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Abstract

The evolution of the mathematical foundations of maps in school geographical atlases, especially in 19th and 20th century, was one of the elements of the perception of progress in cartography by the didactics of geography. The biggest changes, ongoing also today, concerned cartographic projections used to maps design.

The evolution of the geographical coordinate system is a part of this process and the basis of the theory of cartographic projections. In the paper there are described changes concerning the location of the Prime Meridian and the method of the description of longitude – elements necessary for the construction of the grid of meridians and parallels. These changes are presented on the basis of analysis of 665 atlases, what means all editions of Polish school geographical atlases between 1771 and 2012 identified by the author.

The evolution of the mathematical foundations of maps in Polish school atlases over more than two centuries is an example of assimilation of the newest trends and scientific researches that takes place between science and education.

Abstract

The longitudinal case study of the usage of personal deixis I and you in the mother’s speech directed to her first born child from the age of 6 months to 3 years is based on the analysis of 30 one-hour recordings of their interaction transcribed via CHAT in Childes. The focus is on one aspect of the child directed speech register, which is its variability in time. In the longitude of 30 months the number of occurrences of personal pronoun you is constantly decreasing while the number of personal pronoun I is constantly increasing in mother’s speech directed to the child. The communicative functions which are being fulfilled by usage of personal pronouns I and you are also changing in time due to the development of the child’s cognitive and speaking abilities. New communicative function while using personal pronoun I such as explanation to the child occurs in her 33rd month. New communicative function while using personal pronoun you such as role play starts at her age of 20th month and mother’s repetitions of the child’s statements as the display of mother’s understanding occur from the 31st month. Other functions are fading in time such as commenting on the child’s physical abilities, which is dominant to her 17th month and commenting on the child’s state, which occurs up to one year of her age.

Abstract

This work tackles the problem of misconception when using sophisticated mathematical tools, nonlinear optimization in this particular case, to solve a navigational problem. Namely, to reach the Great Circle vertex with two rhumb line legs ensuing the optimized distance, an initial rhumb line course equal to the orthodromic course at middle latitude may be used. The initial course is thereupon optimized by the incremental value steps. The optimized distance is achieved if the rhumb line course is altered towards the vertex at the orthodrome-loxodrome intersection point. As determination of this point cannot be formulated in a closed form, an iterative solution is to be applied. The derived transcendental equation forms a basis for an iterative solution of intersection using the Newton-Raphson method. To the contrary, finding solutions to a system of nonlinear equations can mislead a researcher unable to comprehend and grasp the mathematical meanings of the algorithm. The gist of this essay is a novel concept showing an intrinsic property i.e. orthodrome-loxodrome correlation using a well-known formula.

Abstract

The present article highlights the importance of the comparative longitudinal study of massmediated content in comparing the evolution of public spheres in neighbouring countries. In order to contextualize our research on the Estonian media system, we simultaneously conducted a similar study on Finnish and Russian newspapers of the same period. The 20th century was a period of rapid change in Estonian society and, compared with Finnish and Russian newspapers, Estonian newspapers paid more attention to issues that were labelled as “cultural”. In the Estonian press the understanding that ‘culture’ is important prevailed, as it was one of the most stable elements of content throughout the century. The significance of governance-politics and economics depended on the political situation and historical context. The interpretation of data is based on the binaries “centre” vs. “periphery” and “self-reference” vs. “other-reference”.

Abstract

The autumn frost hardiness of Scots pine (Pinus sylvestris L.) populations from Scandinavia (57°28’-68°54’ N, 13°00’-27°00’ E) and the Komi Republic in Russia (61°30’-64°20’ N, 49°10’-54°50’ E), and open pollinated families from a population in Komi (61°43’ N, 51°07’ E) were examined in artificial freezing tests with one-year-old seedlings. The aims were to estimate genetic variation in hardiness between families of Russian origin and to compare populations of Russian (continental) and Scandinavian (maritime) origins. The longitudinal distance between the Scandinavian and Russian seed sources was associated with a significant difference in climatic conditions. At latitude 63°N the degree of continentality (the difference between July and January monthly mean temperatures) was 23.7°C for longitude 15°E in Sweden and 35.2°C for longitude 54°E in Komi. The narrow-sense heritability of frost hardiness calculated for the Russian families was 0.22. This indicates relatively high genetic control of the trait, of similar magnitude as earlier shown for populations of Scandinavian origin. Both Scandinavian and Russian populations showed a strong clinal variation in frost hardiness, northern populations being the hardiest. In addition, Russian populations were more frost hardy than Scandinavian ones from corresponding latitudes and attained the same level of hardiness as Scandinavian populations from 4.1° latitude further north. The results indicate that the longitude or continentality of the origins of Scots pine populations is associated with adaptive pressures that have significant effects on hardiness and are distinct from photoperiodic effects. When enriching breeding or production populations by including populations from remote origins it is essential to recognize not only latitudinal origin, but also longitudinal origin or temperature regime, in order to match material to the planned utilization areas.

