Vacuum packing preventing the evaporation of volatile components. It is also commonly used to store dry foods over a long period of time, such as cereals, nuts, cured meats, cheese, smoked fish, coffee, and potato chips (crisps). On a more short term basis, vacuum packing can also be used to store fresh foods, such as vegetables, meats, and liquids, because it inhibits bacterial growth. Vacuum packing greatly reduces the bulk of non-food items. For example, clothing and bedding can be stored in bags evacuated with a domestic vacuum cleaner or a dedicated vacuum sealer. This technique is sometimes used to compact household
Packing in a hypergraph at time formula_21. For a fixed broodtree, let formula_107 denote the probability that the branching process yields broodtree formula_57. Then the probability that History does not abort is formula_107. By the finiteness of the branching process, formula_110, the summation over all broodtrees formula_57 and History does not abort. The formula_112 distribution of its broodtree approaches the branching process distribution. Thus formula_60. In 1985, Rödl proved Paul Erdős’s conjecture by a method called the Rödl nibble. Rödl's result can be formulated in form of either packing or covering problem. For formula_114 the covering number denoted by formula_115 shows the minimal size