ERIC Educational Resources Information Center
Bronstein, Laura R.; Ball, Annahita; Mellin, Elizabeth A.; Wade-Mdivanian, Rebecca; Anderson-Butcher, Dawn
2011-01-01
The purpose of this article is to share results of a mixed-methods research study designed to shed light on similarities and differences between school-employed and agency-employed school-based social workers' preparation and practice as a precursor for collaboration in expanded school mental health. Online survey data from a national sample of…
Actions speak louder than words: Outsiders' perceptions of diversity mixed messages.
Windscheid, Leon; Bowes-Sperry, Lynn; Kidder, Deborah L; Cheung, Ho Kwan; Morner, Michèle; Lievens, Filip
2016-09-01
To attract a gender diverse workforce, many employers use diversity statements to publicly signal that they value gender diversity. However, this often represents a misalignment between words and actions (i.e., a diversity mixed message) because most organizations are male dominated, especially in board positions. We conducted 3 studies to investigate the potentially indirect effect of such diversity mixed messages through perceived behavioral integrity on employer attractiveness. In Study 1, following a 2 × 2 design, participants (N = 225) were either shown a pro gender diversity statement or a neutral statement, in combination with a gender diverse board (4 men and 4 women) or a uniform all-male board (8 men). Participants' perceived behavioral integrity of the organization was assessed. In Study 2, participants (N = 251) either read positive or negative reviews of the organization's behavioral integrity. Employer attractiveness was then assessed. Study 3 (N = 427) investigated the impact of board gender composition on perceived behavioral integrity and employer attractiveness using a bootstrapping procedure. Both the causal-chain design of Study 1 and 2, as well as the significance test of the proposed indirect relationship in Study 3, revealed that a diversity mixed message negatively affected an organization's perceived behavioral integrity, and low behavioral integrity in turn negatively impacted employer attractiveness. In Study 3, there was also evidence for a tipping point (more than 1 woman on the board was needed) with regard to participants' perceptions of the organization's behavioral integrity. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Women's Employment Status, Coercive Control, and Intimate Partner Violence in Mexico
ERIC Educational Resources Information Center
Villarreal, Andres
2007-01-01
Findings from previous studies examining the relation between women's employment and the risk of intimate partner violence have been mixed. Some studies find greater violence toward women who are employed, whereas others find the opposite relation or no relation at all. I propose a new framework in which a woman's employment status and her risk of…
29 CFR 1614.302 - Mixed case complaints.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 4 2012-07-01 2012-07-01 false Mixed case complaints. 1614.302 Section 1614.302 Labor... EMPLOYMENT OPPORTUNITY Related Processes § 1614.302 Mixed case complaints. (a) Definitions—(1) Mixed case complaint. A mixed case complaint is a complaint of employment discrimination filed with a federal agency...
29 CFR 1614.302 - Mixed case complaints.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 4 2014-07-01 2014-07-01 false Mixed case complaints. 1614.302 Section 1614.302 Labor... EMPLOYMENT OPPORTUNITY Related Processes § 1614.302 Mixed case complaints. (a) Definitions—(1) Mixed case complaint. A mixed case complaint is a complaint of employment discrimination filed with a federal agency...
29 CFR 1614.302 - Mixed case complaints.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 4 2013-07-01 2013-07-01 false Mixed case complaints. 1614.302 Section 1614.302 Labor... EMPLOYMENT OPPORTUNITY Related Processes § 1614.302 Mixed case complaints. (a) Definitions—(1) Mixed case complaint. A mixed case complaint is a complaint of employment discrimination filed with a federal agency...
29 CFR 1614.302 - Mixed case complaints.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 4 2011-07-01 2011-07-01 false Mixed case complaints. 1614.302 Section 1614.302 Labor... EMPLOYMENT OPPORTUNITY Related Processes § 1614.302 Mixed case complaints. (a) Definitions—(1) Mixed case complaint. A mixed case complaint is a complaint of employment discrimination filed with a federal agency...
29 CFR 1614.302 - Mixed case complaints.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 4 2010-07-01 2010-07-01 false Mixed case complaints. 1614.302 Section 1614.302 Labor... EMPLOYMENT OPPORTUNITY Related Processes § 1614.302 Mixed case complaints. (a) Definitions—(1) Mixed case complaint. A mixed case complaint is a complaint of employment discrimination filed with a federal agency...
ERIC Educational Resources Information Center
Radford, Alexandria Walton; Robles, Jessica; Cataylo, Stacey; Horn, Laura; Thornton, Jessica; Whitfield, Keith E.
2014-01-01
While press coverage of MOOCs (massive open online courses) has been considerable and major MOOC providers are beginning to realize that employers may be a market for their courses, research on employers' receptivity to using MOOCs is scarce. To help fill this gap, the Finding and Developing Talent study surveyed 103 employers and interviewed a…
Theoretical and numerical studies of chaotic mixing
NASA Astrophysics Data System (ADS)
Kim, Ho Jun
Theoretical and numerical studies of chaotic mixing are performed to circumvent the difficulties of efficient mixing, which come from the lack of turbulence in microfluidic devices. In order to carry out efficient and accurate parametric studies and to identify a fully chaotic state, a spectral element algorithm for solution of the incompressible Navier-Stokes and species transport equations is developed. Using Taylor series expansions in time marching, the new algorithm employs an algebraic factorization scheme on multi-dimensional staggered spectral element grids, and extends classical conforming Galerkin formulations to nonconforming spectral elements. Lagrangian particle tracking methods are utilized to study particle dispersion in the mixing device using spectral element and fourth order Runge-Kutta discretizations in space and time, respectively. Comparative studies of five different techniques commonly employed to identify the chaotic strength and mixing efficiency in microfluidic systems are presented to demonstrate the competitive advantages and shortcomings of each method. These are the stirring index based on the box counting method, Poincare sections, finite time Lyapunov exponents, the probability density function of the stretching field, and mixing index inverse, based on the standard deviation of scalar species distribution. Series of numerical simulations are performed by varying the Peclet number (Pe) at fixed kinematic conditions. The mixing length (lm) is characterized as function of the Pe number, and lm ∝ ln(Pe) scaling is demonstrated for fully chaotic cases. Employing the aforementioned techniques, optimum kinematic conditions and the actuation frequency of the stirrer that result in the highest mixing/stirring efficiency are identified in a zeta potential patterned straight micro channel, where a continuous flow is generated by superposition of a steady pressure driven flow and time periodic electroosmotic flow induced by a stream-wise AC electric field. Finally, it is shown that the invariant manifold of hyperbolic periodic point determines the geometry of fast mixing zones in oscillatory flows in two-dimensional cavity.
An Exploratory Investigation into Family Perspectives after the Family Employment Awareness Training
ERIC Educational Resources Information Center
Francis, Grace L.; Gross, Judith M. S.; Turnbull, Ann P.; Turnbull, H. Rutherford, III
2015-01-01
Competitive employment (i.e., employment in community settings among people without disabilities for minimum wage or higher) improves quality of life for people with disabilities who have individualized support needs (ISN). However, attaining competitive employment can be challenging for people with ISN. This study used a mixed methods design to…
Veteran Teacher Engagement in Site-Based Professional Development: A Mixed Methods Study
ERIC Educational Resources Information Center
Houston, Biaze L.
2016-01-01
This research study examined how teachers self-report their levels of engagement, which factors they believe contribute most to their engagement, and which assumptions of andragogy most heavily influence teacher engagement in site-based professional development. This study employed a convergent parallel mixed methods design to study veteran…
A common soil handling technique can generate incorrect estimates of soil biota effects on plants
USDA-ARS?s Scientific Manuscript database
Several plant-soil biota (PSB) studies were recently published in high profile journals that used the suspect “mixed soil sampling” methodology. To explore the extent to which mixing field samples (i.e. employing mixed soil sample designs) can generate erroneous conclusions, we used real data to pa...
ERIC Educational Resources Information Center
Bristow, Susan
2013-01-01
Employers of newly hired higher education graduates report their new workforce is not prepared. Further research was required to discover insights to the workforce readiness gap. This concurrent mixed methods study explored what competencies influenced employer's perceptions of the work-readiness of Information Systems (ISYS) undergraduate…
ERIC Educational Resources Information Center
Kaehne, Axel; Beyer, Stephen
2013-01-01
The article reports the evaluation of a small-scale-supported employment project in a local authority in England. The study examined whether or not the peer support model could be used to deliver supported employment to a group of young people with intellectual disabilities. We utilised a mixed-method approach involving activity data, family…
ERIC Educational Resources Information Center
Lovett, Jennifer Nickell
2016-01-01
The purpose of this study is to provide researchers, mathematics educators, and statistics educators information about the current state of preservice secondary mathematics teachers' preparedness to teach statistics. To do so, this study employed an explanatory mixed methods design to quantitatively examine the statistical knowledge and statistics…
ERIC Educational Resources Information Center
Gennetian, Lisa A.; Crosby, Danielle A.; Huston, Aletha C.; Lowe, Edward D.
2004-01-01
Policymakers have long recognized child care as a key ingredient in low-income parents' employability. We examine the effects of expansions in child care policies that were bundled with a mix of employment-related policies and implemented as part of several random assignment studies on families' child care access and cost. Almost all of these…
Internet-Mediated Technologies and Mixed Methods Research: Problems and Prospects
ERIC Educational Resources Information Center
Hesse-Biber, Sharlene; Griffin, Amy J.
2013-01-01
This article provides an examination of a range of mixed methods research projects that employ Internet-mediated technologies (IMT) for data collection. Using a case study approach, this article allows for the uncovering of a process by which IMT are used as a data collection medium in mixed methods praxis. Under the theoretical position of medium…
Fuel-Air Mixing and Combustion in Scramjets
NASA Technical Reports Server (NTRS)
Drummond, J. P.; Diskin, Glenn S.; Cutler, A. D.
2002-01-01
Activities in the area of scramjet fuel-air mixing and combustion associated with the Research and Technology Organization Working Group on Technologies for Propelled Hypersonic Flight are described. Work discussed in this paper has centered on the design of two basic experiments for studying the mixing and combustion of fuel and air in a scramjet. Simulations were conducted to aid in the design of these experiments. The experimental models were then constructed, and data were collected in the laboratory. Comparison of the data from a coaxial jet mixing experiment and a supersonic combustor experiment with a combustor code were then made and described. This work was conducted by NATO to validate combustion codes currently employed in scramjet design and to aid in the development of improved turbulence and combustion models employed by the codes.
The Role of Numeracy Skills in Graduate Employability
ERIC Educational Resources Information Center
Durrani, Naureen; Tariq, Vicki N.
2012-01-01
Purpose: The purpose of this article is to explore the role and importance of numeracy skills in graduate recruitment within a diversity of employment sectors. Design/methodology/approach: The results of a mixed-methods study, involving three online surveys (including an employer survey), student focus group sessions and interviews with tutors,…
Reading Strategies among ESL Malaysian Secondary School Students
ERIC Educational Resources Information Center
Semtin, Semry Anak; Maniam, Mahendran
2015-01-01
This study aimed to investigate the types of cognitive and metacognitive reading strategies employed by secondary school students in Malaysia to improve their comprehension. The study employed a mixed-method approach which involves the instruments of a questionnaire and an interview. This study was conducted at SMK Kapit, involving ninety Form 4…
Learning and Study Strategies of Students with Traumatic Brain Injury: A Mixed Method Study
ERIC Educational Resources Information Center
Bush, Erin; Hux, Karen; Zickefoose, Samantha; Simanek, Gina; Holmberg, Michelle; Henderson, Ambyr
2011-01-01
The purpose of this research was to explore the perceptions of four college students with severe traumatic brain injury and people associated with them regarding the use of learning skills and study strategies. The researchers employed a concurrent mixed method design using descriptive quantitative data as well as qualitative multiple case study…
Correlational Analysis of Servant Leadership and School Climate
ERIC Educational Resources Information Center
Black, Glenda Lee
2010-01-01
The purpose of this mixed-method research study was to determine the extent that servant leadership was correlated with perceptions of school climate to identify whether there was a relationship between principals' and teachers' perceived practice of servant leadership and of school climate. The study employed a mixed-method approach by first…
Mixed Resilience: A Study of Multiethnic Mexican American Stress and Coping in Arizona
ERIC Educational Resources Information Center
Jackson, Kelly F.; Wolven, Thera; Aguilera, Kimberly
2013-01-01
Guided by an integrated framework of resilience, this in-depth qualitative study examined the major stressors persons of multiethnic Mexican American heritage encountered in their social environments related to their mixed identity and the resilience enhancing processes they employed to cope with these stressors. Life-story event narratives were…
Mixed time integration methods for transient thermal analysis of structures, appendix 5
NASA Technical Reports Server (NTRS)
Liu, W. K.
1982-01-01
Mixed time integration methods for transient thermal analysis of structures are studied. An efficient solution procedure for predicting the thermal behavior of aerospace vehicle structures was developed. A 2D finite element computer program incorporating these methodologies is being implemented. The performance of these mixed time finite element algorithms can then be evaluated employing the proposed example problem.
van der Biezen, Mieke; Derckx, Emmy; Wensing, Michel; Laurant, Miranda
2017-02-07
Due to the increasing demand on primary care, it is not only debated whether there are enough general practitioners (GPs) to comply with these demands but also whether specific tasks can be performed by other care providers. Although changing the workforce skill mix care by employing Physician Assistants (PAs) and Nurse Practitioners (NPs) has proven to be both effective and safe, the implementation of those professionals differs widely between and within countries. To support policy making regarding PAs/NPs in primary care, the aim of this study is to provide insight into factors influencing the decision of GPs and managers to train and employ a PA/NP within their organisation. A qualitative study was conducted in 2014 in which 7 managers of out-of-hours primary care services and 32 GPs who owned a general practice were interviewed. Three main topic areas were covered in the interviews: the decision-making process in the organisation, considerations and arguments to train and employ a PA/NP, and the tasks and responsibilities of a PA/NP. Employment of PAs/NPs in out-of-hours services was intended to substitute care for minor ailments in order to decrease GPs' caseload or to increase service capacity. Mangers formulated long-term planning and role definitions when changing workforce skill mix. Lastly, out-of-hours services experienced difficulties with creating team support among their members regarding the employment of PAs/NPs. In general practices during office hours, GPs indented both substitution and supplementation for minor ailments and/or target populations through changing the skill mix. Supplementation was aimed at improving quality of care and extending the range of services to patients. The decision-making in general practices was accompanied with little planning and role definition. The willingness to employ PAs/NPs was highly influenced by an employees' motivation to start the master's programme and GPs' prior experience with PAs/NPs. Knowledge about the PA/NP profession and legislations was often lacking. Role standardisations, long-term political planning and support from professional associations are needed to support policy makers in implementing skill mix in primary care.
ERIC Educational Resources Information Center
Kocman, Andreas; Fischer, Linda; Weber, Germain
2018-01-01
Background: Obtaining employment is among the most important ambitions of people with intellectual disability. Progress towards comprehensive inclusive employment is hampered by numerous barriers. Limited research is available on these barriers and strategies to overcome them. Method: A mixed method approach in a sample of 30 HR-managers was used…
ERIC Educational Resources Information Center
Lai, Manhong; Du, Ping; Lo, Leslie N. K.
2016-01-01
This study investigates changes to academic work life under recent employment reform in the Chinese Mainland. It employs a mixed-methods research approach, first conducting a survey of 1,770 teachers at nine universities in Mainland China. These nine universities consist of first-tier, second-tier, and ordinary universities. Next, through a…
Factors Affecting the Unemployment (Rate) of Female Art Graduates in Iran
ERIC Educational Resources Information Center
Hedayat, Mina; Kahn, Sabzali Musa; Hanafi, Jaffri
2013-01-01
The aim of this study is to explore the relationship between the opportunities of female artist graduates in Tehran Province and the current employment market. Mixed method was employed in this study. The population of the current study consisted of 240 female artist graduates selected using a systematic random sampling method from both public and…
ERIC Educational Resources Information Center
Awsumb, Jessica M.
2017-01-01
This study examines post-school outcomes of youth with disabilities that were served by the Illinois vocational rehabilitation (VR) agency while in Chicago Public Schools (CPS) through a mixed methodology research design. In order to understand how outcomes differ among the study population, a large-scale dataset of the employment outcomes of…
Rating Scale Impact on EFL Essay Marking: A Mixed-Method Study
ERIC Educational Resources Information Center
Barkaoui, Khaled
2007-01-01
Educators often have to choose among different types of rating scales to assess second-language (L2) writing performance. There is little research, however, on how different rating scales affect rater performance. This study employed a mixed-method approach to investigate the effects of two different rating scales on EFL essay scores, rating…
"...But that's Just the Stereotype": Gender and Ethnicity in Transition to Adulthood
ERIC Educational Resources Information Center
Basit, Tehmina N.
2012-01-01
This article examines the role of gender and ethnicity in young minority ethnic British citizens' transition to adulthood. As part of a larger study using a mixed methods approach, in-depth interviews were conducted with 20 young men and women aged 14-24 at different stages of education, employment and non-employment. By employing Bourdieu's…
ERIC Educational Resources Information Center
Ma, Wen; Wang, Chuang
2012-01-01
International students in the United States often employ culture-specific learning strategies to help them improve their proficiency in English. This study explored the use of self-regulated strategies by 49 Chinese graduate students from 24 fields of study at three universities in the Northeast. The research used the mixed survey method to…
ERIC Educational Resources Information Center
Lai, Manhong; Du, Ping; Li, Linlin
2014-01-01
In order to raise the international reputation and quality of higher education in "China", the Ministry of Education initiated new university employment reform, which pressed academics to produce more research. Recent employment reform has aggravated the conflict between teaching and research. This study "uses" mixed methods to…
Östlund, Ulrika; Kidd, Lisa; Wengström, Yvonne; Rowa-Dewar, Neneh
2011-03-01
It has been argued that mixed methods research can be useful in nursing and health science because of the complexity of the phenomena studied. However, the integration of qualitative and quantitative approaches continues to be one of much debate and there is a need for a rigorous framework for designing and interpreting mixed methods research. This paper explores the analytical approaches (i.e. parallel, concurrent or sequential) used in mixed methods studies within healthcare and exemplifies the use of triangulation as a methodological metaphor for drawing inferences from qualitative and quantitative findings originating from such analyses. This review of the literature used systematic principles in searching CINAHL, Medline and PsycINFO for healthcare research studies which employed a mixed methods approach and were published in the English language between January 1999 and September 2009. In total, 168 studies were included in the results. Most studies originated in the United States of America (USA), the United Kingdom (UK) and Canada. The analytic approach most widely used was parallel data analysis. A number of studies used sequential data analysis; far fewer studies employed concurrent data analysis. Very few of these studies clearly articulated the purpose for using a mixed methods design. The use of the methodological metaphor of triangulation on convergent, complementary, and divergent results from mixed methods studies is exemplified and an example of developing theory from such data is provided. A trend for conducting parallel data analysis on quantitative and qualitative data in mixed methods healthcare research has been identified in the studies included in this review. Using triangulation as a methodological metaphor can facilitate the integration of qualitative and quantitative findings, help researchers to clarify their theoretical propositions and the basis of their results. This can offer a better understanding of the links between theory and empirical findings, challenge theoretical assumptions and develop new theory. Copyright © 2010 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Murray, Laura Carolyn
2017-01-01
This dissertation study employs an exploratory sequential mixed methods design to investigate how emerging adults with psychiatric disabilities plan for and transition to and through college. Special attention is paid to how disclosure of disability status in educational contexts can influence both educational and recovery outcomes. Though more…
ERIC Educational Resources Information Center
Gu, Jiangyue
2016-01-01
Epistemic beliefs are individuals' beliefs about the nature of knowledge, how knowledge is constructed, and how knowledge can be justified. This study employed a mixed-methods approach to examine: (a) middle and high school students' self-reported epistemic beliefs (quantitative) and epistemic beliefs revealed from practice (qualitative) during a…
ERIC Educational Resources Information Center
Ferguson, Kristin M.; Bender, Kimberly; Thompson, Sanna J.; Maccio, Elaine M.; Pollio, David
2012-01-01
This mixed-methods study identified correlates of unemployment among homeless young adults in five cities. Two hundred thirty-eight homeless young people from Los Angeles (n = 50), Austin (n = 50), Denver (n = 50), New Orleans (n = 50), and St. Louis (n = 38) were recruited using comparable sampling strategies. Multivariate logistic regression…
ERIC Educational Resources Information Center
Corbett, Erin S.
2017-01-01
While recent research has focused on the relationship between educational attainment and recidivism for formerly incarcerated persons, less research has focused on the relationship between educational attainment/level and employment. This study employed mixed methods to examine data on post-release employment outcomes for ex-offenders from, and…
Holistic Initiatives for Enhancing Graduate Employability in Zimbabwe
ERIC Educational Resources Information Center
Garwe, Evelyn Chiyevo
2014-01-01
The objective of the study was to document initiatives for enhancing graduate employability and building successful future careers for students. The author used the case of Zimbabwe to explore interventions by higher education institutions, government, industry and commerce as well as professional bodies. The methodology involved a mix of…
Experiences of Paraprofessionals in US Preschool Special Education and General Education Classrooms
ERIC Educational Resources Information Center
Brown, Tiara Saufley; Stanton-Chapman, Tina L.
2017-01-01
A substantial challenge confronting public education systems across the world is the employment and retention of high-quality paraprofessionals (also known as teaching assistants and educational assistants). The current study expands upon previous research by employing a mixed methods design to examine the relationship between paraprofessionals'…
ERIC Educational Resources Information Center
Harwood, Debra; Tukonic, Stephanie
2016-01-01
Self-constructed perceptions of early childhood educator professionalism were explored in a small-scale mixed-method survey using convenience sampling. Fifty-four educators in Ontario, Canada participated in the study and shared their views related to professionalism. A mixed-methodology was employed using an electronic questionnaire composed of…
Strategies Pregnant Rural Women Employ to Deal with Intimate Partner Violence
ERIC Educational Resources Information Center
Bhandari, Shreya; Bullock, Linda F. C.; Sharps, Phyllis W.
2013-01-01
This study explored strategies from the Intimate Partner Violence Strategy Index (IPVSI) that a sub-set of 20 rural, low-income, abused women of a larger, multi-site, mixed-method study employed to deal with Intimate Partner Violence (IPV) during the perinatal period. We conducted 32 in-depth interviews with women who were pregnant (N = 12) and/or…
Thermodynamic calculations of oxygen self-diffusion in mixed-oxide nuclear fuels
Parfitt, David C.; Cooper, Michael William; Rushton, Michael J.D.; ...
2016-07-29
Mixed-oxide fuels containing uranium with thorium and/or plutonium may play an important part in future nuclear fuel cycles. There are, however, significantly less data available for these materials than conventional uranium dioxide fuel. In the present study, we employ molecular dynamics calculations to simulate the elastic properties and thermal expansivity of a range of mixed oxide compositions. These are then used to support equations of state and oxygen self-diffusion models to provide a self-consistent prediction of the behaviour of these mixed oxide fuels at arbitrary compositions.
Transverse mixing of ellipsoidal particles in a rotating drum
NASA Astrophysics Data System (ADS)
He, Siyuan; Gan, Jieqing; Pinson, David; Zhou, Zongyan
2017-06-01
Rotating drums are widely used in industry for mixing, milling, coating and drying processes. In the past decades, mixing of granular materials in rotating drums has been extensively investigated, but most of the studies are based on spherical particles. Particle shape has an influence on the flow behaviour and thus mixing behaviour, though the shape effect has as-yet received limited study. In this work, discrete element method (DEM) is employed to study the transverse mixing of ellipsoidal particles in a rotating drum. The effects of aspect ratio and rotating speed on mixing quality and mixing rate are investigated. The results show that mixing index increases exponentially with time for both spheres and ellipsoids. Particles with various aspect ratios are able to reach well-mixed states after sufficient revolutions in the rolling or cascading regime. Ellipsoids show higher mixing rate when rotational speed is set between 25 and 40 rpm. The relationship between mixing rate and aspect ratio of ellipsoids is established, demonstrating that, particles with aspect ratios of 0.5 and 2.0 achieve the highest mixing rates. Increasing rotating speed from 15 rpm to 40 rpm does not necessarily increase the mixing speed of spheres, while monotonous increase is observed for ellipsoids.
ERIC Educational Resources Information Center
Riebe, L.; Sibson, R.; Roepen, D.; Meakins, K.
2013-01-01
This study provides insights into the perceptions and expectations of Australian undergraduate business students (n=150) regarding the incorporation of guest speakers into the curriculum of a leadership unit focused on employability skills development. The authors adopted a mixed methods approach. A survey was conducted, with quantitative results…
An Inquiry into the Development of Future Speech-Language Pathologists: A Mixed Methods Study
ERIC Educational Resources Information Center
Plotts, Kimberly P.
2017-01-01
Upon graduating college, many students seek employment within the degree area in which they obtained. Employers are seeking skills in individuals that encompass interpersonal, technical, analytical, personal, and professional abilities. As with many careers, the allied health field requires content specific knowledge and specialized skills, which…
Human Service Administrator Perceptions of Online MSW Degree Programs
ERIC Educational Resources Information Center
Curran, Laura; Sanchez Mayers, Ray; Fulghum, Fontaine
2017-01-01
Online programs have proliferated rapidly in higher education, and this reality holds true for social work education as well. Employing a mixed methods design, this study looked at employer perceptions of online degrees compared to traditional degrees. Data was collected through an online survey that included Likert type and open-ended questions…
Cultural Capital, Family Background and Education: Choosing University Subjects in China
ERIC Educational Resources Information Center
Sheng, Xiaoming
2017-01-01
This article employs Bourdieu's conceptual tools to unpack family influences on students' subject and university choices in China. This empirical study employed mixed research approaches, using both quantitative and qualitative methods, to examine students' choices of subjects and universities in a sample of secondary school students from the age…
ERIC Educational Resources Information Center
Thomson, Margareta Maria
2013-01-01
This study explored the U.S. prospective teachers' motivations for teaching, teaching goal development, and views of their commitment to teaching. A sequential explanatory mixed-methods design was employed. Participants (N = 61) completed a survey in which they rated the importance of various factors in their teaching career choice. Furthermore,…
Code of Federal Regulations, 2011 CFR
2011-04-01
... EMPLOYMENT OPPORTUNITY; POLICY, PROCEDURES AND PROGRAMS Equal Employment Opportunity Without Regard to Race... and the time frames for executing the right to request an administrative hearing. Note: Where a mixed... unless the MSPB has dismissed the mixed case complaint or appeal for jurisdictional reasons. (See 29 CFR...
Code of Federal Regulations, 2010 CFR
2010-04-01
... EMPLOYMENT OPPORTUNITY; POLICY, PROCEDURES AND PROGRAMS Equal Employment Opportunity Without Regard to Race... and the time frames for executing the right to request an administrative hearing. Note: Where a mixed... unless the MSPB has dismissed the mixed case complaint or appeal for jurisdictional reasons. (See 29 CFR...
Murray, Peter D; Dobbels, Fabienne; Lonsdale, Daniel C; Harden, Paul N
2014-10-01
Young adult kidney patients are at an important stage of development when end-stage kidney disease (ESKD) may adversely influence progress in education and employment. This study is designed to assess the impact of ESKD on education and employment outcomes in young adults. This cross-sectional study was a mixed methods design. Education and career achievements in young adults with ESKD were recorded quantitatively using a questionnaire survey (n = 57): 14 of 57 representative participants were subsequently selected for semistructured interview. Questionnaire survey was conducted in 57 young adults (median age 25): 8.8% (n = 5) were predialysis; 14.0% (n = 8) dialysis; and 78.9% (n = 45) were kidney transplant recipients. Median school-leaving age was 16 (interquartile range = 15-19). Of 57 young adults, 10 (17.5%) were still studying, 43 (75.4%) had completed education, 34 (59.7%) were employed (23 full time and 11 part time), and 19 (33.3%) were unemployed. Twenty-seven of 45 transplanted patients were employed (60.0%). Of these 27, 21 were full time (77.8%). Five of eight dialysis patients were employed: only one of eight was full-time employed (12.5%). Themes impacting on education and employment included low energy levels, time missed, loss of self-esteem, and feelings of loneliness and isolation, which may progress to depression and recreational drug use. Lack of understanding from educators and employers resulting in lost work, and career ambitions changed or limited because of dialysis. Dialysis has a major negative impact on education and reduced employment rates of young adults. There is a general lack of understanding among educators and employers of the impact of ESKD. Low energy levels, lack of self-esteem, and depression are key factors. There is a need for health care providers to recognize this issue and invest in supporting young adults with ESKD. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Initial steps toward automation of a propellant processor
NASA Technical Reports Server (NTRS)
Schallhorn, Paul; Ramohalli, Kumar
1990-01-01
This paper presents the results from an experimental study aimed at ultimately automating the mixing of propellants in order to minimize unintended variations usually attributed to human error. The water heater and delivery system of a one-pint Baker-Perkins (APV) vertical mixer are automated with computer control. Various innovations are employed to introduce economy and low thermal inertia. Some of these include twin heaters/reservoirs instead of one large reservoir, a compact water mixer for achieving the desired temperature quickly, and thorough insulation of the entire water system. The completed system is tested during two propellant mixes. The temperature uniformly is proven through careful measurements employing several local thermocouples.
NASA Astrophysics Data System (ADS)
Lalitha, P. V.; Ramaswamy, R.; Ramakrishnan, Geetha; Rao, P. Sambasiva
1994-12-01
The oscillatory behaviour of three substrates, ortho-vanillin, para-vanillin and adrenaline, in mixed media (water plus 20% acetonitrile) has been investigated using EPR and EMF techniques. All these substrates exhibit two types of oscillation involving Br 2/Br - and Mn(III)/Mn(II) redox couples. From the oscillatory characteristics (total time, number of oscillations and time per oscillation) obtained by employing these techniques, the reactivities of the vanillins have been correlated. The Field—Koros—Noyes mechanism, suggested for catalysed systems in pure aqueous medium, is established to be applicable even in mixed media.
Measurement of Employability Skills on Teaching Factory Learning
NASA Astrophysics Data System (ADS)
Subekti, S.; Ana, A.
2018-02-01
Vocational High Schools as one of the educational institutions that has the responsibility in preparing skilled labors has a challenge to improve the quality of human resources as a candidate for skilled labors, to compete and survive in a changing climate of work. BPS noted an increase in the number of non-worker population (BAK) in 2015-2017 on vocational graduates as many as 564,272 people. The ability to adapt and maintain jobs in a variety of conditions is called employability skills. This study purpose to measure the development of employability skills of communication skills, problem-solving skills and teamwork skills on the implementation of teaching factory learning in SMK Negeri 1 Cibadak, THPH Skills Program on bakery competency. This research uses mixed method, with concurrent triangulation mix methods research design. Data collection techniques used interviews and questionnaires. The result shows that there are increasing students’ employability skills in communication skills, problem solving skills, and teamwork skills in teaching factory learning. Principles of learning that apply learning by doing student centering and learning arrangements such as situations and conditions in the workplace have an impact on improving student employability skills.
Fluid flow and fuel-air mixing in a motored two-dimensional Wankel rotary engine
NASA Technical Reports Server (NTRS)
Shih, T. I.-P.; Nguyen, H. L.; Stegeman, J.
1986-01-01
The implicit-factored method of Beam and Warming was employed to obtain numerical solutions to the conservation equations of mass, species, momentum, and energy to study the unsteady, multidimensional flow and mixing of fuel and air inside the combustion chambers of a two-dimensional Wankel rotary engine under motored conditions. The effects of the following engine design and operating parameters on fluid flow and fuel-air mixing during the intake and compression cycles were studied: engine speed, angle of gaseous fuel injection during compression cycle, and speed of the fuel leaving fuel injector.
Fluid flow and fuel-air mixing in a motored two-dimensional Wankel rotary engine
NASA Astrophysics Data System (ADS)
Shih, T. I.-P.; Nguyen, H. L.; Stegeman, J.
1986-06-01
The implicit-factored method of Beam and Warming was employed to obtain numerical solutions to the conservation equations of mass, species, momentum, and energy to study the unsteady, multidimensional flow and mixing of fuel and air inside the combustion chambers of a two-dimensional Wankel rotary engine under motored conditions. The effects of the following engine design and operating parameters on fluid flow and fuel-air mixing during the intake and compression cycles were studied: engine speed, angle of gaseous fuel injection during compression cycle, and speed of the fuel leaving fuel injector.
ERIC Educational Resources Information Center
Stott, Tim; Zaitseva, Elena; Cui, Vanessa
2014-01-01
This four-year mixed method longitudinal study utilises data collected from four cohorts of Outdoor Education (OE) students to compare "fresher" and "graduate" identities and to explore the impact of identity on graduate employment. Findings demonstrate that compared to other programmes, and the university as a whole, OE…
The Complexities of Family Caregiving at Work: A Mixed-Methods Study.
Gaugler, Joseph E; Pestka, Deborah L; Davila, Heather; Sales, Rebecca; Owen, Greg; Baumgartner, Sarah A; Shook, Rocky; Cunningham, Jane; Kenney, Maureen
2018-01-01
The current project examined the impact of caregiving and caregiving-work conflict on employees' well-being. A sequential explanatory mixed-methods design (QUAN→qual) was utilized, and a total of 880 employees from a large health-care plan employer completed an online survey. Forty-five caregivers who completed the survey also participated in one of the five focus groups held 1 to 2 months later. Employed caregivers were significantly ( p < .05) more likely to indicate poorer physical and mental health than noncaregivers; among caregivers ( n = 370), caregiving-work conflict emerged as the most significant predictor of well-being and fully mediated the empirical relationship between burden and well-being. The focus group findings complemented the quantitative results; many of the challenges employed caregivers experience stem from their ability or inability to effectively balance their employment and caregiving roles. The results suggest the need to focus on caregiving-work conflict when constructing new or translating existing evidence-based caregiver interventions.
ERIC Educational Resources Information Center
Huang, SuHua
2015-01-01
A mixed-method embedded research design was employed to investigate the effectiveness of the integration of technology for second-grade students' vocabulary development and learning. Two second-grade classes with a total of 40 students (21 boys and 19 girls) were randomly selected to participate in this study for the course of a semester. One…
2012-01-01
Background Stigma and discrimination present an important barrier to finding and keeping work for individuals with a mental health problem. This paper reviews evidence on: 1) employment-related disclosure beliefs and behaviours of people with a mental health problem; 2) factors associated with the disclosure of a mental health problem in the employment setting; 3) whether employers are less likely to hire applicants who disclose a mental health problem; and 4) factors influencing employers' hiring beliefs and behaviours towards job applicants with a mental health problem. Methods A systematic review was conducted for the period 1990-2010, using eight bibliographic databases. Meta-ethnography was used to provide a thematic understanding of the disclosure beliefs and behaviours of individuals with mental health problem. Results The searches yielded 8,971 items which was systematically reduced to 48 included studies. Sixteen qualitative, one mixed methods and seven quantitative studies were located containing evidence on the disclosure beliefs and behaviours of people with a mental health problem, and the factors associated with these beliefs and behaviours. In the meta-ethnography four super-ordinate themes were generated: 1) expectations and experiences of discrimination; 2) other reasons for non-disclosure; 3) reasons for disclosure; and 4) disclosure dimensions. Two qualitative, one mixed methods and 22 quantitative studies provided data to address the remaining two questions on the employers perspective. Conclusions By presenting evidence from the perspective of individuals on both sides of the employment interaction, this review provides integrated perspective on the impact of disclosure of a mental health problem on employment outcomes. PMID:22339944
Brohan, Elaine; Henderson, Claire; Wheat, Kay; Malcolm, Estelle; Clement, Sarah; Barley, Elizabeth A; Slade, Mike; Thornicroft, Graham
2012-02-16
Stigma and discrimination present an important barrier to finding and keeping work for individuals with a mental health problem. This paper reviews evidence on: 1) employment-related disclosure beliefs and behaviours of people with a mental health problem; 2) factors associated with the disclosure of a mental health problem in the employment setting; 3) whether employers are less likely to hire applicants who disclose a mental health problem; and 4) factors influencing employers' hiring beliefs and behaviours towards job applicants with a mental health problem. A systematic review was conducted for the period 1990-2010, using eight bibliographic databases. Meta-ethnography was used to provide a thematic understanding of the disclosure beliefs and behaviours of individuals with mental health problem. The searches yielded 8,971 items which was systematically reduced to 48 included studies. Sixteen qualitative, one mixed methods and seven quantitative studies were located containing evidence on the disclosure beliefs and behaviours of people with a mental health problem, and the factors associated with these beliefs and behaviours. In the meta-ethnography four super-ordinate themes were generated: 1) expectations and experiences of discrimination; 2) other reasons for non-disclosure; 3) reasons for disclosure; and 4) disclosure dimensions. Two qualitative, one mixed methods and 22 quantitative studies provided data to address the remaining two questions on the employers perspective. By presenting evidence from the perspective of individuals on both sides of the employment interaction, this review provides integrated perspective on the impact of disclosure of a mental health problem on employment outcomes.
Realism and Pragmatism in a mixed methods study.
Allmark, Peter; Machaczek, Katarzyna
2018-06-01
A discussion of how adopting a Realist rather than Pragmatist methodology affects the conduct of mixed methods research. Mixed methods approaches are now extensively employed in nursing and other healthcare research. At the same time, realist methodology is increasingly used as philosophical underpinning of research in these areas. However, the standard philosophical underpinning of mixed methods research is Pragmatism, which is generally considered incompatible or at least at odds with Realism. This paper argues that Realism can be used as the basis of mixed methods research and that doing so carries advantages over using Pragmatism. A mixed method study into patient handover reports is used to illustrate how Realism affected its design and how it would have differed had a Pragmatist approach been taken. Discussion Paper. Philosophers Index; Google Scholar. Those undertaking mixed methods research should consider the use of Realist methodology with the addition of some insights from Pragmatism to do with the start and end points of enquiry. Realism is a plausible alternative methodology for those undertaking mixed methods studies. © 2018 John Wiley & Sons Ltd.
A Mixed Methods Content Analysis of the Research Literature in Science Education
NASA Astrophysics Data System (ADS)
Schram, Asta B.
2014-10-01
In recent years, more and more researchers in science education have been turning to the practice of combining qualitative and quantitative methods in the same study. This approach of using mixed methods creates possibilities to study the various issues that science educators encounter in more depth. In this content analysis, I evaluated 18 studies from science education journals as they relate to the definition, design, and overall practice of using mixed methods. I scrutinized a purposeful sample, derived from 3 journals (the International Journal of Science Education, the Journal of Research in Science Teaching, and the Research in Science Education) in terms of the type of data collected, timing, priority, design, the mixing of the 2 data strands in the studies, and the justifications authors provide for using mixed methods. Furthermore, the articles were evaluated in terms of how well they met contemporary definitions for mixed methods research. The studies varied considerably in the use and understanding of mixed methods. A systematic evaluation of the employment of mixed methods methodology was used to identify the studies that best reflected contemporary definitions. A comparison to earlier content analyses of mixed methods research indicates that researchers' knowledge of mixed methods methodology may be increasing. The use of this strategy in science education research calls, however, for an improved methodology, especially concerning the practice of mixing. Suggestions are given on how to best use this approach.
NASA Astrophysics Data System (ADS)
Chen, Jia; An, Chunsheng; Chen, Hong
2018-02-01
We investigate mixing of the lowest-lying qqq configurations with JP = 1/2- caused by the hyperfine interactions between quarks mediated by Goldstone Boson Exchange, One Gluon Exchange, and both Goldstone Boson and One Gluon exchange, respectively. The first orbitally excited nucleon, Σ, Λ and Ξ states are considered. Contributions of both the contact term and tensor term are taken into account. Our numerical results show that mixing of the studied configurations in the two employed hyperfine interaction models are very different. Therefore, the present results, which should affect the strong and electromagnetic decays of baryon resonances, may be used to examine the present employed hyperfine interaction models. Supported by National Natural Science Foundation of China (11675131,11645002), Chongqing Natural Science Foundation (cstc2015jcyjA00032) and Fundamental Research Funds for the Central Universities (SWU115020)
29 CFR 1910.426 - Mixed-gas diving.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 29 Labor 5 2014-07-01 2014-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified. (b) Limits. Mixed-gas diving shall be conducted only when: (1) A...
29 CFR 1910.426 - Mixed-gas diving.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 29 Labor 5 2012-07-01 2012-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified. (b) Limits. Mixed-gas diving shall be conducted only when: (1) A...
29 CFR 1910.426 - Mixed-gas diving.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 29 Labor 5 2013-07-01 2013-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified. (b) Limits. Mixed-gas diving shall be conducted only when: (1) A...
29 CFR 1910.426 - Mixed-gas diving.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 29 Labor 5 2011-07-01 2011-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified. (b) Limits. Mixed-gas diving shall be conducted only when: (1) A...
Hayat, Tasawar; Nawaz, Sadaf; Alsaedi, Ahmed; Rafiq, Maimona
2016-01-01
Main objective of present study is to analyze the mixed convective peristaltic transport of water based nanofluids using five different nanoparticles i.e. (Al2O3, CuO, Cu, Ag and TiO2). Two thermal conductivity models namely the Maxwell's and Hamilton-Crosser's are used in this study. Hall and Joule heating effects are also given consideration. Convection boundary conditions are employed. Furthermore, viscous dissipation and heat generation/absorption are used to model the energy equation. Problem is simplified by employing lubrication approach. System of equations are solved numerically. Influence of pertinent parameters on the velocity and temperature are discussed. Also the heat transfer rate at the wall is observed for considered five nanofluids using the two phase models via graphs. PMID:27104596
How old is old in allegations of age discrimination? The limitations of existing law.
Wiener, Richard L; Farnum, Katlyn S
2016-10-01
Under Title VII, courts may give a mixed motive instruction allowing jurors to determine that defendants are liable for discrimination if an illegal factor (here: race, color, religion, sex, or national origin) contributed to an adverse decision. Recently, the Supreme Court held that to conclude that an employer discriminated against a worker because of age, the Age Discrimination in Employment Act, unlike Title VII of the Civil Rights Act of 1964, requires "but for" causality, necessitating jurors to find that age was the determinative factor in an employer's adverse decision regarding that worker. Using a national online sample (N = 392) and 2 study phases, 1 to measure stereotypes, and a second to present experimental manipulations, this study tested whether older worker stereotypes as measured through the lens of the Stereotype Content Model, instruction type (but for vs. mixed motive causality), and plaintiff age influenced mock juror verdicts in an age discrimination case. Decision modeling in Phase 2 with 3 levels of case orientation (i.e., proplaintiff, prodefendant, and neutral) showed that participants relied on multiple factors when making a decision, as opposed to just 1, suggesting that mock jurors favor a mixed model approach to discrimination verdict decisions. In line with previous research, instruction effects showed that mock jurors found in favor of plaintiffs under mixed motive instructions but not under "but for" instructions especially for older plaintiffs (64- and 74-year-old as opposed to 44- and 54-year-old-plaintiffs). Most importantly, in accordance with the Stereotype Content Model theory, competence and warmth stereotypes moderated the instruction effects found for specific judgments. The results of this study show the importance of the type of legal causality required for age discrimination cases. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
ERIC Educational Resources Information Center
Huang, SuHua
2012-01-01
The mixed-method explanatory research design was employed to investigate the effectiveness of the Accelerated Reader (AR) program on middle school students' reading achievement and motivation. A total of 211 sixth to eighth-grade students provided quantitative data by completing an AR Survey. Thirty of the 211 students were randomly selected to…
ERIC Educational Resources Information Center
Heard, Courtney Christian Charisse
2013-01-01
The purpose of this study was to assess the sex-role egalitarian attitudes and gender role socialization experiences of African American men and women. A sequential mixed-methods design was employed to research this phenomenon. The Sex-Role Egalitarianism Scale-Short Form BB (SRES-BB) was utilized to assess sex-role egalitarian attitudes (King…
Bunkar, Durga Shankar; Jha, Alok; Mahajan, Ankur
2014-10-01
The objective of this study was to optimize the process of manufacturing instant kheer mix based on pearl millet instead of rice. Dairy whitener, pearl millet and powdered sugar were the responses studied by employing the 3-factor Central Composite Rotatable Design. The formulation with 15 g sugar, 30 g dairy whitener and 20 g pearl millet was found suitable for obtaining dry kheer mix. The analyses were based on scores of consistency, cohesiveness, viscosity and overall acceptability. The reconstituted product from the formulated kheer mix had an overall acceptability score of 7.66 and desirability index of 0.7663. The moisture, fat, protein, carbohydrate and ash contents of the dry mix product were 2.8, 4.38, 5.84, 85.88 and 1.1 %, respectively.
ERIC Educational Resources Information Center
Ipsen, Catherine; Swicegood, Grant
2015-01-01
Purpose: To examine rural and urban differences in Vocational Rehabilitation (VR) case mix, delivery practices, and employment outcomes. Methods: Rehabilitation Services Administration 911 (RSA-911) case data do not include location indicators that allow for rural analyses. We compiled RSA-911 data with county and ZIP code information from 47 VR…
Kocman, Andreas; Fischer, Linda; Weber, Germain
2018-01-01
Obtaining employment is among the most important ambitions of people with intellectual disability. Progress towards comprehensive inclusive employment is hampered by numerous barriers. Limited research is available on these barriers and strategies to overcome them. A mixed method approach in a sample of 30 HR-managers was used to assess (i) differences in perceived barriers for employment of people with specific disabilities and mental disorders; (ii) barriers specific to employing people with intellectual disability; (iii) strategies to overcome these barriers. Employers perceive more barriers for hiring people with intellectual disability and mental disorders than for physical disabilities. Employment for this population is hampered by a perceived lack of skills and legal issues. Strategies perceived as beneficial are supplying information, changes in organizational strategies and legal changes. Employers' differentiated expectations and reservations towards hiring individuals with specific disabilities need to be taken into account to increase employment for people with intellectual disability. © 2017 John Wiley & Sons Ltd.
0-6613 : evaluate binder and mixture aging for warm mix asphalt.
DOT National Transportation Integrated Search
2013-08-01
Warm mix asphalt (WMA) technologies employ reduced : mixing and placement temperatures, thereby allowing : reduced fuel consumption, enhanced compaction, : increased haul distances, and an extended paving : season. However, there have been issues of ...
Two-species mixing in a nested Penning trap for antihydrogen trapping
NASA Astrophysics Data System (ADS)
Ordonez, C. A.; Weathers, D. L.
2008-08-01
There exists an international quest to trap neutral antimatter in the form of antihydrogen for scientific study. One method that is being developed for trapping antihydrogen employs a nested Penning trap. Such a trap serves to mix positrons and antiprotons so as to produce low energy antihydrogen atoms. Mixing is achieved when the confinement volumes of the two species overlap one another. In the work presented here, a theoretical understanding of the mixing process is developed by analyzing a mixing scheme that was recently reported [G. Gabrielse et al., Phys. Rev. Lett. 100, 113001 (2008)]. The results indicate that positron space charge or collisions among antiprotons may substantially reduce the fraction of antiprotons that have an energy suitable for antihydrogen trapping.
