• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.9-15
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• 2016

The part of a building with the biggest energy loss is the exterior and many studies are actively conducted to reduce the energy loss on that part. However, most studies consider the window frames and insulation materials, but many studies do not discuss the concrete that takes more than 70% of the exterior. In order to minimize the energy loss of buildings, it is necessary to enhance the concrete's insulation performance and studies need to be conducted on this. Therefore, this study used a micro foam cell admixture, calcined diatomite powder, and lightweight aggregates as a part of a study to develop a type of concrete with improved insulation performance that has twice higher thermal conductivity compared to concrete. It particularly secured the porosity inside concrete to lower thermal conductivity. As a result of the experiment, the slump and air capacity showed fair results, but all mixtures containing micro foaming agent showed 14.3~35.1% lower mass per unit of volume compared to regular concrete. Compressive strength decreased slightly due to the materials used to improve the insulating performance, but it all satisfied this study's target strength(24MPa). Thermal conductivity was up to twice higher than that of regular concrete.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.8
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• pp.877-885
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• 2013

A seawater pipe of the engine room in the ships is being surrounded with severely corrosive environments caused by fast flowing of the seawater, containing aggressive chloride ion and high conductivity etc.. Therefore, the leakage of the seawater from its pipe have been often occurred due to its local corrosion by aggressive chloride ions. Subsequently, its leakage area is usually welded by AC shielded metal arc welding with various electrodes. In this study, when the sea water pipe is welded with several types of electrodes such as E4301, E4311, E4313 and E4316, a difference of the corrosion resistance on the welding metal zones was investigated using an electrochemical method, observing microstructure, measuring polarization behaviors and hardness. The weld metal zone welded with E4313 electrode exhibited the lowest value of hardness compared to other weld metal zones. In addition, its zone indicated also the best corrosion resistance than those of other weld metal zones. Furthermore, all of the weld metal zones revealed a relatively better corrosion resistance than those of the base metal zones. and also showed higher hardness than the base metal zones.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1117-1123
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• 2003

The effects of heat treatment on the physical and physical and physiological properties of wax gourd (Benincasa hispida) were examined. The applied heat treatments were autoclaved at $121^{\circ}C$ for 1 hr, boiled for 30 min, and microwaved at 680 W for 5 min. The water retention capacity (WRC) of the wax gourds was 9.43 g/g for the microwaved samples, 5.12 g/g for the boiled samples, 4.63 g/g for the raw samples, and 2.61 g/g for the autoclaved samples. Heat treatment caused to increase swelling by up to $4.4{\sim}7.8\;mL/g$. Calcium binding capacity of heat-treated wax gourd increased in the order of microwaved, boiled, raw, autoclaved samples. Scanning electron microscopy (SME) showed that autoclaving caused the most severe structural modifications, while microwave treatment produced the least modifications. The retarding effect on glucose and bile acid transport depended on the heat treatment. Only boiling showed the glucose retardation effect. Bile acid retardation effect increased in order of boiling (22.9%), autoclaving (17.1%), microwave treatment (14.3%), and raw wax gourd (8.6%). The cadmium retardation effect was significantly high in all samples.

• Korean Journal of Materials Research
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• v.23 no.12
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• pp.672-679
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• 2013

