UML use case diagram - Trading system usage scenarios

"Algorithmic trading, also called automated trading, black-box trading, or algo trading, is the use of electronic platforms for entering trading orders with an algorithm which executes pre-programmed trading instructions whose variables may include timing, price, or quantity of the order, or in many cases initiating the order by a "robot", without human intervention. Algorithmic trading is widely used by investment banks, pension funds, mutual funds, and other buy-side (investor-driven) institutional traders, to divide large trades into several smaller trades to manage market impact and risk. Sell side traders, such as market makers and some hedge funds, provide liquidity to the market, generating and executing orders automatically.
A special class of algorithmic trading is "high-frequency trading" (HFT), which is often most profitable during periods of high market volatility. During the past years, companies such as Algorates have employed HFT strategies, recording high profits even during periods in which the markets have seen steep declines." [Algorithmic trading. Wikipedia]
The UML use case diagram example "Trading system usage scenarios" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Rapid UML solution from the Software Development area of ConceptDraw Solution Park.

"A document management system (DMS) is a computer system (or set of computer programs) used to track and store electronic documents. It is usually also capable of keeping track of the different versions modified by different users (history tracking). The term has some overlap with the concepts of content management systems. It is often viewed as a component of enterprise content management (ECM) systems and related to digital asset management, document imaging, workflow systems and records management systems. ...
Document management systems commonly provide storage, versioning, metadata, security, as well as indexing and retrieval capabilities." [Document management system. Wikipedia]
The block diagram example "Document management system architecture" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Block Diagrams solution from the area "What is a Diagram" of ConceptDraw Solution Park.