食用菌育种

历史追溯法

阴疮的治疗原则，应按热者______、寒者______、湿者______、坚者______。虚者______、下陷者______的原则处理。常采用______合治的方法。

串级控制系统能使等效副对象的时间常数（），放大系数（），因而使系统的工作频率提高。

如图所示，一束平行光从真空射向一块半圆形的折射率为1.5的玻璃砖，正确的是(       )

A．只有圆心两侧范围外的光线能通过玻璃砖

B．只有圆心两侧范围内的光线能通过玻璃砖

C．通过圆心的光线将沿直线穿出不发生偏折

D．圆心两侧范围外的光线将在曲面上产生全反射

Across a wide variety of fields, data are being collected and accumulated at a dramatic pace. There is an urgent need for a new generation of computational theories and tools to assist humans in (96) useful information (knowledge) from the rapidly growing (97) of digital data. These theories and tools are the subject of the emerging field of knowledge discovery in database (KDD). At an abstract level, the KDD field is concerned with the development of methods and techniques for making (98) of data. The basic problem addressed by the KDD process is one of mapping low-level data(which are typically too voluminous to understand and digest easily) into other forms that might be more (99) (for example, a short report), more (100) (for example, a descriptive approximation or model of the process that generated the data), or more useful (for example, a predictive model for estimating the value of future cases). At the core of the process is the application of specific data-mining methods for pattern discovery and extraction.

（99）是（）

A.dense

B.compact

C.extensile

D.short