• Journal of Korean Society for Geospatial Information Science
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• v.11 no.3 s.26
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• pp.23-34
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• 2003

Currently, the efficiency of GPS has been increased in the various precise survey like as the control survey and the navigation etc. Also, it is widely used in the deformation analysis of the structure, the measurement of the marine tides, the measurement of the river level and the topographic monitoring of seabed or riverbed by combined the measurement equipment for depth. In this study, we intend to increase in efficiency of the topographic monitoring of seabed or riverbed by combined with DGPS, RTK GPS and echo sounder. For this study, we defined the error correction of the echo sounder with the experiment of water tank which is considered the characteristic of estuary riverbed and then we developed the s/w for 3-dimensional monitoring of estuary riverbed and applied the s/w to field test and improved the various problems. On analyzing topography of estuary riverbed by combined GPS with echo sounder, the draught error which is yielded to change of length from the water surface by the movement of survey vessel to the end of the transducer was eliminated by geometrical rearrangement and we defined the correction formula $z=BM+SAH-DBR_{(i)}-DRT-ED$. The sounding error about the echo sounder and characteristic of estuary riverbed was found by understanding the relation of average diameter ind residual error and we defined correction formula, $Y=0.00474{\ast}ln(X)-0.0045$ by the regression analysis. and then we verified applicability of correction formula.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.421-426
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• 1999

This study was performed to evaluate the effect of persimmon vinegar on serum lipid components in the hypercholesterolemic Sprague-Dawley male rats. Forty rats were divided into four groups and fed diets containing l% cholesterol for 4 weeks. Experimental diets added to distilled water, 1.5%, 3%, and 7% persimmon vinegar(PV) as drinking water. Concentration of total cholesterol, LDL and HDL cholesterol, triglyceride in serum and activity of AST, ALT in serum were assayed. Average food intake, weight gain and FER of experimental rats were not significantly different by contents of persimmon vinegar. Concentration of total cholesterol and LDL cholesterol in serum were lowest in 7% persimmon vinegar group. However concentration of HDL cholesterol in serum was highest in 3% persimmon vinegar group. Concentration of triglyceride in serum was significantly lower in persimmon vinegar group than control group. Activities of AST and ALT in serum were lowest in 7% persimmon vinegar group. The results in this study suggest that persimmon vinegar is effective in lowering serum triglyceride level.

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.175-188
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• 2009

In this study, we developed an experimental method of the Charles' law applicable to school. Science textbooks and literatures on this principle were analyzed to extract factors utilized in organizing the experimental setup and method. A combined structure such as with a vial and a glass tube, the former of which is for deciding the total volume and the latter of which is for easy measurement of volume, was better in measurement of volume with temperature rather than a simple structure such as syringe. Use of graduated cylinder as a water bath to control the temperature showed advantage in cooling time than using other bath of larger volume such as a beaker. A liquid drop was used as a plug in the glass tube. This plug has little resistance with the glass wall when the gas volume changes. Water as a liquid drop in the glass tube had a significant effect in volume change of gas due to evaporation, especially in the beginning of the measurement. Glycerol showing negligible effect in volume change was used. This method took about one hour and produced a good linear relationship between the temperature and volume of gas with $R^2$ = 0.999 and absolute zero temperature = $-216.7\;{^{\circ}C}$. The Charles' law experiment developed in this study can be performed with appropriate adjustment of procedure considering the purpose of the curriculum of science and chemistry subject at each school level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.480-486
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• 2012

To evaluate of biological activity of Chambirum ($Amaranthus$ $lividus$) $in$ $vitro$ and $in$ $vivo$, we investigated the free radical scavenging activity of its extracts $in$ $vitro$ and the effect of lyophilized powder on the serum lipid profile of rats fed cholesterol. ABTS, DPPH, and NO radical scavenging activities were tested from water and 80% ethanol extracts of Chambirum, and biological activities of the ethanol extracts were significantly higher than the water extracts. The total lipid and total cholesterol content of serum, atherogenic index (AI), and cardiac risk factor (CRF) were decreased significantly for the groups fed with a 5% and 10% supplement of Chambirum powder (HCA1 and HCA2) in comparison with the group fed cholesterol (HC). Triglyceride content decreased drastically in the HCA2 group, while its content was not decreased in the other group. HDL-cholesterol content was elevated in the HCA1 and HCA2 groups, but was not significantly different to the supplemented amount of Chambirum powder. GPT and ${\gamma}$-GTP activities were decreased significantly in the groups fed with Chambirum powder compared to the HC group. And the content of the lipid peroxide level was the same trend. Therefore, these results give evidence that Chambirum might be useful in the control of induced disorders by dietary cholesterol and/or lipids.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.729-741
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• 2012

