“sign”的概念、定义、翻译、参考文献-科学参考

sign

Mathematics

A symbol denoting an operation, such as+, −, × and ÷ in arithmetic or ∘ to denote composition of functions, etc. The positive or negative nature of a quantity is called its sign.

Computer

A means used to distinguish between positive and negative numbers. In a computer there are a number of ways of representing the sign of a number, each of which makes use of a single bit called the sign bit. The most obvious way of representing positive and negative integers in computer words is by means of the signed-magnitude (or sign-and-magnitude) representation. Here, the leftmost bit in a word is used to denote the sign (0 for + and 1 for −) and the remaining bits in the word are used to represent the magnitude of the integer. It is more usual, however, for a computer to use the two’s complement representation of integers. See complement number system, radix complement.

Logic

In some approaches to proof theory, an element of syntax appended to a formula that acts as a counterpart to some semantic property, e.g., a truth value or a possible world. A formula that has a sign is a signed formula. The device permits the importation of nuanced semantic properties into a proof calculus, e.g., a semantic truth condition such as
- • if $φ$ takes value $v_{0}$ and $ψ$ takes value $v_{1}$ , then the formula $φ \land ψ$ take value $v_{2}$
can be given a proof-theoretic account by a corresponding rule
- • from $v_{0} : φ$ and $v_{1} : ψ$ , infer $v_{2} : φ \land ψ$
where each $v$ denotes a syntactic sign associated with truth value $v$ .

单词	sign
释义	sign Mathematics A symbol denoting an operation, such as+, −, × and ÷ in arithmetic or ∘ to denote composition of functions, etc. The positive or negative nature of a quantity is called its sign. Computer A means used to distinguish between positive and negative numbers. In a computer there are a number of ways of representing the sign of a number, each of which makes use of a single bit called the sign bit. The most obvious way of representing positive and negative integers in computer words is by means of the signed-magnitude (or sign-and-magnitude) representation. Here, the leftmost bit in a word is used to denote the sign (0 for + and 1 for −) and the remaining bits in the word are used to represent the magnitude of the integer. It is more usual, however, for a computer to use the two’s complement representation of integers. See complement number system, radix complement. Logic In some approaches to proof theory, an element of syntax appended to a formula that acts as a counterpart to some semantic property, e.g., a truth value or a possible world. A formula that has a sign is a signed formula. The device permits the importation of nuanced semantic properties into a proof calculus, e.g., a semantic truth condition such as • if $φ$ takes value $v_{0}$ and $ψ$ takes value $v_{1}$ , then the formula $φ \land ψ$ take value $v_{2}$ can be given a proof-theoretic account by a corresponding rule • from $v_{0} : φ$ and $v_{1} : ψ$ , infer $v_{2} : φ \land ψ$ where each $v$ denotes a syntactic sign associated with truth value $v$ .
随便看	EXAFS examination paradox example ex ante exaptation exa‐ exbi- excavates excavation Excel excentre exception exception handling excess-3 code excess air excess burden excess capacity excess demand excess electron excess factor excess flow valve excess-n notation excess profit excess reactants exchange