• Journal of Korean Society on Water Environment
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• v.28 no.4
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• pp.615-623
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• 2012

In this study, we evaluate the corrosion indexes (CI) such as Langelier Index (LI), Larson ratio (LR), Ryznar saturation index (RSI), Aggressiveness index (AI) of water quality for raw water, treated water and water in distribution reservoir at major eight drinking water treatment plants (DWTPs) in Korea. By analyzing secondary contamination of tap water, the variation of secondary contaminants was investigated with regard to pipe materials, aging and corrosion index (CI). In addition, we suggested an appropriate CI applicable water quality and the management plan for CI monitoriing. All CI showed corrosive water quality, and they did not change significantly in the distribution network. However, Copper (Cu), iron (Fe) and zinc (Zn) concentrations as secondary contaminants increased through the distribution network. Among CI, LI was most sensitive to changes in raw water quality and drinking water treatment. Also, it has high correlations with other indexes such as RSI, AI. Therefore, LI is considered as an appropriate CI to the domestic water quality. Based on these result, we propose LI as a drinking water quality standard to control the pipe corrosion from DWTPs.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.1 no.2
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• pp.49-60
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• 2003

The purpose of this study was to evaluate the effect of Halliwick 10 point program on the balance control. Fourteen undergraduate students participated in the experiment, and classified 7 experiment and 7 control group, randomly. Halliwick 10 point program was applied in the experiment group for 4 weeks. Balance index was measured using KAT 2000. Balance index were measured before, during(2 weeks), and after(4 weeks) the training for 4 weeks. 2-way repeated measures ANOVA was used to further distinguish between the groups. The following results were obtained; 1. The total balance index scores from a KAT were significantly decreased after 4 weeks compared with before the training passing of time. However there was no significant difference between experiment and control group. 2. The left and anterior shifting balance index scores from a KAT were significantly decreased after 4 weeks compared with before the training passing of time. However there was no significant difference between experiment and control group. These results lead us to the conclusion that the balance ability of women twenties increase as the water is higher than that of the ground applied Halliwick 10 point program of the water specific therapy province. Therefore, A further direction of this study will be to provide more evidence for Halliwick 10 point program in the water specific therapy.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.230-260
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• 1992

The paper was reviewed the research results on weed dynamics and effective control methods in direct-seeded rice crop. Direct seeding method resulted in drastic increment of weed growth compared to transplanting method and also changed in troublesome weed flora. Two to three fold more weeds were harvested at the direct seeded rice and weed flora of dominant species shifted toward $C_4$type grass weeds. Some of the important troublesome weeds in direct seeded rice were Echinochloa crus-galle, Oryza saliva ssp spontanea, Leptochloa chinensis. Setaria viridus. Digitaria adsendens, Sesbania exaltata, Aeschynomene indica, Algae, etc. Yield loss due to weed competiton was about 40-60% for water-seeded and about 70-100% for dry-seeded rice while these for transplanted rice were about 25-35% for mechanical transplanting and about 10-20% for manual transplanting, respectively. Integrated weed management concept was neede to approach weed control effectively. Several cultural technologies were very effective to suppress the weed growth. These were tillage operation, water management, seeding date and seeding rate. Crop residues of barley, rice, wheat, oat and italian ryegrass were also effectivly suppressed the paddy weeds particularly to Potamogeton distiuctus, a perennial broadleaf weed. A pathogen of Epicoccosorus nematosporus identified from Eleocharis kuroguwai was an excellent potential bioagent to control the most troublesome perennial sedge weed of E. Kuroguwai without arising any detrimental effect. The herbicidal efficacy of this pathogen was as high as bentazon herbicide. Plant growth regulator of paclobutrazol (pp-333) was another possible alternative to reduce the herbicide use. In current, herbicide exhibited the most conspicuous results to control weeds in direct-seeded rice even though the application technologies were not fully established. Recommendations for herbicide application were suggested for in both water-and dry-seeded rice in USA, Japan and Korea, respectively. To make better and comprehensive recommendations further studies on weed ecology and herbicide development were emphasized.

• Archives of Pharmacal Research
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• v.26 no.4
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• pp.321-329
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• 2003

Rats were given nicotine (25 ppm) in their drinking water at the start of their mating period in order to study the expressions of glutamate transporter subtypes in cerebellar astrocytes following the chronic exposure of nicotine after mating. After the offspring were delivered, each group was divided into two subgroups. One group, the control group, was given distilled water only and the other group, the experimental group, was given distilled water containing nicotine. The cerebellar astrocytes were prepared from 7 day-old pups at each group. Ten days after the cells were cultured, the expression of the glutamate transporter subtypes (GLAST and GLT-1) was determined using immunochemistry and immunoblotting. During the continuous treatments, the developmental expression patterns of the GLAST and GLT-1 in the cerebellum were also determined from 2, 4 and 8 week-old rats. The expression levels of GLAST in cultured astrocytes of both the pre- or post-natally exposed groups were higher than those of the control group. However, these expression levels of the continuously exposed group were lower than those of the control group. Compared to those of the control group, the GLT-1 expression levels of all the nicotine-treated groups were higher, particularly in the continuously treated group.. According to the results from the immochemistry procedure, the cerebellar GLAST and GLT-1 expression levels of all nicotine-treated groups were lower than those of the control group at each age. However, the immunoblotting procedure showed that the cerebellar GLT-1 expression levels of all the nicotine-treated groups were higher than those of the control group, except for the rats that were continuously exposed for 8 weeks using immunoblotting. These results suggest that the expression of the glial GLAST and GLT-1 are altered differently depending on the initial exposure time and the partcicular period of nicotine exposure. In addition, nicotine exposure during gestation has persistent effects on glial cells.

