With rapid advances of solar blind ultraviolet LED and ultraviolet detecting technology in recent years, ultraviolet communication gradually becomes a research hotspot due to its inherent advantages: low solar backgro...With rapid advances of solar blind ultraviolet LED and ultraviolet detecting technology in recent years, ultraviolet communication gradually becomes a research hotspot due to its inherent advantages: low solar background noise, non-line-of-sight(NLOS) and good secrecy. The strong scattering characteristics in atmospheric render ultraviolet waveband the ideal choice for achieving NLOS optical communication. This paper reviews the research history and status of ultraviolet communication both in China and abroad, and especially introduces three main issues of ultraviolet communication: channel model, system analysis and design, light sources and detectors. For each aspect, current open issues and prospective research directions are analyzed.展开更多
Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the s...Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles.展开更多
We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological appli...We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological applications. A potent peptide inhibitor of estrogen receptor α(ER-α) with significantly increased cellular uptake and cellular distribution was developed by cell penetrating peptide attachment.The resulted peptide conjugate showed selective toxicity towards estrogen receptor positive cell lines and induced decreased transcription of estrogen receptor a downstream genes.展开更多
基金supported by the National High-tech R&D Program of China grant 2015AA043302the Basic research project of Shenzhen grant JCYJ20140417115840236
文摘With rapid advances of solar blind ultraviolet LED and ultraviolet detecting technology in recent years, ultraviolet communication gradually becomes a research hotspot due to its inherent advantages: low solar background noise, non-line-of-sight(NLOS) and good secrecy. The strong scattering characteristics in atmospheric render ultraviolet waveband the ideal choice for achieving NLOS optical communication. This paper reviews the research history and status of ultraviolet communication both in China and abroad, and especially introduces three main issues of ultraviolet communication: channel model, system analysis and design, light sources and detectors. For each aspect, current open issues and prospective research directions are analyzed.
文摘Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles.
基金financial support from the National Natural Science Foundation of China (Nos. 21778009 and 81701818 MOST2015DFA31590)the Shenzhen Science and Technology Innovation Committee (Nos. JCYJ20170412150719814 and GJHS20170310093122365)
文摘We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological applications. A potent peptide inhibitor of estrogen receptor α(ER-α) with significantly increased cellular uptake and cellular distribution was developed by cell penetrating peptide attachment.The resulted peptide conjugate showed selective toxicity towards estrogen receptor positive cell lines and induced decreased transcription of estrogen receptor a downstream genes.