--- abstract: 'We present here a case study developing a parallel program. The approach that we use combines refinement and decomposition techniques. This involves in the first step to abstractly specify the aim of the program, then subsequently introduce shared information between sub-processes via refinement. Afterwards, decomposition is applied to separate the resulting model into sub-models for different processes. These sub-models are later independently developed using refinement. Our approach aids the understanding of parallel programs and reduces the complexity in their proofs of correctness.' accompaniment: [] book_title: ~ commentary: ~ completion_time: ~ composition_type: ~ conductors_id: [] conductors_name: [] contact_email: ~ copyright_holders: [] corp_creators: [] creators_id: - htson@inf.ethz.ch - jabrial@inf.ethz.ch creators_name: - family: Hoang given: Thai Son honourific: '' lineage: '' - family: Abrial given: Jean-Raymond honourific: '' lineage: '' data_type: ~ date: 2010-02 date_type: published datestamp: 2010-02-05 10:39:21 department: ~ dir: disk0/00/00/02/06 divisions: [] edit_lock_since: ~ edit_lock_until: ~ edit_lock_user: ~ editors_id: [] editors_name: [] eprint_status: archive eprintid: 206 event_dates: ~ event_location: ~ event_title: ABZ2010 event_type: conference exhibitors_id: [] exhibitors_name: [] fileinfo: '' full_text_status: none funders: [] id_number: ~ importid: ~ institution: ~ isbn: ~ ispublished: inpress issn: ~ item_issues_comment: [] item_issues_count: 0 item_issues_description: [] item_issues_id: [] item_issues_reported_by: [] item_issues_resolved_by: [] item_issues_status: [] item_issues_timestamp: [] item_issues_type: [] keywords: ~ lastmod: 2010-02-05 10:39:21 latitude: ~ learning_level: ~ longitude: ~ lyricists_id: [] lyricists_name: [] metadata_visibility: show monograph_type: ~ note: ~ num_pieces: ~ number: ~ official_url: ~ output_media: ~ pagerange: ~ pages: ~ patent_applicant: ~ pedagogic_type: ~ place_of_pub: ~ pres_type: paper producers_id: [] producers_name: [] projects: [] publication: ~ publisher: ~ refereed: TRUE referencetext: ~ related_url_type: [] related_url_url: [] relation_type: [] relation_uri: [] rev_number: 6 series: ~ skill_areas: [] source: ~ status_changed: 2010-02-05 10:39:21 subjects: - deploy_method_comp succeeds: ~ suggestions: ~ sword_depositor: ~ sword_slug: ~ task_purpose: ~ thesis_type: ~ title: Event-B Decomposition for Parallel Programs type: conference_item userid: 16 volume: ~