• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.135-148
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• 2017

Response Surface Methodology (RSM), which is combining with Plackett-Burman design and Box-Behnken experimental design, was applied to optimize the ratios of the nutrient components for carotenoid production by Rhodobacter sphaeroides PS-24 in liquid state fermentation. Nine nutrient ingredients containing yeast extract, sodium acetate, NaCl, $K_2HPO_4$, $MgSO_4$, mono-sodium glutamate, $Na_2CO_3$, $NH_4Cl$ and $CaCl_2$ were finally selected for optimizing the medium composition based on their statistical significance and positive effects on carotenoid yield. Box-Behnken design was employed for further optimization of the selected nutrient components in order to increase carotenoid production. Based on the Box-Behnken assay data, the secondary order coefficient model was set up to investigate the relationship between the carotenoid productivity and nutrient ingredients. The important factors having influence on optimal medium constituents for carotenoid production by Rhodobacter sphaeroides PS-24 were determined as follows: yeast extract 1.23 g, sodium acetate 1 g, $NH_4Cl$ 1.75 g, NaCl 2.5 g, $K_2HPO_4$ 2 g, $MgSO_4$ 1.0 g, mono-sodium glutamate 7.5 g, $Na_2CO_3$ 3.71 g, $NH_4Cl$ 3.5g, $CaCl_2$ 0.01 g, per liter. Maximum carotenoid yield of 18.11 mg/L was measured by confirmatory experiment in liquid culture using 500 L fermenter.

• Journal of Animal Environmental Science
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• v.16 no.3
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• pp.227-236
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• 2010

This study was conducted to develop an measuring system and method for fermentation degree of liquid swine manure by visible ray. The constituent changes of liquid swine manure were examined. pH gradually increased with time, but EC gradually decreased. Malodor strength decreased gradually with aeration treatment with time. Control needed more time to decrease malodor strength than aeration treatment. In aeration treatment, there was no germination of seeds (radish, chinese cabbage) up to 6 weeks and germination rate at 15th week was over 50%. However, in control, there was no germination up to end of experiment. Circular chromatography method showed that there was change after 10th week in aeration treatment but there was no change up to end of experiment in control. As a result, the fermentation degree of liquid swine manure would have relations among pH, EC, germination rate, malodor concentration, and reaction of circular chromatography. The simple analytical instrument for liquid swine manure consisted of a tungsten halogen and deuterium lamp for light source, a sample holder, a quartz cell, spectrometer for spectrum analyzer, a malodour measuring device, a software, etc. Results showed that the simple analytical instrument that was developed can approximately predict the fermentation degree of liquid swine manure by visible ray. Generally, the experiment proved that the simple analytical instrument was reliable, feasible and practical for analyzing the fermentation degree of liquid swine manure.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.97-102
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• 1980

Cladosporium fulvum, Aspergillus ochraceus, Aspergillus terreus and N-1 (unidentified species) were cultured on the artificial media containing sucrose as a carbon source at 20, 25 and $30^{\circ}C$ for 10 to 12 days. The lipids in the felts were extracted with chloroform-methanol mixture and the class composition and fatty acids of the lipid were determined. The summarized results are as follows 1. The average felts produced by each species per 100 ml of media were $3.82{\pm}0.30g$ for Cl. fulvum, $2.62{\pm}0.23g$ for Asp. ochraceus, $4.24{\pm}0.25g$ for Asp. terreus and $4.62{\pm}0.10g$ for N-1. Their crude fat contents $27.5{\pm}1.61%,\;50.47{\pm}1.00%,\;46.6{\pm}1.59%$ and 33.78 % and the fat coefficient 6.92, 8.88, 13.01 and 10.28, respectively. 2. The lipids produced by these species were mainly composed of triglyceride and the next free fatty acid in Cl. fulvum and N-1 and phospholipid Asp. ochraceus and Asp. terreus. 3. The major fatty acids of the lipids were in order of oleic, palmitic, linoleic and stearic acids in Asp. ochraceus, Asp. terreus and Cl. fulvum and linoleic, palmitic, oleic and stearic acid in N-1. The total percentage contents of these major fatty acids were over 98 % the former and over 95 % the latter. 4. The constituent fatty acids of the lipid were changed depending on the incubation temperature but hardly found a certain tendency except linoleic acid which was higher at lower temperature. 5. The total percentages of unsaturated fatty acids in the lipids were $50{\sim}60%$ and comparatively higher at lower incubation temperature.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.1-22
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• 2012

