Diffraction and bremsstrahlung radiation from a loop charge in a cylindrical pipe with a step change in wall radius

1989 ◽  
Vol 66 (1) ◽  
pp. 23-36 ◽  
Author(s):  
Robert A. Schill ◽  
S. R. Seshadri
Keyword(s):  
Step Change ◽  
Bremsstrahlung Radiation ◽  
Cylindrical Pipe

ON THE INTERACTION OF A VISCOELASTIC CYLINDRICAL PIPE WITH INNER UNIFORM COATING AND INSERTS WITH A COMPLEX PROFILE

2020 ◽  
Author(s):  
Kirill Kazakov
Keyword(s):  
Complex Shape ◽  
High Accuracy ◽  
Contact Stresses ◽  
Basis Functions ◽  
Complex Profile ◽  
Cylindrical Pipe ◽  
Interference Fit ◽  
Uniform Coating ◽  
Special Basis ◽  
Insert Region

This work is devoted to the formulation and construction of an analytical solution to the problem of contact between a cylindrical viscoelastic aging pipe with an internal thin coating and an insert having a complex shape placed inside the pipe with an interference fit. In practice, the presence of such coatings is required, for example, to protect the main structure from aggressive external or internal environments, for its electrical insulation, etc. The manufacturing process of the inner coating determines its possible heterogeneity (dependence of properties on coordinates). An insert placed inside a pipe can have a complex profile that has a rapidly changing function. Taking these features into account is important when analyzing the stress-strain state of pipes with an internal coating. Using an approach based on the use of special basis functions and the type of solution, a representation for the contact stresses in the pipe in the region of the rigid insert is obtained. This approach makes it possible to distinguish functions that describe the properties of the inner coating and the shape of the outer profile of the insert in the form of separate terms and factors in the expression for the contact stresses in the insert region. Therefore, in order to achieve high accuracy when carrying out calculations, it is sufficient to restrict ourselves to a relatively small number of terms

GREEN refining technology

2015 ◽  
pp. 508-514 ◽  
Author(s):  
Craig Jensen ◽  
David Love
Keyword(s):  
Environmentally Friendly ◽  
Step Change ◽  
Energy Usage ◽  
Capital Equipment ◽  
Green Is ◽  
Cooling Crystallization ◽  
Sugar Refinery

The objective of this paper is to describe a “step-change” in refining technology being proposed by Tongaat Hulett. This patented technology is termed “GREEN” Refining Technology, where “GREEN” is an acronym for “Greatly Reduced Energy and Equipment Needs”. The name attempts to encapsulate the “environmentally friendly” benefits of reduced energy usage whilst also emphasising the major savings in both energy and capital equipment requirements of the technology. GREEN refining technology aims to substantially (and ultimately totally) replace evaporating crystallization with cooling crystallization in a sugar refinery.

MSDGC, CH2M, and Qualcomm Technologies, Inc. Work Together to Create Step Change in Asset Management Technology

2016 ◽  
Vol 2016 (1) ◽  
pp. 722-733
Author(s):  
Elizabeth S Kelly ◽  
Verna Arnette ◽  
Scott Maring ◽  
Ken Thompson ◽  
Chris Macintosh
Keyword(s):  
Asset Management ◽  
Step Change ◽  
Management Technology

Has the SARS-CoV-2 outbreak had an impact on uptake of digital cessation support in UK smokers? An interrupted time series analysis (Preprint)

2020 ◽  
Author(s):  
Olga Perski ◽  
Aleksandra Herbec ◽  
Lion Shahab ◽  
Jamie Brown
Keyword(s):  
Time Series ◽  
Smoking Cessation ◽  
Secondary Analysis ◽  
Interrupted Time Series ◽  
Step Change ◽  
Outcome Variable ◽  
Primary Analysis ◽  
Increasing Trend ◽  
The Uk ◽  
Temporary Closure

BACKGROUND The SARS-CoV-2 outbreak may motivate smokers to attempt to stop in greater numbers. However, given the temporary closure of UK stop smoking services and vape shops, smokers attempting to quit may instead seek out digital support, such as websites and smartphone apps. OBJECTIVE We examined, using an interrupted time series approach, whether the SARS-CoV-2 outbreak has been associated with a step change or increasing trend in UK downloads of an otherwise popular smoking cessation app, Smoke Free. METHODS Data were from daily and non-daily adult smokers in the UK who had downloaded the Smoke Free app between 1 January 2020 and 31 March 2020 (primary analysis) and 1 January 2019 and 31 March 2020 (secondary analysis). The outcome variable was the number of downloads aggregated at the 12-hourly (primary analysis) or daily level (secondary analysis). The explanatory variable was the start of the SARS-CoV-2 outbreak, operationalised as 1 March 2020 (primary analysis) and 15 January 2020 (secondary analysis). Generalised Additive Mixed Models adjusted for relevant covariates were fitted. RESULTS Data were collected on 45,105 (primary analysis) and 119,881 (secondary analysis) users. In both analyses, there was no evidence for a step change or increasing trend in downloads attributable to the start of the SARS-CoV-2 outbreak. CONCLUSIONS In the UK, between 1 January 2020 and 31 March 2020, and between 1 January 2019 and 31 March 2020, there was no evidence that the SARS-CoV-2 outbreak has been associated with a surge in downloads of a popular smoking cessation app. CLINICALTRIAL osf.io/zan2s

scholarly journals The Carnot Cycle, Reversibility and Entropy

Entropy ◽  
2021 ◽  
Vol 23 (7) ◽  
pp. 810
Author(s):  
David Sands
Keyword(s):  
Irreversible Process ◽  
Entropy Change ◽  
External Pressure ◽  
Step Change ◽  
Equilibrium States ◽  
Rate Equations ◽  
Carnot Cycle ◽  
Work Processes ◽  
Reversible Process ◽  
External Conditions

