• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.181-182
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• 2012

This study aims to present about structural marina floats to yacht enhancement. Yacht marina facilities take long time and huge budget. The current ministry of land, transport and maritime affairs is planning to select an optimal design and spot for marina float base to yacht enhancement using Mokpo harbor. First, this paper focuses on marine floatation system to find requirements of selection. Second it points out sample structural marina floats in practice. Finally, this paper presents some recommendations for developing plan and method.

• Korean Journal of Veterinary Service
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• v.16 no.1
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• pp.82-89
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• 1993

In order to detection of the intestinal parasites, fecal samples were taken from broiler (n=262), laying hen(n=244), parent stock(n=207) and native stock(n=287) in Chonbuk province. The prevalence and identification of intestinal parasites were determined by the fecal examination using the floatation and /or sedimentation methods and microscopical examination, respectively. The results were obtained as follows : 1. The detection rate of parasite-eggs from 4 flocks(total=1,000) was 65.7%. 2. In the breed and type of breeding, infection rate of parasite-eggs was detected 84.0％ as native stock (floor breeding, 241 chicken), 79.7％ as parent stock (floor breeding, 165 chickens), 73.3% as broiler(floor breeding, 192 chicken) and 24.2% as laying hen(cage breeding, 59 chicken), in order. 3. In the concern of mixed infection such as single, double and triple, the rate was 55.1%, 8.7% and 1.9%, respectively. 4. Ten kinds of infective eggs were isolated from 657 fecal sample of 4 flock. They were classified 51.l% as Eimeria spp., 12.7% as Ascaridia galli, 5.1% as Capillaria spp., 4.1% as Strongyloides avium, 2.3% as Heterakis gallinarum, 0.5% as Hymenolepis spp., 0.3% as Railleina spp. and 0.2% as Syngamus spp., Trichostrongilus spp., or Choanoteania spp., single or in combination.

• Parasites, Hosts and Diseases
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• v.59 no.2
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• pp.153-157
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• 2021

This study reports the first two clinical cases of spirometrosis caused by Spirometra sp. in cats in Korea. In these two cases, the cats vomited, and long proglottids of tapeworm were recovered. The sick cats presented with anorexia and lethargy. However, they unexpectedly showed no diarrhea, which is the main symptom of spirometrosis. Based on a fecal floatation test as well as morphological and molecular analyses, the parasite was diagnosed as Spirometra sp. The 2 cases were treated with praziquantel. This study suggests regular monitoring of health and deworming in companion animals, even when animals are well cared for, with regular preventive medication. Additionally, spirometrosis should be considered in the differential diagnosis in cases of gastrointestinal symptoms in Spirometra endemic areas.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.474-474
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• 2022

미세플라스틱이 물 환경으로 배출되는 주요 경로로는 하수처리장 방류수와 강우유출수가 있다. 하수처리장 및 유역에서 배출된 미세플라스틱은 하천과 하구역을 거쳐 해양과 같은 대규모 수역으로 이동하는데, 이 과정에서 해양뿐만 아니라 담수호, 저수지 등과 같은 공공수역에도 미세플라스틱이 지속적으로 축적되고 있다. 특히 강우유출수에 포함된 미세플라스틱은 적절한 처리 과정 없이 하천으로 유입되는 경우가 많아 공공수역 내 미세플라스틱 저감 기술의 필요성이 증가하고 있다. 그러나 미세플라스틱 관련 기존 연구는 미세플라스틱의 분포 등 현황에 대한 모니터링 및 환경위해성과 관련한 것이 대부분이며, 미세플라스틱 저감기술 관련 연구 또한 일부 정수처리 및 하수처리 공정을 대상으로 하는 초기 단계의 연구가 진행되고 있을 뿐 공공수역에서의 미세플라스틱 저감기술 개발 관련 연구는 전무한 실정이다. 따라서, 본 연구에서는 기존의 물리·화학적 수처리 공정인 용존공기부상법(Dissolved Air Flotation, DAF)에 물의 전기분해 시발생하는 브라운가스를 활용하여 응집된 물질을 빠르게 부상시켜 수체 내 오염물질을 제거할 수 있는 기술을 통해 수체 내 미세플라스틱 저감효과를 분석하였다. 또한, 해당 기술을 공공수역인 저수지에 적용하여 오염물질과 함께 미세플라스틱을 제거할 수 있는지 검토하였다.

