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In the present work, to build a water splitting system using only a neutral electrolyte solution and light source, we investigated the photoelectrochemical properties and interface resistances of an IrO2-coated TiO2 photoanode in Z-scheme configuration. The photoelectrochemical cell was connected to the perovskite solar cell with to realize the system with no need for an external electrical bias. Photoanodes with IrO2 were found to support hole transport and to reduce the overpotential, therefore increasing the current density of the system consisting of photoelectrochemical cells. A maximum solar-to-hydrogen efficiency of 8.2% was achieved in a neutral electrolyte. [ABSTRACT FROM AUTHOR]

The photodiode converts incident light into a microcurrent that flows when photons of sufficient energy strike the device under reverse bias. In doing so, a leakage current is caused by the reverse bias. In order to decrease the leakage current, buffer layers are introduced as electron- and hole-blocking materials between the photoactive material and electrode. We fabricated an organic photodiode using Ga-doped NiOx as an electron-blocking layer and investigated the physical effects of Ga doping on the performance of the organic photodiode. Our results showed that this diode exhibited high detectivity of 1.06 × 1012 Jones. [ABSTRACT FROM AUTHOR]

The structure-property relationship of partially aliphatic copolyimides has been studied for the development of flexible, transparent polyimide films. A structurally rigid cycloaliphatic dianhydride and three aromatic dianhydrides having different structural flexibility were reacted with 4,4′-oxydianiline to prepare the copolyimides. In order to control the balance between aromaticity and aliphaticity and between rigidity and flexibility of the copolyimides, the molar ratio of the dianhydrides was varied. Polyimide properties such as viscosity, solubility, optical transparency, color, dielectric constants, film flexibility and thermal stability are influenced by aromaticity/aliphaticity and/or flexibility/rigidity of the monomers. [ABSTRACT FROM AUTHOR]

Three different new hole transport compounds, namely,2-[1-{4-(N,N-diphenylamino) phenyl}-3,4,5,6-tetraphenylbenzene-2-yl]5-N,N-diphenylaminopyridine(DPAP-TB), 2-[1-{4-(N-phenylnaphthalene-1-amino)phenyl}-3,4,5,6-tetraphenylbenzene-2-yl]5- (N-phenylnaphthalen-1-amino)pyridine(1-PNAP-TB) and 2-[1{4-(N-phenylnaphthal- en-1-amino)phenyl}-3,4-,5,6-tetraphenylbenzene-2-yl]-5-(N-phenylnaphthalen-2-amino)pyridine(2-PNAP-TB) were synthesized. Optical and electronic properties were examined by UV-Visible absorption spectrum and cyclic voltammetry. Luminance efficiencies and external quantum efficiencies of DPAP-TB, 1-PNAP-TB and 2-PNAP-TB were 3.72, 2.82, 3.30 cd/A, and 1.29, 0.97, 1.12% at 10 mA/cm2, respectively. Synthesized materials exhibited high Tgin the range of 118 to 133°C. These values are higher than that of NPB which is commonly used as a hole transporting material. [ABSTRACT FROM PUBLISHER]

High on-off ratio, low turn-on voltage and fast response time are most critical issues in the research and development of organic transistor. In the present work, we have fabricated vertical type organic transistor using 2,8-difluoro-indeno[1,2-b]fluorine-6,12-dione (IF-dione-F) as an organic active semiconductor and DMDCNQI as a n type buffer material. IF-dione-F shows n-type semiconductor property and relatively high electron mobility. The organic light emitting transistor (OLET) configuration is ITO (drain)/PEDOT:PSS/MEH-PPV/IF-dione-F/Metal (gate)/IF-dione-F/DMDCNQI/Metal (source). The characteristics of OLET were investigated from the measurements of current-radiance voltage characteristics, electron mobility and external quantum efficiency [ABSTRACT FROM PUBLISHER]

We present a method of simultaneous localization and mapping (SLAM) in a large indoor environment using a Rao-Blackwellized particle filter (RBPF) along with a line segment as a landmark. To represent the environment in a compact form, we use only two end points of a line segment, thus reducing computational cost in modeling line segment uncertainty. With a modified scan point clustering method, the proposed adaptive iterative end point fitting contributes to the estimation of line parameters by considering noisy scan points near end points. Thus, by line segment matching the robot is localized well in a local frame. We also introduce an online and offline method of global line merging, which provides a more compact map by removing spurious lines and merging collinear lines. Each of our approaches is efficiently integrated into the proposed RBPF-SLAM framework. In experiments with well-known data sets, the proposed method provides reliable SLAM and compact map representation even in a cluttered environment. [ABSTRACT FROM AUTHOR]

We propose a real-time pose-invariant face recognition algorithm from a gallery of frontal images only. (i) We modified the second-order minimization method for the active appearance model (AAM). This allows the AAM to have the ability of correct convergence with little loss of frame rate. (ii) We proposed a pose transforming matrix that can eliminate warping artifacts of the warped face image from AAM fitting. This makes it possible to train a neural network as the face recognizer with one frontal face image of each person in the gallery set. (iii) We propose a simple method for pose recognition by using neural networks to select the proper pose transforming matrix. The proposed algorithm was evaluated on a set of 2000 facial images of 10 people (200 images for each person obtained at various poses), achieving a great improvement in recognition. [ABSTRACT FROM AUTHOR]

We have fabricated static induction transistor of vertical type using C60 with high carrier mobility as n-type organic semiconductor material to improve the characteristics of organic transistor. The effects of thin film thickness and the rate of deposition on the current-voltage and on-off ratio of transistor were investigated. And, we also studied the surface morphology of C60 layer under various deposition rate with AFM. The vertical type organic transistor using C60 exhibited low operation voltage compared to the case of F16CuPc. Additionally, the light emitting transistor using the vertical type transistor and P3HT as a light emitting polymer was investigated. [ABSTRACT FROM AUTHOR]