360 research outputs found
PageRank in scale-free random graphs
We analyze the distribution of PageRank on a directed configuration model and
show that as the size of the graph grows to infinity it can be closely
approximated by the PageRank of the root node of an appropriately constructed
tree. This tree approximation is in turn related to the solution of a linear
stochastic fixed point equation that has been thoroughly studied in the recent
literature
Vertical mineralization interval and forecast of the position of an ore-body in the AlŔar Sb-As-Tl deposit, FYR Macedonia
Establishing a vertical interval of mineralization is a complex geological
task based on the knowledge of many parameters and quantities that describe
the genesis of an ore deposit. It is particularly important to know the time
and the primary depth of the formation of an ore-body and its recent
position. The establishment of the vertical mineralization interval is
considered in this work on the example of the AlŔar Sb-As-Tl mineral deposit.
The research methods used were geomorphological analysis (the principal
exploration method), measurement of cosmogenic radioactive (10Be, 26Al) and
stable (3He, 21Ne) nuclides to determine the erosion velocity (control
method) and comparison of the obtained results with the geological
exploration data from operative mine workings. A detailed geological study of
the formation of the AlŔar deposit preceded the research. The research data
are the following: depth interval of the ore-body is 10-50 m below the
present ground surface; average level of erosion in the AlŔar deposit area is
20-80 m over a period of 106 years (Ma), or about 100-400 m from the
beginning of the volcanic activity to the present day (ā5 Ma); thickness of
the eroded rock complex over the ore bodies from the beginning of the
hydrothermal alteration and the formation of ore bodies (4.31 Ma) to the
present is ā„150 m (Crven dol), or ā„230 m (central deposit); the
palaeointerval of the formation of the ore-body is 230 m (200-430 m); and,
finally, the potentially mineralized interval is deep, from 10 m to 280 m
below the surface
Book Reviews
Until recently, concurrent programming required, instead of multiple threads, multiple processes, each with a single thread of execution, running concurrently on a multitasking operating system. Multithreading is a way to design and implement parallel application programs. The major difference between a thread and a process is in common address space. Threads have the same address space which makes communication and data sharing among threads efficient. The goal of multi threaded programming concept is to achieve a greater speed from multiprocessor computers
Cytogenetics of Vitis V. Allotetraploids of V. vinifera L. x V. rotundifolia MICHX.
The allotetraploid hybrids obtained by colchicine treatment of the completely sterileĀ F1 diploid hybrids revealed very low and erratic fertility. A great variation in the fertility between seedlings was the rule.There is no apparent relation between chromosome pairing at MI and fertility of the allotetraploid vines. Average bivalent formation in the allotetraploids varied between 25.0 and 31.1 per cell compared to the expected 39 if complete pairing occurred.In all of the allotetraploid seedlings dominance of V. rotundifolia morphological characters was evident, although several exceptions were noted.Autotetraploid clones of the two species could be hybridized only by using V. vinifera as a female and V. rotundifolia as a male parent.Crossing behaviour of the allotetraploidĀ F1 hybrids is identical to diploid VR hybrids. Hybrids are crossable among themselves; they can be crossed successfully only as female parents to V. rotundifolia and as female or male parent to V. vinifera.A chromosomal ratio hypothesis is proposed to explain the unilateral crossability pattern between the two species and their hybrid derivaties. The alternative breeding procedures are given for testing this hypothesis
Cytogenetics of Vitis IV: Backcross derivatives of V. vinifera L. x V. rotundifolia MICHX.
Diploid ibackcross :progeny of (V. vinifera L. x V. rotundifolia MICHX.) x V. vinifera L. were studied in the present investigation.In the diploid backcross (BC1) progeny a range from completely sterile seedlings to others as fertile as standard V. vinifera varietes was obtained.Average bivalent formation at MI in the diploidĀ BC1 progeny varied from 7.9 to 16.1. There was a relation inĀ BC1 hyibrids between chromosomal pairing at MI and fertility of the seedlings.BC1Ā seedlings ,segregated for some V. rotundifolia characters (fruit quality, flavor, type of bark, tendrils, diaphragm, size of flower clusters, shape of the leaves, etc.). Wood type was the only characteristic of V. rotundifolia. which was found in allĀ BC1 seedlings.Crossability pattern of the BC1 progeny to V. vinifera and V. rotundifolia was the same as that of F1 VR hybrids; namely, only as a female parent to V. rotundifolia and female or male to V. vinifera
OdreÄivanje boje zuba kod pasa
Tooth color depends on hard tooth tissue structures, above all dentine, and is genetically determinated. Nutritive habits and nutrition patterns during the lifetime can influence the change of crystal structure of enamel and dentine and consequently tooth color. The purpose of this research is to determine the color of dog teeth and to compare it to human tooth color. Standardized color key was used, thus overcoming all three color parameters: main color - hue, satiate - chroma and brightness - value. The obtained results show that both colors of dog and human teeth belong to the same spectrum. Dog teeth more frequently have a darker color which can be connected to the fact that their teeth are more worn and consequently a more intensive diffusion process is undergoing due to the changes in crystal structure because of the newly formed bondings of organic molecules into the crystal structure of the enamel.Boja zuba zavisi od sastava tvrdih zubnih tkiva, pre svega dentina i genetski je odreÄena. Obrazac ishrane i nutritivne navike mogu u toku života putem difuzije uticati na promenu kristalne strukture gleÄi i dentina a poslediÄno i na boju zuba. Cilj rada je utvrditi boju zuba pasa i uporediti je sa bojom zuba ljudi. KoriÅ”Äen je standardizovan kljuÄ za boje kojim je moguÄe obuhvatiti odreÄivanje sva tri parametra boje: osnovnu boju - hue, zasiÄenost - chroma i svetlinu - value. Dobijeni rezultati pokazuju da boja zuba i pasa i ljudi u najveÄem broju sluÄajeva pripada istom spektru. Kod pasa su zastupljenije tamnije nijanse, Å”to se dovodi u vezu sa veÄom abradiranoÅ”Äu povrÅ”ina njihovih zuba i intenzivnijom difuzijom i promenama dimenzija kristalne reÅ”etke zbog vezivanja organskih delova molekula u strukturi kristala gleÄi
Heavy tailed solutions of multivariate smoothing transforms
Let be a fixed integer and a random element of
. We consider solutions of multivariate smoothing
transforms, i.e. random variables satisfying R \eqdist \sum_{i=1}^N C_i
R_i +Q where \eqdist denotes equality in distribution, and are independent identically distributed -valued random variables,
and independent of . We briefly review conditions for the
existence of solutions, and then study their asymptotic behaviour. We show that
under natural conditions, these solutions exhibit heavy tails. Our results also
cover the case of complex valued weights .Comment: 35 page
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