Intelligent Exit-Selection Behaviors during a Room Evacuation

NASA Astrophysics Data System (ADS)

Zarita, Zainuddin; Lim Eng, Aik

2012-01-01

A modified version of the existing cellular automata (CA) model is proposed to simulate an evacuation procedure in a classroom with and without obstacles. Based on the numerous literature on the implementation of CA in modeling evacuation motions, it is notable that most of the published studies do not take into account the pedestrian's ability to select the exit route in their models. To resolve these issues, we develop a CA model incorporating a probabilistic neural network for determining the decision-making ability of the pedestrians, and simulate an exit-selection phenomenon in the simulation. Intelligent exit-selection behavior is observed in our model. From the simulation results, it is observed that occupants tend to select the exit closest to them when the density is low, but if the density is high they will go to an alternative exit so as to avoid a long wait. This reflects the fact that occupants may not fully utilize multiple exits during evacuation. The improvement in our proposed model is valuable for further study and for upgrading the safety aspects of building designs.

Positioning Model-Supported, Participatory, Water Management Decision Making under Uncertainty within the Western Philosphical Discourse on Knowledge and Governance

NASA Astrophysics Data System (ADS)

Purkey, D. R.; Escobar, M.; Mehta, V. K.; Forni, L.

2016-12-01

Two important trends currently shape the manner in which water resources planning and decision making occurs. The first relates to the increasing reliance on participatory stakeholder processes as a forum for evaluating water management options and selecting the appropriate course of action. The second relates to the growing recognition that earlier deterministic approaches to this evaluation of options may no longer be appropriate, nor required. The convergence of these two trends poses questions as to the proper role of data, information, analysis and expertise in the inherently social and political process of negotiating water resources management agreements and implementing water resources management interventions. The question of how to discover the best or optimal option in the face of deep uncertainty related to climate change, demography, economic development, and regulatory reform is compelling. More fundamentally the question of whether the "perfect" option even exits to be discovered is perhaps more critical. While this existential question may be new to the water resource management community, it is not new to western political theory. This paper explores early classical philosophical writing related to issues of knowledge and governance as captured in the work of Plato and Aristotle; and then attempts to place a new approach to analysis-supported, stakeholder-driven water resources planning and decision making within this philosophical discourse. Using examples from river systems in California and the Andes, where the theory of Robust Decision Making has been used as an organizing construct for stakeholder processes, it is argued that the expectation that analysis will lead to the discovery of the perfect option is not warranted when stakeholders are engaged in the process of discovering a consensus option. This argument will touch upon issue of the diversity of values, model uncertainty and creditability, and the visualization of model output required to explore the implications of various management options across a range of inherently unknowable future conditions.

A patient mobility framework that travels: European and United States-Mexican comparisons.

PubMed

Laugesen, Miriam J; Vargas-Bustamante, Arturo

2010-10-01

To develop a framework that parsimoniously explains divergent patient mobility in the United States and Europe. Review of studies of patient mobility; data from the 2007 Flash Eurobarometer and the 2001 California Health Interview Survey was analyzed; and we reviewed government policies and documents in the United States and Europe. Four types of patient mobility are defined: primary, complementary, duplicative, and institutionalized. Primary exit occurs when people without comprehensive insurance travel because they cannot afford to pay for health insurance or directly finance care, as in the United States and Mexico. Second, people will exit to buy complementary services not covered, or partially covered by domestic health insurance, in both the United States and Europe. Third, in Europe, patient mobility for duplicative services provides faster or better quality treatment. Finally, governments and insurers can encourage institutionalized exit through expanded delivery options and financing. Institutionalized exit is developing in Europe, but uncoordinated and geographically limited in the United States. This parsimonious framework explains patient mobility by considering domestic health system characteristics relating to cost and quality. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Mean-field theory for pedestrian outflow through an exit.

PubMed

Yanagisawa, Daichi; Nishinari, Katsuhiro

2007-12-01

The average pedestrian flow through an exit is one of the most important indices in evaluating pedestrian dynamics. In order to study the flow in detail, the floor field model, which is a crowd model using cellular automata, is extended by taking into account realistic behavior of pedestrians around the exit. The model is studied by both numerical simulations and cluster analysis to obtain a theoretical expression for the average pedestrian flow through the exit. It is found quantitatively that the effects of exit door width, the wall, and the pedestrian mood of competition or cooperation significantly influence the average flow. The results show that there is a suitable width and position of the exit according to the pedestrians' mood.

Prediction of efficacy for conversion from adjunctive therapy to monotherapy with eslicarbazepine acetate 800 mg once daily for partial-onset epilepsy

PubMed Central

Sunkaraneni, Soujanya; Passarell, Julie A; Ludwig, Elizabeth A; Fiedler-Kelly, Jill; Pitner, Janet K; Grinnell, Todd A; Blum, David

2017-01-01

Purpose Eslicarbazepine acetate (ESL) is a once-daily (QD) oral antiepileptic drug (AED) indicated for partial-onset seizures (POS). Clinical studies of gradual conversion to ESL 1,200 and 1,600 mg QD monotherapies were previously conducted in patients with POS who were not well-controlled by 1 or 2 AEDs. This report describes modeling and simulation of plasma eslicarbazepine (primary active metabolite of ESL) concentrations and time to monotherapy study exit to predict efficacy for conversion to ESL monotherapy at a lower dose of 800 mg, as an option for patients requiring or not tolerating higher doses since this regimen is effective in adjunctive therapy for POS. Patients and methods A previously developed population pharmacokinetic model for ESL monotherapy was used to predict minimum plasma eslicarbazepine concentration (Cmin) in 1,500 virtual patients taking 1 (n=1,000) or 2 (n=500) AEDs at baseline, treated with ESL 400 mg QD for 1 week, followed by 800 mg QD for 17 weeks (similar to ESL monotherapy trials where the other AEDs were withdrawn during the first 6 weeks following titration to the randomized ESL dose). Model-predicted Cmin as a time-varying covariate and number of baseline AEDs were used to determine the weekly probability of each patient meeting exit criteria (65.3% threshold) indicative of worsening seizure control in 500 simulated ESL monotherapy trials. A previously developed extended Cox proportional hazards exposure–response model was used to relate time-varying eslicarbazepine exposure to the time to study exit. Results For virtual patients receiving ESL monotherapy (800 mg QD), the 95% upper prediction limit for exit rate at 112 days of 34.9% in patients taking 1 AED at baseline was well below the 65.3% threshold from historical control trials, while the estimate for patients taking 2 AEDs (70.6%) was slightly above the historical control threshold. Conclusion This model-based assessment supports conversion to ESL 800 mg QD monotherapy for POS in adults taking 1 AED. For patients taking 2 concomitant AEDs, however, prescribers should consider maintenance doses of 1,200 or 1,600 mg ESL QD to reduce the likelihood of seizure worsening if conversion to ESL monotherapy is contemplated. PMID:28721105

Prediction of efficacy for conversion from adjunctive therapy to monotherapy with eslicarbazepine acetate 800 mg once daily for partial-onset epilepsy.

PubMed

Sunkaraneni, Soujanya; Passarell, Julie A; Ludwig, Elizabeth A; Fiedler-Kelly, Jill; Pitner, Janet K; Grinnell, Todd A; Blum, David

2017-01-01

Eslicarbazepine acetate (ESL) is a once-daily (QD) oral antiepileptic drug (AED) indicated for partial-onset seizures (POS). Clinical studies of gradual conversion to ESL 1,200 and 1,600 mg QD monotherapies were previously conducted in patients with POS who were not well-controlled by 1 or 2 AEDs. This report describes modeling and simulation of plasma eslicarbazepine (primary active metabolite of ESL) concentrations and time to monotherapy study exit to predict efficacy for conversion to ESL monotherapy at a lower dose of 800 mg, as an option for patients requiring or not tolerating higher doses since this regimen is effective in adjunctive therapy for POS. A previously developed population pharmacokinetic model for ESL monotherapy was used to predict minimum plasma eslicarbazepine concentration ( C min ) in 1,500 virtual patients taking 1 (n=1,000) or 2 (n=500) AEDs at baseline, treated with ESL 400 mg QD for 1 week, followed by 800 mg QD for 17 weeks (similar to ESL monotherapy trials where the other AEDs were withdrawn during the first 6 weeks following titration to the randomized ESL dose). Model-predicted C min as a time-varying covariate and number of baseline AEDs were used to determine the weekly probability of each patient meeting exit criteria (65.3% threshold) indicative of worsening seizure control in 500 simulated ESL monotherapy trials. A previously developed extended Cox proportional hazards exposure-response model was used to relate time-varying eslicarbazepine exposure to the time to study exit. For virtual patients receiving ESL monotherapy (800 mg QD), the 95% upper prediction limit for exit rate at 112 days of 34.9% in patients taking 1 AED at baseline was well below the 65.3% threshold from historical control trials, while the estimate for patients taking 2 AEDs (70.6%) was slightly above the historical control threshold. This model-based assessment supports conversion to ESL 800 mg QD monotherapy for POS in adults taking 1 AED. For patients taking 2 concomitant AEDs, however, prescribers should consider maintenance doses of 1,200 or 1,600 mg ESL QD to reduce the likelihood of seizure worsening if conversion to ESL monotherapy is contemplated.

Spatial signals link exit from mitosis to spindle position.

PubMed

Falk, Jill Elaine; Tsuchiya, Dai; Verdaasdonk, Jolien; Lacefield, Soni; Bloom, Kerry; Amon, Angelika

2016-05-11

In budding yeast, if the spindle becomes mispositioned, cells prevent exit from mitosis by inhibiting the mitotic exit network (MEN). The MEN is a signaling cascade that localizes to spindle pole bodies (SPBs) and activates the phosphatase Cdc14. There are two competing models that explain MEN regulation by spindle position. In the 'zone model', exit from mitosis occurs when a MEN-bearing SPB enters the bud. The 'cMT-bud neck model' posits that cytoplasmic microtubule (cMT)-bud neck interactions prevent MEN activity. Here we find that 1) eliminating cMT- bud neck interactions does not trigger exit from mitosis and 2) loss of these interactions does not precede Cdc14 activation. Furthermore, using binucleate cells, we show that exit from mitosis occurs when one SPB enters the bud despite the presence of a mispositioned spindle. We conclude that exit from mitosis is triggered by a correctly positioned spindle rather than inhibited by improper spindle position.

A nonlinear q-voter model with deadlocks on the Watts-Strogatz graph

NASA Astrophysics Data System (ADS)

Sznajd-Weron, Katarzyna; Michal Suszczynski, Karol

2014-07-01

We study the nonlinear $q$-voter model with deadlocks on a Watts-Strogats graph. Using Monte Carlo simulations, we obtain so called exit probability and exit time. We determine how network properties, such as randomness or density of links influence exit properties of a model.

Adolescents Exiting Homelessness over Two Years: The Risk Amplification and Abatement Model

ERIC Educational Resources Information Center

Milburn, Norweeta G.; Rice, Eric; Rotheram-Borus, Mary Jane; Mallett, Shelley; Rosenthal, Doreen; Batterham, Phillip; May, Susanne J.; Witkin, Andrea; Duan, Naihua

2009-01-01

The Risk Amplification and Abatement Model (RAAM) demonstrates that negative contact with socializing agents amplify risk, while positive contact abates risk for homeless adolescents. To test this model, the likelihood of exiting homelessness and returning to familial housing at 2 years and stably exiting over time are examined with longitudinal…

Spatial signals link exit from mitosis to spindle position

PubMed Central

Falk, Jill Elaine; Tsuchiya, Dai; Verdaasdonk, Jolien; Lacefield, Soni; Bloom, Kerry; Amon, Angelika

2016-01-01

In budding yeast, if the spindle becomes mispositioned, cells prevent exit from mitosis by inhibiting the mitotic exit network (MEN). The MEN is a signaling cascade that localizes to spindle pole bodies (SPBs) and activates the phosphatase Cdc14. There are two competing models that explain MEN regulation by spindle position. In the 'zone model', exit from mitosis occurs when a MEN-bearing SPB enters the bud. The 'cMT-bud neck model' posits that cytoplasmic microtubule (cMT)-bud neck interactions prevent MEN activity. Here we find that 1) eliminating cMT– bud neck interactions does not trigger exit from mitosis and 2) loss of these interactions does not precede Cdc14 activation. Furthermore, using binucleate cells, we show that exit from mitosis occurs when one SPB enters the bud despite the presence of a mispositioned spindle. We conclude that exit from mitosis is triggered by a correctly positioned spindle rather than inhibited by improper spindle position. DOI: http://dx.doi.org/10.7554/eLife.14036.001 PMID:27166637

A Structural Equation Model of Burnout and Job Exit among Child Protective Services Workers.

ERIC Educational Resources Information Center

Drake, Brett; Yadama, Gautam N.

1996-01-01

Uses a structural equation model to examine the three elements of the Maslach Burnout Inventory (MBI)--emotional exhaustion, depersonalization, and personal accomplishment--in relation to job exit among child protective services workers over a 15-month period. The model was supported, showing the relevance of all three MBI elements of job exit.…

Modeling and assessment of civil aircraft evacuation based on finer-grid

NASA Astrophysics Data System (ADS)

Fang, Zhi-Ming; Lv, Wei; Jiang, Li-Xue; Xu, Qing-Feng; Song, Wei-Guo

2016-04-01

Studying civil aircraft emergency evacuation process by using computer model is an effective way. In this study, the evacuation of Airbus A380 is simulated using a Finer-Grid Civil Aircraft Evacuation (FGCAE) model. In this model, the effect of seat area and others on escape process and pedestrian's "hesitation" before leaving exits are considered, and an optimized rule of exit choice is defined. Simulations reproduce typical characteristics of aircraft evacuation, such as the movement synchronization between adjacent pedestrians, route choice and so on, and indicate that evacuation efficiency will be determined by pedestrian's "preference" and "hesitation". Based on the model, an assessment procedure of aircraft evacuation safety is presented. The assessment and comparison with the actual evacuation test demonstrate that the available exit setting of "one exit from each exit pair" used by practical demonstration test is not the worst scenario. The half exits of one end of the cabin are all unavailable is the worst one, that should be paid more attention to, and even be adopted in the certification test. The model and method presented in this study could be useful for assessing, validating and improving the evacuation performance of aircraft.

Runway Exit Designs for Capacity Improvement Demonstrations. Phase 1: Algorithm Development

NASA Technical Reports Server (NTRS)

Trani, A. A.; Hobeika, A. G.; Sherali, H.; Kim, B. J.; Sadam, C. K.

1990-01-01

A description and results are presented of a study to locate and design rapid runway exits under realistic airport conditions. The study developed a PC-based computer simulation-optimization program called REDIM (runway exit design interactive model) to help future airport designers and planners to locate optimal exits under various airport conditions. The model addresses three sets of problems typically arising during runway exit design evaluations. These are the evaluations of existing runway configurations, addition of new rapid runway turnoffs, and the design of new runway facilities. The model is highly interactive and allows a quick estimation of the expected value of runway occupancy time. Aircraft populations and airport environmental conditions are among the multiple inputs to the model to execute a viable runway location and geometric design solution. The results presented suggest that possible reductions on runway occupancy time (ROT) can be achieved with the use of optimally tailored rapid runway designs for a given aircraft population. Reductions of up to 9 to 6 seconds are possible with the implementation of 30 m/sec variable geometry exits.

An analysis of the viscous flow through a compact radial turbine by the average passage approach

NASA Technical Reports Server (NTRS)

Heidmann, James D.; Beach, Timothy A.

1990-01-01

A steady, three-dimensional viscous average passage computer code is used to analyze the flow through a compact radial turbine rotor. The code models the flow as spatially periodic from blade passage to blade passage. Results from the code using varying computational models are compared with each other and with experimental data. These results include blade surface velocities and pressures, exit vorticity and entropy contour plots, shroud pressures, and spanwise exit total temperature, total pressure, and swirl distributions. The three computational models used are inviscid, viscous with no blade clearance, and viscous with blade clearance. It is found that modeling viscous effects improves correlation with experimental data, while modeling hub and tip clearances further improves some comparisons. Experimental results such as a local maximum of exit swirl, reduced exit total pressures at the walls, and exit total temperature magnitudes are explained by interpretation of the flow physics and computed secondary flows. Trends in the computed blade loading diagrams are similarly explained.

Trends in Exiting Physics Master's. Focus On

ERIC Educational Resources Information Center

Mulvey, Patrick J.; Nicholson, Starr

2014-01-01

A physics master's degree provides the recipient with a variety of career options. Some master's recipients will continue their education at the graduate level in physics or another field, where others enter the workforce pursuing a wide range of employment opportunities. This "Focus On" provides an in-depth analysis of physics…

Effects of injection nozzle exit width on rotating detonation engine

NASA Astrophysics Data System (ADS)

Sun, Jian; Zhou, Jin; Liu, Shijie; Lin, Zhiyong; Cai, Jianhua

2017-11-01

A series of numerical simulations of RDE modeling real injection nozzles with different exit widths are performed in this paper. The effects of nozzle exit width on chamber inlet state, plenum flowfield and detonation propagation are analyzed. The results are compared with that using an ideal injection model. Although the ideal injection model is a good approximation method to model RDE inlet, the two-dimensional effects of real nozzles are ignored in the ideal injection model so that some complicated phenomena such as the reflected waves caused by the nozzle walls and the reversed flow into the nozzles can not be modeled accurately. Additionally, the ideal injection model overpredicts the block ratio. In all the cases that stabilize at one-wave mode, the block ratio increases as the nozzle exit width gets smaller. The dual-wave mode case also has a relatively high block ratio. A pressure oscillation in the plenum with the same main frequency with the rotating detonation wave is observed. A parameter σ is applied to describe the non-uniformity in the plenum. σ increases as the nozzle exit width gets larger. Under some condition, the heat release on the interface of fresh premixed gas layer and detonation products can be strong enough to induce a new detonation wave. A spontaneous mode-transition process is observed for the smallest exit width case. Due to the detonation products existing in the premixed gas layer before the detonation wave, the detonation wave will propagate through reactants and products alternately, and therefore its strength will vary with time, especially near the chamber inlet. This tendency gets weaker as the injection nozzle exit width increases.

Uncertainty, irreversibility, and investment in second-generation biofuels

NASA Astrophysics Data System (ADS)

McCarty, Tanner Joseph

The present study formalizes and quantifies the importance of uncertainty for investment in a corn-stover based cellulosic biofuel plant. Using a real options model we recover prices of gasoline that would trigger entry into the market and calculate the portion of that entry trigger price required to cover cost and the portion that corresponds to risk premium. We then discuss the effect of managerial flexibility on the entry risk premium and the prices of gasoline that would trigger mothballing, reactivation, and exit. Results show that the risk premium required by plants to enter the second-generation biofuel market is likely to be substantial. The analysis also reveals that a break-even approach (which ignores the portion of entry price composed of risk premium), and the traditional Marshallian approach (which ignores the portion of entry price composed of both the risk premium and the drift rate), would significantly underestimate the gasoline entry trigger price and the magnitude of that underestimation increases as both volatility and mean of gasoline prices increase. Results also uncover a great deal of hysteresis (i.e. a range of gasoline prices for which there is neither entry nor exit in the market) in entry/exit behavior by plants. Hysteresis increases as gasoline prices become more volatile. Hysteresis suggests that, at the industry level, positive (negative) demand shocks will have a significant impact on prices (production) and a limited impact on production (prices). In combination all of these results suggest that policies supporting second generation biofuels may have fallen short of their targets because of their failure to alleviate uncertainty.

Career Planning without a Regular Diploma: A Study of High School Students Who Received "Special" Diplomas

ERIC Educational Resources Information Center

Price-Wright, Demetress LaGale

2013-01-01

There is a growing demand by our society and legislature to educate all students equitably in an inclusive general education setting. Societal trends vary as time progresses, but this does not eliminate the growing debate regarding diploma options, exit requirements and future career planning for high school graduates. What does a future look like…

Development of an Aeroelastic Analysis Including a Viscous Flow Model

NASA Technical Reports Server (NTRS)

Keith, Theo G., Jr.; Bakhle, Milind A.

2001-01-01

Under this grant, Version 4 of the three-dimensional Navier-Stokes aeroelastic code (TURBO-AE) has been developed and verified. The TURBO-AE Version 4 aeroelastic code allows flutter calculations for a fan, compressor, or turbine blade row. This code models a vibrating three-dimensional bladed disk configuration and the associated unsteady flow (including shocks, and viscous effects) to calculate the aeroelastic instability using a work-per-cycle approach. Phase-lagged (time-shift) periodic boundary conditions are used to model the phase lag between adjacent vibrating blades. The direct-store approach is used for this purpose to reduce the computational domain to a single interblade passage. A disk storage option, implemented using direct access files, is available to reduce the large memory requirements of the direct-store approach. Other researchers have implemented 3D inlet/exit boundary conditions based on eigen-analysis. Appendix A: Aeroelastic calculations based on three-dimensional euler analysis. Appendix B: Unsteady aerodynamic modeling of blade vibration using the turbo-V3.1 code.

Pressure transfer function of a JT15D nozzle due to acoustic and convected entropy fluctuations

NASA Astrophysics Data System (ADS)

Miles, J. H.

An acoustic transmission matrix analysis of sound propagation in a variable area duct with and without flow is extended to include convected entropy fluctuations. The boundary conditions used in the analysis are a transfer function relating entropy and pressure at the nozzle inlet and the nozzle exit impedance. The nozzle pressure transfer function calculated is compared with JT15D turbofan engine nozzle data. The one dimensional theory for sound propagation in a variable area nozzle with flow but without convected entropy is good at the low engine speeds where the nozzle exit Mach number is low (M=0.2) and the duct exit impedance model is good. The effect of convected entropy appears to be so negligible that it is obscured by the inaccuracy of the nozzle exit impedance model, the lack of information on the magnitude of the convected entropy and its phase relationship with the pressure, and the scatter in the data. An improved duct exit impedance model is required at the higher engine speeds where the nozzle exit Mach number is high (M=0.56) and at low frequencies (below 120 Hz).

Energy Efficient Engine Exhaust Mixer Model Technology

NASA Technical Reports Server (NTRS)

Kozlowski, H.; Larkin, M.

1981-01-01

An exhaust mixer test program was conducted to define the technology required for the Energy Efficient Engine Program. The model configurations of 1/10 scale were tested in two phases. A parametric study of mixer design options, the impact of residual low pressure turbine swirl, and integration of the mixer with the structural pylon of the nacelle were investigated. The improvement of the mixer itself was also studied. Nozzle performance characteristics were obtained along with exit profiles and oil smear photographs. The sensitivity of nozzle performance to tailpipe length, lobe number, mixer penetration, and mixer modifications like scalloping and cutbacks were established. Residual turbine swirl was found detrimental to exhaust system performance and the low pressure turbine system for Energy Efficient Engine was designed so that no swirl would enter the mixer. The impact of mixer/plug gap was also established, along with importance of scalloping, cutbacks, hoods, and plug angles on high penetration mixers.

Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Punit; Nestmann, Franz

2010-09-15

A detailed experimental investigation of the effects of exit blade geometry on the part-load performance of low-head, axial flow propeller turbines is presented. Even as these turbines find important applications in small-scale energy generation using micro-hydro, the relationship between the layout of blade profile, geometry and turbine performance continues to be poorly characterized. The experimental results presented here help understand the relationship between exit tip angle, discharge through the turbine, shaft power, and efficiency. The modification was implemented on two different propeller runners and it was found that the power and efficiency gains from decreasing the exit tip angle couldmore » be explained by a theoretical model presented here based on classical theory of turbomachines. In particular, the focus is on the behaviour of internal parameters like the runner loss coefficient, relative flow angle at exit, mean axial flow velocity and net tangential flow velocity. The study concluded that the effects of exit tip modification were significant. The introspective discussion on the theoretical model's limitation and test facility suggests wider and continued experimentation pertaining to the internal parameters like inlet vortex profile and exit swirl profile. It also recommends thorough validation of the model and its improvement so that it can be made capable for accurate characterization of blade geometric effects. (author)« less

40 CFR 63.5830 - What are my options for meeting the standards for pultrusion operations subject to the 60 weight...

Code of Federal Regulations, 2011 CFR

2011-07-01

... pultrusion machines that meet the criteria in paragraphs (b)(1) through (10) of this section. (1) The... openings to allow material to enter and exit the enclosure. (2) For open bath pultrusion machines with a... entrance of the die. (3) For open bath pultrusion machines without a radio frequency pre-heat unit, the...

40 CFR 63.5830 - What are my options for meeting the standards for pultrusion operations subject to the 60 weight...

Code of Federal Regulations, 2014 CFR

2014-07-01

... pultrusion machines that meet the criteria in paragraphs (b)(1) through (10) of this section. (1) The... openings to allow material to enter and exit the enclosure. (2) For open bath pultrusion machines with a... entrance of the die. (3) For open bath pultrusion machines without a radio frequency pre-heat unit, the...

40 CFR 63.5830 - What are my options for meeting the standards for pultrusion operations subject to the 60 weight...

Code of Federal Regulations, 2013 CFR

2013-07-01

... pultrusion machines that meet the criteria in paragraphs (b)(1) through (10) of this section. (1) The... openings to allow material to enter and exit the enclosure. (2) For open bath pultrusion machines with a... entrance of the die. (3) For open bath pultrusion machines without a radio frequency pre-heat unit, the...

MINIVER upgrade for the AVID system. Volume 2: LANMIN input guide

NASA Technical Reports Server (NTRS)

Engel, C. D.; Schmitz, C. P.

1983-01-01

In order to effectively incorporate MINIVER into the AVID system, several changes to MINIVER were made. The thermal conduction options in MINIVER were removed and a new Explicit Interactive Thermal Structures (EXITS) code was developed. Many upgrades to the MINIVER code were made and a new Langley version of MINIVER called LANMIN was created. A user input guide for LANMIN is provided.

Students with Reading and Writing Challenges: Using Informal Assessment to Assist in Planning for the Transition to Adult Life

ERIC Educational Resources Information Center

Sitlington, Patricia L.

2008-01-01

The transition to adult life for students with reading and writing challenges is an area that is not often addressed. The purpose of this article is to relate the informal assessment process to the broader context of high stakes assessment, high school exit exams, diploma options, and transition planning; identify the competencies needed for a…

Experimental Investigation of a Morphing Nacelle Ducted Fan

NASA Technical Reports Server (NTRS)

Kondor, Shayne A.; Moore, Mark

2005-01-01

The application of Circulation Control to the nacelle of a shrouded fan is proposed as a means to enhance off-design performance of the shrouded fan. Typically, a fixed geometry shroud is efficient at a single operating condition. Modifying circulation about the fixed geometry is proposed as a means to virtually morph the shroud without moving surfaces. This approach will enhance off-design-point performance with minimal complexity, weight, and cost. Termed the Morphing Nacelle, this concept provides an attractive propulsion option for Vertical Take-off and Landing (VTOL) aircraft, such conceptual Personal Air Vehicle (PAV) configurations proposed by NASA. An experimental proof of concept investigation of the Morphing Nacelle is detailed in this paper. A powered model shrouded fan model was constructed with Circulation Control (CC) devices integrated in the inlet and exit of the nacelle. Both CC devices consisted of an annular jet slot directing a jet sheet tangent to a curved surface, generally described as a Coanda surface. The model shroud was tailored for axial flight, with a diffusing inlet, but was operated off-design condition as a static lifting fan. Thrust stand experiments were conducted to determine if the CC devices could effectively improve off-design performance of the shrouded fan. Additional tests were conducted to explore the effectiveness of the CC devices a means to reduce peak static pressure on the ground below a lifting fan. Experimental results showed that off-design static thrust performance of the model was improved when the CC devices were employed under certain conditions. The exhaust CC device alone, while effective in diffusing the fan exhaust and improving weight flow into shroud inlet, tended to diminish performance of the fan with increased CC jet momentum. The inlet CC device was effective at reattaching a normally stalled inlet flow condition, proving an effective means of enhancing performance. A more dramatic improvement in static thrust was obtained when the inlet and exit CC devices were operated in unison, but only over a limited range of CC jet momentum. Operating the nacelle inlet and exit CC devices together proved very effective in reducing peak ground plane static pressure, while maintaining static thrust. The Morphing Nacelle concept proved effective at enhancing off-design performance of the model; however, additional investigation is necessary to generalize the results.

A Generalized Fluid System Simulation Program to Model Flow Distribution in Fluid Networks

NASA Technical Reports Server (NTRS)

Majumdar, Alok; Bailey, John W.; Schallhorn, Paul; Steadman, Todd

1998-01-01

This paper describes a general purpose computer program for analyzing steady state and transient flow in a complex network. The program is capable of modeling phase changes, compressibility, mixture thermodynamics and external body forces such as gravity and centrifugal. The program's preprocessor allows the user to interactively develop a fluid network simulation consisting of nodes and branches. Mass, energy and specie conservation equations are solved at the nodes; the momentum conservation equations are solved in the branches. The program contains subroutines for computing "real fluid" thermodynamic and thermophysical properties for 33 fluids. The fluids are: helium, methane, neon, nitrogen, carbon monoxide, oxygen, argon, carbon dioxide, fluorine, hydrogen, parahydrogen, water, kerosene (RP-1), isobutane, butane, deuterium, ethane, ethylene, hydrogen sulfide, krypton, propane, xenon, R-11, R-12, R-22, R-32, R-123, R-124, R-125, R-134A, R-152A, nitrogen trifluoride and ammonia. The program also provides the options of using any incompressible fluid with constant density and viscosity or ideal gas. Seventeen different resistance/source options are provided for modeling momentum sources or sinks in the branches. These options include: pipe flow, flow through a restriction, non-circular duct, pipe flow with entrance and/or exit losses, thin sharp orifice, thick orifice, square edge reduction, square edge expansion, rotating annular duct, rotating radial duct, labyrinth seal, parallel plates, common fittings and valves, pump characteristics, pump power, valve with a given loss coefficient, and a Joule-Thompson device. The system of equations describing the fluid network is solved by a hybrid numerical method that is a combination of the Newton-Raphson and successive substitution methods. This paper also illustrates the application and verification of the code by comparison with Hardy Cross method for steady state flow and analytical solution for unsteady flow.

Does the Owl Fly out of the Tree or Does the Owl Exit the Tree Flying? How L2 Learners Overcome Their L1 Lexicalization Biases

ERIC Educational Resources Information Center

Song, Lulu; Pulverman, Rachel; Pepe, Christina; Golinkoff, Roberta Michnick; Hirsh-Pasek, Kathy

2016-01-01

Learning a language is more than learning its vocabulary and grammar. For example, compared with English, Spanish uses many more path verbs such as "ascender" ("to move upward") and "salir" ("to go out"), and expresses manner of motion optionally. English, in contrast, has many manner verbs (e.g., "run,…

Evaluation of System Architectures for the Army Aviation Ground Power Unit

DTIC Science & Technology

2014-12-01

this state of operation induces wear that reduces pump life. Variable capacity control methods using a constant displacement pump are drive speed...options for use with constant displacement pumps, the fluid or magnetic coupling devices are the most attractive. Variable frequency control cannot...compressor prior to the combustor. The cmTent system turbine exhaust temperature controls to 1250°F, much higher than the compressor exit

On the Exit Boundary Condition for One-Dimensional Calculations of Pulsed Detonation Engine Performance

NASA Technical Reports Server (NTRS)

Wilson, Jack; Paxson, Daniel E.

2002-01-01

In one-dimensional calculations of pulsed detonation engine (PDE) performance, the exit boundary condition is frequently taken to be a constant static pressure. In reality, for an isolated detonation tube, after the detonation wave arrives at the exit plane, there will be a region of high pressure, which will gradually return to ambient pressure as an almost spherical shock wave expands away from the exit, and weakens. Initially, the flow is supersonic, unaffected by external pressure, but later becomes subsonic. Previous authors have accounted for this situation either by assuming the subsonic pressure decay to be a relaxation phenomenon, or by running a two-dimensional calculation first, including a domain external to the detonation tube, and using the resulting exit pressure temporal distribution as the boundary condition for one-dimensional calculations. These calculations show that the increased pressure does affect the PDE performance. In the present work, a simple model of the exit process is used to estimate the pressure decay time. The planar shock wave emerging from the tube is assumed to transform into a spherical shock wave. The initial strength of the spherical shock wave is determined from comparison with experimental results. Its subsequent propagation, and resulting pressure at the tube exit, is given by a numerical blast wave calculation. The model agrees reasonably well with other, limited, results. Finally, the model was used as the exit boundary condition for a one-dimensional calculation of PDE performance to obtain the thrust wall pressure for a hydrogen-air detonation in tubes of length to diameter ratio (L/D) of 4, and 10, as well as for the original, constant pressure boundary condition. The modified boundary condition had no performance impact for values of L/D > 10, and moderate impact for L/D = 4.

Ethnic variations in immigrant poverty exit and female employment: the missing link.

PubMed

Kaida, Lisa

2015-04-01

Despite widespread interest in poverty among recent immigrants and female immigrant employment, research on the link between the two is limited. This study evaluates the effect of recently arrived immigrant women's employment on the exit from family poverty and considers the implications for ethnic differences in poverty exit. It uses the bivariate probit model and the Fairlie decomposition technique to analyze data from the Longitudinal Survey of Immigrants to Canada (LSIC), a nationally representative survey of immigrants arriving in Canada, 2000-2001. Results show that the employment of recently arrived immigrant women makes a notable contribution to lifting families out of poverty. Moreover, the wide ethnic variations in the probability of exit from poverty between European and non-European groups are partially explained by the lower employment rates among non-European women. The results suggest that the equal earner/female breadwinner model applies to low-income recent immigrant families in general, but the male breadwinner model explains the low probability of poverty exit among select non-European groups whose female employment rates are notably low.

The development of a change model of "exits" during cognitive analytic therapy for the treatment of depression.

PubMed

Sandhu, Sundeep Kaur; Kellett, Stephen; Hardy, Gillian

2017-11-01

"Exits" in cognitive analytic therapy (CAT) are methods that change unhelpful patterns or roles during the final "revision" phase of the therapy. How exits are conceived and achieved is currently poorly understood. This study focussed on the revision stage to explore and define how change is accomplished in CAT. Qualitative content analysis studied transcripts of sessions 6 and 7 of a protocol delivered 8-session CAT treatment for depression. Eight participants met the study inclusion criteria, and therefore, 16 sessions were analysed. The exit model developed contained 3 distinct (but interacting) phases: (a) developing an observing self via therapist input or client self-reflection, (b) breaking out of old patterns by creating new roles and procedures, and (c) utilisation of a range of methods to support and maintain change. Levels of interrater reliability for the exit categories that formed the model were good. The revision stage of CAT emerged as a complex and dynamic process involving 3 interacting stages. Further research is recommended to understand how exits relate to durability of change and whether change processes differ according to presenting problem. Exit work in cognitive analytic therapy is a dynamic process that requires progression through stages of insight, active change, and consolidation. Development of an "observing self" is an important foundation stone for change, and cognitive analytic therapists need to work within the client's zone of proximal development. A number of aspects appear important in facilitating change, such as attending to the process and feelings generated by change talk. Copyright © 2017 John Wiley & Sons, Ltd.

6th Annual CMMI Technology Conference and User Group

DTIC Science & Technology

2006-11-17

Operationally Oriented; Customer Focused Proven Approach – Level of Detail Beginner Decision Table (DT) is a tabular representation with tailoring options to...written to reflect the experience of the author Software Engineering led the process charge in the ’80s – Used Flowcharts – CASE tools – “data...Postpo ned PCR. Verification Steps • EPG configuration audits • EPG configuration status reports Flowcharts and Entry, Task, Verification and eXit

[Prediction and influence factors of the ramp's noise of the entrance or exit of garages].

PubMed

Di, Guo-Qing; Zhang, Bang-Jun

2005-09-01

Some typical entrances/exits of the underground garages are chosen in urban residential areas. On the basis of the optimization of the positions of the noise sampling points and the groupings of the synchronous sampling points, by means of the acoustical analysis of the noise samples, the relation of the correlative factors, among the ramps' noise of the entrances or exits of the garages, the structure, grade, shape of the ramps, upgrade and downgrade, is studied. The prediction model of the ramp's noise influence of the entrance or exit of the garage is established through amending the noise influence of the entrance or exit of the even concrete road.

Teaching Adults with Severe and Profound Retardation to Exit Their Homes upon Hearing the Fire Alarm.

ERIC Educational Resources Information Center

Bannerman, Diane J.; And Others

1991-01-01

Prompting, modeling, and differential reinforcement were used to teach three nonverbal adults with severe to profound mental retardation to exit their group homes at the sound of the house fire alarm. All three learned to exit independently in less than two minutes in all or the majority of surprise fire drills. (Author/JDD)

DOE Office of Scientific and Technical Information (OSTI.GOV)

B. Gardiner; L.Graton; J.Longo

Classified removable electronic media (CREM) are tracked in several different ways at the Laboratory. To ensure greater security for CREM, we are creating a single, Laboratory-wide system to track CREM. We are researching technology that can be used to electronically tag and detect CREM, designing a database to track the movement of CREM, and planning to test the system at several locations around the Laboratory. We focus on affixing ''smart tags'' to items we want to track and installing gates at pedestrian portals to detect the entry or exit of tagged items. By means of an enterprise database, the systemmore » will track the entry and exit of tagged items into and from CREM storage vaults, vault-type rooms, access corridors, or boundaries of secure areas, as well as the identity of the person carrying an item. We are considering several options for tracking items that can give greater security, but at greater expense.« less

Effect of exit locations on ants escaping a two-exit room stressed with repellent

NASA Astrophysics Data System (ADS)

Wang, Shujie; Cao, Shuchao; Wang, Qiao; Lian, Liping; Song, Weiguo

2016-09-01

In order to investigate the effect of the distance between two exits on ant evacuation efficiency and the behavior of ants escaping from a two-exit room, we conducted ant egress experiments using Camponotus japonicus in multiple situations. We found that the ants demonstrated the phenomenon of "symmetry breaking" in this stress situation. It was also shown that different locations for the exits obviously affected the ants' egress efficiency by measuring the time intervals between individual egress and flow rate in eight repeated experiments, each of which contained five different distance between the two exits. In addition, it is demonstrated that there are differences between the predictions of Social Force Model of pedestrians and the behaviors of ants in stress conditions through comparing some important behavioral features, including position, trajectory, velocity, and density map.

Increasing Walking in the Hartsfield-Jackson Atlanta International Airport: The Walk to Fly Study.

PubMed

Fulton, Janet E; Frederick, Ginny M; Paul, Prabasaj; Omura, John D; Carlson, Susan A; Dorn, Joan M

2017-07-01

To test the effectiveness of a point-of-decision intervention to prompt walking, versus motorized transport, in a large metropolitan airport. We installed point-of-decision prompt signage at 4 locations in the airport transportation mall at Hartsfield-Jackson Atlanta International Airport (Atlanta, GA) at the connecting corridor between airport concourses. Six ceiling-mounted infrared sensors counted travelers entering and exiting the study location. We collected traveler counts from June 2013 to May 2016 when construction was present and absent (preintervention period: June 2013-September 2014; postintervention period: September 2014-May 2016). We used a model that incorporated weekly walking variation to estimate the intervention effect on walking. There was an 11.0% to 16.7% relative increase in walking in the absence of airport construction where 580 to 810 more travelers per day chose to walk. Through May 2016, travelers completed 390 000 additional walking trips. The Walk to Fly study demonstrated a significant and sustained increase in the number of airport travelers choosing to walk. Providing signage about options to walk in busy locations where reasonable walking options are available may improve population levels of physical activity and therefore improve public health.

Implementation of Cognitive-Behavioral Substance Abuse Treatment in Sub-Saharan Africa: Treatment Engagement and Abstinence at Treatment Exit.

PubMed

Gouse, Hetta; Magidson, Jessica F; Burnhams, Warren; Remmert, Jocelyn E; Myers, Bronwyn; Joska, John A; Carrico, Adam W

2016-01-01

This study documented the treatment cascade for engagement in care and abstinence at treatment exit as well as examined correlates of these outcomes for the first certified Matrix Model® substance abuse treatment site in Sub-Saharan Africa. This retrospective chart review conducted at a resource-limited community clinic in Cape Town, South Africa, assessed treatment readiness and substance use severity at treatment entry as correlates of the number of sessions attended and biologically confirmed abstinence at treatment exit among 986 clients who initiated treatment from 2009-2014. Sociodemographic and clinical correlates of treatment outcomes were examined using logistic regression, modeling treatment completion and abstinence at treatment exit separately. Of the 2,233 clients who completed screening, approximately 44% (n = 986) initiated treatment. Among those who initiated treatment, 45% completed at least four group sessions, 30% completed early recovery skills training (i.e., at least eight group sessions), and 13% completed the full 16-week program. Approximately half (54%) of clients who provided a urine sample had negative urine toxicology results for any substance at treatment exit. Higher motivation at treatment entry was independently associated with greater odds of treatment completion and negative urine toxicology results at treatment exit. Findings provide initial support for the successful implementation the Matrix Model in a resource-limited setting. Motivational enhancement interventions could support treatment initiation, promote sustained engagement in treatment, and achieve better treatment outcomes.

Outplacement Services in Support of BRAC and Competitive Sourcing Task Group

DTIC Science & Technology

2003-07-30

Management(SM) is an automated Web-based solution that streamlines workforce adjustment initiatives and exit processing, saving time and money by getting...effected during FY02 – almost 7,000. o Over 160,000 employees have been saved from involuntary separation since program inception in 1993. Buyouts...monetary incentive, up to $25,000, for employee to retire, either optional or early, or resign. Payment of the incentive must save another DoD employee

Analysis of the trip costs of a traffic corridor with two entrances and one exit under car-following model

NASA Astrophysics Data System (ADS)

Tang, Tie-Qiao; Wang, Tao; Chen, Liang; Shang, Hua-Yan

2017-11-01

In this paper, we first define each commuter's first, second and third trip costs, and then apply the full velocity difference model and the VT-Micro model to explore each commuter's three trip costs and the system's corresponding total trip costs in a traffic corridor with two entrances and one exit. The numerical results show that one entrance has prominent effects on the commuter's three trip costs and the system's corresponding total trip cost and that the impacts are directly related to the commuter's departure interval at this entrance. The results can provide some suggestions for reducing the commuters' trip costs in a traffic corridor with two entrances and one exit.

Can favourable psychosocial working conditions in midlife moderate the risk of work exit for chronically ill workers? A 20-year follow-up of the Whitehall II study.

PubMed

Fleischmann, Maria; Carr, Ewan; Stansfeld, Stephen A; Xue, Baowen; Head, Jenny

2018-03-01

To investigate if favourable psychosocial working conditions can reduce the risk of work exit and specifically for workers with chronic disease. Men and women (32%) aged 35-55, working and having no chronic disease at baseline of the Whitehall II study of London-based civil servants were selected (n=9040). We observed participants' exit from work through retirement, health-related exit and unemployment, new diagnosis of chronic disease (ie, coronary heart disease, diabetes, stroke and cancer) and their psychosocial working conditions in midlife. Using cause-specific Cox models, we examined the association of chronic disease and favourable psychosocial working conditions and their interaction, with the three types of work exit. We adjusted for gender, occupational grade, educational level, remaining in civil service, spouse's employment status and mental health. Chronic disease significantly increased the risk of any type of work exit (HR 1.27) and specifically the risk of health-related exit (HR 2.42). High skill discretion in midlife reduced the risk of any type of work exit (HR 0.90), retirement (HR 0.91) and health-related exit (HR 0.68). High work social support in midlife decreased the risk of health-related exit (HR 0.79) and unemployment (HR 0.71). Favourable psychosocial working conditions in midlife did not attenuate the association between chronic disease and work exit significantly. The chronically ill have increased risks of work exit, especially through health-related exit routes. Chronic disease is an obstacle to extended working lives. Favourable working conditions directly relate to reduced risks of work exit. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

DESIGN ANALYSIS OF RADIAL INFLOW TURBINES

NASA Technical Reports Server (NTRS)

Glassman, A. J.

1994-01-01

This program performs a velocity-diagram analysis required for determining geometry and estimating performance for radial-inflow turbines. Input design requirements are power, mass flow rate, inlet temperature and pressure, and rotative rate. The design variables include stator-exit angle, rotor-exit-tip to rotor-inlet radius ratio, rotor-exit-hub to tip radius ratio, and the magnitude and radial distribution of rotor-exit tangential velocity. The program output includes diameters, total and static efficiences, all absolute and relative temperatures, pressures, and velocities, and flow angles at stator inlet, stator exit, rotor inlet, and rotor exit. Losses accounted for in this program by the internal loss model are three-dimensional (profile plus end wall) viscous losses in the stator and the rotor, the disk-friction loss on the back side of the rotor, the loss due to the clearance between the rotor tip and the outer casing, and the exit velocity loss. The flow analysis is one-dimensional at the stator inlet, stator exit, and rotor inlet, each of these calculation stations being at a constant radius. At the rotor exit where there is a variation in flow-field radius, an axisymmetric two-dimensional analysis is made using constant height sectors. Simple radial equilibrium is used to establish the static pressure gradient at the rotor exit. This program is written in FORTRAN V and has been implemented on a UNIVAC 1100 series computer with a memory requirement of approximately 22K of 36 bit words.

Introduction of frictional and turning function for pedestrian outflow with an obstacle.

PubMed

Yanagisawa, Daichi; Kimura, Ayako; Tomoeda, Akiyasu; Nishi, Ryosuke; Suma, Yushi; Ohtsuka, Kazumichi; Nishinari, Katsuhiro

2009-09-01

In this paper, two important factors which affect the pedestrian outflow at a bottleneck significantly are studied in detail to analyze the effect of an obstacle setup in front of an exit. One is a conflict at an exit when pedestrians evacuate from a room. We use floor field model for simulating such behavior, which is a well-studied pedestrian model using cellular automata. The conflicts have been taken into account by the friction parameter. However, the friction parameter so far is a constant and does not depend on the number of the pedestrians conflicting at the same time. Thus, we have improved the friction parameter by the frictional function, which is a function of the number of the pedestrians involved in the conflict. Second, we have presented the cost of turning of pedestrians at the exit. Since pedestrians have inertia, their walking speeds decrease when they turn and the pedestrian outflow decreases. The validity of the extended model, which includes the frictional function and the turning function, is supported by the comparison of a mean-field theory and real experiments. We have observed that the pedestrian flow increases when we put an obstacle in front of an exit in our real experiments. The analytical results clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks pedestrians moving to the exit and decreases the average number of pedestrians involved in the conflict. We have also found that an obstacle works more effectively when we shift it from the center since pedestrians go through the exit with less turning.

Design of the transfer line from booster to storage ring at 3 GeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayar, C., E-mail: cafer.bayar@cern.ch; Ciftci, A. K., E-mail: abbas.kenan.ciftci@cern.ch

The Synchrotron Booster Ring accelerates the e-beam up to 3 GeV and particles are transported from booster to storage ring by transfer line. In this study, two options are considered, the first one is a long booster which shares the same tunnel with storage ring and the second one is a compact booster. As a result, two transfer line are designed based on booster options. The optical design is constrained by the e-beam Twiss parameters entering and leaving the transfer line. Twiss parameters in the extraction point of booster are used for the entrance of transfer line and are matchedmore » in the exit of transfer line to the injection point of the storage ring.« less

Determination by ray-tracing of the regions where mid-latitude whistlers exit from the lower ionosphere

NASA Astrophysics Data System (ADS)

Strangeways, H. J.

1981-03-01

The size and position of the regions in the bottomside ionosphere through which downcoming whistlers emerge are estimated using ray-tracing calculations in both summer day and winter night models of the magnetospheric plasma. Consideration is given to the trapping of upgoing whistler-mode waves through both the base and the side of ducts. It is found that for downcoming rays which were trapped in the duct in the summer day model, the limited range of wave-normal angles which can be transmitted from the lower ionosphere to free space below causes the size of the exit point to be considerably smaller than the region of incidence. The exit point is found to be approximately 100 km in size, which agrees with ground-based observations of fairly narrow trace whistlers. For rays trapped in the duct in the winter night model, it is found that the size of the exit point is more nearly the same as the range of final latitudes of the downcoming rays in the lower ionosphere.

Occupational and educational inequalities in exit from employment at older ages: evidence from seven prospective cohorts.

PubMed

Carr, Ewan; Fleischmann, Maria; Goldberg, Marcel; Kuh, Diana; Murray, Emily T; Stafford, Mai; Stansfeld, Stephen; Vahtera, Jussi; Xue, Baowen; Zaninotto, Paola; Zins, Marie; Head, Jenny

2018-05-01

Past studies have identified socioeconomic inequalities in the timing and route of labour market exit at older ages. However, few studies have compared these trends cross-nationally and existing evidence focuses on specific institutional outcomes (such as disability pension and sickness absence) in Nordic countries. We examined differences by education level and occupational grade in the risks of work exit and health-related work exit. Prospective longitudinal data were drawn from seven studies (n=99 164). Participants were in paid work at least once around age 50. Labour market exit was derived based on reductions in working hours, changes in self-reported employment status or from administrative records. Health-related exit was ascertained by receipt of health-related benefit or pension or from the reported reason for stopping work. Cox regression models were estimated for each study, adjusted for baseline self-rated health and birth cohort. There were 50 003 work exits during follow-up, of which an average of 14% (range 2-32%) were health related. Low level education and low occupational grade were associated with increased risks of health-related exit in most studies. Low level education and occupational grade were also associated with an increased risk of any exit from work, although with less consistency across studies. Workers with low socioeconomic position have an increased risk of health-related exit from employment. Policies that extend working life may disadvantage such workers disproportionally, especially where institutional support for those exiting due to poor health is minimal. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A multi-element cosmological model with a complex space-time topology

NASA Astrophysics Data System (ADS)

Kardashev, N. S.; Lipatova, L. N.; Novikov, I. D.; Shatskiy, A. A.

2015-02-01

Wormhole models with a complex topology having one entrance and two exits into the same space-time of another universe are considered, as well as models with two entrances from the same space-time and one exit to another universe. These models are used to build a model of a multi-sheeted universe (a multi-element model of the "Multiverse") with a complex topology. Spherical symmetry is assumed in all the models. A Reissner-Norström black-hole model having no singularity beyond the horizon is constructed. The strength of the central singularity of the black hole is analyzed.

The influence of the stagnation zone on the fluid dynamics at the nozzle exit of a confined and submerged impinging jet

NASA Astrophysics Data System (ADS)

Jeffers, Nicholas; Stafford, Jason; Conway, Ciaran; Punch, Jeff; Walsh, Edmond

2016-02-01

Low profile impinging jets provide a means to achieve high heat transfer coefficients while occupying a small quantity of space. Consequently, they are found in many engineering applications such as electronics cooling, annealing of metals, food processing, and others. This paper investigates the influence of the stagnation zone fluid dynamics on the nozzle exit flow condition of a low profile, submerged, and confined impinging water jet. The jet was geometrically constrained to a round, 16-mm diameter, square-edged nozzle at a jet exit to target surface spacing ( H/ D) that varied between 0.25 < {{ H}{/}{ D}} < 8.75. The influence of turbulent flow regimes is the main focus of this paper; however, laminar flow data are also presented between 1350 < Re < 17{,}300. A custom measurement facility was designed and commissioned to utilise particle image velocimetry in order to quantitatively measure the fluid dynamics both before and after the jet exits its nozzle. The velocity profiles are normalised with the mean velocity across the nozzle exit, and turbulence statistics are also presented. The primary objective of this paper is to present accurate flow profiles across the nozzle exit of an impinging jet confined to a low H/ D, with a view to guide the boundary conditions chosen for numerical simulations confined to similar constraints. The results revealed in this paper suggest that the fluid dynamics in the stagnation zone strongly influences the nozzle exit velocity profile at confinement heights between 0 < {{ H}{/}{ D}} < 1. This is of particular relevance with regard to the choice of inlet boundary conditions in numerical models, and it was found that it is necessary to model a jet tube length {{ L}{/}{ D}} > 0.5—where D is the inner diameter of the jet—in order to minimise modelling uncertainty.

Entrance and exit region friction factor models for annular seal analysis. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Elrod, David Alan

1988-01-01

The Mach number definition and boundary conditions in Nelson's nominally-centered, annular gas seal analysis are revised. A method is described for determining the wall shear stress characteristics of an annular gas seal experimentally. Two friction factor models are developed for annular seal analysis; one model is based on flat-plate flow theory; the other uses empirical entrance and exit region friction factors. The friction factor predictions of the models are compared to experimental results. Each friction model is used in an annular gas seal analysis. The seal characteristics predicted by the two seal analyses are compared to experimental results and to the predictions of Nelson's analysis. The comparisons are for smooth-rotor seals with smooth and honeycomb stators. The comparisons show that the analysis which uses empirical entrance and exit region shear stress models predicts the static and stability characteristics of annular gas seals better than the other analyses. The analyses predict direct stiffness poorly.

Entry and Exit.

DTIC Science & Technology

1987-03-01

1. Introduction R Analyses of industrial competition have attained a new vigor with the application of game -theoretic methods. The process of... competition is represented in models that reflect genuine struggles for entry, market power, and continuing survival. Dynamics and informational effects are...presents a few of the models developed recently to study competitive processes that affect a firm’s entry into a market , and the decision to exit. The

More than a feeling: discrete emotions mediate the relationship between relative deprivation and reactions to workplace furloughs.

PubMed

Osborne, Danny; Smith, Heather J; Huo, Yuen J

2012-05-01

A key insight from investigations of individual relative deprivation (IRD) is that people can experience objective disadvantages differently. In this study, university faculty (N = 953) who reported greater IRD in response to a mandatory furlough (i.e., involuntary pay reductions) were more likely to (a) voice options designed to improve the university (voice), (b) consider leaving their job (exit), and (c) neglect their work responsibilities (neglect), but were (d) less likely to express loyalty to the university (loyalty). Consistent with the emotions literature, (a) anger mediated the relationship between IRD and voice, (b) fear between IRD and exit, (c) sadness between IRD and neglect, and (d) gratitude between IRD and loyalty. IRD was inversely associated with self-reported physical and mental health via these different emotional pathways. These results show how discrete emotions can explain responses to IRD and, in turn, contribute to organizational viability and the health of its members.

Characterization of Carbon Particulates in the Exit Flow of a Plasma Pyrolysis Assembly (PPA) Reactor

NASA Technical Reports Server (NTRS)

Green, Robert D.; Meyer, Marit E.; Agui, Juan H.; Berger, Gordon M.; Vijayakumar, R.; Abney, Morgan B.; Greenwood, Zachary

2015-01-01

The ISS presently recovers oxygen from crew respiration via a Carbon Dioxide Reduction Assembly (CRA) that utilizes the Sabatier chemical process to reduce captured carbon dioxide to methane (CH4) and water. In order to recover more of the hydrogen from the methane and increase oxygen recovery, NASA Marshall Space Flight Center (MSFC) is investigating a technology, plasma pyrolysis, to convert the methane to acetylene. The Plasma Pyrolysis Assembly (or PPA), achieves 90% or greater conversion efficiency, but a small amount of solid carbon particulates are generated as a side product and must be filtered before the acetylene is removed and the hydrogen-rich gas stream is recycled back to the CRA. In this work, we present the experimental results of an initial characterization of the carbon particulates in the PPA exit gas stream. We also present several potential options to remove these carbon particulates via carbon traps and filters to minimize resupply mass and required downtime for regeneration.

USEPA EXAMPLE EXIT LEVEL ANALYSIS RESULTS

EPA Science Inventory

Developed by NERL/ERD for the Office of Solid Waste, the enclosed product provides an example uncertainty analysis (UA) and initial process-based sensitivity analysis (SA) of hazardous waste "exit" concentrations for 7 chemicals and metals using the 3MRA Version 1.0 Modeling Syst...

Insomnia as a predictor of job exit among middle-aged and older adults: results from the Health and Retirement Study.

PubMed

Dong, Liming; Agnew, Jacqueline; Mojtabai, Ramin; Surkan, Pamela J; Spira, Adam P

2017-08-01

Poor health is a recognised predictor of workforce exit, but little is known about the role of insomnia in workforce exit. We examined the association between insomnia symptoms and subsequent job exit among middle-aged and older adults from the Health and Retirement Study (HRS). The study sample consisted of 5746 respondents aged between 50 and 70 who were working for pay when interviewed in the HRS 2004 and were followed up in the HRS 2006. Multinomial logistic regression was used to determine the association between number of insomnia symptoms (0, 1-2, 3-4) and job exit (no exit, health-related exit or exit due to other reasons). In models adjusting for demographic characteristics, baseline health status and baseline job characteristics, compared with respondents with no insomnia symptoms, those with 3-4 insomnia symptoms had approximately twice the odds of leaving the workforce due to poor health (adjusted relative risk ratio=1.93, 95% CI 1.04 to 3.58, p=0.036). There was no association between insomnia and job exit due to non-health reasons. An elevated number of insomnia symptoms is independently associated with leaving paid employment. Workplace screening for and treatment of insomnia symptoms may prolong labour force participation of middle-aged and older adults. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 1. Biosafety Level 4 Suit Laboratory Suite Entry and Exit Procedures.

