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Although polyethylene (PE) is one of the most frequently used synthetic polymers in the plastics market, it is very difficult to imprint or bond PE with adhesives without pre-treatments based upon electrical, chemical and thermal processes. This is because a uniform adhesion property of PE cannot be expected without these processes. In this study, we suggest a simple, fast and cost-effective method to improve the adhesion properties of PE using a Kapton tape, which is a polyimide film generally used in flexible electronics. Specifically, by wrapping PE substrates applied with an adhesive using a Kapton tape and curing the sample using either a hot-press or a hot plate, the standard deviation of the shear strength decreased by 82.1% and 87.6%, respectively. To further improve the adhesion of PE substrates, we functionalized their surface using coupling agents, such as (3-glycidoxypropyl) methyldiethoxysilane and (3-aminopropyl) trimethoxysilane after an ultraviolet-ozone process. Using X-ray photoelectron spectroscopy and vacuum Fourier-transform infrared spectroscopy analysis, we proved that a significant improvement in the adhesion of PE occurred because of chemical crosslinking between either epoxy or amine groups functionalized on the PE substrates and epoxy-based adhesives comprising diglycidyl ether epoxy resin and triethylenetetramine hardener. This study is important, as it suggests a simple and very effective method to obtain highly reliable adhesion properties of PE using conventional adhesives.

This article presents the hybrid design and control of a quad-rotor system called Flymobile. Flymobile is a combined system of a mobile robot and a quad-rotor system aimed to perform both flying and driving tasks. Flymobile performs flying tasks in the same way as conventional quad-rotor systems while the tilting mechanism of each rotor allows Flymobile to navigate in its terrain for a driving task. The body frame with rotors is implemented by a calibration process through a test-bed equipped with a force sensor. The triangular wheel frame is designed to mimic motions of a mobile robot with three passive wheels. Sensor data of a gyro and an accelerometer are filtered and used for controlling the attitude of the system. Focusing on a practical approach of implementing a hybrid system, a non model-based approach is applied to control Flymobile. Experimental studies are demonstrated to show the feasibility of performing both driving and flying missions.

In-vessel components of the Korea Superconducting Tokamak Advanced Research (KSTAR) were developed for 2010 campaign to provide a crucial circumstance for achieving the strongly shaped and diverted plasma. Moreover, the in-vessel components such as limiter, divertor, passive stabilizer, in-vessel control coil (IVCC) system demonstrated good performances satisfying the original design concepts. In addition to the plasma facing components and the IVCC, in-vessel cryo-pump (IVCP) system was also installed to leverage divertor operation. Besides the in-vessel components, there have been substantial progresses in development of the heating and current drive system. The KSTAR heating and current drive system includes all kinds of the major heating systems such as neutral beam injection (NBI), ion cyclotron range of frequency (ICRF), electron cyclotron resonance heating and current drive (ECH and ECCD), lower hybrid current drive (LHCD) systems. As an initial stage for full equipment of the heating systems to total power of 26 MW, several key systems such as 1st NBI (called NBI-1), ICRF, and ECH-assisted startup system successfully demonstrated their excellent feasibilities in the design and performances for dedication to the 2010 campaign.

Electrodialysis (ED) is one of a number of attractive options in the desalination of secondary effluent, but membrane fouling is still an issue that needs to be resolved. This study investigated potential foulants and the fouling control of ED during desalination. Cation and anion exchange membranes were found to be fouled with different components in secondary effluent. Protein and calcium ion were the most responsible for the fouling of anion and cation exchange membranes, respectively. Pretreatment using iron oxide particles (IOPs) as an adsorbent contributed greatly to the reduction of irreversible fouling caused by organic matter present in the secondary effluent. IOP pretreatment also improved the quality of the treated water significantly.

