values were 11.4% lower than predicted by AP-42 as applicable to emissions factors for four-stroke, lean-burn engines. Average measured wet seal emissions were 3.5 times higher than GRI values but 14 times lower than those reported by Allen et al. Reciprocating compressor packing vent emissions were 39 times higher than values reported by GRI, but about half of values reported by Allen et al. Though the data set was small, researchers have suggested a method to estimate site-wide emissions factors for those powered by four-stroke, lean-burn engines based on fuel consumption and site throughput.

  17. Lean and the quality of work

    DEFF Research Database (Denmark)

    Jensen, Per Langaa

    2008-01-01

    Lean has for the last decade developed as the dominating model for developing productions processes not only within industry but also in health care, administration and service industries in general. With this development a discussion on human factors aspects of lean has developed internationally....... Literature studies documents that it is not possible to establish a clear relation between lean and the psychosocial aspects of work. The studies also indicate that the context and the implementations process play a dominating role in how lean is experienced. This has been the basis for establishing...

  18. Lean education an overview of current issues

    CERN Document Server

    Flumerfelt, Shannon; Kahlen, Franz-Josef

    2017-01-01

    This edited volume presents a structured approach to a new lean education curriculum, implemented for the education of engineers, managers, administrators as well as human resources developers. The authorship comprises professors and lecturers, trainers and practitioners who educate future professionals in Lean Thinking principles and tools. This edited book provides a platform for authors to share their efforts in building a Body of Knowledge (BoK) for Lean Education. The topical spectrum is state-of-the-art in this field, but the book also includes a glimpse into future developments. This is a highly informative and carefully presented book, providing valuable insight for scholars with an interest in Lean Education.

  19. A Methodology for the Assessment of Experiential Learning Lean: The Lean Experience Factory Study

    Science.gov (United States)

    De Zan, Giovanni; De Toni, Alberto Felice; Fornasier, Andrea; Battistella, Cinzia

    2015-01-01

    Purpose: The purpose of this paper is to present a methodology to assess the experiential learning processes of learning lean in an innovative learning environment: the lean model factories. Design/methodology/approach: A literature review on learning and lean management literatures was carried out to design the methodology. Then, a case study…

  20. Lean programm as a method of managing lean changes in the company

    Directory of Open Access Journals (Sweden)

    Suetina Tatiana Aleksandrovna

    2012-12-01

    Full Text Available This article is about methods and ways of providing changes on enterprices which introduce instruments of lean production. The main accent is how to use metodology of the project management by providing lean-changes. Lean program is proposed as a program of strategic developement of enterprices.

  1. Lean and Green Hand Surgery.

    Science.gov (United States)

    Van Demark, Robert E; Smith, Vanessa J S; Fiegen, Anthony

    2018-02-01

    Health care in the United States is both expensive and wasteful. The cost of health care in the United States continues to increase every year. Health care spending for 2016 is estimated at $3.35 trillion. Per capita spending ($10,345 per person) is more than twice the average of other developed countries. The United States also leads the world in solid waste production (624,700 metric tons of waste in 2011). The health care industry is second only to the food industry in annual waste production. Each year, health care facilities in the United States produce 4 billion pounds of waste (660 tons per day), with as much as 70%, or around 2.8 billion pounds, produced directly by operating rooms. Waste disposal also accounts for up to 20% of a hospital's annual environmental services budget. Since 1992, waste production by hospitals has increased annually by a rate of at least 15%, due in part to the increased usage of disposables. Reduction in operating room waste would decrease both health care costs and potential environmental hazards. In 2015, the American Association for Hand Surgery along with the American Society for Surgery of the Hand, American Society for Peripheral Nerve Surgery, and the American Society of Reconstructive Microsurgery began the "Lean and Green" surgery project to reduce the amount of waste generated by hand surgery. We recently began our own "Lean and Green" project in our institution. Using "minor field sterility" surgical principles and Wide Awake Local Anesthesia No Tourniquet (WALANT), both surgical costs and surgical waste were decreased while maintaining patient safety and satisfaction. As the current reimbursement model changes from quantity to quality, "Lean and Green" surgery will play a role in the future health care system. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  2. Lean production of intensive cities

    DEFF Research Database (Denmark)

    Ratner, Helene Gad; Bojesen, Anders; Bramming, Pia

    2014-01-01

    turnover. This is analysed in terms of Italo Calvino's Invisible cities. It is argued that Calvino's themes and prose help us understand change as a multiplicity of temporal intensities producing ambivalence and affect. We describe this use of literary abstractions as a ‘hyperbolic social epistemology......’. Through the depiction of four intensifications of Lean Production, the metaphors of Calvino's cities show how reality and illusion; hope and poverty; dreams and death and utopia and dystopia are intricately mingled and produce temporary and equally ambivalent affects of alienation, hypocrisy, self...

  3. Community energy plan : village of Burns Lake

    International Nuclear Information System (INIS)

    Rivard, B.

    2008-09-01

    Climate change has a significant impact on the lives of Canadians and their economies. In northern British Columbia, the ability to grow, process and transport food will likely change. The rising cost of fuel and other natural resources will create a need for more resilient communities. This report presented a community energy plan for Burns Lake in order to provide the first steps toward building on an already resilient community. The report answered questions about Burns Lake's energy consumption and greenhouse gas (GHG) emissions as well as the community's views on energy issues. The report provided background information on the Village of Burns Lake and discussed climate change in Burns Lake, energy use, and greenhouse gas emissions. The report also described community engagement by way of a questionnaire on fuel prices, homes and public opinion in Burns Lake. A strategy was also outlined. It was concluded that the village of Burns Lake is well positioned to face challenges regarding future energy use. The community is looking to the municipality for support and leadership, in order to deliver through active opportunities to reduce greenhouse gas emissions. 6 figs., 4 appendices.

  4. The LEAN Payload Integration Process

    Science.gov (United States)

    Jordan, Lee P.; Young, Yancy; Rice, Amanda

    2011-01-01

    It is recognized that payload development and integration with the International Space Station (ISS) can be complex. This streamlined integration approach is a first step toward simplifying payload integration; making it easier to fly payloads on ISS, thereby increasing feasibility and interest for more research and commercial organizations to sponsor ISS payloads and take advantage of the ISS as a National Laboratory asset. The streamlined integration approach was addressed from the perspective of highly likely initial payload types to evolve from the National Lab Pathfinder program. Payloads to be accommodated by the Expedite the Processing of Experiments for Space Station (EXPRESS) Racks and Microgravity Sciences Glovebox (MSG) pressurized facilities have been addressed. It is hoped that the streamlined principles applied to these types of payloads will be analyzed and implemented in the future for other host facilities as well as unpressurized payloads to be accommodated by the EXPRESS Logistics Carrier (ELC). Further, a payload does not have to be classified as a National Lab payload in order to be processed according to the lean payload integration process; any payload that meets certain criteria can follow the lean payload integration process.

  5. Effect of increased fuel temperature on emissions of oxides of nitrogen from a gas turbine combustor burning ASTM jet-A fuel

    Science.gov (United States)

    Marchionna, N. R.

    1974-01-01

    An annular gas turbine combustor was tested with heated ASTM Jet-A fuel to determine the effect of increased fuel temperature on the formation of oxides of nitrogen. Fuel temperature ranged from ambient to 700 K. The NOx emission index increased at a rate of 6 percent per 100 K increase in fuel temperature.

  6. Lean production and business performance: influences of ...

    African Journals Online (AJOL)

    Hence, this study aims to examine the influence of leadership style in the implementation of lean production. Data were gathered from randomly selected Malaysian manufacturing firms. Findings reveal a positive relationship between lean production and business performance. Specifically, democratic leadership style was ...

  7. Just-in-Time og Lean Manufacturing

    DEFF Research Database (Denmark)

    Michelsen, Aage U.

    2004-01-01

    Filosofi, principper og teknikker i JIT. Princip i Kanban-styring og dimensionering af et Kanban-system. Lean Thinking og Value Stream Mapping.......Filosofi, principper og teknikker i JIT. Princip i Kanban-styring og dimensionering af et Kanban-system. Lean Thinking og Value Stream Mapping....

  8. Indførelse af Lean principper

    DEFF Research Database (Denmark)

    Balmer, Christian; Michelsen, Aage U

    2004-01-01

    I artiklen beskrives, hvorledes lean-principper er indført i en forsikringsvirksomhed samt de opnåede resultater.......I artiklen beskrives, hvorledes lean-principper er indført i en forsikringsvirksomhed samt de opnåede resultater....

  9. Principles of lean planning and control

    NARCIS (Netherlands)

    Riezebos, J.

    2015-01-01

    Lean production systems use teams instead of functional departments as well as simple shop floor control methods to manage the flow of orders at the shop floor. Lean shop floor control focuses on robust and visual methods that are able to cope with variation in processing times, routing sequences,

  10. De praktijk van Lean Six Sigma

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Koning, H.

    2008-01-01

    Zowel Lean als Six Sigma zijn benaderingen van kwaliteits- en efficiëntieverbetering die op dit moment sterk in de belangstelling staan van zowel de industrie als de dienstverlening. Lean Six Sigma integreert beide benaderingen. Ze wordt door sommigen gezien als panacee voor alle mogelijke

  11. Disturbing Practices: Training Workers to Be Lean

    Science.gov (United States)

    Yasukawa, Keiko; Brown, Tony; Black, Stephen

    2014-01-01

    Purpose: The purpose of this paper is to explore the possibilities for expansive learning during organisational change. It considers the introduction of "lean production" as a disturbance to the existing work practices. Design/methodology/approach: The paper considers two case studies of "lean production" training with…

  12. Advancing lean manufacturing, the role of IT

    NARCIS (Netherlands)

    Riezebos, J.; Klingenberg, W.

    This introduction to the special issue discusses the changing role of information technology (IT) in advancing lean production. Lean principles and techniques have been applied in a wide variety of organisations, from make-to-stock to engineer-to-order industries, and even in typical service

  13. Lean in healthcare from employees' perspectives.

    Science.gov (United States)

    Drotz, Erik; Poksinska, Bozena

    2014-01-01

    The purpose of this paper is to contribute toward a deeper understanding of the new roles, responsibilities, and job characteristics of employees in Lean healthcare organizations. The paper is based on three cases studies of healthcare organizations that are regarded as successful examples of Lean applications in the healthcare context. Data were collected by methods including interviews, observations, and document studies. The implementation of Lean in healthcare settings has had a great influence on the roles, responsibilities, and job characteristics of the employees. The focus has shifted from healthcare professionals, where clinical autonomy and professional skills have been the guarding principles of patient care, to process improvement and teamwork. Different job characteristics may make it difficult to implement certain Lean practices in healthcare. Teamwork and decentralization of authority are examples of Lean practices that could be considered countercultural because of the strong professional culture and uneven power distribution, with doctors as the dominant decision makers. Teamwork, value flow orientation, and company-wide involvement in CI were associated with positive effects on the organizations' working environment, staff development, and organizational performance. In order to succeed with Lean healthcare, it is important to understand and recognize the differences in job characteristics between Lean manufacturing and healthcare. This paper provides insights into how Lean implementation changes the roles, responsibilities, and job characteristics of healthcare staff and the challenges and implications that may follow from this.

  14. Lean Six Sigma in a hospital

    NARCIS (Netherlands)

    van den Heuvel, J.; Does, R.J.M.M.; de Koning, H.

    2006-01-01

    Abstract Hospitals today face major challenges. Patients demand quality of care to be improved continuously. Health insurance companies demand the lowest possible prices. Lean Six Sigma is a program that can help healthcare providers to achieve these (seemingly) conflicting goals. Lean Six Sigma is

  15. Skaber lean bedre arbejdsmiljø?

    DEFF Research Database (Denmark)

    Hansen, Nanette Juhler

    2007-01-01

    rationalization strategies, among others Lean, claim to improve working conditions. The aim of this thesis is to identify whether the application of Lean strategies leads to a reduction of the occupational health and safety problem repetitive work. Repetitive work is a problem created by the Taylorisation of work......, and therefore it is to be expected that a break with one or more of the Tayloristic principles can lead to a reduction of repetitive work. This thesis points out a number of areas within which Lean breaks with Tayloristic principles, whilst other principles are maintained. These breaks between Lean...... and Taylorism are also found in the study of the case company. By linking breaks with Taylorism with solutions for the reduction of repetitive work, I point out a number of openings in Lean that may lead to a reduction of repetitive work. By using the concept of openings I present the possibilities offered...

  16. THE LEAN AND SIX SIGMA SINERGY

    Directory of Open Access Journals (Sweden)

    Mirko Sokovic

    2008-12-01

    Full Text Available Many organizations, dealing with continuous improvement methods, have realized that Lean and Six Sigma methodologies complement each other. Lean manufacturing focuses on the remova l of waste so that all processes in the total system add value from the customers' perspectives. The main emphasis of Six Sigma is the application of statistical tools in a disciplined manner, which requires data-driven decision-making. The integration of Lean and Six Sigma provides a synergetic effect, a rapid process improvement strategy for attaining organizational goals. When separated, Lean manufacturing cannot bring a process under statistical control, and Six Sigma cannot dramatically improve cycle time or reduce invested capital. Together, synergistic qualities are created to maximize the potential for a process improvement. The paper deals with Lean and Six Sigma principles and approaches used in modern manufacturing for process improvements, and bring forward benefits that are gained when these two methodologies are integrated.

  17. Lean thinking for a maintenance process

    Directory of Open Access Journals (Sweden)

    Sherif Mostafa

    2015-01-01

    Full Text Available The maintenance process shares significant operating costs in an organisation. Lean thinking can be incorporated into maintenance activities through applying its principles and practices/tools. Lean maintenance (LM is a prerequisite for lean manufacturing systems. This research proposes a new structure for LM process based on a systematic literature review of a significant number of related articles that were published on LM. The process structure is designed based on the five lean principles to guide and support organisations to pursue maintenance excellence. This study establishes a scheme for LM tools that are structured into 2 level 4 bundles and 26 lean practices/tools and develops a House of Waste (HoW to demonstrate the association between maintenance wastes and the LM tools. With a successful accomplishment of the proposed scheme, the performance of a maintenance department can create more improvement opportunities over time to reach the maintenance excellence status.

  18. Researching Lean: Methodological implications of loose definitions

    DEFF Research Database (Denmark)

    Brännmark, Mikael; Langstrand, Jostein; Johansson, Stina

    2012-01-01

    practices seem to overlap with other popular management concepts, such as High Performance Work Systems, World Class Manufacturing and Total Quality Management. This confusion, combined with different methodological and theoretical traditions, has led to much debate and contradictory conclusions regarding...... Lean. The purpose of the paper is to illustrate some key methodological issues that need to be considered in future Lean research to allow increased understanding of Lean effects for different stakeholders, primarily meaning the customer, employer and employees. Design/methodology/approach – The paper...... on the case studies, we suggest that future investigations describe the Lean interventions in more detail. General descriptions or analogies, e.g. ‘learning organizations’, presumably increase the present confusion regarding Lean impact on different stakeholders. The case studies also illustrate...

  19. Transferring lean management infrastructure for increasing productivity

    Directory of Open Access Journals (Sweden)

    Ph.D.Daniel Georgescu

    2010-12-01

    Full Text Available These years, manufacturing function have been transferred rapidly and globally from matured countries to emerging countries. In this paper is about the critical elements for successful transfer of lean management among sites and countries. Based on this general descriptive analysis, current global transfer activity of Lean as well as its future direction is also described. According to the gradual progress of lean management transfer, necessity of its refinement/reinforcement is recognized and some research subjects are proposed for contributing further encouragement of its global activities. In this paper, based on this understanding, requisites for transfer of lean management are discussed through investigating global activity of Lean and specification of infrastructure enabling its smooth transfer is examined

  20. TRUNK LEAN DURING A SINGLE-LEG SQUAT IS ASSOCIATED WITH TRUNK LEAN DURING PITCHING.

    Science.gov (United States)

    Plummer, Hillary A; Oliver, Gretchen D; Powers, Christopher M; Michener, Lori A

    2018-02-01

    Impaired trunk motion during pitching may be a risk factor for upper extremity injuries. Specifically, increased forces about the shoulder and elbow have been observed in pitchers with excessive contralateral trunk lean during pitching. Because of the difficulty in identifying abnormal trunk motions during a high-speed task such as pitching, a clinical screening test is needed to identify pitchers who have impaired trunk motion during pitching. The purpose of this study was to determine the relationship between the degree of lateral trunk lean during the single-leg squat and amount of trunk lean during pitching and if trunk lean during pitching can be predicted from lean during the single-leg squat. Controlled Laboratory Study; Cross-sectional. Seventy-three young baseball pitchers (11.4 ± 1.7 years; 156.3 ± 11.9 cm; 50.5 ± 8.8 kg) participated. An electromagnetic tracking system was used to obtain trunk kinematic data during a single-leg squat task (lead leg) and at maximum shoulder external rotation of a fastball pitch. Pearson correlation coefficients for trunk lean during the single-leg squat and pitching were calculated. A linear regression analysis was performed to determine if trunk lean during pitching can be predicted from lean during the single-leg squat. There was a positive correlation between trunk lean during the single-leg squat and trunk lean during pitching (r = 0.53; plean during the single-leg squat predicted the amount of lateral trunk lean during pitching (R 2 = 0.28; p lean during an SLS and pitching. Trunk lean during the single-leg squat explained 28% of the variance in trunk lean during pitching. Diagnosis, level 3.

  1. Modelling Lean and Green Supply Chain

    Science.gov (United States)

    Duarte, Susana Carla Vieira Lino Medina

    The success of an organization depends on the effective control of its supply chain. It is important to recognize new opportunities for organization and its supply chain. In the last few years the approach to lean, agile, resilient and green supply chain paradigms has been addressed in the scientific literature. Research in this field shows that the integration of these concepts revealed some contradictions among so many paradigms. This thesis is mainly focused on the lean and green approaches. Thirteen different management frameworks, embodied in awards, standards and tools were studied to understand if they could contribute for the modelling process of a lean and green approach. The study reveals a number of categories that are common in most management frameworks, providing adequate conditions for a lean and green supply chain transformation. A conceptual framework for the evaluation of a lean and green organization`s supply chain was proposed. The framework considers six key criteria, namely, leadership, people, strategic planning, stakeholders, processes and results. It was proposed an assessment method considering a criteria score for each criterion. The purpose is to understand how lean and green supply chain can be compatible, using principles, practices, techniques or tools (i.e. elements) that support both, a lean and a green approach, in all key criteria. A case study in the automotive upstream supply chain was performed to understand more deeply if the elements proposed for the conceptual framework could be implemented in a real-scenario. Based on the conceptual framework and the case study, a roadmap to achieve a lean-green transformation is presented. The proposed roadmap revealed its contribution to the understanding on how and when an organization`s supply chain should apply the lean and green elements. This study is relevant to practice, as it may assist managers in the adoption of a lean and green supply chain approach, giving insights for the

  2. Optimization of burn referrals

    DEFF Research Database (Denmark)

    Reiband, Hanna K; Lundin, Kira; Alsbjørn, Bjarne

    2014-01-01

    INTRODUCTION: Correct estimation of the severity of burns is important to obtain the right treatment of the patient and to avoid over- and undertriage. In this study we aimed to assess how often the guidelines for referral of burn injured patients are met at the national burn centre (NBC), Denmar...

  3. Epidemiology of burns

    NARCIS (Netherlands)

    Dokter, Jan

    2016-01-01

    The aim of this thesis is to understand the epidemiology, treatment and outcomes of specialized burn care in The Netherlands. This thesis is mainly based on historical data of the burn centre in Rotterdam from 1986, combined with historical data from the burn centres in Groningen and Beverwijk from

  4. Investigation of low emission combustors using hydrogen lean direct injection

    Directory of Open Access Journals (Sweden)

    Robert ISAC

    2011-09-01

    Full Text Available One of the key technology challenges for the use of hydrogen in gas turbine engines is the performance of the combustion system, in particular the fuel injectors. Tests were conducted to measure the nitrogen oxide (NOx emissions and combustion performance at inlet conditions of 588 to 811 K, 0.4 to 1.4 MPa, and equivalence ratios up to 0.48. All the injectors were based on Lean Direct Injection (LDI technology with multiple injection points and quick mixing. One challenge to hydrogen-based premixing combustion systems is flashback since hydrogen has a reaction rate over 7 times that of Jet-A.

