The Brick schema represents building equipment, sensors, spaces, and the relationships between them as typed, multi-relational graphs, providing machine-readable metadata that supports generalizable control applications. Current methods for producing complete Brick models require extensive manual examination of building schematics and point lists. We observe that as Brick models are knowledge graphs, inferring missing relations is naturally posed as a knowledge graph completion problem. To the best of our knowledge, this is the first application of knowledge graph completion to Brick model generation. We compare three methods, gradient-boosted trees, Pairwise Brick Relation Ranking, and CompGCN, on the relations feeds, hasPart, and hasPoint, which account for the majority of the schematic-reading work in building a Brick model by hand. Models are evaluated on held-out MORTAR buildings and out-of-distribution Kaggle and Building Time Series data. Although CompGCN is the strongest performer on held-out buildings under metrics resistant to class imbalance, leading macro-F1 and AUPRC, no method generalizes uniformly across datasets or relations.
Figures & tables
Figure 1: A two-hop Brick graph fragment. Our completion targets are the typed, directed relations feeds , hasPart , and hasPoint .
Figure 2: Brick represents building entities and their relationships as a typed graph ( 2(a) ); our task is to recover missing target edges ( 2(b) ).
Dataset summary
Target relations
Dataset
Buildings
Entities
Triples
Rel. types
Test edges
feeds
hasPart
hasPoint
MORTAR
45
19,388
69,159
7
755
4,650 (21%)
4,891 (22%)
12,646 (57%)
Kaggle
6
23,578
86,493
12
15,507
4,639 (12%)
3,402 (9%)
30,734 (79%)
BTS
1
1,115
4,253
9
534
189 (14%)
253 (19%)
894 (67%)
Table 1: Dataset statistics and target-relation distributions after normalization. Relation entries report counts with row-wise percentages in parentheses.
Dataset
Model
Link F1
Macro-F1
Micro-F1
AUPRC
MORTAR
Random
0.208±0.001
0.068±0.002
0.070±0.002
0.115±0.003
Type-pair
0.255
0.262
0.255
0.230
GBT
0.413±0.043
0.485±0.050
0.413±0.043
0.472±0.008
PBRR
0.824±0.044
0.739±0.021
0.824±0.044
0.815±0.018
CompGCN
0.810±0.031
0.746±0.022
0.810±0.031
0.916±0.007
Kaggle
Random
0.183±0.001
0.056±0.001
0.061±0.001
0.102±0.000
Table 2: Aggregate link-existence and relation-classification performance across MORTAR, Kaggle, and BTS. Values are mean ± standard deviation. Best results per dataset are bold.
MORTAR
Kaggle
BTS
Model
hasPoint
hasPart
feeds
hasPoint
hasPart
feeds
hasPoint
hasPart
feeds
Random
0.107
0.046
0.052
0.129
0.017
0.023
0.124
0.041
0.030
Type-pair
0.257
0.310
0.219
0.148
0.178
0.154
0.173
0.234
0.109
GBT
0.282
0.652
0.521
0.131
0.158
0.186
0.743
0.000
0.009
PBRR
0.927
0.658
0.633
0.000
0.013
0.002
0.000
0.126
0.067
CompGCN
0.944
0.668
0.624
0.342
0.062
0.116
0.159
0.070
0.016
Table 3: End-to-end F1 for each target relation across datasets. Values are means across seeds; best results per dataset and relation are bold.
Knowledge graph construction turns text, tables, images, and databases into structured entities and relationships that machines can query and reason over.
We train a language model to generate LEGO-brick build sequences. While prior work has been restricted to discrete, voxel-like towers, we consider a much broader set of pieces, encompassing thousands of part types with diverse connection semantics. To enable this, we first collect a large-scale dataset of over 100,000 human-designed LDraw brick objects and scenes. The complexity of our setting makes it challenging to autoregressively assemble structures that satisfy physical constraints. When predicting block pose directly, build sequences quickly become invalid after a small number of steps. Although pieces are placed in 3D space, it is the spatial relationships of the parts which define the whole. With this in mind, we design a graph-based program representation that parametrizes structure through connectivity, improving the physical grounding of generated sequences. To enable future applications, we make our dataset and models available for research purposes. https://kulits.github.io/BrickNet
Peter Kulits, Cordelia Schmid
Inria, `Ecole Normale Sup`erieure, CNRS, PSL Research University · Max Planck Institute for Intelligent Systems, Tübingen
Building Management Systems (BMS) are essential for optimizing energy efficiency and operational performance in modern buildings. However, the lack of standardization across BMS points from different manufacturers creates significant barriers to integration and data utilization. While the Brick schema offers a standardized ontology for building systems, mapping BMS points to appropriate Brick classes presents three critical challenges: (i) the extensive number of Brick classes (936 in the latest version), (ii) limited domain-specific knowledge in large language models (LLMs), and (iii) substantial manual effort required for verification. To address these challenges, we propose Brick-DICL, a two-stage dynamic in-context learning framework for automated Brick schema classification. Brick-DICL consists of two primary components: metadata-RAG, which retrieves relevant examples to enhance LLMs' domain knowledge, and class-RAG, which narrows down potential Brick classes to address the large classification space. Additionally, we implement a multi-LLM filtering mechanism that compares predictions across multiple models, flagging low-confidence classifications for human review. As a result: (i) General: Brick-DICL is applicable to any building management system regardless of manufacturer or metadata format; (ii) Novel and Powerful: as the first dynamic in-context learning approach for Brick schema classification, Brick-DICL achieves significant classification accuracy improvements on building datasets, outperforming existing methods; (iii) Efficient: our multi-LLM filtering strategy reduces manual verification effort, enabling rapid digital building onboarding. Extensive experiments demonstrate Brick-DICL's effectiveness across diverse building datasets, accelerating the path toward standardized, interoperable building management systems.
Knowledge graphs (KGs) organize real-world knowledge as triplets and underpin many downstream applications. Due to their inherent incompleteness, knowledge graph completion (KGC) is widely studied and is typically formulated as triplet prediction, with link prediction as the dominant paradigm. However, this formulation focuses on the incompleteness of triplet-wise information and overlooks the incompleteness of entity-relation compatibility information. To address this limitation, we introduce a relation set completion task (RSC), which complements the link prediction task and aims to reason about missing relations that are semantically compatible with a given entity. We further propose a Relation Set Embedding model (RelSetE), which models latent patterns among the observed relations of entities to infer missing ones. To evaluate RelSetE, we derive three benchmark datasets from standard KG benchmarks. Extensive experiments demonstrate that RelSetE effectively captures entity-relation compatibility patterns and performs favorably in inferring missing relations of entities. Code and data are publicly available.
Zihao Zheng, Borui Cai, Yao Zhao +2
School of Information Technology, Deakin University, VIC 3125, Australia · Hangzhou International Innovation Institute, Beihang University, Hangzhou 311115, China · School of Information Technology, Victoria University, VIC 3011, Australia +1