• The Journal of Advanced Prosthodontics
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• v.8 no.4
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• pp.290-295
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• 2016

PURPOSE. The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. MATERIALS AND METHODS. One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. RESULTS. Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. CONCLUSION. The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials.

• The Korea Journal of Herbology
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• v.23 no.1
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• pp.9-15
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• 2008

Objectives : This study was performed to investigate the effect of water extracts from Lagocephalus wheeled with several herbs(LW) on hyperlipemia and liver damage induced by alcohol. Methods : Except for the normal group, we fed rat on 25% alcohol for 55 days. And each extract was administrated for the same period. We measured the serum component in rat's blood, body weight and weight of liver. Results : At first, we observed effects of LW on hyperlipemia induced by alcohol. LW group didn't show significant increase of total cholesterol in comparison with those of the control group. LW group didn't show significant increase of HDL(High-Density lipoprotein) cholesterol in comparison with those of the control group. LW group showed significant decrease of triglyceride in comparison with those of the control group. LW group showed significant increase of body weight in comparison with those of the control group in 4weeks and 8weeks. LW group showed significant increase of liver weight in comparison with those of the control group. At second, we observed effects of LW on liver damage induced by alcohol. LW group showed significant decrease of ALP, GOT, GPT and LDH in comparison with those of the control group. Conclusions : Reviewing these experimental results, it appears that water extracts from Lagocephalus wheeleri with several herbs have pharmaceutical efficacy on hyperlipidemia and liver damage induced by alcohol. Therefore further additional study should be conducted to elucidate in depth the pharmaceutical efficacy of this.

• The Korea Journal of Herbology
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• v.26 no.3
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• pp.31-36
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• 2011

Objectives : This study was performed to investigate the effect of water extracts from Phyllostachys Folium(PF) on hyperlipiderma and liver damage induced by alcohol. Methods : Except for the normal group, we fed rat on 25% alcohol for 55 days. And extract was administrated for the same period. We measured the serum component in rat's blood, body weight and weight of liver. Results : At first, we observed effects of PF on hyperlipidemia induced by alcohol. PF group didn't show significant change of total cholesterol in comparison with those of the control group. PF group showed significant increase of HDL(High-Density lipoprotein) cholesterol in comparison with those of the control group. PF group showed significant decrease of triglyceride in comparison with those of the control group. PF group showed significant increase of body weight in comparison with those of the control group at 4weeks and 8weeks. At second, I observed effects of PF group on liver damage induced by alcohol. PF group showed significant decrease of GOT, GPT, ALP and LDH in comparison with those of the control group. PF group showed significant increase of liver weight in comparison with those of the control group. Conclusions : Reviewing these experimental results, it appears that water extracts from Phyllostachys Folium(PF) have pharmaceutical efficacy on hyperlipidemia and liver damage induced by alcohol. Therefore further additional study should be conducted to elucidate in depth the pharmaceutical efficacy of these.

• Journal of Environmental Science International
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• v.29 no.5
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• pp.559-573
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• 2020

The purpose of this study analyzed the overview of corrugated cardboasrd manufacturing industry and then provide direction for improvement. The BREF (BAT reference document) is an important reference for licensees and officer, including the best available techniques for the industry and achievable environmental performance, technical characteristics, and economic information. In the corrugated cardboard manufacturing process, wastewater pollutants are generated throughout the production process, and water is used in the dissociation and aging process. Atmospheric emissions are mostly generated by steam production from boilers and incinerators for the dry process. SO₂, NOx, CO₂, CO, HCl, dust, VOC, and odor were common. In the EU-BREF (European union BAT reference documents) BAT for wastewater have taken up a relatively large proportion. Items of water pollutants in wastewater were common in COD, BOD, N, P, SS, and however EU-BREF had different pollutants such as AOX and salt compared to K-BREF. In order to improve the quality of the K-BREF, it is necessary to devise basic data research method and data acqusitiom method. Consideration should be given to additional environmental management techniques that reflect the emissions characteristics of the corrugated cardboard manufacturing process. In addition, further research is needed to develop methodologies for selecting BATs considering environmental and economic feasibility.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.35-41
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• 2009

A waypoint tracking algorithm(WTA) is designed for Unmanned Surface Vehicle(USV) in which water-jet system is installed for propulsion To control the heading of USV for waypoint tracking, the steering nozzle of water-jet need, to be controlled. Firstly, target heading is calculated by using the position information of waypoints input from the land control center. Secondly, the command for the steering nozzle of water-jet is calculated in real time by using the heading and the rate-of-turn( ROT) from magnetic compass, In this study, in order to consider the drift angle due to external disturbance such as wind and wave, the course of ground( COG) can be used instead of heading at higher speed than a certain value, To test the performance of newly-designed WTA, the tests were carried out in actual sea area near Gwang-an bridge of Busan. In this paper, the sea trial test results from WTA are analyzed and compared with those from manual control and those from commercial controller.

• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.28-34
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• 1997

This study was carried out to investigate the effects of prechlorination and algae growth on THMs generation. The sample water obtained from Paldang Dam which is a main source of raw water for the Seoul metropolitan area. THMs concentration in the sample water was investigated in water treatment process prechlorifiation, chemical coagulation, and sand filtration. And also, THMs concentration were analyzed in the water which cultured algae in laboratory. The results were as follows 1. The THMs concentration produced by prechlorination unit process were increased in control (not purified) but decreased in process of purification. 2. The THMs concertration can reduce by increasing the number of cleaning filters. 3. The main precursor in raw water for the THMs generation was supplied by algae growth. So as to reduce the THMs concentration in water supplying system, it is the best method to manage algae growth in water body of Paldang reservoir.