• Food Science and Preservation
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• v.10 no.3
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• pp.297-301
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• 2003

The hardness of corrugated packaging box decreased during storage period because of high humidity. Therefore, the strength-decreasing factor of corrugated packaging box had to be investigated to determine the compression strength of the corrugated packaging box. This study was conducted to define the characteristics of moisture absorption as well as compression strength of corrugated fiberboard. (1) The moisture content of the corrugated fiberboard was rarely influenced by the kinds of raw materials and water repellent. However, the moisture adsorption of the corrugated fiberboard was shown to be clearly affected by air temperature changes. (2) The moisture content of the corrugated fiberboard was significantly affected by relative humidity. The moisture adsorption of corrugated fiberboard was also greatly influenced by composition of raw materials rather than water repellent. The results indicated that the improvement of raw materials was more effective than the increase of water repellent of corrugated fiberboard to reduce the moisture adsorption of the corrugated fiberboard. (3) The vertical compression strength was significantly decreased with increasing relative humidity. The reduction rate of vertical compression strength was not charged with the increase of relative humidity, which was regardless of kinds of corrugated fiberboard. (4) For improving the strength of the corrugated packaging box, new technique should be found to develop better quality of raw materials. Moreover, the physical construction of corrugated packaging box should be clearly understood because the corrugated packaging box for the agricultural products was usually used for the circumstances of high humidity and low air temperature

• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.87-102
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• 2019

Pallancata Ag mine is located at the Ayacucho region 520 km southeast of Lima. The geology of mine area consists of mainly Cenozoic volcanic-intrusive rocks, which are composed of tuff, andesitic lava, andesitic tuff, pyroclastic flow, volcano clasts, rhyolite and quartz monzonite. This mine have about 100 quartz veins in tuff filling regional faults orienting NW, NE and EW directions. The Ag grades in quartz veins are from 40 to 1,000 g/t. Quartz veins vary from 0.1 m to 25 m in thickness and extend to about 3,000 m in strike length. Quartz veins show following textures including zonation, cavity, massive, breccia, crustiform, colloform and comb textures. Wallrock alteration features including silicification, sericitization, pyritization, chloritization and argillitization are obvious. The quartz veins contain calcite, chalcedony, adularia, fluorite, rutile, zircon, apatite, Fe oxide, REE mineral, Cr oxide, Al-Si-O mineral, pyrite, sphalerite, chalcopyrite, galena, electrum, proustite-pyrargyrite, pearceite-polybasite and acanthite. The temperature and sulfur fugacity ($f_{s2}$) of the Ag mineralization estimated from the mineral assemblages and mineral compositions are ranging from 118 to $222^{\circ}C$ and from $10^{-20.8}$ to $10^{-13.2}atm$, respectively. The relatively low temperature and sulfur-oxygen fugacities in the hydrothermal fluids during the Ag mineralization in Pallancata might be due to cooling and/or boiling of Ag-bearing fluids by mixing of meteoric water in the relatively shallow hydrothermal environment. The hydrothermal condition may be corresponding to an intermediate sulfidation epithermal mineralization.

• Tunnel and Underground Space
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• v.32 no.1
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• pp.59-77
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• 2022

Currently, the design reference temperature of the buffer material for disposing of high-level radioactive waste is less than 100℃, so if the heat dissipation capacity of the buffer material is improved, the spacings of the disposal tunnel and the deposition hole in the repository can be reduced. First of all, this study tries to analyze the criteria for thermal-hydraulic-mechanical performance of the buffer materials and to investigate the researches regarding the enhanced buffer materials with improved thermal conductivity. First, the thermal conductivity should be as high as possible and is affected by dry density, water content, temperature, mineral composition, and bentonite type. the organic content of the buffer material can have a significant effect on the corrosion performance of a canister, so the organic content should be low. In addition, hydraulic conductivity of the buffer material should be less than that of near-field rock and swelling pressure should be appropriate for buffer materials to function properly. For the development of enhanced buffer materials, additives such as sand, graphite, and graphite oxide are typically used, and a thermal conductivity can be greatly improved with a very small amount of graphite addition compared to sand.

