The Beverton–Holt q-Difference Equation with Periodic Growth Rate

2015 ◽  
pp. 3-14 ◽  
Author(s):  
Martin Bohner ◽  
Sabrina H. Streipert
Keyword(s):  
Growth Rate ◽  
Difference Equation ◽  
Periodic Growth

Evaluation on Application of Artificial Soil Made by Organic Wastes

2010 ◽  
Vol 658 ◽  
pp. 296-299
Author(s):  
Yeong Seok Yoo ◽  
Ho Jun Chae ◽  
Hyo Jin Ban ◽  
Eun Zoo Park
Keyword(s):  
Growth Rate ◽  
Sewage Sludge ◽  
Specific Gravity ◽  
Bulk Density ◽  
Adsorption Capacity ◽  
Leaf Growth ◽  
Volatile Matter ◽  
Artificial Soil ◽  
Natural Soil ◽  
Periodic Growth

Natural soil would be used for planting on paved area ground, but it had been replaced by the light weighted artificial soil to minimize burden of the structure. But, the existing light weighted soil had nearly capacity of fertilizer adsorption due to its glassy surface. In this study, the artificial soil prepared by sewage sludge was manufactured, tested characteristics as soil and examined on planting. The developed soil was analyzed through specific gravity, pH, water content, volatile matter and was tested on adsorption capacity of Cu. In addition, planting examination analyzed the leaf growth of planting and mouseear cress plant's pollen. As the result, the developed artificial soil showed to be color yellowish brown, bulk density 0.6g/cm3, pH 8~9, volatile matter 0.3, CEC 10, pressure strength 25 ton/m2, hydrophilic and non-toxic, which was suitable for rooftop gardening. Also, periodic growth rate and development of leaves was satisfactory as natural soil and growth and numbers of pollens were good. Consequently, the developed artificial soil with porosity and capacity of fertilizer adsorption could be usefully applicable to planting on the paved area.

scholarly journals Coupe préparatoire et croissance en surface terrière d'une sapiniére de seconde venue à la forêt modèle du Bas-Saint-Laurent, Québec

2001 ◽  
Vol 77 (4) ◽  
pp. 685-695 ◽  
Author(s):  
Richard Zarnovican ◽  
Jean-Martin Lussier ◽  
Claude Laberge
Keyword(s):  
Growth Rate ◽  
Relative Size ◽  
Basal Area ◽  
Balsam Fir ◽  
Basal Area Growth ◽  
Periodic Growth ◽  
Area Growth ◽  
Crown Characteristics ◽  
Highly Correlated ◽  
The Impact

Balsam fir basal area growth was studied 5 years after the preparatory cut in the context of natural regeneration by the shelterwood system. The study was carried out in a 60-year-old second-growth balsam fir-yellow birch stand. The felling trials were realized in 16 plots and consisted of control and three felling regimes (15, 30 and 45% of removed basal area). The periodic (5 years) mean growth rate on dbh of trees in plots varies between 6 and 12% in response to felling intensity. The basal area of plots presents a mean periodic growth rate of 7.4% independently of felling intensity. There are highly significant correlations between the live crown characteristics and periodic basal area growth. This growth is highly correlated with inital diameter and intensity of felling. The trees of higher relative size are more productive than the others and the impact of felling on periodic basal area growth is significant when the intensity of felling is greater than 30%. Conversely, the ratio between periodic basal area growth after treatment and periodic basal area growth before treatment is correlated only with the intensity of felling. Finally, intensity of felling had no effect on periodic basal area growth per square meter of crown projected area. Key words: preparatory felling, basal area growth, balsam fir

A Sensitivity Analysis of Deriso's Delay-Difference Equation Using Simulation

1985 ◽  
Vol 42 (4) ◽  
pp. 836-841 ◽  
Author(s):  
Albert V. Tyler ◽  
Linda L. Sebring ◽  
Margaret C. Murphy ◽  
Lea F. Murphy
Keyword(s):  
Growth Rate ◽  
Sensitivity Analysis ◽  
Mortality Rate ◽  
Difference Equation ◽  
Class Structure ◽  
Delay Difference Equation ◽  
Age Class ◽  
True Value ◽  
Two Parameters ◽  
Delay Difference

The degree to which the delay-difference equation can track biomass changes of fish stocks was examined using a sensitivity analysis technique in conjunction with a simulation model having explicit age-class structure. The simplicity of the delay-difference equation results from the manner in which it subsumes age-class structure by using two parameters, one for mortality and one for growth. The changes in biomass in a simulated stock were followed closely by the equation when error-free determinations of stock parameters were transferred from the simulated stock to the equation, even when a high degree of density dependence was allowed in the growth rate, and in some cases when there were large differences in age-specific mortality in the simulated stock. When error was induced in the stock parameters, the delay-difference equation was fairly robust in estimating biomass with mortality rate and growth rate simultaneously either above the true value or below the true value. Good biomass estimates also resulted when growth rate was at the true value and mortality rate was above the true value. Poor biomass estimates resulted when mortality was overestimated while growth was underestimated, or vice versa.

