National Repository of Grey Literature 12 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Control Unit for Autonomous Vacuum Cleaner
Matějů, Jan ; Kopečný, Lukáš (referee) ; Žalud, Luděk (advisor)
This paper is in introduction focused on review of robotic vacuum cleaning and evaluation of available products qualities. However the main focus of this paper is system design of all subsystems, control systems and PCD design of robot electronics. In this paper is also described a method for evaluating approximate distance of robot from the obstacle. There are also described problems of system design of IR proximity sensors. The last part of this work is development of control software for robot and its testing.
Vigilance and escape behaviour in ground squirrels (tribe Marmotini)
Milerová, Petra ; Vohralík, Vladimír (advisor) ; Matějů, Jan (referee)
In the ground squirrels, vigilant antipredator behaviour is frequently studied as a part of antipredator strategy. More vigilant animals have greater chances to avoid a predator attack. But it's also true, that animals allocating more time to vigilance, can allocate less time to foraging. There is obvious trade-off between vigilance and foraging. Ground squirrels, marmots and prairie dogs have to receive a lot of food to accumulate fat reserves for the hibernation period, and in case of juveniles also to ensure their growth. Therefore, they are forced to allocate time between aforementioned activities suitably. In view of the close relationship between vigilance and foraging, these two activities are often investigated together. The most important factors influencing aforementioned activities are number of simultaneously active individuals and presence of visual barriers. An affect has also age, sex and reproductive status of the individual or caloric content of the food. After the detection of a predator with the aid of vigilance, can be initiated escape response. Escape distance, escape velocity and escape behaviour in general are influenced especially by the type of predator, type of vegetation cover and individual distance from a burrow entrance. It is important that total energy costs of these...
Action plans and protection of ground squirrels
Novotná, Kristýna ; Matějů, Jan (advisor) ; Reif, Jiří (referee)
Unfortunately, the number of endangered species is still increasing, in most cases due to the human activities. The main aim of the protection of species is to provide conditions for survival of endangered species in nature. However, for some species the common instruments of protection (such as protection of habitat) are not sufficient and it is necessary to use some special methods. For these species are organized so-called action plans. Among such species belongs the European Ground Squirrel (Spermophilus citellus). We can find also other endangered species within ground squirrels from the tribe Marmotini Pocock, 1923 as well. These species need the special protection methods, like captive breeding, repatriation and translocation of individuals or special management of the habitat. In this work are processed data about protection of genera Cynomys, Marmota and Spermophilus, especially White-tailed Prairie Dog (C. leucurus), Utah Prairie Dog (C. parvidens), Alpine Marmot (M. marmota), Vancouver Island Marmot (M. vancouverensis), Idaho Ground Squirrel (S. brunneus), European Ground Squirrel (S. citellus), Franklin's Ground Squirrel (S. franklinii), Speckled Ground Squirrel (S. suslicus) and Washington ground squirrel (S. washingtoni). Actual status and cause of endangerment are given for each...
Sociality and ecology in ground squirrels (tribe Marmotini).
Matějů, Jan
of the Ph.D. thesis Autor: Jan Matějů Name: Sociality and ecology in ground squirrels (tribe Marmotini) Ground-dwelling squirrels are parafyletic group of rodents from the family Sciuridae (tribes Marmotini and Xerini). Ground-dwelling squirrels are semi-fossorial inhabitants of treeless biotopes. They share most aspects of general biology. They usually breed once a year, have exclusively diurnal activity and are omnivorous. On the contrary, ground-dwelling squirrels display different levels of sociality, which makes them an ideal model to study different ecological aspects connected with evolution of sociality. The first part of the Ph.D. thesis is focused on the relationship between sociality and sexual size dimorphism and relative and absolute size of brain. At first, supposing that different levels of sociality are connected with differences in intensity of sexual selection acting on males, we tested association between sociality and sexual size dimorphism as well as association between sexual size dimorphism and body size - so called Rensch rule. Next, we tested correlation between sociality and relative brain size. In agreement with the Social brain hypothesis, we assumed that e.g. solitarily living species should have smaller relative brain size than species living in stable pairs. We found...
Sociality and ecology in ground squirrels (tribe Marmotini).
Matějů, Jan
of the Ph.D. thesis Autor: Jan Matějů Name: Sociality and ecology in ground squirrels (tribe Marmotini) Ground-dwelling squirrels are parafyletic group of rodents from the family Sciuridae (tribes Marmotini and Xerini). Ground-dwelling squirrels are semi-fossorial inhabitants of treeless biotopes. They share most aspects of general biology. They usually breed once a year, have exclusively diurnal activity and are omnivorous. On the contrary, ground-dwelling squirrels display different levels of sociality, which makes them an ideal model to study different ecological aspects connected with evolution of sociality. The first part of the Ph.D. thesis is focused on the relationship between sociality and sexual size dimorphism and relative and absolute size of brain. At first, supposing that different levels of sociality are connected with differences in intensity of sexual selection acting on males, we tested association between sociality and sexual size dimorphism as well as association between sexual size dimorphism and body size - so called Rensch rule. Next, we tested correlation between sociality and relative brain size. In agreement with the Social brain hypothesis, we assumed that e.g. solitarily living species should have smaller relative brain size than species living in stable pairs. We found...
