• Composites Research
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• v.13 no.3
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• pp.48-57
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• 2000

Fracture analysis of coating cracking on a substrate system described in a companion paper was applied and verified by four-point bending tests. The multiple cracking of coating was predicted using a fracture mechanics approach. The strain energy release rate (G) due to the formation of a new crack in a coating was obtained. A crack density vs. strain data of metallic and polymeric substrate was used to get the in-situ fracture toughness of coating with respect to various baking time and temperature. The $G_c$ was decreased as the baking temperature and time was increased. This paper gave insight about usefulness of four-point bending test for fracture toughness evaluation of coating and it gave a new method for in-situ coating toughness.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.59-65
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• 1973

The details of design procedure, practically used for the construction of fluidized bed dryer system of the Super Cereal Plant of 250, y capacity were presented. The plant was in its entirety designed and constructed solely by domestic engineering potenality with local construction materials. In the drying process, the water content of cooked kernel of wheat is reduced from about 23% to about 14% and the conversion of starch contained in the endosperm to ${\alpha}$-starch is to be completed by contacting with hot combustion gas of kerosene at about 90-130$^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.530-532
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• 1990

The moisture sorption behaviors of dry corn(DC). dry-corn (DCC) and soaked-rooked corn(SCC) at $25^{\circ}C$ were analyzed. The corn was soaked in water at $26^{\circ}C$ for 8hr. The cooking times for DCC and SCC were 30 and 20min. respectively, at $80^{\circ}C$. Desorption occurred for DC and DCC at RH below 23% and SCC at RH below 33% during storage. Moldiness was observed in all samples at RH 97%, after 192hr for DC and 288 hr for both DCC and SCC. At the same water activity. SCC sample had the highest moisture content, followed by DC. The SCC sample had the highest monolaver value and sorption heat. Stability isotherms indicated that DC and SCC had better storability than DCC.

• Journal of the Korean earth science society
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• v.21 no.4
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• pp.423-436
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• 2000

The lithofacies, biofacies, and paleosol development of the Jindong Formation, the Geoncheonri Formation, and the lacustrine deposits of Mt. Hwangryeong at Pusan, which occur in the southeastern part of the Gyeongsang Basin, were analyzed in comparative sedimentology and in stratigraphy. The common features of these lacustrine deposits are: 1) clastic deposits are prevailing, 2) deltaic deposits are not associated, 3) mudflat deposits are common, and 4) stromatolites are absent. The distinct differences among these deposits are: 1) in the Jindong Formation, the mudflat deposits are predominant, pedogenic calcretes are commonly present, and dinosaur tracks frequently occur, compared with other two lacustrine deposits, and 2) in the Geoncheonri Formation, invertebrate fossils are relatively common and storm deposits are not recognized, compared with other deposits, and 3) evaporite mineral casts and tuffaceous turbidite deposits are common in the Mt. Hwangryeong lacustrine deposits. In stratigraphy, the Geoncheonri Formation is correlated with the lower part of the Jindong Formation, and the Mt. Hwangryeong lacutsrine deposits are deemed to overlie the Jindong Formation. On the basis of comparative sedimentology and stratigraphic relationship among these lacustrine deposits, general paleoenvironements of the southeastern part of the Gyeongsang Basin from the late Hayang time to the early Yucheon time are interpreted as follows. During the late Hayang time, tectonic and volcanic activities were generally inacitive in the Gyeongsang Basin, and lacustrine environments expanded since the paleoclimatic condition became less arid compared with the middle Hayang time. In general, however, paleoclimate during the late Hayang time was still arid, and wetting and drying periods were alternated. The occasional occurrences of severe droughts were also characteristic of the late Hayang time. Mudflats existed in wide area in the southeastern part of the Gyeongsang Basin during the late Hayang time, and sedimentation rate was accordingly low. The sedimentation rate became relatively high during the latest Hayang time and the early Yucheon time since tectonic and volcanic activities had been active. Generally arid climate continued for the early Yucheon time, enough for evaporite minerals to precipate occasionally.

