• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.2
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• pp.99-110
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• 2005

Characteristics of concentrations of total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) pollutant in percolated water at four paddy field sites (Soro, Odong, Munui, and Boeun) were investigated by a nonparametric test. Percolation rate measurement and percolated water sampling were taken during irrigation periods at $5{\sim}10$ day intervals. The normality of percolation rate and pollutant concentrations were examined using histogram, boxplot, and the Kolmogorov-Smirnov (K-S) test. Pollutant concentrations in percolated water showed positively skewed distribution. The median concentrations of pollutant were 1.91 mg/L for TN, 0.021 mg/L for TP, and 6.6 mg/L for COD, which were lower than its arithmetic mean concentrations by $35\%$ for TN, $36\%$ for TP, and $13\%$ for COD. The median concentrations of TN and TP differed significantly among sample sites according to the Kruskal-Wallis test. However, median concentrations were not significantly different among month except for TN and TP of Soro and COD of Odong. The percolation load of pollutants during irrigation periods in the study area were estimated at $3.12{\sim}7.75\;kg/ha$ for TN, $0.033{\sim}0.155\;kg/ha$ for TP, and 10.7 kg/ha for COD, which were much lower than respective values reported in Japan.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.231-238
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• 2001

To investigate the underground structure of shallow water, Han-river near Yangsou-Ri, high resolution hydroacoustic measurements were carried out for the engineering design of railroad bridge. The acoustic source was a Boomer with an energy of 90 to 280J and in a frequency range up to about 16KHz. The reflected signals were received by using both traditional hydrophones(passive element) and a specially devised receiver unit(active element) mainly composed of piezofilms and preamplifier. They are connected to the "SUMMIT" data acquisition system(DMT-GeoTec company), where the sampling interval was set to 1/32㎳. The source position was continuously monitored by a precision DGPS system whose positioning accuracy was on the order of loom. For the quality control purposes, two different source-receiver geometries were taken. That is to say, the measurements were repeated along the profile everytime depending on the different source energy(175J, 280J), the receiving elements(passive, active) and two different source-receiver geometries. It was shown that the data resolution derived from a proper arrangement with the active hydrophone could be greatly enhanced and hence the corresponding profile section caused by the regular data processing system "FOCUS" accounted excellently for the underground formation below the shallow water.w the shallow water.

• International journal of advanced smart convergence
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• v.9 no.4
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• pp.16-25
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• 2020

The operation of a wastewater treatment plant (WWTP) is a complex task which requires to consider several aspects: adapting to always changing influent composition and volume, ensuring treated effluents quality complies with local regulations, ensuring dissolved oxygen levels in biological reaction tanks are sufficient to avoid anoxic conditions etc. all of it while minimizing usage of chemicals and power consumption. The traditional way of managing WWTPs consists in having employees on the field measure various parameters and make decisions based on their judgment and experience which holds various concerns such as the low frequency of data, errors in measurement and difficulty to analyze historical data to propose optimal solutions. In the case of activated sludge WWTPs, parts of the treatment process can be automated and controlled in order to satisfy various control objectives. The models developed by the International Water Association (IWA) have been extensively used worldwide in order to design and assess the performance of various control strategies. In this work, we propose to review most recent WWTP automation initiatives around the world and identify most currently used control parameters and control architectures. We then suggest a framework to select WWTP model, control parameters and control scheme in order to develop and benchmark control strategies for WWTP automation.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.831-839
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• 2010

The results of wet noodles added with 0, 1, 3, 5, and 7% freeze-dried maesangi powder demonstrate that the addition of maesangi powder up to 5% was desirable formation of noodles. The moisture contents of wet noodle 35.48~36.42%. As the added amount of maesangi powder increased, weight, volume, water absorption, and turbidity the wet noodle soup after cooking increased. Measurement of color changes between before and after cooking the wet noodles found that as the added amount of maesangi powder increased, the lightness and yellowness increased. Measurement of texture after boiling found that, hardness, chewiness and gumminess tended to increase as the amount of added maesangi powder increased whereas, springiness and cohesiveness were significantly different between the different samples. The results of the sensory evaluation showed that the 3%-added group was the best for color, flavor, and taste while the control groups had the best texture. For overall acceptability, the 3%-added group showed found the highest preference level. Measurement of the changes in total viable cells during storage at $5^{\circ}C$ for 18 days found that 6-days was the optimal storage period for the noodles from the control groups and added groups. As the storing period increased, the maesangi powder added groups showed slower propagation speed for viable cells compared to the control groups.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.155-165
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• 2014

In this study, using a complex of physical, chemical, and biological evaluation factors, the ecological vulnerability to climate change were evaluated at each river in the Nakdong river basin. First, runoff, sediment rate, and low flow discharge changes according to AIB climate change scenario using the SWAT model were simulated. Also, for the assessment of chemical and biological factors, 48 points that water quality monitoring sites and ecological health measurement points are matched with each other was selected. The water quality data of BOD and T-P and the biological data of IBI and KSI in each point were reflected in the assessment. Also, the future rise in water temperature of the rivers in Nakdong river basin was predicted, and the impact of water temperature rise on the fish habitat was evaluated. The top 10 most vulnerable points was presented through a summary of each evaluation factor. This study has a contribution to river restoration or management plan according to the characteristics of each river.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.1
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• pp.18-26
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• 2001