  5. Method of burning petrochemical products

    Energy Technology Data Exchange (ETDEWEB)

    Sado, I

    1973-01-12

    This invention concerns a method of burning wastes such as polyvinyl chloride or other synthetic resin products and rubbers, in which wastes are burned in a nearly smokeless and odorless state. The method is characterized by a process by which petrochemical waste products are subjected to a spontaneous combustion in a casserole state in a closed combustion room in such a way that no air is supplied whatever, and subsequently the gas so generated is sent successively in an adequate amount into a separately installed second combustion room where it is reburnt at a high temperature of more than 1000 C by a jet flame from the oil burners mounted inside the combustion room. Usually, petrochemical products emanate black smoke of Ringelmann concentration of more than five and a strong odor, but in this method, particularly in the case of polyvinyl chloride the exhaust smoke has a Ringelmann smoke concentration of less than one and is almost odorless because the plastic is completely gasified by the spontaneous combustion and completely burned at 1300 to 1400/sup 0/C with oil and air in the second combustion room. When the exhaust smoke is passed through a neutralization tank to remove the chloride compounds in the smoke, the damaging contribution of the exhaust gas or smoke to the secondary pollution can be completely eliminated.

  6. An empirical review of lean manufacturing and their strategies

    Directory of Open Access Journals (Sweden)

    Virender Chahal

    2017-07-01

    Full Text Available The theory of lean manufacturing provides the quality of the products in minimum cost and pro-vides customer satisfaction. Today, the competition level is very high and every industry tries to supply high quality products in nominal cost, so lean is the latest tool to achieve. The objective of this paper is to study different lean concepts under various lean strategies. This study helps to find out the status of lean manufacturing and its ways of implementation. Also in this paper, there is a discussion about lean manufacturing concept, lean waste, lean strategies, lean barriers and cycle of lean implementation. This paper presents a literature review to clear the status of lean manufacturing and their strategies with help of collection of relevant papers.

  7. One-step reduced kinetics for lean hydrogen-air deflagration

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Galisteo, D.; Sanchez, A.L. [Area de Mecanica de Fluidos, Univ. Carlos III de Madrid, Leganes 28911 (Spain); Linan, A. [ETSI Aeronauticos, Pl. Cardenal Cisneros 3, Madrid 28040 (Spain); Williams, F.A. [Dept. of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093-0411 (United States)

    2009-05-15

    A short mechanism consisting of seven elementary reactions, of which only three are reversible, is shown to provide good predictions of hydrogen-air lean-flame burning velocities. This mechanism is further simplified by noting that over a range of conditions of practical interest, near the lean flammability limit all reaction intermediaries have small concentrations in the important thin reaction zone that controls the hydrogen-air laminar burning velocity and therefore follow a steady state approximation, while the main species react according to the global irreversible reaction 2H{sub 2} + O{sub 2} {yields} 2H{sub 2}O. An explicit expression for the non-Arrhenius rate of this one-step overall reaction for hydrogen oxidation is derived from the seven-step detailed mechanism, for application near the flammability limit. The one-step results are used to calculate flammability limits and burning velocities of planar deflagrations. Furthermore, implications concerning radical profiles in the deflagration and reasons for the success of the approximations are clarified. It is also demonstrated that adding only two irreversible direct recombination steps to the seven-step mechanism accurately reproduces burning velocities of the full detailed mechanism for all equivalence ratios at normal atmospheric conditions and that an eight-step detailed mechanism, constructed from the seven-step mechanism by adding to it the fourth reversible shuffle reaction, improves predictions of O and OH profiles. The new reduced-chemistry descriptions can be useful for both analytical and computational studies of lean hydrogen-air flames, decreasing required computation times. (author)

  8. To burn or not to burn

    International Nuclear Information System (INIS)

    Busch, L.

    1993-01-01

    While taking a match to an oil slick may sound like the making of a chaotic inferno, emergency response specialists say burning may be the most efficient way to remove large oil spills from the ocean's surface. But tests of this technique are being resisted by environmentalists as well as the Environmental Protection Agency (EPA), which has final authority over the matter. The debate over test burning arose most recently in Alaska when a proposal to spill and then ignite 1,000 barrels of crude on the Arctic Ocean this past summer was rejected by the EPA. The EPA didn't object to the technique or to the notion of burning spilled oil. However, it contends that it's not necessary to spill thousands of gallons of oil to conduct tests, and unnecessarily pollute the environment, when plenty of oil is already available from accidental spills. Researchers disagree, claiming they won't be able to use the burning technique on an actual spill until it has been tested in a controlled experiment. Despite such concerns, the Canadian government is going ahead with a test burn off the coast of Newfoundland next year. Faced with a choice of test burning or the kind of shoreline contamination left in the wake of the Exxon Valdez disaster, Environment Canada opts for testing. Learning valuable lessons about rapid oil-spill cleanup is worth the relatively minor risks to the environment that test burning would pose

  9. Subfilter Scale Modelling for Large Eddy Simulation of Lean Hydrogen-Enriched Turbulent Premixed Combustion

    NARCIS (Netherlands)

    Hernandez Perez, F.E.

    2011-01-01

    Hydrogen (H2) enrichment of hydrocarbon fuels in lean premixed systems is desirable since it can lead to a progressive reduction in greenhouse-gas emissions, while paving the way towards pure hydrogen combustion. In recent decades, large-eddy simulation (LES) has emerged as a promising tool to

  10. Adapting lean to histology laboratories.

    Science.gov (United States)

    Buesa, René J

    2009-10-01

    Histology laboratories (histolabs) can increase productivity and reduce turnaround time and errors by using any one of several available management tools. After a few years of operation, all histolabs develop workflow problems. Histology laboratories handling more than 20,000 cases per year benefit the most from implementing management tools, as occurred in the 25 facilities summarized in this article. Discontinuous workflow, lack of "pulling" between steps, accepting unavoidable waiting times while working with small batches within work cells, and a workflow with an uneven rate of completion, are some of the adaptations required by the Lean system when it is used in histology because 70% of the tasks are manual and the flow has to be interrupted to add value to the pieces of tissue during tissue processing, no matter how short that step is. After all these adaptations are incorporated, the histolab becomes as "Lean" as it can be, and the qualifier is also a recognition of the effort and personnel involvement in the implementation. Given its service nature, productivity increments do not expand the histolab customer base and could lead to staffing reductions. This is one of the causes of reluctance by some employees for implementing these techniques which are mostly driven by cost reductions sought by insurance companies and administrators, and not necessarily because of a real medical need to reduce the turnaround time. Finally, any histolab wanting to improve its workflow can follow some easy steps presented here as a guide to accomplish that objective. These steps stress the need for the supervisors to insure that the personnel in the histology laboratory are being paid at a comparable rate as other histolabs in the area.

  11. Method for burning radioactive wastes

    International Nuclear Information System (INIS)

    Hattori, Akinori; Tejima, Takaya.

    1987-01-01

    Purpose: To completely process less combustible radioactive wastes with no excess loads on discharge gas processing systems and without causing corrosions to furnace walls. Method: Among combustible radioactive wastes, chlorine-containing less combustible wastes such as chlorine-containing rubbers and vinyl chlorides, and highly heat generating wastes not containing chloride such as polyethylene are selectively packed into packages. While on the other hand, packages of less combustible wastes are charged into a water-cooled jacket type incinerator intermittently while controlling the amount and the interval of charging so that the temperature in the furnace will be kept to lower than 850 deg C for burning treatment. Directly after the completion of the burning, the packed highly heat calorie producing wastes are charged and subjected to combustion treatment. (Yoshihara, H.)

  12. Lean Six Sigma implementation and organizational culture.

    Science.gov (United States)

    Knapp, Susan

    2015-01-01

    The purpose of this paper is to examine the relationship between four organizational cultural types defined by the Competing Values Framework and three Lean Six Sigma implementation components - management involvement, use of Lean Six Sigma methods and Lean Six Sigma infrastructure. The study involved surveying 446 human resource and quality managers from 223 hospitals located in Maine, New Hampshire, Vermont, Massachusetts and Rhode Island using the Organizational Culture Assessment Instrument. Findings - In total, 104 completed responses were received and analyzed using multivariate analysis of variance. Follow-up analysis of variances showed management support was significant, F(3, 100)=4.89, p cultures having significant interactions with management support. The relationship between organizational culture and Lean Six Sigma in hospitals provides information on how specific cultural characteristics impact the Lean Six Sigma initiative key components. This information assists hospital staff who are considering implementing quality initiatives by providing an understanding of what cultural values correspond to effective Lean Six Sigma implementation. Managers understanding the quality initiative cultural underpinnings, are attentive to the culture-shared values and norm's influence can utilize strategies to better implement Lean Six Sigma.

  13. Lean in healthcare: the unfilled promise?

    Science.gov (United States)

    Radnor, Zoe J; Holweg, Matthias; Waring, Justin

    2012-02-01

    In an effort to improve operational efficiency, healthcare services around the world have adopted process improvement methodologies from the manufacturing sector, such as Lean Production. In this paper we report on four multi-level case studies of the implementation of Lean in the English NHS. Our results show that this generally involves the application of specific Lean 'tools', such as 'kaizen blitz' and 'rapid improvement events', which tend to produce small-scale and localised productivity gains. Although this suggests that Lean might not currently deliver the efficiency improvements desired in policy, the evolution of Lean in the manufacturing sector also reveals this initial focus on the 'tool level'. In moving to a more system-wide approach, however, we identify significant contextual differences between healthcare and manufacturing that result in two critical breaches of the assumptions behind Lean. First, the customer and commissioner in the private sector are the one and the same, which is essential in determining 'customer value' that drives process improvement activities. Second, healthcare is predominantly designed to be capacity-led, and hence there is limited ability to influence demand or make full use of freed-up resources. What is different about this research is that these breaches can be regarded as not being primarily 'professional' in origin but actually more 'organisational' and 'managerial' and, if not addressed could severely constrain Lean's impact on healthcare productivity at the systems level. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. The human side of lean teams.

    Science.gov (United States)

    Wackerbarth, Sarah B; Strawser-Srinath, Jamie R; Conigliaro, Joseph C

    2015-05-01

    Organizations use lean principles to increase quality and decrease costs. Lean projects require an understanding of systems-wide processes and utilize interdisciplinary teams. Most lean tools are straightforward, and the biggest barrier to successful implementation is often development of the team aspect of the lean approach. The purpose of this article is to share challenges experienced by a lean team charged with improving a hospital discharge process. Reflection on the experience provides an opportunity to highlight lessons from The Team Handbook by Peter Scholtes and colleagues. To improve the likelihood that process improvement initiatives, including lean projects, will be successful, organizations should consider providing training in organizational change principles and team building. The authors' lean team learned these lessons the hard way. Despite the challenges, the team successfully implemented changes throughout the organization that have had a positive impact. Training to understand the psychology of change might have decreased the resistance faced in implementing these changes. © 2014 by the American College of Medical Quality.

  15. Leading Lean: a Canadian healthcare leader's guide.

    Science.gov (United States)

    Fine, Benjamin A; Golden, Brian; Hannam, Rosemary; Morra, Dante

    2009-01-01

    Canadian healthcare organizations are increasingly asked to do more with less, and too often this has resulted in demands on staff to simply work harder and longer. Lean methodologies, originating from Japanese industrial organizations and most notably Toyota, offer an alternative - tried and tested approaches to working smarter. Lean, with its systematic approaches to reducing waste, has found its way to Canadian healthcare organizations with promising results. This article reports on a study of five Canadian healthcare providers that have recently implemented Lean. We offer stories of success but also identify potential obstacles and ways by which they may be surmounted to provide better value for our healthcare investments.

  16. Laminar burning velocities of near-flammability-limit H{sub 2}-air-steam mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Loesel Sitar, J V; Chan, C K; Torchia, F; Guerrero, A

    1996-12-31

    Laminar burning velocities of lean H{sub 2}-air-steam mixtures near the flammability limit were measured by using the pressure-time history of an expanding flame kernel. Although flames in these mixtures are inherently unstable, this difficulty was avoided by using the early pressure rise of the burn. A comparison of results from that method with burning velocities determined from schlieren photographs of the expanding flame kernel gave good agreement. Despite the difficulties, it is believed that the pressure trace method gives results that are useful in modelling reactor accident scenarios. 8 refs., 4 figs.

  17. Laminar burning velocities of near-flammability-limit H2-air-steam mixtures

    International Nuclear Information System (INIS)

    Loesel Sitar, J.V.; Chan, C.K.; Torchia, F.; Guerrero, A.

    1995-01-01

    Laminar burning velocities of lean H 2 -air-steam mixtures near the flammability limit were measured by using the pressure-time history of an expanding flame kernel. Although flames in these mixtures are inherently unstable, this difficulty was avoided by using the early pressure rise of the burn. A comparison of results from that method with burning velocities determined from schlieren photographs of the expanding flame kernel gave good agreement. Despite the difficulties, it is believed that the pressure trace method gives results that are useful in modelling reactor accident scenarios. 8 refs., 4 figs

  18. A study on the amount of pilot injection and its effects on rich and lean boundaries of the premixed CNG/air mixture for a CNG/diesel dual-fuel engine

    Energy Technology Data Exchange (ETDEWEB)

    Zhiqiang Lin; Wanhua Su [Tianjin University (China). State Key Laboratory of Engines

    2003-07-01

    A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must be made richer, otherwise THC emissions would increase. However, the soot emissions remain almost unchanged at a very low level. (author)

  19. Making it lean applying lean practices to the work of it

    CERN Document Server

    Williams, Howard

    2013-01-01

    Making IT Lean: Applying Lean Practices to the Work of IT presents Lean concepts and techniques for improving processes and eliminating waste in IT operations and IT Service Management, in a manner that is easy to understand. The authors provide a context for discussing several areas of application within this domain, allowing you to quickly gain insight into IT processes and Lean principles.The text reviews IT Service Management, with reference to the IT Infrastructure Library (ITIL®) as a framework for best practices-explaining how to use it to accommod

  20. Which is the most efficient agent for the diffusion of a high-performance technology? Study of the gas-burning condensing boilers'market in four European countries

    International Nuclear Information System (INIS)

    Cauret, L.; Adnot, J.; Haug, J.; Weber, Ch.

    1999-01-01

    The diffusion of technology is often confronted to numerous barriers (market, economical, social...). The combination of strategies along the partners' chain - equipment manufacturer, utility, government, retailer, installer and customer - contributes to the success or the failure of a diffusion. For a given technology, the comparison of different national markets can help to understand why diffusion programs are successful in a country and not in another one. The gas-burning condensing boilers is a good example. It is theoretically the post efficient boiler with LHV efficiency above 100 %, which guarantee an attractive pay-back period for an individual unit (below 10 years) or for a collective equipment (below 5 years). It also induces lower CO 2 and NO x emissions. But the success on the market of this highly-efficient technology, designed in the seventies, has been dramatically different according to the country. The authors reconstitute these market evolutions for the four countries (France, Germany, Great Britain and Netherlands). Furthermore, the link between sales and strategy of main parties involved ( equipment maker, utility, government, retailer, installer and customer - is analysed throughout the past and current promoting methods implemented for their development (R and D supports by utility, subsidies to customers, subsidies to installers...). Finally, the authors prove the role of the involved partners' chain and of the management of subsidies as determining factors for any market development. (authors)

  1. Geographic patterns of carbon dioxide emissions from fossil-fuel burning, hydraulic cement production, and gas flaring on a one degree by one degree grid cell basis: 1950 to 1990

    Energy Technology Data Exchange (ETDEWEB)

    Brenkert, A.L. [ed.] [Oak Ridge National Lab., TN (United States). Carbon Dioxide Information Analysis Center; Andres, R.J. [Univ. of Alaska, Fairbanks, AK (United States). Inst. of Northern Engineering; Marland, G. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.; Fung, I. [Univ. of Victoria, British Columbia (Canada)]|[National Aeronautics and Space Administration, New York, NY (United States). Goddard Inst. for Space Studies; Matthews, E. [Columbia Univ., New York, NY (United States)]|[National Aeronautics and Space Administration, New York, NY (United States). Goddard Inst. for Space Studies

    1997-03-01

    Data sets of one degree latitude by one degree longitude carbon dioxide (CO{sub 2}) emissions in units of thousand metric tons of carbon (C) per year from anthropogenic sources have been produced for 1950, 1960, 1970, 1980 and 1990. Detailed geographic information on CO{sub 2} emissions can be critical in understanding the pattern of the atmospheric and biospheric response to these emissions. Global, regional and national annual estimates for 1950 through 1992 were published previously. Those national, annual CO{sub 2} emission estimates were based on statistics on fossil-fuel burning, cement manufacturing and gas flaring in oil fields as well as energy production, consumption and trade data, using the methods of Marland and Rotty. The national annual estimates were combined with gridded one-degree data on political units and 1984 human populations to create the new gridded CO{sub 2} emission data sets. The same population distribution was used for each of the years as proxy for the emission distribution within each country. The implied assumption for that procedure was that per capita energy use and fuel mix is uniform over a political unit. The consequence of this first-order procedure is that the spatial changes observed over time are solely due to changes in national energy consumption and nation-based fuel mix. Increases in emissions over time are apparent for most areas.

  2. LEAN SIX SIGMA – MULTIPLE CASE STUDY

    Directory of Open Access Journals (Sweden)

    Delvio Venanzi

    2017-12-01

    Full Text Available Lean Six Sigma é uma gestão focada na qualidade e desempenho produtivo em sistemas operacionais. Este artigo discute os fundamentos desta metodologia através de duas diferentes concepções de gestão, Lean Manufacturing e Six Sigma. Primeiro, o artigo explica o DMAIC (definir, medir, analisar, melhorar e controlar e suas respectivas fases, após a filosofia Lean com o sipoc e técnicas de mapeamento de fluxo de valor. O artigo pretende mostrar a integração destes dois conceitos e seus resultados. A metodologia consistiu em uma teoria baseada em uma pesquisa bibliográfica de pesquisa exploratória que consistiu de três estudos de caso em empresas de diferenças localizadas em Sorocaba, São Paulo. Neste artigo estuda a aplicação de Lean Seis Sigma e seus resultados.

  3. Lean Construction Applications for Bridge Inspection

    Science.gov (United States)

    2017-10-01

    Lean philosophy was used to analyze the efficiency of bridge inspection. Emphasis was put on identifying activities that add value to the final output, an owner approved bridge inspection report. 26 bridge inspections were shadowed. Time spent on bri...

  4. Lean in service industries: A literature review

    Science.gov (United States)

    V, Vignesh; Suresh, M.; Aramvalarthan, S.

    2016-09-01

    Lean service is an amalgamation of tools and practices which, if applied appropriately, would definitely improve the existing quality of operations and ensure the generation of a large amount of favourable financial and economic outcomes and improve the behaviour of the workforce. As a result, it assumes of great significance in the fiercely competitive modern world. This article presents a comprehensive bibliographic study about the various lean service practices through a variety of approaches like service improvement, manufacturing, supply chain, market and retailing approaches, etc. Thus it gives a clear view on how the lean services are implemented in various sectors and the contribution of lean service towards improving the quality in the services provided while reducing the costs.

  5. Implementation of Lean Manufacturing in Romanian Organisations

    Directory of Open Access Journals (Sweden)

    Ucenic Camelia Ioana

    2017-01-01

    Full Text Available The implementation of lean manufacturing is one of the main tools for attaining a higher performance level in the Romanian organisations. The study uses data collected at middle management level from organisations located in Transylvania. The organisations come from different fields of activity and are in different stages of lean implementation. The article makes use of quantitative and qualitative instruments for the evaluation of lean in the above mentioned companies. Characteristics as waste reduction, cost, quality, product design have different approaches in the companies. Their way of approach gives useful information regarding the type of company from the point of view of lean manufacturing implementation. This knowledge provides a useful support at different managerial levels in the process of decision making.

  6. Lean six sigma application to transportation logistics

    Directory of Open Access Journals (Sweden)

    Simone Tavares Fernandes

    2012-06-01

    Full Text Available This work presents the application of Lean Six Sigma in a case study of a metallurgic industry. The Six Sigma and the Lean are two processes used by enterprises in Brazil and worldwide. Currently the integration of these processes is a challenge for these companies, which search a way more efficient to reduce their wastes and to adapt to the needs of their markets. The paper had as purpose to demonstrate the applicability of the Lean Six Sigma in a real logistical problem related to the transportation of goods among units of a metallurgic industry. The stages used for the solution of the problem follow the DMAIC cycle – Define, Measure, Analyze, Improve and Control. The paper presents in details the integrated approach of the improvement processes Lean and Six Sigma, their tools set, as well the excellent results obtained in the case study.

  7. LEAN Tools in the IT Sector

    Directory of Open Access Journals (Sweden)

    Zoltan VAJNA

    2015-05-01

    Full Text Available Nowadays the LEAN tools with their proven efficiency are indispensable parts of the production management. I think there is no producing enterprise that cannot utilize a wide variety of these LEAN tools. The question now is how these tools can support companies in increasing the efficiency of their supporting IT processes. In this study I will demonstrate how these well-known LEAN tools from production management can be used in IT management to create more cost-effective, efficient and transparent solutions during the IT system development and IT operation activities. I will show respectively without attempting to be comprehensive the most important tools of the LEAN management and I will analyse how these tools can be used in the IT sector. At the end of this study I will demonstrate what the IT managers think about the practical use of these tools.