Pacific deep circulation and ventilation controlled by tidal mixing away from the sea bottom.
Oka, Akira; Niwa, Yoshihiro
2013-01-01
Vertical mixing in the ocean is a key driver of the global ocean thermohaline circulation, one of the most important factors controlling past and future climate change. Prior observational and theoretical studies have focused on intense tidal mixing near the sea bottom (near-field mixing). However, ocean general circulation models that employ a parameterization of near-field mixing significantly underestimate the strength of the Pacific thermohaline circulation. Here we demonstrate that tidally induced mixing away from the sea bottom (far-field mixing) is essential in controlling the Pacific thermohaline circulation. Via the addition of far-field mixing to a widely used tidal parameterization, we successfully simulate the Pacific thermohaline circulation. We also propose that far-field mixing is indispensable for explaining the presence of the world ocean's oldest water in the eastern North Pacific Ocean. Our findings suggest that far-field mixing controls ventilation of the deep Pacific Ocean, a process important for ocean carbon and biogeochemical cycles.
Quantification of chaotic strength and mixing in a micro fluidic system
NASA Astrophysics Data System (ADS)
Kim, Ho Jun; Beskok, Ali
2007-11-01
Comparative studies of five different techniques commonly employed to identify the chaotic strength and mixing efficiency in micro fluidic systems are presented to demonstrate the competitive advantages and shortcomings of each method. The 'chaotic electroosmotic stirrer' of Qian and Bau (2002 Anal. Chem. 74 3616-25) is utilized as the benchmark case due to its well-defined flow kinematics. Lagrangian particle tracking methods are utilized to study particle dispersion in the conceptual device using spectral element and fourth-order Runge-Kutta discretizations in space and time, respectively. Stirring efficiency is predicted using the stirring index based on the box counting method, and Poincaré sections are utilized to identify the chaotic and regular regions under various actuation conditions. Finite time Lyapunov exponents are calculated to quantify the chaotic strength, while the probability density function of the stretching field is utilized as an alternative method to demonstrate the statistical analysis of chaotic and partially chaotic cases. Mixing index inverse, based on the standard deviation of scalar species distribution, is utilized as a metric to quantify the mixing efficiency. Series of numerical simulations are performed by varying the Peclet number (Pe) at fixed kinematic conditions. The mixing time (tm) is characterized as a function of the Pe number, and tm ~ ln(Pe) scaling is demonstrated for fully chaotic cases, while tm ~ Peα scaling with α ≈ 0.33 and α = 0.5 are observed for partially chaotic and regular cases, respectively. Employing the aforementioned techniques, optimum kinematic conditions and the actuation frequency of the stirrer that result in the highest mixing/stirring efficiency are identified.
Adler, Adir; Ben-Ari, Adital
2018-01-01
Until recently, the literature that addressed the phenomenon of mixed-orientation relationships, in which the female partner is straight and the male partner is non-straight, has focused mainly on the men's perspective. Most of the studies have employed a pessimistic tone, underscoring the obstacles faced by each of the partners. This study was designed to understand how women of mixed-orientation relationships construct their reality within such a relationship, focusing on elements that assist them in maintaining those relationships. Based on the phenomenological paradigm, in-depth interviews with eight women in mixed-orientation relationships were conducted. The findings indicate that in order to adapt to their newly constructed reality, women reframe various individual, marital, and social aspects in their lives. Those reframing processes constituted a point of departure to developing a conceptual model, which outlines the journey to reality reconstruction among women in mixed-orientation relationships.
12 CFR 268.302 - Mixed case complaints.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Mixed case complaints. 268.302 Section 268.302... RULES REGARDING EQUAL OPPORTUNITY Related Processes § 268.302 Mixed case complaints. A mixed case complaint is a complaint of employment discrimination filed with the Board based on race, color, religion...
12 CFR 268.302 - Mixed case complaints.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Mixed case complaints. 268.302 Section 268.302... RULES REGARDING EQUAL OPPORTUNITY Related Processes § 268.302 Mixed case complaints. A mixed case complaint is a complaint of employment discrimination filed with the Board based on race, color, religion...
29 CFR 1910.426 - Mixed-gas diving.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 5 2010-07-01 2010-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Specific Operations Procedures § 1910.426 Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following...
ERIC Educational Resources Information Center
Koenig, Lane; Fields, Errol L.; Dall, Timothy M.; Ameen, Ansari Z.; Harwood, Henrick J.
This report demonstrates three applications of case-mix methods using regression analysis. The results are used to assess the relative effectiveness of substance abuse treatment providers. The report also examines the ability of providers to improve client employment outcomes, an outcome domain relatively unexamined in the assessment of provider…
Implementation of Evidence-Based Employment Services in Specialty Mental Health
Hamilton, Alison B; Cohen, Amy N; Glover, Dawn L; Whelan, Fiona; Chemerinski, Eran; McNagny, Kirk P; Mullins, Deborah; Reist, Christopher; Schubert, Max; Young, Alexander S
2013-01-01
Objective. Study a quality improvement approach for implementing evidence-based employment services at specialty mental health clinics. Data Sources/Study Setting. Semistructured interviews with clinicians and administrators before, during, and after implementation. Qualitative field notes, structured baseline and follow-up interviews with patients, semistructured interviews with patients after implementation, and administrative data. Study Design. Site-level controlled trial at four implementation and four control sites. Hybrid implementation–effectiveness study with mixed methods intervention evaluation design. Data Collection/Extraction Methods. Site visits, in-person and telephone interviews, patient surveys, patient self-assessment. A total of 801 patients completed baseline surveys and 53 clinicians and other clinical key stakeholders completed longitudinal qualitative interviews. Principal Findings. At baseline, sites varied in the availability, utilization, and quality of supported employment. Each site needed quality improvement for this service, though for differing reasons, with some needing development of the service itself and others needing increased service capacity. Improvements in knowledge, attitudes, beliefs, and referral behaviors were evident in mid- and postimplementation interviews, though some barriers persisted. Half of patients expressed an interest in working at baseline. Patients at implementation sites were 2.3 times more likely to receive employment services during the study year. Those who had a service visit were more likely to be employed at follow-up than those who did not. Conclusions. Studies of implementation and effectiveness require mixed methods to both enhance implementation in real time and provide context for interpretation of complex results. In this study, a quality improvement approach resulted in superior patient-level outcomes and improved clinician knowledge, attitudes, and behaviors, in the context of substantial variation among sites. PMID:24138608
Effect of initial conditions on constant pressure mixing between two turbulent streams
NASA Astrophysics Data System (ADS)
Kangovi, S.
1983-02-01
It is pointed out that a study of the process of mixing between two dissimilar streams has varied applications in different fields. The applications include the design of an after burner in a high by-pass ratio aircraft engine and the disposal of effluents in a stream. The mixing process determines important quantities related to the energy transfer from main stream to the secondary stream, the temperature and velocity profiles, and the local kinematic and dissipative structure within the mixing region, and the growth of the mixing layer. Hill and Page (1968) have proposed the employment of an 'assumed epsilon' method in which the eddy viscosity model of Goertler (1942) is modified to account for the initial boundary layer. The present investigation is concerned with the application of the assumed epsilon technique to the study of the effect of initial conditions on the development of the turbulent mixing layer between two compressible, nonisoenergetic streams at constant pressure.
Biochemical Study of Mixed Culture Prototype in a Closed Ecological System
NASA Technical Reports Server (NTRS)
Tischer, R. G.
1960-01-01
Since June 1, 1960, the date of initiation of this research project, efforts have been directed toward studying cultural and fermentation patterns and the methodology of pure culture isolation of prototype microorganisms to be employed in closed ecological systems.
Where is the café? The challenge of making retail uses viable in mixed-use suburban developments.
Grant, Jill; Perrott, Katherine
2011-01-01
Contemporary planners see mixing residential, retail and other compatible uses as an essential planning principle. This paper explores the challenges that planners, developers and municipal councillors encounter in trying to implement retail uses as part of the mix in suburban areas in three Canadian cities. The study finds that planners employ evolutionary theories of urban development to naturalise their normative visions of walkable and sociable communities. By contrast, developers point to consumer behaviour to explain why planners' ideas on mix do not work. In a society where people shop at big-box outlets, making the local café or pub commercially viable proves increasingly challenging.
Gao, Song; Rupp, Erik; Bell, Suzanne; Willinger, Martin; Foley, Theresa; Barbaris, Brian; Sáez, A. Eduardo; Arnold, Robert G.; Betterton, Eric
2010-01-01
A new thermocatalytic method to destroy chlorinated solvents has been developed in the laboratory and tested in a pilot field study. The method employs a conventional Pt/Rh catalyst on a ceramic honeycomb. Reactions proceed at moderate temperatures in the simultaneous presence of oxygen and a reductant (mixed redox conditions) to minimize catalyst deactivation. In the laboratory, stable operation with high conversions (above 90% at residence times shorter than 1 s) for perchloroethylene (PCE) is achieved using hydrogen as the reductant. A molar ratio of H2/O2 = 2 yields maximum conversions; the temperature required to produce maximum conversions is sensitive to influent PCE concentration. When a homologous series of aliphatic alkanes is used to replace hydrogen as the reductant, the resultant mixed redox conditions also produce high PCE conversions. It appears that the dissociation energy of the C–H bond in the respective alkane molecule is a strong determinant of the activation energy, and therefore the reaction rate, for PCE conversion. This new method was employed in a pilot field study in Tucson, Arizona. The mixed redox system was operated semicontinuously for 240 days with no degradation of catalyst performance and complete destruction of PCE and trichloroethylene in a soil vapor extraction gas stream. Use of propane as the reductant significantly reduced operating costs. Mixed redox destruction of chlorinated solvents provides a potentially viable alternative to current soil and groundwater remediation technologies. PMID:18991945
Application of zero-inflated poisson mixed models in prognostic factors of hepatitis C.
Akbarzadeh Baghban, Alireza; Pourhoseingholi, Asma; Zayeri, Farid; Jafari, Ali Akbar; Alavian, Seyed Moayed
2013-01-01
In recent years, hepatitis C virus (HCV) infection represents a major public health problem. Evaluation of risk factors is one of the solutions which help protect people from the infection. This study aims to employ zero-inflated Poisson mixed models to evaluate prognostic factors of hepatitis C. The data was collected from a longitudinal study during 2005-2010. First, mixed Poisson regression (PR) model was fitted to the data. Then, a mixed zero-inflated Poisson model was fitted with compound Poisson random effects. For evaluating the performance of the proposed mixed model, standard errors of estimators were compared. The results obtained from mixed PR showed that genotype 3 and treatment protocol were statistically significant. Results of zero-inflated Poisson mixed model showed that age, sex, genotypes 2 and 3, the treatment protocol, and having risk factors had significant effects on viral load of HCV patients. Of these two models, the estimators of zero-inflated Poisson mixed model had the minimum standard errors. The results showed that a mixed zero-inflated Poisson model was the almost best fit. The proposed model can capture serial dependence, additional overdispersion, and excess zeros in the longitudinal count data.
Rapid microfluidic mixing and liquid jets for studying biomolecular chemical dynamics
NASA Astrophysics Data System (ADS)
Langley, Daniel; Abbey, Brian
2018-01-01
X-ray Free-Electron Lasers (XFELs) offer a unique opportunity to study the structural dynamics of proteins on a femtosecond time-scale. To realize the full potential of XFEL sources for studying time-resolved biomolecular processes however, requires the optimization and development of devices that can both act as a trigger and a delivery mechanism for the system of interest. Here we present numerical simulations and actual devices exploring the conditions required for the development of successful mixing and injection devices for tracking the molecular dynamics of proteins in solution on micro to nanosecond timescales using XFELs. The mechanism for combining reagents employs a threefold combination of pico-liter volumes, lamination and serpentine mixing. Focusing and delivering the sample in solution is achieved using the Gas Dynamic Virtual Nozzle (GDVN), which was specifically developed to produce a micrometer diameter, in-vacuum liquid jet. We explore the influence of parameters such as flow rate and gas pressure on the mixing time and jet stability, and explore the formation of rapid homogeneously mixed jets for `mix-and-inject' liquid scattering experiments at Synchrotron and XFEL facilities.
Combined qualitative and quantitative research designs.
Seymour, Jane
2012-12-01
Mixed methods research designs have been recognized as important in addressing complexity and are recommended particularly in the development and evaluation of complex interventions. This article reports a review of studies in palliative care published between 2010 and March 2012 that combine qualitative and quantitative approaches. A synthesis of approaches to mixed methods research taken in 28 examples of published research studies of relevance to palliative and supportive care is provided, using a typology based on a classic categorization put forward in 1992. Mixed-method studies are becoming more frequently employed in palliative care research and resonate with the complexity of the palliative care endeavour. Undertaking mixed methods research requires a sophisticated understanding of the research process and recognition of some of the underlying complexities encountered when working with different traditions and perspectives on issues of: sampling, validity, reliability and rigour, different sources of data and different data collection and analysis techniques.
Coyle, Rachel Margaret; Miltz, Ada Rose; Lampe, Fiona C; Sewell, Janey; Phillips, Andrew N; Speakman, Andrew; Dhar, Jyoti; Sherr, Lorraine; Sadiq, S Tariq; Taylor, Stephen; Ivens, Daniel R; Collins, Simon; Elford, Jonathan; Anderson, Jane; Rodger, Alison
2018-03-08
In the UK, people of black ethnicity experience a disproportionate burden of HIV and STI. We aimed to assess the association of ethnicity with sexual behaviour and sexual health among women and heterosexual men attending genitourinary medicine (GUM) clinics in England. The Attitudes to and Understanding of Risk of Acquisition of HIV is a cross-sectional, self-administered questionnaire study of HIV negative people recruited from 20 GUM clinics in England, 2013-2014. Modified Poisson regression with robust SEs was used to calculate adjusted prevalence ratios (aPR) for the association between ethnicity and various sexual risk behaviours, adjusted for age, study region, education and relationship status. Questionnaires were completed by 1146 individuals, 676 women and 470 heterosexual men. Ethnicity was recorded for 1131 (98.8%) participants: 550 (48.6%) black/mixed African, 168 (14.9%) black/mixed Caribbean, 308 (27.2%) white ethnic groups, 105 (9.3%) other ethnicity. Compared with women from white ethnic groups, black/mixed African women were less likely to report condomless sex with a non-regular partner (aPR (95% CI) 0.67 (0.51 to 0.88)), black/mixed African and black/mixed Caribbean women were less likely to report two or more new partners (0.42 (0.32 to 0.55) and 0.44 (0.29 to 0.65), respectively), and black/mixed Caribbean women were more likely to report an STI diagnosis (1.56 (1.00 to 2.42)). Compared with men from white ethnic groups, black/mixed Caribbean men were more likely to report an STI diagnosis (1.91 (1.20 to 3.04)), but did not report risk behaviours more frequently. Men and women of black/mixed Caribbean ethnicity remained more likely to report STI history after adjustment for sexual risk behaviours. Risk behaviours were reported less frequently by women of black ethnicity; however, history of STI was more prevalent among black/mixed Caribbean women. In black/mixed Caribbean men, higher STI history was not explained by ethnic variation in reported risk behaviours. The association between STI and black/mixed Caribbean ethnicity remained after adjustment for risk behaviours. © 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.
Fully-coupled analysis of jet mixing problems. Three-dimensional PNS model, SCIP3D
NASA Technical Reports Server (NTRS)
Wolf, D. E.; Sinha, N.; Dash, S. M.
1988-01-01
Numerical procedures formulated for the analysis of 3D jet mixing problems, as incorporated in the computer model, SCIP3D, are described. The overall methodology closely parallels that developed in the earlier 2D axisymmetric jet mixing model, SCIPVIS. SCIP3D integrates the 3D parabolized Navier-Stokes (PNS) jet mixing equations, cast in mapped cartesian or cylindrical coordinates, employing the explicit MacCormack Algorithm. A pressure split variant of this algorithm is employed in subsonic regions with a sublayer approximation utilized for treating the streamwise pressure component. SCIP3D contains both the ks and kW turbulence models, and employs a two component mixture approach to treat jet exhausts of arbitrary composition. Specialized grid procedures are used to adjust the grid growth in accordance with the growth of the jet, including a hybrid cartesian/cylindrical grid procedure for rectangular jets which moves the hybrid coordinate origin towards the flow origin as the jet transitions from a rectangular to circular shape. Numerous calculations are presented for rectangular mixing problems, as well as for a variety of basic unit problems exhibiting overall capabilities of SCIP3D.
Investigating the Intersection of Race and Histories in the Classroom
ERIC Educational Resources Information Center
Martell, Christopher C.
2012-01-01
In this practitioner research study, a social studies teacher examined the intersection between his students' race/ethnicity and their experiences learning history. Using the theory of culturally relevant pedagogy as a lens, this study employed mixed methods, analyzing teacher journaling, classroom artifacts, and student reflections, as well as…
Sensitivity enhancements in MQ-MAS NMR of spin-5/2 nuclei using modulated rf mixing pulses
NASA Astrophysics Data System (ADS)
Vosegaard, Thomas; Massiot, Dominique; Grandinetti, Philip J.
2000-08-01
An X- overlineX pulse train with stepped modulation frequency was employed to enhance the multiple-quantum to single-quantum coherence transfer in the mixing period of the multiple-quantum magic-angle spinning (MQ-MAS) experiment for spin I=5/2 nuclei. Two MQ-MAS pulse sequences employing this mixing scheme for the triple-to-single and quintuple-to-single quantum coherence transfers have been designed and their performance is demonstrated for 27Al on samples of NaSi 3AlO 8 and 9Al 2O 3·2B 2O 3 . Compared to the standard single-pulse mixing sequences, the sensitivity is approximately doubled in the present experiments.
How college students conceptualize and practice responsible drinking.
Barry, Adam E; Goodson, Patricia
2011-01-01
This study sought to employ a mixed-methods approach to (a) qualitatively explore responsible drinking beliefs and behaviors among a sample of college students, and (b) quantitatively assess the prevalence of those behaviors. Convenience samples, drawn from currently enrolled students attending a large public university in Texas, comprised 13 participants in the qualitative phase and a random sample of 729 students for the quantitative phase. A partially mixed sequential dominant status design (qual → QUAN) was employed. PARTICIPANTS associated 7 distinct themes with drinking responsibly; however, embedded inside these themes were numerous potentially harmful elements. Quantitative findings supported the qualitative themes, also highlighting gender and ethnic differences. Males believed responsible drinking behaviors should occur with significantly less frequency than females, whereas Whites attached less relative necessity to certain responsible drinking behaviors. This study represents an initial attempt to determine specific, evidence-based characteristics of responsible drinking.
NASA Astrophysics Data System (ADS)
Li, Mingming; Li, Lin; Li, Qiang; Zou, Zongshu
2018-05-01
A filter-based Euler-Lagrange multiphase flow model is used to study the mixing behavior in a combined blowing steelmaking converter. The Euler-based volume of fluid approach is employed to simulate the top blowing, while the Lagrange-based discrete phase model that embeds the local volume change of rising bubbles for the bottom blowing. A filter-based turbulence method based on the local meshing resolution is proposed aiming to improve the modeling of turbulent eddy viscosities. The model validity is verified through comparison with physical experiments in terms of mixing curves and mixing times. The effects of the bottom gas flow rate on bath flow and mixing behavior are investigated and the inherent reasons for the mixing result are clarified in terms of the characteristics of bottom-blowing plumes, the interaction between plumes and top-blowing jets, and the change of bath flow structure.
Passive Microfluidic device for Sub Millisecond Mixing
McMahon, Jay; Mohamed, Hisham; Barnard, David; Shaikh, Tanvir R.; Mannella, Carmen A.; Wagenknecht, Terence; Lu, Toh-Ming
2009-01-01
We report the investigation of a novel microfluidic mixing device to achieve submillisecond mixing. The micromixer combines two fluid streams of several microliters per second into a mixing compartment integrated with two T- type premixers and 4 butterfly-shaped in-channel mixing elements. We have employed three dimensional fluidic simulations to evaluate the mixing efficiency, and have constructed physical devices utilizing conventional microfabrication techniques. The simulation indicated thorough mixing at flow rate as low as 6 µL/s. The corresponding mean residence time is 0.44 ms for 90% of the particles simulated, or 0.49 ms for 95% of the particles simulated, respectively. The mixing efficiency of the physical device was also evaluated using fluorescein dye solutions and FluoSphere-red nanoparticles suspensions. The constructed micromixers achieved thorough mixing at the same flow rate of 6 µL/s, with the mixing indices of 96% ± 1%, and 98% ± 1% for the dye and the nanoparticle, respectively. The experimental results are consistent with the simulation data. The device demonstrated promising capabilities for time resolved studies for macromolecular dynamics of biological macromolecules. PMID:20161619
Orchestrating Mathematical Discourse: Affordances and Hindrances for Novice Elementary Teachers
ERIC Educational Resources Information Center
Lee, Carrie Wilkerson
2016-01-01
The purpose of this study was to examine the mathematical discourse within novice elementary teachers' classrooms. More specifically, this study employed a sequential, explanatory mixed methods design to first quantitatively analyze the relationship between teachers' discourse practices and teacher attributes and school context. Next, a…
Assessing the Potential toward Open Educational Practices in Kyrgyzstan
ERIC Educational Resources Information Center
Walz, Anita R.; Bekbalaeva, Jyldyz
2018-01-01
The study was undertaken to understand the propensity for increased engagement with open educational practices (OEP), to include methods prioritizing student-centered teaching & learning, and awareness, use, and development of open educational resources (OER) among higher education faculty in Kyrgyzstan. The study employed a mixed-methods…
Physical Modelling of the Effect of Slag and Top-Blowing on Mixing in the AOD Process
NASA Astrophysics Data System (ADS)
Haas, Tim; Visuri, Ville-Valtteri; Kärnä, Aki; Isohookana, Erik; Sulasalmi, Petri; Eriç, Rauf Hürman; Pfeifer, Herbert; Fabritius, Timo
The argon-oxygen decarburization (AOD) process is the most common process for refining stainless steel. High blowing rates and the resulting efficient mixing of the steel bath are characteristic of the AOD process. In this work, a 1:9-scale physical model was used to study mixing in a 150 t AOD vessel. Water, air and rapeseed oil were used to represent steel, argon and slag, respectively, while the dynamic similarity with the actual converter was maintained using the modified Froude number and the momentum number. Employing sulfuric acid as a tracer, the mixing times were determined on the basis of pH measurements according to the 97.5% criterion. The gas blowing rate and slag-steel volume ratio were varied in order to study their effect on the mixing time. The effect of top-blowing was also investigated. The results suggest that mixing time decreases as the modified Froude number of the tuyères increases and that the presence of a slag layer increases the mixing time. Furthermore, top-blowing was found to increase the mixing time both with and without the slag layer.
NASA Technical Reports Server (NTRS)
Sherif, S.A.; Hunt, P. L.; Holladay, J. B.; Lear, W. E.; Steadham, J. M.
1998-01-01
Jet pumps are devices capable of pumping fluids to a higher pressure by inducing the motion of a secondary fluid employing a high speed primary fluid. The main components of a jet pump are a primary nozzle, secondary fluid injectors, a mixing chamber, a throat, and a diffuser. The work described in this paper models the flow of a two-phase primary fluid inducing a secondary liquid (saturated or subcooled) injected into the jet pump mixing chamber. The model is capable of accounting for phase transformations due to compression, expansion, and mixing. The model is also capable of incorporating the effects of the temperature and pressure dependency in the analysis. The approach adopted utilizes an isentropic constant pressure mixing in the mixing chamber and at times employs iterative techniques to determine the flow conditions in the different parts of the jet pump.
Study Abroad for Global Engagement: The Long-Term Impact of Mobility Experiences
ERIC Educational Resources Information Center
Paige, R. Michael; Fry, Gerald W.; Stallman, Elizabeth M.; Josic, Jasmina; Jon, Jae-Eun
2009-01-01
This paper reports on the preliminary results of a research project "'Beyond immediate impact: Study abroad for global engagement' (SAGE)" which examines the long-term impact of study abroad on various forms of global engagement. The study employs a retrospective tracer study and mixed methods research design. Survey results from 6391 study-abroad…
The turblent mixing layer - Geometry of large vortices
NASA Astrophysics Data System (ADS)
Browand, F. K.; Troutt, T. R.
1985-09-01
Large spanwide vortices in a mixing layer have been studied in numerous investigations. The present study represents an attempt to define the geometry of the large vortices. In the conducted experiments, the flow develops from a laminar boundary layer, or from an intentionally tripped turbulent boundary layer. However, no other forcing is provided. It is pointed out that in both cases the downstream structure becomes indistinguishable. The experimental apparatus and the employed techniques are discussed, taking into account details regarding the wind tunnel, the detection of the structure, and aspects of digitization. Attention is given to the mean growth of the mixing layer, the mean vortex spacing, the spanwise correlation of vortex structure, velocity-field visualizations, the transition criterion, and the permanence of structure.
Numerical analysis of mixing by sharp-edge-based acoustofluidic micromixer
NASA Astrophysics Data System (ADS)
Nama, Nitesh; Huang, Po-Hsun; Jun Huang, Tony; Costanzo, Francesco
2015-11-01
Recently, acoustically oscillated sharp-edges have been employed to realize rapid and homogeneous mixing at microscales (Huang, Lab on a Chip, 13, 2013). Here, we present a numerical model, qualitatively validated by experimental results, to analyze the acoustic mixing inside a sharp-edge-based micromixer. We extend our previous numerical model (Nama, Lab on a Chip, 14, 2014) to combine the Generalized Lagrangian Mean (GLM) theory with the convection-diffusion equation, while also allowing for the presence of a background flow as observed in a typical sharp-edge-based micromixer. We employ a perturbation approach to divide the flow variables into zeroth-, first- and second-order fields which are successively solved to obtain the Lagrangian mean velocity. The Langrangian mean velocity and the background flow velocity are further employed with the convection-diffusion equation to obtain the concentration profile. We characterize the effects of various operational and geometrical parameters to suggest potential design changes for improving the mixing performance of the sharp-edge-based micromixer. Lastly, we investigate the possibility of generation of a spatio-temporally controllable concentration gradient by placing sharp-edge structures inside the microchannel.
ERIC Educational Resources Information Center
Fidan, Nuray Kurtdede; Ergün, Mustafa
2016-01-01
In this study, social, literary and technological sources used by classroom teachers in social studies courses are analyzed in terms of frequency. The study employs mixed methods research and is designed following the convergent parallel design. In the qualitative part of the study, phenomenological method was used and in the quantitative…
Triggering Transformative Possibilities: A Case Study of Leaders' Quest in China
ERIC Educational Resources Information Center
Lau-Kwong, Kenzie
2012-01-01
This study explored the nature of transformative learning experiences among global executives who participated in Quest program, a learning journey program designed to facilitate shifting mind-sets and worldviews through 1-week intensives in countries such as China. A mixed methods, multiple case study approach was employed. First, a secondary…
Authentic Reading, Writing, and Discussion: An Exploratory Study of a Pen Pal Project
ERIC Educational Resources Information Center
Gambrell, Linda B.; Hughes, Elizabeth M.; Calvert, Leah; Malloy, Jacquelynn A.; Igo, Brent
2011-01-01
In this exploratory study, reading, writing, and discussion were examined within the context of a pen pal intervention focusing on authentic literacy tasks. The study employed a mixed-method design with a triangulation-convergence model to explore the relationship between authentic literacy tasks and the literacy motivation of elementary students…
Chinese Middle School Teachers' Preferences Regarding Performance Evaluation Measures
ERIC Educational Resources Information Center
Liu, Shujie; Xu, Xianxuan; Stronge, James H.
2016-01-01
Teacher performance evaluation currently is receiving unprecedented attention from policy makers, scholars, and practitioners worldwide. This study is one of the few studies of teacher perceptions regarding teacher performance measures that focus on China. We employed a quantitative dominant mixed research design to investigate Chinese teachers'…
ERIC Educational Resources Information Center
Ashworth, Stephanie R.
2013-01-01
The study examined the relationship between secondary public school principals' emotional intelligence and school performance. The correlational study employed an explanatory sequential mixed methods model. The non-probability sample consisted of 105 secondary public school principals in Texas. The emotional intelligence characteristics of the…
Motivating Factors behind Latinas Earning a Baccalaureate Degree
ERIC Educational Resources Information Center
Arizaga Marron, Aryca
2014-01-01
Two concerns served the impetus for this study. Limited literature has created a research gap exploring why Latinas earn baccalaureate degrees from extended universities, and the community central to the study has been lagging behind state and national baccalaureate degree attainment. The researcher employed mixed-methods to describe motivating…
An Avenue for Challenging Sexism: Examining the High School Sociology Classroom
ERIC Educational Resources Information Center
Stevens, Kaylene Mae; Martell, Christopher C.
2016-01-01
In this interpretative qualitative study, the researchers investigated the beliefs and practices of six high school sociology teachers in relation to the teaching of gender. Using a feminist lens, this study employed mixed methods, analyzing teacher interviews, observations, and classroom artifacts. The results showed that the teachers viewed…
Apprehensions and Expectations of the Adoption of Systematically Planned, Outcome-Oriented Practice
ERIC Educational Resources Information Center
Savaya, Riki; Altschuler, Dorit; Melamed, Sharon
2013-01-01
Objectives: The study examined social workers' apprehensions and expectations of the impending adoption of systematically planned, empirically based, outcome-oriented practice (SEOP). Method: Employing a mixed methods longitudinal design, the study used concept mapping to identify and map workers' apprehensions and expectations and a self-reported…
The Indonesian EFL Learners' Motivation in Reading
ERIC Educational Resources Information Center
Salikin, Hairus; Bin-Tahir, Saidna Zulfiqar; Kusumaningputri, Reni; Yuliandari, Dian Puji
2017-01-01
The motivation will drive the EFL learners to be successful in reading. This study examined the Indonesian EFL learners' motivation in reading activity based on Deci and Ryans' theory of motivation including intrinsic and extrinsic. This study employed mixed-method design. The data obtained by distributing questionnaire and arranging the group…
ERIC Educational Resources Information Center
Cash, Jennifer Brown
2013-01-01
Keywords: special education directors, workload, job satisfaction, special education administration. The purpose of this mixed methods research study was to investigate employee characteristics, workload, and job satisfaction of special education directors employed by local education agencies in North Carolina (N = 115). This study illuminates the…
Mixed-Initiative Planning in MAPGEN: Capabilities and Shortcomings
NASA Technical Reports Server (NTRS)
Bresina, John L.; Jonsson, Ari K.; Morris, Paul H.; Rajan, Kanna
2005-01-01
MAPGEN (Mixed-initiative Activity Plan GENerator) is a mixed-initiative system that employs automated constraint-based planning, scheduling, and temporal reasoning to assist the Mars Exploration Rover mission operations staff in generating the daily activity plans. This paper describes the mixed-initiative capabilities of MAPGEN, identifies shortcomings with the deployed system, and discusses ongoing work to address some of these shortcomings.
Numerical Modeling of Mixing and Venting from Explosions in Bunkers
NASA Astrophysics Data System (ADS)
Liu, Benjamin
2005-07-01
2D and 3D numerical simulations were performed to study the dynamic interaction of explosion products in a concrete bunker with ambient air, stored chemical or biological warfare (CBW) agent simulant, and the surrounding walls and structure. The simulations were carried out with GEODYN, a multi-material, Godunov-based Eulerian code, that employs adaptive mesh refinement and runs efficiently on massively parallel computer platforms. Tabular equations of state were used for all materials with the exception of any high explosives employed, which were characterized with conventional JWL models. An appropriate constitutive model was used to describe the concrete. Interfaces between materials were either tracked with a volume-of-fluid method that used high-order reconstruction to specify the interface location and orientation, or a capturing approach was employed with the assumption of local thermal and mechanical equilibrium. A major focus of the study was to estimate the extent of agent heating that could be obtained prior to venting of the bunker and resultant agent dispersal. Parameters investigated included the bunker construction, agent layout, energy density in the bunker and the yield-to-agent mass ratio. Turbulent mixing was found to be the dominant heat transfer mechanism for heating the agent.
Establishment of QC/QA procedures for open-graded mixes : final report.
DOT National Transportation Integrated Search
1998-09-01
The State of Oregon has employed the use of porous concrete surfaces (E- and F-mixes) since the 1970s. The use of porous mixes has increased substantially in the past five years. Previously, no work had been done to evaluate whether the quality contr...
ERIC Educational Resources Information Center
Milne, Harry
2004-01-01
This mixed methods study employed comparative, case-study methodology to explore influences affecting the development of musical interests and achievements in eight female and eight male young adults with Williams Syndrome. Components of the "Schoolwide Enrichment Model"; (Renzulli & Reis, 1997b) were used to guide the study. Caregivers completed…
ERIC Educational Resources Information Center
Custable, Wendy
2013-01-01
This research study examines how Illinois public high school Career and Technical Education educational leaders employ best practices in providing all students rigorous, relevant, and equitable learning experiences within a professional learning community structure. This study utilized a mixed method two-tier case study methodology. Tier one…
Transport and mixing in strongly coupled dusty plasma medium
NASA Astrophysics Data System (ADS)
Dharodi, Vikram; Das, Amita; Patel, Bhavesh
2016-10-01
The generalized hydrodynamic (GHD) fluid model has been employed to study the transport and mixing properties of Dusty plasma medium in strong coupling limit. The response of lighter electron and ion species to the dust motion is taken to be instantaneous i.e. inertia-less. Thus the electron and ion density are presumed to follow the Boltzman relation. In the incompressible limit (i-GHD) the model supports Transverse Shear wave in contrast to the Hydrodynamic fluids. It has been shown that the presence of these waves leads to a better mixing of fluid in this case. Several cases of flow configuration have been considered for the study. The transport and mixing attributes have been quantified by studying the dynamical evolution of tracer particles in the system. The diffusion and clustering of these test particles are directly linked to the mixing characteristic of a medium. The displacement of these particles provides for a quantitative estimate of the diffusion coefficient of the medium. It is shown that these test particles often organize themselves in spatially inhomogeneous pattern leading to the phenomena of clustering.
Paterson, Jessica Louise; Clarkson, Larissa; Rainbird, Sophia; Etherton, Hayley; Blewett, Verna
2015-01-01
Youth are vulnerable to sleep loss and fatigue due to biological, social and psychological factors. However, there are few studies addressing the risk that sleep loss and fatigue pose for youth in the workplace. The aim of this study was to explore work health and safety (WHS) issues for young workers and develop strategies and solutions for improved WHS outcomes, with a focus on issues related to fatigue, using a mixed-method, multi-stage approach. Participants either completed a survey (n=212) or took part in focus groups (n=115) addressing WHS for young workers, or attended a Future Inquiry Workshop (n=29) where strategies for improving youth WHS were developed. Fatigue was identified as a significant problem by the majority of young workers and was associated with unpredictable working time arrangements, precarious employment, high workload, working overtime and limited ability to self-advocate. Participants identified six key areas for action to improve WHS outcomes for young workers; 1) develop expertise, 2) give young workers a voice, 3) improve education and training, 4) build stakeholder engagement, 5) increase employer awareness of WHS responsibilities and, 6) improve processes for employers to manage and monitor WHS outcomes. The application of these directives to fatigue is discussed.
PATERSON, Jessica Louise; CLARKSON, Larissa; RAINBIRD, Sophia; ETHERTON, Hayley; BLEWETT, Verna
2015-01-01
Youth are vulnerable to sleep loss and fatigue due to biological, social and psychological factors. However, there are few studies addressing the risk that sleep loss and fatigue pose for youth in the workplace. The aim of this study was to explore work health and safety (WHS) issues for young workers and develop strategies and solutions for improved WHS outcomes, with a focus on issues related to fatigue, using a mixed-method, multi-stage approach. Participants either completed a survey (n=212) or took part in focus groups (n=115) addressing WHS for young workers, or attended a Future Inquiry Workshop (n=29) where strategies for improving youth WHS were developed. Fatigue was identified as a significant problem by the majority of young workers and was associated with unpredictable working time arrangements, precarious employment, high workload, working overtime and limited ability to self-advocate. Participants identified six key areas for action to improve WHS outcomes for young workers; 1) develop expertise, 2) give young workers a voice, 3) improve education and training, 4) build stakeholder engagement, 5) increase employer awareness of WHS responsibilities and, 6) improve processes for employers to manage and monitor WHS outcomes. The application of these directives to fatigue is discussed. PMID:25752253
Kim, Han S; Weber, Walter J
2005-04-01
The effects of mechanical mixing on rates of polycyclic aromatic hydrocarbon (PAH) biodegradation in dense geosorbent slurry (67% solids content, w/w) systems were evaluated using laboratory-scale intermittently mixed batch bioreactors. A PAH-contaminated soil and a phenanthrene-sorbed mineral sorbent (alpha-Al2O3) were respectively employed as slurry solids in aerobic and anaerobic biodegradation studies. Both slurries exhibited a characteristic behavior of pseudoplastic non-Newtonian fluids, and the impeller revolution rate and its diameter had dramatic impacts on power and torque requirements in their laminar flow mixing. Rates of phenanthrene biodegradation were markedly enhanced by relatively low-level auger mixing under both aerobic and anaerobic (denitrifying) conditions. Parameters for empirical models correlating biodegradation rate coefficient (k(b)) values to the degree of mixing were similar to those for correlations between mass transfer (desorption) rate coefficient (k(r)) values for rapidly desorbing fractions of soil organic matter and degree of mixing reported in a companion study, supporting a conclusion that performance-efficient and cost-effective enhancements of PAH mass transfer (desorption) and its biodegradation processes can be achieved by the introduction of optimal levels of reactor-scale mechanical mixing.
Trainee Teachers' Experience of Reflection
ERIC Educational Resources Information Center
McKenzie, Liz
2015-01-01
This article reports an investigation of trainee teachers' experience of reflection whilst undertaking a teaching qualification for the post-compulsory sector. The study used a sequential, mixed-methods design, employing a structured questionnaire and a semi-structured interview; 127 individuals completed the questionnaire about their experience…
Simulation of mixing in the quick quench region of a rich burn-quick quench mix-lean burn combustor
NASA Technical Reports Server (NTRS)
Shih, Tom I.-P.; Nguyen, H. Lee; Howe, Gregory W.; Li, Z.
1991-01-01
A computer program was developed to study the mixing process in the quick quench region of a rich burn-quick quench mix-lean burn combustor. The computer program developed was based on the density-weighted, ensemble-averaged conservation equations of mass, momentum (full compressible Navier-Stokes), total energy, and species, closed by a k-epsilon turbulence model with wall functions. The combustion process was modeled by a two-step global reaction mechanism, and NO(x) formation was modeled by the Zeldovich mechanism. The formulation employed in the computer program and the essence of the numerical method of solution are described. Some results obtained for nonreacting and reacting flows with different main-flow to dilution-jet momentum flux ratios are also presented.
Gioia, Deborah; Brekke, John S
2003-01-01
Employment is an important outcome for individuals with schizophrenia and the Americans with Disabilities Act (ADA) is a key structural variable designed to favorably influence work. Little is known about how individuals understand and utilize ADA rights. The purpose of this mixed method study was to elicit understanding of the knowledge and use of ADA provisions from 20 persons with schizophrenia who returned to work. Three distinct groups emerged. Group differences suggest that use of ADA provisions may be dependent on individual need and comfort with ADA opportunity.
Cardarelli, Roberto; Reese, David; Roper, Karen L.; Cardarelli, Kathryn; Feltner, Frances J.; Studts, Jamie L.; Knight, Jennifer R.; Armstrong, Debra; Weaver, Anthony; Shaffer, Dana
2017-01-01
For low dose CT lung cancer screening to be effective in curbing disease mortality, efforts are needed to overcome barriers to awareness and facilitate uptake of the current evidence-based screening guidelines. A sequential mixed-methods approach was employed to design a screening campaign utilizing messages developed from community focus groups, followed by implementation of the outreach campaign intervention in two high-risk Kentucky regions. This study reports on rates of awareness and screening in intervention regions, as compared to a control region. PMID:27866066
Race, Employment Disadvantages, and Heavy Drinking: A Multilevel Model.
Lo, Celia C; Cheng, Tyrone C
2015-01-01
We intended to determine (1) whether stress from employment disadvantages led to increased frequency of heavy drinking and (2) whether race had a role in the relationship between such disadvantages and heavy drinking. Study data came from the National Longitudinal Survey of Youth, a prospective study that has followed a representative sample of youth since 1979. Our study employed data from 11 particular years, during which the survey included items measuring respondents' heavy drinking. Our final sample numbered 10,171 respondents, which generated 75,394 person-waves for data analysis. Both of our hypotheses were supported by results from multilevel mixed-effects linear regression capturing the time-varying nature of three employment disadvantages and of the heavy-drinking outcome. Results show that more-frequent heavy drinking was associated with employment disadvantages, and that disadvantages' effects on drinking were stronger for Blacks and Hispanics than for Whites. That worsening employment disadvantages have worse effects on minority groups' heavy drinking (compared to Whites) probably contributes to the racial health disparities in our nation. Policies and programs addressing such disparities are especially important during economic downturns.
Study of Active Micromixer Driven by Electrothermal Force
NASA Astrophysics Data System (ADS)
Huang, Kuan-Rong; Chang, Jeng-Shian; Chao, Sheng D.; Wung, Tzong-Shyan; Wu, Kuang-Chong
2012-04-01
Biochemical applications of microchips often require a rapid mixing of different fluid samples. At the microscale level, fluid flow is usually a highly ordered laminar flow and diffusion is the primary mechanism for mixing owing to the lack of disturbances, yielding inefficiency for practical biochemical analysis. In this work, we design a prototype active micromixer by employing the electrothermal effect. We apply to the flow microchannel a non-uniform AC electric field, which can generate an electrothermal force on the fluid flow and induce vortex pairs for enhancing mixing efficiency. The performance of this active micromixer is studied and compared, under the same mixing quality, with that of a conventional passive micromixer of the same size with obstacles in the flow channel by three-dimensional finite element simulations. The numerical results show that the pressure drop between the inlet and the outlet for the active micromixer is much less than (only 3000th) that for the passive micro-mixer with the same mixing quality. To obtain an optimal mixing quality, we have systematically studied the mixing quality by varying the geometrical arrangements of the electrodes. An almost complete mixing can be obtained using a specific design. Moreover, the temperature increases around the electrodes are lower than 3 K, which does not adversely affect the biochemical analysis. It is suggested that the prototype active micromixer designed is promising and effective and useful for biochemical analysis.
ERIC Educational Resources Information Center
Rowell, Lonnie L.; Polush, Elena Yu; Riel, Margaret; Bruewer, Aaron
2015-01-01
The purpose of this study was to identify distinguishing characteristics of action research within the Action Research Special Interest Group of the American Educational Research Association. The authors sought to delineate the foundational framework endorsed by this community. The study was conducted during January-April 2012 and employed an…
Adult Learners' Use of Flexible Online Resources in a Blended Programme
ERIC Educational Resources Information Center
Cornelius, Sarah; Gordon, Carole
2009-01-01
This paper presents a case study of a blended programme for adults and discusses findings from a mixed-methods investigative study of learners' and tutors' experiences of the programme. The programme employs a set of flexible online resources, which are activity-based and designed to provide choice in study routes and modes of learning. Our…
The Effects of CMC Applications on ESL Writing Anxiety among Postgraduate Students
ERIC Educational Resources Information Center
Hussin, Supyan; Abdullah, Mohamad Yahya; Ismail, Noriah; Yoke, Soo Kum
2015-01-01
This study investigates the effects of the CMC applications on the ESL/EFL writing anxiety. This is a descriptive study using a mixed-method that adopted both quantitative and qualitative approaches. Three instruments were employed to answer the research questions of the current study which are Second Language Writing Anxiety Inventory (SLWAI),…
A Proposed Model of Retransformed Qualitative Data within a Mixed Methods Research Design
ERIC Educational Resources Information Center
Palladino, John M.
2009-01-01
Most models of mixed methods research design provide equal emphasis of qualitative and quantitative data analyses and interpretation. Other models stress one method more than the other. The present article is a discourse about the investigator's decision to employ a mixed method design to examine special education teachers' advocacy and…
A Case Study of Computer Gaming for Math: Engaged Learning from Gameplay?
ERIC Educational Resources Information Center
Ke, Fengfeng
2008-01-01
Employing mixed-method approach, this case study examined the in situ use of educational computer games in a summer math program to facilitate 4th and 5th graders' cognitive math achievement, metacognitive awareness, and positive attitudes toward math learning. The results indicated that students developed more positive attitudes toward math…
Race and Histories: Examining Culturally Relevant Teaching in the U.S. History Classroom
ERIC Educational Resources Information Center
Martell, Christopher C.
2013-01-01
In this practitioner research study, the author, a White social studies teacher, examined the intersection between his students' race/ethnicity and their experiences learning history. Using critical race theory as a lens, the author employed mixed methods, analyzing teacher journaling, classroom artifacts, and student reflections, as well as…
Native Chinese-Speaking K-12 Language Teachers' Beliefs and Practices
ERIC Educational Resources Information Center
Lü, Chan; Lavadenz, Magaly
2014-01-01
This study investigated the relationships between the beliefs and practices of K-12 native Chinese teachers on Chinese language and literacy instruction. Using a descriptive-exploratory design, this study employed a mixed-methods approach consisting of three steps: (1) a teacher beliefs questionnaire, (2) classroom observations and videotaping,…
The Effect of Situated Learning on Students Vocational English Learning
ERIC Educational Resources Information Center
Özüdogru, Melike; Özüdogru, Fatma
2017-01-01
The current study aimed to find out the effect of situated learning on students' Vocational English learning. This research employed a mixed method research design. In the quantitative part of the study, pre-tests and post-tests were implemented to investigate the differences in students' vocational English learning between the experimental and…
Preschool Teachers' Perceived Math Anxiety and Self-Efficacy for Teaching Mathematics
ERIC Educational Resources Information Center
Cook, Carolyn D.
2017-01-01
This study explored the relationship between math anxiety and perceived self-efficacy for teaching mathematics in preschool teachers. Perceptions of and attributions for the teachers' perceived math anxiety and perceived self-efficacy for teaching mathematics were also explored. The study employed a mixed-method design consisting of both…
ERIC Educational Resources Information Center
Ke, Fengfeng
2008-01-01
This article reports findings on a study of educational computer games used within various classroom situations. Employing an across-stage, mixed method model, the study examined whether educational computer games, in comparison to traditional paper-and-pencil drills, would be more effective in facilitating comprehensive math learning outcomes,…
ERIC Educational Resources Information Center
Taylor, Deborah L.
2013-01-01
This study explored the perspectives of faculty at six evangelical Christian universities concerning cultural diversity and how theological beliefs might impact faculty members' commitment to a culturally competent pedagogy. A mixed methods design employing both quantitative (survey) and qualitative (interviews) was utilized for data collection.…
ERIC Educational Resources Information Center
Prioleau, Lushandra
2013-01-01
This study examined the effective strategies, resources, and programs urban superintendents utilize to improve the academic achievement for African-American males. This study employed a mixed-methods approach to answer the following research questions regarding urban superintendents and the academic achievement for African-American males: What…
ERIC Educational Resources Information Center
Berrin, Sebastian Everett
2010-01-01
This study used a mixed-method approach to examine students' experiences in multicultural training and their opinions about various aspects of their course(s). A developmental model of learning was employed to analyze results. More specifically, this study explored the relationship between clinical psychology doctoral students' self-reported…
Issues of Perception Post 9/11 and Implications for Antiterrorism Education
ERIC Educational Resources Information Center
Barner, Rayford E.
