scholarly journals Clustering for Different Scales of Measurement - The Gap Ratio Weighted K-Means Algorithm

2017 ◽  
Author(s):  
Joris Guerin ◽  
Olivier Gibaru ◽  
Stephane Thiery ◽  
Eric Nyiri
Keyword(s):  
Gap Ratio ◽  
Scales Of Measurement

scholarly journals Coherent Superconductivity with a Large Gap Ratio from Incoherent Metals

2018 ◽  
Vol 121 (18) ◽  
Author(s):  
Aavishkar A. Patel ◽  
Michael J. Lawler ◽  
Eun-Ah Kim
Keyword(s):  
Gap Ratio

scholarly journals Depth of poverty in an informal settlement in the Vaal region, South Africa

2010 ◽  
Vol 15 (1) ◽  
Author(s):  
Wilna Oldewage-Theron ◽  
Tielman J.C. Slabbert
Keyword(s):  
Informal Settlement ◽  
Sub Saharan Africa ◽  
Community Based Interventions ◽  
Urban Food Security ◽  
Gap Ratio ◽  
Sub Saharan ◽  
Poverty Indicators ◽  
Sustainable Income ◽  
The Impact ◽  
Measurement Of Poverty

Despite the large number of people currently living in poverty in sub-Saharan Africa, the debate about the definition and meaning of poverty continues. Two distinct problems exist regarding the measurement of poverty, namely the difficulty of identifying the poor in a population and the difficulty in developing an index for the measurement of poverty. The main objective of the survey was to apply a poverty model for determining the depth of poverty in an informal settlement in the Vaal Region, as well as the impact of possible income-generating activities on the community. A questionnaire, which had been devised for measuring poverty indicators, was administered to 429 randomly selected households in the informal settlement, with the poverty model being applied to measure the degree of poverty. The results of the survey showed that 286 households lived in poverty at the time. The impact of extra income on the poverty levels of these 286 households was then determined. The results of the survey also showed that the unemployment level was 91% and that the mean monthly income was R612.50. The average poverty gap was R1017.21, with the poverty gap ratio being 56%. The poverty model showed that an increase of R500 in monthly household income resulted in a poverty gap ratio of 35%. The results indicated that the community was a poverty-stricken community, suffering from chronic food insecurity. The results of the study will be used to facilitate the planning and implementation of sustainable, income-generating, community-based interventions aimed at promoting urban food security and alleviating poverty in the community in question. OpsommingTen spyte van die groot hoeveelheid mense wat steeds wêrelwyd in armoede leef, duur die debat oor die definisie en betekenis van armoede nog altyd voort. Daar word twee definitiewe probleme met die meting van armoede ervaar, naamlik die identifisering van die armes in 'n gemeenskap, en die ontwikkeling van 'n indeks vir die meet van armoede. Die hoofdoel van hierdie studie was om 'n armoedemodel vir die dieptemeting van armoede in 'n informele nedersetting in die Vaal-area toe te pas, en om die impak van moontlike aktiwiteite wat inkomste genereer in dieselfde gemeenskap te bepaal. 'n Vraelys wat ontwerp is om armoede aan te dui en te meet is ewekansig aan 429 huishoudings in die informele nedersetting uitgedeel om te voltooi en die armoedemodel is toegepas om die diepte van armoede te meet. Die resultate het getoon dat 286 huishoudings in armoede leef. Die impak van ekstra inkomste op armoedevlakke is in die 286 huishoudings bepaal. Die resultate het verder getoon dat die werkloosheidsvlak 91% was en dat die gemiddelde maandelikse huishoudelike inkomste R612.50 was. Die gemiddelde armoedegaping was R1017.21, met 'n armoedegapingverhouding van 56%. Die armoedemodel het getoon dat 'n verhoging van R500 in maandelikse huishoudelike inkomste die armoedegapingverhouding na 35% verlaag het. Die resultate het bewys dat hierdie 'n armoedige gemeenskap met kroniese voedselonsekerheid was. Die uitkoms van die studie sal gebruik word vir die beplanning en implementering van gemeenskapgebaseerde ingrypings om volhoubare inkomste te genereer om stedelike voedselsekerheid te bevorder en die armoede in hierdie gemeenskap te verlig.

scholarly journals Effect of Cylinder Gap Ratio on The Wake of a Circular Cylinder Enclosed by Various Perforated Shrouds

CFD letters ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 51-68
Author(s):  
Nurul Azihan Ramli ◽  
Azlin Mohd Azmi ◽  
Ahmad Hussein Abdul Hamid ◽  
Zainal Abidin Kamarul Baharin ◽  
Tongming Zhou
Keyword(s):  
Reynolds Number ◽  
Circular Cylinder ◽  
Vortex Shedding ◽  
Control Method ◽  
Lift Coefficient ◽  
Base Case ◽  
Bluff Bodies ◽  
Ansys Fluent ◽  
Gap Ratio ◽  
Spacing Ratio