  8. A case study of lean, sustainable manufacturing

    Directory of Open Access Journals (Sweden)

    Geoff Miller

    2010-06-01

    Full Text Available A small furniture production company has integrated lean tools and sustainability concepts with discrete event simulation modeling and analysis as well as mathematical optimization to make a positive impact on the environment, society and its own financial success. The principles of lean manufacturing that aid in the elimination of waste have helped the company meet ever increasing customer demands while preserving valuable resources for future generations. The implementation of lean and sustainable manufacturing was aided by the use of discrete event simulation and optimization to overcome deficits in lean’s traditional implementation strategies. Lean and green manufacturing can have a more significant, positive impact on multiple measures of operational performance when implemented concurrently rather than separately. These ideas are demonstrated by three applications.

  9. A Web-Based Lean Simulation Game for Office Operations: Training the Other Side of a Lean Enterprise

    Science.gov (United States)

    Kuriger, Glenn W.; Wan, Huang-da; Mirehei, S. Moussa; Tamma, Saumya; Chen, F. Frank

    2010-01-01

    This research proposes a Web-based version of a lean office simulation game (WeBLOG). The game is designed to be used to train lean concepts to office and administrative personnel. This group belongs to the frequently forgotten side of a lean enterprise. Over four phases, the game presents the following seven lean tools: one-piece flow,…

  10. The Finnish healthcare services lean management.

    Science.gov (United States)

    Hihnala, Susanna; Kettunen, Lilja; Suhonen, Marjo; Tiirinki, Hanna

    2018-02-05

    Purpose The purpose of this paper is to discuss health services managers' experiences of management in a special health-care unit and development efforts from the point of view of the Lean method. Additionally, the aim is to deepen the knowledge of the managers' work and nature of the Lean method development processes in the workplace. The research focuses on those aspects and results of Lean method that are currently being used in health-care environments. Design/methodology/approach These data were collected through a number of thematic interviews. The participants were nurse managers ( n = 7) and medical managers ( n = 7) who applied Lean management in their work at the University Hospital in the Northern Ostrobothnia Health Care District. The data were analysed with a qualitative content analysis. Findings A common set of values in specialized health-care services, development of activities and challenges for management in the use of the Lean manager development model to improve personal management skills. Practical implications Managers in specialized health-care services can develop and systematically manage with the help of the Lean method. This emphasizes assumptions, from the point of view of management, about systems development when the organization uses the Lean method. The research outcomes originate from specialized health-care settings in Finland in which the Lean method and its associated management principles have been implemented and applied to the delivery of health care. Originality/value The study shows that the research results and in-depth knowledge on Lean method principles can be applied to health-care management and development processes. The research also describes health services managers' experiences of using the Lean method. In the future, these results can be used to improve Lean management skills, identify personal professional competencies and develop skills required in development processes. Also, the research findings can be used

  11. Effects of NOX Storage Component on Ammonia Formation in TWC for Passive SCR NOX Control in Lean Gasoline Engines

    Energy Technology Data Exchange (ETDEWEB)

    Prikhodko, Vitaly Y. [ORNL; Pihl, Josh A. [ORNL; Toops, Todd J. [ORNL; Parks, II, James E. [ORNL

    2018-04-01

    A prototype three-way catalyst (TWC) with NOX storage component was evaluated for ammonia (NH3) generation on a 2.0-liter BMW lean burn gasoline direct injection engine as a component in a passive ammonia selective catalytic reduction (SCR) system. The passive NH3 SCR system is a potential approach for controlling nitrogen oxides (NOX) emissions from lean burn gasoline engines. In this system, NH3 is generated over a close-coupled TWC during periodic slightly-rich engine operation and subsequently stored on an underfloor SCR catalyst. Upon switching to lean, NOX passes through the TWC and is reduced by the stored NH3 on the SCR catalyst. Adding a NOX storage component to a TWC provides two benefits in the context of a passive SCR system: (1) enabling longer lean operation by storing NOX upstream and preserving NH3 inventory on the downstream SCR catalyst; and (2) increasing the quantity and rate of NH3 production during rich operation. Since the fuel penalty associated with passive SCR NOX control depends on the fraction of time that the engine is running rich rather than lean, both benefits (longer lean times and shorter rich times achieved via improved NH3 production) will decrease the passive SCR fuel penalty. However, these benefits are primarily realized at low to moderate temperatures (300-500 °C), where the NOX storage component is able to store NOX, with little to no benefit at higher temperatures (>500 °C), where NOX storage is no longer effective. This study discusses engine parameters and control strategies affecting the NH3 generation over a TWC with NOX storage component.

  12. Lean Implementation : the significance of people and dualism

    OpenAIRE

    Bengt, Halling

    2013-01-01

    Lean, with its origins at the Toyota Motor Company, is a concept that is known to increase effectiveness in manufacturing. The Lean concept is now argued to be relevant not only in manufacturing but in service and health-care delivery as well. The reported results of Lean implementation efforts are divided. There are reports that most of the Lean implementation efforts are not reaching the goal; on the other hand, there are reports of promising results. The divided results from Lean implement...

  13. Lean in the supply chain : research and practice

    OpenAIRE

    Ugochukwu, Paschal

    2012-01-01

    Lean is a management philosophy that enhances customer value through waste elimination and continuous improvement in a system by applying lean principles, practices, and techniques. The focus on lean implementations and research had been typically a single company without extension to the entire supply chain. When the concept of lean is implemented across the entire supply chain, however, it is referred to as lean supply chain. The purpose of this thesis is to create a structure from theory a...

  14. Lean in healthcare: A comprehensive review.

    Science.gov (United States)

    D'Andreamatteo, Antonio; Ianni, Luca; Lega, Federico; Sargiacomo, Massimo

    2015-09-01

    Lean seems to be the next revolution for a better, improved, value-based healhcare. In the last 15 years Lean has been increasingly adapted and adopted in healthcare. Accordingly, Lean healthcare has been developing into a major strand of research since the early 2000s. The aim of this work is to present a comprehensive overview of the main issues highlighted by research on implementation of Lean in a complex contest such as the healthcare one. Comprehensive literature review was conducted in order to identify empirical and theoretical articles published up to September 2013. Thematic analysis was performed in order to extract and synthesis data. 243 articles were selected for analysis. Lean is best understood as a means to increase productivity. Hospital is the more explored setting, with emergency and surgery as the pioneer departments. USA appears to be the leading country for number of applications. The theoretical works have been focused mainly on barriers, challenges and success factors. Sustainability, framework for measurement and critical appraisal remain underestimated themes. Evaluations of "system wide approach" are still low in number. Even though Lean results appear to be promising, findings so far do not allow to draw a final word on its positive impacts or challenges when introduced in the healthcare sector. Scholars are called to explore further the potentiality and the weaknesses of Lean, above all as for the magnitude of investments required and for the engagement of the whole organization it represents increasingly strategic choice, whilst health professionals, managers and policy makers could and should learn from research how to play a pivotal role for a more effective implementation of lean in different health contexts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Lean tool used in the automotive industry

    Directory of Open Access Journals (Sweden)

    Manuela Ingaldi

    2014-10-01

    Full Text Available In the paper basic concepts of Lean Manufacturing were presented. A company specializing in the development of vehicle dynamics, driver assistance systems, brake systems, seat belt sand electronics technology was characterized. The company is engaged in designing and manufacturing world-class products for the automotive market. The Lean tools used in the production hall, such as Yamazumi chart, machine motion analysis, MTM method and timing, were presented.

  16. Lean tool used in the automotive industry

    OpenAIRE

    Manuela Ingaldi; Marta Jagusiak-Kocik

    2014-01-01

    In the paper basic concepts of Lean Manufacturing were presented. A company specializing in the development of vehicle dynamics, driver assistance systems, brake systems, seat belt sand electronics technology was characterized. The company is engaged in designing and manufacturing world-class products for the automotive market. The Lean tools used in the production hall, such as Yamazumi chart, machine motion analysis, MTM method and timing, were presented.

  17. Implementing lean manufacturing system: ISM approach

    Directory of Open Access Journals (Sweden)

    Naveen Kumar

    2013-09-01

    Full Text Available Purpose: Lean Manufacturing System has emerged as an important area of research in Indian context. The requirement of Lean Manufacturing has increased due to defects in products (semi finished and finished and subsequent increase in cost. In this context, this study is an attempt to develop a structural model of the variables, important to implement Lean Manufacturing System in Indian automobile industry. Design/Methodology/Approach: Various variables of lean manufacturing system implementation have been identified from literature review and experts’ opinions. Contextual relationship among these identified variables has been set after carrying out brainstorming session. Further, classification of the variables has been carried out based upon the driving power and dependence. In addition to this, a structural model of variables to implement lean concept in Indian automobile industry has also been developed using Interpretive Structural Modeling (ISM technique. Questionnaire based survey has also been conducted to rank these variables. Findings: Eighteen variables have been identified from the literature and subsequent discussions with experts. Out of which, nine variables have been identified as dependent and nine variables have been identified as driver. No variable has been identified as linkage variable and autonomous variable. From the model developed, ‘Relative cost benefits’ has been identified as top level dependent variable and top management commitment as bottom level most independent variable. Research limitations/Implications: The model so developed is a hypothetical model based upon experts’ opinions. The conclusions so drawn may be further modified to apply in real situation. Practical implication: Clear understanding of interactions among these variables will help organizations to prioritize and manage these variables more effectively and efficiently to draw advantage from lean manufacturing system implementation

  18. INNOVATION LEAN PRINCIPLES IN AUTOMOTIVE GREEN MANUFACTURING

    Directory of Open Access Journals (Sweden)

    Dušan Sabadka

    2014-12-01

    Full Text Available Today, industries such as automotive and manufacturing industries deal with a lot of environmental regulations. Lean is a production strategy whose fundamental principles drive the industry towards a more effective production of goods and services. The eco-efficiency concept is primary to sustainable development and intends to provide more value with less environmental impact. The aim of this study is to identify and explore the contributions of Lean to reduce environmental impacts that naturally result from industrial activity.

  19. Low NO sub x heavy fuel combustor concept program. Phase 1A: Combustion technology generation coal gas fuels

    Science.gov (United States)

    Sherlock, T. P.

    1982-01-01

    Combustion tests of two scaled burners using actual coal gas from a 25 ton/day fluidized bed coal gasifier are described. The two combustor configurations studied were a ceramic lined, staged rich/lean burner and an integral, all metal multiannual swirl burner (MASB). The tests were conducted over a range of temperature and pressures representative of current industrial combustion turbine inlet conditions. Tests on the rich lean burner were conducted at three levels of product gas heating values: 104, 197 and 254 btu/scf. Corresponding levels of NOx emissions were 5, 20 and 70 ppmv. Nitrogen was added to the fuel in the form of ammonia, and conversion efficiencies of fuel nitrogen to NOx were on the order of 4 percent to 12 percent, which is somewhat lower than the 14 percent to 18 percent conversion efficiency when src-2 liquid fuel was used. The MASB was tested only on medium btu gas (220 to 270 btu/scf), and produced approximately 80 ppmv NOx at rated engine conditions. Both burners operated similarly on actual coal gas and erbs fuel, and all heating values tested can be successfully burned in current machines.

  20. Simulation of thermal effectiveness under coal dust burning

    International Nuclear Information System (INIS)

    Korabejnikova, V.K.

    2001-01-01

    The simulation equation of polydisperse fuel (coal dust) torch combustion in the definite zones of burning cameras of stream generator and taking into account reactions in kinetic and diffusion areas at distinguishing temperatures of particles and gas are considered. (author)

  1. Emissions from biomass burning in the Yucatan

    Science.gov (United States)

    R. J. Yokelson; J. D. Crounse; P. F. DeCarlo; T. Karl; S. Urbanski; E. Atlas; T. Campos; Y. Shinozuka; V. Kapustin; A. D. Clarke; A. Weinheimer; D. J. Knapp; D. D. Montzka; J. Holloway; P. Weibring; F. Flocke; W. Zheng; D. Toohey; P. O. Wennberg; C. Wiedinmyer; L. Mauldin; A. Fried; D. Richter; J. Walega; J. L. Jimenez; K. Adachi; P. R. Buseck; S. R. Hall; R. Shetter

    2009-01-01

    In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/ US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle...

  2. The promise of Lean in health care.

    Science.gov (United States)

    Toussaint, John S; Berry, Leonard L

    2013-01-01

    An urgent need in American health care is improving quality and efficiency while controlling costs. One promising management approach implemented by some leading health care institutions is Lean, a quality improvement philosophy and set of principles originated by the Toyota Motor Company. Health care cases reveal that Lean is as applicable in complex knowledge work as it is in assembly-line manufacturing. When well executed, Lean transforms how an organization works and creates an insatiable quest for improvement. In this article, we define Lean and present 6 principles that constitute the essential dynamic of Lean management: attitude of continuous improvement, value creation, unity of purpose, respect for front-line workers, visual tracking, and flexible regimentation. Health care case studies illustrate each principle. The goal of this article is to provide a template for health care leaders to use in considering the implementation of the Lean management system or in assessing the current state of implementation in their organizations. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  3. Lean healthcare from a change management perspective.

    Science.gov (United States)

    van Rossum, Lisa; Aij, Kjeld Harald; Simons, Frederique Elisabeth; van der Eng, Niels; Ten Have, Wouter Dirk

    2016-05-16

    Purpose - Lean healthcare is used in a growing number of hospitals to increase efficiency and quality of care. However, healthcare organizations encounter problems with the implementation of change initiatives due to an implementation gap: the gap between strategy and execution. From a change management perspective, the purpose of this paper is to increase scientific knowledge regarding factors that diminish the implementation gap and make the transition from the "toolbox lean" toward an actual transformation to lean healthcare. Design/methodology/approach - A cross-sectional study was executed in an operating theatre of a Dutch University Medical Centre. Transformational leadership was expected to ensure the required top-down commitment, whereas team leadership creates the required active, bottom-up behavior of employees. Furthermore, professional and functional silos and a hierarchical structure were expected to impede the workforce flexibility in adapting organizational elements and optimize the entire process flow. Findings - The correlation and regression analyses showed positive relations between the transformational leadership and team leadership styles and lean healthcare implementation. The results also indicated a strong relation between workforce flexibility and the implementation of lean healthcare. Originality/value - With the use of a recently developed change management model, the Change Competence Model, the authors suggest leadership and workforce flexibility to be part of an organization's change capacity as crucial success factor for a sustainable transformation to lean healthcare.

  4. Implementing Lean Health Reforms in Saskatchewan

    Directory of Open Access Journals (Sweden)

    Greg Marchildon

    2013-07-01

    Full Text Available Saskatchewan has gone further than any other Canadian province in implementing health system process improvements using Lean, a production line discipline that originated with the automobile industry. The goal of the Lean reform is to reduce waste and improve quality and overall health system performance by long-term changes in behaviour. Lean enjoys a privileged position on the provincial government’s agenda because of the policy’s championing by the Deputy Minister of Health and the policy’s fit with the government’s patient-centred care agenda. The implementation of reform depends on a major investment of time in the training and Lean-certification of key leaders and managers in the provincial health system. The Saskatchewan Union of Nurses, the union representing the single largest group of health workers in the province, has agreed to co-operate with the provincial government in implementing Lean-type reforms. Thus far, the government has had limited independent evaluation of Lean while internal evaluations claim some successes.

  5. Burn mouse models

    DEFF Research Database (Denmark)

    Calum, Henrik; Høiby, Niels; Moser, Claus

    2014-01-01

    Severe thermal injury induces immunosuppression, involving all parts of the immune system, especially when large fractions of the total body surface area are affected. An animal model was established to characterize the burn-induced immunosuppression. In our novel mouse model a 6 % third-degree b......Severe thermal injury induces immunosuppression, involving all parts of the immune system, especially when large fractions of the total body surface area are affected. An animal model was established to characterize the burn-induced immunosuppression. In our novel mouse model a 6 % third...... with infected burn wound compared with the burn wound only group. The burn mouse model resembles the clinical situation and provides an opportunity to examine or develop new strategies like new antibiotics and immune therapy, in handling burn wound victims much....

  6. Visual communication in lean organizations

    Directory of Open Access Journals (Sweden)

    Iuga Maria Virginia

    2017-01-01

    Full Text Available Many researchers have studied the role and importance of communication and communication types for organizations and their work force. The topic of organizational communication is a constantly changing one. The thing that remains stable throughout this very wide topic is its purpose: communication is vital for the effectiveness and success of organizations of all sizes, types and cultures. In terms of type, one could split up topic by type as followed: verbal, visual and written. This research paper focuses on the visual component at shop floor within automotive organizations. It aims at giving the reader a structured overview on the most appropriate but also lean visual communication practices. In order to establish these methods at shop floor, a survey was conducted among nine big automotive companies in Romania. It was then followed up by a second survey dedicated to check the effectiveness of implementation of these methods in a big automotive organization. The paper presents the analyses, results and the conclusions of this surveys.

  7. The Burning Saints

    DEFF Research Database (Denmark)

    Xygalatas, Dimitris

    . Carrying the sacred icons of the saints, participants dance over hot coals as the saint moves them. The Burning Saints presents an analysis of these rituals and the psychology behind them. Based on long-term fieldwork, The Burning Saints traces the historical development and sociocultural context......, The Burning Saints presents a highly original analysis of how mental processes can shape social and religious behaviour....

  8. Burning mouth syndrome

    OpenAIRE

    K A Kamala; S Sankethguddad; S G Sujith; Praveena Tantradi

    2016-01-01

    Burning mouth syndrome (BMS) is multifactorial in origin which is typically characterized by burning and painful sensation in an oral cavity demonstrating clinically normal mucosa. Although the cause of BMS is not known, a complex association of biological and psychological factors has been identified, suggesting the existence of a multifactorial etiology. As the symptom of oral burning is seen in various pathological conditions, it is essential for a clinician to be aware of how to different...

  9. Technology for emission control in internal combustion engines; Kakushu nainen kikan ni okeru hai gas joka gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shioji, M. [Kyoto University, Kyoto (Japan)

    1998-09-01

    Described herein are emission control technology and exhaust gas cleaning measures for internal combustion engines. Gas turbines burn relatively high-quality fuels, such as natural gas, kerosene, diesel oil and gas oil, where the major concerns are to reduce NOx and dust emissions. The NOx abatement techniques fall into two general categories; wet processes which inject water or steam, and dry processes which depend on improved combustion. Power generation and cogeneration which burn natural gas adopt lean, premixed combustion and two-stage combustion as the major approaches. Low-speed, large-size diesel engines, which realize very high thermal efficiency, discharge high concentrations of NOx. Delayed fuel injection timing is the most easy NOx abatement technique to meet the related regulations, but is accompanied by decreased fuel economy. Use of water-emulsified fuel, water layer injection and multi-port injection can reduce NOx emissions without decreasing fuel economy, depending on optimization methods adopted. Automobile gasoline engines are required to further clean exhaust gases by catalystic systems. 9 refs., 10 figs., 6 tabs.

  10. Choosing Wood Burning Appliances

    Science.gov (United States)

    Information to assist consumers in choosing a wood burning appliance, including types of appliances, the differences between certified and non-certified appliances, and alternative wood heating options.

  11. Lean i Norge : opplever norske bedrifter som er mer lean, større økning i kundetilfredshet enn de som er mindre lean?

    OpenAIRE

    Fagereng, Hanne Eline; Askevold, Elisabeth Cathrine

    2010-01-01

    Vi ønsker å måle i hvor stor grad norske bedrifter har implementert lean, og for å måle grad av lean har vi utviklet et rammeverk basert på lean teori. Hovedformålet med lean er å øke kundeverdi med minst mulig ressursbruk, anstrengelse, energi, utstyr, tid, plass, material og kapital (Womack, Roos and Jones 2007). Vi vil utforske om høyere grad av lean fører til mer tilfredse kunder enn de som har lavere grad av lean. Altså om hovedformålet med lean blir oppnådd hvis man implementerer lean i...

  12. CO Emissions from Gas Engines Operating on Biomass Producer Gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper; Jensen, T. K.; Henriksen, Ulrik Birk

    2004-01-01

    High carbon monoxide (CO) emission from gas engines fueled by producer gas is a concerning problem in the struggle to make biomass gasification for heat and power production a success. CO emissions from engines operating on biomass producer gases are high, especially at very lean conditions where...

  13. Using Dynamic Value Stream Mapping and Lean Accounting Box Scores to Support Lean Implementation

    Science.gov (United States)

    Woehrle, Stephen L.; Abou-Shady, Louay

    2010-01-01

    Lean has proven to be an effective management philosophy for improving businesses in a competitive market by eliminating waste and improving operations. An impact of implementing lean projects is the rapid reduction in inventory levels, which gives management the false impression that profits are decreasing while workers on the shop floor observe…

  14. Worldwide gas marketing

    International Nuclear Information System (INIS)

    Carson, M.M.

