• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.475-484
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• 2000

The purpose of this study was to develop model for estimating biodegrability of organic sludge (sewage and papermill) in various environmental conditions. to assume degradable degree with operating time of SRB reactor. and evaluate duratior of organic sludge as carbon source. Average TCOD was 28.7~63.2mg/L in effluent. organic sludge did not much supply carbon source for experimental period. But in point of durability. it seemed that organic sludge was efficient because it was not consumed by degradation of much organic matter within short period. With increasing $SO_4{^{2-}}$ reduction rate. Pb and Fe was removed 77~82% and 33~59%. respectively. Because Al was precipitated as a hydroxide. its removal rate wa,. about $54{\pm}2%$ in R-l~R-3 maintaining low pH but about 78% in R-4 maintaining high pH. Because Mn was large in solubility. it showed to be much lower than other heavy metals. Considering supportable capacity or durability of orgainc matter for initial SRB mixing ratio of sewage/papermill 0.5 was regarded as appropriate substituting material and at this time. it estimated that carbon source continued about 3.08 year but safety factor must apply to be thought over. because various factors had an effect on degradation of organic sludge.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.3
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• pp.463-473
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• 2000

This research was carried out to investigate chemical pretreatment using limestone in treating abandoned metallic mine drainage with anaerobic biological treatment, and to estimate application of papermill and livestock sludge as carbon sources for SRB (Sulfate Reducing Bacterial. Capacity of anaerobic limestone bed was steeply decreased. But if limestone was utilized as pretreatment process in treating them with anaerobic biological treatment. it could look forward to stabilize system because it did initally neutralize them. Effluent SCOD in R-4 was lower than R-l~R-3 in inital HRT 5day but its concentration was high in HRT 1day after passed time. Therefore in point of durability and supply of organic matter. it seemed that R-4 was useful became organic matter in R-4 was not consumed by excessive degradation within short period. In all reactors, pH was suitable for SRB growth in whole HRT, but on the evidence of ORP, SRB was active after HRT 2day. Fixation trend of heavy meta s showed high as $SO_4{^{2-}}$ reduction efficiency increased, and $SO_4{^{2-}}$ reduction and fixation of heavy metals were relatively high in HET 2day.

• The Korean Journal of Pharmacology
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• v.24 no.1
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• pp.125-134
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• 1988

A single i.v. dose of streptozotocin (65 mg/kg) given to rats has produced a marked hyper-glycemia (>500 mg serum glucose/dl). Since the Atractylodis Rhizoma is known to have hypo-glycemic action, the water extracts of Atractylodis Rhizoma (ARWE) was given to the streptozotocin-induced (SZ) hyperglycemic rats. To determine whether ARWE has the anti-hyperglycemic effects, two different daily doses of ARWE (i.e.0.2 g/kg and 2.0 g/kg) were given orally to the SZ rats for up to 8 days. Thereupon, serum levels of glucose, insulin, amylase and cholesterol were determined on days 1, 3 and 8, following the initial and repeated daily administrations of ARWE. On day 8, glycogen content and glucose-6-phosphatase activity in the liver were assayed. Results showed that ARWE decreased the serum glucose levels, which had been markedly elevated by the SZ pre-treatment. In support of this, the serum insulin level, which had been quickly lowered by the SZ pre-treatment $(20{\mu}U/ml)$, was quickly elevated in the ARWE dose dependent manner that, at 2.0 g/kg ARWE, the serum insulin level was increased $(20{\mu}U/ml)$ above the normal level $(42{\mu}U/ml)$. Also, the serum amylase level, which was steadily decreasing after the SZ pre-treatment, was restored to the normal level folowing 8 day of ARWE (2.0 g/kg) treatment. Hepatic glycogen content and glucose-6-phosphatase activity, which decreased and increased, respectively in the 52 treatment group, were restored toward the normal level in SZ plus ARWE group.

• The Journal of the Korea Contents Association
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• v.8 no.1
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• pp.59-67
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• 2008

Stalking is defined as an abnormal or long term pattern of threat of harassment directed toward a specific individual and obsessional following. This study use empirical method based on the self administrated questionnaire of 325 male and female university students in Korea, for understanding the actual conditions of stalking. The findings are as follows. First, 18(5.5%) students experienced the victimization of stalking. Female students were more likely to be victims of stalking than male. 4(1.3%) of students were stalkers. Second, Female students were more likely to be stalkers than male. The age of most stalkers were younger than 27 yrs.. And most stalking victims knew their stalker. Third, the most cause of stalking was revenge for denial of courtship. The most methods of stalking were making approaches and the communications via letter, telephone, and giving presents. And the most period of Stalking was in 6 months.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.293-301
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• 2005

We conducted several different leaching experiments for assessing the potential environmental risk when utilizing recycled concrete for stabilizing bridge pier. The methods include continuous batch leaching test (DIN 38414-S4), availability test (NEN 7341), pH-stat test (CEN/TC 292/WG6) and tank diffusion test (NEN 7345). The concentration ranges vary depending on the testing method. Nearly all the trace elements were low, some elements recording under detection limit. The maximum concentrations for trace elements leached throughout the whole tests are (as mg/L); Cd (0.029), Cu (0.437), Pb (0.14), Ni, Zn (0.95), Hg (0.005). Although the testing methods we used in this study are much more rigorous than other commonly adapted method including TCLP and domestic testing method for solid waste, the trace elemental concentrations are under the criteria for hazardous material set by the TCLP and domestic method. The result seems to suggest that applying the recycled concrete on stream water will be accepatable practice as for as trace elements are concerned. However, the influence of inorganics such as Ca, Mg, Ni and $SO_4^{2-}$ on aquatic ecology should be further examined.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.9
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• pp.542-547
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• 2017

