• Food Science of Animal Resources
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• v.30 no.3
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• pp.495-503
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• 2010

Analyses were conducted to estimate the effect of quality grade on the carcass characteristics, physico-chemical and sensory traits of Longissimus dorsi in Hanwoo. A total of 42,113 carcasses were selected on the basis of five quality grades (grade $1^{++}$, $1^+$, 1, 2, and 3) and an additional 258 samples of Longissimus dorsi were used to evaluate the beef quality. The increase in quality grade from grade 3 to grade $1^{++}$ was significant (p<0.05) for carcass weight (from 338.7 kg to 387.2 kg), backfat thickness (from 7.45 mm to 12.23 mm) and marbling score (from 1.09 to 8.31). In contrast, significantly decreased levels of meat color, fat color, texture and maturity were apparent with increasing quality grade (p<0.05). Increasing quality grade was also correlated with significant increases (p<0.05) in crude fat contents (from 3.57% to 25.68%) and water holding capacity (from 52.41% to 58.03), and a decrease of the Warner-Bratzler shear force from 8.29 kg to 2.83 kg. The highest $L^*$ value (41.53) and highest cooking loss (22.11%) were observed with grade $1^{++}$ and 3 beef, respectively. There was no difference observed on $pH_{24}$ (5.53 to 5.66) among the quality grades, which were within the normal range. Sensory evaluation experiments revealed that quality grades were associated with significantly altered (all p<0.05) tenderness, juiciness, flavor, and overall acceptability. The crude fat contents showed significant correlation with juiciness (r=0.59), tenderness (r=0.71), flavor (r=0.55), and overall acceptability (r=0.69). The lower sensory trait scores were related to higher WBs. Grade $1^+$ Hanwoo beef had a significantly higher WBs and lower fat contents when compared to grade $1^{++}$ Hanwoo beef (p<0.05).

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.16-36
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• 1984