Metal doped ZnO (MZO, metal = Al, Ag, Li) films were deposited by RF magnetron sputtering system. We investigated the physical properties and the etching characteristics of the MZO films. All MZO films have shown a preferred orientation in the [001] direction. As amounts and a kind of dopant in the target were changed, the crystallinity and the transmittance as well as the optical band gap were changed. The electrical resistivity was also changed according to the metal doping amounts and a kind of dopant. The chemical dry etching of as-grown MZO thin films was investigated by varying gas mixing ratio of CH4/(CH4 + H2 + Ar) and additive Cl2 chemistries. We could effectively etch not only a zinc oxide but also metal dopant using methane, hydrogen, argon, as well as chlorine gas. Changes of the structural, optical electrical properties, etch rate, and chemical states of etched surface for the MZO films were also explained with the data obtained by SEM, XRD, UV, 4-point-probe and XPS analyses.

We deposited ZnO thin films at room temperature by RF magnetron sputtering method with home-made targets, and for application tests using these films as transparent conductive oxide (TCO) anodes, wet-chemical etching behaviors of ZnO films were also investigated using various chemicals. In order to fabricate ZnO-based OLED devices, various etchants such as HCl, HNO3, H2SO4 and H3PO4 have been studies for the wet etching of ZnO thin film. In this experiment, we introduced two new different chemicals as etchants, ferric chloride (FeCl3 ∙ 6H2O) and oxalic acid (C2H2O4) which were controlled with various concentrations in ZnO etching process and showed an anisotropy etching shape of ZnO films.

Zinc oxide (ZnO) is an excellent piezoelectric material with simple composition. ZnO film is applied to the piezoelectric devices because it has high resistivity and highly oriented direction at c-axis. Structural and electrical properties in ZnO films are influenced by deposition conditions. Lithium-doped ZnO (LZO) films were deposited by RF magnetron sputtering method using Li-doped ZnO ceramic target with various ratios (0 to 10 wt.% LiCl dopant). LZO films revealed high resistivity of above 10 7 Ω cm with smooth surface when they were deposited with 4% LiCl-doped ZnO target under room temperature. However, their c-axis orientation was worse than the c-axis orientation of pure ZnO films. We have also studied on structural, optical and electrical properties of the ZnO films by XRD, AFM, SEM, XPS, and 4-point probe analyses. We concluded that LZO films were deposited with 4 wt.% LiCl-doped ZnO target and were apposite for piezoelectrical application.

The metal doped ZnO (MZO, M=Al, Ag) films were prepared by RF magnetron sputtering on glass substrates with extraordinary designed the MZO targets. For the doping sources contained in each MZO target, we used Al(OH)3, AgNO3 powders by mixing the powders into pure ZnO powder with various rate (0–10 wt.%), respectively. We investigated on the optical and electrical properties of the as-sputtered MZO films as dependences of the dopant contents in targets. All the MZO films had shown a preferred orientation in the [001] direction. As the quantity and variety of metal dopants were changed, the crystallinity and the transmittance as well as optical band gap were changed. The electrical resistivity was also changed with changing metal doping amounts and a kind of dopant. To investigate these phenomena in details, the O K-edge configurations of the MZO films were studied.

Plasma polymerized organic thin films have been deposited on Si(100), glass and metal substrates at 25¨100 -C using thiophene and toluene precursors by plasma enhanced CVD method. In order to compare physical and electrochemical properties of the as-grown thin films, the effect of the RF (13.56 MHz) plasma power in the range of 30¨100 W and the deposition temperature on the corrosion protection efficiency and optical property were mainly studied in this work. Corrosion protection efficiency (Pk), which is one of important factors for corrosion protection in the interlayer dielectrics of microelectronic devices application, provided an increasing tendency with increasing RF power. The highest Pk value of plasma polymerized toluene film (85.27% at 70 W) was higher than that of the plasma polymerized thiophene film (65.17% at 100 W). The result of contact angle measurement showed that the plasma polymerized toluene films have more hydrophobicity than that of the plasma polymerized thiophene films. D 2005 Elsevier B.V. All rights reserved.