$Fe_4[Fe(CN)_6]_3$ coated on a mica or $TiO_2$/mica surface as infrared reflective blue pigment was prepared by a hydrothermal method. $Fe_4[Fe(CN)_6]_3$, used as coloring agent, was uniformly coated on mica or $TiO_2$/mica under the optimized condition of a 1.2 : 1 weight ratio between iron(III) chloride hexahydrate and potassium ferrocyanidetrihydrate at the initial pH level of 4.5 at $70^{\circ}C$. The infrared (IR)-reflective pigments were characterized by SEM, Zeta-potenial, FT-IR, and UV-VIS NIR spectrophotometry. Especially the CIE color coordinate and total solar reflectance(TSR) properties of the pigments were investigated in relation to variation of the coating and coated substrate thicknesses. Isolation-heat paint was prepared with 20 wt% blue pigments fully dispersed in acryl-urethane resin and several additives to coat the film uniformly. The films were also measured with CIE color coordinate, TSR, and the surface temperature was recorded by an isolation-heat measuring system. The pigments and films of $Fe_4[Fe(CN)_6]_3$ coated on mica and $TiO_2$/mica showed high TSR values compared with the TSR value of $Fe_4[Fe(CN)_6]_3$ itself. According to the increase of TSR value, the property of isolation-heat is effective. To realize the optimal blue color, we applied the the pigment to $TiO_2$ coated mica(TM(b)) which has blueish interference color. The pigment of $Fe_4[Fe(CN)_6]_3$ coated on TM(b) shows a strong blue color compared with that of $Fe_4[Fe(CN)_6]_3$ coated on $TiO_2$/Mmca(TM(w)), which has a whitish interference color.

• Journal of Ginseng Research
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• v.44 no.4
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• pp.570-579
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• 2020

Background: Many researchers reported that the various immune activities of red ginseng are due to acid polysaccharides. But, the exact structural characteristics of the acidic polysaccharide in red ginseng have not been fully elucidated. Therefore, we isolated the acidic polysaccharide from red ginseng and characterized the structural property of the active moiety of this polysaccharide, which contributes to the immunostimulatory activity of red ginseng. Methods: A polysaccharide (RGP-AP-I) was purified from red ginseng via size-exclusion chromatography using Sephadex G-100. Immunostimulatary activity of RGP-AP-I was investigated via anti-complementory and macrophage stimulatory activity. The structure of RGP-AP-I was characterized by HPLC, sugar composition, β-glucosyl Yariv reagent and methylation analysis. Results: Peritoneal macrophages stimulated using RGP-AP-I significantly augmented the production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factor (TNF)-α. The primary structure of RGP-AP-I was elucidated by assessing its sugar composition and methylation analysis. RGP-AP-I is a 96 kDa acidic polysaccharide, and comprises nine different monosaccharides, which mainly include sugars such as rhamnose (Rha, 9.5%), galacturonic acid (GalA, 18.4%), galactose (Gal, 30.4%), and arabinose (Ara, 35.0%). RGP-AP-I exhibited an considerable reaction with the β-glucosyl Yariv reagent, revealing the presence of arabino-β-3,6-galactan. Methylation analysis indicated that RGP-AP-I comprises 21 different glycosyl linkages, such as 3-, 4-, 6- and 3,6-linked Galp; 5-linked Araf; 2,4-linked Rhap; and 4-linked GalAp, which are characteristics of rhamnogalacturonan I (RG-I). Conclusion: we assumed that the immunostimulatory activity of RGP-AP-I may be due to the RG-I structure, which comprises a main chain with a repeating linkage unit, [→2)-Rhap-(1→4)-GalAp-(1→] and three groups of side chains such as (1→5)-linked arabinan, (1→4)-linked galactan, and arabino-β-3,6-galactan, which branch at the C(O)4 positions of Rha residues in the main chain of RGP-AP-I.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1146-1152
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• 2005

