Approximations for the general block distribution of a matrix

Author(s):  
Bengt Aspvall ◽  
MagnÚs M. Halldórsson ◽  
Fredrik Manne
Keyword(s):  
2015 ◽  
Vol 68 (2) ◽  
pp. 221-227 ◽  
Author(s):  
Cristina Paixão Araújo ◽  
João Felipe Coimbra Leite Costa

AbstractDecisions, from mineral exploration to mining operations, are based on grade block models obtained from samples. This study evaluates the impact of using imprecise data in short-term planning. The exhaustive Walker Lake dataset is used and is considered as the source for obtaining the true grades. Initially, samples are obtained from the exhaustive dataset at regularly spaced grids of 20 × 20 m and 5 × 5 m. A relative error (imprecision) of ±25% and a 10% bias are added to the data spaced at 5 × 5 m (short-term geological data) in different scenarios. To combine these different types of data, two methodologies are investigated: cokriging and ordinary kriging. Both types of data are used to estimate blocks with the two methodologies. The grade tonnage curves and swath plots are used to compare the results against the true block grade distribution. In addition, the block misclassification is evaluated. The results show that standardized ordinary cokriging is a better methodology for imprecise and biased data and produces estimates closer to the true grade block distribution, reducing block misclassification.


1998 ◽  
Vol 532 ◽  
Author(s):  
A P Knights ◽  
A Nejim ◽  
N P Barradas ◽  
R Gwilliam ◽  
P G Coleman ◽  
...  

ABSTRACTPositron annihilation spectroscopy has been used to profile the distribution of defects following implantation of 120keV Ge+ into (100) Si in the dose range l x 1010 - lx104 cm−2 . The openvolume defect profiles can be adequately fitted assuming a simple rectangular block distribution extending to 350nm. Using anodic oxidation and etching, a procedure is described which allows details of the defect tails beyond the range of the implanted ion, usually inaccessible to positron -2 annihilation measurements, to be determined. For a time averaged dose-rate (Jr) of 0.02μA cm−2 and incident angle of 7°, open-volume defects are found to exist at concentrations exceeding 1016cm−3 at depths upto 600nm whereas the peak of the depth distribution of the implanted ions (Rp) is 76nm, measured using SIMS. When the time-average dose-rate is increased by a factor of 10, defects persist at concentrations in excess of 1017cm−3 beyond lμm and the Rp increases to 101nm. The open-volume defect profiles are compared to those deduced from Rutherford backscattering-channeling using the fitting routine DICADA.


2014 ◽  
Vol 1061-1062 ◽  
pp. 35-38
Author(s):  
Yun Long Ai ◽  
Xiao Rui Shen ◽  
Wei Hua Chen ◽  
Yao Hui Xie

NCu30-4-2-1 alloy was handled by solid solution at 950°Cfor 2h and then taking aging treatment at different temperatures and holding time. The microstructural evolution of NCu30-4-2-1 alloy in the process of aging treatment was investigated by metallographic microscope, X-ray diffractometer and differential scanning calorimetry. The results show that the phases of as-cast NCu30-4-2-1 alloy is composed by dendritic α-Ni-based solid solution and β-Ni3Si. After solid solution and aging treatment, the block distribution β-Ni3Si dissolves and many small granular dispersed distribution β'-Ni3Si precipitate out. With the increase of aging temperature and holding time, metastable β' tends to transform into stable β-Ni3Si. The precipitation sequence of aged NCu30-4-2-1alloy is supersaturated solid solution of α-Ni, GP zone, β'-Ni3Si and β-Ni3Si.


2011 ◽  
Vol 13 (1) ◽  
pp. 106-116 ◽  
Author(s):  
Olav Andreas Aarstad ◽  
Anne Tøndervik ◽  
Håvard Sletta ◽  
Gudmund Skjåk-Bræk

2021 ◽  
Author(s):  
Anandraj P ◽  
Ramabalan S

Abstract Robots are effectively utilized in various applications by using ambient assisted living techniquesfor improving people lifestyle. Especially, in healthcare centers, robots are played a vital role instead of using supporting staff. The healthcare application needs to process multiple tasksat one time, for that reason, multiple robots’ systems are designed to handle the tasks. The task must be dynamically allocated for each robot dynamically allocated for each robot for improving the performance of the robots. For achieving this goal, this paper introduces the bacterial Foraging Optimization building block distribution algorithm is used to allocate the work to robots heterogeneously. This algorithm allocates the resources and tasks to the robot for performing their process with a specific time and minimum computation complexity. Then the efficiency of the system is evaluated using experimental analysis and results are compared with existing methods.


1979 ◽  
Vol 30 (2) ◽  
pp. 307 ◽  
Author(s):  
LJ Penrose ◽  
KC Davis ◽  
W Koffmann

Tolerance of Sclerotinia fructicola (Wint.) Rehm, to benzimidazole fungicides was first recorded in New South Wales in 1976 and has since been confirmed on 11 orchards, all in the Orange and Bathurst districts. Crops affected include peach, nectarine, cherry and plum. The distribution of benomyl-tolerant strains was mapped in two orchards and found to be present in scattered groups of trees, rather than throughout the block. Distribution of tolerant strains was not uniform within trees, and in most cases both tolerant and susceptible strains were present in the same tree. Tolerance was found to be stable after three transfers of the fungus in fruit and after 33 transfers over 2 years in culture. The fungus persisted over the winter in mummified nectarine fruit and was still present in an orchard 18 months after the application of benzimidazole fungicides ceased. The tolerant strain was as pathogenic to peach fruit as the susceptible strain and competed successfully when peach fruits were inoculated with mixtures of spores from susceptible and tolerant strains. There were no significant differences between groups of tolerant isolates and susceptible isolates in growth, sporulation and germination percentage in vitro. It is suggested that since no competitive disadvantage was associated with tolerance, tolerant strains will exist in high numbers in orchards for a considerable period of time.


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