中文摘要：

对孙培勇等人提出的多候选人电子投票方案进行了安全分析,指出其存在的安全问题,并利用分布式ElGamal加密体制的同态性给出了一个安全的改进方案.

英文摘要：

It analyzes the security of the electronic voting scheme with multi-candidate pro- posed by Sun et al. and point out its security problems. It also gives an improved electronic voting scheme with multi-candidate via using the property of homomophism in the distributed ElGamal encryption scheme.