• 한국연소학회지
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• 제12권4호
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• pp.57-61
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• 2007

The aim of this study is to find out the condition that generates maximum $H_2$ through the calculation of equilibrium model with conditions of pyrolysis gases of Refuse Plastic Fuel(RPF). This study deals with the computational simulation of a RPF gasification using an equilibrium model based on minimization of the Gibbs free energy. An equilibrium analysis was carried out to determine species composition of Syngas in RPF gasification and reactions to variation of temperature, $O_2/Fuel$ ratio and Steam/Fuel ratio. Calculated results shows that hydrocarbons in pyrolyzed gas are converted to synthesis gas which is formed on hydrogen and carbon monoxide.

• Structural Engineering and Mechanics
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• 제53권3호
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• pp.589-605
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• 2015

The use of the rigid polyurethane foam (RPF) to strengthen buried structures against blast terror has great interests from engineering experts in structural retrofitting. The aim of this study is to use the RPF to strengthen the buried structures under blast load. The buried structure is considered to study the RPF as structural retrofitting. The Guowei model (Guowei et al. 2010) is considered as a case study. The finite element analysis (FEA) is also used to model the buried structure under shock wave. The buried structure performance is studied based on detonating different TNT explosive charges. There is a good agreement between the results obtained by both the Guowei model and the proposed numerical model. The RPF improves the buried structure performance under the blast wave propagation.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2005년도 추계 학술발표회 발표논문집
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• pp.195-198
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• 2005

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2006년도 추계학술발표논문집
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• pp.328-330
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• 2006

본 논문에서는 RPF를 제조하기 위한 공정을 확보하고 열량을 높이기 위한 조연제의 제조와 효율에 대하여 보고하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권12호
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• pp.1705-1711
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• 2014

The objective of this study was to evaluate the effect of ruminally protected amino acids (RPAAs) and ruminally protected fat (RPF) supplementation on ruminal fermentation characteristics (in vitro) and milk yield and milk composition (in vivo). Fourteen mid-lactating Holstein dairy cows (mean weight $653{\pm}62.59kg$) were divided into two groups according to mean milk yield and number of days of postpartum. The cows were then fed a basal diet during adaptation (2 wk) and experimental diets during the treatment period (6 wk). Dietary treatments were i) a basal diet (control) and ii) basal diet containing 50 g of RPAAs (lysine and methionine, 3:1 ratio) and 50 g of RPF. In rumen fermentation trail (in vitro), RPAAs and RPF supplementation had no influence on the ruminal pH, dry matter digestibility, total volatile fatty acid production and ammonia-N concentration. In feeding trial (in vivo), milk yield (p<0.001), 4% fat corrected milk (p<0.05), milk fat (p<0.05), milk protein (p<0.001), and milk urea nitrogen (p<0.05) were greater in cows fed RPAAs and RPF than the corresponding values in the control group. With an index against as 0%, the rates of decrease in milk yield and milk protein were lower in RPAAs and RPF treated diet than those of basal diet group (p<0.05). In conclusion, diet supplemented with RPAAs and RPF can improve milk yield and milk composition without negatively affecting ruminal functions in Holstein dairy cows at mid-lactating.

• Steel and Composite Structures
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• 제27권6호
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• pp.717-725
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• 2018

One of the most important design criteria in military tunnels and armoured doors is to resist the blast loads with minimum structural weight. This can be achieved by using steel sandwich panels. In this paper, the nonlinear behaviour of steel sandwich panels, with different core materials: (1) Hollow (no core material); (2) Rigid Polyurethane Foam (RPF); and (3) Vulcanized Rubber (VR) under free air blast loads, was investigated using detailed 3D nonlinear finite element models in Ansys Autodyn. The accuracy of the finite element model proposed was verified using available experimental test data of a similar steel sandwich panel tested. The results show the developed finite element model can be reliably used to simulate the nonlinear behaviour of the steel sandwich panels under free air blast loads. The verified finite element model was used to examine the different parameters of the steel sandwich panel with different core materials. The result shows that the sandwich panel with RPF core material is more efficient than the VR sandwich panel followed by the Hollow sandwich panels. The average maximum displacement of RPF sandwich panel under different ranges of TNT charge (1 kg to 10 kg at a standoff distance of 1 m) is 49% and 53% less than the VR and Hollow sandwich panels, respectively. Detailed empirical design equations were provided to quantify the maximum deformation of the steel sandwich panels with different core materials and core thickness under a different range of blast loads. The developed equations can be used as a guide for engineer to design steel sandwich panels with RPF and VR core material under a different range of free air blast loads.

• 한국작물학회지
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• 제40권3호
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• pp.382-390
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• 1995