• Journal of Conservation Science
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• v.37 no.6
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• pp.807-820
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• 2021

A study on the Joseon Dynasty's furnace walls, excavated from south Korea, was conducted to identify the correlations and differences of the furnace walls found in Jeolla and Gyeongsang regions. Three ruins in the Jeolla region and two in the Gyeongsang region were selected for the analysis. The results showed a layer change depending on the degree of plasticity and difference in the number of layers and particle phase. Furthermore, although the temperature to be subjected to heat was divided into 1300℃ and 1100℃, it was not a phenomenon that appeared according to the region. Additionally, analysis result of major components revealed that the TiO₂ content of most samples does not exceed 1wt%, This means that the furnace did not smelt iron sand or smelted it into low-titanium sand. This study indicated a slight similarity between the furnace walls found in the two regions, and the correlation was determined based on the nature of the ruins, raw materials of the metals ores, and composition of the raw materials constituting the furnace walls.

• Journal of the Korean Regional Science Association
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• v.39 no.3
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• pp.3-12
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• 2023

The issue to be discussed is set as the relationship between urban fragmentation and urban heat phenomena. The fragmentation is recognized as a negative form that commonly occurs in the process of urbanization. The purpose of this study is to examine the relationship between urbanization entropy and heat phenomenon by looking at the five major cities in Korea. The employed methods are InVEST Urban Cooling Model and MSPA (Morphological Spatial Pattern Analysis) by using the meteological data for the July 2018. The major results are as follows; First, a low rank correlation(rho=-0.3) is found in the relation between entropy and Cooling Capacity Index (CCi). Second, a very high level of rank correlation is observed between entropy and Average Temperature(℃)(rho=0.9). The implications are that 1) a city with a large degree of sprawling development can have a negative effect on urban heat phenomena; 2) the composition of land use including dispersion and concentration in non-urbanized areas, which has the characteristics of open space, can affect the urban thermal environment. Due to the limited number of case studies, it is appropriate to understand that a possibility, not generalization, is observed between entropy and heat phenomena in urbanized areas.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.145-151
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• 2023

In order to extend shelf life for rockfish fillets by modified atmosphere packaging (MAP), different package atmospheres were compared in the product quality preservation. Firstly, CO₂ solubility was measured at 0, 5, 10, and 15℃ to be incorporated into the mathematical model to predict the volume and CO₂ concentration of the package at expected storage temperature. The CO₂ solubility given in Henry's constant decreased with temperature to be fitted with a linear equation. Then air packaging as control and four MAP conditions of 100 g fillets were prepared and stored for duration of 5 days at 10℃ to compare them in the quality preservation effect. Four MAP conditions employed were CO₂(60):O₂(30):N₂(10), CO₂(60):O₂(0):N₂(40), CO₂(30):O₂(30):N₂(40) andCO₂(30):O₂(0):N₂(70). MAP conditions with high CO₂ concentration inhibited total aerobic bacteria, and the conditions containing O₂ led to low TVB-N. MAP of CO₂(60):O₂(30):N₂(10) was found to be the best condition for rockfish fillet preservation considering total aerobic bacteria growth and nitrogenous volatiles production.