Mechanism relating cambial electrical resistance to periodic growth rate of balsam fir

1983 ◽  
Vol 13 (3) ◽  
pp. 472-480 ◽  
Author(s):  
Robert O. Blanchard ◽  
Walter C. Shortle ◽  
Weston Davis
Keyword(s):  
Growth Rate ◽  
New Hampshire ◽  
Electrical Resistance ◽  
Spruce Budworm ◽  
Probable Mechanism ◽  
Potassium Content ◽  
Balsam Fir ◽  
Periodic Growth ◽  
Cambial Zone

Cambial electrical resistance (CER) and periodic growth rate (PGR) of canopy balsam fir (Abiesbalsamea L.) trees were determined on 26 sites in Maine, New Hampshire, and Vermont, U.S.A., varying in level of spruce budworm defoliation. Determinations of water and potassium concentrations were made of the bark, wood, and vascular cambial zone (VCZ). Low CER was associated with high PGR and vice versa. A decline in PGR on all 26 sites was detected during early 1970's to late 1970's. It was not associated with, but may have been exacerbated by, spruce budworm defoliation. The most probable mechanism relating CER to PGR in balsam fir was variation in the thickness of VCZ and its correlation with potassium content. Thicker VCZ of faster growing trees released more potassium into the solution contacting electrodes than thinner VCZ of slower growing trees.

1.3 νm InAs/GaAs Quantum Dots Directly CappedWith GaAs Grown By Metal Organic Chemical Vapor Deposition

2003 ◽  
Vol 775 ◽  
Author(s):  
K.F. Huang ◽  
T.P. Hsieh ◽  
N.T. Yeh ◽  
W.J. Ho ◽  
J.I. Chyi ◽  
...  
Keyword(s):  
Growth Rate ◽  
Quantum Dots ◽  
Chemical Vapor Deposition ◽  
Growth Temperature ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Peak Wavelength ◽  
Room Temperature Photoluminescence ◽  
Periodic Growth

AbstractSystematic studies of the growth temperature and growth rate effect of the formation of InAs/GaAs quantum dots (QDs) have been demonstrated. These QDs are formed with large InAs coverage (3.0 MLs) and periodic growth interruption via Strnski-Krastonov (S-K) epitaxial growth mode by using metalorganic chemical vapor deposition (MOCVD). The room temperature photoluminescence (PL) spectra show red-shift of peak wavelength by decreasing the InAs growth temperature from 540°C to 500°C. As growth rate increases from 0.05 ML/s to 0.2 ML/s at growth temperature of 500°C, PL linewidth could be narrowed and emission intensity could be increased. These results could be correlated to the In clusters and uniformity of InAs/GaAs QDs observed by scanning electron microscopy (SEM) image. Finally, the room temperature photoluminescence spectra of InAs/GaAs QDs directly capped with GaAs shows peak wavelength of 1.35 μm with narrow linewidth of 30.8 meV is obtained.

The threshold energy for atom displacement in fcc metals

1990 ◽  
Vol 48 (4) ◽  
pp. 530-531
Author(s):  
Wilfried Sigle ◽  
Matthias Hohenstein ◽  
Alfred Seeger
Keyword(s):  
Growth Rate ◽  
Elevated Temperatures ◽  
Threshold Energy ◽  
Dislocation Loops ◽  
Absolute Minimum ◽  
Voltage Electron ◽  
Atom Displacement ◽  
Electron Microscopes ◽  
Fcc Metal

Prolonged electron irradiation of metals at elevated temperatures usually leads to the formation of large interstitial-type dislocation loops. The growth rate of the loops is proportional to the total cross-section for atom displacement,which is implicitly connected with the threshold energy for atom displacement, Ed . Thus, by measuring the growth rate as a function of the electron energy and the orientation of the specimen with respect to the electron beam, the anisotropy of Ed can be determined rather precisely. We have performed such experiments in situ in high-voltage electron microscopes on Ag and Au at 473K as a function of the orientation and on Au as a function of temperature at several fixed orientations.Whereas in Ag minima of Ed are found close to <100>,<110>, and <210> (13-18eV), (Fig.1) atom displacement in Au requires least energy along <100>(15-19eV) (Fig.2). Au is thus the first fcc metal in which the absolute minimum of the threshold energy has been established not to lie in or close to the <110> direction.

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