Waveform Similarity Calculation via Axis Shifting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for extracting similar waveforms from historical data are labor-intensive and prone to misalignment errors, leading to undervaluation of similar waveforms due to absolute value misalignment and scaling differences.

Innovation Solution

A data similarity calculation method that involves converting time series data into two-dimensional coordinates, shifting and scaling the waveforms to maximize similarity by adjusting both the time and value axes, and extracting the optimal shift and scaling parameters to align and match waveforms accurately.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If waveform similarity is calculated using absolute value alignment, then calculation speed is improved, but measurement precision deteriorates due to misalignment errors

Engineering Contradiction:
Improvecalculation speedVSAvoidsimilarity calculation accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent transforms the one-dimensional time series data into two-dimensional coordinate space, where the x-axis represents time and the y-axis represents the value axis. This dimensional transformation enables independent adjustment of time-axis shift and value-axis shift, allowing the system to simultaneously optimize both alignment accuracy and calculation efficiency by operating in a higher-dimensional parameter space.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent introduces two independent parameters: time-axis shift amount and value-axis shift amount. By changing these parameters systematically, the patent enables flexible adjustment of waveform alignment without requiring complex manual intervention. The dual-parameter approach allows the system to explore different alignment configurations efficiently while maintaining high measurement precision.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If manual searching of historical data is performed, then measurement precision is improved, but loss of time increases significantly

Engineering Contradiction:
Improvewaveform matching accuracyVSAvoidsearch time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent enables the system to automatically perform waveform alignment and similarity calculation without requiring manual intervention. The computer automatically adjusts time-axis and value-axis shift parameters, calculates similarities, and identifies matching waveforms. This self-service capability eliminates the time-consuming manual search process while maintaining high accuracy through systematic parameter exploration.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If waveform alignment requires precise manual adjustment, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvealignment accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent separates the alignment process into two independent adjustment components: time-axis shift and value-axis shift. This segmentation allows each parameter to be adjusted independently through simple additive operations, avoiding the need for complex coupled adjustment mechanisms. The decomposition of the alignment problem into independent dimensional adjustments significantly reduces system complexity while maintaining high alignment precision.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentUS9189198B2Data similarity calculation method and data similarity calculation apparatus
Publication Date: 2015.11.17 YOKOGAWA ELECTRIC CORP
  • US9189198B2 patent drawing
  • US9189198B2 patent drawing
  • US9189198B2 patent drawing

AI summary

There is provided a data similarity calculation method. The method includes: (a) acquiring a first waveform; (b) storing time series data; (c) converting the stored time series data into a waveform on two-dimensional coordinates, wherein the two-dimensional coordinates consists of a time axis and an a value axis representing values of the time series data, and the time axis is orthogonal to the value axis; (d) shifting the converted waveform in both directions of the time axis and the value axis so as to generate a second waveform; (e) calculating a similarity between the first waveform and the second waveform; and (f) extracting a shift amount in the direction of the time axis and a shift amount in the direction of the value axis when the similarity is the highest by repeatedly performing steps (d) and (e).