The classification scheme of estuaries can be divided into two categories: qualitative classification based on geomorphic characteristics and quantitative classification based upon the physical properties of water body. While simple and intuitive scheme of the former is difficult to quantify, the latter is not easy to apply due to the lack of data. A classification scheme based on morphological convergence is very promising because it only requires easily accessible data such as width and depth of channels, as well as it can characterize estuaries in terms of tidal propagation. Thus, this paper examines the classification scheme based on estuarine morphological convergence using depth and width data obtained from 19 major Korean estuaries. Morphological convergence for each estuary was estimated with the estuarine length, width and depth data to get the convergence parameters, which includes the degree of funneling ${\nu}$ and the dimensionless estuarine length $y_0$. The transfer function ${\xi}({\nu},ky)$ is then deduced analytically from 1D depth-integrated hydrodynamic momentum equation and continuity equation for estuarine shapes. Tidal response of each estuary is finally calculated using ${\nu}$, $y_0$ and ${\xi}({\nu},ky)$ for comparison and classification. The 19 Korean estuaries were classified into three groups: tidal amplitude-dominated estuaries with standing wave-like tidal response (group 1), current-dominated estuaries with progressive wave-like tidal response (group 2), and the intermediate group (group 3) between groups 1 and 2. The sensitivity analysis revealed that uncertainties in determining the estuarine length can have a critical effect upon the results of classification, which indicates that the reasonable determination of the estuarine length is of critical importance. Once the estuarine length is feasibly determined, depth-convergence can be neglected without any negative effect on the classification scheme, which has an important ramification on the wide applicability of the classification scheme.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.283-293
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• 2018

This study was performed to analysis of chemical constituent in Polygonum multiflorum root (PMR) by different dry methods (hot-air dry, shade dry, and freeze dry). The results are summarized as followings; major free sugar were detected fructose, glucose, and sucrose in dried PMR based on various dry methods. The highest content of free sugars was found in freeze dried PMR. The four organic acids were detected in dried PMR by HPLC analysis. The content of oxalic acid in shade dried PMR was higher than the dried PMR by different dry methods. The content of total amino acid and essential amino acids were high in the orders of freeze drying > shade drying > hot-air drying. The potassium and magnesium levels of freeze dried PMR was significantly higher than the other drying method of PMR. Whereas the calcium and sodium levels were higher in hot-air dried PMR. The major fatty acids were determined the linoleic acid in PMR by different dry methods.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.399-407
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• 2009

Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.5
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• pp.581-589
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• 2021

With the recent increase in the introduction of micro-electric vehicles in Korea, interest in micro-electric vehicle user satisfaction is increasing to revitalize related markets. In this paper, a basic study was conducted on the development of public services using micro-electric vehicle based on the constituent factors of user satisfaction. The survey includes: ① 'Analytic Hierarchy Process (AHP) for selecting the priority factors of user satisfaction of micro-electric vehicles', ② 'A survey of micro-electric vehicles image' to collect data in advance for providing users' preferences and transportation services for micro-electric vehicles, ③ In order to investigate the user satisfaction level of users who actually operated micro-electric vehicles, the order of 'user satisfaction survey of micro-electric vehicle drivers' was conducted. In the Analytic Hierarchy Process (AHP) analysis, it was found that users regarded as important in the order of 'user utilization data', 'vehicle movement data', and 'charging service data'. In the micro-electric vehicle image survey, users perceived micro-electric vehicles more positively in terms of "safety", 'durability', 'Ride comfort', 'design', 'MOOE (Maintenance and other operating expense)', and 'environment-friendly' when comparing micro-electric vehicles with electric motorcycles. In the survey on the user satisfaction of micro-electric vehicle drivers, the use of micro-electric vehicle did not directly affect work performance efficiency, and there was an experience of being disadvantaged on the road due to the size of the micro-electric vehicle, and driving in a cluster of micro-electric vehicle for outdoor advertisements. The city's public relations effect was great, but it was concerned about safety. In the future, based on the results of this study, we plan to build a user satisfaction structural equation model, preemptively discover feedback R&D for micro-electric vehicle utilization services in the public field, and actively seek to discover new public mobility support services.

• Korean Journal of Heritage: History & Science
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• v.50 no.4
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• pp.122-147
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• 2017

