• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.86-87
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• 2003

본 실험은 전복 종묘생산 시 먹이생물로 적합한 부착 규조를 파악하기 위하여 실시하였다. 부경대학교 한국해양 미세 조류 은행에서 보유한 부착 규조종 중, 해역, 크기, 부착력, 영양분석 결과를 고려하여, 11종의 부착 규조를 선택하였다. 각 부착 규조를 f/2 배지로 파판에 배양 한 후 평균 각장 7mm의 까막전복 치패를 대상으로 26일 간 먹이 효율을 조사하였다. 또 이 실험의 결과를 토대로 먹이 효율이 좋은 4종의 부착 규조를 선택하여 참전복 유생의 부착율과 먹이 효율을 조사하였다. 참전복 유생은 수정 후 56 시간이 지난 veliger유생을 이용하여 각 규조에 따른 유생의 부착율, 사망률, 변태율, 성장률을 측정하였다. 까막전복 치패를 대상으로 규조종별 먹이 효율을 실험한 결과, 생존율은 Caloneis schroder가 37.1%, Nitzchia sp. 35.0%, Navicula sp.가 31.4%로 대체로 높은 생존율을 보인 반면에, Navicula elegans이 6.4%, Cylidrotheca closterium.은 11.7%로 낮은 생존율을 보였다. 실험 종료후, 까막전복 각장의 성장을 측정한 결과, Cocconeis californica가 9.33 mm, Achnanthes sp.은 9.27 mm으로 대체로 높은 성장을 보였다. 이에 반해 Navicula elegans은 8.60 mm으로 낮은 성장을 보였다. 전복 전중과 육중은 Amphora sp.에서 각각 87.7mg, 35.2mg 으로 가장 높았으며, Cocconeis californica와 Achnanthes sp.에서도 대체적으로 높게 나타났다. Navicula elegans는 각장의 성장에서와 같이 가장 낮은 증육을 보였다. 규조 4종을 대상으로 한 참전복 유생의 부착율 에서는 수정 후 152시간 후 Cocconies califonica에서 47.3%로 가장 높은 반면, Caloneis schroder 에서 23.8%로 가장 낮았다. 실험 9일째 사망률은 Cocconeis californica에서 63.6%로 가장 낮게 나타났고, Nitzchia sp.에서 90.4%로 가장 높게 나타났다. 유생의 변태율은 Cocconeis californica에서 98.5%로 가장 높은 결과를 보였다. 유생의 일간 성장율 역시 Cocconeis californica에서 25.4 $\mu\textrm{m}$/day로 높았고, Nitzchia sp.에서 13.9 $\mu\textrm{m}$/day로 낮았다. 실험 24일째 참전복 유생의 최종 생존율은 변태율과 일간 성장률이 높았던, Cocconeis californica에서 7.8%로 가장 높게 나타났다.

• The tire
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• s.243
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• pp.26-29
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• 2010

앞으로 승용차용 타이어에도 전기냉장고나 세탁기 등에 부착되는 '에너지효율 등급표시'가 부착될 예정이다. 정부(지식경제부)는 지난 4월 5일 승용차 운행단계에서의 에너지소비효율(연비) 개선을 위하여 2011년 하반기부터 "타이어 효율등급제도"의 도입 계획을 발표하였다. 우리협회(대한타이어공업협회)는 동 제도의 원활한 도입과 효율적인 운영 및 정착을 위하여 적극 지원할 예정이다.

• Korean Journal of Plant Resources
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• v.15 no.1
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• pp.72-76
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• 2002

This study was carried out to determine an effective mechanical harvester for rhizomes of Rehmannia glutinosa Libosch. Labor-saving efficiency showed 69∼76% by using tillage operations with power tiller, digger attached to power tiller, and digger attached to tractor compared with manual harvest. Loss percentage of rhizomes by mechanical harvesters was 3.1∼ 9.3% higher, and fresh rhizome yield was 2∼6％ lower than that by manual harvest, respectively. Although it showed higher loss percentage of rhizomes and lower fresh rhizome yield compared with manual harvest, mechanical harvest using digger attached to power tiller or digger attached to tractor was effective in labor-saving for rhizomes of Rehmannia glutinosa Libosch.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.4
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• pp.239-248
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• 2017

It is important to understand the dispersion and deposition characteristics of particles in the flow around a circular cylinder. The rotation of a cylinder is considered as a means to modify the particle deposition in this study. We numerically investigate the effects of the rotational speed of a cylinder and the particle Stokes number on particle dispersion and deposition as well as flow characteristics. Results show that the deposition efficiency of small particles (with the Stokes number smaller than 4) decreases significantly as the rotational speed increases. However, when the Stokes number is larger than 4, the deposition efficiency increases slightly with the rotational speed of the cylinder. Meanwhile, for a given rotational speed, the increase in the Stokes number leads to an increase in deposition efficiency and deposited area.

