非正弦不对称三相三线电路负载侧相电压的定义与测量

对非正弦不对称三相三线电路，如何恰当地定义负载侧的相电压并能方便地测量一直未有明确的统一认识。本文从研究三相三线电路中相电压与线电压的关系着手，根据外部等效的思想。来定义三相三线电路负载侧的相电压。按此定义的相电压恒满足ｕ，＋“ｂ＋“ｃ＝０，并可方便地通过三相电压互感器或直接依据负载侧的线电压来唯一确定负载侧的相电压。     

触变泥浆润滑套在沉井工程中的应用

论述触变泥浆润滑套在沉井工程中的应用及主要参数。     

LF半准开集的一种新定义

给出了一种新的ＬＦ半准开集定义，采用新的ＬＦ半准开集定义，较详细地研究了ＬＦ半准开集及半准连续函数的一些重要性质。     

A fuzzy constraint satisfaction approach for electronic shopping assistance

The Internet and World Wide Web offer an additional channel for consumers to find, select, and buy products. However, unlike shopping in the traditional store, consumers have no direct contact with human clerks to get the required information in the electronic store. The objective of this paper is to propose a fuzzy constraint satisfaction approach to help buyers find fully satisfactory or replacement products in electronic shopping. For the buyer who can give precise product requirements, the proposed approach can generate product-ranking lists based on the satisfaction degrees of each product to the given requirements. For the buyer who may not input accurate requirements, a similarity analysis approach is proposed to assess buyer requirements automatically during his browsing process. The proposed approach could help buyers find the preferred products on the top of the ranking list without further searching the remaining pages. The experimental results show the applicability of the proposed approach for electronic shopping assistance.     

Bone Formation Process of β-TCP Ceramics with Tetracycline Tracing

To study the new bone formation in the bone defect area after implantation, the tetracycline tracing method was used. The results show that new bone formed in 1 month, and the formation rate of new bone was very high (8. 164 μm/day), considerably faster than that of control groups (3.219 μm/day). The new bone grew up quickly and β_TCP particles were surrounded by double fluorescence bands which became more obvious. The new bone formation rate was maximal at 2 months, and then gradually reduced. The rate was steady at 4 months, and then reduced to resembling as the normal physiologic metabolism of bone, which indicated the implanted materials were completely replaced by bone. Calcium phosphate materials had the ability of osteoconduction.     

FCM200高级电力监控仪的应用介绍

由于供电线路故障、浪涌、断线或其它干扰都可能导致电力系统服务中断 ,而FCM2 0 0电力监控仪可在线进行谐波分量测量 ,具备数字波形高速采集功能 ,它的波形分析工具可诊断谐波等故障根源 ,并且有助于确定必要的保护措施。     

Lanthanum Containing Polymer''s Modification to PP

Polypropylene (PP)'s low impact strength limits its usages. Adding some a rare earth polymer can enhance PP's tensile strength and impact strength. Acrylic lanthanum was prepared by the reaction between lanthanum oxide and acrylic acid. The IR spectrum prove that and optimum reacting conditions are that the bulk ratio of La(AA) 3 and MMA is not less than one and temperature is about 80 ℃. Lanthanum containing Polymer were added into PP. When percent of addition only was 3%, strength were enhanced 10% , and impact strength 40%. SEM shows the compatibility of rare earth polymer and PP; lanthanum containing polymer can form physical crosslinking between PP's molecules, then every particle's surface connect with several PP molecules and the PP mechanical property were enhanced.     

XNode:一种新的利用RDBMS来存储与检索XML的方法

XML作为互联网上数据表示和交换的标准正在飞速发展,利用RDBMS来存储与检索XML文档是发展的一个趋势。文章提出了一种新的基于路径存储与检索XML文档的方法XNode,采用了前缀加序号的编码策略,并且给出了具体实现方法及实验结果。结果表明该方法的效率高,适用范围广。     

金属铕制备工艺的研究

本文采用正交实验的方法,研究了金属铕的制备工艺条件。实验结果表明,还原－蒸馏温度１１００℃,还原剂过量系数０．３,保温时间１．５小时,金属铕的纯度大于９９．９％,直收率大于９０％     

创新是企业发展的动力源泉

结合近年来济钢的创新实践,就创新在企业中的四个内涵：观念创新、技术创新、制度和机制创新、管理创新等分别展开讨论,指出创新是企业发展的动力源泉。