• 한국물환경학회지
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• 제30권5호
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• pp.486-490
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• 2014

Industrial use of microwave heating as an alternative to conventional heating is becoming popular mainly due to dramatic reductions in reaction time. Therefore, this work experimentally determined the effect of microwave irradiation on ammonia nitrogen removal in wastewater. The effects of air flow rate (0.3~0.9 L/min), treatment temperature ($70{\sim}100^{\circ}C$), and initial pH (9~11) were characterized. As the air flow rate increased from 0.3 to 0.9 L/min, the ammonia removal rate constant (k) increased from -0.6642 to $-1.0755min^{-1}$. As the temperature increased from 70 to $100^{\circ}C$, k increased -0.0338 to $-1.0755min^{-1}$. As the pH increased from 9 to 11, k increased -0.2443 to $-1.0755min^{-1}$. Ammonia removal was strongly dependent on temperature and pH rather than air flow rate. The results show that microwave irradiation is effective in ammonia nitrogen removal in wastewater due to advantages of fast and effective processing.

• 한국작물학회지
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• 제10권
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• pp.73-77
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• 1971

본 실험은 소맥품종 Weibull's Svenno종자(수분함량 11.3%)에 감마선과 속중성자를 조사한후 일정기간의 저장효과를 저장시 온도와 관련시켜 조사한 결과이다. 감마선이나 속중성자조사에 의하여 모두 묘생육은 저장기간의 연장에 따라서 감소되었고 선량구에서는 그 정도가 더욱 크게 나타났다. 저장온도효과에 대한 묘생육장해는 높은온도(4$0^{\circ}C$)구에서 크게 보였다. 이의 결과로서는 명확한 저장효과를 인정할 수 있었다.

• 한국식품영양과학회지
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• 제32권6호
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• pp.864-869
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• 2003

방사선 조사식품의 수용성 비타민에 대한 안정성을 확인하기 위하여 방사선 조사에 가장 민감하다고 알려져 있는 수용성 비타민 B$_1$과 비타민 C를 택해 닭 가슴살과 딸기와 감귤에 방사선을 조사한 후 닭 가슴살에서 비타민 B$_1$과 딸기와 감귤에서 비타민 C의 함량변화를 조사하였다. 닭가슴살 부위의 경우 감마선 조사시 온도를 냉장과 냉동 상태로 달리 하여 조사한 후 조리 방법을 가열조리와 마이크로웨이브 조리로 달리한 결과 티아민 함량의 손실은 감마선 조사선량에 따른 영향도 관찰되었지만 냉장, 냉동 등과 같은 조사시의 온도 상태도 크게 영향을 미치는 것으로 나타났다. 귤의 비타민 C 함량은 5 kGy까지는 조사에 의한 손실이 나타타지 않았고, 딸기의 비타민 C 함량은 3 kGy의 낮은 조사선량 범위 내에서는 조사선량에 의한 영향보다는 딸기의 품종에 따른 함량이 최종비타민 함량을 더 좌우하는 것으로 나타났다. 따라서 감마선 조사시 비타민의 함량의 변화에는 일정 범위의 조사선량하에서는 조사시의 온도나 식품의 조성 등이 더 큰 인자로 작용할 수 있으며, 가열에 의한 손실도 냉장보다는 냉동 처리 후 조사함에 의해 감소시킬 수 있는 가능성을 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 전기설비전문위원
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• pp.43-45
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than 80$[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation Power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study, the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• 한국염색가공학회지
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• 제27권2호
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• pp.119-125
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• 2015

The effects of e-beam irradiation on water-repellency and washing durability of water-repellent finished chemically-recycled PET(CR-PET) fabrics were investigated. As results, more doses of e-beam irradiation damaged the fabric surface more severely. It was thought because the high densed energy was formed, where the more e-beam was converged. The contact angle measurement showed that as the dose of e-beam irradiation increased, water wettability of the CR-PET fabric increased slightly. It was thought to be due that the surface etching by e-beam irradiation let water droplet permeate into the fabric surface better. The concentration of the water-repellent finishing agent was more important factor than curing temperature as finishing parameter. It was considered because the water-repellent finishing agent used in this study got to cure sufficiently at low temperature. Consequently, e-beam irradiation improved the washing durability of water-repellent finishing on the CR-PET fabrics.