Flow over bluff bodies produces vortex shedding in their wake regions, leading to structural failure from the flow-induced forces. In this study, a passive flow control method was explored to suppress the vortex shedding from a circular cylinder that causes many problems in engineering applications. Perforated shrouds were used to control the vortex shedding of a circular cylinder at Reynolds number, Re = 200. The shrouds were of non-uniform and uniform holes with 67% porosity. The spacing gap ratio between the shroud and the cylinder was set at 1.2, 1.5, 2, and 2.2. The analysis was conducted using ANSYS Fluent using a viscous laminar model. The outcomes of the simulation of the base case were validated with existing studies. The drag coefficient, Cd, lift coefficient, Cl and the Strouhal number, St, as well as vorticity contours, velocity contours, and pressure contours were examined. Vortex shedding behind the shrouded cylinders was observed to be suppressed and delayed farther downstream with increasing gap ratio. The effect was significant for spacing ratio greater than 2.0. The effect of hole types: uniform and non-uniform holes, was also effective at these spacing ratios for the chosen Reynolds number of 200. Specifically, a spacing ratio of 1.2 enhanced further the vortex intensity and should be avoided.

scholarly journals A numerical study of free convective heat transfer within domed skylight cavities

2021 ◽  
Author(s):  
AmirAbbas Sartipi
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Numerical Study ◽  
Control Volume ◽  
Energy Performance ◽  
Vortex Cell ◽  
Design Elements ◽  
Gap Ratio

Domed skylights are important architectural design elements to deliver daylight and solar heat into buildings and connect buildings' occupants to outdoors. To increase the energy efficiency of skylighted buildings, domed skylights employ a number of glazing layers forming enclosed spaces. The latter are subject to complex buoyancy-induced convection heat transfer. Currently, existing fenestration design computer tools and building energy simulation programs do not, however, cover such skylights to quantify their energy performance when installed in buildings. his work presents a numerical study on natural laminar convection within concentric and vertically eccentric domed cavities. The edges of domed cavities are assumed adiabatic and the temperature of the interior and exterior surfaces are uniform and constant. The concentric and vertically eccentric domed cavities were studied when heated from inside and heated from outside, respectively. A commercial CFD package employing the control volume approach is used to solve the laminar convective heat transfer within the cavity. The obtained results showed steady flow for small Grashof numbers. For moderate and large Grashof numbers, depending on the gap ratio and the cases of heating from inside or outside, the flow may be steady or transient periodic with a single vortex-cell or multi vortex-cells. The Nusselt number for the case of heated from inside is greater than the case of heated from outside. The numerical results show that the changes in the gap ratio have smaller effect on Nusselt number in high profile domed skylights than lower profile domed skylights.

The crown-gap ratio (C) and crown cover: The field study

1988 ◽  
Vol 13 (1) ◽  
pp. 101-108 ◽  
Author(s):  
J. WALKER ◽  
P. F. CRAPPER ◽  
L. K. PENRIDGE
Keyword(s):  
Field Study ◽  
Crown Cover ◽  
Gap Ratio

Analysis of the characteristics of air–yarn coupling movement in the profiled reed groove of an air-jet loom

2021 ◽  
pp. 004051752110569
Author(s):  
Yuzhen Jin ◽  
Hailang Xiong ◽  
Jingyu Cui
Keyword(s):  
Numerical Results ◽  
Weft Yarn ◽  
Valuable Insight ◽  
Arbitrary Lagrangian Eulerian ◽  
Air Jet ◽  
Gap Ratio ◽  
Gas Consumption ◽  
Simulation Results ◽  
Gas Leaks ◽  
Air Jet Loom

The movement characteristics of yarn in the profiled reed groove of an air-jet loom can have a great impact on the performance of the fabric. Unstable yarn movement tends to lead to weft defects, as short wefts or weft breaks may occur, which could deteriorate the quality of the final fabric. In this paper, the characteristics of the yarn movement in a profiled reed groove are numerically studied. The arbitrary Lagrangian–Eulerian method is used to solve the two-way airflow–yarn interaction and the yarn is simulated with the ball–socket model. A fluctuation ratio is defined to characterize the unsteadiness of the yarn movement. Our simulation first investigates the effect of the gap ratio of the profiled reed groove (β) on the yarn movement then compares the movements of different yarn kinds. The simulation results indicate that a larger β not only decreases gas leaks (thus saves gas consumption), but also stabilizes the yarn movement. Our simulation results also show that the movement of the yarn of polypropylene is more stable than the other two weft-yarn materials. An experiment is also conducted to validate our numerical results, which shows a favorable agreement between them. Our numerical results of the yarn movement in the profiled reed groove can provide a valuable insight into the optimization of the weft insertion system of the air-jet loom.

Scales of Measurement

2018 ◽  
pp. 16-20
Author(s):  
Fred Pyrczak ◽  
Deborah M. Oh
Keyword(s):  
Scales Of Measurement

Measurement Essentials in a Nutshell

2020 ◽  
pp. 46-48
Author(s):  
Louis Narens ◽  
Brian Skyrms
Keyword(s):  
Scales Of Measurement ◽  
Interval Ratio

A quick introduction to scales of measurement, ordinal, interval, ratio, and absolute, and related issues of meaningfulness as invariance.

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