• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1575-1577
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• 2002

In this study, multi layer type OLED(Organic Light Emitting Diode) has been fabricated using $Snq_2$, $Snq_4$, and $Alq_3$ for development of high efficiency, electrical and optical properties of multi layer type OLED investigated. The HTL(Hole Transfer Layer) and EML(Emitting Material Layer) were fabricated by using vacuum evaporation on ITO electrode, and its thickness controlled using thickness monitor. Al was used as a cathode. The electrical and optical properties such as J-V, brightness-V and EL spectrum of OLED device was measured using I.V.L.T system. The result, brightness of $Alq_3$, $Snq_2$ and $Snq_4$ were $3900cd/m^2$, $63cd/m^2$ and $23cd/m^2$ respectively.

• Journal of Surface Science and Engineering
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• v.44 no.6
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• pp.239-245
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• 2011

Magnesium alloys is the lightest by structural metals, but it is not good corrosion resistant because of pit, void. Particularly, AZ31B magnesium alloy sheets that have slag, scratch by rolling process indicate some defects. The objective of this research is to perform uniform plating on AZ31B by studying etching and zincate process. Especially, zincate treatment by zinc salt and pyrophosphate is the most important in the decoration plating. Dissolution of magnesium is reduced by the formation of uniform zinc conversion layer during strick and post process, which decreases defects for plating process.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.164-167
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• 1997

The treatment setup of patients during irradiation is an important aspect in relation to the success of radiotherapy. Imaging with the treatment beam is a widely used method or verification of the radiation field position relative to the target area, prior to or during irradiation. In this paper, Real time digital radiography system was implemented or verification of local error between simulation plan and radiation therapy machine. Portal image can be acquired by CCD camera, image board and pentium PC after therapy Radiation was converted into light by a metal/fluorescent Screen. The resulting image quality is comparable to film, so the imaging system represents a promising alternative to film as a method of verifying patient positioning in radiotherapy. Edge detection and field size measurement were also implemented and detected automatically for verification of treatment position. Field edge was added to the original image or checking the anatomical treatment verification by therapy technicians. By means of therapy efficiency improvement and decrease of Radiation side effects with these techniques, Exact Radiation treatments are expected.

• Journal of Power System Engineering
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• v.3 no.3
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• pp.70-75
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• 1999

This study is for the development of tie rod end, a parts of steering system, that would be changed with plastic material. The position of weld line is founded by the analysis of Mold Flow, computer software with FEM(Finite Element Method). Then new mold is designed by consideration with the locations of weld line. PA66(G/F 35%), PA6(G/F 45%), PET(G/F 45%) and PET(G/F 55%) are tested two types loading conditions for selecting suitable material, the requirement tensile load(more 19600N). PA6(G/F 45%) showed high mechanical properties in this study. And then, tensile strength was compared between conventional metal products and the injection molded products which were reinforced with 33%, 34%, 45%. 60% of glass fiber in matrix material. In the case of, the measured two types of tensile load values are 24500N (Method-1), 21560N (Method-2) and weight is decreased by 50% of conventional one.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.381-386
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• 2006

Many different types of bleaching chemicals and processes have been globally used for deinked pulp. Besides chlorine-free bleaching chemicals, hydrogen peroxide, and sodium dithionite that could be used without restriction for almost all types of fibers, chlorine-containing chemicals such as chlorine dioxide and sodium hypochlorite have also used throughout the world. Even though hydrogen peroxide is commonly used in newsprint, it could not effectively increase brightness. Experimental evaluation on the possibility of using formamidine sulfinic acid (FAS), a reducing agent, for bleaching a wood-containing deinked pulp has been carried out in this study. The effect of bleaching efficiency for FAS on operational conditions and chemical concentrations compaired to hydrogen peroxide in one and two stages was studied. FAS bleaching showed higher brightness at high temperature and low consistency, and vice versa for peroxide one. Bleaching with sodium silicate and DTPA in FAS and peroxide stage showed better results than cases without them. Sodium silicate and chelant seemed minimize the influence of transition metal ions, including manganese and iron ions, which induce both bleaching agents to decompose. As a result, FAS as a reducing agent seems more effective than hydrogen peroxide for increasing brightness and reducing yellowness. FAS and FAS sequence seemed more efficient than the other two stages of bleaching sequences with regard to the best brightness level obtained. When bleaching was conducted with FAS, COD load was just about one-third compared to peroxide, and brightness stability of the bleached pulp appeared better than peroxide after UV light irradiation.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.336-336
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• 2011