Among the methods of precipitation data acquisition, a rain gauge station has a distinctive advantage of direct measurement of rainfall itself, but multiple stations should be installed in order to obtain areal precipitation data required for hydrological analysis. On the other hand, a rainfall radar may provide areal distribution of rainfall in real time though it is an indirect measurement of radar echoes on rain drops. Rainfall radars have been shown useful especially for forecasting short-term localized torrential storms that may cause catastrophic flash floods. CAPPI (Constant Altitude Plan Position Indicator), which is one of the several types of radar rainfall image data, has been provided on the Internet in real time by Korea Meteorological Administration (KMA). It is one of the most widely available rainfall data in Korea with fairly high level of confidence as it is produced with bias adjustment and quality control procedures by KMA. The objective of this study is to develop an improved way to extract quantitative rainfall data applicable to even very small watersheds from CAPPI using CIVCOM, which is a new image processing method based on a vector-based scheme proposed in this study rather than raster-based schemes proposed by other researchers. This study shows usefulness of CIVCOM through comparison of rainfall data produced by image processing methods including traditional raster-based schemes and a newly proposed vector-based one.

• Food Science and Preservation
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• v.24 no.6
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• pp.771-777
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• 2017

Although Doenjang is a representative traditional fermented food in Korea, made mainly from soybeans, it has been classified into a food group identified as having high sodium in the National Health and Nutrition Examination. It is necessary to develop a low sodium Doenjang to prevent the excessive sodium intake which may cause various diseases. However, the development of Doenjang with low sodium, without significant changes on quality, is an ongoing challenge. Therefore, the experiment was designed to reduce the salt content of the soaking water to 12.5-45%. The pH, saltiness. moisture, sodium, color, amino-type nitrogen, free amino acids and constituent amino acids composition of Doenjang were investigated to determine the effect of this salt reduction on the sensory quality of Doenjang. The reduction of sodium did not affect the pH, moisture and saltiness, and this changed maintained the same range as the control. The sodium content was reduced proportionally, and the amino acid nitrogen level was 500 mg%. Therefore, this study considered that a reduction of 25% of salt in the soaking water does not affect the quality of the Doenjang while reducing the sodium content of the final Doenjang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.423-429
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• 2009

This study was conducted to investigate the effects of pine (Pinus densiflora) needle extracts on hepatic antioxidative system in rats fed high-cholesterol diet. Eight-week old Sprague Dawley rats were divided into four groups; normal diet group (CON), 0.5% cholesterol diet group (0.5% CHOL), 0.5% cholesterol diet and pine needle extracts prepared by using hot water group (HOT water), and 0.5% cholesterol diet and pine needle extracts prepared by using sub-supercritical $CO_2$ group (Sub-supercritical). The serum ALP, AST, and ALT activities were increased by 0.5% cholesterol diet supplementation, but treatment with pine needle extracts showed decrease compared with 0.5% CHOL group. The SOD activity in liver at 0.5% cholesterol diet group was more decreased than control group while Sub-supercritical group had significantly higher SOD activity than 0.5% CHOL group. Moreover, groups with pine needle extracts supplementation had higher level of GPx in liver than 0.5% cholesterol diet group. These results suggest that pine needle extracts increased antioxidative activities.

