Vertex-based inter-frame boundary encoding scheme

The boundary is approximated by a polygon which can be encoded with the smallest number of bits for maximum distortion. The temporal redundancy between two successive frames is efficiently removed with the proposed scheme, resulting in a lower bit rate than the conventional algorithms     

Active object search in an unknown large-scale environment using commonsense knowledge and spatial relations

Intelligent Service Robotics - In this study, the goal is to efficiently and actively search for a target object in a previously unknown large-scale environment. To this end, we develop a...     

Molecular dynamics study on the effect of solution-wall interaction potential on the properties of solution in uniformly charged hydrophobic channel

We numerically investigate the effect of the solution-wall (i.e., water-wall and ion-wall) interaction potential on the properties of confined aqueous solution by using molecular dynamics (MD) simulations. The effect is determined by comparing results obtained from the MD simulation using the Lennard-Jones (L-J) potential for the water-wall and ion-wall interactions and those using a purely repulsive potential, i.e., the Weeks-Chandler-Andersen-like potential. In the MD simulations, 680 water molecules and 20 chloride ions are included between uniformly charged plates that are separated by 2.6 nm. The results show that the properties of solution are influenced only in the region close to the wall: The water molecules are more densely packed for the case of the L-J potential. Comparison of the results of the MD simulations in the case of the L-J potential with those provided by solving the Poisson-Boltzmann equation, we found that classical continuum theory fails to predict the ion density and electrostatic potential distributions in the region near to the wall, but far way from the wall, the prediction from the continuum theory is in line with the MD simulation.     

Release behavior of active material from poly(vinyl amine)/polyelectrolyte composite hollow particles

Polyvinyl amine (PVAm) hydrogel hollow particles treated by layer-by-layer (LbL) assembly methods were fabricated. The structures of the prepared particles were confirmed through zeta-potential measurements and scanning electron microscopy (SEM). In addition, the loading amount and release rate of Chromotrope 2R (CR) from the prepared particles in each deposition step was investigated. The loading amount had an alternating tendency according to an increase in the layer number. When the outermost layer consisted of poly(sodium 4-styrenesulfonate) (PSS), CR permeation was prevented by ionic repulsion between the PSS and CR. On the other hand, CR easily permeated into the particles when the outermost layer was poly(diallyldimethyl ammonium chloride) (PDDA). The release rate was then changed by ionic interaction between the CR and the cationic polyelectrolyte and by the ionic repulsive force between the CR and the anionic polyelectrolyte. These results indicate that PVAm hydrogel hollow particles treated by the LbL method could potentially be used in the controlled release of water-soluble materials.     

Enhancement of the punch pin durability induced by the PVD coating in production process of the automotive inner pipe

This experimental studies were carried out in order to understand the effects of the PVD coating and the UNSM treatment of HSS55 (high speed steel 55) during the production of the automotive inner pipe by the plastic deformation of S45C. The field test and the SEM images revealed that the PVD coating is necessary in spite of the high compressive residual stresses which were formed at the head of a punch pin. Upon the application of the AlCrN coating with the UNSM treatment the productivity and reliability of a punch pin had improved more than about 2.6 times compared to that of the TiN coating without the UNSM treatment. It is likely that the improvement is caused by the decreased stress concentration factor by the ‘wrapped in oxides’ inside of an abrasion pit. The abrasion pits were mostly generated within range of 5% ∼ 50% of the diameter ratio from the end of a pin and reached the maximum value about 17% from the end of a pin.     

Decision on the memory size of embedded information systems in an ubiquitous maintenance environment

Over the last decade, emerging information communication technologies have changed our stereotype of manufacturing and service companies. Now products equipped with embedded systems can be wirelessly networked, which leads to gathering and analyzing product status, and taking appropriate actions for maintenance operations during product lifecycle in an ubiquitous way. In this environment, it is necessary to determine the appropriate memory size of embedded systems for minimizing total maintenance system costs because the memory cost is a main cost factor for implementing the ubiquitous maintenance environment. We call it memory size decision problem in this study. We have formulated this problem with a non-linear model having constraints. The decision variable is the memory size of each embedded system. To solve this problem, we have proposed a meta heuristic search method based on genetic algorithms. To show the usefulness of the proposed heuristic, we have carried out computational experiments.     

Charge distributions in PC/SAN/PCL polymer blends

The formation of space charge in polycarbonate (PC)/poly (styrene-co-acrylonitrile) (SAN) blends containing poly (ϵ-caprolactone) (PCL) as a compatibilizer for improving the miscibility, has been studied by measuring spatial charge distributions. It is found that the miscibility of PC/SAN blends is improved as the PCL content increases. The amount of charge accumulated in the blends decreases when the PCL content increases to 15% by weight and then increases when the PCL content is >15% wt. The decrease of charge at the PCL content <15% wt was attributed to the combined effects of changes in conductivities and the molecular interactions at the domain interfaces. The increase of charge at the PCL content >15% wt was attributed to the trapping of charge at the amorphous and crystalline phases of PC and PCL     

Effect of H2O evolving from TEOS based SiO2 film on the EEPROM cell characteristic

In this paper, we investigate the effect of water (H₂O) molecules evolving from silicon dioxide (SiO₂) film deposited by low pressure chemical vapor deposition (LPCVD) at 670 °C on the transistor characteristic of an electrically erasable programmable read only memory (EEPROM) cell. Fourier Transform Infra red (FT-IR) analysis reveals that H₂O is captured during film deposition and diffused to silicon surface during high thermal processing. The diffused H₂O molecules lower threshold voltage (V_t) of cell transistor and, thus, leakage current of the cell transistor is increased. In erased cell, V_t lowering is 0.25 V in which it increases leakage current of cell transistor from 1 to 100 pA. This results in the lowering of high voltage margin of a 512 Kb EEPROM from 2.8 to 2.6 V at 85 °C.