scholarly journals On stress integration of coupled viscodamage-viscoplasticity models with separate yield/loading surfaces

2018 ◽  
Vol 51 (3) ◽  
pp. 1-14 ◽  
Author(s):  
Timo Saksala
Keyword(s):  
Numerical Integration ◽  
Traditional Method ◽  
Corner Point ◽  
Internal Variables ◽  
Consistency Model ◽  
Specific Loading ◽  
Stress Integration ◽  
The One ◽  
Inelastic Strains ◽  
Nonstandard Method

This paper deals with numerical integration of stresses, inelastic strains and internal variables related to coupled viscodamage-viscoplasticity models. The class of models considered here is the one where the viscodamage and viscoplasticity parts are described independently based on their specific loading/yield criteria and evolutions laws. Moreover, in the viscodamage part, an anisotropic compliance damage formulation is adopted. Both the viscodmage and the viscoplasticity components are formulated in terms of the consistency model by Wang (1997). Two methods for coupling the damage and the plasticity parts are presented. In the first more traditional method, both models are solved simultaneously returning the trial stress onto the intersection of the criteria while updating the internal variables. The second, nonstandard method exploits the damage strain to impose iteratively the stress equality on the stress vectors returned independently on the respective, viscodamage and viscoplasticity surfaces. A special emphasis is laid on the treatment of the corner point plasticity case. After the general treatment, the two methods are illustrated with an application to the Mohr-Coulomb viscoplasticity model combined with Rankine viscodamage model.    

A TWELFTH-ORDER FOUR-STEP FORMULA FOR THE NUMERICAL INTEGRATION OF THE ONE-DIMENSIONAL SCHRÖDINGER EQUATION

2003 ◽  
Vol 14 (08) ◽  
pp. 1087-1105 ◽  
Author(s):  
ZHONGCHENG WANG ◽  
YONGMING DAI
Keyword(s):  
Schrödinger Equation ◽  
Numerical Integration ◽  
Schrodinger Equation ◽  
Numerical Test ◽  
New Method ◽  
Step Method ◽  
One Dimensional ◽  
The Stability ◽  
The One ◽  
Order Four

A new twelfth-order four-step formula containing fourth derivatives for the numerical integration of the one-dimensional Schrödinger equation has been developed. It was found that by adding multi-derivative terms, the stability of a linear multi-step method can be improved and the interval of periodicity of this new method is larger than that of the Numerov's method. The numerical test shows that the new method is superior to the previous lower orders in both accuracy and efficiency and it is specially applied to the problem when an increasing accuracy is requested.

scholarly journals Impact of Energy Slope Averaging Methods on Numerical Solution of 1D Steady Gradually Varied Flow

2015 ◽  
Vol 62 (3-4) ◽  
pp. 101-119 ◽  
Author(s):  
Wojciech Artichowicz ◽  
Dzmitry Prybytak
Keyword(s):  
Numerical Methods ◽  
Numerical Solution ◽  
Numerical Integration ◽  
Cross Sections ◽  
Flow Model ◽  
One Dimensional ◽  
Averaging Methods ◽  
Integration Formulas ◽  
Different Types ◽  
The One

AbstractIn this paper, energy slope averaging in the one-dimensional steady gradually varied flow model is considered. For this purpose, different methods of averaging the energy slope between cross-sections are used. The most popular are arithmetic, geometric, harmonic and hydraulic means. However, from the formal viewpoint, the application of different averaging formulas results in different numerical integration formulas. This study examines the basic properties of numerical methods resulting from different types of averaging.

Harvesting sugar-beet seed

1974 ◽  
Vol 83 (3) ◽  
pp. 435-442 ◽  
Author(s):  
P. C. Longden
Keyword(s):  
Sugar Beet ◽  
Size Distribution ◽  
Plant Height ◽  
Seed Yield ◽  
Traditional Method ◽  
Germination Percentage ◽  
Viable Seed ◽  
Chlormequat Chloride ◽  
Seed Crop ◽  
The One

