• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.725-730
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• 1996

The key process in silicon surface micromachining is the selective etching of a sacrificial layer to release the silicon microstructure. The newly developed anhydrous HF/$CH_3$OH gas phase etching of TEOS (teraethylorthosilicate) sacrificial layers onto the polysilicon and the nitride substrates was employed to release the polysilicon microstructures. A residual product after TEOS etching onto the nitride substrate was observed on the surface, since a SiOxNy layer is formed on the TEOS/nitride interface. The polysilicon microstructures are stuck to the underlying substrate because SiOxNy layer does not vaporize. We found that the only sacrificial etching without any residual product and stiction is TEOS etching onto the polysilicon substrate.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.341-344
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• 2008

Plastics is commonly used in consumer electronics because of it is high strength per unit mass and good productivity. But. using, transporting, and keeping of plastic component was happened post-deformation. As time goes by and temperature is changed, the post-deformation causes the problems of exterior design and performance. But, it is difficult to estimate the post-deformation by only thermal deformation analysis. Also, the estimation technique of the pest-deformation must be easily applied to product development and it should be reliable because development time of product is limited. In the paper. the process to predict the post deformation under cyclic thermal loadings was suggested. The process was applied to the real panel, and the deformation predicted by the analysis was compared with that of real test, which showed the possibility of applying the suggested process to predict the post deformation of plastic product under thermal loadings.

• Korean Journal of Oriental Medicine
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• v.14 no.1
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• pp.49-58
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• 2008

Objective : To provide information about the accessory product of Broussonetia kazinoki Siebold or Broussonetia papyrifera (L.) Vent by analyzing old books of oriental medicine, domestic/international papers and related patents Methods : Old books related to the accessory product in the field of oriental medicine were reviewed. Research papers regarding the pharmacological activity of the by-products were reviewed and analyzed. Patents about the residual products were examined and classified by year and subject Results : Seven kinds of by-products from Broussonetia kazinoki Siebold or Broussonetia papyrifera (L.) Vent has been used as medicines in oriental medicine. Recently, anti-oxidating, anti-cancer, anti-mutagenic and anti-inflammation activity of the residual product of these plants has been investigated through scientific research. There were 19 patents related with the accessory products of these plants, which were in the subjects of functional cosmetics, anti-inflammation, cleansing goods, hair restorers or improvement of learning ability. Further investigations about the activity of these plants are needed in bone metabolism, water balance and hemostasis in the future. Conclusion : Residual products from these plants is being used in various ways. However, more studies on the efficacy and mechanism, as well as safety, of these plants should be conducted precisely in the future.

• Korean Journal of Materials Research
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• v.23 no.1
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• pp.18-23
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• 2013

In this study, the effects of cryogenic treatment cycles on the residual stress and mechanical properties of 7075 aluminum alloy (Al7075) samples, in the form of a tube-shaped product with a diameter of 500 nm, were investigated. Samples were first subjected to solution treatment at $470^{\circ}C$, followed by cryogenic treatment and aging treatment. The residual stress and mechanical properties of the samples were systematically characterized. Residual stress was measured with a cutting method using strain gauges attached on the surface of the samples; in addition, tensile strength and Vickers hardness tests were performed. The detailed microstructure of the samples was investigated by transmission electron microscopy. Results showed that samples with 85 % relief in residual stress and 8% increase in tensile strength were achieved after undergoing three cycles of cryogenic treatments; this is in contrast to the samples processed by conventional solution treatment and natural aging (T4). The major reasons for the smaller residual stress and relatively high tensile strength for the samples fabricated by cryogenic treatment are the formation of very small-sized precipitates and the relaxation of residual stress during the low temperature process in uphill quenching. In addition, samples subjected to three cycles of cryogenic treatment demonstrated much lower residual stress than, and similar tensile strength compared to, those samples subjected to one cycle of cryogenic treatment or artificial aging treatment.

• Journal of the Semiconductor & Display Technology
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• v.20 no.4
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• pp.49-54
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• 2021

The display industry is transitioning from traditional rigid products such as flat panel displays to flexible or wearable ones designed to be folded or rolled. Accordingly, colorless and optically transparent polyimide (CPI) films are one of the prime candidates to substitute traditional cover glass as a passivation layer to accommodate product flexibility. However, CPI films subjected to repetitive pure bending loads inevitably entail an accumulation of residual strain that can eventually cause wrinkles or delamination in the underlying component after a certain number of static and cyclic loading. The purpose of this study is to establish an experimental method to systematically evaluate the bending residual strain of CPI films. Films were monotonically and cyclically wrapped on mandrels of various diameters to ensure a constant strain in each. After unwrapping the wound CPI film, the residual radius of curvature remaining on the film was measured and converted into residual strain. The critical radius of curvature at which residual strain does not remain was about 5 mm, and the residual strain decreased in proportion to the log time. It is expected that flexible displays can be reliably designed using the data between the applied bending strain and the residual strain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.635-640
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• 2001

