• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.484-489
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• 2003

Purpose : To understand morphologic and hemodynamic variations in patients with pulmonary atresia with intact ventricular septum(PA/IVS), and to decide the best treatment modalities, we measured right ventricular volume, inflow, and outflow valvular annulus size in these patients and compared them with those of normal newborns. Methods : Eight patients with PA/IVS diagnosed by echocardiography from January to December 2001 were enrolled in this study. Among the total eight patients, five were male and three were female. The mean age of patients was 6.9 days(1-34 days), and the mean body weight was 3,343 gm (2,970-4,000 gm). Ten fullterm newborn infants with sepsis or hyperbilirubinemia without heart disease were enrolled as a control group. Echocardiographic and Doppler studies using Acuson Aspen (7Mh probe) were recorded on super-VHS videotape and later on, with review mode. We measured volumes of right and left ventricles, aortic, pulmonic, mitral and tricuspid valvular annulus sizes using an installed program, and then these parameters were compared with those of the control group. Results : Mean Z-value of tricuspid valvular annulus in PA/IVS was $-3.69{\pm}2.80$(-8.4--0.45), and tricuspid/mitral valvular annulus size ratio $0.68{\pm}0.15$(0.43--0.84). The more the tricuspid/mitral valvular annulus size ratio, the more Z-value of tricuspid valvular annulus(P=0.003, r=0.885). Those patients who underwent pulmonary valvuloplasty(balloon or surgical) had a tendency toward larger volume of the right ventricle, more Z-value of pulmonic and tricuspid valvular annulus, and more tricuspid/mitral valvular annulus size ratio than those patients who underwent a shunt operation. Conclusion : Compared to a measurement of the volume of the right ventricle, measurements of tricuspid/mitral valvular annulus size ratio and Z-value of tricuspid valvular annulus may be easier and better parameters to decide the treatment method and to predict prognosis in PA/IVS patients.

• FLOWER RESEARCH JOURNAL
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• v.19 no.4
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• pp.187-191
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• 2011

Rising soil temperature was effectively controled by shading net of 50% and cooled water to maintain average $18.8^{\circ}C$ (maximum $23^{\circ}C$), then shading net of 50% and ground water to maintain average $23.2^{\circ}C$ (max. $28.5^{\circ}C$), shading paint of 30% and shading net (50%) to maintain average $24^{\circ}C$ (max. $30^{\circ}C$) in that order. Alstroemeria 'Modena' most affected by shading and cooling water was better in shoot length as 95.9 cm and fresh weight as 67 g than those of other treatments. The production of cut flower was increased more 121% with treatment 50% shading net and cooling water, 59% with 50% shading net and ground water, and 65% with 30% shading paint than that of 50% shading net, respectively. Soil temperature was higher $8^{\circ}C$ with the plot of circulating warm water than untreated control plot. Alstroemeria 'Aspen', 'Modena', and 'Chanel' increased more plant growth such as plant height, fresh weight in warm water than in untreated control plot, but Alstroemeria 'Bordeaux' decreased plant height. Because of increasing plant growth, flower quality such as peduncle length, peduncle diameter, floret number and flower weight of 4 all cultivar was better in the plot of circulating warm water than untreated control plot. Also, the production of cut flower was increased the most in Alstroemeria 'Modena' by 38%, 'Aspen', 'Bordeaux', and 'Chanel' in that order.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.173-179
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• 2019

