• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.74-84
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• 2002

This experiment was carried out to evaluate supplemental effects of various preservatives to preserve the Brewers grain and Soymilk from decay and degeneration. The NaCl, organic acid(Ca-propionate), microbial fermenter(H/MF inoculant), and methionine hydroxy analogue(MHA) were used as additives in order to compare preservability of brewers grain and soymilk by-product during 20 days at July to August. Most treatments were appeared rapid decay and degeneration as soften and covered with molds on surface from the early days of experiment. However, MHA treatments showed any change until 20 days of storage. In terms of pH and $NH_3-N$ contents, only MHA treatment showed a stable and low value. The other treatments including Control showed high values as time flowed or unstable states. In conclusion, when high moisture agricultural by-product was treated by over 5% of MHA, there was no significant physicochemical changes in long term preservation over 20 days at summer season.

• Polymer(Korea)
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• v.26 no.2
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• pp.237-244
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• 2002

Mechanical properties, flow characteristics and chemical resistance of polycarbonate (PC)/polybutylene terephthalate (PBT) /impact modifier (IM) blends were investigated over the various composition ranges of PC and PBT. Mechanical properties of the PC/PBT/IM blends for different IMs, butadiene based IM and butyl acrylate based IM, were studied for various compositions of the IMs. Impact strength at low temperature was also observed. For the study of chemical resistance of the PC/PBT/IM blends, the blonds were dipped in organic solvent, thinner, and then variations of mechanical properties were analyzed. Tensile and flexural strengths were increased linearly and heat distortion temperature (HDT) also increased as PC content in the blends increased. Impact strength increased drastically as PC content increased up to 50 wt% and stayed stable value. Flowability decreased as PC content increased. Impact strengths of the blend were various for different IMs. Butyl acrylate based IM showed slightly higher impact strength than butadiene based IM for the temperature above $0^{\circ}C$. However, butadiene based IM showed remarkably higher impact strength than butyl acrylate based IM for the temperature below $0^{\circ}C$. Through the experiment of chemical resistance it was observed that tensile and flexural strengths decreased, and impact strength increased as PC content in the blends increased. PC in the blend would become mild and ductile when it contacted with organic solvent. Thus the impact strength increased while tensile and flexural strength decreased.

• Economic and Environmental Geology
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• v.41 no.3
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• pp.287-297
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• 2008

In order to estimate the preliminary development feasibility according to the commodity, the content of 8 strategic metallic commoditites(Pb, Zn, Cu, Fe, Mo, W, Au, U) in 68 ore specimens obtained from 34 metallic mines within the Taebaegsan-Hwanggangri mineralized zone were analyzed. Analytical results are as follows. The ore specimen of Sangdong mine contained 23% copper(cut-off grade=0.7%) and those of Cheongil and Samhwanghak mines contained average 5% zinc(cut-off grade=2.0%). Especially, the detailed investigation on the above-mentioned mines is required. And, in case of molybdenum(cut-off grade=0.02%) content in Yeonhwa No. 2(0.04%) and Hong-cheon mine(0.02%), and lead(cut-off grade=0.58%) content in Wongasa mine(0.70%), and gold(cut-off grade=10ppm) content in Dongmyoung(279ppm) and Samhwanghak mine(251ppm), it is required to elastically carry out the revaluation on reopening of mines in terms of the international metal price. On the other hand, in case of uranium, iron and tungsten, it is thought that there are no mines with the development potential value in this study.

• International Journal of Highway Engineering
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• v.4 no.1 s.11
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• pp.149-159
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• 2002

This study was performed to estimate the high-speed direct tensile strength(DTS1), low-speed direct tensile strength(DTS2) , indirect tensile strength(ITS) resilient modulus(MR) and stiffness index(SI) of sand asphalt mixture based on the absolute viscosity, kinematic viscosity, penetration, softening point and PG grade of binder. DTS2 showed higher correlation with the physical properties than other properties of mixture, and the next was DTS1, ITS, SI and MR in order. Among binder properties, PG grade showed the highest relation with DTS2. Therefore. it was found that the high DTS mixture could be made when the binder with a high PG grade was used. However, since the individual physical property showed a relatively low correlation, various properties were used together in regression analysis. The estimation models of DTS and ITS were over 0.99, respectively. R2 of MR and SI estimation models were over 0.91 and 0.93, respectively. It was concluded that mechanical properties could be estimated with a high coefficient of determination from those physical properties.