    1994-01-01

    Natural gas is an important source of energy throughout the world due to its availability and clean burning characteristics. From liquefied natural gas being shipped via tanker from Alaska to Japan, to natural gas via pipeline from Canada to the US, to inter-country natural gas shipment within the European continent, natural gas continues to expand and justify its place of honor in the world energy picture

  15. Burns and military clothing.

    Science.gov (United States)

    McLean, A D

    2001-02-01

    Burn injury is a ubiquitous threat in the military environment. The risks during combat are well recognised, but the handling of fuel, oil, munitions and other hot or flammable materials during peacetime deployment and training also imposes an inherent risk of accidental burn injury. Over the last hundred years, the burn threat in combat has ranged from nuclear weapons to small shoulder-launched missiles. Materials such as napalm and white phosphorus plainly present a risk of burn, but the threat extends to encompass personnel in vehicles attacked by anti-armour weapons, large missiles, fuel-air explosives and detonations/conflagrations on weapons platforms such as ships. Large numbers of burn casualties were caused at Pearl Harbor, in Hiroshima and Nagasaki, Vietnam, during the Arab/Israeli Wars and in the Falkland Islands conflict. The threat from burns is unlikely to diminish, indeed new developments in weapons seek to exploit the vulnerability of the serviceman and servicewoman to burns. Clothing can be a barrier to some types of burn--both inherently in the properties of the material, but also by trapping air between clothing layers. Conversely, ignition of the clothing may exacerbate a burn. There is hearsay that burnt clothing products within a wound may complicate the clinical management, or that materials that melt (thermoplastic materials) should not be worn if there is a burn threat. This paper explores the incidence of burn injury, the mechanisms of heat transfer to bare skin and skin covered by materials, and the published evidence for the complication of wound management by materials. Even light-weight combat clothing can offer significant protection to skin from short duration flash burns; the most vulnerable areas are the parts of the body not covered--face and hands. Multilayered combat clothing can offer significant protection for short periods from engulfment by flames; lightweight tropical wear with few layers offers little protection. Under

  16. Implementation of NOx emissions standard in the Gas Transmission Company in the Netherlands

    International Nuclear Information System (INIS)

    Veenstra, T.; Coors, P.; Rosmalen, R.J.

    1992-01-01

    In 1987 and 1990 new NO x emission standards came in force for firing installations (boilers, gas turbines and engines). Gasunie (the gas transportation company in The Netherlands) owns 55 gas turbines and 10 gas engines for the gastransport system, with a total capacity of about 570 MW, installed in 8 compressor stations. Having the most stringent emission levels of Europe (together with Germany) Gasunie reduced the total NO x amount from 3600 tons of NO x in 1987 to 630 tons of NO x in 1990. This reduction was mostly based on our own development of a new precombustion chamber for the lean burn gas engines. Besides that studies and research were carried out for NO x reduction on the gas turbine to meet the current legislation (115 ppm NO x ) and a strategy is made to meet future emission standards. This is necessary because the expected future NO x standards for stand alone gas turbines will be about half of the present standards

  17. The relationships between Lean manufacturing, management accounting and firm performance

    DEFF Research Database (Denmark)

    Kristensen, Thomas Borup; Nielsen, Henrik; Grasso, Lawrency

    2016-01-01

    with management accounting practices. Specifically, we document that Lean manufacturing is positively associated with Value Stream Costing, Lean visual controls and, more importantly, measures of labor and materials efficiency. Lean manufacturing is positively related to Lean thinking and both are positively...... associated with operational performance and so are Lean visual controls. We also document that the management accounting practices intervene affecting operational performance and they intervene with Lean thinking as well. Lastly, the relationship between Lean manufacturing and measures of labor and materials......Lean manufacturing has been adopted by numerous western companies as an answer to an increasing competitive environment. Lean manufacturing is seen as an enterprise-wide strategy encompassing a transformation of manufacturing practices, affecting companies’ management accounting practices and...

  18. Tourniquet associated chemical burn

    Directory of Open Access Journals (Sweden)

    Jae-Hyuk Yang

    2012-01-01

    Full Text Available Chemical burn under pneumatic tourniquet is an iatrogenic preventable injury and is rarely reported in the literature. The two important mechanisms are maceration (friction and wetness underneath the tourniquent. In this report, our experience with two illustrative patients who presented with iatrogenic tourniquet associated burn is described.

  19. Burns (For Parents)

    Science.gov (United States)

    ... small, and have sensitive skin that needs extra protection. Although some minor burns aren't cause for concern and can ... burns, the mildest of the three, are limited to the top layer of skin: Signs ... pain, and minor swelling. The skin is dry without blisters. Healing ...

  20. Implementing lean in Malaysian universities: Lean awareness level in an engineering faculty of a local university

    Science.gov (United States)

    Azim Khairi, M.; Rahman, Mohamed Abd

    2018-01-01

    Many academic articles were published in Malaysia promoting the goodness of lean in manufacturing and industrial sectors but less attention was apparently given to the possibility of obtaining the same universal benefits when applying lean in non-manufacturing sectors especially higher education. This study aims to determine the level of lean awareness among a local university’s community taking its Faculty of Engineering (FoE) as the case study. It also seeks to identify typical FoE’s staff perception on lean regarding its benefits and the obstacles in implementing it. A web-based survey using questionnaires was carried out for 215 respondents consisting of academic and administrative staff of the faculty. Statistical Package for the Social Science (SPSS) was used to analyze the survey data collected. A total of 13.95% of respondents returned the forms. Slightly more than half of those responded (56.7%) have encountered some of the lean terms with mean 1.43 and standard deviation 0.504. However, the large amount of standard deviation somewhat indicates that the real level of lean awareness of FoE as a group was low. In terms of lean benefits, reduction of waste was favored (93.3%) by the respondents with mean 0.93 and standard deviation 0.254. For obstacles in implementing lean, lack of knowledge was selected by most respondents (86.7%) to be the major factor with mean 0.87 and standard deviation 0.346. Through the analysis done, the study may conclude that level of lean awareness among the university‘s community was low thus may hinder implementation of lean concept.

  1. Burning mouth syndrome

    Directory of Open Access Journals (Sweden)

    K A Kamala

    2016-01-01

    Full Text Available Burning mouth syndrome (BMS is multifactorial in origin which is typically characterized by burning and painful sensation in an oral cavity demonstrating clinically normal mucosa. Although the cause of BMS is not known, a complex association of biological and psychological factors has been identified, suggesting the existence of a multifactorial etiology. As the symptom of oral burning is seen in various pathological conditions, it is essential for a clinician to be aware of how to differentiate between symptom of oral burning and BMS. An interdisciplinary and systematic approach is required for better patient management. The purpose of this study was to provide the practitioner with an understanding of the local, systemic, and psychosocial factors which may be responsible for oral burning associated with BMS, and review of treatment modalities, therefore providing a foundation for diagnosis and treatment of BMS.

  2. Phoenix Society for Burn Survivors

    Science.gov (United States)

    ... in 2018! Learn More For Loved Ones A burn injury doesn't just impact the survivor. Families ... to support longterm recovery, improve the quality of burn care, and prevent burn injury. Explore articles on ...

  3. Optimization of large scale food production using Lean Manufacturing principles

    DEFF Research Database (Denmark)

    Engelund, Eva Høy; Friis, Alan; Breum, Gitte

    2009-01-01

    This paper discusses how the production principles of Lean Manufacturing (Lean) can be applied in a large-scale meal production. Lean principles are briefly presented, followed by a field study of how a kitchen at a Danish hospital has implemented Lean in the daily production. In the kitchen...... not be negatively affected by the rationalisation of production procedures. The field study shows that Lean principles can be applied in meal production and can result in increased production efficiency and systematic improvement of product quality without negative effects on the working environment. The results...... show that Lean can be applied and used to manage the production of meals in the kitchen....

  4. Lean Manufacturing Auto Cluster at Chennai

    Science.gov (United States)

    Bhaskaran, E.

    2012-10-01

    Due the presence of lot of automotive Industry, Chennai is known as Detroit of India, that producing over 40 % of the Indian vehicle and components. Lean manufacturing concepts have been widely recognized as an important tool in improving the competitiveness of industries. This is a continuous process involving everyone, starting from management to the shop floor. Automotive Component Industries (ACIs) in Ambattur Industrial Estate, Chennai has formed special purpose vehicle (SPV) society namely Ambattur Industrial Estate Manufacturers Association (AIEMA) Technology Centre (ATC) lean manufacturing cluster (ATC-LMC) during July 2010 under lean manufacturing competitiveness scheme, that comes under National Manufacturing Competitiveness Programme of Government of India. The Tripartite Agreement is taken place between National Productivity Council, consultants and cluster (ATC-LMC). The objective is to conduct diagnostic study, study on training and application of various lean manufacturing techniques and auditing in ten ACIs. The methodology adopted is collection of primary data/details from ten ACIs. In the first phase, diagnostic study is done and the areas for improvement in each of the cluster member companies are identified. In the second phase, training programs and implementation is done on 5S and other areas. In the third phase auditing is done and found that the lean manufacturing techniques implementation in ATC-LMC is sustainable and successful in every cluster companies, which will not only enhance competitiveness but also decrease cost, time and increase productivity. The technical efficiency of LMC companies also increases significantly.

  5. Lean oncology: a new model for oncologists

    Directory of Open Access Journals (Sweden)

    Montesarchio Vincenzo

    2012-04-01

    Full Text Available Abstract The history of the term Lean is relatively recent and originates from the Toyota Production System (TPS. The term "Lean" means "thin", which refers to a mental process, operational, productive, no-frills, quick but not hasty, consequential to the previous event. The Lean process flows seamlessly into the result, eliminates unnecessary complications to the effect, prevents unnecessary equipment processes. The idea is to 'do more with less', like using the (few available resources in the most productive way possible, through the elimination of all types of waste that inevitably accompanies every stage of a production process. Lean management is primarily a management philosophy, a system of values and behaviors that goes beyond the mere application of the instrument and that, once internalized, will form the nucleus of the corporate culture. "Lean Oncology" is a term coined to identify a methodology of care and treatment to cancer patients, consisting on process simplification, streamlining of the organizational and routes of drug treatment, detection and elimination of waste. Its main objective is the centrality of the patient.

  6. Lean oncology: a new model for oncologists.

    Science.gov (United States)

    Montesarchio, Vincenzo; Grimaldi, Antonio Maria; Fox, Bernard A; Rea, Antonio; Marincola, Francesco M; Ascierto, Paolo A

    2012-04-25

    The history of the term Lean is relatively recent and originates from the Toyota Production System (TPS). The term "Lean" means "thin", which refers to a mental process, operational, productive, no-frills, quick but not hasty, consequential to the previous event. The Lean process flows seamlessly into the result, eliminates unnecessary complications to the effect, prevents unnecessary equipment processes. The idea is to 'do more with less', like using the (few) available resources in the most productive way possible, through the elimination of all types of waste that inevitably accompanies every stage of a production process. Lean management is primarily a management philosophy, a system of values and behaviors that goes beyond the mere application of the instrument and that, once internalized, will form the nucleus of the corporate culture. "Lean Oncology" is a term coined to identify a methodology of care and treatment to cancer patients, consisting on process simplification, streamlining of the organizational and routes of drug treatment, detection and elimination of waste. Its main objective is the centrality of the patient.

  7. LEAN PRACTICES FOR PRODUCT DEVELOPMENT PROCESS

    Directory of Open Access Journals (Sweden)

    Guilherme Luz Tortorella

    2015-06-01

    Full Text Available Lean product development (LPD is an approach that comprises lean principles and management practices that aim to reduce waste and improve operational effectiveness throughout the entire value stream in continuous improvement endless journey. Due to that, the ability to innovate, change and learn continuously is a key element in order to minimize product development problems. Several LPD techniques are presented in the literature as possible enablers for lean implementation. However, little has been known about the impact of these enablers on the problems related to product development processes. Thus, this paper aims to examine the relationship between five LPD practices’ constructs and the occurrence frequency of eleven LPD problems’ constructs in companies that are implementing lean. Moreover, the identification of relevant relationships between LPD practices’ and problems’ constructs may contribute to specify the contexts in which problems are expected to occur. The study sample comprises sixty four companies already undergoing lean implementation both in shop floor and offices area. The results indicate that the same practices’ constructs, which are deemed as influential for minimizing LPD problems, present different relationship intensities among them.

  8. Using Lean to Advance Quality Improvement Research.

    Science.gov (United States)

    Blackmore, Christopher Craig; Williams, Barbara L; Ching, Joan M; Chafetz, Lynne A; Kaplan, Gary S

    2016-01-01

    Quality improvement research skills are not commonplace among quality improvement practitioners, and research on the effectiveness of quality improvement has not always kept pace with improvement innovation. However, the Lean tools applied to quality improvement should be equally relevant to the advancement of quality improvement research. We applied the Lean methods to develop a simplified quality improvement publication pathway enabling a small research methodology group to increase quality improvement research throughout the institution. The key innovations of the pathway are horizontal integration of the quality improvement research methods group across the institution, implementation of a Lean quality improvement research pathway, and application of a just-in-time quality improvement research toolkit. This work provides a road map and tools for the acceleration of quality improvement research. At our institution, the Lean quality improvement research approach was associated with statistically significant increases in the number (annual mean increase from 3.0 to 8.5, p = .03) and breadth of published quality improvement research articles, and in the number of quality improvement research projects currently in process. Application of Lean methods to the quality improvement research process can aid in increasing publication of quality improvement articles from across the institution.

  9. Bevezetés a lean menedzsmentbe – a lean stratégiai alapjai = Introduction to lean management – basic strategic elements of lean

    OpenAIRE

    Losonci, Dávid

    2010-01-01

    A lean menedzsment az értékteremtő folyamatok stratégiai és operatív szintjének meghatározó formálójává vált az elmúlt évtizedekben. Jelen tanulmány stratégiai nézőpontból tárgyalja a lean menedzsment teljes bevezetését. Részletes áttekintést ad a Womack és Jones (2003) által lefektetett lean alapelvekről. Az operatív teljesítményjavulásból származó vevői értékteremtés mellett foglalkozik a tulajdonosi értékteremtéssel, az MRP és a lean szinergikus összekapcsolásával, valamint a lean ideális ...

  10. Contact palm burns in toddlers from glass enclosed fireplaces.

    Science.gov (United States)

    Dunst, C M; Scott, E C; Kraatz, J J; Anderson, P M; Twomey, J A; Peltier, G L

    2004-01-01

    We have seen an alarming increase in the incidence of pediatric palm burns associated with gas fireplaces. The increasing popularity of these units places more children at risk. Medical records of patients under the age of 5 years who sustained hand burns from contact with the glass enclosure of gas fireplaces from 1996 through 2002 were reviewed. Thirty-nine patients were identified, with a mean age of 12.8 months. A 15-fold increase in incidence was observed. Thirty-three patients suffered superficial second-degree burns that were treated conservatively. Twenty-one percent of children developed significant wound complications requiring intensive therapy including extension splinting or surgery. Pediatric burns resulting from palmar contact with the glass enclosures of gas fireplaces have emerged as an avoidable new danger within the home. Although most of these injuries heal with conservative treatment alone, many require surgery or other intensive management to regain acceptable function.

  11. The Development Of A Theoretical Lean Culture Causal Framework To Support The Effective Implementation Of Lean In Automotive Component Manufacturers

    Directory of Open Access Journals (Sweden)

    Van der Merwe, Karl Robert

    2014-05-01

    Full Text Available Although it is generally accepted that lean manufacturing improves operational performance, many organisations are struggling to adapt to the lean philosophy. The purpose of this study is to contribute to a more effective strategy for implementing the lean manufacturing improvement philosophy. The study sets out both to integrate well-researched findings and theories related to generic organisational culture with more recent research and experience related to lean culture, and to examine the role that culture plays in the effective implementation of lean manufacturing principles and techniques. The ultimate aim of this exercise is to develop a theoretical lean culture causal framework.

  12. Lean for Government: Eliminating the Seven Wastes

    Science.gov (United States)

    Shepherd, Christena C.

    2012-01-01

    With shrinking budgets and a slow economy, it is becoming increasingly important for all government agencies to become more efficient. Citizens expect and deserve efficient and effective services from federal, state and local government agencies. One of the best methods to improve efficiency and eliminate waste is to institute the business process improvement methodologies known collectively as Lean; however, with reduced budgets, it may not be possible to train everyone in Lean or to engage the services of a trained consultant. It is possible, however, to raise awareness of the "Seven Wastes" of Lean in each employee, and encourage them to identify areas for improvement. Management commitment is vital to the success of these initiatives, and it is also important to develop the right metrics that will track the success of these changes.

  13. Contribution of Lean Management to Excellence

    Directory of Open Access Journals (Sweden)

    López-Fresno Palmira

    2014-11-01

    Full Text Available To continuously and systematically improve efficiency and efficacy of processes, organizations need the implication of all employees in continuous improvement and innovation through suitable Quality Management Programs (QMPs. Effectiveness of these programs is directly linked to the requirement employees understand the methodologies and tools used for QM and the benefits that will derivate from their implementation, individually and collectively, so they can commit and implicate. Lean Management is a friendly methodology to continuously and systematically achieve process improvement, so helping the organization seeking operational excellence that contributes to overall excellence. This paper identifies Critical Success Factors (CSFs for an effective implementation of QMPs, suggests Lean Management as an easy-to-understand, powerful and friendly methodology for operational excellence and overall excellence, and presents a case experience of implementation of Lean Management in a health care organization that applies the EFQM model, and the lessons learnt.

  14. Lean Start-up in Established Companies

    DEFF Research Database (Denmark)

    Goduscheit, René Chester

    2018-01-01

    Lean start-up is an emergent perspective on how entrepreneurs can bring new products and services to the market. This approach challenges the dominant role of lengthy business plans, linear product development processes, and seeking complete overview of the potential of the new products....../services before market launch. Instead it suggests that start-ups could benefit from a ‘minimum-viable product’ approach where products and services are launched when they contain critical features. The emphasis in the lean start-up approach is on business models rather than the elaborate business plan...... at the companies (strategy meetings, development workshops etc.). The aim is to shed light on the implications for companies that seek to employ lean start-up. These implications will be aimed at aspects like innovation management, organizational structure, customer relations etc....

  15. Theories of lean management: an empirical evaluation.

    Science.gov (United States)

    Handel, Michael J

    2014-03-01

    Debates within organization theory traditionally argued the relative merits of bureaucracy but today there is broad agreement across different perspectives that bureaucratic organization is inefficient and outmoded. Despite their differences, post-bureaucratic and neo-liberal theories argue that organizations with relatively flat hierarchies and low management overhead are better adapted to current market requirements. Post-bureaucratic theory also argues that employees, as well as firms, benefit from leaner management structures. This paper investigates trends in managerial leanness, proposed explanations for such trends, and the consequences of leanness for firms and employees. Although there is a trend toward flatter management hierarchies, there is only weak support for current claims regarding both the causes and consequences of lean management. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Survey of modern power plants driven by diesel and gas engines

    Energy Technology Data Exchange (ETDEWEB)

    Niemi, S [Turku Polytechnic, Turku (Finland)

    1998-12-31

    between 35 % and 47 %. The total efficiency of a CHP plant depends on its heat recovery system, recording at its highest rating 98 % efficiency. Exhaust emissions of IC engine power plants must be reduced both by internal and post-combustion methods. The lean-burn SI gas engines seem better with regard to engine-out emissions, while other gas and oil-driven engines with higher oxides of nitrogen emissions are worse. The report deals only with post-combustion exhaust cleaning systems, reporting on the development of selective catalytic processes (SCR) and three-way catalysts. Data was also collected on combined oxi-cat and SCR reactors and NO reduction concepts that utilize other media than ammonia or urea, as well as more advanced post-combustion methods. (orig.) 60 refs.

  17. Survey of modern power plants driven by diesel and gas engines

    Energy Technology Data Exchange (ETDEWEB)

    Niemi, S. [Turku Polytechnic, Turku (Finland)

    1997-12-31

    between 35 % and 47 %. The total efficiency of a CHP plant depends on its heat recovery system, recording at its highest rating 98 % efficiency. Exhaust emissions of IC engine power plants must be reduced both by internal and post-combustion methods. The lean-burn SI gas engines seem better with regard to engine-out emissions, while other gas and oil-driven engines with higher oxides of nitrogen emissions are worse. The report deals only with post-combustion exhaust cleaning systems, reporting on the development of selective catalytic processes (SCR) and three-way catalysts. Data was also collected on combined oxi-cat and SCR reactors and NO reduction concepts that utilize other media than ammonia or urea, as well as more advanced post-combustion methods. (orig.) 60 refs.

