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1 – 10 of over 6000Paweł Ziółkowski and Janusz Badur
The purpose of this paper is the theoretical presentation of tensorial formulation with surface mobility forces and numerical verification of Reynolds thermal transpiration law in…
Abstract
Purpose
The purpose of this paper is the theoretical presentation of tensorial formulation with surface mobility forces and numerical verification of Reynolds thermal transpiration law in a contemporary experiment with nanoflow.
Design/methodology/approach
The velocity profiles in a single microchannel are calculated by solving the momentum equations and using thermal transpiration force as the boundary conditions. The mass flow rate and pressure of unstationary thermal transpiration modeling of the benchmark experiment has been achieved by the implementation of the thermal transpiration mobility force closure for the thermal momentum accommodation coefficient.
Findings
An original and easy-to-implement method has been developed to numerically prove that at the final equilibrium, i.e. zero-flow state, there is a connection between the Poiseuille flow in the center of channel and counter thermal transpiration flow on the surface. The numerical implementation of the Reynolds model of thermal transpiration has been performed, and its usefulness for the description of the benchmark experiment has been verified.
Research limitations/implications
The simplified procedure requires the measurement or assumption of the helium-glass slip length.
Practical implications
The procedure can be very useful in the design of micro-electro-mechanical systems and nano-electro-mechanical systems, especially for accommodation pumping.
Originality/value
The paper discussed possible constitutive equations in the transpiration shell-like layer. The new approach can be helpful for modeling phenomena occurring at a fluid–solid phase interface at the micro- and nanoscales.
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Nancy J. Mezey, Lori A. Post and Christopher D. Maxwell
This study examines the relationship between age, physical violence and non‐physical abuse within the context of intimate partner violence (IPV). It tests the hypothesis that…
Abstract
This study examines the relationship between age, physical violence and non‐physical abuse within the context of intimate partner violence (IPV). It tests the hypothesis that while the prevalence of physical violence is lower among older women, other forms of intimate partner violence are not related to age. The study uses data from the Michigan Violence Against Women Survey to measure physical violence and two forms of non‐physical abuse: psychological vulnerability and autonomy‐limiting behavior. Findings support the hypothesis that the rate of physical abuse is negatively related to age but the rate of nonphysical abuse is not. By expanding the definition of IPV to include other forms of abusive behavior, the study finds that older women have IPV prevalence rates similar to younger women. This raises the question of whether batterers alter their means of power and control by emphasizing non‐physical abuse rather than continuing to use physical violence that exposes them to formal and informal social controls and sanctions.
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C.A. Maxwell‐Armstrong, M. Jonas, S. Hussein, J. Wright and J.H. Scholefield
Twenty‐four hour pH monitoring is an expensive, time‐consuming and uncomfortable investigation only necessary in a small proportion of patients with gastro‐oesophageal reflux…
Abstract
Twenty‐four hour pH monitoring is an expensive, time‐consuming and uncomfortable investigation only necessary in a small proportion of patients with gastro‐oesophageal reflux disease. Guidelines have been published by the British Society of Gastroenterology, in order to clarify those patients likely to benefit. Aims to assess whether these guidelines are being followed in a large teaching hospital. A random selection of the notes of all patients referred for 24‐hour pH monitoring at the Queens Medical Centre were assessed for the appropriateness of referral. A total of 114 patients were referred for pH monitoring, and the notes of 77 of them reviewed. This audit shows that in the majority of cases guidelines are being followed. Referrals from non‐gastrointestinal specialties accounted for 50 per cent of cases where they were not. In addition, 40 per cent of all referrals from non‐gastrointestinal specialties failed to follow guidelines, suggesting that this group is either educated further as to their contents, or that all patients referred for 24‐hour pH monitoring see a medical or surgical gastroenterologist prior to the investigation.
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Michael A. Hansen and John C. Navarro
The purpose of this study is to explore the ideological gaps across a range of policing interactions with the public.
Abstract
Purpose
The purpose of this study is to explore the ideological gaps across a range of policing interactions with the public.
Design/methodology/approach
In a survey distributed via Mechanical Turk (MTurk) (n = 979), the authors explore the role that respondents' political ideology plays in the agreement of 13 aspects of policing services, their demeanor and decorum.
Findings
Attitudes toward policing interactions are slightly positive. Conservatives steadfastly hold positive attitudes about police. Liberals vacillate from negative to positive attitudes across the 13 policing interaction statements.
