Data fusion is the process of integrating multiple data sources to produce more consistent, accurate, and useful information than any single source can provide. With the advancement of data fusion technology, its application scope has expanded from traditional fields to geographic information systems (GIS) and has become an important tool for scientific exploration.
The data fusion process is usually classified as low, medium, or high level, depending on the processing stage at which the fusion occurs.
Low-level data fusion combines several raw data sources to generate new raw data. In this process, the fused data is expected to provide more informative results than the original input. For example, sensor fusion is a subset of data fusion, similar to the way humans and animals integrate information from multiple senses to improve survivability.
Obviously, the previous data fusion models can no longer meet the current complex information needs. In the mid-1980s, the Joint Laboratory Directors Group established a data fusion group. With the rise of the Internet, data fusion is not limited to the integration of sensor data, but also includes information fusion. The JDL/DFIG model divides different data processing processes into several levels in order to understand the effect of data fusion more clearly.
Although these models have certain application value in data fusion visualization and promote discussion and consensus, they are still criticized, especially in dealing with human-computer interaction.Currently, the Data Fusion Information Group (DFIG) model is divided into six levels: source preprocessing, object assessment, situation assessment, impact assessment, process refinement and user refinement.
In the field of GIS, data fusion is often synonymous with data integration. In these applications, it is very important to combine various diverse datasets into a unified dataset that contains all data points and time steps. A fused dataset is different from a simple collection because the fused data points have attributes and metadata that may not be included in the original dataset. For example, through data fusion, researchers can combine animal tracking data with marine habitat data to explore the interaction between animal behavior and environmental factors.
Off the coast of Tasmania, data fusion software was used to combine southern rock lobster tracking data with environmental data to create a four-dimensional image of rock lobster behavior.
Through this process, scientists are able to identify key locations and times in the environment and gain a deeper understanding of the ecosystem.
Outside of GIS, the concepts of data integration and data fusion are slightly different. In fields such as business intelligence, data integration is often used to describe the combination of data, while data fusion refers to the reduction or substitution that occurs after integration. Data integration can be viewed as the combination of sets, while fusion is a technique to improve efficiency.
In traffic sensing technology, data from different sensing technologies can be combined to accurately determine the traffic status. Data fusion methods using acoustic, image, and sensor data collected along the road have shown their effectiveness, leveraging the strengths of each individual method.
Also, in some cases, geographically distributed sensors are subject to power and bandwidth constraints. This results in raw data often being transmitted in just a few bits, and in this case, the decision fusion center is responsible for integrating the binary decisions sent by the sensors to improve classification performance.
In data fusion, new statistical methods such as Bayesian autoregressive Gaussian process and semi-parametric estimation have also been developed, which promotes the development of data fusion.
These methods make it possible to efficiently estimate results across multiple data sources, providing a more solid data foundation for scientific exploration.
In today's data-driven world, data fusion in GIS not only provides critical insights into the environment, but also drives further scientific discovery and understanding. Can we find new ways to solve future challenges in the continuous evolution of data fusion technology?