This paper was to analyze the membrane characterization of hydrophilicity, surface morphology and membrane chemical anlysis of three commercial microfiltration/ultrafiltration membranes, and evaluate the filtration performance of a seawater to assess the availability for pretreatment of desalination process. From the results of contact angle, Mem-3, fabricated with polyacrylonitrile, was highly hydrophilic. It find out that Mem-3 has more anti-biofouling property. In Field emission scanning electron microscope (FESEM), Mem-1 (polyethylene) and Mem-2 (Polyvinylidenefluoride) showed the sponge-like shape and Mem-3 showed finger-like shape. Membrane chemical analysis by energy dispersive spectrometer (EDS) presented that Mem-2 was mostly fluoride and Mem-3 had s high ratio of N (32.47%) due to the nitrile group. The permeation flowrate per time on suction pressures using deionized water (D.I. water) tends that permeation rate of Mem-3 more increased when the pressure was increased compared to other membranes. From the results of turbidity and total suspended solids (TSS) removal, turbidity of permeate was 0.191 NTU to 0.406 NTU and TSS was 2.2 mg/L to 3.0 mg/L in all membranes, indicating that it was not suitable for the pretreatment of seawater desalination by short-term experiments.

• Journal of Nutrition and Health
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• v.24 no.4
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• pp.326-336
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• 1991

Present study was to investigate the effect of dietary vegetable sources such as carrot, peahull and squash on mineral balance of Na, K, Ca, Fe, Cu, Zn and Mg in mice. It would also determine if the kind, level and feeding period of vegetables can affect the mineral balance. One hundred and thirty mice weighing $29{\sim}30g$(8 weeks of age) were randomly selected. Ten mice were fed their standard diet, and the others were divided into three experimental groups that were fed standard diet supplemented with carrot, peahull and squash. Mineral intake and urinary and fecal excretion of minerals were measured to investigate the effect of the kind, level and feeding period of vegetables on absorption rate and balance of minerals. Body-weight gain was increased in high peahull diet group compared to the control. No significant difference was observed for feed efficiency ratios between different experimental groups and urine volume was increased by vegetable fed group. Na, Ca, Fe, and Cu intake were lower in high squash-diet fed soup. K intake was higher in carrot fed mice, and Zn, and Mg intake were higher in peahull fed mice. Absorption rate and balance of mineral in control group resulted in positive balance while experimental groups showed negative. The kind of vegetable, feeding level and feeding period affected the intake of Na, K, Ca, Cu and absorption rate of Cu, Zn and balance of K, Cu, Zn to negative. In spite of the higher intake of t Zn and Mg, in experimental groups the absorption rate showed negative balance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.552-562
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• 2016

Although a number of studies have been conducted in Korea since 2000 on the impact of early English education, their interpretation is still not conclusive, due to their lack of control groups and failure to control for third factors and use valid measurements. The present study was designed to examine the effect of an English education program on young children's English proficiency after 8 months using the most well-known official English proficiency measure, the WIDA for kindergarteners. In addition, the children's Korean language proficiency, cognitive abilities, personality, parents' SES, and parents' attitudinal variables before the education were measured and controlled. The results indicated that the intervention group performed better than the control group in both listening and speaking skills, even when all relevant factors were considered. This effect, however, was only found in the item-level analyses.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.7
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• pp.297-306
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• 2017

Citizens want more accurate forecast information using Bus Information System. However, most bus information systems that use an average based short-term prediction algorithm include many errors because they do not consider the effects of the traffic flow, signal period, and halting time. In this paper, we try to improve the precision of forecast information by analyzing the influencing factors of the error, thereby making the convenience of the citizens. We analyzed the influence factors of the error using BIS data. It is shown in the analyzed data that the effects of the time characteristics and geographical conditions are mixed, and that effects on halting time and passes speed is different. Therefore, the halt time is constructed using Generalized Additive Model with explanatory variable such as hour, GPS coordinate and number of routes, and we used Hidden Markov Model to construct a pattern considering the influence of traffic flow on the unit section. As a result of the pattern construction, accurate real-time forecasting and long-term prediction of route travel time were possible. Finally, it is shown that this model is suitable for travel time prediction through statistical test between observed data and predicted data. As a result of this paper, we can provide more precise forecast information to the citizens, and we think that long-term forecasting can play an important role in decision making such as route scheduling.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.335-351
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• 1992

The identification of green algae which were collected from paddy rice fields of the whole nation was conducted in 1991, and also the reproduction processes of three important green algae were investigated. The green algae identified were 46 species in 16 families including 4 species in the Volvocaceae, 4 species in the Palmellaceae, 3 species in the Ulotrichaceae, 3 species in the Oocystaceae and 6 species in the Scenedesmaceae. It was recognized that the algae which have caused a large injury to the flooded direct-seeded rice in Seosan reclaimed saline land was the genus Cladophora. The green water blooms on paddy water were induced mostly by the concentrated populations of suspended green algae such as the genera, Chlamydomonas and Stichococcus. A rapid propagation of Hydrodictyon was resulted from the asexual reproduction forming autocolony in each mother cell. The sexual and asexual reproduction processes of Oedogonium and the sexual reproduction process of Spirogyra were observed.