PubMed

Janosko, Krisztina; Holbrook, Michael R; Adams, Ricky; Barr, Jason; Bollinger, Laura; Newton, Je T'aime; Ntiforo, Corrie; Coe, Linda; Wada, Jiro; Pusl, Daniela; Jahrling, Peter B; Kuhn, Jens H; Lackemeyer, Matthew G

2016-10-03

Biosafety level 4 (BSL-4) suit laboratories are specifically designed to study high-consequence pathogens for which neither infection prophylaxes nor treatment options exist. The hallmarks of these laboratories are: custom-designed airtight doors, dedicated supply and exhaust airflow systems, a negative-pressure environment, and mandatory use of positive-pressure ("space") suits. The risk for laboratory specialists working with highly pathogenic agents is minimized through rigorous training and adherence to stringent safety protocols and standard operating procedures. Researchers perform the majority of their work in BSL-2 laboratories and switch to BSL-4 suit laboratories when work with a high-consequence pathogen is required. Collaborators and scientists considering BSL-4 projects should be aware of the challenges associated with BSL-4 research both in terms of experimental technical limitations in BSL-4 laboratory space and the increased duration of such experiments. Tasks such as entering and exiting the BSL-4 suit laboratories are considerably more complex and time-consuming compared to BSL-2 and BSL-3 laboratories. The focus of this particular article is to address basic biosafety concerns and describe the entrance and exit procedures for the BSL-4 laboratory at the NIH/NIAID Integrated Research Facility at Fort Detrick. Such procedures include checking external systems that support the BSL-4 laboratory, and inspecting and donning positive-pressure suits, entering the laboratory, moving through air pressure-resistant doors, and connecting to air-supply hoses. We will also discuss moving within and exiting the BSL-4 suit laboratories, including using the chemical shower and removing and storing positive-pressure suits.

Safety Precautions and Operating Procedures in an (A)BSL-4 Laboratory: 1. Biosafety Level 4 Suit Laboratory Suite Entry and Exit Procedures

PubMed Central

Janosko, Krisztina; Holbrook, Michael R.; Adams, Ricky; Barr, Jason; Bollinger, Laura; Newton, Je T'aime; Ntiforo, Corrie; Coe, Linda; Wada, Jiro; Pusl, Daniela; Jahrling, Peter B.; Kuhn, Jens H.; Lackemeyer, Matthew G.

2016-01-01

Biosafety level 4 (BSL-4) suit laboratories are specifically designed to study high-consequence pathogens for which neither infection prophylaxes nor treatment options exist. The hallmarks of these laboratories are: custom-designed airtight doors, dedicated supply and exhaust airflow systems, a negative-pressure environment, and mandatory use of positive-pressure (“space”) suits. The risk for laboratory specialists working with highly pathogenic agents is minimized through rigorous training and adherence to stringent safety protocols and standard operating procedures. Researchers perform the majority of their work in BSL-2 laboratories and switch to BSL-4 suit laboratories when work with a high-consequence pathogen is required. Collaborators and scientists considering BSL-4 projects should be aware of the challenges associated with BSL-4 research both in terms of experimental technical limitations in BSL-4 laboratory space and the increased duration of such experiments. Tasks such as entering and exiting the BSL-4 suit laboratories are considerably more complex and time-consuming compared to BSL-2 and BSL-3 laboratories. The focus of this particular article is to address basic biosafety concerns and describe the entrance and exit procedures for the BSL-4 laboratory at the NIH/NIAID Integrated Research Facility at Fort Detrick. Such procedures include checking external systems that support the BSL-4 laboratory, and inspecting and donning positive-pressure suits, entering the laboratory, moving through air pressure-resistant doors, and connecting to air-supply hoses. We will also discuss moving within and exiting the BSL-4 suit laboratories, including using the chemical shower and removing and storing positive-pressure suits. PMID:27768063

Work, Health, and Family at Older Ages in Japan

PubMed Central

Raymo, James M.; Liang, Jersey; Kobayashi, Erika; Sugihara, Yoko; Fukaya, Taro

2010-01-01

In this paper, we investigate ways in which the relationship between health and labor force exit at older ages is moderated by family characteristics. Using two waves of data from a national sample of older Japanese men collected 1999 and 2002, we estimate logistic regression models for labor force exit beyond age 63 as a function of health change, family characteristics, and their interactions. We confirm that poor health is strongly associated with labor force exit and find evidence that moderating influences of family context depend upon the level of health. However, results are only partially consistent with hypotheses that the relationship between health and the likelihood of labor force exit should be stronger for (a) those with good health and family incentives to exit the labor force and (b) those with poor health and family incentives to remain in the labor force. PMID:23082037

Quantifying groundwater dependency of riparian surface hydrologic features using the exit gradient

EPA Science Inventory

This study examines groundwater exit gradients as a way to quantify groundwater interactions with surface water. We calibrated high resolution groundwater models for the basin fill sediments in the lower Calapooia watershed, Oregon, using data collected between 1928--2000. The e...

Evacuation dynamic and exit optimization of a supermarket based on particle swarm optimization

NASA Astrophysics Data System (ADS)

Li, Lin; Yu, Zhonghai; Chen, Yang

2014-12-01

A modified particle swarm optimization algorithm is proposed in this paper to investigate the dynamic of pedestrian evacuation from a fire in a public building-a supermarket with multiple exits and configurations of counters. Two distinctive evacuation behaviours featured by the shortest-path strategy and the following-up strategy are simulated in the model, accounting for different categories of age and sex of the pedestrians along with the impact of the fire, including gases, heat and smoke. To examine the relationship among the progress of the overall evacuation and the layout and configuration of the site, a series of simulations are conducted in various settings: without a fire and with a fire at different locations. Those experiments reveal a general pattern of two-phase evacuation, i.e., a steep section and a flat section, in addition to the impact of the presence of multiple exits on the evacuation along with the geographic locations of the exits. For the study site, our simulations indicated the deficiency of the configuration and the current layout of this site in the process of evacuation and verified the availability of proposed solutions to resolve the deficiency. More specifically, for improvement of the effectiveness of the evacuation from the site, adding an exit between Exit 6 and Exit 7 and expanding the corridor at the right side of Exit 7 would significantly reduce the evacuation time.

Transgenic C. elegans dauer larvae expressing hookworm phospho null DAF-16/FoxO exit dauer.

PubMed

Gelmedin, Verena; Brodigan, Thomas; Gao, Xin; Krause, Michael; Wang, Zhu; Hawdon, John M

2011-01-01

Parasitic hookworms and the free-living model nematode Caenorhabtidis elegans share a developmental arrested stage, called the dauer stage in C. elegans and the infective third-stage larva (L3) in hookworms. One of the key transcription factors that regulate entrance to and exit from developmental arrest is the forkhead transcription factor DAF-16/FoxO. During the dauer stage, DAF-16 is activated and localized in the nucleus. DAF-16 is negatively regulated by phosphorylation by the upstream kinase AKT, which causes DAF-16 to localize out of the nucleus and the worm to exit from dauer. DAF-16 is conserved in hookworms, and hypothesized to control recovery from L3 arrest during infection. Lacking reverse genetic techniques for use in hookworms, we used C. elegans complementation assays to investigate the function of Ancylostoma caninum DAF-16 during entrance and exit from L3 developmental arrest. We performed dauer switching assays and observed the restoration of the dauer phenotype when Ac-DAF-16 was expressed in temperature-sensitive dauer defective C. elegans daf-2(e1370);daf-16(mu86) mutants. AKT phosphorylation site mutants of Ac-DAF-16 were also able to restore the dauer phenotype, but surprisingly allowed dauer exit when temperatures were lowered. We used fluorescence microscopy to localize DAF-16 during dauer and exit from dauer in C. elegans DAF-16 mutant worms expressing Ac-DAF-16, and found that Ac-DAF-16 exited the nucleus during dauer exit. Surprisingly, Ac-DAF-16 with mutated AKT phosphorylation sites also exited the nucleus during dauer exit. Our results suggest that another mechanism may be involved in the regulation DAF-16 nuclear localization during recovery from developmental arrest.

Impact of reduced near-field entrainment of overpressured volcanic jets on plume development

USGS Publications Warehouse

Saffaraval, Farhad; Solovitz, Stephen A.; Ogden, Darcy E.; Mastin, Larry G.

2012-01-01

Volcanic plumes are often studied using one-dimensional analytical models, which use an empirical entrainment ratio to close the equations. Although this ratio is typically treated as constant, its value near the vent is significantly reduced due to flow development and overpressured conditions. To improve the accuracy of these models, a series of experiments was performed using particle image velocimetry, a high-accuracy, full-field velocity measurement technique. Experiments considered a high-speed jet with Reynolds numbers up to 467,000 and exit pressures up to 2.93 times atmospheric. Exit gas densities were also varied from 0.18 to 1.4 times that of air. The measured velocity was integrated to determine entrainment directly. For jets with exit pressures near atmospheric, entrainment was approximately 30% less than the fully developed level at 20 diameters from the exit. At pressures nearly three times that of the atmosphere, entrainment was 60% less. These results were introduced into Plumeria, a one-dimensional plume model, to examine the impact of reduced entrainment. The maximum column height was only slightly modified, but the critical radius for collapse was significantly reduced, decreasing by nearly a factor of two at moderate eruptive pressures.

Jet Exit Rig Six Component Force Balance

NASA Technical Reports Server (NTRS)

Castner, Raymond; Wolter, John; Woike, Mark; Booth, Dennis

2012-01-01

A new six axis air balance was delivered to the NASA Glenn Research Center. This air balance has an axial force capability of 800 pounds, primary airflow of 10 pounds per second, and a secondary airflow of 3 pounds per second. Its primary use was for the NASA Glenn Jet Exit Rig, a wind tunnel model used to test both low-speed, and high-speed nozzle concepts in a wind tunnel. This report outlines the installation of the balance in the Jet Exit Rig, and the results from an ASME calibration nozzle with an exit area of 8 square-inches. The results demonstrated the stability of the force balance for axial measurements and the repeatability of measurements better than 0.20 percent.

10 CFR 431.202 - Definitions concerning illuminated exit signs.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Section 431.202 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN... watts (W). For exit sign models with rechargeable batteries, input power demand shall be measured with batteries at full charge. [70 FR 60417, Oct. 18, 2005, as amended at 71 FR 71372, Dec. 8, 2006] Test...

10 CFR 431.202 - Definitions concerning illuminated exit signs.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Section 431.202 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY EFFICIENCY PROGRAM FOR CERTAIN... watts (W). For exit sign models with rechargeable batteries, input power demand shall be measured with batteries at full charge. [70 FR 60417, Oct. 18, 2005, as amended at 71 FR 71372, Dec. 8, 2006] Test...

Modeling of Elastic Collisions between High Energy and Slow Neutral Atoms

DTIC Science & Technology

2015-07-01

cylindrical test cell, and the currents on the four different electrodes-Inner Cylinder , Exit Plate, Back Aperture, and Collector Plat~were measured...Inner Cylinder electrode. Nevertheless, the neutral atom current to the Inner Cylinder electrode predicted by the VHS model is comparable to the...Figure 9. Normalized curre nt at the Inner Cylinder e lectrode. the point of collision. T he discrepancy in the Exit Plate neutral atom current is due to

The Exit Gradient As a Measure of Groundwater Dependency of Watershed Ecosystem Services

NASA Astrophysics Data System (ADS)

Faulkner, B. R.; Canfield, T. J.; Justin, G. F.

2014-12-01

Flux of groundwater to surface water is often of great interest for the determination of the groundwater dependency of ecosystem services, such as maintenance of wetlands and of baseflow as a contributor to stream channel storage. It is difficult to measure. Most methods are based on coarse mass balance estimates or seepage meters. One drawback of these methods is they are not entirely spatially explicit. The exit gradient is commonly used in engineering studies of hydraulic structures affected by groundwater flow. It can be simply defined in the groundwater modeling context as the ratio of the difference between the computed head and the land surface elevation, for each computational cell, to the thickness of the cell, as it varies in space. When combined with calibrated groundwater flow models, it also has the potential to be useful in watershed scale evaluations of groundwater dependency in a spatially explicit way. We have taken advantage of calibrated models for the Calapooia watershed, Oregon, to map exit gradients for the watershed. Streams in the Calapooia are hydraulically well connected with groundwater. Not surprisingly, we found large variations in exit gradients between wet and dry season model runs, supporting the notion of stream expansion, as observed in the field, which may have a substantial influence on water quality. We have mapped the exit gradients in the wet and dry seasons, and compared them to regions which have been mapped in wetland surveys. Those classified as Palustrine types fell largest in the area of contribution from groundwater. In many cases, substantially high exit gradients, even on average, did not correspond to mapped wetland areas, yet nutrient retention ecosystem services may still be playing a role in these areas. The results also reinforce the notion of the importance of baseflow to maintenance of stream flow, even in the dry summer season in this Temperate/Mediterranean climate. Exit gradient mapping is a simple, yet potentially very useful and underutilized tool for measuring groundwater dependency in watershed scale ecosystem services studies, and could potentially be used to predict effects due to groundwater stresses resulting from water withdrawals. This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.

Cognitive learning during surgical residency. A model for curriculum evaluation.

PubMed

Rhodes, R S; Wile, M Z; Persons, M L; Shuck, J M

1987-02-01

The program summary of the American Board of Surgery In-Service Training Exam (ABSITE) can be used to quantitate cognitive learning during a surgical residency and to identify areas of curricular weakness in a residency program. Knowledge on each question is categorized as high (known) or low (unknown) depending on the percentage of residents who answered correctly. Knowledge of Level 1 (entry) residents is then compared with Level 5 (exit) residents. Each ABSITE question can thus be categorized on entry versus exit as known-known, unknown-unknown, unknown-known, and known-unknown. Only about half of unknown knowledge on entry appears to become known on exit. Very little knowledge known on entry becomes unknown on exit. Weaknesses in specific subject areas can be readily identified by ranking questions according to the number of exiting residents who answer incorrectly. Use of this technique to quantitate cognitive learning in a residency program may allow objective assessment of changes in curriculum.

An item response theory analysis of the Executive Interview and development of the EXIT8: A Project FRONTIER Study.

PubMed

Jahn, Danielle R; Dressel, Jeffrey A; Gavett, Brandon E; O'Bryant, Sid E

2015-01-01

The Executive Interview (EXIT25) is an effective measure of executive dysfunction, but may be inefficient due to the time it takes to complete 25 interview-based items. The current study aimed to examine psychometric properties of the EXIT25, with a specific focus on determining whether a briefer version of the measure could comprehensively assess executive dysfunction. The current study applied a graded response model (a type of item response theory model for polytomous categorical data) to identify items that were most closely related to the underlying construct of executive functioning and best discriminated between varying levels of executive functioning. Participants were 660 adults ages 40 to 96 years living in West Texas, who were recruited through an ongoing epidemiological study of rural health and aging, called Project FRONTIER. The EXIT25 was the primary measure examined. Participants also completed the Trail Making Test and Controlled Oral Word Association Test, among other measures, to examine the convergent validity of a brief form of the EXIT25. Eight items were identified that provided the majority of the information about the underlying construct of executive functioning; total scores on these items were associated with total scores on other measures of executive functioning and were able to differentiate between cognitively healthy, mildly cognitively impaired, and demented participants. In addition, cutoff scores were recommended based on sensitivity and specificity of scores. A brief, eight-item version of the EXIT25 may be an effective and efficient screening for executive dysfunction among older adults.

Sequenced treatment alternatives to relieve depression (STAR*D): rationale and design.

PubMed

Rush, A John; Fava, Maurizio; Wisniewski, Stephen R; Lavori, Philip W; Trivedi, Madhukar H; Sackeim, Harold A; Thase, Michael E; Nierenberg, Andrew A; Quitkin, Frederic M; Kashner, T Michael; Kupfer, David J; Rosenbaum, Jerrold F; Alpert, Jonathan; Stewart, Jonathan W; McGrath, Patrick J; Biggs, Melanie M; Shores-Wilson, Kathy; Lebowitz, Barry D; Ritz, Louise; Niederehe, George

2004-02-01

STAR*D is a multisite, prospective, randomized, multistep clinical trial of outpatients with nonpsychotic major depressive disorder. The study compares various treatment options for those who do not attain a satisfactory response with citalopram, a selective serotonin reuptake inhibitor antidepressant. The study enrolls 4000 adults (ages 18-75) from both primary and specialty care practices who have not had either a prior inadequate response or clear-cut intolerance to a robust trial of protocol treatments during the current major depressive episode. After receiving citalopram (level 1), participants without sufficient symptomatic benefit are eligible for randomization to level 2 treatments, which entail four switch options (sertraline, bupropion, venlafaxine, cognitive therapy) and three citalopram augment options (bupropion, buspirone, cognitive therapy). Those who receive cognitive therapy (switch or augment options) at level 2 without sufficient improvement are eligible for randomization to one of two level 2A switch options (venlafaxine or bupropion). Level 2 and 2A participants are eligible for random assignment to two switch options (mirtazapine or nortriptyline) and to two augment options (lithium or thyroid hormone) added to the primary antidepressant (citalopram, bupropion, sertraline, or venlafaxine) (level 3). Those without sufficient improvement at level 3 are eligible for level 4 random assignment to one of two switch options (tranylcypromine or the combination of mirtazapine and venlafaxine). The primary outcome is the clinician-rated, 17-item Hamilton Rating Scale for Depression, administered at entry and exit from each treatment level through telephone interviews by assessors masked to treatment assignments. Secondary outcomes include self-reported depressive symptoms, physical and mental function, side-effect burden, client satisfaction, and health care utilization and cost. Participants with an adequate symptomatic response may enter the 12-month naturalistic follow-up phase with brief monthly and more complete quarterly assessments.

Computer Modeling of a Rotating Detonation Engine in a Rocket Configuration

DTIC Science & Technology

2015-03-01

than the ambient pressure P0, the nozzle was fully supersonic . If the calculated pressure P9 after the normal shock was less than the ambient...18 Gas Properties...66 vii Nomenclature Variable Definition 3∗ Entrance to RDE 4 RDE exit 8 Nozzle 9 Nozzle exit A Area a Speed of

A Longitudinal Study of Welfare Exit among American Indian Families

ERIC Educational Resources Information Center

Pandey, Shanta; Guo, Baorong

2007-01-01

Data from a longitudinal survey of families from three reservations (Navajo Nation, San Carlos, and Salt River) in Arizona were used to examine their probability of welfare use. Logistic regression models were used to estimate the effects of individual, family, and structural factors on welfare exit. Results indicate that their probability of…

Entrance loss coefficients and exit coefficients for a physical model of the glottis with convergent angles

PubMed Central

Fulcher, Lewis P.; Scherer, Ronald C.; Anderson, Nicholas V.

2014-01-01

Pressure distributions were obtained for 5°, 10°, and 20° convergent angles with a static physical model (M5) of the glottis. Measurements were made for minimal glottal diameters from d = 0.005–0.32 cm with a range of transglottal pressures of interest for phonation. Entrance loss coefficients were calculated at the glottal entrance for each minimal diameter and transglottal pressure to measure how far the flows in this region deviate from Bernoulli flow. Exit coefficients were also calculated to determine the presence and magnitude of pressure recovery near the glottal exit. The entrance loss coefficients for the three convergent angles vary from values near 2.3–3.4 for d = 0.005 cm to values near 0.6 for d = 0.32 cm. These coefficients extend the tables of entrance loss and exit coefficients obtained for the uniform glottis according to Fulcher, Scherer, and Powell [J. Acoust. Soc. Am. 129, 1548–1553 (2011)]. PMID:25190404

A PP2A-B55 recognition signal controls substrate dephosphorylation kinetics during mitotic exit

PubMed Central

Cundell, Michael J.; Holder, James

2016-01-01

PP2A-B55 is one of the major phosphatases regulating cell division. Despite its importance for temporal control during mitotic exit, how B55 substrates are recognized and differentially dephosphorylated is unclear. Using phosphoproteomics combined with kinetic modeling to extract B55-dependent rate constants, we have systematically identified B55 substrates and assigned their temporal order in mitotic exit. These substrates share a bipartite polybasic recognition determinant (BPR) flanking a Cdk1 phosphorylation site. Experiments and modeling show that dephosphorylation rate is encoded into B55 substrates, including its inhibitor ENSA, by cooperative action of basic residues within the BPR. A complementary acidic surface on B55 decodes this signal, supporting a cooperative electrostatic mechanism for substrate selection. A further level of specificity is encoded into B55 substrates because B55 displays selectivity for phosphothreonine. These simple biochemical properties, combined with feedback control of B55 activity by the phosphoserine-containing substrate/inhibitor ENSA, can help explain the temporal sequence of events during exit from mitosis. PMID:27551054

Effect of second to first normal stress difference ratio at the die exit on neck-in phenomenon in polymeric flat film production

NASA Astrophysics Data System (ADS)

Barborik, Tomas; Zatloukal, Martin

2017-05-01

In this study, viscoelastic modeling of the extrusion film casting process, based on the lD membrane model and modified Leonov constitutive equation, was conducted and the effect of the viscoelastic stress state at the die exit (captured here via second to first normal stress difference ratio) on the unwanted neck-in phenomenon has been analyzed for wide range of Deborah numbers and materials having different level of uniaxial and planar extensional strain hardening. Relevant experimental data for LDPE and theoretical predictions based on multimode eXtended Pom-Pom model acquired from the open literature were used for the validation purposes. It was found that firstly, the predicting capabilities of both constitutive equations for given material and processing conditions are comparable even if the single mode modified Leonov model was used and secondly, the agreement between theoretical and experimental data on neck-in is fairly good. Results of the theoretical study revealed that the viscoelastic stress state at the die exit (i.e. -N2/N1 ratio) increases the level of neck-in if uniaxial extensional strain hardening, planar to uniaxial extensional viscosity ratio and Deborah number increases. It has also been revealed that there exists threshold value for Deborah number and extensional strain hardening below which the neck-in becomes independent on the die exit stress state.

Microscopic information processing and communication in crowd dynamics

NASA Astrophysics Data System (ADS)

Henein, Colin Marc; White, Tony

2010-11-01

Due, perhaps, to the historical division of crowd dynamics research into psychological and engineering approaches, microscopic crowd models have tended toward modelling simple interchangeable particles with an emphasis on the simulation of physical factors. Despite the fact that people have complex (non-panic) behaviours in crowd disasters, important human factors in crowd dynamics such as information discovery and processing, changing goals and communication have not yet been well integrated at the microscopic level. We use our Microscopic Human Factors methodology to fuse a microscopic simulation of these human factors with a popular microscopic crowd model. By tightly integrating human factors with the existing model we can study the effects on the physical domain (movement, force and crowd safety) when human behaviour (information processing and communication) is introduced. In a large-room egress scenario with ample exits, information discovery and processing yields a crowd of non-interchangeable individuals who, despite close proximity, have different goals due to their different beliefs. This crowd heterogeneity leads to complex inter-particle interactions such as jamming transitions in open space; at high crowd energies, we found a freezing by heating effect (reminiscent of the disaster at Central Lenin Stadium in 1982) in which a barrier formation of naïve individuals trying to reach blocked exits prevented knowledgeable ones from exiting. Communication, when introduced, reduced this barrier formation, increasing both exit rates and crowd safety.

Mixing of Supersonic Streams

NASA Technical Reports Server (NTRS)

Hawk, C. W.; Landrum, D. B.; Muller, S.; Turner, M.; Parkinson, D.

1998-01-01

The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ingested air for successful operation in the ramjet and scramjet modes. It is desirable to delay this mixing process in the air-augmented mode of operation present during low speed flight. A model of the Strutjet device has been built and is undergoing test to investigate the mixing of the streams as a function of distance from the Strutjet exit plane during simulated low speed flight conditions. Cold flow testing of a 1/6 scale Strutjet model is underway and nearing completion. Planar Laser Induced Fluorescence (PLIF) diagnostic methods are being employed to observe the mixing of the turbine exhaust gas with the gases from both the primary rockets and the ingested air simulating low speed, air augmented operation of the RBCC. The ratio of the pressure in the turbine exhaust duct to that in the rocket nozzle wall at the point of their intersection is the independent variable in these experiments. Tests were accomplished at values of 1.0, 1.5 and 2.0 for this parameter. Qualitative results illustrate the development of the mixing zone from the exit plane of the model to a distance of about 10 rocket nozzle exit diameters downstream. These data show the mixing to be confined in the vertical plane for all cases, The lateral expansion is more pronounced at a pressure ratio of 1.0 and suggests that mixing with the ingested flow would be likely beginning at a distance of 7 nozzle exit diameters downstream of the nozzle exit plane.

Radiological Tenckhoff catheter insertion for peritoneal dialysis: A cost-effective approach.

PubMed

Lee, James; Mott, Nigel; Mahmood, Usman; Clouston, John; Summers, Kara; Nicholas, Pauline; Gois, Pedro Henrique França; Ranganathan, Dwarakanathan

2018-04-01

Radiological insertion of Tenckhoff catheters can be an alternative option for peritoneal dialysis access creation, as compared to surgical catheter insertion. This study will review the outcomes and complications of radiological Tenckhoff catheter insertion in a metropolitan renal service and compare costs between surgical and radiological insertion. Data were collected prospectively for all patients who had a Tenckhoff catheter insertion for peritoneal dialysis (PD) under radiological guidance at our hospital from May 2014 to November 2016. The type of catheter used and complications, including peri-catheter leak, exit site infection and peritonitis were reviewed. Follow-up data were also collected at points 3, 6 and 12 months from catheter insertion. Costing data were obtained from Queensland Health Electronic Reporting System (QHERS) data, average staff salaries and consumable contract price lists. In the 30-month evaluation period, 70 catheters were inserted. Two patients had an unsuccessful procedure due to the presence of abdominal adhesions. Seven patients had an episode of peri-catheter leak, and four patients had an exit site infection following catheter insertion. Peritonitis was observed in nine patients during the study period. The majority of patients (90%) remained on peritoneal dialysis at 3-month follow-up. The average costs of surgical and radiological insertion were noted to be AUD$7788.34 and AUD$1597.35, respectively. Radiological Tenckhoff catheter insertion for peritoneal dialysis appears to be an attractive and cost-effective option given less waiting periods for the procedure, the relatively low cost of insertion and comparable rates of complications. © 2017 The Royal Australian and New Zealand College of Radiologists.

Radial and circumferential flow surveys at the inlet and exit of the Space Shuttle Main Engine High Pressure Fuel Turbine Model

NASA Technical Reports Server (NTRS)

Hudson, S. T.; Bordelon, W. J., Jr.; Smith, A. W.; Ramachandran, N.

1995-01-01

The main objective of this test was to obtain detailed radial and circumferential flow surveys at the inlet and exit of the SSME High Pressure Fuel Turbine model using three-hole cobra probes, hot-film probes, and a laser velocimeter. The test was designed to meet several objectives. First, the techniques for making laser velocimeter, hot-film probe, and cobra probe measurements in turbine flows were developed and demonstrated. The ability to use the cobra probes to obtain static pressure and, therefore, velocity had to be verified; insertion techniques had to be established for the fragile hot-film probes; and a seeding method had to be established for the laser velocimetry. Once the measurement techniques were established, turbine inlet and exit velocity profiles, temperature profiles, pressure profiles, turbulence intensities, and boundary layer thicknesses were measured at the turbine design point. The blockage effect due to the model inlet and exit total pressure and total temperature rakes on the turbine performance was also studied. A small range of off-design points were run to obtain the profiles and to verify the rake blockage effects off-design. Finally, a range of different Reynolds numbers were run to study the effect of Reynolds number on the various measurements.

Simulation and analysis of traffic flow based on cellular automaton

NASA Astrophysics Data System (ADS)

Ren, Xianping; Liu, Xia

2018-03-01

In this paper, single-lane and two-lane traffic model are established based on cellular automaton. Different values of vehicle arrival rate at the entrance and vehicle departure rate at the exit are set to analyze their effects on density, average speed and traffic flow. If the road exit is unblocked, vehicles can pass through the road smoothly despite of the arrival rate at the entrance. If vehicles enter into the road continuously, the traffic condition is varied with the departure rate at the exit. To avoid traffic jam, reasonable vehicle departure rate should be adopted.

South Atlantic Anomaly Entry and Exit as Measured by the X-Ray Timing Explorer

NASA Technical Reports Server (NTRS)

Smith, Evan; Stark, Michael; Giles, Barry; Antunes, Sandy; Gawne, Bill

1996-01-01

The Rossi X-ray Timing Explorer (RXTE) carries instruments that must switch off high voltages (HV) when passing through the South Atlantic Anomaly (SAA). The High Energy X-ray Timing Experiment (HEXTE) contains a particle monitor that detects the increased particle flux associated with the SAA and autonomously reduces its voltage. The Proportional Counter Array (PCA) relies on uplinked predictions of SAA entry/exit times based on ephemeris data provided by the Flight Dynamics Facility. A third instrument, the All-Sky Monitor (ASM) also uses a predicted SAA model to reduce voltage when passing through the SAA. Data collected from the HEXTE particle monitor, as well as other instrument readings near the times of SAA entry/exit offer the potential for refining models of the boundaries of the SAA. The SAA has an increased particle flux which causes high rates of detection in the RXTE instruments designed to observe x-rays. The high counting rates could degrade the PCA if HV is not reduced during SAA passages. On the other hand, PCA downtime can be minimized and the science return can be optimized by having the best possible model of the SAA boundary. Thus, the PCA team planned an extensive effort during in-orbit checkout to utilize both the HEXTE particle monitor data and instrument counting rates to refine the model of the SAA boundary. The times of SAA entry and exit are compared with the definitive epemeris to determine the precise location (latitude and longitude) of the SAA boundary. Over time, the SAA and its perimeter were mapped. The RXTE Science Operations Center is continuously working to feed back the results of this effort into the science scheduling process, improving the SAA model as it affects the RXTE instruments, thus obtaining more accurate estimates of the SAA entry/exit times.

Computational study of haemodynamic effects of entry- and exit-tear coverage in a DeBakey type III aortic dissection: technical report.

PubMed

Karmonik, C; Bismuth, J; Shah, D J; Davies, M G; Purdy, D; Lumsden, A B

2011-08-01

Outcome prediction in DeBakey Type III aortic dissections (ADs) remains challenging. Large variations in AD morphology, physiology and treatment exist. Here, we investigate if computational fluid dynamics (CFD) can provide an initial understanding of pressure changes in an AD computational model when covering entry and exit tears and removing the intra-arterial septum (IS). A computational mesh was constructed from magnetic resonance images from one patient (one entrance and one exit tear) and CFD simulations performed (scenario #1). Additional meshes were derived by virtually (1) covering the exit tear (false lumen (FL) thrombus progression) (scenario #2), (2) covering the entrance tear (thoracic endovascular treatment, TEVAR) (scenario #3) and (3) completely removing the IS (fenestration) (scenario #4). Changes in flow patterns and pressures were quantified relative to the initial mesh. Systolic pressures increased for #2 (300 Pa increase) with largest inter-luminal differences distally (2500 Pa). In #3, false lumen pressure decreased essentially to zero. In #4, systolic pressure in combined lumen reduced from 2400 to 800 Pa. CFD results from computational models of a DeBakey type III AD representing separate coverage of entrance and exit tears correlated with clinical experience. The reported results present a preliminary look at a complex clinical problem. Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Factors associated with biosafety level-2 research workers' laboratory exit handwashing behaviors and glove removal compliance.

PubMed

Johnston, James D; Merrill, Ray M; Zimmerman, Grant C; Collingwood, Scott C; Reading, James C

2016-01-01

Biosafety level-2 laboratories are designated for work with human-derived samples or moderate-risk microorganisms that transmit primarily by direct contact exposures. Many laboratory procedures generate unseen droplets that contaminate workers' hands, equipment, and work surfaces. Workers' strict adherence to glove removal and handwashing is required prior to laboratory exit to prevent inadvertent transmission of pathogens to self or others. However, little is known about biosafety level-2 workers' compliance with these behaviors. In this article, glove removal and handwashing compliance upon laboratory exit were measured by direct observation of 93 biosafety level-2 research workers from 21 university laboratories. Participants completed a 41-item survey measuring social cognitive theory-based variables related to handwashing, self-reported compliance, and demographic factors. Survey items, observed exit frequency, and laboratory characteristics were evaluated for associations with handwashing compliance. Overall, observed glove removal and handwashing compliance upon laboratory exit were 43.0% (Standard Error [SE] = 2.3%), and 8.2% (SE = 1.2%), respectively, while workers' self-reported glove removal and handwashing compliance were 73.7% (SE = 3.6%) and 35.5% (SE = 4.1%), respectively. The average number of observed laboratory exits per hour was 2.8 for workers with any handwashing compliance vs. 5.4 for workers with no handwashing compliance (p = 0.0013). Among the cognitive variables, behavioral modeling by supervisors and coworkers had the strongest association with workers' compliance (slope = 3.5, SE = 1.3, p = 0.0113). Workers in laboratories with a written handwashing policy had higher compliance (Mean = 14.1%, SE = 5.9%) than workers in laboratories with no written policy (Mean = 1.1%, SE = 1.0%; p = 0.0488). Multi-faceted interventions that encourage modeling of the behavior by supervisors and coworkers, implementation of written handwashing policies, and efforts to reduce exit frequency by furnishing laboratories with necessary equipment and supplies may help improve compliance.

Reproducibility of an objective four-choice canine vision testing technique that assesses vision at differing light intensities.

PubMed

Annear, Matthew J; Gornik, Kara R; Venturi, Francesca L; Hauptman, Joe G; Bartoe, Joshua T; Petersen-Jones, Simon M

2013-09-01

The increasing importance of canine retinal dystrophy models means accurate vision testing is needed. This study was performed to evaluate a four-choice vision testing technique for any difference in outcome measures with repeated evaluations of the same dogs.   Four 11-month-old RPE65-deficient dogs. Vision was evaluated using a previously described four-choice vision testing device. Four evaluations were performed at 2-week intervals. Vision was assessed at six different white light intensities (bright through dim), and each eye was evaluated separately. The ability to select the one of the four exit tunnels that was open at the far end was assessed ('choice of exit') and recorded as correct or incorrect first tunnel choice. 'Time to exit' the device was also recorded. Both outcomes were analyzed for significance using anova. We hypothesized that performance would improve with repeated testing (more correct choices and more rapid time to exit). 'Choice of exit' did not vary significantly between each evaluation (P = 0.12), in contrast 'time to exit' increased significantly (P = 0.012), and showed greater variability in dim light conditions. We found no evidence to support the hypothesis that either measure of outcome worsened with repeated testing; in fact, the 'time to exit' outcome worsened rather than improved. The 'choice of exit' gave consistent results between trials. These outcome data indicate the importance of including a choice-based assessment of vision in addition to measurement of device transit time. © 2012 American College of Veterinary Ophthalmologists.

Conceptual design for an electron-beam heated hypersonic wind tunnel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lipinski, R.J.; Kensek, R.P.

1997-07-01

There is a need for hypersonic wind-tunnel testing at about mach 10 and above using natural air and simulating temperatures and pressures which are prototypic of flight at 50 km altitude or below. With traditional wind-tunnel techniques, gas cooling during expansion results in exit temperatures which are too low. Miles, et al., have proposed overcoming this difficulty by heating the air with a laser beam as it expands in the wind-tunnel nozzle. This report discusses an alternative option of using a high-power electron beam to heat the air as it expands. In the e-beam heating concept, the electron beam ismore » injected into the wind-tunnel nozzle near the exit and then is guided upstream toward the nozzle throat by a strong axial magnetic field. The beam deposits most of its power in the dense air near the throat where the expansion rate is greatest. A conceptual design is presented for a large-scale system which achieves Mach 14 for 0.1 seconds with an exit diameter of 2.8 meters. It requires 450 MW of electron beam power (5 MeV at 90 A). The guiding field is 500 G for most of the transport length and increases to 100 kG near the throat to converge the beam to a 1.0-cm diameter. The beam generator is a DC accelerator using a Marx bank (of capacitors) and a diode stack with a hot cathode. 14 refs. 38 figs., 9 tabs.« less

MINIVER upgrade for the AVID system. Volume 3: EXITS user's and input guide

NASA Technical Reports Server (NTRS)

Pond, J. E.; Schmitz, C. P.

1983-01-01

The successful design of thermal protection systems for vehicles operating in atmosphere and near-space environments requires accurate analyses of heating rate and temperature histories encountered along a trajectory. For preliminary design calculations, however, the requirement for accuracy must be tempered by the need for speed and versatility in computational tools used to determine thermal environments and structural thermal response. The MINIVER program was found to provide the proper balance between versatility, speed and accuracy for an aerothermal prediction tool. The advancement in computer aided design concepts at Langley Research Center (LaRC) in the past few years has made it desirable to incorporate the MINIVER program into the LaRC Advanced Vehicle Integrated Design, AVID, system. In order to effectively incorporate MINIVER into the AVID system, several changes to MINIVER were made. The thermal conduction options in MINIVER were removed and a new Explicit Interactive Thermal Structures (EXITS) code was developed. Many upgrades to the MINIVER code were made and a new Langley version of MINIVER called LANMIN was created.

Characterizing Particulate Matter Exfiltration Estimates for Alternative Cookstoves in a Village-Like Household in Rural Nepal.

PubMed

Soneja, Sutyajeet I; Tielsch, James M; Khatry, Subarna K; Zaitchik, Benjamin; Curriero, Frank C; Breysse, Patrick N

2017-11-01

Alternative stoves are an intervention option to reduce household air pollution. The amount of air pollution exiting homes when alternative stoves are utilized is not known. In this paper, particulate matter exfiltration estimates are presented for four types of alternative stoves within a village-like home, which was built to reflect the use of local materials and common size, in rural Nepal. Four alternative stoves with chimneys were examined, which included an alternative mud brick stove, original Envirofit G3355 model, manufacture altered Envirofit G3355, and locally altered Envirofit G3355. Multiple linear regression was utilized to determine estimates of PM2.5 exfiltration. Overall exfiltration fraction average (converted to a percent) for the four stoves were: alternative mud brick stove with chimney 56%, original Envirofit G3355 model with chimney 87%, manufacture altered Envirofit G3355 model with chimney 69%, and locally altered Envirofit G3355 model with chimney 69%. Alternative cookstoves resulted in higher overall average exfiltration due to direct and indirect ventilation relative to traditional, mud-based stoves. This contrast emphasizes the need for an improved understanding of the climate and health implications that are believed to come from implementing alternative stoves on a large scale and the resultant shift of exposure burden from indoors to outdoors.

Characterizing Particulate Matter Exfiltration Estimates for Alternative Cookstoves in a Village-Like Household in Rural Nepal

NASA Astrophysics Data System (ADS)

Soneja, Sutyajeet I.; Tielsch, James M.; Khatry, Subarna K.; Zaitchik, Benjamin; Curriero, Frank C.; Breysse, Patrick N.

2017-11-01

Alternative stoves are an intervention option to reduce household air pollution. The amount of air pollution exiting homes when alternative stoves are utilized is not known. In this paper, particulate matter exfiltration estimates are presented for four types of alternative stoves within a village-like home, which was built to reflect the use of local materials and common size, in rural Nepal. Four alternative stoves with chimneys were examined, which included an alternative mud brick stove, original Envirofit G3355 model, manufacture altered Envirofit G3355, and locally altered Envirofit G3355. Multiple linear regression was utilized to determine estimates of PM2.5 exfiltration. Overall exfiltration fraction average (converted to a percent) for the four stoves were: alternative mud brick stove with chimney 56%, original Envirofit G3355 model with chimney 87%, manufacture altered Envirofit G3355 model with chimney 69%, and locally altered Envirofit G3355 model with chimney 69%. Alternative cookstoves resulted in higher overall average exfiltration due to direct and indirect ventilation relative to traditional, mud-based stoves. This contrast emphasizes the need for an improved understanding of the climate and health implications that are believed to come from implementing alternative stoves on a large scale and the resultant shift of exposure burden from indoors to outdoors.

School Exits in the Milwaukee Parental Choice Program: Evidence of a Marketplace?

ERIC Educational Resources Information Center

Ford, Michael

2011-01-01

This article examines whether the large number of school exits from the Milwaukee school voucher program is evidence of a marketplace. Two logistic regression and multinomial logistic regression models tested the relation between the inability to draw large numbers of voucher students and the ability for a private school to remain viable. Data on…

Modeling an anode layer Hall thruster and its plume

NASA Astrophysics Data System (ADS)

Choi, Yongjun

This thesis consists of two parts: a study of the D55 Hall thruster channel using a hydrodynamic model; and particle simulations of plasma plume flow from the D55 Hall thruster. The first part of this thesis investigates the xenon plasma properties within the D55 thruster channel using a hydrodynamic model. The discharge voltage (V) and current (I) characteristic of the D55 Hall thruster are studied. The hydrodynamic model fails to accurately predict the V-I characteristics. This analysis shows that the model needs to be improved. Also, the hydrodynamic model is used to simulate the plasma flow within the D55 Hall thruster. This analysis is performed to investigate the plasma properties of the channel exit. It is found that the hydrodynamic model is very sensitive to initial conditions, and fails to simulate the complete domain of the D55 Hall thruster. However, the model successfully calculates the channel domain of the D55 Hall thruster. The results show that, at the thruster exit, the plasma density has a maximum value while the ion velocity has a minimum at the channel center. Also, the results show that the flow angle varies almost linearly across the exit plane and increases from the center to the walls. Finally, the hydrodynamic model results are used to estimate the plasma properties at the thruster nozzle exit. The second part of the thesis presents two dimensional axisymmetric simulations of xenon plasma plume flow fields from the D55 anode layer Hall thruster. A hybrid particle-fluid method is used for the simulations. The magnetic field near the Hall thruster exit is included in the calculation. The plasma properties obtained from the hydrodynamic model are used to determine boundary conditions for the simulations. In these simulations, the Boltzmann model and a detailed fluid model are used to compute the electron properties, the direct simulation Monte Carlo method models the collisions of heavy particles, and the Particle-In-Cell method models the transport of ions in an electric field. The accuracy of the simulation is assessed through comparison with various sets of measured data. It is found that a magnetic field significantly affects the profile of the plasma in the Detailed model. For instance, the plasma potential decreases more rapidly with distance from the thruster in the presence of a magnetic field. Results predicted by the Detailed model with the magnetic field are in better agreement with experimental data than those obtained with other models investigated.

Conformity and Dissonance in Generalized Voter Models

NASA Astrophysics Data System (ADS)

Page, Scott E.; Sander, Leonard M.; Schneider-Mizell, Casey M.

2007-09-01

We generalize the voter model to include social forces that produce conformity among voters and avoidance of cognitive dissonance of opinions within a voter. The time for both conformity and consistency (which we call the exit time) is, in general, much longer than for either process alone. We show that our generalized model can be applied quite widely: it is a form of Wright's island model of population genetics, and is related to problems in the physical sciences. We give scaling arguments, numerical simulations, and analytic estimates for the exit time for a range of relative strengths in the tendency to conform and to avoid dissonance.

On the Scaling Laws for Jet Noise in Subsonic and Supersonic Flow

NASA Technical Reports Server (NTRS)

Vu, Bruce; Kandula, Max

2003-01-01

The scaling laws for the simulation of noise from subsonic and ideally expanded supersonic jets are examined with regard to their applicability to deduce full scale conditions from small-scale model testing. Important parameters of scale model testing for the simulation of jet noise are identified, and the methods of estimating full-scale noise levels from simulated scale model data are addressed. The limitations of cold-jet data in estimating high-temperature supersonic jet noise levels are discussed. It is shown that the jet Mach number (jet exit velocity/sound speed at jet exit) is a more general and convenient parameter for noise scaling purposes than the ratio of jet exit velocity to ambient speed of sound. A similarity spectrum is also proposed, which accounts for jet Mach number, angle to the jet axis, and jet density ratio. The proposed spectrum reduces nearly to the well-known similarity spectra proposed by Tam for the large-scale and the fine-scale turbulence noise in the appropriate limit.

Theoretical evaluation of a V/STOL fighter model utilizing the PAN AIR code

NASA Technical Reports Server (NTRS)

Howell, G. A.; Bhateley, I. C.

1982-01-01

The PAN AIR computer code was investigated as a tool for predicting closely coupled aerodynamic and propulsive flowfields of arbitrary configurations. The NASA/Ames V/STOL fighter model, a configuration of complex geometry, was analyzed with the PAN AIR code. A successful solution for this configuration was obtained when the nozzle exit was treated as an impermeable surface and no wakes were included around the nozzle exit. When separated flow was simulated from the end of the nacelle, requiring the use of wake networks emanating from the nozzle exit, a number of problems were encountered. A circular body nacelle model was used to investigate various techniques for simulating the exhaust plume in PAN AIR. Several approaches were tested and eliminated because they could not correctly simulate the interference effects. Only one plume modeling technique gave good results. A PAN AIR computation that used a plume shape and inflow velocities obtained from the Navier-Stokes solution for the plume produced results for the effects of power that compared well with experimental data.

Thermal regime, predation danger and the early marine exit of sockeye salmon Oncorhynchus nerka.

PubMed

Katinic, P J; Patterson, D A; Ydenberg, R C

2015-01-01

Marine exit timing of sockeye salmon Oncorhynchus nerka populations on the Haida Gwaii Archipelago, British Columbia, Canada, is described, with specific focus on Copper Creek. Marine exit in Copper Creek occurs > 130 days prior to spawning, one of the longest adult freshwater residence periods recorded for any O. nerka population. Copper Creek presents an easy upstream migration, with mild water temperatures (7 to 14°  C), short distance (13·1 km) and low elevation gain (41 m) to the lake where fish hold prior to spawning. An energetic model estimates that <1% of the initial energy reserve is required for upstream migration, compared with 62% for lake holding and 38% for reproductive development. Historical records suggest that it is unlikely that water temperature in any of the O.nerka streams in Haida Gwaii has ever exceeded the presumed temperature threshold (19° C) for early marine exit. Although it is not impossible that the thermal tolerance of Copper Creek O.nerka is very low, the data presented here appear inconsistent with thermal avoidance as an explanation for the early marine exit timing in Copper Creek and in three other populations on the archipelago with early marine exit. © 2014 The Fisheries Society of the British Isles.

Long-term effects of psychosocial work stress in midlife on health functioning after labor market exit--results from the GAZEL study.

PubMed

Wahrendorf, Morten; Sembajwe, Grace; Zins, Marie; Berkman, Lisa; Goldberg, Marcel; Siegrist, Johannes

2012-07-01

To study long-term effects of psychosocial work stress in mid-life on health functioning after labor market exit using two established work stress models. In the frame of the prospective French Gazel cohort study, data on psychosocial work stress were assessed using the full questionnaires measuring the demand-control-support model (in 1997 and 1999) and the effort-reward imbalance model (in 1998). In 2007, health functioning was assessed, using the Short Form 36 mental and physical component scores. Multivariate regressions were calculated to predict health functioning in 2007, controlling for age, gender, social position, and baseline self-perceived health. Consistent effects of both work stress models and their single components on mental and physical health functioning during retirement were observed. Effects remained significant after adjustment including baseline self-perceived health. Whereas the predictive power of both work stress models was similar in the case of the physical composite score, in the case of the mental health score, values of model fit were slightly higher for the effort-reward imbalance model (R(2): 0.13) compared with the demand-control model (R²: 0.11). Findings underline the importance of working conditions in midlife not only for health in midlife but also for health functioning after labor market exit.

Mixing of Supersonic Streams

NASA Technical Reports Server (NTRS)

Hawk, C. W.; Landrum, D. B.; Muller, S.; Turner, M.; Parkinson, D.

1998-01-01

The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ingested air for successful operation in the ramjet and scramjet modes. It is desirable to delay this mixing process in the air-augmented mode of operation present during low speed flight. A model of the Strutjet device has been built and is undergoing test to investigate the mixing of the streams as a function of distance from the Strutjet exit plane during simulated low speed flight conditions. Cold flow testing of a 1/6 scale Strutjet model is underway and nearing completion. Planar Laser Induced Fluorescence (PLIF) diagnostic methods are being employed to observe the mixing of the turbine exhaust gas with the gases from both the primary rockets and the ingested air simulating low speed, air augmented operation of the RBCC. The ratio of the pressure in the turbine exhaust duct to that in the rocket nozzle wall at the point of their intersection is the independent variable in these experiments. Tests were accomplished at values of 1.0, 1.5 and 2.0 for this parameter. Qualitative results illustrate the development of the mixing zone from the exit plane of the model to a distance of about 19 equivalent rocket nozzle exit diameters downstream. These data show the mixing to be confined in the vertical plane for all cases, The lateral expansion is more pronounced at a pressure ratio of 1.0 and suggests that mixing with the ingested flow would be likely beginning at a distance of 7 nozzle exit diameters downstream of the nozzle exit plane.

Generalized Fluid System Simulation Program, Version 6.0

NASA Technical Reports Server (NTRS)

Majumdar, A. K.; LeClair, A. C.; Moore, R.; Schallhorn, P. A.

2016-01-01

The Generalized Fluid System Simulation Program (GFSSP) is a general purpose computer program for analyzing steady state and time-dependent flow rates, pressures, temperatures, and concentrations in a complex flow network. The program is capable of modeling real fluids with phase changes, compressibility, mixture thermodynamics, conjugate heat transfer between solid and fluid, fluid transients, pumps, compressors, and external body forces such as gravity and centrifugal. The thermofluid system to be analyzed is discretized into nodes, branches, and conductors. The scalar properties such as pressure, temperature, and concentrations are calculated at nodes. Mass flow rates and heat transfer rates are computed in branches and conductors. The graphical user interface allows users to build their models using the 'point, drag, and click' method; the users can also run their models and post-process the results in the same environment. Two thermodynamic property programs (GASP/WASP and GASPAK) provide required thermodynamic and thermophysical properties for 36 fluids: helium, methane, neon, nitrogen, carbon monoxide, oxygen, argon, carbon dioxide, fluorine, hydrogen, parahydrogen, water, kerosene (RP-1), isobutene, butane, deuterium, ethane, ethylene, hydrogen sulfide, krypton, propane, xenon, R-11, R-12, R-22, R-32, R-123, R-124, R-125, R-134A, R-152A, nitrogen trifluoride, ammonia, hydrogen peroxide, and air. The program also provides the options of using any incompressible fluid with constant density and viscosity or ideal gas. The users can also supply property tables for fluids that are not in the library. Twenty-four different resistance/source options are provided for modeling momentum sources or sinks in the branches. These options include pipe flow, flow through a restriction, noncircular duct, pipe flow with entrance and/or exit losses, thin sharp orifice, thick orifice, square edge reduction, square edge expansion, rotating annular duct, rotating radial duct, labyrinth seal, parallel plates, common fittings and valves, pump characteristics, pump power, valve with a given loss coefficient, Joule-Thompson device, control valve, heat exchanger core, parallel tube, and compressible orifice. The program has the provision of including additional resistance options through User Subroutines. GFSSP employs a finite volume formulation of mass, momentum, and energy conservation equations in conjunction with the thermodynamic equations of state for real fluids as well as energy conservation equations for the solid. The system of equations describing the fluid network is solved by a hybrid numerical method that is a combination of the Newton-Raphson and successive substitution methods. The application and verification of the code has been demonstrated through 30 example problems.

Modeling Film-Coolant Flow Characteristics at the Exit of Shower-Head Holes

NASA Technical Reports Server (NTRS)

Garg, Vijay K.; Gaugler, R. E. (Technical Monitor)

2000-01-01

The coolant flow characteristics at the hole exits of a film-cooled blade are derived from an earlier analysis where the hole pipes and coolant plenum were also discretized. The blade chosen is the VKI rotor with three staggered rows of shower-head holes. The present analysis applies these flow characteristics at the shower-head hole exits. A multi-block three-dimensional Navier-Stokes code with Wilcox's k-omega model is used to compute the heat transfer coefficient on the film-cooled turbine blade. A reasonably good comparison with the experimental data as well as with the more complete earlier analysis where the hole pipes and coolant plenum were also gridded is obtained. If the 1/7th power law is assumed for the coolant flow characteristics at the hole exits, considerable differences in the heat transfer coefficient on the blade surface, specially in the leading-edge region, are observed even though the span-averaged values of h (heat transfer coefficient based on T(sub o)-T(sub w)) match well with the experimental data. This calls for span-resolved experimental data near film-cooling holes on a blade for better validation of the code.

Numerical analysis of two and three dimensional buoyancy driven water-exit of a circular cylinder

NASA Astrophysics Data System (ADS)

Moshari, Shahab; Nikseresht, Amir Hossein; Mehryar, Reza

2014-06-01

With the development of the technology of underwater moving bodies, the need for developing the knowledge of surface effect interaction of free surface and underwater moving bodies is increased. Hence, the two-phase flow is a subject which is interesting for many researchers all around the world. In this paper, the non-linear free surface deformations which occur during the water-exit of a circular cylinder due to its buoyancy are solved using finite volume discretization based code, and using Volume of Fluid (VOF) scheme for solving two phase flow. Dynamic mesh model is used to simulate dynamic motion of the cylinder. In addition, the effect of cylinder mass in presence of an external force is studied. Moreover, the oblique exit and entry of a circular cylinder with two exit angles is simulated. At last, water-exit of a circular cylinder in six degrees of freedom is simulated in 3D using parallel processing. The simulation errors of present work (using VOF method) for maximum velocity and height of a circular cylinder are less than the corresponding errors of level set method reported by previous researchers. Oblique exit shows interesting results; formation of waves caused by exit of the cylinder, wave motion in horizontal direction and the air trapped between the waves are observable. In 3D simulation the visualization of water motion on the top surface of the cylinder and the free surface breaking on the front and back faces of the 3D cylinder at the exit phase are observed which cannot be seen in 2D simulation. Comparing the results, 3D simulation shows better agreement with experimental data, specially in the maximum height position of the cylinder.

Comprehensive schoolteachers at risk of early exit from work.

PubMed

Mykletun, R J; Mykletun, A

1999-01-01

Risk of early exit from work for teachers was operationalized as high burnout scores, working part-time due to heavy burden and illness or working part-time while also receiving partial disability pension. Data were collected by mailed questionnaires in a cross-sectional study to a random sample of Norwegian comprehensive schoolteachers, response rate = 86% (N = 1860 valid cases). High age increased the risk of early exit from work, but for cynicism the age effect disappeared when sense of competence and stress were introduced in the regression model. Age had no effect for low professional efficacy. Sense of competence effected burnout, but actual competence level and the gap between actual competence and teaching obligations did not. Stress effected all measures of risk of early exit, especially exhaustion. Change as stress factor increased the exhaustion scores, and were also relevant to risk of having a part-time position, and/or partial disability pension.

Computer code for preliminary sizing analysis of axial-flow turbines

NASA Technical Reports Server (NTRS)

Glassman, Arthur J.

1992-01-01

This mean diameter flow analysis uses a stage average velocity diagram as the basis for the computational efficiency. Input design requirements include power or pressure ratio, flow rate, temperature, pressure, and rotative speed. Turbine designs are generated for any specified number of stages and for any of three types of velocity diagrams (symmetrical, zero exit swirl, or impulse) or for any specified stage swirl split. Exit turning vanes can be included in the design. The program output includes inlet and exit annulus dimensions, exit temperature and pressure, total and static efficiencies, flow angles, and last stage absolute and relative Mach numbers. An analysis is presented along with a description of the computer program input and output with sample cases. The analysis and code presented herein are modifications of those described in NASA-TN-D-6702. These modifications improve modeling rigor and extend code applicability.