• Journal of the Society of Disaster Information
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• v.10 no.4
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• pp.583-597
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• 2014

Fire caused by heater has various causes as many as the types of heater. also, lots of damage of human life and property loss are caused, since annually continuous fire accident by heater in traditional market is frequently occurring. There are not many cases of fire due to heater in most of residential facilities such as general house, apartments, etc., because they are supplied with heating boiler, however the restaurant, store and office of the market, sports center, factory, workplace, etc. still use heater, e.g. oilstove, electric heater, etc., so that they are exposed to fire hazard. Also, when investigating the number of fire due to heater, it was analyzed to occur in order of home boiler, charcoal stove, oilstove, gas heater/stove, electric stove/heater, the number of fire per human life damage was analyzed in order of gas heater/stove, oil heater/stove, electric heater/stove, briquette/coal heater. Also, gas and oil related heater were analyzed to have low frequency, however, with high fire intensity. Therefore, this research aimed at considering more scientific fire inspection and identification approach by reenacting and reviewing fire outbreak possibility caused by combustibles' contact and conductivity under the normal condition and abnormal condition in respect of ignition hazard, i.e. minimum ignition temperature, carbonization degree and heat flux along with it, due to oilstove and electric stove, which are still frequently used in public use facility, traditional market, and, of which actual fire occurrence is the most frequent. As the result of reenact test, ignition hazard appeared very small, as long as enough heat storage condition is not made in both test objects(oilstove/electric stove), however carbonization condition was analyzed to be proceeded per each part respectively. Eventually, transition to fire is the ignition due to heat storage, so that it was analyzed to ignite when minimum heat storage temperature condition of fire place is over $500^{\circ}C$. Particularly, in case of quartz pipe, the heating element of electric stove, it is rapidly heated over the temperature of $600^{\circ}C$ within the shortest time(10sec), so that the heat flux of this appears 6.26kW/m2, which was analyzed to result in damage of thermal PVC cable and second-degree burn in human body. Also, the researcher recognized that the temperature change along with Geometric View Factor and Fire Load, which display decrease of heat, are also important variables to be considered, along with distance change besides temperature condition. Therefore, the researcher considers that a manual of careful fire inspection and identification on this is necessary, also, expects that scientific and rational efforts of this research can contribute to establish manual composition and theoretical basis on henceforth fire inspection and identification.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.2
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• pp.319-344
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• 2015

A seasonal characteristic of marine environment and fish assemblages in the coastal waters of Jeju Island were determined using samples collected by a trammel net in from 2012 to 2013. Annual mean temperature and salinity were $18.8^{\circ}C$, 33.7psu (2012) and $18.8^{\circ}C$, 33.8psu (2013) which shows stable water mass. nutrient concentrations represent that dissolved inorganic nitrogen (DIN) ranged from 0.030 to 0.217mg/L, dissolved inorganic phosphorus (DIP) from 0.002 to 0.010mg/L, and silicate ($SiO_2$) from 0.096 to 0.292mg/L. Chlorophyll a concentrations of phytoplankton ranged from 0.905 to $1.125{\mu}g/L$ were appeared the highest in summer and the lowest in winter. Suspended Solid(SS) concentrations ranged from 1.200 to 2.100mg/L (mean, 1.634mg/L) were appeared the highest in autumn and the lowest in spring. During the survey period, a total of 83 species (48 families and 12 orders) of fishes were identified, Perciformes and Scorpaeniformes accounted for 63.9% of the total number. The number of species was higher in summer than in winter, showing a peak in summer at 57 species and a low in winter at 47 species. The number of individuals and the biomass peaked in summer at 694 individuals and 151.9kg, and were the lowest in autumn at 466 individuals and 106.5kg. The diversity index, evenness index and richness index were appeared 2.92~3.14, 0.75~0.83 and 7.06~8.56 at each stations. the dominance index were appeared highest in spring and summer, were appeared the lowest in winter and autumn. The Filefish (Stephanolepis cirrhifer), Bluestriped angelfish (Chaetodontoplus septentrionalis), Marbled rockfish (Sebastiscus marmoratus), Rabbit fish (Siganus fuscescens), Blackfin sweeper (Pempheris japonica) were dominant species, which occurred abundantly during the entire survey period. The subtropical fishes were identified total of 41 species (49.4%) and the number of species was higher in summer at 29 (50.9%) species and a low in winter at 20 (42.6%) species. The dominant species of subtropical fishes were appeared Bluestriped angelfish, Blackfin sweeper, Rabbit fish, Scarbreast tuskfish (Choerodon azurio), Ballonfish (Diodon holocanthus), Flagfish (Goniistius zonatus), Blue-spotted boxfish (Ostracion immaculatus) in study sites. The subtropical fishes of species, individual and biomass showed significant correlation with environmental factors (Chlorophyll a, DIN, DIP, $SiO_2$) in almost all sampling sites.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.110-122
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• 1996

