• 한국농공학회논문집
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• 제53권2호
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• pp.75-82
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• 2011

This study was performed to evaluate the water purification properties of bio-composites planting blocks using oyster shell and effective microorganism that have high absorption ability of heavy metals and organics to develop environmentally friendly river embankment technique contained various factors such as oyster shells, effective microorganism, porous concrete and planting embankment block. To maximize greening effect, the seeds were arbitrarily sown. In addition, in order to analyze the effect of water quality purification after the planting, the samples were collected from each designated zone 1, 7 and 30 days after steeping in water. Then, the samples were analyzed in terms of seven test items such as SS, BOD, COD, T-N, T-P, pH, etc. on the basis of the test method for water pollution. The following conclusions were reached from the test result. As a result of analysis for water quality purification for the concrete block containing the effective microorganism, it was found that the values for SS, BOD, T-N and T-P for the sample taken after 30 days were lower than the initial values, which indicated that the water purification effect had been created. The result of the water quality purification analysis for the concrete block containing oyster shell showed that the values for SS, BOD, COD and T-P for the sample taken after 30 days were lower than the initial values which also indicated that it had been effective in water quality purification.

• Steel and Composite Structures
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• 제43권5호
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• pp.523-532
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• 2022

Turbocharger technology is one of the ways to survive in a competitive market that is facing increasing demand for fuel and improving the efficiency of vehicle engines. Turbocharging allows the engine to operate at close to its maximum power, thereby reducing the relative friction losses. One way to optimally understand the behavior of a turbocharger is to better understand the heat flow. In this paper, a 1.7 liter, 4 cylinder and 16 air valve gasoline engine turbocharger with compressible, viscous and 3D flow was investigated. The purpose of this paper is numerical investigation of the number of heat transfer in gasoline engines turbochargers under 3D flow and to examine the effect of different types of coatings on its performance; To do this, modeling of snail chamber and turbine blades in CATIA and simulation in ANSYS-FLUENT software have been used to compare the results of turbine with experimental results in both adiabatic and non-adiabatic (heat transfer) conditions. It should be noted that the turbine blades are modeled using multiple rotational coordinate methods. In the experimental section, we simulated our model without coating in two states of adiabatic and non-adiabatic. Then we matched our results with the experimental results to prove the validation of the model. Comparison of numerical and experimental results showed a difference of 8-10%, which indicates the accuracy and precision of numerical results. Also, in our studies, we concluded that the highest effective power of the turbocharged engine is achieved in the adiabatic state. We also used three types of SiO₂, Sic and Si₃N₄ ceramic coatings to investigate the effect of insulating coatings on turbine shells to prevent heat transfer. The results showed that SiO₂ has better results than the other two coatings due to its lower heat transfer coefficient.

• 한국식품저장유통학회지
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• 제20권5호
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• pp.621-627
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• 2013

본 연구는 울금을 이용한 다양한 가공제품의 개발 및 울금의 활용성 증대의 일환으로 울금 분말 첨가에 따른 만두피의 품질 특성에 대하여 알아보았다. 울금 분말을 1%, 3%, 5%, 7%로 함량을 달리하여 만두피를 제조하여 품질특성을 조사한 결과, 호화개시온도는 울금 분말의 첨가량이 증가될수록 점진적으로 증가하는 경향을 보였다. 최고점도, $95^{\circ}C$에서 점도 및 $95^{\circ}C$에서 15분간 유지한 후의 점도는 울금 분말의 첨가량이 증가함에 따라 낮아지는 것으로 나타났다. 만두피의 색도는 울금 분말 첨가량이 증가함에 따라 명도(L값)는 유의하게 감소하였으며, 적색도(a값)와 황색도(b값)는 각 시료간에 유의적으로 증가되었다. 조리특성에서 울금 분말을 첨가한 만두피는 대조군에 비해 중량, 부피, 수분흡수율 등이 모두 높게 나타났다. 만두피의 조직감은 울금 분말 첨가량이 증가될수록 경도, 응집성, 씹힘성 및 부착성은 높아졌으며, 탄력성은 감소하였다. 울금 만두피의 DPPH 라디칼 소거능은 각각 0.00%, 12.53%, 12.46%, 12.12%, 11.05%로 울금 분말 첨가군 간에는 유의적인 차이가 없었으나 이들 첨가군들은 대조군보다 유의적으로 높았다(p<0.05). 만두피의 관능검사 결과, 색깔은 울금 분말 3% 와 5% 첨가군이 기호도가 높게 나타났으며, 만두피의 향미 특성은 1%와 3% 첨가군이 높게 나타났다. 치아에 달라붙는 정도는 대조군에 비해 울금 분말 첨가시 높게 나타났으며, 만두피의 맛은 울금 분말 3% 첨가군이 가장 좋은 것으로 평가되었다. 전체적인 기호도는 울금 분말 3% 첨가군이 가장 높게 나타나 울금 분말을 일정량 첨가 시 관능적 특성이 향상되는 것으로 평가되었다. 이상의 결과로 볼 때 울금 분말을 첨가하여 만두피를 제조할 경우 울금 분말을 3% 첨가하는 것이 만두피의 색채감 향상, 맛의 증진과 전반적인 기호도면에서 가장 적절한 것으로 생각되며, 품질이 우수한 만두피를 제조할 수 있을 것으로 생각된다.