It is very important in forestry to study the shear strength of weathered granitic soil, because the soil covers 66% of our country, and because the majority of land slides have been occured in the soil. In general, the causes of land slide can be classified both the external and internal factors. The external factors are known as vegetations, geography and climate, but internal factors are known as engineering properties originated from parent rocks and weathering. Soil engineering properties are controlled by the skeleton structure, texture, consistency, cohesion, permeability, water content, mineral components, porosity and density etc. of soils. And the effects of these internal factors on sliding down summarize as resistance, shear strength, against silding of soil mass. Shear strength basically depends upon effective stress, kinds of soils, density (void ratio), water content, the structure and arrangement of soil particles, among the properties. But these elements of shear strength work not all alone, but together. The purpose of this thesis is to clarify the characteristics of shear strength and the related elements, such as water content ($w_o$), void ratio($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$), and the interrelationship among related elements in order to decide the dominant element chiefly influencing on shear strength in natural/undisturbed state of weathered granitic soil, in addition to the characteristics of soil hardness of weathered granitic soil and root distribution of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands. For the characteristics of shear strength of weathered granitic soil and the related elements of shear strength, three sites were selected from Kwangju district. The outlines of sampling sites in the district were: average specific gravity, 2.63 ~ 2.79; average natural water content, 24.3 ~ 28.3%; average dry density, $1.31{\sim}1.43g/cm^3$, average void ratio, 0.93 ~ 1.001 ; cohesion, $ 0.2{\sim}0.75kg/cm^2$ ; angle of internal friction, $29^{\circ}{\sim}45^{\circ}$ ; soil texture, SL. The shear strength of the soil in different sites was measured by a direct shear apparatus (type B; shear box size, $62.5{\times}20mm$; ${\sigma}$, $1.434kg/cm^2$; speed, 1/100mm/min.). For the related element analyses, water content was moderated through a series of drainage experiments with 4 levels of drainage period, specific gravity was measured by KS F 308, analysis of particle size distribution, by KS F 2302 and soil samples were dried at $110{\pm}5^{\circ}C$ for more than 12 hours in dry oven. Soil hardness represents physical properties, such as particle size distribution, porosity, bulk density and water content of soil, and test of the hardness by soil hardness tester is the simplest approach and totally indicative method to grasp the mechanical properties of soil. It is important to understand the mechanical properties of soil as well as the chemical in order to realize the fundamental phenomena in the growth and the distribution of tree roots. The writer intended to study the correlation between the soil hardness and the distribution of tree roots of Pinus rigida Mill. planted in 1966 and Pinus rigida ${\times}$ taeda in 199 to 1960 in the denuded forest lands with and after several erosion control works. The soil texture of the sites investigated was SL originated from weathered granitic soil. The former is situated at Py$\ddot{o}$ngchangri, Ky$\ddot{o}$m-my$\ddot{o}$n, Kogs$\ddot{o}$ng-gun, Ch$\ddot{o}$llanam-do (3.63 ha; slope, $17^{\circ}{\sim}41^{\circ}$ soil depth, thin or medium; humidity, dry or optimum; height, 5.66/3.73 ~ 7.63 m; D.B.H., 9.7/8.00 ~ 12.00 cm) and the Latter at changun-long Kwangju-shi (3.50 ha; slope, $12^{\circ}{\sim}23^{\circ}$; soil depth, thin; humidity, dry; height, 10.47/7.3 ~ 12.79 m; D.B.H., 16.94/14.3 ~ 19.4 cm).The sampling areas were 24quadrats ($10m{\times}10m$) in the former area and 12 in the latter expanding from summit to foot. Each sampling trees for hardness test and investigation of root distribution were selected by purposive selection and soil profiles of these trees were made at the downward distance of 50 cm from the trees, at each quadrat. Soil layers of the profile were separated by the distance of 10 cm from the surface (layer I, II, ... ...). Soil hardness was measured with Yamanaka soil hardness tester and indicated as indicated soil hardness at the different soil layers. The distribution of tree root number per unit area in different soil depth was investigated, and the relationship between the soil hardness and the number of tree roots was discussed. The results obtained from the experiments are summarized as follows. 1. Analyses of simple relationship between shear strength and elements of shear strength, water content ($w_o$), void ratio ($e_o$), dry density (${\gamma}_d$) and specific gravity ($G_s$). 1) Negative correlation coefficients were recognized between shear strength and water content. and shear strength and void ratio. 2) Positive correlation coefficients were recognized between shear strength and dry density. 3) The correlation coefficients between shear strength and specific gravity were not significant. 2. Analyses of partial and multiple correlation coefficients between shear strength and the related elements: 1) From the analyses of the partial correlation coefficients among water content ($x_1$), void ratio ($x_2$), and dry density ($x_3$), the direct effect of the water content on shear strength was the highest, and effect on shear strength was in order of void ratio and dry density. Similar trend was recognized from the results of multiple correlation coefficient analyses. 2) Multiple linear regression equations derived from two independent variables, water content ($x_1$ and dry density ($x_2$) were found to be ineffective in estimating shear strength ($\hat{Y}$). However, the simple linear regression equations with an independent variable, water content (x) were highly efficient to estimate shear strength ($\hat{Y}$) with relatively high fitness. 3. A relationship between soil hardness and the distribution of root number: 1) The soil hardness increased proportionally to the soil depth. Negative correlation coefficients were recognized between indicated soil hardness and the number of tree roots in both plantations. 2) The majority of tree roots of Pinus rigida Mill and Pinus rigida ${\times}$ taeda planted in erosion-controlled lands distributed at 20 cm deep from the surface. 3) Simple linear regression equations were derived from indicated hardness (x) and the number of tree roots (Y) to estimate root numbers in both plantations.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.253-263
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• 2011

This study was conducted to gain preliminary data for restoration and management of constructed small-scale ponds in paddy fields through analysis of their physicochemical and biological properties. A field survey was performed at 13 small-scale ponds located in paddy fields from August 2009 to October 2010. Structural properties, water quality, soil characteristics and fish fauna were measured. Results showed that small-scale ponds without frames might lose their function over time because of crumbling walls. Therefore, it is necessary for these ponds to have frames for soil protection and sustainable maintenance. Chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) concentration were higher than the water quality standard for agricultural water in small-scale ponds. In particular, TN concentration was 8.03 mg $L^{-1}$ and over 8 times the water quality standard because of the presence of livestock such as cows and pigs in the study areas. Sand, organic matter and available phosphorus contents of soil in small-scale ponds was 53.4${\pm}$16.6%, 21.8${\pm}$9.74 g $kg^{-1}$ and 12.8${\pm}$7.59 mg $kg^{-1}$, respectively indicating that sand and available phosphorus contents were suitable for plants in small-scale ponds, but organic matter contents was somewhat low in newly constructed small-scale ponds, and would take some time to stabilize for plant growing. Fish fauna was not diverse with only 4 species at all sites surveyed. Collected fishes share a common feature that they all inhabit paddy fields or canals with shallow water depth. In this study, all ponds were not linked to the streams and canals around them. It appears that connection to adjacent streams was the major factor controlling fish fauna in small-scale ponds. The results of statistical analysis were classified into three groups. Factor 1 was 26.3%, which shows a structural properties such as area and depth of small-scale pond. As for factor 2, it appears on 20.1%, showing water quality like a TP, suspended solids (SS) and COD. Small-scale ponds were classified into three groups by factor scores. Group I consisted of 6 small-scale ponds, which were larger than the others. Group III had higher water quality than the others. We conclude that the most important points to be considered for restoration and management of small-scale ponds is connection with adjacent streams or ditches and depth and size of the small-scale pond.

