An ordinary Petri net is a bipartite directed graph composedof places, drawn as circles, and transitions, drawn as bars. A formal denitionfollows [3]:Denition 2.1 An ordinary Petri Net (PN) is a 5-tuplePN = (P;T;I ;I + ;M 0) where:1. P = fp 1 ;p 2 ;:::;p n gis a nite and non-empty set of places,2.
The Colors of Geraniums. Geraniums come in a host of colors, from the traditional white, red and pink to the more exotic orange and purple. Geraniums (Pelargonium spp.) are popular garden favorites that can be cultivated throughout all the USDA hardiness zones as annuals or year-round as indoor plants.
Sow seed geraniums in well-drained soil with a pH of 6.0 to 6.2. The seeds do not need light to germinate, but a thin layer of vermiculite helps retain moisture. Seed geraniums also benefit from light fertilization one to three days after sowing. Sow seeds indoors about eight to 10 weeks before moving them outdoors with other warm-weather annuals.