• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.503-510
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• 2000

To improve the milling condition of brown rice a continuous type conditioning equipment was developed. To validate the performance of this machine the experimental operation was done at Sa-cheon RPC(Rice Processing Complex) using short grain rough. The initial moisture contents of brown rice were 15.0∼16.5%(w.b) and the flow rate of brown rice passing through the conditioner were 4,370kg per hour. The moisture content differences of brown rice between conditioned and non-conditioned were showed within 0.5%(w.b) This results means that the water injected to brown rice were absorbed to the surface of brown rice evenly. The moisture contents of conditioned treated milled rice were showed slightly higher than that of non-conditioned ones but it was considered that the conditioning process did not affected the weight increasing of milled rice by water supply. For initial moisture contents of 15.0∼16.5%(wb) brown rice it was found that the proper water supply rate was 0.115(cc-water)/(kg·%-brown rice) and the increments of whole rice were 2.2% compared to the non-conditioned ones. it was considered that the conditioning process did not influenced the whiteness of milled rice because the whiteness differences between conditioned and non-conditioned milled rice were negligible. About 18% of electric power which drives the abrasive type rice milling machine was saved at 0.115(cc-water)/(kg·%-brown rice) of water supply rate.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.135-143
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• 1998

In order to study the general characteristics of reservoir and stream sediments, various analysis tests were conducted. Water contents and ignition loss were measured to know the primary sediment characteristics. The COD, total phosphorus and nitrogen were contained for the determination of organic substance content. For the purpose of establishing the contamination degree of heavy metals, some heavy metal contents were investigated. In heavy metal contents, reservoir sediments showed somewhat higer value than stream sediments. As a result, the reservoir sediment content of all analysis items were higher than stream sediment.

• Journal of Food Hygiene and Safety
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• v.14 no.3
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• pp.305-318
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• 1999

This study were conducted to estimate the values of the heavy metal in the fresh water fish and shellfish collected from fish market. The levels of the heavy metal were determined in a total of 319 samples of 11 species of the fresh water fish and 14 species of the shellfish by mercury analyzer and atomic absorption spectrophotometer. The results of this study were summerized as follows; The average contents of the heavy metal in the fresh water fish were Pb 0.075, Hg 0.05:3, Cd 0.002, Cr 0.135, Fe 8.695, Mn 1.078, Zn 9A91, Cu 0.548 mg/ kg. The average contents of the heavy metal in the shellfish were Pb 0.059. Hg 0.007, Cd 0.146, Cr 0.147, Fe 40.808, Mn 7.738, Zn 13.943, Cu 2.7:31 mg/kg. Being compared the average contents of the heavy metal of the fresh water fish with those of shellfish, the average contents of Cd, Fe, Mn, Cu in the shellfish were significantly higher than in the fresh water fish(P<0.001). Depending on the sampling areas, the average contents of the heavy metal were different by districts. The contents of the heavy metal were changed with the seasons(P<0.05).

• Journal of environmental and Sanitary engineering
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• v.5 no.1
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• pp.65-72
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• 1990

To study on the water quality of domestic purifier, twenty four samples of clean water by purifier and the raw water(tap water) were tested for biological and physico-chemical examination and were checked for style of purification and the period elapsed after changing of purification medium. The results were as follows; Biological and physico-chemical findings of raw water were not exceeded standard values. Average number of general bacteria,2.coli and pH in clean water were significantly higher than that of raw water(respectively, p<0.01), but mean contents of turbidity, chloride, nitrate and iron in clean water were significantly lower than that of raw water(respectively, p<0.01). In general count of bacteria and E.coli, a half of the clean water of ceramic filter and roverse osmosis style were exceeded standard values for drinking water. All of the pH of the ion exchange style clean water were exceeded standard values. But other findings were within standard values. In average bacterial counts and physico-chemical findings of clean water by purification style of purifier, clean water of ion exchange style purifier were lowest number of general bacteria and not detected in 2. coli. But other items were highest. The longer period elapsed after changing of purification medium were the higher contents of biological and physico-chemical findings of clean water.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.17-25
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• 2012

In this study, dielectrical constant of the ground was measured using TDR method and correlated with water contents and density of ground. In order to evaluate the applicability as a cavity exploration, model experiments were carried out to analyze the effects of cavity size on the dielectrical constant. Test result indicated that dielectrical constant of the ground tended to linearly increase with the increase in water contents and density, which can be represented in a certain relational expression. Also, the dielectrical constant of ground varied sensitively with the cavity size of ground. The results conclude that the dielectrical constant, water contents and density of the ground proved to have a correlation among them, and the dielectrical constant is expected to be a basic data on cavity exploration.

• Journal of Ocean Engineering and Technology
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• v.20 no.1 s.68
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• pp.7-15
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• 2006

In this research, the behavior characteristics of cement mixing lightweight soil (CMLS) for recycling of dredged soil in the Nakdong River estuary are experimentally investigated. CMLS is composed of the dredged soil from Nakdong River estuary, cement, and air foam. For this purpose, uniaxial compression tests are carried out for artificially prepared specimens of CMLS, with various initial water contents, cement contents, and mixing ratio of dredged soils. The experimental results of CMLS indicated that the compressive strength is strongly influenced by the cement contents, rather than water contents and air foam. Compressive strength of CMLS increased with an increase in cement content, while it decreased with an increase in water content and air foam content. It was also found that the modulus of deformation E50 was in a range of 44 to 128 times greater than the value of uniaxial compressive strength, cured in 28 days.