  18. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    Energy Technology Data Exchange (ETDEWEB)

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2006-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  19. Waste Measurement Techniques For Lean Companies

    Directory of Open Access Journals (Sweden)

    Maciej Pieńkowski

    2014-12-01

    Full Text Available The paper is dedicated to answer the problem of measuring waste in companies, which are implementing Lean Manufacturing concept. Lack of complex identification, quantification an visualization of waste significantly impedes Lean transformation efforts. This problem can be solved by a careful investigation of Muda, Muri and Mura, which represent the essence of waste in the Toyota Production System. Measuring them facilitates complete and permanent elimination of waste in processes. The paper introduces a suggestion of methodology, which should enable company to quantify and visualize waste at a shop floor level.

  20. A Lean Six Sigma journey in radiology.

    Science.gov (United States)

    Bucci, Ronald V; Musitano, Anne

    2011-01-01

    The department of radiology at Akron Children's Hospital embarked on a Lean Six Sigma mission as part of a hospital wide initiative to show increased customer satisfaction, reduce employee dissatisfaction and frustration, and decrease costs. Three processes that were addressed were reducing the MRI scheduling back-log, reconciling discrepancies in billing radiology procedures, and implementing a daily management system. Keys to success is that managers provide opportunities to openly communicate between department sections to break down barriers. Executive leaders must be engaged in Lean Six Sigma for the company to be successful.

  1. The Lean and Global Start-up

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager

    For several decades researchers have studied start-up companies with a focus on international markets, suppliers and networks from their inception and on companies that are establishing new, agile business models. This has resulted in two streams of research: The Born Global and International New...... Ventures research and research with a focus on the Lean Start-up company. It is our intention in this paper to give a short presentation of the two research streams and show how they can be merged into one with a focus on newly established technology oriented firms that are lean and global from...

  2. Wood would burn

    International Nuclear Information System (INIS)

    Swithenbank, Jim; Chen, Qun; Zhang, Xiaohui; Sharifi, Vida; Pourkashanian, Mohamed

    2011-01-01

    Absract: In view of the world-wide problem of energy sustainability and greenhouse gas production (carbon dioxide), it is timely to review the issues involved in generating heat and power from all fuels and especially new (to the UK) solid fuels, including high moisture fuels such as wood, SRF, oil shale, tar sands and brown coal, which will become major international fuels as oil and gas become depleted. The combustion properties of some of these materials are significantly different from traditional coal, oil and gas fuels, however the technology proposed herein is also applicable to these conventional fuels. This paper presents some innovative combustion system options and the associated technical factors that must be considered for their implementation. For clarity of understanding, the novel concepts will be largely presented in terms of a currently developing solid fuel market; biomass wood chips. One of the most important characteristics of many solid fuels to be used in the future (including oil shale and brown coal) is their high moisture content of up to 60%. This could be removed by utilising low grade waste heat that is widely available in industry to dry the fuel and thus reduce transport costs. Burning such dried wood for power generation also increases the energy available from combustion and thus acts as a thermal transformer by upgrading the low grade heat to heat available at combustion temperatures. The alternative approach presented here is to recover the latent heat by condensing the extrinsic moisture and the water formed during combustion. For atmospheric combustion, the temperature of the condensed combustion products is below the dew point at about 55-65 o C and is only suitable for recovery in an efficient district heating system. However, in order to generate power from the latent heat, the condensation temperature must be increased to the level where the heat can be used in the thermodynamic power cycle. This can be achieved by

  3. Improving burn care and preventing burns by establishing a burn database in Ukraine.

    Science.gov (United States)

    Fuzaylov, Gennadiy; Murthy, Sushila; Dunaev, Alexander; Savchyn, Vasyl; Knittel, Justin; Zabolotina, Olga; Dylewski, Maggie L; Driscoll, Daniel N

    2014-08-01

    Burns are a challenge for trauma care and a contribution to the surgical burden. The former Soviet republic of Ukraine has a foundation for burn care; however data concerning burns in Ukraine has historically been scant. The objective of this paper was to compare a new burn database to identify problems and implement improvements in burn care and prevention in this country. Retrospective analyses of demographic and clinical data of burn patients including Tukey's post hoc test, analysis of variance, and chi square analyses, and Fisher's exact test were used. Data were compared to the American Burn Association (ABA) burn repository. This study included 1752 thermally injured patients treated in 20 hospitals including Specialized Burn Unit in Municipal Hospital #8 Lviv, Lviv province in Ukraine. Scald burns were the primary etiology of burns injuries (70%) and burns were more common among children less than five years of age (34%). Length of stay, mechanical ventilation use, infection rates, and morbidity increased with greater burn size. Mortality was significantly related to burn size, inhalation injury, age, and length of stay. Wound infections were associated with burn size and older age. Compared to ABA data, Ukrainian patients had double the length of stay and a higher rate of wound infections (16% vs. 2.4%). We created one of the first burn databases from a region of the former Soviet Union in an effort to bring attention to burn injury and improve burn care. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  4. Lean Transformation Guidance: Why Organizations Fail To Achieve and Sustain Excellence Through Lean Improvement

    OpenAIRE

    Mohammed Hamed Ahmed

    2013-01-01

    Many companies are complaining that lean didn’t achieve their long-term goals, and the improvement impact was very short-lived. 7 out of each 10 lean projects fail as companies try to use lean like a toolkit, copying and pasting the techniques without trying to adapt the employee’s culture, manage the improvement process, sustain the results, and develop their leaders. When the Toyota production system was created, the main goal was to remove wastes from the shop floor us...

  5. Development of framework for sustainable Lean implementation: an ISM approach

    Science.gov (United States)

    Jadhav, Jagdish Rajaram; Mantha, S. S.; Rane, Santosh B.

    2014-07-01

    The survival of any organization depends upon its competitive edge. Even though Lean is one of the most powerful quality improvement methodologies, nearly two-thirds of the Lean implementations results in failures and less than one-fifth of those implemented have sustained results. One of the most significant tasks of top management is to identify, understand and deploy the significant Lean practices like quality circle, Kanban, Just-in-time purchasing, etc. The term `bundle' is used to make groups of inter-related and internally consistent Lean practices. Eight significant Lean practice bundles have been identified based on literature reviewed and opinion of the experts. The order of execution of Lean practice bundles is very important. Lean practitioners must be able to understand the interrelationship between these practice bundles. The objective of this paper is to develop framework for sustainable Lean implementation using interpretive structural modelling approach.

  6. Lean Production and information technology : Connection or contradiction?

    NARCIS (Netherlands)

    Riezebos, Jan; Klingenberg, Warse; Hicks, Christian

    The principles of Lean Production have enabled organisations in the manufacturing and service sectors to significantly improve their competitiveness. The application of Lean principles, derived from the Toyota Production System has enabled many organisations to Simultaneously improve productivity,

  7. Working group report: methane emissions from biomass burning

    International Nuclear Information System (INIS)

    Delmas, R.A.; Ahuja, D.

    1993-01-01

    Biomass burning is a significant source of atmospheric methane. Like most other sources of methane, it has both natural and anthropogenic causes, although anthropogenic causes now predominate. Most of the estimates of methane emissions from biomass burning in the past have relied on a uniform emission factor for all types of burning. This results in the share of trace gas emissions for different types of burning being the same as the amounts of biomass burned in those types. The Working Group endorsed the extension of an approach followed for Africa by Delmas et al. (1991) to use different emission factors for different types of biomass burning to estimate national emissions of methane. This is really critical as emission factors present important variations. While the focus of discussions of the Working Group was on methane emissions from biomass burning, the Group endorsed the IPCC-OECD methodology of estimating all greenhouse related trace gases from biomass burning. Neither the IPCC-OECD nor the methodology suggested here applies to estimation of trace gas emissions from the processing of biomass to upgraded fuels. They must be estimated separately. The Group also discussed technical options for controlling methane emissions from biomass. 12 refs

  8. Potential local use of natural gas or LNG from Hammerfest LNG plant

    International Nuclear Information System (INIS)

    Neeraas, Bengt Olav

    1999-01-01

    A base-load LNG plant is planned to be built in Norway, near by the northern most city in the world, Hammerfest. Natural gas from the Snoehvit-field will be transported by pipeline to Melkoeya, a few kilometres from Hammerfest, where the liquefaction plant is planned to be located. SINTEF Energy Research has performed a study in co-operation with the local authorities on potentials for the use of LNG and natural gas locally in the Hammerfest region. Combined power and heat production by lean-burn gas engine, low temperature freezing of high quality products by use of LNG cold and drying of fish products are some of the identified fields for the use of natural gas and LNG. The establishment of an industrial area, with fish processing industry and a central freezing storage near by Hammerfest has been suggested. The gas may be transported locally either as LNG, by tank lorry or container, or as gas in a small pipeline, depending on distance, amount and the actual use. (author)

  9. Making of a burn unit: SOA burn center

    Directory of Open Access Journals (Sweden)

    Jayant Kumar Dash

    2016-01-01

    Full Text Available Each year in India, burn injuries account for more than 6 million hospital emergency department visits; of which many require hospitalization and are referred to specialized burn centers. There are few burn surgeons and very few burn centers in India. In our state, Odisha, there are only two burn centers to cater to more than 5000 burn victims per year. This article is an attempt to share the knowledge that I acquired while setting up a new burn unit in a private medical college of Odisha.

  10. Lean Accounting - An Ingenious Solution for Cost Optimization

    OpenAIRE

    Dimi Ofileanu; Dan Ioan Topor

    2014-01-01

    The aim of this work is to present a new concept in accounting management: Lean Accounting. This work explains the way the lean concept was born; its benefits for the production system of the factories and the necessity of applying lean accounting in the factories which have implemented lean production, taking into account both its advantages and the boundaries of the other cost management methods in those factories.

  11. TH-C-9A-01: Lean Tools and Methods

    International Nuclear Information System (INIS)

    Rangaraj, D; Chan, K; Boddu, S; Pawlicki, T; Dieterich, S

    2014-01-01

    Lean thinking has revolutionized the manufacturing industry. Toyota has pioneered and leveraged this aspect of Lean thinking. Application of Lean thinking and Lean Six Sigma techniques into Healthcare and in particular in Radiation Oncology has its merits and challenges. To improve quality, safety and patient satisfaction with available resources or reducing cost in terms of time, staff and resources is demands of today's healthcare. Radiation oncology treatment involves many processes and steps, identifying and removing the non-value added steps in a process can significantly improve the efficiency. Real projects undertaken in radiation oncology department in cutting down the procedure time for MRI guided brachytherapy to 40% less using lean thinking will be narrated. Simple Lean tools and techniques such as Gemba walk, visual control, daily huddles, standard work, value stream mapping, error-proofing, etc. can be applied with existing resources and how that improved the operation in a Radiation Oncology department's two year experience will be discussed. Lean thinking focuses on identifying and solving the root-cause of a problem by asking “Why” and not “Who” and this requires a culture change of no blame. Role of leadership in building lean culture, employee empowerment and trains and develops lean thinkers will be presented. Why Lean initiatives fail and how to implement lean successfully in your clinic will be discussed. Learning Objectives: Concepts of lean management or lean thinking. Lean tools and techniques applied in Radiation Oncology. Implement no blame culture and focus on system and processes. Leadership role in implementing lean culture. Challenges for Lean thinking in healthcare

  12. Investigating employee resistance to Lean transformation: UK case study.

    OpenAIRE

    Bruce, J.; Scott, Philip; Roberts, Martyn

    2011-01-01

    Lean is a business process transformation approach that eliminates ‘wastes’ – activities that generate no value for the customer. Lean originated from the production line but is widely implemented in the service sector. This study investigates human and social factors in a Lean transformation in a ‘knowledge worker’ environment. We identify a paradox: a successful Lean programme in the service sector develops staff who are educated and empowered and thus potential opponents to future business...

  13. TH-C-9A-01: Lean Tools and Methods

    Energy Technology Data Exchange (ETDEWEB)

    Rangaraj, D [Baylor Scott and White Health, Temple, TX (United States); Chan, K [Princess Margaret Hospital, Toronto (Canada); Boddu, S [Temple, TX (United States); Pawlicki, T [UC San Diego, La Jolla, CA (United States); Dieterich, S [UC Davis Medical Center, Sacramento, CA (United States)

    2014-06-15

    Lean thinking has revolutionized the manufacturing industry. Toyota has pioneered and leveraged this aspect of Lean thinking. Application of Lean thinking and Lean Six Sigma techniques into Healthcare and in particular in Radiation Oncology has its merits and challenges. To improve quality, safety and patient satisfaction with available resources or reducing cost in terms of time, staff and resources is demands of today's healthcare. Radiation oncology treatment involves many processes and steps, identifying and removing the non-value added steps in a process can significantly improve the efficiency. Real projects undertaken in radiation oncology department in cutting down the procedure time for MRI guided brachytherapy to 40% less using lean thinking will be narrated. Simple Lean tools and techniques such as Gemba walk, visual control, daily huddles, standard work, value stream mapping, error-proofing, etc. can be applied with existing resources and how that improved the operation in a Radiation Oncology department's two year experience will be discussed. Lean thinking focuses on identifying and solving the root-cause of a problem by asking “Why” and not “Who” and this requires a culture change of no blame. Role of leadership in building lean culture, employee empowerment and trains and develops lean thinkers will be presented. Why Lean initiatives fail and how to implement lean successfully in your clinic will be discussed. Learning Objectives: Concepts of lean management or lean thinking. Lean tools and techniques applied in Radiation Oncology. Implement no blame culture and focus on system and processes. Leadership role in implementing lean culture. Challenges for Lean thinking in healthcare.

  14. Lean management in a non-manufacturing organization

    Directory of Open Access Journals (Sweden)

    Mladen Žvorc

    2013-12-01

    Full Text Available This paper examines the possibilities of a lean approach to non-manufacturing functions, i.e. a market-oriented organization. This refers to purchasing, shipment, storage, sale and delivery of goods; marketing, etc. A lean approach to business operations is discussed and several lean business methods are developed on the basis of which lean management can be used not only in manufacturing, but also in non-manufacturing organizations.

  15. Crude oil burning mechanisms

    DEFF Research Database (Denmark)

    van Gelderen, Laurens; Malmquist, L.M.V.; Jomaas, Grunde

    2015-01-01

    In order to improve predictions for the burning efficiency and the residue composition of in-situ burning of crude oil, the burning mechanism of crude oil was studied in relation to the composition of its hydrocarbon mixture, before, during and after the burning. The surface temperature, flame...... height, mass loss rate and residues of three hydrocarbon liquids (n-octane, dodecane and hexadecane), two crude oils (DUC and REBCO) and one hydrocarbon liquid mixture of the aforementioned hydrocarbon liquids were studied using the Crude Oil Flammability Apparatus. The experimental results were compared...... on the highest achievable oil slick temperature. Based on this mechanism, predictions can then be made depending on the hydrocarbon composition of the fuel and the measured surface temperature....

  16. American Burn Association

    Science.gov (United States)

    ... burn-related care, prevention, education, and research. Our multidisciplinary membership enhances our ability to work toward common goals with other organizations and educational programs. Membership Being a member of ...

  17. New Fashioned Book Burning.

    Science.gov (United States)

    Gardner, Robert

    1997-01-01

    Reports on results of a teacher's experiment in book burning as a lesson accompanying the teaching of Ray Bradbury's "Fahrenheit 451." Discusses student reactions and the purpose of or justification for the experimental lesson. (TB)

  18. Effect of selection for lean growth on gonadal development of ...

    African Journals Online (AJOL)

    A primary objective of commercial pig production is lean meat yield in order to satisfy consumer needs. The majority of the commercial pig breeds in South Africa have been selected for high lean growth potential and reduced backfat thickness. There are indications that selection for high lean meat yield may affect the ...

  19. Using Simulation to Explore Lean Manufacturing Implementation Strategies

    Science.gov (United States)

    Shannon, Patrick W.; Krumwiede, Kip R.; Street, Jeffrey N.

    2010-01-01

    Lean manufacturing, an outgrowth of the Toyota Production System, has spread far beyond the automobile industry and is seen by many leaders as a key management philosophy in the battle to compete on an international scale. Successful implementation of lean requires that managers and employees be educated in the proper application of lean tools and…

  20. Når lean organiserer på hospitalet

    DEFF Research Database (Denmark)

    Hauge, Amalie Martinus

    Lean er kendt og anvendt af mange offentlige organisationer i Danmark. Selv om Leans anvendelighed de fleste steder er slået fast, bliver Lean imidlertid ved med at udfordre og skabe konflikt. Hvorfor det? Dette spørgsmål – og mange andre – bliver belyst i denne rapport, som er baseret på en Ph...

  1. Reducing waste in administrative services with lean principles

    NARCIS (Netherlands)

    Wijnhoven, Alphonsus B.J.M.; Beckers, David; Amrit, Chintan Amrit

    2016-01-01

    In the last few decades, lean techniques have been developed for removing with waste in manufacturing. More recently, lean is used outside the manufacturing context as well. This article focuses on using lean thinking for reducing waste in administrative services, i.e., business services with

  2. Teaching Special Decisions in a Lean Accounting Environment

    Science.gov (United States)

    Haskin, Daniel

    2010-01-01

    Lean accounting has become increasingly important as more and more companies adopt the lean enterprise model or some variation of it. Cost and managerial accounting textbooks continue to use, almost exclusively, models based on standard overhead absorption, which if used in a lean environment will not accurately reflect the benefits from the…

  3. Application of lean thinking to health care: issues and observations

    Science.gov (United States)

    Joosten, Tom; Bongers, Inge; Janssen, Richard

    2009-01-01

    Background Incidents and quality problems are a prime cause why health care leaders are calling to redesign health care delivery. One of the concepts used is lean thinking. Yet, lean often leads to resistance. Also, there is a lack of high quality evidence supporting lean premises. In this paper, we present an overview of lean thinking and its application to health care. Development, theory and application of lean thinking to health care Lean thinking evolved from a tool designed to improve operational shop-floor performance at an automotive manufacturer to a management approach with both operational and sociotechnical aspects. Sociotechnical dynamics have until recently not received much attention. At the same time a balanced approach might lead to a situation where operational and sociotechnial improvements are mutually reinforcing. Application to health care has been limited and focussed mainly on operational aspects using original lean tools. A more integrative approach would be to pay more attention to sociotechnical dynamics of lean implementation efforts. Also, the need to use the original lean tools may be limited, because health care may have different instruments and tools already in use that are in line with lean thinking principles. Discussion We believe lean thinking has the potential to improve health care delivery. At the same time, there are methodological and practical considerations that need to be taken into account. Otherwise, lean implementation will be superficial and fail, adding to existing resistance and making it more difficult to improve health care in the long term. PMID:19696048

  4. Lean-team effectiveness through leader values and members’ informing

    NARCIS (Netherlands)

    van Dun, Desirée Hermina; Wilderom, Celeste P.M.

    2016-01-01

    Purpose Although empirical tests of effective lean-team leadership are scarce, leaders are often blamed when lean work-floor initiatives fail. In the present study, a lean-team leader’s work values are assumed to affect his or her team members’ behaviors and, through them, to attain team

  5. Cull sow knife-separable lean content evaluation at harvest and lean mass content prediction equation development.

    Science.gov (United States)

    Abell, Caitlyn E; Stalder, Kenneth J; Hendricks, Haven B; Fitzgerald, Robert F

    2012-07-01

    The objectives of this study were to develop a prediction equation for carcass knife-separable lean within and across USDA cull sow market weight classes (MWC) and to determine carcass and individual primal cut knife separable lean content from cull sows. There were significant percent lean and fat differences in the primal cuts across USDA MWC. The two lighter USDA MWC had a greater percent carcass lean and lower percent fat compared to the two heavier MWC. In general, hot carcass weight explained the majority of carcass lean variation. Additionally, backfat was a significant variation source when predicting cull sow carcass lean. The findings support using a single lean prediction equation across MWC to assist processors when making cull sow purchasing decisions and determine the mix of animals from various USDA MWC that will meet their needs when making pork products with defined lean:fat content. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Burn-out

    OpenAIRE

    Patricia van Echtelt

    2014-01-01

    Deze publicatie is alleen elektronisch verkrijgbaar (downloaden van deze site) Burn-out (ofwel: emotionele uitputting) komt relatief vaak voor: ongeveer één op de acht werknemers in Nederland heeft er last van. Het wordt dan ook gezien als een serieus maatschappelijk probleem dat beleidsmatig aandacht vergt. Dit rapport presenteert de resultaten van twee specifieke analyses over burn-out. Ten eerste gaan we na wat het effect is van emotionele uitputting op de loopbaan van werknemers. Ten twee...

