Knowledge Base Retrieval and Recall for Construction

What Data for This Category Looks Like

Data for this category mainly comes from official manufacturer product manuals, technical parameter documents, marketing promotional materials, and after-sales maintenance guides. Update frequency aligns with new product launches, regional promotional policy adjustments, and working condition adaptation plan updates. Most documents are structured by machine model, with parameter entries including rated power, working radius, and dead weight. They also include real photos, working condition diagrams, and application scenario descriptions. Fields contain clear physical units such as kW, m, and t, plus exclusive identifiers like model numbers and applicable working condition tags.

What Constraints Do These Characteristics Impose on Knowledge Base Retrieval and Recall?

Construction machinery data characteristics create multiple constraints for retrieval and recall workflows. Documents are typically long and densely packed with parameters. Text segments must be split reasonably to retain parameter associations and avoid splitting critical information during retrieval. Fields and units require high precision. Recall results must match exclusive parameters for specific machine models, with no unit confusion or parameter misalignment. Marketing materials and technical documents update at inconsistent frequencies. Incremental updates must be supported to reduce resource costs from full synchronization. Most documents include high-definition parameter diagrams and working condition diagrams. Image parsing functionality must be enabled to extract text from images and avoid missing key marketing content.

How to Set Configurations

Configuration Item	Recommended Value	Rationale
`chunkSize`	`800–1200 characters`	Construction machinery documents are densely packed with parameters. Segments must retain parameter group integrity to avoid splitting associated information
`similarity threshold`	`0.72–0.80`	Marketing content requires precise matching of machine model parameters and application scenarios. This prevents low-relevance materials from being recalled
`maximum number of knowledge base references`	`Top 6–10 entries`	There are many marketing materials and technical documents for the same machine model. Too many references will increase context redundancy
`PARSE_IMAGE_ENABLE`	`Enabled`	Most construction machinery documents include parameter tables, product photos, and working condition diagrams. Image text must be parsed
`maxContext`	`8000–12000 characters`	Accommodate complete machine model parameter documents and associated marketing materials. Supports long-context retrieval
`UPLOAD_FILE_MAX_SIZE`	`500 MB`	Supports upload of large product manuals containing high-definition drawings

The parameter values provided on this page are common recommended starting points for configuration. Actual values are affected by material format, data volume, and business rules. Specific issues require targeted analysis, and it is recommended to test against your own samples before finalizing settings.

Three Common Mistakes

After uploading a docx-format product manual, the image area displays as empty or contains no text. This happens because the PARSE_DOCX_IMAGE configuration item is not enabled, and in-document image parsing is not turned on.
Retrieval results include large amounts of irrelevant general machinery content, with recalled entries exceeding the configured limit. This happens because the similarity threshold is not set, or is set too low, allowing low-relevance materials to be recalled.
Knowledge base loading times out in a local deployment environment, with the 504 Gateway Timeout error returned. This happens because the PARSE_FILE_TIMEOUT_SECONDS configuration is not adjusted. The default timeout period is insufficient to parse large construction machinery drawing documents.

How to Confirm Configurations Are Correctly Applied

Upload a docx product manual that includes parameter diagrams. Verify that parsed text includes parameters such as rated power and working radius from within images, to confirm the image parsing configuration is active.
Enter the test query "Rated power of a certain excavator model". Check that the number of returned recall results matches the configured maximum number of knowledge base references, to confirm the recall rule is active.
Adjust the similarity threshold, then re-enter the same query. Compare changes in the relevance of recall results to confirm the threshold configuration is active.
Upload a large product manual under 500 MB. Confirm the upload and parsing processes complete without timeout errors, to confirm the file size configuration is active.

Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-14.