• 한국도로학회논문집
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• 제10권4호
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• pp.41-52
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• 2008

본 연구는 박리방지 첨가제를 혼입한 아스팔트 혼합물의 수분민감성에 대한 특성 평가 방안을 제시하고자, 기존의 수침 시험을 개선한 3가지 종류($H_c$, $V_s$, F-T)의 수침 방법을 통하여 생석회, 소석회, 1종의 액상 박리방지 첨가제를 혼입한 각 아스팔트 혼합물에 대한 수분민감성의 거동 특성을 분석하였다. 실험방법은 AASHTO TP-9에 규정된 간접인장시험(Indirect Tensile Test, IDT)을 통한 크리프시험 (Creep Test), 회복탄성계수시험(Resilient Modulus Test) 및 강도시험(Strength Test)을 수행하였다. 분석방법으로는 미국 플로리다 대학의 Roque에 의해 제안된 에너지비(Energy Ratio, ER) 개념을 사용하여 박리방지제의 사용에 따른 효과 및 수분민감도 특성을 평가하였다(Roque, 2004). 시험결과, 수분처리 방법 에 따른 아스팔트 흔합물의 물성 변화뿐만 아니라 박리 방지 첨가제에 따른 물성 변화가 현저하게 나타났다. 또한 누적 수분 손상에 의해 발생되는 균열에 대한 저항성이 각 첨가제 및 수분처리 방법에 따라 변화됨을 나타내었다. 이를 토대로 Energy Ratio를 분석한 결과 약 $10{\sim}30%$ 정도의 균열 저항성 변화가 나타났다.

• 한국식품과학회지
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• 제34권5호
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• pp.818-823
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• 2002

전통적인 유과제조공정에서 반데기의 성형, 건조, 수분조절과 부재료의 첨가가 유과의 특성에 미치는 영향을 결정하였다. 반데기의 숙성에 따른 반데기의 페이스트 점도는 숙성기간 2일에 최대점도 300 RVU이였고 숙성기간이 길어질수록 최대점도가 감소하였다. 수침을 거친 반데기의 기공은 내부에 균일하게 분포되어 있었으나 숙성기간이 길어짐에 따른 크기와 분포의 변화는 없었다. 전통적인 유과제조 공정으로 제조한 반데기의 최적 수분함량 $14{\sim}17%$에서 튀겼을 때 팽화도와 조직감은 좋았다. 유과원료의 부재료로 대두즙과 소주를 첨가한 찹쌀반죽으로 제조한 반데기를 튀긴 유과의 팽화도와 조직감이 우수하였다. 소주는 유과의 팽화에 영향을 미치고 대두즙은 조직감을 부드럽게 하였다. 유과(유탕팽화 펠릿)의 내부에는 큰 기공이 분포하며 외부에는 작은 기공이 세밀하게 분포되어 있었다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.404-408
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• 2009

The liquid desiccant air-conditioning system has been proposed as an alternative to the conventional vapor compression cooling systems to control air humidity. The complete system of liquid desiccant air-conditioning system is consisted two main components those are humidifier (regeneration) and dehumidifier. Humidifier part is connected to the load when summer season which is the air condition is hot and humid have to be turned into comfort condition on human. This paper purpose is performances study of air flow rate effect on a structured packed tower on cooling and dehumidifier system using liquid lithium chloride as the desiccant. Experimental apparatus used in this present study is consisted of three components those are load chamber, packed tower and chiller. Load chamber’s volume is $40m^3$, and packed tower dimension is cubic with length 0.4m occupied with packed column. Totally, 15 experimental has done using 5 times repeat on each variable of air velocity that varying on 2m/s, 3m/s and 4m/s with other conditions are controlled. Air inlet initial temperature and relative humidity are set respectively on $30^{\circ}C$ and 52%, desiccant flow rate is 0.63 kg/s, desiccant temperature is $10^{\circ}C$ and desiccant concentration is 0.4. The result of this study shows that averagely, the moisture removal rate and the heat transfer rate are influenced by the air velocity. Higher air velocity will increase the heat transfer and decreasing the moisture removal rate. At adiabatic condition the air velocity of 2 m/s respectively is having the higher moisture removal rate acceleration then the air velocity of 3m/s and 4 m/s until the steady state condition.

• 한국수산과학회지
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• 제34권4호
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• pp.309-314
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• 2001

소형 적색육어의 소비기호에 부정적으로 작용하고 있는 잔뼈를 연화시켜 제거하고 비린내를 저감시키기 위하여 대표적인 소형 적색육어인 꽁치, Cololabis saira를 김치양념과 유기산 그리고 미강을 첨가하여 $5\pm0.5^{\circ}C$에서 60일 동안 숙성시키면서 15일 간격으로 숙성 중 화학적 변화를 검토하였다. 마른간이 물간에 비해 염침투도 및 탈수도가 높아 조미양념과의 평형이 15일 정도 빨랐으며, 그로 인해 숙성 중 pH가 높고, 휘발성염기질소함량과 TBA가가 낮아 조미숙성제품 제조시 염 첨가방법은 마른간이 적합하였다. 마른간에 미강을 첨가한 제품은 첨가하지 않은 제품에 비해 미강에 함유되어 있는 아미노산이 제품으로 이행되어 정미성분의 함량을 나타내는 아미노태질소가 높았고, 단백질 산패억제 및 미강의 carotenoid와 tocopherol 둥의 항산화물질에 의한 지질산화 억제효과도 있어 저이용 자원의 활용 증대측면에서 상업적 제품화가 기대된다.