우리나라 서남부평야지의 숙답과 간척답간 미질의 변이정도를 비교하기 위하여 각 지역별 표준 재배법에 따라 재배한 동률벼의 생육 및 수량특성과 미질특성을 비교 검토한 결과를 요약하면 다음과 같다. 1. 간장은 간척지에서는 지역간 변이폭이 1~2cm였으나 숙답에서는 4~5cm로 컸으며, m$^2$당 수수는 숙답에 비하여 간척답에서 많았으나, m$^2$당 수수, 등숙비율 및 천입중은 간척답에 비하여숙답에서 많거나 높은 편이었다. 2. 쌀수량은 숙답평균(511kg/10a)에 비하여 간척답이 12%정도 감수경향이었고, 숙답에서는 대전(511kg/10a)이, 간척답에서는 영암(530kg/10a)이 가장 높은 수량성을 보였다. 3. 현미 완전입율은 숙답의 쌀이 놓았고 미숙입과 피해입은 간척지 쌀이 많아, 외관상 미질은 숙답의 쌀이 우수한 경향이었다. 4. 전분함량과 알칼리 붕괴도는 숙답미에 미하여 간척답미가 높았고, 단백질과 지방 및 아밀로스 함량은 간척미가 낮았다. 5. 간척답미가 숙답미에 비하여 Ca, Mg,Na 및 K등 무기성분 함량이 높았고 Mg/K 및 Na/K 비율이 높은 경향이었다. 6. 호화개시온도는 지역간 및 숙답과 간척답간에 큰 차이는 없었으나 최고점도, 최저점도 및 강하정도는 대체로 간척답미가 높은 경향이었으며, 외관상 쌀품질은 숙답미에 비하여 간척답쌀이 떨어지는 편이었으나 식미는 약간 우수한 경향이었다.

• 한국식품저장유통학회지
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• 제11권4호
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• pp.565-568
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• 2004

대두 단백 필름 포장 방법이 쇠고기의 저장 중 품질에 미치는 영향을 측정하기 위하여 저장 중 중량 감소율, pH, TBARS, 미생물 수 (총균수) 등을 측정하였다. 쇠고기는 로즈마리 추출물을 첨가한 대두 단백 필름으로 포장 한 후 $4^{\circ}C$에 저장하였다. 중량 감소율은 대조구에 비해 포장재를 사용한 것이 현저하게 감소했으며 대두 단백 필름 포장(NPF)과 로즈마리 추출물을 첨가한 대두 단백 필름 포장(RPF)간의 차이는 보이지 않았다. 저장 중 pH의 변화에 있어서도 대조구에 비해 pH 증가가 적었다. 유지 산패 측정 결과, 저장 8일 후 RPF는 대조구와 비교하여 $86\%$의 저해를 보였다. RPF 포장은 또한 항산화 효과뿐만 아니라 항균 효과가 뛰어났는데 저장 기간 중 쇠고기의 총균수를 $90\%$ 이상 감소시켰다. 따라서, 쇠고기의 저장 중 품질 저하를 방지하기 위한 포장재로서 RPF 포장이 항산화 효과뿐만 아니라 항균 효과가 뛰어나 적절한 포장 방법이 될 수 있다고 판단된다.

• Archives of Plastic Surgery
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• 제46권4호
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• pp.336-343
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• 2019

Background Sternal rigid plate fixation (RPF) has been adopted in recent years in high-risk cases to reduce complications associated with steel wire cerclage, the traditional approach to sternal closure. While sternal RPF has been associated with lower complication rates than wire cerclage, it has its own complication profile that requires evaluation, necessitating a critical examination from a national perspective. This study will report the outcomes and associated risk factors of sternal RPF using a national database. Methods Patients undergoing sternal RPF from 2005 to 2016 in the American College of Surgeons-National Surgical Quality Improvement Program were identified. Demographics, perioperative information, and complication rates were reviewed. Logistic regression analysis was performed to identify risk factors for postoperative complications. Results There were 381 patient cases of RPF identified. The most common complications included bleeding (28.9%), mechanical ventilation >48 hours (16.5%), and reoperation/readmission (15.2%). Top risk factors for complications included dyspnea (odds ratio [OR], 2.672; P<0.001), nonelective procedure (OR, 2.164; P=0.010), congestive heart failure (OR, 2.152; P=0.048), open wound (OR, 1.977; P=0.024), and operating time (OR, 1.005; P<0.001). Conclusions Sternal RPF is associated with increased rates of three primary complications: blood loss requiring transfusion, ventilation >48 hours, and reoperation/readmission, each of which affected over 15% of the study population. Smokers remain at an increased risk for surgical site infection and sternal dehiscence despite RPF's purported benefit to minimize these outcomes. Complications of primary versus delayed sternal RPF are roughly equivalent, but individual patients may perform better with one versus the other based on identified risk factors.

• Korean Chemical Engineering Research
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• 제51권6호
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• pp.692-699
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• 2013

본 연구에서는 국내 상용 순환유동층 보일러에서 아역청탄과 혼소용 연료로 사용예정인 폐플라스틱 고형연료(RPF)의 열분해 반응특성을 규명하기 위해 열천칭 반응기를 이용하여 등온(350, 375, 400, 425, 450, 500, $850^{\circ}C$) 열분해 실험을 수행하였다. 등온 열분해 결과, 반응온도 구간 $375{\sim}450^{\circ}C$에서의 반응모델 변화는 관찰되지 않았으며, 12개 반응모델 중 1차 화학반응(F1)이 가장 적합한 반응모델로 판명되었다. 이때 Arrhenius 식을 사용하여 계산한 활성화에너지는 39.44 kcal/mol이었으며, Iso-conversional 방법을 적용할 경우 활성화에너지 평균값($0.5{\leq}X{\leq}0.9$ 구간)은 36.96 kcal/mol로 반응모델 결정 여부와 관계없이 유사한 값을 보였다. 한편 순환유동층보일러의 운전온도인 $850^{\circ}C$에서 RPF 입도(d) 변화에 따른 탈휘발 시간은 $t_{dev}=10.38d^{2.88}$으로 표현할 수 있었으며, 보일러 내부에서 RPF가 균일하게 연소되기 위해서는 연료 입도와 평균 분산 거리(x)가 $x{\leq}1.58d^{1.44}$의 상관관계를 만족하여야 함을 확인할 수 있었다.