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SI单位制在连贯性,简便性,在区分质量和力,单位的选择和使用的统一性方面都优于以前的公制单位制。连贯性消除了该系统范围内不同于10的幂次方的换算因子。通过简化, 描述整个系统只需要7个基本单位,两个辅助单位,15个命名的导出单位和14个词冠。引入牛顿作为力的单位,而保留千克作为质量的单位,澄清了这两个量之间的差别。其它的新单位是表征压力的单位帕斯卡,表征电导的西门子和表征物质量值的摩尔。国际上一致同意尽量减少专门化单位的扩散或使用。已承认的规则包括每个单位的拼写法,缩写法,样式,使用方法,以及其定义。公差,数字的四舍五入,多位数中去掉逗号体现了新的意义。SI换算为减少许多产品的规格数目提供了独一无二的机会。为此目的已发展了用于公制标准化的一些设计。在将通用的单位换算成SI单位的过程中,其关键与其说是采用公制单位换算,倒不如说是“想要公制化”(“think metric”)。
The consistency and simplicity of the SI system is superior to the previous metric system in terms of the distinction between quality and force, the choice and use of units. Consistency eliminates the scaling factors in the system that are different from the power of ten. By simplifying, describing the entire system requires only seven basic units, two auxiliary units, 15 named export units and 14 word prefixes. The introduction of Newton as a unit of force, and the retention of kilograms as a unit of mass, clarified the difference between these two quantities. Other new units are Pascal, a unit that characterizes pressure, Siemens that characterize conductance, and Moore, which characterizes a substance. Internationally agreed to minimize the proliferation or use of specialized units. Admitted rules include the spelling, abbreviation, style, usage, and definition of each unit. Tolerances, numbers, rounding, multi-digit removal of commas reflects the new meaning. SI conversion offers a unique opportunity to reduce the number of specifications for many products. To this end, some designs for metric standardization have been developed. In converting common units to SI units, the key is not so much a metric unit conversion as “think metric”.