2015-01-01
This research study sought to determine a connection between antiterrorism education training and police officer's perception of the cultural communities implicated in the September 11, 2001 terrorist attacks. The study employs a mixed-methods research design using surveys and interviews. The sample is taken from 52 police officers of a police…
ERIC Educational Resources Information Center
Tillman, Beverly A.; Richards, Stephen B.; Frank, Catherine Lawless
2011-01-01
This study employed a Likert-type survey, "Praxis/Pathwise" written observations, as well as guided and open-ended reflections to assess the perceptions of preparedness for the first year of teaching for special education student teaching candidates. Cooperating teachers completed the survey and "Praxis/Pathwise" observations.…
A Learning Environment for English Vocabulary Using Quick Response Codes
ERIC Educational Resources Information Center
Arikan, Yuksel Deniz; Ozen, Sevil Orhan
2015-01-01
This study focuses on the process of developing a learning environment that uses tablets and Quick Response (QR) codes to enhance participants' English language vocabulary knowledge. The author employed the concurrent triangulation strategy, a mixed research design. The study was conducted at a private school in Izmir, Turkey during the 2012-2013…
Positive versus Negative Communication Strategies in Task-Based Learning
ERIC Educational Resources Information Center
Rohani, Siti
2013-01-01
This study aimed at describing how the implementation of Task-Based Learning (TBL) would shape or change students' use of oral communication strategies. Students' problems and strategies to solve the problems during the implementation of TBL were also explored. The study was a mixed method, employing both quantitative and qualitative analysis…
Reading Habits of College Students in the United States
ERIC Educational Resources Information Center
Huang, SuHua; Capps, Matthew; Blacklock, Jeff; Garza, Mary
2014-01-01
This study employed a convergent mixed-method research design to investigate reading habits of American college students. A total of 1,265 (466 male and 799 female) college students voluntarily participated in the study by completing a self-reported survey. Twelve students participated in semi-structured interviews and classroom observations.…
Evaluation of an Online Study Skills Course
ERIC Educational Resources Information Center
Pryjmachuk, Steven; Gill, Anita; Wood, Patricia; Olleveant, Nicola; Keeley, Philip
2012-01-01
This article describes the evaluation of an online study skills course unit designed, using evidence-based principles, to support undergraduate students. A mixed-methods approach was employed to establish the extent to which the unit was (a) fit for purpose and (b) effective. Data were obtained from an online survey (n = 63) conducted on entry to…
Lorenz, Jana
2018-01-01
Background Goal setting is among the most common behavioral change techniques employed in contemporary self-tracking apps. For these techniques to be effective, it is relevant to understand how the visual presentation of goal-related outcomes employed in the app design affects users’ responses to their self-tracking outcomes. Objective This study examined whether a spatially close (vs distant) presentation of mixed positive and negative self-tracking outcomes from multiple domains (ie, activity, diet) on a digital device’s screen can provide users the opportunity to hedonically edit their self-tracking outcome profile (ie, to view their mixed self-tracking outcomes in the most positive light). Further, this study examined how the opportunity to hedonically edit one’s self-tracking outcome profile relates to users’ future health behavior intentions. Methods To assess users’ responses to a spatially close (vs distant) presentation of a mixed-gain (vs mixed-loss) self-tracking outcome profile, a randomized 2×2 between-subjects online experiment with a final sample of 397 participants (mean age 27.4, SD 7.2 years; 71.5%, 284/397 female) was conducted in Germany. The experiment started with a cover story about a fictitious self-tracking app. Thereafter, participants saw one of four manipulated self-tracking outcome profiles. Variables of interest measured were health behavior intentions, compensatory health beliefs, health motivation, and recall of the outcome profile. We analyzed data using chi-square tests (SPSS version 23) and moderated mediation analyses with the PROCESS macro 2.16.1. Results Spatial distance facilitated hedonic editing, which was indicated by systematic memory biases in users’ recall of positive and negative self-tracking outcomes. In the case of a mixed-gain outcome profile, a spatially close (vs distant) presentation tended to increase the underestimation of the negative outcome (P=.06). In the case of a mixed-loss outcome profile, a spatially distant (vs close) presentation facilitated the exact recognition of the positive outcome (P=.04). When the presentation of self-tracking outcomes provided the opportunity for hedonic editing, users with a low (vs high) health motivation produced compensatory health beliefs, which led to lower health behavior intentions (index of moderated mediation=0.0352, 95% CI 0.0011-0.0923). Conclusions When spatial distance between the presentations of mixed self-tracking outcomes provided the opportunity to hedonically edit one’s self-tracking outcome profile, users recalled their self-tracking outcomes in a more positive light. Especially for users with lower health motivation, the opportunity to hedonically edit one’s mixed self-tracking outcome profile led to reduced health behavior intentions. To prevent the occurrence of hedonic editing in users’ responses to visually presented self-tracking outcome profiles, further research is necessary to determine the ideal distance that should be employed in the app design for the presentation of mixed self-tracking outcomes on a digital device’s screen. PMID:29643051
A Product Development Decision Model for Cockpit Weather Information System
NASA Technical Reports Server (NTRS)
Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin; Johnson, Edward J., Jr. (Technical Monitor)
2003-01-01
There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.
A Product Development Decision Model for Cockpit Weather Information Systems
NASA Technical Reports Server (NTRS)
Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin
2003-01-01
There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.
78 FR 35038 - Proposed Information Collection Activity; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-11
..., reliable, and transparent method for identifying high-quality programs that can receive continuing five... the system is working. The study will employ a mixed-methods design that integrates and layers administrative and secondary data sources, observational measures, and interviews to develop a rich knowledge...
Broadcast Journalism Education and the Capstone Experience
ERIC Educational Resources Information Center
Tanner, Andrea; Forde, Kathy Roberts; Besley, John C.; Weir, Tom
2012-01-01
This study assesses the current state of the television news capstone experience in accredited journalism and mass communication programs in the United States. Specifically, the authors employed a mixed-methods approach, interviewing 20 television news capstone instructors and conducting an analysis of broadcast journalism curriculum information…
The employment environment for youth in rural South Africa: A mixed-methods study
Wilkinson, Andra; Pettifor, Audrey; Rosenberg, Molly; Halpern, Carolyn; Thirumurthy, Harsha; Collinson, Mark A.; Kahn, Kathleen
2016-01-01
South Africa has high youth unemployment. This paper examines the predictors of youth employment in rural Agincourt, Mpumalanga Province. A survey of 187 out-of-school 18–24 year olds found only 12% of women and 38% of men were currently employed. Men with skills/training were significantly more likely to report employment, mostly physical labour (aOR: 4.5; CI: 1.3, 15.3). In-depth interviews with 14 of the youth revealed women are perceived more suitable for formal employment, which is scarce informing why women were more likely to pursue further education and yet less likely to be employed. Ten key informants from local organisations highlighted numerous local youth employment resources while, in contrast, all youth in the sample said no resources were available, highlighting a need for the organisations to extend their services into rural areas. As these services are focused on entrepreneurship, programs to increase financial literacy and formal employment opportunities are also needed. PMID:28190915
The employment environment for youth in rural South Africa: A mixed-methods study.
Wilkinson, Andra; Pettifor, Audrey; Rosenberg, Molly; Halpern, Carolyn; Thirumurthy, Harsha; Collinson, Mark A; Kahn, Kathleen
2017-01-01
South Africa has high youth unemployment. This paper examines the predictors of youth employment in rural Agincourt, Mpumalanga Province. A survey of 187 out-of-school 18-24 year olds found only 12% of women and 38% of men were currently employed. Men with skills/training were significantly more likely to report employment, mostly physical labour (aOR: 4.5; CI: 1.3, 15.3). In-depth interviews with 14 of the youth revealed women are perceived more suitable for formal employment, which is scarce informing why women were more likely to pursue further education and yet less likely to be employed. Ten key informants from local organisations highlighted numerous local youth employment resources while, in contrast, all youth in the sample said no resources were available, highlighting a need for the organisations to extend their services into rural areas. As these services are focused on entrepreneurship, programs to increase financial literacy and formal employment opportunities are also needed.
Consumer-directed health plans: mixed employer signals, complex market dynamics.
Tynan, Ann; Christianson, Jon B
2008-03-01
Health plans have expanded consumer-directed health plan (CDHP) product offerings--typically high-deductible health plans coupled with a spending account--and more employers are offering these products to workers, according to findings from the Center for Studying Health System Change's (HSC) 2007 site visits to 12 nationally representative metropolitan communities. In developing CDHPs, health plans are responding to a broader employer strategy to confer more responsibility on workers for their health care costs, lifestyle choices and treatment decisions. CDHP adoption by employers and consumers depends on a range of factors, including product features and employer characteristics, and varies across the 12 communities. While more large employers are introducing CDHPs into health benefit programs, adoption of CDHPs remains modest. Health plans and employers expect CDHP enrollment to grow as employers and employees become more knowledgeable about CDHP features, health plans develop more sophisticated support tools for plan enrollees, and there are more opportunities to learn from early adopters' experiences.early
A 547 GHz SIS Receiver Employing a Submicron Nb Junction with an Integrated Matching Circuit
NASA Technical Reports Server (NTRS)
Febvre, P.; McGrath, W.; Leduc, H.; Batelaan, P.; Frerking, M.; Hernichel, J.; Bumble, B.
1993-01-01
The most sensitive heterodyne receivers used for millimeter wave and submillimeter wave radioastronomy employ superconductor-insulator-superconductor (SIS) tunnel junctions as the nonlinear mixing element.
Stakeholders' Views of South Korea's Higher Education Internationalization Policy
ERIC Educational Resources Information Center
Cho, Young Ha; Palmer, John D.
2013-01-01
The study investigated the stakeholders' perceptions of South Korea's higher education internationalization policy. Based on the research framework that defines four policy values--propriety, effectiveness, diversity, and engagement, the convergence model was employed with a concurrent mixed method sampling strategy to analyze the stakeholders'…
Development of Pre-Service Chemistry Teachers' Technological Pedagogical Content Knowledge
ERIC Educational Resources Information Center
Cetin-Dindar, Ayla; Boz, Yezdan; Sonmez, Demet Yildiran; Celep, Nilgun Demirci
2018-01-01
In this study, a mixed-method design was employed to investigate pre-service chemistry teachers' Technological Pedagogical Content Knowledge (TPACK) development. For effective technology integration in instruction, knowledge about technology is not enough; teachers should have different knowledge types which are content, pedagogical, and…
ERIC Educational Resources Information Center
Kuo, Yu-Chun; Belland, Brian R.; Kuo, Yu-Tung
2017-01-01
This study employed a mixed method approach to investigate the relationships between learners' blogging self-efficacy, sense of community, perceived collaborative learning, and perceived learning in classroom environments. Learners' perspectives of group learning experiences in blog-enhanced settings were examined. Participants were minority adult…
Teacher Candidate Technology Integration: For Student Learning or Instruction?
ERIC Educational Resources Information Center
Clark, Cynthia; Zhang, Shaoan; Strudler, Neal
2015-01-01
Transfer of instructional technology knowledge for student-centered learning by teacher candidates is investigated in this study. Using the transfer of learning theoretical framework, a mixed methods research design was employed to investigate whether secondary teacher candidates were able to transfer the instructional technology knowledge for…
Study of the flow mixing in a novel ARID raceway for algae production
Xu, Ben; Li, Peiwen; Waller, P.
2014-07-31
A novel flow field for algae raceways has been proposed, which is fundamentally different from traditional paddlewheel-driven raceways. To reduce freezing and heat loss in the raceway during cold time, the water is drained to a deep storage canal. The ground bed of the new raceway has a low slope so that water, lifted by propeller pump, can flow down in laterally-laid serpentine channels, relying on gravitational force. The flow rate of water is controlled so that it can overflow the lateral channel walls and mix with the main flow in the next lower channel, which thus creates a bettermore » mixing. In order to optimize the design parameters of the new flow field, methods including flow visualization, local point velocity measurement, and CFD analysis were employed to investigate the flow mixing features. Different combinations of channel geometries and water velocities were evaluated. An optimized flow field design and details of flow mixing are presented. The study offers an innovative design for large scale algae growth raceways which is of significance to the algae and biofuel industry.« less
Study of the flow mixing in a novel ARID raceway for algae production
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Ben; Li, Peiwen; Waller, P.
A novel flow field for algae raceways has been proposed, which is fundamentally different from traditional paddlewheel-driven raceways. To reduce freezing and heat loss in the raceway during cold time, the water is drained to a deep storage canal. The ground bed of the new raceway has a low slope so that water, lifted by propeller pump, can flow down in laterally-laid serpentine channels, relying on gravitational force. The flow rate of water is controlled so that it can overflow the lateral channel walls and mix with the main flow in the next lower channel, which thus creates a bettermore » mixing. In order to optimize the design parameters of the new flow field, methods including flow visualization, local point velocity measurement, and CFD analysis were employed to investigate the flow mixing features. Different combinations of channel geometries and water velocities were evaluated. An optimized flow field design and details of flow mixing are presented. The study offers an innovative design for large scale algae growth raceways which is of significance to the algae and biofuel industry.« less
Microfluidic T-form mixer utilizing switching electroosmotic flow.
Lin, Che-Hsin; Fu, Lung-Ming; Chien, Yu-Sheng
2004-09-15
This paper presents a microfluidic T-form mixer utilizing alternatively switching electroosmotic flow. The microfluidic device is fabricated on low-cost glass slides using a simple and reliable fabrication process. A switching DC field is used to generate an electroosmotic force which simultaneously drives and mixes the fluid samples. The proposed design eliminates the requirements for moving parts within the microfluidic device and delicate external control systems. Two operation modes, namely, a conventional switching mode and a novel pinched switching mode, are presented. Computer simulation is employed to predict the mixing performance attainable in both operation modes. The simulation results are then compared to those obtained experimentally. It is shown that a mixing performance as high as 97% can be achieved within a mixing distance of 1 mm downstream from the T-junction when a 60 V/cm driving voltage and a 2-Hz switching frequency are applied in the pinched switching operation mode. This study demonstrates how the driving voltage and switching frequency can be optimized to yield an enhanced mixing performance. The novel methods presented in this study provide a simple solution to mixing problems in the micro-total-analysis-systems field.
ERIC Educational Resources Information Center
Martell, Christopher C.
2014-01-01
In this interpretative case study, the researcher examined the beliefs and practices of three social studies teachers related to their teaching of race in U.S. history at a racially and ethnically diverse urban high school. Using the theory of culturally relevant pedagogy as a lens, this study employed mixed methods, analyzing teacher interviews,…
ERIC Educational Resources Information Center
Townsend, Tony; Pisapia, John; Razzaq, Jamila
2015-01-01
The aim of this paper is to describe actions designed to foster interdisciplinary research efforts at a major university in the UK. The study employed a descriptive mixed method case study approach to collecting and analysing the data used to draw its conclusions. One hundred and twenty-seven academic staff responded to the survey. The results of…
ERIC Educational Resources Information Center
Kaskaya, Alper; Unlu, Ihsan; Akar, M. Said; Ozturan Sagirli, Meryem
2011-01-01
The aim of this study is to investigate the effects of school and teacher themed movies on pre-service teachers' attitudes towards their profession and their perceived self-efficacy. As qualitative and quantitative research approaches were employed during data collection procedure, mixed methodology was adopted in this study. In the study, one of…
ERIC Educational Resources Information Center
Martell, Christopher C.
2013-01-01
In this study, the researcher examined student conceptions of "Whiteness" as it relates to past and present U.S. history. Using Critical Race Theory as the lens, this study employed mixed methods, analyzing teacher observations, classroom artifacts/student work, survey, and interview data from White students and students of color at an…
On the Use of a Mixed Gaussian/Finite-Element Basis Set for the Calculation of Rydberg States
NASA Technical Reports Server (NTRS)
Thuemmel, Helmar T.; Langhoff, Stephen (Technical Monitor)
1996-01-01
Configuration-interaction studies are reported for the Rydberg states of the helium atom using mixed Gaussian/finite-element (GTO/FE) one particle basis sets. Standard Gaussian valence basis sets are employed, like those, used extensively in quantum chemistry calculations. It is shown that the term values for high-lying Rydberg states of the helium atom can be obtained accurately (within 1 cm -1), even for a small GTO set, by augmenting the n-particle space with configurations, where orthonormalized interpolation polynomials are singly occupied.
Study of vibrational modes in CuxAg1-xIn5S8 mixed crystals by infrared reflection measurements
NASA Astrophysics Data System (ADS)
Gasanly, N. M.
2018-04-01
Infrared reflection spectra of CuxAg1-xIn5S8 mixed crystals, grown by Bridgman method, were studied in the wide frequency range of 50-2000 cm-1. All four infrared-active modes were detected, which are in full agreement with the prediction of group-theoretical analysis. Real and imaginary parts of the dielectric function, refractive index and the energy losses function were evaluated from reflectivity measurements. The frequencies of TO and LO modes and oscillator strengths were also determined. The bands detected in IR spectra of studied crystals were assigned to various vibration types (valence and valence-deformation) on the basis of the symmetrized displacements of atoms obtained employing the Melvin projection operators. The linear dependencies of optical mode frequencies on the composition of CuxAg1-xIn5S8 mixed crystals were obtained. These dependencies display one-mode behavior.
Institutional Gender Equity Salary Analysis and Recursive Impact of Career and Life Choices
ERIC Educational Resources Information Center
Peterson, Teri S.
2013-01-01
This study employed mixed methods, engaging both quantitative and qualitative inquiries. In terms of the quantitative inquiry, the purpose of this study was to explore and assess gender-based salary inequities at a Carnegie Classified Research High university in the Intermountain West. Qualitative inquiry was used to follow up and contextually…
ERIC Educational Resources Information Center
Tai, Joanna Hong-Meng; Canny, Benedict J.; Haines, Terry P.; Molloy, Elizabeth K.
2016-01-01
This study explored the contribution of peer-assisted learning (PAL) in the development of evaluative judgement capacity; the ability to understand work quality and apply those standards to appraising performance. The study employed a mixed methods approach, collecting self-reported survey data, observations of, and reflective interviews with, the…
The Effect of Portfolio Assessments on Metacognitive Skills and on Attitudes toward a Course
ERIC Educational Resources Information Center
Gencel, Ilke Evin
2017-01-01
The aim of this study is to determine through teacher candidates' thoughts the effects of a portfolio assessment implementation on their metacognitive skills and attitudes towards a course on measurement and evaluation. Exploratory sequential mixed-methods design is employed within the study. The pretest/posttest control group design was used in…
Developing Appropriate Workforce Skills for Australia's Emerging Digital Economy: Working Paper
ERIC Educational Resources Information Center
Gekara, Victor; Molla, Alemayehu; Snell, Darryn; Karanasios, Stan; Thomas, Amanda
2017-01-01
This working paper is the first publication coming out of a project investigating the role of vocational education and training (VET) in developing digital skills in the Australian workforce, using two sectors as case studies--Transport and Logistics, and Public Safety and Correctional Services. The study employs a mixed method approach, combining…
The Effect of a State Department of Education Teacher Mentor Initiative on Science Achievement
ERIC Educational Resources Information Center
Pruitt, Stephen L.
2010-01-01
This study analyzed a state department of education's ability to have actual influence over the improvement of science achievement and proficiency by having direct relationships with science teachers in Georgia's lowest performing schools. The study employed a mixed ANOVA analysis of the mean scale scores and proficiency rates of the science…
Integrating Technology into Instruction at a Public University in Kyrgyzstan: Barriers and Enablers
ERIC Educational Resources Information Center
Muhametjanova, Gulshat; Cagiltay, Kursat
2016-01-01
The purpose of this study was to determine enablers and barriers to the technology integration into education based on the example of the situation at the Kyrgyz-Turkish Manas University as reported by students and instructors. The study employed the mixed-methods research design, combining data obtained from 477 student and 57 instructor…
Exploring Advertising in Higher Education: An Empirical Analysis in North America, Europe, and Japan
ERIC Educational Resources Information Center
Papadimitriou, Antigoni; Blanco Ramírez, Gerardo
2015-01-01
This empirical study explores higher education advertising campaigns displayed in five world cities: Boston, New York, Oslo, Tokyo, and Toronto. The study follows a mixed-methods research design relying on content analysis and multimodal semiotic analysis and employs a conceptual framework based on the knowledge triangle of education, research,…
ICT Accessibility and Usability to Support Learning of Visually-Impaired Students in Tanzania
ERIC Educational Resources Information Center
Eligi, Innosencia; Mwantimwa, Kelefa
2017-01-01
The main objective of this study was to assess the accessibility and usability of Information and Communication Technology facilities to facilitate learning among visually-impaired students at the University of Dar es Salaam (UDSM). The study employed a mixed methods design in gathering, processing and analysing quantitative and qualitative data.…
ERIC Educational Resources Information Center
Ojose, Bobby
2015-01-01
This study investigated proportional reasoning and the related concepts of decimal, percent, and ratio. In particular, the research focused on analyzing the gaps and understandings that grades 6, 7, and 8 students have and advanced factors for such gaps and understandings. The study employed a mixed method approach in which quantitative data was…
Exploring Arts Instruction Models and Correlates with Teacher Satisfaction and Educational Outcomes
ERIC Educational Resources Information Center
Randall, Kristen Leigh
2012-01-01
The purpose of this study was to explore uses of arts instruction in regular K-5 elementary school classrooms in a large southeastern school district to determine which arts instruction models were being employed and whether or not any particular model had a greater perceived impact on students and teachers. The mixed-methods study combined…
Planning a Teaching Sequence for the Teaching of Chemical Bonding
ERIC Educational Resources Information Center
Sibanda, Doras; Hobden, Paul
2015-01-01
The current study seeks to examine how teachers plan teaching sequences to teach chemical bonding in the senior secondary phase of schooling. The study employs a learning demand tool as interpretive framework. A mixed method was used to guide the collection of data. Data were collected through a survey instrument with 227 practising physical…
Preconditions for Post-Employment Learning: Preliminary Results from Ongoing Research
ERIC Educational Resources Information Center
Salter, Linda
2011-01-01
This article describes the first phase of a two-phase, mixed-method study. The study, now in progress, explores how and to what extent willingness to engage in learning in mature adulthood is influenced by prior experiences and specific individual personality variables, such as perceived locus of control and degree of self-efficacy. Study…
Faculty Perceptions of, and Experiences with, African American Male Students at a Community College
ERIC Educational Resources Information Center
Jenkins, Shantelle K.
2013-01-01
Many studies involving African American male students have focused on achievement gaps and student retention models of those attending four-year institutions. However, there are limited investigations of African American male students at the community college and very few that focus on faculty perceptions. This study employed a mixed Delphi…
Importance and Effectiveness of Student Health Services at a South Texas University
ERIC Educational Resources Information Center
McCaig, Marilyn M.
2013-01-01
The study examined the health needs of students at a south Texas university and documented the utility of the student health center. The descriptive study employed a mixed methods explanatory sequential design (ESD). The non-probability sample consisted of 140 students who utilized the university's health center during the period of March 23-30,…
Work Participation and Academic Performance: A Test of Alternative Propositions
ERIC Educational Resources Information Center
Bradley, Graham
2006-01-01
Increasing numbers of full-time university students mix their studies with paid employment. The current research examined the nature, extent and correlates of paid work amongst a sample of 246 university students. Approximately 85% of the sample reported having a paid job during semester, a figure that exceeds that found in previous studies. Five…
Refining a Competency Model for Instructional Designers in the Context of Online Higher Education
ERIC Educational Resources Information Center
Park, Jae-Young; Luo, Heng
2017-01-01
This study investigates the instructional designers (IDs) competencies essential for the context of online higher education, and has selected an instruction design unit in a research university as a case of investigation. To identify and compare IDs competencies at organizational and individual levels, this study employed a mixed method to collect…
ERIC Educational Resources Information Center
Qablan, Ahmad Mohammad; Al-Ruz, Jamal Abu; Khasawneh, Samer; Al-Omari, Aieman
2009-01-01
The purpose of this study was to investigate the attitudes and classroom practices of environmental science faculty members in Jordanian universities. Mix data collection methodology was employed to collect data in this study. In addition to the developed survey, several participants' interviews and classroom observations were conducted with…
Parametric Study of a Mixer/Ejector Nozzle with Mixing Enhancement Devices
NASA Technical Reports Server (NTRS)
DalBello, T.; Steffen, C. J., Jr.
2001-01-01
A numerical study employing a simplified model of the High Speed Civil Transport mixer/ejector nozzle has been conducted to investigate the effect of tabs (vortex generators) on the mixing process. More complete mixing of the primary and secondary flows within the confined ejector lowers peak exit velocity resulting in reduced jet noise. Tabs were modeled as vortex pairs and inserted into the computational model. The location, size, and number of tabs were varied and its effect on the mixing process is presented here both quantitatively and qualitatively. A baseline case (no tabs) along with six other cases involving two different vortex strengths at three different orientations have been computed and analyzed. The case with the highest vorticity (six vortices representing large tabs) gives the best mixing. It is shown that the influence of the vorticity acts primarily in the forward or middle portions of the duct, significantly alters the flow structure, and promotes some mixing in the lateral direction. Unmixed pockets were found at the top and bottom of the lobe, and more clever placement of tabs improved mixing in the vertical direction. The technique of replacing tabs with vortices shows promise as an efficient tool for quickly optimizing tab placement in lobed mixers.
Multi-monochromatic imaging of defect-induced mix experiments at OMEGA
NASA Astrophysics Data System (ADS)
Mancini, Roberto; Johns, Heather; Joshi, Tirtha; Mayes, Daniel; Durmaz, Tunay; Nagayama, Taisuke; Hsu, Scott; Tregillis, Ian; Krasheninnikova, Natalia; Cobble, James; Murphy, Thomas; Shah, Rahul; Kyrala, George; Hakel, Peter; Bradley, Paul; Schmitt, Mark
2012-10-01
In a series of polar-drive implosions performed at OMEGA for the defect-induced mix experiment (DIME) campaign of Los Alamos National Laboratory, two identical multi-monochromatic imager (MMI) instruments were fielded to record gated, x-ray spectrally-resolved images of D-filled Ti-doped plastic shells. The shells included a defect on the equatorial plane to study defect-induced mix while no-defect shells were employed in reference shots. The MMI data recorded simultaneously along quasi-orthogonal lines-of-sight afforded unique observations of the implosion based on the K-shell spectral signatures of the Ti tracer. Several analysis techniques have been used to process the MMI data (T. Nagayama et al, J. App. Phys. 109, 093303 (2011)) in order to study defect-induced mixing by tracking the spatial distribution and state of the tracer. Comparisons were made with results from post-processed 2D and 3D simulations to provide further insight into the interpretation of the experimental results and to constrain the simulation physics model.
Yang, Xinchao; Wang, Ke; Wang, Huijun; Zhang, Jianhua; Mao, Zhonggui
2016-11-01
An process of integrated ethanol-methane fermentation with improved economics has been studied extensively in recent years, where the process water used for a subsequent fermentation of carbohydrate biomass is recycled. This paper presents a systematic study of the ethanol fermentation characteristics of recycled process water. Compared with tap water, fermentation time was shortened by 40% when mixed water was employed. However, while the maximal ethanol production rate increased from 1.07g/L/h to 2.01g/L/h, ethanol production was not enhanced. Cell number rose from 0.6×10(8) per mL in tap water to 1.6×10(8) per mL in mixed water but although biomass increased, cell morphology was not affected. Furthermore, the use of mixed water increased the glycerol yield but decreased that of acetic acid, and the final pH with mixed water was higher than when using tap water. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, Dongdong; Tan, Jianguo; Lv, Liang
2015-12-01
The mixing process has been an important issue for the design of supersonic combustion ramjet engine, and the mixing efficiency plays a crucial role in the improvement of the combustion efficiency. In the present study, nanoparticle-based planar laser scattering (NPLS), particle image velocimetry (PIV) and large eddy simulation (LES) are employed to investigate the flow and mixing characteristics of supersonic mixing layer under different forced vibration conditions. The indexes of fractal dimension, mixing layer thickness, momentum thickness and scalar mixing level are applied to describe the mixing process. Results show that different from the development and evolution of supersonic mixing layer without vibration, the flow under forced vibration is more likely to present the characteristics of three-dimensionality. The laminar flow region of mixing layer under forced vibration is greatly shortened and the scales of rolled up Kelvin-Helmholtz vortices become larger, which promote the mixing process remarkably. The fractal dimension distribution reveals that comparing with the flow without vibration, the turbulent fluctuation of supersonic mixing layer under forced vibration is more intense. Besides, the distribution of mixing layer thickness, momentum thickness and scalar mixing level are strongly influenced by forced vibration. Especially, when the forcing frequency is 4000 Hz, the mixing layer thickness and momentum thickness are 0.0391 m and 0.0222 m at the far field of 0.16 m, 83% and 131% higher than that without vibration at the same position, respectively.
NASA Technical Reports Server (NTRS)
Lua, Yuan J.; Liu, Wing K.; Belytschko, Ted
1993-01-01
In this paper, the mixed boundary integral equation method is developed to study the elastic interactions of a fatigue crack and a micro-defect such as a void, a rigid inclusion or a transformation inclusion. The method of pseudo-tractions is employed to study the effect of a transformation inclusion. An enriched element which incorporates the mixed-mode stress intensity factors is applied to characterize the singularity at a moving crack tip. In order to evaluate the accuracy of the numerical procedure, the analysis of a crack emanating from a circular hole in a finite plate is performed and the results are compared with the available numerical solution. The effects of various micro-defects on the crack path and fatigue life are investigated. The results agree with the experimental observations.
Resource recycling technique of abandoned TNT-RDX-AL mixed explosive
NASA Astrophysics Data System (ADS)
Chen, Siyang; Ding, Yukui
2017-08-01
TNT-RDX-AL mixed explosive is a kind of high energy mixed explosive. It has the detonation characteristics even when reaching the scrapping standard. Inappropriate disposal often causes serious accident. Employing the resource recycling technique, the abandoned TNT-RDX-AL mixed explosive can be recycled. This paper summarized the progress of recycling of abandoned mixed explosive. What's more, three kinds of technological process of resource recycling abandoned TNT-RDX-AL mixed explosives are introduced. The author analysis of the current recovery processes and provided a reference for the recycling of the other same type explosive.
Brown, Judith; Neary, Joanne; Katikireddi, Srinivasa Vittal; Thomson, Hilary; McQuaid, Ronald W; Leyland, Alastair H; Frank, John; Jeavons, Luke; de Pellette, Paul; Kiran, Sibel; Macdonald, Ewan B
2015-12-16
Increasing employment among older workers is a policy priority given the increase in life expectancy and the drop in labour force participation after the age of 50. Reasons for this drop are complex but include poor health, age discrimination, inadequate skills/qualifications and caring roles; however, limited evidence exists on how best to support this group back to work. The Work Programme is the UK Government's flagship policy to facilitate return to work (RTW) among those at risk of long-term unemployment. 'Supporting Older People Into Employment' (SOPIE) is a mixed-methods longitudinal study involving a collaboration between academics and a major Work Programme provider (Ingeus). The study will investigate the relationship between health, worklessness and the RTW process for the over 50s. There are three main study components. Embedded fieldwork will document the data routinely collected by Ingeus and the key interventions/activities delivered. The quantitative study investigates approximately 14,000 individuals (aged 16-64 years, with 20% aged over 50) who entered the Ingeus Work Programme (referred to as 'clients') in a 16-month period in Scotland and were followed up for 2 years. Employment outcomes (including progression towards work) and how they differ by client characteristics (including health), intervention components received and external factors will be investigated. The qualitative component will explore the experiences of clients and Ingeus staff, to better understand the interactions between health and (un)employment, Work Programme delivery, and how employment services can be better tailored to the needs of the over 50s. Ethical approval was received from the University of Glasgow College of Social Sciences Research Ethics Committee (application number 400140186). Results will be disseminated through journal articles, national and international conferences. Findings will inform current and future welfare-to-work and job retention initiatives to extend healthy working lives. 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/
The Role of Principals in Professional Learning Communities
ERIC Educational Resources Information Center
Buttram, Joan L.; Farley-Ripple, Elizabeth N.
2016-01-01
The purpose of this article is to identify how principals shape the adoption and implementation of professional learning communities. The study employed a sequential mixed-methods approach in which interviews, observations, and document analysis informed survey design. Teachers were surveyed in four elementary schools about the practices and…
How College Students Conceptualize and Practice Responsible Drinking
ERIC Educational Resources Information Center
Barry, Adam E.; Goodson, Patricia
2011-01-01
Objective: This study sought to employ a mixed-methods approach to (a) qualitatively explore responsible drinking beliefs and behaviors among a sample of college students, and (b) quantitatively assess the prevalence of those behaviors. Participants: Convenience samples, drawn from currently enrolled students attending a large public university in…
Enhancing Digital Literacy and Learning among Adults with Blogs
ERIC Educational Resources Information Center
Sharp, Laurie A.
2017-01-01
Digital literacy and learning among adults has been identified as an area requiring research. The purpose of the present study was to explore technology acceptance and digital collaborative learning experiences with blogs among adult learners. This analysis employed a quasi-experimental mixed-methods approach guided by a sociocultural theoretical…
Digital Native Students: Gender Differences in Mathematics and Gaming
ERIC Educational Resources Information Center
Yong, Su-Ting
2017-01-01
The purpose of this study was to explore gender differences among digital native students in mathematics learning and gaming. A quantitative dominant mixed methods approach was employed in which quantitative surveys [174 students] and qualitative interviews [eight students, eight parents and six teachers] were administered concurrently. Data…
ERIC Educational Resources Information Center
Young, Adena Elizabeth
2010-01-01
The purpose of this dissertation was to examine metacognition among academically talented middle and high school mathematics students from both educational psychology and mathematics education perspectives. A synthesis of the literatures and three studies employing quantitative, qualitative, and mixed methodologies were used to address three…
Adult Professional Development: Can Brain-Based Teaching Strategies Increase Learning Effectiveness?
ERIC Educational Resources Information Center
Tilton, Wendy
2011-01-01
Brain-based teaching strategies, compared to facilitative student-centered teaching strategies, were employed with 62 real estate professionals in a quasi-mixed-methods study. Participants attended a 2-day proprietary real estate continuing education course. Both the experimental and control groups received the same facilitative instruction, as…
Gadgets in the Gymnasium: Physical Educators' Use of Digital Technologies
ERIC Educational Resources Information Center
Robinson, Daniel B.; Randall, Lynn
2017-01-01
This article highlights results from a recent study that investigated Atlantic Canadian physical educators' adoption and implementation of various digital technologies. Employing a mixed-methods research design (survey participants, n = 206; focus group participants, n = 12), the research intended to provide a clear overview of physical educators'…
Examining Stress in Graduate Assistants: Combining Qualitative and Quantitative Survey Methods
ERIC Educational Resources Information Center
Mazzola, Joseph J.; Walker, Erin J.; Shockley, Kristen M.; Spector, Paul E.
2011-01-01
The aim of this study was to employ qualitative and quantitative survey methods in a concurrent mixed model design to assess stressors and strains in graduate assistants. The stressors most frequently reported qualitatively were work overload, interpersonal conflict, and organizational constraints; the most frequently reported psychological…
Factors Affecting Middle School Students' Reading Motivation in Taiwan
ERIC Educational Resources Information Center
Huang, SuHua
2013-01-01
This study employed a triangulated mixed method to investigate reading motivation of Chinese middle school students in Taiwan. A total of 247 seventh grade students (122 boys and 125 girls) participated voluntarily by completing the Chinese Motivation for Research Questionnaire (CMRQ). Sixteen of the 247 students were purposely selected to…
ERIC Educational Resources Information Center
Moehle, Matthew R.
2011-01-01
As teacher education programs further emphasize clinical experiences, the role of university student teaching supervisor becomes increasingly important, as does research on supervision practices. Practitioners and researchers in the fields of positive psychology, management, and teacher education have argued that mentors who employ characteristics…
Teachers' Reactions towards Performance-Based Language Assessment
ERIC Educational Resources Information Center
Chinda, Bordin
2014-01-01
This research aims at examining the reactions of tertiary EFL teachers towards the use of performance-based language assessment. The study employed a mixed-method research methodology. For the quantitative method, 36 teachers responded to a questionnaire survey. In addition, four teachers participated in the in-depth interviews which were…
Numerical analysis of mixing enhancement for micro-electroosmotic flow
NASA Astrophysics Data System (ADS)
Tang, G. H.; He, Y. L.; Tao, W. Q.
2010-05-01
Micro-electroosmotic flow is usually slow with negligible inertial effects and diffusion-based mixing can be problematic. To gain an improved understanding of electroosmotic mixing in microchannels, a numerical study has been carried out for channels patterned with wall blocks, and channels patterned with heterogeneous surfaces. The lattice Boltzmann method has been employed to obtain the external electric field, electric potential distribution in the electrolyte, the flow field, and the species concentration distribution within the same framework. The simulation results show that wall blocks and heterogeneous surfaces can significantly disturb the streamlines by fluid folding and stretching leading to apparently substantial improvements in mixing. However, the results show that the introduction of such features can substantially reduce the mass flow rate and thus effectively prolongs the available mixing time when the flow passes through the channel. This is a non-negligible factor on the effectiveness of the observed improvements in mixing efficiency. Compared with the heterogeneous surface distribution, the wall block cases can achieve more effective enhancement in the same mixing time. In addition, the field synergy theory is extended to analyze the mixing enhancement in electroosmotic flow. The distribution of the local synergy angle in the channel aids to evaluate the effectiveness of enhancement method.
Employment of Low-Income African American and Latino Teens: Does Neighborhood Social Mix Matter?
Santiago, Anna; Lucero, Jessica
2014-01-01
We quantify how teen employment outcomes for low-income African Americans and Latinos relate to their neighborhood conditions during ages 14–17. Data come from surveys of Denver Housing Authority (DHA) households who have lived in public housing scattered throughout Denver County. Because DHA household allocation mimics random assignment to neighborhood, this program represents a natural experiment for overcoming geographic selection bias. Our logistic and Tobit regression analyses found overall greater odds of teen employment and more hours worked for those who lived in neighborhoods with higher percentages of pre-1940 vintage housing, property crime rates and child abuse rates, though the strength of relationships was highly contingent on gender and ethnicity. Teen employment prospects of African Americans were especially diminished by residence in more socially vulnerable, violent neighborhoods, implying selective potential gains from social mixing alternatives. PMID:26273120
The Relative Effectiveness of Women-Only and Mixed-Gender Treatment for Substance-Abusing Women
Prendergast, Michael L.; Messina, Nena P.; Hall, Elizabeth A.; Warda, Umme S.
2011-01-01
Following research indicating that the treatment needs of women are different from those of men, researchers and clinicians have argued that drug treatment programs for women should be designed to take their needs into account. Such programs tend to admit only women and incorporate philosophies and activities that are based on a social, peer-based model that is responsive to their needs. To assess the relative effectiveness of women-only (WO) outpatient programs compared to mixed-gender (MG) outpatient programs, 291 study volunteers were recruited (152 WO, 139 MG), and a 1-year follow-up was completed with 259 women (135 WO, 124 MG). Using bivariate, logistic regression, and generalized estimating equation analysis, the following four outcomes were examined: drug and alcohol use, criminal activity, arrests, and employment. In both groups, women showed improvement in the four outcome measures. Comparison of the groups on outcomes yielded mixed results; women who participated in WO treatment reported significantly less substance use and criminal activity than women in MG treatment, but there were no differences in arrest or employment status at follow up compared with those in MG treatment. PMID:21315540
Reproducing the old masters: applying colour mixing and painting methodologies to inkjet printing
NASA Astrophysics Data System (ADS)
Olen, Melissa; Padfield, Joseph; Parraman, Carinna
2014-01-01
This research investigates multi-channel inkjet printing methods, which deviate from standard colour management workflows by reflecting on art historical processes, including the construction of colour in old master works, to reproduce specific colour pigment mixes in print. This is approached by incorporating artist colour mixing principles relevant to traditional art making processes through direct n-channel printing and the implementation of multiple pass printing. By demanding specific ink colourants to be employed in print, as well as the application of mixing colour though layering, we can mimic the effects of the traditional processes. These printing methods also generate colour through a variety of colour mixtures that may not have been employed or achieved by the printer driver. The objective of this research is to explore colour mixing and layering techniques in the printing of inkjet reproductions of original artworks that will maintain subtle colour transitions in dark shadow regions. While these colours are lost in traditional inkjet reproduction, by using direct n-channel editing capabilities to reproduce a painted original with high dynamic range we can improve colour variation in the shadow regions.
Fabrication and characterization of mixed dye: Natural and synthetic organic dye
NASA Astrophysics Data System (ADS)
Richhariya, Geetam; Kumar, Anil
2018-05-01
Mixed dye from hibiscus sabdariffa and eosin Y was employed in the fabrication of dye sensitized solar cell (DSSC). Nanostructured mesoporous film was prepared from the titanium dioxide (TiO2). The energy conversion efficiency of hibiscus, eosin Y and mixed dye was obtained as 0.41%, 1.53% and 2.02% respectively. Mixed DSSC has shown improvement in the performance of the cell as compared to hibiscus and eosin Y dye due to addition of synthetic organic dye. This illustrates the effect of synthetic organic dyes in performance enhancement of natural dyes. It has been credited to the improved absorption of light mainly in higher energy state (λ = 440-560 nm) when two dyes were employed simultaneously as was obvious from the absorption spectra of dyes adsorbed onto TiO2 electrode. The cell with TiO2 electrode sensitized by mixed dye gives short circuit current density (Jsc) = 4.01 mA/cm2, open circuit voltage (Voc) = 0.67 V, fill factor (FF) = 0.60 and energy conversion efficiency (η) of 2.02%.
NASA Astrophysics Data System (ADS)
Mohammadpour, Raheleh
2017-12-01
Despite the wide application ranges of TiO2, the precise explanation of the charge transport dynamic through a mixed crystal phase of this semiconductor has remained elusive. Here, in this research, mixed-phase TiO2 nanotube arrays (TNTAs) consisting of anatase and 0-15% rutile phases has been formed through various annealing processes and employed as a photoelectrode of a photovoltaic cell. Wide ranges of optoelectronic experiments have been employed to explore the band alignment position, as well as the depth and density of trap states in TNTAs. Short circuit potential, as well as open circuit potential measurements specified that the band alignment of more than 0.2 eV exists between the anatase and rutile phase Fermi levels, with a higher electron affinity for anatase; this can result in a potential barrier in crystallite interfaces and the deterioration of electron mobility through mixed phase structures. Moreover, a higher density of shallow localized trap states below the conduction band with more depth (133 meV in anatase to 247 meV in 15% rutile phase) and also deep oxygen vacancy traps have been explored upon introducing the rutile phase. Based on our results, employing TiO2 nanotubes as just the electron transport medium in mixed crystalline phases can deteriorate the charge transport mechanism, however, in photocatalytic applications when both electrons and holes are present, a robust charge separation in crystalline anatase/rutile interphases will result in better performances.
Nickson, Dennis; Timming, Andrew R; Re, Daniel; Perrett, David I
2016-01-01
Using mixed design analysis of variance (ANOVA), this paper investigates the effects of a subtle simulated increase in adiposity on women's employment chances in the service sector. Employing a unique simulation of altering individuals' BMIs and the literature on "aesthetic labour", the study suggests that, especially for women, being heavier, but still within a healthy BMI, deleteriously impacts on hireability ratings. The paper explores the gendered dimension of this prejudice by asking whether female employees at the upper end of a healthy BMI range are likely to be viewed more negatively than their overtly overweight male counterparts. The paper concludes by considering the implications of these findings.
A Study of Developing Multicultural Awareness in Teacher Education: Watch, Write and Talk a Movie
ERIC Educational Resources Information Center
Karadeniz, Oguzhan; Incirci, Ayhan
2016-01-01
This study aimed to explore a valid and reliable way to raise the level of multiculturalism awareness of teachers. 61 (37 female, 24 male) trainee teachers from seven regions of Turkey attended the study. Mixed method (One group pretest-posttest design and content analysis) was employed to have better results. The results are; (1) the…
ERIC Educational Resources Information Center
Light, Richard L.; Harvey, Stephen; Memmert, Daniel
2013-01-01
This article builds upon research on youth sport clubs conducted from a socio-cultural perspective by reporting on a study that inquired into the reasons why children aged 9-12 joined swimming clubs in France, Germany and Australia. Comprising three case studies it employed a mixed method approach with results considered within the framework of…
ERIC Educational Resources Information Center
Ulubey, Özgür; Yildirim, Kasim; Alpaslan, Muhammet Mustafa; Aykaç, Necdet
2017-01-01
The purpose of the current study is to determine teachers' opinions about professional development schools. In the current study; one of the mixed methods, the convergent design was employed. The sampling of the quantitative dimension of the study is comprised of 256 teachers working in 21 elementary and secondary schools in the city of Mugla. The…
Deib, Gerard; Johnson, Alex; Unberath, Mathias; Yu, Kevin; Andress, Sebastian; Qian, Long; Osgood, Gregory; Navab, Nassir; Hui, Ferdinand; Gailloud, Philippe
2018-05-30
Optical see-through head mounted displays (OST-HMDs) offer a mixed reality (MixR) experience with unhindered procedural site visualization during procedures using high resolution radiographic imaging. This technical note describes our preliminary experience with percutaneous spine procedures utilizing OST-HMD as an alternative to traditional angiography suite monitors. MixR visualization was achieved using the Microsoft HoloLens system. Various spine procedures (vertebroplasty, kyphoplasty, and percutaneous discectomy) were performed on a lumbar spine phantom with commercially available devices. The HMD created a real time MixR environment by superimposing virtual posteroanterior and lateral views onto the interventionalist's field of view. The procedures were filmed from the operator's perspective. Videos were reviewed to assess whether key anatomic landmarks and materials were reliably visualized. Dosimetry and procedural times were recorded. The operator completed a questionnaire following each procedure, detailing benefits, limitations, and visualization mode preferences. Percutaneous vertebroplasty, kyphoplasty, and discectomy procedures were successfully performed using OST-HMD image guidance on a lumbar spine phantom. Dosimetry and procedural time compared favorably with typical procedural times. Conventional and MixR visualization modes were equally effective in providing image guidance, with key anatomic landmarks and materials reliably visualized. This preliminary study demonstrates the feasibility of utilizing OST-HMDs for image guidance in interventional spine procedures. This novel visualization approach may serve as a valuable adjunct tool during minimally invasive percutaneous spine treatment. © 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.
ERIC Educational Resources Information Center
Cooper, Nancy A.