• Journal of Marine Life Science
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• v.9 no.1
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• pp.22-32
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• 2024

The purpose of this study was to determine the effect of external biologger attachment methods on the blood parameters and attachment efficiency of spotted sea bass Lateolabrax maculatus (mean body weight 2630.8 g). The fish were tagged using four different external attachment methods with dummy biologgers: no attachment (control), anchor attachment (AA), monofilament attachment (MA), and silicon tube attachment (SA), each with triplicates. Blood indices and biologger attachment efficiency were assessed on days 1, 7, 14, 28, 56, and 84 after attachment. The concentrations of hematocrit, Na⁺, Cl^-, glutamic pyruvic transaminase and total protein, and the activity of superoxide dismutase in blood were not affected by the external attachment method of biologger. The concentrations of glutamic oxaloacetic transaminase (day 1 of attachment), hemoglobin (day 56) and total cholesterol (day 56 and 84) in AA group, the concentrations of glucose and cortisol (day 14) and total cholesterol (day 84) in MA group showed significantly higher than those of control (p<0.05). During the experiment period, the SA group had no differences from the control in all blood properties. The biologger attachment efficiencies of the AA, MA, and SA groups after 84 days were 0.0%, 33.3%, and 100.0%, respectively. These results indicate that the optimum external biologger attachment method under our experimental conditions is SA type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.157-160
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• 2002

This study was carried out to the harvesting efficiency of equipment used fer harvesting of rhizomes of Saururus chinensis Bail. Labor-saving efficiency showed 60-67% enhancement by using tillage operations with power tiller, digger attached to power tiller, and digger attached to tractor compared with manual harvest. Loss percentage of rhizomes by harvesting equipments was 2.2-8.8% lower than by manual harvest. Fresh rhizome yield and income index were increased 3-10% and 13-27% respectively by harvesting equipments, showing the highest yield and index in digger attached to tractor, Thus, digger attached to tractor showed the most effective harvest equipment for Saururus chinensis rhizome.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.241-248
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• 1986

New Paint, Stapol N-6200D, products from Song Woun Industrial Co. Ltd., was tested on its chemical effect on fouling organisms attached to fishing nets. Two kinds of fishing nets with different mesh size, 5 mm (cage culture net) and 33 mm (set net) were painted and attached to $1m^2$ PVC quadrates. The quadrates with painted or non-painted fishing nets were placed at the surface water layer of southern coast of Korea. Monthly species composition and abundance of fouling organisms were analysed as well as total weight of fouling organisms including mud on fishing nets. On the other hand, anti-fouling effect of the organisms and mud on different color paints was studied and the durability of chemical effect of painted fishing net on fouling organisms was also estimated.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.1
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• pp.123-128
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• 2016

The effect of propeller surface roughness condition on ship performance is very significant even the influence of fouling on propeller performance is not well established compared to biofouling on the hull surface. In present study, predictions of open water efficiency of propeller are made for three different fouling conditions, and its application is given for the 7m full-scale propeller of a medium-size tanker in open water condition. The numerical predictions of propeller efficiency loss due to fouling are based on the results from laboratory-scale drag measurements and boundary layer similarity law analysis presented in Schultz (2007) together with an in-house unsteady lifting surface code which is an appropriate tool to predict the effect of propeller surface roughness on propeller performance. The results of this study indicate that the subject propeller with the small calcareous fouling ($k_s=0.001$) can lead to as high as 15 % loss at the propeller operating condition (J=0.5) and the loss of propeller efficiency due to fouling should be evaluated while the ship is operating.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1999.04a
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• pp.94-96
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• 1999

충북 단양에 위치한 조일 광산에서 채취한 구리와 아연으로 오염된 광미(광산 폐기물로서 금속 추출 후 남은 찌꺼기)를 효율적으로 처리하기 위한 생물학적 용출기법(bioleaching) 에서 기본 배지 조성(9K medium)을 변화시켜 미생물의 표면 특성을 측정하고 미생물 표면 특성이 용출 효율에 미치는 영향을 관찰하였다. 인을 첨가하지 않았을 때 소수성 값은 62.5％, 질소원 농도가 45mM일 때의 소수성 값은 66.7%로 미생물 표면 특성이 가장 소수성인 특성을 가지고 있었으며, 구리와 아연의 용출 효율도 가장 높게 나타나는 상관 관계를 나타냈다. 또한 광미에 부착된 미생물의 양을 측정해 본 결과, 미생물 표면 특성이 소수성일수록 광미에 부착된 미생물의 양도 많다는 것을 알 수 있었다.

• Product Safety
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• s.211
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• pp.15-15
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• 2011

지식경제부는 자동차 운행단계에서의 에너지효율(연비) 개선을 위해 2011년 11월부터 "타이어 효율등급제도"를 시행할 계획이라고 발표했다.