A new image segmentation technique based on partition mode test

Image segmentation is one of the most important steps in a modern computerized machine vision system. This paper describes a simple, systematic one-pass image segmentation algorithm which is based on the partition mode test of pixels within a (2 × 2) window and assigning and updating label fields to the pixels of this window. A number of well chosen examples are shown to demonstrate the capabilities of the new algorithm.     

Synthesis of highly conducting nylon-6 composites and their electrical properties

Highly conducting nylon-6 composites are synthesized by exposing nylon-6 films or fabrics impregnated with an oxidizing agent, cupric chloride, simultaneously to aniline and hydrochloric acid vapors. The conductivity of composite films reaches up to 10^?2 S/cm and can be controlled by varying the experimental conditions for the composite synthesis. The effects of the concentration of cupric chloride, exposure time to aniline and hydrochloric acid vapors, and concentration of hydrochloric acid to the polyaniline content and the conductivity of nylon-6/polyaniline composites are analyzed by means of statistical F test. The morphology change of composite films resulting from the synthesis conditions, conductivity in relation to the morphology, and stability of conductivity to ambient air exposure have been investigated.     

Expected service time model for a rotary parking system

This paper deals with rotary parking system. For retrieval and storage request, an expected service time model is developed based on the continuous Markov process. The validity of the model is illustrated through simulation studies.     

Synthesis and properties of copolymers composed of arylenevinylene and phenothiazine for organic solar cells

A series of new organic semiconducting copolymers composed of {(2E,2'E)-3,3'-[2,5-bis(octyloxy)-1,4-phenylene]-bis[2-(thiophen-2-yl)acrylonitrile]}(OPTAN) and 10(2'-ethylhexylphenothiazine) (PTZ) monomers, (the copolymers are hereafter referred to as poly(OPTAN-co-PTZ)s), were synthesized by using Suzuki coupling polymerization in which the monomer ratios were controlled. An increase in the OPTAN content shifted the peak and onset absorption of the copolymers to the longer wavelength regions, which resulted in a decrease in the band gap energy. The maximum UV absorption of the polymer films was in the range 523-540 nm and the optical band gap energies were in the range 1.90-1.87 eV. Energy levels of the highest occupied molecular orbital (HOMO) of the polymers were determined by cyclic voltammetry (CV). The HOMO energy level of the copolymers was between -5.07 and -5.12 eV. Photovoltaic devices were fabricated by using the copolymers as the p-type donor and C60-PCBM or C70-PCBM as the electron acceptors. The device with poly(50OPTAN-alt-50PTZ) and C70-PCBM showed the best performance among the fabricated devices; the open circuit voltage, short circuit current, fill factor, and maximum power conversion efficiency of this device were 0.79 V, 5.25 mA/cm2, 0.30, and 1.25%, respectively.     

Synthesis and photovoltaic property of fine and uniform Zn2SnO4 nanoparticles

Zn(2)SnO(4) nanoparticles (NPs) with a narrow size distribution were synthesized by a simple hydrothermal route by controlling the crystallization process. The average size of NPs was 8 nm, and this was attributed to the formation of a hydroxy carbonate compound as an intermediate phase, which was demonstrated by the structural and elemental analyses. The fine size and visible-transparency of the synthesized NPs enabled the fabrication of transparent films for efficient photoelectrochemical devices. In particular, we demonstrated dye-sensitized solar cells (DSSCs) employing these transparent Zn(2)SnO(4) photoelectrodes with a high energy conversion efficiency of 4.7%, which is mainly due to an improvement of light harvesting property.     

