Overview of Major Research Themes

Research theme1_0

Facial Similarity Evaluation of Haniwa Figures

Issue: Haniwa classification often depends on subjective judgments based on shape and decorative observations, creating a need for objective and quantitative methods to support finer classification.

Method: Facial parts are automatically extracted from 3D point clouds and converted into depth images. Machine learning models then evaluate facial similarity from those depth images.

Result: The method enables numerical comparison of facial features and supports objective similarity evaluation.

Research theme1_1

Tumulus Distribution Prediction

Issue: Surveying undiscovered tumuli around widely distributed tumulus groups requires substantial labor, time, and cost.

Method: We focus on the relationship between UAV-LiDAR terrain point clouds and known tumulus distributions, and propose a deep learning method for estimating tumulus existence probability.

Result: The estimated probabilities are visualized as 2D heat maps and colorized 3D point clouds, allowing users to understand important terrain features and 3D terrain structure simultaneously.

Research theme1_2

Extraction of 3D Topological Maps of Stone Tools

Issue: Stone tool analysis is still largely manual and visual, which requires considerable time and effort.

Method: Using point cloud data from 3D measurement, we propose a method that jointly extracts edge features and junction regions.

Result: The method enables accurate evaluation of surface sharpness and efficient, low-cost feature extraction for similarity computation of stone tool shapes.

Research theme1_3

Image-Based Stone Tool Identification and Management Support

Issue: In the storage and management of excavated stone tools, human errors such as misidentification and bag mix-ups can occur.

Method: We use two stable-pose images defined for each stone tool and apply deep learning with CNNs and pretrained models.

Result: The approach achieved higher recognition accuracy and processing speed than previous work, and the high-performance model was implemented as a YOLO-based detector for practical use.

Research theme1_4

Reduction Simulation of Bone Fragments

Issue: In actual surgery, opportunities for trial and adjustment are limited, and aligning or visualizing bone fragments is difficult.

Method: Using measured point cloud data, the bone surface is separated into healthy and fracture surfaces, and bone fragments are automatically reconstructed by matching edge shapes.

Result: The simulation aims to improve preoperative planning efficiency and reduce trial and error during surgery.

Research theme1_5

Stone Tool Reassembly

Issue: The goal is to reassemble fragmented stone tools accurately and efficiently.

Method: We propose a flake-surface matching algorithm with an emphasis on computational efficiency.

Result: Experiments with 43 stone tool point cloud models demonstrated fast and accurate reassembly.

Research theme1

Hyperspectral Band Selection

Issue: Curse of dimensionality, data redundancy, high computational costs, and storage issues in hyperspectral imaging.

Method: Global Affinity Matrix Reconstruction.

Result: We proposed a method that identifies the most informative hyperspectral bands to enhance machine learning performance.

Research theme2

Feature Selection Validation

Issue: Curse of dimensionality, data redundancy, high computational costs.

Method: Compare clustering accuracy before and after applying feature selection.

Result: We verified that selecting the top 10% of representative features led to improved clustering accuracy.

Research theme3

Partial Shape Matching

Issue: How to estimate the internal 3D pose of the joining material?

Method: Divide-and-conquer strategy.

Result: We propose a method that performs partial shape matching between flake surfaces and joining material surfaces based on point cloud measurements, enabling more accurate alignment and fitting.

Research theme4

Component Reassembly Assistance

Issue: How to assist with component reassembly?

Method: Recording and replaying the disassembly sequence with simple marker detection.

Result: We propose a method to support component reassembly by guiding users through the recorded disassembly order, enabling faster and more accurate assembly.

Research theme5

Wine Cork Inspection

Issue: How to automate the inspection of wine corks for scratches or damage?

Method: Multi-scale Faster R-CNN.

Result: We propose a machine vision system to automatically detect the presence, severity, and type of scratches or damage on wine corks.

Research theme6

Center-Symmetrical Object Detection

Issue: How to detect center-symmetrical objects and identify their centers in arbitrary images?

Method: Gabor wavelet analysis.

Result: Our method accurately detects center-symmetrical objects and their central points.

Research theme7

Rat Sensing

Issue: How to analyze rat behavior using the optomotor response automatically?

Method: Contour line curvature analysis.

Result: We present a system that automatically extracts the rat’s head gaze orientation from each frame.

Research theme8

Real-time Profile Face Detection

Issue: How to speedup profile face detection?

Method: Dynamic image processing.

Result: We propose a method based on genetic algorithms.

Research theme9

Multiview Face Detection

Issue: How to detect various views of human face?

Method: Flipping Scheme.

Result: We propose a method to enhance the capability of frontal face detectors to detect multi-view faces.

Research theme9_3

Chicken Meat Quality Evaluation by Color

Issue: The objective is to evaluate color related to chicken meat freshness objectively, non-destructively, and without contact.

Method: We use smartphone images and a color card to perform automatic color correction and image analysis with a low-cost method.

Result: Hierarchical clustering of corrected color information showed that chicken meat quality can be classified into three levels.

Research theme9_2

Damage Detection in Pacific Saury

Issue: In packaging processes, external damage is inspected manually, which creates a heavy workload.

Method: The body region and head-tail direction are automatically determined, and a CNN is used to detect surface damage.

Result: A transfer learning model achieved 98.2% accuracy in damage classification.

Research theme10

Head-Tail Orientation Detection for Pacific Saury

Issue: Packaging processes require fish to be aligned with consistent head-tail orientation.

Method: Custom contour-rule-based head-tail judgment.

Result: We proposed body extraction and head-tail judgment methods that enable fast processing suitable for packaging pipelines.

Research theme11

Kabayaki Canned Food Production

Issue: Automation of a kabayaki canned food production line.

Method: Template matching.

Result: A simulation was developed to prioritize candidates with high fitness values and determine the grasping order for a robotic arm.

Research theme12

Line Filter Design

Issue: How to design a super-fast defect detector over flat surface?

Method: Custom line filter design.

Result: We propose a series of line filters tailored to detect defects on surfaces that are flat or exhibit directional flatness along the x-axis, y-axis, or diagonals.