A dual two dimensional electronic portal imaging device transit dosimetry model based on an empirical quadratic formalism

PubMed Central

Metwaly, M; Glegg, M; Baggarley, S P; Elliott, A

2015-01-01

Objective: This study describes a two dimensional electronic portal imaging device (EPID) transit dosimetry model that can predict either: (1) in-phantom exit dose, or (2) EPID transit dose, for treatment verification. Methods: The model was based on a quadratic equation that relates the reduction in intensity to the equivalent path length (EPL) of the attenuator. In this study, two sets of quadratic equation coefficients were derived from calibration dose planes measured with EPID and ionization chamber in water under reference conditions. With two sets of coefficients, EPL can be calculated from either EPID or treatment planning system (TPS) dose planes. Consequently, either the in-phantom exit dose or the EPID transit dose can be predicted from the EPL. The model was tested with two open, five wedge and seven sliding window prostate and head and neck intensity-modulated radiation therapy (IMRT) fields on phantoms. Results were analysed using absolute gamma analysis (3%/3 mm). Results: The open fields gamma pass rates were >96.8% for all comparisons. For wedge and IMRT fields, comparisons between predicted and TPS-computed in-phantom exit dose resulted in mean gamma pass rate of 97.4% (range, 92.3–100%). As for the comparisons between predicted and measured EPID transit dose, the mean gamma pass rate was 97.5% (range, 92.6–100%). Conclusion: An EPID transit dosimetry model that can predict in-phantom exit dose and EPID transit dose was described and proven to be valid. Advances in knowledge: The described model is practical, generic and flexible to encourage widespread implementation of EPID dosimetry for the improvement of patients' safety in radiotherapy. PMID:25969867

Simulation of stochastic diffusion via first exit times

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lötstedt, Per, E-mail: perl@it.uu.se; Meinecke, Lina, E-mail: lina.meinecke@it.uu.se

2015-11-01

In molecular biology it is of interest to simulate diffusion stochastically. In the mesoscopic model we partition a biological cell into unstructured subvolumes. In each subvolume the number of molecules is recorded at each time step and molecules can jump between neighboring subvolumes to model diffusion. The jump rates can be computed by discretizing the diffusion equation on that unstructured mesh. If the mesh is of poor quality, due to a complicated cell geometry, standard discretization methods can generate negative jump coefficients, which no longer allows the interpretation as the probability to jump between the subvolumes. We propose a methodmore » based on the mean first exit time of a molecule from a subvolume, which guarantees positive jump coefficients. Two approaches to exit times, a global and a local one, are presented and tested in simulations on meshes of different quality in two and three dimensions.« less

Simulation of stochastic diffusion via first exit times

PubMed Central

Lötstedt, Per; Meinecke, Lina

2015-01-01

In molecular biology it is of interest to simulate diffusion stochastically. In the mesoscopic model we partition a biological cell into unstructured subvolumes. In each subvolume the number of molecules is recorded at each time step and molecules can jump between neighboring subvolumes to model diffusion. The jump rates can be computed by discretizing the diffusion equation on that unstructured mesh. If the mesh is of poor quality, due to a complicated cell geometry, standard discretization methods can generate negative jump coefficients, which no longer allows the interpretation as the probability to jump between the subvolumes. We propose a method based on the mean first exit time of a molecule from a subvolume, which guarantees positive jump coefficients. Two approaches to exit times, a global and a local one, are presented and tested in simulations on meshes of different quality in two and three dimensions. PMID:26600600

Nonlinear Modeling and Control of a Propellant Mixer

NASA Technical Reports Server (NTRS)

Barbieri, Enrique; Richter, Hanz; Figueroa, Fernando

2003-01-01

A mixing chamber used in rocket engine combustion testing at NASA Stennis Space Center is modeled by a second order nonlinear MIMO system. The mixer is used to condition the thermodynamic properties of cryogenic liquid propellant by controlled injection of the same substance in the gaseous phase. The three inputs of the mixer are the positions of the valves regulating the liquid and gas flows at the inlets, and the position of the exit valve regulating the flow of conditioned propellant. The outputs to be tracked and/or regulated are mixer internal pressure, exit mass flow, and exit temperature. The outputs must conform to test specifications dictated by the type of rocket engine or component being tested downstream of the mixer. Feedback linearization is used to achieve tracking and regulation of the outputs. It is shown that the system is minimum-phase provided certain conditions on the parameters are satisfied. The conditions are shown to have physical interpretation.

Theoretical analysis of an augmentor wing for a VTOL fighter

NASA Technical Reports Server (NTRS)

Dillenius, M. F. E.; Mendenhall, M. R.

1979-01-01

A method based on potential flow theory was developed for predicting forces and moments acting on augmentor wings for prescribed ejector jet characteristics. A three dimensional nonplanar vortex lattice is laid out on the chordal planes of the augmentor wing components. Jet induced effects are included in the boundary condition from which the horseshoe vortex strengths are obtained. The jet within the diffusor is made to expand from the primary nozzles to the diffusor exit and is represented by a distribution of vorticity on the jet boundary to provide proper entrainment. The jet downstream of the diffusor exit is modeled by a vorticity distribution and blockage panels and its centerline location and spreading rate are taken from experimental data. The vortex lattice and jet models are used in an iterative manner until the predicted diffusor exit velocity matches the specified one. Some comparisons with available data show good agreement at lower power settings.

Computer modeling of fan-exit-splitter spacing effects on F100 response to distortion

NASA Technical Reports Server (NTRS)

Shaw, M.; Murdoch, R. W.

1982-01-01

The distortion response of the F100(3) engine was effected by the fan exit splitter configuration. The sensitivity for a proximate splitter fan is calculated to be slightly greater than a remote splitter configuration with identical airfoils. Predicted response was based upon a multiple segment parallel compressor Model modified to include a bypass ratio representation that effects the performance characteristics of the last rotor and intermediate case struts. The predicted distortion response required an accurate definition of row pre- and post-stall undistorted operation.

A model for reducing health care employee turnover.

PubMed

Nowak, Paul; Holmes, Gary; Murrow, Jim

2010-01-01

Explaining the rationale as to why employees leave their jobs has led to many different strategies to retain employees. The model presented here seeks to explain why employees choose to stay or to leave their place of employment. The information from the analysis will provide managers with well-tested tools to reduce turnover and to ascertain what employees value from their work environment in order to help the organization to retain those employees. The model identifies key factors that management can utilize to provide barriers to exit and retain professional employees in their health care units. Recommendations are provided that reward loyalty and build barriers to exit.

Factors associated with re-entry to out-of-home care among children in England.

PubMed

Mc Grath-Lone, Louise; Dearden, Lorraine; Harron, Katie; Nasim, Bilal; Gilbert, Ruth

2017-01-01

Exiting and re-entering out-of-home care (OHC) is considered a disruption to permanence which may have long-lasting, negative consequences for children due to a lack of stability and continuity. Each year approximately one-third of children in OHC in England exit, but information is lacking on rates of re-entries and associated factors. Using national administrative data, we calculated rates of re-entry among children exiting OHC from 2007 to 2012, identified key child and care factors associated with re-entry using Cox proportional hazards modelling, and developed a simple probability calculator to estimate which groups of children are most likely to re-enter OHC within three months. Between 2007 and 2012 re-entries to OHC in England decreased (from 23.3% to 14.4% within one year of exit, p<0.001), possibly due to concurrent changes in the way children exited OHC. Overall, more than one-third of children exiting OHC in 2008 re-entered within five years (35.3%, N=4076), but rates of re-entry varied by child and care characteristics including age, ethnicity, mode of exit, and placement stability. Based on these associated factors, we developed a calculator that can estimate the likelihood of rapid re-entry to OHC for a group of children and could be used by social care practitioners or service planners. Our findings provide insight into which groups of children are most likely to re-enter OHC, who may benefit from additional support or ongoing monitoring. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Evaluation of Sensor Technology to Detect Fall Risk and Prevent Falls in Acute Care.

PubMed

Potter, Patricia; Allen, Kelly; Costantinou, Eileen; Klinkenberg, William Dean; Malen, Jill; Norris, Traci; O'Connor, Elizabeth; Roney, Wilhemina; Tymkew, Heidi Hahn; Wolf, Laurie

2017-08-01

Sensor technology that dynamically identifies hospitalized patients' fall risk and detects and alerts nurses of high-risk patients' early exits out of bed has potential for reducing fall rates and preventing patient harm. During Phase 1 (August 2014-January 2015) of a previously reported performance improvement project, an innovative depth sensor was evaluated on two inpatient medical units to study fall characteristics. In Phase 2 (April 2015-January 2016), a combined depth and bed sensor system designed to assign patient fall probability, detect patient bed exits, and subsequently prevent falls was evaluated. Fall detection depth sensors remained in place on two medicine units; bed sensors used to detect patient bed exits were added on only one of the medicine units. Fall rates and fall with injury rates were evaluated on both units. During Phase 2, the designated evaluation unit had 14 falls, for a fall rate of 2.22 per 1,000 patient-days-a 54.1% reduction compared with the Phase 1 fall rate. The difference in rates from Phase 1 to Phase 2 was statistically significant (z = 2.20; p = 0.0297). The comparison medicine unit had 30 falls-a fall rate of 4.69 per 1,000 patient-days, representing a 57.9% increase as compared with Phase 1. A fall detection sensor system affords a level of surveillance that standard fall alert systems do not have. Fall prevention remains a complex issue, but sensor technology is a viable fall prevention option. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Materials property definition and generation for carbon-carbon and carbon phenolic materials

NASA Technical Reports Server (NTRS)

Canfield, A. R.; Mathis, J. R.; Starrett, H. S.; Koenig, J. R.

1987-01-01

A data base program to generate statistically significant material-property data for carbon-carbon and carbon phenolic materials to be used in designs of Space Shuttle is described. The program, which will provide data necessary for thermal and stress modeling of Shuttle nozzle and exit cone structures, includes evaluation of tension, compression, shear strength, shear modulus, thermal expansion, thermal conductivity, permeability, and emittance for both materials; the testing of carbon phenolic materials also includes CTE, off-gassing, pyrolysis, and RTG. Materials to be tested will be excised from Space Shuttle inlet, throat, and exit cone billets and modified involute carbon-carbon exit cones; coprocessed blocks, panels, and cylinders will also be tested.

Calcium Signaling and Meiotic Exit at Fertilization in Xenopus Egg

PubMed Central

Tokmakov, Alexander A.; Stefanov, Vasily E.; Iwasaki, Tetsushi; Sato, Ken-Ichi; Fukami, Yasuo

2014-01-01

Calcium is a universal messenger that mediates egg activation at fertilization in all sexually reproducing species studied. However, signaling pathways leading to calcium generation and the mechanisms of calcium-induced exit from meiotic arrest vary substantially among species. Here, we review the pathways of calcium signaling and the mechanisms of meiotic exit at fertilization in the eggs of the established developmental model, African clawed frog, Xenopus laevis. We also discuss calcium involvement in the early fertilization-induced events in Xenopus egg, such as membrane depolarization, the increase in intracellular pH, cortical granule exocytosis, cortical contraction, contraction wave, cortical rotation, reformation of the nuclear envelope, sperm chromatin decondensation and sister chromatid segregation. PMID:25322156

Escape problem under stochastic volatility: The Heston model

NASA Astrophysics Data System (ADS)

Masoliver, Jaume; Perelló, Josep

2008-11-01

We solve the escape problem for the Heston random diffusion model from a finite interval of span L . We obtain exact expressions for the survival probability (which amounts to solving the complete escape problem) as well as for the mean exit time. We also average the volatility in order to work out the problem for the return alone regardless of volatility. We consider these results in terms of the dimensionless normal level of volatility—a ratio of the three parameters that appear in the Heston model—and analyze their form in several asymptotic limits. Thus, for instance, we show that the mean exit time grows quadratically with large spans while for small spans the growth is systematically slower, depending on the value of the normal level. We compare our results with those of the Wiener process and show that the assumption of stochastic volatility, in an apparently paradoxical way, increases survival and prolongs the escape time. We finally observe that the model is able to describe the main exit-time statistics of the Dow-Jones daily index.

User experiences with clinical social franchising: qualitative insights from providers and clients in Ghana and Kenya.

PubMed

Sieverding, Maia; Briegleb, Christina; Montagu, Dominic

2015-02-01

Clinical social franchising is a rapidly growing delivery model in private healthcare markets in low- and middle-income countries. Despite this growth, little is known about providers' perceptions of the benefits and challenges of social franchising or clients' reasons for choosing franchised facilities over other healthcare options. We examine these questions in the context of three social franchise networks in Ghana and Kenya. We conducted in-depth interviews with a purposive sample of providers from the BlueStar Ghana, and Amua and Tunza networks in Kenya. We also conducted qualitative exit interviews with female clients who were leaving franchised facilities after a visit for a reproductive or child health reason. The total sample consists of 47 providers and 47 clients across the three networks. Providers perceived the main benefits of participation in a social franchise network to be training opportunities and access to a consistent supply of low-cost family planning commodities; few providers mentioned branding as a benefit of participation. Although most providers said that client flows for franchised services increased after joining the network, they did not associate this with improved finances for their facility. Clients overwhelmingly cited the quality of the client-provider relationship as their main motivation for attending the franchise facility. Recognition of the franchise brand was low among clients who were exiting a franchised facility. The most important benefit of social franchise programs to both providers and their clients may have more to do with training on business practices, patient counseling and customer service, than with subsidies, technical input, branding or clinical support. This finding may lead to a reconsideration of how franchise programs interact with both their member clinics and the larger health-seeking communities they serve.

Supersonic Injection of Aerated Liquid Jet

NASA Astrophysics Data System (ADS)

Choudhari, Abhijit; Sallam, Khaled

2016-11-01

A computational study of the exit flow of an aerated two-dimensional jet from an under-expanded supersonic nozzle is presented. The liquid sheet is operating within the annular flow regime and the study is motivated by the application of supersonic nozzles in air-breathing propulsion systems, e.g. scramjet engines, ramjet engines and afterburners. The simulation was conducted using VOF model and SST k- ω turbulence model. The test conditions included: jet exit of 1 mm and mass flow rate of 1.8 kg/s. The results show that air reaches transonic condition at the injector exit due to the Fanno flow effects in the injector passage. The aerated liquid jet is alternately expanded by Prandtl-Meyer expansion fan and compressed by oblique shock waves due to the difference between the back (chamber) pressure and the flow pressure. The process then repeats itself and shock (Mach) diamonds are formed at downstream of injector exit similar to those typical of exhaust plumes of propulsion system. The present results, however, indicate that the flow field of supersonic aerated liquid jet is different from supersonic gas jets due to the effects of water evaporation from the liquid sheet. The contours of the Mach number, static pressure of both cases are compared to the theory of gas dynamics.

Noise Reduction Design of the Volute for a Centrifugal Compressor

NASA Astrophysics Data System (ADS)

Song, Zhen; Wen, Huabing; Hong, Liangxing; Jin, Yudong

2017-08-01

In order to effectively control the aerodynamic noise of a compressor, this paper takes into consideration a marine exhaust turbocharger compressor as a research object. According to the different design concept of volute section, tongue and exit cone, six different volute models were established. The finite volume method is used to calculate the flow field, whiles the finite element method is used for the acoustic calculation. Comparison and analysis of different structure designs from three aspects: noise level, isentropic efficiency and Static pressure recovery coefficient. The results showed that under the concept of volute section model 1 yielded the best result, under the concept of tongue analysis model 3 yielded the best result and finally under exit cone analysis model 6 yielded the best results.

Asymptotic problems for stochastic partial differential equations

NASA Astrophysics Data System (ADS)

Salins, Michael

Stochastic partial differential equations (SPDEs) can be used to model systems in a wide variety of fields including physics, chemistry, and engineering. The main SPDEs of interest in this dissertation are the semilinear stochastic wave equations which model the movement of a material with constant mass density that is exposed to both determinstic and random forcing. Cerrai and Freidlin have shown that on fixed time intervals, as the mass density of the material approaches zero, the solutions of the stochastic wave equation converge uniformly to the solutions of a stochastic heat equation, in probability. This is called the Smoluchowski-Kramers approximation. In Chapter 2, we investigate some of the multi-scale behaviors that these wave equations exhibit. In particular, we show that the Freidlin-Wentzell exit place and exit time asymptotics for the stochastic wave equation in the small noise regime can be approximated by the exit place and exit time asymptotics for the stochastic heat equation. We prove that the exit time and exit place asymptotics are characterized by quantities called quasipotentials and we prove that the quasipotentials converge. We then investigate the special case where the equation has a gradient structure and show that we can explicitly solve for the quasipotentials, and that the quasipotentials for the heat equation and wave equation are equal. In Chapter 3, we study the Smoluchowski-Kramers approximation in the case where the material is electrically charged and exposed to a magnetic field. Interestingly, if the system is frictionless, then the Smoluchowski-Kramers approximation does not hold. We prove that the Smoluchowski-Kramers approximation is valid for systems exposed to both a magnetic field and friction. Notably, we prove that the solutions to the second-order equations converge to the solutions of the first-order equation in an Lp sense. This strengthens previous results where convergence was proved in probability.

Phase 2: HGM air flow tests in support of HEX vane investigation

NASA Technical Reports Server (NTRS)

Cox, G. B., Jr.; Steele, L. L.; Eisenhart, D. W.

1993-01-01

Following the start of SSME certification testing for the Pratt and Whitney Alternate Turbopump Development (ATD) High Pressure Oxidizer Turbopump (HPOTP), cracking of the leading edge of the inner HEX vane was experienced. The HEX vane, at the inlet of the oxidizer bowl in the Hot Gas Manifold (HGM), accepts the HPOTP turbine discharge flow and turns it toward the Gaseous Oxidizer Heat Exchanger (GOX HEX) coil. The cracking consistently initiated over a specific circumferential region of the hex vane, with other circumferential locations appearing with increased run time. Since cracking had not to date been seen with the baseline HPOTP, a fluid-structural interaction involving the ATD HPOTP turbine exit flowfield and the HEX inner vane was suspected. As part of NASA contract NAS8-36801, Pratt and Whitney conducted air flow tests of the ATD HPOTP turbine turnaround duct flowpath in the MSFC Phase 2 HGM air flow model. These tests included HEX vane strain gages and additional fluctuating pressure gages in the turnaround duct and HEX vane flowpath area. Three-dimensional flow probe measurements at two stations downstream of the turbine simulator exit plane were also made. Modifications to the HPOTP turbine simulator investigated the effects on turbine exit flow profile and velocity components, with the objective of reproducing flow conditions calculated for the actual ATD HPOTP hardware. Testing was done at the MSFC SSME Dynamic Fluid Air Flow (Dual-Leg) Facility, at air supply pressures between 50 and 250 psia. Combinations of turbine exit Mach number and pressure level were run to investigate the effect of flow regime. Information presented includes: (1) Descriptions of turbine simulator modifications to produce the desired flow environment; (2) Types and locations for instrumentation added to the flow model for improved diagnostic capability; (3) Evaluation of the effect of changes to the turbine simulator flowpath on the turbine exit flow environment; and (4) Comparison of the experimental turbine exit flow environment to the environment calculated for the ATD HPOTP.

Wind tunnel test results of a 1/8-scale fan-in-wing model

NASA Technical Reports Server (NTRS)

Wilson, John C.; Gentry, Garl L.; Gorton, Susan A.

1996-01-01

A 1/8-scale model of a fan-in-wing concept considered for development by Grumman Aerospace Corporation for the U.S. Army was tested in the Langley 14- by 22-Foot Subsonic Tunnel. Hover testing, which included height above a pressure-instrumented ground plane, angle of pitch, and angle of roll for a range of fan thrust, was conducted in a model preparation area near the tunnel. The air loads and surface pressures on the model were measured for several configurations in the model preparation area and in the tunnel. The major hover configuration change was varying the angles of the vanes attached to the exit of the fans for producing propulsive force. As the model height above the ground was decreased, there was a significant variation of thrust-removed normal force with constant fan speed. The greatest variation was generally for the height-to-fan exit diameter ratio of less than 2.5; the variation was reduced by deflecting fan exit flow outboard with the vanes. In the tunnel angles of pitch and sideslip, height above the tunnel floor, and wind speed were varied for a range of fan thrust and different vane angle configurations. Other configuration features such as flap deflections and tail incidence were evaluated as well. Though the V-tail empennage provided an increase in static longitudinal stability, the total model configuration remained unstable.

A reduced theoretical model for estimating condensation effects in combustion-heated hypersonic tunnel

NASA Astrophysics Data System (ADS)

Lin, L.; Luo, X.; Qin, F.; Yang, J.

2018-03-01

As one of the combustion products of hydrocarbon fuels in a combustion-heated wind tunnel, water vapor may condense during the rapid expansion process, which will lead to a complex two-phase flow inside the wind tunnel and even change the design flow conditions at the nozzle exit. The coupling of the phase transition and the compressible flow makes the estimation of the condensation effects in such wind tunnels very difficult and time-consuming. In this work, a reduced theoretical model is developed to approximately compute the nozzle-exit conditions of a flow including real-gas and homogeneous condensation effects. Specifically, the conservation equations of the axisymmetric flow are first approximated in the quasi-one-dimensional way. Then, the complex process is split into two steps, i.e., a real-gas nozzle flow but excluding condensation, resulting in supersaturated nozzle-exit conditions, and a discontinuous jump at the end of the nozzle from the supersaturated state to a saturated state. Compared with two-dimensional numerical simulations implemented with a detailed condensation model, the reduced model predicts the flow parameters with good accuracy except for some deviations caused by the two-dimensional effect. Therefore, this reduced theoretical model can provide a fast, simple but also accurate estimation of the condensation effect in combustion-heated hypersonic tunnels.

A time-compressed simulated geomagnetic storm influences the nest-exiting flight angles of the stingless bee Tetragonisca angustula

NASA Astrophysics Data System (ADS)

Esquivel, D. M. S.; Corrêa, A. A. C.; Vaillant, O. S.; de Melo, V. Bandeira; Gouvêa, G. S.; Ferreira, C. G.; Ferreira, T. A.; Wajnberg, E.

2014-03-01

Insects have been used as models for understanding animal orientation. It is well accepted that social insects such as honeybees and ants use different natural cues in their orientation mechanism. A magnetic sensitivity was suggested for the stingless bee Schwarziana quadripunctata, based on the observation of a surprising effect of a geomagnetic storm on the nest-exiting flight angles. Stimulated by this result, in this paper, the effects of a time-compressed simulated geomagnetic storm (TC-SGS) on the nest-exiting flight angles of another stingless bee, Tetragonisca angustula, are presented. Under an applied SGS, either on the horizontal or vertical component of the geomagnetic field, both nest-exiting flight angles, dip and azimuth, are statistically different from those under geomagnetic conditions. The angular dependence of ferromagnetic resonance (FMR) spectra of whole stingless bees shows the presence of organized magnetic nanoparticles in their bodies, which indicates this material as a possible magnetic detector.

A time-compressed simulated geomagnetic storm influences the nest-exiting flight angles of the stingless bee Tetragonisca angustula.

PubMed

Esquivel, D M S; Corrêa, A A C; Vaillant, O S; de Melo, V Bandeira; Gouvêa, G S; Ferreira, C G; Ferreira, T A; Wajnberg, E

2014-03-01

Insects have been used as models for understanding animal orientation. It is well accepted that social insects such as honeybees and ants use different natural cues in their orientation mechanism. A magnetic sensitivity was suggested for the stingless bee Schwarziana quadripunctata, based on the observation of a surprising effect of a geomagnetic storm on the nest-exiting flight angles. Stimulated by this result, in this paper, the effects of a time-compressed simulated geomagnetic storm (TC-SGS) on the nest-exiting flight angles of another stingless bee, Tetragonisca angustula, are presented. Under an applied SGS, either on the horizontal or vertical component of the geomagnetic field, both nest-exiting flight angles, dip and azimuth, are statistically different from those under geomagnetic conditions. The angular dependence of ferromagnetic resonance (FMR) spectra of whole stingless bees shows the presence of organized magnetic nanoparticles in their bodies, which indicates this material as a possible magnetic detector.

Evaluation of circularity error in drilling of syntactic foam composites

NASA Astrophysics Data System (ADS)

Ashrith H., S.; Doddamani, Mrityunjay; Gaitonde, Vinayak

2018-04-01

Syntactic foams are widely used in structural applications of automobiles, aircrafts and underwater vehicles due to their lightweight properties combined with high compression strength and low moisture absorption. Structural application requires drilling of holes for assembly purpose. In this investigation response surface methodology based mathematical models are used to analyze the effects of cutting speed, feed, drill diameter and filler content on circularity error both at entry and exit level in drilling of glass microballoon reinforced epoxy syntactic foam. Experiments are conducted based on full factorial design using solid coated tungsten carbide twist drills. The parametric analysis reveals that circularity error is highly influenced by drill diameter followed by spindle speed at the entry and exit level. Parametric analysis also reveals that increasing filler content decreases circularity error by 13.65 and 11.96% respectively at entry and exit levels. Average circularity error at the entry level is found to be 23.73% higher than at the exit level.

An Empirical Jet-Surface Interaction Noise Model with Temperature and Nozzle Aspect Ratio Effects

NASA Technical Reports Server (NTRS)

Brown, Cliff

2015-01-01

An empirical model for jet-surface interaction (JSI) noise produced by a round jet near a flat plate is described and the resulting model evaluated. The model covers unheated and hot jet conditions (1 less than or equal to jet total temperature ratio less than or equal to 2.7) in the subsonic range (0.5 less than or equal to M(sub a) less than or equal to 0.9), surface lengths 0.6 less than or equal to (axial distance from jet exit to surface trailing edge (inches)/nozzle exit diameter) less than or equal to 10, and surface standoff distances (0 less than or equal to (radial distance from jet lipline to surface (inches)/axial distance from jet exit to surface trailing edge (inches)) less than or equal to 1) using only second-order polynomials to provide predictable behavior. The JSI noise model is combined with an existing jet mixing noise model to produce exhaust noise predictions. Fit quality metrics and comparisons to between the predicted and experimental data indicate that the model is suitable for many system level studies. A first-order correction to the JSI source model that accounts for the effect of nozzle aspect ratio is also explored. This correction is based on changes to the potential core length and frequency scaling associated with rectangular nozzles up to 8:1 aspect ratio. However, more work is needed to refine these findings into a formal model.

Feedback controlled optics with wavefront compensation

NASA Technical Reports Server (NTRS)

Breckenridge, William G. (Inventor); Redding, David C. (Inventor)

1993-01-01

The sensitivity model of a complex optical system obtained by linear ray tracing is used to compute a control gain matrix by imposing the mathematical condition for minimizing the total wavefront error at the optical system's exit pupil. The most recent deformations or error states of the controlled segments or optical surfaces of the system are then assembled as an error vector, and the error vector is transformed by the control gain matrix to produce the exact control variables which will minimize the total wavefront error at the exit pupil of the optical system. These exact control variables are then applied to the actuators controlling the various optical surfaces in the system causing the immediate reduction in total wavefront error observed at the exit pupil of the optical system.

Experimental and raytrace results for throat-to-throat compound parabolic concentrators

NASA Technical Reports Server (NTRS)

Leviton, D. B.; Leitch, J. W.

1986-01-01

Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer). The design of one pair of cones is discussed, also an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

Association of rheumatic diseases with early exit from paid employment in Portugal.

PubMed

Laires, Pedro A; Gouveia, Miguel

2014-04-01

To examine the association between rheumatic diseases (RD) and other chronic morbidity with early exit from paid employment in the Portuguese population. The study population consisted of all people between 50 and 64 years of age (3,762 men and 4,241 women) who participated in the Portuguese National Health Survey, conducted in 2005/2006. Data were collected on demographics, ill-health, lifestyle, and socioeconomic factors. Logistic regression was used to estimate the isolated effect of rheumatic diseases and other chronic diseases on the likelihood of exit from paid employment. At the time of the survey, 45.1 % of the Portuguese population with ages between 50 and 64 years old were not employed. In the nonemployed population, 31.6 % self-reported "poor" to "very poor" health, whereas 16.4 % did so in the employed population. A larger average number of major chronic diseases per capita were also found in those not employed (1.9 vs. 1.4, p < 0.001). In the multivariate models, chronic diseases were associated with early exit from paid employment. In particular, rheumatic diseases were more prevalent (43.4 vs. 32.1 %) and associated with early exit from work (OR 1.31; CI 1.12-1.52, p = 0.001). This study suggests an association between RD and other major chronic diseases with early exit from paid employment in Portugal. Thus, health and social protection policies should target these chronic disorders in order to better address sustainability issues and social protection effectiveness.

46th Annual Gun and Missile Systems Conference and Exhibition. Volume 3 - Thursday

DTIC Science & Technology

2011-09-01

Grade Sensors Through Use of Accelerated Aging Principles Mr. Scott Gift 11657 Modeling of the Autofrettage Processes of a Gun Barrel Mr. Sudhir...Emissions Measured on the Outer Portion of a Composite Barrel Ms. Rushie Ghimire GUN & MISSILE SYSTEMS ADDITIONAL AUTHORS GUN & MISSILE SYSTEMS...Transportation – Loading – Gun Fire to Barrel Exit – After Barrel Exit • Passing: Fuze safety devices remain safe; safe for disposal or safe for

Why Do Some Employees Fall into and Fail to Exit a Job-Lock Situation?

PubMed Central

Groot, Wim; Pavlova, Milena

2013-01-01

Previous studies have paid little attention to the employees' ability to exit a job-lock situation and factors that determine this ability. It remains unclear why some employees who experience job lock are able to exit this state while others remain in job lock. We use longitudinal data to identify employees who have fallen in the state of job lock and their subsequent behavior—exiting or remaining in job lock. By use of a first-order Markov transition models, we analyze the relevance of sociodemographic features, employment, occupational, sectoral, and contextual factors, as well as personality characteristics in explaining the transition or its absence. Overall the results show that both demographic factors and work-related aspects increase the likelihood that an employee enters the long-term job lock state (especially for older, married, full-time employed, those in a craft occupation and governmental sector, and in a region with high unemployment). Mental health problems and personality characteristics (low peak-end self-esteem and decisional procrastination) have a significant effect on the probability to stay in long-term job lock. On the contrary, having a managerial, service, or associate occupation, working in the private sector, and having promotion opportunities increase the chance of an exit from the state of job lock. PMID:23737809

Exit probability of the one-dimensional q-voter model: Analytical results and simulations for large networks

NASA Astrophysics Data System (ADS)

Timpanaro, André M.; Prado, Carmen P. C.

2014-05-01

We discuss the exit probability of the one-dimensional q-voter model and present tools to obtain estimates about this probability, both through simulations in large networks (around 107 sites) and analytically in the limit where the network is infinitely large. We argue that the result E(ρ )=ρq/ρq+(1-ρ)q, that was found in three previous works [F. Slanina, K. Sznajd-Weron, and P. Przybyła, Europhys. Lett. 82, 18006 (2008), 10.1209/0295-5075/82/18006; R. Lambiotte and S. Redner, Europhys. Lett. 82, 18007 (2008), 10.1209/0295-5075/82/18007, for the case q =2; and P. Przybyła, K. Sznajd-Weron, and M. Tabiszewski, Phys. Rev. E 84, 031117 (2011), 10.1103/PhysRevE.84.031117, for q >2] using small networks (around 103 sites), is a good approximation, but there are noticeable deviations that appear even for small systems and that do not disappear when the system size is increased (with the notable exception of the case q =2). We also show that, under some simple and intuitive hypotheses, the exit probability must obey the inequality ρq/ρq+(1-ρ)≤E(ρ)≤ρ/ρ +(1-ρ)q in the infinite size limit. We believe this settles in the negative the suggestion made [S. Galam and A. C. R. Martins, Europhys. Lett. 95, 48005 (2001), 10.1209/0295-5075/95/48005] that this result would be a finite size effect, with the exit probability actually being a step function. We also show how the result that the exit probability cannot be a step function can be reconciled with the Galam unified frame, which was also a source of controversy.

Leaving the labour market: the impact of exit routes from employment to retirement on health and wellbeing in old age.

PubMed

Halleröd, Björn; Örestig, Johan; Stattin, Mikael

2013-03-01

The study analyses whether and to what degree specific routes into retirement affect older people, i.e. the relationship between heterogeneous exit patterns and post-retirement health and wellbeing. We used longitudinal data from two points in time; data related to t 0 were collected in 1993, 1994, 1995 and 1996 and data related to t 1 were collected in 2002 and 2003 ( N  = 589). We focused on older people (55+ at t 1 ) who were employed at t 0 and retired at t 1 . We used confirmative factor analysis to identify identical measures of health and wellbeing at both t 0 and t 1 . Hence, we were able to control for pre-retirement health and wellbeing when evaluating the effects of different exit routes. These routes were defined as dependence on incomes from sickness benefit, disability pension, part-time pension, unemployment insurance and active labour market programmes. Our initial structural equation model showed a clear relation between exit routes and post-retirement wellbeing. People who prior to retirement were pushed into social benefit programmes related to health and unemployment were significantly worse off as retirees, especially those with health-related benefits. However, these relationships disappeared once pre-retirement wellbeing was added to the model. Our main conclusion is that post-retirement wellbeing first and foremost is a consequence of accumulation of advantages and disadvantages during the life course. Both labour market exit routes and post-retirement wellbeing can be seen as outcomes of this process. There are no independent effects of the retirement process. Judging from our findings, there is no reason to believe that involvement in social security programmes allowing early retirement on health grounds has any additional negative consequences for health and wellbeing.

Radiation dose uncertainty and correction for a mouse orthotopic and xenograft irradiation model.

PubMed

Gan, Gregory N; Altunbas, Cem; Morton, John J; Eagles, Justin; Backus, Jennifer; Dzingle, Wayne; Raben, David; Jimeno, Antonio

2016-01-01

In animal irradiation models, reported dose can vary significantly from the actual doses delivered. We describe an effective method for in vivo dose verification. Mice bearing commercially-available cell line or patient-derived tumor cell orthotopic or flank xenografts were irradiated using a 160 kVp, 25 mA X-ray source. Entrance dose was evaluated using optically-stimulated luminescence dosimeters (OSLD) and exit dose was assessed using radiochromic film dosimetry. Tumor position within the irradiation field was validated using external fiducial markers. The average entrance dose in orthotopic tumors from 10 OSLDs placed on two different animal irradiation days was 514 ± 37 cGy (range: 437-545). Exit dose measurements taken from seven radiochromic films on two separate days were 341 ± 21 cGy (a 34% attenuation). Flank tumor irradiation doses measured by OSLD were 368 ± 9 cGy compared to exit doses of 330 cGy measured by radiochromic film. Variations related to the irradiation model can lead to significant under or overdosing in vivo which can affect tumor control and/or biologic endpoints that are dose-dependent. We recommend that dose measurements be determined empirically based on the mouse model and irradiator used and dose compensation adjustments performed to ensure correct and appropriate doses.

Identifying Novel Phenotypes of Vulnerability and Resistance to Activity-Based Anorexia in Adolescent Female Rats

PubMed Central

Barbarich-Marsteller, Nicole C.; Underwood, Mark D.; Foltin, Richard W.; Myers, Michael M.; Walsh, B. Timothy; Barrett, Jeffrey S.; Marsteller, Douglas A.

2018-01-01

Objective Activity-based anorexia is a translational rodent model that results in severe weight loss, hyperactivity, and voluntary self-starvation. The goal of our investigation was to identify vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats. Method Sprague-Dawley rats were maintained under conditions of restricted access to food (N = 64; or unlimited access, N = 16) until experimental exit, predefined as a target weight loss of 30–35% or meeting predefined criteria for animal health. Nonlinear mixed effects statistical modeling was used to describe wheel running behavior, time to event analysis was used to assess experimental exit, and a regressive partitioning algorithm was used to classify phenotypes. Results Objective criteria were identified for distinguishing novel phenotypes of activity-based anorexia, including a vulnerable phenotype that conferred maximal hyperactivity, minimal food intake, and the shortest time to experimental exit, and a resistant phenotype that conferred minimal activity and the longest time to experimental exit. Discussion The identification of objective criteria for defining vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats provides an important framework for studying the neural mechanisms that promote vulnerability to or protection against the development of self-starvation and hyperactivity during adolescence. Ultimately, future studies using these novel phenotypes may provide important translational insights into the mechanisms that promote these maladaptive behaviors characteristic of anorexia nervosa. PMID:23853140

Identifying novel phenotypes of vulnerability and resistance to activity-based anorexia in adolescent female rats.

PubMed

Barbarich-Marsteller, Nicole C; Underwood, Mark D; Foltin, Richard W; Myers, Michael M; Walsh, B Timothy; Barrett, Jeffrey S; Marsteller, Douglas A

2013-11-01

Activity-based anorexia is a translational rodent model that results in severe weight loss, hyperactivity, and voluntary self-starvation. The goal of our investigation was to identify vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats. Sprague-Dawley rats were maintained under conditions of restricted access to food (N = 64; or unlimited access, N = 16) until experimental exit, predefined as a target weight loss of 30-35% or meeting predefined criteria for animal health. Nonlinear mixed effects statistical modeling was used to describe wheel running behavior, time to event analysis was used to assess experimental exit, and a regressive partitioning algorithm was used to classify phenotypes. Objective criteria were identified for distinguishing novel phenotypes of activity-based anorexia, including a vulnerable phenotype that conferred maximal hyperactivity, minimal food intake, and the shortest time to experimental exit, and a resistant phenotype that conferred minimal activity and the longest time to experimental exit. The identification of objective criteria for defining vulnerable and resistant phenotypes of activity-based anorexia in adolescent female rats provides an important framework for studying the neural mechanisms that promote vulnerability to or protection against the development of self-starvation and hyperactivity during adolescence. Ultimately, future studies using these novel phenotypes may provide important translational insights into the mechanisms that promote these maladaptive behaviors characteristic of anorexia nervosa. Copyright © 2013 Wiley Periodicals, Inc.

Agent-Based Crowd Simulation Considering Emotion Contagion for Emergency Evacuation Problem

NASA Astrophysics Data System (ADS)

Faroqi, H.; Mesgari, M.-S.

2015-12-01

During emergencies, emotions greatly affect human behaviour. For more realistic multi-agent systems in simulations of emergency evacuations, it is important to incorporate emotions and their effects on the agents. In few words, emotional contagion is a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes. In this study, we simulate an emergency situation in an open square area with three exits considering Adults and Children agents with different behavior. Also, Security agents are considered in order to guide Adults and Children for finding the exits and be calm. Six levels of emotion levels are considered for each agent in different scenarios and situations. The agent-based simulated model initialize with the random scattering of agent populations and then when an alarm occurs, each agent react to the situation based on its and neighbors current circumstances. The main goal of each agent is firstly to find the exit, and then help other agents to find their ways. Numbers of exited agents along with their emotion levels and damaged agents are compared in different scenarios with different initialization in order to evaluate the achieved results of the simulated model. NetLogo 5.2 is used as the multi-agent simulation framework with R language as the developing language.

Convair XF-102 Model in the 8- by 6-Foot Supersonic Wind Tunnel

NASA Image and Video Library

1953-08-21

A .10-scale model of Convair’s XF-102 in the 8- by 6-Foot Supersonic Wind Tunnel at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory for jet exit studies. The XF-102 was a prototype of the F-102 Delta Dagger. The F-102 served as an interceptor against long range bombers from the Soviet Union. The aircraft was powered by a Pratt and Whitney J57 turbojet. The first prototype crashed two weeks after is first flight on October 24, 1953, just months after this photograph. Engineers then incorporated the fixed-wing design to reduce drag at supersonic speeds. The production model F-102 became the first delta-wing supersonic aircraft in operation. The 8- by 6-Foot Supersonic Wind Tunnel is used to study propulsion systems, including inlets and exit nozzles, combustion fuel injectors, flame holders, exit nozzles, and controls on ramjet and turbojet engines. Flexible sidewalls alter the tunnel’s nozzle shape to vary the Mach number during operation. A seven-stage axial compressor, driven by three electric motors that yield a total of 87,000 horsepower, generates air speeds from Mach 0.36 to 2.0.

The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO 2 Working Fluid

DOE PAGES

Liese, Eric; Zitney, Stephen E.

2017-06-26

A multi-stage centrifugal compressor model is presented with emphasis on analyzing use of an exit flow coefficient vs. an inlet flow coefficient performance parameter to predict off-design conditions in the critical region of a supercritical carbon dioxide (CO 2) power cycle. A description of the performance parameters is given along with their implementation in a design model (number of stages, basic sizing, etc.) and a dynamic model (for use in transient studies). A design case is shown for two compressors, a bypass compressor and a main compressor, as defined in a process simulation of a 10 megawatt (MW) supercritical COmore » 2 recompression Brayton cycle. Simulation results are presented for a simple open cycle and closed cycle process with changes to the inlet temperature of the main compressor which operates near the CO 2 critical point. Results showed some difference in results using the exit vs. inlet flow coefficient correction, however, it was not significant for the range of conditions examined. Here, this paper also serves as a reference for future works, including a full process simulation of the 10 MW recompression Brayton cycle.« less

Turbofan forced mixer lobe flow modeling. 1: Experimental and analytical assessment

NASA Technical Reports Server (NTRS)

Barber, T.; Paterson, R. W.; Skebe, S. A.

1988-01-01

A joint analytical and experimental investigation of three-dimensional flowfield development within the lobe region of turbofan forced mixer nozzles is described. The objective was to develop a method for predicting the lobe exit flowfield. In the analytical approach, a linearized inviscid aerodynamical theory was used for representing the axial and secondary flows within the three-dimensional convoluted mixer lobes and three-dimensional boundary layer analysis was applied thereafter to account for viscous effects. The experimental phase of the program employed three planar mixer lobe models having different waveform shapes and lobe heights for which detailed measurements were made of the three-dimensional velocity field and total pressure field at the lobe exit plane. Velocity data was obtained using Laser Doppler Velocimetry (LDV) and total pressure probing and hot wire anemometry were employed to define exit plane total pressure and boundary layer development. Comparison of data and analysis was performed to assess analytical model prediction accuracy. As a result of this study a planar mixed geometry analysis was developed. A principal conclusion is that the global mixer lobe flowfield is inviscid and can be predicted from an inviscid analysis and Kutta condition.

Spatial Correlation in the Ambient Core Noise Field of a Turbofan Engine

NASA Technical Reports Server (NTRS)

Miles, Jeffrey Hilton

2012-01-01

An acoustic transfer function relating combustion noise and turbine exit noise in the presence of enclosed ambient core noise is investigated using a dynamic system model and an acoustic system model for the particular turbofan engine studied and for a range of operating conditions. Measurements of cross-spectra magnitude and phase between the combustor and turbine exit and auto-spectra at the turbine exit and combustor are used to show the presence of indirect and direct combustion noise over the frequency range of 0 400 Hz. The procedure used evaluates the ratio of direct to indirect combustion noise. The procedure used also evaluates the post-combustion residence time in the combustor which is a factor in the formation of thermal NOx and soot in this region. These measurements are masked by the ambient core noise sound field in this frequency range which is observable since the transducers are situated within an acoustic wavelength of one another. An ambient core noise field model based on one and two dimensional spatial correlation functions is used to replicate the spatially correlated response of the pair of transducers. The spatial correlation function increases measured attenuation due to destructive interference and masks the true attenuation of the turbine.

Releasing the cohesin ring: A rigid scaffold model for opening the DNA exit gate by Pds5 and Wapl.

PubMed

Ouyang, Zhuqing; Yu, Hongtao

2017-04-01

The ring-shaped ATPase machine, cohesin, regulates sister chromatid cohesion, transcription, and DNA repair by topologically entrapping DNA. Here, we propose a rigid scaffold model to explain how the cohesin regulators Pds5 and Wapl release cohesin from chromosomes. Recent studies have established the Smc3-Scc1 interface as the DNA exit gate of cohesin, revealed a requirement for ATP hydrolysis in ring opening, suggested regulation of the cohesin ATPase activity by DNA and Smc3 acetylation, and provided insights into how Pds5 and Wapl open this exit gate. We hypothesize that Pds5, Wapl, and SA1/2 form a rigid scaffold that docks on Scc1 and anchors the N-terminal domain of Scc1 (Scc1N) to the Smc1 ATPase head. Relative movements between the Smc1-3 ATPase heads driven by ATP and Wapl disrupt the Smc3-Scc1 interface. Pds5 binds the dissociated Scc1N and prolongs this open state of cohesin, releasing DNA. We review the evidence supporting this model and suggest experiments that can further test its key principles. © 2017 WILEY Periodicals, Inc.

Effect of velocity and temperature distribution at the hole exit on film cooling of turbine blades

NASA Technical Reports Server (NTRS)

Garg, Vijay K.; Gaugler, Raymond E.

1995-01-01

An existing three-dimensional Navier-Stokes code, modified to include film cooling considerations, has been used to study the effect of coolant velocity and temperature distribution at the hole exit on the heat transfer coefficient on three-film-cooled turbine blades, namely, the C3X vane, the VKI rotor, and the ACE rotor. Results are also compared with the experimental data for all the blades. Moreover, Mayle's transition criterion, Forest's model for augmentation of leading edge heat transfer due to freestream turbulence, and Crawford's model for augmentation of eddy viscosity due to film cooling are used. Use of Mayle's and Forest's models is relevant only for the ACE rotor due to the absence of showerhead cooling on this rotor. It is found that, in some cases, the effect of distribution of coolant velocity and temperature at the hole exit can be as much as 60% on the heat transfer coefficient at the blade suction surface, and 50% at the pressure surface. Also, different effects are observed on the pressure and suction surface depending upon the blade as well as upon the hole shape, conical or cylindrical.

The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO 2 Working Fluid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liese, Eric; Zitney, Stephen E.

A multi-stage centrifugal compressor model is presented with emphasis on analyzing use of an exit flow coefficient vs. an inlet flow coefficient performance parameter to predict off-design conditions in the critical region of a supercritical carbon dioxide (CO 2) power cycle. A description of the performance parameters is given along with their implementation in a design model (number of stages, basic sizing, etc.) and a dynamic model (for use in transient studies). A design case is shown for two compressors, a bypass compressor and a main compressor, as defined in a process simulation of a 10 megawatt (MW) supercritical COmore » 2 recompression Brayton cycle. Simulation results are presented for a simple open cycle and closed cycle process with changes to the inlet temperature of the main compressor which operates near the CO 2 critical point. Results showed some difference in results using the exit vs. inlet flow coefficient correction, however, it was not significant for the range of conditions examined. Here, this paper also serves as a reference for future works, including a full process simulation of the 10 MW recompression Brayton cycle.« less

Learning outcomes as a tool to assess progression.

PubMed

Harden, Ronald M

2007-09-01

In the move to outcome-based education (OBE) much of the attention has focussed on the exit learning outcomes-the outcomes expected of a student at the end of a course of studies. It is important also to plan for and monitor students progression to the exit outcomes. A model is described for considering this progression through the phases of undergraduate education. Four dimensions are included-increasing breadth, increasing depth, increasing utility and increasing proficiency. The model can also be used to develop a blueprint for a more seamless link between undergraduate education, postgraduate training and continuing professional development. The progression model recognises the complexities of medical practice and medical education. It supports the move to student-centred and adaptive approaches to learning in an OBE environment.

A linear shock cell model for non-circular jets using conformal mapping with a pseudo-spectral hybrid scheme

NASA Technical Reports Server (NTRS)

Bhat, Thonse R. S.; Baty, Roy S.; Morris, Philip J.

1990-01-01

The shock structure in non-circular supersonic jets is predicted using a linear model. This model includes the effects of the finite thickness of the mixing layer and the turbulence in the jet shear layer. A numerical solution is obtained using a conformal mapping grid generation scheme with a hybrid pseudo-spectral discretization method. The uniform pressure perturbation at the jet exit is approximated by a Fourier-Mathieu series. The pressure at downstream locations is obtained from an eigenfunction expansion that is matched to the pressure perturbation at the jet exit. Results are presented for a circular jet and for an elliptic jet of aspect ratio 2.0. Comparisons are made with experimental data.

Wisconsin's BadgerCare Plus reform: impact on low-income families' enrollment and retention in public coverage.

PubMed

Leininger, Lindsey Jeanne; Friedsam, Donna; Dague, Laura; Mok, Shannon; Hynes, Emma; Bergum, Alison; Aksamitauskas, Milda; Oliver, Thomas; DeLeire, Thomas

2011-02-01

To examine the impact of a Wisconsin health care reform enacted in early 2008 on public insurance enrollment and retention. Administrative data covering the period January 2007 to November 2009. We calculate unadjusted enrollment trends and exit rates stratified by age, income group, and enrollment mode. Kaplan-Meier curves and Cox proportional hazards models are estimated to assess the impact of the reform on program exits. Overall enrollment increased by approximately one-third and exit rates decreased by approximately one-fifth. The majority of new enrollment came from the previously income eligible. Wisconsin's enactment of eligibility expansions coupled with administrative simplification and targeted marketing and outreach efforts were successful in enrolling and retaining low-income children and families in public coverage. © Health Research and Educational Trust.

The exit-time problem for a Markov jump process

NASA Astrophysics Data System (ADS)

Burch, N.; D'Elia, M.; Lehoucq, R. B.

2014-12-01

The purpose of this paper is to consider the exit-time problem for a finite-range Markov jump process, i.e, the distance the particle can jump is bounded independent of its location. Such jump diffusions are expedient models for anomalous transport exhibiting super-diffusion or nonstandard normal diffusion. We refer to the associated deterministic equation as a volume-constrained nonlocal diffusion equation. The volume constraint is the nonlocal analogue of a boundary condition necessary to demonstrate that the nonlocal diffusion equation is well-posed and is consistent with the jump process. A critical aspect of the analysis is a variational formulation and a recently developed nonlocal vector calculus. This calculus allows us to pose nonlocal backward and forward Kolmogorov equations, the former equation granting the various moments of the exit-time distribution.

A Reduced Ejector Equation,

DTIC Science & Technology

Ejectors , * Thrust augmentation , * Thrust augmentor nozzles, *Mathematical models, Equations, Supersonic characteristics, Inlets, Exits, Aerodynamics, Vertical takeoff aircraft, Short takeoff aircraft, Workshops

Comparison of options for reduction of noise in the test section of the NASA Langley 4x7m wind tunnel, including reduction of nozzle area

NASA Technical Reports Server (NTRS)

Hayden, R. E.

1984-01-01

The acoustically significant features of the NASA 4X7m wind tunnel and the Dutch-German DNW low speed tunnel are compared to illustrate the reasons for large differences in background noise in the open jet test sections of the two tunnels. Also introduced is the concept of reducing test section noise levels through fan and turning vane source reductions which can be brought about by reducing the nozzle cross sectional area, and thus the circuit mass flow for a particular exit velocity. The costs and benefits of treating sources, paths, and changing nozzle geometry are reviewed.

Distinctive properties of metastasis-initiating cells

PubMed Central

Celià-Terrassa, Toni; Kang, Yibin

2016-01-01

Primary tumors are known to constantly shed a large number of cancer cells into systemic dissemination, yet only a tiny fraction of these cells is capable of forming overt metastases. The tremendous rate of attrition during the process of metastasis implicates the existence of a rare and unique population of metastasis-initiating cells (MICs). MICs possess advantageous traits that may originate in the primary tumor but continue to evolve during dissemination and colonization, including cellular plasticity, metabolic reprogramming, the ability to enter and exit dormancy, resistance to apoptosis, immune evasion, and co-option of other tumor and stromal cells. Better understanding of the molecular and cellular hallmarks of MICs will facilitate the development and deployment of novel therapeutic strategies. PMID:27083997

AN/SLQ-32 EW System Model: and Expandable, Object-Oriented, Process- Based Simulation

DTIC Science & Technology

1992-09-01

CONST threshold = 0.1; timetol = 0.01; orientol = 5.8; VAR rec, recLast :BufferBeamRecType; time,power : REAL; powerl,orientation : REAL; BEGIN NEW...PulseGroup); rec:-ASK BufferBeam Removed; time: =rec. time; orientation: =rec. orientation; OUTPUT ( "ORIENREFI, orientation); recLast :=ASK BufferBeam Last...TO Add(rec); IF (rec= recLast ) EXIT; END IF; rec :=ASK BufferBeam Remove o; ELSE ASK BufferBeam TO Add(rec); IF (rec = recLast ) EXIT; END IF; rec

Flow Distribution Control Characteristics in Marine Gas Turbine Waste-Heat Recovery Systems. Phase I. Flow Distribution Characteristics and Control in Diffusers.

DTIC Science & Technology

1981-08-01

provide the lowest rate of momentum outflow and thus yield maximum diffuser efficiency. In their study, Wolf and Johnston (Ref. 1.12) used screens made...other words, the uniform velocity at the diffuser exit implies the lowest exit velocity attainable for a given flow rate and lowest rate of momentum ... momentum , and energy and the equation of state. The procedures of manipulating these partial differential iations into an analytical model for analyzing

AALC Fan Model Test Program

DTIC Science & Technology

1979-05-08

Prediction. Scaling. Fan Design. 29AOSY14ACY (Cettm.. a P#`04 rv1s. *It UO004N 01- dew 16001 bYstI 610 01c Nh A 12-inch-diameter centrifugal fan impeller...Performance, 3500 RPM84............ 53 Inlet Bellmouth Velocity Survey , Oper Point A, Config 3. 54 Inlet Bellmouth Velocity Survey, Oper Point B...Config 3. 8& 55 Inlet Bellmouth Velocity Survey, Oper Point C, Config 3. ss So Volute Exit Plane Press. Measurement Locations, Config 3 89 57 Volute Exit

Experimental Assessment of the Emissions Control Potential of a Rich/Quench/Lean Combustor for High Speed Civil Transport Aircraft Engines

NASA Technical Reports Server (NTRS)

Rosfjord, T. J.; Padget, F. C.; Tacina, Robert R. (Technical Monitor)

2001-01-01

In support of Pratt & Whitney efforts to define the Rich burn/Quick mix/Lean burn (RQL) combustor for the High Speed Civil Transport (HSCT) aircraft engine, UTRC conducted a flametube-scale study of the RQL concept. Extensive combustor testing was performed at the Supersonic Cruise (SSC) condition of a HSCT engine cycle, Data obtained from probe traverses near the exit of the mixing section confirmed that the mixing section was the critical component in controlling combustor emissions. Circular-hole configurations, which produced rapidly-, highly-penetrating jets, were most effective in limiting NOx. The spatial profiles of NOx and CO at the mixer exit were not directly interpretable using a simple flow model based on jet penetration, and a greater understanding of the flow and chemical processes in this section are required to optimize it. Neither the rich-combustor equivalence ratio nor its residence time was a direct contributor to the exit NOx. Based on this study, it was also concluded that (1) While NOx formation in both the mixing section and the lean combustor contribute to the overall emission, the NOx formation in the mixing section dominates. The gas composition exiting the rich combustor can be reasonably represented by the equilibrium composition corresponding to the rich combustor operating condition. Negligible NOx exits the rich combustor. (2) At the SSC condition, the oxidation processes occurring in the mixing section consume 99 percent of the CO exiting the rich combustor. Soot formed in the rich combustor is also highly oxidized, with combustor exit SAE Smoke Number <3. (3) Mixing section configurations which demonstrated enhanced emissions control at SSC also performed better at part-power conditions. Data from mixer exit traverses reflected the expected mixing behavior for off-design jet to crossflow momentum-flux ratios. (4) Low power operating conditions require that the RQL combustor operate as a lean-lean combustor to achieve low CO and high efficiency. (5) A RQL combustor can achieve the emissions goal of EINOX = 5 at the Supersonic Cruise operating condition for a HSCT engine.

Experimental Assessment of the Emissions Control Potential of a Rich/Quench/ Lean Combustor for High Speed Civil Transport Aircraft Engines

NASA Technical Reports Server (NTRS)

Tacina, Robert R. (Technical Monitor); Rosfjord, T. J.; Padget, F. C.

2001-01-01

In support of Pratt & Whitney efforts to define the Rich burn/Quick mix/Lean burn (RQL) combustor for the High Speed Civil Transport (HSCT) aircraft engine, UTRC conducted a flametube-scale study of the RQL concept. Extensive combustor testing was performed at the Supersonic Cruise (SSC) condition of an HSCT engine cycle. Data obtained from probe traverses near the exit of the mixing section confirmed that the mixing section was the critical component in controlling combustor emissions. Circular-hole configurations, which produced rapidly-, highly-penetrating jets, were most effective in limiting NO(x). The spatial profiles of NO(x) and CO at the mixer exit were not directly interpretable using a simple flow model based on jet penetration, and a greater understanding of the flow and chemical processes in this section are required to optimize it. Neither the rich-combustor equivalence ratio nor its residence time was a direct contributor to the exit NO(x). Based on this study, it was also concluded that: (1) While NO(x) formation in both the mixing section and the lean combustor contribute to the overall emission, the NOx formation in the mixing section dominates. The gas composition exiting the rich combustor can be reasonably represented by the equilibrium composition corresponding to the rich combustor operating condition. Negligible NO(x) exits the rich combustor. (2) At the SSC condition, the oxidation processes occurring in the mixing section consume 99 percent of the CO exiting the rich combustor. Soot formed in the rich combustor is also highly oxidized, with combustor exit SAE Smoke Number <3. (3) Mixing section configurations which demonstrated enhanced emissions control at SSC also performed better at part-power conditions. Data from mixer exit traverses reflected the expected mixing behavior for off-design jet to crossflow momentum-flux ratios. (4) Low power operating conditions require that the RQL combustor operate as a lean-lean combustor to achieve low CO and high efficiency. (5) An RQL combustor can achieve the emissions goal of EINO(x) = 5 at the Supersonic Cruise operating condition for an HSCT engine.

Modeling an Iodine Hall Thruster Plume in the Iodine Satellite (ISAT)

NASA Technical Reports Server (NTRS)

Choi, Maria

2016-01-01

An iodine-operated 200-W Hall thruster plume has been simulated using a hybrid-PIC model to predict the spacecraft surface-plume interaction for spacecraft integration purposes. For validation of the model, the plasma potential, electron temperature, ion current flux, and ion number density of xenon propellant were compared with available measurement data at the nominal operating condition. To simulate iodine plasma, various collision cross sections were found and used in the model. While time-varying atomic iodine species (i.e., I, I+, I2+) information is provided by HP Hall simulation at the discharge channel exit, the molecular iodine species (i.e., I2, I2+) are introduced as Maxwellian particles at the channel exit. Simulation results show that xenon and iodine plasma plumes appear to be very similar under the assumptions of the model. Assuming a sticking coefficient of unity, iodine deposition rate is estimated.

Modeling an Iodine Hall Thruster Plume in the Iodine Satellite (ISAT)

NASA Technical Reports Server (NTRS)

Choi, Maria

2016-01-01

An iodine-operated 200-W Hall thruster plume has been simulated using a hybrid-PIC model to predict the spacecraft surface-plume interaction for spacecraft integration purposes. For validation of the model, the plasma potential, electron temperature, ion current flux, and ion number density of xenon propellant were compared with available measurement data at the nominal operating condition. To simulate iodine plasma, various collision cross sections were found and used in the model. While time-varying atomic iodine species (i.e., I, I+, I2+) information is provided by HPHall simulation at the discharge channel exit, the molecular iodine species (i.e., I2, I2+) are introduced as Maxwellian particles at the channel exit. Simulation results show that xenon and iodine plasma plumes appear to be very similar under the assumptions of the model. Assuming a sticking coefficient of unity, iodine deposition rate is estimated.