SummaryComparisons of the effects of harvesting sugar-beet seed by the traditional method of tripodding with barn drying, swathing followed by threshing with a pick-up combine or desiccation with diquat followed by direct combine harvesting showed that there were no consistent or large effects on seed yield, germination, monogermity or size distribution. Thus the best method will be the one which is easiest and/or cheapest, which at present is swathing followed by pick-up combine threshing.Sprays of NAA or 2,4,5-T at 10 or 100 mg a.i./l water before or after flowering had no effect on seed yield or germination and efforts to restrict the loss by shedding of large viable seed failed. Neither chemical decreased germination percentage by setting parthenocarpic seed. Attempts were made to dwarf the 2 m high seed crop to make it suitable for direct combine harvesting. Daminozide sprayed at 1000, 5000 or 10000 mg a.i./l water before or after the winter did not affect plant height, seed yield, germination, monogermity or size distribution. Chlormequat chloride applied similarly dwarfed plants by up to 18% but this was not enough to give a crop less than 1 m high suitable for direct combine harvesting. It did not affect seed yield, germination, monogermity or size distribution. Ethephon sprayed at 10, 100 or 1000 mg a.i./l water when plants were bolting had no detected effects. Chlorflurecolmethyl was sprayed at 10 or 100 before bolting or 1, 10 or 100 mg a.i./l water afterwards. Plants sprayed with the 100 mg/1 solution were dwarfed to less than 1 m high but the treatment was unsuccessful because it greatly reduced seed yield and germination; monogermity was not affected but a much greater proportion of seed fell into the small size grades.

scholarly journals COMPARATIVE ANALYSIS OF THE EFFECTIVENESS OF CHRONOTHERAPY AND TRADITIONAL METHOD OF ALOPECIA AREATA TREATMENT

2017 ◽  
Vol 5 ◽  
pp. 31-37
Author(s):  
Nikolay Polischuk ◽  
Ilya Polischuk
Keyword(s):  
Alopecia Areata ◽  
Traditional Method ◽  
Hair Growth ◽  
Treatment Effectiveness ◽  
Clinical Effectiveness ◽  
Control Group ◽  
Working Ability ◽  
Traditional Treatment ◽  
The World ◽  
The One

Alopecia areata – is the one of widespread baldness forms, difficultly subjected to treatment. The method of chronotherapy that gains an essential circulation in Ukraine and throughout the world may play the important role in its solution. Aim: to study the clinical effectiveness of chronotherapy for alopecia areata treatment. Materials and methods. For attaining the set aim 108 persons with the diagnosis alopecia areata were examined and treated. Patients were divided in two groups. The main group included 45 persons – treated using the method of chronotherapy. The control group consisted of 67 persons, who received the traditional treatment of alopecia areata. The series of clinical, biochemical and immunological studies, directed on the assessment of the treatment effectiveness, were realized. Results. The treatment of patients with alopecia areata by the method of chronotherapy is statistically reliably more effective than the traditional treatment of this pathology and provides the renewal of hair growth in 53,3 % of patients that is accompanied by normalization of alexin, sulfhydryl groups content, acid phosphatase activity, serine, asparagine acid, valine, threonine, alanine, cystine, leucine, isoleucine concentrations. The offered chronotherapy method has the expressed anabolic effect on patients’ organism. The menstrual cycle is normalized, pre-menstrual syndrome symptoms and aldodysmenorrhea disappear, patients’ working ability and state of health improve. Conclusions. The obtained data deepen knowledge about the pathogenesis of alopecia areata at the biochemical and immunological levels and favor the rise of the effectiveness of diagnostics and treatment of this pathology. At the study the high chronotherapy effectiveness at treating alopecia areata was revealed and the possibility of its use for the effective treatment of a series of other pathologies was proved.

scholarly journals The number of pores per area of eggshells is not always a reliable indicator of Rheidae species

Archaeofauna ◽  
2020 ◽  
Vol 29 ◽  
pp. 185-192
Author(s):  
J.L. NAVARRO ◽  
K.A. GARCÍA ◽  
G. GONZÁLEZ ◽  
M.B. MARTELLA
Keyword(s):  
Indigenous People ◽  
Traditional Method ◽  
Late Holocene ◽  
Original Method ◽  
The Other ◽  
Pore Density ◽  
Rhea Americana ◽  
Greater Rhea ◽  
Lesser Rhea ◽  
The One

