Multi-Tips Objects

In this chapter the influence of the structural parameters on the optical behavior of silver nanoparticles is anal3fzed. The absorption and scattering spectra are obtained for particles with different size and shape in the framework of the discrete dipole approximation. Radially symmetric nanoparticles, as well as finite-number faces nanoparticles or multi-tips objects are investigated under the excitation of uniform fields impacting with different poiarizations and propagation directions. The optical responses can be assigned to the excitation of iocalized surface plasmon resonances of different order. The presented results can be used to interpret experimental measurements and/or to develop new high-performance substrates for molecular plasmonics applications. 

By starting from the maximum truncation of a regular decahedron which corresponds to a star decahedron (r = 1/2), in this section we will have a look at the optical behavior of multi-tips objects with the unique surface geometry consisting of several corners or thorns protruding from a central body. 

These structures are excited with a plane-wave propagating in the X direction and polarized along they direction. DDA tests done on the NUO structure revealed no significant modifications of the spectra for a 3D rotation of the scatterer and this in agreement with the fact that multi-tips objects like these have a major probability of favorable alignment with the incident radiation, as compared to simpler shapes such as nanorods [65]. 

In chapter 3, the model was evaluated and examined, which was proposed in chapter 2. Firstly, parameter identification method was proposed based on mechanism. We can identify adsorption parameter and dissociation parameter by observing the deformation response of the beam-shaped gel in uniform electric field. The tip position and orientation of beam-shaped gel is a function of internal state of the whole gel. Therefore, we can identify parameters through observation of the tip. Secondly, the method was extended to calibrate the parameters. Adsorption parameter mainly affects the deformation speed of the material, which also scatters. Two methods were considered in order to calibrate reaction parameter. One is to estimate it by the deformation response of the gel for a given period of time. Another is to do it by the time required to deform into the particular shape of the gel. Thirdly, the resolution was changed to digitize spatial and temporal variables. The convention deformable objects must be modeled with minute elements was broken down. It was made clear that beam-shaped gel whose length is 16 mm could be approximated into multi-link mechanism whose links are 1 mm in length. 

Alam, S., Lokan, C., Aldis, G., Barry, S., Butcher, R., Abbass, H. Systemic identification of airspace collision risk tipping points using an evolutionary multi-objective scenario-based methodology. Transportation Research Part C Emerging Technologies 35, 57-84... 

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