Supportive methods for assessing effective porosity and regulating karst aquifers

Regulation of a karst aquifer implies engineering interventions designed to control its flow and manage its water reserves. One of the most important prerequisites for the feasibility and suc­cess of regulation projects is proper assessment of aquifer ef­fective porosity (storativity) and accumulated groundwater reserves. This paper is focused on several specific methods whichcan contribute to a reliable assessment of the size and volume of effective storage in karst: cave diving survey, camera logging of cavities, stochastic analysis of discharge regime and 3D modelling of karst interior. The application of these meth­ods on selected test sites in Montenegro, Algeria and Serbia are described. These methods were applied as part of the researchprogramme conducted in the catchment of Mlava Spring, the largest spring in the Carpathian karst of Serbia. The results ob­tained by the stochastic analyses of the spring’s discharge re­gime, as well as siphon diving of the spring and 3D modelling for reconstruction of conduits networks in karst interior are particularly important

Beogradski inventar za procenu ličnosti adolescenata kao most između procene ličnosti dece i odraslih

Personality inventories for assessment and study temperament and character of adolescents, an age critical for the finalisation of both normal and pathological mental development, have not been specifically developed. In this paper, we introduce a new personality inventory based on Cloninger's Psychobiological model of personality to assess adolescents from 14 to 18 years of age (the Belgrade Adolescent Personality Inventory - BAPI), which bridges the gap between personality assessment in children and adults. The BAPI is a 46-item Likert scale inventory derived from previous studies using the TCI and JTCI on the Serbian sample. The psychometric properties of the BAPI were tested on the sample of 535 secondary school students in Serbia, aged 15 to 16. In order to assess the fit of the model, the Confirmatory factor analysis (CFA) was performed. The differences between sexes were analysed by MANOVA, while the Latent class analysis (LCA) was applied in order to identify different adaptation profiles among adolescents. The BAPI scales had a satisfactory internal consistency (.66 - .80.) considering the small number of items (5-6) in each scale. The confirmatory factor analysis (CFA) generally supported the main dimensions of temperament and character, as postulated by Cloninger. The only exception was Novelty Seeking, which best fitted a two-factor solution, Explorative curiosity and Impulsivity, separating the 'good' (curious, inquisitive, creative) and 'bad' (impulsive, impatient, disorderly) facets of this trait. Such polarity of Novelty Seeking could be specific for personality development and behaviour disorders in adolescence. The LCA differentiated the personality profiles of well-adapted adolescents from those at risk for maladaptation that manifested low character traits, lack of Persistence and high Novelty seeking Impulsivity subscale. The results support the construct validity of the BAPI and thus provide the basis for its practical application in personality assessment of adolescents and contribute to the theoretical understanding of personality structure and the risk of psychopathology in adolescence.S obzirom da postoji nedostatak namenski konstruisanih inventara za procenu i proučavanje ličnosti adolescenata koji su u uzrastu ključnom za završetak kako normalnog, tako i patološkog mentalnog razvoja, u radu je predstavljen novi inventar ličnosti zasnovan na Klonindžerovom Psihobiološkom modelu ličnosti. Beogradski Inventar Ličnosti Adolescenata (BILA) koristi se za procenu adolescenata uzrasta od 14 do 18 godina i trebalo bi da premosti jaz između procene ličnosti kod dece i odraslih. Upitnik obuhvata 46 stavki Likertovog tipa i nastao je na osnovu prethodnih istraživanja u kojima su korišćeni TCI i JTCI na uzorku naših ispitanika. Psihometrijske karakteristike upitnika ispitane su na uzorku od 535 srednjoškolaca iz Srbije, starosti od 15 do 16 godina. Kako bi se utvrdila adekvatnost modela, urađena je konfirmatorna faktorska analiza. U cilju analize polnih razlika korišćena je MANOVA, dok je analiza latentnih klasa primenjena kako bi se utvrdilo da li se mogu izdvojiti specifični profil ličnosti adolescenata iz uzorka iz opšte populacije. Skale upitnika pokazale su zadovoljavajuću internu konzistenciju (.66 - .80), posebno imajući u vidu mali broj stavki (5-6) u svakoj skali. Konfirmatorna faktorska analiza je načelno potvrdila glavne dimenzije temperamenta i karaktera onako kako ih je definisao Klonindžer. Jedini izuzetak je bio u slučaju Potrage za novinama, za koju je podesnije dvofaktorsko rešenje. Potragu za novinama čine Eksplorativna radoznalost i Impulsivnost koie razlikuju 'dobre' (znatiželjan, radoznao, kreativan) i 'loše' (impulsivan, nestrpljiv, haotičan) odlike ove dimenzije. Ovaj polaritet Potrage za novinama mogao bi da bude specifičan za razvoj ličnosti i poremećaja u ponašanju tokom adolescencije. Analizom latentnih klasa utvrđene su razlike između profila ličnosti dobro adaptiranih adolescenata i onih kod kojih postoji rizik za razvoj problema u ponašanju, a koji imaju nizak skor na crtama karaktera, niži stepen Perzistencije i povišenu Impulsivnost. Dobijeni rezultati potvrđuju konstrukt validnost BILA upitnika i što omogućava njegovu praktičnu primenu u proceni ličnosti adolescenata, pružajući doprinos teorijskom razumevanju strukture ličnosti i rizika od psihopatologije u adolescenciji

