STGI：a spatio-temporal grid index model for marine big data

Figures & data

Figure 1. GeoSOT subdivision theory and grid code

Figure 2. The Z-order filling curve of GeoSOT grid code

Figure 3. Spatio-temporal grid index structure

Figure 4. Example of grid-level selection

Table 1. Metadata table structure

Spatial Code

Time Code

Marine Data Attribute 1

Marine Data Attribute 2

… …

Marine Data Attribute N

Table 2. Hardware environment configuration

Category	Environment
Processor	Intel Core i5-8259 U (4-core 2.3 GHz)
Memory	8GB
Hard Disk	256 G

Table 3. Software environment configuration

Category	Environment
Operation system	macOS Mojave
Development Tool	PyCharm
Development Language	Python, C
Database	MongoDB 4.0.3
Visualization Tool	Robo 3T 1.2

Table 4. Range query experiments in different time ranges (unit: ms)

	ObjectID	lat_lon_ height+time	lat+lon+ height+time	lat_lon_ height_time	Spatio-temporal Grid	STGI
1°×1°×10 (40rows)	13,487.2	3.2	3.3	2.5	1.2	1.1
1°×1°×30 (120rows)	14,455.2	3.4	3.7	3.1	1.9	1.1
1°×1°×50 (200rows)	14,638.3	3.4	3.9	4.3	2.3	1.3
2°×2°×10 (160rows)	16,719.7	5.9	6.6	6.4	3.2	2.3
2°×2°×30 (480rows)	13,209.8	6.6	7.4	10.5	5.5	3
2°×2°×50 (800rows)	17,221.4	7.6	8.1	14.3	10	3.6
3°×3°×10 (360rows)	15,976.4	10.9	10.3	10.9	6.5	3.8
3°×3°×30 (1080rows)	15,337.2	11	10.9	20.7	13.5	4.8
3°×3°×50 (1800rows)	18,041	12.7	13.5	31.4	23.2	6.4
4°×4°×10 (640rows)	16,774.2	14.9	13.9	18	12.3	4.9
4°×4°×30 (1920rows)	14,206.4	17.6	16.8	34.4	23.9	6.7
4°×4°×50 (3200rows)	17,380	21.6	19.2	52.9	40.2	8.8

Figure 5. STGI vs “lat_lon_height+time.”

Figure 6. STGI vs primary index model

Figure 7. Query time ratios of two index models

Figure 8. Comparisons of index models with different levels

Data availability statement

For the moment, the data from the project are not publicly available. The data that support the findings of this study will be available on request from the authors.