These studies were carried out to develop sausage using extracts from waste resources. The changes of pH and moisture contents were tended to be a similar to control, respectively ranged in pH 6.0~6.4 and 62~60% in moisture content. However, the water holding capacity of sausage added with chitosan and sesamol gradually were tended to be a little high, compared to control. The treatments using natural resource by-product revealed a low TBARS value, compared to control. This means that sausage added with natural by-product seem to be extend its shelf-life during storage. At the same time, the TBARS values were very similar to sausage added with 0.5% potassium sorbate. The residual nitrite contents of sausage added with natural resource by-product were tended to be a little lower than that of control. As storage time goes by, the nitrite contents of sausage product gradually were a little more decreased during storage at 3$0^{\circ}C$ than those of storage at 1$0^{\circ}C$. The lightness of sausage color gradually were a little more decreased during storage at 3$0^{\circ}C$ than those of storage at 1$0^{\circ}C$. The redness of sausage added with chitosan were a little highter, compared to control Sensory test suggested that the changes of sausage color, flavor, texture and taste were tended to be decreased gradually. In conclusion, sausage added with natural resource by-product was effective on the basis of the reduction in residual nitrite content and lipid oxidation.

• Journal of Adhesion and Interface
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• v.4 no.2
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• pp.1-9
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• 2003

Epoxy-amine liquid prepolymers are extensively applied onto metallic substrates and cured to obtain painted materials or bonded joint structures. Overall performances of such systems depend on the created interphase between the organic layer and the substrate. When epoxy-amine liquid mixtures are applied onto more or less hydrated metallic oxide layer, concomitant amine chemical sorption and hydroxide dissolution appear lending to the chelate formation. As soon as the chelate concentration is higher than the solubility product, these species crystallize as sharp needles. Moreover, intrinsic and thermal residual stresses are developed within painted or bonded systems. When residual stresses are higher than the organic layer/substrate adhesion, buckling, blistering, debonding may occur leading to a catastrophic drop of system performances. Practical adhesion can be evaluated with either ultimate parameters (Fmax or Dmax) or the critical strain energy release rate, using the three point flexure test (ISO 14679-1997). We observe that, for the same system, the ultimate load decreases while residual stresses increase when the liquid/solid time increases. Ultimate loads and residual stresses depend on the metallic surface treatment. For these systems, the critical strain energy release rate which takes into account the residual stress profile and the Young's modulus gradient remains quite constant whatever the metallic surface treatment was. These variations will be discussed and correlate to the formation mechanisms of the interphase.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.2
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• pp.63-70
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• 2016

The distributed systems managed by K-water were surveyed to study the characteristic of disinfection-by-product (Trihalomethans & Haloacetic acids) formation and the correlations between the concentrations of disinfection-by-product and physico-chemical parameters. Five distribted system were selected according to their water ages and the degree of deterioration of their pipelines. Total seven items including Trihalomethans (THMs), Haloacetic acids (HAAs), BDOC, DOC, pH, chlorine residual, and temperature were analysed in monthly basis. The concentration of organic matter were increased according to water age and pipeline deterioration in this study. The coefficient of determination between the decline of residual chlorine and the increase of water age was revealed as high. Also, the coefficient of determination between the decline rate of residual chlorine and the increase of the Trihalomethans concentration were studied as high. Furthermore the longer water age is the bigger the effect on Trihalomethans formation and temperature. However, the coefficient of determination between the concentraion of Haloacetic acid and water age, residual chlorine, and temperature were revealed as low in this study.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.299-307
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• 2007

Changes in nitrite content, TBARS content and color of meat products during storage were examined as part of studies addressing the reduction of residual nitrite and to ensure the safety of meat products. All 4 kinds of domestic meat product tested, Vienna sausage, bacon, smoked-ham and Dduggalbi, manufactured by C and L domestic companies had very low contents of residual nitrite, for below the legal tolerance limit of 70 ppm, and the residual nitrite decreased with storage. The reduction in nitrite content differed with each product, showing the greatest reduction in Vienna sausage and the least reduction in bacon when stored at $4^{\circ}C$. On the other hand, when stored at $-20^{\circ}C$, the nitrite content of bacon decreased more rapidly than the other meat products. The results of this study show that the nitrite content of meat products decreases during storage, and that the rate of decrease is quite dependent on the storage temperature. In addition, the nitrite contents of most domestic meat products are very low compared to the legal limits, thus the health risks of nitrite in meat products might not be of great concern. More research on the reduction of residual nitrite and on the development of alternatives to nitrite is necessary.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.10
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• pp.1145-1153
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• 2011

The purpose of this study is to relieve the residual stress of Al6061 using cryogenic heat treatment. Experimental T6 and cryogenic heat treatments were carried out to define the convective heat-transfer coefficient, which was then applied in the finite-element method (FEM) to predict the residual stress. The predicted residual stress was compared with the residual stress measured by X-ray diffraction (XRD), and the results were in good agreement. The mechanical properties were estimated by measuring the electrical conductivity and hardness. In addition, the size and formation of the precipitations were observed by TEM and XRD analysis for both T6 and cryogenic heat treatments. The effects of the cryogenic heat treatment on the residual stress, mechanical properties, and precipitation of Al6061 alloys were thus confirmed.