As a non-sufficient but necessary condition for economic growth, human capital's contributions to economic growth depend largely on relevant system factors.
人力资本只是经济增长的必要而非充分条件，它对经济增长的贡献还要受相关的制度因素影响。
2
Message authentication by using a digital signature is not sufficient for non-repudiation.
使用数字签名的消息身份验证还不能满足不可抵赖性的条件。
3
Therefore, it seems that using SOAP-DSIG and SSL simultaneously is sufficient for non-repudiation, so I will now present two attacks by malicious recipients (not by third parties).