Social implications
Although small, there is an ideological consensus that police adequately protect citizens and are knowledgeable about the law.
Originality/value
Even at record lows of public confidence in the police, some subsections of the sample, such as conservatives, firmly hold positive attitudes about police. The unwavering support for police by conservatives continues across the multi-item measure of policing interactions, whereas liberals illustrated less uniformity in their attitudes.
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The decline in cigarette consumption within developed countriesmakes the exploitation of new markets particularly important to tobaccocompanies. UK data on exports is used to show…
Abstract
The decline in cigarette consumption within developed countries makes the exploitation of new markets particularly important to tobacco companies. UK data on exports is used to show that, by splitting the sample into three groups, income and prices have significant but different effects on cigarette import demand according to country type. Additionally the extent to which firms vary prices according to these internal circumstances in an effort to increase total consumption is examined. Stresses that, while exports to newly industrializing and oil exporting countries have risen most dramatically, markets in Less Developed Countries are also a fertile source of future sales and may provide a focus for future policy co‐ordination.
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Md Motiur Rahaman, Nirmalendu Biswas, Apurba Kumar Santra and Nirmal K. Manna
This study aims to delve into the coupled mixed convective heat transport process within a grooved channel cavity using CuO-water nanofluid and an inclined magnetic field. The…
Abstract
Purpose
This study aims to delve into the coupled mixed convective heat transport process within a grooved channel cavity using CuO-water nanofluid and an inclined magnetic field. The cavity undergoes isothermal heating from the bottom, with variations in the positions of heated walls across the grooved channel. The aim is to assess the impact of heater positions on thermal performance and identify the most effective configuration.
Design/methodology/approach
Numerical solutions to the evolved transport equations are obtained using a finite volume method-based indigenous solver. The dimensionless parameters of Reynolds number (1 ≤ Re ≤ 500), Richardson number (0.1 ≤ Ri ≤ 100), Hartmann number (0 ≤ Ha ≤ 70) and magnetic field inclination angle (0° ≤ γ ≤ 180°) are considered. The solved variables generate both local and global variables after discretization using the semi-implicit method for pressure linked equations algorithm on nonuniform grids.
Findings
The study reveals that optimal heat transfer occurs when the heater is positioned at the right corner of the grooved cavity. Heat transfer augmentation ranges from 0.5% to 168.53% for Re = 50 to 300 compared to the bottom-heated case. The magnetic field’s orientation significantly influences the average heat transfer, initially rising and then declining with increasing inclination angle. Overall, this analysis underscores the effectiveness of heater positions in achieving superior thermal performance in a grooved channel cavity.
Research limitations/implications
This concept can be extended to explore enhanced thermal performance under various thermal boundary conditions, considering wall curvature effects, different geometry orientations and the presence of porous structures, either numerically or experimentally.
Practical implications
The findings are applicable across diverse fields, including biomedical systems, heat exchanging devices, electronic cooling systems, food processing, drying processes, crystallization, mixing processes and beyond.
Originality/value
This work provides a novel exploration of CuO-water nanofluid flow in mixed convection within a grooved channel cavity under the influence of an inclined magnetic field. The influence of different heater positions on thermomagnetic convection in such a cavity has not been extensively investigated before, contributing to the originality and value of this research.
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Lee Elliot Major and Jennie Miles Weiner
The purpose of this paper is to argue that current ways school systems have addressed social mobility is misguided at best and, at worst, hurts social mobility. Instead, we call…
Abstract
Purpose
The purpose of this paper is to argue that current ways school systems have addressed social mobility is misguided at best and, at worst, hurts social mobility. Instead, we call for a focus on investment in teachers' professional capital as a primary lever for enhancing the likelihood they can effectively prepare and develop all children to lead successful lives after school. These arguments have become even more pertinent with the COVID-19 pandemic.
Design/methodology/approach
Using contemporary research, and grounded in our collective decades of research in these areas, we define social mobility and document how the aim of improving it has become a central tenet of our governments' stated ambitions and the yardstick by which school systems' success is measured. We then show how the application of market-based approaches to schools and teachers' work has hindered social mobility and offer a new path forward.
Findings
After 50 years of neoliberal policies incentivising individualistic and competitive behaviours, it is time to move towards policies that enhance professional capital and promote high quality collaboration between teachers. We call for a new path forward: a re-orientation to invest in teachers' capacity to realise the potential of education to improve the life prospects for all children, irrespective of their background.