• Environmental Engineering Research
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• v.23 no.1
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• pp.36-45
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• 2018

The phosphogypsum (PG) is a byproduct of the phosphate fertilizers manufacture. The world production estimated to 200 million tons per year induces environmental threats and storage problems, which requires strict policies to limit pollution and encourage its valorization. This paper presents a purification process of the crude PG including treatment with a diluted sulfuric acid, floatation, filtration and washing. The purified PG is used to produce plaster. The process optimization was conducted using a full factorial design. The significant factors considered in the experimental study are temperature ($X_1$), volume of sulfuric acid solution ($X_2$) and PG quantity ($X_3$). The main effects and interaction effects of these factors on the responses of the % $P_2O_5$, % F, Total Organic Carbon (TOC) ($mg{\cdot}kg^{-1}$) and pH were analyzed. The optimum conditions for $X_1$, $X_2$ and $X_3$ were found to be $60^{\circ}C$, 3 L and 1 kg, respectively and the optimized pH values was found to be 6.2. Under these conditions, 60% of $P_2O_5$, 95% of Fluorine and 98% of TOC were removed from PG. The predicted values were found approximately the same as the experimental ones. The plaster produced with purified PG was found to have similar properties to that produced from natural gypsum.

• Journal of Environmental Health Sciences
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• v.9 no.2
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• pp.11-17
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• 1983

The soil-transmitted helminthes, such as ascaris, whipworm, hookworm and trichostrongylus, have been considered as the most prevalent parasitic diseases in a matter of several decades ago in Korea. In facts, the attached eggs and/or larvae to the vegetables have been played a great role on the transmission to human because of raw eating the vegetables without the proper recipe. The aims of this study is to outline the attached helminthes egg in vegetables and to define whether the detection rates on them show a decreasing pattern or not in present. The subjected vegetables were collected from the three markets which are located at Goo-Pa Bal, Soo-Yoo Dong, Cheon-Ho Dong in suburban area, Seoul from April to May 1983. A total of 180 samples including such as 60 Korean cabbages, 60 young radishes and 60 Korean onions were examined. For the detection of helminthes eggs, the both methods of formalin-ether sedimentation and zinc-sulfate floatation were applied. The results were summarized as follows: 1) The detected eggs of ascaris, whipworm, hookworm, trichostrongylus and either filariform larvae or rhabditoidform larvae of hookworm, as well as unknown ones were found in vegetables subjected. 2) Out of 180 subjects, the overall detection rate showed 48 (26.7%). And in case of Korean onion, the rate revealed 22 heads (36.7%) among 60, 17 heads (28.3%) out of 60 Korean cabbages, 9 roots (15.0%) out of 60 young radishes respectively. 3) The ascaris eggs were detected 6 heads (10%) out of 60 Korean cabbages, while the filariform larvae of hookworm appeared in 7 heads (11.7%) among 60 Korean onions. 4) In the results of present study, the detection rates in vegetables were appeared to be the marked decreasing tendency as like 28.3%, 36.7%, 15% compared with 96%, 100%, 88% of previous investigators (Choi et al. 1967)each on Korean cabbage, Korean onion, young radish.

• Clean Technology
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• v.10 no.4
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• pp.195-201
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• 2004

Cellulase was modified with copolymer with polyethylene(PE)/polypropylene(PP) oxide and maleic anhydride(MA) by maleylation reaction, and modified cellulase was applied to the reprocessing of old newsprint (ONP). Cellulase of modified cellulase enhanced the detachment of ink particles by fibrillation of fiber. The copolymer, which acted as the surfactant formed bubbles and removed the ink particles in the floatation process. Modified cellulase showed the same deinking ability without excess dosage compared with the conventional method. And, it improved the physical properties including tensile strength, brightness, and whiteness compared with the conventional deinking process. The bond between the ink and fiber got stronger as the storage time increased, and it became very difficult to remove the ink particle. But, modified cellulase increased the deinking ability by 41% compared with the conventional process at the experiment of the ONP for 1 year storage time. It removed the yellowing and increased the whiteness and brightness as well as tensile strength and internal bond strength.