• Resources Recycling
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• v.15 no.1 s.69
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• pp.58-65
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• 2006

A new technology for refused derive fuel(RDF) utilization in circulating fluidized bed is under development. The RDF is tested in a bench scale circulating fluidized bed(CFB) combustor and its burning characteristics were investigated and collected as design parameters. The combustions were controllable and the HCl emission which is most important toxic emission were below 150 ppm at the exit of the combustor. The differences between conventional coal homing circulating fluidized bed boiler and the exclusive RDF boiler were studied and commercial scale co-generation CFB for RDF was designed.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.124-134
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• 2005

A new technology for refused derive fuel(RDF) utilization in circulating fluidized bed is under development. The RDF is tested in a bench scale circulating fluidized bed(CFB) combustor and it's burning characteristics were investigated and collected as design parameters. The combustions were controllable and the HCl emission which is most important toxic emission were below 150ppm out of combustor. The differences between conventional coal burning circulating fluidized bed boiler and the exclusive RDF boiler were studied and commercial scale co-generation RDF CFB's were designed.

• Korean Chemical Engineering Research
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• v.58 no.2
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• pp.307-312
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• 2020

Fluidized bed reactors operated in subatmospheric pressure has been focused because several industrial applications such as vacuum drying and plasma cvd requires reduced pressure fludization. However, the hydrodynamics of fluidized beds in subatmospheric pressure has not been extensively investigated. The pressure drop in the fluidized bed has been measured with variation of downstream pressures from 1.33 to 101.3 kPa in the shallow and deep fluidized beds under the sub-atmospheric pressures. The obtained minimum fluidization velocity of powders is a function of pressure due to the changes of gas density and mean free path. We can experimentally determine the critical Knudsen number and the critical pressure to define the slip regime significantly to influence the hydrodynamics of fluidized beds.

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.510-518
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• 2012

The Holocene climate change has been studied based on humus analysis of sediments that came from the Nam River basin in the Jinju, Gyeongnam. Humus and soil organic carbon analyses were performed to interpret the climate change and OSL dating and radiocarbon dating were conducted to determine the age of the sediments. The age determinations revealed that the sediments were formed approximately from $10,000{\pm}100$ yr. BP to $4,370{\pm}50$ yr. BP (2,970 BC) The deposits were classified into five layers based on sediments color and texture, and the climate change of each layer has been interpreted. The general climate was found out to be warm. The study result illustrated that section I was the lowest layer and section V the highest among the five surveyed sections. One the other hand, relatively cold events were detected in the sections ranging from I and II to III in terms of temperature. In term of humidity, sections II and III are estimated to have been relatively dry. Sections IV and V were relatively warm and dry, and the section IV tends to be warmest of the entire sedimentary. In addition, there is a tendency that the total soil organic carbon shows relatively high values under the cooler and humid climatic condition.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.414-422
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• 1992

To keep up with urgent need of continuous, effective and rapid drying unit, a fluidized bed drying system with computer controlling air temperature, velocity and relative humidity was designed. This study was attempted to determine physical properties and some basic experiments of fluidized bed d교ing of barley. Also experimental data of the designed fluidized bed drying system using the barely were compared with those of published equations to confirm the reliability of the system and the following results were obtained. The physical dimension husked barley were shown larger than that of naked barley from the experiment. When air temperature. relative humidity and charged amount were $35^{\circ}C$, 30% and 300g respectively, the minimum fluidization velocity of naked and husked barley were found 1.5 m/s and 1.7 m/s. And the optimum fluidization velocity was shown as 3.0 m/s from the experiment. The empirical equation of $U_{mf}$ in this fluidized system was obtained as follow; $U_{mf}^2= \frac{{\phi_s}\;d_p}{Hk}\;{\cdot}\;\frac{(\rho_s-\rho_g)g\;{{\varepsilon}_{mf}^3}} {\rho_g}(Re_p>1,000)$ Where HK=0.4881 for naked barley, 0.6649 for husked barley.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.436-441
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• 2011

This study was performed to evaluate physico-chemical properties and antioxidant activity of pork patties with tomato powder as affected by water solubility. Fresh tomatoes were homogenized and dried in a $60^{\circ}C$ oven. Dried tomato powder was added to double deionized-water and stirred. The soluble and insoluble portions were collected by freeze-drying. Thus, total dried powder (T1) and water soluble (T2) and insoluble powders (T3) were prepared for the experiment. Pork patties containing 0.5% water insoluble powder had the highest redness and yellowness values among the treatments (p<0.05). Thiobarbituric acid reactive substance values of pork patties containing 0.5% dried tomato powder were lower than those of the control (p<0.05) and not different from those of the reference (0.01% BHT). Total bacteria and Enterobacteriaceae (VRB) tended to increase with increasing storage time from 0 to 14 d; however, these values were not statistically different among treatments. These results suggest that lipid oxidation may be suppressed by adding tomato powder to pork patties; thus, tomato powder could be used as a natural antioxidant in meat products as a partial replacement for synthetic antioxidants.