• Journal of Korean Society on Water Environment
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• v.25 no.3
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• pp.386-393
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• 2009

This study was carried out to assess water quality and to introduce the management measures for water quality improvement with the collected data from 87 agricultural reservoirs in Han river watershed. According to the water quality criteria (WQC) for lake based on the COD, TP, TN and chl.a concentration, 18, 16, 4 and 19 of 87 reservoirs exceed class IV, respectively. Based on the trophic state index (TSI) with chl.a concentration, 51 of selected reservoirs appeared to be eutrophic. Phosphorus was limiting nutrient on algal growth in 58 reservoirs. TP, chl.a and COD concentration in 23 of 49 agricultural reservoirs with chl.a concentration ${\geq}25{\mu}g/L$ and eutrophic exceed class IV by WQC. Also, the mean depth in 21 of 23 reservoirs was below 5m. Our results suggest that advanced wastewater treatment and crop land control in watershed of reservoirs with TP concentration ${\geq}0.1mg/L$ would be a effective tool to improve water quality. Dredging would to be effective measure in reservoirs with mean depth < 5 m and relatively old age. In reservoirs with chl.a concentration ${\geq}50{\mu}g/L$, application of technique such dissolved air flotation (DAF) and P inactivation be effective to improve water quality by removing particulate matters in water column. The management measure to control inflow such as sedimentation basin, Pre-dam and diversion would to be application in reservoirs with shallow depth, while large watershed and surface area.

• Analytical Science and Technology
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• v.15 no.2
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• pp.157-162
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• 2002

A technique which could collect the traditional and the industrial hanji fibrous sludge efficiently from wastewater using a cationic surfactant cetyltrimethylammonium chloride (CTAC) was developed. When the concentration of CTAC was $1{\mu}g/mL$ in wastewater that the amount of the traditional hanji fibrous sludge was about 0.08 g/L, the collecting yield was more than 95% and the collecting time was less than 30 sec. When only CTAC was used to collect the industrial hanji fibrous sludge, about 90% of collecting yield was obtained at more than $15{\mu}g/mL$ CTAC. But the sludge layer at the surface of solution was not stabilized and the flotation time was relatively longer. And, when $5{\mu}g/mL$ CTAC and various amount of PAMID$^{(R)}$ was added to the industrial hanji sludge, the collecting yield was increased and sludge layer also was more stabilized. But the collecting yield was higher in the traditional hanji sludge than in the industrial hanji sludge.

• Korean Journal of Veterinary Service
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• v.36 no.3
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• pp.223-226
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• 2013

To evaluate the potential risk associated with zoonotic ascarid eggs in educational facilities and public playground in Seoul city, the sand samples collected from April to December in 2011 were examined with a fecal flotation method. Of 5,066 sand samples from 1,367 playgrounds tested, 12 sands from 12 places (0.88%) had ascarid eggs. Sand samples in educational facilities were more contaminated (10/870, 1.15%) with the parasite eggs than those of public playground area (2/497, 0.4%). Fisher's exact tests were used to make pairwise comparisons between which locations were more or less similar with regard to levels of contamination. We didn't find significantly different from one another. Most ascarid eggs detected were found in the Spring. Through this study, we hope to raise awareness of contamination of playgrounds by potentially infectious ascarid ova.

• Journal of Veterinary Clinics
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• v.37 no.2
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• pp.106-108
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• 2020

An eight-month-old, outdoor, intact male English Pointer dog weighing 23.5 kg presented to the hospital with signs of hematochezia, soft stools, and weight-loss. There were no remarkable findings on physical examination, complete blood count, serum biochemistry, electrolyte and gas analysis, and radiography. The serologic and Polymerase Chain Reaction (PCR) tests for canine parvovirus were negative. A fecal smear examination showed rod-shaped, sporeforming bacteria. Additionally, a fecal flotation test showed ova of Ancylostoma spp. The size of ova was 60 × 40 ㎛, and it was identified as Ancylostoma caninum using light microscopy. The PCR test indicated a Clostridial perfringens infection and the presence of C. perfringens alpha toxin. The diagnosis given was C. perfringens enterotoxicosis with ancylostomiasis. Treatment included antibiotics (metronidazole, trimethoprim-sulfamethoxazole) and anthelmintics (afoxolaner, milbemycin oxime). After two weeks, the clostridial infection resolved, but ancylostomiasis persisted for six weeks. The anthelmintic was changed to Drontal^â plus (praziquantel/pyrantel pamoate/febantel). After four weeks, there were no remarkable findings in the fecal samples, but the patient still presented with watery stools and hematochezia. Survey of abdominal ultrasound had performed, and a target-like sign with multiple rings was seen in the cecocolic region. The patient was diagnosed with A. caninum-induced cecocolic intussusception from the history and clinical signs. After a surgery, he recovered fully. This is the first clinical case report of Ancylostoma caninum parasitizing from the small intestine and causing an intussusception in the large intestine.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.4
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• pp.15-20
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• 2001

The function of the moisture-proof paper is to prevent moisture from adsorbing into the packed goods. Water-vapor transmission rate of the moisture-proof paper should be less than 100g/$m^2$.24hr and the optimum rate would be less than 50g/$m^2$.24hr. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. The purpose of this paper was to make moisture-proof paper using the mixture of SB latex and wax emulsion which was recyclable and environmentally friendly. Water vapor transmission rate showed less than 50g/$m^2$.24hr in mixture ratio of 85:15, 87:13, 90:10. Especially the mixture ratio of 87:13 showed the most favorable water-vapor transmission rate. However, the moisture-proof layer was destroyed slightly by folding in packing. It has been observed that there was no close relationship between water-vapor transmission rate of the moisture-proof paper and grammage of the base paper, but the density of base paper had influenced on water vapor transmission rate. It was also observed that the moisture-proof paper could be recycled. The moisture-proof paper was similar to base paper in degree of the pulping, and there was no significant difference in dispersion between moisture-proof paper and base paper. Most of wax particles which caused the spots during drying process could be removed by flotation process. Tensile strength and tear strength of both moisture-proof paper and base paper after pulping were measured to examine the fiber bonding, and no significant difference in physical properties was observed.