• Fisheries and Aquatic Sciences
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• 제18권2호
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• pp.115-121
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• 2015

This study was conducted to confirm quality properties of sterilized Ganjang-gejang (marinated crab Portunus trituberculatus) with Korean soy sauce using by gamma irradiation and to improve quality of sterilized Ganjang-gejang. The Ganjang-gejang was irradiated at dose of 3, 6, 9, 12, and 15 kGy by gamma irradiation and there was evaluated in microbiological, physicochemical, and sensory properties. Total aerobic bacteria and fungi contents of non-irradiated samples were about 6 and 4 log CFU/g level, respectively. Gamma-irradiated samples at above 9 kGy did not contain aerobic bacteria or fungi at detection limit less than 2 log CFU/g, but sensory scores were significantly decreased depending on the irradiation dose. To improve the sensory qualities of gamma-irradiated Ganjang-gejang, the temperature was adjusted during sample irradiation. When samples were irradiated under freezing temperatures, especially on dry ice, the TBARS and the deterioration of sensory qualities of Ganjan-Gejang were reduced. Different odor patterns were observed among samples, as observed using electronic nose analysis system. The results of this study indicated that treatment with irradiation under low temperatures may help to preparing high-quality Ganjang-gejang.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2616-2628
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• 2021

The results of effective irradiation swelling in a wide range of burnup levels are numerically obtained for an inert matrix fuel, which are verified with DART model. The fission gas swelling of fuel particles is calculated with a mechanistic model, which depends on the external hydrostatic pressure. Additionally, irradiation and thermal creep effects are included in the inert matrix. The effects of matrix creep strains, external hydrostatic pressure and temperature on the effective irradiation swelling are investigated. The research results indicate that (1) the above effects are coupled with each other; (2) the matrix creep effects at high temperatures should be involved; and (3) ranged from 0 to 300 MPa, a remarkable dependence of external hydrostatic pressure can be found. Furthermore, an explicit multi-variable mathematic model is established for the effective irradiation swelling, as a function of particle volume fraction, temperature, external hydrostatic pressure and fuel particle fission density, which can well reproduce the finite element results. The mathematic model for the current volume fraction of fuel particles can help establish other effective performance models.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2148_2149
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• 2009

Development of renewable energy is promoted to achieve sustainability. So researchers are seeking and developing a new, clean, safe and renewable energy. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC power vary with module temperature, it is necessary to study the characteristics of photovoltaic P-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic P-V according to the module temperature. The results show that it seems that when the module temperature increases, the DC power increases. But actually, because when the irradiation increases, the DC power increases, the result of the relationship between DC power and the module temperature of solar cell will be effects by the increasing irradiation.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2150_2151
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• 2009

Solar, as an ideal renewable energy, has inexhaustible, clean and safe characteristics. However, solar energy is an extreme intermittent and inconstant energy source. In order to improve the photovoltaic system efficiency and utilize the solar energy more fully, and the DC current vary with module temperature, it is necessary to study the characteristics of photovoltaic I-V according to the external factors. This paper presents the analysis of characteristics of photovoltaic I-V according to the module temperature. The results show that it seems that when the module temperature increases, the DC current increases. But actually, because when the irradiation increases, the DC current increases, the result of the relationship between DC current and the module temperature of solar cell will be effects by the increasing irradiation.

• 센서학회지
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• 제26권3호
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• pp.168-172
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• 2017

A nondispersive infrared (NDIR) ethanol gas sensor was prototyped with ASIC implemented thermopile sensor, which included a temperature sensor and two ellipsoidal waveguide structures. The temperature dependency of the two ethanol sensors (with partially blocked and intact structures) has been characterized. The two ethanol gas sensors showed linear output voltages initially when varying the ambient temperature from 253 K to 333 K. The slope of the temperature sensor presented a constant value of 15 mV/K. After temperature compensation, the ethanol gas sensor estimated ethanol concentrations with larger errors of 20 to 25% below 200 ppm. However, the estimation errors were reduced to between -10 and +1 % from 253 K to 333 K above 200 ppm ethanol gas concentration in this research.