Sauter mean diameter statistics of the starch dispersion atomized with hydraulic nozzle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Naz, Muhammad Yasin, E-mail: yasin603@yahoo.com; Ariwahjoedi, Bambang, E-mail: bambang-ariwahjoedi@petronas.com.my; Sulaiman, Shaharin Anwar, E-mail: shaharin@petronas.com.my

In the reported research work, the microscopic droplet velocity at different axial and radial locations downstream to the nozzle exit was studied by using a non-intrusive Laser Doppler Anemometry (LDA) techniques. These velocity measurements made in the viscous fluid spray sterams were used to predict the different breakup regimes in the flow. It was noticed that the droplet velocity decreased sharply downstream to the nozzle exit, whereas steady decrease in velocity was seen along the radial directions. For shorter injection time periods, the velocity downstream to the nozzle was not following the general breakup model. However, along the radial directionmore » it exactly followed the discussed model. Along the spray centerline, the velocity was decreasing sharply even at far points from the nozzle exit. It was difficult to identify the core region, transition region and fully developed spray region in the flow. It revealed that the jet breakup was not completed yet and further disintegration was taking place along the spray centerline for shorter injection periods below 250 ms.« less

Species and temperature measurement in H2/O2 rocket flow fields by means of Raman scattering diagnostics

NASA Technical Reports Server (NTRS)

De Groot, Wim A.; Weiss, Jonathan M.

1992-01-01

Validation of CFD codes developed for prediction and evaluation of rocket performance is hampered by a lack of experimental data. Nonintrusive laser based diagnostics are needed to provide spatially and temporally resolved gas dynamic and fluid dynamic measurements. This paper reports the first nonintrusive temperature and species measurements in the plume of a 110 N gaseous hydrogen/oxygen thruster at and below ambient pressures, obtained with spontaneous Raman spectroscopy. Measurements at 10 mm downstream of the exit plane are compared with predictions from a numerical solution of the axisymmetric Navier-Stokes and species transport equations with chemical kinetics, which fully model the combustor-nozzle-plume flowfield. The experimentally determined oxygen number density at the centerline at 10 mm downstream of the exit plane is four times that predicted by the model. The experimental number density data fall between those numerically predicted for the exit and 10 mm downstream planes in both magnitude and radial gradient. The predicted temperature levels are within 10 to 15 percent of measured values.

Enrichment Zoning Options for the Small Nuclear Rocket Engine (SNRE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruce G. Schnitzler; Stanley K. Borowski

2010-07-01

Advancement of U.S. scientific, security, and economic interests through a robust space exploration program requires high performance propulsion systems to support a variety of robotic and crewed missions beyond low Earth orbit. In NASA’s recent Mars Design Reference Architecture (DRA) 5.0 study (NASA-SP-2009-566, July 2009), nuclear thermal propulsion (NTP) was again selected over chemical propulsion as the preferred in-space transportation system option because of its high thrust and high specific impulse (-900 s) capability, increased tolerance to payload mass growth and architecture changes, and lower total initial mass in low Earth orbit. An extensive nuclear thermal rocket technology development effortmore » was conducted from 1955-1973 under the Rover/NERVA Program. The Small Nuclear Rocket Engine (SNRE) was the last engine design studied by the Los Alamos National Laboratory during the program. At the time, this engine was a state-of-the-art design incorporating lessons learned from the very successful technology development program. Past activities at the NASA Glenn Research Center have included development of highly detailed MCNP Monte Carlo transport models of the SNRE and other small engine designs. Preliminary core configurations typically employ fuel elements with fixed fuel composition and fissile material enrichment. Uniform fuel loadings result in undesirable radial power and temperature profiles in the engines. Engine performance can be improved by some combination of propellant flow control at the fuel element level and by varying the fuel composition. Enrichment zoning at the fuel element level with lower enrichments in the higher power elements at the core center and on the core periphery is particularly effective. Power flattening by enrichment zoning typically results in more uniform propellant exit temperatures and improved engine performance. For the SNRE, element enrichment zoning provided very flat radial power profiles with 551 of the 564 fuel elements within 1% of the average element power. Results for this and alternate enrichment zoning options for the SNRE are compared.« less

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people.

PubMed

Shinmoto Torres, Roberto L; Visvanathan, Renuka; Abbott, Derek; Hill, Keith D; Ranasinghe, Damith C

2017-01-01

Falls in hospitals are common, therefore strategies to minimize the impact of these events in older patients and needs to be examined. In this pilot study, we investigate a movement monitoring sensor system for identifying bed and chair exits using a wireless wearable sensor worn by hospitalized older patients. We developed a movement monitoring sensor system that recognizes bed and chair exits. The system consists of a machine learning based activity classifier and a bed and chair exit recognition process based on an activity score function. Twenty-six patients, aged 71 to 93 years old, hospitalized in the Geriatric Evaluation and Management Unit participated in the supervised trials. They wore over their attire a battery-less, lightweight and wireless sensor and performed scripted activities such as getting off the bed and chair. We investigated the system performance in recognizing bed and chair exits in hospital rooms where RFID antennas and readers were in place. The system's acceptability was measured using two surveys with 0-10 likert scales. The first survey measured the change in user perception of the system before and after a trial; the second survey, conducted only at the end of each trial, measured user acceptance of the system based on a multifactor sensor acceptance model. The performance of the system indicated an overall recall of 81.4%, precision of 66.8% and F-score of 72.4% for joint bed and chair exit recognition. Patients demonstrated improved perception of the system after use with overall score change from 7.8 to 9.0 and high acceptance of the system with score ≥ 6.7 for all acceptance factors. The present pilot study suggests the use of wireless wearable sensors is feasible for detecting bed and chair exits in a hospital environment.

A battery-less and wireless wearable sensor system for identifying bed and chair exits in a pilot trial in hospitalized older people

PubMed Central

Visvanathan, Renuka; Abbott, Derek; Hill, Keith D.; Ranasinghe, Damith C.

2017-01-01

Falls in hospitals are common, therefore strategies to minimize the impact of these events in older patients and needs to be examined. In this pilot study, we investigate a movement monitoring sensor system for identifying bed and chair exits using a wireless wearable sensor worn by hospitalized older patients. We developed a movement monitoring sensor system that recognizes bed and chair exits. The system consists of a machine learning based activity classifier and a bed and chair exit recognition process based on an activity score function. Twenty-six patients, aged 71 to 93 years old, hospitalized in the Geriatric Evaluation and Management Unit participated in the supervised trials. They wore over their attire a battery-less, lightweight and wireless sensor and performed scripted activities such as getting off the bed and chair. We investigated the system performance in recognizing bed and chair exits in hospital rooms where RFID antennas and readers were in place. The system’s acceptability was measured using two surveys with 0–10 likert scales. The first survey measured the change in user perception of the system before and after a trial; the second survey, conducted only at the end of each trial, measured user acceptance of the system based on a multifactor sensor acceptance model. The performance of the system indicated an overall recall of 81.4%, precision of 66.8% and F-score of 72.4% for joint bed and chair exit recognition. Patients demonstrated improved perception of the system after use with overall score change from 7.8 to 9.0 and high acceptance of the system with score ≥ 6.7 for all acceptance factors. The present pilot study suggests the use of wireless wearable sensors is feasible for detecting bed and chair exits in a hospital environment. PMID:29016696

Effects of Fuel Cell Anode Recycle on Catalytic Fuel Reforming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shekhawat, Dushyant; Berry, D.A.; Gardner, T.H.

2007-06-01

The presence of steam in the reactant gas of a catalytic fuel reformer decreases the formation of carbon, minimizing catalyst deactivation. However, the operation of the reformer without supplemental water reduces the size, weight, cost, and overall complexity of the system. The work presented here examines experimentally two options for adding steam to the reformer inlet: (I) recycle of a simulated fuel cell anode exit gas (comprised of mainly CO2, H2O, and N2 and some H2 and CO) and (II) recycle of the reformate from the reformer exit back to the reformer inlet (mainly comprised of H2, CO, and N2more » and some H2O and CO2). As expected, anode gas recycle reduced the carbon formation and increased the hydrogen concentration in the reformate. However, reformer recycle was not as effective due principally to the lower water content in the reformate compared to the anode gas. In fact, reformate recycle showed slightly increased carbon formation compared to no recycle. In an attempt to understand the effects of individual gases in these recycle streams (H2, CO, CO2, N2, and H2O), individual gas species were independently introduced to the reformer feed.« less

Effects of fuel cell anode recycle on catalytic fuel reforming

DOE Office of Scientific and Technical Information (OSTI.GOV)

shekhawat, D.; Berry, D.; Gardner, T.

2007-01-01

The presence of steam in the reactant gas of a catalytic fuel reformer decreases the formation of carbon, minimizing catalyst deactivation. However, the operation of the reformer without supplemental water reduces the size, weight, cost, and overall complexity of the system. The work presented here examines experimentally two options for adding steam to the reformer inlet: (I) recycle of a simulated fuel cell anode exit gas (comprised of mainly CO2, H2O, and N2 and some H2 and CO) and (II) recycle of the reformate from the reformer exit back to the reformer inlet (mainly comprised of H2, CO, and N2more » and some H2O and CO2). As expected, anode gas recycle reduced the carbon formation and increased the hydrogen concentration in the reformate. However, reformer recycle was not as effective due principally to the lower water content in the reformate compared to the anode gas. In fact, reformate recycle showed slightly increased carbon formation compared to no recycle. In an attempt to understand the effects of individual gases in these recycle streams (H2, CO, CO2, N2, and H2O), individual gas species were independently introduced to the reformer feed. Published by Elsevier B.V.« less

First-passage time of Brownian motion with dry friction.

PubMed

Chen, Yaming; Just, Wolfram

2014-02-01

We provide an analytic solution to the first-passage time (FPT) problem of a piecewise-smooth stochastic model, namely Brownian motion with dry friction, using two different but closely related approaches which are based on eigenfunction decompositions on the one hand and on the backward Kolmogorov equation on the other. For the simple case containing only dry friction, a phase-transition phenomenon in the spectrum is found which relates to the position of the exit point, and which affects the tail of the FPT distribution. For the model containing as well a driving force and viscous friction the impact of the corresponding stick-slip transition and of the transition to ballistic exit is evaluated quantitatively. The proposed model is one of the very few cases where FPT properties are accessible by analytical means.

A computer simulation of aircraft evacuation with fire

NASA Technical Reports Server (NTRS)

Middleton, V. E.

1983-01-01

A computer simulation was developed to assess passenger survival during the post-crash evacuation of a transport category aircraft when fire is a major threat. The computer code, FIREVAC, computes individual passenger exit paths and times to exit, taking into account delays and congestion caused by the interaction among the passengers and changing cabin conditions. Simple models for the physiological effects of the toxic cabin atmosphere are included with provision for including more sophisticated models as they become available. Both wide-body and standard-body aircraft may be simulated. Passenger characteristics are assigned stochastically from experimentally derived distributions. Results of simulations of evacuation trials and hypothetical evacuations under fire conditions are presented.

Computer program for design analysis of radial-inflow turbines

NASA Technical Reports Server (NTRS)

Glassman, A. J.

1976-01-01

A computer program written in FORTRAN that may be used for the design analysis of radial-inflow turbines was documented. The following information is included: loss model (estimation of losses), the analysis equations, a description of the input and output data, the FORTRAN program listing and list of variables, and sample cases. The input design requirements include the power, mass flow rate, inlet temperature and pressure, and rotational speed. The program output data includes various diameters, efficiencies, temperatures, pressures, velocities, and flow angles for the appropriate calculation stations. The design variables include the stator-exit angle, rotor radius ratios, and rotor-exit tangential velocity distribution. The losses are determined by an internal loss model.

Description and calibration of the Langley Hypersonic CF4 tunnel: A facility for simulating low gamma flow as occurs for a real gas

NASA Technical Reports Server (NTRS)

Midden, Raymond E.; Miller, Charles G., III

1985-01-01

The Langley Hypersonic CF4 Tunnel is a Mach 6 facility which simulates an important aspect of dissociative real-gas phenomena associated with the reentry of blunt vehicles, i.e., the decrease in the ratio of specific heats (gamma) that occurs within the shock layer of the vehicle. A general description of this facility is presented along with a discussion of the basic components, instrumentation, and operating procedure. Pitot-pressure surveys were made at the nozzle exit and downstream of the exit for reservoir temperatures from 1020 to 1495 R and reservoir pressures from 1000 to 2550 psia. A uniform test core having a diameter of circa 11 in. (0.55 times the nozzle-exit diameter) exists at the maximum value of reservoir pressure and temperature. The corresponding free-stream Mach number is 5.9, the unit Reynolds number is 4 x 10 to the 5th power per foot, the ratio of specific heats immediately behind a normal shock is 1.10, and the normal-shock density ratio is 12.6. When the facility is operated at reservoir temperatures below 1440 R, irregularities occur in the pitot-pressure profile within a small region about the nozzle centerline. These variations in pitot pressure indicate the existence of flow distrubances originating in the upstream region of the nozzle. This necessitates testing models off centerline in the uniform flow between the centerline region and either the nozzle boundary layer or the lip shock originating at the nozzle exit. Samples of data obtained in this facility with various models are presented to illustrate the effect of gamma on flow conditions about the model and the importance of knowing the magnitude of this effect.

Stop! border ahead: Automatic detection of subthalamic exit during deep brain stimulation surgery.

PubMed

Valsky, Dan; Marmor-Levin, Odeya; Deffains, Marc; Eitan, Renana; Blackwell, Kim T; Bergman, Hagai; Israel, Zvi

2017-01-01

Microelectrode recordings along preplanned trajectories are often used for accurate definition of the subthalamic nucleus (STN) borders during deep brain stimulation (DBS) surgery for Parkinson's disease. Usually, the demarcation of the STN borders is performed manually by a neurophysiologist. The exact detection of the borders is difficult, especially detecting the transition between the STN and the substantia nigra pars reticulata. Consequently, demarcation may be inaccurate, leading to suboptimal location of the DBS lead and inadequate clinical outcomes. We present machine-learning classification procedures that use microelectrode recording power spectra and allow for real-time, high-accuracy discrimination between the STN and substantia nigra pars reticulata. A support vector machine procedure was tested on microelectrode recordings from 58 trajectories that included both STN and substantia nigra pars reticulata that achieved a 97.6% consistency with human expert classification (evaluated by 10-fold cross-validation). We used the same data set as a training set to find the optimal parameters for a hidden Markov model using both microelectrode recording features and trajectory history to enable real-time classification of the ventral STN border (STN exit). Seventy-three additional trajectories were used to test the reliability of the learned statistical model in identifying the exit from the STN. The hidden Markov model procedure identified the STN exit with an error of 0.04 ± 0.18 mm and detection reliability (error < 1 mm) of 94%. The results indicate that robust, accurate, and automatic real-time electrophysiological detection of the ventral STN border is feasible. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

Real jet effects on dual jets in a crossflow

NASA Technical Reports Server (NTRS)

Schetz, J. A.

1984-01-01

A 6-ft by 6-ft wind tunnel section was modification to accommodate the 7-ft wide NASA dual-jet flate model in an effort to determine the effects of nonuniform and/or noncircular jet exhaust profiles on the pressure field induced on a nearby surface. Tests completed yield surface pressure measurements for a 90 deg circular injector producing exit profiles representative of turbofan nozzles (such as the TF-34 nozzle). The measurements were obtained for both tandem and side-by-side jet configurations, jet spacing of S/D =2, and velocity ratios of R=2.2 and 4.0. Control tests at the same mass flow rate but with uniform exit velocity profiles were also conducted, for comparison purposes. Plots for 90 deg injection and R=2.2 show that the effects of exit velocity profile nonuniformity are quite significant.

The exit-time problem for a Markov jump process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burch, N.; D'Elia, Marta; Lehoucq, Richard B.

2014-12-15

The purpose of our paper is to consider the exit-time problem for a finite-range Markov jump process, i.e, the distance the particle can jump is bounded independent of its location. Such jump diffusions are expedient models for anomalous transport exhibiting super-diffusion or nonstandard normal diffusion. We refer to the associated deterministic equation as a volume-constrained nonlocal diffusion equation. The volume constraint is the nonlocal analogue of a boundary condition necessary to demonstrate that the nonlocal diffusion equation is well-posed and is consistent with the jump process. A critical aspect of the analysis is a variational formulation and a recently developedmore » nonlocal vector calculus. Furthermore, this calculus allows us to pose nonlocal backward and forward Kolmogorov equations, the former equation granting the various moments of the exit-time distribution.« less

Double-pulse THz radiation bursts from laser-plasma acceleration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bosch, R. A.

2006-11-15

A model is presented for coherent THz radiation produced when an electron bunch undergoes laser-plasma acceleration and then exits axially from a plasma column. Radiation produced when the bunch is accelerated is superimposed with transition radiation from the bunch exiting the plasma. Computations give a double-pulse burst of radiation comparable to recent observations. The duration of each pulse very nearly equals the electron bunch length, while the time separation between pulses is proportional to the distance between the points where the bunch is accelerated and where it exits the plasma. The relative magnitude of the two pulses depends upon bymore » the radius of the plasma column. Thus, the radiation bursts may be useful in diagnosing the electron bunch length, the location of the bunch's acceleration, and the plasma radius.« less

Numerical simulations of a transverse indirect circulation and low-level jet in the exit region of an upper-level jet

NASA Technical Reports Server (NTRS)

Brill, K. F.; Uccellini, L. W.; Burkhart, R. P.; Warner, T. T.; Anthes, R. A.

1985-01-01

A numerical study was performed of a severe weather event (tornado) which occurred on May 10, 1973 in the Ohio region. The situation was modeled with a primitive equation mesoscale dynamic formulation. Account was taken of precipitation, the planetary boundary layer parameters as bulk quantities, the vertical pressure gradient, and lateral boundary conditions based on radiosonde data. Two 12-hr simulations, adiabatic and nondivergent, respectively, were analyzed for relationships between upper and lower level jets. In the adiabatic formulation, a transverse circulation with a low level jet formed at the exit region of the upper level jet. The nondivergent situation led to similar, but weaker, phenomena. Both forms suggest that indirect circulation in the exit zone of an upper level jet is strongly influenced by the initial structure of the jet.

Integrated CFD modeling of gas turbine combustors

NASA Technical Reports Server (NTRS)

Fuller, E. J.; Smith, C. E.

1993-01-01

3D, curvilinear, multi-domain CFD analysis is becoming a valuable tool in gas turbine combustor design. Used as a supplement to experimental testing. CFD analysis can provide improved understanding of combustor aerodynamics and used to qualitatively assess new combustor designs. This paper discusses recent advancements in CFD combustor methodology, including the timely integration of the design (i.e. CAD) and analysis (i.e. CFD) processes. Allied Signal's F124 combustor was analyzed at maximum power conditions. The assumption of turbulence levels at the nozzle/swirler inlet was shown to be very important in the prediction of combustor exit temperatures. Predicted exit temperatures were compared to experimental rake data, and good overall agreement was seen. Exit radial temperature profiles were well predicted, while the predicted pattern factor was 25 percent higher than the harmonic-averaged experimental pattern factor.

Wisconsin's BadgerCare Plus Reform: Impact on Low-Income Families' Enrollment and Retention in Public Coverage

PubMed Central

Leininger, Lindsey Jeanne; Friedsam, Donna; Dague, Laura; Mok, Shannon; Hynes, Emma; Bergum, Alison; Aksamitauskas, Milda; Oliver, Thomas; DeLeire, Thomas

2011-01-01

Objectives To examine the impact of a Wisconsin health care reform enacted in early 2008 on public insurance enrollment and retention. Data Sources Administrative data covering the period January 2007 to November 2009. Study Design We calculate unadjusted enrollment trends and exit rates stratified by age, income group, and enrollment mode. Kaplan–Meier curves and Cox proportional hazards models are estimated to assess the impact of the reform on program exits. Principal Findings Overall enrollment increased by approximately one-third and exit rates decreased by approximately one-fifth. The majority of new enrollment came from the previously income eligible. Conclusions Wisconsin's enactment of eligibility expansions coupled with administrative simplification and targeted marketing and outreach efforts were successful in enrolling and retaining low-income children and families in public coverage. PMID:21143476

Fluorescence Imaging of Rotational and Vibrational Temperature in a Shock Tunnel Nozzle Flow

NASA Technical Reports Server (NTRS)

Palma, Philip C.; Danehy, Paul M.; Houwing, A. F. P.

2003-01-01

Two-dimensional rotational and vibrational temperature measurements were made at the nozzle exit of a free-piston shock tunnel using planar laser-induced fluorescence. The Mach 7 flow consisted predominantly of nitrogen with a trace quantity of nitric oxide. Nitric oxide was employed as the probe species and was excited at 225 nm. Nonuniformities in the distribution of nitric oxide in the test gas were observed and were concluded to be due to contamination of the test gas by driver gas or cold test gas.The nozzle-exit rotational temperature was measured and is in reasonable agreement with computational modeling. Nonlinearities in the detection system were responsible for systematic errors in the measurements. The vibrational temperature was measured to be constant with distance from the nozzle exit, indicating it had frozen during the nozzle expansion.

NODA for EPA's Updated Ozone Transport Modeling

EPA Pesticide Factsheets

Find EPA's NODA for the Updated Ozone Transport Modeling Data for the 2008 Ozone National Ambient Air Quality Standard (NAAQS) along with the ExitExtension of Public Comment Period on CSAPR for the 2008 NAAQS.

Medicaid Expansion and ACA Repeal: Evidence From Ohio.

PubMed

Seiber, Eric E; Berman, Micah L

2017-06-01

To examine the health insurance coverage options for Medicaid expansion enrollees if the Affordable Care Act (ACA) is repealed, using evidence from Ohio, where more than half a million adults have enrolled in the state's Medicaid program through the ACA expansion. The Ohio Medicaid Assessment Survey interviewed 42 000 households in 2015. We report data from a unique battery of questions designed to identify insurance coverage immediately prior to Medicaid enrollment. Ninety-five percent of new Medicaid enrollees in Ohio did not have a private health insurance option immediately before enrollment. These new enrollees are predominantly older, low-income Whites with a high school education or less. Only 5% of new Medicaid enrollees were eligible for an employer-sponsored insurance plan to which they could potentially return in the case of repeal of the ACA. The vast majority of Medicaid expansion enrollees would have no plausible pathway to obtaining private-sector insurance if the ACA were repealed. Demographic similarities between the expansion population and 2016 exit polls suggest that coverage losses would fall disproportionately on members of the winning Republican coalition.

NASA/DERA Collaborative Program

NASA Technical Reports Server (NTRS)

Whitefield, Phillip D.; Hagen, Donald E.; Wormhoudt, Jody C.; Miake-Lye, Richard C.; Brundish, Kevin; Wilson, Christopher W.; Wey, Chowen (Technical Monitor)

2002-01-01

This report is an interim report. The work reported are the results from the combustor testing, the first phase of testing in the DERA/NASA collaborative program. A program of work was developed by DERA and NASA utilizing specialist facilities within the UK, and specialist measurement techniques developed within the U.S. Under a Memorandum of Understanding (MoU) between the UK and U.S. governments, the joint UK/U.S. funded program commenced. The objective of the program was to make combustor and engine exit plane emissions measurements, including particulate and sulphur measurements, for kerosene fuels with different sulphur levels. The combustor test program was performed in August/September 2000. Although probe issues complicated the test program, a consistent set of data, including CO, NO(x), NO, NO2, CO2, O2, smoke number, particulate number density and size distribution, SO2, SO3 and HONO were collected at the exit plane of the DERA TRACE engine combustor. A second probe was utilized to measure spatial location of CO, NO(x), NO, NO2 and CO2 concentrations. Data are therefore available for development of aerosol, particulate and aerosol precursor chemistry sub-models for inclusion into CFD. Inlet boundary conditions have been derived at the exit of the combustion system for the modelling of the DERA TRACE engine. The second phase of the program is to perform identical measurements at the engine exit, to allow a full data set to be available. This will be performed in July 2001 at the Glenn test facility, DERA Pyestock.

A thermostatted kinetic theory model for event-driven pedestrian dynamics

NASA Astrophysics Data System (ADS)

Bianca, Carlo; Mogno, Caterina

2018-06-01

This paper is devoted to the modeling of the pedestrian dynamics by means of the thermostatted kinetic theory. Specifically the microscopic interactions among pedestrians and an external force field are modeled for simulating the evacuation of pedestrians from a metro station. The fundamentals of the stochastic game theory and the thermostatted kinetic theory are coupled for the derivation of a specific mathematical model which depicts the time evolution of the distribution of pedestrians at different exits of a metro station. The perturbation theory is employed in order to establish the stability analysis of the nonequilibrium stationary states in the case of a metro station consisting of two exits. A general sensitivity analysis on the initial conditions, the magnitude of the external force field and the number of exits is presented by means of numerical simulations which, in particular, show how the asymptotic distribution and the convergence time are affected by the presence of an external force field. The results show how, in evacuation conditions, the interaction dynamics among pedestrians can be negligible with respect to the external force. The important role of the thermostat term in allowing the reaching of the nonequilibrium stationary state is stressed out. Research perspectives are underlined at the end of paper, in particular for what concerns the derivation of frameworks that take into account the definition of local external actions and the introduction of the space and velocity dynamics.

Perspectives of Youth in Foster Care on Essential Ingredients for Promoting Self-determination and Successful Transition to Adult Life: My Life Model.

PubMed

Powers, Laurie E; Fullerton, Ann; Schmidt, Jessica; Geenen, Sarah; Oberweiser-Kennedy, Molly; Dohn, JoAnn; Nelson, May; Iavanditti, Rosemary; Blakeslee, Jennifer

2018-02-01

Research clearly documents the serious challenges and poor outcomes experienced by many young people exiting foster care, as well as compounded disparities for the high percentage of youth in care who are identified with disabilities and/or mental health challenges. However, very little research has been conducted to specify or validate effective models for improving the transition trajectories of youth exiting care. Evidence suggests the My Life self-determination enhancement model offers a promising approach for supporting youths' self-determined and positive transition to adulthood. The model includes youth-directed, experientially oriented coaching in the application of self-determination skills to achieve youth-identified transition goals, coupled with peer mentoring workshops that provide opportunities for learning, networking and fun. This in depth qualitative study of 10 youth who completed the My Life intervention focused on investigating coaching and mentoring elements and processes that youth participants identify as most important to their success, with the intention of informing the further development of youth-directed approaches to supporting young people who are transitioning to adulthood. Themes emerged around the centrality of youth self-direction, important processes in the coaching relationship, the essential value of experiential activities and self-determination skill development, and peer mentoring experiences that youth identified as fostering their success. Implications are discussed for research and practice in supporting youth exiting foster care.

Radiation Dose Uncertainty and Correction for a Mouse Orthotopic and Xenograft Irradiation Model

PubMed Central

Gan, Gregory N.; Altunbas, Cem; Morton, John J.; Eagles, Justin; Backus, Jennifer; Dzingle, Wayne; Raben, David; Jimeno, Antonio

2016-01-01

Purpose In animal irradiation models, reported dose can vary significantly from the actual doses delivered. We describe an effective method for in vivo dose verification. Materials and Methods Mice bearing commercially-available cell line or patient-derived tumor cell orthotopic or flank xenografts were irradiated using a 160 kVp, 25 mA X-ray source. Entrance dose was evaluated using optically-stimulated luminescence dosimeters (OSLD) and exit dose was assessed using radiochromic film dosimetry. Results Tumor position within the irradiation field was validated using external fiducial markers. The average entrance dose in orthotopic tumors from 10 OSLDs placed on 2 different animal irradiation days was 514±37 cGy (range: 437–545). Exit dose measurements taken from 7 radiochromic films on two separate days were 341±21 cGy (a 34% attenuation). Flank tumor irradiation doses measured by OSLD were 368±9 cGy compared to exit doses of 330 cGy measured by radiochromic film. Conclusion Variations related to the irradiation model can lead to significant under or over- dosing in vivo which can affect tumor control and/or biologic endpoints that are dose dependent. We recommend that dose measurements be determined empirically based on the mouse model and irradiator used and dose compensation adjustments performed to ensure correct and appropriate doses. PMID:26689828

Emissions Prediction and Measurement for Liquid-Fueled TVC Combustor with and without Water Injection

NASA Technical Reports Server (NTRS)

Brankovic, A.; Ryder, R. C., Jr.; Hendricks, R. C.; Liu, N.-S.; Shouse, D. T.; Roquemore, W. M.

2005-01-01

An investigation is performed to evaluate the performance of a computational fluid dynamics (CFD) tool for the prediction of the reacting flow in a liquid-fueled combustor that uses water injection for control of pollutant emissions. The experiment consists of a multisector, liquid-fueled combustor rig operated at different inlet pressures and temperatures, and over a range of fuel/air and water/fuel ratios. Fuel can be injected directly into the main combustion airstream and into the cavities. Test rig performance is characterized by combustor exit quantities such as temperature and emissions measurements using rakes and overall pressure drop from upstream plenum to combustor exit. Visualization of the flame is performed using gray scale and color still photographs and high-frame-rate videos. CFD simulations are performed utilizing a methodology that includes computer-aided design (CAD) solid modeling of the geometry, parallel processing over networked computers, and graphical and quantitative post-processing. Physical models include liquid fuel droplet dynamics and evaporation, with combustion modeled using a hybrid finite-rate chemistry model developed for Jet-A fuel. CFD and experimental results are compared for cases with cavity-only fueling, while numerical studies of cavity and main fueling was also performed. Predicted and measured trends in combustor exit temperature, CO and NOx are in general agreement at the different water/fuel loading rates, although quantitative differences exist between the predictions and measurements.

29 CFR 1917.122 - Employee exits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Employee exits. 1917.122 Section 1917.122 Labor Regulations...) MARINE TERMINALS Terminal Facilities § 1917.122 Employee exits. (a) Employee exits shall be clearly marked. (b) If an employee exit is not visible from employees' work stations, directional signs...

Advanced Diesel Oil Fuel Processor Development

DTIC Science & Technology

1986-06-01

water exit 29 sample quencher: gas sample line inlet 30 sample quencher: gas sample line exit 31 sample quencher: cooling water inlet 32 desulfuriser ...exit line 33, 34 desulfurimer 35 heat exchanger: process gas exit (to desulfuriser ) 38 shift reactor inlet (top) 37 shift reactor: cooling air exit

Association between keeping home records of catheter exit-site and incidence of peritoneal dialysis-related infections.

PubMed

Iida, Hidekazu; Kurita, Noriaki; Fujimoto, Shino; Kamijo, Yuka; Ishibashi, Yoshitaka; Fukuma, Shingo; Fukuhara, Shunichi

2018-04-01

To prevent peritoneal dialysis (PD)-related infection, components of self-catheter care have been emphasized. However, studies on the effectiveness of home recording for the prevention of PD-related infections are limited. This study aimed to examine the association between keeping home records of catheter exit site and incidence of PD-related infections. Home record books were submitted by patients undergoing PD. The proportion of days on which exit-site home recording was carried out for 120 days (0-100%) was obtained. The patients were divided into the frequent home recording group (≥ 40.5%; median value) and the infrequent home recording group (< 40.5%). The associations between the recording group and the incidence rate ratios (IRRs) of PD-related infections were estimated via negative binomial regression models. A total of 67 patients participated in this study (mean age, 66.7 years). The incidence rates for exit-site infection, tunnel infection, and peritonitis were 0.42, 0.22, and 0.06 times/patient-year, respectively. The IRRs of the frequent versus infrequent home recording groups for PD-related infection were 1.58 (95% confidence interval [CI], 0.72-3.46) in the univariate analysis and 1.49 (95% CI, 0.65-3.42) in the multivariate analysis. The IRRs of the frequent versus infrequent home recording groups for composite of surgery to create a new exit site and removal of PD catheter were 0.55 (95% CI, 0.78-3.88) and 0.35 (95% CI, 0.06-1.99), respectively. This study could not prove that keeping home records of patients' catheter exit site is associated with a lower incidence of PD-related infections.

3D Building Evacuation Route Modelling and Visualization

NASA Astrophysics Data System (ADS)

Chan, W.; Armenakis, C.

2014-11-01

The most common building evacuation approach currently applied is to have evacuation routes planned prior to these emergency events. These routes are usually the shortest and most practical path from each building room to the closest exit. The problem with this approach is that it is not adaptive. It is not responsively configurable relative to the type, intensity, or location of the emergency risk. Moreover, it does not provide any information to the affected persons or to the emergency responders while not allowing for the review of simulated hazard scenarios and alternative evacuation routes. In this paper we address two main tasks. The first is the modelling of the spatial risk caused by a hazardous event leading to choosing the optimal evacuation route for a set of options. The second is to generate a 3D visual representation of the model output. A multicriteria decision making (MCDM) approach is used to model the risk aiming at finding the optimal evacuation route. This is achieved by using the analytical hierarchy process (AHP) on the criteria describing the different alternative evacuation routes. The best route is then chosen to be the alternative with the least cost. The 3D visual representation of the model displays the building, the surrounding environment, the evacuee's location, the hazard location, the risk areas and the optimal evacuation pathway to the target safety location. The work has been performed using ESRI's ArcGIS. Using the developed models, the user can input the location of the hazard and the location of the evacuee. The system then determines the optimum evacuation route and displays it in 3D.

Spatial correlation in the ambient core noise field of a turbofan engine.

PubMed

Miles, Jeffrey Hilton

2012-06-01

An acoustic transfer function relating combustion noise and turbine exit noise in the presence of enclosed ambient core noise is investigated using a dynamic system model and an acoustic system model for the particular turbofan engine studied and for a range of operating conditions. Measurements of cross-spectra magnitude and phase between the combustor and turbine exit and auto-spectra at the turbine exit and combustor are used to show the presence of indirect and direct combustion noise over the frequency range of 0-400 Hz. The procedure used evaluates the ratio of direct to indirect combustion noise. The procedure used also evaluates the post-combustion residence time in the combustor which is a factor in the formation of thermal NO(x) and soot in this region. These measurements are masked by the ambient core noise sound field in this frequency range which is observable since the transducers are situated within an acoustic wavelength of one another. An ambient core noise field model based on one and two dimensional spatial correlation functions is used to replicate the spatially correlated response of the pair of transducers. The spatial correlation function increases measured attenuation due to destructive interference and masks the true attenuation of the turbine.

Effect of Velocity and Temperature Distribution at the Hole Exit on Film Cooling of Turbine Blades

NASA Technical Reports Server (NTRS)

Garg, V. K.; Gaugler, R. E.

1997-01-01

An existing three-dimensional Navier-Stokes code (Arnone et al, 1991), modified Turbine Branch, to include film cooling considerations (Garg and Gaugler, 1994), has been used to study the effect of coolant velocity and temperature distribution at the hole exit on the heat transfer coefficient on three film-cooled turbine blades, namely, the C3X vane, the VKI rotor, and the ACE rotor. Results are also compared with the experimental data for all the blades. Moreover, Mayle's transition criterion (1991), Forest's model for augmentation of leading edge heat transfer due to free-stream turbulence (1977), and Crawford's model for augmentation of eddy viscosity due to film cooling (Crawford et al, 1980) are used. Use of Mayle's and Forest's models is relevant only for the ACE rotor due to the absence of showerhead cooling on this rotor. It is found that, in some cases, the effect of distribution of coolant velocity and temperature at the hole exit can be as much as 60 percent on the heat transfer coefficient at the blade suction surface, and 50 percent at the pressure surface. Also, different effects are observed on the pressure and suction surface depending upon the blade as well as upon the hole shape, conical or cylindrical.

Species and temperature measurement in H2/O2 rocket flow fields by means of Raman scattering diagnostics

NASA Technical Reports Server (NTRS)

Degroot, Wim A.; Weiss, Jonathan M.

1992-01-01

Validation of Computational Fluid Dynamics (CFD) codes developed for prediction and evaluation of rocket performance is hampered by a lack of experimental data. Non-intrusive laser based diagnostics are needed to provide spatially and temporally resolved gas dynamic and fluid dynamic measurements. This paper reports the first non-intrusive temperature and species measurements in the plume of a 110 N gaseous hydrogen/oxygen thruster at and below ambient pressures, obtained with spontaneous Raman spectroscopy. Measurements at 10 mm downstream of the exit plane are compared with predictions from a numerical solution of the axisymmetric Navier-Stokes and species transport equations with chemical kinetics, which fully model the combustor-nozzle-plume flowfield. The experimentally determined oxygen number density at the centerline at 10 mm downstream of the exit plane is four times that predicted by the model. The experimental number density data fall between those numerically predicted for the exit and 10 mm downstream planes in both magnitude and radial gradient. The predicted temperature levels are within 10 to 15 percent of measured values. Some of the discrepancies between experimental data and predictions result from not modeling the three dimensional core flow injection mixing process, facility back pressure effects, and possible diffuser-thruster interactions.

Effects of nozzle exit geometry and pressure ratio on plume shape for nozzles exhausting into quiescent air

NASA Technical Reports Server (NTRS)

Scallion, William I.

1991-01-01

The effects of varying the exit geometry on the plume shapes of supersonic nozzles exhausting into quiescent air at several exit-to-ambient pressure ratios are given. Four nozzles having circular throat sections and circular, elliptical and oval exit cross sections were tested and the exit plume shapes are compared at the same exit-to-ambient pressure ratios. The resulting mass flows were calculated and are also presented.

14 CFR 27.805 - Flight crew emergency exits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight crew emergency exits. 27.805 Section... § 27.805 Flight crew emergency exits. (a) For rotorcraft with passenger emergency exits that are not convenient to the flight crew, there must be flight crew emergency exits, on both sides of the rotorcraft or...

14 CFR 29.805 - Flight crew emergency exits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Flight crew emergency exits. 29.805 Section... Accommodations § 29.805 Flight crew emergency exits. (a) For rotorcraft with passenger emergency exits that are not convenient to the flight crew, there must be flight crew emergency exits, on both sides of the...

14 CFR 29.805 - Flight crew emergency exits.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight crew emergency exits. 29.805 Section... Accommodations § 29.805 Flight crew emergency exits. (a) For rotorcraft with passenger emergency exits that are not convenient to the flight crew, there must be flight crew emergency exits, on both sides of the...

14 CFR 27.805 - Flight crew emergency exits.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Flight crew emergency exits. 27.805 Section... § 27.805 Flight crew emergency exits. (a) For rotorcraft with passenger emergency exits that are not convenient to the flight crew, there must be flight crew emergency exits, on both sides of the rotorcraft or...

A fuzzy-theory-based behavioral model for studying pedestrian evacuation from a single-exit room

NASA Astrophysics Data System (ADS)

Fu, Libi; Song, Weiguo; Lo, Siuming

2016-08-01

Many mass events in recent years have highlighted the importance of research on pedestrian evacuation dynamics. A number of models have been developed to analyze crowd behavior under evacuation situations. However, few focus on pedestrians' decision-making with respect to uncertainty, vagueness and imprecision. In this paper, a discrete evacuation model defined on the cellular space is proposed according to the fuzzy theory which is able to describe imprecise and subjective information. Pedestrians' percept information and various characteristics are regarded as fuzzy input. Then fuzzy inference systems with rule bases, which resemble human reasoning, are established to obtain fuzzy output that decides pedestrians' movement direction. This model is tested in two scenarios, namely in a single-exit room with and without obstacles. Simulation results reproduce some classic dynamics phenomena discovered in real building evacuation situations, and are consistent with those in other models and experiments. It is hoped that this study will enrich movement rules and approaches in traditional cellular automaton models for evacuation dynamics.

Pedestrians’ behavior in emergency evacuation: Modeling and simulation

NASA Astrophysics Data System (ADS)

Wang, Lei; Zheng, Jie-Hui; Zhang, Xiao-Shuang; Zhang, Jian-Lin; Wang, Qiu-Zhen; Zhang, Qian

2016-11-01

The social force model has been widely used to simulate pedestrian evacuation by analyzing attractive, repulsive, driving, and fluctuating forces among pedestrians. Many researchers have improved its limitations in simulating behaviors of large-scale population. This study modifies the well-accepted social force model by considering the impacts of interaction among companions and further develops a comprehensive model by combining that with a multi-exit utility function. Then numerical simulations of evacuations based on the comprehensive model are implemented in the waiting hall of the Wulin Square Subway Station in Hangzhou, China. The results provide safety thresholds of pedestrian density and panic levels in different operation situations. In spite of the operation situation and the panic level, a larger friend-group size results in lower evacuation efficiency. Our study makes important contributions to building a comprehensive multi-exit social force model and to applying it to actual scenarios, which produces data to facilitate decision making in contingency plans and emergency treatment. Project supported by the National Natural Science Foundation of China (Grant No. 71471163).

Ambulatory surgery center and general hospital competition: entry decisions and strategic choices.

PubMed

Al-Amin, Mona; Housman, Michael

2012-01-01

General hospitals are consistently under pressure to control cost and improve quality. In addition to mounting payers' demands, hospitals operate under evolving market conditions that might threaten their survival. While hospitals traditionally were concerned mainly with competition from other hospitals, today's reimbursement schemes and entrepreneurial activities encouraged the proliferation of outpatient facilities such as ambulatory surgery centers (ASCs) that can jeopardize hospitals' survival. The purpose of this article was to examine the relationship between ASCs and general hospitals. More specifically, we apply the niche overlap theory to study the impact that competition between ASCs and general hospitals has on the survival chances of both of these organizational populations. Our analysis examined interpopulation competition in models of organizational mortality and market demand. We utilized Cox proportional hazard models to evaluate the impact of competition from each on ASC and hospital exit while controlling for market factors. We relied on two data sets collected and developed by Florida's Agency for Health Care Administration: outpatient facility licensure data and inpatient and outpatient surgical procedure data. Although ASCs do tend to exit markets in which there are high levels of ASC competition, we found no evidence to suggest that ASC exit rates are affected by hospital density. On the other hand, hospitals not only tend to exit markets with high levels of hospital competition but also experience high exit rates in markets with high ASC density. The implications from our study differ for ASCs and hospitals. When making decisions about market entry, ASCs should choose their markets according to the following: demand for outpatient surgery, number of physicians who would practice in the surgery center, and the number of surgery centers that already exist in the market. Hospitals, on the other hand, should account for competition from ASCs while making market-entry decisions and while developing their strategic plans.

Reduction of background noise induced by wind tunnel jet exit vanes

NASA Technical Reports Server (NTRS)

Martin, R. M.; Brooks, T. F.; Hoad, D. R.

1985-01-01

The NASA-Langley 4 x 7 m wind tunnel develops low frequency flow pulsations at certain velocity ranges during open throat mode operation, affecting the aerodynamics of the flow and degrading the resulting model test data. Triangular vanes attached to the trailing edge of flat steel rails, mounted 10 cm from the inside of the jet exit walls, have been used to reduce this effect; attention is presently given to methods used to reduce the inherent noise generation of the vanes while retaining their pulsation reduction features.

Early Universe synthesis of asymmetric dark matter nuggets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gresham, Moira I.; Lou, Hou Keong; Zurek, Kathryn M.

We compute the mass function of bound states of asymmetric dark matter - nuggets - synthesized in the early Universe. We apply our results for the nugget density and binding energy computed from a nuclear model to obtain analytic estimates of the typical nugget size exiting synthesis. We numerically solve the Boltzmann equation for synthesis including two-to-two fusion reactions, estimating the impact of bottlenecks on the mass function exiting synthesis. These results provide the basis for studying the late Universe cosmology of nuggets in a future companion paper.

Early Universe synthesis of asymmetric dark matter nuggets

DOE PAGES

Gresham, Moira I.; Lou, Hou Keong; Zurek, Kathryn M.

2018-02-12

We compute the mass function of bound states of asymmetric dark matter - nuggets - synthesized in the early Universe. We apply our results for the nugget density and binding energy computed from a nuclear model to obtain analytic estimates of the typical nugget size exiting synthesis. We numerically solve the Boltzmann equation for synthesis including two-to-two fusion reactions, estimating the impact of bottlenecks on the mass function exiting synthesis. These results provide the basis for studying the late Universe cosmology of nuggets in a future companion paper.

Early Universe synthesis of asymmetric dark matter nuggets

NASA Astrophysics Data System (ADS)

Gresham, Moira I.; Lou, Hou Keong; Zurek, Kathryn M.

2018-02-01

We compute the mass function of bound states of asymmetric dark matter—nuggets—synthesized in the early Universe. We apply our results for the nugget density and binding energy computed from a nuclear model to obtain analytic estimates of the typical nugget size exiting synthesis. We numerically solve the Boltzmann equation for synthesis including two-to-two fusion reactions, estimating the impact of bottlenecks on the mass function exiting synthesis. These results provide the basis for studying the late Universe cosmology of nuggets in a future companion paper.

Chemoattractant receptors and lymphocyte egress from extralymphoid tissue: changing requirements during the course of inflammation1

PubMed Central

Brown, Meghan N.; Fintushel, Sarah R.; Lee, Michael H.; Jennrich, Silke; Geherin, Skye A.; Hay, John B.; Butcher, Eugene C.; Debes, Gudrun F.

2012-01-01

Memory/effector T cells traffic efficiently through extralymphoid tissues, entering from the blood and leaving via the afferent lymph. During inflammation, T cell traffic into the affected tissue dramatically increases; however, the dynamics and mechanisms of T cell exit from inflamed tissues are poorly characterized. Here we show, using both a mouse and a sheep model, that large numbers of lymphocytes leave the chronically inflamed skin. Many T cells capable of producing IFN-γ and IL-17 also entered the draining afferent lymph, demonstrating that memory/effector T cells egress from sites of inflammation. Whereas efficient egress from acutely inflamed skin required lymphocyte-expressed CCR7, chronic inflammation promoted significant CCR7-independent exit as well. Lymphocyte exit at late time points of inflammation was sensitive to pertussis toxin but only partially affected by the drug FTY720, implying the contribution of alternative chemoattractant receptors other than S1P1. Our data show that CCR7 is an important receptor for lymphocyte egress from both resting and inflamed extralymphoid tissues, but that alternative exit receptors come into play during chronic inflammation. PMID:20833836

Factors affecting physician loyalty and exit: a longitudinal analysis of physician-hospital relationships.

PubMed Central

Burns, L R; Wholey, D R

1992-01-01

This article examines forces that influence physicians to change the percentage of their admissions to a hospital (loyalty) and to cease admitting patients to a hospital altogether (exit). Because physicians are both members of a hospital and consumers of its services, their admitting patterns can be described using models of employee commitment and consumer buying behavior. We test several hypotheses drawn from these literatures using data on physician admissions at hospitals over a two-year period. Results indicate that admitting patterns are explained primarily by convenience and inertia processes characteristic of consumer behavior. On the other hand, factors believed to influence organizational commitment (e.g., decision-making involvement, conflict, economic investments) have little effect on loyalty and exit. The findings question the utility of hospital strategies to improve the climate of physician-hospital relations, and suggest several qualifications for research on the commitment of professionals. PMID:1563950

The reverse laser drilling of transparent materials

NASA Technical Reports Server (NTRS)

Anthony, T. R.; Lindner, P. A.

1980-01-01

Within a limited range of incident laser-beam intensities, laser drilling of a sapphire wafer initiates on the surface of the wafer where the laser beam exits and proceeds upstream in the laser beam to the surface where the laser beam enters the wafer. This reverse laser drilling is the result of the constructive interference between the laser beam and its reflected component on the exit face of the wafer. Constructive interference occurs only at the exit face of the sapphire wafer because the internally reflected laser beam suffers no phase change there. A model describing reverse laser drilling predicts the ranges of incident laser-beam intensity where no drilling, reverse laser drilling, and forward laser drilling can be expected in various materials. The application of reverse laser drilling in fabricating feed-through conductors in silicon-on-sapphire wafers for a massively parallel processer is described.

Observation of strong reflection of electron waves exiting a ballistic channel at low energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaz, Canute I.; Campbell, Jason P.; Ryan, Jason T.

2016-06-15

Wave scattering by a potential step is a ubiquitous concept. Thus, it is surprising that theoretical treatments of ballistic transport in nanoscale devices, from quantum point contacts to ballistic transistors, assume no reflection even when the potential step is encountered upon exiting the device. Experiments so far seem to support this even if it is not clear why. Here we report clear evidence of coherent reflection when electron wave exits the channel of a nanoscale transistor and when the electron energy is low. The observed behavior is well described by a simple rectangular potential barrier model which the Schrodinger’s equationmore » can be solved exactly. We can explain why reflection is not observed in most situations but cannot be ignored in some important situations. Our experiment also represents a direct measurement of electron injection velocity - a critical quantity in nanoscale transistors that is widely considered not measurable.« less

Who wants to be a surgeon? Patterns of medical student career choice.

PubMed

Shirley, Otis C; Addison, Ben; Poole, Phillippa

2014-11-07

NZ needs a surgical workforce with the capacity to meet the increasing health demands of an aging population. This study determined longitudinal patterns of medical student interest in a surgical career and factors influencing that choice. We studied medical students entering the Auckland medical programme from 2006-2008 who completed an entry and exit questionnaire on career intentions. Four notional groups were created, depending on the level of interest at entry and at exit. Demographic factors for each category were compared. Analysis of influencing factors was also undertaken. Of 488 students, 310 (64%) completed both an entry and exit questionnaire. Over 50% of students had a strong interest in a surgical career at entry, dropping to 26% at exit. The 'Never Evers' (No interest at entry /No interest at exit) made up 39%,'Divergers' (Strong/No) 35%, 'Die Hards' (Strong/Strong) 18%, and 'Convertibles' (No/Strong) 8%. Less interest in a surgical career was seen among female (P=0.001) and older students (P=0.017). Influencing factors differentiating the 'Die Hards' from the 'Divergers' were work hours and flexibility (less influence among 'Die Hards'), with procedural nature and consultants/mentors (higher). There is a significant reduction in interest in a surgical career over the course of the undergraduate programme, especially among female and older students. Yet the level appears sufficient for available training places. Consultant role models are an important career influence. Lack of flexibility in work and training programmes continue to provide challenges in creating a diverse surgical workforce.

Do spouses coordinate their work exits? A combined survey and register analysis from Norway.

PubMed

Syse, Astri; Solem, Per Erik; Ugreninov, Elisabeth; Mykletun, Reidar; Furunes, Trude

2014-09-01

Research on spouses' joint work exits is scarce, although household factors such as spouses' work status, marital quality, and caregiving burdens are likely to affect seniors' work engagement. We therefore examine whether the work exit probability of one spouse affects that of the other. Discrete-time hazard regression analyses of survey data linked to later registry information including all gainfully employed married respondents aged 50-74 with a working spouse (N = 1,764) were used to assess subsequent work exits. A spouse's work exit is a strong predictor of a respondent's work exit (hazard ratio 3.1, 95% confidence interval [2.5, 4.0]). Educational attainment, poor marital quality, and spouses' health and care needs do not predict work exits. Surprisingly, no gender differences are observed. Research on larger survey samples to distinguish different work exit routes and reasons for spouses' joint work exits appears warranted. To account for cultural and welfare state characteristics, cross-national studies ought to be undertaken. © The Author(s) 2013.

A Hydrogen Peroxide Hot-Jet Simulator for Wind-Tunnel Tests of Turbojet-Exit Models

NASA Technical Reports Server (NTRS)

Runckel, Jack F.; Swihart, John M.

1959-01-01

A turbojet-engine-exhaust simulator which utilizes a hydrogen peroxide gas generator has been developed for powered-model testing in wind tunnels with air exchange. Catalytic decomposition of concentrated hydrogen peroxide provides a convenient and easily controlled method of providing a hot jet with characteristics that correspond closely to the jet of a gas turbine engine. The problems associated with simulation of jet exhausts in a transonic wind tunnel which led to the selection of a liquid monopropellant are discussed. The operation of the jet simulator consisting of a thrust balance, gas generator, exit nozzle, and auxiliary control system is described. Static-test data obtained with convergent nozzles are presented and shown to be in good agreement with ideal calculated values.

Performance Characteristics of Flush and Shielded Auxiliary Exits at Mach Numbers of 1.5 to 2.0

NASA Technical Reports Server (NTRS)

Abdalla, Kaleel L.

1959-01-01

The performance characteristics of several flush and shielded auxiliary exits were investigated at Mach numbers of 1.5 to 2.0, and jet pressure ratios from jet off to 10. The results indicate that the shielded configurations produced better overall performance than the corresponding flush exits over the Mach-number and pressure-ratio ranges investigated. Furthermore, the full-length shielded exit was highest in performance of all the configurations. The flat-exit nozzle block provided considerably improved performance compared with the curved-exit nozzle block.

A Three-Dimensional CFD Investigation of Secondary Flow in an Accelerating, 90 deg Elbow

NASA Technical Reports Server (NTRS)

Cavicchi, Richard H.

2001-01-01

NASA Glenn Research Center has recently applied the WIND National Code flow solver to an accelerating elbow with a 90 deg. bend to reveal aspects of secondary flow. This elbow was designed by NACA in the early 1950's such that flow separation would be avoided. Experimental testing was also done at that time. The current three dimensional CFD investigation shows that separation has indeed been avoided. Using its three-dimensional capability, this investigation provides various viewpoints in several planes that display the inception, development, and final location of a passage vortex. Its shape first becomes discernible as a vortex near the exit of the bend. This rendition of the exit passage vortex compares well with that found in the experiments. The viewpoints show that the passage vortex settles on the suction surface at the exit about one-third of the distance between the plane wall and midspan. Furthermore, it projects into the mainstream to about one-third of the channel width. Of several turbulence models used in this investigation, the Spalart Alimaras, Baldwin Lomax, and SST (Shear Stress Transport) models were by far the most successful in matching the experiments.

Internal Performance of a Fixed-Shroud Nonaxisymmetric Nozzle Equipped with an Aft-Hood Exhaust Deflector

NASA Technical Reports Server (NTRS)

Asbury, Scott C.

1997-01-01

An investigation was conducted in the model preparation area of the Langley 16-Foot Transonic Tunnel to determine the internal performance of a fixed-shroud nonaxisymmetric nozzle equipped with an aft-hood exhaust deflector. Model geometric parameters investigated included nozzle power setting, aft-hood deflector angle, throat area control with the aft-hood deflector deployed, and yaw vector angle. Results indicate that cruise configurations produced peak performance in the range consistent with previous investigations of nonaxisymmetric convergent-divergent nozzles. The aft-hood deflector produced resultant pitch vector angles that were always less than the geometric aft-hood deflector angle when the nozzle throat was positioned upstream of the deflector exit. Significant losses in resultant thrust ratio occurred when the aft-hood deflector was deployed with an upstream throat location. At each aft-hood deflector angle, repositioning the throat to the deflector exit improved pitch vectoring performance and, in some cases, substantially improved resultant thrust ratio performance. Transferring the throat to the deflector exit allowed the flow to be turned upstream of the throat at subsonic Mach numbers, thereby eliminating losses associated with turning supersonic flow. Internal throat panel deflections were largely unsuccessful in generating yaw vectoring.

A frictionally and hydraulically constrained model of the convectively driven mean flow in partially enclosed seas

NASA Astrophysics Data System (ADS)

Maxworthy, T.

1997-08-01

A simple three-layer model of the dynamics of partially enclosed seas, driven by a surface buoyancy flux, is presented. It contains two major elements, a hydraulic constraint at the exit contraction and friction in the interior of the main body of the sea; both together determine the vertical structure and magnitudes of the interior flow variables, i.e. velocity and density. Application of the model to the large-scale dynamics of the Red Sea gives results that are not in disagreement with observation once the model is applied, also, to predict the dense outflow from the Gulf of Suez. The latter appears to be the agent responsible for the formation of dense bottom water in this system. Also, the model is reasonably successful in predicting the density of the outflow from the Persian Gulf, and can be applied to any number of other examples of convectively driven flow in long, narrow channels, with or without sills and constrictions at their exits.

Ion-driven wind: Aerodynamics, performance limits, and optimization

NASA Astrophysics Data System (ADS)

Rickard, Matthew James Alan

When a strong electric field is generated between a sharp, charged object and a grounded electrode in a gas medium, ions that are generated via a corona discharge near the tip of the sharp object migrate to the electrical ground, setting the neutral hulk gas in motion. The strength of the flow generated from such a process; known as a "corona", "ionic", or "ion-driven" wind, increases with electric field until electrical breakdown is reached. Previous studies have found an upper bound on the velocity of the ion-driven wind, even when a series of electrode stages are aggregated. With the intent of maximizing the gas flow front such devices, this dissertation describes a series of experiments that have been conducted and a numerical model that has been employed. Although typical hardware configurations include a wire parallel to a plate, a wire placed concentrically within a cylinder, or a needle facing a perpendicular plate or mesh, the chosen setup for this study is a needle facing a concentric ring. Using multiple experimental techniques and numerical simulation, velocity profiles have been observed at the ring exit and are sensitive to the design of the mounting hardware. The numerical model predicts the ideal electrode geometry for maximizing flow through a single unit. A modular, multi-staged system has been constructed and, when loaded with an exit nozzle, the exit velocity can be substantially increased. Further, if a small-scale (sub-millimeter) system is created, it is expected that the velocity will increase with multi-staging, even in the absence of an exit nozzle.

