The term "transformer" can refer to different concepts depending on the context. Here are the main uses:
### 1. **Electrical Transformer**
An electrical transformer is a device used to change the voltage of alternating current (AC) in a circuit. It operates on the principle of electromagnetic induction and consists of two or more coils (or windings) wrapped around a core. Here's how it works:
- **Primary Winding**: The coil that receives the input voltage.
- **Secondary Winding**: The coil that delivers the transformed voltage.
- **Core**: Usually made of iron or steel, it helps to channel the magnetic flux between the windings.
When AC voltage is applied to the primary winding, it creates a magnetic field that induces a voltage in the secondary winding. The voltage can be increased or decreased depending on the number of turns in the primary and secondary coils. This is crucial for transmitting electricity efficiently over long distances and for providing the correct voltage for various electrical devices.
### 2. **Transformer in Machine Learning (AI)**
In the context of machine learning, particularly natural language processing (NLP), a Transformer is a type of model architecture introduced in the paper "Attention is All You Need" by Vaswani et al. in 2017. Unlike previous models that relied heavily on sequential processing (like RNNs or LSTMs), Transformers use a mechanism called "attention" to process data in parallel, which significantly improves performance and efficiency.
Here’s a brief overview of how it works:
- **Attention Mechanism**: Instead of processing data sequentially, the Transformer uses self-attention to weigh the importance of different parts of the input data. This allows the model to focus on relevant pieces of information and handle long-range dependencies better.
- **Encoder and Decoder**: The Transformer architecture is divided into an encoder and a decoder. The encoder processes the input data and generates a set of representations, while the decoder uses these representations to produce the output. In tasks like translation, the encoder converts the input text into an internal representation, and the decoder generates the translated text.
- **Positional Encoding**: Since Transformers don’t process data sequentially, they use positional encoding to maintain the order of words or elements in the input.
Transformers have revolutionized NLP by improving the performance of various models, including BERT, GPT, and T5, and are also being adapted for other tasks beyond language, such as image processing.
### Summary
- **Electrical Transformer**: A device that changes voltage levels in AC circuits using electromagnetic induction.
- **Machine Learning Transformer**: An architecture that processes data in parallel using self-attention mechanisms to improve efficiency and performance in tasks like language modeling.
Both types of transformers have had significant impacts in their respective fields, one in electrical engineering and the other in artificial intelligence.