• Korean Journal of Remote Sensing
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• v.33 no.4
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• pp.411-422
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• 2017

This research aims to analyze spectral reflectance of intertidal zone and its changes under various environmental conditions. We sampled sand of Mongsanpo tidal flat, Korea, and measured its spectral reflectance by using a spectroradiometer under various water contents, compositions and granularity. We also simulated the reflectance of Landsat 7 ETM+ and compared it with an actual satellite data. Five locations were selected for sampling from the coastline towards the ocean. Grain size diminished stepwise from the coastline to ocean direction, while spectral reflectance differed with wavelength. Water contents lowered the overall reflectance especially at the water absorption bands. Spectral reflectance data were then converted into the simulated one by using Landsat 7 ETM+ spectral reflectance function to be compared with the actual Landsat 7 ETM+ images. It showed the decrease of the spectral reflectance due to the increase of moisture contents from seashore towards the ocean. It is shown that Landsat 7 ETM+ imagery can be efficient to extract moisture contents in the tidal flat while compositional analysis needs satellite sensors with much higher spectral resolution.

• Ocean and Polar Research
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• v.35 no.4
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• pp.273-280
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• 2013

The proximate composition, free amino acid composition and mineral contents from Undariopsis peterseniana were determined, and the antioxidant activities of ethanol (EtOH) and hot water extracts of U. peterseniana were investigated using DPPH (1,1-diphenyl-1-picrylhydrazyl), ABTS (2,2'- azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging effects and reducing power. The contents of moisture, ash, protein, lipid and carbohydrate were 12.5%, 23.1%, 9.7%, 0.2% and 54.5%, respectively, and alginic acid content was 12.3%. The major free amino acid contents were alanine, phenylalanine, aminoethanol, valine, glutamic acid and phosphoserine. Ca (1589.1 mg) was the largest mineral followed by Na (344.6 mg), Mg (74.3 mg), Zn (10.2 mg) and Fe (1.5 mg). The total phenolic contents of EtOH and hot water extracts were exhibited at 15.7 and 4.3 mg GAE/g sample, respectively. The antioxidant activity of EtOH extract exhibited strong ABTS and DPPH radical scavenging activities with reducing power, and hot water extract also demonstrated strong ABTS radical scavenging effects. Therefore, the results of this study suggest that U. peterseniana contained an abundance of naturally occurring nutrients (free amino acids and minerals), and the strong antioxidant activities of EtOH and hot water extracts from U. peterseniana could be good sources of natural antioxidants for healthcare products.

• Journal of the Korean Chemical Society
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• v.6 no.2
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• pp.176-197
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• 1962

Seasonal variations of chemical constituents of estuarine water at a definite station of the tidal flat in Guang Yang inlet have been determined for two days a month. The range and mean of the annual variations are as follows:Tidal variations through a year are as follows:1. Although the tidal value of pH is almost constant during one tidal cycle, it raises abruptly 0.1-0.2 intervals of pH value during the first period of flood.2. The lower values of chlorinity, magnesium and calcium contents have been determined the nearer the slack after ebb, and slightly higher during the first period of flood tide than the last of ebb. The tidal change of calcium contents is more remarkable than of magnesium.3. The higher per cent saturation values of dissolved oxygen, sometimes higher than 100 per cent, re determined the nearer the slack after ebb.4. The total nitrogen contents, relatively poor, varies accidentally during one tidal cycle, whereas phosphate-P and silicate-Si are rich at the slack after ebb and increase proportionally to the mixing percentage of fresh water. The average values, 52.2 and 18.5 of Si/P and N/P are greater than of the normal.5. The acid soluble iron contents, lower in winter than in summer, is also varies accidentally during one tidal cycle and the magnitude of the variation is large.6. The chemical composition considered from the value of Ca/Cl or Mg/Cl of estuarine water varies according to the chlorinity even at the high chlorinity of 18-19%.

• Journal of Environmental Impact Assessment
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• v.16 no.1
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• pp.69-77
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• 2007

This study has been conducted to assess blackish-water phenomena in Dam reservoir. To searching for the reason, we survey physical changes in reservoir and analyze metal and organic content in particulate materials and water. The blackish-water phenomena in lake A are occurred with turbidity increases in turnover season irregularly. It was reported on 6 Jan. 2005 weakly and the water column mixed with 35~40m depth and water temperature shows $7^{\circ}C$. The turbidity of AD and AM site increased up to 20NTU. Especially, AN site shows 27NTU, such a result makes that Dam manager conclude it to blackish-water phenomena. The results of sequential extraction analysis show that over 80% of Al, Cr and Fe is existed in residual form in sediment. On the other hand, the most part of Mn shows exchangeable and carbonates form, which have a good possibility of release to water column. Mn contents in pore waters of the sediment samples are also found to be ~4 times higher than Fe contents. The metal contents in pore water of different dam sites are in order of AN (Fe: 9.98, Mn: 40.6) > AD(8.33, 37.5) > DD(1.91, 2.55). According to the results of extracted organic materials from sediment, humic substances is occupied with over 85% in total organic carbon including 23~45% of humic acid (HA) and 0.9~8.5% of fulvic acid (FA). However, HA content in pore water is not detectable while FA contents, acid-soluble humic fractions is higher than that of sediment(10~15%). which indicating that FA is a main humic components affecting water color. The color unit per DOC of FA in pore waters of different dam sites are found to be higher in lake A than lake D. From the results, it could be suggested that blackish-water phenomena of lake A are mainly arise from higher concentration of Mn and water soluble organic fractions (e.g., FA) released from sediments as well as the strength of turnover in Dam reservoir.