Design and Off-design Performance of 100 Kwe-class Brayton Power Conversion Systems

NASA Technical Reports Server (NTRS)

Johnson, Paul K.; Mason, Lee S.

2005-01-01

The NASA Glenn Research Center in-house computer model Closed Cycle Engine Program (CCEP) was used to explore the design trade space and off-design performance characteristics of 100 kWe-class recuperated Closed Brayton Cycle (CBC) power conversion systems. Input variables for a potential design point included the number of operating units (1, 2, 4), cycle peak pressure (0.5, 1, 2 MPa), and turbo-alternator shaft speed (30, 45, 60 kRPM). The design point analysis assumed a fixed turbine inlet temperature (1150 K), compressor inlet temperature (400 K), working-fluid molecular weight (40 g/mol), compressor pressure ratio (2.0), recuperator effectiveness (0.95), and a Sodium-Potassium (NaK) pumped-loop radiator. The design point options were compared on the basis of thermal input power, radiator area, and mass. For a nominal design point with defined Brayton components and radiator area, off-design cases were examined by reducing turbine inlet temperature (as low as 900 K), reducing shaft speed (as low as 50% of nominal), and circulating a percentage (up to 20%) of the compressor exit flow back to the gas cooler. The off-design examination sought approaches to reduce thermal input power without freezing the radiator.

Pratt & Whitney 2D Model in LeRC 9 ft x 15 ft Acoustics

NASA Technical Reports Server (NTRS)

Bridges, James; Marino, Jodilyn

1999-01-01

The theory of mixer-ejectors for noise suppression is illustrated in this cartoon. Since jet noise SPL scales as velocity to the eighth power and diameter squared, increasing the jet diameter while lowering its velocity and keeping thrust constant decreases the noise. However, in supersonic craft, the drag penalty for increasing diameter at supersonic cruise makes this option very expensive. One would like to have a large engine during takeoff which could be shrunk during cruise. The retractable ejector is such an expandable engine. If the mixer flow can be expanded to the size of the ejector exit, the noise generated downstream of the ejector will be much less than the small diameter mixer nozzle alone. Of course, this also requires that the noise created in expanding the flow to fill the ejector be absorbed by a liner in the ejector walls so that none of this noise is heard. Since this mixing of internal hot gas and external cold air must take place in as short a distance as possible, the mixer must be very effective and therefore probably much noisier than a simple nozzle.

Examining the effects of turnover intentions on organizational citizenship behaviors and deviance behaviors: A psychological contract approach.

PubMed

Mai, Ke Michael; Ellis, Aleksander P J; Christian, Jessica Siegel; Porter, Christopher O L H

2016-08-01

Although turnover intentions are considered the most proximal antecedent of organizational exit, there is often temporal separation between thinking about leaving and actual exit. Using field data from 2 diverse samples of working adults, we explore a causal model of the effects of turnover intentions on employee behavior while they remain with the organization, focusing specifically on organizational citizenship behaviors (OCBs) and deviance behaviors (DBs). Utilizing expectancy theory as an explanatory framework, we argue that turnover intentions result in high levels of transactional contract orientation and low levels of relational contract orientation, which in turn lead to a decrease in the incidence of OCBs and an increase in the incidence of DBs. We first used a pilot study to investigate the direction of causality between turnover intentions and psychological contract orientations. Then, in Study 1, we tested our mediated model using a sample of employees from a large drug retailing chain. In Study 2, we expanded our model by arguing that the mediated effects are much stronger when the organization is deemed responsible for potential exit. We then tested our full model using a sample of employees from a large state-owned telecommunications corporation in China. Across both studies, results were generally consistent and supportive of our hypotheses. We discuss the implications of our findings for future theory, research, and practice regarding the management of both the turnover process and discretionary behaviors at work. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A novel method for objective vision testing in canine models of inherited retinal disease.

PubMed

Gearhart, Patricia M; Gearhart, Chris C; Petersen-Jones, Simon M

2008-08-01

The use of canine models of retinal disease in the development of therapeutic strategies for inherited retinal disorders is a growing area of research. To evaluate accurately the success of potential vision-enhancing treatments, reliable methods for objectively assessing visual function in canine models is necessary. A simple vision-testing device was constructed that consisted of a junction box with four exit tunnels. Dogs were placed in the junction box and given one vision-based choice for exit. The first-choice tunnel and time to exit were recorded and analyzed. Two canine models of retinal disease with distinct molecular defects, a null mutation in the gene encoding the alpha subunit of rod cyclic GMP phosphodiesterase (PDE6A), and a null mutation in the gene encoding a retinal pigment epithelium-specific protein (RPE65) were tested and compared to those in unaffected dogs. With the use of bright light versus dim red light, the test differentiated between unaffected dogs and dogs affected with either mutation with a high degree of certainty. The white-light intensity series showed a significantly different performance between the unaffected and affected dogs. A significant difference in performance was detected between the dogs with each mutation. The results indicate that this novel canine vision-testing method is an accurate and sensitive means of distinguishing between unaffected dogs and dogs affected with two different forms of inherited retinal disease and should be useful as a means of assessing response to therapy in future studies.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breault, Ronald W.; Monazam, Esmail R.; Shadle, Lawrence J.

Riser hydrodynamics are a function of the flow rates of gas and solids as well as the exit geometry, particularly when operated above the upper transport velocity. This work compares the exit voidage for multiple geometries and two different solids: Geldart group A glass beads and Geldart group B coke. Geometries were changed by modifying the volume of an abrupt T-shaped exit above the lateral riser exit. This was accomplished by positioning a plunger at various heights above the exit from zero to 0.38 m. A dimensionless expression used to predict smooth exit voidage was modified to account for themore » effect of the depth of the blind-T. The new correlation contains the solids-gas load ratio, solids-to-gas density ratio, bed-to-particle diameter ratio, gas Reynolds Number, as well as a term for the exit geometry. This study also found that there was a minimum riser roof height above the blind-T exit beyond which the riser exit voidage was not affected by the exit geometry. A correlation for this minimum riser roof height has also been developed in this study. This study covered riser superficial gas velocities of 4.35 to 7.7 m/s and solids circulation rates of 1.3 to 11.5 kg/s.« less

Influence of drill helical direction on exit damage development in drilling carbon fiber reinforced plastic

NASA Astrophysics Data System (ADS)

Bai, Y.; Jia, Z. Y.; Wang, F. J.; Fu, R.; Guo, H. B.; Cheng, D.; Zhang, B. Y.

2017-06-01

Drilling is inevitable for CFRP components’ assembling process in the aviation industry. The exit damage frequently occurs and affects the load carrying capacity of components. Consequently, it is of great urgency to enhance drilling exit quality on CFRP components. The article aims to guide the reasonable choice of drill helical direction and effectively reduce exit damage. Exit observation experiments are carried out with left-hand helical, right-hand helical and straight one-shot drill drilling T800S CFRP laminates separately. The development rules of exit damage and delamination factor curves are obtained. Combined with loading conditions and fracture modes of push-out burrs, and thrust force curves, the influence of drill helical direction on exit damage development is derived. It is found that the main fracture modes for left-hand helical, right-hand helical, and straight one-shot drill are mode I, extrusive fracture, mode III respectively. Among them, mode III has the least effect on exit damage development. Meanwhile, the changing rate of thrust force is relative slow for right-hand helical and straight one-shot drill in the thrust force increasing phase of stage II, which is disadvantaged for exit damage development. Therefore, straight one-shot drill’s exit quality is the best.

‘I'm So Stressed!’: A Longitudinal Model of Stress, Burnout and Engagement among Social Workers in Child Welfare Settings

PubMed Central

Travis, Dnika J.; Lizano, Erica Leeanne; Mor Barak, Michàlle E.

2016-01-01

The well-documented day-to-day and long-term experiences of job stress and burnout among employees in child welfare organisations increasingly raise concerns among leaders, policy makers and scholars. Testing a theory-driven longitudinal model, this study seeks to advance understanding of the differential impact of job stressors (work–family conflict, role conflict and role ambiguity) and burnout (emotional exhaustion and depersonalisation) on employee disengagement (work withdrawal and exit-seeking behaviours). Data were collected at three six-month intervals from an availability sample of 362 front line social workers or social work supervisors who work in a large urban public child welfare organisation in the USA. The study's results yielded a good model fit (RMSEA = 0.06, CFI = 0.96, NFI = 0.94). Work–family conflict, role ambiguity and role conflict were found to impact work withdrawal and exit-seeking behaviours indirectly through burnout. The outcome variable, exit-seeking behaviours, was positively impacted by depersonalisation and work withdrawal at a statistically significant level. Overall, findings, at least in the US context, highlight the importance of further examining the development of job burnout among social workers and social work supervisors working in child welfare settings, as well as the utility of long-term administrative strategies to mitigate risks of burnout development and support engagement. PMID:27559215

'I'm So Stressed!': A Longitudinal Model of Stress, Burnout and Engagement among Social Workers in Child Welfare Settings.

PubMed

Travis, Dnika J; Lizano, Erica Leeanne; Mor Barak, Michàlle E

2016-06-01

The well-documented day-to-day and long-term experiences of job stress and burnout among employees in child welfare organisations increasingly raise concerns among leaders, policy makers and scholars. Testing a theory-driven longitudinal model, this study seeks to advance understanding of the differential impact of job stressors (work-family conflict, role conflict and role ambiguity) and burnout (emotional exhaustion and depersonalisation) on employee disengagement (work withdrawal and exit-seeking behaviours). Data were collected at three six-month intervals from an availability sample of 362 front line social workers or social work supervisors who work in a large urban public child welfare organisation in the USA. The study's results yielded a good model fit (RMSEA = 0.06, CFI = 0.96, NFI = 0.94). Work-family conflict, role ambiguity and role conflict were found to impact work withdrawal and exit-seeking behaviours indirectly through burnout. The outcome variable, exit-seeking behaviours, was positively impacted by depersonalisation and work withdrawal at a statistically significant level. Overall, findings, at least in the US context, highlight the importance of further examining the development of job burnout among social workers and social work supervisors working in child welfare settings, as well as the utility of long-term administrative strategies to mitigate risks of burnout development and support engagement.

Thermal IR exitance model of a plant canopy

NASA Technical Reports Server (NTRS)

Kimes, D. S.; Smith, J. A.; Link, L. E.

1981-01-01

A thermal IR exitance model of a plant canopy based on a mathematical abstraction of three horizontal layers of vegetation was developed. Canopy geometry within each layer is quantitatively described by the foliage and branch orientation distributions and number density. Given this geometric information for each layer and the driving meteorological variables, a system of energy budget equations was determined and solved for average layer temperatures. These estimated layer temperatures, together with the angular distributions of radiating elements, were used to calculate the emitted thermal IR radiation as a function of view angle above the canopy. The model was applied to a lodgepole pine (Pinus contorta) canopy over a diurnal cycle. Simulated vs measured radiometric average temperatures of the midcanopy layer corresponded with 2 C. Simulation results suggested that canopy geometry can significantly influence the effective radiant temperature recorded at varying sensor view angles.

Large Eddy Simulation in a Channel with Exit Boundary Conditions

NASA Technical Reports Server (NTRS)

Cziesla, T.; Braun, H.; Biswas, G.; Mitra, N. K.

1996-01-01

The influence of the exit boundary conditions (vanishing first derivative of the velocity components and constant pressure) on the large eddy simulation of the fully developed turbulent channel flow has been investigated for equidistant and stretched grids at the channel exit. Results show that the chosen exit boundary conditions introduce some small disturbance which is mostly damped by the grid stretching. The difference between the fully developed turbulent channel flow obtained with LES with periodicity condition and the inlet and exit and the LES with fully developed flow at the inlet and the exit boundary condition is less than 10% for equidistant grids and less than 5% for the case grid stretching. The chosen boundary condition is of interest because it may be used in complex flows with backflow at exit.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reininger, Ruben; Dhesi, Sarnjeet

The main requirement of the Nanoscience Beamline at Diamond is to deliver the highest possible flux at the sample position of a PEEM with a resolving power of about 5000 in the energy range 80-2000 eV. The source of the beamline is a couple of APPLE II helical undulators in tandem that can also be used separately to allow for faster switching of the circular polarization. Based on its versatility, a collimated plane grating monochromator using sagittally focusing elements was chosen to cover the required energy range with three gratings. The operation of this monochromator requires a collimated beam incidentmore » on the grating along the dispersion direction. This can be achieved either with a toroid, focusing with its major radius along the non-dispersive direction at the exit slit, or with a sagittal cylinder. The former option uses a sagittal cylinder after the grating to focus the collimated beam at the exit slit. In the latter case, a toroid after the grating is used to focus in both directions at the exit slit. The advantage of the toroid downstream the grating is the higher horizontal demagnification. This configuration fulfills the Nanoscience Beamline's required resolving power but cannot be used to achieve very high resolution due to the astigmatic coma aberration of the toroidal mirror. The focusing at the sample position is performed with a KB pair of plane elliptical mirrors. Assuming achievable values for the errors on all the optical surfaces, the expected spots FWHW in the horizontal and vertical directions are 10 {mu}m and 3 {mu}m, respectively. The calculated photon flux at this spot at 5000 resolving power is >1012 photons/sec between 80 and 1600 eV for linearly polarized light and between 106 and 1200 eV for circularly polarized light. The beamline is expected to be operational in January 2007.« less

Working conditions as predictors of retirement intentions and exit from paid employment: a 10-year follow-up of the English Longitudinal Study of Ageing.

PubMed

Carr, Ewan; Hagger-Johnson, Gareth; Head, Jenny; Shelton, Nicola; Stafford, Mai; Stansfeld, Stephen; Zaninotto, Paola

Population ageing in Western countries has made delayed retirement and extended working life a policy priority in recent years. Retirement timing has been linked to individual factors such as health and wealth, but less is known about the role of the psychosocial work environment. This paper drew upon longitudinal data on 3462 workers aged 50-69 from five waves of the English Longitudinal Study of Ageing (ELSA). Regression models were used to assess the association of working conditions with preferred timing of retirement and actual work exit. Adjusting for a range of covariates, job demands (aspects of the job requiring sustained physical or psychological effort) were associated with preferences for earlier retirement (by 0.18 years; 95 % C.I. 0.06, 0.31). Decision authority was associated with preferences for later retirement (by 0.38 years; 95 % C.I. 0.23, 0.53) and reduced odds of work exit (OR = 0.93; 95 % C.I. 0.88, 0.97). Low recognition at work was associated with increased odds of work exit (OR = 1.23; 95 % C.I. 1.10, 1.43). There was little evidence of any interactive relationship between demands and resources. Efforts to extend working life should address issues relating to the immediate psychosocial work environment. Providing older workers with increased sense of control, and ensuring contributions are adequately recognised, may delay retirement intentions and the timing of labour market exit.

A driving simulator study of driver performance on deceleration lanes.

PubMed

Calvi, A; Benedetto, A; De Blasiis, M R

2012-03-01

Deceleration lanes are important because they help drivers transition from high-speed lanes to low-speed ramps. Although they are designed to allow vehicles to depart the freeway safely and efficiently, many studies report high accident rates on exit ramps with the highest percentage of crashes taking place in deceleration lanes. This paper describes the results of a driving simulator study that focused on driving performance while approaching a divergence area and decelerating during the exiting maneuver. Three different traffic scenarios were simulated to analyze the influence of traffic volume on driving performance. Thirty drivers drove in the simulator in these scenarios while data on their lateral position, speed and deceleration were collected. Our results indicate there are considerable differences between the main assumptions of models generally used to design deceleration lanes and actual driving performance. In particular, diverging drivers begin to decelerate before arriving at the deceleration lane, causing interference with the main flow. Moreover, speeds recorded at the end of the deceleration lane exceed those for which the ramp's curves are designed; this creates risky driving conditions that could explain the high crash rates found in studies of exit ramps. Finally, statistical analyses demonstrate significant influences of traffic volume on some aspects of exiting drivers' performance: lower traffic volume results in elevated exiting speed and deceleration, and diverging drivers begin to decelerate earlier along the main lane when traffic volume is low. However, speeds at the end of the deceleration lane and the site of lane changing are not significantly influenced by traffic volume. Copyright © 2011 Elsevier Ltd. All rights reserved.

Noise produced by the large-scale transition region structure of turbulent jets

NASA Technical Reports Server (NTRS)

Hardin, J. C.

1974-01-01

The 'orderly' structure which has been observed recently by numerous researchers within the transition region of subsonic turbulent jets is analyzed to reveal its noise-producing potential. For the case of a circular jet, this structure is modeled as a train of toroidal vortex rings which are formed near the jet exit and propagate downstream. The noise produced by the model is evaluated from a reformulation of Lighthill's expression for the far-field acoustic density which emphasizes the importance of the vorticity within the turbulent flow field. It is shown that the noise production occurs mainly close to the jet exit and depends primarily upon temporal changes in the toroidal radii. These results suggest a new approach to noise suppression which has been substantiated experimentally.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mazuritskiy, M. I., E-mail: mazurmik@gmail.com; Lerer, A. M.; Makhno, P. V.

The angular distribution of the X-ray intensity at the exit of microchannel plates at grazing incidence of monochromatic radiation on the walls of microcapillaries has been investigated. The angles and energies of the primary radiation quanta at which the synchrotron beam excites X-ray fluorescence propagating inside polycapillary structures have been determined. The angular dependences of the intensity distribution of X-rays transmitted through the microcapillaries have been studied theoretically and experimentally for energies corresponding to the region of anomalous dispersion near the L{sub 2,3} absorption edges of silicon. The propagation of waves in hollow polycapillary waveguides, the excitation of X-ray fluorescence,more » and the X-ray diffraction at the exit of microchannel plates have been modeled mathematically. The mathematical model takes into account the presence of a transition layer on the microchannel surface.« less

The temporal evolution of pyroclast ejection velocity and exit trajectory, a laboratory case study.

NASA Astrophysics Data System (ADS)

Cigala, Valeria; Kueppers, Ulrich; José Peña Fernández, Juan; Sesterhenn, Jörn; Taddeucci, Jacopo; Dingwell, Donald Bruce

2017-04-01

Pyroclast ejection dynamics during explosive volcanic eruptions are highly variable. This variability is due to complex interaction among different parameters, which define the boundary conditions for a certain eruption. Scaled and controlled laboratory experiments come in hand to characterize the effect of specific physical parameters on the ejection dynamics. We focus, in particular, on the dynamics of pyroclasts ejection in the region just above the vent, also called gas-thrust region, for the case of impulsively released gas-pyroclast mixtures (i.e., unsteady eruptions). In this study, gas-particle mixtures were released in a series of shock-tube experiments with varying 1) tube length, 2) vent geometry, 3) gas-particle ratio, 4) initial temperature and 5) particle size distribution. The tube length was varied by changing the starting sample load, resulting in a gas-particle ratio of 1, 2.5 and 8, respectively. Thereby, the initial distance of the sample from the exit varied between 320, 230 and 140 mm, respectively, allowing for variable time for accelerating (and possibly decelerating) the particles prior to exit. Moreover, four vent geometries were employed, a nozzle with converging walls (5°), a cylinder and two funnels with walls diverging at 15° and 30° respectively. All of them are characterized by a value h/D=1.07, where h is the length between the throat and the lip of the vent and D is throat diameter. The experiments were performed at both 500°C and room temperature using particles from 2 to 0.125 mm in diameter. In all experiments, initial pressure was 15 MPa. High speed videos of the ejection behaviour were analyzed to obtain the temporal evolution of particle velocity and exit trajectory depending on boundary conditions. Max velocity of 300 m/s was observed together with a non-linear decay of exit velocity over time. The exit trajectories were found to deviate from the vertical by 5° to 45° and also display a non-linear evolution with time. Moreover, the velocity decay was used to investigate the accuracy of the empirical fragmentation depth model from Alatorre-Ibargüengoitia et al. (2011), when different gas-particle ratios are employed. This model is not reproducing all experimental constellations satisfactorily. Further experiments will help to develop this model further. Vent geometry, particle size and temperature show the largest effect on ejection velocity and trajectory. In particular, we observed a positive correlation of velocity with 1) diverging vent walls and 2) temperature and a negative correlation with 1) starting tube length and 2) particle size. On the other hand, exit trajectories show negative correlation with 1) diverging walls, 2) starting tube length, 3) temperature and 4) particle size. Moreover, we found that gas-particle ratio additionally strongly affects the temporal evolution of particle ejection velocity and trajectory. These results highlight the importance of scaled and repeatable laboratory experiments for an enhanced understanding of natural volcanic phenomena that bear direct observability. A closer link will enhance volcanic hazard assessment.

Aircraft evacuations through type-III exits I : effects of seat placement at the exit.

DOT National Transportation Integrated Search

1995-07-01

Simulated emergency egress from Type III over-wing exits was studied to support regulatory action by the FAA. Passageway width and seat encroachment distance adjacent to the Type-III exit were the major variables of interest. : Methods. Two subject g...

29 CFR 1910.36 - Design and construction requirements for exit routes.

Code of Federal Regulations, 2012 CFR

2012-07-01

....36 Section 1910.36 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Exit Routes and Emergency Planning... of exit routes necessary for your workplace, consult NFPA 101-2000, Life Safety Code. (c) Exit...

Safety and operational performance evaluation of four types of exit ramps on Florida's freeways (final report).

DOT National Transportation Integrated Search

2010-12-01

This project mainly focuses on exit ramp performance analysis of safety and operations. In addition, issues of advance guide sign for exit ramp are also mentioned. : Safety analysis evaluates safety performances of different exit ramps used in Florid...

The ground vortex flow field associated with a jet in a cross flow impinging on a ground plane for uniform and annular turbulent axisymmetric jets. M.S. Thesis

NASA Technical Reports Server (NTRS)

Cavage, William M.; Kuhlman, John M.

1993-01-01

An experimental study was conducted of the impingement of a single circular jet on a ground plane in a cross flow. This geometry is a simplified model of the interaction of propulsive jet exhaust from a V/STOL aircraft with the ground in forward flight. Jets were oriented normal to the cross flow and ground plane. Jet size, cross flow-to-jet velocity ratio, ground plane-to-jet board spacing, and jet exit turbulence level and mean velocity profile shape were all varied to determine their effects on the size of the ground vortex interaction region which forms on the ground plane, using smoke injection into the jet. Three component laser Doppler velocimeter measurements were made with a commercial three color system for the case of a uniform jet with exit spacing equal to 5.5 diameters and cross flow-to-jet velocity ratio equal to 0.11. The flow visualization data compared well for equivalent runs of the same nondimensional jet exit spacing and the same velocity ratio for different diameter nozzles, except at very low velocity ratios and for the larger nozzle, where tunnel blockage became significant. Variation of observed ground vortex size with cross flow-to-jet velocity ratio was consistent with previous studies. Observed effects of jet size and ground plane-to-jet board spacing were relatively small. Jet exit turbulence level effects were also small. However, an annular jet with a low velocity central core was found to have a significantly smaller ground vortex than an equivalent uniform jet at the same values of cross flow-to-jet velocity ratio and jet exit-to-ground plane spacing. This may suggest a means of altering ground vortex behavior somewhat, and points out the importance of proper simulation of jet exit velocity conditions. LV data indicated unsteady turbulence levels in the ground vortex in excess of 70 percent.

The health of HIV-exposed children after early weaning.

PubMed

Parker, Megan E; Tembo, Martin; Adair, Linda; Chasela, Charles; Piwoz, Ellen G; Jamieson, Denise J; Ellington, Sascha; Kayira, Dumbani; Soko, Alice; Mkhomawanthu, Chimwemwe; Martinson, Francis; van der Horst, Charles M; Bentley, Margaret E

2013-04-01

There are potential health risks associated with the use of early weaning to prevent mother-to-child transmission of human immunodeficiency virus (HIV) in resource-poor settings. Our objective was to examine growth and nutrient inadequacies among a cohort of children weaned early. Children participating in the Breastfeeding Antiretrovirals and Nutrition (BAN) Study in Lilongwe, Malawi, had HIV-infected mothers, were weaned at 6 months and fed LNS until 12 months. 40 HIV-negative, BAN-exited children were compared with 40 HIV-negative, community children matched on age, gender and local health clinic. Nutrient intake was calculated from 24-h dietary recalls collected from BAN-exited children. Anthropometric measurements were collected from BAN-exited and matched community children at 15-16 months, and 2 months later. Longitudinal random effects sex-stratified models were used to evaluate anthropometric differences between the two groups. BAN-exited children consumed adequate energy, protein and carbohydrates but inadequate amounts of fat. The prevalence of inadequate micronutrient intakes were: 46% for vitamin A; 20% for vitamin B6; 69% for folate; 13% for vitamin C; 19% for iron; 23% for zinc. Regarding growth, BAN-exited girls gained weight at a significantly lower rate {0.02 g kg(-1) per day [95% confidence interval (CI): 0.01, 0.03]} than their matched comparison [0.05 g kg(-1) per day (95% CI: 0.03, 0.07)]; BAN girls grew significantly slower [0.73 cm month(-1) (95% CI: 0.40,1.06)] than their matched comparison (1.55 cm month(-1) [95% CI: 0.98, 2.12]). Among this sample of BAN-exited children, early weaning was associated with dietary deficiencies and girls experienced reduced growth velocity. In resource-poor settings, HIV prevention programmes must ensure that breastfeeding stop only once a nutritionally adequate and safe diet without breast milk can be provided. © 2011 Blackwell Publishing Ltd.

Process for Considering Special Exit Criteria from Bilingual/English as a Second Language (ESL) Services under 19 TAC §89.1225(k). School Year: 2013-2014, Grades 1-12

ERIC Educational Resources Information Center

Texas Education Agency, 2014

2014-01-01

Under Texas Administrative Code (TAC) §89.1225(h), districts are required to use the exit criteria represented in the chart titled "2013-2014 English Proficiency Exit Criteria Chart" found at (http://www.tea.state.tx.us/index2.aspx?id=4098) to exit English language learners (ELLs) from bilingual/ESL programs. The exit criteria under TAC…

The effect of riser end geometry on gas-solid hydrodynamics in a CFB riser operating in the core annular and dilute homogeneous flow regimes

DOE PAGES

Breault, Ronald W.; Monazam, Esmail R.; Shadle, Lawrence J.; ...

2017-02-12

Riser hydrodynamics are a function of the flow rates of gas and solids as well as the exit geometry, particularly when operated above the upper transport velocity. This work compares the exit voidage for multiple geometries and two different solids: Geldart group A glass beads and Geldart group B coke. Geometries were changed by modifying the volume of an abrupt T-shaped exit above the lateral riser exit. This was accomplished by positioning a plunger at various heights above the exit from zero to 0.38 m. A dimensionless expression used to predict smooth exit voidage was modified to account for themore » effect of the depth of the blind-T. The new correlation contains the solids-gas load ratio, solids-to-gas density ratio, bed-to-particle diameter ratio, gas Reynolds Number, as well as a term for the exit geometry. This study also found that there was a minimum riser roof height above the blind-T exit beyond which the riser exit voidage was not affected by the exit geometry. A correlation for this minimum riser roof height has also been developed in this study. This study covered riser superficial gas velocities of 4.35 to 7.7 m/s and solids circulation rates of 1.3 to 11.5 kg/s.« less

Plume-exit modeling to determine cloud condensation nuclei activity of aerosols from residential biofuel combustion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mena, Francisco; Bond, Tami C.; Riemer, Nicole

Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty in the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics (coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume from emission until plume exit, defined here as the condition when the plume reaches ambient temperature and specific humidity through entrainment. We found that aerosol-scale dynamics affect CCNmore » activity only during the first few seconds of evolution, after which the CCN efficiency reaches a constant value. Homogenizing factors in a plume are co-emission of semi-volatile organic compounds (SVOCs) or emission at small particle sizes; SVOC co-emission can be the main factor determining plume-exit CCN for hydrophobic or small particles. Coagulation limits emission of CCN to about 10 16 per kilogram of fuel. Depending on emission factor, particle size, and composition, some of these particles may not activate at low supersaturation ( s sat). Hygroscopic Aitken-mode particles can contribute to CCN through self-coagulation but have a small effect on the CCN activity of accumulation-mode particles, regardless of composition differences. Simple models (monodisperse coagulation and average hygroscopicity) can be used to estimate plume-exit CCN within about 20 % if particles are unimodal and have homogeneous composition, or when particles are emitted in the Aitken mode even if they are not homogeneous. On the other hand, if externally mixed particles are emitted in the accumulation mode without SVOCs, an average hygroscopicity overestimates emitted CCN by up to a factor of 2. This work has identified conditions under which particle populations become more homogeneous during plume processes. This homogenizing effect requires the components to be truly co-emitted, rather than sequentially emitted.« less

Plume-exit modeling to determine cloud condensation nuclei activity of aerosols from residential biofuel combustion

NASA Astrophysics Data System (ADS)

Mena, Francisco; Bond, Tami C.; Riemer, Nicole

2017-08-01

Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty in the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics (coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume from emission until plume exit, defined here as the condition when the plume reaches ambient temperature and specific humidity through entrainment. We found that aerosol-scale dynamics affect CCN activity only during the first few seconds of evolution, after which the CCN efficiency reaches a constant value. Homogenizing factors in a plume are co-emission of semi-volatile organic compounds (SVOCs) or emission at small particle sizes; SVOC co-emission can be the main factor determining plume-exit CCN for hydrophobic or small particles. Coagulation limits emission of CCN to about 1016 per kilogram of fuel. Depending on emission factor, particle size, and composition, some of these particles may not activate at low supersaturation (ssat). Hygroscopic Aitken-mode particles can contribute to CCN through self-coagulation but have a small effect on the CCN activity of accumulation-mode particles, regardless of composition differences. Simple models (monodisperse coagulation and average hygroscopicity) can be used to estimate plume-exit CCN within about 20 % if particles are unimodal and have homogeneous composition, or when particles are emitted in the Aitken mode even if they are not homogeneous. On the other hand, if externally mixed particles are emitted in the accumulation mode without SVOCs, an average hygroscopicity overestimates emitted CCN by up to a factor of 2. This work has identified conditions under which particle populations become more homogeneous during plume processes. This homogenizing effect requires the components to be truly co-emitted, rather than sequentially emitted.

Plume-exit modeling to determine cloud condensation nuclei activity of aerosols from residential biofuel combustion

DOE PAGES

Mena, Francisco; Bond, Tami C.; Riemer, Nicole

2017-08-07

Residential biofuel combustion is an important source of aerosols and gases in the atmosphere. The change in cloud characteristics due to biofuel burning aerosols is uncertain, in part, due to the uncertainty in the added number of cloud condensation nuclei (CCN) from biofuel burning. We provide estimates of the CCN activity of biofuel burning aerosols by explicitly modeling plume dynamics (coagulation, condensation, chemical reactions, and dilution) in a young biofuel burning plume from emission until plume exit, defined here as the condition when the plume reaches ambient temperature and specific humidity through entrainment. We found that aerosol-scale dynamics affect CCNmore » activity only during the first few seconds of evolution, after which the CCN efficiency reaches a constant value. Homogenizing factors in a plume are co-emission of semi-volatile organic compounds (SVOCs) or emission at small particle sizes; SVOC co-emission can be the main factor determining plume-exit CCN for hydrophobic or small particles. Coagulation limits emission of CCN to about 10 16 per kilogram of fuel. Depending on emission factor, particle size, and composition, some of these particles may not activate at low supersaturation ( s sat). Hygroscopic Aitken-mode particles can contribute to CCN through self-coagulation but have a small effect on the CCN activity of accumulation-mode particles, regardless of composition differences. Simple models (monodisperse coagulation and average hygroscopicity) can be used to estimate plume-exit CCN within about 20 % if particles are unimodal and have homogeneous composition, or when particles are emitted in the Aitken mode even if they are not homogeneous. On the other hand, if externally mixed particles are emitted in the accumulation mode without SVOCs, an average hygroscopicity overestimates emitted CCN by up to a factor of 2. This work has identified conditions under which particle populations become more homogeneous during plume processes. This homogenizing effect requires the components to be truly co-emitted, rather than sequentially emitted.« less

A Conceptual Framework for Predicting the Toxicity of Reactive Chemicals: Modeling Soft Electrophilicity

EPA Science Inventory

Although the literature is replete with QSAR models developed for many toxic effects caused by reversible chemical interactions, the development of QSARs for the toxic effects of reactive chemicals lacks a consistent approach. While limitations exit, an appropriate starting-point...

Experimental and numerical investigation of ram extrusion of bread dough

NASA Astrophysics Data System (ADS)

Mohammed, M. A. P.; Wanigasooriya, L.; Charalambides, M. N.

2016-10-01

An experimental and numerical study on ram extrusion of bread dough was conducted. A laboratory ram extrusion rig was designed and manufactured, where dies with different angles and exit radii were employed. Rate dependent behaviour was observed from tests conducted at different extrusion speeds, and higher extrusion pressure was reported for dies with decreasing exit radius. A finite element simulation of extrusion was performed using the adaptive meshing technique in Abaqus. Simulations using a frictionless contact between the billet and die wall showed that the model underestimates the response at high entry angles. On the other hand, when the coefficient of friction value was set to 0.09 as measured from friction experiments, the dough response was overestimated, i.e. the model extrusion pressure was much higher than the experimentally measured values. When a critical shear stress limit, τmax, was used, the accuracy of the model predictions improved. The results showed that higher die angles require higher τmax values for the model and the experiments to agree.

Effect of an offshore sinkhole perforation in a coastal confined aquifer on submarine groundwater discharge

USGS Publications Warehouse

Fratesi, S.E.; Leonard, V.; Sanford, W.E.

2007-01-01

In order to explore submarine groundwater discharge in the vicinity of karst features that penetrate the confining layer of an offshore, partially confined aquifer, we constructed a three-dimensional groundwater model using the SUTRA (Saturated-Unsaturated TRAnsport) variable-density groundwater flow model. We ran a parameter sensitivity analysis, testing the effects of recharge rates, permeabilities of the aquifer and confining layer, and thickness of the confining layer. In all simulations, less than 20% of the freshwater recharge for the entire model exits through the sinkhole. Recirculated seawater usually accounts for 10-30% of the total outflow from the model. Often, the sinkhole lies seaward of the transition zone and acts as a recharge feature for recirculating seawater. The permeability ratio between aquifer and confining layer influences the configuration of the freshwater wedge the most; as confining layer permeability decreases, the wedge lengthens and the fraction of total discharge exiting through the sinkhole increases. Copyright ?? 2007 IAHS Press.

Factors Associated With Premature Exits From Supported Housing.

PubMed

Gabrielian, Sonya; Burns, Alaina V; Nanda, Nupur; Hellemann, Gerhard; Kane, Vincent; Young, Alexander S

2016-01-01

Many homeless consumers who enroll in supported housing programs--which offer subsidized housing and supportive services--disengage prematurely, before placement in permanent community-based housing. This study explored factors associated with exiting a supported housing program before achieving housing placement. With the use of administrative data, a roster was obtained for consumers enrolled in the Veterans Affairs (VA) Greater Los Angeles supported housing program from 2011 to 2012. Fewer (4%) consumers exited this program before achieving housing ("exiters") compared with consumers described in national VA figures (18%). Exiters with available demographic data (N=51) were matched 1:1 on age, gender, marital status, and race-ethnicity with consumers housed through this program ("stayers," N=51). Medical records were reviewed to compare diagnoses, health care utilization, housing histories, vocational history, and criminal justice involvement of exiters versus stayers. Exiters' housing outcomes were identified. Recursive partitioning identified variables that best differentiated exiters from stayers. Several factors were associated with premature exits from this supported housing program: residing in temporary housing on hospital grounds during program enrollment, poor adherence to outpatient care, substance use disorders, hepatitis C, chronic pain, justice involvement, frequent emergency department utilization, and medical-surgical admissions. The first of these factors and poor adherence to outpatient medical-surgical care best differentiated exiters from stayers. Moreover, >50% of exiters became street homeless or incarcerated after leaving the program. In that diverse social factors, diagnoses, and health care utilization patterns were associated with premature disengagement from supported housing, future research is needed to implement and evaluate rehabilitative services that address these factors, adapted to the context of supported housing.

34 CFR 682.604 - Required exit counseling for borrowers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 34 Education 4 2014-07-01 2014-07-01 false Required exit counseling for borrowers. 682.604 Section... counseling for borrowers. (a) Exit counseling. (1) A school must ensure that exit counseling is conducted... ensure that this counseling is conducted shortly before the student borrower ceases at least half-time...

14 CFR 27.1557 - Miscellaneous markings and placards.

Code of Federal Regulations, 2011 CFR

2011-01-01

...; (iii) For turbine engine powered rotorcraft, the permissible fuel designations; and (iv) For pressure...) Emergency exit placards. Each placard and operating control for each emergency exit must be red. A placard must be near each emergency exit control and must clearly indicate the location of that exit and its...

14 CFR 27.1557 - Miscellaneous markings and placards.

Code of Federal Regulations, 2013 CFR

2013-01-01

...; (iii) For turbine engine powered rotorcraft, the permissible fuel designations; and (iv) For pressure...) Emergency exit placards. Each placard and operating control for each emergency exit must be red. A placard must be near each emergency exit control and must clearly indicate the location of that exit and its...

14 CFR 27.1557 - Miscellaneous markings and placards.

Code of Federal Regulations, 2012 CFR

2012-01-01

...; (iii) For turbine engine powered rotorcraft, the permissible fuel designations; and (iv) For pressure...) Emergency exit placards. Each placard and operating control for each emergency exit must be red. A placard must be near each emergency exit control and must clearly indicate the location of that exit and its...

14 CFR 27.1557 - Miscellaneous markings and placards.

Code of Federal Regulations, 2014 CFR

2014-01-01

...; (iii) For turbine engine powered rotorcraft, the permissible fuel designations; and (iv) For pressure...) Emergency exit placards. Each placard and operating control for each emergency exit must be red. A placard must be near each emergency exit control and must clearly indicate the location of that exit and its...

36 CFR 13.1318 - Location of the EGDA.

Code of Federal Regulations, 2013 CFR

2013-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed... boundary to Exit Glacier Campground Entrance Road, all park areas within 350 meters (383 yards) of the centerline of the Exit Glacier Road; (2) From Exit Glacier Campground Entrance Road to the end of the main...

36 CFR 13.1318 - Location of the EGDA.

Code of Federal Regulations, 2011 CFR

2011-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed... boundary to Exit Glacier Campground Entrance Road, all park areas within 350 meters (383 yards) of the centerline of the Exit Glacier Road; (2) From Exit Glacier Campground Entrance Road to the end of the main...

36 CFR 13.1318 - Location of the EGDA.

Code of Federal Regulations, 2014 CFR

2014-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed... boundary to Exit Glacier Campground Entrance Road, all park areas within 350 meters (383 yards) of the centerline of the Exit Glacier Road; (2) From Exit Glacier Campground Entrance Road to the end of the main...

Precursor systems analyses of automated highway systems. Activity area p preliminary cost/benefit factors analysis. Volume 4. Roadway costs. Final report, September 1993-November 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1995-06-01

This report gives a preliminary cost benefit factor analysis for Automatic Highway Systems (AHS) implementation on a representative section of existing highway. The text describes the approach used to develop cost associated with the roadway portion of AHS and gives cost estimates for 5 basic implementation options: install `transparent equipment in roadway` that will give performance gains to those vehicles equipped to `see` it (e.g. magnetic nails); move towards separated roadway for AHS rumble strips or paint, then fully separated with either continuous barriers with dedicated entry/exit ramps or separate facility such an elevated structure; expand AHS capabilities further somore » AHS traffic can now use existing roadways with other traffic and formerly dedicated facilities can be converted to higher speed through traffic. However, the actual implementation will necessarily be a function of local roadway geometry, system demand, and a complex combination of other factors. Very few existing roadways can accommodate these specific conversions directly. Therefore, we have generated roadway retrofit options that can be used depending on local geometry to support this general evolution philosophy.« less

Analytical expression for the exit probability of the q -voter model in one dimension

NASA Astrophysics Data System (ADS)

Timpanaro, André M.; Galam, Serge

2015-07-01

We present in this paper an approximation that is able to give an analytical expression for the exit probability of the q -voter model in one dimension. This expression gives a better fit for the more recent data about simulations in large networks [A. M. Timpanaro and C. P. C. do Prado, Phys. Rev. E 89, 052808 (2014), 10.1103/PhysRevE.89.052808] and as such departs from the expression ρ/qρq+(1-ρ ) q found in papers that investigated small networks only [R. Lambiotte and S. Redner, Europhys. Lett. 82, 18007 (2008), 10.1209/0295-5075/82/18007; P. Przybyła et al., Phys. Rev. E 84, 031117 (2011), 10.1103/PhysRevE.84.031117; F. Slanina et al., Europhys. Lett. 82, 18006 (2008), 10.1209/0295-5075/82/18006]. The approximation consists in assuming a large separation on the time scales at which active groups of agents convince inactive ones and the time taken in the competition between active groups. Some interesting findings are that for q =2 we still have ρ/2ρ2+(1-ρ ) 2 as the exit probability and for q >2 we can obtain a lower-order approximation of the form ρ/sρs+(1-ρ ) s with s varying from q for low values of q to q -1/2 for large values of q . As such, this work can also be seen as a deduction for why the exit probability ρ/qρq+(1-ρ ) q gives a good fit, without relying on mean-field arguments or on the assumption that only the first step is nondeterministic, as q and q -1/2 will give very similar results when q →∞ .

Variable Sampling Mapping

NASA Technical Reports Server (NTRS)

Smith, Jeffrey, S.; Aronstein, David L.; Dean, Bruce H.; Lyon, Richard G.

2012-01-01

The performance of an optical system (for example, a telescope) is limited by the misalignments and manufacturing imperfections of the optical elements in the system. The impact of these misalignments and imperfections can be quantified by the phase variations imparted on light traveling through the system. Phase retrieval is a methodology for determining these variations. Phase retrieval uses images taken with the optical system and using a light source of known shape and characteristics. Unlike interferometric methods, which require an optical reference for comparison, and unlike Shack-Hartmann wavefront sensors that require special optical hardware at the optical system's exit pupil, phase retrieval is an in situ, image-based method for determining the phase variations of light at the system s exit pupil. Phase retrieval can be used both as an optical metrology tool (during fabrication of optical surfaces and assembly of optical systems) and as a sensor used in active, closed-loop control of an optical system, to optimize performance. One class of phase-retrieval algorithms is the iterative transform algorithm (ITA). ITAs estimate the phase variations by iteratively enforcing known constraints in the exit pupil and at the detector, determined from modeled or measured data. The Variable Sampling Mapping (VSM) technique is a new method for enforcing these constraints in ITAs. VSM is an open framework for addressing a wide range of issues that have previously been considered detrimental to high-accuracy phase retrieval, including undersampled images, broadband illumination, images taken at or near best focus, chromatic aberrations, jitter or vibration of the optical system or detector, and dead or noisy detector pixels. The VSM is a model-to-data mapping procedure. In VSM, fully sampled electric fields at multiple wavelengths are modeled inside the phase-retrieval algorithm, and then these fields are mapped to intensities on the light detector, using the properties of the detector and optical system, for comparison with measured data. Ultimately, this model-to-data mapping procedure enables a more robust and accurate way of incorporating the exit-pupil and image detector constraints, which are fundamental to the general class of ITA phase retrieval algorithms.

Measurement of atmospheric pressure microplasma jet with Langmuir probes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Kunning G., E-mail: gabe.xu@uah.edu; Doyle, Steven J.

2016-09-15

A radio frequency argon microplasma jet at atmospheric-pressure is characterized using Langmuir probes. While optical methods are the typical diagnostic for these small scale plasmas, the simplicity and low cost of Langmuir probes makes them an attractive option. The plasma density and electron temperature are measured using existing high-pressure Langmuir probe theories developed for flames and arcs. The density and temperature vary from 1 × 10{sup 16} to 1 × 10{sup 19} m{sup −3} and 2.3 to 4.4 eV, respectively, depending on the operating condition. The density decreases while the electron temperature increases with axial distance from the jet exit. Themore » applicability of the probe theories as well as the effect of collisionality and jet mixing is discussed.« less

The importance of employment status in determining exit rates from nursing.

PubMed

Daniels, Frieda; Laporte, Audrey; Lemieux-Charles, Louise; Baumann, Andrea; Onate, Kanecy; Deber, Raisa

2012-01-01

To mitigate nurse shortages, health care decision makers tend to employ retention strategies that assume nurses employed in full-time, part-time, or casual positions and working in different sectors have similar preferences for work. However, this assumption has not been validated in the literature. The relationship between a nurse's propensity to exit the nurse profession in Ontario and employment status was explored by building an extended Cox Proportional Hazards Regression Model using a counting process technique. The differential exit patterns between part-time and casual nurses suggest that the common practice of treating part-time and casual nurses as equivalent is misleading. Health care decision makers should consider nurse retention strategies specifically targeting casual nurses because this segment of the profession is at the greatest risk of leaving. Nurse executives and nurse managers should investigate the different work preferences of part-time and casual nurses to devise tailored rather than "one-size fits all" nurse retention strategies to retain casual nurses.

Scaling laws in granular flow and pedestrian flow

NASA Astrophysics Data System (ADS)

Chen, Shumiao; Alonso-Marroquin, Fernando; Busch, Jonathan; Hidalgo, Raúl Cruz; Sathianandan, Charmila; Ramírez-Gómez, Álvaro; Mora, Peter

2013-06-01

We use particle-based simulations to examine the flow of particles through an exit. Simulations involve both gravity-driven particles (representing granular material) and velocity-driven particles (mimicking pedestrian dynamics). Contact forces between particles include elastic, viscous, and frictional forces; and simulations use bunker geometry. Power laws are observed in the relation between flow rate and exit width. Simulations of granular flow showed that the power law has little dependence on the coefficient of friction. Polydisperse granular systems produced higher flow rates than those produced by monodisperse ones. We extend the particle model to include the main features of pedestrian dynamics: thoracic shape, shoulder rotation, and desired velocity oriented towards the exit. Higher desired velocity resulted in higher flow rate. Granular simulations always give higher flow rate than pedestrian simulations, despite the values of aspect ratio of the particles. In terms of force distribution, pedestrians and granulates share similar properties with the non-democratic distribution of forces that poses high risks of injuries in a bottleneck situation.

Effects of the magnetic field gradient on the wall power deposition of Hall thrusters

NASA Astrophysics Data System (ADS)

Ding, Yongjie; Li, Peng; Zhang, Xu; Wei, Liqiu; Sun, Hezhi; Peng, Wuji; Yu, Daren

2017-04-01

The effect of the magnetic field gradient in the discharge channel of a Hall thruster on the ionization of the neutral gas and power deposition on the wall is studied through adopting the 2D-3V particle-in-cell (PIC) and Monte Carlo collisions (MCC) model. The research shows that by gradually increasing the magnetic field gradient while keeping the maximum magnetic intensity at the channel exit and the anode position unchanged, the ionization region moves towards the channel exit and then a second ionization region appears near the anode region. Meanwhile, power deposition on the walls decreases initially and then increases. To avoid power deposition on the walls produced by electrons and ions which are ionized in the second ionization region, the anode position is moved towards the channel exit as the magnetic field gradient is increased; when the anode position remains at the zero magnetic field position, power deposition on the walls decreases, which can effectively reduce the temperature and thermal load of the discharge channel.

Use of exit examinations: a criterion for graduation?

PubMed

Cullen, P D

1997-01-01

This study sought to measure the use of exit examinations in nursing schools at Historically Black Colleges and Universities (HBCU). Fifteen participants from HBCU nursing schools throughout the United States were surveyed to determine current practices related to exit exams. Overall, fourteen schools (93.33%) used an exit exam at the end of their nursing program. However, 73.33% of the participants (11 schools) reported it was mandatory for students to pass the exam as a requirement for graduation. Almost 47% of the participants (7 schools) reported the use of the exit exam was related to NCLEX-RN pass rates, while others reported identification of student needs as the primary reason for using an exit exam. Most participants were very helpful by sharing their innovations. While this small study provided some information on the use of exit examinations, more research is needed to substantiate both the appropriateness and usefulness of their use in baccalaureate degree nursing programs.

46 CFR 185.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Escape hatches and emergency exits. 185.606 Section 185... 100 GROSS TONS) OPERATIONS Markings Required § 185.606 Escape hatches and emergency exits. All escape hatches and other emergency exits used as means of escape must be marked on both sides in clearly legible...

46 CFR 169.745 - Escape hatches and emergency exits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Escape hatches and emergency exits. 169.745 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.745 Escape hatches and emergency exits. Each escape hatch and other emergency exit must be marked on both sides using at least 1...

46 CFR 185.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Escape hatches and emergency exits. 185.606 Section 185... 100 GROSS TONS) OPERATIONS Markings Required § 185.606 Escape hatches and emergency exits. All escape hatches and other emergency exits used as means of escape must be marked on both sides in clearly legible...

46 CFR 169.745 - Escape hatches and emergency exits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Escape hatches and emergency exits. 169.745 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.745 Escape hatches and emergency exits. Each escape hatch and other emergency exit must be marked on both sides using at least 1...

46 CFR 185.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Escape hatches and emergency exits. 185.606 Section 185... 100 GROSS TONS) OPERATIONS Markings Required § 185.606 Escape hatches and emergency exits. All escape hatches and other emergency exits used as means of escape must be marked on both sides in clearly legible...

46 CFR 185.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Escape hatches and emergency exits. 185.606 Section 185... 100 GROSS TONS) OPERATIONS Markings Required § 185.606 Escape hatches and emergency exits. All escape hatches and other emergency exits used as means of escape must be marked on both sides in clearly legible...

46 CFR 169.745 - Escape hatches and emergency exits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Escape hatches and emergency exits. 169.745 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.745 Escape hatches and emergency exits. Each escape hatch and other emergency exit must be marked on both sides using at least 1...

46 CFR 169.745 - Escape hatches and emergency exits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Escape hatches and emergency exits. 169.745 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.745 Escape hatches and emergency exits. Each escape hatch and other emergency exit must be marked on both sides using at least 1...

46 CFR 169.745 - Escape hatches and emergency exits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Escape hatches and emergency exits. 169.745 Section 169... VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.745 Escape hatches and emergency exits. Each escape hatch and other emergency exit must be marked on both sides using at least 1...

46 CFR 185.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Escape hatches and emergency exits. 185.606 Section 185... 100 GROSS TONS) OPERATIONS Markings Required § 185.606 Escape hatches and emergency exits. All escape hatches and other emergency exits used as means of escape must be marked on both sides in clearly legible...

An Entrance to Exit Polling: Strategies for Using Exit Polls as Experiential Learning Projects

ERIC Educational Resources Information Center

Berry, Michael J.; Robinson, Tony

2012-01-01

Engaging students in the design, administration, and postelection analysis of an exit poll can be an excellent experiential learning activity. Lelieveldt and Rossen (2009) argue that exit polls are a "perfect teaching tool" because they provide students with a cooperative (rather than competitive) learning experience; help students…

40 CFR 63.3176 - What definitions apply to this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... automobiles or light-duty trucks, including coating facilities and processes. Bake oven air seal means an entry or entry vestibule to or an exit or exit vestibule from a bake oven which isolates the bake oven... exit or exit vestibule) the bake oven. No significant VOC generating activity takes place in a bake...

Exit Cards: Creating a Dialogue for Continuous Evaluation

ERIC Educational Resources Information Center

Patka, Mazna; Wallin-Ruschman, Jennifer; Wallace, Tenille; Robbins, Candice

2016-01-01

This study explored the use of Exit Cards, which are formative evaluations of student knowledge and instruction undertaken at every class meeting. Its results are based on Exit Card data from two undergraduate research methods courses. Thematic analysis indicated that students used Exit Cards to communicate (1) what they learned, (2) challenges…

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

8 CFR 215.9 - Temporary Worker Visa Exit Program.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Temporary Worker Visa Exit Program. 215.9... ALIENS DEPARTING FROM THE UNITED STATES § 215.9 Temporary Worker Visa Exit Program. An alien admitted on certain temporary worker visas at a port of entry participating in the Temporary Worker Visa Exit Program...

Exit Exam as Academic Performance Indicator

ERIC Educational Resources Information Center

Al Ahmad, Mahmoud; Al Marzouqi, Ali H.; Hussien, Mousa

2014-01-01

This paper focuses on the impact of exit exams on different elements of the educational process, namely: curriculum development, students and instructors. A 50-question multiple-choice Exit Exam was prepared by Electrical Engineering (EE) faculty members covering a poll of questions from EE core courses. A copy of the Exit Exam applied during each…

Abrupt Transitions for Youths Leaving School: Models of Interagency Cooperation.

ERIC Educational Resources Information Center

Karcz, Stanley A.; And Others

1985-01-01

Three programs that have been successful in facilitating the reenrollment of students from exiting juvenile detention facilities are described: the Lake County, IL, Youth Advocate Liaison Program; the Lake County, Florida, Multiagency/Special Education Program; and the Rock Island, Illinois, Coalition High School Model. (CL)

Theoretical study on the effect of the design of small (milli-Newton) thruster jets on molecular contamination for the space station

NASA Technical Reports Server (NTRS)

Riley, B. R.

1986-01-01

The self-induced molecular contamination around the space station could have adverse effects on space station components (for example solar panels) as well as scientific experiments that might be done on or near the space station. Aerospace engineers need to design a space station (SS) propulsion system that keeps the SS in a stable orbit and at the same time does not allow the propellant gases to interfere with the experiments of the user. One scenario that might accomplish the above requirements is to use an electrothermal propulsion system, resistojet, that will thrust continuously in the hundreds of milli-Newton range which will provide a constant altitude for the SS with a low g environment. As a first attempt to understand the contamination from such a propulsion system, a point source model was developed. The numerical results of the point source model are given. Number column densities for CO2 are presented as a function of direction of observation (line of sight), temperature of the exit gas, and mean exit velocity. All the results are for a constant exhaust rate of 5,000 kg/year. In addition, a mathematical model to study the effect of nozzle design on the induced molecular environment around the space station produced by simple gas propellants is described. The mathematical model would allow one to follow the expansion of the gas from the throat of a nozzle to the nozzle exit plane and then into the space external to the nozzle.

Multiphase Model of Semisolid Slurry Generation and Isothermal Holding During Cooling Slope Rheoprocessing of A356 Al Alloy

NASA Astrophysics Data System (ADS)

Das, Prosenjit; Samanta, Sudip K.; Mondal, Biswanath; Dutta, Pradip

2018-04-01

In the present paper, we present an experimentally validated 3D multiphase and multiscale solidification model to understand the transport processes involved during slurry generation with a cooling slope. In this process, superheated liquid alloy is poured at the top of the cooling slope and allowed to flow along the slope under the influence of gravity. As the melt flows down the slope, it progressively loses its superheat, starts solidifying at the melt/slope interface with formation of solid crystals, and eventually exits the slope as semisolid slurry. In the present simulation, the three phases considered are the parent melt as the primary phase, and the solid grains and air as secondary phases. The air phase forms a definable air/liquid melt interface as the free surface. After exiting the slope, the slurry fills an isothermal holding bath maintained at the slope exit temperature, which promotes further globularization of microstructure. The outcomes of the present model include prediction of volume fractions of the three different phases considered, grain evolution, grain growth, size, sphericity and distribution of solid grains, temperature field, velocity field, macrosegregation and microsegregation. In addition, the model is found to be capable of making predictions of morphological evolution of primary grains at the onset of isothermal coarsening. The results obtained from the present simulations are validated by performing quantitative image analysis of micrographs of the rapidly oil-quenched semisolid slurry samples, collected from strategic locations along the slope and from the isothermal slurry holding bath.

The structure of a market containing boundedly rational firms

NASA Astrophysics Data System (ADS)

Ibrahim, Adyda; Zura, Nerda; Saaban, Azizan

2017-11-01

The structure of a market is determined by the number of active firms in it. Over time, this number is affected by the exit of existing firms, called incumbents, and entries of new firms, called entrant. In this paper, we considered a market governed by the Cobb-Douglas utility function such that the demand function is isoelastic. Each firm is assumed to produce a single homogenous product under a constant unit cost. Furthermore, firms are assumed to be boundedly rational in adjusting their outputs at each period. A firm is considered to exit the market if its output is negative. In this paper, the market is assumed to have zero barrier-to-entry. Therefore, the exiting firm can reenter the market if its output is positive again, and new firms can enter the market easily. Based on these assumptions and rules, a mathematical model was developed and numerical simulations were run using Matlab. By setting certain values for the parameters in the model, initial numerical simulations showed that in the long run, the number of firms that manages to survive the market varies between zero to 30. This initial result is consistent with the idea that a zero barrier-to-entry may produce a perfectly competitive market.

Measurement of Initial Conditions at Nozzle Exit of High Speed Jets

NASA Technical Reports Server (NTRS)

Panda, J.; Zaman, K. B. M. Q.; Seasholtz, R. G.

2004-01-01

The time averaged and unsteady density fields close to the nozzle exit (0.1 less than or = x/D less than or = 2, x: downstream distance, D: jet diameter) of unheated free jets at Mach numbers of 0.95, 1.4, and 1.8 were measured using a molecular Rayleigh scattering based technique. The initial thickness of shear layer and its linear growth rate were determined from time-averaged density survey and a modeling process, which utilized the Crocco-Busemann equation to relate density profiles to velocity profiles. The model also corrected for the smearing effect caused by a relatively long probe length in the measured density data. The calculated shear layer thickness was further verified from a limited hot-wire measurement. Density fluctuations spectra, measured using a two-Photomultiplier-tube technique, were used to determine evolution of turbulent fluctuations in various Strouhal frequency bands. For this purpose spectra were obtained from a large number of points inside the flow; and at every axial station spectral data from all radial positions were integrated. The radially-integrated fluctuation data show an exponential growth with downstream distance and an eventual saturation in all Strouhal frequency bands. The initial level of density fluctuations was calculated by extrapolation to nozzle exit.