• Korean journal of food and cookery science
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• v.15 no.6
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• pp.633-638
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• 1999

This study was conducted to investigate the effect of quality preservatives on minimally processed white radish for Kkakttugi, hot radish Kimchi, preparation during storage at $4^{\circ}C$ and $20^{\circ}C$. The firmness of minimally processed white radish decreased during storage at $4^{\circ}C$ and $20^{\circ}C$. However 1% $CaCl_2$ and 2% NaCl+2% sucrose treatments were effective to maintain the firmness of cut radishs. For color, Hunter L values decreased more in the samples stored at $20^{\circ}C$ than at $4^{\circ}C$, while a values showed a slight increase at both storage temperatures. The b values (browning index) showed a notable increase during storage at $4^{\circ}C$ and $20^{\circ}C$. Vitamin C content decreased during storage at both temperatures by 10.4% ~ 95.9%. At both storage temperatures, vitamin C content was highest in the samples treated with 1% NaCl+1% sucrose. For organic acid, while the content of malic acid decreased those of lactic and acetic acid increased during storage.

• Journal of Adhesion and Interface
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• v.16 no.1
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• pp.29-34
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• 2015

Hydrocarbon resins, which are defined as low molecular weight, amorphous, and thermoplastic polymers, are widely used as tackifier for various types of adhesives, as processing aids in rubber compounds, and as modifiers for plastics polymers such as isotactic polypropylene. Typically, hydrocarbon resins are non-polar, and thus highly compatible with non-polar rubbers and polymer. However, they are poorly compatible with polar system, such as acrylic copolymer, polyurethanes, and polyamides. Moreover, recently the raw materials of hydrocarbon resin from naphtha cracking had been decreased because of light feed cracking such as gas cracking. To overcome this problem, in this study, novel hydrocarbon resins were designed to have a highly polar chemical structure which material is sustainable. And, it was successfully synthesized by Diels-Alder reaction of dicyclopentadiene monomer and sorbic acid from blueberry as renewable resources. Acrylic resins were formulated with various tackifiers solution including sorbic acid grafted hydrogenated dicyclopentadiene hydrocarbon resins in acrylic adhesive and rolling ball tack, loop tack, $180^{\circ}$ peel adhesion strength, and shear adhesion strength were measured. The properties depend on the softening point and polar content of tackifiers.

• Archives of design research
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• v.17 no.4
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• pp.15-26
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• 2004

After 19th century of Chosun Dynasty Gilsnagmunja-do such as longevity, good fortune, health, well-being which was explosively prevalent and Hyojemunja-do which was panoramically decorated with eight characters of filial piety, fraternal devotion, loyalty, trust, courtesy, commitment, integrity and humility for enlightment of the public under the name of political ideology are consistency or same origin in traditional concept of Orient. Therefore, in view of Western standard, they are showing an illustration and a photograph of characters in design. There are some differences in way of expressions. They were considerably popular not only in Chosun Dynasty but in China, Japan and Vietnam where belong to the cultural territory of chinese characters. Though, Hyojemunja-do which was built-up in the late period of Chosun Dynasty and developed fro chinese mode is a very peculiar iconography and mode of Chosun Dynasty. Hyojemunja-do is also classified from Chinese Nianhua designed for supply of Conficianism ethics or Folk Painting designed for practical use in chinese cultural territory. In the late period of 19th century, Hyojemunja-do which was re-built with creative modeling has been developed in peculiar mode in the province of Kyunggi, Kangwon(Kwan dong region), Kwanseo region, Jeju island and Namdo region by the diversified level of painters.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.1
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• pp.131-141
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• 2011

This study, as a purpose of base study for landscape redevelopement of Seowon, pointed out problems of planting patterns in each sector and suggested an alternative through analyzing old literature, complete enumeration survey in each sector and taking aerial images. the conclusions drawn from this study are as follows. A Pilam Seowon(historic site no 242) is located in a Pyungya-Sanrok(plain and mountain) district in Jangsung-gun and has Junhak-Humyo(Study room in the front and Shirne in the back) type. 23 taxonomic group of arbor, 6 taxonomic group of shrub and 5 taxonomic group of flowers are planted high-densitily in limited flat surface. It can be classified into being planted by family and being planted through landscape redevelopement in 1980s. Korean traditional trees are planted in this area like Pinus densiflora, Juniperus chinensis L., Thuja orientalis L., Zelkova serrato Makino, Sophora japonica L., Lagerstroemia indica, Prunus mume include Ginkgo biloba which is old big tree and is registered in Jangsung-gun as protected trees. The tea tree in this area was introduced from wild tea plantation in Yonhwa moutain and was planted. From now on, we have to pay consideration a form management of planted trees in the historical area, rearrangement of plant density due to over planting, removal of alien trees like Pinus bungeana and Canna generalisa, prevention a dwarfishness of main area due to over planting in outside facilities, recovery a alienation among each planting area, and planting concept from plants drawings on wall of buildings can be suggested. The implications of this case study is that introduction of over planting can make more problems like losing sense of place. Therefore, we must do a actual state survey on traditional landscape area like Seowon from preservation point of view.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.107-116
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• 1998