2014-01-01
The primary intent of this study was to explore the effect between teachers' training, intervention strategies, and the academic achievement of K-5 ADHD students. The study design employed a mixed research design. The quantitative method focused on collecting data from certified regular and special-education teachers. Additionally, effects were…
ERIC Educational Resources Information Center
Dashtestani, Reza
2014-01-01
This study set out to explore Iranian English as a foreign language (EFL) teachers' perceptions on the implementation of online EFL instruction. A mixed-methods design, including semi-structured interviews and questionnaires, was employed for the specific purposes of this study. A total of 242 EFL teachers participated in the questionnaire phase…
ERIC Educational Resources Information Center
Cai, Shengrong; Zhu, Wei
2012-01-01
This study investigated the impact of an online learning community project on university students' motivation in learning Chinese as a foreign language. A newly proposed second language (L2) motivation theory--the L2 motivational self system (Dornyei, 2005, 2009)--guided this study. A concurrent transformative mixed-methods design was employed to…
ERIC Educational Resources Information Center
Busse, Vera; Walter, Catherine
2013-01-01
This article reports on a study involving first-year modern foreign languages students enrolled in German degree courses at two major universities in the United Kingdom. It explores the experience of these students from a motivational angle. A longitudinal mixed-methods approach was employed in order to address the time- and context-sensitive…
ERIC Educational Resources Information Center
Moorosi, Pontso; Bantwini, Bongani D.
2016-01-01
The purpose of this study was to investigate how leadership styles in the Eastern Cape school districts support school improvement. Mixed methods research was employed and data was collected through the use of questionnaires and semi-structured interviews with school principals in various districts. The study was guided by the following questions:…
ERIC Educational Resources Information Center
Sahin, Alpaslan; Top, Namik; Delen, Erhan
2016-01-01
Because mobile technology has become so obvious in a child's life, use of it for teaching and learning has become a necessity. This study investigates use of Chromebook laptops in 6-12 grade classrooms in relation to teachers' experience. We employ a mixed method approach. First, we study how teachers' years of teaching and numbers of…
Exploring the Oral Communication Strategies Used by Turkish EFL Learners: A Mixed Methods Study
ERIC Educational Resources Information Center
Demir, Yusuf; Mutlu, Gülçin; Sisman, Yavuz Selim
2018-01-01
This study set out with a threefold purpose: to examine (1) the oral communication strategies (CSs) employed by tertiary-level Turkish EFL learners, (2) the use of CSs based on exposure to English through audio-visual tools, university subject domain and gender differences, (3) the correlation between use of CSs and oral proficiency scores. To…
The Effect of Rehearsal Learning and Warm-up on the Speed of Different Swimming Strokes
ERIC Educational Resources Information Center
Magno, Carlo; Mascardo, Elizabeth
2009-01-01
The study investigated the effects of rehearsal learning and warm-up exercise on the time of performing different swimming strokes. The study was conducted among 202 college freshmen students taking up a course on physical education concentrated in swimming. The design employed is a mixed factorial (2 X 2) where time of swimming is measured before…
ERIC Educational Resources Information Center
Ültay, Eser; Alev, Nedim
2017-01-01
The purpose of this study was to investigate the effect of explanation assisted REACT strategy which was based on context-based learning approach on prospective science teachers' (PSTs) learning in impulse, momentum and collisions topics. The sequential explanatory strategy within mixed methods design was employed in this study. The first phase of…
ERIC Educational Resources Information Center
McAteer, Todd C.
2010-01-01
Purpose. The purpose of this study was to examine how knowledgeable teachers are in utilizing brain-researched instructional strategies. The research focused on determining which brain-researched strategies are implemented, the accuracy with which they are employed, and the degree to which they are utilized. A literature review revealed the most…
A Feasibility Study of Using ICT in Iranian Secondary Schools: The Case of Tehran Province
ERIC Educational Resources Information Center
Fathi Vajargah, Kourosh; Saadattlab, Ayat
2014-01-01
This research presents the results of a feasibility assessment on implementing ICT in Tehran high schools. Mixed method research (both qualitative and quantitative) was employed and due to the nature of research, data collection included two stages: library and field study. Using the cluster method with 362 subjects, data was collected using a…
"My Turn," Women's Goals and Motivations in a Diploma Program: A Constructive-Developmental Approach
ERIC Educational Resources Information Center
Drago-Severson, Eleanor
2014-01-01
This research was part of a larger, mixed-methods study, funded by the National Center for the Study of Adult Learning and Literacy, which examined the learning and change experiences of 41 learners in three ABE/ESOL programs. This paper examines a Polaroid diploma program with a focus on women workers, employing gender (relational) and…
ERIC Educational Resources Information Center
Novosel, Leslie C.
2012-01-01
Employing multiple methods, including a comparison group pre/posttest design and student interviews and self-reflections, this study represents an initial attempt to investigate the efficacy of a social and emotional learning self-regulation strategy relative to the general reading ability, reading self-concept, and social and emotional well-being…
A kinematic eddy viscosity model including the influence of density variations and preturbulence
NASA Technical Reports Server (NTRS)
Cohen, L. S.
1973-01-01
A model for the kinematic eddy viscosity was developed which accounts for the turbulence produced as a result of jet interactions between adjacent streams as well as the turbulence initially present in the streams. In order to describe the turbulence contribution from jet interaction, the eddy viscosity suggested by Prandtl was adopted, and a modification was introduced to account for the effect of density variation through the mixing layer. The form of the modification was ascertained from a study of the compressible turbulent boundary layer on a flat plate. A kinematic eddy viscosity relation which corresponds to the initial turbulence contribution was derived by employing arguments used by Prandtl in his mixing length hypothesis. The resulting expression for self-preserving flow is similar to that which describes the mixing of a submerged jet. Application of the model has led to analytical predictions which are in good agreement with available turbulent mixing experimental data.
Development of a new continuous process for mixing of complex non-Newtonian fluids
NASA Astrophysics Data System (ADS)
Migliozzi, Simona; Mazzei, Luca; Sochon, Bob; Angeli, Panagiota; Thames Multiphase Team; Coral Project Collaboration
2017-11-01
Design of new continuous mixing operations poses many challenges, especially when dealing with highly viscous non-Newtonian fluids. Knowledge of complex rheological behaviour of the working mixture is crucial for development of an efficient process. In this work, we investigate the mixing performance of two different static mixers and the effects of the mixture rheology on the manufacturing of novel non-aqueous-based oral care products using experimental and computational fluid dynamic methods. The two liquid phases employed, i.e. a carbomer suspension in polyethylene glycol and glycerol, start to form a gel when they mix. We studied the structure evolution of the liquid mixture using time-resolved rheometry and we obtained viscosity rheograms at different phase ratios from pressure drop measurements in a customized mini-channel. The numerical results and rheological model were validated with experimental measurements carried out in a specifically designed setup. EPSRS-CORAL.
NASA Astrophysics Data System (ADS)
Paul, Susmita; Choudhury, Amarjyoti
2014-10-01
Mixed phase nanocrystalline titania are prepared by simple sol-gel method. The physico-chemical characteristics of the prepared nanoparticles are studied with X-ray diffraction, high-resolution transmission electron microscopy, RAMAN, BET, UV-Vis, steady state and time resolved photoluminescence. X-ray diffraction and Raman spectra clearly demarcate the anatase and rutile phase as both the phases give different diffraction patterns and Raman peaks. A comparison in the band gap indicates that pure anatase and rutile phase have band gap in the UV region, whereas a mixture of these phases has lower band gap and corresponds to the visible region. Steady state and time resolved photoluminescence are employed to understand the emissivity and carrier lifetime. The photocatalytic activity is evaluated by monitoring the degradation of phenol under visible light illumination. Due to the synergistic effect of mixed anatase and rutile phases, mixed phase nanocrystalline titania exhibit superior photocatalytic activity.
Aguado Loi, Claudia X; Alfonso, Moya L; Chan, Isabella; Anderson, Kelsey; Tyson, Dinorah Dina Martinez; Gonzales, Junius; Corvin, Jaime
2017-08-01
The purpose of this paper is to share lessons learned from a collaborative, community-informed mixed-methods approach to adapting an evidence-based intervention to meet the needs of Latinos with chronic disease and minor depression and their family members. Mixed-methods informed by community-based participatory research (CBPR) were employed to triangulate multiple stakeholders' perceptions of facilitators and barriers of implementing the adapted intervention in community settings. Community partners provided an insider perspective to overcome methodological challenges. The study's community informed mixed-methods: research approach offered advantages to a single research methodology by expanding or confirming research findings and engaging multiple stakeholders in data collection. This approach also allowed community partners to collaborate with academic partners in key research decisions. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Cenedese, A.; Dore, V.; Moroni, M.
2009-05-01
Free thermal convection refers to the motion of vertical turbulent plumes or domes, which can occur when, an initially in-rest stratified fluid, is submitted to buoyancy forces, caused by a permanent perturbation associated to a heat transfer mechanism. When a fluid, in equilibrium, is stably stratified the external forcing can produce an unstable configuration ensuing the increasing in amplitude of internal waves, and, if it has strength enough, it can definitely erode the stratification, involving an increasing thickness of fluid volume. The entrainment phenomenon justifies the penetrative feature of convection and causes the growth of a convective boundary layer of well mixed fluid (Convective Mixing Layer) against the adjacent stable stratified layer. The non-steady phenomenon of penetrative convection in a stably stratified fluid has been reproduced in laboratory employing a tank filled with water and subjected to heating from below. The goal in the experiment is predicting the convective boundary layer growth as a function of initial and boundary conditions and describing the fate of a tracer dissolved in the fluid phase. The motivations of the research are mostly related to its connections to environmental topics. In nature the dynamics of penetrative convection influences the transport and mixing features of stratified fluids, playing a fundamental role in characterizing and forecasting the distribution of chemical species, with implication for water or air quality in the upper oceans and lakes or in the lower troposphere. When studying turbulent convective phenomenon, dispersion is mostly due to transport by large organized structures while molecular diffusion can be neglected. The knowledge of the horizontal and vertical extension of the structures dominating the flow field appears to be mandatory. In order to better understanding and likely describing the evolution of turbulent structures inside the convective layer, a fully three dimensional experimental technique is required. The equipment employed is suitable for simultaneously providing temperatures inside the domain through thermocouples and Lagrangian particle trajectories obtained by using a 3D-PTV technique. The combined use of a vertical array of thermocouples and 3D-PTV allows, simultaneously, profiling temperature and the 3D velocity components. A properly calibrated stereoscopic system of three monochrome 25 fps CCD cameras has been employed. The combination of image and object space based information is applied to establish the spatio-temporal correspondences between particle position of consecutive time steps, resulting in the reconstruction of 3D trajectories. The vertical dimension of convective structures is associated to the mixing layer height, detected both employing temperature data and statistics of the velocity field. On the other hand, the spatial correlation of the velocity field, providing the plume horizontal dimension, allows the horizontal extension of the mixing region to be determined. This information coupled to the knowledge of the mixing layer height allows the spatial extension of the convective region to be fully described.
Diffusely reflecting paints including polytetrafluoroethylene and method of manufacture
NASA Technical Reports Server (NTRS)
Schutt, J. B.; Shai, M. C. (Inventor)
1985-01-01
The invention pertains to a high diffuse, reflective paint comprising an alcohol soluble binder, polytetrafluoroethylene (TFE) and an alcohol for coating a substrate and forming an optical reference with a superior Lambertian characteristic. A method for making the paint by first mixing the biner and alcohol, and thereafter by mixing in outgassed TFE is described. A wetting agent may be employed to aid the mixing process.
What Are You? A CRT Perspective on the Experiences of Mixed Race Persons in "Post-Racial" America
ERIC Educational Resources Information Center
Anderson, Celia Rousseau
2015-01-01
In this article, the author employs Critical Race Theory (CRT) to examine the experiences of mixed race individuals in the United States. Drawing on historical and contemporary conditions involving persons of mixed race, the author considers how key ideas from CRT can be useful to frame an analysis of the experiences of multiracial persons in the…
NASA Technical Reports Server (NTRS)
Tamma, Kumar K.; D'Costa, Joseph F.
1991-01-01
This paper describes the evaluation of mixed implicit-explicit finite element formulations for hyperbolic heat conduction problems involving non-Fourier effects. In particular, mixed implicit-explicit formulations employing the alpha method proposed by Hughes et al. (1987, 1990) are described for the numerical simulation of hyperbolic heat conduction models, which involves time-dependent relaxation effects. Existing analytical approaches for modeling/analysis of such models involve complex mathematical formulations for obtaining closed-form solutions, while in certain numerical formulations the difficulties include severe oscillatory solution behavior (which often disguises the true response) in the vicinity of the thermal disturbances, which propagate with finite velocities. In view of these factors, the alpha method is evaluated to assess the control of the amount of numerical dissipation for predicting the transient propagating thermal disturbances. Numerical test models are presented, and pertinent conclusions are drawn for the mixed-time integration simulation of hyperbolic heat conduction models involving non-Fourier effects.
Mixing medication into foodstuffs: identifying the issues for paediatric nurses.
Akram, Gazala; Mullen, Alex B
2015-04-01
Medication is often mixed into soft foods to aid swallowing in children. However, this can alter the physical/chemical properties of the active drug. This study reports on the prevalence of the modification procedure, the nature of foodstuffs routinely used and factors which influence how the procedure is performed by nurses working in the National Health Service in Scotland. Mixed methods were employed encompassing an online self-administered questionnaire and semi-structured interviews. One hundred and eleven nurses participated, of whom 87% had modified medication prior to administration. Fruit juice (diluted and concentrated) and yoghurts were most commonly used. The interviews (i) identified the limitations of the procedure; (ii) explored the decision-making process; and (iii) confirmed the procedure was a last resort. This study intends to address some of the uncertainty surrounding the medicine modification procedure within the paediatric population. © 2013 Wiley Publishing Asia Pty Ltd.
A DNS study of turbulent mixing of two passive scalars
NASA Astrophysics Data System (ADS)
Juneja, A.; Pope, S. B.
1996-08-01
We employ direct numerical simulations to study the mixing of two passive scalars in stationary, homogeneous, isotropic turbulence. The present work is a direct extension of that of Eswaran and Pope from one scalar to two scalars and the focus is on examining the evolution states of the scalar joint probability density function (jpdf) and the conditional expectation of the scalar diffusion to motivate better models for multi-scalar mixing. The initial scalar fields are chosen to conform closely to a ``triple-delta function'' jpdf corresponding to blobs of fluid in three distinct states. The effect of the initial length scales and diffusivity of the scalars on the evolution of the jpdf and the conditional diffusion is investigated in detail as the scalars decay from their prescribed initial state. Also examined is the issue of self-similarity of the scalar jpdf at large times and the rate of decay of the scalar variance and dissipation.
ERIC Educational Resources Information Center
Cavanaugh, Andrew; Song, Liyan
2015-01-01
This study investigated students' and instructors' approaches and preferences to audio and written comments in an online undergraduate composition class. A mixed-method design was employed utilizing both a survey instrument and interviews for data collection. Forty-nine students and five instructors participated. Students gave more positive…
A Song to Remember: Emerging Adults Recall Memorable Music
ERIC Educational Resources Information Center
Lippman, Julia R.; Greenwood, Dara N.
2012-01-01
The present study employs a mixed methods approach to understanding the psychological functions and contexts of music use. Seventy-six emerging adults selected a single piece of music that they considered personally significant and elaborated on the reasons for this significance in response to written prompts. A constant comparative analysis of…
Effects of Numeric Representation of Women on Interest in Engineering as a Career
ERIC Educational Resources Information Center
Creamer, Elizabeth G.
2012-01-01
Little is known about how the presence of women influences undergraduates' experiences in engineering. This paper presents results from a mixed methods, multivariate, and multi-institutional study to determine the impact of the numeric representation of women on the intent to be employed in engineering following graduation. Results from the…
"We Don't Know Enough": Environmental Education and Pro-Environmental Behaviour Perceptions
ERIC Educational Resources Information Center
Ajaps, Sandra; McLellan, Ros
2015-01-01
This study sought to understand environmental knowledge and attitudes among young people to explain the relationship between environmental education (EE) and reported pro-environmental behaviours (PEB). A mixed-methods design was employed: 88 university students in the UK and Nigeria were surveyed and 6 were subsequently interviewed. The findings…
Chinese Teachers' Work Stress and Their Turnover Intention
ERIC Educational Resources Information Center
Liu, Shujie; Onwuegbuzie, Anthony J.
2012-01-01
This survey study employed qualitative dominant mixed research to explore the sources of teacher stress in China and the possible reasons for Chinese teachers' turnover intention. The data were collected in Jilin Province of China, and 510 teachers participated in the survey. Quantitatively, 40.4% of the surveyed teachers reported that they…
The Use of a Computer Simulation to Promote Conceptual Change: A Quasi-Experimental Study
ERIC Educational Resources Information Center
Trundle, Kathy Cabe; Bell, Randy L.
2010-01-01
This mixed-methods investigation compared the effectiveness of three instructional approaches in achieving desired conceptual change among early childhood preservice teachers (n = 157). Each of the three treatments employed inquiry-based instruction on moon phases using data collected from: (1) the planetarium software program, Starry Night[TM],…
Choosing the Optimum Mix of Duration and Effort in Education.
ERIC Educational Resources Information Center
Oosterbeek, Hessel
1995-01-01
Employs a simple economic model to analyze determinants of Dutch college students' expected study duration and weekly effort. Findings show that the duration/effort ratio is determined by the relative prices of these inputs into the learning process. A higher socioeconomic status increases the duration/effort ratio. Higher ability levels decrease…
ERIC Educational Resources Information Center
Hinkson, Chandris Christina
2010-01-01
The purpose of this mixed methods study was to examine continuing education students' perceptions of adult education instructional practices at an urban community college. The continuing education students recently graduated from programs of law enforcement, truck driving, and health occupations. Perception analysis was based on the six principles…
NASA Technical Reports Server (NTRS)
Hong, Z. C.
1975-01-01
A review of various methods of calculating turbulent chemically reacting flow such as the Green Function, Navier-Stokes equation, and others is presented. Nonequilibrium degrees of freedom were employed to study the mixing behavior of a multiscale turbulence field. Classical and modern theories are discussed.
Integrating Wikis as Educational Tools for the Development of a Community of Inquiry
ERIC Educational Resources Information Center
Eteokleous, Nikleia; Ktoridou, Despo; Orphanou, Maria
2014-01-01
This article describes a study that attempted to evaluate the integration of wikis as an educational tool in successfully achieving the learning objectives of a fifth-grade linguistics and literature course. A mixed-method approach was employed--data were collected via questionnaires, reflective journals, observations, and interviews. The results…
Examining the Influence of Educational Mobile Application Software on Students' Technology Literacy
ERIC Educational Resources Information Center
Twu, Ming-Lii
2017-01-01
The purpose of this mixed methods study was to employ the International Society for Technology in Education (ISTE) Standards for Students as taxonomy to classify educational mobile application (app) software into seven categories and empirically examine the influence on students' technology literacy. A purposeful sample of fifth grade core subject…
The Effect of Appreciative Inquiry on Student Engagement and Attendance in the Community College
ERIC Educational Resources Information Center
Robbins, Frances Virginia Turner
2012-01-01
This mixed-methods research study investigated the effects of Appreciative Inquiry on student-course engagement and attendance in core academic classes at a community college in central Mississippi. In an increasingly competitive global economy, most individuals need education or technical skills beyond high school to secure employment offering…
ERIC Educational Resources Information Center
Larson, Lincoln R.; Green, Gary T.; Castleberry, Steven B.
2011-01-01
An understanding of children's environmental orientations is of critical importance as opportunities for authentic contact with nature diminish. Current instruments for measuring children's environmental attitudes are complex, and few have been tested across diverse audiences. This study employed a mixed-methods approach that included pilot tests,…
Making Sense of the Combined Degree Experience: The Example of Criminology Double Degrees
ERIC Educational Resources Information Center
Wimshurst, Kerry; Manning, Matthew
2017-01-01
Little research has been undertaken on student experiences of combined degrees. The few studies report that a considerable number of students experienced difficulty with the contrasting epistemic/disciplinary demands of the component programmes. A mixed-methods approach was employed to explore the experiences of graduates from four double degrees…
Students' Learning Outcomes and Learning Experiences through Playing a Serious Educational Game
ERIC Educational Resources Information Center
Cheng, Meng-Tzu; Annetta, Len
2012-01-01
This study attempted to examine students' learning outcomes and their learning experiences through playing a Serious Educational Game. A mixed-method research design was employed collecting both quantitative and qualitative data. A total of 98 middle-school students ranging from sixth to eighth grades participated through paper-and-pencil…
Guilty in Whose Eyes? Student-Teachers' Perspectives on Cheating on Examinations
ERIC Educational Resources Information Center
Amua-Sekyi, Ekua Tekyiwa
2016-01-01
The study explored student-teachers' views on cheating during examinations. A mixed method approach which involved a survey and focus group interviews was employed. Nine hundred undergraduate education students from a public university and three colleges of education in Ghana were surveyed. Focus group interviews were held with six students from…
ERIC Educational Resources Information Center
Rebello, Carina M.
2012-01-01
This study explored the effects of alternative forms of argumentation on undergraduates' physics solutions in introductory calculus-based physics. A two-phase concurrent mixed methods design was employed to investigate relationships between undergraduates' written argumentation abilities, conceptual quality of problem solutions, as well…
Graduate Attribute Attainment in a Multi-Level Undergraduate Geography Course
ERIC Educational Resources Information Center
Mager, Sarah; Spronken-Smith, Rachel
2014-01-01
We investigated students' perceptions of graduate attributes in a multi-level (second and third year) geography course. A case study with mixed methodology was employed, with data collected through focus groups and a survey. We found that undergraduate geography students can identify the skills, knowledge and attributes that are developed through…
Mixing and transient interface condensation of a liquid hydrogen tank
NASA Technical Reports Server (NTRS)
Lin, C. S.; Hasan, M. M.; Nyland, T. W.
1993-01-01
Experiments were conducted to investigate the effect of axial jet-induced mixing on the pressure reduction of a thermally stratified liquid hydrogen tank. The tank was nearly cylindrical, having a volume of about 0.144 cu m with 0.559 m in diameter and 0.711 m length. A mixer/pump unit, which had a jet nozzle outlet of 0.0221 m in diameter was located 0.178 m from the tank bottom and was installed inside the tank to generate the axial jet mixing and tank fluid circulation. Mixing tests began with the tank pressures at which the thermal stratification results in 4.9-6.2 K liquid subcooling. The mixing time and transient vapor condensation rate at the liquid-vapor interface are determined. Two mixing time correlations, based on the thermal equilibrium and pressure equilibrium, are developed and expressed as functions of system and buoyancy parameters. The limited liquid hydrogen data of the present study shows that the modified steady state condensation rate correlation may be used to predict the transient condensation rate in a mixing process if the instantaneous values of jet sub cooling and turbulence intensity at the interface are employed.
A Lagrangian mixing frequency model for transported PDF modeling
NASA Astrophysics Data System (ADS)
Turkeri, Hasret; Zhao, Xinyu
2017-11-01
In this study, a Lagrangian mixing frequency model is proposed for molecular mixing models within the framework of transported probability density function (PDF) methods. The model is based on the dissipations of mixture fraction and progress variables obtained from Lagrangian particles in PDF methods. The new model is proposed as a remedy to the difficulty in choosing the optimal model constant parameters when using conventional mixing frequency models. The model is implemented in combination with the Interaction by exchange with the mean (IEM) mixing model. The performance of the new model is examined by performing simulations of Sandia Flame D and the turbulent premixed flame from the Cambridge stratified flame series. The simulations are performed using the pdfFOAM solver which is a LES/PDF solver developed entirely in OpenFOAM. A 16-species reduced mechanism is used to represent methane/air combustion, and in situ adaptive tabulation is employed to accelerate the finite-rate chemistry calculations. The results are compared with experimental measurements as well as with the results obtained using conventional mixing frequency models. Dynamic mixing frequencies are predicted using the new model without solving additional transport equations, and good agreement with experimental data is observed.
Geometric multiaxial representation of N -qubit mixed symmetric separable states
NASA Astrophysics Data System (ADS)
SP, Suma; Sirsi, Swarnamala; Hegde, Subramanya; Bharath, Karthik
2017-08-01
The study of N -qubit mixed symmetric separable states is a longstanding challenging problem as no unique separability criterion exists. In this regard, we take up the N -qubit mixed symmetric separable states for a detailed study as these states are of experimental importance and offer an elegant mathematical analysis since the dimension of the Hilbert space is reduced from 2N to N +1 . Since there exists a one-to-one correspondence between the spin-j system and an N -qubit symmetric state, we employ Fano statistical tensor parameters for the parametrization of the spin-density matrix. Further, we use a geometric multiaxial representation (MAR) of the density matrix to characterize the mixed symmetric separable states. Since the separability problem is NP-hard, we choose to study it in the continuum limit where mixed symmetric separable states are characterized by the P -distribution function λ (θ ,ϕ ) . We show that the N -qubit mixed symmetric separable states can be visualized as a uniaxial system if the distribution function is independent of θ and ϕ . We further choose a distribution function to be the most general positive function on a sphere and observe that the statistical tensor parameters characterizing the N -qubit symmetric system are the expansion coefficients of the distribution function. As an example for the discrete case, we investigate the MAR of a uniformly weighted two-qubit mixed symmetric separable state. We also observe that there exists a correspondence between the separability and classicality of states.
Assessing the impact of obesity on labor market outcomes.
Lindeboom, Maarten; Lundborg, Petter; van der Klaauw, Bas
2010-12-01
We study the effect of obesity on employment, using rich data from the British National Child Development Study (NCDS). The results show a significant negative association between obesity and employment even after controlling for a rich set of demographic, socioeconomic, environmental and behavioral variables. In order to account for the endogeneity of obesity, we use and assess instruments introduced by Cawley (2004); the obesity status of biological relatives. Using parental obesity as an instrument, we show that the association between obesity and employment is no longer significant. Similar results are obtained in a model of first differences. We provide a number of different checks on the instruments, by exploiting the richness of the NCDS data. The results show mixed evidence regarding the validity of the instruments. Copyright © 2010 Elsevier B.V. All rights reserved.
High linearity current communicating passive mixer employing a simple resistor bias
NASA Astrophysics Data System (ADS)
Rongjiang, Liu; Guiliang, Guo; Yuepeng, Yan
2013-03-01
A high linearity current communicating passive mixer including the mixing cell and transimpedance amplifier (TIA) is introduced. It employs the resistor in the TIA to reduce the source voltage and the gate voltage of the mixing cell. The optimum linearity and the maximum symmetric switching operation are obtained at the same time. The mixer is implemented in a 0.25 μm CMOS process. The test shows that it achieves an input third-order intercept point of 13.32 dBm, conversion gain of 5.52 dB, and a single sideband noise figure of 20 dB.
ERIC Educational Resources Information Center
Albayrak, Duygu; Yildirim, Zahide
2015-01-01
This study investigates students' involvement in Facebook® as a course management system (CMS), Facebook acceptance, and the relationships between the two. The study used Facebook as a CMS in two freshman courses and employed mixed method as part of an action-research approach. Forty-two students participated in the study, and 12 of those students…
Scalar transport in inline mixers with spatially periodic flows
NASA Astrophysics Data System (ADS)
Baskan, Ozge; Rajaei, Hadi; Speetjens, Michel F. M.; Clercx, Herman J. H.
2017-01-01
Spatially persisting patterns form during the downstream evolution of passive scalars in three-dimensional (3D) spatially periodic flows due to the coupled effect of stretching and folding mechanisms of the flow field. This has been investigated in many computational and theoretical studies of 2D time-periodic and 3D spatially periodic flow fields. However, experimental studies, to date, have mainly focused on flow visualization with streaks of dye rather than fully 3D scalar field measurements. Our study employs 3D particle tracking velocimetry and 3D laser-induced fluorescence to analyze the evolution of 3D flow and scalar fields and the correlation between the coherent flow/scalar field structures in a representative inline mixer, the Quatro static mixer. For this purpose an experimental setup that consists of an optically accessible test section with transparent internal elements accommodating a pressure-driven pipe flow has been built. The flow and scalar fields clearly underline the complementarity of the experimental results with numerical simulations and provide validation of the periodicity assumption needed in numerical studies. The experimental procedure employed in this investigation, which allows studying the scalar transport in the advective limit, demonstrates the suitability of the present method for exploratory mixing studies of a variety of mixing devices, beyond the Quatro static mixer.
Zeeshan, Farrukh; Tabbassum, Misbah; Jorgensen, Lene; Medlicott, Natalie J
2018-02-01
Protein drugs may encounter conformational perturbations during the formulation processing of lipid-based solid dosage forms. In aqueous protein solutions, attenuated total reflection Fourier transform infrared (ATR FT-IR) spectroscopy can investigate these conformational changes following the subtraction of spectral interference of solvent with protein amide I bands. However, in solid dosage forms, the possible spectral contribution of lipid carriers to protein amide I band may be an obstacle to determine conformational alterations. The objective of this study was to develop an ATR FT-IR spectroscopic method for the analysis of protein secondary structure embedded in solid lipid matrices. Bovine serum albumin (BSA) was chosen as a model protein, while Precirol AT05 (glycerol palmitostearate, melting point 58 ℃) was employed as the model lipid matrix. Bovine serum albumin was incorporated into lipid using physical mixing, melting and mixing, or wet granulation mixing methods. Attenuated total reflection FT-IR spectroscopy and size exclusion chromatography (SEC) were performed for the analysis of BSA secondary structure and its dissolution in aqueous media, respectively. The results showed significant interference of Precirol ATO5 with BSA amide I band which was subtracted up to 90% w/w lipid content to analyze BSA secondary structure. In addition, ATR FT-IR spectroscopy also detected thermally denatured BSA solid alone and in the presence of lipid matrix indicating its suitability for the detection of denatured protein solids in lipid matrices. Despite being in the solid state, conformational changes occurred to BSA upon incorporation into solid lipid matrices. However, the extent of these conformational alterations was found to be dependent on the mixing method employed as indicated by area overlap calculations. For instance, the melting and mixing method imparted negligible effect on BSA secondary structure, whereas the wet granulation mixing method promoted more changes. Size exclusion chromatography analysis depicted the complete dissolution of BSA in the aqueous media employed in the wet granulation method. In conclusion, an ATR FT-IR spectroscopic method was successfully developed to investigate BSA secondary structure in solid lipid matrices following the subtraction of lipid spectral interference. The ATR FT-IR spectroscopy could further be applied to investigate the secondary structure perturbations of therapeutic proteins during their formulation development.
Investigating Learning with an Interactive Tutorial: A Mixed-Methods Strategy
ERIC Educational Resources Information Center
de Villiers, M. R.; Becker, Daphne
2017-01-01
From the perspective of parallel mixed-methods research, this paper describes interactivity research that employed usability-testing technology to analyse cognitive learning processes; personal learning styles and times; and errors-and-recovery of learners using an interactive e-learning tutorial called "Relations." "Relations"…
NASA Technical Reports Server (NTRS)
Koshak, William; Solakiewicz, Richard
2012-01-01
The ability to estimate the fraction of ground flashes in a set of flashes observed by a satellite lightning imager, such as the future GOES-R Geostationary Lightning Mapper (GLM), would likely improve operational and scientific applications (e.g., severe weather warnings, lightning nitrogen oxides studies, and global electric circuit analyses). A Bayesian inversion method, called the Ground Flash Fraction Retrieval Algorithm (GoFFRA), was recently developed for estimating the ground flash fraction. The method uses a constrained mixed exponential distribution model to describe a particular lightning optical measurement called the Maximum Group Area (MGA). To obtain the optimum model parameters (one of which is the desired ground flash fraction), a scalar function must be minimized. This minimization is difficult because of two problems: (1) Label Switching (LS), and (2) Parameter Identity Theft (PIT). The LS problem is well known in the literature on mixed exponential distributions, and the PIT problem was discovered in this study. Each problem occurs when one allows the numerical minimizer to freely roam through the parameter search space; this allows certain solution parameters to interchange roles which leads to fundamental ambiguities, and solution error. A major accomplishment of this study is that we have employed a state-of-the-art genetic-based global optimization algorithm called Differential Evolution (DE) that constrains the parameter search in such a way as to remove both the LS and PIT problems. To test the performance of the GoFFRA when DE is employed, we applied it to analyze simulated MGA datasets that we generated from known mixed exponential distributions. Moreover, we evaluated the GoFFRA/DE method by applying it to analyze actual MGAs derived from low-Earth orbiting lightning imaging sensor data; the actual MGA data were classified as either ground or cloud flash MGAs using National Lightning Detection Network[TM] (NLDN) data. Solution error plots are provided for both the simulations and actual data analyses.
An epidemic model to evaluate the homogeneous mixing assumption
NASA Astrophysics Data System (ADS)
Turnes, P. P.; Monteiro, L. H. A.
2014-11-01
Many epidemic models are written in terms of ordinary differential equations (ODE). This approach relies on the homogeneous mixing assumption; that is, the topological structure of the contact network established by the individuals of the host population is not relevant to predict the spread of a pathogen in this population. Here, we propose an epidemic model based on ODE to study the propagation of contagious diseases conferring no immunity. The state variables of this model are the percentages of susceptible individuals, infectious individuals and empty space. We show that this dynamical system can experience transcritical and Hopf bifurcations. Then, we employ this model to evaluate the validity of the homogeneous mixing assumption by using real data related to the transmission of gonorrhea, hepatitis C virus, human immunodeficiency virus, and obesity.
Numerical simulation of mechanical mixing in high solid anaerobic digester.
Yu, Liang; Ma, Jingwei; Chen, Shulin
2011-01-01
Computational fluid dynamics (CFD) was employed to study mixing performance in high solid anaerobic digester (HSAD) with A-310 impeller and helical ribbon. A mathematical model was constructed to assess flow fields. Good agreement of the model results with experimental data was obtained for the A-310 impeller. A systematic comparison for the interrelationship of power number, flow number and Reynolds number was simulated in a digester with less than 5% TS and 10% TS (total solids). The simulation results suggested a great potential for using the helical ribbon mixer in the mixing of high solids digester. The results also provided quantitative confirmation for minimum power consumption in HSAD and the effect of share rate on bio-structure. Copyright © 2010 Elsevier Ltd. All rights reserved.
Zhang, Jian-Hua; Zeng, Xin; Chen, Xu-Sheng; Mao, Zhong-Gui
2018-04-21
The glucose-glycerol mixed carbon source remarkably reduced the batch fermentation time of ε-poly-L-lysine (ε-PL) production, leading to higher productivity of both biomass and ε-PL, which was of great significance in industrial microbial fermentation. Our previous study confirmed the positive influence of fast cell growth on the ε-PL biosynthesis, while the direct influence of mixed carbon source on ε-PL production was still unknown. In this work, chemostat culture was employed to study the capacity of ε-PL biosynthesis in different carbon sources at a same dilution rate of 0.05 h -1 . The results indicated that the mixed carbon source could enhance the ε-PL productivity besides the rapid cell growth. Analysis of key enzymes demonstrated that the activities of phosphoenolpyruvate carboxylase, citrate synthase, aspartokinase and ε-PL synthetase were all increased in chemostat culture with the mixed carbon source. In addition, the carbon fluxes were also improved in the mixed carbon source in terms of tricarboxylic acid cycle, anaplerotic and diaminopimelate pathway. Moreover, the mixed carbon source also accelerated the energy metabolism, leading to higher levels of energy charge and NADH/NAD + ratio. The overall improvements of primary metabolism in chemostat culture with glucose-glycerol combination provided sufficient carbon skeletons and ATP for ε-PL biosynthesis. Therefore, the significantly higher ε-PL productivity in the mixed carbon source was a combined effect of both superior substrate group and rapid cell growth.
NASA Astrophysics Data System (ADS)
Malathy Devi, V.; Benner, D. Chris; Kleiner, Isabelle; Sams, Robert L.; Fletcher, Leigh N.
2014-08-01
Accurate knowledge of spectroscopic line parameters of PH3 is important for remote sensing of the outer planets, especially Jupiter and Saturn. In a recent study, line positions and intensities for the Pentad bands of PH3 have been reported from analysis of high-resolution, high signal-to noise room-temperature spectra recorded with two Fourier transform spectrometers (2014) [1]. The results presented in this study were obtained during the analysis of positions and intensities, but here we focus on the measurements of spectral line shapes (e.g. widths, shifts, line mixing) for the 2ν4, ν2 + ν4, ν1 and ν3 bands. A multispectrum nonlinear least squares curve fitting technique employing a non-Voigt line shape to include line mixing and speed dependence of the Lorentz width was employed to fit the spectra simultaneously. The least squares fittings were performed on five room-temperature spectra recorded at various PH3 pressures (∼2-50 Torr) with the Bruker IFS-125HR Fourier transform spectrometer (FTS) located at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington. Over 840 Lorentz self-broadened half-width coefficients, 620 self-shift coefficients and 185 speed dependence parameters were measured. Line mixing was detected for transitions in the 2ν4, ν1 and ν3 bands, and their values were quantified for 10 A+A- pairs of transitions via off-diagonal relaxation matrix element formalism. The dependences of the measured half-width coefficients on the J and K rotational quanta of the transitions are discussed. The self-width coefficients for the ν1 and ν3 bands from this study are compared to the self-width coefficients for transitions with the same rotational quanta (J, K) reported for the Dyad (ν2 and ν4) bands. The measurements from present study should be useful for the development of a reliable theoretical modeling of pressure-broadened widths, shifts and line mixing in symmetric top molecules with C3v symmetry in general, and of PH3 in particular.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malathy Devi, V.; Benner, D. C.; Kleiner, Isabelle
2014-08-01
Accurate knowledge of spectroscopic line parameters of PH 3 is important for remote sensing of the outer planets, especially Jupiter and Saturn. In a recent study, line positions and intensities for the Pentad bands of PH 3 have been reported from analysis of high-resolution, high signal-to noise room-temperature spectra recorded with two Fourier transform spectrometers (2014) [1]. The results presented in this study were obtained during the analysis of positions and intensities, but here we focus on the measurements of spectral line shapes (e.g. widths, shifts, line mixing) for the 2ν 4, ν 2 + ν 4, ν 1 andmore » ν 3 bands. A multispectrum nonlinear least squares curve fitting technique employing a non-Voigt line shape to include line mixing and speed dependence of the Lorentz width was employed to fit the spectra simultaneously. The least squares fittings were performed on five room-temperature spectra recorded at various PH 3 pressures (~2–50 Torr) with the Bruker IFS-125HR Fourier transform spectrometer (FTS) located at the Pacific Northwest National Laboratory (PNNL), in Richland, Washington. Over 840 Lorentz self-broadened half-width coefficients, 620 self-shift coefficients and 185 speed dependence parameters were measured. Line mixing was detected for transitions in the 2ν 4, ν 1 and ν 3 bands, and their values were quantified for 10 A+A- pairs of transitions via off-diagonal relaxation matrix element formalism. The dependences of the measured half-width coefficients on the J and K rotational quanta of the transitions are discussed. The self-width coefficients for the ν 1 and ν 3 bands from this study are compared to the self-width coefficients for transitions with the same rotational quanta (J, K) reported for the Dyad (ν 2 and ν 4) bands. The measurements from present study should be useful for the development of a reliable theoretical modeling of pressure-broadened widths, shifts and line mixing in symmetric top molecules with C 3v symmetry in general, and of PH 3 in particular.« less
ERIC Educational Resources Information Center
Longbotham, Pamela J.
2012-01-01
The study examined the impact of participation in an optional flexible year program (OFYP) on academic achievement. The ex post facto study employed an explanatory sequential mixed methods design. The non-probability sample consisted of 163 fifth grade students in an OFYP district and 137 5th graders in a 180-day instructional year school…
ERIC Educational Resources Information Center
Kuwahara, Natsuko
2010-01-01
The present study employed a mixed methods approach to explore well-being, quality of life and experiences among Japanese sojourner graduate students studying in the U.S. utilizing 155 survey responses and 39 in-depth individual interviews. Key measures used include: the K6 screen for risk of serious mental illness (K6) (Kessler et al., 2002), the…
ERIC Educational Resources Information Center
Ugwuanyi, L. T.; Adaka, T. A.
2015-01-01
The paper focused on the effect of auditory training on reading comprehension of children with hearing impairment in Enugu State. A total of 33 children with conductive, sensory neural and mixed hearing loss were sampled for the study in the two schools for the Deaf in Enugu State. The design employed for the study was a quasi experiment (pre-test…
ERIC Educational Resources Information Center
Çakir, Abdulvahit; Güngör, Müzeyyen Nazli
2017-01-01
This study investigates the 3rd year and 4th year pre-service teachers' evaluations of the practices in teaching English to young learners in terms of 21st century teacher qualifications. Employing a mixed methods design, this study includes the qualitative data that come from semi-structured interviewed questions administered to pre-service…
ERIC Educational Resources Information Center
Amimo, Catherine Adhiambo
2016-01-01
This study investigated management of change in teacher education curriculum in Private universities in Kenya. The study employed a concurrent mixed methods design that is based on the use of both quantitative and qualitative approaches. A multi-stage sampling process which included purposive, convenience, cluster, and snowball sampling methods…
Timming, Andrew R.; Re, Daniel; Perrett, David I.
2016-01-01
Using mixed design analysis of variance (ANOVA), this paper investigates the effects of a subtle simulated increase in adiposity on women’s employment chances in the service sector. Employing a unique simulation of altering individuals’ BMIs and the literature on “aesthetic labour”, the study suggests that, especially for women, being heavier, but still within a healthy BMI, deleteriously impacts on hireability ratings. The paper explores the gendered dimension of this prejudice by asking whether female employees at the upper end of a healthy BMI range are likely to be viewed more negatively than their overtly overweight male counterparts. The paper concludes by considering the implications of these findings. PMID:27603519
Lu, Tao; Lu, Minggen; Wang, Min; Zhang, Jun; Dong, Guang-Hui; Xu, Yong
2017-12-18
Longitudinal competing risks data frequently arise in clinical studies. Skewness and missingness are commonly observed for these data in practice. However, most joint models do not account for these data features. In this article, we propose partially linear mixed-effects joint models to analyze skew longitudinal competing risks data with missingness. In particular, to account for skewness, we replace the commonly assumed symmetric distributions by asymmetric distribution for model errors. To deal with missingness, we employ an informative missing data model. The joint models that couple the partially linear mixed-effects model for the longitudinal process, the cause-specific proportional hazard model for competing risks process and missing data process are developed. To estimate the parameters in the joint models, we propose a fully Bayesian approach based on the joint likelihood. To illustrate the proposed model and method, we implement them to an AIDS clinical study. Some interesting findings are reported. We also conduct simulation studies to validate the proposed method.
ERIC Educational Resources Information Center
Lane, Thomas H.
1981-01-01
Discusses a U.S. Supreme Court decision involving public employers'"mixed motives" in discharging employees for constitutionally protected and unprotected reasons. Describes the Court's test to distinguish which reason was the dominant factor. (RW)
Online capacitive densitometer
Porges, K.G.
1988-01-21
This invention is an apparatus for measuring fluid density of mixed phase fluid flow. The apparatus employs capacitive sensing of the mixed phased flow combined with means for uniformizing the electric field between the capacitor plates to account for flow line geometry. From measurement of fluid density, the solids feedrate can be ascertained. 7 figs.
Online capacitive densitometer
Porges, Karl G.
1990-01-01
This invention is an apparatus for measuring fluid density of mixed phase fluid flow. The apparatus employs capacitive sensing of the mixed phased flow combined with means for uniformizing the electric field between the capacitor plates to account for flow line geometry. From measurement of fluid density, the solids feedrate can be ascertained.
Optimization of instant dalia dessert pre-mix production by using response surface methodology.
Jha, Alok; Shalini, B N; Patel, Ashok Ambalal; Singh, Mithilesh; Rasane, Prasad
2015-02-01
Dalia, a wheat-based, particulate containing dairy dessert is popularly consumed as a breakfast food and is also considered as a health food. Though popular throughout Northern parts of the country, its limited shelf-life even under refrigeration imposes severe restrictions on its organized manufacture and marketing. In order to promote dalia dessert as a marketable product, in the present study, a process was developed for manufacture of instant dalia pre-mix, as a dry product with long shelf-life, which could be attractively packaged and easily reconstituted for consumption. During the investigation, the effect of different levels of milk solids and wheat solids was studied on dalia pre-mix quality by employing a central composite rotatable design (CCRD). The suggested formulation had 17.82 % milk solids and 2.87 % wheat solids. This formulation was found to be most appropriate for manufacture of instant dalia pre-mix with predicted sensory scores (Max. 100) of 85.35, 41.98 and 67.27 for mouthfeel, consistency and flavor, respectively; the viscosity of the product was 941.0 cp.
2015-01-01
The present study tested our hypothesis that university students with irritable bowel syndrome (IBS) may experience less satisfactory academic lives than those of students without IBS. We also verified the hypothesis that university students with IBS might have higher employment anxiety than students without IBS might. We conducted a cross-sectional study of 1,686 university students. Presence or absence of IBS was assessed via the Rome III Questionnaire. Two original items were used to evaluate academic life. The prevalence rates of IBS with diarrhea, IBS with constipation, mixed IBS, and unsubtyped IBS in the study population were 5%, 2%, 10%, and 3%, respectively. Regarding academic life, the proportions of participants who experienced maladjustment and employment anxiety were 29% and 50%, respectively. After adjusting for age, sex, and faculty, the odds ratios for maladjustment and employment anxiety were significantly higher in students who screened positively, relative to those who screened negatively, for IBS (OR, 1.62; 95% CI, 1.24–2.21; OR, 2.16; 95% CI, 1.68–2.81, respectively). In conclusion, maladjustment and anxiety over future employment were higher in university students with IBS relative to those without. PMID:26083662
Tayama, Jun; Nakaya, Naoki; Hamaguchi, Toyohiro; Saigo, Tatsuo; Takeoka, Atsushi; Sone, Toshimasa; Fukudo, Shin; Shirabe, Susumu
2015-01-01
The present study tested our hypothesis that university students with irritable bowel syndrome (IBS) may experience less satisfactory academic lives than those of students without IBS. We also verified the hypothesis that university students with IBS might have higher employment anxiety than students without IBS might. We conducted a cross-sectional study of 1,686 university students. Presence or absence of IBS was assessed via the Rome III Questionnaire. Two original items were used to evaluate academic life. The prevalence rates of IBS with diarrhea, IBS with constipation, mixed IBS, and unsubtyped IBS in the study population were 5%, 2%, 10%, and 3%, respectively. Regarding academic life, the proportions of participants who experienced maladjustment and employment anxiety were 29% and 50%, respectively. After adjusting for age, sex, and faculty, the odds ratios for maladjustment and employment anxiety were significantly higher in students who screened positively, relative to those who screened negatively, for IBS (OR, 1.62; 95% CI, 1.24-2.21; OR, 2.16; 95% CI, 1.68-2.81, respectively). In conclusion, maladjustment and anxiety over future employment were higher in university students with IBS relative to those without.
NASA Technical Reports Server (NTRS)
Newman, P. A.; Schoeberl, M. R.; Plumb, R. A.
