简介：摘要：随着移动互联网的发展，尤其是智能手机的普及，近场通讯NFC技术随之发展，但在其发展过程中，NFC技术还不够完善，存在着安全性和不稳定性的威胁，严重制约这NFC技术的发展以及延伸，制约着NFC技术的使用和普及，为了保障NFC技术使用过程中的安全和稳定，本文提出了安全性和不稳定性的问题，并针对问题做出解决方法，且分析了解决方法对于问题的有效性，相信通过这些解决办法，有助于构建一种更加安全和稳定的NFC技术。

简介：

简介：摘要：近场通信（New Field Communication）， 即 NFC 技术，是由非接触式射频识别技术（RFID）和互连互通技术融合发展而来。NFC技术是一种短距离高频无线电技术，能够在移动设备、消费电子产品、PC和智能控件工具间进行近距离无线通信。近年来，随着技术的不断进步，NFC技术得到了迅速发展，其应用领域不断扩大，功能也逐渐丰富。利用了 NFC 技术的系统之间可以在距离较近的情况下进行数据之间通信的一种新技术。手机支付通过点对点通信设备的功能集成，如电感阅读器、电感芯片、电子票务、门禁控制、移动证件识别和电子防伪等，利用手机客户端就可以实现。在发展过程中，近场通讯技术还不够完善，存在着安全性和不稳定性等威胁，严重制约这NFC技术的发展以及延伸，制约着NFC技术的使用和普及，为了保障NFC技术使用过程中的安全和稳定，本文提出了近场通讯存在的问题及研究对策。

简介：AbstractBackground:Data on the immunogenicity and safety of heterologous immunization schedules are inconsistent. This study aimed to evaluate the immunogenicity and safety of homologous and heterologous immunization schedules.Methods:Multiple databases with relevant studies were searched with an end date of October 31, 2021, and a website including a series of Coronavirus disease 2019 studies was examined for studies before March 31, 2022. Randomized controlled trials (RCTs) that compared different heterologous and homologous regimens among adults that reported immunogenicity and safety outcomes were reviewed. Primary outcomes included neutralizing antibodies against the original strain and serious adverse events (SAEs). A network meta-analysis (NMA) was conducted using a random-effects model.Results:In all, 11 RCTs were included in the systematic review, and nine were ultimately included in the NMA. Among participants who received two doses of CoronaVac, another dose of mRNA or a non-replicating viral vector vaccine resulted in a significantly higher level of neutralizing antibody than a third CoronaVac 600 sino unit (SU); a dose of BNT162b2 induced the highest geometric mean ratio (GMR) of 15.24, 95% confidence interval [CI]: 9.53-24.39. Following one dose of BNT162b2 vaccination, a dose of mRNA-1273 generated a significantly higher level of neutralizing antibody than BNT162b2 alone (GMR = 1.32; 95% CI: 1.06-1.64), NVX-CoV2373 (GMR = 1.60; 95% CI: 1.16-2.21), or ChAdOx1 (GMR = 1.80; 95% CI: 1.25-2.59). Following one dose of ChAdOx1, a dose of mRNA-1273 was also more effective for improving antibody levels than ChAdOx1 (GMR = 11.09; 95% CI: 8.36-14.71) or NVX-CoV2373 (GMR= 2.87; 95% CI: 1.08-3.91). No significant difference in the risk for SAEs was found in any comparisons.Conclusions:Relative to vaccination with two doses of CoronaVac, a dose of BNT162b2 as a booster substantially enhances immunogenicity reactions and has a relatively acceptable risk for SAEs relative to other vaccines. For primary vaccination, schedules including mRNA vaccines induce a greater immune response. However, the comparatively higher risk for local and systemic adverse events introduced by mRNA vaccines should be noted.Registration:PROSPERO; https://www.crd.york.ac.uk/PROSPERO/; No. CRD42021278149.