移动群智感知系统(MCS)能否高效地运行,很大程度上取决于是否有大量任务参与者参与到感知任务中。然而在现实中,用户的感知成本增加以及用户的隐私泄露等原因,导致用户的参与积极性不高,因此需要一种有效的手段,用于在保证用户隐私安全...移动群智感知系统(MCS)能否高效地运行,很大程度上取决于是否有大量任务参与者参与到感知任务中。然而在现实中,用户的感知成本增加以及用户的隐私泄露等原因,导致用户的参与积极性不高,因此需要一种有效的手段,用于在保证用户隐私安全的同时,还能促进用户积极地参与到任务中。针对上述问题,结合本地化差分隐私保护技术,提出了一种基于综合评分的双边拍卖隐私激励机制(Privacy Incentive Mechanism of Bilateral Auction with Comprehensive Scoring, BCS),这种激励机制包括拍卖机制、数据扰动和聚合机制以及奖励和惩罚机制3个部分。拍卖机制综合考虑了各种因素对用户完成感知任务的影响,在一定程度上提高了任务的匹配程度;数据扰动和聚合机制在隐私保护和数据精度之间做出权衡,在保证数据质量的同时做到了对用户隐私的良好保护;奖励和惩罚机制奖励诚信度和活跃度高的用户,激励用户积极参与感知任务。实验结果表明,BCS可以在提高平台收益和任务匹配率的同时保证感知数据的质量。展开更多
Anisotropic nanopatterns have potentials in constructing novel plasmonic structures which have various applications in such as super-resolution microscopy, medicine, and sensors. However, it remains challenging to bui...Anisotropic nanopatterns have potentials in constructing novel plasmonic structures which have various applications in such as super-resolution microscopy, medicine, and sensors. However, it remains challenging to build big anisotropic nanopatterns that are suitable for big noble metal nanoparticles. Herein, we report a simple and reliable strategy for constructing DNA origami-based big anisotropic nanopatterns with controlled size and shape, nanoscale resolution, and fully addressability. Two kinds of basic DNA origami nanoblocks-cross-shaped and rectangular DNA origami units were used. We have demonstrated that by encoding nanoblocks' edges, anisotropic higher-order nanopatterns, such as dimer, trimer, tetramer and mini "windmill" like pentamer nanopatterns could be constructed. To show the potential use as template to direct the assembly of anisotropic nanoparticles arrays, a proof of concept work was conducted by anchoring streptavidin nanoparticles on the "windmill" template to form a chiral array. Significantly, these nanopatterns have the sizes of hundreds of nanometers, which are in principle also suitable for big noble metal nanoparticles arrays.展开更多
文摘移动群智感知系统(MCS)能否高效地运行,很大程度上取决于是否有大量任务参与者参与到感知任务中。然而在现实中,用户的感知成本增加以及用户的隐私泄露等原因,导致用户的参与积极性不高,因此需要一种有效的手段,用于在保证用户隐私安全的同时,还能促进用户积极地参与到任务中。针对上述问题,结合本地化差分隐私保护技术,提出了一种基于综合评分的双边拍卖隐私激励机制(Privacy Incentive Mechanism of Bilateral Auction with Comprehensive Scoring, BCS),这种激励机制包括拍卖机制、数据扰动和聚合机制以及奖励和惩罚机制3个部分。拍卖机制综合考虑了各种因素对用户完成感知任务的影响,在一定程度上提高了任务的匹配程度;数据扰动和聚合机制在隐私保护和数据精度之间做出权衡,在保证数据质量的同时做到了对用户隐私的良好保护;奖励和惩罚机制奖励诚信度和活跃度高的用户,激励用户积极参与感知任务。实验结果表明,BCS可以在提高平台收益和任务匹配率的同时保证感知数据的质量。
基金supported by the National Basic Research Program of China (2012CB932600)the National Natural Science Foundation of China(20725516, 90913014, 21028005 and 21103219)Shanghai Pujiang Program (11PJ1412000)
文摘Anisotropic nanopatterns have potentials in constructing novel plasmonic structures which have various applications in such as super-resolution microscopy, medicine, and sensors. However, it remains challenging to build big anisotropic nanopatterns that are suitable for big noble metal nanoparticles. Herein, we report a simple and reliable strategy for constructing DNA origami-based big anisotropic nanopatterns with controlled size and shape, nanoscale resolution, and fully addressability. Two kinds of basic DNA origami nanoblocks-cross-shaped and rectangular DNA origami units were used. We have demonstrated that by encoding nanoblocks' edges, anisotropic higher-order nanopatterns, such as dimer, trimer, tetramer and mini "windmill" like pentamer nanopatterns could be constructed. To show the potential use as template to direct the assembly of anisotropic nanoparticles arrays, a proof of concept work was conducted by anchoring streptavidin nanoparticles on the "windmill" template to form a chiral array. Significantly, these nanopatterns have the sizes of hundreds of nanometers, which are in principle also suitable for big noble metal nanoparticles arrays.
