难

In th is paper, w e p ropo se a cert ificateless ring signature scheme, based on the bilinear pairings, w h ich p rovides uncondit ional anonym ity, and p rove th is scheme is existent ially un fo rgeable under adap t ive cho se2message at tack s, in the random o raclemodel, assum ing that the computat ionalD iffie2Hellman p roblem is hard to so lve.

摘 要 在这篇文章里，我们用双线性对构造了一种无证书的环签名方案，并证明它是无条件匿名的，且在随机预言模型中，计算性D iffie2Hellman 问题是难解的，我们方案在适应性选择消息攻击下是存在性不可伪造的，它的安全性比在基于身份的公钥密码体制下高。

How easy it is to put on and take off depends on how you fit into the Anorak.

你脱与穿的难易程度取决于你适合不适合 Anorak 。

It was difficult to explain their antagonism towards strangers.

很难解释他们对陌生人的敌意。

However ,due to their age , poor comprehension and antagonization,it is different to achive satisfactory resrlts while using the same mode of teaching.

然而，由于他们的年龄相对较小，理解力较差，而且有逆反心理，如果都用同一模式进行教学，很难收到理想的教学效果。

The world's coldest continent,and the most difficult to reach,is Antarctic.

世界上最冷的洲，也是最难到达的洲是南极洲。

Most/mostly The world's coldest continent,and the most difficult to reach,is Antarctic.

世界 上最冷的洲，也是最难到达的洲是南极洲。

It is difficult to imagine a more inhospitable place than Antarctica.

很难想象一个比南极洲更不适合居住的地方。

By late September, Antares will be tough to spot in the southwestern twilight after sunset.

在九月下下旬，当太阳下山，黄昏来临的西南部，心宿二就将很难被发现了。

It is hard now for Jews to talk about anti-Semitism even when it does exist.

现在已经很难在谈论犹太人的反犹主义，即使它确实存在。

At the age of 40, King Gillette was a frustrated inventor, a bitter anticapitalist, and a salesman of cork-lined bottle caps. It was 1895, and despite ideas, energy, and wealthy parents, he had little to show for his work. He blamed the evils of market competition.

King Gillette在40岁的时候是一个挫折的发明家，一个很苦的反资本主义者，以及一个软木塞瓶盖销售员，在没有构想、精神以及有钱的父母之下的1895年，他很难发挥它的工作。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。