Hwang K.-H.,SungkyunkwanUniversity |
Zeng A.,SungkyunkwanUniversity |
Nam S.-H.,Sungkyunkwan University |
Ju D.-W.,SungkyunkwanUniversity |
And 3 more authors.
Science of Advanced Materials | Year: 2014
Nickel nanoparticles were electro-deposited on nitrogen-doped diamond-like carbon (N-DLC) thin film surface at potentials ranging from -1.1 to -1.4 V versus Ag/AgCl in 0.1 M Na2SO4 aqueous solution containing 4 mM NiCl2. Atomic force microscopy was used to investigate the growth of the nanoparticles. The mean growth rate of the nanoparticles increased, whereas the nucleation density decreased with more negative deposition potential. At more negative potentials, large nanoparticles were obtained. The growth kinetics was studied by the dependence of potentiostatic current density on the deposition time, and the growth mechanism was explained by the cyclic voltammogram of the N-DLC film electrode in the deposition solution. The non-uniform size (height, area, and volume) of the nanoparticles would be attributed to the progressive nucleation and growth. The sharp hydrogen evolution at the deposition potential more negative than -1.1 V contributed to the decrease in nucleation density. Therefore, the nucleation density of the nickel nanoparticles can be manipulated by the deposition potential. © 2014 by American Scientific Publishers.
Koh M.S.,Sahmyook University |
International Journal of Applied Engineering Research | Year: 2014
The purpose of this study was development of sanitation and hygiene improvement education program and test its’ effects through 75 health workers in Uganda, The results was that health workers were satisfied after they received the education about content themes, materials used and allocated education time. © Research India Publications.
Lee E.,SungkyunkwanUniversity |
European Physical Journal B | Year: 2016
In ad hoc wireless networking, units are connected to each other rather than to acentral, fixed, infrastructure. Constructing and maintaining such networks create severaltrade-off problems between robustness, communication speed, power consumption, etc., thatbridges engineering, computer science and the physics of complex systems. In this work, weaddress the role of mobility patterns of the agents on the optimal tuning of a small-worldtype network construction method. By this method, the network is updated periodically andheld static between the updates. We investigate the optimal updating times for differentscenarios of the movement of agents (modeling, for example, the fat-tailed trip distances,and periodicities, of human travel). We find that these mobility patterns affect the powerconsumption in non-trivial ways and discuss how these effects can best be handled. © 2016, EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.