• Korean Journal of Plant Tissue Culture
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• v.24 no.4
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• pp.197-201
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• 1997

Plant seed oil-bodies or oleosomes ate the repository of the neutral lipid stored in seeds. These organelles in many oilseeds may comprise half of the total cellular volume. Oleosomes are surrounded by a half-unit membrane of phospholipid into which are embedded proteins called oleosins. Oleosins are present at high density on the oil-body surface and after storage proteins comprise the most abundant proteins in oilseeds. Oleosins are specifically targeted and anchored to oil-bodies after co-translation on the ER. It has been shown that the amino-acid sequences responsible for this unique targeting reside primarily in the central hydrophobic tore of the oleosin polypeptide. In addition, a signal-like sequence is found near the junction of the hydrophobic domain and ann N-terminal hydrophilic / amphipathic domain. This "signal" which is uncleaved is also essential for correct targeting. Oil-bodies and their associated oleosins may be recovered by floatation centrifugation of aqueous seed extracts. This simple partitioning step results in a dramatic enrichment for oleosins in the oil-body fraction. In the light of these properties, we reasoned that it would be feasible to create fusion proteins on oil-bodies comprising oleosins and an additional valuable protein of pharmaceutical or industrial interest. It was further postulated that if these proteins were displayed on the outer surface of oil-bodies, it would be possible to release them from the purified oil-bodies using chemical or proteolytic cleavage. This could result in a simple means of recovering high-value protein from seeds at a significant (i.e. commercial) scale. This procedure has been successfully reduced to practice for a wide variety of proteins of therapeutic, industrial and food no. The utillity of the method will be discussed using a blood anticoagulant, hirudin, and industrial enzymes as key examples.

• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.501-507
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• 1991

Diagnosis of cryptosporidiosis is currently confirmed by the detection of the oocysts or endogenous stages in fecal or tissue samples. Various conventional staining methods and serodiagnostic techniques have been reported, but the latter has far been limited to a few laboratories. Cryptosporidium has recently been reported in mice and chiekens in Korea, but there has been no report on staining methods to the oocysts. The present study was performed by light and scanning electron microscopic observations, and discussed with staining properties of four conventional methods such as dichromate solution floatation method, Carbol fuchsin stain, Auramine-O stain and Giemsa stain method. Cryptosporidial oocysts were isolated from the laboratory mouse. In tissue sections of duodenum, jejunum, ileum, cecum and upper colon, numerous very small, basophilic bodies were observed on the border of mucosal epithelial cells. In scanning electron microscopic observations, a few of developmental stages of Cryptosporidium were seen. Two types of thick and thin-walled oocysts were recognized in the intestinal contents. Mean size of its were $5.19{\pm}0.23{\times}4.31{\pm}0.32{\mu}m$ and $5.14{\pm}0.25{\times}4.27{\pm}0.4{\mu}m$, respectively. Carbol fuchsin and Auramine-O stain methods are recommended as the satisfactory ones for the identification of Cryptosporidium oocysts. Giemsa stain was also recommended as available in the laboratory, because a few of developmental stage fo Cryptosporidium could be seen by it.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.37 no.2
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• pp.140-146
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• 2001

In order to analyze the photodegradation of plastic materials for floats or frames of fisheries facilities, weathering experiment on 3 kinds of plastic materials like high density PE of Korea(KHDPE) and Norway(NHDPE) and high strength PVC(Hi-PVC) was carried out during 900 hours exposure by using xenon light source of weather-Ometer. The results obtained are as follows; With increasing of ultraviolet radiation(UVR) time, a remarkable losses in the mechanical properties of each specimen were observed except for the remaining strain of HDPE materials. As NHDPE lost almost 15% of its initial tensile stress during a 900 hours exposure followed by KHDPE 12% and Hi-PVC 6%. In addition, the remaining tensile stress RS(kg/$mm^2$) decreases almost linearly with the lapse of exposure time to light Y(Year) and the empirical equations of each specimen computed as follows; KHDPE : RS=2.6769-0.0003Y($r^2$=0.63) Hi-PVC : RS=5.3470-0.0003Y($r^2$=0.91) NHDPE : RS=2.4929-0.0004Y($r^2$=0.97) It was observed by scanning electron microscope that all specimens with UVR time had started to decompose and had bubbled areas and small holes.