• Economic and Environmental Geology
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• v.31 no.3
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• pp.185-199
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• 1998

Hydrogeochemical and environmental isotope studies were undertaken for various kinds of water samples collected in 1995-1996 from the Bugok geothermal area. Physicochemical data indicate the occurrence of three distinct groups of natural water: Group I ($Na-S0_4$ type water with high temperatures up to $77^{\circ}C$, occurring from the central part of the geothermal area), Group II (warm $Na-HCO_{3}-SO_{4}$ type water, occurring from peripheral sites), Group III ($Ca-HCO_3$ type water, occurring as surface waters and/or shallow cold groundwaters). The Group I waters are further divided into two SUbtypes: Subgroup Ia and Subgroup lb. The general order of increasing degrees of hydrogeochemical evolution (due to the degrees of water-rock interaction) is: Group III$\rightarrow$Group II$\rightarrow$Group I. The Group II and III waters show smaller degrees of interaction with rocks (largely calcite and Na-plagioclase), whereas the Group I waters record the stronger interaction with plagioclase, K-feldspar, mica, chlorite and pyrite. The concentration and sulfur isotope composition of dissolved sulfate appear as a key parameter to understand the origin and evolution of geothermal waters. The sulfate was derived not only from oxidation of sedimentary pyrites in surrounding rocks (especially for the Subgroup Ib waters) but also from magmatic hydrothermal pyrites occurring in restricted fracture channels which extend down to a deep geothermal reservoir (typically for the Subgroup Ia waters). It is shown that the applicability of alkaliion geothermometer calculations for these waters is hampered by several processes (especially the mixing with Mg-rich near-surface waters) that modify the chemical composition. However, the multi-component mineral/water equilibria calculation and available fluid inclusion data indicate that geothermal waters of the Bugok area reach temperatures around $125^{\circ}C$ at deep geothermal reservoir (possibly a cooling pluton). Environmental isotope data (oxygen-18, deuterium and tritium) indicate the origin of all groups of waters from diverse meteoric waters. The Subgroup Ia waters are typically lower in O-H isotope values and tritium content, indicating their derivation from distinct meteoric waters. Combined with tritium isotope data, the Subgroup Ia waters likely represent the older (at least 45 years old) meteoric waters circuated down to the deep geothermal reservoir and record the lesser degrees of mixing with near-surface waters. We propose a model for the genesis and evolution of sulfate-rich geothermal waters.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.518-524
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• 1995

In this study physicochemical characteristics such as crude lipid, crude protein and total sugar contents have been analyzed with samples taken at different developing stages and growing sites, Bongsan-ri(steam-roasted green tea) and Buchun-ri(roasted green tea) area. Leaf area of new leaf was larger in Buchun-ri(7.23cm$^2$) than in Bongsan-ri(6.93cm$^2$). Variation of leaf area by the developing stages was the largest at between stage II (May 5) and stage III(May 18). Dry matters ratio of tea leaf were 26.3% in Bongsan-ri and 26.6% in Buchun-ri. Water content, ash, water-soluble matters, total sugar content of green tea sampled in Bongsan-ri and Buchun-ri were 5.6, 6.1, 33.1, 4.6 and 6.2, 5.8, 35.2, 2.8%, respectivley. Crude lipid, total nitrogen and water-soluble protein, inorganic matters content of green tea sampled in Bongsan-ri and Buchun-ri were 2.8, 5.1, 1.1, 2.56 and 2.2, 5.7, 1.0, 2.34%, respectively. At the later developing stages crude lipid, total sugar contents were increased, whereas total nitrogen had low content. Vitamin C, Vitamin E and Vitamin A content of green tea produced in Bongsan-ri and Buchun-ri area were 413mg%, 71.8mg%, 32.15IU and 311mg%, 52.3mg%, 25.68IU, respectively. Vitamin C and Vitamin E content were increased toward the later sampling stages. Water-soluble matters and water-soluble protein content of green tea prepared by the steam-roasted method and the roasted method were increased by 0.11, 0.13 and 0.09, 0.08%, respectively, compared to unroasted check. Crude lipid content of green tea prepared by the steam-roasted method and the roasted method were decreased by 0.13 and 0.24%, respectively. Total nitrogen content of green tea prepared by the steam-roasted method and the roasted method was changed 0.019 and 0.036%, respectively and total nitrogen content showed minute different between two methods.