  7. Smartphone applications in burns.

    Science.gov (United States)

    Wurzer, Paul; Parvizi, Daryousch; Lumenta, David B; Giretzlehner, Michael; Branski, Ludwik K; Finnerty, Celeste C; Herndon, David N; Tuca, Alexandru; Rappl, Thomas; Smolle, Christian; Kamolz, Lars P

    2015-08-01

    Since the introduction of applications (apps) for smartphones, the popularity of medical apps has been rising. The aim of this review was to demonstrate the current availability of apps related to burns on Google's Android and Apple's iOS store as well as to include a review of their developers, features, and costs. A systematic online review of Google Play Store and Apple's App Store was performed by using the following search terms: "burn," "burns," "thermal," and the German word "Verbrennung." All apps that were programmed for use as medical apps for burns were included. The review was performed from 25 February until 1 March 2014. A closer look at the free and paid calculation apps including a standardized patient was performed. Four types of apps were identified: calculators, information apps, book/journal apps, and games. In Google Play Store, 31 apps were related to burns, of which 20 were calculation apps (eight for estimating the total body surface area (TBSA) and nine for total fluid requirement (TFR)). In Apple's App Store, under the category of medicine, 39 apps were related to burns, of which 21 were calculation apps (19 for estimating the TBSA and 17 for calculating the TFR). In 19 out of 32 available calculation apps, our study showed a correlation of the calculated TFR compared to our standardized patient. The review demonstrated that many apps for medical burns are available in both common app stores. Even free available calculation apps may provide a more objective and reproducible procedure compared to manual/subjective estimations, although there is still a lack of data security especially in personal data entered in calculation apps. Further clinical studies including smartphone apps for burns should be performed. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  8. Burning mouth syndrome

    OpenAIRE

    Zakrzewska, Joanna; Buchanan, John A. G.

    2016-01-01

    Burning mouth syndrome is a debilitating medical condition affecting nearly 1.3 million of Americans. Its common features include a burning painful sensation in the mouth, often associated with dysgeusia and xerostomia, despite normal salivation. Classically, symptoms are better in the morning, worsen during the day and typically subside at night. Its etiology is largely multifactorial, and associated medical conditions may include gastrointestinal, urogenital, psychiatric, neurologic and met...

  9. Burning mouth syndrome: update

    OpenAIRE

    Cassol Spanemberg, Juliana; Rodríguez de Rivera Campillo, Ma Eugenia; Jané Salas, Enric; López López, José, 1958-

    2014-01-01

    Burning Mouth Syndrome (BMS) is a chronic disorder that predominately affects middle-aged women in the postmenopausal period. The condition is distinguished by burning symptoms of the oral mucosa and the absence of any clinical signs. The etiology of BMS is complex and it includes a variety of factors. Local, systemic and psychological factors such as stress, anxiety and depression are listed among the possible causes of BMS. BMS may sometimes be classified as BMS Type I, II or III. Although ...

  10. Burning mouth syndrome

    OpenAIRE

    Jimson, Sudha; Rajesh, E.; Krupaa, R. Jayasri; Kasthuri, M.

    2015-01-01

    Burning mouth syndrome (BMS) is a complex disorder that is characterized by warm or burning sensation in the oral mucosa without changes on physical examination. It occurs more commonly in middle-aged and elderly women and often affects the tip of the tongue, lateral borders, lips, hard and soft palate. This condition is probably of multi-factorial origin, often idiopathic, and its etiopathogensis is unknown. BMS can be classified into two clinical forms namely primary and secondary BMS. As a...

  11. Lean Transformation Guidance: Why Organizations Fail To Achieve and Sustain Excellence Through Lean Improvement

    Directory of Open Access Journals (Sweden)

    Mohammed Hamed Ahmed

    2013-06-01

    Full Text Available Many companies are complaining that lean didn’t achieve their long-term goals, and the improvement impact was very short-lived. 7 out of each 10 lean projects fail as companies try to use lean like a toolkit, copying and pasting the techniques without trying to adapt the employee’s culture, manage the improvement process, sustain the results, and develop their leaders. When the Toyota production system was created, the main goal was to remove wastes from the shop floor using some lean techniques and tools. What was not clear is that this required from Toyota a long process of leadership development, and a high commitment to training and coaching their employee. A Failure to achieve and sustain the improvement is a problem of both management and leadership as well as the improper understanding of the human behavior, and the required culture to success.

  12. Systems Thinking, Lean Production and Action Learning

    Science.gov (United States)

    Seddon, John; Caulkin, Simon

    2007-01-01

    Systems thinking underpins "lean" management and is best understood through action-learning as the ideas are counter-intuitive. The Toyota Production System is just that--a system; the failure to appreciate that starting-place and the advocacy of "tools" leads many to fail to grasp what is, without doubt, a significant…

  13. Lean leiderschap voor (nog) betere teamprestaties

    NARCIS (Netherlands)

    van Dun, Desirée Hermina; Wilderom, Celeste P.M.

    2016-01-01

    Veel managers en teams hebben moeite om continu te blijven verbeteren. Recent onderzoek van de Universiteit Twente laat zien dat er bij het toepassen van lean meer aandacht nodig is voor gedragsontwikkeling van zowel medewerkers als leidinggevenden. Managers met bepaalde gedragskenmerken creëren een

  14. Ares Launch Vehicles Lean Practices Case Study

    Science.gov (United States)

    Doreswamy, Rajiv; Self, Timothy A.

    2007-01-01

    The Ares launch vehicles team, managed by the Ares Projects Office (APO) at NASA Marshall Space Flight Center, has completed the Ares I Crew Launch Vehicle System Requirements Review and System Definition Review and early design work for the Ares V Cargo Launch Vehicle. This paper provides examples of how Lean Manufacturing, Kaizen events, and Six Sigma practices are helping APO deliver a new space transportation capability on time and within budget, while still meeting stringent technical requirements. For example, Lean philosophies have been applied to numerous process definition efforts and existing process improvement activities, including the Ares I-X test flight Certificate of Flight Readiness (CoFR) process, risk management process, and review board organization and processes. Ares executives learned Lean practices firsthand, making the team "smart buyers" during proposal reviews and instilling the team with a sense of what is meant by "value-added" activities. Since the goal of the APO is to field launch vehicles at a reasonable cost and on an ambitious schedule, adopting Lean philosophies and practices will be crucial to the Ares Project's long-term SUCCESS.

  15. Lean Six Sigma: Stap voor stap

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Koning, H.; de Mast, J.

    2008-01-01

    Lean Six Sigma is de culminatie van ontwikkelingen in kwaliteitsverbetering in de 20ste eeuw. Het combineert belangrijke principes en technieken in een goed gestructureerde en geïntegreerde benadering. Het belichaamt wetenschappelijke inzichten over onderzoeksmethodologie, management en economie. In

  16. Lean leadership and change management skills

    NARCIS (Netherlands)

    Frank Willems

    2013-01-01

    Gastcollege Masteropleiding MIM Tilburg University/TiasNimbas Business School op 17 & 18 mei 2013. • Basic principles of Change Management • Group practice • TheoryU and Social Networking theory as framework for Leadership • Theory about Lean thinking as a method for improving Leadership skills and

  17. Lean approaches in a knowledge worker environment

    CSIR Research Space (South Africa)

    Christelis, L

    2012-08-01

    Full Text Available Most of us are familiar with the concept of Lean (a way to do more and more with less and less). The principles have been applied by the Japanese as part of the Toyota Production System from as early as the 1950's. Subsequently many have applied...

  18. Lean and Agile: An Epistemological Reflection

    Science.gov (United States)

    Browaeys, Marie-Joelle; Fisser, Sandra

    2012-01-01

    Purpose: The aim of the paper is to contribute to the discussion of treating the concepts of lean and agile in isolation or combination by presenting an alternative view from complexity thinking on these concepts, considering an epistemological approach to this topic. Design/methodology/approach: The paper adopts an epistemological approach, using…

  19. Implementing Lean Six Sigma in organizations

    NARCIS (Netherlands)

    Lameijer, B.A.

    2017-01-01

    This thesis focuses on operational excellence following the Lean Six Sigma (LSS) method. As the popularity of implementing LSS grows, questions about implementing LSS in organizations arise, and this is where we aim to contribute. We study key questions about implementing LSS in organizations at two

  20. Modelling green and lean supply chains

    DEFF Research Database (Denmark)

    Govindan, Kannan; Carvalho, Helena; Azevedo, Susana G.

    2017-01-01

    This manuscript proposes a model to support decision making and to help managers identify the best set of green and lean supply chain management practices to improve their eco-efficiency. To attain this objective, a mathematical model based on eco-efficiency concepts is suggested to overcome...... a strategic framework to support the design of eco-efficient supply chains....

  1. Implementing lean in a surgical ward

    DEFF Research Database (Denmark)

    Edwards, Kasper; Nielsen, Anders Paarup; Jacobsen, Peter

    be planned (in detail) in advance. The remaining operating rooms are allocated to this flow and there have been no significant changes to the organization of work in these theaters. Lean management is derived from the Toyota production system and is a comprehensive system of tools and techniques...

  2. Performance management practices in lean manufacturing organizations

    NARCIS (Netherlands)

    Bellisario, Andrea; Pavlov, Andrey

    2018-01-01

    This paper provides the first systematic look into the existing research on performance management (PM) practices employed in lean manufacturing organisations (LMOs). It adopts a systematic review method to examine the evidence generated in the period 2004 – 2015 and uses a comprehensive PM

  3. Lean planning and control : principles and practice

    NARCIS (Netherlands)

    Riezebos, Jan; Suer, Gursel; Gen, Mitsuo

    2018-01-01

    A basic characteristic of lean, agile, and responsive production systems are the use of teams instead of functional departments. Another characteristic is the use of rather simple shop floor control methods to manage the flow of orders. The shop floor control methods provide robust and visual

  4. Personality characteristics of excellent lean managers

    DEFF Research Database (Denmark)

    Steendahl Nielsen, Jacob; Boer, Harry; Lindgren, Peter

    2016-01-01

    Today many Danish companies are implementing Lean and hereby trying to implement a continuous improvement (CI) program and culture. We have observed that companies can easily implement the artifacts of CI, such as Kaizen boards, Kaizen meetings, Performance management (KPI), A3 and PDCA reports...

  5. Lowlands sociotechnical design theory and lean production

    NARCIS (Netherlands)

    Christis, Jac; Soepenberg, Erik; Mohr, Bernard J.; van Amelsvoort, Pierre

    2015-01-01

    Lean Production (LP) can be regarded as a design approach in search of a theoretical foundation. In this paper we show that Lowlands’ Sociotechnical Design Theory (STSL) could function as such a foundation. To reach this goal, we first describe STSL as a system theoretical reformulation of Original

  6. Measuring lean implementation for maintenance service companies

    NARCIS (Netherlands)

    de Jong, Stephan J.; Beelaerts van Blokland, W.W.A.

    2016-01-01

    Purpose – Implementation of lean manufacturing is currently performed in the production industry; however, for the airline maintenance service industry, it is still in its infancy. Indicators such as work in process, cycle time, on-time performance and inventory are useful indicators to measure

  7. The Scientific Underpinning of Lean Six Sigma

    NARCIS (Netherlands)

    Does, R.J.M.M.; de Mast, J.; de Koning, H.; Bisgaard, S.

    2007-01-01

    The twentieth century saw an incredible development of professional organizations. The impact of technological advances is obvious, but besides these, innovations in management structures and methods have resulted in the highly productive organizations of today. Lean Six Sigma is not revolutionary.

  8. Lean Six Sigma for Service and Healthcare

    NARCIS (Netherlands)

    de Mast, J.; Does, R.J.M.M.; de Koning, H.

    2006-01-01

    Lean Six Sigma is built on principles and methods that have proven themselves over the twentieth century. It has incorporated the most effective approaches and integrated them into a full programme. It offers a management structure for organizing continuous improvement of routine tasks, such as

  9. Lean Sygehuset - del I: En patienthistorie

    DEFF Research Database (Denmark)

    Laursen, Martin Lindgaard; Gertsen, Frank

    Denne forskningsrapport introducerer et forskningsprojekt baseret på case studier af Lean principper anvendt på Skejby sygehus. Operationelle udfordringer i sygehusets arbejdsgange illustreres gennem et observeret patientforløb. Disse udfordringer, et oprids af sygehusenes vilkår, og gennemgang af...

  10. Radial lean direct injection burner

    Science.gov (United States)

    Khan, Abdul Rafey; Kraemer, Gilbert Otto; Stevenson, Christian Xavier

    2012-09-04

    A burner for use in a gas turbine engine includes a burner tube having an inlet end and an outlet end; a plurality of air passages extending axially in the burner tube configured to convey air flows from the inlet end to the outlet end; a plurality of fuel passages extending axially along the burner tube and spaced around the plurality of air passage configured to convey fuel from the inlet end to the outlet end; and a radial air swirler provided at the outlet end configured to direct the air flows radially toward the outlet end and impart swirl to the air flows. The radial air swirler includes a plurality of vanes to direct and swirl the air flows and an end plate. The end plate includes a plurality of fuel injection holes to inject the fuel radially into the swirling air flows. A method of mixing air and fuel in a burner of a gas turbine is also provided. The burner includes a burner tube including an inlet end, an outlet end, a plurality of axial air passages, and a plurality of axial fuel passages. The method includes introducing an air flow into the air passages at the inlet end; introducing a fuel into fuel passages; swirling the air flow at the outlet end; and radially injecting the fuel into the swirling air flow.

  11. Lean automation development : applying lean principles to the automation development process

    OpenAIRE

    Granlund, Anna; Wiktorsson, Magnus; Grahn, Sten; Friedler, Niklas

    2014-01-01

    By a broad empirical study it is indicated that automation development show potential of improvement. In the paper, 13 lean product development principles are contrasted to the automation development process and it is suggested why and how these principles can facilitate, support and improve the automation development process. The paper summarises a description of what characterises a lean automation development process and what consequences it entails. Main differences compared to current pr...

  12. Leveraging lean in the office: Lean office needs a novel and differentiated approach

    OpenAIRE

    Rüttimann, Bruno G.; Fischer, Urs P.; Stöckli, Martin T.

    2014-01-01

    Lean Six Sigma tools have been increasingly employed also in the service industry, however with different success as field studies have shown. The reason not only has to be attributed to a poor Change Management, but can also be attributed to the intrinsic characteristics of the Lean techniques, which have been tailored to sustain a stable customer-takted pull-manufacturing principle. An office workplace shows significant differences to a procedural shop floor environment, as it comprises bot...

  13. Combustion Dynamics and Control for Ultra Low Emissions in Aircraft Gas-Turbine Engines

    Science.gov (United States)

    DeLaat, John C.

    2011-01-01

    Future aircraft engines must provide ultra-low emissions and high efficiency at low cost while maintaining the reliability and operability of present day engines. The demands for increased performance and decreased emissions have resulted in advanced combustor designs that are critically dependent on efficient fuel/air mixing and lean operation. However, all combustors, but most notably lean-burning low-emissions combustors, are susceptible to combustion instabilities. These instabilities are typically caused by the interaction of the fluctuating heat release of the combustion process with naturally occurring acoustic resonances. These interactions can produce large pressure oscillations within the combustor and can reduce component life and potentially lead to premature mechanical failures. Active Combustion Control which consists of feedback-based control of the fuel-air mixing process can provide an approach to achieving acceptable combustor dynamic behavior while minimizing emissions, and thus can provide flexibility during the combustor design process. The NASA Glenn Active Combustion Control Technology activity aims to demonstrate active control in a realistic environment relevant to aircraft engines by providing experiments tied to aircraft gas turbine combustors. The intent is to allow the technology maturity of active combustion control to advance to eventual demonstration in an engine environment. Work at NASA Glenn has shown that active combustion control, utilizing advanced algorithms working through high frequency fuel actuation, can effectively suppress instabilities in a combustor which emulates the instabilities found in an aircraft gas turbine engine. Current efforts are aimed at extending these active control technologies to advanced ultra-low-emissions combustors such as those employing multi-point lean direct injection.

  14. TOWARDS GREEN THROUGH LEAN/LEAN SIX SIGMA APPROACHES: A LITERATURE REVIEW AT SERVICE INDUSTRY

    Directory of Open Access Journals (Sweden)

    RODRIGO GOYANNES GUSMÃO CAIADO

    2017-08-01

    Full Text Available In the last decades, sustainable development have increasingly gained importance to service industry and lean/Six Sigma approaches are becoming more and more outstanding in order to improve sustainability performance. In the post-modern era the integration between those approaches are necessary in order to aid organisations to balance the need for operational efficiency in their production and service systems with environmental commitment and social fairness. Because of that, Lean Six Sigma practices are progressively becoming widespread in studies about service, as way to improve quality, efficiency, effectiveness and sustainability of services. The purpose of this paper is to critically review the Lean and Lean Six Sigma (L6σ methodologies and highlight their importance to achieve sustainable development in service industry. To do this, a systematic literature review (SLR of the subjects under investigation was conducted. We examine the compatibility and divergences of the green, lean and Six Sigma concepts and implications regarding its sustainable implementation in service industry. The study has two major contributions. First, it is one of the first researches that investigate the potential benefits of integrating green, lean and Six Sigma in service sector. Second, it supports and expands current literature, providing both academicians and practitioners a better panorama to understand the present status of L6σ for achieving sustainability in service sector.

  15. Intermittent hypoxia induces hyperlipidemia in lean mice.

    Science.gov (United States)

    Li, Jianguo; Thorne, Laura N; Punjabi, Naresh M; Sun, Cheuk-Kwan; Schwartz, Alan R; Smith, Philip L; Marino, Rafael L; Rodriguez, Annabelle; Hubbard, Walter C; O'Donnell, Christopher P; Polotsky, Vsevolod Y

    2005-09-30

    Obstructive sleep apnea, a syndrome leading to recurrent intermittent hypoxia (IH), has been associated previously with hypercholesterolemia, independent of underlying obesity. We examined the effects of experimentally induced IH on serum lipid levels and pathways of lipid metabolism in the absence and presence of obesity. Lean C57BL/6J mice and leptin-deficient obese C57BL/6J-Lep(ob) mice were exposed to IH for five days to determine changes in serum lipid profile, liver lipid content, and expression of key hepatic genes of lipid metabolism. In lean mice, exposure to IH increased fasting serum levels of total cholesterol, high-density lipoprotein (HDL) cholesterol, phospholipids (PLs), and triglycerides (TGs), as well as liver TG content. These changes were not observed in obese mice, which had hyperlipidemia and fatty liver at baseline. In lean mice, IH increased sterol regulatory element binding protein 1 (SREBP-1) levels in the liver, increased mRNA and protein levels of stearoyl-coenzyme A desaturase 1 (SCD-1), an important gene of TG and PL biosynthesis controlled by SREBP-1, and increased monounsaturated fatty acid content in serum, which indicated augmented SCD-1 activity. In addition, in lean mice, IH decreased protein levels of scavenger receptor B1, regulating uptake of cholesterol esters and HDL by the liver. We conclude that exposure to IH for five days increases serum cholesterol and PL levels, upregulates pathways of TG and PL biosynthesis, and inhibits pathways of cholesterol uptake in the liver in the lean state but does not exacerbate the pre-existing hyperlipidemia and metabolic disturbances in leptin-deficient obesity.

  16. Study on laminar burning velocity of syngas-air premixed flames in various mixing conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kee Man; Jeong, Byeong Gyu [Sunchon National University, Suncheon (Korea, Republic of); Lee, Seung Ro [Chonbuk National University, Jeonju (Korea, Republic of)

    2015-07-15

    The laminar burning velocity of syngas-air premixed flames was measured with various equivalence ratios from 0.5 to 5.0 and a mole fraction of H{sub 2} from 0.05 to 0.75. The laminar burning velocity was experimentally determined using a Bunsen flame according to the cone angle and surface area methods. A premixed code with a USC-II detailed reaction mechanism was used for the numerical calculations to predict the laminar burning velocity and to examine the relationship between the burning velocity enhancement and the hydrogen-related reactions. The results indicate that an appropriate method for the measurement of laminar burning velocity is necessary in the H{sub 2}/CO/air syngas premixed flame. In addition, the burning velocity linearly increased with the increase of the H{sub 2} mole fraction in the syngas mixture, although the burning velocity of H{sub 2} was 10 times larger than that of CO. This result is attributed to the rapid production of H-radicals at the early stage of combustion. Furthermore, the predicted mole fractions of H and OH radicals increased with the increase of H{sub 2} mole fraction for a lean syngas mixture. However, the mole fraction of OH radicals, an indicator of heat release rate, decreased for rich syngas mixture, resulting in a reduction of the laminar burning velocity, even with an increase of the H{sub 2} mole fraction.