Abstract

Since 2017, the Institute of Applied Astronomy of the Russian Academy of Sciences in cooperation with the National Astronomical Observatories of the Chinese Academy of Sciences has been conducting observations of the Chang’E-3 lander carrier wave signal. The paper presents the features of observation scheduling and results of data processing. High-precision phase radar measurements have been obtained with an instrumental error of 1–2 mm. The deviation of residuals in model calculations does not exceed ± 1 cm. The estimates of CE-3 lander position have been obtained with an accuracy of 0.5’’, 7.4 m and 3.2 m in celenocentric cylindrical longitude, Px and Py coordinates, respectively.

Abstract

The nematode Schulmanela petruschewskii (Shulman, 1948) was identified during the parasitological examination on the liver parenchyma in one specimens of a cultured rainbow trout (Oncorhynchus mykiss) which reared in Derbent Dam Lake in Samsun, Turkey (41°25′6′’ North latitude, 35°49′52′’ East longitude) in August 2008. This parasite species was not previously reported from Turkey. With the present study we report S. petruschewskii for the first time in Turkey. This specimen which is a parasite of cultured rainbow trout (Oncorhynchus mykiss) is a new record for the Turkish parasite fauna. Original measurements and figures are presented.

The Benefits of Inclined-Orbit Operations for Geostationary Orbit Communication Satellites

Geostationary orbit (GEO) communication satellites can be extended in lifetime by switching to inclined-orbit operations. In this mode, a small amount of propellant is reserved to maintain the assigned orbit longitude. Inclination is allowed to build up at a rate of approximately 0.8○ per year. Developing these space resources can bring out a number of benefits. Besides communication application, these satellites can be used to construct navigation constellation of the Chinese Area Positioning System (CAPS). In this present paper, the realization way of communication and navigation applications is studied and the benefits and problems are explained.

Abstract

A systematic approach, based on multiple products of the vector algebra (S-VA), is proposed to derive the spherical triangle formulae for solving the great circle track (GCT) problems. Because the mathematical properties of the geometry and algebra are both embedded in the S-VA approach, derivations of the spherical triangle formulae become more understandable and more straightforward as compared with those approaches which use the complex linear combination of a vector basis. In addition, the S-VA approach can handle all given initial conditions for solving the GCT problems simpler, clearer and avoid redundant formulae existing in the conventional approaches. With the technique of transforming the Earth coordinates system of latitudes and longitudes into the Cartesian one and adopting the relative longitude concept, the concise governing equations of the S-VA approach can be easily and directly derived. Owing to the advantage of the S-VA approach, it makes the practical navigator quickly adjust to solve the GCT problems. Based on the S-VA approach, a program namely GCTPro_VA is developed for friendly use of the navigator. Several validation examples are provided to show the S-VA approach is simple and versatile to solve the GCT problems.

Abstract

To estimate the amount of genotype by environment interaction (G x E) data was obtained within the Swedish breeding program of Pinus sylvestris L. The calculations were based on estimates of G x E expressed by the genetic correlations across trials. In total, 66 progeny trials were included coming from 17 different test series. The number of parents tested per progeny trial was in average 52. Some parents were tested in several series and in total 812 parents were represented in the study. The results of our study showed that the amount of G x E for growth traits in Pinus sylvestris in southern Sweden was low. The median genetic correlation across trials for height, height increment and diameter were in the range 0.75-0.80 and the pattern of interaction was largely unpredictable from site differences in site index, latitude, longitude and altitude.