@article{zhao_gao_nie_zhou_2022, title={A Survey of GPU Multitasking Methods Supported by Hardware Architecture}, volume={33}, ISSN={["1558-2183"]}, url={https://doi.org/10.1109/TPDS.2021.3115630}, DOI={10.1109/TPDS.2021.3115630}, abstractNote={The ability to support multitasking becomes more and more important in the development of graphic processing unit (GPU). GPU multitasking methods are classified into three types: temporal multitasking, spatial multitasking, and simultaneous multitasking (SMK). This article first introduces the features of some commercial GPU architectures to support multitasking and the common metrics used for evaluating the performance of GPU multitasking methods, and then reviews the GPU multitasking methods supported by hardware architecture (i.e., hardware GPU multitasking methods). The main problems of each type of hardware GPU multitasking methods to be solved are illustrated. Meanwhile, the key idea of each previous hardware GPU multitasking method is introduced. In addition, the characteristics of hardware GPU multitasking methods belonging to the same type are compared. This article also gives some valuable suggestions for the future research. An enhanced GPU simulator is needed to bridge the gap between academia and industry. In addition, it is promising to expand the research space with machine learning technologies, advanced GPU architectural innovations, 3D stacked memory, etc. Because most previous GPU multitasking methods are based on NVIDIA GPUs, this article focuses on NVIDIA GPU architecture, and uses NVIDIA's terminology. To our knowledge, this article is the first survey about hardware GPU multitasking methods. We believe that our survey can help the readers gain insights into the research field of hardware GPU multitasking methods.}, number={6}, journal={IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS}, publisher={Institute of Electrical and Electronics Engineers (IEEE)}, author={Zhao, Chen and Gao, Wu and Nie, Feiping and Zhou, Huiyang}, year={2022}, month={Jun}, pages={1451–1463} }
 @article{zhao_sichitiu_rhee_2015, title={N-body: A social mobility model with support for larger populations}, volume={25}, ISSN={["1570-8713"]}, DOI={10.1016/j.adhoc.2014.10.005}, abstractNote={An accurate reproduction of real human movement is essential in simulations of MANETs in order to obtain meaningful performance results. Existing models capturing real world mobility features often require knowledge of the underlying dynamics of the target scenario, therefore limiting the application scope. In this paper we tackle this problem from a different perspective. Rather than considering the details of the target scenario, we extract features from a sample trace, and synthesize traces that have similar features. In particular, as human activities are often socially organized, resulting in a tendency of forming groups, we propose an N-body mobility model that captures the group forming tendency from traces of a small number of nodes, and reproduces them in mobility traces of a larger population. Through simulation we show that the N-body model is capable of synthesizing the group forming behavior similar to that observed from sample traces.}, journal={AD HOC NETWORKS}, author={Zhao, Chen and Sichitiu, Mihail L. and Rhee, Injong}, year={2015}, month={Feb}, pages={185–196} }
 @article{zhao_sichitiu_2011, title={Contact time in random walk and random waypoint: Dichotomy in tail distribution}, volume={9}, ISSN={["1570-8713"]}, DOI={10.1016/j.adhoc.2010.03.005}, abstractNote={Contact time (or link duration) is a fundamental factor that affects performance in Mobile Ad Hoc Networks. Previous research on theoretical analysis of contact time distribution for random walk models (RW) assume that the contact events can be modeled as either consecutive random walks or direct traversals, which are two extreme cases of random walk, thus with two different conclusions. In this paper we conduct a comprehensive research on this topic in the hope of bridging the gap between the two extremes. The conclusions from the two extreme cases will result in a power-law or exponential tail in the contact time distribution, respectively. However, we show that the actual distribution will vary between the two extremes: a power-law-sub-exponential dichotomy, whose transition point depends on the average flight duration. Through simulation results we show that such conclusion also applies to random waypoint.}, number={2}, journal={AD HOC NETWORKS}, author={Zhao, Chen and Sichitiu, Mihail L.}, year={2011}, month={Mar}, pages={152–163} }