Love of Comrades: The Urbanization of Community in Walt Whitman\u27s Poetry and Pragmatist Philosophy

Argues that the social crisis produced by urbanization shaped Whitman\u27s poetry and pragmatist thought in similar ways, and examines Whitman\u27s struggles with skepticism and relativism in light of his straddling of rural and urban experience, finding that Whitman\u27s untamed flow of sympathy in his urban poems of 1855 and 1856 gives way to an increasing urbane doubt and withdrawal from the city in his 1860 Calamus poems

Equity Audits of Ethnicity in Three Transitional Series: Moving Toward Diverse Series Books for Today’s Young Readers

This manuscript explores representations of protagonists of various multicultural backgrounds in three transitional series. Prior studies, such as Gangi (2008) and Green and Hopenwasser (2017), exposed the deficiencies of multicultural literature in elementary classrooms, particularly among transitional series books. Green and Hopenwasser emphasize the developmental importance of equal representation in transitional books with characters of diverse ethnicities, because they act as mirrors and windows for students to learn, grow, and reflect. These studies argue that in order to allow children to see themselves and to develop a positive self-image in primary grades, it is critical for teachers to be thoughtful while choosing series books.  For the purposes of this study, to explore ethnic and racial representations of protagonists with the actual demographics of third graders, researchers conducted an equity audit on three transitional series, published across different decades and commonly found in elementary classrooms. Equity audit data show multicultural representations lacking. In order for children to see healthy role models who mirror their own racial and ethnic contexts, authors describe the importance of teachers choosing series with strong, diverse protagonists to include in their classroom libraries

A Simple HCCI Engine Model for Control

The homogeneous charge compression ignition (HCCI) engine is an attractive technology because of its high efficiency and low emissions. However, HCCI lacks a direct combustion trigger making control of combustion timing challenging, especially during transients. To aid in HCCI engine control we present a simple model of the HCCI combustion process valid over a range of intake pressures, intake temperatures, equivalence ratios, and engine speeds. The model provides an estimate of the combustion timing on a cycle-by-cycle basis. An ignition threshold, which is a function of the in-cylinder motored temperature and pressure is used to predict start of combustion. This model allows the synthesis of nonlinear control laws, which can be utilized for control of an HCCI engine during transients

Nozzle Plume Impingement on Spacecraft Surfaces: Effects of Surface Roughness

Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S) Air Force Research Laboratory (AFMC) AFRL/PRS SPONSOR/MONITOR'S Pollux Drive NUMBER(S) Edwards AFB CA 93524-70448 AFRL-PR-ED-JA-2005-306 DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release; distribution unlimited (PA no. AFRL-ERS-PAS-2005-219). SUPPLEMENTARY NOTES Published in Journal of Spacecraft and Rockets, AIAA-2005-5065. ABSTRACT An experimental and numerical effort was undertaken to assess the effects of a cold gas (T 0 -300 K) nozzle plume impinging on simulated spacecraft surfaces. The nozzle flow impingement is investigated experimentally using a nano-Newton resolution force balance and numerically using the Direct Simulation Monte Carlo (DSMC) numerical technique. The Reynolds number range investigated in this study is from approximately 2 to 350 using nitrogen propellant. The thrust produced by the nozzle was first assessed on a force balance to provide a baseline case. Subsequently, aluminum plates were attached to the same force balance parallel to the plume flow to simulate spacecraft surfaces in proximity to the thruster. Three plates were used in this study, an electropolished plate with smooth surface, and two rough surface plates with equally spaced rectangular and triangular grooves. A 15% degradation in thrust was observed both experimentally and numerically for the plate relative to the free plume expansion case. The effect of surface roughness on thrust was found to be small due to molecules backscattered from the plate to the nozzle plenum wall. Additionally, the influence of surface roughness in the diverging part of the nozzle on thrust was examined numerically and found to be significant at Reynolds numbers less than 10. Abstract An experimental and numerical effort was undertaken to assess the effects of a cold gas (T 0 =300 K) nozzle plume impinging on a simulated spacecraft surface. The nozzle flow impingement is investigated experimentally using a nano-Newton resolution force balance and numerically using the Direct Simulation Monte Carlo (DSMC) numerical technique. The Reynolds number range investigated in this study is from approximately 2 to 600 using nitrogen propellant. The thrust produced by the nozzle was first assessed on a force balance to provide a baseline case. Subsequently, aluminum plates were attached to the same force balance parallel to the plume flow. Three plates were used in this study, an electropolished plate with smooth surface, and two rough surface plates with equally spaced rectangular and triangular grooves. A 15% degradation in thrust was observed both experimentally and numerically for the plate relative to the free plume expansion case. The effect of surface roughness on thrust was found to be small due to molecules back scattered from the plate to the plenum wall. Additionally, the influence of surface rougness in the diverging part of the nozzle on nozzle thrust was examined numerically, and found to be significant at Reynolds numbers on the order or less than 10

Characteristics of Knock in Hydrogen-Oxygen-Argon SI Engine

A promising approach for improving the efficiency of internal combustion engines is to employ a working fluid with a high specific heat ratio such as the noble gas argon. Moreover, all harmful emissions are eliminated when the intake charge is composed of oxygen, nonreactive argon, and hydrogen fuel. Previous research demonstrated indicated thermal efficiencies greater than 45% at 5.5 compression ratio in engines operating with hydrogen, oxygen, and argon. However, knock limits spark advance and increasing the efficiency further. Conditions under which knock occurs in such engines differs from typical gasoline fueled engines. In-cylinder temperatures using hydrogen-oxygen-argon are higher due to the high specific heat ratio and pressures are lower because of the low compression ratio. Better understanding of knock under these conditions can lead to operating strategies that inhibit knock and allow operation closer to the knock limit. In this work we compare knock with a hydrogen, oxygen, and argon mixture to that of air-gasoline mixtures in a variable compression ratio cooperative fuels research (CFR) engine. The focus is on stability of knocking phenomena, as well as, amplitude and frequency of the resulting pressure waves

How do patient characteristics influence informal payments for inpatient and outpatient health care in Albania: Results of logit and OLS models using Albanian LSMS 2005

Abstract Background Informal payments for health care are common in most former communist countries. This paper explores the demand side of these payments in Albania. By using data from the Living Standard Measurement Survey 2005 we control for individual determinants of informal payments in inpatient and outpatient health care. We use these results to explain the main factors contributing to the occurrence and extent of informal payments in Albania. Methods Using multivariate methods (logit and OLS) we test three models to explain informal payments: the cultural, economic and governance model. The results of logit models are presented here as odds ratios (OR) and results from OLS models as regression coefficients (RC). Results Our findings suggest differences in determinants of informal payments in inpatient and outpatient care. Generally our results show that informal payments are dependent on certain characteristics of patients, including age, area of residence, education, health status and health insurance. However, they are less dependent on income, suggesting homogeneity of payments across income categories. Conclusions We have found more evidence for the validity of governance and economic models than for the cultural model.</p