  17. Study on laminar burning velocity of syngas-air premixed flames in various mixing conditions

    International Nuclear Information System (INIS)

    Lee, Kee Man; Jeong, Byeong Gyu; Lee, Seung Ro

    2015-01-01

    The laminar burning velocity of syngas-air premixed flames was measured with various equivalence ratios from 0.5 to 5.0 and a mole fraction of H 2 from 0.05 to 0.75. The laminar burning velocity was experimentally determined using a Bunsen flame according to the cone angle and surface area methods. A premixed code with a USC-II detailed reaction mechanism was used for the numerical calculations to predict the laminar burning velocity and to examine the relationship between the burning velocity enhancement and the hydrogen-related reactions. The results indicate that an appropriate method for the measurement of laminar burning velocity is necessary in the H 2 /CO/air syngas premixed flame. In addition, the burning velocity linearly increased with the increase of the H 2 mole fraction in the syngas mixture, although the burning velocity of H 2 was 10 times larger than that of CO. This result is attributed to the rapid production of H-radicals at the early stage of combustion. Furthermore, the predicted mole fractions of H and OH radicals increased with the increase of H 2 mole fraction for a lean syngas mixture. However, the mole fraction of OH radicals, an indicator of heat release rate, decreased for rich syngas mixture, resulting in a reduction of the laminar burning velocity, even with an increase of the H 2 mole fraction.

  18. Six sigma and lean production adoption in a manufacturing company

    Directory of Open Access Journals (Sweden)

    Alisson Christian Scheller

    2014-11-01

    Full Text Available The connection among Lean Production with Six Sigma originated the Lean Six Sigma methodology, focused on processes variation and waste reduction. This methodology was developed on different ways in the companies and there is no consensus over its structure and its implementation. In this context, this paper aims to identify and analyze the main characteristics on the adoption and integration of Lean Six Sigma methodology through a case study conducted in a manufacturing company that adopts lean production and six sigma. The results show two important aspects of the Lean Six Sigma methodology. One of them is the adoption of the value stream mapping as a central tool on Lean Six Sigma. The other is the use of DMAIC for improvements actions. The study indicates that despite the difficulties on Lean Six Sigma implementation, the methodology offers benefits to the company that adopts it in the suitable way.

  19. The Hybrid Lean System to Improve Manufacturing Environment

    Directory of Open Access Journals (Sweden)

    Ahmad Ahmad Nur Aizat

    2017-01-01

    Full Text Available Lean manufacturing is a systematic approch could increase manufacturing competitiveness by identifying and elminating waste through lean tools. However, these tools are often categorized into different groups, continues to be difficult for companies to select the most appropriate lean tool to be adopted, especially in respect of the SMEs whose knowledge of lean tools and associated principles are limited. This study is to propose solution on how to implement appropriate lean tools in food manufacturing industry located at Rengit, Johor. Qualitative method is used as a methodology to see the changes after the implementation of lean tools. Interview session also a part of method to collect data from respondents. The finding from this paper shows that implementation of an appropriate lean tool will help to eliminate waste in industry sector, maintain and control the inventory, improve quality of the product and improve overall operational process.

  20. Tritium burning in inertial electrostatic confinement fusion facility

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Masami, E-mail: onishi@kansai-u.ac.jp [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Yamamoto, Yasushi; Osawa, Hodaka [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Hatano, Yuji; Torikai, Yuji [Hydrogen Isotope Science Center, University of Toyama, Gofuku, Toyama 930-8555 (Japan); Murata, Isao [Faculty of Engineering Environment and Energy Department, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kamakura, Keita; Onishi, Masaaki; Miyamoto, Keiji; Konda, Hiroki [Department of Science and Engineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680 (Japan); Masuda, Kai [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Hotta, Eiki [Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259 Nagatsuda-cho, Midori-ku, Yokohama 226-8503 (Japan)

    2016-11-01

    Highlights: • An experiment on tritium burning is conducted in an inertial electrostatic confinement fusion (IECF) facility. • A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used. • The neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. • The neutron production rate of the D–T gas mixture in 1:1 ratio is expected to be more than 10{sup 8}(1/sec) in the present D–T experiment. - Abstract: An experiment on tritium burning is conducted to investigate the enhancement in the neutron production rate in an inertial electrostatic confinement fusion (IECF) facility. The facility is designed such that it is shielded from the outside for safety against tritium and a getter pump is used for evacuating the vacuum chamber and feeding the fuel gas. A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used, and its neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. Moreover, the results show good agreement with those of a simplified theoretical estimation of the neutron production rate. After tritium burning, the exhausted fuel gas undergoes a tritium recovery procedure through a water bubbler device. The amount of gaseous tritium released by the developed IECF facility after tritium burning is verified to be much less than the threshold set by regulations.

  1. Tritium burning in inertial electrostatic confinement fusion facility

    International Nuclear Information System (INIS)

    Ohnishi, Masami; Yamamoto, Yasushi; Osawa, Hodaka; Hatano, Yuji; Torikai, Yuji; Murata, Isao; Kamakura, Keita; Onishi, Masaaki; Miyamoto, Keiji; Konda, Hiroki; Masuda, Kai; Hotta, Eiki

    2016-01-01

    Highlights: • An experiment on tritium burning is conducted in an inertial electrostatic confinement fusion (IECF) facility. • A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used. • The neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. • The neutron production rate of the D–T gas mixture in 1:1 ratio is expected to be more than 10"8(1/sec) in the present D–T experiment. - Abstract: An experiment on tritium burning is conducted to investigate the enhancement in the neutron production rate in an inertial electrostatic confinement fusion (IECF) facility. The facility is designed such that it is shielded from the outside for safety against tritium and a getter pump is used for evacuating the vacuum chamber and feeding the fuel gas. A deuterium–tritium gas mixture with 93% deuterium and 7% tritium is used, and its neutron production rate is measured to be 5–8 times more than that of pure deuterium gas. Moreover, the results show good agreement with those of a simplified theoretical estimation of the neutron production rate. After tritium burning, the exhausted fuel gas undergoes a tritium recovery procedure through a water bubbler device. The amount of gaseous tritium released by the developed IECF facility after tritium burning is verified to be much less than the threshold set by regulations.

  2. Burning mouth disorder

    Directory of Open Access Journals (Sweden)

    Anand Bala

    2012-01-01

    Full Text Available Burning mouth disorder (BMD is a burning or stinging sensation affecting the oral mucosa, lips and/or tongue, in the absence of clinically visible mucosal lesions. There is a strong female predilection, with the age of onset being approximately 50 years. Affected patients often present with multiple oral complaints, including burning, dryness and taste alterations. The causes of BMD are multifactorial and remain poorly understood. Recently, there has been a resurgence of interest in this disorder with the discovery that the pain of burning mouth syndrome (BMS may be neuropathic in origin and originate both centrally and peripherally. The most common sites of burning are the anterior tongue, anterior hard palate and lower lip, but the distribution of oral sites affected does not appear to affect the natural history of the disorder or the response to treatment BMS may persist for many years. This article provides updated information on BMS and presents a new model, based on taste dysfunction, for its pathogenesis.

  3. Developing A Strategy to Enact Lean

    Directory of Open Access Journals (Sweden)

    Nicola Morrey

    2013-01-01

    Full Text Available This paper explains the strategy employed by a case study company to implement lean across the business, and to reflect on the success of this approach so other companies may consider this learning and how it might be useful to them. The strategy to enact lean in the case study company was based on creating a number of standard tools/ways of working. These tools can be considered to be standardised work for key aspects of the construction process that the company undertakes. The aim of the tools was to ensure that critical tasks would be carried out to the correct standard (quality, time, cost, health and safety every time, across the business. Achievement of this is expected to lead to improved performance and elimination of variation (waste. To implement this strategy of using standardised work to eliminate variation and lead to improved performance, a step-by-step process was developed to create the tools/standardised work. The paper describes the process that was undertaken and how it aimed to not only produce a number of tools/standardised work, but also to involve people and managers from across the business such that lean philosophy and thinking might also begin to become embedded. The paper will firstly explain, with reference to the relevant literature, how and why the strategy to implement standardised work was chosen, the process that was defined to develop the standardised work, and what happened when that process was put into practice. The findings of the paper show that whilst the completed tools delivered business benefits, the development of the tools did not follow the planned process. The paper discusses how people within the business responded to this strategy and how the process had to be continuously adapted to cope with the current business environment and path dependencies, further evidencing that lean implementations need to be tailored to suit the needs of the individual firm, rather than there being a one size fits all

  4. Análise por cromatografia gasosa de BTEX nas emissões de motor de combustão interna alimentado com diesel e mistura diesel-biodiesel (B10 Analysis of BTEX in the emissions from an internal combustion engine burning diesel oil and diesel-biodiesel mixture (B10 by gas chromatography

    Directory of Open Access Journals (Sweden)

    Sérgio L. Ferreira

    2008-01-01

    Full Text Available This paper describes the procedures for analysing pollutant gases emitted by engines, such as volatile organic compounds (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene by using high resolution gas chromatography (HRGC. For IC engine burning, in a broad sense, the use of the B10 mixture reduces drastically the emissions of aromatic compounds. Especially for benzene the reduction of concentrations occurs at the level of about 24.5%. Although a concentration value below 1 µg mL-1 has been obtained, this reduction is extremely significant since benzene is a carcinogenic compound.

  5. Methoxyphenols in smoke from biomass burning

    Energy Technology Data Exchange (ETDEWEB)

    Kjaellstrand, J

    2000-07-01

    Wood and other forest plant materials were burned in laboratory experiments with the ambition to simulate the natural burning course in a fireplace or a forest fire. Smoke samples were taken and analysed with respect to methoxyphenols, using gas chromatography and mass spectrometry. Different kinds of bio pellets, intended for residential heating were studied in the same way. The aim of a first study was to establish analytical data to facilitate further research. Thirty-six specific methoxyphenols were identified, and gas chromatographic retention and mass spectrometric data were determined for these. In a subsequent study, the methoxyphenol emissions from the burning of wood and other forest plant materials were investigated. Proportions and concentrations of specific methoxyphenols were determined. Methoxyphenols and anhydrosugars, formed from the decomposition of lignin and cellulose respectively, were the most prominent semi-volatile compounds in the biomass smoke. The methoxyphenol compositions reflected the lignin structures of different plant materials. Softwood smoke contained almost only 2-methoxyphenols, while hardwood smoke contained both 2-methoxyphenols and 2,6-dimethoxyphenols. The methoxyphenols in smoke from pellets, made of sawdust, bark and lignin, reflected the source of biomass. Although smoke from incompletely burned wood contains mainly methoxyphenols and anhydrosugars, there is also a smaller amount of well-known hazardous compounds present. The methoxyphenols are antioxidants. They appear mainly condensed on particles and are presumed to be inhaled together with other smoke components. As antioxidants, phenols interrupt free radical chain reactions and possibly counteract the effect of hazardous smoke components. Health hazards of small-scale wood burning should be re-evaluated considering antioxidant effects of the methoxyphenols.

  6. Psychiatric aspects of burn

    Directory of Open Access Journals (Sweden)

    Dalal P

    2010-10-01

    Full Text Available Burn injuries and their subsequent treatment cause one of the most excruciating forms of pain imaginable. The psychological aspects of burn injury have been researched in different parts of the world, producing different outcomes. Studies have shown that greater levels of acute pain are associated with negative long-term psychological effects such as acute stress disorder, depression, suicidal ideation, and post-traumatic stress disorder for as long as 2 years after the initial burn injury. The concept of allostatic load is presented as a potential explanation for the relationship between acute pain and subsequent psychological outcomes. A biopsychosocial model is also presented as a means of obtaining better inpatient pain management and helping to mediate this relationship.

  7. Gas Phase Nanoparticle Synthesis

    Science.gov (United States)

    Granqvist, Claes; Kish, Laszlo; Marlow, William

    This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

  8. Lean Strategies in the Operating Room.

    Science.gov (United States)

    Robinson, Stephen T; Kirsch, Jeffrey R

    2015-12-01

    Lean strategies can be readily applied to health care in general and operating rooms specifically. The emphasis is on the patient as the customer, respect and engagement of all providers, and leadership from management. The strategy of lean is to use continuous improvement to eliminate waste from the care process, leaving only value-added activities. This iterative process progressively adds the steps of identifying the 7 common forms of waste (transportation, inventory, motion, waiting, overproduction, overprocessing, and defects), 5S (sort, simplify, sweep, standardize, sustain), visual controls, just-in-time processing, level-loaded work, and built-in quality to achieve the highest quality of patient care. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Network model of project "Lean Production"

    Science.gov (United States)

    Khisamova, E. D.

    2018-05-01

    Economical production implies primarily new approaches to culture of management and organization of production and offers a set of tools and techniques that allows reducing losses significantly and making the process cheaper and faster. Economical production tools are simple solutions that allow one to see opportunities for improvement of all aspects of the business, to reduce losses significantly, to constantly improve the whole spectrum of business processes, to increase significantly the transparency and manageability of the organization, to take advantage of the potential of each employee of the company, to increase competitiveness, and to obtain significant economic benefits without making large financial expenditures. Each of economical production tools solves a specific part of the problems, and only application of their combination will allow one to solve the problem or minimize it to acceptable values. The research of the governance process project "Lean Production" permitted studying the methods and tools of lean production and developing measures for their improvement.

  10. ["Lean management" in hospitals: potentials and limitations].

    Science.gov (United States)

    Glossmann, J P; Schliebusch, O; Diehl, V; Walshe, R

    2000-08-15

    Little attention has yet been payed on establishing modern and competitive organizational structures in German hospitals. In this paper, we attempt to apply elements of lean management to the work of physicians working in an inpatient setting. Traditional ways of communication and their disadvantages are discussed. These include loss of motivation, bureaucratic structures and a lack of interdisciplinary cooperation. Using Maslow's theory of motivation, possible improvements are discussed, such as the reduction of restrictive job characteristics, an increase of physicians' spheres of competence and the use of their innovative potentials. These suggestions are explained using practical examples. The aim of the study is to contribute to quality management in hospitals by increasing personal responsibilities according to lean management.

  11. Burning mouth syndrome

    Directory of Open Access Journals (Sweden)

    Sudha Jimson

    2015-01-01

    Full Text Available Burning mouth syndrome (BMS is a complex disorder that is characterized by warm or burning sensation in the oral mucosa without changes on physical examination. It occurs more commonly in middle-aged and elderly women and often affects the tip of the tongue, lateral borders, lips, hard and soft palate. This condition is probably of multi-factorial origin, often idiopathic, and its etiopathogensis is unknown. BMS can be classified into two clinical forms namely primary and secondary BMS. As a result, a multidisciplinary approach is required for better control of the symptoms. In addition, psychotherapy and behavioral feedback may also help eliminate the BMS symptoms.

  12. Biomass burning in Africa: As assessment of annually burned biomass

    International Nuclear Information System (INIS)

    Delmas, R.A.; Loudjani, P.; Podaire, A.; Menaut, J.C.

    1991-01-01

    It is now established that biomass burning is the dominant phenomenon that controls the atmospheric chemistry in the tropics. Africa is certainly the continent where biomass burning under various aspects and processes is the greatest. Three different types of burnings have to be considered-bush fires in savanna zones which mainly affect herbaceous flora, forest fires due to forestation for shifting agriculture or colonization of new lands, and the use of wood as fuel. The net release of carbon resulting from deforestation is assumed to be responsible for about 20% of the CO 2 increase in the atmosphere because the burning of forests corresponds to a destorage of carbon from the biospheric reservoir. The amount of reactive of greenhouse gases emitted by biomass burning is directly proportional, through individual emission factors, to the biomass actually burned. This chapter evaluates the biomass annually burned on the African continent as a result of the three main burning processes previously mentioned

  13. Simulation-enhanced lean design process

    Directory of Open Access Journals (Sweden)

    Jon H. Marvel

    2009-07-01

    Full Text Available 72 Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A traditional lean transformation process does not validate the future state before implementation, relying instead on a series of iterations to modify the system until performance is satisfactory. An enhanced lean process that includes future state validation before implementation is presented.  Simulation modeling and experimentation is proposed as the primary validation tool.  Simulation modeling and experimentation extends value stream mapping to include time, the behavior of individual entities, structural variability, random variability, and component interaction effects. Experiments to analyze the model and draw conclusions about whether the lean transformation effectively addresses the current state gap can be conducted.  Industrial applications of the enhanced lean process show it effectiveness.

  14. Where lean construction and value management meet

    OpenAIRE

    Musa, MM; Pasquire, C; Hurst, A

    2016-01-01

    The lean construction (LC) community’s key vision and goal is to provide value, yet they are increasingly challenged with understanding and dealing with the concept of value, with reports that value is one of the weakest points. Regardless of the previous studies and contributions already made on the concept of value in LC, the absence of a consistent understanding of value has resulted in misperceptions and indistinct boundaries with other construction value-related disciplines. Without a co...

  15. Lean Production Practices to Enhance Organisational Performance

    Directory of Open Access Journals (Sweden)

    Shah Satya

    2017-01-01

    Full Text Available Service sector organisations are constantly overcoming the challenges facing the over-production and waste reduction within their environments. Industries are also becoming very competitive thus forcing them to seek suitable production organisation strategies with the aim towards enhancing their competitiveness and efficiency. The aim of this research study is to investigate the impact of lean production practices on the performance of service based businesses through the case study of a local baked goods supplier. The research framework adopted consists of questionnaire survey method implemented with different end users, thus covering the overall production – retail – customer cycle. The research results and analysis justify the objective of the research that lean production practices enhance the performance of the supplier company and the common tool identified were JIT (Just in Time, Value Steam Mapping (VSP and the 5S methods. The results also suggest that JIT method has a higher impact towards improvement on performance relating to quality, speed, dependability, flexibility and cost of the supplier. However, the research study also identifies that one of the major challenges faced by the organisation while adopting lean practices was the lack of commitment from top management, continuous training and employee engagement measures.

  16. Managing Waste Throughout Lean-Green Perspective

    Directory of Open Access Journals (Sweden)

    Lamyaa Mohammed Dawood

    2017-11-01

    Full Text Available Managing waste has been known as a crucial need as it may reduce resource consumption, rigid regulations regarded to the environment and occupational health and safety. Lean and green management are two approaches of management that validate waste. Since performance measures are crucial to improve waste management as its  goals of  to promote the performance of organizations .In this research four primary KPIs have been employed that are significant to lean-green management; operational, environmental, economic and social performance factors, subdivided further into sixteen as (Value stream mapping, life cycle assessment,---etc. Also in this research   determination and ranking of these performance measures and their influence on waste minimization is conducted. Interpretive Structural Modeling (ISM methodology is applied to the classification of Key Performance Indicators (KPIs according to the priority of their importance and the correlation between them and their impact to waste minimization. Cronbach’s Alpha coefficient is employed  to assess the reliability of performance measures to minimize waste, and increase customer  satisfaction.  Results showed that Al-Kufa Cement plant has bad overall performance toward lean green waste management perspective. The highest individual score is for operational performance (6.6 rated as medium. But  the lowest individual score is for economic performance [very bad (2.0].   

  17. In vivo and in vitro studies of hepatic lipid metabolism in lean and reobese fetal pigs

    International Nuclear Information System (INIS)

    Hausman, G.J.; Trusty, C.D.; Martin, R.J.

    1986-01-01

    Fetuses were removed from pregnant (110 days of gestation) sows and 80 to 120 mg liver slices were prepared for two hour incubations with 14 C-palmitate (1 μCi/ml) or 3 H 2 O (1 mCi/ml). In vivo studies were conducted by injecting a single bolus of 0.5 or 10 ml of Liposyn (a 10% safflower oil emulsion) into fetuses (umbilical vein). One hour post injection (Liposyn) fetuses were removed from the uterus. Subsequently liver lipids were extracted and gas chromatographic analysis for 16:0, 18:0, 18:1, 18:2 and 20:4 were performed. Incorporation of C 14 -palmitate into total lipids was higher in lean livers whereas incorporation into CO 2 was independent of fetal strain. Incorporation of 3 H 2 O into triglyceride fatty acids was similar in lean and obese livers. Fatty acid composition of livers indicated strain differences (obese versus lean for 16:0 = 52 vs 27.8%; 18:0 = 20 vs 16.8%; 18:1 = 16.3 vs 32.6%; 20:4 = 8.8 vs 17.6%). There was a similar Liposyn dose dependent increase in the amount of 18:2 in chromatographs of lean (n = 7) and obese (n = 7) livers. Administration of Liposyn caused a significant increase in the amount of 18:1 and 20:4 in lean livers (least squares means +/- SEM, 0 vs 0.5 ml for 20:4 = .31 +/- .03 vs .48 +/- .04) but no increase in preobese livers. These studies illustrate significant alterations in hepatic lipid metabolism in the preobese state

  18. [Surgical treatment of burns : Special aspects of pediatric burns].