Cryogenic air separation unit produces various gases such as $N_2$, $O_2$, and Ar by liquefying air. The process also varies with diverse production conditions. The one for SNG production among them has lower efficiency compared to other air separation unit because it requires ultrapure $O_2$ with purity not lower than 99.5%. Among factors that reduce the efficiency of air separation unit, power consumption due to compress air and heat duty of double column were representatives. In this study, simulation of the air separation unit for SNG production was carry out by using ASEPN PLUS. In the results of the simulation, 18.21 kg/s of at least 99.5% pure $O_2$ was produced and 33.26 MW of power was consumed. To improve the energy efficiency of air separation unit for SNG production, the sensitivity analysis for power consumption, purities and flow rate of $N_2$, $O_2$ production in the air separation unit was performed by change of air boosting ratios. The simulated model has three types of air with different pressure levels and two air boosting ratio. The air boosting ratio means flow rate ratio of air by recompressing in the process. As increasing the first air boosting ratio, $N_2$ flow rate which has purity of 99.9 mol% over increase and $O_2$ flow rate and purity decrease. As increasing the second air boosting ratio, $N_2$ flow rate which has purity of 99.9 mol% over decreases and $O_2$ flow rate increases but the purity of $O_2$ decreases. In addition, power consumption of compressing to increase in the two cases but results of heat duty in double column were different. The heat duty in double column decreases as increasing the first air boosting ratio but increases as increasing the second air boosting ratio. According to the results of the sensitivity analysis, the optimum air boosting ratios were 0.48 and 0.50 respectively and after adjusting the air boosting ratios, power consumption decreased by approximately 7% from $0.51kWh/O_2kg$ to $0.47kWh/O_2kg$.

• Journal of Korean Society of Forest Science
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• v.105 no.1
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• pp.103-107
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• 2016

This study aims to select the most appropriate poplar clones for planting on short rotation coppice poplar plantations in a riparian area. The research investigated biomass production, nitrogen and carbon absorption with 2-year-old poplar (Populus spp.) clones including P. euramericana clone Eco28, P. deltoides hybrid clone 97-18, and P. alba ${\times}$ P. glandulosa hybrid clone 72-30. The average number of stems per stump was five and P. euramericana clone Eco28 had the greatest average number of live stems per stump with 5.9. The average stem diameter was 23.2 mm, and P. deltoides hybrid clone 97-18 achieved the largest average diameter with 25.4 mm. The average annual above-ground biomass production of Populus deltoides hybrid clone 97-18 was 16.1 ton/ha/year, followed by P. alba ${\times}$ P. glandulosa hybrid clone 72-30 and P. euramericana clone Eco28, 12.3 and 5.4 ton/ha/year, respectively. The average annual nitrogen uptake of poplar clones was 46.5 kg/ha/year. P. alba ${\times}$ P. glandulosa hybrid clone 72-30 had the highest average, 63.1 kg/ha/year. The average of annual carbon absorption was estimated 5.3 ton/ha/year and Populus deltoides hybrid clone 97-18 showed the best results with 7.7 ton/ha/year. Based on the results given above, P. deltoides hybrid aspen clone 97-18 is considered as the most suitable poplar clones for wood biomass production on riparian areas.

• Korean Journal of Clinical Pharmacy
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• v.22 no.4
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• pp.316-323
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• 2012

