three-legs type core

There are two kinds of ball cores: Cross ball core and three-ring type ball core.

球芯有两种: 十字型球芯和三环型球芯.

British social security system has gone through three stages: First, the "poor law" as the core of the relief-type social security system.

在这一社会背景下，英国社会保障制度经历了三个阶段：第一，以《济贫法》为核心的救济型社会保障制度阶段。

Same three-dimensional digital shot dynamometry system as size, weight and international standard shots for male and female putter was developed. The core was to force sensor of inside resistance strain type.

研制了外形、尺寸、重量与国际标准男、女铅球相同的三维数字测力铅球系统，其核心是内装电阻应变式三维力传感器。

Three softwares' comparison in seepage calculation and their application in analysis of core wall type rockfill dam constructed on deep overburden layer

三款软件在深覆盖层上心墙坝渗流分析中的应用