Differences in Student Achievement between Early-Exit and Late-Exit Bilingual Programs: A Multiyear, Statewide Investigation

ERIC Educational Resources Information Center

Martinez, Rosa Maria

2014-01-01

Purpose The purpose of this study was to examine the difference between two bilingual program types: traditional early-exit and late-exit bilingual programs and academic achievement using archival data from the Texas Education Agency Public Education Information Management System. An examination of academic achievement rates across a 3-year period…

Relationship between cattle temperament as determined by exit velocity carcass merit in beef cattle

USDA-ARS?s Scientific Manuscript database

The objective of this trial was to use cattle temperament, as determined by exit velocity only, as a means to evaluate the impact of temperament on carcass merit and the possible utilization of exit velocity alone as a sorting tool within the feedlot. At the time of processing, exit velocity and bod...

Exit Strategies: How Low-Performing High Schools Respond to High School Exit Examination Requirements

ERIC Educational Resources Information Center

Holme, Jennifer Jellison

2013-01-01

Background: Over the past several decades, a significant number of states have either adopted or increased high school exit examination requirements. Although these policies are intended to generate improvement in schools, little is known about how high schools are responding to exit testing pressures. Purpose: This study examined how five…

24 CFR 3280.106 - Exit facilities; egress windows and devices.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Exit facilities; egress windows and... § 3280.106 Exit facilities; egress windows and devices. (a) Every room designed expressly for sleeping purposes, unless it has an exit door (see § 3280.105), shall have at least one outside window or approved...

Exit Exams: Decreases or Increases the Dropout Rate

ERIC Educational Resources Information Center

Barnes, Teresa A.

2009-01-01

The purpose of this paper was to examine the impact of exit exams on the dropout rate. Data was gathered from several research articles. The most impressionable research revealed exit exams have a negative effect on minorities, especially black males. Results indicate by 2012, that exit exams in 25 states will affect 81 percent of minority high…

Rotor with Flattened Exit Pressure Profile

NASA Technical Reports Server (NTRS)

Baltas, Constantine (Inventor); Prasad, Dilip (Inventor); Gallagher, Edward J. (Inventor)

2015-01-01

A rotor blade comprises an airfoil extending radially from a root section to a tip section and axially from a leading edge to a trailing edge, the leading and trailing edges defining a curvature therebetween. The curvature determines a relative exit angle at a relative span height between the root section and the tip section, based on an incident flow velocity at the leading edge of the airfoil and a rotational velocity at the relative span height. In operation of the rotor blade, the relative exit angle determines a substantially flat exit pressure ratio profile for relative span heights from 75% to 95%, wherein the exit pressure ratio profile is constant within a tolerance of 10% of a maximum value of the exit pressure ratio profile.

Evaluation of the Performance and Flow in an Axial Compressor.

DTIC Science & Technology

1982-10-01

A Exit Rake P 11.00-P tP noz P2noz -PA SP-1 PHub - PA Exit Rake Pt11.50-Pt p - PA SP-1 PTip - PA Exit Rake Pt2.00-PPtpipe ATp Att Pspipe - PA SP-2...PTip - PA Exit Rake Pt6.50-Pt Inlet Rake Pt14.40-PA SP-8 PTip - PA Exit Rake Pt 17.00-Pt Inlet Rake Pt 1.30-PA SP-8 PHub - PA Exit Rake Pt17.50-Pt...Determination from Probe Pressures Pt (1) =((Pt=(1) + Phub ) + (Pt(1) + Pt(2)))/3 P t(2) P t(2) Pt (3) = t(3) P t(4) = (P t(3) + P t(4))/2 P t(5) =P t(4) Pt

Diminishing musyarakah investment model based on equity

NASA Astrophysics Data System (ADS)

Jaffar, Maheran Mohd; Zain, Shaharir Mohamad; Jemain, Abdul Aziz

2017-11-01

Most of the mudharabah and musyarakah contract funds are involved in debt financing. This does not support the theory that profit sharing contract is better than that of debt financing due to the sharing of risks and ownership of equity. Indeed, it is believed that Islamic banking is a financial model based on equity or musyarakah which emphasis on the sharing of risks, profit and loss in the investment between the investor and entrepreneur. The focus of this paper is to introduce the mathematical model that internalizes diminishing musyarakah, the sharing of profit and equity between entrepreneur and investor. The entrepreneur pays monthly-differed payment to buy out the equity that belongs to the investor (bank) where at the end of the specified period, the entrepreneur owns the business and the investor (bank) exits the joint venture. The model is able to calculate the amount of equity at any time for both parties and hence would be a guide in helping to estimate the value of investment should the entrepreneur or investor exit before the end of the specified period. The model is closer to the Islamic principles for justice and fairness.

Instrumentation Working Group Summary

NASA Technical Reports Server (NTRS)

Zaller, Michelle; Miake-Lye, Richard

1999-01-01

The Instrumentation Working Group compiled a summary of measurement techniques applicable to gas turbine engine aerosol precursors and particulates. An assessment was made of the limits, accuracy, applicability, and technology readiness of the various techniques. Despite advances made in emissions characterization of aircraft engines, uncertainties still exist in the mechanisms by which aerosols and particulates are produced in the near-field engine exhaust. To adequately assess current understanding of the formation of sulfuric acid aerosols in the exhaust plumes of gas turbine engines, measurements are required to determine the degree and importance of sulfur oxidation in the turbine and at the engine exit. Ideally, concentrations of all sulfur species would be acquired, with emphasis on SO2 and SO3. Numerous options exist for extractive and non-extractive measurement of SO2 at the engine exit, most of which are well developed. SO2 measurements should be performed first to place an upper bound on the percentage of SO2 oxidation. If extractive and non-extractive techniques indicate that a large amount of the fuel sulfur is not detected as SO2, then efforts are needed to improve techniques for SO3 measurements. Additional work will be required to account for the fuel sulfur in the engine exhaust. Chemical Ionization Mass Spectrometry (CI-MS) measurements need to be pursued, although a careful assessment needs to be made of the sampling line impact on the extracted sample composition. Efforts should also be placed on implementing non-intrusive techniques and extending their capabilities by maximizing exhaust coverage for line-of-sight measurements, as well as development of 2-D techniques, where feasible. Recommendations were made to continue engine exit and combustor measurements of particulates. Particulate measurements should include particle size distribution, mass fraction, hydration properties, and volatile fraction. However, methods to ensure that unaltered samples are obtained need to be developed. Particulate speciation was also assigned a high priority for quantifying the fractions of carbon soot, PAH, refractory materials, metals, sulfates, and nitrates. High priority was also placed on performing a comparison of particle sizing instruments. Concern was expressed by the workshop attendees who routinely make particulate measurements about the variation in number density measured during in-flight tests by different instruments. In some cases, measurements performed by different groups of researchers during the same flight tests showed an order of magnitude variation. Second priority was assigned to measuring concentrations of odd hydrogen and oxidizing species. Since OH, HO2, H2O2, and O are extremely reactive, non-extractive measurements are recommended. A combination of absorption and fluorescence is anticipated to be effective for OH measurements in the combustor and at the engine exit. Extractive measurements of HO2 have been made in the stratosphere, where the ambient level of OH is relatively low. Use of techniques that convert HO2 to OH for combustor and engine exit measurements needs to be evaluated, since the ratio of HO2/OH may be 1% or less at both the combustor and engine exit. CI-MS might be a viable option for H2O2, subject to sampling line conversion issues. However, H2O2 is a low priority oxidizing species in the combustor and at the engine exit. Two candidates for atomic oxygen measurements are Resonance Enhanced Multi-Photon Ionization (REMPI) and Laser-Induced Fluorescence (LIF). Particulate measurement by simultaneous extractive and non-extractive techniques was given equal priority to the oxidizer measurements. Concern was expressed over the ability of typical ground test sampling lines to deliver an unaltered sample to a remotely located instrument. It was suggested that the sampling probe and line losses be checked out by attempting measurements using an optical or non-extractive technique immediately upstream of the sampling probe. This is a possible application for Laser Induced Incandescence (LII) as a check on the volume fraction of soot. Optical measurements of size distribution are not well developed for ultrafine particles less than about 20 nm in diameter, so a non-extractive technique for particulate size distribution cannot be recommended without further development. Carbon dioxide measurements need to be made to complement other extractive measurement techniques. CO2 measurements enable conversion of other species concentrations to emission indices. Carbon monoxide, which acts as a sink for oxidizing species, should be measured using non-extractive techniques. CO can be rapidly converted to CO2 in extractive probes, and a comparison between extractive and non-extractive measurements should be performed. Development of non-extractive techniques would help to assess the degree of CO conversion, and might be needed to improve the concentration measurement accuracy. Measurements of NO(x) will continue to be critical due to the role of NO and NO2 in atmospheric chemistry, and their influence on atmospheric ozone. Time-resolved measurements of temperature, velocity, and species concentrations were included on the list of desired measurement. Thermocouples are typically adequate for engine exit measurements. PIV and LDV are well established for obtaining velocity profiles. The techniques are listed in the accompanying table; are divided into extractive and non-extractive techniques. Efforts were made to include a measurement uncertainty for each technique. An assessment of the technology readiness was included.

Burner Rig with an Unattached Duct for Evaluating the Erosion Resistance of Thermal Barrier Coatings

NASA Technical Reports Server (NTRS)

Miller, Robert A.; Kuczmarski, Maria A.; Zhu, Dongming

2011-01-01

Extensive computational fluid dynamics (CFD) modeling backed by experimental observation has demonstrated the feasibility of using an unattached duct to increase the velocity and spatial spread of erodent particles exiting from a burner rig. It was shown that gas velocity and temperature are mostly retained if the inner diameter of the unattached duct equaled the exit diameter of the burner rig nozzle. For particles having a mean diameter of 550 millimeters, the modeled velocity attained at a distance 2.0 in. (50.8 millimeters) beyond the exit of a 12 in. (305 millimeters) long duct was approximately twice as large as the velocity the same distance from the nozzle when the duct was not present. For finer particles, the relative enhancement was somewhat less approximately 1.5 times greater. CFD modeling was also used to guide the construction of a device for slowing down the velocity of the particles being injected into the burner rig. This device used a simple 45 degree fitting to slow the particle velocity in the feed line from 20 meters per second, which is in the range needed to convey the particles, to about 3 meters per second just as they are injected into the burner. This lower injection velocity would lessen the severity of the collision of large particles with the wall of the burner liner opposite the injection port, thereby reducing potential damage to the burner liner by high-velocity particles.

To Be or Not to Be an Entrepreneur: Applying a Normative Model to Career Decisions

ERIC Educational Resources Information Center

Callanan, Gerard A.; Zimmerman, Monica

2016-01-01

Reflecting the need for a better and broader understanding of the factors influencing the choices to enter into or exit an entrepreneurial career, this article applies a structured, normative model of career management to the career decision-making of entrepreneurs. The application of a structured model can assist career counselors, college career…

A smooth exit from eternal inflation?

NASA Astrophysics Data System (ADS)

Hawking, S. W.; Hertog, Thomas

2018-04-01

The usual theory of inflation breaks down in eternal inflation. We derive a dual description of eternal inflation in terms of a deformed Euclidean CFT located at the threshold of eternal inflation. The partition function gives the amplitude of different geometries of the threshold surface in the no-boundary state. Its local and global behavior in dual toy models shows that the amplitude is low for surfaces which are not nearly conformal to the round three-sphere and essentially zero for surfaces with negative curvature. Based on this we conjecture that the exit from eternal inflation does not produce an infinite fractal-like multiverse, but is finite and reasonably smooth.

Performance of a high-work, low-aspect-ratio turbine stator tested with a realistic inlet radial temperature gradient

NASA Technical Reports Server (NTRS)

Stabe, Roy G.; Schwab, John R.

1991-01-01

A 0.767-scale model of a turbine stator designed for the core of a high-bypass-ratio aircraft engine was tested with uniform inlet conditions and with an inlet radial temperature profile simulating engine conditions. The principal measurements were radial and circumferential surveys of stator-exit total temperature, total pressure, and flow angle. The stator-exit flow field was also computed by using a three-dimensional Navier-Stokes solver. Other than temperature, there were no apparent differences in performance due to the inlet conditions. The computed results compared quite well with the experimental results.

A novel method for patient exit and entrance dose prediction based on water equivalent path length measured with an amorphous silicon electronic portal imaging device.

PubMed

Kavuma, Awusi; Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

2010-01-21

In vivo dosimetry is one of the quality assurance tools used in radiotherapy to monitor the dose delivered to the patient. Electronic portal imaging device (EPID) images for a set of solid water phantoms of varying thicknesses were acquired and the data fitted onto a quadratic equation, which relates the reduction in photon beam intensity to the attenuation coefficient and material thickness at a reference condition. The quadratic model is used to convert the measured grey scale value into water equivalent path length (EPL) at each pixel for any material imaged by the detector. For any other non-reference conditions, scatter, field size and MU variation effects on the image were corrected by relative measurements using an ionization chamber and an EPID. The 2D EPL is linked to the percentage exit dose table, for different thicknesses and field sizes, thereby converting the plane pixel values at each point into a 2D dose map. The off-axis ratio is corrected using envelope and boundary profiles generated from the treatment planning system (TPS). The method requires field size, monitor unit and source-to-surface distance (SSD) as clinical input parameters to predict the exit dose, which is then used to determine the entrance dose. The measured pixel dose maps were compared with calculated doses from TPS for both entrance and exit depth of phantom. The gamma index at 3% dose difference (DD) and 3 mm distance to agreement (DTA) resulted in an average of 97% passing for the square fields of 5, 10, 15 and 20 cm. The exit dose EPID dose distributions predicted by the algorithm were in better agreement with TPS-calculated doses than phantom entrance dose distributions.

A novel method for patient exit and entrance dose prediction based on water equivalent path length measured with an amorphous silicon electronic portal imaging device

NASA Astrophysics Data System (ADS)

Kavuma, Awusi; Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

2010-01-01

In vivo dosimetry is one of the quality assurance tools used in radiotherapy to monitor the dose delivered to the patient. Electronic portal imaging device (EPID) images for a set of solid water phantoms of varying thicknesses were acquired and the data fitted onto a quadratic equation, which relates the reduction in photon beam intensity to the attenuation coefficient and material thickness at a reference condition. The quadratic model is used to convert the measured grey scale value into water equivalent path length (EPL) at each pixel for any material imaged by the detector. For any other non-reference conditions, scatter, field size and MU variation effects on the image were corrected by relative measurements using an ionization chamber and an EPID. The 2D EPL is linked to the percentage exit dose table, for different thicknesses and field sizes, thereby converting the plane pixel values at each point into a 2D dose map. The off-axis ratio is corrected using envelope and boundary profiles generated from the treatment planning system (TPS). The method requires field size, monitor unit and source-to-surface distance (SSD) as clinical input parameters to predict the exit dose, which is then used to determine the entrance dose. The measured pixel dose maps were compared with calculated doses from TPS for both entrance and exit depth of phantom. The gamma index at 3% dose difference (DD) and 3 mm distance to agreement (DTA) resulted in an average of 97% passing for the square fields of 5, 10, 15 and 20 cm. The exit dose EPID dose distributions predicted by the algorithm were in better agreement with TPS-calculated doses than phantom entrance dose distributions.

Mixing of Supersonic Jets in a RBCC Strutjet Propulsion System

NASA Technical Reports Server (NTRS)

Muller, S.; Hawk, Clark W.; Bakker, P. G.; Parkinson, D.; Turner, M.

1998-01-01

The Strutjet approach to Rocket Based Combined Cycle (RBCC) propulsion depends upon fuel-rich flows from the rocket nozzles and turbine exhaust products mixing with the ingested air for successful operation in the ramjet and scramjet modes. It is desirable to delay this mixing process in the air-augmented mode of operation present during take-off and low speed flight. A scale model of the Strutjet device was built and tested to investigate the mixing of the streams as a function of distance from the Strut exit plane in simulated sea level take-off conditions. The Planar Laser Induced Fluorescence (PLIF) diagnostic method has been employed to observe the mixing of the turbine exhaust gas with the gases from both the primary rockets and the ingested air. The ratio of the pressure in the turbine exhaust to that in the rocket nozzle wall at the point where the two jets meet, is the independent variable in these experiments. Tests were accomplished at values of 1.0 (the original design point), 1.5 and 2.0 for this parameter at 8 locations downstream of the rocket nozzle exit. The results illustrate the development of the mixing zone from the exit plane of the strut to a distance of about 18 equivalent rocket nozzle exit diameters downstream (18"). These images show the turbine exhaust to be confined until a short distance downstream. The expansion into the ingested air is more pronounced at a pressure ratio of 1.0 and 1.5 and shows that mixing with this air would likely begin at a distance of 2" downstream of the nozzle exit plane. Of the pressure ratios tested in this research, 2.0 is the best value for delaying the mixing at the operating conditions considered.

Previous anxiety and depression as risk factors for early labour force exit.

PubMed

Rudolph, Kara E; Eaton, William W

2016-04-01

Individuals with a history of mental illness have lower earnings than individuals without. A possible reason is that those with prior anxiety or depression may be more likely to exit the labour force prior to retirement age, but evidence has been mixed and limited. Our objective was to compare risk of early labour force exit between employed adults with a history of depression or anxiety versus those without, separately for men and women. We used data from the Baltimore Epidemiological Catchment Area Follow-up Cohort, which collected baseline data in 1981 and follow-up data 1993-1996 and 2004-2005. Cox proportional hazards models estimated the relative risk of labour force exit comparing those with versus without prior history of anxiety or depressive disorders. Women with prior anxiety or depression are at 37% increased risk of dropping out of the labour force as compared to women without, controlling for age, socioeconomic status, race and marital status (HR: 1.37, 95% CI 1.04 to 1.79). Men with prior anxiety or depression are 18% more likely to subsequently drop out of the labour force as compared to men without, controlling for the above confounders as well as veteran status, but this association is not statistically significant (HR: 1.18, 95% CI 0.72 to 1.27). Prior anxiety or depression increases risk of early labour force exit for women. These findings may help explain previously reported lower earnings among female individuals with a history of mental illness and highlight the importance of considering anxiety and depressive disorders in policies supporting labour force participation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Exponential model for option prices: Application to the Brazilian market

NASA Astrophysics Data System (ADS)

Ramos, Antônio M. T.; Carvalho, J. A.; Vasconcelos, G. L.

2016-03-01

In this paper we report an empirical analysis of the Ibovespa index of the São Paulo Stock Exchange and its respective option contracts. We compare the empirical data on the Ibovespa options with two option pricing models, namely the standard Black-Scholes model and an empirical model that assumes that the returns are exponentially distributed. It is found that at times near the option expiration date the exponential model performs better than the Black-Scholes model, in the sense that it fits the empirical data better than does the latter model.

Neutral beamline with improved ion energy recovery

DOEpatents

Kim, Jinchoon

1984-01-01

A neutral beamline employing direct energy recovery of unneutralized residual ions is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell, and thus improves the overall neutral beamline efficiency. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beam direction in the neutral izer exit region. The ions which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be loosely coupled. As a result, the fractional energy ions exiting the cell are reflected onto and collected at an interior wall of the neutralizer formed by the modified end geometry, and thus do not detract from the energy recovery efficiency of full energy ions exiting the cell. Electrons within the neutralizer are prevented from exiting the neutralizer end opening by the action of crossed fields drift (ExB) and are terminated to a collector collar around the downstream opening of the neutralizer. The correct combination of the extended neutralizer end structure and the magnet region is designed so as to maximize the exit of full energy ions and to contain the fractional energy ions.

Influences of exit and stair conditions on human evacuation in a dormitory

NASA Astrophysics Data System (ADS)

Lei, Wenjun; Li, Angui; Gao, Ran; Wang, Xiaowei

2012-12-01

Evacuation processes of students are investigated by experiment and simulation. The experiment is performed for students evacuating from a dormitory with an exit and stairs. FDS+Evac is proposed to simulate the exit and stair dynamics of occupant evacuation. Concerning the exit and stair widths, we put forward some useful standpoints. Good agreement is achieved between the predicted results and experimental results. With the increase of exit width, a significant stratification phenomenon will be found in flow rate. Stratification phenomenon is that two different stable flow rates will emerge during the evacuation. And the flow rate curve looks like a ladder. The larger the exit width, the earlier the stratification phenomenon appears. When exit width is more than 2.0 m, the flow rate of each exit width is divided into two stable stages, and the evacuation times show almost no change. The judgment that the existence of stairs causes flow stratification is reasonable. By changing the width of the stairs, we proved that judgment. The smaller the width of BC, the earlier the stratification appears. We found that scenario 5 is the most adverse circumstance. Those results are helpful in performance-based design of buildings.

Catalytic reactor for low-Btu fuels

DOEpatents

Smith, Lance; Etemad, Shahrokh; Karim, Hasan; Pfefferle, William C.

2009-04-21

An improved catalytic reactor includes a housing having a plate positioned therein defining a first zone and a second zone, and a plurality of conduits fabricated from a heat conducting material and adapted for conducting a fluid therethrough. The conduits are positioned within the housing such that the conduit exterior surfaces and the housing interior surface within the second zone define a first flow path while the conduit interior surfaces define a second flow path through the second zone and not in fluid communication with the first flow path. The conduit exits define a second flow path exit, the conduit exits and the first flow path exit being proximately located and interspersed. The conduits define at least one expanded section that contacts adjacent conduits thereby spacing the conduits within the second zone and forming first flow path exit flow orifices having an aggregate exit area greater than a defined percent of the housing exit plane area. Lastly, at least a portion of the first flow path defines a catalytically active surface.

Neutral beamline with improved ion energy recovery

DOEpatents

Dagenhart, William K.; Haselton, Halsey H.; Stirling, William L.; Whealton, John H.

1984-01-01

A neutral beamline generator with unneutralized ion energy recovery is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell of the beamline. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beamline in the cell exit region. The ions, which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage, are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be closely coupled. As a result, the fractional energy ions exiting the cell with the full energy ions are reflected back into the gas cell. Thus, the fractional energy ions do not detract from the energy recovery efficiency of full energy ions exiting the cell which can reach the ground potential interior surfaces of the beamline housing.

Association Between Health Plan Exit From Medicaid Managed Care and Quality of Care, 2006-2014

PubMed Central

Schpero, William L.; Schlesinger, Mark J.; Trivedi, Amal N.

2017-01-01

Importance State Medicaid programs have increasingly contracted with insurers to provide medical care services for enrollees (Medicaid managed care plans). Insurers that provide these plans can exit Medicaid programs each year, with unclear effects on quality of care and health care experiences. Objective To determine the frequency and interstate variation of health plan exit from Medicaid managed care and evaluate the relationship between health plan exit and market-level quality. Design, Setting, and Participants Retrospective cohort of all comprehensive Medicaid managed care plans (N = 390) during the interval 2006-2014. Exposures Plan exit, defined as the withdrawal of a managed care plan from a state’s Medicaid program. Main Outcomes and Measures Eight measures from the Healthcare Effectiveness Data and Information Set were used to construct 3 composite indicators of quality (preventive care, chronic disease care management, and maternity care). Four measures from the Consumer Assessment of Healthcare Providers and Systems were combined into a composite indicator of patient experience, reflecting the proportion of beneficiaries rating experiences as 8 or above on a 0-to-10–point scale. Outcome data were available for 248 plans (68% of plans operating prior to 2014, representing 78% of beneficiaries). Results Of the 366 comprehensive Medicaid managed care plans operating prior to 2014, 106 exited Medicaid. These exiting plans enrolled 4 848 310 Medicaid beneficiaries, with a mean of 606 039 beneficiaries affected by plan exits annually. Six states had a mean of greater than 10% of Medicaid managed care recipients enrolled in plans that exited, whereas 10 states experienced no plan exits. Plans that exited from a state’s Medicaid market performed significantly worse prior to exiting than those that remained in terms of preventive care (57.5% vs 60.4%; difference, 2.9% [95% CI, 0.3% to 5.5%]), maternity care (69.7% vs 73.6%; difference, 3.8% [95% CI, 1.7% to 6.0%]), and patient experience (73.5% vs 74.8%; difference, 1.3% [95% CI, 0.6% to 1.9%]). There was no significant difference between exiting and nonexiting plans for the quality of chronic disease care management (76.2% vs 77.1%; difference, 1.0% [95% CI, −2.1% to 4.0%]). There was also no significant change in overall market performance before and after the exit of a plan: 0.7–percentage point improvement in preventive care quality (95% CI, −4.9 to 6.3); 0.2–percentage point improvement in chronic disease care management quality (95% CI, −5.8 to 6.2); 0.7–percentage point decrease in maternity care quality (95% CI, −6.4 to 5.0]); and a 0.6–percentage point improvement in patient experience ratings (95% CI, −3.9 to 5.1). Medicaid beneficiaries enrolled in exiting plans had access to coverage for a higher-quality plan, with 78% of plans in the same county having higher quality for preventive care, 71.1% for chronic disease management, 65.5% for maternity care, and 80.8% for patient experience. Conclusions and Relevance Between 2006 and 2014, health plan exit from the US Medicaid program was frequent. Plans that exited generally had lower quality ratings than those that remained, and the exits were not associated with significant overall changes in quality or patient experience in the plans in the Medicaid market. PMID:28655014

Association Between Health Plan Exit From Medicaid Managed Care and Quality of Care, 2006-2014.

PubMed

Ndumele, Chima D; Schpero, William L; Schlesinger, Mark J; Trivedi, Amal N

2017-06-27

State Medicaid programs have increasingly contracted with insurers to provide medical care services for enrollees (Medicaid managed care plans). Insurers that provide these plans can exit Medicaid programs each year, with unclear effects on quality of care and health care experiences. To determine the frequency and interstate variation of health plan exit from Medicaid managed care and evaluate the relationship between health plan exit and market-level quality. Retrospective cohort of all comprehensive Medicaid managed care plans (N = 390) during the interval 2006-2014. Plan exit, defined as the withdrawal of a managed care plan from a state's Medicaid program. Eight measures from the Healthcare Effectiveness Data and Information Set were used to construct 3 composite indicators of quality (preventive care, chronic disease care management, and maternity care). Four measures from the Consumer Assessment of Healthcare Providers and Systems were combined into a composite indicator of patient experience, reflecting the proportion of beneficiaries rating experiences as 8 or above on a 0-to-10-point scale. Outcome data were available for 248 plans (68% of plans operating prior to 2014, representing 78% of beneficiaries). Of the 366 comprehensive Medicaid managed care plans operating prior to 2014, 106 exited Medicaid. These exiting plans enrolled 4 848 310 Medicaid beneficiaries, with a mean of 606 039 beneficiaries affected by plan exits annually. Six states had a mean of greater than 10% of Medicaid managed care recipients enrolled in plans that exited, whereas 10 states experienced no plan exits. Plans that exited from a state's Medicaid market performed significantly worse prior to exiting than those that remained in terms of preventive care (57.5% vs 60.4%; difference, 2.9% [95% CI, 0.3% to 5.5%]), maternity care (69.7% vs 73.6%; difference, 3.8% [95% CI, 1.7% to 6.0%]), and patient experience (73.5% vs 74.8%; difference, 1.3% [95% CI, 0.6% to 1.9%]). There was no significant difference between exiting and nonexiting plans for the quality of chronic disease care management (76.2% vs 77.1%; difference, 1.0% [95% CI, -2.1% to 4.0%]). There was also no significant change in overall market performance before and after the exit of a plan: 0.7-percentage point improvement in preventive care quality (95% CI, -4.9 to 6.3); 0.2-percentage point improvement in chronic disease care management quality (95% CI, -5.8 to 6.2); 0.7-percentage point decrease in maternity care quality (95% CI, -6.4 to 5.0]); and a 0.6-percentage point improvement in patient experience ratings (95% CI, -3.9 to 5.1). Medicaid beneficiaries enrolled in exiting plans had access to coverage for a higher-quality plan, with 78% of plans in the same county having higher quality for preventive care, 71.1% for chronic disease management, 65.5% for maternity care, and 80.8% for patient experience. Between 2006 and 2014, health plan exit from the US Medicaid program was frequent. Plans that exited generally had lower quality ratings than those that remained, and the exits were not associated with significant overall changes in quality or patient experience in the plans in the Medicaid market.

Bed occupancy monitoring: data processing and clinician user interface design.

PubMed

Pouliot, Melanie; Joshi, Vilas; Goubran, Rafik; Knoefel, Frank

2012-01-01

Unobtrusive and continuous monitoring of patients, especially at their place of residence, is becoming a significant part of the healthcare model. A variety of sensors are being used to monitor different patient conditions. Bed occupancy monitoring provides clinicians a quantitative measure of bed entry/exit patterns and may provide information relating to sleep quality. This paper presents a bed occupancy monitoring system using a bed pressure mat sensor. A clinical trial was performed involving 8 patients to collect bed occupancy data. The trial period for each patient ranged from 5-10 weeks. This data was analyzed using a participatory design methodology incorporating clinician feedback to obtain bed occupancy parameters. The parameters extracted include the number of bed exits per night, the bed exit weekly average (including minimum and maximum), the time of day of a particular exit, and the amount of uninterrupted bed occupancy per night. The design of a clinical user interface plays a significant role in the acceptance of such patient monitoring systems by clinicians. The clinician user interface proposed in this paper was designed to be intuitive, easy to navigate and not cause information overload. An iterative design methodology was used for the interface design. The interface design is extendible to incorporate data from multiple sensors. This allows the interface to be part of a comprehensive remote patient monitoring system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bühler, Stefan; Obrist, Dominik; Kleiser, Leonhard

We investigate numerically the effects of nozzle-exit flow conditions on the jet-flow development and the near-field sound at a diameter-based Reynolds number of Re{sub D} = 18 100 and Mach number Ma = 0.9. Our computational setup features the inclusion of a cylindrical nozzle which allows to establish a physical nozzle-exit flow and therefore well-defined initial jet-flow conditions. Within the nozzle, the flow is modeled by a potential flow core and a laminar, transitional, or developing turbulent boundary layer. The goal is to document and to compare the effects of the different jet inflows on the jet flow development and themore » sound radiation. For laminar and transitional boundary layers, transition to turbulence in the jet shear layer is governed by the development of Kelvin-Helmholtz instabilities. With the turbulent nozzle boundary layer, the jet flow development is characterized by a rapid changeover to a turbulent free shear layer within about one nozzle diameter. Sound pressure levels are strongly enhanced for laminar and transitional exit conditions compared to the turbulent case. However, a frequency and frequency-wavenumber analysis of the near-field pressure indicates that the dominant sound radiation characteristics remain largely unaffected. By applying a recently developed scaling procedure, we obtain a close match of the scaled near-field sound spectra for all nozzle-exit turbulence levels and also a reasonable agreement with experimental far-field data.« less

36 CFR 13.1326 - Snowmachines.

Code of Federal Regulations, 2014 CFR

2014-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...) On Exit Glacier Road; (b) In parking areas; (c) On a designated route through the Exit Glacier...

36 CFR 13.1326 - Snowmachines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...) On Exit Glacier Road; (b) In parking areas; (c) On a designated route through the Exit Glacier...

36 CFR 13.1326 - Snowmachines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...) On Exit Glacier Road; (b) In parking areas; (c) On a designated route through the Exit Glacier...

36 CFR 13.1326 - Snowmachines.

Code of Federal Regulations, 2010 CFR

2010-07-01

... NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Kenai Fjords National Park Exit Glacier Developed...) On Exit Glacier Road; (b) In parking areas; (c) On a designated route through the Exit Glacier...

Evaluation of Two Methods of Prompting Drivers to Use Specific Exits on Conflicts between Vehicles at the Critical Exit

ERIC Educational Resources Information Center

Van Houten, Ron; Malenfant, J. E. Louis; Zhao, Nan; Ko, Byungkon; Van Houten, Jonathan

2005-01-01

The Florida Department of Transportation used a series of changeable-message signs that functioned as freeway guide signs to divert traffic to Universal Theme Park via one of two eastbound exits based on traffic congestion at the first of the two exits. An examination of crashes along the entire route indicated a statistically significant increase…

To Leave or Not to Leave? A Regression Discontinuity Analysis of the Impact of Failing High School Exit Exam. CEE DP 107

ERIC Educational Resources Information Center

Ou, Dongshu

2009-01-01

This paper presents new empirical evidence on whether failing the high school exit exam increases the chance of exiting from high school "prior to high school completion". More importantly, the author discusses the potentially different impacts of failing the High School Exit Exams (HSEE) on students with limited English proficiency,…

Solar concentrator with restricted exit angles

DOEpatents

Rabl, Arnulf; Winston, Roland

1978-12-19

A device is provided for the collection and concentration of radiant energy and includes at least one reflective side wall. The wall directs incident radiant energy to the exit aperture thereof or onto the surface of energy absorber positioned at the exit aperture so that the angle of incidence of radiant energy at the exit aperture or on the surface of the energy absorber is restricted to desired values.

A theory of germinal center B cell selection, division, and exit.

PubMed

Meyer-Hermann, Michael; Mohr, Elodie; Pelletier, Nadége; Zhang, Yang; Victora, Gabriel D; Toellner, Kai-Michael

2012-07-26

High-affinity antibodies are generated in germinal centers in a process involving mutation and selection of B cells. Information processing in germinal center reactions has been investigated in a number of recent experiments. These have revealed cell migration patterns, asymmetric cell divisions, and cell-cell interaction characteristics, used here to develop a theory of germinal center B cell selection, division, and exit (the LEDA model). According to this model, B cells selected by T follicular helper cells on the basis of successful antigen processing always return to the dark zone for asymmetric division, and acquired antigen is inherited by one daughter cell only. Antigen-retaining B cells differentiate to plasma cells and leave the germinal center through the dark zone. This theory has implications for the functioning of germinal centers because compared to previous models, high-affinity antibodies appear one day earlier and the amount of derived plasma cells is considerably larger. Copyright © 2012 The Authors. Published by Elsevier Inc. All rights reserved.

Simulation of VSPT Experimental Cascade Under High and Low Free-Stream Turbulence Conditions

NASA Technical Reports Server (NTRS)

Ameri, Ali A.; Giel, Paul W.; Flegel, Ashlie B.

2014-01-01

Variable-Speed Power Turbines (VSPT) for rotorcraft applications operate at low Reynolds number and over a wide range in incidence associated with shaft speed change. A comprehensive linear cascade data set obtained includes the effects of Reynolds number, free-stream turbulence and incidence is available and this paper concerns itself with the presentation and numerical simulation of conditions resulting in a selected set of those data. As such, post-dictions of blade pressure loading, total-pressure loss and exit flow angles under conditions of high and low turbulence intensity for a single Reynolds number are presented. Analyses are performed with the three-equation turbulence models of Walters-Leylek and Walters and Cokljat. Transition, loading, total-pressure loss and exit angle variations are presented and comparisons are made with experimental data as available. It is concluded that at the low freestream turbulence conditions the Walters-Cokljat model is better suited to predictions while for high freestream conditions the two models generate similar predications that are generally satisfactory.

Cosmic reionization on computers. Ultraviolet continuum slopes and dust opacities in high redshift galaxies

DOE PAGES

Khakhaleva-Li, Zimu; Gnedin, Nickolay Y.

2016-03-30

In this study, we compare the properties of stellar populations of model galaxies from the Cosmic Reionization On Computers (CROC) project with the exiting UV and IR data. Since CROC simulations do not follow cosmic dust directly, we adopt two variants of the dust-follows-metals ansatz to populate model galaxies with dust. Using the dust radiative transfer code Hyperion, we compute synthetic stellar spectra, UV continuum slopes, and IR fluxes for simulated galaxies. We find that the simulation results generally match observational measurements, but, perhaps, not in full detail. The differences seem to indicate that our adopted dust-follows-metals ansatzes are notmore » fully sufficient. While the discrepancies with the exiting data are marginal, the future JWST data will be of much higher precision, rendering highly significant any tentative difference between theory and observations. It is, therefore, likely, that in order to fully utilize the precision of JWST observations, fully dynamical modeling of dust formation, evolution, and destruction may be required.« less

Simulation of VSPT Experimental Cascade Under High and Low Free-Stream Turbulence Conditions

NASA Technical Reports Server (NTRS)

Ameri, Ali A.; Giel, Paul W.; Flegel, Ashlie B.

2015-01-01

Variable-Speed Power Turbines (VSPT) for rotorcraft applications operate at low Reynolds number and over a wide range in incidence associated with shaft speed change. A comprehensive linear cascade data set obtained includes the effects of Reynolds number, free-stream turbulence and incidence is available and this paper concerns itself with the presentation and numerical simulation of conditions resulting in a selected set of those data. As such, post-dictions of blade pressure loading, total-pressure loss and exit flow angles under conditions of high and low turbulence intensity for a single Reynolds number are presented. Analyses are performed with the three-equation turbulence models of Walters- Leylek and Walters and Cokljat. Transition, loading, total-pressure loss and exit angle variations are presented and comparisons are made with experimental data as available. It is concluded that at the low freestream turbulence conditions the Walters-Cokljat model is better suited to predictions while for high freestream conditions the two models generate similar predications that are generally satisfactory.

Cosmic reionization on computers. Ultraviolet continuum slopes and dust opacities in high redshift galaxies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khakhaleva-Li, Zimu; Gnedin, Nickolay Y.

In this study, we compare the properties of stellar populations of model galaxies from the Cosmic Reionization On Computers (CROC) project with the exiting UV and IR data. Since CROC simulations do not follow cosmic dust directly, we adopt two variants of the dust-follows-metals ansatz to populate model galaxies with dust. Using the dust radiative transfer code Hyperion, we compute synthetic stellar spectra, UV continuum slopes, and IR fluxes for simulated galaxies. We find that the simulation results generally match observational measurements, but, perhaps, not in full detail. The differences seem to indicate that our adopted dust-follows-metals ansatzes are notmore » fully sufficient. While the discrepancies with the exiting data are marginal, the future JWST data will be of much higher precision, rendering highly significant any tentative difference between theory and observations. It is, therefore, likely, that in order to fully utilize the precision of JWST observations, fully dynamical modeling of dust formation, evolution, and destruction may be required.« less

The effects of exit from work on health across different socioeconomic groups: A systematic literature review.

PubMed

Schaap, Rosanne; de Wind, Astrid; Coenen, Pieter; Proper, Karin; Boot, Cécile

2018-02-01

Exit from work leads to different effects on health, partially depending on the socioeconomic status (SES) of people in the work exit. Several studies on the effects of exit from work on health across socioeconomic groups have been performed, but results are conflicting. The aim of this review is to systematically review the available evidence regarding the effects of exit from work on health in high and low socioeconomic groups. A systematic literature search was conducted using Pubmed, Embase, Web of Science, CINAHL and PsycINFO. Search terms related to exit from work, health, SES and design (prospective or retrospective). Articles were included if they focused on: exit from work (early/statutory retirement, unemployment or disability pension); health (general, physical or mental health and/or health behaviour); SES (educational, occupational and/or income level); and inclusion of stratified or interaction analyses to determine differences across socioeconomic groups. This search strategy resulted in 22 studies. For general, physical or mental health and health behaviour, 13 studies found more positive effects of exit from work on health among employees with a higher SES compared to employees with a lower SES. These effects were mainly found after early/statutory retirement. In conclusion, the effects of exit from work, or more specific the effects of early/statutory retirement on health are different across socioeconomic groups. However, the findings of this review should be interpreted with caution as the studies used heterogeneous health outcomes and on each health outcome a limited number of studies was included. Yet, the positive effects of exit from work on health are mainly present in higher socioeconomic groups. Therefore, public health policies should focus on improving health of employees with a lower SES, in particular after exit from work to decrease health inequalities. Copyright © 2017 Elsevier Ltd. All rights reserved.

Suicide, Canadian law, and Exit International's "peaceful pill".

PubMed

Ogden, Russel D

2010-11-01

Australia's Exit International ("Exit") is probably the most visible and controversial right-to-die organization in the world. Founded by Dr. Philip Nitschke, Exit is known for do-it-yourself ("DIY") suicide workshops and a book banned in Australia: The Peaceful Pill Handbook. In 2009, Exit held its first workshop in Canada. Due to legal concerns, the Vancouver Public Library reneged on a commitment to give Exit a venue, so the workshop proceeded in the sanctuary of a church hall. This article summarizes the history of suicide law in Canada and gives an overview of the emerging DIY movement. A case report describes how a Canadian woman studied Exit's literature and learned how to import veterinary pentobarbital. In accordance with Exit's information, she ended her life. Ethical and legal implications for researching DIY suicide are discussed and it is argued that prohibition contributes to an undesirable situation of uncontrolled and unregulated suicide. Whether they are prohibited, permitted, or tolerated, suicide and assisted suicide are controversial. Their legal treatment in Canada is conflicting because suicide is not a crime but it is a serious offense to assist, encourage, or counsel someone to suicide. Individuals can lawfully take their lives, but they must act independently. This legal situation has given rise to a do-it-yourself ("DIY") right-to-die movement dedicated to technologies and information to enhance the possibilities for planned and humane suicide, while limiting the legal exposure of sympathetic third parties (Martin, 2010; Ogden 2001). My aim is to summarize the legal history of suicide in Canada and discuss the emerging social movement for DIY suicide and assistance in suicide. Exit International ("Exit"), based in Australia, is a leading organization in this movement. I present a case report that describes how a Canadian woman ended her life using DIY techniques learned from Exit. Some ethical and legal implications for researching DIY suicide are discussed. I argue that the DIY movement is an undesirable consequence of prohibition.

A hybrid modeling approach for option pricing

NASA Astrophysics Data System (ADS)

Hajizadeh, Ehsan; Seifi, Abbas

2011-11-01

The complexity of option pricing has led many researchers to develop sophisticated models for such purposes. The commonly used Black-Scholes model suffers from a number of limitations. One of these limitations is the assumption that the underlying probability distribution is lognormal and this is so controversial. We propose a couple of hybrid models to reduce these limitations and enhance the ability of option pricing. The key input to option pricing model is volatility. In this paper, we use three popular GARCH type model for estimating volatility. Then, we develop two non-parametric models based on neural networks and neuro-fuzzy networks to price call options for S&P 500 index. We compare the results with those of Black-Scholes model and show that both neural network and neuro-fuzzy network models outperform Black-Scholes model. Furthermore, comparing the neural network and neuro-fuzzy approaches, we observe that for at-the-money options, neural network model performs better and for both in-the-money and an out-of-the money option, neuro-fuzzy model provides better results.

The predictive performance of a path-dependent exotic-option credit risk model in the emerging market

NASA Astrophysics Data System (ADS)

Chen, Dar-Hsin; Chou, Heng-Chih; Wang, David; Zaabar, Rim

2011-06-01

Most empirical research of the path-dependent, exotic-option credit risk model focuses on developed markets. Taking Taiwan as an example, this study investigates the bankruptcy prediction performance of the path-dependent, barrier option model in the emerging market. We adopt Duan's (1994) [11], (2000) [12] transformed-data maximum likelihood estimation (MLE) method to directly estimate the unobserved model parameters, and compare the predictive ability of the barrier option model to the commonly adopted credit risk model, Merton's model. Our empirical findings show that the barrier option model is more powerful than Merton's model in predicting bankruptcy in the emerging market. Moreover, we find that the barrier option model predicts bankruptcy much better for highly-leveraged firms. Finally, our findings indicate that the prediction accuracy of the credit risk model can be improved by higher asset liquidity and greater financial transparency.

Investigation of non-Gaussian effects in the Brazilian option market

NASA Astrophysics Data System (ADS)

Sosa-Correa, William O.; Ramos, Antônio M. T.; Vasconcelos, Giovani L.

2018-04-01

An empirical study of the Brazilian option market is presented in light of three option pricing models, namely the Black-Scholes model, the exponential model, and a model based on a power law distribution, the so-called q-Gaussian distribution or Tsallis distribution. It is found that the q-Gaussian model performs better than the Black-Scholes model in about one third of the option chains analyzed. But among these cases, the exponential model performs better than the q-Gaussian model in 75% of the time. The superiority of the exponential model over the q-Gaussian model is particularly impressive for options close to the expiration date, where its success rate rises above ninety percent.

Factors Associated With Premature Exits From Supported Housing

PubMed Central

Gabrielian, Sonya; Burns, Alaina V.; Nanda, Nupur; Hellemann, Gerhard; Kane, Vincent; Young, Alexander S.

2015-01-01

Objective Many homeless consumers who enroll in supported housing programs—which offer subsidized housing and supportive services—disengage prematurely, before placement in permanent community-based housing. This study explored factors associated with exiting a supported housing program before achieving housing placement. Methods With the use of administrative data, a roster was obtained for consumers enrolled in the Veterans Affairs (VA) Greater Los Angeles supported housing program from 2011 to 2012. Fewer (4%) consumers exited this program before achieving housing (“exiters”) compared with consumers described in national VA figures (18%). Exiters with available demographic data (N=51) were matched 1:1 on age, gender, marital status, and race-ethnicity with consumers housed through this program (“stayers,” N=51). Medical records were reviewed to compare diagnoses, health care utilization, housing histories, vocational history, and criminal justice involvement of exiters versus stayers. Exiters' housing outcomes were identified. Recursive partitioning identified variables that best differentiated exiters from stayers. Results Several factors were associated with premature exits from this supported housing program: residing in temporary housing on hospital grounds during program enrollment, poor adherence to outpatient care, substance use disorders, hepatitis C, chronic pain, justice involvement, frequent emergency department utilization, and medical-surgical admissions. The first of these factors and poor adherence to outpatient medical-surgical care best differentiated exiters from stayers. Moreover, >50% of exiters became street homeless or incarcerated after leaving the program. Conclusions In that diverse social factors, diagnoses, and health care utilization patterns were associated with premature disengagement from supported housing, future research is needed to implement and evaluate rehabilitative services that address these factors, adapted to the context of supported housing. PMID:26467908

The Impact of Price-cap Regulations on Exit by Generic Pharmaceutical Firms.

PubMed

Zhang, Wei; Guh, Daphne; Sun, Huiying; Marra, Carlo A; Lynd, Larry D; Anis, Aslam H

2016-09-01

In 1998, the Province of Ontario in Canada adopted price-cap "70/90" regulations whereby the first generic entrant was required to be priced at ≤70% of the associated brand-name product and subsequent generics were priced at ≤90% of the first generic price. The price-caps were further lowered to 50% in 2006 and 25% in 2010. This study assessed the impact of such price-cap regulations on exit by generic drug firms. Formulary (2003-2012) listings of prescription drugs covered under the Ontario Drug Benefit program were used. The formulary tracks the "status" (on formulary, discontinued by manufacturer, and delisted for other reasons) for each drug. Markets were defined based on unique active ingredient and form within Ontario. Firm exit occurred when a manufacturer discontinued all its generic drugs within a market. The exit rate was defined as the number of generic firm-market exits divided by total generic firm-market follow-up years. Poisson regression was used to compare the exit rates during the 3 policy periods ("25," "50," and "70/90"). A total of 1126 generic manufacturers paired with 290 markets were identified. The exit rate ratio during the 25% price-cap period compared with the 70%/90% period was 2.42 (95% confidence interval, 1.56-3.77). A small manufacturer or a manufacturer in a market with ≥3 competitors or in an older market was more likely to exit. Lowering the price-cap level is associated with a higher incidence of generic firm exit from markets. Continuously reducing price-caps may have the unintended consequence of forcing generic firms to exit.

14 CFR 25.811 - Emergency exit marking.

Code of Federal Regulations, 2011 CFR

2011-01-01

... passenger emergency exit, or at another overhead location if it is more practical because of low headroom... divider that prevents fore and aft vision along the passenger cabin to indicate emergency exits beyond and...

14 CFR 25.811 - Emergency exit marking.

Code of Federal Regulations, 2013 CFR

2013-01-01

... passenger emergency exit, or at another overhead location if it is more practical because of low headroom... divider that prevents fore and aft vision along the passenger cabin to indicate emergency exits beyond and...

14 CFR 25.811 - Emergency exit marking.

Code of Federal Regulations, 2014 CFR

2014-01-01

... passenger emergency exit, or at another overhead location if it is more practical because of low headroom... divider that prevents fore and aft vision along the passenger cabin to indicate emergency exits beyond and...

14 CFR 25.811 - Emergency exit marking.

Code of Federal Regulations, 2012 CFR

2012-01-01

... passenger emergency exit, or at another overhead location if it is more practical because of low headroom... divider that prevents fore and aft vision along the passenger cabin to indicate emergency exits beyond and...

14 CFR 25.811 - Emergency exit marking.

Code of Federal Regulations, 2010 CFR

2010-01-01

... passenger emergency exit, or at another overhead location if it is more practical because of low headroom... divider that prevents fore and aft vision along the passenger cabin to indicate emergency exits beyond and...

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aho, Michael E.; Attinella, John E.; Gooding, Thomas M.

Aggregating job exit statuses of a plurality of compute nodes executing a parallel application, including: identifying a subset of compute nodes in the parallel computer to execute the parallel application; selecting one compute node in the subset of compute nodes in the parallel computer as a job leader compute node; initiating execution of the parallel application on the subset of compute nodes; receiving an exit status from each compute node in the subset of compute nodes, where the exit status for each compute node includes information describing execution of some portion of the parallel application by the compute node; aggregatingmore » each exit status from each compute node in the subset of compute nodes; and sending an aggregated exit status for the subset of compute nodes in the parallel computer.« less

Medicare payment reform and provider entry and exit in the post-acute care market.

PubMed

Huckfeldt, Peter J; Sood, Neeraj; Romley, John A; Malchiodi, Alessandro; Escarce, José J

2013-10-01

To understand the impacts of Medicare payment reform on the entry and exit of post-acute providers. Medicare Provider of Services data, Cost Reports, and Census data from 1991 through 2010. We examined market-level changes in entry and exit after payment reforms relative to a preexisting time trend. We also compared changes in high Medicare share markets relative to lower Medicare share markets and for freestanding relative to hospital-based facilities. We calculated market-level entry, exit, and total stock of home health agencies, skilled nursing facilities, and inpatient rehabilitation facilities from Provider of Services files between 1992 and 2010. We linked these measures with demographic information from the Census and American Community Survey, information on Certificate of Need laws, and Medicare share of facilities in each market drawn from Cost Report data. Payment reforms reducing average and marginal payments reduced entries and increased exits from the market. Entry effects were larger and more persistent than exit effects. Entry and exit rates fluctuated more for home health agencies than skilled nursing facilities. Effects on number of providers were consistent with entry and exit effects. Payment reform affects market entry and exit, which in turn may affect market structure, access to care, quality and cost of care, and patient outcomes. Policy makers should consider potential impacts of payment reforms on post-acute care market structure when implementing these reforms. © Health Research and Educational Trust.

Medicare Payment Reform and Provider Entry and Exit in the Post-Acute Care Market

PubMed Central

Huckfeldt, Peter J; Sood, Neeraj; Romley, John A; Malchiodi, Alessandro; Escarce, José J

2013-01-01

Objective To understand the impacts of Medicare payment reform on the entry and exit of post-acute providers. Data Sources Medicare Provider of Services data, Cost Reports, and Census data from 1991 through 2010. Study Design We examined market-level changes in entry and exit after payment reforms relative to a preexisting time trend. We also compared changes in high Medicare share markets relative to lower Medicare share markets and for freestanding relative to hospital-based facilities. Data Extraction Methods We calculated market-level entry, exit, and total stock of home health agencies, skilled nursing facilities, and inpatient rehabilitation facilities from Provider of Services files between 1992 and 2010. We linked these measures with demographic information from the Census and American Community Survey, information on Certificate of Need laws, and Medicare share of facilities in each market drawn from Cost Report data. Principal Findings Payment reforms reducing average and marginal payments reduced entries and increased exits from the market. Entry effects were larger and more persistent than exit effects. Entry and exit rates fluctuated more for home health agencies than skilled nursing facilities. Effects on number of providers were consistent with entry and exit effects. Conclusions Payment reform affects market entry and exit, which in turn may affect market structure, access to care, quality and cost of care, and patient outcomes. Policy makers should consider potential impacts of payment reforms on post-acute care market structure when implementing these reforms. PMID:23557215

Valuing options in shot noise market

NASA Astrophysics Data System (ADS)

Laskin, Nick

2018-07-01

A new exactly solvable option pricing model has been introduced and elaborated. It is assumed that a stock price follows a Geometric shot noise process. An arbitrage-free integro-differential option pricing equation has been obtained and solved. The new Greeks have been analytically calculated. It has been shown that in diffusion approximation the developed option pricing model incorporates the well-known Black-Scholes equation and its solution. The stochastic dynamic origin of the Black-Scholes volatility has been uncovered. To model the observed market stock price patterns consisting of high frequency small magnitude and low frequency large magnitude jumps, the superposition of two Geometric shot noises has been implemented. A new generalized option pricing equation has been obtained and its exact solution was found. Merton's jump-diffusion formula for option price was recovered in diffusion approximation. Despite the non-Gaussian nature of probability distributions involved, the new option pricing model has the same degree of analytical tractability as the Black-Scholes model and the Merton jump-diffusion model. This attractive feature allows one to derive exact formulas to value options and option related instruments in the market with jump-like price patterns.

An accurate European option pricing model under Fractional Stable Process based on Feynman Path Integral

NASA Astrophysics Data System (ADS)

Ma, Chao; Ma, Qinghua; Yao, Haixiang; Hou, Tiancheng

2018-03-01

In this paper, we propose to use the Fractional Stable Process (FSP) for option pricing. The FSP is one of the few candidates to directly model a number of desired empirical properties of asset price risk neutral dynamics. However, pricing the vanilla European option under FSP is difficult and problematic. In the paper, built upon the developed Feynman Path Integral inspired techniques, we present a novel computational model for option pricing, i.e. the Fractional Stable Process Path Integral (FSPPI) model under a general fractional stable distribution that tackles this problem. Numerical and empirical experiments show that the proposed pricing model provides a correction of the Black-Scholes pricing error - overpricing long term options, underpricing short term options; overpricing out-of-the-money options, underpricing in-the-money options without any additional structures such as stochastic volatility and a jump process.

Effect of slotted exit orifice on performance of plasma synthetic jet actuator

NASA Astrophysics Data System (ADS)

Zong, Haohua; Kotsonis, Marios

2017-03-01

This study experimentally investigates the influence of exit orifice shape on the performance characteristics of a three-electrode plasma synthetic jet actuator. High-speed Schlieren imaging system and phase-locked two-component PIV measurements are used for flowfield characterisation in quiescent conditions. Two actuator configurations with the same exit area but different exit orifice shape (round orifice and slot orifice) are studied. Results indicate a close correspondence between the shapes of the starting vortex ring with the shapes of the respective exit orifices. For the slot orifice, the elongated starting vortex ring gradually expands during propagation, while its ends become warped. A distinct K-H instability structure is observed, inducing continuous oscillation of the high-speed jet. Compared with the jet from the round orifice, the slot jet has a higher entrainment rate of surrounding air, thus resulting in a lower propagation velocity of the jet front. The exit velocity of PSJA within one period initially shows a rapid increase, then persists at a relatively high level (100-130 m/s), and finally drops with some small-scale oscillations. The oscillation amplitude is less than 10 m/s, and the oscillation period is approximately 600 µs. Under conditions of same exit area, orifice shape has little influence on the variation of the exit velocity.

Sensitivity of Runway Occupancy Time (ROT) to Various Rollout and Turnoff (ROTO) Factors. Volume 1

NASA Technical Reports Server (NTRS)

Goldthorpe, S. H.

1997-01-01

The Terminal Area Productivity (TAP) research program was initiated by NASA to increase the airport capacity for transport aircraft operations. One element of the research program is called Low Visibility Landing and Surface Operations (LVLASO). A goal of the LVLASO research is to develop transport aircraft technologies which reduce Runway Occupancy Time (ROT) so that it does not become the limiting factor in the terminal area operations that determine the capacity of a runway. Under LVLASO, the objective of this study was to determine the sensitivity of ROT to various factors associated with the Rollout and Turnoff (ROTO) operation for transport aircraft. The following operational factors were studied and are listed in the order of decreasing ROT sensitivity: ice/flood runway surface condition, exit entrance ground speed, number of exits, high-speed exit locations and spacing, aircraft type, touchdown ground speed standard deviation, reverse thrust and braking method, accurate exit prediction capability, maximum reverse thrust availability, spiral-arc vs. circle-arc exit geometry, dry/slush/wet/snow runway surface condition, maximum allowed deceleration, auto asymmetric braking on exit, do not stow reverse thrust before the exit, touchdown longitudinal location standard deviation, flap setting, anti-skid efficiency, crosswind conditions, stopping on the exit and touchdown lateral offset.

Sensitivity of Runway Occupancy Time (ROT) to Various Rollout and Turnoff (ROTO) Factors. Volume 2; Complete Set of Plotted Data

NASA Technical Reports Server (NTRS)

Goldthorpe, S. H.