1986-01-01
Calculations of the two-dimensional, species-independent mixing coefficients for two-dimensional chemical models for the troposphere and stratosphere are performed using quasi-geostrophic potential vorticity fluxes and gradients from 4 years of National Meteorological Center data for the four seasons in both hemispheres. Results show that the horizontal mixing coefficient values for the winter lower stratosphere are broadly consistent with those currently employed in two-dimensional models, but the horizontal mixing coefficient values in the northern winter upper stratosphere are much larger than those usually used.
[Marketing mix in health service].
Ameri, Cinzia; Fiorini, Fulvio
2015-01-01
The marketing mix is the combination of the marketing variables that a firm employs with the purpose to achieve the expected volume of business within its market. In the sale of goods, four variables compose the marketing mix (4 Ps): Product, Price, Point of sale and Promotion. In the case of providing services, three further elements play a role: Personnel, Physical Evidence and Processes (7 Ps). The marketing mix must be addressed to the consumers as well as to the employees of the providing firm. Furthermore, it must be interpreted as employees ability to satisfy customers (interactive marketing).
NASA Astrophysics Data System (ADS)
Cai, Zun; Liu, Xiao; Gong, Cheng; Sun, Mingbo; Wang, Zhenguo; Bai, Xue-Song
2016-09-01
Large Eddy Simulation (LES) was employed to investigate the fuel/oxidizer mixing process in an ethylene fueled scramjet combustor with a rearwall-expansion cavity. The numerical solver was first validated for an experimental flow, the DLR strut-based scramjet combustor case. Shock wave structures and wall-pressure distribution from the numerical simulations were compared with experimental data and the numerical results were shown in good agreement with the available experimental data. Effects of the injection location on the flow and mixing process were then studied. It was found that with a long injection distance upstream the cavity, the fuel is transported much further into the main flow and a smaller subsonic zone is formed inside the cavity. Conversely, with a short injection distance, the fuel is entrained more into the cavity and a larger subsonic zone is formed inside the cavity, which is favorable for ignition in the cavity. For the rearwall-expansion cavity, it is suggested that the optimized ignition location with a long upstream injection distance should be in the bottom wall in the middle part of the cavity, while the optimized ignition location with a short upstream injection distance should be in the bottom wall in the front side of the cavity. By employing a cavity direct injection on the rear wall, the fuel mass fraction inside the cavity and the local turbulent intensity will both be increased due to this fueling, and it will also enhance the mixing process which will also lead to increased mixing efficiency. For the rearwall-expansion cavity, the combined injection scheme is expected to be an optimized injection scheme.
Brown, Judith; Neary, Joanne; Katikireddi, Srinivasa Vittal; Thomson, Hilary; McQuaid, Ronald W; Leyland, Alastair H; Frank, John; Jeavons, Luke; de Pellette, Paul; Kiran, Sibel; Macdonald, Ewan B
2015-01-01
Introduction Increasing employment among older workers is a policy priority given the increase in life expectancy and the drop in labour force participation after the age of 50. Reasons for this drop are complex but include poor health, age discrimination, inadequate skills/qualifications and caring roles; however, limited evidence exists on how best to support this group back to work. The Work Programme is the UK Government's flagship policy to facilitate return to work (RTW) among those at risk of long-term unemployment. ‘Supporting Older People Into Employment’ (SOPIE) is a mixed-methods longitudinal study involving a collaboration between academics and a major Work Programme provider (Ingeus). The study will investigate the relationship between health, worklessness and the RTW process for the over 50s. Methods and analysis There are three main study components. Embedded fieldwork will document the data routinely collected by Ingeus and the key interventions/activities delivered. The quantitative study investigates approximately 14 000 individuals (aged 16–64 years, with 20% aged over 50) who entered the Ingeus Work Programme (referred to as ‘clients’) in a 16-month period in Scotland and were followed up for 2 years. Employment outcomes (including progression towards work) and how they differ by client characteristics (including health), intervention components received and external factors will be investigated. The qualitative component will explore the experiences of clients and Ingeus staff, to better understand the interactions between health and (un)employment, Work Programme delivery, and how employment services can be better tailored to the needs of the over 50s. Ethics and dissemination Ethical approval was received from the University of Glasgow College of Social Sciences Research Ethics Committee (application number 400140186). Results Results will be disseminated through journal articles, national and international conferences. Findings will inform current and future welfare-to-work and job retention initiatives to extend healthy working lives. PMID:26674507
Cognitive hypnotherapy with bulimia.
Barabasz, Marianne
2012-04-01
Research on the efficacy of hypnosis in the treatment of bulimia nervosa has produced mixed findings. This is due in part to the interplay between the characteristics of people with bulimia and the wide variety of hypnosis interventions that have been employed. Several authors have noted that methodological limitations in hypnosis research often make evaluation of treatment efficacy difficult. Many of the studies extant provide insufficient information regarding the specifics of participants' hypnotizability, the hypnotic induction, or the hypnotic suggestion(s) employed. Such limitations preclude replication and clinical implementation. This article reviews the literature with replicable methodologies and discusses the implications for evaluating treatment efficacy.
Process-model simulations of cloud albedo enhancement by aerosols in the Arctic.
Kravitz, Ben; Wang, Hailong; Rasch, Philip J; Morrison, Hugh; Solomon, Amy B
2014-12-28
A cloud-resolving model is used to simulate the effectiveness of Arctic marine cloud brightening via injection of cloud condensation nuclei (CCN), either through geoengineering or other increased sources of Arctic aerosols. An updated cloud microphysical scheme is employed, with prognostic CCN and cloud particle numbers in both liquid and mixed-phase marine low clouds. Injection of CCN into the marine boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. Albedo increases are stronger for pure liquid clouds than mixed-phase clouds. Liquid precipitation can be suppressed by CCN injection, whereas ice precipitation (snow) is affected less; thus, the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. CCN injection into a clean regime results in a greater albedo increase than injection into a polluted regime, consistent with current knowledge about aerosol-cloud interactions. Unlike previous studies investigating warm clouds, dynamical changes in circulation owing to precipitation changes are small. According to these results, which are dependent upon the representation of ice nucleation processes in the employed microphysical scheme, Arctic geoengineering is unlikely to be effective as the sole means of altering the global radiation budget but could have substantial local radiative effects. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Process-model simulations of cloud albedo enhancement by aerosols in the Arctic
Kravitz, Ben; Wang, Hailong; Rasch, Philip J.; Morrison, Hugh; Solomon, Amy B.
2014-01-01
A cloud-resolving model is used to simulate the effectiveness of Arctic marine cloud brightening via injection of cloud condensation nuclei (CCN), either through geoengineering or other increased sources of Arctic aerosols. An updated cloud microphysical scheme is employed, with prognostic CCN and cloud particle numbers in both liquid and mixed-phase marine low clouds. Injection of CCN into the marine boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. Albedo increases are stronger for pure liquid clouds than mixed-phase clouds. Liquid precipitation can be suppressed by CCN injection, whereas ice precipitation (snow) is affected less; thus, the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. CCN injection into a clean regime results in a greater albedo increase than injection into a polluted regime, consistent with current knowledge about aerosol–cloud interactions. Unlike previous studies investigating warm clouds, dynamical changes in circulation owing to precipitation changes are small. According to these results, which are dependent upon the representation of ice nucleation processes in the employed microphysical scheme, Arctic geoengineering is unlikely to be effective as the sole means of altering the global radiation budget but could have substantial local radiative effects. PMID:25404677
ERIC Educational Resources Information Center
Soebari, Titien; Aldridge, Jill M.
2016-01-01
This article reports on the differential effectiveness of a teacher professional development programme for teachers in urban and rural schools in Indonesia. The study employed an embedded mixed methods design that involved the concurrent collection of both quantitative and qualitative data. The quantitative component involved a pre-post design in…
ERIC Educational Resources Information Center
Stollar, Lori J.
2014-01-01
This study of a suburban school district in south central Pennsylvania employed a mixed method design to explore teachers' perceptions of their professional learning community (PLC) and the impact of such on teaching effectiveness and student learning. Perceptual data was collected through the Learning Community Culture Indicator (LCCI) teacher…
ERIC Educational Resources Information Center
Chen, Ying-Chih; Hand, Brian; Park, Soonhye
2016-01-01
Argumentation, and the production of scientific arguments are critical elements of inquiry that are necessary for helping students become scientifically literate through engaging them in constructing and critiquing ideas. This case study employed a mixed methods research design to examine the development in 5th grade students' practices of oral…
ERIC Educational Resources Information Center
Ho, Hsuan-Fu; Hung, Chia-Chi
2008-01-01
Purpose: The purpose of this paper is to examine how a graduate institute at National Chiayi University (NCYU), by using a model that integrates analytic hierarchy process, cluster analysis and correspondence analysis, can develop effective marketing strategies. Design/methodology/approach: This is primarily a quantitative study aimed at…
Learning Patterns in Music Practice: Links between Disposition, Practice Strategies and Outcomes
ERIC Educational Resources Information Center
StGeorge, Jennifer Mary; Holbrook, Allyson Patricia; Cantwell, Robert H.
2012-01-01
Research into musical practice has over recent decades focused on the technical and organisational strategies employed by novices and experts. What has been less studied are the background factors or influences on the quality of this music practice. Drawing on interview data collected from 66 children and adults from a mixed methods project, we…
ERIC Educational Resources Information Center
Weissman, Evan
2015-01-01
Driven by social and environmental criticism of the neoliberalization of agro-food systems, urban agriculture today enjoys renewed interest throughout the United States as a primary space to engage the politics of food. Using Brooklyn, New York as a case study, I employ mixed qualitative methods to investigate the contradictions that arise in…
Qualifying the Workforce: The Use of Nationally-Recognised Training in Australian Companies
ERIC Educational Resources Information Center
Smith, Erica; Smith, Andrew; Pickersgill, Richard; Rushbrook, Peter
2006-01-01
Purpose: To report on research that examines the impact of the adoption of nationally-recognised training by enterprises in Australia. Design/methodology/approach: The project involved a mix of methodologies including focus groups, employer survey and case studies. Findings: The research found that there had been a higher than expected adoption of…
ERIC Educational Resources Information Center
Gann, Linda
2013-01-01
The research centered on secondary mathematics teachers' beliefs, attitudes, knowledge base, and practices in meeting the academic and language needs of English language learners. Using socio-cultural theory and social practice theory to frame the study, the research design employed a mixed methods approach incorporating self-reported surveys,…
A Mixed Methods Analysis of a Single-Course Strategy to Integrate Technology into PETE
ERIC Educational Resources Information Center
Wyant, James D.; Jones, Emily M.; Bulger, Sean M.
2015-01-01
In recent years increased attention has been placed on physical education teachers' use of technology. To date little research has been disseminated regarding the strategies physical education teacher education (PETE) programs are employing to prepare preservice teacher's to use technology. The purpose of this study was to examine the influence a…
Influence of Parental Education and Family Income on Children's Education in Rural Uganda
ERIC Educational Resources Information Center
Drajea, Alice J.; O'Sullivan, Carmel
2014-01-01
This article investigates the effect of parents' literacy levels and family income in Uganda on the quality and nature of parents' involvement in their children's primary education. A mixed-methods study with an ethnographic element was employed to explore the views and opinions of 21 participants through a qualitative approach. Methods for data…
Pupils' Views of Religious Education in a Pluralistic Educational Context
ERIC Educational Resources Information Center
Kuusisto, Arniika; Kallioniemi, Arto
2014-01-01
This article examines Finnish pupils' views of religious education (RE) in a pluralistic educational context. The focus is on pupils' views of the aims and different approaches to RE in a multi-faith school. The study utilised a mixed method approach, combining quantitative and qualitative data. It employed a survey (n = 1301) and interviews (n =…
ERIC Educational Resources Information Center
Mayer, Anysia P.
2008-01-01
Students of color are consistently underrepresented in honors and gifted programs nationwide, and even high-achieving students share many of the risk factors with their low-achieving peers. The study presented in this paper employed mixed methods to investigate the relationship between the design of a rigorous college preparatory program, the…
ERIC Educational Resources Information Center
Swan, Karen; Van 'T Hooft, Mark; Kratcoski, Annette; Schenker, Jason
2007-01-01
This article reports on preliminary findings from an ongoing study of teaching and learning in a ubiquitous computing classroom. The research employed mixed methods and multiple measures to document changes in teaching and learning that result when teachers and students have access to a variety of digital devices wherever and whenever they need…
ERIC Educational Resources Information Center
Best, Linda M.; Shelley, Daniel J.
2018-01-01
This article examines the effects of the social media applications Facebook, Twitter, Snap Chat/Instagram, Texting and various smartphone applications on academic dishonesty in higher education. The study employed a mixed-methods approach conducted through an emailed question-pro student survey consisting of 20 questions. The results of the study…
The Career Counseling Needs of Mothers in the Criminal Justice System
ERIC Educational Resources Information Center
Laux, John M.; Calmes, Stephanie; Moe, Jeffry L.; Dupuy, Paula J.; Cox, Jane A.; Ventura, Lois A.; Williamson, Celia; Benjamin, Barbaranne J.; Lambert, Eric
2011-01-01
The past 2 decades have produced a rapid increase in the numbers of incarcerated mothers. This study investigated both career development and the career counseling needs of mothers in the criminal justice system. A mixed-methods design was employed using both qualitative interviews (n = 1,161) and quantitative survey methods (n = 1,170).…
ERIC Educational Resources Information Center
Digelidis, Nikolaos; Karageorghis, Costas I.; Papapavlou, Anastasia; Papaioannou, Athanasios G.
2014-01-01
The aim of this study was to examine the effects of asynchronous (background) music on senior students' motivation and lesson satisfaction at the situational level. A counterbalanced mixed-model design was employed with two factors comprising condition (three levels) and gender (two levels). Two hundred students (82 boys, 118 girls; M [subscript…
ERIC Educational Resources Information Center
Chu, Yu-Kuang; Nishimoto, Koji
1969-01-01
Chinese and Japanese, although they are unrelated languages, nevertheless have similar writing systems, since Japanese writing employs a mixed system of Chinese characters and phonetic script. Because Chinese characters are difficult to learn, however, reform movements to simplify the writing system to make the task of learning easier for a…
ERIC Educational Resources Information Center
Wynants, Shelli A.; Dennis, Jessica M.
2017-01-01
Despite the critical role that faculty play in the success of students with disabilities in higher education, professional development for promoting the understanding of these students' needs and the employment of inclusive instructional strategies to enhance their success has been limited. To better assess the potential of the online environment…
ERIC Educational Resources Information Center
Shannonhouse, Laura; Myers, Jane; Barden, Sejal; Clarke, Philip; Weimann, Rochelle; Forti, Allison; Moore-Painter, Terry; Knutson, Tami; Porter, Michael
2014-01-01
Group interventions have been useful for survivors to overcome the challenges of cancer. This study employed a pre/post, mixed-methods design to explore the influence of an 8-week support group on the holistic wellness of 14 breast cancer survivors. Pairing experiential activities with wellness-centered psychoeducation was viewed positively by…
ERIC Educational Resources Information Center
Thompson, Leanne J.; Clark, Gordon; Walker, Marion; Whyatt, J. Duncan
2013-01-01
Students' experience of higher education comprises not only their academic studies but also their extracurricular activities. This article reports on the findings from a mixed-methods research project, exploring in detail the nature and value of extracurricular activity engagement and the significance of institutional schemes encouraging…
Teachers Helping Teachers: A Professional Development Model That Promotes Teacher Leadership
ERIC Educational Resources Information Center
Ghamrawi, Norma
2013-01-01
This mixed methods study reports on the outcomes of a professional development model (PDM) developed by a K-12 private school in Beirut, Lebanon, after 3 years of its employment. Specifically, an evaluation of this PDM is provided with special emphasis on its potential of developing teacher leaders at school. The PDM embraces a constructivist…
Brief Report: Reduced Prioritization of Facial Threat in Adults with Autism
ERIC Educational Resources Information Center
Sasson, Noah J.; Shasteen, Jonathon R.; Pinkham, Amy E.
2016-01-01
Typically-developing (TD) adults detect angry faces more efficiently within a crowd than non-threatening faces. Prior studies of this social threat superiority effect (TSE) in ASD using tasks consisting of schematic faces and homogeneous crowds have produced mixed results. Here, we employ a more ecologically-valid test of the social TSE and find…
ERIC Educational Resources Information Center
Howard, Chris; Davies, Peter
2013-01-01
This paper reports on data collected during an evaluation of two higher education courses designed to attract mature entrants aged between 21 and 60 to undergraduate degree programmes. Employing an evaluation design informed by a critical realist approach, the study utilised a mix of quantitative and qualitative methods to investigate the outcomes…
[Health risk among workers employed in rubber footwear plant].
Szubert, Z; Wilczyńska, U; Sobala, W
2001-01-01
The aim of the study was to assess the health risk of workers performing specific jobs in the process of the rubber footwear production by defining the cause and length of temporary work disability, as well as mortality causes and level. The analysis was carried out in the groups of workers performing the following jobs: mixing, mill operation, pressing and vulcanizing (A); semi-product preparation and calendaring (B); finishing and sorting (C); production of polyvinyl chloride footwear (D); and auxiliary works (E). The sickness absence study covered all workers (208 men and 315 women) employed in a large rubber footwear company and performing all above-listed jobs in 1995. Standardized sick days ratio was used to analyze the risk of temporary work disability. Mortality rate was estimated on the basis of the results of the cohort study performed in the same company among workers who had worked at least three months during the years 1945-1985. The follow-up continued until 31 December 1997. The present study included sub-cohorts composed of 5628 men and 7197 women, performing jobs listed above. The results of both studies indicated the enhanced risk of cardiovascular diseases among workers employed in the basic phases of the production process. The increased risk of the diseases of the digestive system was observed in men and women employed in: finishing, sorting and packing of the products (group C); in men involved in mixing, pressing and vulcanizing (group A); and in women engaged in auxiliary works (group E). In addition, the enhanced risk of sickness absence due to the diseases of the respiratory, digestive, or genitourinary systems was related to the enhanced risk of death from malignant neoplasms in a given site. The analysis showed that the temporary work disability may be regarded as a parameter useful in early assessment of health effects of the work environmental hazards.
Neubert, Lydia; König, Hans-Helmut; Brettschneider, Christian
2018-02-27
The debate on reconciliation between childcare and working has to be expanded to caregiving for the elderly, since the importance of informal caregiving will increase in the future due to populations' ageing and women's increasing labour force participation. Informal caregivers who are caring for the rising number of persons with dementia (PwD) are often female and subjected to high caregiving requirements. These are added to further demands emerging from their family and work life. How affected caregivers seek to balance those requirements depends on, inter alia, their own characteristics and the informal caregiving network to whom they relate. Both aspects were not yet considered in previous studies. This mixed methods study thus aims to explore the reconciliation between caregiving in dementia, family and employment by including different members of caregiving networks of home-dwelling PwD and by considering their personal characteristics. By purposive sampling, we include at least five caregiving networks of home-dwelling PwD; each of them consisting of at least three informal caregivers living in Northern Germany. Narrative interviews of participants will be recorded, transcribed verbatim and interpreted according to the Documentary Method (QUAL). By completing standardised questionnaires, participants will provide sociodemographic and psychographic data concerning themselves and the networks from whom they arise (quan). This supplemental, descriptive information will give further background to the themes and types emerging from the interviews. Hence, the quan-data enrich the QUAL-data by exploring the narratives of participants in the light of their personal and network-related characteristics. Ethical approval was obtained from the Ethics Committee of the German Society of Nursing Sciences. Study results will be disseminated through conference presentations and publications in peer-reviewed journals. DRKS00012929. © 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.
Chatterji, Pinka; Alegria, Margarita; Lu, Mingshan; Takeuchi, David
2009-01-01
This paper investigates to what extent psychiatric disorders and mental distress affect labor market outcomes in two rapidly growing populations that have not been studied to date – ethnic minorities of Latino and Asian descent, most of whom are immigrants. Using data from the National Latino and Asian American Study (NLAAS), we examine the labor market effects of having any psychiatric disorder in the past 12 months as well as the effects of experiencing psychiatric distress in the past 12 months. The labor market outcomes analyzed are current employment status, the number of weeks worked in the past year among those who are employed, and having at least one work absence in the past month among those who are employed. Our results show that among Latinos, psychiatric disorders and mental distress are associated with large, detrimental effects on employment and absenteeism, similar to effects found in analyses of mostly white, American born populations. Among Asians, we find more mixed evidence that psychiatric disorders and mental distress detract from labor market outcomes. PMID:17294497
Particle cloud mixing in microgravity
NASA Technical Reports Server (NTRS)
Ross, H.; Facca, L.; Tangirala, V.; Berlad, A. L.
1989-01-01
Quasi-steady flame propagation through clouds of combustible particles requires quasi-steady transport properties and quasi-steady particle number density. Microgravity conditions may be employed to help achieve the conditions of quiescent, uniform clouds needed for such combustion studies. Joint experimental and theoretical NASA-UCSD studies were concerned with the use of acoustic, electrostatic, and other methods of dispersion of fuel particulates. Results of these studies are presented for particle clouds in long cylindrical tubes.
Kwak, Lydia; Berrigan, David; Van Domelen, Dane; Sjöström, Michael; Hagströmer, Maria
2016-06-01
The aim of the study was to examine the relationship between employment status and job activity level with physical activity (PA) and sedentary time, stratified by gender and country. Cross-sectional study design. Data from working age adults (18-65 years) from two cross-sectional studies, the Swedish 2001-2002 and 2007-2008 Attitude Behavior and Change Study (ABC; n=1165) and the 2003-2006 US National Health and Nutrition Examination Survey (NHANES; n=4201), were stratified by employment status (employed and not employed) and job activity level (active, sedentary and mixed). PA in counts×min(-1) and time spent in sedentary, low and moderate or higher intensity were measured with accelerometers. Analyses were conducted in 2012-2013. In NHANES, the employed had significantly higher counts×min(-1) and spent more time in moderate or higher intensity PA than those not employed. In ABC, no significant differences were observed between employed and unemployed. Adults with active versus sedentary occupations had higher counts×min(-1) and less sedentary time in both the USA and Sweden and in both men and women. For example, counts×min(-1) were 20-40% greater in active versus sedentary jobs. Employment status is related to PA and sedentary time among men and women in the USA but not in Sweden. Among the employed, occupational PA is associated with total PA and sedentary time for both genders and in both countries. Comparisons of PA levels based on objective measurements can refine understanding of country differences in activity. Copyright © 2015 Sports Medicine Australia. All rights reserved.
Michalchuk, Adam A L; Hope, Karl S; Kennedy, Stuart R; Blanco, Maria V; Boldyreva, Elena V; Pulham, Colin R
2018-04-17
Resonant acoustic mixing (RAM) is a new technology designed for intensive mixing of powders that offers the capability to process powders with minimal damage to particles. This feature is particularly important for mixing impact-sensitive materials such as explosives and propellants. While the RAM technique has been extensively employed for the mixing of powders and viscous polymers, comparatively little is known about its use for mechanosynthesis. We present here the first in situ study of RAM-induced co-crystallisation monitored using synchrotron X-ray powder diffraction. The phase profile of the reaction between nicotinamide and carbamazepine in the presence of a small amount of water was monitored at two different relative accelerations of the mixer. In marked contrast to ball-milling techniques, the lack of milling bodies in the RAM experiment does not hinder co-crystallisation of the two starting materials, which occurred readily and was independent of the frequency of oscillation. The reaction could be optimised by enhancing the number of reactive contacts through mixing and comminution. These observations provide new insight into the role of various experimental parameters in conventional mechanochemistry using liquid-assisted grinding techniques.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prasankumar, T.; Jose, Sujin P., E-mail: sujamystica@yahoo.com; Ilangovan, R.
Nanostructured Mn/Ni mixed metal oxide was synthesized at ambient temperature by facile microwave irradiation technique. The crystal structure and surface morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. X-ray diffraction analysis confirmed the formation of Mn/Ni mixed oxide in rhombohedral phase and the grain size calculated was found to be 87 nm. The irregular spherical morphology of the prepared sample was exhibited by the SEM images. The characteristic peaks of FTIR at about 630 cm{sup −1} and 749 cm{sup −1} were attributed to the Mn-O and Ni-O stretching vibrations respectively. The presence of both Mn and Ni inmore » the prepared sample was validated by the EDS spectra which in turn confirmed the formation of mixed oxide. Cyclic voltammetry and galvanostatic chargedischarge measurements were employed to investigate the electrochemical performance of the mixed oxide. The cyclic voltammetry curves demonstrated good capacitive performance of the sample in the potential window −0.2V to 0.9V. The charge discharge study revealed the suitability of the prepared mixed oxide for the fabrication of supercapacitor electrode.« less
Kaneko, Masato; Tanigawa, Takahiko; Hashizume, Kensei; Kajikawa, Mariko; Tajiri, Masahiro; Mueck, Wolfgang
2013-01-01
This study was designed to confirm the appropriateness of the dose setting for a Japanese phase III study of rivaroxaban in patients with non-valvular atrial fibrillation (NVAF), which had been based on model simulation employing phase II study data. The previously developed mixed-effects pharmacokinetic/pharmacodynamic (PK-PD) model, which consisted of an oral one-compartment model parameterized in terms of clearance, volume and a first-order absorption rate, was rebuilt and optimized using the data for 597 subjects from the Japanese phase III study, J-ROCKET AF. A mixed-effects modeling technique in NONMEM was used to quantify both unexplained inter-individual variability and inter-occasion variability, which are random effect parameters. The final PK and PK-PD models were evaluated to identify influential covariates. The empirical Bayes estimates of AUC and C(max) from the final PK model were consistent with the simulated results from the Japanese phase II study. There was no clear relationship between individual estimated exposures and safety-related events, and the estimated exposure levels were consistent with the global phase III data. Therefore, it was concluded that the dose selected for the phase III study with Japanese NVAF patients by means of model simulation employing phase II study data had been appropriate from the PK-PD perspective.
Optimum survey methods when interviewing employed women.
Dunning, Kari; LeMasters, Grace K
2009-02-01
While survey studies have examined bias much is unknown regarding specific subpopulations, especially women workers. A population based phone, Internet, and mail survey of workplace falls during pregnancy was undertaken. Participation by industry and occupation and survey approach and bias, reliability, and incomplete data were examined. Of the 3,997 women surveyed, 71% were employed during their pregnancy. Internet responders were most likely to be employed while pregnant and to report a workplace fall at 8.8% compared to 5.8% and 6.1% for mail and phone respondents. Internet responders had the most missing employment data with company name missing for 17.9% compared to 1.3% for phone responders. Mail surveys were best for recruiting those employed in eight of nine industries, and this was especially true for service occupations. To decrease bias and increase participation, mixed approaches may be useful with particular attention for collecting occupational data. Am. J. Ind. Med. 52:105-112, 2009. (c) 2008 Wiley-Liss, Inc.
ERIC Educational Resources Information Center
Esongo, Njie Martin
2017-01-01
The study takes an in-depth examination of the extent to which the availability of resources relates to the efficiency of the school system within the framework of the implementation of competency-based teaching approaches in Cameroon. The study employed a mix of probability sampling approaches, namely simple, cluster and stratified random…
ERIC Educational Resources Information Center
Zhang, Haisen; Song, Wei; Shen, Suping; Huang, Ronghuai
2014-01-01
This paper reported on a study of using blogs as out-of-class assignments for the development of learners' writing competence. There were 36 students of English majors from an intact second language (L2) writing class participating in this study. A mixed method design was employed to obtain both quantitative and qualitative data. The results…
Jet mixing in low gravity - Results of the Tank Pressure Control Experiment
NASA Technical Reports Server (NTRS)
Bentz, M. D.; Meserole, J. S.; Knoll, R. H.
1992-01-01
The Tank Pressure Control Experiment (TPCE) is discussed with attention given to the results for controlling storage-tank pressures by forced-convective mixing in microgravitational environments. The fluid dynamics of cryogenic fluids in space is simulated with freon-113 during axial-jet-induced mixing. The experimental flow-pattern data are found to confirm previous data as well as existing mixing correlations. Thermal nonuniformities and tank pressure can be reduced by employing low-energy mixing jets which are useful for enhancing heat/mass transfer between phases. It is found that space cryogenic systems based on the principle of active mixing can be more reliable and predictable than other methods, and continuous or periodic mixing can be accomplished with only minor energy addition to the fluid.
Soffer, Michal; Rimmerman, Arie
2012-06-01
This feasibility study examines the coverage of employment-related issues related to people with disabilities in the Americans with Disabilities Act of 1990. The study is a first in a series of future studies focusing on disability issues in the international economic media. A survey of 39 newspaper articles published in the Wall Street Journal, a leading and most circulated business newspaper in the USA. Specifically, it comprised articles taken from three periods: 1990, the year the Americans with Disabilities Act was enacted; 2000, a decade later; and 2008, the year the amendments were revised with respect to definitions and employment. Data were analyzed by quantitative and qualitative content analysis. The results suggest a mixed representation: a decline in negative representations of disability throughout the years alongside the emergence of a legal-fiscal discourse of a disability that depicts persons with disabilities as a fiscal burden on employers. It seems that the new image of disability presents conflicting interests between the mission of the law, promoting employers' hiring of people with disabilities, and the economic realities of accommodating them at the workplace. Additional research is needed to examine whether this image is unique to the economic media or may reflect a concern in the business community.
NASA Technical Reports Server (NTRS)
Liu, Nan-Suey; Shih, Tsan-Hsing; Wey, C. Thomas
2011-01-01
A series of numerical simulations of Jet-A spray reacting flow in a single-element lean direct injection (LDI) combustor have been conducted by using the National Combustion Code (NCC). The simulations have been carried out using the time filtered Navier-Stokes (TFNS) approach ranging from the steady Reynolds-averaged Navier-Stokes (RANS), unsteady RANS (URANS), to the dynamic flow structure simulation (DFS). The sub-grid model employed for turbulent mixing and combustion includes the well-mixed model, the linear eddy mixing (LEM) model, and the filtered mass density function (FDF/PDF) model. The starting condition of the injected liquid spray is specified via empirical droplet size correlation, and a five-species single-step global reduced mechanism is employed for fuel chemistry. All the calculations use the same grid whose resolution is of the RANS type. Comparisons of results from various models are presented.
Methods for the continuous production of plastic scintillator materials
Bross, Alan; Pla-Dalmau, Anna; Mellott, Kerry
1999-10-19
Methods for producing plastic scintillating material employing either two major steps (tumble-mix) or a single major step (inline-coloring or inline-doping). Using the two step method, the polymer pellets are mixed with silicone oil, and the mixture is then tumble mixed with the dopants necessary to yield the proper response from the scintillator material. The mixture is then placed in a compounder and compounded in an inert gas atmosphere. The resultant scintillator material is then extruded and pelletized or formed. When only a single step is employed, the polymer pellets and dopants are metered into an inline-coloring extruding system. The mixture is then processed under a inert gas atmosphere, usually argon or nitrogen, to form plastic scintillator material in the form of either scintillator pellets, for subsequent processing, or as material in the direct formation of the final scintillator shape or form.
Nanoporous Substrate with Mixed Nanoclusters for Surface Enhanced Raman Scattering.
NASA Astrophysics Data System (ADS)
Chang, Sehoon; Ko, Hyunhyub; Singamaneni, Srikanth; Gunawidjaja, Ray; Tsukruk, Vladimir
2009-03-01
Rapid detection of plastic and liquid explosives is an urgent need due to various societal and technological reasons. We employed a novel design of surface enhanced Raman scattering (SERS)-active substrate based on porous alumina membranes decorated with mixed nanoclusters of gold nanorods and nanoparticles. We demonstrated trace level detection of several important explosives such as dinitrotolene (DNT), trinitrotoluene (TNT), and hexamethylenetriperoxidediamine (HMTD) by fast, sensitive, reliable Raman spectroscopic method. We achieved near molecular-level detection (about 15˜ 30 molecules) of DNT and TNT utilizing the SERS substrate. However, trace level detection is challenging due to the lack of common optical signatures (fluorescence, absorption in UV-vis range) or chemical functionality of peroxide-based explosives such as HMTD. To overcome this, we employed photochemical decomposition approach and analyzed chemical fragments using SERS. We suggest that tailored polymer coating, mixed nanoclusters, and laser-induced photocatalytic decomposition are all critical for achieving this unprecedented sensitivity level..
Some possibilities of using gas mixtures other than air in aerodynamic research
NASA Technical Reports Server (NTRS)
Chapman, Dean R
1956-01-01
A study is made of the advantages that can be realized in compressible-flow research by employing a substitute heavy gas in place of air. The present report is based on the idea that by properly mixing a heavy monatomic gas with a suitable heavy polyatomic gas, it is possible to obtain a heavy gas mixture which has the correct ratio of specific heats and which is nontoxic, nonflammable, thermally stable, chemically inert, and comprised of commercially available components. Calculations were made of wind-tunnel characteristics for 63 gas pairs comprising 21 different polyatomic gases properly mixed with each of three monatomic gases (argon, krypton, and zenon).
2017-05-25
37 Research Design ... research employed a mixed research methodology – quantitative with descriptive statistical analysis and qualitative with a thematic analysis approach...mixed research methodology – quantitative and qualitative, using interviews to collect the data. The interviews included demographic and open-ended
NASA Astrophysics Data System (ADS)
Abas, Norzaida; Daud, Zalina M.; Yusof, Fadhilah
2014-11-01
A stochastic rainfall model is presented for the generation of hourly rainfall data in an urban area in Malaysia. In view of the high temporal and spatial variability of rainfall within the tropical rain belt, the Spatial-Temporal Neyman-Scott Rectangular Pulse model was used. The model, which is governed by the Neyman-Scott process, employs a reasonable number of parameters to represent the physical attributes of rainfall. A common approach is to attach each attribute to a mathematical distribution. With respect to rain cell intensity, this study proposes the use of a mixed exponential distribution. The performance of the proposed model was compared to a model that employs the Weibull distribution. Hourly and daily rainfall data from four stations in the Damansara River basin in Malaysia were used as input to the models, and simulations of hourly series were performed for an independent site within the basin. The performance of the models was assessed based on how closely the statistical characteristics of the simulated series resembled the statistics of the observed series. The findings obtained based on graphical representation revealed that the statistical characteristics of the simulated series for both models compared reasonably well with the observed series. However, a further assessment using the AIC, BIC and RMSE showed that the proposed model yields better results. The results of this study indicate that for tropical climates, the proposed model, using a mixed exponential distribution, is the best choice for generation of synthetic data for ungauged sites or for sites with insufficient data within the limit of the fitted region.
NASA Astrophysics Data System (ADS)
Hadi, Fatemeh; Janbozorgi, Mohammad; Sheikhi, M. Reza H.; Metghalchi, Hameed
2016-10-01
The rate-controlled constrained-equilibrium (RCCE) method is employed to study the interactions between mixing and chemical reaction. Considering that mixing can influence the RCCE state, the key objective is to assess the accuracy and numerical performance of the method in simulations involving both reaction and mixing. The RCCE formulation includes rate equations for constraint potentials, density and temperature, which allows taking account of mixing alongside chemical reaction without splitting. The RCCE is a dimension reduction method for chemical kinetics based on thermodynamics laws. It describes the time evolution of reacting systems using a series of constrained-equilibrium states determined by RCCE constraints. The full chemical composition at each state is obtained by maximizing the entropy subject to the instantaneous values of the constraints. The RCCE is applied to a spatially homogeneous constant pressure partially stirred reactor (PaSR) involving methane combustion in oxygen. Simulations are carried out over a wide range of initial temperatures and equivalence ratios. The chemical kinetics, comprised of 29 species and 133 reaction steps, is represented by 12 RCCE constraints. The RCCE predictions are compared with those obtained by direct integration of the same kinetics, termed detailed kinetics model (DKM). The RCCE shows accurate prediction of combustion in PaSR with different mixing intensities. The method also demonstrates reduced numerical stiffness and overall computational cost compared to DKM.
NASA Astrophysics Data System (ADS)
Zhang, Li; Liao, Jian-Shang
2010-05-01
The interface-optical-propagating (IO-PR) mixing phonon modes of a quasi-zero-dimensional (QoD) wurtzite cylindrical quantum dot (QD) structure are derived and studied by employing the macroscopic dielectric continuum model. The analytical phonon states of IO-PR mixing modes are given. It is found that there are two types of IO-PR mixing phonon modes, i.e. ρ-IO/z-PR mixing modes and the z-IO/ρ-PR mixing modes existing in QoD wurtzite QDs. And each IO-PR mixing modes also have symmetrical and antisymmetrical forms. Via a standard procedure of field quantization, the Fröhlich Hamiltonians of electron-(IO-PR) mixing phonons interaction are obtained. Numerical calculations on a wurtzite GaN cylindrical QD are performed. The results reveal that both the radial-direction size and the axial-direction size as well as the dielectric matrix have great influence on the dispersive frequencies of the IO-PR mixing phonon modes. The limiting features of dispersive curves of these phonon modes are discussed in depth. The phonon modes “reducing" behavior of wurtzite quantum confined systems has been observed obviously in the structures. Moreover, the degenerating behaviors of the IO-PR mixing phonon modes in wurtzite QoD QDs to the IO modes and PR modes in wurtzite Q2D QW and Q1D QWR systems are analyzed deeply from both of the viewpoints of physics and mathematics.
Working with Persistent Pain: An Exploration of Strategies Utilised to Stay Productive at Work.
Oakman, Jodi; Kinsman, Natasha; Briggs, Andrew M
2017-03-01
Purpose Maintaining productive employment for people with persistent pain conditions is challenging. This study aims to explore supports-work and non-work- used by employees to assist them in maintaining productive employment. Methods An exploratory, mixed-methods study comprising a questionnaire battery followed by semi-structured interviews to collect in-depth qualitative data was undertaken. The questionnaires measured descriptive variables used to select participants for interviews based on maximum heterogeneity sampling. Thirty-five semi-structured interviews were undertaken (14 males; 21 females). The interview schedule covered: employment situation, workplace challenges, workplace supports, coping strategies, motivations, future employment options and any other resources utilised. Inductive content analysis was undertaken using a grounded theory approach to systematically explore the data. Results Three key themes were identified: barriers to working productively, enablers to working productively, disclosing my condition at work. A key determinant of maintaining productive employment was a supportive employer. In addition, flexibility in the work organisation was also pivotal in maintaining sustainable, productive employment. An important issue emerged with regard to disclosure of one's condition to an employer. For some, this was a significant barrier to employment. Conclusions To ensure sustainable employment is attainable for those with persistent pain conditions, a good match is required between an employee and their work. Workplace accommodations may assist with improving job fit but this requires disclosure of a condition to an employer. Weighing up the risks and benefits of disclosure is difficult, and may be assisted by knowledge of available supports to assist with maintaining ongoing employment.
Cerin, Ester; Mitáš, Josef; Cain, Kelli L; Conway, Terry L; Adams, Marc A; Schofield, Grant; Sarmiento, Olga L; Reis, Rodrigo Siqueira; Schipperijn, Jasper; Davey, Rachel; Salvo, Deborah; Orzanco-Garralda, Rosario; Macfarlane, Duncan J; De Bourdeaudhuij, Ilse; Owen, Neville; Sallis, James F; Van Dyck, Delfien
2017-03-20
To more accurately quantify the potential impact of the neighbourhood environment on adults' physical activity (PA), it is important to compare environment-PA associations between periods of the day or week when adults are more versus less likely to be in their neighbourhood and utilise its PA resources. We examined whether, among adults from 10 countries, associations between objectively-assessed neighbourhood environment attributes and moderate-to-vigorous physical activity (MVPA) varied by time of the day and day of the week. The secondary aim was to examine whether such associations varied by employment status, gender and city. This cross-sectional study included 6,712 adults from 14 cities across 10 countries with ≥1 day of valid accelerometer-assessed MVPA and complete information on socio-demographic and objectively-assessed environmental characteristics within 0.5 and 1 km street-network buffers around the home. Accelerometer measures (MVPA min/h) were created for six time periods from early morning until late evening/night, for weekdays and weekend days separately. Associations were estimated using generalized additive mixed models. Time of the day, day of week, gender and employment status were significant moderators of environment-MVPA associations. Land use mix was positively associated with MVPA in women who were employed and in men irrespective of their employment status. The positive associations between MVPA and net residential density, intersection density and land use mix were stronger in the mornings of weekdays and the afternoon/evening periods of both weekdays and weekend days. Associations between number of parks and MVPA were stronger in the mornings and afternoon/evenings irrespective of day of the week. Public transport density showed consistent positive associations with MVPA during weekends, while stronger effects on weekdays were observed in the morning and early evenings. This study suggests that space and time constraints in adults' daily activities are important factors that determine the impact of neighbourhood attributes on PA. Consideration of time-specific associations is important to better characterise the magnitude of the effects of the neighbourhood environment on PA. Future research will need to examine the contribution of built environment characteristics of areas surrounding other types of daily life centres (e.g., workplaces) to explaining adults' PA at specific times of the day.
NASA Astrophysics Data System (ADS)
Pardede, Astrid; Budihardjo, Mochamad Arief; Purwono
2018-02-01
Oyster mushroom (Pleurotus ostreatus) can be utilized as biocoagulant since it has chitin cell wall. Chitin has characteristics of bioactivity, biodegradability, absorption and could bind the metal ions. In this study, Oyster Mushroom is micronized and mixed with wastewater to treat turbidity and Total Suspended Solid (TSS) using coagulation-flocculation process employed jartest method. Various doses of Oyster mushroom, 600 mg/l, 1000 mg/l, and 2000 mg/l were tested in several rapid mixing rates which were 100 rpm, 125 rpm, and 150 rpm for 3 minutes followed by 12 minutes of slow mixing at 45 rpm. The mixture then was settled for 60 minutes with pH level maintained at 6-8. The result showed that the Oyster mushroom biocoagulant was able to remove 84% of turbidity and 90% of TSS. These reductions were achieved with biocoagulant dose of 600 mg/ L at 150 rpm mixing rate.
Toward topology-based characterization of small-scale mixing in compressible turbulence
NASA Astrophysics Data System (ADS)
Suman, Sawan; Girimaji, Sharath
2011-11-01
Turbulent mixing rate at small scales of motion (molecular mixing) is governed by the steepness of the scalar-gradient field which in turn is dependent upon the prevailing velocity gradients. Thus motivated, we propose a velocity-gradient topology-based approach for characterizing small-scale mixing in compressible turbulence. We define a mixing efficiency metric that is dependent upon the topology of the solenoidal and dilatational deformation rates of a fluid element. The mixing characteristics of solenoidal and dilatational velocity fluctuations are clearly delineated. We validate this new approach by employing mixing data from direct numerical simulations (DNS) of compressible decaying turbulence with passive scalar. For each velocity-gradient topology, we compare the mixing efficiency predicted by the topology-based model with the corresponding conditional scalar variance obtained from DNS. The new mixing metric accurately distinguishes good and poor mixing topologies and indeed reasonably captures the numerical values. The results clearly demonstrate the viability of the proposed approach for characterizing and predicting mixing in compressible flows.
Rapid Confined Mixing Using Transverse Jets Part 2: Multiple Jets
NASA Astrophysics Data System (ADS)
Forliti, David; Salazar, David
2012-11-01
An experimental study has been conducted at the Air Force Research Laboratory at Edwards Air Force Base to investigate the properties of confined mixing devices that employ transverse jets. The experiment considers the mixing of water with a mixture of water and fluorescein, and planar laser induced fluorescence was used to measure instantaneous mixture fraction distributions in the cross section view. Part one of this study presents the scaling law development and results for a single confined transverse jet. Part two will describe the results of configurations including multiple transverse jets. The different regimes of mixing behavior, ranging from under to overpenetration of the transverse jets, are characterized in terms of a new scaling law parameter presented in part one. The level of unmixedness, a primary metric for mixing device performance, is quantified for different jet diameters, number of jets, and relative flow rates. It is apparent that the addition of a second transverse jet provides enhanced scalar uniformity in the main pipe flow cross section compared to a single jet. Three and six jet configurations also provide highly uniform scalar distributions. Turbulent scalar fluctuation intensities, spectral features, and spatial eigenfunctions using the proper orthogonal decomposition will be presented. Distribution A: Public Release, Public Affairs Clearance Number: 12656.
NASA Astrophysics Data System (ADS)
Wang, H.; Kravitz, B.; Rasch, P. J.; Morrison, H.; Solomon, A.
2014-12-01
Previous process-oriented modeling studies have highlighted the dependence of effectiveness of cloud brightening by aerosols on cloud regimes in warm marine boundary layer. Cloud microphysical processes in clouds that contain ice, and hence the mechanisms that drive aerosol-cloud interactions, are more complicated than in warm clouds. Interactions between ice particles and liquid drops add additional levels of complexity to aerosol effects. A cloud-resolving model is used to study aerosol-cloud interactions in the Arctic triggered by strong aerosol emissions, through either geoengineering injection or concentrated sources such as shipping and fires. An updated cloud microphysical scheme with prognostic aerosol and cloud particle numbers is employed. Model simulations are performed in pure super-cooled liquid and mixed-phase clouds, separately, with or without an injection of aerosols into either a clean or a more polluted Arctic boundary layer. Vertical mixing and cloud scavenging of particles injected from the surface is still quite efficient in the less turbulent cold environment. Overall, the injection of aerosols into the Arctic boundary layer can delay the collapse of the boundary layer and increase low-cloud albedo. The pure liquid clouds are more susceptible to the increase in aerosol number concentration than the mixed-phase clouds. Rain production processes are more effectively suppressed by aerosol injection, whereas ice precipitation (snow) is affected less; thus the effectiveness of brightening mixed-phase clouds is lower than for liquid-only clouds. Aerosol injection into a clean boundary layer results in a greater cloud albedo increase than injection into a polluted one, consistent with current knowledge about aerosol-cloud interactions. Unlike previous studies investigating warm clouds, the impact of dynamical feedback due to precipitation changes is small. According to these results, which are dependent upon the representation of ice nucleation processes in the employed microphysical scheme, Arctic geoengineering/shipping could have substantial local radiative effects, but is unlikely to be effective as the sole means of counterbalancing warming due to climate change.
ERIC Educational Resources Information Center
Caukin, Nancy S.
2010-01-01
The purpose of this mixed-methods study was to determine if employing the writing-to-learn strategy known as a "Science Writing Heuristic" would positively effect students' science achievement, science self-efficacy, and scientific epistemological view. The publications "Science for All American, Blueprints for Reform: Project…
Using a Laboratory Simulator in the Teaching and Study of Chemical Processes in Estuarine Systems
ERIC Educational Resources Information Center
Garcia-Luque, E.; Ortega, T.; Forja, J. M.; Gomez-Parra, A.
2004-01-01
The teaching of Chemical Oceanography in the Faculty of Marine and Environmental Sciences of the University of Cadiz (Spain) has been improved since 1994 by the employment of a device for the laboratory simulation of estuarine mixing processes and the characterisation of the chemical behaviour of many substances that pass through an estuary. The…
ERIC Educational Resources Information Center
Long, Michael; Fischer, John
Leading-edge firms (LEFs)--at the forefront of their industry in terms of growth or market share--may influence skill development through diffusion of technology, products, or practices and use of market power to set standards or change customer businesses. Study of LEFs can identify the type and mix of skills needed in the industry. LEFs are…
Wei-Li Jasmine Chen; Chad L. Pierskalla; Theresa L. Goldman; David L. Larsen
2002-01-01
A mix method study designed to explore the meanings, interest, and connections visitors ascribe to three National Park Service sites: National Capital Parks Central, Rock Creek Park, and George Washington Memorial Parkway's Great Falls Park. The researchers employed the focus group interview technique and asked visitors prior to and then after an interpretive...
