Relational databases can represent nested data structures by using structured types or tables with foreign keys but it is difficult to search these structures for objects at an unknown depth of nesting 关系数据库可以通过使用结构化类型或带有外键的表，表示嵌套数据结构，但要为不知道其嵌套深度的对象搜索该结构是很困难的。
Another common tool used by the epd is the wilcoxon - mann - whitney test , which tracks significant differences in two sets of comparable data . this test is particularly useful for examining year - to - year changes in water monitoring results 另一种常用的统计分析方法是wilcoxon - mann - whitney测试，主要用于比较两套数据间的差异，特别对测试水质的年与年之间的变化尤其有用。
Then , constructing two sets of datum flows for structural analyses and structural optimization iterations , respectively , and a mapping method between them , a software dealing with three - dimension mechanical structural topology optimizations was presented 然后，构建分别用于结构分析和结构优化迭代的两套数据流和它们间的映射方法，研究和开发三维机械结构拓扑优化设计软件。
The assembly language program collects and processes the data real time . comparing kinds of method of filter and arithmetic of fft , the author select the fir filter to realize pretreatment of signal and radix - 2 fft to distill the characters of librations 通过对各种滤波方法和fft算法进行比较，本套数据检测和校准处理系统采用fir滤波对采集到的信号进行预处理，利用基2fft算法来提取信号的频率特征。
They can be purchased through apple ' s itunes store , for prices ranging from . 95 for a single book to 9 for the whole series , which , according to random house , includes a " full color digital booklet " and " previously unreleased readings " by rowling 这套数字有声读物由罗琳现在的音像出版商兰登书屋音像出版集团公司出版发行，可以在apple ' s itunes商店购买，单本书售价32 . 95美元，整套书的价格为249美元。
They can be purchased through apple ' s itunes store , for prices ranging from 32 . 95 for a single book to 249 for the whole series , which , according to random house , includes a " full color digital booklet " and " previously unreleased readings " by rowling 这套数字有声读物由罗琳现在的音像出版商兰登书屋音像出版集团公司出版发行，可以在apple ' s itunes商店购买，单本书售价32 . 95美元，整套书的价格为249美元。
Right afterwards , mr . iwasaki from sharp corporation then introduced their new dvd recorder that can " simultaneously record 2 digital terrestrial broadcast programs , " along with the demonstration of their realized superior feature qualities of " aquos familink . 夏普株式会社的岩崎先生就录像机新产品作了讲解，他介绍了目前已经在产品“ aquos familing ”中实现了的， ”同时将2套数字播放节目进行录像”的优越性能。
By comparing the data collection and processing system based on tms320c30 and the system based on conventional cpu , the author find the running time of the former is much shorter than the latter . so the system can satisfy real time better than the old one 通过对基于tms320c30的数据采集及处理系统和基于传统的cpu的数据采集及处理系统进行比较，发现前者的系统运行时间要远远少于后者的运行时间，因此本套数据检测和处理系统能够满足实时性的要求。
Only few analog tv channels are there in country areas and what more the covering range of the analog transmitters is smaller than that of digital transmitters which though with the same power , which result in that the covering site of broadcasting signals is always the urban areas while people who live in the remote areas receive no tv program signals , and as the essential parts of utilities for our party and governments to expressing its administration conception , broadcasting in suburban areas by far cannot give the government the ability to give publicity to the people effectively 农村广播电视的覆盖工作,长期以来一直是我们广播事业建设的薄弱环节。模拟电视节目套数很少,而且同等功率的模拟发射机覆盖范围也相对数字发射机的小,通常只是集中覆盖主要城镇和人口聚集地,偏远地区的广大群众长期不能收看电视。广播电视作为党和政府喉舌的功能,没有得以充分发挥。
Huari brake co . , having been experienced hard work and progression for 10 years , has formed a powerful strength and technical experience on the production scale and product development , now , it holds 300 odd - workers and more than 60 administrators of various high grade specialties , two automatic production lines , over 260 sets of the production equipments , several advanced detecting facilities and a skillful group on the research of science . the annual capacity of our company 华日公司经过十多年的努力与发展，在生产规模和产品开发中已积累了雄厚的实力和技术经验，公司现有职工300余人，各类高级专业管理人员40余人，公司拥有二条自动生产流水线生产设备260余套数台先进检测设备和一支精锐的科研队伍。