• 설비공학논문집
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• 제14권4호
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• pp.324-331
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• 2002

The characteristics of moisture ventilation in a dry room are studied numerically The behaviors of moisture ventilation are analyzed by varying the aspect ratio of the horizontal plane and for various positions of the outlets in the room. Three different ventilation efficiencies have been used to examine the effect of the longitudinal arrangement of outlets and transverse arrangement of outlets for each aspect ratio on ventilation inside the room. It is shown that the ventilation efficiency in the dry room can be improved by arranging the outlets transversely in the cases that the aspect ratio is less than three and longitudinally in the cases that it is greater than four.

• 설비공학논문집
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• 제1권2호
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• pp.162-172
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• 1989

The steady one dimensional heat flow method was used for the measurement of thermal conductivity of kaolin. The effects of the classification, density and moisture content on the thermal conductivity were studied experimentally for the 9 classes of kaolin in Korea. As the results of this study, it was found that the classification did not effect the thermal conductivity, and the conductivity increased as the density and moisture content increased. The correlation equation of the thermal conductivity as a function of the density increase rate was found and the values for the thermal conductivity as a function of moisture content were recommended.

• 설비공학논문집
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• 제27권12호
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• pp.645-651
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• 2015

This paper presents an experimental study on the freeze drying process for poly ${\gamma}$ glutamic acid. The physical properties of poly ${\gamma}$ glutamic acid are measured during the freeze-drying process. The moisture contents of poly ${\gamma}$ glutamic acid according to the glass transient temperature are obtained by DSC (Differential Scanning Calorimetry) analysis. The end point of primary drying for the poly ${\gamma}$ glutamic acid with a thickness of 3 mm is obtained by measuring the thickness of the dried layer, the amount of moisture evaporation, the moisture content, and the pressure in the drying vacuum chamber during the freeze-drying process. By considering the variation in the glass transient temperature with respect to the moisture content of the material, a control schedule for the heating plate temperature is suggested during the secondary drying process.

• 설비공학논문집
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• 제26권2호
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• pp.55-60
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• 2014

The present study has been conducted to develope a heating system for a green house with heat from underground air at Jeju Island. The temperature of the air deposited in the underground is $16{\sim}18^{\circ}C$ throughout the year, and it also has a large amount of moisture. Therefore, the air could not directly used for the heating of a green house. In this study, a heat pump with dehumidification function has been developed, which consisted of three evaporators, where the moisture removal occurs, accompanied by temperature drop. The dropped temperature is recovered, while passing through a series condenser. The air temperature increased from $17^{\circ}C$ to 35 with a 2.1 kg/h of moisture removal rate. The developed system moisture removal performance shows 0.91 kg/kWh.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2270-2273
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• 2003

Fuzzy logic control has been widely implemented in air conditioning and ventilation systems which has uncertainty or high robust system. Since the dynamic behaviors of the systems contain complexity and uncertainty in its parameters , several fuzzy logic controllers had been implemented to control room temperature in the field of air conditioning system. In this paper, the fuzzy logic control has been developed to control room temperature and humidity in the precision air conditioning systems. The nonlinear mathematical model was formulated using energy and continuity equations. MATLAB was used to simulate the fuzzy logic control of the multi-variable air conditioning systems. The simulation results show that fuzzy logic controller can reduce the steady-state errors of the room temperature and relative humidity in multivariable air conditioning systems. The offset are less than 0.5 degree Celsius and 3 percent in relative humidity respectively under random step disturbance in heating load and moisture load respectively

• Journal of the Korean Wood Science and Technology
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• 제17권3호
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• pp.67-81
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• 1989

This experiment was carried out to know the mothod of changing the step of moisture content schedule with time in conventional kiln drying. For the purpose of this object. we made drying model by applying the moisture diffusion model by J.FSiau(1984) to average moisture content equation by J.Crank(1956) derived it from Fick's second law. And to verify this method of drying model. 2.5cm-thick boards and 5.0cm-thick dimension lumbers of Pinus densiflora were kiln-dried with the schedule of T11-C3 and T10-C4, respectively. And then the drying rates were investigated and compared with those calculated from drying model. The results obtained were as follows 1. Average drying rate and total drying time of board to dry to 6.5% moisture content were 0.64%/hr and 109hr., and those of dimension lumber to dry to 8.3% moisture content were 0.4%/hr. and 162hr., respectively. 2. The moisture content of shell and core decreased by equalizing treatment and increased by conditioning treatment both on board and dimension lumber. But the moisture gradient was lower after conditioning than after equalizing. 3. As the drying was proceeded, the transverse bound water diffusion coefficient all but linearly decreased, the water vapor diffusion coefficient abruptly curvilinearly increased, while the transverse diffusion coefficient curvilinearly decreased both on board and dimension lumber. But each of diffusion coefficients on board was larger than that on dimension lumber. 4. Compared to experimential drying rate of board. theoretical drying rate was larger at 30.0%-21.8% moisture content range and was similiar at 21.8%-5.4% moisture content. And in case of dimension lumber, the drying rate was similiar at 30.0%-16.1% moisture content range but theoretical drying rate was much lower at 16.1%-8.3% moisture content range. 5. The possibility of adapting this drying model to changing the moisture content schedule step with time was in the range of 21.8%-5.4% moisture content on board. And in the case of dimension lumber that was in the range of 30.0%-16.1% moisture content.