In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' ...In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' of the job on position i and a “normal' processing time of the job. The criteria considered is to minimize scheduled length of all jobs. A lemma is proposed and proved. In no deadline constrained condition, the problem belongs to polynomial time algorithm. It is proved by using 3 partition that if the problem is deadline constrained, its complexity is strong NP hard. Finally, a conjuncture is proposed that is to be proved.展开更多
NP(non-deterministic polynomial)证据加密(witness encryption,WE)是近来提出的一种新型的没有密钥生成过程的加密方案,可以用来构建许多其他的密码系统如公开密钥加密、IBE(identity based encryption)、ABE(attribute based encrypt...NP(non-deterministic polynomial)证据加密(witness encryption,WE)是近来提出的一种新型的没有密钥生成过程的加密方案,可以用来构建许多其他的密码系统如公开密钥加密、IBE(identity based encryption)、ABE(attribute based encryption)等。该文提出WE的一种新应用:用WE构建可撤销广播加密系统,并且所构建的广播加密方案能支持简单的成员重加入功能(如付费电视);在构建的过程中指出以前的WE安全性定义不够严格,对原WE安全性定义进行了增强,并基于原WE方案和子集成员分辨难题、ROM(random oracle model)模型提出了一个新方案。展开更多
对单机环境下紧急工作的重调度问题进行了研究.初始调度中工作带有到达时间,目标为最小化初始工作的等待时间和;重调度目标是在初始调度锁定的情况下,将紧急工作插入初始调度,最小化紧急工作的最长等待时间.建立了RRLS(rescheduling rus...对单机环境下紧急工作的重调度问题进行了研究.初始调度中工作带有到达时间,目标为最小化初始工作的等待时间和;重调度目标是在初始调度锁定的情况下,将紧急工作插入初始调度,最小化紧急工作的最长等待时间.建立了RRLS(rescheduling rush jobs with loads locked on single machine)问题模型,然后证明了RRLS问题是NP难问题.根据问题性质和特点提出了有效的启发式算法,并给出了算法的时间复杂度.通过实例证明了算法的最优性条件.展开更多
文摘In this paper, single machine scheduling problems with variable processing time is discussed according to published instances of management engineering. Processing time of a job is the product of a “coefficient' of the job on position i and a “normal' processing time of the job. The criteria considered is to minimize scheduled length of all jobs. A lemma is proposed and proved. In no deadline constrained condition, the problem belongs to polynomial time algorithm. It is proved by using 3 partition that if the problem is deadline constrained, its complexity is strong NP hard. Finally, a conjuncture is proposed that is to be proved.
文摘NP(non-deterministic polynomial)证据加密(witness encryption,WE)是近来提出的一种新型的没有密钥生成过程的加密方案,可以用来构建许多其他的密码系统如公开密钥加密、IBE(identity based encryption)、ABE(attribute based encryption)等。该文提出WE的一种新应用:用WE构建可撤销广播加密系统,并且所构建的广播加密方案能支持简单的成员重加入功能(如付费电视);在构建的过程中指出以前的WE安全性定义不够严格,对原WE安全性定义进行了增强,并基于原WE方案和子集成员分辨难题、ROM(random oracle model)模型提出了一个新方案。
文摘对单机环境下紧急工作的重调度问题进行了研究.初始调度中工作带有到达时间,目标为最小化初始工作的等待时间和;重调度目标是在初始调度锁定的情况下,将紧急工作插入初始调度,最小化紧急工作的最长等待时间.建立了RRLS(rescheduling rush jobs with loads locked on single machine)问题模型,然后证明了RRLS问题是NP难问题.根据问题性质和特点提出了有效的启发式算法,并给出了算法的时间复杂度.通过实例证明了算法的最优性条件.
