scholarly journals Determining Lower Bounds for Packing Densities of Non-layered Patterns Using Weighted Templates

10.37236/774 ◽  
2008 ◽  
Vol 15 (1) ◽  
Author(s):  
Cathleen Battiste Presutti
Keyword(s):  
Lower Bounds ◽  
Packing Density ◽  
Permutation Pattern ◽  
Maximum Proportion ◽  
Limiting Value ◽  
Packing Densities

The packing density of a permutation pattern $\pi$ is the limiting value, ${n}$ $\rightarrow$ $\infty$, of the maximum proportion of subsequences of $\sigma$ $\in$ ${S_{n}}$ that are order-isomorphic to $\pi$. We generalize methods for obtaining lower bounds for the packing density of any pattern and demonstrate the methods' usefulness when patterns are non-layered.

scholarly journals On Packing Densities of Permutations

10.37236/1622 ◽  
2002 ◽  
Vol 9 (1) ◽  
Author(s):  
M. H. Albert ◽  
M. D. Atkinson ◽  
C. C. Handley ◽  
D. A. Holton ◽  
W. Stromquist
Keyword(s):  
Lower Bounds ◽  
Maximum Density ◽  
Upper And Lower Bounds ◽  
Maximal Density ◽  
Permutation Pattern ◽  
Packing Densities

The density of a permutation pattern $\pi$ in a permutation $\sigma$ is the proportion of subsequences of $\sigma$ of length $|\pi|$ that are isomorphic to $\pi$. The maximal value of the density is found for several patterns $\pi$, and asymptotic upper and lower bounds for the maximal density are found in several other cases. The results are generalised to sets of patterns and the maximum density is found for all sets of length $3$ patterns.

scholarly journals Packing Densities of Patterns

10.37236/1833 ◽  
2004 ◽  
Vol 11 (1) ◽  
Author(s):  
Reid W. Barton
Keyword(s):  
Packing Density ◽  
Maximum Proportion ◽  
Packing Densities

The packing density of a permutation $\pi$ of length $n$ is the maximum proportion of subsequences of length $n$ which are order-isomorphic to $\pi$ in arbitrarily long permutations $\sigma$. For the generalization to patterns $\pi$ which may have repeated letters, two notions of packing density have been defined. In this paper, we show that these two definitions are equivalent, and we compute the packing density for new classes of patterns.

Lower bounds for packing densities

1991 ◽  
Vol 57 (3-4) ◽  
pp. 291-311 ◽  
Author(s):  
K. Bezdek ◽  
R. Connelly
Keyword(s):  
Lower Bounds ◽  
Packing Densities

Effect of Adding Stone Sludge as Sand Replacement on Fresh Properties of Mortar

2020 ◽  
Vol 984 ◽  
pp. 213-218
Author(s):  
Yong Xia ◽  
Jia Jian Chen ◽  
An Min Ma ◽  
Zi Hong Li
Keyword(s):  
Film Thickness ◽  
Packing Density ◽  
Fresh Properties ◽  
River Sand ◽  
Average Film Thickness ◽  
Density Results ◽  
Packing Densities

Shortage of river sand and disposal of stone sludge are the problem of the construction and stone product industries, respectively. Utilization of stone sludge in mortar is one of the feasible strategies to solve these two problems. To study the effects of addition of stone sludge on the performance of mortar, 20 mixes of stone sludge powder mortar with various water/cement ratios and various stone sludge powder contents were produced for flowability measurement. To further study the governing mechanism of flowability and the packing densities of the solid proportions of the 20 mortar mixes were measured. Based on the packing density results, the average film thickness (AFT) of the 20 mortar mixes were calculated for flowability indication. Results proved that addition of stone sludge powder as sand replacement would decrease the flowability. The flowability was mainly governed by the AFT.

