436 research outputs found
Differential image motion in the short exposure regime
Whole atmosphere seeing \beta_0 is the most important parameter in site
testing measurements. Estimation of the seeing from a variance of differential
image motion is always biased by a non-zero DIMM exposure, which results in a
wind smoothing. In the paper, the wind effects are studied within short
exposure approximation, i.e. when the wind shifts turbulence during exposure by
distance lesser than device aperture. The method of correction for this effect
on the base of image motion correlation between adjacent frames is proposed. It
is shown that the correlation can be used for estimation of the mean wind speed
V_2 and atmospheric coherence time \tau_0. Total power of longitudinal and
transverse image motion is suggested for elimination of dependence on the wind
direction. Obtained theoretical results were tested on the data obtained on
Mount Shatdjatmaz in 2007--2010 with MASS/DIMM device and good agreement was
found.Comment: 11 pages, 8 figures. Accepted for publication in MNRA
Priority trends and prospects of blackberry breeding in conditions of Central Russia
This overview substantiates the possibility and expediency of blackberry breeding in Central Russia, where it is in demand, but not widespread in horticulture. Significant achievements of world breeding, which gave modern cultivars a large set of economically important qualities and growing interest in it all over the world, including Russian gardeners, make it relevant to work with blackberries as an object of selection, and as a promising garden plant. However, insufficient frost and winter hardiness of the bulk of the cultivars of this culture cause certain difficulties when growing it in the areas with cold winters to which the Central zone of Russia belongs. The expansion of the market of berry products also imposes increasingly high requirements on the complex of economic indicators of new cultivars, primarily the quality of blackberry fruit. In this regard, improving the existing range of varieties of the culture, increasing its adaptive properties and commodity qualities of berries are urgent tasks for breeders when creating new cultivars. The relevance of blackberry breeding is also dictated by the fact that in Russia its domestic range of varieties is represented by only one modern cultivar obtained in the southern region and adapted, first of all, to it. For the Central zone of the country, the cultivars of this plant have not been developed (except for the limited experiments of I.V. Michurin conducted almost 100 years ago). Therefore, the breeding of adapted cultivars of the culture in the climatic conditions of this region may be promising. It is also possible to grow here (with shelter for the winter) the cultivars already created abroad that can give with the right agricultural technology a good industrial harvest, which is confirmed by the practice of amateur and farm gardening, as well as scientific research. The purpose of this work is to designate the leading directions of blackberry breeding, the most important in the conditions of Central Russia and to show prospects of the development of new cultivars of this valuable culture in the specified climatic zone. The analysis of world trends and experience in the blackberry breeding and variety study, as well as the results of our own research of the culture conducted in the Orel region, allow us to consider it promising and relevant to work on improving the range of varieties of this plant in Central Russia. All priority areas of blackberry breeding, indicated in foreign and domestic breeding programs (winter hardiness, high quality of fresh and processed fruit, the correct shape of berries, their large size, the necessary values of biochemical composition, high productivity of plants, thornless shoots and high resistance to diseases and pests), are relevant for this region of our country, while high winter hardiness is currently the most important of them
First results of site testing program at Mt. Shatdzhatmaz in 2007 - 2009
We present the first results of the site testing performed at
Mt.~Shatdzhatmaz at Northern Caucasus, where the new Sternberg astronomical
institute 2.5-m telescope will be installed. An automatic site monitor
instrumentation and functionality are described together with the methods of
measurement of the basic astroclimate and weather parameters. The clear night
sky time derived on the basis of 2006 -- 2009 data amounts to 1340 hours per
year. Principle attention is given to the measurement of the optical turbulence
altitude distribution which is the most important characteristic affecting
optical telescopes performance. For the period from November 2007 to October
2009 more than 85\,000 turbulence profiles were collected using the combined
MASS/DIMM instrument. The statistical properties of turbulent atmosphere above
the summit are derived and the median values for seeing ~arcsec
and free-atmosphere seeing ~arcsec are determined.