• Journal of Korea Foresty Energy
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• v.17 no.1
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• pp.56-70
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• 1998

This study was carried out to investigate the structural characteristics of kraft lignin and the wood degrading characteristics, the productivity of ligninolytic enzymes and the enzymatic degradation of kraft lignin by white-rot fungi. To purify kraft lignin, precipitation of kraft pulping black liquors of pitch pine meal was done by titration with lN $H_{2}SO_{4}$ reaching to pH 2, and isolation of the precipitates done by centrifugation. The isolated precipitates from pitch pine were redissloved in lN NaOH, reprecipitated by titration with lN $H_{2}SO_{4}$, washed with deionized water, and kept ofr analysis after freeze drying. Fractionation of the precipitates in solution by successive extraction with $CH_{2}Cl_{2}$ and MeOH, and the fractionates were named SwKL, SwKL I, SwKL II, and SwKL III for pitch pine kraft lignin. The more molecular weights of kraft lignin increased, the less phenolic hydroxyl groups and the more aliphatic hydroxyl groups. Because as the molecular weights increased, the ratio of etherified guaiayl/syringyl(G/S ratio) and the percentage were increased. The spectra obtained by 13C NMR and FTIR assigned by comparing the chemical shifts of various signals with shifts of signals from autherized ones reported. The optimal growth temperature and pH of white-rot fungi in medium were $28^{\circ}C$ and 4.5-5.0, respectively. Especially, in temperature and pH range, and mycelial growth, the best white-rot fungus selected was Phanerochaete chrysosporium for biodegradation. For the degradation pathways, the ligninolytic fungus jcultivated with stationary culture using medium of 1% kraft lignin as a substrate for 3 weeks at $28^{\circ}C$. The weight loss of pitch pine kraft lignin was 15.8%. The degraded products extracted successively methoanol, 90% dioxane and diethyl ether. The ether solubles were analyzed by HPLC. Kraft lignin degradation was initiated in $\beta$-O-4 bonds of lignin by the laccase from Phanerochaete chrysosporium and the degraded compounds were produced from the cleavage of $C\alpha$-$C\beta$ linkages at the side chains by oxidation process. After $C\alpha$-$C\beta$ cleavage, $C\alpha$-Carbon was oxidized and changed into aldehyde and acidic compounds such as syringic acid, syringic aldehyde and vanilline. And the other compound as quinonemethide, coumarin, was analyzed. The structural characteristics of kraft lignin were composed of guaiacyl group substituted functional OHs, methoxyl, and carbonyl at C-3, -4, and -5 and these groups were combinated with $\alpha$ aryl ether, $\beta$ aryl ether and biphenyl. Kraft lignin degradation pathways by Phanerochaete chrysosporium were initially accomplished cleavage of $C\alpha$-$C\beta$ linkages and $C\alpha$ oxidation at the propyl side chains and finally cleavage of aromatic ring and oxidation of OHs.

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.476-481
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• 2002

The Physical and sensory characteristics of muffins prepared with flavonoids such as ferulic acid and p-hydroxybenzoic acid were evaluated for the development of functional foods using these flavonoids. The solubilities of ferulic acid and p-hydroxybenzoic acid were over 1% in water and the solutions showed a good thermal stability. However, 1% ferulic acid and p-hydroxybenzoic acid solution showed a color change during heating. The volume and maximum height of the control muffin were the greatest among the muffin groups. The volume of the muffins decreased with the increase of flavonoid concentration. The volumes of muffins with p-hydroxybenzoic acid were smaller than those of muffins with ferulic acid. The L, a and b values on crust and crumb of the muffin groups were not significantly different. The chemical flavor, bitterness and after taste of the muffins prepared with ferulic acid were stronger than those of the control muffins. Savory flavor and sweetness of the muffins with ferulic acid were weaker than those of the control muffins. The muffins with p-hydroxybenzoic acid were not significantly different from the control muffins in the appearance, flavor, taste, texture and overall acceptability. These results demonstrated that p-hydroxybenzoic acid may be useful as an additive to muffin.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.389-396
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• 2018

