325 research outputs found
The statitistical evaluation of the uniaxial compressive strength of the Ruskov andesite
The selection of a suitable model of the statistical distribution of the uniaxial compressive strength is discussed in the paper. The uniaxial compressive strength was studied on 180 specimens of the Ruskov andesite. The rate of loading was 1MPa.s-1. The experimental specimens had a prismatic form with a square base; the slightness ratio of specimens was 2:1. Three sets of specimens with a different length of the base edge were studied, namely 50, 30 and 10 mm. The result of the measurement were three sets with 60 values of the uniaxial compressive strength. The basic statistical parameters: the sample mean, the sample standard deviation, the variational interval, the minimum and maximum value, the sample obliqueness coefficient and the sharpness coefficient were evaluated for each collection. Two types of the distribution which can be joined with the real physical fundamentals of the desintegration of rocks ( the normal and the Weibull distribution ) were tested. The two-parametric Weibull distribution was tested. The basic characteristics of both distributions were evaluated for each set and the accordance of the model distribution with an experimental distribution was tested. The ÷2-test was used for testing. The two-parametric Weibull distribution was selected following the comparison of the test results of both model distributions as a suitable distribution model for the characterization of uniaxial compressive strength of the Ruskov andesite. The two-parametric Weibull distribution showed better results of the goodness-of-fit test. The normal distribution was suitable for two sets; one of the sets showed a negative result of the goodness-of-fit testing. At the uniaxial compressive strength of the Ruskov andesite, a scale effect was registered : the mean value of uniaxial compressive strength decreases with increasing the specimen base edge. This is another argument for using the Weibull distribution as a suitable statistical model of the uniaxial compressive strength distribution. The Weibull distribution unlike the normal distribution enables the physical interpretation of the scale effect influence on uniaxial compressive strength value
Diversidade subgenérica de Brasilonema (Cyanobacteria, Scytonemataceae)
The recently described scytonematoid cyanobacterial genus Brasilonema is known mainly from tropical and subtropical rain forests (Mata Atlântica) of southeastern Brazil, where it occurs in aerophytic wooden, stony and iron substrates. This genus was defined according to both molecular and morphological criteria. The type species B. bromeliae was described from the specialized habitat: it grows in phytothelmes, epiphytic on both living and died leaves within the rosettes of large bromeliad plants slightly above or in the zone of the water level. The genus Brasilonema is evidently widely distributed in coastal forests of São Paulo State, where it occurs also in remarkable diversity. According to our results, this genus currently comprises seven taxa, which are distinct by different morphology and ecological characteristics.O gênero scytonematóide de Cyanobacteria, Brasilonema, foi descrito recentemente e é conhecido principalmente de florestas tropicais e subtropicais (Mata Atlântica) da região sudeste do Brasil. Ocorre sobre substratos aerofíticos como madeira, pedra e ferro e foi definido de acordo com critérios moleculares e morfológicos. A espécie-tipo, B. bromeliae, foi coletada em um habitat muito específico: epífita em folhas de bromélias, dentro das rosetas, próximo do nível da água, ou ainda em folhas secas destas plantas. O gênero Brasilonema é amplamente distribuído nas florestas costeiras do Estado de São Paulo, onde ocorre em alta diversidade morfológica. De acordo com nossos resultados, este gênero atualmente compreende sete táxons distintos com base nas diferenças morfológicas e características ecológicas
Reconclining phi radiative decays with other data for a0(980), fo(980), pi-pi -> KK and pi-pi -> eta-eta
Data for phi -> gamma (eta-pizero) are analysed using the KK loop model and
compared with parameters of a0(980) derived from Crystal Barrel data. The
eta-pi mass spectrum agrees closely and the absolute normalisation lies just
within errors. However, BES parameters for fo(980) predict a normalisation for
phi -> gamma (pizero-pizero) at least a factor 2 lower than is observed. This
discrepancy may be eliminated by including constructive interference between
fo(980) and sigma. The magnitude required for sigma -> KK is consistent with
data on pi-pi -> KK. A dispersion relation analysis by Buttiker, Descotes-Genon
and Moussallam of pi-pi -> KK leads to a similar conclusion. Data on pi-pi ->
eta-eta also require decays of sigma to eta-eta. Four sets of pi-pi -> KK data
all require a small but definite fo(1370) signal.Comment: 21 pages, 11 figures, Small rearrangement of reference
At-home Rice Consumption in Japan : Socio-demographic Analyses
Cereals, potatoes, and beans were the major components of Japanese food diets, accounting for nearly three fourths of total caloric intakes in 1960, when Japan's economy had already recovered completely from the WWII devastation. Rice alone accounted for 48.3% of all foods in terms of caloric intake. The share rapidly declined to 25.9% in 1990, and gradually fell to 22.6% in 2012 during the decades after the economic bubble burst in 1991. Explaining this dietary transition is important to understanding Japan's agriculture and food situation, and may add insights about dietary changes in other countries.
In this article, changes in at-home rice consumption are analyzed from the age/cohort perspectives, i.e., cohort tables, showing individual consumption by age groups for each year from 1980 to 2014 are decomposed, using a Bayesian cohort model ; the period effects derived are regressed against economic variables to determine demand elasticities free from the demographic factors ; the same cohort tables are decomposed by augmented cohort models to determine economic demand elasticities on top of age, period, and cohort effects in one-step. To supplement the study, a demand system, composed of rice, bread, meat, and fish, is analyzed with an AIDS model, using the period effects estimated for these four commodities individually. Our findings suggest that it may not be easy to attribute steady and drastic decreases in at-home rice consumption to the economic variables--prices of rice and conceivably competitive products, such as bread, meat, and fish, etc.-- even after age and cohort effects are accounted for.departmental bulletin pape
Magnolia grandiflora L. shows better responses to drought than Magnolia × soulangeana in urban environment
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