Fabrication of a Nanosize Hematite Pigment via Waste Ferrous Sulfate Recycling Using Sulfur Reduction

Nanometer-sized hematite was prepared via a two-step process. In the first step, FeSO₄·7H₂O was oxidized to Fe₂(SO₄)₃ by oxygen in an acidic solution. In the second step, the Fe₂(SO₄)₃ was reduced to nanosize hematite with sulfur vapor at 550 °C. The...

A Looseness Detection Method for Railway Catenary Fasteners based on Reinforcement Learning Refined Localization

Brace sleeve (BS) fasteners, i.e., nut and bolt, are small components but play essential roles in fixing BS and cantilever in railway catenary system. They are commonly inspected by onboard cameras using computer vision to ensure the safety of railway operation. However, most BS fasteners cannot be directly localized because they are too...

A rapid and high-precision mountain vertex extraction method based on hotspot analysis clustering and improved eight-connected extraction algorithms for digital elevation models

Digital Elevation Model (DEM)-based mountain vertex extraction is one of the most useful DEM applications, providing important information to properly characterize topographic features. Current vertex-extraction techniques have considerable limitations, such as yielding low-accuracy results and generating false mountain vertices. To overcome...

Action-driven Reinforcement Learning for Improving Localization of Brace Sleeve in Railway Catenary

Brace Sleeve (BS) plays an essential role in connecting and fixing cantilevers of railway catenary systems. It needs to be monitored to ensure the safety of railway operations. In the literature, image processing techniques that can localize BSs from inspection images are proposed. However, the boxes produced by existing methods can contain...

Voxel-Based Extraction and Classification of 3-D Pole-Like Objects From Mobile LiDAR Point Cloud Data

The digital mapping of road environment is an important task for road infrastructure inventory and urban planning. Automatic extraction and classification of pole-like objects can remarkably reduce mapping cost and enhance work efficiency. Therefore, this paper proposes a voxel-based method that automatically extracts and classifies three...