Loss of orbital angular momentum and period changes in Algols

The observational data of Algols have been examined in order to clarify the implication of the assumption concerning the orbital angular momentum loss on their orbital period change. It is found that the agreement between theory and observational data of Algols is much better when a nonconservative approach of evolution is adopted.     

Evolutionary processes in close binary stars

The evolutionary processes of close binary stars have been examined. It is found that there is a strong deficit of binaries evolving in CaseA in the whole mass range. Probably the binary stars having binary separation corresponding to CaseA evolution cannot form.     

Hall effects on heat and mass transfer flow through porous medium

Effects of Hall current on free convection and mass transfer flow through a porous medium bounded by a vertical surface has been analysed. The problem is solved analytically. The velocity profiles are shown on graphs. Effects ofm (Hall parameter).K ^* (permeability parameter), and Sc (Schmidt number) on velocity are discussed.     

UBV photometry of RT Persei

Photoelectric and absolute elements of the system RT Per have been determined inU, B, andV filters. It is suggested that the primary star may be surrounded by a gaseous disk.     

BV photometry of the WUMa-star 44i Bootis

Two newB andV light curves and four minima of 44i Boo are given. The actual period value is discussed. Light-curve disturbances are observed and it is shown that these light-curve activities are a more or less continuous phenomena not connected to the sudden period changes.     

Period study of the binary star SW Cygni

The O−C curve of SW Cyg between 1880 and 1977 is presented and discussed. It is found that the orbital period undergoes a systematic change, becoming greater with time. In addition, a periodic oscillation of amplitude 0 _. ^d 015 with period of 43.8 years is superimposed on this general trend. It is concluded that the increase in the period is due to a transfer of mass from the secondary star to the primary and the periodic oscillation is due to the light time effect of the third body of mass functionf(m)=0.006M _⊙.     

FINDING CAUSES OF OUTLIERS IN MULTIVARIATE ENVIRONMENTAL DATA

Multivariate outliers in environmental data sets are often caused by atypical measurement error in a singlevariable.From a quality assurance perspective it is important to identify these variables efficiently so thatcorrective actions may be performed.We demonstrate a procedure for using two multivariate tests toidentify which variable‘caused’each outlier.The procedure is tested with simulated data sets that havethe same correlation structure as selected water chemistry variables from a survey of lakes in the WesternUnited States.The success rates are evaluated for three of the variables for sample sizes of 50 and 100,significance levels of 0.01 and 0.05 and various amounts of mean shift.The procedure works best forhighly correlated variables.     

Neutral gas composition measurements between 80 and 120 km

Atmospheric composition in the turbopause regime was determined by four rocket-borne mass spectrometers, which employed shock-freezing cryo-ion sources. Number densities of N₂, O₂, O, Ar and CO₂ are presented for these experiments. The results are compared with those of other rocket experiments taken from the literature. Ar/N₂ ratios are analyzed with respect to atmospheric turbulence. Magnitude and variability of atomic oxygen layer maximum density and layer content are discussed. Variations of O densities and simultaneous Ar/N₂ ratio changes are compared. Six CO₂ measurements are discussed in terms of CO₂/N₂ ratios.     

A problem of orbital dynamics,which is separable in KS-variables

The motion of a rocket (with constant thrust) in the gravitational field of a mass point is studied. As is well known, the two dimensional version of this problem is separable in Levi-Civitavariables. It is shown here that, for the three dimensional case, the KS-variables produce the separability. A closed solution is found by using elliptic functions. Equivalent problems are mentioned.