Razlike u temperamentu i karakteru kod adolescenata sa raznim poremećajima ponašanja

Background/Aim. Adolescence is characterized both by a large developmental potential and by an increased risk for emergence of different forms of psychopathology. International classifications of mental disorders recognize the psychopathology of adolescence at the age of 15-18 through the categories of conduct disorders and some forms of addiction: chemical and non-chemical. The aim of this research was to analyse the personality structure among four groups of adolescents manifesting different types of conduct disorder based on Cloninger's Psychobiological theory of personality. Methods. The research sample consisted of 140 respondents at the age of 16-18, divided into five groups: 30 respondents manifesting socialized conduct disorder, 20 adolescents in conflict with the law, 30 respondents manifesting abuse of psychoactive substances, 30 respondents with the problem of the Internet addiction and 30 from general population. The Belgrade Adolescent Personality Inventory (BAPI) questionnaire was used for the purpose of assessment of personality. Multivariate analysis of variance (MANOVA), followed by univariate analysis of variance (ANOVA) was used to examine differences between the given groups of adolescents. Results. The results of MANOVA show differences in the personality structure among the groups, both in the dimensions of temperament, F (20,418.84) = 2.71, p lt 0.001, Wilks's lambda 0.67, and in the dimensions of character, F (12,344.24) = 3.27,p lt 0.001, Wilks's lambda is 0.75. Socialized conduct disorder is characterized by low self-directedness and average cooperativeness. Adolescents in conflict with the law have the lowest persistence, together with low self-directedness and cooperativeness. Adolescents abusing psychoactive substances have low harm avoidance and self-transcendence. Adolescents with Internet addiction are characterized by high novelty seeking (impulsivity and curiosity), low self-directedness and the lowest cooperativeness. Conclusion. The results show that the dimensions of personality can play an important role in etiopathogenesis of various disorders in adolescents.Uvod/Cilj. Adolescenciju karakteriše veliki razvojni potencijal, ali i pojačani rizik od formiranja različitih vidova psihopatologije. Psihopatologiju adolescencije uzrasta od 15 do 18 godina, međunarodne klasifikacije mentalnih poremećaja prepoznaju kroz kategorije poremećaja ponašanja i neke vidove bolesti zavisnosti: hemijskih i nehemijskih. Cilj istraživanja bio je da se na osnovu Klonindžerove psihobiološke teorije ličnosti analizira struktura ličnosti kod četiri grupe adolescenata koji manifestuju različite oblike poremećaja ponašanja. Metode. Uzorak istraživanja sastojao se od 140 ispitanika uzrasta od 16 do 18 godina, podeljenih u pet grupa: 30 ispitanika koji su manifestovali socijalizovani poremećaj ponašanja, 20 adolescenata sa poremećajem ponašanja u sukobu sa zakonom, 30 ispitanika sa problemom zloupotrebe psihoaktivnih supstanci, 30 ispitanika sa problemom zavisnosti od interneta i 30 ispitanika kontrolne grupe. Za procenu strukture ličnosti korišćen je upitnik Belgrade Adolescent Personality Inventory (BAPI). Razlike između grupa adolescenata ispitane su multivarijatnom (MANOVA) i univarijatnom (ANOVA) analizom varijanse. Rezultati. Rezultati multivarijatne analize varijanse pokazuju da postoje razlike u strukturi ličnosti između svih grupa, kako na dimenzijama temperamenta, F(20,418.84) = 2.71,p lt 0.001, Vilksova lambda 0,67, tako i na dimenzijama karaktera, F (12,344.24) = 3,27, p lt 0,001, Vilksova lambda 0,75. Socijalizovani poremećaj ponašanja karakteriše niska samousmerenost, Ali prosečna kooperativnost. Adolescenti u sukobu sa zakonom imaju najnižu perzistenciju, kao i nisku samousmerenost i kooperativnost. Adolescenti koji zloupotrebljavaju psihoaktivne supstance imaju nisko izbegavanje štete i autotranscedenciju. Za adolescente sa internet zavisnošću karakteristična je visoka potraga za novinama (impulsivnost i radoznalost), niska samousmerenost i najniža kooperativnost. Zaključak. Rezultati ukazuju da dimenzije ličnosti mogu igrati značajnu ulogu u etiopatogenezi različitih poremećaja adolescenata