미숙아는 단백질 대사 속도가 빠르기 때문에 성장이 충분히 이루어질 수 있도록 ASPEN 가이드라인에서는 아미노산 초기용량을 1-2 g/kg/day로 투여하도록 권장하고 있다. 또한 최근 여러 연구에서 출생초기 고용량 (1.5-4 g/kg/day) 아미노산 투여에 대해 보고하고 있다. 이를 근거로 하여 삼성서울병원 신생아 중환자실에서도 2009년 6월부터 아미노산 초기용량을 0.5 g/kg/day에서 1.5~2 g/kg/day으로 증량하여 투여하고 있다. 본 연구에서는 신생아 중환자실에서 정맥영양요법을 받은 미숙아를 대상으로 고용량 아미노산 공급 효과를 평가하고자 하였다. 2009년 6월 기준으로 출생 후 48시간 이내에 0.5 g/kg/day로 아미노산을 투여 받은 저용량 환아군(38명: 대조군)과 1.5~2 g/kg/day로 투여 받은 고용량 환아군(38명: 시험군)의 전자의무기록을 후향적으로 검토하였다. 고용량 아미노산 공급 효과를 체중증가량 및 총 정맥영양기간, 경구 및 경장 영양 시작 시기, 재원기간으로 평가하였고, 안전성 평가를 위해 혈액화학검사 및 합병증을 조사하였다. 또한 두 군의 인구학적 및 주산기 인자, 영양 공급량 등에 대해 조사하였다. 두 군의 인구학적 및 주산기 인자는 재태기간에서만 차이를 보였으며, 시험군에서 재태기간이 길었다(p < 0.05). 초기 아미노산 용량만이 생후 28일간 일평균 체중증가량에 영향을 미치는 인자였으며 시험군의 일평균 체중증가량이 대조군보다 유의하게 큰 것으로 나타났다($12.6{\pm}4.5$ g/day vs $9.8{\pm}4.5$ g/day, p < 0.05). 목표 체중증가량에 도달한 비율도 시험군이 높았다(65.8% vs 47.4%). 총 공급열량, 총 정맥영양 공급 기간과 경구 및 경장 영양 시작 시기는 두 군간 차이가 없었으나 시험군에서 목표열량 도달시간, 신생아 중환자실 재원기간이 단축되었다(p < 0.05). 혈액화학검사 결과 및 대사성 산증, 호흡곤란증후군, 괴사성장염 발생은 두 군간 차이가 없었으며 고혈당 및 감염, 기관지폐이형증, 뇌실내출혈 발생률은 대조군에서 유의하게 높았다(p < 0.05). 연구 결과, 미숙아에서 출생 초기 고용량 아미노산 공급은 혈액화학검사 이상이나 합병증 없이 체중증가와 재원기간 감소에 효과가 있음을 확인하였다. 따라서 미숙아에 대한 출생초기 영양지원으로 1.5~2 g/kg/day 아미노산 공급은 안전하고 효과적이라고 사료된다.

• Journal of Mushroom
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• v.2 no.2
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• pp.97-101
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• 2004

The main objectives of this study were to fruit body of Phellinus linteus using liquid spawn. Highest mycelial growth and in vitro fruiting was observed when $180m{\ell}$ of water was added to 200g of brown rice in $1000m{\ell}$ PP bottle. Optimum inoculum amount was 100ml per bottle. Better mycelial growth and fruiting were observed when the amount of brown rice was lowered. For timber log culture of P. linteus, low contamination was observed when logs were sterilized for as low as 60 mins. But, best mycelial growth was observed when the logs were sterilized for 120mins. Among different log types, highest mycelial growth and fruiting were observed in oak and mulberry. Only few fruiting could be observed in birch, chestnut, alder, while no fruiting was produced in Aspen. Best fruiting was produced from isolate PH-211, although other isolates also produced few fruiting.

• Clean Technology
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• v.26 no.2
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• pp.96-101
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• 2020

In this paper, the commercial feasibility of trigeneration, producing heat, power, and hydrogen (CHHP) and using biogas derived from macroalgae (i.e., seaweed biomass feedstock), are investigated. For this purpose, a commercial scale trigeneration process, consisting of three MW solid oxide fuel cells (SOFCs), gas turbine, and organic Rankine cycle, is designed conceptually and simulated using Aspen plus, a commercial process simulator. To produce hydrogen, a solid oxide fuel cell system is re-designed by the removal of after-burner and the addition of a water-gas shift reactor. The cost of each unit operation equipment in the process is estimated through the calculated heat and mass balances from simulation, with the techno-economic analysis following through. The designed CHHP process produces 2.3 MW of net power and 50 kg hr^-1 of hydrogen with an efficiency of 37% using 2 ton hr^-1 of biogas from 3.47 ton hr^-1 (dry basis) of brown algae as feedstock. Based on these results, a realistic scenario is evaluated economically and the breakeven electricity selling price (BESP) is calculated. The calculated BESP is ¢10.45 kWh^-1, which is comparable to or better than the conventional power generation. This means that the CHHP process based on SOFC can be a viable alternative when the technical targets on SOFC are reached.

