376 research outputs found
Changes of Students’ Alternative Conceptions in Physics Learning - Effects of Traditional Teaching and Active Learning Methods
У раду је приказано истраживање реализовано са циљем проширивања знања о феномену алтернативних концепција у настави физике, са нагласком на алтернативне концепције о пливању и тоњењу тела и поређење ефеката традиционалне наставе и метода активног учења на њихово превазилажење. Резултати истраживања показују широку заступљеност алтернативних концепција о пливању и тоњењу тела код испитиваних ученика седмог разреда основне школе непосредно пре реализовања наставе о сили потиска и појавама везаним за њу. Поређењем постигнућа ученика на завршном дијагностичком тесту у односу на уводни утврђено је да постоје статистички значајне разлике у ефекту традиционалног модела наставе и модела наставе усмерене на активно учење о сили потиска и појавама везаним за њу на превазилажење алтернативних и усвајање научних концепата услова за пливање и тоњења тела: У контролној групи средњи нормализовани напредак износи 0.04±0.25, а у експерименталној 0.84±0.21. Предност применеметода активног учења над традиционалним приступом настави додатно потврђују разлике у постигнућу ученика у погледу примене и трајности усвојених знања о сили потиска и појавама везаним за њу. Основне импликације истраживања односе се на неопходност уважавања савременог конструктивистичког погледа на природу учења у наставном процесу, односно примену наставних приступа усмерених на активно учење и развој широког спектра компетенција.U radu je prikazano istraživanje realizovano sa ciljem proširivanja znanja o fenomenu alternativnih koncepcija u nastavi fizike, sa naglaskom na alternativne koncepcije o plivanju i tonjenju tela i poređenje efekata tradicionalne nastave i metoda aktivnog učenja na njihovo prevazilaženje. Rezultati istraživanja pokazuju široku zastupljenost alternativnih koncepcija o plivanju i tonjenju tela kod ispitivanih učenika sedmog razreda osnovne škole neposredno pre realizovanja nastave o sili potiska i pojavama vezanim za nju. Poređenjem postignuća učenika na završnom dijagnostičkom testu u odnosu na uvodni utvrđeno je da postoje statistički značajne razlike u efektu tradicionalnog modela nastave i modela nastave usmerene na aktivno učenje o sili potiska i pojavama vezanim za nju na prevazilaženje alternativnih i usvajanje naučnih koncepata uslova za plivanje i tonjenja tela: U kontrolnoj grupi srednji normalizovani napredak iznosi 0.04±0.25, a u eksperimentalnoj 0.84±0.21. Prednost primenemetoda aktivnog učenja nad tradicionalnim pristupom nastavi dodatno potvrđuju razlike u postignuću učenika u pogledu primene i trajnosti usvojenih znanja o sili potiska i pojavama vezanim za nju. Osnovne implikacije istraživanja odnose se na neophodnost uvažavanja savremenog konstruktivističkog pogleda na prirodu učenja u nastavnom procesu, odnosno primenu nastavnih pristupa usmerenih na aktivno učenje i razvoj širokog spektra kompetencija.The thesis presents an investigation implemented with the goal of expanding knowledge on the phenomenon of alternative conceptions, with emphasis on alternative conceptions on floating /and sinking and on the comparison of effects of traditional teaching and active learning methods on overcoming those alternative conceptions.The results show wide presence of alternative conceptions on floating and sinking among the subject seventh grade primary school students, immediately before teaching them about buoyancy and related phenomena. By comparing students’ achievements on the final diagnostic test with the initial test results, statistically significant differences were found between the effects of traditional teaching model and the model focused on active learning about buoyancy and related phenomena on overcoming alternative and adopting scientific concepts ofconditions leading to floating and sinking: in the control group, the average normalized gain is 0.04±0.25, and in the experimental group it is 0.84±0.21 . The advantage that active learning methods have over traditional teaching approach is additionally confirmed by differences in students’ achievements with regards to the application and long-term retention of adopted knowledge on buoyancy and related phenomena. Basic implications of the research are the need to take note of modern constructivistic view on the nature of learning in the teaching process and of the application of teaching approaches aimed at active learning and the development of a wide spectrum of competences
Professional competence of primary and secondary school teachers as a factor that determines attitude toward inclusive education of blind students
Позитивни ставови наставника према инклузивном образовању слепих ученика представљају један од значајних предуслова за њихово активно укључивање у активности вршњака типичног развоја. Велики број истраживања указује на то да се негативни ставови могу довести у везу са недостатком професионалних компетенција наставника за рад са слепим ученицима.
