The methods of moment and genetic algorithm (GA) are combined to optimize the Yagi Uda antenna array and Log periodic dipole antenna (LPDA) array. The element lengths and spacing are optimized for the Yagi Uda arra...The methods of moment and genetic algorithm (GA) are combined to optimize the Yagi Uda antenna array and Log periodic dipole antenna (LPDA) array. The element lengths and spacing are optimized for the Yagi Uda array; while the ratio factor of spacing to length as well as the ratio of length to diameter of the elements are optimized for LPDA array. The results show that the main parameters, such as gain and pattern, have been improved apparently; and the high back lobe level of LPDA can be reduced greatly, therefore, GA is a very competent method for optimizing the linear array as well as in other fields.展开更多
随着数据访问技术的发展,微软为开发人员在数据库访问方面提供了非常强大技术支持,使开发 人员在访问数据库时更加得心应手。ADO(ActiveX Data Objeets-活动数据对象)技术是微软最近推出的比 较成熟、数据访问更简单、功能更强大的数据...随着数据访问技术的发展,微软为开发人员在数据库访问方面提供了非常强大技术支持,使开发 人员在访问数据库时更加得心应手。ADO(ActiveX Data Objeets-活动数据对象)技术是微软最近推出的比 较成熟、数据访问更简单、功能更强大的数据库访问方法,本文就ADO的相关技术作一些介绍和探讨。展开更多
文摘The methods of moment and genetic algorithm (GA) are combined to optimize the Yagi Uda antenna array and Log periodic dipole antenna (LPDA) array. The element lengths and spacing are optimized for the Yagi Uda array; while the ratio factor of spacing to length as well as the ratio of length to diameter of the elements are optimized for LPDA array. The results show that the main parameters, such as gain and pattern, have been improved apparently; and the high back lobe level of LPDA can be reduced greatly, therefore, GA is a very competent method for optimizing the linear array as well as in other fields.
文摘随着数据访问技术的发展,微软为开发人员在数据库访问方面提供了非常强大技术支持,使开发 人员在访问数据库时更加得心应手。ADO(ActiveX Data Objeets-活动数据对象)技术是微软最近推出的比 较成熟、数据访问更简单、功能更强大的数据库访问方法,本文就ADO的相关技术作一些介绍和探讨。
