Measuring Non-Markovianity of Noise in the Cenrtal Spin System

In this thesis, we explore non-Markovian noise in the central spin system due to the coupling between the central spin and the environment. We use a solid state nuclear magnetic resonance system to do the experiment since we have control over both the central spin and environment. In particular, we can manipulate the interaction between the central spin and the environment and the interaction between spins from the environment to study their effects individually. A powder of triphenylphosphine is used in the experiment. A change of local field seen by the central spin caused by interaction between spins in the environment is measured experimentally. A quantitative measure of non-Markovianity of noise on the central spin and a method to estimate non-Markovianity using the randomized benchmarking protocol are introduced

Centralized Coded Caching with User Cooperation

In this paper, we consider the coded-caching broadcast network with user cooperation, where a server connects with multiple users and the users can cooperate with each other through a cooperation network. We propose a centralized coded caching scheme based on a new deterministic placement strategy and a parallel delivery strategy. It is shown that the new scheme optimally allocate the communication loads on the server and users, obtaining cooperation gain and parallel gain that greatly reduces the transmission delay. Furthermore, we show that the number of users who parallelly send information should decrease when the users' caching size increases. In other words, letting more users parallelly send information could be harmful. Finally, we derive a constant multiplicative gap between the lower bound and upper bound on the transmission delay, which proves that our scheme is order optimal.Comment: 9 pages, submitted to ITW201

ERP is the Key Point of Supply Chain Management

Information technology is changing the mode of customer service , material purchasing , price making in an enterprise .To keep advantage , an enterprise has to take supply chain management . By sharing information and making plans together, an enterprise and its providers , its customers ,can improve their whole logistic efficiency through supply chain management. ERP is classic of information management in modern enterprises. ERP manages and controls effectively every node of supply chain inside an enterprise. It’s the information flat on which an enterprise manages and makes decision. It is the key point of supply chain management