Graft copolymers were synthesized from methylcellulose(MC) and acrylic acid(AA) with active carboxyl groups in the presence of potassium persulfate($K_2S_2O_8$) initiator to enhance adsorption capacity of toxic heavy metal such as $Pb^{2+}$ and $Cu^{2+}$ from wastewater. The resulting grafted copolymers(MC-g-AA/PAA) were mixture of the graft copolymers from MC and AA(MC-g-AA) and polyacrylic acid homopolymers(PAA). The degree of palling was increased with rising concentration of monomer and initiator under the reaction conditions at $60^{\circ}C$, 3 hrs. The water insoluble property of MC-g-AA showed more than 19.7% degree of grafting. So that it could be an adsorbent of heavy metals. Adsorption characteristics of the MC-g-AA were evaluated depending on the degree of grading, pH of wastewater, adsorption time, dosage of MC-g-AA and concentration of heavy metals in the different conditions. Degree of grafting, and initial concentration of heavy metal ions increased, the adsorption amount of $Pb^{2+}$ and $Cu^{2+}$ increased, but added MC-g-AA increased, the adsorption amount per unit weight of $Pb^{2+}$ and $Cu^{2+}$ decreased. The MC-g-AA showed the high $Pb^{2+}$ and $Cu^{2+}$ adsorption amount in the range pH $4{\sim}6$. Also all of $Pb^{2+}$ and $Cu^{2+}$ ions reached in adsorption equilibrium in neighborhood 4 hours. The adsorption of heavy metals described by Freundlich isotherm, it was determined the value of l/n of $Pb^{2+}$ and $Cu^{2+}$ that 0.4294 and 0.3453, respectively.

• The Korean Journal of Physiology
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• v.2 no.1
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• pp.39-45
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• 1968

Recently, in this department, pressure-displacement curve and breaking tension of dog and human tympanic membrane were studied using intact, fresh or dried tympanic membrane attached to external auditory meatus. However, physical property, proper elasticity-Young Modulus, of the tympanic membrane has not been clarified yet. Present study is attempted to further clarify proper Young Modulus of tympanic membrane, and to distinguish possible difference between layer of stratum radiatum and layer of stratum circulare of tympanic membrane in breaking tension and in Young Modulus. Tympanic membrane was excised from sacrificed dog, and preparation was made into the size of approximately 1 mm in width and 3 mm in length. In fresh or dried tympanic membrane, which was dried at $80^{\circ}C$ for 24 hrs., some preparations were made along the long axis parallel to the fibers of radial direction, and others were made along the long axis perpendicular to the radial fibers-circular direction. Breaking tension and displacement according to loading, were measured and Young Modulus was calculated in tympanic membrane preparations under the different experimental conditions. Results obtained are summarized as follows : 1. Young Modulus of fresh tympanic membrane in radial direction was $6.57{\times}10^8\;dyne/cm^2$, and that of fresh preparation in circular direction was $1.68{\times}10^8\;dyne/cm^2$. The Young Modulus of fresh tympanic membrane in radial direction resembles to that of silk and whale moustache. In dried tympanic membrane, Young Modulus of preparation of radial direction was $30.2{\times}10^8\;dyne/cm^2$ and that of preparation in circular direction was $25.0{\times}10^8\;dyne/cm^2$. 2. Breaking tension of fresh tympanic membrane was 44.9 gm/mm in radial preparation, and 7.9 gm/mm in circular preparation. In dried tympanic membrane, breaking tension was 46.7 gm/mm in preparation of radial direction, and 17.2 gm/mm in preparation of circular direction. 3. Much smaller breaking tension of the circular preparation-one fifth to the radial preparation-seemed to be responsible for the higher incidence of circular fiber breaking in tympanic membrane performation caused by trauma or sudden change in atmospheric pressure. 4. The correlation seemed to be very close between breaking tension and Young Modulus in tympanic membrane.

• Journal of Ginseng Research
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• v.33 no.3
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• pp.234-239
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• 2009

This study aims to establish the directions for the optimal nutrient contents determined by soil and leaf analyses. The study is to be used as a source for basic information in investigating the effects of nutritional environment on ginseng growth at the fields of Ansung region in Gyeonggi province. The physical property of soil porosity is closely related to ginseng growth, with more than 50% of good growth in the field. The optimal range of chemical properties in soil was analyzed as 0.20-0.28% T-N, 500-900 mg/kg Av.P$_2$O$_5$, and 2.3-3.5 cmol$^+$/kg Exch.Ca. The optimal range of inorganic nutrient contents in leaves was also analyzed. P value was less than 0.25%, and Mg was more than 0.22%. Other elements were not found clearly. The ratios of N/P, N/Mg, K/Mg, and Ca/P of leaves with good growth in the field showed 10<, 10-13, <14, 1<, respectively. In addition, the Ca:Mg:K ratio of the Exch.cation (cmol$^+$/kg) may be useful as an indicator in the assessment of plant growth in ginseng.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.997-1004
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• 2006