• Journal of Korea Water Resources Association
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• v.47 no.3
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• pp.247-256
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• 2014

A company, which is chicken butcherying-plant, was scheduled to increase up to twice output. We researched the way to increase up to twice the processing efficiency at the target biological treatment tank of A company. We performed for this study to obtain the reason why organic matter and nitrogen removal efficiency is increased when MLSS concentration is increased. It's performed at the target of pressure flotation water on SBR system. We performed the research which MLSS was 12,700 mg/L for 30hours (in aerobic condition for 25 hours and in anoxic condition for 5 hours). As a result, the nitrification was happened completely in aerobic condition within 25 hours. Denitrification efficiency was also over 90% when C/N ratio was over 3:1. After the experiment, we changed the concentration of MLSS 5,600 to 12,700 mg/L. In condition MLSS was about 11,000 mg/L and HRT were 30 hours meet the Effluent quality standard.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.604-610
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• 2018

Recently, due to the rapid growth of the leisure industry, demand for small-scale flotation and mooring pontoon platforms has been increasing rapidly. Standard rules for the design and structural safety of such structures have become necessary. This paper provides criteria that can be referenced when designing pontoon platforms, and also introduces structural safety evaluation procedures. In this study, the structural safety and stability of a 15-meter pontoon platform were investigated through structural design and finite element analysis. For platforms of less than 10 meters in length, a simple structural calculation can be used, but for platforms over 10 meters, a detailed structural strength review must be considered to meet safety guidelines defined in existing regulations. The structural strength of the initial design was examined and its structural safety was verified. For future research, it is an evaluative system was developed that can be used to examine the various loading conditions during design.

• Korean Journal of Veterinary Service
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• v.31 no.2
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• pp.207-217
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• 2008

This study was carried out to investigate the prevalence of fascioliasis of slaughtered and farmed cattle in Gwangju area from February to November in 2007. A total of 1,000 cattle fecal samples were collected from slaughter houses (n=805) and farms (n=185). Twelve (1.2%) were found as positive cases with excretion of the egg of Fasciola spp in the fecal specimens, and 128 (12.8%) were positive in intestinal parasitism using the flotation and sedimentation procedures. The infection rate of fluke larvae from the slaughtered cattle at abattoirs in Gwangju was 0.75% (6 out of 805 heads). In histopathology, there were several liver lesions such as inflammation with infiltration of eosinophil, polymorphonuclear cells, mononuclear cells and multinucleated giant cells, proliferation of connective tissue, calcification and abscess formation.

• Resources Recycling
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• v.24 no.4
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• pp.56-60
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• 2015

Fine particle classification was performed using products obtained from primary classification process after flotation for efficient application of tailing. The cut size increased with decreasing input pressure from 0.1 MPa to 0.3 MPa and increasing pulp density from 5% to 15% using 2-inch hydrocyclone. The median sizes of overflow and underflow were $6.56{\mu}m$ and $55.45{\mu}m$, respectively at 0.3 MPa with 5% pulp density. The imperfection became closed to ideal separation with increasing the pulp density and decreasing the input pressure. The water content decreased with increasing the pulp density, but the effect of input pressure could be ignored. The water content of underflow was 27.9% at 0.3 MPa with 15% pulp density.

• Journal of the Korean Society of Marine Environment & Safety
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• v.2 no.1
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• pp.57-65
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• 1996

The latest date, No. 1 YouII was grounded and sunk into the sea at MAMHYUNGJEDO ( South brother Island) in Sep. 21. 1995, and M.V. Sea Prince of V.L.C.C also made a big oil poullution accident owing to Typhoon "Paei" at front sea of Yeu Choun on Jul. 25. 1995. The large or small scall scale of oil poullution accident frequently was occurred about 300-350 cases per ine(1) year. The countries advanced in marine relations like as, nited Kingdom and Japan, have perfect system The country of expert education, training and oil recovery equipments in oil poullution accidents. The large quantity oil skimming ship's basic condition need general skimming ship which was high speed and large quantity skimming ability , and hve to store the recovered oil into tanks This oil skimming shop are composit the skimmer whuch move up and down according to the wace movements, storage tank which storage the recovered oil in after side, transfer pump which transformed from flooding tank to separating tank and separating tank which separated the oil mixtures, Also there are cylindrical floated which keep the auto positing, gate which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. Also there are cylindrical floated which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. The important arrangement is twin arm which moved by two hinge and move te skimming unit by wave movement. In gate of inside, made long wear in the gate bellow position, there are also connected the flexible hose for oil mixtures drop. The separating tank composited with multi-divided bulkhead for ffective oil and sea water separating by settling and flotation principle. As use the above natural princile and equipment, we can remove the large quantity oil by developed oil skimming ship.ming ship.