FLiP-ing insulators

Image flip CAPTCHA

The massive and automated access to Web resources through robots has made it essential for Web service providers to make some conclusion about whether the "user" is a human or a robot. A Human Interaction Proof (HIP) like Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) offers a way to make such a distinction. CAPTCHA is a reverse Turing test used by Web serv...

Evolut Ionary Schedul Ing and Rout Ing

The aim of this paper is to clearly demonstrate the importance of finding a good balance between genetic search and local search in the implementation of hybrid evolutionary multi-criterion optimization (EMO) algorithms. We first modify the local search part of an existing multi-objective genetic local search (MOGLS) algorithm. In the modified MOGLS algorithm, the computation time spent by loca...

Topological insulators

Chromatin insulators.

Active and silenced chromatin domains are often in close juxtaposition to one another, and enhancer and silencer elements operate over large distances to regulate the genes in these domains. The lack of promiscuity in the function of these elements suggests that active mechanisms exist to restrict their activity. Insulators are DNA elements that restrict the effects of long-range regulatory ele...

Converting normal insulators into topological insulators via tuning orbital levels

Wu-Jun Shi,1,2 Junwei Liu,3 Yong Xu,1,4,5,* Shi-Jie Xiong,2 Jian Wu,1,4 and Wenhui Duan1,4,† 1State Key Laboratory of Low-Dimensional Quantum Physics, and Department of Physics, Tsinghua University, Beijing 100084, People’s Republic of China 2National Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093, People’s Republic of China 3Department ...