• Journal of Korean Society on Water Environment
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• v.36 no.2
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• pp.98-108
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• 2020

The purpose of this study was to evaluate water quality in Hapcheon dam via using the Hydrological Simulation Program-Fortran (HSPF) model and applied livestock reduction scenarios. Hapcheon dam watershed input data for the HSPF model were established using the stream, land use, digital elevation map and meteorological data and others. The HSPF model was calibrated and validated using the observed water quality data from 2000 to 2016. For water quality simulation, we calculated the generated and discharge loads of the population, livestock, industry and land use following the guideline provided by the Ministry of Environment. The pollutant data were obtained from National Institute of Environmental Research (NIER). The monthly discharge load were estimated by applying the delivery rate. The calibration and validation results showed that the annual mean BOD had a difference of 0.22 mg/L and an error of ±13 %, T-N had a difference of 0.66 mg/L and an error of ±16 % and T-P had a difference of 0.027 mg/L and an error of ±13 %. In order to evaluate the nonpoint pollutants management effects, we applied livestock reduction scenarios because livestock consists of the largest portion of pollutants. As a result of the 20 % of livestock reduction, BOD, T-N and T-P decreased by 3 %, 1 % and 3 %, respectively. When 40 % of livestock reduction was applied, BOD, T-N and T-P decreased by 5 %, 3 % and 4 %, respectively. Based on the results of this study, effective pollutant management methods can be applied to improve the water quality and achieve the target water quality of Hapcheon dam watershed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.12
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• pp.1831-1843
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• 2001

In this study, convective boiling tests were conducted for enhanced tube bundles. The surface geometry consists of pores and connecting gaps. Tubes with three different pore sizes (d$_{p}$ = 0.20, 0.23 and 0.27 mm) were tested using R-123 and R-l34a for the following range: 8 kg/m$^2$s G 26 kg/m$^2$s, 10 kW/m$^2$ q0 40 kW/m$^2$and 0.1 $\chi$ 0.9. The convective boiling heat transfer coefficients were strongly dependent on heat flux with negligible dependency on mass flux or quality. For the present enhanced geometry (pores and gaps), the convective effect was apparent. The gaps of the present tubes may have served routes for the passage of two-phase mixtures, and enhanced the boiling heat transfer. The convective effect was more pronounced at a higher saturation temperature. More bubbles will be generated at a higher saturation temperature, which will lead to enhanced convective contribution. The pore size where the maximum heat transfer coefficient was obtained was larger for R-l34a (d$_{p}$ = 0.27 mm) compared with that for R-123 (d$_{p}$ = 0.23 mm). This trend was consistent with the previous pool boiling results. For the enhanced tube bundles, the convective effect was more pronounced for R-134a than for R-123. This trend was reversed for the smooth tube bundle. Possible reasoning is provided based on the bubble behavior on the tube wall. Both the modified Chen and the asymptotic model predicted the present data reasonably well. The RMSEs were 14.3% for the modified Chen model and 12.7% for the asymptotic model.model.

• Microbiology and Biotechnology Letters
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• v.36 no.2
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• pp.121-127
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• 2008

A strain IDCC 9203 isolated from infant feces was identified as Lactobacillus johnsonii on the basis of 16S rDNA sequence analysis. L. johnsonii IDCC 9203 was highly resistant to acid (MRS broth at pH 2.3) and bile (MRS broth with 0.3% oxgall). The antibacterial activities of L. johnsonii IDCC 9203 was examined against Salmonella typhimurium KCTC 2054. The growth of S. typhimurium KCTC 2054 was inhibited by the cell-free culture supernatant (at pH 4.0) of L. johnsonii IDCC 9203 as well as by the respective control (MRS broth at pH 4.0). Antimicrobial effect against S. typhimurium KCTC 2054 of L. johnsonii IDCC 9203 was probably due to the lactic acid. By an in vitro cell adhesion model, L. johnsonii IDCC 9203 preincubated or coincubated with Caco-2 cells reduced the adhesion of S. typhimurium KCTC 2054 to Caco-2 cells by 74% or 47.1%, respectively. Also in an in vivo model, L. johnsonii IDCC 9203 was colonized in mice intestines which were disrupted by ampicillin treatment. Its proliferation in the mice intestines reduced abnormal salmonella growth from $10^9CFU/g$ feces to $10^5CFU/g$ feces as an indigenous level. The results obtained in this study suggest that L. johnsonii IDCC 9203 may be a potential probiotic strain.

