The Enlightenment concept of education in the Serbs began to develop late at the end of the 18th century. The Enlightenment concept of education was created and developed as an integral part of the ...humanisticenlightenment movement. Its basic source are philosophical and sociological ideas of many European enlighteners and advanced European thoughts. Such a concept was not genuine, but it was an epochal advance for Serbian pedagogy, school, and education. A great number of Serbian enlighteners tried to create a new concept of education. They believed in the unlimited powers of education and felt that only education could change society. The first Serbian educator and teacher St. Sava, the first Serbian rationalist Dositej Obradovic and an elite critic and reformer of the school, Vasa Pelagic, gave a special contribution to the constitution of the new concept of education. In this paper, the author presents the basic pedagogical ideas of Serbian enlighteners, the understanding of the essence of education and its goals as well as the views of the new school.
A vegetation survey in northeastern Croatia explored the influence of intensive arable farming on the weed community in relation to the crop edge and adjacent field margin. A total of 141 vascular ...plants were recorded, and significant differences among the species appear in the field margins (134) as compared to the crop edges (109) and middle of the fields (49). Native plants predominated (83.7%), but among non-natives, the most abundant were Ambrosia artemisiifolia L., Abutilon theoprasti Med. and Veronica persica Poir., with the highest cover values inside the cropped areas, particularly during spring sowing of row crops. The most diverse (having significantly higher Evenness and Shannon?s diversity index) was the community from the field margin, followed by the weed community that developed on the crop edges. Three distribution patterns were observed: weeds typically limited to the crop area, weeds limited to the non-crop area and weeds with some ability to spread from the field margins. Major variations in species composition were identified according to sowing season and crop type. Wind dispersal annuals with light- and nitrogen-demands were associated with disturbed, tilled habitats, while perennials with higher requirements for moisture and other than a wind mode of dispersal, were associated with the field margins.
nema
Field margins are pollinator-friendly habitats and important refuges for many pollinators. As a valuable food resource throughout the vegetation season, not just when crop species are in flower, ...field margins need to be protect or restore in areas of intensive farming. This paper examines the floristic and functional structure of weed communities on field margins in the northeastern part of the Republic of Croatia. A phytocoenological survey was conducted during the summer period of 2017 and 2018. A total of 32 field margins was analyzed for species richness, abundance and their role for entomofauna. Floristically rich field margins consist of 72,6% plant species beneficial to pollinators. Foraging period can be stretching throughout the year, but stabile and high flowering period is from May to end of September. Among highest ranked honeybee plants, several invasive species with significant relative abundance are: Solidago gigantea, Asclepias syriaca and Amorpha fruticosa who pose a serious threat to plant biodiversity. Positive role of vegetation from field margins was not valuable for pollinators only, but they also serve as supply the substrates that provide a shelter and nesting sites.
A short overview of the emission spectroscopy methods for measuring the macroscopic electric field in high pressure discharges with helium is given. The occurrence of macroscopic electric field is a ...consequence of the space charge buildup. It is a common feature of discharge sheaths, streamer heads and double layers. The spectroscopic methods are based on polarization-dependent Stark splitting and shifting of atomic lines in the presence of a relatively strong electric field. For high pressure discharges Stark shifting of helium lines and their forbidden counterparts is used. The advantage of Stark methods is their ab initio basis which makes them independent on other plasma parameters. A different method for field measurement, based on the helium line ratio, can be applied in cases where the Stark method cannot be used.
Abstract This paper analyses the floristic biodiversity of weed communities in the arable lands of the Istrian peninsula during a twelve year period (2005–2017). A total of 50 fields were surveyed ...for each sampling time using the seven-degree Braun-Blanquet cover abundance scale in the following agricultural categories: a) permanent crops (vineyards/olive groves), b) alfalfa fields, c) cereals, d) row crops and e) ruderal areas. The taxonomic identification was performed during the full development of vegetation, for cereals in June and July, and for the rest – in August and September. A total of 175 weed species were determined during both study periods with Asteraceae and Poaceae families as the most abundant. Altogether, therophytes were dominant in both surveys, followed by hemycryptophytes and geophytes. Variations in species composition were visible in both study periods (2005 and 2017) as well as in the selected habitat types. Exclusive species were found in addition to those that were common for both surveys. Changes in species composition between 2005 and 2017 referred to the difference in row spacing in earlier period, and ruderal vs. agricultural habitats in the recent survey. The differences in phenological traits between the past and present surveys were greatest for germination season in permanent crops and row crops, flowering start for permanent crops, flowering period for ruderal area and weed height for permanent crops. Significant differences between the past and present survey for other plant traits did not occur.
U istoriji pedagogije značajnomjesto zauzimaju prosvjetiteljskeideje koje su nastale kao reakcija natradicionalnu školu i njene odrednice.Kritikujući staru tradicionalnuškolu te vjerujući u ...neograničenemoći vaspitanja i obrazovanja prosvjetiteljisu smatrali da je uz pomoćreforme škole moguće stvoriti boljeljude i novo, humanije društvo. Ovakvomišljenje je zastupao i Vasa Pelagićkoji je izložio niz progresivnihideja uz čije bi ostvarivanje po njegovommišljenju moglo doći do preobražajavaspitanja i obrazovanjamladih.U vremenu u kojem je živio VasaPelagić ovakve ideje su nazivaneutopističke, osuđivane su, kritikovanezbog čega mnoge od njih nisu bileprihvaćene i praktično ostvarene.U želji da saznamo da li su i ukojoj mjeri navedene ideje danas aktuelneopredjelili smo se za istraživanjeznajući da su takva istraživanjau današnjem vremenu rijetkost.Cilj ovog rada jeste da ukaže ukojoj su mjeri aktuelne ideje VasePelagića, odnosno koliko su praktičnoostvarene u današnjim školama.Autor je u prvom dijelu rada daopregled ideja Vase Pelagića koje seodnose na nastavu, nastavne sadržajei učitelja. U drugom dijelu radaprikazuju se rezultati empirijskog istraživanjao aktuelnosti navedenihideja koje je sprovedeno među učenicimau Osnovnoj školi BorisavStanković u Banjoj Luci (N=216).Rezultati istraživanja pokazuju dasu mnoge ideje Vase Pelagića aktuelnešto možemo zahvaliti futurološkojviziji ovog istaknutog prosvjetitelja.
A compact, repetitive Marx generator with an external trigger is constructed and coupled with a wire-to-plate corona reactor for a positive pulsed corona discharge studies. The reactor resistance and ...capacitance behavior during the pulse was observed. It was found that the reactor's capacitance increases three times during the pulse due to the streamer propagation from anode to grounded electrode. Using the time development of the capacitance and resistance during the pulse and the reactor inter-electrode distance, the streamer velocity has been calculated to be 1 × 106 m/s, for system arrangement presented in this work. As an indicator of chemical activity of pulsed corona, ozone production was measured. Emission spectroscopy measurements in the UV region were performed to detect species that appear in the discharge and to determine vibrational and rotational temperatures, which are found to be 3200 K and 340 K respectively. As a measure of pollution control potential of the constructed pulsed corona system, NO oxidation efficiency was investigated and compared with results presented in literature. It was shown that pulsed corona systems with significantly longer pulse durations are competitive with several times shorter pulse duration systems, which implies that chemical efficiency of secondary streamers is comparable with efficiency of primary streamers.
► Reactor capacitance rises during the streamer propagation. ► Streamer velocity can be obtained from the electrical measurements. ► Longer pulse duration has the same energetic efficiency like the shorter one.
PDF