Основни циљ овог истраживања био је да се утврде ставови наставника разредне и предметне наставе према инклузивном образовању у односу на њихове професионалне компетенције. Додатно, провераване су и разлике у погледу личне спремности наставника разредне и предметне наставе за рад са слепим ученицима. У истраживању је учествовало 49 наставника разредне и 59 наставника предметне наставе. Од инструмената примењивани су социо-демографки упитник и Упитник за процену ставова наставника према инклузивном образовању слепих ученика.
Резултати показују да су ставови наставника према инклузивном образовању слепих ученика генерално позитивни, али и да се значајне разлике у ставовима уочавају између наставника разредне и наставника предметне наставе. Добијени подаци указују на то да, у односу на наставнике предметне наставе, наставници разредне наставе испољавају значајно позитивније ставове, имају виши ниво професионалних компетенција за рад са слепим ученицима и испољавају значајно виши ниво спремности за будуће ангажовање у раду са овим ученицима. Практичне импликације ових резултата указују на потенцијалне тешкоће прилагођавања слепих ученика на други циклус образовања, које директно проистичу из мање позивних ставова и нижих нивоа професионалних компетенција предметних наставника. У оквиру анализе резултате дате су препоруке за унапређивање инклузивне праксе у нашој средини.Teachersʼ positive attitudes toward inclusive education of blind students are one of the most important preconditions for their active involvement in the activities of typicaly developing peers. А large number of researches indicate that negative attitudes can be related to the lack of professional competencies for working with blind students among teachers.
The main goal of this research was to determine the attitudes of primary and secondary school teachers towards inclusive education in relation to their professional competencies. In addition, the differences in terms of personal readiness of primary and secondary school teachers to work with blind students were checked.
In the research participated 49 primary school teachers and 55 secondary school teachers. Instruments used in this study were the socio-demographic questionnaire and the Questionnaire for the assessment of teachers' attitudes towards inclusive education of blind students were applied.
The results show that teachers attitudes towards inclusive education of blind students are generally positive, but also results reveal that significant differences in attitudes are observed between primary and secondary teachers. The obtained data indicate that, in relation to secondary teachers, primary school teachers show significantly more positive attitudes, have a higher level of professional competencies for working with blind students and show a significantly higher level of readiness for future engagement in working with these students.
The practical implications of these results point out the potential difficulties for adaption of blind students on the second cycle of education, which directly results from less positive attitudes and lower levels of professional competencies of secondary school teachers. As part of the analysis, the results provide recommendations for improving inclusive practices in our environment
Landslide stabilization in cut zone number 6 from km 28 + 478,00 to km 28 + 643,00
In the cut zone number 6 on E-80 Niš-Dimitrovgrad highway from km 28 +
478,00 to km 28 + 643,00 slope stability was affected causing mass movement. Additional
inclinometers measured the mass wasting thickness between 14 m and 25 m. The height
of the cut determined the slope protective backfilled gallery to be the best solution. The
paper presents the detailed geostatic calculation of landslide stabilization using computer
programs Plaxis 2D and RocScience Slide. Further, it shows the static calculation of the
protective gallery in the computer program Radimpex Tower 3D. Results confirmed that
the proposed structure was rigid enough to provide the necessary protection for the road
structure
Static calculation of stabilization of the landslide in cut 4 from km 878+650 to km 879+050
The paper presents retaining structure to stabilize the landslide in the middle
section from 878+775 to km 878+825, and slope protection on both left and right sides
in order to provide vertical cutting and excavation to the level of highway platform.
Retaining structure was designed as micro-pile wall with three different types of walls
depending on the pile position. Micro-pile is made from steel pipe dia. Ø139.6 mm and
8.8mm thick wall, which is filled with cement mortar of minimum strength 30 MPa. In a
constructive view, the designed retaining structure is a plate that is resting on the
continual tie beams, which are supported in discrete points by geotechnical anchors.
Calculation of stability and bearing capacity of protective structure was carried out in
several phases. Phases are modeled according to the technology of execution of works.