    Science.gov (United States)

    Bührer, G; Beier, J P; Horch, R E; Arkudas, A

    2017-05-01

    Treatment of pediatric burn patients is very important because of the sheer frequency of burn wounds and the possible long-term ramifications. Extensive burns need special care and are treated in specialized burn centers. The goal of this work is to present current standards in burn therapy and important innovations in the treatment of burns in children so that the common and small area burn wounds and scalds in pediatric patients in day-to-day dermatological practice can be adequately treated. Analysis of current literature, discussion of reviews, incorporation of current guidelines. Burns in pediatric patients are common. Improvement of survival can be achieved by treatment in burn centers. The assessment of burn depth and area is an important factor for proper treatment. We give an overview for outpatient treatment of partial thickness burns. New methods may result in better long-term outcome. Adequate treatment of burn injuries considering current literature and guidelines improves patient outcome. Rational implementation of new methods is recommended.

  19. An assessment of burn care professionals' attitudes to major burn.

    LENUS (Irish Health Repository)

    Murphy, A D

    2008-06-01

    The resuscitation of severe burn remains a controversial area within the burn care profession. There is ongoing debate as to what percentage burn is associated with a sufficient quality of life to support initial resuscitation efforts. We conducted a survey of delegates at the 39th Annual Meeting of the British Burns Association (2005), regarding attitudes towards resuscitation following major burns. Respondents were asked the maximum percentage total body surface area (TBSA) burn beyond which they would not wish to be resuscitated. They were also asked what maximum TBSA they perceived to be commensurate with an acceptable quality of life (QOL). One hundred and forty three of 300 delegates responded to the questionnaire. Thirty three percent of respondents would not wish to be resuscitated with 50-75% TBSA burns or greater. A further 35% would not wish to have life-sustaining intervention with 75-95% TBSA burns or greater. The remaining 32% indicated that they would not want resuscitation with TBSA burns>95%. Regardless of TBSA affected, 16% would not wish resuscitation if they had full thickness facial burns, a further 10% did not want resuscitation if both their hands and faces were affected. Our survey demonstrates the diversity of personal preference amongst burn care professionals. This would suggest that a unifying philosophy regarding the resuscitation of extensive burns will remain elusive.

  20. [Nitrogen balance assessment in burn patients].

    Science.gov (United States)

    Beça, Andreia; Egipto, Paula; Carvalho, Davide; Correia, Flora; Oliveira, Bruno; Rodrigues, Acácio; Amarante, José; Medina, J Luís

    2010-01-01

    The burn injury probably represents the largest stimulus for muscle protein catabolism. This state is characterized by an accelerated catabolism of the lean or skeletal mass that results in a clinical negative balance of nitrogen and muscle wasting. The determination of an appropriate value for protein intake is essential, since it is positively related to the nitrogen balance (NB) and accordingly several authors argue that a positive NB is the key parameter associated with nutritional improvement of a burn patient. Evaluation of the degree of protein catabolism by assessment of the Nitrogen Balance; Defining of nutritional support (protein needs) to implement in patients with burned surface area (BSA) = 10%. We prospectively evaluated the clinical files and scrutinized the clinical variables of interest. The NB was estimated according to three formulae. Each gram of nitrogen calculated by the NB was then converted into grams of protein, subtracted or added to protein intake (or administered enteric or parenterically) and divided by kg of reference Weight (kg Rweight), in an attempt to estimate the daily protein needs. The cohort consisted of 10 patients, 6 females, with average age of 58(23) years old, a mean of BSA of 21.4(8.4)%, ranging from a minimum of 10.0% and máximum of 35.0%. On average, patients were 58 (23) years old. The average number of days of hospitalization in the burn unit was 64.8(36.5) days. We observed significant differences between the 3 methods used for calculating the NB (p = 0.004), on average the NB was positive. When the formula A was used the average value of NB was higher. Regarding the attempt to estimate the needs of g prot/kg Rweight/day most of the values did not exceed, on average, 2.6 g Prot/kg Rweight/day and no significant differences between patients with a BSA% of 10-20% and with BSA% > 20% were found. Despite being able to estimate the protein catabolism through these formulas and verifying that most values were above zero

  1. Emissions from burning of softwood pellets

    International Nuclear Information System (INIS)

    Olsson, Maria; Kjaellstrand, Jennica

    2004-01-01

    Softwood pellets from three different Swedish manufacturers were burnt in laboratory scale to determine compounds emitted. The emissions were sampled on Tenax cartridges and assessed by gas chromatography and mass spectrometry. No large differences in the emissions from pellets from different manufacturers were observed. The major primary semi-volatile compounds released during flaming burning were 2-methoxyphenols from lignin. The methoxyphenols are of interest due to their antioxidant effect, which may counteract health hazards of aromatic hydrocarbons. Glowing combustion released the carcinogenic benzene as the predominant aromatic compound. However, the benzene emissions were lower than from flaming burning. To relate the results from the laboratory burnings to emissions from pellet burners and pellet stoves, chimney emissions were determined for different burning equipments. The pellet burner emitted benzene as the major aromatic compound, whereas the stove and boiler emitted phenolic antioxidants together with benzene. As the demand for pellets increases, different biomass wastes will be considered as raw materials. Ecological aspects and pollution hazards indicate that wood pellets should be used primarily for residential heating, whereas controlled large-scale combustion should be preferred for pellets made of most other types of biomass waste. (Author)

  2. Minor burn - first aid - slideshow

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/presentations/100213.htm Minor burn - first aid - series—Procedure, part 1 To use ... out of 2 Overview To treat a minor burn, run cool water over the area of the ...

  3. [Burns in adolescents].

    Science.gov (United States)

    Ortiz Rodríguez, R; Domínguez Amillo, E; Soto Beauregard, C; Díaz González, M; López Gutiérrez, J C; Ros Mar, Z; Tovar Larrucea, J A

    2012-04-01

    The aim of this study was to know the epidemiology of burns in teenagers. Burn patients over 11 years old admitted in our Institution in the last 10 years were included. Etiology, burn size, hospital stay, quirurgical interventions and long term sequelae were registered. One thousand and eight patients were admitted, 89 were over 11 years (8.8%), 70.7% were boys and 29.3% girls. Fire was the principal agent in 58 cases (65.1%), due to fireworks in 13 (22.4%), alcohol in 7 (12%), explosion of flammable containers (spray) in 4 (6.8%) and gasoline in 3 (5.2%). Fireworks injuries and spray explosions affected face and hand in 88% cases. The median hospital stay was 8 days after admission (1 to 90). 83.1% required surgical treatment with mean of 1.8 +/- 1.4 interventions and 21.3% had long-term sequelaes that required at least one surgical intervention. Fire is the main cause of burns in adolescents. Fireworks injuries represented a quarter of that lesions, and highlights paint spray explosions as new causative agents. Considering the high morbidity in this age group, with permanent functional and aesthetic sequelae, prevention campaigns are needed to reduce such accidents.

  4. Electrical Burns: First Aid

    Science.gov (United States)

    ... local emergency number if the source of the burn is a high-voltage wire or lightning. Don't get near high-voltage ... 20 feet (about 6 meters) away — farther if wires are jumping and sparking. Don't move a person with ... breathing Heart rhythm problems (arrhythmias) Cardiac ...

  5. Burns - Multiple Languages

    Science.gov (United States)

    ... Translations Russian (Русский) Expand Section Burn Care - Русский (Russian) Bilingual ... Health Information Translations Characters not displaying correctly on this page? See language display issues . Return to the MedlinePlus Health Information ...

  6. One Burn, One Standard

    Science.gov (United States)

    2014-09-01

    PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Giretzlehner M., Haller H. L., Faucher L. D., Pressman M. A., Salinas J., Jeng J. C., 5d. PROJECT NUMBER 5e...AUVA Linz, Austria Lee D. Faucher, MD University of Wisconsin Madison, Wisconsin Melissa A. Pressman , PhD Arizona Burn Center Phoenix

  7. An Experimental Investigation of Self-Excited Combustion Dynamics in a Single Element Lean Direct Injection (LDI) Combustor

    Science.gov (United States)

    Gejji, Rohan M.

    The management of combustion dynamics in gas turbine combustors has become more challenging as strict NOx/CO emission standards have led to engine operation in a narrow, lean regime. While premixed or partially premixed combustor configurations such as the Lean Premixed Pre-vaporized (LPP), Rich Quench Lean burn (RQL), and Lean Direct Injection (LDI) have shown a potential for reduced NOx emissions, they promote a coupling between acoustics, hydrodynamics and combustion that can lead to combustion instabilities. These couplings can be quite complex, and their detailed understanding is a pre-requisite to any engine development program and for the development of predictive capability for combustion instabilities through high-fidelity models. The overarching goal of this project is to assess the capability of high-fidelity simulation to predict combustion dynamics in low-emissions gas turbine combustors. A prototypical lean-direct-inject combustor was designed in a modular configuration so that a suitable geometry could be found by test. The combustor comprised a variable length air plenum and combustion chamber, air swirler, and fuel nozzle located inside a subsonic venturi. The venturi cross section and the fuel nozzle were consistent with previous studies. Test pressure was 1 MPa and variables included geometry and acoustic resonance, inlet temperatures, equivalence ratio, and type of liquid fuel. High-frequency pressure measurements in a well-instrumented metal chamber yielded frequencies and mode shapes as a function of inlet air temperature, equivalence ratio, fuel nozzle placement, and combustor acoustic resonances. The parametric survey was a significant effort, with over 105 tests on eight geometric configurations. A good dataset was obtained that could be used for both operating-point-dependent quantitative comparisons, and testing the ability of the simulation to predict more global trends. Results showed a very strong dependence of instability amplitude on

  8. Methane gas from cow dung

    Energy Technology Data Exchange (ETDEWEB)

    1974-01-01

    The Khadi and Village Industries Commission offers a gobar gas (methane gas) production scheme. The gas plant, available in sizes of 60 to 3000 cu ft, requires only low maintenance expenditures. The cow dung, which is at present being wasted or burned as domestic fuel, can be used for manufacturing methane for fuel gas. The residue will be a good fertilizer for increasing food production. There are now about 4000 gobar gas plants in India.

  9. Industry 4.0 implies lean manufacturing: Research activities in industry 4.0 function as enablers for lean manufacturing

    Directory of Open Access Journals (Sweden)

    Adam Sanders

    2016-09-01

    Full Text Available Purpose: Lean Manufacturing is widely regarded as a potential methodology to improve productivity and decrease costs in manufacturing organisations. The success of lean manufacturing demands consistent and conscious efforts from the organisation, and has to overcome several hindrances. Industry 4.0 makes a factory smart by applying advanced information and communication systems and future-oriented technologies. This paper analyses the incompletely perceived link between Industry 4.0 and lean manufacturing, and investigates whether Industry 4.0 is capable of implementing lean. Executing Industry 4.0 is a cost-intensive operation, and is met with reluctance from several manufacturers. This research also provides an important insight into manufacturers’ dilemma as to whether they can commit into Industry 4.0, considering the investment required and unperceived benefits. Design/methodology/approach: Lean manufacturing is first defined and different dimensions of lean are presented. Then Industry 4.0 is defined followed by representing its current status in Germany. The barriers for implementation of lean are analysed from the perspective of integration of resources. Literatures associated with Industry 4.0 are studied and suitable solution principles are identified to solve the abovementioned barriers of implementing lean. Findings: It is identified that researches and publications in the field of Industry 4.0 held answers to overcome the barriers of implementation of lean manufacturing. These potential solution principles prove the hypothesis that Industry 4.0 is indeed capable of implementing lean. It uncovers the fact that committing into Industry 4.0 makes a factory lean besides being smart. Originality/value: Individual researches have been done in various technologies allied with Industry 4.0, but the potential to execute lean manufacturing was not completely perceived. This paper bridges the gap between these two realms, and identifies

  10. Inducible satellite cell depletion attenuates skeletal muscle regrowth following a scald-burn injury.

    Science.gov (United States)

    Finnerty, Celeste C; McKenna, Colleen F; Cambias, Lauren A; Brightwell, Camille R; Prasai, Anesh; Wang, Ye; El Ayadi, Amina; Herndon, David N; Suman, Oscar E; Fry, Christopher S

    2017-11-01

    Severe burns result in significant skeletal muscle cachexia that impedes recovery. Activity of satellite cells, skeletal muscle stem cells, is altered following a burn injury and likely hinders regrowth of muscle. Severe burn injury induces satellite cell proliferation and fusion into myofibres with greater activity in muscles proximal to the injury site. Conditional depletion of satellite cells attenuates recovery of myofibre area and volume following a scald burn injury in mice. Skeletal muscle regrowth following a burn injury requires satellite cell activity, underscoring the therapeutic potential of satellite cells in the prevention of prolonged frailty in burn survivors. Severe burns result in profound skeletal muscle atrophy; persistent muscle atrophy and weakness are major complications that hamper recovery from burn injury. Many factors contribute to the erosion of muscle mass following burn trauma, and we have previously shown concurrent activation and apoptosis of muscle satellite cells following a burn injury in paediatric patients. To determine the necessity of satellite cells during muscle recovery following a burn injury, we utilized a genetically modified mouse model (Pax7 CreER -DTA) that allows for the conditional depletion of satellite cells in skeletal muscle. Additionally, mice were provided 5-ethynyl-2'-deoxyuridine to determine satellite cell proliferation, activation and fusion. Juvenile satellite cell-wild-type (SC-WT) and satellite cell-depleted (SC-Dep) mice (8 weeks of age) were randomized to sham or burn injury consisting of a dorsal scald burn injury covering 30% of total body surface area. Both hindlimb and dorsal muscles were studied at 7, 14 and 21 days post-burn. SC-Dep mice had >93% depletion of satellite cells compared to SC-WT (P satellite cell proliferation and fusion. Depletion of satellite cells impaired post-burn recovery of both muscle fibre cross-sectional area and volume (P satellite cells in the aetiology of lean

  11. Lean-Prinzipien für verbesserte Kosteneffizienz: Instandhaltungseffizienz durch Lean Maintenance

    OpenAIRE

    Bandow, G.; Schmidt, A.

    2008-01-01

    Die Bedeutung der Instandhaltung nimmt weiter zu. In einem Lean Umfeld mit einer immer verschwendungsärmeren Produktion stehen nicht nur die Kosteneffizienz und Verfügbarkeit der Produktionsmittel im Fokus. Unplanmäßige Stillstände kosten Geld und gefährden häufig auch Personal und Produkt. Lean Maintenance vermeidet Verschwendung und optimiert so die Effektivität und Effizienz der Instandhaltung. Das zielgerichtete Zusammenspiel von Menschen, Prozessen und Technik garantiert dabei den Erfolg...

  12. Lean Thinking and Transferring Lean Management - The Best Defence against an Economic Recession?

    Directory of Open Access Journals (Sweden)

    Daniel D. GEORGESCU

    2011-06-01

    Full Text Available Productivity growth is a fundamental means for society to improve its living standards. Productivity growth comes from technological change (new ways of producing goods and services and better organisation of production (better ways of using available resources given available technology. Both processes operate simultaneously and, in practice, it is difficult to distinguish between the effects of each process. The processes are dynamic and affect individual activities differently over time. These years, manufacturing functions have been transferred rapidly and globally from mature countries to emerging countries. This paper is about the lean philosophy and the critical elements for successful transfer of lean management among sites and countries.

  13. Burn Wise Educational Materials for Businesses

    Science.gov (United States)

    Burn Wise outreach material. Burn Wise is a partnership program of that emphasizes the importance of burning the right wood, the right way, in the right wood-burning appliance to protect your home, health, and the air we breathe.

  14. Repeated Prescribed Burning in Aspen

    Science.gov (United States)

    Donald A. Perala

    1974-01-01

    Infrequent burning weather, low flammability of the aspen-hardwood association, and prolific sprouting and seeding of shrubs and hardwoods made repeated dormant season burning a poor tool to convert good site aspen to conifers. Repeat fall burns for wildlife habitat maintenance is workable if species composition changes are not important.

  15. Air-Freshener Burns: A New Paradigm in Burns Etiology?

    OpenAIRE

    Sarwar, Umran; Nicolaou, M.; Khan, M. S.; Tiernan, E.

    2011-01-01

    Objectives: We report a rare case of burns following the use of automated air-fresheners. Methods: We present a case report with a brief overview of the literature relating to burns associated with air-fresheners. The mechanism and treatment of these types of injuries are also described. Results: A 44 year-old female was admitted under the care of the burns team following burns secondary to an exploding air-freshener canister. The patient sustained burns to the face, thorax and arms re...

  16. Quality improvement in basic histotechnology: the lean approach.

    Science.gov (United States)

    Clark, David

    2016-01-01

    Lean is a comprehensive system of management based on the Toyota production system (TPS), encompassing all the activities of an organization. It focuses management activity on creating value for the end-user by continuously improving operational effectiveness and removing waste. Lean management creates a culture of continuous quality improvement with a strong emphasis on developing the problem-solving capability of staff using the scientific method (Deming's Plan, Do, Check, Act cycle). Lean management systems have been adopted by a number of histopathology departments throughout the world to simultaneously improve quality (reducing errors and shortening turnround times) and lower costs (by increasing efficiency). This article describes the key concepts that make up a lean management system, and how these concepts have been adapted from manufacturing industry and applied to histopathology using a case study of lean implementation and evidence from the literature. It discusses the benefits, limitations, and pitfalls encountered when implementing lean management systems.

  17. Performance effect of multiple control forms in a Lean organization

    DEFF Research Database (Denmark)

    Kristensen, Thomas Borup; Israelsen, Poul

    2012-01-01

    Over the last decades Lean has developed into a prominent management philosophy reaching beyond shop floor tools. However, substantial support of performance effects from Lean is still scarce and at best with mixed results. Recently, research has turned its focus towards perceiving Lean...... as a control package. In this paper we present statistical support for enhanced performance coming from Lean. Furthermore, our results strongly support the perception of Lean as a set of multiple control forms (output, behavioral, and social controls) that complement each other. Therefore, performance...... is increased if the average level of control forms is increased, and performance is further increased if the control forms are balanced at the same level representing a complementary effect between them. Our data are archival data spanning multiple years in a strong Lean organization. The dependent performance...

  18. Lean Management Systems in Radiology: Elements for Success.

    Science.gov (United States)

    Schultz, Stacy R; Ruter, Royce L; Tibor, Laura C

    2016-01-01

    This article is a review of the literature on Lean and Lean Management Systems and how they have been implemented in healthcare organizations and particularly in radiology departments. The review focuses on the elements required for a successful implementation of Lean by applying the principles of a Lean Management System instead of a Lean tools-only approach. This review shares the successes and failures from healthcare organizations' efforts to improve the quality and safety of the services they provide. There are a limited number of healthcare organizations in the literature who have shared their experiences and additional research is necessary to determine whether a Lean Management System is a viable alternative to the current management structure in healthcare.

  19. Is proportion burned severely related to daily area burned?

    International Nuclear Information System (INIS)

    Birch, Donovan S; Morgan, Penelope; Smith, Alistair M S; Kolden, Crystal A; Hudak, Andrew T

    2014-01-01

    The ecological effects of forest fires burning with high severity are long-lived and have the greatest impact on vegetation successional trajectories, as compared to low-to-moderate severity fires. The primary drivers of high severity fire are unclear, but it has been hypothesized that wind-driven, large fire-growth days play a significant role, particularly on large fires in forested ecosystems. Here, we examined the relative proportion of classified burn severity for individual daily areas burned that occurred during 42 large forest fires in central Idaho and western Montana from 2005 to 2007 and 2011. Using infrared perimeter data for wildfires with five or more consecutive days of mapped perimeters, we delineated 2697 individual daily areas burned from which we calculated the proportions of each of three burn severity classes (high, moderate, and low) using the differenced normalized burn ratio as mapped for large fires by the Monitoring Trends in Burn Severity project. We found that the proportion of high burn severity was weakly correlated (Kendall τ = 0.299) with size of daily area burned (DAB). Burn severity was highly variable, even for the largest (95th percentile) in DAB, suggesting that other variables than fire extent influence the ecological effects of fires. We suggest that these results do not support the prioritization of large runs during fire rehabilitation efforts, since the underlying assumption in this prioritization is a positive relationship between severity and area burned in a day. (letters)

  20. Analysis The Leanness of The Supply Chain By Fuzzy QFD

    OpenAIRE

    Mukesh Singh Baghel; Pavan Agrawal

    2014-01-01

    The new systems of doing business in manufacturing have evolved in recent decades Lean production. Lean production can be traced to the 1960s in Japan, when Toyota Motors started innovating changes in mass production to deal with its domestic automotive market. The term “Lean production” was coined around 1989 with the popularity of the book, the machine that can change the world written by researchers at the Massachusetts Institute of Technology (MIT). The term itself was coined ...