scholarly journals POLOS PACKING DENSITY AND EFFECT OF RELATIVE BLOCK DENSITY

1978 ◽  
Vol 1 (16) ◽  
pp. 137
Author(s):  
J.A. Zwamborn
Keyword(s):  
Physical Properties ◽  
Packing Density ◽  
Model Tests ◽  
Test Results ◽  
Regular Waves ◽  
Shape Factors ◽  
Flume Tests ◽  
Testing Techniques ◽  
The Mean ◽  
Packing Densities

Accuracy and compatibility of measuring and testing techniques are discussed briefly and a plea is made for standardization to avoid, as far as possible, deviations in test results of different laboratories. One of the main causes of these differences is inconsistency in Dolos packing densities and corresponding layer thicknesses or shape factors. In an attempt to alleviate this problem three placing densities, namely 'light', 'mean' and 'dense' have been defined and their physical properties determined. Flume tests with regular waves, and Dolos armour units at these packing densities, showed very little difference in stability and, considering practical limitations during construction, it is suggested that the 'mean' packing density be used for a 'first design', followed by proper model tests. The results of tests with model Dolosse using three different unit densities were inconclusive and further tests using a wider range of densities are underway.

scholarly journals Drying Shrinkage and Cracking Tendency of Concrete Pavement Mixtures with Variable Packing Densities of Aggregates and Paste Contents

2020 ◽  
Vol 322 ◽  
pp. 01045
Author(s):  
Jan Olek ◽  
Adam Rudy
Keyword(s):  
Packing Density ◽  
Drying Shrinkage ◽  
Concrete Pavement ◽  
Concrete Mixture ◽  
Concrete Pavements ◽  
Saturation Ratio ◽  
Cracking Potential ◽  
Paste Content ◽  
Cracking Tendency ◽  
Packing Densities

Excessive drying shrinkage, and associated cracking, can lead to serious durability problem in concrete pavements and bridges. In the course of this study, the magnitude of drying shrinkage and cracking potential was evaluated for several concrete pavement mixtures as a function of packing density of the aggregate and paste contents. The results indicated that both, the shrinkage and the cracking potential depend on the volume of voids between aggregate particles (packing density), paste content of concrete mixture, and the paste-aggregate void saturation ratio.

scholarly journals Effect of packing density on selected tissue biochemical parameters of hatchery produced fingerlings of orange spotted grouper Epinephelus coioides (Hamilton, 1822) during transportaion

2018 ◽  
Vol 65 ◽  
Author(s):  
Biji Xavier ◽  
Sekar Megarajan ◽  
Ritesh Ranjan ◽  
Ponnaganti Shiva ◽  
Biswajit Dash ◽  
...  
Keyword(s):  
Water Quality ◽  
Packing Density ◽  
Biochemical Parameters ◽  
Ammonia Nitrogen ◽  
Quality Parameters ◽  
Water Quality Parameters ◽  
Epinephelus Coioides ◽  
Tissue Samples ◽  
Total Ammonia ◽  
Packing Densities

<p>Effect of different packing densities on water quality parameters, survival and selected tissue biochemical parameters during transportation of hatchery produced fingerlings of orange spotted grouper <em>Epinephelus coioides</em> (Hamilton, 1822) was investigated. Fingerlings (weight 3.0±0.2 g and length 6.0±0.2 cm) were packed in sealed double layered oxygen packed polythene bags (water and oxygen ratio 1:3) at different packing densities of 20, 30, 40 and 50 no. l-1. The packed fishes were transported for 6 h. After transportation, water samples and tissue samples from fishes were collected for further analyses. Levels of tissue glucose and selected metabolic enzymes (lactate dehydrogenase, LDH; aspartate amino transferase, AST and alanine amino transferase, ALT) significantly (p&lt;0.05) increased with increased packing density. Water quality parameters <em>viz.,</em> pH, dissolved oxygen, CO2, alkalinity, total ammonia nitrogen (TAN) and nitrite nitrogen (NO2-N) were also significantly different at higher packing densities (p&lt;0.05). However, levels of all the tissue biochemical parameters tested were in tolerable range and no mortality of fingerlings was recorded at any of the packing densities. Though the tissue enzyme levels were significantly higher and water quality was significantly deteriorated at the highest packing density of 50 no. l-1, it did not lead to mortality of fish. Therefore, it is inferred that this density can be used for short distance transportation of fingerlings of orange spotted grouper.</p>

scholarly journals Handling and Curing Characteristics of Cut-Strip Tobacco. Part 1: Effect of Strip-Size, Packing Density and Mode of Orientation