This study was performed to investigate the storage properties of emulsion-type sausage added with Glycyrrhiza uralensis and Curcula longa hot water extracts (GCHE) extracted at $10^{\circ}C$ for 35 days. The TBARS values of sausages containing 1.0 and 5.0% GCHE were lower than that of control. The bacterial count and VBN contents of all the samples were significantly increased during the storage periods, except the group with 5.0% GCHE. The redness of all the samples was lower than that of control, while yellowness of all the samples was higher than that of control. The nitrite scavenging abilities of the sausages containing 1.0 and 5.0% GCHE were higher than that of the control. It is suggested that the addition of 1.0% hot water extracts extracted from these plants may be a potential substitute for the use of nitrite to extend shelf-life of sausages.

• Journal of Korean Port Research
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• v.10 no.2
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• pp.17-29
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• 1996

It is required to consider pricing and non-pricing factors and external economy in order to achieve the objects of physical distribution system in a port. Recently, among the three factors, much attention has been paid to non-pricing factor in the system. Although physical distribution service in a port(PDSP)has been frequently mentioned in documents and literature related to port and shipping studies, few study on it has not been systematically and scientifically made due to the following problems; $\circ$ there are not proper criteria to evaluate level and quality of PDSP and as a result it is difficult to set up a unified standard for doing so. $\circ$ algorithms to evaluate problems with complex and ambiguous attributes and multiple levels in PDSP are not available. This thesis aims to establish a paradigm to evaluate PDSP and to abvance existing decision making methods to deal with complex and ambiguous problems in PDSP. To tackle the first purpose, extensive and thorough literature survey was carried out on general physical distribution service, which is a corner stone to handle PDSp. In addition, through interviews and questionnaire to the expert, it have extracted 82 factors of physical distribution service in a port. They have been classified into 6 groups by KJ method and each group defined by the expert's advice as follows; a. Potentiality b. Exactness c. safety d. Speediness e. Convenience f. Linkage Prior to the service evaluation, many kinds of its attributes must be identified on the basis of rational decision owing to complexity and ambiguity inherent in PDSP. An analytical hierarchy process (AHP) is a method to evaluate them but it is not applicable to PDSP that have property of non-additivity and overlapped attributes. Therefore, probablility measure can not be used to evaluate PDSP but fuzzy measure is required. Hierarchical fuzzy integral method, which is merged AHP with fuzzy measure, is also not effective method to evaluate attributes because it has vary complicated way to calculate fuzzy measure identification coefficient of attributes. A new evaluation algorithm has been introduced to solve problems with multi-attribute and multi-level hierarchy, which is called hierarchy fuzzy process(HFP).Analysis on ambiguous aspects of PDSP under study which is not easy to be defined is prerequisite to evaluate it. HFP is different from algorithm existed in that it clarified the relationship between fuzzy measure and probability measure adopted in AHP and that it directly calculates the family of fuzzy measure from overlapping coefficient and probability measure to treat and evaluate ambiguous and complex aspects of PDSP. A new evaluation algorithm HFP was applied to evaluate level of physical distribution service in the biggest twenty container port in the world. The ranks of the ports are as follows; 1. Rotterdam Port, 2. Hamburg Port, 3. Singapore Port, 4. Seattle Port, 5. Yokohama Port, 6. Long beach Port, 7. Oakland Port, 8. Tokyo Port, 9. Hongkong Port, 10. Kobe Port, 11. Los Angeles Port, 12. New york Port, 13. Antwerp Port, 14. Felixstowe Port, 15. Bremerhaven Port, 16. Le'Havre Port, 17. Kaoshung Port, 18. Killung Port, 19. Bangkok Port, 20. Pusan Port