The document describes a project to simulate an anti-collision system for trains using Erlang. Key aspects include: 1) The project uses Erlang processes and an in-memory cache to store train positions and status updates for fast access by the analyzer module. 2) The analyzer module uses a deadline monotonic algorithm to analyze train positions and schedules and determine if trains can run or if collisions may occur. 3) The simulation was tested with various scenarios and timing graphs, and the project successfully demonstrated real-time anti-collision detection and response.

1. Real Time System Project Anti Collision Railway System Simulation By Ankit Singh (935502) ‏ Mohammad Tarique Abdullah (935528)‏ University Of Applied Sciences, Frankfurt am Main

4. Introduction: Simple Architecture

6. Cache SET & GET operation: Tuple Description : {Train_Position, Priority, Direction, Track_Number, {{TNStartCP, TNEndCP, Misc}, Status, ElapsedTime, AvgTime}}} SET Method: traincache:set(“Train”,fraBer,{15,2, down, 1, { {40,60,8}, running, 0, 150 }}} )‏ GET Method: traincache:get(“Train”,fraBer)‏

9. Various Scenarios I

10. Various Scenarios II

11. Actual Screen shot of the project (a)‏

12. Actual Screen shot of the project (a)‏

13. Graph Distance against timing of trains (case 1)

14. Graph Distance against timing of trains (case 2)

16. Many companies are using Erlang in their production systems: • Amazon uses Erlang to implement SimpleDB, providing database services as a part of the Amazon Elastic Compute Cloud (EC2). • Yahoo ! uses it in its social bookmarking service, Delicious, which has more than 5 million users and 150 million bookmarked URLs. • Facebook uses Erlang to power the backend of its chat service, handling more than 100 million active users. • T-Mobile uses Erlang in its SMS and authentication systems. • Motorola is using Erlang in call processing products in the public-safety industry. • Ericsson uses Erlang in its support nodes, used in GPRS and 3G mobile networks worldwide.

17. The most popular open source Erlang applications include the following: • The 3D subdivision modeler Wings 3D, used to model and texture polygon meshes. • The Ejabberd system, which provides an Extensible Messaging and Presence Protocol (XMPP) based instant messaging (IM) application server. • The CouchDB “schema-less” document-oriented database, providing scalability across multicore and multiserver clusters.

18. • The MochiWeb library that provides support for building lightweight HTTP servers. It is used to power services such as MochiBot and MochiAds, which serve dynamically generated content to millions of viewers daily. • RabbitMQ , an AMQP messaging protocol implementation. AMQP is an emerging standard for high-performance enterprise messaging.

19. Conclusion -We successfully implemented in-memory centralised caching system which can be used by any other modules by simple 'set' & 'get' operation. -Analyser/scheduler can make decision on run time on accessing the Train's data from cache. -We succesfully implemented Real Time System Project for Simulation of 'anti collision railways System'.