We successfully deposited the reliable silicate/HfO 2 insulator films on both p-Si/Si 0 . 8 Ge 0 2 and p-Si/Si 0 . 8 Ge 0 . 2 /intrinsic-Si substrates via the oxidation and annealing of thin Hf film deposited by rf-magnetron sputtering. The oxidation of Hf metal films results in the electrically stable silicate/HfO 2 stacked layers. The silicate films (i.e., a layer of Hf-Si-Ge-O) were formed between the HfO 2 film and the p-Si/ Si 0 . 8 Ge 0 . 2 substrate. We found that the Ge segregation is suppressed by the insertion of a 2-nm-thick Si-overlayer on the Si 0 . 8 Ge 0 . 2 substrate, resulting in better electrical properties than those obtained from the samples without the Si-overlayer. High-temperature annealing at 700 °C causes the diffusion of Ge into the silicate/HfO 2 stacked insulator films only for the samples without the Si-overlayer. In addition, 700 °C annealing results in the formation of a thin SiO x layer at the silicate-Si 0 . 8 Ge 0 . 2 substrate regardless of the presence of the Si-overlayer.

Silver-doped ZnO (SZO) films were prepared by rf magnetron sputtering on glass substrates with specially designed ZnO target. For the doping source for target, we use AgNO3 powder with a various mixing ratio (0, 2, and 4 wt.%). We investigated a dependency of coating parameter, such as dopant content, in target and substrate temperature on structural and optical properties of the as-grown SZO films. The SZO films have a preferred orientation in the (002) direction. As amounts of the Ag dopant in the target were increased, the crystallinity as well as the transmittance and optical band gap were decreased while those properties were degenerated at 200 8C. And as the substrate temperature was increased, the crystallinity and the transmittance were increased. In details, changes of optical band gap for the SZO films were explained with the data obtained by XRD, XPS and using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. D 2004 Elsevier B.V. All rights reserved.

We investigated the effects of both bottom electrodes and processing parameters on the physical and electrical properties of ZnO films deposited by R.F. magnetron sputtering. We found that the preferential c-axis growth of deposited ZnO films depends on the type of bottom electrode: Both Al and Au bottom electrodes enhance the growth of c-axis orientation in ZnO films, while no clear evidence for any preferential growth was observed in case of Cu and Si. The resistivity of ZnO films deposited on Au and Al bottom electrodes was greater than 10 6 V cm. The ranges of dielectric constant of Al/ZnO and Au/ZnO samples were 8–14 and 13–16, respectively. Dissipation factors change from 0.02 to 0.05. In general, as c-axis orientation enhances, dielectric constant and dissipation factor increase and decrease, respectively.

Thin films of ZrO2 were deposited on p-Si(100) substrates using RF magnetron sputtering technique. To investigate the influence of the sputtering parameters, e.g., annealing temperature, different O2-flux, RF power and target to substrate distance on the physical and electrical properties of the as-grown films, systematic investigation using X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscope and energy dispersive X-ray (SEM–EDX), C–V, and I–V were carried out in this work. Deposited ZrO2 films had polycrystalline after annealing sample at high temperature. Their silicon oxide (SiO2) layers were formed between high-k film (i.e., ZrO2 and YSZ) and Si substrate either after annealing samples at high temperature or introducing O2-flux the sputtering process step. The high-k thin films have to be deposited amorphous structure without SiO2 interlayers. We also investigated the electrical properties of both the a-ZrO2 and a-YSZ films prepared without O2-flux at room temperature with conditions of various RF power and target to substrate distance. The dielectric constant of amorphous YSZ was determined to be about 24 using metal–insulator– semiconductor (MIS) capacitor structure. The smallest leakage current density of the YSZ film grown at 150 W and at room temperature was obtained to be about 10 10 at 1 V. D 2004 Elsevier B.V. All rights reserved.

