• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.7
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• pp.1209-1215
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• 2022

The selective catalytic reduction (SCR) is known as a very efficient method to reduce nitrogen oxides (NOx) and the catalyst performs reduction from nitrogen oxides (NOx) to nitrogen (N₂) and water vapor (H2O). The catalyst, which is one of the factors determining the performance of the nitrogen oxide (NOx) ruduction method, is known to increase catalyst efficiency as cell density increases. In this study, the reduction characteristics of nitrogen oxides (NOx) under various engine loads investigated. A 100CPSI(60Cell) catalysts was studied through a laboratory-sized simulating device that can simulate the exhaust gas conditions from the power generation engine installed in the training ship SEGERO. The effect of 100CPSI(60Cell) cell density was compared with that of 25.8CPSI(30Cell) cell density that already had NOx reduction data from the SCR manufacturing. The experimental catalysts were honeycomb type and its compositions and materials of V₂O₅-WO₃-TiO₂ were retained, with only change on cell density. As a result, the NOx concentration reduction rate from 100CPSI(60Cell) catalyst was 88.5%, and IMO specific NOx emission was 0.99g/kwh satisfying the IMO Tier III NOx emission requirement. The NOx concentration reduction rate from 25.8CPSI(30Cell) was 78%, and IMO specific NOx emission was 2.00g/kwh. Comparing the NOx concentration reduction rate and emission of 100CPSI(60Cell) and 25.8CPSI(30Cell) catalysts, notably, the NOx concentration reduction rate of 100CPSI(60Cell) catalyst was 10.5% higher and its IMO specific NOx emission was about twice less than that of the 25.8CPSI(30Cell) catalysts. Therefore, an efficient NOx reduction effect can be expected by increasing the cell density of catalysts. In other words, effects to production cost reduction, efficient arrangement of engine room and cargo space can be estimated from the reduced catalyst volume.

• The Journal of Korean Institute of Next Generation Computing
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• v.15 no.4
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• pp.18-29
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• 2019

A dynamic adaptive streaming server consumes high processor power because it handles a large amount of transcoding operations at a time. For this purpose, multi-processor architecture is mandatory for which effective transcoding task distribution strategies are essential. In this paper, we present the design and implementation details of the transcoding workload distribution schemes at a 2-tier (frontend node and backend node) transcoding server. For this, we implemented four schemes: 1) allocation of transcoding tasks to appropriate back-end nodes, 2) task scheduling in the back-end node and 3) the communication between front-end and back-end nodes. Experiments were conducted to compare the estimated and the actual power consumption in a real testbed to verify the efficacy of the system. It also proved that the system can reduce the load on each node to optimize the power and time used for transcoding.

• The Korean Journal of Emergency Medical Services
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• v.10 no.2
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• pp.53-62
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• 2006

Purpose: There has been an increase in the number of prehospital cardiac arrests due to the increasing number of cardiovascular diseases and the increase in the average age of the population. We performed this study to identify the proper resuscitation technique and AED to be used to increase the survival rate in prehospital cardiac arrests. Methods: This studied 159 victims with prehospital cardiac arrests(VF or VT rhythm) by EMT's Reports from January to August, 2005. Results: 108 of 159 victims(67.9%) were shocked by AED. Eighty of 159 victims(50.9%) were recorded with AED shock in prehospital cardiac arrests. A number of shocks is averaged 2.19; 46.2% of one-shock and 86.1% of 1-3 shock. EMS first-tier response interval from time of dispatch to scene arrival was 5.88 minutes, from scene arrival to scene start was 7.36 minutes, from scene start to hospital admission was 9.91 minutes and from scene arrival to AED shock was 6.84 minutes. EMT provided advanced care to prehospital cardiac arrests: 97.5% in CPR, 10.1% in advanced airway management, 67.9% in AED shock. Conclusion: With the increase in cardiovascular disease and old age, the number of prehospital cardiac arrests has risen gradually. However, there were lack of CPR by bystander, defibrillation and advanced cardiac life support(ACLS) in prehospital stage. To improve the adequacy of basic life support and to increase the performance of ACLS, especially AED, we must create challenges to develop new protocols in prehospital care.

