592 research outputs found
Experimental realization of the one qubit Deutsch-Jozsa algorithm in a quantum dot
We perform quantum interference experiments on a single self-assembled
semiconductor quantum dot. The presence or absence of a single exciton in the
dot provides a qubit that we control with femtosecond time resolution. We
combine a set of quantum operations to realize the single-qubit Deutsch-Jozsa
algorithm. The results show the feasibility of single qubit quantum logic in a
semiconductor quantum dot using ultrafast optical control.Comment: REVTex4, 4 pages, 3 figures. Now includes more details about the
dephasing in the quantum dots. The introduction has been reworded for
clarity. Minor readability fixe
Item analysis of multiple-choice questions in summative assessment for professional examination I of an outcome-based integrated MBBS curriculum
Background: This study presents an item analysis of multiple-choice questions (MCQ-Type A) used in the summative assessment for Professional Examination I at Defence Services Medical Academy, Yangon, Myanmar. The objectives of the study were to perform item analysis using Difficulty Index (DIF I) and Discrimination Index (DI) and to correlate between DIF I and DI.
Methods: A cross-sectional observational study was conducted with 200 multiple-choice questions from two written examination papers answered by 46 medical year 2 students of Defence Services Medical Academy, Yangon, Myanmar. Item analysis of multiple-choice questions were done by using DIF I and DI calculated post-exam.
Results: Results showed that the majority of items were categorized as easy based on DIF I, with 63% and 60% in Papers I and II, respectively. Only about one-third of items were deemed acceptable, and few fell into the difficult category. DI ranged from negative to excellent, with 62% and 61% of MCQs in Papers I and II showing acceptable to excellent discrimination. Items with poor discrimination (35% and 34% in Papers I and II) should be revised or discarded. Moreover, items with negative DI should be re-evaluated for potential key errors or vague wording. A low negative correlation between DIF I and DI was observed, indicating that as DIF I increased, discrimination power decreased. Notably, items with easy DIF I demonstrated a moderate negative correlation with DI, consistent with previous research.
Conclusions: This study underscores the importance of item analysis to enhance the validity of assessment tools and ensure the effective evaluation of student cognition levels. Consequently, reconstruction and modification of MCQs are recommended to improve assessment quality and accurately measure student abilities
The Effects of Wheat Types, Flour Quality Attributes and Processing Conditions on the Quality of Extruded Snack Foods
Established and supported under the Australian Government’s Cooperative Research Centre Progra
Water use efficiency of rainfed and paddy rice ecosystem : Disentangling agronomic and ecosystem water use of rice
Electronic Raman scattering in quantum dots revisited
We present theoretical results concerning inelastic light (Raman) scattering
from semiconductor quantum dots. The characteristics of each dot state (whether
it is a collective or single-particle excitation, its multipolarity, and its
spin) are determined independently of the Raman spectrum, in such a way that
common beliefs used for level assignments in experimental spectra can be
tested. We explore the usefulness of below band gap excitation and an external
magnetic field to identify charge and spin excited states of a collective or
single-particle nature.Comment: To appear in a special issue of Solid State Communications dedicated
to Eli Burstei
- …