The Kori-1 Nuclear Power Plant (NPP), WH 2-Loop Pressurized Water Reactor (PWR) operated for approximately 40 years in Korea, was permanently ceased on June 18, 2017. To reduce worker exposure to radiation by reducing the dose rate in the system before starting main decommissioning activities, the permanently ceased Kori-1 NPP will be subjected to full system decontamination. Generally, the range of system decontamination includes Reactor Pressure Vessels (RPV), Pressurizer (PZR), Steam Generators (SG), Chemical & Volume Control System (CVCS), Residual Heat Removal System (RHRS), and Reactor Coolant System (RCS) piping. In order to decontaminate these systems and equipment in an effective manner, it is necessary to evaluate the influence of the flow characteristics in the RCS during the decontamination period. There are various methods of providing circulating flow rate to the system decontamination. In this paper, the flow characteristics in Kori-1 NPP reactor coolant according to RHR pump operation were evaluated. The evaluation results showed that system decontamination using an RHR pump was not effective at decontamination due first to impurities deposited in piping and equipment, and second to the extreme flow unbalance in the RCS caused deposition of impurities.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.55-60
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• 1991

This study was carried out to obtain the effects of soil environment and characteristics on the growth and yield of young rice seedling. Twenty four rice fields were selected among the labor saving mechanization complex, and the growth statu s and various soil characteristics were investigated The young rice seedling planted soils were located at the range of elevation 5m to 210m, and the average water holding days was 5.1 days, and drainage class were mainly moderately well to imperfectly. The plant height on 30th day after machine transplanting were higher and the tiller numbers were smaller at the higher clay contents at moderately well and imperfectly drained soils. In case of sandy loam soils, the better the drainage class, the higher plant and more tillers. Soil hardness was lower in sandy loam, and the bulk densities of loam, silty clay loam and poorly drained soils were lower than the other fields. There were not differences of soil chemical properties between the soil textural groups but organic matter content were higher in poorly drained soils. The rice yields of young seedling planted fields were negatively correlated to soil bulk density and highly significantly correlated to the exchangeable calcium contents of the soils. The average yield of young rice seedlings was 487kg/10a, 2.5% higher than semi-adult rice seedling of 475kg/10a.

• Journal of Environmental Health Sciences
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• v.37 no.1
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• pp.29-43
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• 2011

The seasonal characteristics of atmospheric particulate matter (PM) were evaluated through the measurement of $PM_{10}$ (particles with an aerodynamic diameter of less than 10 ${\mu}m$) and $PM_{2.5}$ (particles with an aerodynamic diameter of less than 2.5 ${\mu}m$) collected in the downtown area of Iksan city over roughly two weeks in each season of 2004. During the sampling period, 54 samples of $PM_{10}$ and $PM_{2.5}$ were collected and then measured for mass concentrations of PM and its water-soluble inorganic ion species. The concentrations of $PM_{10}$ and $PM_{2.5}$ were highly variable on a daily time scale in all seasons, especially in fall. Annual concentrations of $PM_{10}$ and $PM_{2.5}$ were $54.7{\pm}21.6\;{\mu}g/m^3$ and $34.0{\pm}13.4\;{\mu}g/m^3$, respectively. The daily concentrations of the analyzed ions similarly showed a pronounced variation, although a difference between seasons existed. Among them, $SO_4^{2-}$, $NO_3^-$ and $NH_4^+$ were the most abundant ions in all seasons, contributing up to 32% of $PM_{10}$ and 39% of $PM_{2.5}$. The contribution of $SO_4^{2-}$ and $NO_3^-$ showed a seasonal variation, as $SO_4^{2-}$ was the highest during spring and summer and $NO_3^-$ was the highest during fall and winter. Non-seasalt $SO_4^{2-}$ and $NO_3^-$ were found to exist mainly as neutralized chemical components of $(NH_4)_2SO_4$ and $NH_4NO_3$ due to the high concentration of $NH_4^+$ in PM samples, which were a major form of airborne PM in all seasons. Seasonal characteristics of $PM_{10}$ and $PM_{2.5}$ in Iksan were described in relation to the temporal variations of daily concentration of PM and its inorganic ion species including inter-particle reactions.