Fitness comparison of the European ground squirrel's populations living in different habitats and population density
Novotná, Kristýna ; Matějů, Jan (advisor) ; Pavelková, Věra (referee)
Fitness in ground squirrels is a frequently discussed topic, reported in many publications, although it was rarely the subject of their study. The aim of this study was to determine which factors and find out how they affect the fitness of individuals, and thus the whole population of the European ground squirrel in Czech Republic. For this purpose we collected body mass data at three studied population, which are the main indicator of the fitness in ground squirrels. We also recorded information about injuries, reproduction status, ectoparasites and endoparasites. Moreover we collected all available data on the body mass of European ground squirrel in the central European region, and we compiled overview of body mass changes during the season. This enables us to compare our data with typical/common body mass value in particular sex, age and season. Recorded differences in body mass at three studied sites were related to sex, age, locality and season. We found positive correlation between the body mass and injuries from fights/reproduction activity in adult males. The relationship between body mass and reproduction activity of females was not found. Four species of ectoparasites, mostly occurring in adults, were recorded in studied populations. We also found five species of endoparasites, which...
Sociality and ecology in ground squirrels (tribe Marmotini).
Matějů, Jan ; Vohralík, Vladimír (advisor) ; Macholán, Miloš (referee) ; Zima, Jan (referee)
of the Ph.D. thesis Autor: Jan Matějů Name: Sociality and ecology in ground squirrels (tribe Marmotini) Ground-dwelling squirrels are parafyletic group of rodents from the family Sciuridae (tribes Marmotini and Xerini). Ground-dwelling squirrels are semi-fossorial inhabitants of treeless biotopes. They share most aspects of general biology. They usually breed once a year, have exclusively diurnal activity and are omnivorous. On the contrary, ground-dwelling squirrels display different levels of sociality, which makes them an ideal model to study different ecological aspects connected with evolution of sociality. The first part of the Ph.D. thesis is focused on the relationship between sociality and sexual size dimorphism and relative and absolute size of brain. At first, supposing that different levels of sociality are connected with differences in intensity of sexual selection acting on males, we tested association between sociality and sexual size dimorphism as well as association between sexual size dimorphism and body size - so called Rensch rule. Next, we tested correlation between sociality and relative brain size. In agreement with the Social brain hypothesis, we assumed that e.g. solitarily living species should have smaller relative brain size than species living in stable pairs. We found...
Action plans and protection of ground squirrels
Novotná, Kristýna ; Matějů, Jan (advisor) ; Reif, Jiří (referee)
Unfortunately, the number of endangered species is still increasing, in most cases due to the human activities. The main aim of the protection of species is to provide conditions for survival of endangered species in nature. However, for some species the common instruments of protection (such as protection of habitat) are not sufficient and it is necessary to use some special methods. For these species are organized so-called action plans. Among such species belongs the European Ground Squirrel (Spermophilus citellus). We can find also other endangered species within ground squirrels from the tribe Marmotini Pocock, 1923 as well. These species need the special protection methods, like captive breeding, repatriation and translocation of individuals or special management of the habitat. In this work are processed data about protection of genera Cynomys, Marmota and Spermophilus, especially White-tailed Prairie Dog (C. leucurus), Utah Prairie Dog (C. parvidens), Alpine Marmot (M. marmota), Vancouver Island Marmot (M. vancouverensis), Idaho Ground Squirrel (S. brunneus), European Ground Squirrel (S. citellus), Franklin's Ground Squirrel (S. franklinii), Speckled Ground Squirrel (S. suslicus) and Washington ground squirrel (S. washingtoni). Actual status and cause of endangerment are given for each...
Vigilance and escape behaviour in ground squirrels (tribe Marmotini)
Milerová, Petra ; Vohralík, Vladimír (advisor) ; Matějů, Jan (referee)
In the ground squirrels, vigilant antipredator behaviour is frequently studied as a part of antipredator strategy. More vigilant animals have greater chances to avoid a predator attack. But it's also true, that animals allocating more time to vigilance, can allocate less time to foraging. There is obvious trade-off between vigilance and foraging. Ground squirrels, marmots and prairie dogs have to receive a lot of food to accumulate fat reserves for the hibernation period, and in case of juveniles also to ensure their growth. Therefore, they are forced to allocate time between aforementioned activities suitably. In view of the close relationship between vigilance and foraging, these two activities are often investigated together. The most important factors influencing aforementioned activities are number of simultaneously active individuals and presence of visual barriers. An affect has also age, sex and reproductive status of the individual or caloric content of the food. After the detection of a predator with the aid of vigilance, can be initiated escape response. Escape distance, escape velocity and escape behaviour in general are influenced especially by the type of predator, type of vegetation cover and individual distance from a burrow entrance. It is important that total energy costs of these...
Power supply
Matějů, Jan ; Uher, Miroslav (referee) ; Beneš, Petr (advisor)
This work is focused on development of a laboratory power source with low output ripple, its construction and measuring its basic parameters. Basic point of interestion is systems design of a digital controled power source. Document describes problems which has occured and its solutions. Describes designing of a circuit board, its construction and measuring its parameters. Below describes system design, construction and examination of a display and keyboard for operating the device. As a result of this work is realized and measured system design, which achieved relativem low levels of output ripple, short reaction time on change of load, but slower reaction of a current limit. Some parameters has not been entirely fine-tuned, especialy speed of reaction of current limit, amplitude of output distortion volage and stability diring short circuit on output clamps.

National Repository of Grey Literature : 12 records found   1 - 10next  jump to record:
See also: similar author names
7 MATĚJŮ, Jan
2 MATĚJŮ, Jana
1 Matějů, Jakob
13 Matějů, Jakub
5 Matějů, Jiří
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