This paper is on fuzzy decision theory and information security theory which are mutually independent and engrafted. This paper presents both-branch fuzzy decision and problems on decision encryption-authentication, puts forward two kinds of both-branch fuzzy decision on X: both-branch fuzzy decision on X having bounded domains X = X+∩X- ={x0}, both-branch fuzzy decision on X havingoverlapping domains X* = X+∩X- = {x_1~*,x_2~*,…,x_1~*}. It presents single branch separate-separate out theoremof both-branch fuzzy decision on X, single branch superposition theorem of both-branch fuzzy decision, exclusive-decompose principle of both-branch fuzzy decision. This paper presents encryption-authentication theorem of decision by engrafting information security theory and technique with both-branch fuzzy decision, and provides encryption-decryption and signature-authentication of both-branch fuzzy decision.
S-粗集(singular rough sets)具有两类形式:单向S-粗集(one direction S-rough sets)和双向S-粗集(two direction S-rough sets)。S-粗集具有遗传特征、记忆特征。把S-粗集与材料科学进行学科渗透,互补共享,给出新金属材料的发现-识别的讨论,利用属性生成模型给出新金属材料的属性值分析,给出的结果与实际相符。S-粗集是粗集研究的一个新方向,是新材料发现-识别的一个新的数学工具。