The calculation was performed in FEM program called Plaxis 2D. This calculation is
based on the finite element method, using an incremental, iterative process. Based on the
performed analysis, calculation of stability and bearing capacity, it can beconcluded
that designed support structure satisfies all the necessary conditions of stability and
bearing capacity
Detection of earthflow dynamics using medium-resolution digital terrain models: Diachronic perspective of the Jovac earthflow, Southern Serbia
The paper presents and discusses the landslide research procedure related to the topography before and after its occurrence, using the comparative analysis of two medium-resolution digital terrain models. The case study is the Jovac mega-landslide—the largest landslide to occur in Serbia in the last 100 years, active for three days in February 1977. The indicators used to determine the volume and movement mechanism were the spatial distribution of elevation differences within the two digital terrain models (DTM), and the analysis of geomorphological features before the landslide. The obtained elevation differences allowed the definition of the approximate landslide volume: 11.6 × 106 m3. All the data obtained indicate that the movement mechanism falls into the category of earthflow
INFLUENCE OF THE CUTTING PARAMETERS ON FORCE, MOMENT AND SURFACE ROUGHNESS IN THE END MILLING OF ALUMINUM 6082-T6
In this paper the performances, i.e. cutting force, moment and surface roughness, in the end milling of aluminum 6082-T6 with solid carbide end mill were measured and analyzed for different values of the cutting parameters: number of revolutions, feed rate and depth of cut. The cutting force and moment were measured using a Kistler piezoelectric dynamometer. Surface roughness was measured using a Mahr profilometer. The results were analyzed in the Minitab 17 software package, in order to determine the influence of the given factors on the performances and modeling of the milling process
Lokalne fondacije u Srbiji: Osnaživanje odozdo – uloga, izazovi i perspektive za razvoj lokalnih fondacija
The effects of immunocastration on male pig yield parameters and meat quality
The aim of this study was to evaluate the effects of immunocastration on pork meat and carcass quality, compared to meat from surgically castrated males and entire males. Ninety (Duroc x Pietrain) x (Landrace x Yorkshire) crossbred pigs were assigned to three experimental groups: surgically castrated males (barrows; castrated up to the seventh day of age), entire males (males), and vaccinated males (immunocastrates). Carcass and meat quality characteristics such as weight of hot and chilled carcass, meat yield, chilling loss and chemical parameters were examined. Surgically castrated pigs had significantly lower (p lt 0.01; p lt 0.05) weight before slaughter, than males and immunocastrates, and also lower (p lt 0.01) warm carcass weight than males. The average carcass meatiness of castrates was significantly lower (p lt 0.01) than the average meatiness of males and immunocastrates. Chilling loss of barrows was significantly lower (p lt 0.01) than chilling loss of males or immunocastrates. It was also found that the chilling loss of immunocastrates was significantly lower (p lt 0.05) than chilling loss of males. According to the results obtained, it can be concluded that immunocastration could be a good alternative to surgical castration considering meat and carcass quality characteristics
Experimental Investigation and Numerical Analysis of the Axial Load Capacity of Circular Concrete-Filled Tubular Columns
This paper focuses on the experimental investigation of the axial load capacity of CFT
(concrete-filled steel tube) columns under actual construction conditions during building reconstruction. A total of four samples were loaded up to failure. The varied parameters were the column length and absence/presence of the concrete infill within the steel tube. Further, the analysis is extended to developing a numerical model in the finite element-based software ABAQUS version 6.9. This numerical model includes material and geometrical nonlinearities and was validated with the experimental results. The contribution of the concrete core to the column capacity and the concrete core confinement effect are discussed. Finally, the column capacity was calculated according to several design codes: the Eurocode 4 with and without considering the confinement effect, American specifications, Australian standards, the American Institute of Steel Construction, and the Architectural Institute of Japan. The Eurocode 4 considering the confinement effect provides the closest results to those obtained in the tests
Investigation of intersubband transitions in wide bandgap oxide quantum well structures for optoelectronic device applications
There has been a surge of interest in recent years for the advancement of wide bandgap oxides such as zinc oxide (ZnO), magnesium oxide (MgO), gallium oxide (Ga2O3), etc. [1,2]. These materials have gained significant attention due to their distinctive characteristics and properties which are promising for the development of high-performance optoelectronic devices for applications in the domains of sensing, communications, and imaging. More specifically, Ga2O3 has wide bandgap energy of approximately 4.8 to 4.9 electron volts (eV), thus exhibiting exceptional transparency to ultraviolet (UV) radiation while displaying opaqueness to visible light [3]. On a parallel note, ZnO shows exemplary optical and electrical properties, including a high exciton binding energy and substantial oscillator strength [4]. Of particular significance is the exploration of intersubband transitions within multiple quantum well (MQW) structures, which offers a promising path for efficient light absorption and emission in the mid-infrared to terahertz spectral range. In this contribution we will numerically simulate the absorption spectra of the wide bandgap oxide MQW structures, adapting the approach for treating the light-matter interaction suitable when the depolarization field is the dominant many-body contribution, and discuss the potential applications in optoelectronic devices, specifically mid-infrared detectors, quantum cascade lasers, and modulators.IX International School and Conference on Photonics : PHOTONICA2023 : book of abstracts; August 28 - September 1, 2023; Belgrad
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