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961.
The recent increase in smartphone supply drives more users to utilize mobile financial services and it magnifies the importance of mobile security solutions. But it is not easy to defend cyber-attacks against financial services because the attacks get more diverse every year. The recent solution, OTP (one time password), is the most commonly used financial security measure to defend session attacks, but the downside is that it is hard to implement differentiated OTP creation mechanism to it. This research intends to solve the problem by suggesting Two-Factor authentication mechanism that utilizes graphical OTP. It is an extension of OTP mechanism which implements the graphical one time password to mobile financial security to reinforce mobile's way of authenticating with only ID and Password or digital certificate from banks; and it will defend against more diverse mobile hackings. 相似文献
962.
Shon HK Park J Choi I Park HM Moon DW Lee TG 《Journal of nanoscience and nanotechnology》2011,11(1):638-641
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging analysis was performed on murine macrophage cells treated with various concentrations of iron oxide (Fe3O4) nanoparticles, which are used as MRI contrast agents. First, murine macrophage cells were seeded on a slide glass for 24 hrs and treated with varying concentrations of Fe3O4 nanoparticles for 24 hrs. To expose a cross section of each cell and obtain a distribution of the nanoparticles inside the cells, the cells were sputtered using Bi ions after which the cross section of each cell was scanned and imaged using the focused cluster ion beam with a spatial resolution of 300 nm. Fe3O4 nanoparticles were found mainly in the cytoplasm region of the cells, not in the nucleus region of cells, suggesting that the uptake of the Fe3O4 nanoparticles were into the cytoplasm of cell, not into the nucleus of cell. Based on these observations, our protocol using mass imaging analysis would be a useful addition to the study of in vitro nanoparticle cytotoxicity. 相似文献
963.
In-Jin Shon Seung-Hoon Jo Jung-Mann Doh Jin-Kook Yoon Bang-Ju Park 《Ceramics International》2012,38(7):6035-6039
Nanopowders of FeAl and Al2O3 were synthesized from Fe2O3 and Al by high energy ball milling. The sizes of FeAl and Al2O3 were 4 and 57 nm, respectively. A dense nanostuctured FeAl–Al2O3 composite was consolidated by a high-frequency induction heated sintering method within two minutes from mechanically synthesized powders of FeAl and Al2O3. The grain size, sintering behavior and hardness of the sintered FeAl–Al2O3 composite were investigated. 相似文献
964.
Ping是windows系统自带的一款功能强大的工具软件,利用Ping可有效检刚网络之间连通性,从而快速判断和排除网络中出现的故障. 相似文献
965.
Jinok Shin Sanki Ji Woonghee Shon Hogil Lee Kuk Cho Sangdeok Park 《Journal of Intelligent and Robotic Systems》2011,61(1-4):15-27
This study focused on a development of attitude stabilization and a position (hovering) control scheme of the SFR (Small Flying Robot). The platform type of the SFR is a ducted-fan type OAV having a diameter of 30 cm. The attitude of the SFR was successfully stabilized by a PD control method. In the attitude control loop, the feedback states were angle and angular rates, which were outputs from an AHRS (Attitude Heading Reference System). The position of the SFR was controlled precisely by the LQI (Linear Quadratic Integration) method with a Kalman filter. In the position control loop, an ultrasonic positioning system was used for the 3D position reference, which was developed in a previous research. The proposed simple mathematical model could analyze dynamics and stability of the SFR. Also, the stabilities of the attitude control and the precision of the position control were verified by comparing and analyzing data of experiments and simulations. 相似文献