Originality/value
As with so many issues, the COVID-19 pandemic has shone an intense light on the role of educators in society. There are credible concerns that economic and educational inequalities resulting from the crisis have the potential to trigger a fall in future social mobility levels. Yet this should also be seen as a new dawn for renewed thinking in which we seriously consider a shift away from neoliberal to professional capital policies to create an education system that nurtures teaching professionals, promotes collective behaviour and helps rather than hinders efforts to improve social mobility.
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Jill Theresa Messing, Jacquelyn C Campbell, Allison Ward-Lasher, Sheryll Brown, Beverly Patchell and Janet Sullivan Wilson
The purpose of this paper is to examine the differential use of the Lethality Assessment Program (LAP) – a risk-informed, collaborative police-social service intervention – across…
Abstract
Purpose
The purpose of this paper is to examine the differential use of the Lethality Assessment Program (LAP) – a risk-informed, collaborative police-social service intervention – across female victim-survivors of intimate partner violence (IPV) in four police jurisdictions in Oklahoma.
Design/methodology/approach
Women visited by the police during the study period participated in semi-structured telephone interviews. Logistic regression was utilized to examine what factors impacted implementation of the LAP.
Findings
There was differential use of the intervention based on the following: jurisdiction, severe violence at the incident, perpetrator’s use of a weapon ever in the relationship, PTSD symptomology, and women’s prior protective actions and utilization of domestic violence advocacy services.
Research limitations/implications
Future research should examine the decision-making process of survivors and police officers to better elucidate the meaning behind these statistical relationships.
Practical implications
PTSD education should be an integral part of police training on domestic violence. In addition, officers should be trained to recognize less injurious, but also damaging, forms of IPV, such as verbal abuse and coercive control.
Social implications
While police contact can provide accountability for the offender, the social service system is best equipped to provide safety options for the victim-survivor of violence.
Originality/value
Previous research has demonstrated the effectiveness of the LAP. It is important to understand how the intervention is applied in order to better understand who is most assisted by the intervention and what training or education could be beneficial for officers providing the intervention.
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Sahar A. Abbood and Bengt Ake Sunden
The purpose of this paper is to carry out a numerical investigation to study forced convection for a tube with fins on the inner and outer surfaces with water as the base fluid…
Abstract
Purpose
The purpose of this paper is to carry out a numerical investigation to study forced convection for a tube with fins on the inner and outer surfaces with water as the base fluid and adding particles of CuO to have a nanofluid.
Design/methodology/approach
Three geometries are designed by using Solid Works and the number of inside fins is 20 with height 6 mm and thickness 1 mm. The number of outside fins is 20 with height 12 mm and thickness 1 mm. The length of the tube is 1,000 mm and the inner and outer diameter is 26 and 28 mm, respectively. The annular diameter is 60 mm. The geometries are imported to Gambit where the mesh is chosen and the boundary conditions are specified. The commercial software package Fluent version 14.0 has been used to numerically solve the governing equations for the three cases.
Findings
The temperature contours for the three models at different air velocities, i.e., 5, 7.5 and 10 m/s and water velocities 0.8, 1 and 3 m/s have been investigated. The enhancement of heat transfer by using CuO nanoparticles has been investigated at different nanofluid concentrations.
Originality/value
In this paper, a numerical study is presented to analyze internal and external longitudinal finned tubes with water inside and air outside, with and without nano CuO particles.
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– The purpose of this paper is to underscore the importance of time and outline timeless tools to manage your time.
Abstract
Purpose
The purpose of this paper is to underscore the importance of time and outline timeless tools to manage your time.
Design/methodology/approach
The tools are gleaned from author's 32 years of practical experience in industry, teaching, training, research and consultancy. It explains the significance of time and elaborates with illustrations to manage your time.
Findings
The paper cautions that if you waste one second, you wasted one second of your life.
Research limitations/implications
Qualitative/action research inevitably needs to be backed up by more formal research into the topic. This paper offers an agenda for action and further qualitative/quantitative research in time management.
Practical implications
The timeless tools on time management can be applied in all areas of life such as personal, professional and social lives.
Social implications
These time-tested tools are essential for everybody to make a difference for themselves and also for others.
Originality/value
The paper enlightens that the biggest gift one can give to others is time, not money.
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