{"id":822,"date":"2012-10-07T22:23:35","date_gmt":"2012-10-08T02:23:35","guid":{"rendered":"http:\/\/www.reliabilityanalytics.com\/blog\/?p=822"},"modified":"2014-02-27T16:21:41","modified_gmt":"2014-02-27T20:21:41","slug":"discrete-event-simulation-tool-example-2","status":"publish","type":"post","link":"https:\/\/reliabilityanalytics.com\/blog\/2012\/10\/07\/discrete-event-simulation-tool-example-2\/","title":{"rendered":"Discrete Event Simulation Tool, Example 2, Comparison to MIL-HDBK-338"},"content":{"rendered":"

In this example, we use the\u00a0Discrete Event Simulation<\/a>\u00a0tool in the Reliability Analytics Toolkit to simulate system availability for a problem presented in MIL-HDBK-338, Reliability Design Handbook (page 10-42), as shown below.\"\"<\/a><\/p>\n

Based on the information provided in the above reliability block diagram (RBD), the MTBF and MTTR for the five subsystems is entered into input box #1, as highlighted below. The RBD indicates that all subsystems are critical; therefore, any failure will result in a critical failure. Therefore, we enter each subsystem, one per line, into input box #2. 20 trials of length 8,760 hours are simulated using a seed of 1. \u00a0Setting the seed allows the same results for the same inputs at a future time. \u00a0If the seed input is left blank, the system will randomly choose a starting seed and results will be similar from simulation-to-simulation, but not exactly the same.<\/p>\n

\"\"<\/a><\/p>\n

\"\"<\/a><\/p>\n

The picture below shows the simulated results for 20 trials. The simulated system availability is 73.58%, which compares well to the 0.73534 (73.534%) calculated above in MIL-HDBK-338B example.\"\"<\/a><\/p>\n

The underlying discrete event simulation engine is SimPy (Simulation in Python), which runs on the Google App Engine. See the references listed below for additional details on SimPy.<\/p>\n

References:<\/p>\n

    \n
  1. SimPy Home Page<\/a><\/li>\n
  2. Matloff, Norm, University of California at Davis, Dept. of Computer Science,\u00a0Introduction to Discrete-Event Simulation and the SimPy Language<\/a><\/li>\n
  3. Matloff, Norm, University of California at Davis, Dept. of Computer Science,\u00a0A Discrete-Event Simulation Course Based on the SimPy Language<\/a><\/li>\n
  4. Python pseudo-random number generator<\/a><\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

    In this example, we use the\u00a0Discrete Event Simulation\u00a0tool in the Reliability Analytics Toolkit to simulate system availability for a problem presented in MIL-HDBK-338, Reliability Design Handbook (page 10-42), as shown below.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[55],"tags":[12,68,58,42],"class_list":["post-822","post","type-post","status-publish","format-standard","hentry","category-system-modeling","tag-availability","tag-simulation","tag-system-modeling-2","tag-toolkit-examples"],"_links":{"self":[{"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/posts\/822","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/comments?post=822"}],"version-history":[{"count":20,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/posts\/822\/revisions"}],"predecessor-version":[{"id":859,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/posts\/822\/revisions\/859"}],"wp:attachment":[{"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/media?parent=822"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/categories?post=822"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/reliabilityanalytics.com\/blog\/wp-json\/wp\/v2\/tags?post=822"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}