• Korean Journal of Clinical Pharmacy
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• v.28 no.2
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• pp.88-94
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• 2018

Background: We strived to evaluate the status of nivolumab use and associated factors on the clinical efficacy of the drug. Methods: The study was retrospectively conducted in patients who had been administered nivolumab at least once at the cancer center of Seoul National University Hospital from June 2015 to April 2017. Data were collected from electronic medical records. A medication-use evaluation was performed based on the American Society of Health-System Pharmacists mediation-use guidelines. Results: Sixty-six of the 74 patients (89.2%) showed indications approved for nivolumab use by the Korean Ministry of Food and Drug Safety (MFDS; n=55) or the US Food and Drug Administration (FDA; n=11). Approximately 73.0% of the patients were administered the approved dose of 3 mg/kg but 25.7% were administered an unapproved fixed dose of 100 mg. The overall response rate was 21.7%, and the response rate of non-small cell lung cancer patients, who accounted for the largest number of indications, was 18.8%. Adverse reactions were found in 90.1% of the patients and were mostly mild (86%). The expression of programmed death-ligand 1 (PD-L1) was analyzed as a factor affecting treatment response (p=0.028, odds ratio [OR]=11.331). Conclusion: PD-L1 expression was found to affect treatment response. However, caution is required while using an unapproved dosage and in the absence of monitoring for effectiveness and safety. Therefore, an effective protocol or instruction manual for the proper use of nivolumab should be considered.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.445-452
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• 2018

The field of agriculture, forestry, and other land-use (AFOLU) is concerned with greenhouse emissions of agriculture (crop and livestock), as is the field of land-use, land-use change, and forestry (LULUCF). The 1996 IPCC guideline and the 2006 IPCC guideline are used in combination for calculation of greenhouse gas emission from the agricultural sector, and the 2003 IPCC guideline is used for that from the land-use sector. In this research, we analyzed GHG emissions of the cropland sector in AFOLU based on the 2006 IPCC guideline. The results showed that GHG emissions of 1990 was $-504Gg{\cdot}CO_2-eq$, while that of the last year was $2,871Gg{\cdot}CO_2-eq$. Compared with the 2003 methodology, total emissions according to the 2006 IPCC was lower except in 1997 and 2003. This trend is due to difference of analyzed emission sources, lower default values, and global warming potential by the 2006 IPCC. The results are estimated using limited data at the Tier 1 level and the first issue to be solved is the activity data from the land-use change matrix. Although this result should be improved, it can be used as the basis for calculating GHG emissions of the AFOLU sector.

• The Journal of Korean Institute of Next Generation Computing
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• v.14 no.5
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• pp.40-52
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• 2018

Solid state drive (SSD) cache technologies that are used as a second-tier cache between the main memory and hard disk drive (HDD) have been widely studied. The SSD cache requires a new prefetching scheme as well as cache replacement algorithms. This paper presents a prefetching scheme for a storage-class cache using SSD. This prefetching scheme is designed for the storage-class cache and based on a long-term scheduling in contrast to the short-term prefetching in the main memory. Traditional prefetching algorithms just consider only read, but the presented prefetching scheme considers both read and write. An experimental evaluation shows 2.3% to 17.8% of hit rate with a 64GB of SSD and the 4GiB of prefetching size using an I/O trace of 14 days. The proposed prefetching scheme showed significant improvement of cache hit rate and can be easily implemented in storage-class cache systems.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.258-266
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• 2023

This study analyzed methodologies for estimating carbon stocks of perennial woody crops and the research cases in overseas countries. As a result, we found that Australia, Bulgaria, Canada, and Japan are using the stock-difference method, while Austria, Denmark, and Germany are estimating the change in the carbon stock based on the gain-loss method. In some overseas countries, the researches were conducted on estimating the carbon stock change using image data as tier 3 phase beyond the research developing country-specific factors as tier 2 phase. In South Korea, convergence studies as the third stage were conducted in forestry field, but advanced research in the agricultural field is at the beginning stage. Based on these results, we suggest directions for the following four future researches: 1) securing national-specific factors related to emissions and removals in the agricultural field through the development of allometric equation and carbon conversion factors for perennial woody crops to improve the completeness of emission and removals statistics, 2) implementing policy studies on the cultivation area calculation refinement with fruit tree-biomass-based maturity, 3) developing a more advanced estimation technique for perennial woody crops in the agricultural sector using allometric equation and remote sensing techniques based on the agricultural and forestry satellite scheduled to be launched in 2025, and to establish a matrix and monitoring system for perennial woody crop cultivation areas in the agricultural sector, Lastly, 4) estimating soil carbon stocks change, which is currently estimated by treating all agricultural areas as one, by sub-land classification to implement a dynamic carbon cycle model. This study suggests a detailed guideline and advanced methods of carbon stock change calculation for perennial woody crops, which supports 2050 Carbon Neutral Strategy of Ministry of Agriculture, Food, and Rural Affairs and activate related research in agricultural sector.

