In this paper, a discrete stage - structured epidemical model is proposed and studied.本文主要讨论了离散的阶段结构传染病模型.OBJECTIVE To explore the administration measures of air condition usage in SARS epidemical period.目的研究传染性非典型肺炎流行期间...
Such estimates should be considered only as crude approximations.上述估算结果只能是粗略的近似值.There are two approaches generally used to arrive at these approximations.通常有两种方法用于获得近似解析式.They are not second - order approximations, but ...
She designs for a firm of dressmakers.她为一家女服饰店设计图样.Eventually these dressmakers and tailors began to establish their own shops where custom - made clothing and sold.后来,服装生产者或裁缝们开始建立自己的店铺,专门帮人们定做衣服....
电影制片人常常被指责美化了集团犯罪。Filmmakers have often been accused of glamorizing organized crime.野外生活被过分美化了。Life in the wild is vastly overrated.电视往往美化暴力。Television tends to glamorize violence....
这话对不住我亲爱的历史老师，不过有谁需要历史课呢？With apologies to my old history teacher, who needs history lessons?今天历史课指定的作业是什么?What is today's assignment in history?教师利用城堡图画讲解历史课.The teacher illustrated the history lesson with pictures...