2002 ◽  
Vol 20 (1) ◽  
pp. 7-13
Author(s):  
WH Johnson ◽  
JH Young ◽  
GH Ellington ◽  
WW Weeks ◽  
JC Tutor
Keyword(s):  
Packing Density ◽  
Energy Use ◽  
Energy Savings ◽  
Reducing Sugars ◽  
Leaf Chemistry ◽  
Vertical Orientation ◽  
Leaf Quality ◽  
Horizontal Orientation ◽  
Total Alkaloids ◽  
Packing Densities

AbstractPrevious work has demonstrated potential handling and curing efficiencies in the use of cut-strip tobacco. The present work considers further the effect of cut-strip size, packing density and mode of orientation on cured leaf chemistry (starch, reducing sugars, and total alkaloids) and leaf quality. Results showed that cured leaf chemistry of 15.2 × 22.9 cm cut-strip more closely matched properties of whole leaf than pieces 15.2 × 15.2 cm or smaller. Starch contents were significantly higher for the smaller cut-strip sizes, perhaps due to edge drying effects, while alkaloids were significantly lower. Within the range of 194 to 292 kg/m, packing density had little effect on leaf chemistry, with the exception that reducing sugars were slightly lower for the higher packing densities. This could be due to a longer time for the drying front to move through the more tightly packed tobacco, and hence more respiratory loss of sugars. Government grades and average market prices of cured strips were essentially unaffected over the range of strip sizes or packing densities tested. Based on airflow resistance measurements and observed drying characteristics, vertical orientation of strips was far superior to horizontal orientation, both with vertical airflow through the tobacco. The higher packing density reduced specific energy use (kWh/kg green tobacco) by as much as 22%, indicating potential energy savings for cut-strip over whole leaf curing.

scholarly journals Numerical Investigation of Coil Configurations That Provide Ultrahigh Packing Density of Saccular Aneurysms

2009 ◽  
Vol 3 (4) ◽  
Author(s):  
Chander Sadasivan ◽  
Baruch B. Lieber
Keyword(s):  
Packing Density ◽  
Circular Cross Section ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Stable Configuration ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Coefficients Of Variation ◽  
Packing Densities

The long-term outcome of endovascular coiling of cerebral aneurysms is directly related to the packing density at the time of treatment. In general, the highest packing density achievable is only about 45% due to the quasirandom distribution of currently available coils within aneurysms. We investigated whether packing densities could be maximized via more ordered coil configurations. Three different coil configurations—circular loops, planar spirals, and spherical helices—were investigated. The packing densities achievable in maximally filling the volume of an exemplar human basilar aneurysm with each coil configuration were calculated numerically. Coil packing simulations were also carried out for aneurysms idealized as spheres over diameters ranging from 2 mm to 30 mm. The packing densities with the loop, spiral, and spherical helix configurations were 82%, 60%, and 73%, respectively, for the human aneurysm model; the numbers of coils required were 693, 34, and 13, respectively. Simulations within idealized aneurysms suggest that aneurysms cannot be packed to more than 91% with coils of constant circular cross section. The spherical helix configuration provides a constant packing density (coefficient of variation of 0.4%) over the range of aneurysm diameters studied as compared to the two other configurations (coefficients of variation of 9% and 8%). Coil configurations that allow for ordered filling of cerebral aneurysms can potentially provide packing densities that are twice those currently achieved. The spherical helix configuration seems to be the most technically feasible and stable configuration of the three coil types investigated.

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