History of chemistry in the pre-service chemistry teachers education

History of chemistry could be an important part of the curriculum for pre-service chemistry teachers’ education. This allows them the deeper understanding of nature of science and scientific work, as well as to build a base for future planning the contextual approaches through which their school students could learn about nature of science. History of Chemistry is taught in the fourth year within the integrated academic studies curriculum (300 ECTS) for chemistry teachers’ education at the Faculty of Chemistry University of Belgrade. During the last three school years at the very beginning of the course of History of Chemistry the estimation of the knowledge of some historical facts, such as the scientific contribution of Robert Boyle, Henry Cavendish, Joseph Priestley, Antoine Lavoisier, John Dalton, Jöns Jacob Berzelius, Alessandro Volta, Michael Faraday was conducted. These scientists were chosen according to the previous analysis of the syllabuses of different secondary school and university chemistry and physics subjects. In this way, we were able to examine whether students pay attention to the work of scientists when they study various subjects from chemistry and physics domain. In addition, we asked the students whether they read texts from the history of science, what was the most important scientific discovery from their point of view, who was the most significant scientist in their opinion, whether they had a role model among scientists. Also, we asked students to describe an experiment that they knew from the history of science. The obtained results showed that students, future chemistry teachers, have developed certain attitudes about chemistry as a science, but they possess little knowledge about the scientific work of scientists. These findings are later useful for the lessons and workshops planning within the course of history of chemistry

Crane operators' anthropomeasures factors identification

Cilj ovog rada je primena metode zasnovane na viševarijantnoj statističkoj tehnici u cilju određivanja kritičnih dimenzija kabine krana, sa maksimalnom ergonomskom prilagođenošću radi smeštaja što šireg opsega populacije i veće bezbednosti rada. Korišćena je viševarijantna tehnika - faktorska analiza. Rezultati ovog istraživanja sprovedenog na uzorku 83 operatora pokazuju da se faktorskom analizom veći broj faktora raspoređuje u trodimenzionalnom prostoru. Rezultati ovog rada omogućavaju projektantima rešavanje dilema, a zahvaljujući rezultatima ovog rada mogu se projektovati kabine krana sa manje stresnim položajem operatera i povećanom produktivnosti i bezbednosti.Purpose of this paper is application of method based on multivariate statistical technique in order to determine critical dimensions of the crane cabin, which would maximize adjustability and ergonomics of the product, resulting in accommodation of wider range of the population and greater safety while operating. Multivariate statistical technique used for this purpose is factor analysis. Results of this research, conducted on a sample consisted of 83 crane cabin operators, showed that while designing a working space critical anthropomeasures take three-dimensional space, while their influence contributions in each dimension are determined with factor analysis. Results of this work are expected to be useful for industry in a way such that crane cabins' designers can troubleshoot the dilemmas they encounter in their job. Using findings of this survey might lead to new designs of cabins that will offer less strenuous postures of operator, which consequently will improve productivity and safety