ERIC Educational Resources Information Center
Reutzel, D. Ray; Smith, John A.; Fawson, Parker C.
2005-01-01
There are few research studies on the effects of teaching comprehension strategies to young children in the primary grades. Using a Dominant-Less Dominant Mixed Model design employing both qualitative and quantitative data collection, we evaluated two approaches for teaching comprehension strategies to 7- and 8-year-old children in four…
ERIC Educational Resources Information Center
Lee, Carrie W.; Walkowiak, Temple A.; Nietfeld, John L.
2017-01-01
The purpose of this study was to investigate the relationship between prospective teachers' (PTs) instructional practises and their efficacy beliefs in classroom management and mathematics teaching. A sequential, explanatory mixed-methods design was employed. Results from efficacy surveys, implemented with 54 PTs were linked to a sample of…
ERIC Educational Resources Information Center
Liu, Shujie; Onwuegbuzie, Anthony J.
2014-01-01
This study employed a partially-mixed concurrent equal-status design to investigate factors motivating Chinese teachers to enter the teaching profession and sources of teacher job satisfaction in China as opposed to those described in the international literature. The data were collected in Jilin Province of China from 510 teachers who…
ERIC Educational Resources Information Center
Bramwell-Lalor, Sharon; Rainford, Marcia
2014-01-01
This paper reports on teachers' use of concept mapping as an alternative assessment strategy in advanced level biology classes and its effects on students' cognitive skills on selected biology concepts. Using a mixed methods approach, the study employed a pre-test/post-test quasi-experimental design involving 156 students and 8 teachers from…
ERIC Educational Resources Information Center
Sanchez-Munoz, Ana
2013-01-01
This study explores various linguistic strategies that characterize what is commonly referred to as "Spanglish"; namely, code-switching, code-mixing, borrowings and other language contact phenomena commonly employed by Chicana/o bilinguals. The analysis of linguistic features is based on creative pieces of writing produced by Chicana/o…
ERIC Educational Resources Information Center
Li, Zhi; Feng, Hui-Hsien; Saricaoglu, Aysel
2017-01-01
This classroom-based study employs a mixed-methods approach to exploring both short-term and long-term effects of Criterion feedback on ESL students' development of grammatical accuracy. The results of multilevel growth modeling indicate that Criterion feedback helps students in both intermediate-high and advanced-low levels reduce errors in eight…
ERIC Educational Resources Information Center
Yaghoubinejad, Hadi; Zarrinabadi, Nourollah; Nejadansari, Dariush
2017-01-01
Research has shown that lack of motivation on either students or teachers' part negatively influences language learning. The latter case is a serious problem in this regard, since an unmotivated teacher will extinguish his learners' enthusiasm and energy for learning. This study employed a mixed-method approach to investigate the demotivating…
Evaluating ICT Integration in Turkish K-12 Schools through Teachers' Views
ERIC Educational Resources Information Center
Aydin, Mehmet Kemal; Gürol, Mehmet; Vanderlinde, Ruben
2016-01-01
The current study aims to explore ICT integration in Turkish K-12 schools purposively selected as a representation of F@tih and non-F@tih public schools together with a private school. A convergent mixed methods design was employed with a multiple case strategy as such it will enable to make casewise comparisons. The quantitative data was…
Investigating Demotivation in Learning English: An Extension to Sakai and Kikuchi's (2009) Framework
ERIC Educational Resources Information Center
Krishnan, K. Sarojani Devi; Aziz, Jalan Raja Muda Abdul; Pathan, Zahid Hussain
2013-01-01
The aim of this research is to investigate the factors of demotivation in L2 learning of Pakistani undergraduates at the University of Balochistan, Quetta. A mixed-methods research design was employed in this study to explore the factors of demotivation. Quantitative data was obtained from the responses of a population of 116 first semester…
ERIC Educational Resources Information Center
Barendregt, Wolmet; Bekker, Tilde M.
2011-01-01
Employing a mixed-method explorative approach, this study examined the in situ use of and opinions about an educational computer game for learning English introduced in three schools offering different levels of freedom to choose school activities. The results indicated that the general behaviour of the children with the game was very different…
ERIC Educational Resources Information Center
Ashbourne, Dianne; Andres, Lesley
2015-01-01
In this study, we explore the impact that parents have on the participation of their children in extracurricular activities (ECAs) in a sample of Canadian parents with children between the ages of four and 17. Employing a concurrent, nested, mixed methods strategy, we use the insights gained through semi-structured interviews with parents to…
Blended Learning: A Mixed-Methods Study on Successful Schools and Effective Practices
ERIC Educational Resources Information Center
Mathews, Anne
2017-01-01
Blended learning is a teaching technique that utilizes face-to-face teaching and online or technology-based practice in which the learner has the ability to exert some level of control over the pace, place, path, or time of learning. Schools that employ this method of teaching often demonstrate larger gains than traditional face-to-face programs…
ERIC Educational Resources Information Center
Scoffham, Stephen
2013-01-01
This article explores some of the challenges of developing a module on global learning with primary initial teacher education (ITE) students studying at a UK university. The research, which employed a mixed methodology, involved around 550 students and eight members of staff over a three-year period. The findings indicate that many students…
Loaiza, Oscar A; Lamas-Ardisana, Pedro J; Jubete, Elena; Ochoteco, Estibalitz; Loinaz, Iraida; Cabañero, Germán; García, Isabel; Penadés, Soledad
2011-04-15
The development of sensors to detect specific weak biological interactions is still today a challenging topic. Characteristics of carbohydrate-protein (lectin) interactions include high specificity and low affinity. This work describes the development of nanostructured impedimetric sensors for the detection of concanavalin A (Con A) binding to immobilized thiolated carbohydrate derivatives (D-mannose or D-glucose) onto screen-printed carbon electrodes (SPCEs) modified with gold nanoparticles. Thiolated D-galactose derivative was employed as negative control to evaluate the selectivity of the proposed methodology. After binding the thiolated carbohydrate to the nanostructured SPCEs, different functionalized thiols were employed to form mixed self-assembled monolayers (SAM). Electrochemical impedance spectroscopy (EIS) was employed as a technique to evaluate the binding of Con A to selected carbohydrates through the increase of electron transfer resistance of the ferri/ferrocyanide redox probe at the differently SAM modified electrodes. Different variables of the assay protocol were studied in order to optimize the sensor performance. Selective Con A determinations were only achieved by the formation of mixed SAMs with adequate functionalized thiols. Important differences were obtained depending on the chain lengths and functional groups of these thiols. For the 3-mercapto-1-propanesulfonate mixed SAMs, the electron transfer resistance varied linearly with the Con A concentration in the 2.2-40.0 μg mL(-1) range for D-mannose and D-glucose modified sensors. Low detection limits (0.099 and 0.078 pmol) and good reproducibility (6.9 and 6.1%, n=10) were obtained for the D-glucose and D-mannose modified sensors, respectively, without any amplification strategy. © 2011 American Chemical Society
Osmium Isotope Evidence for an S-Process Carrier in Primitive Chondrites
NASA Technical Reports Server (NTRS)
Brandon, A. D.; Puchtel, I. S.; Humayun, M.; Zolensky, M.
2005-01-01
The degree of isotopic mixing in the solar nebula and the nature of pre-solar components that have contributed to our solar system remain subjects of vigorous debate. Isotopic anomalies have been identified in Ca-Al inclusions in chondrites [1-4]. This indicates that refractory pre-solar components were not completely homogenized or processed away at the high temperatures experienced by CAIs. Pre-solar grains (SiC, C, etc.) are prevalent in primitive chondrites, and preserve isotopic heterogeneity resulting from the nucleosynthetic processes occurring in the stars from which these grains formed [2,4]. Several recent studies employing precise techniques for measuring Ru, Mo and Zr isotopes in bulk meteorites, have come up with varying conclusions on the degree of effectiveness of nebular mixing on the scale of bulk meteorite material. Some of these studies have reported isotopic anomalies in Mo and Ru [3,5-7], while others have not observed anomalies in Mo, Ru, or Zr [8-10]. Debate over the quality of the data, the normalization techniques employed, the absence or presence of isobaric interferences during the measurements on different types of instruments (e.g. TIMS versus ICP-MS), and other factors, has ensued [11,12].
Optimising the emergency to ward handover process: A mixed methods study.
Bakon, Shannon; Millichamp, Tracey
2017-11-01
The effective handover of patient health data from the emergency department to other hospital units is integral for the continuity of patient care. Yet no handover process has been identified as superior to others within this context. This study within a regional Australian hospital employed mixed methods approach including focus groups and key stakeholder consultation to develop a handover form appropriate for patient transfer from the emergency department to a variety of clinical areas. Paper-based surveys and audits were then employed to evaluate the implementation and understand staff perceptions of the form. The implementation of a patient handover form within the emergency setting was well received. Participants indicated that the form is clear, well designed and easy to navigate. It provided prompts to standardise their clinical handover and increased their accountability and responsibility within this process. To deliver an optimal nursing handover from the emergency department to various wards handovers should be structured and provide standardised content. The positive reception and use of this form provides evidence that a structured handover process can ensure standardisation of emergency department to ward nursing handovers. Copyright © 2017 College of Emergency Nursing Australasia. Published by Elsevier Ltd. All rights reserved.
Burgess, Diana J; Fu, Steven S; Noorbaloochi, Siamak; Clothier, Barbara A; Ricards, Jennifer; Widome, Rachel; van Ryn, Michelle
2009-12-01
This study examines the presence and correlates of gender disparities in smoking cessation among lower income smokers prescribed nicotine replacement medication. We examined quit rates (7-day abstinence point prevalence) among a cohort of smokers who filled prescriptions for nicotine replacement (N = 1,782), using Minnesota Health Care Programs' (e.g., Medicaid) pharmacy claims databases (2005-2006) and mixed-mode survey protocols. A cohort of smokers who recently filled a prescription for nicotine replacement was stratified by race, and then subjects were selected by simple random sample from each race, oversampling the nonWhite groups (N = 1,782). The primary outcome was point prevalence of 7-day abstinence, and outcomes were assessed about 8 months after the nicotine replacement therapy (NRT) index prescription fill date using a mixed-mode survey protocol. Final interaction models were constructed using backward elimination. Abstinence rates were 11.4% among women and 19.2% among men (p = .02) and remained marginally significant after controlling for demographics, mental and physical health, period of cigarette abstinence, social environment, religious attendance, perceived stress, and NRT prescription type (p = .08). There was a significant Gender x Employment interaction (p = .02). Among men, quit rates were higher among the employed (26%) compared with the unemployed (16%); among women, quit rates were lower among those who were employed (8%) compared with those who were unemployed (14%). Results suggest the need for research on factors specific to women's work roles or workplaces that inhibit cessation as well as cessation programs tailored to low-income, employed female smokers. On-site workplace interventions and flexible counseling programs may be especially beneficial.
Association between employment status change and depression in Korean adults
Park, Eun-Cheol; Jang, Suk-Yong; Kwon, Jeoung A; Kim, Sun Jung; Cho, Kyoung-hee; Choi, Jae-Woo; Kim, Jae-Hyun; Park, Sohee
2016-01-01
Objectives This study investigated the association between employment status and depression. Methods Data from the Korea Welfare Panel Study (KOWEPS) collected from 2008 to 2011 were used. A total of 7368 subjects were included in this study after exclusion of subjects with missing data and those who were self-employed or could not work. Depression was assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). Employment status, age, sex, region, education, marital status, income, head of household, self-rated health, smoking status, drinking habits, and the current year's and the previous year's CES-D scores were included in the model as independent variables. A generalised linear mixed-effects model for longitudinal binary data was used. Results Compared with those who were permanently employed, individuals who moved from permanent to precarious employment (OR 1.45, 95% CI 1.23 to 1.70) or to unemployment (OR 1.78, 95% CI 1.30 to 2.43) and from precarious employment to unemployment (OR 1.65, 95% CI 1.32 to 2.06) showed a significantly increased the odds of having depression. Continuing precarious employment (OR 1.54, 95% CI 1.30 to 1.83) or unemployment (OR 1.45, 95% CI 1.23 to 1.70) also significantly increased the odds of having depression. These results were particularly identified in men and head of household women. The effects were not significant among non-head of household women. Conclusions Precarious employment and unemployment were clearly associated with having depression. In addition, in view of our findings, policy makers should consider sex and head of household status when developing welfare policies. The inequity between precarious jobs and permanent jobs should be tackled. PMID:26932136
State variation in health insurance coverage for U.S. citizen children of immigrants.
Acevedo-Garcia, Dolores; Stone, Lisa Cacari
2008-01-01
In this paper we compare health insurance coverage for U.S. citizen children in all-citizen and mixed families in the fifteen states with the largest share of children in mixed families. Insurance coverage is lower and state variation in coverage is higher for children in mixed families vis-à-vis children in all-citizen families. The main challenges for states are tackling uninsurance among all low-income children and addressing the very low rates of employer-sponsored insurance for all low-income children and for children in all mixed families, regardless of income. We discuss state policy options to address the needs of children in mixed families.
Hilton, Gillean; Unsworth, Carolyn A; Stuckey, Ruth; Murphy, Gregory C
2018-01-01
Vocational potential in people with spinal cord injury (SCI) are unrealised with rates of employment substantially lower than in the labour force participation of the general population and the pre-injury employment rates. To understand the experience and pathway of people achieving employment outcome after traumatic spinal cord injury by; classifying participants into employment outcome groups of stable, unstable and without employment; identifying pre and post-injury pathways for participants in each group and, exploring the experiences of people of seeking, gaining and maintaining employment. Thirty-one participants were interviewed. Mixed methods approach including interpretive phenomenological analysis and vocational pathway mapping of quantitative data. The most common pathway identified was from study and work pre-injury to stable employment post-injury. Four super-ordinate themes were identified from the interpretive phenomenological analysis; expectations of work, system impacts, worker identity and social supports. Implications for clinical practice include fostering cultural change, strategies for system navigation, promotion of worker identity and optimal use of social supports. The findings increase insight and understanding of the complex experience of employment after spinal cord injury. There is opportunity to guide experimental research, policy development and education concerning the complexity of the return to work experience and factors that influence pathways.
ERIC Educational Resources Information Center
Jung, Jae Yup; Young, Marie
2017-01-01
A mixed-methods design was employed to identify the cognitive processes that lead to occupational/career indecision for economically disadvantaged adolescents of high intellectual ability. In the first phase, interview data collected from 26 economically disadvantaged intellectually gifted Australian adolescents were analyzed using grounded theory…
ERIC Educational Resources Information Center
Kim, Amber K.
2012-01-01
This research study examined constructs and beliefs essential to culturally responsive teachers for the purpose of understanding corps members' needs and promoting culturally responsive pedagogy (CRP) in the Colorado region of Teach for America (TFA). This study employed a transformative, sequential mixed methods design with a theoretical lens of…
An Essential Job: Marketing the Placement Office to Faculty and Employers.
ERIC Educational Resources Information Center
Bullock, Marcy; Brooks, Jennifer E.
1994-01-01
Discusses the use of marketing by college career services offices. Defines marketing, explains the marketing process, and discusses needs assessment. Section on the marketing mix identifies the product, price, place, and promotion components of both faculty and employer marketing programs. Includes results, in tabular form, of faculty survey on…
Evidence on Private Sector Training. Background Paper No. 7b.
ERIC Educational Resources Information Center
Mangum, Stephen L.
Today's postindustrial or information age requires a different mix and a more advanced level of basic employability skills than those needed in the industrial age. As a result, the workplace is now demanding a higher entrance level of employability skills than the schools have previously been asked to provide. In addition, information technology…
ERIC Educational Resources Information Center
Cianca, Sherri
2012-01-01
The Ethiopian government has called for educational improvement, emphasizing the employment of active, student-centered pedagogy. One way of maximizing an interactive learning approach involves blending a cross-age reading buddies program with high-quality, culturally relevant children's literature. Employing descriptive, mixed-method research,…
Line mixing effects in isotropic Raman spectra of pure N{sub 2}: A classical trajectory study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ivanov, Sergey V., E-mail: serg.vict.ivanov@gmail.com; Boulet, Christian; Buzykin, Oleg G.
2014-11-14
Line mixing effects in the Q branch of pure N{sub 2} isotropic Raman scattering are studied at room temperature using a classical trajectory method. It is the first study using an extended modified version of Gordon's classical theory of impact broadening and shift of rovibrational lines. The whole relaxation matrix is calculated using an exact 3D classical trajectory method for binary collisions of rigid N{sub 2} molecules employing the most up-to-date intermolecular potential energy surface (PES). A simple symmetrizing procedure is employed to improve off-diagonal cross-sections to make them obeying exactly the principle of detailed balance. The adequacy of themore » results is confirmed by the sum rule. The comparison is made with available experimental data as well as with benchmark fully quantum close coupling [F. Thibault, C. Boulet, and Q. Ma, J. Chem. Phys. 140, 044303 (2014)] and refined semi-classical Robert-Bonamy [C. Boulet, Q. Ma, and F. Thibault, J. Chem. Phys. 140, 084310 (2014)] results. All calculations (classical, quantum, and semi-classical) were made using the same PES. The agreement between classical and quantum relaxation matrices is excellent, opening the way to the analysis of more complex molecular systems.« less
Ruthenium-based, inert oxide electrodes for impregnating active materials in nickel plaques
NASA Astrophysics Data System (ADS)
Manoharan, R.; Uma, M.
Titanium electrodes coated with mixed ruthenium-iridium-titanium oxides are tested as inert counter electrodes for impregnating active materials in porous nickel plaques. The latter are to be used as the positive electrodes in nickel/cadmium cells. Weight losses and variations in bath voltage have been monitored while using these electrodes in the impregnation bath. A 2.85 Ah nickel/cadmium cell has been constructed using nickel electrodes developed by employing the coated electrodes of this study. The performances of these coated electrodes are compared with those of platinum electrodes that are currently employed by nickel/cadmium battery manufacturers. The results are found to be satisfactory.
Employment Trajectories Beyond Retirement.
Burkert, Carola; Hochfellner, Daniela
2017-01-01
Within the political and academic debate on working longer, post-retirement employment is discussed as an alternative to maintain older workers in the labor market. Our article enhances this discussion by studying determinants of transitions into post-retirement jobs within differing work environments of birth cohorts 1940-1942. We estimate proportional subhazard models accounting for competing risks using unique German social security data linked to pension accounts. Our findings suggest that individuals' preferences to take up post-retirement jobs are not mutually exclusive. Our study provides evidence that taking up post-retirement jobs is related to seeking financial security, continuity, and work ability, suggesting that public policy has to develop target-oriented support through a public policy mix of different measures aligned to the different peer groups in the labor market.
Mustard, Cameron A; Skivington, Kathryn; Lay, Morgan; Lifshen, Marni; Etches, Jacob; Chambers, Andrea
2017-06-17
This study describes the process and outcomes of the implementation of a strengthened disability management policy in a large Canadian healthcare employer. Key elements of the strengthened policy included an emphasis on early contact, the training of supervisors and the integration of union representatives in return-to-work (RTW) planning. The study applied mixed methods, combining a process evaluation within the employer and a quasi-experimental outcome evaluation between employers for a 3-year period prior to and following policy implementation in January 2012. Staff in the implementation organisation (n=4000) and staff in a peer group of 29 large hospitals (n=1 19 000). Work disability episode incidence and duration. Both qualitative and quantitative measures of the implementation process were predominantly positive. Over the 6-year observation period, there were 624 work disability episodes in the organisation and 8604 in the comparison group of 29 large hospitals. The annual per cent change in episode incidence in the organisation was -5.6 (95% CI -9.9 to -1.1) comparable to the annual per cent change in the comparison group: -6.2 (-7.2 to -5.3). Disability episode durations also declined in the organisation, from a mean of 19.4 days (16.5, 22.3) in the preintervention period to 10.9 days (8.7, 13.2) in the postintervention period. Reductions in disability durations were also observed in the comparison group: from a mean of 13.5 days (12.9, 14.1) in the 2009-2011 period to 10.5 days (9.9, 11.1) in the 2012-2014 period. The incidence of work disability episodes and the durations of work disability declined strongly in this hospital sector over the 6-year observation period. The implementation of the organisation's RTW policy was associated with larger reductions in disability durations than observed in the comparison group. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Extrusion-mixing compared with hand-mixing of polyether impression materials?
McMahon, Caroline; Kinsella, Daniel; Fleming, Garry J P
2010-12-01
The hypotheses tested were two-fold (a) whether altering the base:catalyst ratio influences working time, elastic recovery and strain in compression properties of a hand-mixed polyether impression material and (b) whether an extrusion-mixed polyether impression material would have a significant advantage over a hand-mixed polyether impression material mixed to the optimum base:catalyst ratio. The polyether was hand-mixed at the optimum (manufacturers recommended) base:catalyst ratios (7:1) and further groups were made by increasing or decreasing the catalyst length by 25%. Additionally specimens were also made from an extrusion-mixed polyether impression material and compared with the optimum hand-mixed base:catalyst ratio. A penetrometer assembly was used to measure the working time (n=5). Five cylindrical specimens for each hand-mixed and extrusion mixed group investigated were employed for elastic recovery and strain in compression testing. Hand-mixing polyether impression materials with 25% more catalyst than that recommended significantly decreased the working time while hand-mixing with 25% less catalyst than that recommended significantly increased the strain in compression. The extrusion-mixed polyether impression material provided similar working time, elastic recovery and strain in compression to the hand-mixed polyether mixed at the optimum base:catalyst ratio.
Lattice Boltzmann Simulation of Electroosmotic Micromixing by Heterogeneous Surface Charge
NASA Astrophysics Data System (ADS)
Tang, G. H.; Wang, F. F.; Tao, W. Q.
Microelectroosmotic flow is usually restricted to low Reynolds number regime, and mixing in these microfluidic systems becomes problematic due to the negligible inertial effects. To gain an improved understanding of mixing enhancement in microchannels patterned with heterogeneous surface charge, the lattice Boltzmann method has been employed to obtain the electric potential distribution in the electrolyte, the flow field, and the species concentration distribution, respectively. The simulation results show that heterogeneous surfaces can significantly disturb the streamlines leading to apparently substantial improvements in mixing. However, the introduction of such a feature can reduce the mass flow rate in the channel. The reduction in flow rate effectively prolongs the available mixing time when the flow passes through the channel and the observed mixing enhancement by heterogeneous surfaces partly results from longer mixing time.
Gledhill, Adam; Forsdyke, Dale; Murray, Eliot
2018-02-20
To systematically review studies examining the role of psychological interventions in injury prevention. The primary research question was: What is the real-world effectiveness of psychological intervention in preventing sports injuries? Mixed methods systematic review with best evidence synthesis. CINAHL, MEDLINE, PsycARTICLES, PsycINFO, SPORTDiscus, Science Direct and PubMed. Randomised controlled trials (RCT), non-RCTs that included a comparison group, before and after study designs and qualitative methods. Studies were required to outline specific unimodal or multimodal psychological interventions used in relation to injury prevention in the real-world setting. Studies were independently appraised with the Mixed Methods Appraisal Tool. Thirteen papers (incorporating 14 studies) met the eligibility criteria, of which 93% (13/14) reported a decrease in injury rates (effect size range=0.2-1.21). There was an overall moderate risk of bias in reporting (52%). There is a dominance of stress management-based interventions in literature due to the prominence of the model of stress and athletic injury within the area. Psychological interventions demonstrate small (0.2) to large (1.21) effects on sports injury rates. The research area demonstrates a cumulative moderate risk in reporting bias (52%). CRD42016035879. © 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.
Conversion of blackbody radiation into laser energy
NASA Technical Reports Server (NTRS)
Mcinville, R. M.; Hassan, H. A.
1982-01-01
By employing detailed kinetic models, three concepts which utilize a blackbody cavity for the conversion of solar energy into laser energy using a CO2 lasant are analyzed and compared. In the first, the blackbody radiation is used to excite flowing CO2 directly. The second and third employ a mixing laser concept with CO and N2 being the donor gases. The CO is optically pumped while thermal heating excites the N2. Blackbody temperatures ranging from 1500 deg K - 2500 deg K are considered. Based on calculated laser power output per unit flow rate of CO2, it appears that the N2-CO2 mixing laser is the most attractive system.
Verifying mixing in dilution tunnels How to ensure cookstove emissions samples are unbiased
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, Daniel L.; Rapp, Vi H.; Caubel, Julien J.
A well-mixed diluted sample is essential for unbiased measurement of cookstove emissions. Most cookstove testing labs employ a dilution tunnel, also referred to as a “duct,” to mix clean dilution air with cookstove emissions before sampling. It is important that the emissions be well-mixed and unbiased at the sampling port so that instruments can take representative samples of the emission plume. Some groups have employed mixing baffles to ensure the gaseous and aerosol emissions from cookstoves are well-mixed before reaching the sampling location [2, 4]. The goal of these baffles is to to dilute and mix the emissions stream withmore » the room air entering the fume hood by creating a local zone of high turbulence. However, potential drawbacks of mixing baffles include increased flow resistance (larger blowers needed for the same exhaust flow), nuisance cleaning of baffles as soot collects, and, importantly, the potential for loss of PM2.5 particles on the baffles themselves, thus biasing results. A cookstove emission monitoring system with baffles will collect particles faster than the duct’s walls alone. This is mostly driven by the available surface area for deposition by processes of Brownian diffusion (through the boundary layer) and turbophoresis (i.e. impaction). The greater the surface area available for diffusive and advection-driven deposition to occur, the greater the particle loss will be at the sampling port. As a layer of larger particle “fuzz” builds on the mixing baffles, even greater PM2.5 loss could occur. The micro structure of the deposited aerosol will lead to increased rates of particle loss by interception and a tendency for smaller particles to deposit due to impaction on small features of the micro structure. If the flow stream could be well-mixed without the need for baffles, these drawbacks could be avoided and the cookstove emissions sampling system would be more robust.« less
McHugo, Gregory J; Drake, Robert E; Xie, Haiyi; Bond, Gary R
2012-07-01
Employment promotes recovery for persons with serious mental illness by providing extra income and a valued social role, but the impact of employment on other psychosocial and clinical outcomes remains unclear. This study examined non-vocational outcomes in relation to steady employment over 10 years among people with serious mental illness and co-occurring substance use disorders. Researchers interviewed people with co-occurring disorders at baseline and yearly for 10 years and tracked employment in relation to five non-vocational outcomes: independent living, psychiatric symptoms, substance use disorder, healthy (non-substance-abusing) relationships, and life satisfaction. Latent class trajectory analysis identified steady workers, and mixed-effects regression models compared steady workers with non-workers. Both steady workers (n=51) and non-workers (n=79) improved substantially; for example, a majority of each group achieved independent housing and stable remission of substance use disorders. Steady workers achieved independent housing and higher quality of life during the first 5 years of follow-up, but the two groups achieved similar outcomes by 10 years. People with co-occurring disorders can improve markedly. Those with steady employment may improve faster, but those without employment may achieve similar long-term outcomes at a slower pace. Copyright © 2012 Elsevier B.V. All rights reserved.
Butler, Claire; Brigden, Charlotte; Gage, Heather; Williams, Peter; Holdsworth, Laura; Greene, Kay; Wee, Bee; Barclay, Stephen; Wilson, Patricia
2018-05-16
Hospice at home (HAH) services aim to enable patients to be cared for and die in their place of choice, if that is at home, and to achieve a 'good death'. There is a considerable range of HAH services operating in England. The published evidence focuses on evaluations of individual services which vary considerably, and there is a lack of consistency in terms of the outcome measures reported. The evidence, therefore, does not provide generalisable information, so the question 'What are the features of hospice at home service models that work, for whom, and under what circumstances?' remains unanswered. The study aims to answer this question. This is a mixed-methods study in three phases informed by realist evaluation methodology. All HAH services in England will be invited to participate in a telephone survey to enable the development of a typology of services. In the second phase, case study sites representing the different service types will collect patient data and recruit carers, service managers and commissioners to gather quantitative and qualitative data about service provision and outcomes. A third phase will synthesise and refine the results through consensus workshops. The first survey phase has university ethics approval and the second phase, Integrated Research Application System (IRAS) and Health Research Authority (HRA) approval (IRAS ID:205986, REC:17/LO/0880); the third phase does not require ethics approval. Dissemination will be facilitated by project coapplicants with established connections to national policy-making forums, in addition to publications, conference presentations and reports targeted to service providers and commissioners. © 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.
Watkins, Daphne C.; Wharton, Tracy; Mitchell, Jamie A.; Matusko, Niki; Kales, Helen
2016-01-01
The purpose of this study was to explore the role of non-spousal family support on mental health among older, church-going African American men. The mixed methods objective was to employ a design that used existing qualitative and quantitative data to explore the interpretive context within which social and cultural experiences occur. Qualitative data (n=21) were used to build a conceptual model that was tested using quantitative data (n= 401). Confirmatory factor analysis indicated an inverse association between non-spousal family support and distress. The comparative fit index, Tucker-Lewis fit index, and root mean square error of approximation indicated good model fit. This study offers unique methodological approaches to using existing, complementary data sources to understand the health of African American men. PMID:28943829
NASA Astrophysics Data System (ADS)
Cook, Kristina J.; Fan, YanFeng; Hassan, Ibrahim
2012-05-01
Micromixers are vital components in micro total analysis systems. It is desirable to develop micromixers which are capable of rapidly mixing two or more fluids in a small footprint area, while minimizing mechanical losses. A novel planar scaled-up passive micromixer is experimentally investigated in this study. The design incorporates a 7-substream uneven interdigital inlet which supplies two liquid species in a parallel arrangement and promotes diffusion along the side walls. Forty-eight staggered teardrop-shaped obstruction elements located along the channel length combined with 32 side walls protrusions increase the two-fluid interfacial area while converging the flow due to periodic reductions in cross-sectional area. The scaled-up micromixer has a mixing channel length of 110 mm with a mixing channel height and width of 2 and 5 mm, respectively. Experimental investigations are carried out at four locations along the channel length and at Reynolds numbers equal to 1, 5, 10, 25, 50, and 100, where the Reynolds number is calculated based on total two-fluid flow and the mixing channel hydraulic diameter. Flow visualization is employed to study flow patterns, while induced fluorescence (IF), using de-ionized water and low concentration Rhodamine 6G solutions, provides mixing efficiency data. Results show a change in dominant mixing mechanism from mass diffusion to mass advection, with a critical Reynolds number of 25. At high Reynolds numbers, the formation of additional lamellae is observed, as is the formation of Dean vortices in the vicinity of the teardrop obstructions. Of the tested cases, the highest outlet mixing efficiency, 68.5%, is achieved at a Reynolds number of 1, where mass diffusion dominates. At low Reynolds numbers, superior mixing efficiency is due primarily to the implementation of the uneven interdigital inlet. A comparable mixing length is proposed to allow for reasonable comparison with published studies.
NASA Astrophysics Data System (ADS)
Widyastuti, Fajarin, Rindang; Pratiwi, Vania Mitha; Kholid, Rifki Rachman; Habib, Abdulloh
2018-04-01
In this study, RAM composite has been succesfully synthesized by mixing BaM as magnetic materials and PANI as conductive materials. BaM and PANI materials were prepared separately by solid state method and polymerization method, respectively. To investigated the presence of BaM phase and magnetic property of the as prepared BaM, XRD pert PAN analytical and VSM 250 Dexing Magnet were employed. Inductance Capacitance Resistance technique was carried out to measure electrical conductivity of the synthesized PANI materials. In order to further characterized the structural features of BaM and PANI, SEM-EDX FEI 850 and FTIR characterizations were conducted. RAM composite was prepared by mixing BaM and PANI powders with ultrasonic cleaner. Afterwards, VNA (Vector Network Analyzer) characterization was carried out to determine reflection loss value of RAM by applying mixed RAM composite and epoxy paint on aluminum plate using spray gun. Microscopic characterization was employed to investigated the distribution of RAM particles on the substrate. It was found that reflection loss value as low as -27.153 dB was achieved when applied 15 wt% BaM/PANi composite at 100.6 µm thickness. In addition, the absorption of electromagnetic waves value increase as the addition of RAM composite composition increases.
Razali, Sheriza Mohd; Marin, Arnaldo; Nuruddin, Ahmad Ainuddin; Shafri, Helmi Zulhaidi Mohd; Hamid, Hazandy Abdul
2014-01-01
Various classification methods have been applied for low resolution of the entire Earth's surface from recorded satellite images, but insufficient study has determined which method, for which satellite data, is economically viable for tropical forest land use mapping. This study employed Iterative Self Organizing Data Analysis Techniques (ISODATA) and K-Means classification techniques to classified Moderate Resolution Imaging Spectroradiometer (MODIS) Surface Reflectance satellite image into forests, oil palm groves, rubber plantations, mixed horticulture, mixed oil palm and rubber and mixed forest and rubber. Even though frequent cloud cover has been a challenge for mapping tropical forests, our MODIS land use classification map found that 2008 ISODATA-1 performed well with overall accuracy of 94%, with the highest Producer's Accuracy of Forest with 86%, and were consistent with MODIS Land Cover 2008 (MOD12Q1), respectively. The MODIS land use classification was able to distinguish young oil palm groves from open areas, rubber and mature oil palm plantations, on the Advanced Land Observing Satellite (ALOS) map, whereas rubber was more easily distinguished from an open area than from mixed rubber and forest. This study provides insight on the potential for integrating regional databases and temporal MODIS data, in order to map land use in tropical forest regions. PMID:24811079
Razali, Sheriza Mohd; Marin, Arnaldo; Nuruddin, Ahmad Ainuddin; Shafri, Helmi Zulhaidi Mohd; Hamid, Hazandy Abdul
2014-05-07
Various classification methods have been applied for low resolution of the entire Earth's surface from recorded satellite images, but insufficient study has determined which method, for which satellite data, is economically viable for tropical forest land use mapping. This study employed Iterative Self Organizing Data Analysis Techniques (ISODATA) and K-Means classification techniques to classified Moderate Resolution Imaging Spectroradiometer (MODIS) Surface Reflectance satellite image into forests, oil palm groves, rubber plantations, mixed horticulture, mixed oil palm and rubber and mixed forest and rubber. Even though frequent cloud cover has been a challenge for mapping tropical forests, our MODIS land use classification map found that 2008 ISODATA-1 performed well with overall accuracy of 94%, with the highest Producer's Accuracy of Forest with 86%, and were consistent with MODIS Land Cover 2008 (MOD12Q1), respectively. The MODIS land use classification was able to distinguish young oil palm groves from open areas, rubber and mature oil palm plantations, on the Advanced Land Observing Satellite (ALOS) map, whereas rubber was more easily distinguished from an open area than from mixed rubber and forest. This study provides insight on the potential for integrating regional databases and temporal MODIS data, in order to map land use in tropical forest regions.
Experiential environmental learning: A case study of innovative pedagogy in Baja Sur, Mexico
NASA Astrophysics Data System (ADS)
Schneller, Andrew Jon
This mixed methods case study describes an innovative two-semester middle school environmental learning course that departs from traditional Mexican expository pedagogy through the incorporation of experiential and service learning. This research takes place in a small middle school in Pescadero, Baja California Sur, Mexico. The research approach utilized in the study adds to the handful of studies in this cross-disciplinary field by employing quantitative methodologies to measure course outcomes on student environmental knowledge, perceptions, and actions, while simultaneously qualitatively describing the behavioral, educational, environmental, and social experiences of students. This research employs Dewey's theories of experience---as well as those of more contemporary authenticity theorists---in order to identify the philosophies that advocate incorporating experiential pedagogy within the curriculum. Implications for Mexican educational policy, practical pedagogical applications, and theory are discussed.
NASA Astrophysics Data System (ADS)
Chang, Chih-Chang; Yang, Ruey-Jen
2006-08-01
This paper presents a numerical simulation investigation into electroosmotic flow mixing in three-dimensional microchannels with patterned non-uniform surface zeta potentials. Three types of micromixers are investigated, namely a straight diagonal strip mixer (i.e. the non-uniform surface zeta potential is applied along straight, diagonal strips on the lower wall of the mixing channel), a staggered asymmetric herringbone strip mixer and a straight diagonal/symmetric herringbone strip mixer. A particle tracing algorithm is used to visualize and evaluate the mixing performance of the various mixers. The particle trajectories and Poincaré maps of the various mixers are calculated from the three-dimensional flow fields. The surface charge patterns on the lower walls of the microchannels induce electroosmotic chaotic advection in the low Reynolds number flow regime, and hence enhance the passive mixing effect in the microfluidic devices. A quantitative measure of the mixing performance based on Shannon entropy is employed to quantify the mixing of two miscible fluids. The results show that the mixing efficiency increases as the magnitude of the heterogeneous zeta potential ratio (|ζR|) is increased, but decreases as the aspect ratio (H/W) is increased. The mixing efficiency of the straight diagonal strip mixer with a length ratio of l/W = 0.5 is slightly higher than that obtained from the same mixer with l/W = 1.0. Finally, the staggered asymmetric herringbone strip mixer with θ = 45°, ζR = -1, l/W = 0.5 and H/W = 0.2 provides the optimal mixing performance of all the mixers presented in this study.
Jamrah, Ahmad; Al-Futaisi, Ahmed; Hassan, Hossam; Al-Oraimi, Salem
2007-01-01
This paper presents a study that aims at evaluating the leaching characteristics of petroleum contaminated soils as well as their application in hot mix asphalt concrete. Soil samples are environmentally characterized in terms of their total heavy metals and hydrocarbon compounds and leachability. The total petroleum hydrocarbon (TPH) present in the PCS before and after treatment was determined to be 6.8% and 5.3% by dry weight, indicating a reduction of 1% in the TPH of PCS due to the current treatment employed. Results of the total heavy metal analysis on soils indicate that the concentrations of heavy metals are lower when extraction of the soil samples is carried out using hexane in comparison to TCE. The results show that the clean soils present in the vicinity of contaminated sites contain heavy metals in the following decreasing order: nickel (Ni), followed by chromium (Cr), zinc (Zn), copper (Cu), lead (Pb), and vanadium (V). The current treatment practice employed for remediation of the contaminated soil reduces the concentrations of nickel and chromium, but increases the concentrations of all remaining heavy metals.
Functional Stability of a Mixed Microbial Consortium Producing PHA From Waste Carbon Sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
David N. Thompson; Erik R. Coats; William A. Smith
2006-04-01
Polyhydroxyalkanoates (PHAs) represent an environmentally-effective alternative to synthetic thermoplastics; however, current production practices are not sustainable. In this study, PHA production was accomplished in sequencing batch bioreactors utilizing real wastewaters and mixed microbial consortia from municipal activated sludge as inoculum. Polymer production reached 85%, 53%, and 10% of the cell dry weight from methanol-enriched pulp-and-paper mill foul condensate, fermented municipal primary solids, and biodiesel wastewater, respectively. Employing denaturing gradient gel electrophoresis of 16S-rDNA from PCR-amplified DNA extracts, distinctly different communities were observed between and within wastewaters following enrichment. Most importantly, functional stability was maintained despite differing and contrasting microbial populations.
Pandey, Binod; Tan, Yih Horng; Fujikawa, Kohki; Demchenko, Alexei V.
2013-01-01
We have prepared SAMs containing 8-mercaptooctyl α-D-mannopyranoside, either as a single component or in mixed SAMs with n-octanethiol on flat gold surfaces and on nanoporous gold. Electrochemical impedance spectroscopy showed that the mixed SAMs on flat gold surfaces showed the highest Con A binding near 1:9 solution molar ratio of thiolatedα-mannoside to n-octanethiol whereas those on NPG showed the highest response at 1:19 solution molar ratio of thiolated α-mannoside to n-octanethiol. Atomic force microscopy was employed to image the monolayers, and also to image the bound Con A protein. PMID:23519474
Why employers need to rethink how they buy health care.
Galvin, Robert S; Delbanco, Suzanne
2005-01-01
Employers will continue to have a key role in the U.S. health system. Unfortunately, their purchasing practices have fallen far short of ideal. Large employers can lead the way for smaller companies, but by not routinely using competitive bidding or integrating quality into their specifications, they have sent mixed messages to both health plans and providers. Employers need to either get serious about buying health care as individual companies or explore other options. To purchase effectively, both health care expertise and the sustained commitment of senior leadership are needed. Whether employers can reverse their historical performance and become better purchasers is an open question.
Remotely controllable mixing system
NASA Technical Reports Server (NTRS)
Belew, R. R. (Inventor)
1986-01-01
This invention relates to a remotely controllable mixing system in which a plurality of mixing assemblies are arranged in an annular configuration, and wherein each assembly employs a central chamber and two outer, upper and lower chambers. Valves are positioned between chambers, and these valves for a given mixing assembly are operated by upper and lower control rotors, which in turn are driven by upper and lower drive rotors. Additionally, a hoop is compressed around upper control rotors and a hoop is compressed around lower control rotors to thus insure constant frictional engagement between all control rotors and drive rotors. The drive rollers are driven by a motor.
ERIC Educational Resources Information Center
Myerchin, Audra Dawn
2012-01-01
The purpose of this mixed methods study was to explore female faculty members' experiences with maternity leave, while working as a career academic in higher education. Participants consisted of women currently employed in an upper Midwest state at six four-year institutions. An online survey was completed by 121 women, and 30 of these women also…
ERIC Educational Resources Information Center
Griffin, Claire P.; Murtagh, Lelia
2015-01-01
This article outlines the impact of an eight-week Precision Teaching (PT) intervention on the sight vocabulary, reading fluency and reading attainment scores of a group of Irish primary school pupils. This study also sought to evaluate the role of PT in facilitating formative assessment of pupils' progress. Employing a mixed-method approach, this…
ERIC Educational Resources Information Center
McGinnis, J. Randy; Watanabe, Tad
This research employs a mixed theoretical perspective drawing on elements from interactionism and social constructivism. In this study, a discourse analysis is performed on conversations among intra- and inter-institutional mathematics and science teaching faculty participating in reforming content classes for teacher candidates in the Maryland…
ERIC Educational Resources Information Center
Pickard, Katherine E.; Wainer, Allison L.; Bailey, Kathryn M.; Ingersoll, Brooke R.
2016-01-01
Research within the autism spectrum disorder field has called for the use of service delivery models that are able to more efficiently disseminate evidence-based practices into community settings. This study employed telehealth methods in order to deliver an Internet-based, parent training intervention for autism spectrum disorder, ImPACT Online.…
Without the Academic Part, It Wouldn't Be Squash": Youth Development in an Urban Squash Program
ERIC Educational Resources Information Center
Hemphill, Michael A.; Richards, K. Andrew R.
2016-01-01
Purpose: The purpose of this study was to examine youth development outcomes in an Urban Squash program. Methods: A mixed method approach to was employed to address three research questions: 1) to what extent did the Urban Squash program exhibit features of a quality OST program?; 2) what aspects of the Urban Squash program were most valued by…
ERIC Educational Resources Information Center
King, Jim; Aono, Atsuko
2017-01-01
This paper discusses the issue of tolerance of silence within university tutorials from a cross-cultural, comparative perspective. A mixed methods, quasi-experimental approach was employed to measure the length of silence which individual students from samples in Japan and the UK tolerated during a one-to-one staged encounter with their…
ERIC Educational Resources Information Center
Buchholz, Jesse
2017-01-01
Increasing a correctional offender's mindset, resilience, and self-efficacy can be accomplished through the efficient use of technology within correctional education. Correctional facilities that employ the use of technology have the capacity to provide offenders with a tool that will serve them while they are incarcerated and again when they are…
Army Contract Specialists’ Lack of Desire to Become Contracting Officers
2012-05-01
management positions. In researching this matter, the author will utilize a mixed method research approach which employs both qualitative and...literature available and relevance. Chapter 3 presents the methods used to conduct the research and discusses why qualitative interviews and survey research ...This research study will utilize a qualitative method with roots in traditional ethnographic research , in helping to achieve the objective of
ERIC Educational Resources Information Center
Rieckmann, Traci R.; Kovas, Anne E.; Cassidy, Elaine F.; McCarty, Dennis
2011-01-01
State public health authorities are critical to the successful implementation of science based addiction treatment practices by community-based providers. The literature to date, however, lacks examples of state level policy strategies that promote evidence-based practices (EBPs). This mixed-methods study documents changes in two critical…
ERIC Educational Resources Information Center
Bahouth, Saba; Hartmann, David; Willis, Geoff
2014-01-01
The disciplines of logistics and supply chain management have the potential of having many areas of emphasis. Universities that have some kind of emphasis in this field have developed programs that depend on the need of potential employers and their own faculty mix. Several studies have previously looked at how universities deal with this field at…
ERIC Educational Resources Information Center
Almpanis, Timos
2016-01-01
This paper outlines the research design, methodology and methods employed in research conducted in the context of Higher Education Institutions (HEIs) and focuses on the Heads of e-Learning (HeLs) perspective about Technology Enhanced Learning (TEL) by campus-based UK institutions. This paper aims to expand on the research design and the research…
ERIC Educational Resources Information Center
Martin, Monica J.; Blozis, Shelley A.; Boeninger, Daria K.; Masarik, April S.; Conger, Rand D.
2014-01-01
This study of a cohort of 451 adolescents examined associations between trajectories of problem behaviors and the timing of entry into work, marriage, and parenthood. We used data from 12 assessments across adolescence, through emerging adulthood and into young adulthood. We employed 2-phase mixed-effects models to estimate growth in substance use…
Lesaffre, E; Asefa, M; Verbeke, G
1999-04-15
The Jimma Infant Survival Differential Longitudinal Study is an Ethiopian study, set up to establish risk factors affecting infant survival and to investigate socio-economic, maternal and infant-rearing factors that contribute most to the child's early survival. Here, a subgroup of about 1500 children born in Jimma town is examined for their first year's weight gain. Of special interest is the impact of certain cultural practices like uvulectomy, milk teeth extraction and butter swallowing, on child's weight gain; these have never been thoroughly investigated in any study. In this context, the linear mixed model (Laird and Ware) is employed. The purpose of this paper is to illustrate the practical issues when constructing the longitudinal model. Recently developed diagnostics will be used herefor. Finally, special attention will be paid to the two-stage interpretation of the linear mixed model.