Based on the differential growth response to exogenous gibberellic acid ($GA_{3}$) between semi-dwarf wheat(Triticum aestivum) and wild oat(Avena fatua), we examined the possibility of improving the selective performance of several herbicides by $GA_{3}$ application and the physiological background of $GA_{3}$-induced increase in herbicidal activity. Growth of wild oat was 4 to 5 times higher than that of wheat by $GA_{3}$ treatment. Pretreatment of wild oat seed with 300 ppm $GA_{3}$ increased the herbicidal activities of trifluralin and isoproturon by soil-surface application, but not of alachor and metsulfuron-methyl. $GA_{3}$ applied simultaneously with post-emergence herbicides resulted in a significant or moderate improvement of the efficacy of such herbicides as tralkoxydim, fenoxaprop-ethyl, metsulfuron-methyl, metribuzine and isoproturon, but not in the mixtures of oxyfluorfen or paraquat with $GA_{3}$. In the sequencial treatment of tralkoxydim and $GA_{3}$ at interval of one-day, $GA_{3}$ applied prior to tralkoxydim significantly increased a chlorosis and desiccation of leaf without affecting the growth inhibition by tralkoxydim. Tralkoxydim followed by $GA_{3}$ application had lower herbicidal activity than that of $GA_{3}$ followed by tralkoxydim treatment. Electrolyte leakage response of $GA_{3}$-pretreated or $GA_{3}$-untreated wild oat leaf against several compounds inducing membrane. peroxidation was compared. Differencial responses were observed in oxyfluorfen and isoproturon treatments with an increased electrolyte leakage in $GA_{3}$-pretreated tissue, but not in paraquat and rose bengal treatments. These results suggest that $GA_{3}$-induced increase in herbicidal activity is likely to be dependent on a herbicide type and may be due to activation of a metabolic ability related with herbicidal reponse as well as an increase in the herbicide absorbtion and translocation, rather than due to membrane and cell wall extention induced by $GA_{3}$, which in turn makes the herbicides easily enter.

• Neonatal Medicine
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• v.15 no.2
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• pp.142-151
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• 2008

Purpose : The aim of this study was to compare the clinical effects of modified porcine (Curosurf$^{(R)}$) and bovine (Newfactan$^{(R)}$) surfactants in the treatment of neonatal respiratory distress syndrome. Methods : Between April 2004 and December 2006, 65 neonates (birth weight ${\leq}$2,500 g and gestational age ${\leq}$35 weeks) with neonatal respiratory distress syndrome were treated in our neonatal intensive care unit with surfactant. Thirty-one neonates received Curosurf$^{(R)}$ and 34 neonates received Newfactan$^{(R)}$. The neonates were not enrolled if they had major congenital anomalies or meconium aspiration syndrome. We compared the changes in respiratory parameters after surfactant instillation, the incidences of acute and chronic complications, and the mortality between the two treatment groups. Results : Neonatal and maternal demographic characteristics were not different between the groups. The patterns of change in the respiratory parameters after surfactant instillation were not statistically different between the groups. The incidences of surfactant reinstillation and acute complications, such as pneumothorax, patent ductus arteriosus, pulmonary hemorrhage, and grade 3-4 intraventricular hemorrhage, were not different between the neonates who received Curosurf$^{(R)}$ and the neonates who received Newfactan$^{(R)}$. There were no statistically significant differences in the duration of mechanical ventilation, oxygen therapy, hospitalization, prevalence of bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, necrotizing enterocolitis, and mortality between the groups. Conclusion : In the present comparative study, no significant differences in the clinical effects of Curosurf$^{(R)}$ and Newfactan$^{(R)}$ were observed.