1997-01-01

The Terminal Area Productivity (TAP) research program was initiated by NASA to increase the airport capacity for transport aircraft operations. One element of the research program is called Low Visibility Landing and Surface Operations (LVLASO). A goal of the LVLASO research is to develop transport aircraft technologies which reduce Runway Occupancy Time (ROT) so that it does not become the limiting factor in the terminal area operations that determine the capacity of a runway. Under LVLASO, the objective of this study was to determine the sensitivity of ROT to various factors associated with the Rollout and Turnoff (ROTO) operation for transport aircraft. The following operational factors were studied and are listed in the order of decreasing ROT sensitivity: ice/flood runway surface condition, exit entrance ground speed, number of exits, high-speed exit locations and spacing, aircraft type, touchdown ground speed standard deviation, reverse thrust and braking method, accurate exit prediction capability, maximum reverse thrust availability, spiral-arc vs. circle-arc exit geometry, dry/slush/wet/snow runway surface condition, maximum allowed deceleration, auto asymmetric braking on exit, do not stow reverse thrust before the exit, touchdown longitudinal location standard deviation, flap setting, anti-skid efficiency, crosswind conditions, stopping on the exit and touchdown lateral offset.

Understanding Self-Sufficiency of Welfare Leavers in Illinois: Elaborating Models with Psychosocial Factors.

ERIC Educational Resources Information Center

Julnes, George; Fan, Xitao; Hayashi, Kentaro

2001-01-01

Used survey (for 1,001 adults) and administrative data (for 137,330 first-exit cases) in structural equation modeling to examine psychological and social factors as determinants of welfare dependency and self-sufficiency. Findings show well-being to be a predictor of low recidivism and high employment. (SLD)

Foam-on-Tile Damage Model

NASA Technical Reports Server (NTRS)

Koharchik, Michael; Murphy, Lindsay; Parker, Paul

2012-01-01

An impact model was developed to predict how three specific foam types would damage the Space Shuttle Orbiter insulating tiles. The inputs needed for the model are the foam type, the foam mass, the foam impact velocity, the foam impact incident angle, the type being impacted, and whether the tile is new or aged (has flown at least one mission). The model will determine if the foam impact will cause damage to the tile. If it can cause damage, the model will output the damage cavity dimensions (length, depth, entry angle, exit angle, and sidewall angles). It makes the calculations as soon as the inputs are entered (less than 1 second). The model allows for the rapid calculation of numerous scenarios in a short time. The model was developed from engineering principles coupled with significant impact testing (over 800 foam impact tests). This model is applicable to masses ranging from 0.0002 up to 0.4 pound (0.09 up to 181 g). A prior tool performed a similar function, but was limited to the assessment of a small range of masses and did not have the large test database for verification. In addition, the prior model did not provide outputs of the cavity damage length, entry angle, exit angle, or sidewall angles.

Effect of impinging plate geometry on the self-excitation of subsonic impinging jets

NASA Astrophysics Data System (ADS)

Vinoth, B. R.; Rathakrishnan, E.

2011-11-01

In the generation of discrete tones by subsonic impinging jets, there exists a difference of opinion as how the feedback is achieved, i.e., the path of the feedback acoustic waves is whether inside the jet or outside the jet? The only available model (Tam and Ahuja model) for the prediction of an average subsonic jet impingement tone frequency assumes that the upstream part of the feedback loop is closed by an upstream propagating neutral wave of the jet. But, there is no information about the plate geometry in the model. The present study aims at understanding the effect of the plate geometry (size and co-axial hole in the plate) on the self-excitation process of subsonic impinging jets and the path of the acoustic feedback to the nozzle exit. The present results show that there is no effect of plate diameter on the frequency of the self-excitation. A new type of tones is generated for plates with co-axial hole (hole diameter is equal to nozzle exit diameter) for Mach numbers 0.9 and 0.95, in addition to the axisymmetric and helical mode tones observed for plates without co-axial hole. The stability results show that the Strouhal number of the least dispersive upstream propagating neutral waves match with the average Strouhal number of the new tones observed in the present experiments. The present study extends the validity of the model of Tam and Ahuja to a plate with co-axial hole (annular plate) and by doing so, we indirectly confirmed that the major acoustic feedback path to the nozzle exit is inside the jet.

Developing a global health diplomacy supply chain--a viable option for the United States to curb extremism.

PubMed

Kumar, Sameer; Honkanen, Erik J; Karl, Chad C

2009-01-01

This study examines the idea of developing a global health diplomacy supply chain as an important foreign policy approach with the aim of improving the lives of vulnerable populations and serving the best interests of the United States. The study was based on the review of academic literature, news events, and military communiques, and historical writings were studied to determine the feasibility of the idea and the extent of costs and benefits of such an endeavor. An integrated strategic business model, supported by a medical care delivery process, was developed to create a framework for a feasible global health diplomacy supply chain. The findings indicate that extremism can be contained by creating and efficiently executing an effective supply chain to get medical care units to those that need them. The limitations are the potential exit strategies required, the tactical abilities, and diplomatic techniques needed in order to create positive diplomatic change in aid distribution. Managers must consider how supply chains will affect other organizations giving aid and the potential public response. Moreover, determining the level of care necessary to achieve the greatest positive health diplomacy continues to require vigilant scrutiny over the potential cost/benefit analysis. The analysis is valuable to policymakers considering the impacts of health diplomacy by utilizing supply chain management.

Design and Off-Design Performance of 100 kWe-Class Brayton Power Conversion Systems

NASA Technical Reports Server (NTRS)

Johnson, Paul K.; Mason, Lee S.

2005-01-01

The NASA Glenn Research Center in-house computer model Closed Cycle Engine Program (CCEP) was used to explore the design trade space and off-design performance characteristics of 100 kWe-class recuperated Closed Brayton Cycle (CBC) power conversion systems. Input variables for a potential design point included the number of operating units (1, 2, 4), cycle peak pressure (0.5, 1, 2 MPa), and turbo-alternator shaft speed (30, 45, 60 kRPM). The design point analysis assumed a fixed turbine inlet temperature (1150 K), compressor inlet temperature (400 K), helium-xenon working-fluid molecular weight (40 g/mol), compressor pressure ratio (2.0), recuperator effectiveness (0.95), and a Sodium-Potassium (NaK) pumped-loop radiator. The design point options were compared on the basis of thermal input power, radiator area, and mass. For a nominal design point with defined Brayton components and radiator area, off-design cases were examined by reducing turbine inlet temperature (as low as 900 K), reducing shaft speed (as low as 50 percent of nominal), and circulating a percentage (up to 20 percent) of the compressor exit flow back to the gas cooler. The off-design examination sought approaches to reduce thermal input power without freezing the radiator.

Design and Off-Design Performance of 100 kWe-Class Brayton Power Conversion Systems

NASA Astrophysics Data System (ADS)

Johnson, Paul K.; Mason, Lee S.

2005-02-01

The NASA Glenn Research Center in-house computer model Closed Cycle Engine Program (CCEP) was used to explore the design trade space and off-design performance characteristics of 100 kWe-class recuperated Closed Brayton Cycle (CBC) power conversion systems. Input variables for a potential design point included the number of operating units (1, 2, 4), cycle peak pressure (0.5, 1, 2 MPa), and turbo-alternator shaft speed (30,45, 60 kRPM). The design point analysis assumed a fixed turbine inlet temperature (1150 K), compressor inlet temperature (400 K), helium-xenon working-fluid molecular weight (40 g/mol), compressor pressure ratio (2.0), recuperator effectiveness (0.95), and a Sodium-Potassium (NaK) pumped-loop radiator. The design point options were compared on the basis of thermal input power, radiator area, and mass. For a nominal design point with defined Brayton components and radiator area, off-design cases were examined by reducing turbine inlet temperature (as low as 900 K), reducing shaft speed (as low as 50% of nominal), and circulating a percentage (up to 20%) of the compressor exit flow back to the gas cooler. The off-design examination sought approaches to reduce thermal input power without freezing the radiator.

Impact of fluid-structure interaction on direct tumor-targeting in a representative hepatic artery system.

PubMed

Childress, Emily M; Kleinstreuer, Clement

2014-03-01

Direct targeting of solid tumors with chemotherapeutic drugs and/or radioactive microspheres can be a treatment option which minimizes side-effects and reduces cost. Briefly, computational analysis generates particle release maps (PRMs) which visually link upstream particle injection regions in the main artery with associated exit branches, some connected to tumors. The overall goal is to compute patient-specific PRMs realistically, accurately, and cost-effectively, which determines the suitable radial placement of a micro-catheter for optimal particle injection. Focusing in this paper on new steps towards realism and accuracy, the impact of fluid-structure interaction on direct drug-targeting is evaluated, using a representative hepatic artery system with liver tumor as a test bed. Specifically, the effect of arterial wall motion was demonstrated by modeling a two-way fluid-structure interaction analysis with Lagrangian particle tracking in the bifurcating arterial system. Clearly, rapid computational evaluation of optimal catheter location for tumor-targeting in a clinical application is very important. Hence, rigid-wall cases were also compared to the flexible scenario to establish whether PRMs generated when based on simplifying assumptions could provide adequate guidance towards ideal catheter placement. It was found that the best rigid (i.e., time-averaged) geometry is the physiological one that occurs during the diastolic targeting interval.

Method for Making Measurements of the Post-Combustion Residence Time in a Gas Turbine Engine

NASA Technical Reports Server (NTRS)

Miles, Jeffrey H. (Inventor)

2017-01-01

A method of measuring a residence time in a gas-turbine engine is disclosed that includes measuring a combustor pressure signal at a combustor entrance and a turbine exit pressure signal at a turbine exit. The method further includes computing a cross-spectrum function between the combustor pressure signal and the turbine exit pressure signal, calculating a slope of the cross-spectrum function, shifting the turbine exit pressure signal an amount corresponding to a time delay between the measurement of the combustor pressure signal and the turbine exit pressure signal, and recalculating the slope of the cross-spectrum function until the slope reaches zero.

Axial vane-type swirler performance characteristics. M.S. Thesis

NASA Technical Reports Server (NTRS)

Sander, G. F.

1983-01-01

The performance of an axial vane-type swirler was investigated to aid in computer modeling of gas turbine combustor flowfields and in evaluation of turbulence models for swirling confined jet flow. The swirler studied is annular with a hub-to-swirler diameter ratio of 0.25 and ten adjustable vanes of pitch-to-chord ratio 0.68. Measurements of time-mean axial, radial, and tangential velocities were made at the swirler exit plane using a five-hole pitot probe technique with computer data reduction. Nondimensionalized velocities from both radial and azimuthal traverses are tabulated and plotted for a range of swirl vane angles phi from 0 to 70 degrees. A study was done of idealized exit-plane velocity profiles relating the swirl numbers S and S' to the ratio of maximum swirl and axial velocities for each idealized case, and comparing the idealized swirl numbers with ones calculated from measured profiles.

Investigation of scene identification algorithms for radiation budget measurements

NASA Technical Reports Server (NTRS)

Diekmann, F. J.

1986-01-01

The computation of Earth radiation budget from satellite measurements requires the identification of the scene in order to select spectral factors and bidirectional models. A scene identification procedure is developed for AVHRR SW and LW data by using two radiative transfer models. These AVHRR GAC pixels are then attached to corresponding ERBE pixels and the results are sorted into scene identification probability matrices. These scene intercomparisons show that there generally is a higher tendency for underestimation of cloudiness over ocean at high cloud amounts, e.g., mostly cloudy instead of overcast, partly cloudy instead of mostly cloudy, for the ERBE relative to the AVHRR results. Reasons for this are explained. Preliminary estimates of the errors of exitances due to scene misidentification demonstrates the high dependency on the probability matrices. While the longwave error can generally be neglected the shortwave deviations have reached maximum values of more than 12% of the respective exitances.

Self organized spatio-temporal structure within the fractured Vadose Zone: The influence of dynamic overloading at fracture intersections

NASA Astrophysics Data System (ADS)

LaViolette, Randall A.; Glass, Robert J.

2004-09-01

Under low flow conditions (where gravity and capillary forces dominate) within an unsaturated fracture network, fracture intersections act as capillary barriers to integrate flow from above and then release it as a pulse below. Water exiting a fracture intersection is often thought to enter the single connected fracture with the lowest invasion pressure. When the accumulated volume varies between intersections, the smaller volume intersections can be overloaded to cause all of the available fractures exiting an intersection to flow. We included the dynamic overloading process at fracture intersections within our previously discussed model where intersections were modeled as tipping buckets connected within a two-dimensional diamond lattice. With dynamic overloading, the flow behavior transitioned smoothly from diverging to converging flow with increasing overload parameter, as a consequence of a heterogeneous field, and they impose a dynamic structure where additional pathways activate or deactivate in time.

Scale model test results of several STOVL ventral nozzle concepts

NASA Technical Reports Server (NTRS)

Meyer, B. E.; Re, R. J.; Yetter, J. A.

1991-01-01

Short take-off and vertical landing (STOVL) ventral nozzle concepts are investigated by means of a static cold flow scale model at a NASA facility. The internal aerodynamic performance characteristics of the cruise, transition, and vertical lift modes are considered for four ventral nozzle types. The nozzle configurations examined include those with: butterfly-type inner doors and vectoring exit vanes; circumferential inner doors and thrust vectoring vanes; a three-port segmented version with circumferential inner doors; and a two-port segmented version with cylindrical nozzle exit shells. During the testing, internal and external pressure is measured, and the thrust and flow coefficients and resultant vector angles are obtained. The inner door used for ventral nozzle flow control is found to affect performance negatively during the initial phase of transition. The best thrust performance is demonstrated by the two-port segmented ventral nozzle due to the elimination of the inner door.

Experimental evaluation of expendable supersonic nozzle concepts

NASA Technical Reports Server (NTRS)

Baker, V.; Kwon, O.; Vittal, B.; Berrier, B.; Re, R.

1990-01-01

Exhaust nozzles for expendable supersonic turbojet engine missile propulsion systems are required to be simple, short and compact, in addition to having good broad-range thrust-minus-drag performance. A series of convergent-divergent nozzle scale model configurations were designed and wind tunnel tested for a wide range of free stream Mach numbers and nozzle pressure ratios. The models included fixed geometry and simple variable exit area concepts. The experimental and analytical results show that the fixed geometry configurations tested have inferior off-design thrust-minus-drag performance in the transonic Mach range. A simple variable exit area configuration called the Axi-Quad nozzle, combining features of both axisymmetric and two-dimensional convergent-divergent nozzles, performed well over a broad range of operating conditions. Analytical predictions of the flow pattern as well as overall performance of the nozzles, using a fully viscous, compressible CFD code, compared very well with the test data.

Comparison of topical mupirocin and gentamicin in the prevention of peritoneal dialysis-related infections: A systematic review and meta-analysis.

PubMed

Tsai, Chia-Chi; Yang, Po-Sheng; Liu, Chien-Liang; Wu, Chih-Jen; Hsu, Yi-Chiung; Cheng, Shih-Ping

2018-01-01

Topical antibiotics have been shown to reduce exit-site infection and peritonitis. The aim of this study was to compare infection rates between mupirocin and gentamicin. Multiple comprehensive databases were searched systematically to include relevant randomized controlled trials and observational studies. Pooled risk ratios (RRs) and 95% confidence intervals were calculated for the incidences of exit-site infection and peritonitis. Seven studies (mupirocin group n = 458, gentamicin group n = 448) were analyzed for exit-site infection. The risk of gram-positive exit-site infection was similar between the groups. Gram-negative exit-site infection rate was higher in the mupirocin group (RR = 2.125, P = 0.037). Six studies were assessed the peritonitis risk. There was no difference in the gram-positive and -negative peritonitis rate. Topical use of gentamicin is associated with fewer exit-site infections caused by gram-negative organisms. Gentamicin has comparable efficacy to mupirocin for peritonitis and gram-positive exit-site infection. Copyright © 2017 Elsevier Inc. All rights reserved.

Exploring Best Practice Skills to Predict Uncertainties in Venture Capital Investment Decision-Making

NASA Astrophysics Data System (ADS)

Blum, David Arthur

Algae biodiesel is the sole sustainable and abundant transportation fuel source that can replace petrol diesel use; however, high competition and economic uncertainties exist, influencing independent venture capital decision making. Technology, market, management, and government action uncertainties influence competition and economic uncertainties in the venture capital industry. The purpose of this qualitative case study was to identify the best practice skills at IVC firms to predict uncertainty between early and late funding stages. The basis of the study was real options theory, a framework used to evaluate and understand the economic and competition uncertainties inherent in natural resource investment and energy derived from plant-based oils. Data were collected from interviews of 24 venture capital partners based in the United States who invest in algae and other renewable energy solutions. Data were analyzed by coding and theme development interwoven with the conceptual framework. Eight themes emerged: (a) expected returns model, (b) due diligence, (c) invest in specific sectors, (d) reduced uncertainty-late stage, (e) coopetition, (f) portfolio firm relationships, (g) differentiation strategy, and (h) modeling uncertainty and best practice. The most noteworthy finding was that predicting uncertainty at the early stage was impractical; at the expansion and late funding stages, however, predicting uncertainty was possible. The implications of these findings will affect social change by providing independent venture capitalists with best practice skills to increase successful exits, lessen uncertainty, and encourage increased funding of renewable energy firms, contributing to cleaner and healthier communities throughout the United States..

Numerical Evaluation of an Ejector-Enhanced Resonant Pulse Combustor with a Poppet Inlet Valve and a Converging Exhaust Nozzle

NASA Technical Reports Server (NTRS)

Yungster, Shaye; Paxson, Daniel E.; Perkins, Hugh D.

2016-01-01

A computational investigation of a pressure-gain combustor system for gas turbine applications is presented. The system consists of a valved pulse combustor and an ejector, housed within a shroud. The study focuses on two enhancements to previous models, related to the valve and ejector components. First, a new poppet inlet valve system is investigated, replacing the previously used reed valve configuration. Secondly, a new computational approach to approximating the effects of choked turbine inlet guide vanes present immediately downstream of the Ejector-Enhanced Resonant Pulse Combustor (EERPC) is investigated. Instead of specifying a back pressure at the EERPC exit boundary (as was done in previous studies) the new model adds a converging-diverging (CD) nozzle at the exit of the EERPC. The throat area of the CD nozzle can be adjusted to obtain the desired back pressure level and total mass flow rate. The results presented indicate that the new poppet valve configuration performs nearly as well as the original reed valve system, and that the addition of the CD nozzle is an effective method to approximate the exit boundary effects of a turbine present downstream of the EERPC. Furthermore, it is shown that the more acoustically reflective boundary imposed by a nozzle as compared to a constant pressure surface does not significantly affect operation or performance.

Flow visualization and acoustic consequences of the air moving through a static model of the human larynx.

PubMed

Kucinschi, Bogdan R; Scherer, Ronald C; DeWitt, Kenneth J; Ng, Terry T M

2006-06-01

Flow visualization with smoke particles illuminated by a laser sheet was used to obtain a qualitative description of the air flow structures through a dynamically similar 7.5x symmetric static scale model of the human larynx (divergence angle of 10 deg, minimal diameter of 0.04 cm real life). The acoustic level downstream of the vocal folds was measured by using a condenser microphone. False vocal folds (FVFs) were included. In general, the glottal flow was laminar and bistable. The glottal jet curvature increased with flow rate and decreased with the presence of the FVFs. The glottal exit flow for the lowest flow rate showed a curved jet which remained laminar for all geometries. For the higher flow rates, the jet flow patterns exiting the glottis showed a laminar jet core, transitioning to vortical structures, and leading spatially to turbulent dissipation. This structure was shortened and tightened with an increase in flow rate. The narrow FVF gap lengthened the flow structure and reduced jet curvature via acceleration of the flow. These results suggest that laryngeal flow resistance and the complex jet flow structure exiting the glottis are highly affected by flow rate and the presence of the false vocal folds. Acoustic consequences are discussed in terms of the quadrupole- and dipole-type sound sources due to ordered flow structures.

Measuring Years of Inactivity, Years in Retirement, Time to Retirement, and Age at Retirement Within the Markov Model

PubMed Central

SKOOG, GARY R.; CIECKA, JAMES E.

2010-01-01

Retirement-related concepts are treated as random variables within Markov process models that capture multiple labor force entries and exits. The expected number of years spent outside of the labor force, expected years in retirement, and expected age at retirement are computed—all of which are of immense policy interest but have been heretofore reported with less precisely measured proxies. Expected age at retirement varies directly with a person’s age; but even younger people can expect to retire at ages substantially older than those commonly associated with retirement, such as age 60, 62, or 65. Between 1970 and 2003, men allocated most of their increase in life expectancy to increased time in retirement, but women allocated most of their increased life expectancy to labor force activity. Although people can exit and reenter the labor force at older ages, most 65-year-old men who are active in the labor force will not reenter after they eventually exit. At age 65, the probability that those who are inactive will reenter the labor force at some future time is .38 for men and .27 for women. Life expectancy at exact ages is decomposed into the sum of the expected time spent active and inactive in the labor force, and also as the sum of the expected time to labor force separation and time in retirement. PMID:20879680

Full kinetics of CO entry, internal diffusion, and exit in myoglobin from transition-path theory simulations.

PubMed

Yu, Tang-Qing; Lapelosa, Mauro; Vanden-Eijnden, Eric; Abrams, Cameron F

2015-03-04

We use Markovian milestoning molecular dynamics (MD) simulations on a tessellation of the collective variable space for CO localization in myoglobin to estimate the kinetics of entry, exit, and internal site-hopping. The tessellation is determined by analysis of the free-energy surface in that space using transition-path theory (TPT), which provides criteria for defining optimal milestones, allowing short, independent, cell-constrained MD simulations to provide properly weighted kinetic data. We coarse grain the resulting kinetic model at two levels: first, using crystallographically relevant internal cavities and their predicted interconnections and solvent portals; and second, as a three-state side-path scheme inspired by similar models developed from geminate recombination experiments. We show semiquantitative agreement with experiment on entry and exit rates and in the identification of the so-called "histidine gate" at position 64 through which ≈90% of flux between solvent and the distal pocket passes. We also show with six-dimensional calculations that the minimum free-energy pathway of escape through the histidine gate is a "knock-on" mechanism in which motion of the ligand and the gate are sequential and interdependent. In total, these results suggest that such TPT simulations are indeed a promising approach to overcome the practical time-scale limitations of MD to allow reliable estimation of transition mechanisms and rates among metastable states.

Indicators of club management practices and biological measurements of patrons' drug and alcohol use.

PubMed

Byrnes, Hilary F; Miller, Brenda A; Johnson, Mark B; Voas, Robert B

2014-12-01

Electronic music and dance events in nightclubs attract patrons with heavy alcohol/drug use. Public health concerns are raised from risks related to these behaviors. Practices associated with increased risk in these club settings need to be identified. The relationship between club management practices and biological measures of patrons' alcohol/drug use is examined. Observational data from 25 events across six urban clubs were integrated with survey data (N = 738 patrons, 42.8% female) from patrons exiting these events, 2010-2012. Five indicators of club management practices were examined using mixed model regressions: club security, bar crowding, safety signs, serving intoxicated patrons, and isolation. Analyses revealed that serving intoxicated patrons and safety signs were related to substance use. Specifically, serving intoxicated patrons was related to heavy alcohol and drug use at exit, while safety signs were marginally related to less exit drug use. CONCLUSIONS/IMPORTANCE: Findings indicate observable measures in nightclubs provide important indicators for alcohol/drug use, suggesting practices to target. Study strengths include the use of biological measures of substance use on a relatively large scale. Limitations and future directions are discussed.

Oblique impact of dense granular sheets

NASA Astrophysics Data System (ADS)

Ellowitz, Jake; Guttenberg, Nicholas; Jaeger, Heinrich M.; Nagel, Sidney R.; Zhang, Wendy W.

2013-11-01

Motivated by experiments showing impacts of granular jets with non-circular cross sections produce thin ejecta sheets with anisotropic shapes, we study what happens when two sheets containing densely packed, rigid grains traveling at the same speed collide asymmetrically. Discrete particle simulations and a continuum frictional fluid model yield the same steady-state solution of two exit streams emerging from incident streams. When the incident angle Δθ is less than Δθc =120° +/-10° , the exit streams' angles differ from that measured in water sheet experiments. Below Δθc , the exit angles from granular and water sheet impacts agree. This correspondence is surprising because 2D Euler jet impact, the idealization relevant for both situations, is ill posed: a generic Δθ value permits a continuous family of solutions. Our finding that granular and water sheet impacts evolve into the same member of the solution family suggests previous proposals that perturbations such as viscous drag, surface tension or air entrapment select the actual outcome are not correct. Currently at Department of Physics, University of Oregon, Eugene, OR 97403.

Aerodynamics of a Transitioning Turbine Stator Over a Range of Reynolds Numbers

NASA Technical Reports Server (NTRS)

Boyle, R. J.; Lucci, B. L.; Verhoff, V. G.; Camperchioli, W. P.; La, H.

1998-01-01

Midspan aerodynamic measurements for a three vane-four passage linear turbine vane cascade are given. The vane axial chord was 4.45 cm. Surface pressures and loss coefficients were measured at exit Mach numbers of 0.3, 0.7, and 0.9. Reynolds number was varied by a factor of six at the two highest Mach numbers, and by a factor of ten at the lowest Mach number. Measurements were made with and without a turbulence grid. Inlet turbulence intensities were less than I% and greater than IO%. Length scales were also measured. Pressurized air fed the test section, and exited to a low pressure exhaust system. Maximum inlet pressure was two atmospheres. The minimum inlet pressure for an exit Mach number of 0.9 was one-third of an atmosphere, and at a Mach number of 0.3, the minimum pressure was half this value. The purpose of the test was to provide data for verification of turbine vane aerodynamic analyses, especially at low Reynolds numbers. Predictions obtained using a Navier-Stokes analysis with an algebraic turbulence model are also given.

Ducted whistler-mode signals received at two widely spaced locations

NASA Astrophysics Data System (ADS)

Clilverd, M. A.; Thomson, N. R.; Smith, A. J.

1996-06-01

Whistler-mode signals from a single VLF transmitter that have propagated in the same duct, have been observed simultaneously at Faraday, Antarctica (65°S, 64°W) and Dunedin, New Zealand (46°S, 171°E). The signals received have group-delay times that differ in the order of 10 ms, which can be explained by the differences in southern-hemisphere sub-ionospheric propagation time from duct exit region to receiver for the two sites. This difference has been used to determine the location of the duct exit region, with confirmation provided by arrival-bearing information from both sites. The whistler-mode signals typically occur one or two days after geomagnetic activity, with Kpgeq5. The sub-ionospheric-propagation model, LWPC, is used to estimate the whistler-mode power radiated from the duct exit region. These results are then combined with estimated loss values for ionospheric and ducted transmission to investigate the role of wave-particle amplification or absorption. On at least half of the events studied, plasmaspheric amplification of the signals appears to be needed to explain the observed whistler-mode signal strengths.

Python Scripts for Automation of Current-Voltage Testing of Semiconductor Devices (FY17)

DTIC Science & Technology

2017-01-01

ARL-TR-7923 ● JAN 2017 US Army Research Laboratory Python Scripts for Automation of Current- Voltage Testing of Semiconductor...manual device-testing procedures is reduced or eliminated through automation. This technical report includes scripts written in Python , version 2.7, used ...nothing. 3.1.9 Exit Program The script exits the entire program. Line 505, sys.exit(), uses the sys package that comes with Python to exit system

Exiting and Returning to the Parental Home for Boomerang Kids

PubMed Central

Sandberg-Thoma, Sara E.; Snyder, Anastasia R.; Jang, Bohyun Joy

2015-01-01

Young adults commonly exit from and return to the parental home, yet few studies have examined the motivation behind these exits and returns using a life course framework. Using data from the National Longitudinal Survey of Youth 1997, the authors examined associations between mental health problems and economic characteristics and exits from (n = 8,162), and returns to (n = 6,530), the parental home during the transition to adulthood. The average age of the respondents was 24 years. The authors found evidence that mental health and economic characteristics were related to home leaving and returning. Emotional distress was associated with earlier exits from, and returns to, the parental home; alcohol problems were associated with earlier returns to the parental home. The findings regarding economic resources were unexpectedly mixed. Greater economic resources were linked to delayed exits from, and earlier returns to, the parental home. The implications of these findings for young adults are discussed. PMID:26023244

Exiting and Returning to the Parental Home for Boomerang Kids.

PubMed

Sandberg-Thoma, Sara E; Snyder, Anastasia R; Jang, Bohyun Joy

2015-06-01

Young adults commonly exit from and return to the parental home, yet few studies have examined the motivation behind these exits and returns using a life course framework. Using data from the National Longitudinal Survey of Youth 1997, the authors examined associations between mental health problems and economic characteristics and exits from (n = 8,162), and returns to (n = 6,530), the parental home during the transition to adulthood. The average age of the respondents was 24 years. The authors found evidence that mental health and economic characteristics were related to home leaving and returning. Emotional distress was associated with earlier exits from, and returns to, the parental home; alcohol problems were associated with earlier returns to the parental home. The findings regarding economic resources were unexpectedly mixed. Greater economic resources were linked to delayed exits from, and earlier returns to, the parental home. The implications of these findings for young adults are discussed.

Probability of growth of small damage sites on the exit surface of fused silica optics.

PubMed

Negres, Raluca A; Abdulla, Ghaleb M; Cross, David A; Liao, Zhi M; Carr, Christopher W

2012-06-04

Growth of laser damage on fused silica optical components depends on several key parameters including laser fluence, wavelength, pulse duration, and site size. Here we investigate the growth behavior of small damage sites on the exit surface of SiO₂ optics under exposure to tightly controlled laser pulses. Results demonstrate that the onset of damage growth is not governed by a threshold, but is probabilistic in nature and depends both on the current size of a damage site and the laser fluence to which it is exposed. We also develop models for use in growth prediction. In addition, we show that laser exposure history also influences the behavior of individual sites.

Do changes in the labour market take families out of poverty? Determinants of exiting poverty in Brazilian metropolitan regions.

PubMed

Machado, Ana Flavia; Ribas, Rafael Perez Ribas

2010-01-01

Using survival models, we test whether short-term changes in the labour market affect poverty duration. Data are from the Brazilian Monthly Employment Survey. Such a monthly dataset permits more accurate estimations of events than using annual data, but its panel follows households for a short period. Then methods that control for both right- and left-censoring should be used. The results are as follows: households with zero income are not those with the lowest chances of exiting; changes in aggregate unemployment do not affect poverty duration; and increasing wages in the informal sector has a negative effect on poverty duration.

The relationship between group size, intoxication and continuing to drink after bar attendance.

PubMed

Reed, Mark B; Clapp, John D; Martell, Brandi; Hidalgo-Sotelo, Alexandra

2013-11-01

The present study was undertaken to explore multilevel determinants of planning to continue to drink alcohol after leaving public drinking events. We assessed whether individual-level factors, group-related factors, or event-level bar characteristics were associated with post-bar drinking. We recruited a total of 642 participants from 30 participating bars in urban Southern California. Groups who arrived to patron a bar were interviewed upon their entrance and exit. Given data nesting, we employed a multilevel modeling approach to data analysis. More than one-third (40%) of our sample reported the intention to continue drinking as they exited the bar. Results of our multilevel model indicated eight individual-level variables significantly associated with intending to continue to drink. Time of night moderated the relationship between BrAC change and intentions to continue to drink. Although none of the group factors were significant in our model, a significant cross-level interaction between BrAC change and number of group members indicated the effect of intoxication on planning to continue to drink increases as group members increase. At the bar level, the presence of temporary bars and server offers of non-alcoholic drinks significantly decreased intentions to continue to drink. Given the large percentage of participants who reported the intention to continue drinking after exiting a bar, this study draws attention to the fact that field studies of drinking behavior may assess drinking mid-event rather than at the end of a drinking event. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Human Factors in Web-Authentication

DTIC Science & Technology

2009-02-06

47 5.2.7 Debriefing and exit survey . . . . . . . . . . . . . . . . . . . . . . 48 5.2.8 Ethics...Deployability analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 7.4.1 An SSL server survey ...102 9 Conclusion 104 Bibliography 106 A User study exit survey questions 121 B User study exit survey

Method for Making Measurements of the Post-Combustion Residence Time in a Gas Turbine Engine

NASA Technical Reports Server (NTRS)

Miles, Jeffrey H (Inventor)

2015-01-01

A system and method of measuring a residence time in a gas-turbine engine is provided, whereby the method includes placing pressure sensors at a combustor entrance and at a turbine exit of the gas-turbine engine and measuring a combustor pressure at the combustor entrance and a turbine exit pressure at the turbine exit. The method further includes computing cross-spectrum functions between a combustor pressure sensor signal from the measured combustor pressure and a turbine exit pressure sensor signal from the measured turbine exit pressure, applying a linear curve fit to the cross-spectrum functions, and computing a post-combustion residence time from the linear curve fit.

HAZARDOUS WASTE IDENTIFICATION

EPA Science Inventory

This research is in direct support of the regulatory reform efforts under the Hazarous Waste Identification (HWIR) and is related to the development of national "exit levels" based on sound scientific data and models. Research focuses on developing a systems approach to modelin...

Flow and clog in a silo with oscillating exit

NASA Astrophysics Data System (ADS)

To, Kiwing; Tai, Hsiang-Ting

2017-09-01

When grains flow out of a silo, flow rate W increases with exit size D . If D is too small, an arch may form and the flow may be blocked at the exit. To recover from clogging, the arch has to be destroyed. Here we construct a two-dimensional silo with movable exit and study the effects of exit oscillation (with amplitude A and frequency f ) on flow rate, clogging, and unclogging of grains through the exit. We find that, if exit oscillates, W remains finite even when D (measured in unit of grain diameter) is only slightly larger than one. Surprisingly, while W increases with oscillation strength Γ ≡4 π2A f2 as expected at small D , W decreases with Γ when D ≥5 due to induced random motion of the grains at the exit. When D is small and oscillation speed v ≡2 π A f is slow, temporary clogging events cause the grains to flow intermittently. In this regime, W depends only on v —a feature consistent to a simple arch breaking mechanism, and the phase boundary of intermittent flow in the D -v plane is consistent to either a power law: D ∝v-7 or an exponential form: D ∝e-D /0.55 . Furthermore, the flow time statistic is Poissonian whereas the recovery time statistic follows a power-law distribution.

Study of Double-Weighted Graph Model and Optimal Path Planning for Tourist Scenic Area Oriented Intelligent Tour Guide

NASA Astrophysics Data System (ADS)

Shi, Y.; Long, Y.; Wi, X. L.

2014-04-01

When tourists visiting multiple tourist scenic spots, the travel line is usually the most effective road network according to the actual tour process, and maybe the travel line is different from planned travel line. For in the field of navigation, a proposed travel line is normally generated automatically by path planning algorithm, considering the scenic spots' positions and road networks. But when a scenic spot have a certain area and have multiple entrances or exits, the traditional described mechanism of single point coordinates is difficult to reflect these own structural features. In order to solve this problem, this paper focuses on the influence on the process of path planning caused by scenic spots' own structural features such as multiple entrances or exits, and then proposes a doubleweighted Graph Model, for the weight of both vertexes and edges of proposed Model can be selected dynamically. And then discusses the model building method, and the optimal path planning algorithm based on Dijkstra algorithm and Prim algorithm. Experimental results show that the optimal planned travel line derived from the proposed model and algorithm is more reasonable, and the travelling order and distance would be further optimized.

Attentional control of associative learning--a possible role of the central cholinergic system.

PubMed

Pauli, Wolfgang M; O'Reilly, Randall C

2008-04-02

How does attention interact with learning? Kruschke [Kruschke, J.K. (2001). Toward a unified Model of Attention in Associative Learning. J. Math. Psychol. 45, 812-863.] proposed a model (EXIT) that captures Mackintosh's [Mackintosh, N.J. (1975). A theory of attention: Variations in the associability of stimuli with reinforcement. Psychological Review, 82(4), 276-298.] framework for attentional modulation of associative learning. We developed a computational model that showed analogous interactions between selective attention and associative learning, but is significantly simplified and, in contrast to EXIT, is motivated by neurophysiological findings. Competition among input representations in the internal representation layer, which increases the contrast between stimuli, is critical for simulating these interactions in human behavior. Furthermore, this competition is modulated in a way that might be consistent with the phasic activation of the central cholinergic system, which modulates activity in sensory cortices. Specifically, phasic increases in acetylcholine can cause increased excitability of both pyramidal excitatory neurons in cortical layers II/III and cortical GABAergic inhibitory interneurons targeting the same pyramidal neurons. These effects result in increased attentional contrast in our model. This model thus represents an initial attempt to link human attentional learning data with underlying neural substrates.

Attentional control of associative learning—A possible role of the central cholinergic system

PubMed Central

Pauli, Wolfgang M.; O'Reilly, Randall C.

2010-01-01

How does attention interact with learning? Kruschke [Kruschke, J.K. (2001). Toward a unified Model of Attention in Associative Learning. J. Math. Psychol. 45, 812–863.] proposed a model (EXIT) that captures Mackintosh's [Mackintosh, N.J. (1975). A theory of attention: Variations in the associability of stimuli with reinforcement. Psychological Review, 82(4), 276–298.] framework for attentional modulation of associative learning. We developed a computational model that showed analogous interactions between selective attention and associative learning, but is significantly simplified and, in contrast to EXIT, is motivated by neurophysiological findings. Competition among input representations in the internal representation layer, which increases the contrast between stimuli, is critical for simulating these interactions in human behavior. Furthermore, this competition is modulated in a way that might be consistent with the phasic activation of the central cholinergic system, which modulates activity in sensory cortices. Specifically, phasic increases in acetylcholine can cause increased excitability of both pyramidal excitatory neurons in cortical layers II/III and cortical GABAergic inhibitory interneurons targeting the same pyramidal neurons. These effects result in increased attentional contrast in our model. This model thus represents an initial attempt to link human attentional learning data with underlying neural substrates. PMID:17870060

Promoting recovery via an integrated model of care to deliver a bed-based, mental health prevention and recovery centre.

PubMed

Lee, Stuart J; Collister, Laura; Stafrace, Simon; Crowther, Elizabeth; Kroschel, Jon; Kulkarni, Jayashri

2014-10-01

This research was conducted in order to explore the experience of care and outcomes for people entering a bed-based step-up/step-down Prevention and Recovery Centre (PARC). An audit of files for PARC participants in 2010 collected demographic (age, gender, and marital, housing, employment and education/training status) and clinical measures (length of stay, entry and exit outcome measures, psychiatric hospital use). Participants were also invited to a feedback group to discuss their PARC experience. In 2010, 118 people entered PARC. Most were single and unemployed and 35% were in temporary housing or homeless. In the six months following PARC exit, participants spent significantly less time in psychiatric hospital than in the six months prior to entry (p<0.001). Significant reductions in clinician-rated difficulties were documented at exit (p<0.001). For 40 episodes of care with self-report measures at entry and exit, significant reductions in difficulties with relating to self/others (p=0.004), daily living/role functioning (p=0.006), and depression/anxiety (p=0.019) were seen. Twelve participants attended a feedback group. Positive aspects of PARC included: supportive and caring staff; help with practical issues or community access; therapeutic activities and learning about health; and socialization opportunities. A step-up/step-down PARC can facilitate recovery for people with mental illness through promoting independence and illness self-management. © The Royal Australian and New Zealand College of Psychiatrists 2014.

To fish or not to fish: factors at multiple scales affecting artisanal fishers' readiness to exit a declining fishery.

PubMed

Daw, Tim M; Cinner, Joshua E; McClanahan, Timothy R; Brown, Katrina; Stead, Selina M; Graham, Nicholas A J; Maina, Joseph

2012-01-01

Globally, fisheries are challenged by the combined impacts of overfishing, degradation of ecosystems and impacts of climate change, while fisheries livelihoods are further pressured by conservation policy imperatives. Fishers' adaptive responses to these pressures, such as exiting from a fishery to pursue alternative livelihoods, determine their own vulnerability, as well as the potential for reducing fishing effort and sustaining fisheries. The willingness and ability to make particular adaptations in response to change, such as exiting from a declining fishery, is influenced by economic, cultural and institutional factors operating at scales from individual fishers to national economies. Previous studies of exit from fisheries at single or few sites, offer limited insight into the relative importance of individual and larger-scale social and economic factors. We asked 599 fishers how they would respond to hypothetical scenarios of catch declines in 28 sites in five western Indian Ocean countries. We investigated how socioeconomic variables at the individual-, household- and site-scale affected whether they would exit fisheries. Site-level factors had the greatest influence on readiness to exit, but these relationships were contrary to common predictions. Specifically, higher levels of infrastructure development and economic vitality - expected to promote exit from fisheries - were associated with less readiness to exit. This may be due to site level histories of exit from fisheries, greater specialisation of fishing households, or higher rewards from fishing in more economically developed sites due to technology, market access, catch value and government subsidies. At the individual and household scale, fishers from households with more livelihood activities, and fishers with lower catch value were more willing to exit. These results demonstrate empirically how adaptive responses to change are influenced by factors at multiple scales, and highlight the importance of understanding natural resource-based livelihoods in the context of the wider economy and society.

Modeling Hidden Circuits: An Authentic Research Experience in One Lab Period

ERIC Educational Resources Information Center

Moore, J. Christopher; Rubbo, Louis J.

2016-01-01

Two wires exit a black box that has three exposed light bulbs connected together in an unknown configuration. The task for students is to determine the circuit configuration without opening the box. In the activity described in this paper, we navigate students through the process of making models, developing and conducting experiments that can…

Revisit the faster-is-slower effect for an exit at a corner

NASA Astrophysics Data System (ADS)

Chen, Jun Min; Lin, Peng; Wu, Fan Yu; Li Gao, Dong; Wang, Guo Yuan

2018-02-01

The faster-is-slower effect (FIS), which means that crowd at a high enough velocity could significantly increase the evacuation time to escape through an exit, is an interesting phenomenon in pedestrian dynamics. Such phenomenon had been studied widely and has been experimentally verified in different systems of discrete particles flowing through a centre exit. To experimentally validate this phenomenon by using people under high pressure is difficult due to ethical issues. A mouse, similar to a human, is a kind of self-driven and soft body creature with competitive behaviour under stressed conditions. Therefore, mice are used to escape through an exit at a corner. A number of repeated tests are conducted and the average escape time per mouse at different levels of stimulus are analysed. The escape times do not increase obviously with the level of stimulus for the corner exit, which is contrary to the experiment with the center exit. The experimental results show that the FIS effect is not necessary a universal law for any discrete system. The observation could help the design of buildings by relocating their exits to the corner in rooms to avoid the formation of FIS effect.

Design of ocular for optical sight with long exit pupil distance

NASA Astrophysics Data System (ADS)

Zhu, Zhongyao; Li, Yuyao; Tian, Ailing

2017-02-01

In order to solve the injury of optical sight to shooters, which is produced by recoil for using artillery or firearms, and the usage problems of shooters' eye mask, headband and gas mask, the ocular with long exit pupil distance has been designed based on optical sighting system. The optical properties and aberration characteristics of ocular with long exit pupil distance has been analyzed, the structural style with positive-positive-negative three lens groups has been put forward. According to the aberration theory and the isoplanatic image formation principle, the focal power assignment expression has been deduced by adopting analytical method. By using of optical design software ZEMAX, the ocular with long exit pupil distance has been designed, the focal length of system is 20mm, the exit pupil diameter is 4mm, the field angle is 40°, the distance of exit pupil is 41mm, and the relative eye relief is greater than 2. The design results show if this method has been adopted, the transfer functions of each field are all greater than 0.15 when the ocular with long exit pupil distance locates on 45lp/mm, which can meet the use requirements of visual optical instruments.

The exit interview as a proxy measure of malaria case management practice: sensitivity and specificity relative to direct observation.

PubMed

Pulford, Justin; Siba, Peter M; Mueller, Ivo; Hetzel, Manuel W

2014-12-03

This paper aims to assess the sensitivity and specificity of exit interviews as a measure of malaria case management practice as compared to direct observation. The malaria case management of 1654 febrile patients attending 110 health facilities from across Papua New Guinea was directly observed by a trained research officer as part of a repeat cross sectional survey. Patient recall of 5 forms of clinical advice and 5 forms of clinical action were then assessed at service exit and statistical analyses on matched observation/exit interview data conducted. The sensitivity of exit interviews with respect to clinical advice ranged from 36.2% to 96.4% and specificity from 53.5% to 98.6%. With respect to clinical actions, sensitivity of the exit interviews ranged from 83.9% to 98.3% and specificity from 70.6% to 98.1%. The exit interview appears to be a valid measure of objective malaria case management practices such as the completion of a diagnostic test or the provision of antimalarial medication, but may be a less valid measure of low frequency, subjective practices such as the provision of malaria prevention advice.

SU-F-T-229: A Novel Method for EPID-Based In-Vivo Exit Dose Verification for Intensity Modulated Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Z; Wang, J; Peng, J

Purpose: Electronic portal imaging device (EPID) can be used to acquire a two-dimensional exit dose distribution during treatment delivery, thus allowing the in-vivo verification of the dose delivery through a comparison of measured portal images to predicted portal dose images (PDI). The aim of this study was to present a novel method to easily and accurately predict PDI, and to establish an EPID-based in-vivo dose verification method during IMRT treatments. Methods: We developed a model to determine the predicted portal dose at the same plane of the EPID detector location. The Varian EPID (aS1000) positions at 150cm source-to-detector-distance (SDD), andmore » can be used to acquire in-vivo exit dose using Portal Dosimetry (PD) function. Our model was generated to make an equivalent water thickness represent the buildup plate of EPID. The exit dose at extend SDD plane with patient CT data in the beam can be calculated as the predicted PDI in the treatment planning system (TPS). After that, the PDI was converted to the fluence at SDD of 150cm using the inverse square law coded in MATLAB. Five head-and-neck and prostate IMRT patient plans contain 32 fields were investigated to evaluate the feasibility of this new method. The measured EPID image was compared with PDI using the gamma analysis. Results: The average results for cumulative dose comparison were 81.9% and 91.6% for 3%, 3mm and 4%, 4mm gamma criteria, respectively. Results indicate that the patient transit dosimetry predicted algorithm compares well with EPID measured PD doses for test situations. Conclusion: Our new method can be used as an easy and feasible tool for online EPID-based in-vivo dose delivery verification for IMRT treatments. It can be implemented for fast detecting those obvious treatment delivery errors for individual field and patient quality assurance.« less

Supersonic/Hypersonic Correlations for In-Cavity Transition and Heating Augmentation

NASA Technical Reports Server (NTRS)

Everhart, Joel L.

2011-01-01

Laminar-entry cavity heating data with a non-laminar boundary layer exit flow have been retrieved from the database developed at Mach 6 and 10 in air on large flat plate models for the Space Shuttle Return-To-Flight Program. Building on previously published fully laminar and fully turbulent analysis methods, new descriptive correlations of the in-cavity floor-averaged heating and endwall maximum heating have been developed for transitional-to-turbulent exit flow. These new local-cavity correlations provide the expected flow and geometry conditions for transition onset; they provide the incremental heating augmentation induced by transitional flow; and, they provide the transitional-to-turbulent exit cavity length. Furthermore, they provide an upper application limit for the previously developed fully-laminar heating correlations. An example is provided that demonstrates simplicity of application. Heating augmentation factors of 12 and 3 above the fully laminar values are shown to exist on the cavity floor and endwall, respectively, if the flow exits in fully tripped-to-turbulent boundary layer state. Cavity floor heating data in geometries installed on the windward surface of 0.075-scale Shuttle wind tunnel models have also been retrieved from the boundary layer transition database developed for the Return-To-Flight Program. These data were independently acquired at Mach 6 and Mach 10 in air, and at Mach 6 in CF4. The correlation parameters for the floor-averaged heating have been developed and they offer an exceptionally positive comparison to previously developed laminar-cavity heating correlations. Non-laminar increments have been extracted from the Shuttle data and they fall on the newly developed transitional in-cavity correlations, and they are bounded by the 95% correlation prediction limits. Because the ratio of specific heats changes along the re-entry trajectory, turning angle into a cavity and boundary layer flow properties may be affected, raising concerns regarding the application validity of the heating augmentation predictions.

Tritium in Exit Signs | RadTown USA | US EPA

EPA Pesticide Factsheets

2018-05-01

Many exit signs contain tritium to light the sign without batteries or electricity, which allows it to remain lit if the power goes out. Tritium is most dangerous when it is inhaled or swallowed. Never tamper with a tritium exit sign.

Engineering Development Tests Airdrop Controlled Exit System (ACES)

DTIC Science & Technology

1980-09-01

AIRDROP CONTROLLED EXIT SYSTEM ( ACES ) RECOVERY PARACHUTES TELEMETERING DATA 20. D5TFAC c• Cat •u•u am revers e• ift n•ceesafy ad Ide•lityf by block...rTECHNICAL REPORT , NATICK /TR-82 /017 f C’n Engineering Development Tests Airdropý Controlled Exit System ( ACES ) COPY CLV40ble to DTIC doe’ io C...and,50.,,,10) s. TYPE OF REPORT A PERIOn COVEnEo Test Report ENCINEERTNG DEVELOPMENT TESTS Oct 79 - Apr 80 AIRDROP CONTROLLED EXIT SYSTEM ( ACES ) 6

Method of forming magnesium alloy sheets

DOEpatents

Mualidharan, Govindarajan; Muth, Thomas R.; Harper, David C.

2015-12-22

A machine for asymmetric rolling of a work-piece includes pair of rollers disposed in an arrangement to apply opposing, asymmetric rolling forces to roll a work-piece therebetween, wherein a surface of the work-piece is rolled faster than an opposite surface of the work-piece; and an exit constraint die rigidly disposed adjacent an exit side of the pair of rollers so that, as the work-piece exits the pair of rollers, the work-piece contacts the exit constraint die to constrain curling of the work-piece.

Jet engine nozzle exit configurations and associated systems and methods

NASA Technical Reports Server (NTRS)

Mengle, Vinod G. (Inventor)

2011-01-01

Nozzle exit configurations and associated systems and methods are disclosed. An aircraft system in accordance with one embodiment includes a jet engine exhaust nozzle having an internal flow surface and an exit aperture, with the exit aperture having a perimeter that includes multiple projections extending in an aft direction. Aft portions of individual neighboring projections are spaced apart from each other by a gap, and a geometric feature of the multiple can change in a monotonic manner along at least a portion of the perimeter.

Jet Engine Nozzle Exit Configurations and Associated Systems and Methods

NASA Technical Reports Server (NTRS)

Mengle, Vinod G. (Inventor)

2013-01-01

Nozzle exit configurations and associated systems and methods are disclosed. An aircraft system in accordance with one embodiment includes a jet engine exhaust nozzle having an internal flow surface and an exit aperture, with the exit aperture having a perimeter that includes multiple projections extending in an aft direction. Aft portions of individual neighboring projections are spaced apart from each other by a gap, and a geometric feature of the multiple can change in a monotonic manner along at least a portion of the perimeter.

Shored gunshot wound of exit. A phenomenon with identity crisis.

PubMed

Aguilar, J C

1983-09-01

Shored gunshot wound of exit is produced when the outstretched skin is impaled, sandwiched, and crushed between the outgoing bullet and the unyielding object over the exit site, thus leaving an abrasion collar on the wound margin. Proper coaptation of the wound margin is impossible because of the loss of skin just like those observed in entrance wounds. In contrast to the entrance wound, the supported exit wound shows a scalloped or punched-out abrasion collar and sharply contoured skin in between the radiating skin lacerations marginating the abrasion (Fig. 1). Should gunpowder be observed around the exit site, it is often unevenly distributed, and is not associated with searing, gunpowder stippled abrasion, tatooing, and deposition of soot.

Identification and Comprehension of Symbolic Exit Signs for Small Transport-Category Airplanes

DTIC Science & Technology

2014-02-01

8 Phase Two: Self -illuminated Exit Signs...11 Self -illuminated Exit Sign Comprehension ---------------------------------------------------------------------- 12 Automatic...other sign parameters such as stroke width to height, contrast ratios, and self -illumination, fall within those recommended by 14 CFR 25.812(b)(2

Aircraft evacuations through type-III exits II : effects of individual subject differences.

DOT National Transportation Integrated Search

1995-08-01

Simulated emergency egress from Type III over-wing exits was studied to support regulatory action by the FAA. Passageway width from the aircraft center aisle to the Type-III exit was the major variable of interest; effects of individual subject attri...

Symmetry associated with symmetry break: Revisiting ants and humans escaping from multiple-exit rooms

NASA Astrophysics Data System (ADS)

Ji, Q.; Xin, C.; Tang, S. X.; Huang, J. P.

2018-02-01

Crowd panic has incurred massive injuries or deaths throughout the world, and thus understanding it is particularly important. It is now a common knowledge that crowd panic induces "symmetry break" in which some exits are jammed while others are underutilized. Amazingly, here we show, by experiment, simulation and theory, that a class of symmetry patterns come to appear for ants and humans escaping from multiple-exit rooms while the symmetry break exists. Our symmetry pattern is described by the fact that the ratio between the ensemble-averaging numbers of ants or humans escaping from different exits is equal to the ratio between the widths of the exits. The mechanism lies in the effect of heterogeneous preferences of agents with limited information for achieving the Nash equilibrium. This work offers new insights into how to improve public safety because large public areas are always equipped with multiple exits, and it also brings an ensemble-averaging method for seeking symmetry associated with symmetry breaking.

Partial polarizer filter

NASA Technical Reports Server (NTRS)

Title, A. M. (Inventor)

1978-01-01

A birefringent filter module comprises, in seriatum. (1) an entrance polarizer, (2) a first birefringent crystal responsive to optical energy exiting the entrance polarizer, (3) a partial polarizer responsive to optical energy exiting the first polarizer, (4) a second birefringent crystal responsive to optical energy exiting the partial polarizer, and (5) an exit polarizer. The first and second birefringent crystals have fast axes disposed + or -45 deg from the high transmitivity direction of the partial polarizer. Preferably, the second crystal has a length 1/2 that of the first crystal and the high transmitivity direction of the partial polarizer is nine times as great as the low transmitivity direction. To provide tuning, the polarizations of the energy entering the first crystal and leaving the second crystal are varied by either rotating the entrance and exit polarizers, or by sandwiching the entrance and exit polarizers between pairs of half wave plates that are rotated relative to the polarizers. A plurality of the filter modules may be cascaded.

Dropped out or pushed out? Insurance market exit and provider market power in Medicare Advantage.

PubMed

Pelech, Daria

2017-01-01

This paper explores how provider and insurer market power affect which markets an insurer chooses to operate in. A 2011 policy change required that certain private insurance plans in Medicare form provider networks de novo; in response, insurers cancelled two-thirds of the affected plans. Using detailed data on pre-policy provider and insurer market structure, I compare markets where insurers built networks to those they exited. Overall, insurers in the most concentrated hospital and physician markets were 9 and 13 percentage points more likely to exit, respectively, than those in the least concentrated markets. Conversely, insurers with more market power were less likely to exit than those with less, and an insurer's market power had the largest effect on exit in concentrated hospital markets. These findings suggest that concentrated provider markets contribute to insurer exit and that insurers with less market power have more difficulty surviving in concentrated provider markets. Published by Elsevier B.V.

The use of the exit interview to reduce turnover amongst healthcare professionals.

PubMed

Flint, Anndrea; Webster, Joan

2011-01-19

Exit interviews are widely used in healthcare organisations to identify reasons for staff attrition, yet their usefulness in limiting turnover is unclear. To determine the effectiveness of various exit interview strategies in decreasing turnover rates amongst healthcare professionals. We used a comprehensive search strategy including an electronic search of the following databases: DARE, CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, ERIC (search date: 7 September 2010) and EPOC Specialised Register (search date: 30 September 2009). We also screened the reference lists of included studies and relevant reviews. Randomised controlled trials, controlled clinical trials, controlled before and after studies and interrupted time series studies comparing turnover rates between healthcare professionals who had undergone one form of exit interview with another form of exit interview or with no interview. Two review authors independently assessed trial quality and extracted data. The search identified 1560 citations of which we considered 19 potentially relevant. The two authors independently reviewed the abstracts of these studies and retrieved the full texts of eight studies. We excluded all eight following independent assessment. They were either interviews, commentaries on how to do an exit interview or descriptive studies about reasons for leaving. We found no trials that matched our inclusion criteria. Evidence about the effectiveness of exit interviews to reduce turnover is currently not available. However, exit interviews may provide useful information about the work environment which, in turn, may be useful in the development of interventions to reduce turnover.