• International Journal of Industrial Entomology and Biomaterials
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• v.32 no.2
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• pp.80-89
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• 2016

The effects of Cudrania tricuspidata (CT) extract on markers of osteoporosis were examined in ovariectomized rats. We classified 26 rats into five groups and provided a pellet chow diet and tap water throughout the 27-wk experimental period. During the last 15 wk, we added oral injections to each group as follows: sham-operated (SHAM, n=4) and ovariectomized-control (OVX, n=5) with distilled water, alendronate with 10 mg/kg/d of alendronate sodium (ALEN, n=5), CT (CT100, n=6) with 100 mg/kg/d of CT, and CT (CT300, n=6) with 300 mg/kg/d of CT. After the experimental period, blood, urine, and micro-CT images were assessed. The CT100 and OVX groups did not show any significant differences in urinary n-terminal telopeptide (NTx) (p<0.05 ), but with increases in CT concentration, the NTx level was slightly reduced. Serum osteocalcin was significantly higher in the CT groups than in all other groups (p<0.05 ). Notably, the serum calcium levels of all groups were within the normal range, but urinary calcium levels in the CT groups were significantly lower than the OVX group (p<0.05 ). In addition, the CT groups exhibited higher trabecular BMD than the OVX groups while showing similar BMD to the ALEN group (p<0.05 ). The Tb.Th of the ALEN group was lower than all other groups. Based on the overall analysis of results, CT prevented bone loss by inhibiting bone resorption and enhancing bone formation. Although alendronate showed a similar effect in preventing bone loss, it did so by solely inhibiting bone resorption, and its long-term use reportedly causes paradoxical effects such as hip fractures. Thus, for osteoporosis induced by ovariectomy, we conclude that CT extract is an effective natural treatment without severe side effects.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.330-337
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• 2021

3D printing is not only at the fundamental study and small-scale level, but has recently been producing buildings that can be inhabited by people. Buildings require a lot of cost and labor to work on the form work, but if 3D printing is applied to the building, the construction industry is received attention from technologies using 3D printing as it can reduce the construction period and cost. 3D printing technology for buildings can be divided into structural and non-structural materials, of which 3D printing is applied to non-structural materials. Because 3D printing needs to be additive manufacturing, control such as curing speed and workability is needed. Since cement mortar has a large shrinkage due to evaporation of water, cement polymer dispersion is used to improve the hardening speed, workability, and adhesion strength. The addition of polymer dispersion to cement mortar improves the tensile strength and brittleness between the cement hydrate and the polymer film. Cement mortar using polymer materials can be additive manufacturing but it has limited height that can be additive manufacturing due to its high density. When light-weight materials are mixed with polymer cement mortar, the density of polymer cement mortar is lowered and the height of additive manufacturing, so it is essential to use light-weight materials. However, the use of EVA redispersible polymer powder and light-weight materials, additional damage such as cracks in cement mortar can occur at high temperatures such as fires. This study produced a test specimen incorporating light-weight materials and EVA redispersible polymer powder to produce exterior building materials using 3D printing, and examined flame resistance performance through water absorption rate, length change rate, and cone calorimeter test and non-flammable test. From the test result, the test specimen using silica sand and light-weight aggregate showed good flame resistance performance, and if the EVA redispersible polymer powder is applied below 5%, it shows good flame resistance performance.

• The Korea Journal of Herbology
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• v.36 no.2
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• pp.1-9
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• 2021

Objectives : Gossypium arboreum (cotton) is traditionally used to treat various health disorders. However, anti-amnesic effect of G. arboreum has not been reported. The objective of this study was to investigate in-vivo the anti-amnesic effects along with in vitro antioxidant and acetylcholinesterase (AChE) inhibition potential in G. arboreum seed essential oil. Methods : The essential oil of G. arboreum obtained by solid phase microextraction (SPME) techniques were identified by gas chromatography-mass spectroscopy (GC-MS). 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay were performed to determine the antioxidant activity at various concentrations (312.5, 625, 1250, 2500, 5000, 10000 ㎍/㎖. Y-maze, passive avoidance and Morris water maze tests were carried out to evaluate improved effect on scopolamine (1 mg/kg)-induced memory dysfunction at the dose level of 50, 100 and 200 mg/kg. Donepezil (5 mg/kg) was used as a positive drug control. We performed acetylcholinesterase (AChE) activity assay in ex vivo. Results : Five volatile compounds were identified in G. arboreum. The assays of DPPH and ABTS revealed that G. arboreum increased antioxidant activity in a dose-dependent manner. G. arboreum ameliorated the percent of spontaneous alternation in the Y-maze test, shortened step-through latency in the passive avoidance test, and increased swimming time in the target zone in the Morris water maze test. In addition, G. arboreum inhibited the AChE activity. Conclusions : Based on these findings, G. arboreum may aid in the prevention and treatment of learning and memory-deficit disorders through antioxidant and AChE inhibitory activities.