• Journal of the Korean Institute of Gas
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• v.24 no.1
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• pp.17-22
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• 2020

Light Naphtha is distillated from crude oil unit and separated into the methane, ethylene and propylene by boiling point difference in sequence. This separation is conducted using a series of binary-like columns. This separation method is known that the energy consumed in the reboiler is used to separate the heaviest components and most of this energy is discarded as vapor condensation in the overhead cooler. In this study, the first two columns of the separation process are replaced with the Petlyuk column. A structural design was exercised by the stage computation with ideal tray efficiency in equilibrium condition. Compared with the performance of a conventional system of 3-column model, The design outcome shows that the procedure is simple and efficient because the composition of the liquid component in the column tray was designed to be similar to the equilibrium distillation curve. The performance of the new process indicates that an energy saving of 12.1% is obtained and the cost savings of 44 million won per day based on gross domestic product is reduced under same total number of trays and the initial investment cost is saved.

• Journal of Ocean Engineering and Technology
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• v.37 no.2
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• pp.58-67
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• 2023

While extensive research is being conducted to reduce greenhouse gases in industrial fields, the International Maritime Organization (IMO) has implemented regulations to actively reduce CO₂ emissions from ships, such as energy efficiency design index (EEDI), energy efficiency existing ship index (EEXI), energy efficiency operational indicator (EEOI), and carbon intensity indicator (CII). These regulations play an important role for the design and operation of ships. However, the calculation of the index and indicator might be complex depending on the types and size of the ship. Here, to calculate the EEDI of two target vessels, first, the ships were set as Deadweight (DWT) 50K container and 300K very large crude-oil carrier (VLCC) considering the type and size of those ships along with the engine types and power. Equations and parameters from the marine pollution treaty (MARPOL) Annex VI, IMO marine environment protection committee (MEPC) resolution were used to estimate the EEDI and their changes. Technical measures were subsequently applied to satisfy the IMO regulations, such as reducing speed, energy saving devices (ESD), and onboard CO₂ capture system. Process simulation model using Aspen Plus v10 was developed for the onboard CO₂ capture system. The obtained results suggested that the fuel change from Marine diesel oil (MDO) to liquefied natural gas (LNG) was the most effective way to reduce EEDI, considering the limited supply of the alternative clean fuels. Decreasing ship speed was the next effective option to meet the regulation until Phase 4. In case of container, the attained EEDI while converting fuel from Diesel oil (DO) to LNG was reduced by 27.35%. With speed reduction, the EEDI was improved by 21.76% of the EEDI based on DO. Pertaining to VLCC, 27.31% and 22.10% improvements were observed, which were comparable to those for the container. However, for both vessels, additional measure is required to meet Phase 5, demanding the reduction of 70%. Therefore, onboard CO₂ capture system was designed for both KCS (Korea Research Institute of Ships & Ocean Engineering (KRISO) container ship) and KVLCC2 (KRISO VLCC) to meet the Phase 5 standard in the process simulation. The absorber column was designed with a diameter of 1.2-3.5 m and height of 11.3 m. The stripper column was 0.6-1.5 m in diameter and 8.8-9.6 m in height. The obtained results suggested that a combination of ESD, speed reduction, and fuel change was effective for reducing the EEDI; and onboard CO₂ capture system may be required for Phase 5.

• Korean Chemical Engineering Research
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• v.62 no.2
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• pp.163-172
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• 2024

In this study, two different scenarios for ammonia liquefaction in the green ammonia manufacturing process were proposed, and the economic-feasibility and environmental impact of each scenario were analyzed. The two liquefaction processes involved gas-liquid separation before cooling at high pressure (high pressure cooling process) or after decompression without the gas-liquid separation (low pressure cooling process). The high-pressure cooling process requires higher capital costs due to the required installation of separation units and heat exchangers, but it offers relatively lower total utility costs of 91.03 $/hr and a reduced duty of 2.81 Gcal/hr. In contrast, although the low-pressure cooling process is simpler and cost-effective, it may encounter operational instability due to rapid pressure drops in the system. Environmental impact assessment revealed that the high-pressure cooling process is more environmentally friendly than the low-pressure cooling process, with an emission factor of 0.83 tCO₂eq less than the low-pressure cooling process, calculated based on power usage. Consequently, the outcomes of this study provide relevant scenario and a database for green ammonia synthesis process adaptable to various process conditions.