The application of Item Response Theory on a teaching strategy profile questionnaire

<p>Abstract</p> <p>Background</p> <p>In medical education research, various questionnaires are often used to study possible relationships between strategies and approaches to teaching and learning and the outcome of these. However, judging the applicability of such questionnaires or the interpretation of the results is not trivial.</p> <p>Methods</p> <p>As a way to develop teacher thinking, teaching strategy profiles were calculated for teachers in a research intensive department at Karolinska Institutet. This study compares the sum score, that was inherent in the questionnaire used, with an Item Response Theory (IRT) approach. Three teaching dimensions were investigated and the intended sum scores were investigated by IRT analysis.</p> <p>Results</p> <p>Agreements as well as important differences were found. The use of the sum score seemed to agree reasonably with an IRT approach for two of the dimensions, while the third dimension could not be identified neither by a the sum score, nor by an IRT approach, as the items included showed conflicting messages.</p> <p>Conclusions</p> <p>This study emphasizes the possibilities to gain better insight and more relevant interpretation of a questionnaire by use of IRT. A sum score approach should not be taken for granted. Its use has to be thoroughly evaluated.</p

Symmetric Assembly Puzzles are Hard, Beyond a Few Pieces

We study the complexity of symmetric assembly puzzles: given a collection of simple polygons, can we translate, rotate, and possibly flip them so that their interior-disjoint union is line symmetric? On the negative side, we show that the problem is strongly NP-complete even if the pieces are all polyominos. On the positive side, we show that the problem can be solved in polynomial time if the number of pieces is a fixed constant

Determining the Air Gap Length of an Axial Flux Wound Rotor Synchronous Generator

The&nbsp; air&nbsp; gap&nbsp; length&nbsp; of&nbsp; the&nbsp; designed&nbsp; axial&nbsp; flux&nbsp; wound&nbsp; rotor&nbsp; (AFWR)&nbsp; synchronous&nbsp; generator&nbsp; is&nbsp; determined&nbsp; properly according to the design parameters. One of the distinct advantages of&nbsp; an axial&nbsp; flux (AF)&nbsp; machine is&nbsp; its adjustable air gap. An AF generator&rsquo;s performance might be controlled by adjusting its air gap. The designed generator has a small-scale capacity that has 1 kW, 380 V, and 50 Hz. The windings are laid into slots made from laminated core. The slots are carved in the face of the stator and rotors. The generator has a single-double-sided slotted wound stator sandwiched between twin rotors. The effect of air gap changes on its&nbsp; performance can be seen from the calculation results using the given equations. The results reveal electric quantities suited to the machine&rsquo;s effective performance. The smaller the air gap,&nbsp; the&nbsp; greater&nbsp; the&nbsp; efficiency&nbsp; and&nbsp; power&nbsp; factor&nbsp; and&nbsp; the&nbsp; smaller&nbsp; the&nbsp; armature&nbsp; current&nbsp; and&nbsp; voltage.&nbsp; The&nbsp; efficiency&nbsp; and armature current for 0.1 cm air gap are 85.30 % and 1.815 A, respectively

Experimental Evidence of Quantum Confinement Impairment In The Optical Properties of Annealed Lead Sulphide Thin Film

Recent characterizations of compounds are undoubtedly one of the avenues for the emergence of new semiconducting-light emitting diode (LED) devices. The industrial application of the lead sulphide thin film has been proposed. The lead sulphide thin film was grown by Chemical Bathe Deposition Technique (CBDT) and annealed at four temperatures of 100oC, 150oC, 200oC and 250oC. The samples were analyzed via the 6045 U-V spectrometer. The results shows that PbS thin film has a low transmittance value ranging from 0.204709% to 0.85722%; absorbance value ranging between 3.026% and 3.564%; reflectance value ranging from 81% to 114%; direct band gap was between 1.66eV to 1.78eV. Hence, the calculated refractive index ranges from 1.67 to 1.669. The evidence of quantum confinement impairment in each annealed samples was proofed. This shows that the optical tuning of the lead sulphide is dependent on the thermal control of its constituent's diamete

Meningkatkan Kemampuan Pemahaman Konsep Matematika Melalui Model Pembelajaran Realistic Mathematics Education Menggunakan Alat Peraga Kubus dan Balok

The purpose of this study was to improve the understanding of mathematical concepts of students through Realistic Mathematics Education. Learning model assisted by teaching aids on cube and block material. This research is classroom action research. The research subjects were class VIIIA students for the 2021/2022 academic year with 26 people. The techniques used in data collection are observation and tests. The data analysis technique in this study is data analysis of teacher observations, student observations and tests of understanding mathematical concepts. The research procedure includes planning, implementation, observation, and reflection. The study consisted of 2 cycles. Realistic Mathematics Education learning assisted by teaching aids on cube and block material, as long as this research has been running according to the learning implementation plan, has succeeded in creating a conducive learning situation, and increasing students' understanding of concepts. The results showed that the ability to understand mathematical concepts in the first cycle was 50% less criteria, and in the second cycle, 81% good criteria. The results of observations of teachers' teaching skills when managing learning has increased. In the first cycle, it reached 69.12% good criteria, while the second cycle reached 85.28% excellent criteria. The results of observations of student learning activities have increased. From the first cycle, the percentage is 63.75 good criteria, while the second cycle is 83.75% excellent criteria

Analisis Kinerja Pembangkit Listrik Energi Terbarukan Pada Model Jaringan Listrik Mikro Arus Searah

This paper aims to analyze the performance of the Renewable Energy Power Plants which are consist of PLTS and PLTB 12V/100W that supplies power into DC microgrid. Before supplying the power, each power plant was tested in no-load and on-load conditions. On the DC microgrid is tested burden sharing between the PLTS and PLTB by considering the capacity of each battery. The PLTS's test results indicate that 12V 80W of solar cell that facing to the east direction on June 2010was producing electric current in the largest average number (1.954 A) and charging the 12V, 45 Ah of battery for 23 hours, faster than if faced it to the other direction. The voltage decreased occurring on PLTS and PLTB by 9.4% and 8.4% of the nominal voltage of 12V when they burdened with 80% of nominal load 100W. This happens due Load which connected into the direct current electricity micro grid, get the power supply from PLTS and PLTB on which each power plant equipped with the batteries at the same capacity 12V 45Ah. On no-load conditions, PLTS and PLTB charging the battery, while on loaded conditions, the electric current which generated by both power plants flowed into the load, with the division of electric power that supplied into the load depends on each battery's power. Power plants with a larger charging battery supplying power greater than the power plants with a smaller charging battery. Keywords Renewable energy, microgrid, direct current, the performanc