The Differential Roles of Budding Yeast Tem1p, Cdc15p, and Bub2p Protein Dynamics in Mitotic ExitD⃞V⃞

PubMed Central

Molk, Jeffrey N.; Schuyler, Scott C.; Liu, Jenny Y.; Evans, James G.; Salmon, E. D.; Pellman, David; Bloom, Kerry

2004-01-01

In the budding yeast Saccharomyces cerevisiae the mitotic spindle must be positioned along the mother-bud axis to activate the mitotic exit network (MEN) in anaphase. To examine MEN proteins during mitotic exit, we imaged the MEN activators Tem1p and Cdc15p and the MEN regulator Bub2p in vivo. Quantitative live cell fluorescence microscopy demonstrated the spindle pole body that segregated into the daughter cell (dSPB) signaled mitotic exit upon penetration into the bud. Activation of mitotic exit was associated with an increased abundance of Tem1p-GFP and the localization of Cdc15p-GFP on the dSPB. In contrast, Bub2p-GFP fluorescence intensity decreased in mid-to-late anaphase on the dSPB. Therefore, MEN protein localization fluctuates to switch from Bub2p inhibition of mitotic exit to Cdc15p activation of mitotic exit. The mechanism that elevates Tem1p-GFP abundance in anaphase is specific to dSPB penetration into the bud and Dhc1p and Lte1p promote Tem1p-GFP localization. Finally, fluorescence recovery after photobleaching (FRAP) measurements revealed Tem1p-GFP is dynamic at the dSPB in late anaphase. These data suggest spindle pole penetration into the bud activates mitotic exit, resulting in Tem1p and Cdc15p persistence at the dSPB to initiate the MEN signal cascade. PMID:14718561

Bacterial colonization patterns in daily chlorhexidine care at the exit site in peritoneal dialysis patients-A prospective, randomized controlled trial.

PubMed

Wang, Hsi-Hao; Hung, Shih-Yuan; Chang, Min-Yu; Lee, Yi-Che; Lin, Hsiu-Fang; Lin, Tsun-Mei; Yang, Su-Pen; Lin, Hsi-Hsun; Yang, Su-Ching; Wang, Jiun-Ling

2017-01-01

Bacterial colonization patterns in daily chlorhexidine care at the exit site in peritoneal dialysis (PD) patients were not known. We performed a prospective, randomized controlled trial enrolling 89 PD patients. After stratification by initial Staphylococcus aureus (SA) carrier status, patients were randomly assigned to receive daily 4% chlorhexidine care (intervention group) or normal saline (control group) at the exit site. Monthly, we cultured bacteria from the exit site and nasal swabs for 1 year. The SA colonization rates at exit site at 6 and 12 months were significantly lower in the intervention group than the control group (5.0% vs. 22.9%, p = 0.023 and 8.6% vs. 28.1%, p = 0.037 for 6 and 12 months, respectively). The Methicillin-resistant SA (MRSA) colonization rate at exit site at 6 months was similar (5.7% vs. 2.5%,p = 0.596) in control and intervention group, but significantly lower in the intervention group than the control group at exit site at 12months (0% vs. 12.5%, p = 0.047). The gram-negative bacilli (GNB) colonization rates were similar between the intervention and control groups at 6 and 12 months. Genotyping of all MRSA isolates showed ST (sequence type) 59 was the most predominant clone. In conclusion, chlorhexidine care at the exit site in PD patients may be a good strategy for SA and MRSA decolonization. ClinicalTrials.gov NCT02446158.

Minimal formulation of the linear spatial analysis of capillary jets: Validity of the two-mode approach

NASA Astrophysics Data System (ADS)

González, H.; Vazquez, P. A.; García, F. J.; Guerrero, J.

2018-04-01

A rigorous and complete formulation of the linear evolution of harmonically stimulated capillary jets should include infinitely many spatial modes to account for arbitrary exit conditions [J. Guerrero et al., J. Fluid Mech. 702, 354 (2012), 10.1017/jfm.2012.182]. However, it is not rare to find works in which only the downstream capillary dominant mode, the sole unstable one, is retained, with amplitude determined by the jet deformation at the exit. This procedure constitutes an oversimplification, unable to handle a flow rate perturbation without jet deformation at the exit (the most usual conditions). In spite of its decaying behavior, the other capillary mode (subdominant) must be included in what can be called a "minimal linear formulation." Deformation and mean axial velocity amplitudes at the jet exit are the two relevant parameters to simultaneously find the amplitudes of both capillary modes. Only once these amplitudes are found, the calculation of the breakup length may be eventually simplified by disregarding the subdominant mode. Simple recipes are provided for predicting the breakup length, which are checked against our own numerical simulations. The agreement is better than in previous attempts in the literature. Besides, the limits of validity of the linear formulation are explored in terms of the exit velocity amplitude, the wave number, the Weber number, and the Ohnesorge number. Including the subdominant mode extends the range of amplitudes for which the linear model gives accurate predictions, the criterion for keeping this mode being that the breakup time must be shorter than a given formula. It has been generally assumed that the shortest intact length happens for the stimulation frequency with the highest growth rate. However, we show that this correlation is not strict because the amplitude of the dominant mode has a role in the breakup process and it depends on the stimulation frequency.

Exit and Voice: Organizational Loyalty and Dispute Resolution Strategies

ERIC Educational Resources Information Center

Hoffmann, Elizabeth A.

2006-01-01

This study compares workplace dispute resolution strategies (exit, voice and toleration) in matched pairs of conventional and worker-owned cooperative organizations operating in three industries--coal mining, taxicab driving and organic food distribution. Building on Hirschman's classic exit, voice and loyalty thesis, this research demonstrates…

14 CFR Appendix D to Part 29 - Criteria for Demonstration of Emergency Evacuation Procedures Under § 29.803

Code of Federal Regulations, 2011 CFR

2011-01-01

... exit and each internal door or curtain must be in the takeoff configuration. (g) Each crewmember must... outside the exits to indicate fire or other reasons why they are unusable. The exits to be used must be...

77 FR 153 - Passenger Train Emergency Systems II

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-03

... emergency exits and the path to the nearest exit in the dark. Existing signage inside some passenger... and markings in the dark. Debriefing and Critique FRA is proposing a modification to the existing... standard satisfactorily addresses matters related to emergency signage, exit path marking, and egress...

14 CFR 121.585 - Exit seating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... perform the functions listed in paragraph (d) of this section or a passenger requests a non-exit seat, the... holder shall determine, to the extent necessary to perform the applicable functions of paragraph (d) of... passenger exit seating determinations required by this paragraph in a non-discriminatory manner consistent...

14 CFR 121.585 - Exit seating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... perform the functions listed in paragraph (d) of this section or a passenger requests a non-exit seat, the... holder shall determine, to the extent necessary to perform the applicable functions of paragraph (d) of... passenger exit seating determinations required by this paragraph in a non-discriminatory manner consistent...

14 CFR 121.585 - Exit seating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... perform the functions listed in paragraph (d) of this section or a passenger requests a non-exit seat, the... holder shall determine, to the extent necessary to perform the applicable functions of paragraph (d) of... passenger exit seating determinations required by this paragraph in a non-discriminatory manner consistent...

14 CFR 121.585 - Exit seating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... perform the functions listed in paragraph (d) of this section or a passenger requests a non-exit seat, the... holder shall determine, to the extent necessary to perform the applicable functions of paragraph (d) of... passenger exit seating determinations required by this paragraph in a non-discriminatory manner consistent...

14 CFR 121.585 - Exit seating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... perform the functions listed in paragraph (d) of this section or a passenger requests a non-exit seat, the... holder shall determine, to the extent necessary to perform the applicable functions of paragraph (d) of... passenger exit seating determinations required by this paragraph in a non-discriminatory manner consistent...

Similarity laws of lunar and terrestrial volcanic flows

NASA Technical Reports Server (NTRS)

Pai, S. I.; Hsu, Y.; Okeefe, J. A.

1977-01-01

A mathematical model of a one dimensional, steady duct flow of a mixture of a gas and small solid particles (rock) was analyzed and applied to the lunar and the terrestrial volcanic flows under geometrically and dynamically similar conditions. Numerical results for the equilibrium two phase flows of lunar and terrestrial volcanoes under similar conditions are presented. The study indicates that: (1) the lunar crater is much larger than the corresponding terrestrial crater; (2) the exit velocity from the lunar volcanic flow may be higher than the lunar escape velocity but the exit velocity of terrestrial volcanic flow is much less than that of the lunar case; and (3) the thermal effects on the lunar volcanic flow are much larger than those of the terrestrial case.

Heat transfer rate and film cooling effectiveness measurements in a transient cascade

NASA Astrophysics Data System (ADS)

Schultz, D. L.; Oldfield, M. L. G.; Jones, T. V.

1980-09-01

A transient cascade useful for heat transfer rate measurements is briefly described. The facility employs a free piston which compresses the test gas to temperatures around 450 K and pressures of about 3.5 to 7.5 Atm. The model is initially at room temperature and it is necessary to attain the correct gas to wall temperature ratio. The exit Mach number is set by the inlet total pressure and the pressure in the exit dump tank. Thin film heat transfer gauges are used for the measurement of heat transfer rate, deposited on machineable glass ceramic blades. The inherently fast response of these transducers makes them useful for the investigation of boundary layer transition on blade surfaces and some typical results are included.

NASA Low-Speed Centrifugal Compressor for Fundamental Research

NASA Technical Reports Server (NTRS)

Wood, J. R.; Adam, P. W.; Buggele, A. E.

1983-01-01

A centrifugal compressor facility being built by the NASA Lewis Research Center is described; its purpose is to obtain benchmark experimental data for internal flow code verification and modeling. The facility will be heavily instrumented with standard pressure and temperature probes and have provisions for flow visualization and laser Doppler velocimetry. The facility will accommodate rotational speeds to 2400 rpm and will be rated at pressures to 1.25 atm. The initial compressor stage for testing is geometrically and dynamically representative of modern high-performance stages with the exception of Mach number levels. Design exit tip speed for the initial stage is 500 ft/sec with a pressure ratio of 1.17. The rotor exit backsweep is 55 deg from radial.

An Incremental Weighted Least Squares Approach to Surface Lights Fields

NASA Astrophysics Data System (ADS)

Coombe, Greg; Lastra, Anselmo

An Image-Based Rendering (IBR) approach to appearance modelling enables the capture of a wide variety of real physical surfaces with complex reflectance behaviour. The challenges with this approach are handling the large amount of data, rendering the data efficiently, and previewing the model as it is being constructed. In this paper, we introduce the Incremental Weighted Least Squares approach to the representation and rendering of spatially and directionally varying illumination. Each surface patch consists of a set of Weighted Least Squares (WLS) node centers, which are low-degree polynomial representations of the anisotropic exitant radiance. During rendering, the representations are combined in a non-linear fashion to generate a full reconstruction of the exitant radiance. The rendering algorithm is fast, efficient, and implemented entirely on the GPU. The construction algorithm is incremental, which means that images are processed as they arrive instead of in the traditional batch fashion. This human-in-the-loop process enables the user to preview the model as it is being constructed and to adapt to over-sampling and under-sampling of the surface appearance.

The quality of service in passenger transport terminals

NASA Astrophysics Data System (ADS)

Oprea, C.; Roşca, E.; Popa, M.; Ilie, A.; Dinu, O.; Roşca, M.

2016-11-01

The quality of service in transport terminals is differently perceived by engineers, economists, transport operators and sociologists. The traveler's perception is nevertheless decisive. The quality of service is well connected with the inside design of terminals, with the facilities in terminals and with the provided service standards. In order to provide a high level of service, the activities taking place in the public transport terminal and the maximum travelers flow size must be carefully analyzed and dimensioned. The purpose of modelling is to find the best route for each traveler from origin (entrance) to destination (exit) through all the intermediate service points, taking into consideration the instant network conditions. In developing the model we consider the walking, the waiting and the serving time. Using a simulation program written in ARENA we determine the waiting time. For validation, the model is used to evaluate the performance level in Bucharest Basarab station. By comparing the total walking distance for the possible routes and the utility function that describes the utility of all activities from entrance to exit we can find the optimal route.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liese, Eric; Zitney, Stephen E.

A multi-stage centrifugal compressor model is presented with emphasis on analyzing use of an exit flow coefficient vs. an inlet flow coefficient performance parameter to predict off-design conditions in the critical region of a supercritical carbon dioxide (CO 2) power cycle. A description of the performance parameters is given along with their implementation in a design model (number of stages, basic sizing, etc.) and a dynamic model (for use in transient studies). A design case is shown for two compressors, a bypass compressor and a main compressor, as defined in a process simulation of a 10 megawatt (MW) supercritical COmore » 2 recompression Brayton cycle. Simulation results are presented for a simple open cycle and closed cycle process with changes to the inlet temperature of the main compressor which operates near the CO 2 critical point. Results showed some difference in results using the exit vs. inlet flow coefficient correction, however, it was not significant for the range of conditions examined. Here, this paper also serves as a reference for future works, including a full process simulation of the 10 MW recompression Brayton cycle.« less

Statistical analysis of AFE GN&C aeropass performance

NASA Technical Reports Server (NTRS)

Chang, Ho-Pen; French, Raymond A.

1990-01-01

Performance of the guidance, navigation, and control (GN&C) system used on the Aeroassist Flight Experiment (AFE) spacecraft has been studied with Monte Carlo techniques. The performance of the AFE GN&C is investigated with a 6-DOF numerical dynamic model which includes a Global Reference Atmospheric Model (GRAM) and a gravitational model with oblateness corrections. The study considers all the uncertainties due to the environment and the system itself. In the AFE's aeropass phase, perturbations on the system performance are caused by an error space which has over 20 dimensions of the correlated/uncorrelated error sources. The goal of this study is to determine, in a statistical sense, how much flight path angle error can be tolerated at entry interface (EI) and still have acceptable delta-V capability at exit to position the AFE spacecraft for recovery. Assuming there is fuel available to produce 380 ft/sec of delta-V at atmospheric exit, a 3-sigma standard deviation in flight path angle error of 0.04 degrees at EI would result in a 98-percent probability of mission success.

COSMIC REIONIZATION ON COMPUTERS. ULTRAVIOLET CONTINUUM SLOPES AND DUST OPACITIES IN HIGH REDSHIFT GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khakhaleva-Li, Zimu; Gnedin, Nickolay Y., E-mail: zimu@uchicago.edu, E-mail: gnedin@fnal.gov

We compare the properties of stellar populations of model galaxies from the Cosmic Reionization On Computers (CROC) project with the exiting ultraviolet (UV) and IR data. Since CROC simulations do not follow cosmic dust directly, we adopt two variants of the dust-follows-metals ansatz to populate model galaxies with dust. Using the dust radiative transfer code Hyperion, we compute synthetic stellar spectra, UV continuum slopes, and IR fluxes for simulated galaxies. We find that the simulation results generally match observational measurements, but, perhaps, not in full detail. The differences seem to indicate that our adopted dust-follows-metals ansatzes are not fully sufficient.more » While the discrepancies with the exiting data are marginal, the future James Webb Space Telescope (JWST) data will be of much higher precision, rendering highly significant any tentative difference between theory and observations. It is, therefore, likely, that in order to fully utilize the precision of JWST observations, fully dynamical modeling of dust formation, evolution, and destruction may be required.« less

Camera Network Topology Discovery Literature Review

DTIC Science & Technology

2011-11-01

essential for 21st century military, enviromental and surveillance applications [Devarajan, Cheng & Radke 2008]. Computer networks pose several research...starting and ending points of object trajectories into entry/exit regions [Makris & Ellis 2003]. 3LDA is a new standard for document analysis. The model

49 CFR 571.217 - Standard No. 217; Bus emergency exits and window retention and release.

Code of Federal Regulations, 2010 CFR

2010-10-01

... shown in Figure 3A for a side emergency exit door, and in figure 3D for a rear emergency exit door. (b... § 571.217 see the List of CFR Sections Affected which appears in the Finding Aids section of the printed...

46 CFR 122.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Escape hatches and emergency exits. 122.606 Section 122.606 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING... Markings Required § 122.606 Escape hatches and emergency exits. All escape hatches and other emergency...

46 CFR 122.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Escape hatches and emergency exits. 122.606 Section 122.606 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING... Markings Required § 122.606 Escape hatches and emergency exits. All escape hatches and other emergency...

46 CFR 122.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Escape hatches and emergency exits. 122.606 Section 122.606 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING... Markings Required § 122.606 Escape hatches and emergency exits. All escape hatches and other emergency...

77 FR 3187 - Airworthiness Directives; the Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... of the hatch opening of the overwing emergency exit. This proposed AD would require repetitive... cracking on the lower main sill inner chord of the hatch opening of the overwing emergency exit, which could result in reduced structural integrity of the hatch opening of the overwing emergency exit and...

46 CFR 122.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Escape hatches and emergency exits. 122.606 Section 122.606 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING... Markings Required § 122.606 Escape hatches and emergency exits. All escape hatches and other emergency...

46 CFR 122.606 - Escape hatches and emergency exits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Escape hatches and emergency exits. 122.606 Section 122.606 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING... Markings Required § 122.606 Escape hatches and emergency exits. All escape hatches and other emergency...

40 CFR 63.104 - Heat exchange system requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... heat exchange system or at locations where the cooling water enters and exits each heat exchanger or any combination of heat exchangers. (i) For samples taken at the entrance and exit of recirculating... manufacturing process units. (iii) For samples taken at the entrance and exit of each heat exchanger or any...

14 CFR 91.607 - Emergency exits for airplanes carrying passengers for hire.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Emergency exits for airplanes carrying... Emergency exits for airplanes carrying passengers for hire. (a) Notwithstanding any other provision of this chapter, no person may operate a large airplane (type certificated under the Civil Air Regulations...

14 CFR 91.607 - Emergency exits for airplanes carrying passengers for hire.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Emergency exits for airplanes carrying... Emergency exits for airplanes carrying passengers for hire. (a) Notwithstanding any other provision of this chapter, no person may operate a large airplane (type certificated under the Civil Air Regulations...

14 CFR 91.607 - Emergency exits for airplanes carrying passengers for hire.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Emergency exits for airplanes carrying... Emergency exits for airplanes carrying passengers for hire. (a) Notwithstanding any other provision of this chapter, no person may operate a large airplane (type certificated under the Civil Air Regulations...

14 CFR 91.607 - Emergency exits for airplanes carrying passengers for hire.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Emergency exits for airplanes carrying... Emergency exits for airplanes carrying passengers for hire. (a) Notwithstanding any other provision of this chapter, no person may operate a large airplane (type certificated under the Civil Air Regulations...

29 CFR 1910.35 - Compliance with alternate exit-route codes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 1910.35 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Exit Routes and Emergency Planning § 1910.35...-route provisions of NFPA 101, Life Safety Code, 2009 edition, or the exit-route provisions of the...

14 CFR 91.607 - Emergency exits for airplanes carrying passengers for hire.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Emergency exits for airplanes carrying... Emergency exits for airplanes carrying passengers for hire. (a) Notwithstanding any other provision of this chapter, no person may operate a large airplane (type certificated under the Civil Air Regulations...

33 CFR 161.18 - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... call. H HOTEL Date, time and point of entry system Entry time expressed as in (B) and into the entry... KILO Date, time and point of exit from system Exit time expressed as in (B) and exit position expressed....; for a dredge or floating plant: configuration of pipeline, mooring configuration, number of assist...

49 CFR 571.217 - Standard No. 217; Bus emergency exits and window retention and release.

Code of Federal Regulations, 2011 CFR

2011-10-01

... shown in Figure 3A for a side emergency exit door, and in figure 3D for a rear emergency exit door. (b... § 571.217 see the List of CFR Sections Affected which appears in the Finding Aids section of the printed...

14 CFR 135.129 - Exit seating.

Code of Federal Regulations, 2013 CFR

2013-01-01

... functions of paragraph (d) of this section, the suitability of each person it permits to occupy an exit seat... certificate holder shall make the passenger exit seating determinations required by this paragraph in a non... is likely that the person would be unable to perform one or more of the applicable functions listed...

14 CFR 135.129 - Exit seating.

Code of Federal Regulations, 2012 CFR

2012-01-01

... functions of paragraph (d) of this section, the suitability of each person it permits to occupy an exit seat... certificate holder shall make the passenger exit seating determinations required by this paragraph in a non... is likely that the person would be unable to perform one or more of the applicable functions listed...

14 CFR 135.129 - Exit seating.

Code of Federal Regulations, 2014 CFR

2014-01-01

... functions of paragraph (d) of this section, the suitability of each person it permits to occupy an exit seat... certificate holder shall make the passenger exit seating determinations required by this paragraph in a non... is likely that the person would be unable to perform one or more of the applicable functions listed...

14 CFR 135.129 - Exit seating.

Code of Federal Regulations, 2011 CFR

2011-01-01

... functions of paragraph (d) of this section, the suitability of each person it permits to occupy an exit seat... certificate holder shall make the passenger exit seating determinations required by this paragraph in a non... is likely that the person would be unable to perform one or more of the applicable functions listed...

14 CFR 135.129 - Exit seating.

Code of Federal Regulations, 2010 CFR

2010-01-01

... functions of paragraph (d) of this section, the suitability of each person it permits to occupy an exit seat... certificate holder shall make the passenger exit seating determinations required by this paragraph in a non... is likely that the person would be unable to perform one or more of the applicable functions listed...

A parallel algorithm for finding the shortest exit paths in mines

NASA Astrophysics Data System (ADS)

Jastrzab, Tomasz; Buchcik, Agata

2017-11-01

In the paper we study the problem of finding the shortest exit path in an underground mine in case of emergency. Since emergency situations, such as underground fires, can put the miners' lives at risk, the ability to quickly determine the safest exit path is crucial. We propose a parallel algorithm capable of finding the shortest path between the safe exit point and any other point in the mine. The algorithm is also able to take into account the characteristics of individual miners, to make the path determination more reliable.

Development of an Energetic X-Ray Imaging Telescope Experiment (EXITE) and Associated Balloon Gondola System

NASA Technical Reports Server (NTRS)

1997-01-01

This is the Final Report for grant NAGW-624, which was our original grant to develop the Energetic X- ray Imaging Telescope Experiment (EXITE) and Associated Balloon Gondola. The EXITE grant was changed over to a new grant (from GSFC), NAG5-5103, beginning in FY97 and is currently very much continuing under that grant. The Final Report presented here then covers the EXITE development under the original grant, which in fact continued (with a 1 year no-cost extension) through December 31, 1997.

Two-dimensional Cascade Investigation of the Maximum Exit Tangential Velocity Component and Other Flow Conditions at the Exit of Several Turbine Blade Designs at Supercritical Pressure Ratios

NASA Technical Reports Server (NTRS)

Hauser, Cavour H; Plohr, Henry W

1951-01-01

The nature of the flow at the exit of a row of turbine blades for the range of conditions represented by four different blade configurations was evaluated by the conservation-of-momentum principle using static-pressure surveys and by analysis of Schlieren photographs of the flow. It was found that for blades of the type investigated, the maximum exit tangential-velocity component is a function of the blade geometry only and can be accurately predicted by the method of characteristics. A maximum value of exit velocity coefficient is obtained at a pressure ratio immediately below that required for maximum blade loading followed by a sharp drop after maximum blade loading occurs.

IR signature study of aircraft engine for variation in nozzle exit area

NASA Astrophysics Data System (ADS)

Baranwal, Nidhi; Mahulikar, Shripad P.

2016-01-01

In general, jet engines operate with choked nozzle during take-off, climb and cruise, whereas unchoking occurs while landing and taxiing (when engine is not running at full power). Appropriate thrust in an aircraft in all stages of the flight, i.e., take-off, climb, cruise, descent and landing is achieved through variation in the nozzle exit area. This paper describes the effect on thrust and IR radiance of a turbojet engine due to variation in the exit area of a just choked converging nozzle (Me = 1). The variations in the nozzle exit area result in either choking or unchoking of a just choked converging nozzle. Results for the change in nozzle exit area are analyzed in terms of thrust, mass flow rate and specific fuel consumption. The solid angle subtended (Ω) by the exhaust system is estimated analytically, for the variation in nozzle exit area (Ane), as it affects the visibility of the hot engine parts from the rear aspect. For constant design point thrust, IR radiance is studied from the boresight (ϕ = 0°, directly from the rear side) for various percentage changes in nozzle exit area (%ΔAne), in the 1.9-2.9 μm and 3-5 μm bands.

A balance of FGF and BMP signals regulates cell cycle exit and Equarin expression in lens cells

PubMed Central

Jarrin, Miguel; Pandit, Tanushree; Gunhaga, Lena

2012-01-01

In embryonic and adult lenses, a balance of cell proliferation, cell cycle exit, and differentiation is necessary to maintain physical function. The molecular mechanisms regulating the transition of proliferating lens epithelial cells to differentiated primary lens fiber cells are poorly characterized. To investigate this question, we used gain- and loss-of-function analyses to modulate fibroblast growth factor (FGF) and/or bone morphogenetic protein (BMP) signals in chick lens/retina explants. Here we show that FGF activity plays a key role for proliferation independent of BMP signals. Moreover, a balance of FGF and BMP signals regulates cell cycle exit and the expression of Ccdc80 (also called Equarin), which is expressed at sites where differentiation of lens fiber cells occurs. BMP activity promotes cell cycle exit and induces Equarin expression in an FGF-dependent manner. In contrast, FGF activity is required but not sufficient to induce cell cycle exit or Equarin expression. Furthermore, our results show that in the absence of BMP activity, lens cells have increased cell cycle length or are arrested in the cell cycle, which leads to decreased cell cycle exit. Taken together, these findings suggest that proliferation, cell cycle exit, and early differentiation of primary lens fiber cells are regulated by counterbalancing BMP and FGF signals. PMID:22718906

Medicare+Choice: what lies ahead?

PubMed

Layne, R Jeffrey

2002-03-01

Health plans have continued to exit the Medicare+Choice program in recent years, despite efforts of Congress and the Centers for Medicare and Medicaid Services (CMS) to reform the program. Congress and CMS therefore stand poised to make additional, substantial reforms to the program. CMS has proposed to consolidate its oversight of the program, extend the due date for Medicare+Choice plans to file their adjusted community rate proposals, revise risk-adjustment processes, streamline the marketing review process, enhance quality-improvement requirements, institute results based performance assessment audits, coordinate policy changes to coincide with contracting cycles, expand its fall advertising campaign for the program, provide better employer-based Medicare options for beneficiaries, and take steps to minimize beneficiary costs. Congressional leaders have proposed various legislative remedies to improve the program, including creation of an entirely new pricing structure for the program based on a competitive bidding process.

Of magic wands and kaleidoscopes: fixing problems in the individual market.

PubMed

Hall, Mark A

2002-01-01

Policy analysts sometimes imagine that problems in the individual market can be fixed by waving a magic wand that makes the individual market function more like the group market. However, prior studies reveal that purchasing cooperatives fail to achieve substantial economies of scale; market reforms that reduce the impact of medical underwriting are difficult to implement in the individual market; and it may not be as easy as imagined to induce people to purchase over the Internet or from new or smaller companies that are at higher risk for exiting the market. The best solution is to limit the use of subsidies to certain purchasing options, such as with purchasing cooperatives that abide by rating, issuance, and renewability rules. What is not acceptable is to hand people subsidies and send them to the unstructured and relatively unregulated individual market, nor will it work to give people unhindered choice between two basically different market segments.

Electrostatic dispersion lenses and ion beam dispersion methods

DOEpatents

Dahl, David A [Idaho Falls, ID; Appelhans, Anthony D [Idaho Falls, ID

2010-12-28

An EDL includes a case surface and at least one electrode surface. The EDL is configured to receive through the EDL a plurality of ion beams, to generate an electrostatic field between the one electrode surface and either the case surface or another electrode surface, and to increase the separation between the beams using the field. Other than an optional mid-plane intended to contain trajectories of the beams, the electrode surface or surfaces do not exhibit a plane of symmetry through which any beam received through the EDL must pass. In addition or in the alternative, the one electrode surface and either the case surface or the other electrode surface have geometries configured to shape the field to exhibit a less abrupt entrance and/or exit field transition in comparison to another electrostatic field shaped by two nested, one-quarter section, right cylindrical electrode surfaces with a constant gap width.

Lunar Habitat Airlock/Suitlock

NASA Technical Reports Server (NTRS)

Griffin, Brand Norman

2008-01-01

Airlocks for lunar Extravehicular Activity (EVA) will be significantly different than previous designs. Until now, airlocks operated infrequently and only in the "clean" weightless environment, but lunar airlocks are planned to be used much more often (every other day) in a dusty, gravity environment. Concepts for airlocks were analyzed by the NASA, JSC Habitability Focus Element during recent lunar outpost studies. Three airlock types were identified; an Airlock (AL) or independent pressure vessel with one hatch to the outside and the other to the Habitat. A Suitlock (SL) which shares a pressure bulkhead with the Habitat allowing rear-entry suits to remain on the dusty side while the crew enters/exits the Habitat. The third option is the Suitport (SP) which offers direct access from the habitable volume into an externally mounted suit. The SP concept was not compared, however between the AL and SL, the AL was favored.

Continuous-wave laser generated jets for needle free applications

PubMed Central

Visser, Claas Willem; Schlautmann, Stefan

2016-01-01

We designed and built a microfluidic device for the generation of liquid jets produced by thermocavitation. A continuous wave (CW) laser was focused inside a micro-chamber filled with a light-absorbing solution to create a rapidly expanding vapor bubble. The chamber is connected to a micro-channel which focuses and ejects the liquid jet through the exit. The bubble growth and the jet velocity were measured as a function of the devices geometry (channel diameter D and chamber width A). The fastest jets were those for relatively large chamber size with respect to the channel diameter. Elongated and focused jets up to 29 m/s for a channel diameter of 250 μm and chamber size of 700 μm were obtained. The proposed CW laser-based device is potentially a compact option for a practical and commercially feasible needle-free injector. PMID:26858816

Perspectives On Dilution Jet Mixing

NASA Technical Reports Server (NTRS)

Holdeman, J. D.; Srinivasan, R.

1990-01-01

NASA recently completed program of measurements and modeling of mixing of transverse jets with ducted crossflow, motivated by need to design or tailor temperature pattern at combustor exit in gas turbine engines. Objectives of program to identify dominant physical mechanisms governing mixing, extend empirical models to provide near-term predictive capability, and compare numerical code calculations with data to guide future analysis improvement efforts.

Modeling Navigation System Performance of a Satellite-Observing Star Tracker Tightly Integrated with an Inertial Measurement Unit

DTIC Science & Technology

2015-03-26

tracker, an Inertial Measurement Unit (IMU), and a barometric altimeter using an Extended Kalman Filter (EKF). Models of each of these components are...Positioning 15 2.5 Detector Device Improvement . . . . . . . . . . . . . . . 15 2.6 Kalman Filter . . . . . . . . . . . . . . . . . . . . . . . . 17 2.6.1...Extended Kalman Filter . . . . . . . . . . . . . 17 2.7 System Properties . . . . . . . . . . . . . . . . . . . . . 21 2.8 Sun Exitance

Birthdating Studies Reshape Models for Pituitary Gland Cell Specification

PubMed Central

Davis, Shannon W.; Mortensen, Amanda H.; Camper, Sally A.

2011-01-01

The intermediate and anterior lobes of the pituitary gland are derived from an invagination of oral ectoderm that forms Rathke’s pouch. During gestation proliferating cells are enriched around the pouch lumen, and they appear to delaminate as they exit the cell cycle and differentiate. During late mouse gestation and the post-natal period, anterior lobe progenitors re-enter the cell cycle and expand the populations of specialized, hormone-producing cells. At birth, all cell types are present, and their localization appears stratified based on cell type. We conducted a birth dating study of Rathke’s pouch derivatives to determine whether the location of specialized cells at birth is correlated with the timing of cell cycle exit. We find that all of the anterior lobe cell types initiate differentiation concurrently with a peak between e11.5 and e13.5. Differentiation of intermediate lobe melanotropes is delayed relative to anterior lobe cell types. We discovered that specialized cell types are not grouped together based on birth date and are dispersed throughout the anterior lobe. Thus, the apparent stratification of specialized cells at birth is not correlated with cell cycle exit. Thus, the currently popular model of cell specification, dependent upon timing of extrinsic, directional gradients of signaling molecules, needs revision. We propose that signals intrinsic to Rathke’s pouch are necessary for cell specification between e11.5 and e13.5 and that cell-cell communication likely plays an important role in regulating this process. PMID:21262217

Birthdating studies reshape models for pituitary gland cell specification.

PubMed

Davis, Shannon W; Mortensen, Amanda H; Camper, Sally A

2011-04-15

The intermediate and anterior lobes of the pituitary gland are derived from an invagination of oral ectoderm that forms Rathke's pouch. During gestation proliferating cells are enriched around the pouch lumen, and they appear to delaminate as they exit the cell cycle and differentiate. During late mouse gestation and the postnatal period, anterior lobe progenitors re-enter the cell cycle and expand the populations of specialized, hormone-producing cells. At birth, all cell types are present, and their localization appears stratified based on cell type. We conducted a birth dating study of Rathke's pouch derivatives to determine whether the location of specialized cells at birth is correlated with the timing of cell cycle exit. We find that all of the anterior lobe cell types initiate differentiation concurrently with a peak between e11.5 and e13.5. Differentiation of intermediate lobe melanotropes is delayed relative to anterior lobe cell types. We discovered that specialized cell types are not grouped together based on birth date and are dispersed throughout the anterior lobe. Thus, the apparent stratification of specialized cells at birth is not correlated with cell cycle exit. Thus, the currently popular model of cell specification, dependent upon timing of extrinsic, directional gradients of signaling molecules, needs revision. We propose that signals intrinsic to Rathke's pouch are necessary for cell specification between e11.5 and e13.5 and that cell-cell communication likely plays an important role in regulating this process. Copyright © 2011 Elsevier Inc. All rights reserved.

Plasma Potential and Langmuir Probe Measurements in the Near-field Plume of the NASA-457Mv2 Hall Thruster

NASA Technical Reports Server (NTRS)

Shastry, Rohit; Huang, Wensheng; Herman, Daniel A.; Soulas, George C.; Kamhawi, Hani

2012-01-01

In order to further the design of future high-power Hall thrusters and provide experimental validation for ongoing modeling efforts, plasma potential and Langmuir probe measurements were performed on the 50-kW NASA-457Mv2. An electrostatic probe array comprised of a near-field Faraday probe, single Langmuir probe, and emissive probe was used to interrogate the near-field plume from approximately 0.1 - 2.0 mean thruster diameters downstream of the thruster exit plane at the following operating conditions: 300 V, 400 V and 500 V at 30 kW and 500 V at 50 kW. Results have shown that the acceleration zone is limited to within 0.4 mean thruster diameters of the exit plane while the high-temperature region is limited to 0.25 mean thruster diameters from the exit plane at all four operating conditions. Maximum plasma potentials in the near-field at 300 and 400 V were approximately 50 V with respect to cathode potential, while maximum electron temperatures varied from 24 - 32 eV, depending on operating condition. Isothermal lines at all operating conditions were found to strongly resemble the magnetic field topology in the high-temperature regions. This distribution was found to create regions of high temperature and low density near the magnetic poles, indicating strong, thick sheath formation along these surfaces. The data taken from this study are considered valuable for future design as well as modeling validation.

PRELIMINARY DESIGN ANALYSIS OF AXIAL FLOW TURBINES

NASA Technical Reports Server (NTRS)

Glassman, A. J.

1994-01-01

A computer program has been developed for the preliminary design analysis of axial-flow turbines. Rapid approximate generalized procedures requiring minimum input are used to provide turbine overall geometry and performance adequate for screening studies. The computations are based on mean-diameter flow properties and a stage-average velocity diagram. Gas properties are assumed constant throughout the turbine. For any given turbine, all stages, except the first, are specified to have the same shape velocity diagram. The first stage differs only in the value of inlet flow angle. The velocity diagram shape depends upon the stage work factor value and the specified type of velocity diagram. Velocity diagrams can be specified as symmetrical, zero exit swirl, or impulse; or by inputting stage swirl split. Exit turning vanes can be included in the design. The 1991 update includes a generalized velocity diagram, a more flexible meanline path, a reheat model, a radial component of velocity, and a computation of free-vortex hub and tip velocity diagrams. Also, a loss-coefficient calibration was performed to provide recommended values for airbreathing engine turbines. Input design requirements include power or pressure ratio, mass flow rate, inlet temperature and pressure, and rotative speed. The design variables include inlet and exit diameters, stator angle or exit radius ratio, and number of stages. Gas properties are input as gas constant, specific heat ratio, and viscosity. The program output includes inlet and exit annulus dimensions, exit temperature and pressure, total and static efficiencies, flow angles, blading angles, and last stage absolute and relative Mach numbers. This program is written in FORTRAN 77 and can be ported to any computer with a standard FORTRAN compiler which supports NAMELIST. It was originally developed on an IBM 7000 series computer running VM and has been implemented on IBM PC computers and compatibles running MS-DOS under Lahey FORTRAN, and DEC VAX series computers running VMS. Format statements in the code may need to be rewritten depending on your FORTRAN compiler. The source code and sample data are available on a 5.25 inch 360K MS-DOS format diskette. This program was developed in 1972 and was last updated in 1991. IBM and IBM PC are registered trademarks of International Business Machines. MS-DOS is a registered trademark of Microsoft Corporation. DEC VAX, and VMS are trademarks of Digital Equipment Corporation.

SU-F-T-258: Efficacy of Exit Fluence-Based Dose Calculation for Prostate Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siebers, J; Gardner, J; Neal, B

Purpose: To investigate the efficacy of exit-fluence-based dose computation for prostate radiotherapy by determining if it estimates true dose more accurately than the original planning dose. Methods: Virtual exit-fluencebased dose computation was performed for 19 patients, each with 9–12 repeat CT images. For each patient, a 78 Gy treatment plan was created utilizing 5 mm CTV-to-PTV and OAR-to-PRV margins. A Monte Carlo framework was used to compute dose and exit-fluence images for the planning image and for each repeat CT image based on boney-anatomyaligned and prostate-centroid-aligned CTs. Identical source particles were used for the MC dose-computations on the planning andmore » repeat CTs to maximize correlation. The exit-fluence-based dose and image were computed by multiplying source particle weights by FC(x,y)=FP(x,y)/FT(x,y), where (x,y) are the source particle coordinates projected to the exit-fluence plane and we denote the dose/fluence from the plan by (DP,FP), from the repeat-CT as (DT,FT), and the exit-fluence computation by (DFC,FFC). DFC mimics exit-fluence backprojection through the planning image as FT=FFC. Dose estimates were intercompared to judge the efficacy of exit-fluence-based dose computation. Results: Boney- and prostate-centroid aligned results are combined as there is no statistical difference between them, yielding 420 dose comparisons per dose-volume metric. DFC is more accurate than DP for 46%, 33%, and 44% of cases in estimating CTV D98, D50, and D2 respectively. DFC improved rectum D50 and D2 estimates 54% and 49% respectively and bladder D50 and D2 47 and 49% respectively. While averaged over all patients and images DFC and DP were within 3.1% of DT, they differed from DT by as much as 22% for GTV D98, 71% for the Bladder D50, 17% for Bladder D2, 19% for Rectum D2. Conclusion: Exit-fluence based dose computations infrequently improve CTV or OAR dose estimates and should be used with caution. Research supported in part by Varian Medical Systems.« less

Long-term Effects of Psychosocial Work Stress in Midlife on Health Functioning After Labor Market Exit—Results From the GAZEL Study

PubMed Central

Sembajwe, Grace; Zins, Marie; Berkman, Lisa; Goldberg, Marcel; Siegrist, Johannes

2012-01-01

Objectives. To study long-term effects of psychosocial work stress in mid-life on health functioning after labor market exit using two established work stress models. Methods. In the frame of the prospective French Gazel cohort study, data on psychosocial work stress were assessed using the full questionnaires measuring the demand-control-support model (in 1997 and 1999) and the effort–reward imbalance model (in 1998). In 2007, health functioning was assessed, using the Short Form 36 mental and physical component scores. Multivariate regressions were calculated to predict health functioning in 2007, controlling for age, gender, social position, and baseline self-perceived health. Results. Consistent effects of both work stress models and their single components on mental and physical health functioning during retirement were observed. Effects remained significant after adjustment including baseline self-perceived health. Whereas the predictive power of both work stress models was similar in the case of the physical composite score, in the case of the mental health score, values of model fit were slightly higher for the effort–reward imbalance model (R²: 0.13) compared with the demand-control model (R²: 0.11). Conclusions. Findings underline the importance of working conditions in midlife not only for health in midlife but also for health functioning after labor market exit. PMID:22546992

The impact of ill health on exit from paid employment in Europe among older workers.

PubMed

van den Berg, Tilja; Schuring, Merel; Avendano, Mauricio; Mackenbach, Johan; Burdorf, Alex

2010-12-01

To determine the impact of ill health on exit from paid employment in Europe among older workers. Participants of the Survey on Health and Ageing in Europe (SHARE) in 11 European countries in 2004 and 2006 were selected when 50-63 years old and in paid employment at baseline (n=4611). Data were collected on self-rated health, chronic diseases, mobility limitations, obesity, smoking, alcohol use, physical activity and work characteristics. Participants were classified into employed, retired, unemployed and disabled at the end of the 2-year follow-up. Multinomial logistic regression was used to estimate the effect of different measures of ill health on exit from paid employment. During the 2-year follow-up, 17% of employed workers left paid employment, mainly because of early retirement. Controlling for individual and work related characteristics, poor self-perceived health was strongly associated with exit from paid employment due to retirement, unemployment or disability (ORs from 1.32 to 4.24). Adjustment for working conditions and lifestyle reduced the significant associations between ill health and exit from paid employment by 0-18.7%. Low education, obesity, low job control and effort-reward imbalance were associated with measures of ill health, but also risk factors for exit from paid employment after adjustment for ill health. Poor self-perceived health was strongly associated with exit from paid employment among European workers aged 50-63 years. This study suggests that the influence of ill health on exit from paid employment could be lessened by measures targeting obesity, problematic alcohol use, job control and effort-reward balance.

Interest Rates and Coupon Bonds in Quantum Finance

NASA Astrophysics Data System (ADS)

Baaquie, Belal E.

2009-09-01

1. Synopsis; 2. Interest rates and coupon bonds; 3. Options and option theory; 4. Interest rate and coupon bond options; 5. Quantum field theory of bond forward interest rates; 6. Libor Market Model of interest rates; 7. Empirical analysis of forward interest rates; 8. Libor Market Model of interest rate options; 9. Numeraires for bond forward interest rates; 10. Empirical analysis of interest rate caps; 11. Coupon bond European and Asian options; 12. Empirical analysis of interest rate swaptions; 13. Correlation of coupon bond options; 14. Hedging interest rate options; 15. Interest rate Hamiltonian and option theory; 16. American options for coupon bonds and interest rates; 17. Hamiltonian derivation of coupon bond options; Appendixes; Glossaries; List of symbols; Reference; Index.

Scramjet test flow reconstruction for a large-scale expansion tube, Part 2: axisymmetric CFD analysis

NASA Astrophysics Data System (ADS)

Gildfind, D. E.; Jacobs, P. A.; Morgan, R. G.; Chan, W. Y. K.; Gollan, R. J.

2018-07-01

This paper presents the second part of a study aiming to accurately characterise a Mach 10 scramjet test flow generated using a large free-piston-driven expansion tube. Part 1 described the experimental set-up, the quasi-one-dimensional simulation of the full facility, and the hybrid analysis technique used to compute the nozzle exit test flow properties. The second stage of the hybrid analysis applies the computed 1-D shock tube flow history as an inflow to a high-fidelity two-dimensional-axisymmetric analysis of the acceleration tube. The acceleration tube exit flow history is then applied as an inflow to a further refined axisymmetric nozzle model, providing the final nozzle exit test flow properties and thereby completing the analysis. This paper presents the results of the axisymmetric analyses. These simulations are shown to closely reproduce experimentally measured shock speeds and acceleration tube static pressure histories, as well as nozzle centreline static and impact pressure histories. The hybrid scheme less successfully predicts the diameter of the core test flow; however, this property is readily measured through experimental pitot surveys. In combination, the full test flow history can be accurately determined.

Distribution and spatial variation of hydrothermal faunal assemblages at Lucky Strike (Mid-Atlantic Ridge) revealed by high-resolution video image analysis

NASA Astrophysics Data System (ADS)

Cuvelier, Daphne; Sarrazin, Jozée; Colaço, Ana; Copley, Jon; Desbruyères, Daniel; Glover, Adrian G.; Tyler, Paul; Serrão Santos, Ricardo

2009-11-01

Whilst the fauna inhabiting hydrothermal vent structures in the Atlantic Ocean is reasonably well known, less is understood about the spatial distributions of the fauna in relation to abiotic and biotic factors. In this study, a major active hydrothermal edifice (Eiffel Tower, at 1690 m depth) on the Lucky Strike vent field (Mid-Atlantic Ridge (MAR)) was investigated. Video transects were carried out by ROV Victor 6000 and complete image coverage was acquired. Four distinct assemblages, ranging from dense larger-sized Bathymodiolus mussel beds to smaller-sized mussel clumps and alvinocaridid shrimps, and two types of substrata were defined based on high definition photographs and video imagery. To evaluate spatial variation, faunal distribution was mapped in three dimensions. A high degree of patchiness characterizes this 11 m high sulfide structure. The differences observed in assemblage and substratum distribution were related to habitat characteristics (fluid exits, depth and structure orientation). Gradients in community structure were observed, which coincided with an increasing distance from the fluid exits. A biological zonation model for the Eiffel Tower edifice was created in which faunal composition and distribution can be visually explained by the presence/absence of fluid exits.

AZO/Ag/AZO anode for resonant cavity red, blue, and yellow organic light emitting diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gentle, A. R., E-mail: angus.gentle@uts.edu.au; Smith, G. B.; Yambem, S. D.

Indium tin oxide (ITO) is the transparent electrode of choice for organic light-emitting diodes (OLEDs). Replacing ITO for cost and performance reasons is a major drive across optoelectronics. In this work, we show that changing the transparent electrode on red, blue, and yellow OLEDs from ITO to a multilayer buffered aluminium zinc oxide/silver/aluminium zinc oxide (AZO/Ag/AZO) substantially enhances total output intensity, with better control of colour, its constancy, and intensity over the full exit hemisphere. The thin Ag containing layer induces a resonant cavity optical response of the complete device. This is tuned to the emission spectra of the emissivemore » material while minimizing internally trapped light. A complete set of spectral intensity data is presented across the full exit hemisphere for each electrode type and each OLED colour. Emission zone modelling of output spectra at a wide range of exit angles to the normal was in excellent agreement with the experimental data and hence could, in principle, be used to check and adjust production settings. These multilayer transparent electrodes show significant potential for both eliminating indium from OLEDs and spectrally shaping the emission.« less

Scramjet test flow reconstruction for a large-scale expansion tube, Part 2: axisymmetric CFD analysis

NASA Astrophysics Data System (ADS)

Gildfind, D. E.; Jacobs, P. A.; Morgan, R. G.; Chan, W. Y. K.; Gollan, R. J.

2017-11-01

This paper presents the second part of a study aiming to accurately characterise a Mach 10 scramjet test flow generated using a large free-piston-driven expansion tube. Part 1 described the experimental set-up, the quasi-one-dimensional simulation of the full facility, and the hybrid analysis technique used to compute the nozzle exit test flow properties. The second stage of the hybrid analysis applies the computed 1-D shock tube flow history as an inflow to a high-fidelity two-dimensional-axisymmetric analysis of the acceleration tube. The acceleration tube exit flow history is then applied as an inflow to a further refined axisymmetric nozzle model, providing the final nozzle exit test flow properties and thereby completing the analysis. This paper presents the results of the axisymmetric analyses. These simulations are shown to closely reproduce experimentally measured shock speeds and acceleration tube static pressure histories, as well as nozzle centreline static and impact pressure histories. The hybrid scheme less successfully predicts the diameter of the core test flow; however, this property is readily measured through experimental pitot surveys. In combination, the full test flow history can be accurately determined.

Indicators of Club Management Practices and Biological Measurements of Patrons’ Drug and Alcohol Use

PubMed Central

Byrnes, Hilary F.; Miller, Brenda A.; Johnson, Mark B.; Voas, Robert B.

2015-01-01

Background Electronic Music Dance Events in nightclubs attract patrons with heavy alcohol/drug use. Public health concerns are raised from risks related to these behaviors. Practices associated with increased risk in these club settings need to be identified. Objectives The relationship between club management practices and biological measures of patrons’ alcohol/drug use is examined. Methods Observational data from 25 events across 6 urban clubs were integrated with survey data (N=738 patrons, 42.8% female) from patrons exiting these events, 2010–2012. Five indicators of club management practices were examined using mixed model regressions: club security, bar crowding, safety signs, serving intoxicated patrons, and isolation. Results Analyses revealed that serving intoxicated patrons and safety signs were related to less substance use. Specifically, serving intoxicated patrons was related to heavy alcohol and drug use at exit, while safety signs were marginally related to less exit drug use. Conclusions/Importance Findings indicate observable measures in nightclubs provide important indicators for alcohol/drug use, suggesting practices to target. Study strengths include the use of biological measures of substance use on a relatively large scale. Limitations and future directions are discussed. PMID:24832721

A simple analytical method to estimate all exit parameters of a cross-flow air dehumidifier using liquid desiccant.

PubMed

Bassuoni, M M

2014-03-01

The dehumidifier is a key component in liquid desiccant air-conditioning systems. Analytical solutions have more advantages than numerical solutions in studying the dehumidifier performance parameters. This paper presents the performance results of exit parameters from an analytical model of an adiabatic cross-flow liquid desiccant air dehumidifier. Calcium chloride is used as desiccant material in this investigation. A program performing the analytical solution is developed using the engineering equation solver software. Good accuracy has been found between analytical solution and reliable experimental results with a maximum deviation of +6.63% and -5.65% in the moisture removal rate. The method developed here can be used in the quick prediction of the dehumidifier performance. The exit parameters from the dehumidifier are evaluated under the effects of variables such as air temperature and humidity, desiccant temperature and concentration, and air to desiccant flow rates. The results show that hot humid air and desiccant concentration have the greatest impact on the performance of the dehumidifier. The moisture removal rate is decreased with increasing both air inlet temperature and desiccant temperature while increases with increasing air to solution mass ratio, inlet desiccant concentration, and inlet air humidity ratio.

Low-Level Jets and Their Effects on the South American Summer Climate as Simulated by the NCEP Eta Model(.

NASA Astrophysics Data System (ADS)

Vernekar, Anandu D.; Kirtman, Ben P.; Fennessy, Michael J.

2003-01-01

The National Centers for Environmental Prediction (NCEP) Eta Model (80 km, 38L) is used to simulate the tropical South American summer (January-March) climate for 1983, 1985, 1987, 1989, and 1991 using lateral boundary conditions from the NCEP-National Center for Atmospheric Research (NCAR) reanalysis. Simulations of the lower tropospheric circulation and precipitation are analyzed to study the variability on diurnal, intraseasonal, and interannual timescales. The results are compared with observations and previous studies.The Eta Model produces better regional circulation details, such as low-level jets (LLJs), than does the reanalysis because of its higher resolution, more realistic topography and coastal geometry, and because of its ability to realistically simulate the effects of mesoscale circulation on the time-mean flow. The model detects not only the LLJ east of the Andes Mountains and the LLJ west of northern Cordillera Occidental, which have been reported in previous studies, but it also detects three distinct LLJs just north of the equator embedded in the strong northeasterly trade winds over Colombia, Venezuela, and Guiana. All the LLJs show strong diurnal variability with a nocturnal maximum. The LLJ east of the Andes Mountains brings warm moist air from the Amazon basin to the Gran Chaco region where the jet exits. The moisture convergence in the jet exit region creates favorable conditions for precipitation. Hence, the precipitation over the region also shows strong diurnal variability with a nocturnal maximum. The LLJs just north of the equator bring moisture from the tropical Atlantic Ocean, the western Caribbean Sea, and the Gulf of Panama to their exit regions over the northern Amazon basin and west coasts of Colombia and Ecuador. The precipitation over these regions also has diurnal variability with a nocturnal maximum. The diurnal variability of precipitation over most of the Tropics has an afternoon rainfall maximum except for regions influenced by LLJs, which have a nocturnal rainfall maximum. The intraseasonal variability of the LLJs is episodic with an approximate period of 20 days. The interannual variability of the LLJs is dominated by the ENSO cycle. The LLJ east of the Andes Mountains is stronger in the warm phase of ENSO than in the cold phase. However, the model has some difficulty simulating the observed relationship between the strength of LLJ and precipitation, but the model succeeds in the case of LLJs just north of the equator. For example, these LLJs are weaker in the warm phase of ENSO than in the cold phase. Hence, during the warm (cold) phase of ENSO, dry (wet) conditions normally occur over the northern part of the Amazon basin, which is the exit region of these LLJs.

Rapid Ice Loss at Vatnajokull,Iceland Since Late 1990s Constrained by Synthetic Aperture Radar Interferometry

NASA Astrophysics Data System (ADS)

Zhao, W.; Amelung, F.; Dixon, T. H.; Wdowinski, S.

2012-12-01

Synthetic aperture radar interferometry time series is applied over Vatnajokull, Iceland by using 15 years ERS data. Ice loss at Vatnajokull accelerates since late 1990s especially after 21th century. Clear uplift signal due to ice mass loss is detected. The rebound signal is generally linear and increases a little bit after 2000. The relative annual velocity (GPS station 7485 as reference) is about 12 mm/yr at the ice cap edge, which matches the previous studies using GPS. The standard deviation compared to 11 GPS stations in this area is about 2 mm/yr. A relative-value modeling method ignoring the effect of viscous flow is chosen assuming elastic half space earth. The final ice loss estimation - 83 cm/yr - matches the climatology model with ground observations. Small Baseline Subsets is applied for time series analysis. Orbit error coupling with long wavelength phase trend due to horizontal plate motion is removed based on a second polynomial model. For simplicity, we do not consider atmospheric delay in this area because of no complex topography and small-scale turbulence is eliminated well after long-term average when calculating the annual mean velocity. Some unwrapping error still exits because of low coherence. Other uncertainties can be the basic assumption of ice loss pattern and spatial variation of the elastic parameters. It is the first time we apply InSAR time series for ice mass balance study and provide detailed error and uncertainty analysis. The successful of this application proves InSAR as an option for mass balance study and it is also important for validation of different ice loss estimation techniques.

34 CFR 361.88 - Reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... RSA-911 data: (1) The number of individuals who exited the VR program in each closure category as specified in the definition of “Exit the VR program” under § 361.81. (2) The number of individuals who exited the VR program in competitive, self-, or BEP employment with earnings at or above the minimum wage...

34 CFR 361.88 - Reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... RSA-911 data: (1) The number of individuals who exited the VR program in each closure category as specified in the definition of “Exit the VR program” under § 361.81. (2) The number of individuals who exited the VR program in competitive, self-, or BEP employment with earnings at or above the minimum wage...

Exit Examinations, Peer Academic Climate, and Adolescents' Developmental Outcomes

ERIC Educational Resources Information Center

Benner, Aprile D.

2013-01-01

Implications of high school exit examination performance were examined with a sample of 672 racial/ethnic minority students. Exit examination failure in the 10th grade was negatively linked to subsequent grade point average, school engagement, and school belonging one year later, controlling for outcomes prior to taking the examination.…

Jet Nozzle Having Centerbody for Enhanced Exit Area Mixing

NASA Technical Reports Server (NTRS)

Seiner, John M. (Inventor); Gilinsky, Mikhail M. (Inventor)

1999-01-01

A nozzle arrangement includes a nozzle and a centerbody. The longitudinal axis of the centerbody is coaxially aligned with the nozzle. The centerbody has a free end portion shaped to create vortices in exhaust exiting the exit area. The vortices enhance mixing action in the exhaust and reduce exhaust noise while augmenting thrust.

Curriculum Development Guide Based on a Technical Program.

ERIC Educational Resources Information Center

Belle-Isle, Louis Phillip

This "Guide" is intended for educators who have been mandated to develop or modify an educational program's curriculum. The guide presupposes the formulation of an exit-profile and focuses exclusively on activities after the exit-profile has been developed. The development of a curriculum is based on an exit-profile that mirrors the…

34 CFR 361.88 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... RSA-911 data: (1) The number of individuals who exited the VR program in each closure category as specified in the definition of “Exit the VR program” under § 361.81. (2) The number of individuals who exited the VR program in competitive, self-, or BEP employment with earnings at or above the minimum wage...

34 CFR 361.88 - Reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... RSA-911 data: (1) The number of individuals who exited the VR program in each closure category as specified in the definition of “Exit the VR program” under § 361.81. (2) The number of individuals who exited the VR program in competitive, self-, or BEP employment with earnings at or above the minimum wage...

34 CFR 361.88 - Reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... RSA-911 data: (1) The number of individuals who exited the VR program in each closure category as specified in the definition of “Exit the VR program” under § 361.81. (2) The number of individuals who exited the VR program in competitive, self-, or BEP employment with earnings at or above the minimum wage...

45 CFR 670.34 - Entry and exit ports.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 45 Public Welfare 3 2013-10-01 2013-10-01 false Entry and exit ports. 670.34 Section 670.34 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Import Into and Export From the United States § 670.34 Entry and exit ports. (a...

45 CFR 670.34 - Entry and exit ports.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 45 Public Welfare 3 2014-10-01 2014-10-01 false Entry and exit ports. 670.34 Section 670.34 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Import Into and Export From the United States § 670.34 Entry and exit ports. (a...

45 CFR 670.34 - Entry and exit ports.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 45 Public Welfare 3 2011-10-01 2011-10-01 false Entry and exit ports. 670.34 Section 670.34 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Import Into and Export From the United States § 670.34 Entry and exit ports. (a...

45 CFR 670.34 - Entry and exit ports.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 45 Public Welfare 3 2012-10-01 2012-10-01 false Entry and exit ports. 670.34 Section 670.34 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Import Into and Export From the United States § 670.34 Entry and exit ports. (a...