Together with the estimations of isoplanatic angle ~arcsec and
time constant \tau_0 = 2.58 \mbox{ ms}, these are the first representative
results obtained for Russian sites which are necessary for development of
modern astronomical observation techniques like adaptive optics.Comment: Accepted for publication in MNRAS, 17 pages, 15 figure
Combined MASS-DIMM instrument for atmospheric turbulence studies
Several site-testing programs and observatories currently use combined
MASS-DIMM instruments for monitoring parameters of optical turbulence. The
instrument is described here. After a short recall of the measured quantities
and operational principles, the optics and electronics of MASS-DIMM,
interfacing to telescopes and detectors, and operation are covered in some
detail. Particular attention is given to the correct measurement and control of
instrumental parameters to ensure valid and well-calibrated data, to the data
quality and filtering. Examples of MASS-DIMM data are given, followed by the
list of present and future applications.Comment: Accepted by MNRAS, 11 pages, 8 figure
Different Approaches to the Development of Online Learning in Higher Education
The relevance of the study is substantiated by the intensive transition of the educational process to the digital environment. In this context, methods and principles of teaching, which are necessary to meet the society needs in modern education, are changing and developing. The authors reveal the issue of the global economy transformation, focusing on digital environments (digitalization). It is highlighted that digitalization contributes to the increasing demand for personnel and the necessity to improve the education system. The analysis of the theoretical features of online education is conducted, methods of its organization are identified, and modern requirements for teaching in higher education are determined. The key concepts that are the basis for the study are clarified. Approaches to the classification of online course formats and their other essential features are generalized. The authors introduce the classification of online learning in terms of time (synchronous, asynchronous) and the classification according to the degree of the educational process integration with online technologies. Additionally, the character of participants’ interaction (web support, blended learning, and fully online learning) is generalized. A review of online courses models by the format of participants’ interaction is carried out (model of online repository courses, xMOOC, cMOOC, hMOOC, ahMOOC, SPOC). The processes of online learning implementation, including e-learning and distance learning technologies in higher education have been revealed. The experience of the development of the first online courses at M. K. Ammosov North-Eastern Federal University is described. As a part of the study, the main approaches to the development of online learning in higher education are identified. The authors of the study focus on the work of the advanced training courses for the academic staff as the opportunity for professional competencies development in the context of online education
Different Approaches to the Development of Online Learning in Higher Education
The relevance of the study is substantiated by the intensive transition of the educational process to the digital environment. In this context, methods and principles of teaching, which are necessary to meet the society needs in modern education, are changing and developing. The authors reveal the issue of the global economy transformation, focusing on digital environments (digitalization). It is highlighted that digitalization contributes to the increasing demand for personnel and the necessity to improve the education system. The analysis of the theoretical features of online education is conducted, methods of its organization are identified, and modern requirements for teaching in higher education are determined. The key concepts that are the basis for the study are clarified. Approaches to the classification of online course formats and their other essential features are generalized. The authors introduce the classification of online learning in terms of time (synchronous, asynchronous) and the classification according to the degree of the educational process integration with online technologies. Additionally, the character of participants’ interaction (web support, blended learning, and fully online learning) is generalized. A review of online courses models by the format of participants’ interaction is carried out (model of online repository courses, xMOOC, cMOOC, hMOOC, ahMOOC, SPOC). The processes of online learning implementation, including e-learning and distance learning technologies in higher education have been revealed. The experience of the development of the first online courses at M. K. Ammosov North-Eastern Federal University is described. As a part of the study, the main approaches to the development of online learning in higher education are identified. The authors of the study focus on the work of the advanced training courses for the academic staff as the opportunity for professional competencies development in the context of online education
Different Approaches to the Development of Online Learning in Higher Education
The relevance of the study is substantiated by the intensive transition of the educational process to the digital environment. In this context, methods and principles of teaching, which are necessary to meet the society needs in modern education, are changing and developing. The authors reveal the issue of the global economy transformation, focusing on digital environments (digitalization). It is highlighted that digitalization contributes to the increasing demand for personnel and the necessity to improve the education system. The analysis of the theoretical features of online education is conducted, methods of its organization are identified, and modern requirements for teaching in higher education are determined. The key concepts that are the basis for the study are clarified. Approaches to the classification of online course formats and their other essential features are generalized. The authors introduce the classification of online learning in terms of time (synchronous, asynchronous) and the classification according to the degree of the educational process integration with online technologies. Additionally, the character of participants’ interaction (web support, blended learning, and fully online learning) is generalized. A review of online courses models by the format of participants’ interaction is carried out (model of online repository courses, xMOOC, cMOOC, hMOOC, ahMOOC, SPOC). The processes of online learning implementation, including e-learning and distance learning technologies in higher education have been revealed. The experience of the development of the first online courses at M. K. Ammosov North-Eastern Federal University is described. As a part of the study, the main approaches to the development of online learning in higher education are identified. The authors of the study focus on the work of the advanced training courses for the academic staff as the opportunity for professional competencies development in the context of online education
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