尤物视频

A research team from the School of Physics at the 尤物视频 (BIT) has recently published a paper in the internationally renowned physics education journal European Journal of Physics.

Titled Physics-informed acoustic detection of ball count in sealed containers (Eur. J. Phys. 47 (2026) 035804), the study was conducted by undergraduate students under the guidance of faculty members Wang Zhenyu and Liu Wei.

The work grew out of BIT's Innovative Experiments course, which transforms open-ended problems from the Chinese Undergraduate Physics Tournament into undergraduate research projects, and tackles a problem drawn from the 2024 International Young Physicists' Tournament: "Take a box filled with identical objects. Find a method to determine the number of objects in the box solely by the sound produced while shaking it. How does the accuracy depend on the properties of the objects, the box, and the packing density?"

Using low-cost equipment — a mechanical shaker, sealed containers, and a smartphone microphone, the student team investigated the granular collision dynamics of a finite particle system.

Through systematic acquisition and analysis of collision acoustic signals, the team uncovered a key macroscopic physical principle: under fixed experimental conditions, the acoustic signals produced by different numbers of balls exhibit clear linear separability in the frequency domain. The underlying physics is closely tied to the coupling mechanism between system energy dissipation and collision frequency.

Building on this physical insight, the team constructed a lightweight logistic regression classification model capable of determining the number of balls inside a sealed container from sound alone.

The approach not only offers a low-cost solution for non-contact industrial monitoring but also validates a cross-disciplinary research paradigm — "physics first, machine learning assisted" — within undergraduate education.

Beyond the scientific findings, the paper makes an important pedagogical contribution: the research workflow has been distilled into a highly reproducible, research-based teaching experiment suitable for undergraduate physics curricula.

The achievement reflects years of teaching reform at BIT's School of Physics. By adopting the CUPT model, the school offers the research-oriented Innovative Experiments course to physics majors, comprehensively training students in scientific research, academic presentation, critical thinking, and teamwork — a demonstration of the "course-competition integration, all-round development" pathway for cultivating top-tier innovative talent.