Control of Jet Noise Through Mixing Enhancement
NASA Technical Reports Server (NTRS)
Bridges, James; Wernet, Mark; Brown, Cliff
2003-01-01
The idea of using mixing enhancement to reduce jet noise is not new. Lobed mixers have been around since shortly after jet noise became a problem. However, these designs were often a post-design fix that rarely was worth its weight and thrust loss from a system perspective. Recent advances in CFD and some inspired concepts involving chevrons have shown how mixing enhancement can be successfully employed in noise reduction by subtle manipulation of the nozzle geometry. At NASA Glenn Research Center, this recent success has provided an opportunity to explore our paradigms of jet noise understanding, prediction, and reduction. Recent advances in turbulence measurement technology for hot jets have also greatly aided our ability to explore the cause and effect relationships of nozzle geometry, plume turbulence, and acoustic far field. By studying the flow and sound fields of jets with various degrees of mixing enhancement and subsequent noise manipulation, we are able to explore our intuition regarding how jets make noise, test our prediction codes, and pursue advanced noise reduction concepts. The paper will cover some of the existing paradigms of jet noise as they relate to mixing enhancement for jet noise reduction, and present experimental and analytical observations that support these paradigms.
Gillespie, Cheska; Kennedy, Alan R; Edwards, Darren; Dowden, Lee; Daublain, Pierre; Halling, Peter
2013-09-01
Storage of pharmaceutical discovery compounds dissolved in dimethylsulfoxide (DMSO) is commonplace within industry. Often, the DMSO stock solution is added to an aqueous system (e.g. in bioassay or kinetic solubility testing)- since most test compounds are hydrophobic, precipitation could occur. Little is known about the factors affecting this precipitation process at the low (µM) concentrations used in screening analyses. Here, a poorly water soluble test compound (tolnaftate) was used to compare manual and automated pipetting, and explore the effect of mixing variables on precipitation. The amount of drug present in the supernatant after precipitation and centrifugation of the samples was quantified. An unusual result was obtained in three different laboratories: results of experiments performed initially were statistically significantly higher than those performed after a few days in the same lab. No significant differences were found between automated and manual pipetting, including in variability. Vortex mixing was found to give significantly lower supernatant amounts compared to milder mixing types. The mixing employed affects the particle growth of the precipitate. These findings are of relevance to discovery stage bioassay and kinetic solubility analyses.
Cannon, Rex L.; Trudeau, David L.
2008-01-01
Electroencephalographic (EEG) biofeedback has been employed in substance use disorder (SUD) over the last three decades. The SUD is a complex series of disorders with frequent comorbidities and EEG abnormalities of several types. EEG biofeedback has been employed in conjunction with other therapies and may be useful in enhancing certain outcomes of therapy. Based on published clinical studies and employing efficacy criteria adapted by the Association for Applied Psychophysiology and Biofeedback and the International Society for Neurofeedback and Research, alpha theta training—either alone for alcoholism or in combination with beta training for stimulant and mixed substance abuse and combined with residential treatment programs, is probably efficacious. Considerations of further research design taking these factors into account are discussed and descriptions of contemporary research are given. PMID:18214670
ERIC Educational Resources Information Center
Cooper, Joseph N.; Hall, Jori
2016-01-01
The purpose of this article is to describe how a mixed methods approach was employed to acquire a better understanding of Black male student athletes' experiences at a historically Black college/university in the southeastern United States. A concurrent triangulation design was incorporated to allow different data sources to be collected and…
ERIC Educational Resources Information Center
Usher, Wayne
2011-01-01
Introduction: To identify health website recommendation trends by Gold Coast (Australia) general practitioners (GPs) to their patients. Method: A mixed method approach to data collection and analysis was employed. Quantitative data were collected using a prepaid postal survey, consisting of 17 questions, mailed to 250 (61 per cent) of 410 GPs on…
Fultz, Elissa K; Martin, Douglas L; Hudson, Courtney N; Kippin, Tod E; Szumlinski, Karen K
2017-08-01
A high degree of co-morbidity exists between methamphetamine (MA) addiction and alcohol use disorders and both sequential and simultaneous MA-alcohol mixing increases risk for co-abuse. As little preclinical work has focused on the biobehavioral interactions between MA and alcohol within the context of drug-taking behavior, we employed simple murine models of voluntary oral drug consumption to examine how prior histories of either MA- or alcohol-taking influence the intake of the other drug. In one study, mice with a 10-day history of binge alcohol-drinking [5,10, 20 and 40% (v/v); 2h/day] were trained to self-administer oral MA in an operant-conditioning paradigm (10-40mg/L). In a second study, mice with a 10-day history of limited-access oral MA-drinking (5, 10, 20 and 40mg/L; 2h/day) were presented with alcohol (5-40% v/v; 2h/day) and then a choice between solutions of 20% alcohol, 10mg/L MA or their mix. Under operant-conditioning procedures, alcohol-drinking mice exhibited less MA reinforcement overall, than water controls. However, when drug availability was not behaviorally-contingent, alcohol-drinking mice consumed more MA and exhibited greater preference for the 10mg/L MA solution than drug-naïve and combination drug-experienced mice. Conversely, prior MA-drinking history increased alcohol intake across a range of alcohol concentrations. These exploratory studies indicate the feasibility of employing procedurally simple murine models of sequential and simultaneous oral MA-alcohol mixing of relevance to advancing our biobehavioral understanding of MA-alcohol co-abuse. Copyright © 2017 Elsevier B.V. All rights reserved.
Rat Phantom Depth Dose Studies in Electron, X-ray, Gamma-Ray, and Reactor Radiation Fields
1986-12-01
i©™D©/^ ^1[P@^T Rat phantom depth dose studies in electron , Xrayf gamma-ray, and reactor radiation fields M. Dooley D. M. Eagleson G. H. Zeman...energy electrons , bremsstrahlung, and mixed neutron/gamma radiation fields are sometimes used in radiobiological experiments employing rats. This report...have revealed differing sensitivities of experimental animals that have been exposed to cobalt-60 photons, high-energy electrons , high-energy X rays
Sangwan, P; Kaushik, C P; Garg, V K
2010-01-01
In India, millions of tons of press mud (PM) are generated by sugar mills every year. This paper reports the potential of vermitechnology to convert sugar industry waste PM mixed with cow dung (CD) into vermicompost, employing an epigeic earthworm Eisenia fetida. A total of six different reactors were established having different ratios of PM and CD including one control (CD only). The growth and fecundity of E. fetida was monitored for 13 weeks. Maximum growth was recorded in 100% CD, but earthworms grew and reproduced favourably up to 1:1 PM and CD feed composition. However, greater percentages of PM in different reactors significantly affected the growth and fecundity of worms. Vermicomposting resulted in a decrease in carbon concentration and an increase in nitrogen, phosphorus and calcium concentrations of the vermicompost. Investigations indicated that vermicomposting could be an alternative technology for the management of PM into useful fertilizing material, if mixed at maximum 50% with CD.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Ye; Cabot, William H.; Thornber, Ben
Rayleigh–Taylor instability (RTI) and Richtmyer–Meshkov instability (RMI) are serious practical issues in inertial confinement fusion research, and also have relevance to many cases of astrophysical fluid dynamics. So far, much of the attention has been paid to the late-time scaling of the mixed width, which is used as a surrogate to how well the fluids have been mixed. Yet, the actual amount of mixed mass could be viewed as a more direct indicator on the evolution of the mixing layers due to hydrodynamic instabilities. Despite its importance, there is no systematic study as yet on the scaling of the mixedmore » mass for either the RTI or the RMI induced flow. In this article, the normalized mixed mass (Ψ) is introduced for measuring the efficiency of the mixed mass. Six large numerical simulation databases have been employed: the RTI cases with heavy-to-light fluid density ratios of 1.5, 3, and 9; the single shock RMI cases with density ratios of 3 and 20; and a reshock RMI case with density ratio of 3. Using simulated flow fields, the normalized mixed mass Ψ is shown to be more sensitive in discriminating the variation with Atwood number for the RTI flows. Moreover, Ψ is demonstrated to provide more consistent results for both the RTI and RMI flows when compared with the traditional mixedness parameters, Ξ and Θ.« less
Axisymmetric magnetic modes of neutron stars having mixed poloidal and toroidal magnetic fields
NASA Astrophysics Data System (ADS)
Lee, Umin
2018-05-01
We calculate axisymmetric magnetic modes of a neutron star possessing a mixed poloidal and toroidal magnetic field, where the toroidal field is assumed to be proportional to a dimensionless parameter ζ0. Here, we assume an isentropic structure for the neutron star and consider no effects of rotation. Ignoring the equilibrium deformation due to the magnetic field, we employ a polytrope of the index n = 1 as the background model for our modal analyses. For the mixed poloidal and toroidal magnetic field with ζ _0\
Goldberg, Wendy A; Prause, Joann; Lucas-Thompson, Rachel; Himsel, Amy
2008-01-01
This meta-analysis of 68 studies (770 effect sizes) used random effects models to examine whether children's achievement differed depending on whether their mothers were employed. Four achievement outcomes were emphasized: formal tests of achievement and intellectual functioning, grades, and teacher ratings of cognitive competence. When all employment was compared with nonemployment for combined and separate achievement outcomes without moderators, effects were nonsignificant. Small beneficial effects of part-time compared with full-time employment were apparent for all achievement outcomes combined and for each individual achievement outcome. Significant sample-level moderators of the associations between maternal employment and achievement for all outcomes combined included family structure, race/ethnicity, and socioeconomic status; associations were positive when samples were majority 1-parent families and mixed 1- and 2-parent families, racially/ethnically diverse or international in composition, and not middle-upper class. Analyses of child gender indicated more positive effects for girls. Children's age was a significant moderator for the outcome of intellectual functioning. The identification of sample-level moderators of the relationship between maternal employment and children's achievement highlights the importance of social context in understanding work-family linkages. Copyright (c) 2008 APA.
Wang, Ke-Sheng; Liu, Xuefeng; Ategbole, Muyiwa; Xie, Xin; Liu, Ying; Xu, Chun; Xie, Changchun; Sha, Zhanxin
2017-01-01
Objective: Screening for colorectal cancer (CRC) can reduce disease incidence, morbidity, and mortality. However, few studies have investigated the urban-rural differences in social and behavioral factors influencing CRC screening. The objective of the study was to investigate the potential factors across urban-rural groups on the usage of CRC screening. Methods: A total of 38,505 adults (aged ≥40 years) were selected from the 2009 California Health Interview Survey (CHIS) data - the latest CHIS data on CRC screening. The weighted generalized linear mixed-model (WGLIMM) was used to deal with this hierarchical structure data. Weighted simple and multiple mixed logistic regression analyses in SAS ver. 9.4 were used to obtain the odds ratios (ORs) and their 95% confidence intervals (CIs). Results: The overall prevalence of CRC screening was 48.1% while the prevalence in four residence groups - urban, second city, suburban, and town/rural, were 45.8%, 46.9%, 53.7% and 50.1%, respectively. The results of WGLIMM analysis showed that there was residence effect (p<0.0001) and residence groups had significant interactions with gender, age group, education level, and employment status (p<0.05). Multiple logistic regression analysis revealed that age, race, marital status, education level, employment stats, binge drinking, and smoking status were associated with CRC screening (p<0.05). Stratified by residence regions, age and poverty level showed associations with CRC screening in all four residence groups. Education level was positively associated with CRC screening in second city and suburban. Infrequent binge drinking was associated with CRC screening in urban and suburban; while current smoking was a protective factor in urban and town/rural groups. Conclusions: Mixed models are useful to deal with the clustered survey data. Social factors and behavioral factors (binge drinking and smoking) were associated with CRC screening and the associations were affected by living areas such as urban and rural regions. PMID:28952708
Beidas, Rinad S; Wolk, Courtney L Benjamin; Walsh, Lucia M; Evans, Arthur C; Hurford, Matthew O; Barg, Frances K
2014-11-23
Organizational factors impact the delivery of mental health services in community settings. Mixed-methods analytic approaches have been recommended, though little research within implementation science has explicitly compared inductive and deductive perspectives to understand their relative value in understanding the same constructs. The purpose of our study is to use two different paradigmatic approaches to deepen our understanding of organizational social context. We accomplish this by using a mixed-methods approach in an investigation of organizational social context in community mental health clinics. Nineteen agencies, representing 23 sites, participated. Enrolled participants included 130 therapists, 36 supervisors, and 22 executive administrators. Quantitative data was obtained via the Organizational Social Context (OSC) measure. Qualitative data, comprised of direct observation with spot sampling generated from agency visits, was coded using content analysis and grounded theory. The present study examined elements of organizational social context that would have been missed if only quantitative data had been obtained and utilized mixed methods to investigate if stratifying observations based on quantitative ratings from the OSC resulted in the emergence of differential themes. Four of the six OSC constructs were commonly observed in field observations (i.e., proficiency, rigidity, functionality, stress), while the remaining two constructs were not frequently observed (i.e., resistance, engagement). Constructs emerged related to organizational social context that may have been missed if only quantitative measurement was employed, including those around the physical environment, commentary about evidence-based practice initiatives, leadership, cultural diversity, distrust, and affect. Stratifying agencies by "best," "average," and "worst" organizational social context impacted interpretation for three constructs (affect, stress, and leadership). Results support the additive value of integrating inductive and deductive perspectives in implementation science research. This synthesis of approaches facilitated a more comprehensive understanding and interpretation of the findings than would have been possible if either methodology had been employed in isolation.
Wang, Ke-Sheng; Liu, Xuefeng; Ategbole, Muyiwa; Xie, Xin; Liu, Ying; Xu, Chun; Xie, Changchun; Sha, Zhanxin
2017-09-27
Objective: Screening for colorectal cancer (CRC) can reduce disease incidence, morbidity, and mortality. However, few studies have investigated the urban-rural differences in social and behavioral factors influencing CRC screening. The objective of the study was to investigate the potential factors across urban-rural groups on the usage of CRC screening. Methods: A total of 38,505 adults (aged ≥40 years) were selected from the 2009 California Health Interview Survey (CHIS) data - the latest CHIS data on CRC screening. The weighted generalized linear mixed-model (WGLIMM) was used to deal with this hierarchical structure data. Weighted simple and multiple mixed logistic regression analyses in SAS ver. 9.4 were used to obtain the odds ratios (ORs) and their 95% confidence intervals (CIs). Results: The overall prevalence of CRC screening was 48.1% while the prevalence in four residence groups - urban, second city, suburban, and town/rural, were 45.8%, 46.9%, 53.7% and 50.1%, respectively. The results of WGLIMM analysis showed that there was residence effect (p<0.0001) and residence groups had significant interactions with gender, age group, education level, and employment status (p<0.05). Multiple logistic regression analysis revealed that age, race, marital status, education level, employment stats, binge drinking, and smoking status were associated with CRC screening (p<0.05). Stratified by residence regions, age and poverty level showed associations with CRC screening in all four residence groups. Education level was positively associated with CRC screening in second city and suburban. Infrequent binge drinking was associated with CRC screening in urban and suburban; while current smoking was a protective factor in urban and town/rural groups. Conclusions: Mixed models are useful to deal with the clustered survey data. Social factors and behavioral factors (binge drinking and smoking) were associated with CRC screening and the associations were affected by living areas such as urban and rural regions. Creative Commons Attribution License
Regmi, Krishna
2018-01-01
Although considerable attention has been paid to the use of quantitative methods in health research, there has been limited focus on decentralisation research using a qualitative-driven mixed method design. Decentralisation presents both a problematic concept and methodological challenges, and is more context-specific and is often multi-dimensional. Researchers often consider using more than one method design when researching phenomena is complex in nature. Aim To explore the effects of decentralisation on the provision of primary healthcare services. Qualitative-driven mixed method design, employing three methods of data collections: focus group discussions (FGDs), semi-structured interviews (SSIs) and participant observations under two components, that is, core component and supplementary components were used. Four FGDs with health service practitioners, three FGDs with district stakeholders, 20 SSIs with health service users and 20 SSIs with national stakeholders were carried out. These were conducted sequentially. NVivo10, a data management program, was utilised to code the field data, employing a content analysis method for searching the underlying themes or concepts in the text material. Findings Both positive and negative experiences related to access, quality, planning, supplies, coordination and supervision were identified. This study suggests some evidence of the effects of decentralisation on health outcomes in general, as well as filling a gap of understanding and examining healthcare through a qualitative-driven mixed methods approach, in particular. Future research in the area of qualitative in-depth understanding of the problems (why decentralisation, why now and what for) would provoke an important data set that benefits the researchers and policy-makers for planning and implementing effective health services.
Advancing student nurse knowledge of the biomedical sciences: A mixed methods study.
Craft, Judy; Christensen, Martin; Bakon, Shannon; Wirihana, Lisa
2017-01-01
Nursing students' ability to learn, integrate and apply bioscience knowledge to their clinical practice remains a concern. To evaluate the implementation, influence, and student perspective of a team-teaching workshop to integrate bioscience theory with clinical nursing practice. The team-teaching workshop was offered prior to commencement of the university semester as a refresher course at an Australian university. This study employed a sequential explanatory mixed methods design incorporating both quantitative and qualitative items. An evaluation survey with quantitative and qualitative items and a focus group were employed. The qualitative data were analysed using a thematic approach. The quantitative data was combined with the emergent themes in the qualitative data. Participants were final year nursing students. Nine students attended the workshop. All students completed the evaluation (N=9) and 44.4% (N=4) attended the focus group. The results revealed six themes: (1) lectures are an inadequate teaching strategy for bioscience; (2) teaching strategies which incorporate active learning engage students; (3) the team-teaching workshop provides an effective learning environment; (4) the workshop content should be expanded; (5) pharmacology should relate to bioscience, and bioscience should relate to nursing; and (6) team-teaching was effective in integrating pharmacology with bioscience, and then translating this into nursing practice. Students had felt there was disjointedness between pharmacology and bioscience, and between bioscience and nursing care within their undergraduate studies. The workshop that was based on team-teaching bridged those gaps, utilised active learning strategies and provided an effective learning environment. Team-teaching that employs active learning strategies is an effective approach to assist nursing students to integrate bioscience knowledge into their nursing practice. Copyright © 2016 Elsevier Ltd. All rights reserved.
Corrigan, Patrick W.; Tsang, Hector W. H.; Shi, Kan; Lam, Chow S.; Larson, Jon
2010-01-01
Work opportunities for people with behaviorally driven health conditions such as HIV/AIDS, drug abuse, alcohol abuse, and psychosis are directly impacted by employer perspectives. To investigate this issue, we report findings from a mixed method design involving qualitative interviews followed by a quantitative survey of employers from Chicago (U.S.), Beijing (China), and Hong Kong (China). Findings from qualitative interviews of 100 employers were used to create 27 items measuring employer perspectives (the Employer Perspective Scale: EPS) about hiring people with health conditions. These perspectives reflect reasons for or against discrimination. In the quantitative phase of the study, representative samples of approximately 300 employers per city were administered the EPS in addition to measures of stigma, including attributions about disease onset and offset. The EPS and stigma scales were completed in the context of one of five randomly assigned health conditions. We weighted data with ratios of key demographics between the sample and the corresponding employer population data. Analyses showed that both onset and offset responsibility varied by behaviorally driven condition. Analyses also showed that employer perspectives were more negative for health conditions that are seen as more behaviorally driven, e.g., drug and alcohol abuse. Chicago employers endorsed onset and offset attributions less strongly compared to those in Hong Kong and Beijing. Chicago employers also recognized more benefits of hiring people with various health conditions. The implications of these findings for better understanding stigma and stigma change among employers are considered. PMID:21036445
Quasi-Static Viscoelastic Finite Element Model of an Aircraft Tire
NASA Technical Reports Server (NTRS)
Johnson, Arthur R.; Tanner, John A.; Mason, Angela J.
1999-01-01
An elastic large displacement thick-shell mixed finite element is modified to allow for the calculation of viscoelastic stresses. Internal strain variables are introduced at the element's stress nodes and are employed to construct a viscous material model. First order ordinary differential equations relate the internal strain variables to the corresponding elastic strains at the stress nodes. The viscous stresses are computed from the internal strain variables using viscous moduli which are a fraction of the elastic moduli. The energy dissipated by the action of the viscous stresses is included in the mixed variational functional. The nonlinear quasi-static viscous equilibrium equations are then obtained. Previously developed Taylor expansions of the nonlinear elastic equilibrium equations are modified to include the viscous terms. A predictor-corrector time marching solution algorithm is employed to solve the algebraic-differential equations. The viscous shell element is employed to computationally simulate a stair-step loading and unloading of an aircraft tire in contact with a frictionless surface.
Significance of the model considering mixed grain-size for inverse analysis of turbidites
NASA Astrophysics Data System (ADS)
Nakao, K.; Naruse, H.; Tokuhashi, S., Sr.
2016-12-01
A method for inverse analysis of turbidity currents is proposed for application to field observations. Estimation of initial condition of the catastrophic events from field observations has been important for sedimentological researches. For instance, there are various inverse analyses to estimate hydraulic conditions from topography observations of pyroclastic flows (Rossano et al., 1996), real-time monitored debris-flow events (Fraccarollo and Papa, 2000), tsunami deposits (Jaffe and Gelfenbaum, 2007) and ancient turbidites (Falcini et al., 2009). These inverse analyses need forward models and the most turbidity current models employ uniform grain-size particles. The turbidity currents, however, are the best characterized by variation of grain-size distribution. Though there are numerical models of mixed grain-sized particles, the models have difficulty in feasibility of application to natural examples because of calculating costs (Lesshaft et al., 2011). Here we expand the turbidity current model based on the non-steady 1D shallow-water equation at low calculation costs for mixed grain-size particles and applied the model to the inverse analysis. In this study, we compared two forward models considering uniform and mixed grain-size particles respectively. We adopted inverse analysis based on the Simplex method that optimizes the initial conditions (thickness, depth-averaged velocity and depth-averaged volumetric concentration of a turbidity current) with multi-point start and employed the result of the forward model [h: 2.0 m, U: 5.0 m/s, C: 0.01%] as reference data. The result shows that inverse analysis using the mixed grain-size model found the known initial condition of reference data even if the condition where the optimization started is deviated from the true solution, whereas the inverse analysis using the uniform grain-size model requires the condition in which the starting parameters for optimization must be in quite narrow range near the solution. The uniform grain-size model often reaches to local optimum condition that is significantly different from true solution. In conclusion, we propose a method of optimization based on the model considering mixed grain-size particles, and show its application to examples of turbidites in the Kiyosumi Formation, Boso Peninsula, Japan.
A study of education and KSAOs on career entry for product engineers: What employers really want
NASA Astrophysics Data System (ADS)
Thornburgh, James
The purpose of the study was to investigate the ways that employers of product engineers evaluate potential employees' job readiness, and which theories related to the education-work transaction are supported by practice. This study used a mixed methods approach and consisted of a state-wide survey (N=106) and local interviews (N=8). The results of the research indicate that attributes of both the Theory of Individual Differences and Credentialing Theory are present in the hiring practices of product engineers. Consistent with the Theory of Individual Differences, employers indicate they look for evidence of various job-related Knowledge, Skills, Abilities, and Other attributes (KSAOs) and they indicate they are willing to hire applicants who have less than a bachelor's degree. Consistent with Credentialing Theory, employers advertise a formal education minimum which represents only one way that individuals may learn to be an engineer. This study also confirmed prior research that most employers use primarily non-evidence based predictors to evaluate applicants. The primary initial screening predictors were experience, GPA, and major, while the primary finalist selection predictors were unstructured interviews, and applications, followed by structured interviews, job knowledge tests, and work sample test. Contrary to previous findings, this study did not find any major differences between what HR professionals, engineering managers, or other manager look for in terms of qualifications or what predictors they use when evaluating applicants for product engineer positions.
Stewart D. Allen; Julie Schaefers
1998-01-01
This assessment focuses on the regional and community economies of southeast Alaska. A mixed economy composed of subsistence harvest and cash income characterizes the economies of most of the regionâs rural communities. Although the share of natural resource-based sectors relative to total employment has remained fairly consistent over the past 10 years, the mix of...
Blended Homing Guidance Law Using Fuzzy Logic
1998-01-01
President, Associate Fellow AIAA + Research Scientist Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection...mixed-strategy guidance strategies discussed in References 3 and 4. According to that research , mixed strategy guidance strategies are found to be...for an advanced missile is the focus of present paper. The present research employs the missile Copyright 1998 by Optimal Synthesis Inc. All Rights
1984-04-13
and Lipetsk and Tambov oblasts. It is necessary to better utilize peat for fer- tilizers and litter , to apply phosphorite and gypsum in a high...concentrates. Equipment was inadequately cleaned in shifting to production of feed formula- tions for broilers following preparation of feed mix...not prepare prestarter mixes for 1 to 4-day broilers . The author of this article was employed for many years in the Ptitseprom system and recalls
ERIC Educational Resources Information Center
Roe, Katie; McConney, Andrew; Mansfield, Caroline F.
2014-01-01
Modern zoos utilise a variety of education tools for communicating with visitors. Previous research has discussed the benefits of providing multiple education communications, yet little research provides an indication of what communications are being employed within zoos today. This research is a two-phased, mixed-methods investigation into the…
Lu, Tao
2017-01-01
The joint modeling of mean and variance for longitudinal data is an active research area. This type of model has the advantage of accounting for heteroscedasticity commonly observed in between and within subject variations. Most of researches focus on improving the estimating efficiency but ignore many data features frequently encountered in practice. In this article, we develop a mixed-effects location scale joint model that concurrently accounts for longitudinal data with multiple features. Specifically, our joint model handles heterogeneity, skewness, limit of detection, measurement errors in covariates which are typically observed in the collection of longitudinal data from many studies. We employ a Bayesian approach for making inference on the joint model. The proposed model and method are applied to an AIDS study. Simulation studies are performed to assess the performance of the proposed method. Alternative models under different conditions are compared.
Jonathan D. Carlisle; Wayne A. Geyer; J. W. Van Sambeek
2003-01-01
Effective weed control in young deciduous plantations is often prescribed to enhance survivability and growth (Bey and others 1975). Chemical weed control often employs broadcast, strip, and spot applications that markedly affect the ground surface area treated. Our study investigates the effect of four levels of treated surface area of a tank mix of glyphosate and...
Mistry, Rashmita S; White, Elizabeth S; Chow, Kirby A; Griffin, Katherine M; Nenadal, Lindsey
2016-01-01
Mixed methods research approaches are gaining traction across various social science disciplines, including among developmental scientists. In this chapter, we discuss the utility of a mixed methods research approach in examining issues related to equity and justice. We incorporate a brief overview of quantitative and qualitative monomethod research approaches in our larger discussion of the advantages, procedures, and considerations of employing a mixed methods design to advance developmental science from an equity and justice perspective. To better illustrate the theoretical and practical significance of a mixed methods research approach, we include examples of research conducted on children and adolescents' conceptions of economic inequality as one example of developmental science research with an equity and justice frame. © 2016 Elsevier Inc. All rights reserved.
The Apollo 16 regolith - A petrographically-constrained chemical mixing model
NASA Technical Reports Server (NTRS)
Kempa, M. J.; Papike, J. J.; White, C.
1980-01-01
A mixing model for Apollo 16 regolith samples has been developed, which differs from other A-16 mixing models in that it is both petrographically constrained and statistically sound. The model was developed using three components representative of rock types present at the A-16 site, plus a representative mare basalt. A linear least-squares fitting program employing the chi-squared test and sum of components was used to determine goodness of fit. Results for surface soils indicate that either there are no significant differences between Cayley and Descartes material at the A-16 site or, if differences do exist, they have been obscured by meteoritic reworking and mixing of the lithologies.
Ervasti, Jenni; Vahtera, Jussi; Virtanen, Pekka; Pentti, Jaana; Oksanen, Tuula; Ahola, Kirsi; Kivimäki, Mika; Virtanen, Marianna
2014-07-01
Research on temporary employment as a risk factor for work disability due to depression is mixed, and few studies have measured work disability outcome in detail. We separately examined the associations of temporary employment with (i) the onset of work disability due to depression, (ii) the length of disability episodes, and (iii) the recurrence of work disability, taking into account the possible effect modification of sociodemographic factors. We linked the prospective cohort study data of 107 828 Finnish public sector employees to national registers on work disability (>9 days) due to depression from January 2005 to December 2011. Disability episodes were longer among temporary than permanent employees after adjustment for age, sex, level of education, chronic somatic disease, and history of mental/behavioral disorders [cumulative odds ratio (COR) 1.37, 95% confidence interval (95% CI) 1.25-51). The association between temporary employment and the length of depression-related disability episodes was more pronounced among participants with a low educational level (COR 1.95, 95% CI 1.54-2.48) and older employees (>52 years; COR 3.67, 95% CI 2.83-4.76). The association was weaker in a subgroup of employees employed for ≥ 50% of the follow-up period (95% of the original sample). Temporary employment was not associated with the onset or recurrence of depression-related work disability. Temporary employment is associated with slower return to work, indicated by longer depression-related disability episodes, especially among older workers and those with a low level of education. Continuous employment might protect temporary employees from prolonged work disability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Mao; Qiu, Zihua; Liang, Chunlei
In the present study, a new spectral difference (SD) method is developed for viscous flows on meshes with a mixture of triangular and quadrilateral elements. The standard SD method for triangular elements, which employs Lagrangian interpolating functions for fluxes, is not stable when the designed accuracy of spatial discretization is third-order or higher. Unlike the standard SD method, the method examined here uses vector interpolating functions in the Raviart-Thomas (RT) spaces to construct continuous flux functions on reference elements. Studies have been performed for 2D wave equation and Euler equa- tions. Our present results demonstrated that the SDRT method ismore » stable and high-order accurate for a number of test problems by using triangular-, quadrilateral-, and mixed- element meshes.« less
A study of reacting free and ducted hydrogen/air jets
NASA Technical Reports Server (NTRS)
Beach, H. L., Jr.
1975-01-01
The mixing and reaction of a supersonic jet of hydrogen in coaxial free and ducted high temperature test gases were investigated. The importance of chemical kinetics on computed results, and the utilization of free-jet theoretical approaches to compute enclosed flow fields were studied. Measured pitot pressure profiles were correlated by use of a parabolic mixing analysis employing an eddy viscosity model. All computations, including free, ducted, reacting, and nonreacting cases, use the same value of the empirical constant in the viscosity model. Equilibrium and finite rate chemistry models were utilized. The finite rate assumption allowed prediction of observed ignition delay, but the equilibrium model gave the best correlations downstream from the ignition location. Ducted calculations were made with finite rate chemistry; correlations were, in general, as good as the free-jet results until problems with the boundary conditions were encountered.
ERIC Educational Resources Information Center
Frazier, Andrea P.
2012-01-01
This research study employed a mixed method sequential approach and investigated the number of Schools of Medicine within the United States that offer health literacy as a component of their curriculum and a course of study within the academic setting. Data were gathered from medical school surveys and personal interviews. Curriculum content,…
Johannessen, Gudrun; Eikeland, Anne; Stubberud, Dag-Gunnar; Fagerstöm, Lisbeth
2011-10-01
The aim of this study was to describe patient satisfaction with nursing care in three different Norwegian Coronary Intensive Care Units and compare the results with other structural factors such as nursing competence, skill-mix, clinical experience, nurse to patient ratio and number of beds. A descriptive and comparative design was employed and 150 patients at three Coronary Intensive Care Units were included. Patient satisfaction data was collected using the Intensive Nursing Care Quality Instrument (59 items). The data collected was comprised of two parts: a questionnaire and information on the structural factors of the organisational structure. The data was analysed using descriptive statistics. Patients expressed overall satisfaction with the nursing care. No clear association was found between patient satisfaction and nursing competence, skill-mix, clinical experience, nurse to patient ratio and number of beds. When comparing results between units, significant differences were seen for 17 out of 46 questions. The results provide insight into how critical care staffing and skill-mix affect patient satisfaction and guide future nursing research in this subject area. Copyright © 2011. Published by Elsevier Ltd.
Valorisation of food and beverage waste via saccharification for sugars recovery.
Kwan, Tsz Him; Ong, Khai Lun; Haque, Md Ariful; Kwan, Wing Hei; Kulkarni, Sandeep; Lin, Carol Sze Ki
2018-05-01
Valorisation of mixed food and beverage (F&B) waste was studied for the recovery of sugars via saccharification. Glucoamylase and sucrase were employed to hydrolyse the starch and sucrose present in the mixed F&B waste because of the high cost-effectiveness for such recovery. The Michaelis-Menten kinetics model suggests that preservatives and additives in beverages did not inhibit glucoamylase and sucrase during saccharification. High levels of glucose (228.1 g L -1 ) and fructose (55.7 g L -1 ) were efficiently produced within 12 h at a solid-to-liquid ratio of 37.5% (w/v) in 2.5 L bioreactors. An overall conversion yield of 0.17 g sugars per g of mixed F&B waste was obtained in mass balance analysis. Lastly, possible industrial applications of the sugar-rich hydrolysate and by-products are discussed. This study is believed to cast insights into F&B waste recycling via biotechnology to produce high-value added products to promote the establishment of a circular bio-economy. Copyright © 2018 Elsevier Ltd. All rights reserved.
Sulmonetti, Taylor P.; Hu, Bo; Lee, Sungsik; ...
2017-08-08
In this study, the ring-opening of furfuryl alcohol to diol products, including 1,2-pentanediol and 1,5- pentanediol, is investigated over reduced Cu-Co-Al mixed metal oxides in a liquid phase batch reactor under H 2 pressure. These catalysts are synthesized through the calcination of layered double hydroxides (LDH) to yield well-dispersed, porous mixed metal oxides, which upon reduction displayed activity towards diols, mainly the valuable monomer 1,5-pentanediol. The addition of Cu facilitated the reduction of Co oxide species at lower temperatures, and under optimized conditions a yield towards 1,5-pentanediol of 44% (total diol yield of 62%) was achieved. Various characterization techniques includingmore » TPR, XPS, and XAS are employed to elucidate the structure of the catalysts, suggesting the formation of both metallic (Co and Cu) and oxide (CoO) species after reduction and passivation. Finally, this study demonstrates the promising characteristics that non-precious multi-metal catalysts have for the conversion of biomass derived platform molecules to plastic precursors« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sulmonetti, Taylor P.; Hu, Bo; Lee, Sungsik
In this study, the ring-opening of furfuryl alcohol to diol products, including 1,2-pentanediol and 1,5- pentanediol, is investigated over reduced Cu-Co-Al mixed metal oxides in a liquid phase batch reactor under H 2 pressure. These catalysts are synthesized through the calcination of layered double hydroxides (LDH) to yield well-dispersed, porous mixed metal oxides, which upon reduction displayed activity towards diols, mainly the valuable monomer 1,5-pentanediol. The addition of Cu facilitated the reduction of Co oxide species at lower temperatures, and under optimized conditions a yield towards 1,5-pentanediol of 44% (total diol yield of 62%) was achieved. Various characterization techniques includingmore » TPR, XPS, and XAS are employed to elucidate the structure of the catalysts, suggesting the formation of both metallic (Co and Cu) and oxide (CoO) species after reduction and passivation. Finally, this study demonstrates the promising characteristics that non-precious multi-metal catalysts have for the conversion of biomass derived platform molecules to plastic precursors« less
Buunaaisie, C; Manyara, A M; Annett, H; Bird, E L; Bray, I; Ige, J; Jones, M; Orme, J; Pilkington, P; Evans, D
2018-05-08
This article aims to describe the public health career experiences of international graduates of a Master of Science in Public Health (MSc PH) programme and to contribute to developing the evidence base on international public health workforce capacity development. A sequential mixed methods study was conducted between January 2017 and April 2017. Ninety-seven international graduates of one UK university's MSc PH programme were invited to take part in an online survey followed by semistructured interviews, for respondents who consented to be interviewed. We computed the descriptive statistics of the quantitative data obtained, and qualitative data were thematically analysed. The response rate was 48.5%. Most respondents (63%) were employed by various agencies within 1 year after graduation. Others (15%) were at different stages of doctor of philosophy studies. Respondents reported enhanced roles after graduation in areas such as public health policy analysis (74%); planning, implementation and evaluation of public health interventions (74%); leadership roles (72%); and research (70%). The common perceived skills that were relevant to the respondents' present jobs were critical analysis (87%), multidisciplinary thinking (86%), demonstrating public health leadership skills (84%) and research (77%). Almost all respondents (90%) were confident in conducting research. Respondents recommended the provision of longer public health placement opportunities, elective courses on project management and advanced statistics, and 'internationalisation' of the programme's curriculum. The study has revealed the relevance of higher education in public health in developing the career prospects and skills of graduates. International graduates of this MSc PH programme were satisfied with the relevance and impact of the skills they acquired during their studies. The outcomes of this study can be used for curriculum reformation. Employers' perspectives of the capabilities of these graduates, however, need further consideration. Copyright © 2018 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.
Davis, M A; Freeman, J W; Kirby, E C
1998-01-01
OBJECTIVE: To examine the effect of case mix-adjusted reimbursement policy and market factors on nursing home performance. DATA SOURCES AND STUDY SETTING: Data from Medicaid certification inspection surveys, Medicaid cost reports, and the Kentucky State Center for Health Statistics for the years 1989 and 1991, to examine changes in nursing home performance stemming from the adoption of case mix-adjusted reimbursement in 1990. STUDY DESIGN: In addition to cross-sectional regressions, a first-difference approach to fixed-effects regression analyses was employed to control for facility differences that were essentially fixed during the survey years and to estimate the effects of time-varying predictors on changes in facility expenditures, efficiency, and profitability. PRINCIPAL FINDINGS: Facilities that increased the proportion of Medicaid residents and eliminated excess capacity experienced higher profitability gains during the beginning phase of case-mix reimbursement. Having a heavy-care resident population was positively related to expenditures prior to reimbursement reform, and it was negatively related to expenditures after the case-mix reimbursement policy was introduced. While facility-level changes in case mix had no reliable influence on costs or profits, nursing homes showing an increased prevalence of poor-quality nursing practices exhibited increases in efficiency and profitability. At the market level, reductions in excess or empty nursing home beds were accompanied by a significant growth in home health services. Moreover, nursing homes located in markets with expanding home health services exhibited higher increases in costs per case-mix unit. CONCLUSIONS: Characteristics of the reimbursement system appear to reward a cost minimization orientation with potentially detrimental effects on quality of care. These effects, exacerbated by a supply-constrained market, may be mitigated by policies that encourage the expansion of home health service availability. PMID:9776938
Wang, Yan Jason; Yang, Bo; Lipsky, Eric M; Robinson, Allen L; Zhang, K Max
2013-01-15
Experimental results from laboratory emission testing have indicated that particulate emission measurements are sensitive to the dilution process of exhaust using fabricated dilution systems. In this paper, we first categorize the dilution parameters into two groups: (1) aerodynamics (e.g., mixing types, mixing enhancers, dilution ratios, residence time); and (2) mixture properties (e.g., temperature, relative humidity, particle size distributions of both raw exhaust and dilution gas). Then we employ the Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model to investigate the effects of those parameters on a set of particulate emission measurements comparing two dilution tunnels, i.e., a T-mixing lab dilution tunnel and a portable field dilution tunnel with a type of coaxial mixing. The turbulent flow fields and aerosol dynamics of particles are simulated inside two dilution tunnels. Particle size distributions under various dilution conditions predicted by CTAG are evaluated against the experimental data. It is found that in the area adjacent to the injection of exhaust, turbulence plays a crucial role in mixing the exhaust with the dilution air, and the strength of nucleation dominates the level of particle number concentrations. Further downstream, nucleation terminates and the growth of particles by condensation and coagulation continues. Sensitivity studies reveal that a potential unifying parameter for aerodynamics, i.e., the dilution rate of exhaust, plays an important role in new particle formation. The T-mixing lab tunnel tends to favor the nucleation due to a larger dilution rate of the exhaust than the coaxial mixing field tunnel. Our study indicates that numerical simulation tools can be potentially utilized to develop strategies to reduce the uncertainties associated with dilution samplings of emission sources.
Requirements of shrimp, Penaeus chinensis O'sbeck for potassium, sodium, magnesium and iodine
NASA Astrophysics Data System (ADS)
Liu, Fa-Yi; Li, He-Fang; Wang, Hui-Liang; Liang, De-Hai; Tian, Yu-Chuan
1995-06-01
Potassium, sodium, magnesium and iodine requirements of shrimp, Penaeus chinensis were studied. Orthogonal design was employed in this experiment. The composition of the basal diet consisted of fish meal, peanut cake, corn meal, soybean cake, wheat bran, vitamin mix and mineral mix, and supplementations of potassium, sodium, magnesium and iodine in the basal diet were made according to the L9(34) orthogonal table. The results indicated that iodine supplementation improved growth of the shrimp significantly and raised survival very significantly, iodine requirement of the shrimp was 0.003%; sodium requirement was 0.87% or less; and that 1.1 1.3% potassium and 0.18 0.38% magnesium in the diet were proper nutrition supplements for the shrimp.
NASA Astrophysics Data System (ADS)
Kuć, Marta; Cieślik-Boczula, Katarzyna; Rospenk, Maria
2018-06-01
The influence of cholesterol on the structure of the model lipid bilayers treated with inhalation anesthetics (enflurane, isoflurane, sevoflurane and halothane) was investigated employing near-infrared (NIR) spectroscopy combined with the Principal Component Analysis (PCA). The conformational changes occurring in the hydrophobic area of the lipid bilayers were analyzed using the first overtones of symmetric (2νs) and antisymmetric (2νas) stretching vibrations of the CH2 groups of lipid aliphatic chains. The temperature values of chain-melting phase transition (Tm) of anesthetic-mixed dipalmitoylphosphatidylcholine (DPPC)/cholesterol and dipalmitoylphosphatidylglycerol (DPPG)/cholesterol membranes, which were obtained from the PCA analysis, were compared with cholesterol-free DPPC and DPPG bilayers mixed with inhalation anesthetics.
Effect of diastolic flow patterns on the function of the left ventricle
NASA Astrophysics Data System (ADS)
Seo, Jung Hee; Mittal, Rajat
2013-11-01
Direct numerical simulations are used to study the effect of intraventricular flow patterns on the pumping efficiency and the blood mixing and transport characteristics of the left ventricle. The simulations employ a geometric model of the left ventricle which is derived from contrast computed tomography. A variety of diastolic flow conditions are generated for a fixed ejection fraction in order to delineate the effect of flow patterns on ventricular performance. The simulations indicate that the effect of intraventricular blood flow pattern on the pumping power is physiologically insignificant. However, diastolic flow patterns have a noticeable effect on the blood mixing as well as the residence time of blood cells in the ventricle. The implications of these findings on ventricular function are discussed.
The role of promotion in alcoholism treatment marketing.
Jones, M A; Self, D R; Owens, C A; Kline, T A
1988-01-01
This article is an overview of the promotion function as a part of the ATM's marketing mix. It approaches various promotion decision areas from a managerial perspective, focusing upon some key components of promotion planning. Rather than provide specific operational or implementation details (how to write a brochure) it is more conceptual in nature and offers a framework for promotion planners. The article addresses promotion management, promotion objectives, analysis for promotion planning, the promotion mix, and addresses the benefits and limitations of some specific promotion tools available to the ATM manager. It treats ATMs as a service and reveals specific implications for promotion strategy dictated by services. The article also reports promotion tools employed by Alabama ATMs citing data from the Alabama study.
Mixed infections in tuberculosis: The missing part in a puzzle.
Tarashi, Samira; Fateh, Abolfazl; Mirsaeidi, Mehdi; Siadat, Seyed Davar; Vaziri, Farzam
2017-12-01
The mixed strains infection phenomenon is a major problem posing serious challenges in control of tuberculosis (TB). In patients with mixed infection, several different strains of Mycobacterium tuberculosis can be isolated simultaneously. Although different genotyping methods and various molecular approaches can be employed for detection of mixed infection in clinical samples, the MIRU-VNTR technique is more sensitive with higher discriminative power than many widely used techniques. Furthermore, the recent introduction of whole genome sequencing (WGS) promises to reveal more details about mixed infection with high resolution. WGS has been used for detection of mixed infection with high sensitivity and discriminatory, but the technology is currently limited to developed countries. Mixed infection may involve strains with different susceptibility patterns, which may alter the treatment outcome. In this report, we review the current concepts of mixed strains infection and also infection involving strains with a different susceptibility pattern in TB. We evaluate the importance of identifying mixed infection for diagnosis as well as treatment and highlight the accuracy and clinical utility of direct genotyping of clinical specimens. Copyright © 2017 Elsevier Ltd. All rights reserved.
CFD simulation of gas and non-Newtonian fluid two-phase flow in anaerobic digesters.
Wu, Binxin
2010-07-01
This paper presents an Eulerian multiphase flow model that characterizes gas mixing in anaerobic digesters. In the model development, liquid manure is assumed to be water or a non-Newtonian fluid that is dependent on total solids (TS) concentration. To establish the appropriate models for different TS levels, twelve turbulence models are evaluated by comparing the frictional pressure drops of gas and non-Newtonian fluid two-phase flow in a horizontal pipe obtained from computational fluid dynamics (CFD) with those from a correlation analysis. The commercial CFD software, Fluent12.0, is employed to simulate the multiphase flow in the digesters. The simulation results in a small-sized digester are validated against the experimental data from literature. Comparison of two gas mixing designs in a medium-sized digester demonstrates that mixing intensity is insensitive to the TS in confined gas mixing, whereas there are significant decreases with increases of TS in unconfined gas mixing. Moreover, comparison of three mixing methods indicates that gas mixing is more efficient than mixing by pumped circulation while it is less efficient than mechanical mixing.
Cluff, Laurie A; Lang, Jason E; Rineer, Jennifer R; Jones-Jack, Nkenge H; Strazza, Karen M
2018-05-01
Centers for Disease Control and Prevention (CDC) initiated the Work@Health Program to teach employers how to improve worker health using evidence-based strategies. Program goals included (1) determining the best way(s) to deliver employer training, (2) increasing employers' knowledge of workplace health promotion (WHP), and (3) increasing the number of evidence-based WHP interventions at employers' worksites. This study is one of the few to examine the effectiveness of a program designed to train employers how to implement WHP programs. Pre- and posttest design. Training via 1 of 3 formats hands-on, online, or blended. Two hundred six individual participants from 173 employers of all sizes. Eight-module training curriculum to guide participants through building an evidence-based WHP program, followed by 6 to 10 months of technical assistance. The CDC Worksite Health ScoreCard and knowledge, attitudes, and behavior survey. Descriptive statistics, paired t tests, and mixed linear models. Participants' posttraining mean knowledge scores were significantly greater than the pretraining scores (61.1 vs 53.2, P < .001). A year after training, employers had significantly increased the number of evidence-based interventions in place (47.7 vs 35.5, P < .001). Employers' improvements did not significantly differ among the 3 training delivery formats. The Work@Health Program provided employers with knowledge to implement WHP interventions. The training and technical assistance provided structure, practical guidance, and tools to assess needs and select, implement, and evaluate interventions.
Thavamani, Palanisami; Malik, Seidu; Beer, Michael; Megharaj, Mallavarapu; Naidu, Ravi
2012-05-30
The co-occurrence of polyaromatic hydrocarbons (PAHs) with heavy metals and their effect on soil microbial activity have not been systematically investigated. In this study a holistic approach was employed by combining physico-chemical, biological and advanced molecular methods to determine the soil microbial activities of long-term mixed contaminated soils collected from a former manufactured gas plant (MGP) site. Concentrations of PAHs in MGP soils ranged from 335 to 8645 mg/kg. Of the potentially toxic metals, concentrations of lead were found to be highest, ranging from 88 to 671 mg/kg, cadmium 8 to 112 mg/kg, while zinc varied from 64 to 488 mg/kg. The enzyme activities were severely inhibited in soils that were contaminated with both PAHs and heavy metals. The presence of heavy metals in PAH-contaminated soils not only reduced the diversity of microbial population but also showed a few distinctive species by exerting selective pressure. The multivariate analysis revealed that there is an association between PAHs and heavy metals which influenced biological properties in mixed contaminated soils. The findings of this study have major implications for the bioremediation of organic pollutants in metal-organic mixed contaminated sites. Copyright © 2012 Elsevier Ltd. All rights reserved.
