The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation （EC）. Firstly, the similarity of signat...The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation （EC）. Firstly, the similarity of signature curve segment is defined, and shift and scale transforms are also introduced due to the randoness of on-line signature. Secondly, this paper puts forward signature verification matching algorithm after establishment of the mathematical model. Thirdly, the concrete realization of the algorithm based on EC is discussed as well. In addition, the influence of shift and scale on the matching result is fully considered in the algorithm. Finally, a computation example is given, and the matching results between the test sample curve and the template signature curve are analyzed in detail, The preliminary experiments reveal that the type of signature verification problem can be solved by EC.展开更多
As a discipline, software engineering is not as mature as other engineering disciplines, and it still lacks consensus on a well-recognized set of fundamental principles. A 2006 analysis surveyed and analyzed 308 separ...As a discipline, software engineering is not as mature as other engineering disciplines, and it still lacks consensus on a well-recognized set of fundamental principles. A 2006 analysis surveyed and analyzed 308 separate proposals for principles of software engineering, of which only thirty-four met the criteria to be recognized as such. This paper reports on a further analysis of these thirty-four candidate principles using two sets of engineering criteria derived from: A) the engineering categories of knowledge defined by Vincenti in his analysis of engineering foundations;and B) the joint IEEE and ACM software engineering curriculum. The outcome of this analysis is a proposed set of nine software engineering principles that conform to engineering criteria.展开更多
油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形...油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形式能量,而油箱内部压强骤升是电气网络故障显著、快速的非电量表征。为此,建立变压器油箱内、外部故障压力特征模型,根据故障与非故障状态下油箱内部压力特征差异构造基于压力特征的变压器数字式保护。以63 MVA/220 k V变压器为例,仿真验证不同运行情况下的保护动作特性,结果表明:新原理正确可行,动作速度较传统瓦斯保护显著提高,能够灵敏甄别绕组小匝数短路故障,且本质上不受励磁涌流影响。展开更多
基金Supported by the National Natural Science Foun-dation of China (60496315)
文摘The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation （EC）. Firstly, the similarity of signature curve segment is defined, and shift and scale transforms are also introduced due to the randoness of on-line signature. Secondly, this paper puts forward signature verification matching algorithm after establishment of the mathematical model. Thirdly, the concrete realization of the algorithm based on EC is discussed as well. In addition, the influence of shift and scale on the matching result is fully considered in the algorithm. Finally, a computation example is given, and the matching results between the test sample curve and the template signature curve are analyzed in detail, The preliminary experiments reveal that the type of signature verification problem can be solved by EC.
文摘As a discipline, software engineering is not as mature as other engineering disciplines, and it still lacks consensus on a well-recognized set of fundamental principles. A 2006 analysis surveyed and analyzed 308 separate proposals for principles of software engineering, of which only thirty-four met the criteria to be recognized as such. This paper reports on a further analysis of these thirty-four candidate principles using two sets of engineering criteria derived from: A) the engineering categories of knowledge defined by Vincenti in his analysis of engineering foundations;and B) the joint IEEE and ACM software engineering curriculum. The outcome of this analysis is a proposed set of nine software engineering principles that conform to engineering criteria.
文摘油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形式能量,而油箱内部压强骤升是电气网络故障显著、快速的非电量表征。为此,建立变压器油箱内、外部故障压力特征模型,根据故障与非故障状态下油箱内部压力特征差异构造基于压力特征的变压器数字式保护。以63 MVA/220 k V变压器为例,仿真验证不同运行情况下的保护动作特性,结果表明:新原理正确可行,动作速度较传统瓦斯保护显著提高,能够灵敏甄别绕组小匝数短路故障,且本质上不受励磁涌流影响。
