Journal of Information System Exploration and Research
Vol. 4 No. 4: October 2026

Efficient Pneumonia Detection with MobileNetV2 Through a Staged Optimization Pipeline and Grad-CAM Interpretability Evaluation

Faray Juan Tody (Department of Computer Science, Universitas Amikom Yogyakarta, Indonesia)
Majid Rahardi (Department of Computer Science, Universitas Amikom Yogyakarta, Indonesia)



Article Info

Publish Date
29 Oct 2026

Abstract

Pneumonia remains a major cause of morbidity and mortality, and chest X-ray screening in resource-constrained settings could benefit from lightweight deep learning models. This study provides an integrated evaluation of established techniques, adaptive histogram standardization (AHS), automatic mixed-precision (AMP) training, and FP16 post-training quantization, applied to a MobileNetV2-based pneumonia classifier, using a four-scenario ablation design with repeated hold-out validation across three seeds. The selected model of each scenario reached 91.03–91.42% test accuracy, and peak validation accuracy across seeds did not differ significantly between scenarios (p > 0.05, n = 3, which does not prove equivalence). AMP reduced training VRAM by 47.9%; FP16 quantization reduced model size by 49.6% and increased single-image throughput by 29.9% (1.30× speedup) over its FP32 counterpart, with a test confusion matrix identical to that of the autocast-evaluated FP32 model. False negatives decreased from 14 to 8 (42.9%) in the selected models. In three high-confidence true-positive cases, Grad-CAM maps remained qualitatively similar in location across all stages. In this dataset and configuration, staged optimization improved efficiency without measurable loss of accuracy; external validation and tests on physical edge devices are needed before deployment claims.

Copyrights © 2026






Journal Info

Abbrev

journal

Publisher

Subject

Description

Journal of Information System Exploration and Research is a journal that publishes and disseminates scientific research papers on information systems to a wide audience particularly within the information system ...