The programme for professional development of chemistry teachers’ assessment competency

The aim of this paper is to investigate the effects of the programme for professional development of chemistry teachers on their competencies for conducting formative and summative assessment in chemistry teaching. The programme participants were 30 chemistry teachers from primary and secondary schools. Data were collected using a questionnaire at the beginning and at the end of the programme implementation. The programme included four workshops with the same structure: the introduction, group work and the discussion of the results obtained through group work. The workshops focused on: i) the assessment as a support for chemistry learning; ii) the harmonization of teaching and learning activities, formative and summative assessment, feedback from formative assessment and the criteria used to evaluate students in summative assessment; iii) the evaluation of the validity of tasks used for formative and summative assessment according to the curricula aims and the educational standards; iv) designing tasks for monitoring students’ progress towards certain educational standards. Teachers’ responses show the impact of the programme for the development of their competencies for assessment, particularly regarding formative and summative assessment and designing various kinds of assessment in accordance with the achievement standards

Crane operators' anthropomeasures factors identification

Cilj ovog rada je primena metode zasnovane na viševarijantnoj statističkoj tehnici u cilju određivanja kritičnih dimenzija kabine krana, sa maksimalnom ergonomskom prilagođenošću radi smeštaja što šireg opsega populacije i veće bezbednosti rada. Korišćena je viševarijantna tehnika - faktorska analiza. Rezultati ovog istraživanja sprovedenog na uzorku 83 operatora pokazuju da se faktorskom analizom veći broj faktora raspoređuje u trodimenzionalnom prostoru. Rezultati ovog rada omogućavaju projektantima rešavanje dilema, a zahvaljujući rezultatima ovog rada mogu se projektovati kabine krana sa manje stresnim položajem operatera i povećanom produktivnosti i bezbednosti.Purpose of this paper is application of method based on multivariate statistical technique in order to determine critical dimensions of the crane cabin, which would maximize adjustability and ergonomics of the product, resulting in accommodation of wider range of the population and greater safety while operating. Multivariate statistical technique used for this purpose is factor analysis. Results of this research, conducted on a sample consisted of 83 crane cabin operators, showed that while designing a working space critical anthropomeasures take three-dimensional space, while their influence contributions in each dimension are determined with factor analysis. Results of this work are expected to be useful for industry in a way such that crane cabins' designers can troubleshoot the dilemmas they encounter in their job. Using findings of this survey might lead to new designs of cabins that will offer less strenuous postures of operator, which consequently will improve productivity and safety

Mineralogical characteristics of slag (from the Flotation plant of RTB Bor) granulated in the laboratory conditions

A sample of slag from the Flotation Bor, RTB Bor, was mineralogical tested after granulation in the laboratory conditions. Minerals contained in the sample of granulated slag are: fayalite and ferrite that form the basis with rarely sprayed fine particles of magnetite, pyrite, chalcopyrite, bornite, copper matte and elemental - native copper [6, 7]. Granulation of slag was conducted in the laboratory conditions on the device specially designed for this purpose