Landsat TM band ratio algorithms were made by in-water optical measurement data of each sampling points for water quality monitoring of coastal area using Landsat TM satellite data. The algorithm was derived from in-water optical reflectance data which was measuring by the PRR(profiling reflectance radiometer). And, in-water optical reflectance data were applied to Landsat TM bands. Relationship between in-water optical reflectance and pigments proposed by the ratio of TM band 1 and band 2 showed to as follows; $Y=3.8352{\times}(R(band\;1)/R(band\;2))^{-2.1978}$ ($R^2$=0.7069) and, relationship of the ratio of TM band 1 and band 3 as follows; $Y=23.288{\times}(R(band\;1)/R(band\;3))^{-1.5243}$ ($R^2$=0.8062). Calculated the upwelling radiance of water surface and radiance of TM showed the ratio of atmospheric effect. In the coastal area Rayleigh and Mie scattering of atmosphere is to make over 80% of normalized radiance of Landsat TM. In order to apply in-water algorithm obtained by PRR, we had to calculate the atmospheric effects at sampling site. And, the quantitative analysis of in-water components using Landsat TM data need the calibration of in-water algorithm and effective method of atmospheric correction.

• Clean Technology
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• v.27 no.2
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• pp.174-181
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• 2021

This study analyzed the groundwater quality characteristics according to the main source of pollution and quarter (season) by using data from the pollution exclusive monitoring network in the Gyeongsangnam-do area for five years (2013-2017). The main source of pollution was the industrial complex areas, waste mines, and sewage treatment facilities. The analysis items were field measurement items (water temperature, pH, electrical conductivity, dissolved oxygen, oxide reduction potential), positive ions, and negative ions. Water temperature and pH did not vary significantly according to the main source of pollution. In industrial complex areas, the value of electrical conductivity was the highest, and dissolved oxygen value was the lowest. The mean concentration of positive and negative ions was the largest in industrial complex areas, followed by sewage treatment facilities and waste mines. It was shown that the concentration of sodium ion was the highest in industrial complex areas and calcium ion in waste mines and sewage treatment facilities. The concentration of bicarbonate ion was the highest in all main sources of pollution. Water temperature, pH, and concentrations of cations and anions did not vary significantly from quarter to quarter. Of the water quality types, the Na-HCO₃ type accounted for the highest proportion, but the Na-Cl type, which has a high possibility of external contamination, accounted for about 20% of the total data in the pollution exclusive monitoring network.

• Journal of radiological science and technology
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• v.5 no.1
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• pp.55-62
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• 1982

Measurement of triiodothyronine($T_3$) concentration is useful for the diagnosic and treatment of thyroid gland diseases. Fundermental studies of measurement of $T_3$ concentration by radioimmunoassay were performed and values determined by commercially available kit, Coat-A-Count, Diagnostic Products Corporation. The optimal utilization of the radioimmunoassay in measuring $T_3$ concentrations is dependant not only on high quality performance of the assay, but also on their appropriate application to the clinical situation. These are several aspects that must be considered in every individual case. These include factors such as accurate pippeting in reagent preparation in the assay and through decanting to remove all visible moisture after incubation steps and so forth. In attempt to assess quality control of the radioimmunoassay of serum $T_3$, serum pools with high, medium, low $T_3$ concentrations were assayed for each of 5 samples. The results obtained with this study were as follow: 1. The coefficient of variation(C. V.) for the standard curve ranged between $0.2{\sim}3.5%$. 2. It was necessary that both incubation time and temperature should correctly be maintained all the in the assay performance. 3. The precison with the $T_3$ RIA procedure was good. 4. The measured values of serially diluted serum $T_3$ concentration with Ong/dl standard solution was proportional to the predicted values. However dilution curve of distilled water was not strait. 5. Calculated $T_3$ values of patient serum in normal group was $107.8{\pm}25.90ng/dl$ in male patient and $127.29{\pm}24.08ng/dl$ in female patient.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.2
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• pp.25-30
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• 2021

This study investigated how the indicators of quality control are improved by proficiency in the measurement of phosphate concentration. In addition, analysis equipments were to be compared to see if there were any differences in measurements depending on the type of analysis device. In order to find out the effect of the proficiency of the analyst on the analysis results, three analysts measured phosphate concentration seven times in accordance with the Korean water pollution test standards, and met the quality control indices if repeated more than five times. The limit of quantification for phosphate was calculated at 0.02 mg/L. If the analysis devices are different, the absorbance and concentration of the samples near the limit of quantification are statistically significant difference.

• Journal of Biosystems Engineering
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• v.40 no.2
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• pp.124-136
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• 2015

Purpose: Grain quality is a general concept that covers many characteristics, ranging from physical to biochemical and physiochemical properties. Rice aging during storage is currently a challenge in the rice industry, and is a complicated process involving changes in all of the above properties. Spectroscopic techniques can be used to obtain information on the quality of rice samples in a non-destructive manner. Methods: The objective of this review was to highlight the factors that contribute to rice quality and aging, and to describe various spectroscopic modalities, particularly vibrational and hyperspectral imaging, for the assessment of rice quality. Results: Starch and protein are the main components of the rice endosperm, and are therefore key factors contributing to eating and cooking quality. While the overall starch, protein, and lipid content in the rice grain remains essentially unchanged during storage, structural changes do occur. These changes affect pasting and gel properties, and ultimately the flavor of cooked rice. In addition, grain quality is significantly affected by growing and environmental conditions, such as water availability, temperature, fertilizer application, and salinity stress. These properties can be evaluated using spectroscopic techniques, and rice samples can be discriminated by using multivariate statistical analysis methods. Conclusion: Hyperspectral imaging and vibrational spectroscopy techniques have good potential for determining rice quality properties in a non-invasive manner, i.e., not requiring the introduction of instruments into the rice grain.