Over the past decades, organic semiconductors have been investigated intensely for their potential in a wide range of optoelectronic device applications since the organic materials have advantages for very light, flexible and low cost device fabrications. In this study, we fabricated small-molecule organic solar cells (OSCs) based on chloro[subphthalocyaninato]boron(III) (SubPc) as an electron donor and $C_{60}$ as an electron acceptor material. Recently SubPc, a cone-shaped molecule with $14{\pi}$-electrons in its aromatic system, has attracted growing attention in small-molecule OSC applications as an electron-donating material for its greater open-circuit voltage (VOC), extinction coefficient and dielectric constant compared to conventional planar metal phthalocyanines. In spite of the power conversion efficiency (PCE) enhancement of small-molecule OSC using SubPc and $C_{60}$, however, the study on the interface between donor-acceptor heterojunction of this system is limited. In this work, SubPc thin films at various thicknesses were deposited by organic molecular beam deposition (OMBD) and the evolution of surface morphology was observed using atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM). We also investigated the influence of film thickness and surface morphology on the PCE of small-molecule OSC devices.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.376-376
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• 2011

I-III-VI2 chalcopyrite compounds, particularly copper, indium, gallium selenide(Cu(InxGa1-x)Se2, CIGS), are effective light-absorbing materials in thin-film solar application. They are direct band-gap semiconductors with correspondingly high optical absorption coefficients. Also they are stable under long-term excitation. CIS (CIGS) solar cell reached conversion efficiencies as high as 19.5%. Several methods to prepare CIS (CIGS) absorber films have been reported, such as co-evaporation, sputtering, selenization, and electrodeposition. Until now, co-evaporation is the most successful technique for the preparation of CIS (CIGS) in terms of solar efficiency, but it seems difficult to scale up. CIS solar cells have been hindered by high costs associated with a fabrication process. Therefore, inorganic colloidal ink suitable for a scalable coating process could be a key step in the development of low-cost solar cells. Here, we will present the preparation of CIS photo absorption layer by a solution process using novel metal precursors. Chalcopyrite copper indium diselenide (CuInSe2) nanocrystals ranging from 5 to 20nm in diameter were synthesized by arrested precipitation in solution. For the fabrication of CIS photo absorption layer, the CuInSe2 colloidal ink was prepared by dispersing in organic solvent and used to drop-casting on molybdenum substrate. We have characterized the nanoparticless and CIS layer by XRD, SEM, TEM, and ICP.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.109-113
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• 1994

Effects of various formulation factors using $L_8$ orthogonal arrays with the stability of doxorubicin hydrochloride injections(DHls) were investigated. The degradation of DHI may be occured by pH, temperature, light and metal ions. It is known that DHI should be stored on refrigerated condition of $4{\sim}8^{\circ}C$ because of its unstability on the room temperature. The employed factors were sodium chloride as isotonic solution, sodium bisulfite or sodium pyrosulfite as an antioxidant, disodium edetate as a chelating agent, methyl parahydroxybenzoate as a dissolution time shortening agent, and hydrochloric acid or citric acid as a pH adjusting agent at $22^{\circ}C$. From the results of $L_8$ orthogonal arrays, an optimal formula, including sodium chloride, disodium edetate, sodium bisulfite and hydrochloric acid, was obtained and the shelf-life of the formula was determined as 560 days approximately.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.101-111
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• 1999

Sedimentary organic matter, exposed to continental surficial environment, reacts with oxygen supplied from the atmosphee and forms carbon-containing oxidation products. Knowledge of the rate and mechanisms of sedimentary organic matter weathering is important because it is one of the major controls on atmospheric oxygen level through geologic time. Under the abiological conditions, the oxidation rate of coal organic matter by molecular oxygen is enhanced by the increase of oxygen concentration and temperature. At ambient temperature and pressure, aqueous coal oxidation results in the formation of dissolved $CO_2$ dissolved organic carbon and solid oxidation products which are all quantitatively significant reaction products. The effects of pH, ultraviolet light, and microbial activity on the weathering of sedimentary organic matter are poorly contrained. Based on the results of geochmical and environmental studies, it is believed that the photochemical reaction should play an important role in the decomposition and oxidation of sedimentary organic matter removed from the weathering profile. At higher pH conditions, the production rate of DOC can be accelerated due to base catalysis. These high molecular weight oranic matter can react with man-made pollutants such as heavy metal ions via adsorption/desorption or ion exchange reactions. The effect of microbial activity on the oxidative weathering of sedimentary organic matter is poorly understood and remains to be studied.

• Journal of Fashion Business
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• v.20 no.2
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• pp.78-96
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• 2016

This study investigated the colors of the costumes and backgrounds of characters in the fantasy film, Alice in Wonderland(2010) by Tim Burton. The methods used were literature studies including related books, articles and internet materials, and positive research with DVD color analysis. Twenty-one scenes were selected by the researcher. Five scenes were selected from novel and film components representing, exposition, complication, crisis, climax, and denouement. After controlled pixel by photoshop program and the represented colors, hues and tones were analyzed. The results were as follows; First, in four characters, Alice's dress colors changed depend on the situation and the passage offered from blue to red, metal light, and blue green. The Mad Hatter's colors were orange with green which signified madness and passion. The Red Queen's red dress and blue make up represented countrified and evil. The White Queen's all white dress and hair, black eyes and vivid red meant purity and nobility. Similar characters' colors were limited. Second, the background colors, especially tones were an important component of the fantasy image. These were different for each type of scene in the film such as exposition, complication, crisis, climax, and denouement.