History of chemistry in chemistry education – chemistry teachers attitudes

Ideja o uključivanju istorije i filozofije nauke u kurikulume prirodnih nauka promoviše se decenijama. Primena istorije i filozofije nauke u nastavi/učenju pririodnih nauka okarakterisana je kao dobar način za poboljšanje naučne pismenosti učenika. Neke od prepreka za takav pristup u nastavnoj praksi su: perspektive nastavnika, njihova uverenja, razumevanje glavnih ideja i ciljeva nastave/učenja, kao i epistemološka shvatanja.1 U istraživanju, u kome je učestvovalo 272 nastavnika hemije osnovnih škola u Srbiji, putem upitnika ispitani su: stavovi nastavnika o sadržajima iz istorije hemije i efektima primene tih sadržaja u nastavi na učeničko razumevanje hemije, načini kako nastavnici prezentuju nauku učenicima, učestalost primenjivanja metoda nastave/učenja i aktivnosti koje podstiču razvoj naučnog rezonovanja kod učenika. Ispitano je i da li su nastavnici tokom inicijalnog obrazovanja učili sadržaje iz istorije i filozofije nauke i da li imaju uzore među naučnicima. Na osnovu dobijenih rezultata može se zaključiti da nastavnici uviđaju potencijal sadržaja iz istorije hemije za bolje razumevanje hemije, ali da takve sadržaje u praksi nedovoljno primenjuju. Rezultati istraživanja ukazuju i na nedostatak kurseva iz istorije i filozofije nauke u toku inicijalnog obrazovanja nastavnika.The idea of involving the history and philosophy of science in the science curricula has been promoting for decades. The involving of the history and philosophy of science in the science classes is characterized as a good way to improve scientific literacy of students. Some of obstacles for this approach in teaching practice are: the perspectives of teachers, their beliefs, understanding of the main ideas and goals of teaching/learning and epistemological understanding.1 In the research with 272 chemistry teachers from primary schools in Serbia, questionnaire was used to examine: the attitudes of teachers about the contents of the history of chemistry and about the effects of application these contents in teaching practice on student’s understanding of chemistry, the ways in which teachers present science to students, the frequency of application teaching/learning methods and activities that encourage the development of scientific reasoning of students. Also, we examined whether the teachers learned the contents of the history of chemistry and philosophy of science during their initial education and their personal preferences about scientists. Based on the results it can be concluded that teachers recognize the potential of the history of chemistry content for better student’s understanding of chemistry. However, they don’t apply these contents in practice enough. The results indicate the lack of courses in the history and philosophy of science during initial education of chemistry teacher

Students' Argumentation Skills Expressed in the Context of the History of Chemistry

The development of students’ abilities to formulate arguments, reason and think critically in scientific context is one of the goals of science education [1]. Episodes from the history of chemistry can serve as that scientific context. The research was conducted with the aim of examining students’ ability to apply the newly acquired knowledge about composition, structure and general properties of organic compounds to formulating arguments for and against the views of the scientists who had contributed to the development of organic chemistry in the 19th century. A total of 43 students aged 14 participated in this research in the school year 2017/18. Firstly, the students individually read the text about the composition, structure and general properties of organic compounds and how these compounds are different from inorganic compounds. After that, they listened to audio-voice recordings in which the views of scientists who are given the credit for the development of organic chemistry were interpreted (Jоns Jacob Berzelius, Friedrich Wоhler, Antoine - Laurent de Lavoisier, Friedrich August Kekulе von Stradonitz and Archibald Scott Couper). After each recording, students were expected to individually estimate whether the presented views of the scientists would be acceptable today or not and to write arguments for and against. The students were given the opportunity to use the text they had previously read as the source of information for formulating arguments. In this approach the students were in a position to apply the acquired knowledge in order to estimate the views of the scientists, and to improve their high-order cognitive skills. A conclusion supported by at least one justification was labelled as an argument in the analysis of students’ answers in this research. The structure and contents of arguments were evaluated jointly on a 0-to-5 scale according to the modified version of the methodology described in the literature [2]. One third of the total number of produced arguments contains a conclusion, justification and additional explanation of the justification. At the same time, this kind of argument is the most frequent. Based on the obtained results it can be concluded that the episodes from the history of chemistry in combination with some other sources of information can serve as a fruitful context for formulating arguments and stimulating high-order cognitive skills. References: [1] D. Katchevich, A. Hofstein, R. Mamlok-Naaman, Argumentation in the Chemistry Laboratory: Inquiry and Confirmatory Experiments, Res. Sci. Educ. 43 (1) (2013) 317-345. [2] A. Zohar, F. Nemet, Fostering Students’ Knowledge and Argumentation Skills through Dilemmas in Human Genetics. J. Res. Sci. Teach. 39 (1) (2002) 35-62