Association between employment status change and depression in Korean adults.
Yoo, Ki-Bong; Park, Eun-Cheol; Jang, Suk-Yong; Kwon, Jeoung A; Kim, Sun Jung; Cho, Kyoung-hee; Choi, Jae-Woo; Kim, Jae-Hyun; Park, Sohee
2016-03-01
This study investigated the association between employment status and depression. Data from the Korea Welfare Panel Study (KOWEPS) collected from 2008 to 2011 were used. A total of 7368 subjects were included in this study after exclusion of subjects with missing data and those who were self-employed or could not work. Depression was assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). Employment status, age, sex, region, education, marital status, income, head of household, self-rated health, smoking status, drinking habits, and the current year's and the previous year's CES-D scores were included in the model as independent variables. A generalised linear mixed-effects model for longitudinal binary data was used. Compared with those who were permanently employed, individuals who moved from permanent to precarious employment (OR 1.45, 95% CI 1.23 to 1.70) or to unemployment (OR 1.78, 95% CI 1.30 to 2.43) and from precarious employment to unemployment (OR 1.65, 95% CI 1.32 to 2.06) showed a significantly increased the odds of having depression. Continuing precarious employment (OR 1.54, 95% CI 1.30 to 1.83) or unemployment (OR 1.45, 95% CI 1.23 to 1.70) also significantly increased the odds of having depression. These results were particularly identified in men and head of household women. The effects were not significant among non-head of household women. Precarious employment and unemployment were clearly associated with having depression. In addition, in view of our findings, policy makers should consider sex and head of household status when developing welfare policies. The inequity between precarious jobs and permanent jobs should be tackled. 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/
NASA Technical Reports Server (NTRS)
Rind, David H.; Lerner, Jean; Shah, Kathy; Suozzo, Robert
1999-01-01
A key component of climate/chemistry modeling is how to handle the influx into (and egress from) the troposphere. This is especially important when considering tropospheric ozone, and its precursors (e.g., NO(x) from aircraft). A study has been conducted with various GISS models to determine the minimum requirements necessary for producing realistic troposphere-stratosphere exchange. Four on-line tracers are employed: CFC-11 and SF6 for mixing from the troposphere into the stratosphere, Rn222 for vertical mixing within the troposphere, and 14C for mixing from the stratosphere into the troposphere. Four standard models are tested, with varying vertical resolution, gravity wave drag and location of the model top, and additional subsidiary models are employed to examine specific features. The results show that proper vertical transport between the troposphere and stratosphere in the GISS models requires lifting the top of the model considerably out of the stratosphere, and including gravity wave drag in the lower stratosphere. Increased vertical resolution without these aspects does not improve troposphere-stratosphere exchange. The transport appears to be driven largely by the residual circulation within the stratosphere; associated E-P flux convergences require both realistic upward propagating energy from the troposphere, and realistic pass-through possibilities. A 23 layer version with a top at the mesopause and incorporating gravity wave drag appears to have reasonable stratospheric-tropospheric exchange, in terms of both the resulting tracer distributions and atmospheric mass fluxes.
Inverse Problems in Geodynamics Using Machine Learning Algorithms
NASA Astrophysics Data System (ADS)
Shahnas, M. H.; Yuen, D. A.; Pysklywec, R. N.
2018-01-01
During the past few decades numerical studies have been widely employed to explore the style of circulation and mixing in the mantle of Earth and other planets. However, in geodynamical studies there are many properties from mineral physics, geochemistry, and petrology in these numerical models. Machine learning, as a computational statistic-related technique and a subfield of artificial intelligence, has rapidly emerged recently in many fields of sciences and engineering. We focus here on the application of supervised machine learning (SML) algorithms in predictions of mantle flow processes. Specifically, we emphasize on estimating mantle properties by employing machine learning techniques in solving an inverse problem. Using snapshots of numerical convection models as training samples, we enable machine learning models to determine the magnitude of the spin transition-induced density anomalies that can cause flow stagnation at midmantle depths. Employing support vector machine algorithms, we show that SML techniques can successfully predict the magnitude of mantle density anomalies and can also be used in characterizing mantle flow patterns. The technique can be extended to more complex geodynamic problems in mantle dynamics by employing deep learning algorithms for putting constraints on properties such as viscosity, elastic parameters, and the nature of thermal and chemical anomalies.
Corrigan, Patrick W; Tsang, Hector W H; Shi, Kan; Lam, Chow S; Larson, Jon
2010-12-01
Work opportunities for people with behaviorally driven health conditions such as HIV/AIDS, drug abuse, alcohol abuse, and psychosis are directly impacted by employer perspectives. To investigate this issue, we report findings from a mixed method design involving qualitative interviews followed by a quantitative survey of employers from Chicago (U.S.), Beijing (China), and Hong Kong (China). Findings from qualitative interviews of 100 employers were used to create 27 items measuring employer perspectives (the Employer Perspective Scale: EPS) about hiring people with health conditions. These perspectives reflect reasons for or against discrimination. In the quantitative phase of the study, representative samples of approximately 300 employers per city were administered the EPS in addition to measures of stigma, including attributions about disease onset and offset. The EPS and stigma scales were completed in the context of one of five randomly assigned health conditions. We weighted data with ratios of key demographics between the sample and the corresponding employer population data. Analyses showed that both onset and offset responsibility varied by behaviorally driven condition. Analyses also showed that employer perspectives were more negative for health conditions that are seen as more behaviorally driven, e.g., drug and alcohol abuse. Chicago employers endorsed onset and offset attributions less strongly compared to those in Hong Kong and Beijing. Chicago employers also recognized more benefits of hiring people with various health conditions. The implications of these findings for better understanding stigma and stigma change among employers are considered. Copyright © 2010 Elsevier Ltd. All rights reserved.
Mustard, Cameron A; Skivington, Kathryn; Lay, Morgan; Lifshen, Marni; Etches, Jacob; Chambers, Andrea
2017-01-01
Objective This study describes the process and outcomes of the implementation of a strengthened disability management policy in a large Canadian healthcare employer. Key elements of the strengthened policy included an emphasis on early contact, the training of supervisors and the integration of union representatives in return-to-work (RTW) planning. Design The study applied mixed methods, combining a process evaluation within the employer and a quasi-experimental outcome evaluation between employers for a 3-year period prior to and following policy implementation in January 2012. Participants Staff in the implementation organisation (n=4000) and staff in a peer group of 29 large hospitals (n=1 19 000). Outcomes Work disability episode incidence and duration. Results Both qualitative and quantitative measures of the implementation process were predominantly positive. Over the 6-year observation period, there were 624 work disability episodes in the organisation and 8604 in the comparison group of 29 large hospitals. The annual per cent change in episode incidence in the organisation was −5.6 (95% CI −9.9 to −1.1) comparable to the annual per cent change in the comparison group: −6.2 (-7.2 to –5.3). Disability episode durations also declined in the organisation, from a mean of 19.4 days (16.5, 22.3) in the preintervention period to 10.9 days (8.7, 13.2) in the postintervention period. Reductions in disability durations were also observed in the comparison group: from a mean of 13.5 days (12.9, 14.1) in the 2009–2011 period to 10.5 days (9.9, 11.1) in the 2012–2014 period. Conclusion The incidence of work disability episodes and the durations of work disability declined strongly in this hospital sector over the 6-year observation period. The implementation of the organisation’s RTW policy was associated with larger reductions in disability durations than observed in the comparison group. PMID:28624757
The long road to employment: Incivility experienced by job seekers.
Ali, Abdifatah A; Ryan, Ann Marie; Lyons, Brent J; Ehrhart, Mark G; Wessel, Jennifer L
2016-03-01
This study addresses how job seekers' experiences of rude and discourteous treatment--incivility--can adversely affect self-regulatory processes underlying job searching. Using the social-cognitive model (Zimmerman, 2000), we integrate social-cognitive theory with the goal orientation literature to examine how job search self-efficacy mediates the relationship between incivility and job search behaviors and how individual differences in learning goal orientation and avoid-performance goal orientation moderate that process. We conducted 3 studies with diverse methods and samples. Study 1 employed a mixed-method design to understand the nature of incivility within the job search context and highlight the role of attributions in linking incivility to subsequent job search motivation and behavior. We tested our hypotheses in Study 2 and 3 employing time-lagged research designs with unemployed job seekers and new labor market entrants. Across both Study 2 and 3 we found evidence that the negative effect of incivility on job search self-efficacy and subsequent job search behaviors are stronger for individuals low, rather than high, in avoid-performance goal orientation. Theoretical implications of our findings and practical recommendations for how to address the influence of incivility on job seeking are discussed. (c) 2016 APA, all rights reserved).
Mixing and transient interface condensation of a liquid hydrogen tank
NASA Technical Reports Server (NTRS)
Lin, C. S.; Hasan, M. M.; Nyland, T. W.
1993-01-01
Experiments were conducted to investigate the effect of axial jet-induced mixing on the pressure reduction of a thermally stratified liquid hydrogen tank. The tank was nearly cylindrical, having a volume of about 0.144 cu m with 0.559 m in diameter and 0.711 m long. A mixer/pump unit, which had a jet nozzle outlet of 0.0221 m in diameter was located 0.178 m from the tank bottom and was installed inside the tank to generate the axial jet mixing and tank fluid circulation. The liquid fill and jet flow rate ranged from 42 to 85 percent (by volume) and 0.409 to 2.43 cu m/hr, respectively. Mixing tests began with the tank pressure ranging from 187.5 to 238.5 kPa at which the thermal stratification results in 4.9 to 6.2 K liquid sub cooling. The mixing time and transient vapor condensation rate at the liquid-vapor interface are determined. Two mixing time correlations, based on the thermal equilibrium and pressure equilibrium, are developed. Both mixing time correlations are expressed as functions of system and buoyancy parameters and compared well with other experimental data. The steady state condensation rate correlation of Sonin et al. based on steam-water data is modified and expressed as a function of jet subcooling. The limited liquid hydrogen data of the present study shows that the modified steady state condensation rate correlation may be used to predict the transient condensation rate in a mixing process if the instantaneous values of jet sub cooling and turbulence intensity at the interface are employed.
Conductivity detection for monitoring mixing reactions in microfluidic devices.
Liu, Y; Wipf, D O; Henry, C S
2001-08-01
A conductivity detector was coupled to poly(dimethylsiloxane)-glass capillary electrophoresis microchips to monitor microfluidic flow. Electroosmotic flow was investigated with both conductivity detection (CD) and the current monitoring method. No significant variation was observed between these methods, but CD showed a lower relative standard deviation. Gradient mixing experiments were employed to investigate the relationship between the electrolyte conductivity and the electrolyte concentration. A good linear response of conductivity to concentration was obtained for solutions whose difference in concentrations were less than 27 mM. The new system holds great promise for precision mixing in microfluidic devices using electrically driven flows.
Job design, employment practices and well-being: a systematic review of intervention studies.
Daniels, Kevin; Gedikli, Cigdem; Watson, David; Semkina, Antonina; Vaughn, Oluwafunmilayo
2017-09-01
There is inconsistent evidence that deliberate attempts to improve job design realise improvements in well-being. We investigated the role of other employment practices, either as instruments for job redesign or as instruments that augment job redesign. Our primary outcome was well-being. Where studies also assessed performance, we considered performance as an outcome. We reviewed 33 intervention studies. We found that well-being and performance may be improved by: training workers to improve their own jobs; training coupled with job redesign; and system wide approaches that simultaneously enhance job design and a range of other employment practices. We found insufficient evidence to make any firm conclusions concerning the effects of training managers in job redesign and that participatory approaches to improving job design have mixed effects. Successful implementation of interventions was associated with worker involvement and engagement with interventions, managerial commitment to interventions and integration of interventions with other organisational systems. Practitioner Summary: Improvements in well-being and performance may be associated with system-wide approaches that simultaneously enhance job design, introduce a range of other employment practices and focus on worker welfare. Training may have a role in initiating job redesign or augmenting the effects of job design on well-being.
A Broader Look at the U.S. Employment Situation and the Importance of a Good Education
ERIC Educational Resources Information Center
Greenstone, Michael; Looney, Adam
2011-01-01
The January employment numbers, released today by the U.S. Department of Labor, present mixed evidence about the state of the labor market. While the unemployment rate dropped to 9 percent, payrolls were just better than flat, increasing by only 36,000 jobs last month. Much attention is given to the official unemployment rate, which is certainly…
NASA Astrophysics Data System (ADS)
Song, Jung-Bin; Lee, Haigun
2012-12-01
A cooling system employing a solid cryogen (SC), such as solid nitrogen (SN2), was recently reported for high-temperature superconducting (HTS) applications. However, thermal contact between the SC and the HTS can be degraded by repeated overcurrent runs, resulting in 'thermal dry-out'. Novel cryogens, SC with small amounts of liquid cryogen, have been suggested to overcome this problem. Such cooling systems rely on the small amount of liquid cryogen to facilitate heat exchange so as to fully exploit the heat capacity of the solid cryogen. This paper presents a description and summary of recent activities at Korea University related to cooling systems employing mixed cryogens of solid-liquid nitrogen, solid argon-liquid nitrogen, and solid nitrogen-liquid neon.
Measurements of multi-scalar mixing in a turbulent coaxial jet
NASA Astrophysics Data System (ADS)
Hewes, Alais; Mydlarski, Laurent
2017-11-01
There are relatively few studies of turbulent multi-scalar mixing, despite the occurrence of this phenomenon in common processes (e.g. chemically reacting flows, oceanic mixing). In the present work, we simultaneously measure the evolution of two passive scalars (temperature and helium concentration) and velocity in a coaxial jet. Such a flow is particularly relevant, as coaxial jets are regularly employed in applications of turbulent non-premixed combustion, which relies on multi-scalar mixing. The coaxial jet used in the current experiment is based on the work of Cai et al. (J. Fluid Mech., 2011), and consists of a vertically oriented central jet of helium and air, surrounded by an annular flow of (unheated) pure air, emanating into a slow co-flow of (pure) heated air. The simultaneous two-scalar and velocity measurements are made using a 3-wire hot-wire anemometry probe. The first two wires of this probe form an interference (or Way-Libby) probe, and measure velocity and concentration. The third wire, a hot-wire operating at a low overheat ratio, measures temperature. The 3-wire probe is used to obtain concurrent velocity, concentration, and temperature statistics to characterize the mixing process by way of single and multivariable/joint statistics. Supported by the Natural Sciences and Engineering Research Council of Canada (Grant 217184).
Investigation of micromixing by acoustically oscillated sharp-edges
Nama, Nitesh; Huang, Po-Hsun; Huang, Tony Jun; Costanzo, Francesco
2016-01-01
Recently, acoustically oscillated sharp-edges have been utilized to achieve rapid and homogeneous mixing in microchannels. Here, we present a numerical model to investigate acoustic mixing inside a sharp-edge-based micromixer in the presence of a background flow. We extend our previously reported numerical model to include the mixing phenomena by using perturbation analysis and the Generalized Lagrangian Mean (GLM) theory in conjunction with the convection-diffusion equation. We divide the flow variables into zeroth-order, first-order, and second-order variables. This results in three sets of equations representing the background flow, acoustic response, and the time-averaged streaming flow, respectively. These equations are then solved successively to obtain the mean Lagrangian velocity which is combined with the convection-diffusion equation to predict the concentration profile. We validate our numerical model via a comparison of the numerical results with the experimentally obtained values of the mixing index for different flow rates. Further, we employ our model to study the effect of the applied input power and the background flow on the mixing performance of the sharp-edge-based micromixer. We also suggest potential design changes to the previously reported sharp-edge-based micromixer to improve its performance. Finally, we investigate the generation of a tunable concentration gradient by a linear arrangement of the sharp-edge structures inside the microchannel. PMID:27158292
NASA Astrophysics Data System (ADS)
Qyyum, Muhammad Abdul; Long, Nguyen Van Duc; Minh, Le Quang; Lee, Moonyong
2018-01-01
Design optimization of the single mixed refrigerant (SMR) natural gas liquefaction (LNG) process involves highly non-linear interactions between decision variables, constraints, and the objective function. These non-linear interactions lead to an irreversibility, which deteriorates the energy efficiency of the LNG process. In this study, a simple and highly efficient hybrid modified coordinate descent (HMCD) algorithm was proposed to cope with the optimization of the natural gas liquefaction process. The single mixed refrigerant process was modeled in Aspen Hysys® and then connected to a Microsoft Visual Studio environment. The proposed optimization algorithm provided an improved result compared to the other existing methodologies to find the optimal condition of the complex mixed refrigerant natural gas liquefaction process. By applying the proposed optimization algorithm, the SMR process can be designed with the 0.2555 kW specific compression power which is equivalent to 44.3% energy saving as compared to the base case. Furthermore, in terms of coefficient of performance (COP), it can be enhanced up to 34.7% as compared to the base case. The proposed optimization algorithm provides a deep understanding of the optimization of the liquefaction process in both technical and numerical perspectives. In addition, the HMCD algorithm can be employed to any mixed refrigerant based liquefaction process in the natural gas industry.
Investigation of micromixing by acoustically oscillated sharp-edges.
Nama, Nitesh; Huang, Po-Hsun; Huang, Tony Jun; Costanzo, Francesco
2016-03-01
Recently, acoustically oscillated sharp-edges have been utilized to achieve rapid and homogeneous mixing in microchannels. Here, we present a numerical model to investigate acoustic mixing inside a sharp-edge-based micromixer in the presence of a background flow. We extend our previously reported numerical model to include the mixing phenomena by using perturbation analysis and the Generalized Lagrangian Mean (GLM) theory in conjunction with the convection-diffusion equation. We divide the flow variables into zeroth-order, first-order, and second-order variables. This results in three sets of equations representing the background flow, acoustic response, and the time-averaged streaming flow, respectively. These equations are then solved successively to obtain the mean Lagrangian velocity which is combined with the convection-diffusion equation to predict the concentration profile. We validate our numerical model via a comparison of the numerical results with the experimentally obtained values of the mixing index for different flow rates. Further, we employ our model to study the effect of the applied input power and the background flow on the mixing performance of the sharp-edge-based micromixer. We also suggest potential design changes to the previously reported sharp-edge-based micromixer to improve its performance. Finally, we investigate the generation of a tunable concentration gradient by a linear arrangement of the sharp-edge structures inside the microchannel.
Spencer, Judy; Woodroffe, Jessica; Cross, Merylin; Allen, Penny
2015-01-01
Little is known about interprofessional practice (IPP) and interprofessional learning (IPL) in rural health services, despite national funding and continuing emphasis on increasing students' clinical placements in rural areas. This short paper outlines a study in Tasmania, Australia, which investigated how and under what contexts and conditions IPP and IPL occur in rural clinical settings, and the enabling factors and strategies that promote this learning and practice. This study employed a mixed method design comprising focus group discussions and a survey involving health professionals from two rural health services. The findings demonstrate that formal and informal arrangements, the collaborative nature of small, close-knit healthcare teams and patient-centred models of care employed in rural practice settings, provide ideal contexts for IPP and IPL. The study has implications for promoting organisational readiness for IPP and IPL and harnessing the potential of rural services to promote and develop students' interprofessional capability.
Jackson, Bret; Coffey, Dane; Thorson, Lauren; Schroeder, David; Ellingson, Arin M; Nuckley, David J; Keefe, Daniel F
2012-10-01
In this position paper we discuss successes and limitations of current evaluation strategies for scientific visualizations and argue for embracing a mixed methods strategy of evaluation. The most novel contribution of the approach that we advocate is a new emphasis on employing design processes as practiced in related fields (e.g., graphic design, illustration, architecture) as a formalized mode of evaluation for data visualizations. To motivate this position we describe a series of recent evaluations of scientific visualization interfaces and computer graphics strategies conducted within our research group. Complementing these more traditional evaluations our visualization research group also regularly employs sketching, critique, and other design methods that have been formalized over years of practice in design fields. Our experience has convinced us that these activities are invaluable, often providing much more detailed evaluative feedback about our visualization systems than that obtained via more traditional user studies and the like. We believe that if design-based evaluation methodologies (e.g., ideation, sketching, critique) can be taught and embraced within the visualization community then these may become one of the most effective future strategies for both formative and summative evaluations.
Jackson, Bret; Coffey, Dane; Thorson, Lauren; Schroeder, David; Ellingson, Arin M.; Nuckley, David J.
2017-01-01
In this position paper we discuss successes and limitations of current evaluation strategies for scientific visualizations and argue for embracing a mixed methods strategy of evaluation. The most novel contribution of the approach that we advocate is a new emphasis on employing design processes as practiced in related fields (e.g., graphic design, illustration, architecture) as a formalized mode of evaluation for data visualizations. To motivate this position we describe a series of recent evaluations of scientific visualization interfaces and computer graphics strategies conducted within our research group. Complementing these more traditional evaluations our visualization research group also regularly employs sketching, critique, and other design methods that have been formalized over years of practice in design fields. Our experience has convinced us that these activities are invaluable, often providing much more detailed evaluative feedback about our visualization systems than that obtained via more traditional user studies and the like. We believe that if design-based evaluation methodologies (e.g., ideation, sketching, critique) can be taught and embraced within the visualization community then these may become one of the most effective future strategies for both formative and summative evaluations. PMID:28944349
NASA Astrophysics Data System (ADS)
Lee, Serena B.; Birch, Gavin F.
2012-10-01
Estuarine health is affected by contamination from stormwater, particularly in highly-urbanised environments. For systems where catchment monitoring is insufficient, novel techniques must be employed to determine the impact of urban runoff on receiving water bodies. In the present work, estuarine monitoring and modelling were successfully employed to determine stormwater runoff volumes and establish an appropriate rainfall/runoff relationship capable of replicating fresh-water discharge due to the full range of precipitation conditions in the Sydney Estuary, Australia. Using estuary response to determine relationships between catchment rainfall and runoff is a widely applicable method and may be of assistance in the study of waterways where monitoring fluvial discharges is not practical or is beyond the capacity of management authorities. For the Sydney Estuary, the SCS-CN method replicated rainfall/runoff and was applied in numerical modelling experiments investigating the hydrodynamic characteristics affecting stratification and estuary recovery following high precipitation. Numerical modelling showed stratification in the Sydney Estuary was dominated by fresh-water discharge. Spring tides and up-estuary winds contributed to mixing and neap tides and down-estuary winds enhanced stratification.
Klussmann, Andre; Liebers, Falk; Brandstädt, Felix; Schust, Marianne; Serafin, Patrick; Schäfer, Andreas; Gebhardt, Hansjürgen; Hartmann, Bernd; Steinberg, Ulf
2017-08-21
The impact of work-related musculoskeletal disorders is considerable. The assessment of work tasks with physical workloads is crucial to estimate the work-related health risks of exposed employees. Three key indicator methods are available for risk assessment regarding manual lifting, holding and carrying of loads; manual pulling and pushing of loads; and manual handling operations. Three further KIMs for risk assessment regarding whole-body forces, awkward body postures and body movement have been developed de novo. In addition, the development of a newly drafted combined method for mixed exposures is planned. All methods will be validated regarding face validity, reliability, convergent validity, criterion validity and further aspects of utility under practical conditions. As part of the joint project MEGAPHYS (multilevel risk assessment of physical workloads), a mixed-methods study is being designed for the validation of KIMs and conducted in companies of different sizes and branches in Germany. Workplaces are documented and analysed by observations, applying KIMs, interviews and assessment of environmental conditions. Furthermore, a survey among the employees at the respective workplaces takes place with standardised questionnaires, interviews and physical examinations. It is intended to include 1200 employees at 120 different workplaces. For analysis of the quality criteria, recommendations of the COSMIN checklist (COnsensus-based Standards for the selection of health Measurement INstruments) will be taken into account. The study was planned and conducted in accordance with the German Medical Professional Code and the Declaration of Helsinki as well as the German Federal Data Protection Act. The design of the study was approved by ethics committees. We intend to publish the validated KIMs in 2018. Results will be published in peer-reviewed journals, presented at international meetings and disseminated to actual users for practical application. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Verzhbitskiy, I A; Kouzov, A P; Rachet, F; Chrysos, M
2011-06-14
A line-mixing shape analysis of the isotropic remnant Raman spectrum of the 2ν(3) overtone of CO(2) is reported at room temperature and for densities, ρ, rising up to tens of amagats. The analysis, experimental and theoretical, employs tools of non-resonant light scattering spectroscopy and uses the extended strong collision model (ESCM) to simulate the strong line mixing effects and to evidence motional narrowing. Excellent agreement at any pressure is observed between the calculated spectra and our experiment, which, along with the easy numerical implementation of the ESCM, makes this model stand out clearly above other semiempirical models for band shape calculations. The hitherto undefined, explicit ρ-dependence of the vibrational relaxation rate is given. Our study intends to improve the understanding of pressure-induced phenomena in a gas that is still in the forefront of the news.
Primal-mixed formulations for reaction-diffusion systems on deforming domains
NASA Astrophysics Data System (ADS)
Ruiz-Baier, Ricardo
2015-10-01
We propose a finite element formulation for a coupled elasticity-reaction-diffusion system written in a fully Lagrangian form and governing the spatio-temporal interaction of species inside an elastic, or hyper-elastic body. A primal weak formulation is the baseline model for the reaction-diffusion system written in the deformed domain, and a finite element method with piecewise linear approximations is employed for its spatial discretization. On the other hand, the strain is introduced as mixed variable in the equations of elastodynamics, which in turn acts as coupling field needed to update the diffusion tensor of the modified reaction-diffusion system written in a deformed domain. The discrete mechanical problem yields a mixed finite element scheme based on row-wise Raviart-Thomas elements for stresses, Brezzi-Douglas-Marini elements for displacements, and piecewise constant pressure approximations. The application of the present framework in the study of several coupled biological systems on deforming geometries in two and three spatial dimensions is discussed, and some illustrative examples are provided and extensively analyzed.
Widjanarko, Simon Bambang; Amalia, Qory; Hermanto, Mochamad Bagus; Mubarok, Ahmad Zaki
2018-05-01
In the present study, the effect of two independent variables, yellow konjac flour-κ-carrageenan (KFC) mixed gels and red koji rice (RKR) extracts for the development of restructured meat product, was investigated using central composite design of response surface methodology (RSM). The assessed physical characteristics were hardness, water holding capacity (WHC), and color (° hue ) of the restructured meat products. The second order regression models with high R 2 value were significantly fitted to predict the changes in hardness, WHC and color. The results showed that the predicted optimum formula of restructured meat were the addition of KFC mixed gels at 10.21% and RKR extracts at 6.11%. The experiments results validate these optimum formula and found to be not statistically different at 5% level. Thus, the RSM was successfully employed and can be used to optimize the formulation of restructured meat.
NASA Astrophysics Data System (ADS)
Li, Jie; Zhang, Yu; Ma, Kai; Pan, Xi-De; Li, Cheng-Xin; Yang, Guan-Jun; Li, Chang-Jiu
2018-02-01
In this study, vacuum cold spraying was used as a simple and fast way to prepare transparent super-hydrophobic coatings. Submicrometer-sized Al2O3 powder modified by 1,1,2,2-tetrahydroperfluorodecyltriethoxysilane and mixed with hydrophobic SiO2 aerogel was employed for the coating deposition. The deposition mechanisms of pure Al2O3 powder and Al2O3-SiO2 mixed powder were examined, and the effects of powder structure on the hydrophobicity and light transmittance of the coatings were evaluated. The results showed that appropriate contents of SiO2 aerogel in the mixed powder could provide sufficient cushioning to the deposition of submicrometer Al2O3 powder during spraying. The prepared composite coating surface showed rough structures with a large number of submicrometer convex deposited particles, characterized by being super-hydrophobic. Also, the transmittance of the obtained coating was higher than 80% in the range of visible light.
Bardhan, Soumik; Kundu, Kaushik; Das, Sajal; Poddar, Madhumita; Saha, Swapan K; Paul, Bidyut K
2014-09-15
Modification of the interface by blending of surfactants produces considerable changes in the elastic rigidity of the interface, which in turn affects the physicochemical properties of w/o microemulsions. Hence, it could be possible to tune the thermodynamic properties, microstructures and antimicrobial activity of microemulsions by using ionic/non-ionic mixed surfactants and polar lipophilic oil, which are widely used in biologically relevant systems. The present report was aimed at precise characterization of mixed cetyltrimethylammonium bromide and polyoxyethylene (23) lauryl ether microemulsions stabilized in 1-pentanol (Pn) and isopropyl myristate at different physicochemical conditions by employing phase studies, the dilution method, conductivity, DLS, FTIR (with HOD probing) and (1)H NMR measurements. Further, microbiological activities at different compositions were examined against two bacterial strains Bacillus subtilis and Escherichia coli at 303 K. The formation of mixed surfactant microemulsions was found to be spontaneous at all compositions, whereas it was endothermic at equimolar composition. FTIR and (1)H NMR measurements showed the existence of bulk-like, bound and trapped water molecules in confined environments. Interestingly, composition dependence of both highest and lowest inhibitory effects was observed against the bacterial strains, whereas similar features in spontaneity of microemulsion formation were also evidenced. These results suggested a close relationship between thermodynamic stability and antimicrobial activities. Such studies on polar lipophilic oil derived mixed surfactant microemulsions have not been reported earlier. Copyright © 2014 Elsevier Inc. All rights reserved.
Effects of two warm-mix additives on aging, rheological and failure properties of asphalt cements
NASA Astrophysics Data System (ADS)
Omari, Isaac Obeng
Sustainable road construction and maintenance could be supported when excellent warm-mix additives are employed in the modification of asphalt. These warm-mix additives provide remedies for today's requirements such as fatigue cracking resistance, durability, thermal cracking resistance, rutting resistance and resistance to moisture damage. Warm-mix additives are based on waxes and surfactants which reduce energy consumption and carbon dioxide emissions significantly during the construction phase of the pavement. In this study, the effects of two warm mix additives, siloxane and oxidised polyethylene wax, on roofing asphalt flux (RAF) and asphalt modified with waste engine oil (655-7) were investigated to evaluate the rheological, aging and failure properties of the asphalt binders. In terms of the properties of these two different asphalts, RAF has proved to be superior quality asphalt whereas 655-7 is poor quality asphalt. The properties of the modified asphalt samples were measured by Superpave(TM) tests such as Dynamic Shear Rheometer (DSR) test and Bending Beam Rheometer (BBR) test as well as modified protocols such as the extended BBR (eBBR) test (LS-308) and the Double- Edge-Notched Tension (DENT) test (LS-299) after laboratory aging. In addition, the Avrami theory was used to gain an insight on the crystallization of asphalt or the waxes within the asphalt binder. This study has however shown that the eBBR and DENT tests are better tools for providing accurate specification tests to curb thermal and fatigue cracking in contemporary asphalt pavements.
Mass and momentum turbulent transport experiments with confined swirling coaxial jets
NASA Technical Reports Server (NTRS)
Roback, R.; Johnson, B. V.
1983-01-01
Swirling coaxial jets mixing downstream, discharging into an expanded duct was conducted to obtain data for the evaluation and improvement of turbulent transport models currently used in a variety of computational procedures throughout the combustion community. A combination of laser velocimeter (LV) and laser induced fluorescence (LIF) techniques was employed to obtain mean and fluctuating velocity and concentration distributions which were used to derive mass and momentum turbulent transport parameters currently incorporated into various combustor flow models. Flow visualization techniques were also employed to determine qualitatively the time dependent characteristics of the flow and the scale of turbulence. The results of these measurements indicated that the largest momentum turbulent transport was in the r-z plane. Peak momentum turbulent transport rates were approximately the same as those for the nonswirling flow condition. The mass turbulent transport process for swirling flow was complicated. Mixing occurred in several steps of axial and radial mass transport and was coupled with a large radial mean convective flux. Mixing for swirling flow was completed in one-third the length required for nonswirling flow.
Effects of a multifaceted minimal-lift environment for nursing staff: pilot results.
Zadvinskis, Inga M; Salsbury, Susan L
2010-02-01
Nursing staff are at risk for musculoskeletal injuries because of the physical nature of patient handling. The purpose of this study is to examine the effectiveness of a multifaceted minimal-lift environment on reported equipment use, musculoskeletal injury rates, and workers' compensation costs for patient-handling injuries. The pilot study consists of a mixed measures design, with both descriptive and quasi-experimental design elements. The intervention consists of engineering (minimal-lift equipment), administrative (nursing policy), and behavioral (peer coach program) controls. The comparison nursing unit has received engineering controls only. The convenience sample includes nursing staff employed on two medical-surgical nursing units, who provide direct patient care at least 50% of the time. Nursing staff employed in a multifaceted lift environment report greater lift equipment use and experience less injury, with reduced worker's compensation costs.
Mixing due Pulsating Turbulent Jets
NASA Astrophysics Data System (ADS)
Grosshans, Holger; Nygård, Alexander; Fuchs, Laszlo
Combustion efficiency and the formation of soot and/or NOx in Internal- Combustion engines depends strongly on the local air/fuel mixture, the local flow conditions and temperature. Modern diesel engines employ high injection pressure for improved atomization, but mixing is controlled largely by the flow in the cylinder. By injecting the fuel in pulses one can gain control over the atomization, evaporation and the mixing of the gaseous fuel. We show that the pulsatile injection of fuel enhances fuel break-up and the entrainment of ambient air into the fuel stream. The entrainment level depends on fuel property, such as fuel/air viscosity and density ratio, fuel surface-tension, injection speed and injection sequencing. Examples of enhanced break-up and mixing are given.
Numerical Investigations of Wave-Induced Mixing in Upper Ocean Layer
NASA Astrophysics Data System (ADS)
Guan, Changlong
2017-04-01
The upper ocean layer is playing an important role in ocean-atmosphere interaction. The typical characteristics depicting the upper ocean layer are the sea surface temperature (SST) and the mixed layer depth (MLD). So far, the existing ocean models tend to over-estimate SST and to under-estimate MLD, due to the inadequate mixing in the mixing layer, which is owing to that several processes related mixing in physics are ignored in these ocean models. The mixing induced by surface gravity wave is expected to be able to enhance the mixing in the upper ocean layer, and therefore the over-estimation of SST and the under-estimate of MLD could be improved by including wave-induced mixing. The wave-induced mixing could be accomplished by the physical mechanisms, such as wave breaking (WB), wave-induced Reynolds stress (WR), and wave-turbulence interaction (WT). The General Ocean Turbulence Model (GOTM) is employed to investigate the effects of the three mechanisms concerning wave-induced mixing. The numerical investigation is carried out for three turbulence closure schemes, say, k-epsilon, k-omega and Mellor-Yamada (1982), with the observational data from OSC Papa station and wave data from ECMWF. The mixing enhancement by various waved-induced mixing mechanisms is investigated and verified.
CFD analysis of jet mixing in low NOx flametube combustors
NASA Technical Reports Server (NTRS)
Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.
1991-01-01
The Rich-burn/Quick-mix/Lean-burn (RQL) combustor was identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3-D CFD analyses for optimizing jet mixing was demonstrated.
CFD analysis of jet mixing in low NO(x) flametube combustors
NASA Technical Reports Server (NTRS)
Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.
1991-01-01
The Rich-burn/Quick-mix/Lean-burn (RQL) combustor has been identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3D CFD analyses for optimizing jet mixing was demonstrated.
Theis, K A; Roblin, D; Helmick, C G; Luo, R
2018-05-28
Negative employment consequences of arthritis are known but not fully understood. Examining transitions in and out of work can provide valuable information. To examine associations of arthritis with employment during the Great Recession and predictors of employment transitions. Data were for 3,277 adults ages 30-62 years with and without arthritis from the 2007 National Health Interview Survey followed in the Medical Expenditure Panel Survey 2008-2009. Employment (working vs. not working) was ascertained at baseline and five follow-ups. We estimated Kaplan Meier survival curves with 95% confidence intervals (CI) separately for time to stopping work (working at baseline) and starting work (not working at baseline) using Cox proportional hazards regression models with hazard ratios (HR). Arthritis was significantly associated with greater risk of stopping work (HR = 1.7, 95% CI = 1.3-2.2; adjusted HR= 1.5, 95% CI = 1.1-2.0) and significantly associated with 40% lower chance of starting work (HR = 0.6, 95% CI = 0.4-0.8); which reversed on adjustment (HR = 1.5, 95% CI = 1.0-2.2). Employment predictors were mixed by outcome. During the Great Recession, adults with arthritis stopped work at higher rates and started work at lower rates than those without arthritis.
Hu, Xiao; Zeng, Mengqi; Long, Yun; Liu, Jun; Zhu, Yixiao; Zou, Kaiheng; Zhang, Fan; Fu, Lei; Wang, Jian
2016-01-01
We fabricate a nonlinear optical device based on a fiber pigtail cross-section coated with a single-layer graphene grown by chemical vapor deposition (CVD) method. Using the fabricated graphene-assisted nonlinear optical device and employing Nyquist 16-ary quadrature amplitude modulation (16-QAM) signal, we experimentally demonstrate phase conjugated wavelength conversion by degenerate four-wave mixing (FWM) and transparent wavelength conversion by non-degenerate FWM in graphene. We study the conversion efficiency as functions of the pump power and pump wavelength and evaluate the bit-error rate (BER) performance. We also compare the time-varying symbol sequence for graphene-assisted phase conjugated and transparent wavelength conversions of Nyquist 16-QAM signal. PMID:26932470
Damage monitoring in historical murals by speckle interferometry
NASA Astrophysics Data System (ADS)
Hinsch, Klaus D.; Gulker, Gerd; Joost, Holger
2003-11-01
In the conservation of historical murals it is important to identify loose plaster sections that threaten to fall off. Electronic speckle interferometry in combination with acoustic excitation of the object has been employed to monitor loose areas. To avoid disadvantages of high sound irradiation of the complete building a novel directional audio-sound source based on nonlinear mixing of ultrasound has been introduced. The optical system was revised for optimum performance in the new environment. Emphasis is placed on noise suppression to increase sensitivity. Furthermore, amplitude and phase data of object response over the frequency-range inspected are employed to gain additional information on the state of the plaster or paint. Laboratory studies on sample specimen supplement field campaigns at historical sites.
An analysis of turbulent diffusion flame in axisymmetric jet
NASA Technical Reports Server (NTRS)
Chung, P. M.; Im, K. H.
1980-01-01
The kinetic theory of turbulent flow was employed to study the mixing limited combustion of hydrogen in axisymmetric jets. The integro-differential equations in two spatial and three velocity coordinates describing the combustion were reduced to a set of hyperbolic partial differential equations in the two spatial coordinates by a binodal approximation. The MacCormick's finite difference method was then employed for solution. The flame length was longer than that predicted by the flame-sheet analysis, and was found to be in general agreement with a recent experimental result. Increase of the turbulence energy and scale resulted in an enhancement of the combustion rate and, hence, in a shorter flame length. Details of the numerical method as well as of the physical findings are discussed.
Rosenheck, Robert; Mueser, Kim T; Sint, Kyaw; Lin, Haiqun; Lynde, David W; Glynn, Shirley M; Robinson, Delbert G; Schooler, Nina R; Marcy, Patricia; Mohamed, Somaia; Kane, John M
2017-04-01
Participation in work and school are central objectives for first episode psychosis (FEP) programs, but evidence effectiveness has been mixed in studies not focused exclusively on supported employment and education (SEE). Requirements for current motivation to work or go to school limit the generalizability of such studies. FEP participants (N=404) at thirty-four community treatment clinics participated in a cluster randomized trial that compared usual Community Care (CC) to NAVIGATE, a comprehensive, team-based treatment program that included ≥5h of SEE services per week, , grounded in many of the principles of the Individual Placement and Support model of supported employment combined with supported education services. All study participants were offered SEE regardless of their initial interest in work or school. Monthly assessments over 24months recorded days of employment and attendance at school, days of participation in SEE, and both employment and public support income (including disability income). General Estimation Equation models were used to compare CC and NAVIGATE on work and school participation, employment and public support income, and the mediating effect of receiving ≥3 SEE visits on these outcomes. NAVIGATE treatment was associated with a greater increase in participation in work or school (p=0.0486) and this difference appeared to be mediated by SEE. No group differences were observed in earnings or public support payments. A comprehensive, team-based FEP treatment approach was associated with greater improvement in work or school participation, and this effect appears to be mediated, in part, by participation in SEE. Published by Elsevier B.V.
Hasson-Ohayon, Ilanit; Roe, David; Yanos, Philip T; Lysaker, Paul H
2016-12-01
Recent developments in mental health have emphasized recovery as an outcome for people with serious mental illness (SMI). Accordingly, several studies have attempted to evaluate the process and outcome of recovery-oriented psychosocial interventions. To review and discuss quantitative and qualitative findings from previous efforts to study the impact of five recovery-oriented interventions: Illness Management and Recovery (IMR), Narrative Enhancement and Cognitive Therapy (NECT), Supported Employment (SE), Supported Socialization (SS), and Family Psychoeducation. Reviewing the literature on studies that examine the effectiveness of these interventions by using both quantitative and qualitative approach. Qualitative findings in these studies augment quantitative findings and at times draw attention to unexpected findings and uniquely illuminate the effects of these interventions on self-reflective processes. There is a need for further exploration of how mixed-methods can be implemented to explore recovery-oriented outcomes. Critical questions regarding the implications of qualitative findings are posed.
Nicholson, Joanne; Wright, Spenser M; Carlisle, Alyssa M
2018-02-06
Successful competitive employment has been found to be related to enhanced self-esteem, higher quality of life and reduced mental health service use for individuals living with serious mental illnesses (SMIs) including schizophrenia, bipolar disorder and major depression. The effectiveness of the individual placement and support model has been demonstrated in multiple randomised controlled trials in many countries. The management of stress, depression and anxiety in the workplace may be effectively enhanced through digital mental health interventions. The WorkingWell mobile support tool ('app') is specifically designed to meet the need for illness management support for individuals with SMI in the workplace, as an adjunct to professional treatment. The WorkingWell app, grounded in evidence-based supported employment, is informed by user experience design. It will be tested in a pre-post design, mixed-methods pilot study to explore issues of feasibility, acceptability and usefulness, and to provide preliminary data on the impact of use. Putative mediators of improved job tenure and psychological well-being, including postintervention changes in social support, self-efficacy and work-related motivation, will be investigated. Forty individuals at least 18 years of age, meeting the eligibility requirements for supported employment services (ie, diagnosed with a mental illness meeting the criteria for severity, duration and treatment), working a minimum of 10 hours per week at study enrolment, and speaking, reading and writing in English will be recruited for the pilot study. Research staff will recruit individuals at community-based mental health agencies; provide orientation to the study, the study smartphones and the WorkingWell app; conduct research interviews including standardised measures as well as semistructured items; and provide technical assistance in telephone calls and inperson meetings. A sample of 10 agency staff will be recruited to obtain further information on the feasibility, acceptability and usefulness of WorkingWell. The study design and procedures are approved by the Dartmouth-Hitchcock Medical Center Committee for the Protection of Human Subjects, the Massachusetts Department of Mental Health Central Office Research Review Committee and the Vermont Agency of Human Services Institutional Review Board. Study findings will be disseminated to agency partners, state agencies and funders, and to the research and technology development communities. Findings from the study will inform the design, data collection procedures and protocol for future full-scale randomised controlled trial testing of the effectiveness of the WorkingWell app, as well as investigations of work-related variables as mediators of psychological well-being and quality of life for individuals with SMI. © 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 global renewable mix with proven technologies and common materials
NASA Astrophysics Data System (ADS)
Ballabrera, J.; Garcia-Olivares, A.; Garcia-Ladona, E.; Turiel, A.
2012-04-01
A global alternative mix to fossil fuels is proposed, based on proven renewable energy technologies that do not use scarce materials. Taking into account the availability of materials, the resulting mix consists of a combination of onshore and offshore wind turbines, concentrating solar power stations, hydroelectricity and wave power devices attached to the offshore turbines. Solar photovoltaic power could contribute to the mix if its dependence on scarce materials is solved. Material requirements are studied for the generation, power transport and for some future transport systems. The order of magnitude of copper, aluminium, neodymium, lithium, nickel, zinc and platinum that might be required for the proposed solution is obtained and compared with available reserves. While the proposed global alternative to fossil fuels seems technically feasible, lithium, nickel and platinum could become limiting materials for future vehicles fleet if no global recycling system were implemented and rechargeable zinc-air batteries could not be developed. As much as 60% of the current copper reserves would have to be employed in the implementation of the proposed solution. Altogether, the availability of materials may become a long-term physical constraint, preventing the continuation of the usual exponential growth of energy consumption.
NASA Technical Reports Server (NTRS)
Graf, Wiley E.
1991-01-01
A mixed formulation is chosen to overcome deficiencies of the standard displacement-based shell model. Element development is traced from the incremental variational principle on through to the final set of equilibrium equations. Particular attention is paid to developing specific guidelines for selecting the optimal set of strain parameters. A discussion of constraint index concepts and their predictive capability related to locking is included. Performance characteristics of the elements are assessed in a wide variety of linear and nonlinear plate/shell problems. Despite limiting the study to geometric nonlinear analysis, a substantial amount of additional insight concerning the finite element modeling of thin plate/shell structures is provided. For example, in nonlinear analysis, given the same mesh and load step size, mixed elements converge in fewer iterations than equivalent displacement-based models. It is also demonstrated that, in mixed formulations, lower order elements are preferred. Additionally, meshes used to obtain accurate linear solutions do not necessarily converge to the correct nonlinear solution. Finally, a new form of locking was identified associated with employing elements designed for biaxial bending in uniaxial bending applications.
The evaporatively driven cloud-top mixing layer
NASA Astrophysics Data System (ADS)
Mellado, Juan Pedro
2010-11-01
Turbulent mixing caused by the local evaporative cooling at the top cloud-boundary of stratocumuli will be discussed. This research is motivated by the lack of a complete understanding of several phenomena in that important region, which translates into an unacceptable variability of order one in current models, including those employed in climate research. The cloud-top mixing layer is a simplified surrogate to investigate, locally, particular aspects of the fluid dynamics at the boundary between the stratocumulus clouds and the upper cloud-free air. In this work, direct numerical simulations have been used to study latent heat effects. The problem is the following: When the cloud mixes with the upper cloud-free layer, relatively warm and dry, evaporation tends to cool the mixture and, if strong enough, the buoyancy reversal instability develops. This instability leads to a turbulent convection layer growing next to the upper boundary of the cloud, which is, in several aspects, similar to free convection below a cold horizontal surface. In particular, results show an approximately self-preserving behavior that is characterized by the molecular buoyancy flux at the inversion base, fact that helps to explain the difficulties found when doing large-eddy simulations of this problem using classical subgrid closures.