The n-3 family fatty acids containing ${\alpha}$-linolenic acid(18:3, ALA) have been known as physiological activation materials such as inhibitory effects on the incidence of hyper-tension, coronary heart disease and cancers as well as the control of senilc dementia. Although a lot of ALA(about $63\%$) are contained in perilla oil, it has not been commercialized yet because the purification technique of the ALA has not been well established. The procedure of purification of ALA from perilla oil was saponified with 1 N-KOH /ethanol and then saturated and low level unsaturated fatty acids were removed by low-temperature crystallization method. The concentrated unsaturated fatty acids (containing about $75\%$ ALA) went down through the silver nitrate-impregnated silica column chromatography for separation of high purity of ALA. The results obtained we Fraction B, C and D contained ALA more than $85.5\%$(recovery, >$88.9\%,\;95.4\%$(recovery, >$54.4\%$) and $99.9\%$(recovery, >$31.5\%$) in purity, respectively. Seed oil content of the tested varieties were ranged from 34.8 to $54.1\%$ with $45.3\%$ of varietal means. The major omega fatty acids contained in the oil were oleic acid(n-9) $15.2\%$, linoleic acid(n-6) $13.9\%$ and linolenic acid(n-3) $63.1\%$ in the mean value. Varietal variation of n-9, 6 and 3 fatty acids ranged of $9.5\~21.4\%,\;9.1\~20.4\%$ and $50.6\~70.5\%$ respectively. Unsaturated fatty acid were averaged $92.2\%$ of seed oil in fatty acid composition. The ratios of n-6 to n-3 ranged of $0.13\~0.34\%$($0.22\%$ in mean value). The highest n-3 fatty acid variety was Yecheonjong being $70.5\%$. The lowest variety in ratios of n-6 to n-3 was Goseongjong being $0.13\%$. Oil content showed positive correlation with stearic acid and linolenic acid, while the negative correlation with oil content and linoleic acid. On the other hand, A significant negative correlation were showed between linolnic acid and the ratios n-6/n-3 fatty acid, saturated fatty acid. Saturated fatty acid was highly correlated with unsaturated fatty acid negatively being $r= -0.723^{**}$.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.503-509
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• 1991

Action of a cyclodextrin glycosyltransferase (CGTase) produced from alkalophilic Bacillus sp. No.4 was studied in a solution containing starch and sucrose to prepare glycosyl sucrose syrup with good sweetness and antidecaying properties of teeth. In the initial stage of the reaction the CGTase produced cyclodextrin, however, the cyclodextrin disappeared and glycosyl sucrose was formed with the lapse of reaction time. The best proportion of sucrose to starch for prodution of glycosyl sucrose was about 1 : 1. The optimum pH and temperature of the coupling reaction was pH 6.0 and $60^{\circ}C$, respectively. Main composition of glycosyl sucrose syrup prepared with 20% starch and 20% sucrose was sucrose 18%, glucosyl sucrose ($G_{2}F$) 15.3% and maltosyl sucorse ($G_{3}F$) 11.3%. And glucose, maltose and maltotriose were produced very little. Smaller amounts of acid and insoluble glucan were formed in the syrup by Streptococcus mtans OMZ176 than in the sucrose. Therefore, the prepared glycosyl sucrose sucrose syrup is expected to prevent teeth from decaying.