The Carnot cycle and the attendant notions of reversibility and entropy are examined. It is shown how the modern view of these concepts still corresponds to the ideas Clausius laid down in the nineteenth century. As such, they reflect the outmoded idea, current at the time, that heat is motion. It is shown how this view of heat led Clausius to develop the entropy of a body based on the work that could be performed in a reversible process rather than the work that is actually performed in an irreversible process. In consequence, Clausius built into entropy a conflict with energy conservation, which is concerned with actual changes in energy. In this paper, reversibility and irreversibility are investigated by means of a macroscopic formulation of internal mechanisms of damping based on rate equations for the distribution of energy within a gas. It is shown that work processes involving a step change in external pressure, however small, are intrinsically irreversible. However, under idealised conditions of zero damping the gas inside a piston expands and traces out a trajectory through the space of equilibrium states. Therefore, the entropy change due to heat flow from the reservoir matches the entropy change of the equilibrium states. This trajectory can be traced out in reverse as the piston reverses direction, but if the external conditions are adjusted appropriately, the gas can be made to trace out a Carnot cycle in P-V space. The cycle is dynamic as opposed to quasi-static as the piston has kinetic energy equal in difference to the work performed internally and externally.

Associations between life-course frailty and later-life heart size and function in the 1946 NSHD British birth cohort-an epidemiological study

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C.C Topriceanu ◽  
J.C Moon ◽  
R Hardy ◽  
A.D Hughes ◽  
N Chaturvedi ◽  
...  
Keyword(s):  
Life Course ◽  
Birth Cohort ◽  
Frailty Index ◽  
Later Life ◽  
Left Ventricular ◽  
Step Change ◽  
Deficit Accumulation ◽  
Heart Size ◽  
And Function ◽  
The Life Course

Abstract Background Cardiovascular diseases are an important component of the multi-morbidity syndrome which is associated with negative health outcomes resulting in a major societal economic burden. An objective way to assess multi-morbidity is to calculate a frailty index based on medical deficit accumulation. Late-life frailty has been validated to predict mortality, but little is known about the association between life-course frailty and cardiovascular health in later-life. Purpose To study the association between life-course frailty and later-life heart size and function using data from the world's longest running birth cohort with continuous follow-up. Methods A 45-deficit frailty index (FI) was calculated at 4 age-intervals across the life-course (0 to 16 years old, 19 to 44 years old, 45 to 54 years old and 60 to 64 years old) in participants from the UK 1946 Medical Research Council (MRC) National Survey of Heath and Development (NSHD) birth cohort. The life-course frailty indices (FI0_16, FI19_44, FI45_54 and FI60_64) reflect the cumulative medical deficits at the corresponding age-intervals. They were used to derive FImean and FIsum reflecting overall-life frailty. The step change in deficit accumulation between age-intervals was also calculated (FI2-1, FI3-1, FI4-1, FI3-2, FI4-2, FI4-3). Echocardiographic data at 60–64 years provided: E/e' ratio, ejection fraction (EF), myocardial contraction fraction index (MCFi) and left ventricular mass index (LVmassi). Generalized linear mixed models with gamma distribution and log link assessed the association between FIs and echo parameters after adjustment for sex, socio-economic position and body mass index. Results 1.805 NSHD participants were included (834 male). Accumulation of a single deficit had a significant impact (p<0.0001 to p<0.049) on LVmassi and MCFi in all the life-course FIs and overall FIs. LVmassi increased by 0.89% to 1.42% for the life-course FIs and by 0.36%/1.82% for FIsum and FImean respectively. MCFi decreased by 0.62% to 1.02% for the life-course FIs and by 0.33%/ 1.04%. for FIsum and FImean respectively. One accumulated deficit translated into higher multiplicative odds (13.2 for FI60-64, 2.1 for FI4-1, 75.4 for FI4-2 and 78.5 for FI4-3) of elevated filling pressure (defined as E/e' ratio >13, p<0.0.005 to p<0.02).A unit increase in frailty decreased LV EF (%) by 11%/12% for FI45-54 and FI60-64 respectively, by 10% to 12% for FI2-1, FI3-1, FI4-1 and FI4-2, and 4%/15% for FIsum and FImean respectively (p<0.0014 to p<0.044). Conclusion Frailty during the life-course, overall life-frailty and the step change in deficit accumulation is associated with later-life cardiac dysfunction. Frailty strain appears to have its greatest impact on pathological myocardial hypertrophy (high LVmassi and low MCFi) potentially paving the way to later-life systolic or diastolic dysfunction in susceptible individuals. Funding Acknowledgement Type of funding source: None

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