Metabolite profiling of doenjang,fermented soybean paste,during fermentation

BACKGROUND: A fermented soybean paste known as doenjang is a traditional fermented food that is widely consumed in Korea. The quality of doenjang varies considerably by its basic ingredients, species of microflora, and fermentation process. The classification of predefined metabolites (e.g. amino acids, organic acids, sugars and sugar derivatives, and fatty acids) in doenjang samples according to fermentation was performed by using GC‐FID and GC‐MS data sets with the application of a multivariate statistical method. RESULTS: The predominantly produced amino acids included alanine, valine, leucine, isoleucine, proline, glutamine, phenylalanine and lysine, showing remarkable increases in amounts during the later stages of fermentation. Carbonic acid, citric acid, lactic acid and pyrogultamic acid were identified as the major organic acids. Significant amounts of erythrose, xylitol, inositol and mannitol were detected during fermentation. Regarding fatty acids, relatively higher amounts of palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid were found in the doenjang at each fermentation time point. Principal component analysis (PCA) successfully demonstrated changes in composition patterns as well as differences in non‐volatile metabolites according to fermentation period. CONCLUSION: A set of metabolites could be determined representing the quality of doenjang during fermentation, and which might also be correlated with taste ingredients, flavour, nutrition, and physiology activities that are claimed to be dependent on the quality control of commercial doenjang. Copyright © 2010 Society of Chemical Industry     

Preparation of highly dispersed tungsten oxide on MCM-41 via atomic layer deposition and its application to butanol dehydration

Highly dispersed tungsten oxide on MCM-41 was synthesized using a novel atomic layer deposition (ALD) method. BET, XRD, XPS, NH3-TPD, and pyridine-IR were used to study the physicochemical properties of the supported tungsten oxides. In this study, the maximum loading of tungsten oxide on MCM-41 that could be prepared using the modified ALD method was 27.0 wt%. It was confirmed that the textural properties of the mesoporous silica were maintained after tungsten oxide loading. The NH3-TPD and Py-IR results indicated that weak acid sites, mainly Lewis acid sites, were produced over the WO3/MCM-41 samples. Moreover, 2-butanol dehydration was performed to demonstrate the potential advantages of the WO3/MCM-41 catalysts. The WO3/MCM-41 catalyst with 27.0 wt% tungsten oxide loading showed the highest activity in the dehydration of 2-butanol, which was attributed to the highest overall number of acid sites among the WO3/MCM-41 catalysts. The highly dispersed tungsten oxide on MCM-41 prepared via ALD can be an effective catalyst for producing butenes through 2-butanol dehydration.     

Modified polyvinyl alcohol layer with hydrophobic surface for the passivation of pentacene thin-film transistor

We modified the surface of a polyvinyl alcohol (PVA) layer by self assembly monolayer technique using a fluorine substituted silane compound (1H,1H,2H,2H-perfluorooctyl-trichlorosilane: FTS) to protect a pentacene thin-film transistor (TFT) from O2 and H2O. Surface modified PVA showed very low surface energy with water contact angle of 106.2 degrees. Surface treatment of PVA layer on pentacene TFT device was done in toluene solvent and we did not observe any damage to the PVA layer or pentacene TFT devices during surface modification process. Pentacene TFT with surface modified PVA passivation layer exhibited very stable TFT operation with almost no field effect mobility drop or threshold voltage shift up to 400 hrs. The performance of unpassivated OTFTs exponentially degraded and almost failed in 290 hrs. We propose that modified PVA layer can be used as a good passivation layer for oxygen and water in OTFT.     

Synthesis and characterization of conjugated low band-gap terpolymers incorporating carbazole for photovoltaic application

A series of photoactive conjugated low band-gap copolymer (CPSB) and terpolyemrs (TPSBCz-n, n = 1 to 4) based on N-alkyl carbazole, 4,4'-dialkyl dithienosilole, and bezothiadiazole were synthesized. The copolymer and terpolymers were built with the fraction of the carbazole unit varied for 0, 2.5, 5, 10 and 25 mol%. Among the mixtures, the composition of 25 wt% of terpolymer bearing 10 mol.% of the carbazole unit, TPSBCz-3, and 75 wt% of C71-PCBM found a power conversion efficiency of 0.86% with a open-circuit voltage of 0.59 V, the short-circuit current of 4.85 mA and fill factor of 0.30 under AM 1.5 spectral illumination. Our findings suggest that terpolymer bearing low concentration of carbazole lead to a high power conversion efficiency with improved the short-circuit current due to hole mobility enhancement effect of carbazole unit.