• The Research Journal of the Costume Culture
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• v.25 no.2
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• pp.145-158
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• 2017

This paper aims to analyze the characteristics of the contemporary Chinese fashion market and the competitiveness of Korean fashion brands in China. Fashion professionals experienced in both the Korean and Chinese fashion markets participated to investigate the Shanghai market and consumers. The results of in-depth interviews show that Shanghai is the most favorable city among Tier 1 cities for Korean fashion brands planning on entering into the Chinese market. Shanghai consumers are open to international brands and highly prefer newness in fashion. Contemporary menswear was selected as a potentially big market due to the increase of unique, young, upper-middle-class male consumers. The Korean fashion brands' strength is that they are capable of satisfying Shanghai consumers with excellent product planning and sensory design capabilities. Their disadvantage is that their brand recognition is weaker than that of global and international brands, and their ability to localize to the Chinese market is weak. The opportunity comes is from the Korean Wave, which is a positive for Korea's products and has good geographical access. The threat is that the Shanghai market is fiercely competitive; having access to many worldwide brands, and the competitiveness of Chinese brands is on the rise. To enter the Shanghai market, creative design ability, trendy product development, skill, and appropriate PR methods such as using Korean culture contents would be required to satisfy the young, powerful consumers in Shanghai.

• Ocean and Polar Research
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• v.42 no.2
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• pp.171-178
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• 2020

R/V EARDO, commissioned in 1992, has successfully carried out ocean research campaigns in Korean jurisdictional and adjacent waters, including continental margins and coastal zones within the Korean Exclusive Economic Zone (EEZ), for 29 years. However, it will soon be reaching the end of its useful service life. A replacement for R/V EARDO is urgently needed to ensure the safety of vessel itself and its crews, and efficient ship operation and maintenance, as well as to meet modern scientific mission requirements (SMRs). Basic specifications for a replacement ship have been devised and reviewed over the past nine months. A test of the proposed hull form was also performed. The total tonnage of the proposed vessel is approximately 740 tons, and the overall length and width are 62.0 and 11.6 m, respectively. The new ship will thus be 73% larger than the current R/V EARDO; in particular, the research workspace will be 4.4 times larger. The major design priorities are the propulsion system, efficiency of radiated noise and vibration control, and the dynamic positioning system. An environmentally friendly emission system, meeting International Maritime Organization (IMO) Tier III regulations, will be installed in the third exhaust pipe. Various wet and dry lab spaces as well as 32 different scientific instruments have also been considered in the ship design.

• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.3
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• pp.39-49
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• 2020

Rice paddy cultivation is one of the major sources in methane (CH₄) emission of which accurate assessment would be a prerequisite for agricultural greenhouse gas management. Biomass treatment in paddy fields is an important factor that affects CH₄ emissions and thus needs to be taken into account. The objectives of this study were to apply drone images to investigate organic matter practices and to incorporate into the estimation of CH₄ emissions from paddy fields. Three study areas were selected by one from each of the three different regions of Yeongnam, Honam and Jungbu, which are the most active region in paddy cultivation. The eBee drone was used to take images of the study sites twice a year; Jul mid-season for identifying rice cultivation area; Jan for investigating rice straw management and winter crop cultivation. Based on biomass management practices, different emissions factors were assigned on an individual paddy field and CH₄ emmisions were estimated by multiplying respective areas. The ratios of rice straw application and winter crop cultivation were 1.4% and 37.2% in Hapcheon, 1.3% and 19.8% in Gimje, and 0.0% and 0.5% in Dangjin, respectively. The CH₄ emissions estimates for respective sites were 0.40 ton CH₄/year/ha, 0.34 ton CH₄/year/ha, and 0.29 ton CH₄/year/ha. On average, estimated CH₄ emissions of this study were 28.5% less than the current Tier 2 CH₄ emission estimation method.