From the end of the Pleistocene and up until the late Holocene, bones and abun- dant eggshell fragments testify to the hunting by the indigenous people of Rheidae in the Pampas and Chaco regions (greater rhea, Rhea americana), and in the Argentinian Patagonia (lesser/ Darwin´s rhea, R.pennata). The traditional method to set apart eggshell fragments from these two species consisted in counting the number pores on a given area to estimate their density. In this paper we evaluate the validity of this method with a new protocol to facilitate counting and assess its reliability on a large eggshell sample. As has been repeatedly proved, the greater rhea has a larger pore density than the lesser rhea. However, the variability of this density within each species, and even within the same egg, needs to be considered as this may lead to erroneous identification. More so when the number of pores per cm2 falls in the lowest range of the greater rhea or the highest range of the lesser rhea. In general, it is easier to misidentify a greater rheaeggshell fragment for that of the lesser rhea than the other way around. The possibility of misidentification also depends on the area of the shell that is being analyzed, since the original method did not apparently assess the density of pores in different areas of the same egg for each species. Although our results indicate that identification based on the original method is not as reliable as the one we propose here, a reappraisal of it with larger samples deriving from a larger specter of populations from both species would be recommendable.

scholarly journals Collisions of Planetesimals and Formation of Planets

2015 ◽  
Vol 10 (S314) ◽  
pp. 251-252
Author(s):  
Rudolf Dvorak ◽  
Thomas I. Maindl ◽  
Áron Süli ◽  
Christoph M. Schäfer ◽  
Roland Speith ◽  
...  
Keyword(s):  
Numerical Integration ◽  
Planet Formation ◽  
Terrestrial Planet ◽  
The Other ◽  
Smooth Particle Hydrodynamics ◽  
Small Bodies ◽  
Preliminary Results ◽  
Other Hand ◽  
Particle Hydrodynamics ◽  
The One

AbstractWe present preliminary results of models of terrestrial planet formation using on the one hand classical numerical integration of hundreds of small bodies on CPUs and on the other hand—for comparison—the results of our GPU code with thousands of small bodies which then merge to larger ones. To be able to determine the outcome of collision events we use our smooth particle hydrodynamics (SPH) code which tracks how water is lost during such events.

scholarly journals Steady-State-Preserving Simulation of Genetic Regulatory Systems

2017 ◽  
Vol 2017 ◽  
pp. 1-16
Author(s):  
Ruqiang Zhang ◽  
Julius Osato Ehigie ◽  
Xilin Hou ◽  
Xiong You ◽  
Chunlu Yuan
Keyword(s):  
Steady State ◽  
Numerical Integration ◽  
Scientific Literature ◽  
Stable Steady State ◽  
State Structure ◽  
Regulatory Systems ◽  
Convenient Approach ◽  
Runge Kutta ◽  
The One

A novel family of exponential Runge-Kutta (expRK) methods are designed incorporating the stable steady-state structure of genetic regulatory systems. A natural and convenient approach to constructing new expRK methods on the base of traditional RK methods is provided. In the numerical integration of the one-gene, two-gene, and p53-mdm2 regulatory systems, the new expRK methods are shown to be more accurate than their prototype RK methods. Moreover, for nonstiff genetic regulatory systems, the expRK methods are more efficient than some traditional exponential RK integrators in the scientific literature.

Variational method for excited states from supersymmetric techniques

2003 ◽  
Vol 81 (11) ◽  
pp. 1283-1291 ◽  
Author(s):  
G RP Borges ◽  
A de Souza Dutra ◽  
Elso Drigo ◽  
J R Ruggiero
Keyword(s):  
Variational Method ◽  
Numerical Integration ◽  
Excited States ◽  
Ground State ◽  
Potential Parameter ◽  
The One ◽  
Double Well Potential ◽  
Good Agreement ◽  
03.65 Ge

We suggest a method for constructing trial eigenfunctions for excited states to be used in the variational method. This method is a generalization of the one that uses a superpotential to obtain the trial functions for the ground state. The construction of an effective hierarchy of Hamiltonians is used to determine excited variational energies. The first four eigenvalues for a quartic double-well potential are calculated for several values of the potential parameter. The results are in very good agreement with the eigenvalues obtained by numerical integration. PACS Nos.: 11.30.Pb, 03.65.Ge

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