The Jungsandong sites are distributed across quartz and mica schist formations in Precambrian, and weathering layers include large amounts of non-plastic minerals such as mica, quartz, felspar, amphibole, chlorite and so on, which form the ground of the site. Neolithic pottery from Jungsandong exhibits various brown colors, and black core is developed along the inner part for some samples, and sharp comb-pattern and hand pressure marks can be observed. Their non-plastic particles have various composition, size distribution, sorting and roundness, so they are classified into four types by their characteristic mineral compositions. I-type (feldspar pottery) is including feldspar as the pain component or mica and quartz. II-type (mica pottery) is the combination of chloritized mica, talc, tremolite and diopside. III-type (talc pottery) is with a very small amount of quartz and mica. IV-type (asbestos pottery) is containing tremolite and a very small amount of talc. The inner and outer colors of Jungsandong pottery are somewhat heterogeneous. I-type pottery group shows differences in red and yellow degree, depending on the content of feldspar, and is similar to III-type pottery. II-type is similar to IV-type, because its red degree is somewhat high. The soil of the site is higher in red and yellow degree than pottery from it. The magnetic susceptibility has very wide range of 0.088 to 7.360(${\times}10^{-3}$ SI unit), but is differentiated according to minerals, main components in each type. The ranges of bulk density and absorption ratio of pottery seem to be 1.6 to 1.7 and 13.1 to 26.0%, respectively. Each type of pottery shows distinct section difference, as porosity and absorption ratio increase in the order as follows: I-type (organic matter fixed sample) < III-type and IV-type < I-type < II-type (including IV-type of IJP-15). The reason is that differences in physical property occur according to kind and size of non-plastic particles. Although Jungsandong pottery consists of mixtures of various materials, the site pottery has a geological condition on which all mineral composition of Jungsandong pottery can be provided. There, it is thought that raw materials can be supplied from weathered zone of quartz and mica schist, around the site. However, different constituent minerals, size and rock fragments are shown, suggesting the possibility that there can be more raw material pits. Thus, it is estimated that there may be difference in clay and weathering degree.

• Journal of the Mineralogical Society of Korea
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• v.31 no.4
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• pp.267-275
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• 2018

The purposes of this study were to analyze the mineralogical characteristics of slaked lime used for wall repair of traditional buildings in Bagan, Myanmar and to evaluate the physical properties of lime plaster produced by the same method as Bagan region. In the X-ray diffraction and thermal analysis of the Myanmar slaked lime, portlandite ($Ca(OH)_2$) and brucite ($Mg(OH)_2$) were detected as main constituent minerals, and a carbonate rock mainly composed of dolomite ($CaMg(CO_3)_2$) minerals may be used as a raw material to make slaked lime. The field-emission scanning electron microscope analysis showed that the Myanmar slaked lime was composed of irregularly shaped crystals of $0.5{\mu}m$ or larger and a small amount of $0.1{\mu}m$ of plate - like crystals. The size and uniformity of crystals in Myanmar lime is different from that of Korea slaked lime. This may be attributed to the effect of the mineral composition and the lime hydration method of Myanmar, which produces slurry by immersing the burnt lime in excess water for a long period of time. The compressive strength of the lime plaster in Myanmar resulted in a mean value of $1.13N/mm^2$ for the specimens cured for 28 days. The strength of the specimens with Bale juice was $1.03N/mm^2$, respectively. The lime is an air setting material that exhibits strength through long carbonation process. Therefore, it is necessary to evaluate physical properties according to curing period through long-term curing over 28 days in the future.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.1018-1027
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• 2019

Natural-derived protein-derived low molecular weight peptides have been known to have physiological activities such as antioxidant, hypertension relief, immunomodulation, pain relief and antimicrobial activity. In this study, the low-molecular peptides were produced using commercial proteases (alcalase, bromelain, flavourzyme, neutrase, papain, protamex), and the antioxidant activity (DPPH scavenging activity, superoxide radical scavenging activity, hydroxy radical scavenging activity, and metals chelation capacity), constituent amino acid and molecular weight of the peptide were analyzed. Enzyme reaction was performed by adding 50 g of chopped Ogae meat slurry and 2%(w/v) protein enzyme into the enzyme reactor for 2 h at a pH of 6 and a temperature of $60^{\circ}C$. The degree of hydrolysis(%) after the reaction ranged from $36.65{\pm}4.10%$ to $70.75{\pm}5.29%$. The highest degree of hydrolysis of protamex was 46.3%, and the highest value of papain hydrolysate was $70.75{\pm}5.29%$. On the other hand, alcalase hydrolysate showed the lowest value of $36.65{\pm}4.10%$. Bromelain-treated low molecular weight peptides showed the highest DPPH radical scavenging activity and the lowest scavenging activity of alcalase-treated peptides. Superoxide radical scavenging activity showed that bromelain treated low molecular peptide showed the highest radical scavenging activity of 50% or more. Hydroxyl radical scavenging activity ranged from about 16.73 to 69.16%, the highest among bromelain-treated low molecular peptides. $Fe^{2+}$ chelation abilities showed a distribution between about 17.85 to 47.84%. The chelation capacity of the hydrolysates was not significantly different without any difference to the enzymes used. The results of amino acid analysis showed differences between hydrolysates of alcalase, bromelain, flavourzyme, neutrase, papain, and protamex enzymes. The most amino acid was glutamic acid. The molecular weight distribution of the enzyme hydrolyzates was in the range of 300-2,000 Da, although the molecular weight distribution differed according to the treated enzymes.