• 한국해양학회지
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• v.26 no.2
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• pp.108-116
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• 1991

A production model was constructed by combining the production rate and biomass of Sargassum confusum measured at monthly intervals on the coast of Ohori, Korea, to estimate the algal production for a given period. The production for a certain period, e.g., for a year (P/SUB yr/), was calculated from the equation: P/SUB yr/ = .int.P/SUB t/$.$B/SUB t/dt, where pl and Bl are the production rate and biomass at time t. P/SUB l/ was considered as a function of temperature and light. Photosynthesis-Irradiance curves obtained from the in situ experiments were applied for P/SUB l/ Temperature and light intensity can be expressed as periodic functions of time (T, L=f(t)). Diurnal values of water temperature and light intensity at 3 m depth where S. confusum mainly found were substituted into the equation of P/SUB l/. Simulations using our models show that temperature was one of the most sensitive factors operating on the primary production. Thirty percent decrease of light intensity by cloud cover was estimated to decrease the annual production by 5%.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.389-400
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• 1988

The recent trend in multiple-use land management planning is using Model I and Model II formulations designed for timber activity scheduling problems. Numerous models hate been developed, with MUSYC(Johnson and Jones, 1979) being the first to incorporate both model structures. Currently the most popular computer program using both Model I and Model II is FORPLAN(Johnson and others, 1986). A Model I formulation requires fewer rows and provides more direct information on what happens to an acre from rotation to rotation. In some problems, Model II provides a much more compact problem matrix with much fewer columns and only a moderate increase in row number. In this paper we examined and evaluated their usefulness in comprehensive multiresource forest management planning.

• Environmental Engineering Research
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• v.20 no.1
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• pp.73-78
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• 2015

The aim of this study was to examine the phosphate (P) removal by quintinite from aqueous solutions. Batch experiments were performed to examine the effects of reaction time, temperature, initial phosphate concentration, initial solution pH and stream water on the phosphate adsorption to quintinite. Kinetic, thermodynamic and equilibrium isotherm models were used to analyze the experimental data. Results showed that the maximum P adsorption capacity was 4.77 mgP/g under given conditions (initial P concentration = 2-20 mgP/L; adsorbent dose = 1.2 g/L; reaction time = 4 hr). Kinetic model analysis showed that the pseudo second-order model was the most suitable for describing the kinetic data. Thermodynamic analysis indicated that phosphate sorption to quintinite increased with increasing temperature from 15 to $45^{\circ}C$, indicating the spontaneous and endothermic nature of sorption process (${\Delta}H^0=487.08\;kJ/mol$; ${\Delta}S^0=1,696.12\;J/(K{\cdot}mol)$; ${\Delta}G^0=-1.67$ to -52.56 kJ/mol). Equilibrium isotherm analysis demonstrated that both Freundlich and Redlich-Peterson models were suitable for describing the equilibrium data. In the pH experiments, the phosphate adsorption to quintinite was not varied at pH 3.0-7.1 (1.50-1.55 mgP/g) but decreased considerably at a highly alkaline solution (0.70 mgP/g at pH 11.0). Results also indicated that under given conditions (initial P concentration=2 mgP/L; adsorbent dose=0.8 g/L; reaction time=4 hr), phosphate removal in the stream water (1.88 mgP/g) was lower than that in the synthetic solution (2.07 mgP/g), possibly due to the presence of anions such as (bi)carbonate and sulfate in the stream water.

• Journal of Acupuncture Research
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• v.38 no.2
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• pp.140-145
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• 2021

Background: Aconitum sinomontanum Nakai (ASN) has been reported to have analgesic effects. In this study an animal model of pharmacopuncture using ASN (100-500 mg/kg) was examined. Methods: Sprague-Dawley (SD) rats (n = 40) were randomly assigned to ASN-Low (1 mg/mL, 1.8 mL, ASN-L), ASN-Intermediate (5 mg/mL, 1.8 mL, ASN-M), ASN-High (10 mg/mL, 1.8 mL, ASN-H), negative control (0.2 mL normal saline), and positive control (0.2 mL 0.5% lidocaine) groups. All experiments were administered to the rats' left hind leg. The analgesic response was assessed by monitoring the physical (hot plate, and von Frey test) and chemical (formalin) responses to pain. Results: All ASN pharmacopuncture groups demonstrated significant differences in pain response to the hot plate test, von Frey test, and formalin test, compared to the control group (p < 0.05). The response of the ASN-M group and ASN-H groups to the hot plate, the formalin, and the von Frey tests were significantly different, compared to the lidocaine group (p < 0.05). Conclusion: ASN pharmacopuncture had a significant analgesic effect on SD rats in response to physical and chemical models of pain.

• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.232-238
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• 2019

Polyethylenimine-crosslinked chitin (PEI-chitin) was developed as a biosorbent to effectively remove dyestuffs from dye-containing wastewater. A representative reactive dye, Reactive Orange 16 (RO16) was used as a model dye. The effect of pH, isotherm, kinetic and desorption experiments were performed to evaluate the adsorption/desorption ability of PEI-chitin for RO16. As a result, the maximum adsorption capacity calculated by the Langmuir model was 266.3 mg/g at pH 2, and the time needed for adsorption equilibrium was evaluated to be about 20, 60, and 240 min for 50, 100, and 200 mg/L, respectively. The desorption experiments were carried out using various eluents such as ammonia/ethanol mixture, NaOH, $NaHCO_3$, and $Na_2CO_3$, and the highest desorption rate was 75.24% in the ammonia/ethanol mixture.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.306-312
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• 2008

This study investigated the influence of pH on the color development of melanoidins formed from amino acid enantiomer model systems. For this, the color development was evaluated by measuring browning at 420 nm and color measurements by spectrophotometry and colorimetry. The browning and browning index showed no difference according to the type of amino acid enantiomers, while that formed from the D-Asn system was the only difference according to pH level. The tristimulus value of melanoidins formed from all model systems was located on a dominant wavelength of 475 nm, the blue zone of the diagram. In addition, the $L^*$, $a^*$, $b^*$, $C^*_{ab}$ values, and ${\Delta}E^*$ index on the basis of the type of amino acid enantiomers, the differences were markedly found at pH 4.0. At pH 7.0, significantly differences were found in the $L^*$, $a^*$, $b^*$ values, and ${\Delta}E^*$ index and not in the case of the lysine enantiomers. In addition, at pH 10.0, the differences were found in the $a^*$ and $b^*$ values from the lysine enantiomers and $C^*_{ab}$ value from the asparagine enantiomers. Therefore, the color development of melanoidins was influenced by the type of amino acid enantiomers and pH levels. Especially, it is thought that the $a^*$ and $b^*$ values can be used to explain the differences among the amino acid enantiomers in the color development of melanoidins.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.39-48
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• 2009

Objectives : To clarify the possible effect of JS (Juglans sinensis), PCF (Psoralea corylifolia L.), and J+P(JS+PCF), we examined their influence on the development of pulmonary eosinophilic inflammation in the asthmatic murine model. Methods : All mice were immunized on two different days (21 days and 7 days before inhalational exposure) by intraperitonial injections of 0.2 ml alum-precipitated Ag containing 100 ${\mu}$g of OVA bound to 4 mg of aluminum hydroxide in PBS. Seven days after the second sensitization, mice were exposed to aerosolized ovalbumin for 30 minutes/day on 3 days/week for 8 weeks (at a flow rate of 250 L/min, 2.5% ovalbumin in normal saline) and, JS, PCF and J+P (200 mg/kg, 400 mg/kg) were orally administered 3 times per week for 8 weeks. Results : The suppressive effects of JS, PCF, and J+P were demonstrated by the accumulation of eosinophils into airways, with the reduction of eosinophils and lung leukocytes. These were correlated with the marked reduction of IL-4, IL-5, IL-13 levels in the BALF and serum. OVA-specific IgE levels were also decreased in serum and BAL from these mice. And also JS, PCF, and J+P decreased eosinophilic CCR3 and CD11b expression in lung tissue. Conclusions : These results indicate that JS, PCF, and J+P have deep inhibitory effects on airway inflammation and hyper-responsiveness in the asthmatic murine model. The suppression of IL-5, IgE, and eosinophilils and the increase of IFN-${\gamma}$ production in BALF seem to contribute to these effects. Specially, esosinophils and TNF-a in J+P combination group were significantly reduced in BALF and lung tissue. Hence, the results indicated that JS, PCF, and J+P could act as an immuno-modulator which possesses anti-inflammatory and anti-asthmatic property by modulating the imbalance between Th1 and Th2 cytokines.