Transparent conductive aluminum-doped ZnO (AZO) films were prepared by RF magnetron sputtering on glass substrates with specifically designed ZnO target using high-purity of zinc oxide (99.99%) and aluminum hydroxide (99.99%) powders. Systematic study on dependence of target-to-substrate distance (D ) on structural, electrical and optical properties of the as-grown AZO ts films was mainly investigated in this work. XRD shows that highly preferred AZO crystal in the w001x direction was grown in parallel to the substrate while the D doesnot effected to the peak position of XRD. With decreasing D the growth rate is ts ts increased while the electrical resistivity as well as crystal size in the AZO films is decreased. The XPS data show that zinc has remained with nearly oxidation state and has been attributed to the presence of excess zinc in the films. The O yZn ratio in AZO films was increased with increasing D in the films. The as-grown AZO films have an average transmittance of above 85% at ts the visible region. The optical band gap of the as-grown AZO films was changed from 3.18 to 3.36 eV with D . The resistivity ts

Highly oriented undoped and aluminum-doped ZnO (AZO) films in the (002) direction were prepared by RF magnetron sputtering on glass substrates with specifically designed ZnO targets containing different amounts of Al(OH)3 powder as doping source. A systematic study of the influence of deposition parameters such as Al(OH)3 content in the target, the target–substrate distance (Dts), deposition time and substrate temperature on the structural, electrical and optical properties of the as-grown AZO films was carried out. XRD shows that AZO (002) crystal grew parallel to the substrate. With increasing Dts the growth rate increased, while the substrate temperature did not affect the growth rate. The as-grown AZO films not only have an average transmittance of >85% in the visible region, but also have an optical bandgap between 3.2 and 3.64 eV, depending on the sputtering parameters. The resistivity of the film deposited at Dts=45 mm from a 4 wt.% Al(OH)3-doped ZnO target was approximately 9.8×10−2 Ω cm, showing semiconductor properties.

In this paper, we propose a fast skew estimation and correction algorithm for English and Korean documents based on a BAG (Block Adjacency Graph) representation. BAG is one of the most efficient data structures for extracting various information concerning connected components; the image rotation for skew correction is performed rapidly using the block information in the BAG. The proposed skew estimation algorithm uses a coarse/refine strategy based on the Hough transformation of connected components in the image. The skew correction algorithm then generates a non-skew image by rotating the blocks, rather than the individual pixels. An experiment using 2016 images from various English and Korean documents demonstrates how the proposed method is superior to conventional ones.

In an effort to ameliorate generic concerns with current power reactors such as the risk of proliferation, radiological hazard of the spent fuel, and the vulnerability to core-melt accidents, the concept of a revolutionary reactor, named PEACER, has been developed as a proliferation-resistant waste transmutation reactor based on the unique combination of technologies of a proven fast reactor and the heavy liquid metal coolant. In this paper, results of the PEACER conceptual design are presented by focusing on the estimated performance of the PEACER system. The proliferation resistance of PEACER is based upon both institutional and technical issues. The latter includes denaturing of fissile materials, Pu in particular, as well as the intense radiation field associated with the pyrochemical partitioning method. When the fuel volume fraction and the core aspect ratio( L D ) are optimized, the transmutation capability of PEACER for long-lived wastes from LWR spent fuels is found to exceed the production rate of two LWR's with the same electric rating. In contrast with current power reactor design principles, the lower power density and the higher neutron leakage rate lead to higher performance with respect to proliferation-resistance, transmutation capability and the accident-tolerance. Results of the present conceptual design show promising characteristics in all the five targets proposed by its name PEACER, which warrants more detailed study.

Application of autoregressive (AR) modeling in study of the results of proper orthogonal decomposition (POD) of wind-induced pressure on a low-rise building is described in the paper. The POD principal coordinates (PC) were obtained for point pressure measured simultaneously at 495 taps on the surface of a model of a low-rise building. The AR models were next fitted for the first four PC, and they were compared with the AR models developed for point pressure at representative taps on the building windward wall and roof. It was found that the order of the AR required for the principal coordinates was relatively low, and it did not exceed the order of the AR established for the considered point pressure.