• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.2
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• pp.109-117
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• 2017

Due to the rise of customer's alertness about fresh foods to health, in the past few years, the consumption of fresh food has increased sturdily. The use of gas scavengers is the most appropriate packaging technologies for fresh, fresh-cut produces and in ready to eat products. The gas absorber/scavenger has ability to protect or stabilize the wanted properties and shelf life of food. The success of gas absorbers in food depends on many parameters such as types of foods, storage temperature, relative humidity, initial gas concentration, and the characteristics of package materials. In this review article, we focus on the most recent research trends in gas scavenging systems used in food packaging, future trends. Intense research from industry and engineers remains important to the development of gas scavenging package that fulfill consumer requirements, enhance product quality, and offer environmentally friendly design and cost-effective application.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.1974-1982
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• 2020

Numerical prediction of fission product plateout and circulating coolant activities under normal operating conditions is crucial in the design of a high temperature gas-cooled reactor (HTGR). The results are used for the maintenance and repair of the components as well as the safety analysis regarding early source terms under loss of coolant accident scenarios. In this work, a new computer code named POSCA (Plate-Out Surface and Circulating Activities) was developed based on a one-dimensional model to evaluate fission product plateout and circulating coolant activities within the primary circuit of a HTGR. The verification and validation of study for the POSCA code was done using available analytical results and two in-pile experiments (i.e., OGL-1 and VAMPYR-1). The results of the POSCA calculations show that POSCA is able to simulate plateout and circulating coolant activities in a HTGR with fast computation and reasonable accuracy.

• Journal of Korea Game Society
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• v.2 no.2
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• pp.60-65
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• 2002

In the majority of today's computer games, the behaviour of characters are controlled by pre-defined game logic or pre-generated motion. As game developers strive for richer and more interactive games, they often encounter limitations with this approach. This paper attempts to construct a game model using Genetic Algorithms (GAs) in order to produce more intelligent and compelling computer games. Based on teaming ability, the use of GAs will enable the characters to continually evolve, providing a changing and dynamic game environment. A real-time game was implemented to investigate the performance and limitations of the system.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.223-228
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• 2012

The low-temperature pyrolysis of ABS, polyethylene (PE) and an ABS-polyethylene (ABS-PE) mixture was conducted in a batch reactor at $450^{\circ}C$. The conversion and the product yield were measured as a function of the reaction time with a variation of the mixture composition. The oil products formed during pyrolysis were classified into gas, gasoline, kerosene, gas oil and heavy oil according to the petroleum product quality standard of the Ministry of Knowledge Economy. The pyrolysis conversion increases with an increase in the content of PE. The yield of the pyrolytic products was ranked as heavy oil>gas>gasoline>gas oil>kerosene as the content of PE in the mixture increases.

• Journal of the Korean Institute of Gas
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• v.25 no.1
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• pp.7-13
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• 2021

The re-liquefaction drum is a product that installed spray nozzles at the top to directly spray overcooled LNG into evaporative gas and installed demistors to facilitate gas separation, which was developed to increase the re-liquidity efficiency of small scale re-liquefaction facilities. In the hydrostatic test of the drum, no leakage occurred even at a pressure of 1.5 times the design pressure, but during the BOR(Boil Off Rate) test, the bolt loosening occurred due to contraction and expansion by temperature change. For the continued use of the product, insulation construction on flange connections was developed to enable detachment and attachment, and the comparison of heat load with existing insulation confirmed that it was very small compared to the inlet flow rate in the drum.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1571-1576
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• 2014

Nutritive values of green and black tea by-products and anti-nutritive activity of their tannins were evaluated in an in vitro rumen fermentation using various molecular weights of polyethylene glycols (PEG), polyvinyl pyrrolidone (PVP) and polyvinyl polypyrrolidone as tannin-binding agents. Significant improvement in gas production by addition of PEG4000, 6000 and 20000 and PVP was observed only from black tea by-product, but not from green tea by-product. All tannin binding agents increased $NH_3$-N concentration from both green and black tea by-products in the fermentation medium, and the PEG6000 and 20000 showed relatively higher improvement in the $NH_3$-N concentration. The PEG6000 and 20000 also improved in vitro organic matter digestibility and metabolizable energy contents of both tea by-products. It was concluded that high molecular PEG would be suitable to assess the suppressive activity of tannins in tea by-products by in vitro fermentation. Higher responses to gas production and $NH_3$-N concentration from black tea by-product than green tea by-product due to PEG indicate that tannins in black tea by-product could suppress rumen fermentation more strongly than that in green tea by-product.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.553-556
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• 2005

Pyrolysis of polyethylene was carried out in the stainless steel reactor of internal volume of $40cm^3$. Pyrolysis reactions were performed at temperature $390-450^{\circ}C$ and the pyrolysis product were collected separately as reaction products and gas products. The molecular weight distributions(MWDs) of each liquid product were determined by GC-SIMDIS. Molecular weight of each product were decreased wi th increase of react ion temperature and time.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.937-945
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• 2014

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at $10^{\circ}C$. The GTS stored at $20^{\circ}C$ and $30^{\circ}C$ showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on $NH_3$-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and $NH_3$-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and $NH_3$-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin's activity in the rumen.

• Journal of the Korean Institute of Gas
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• v.7 no.4 s.21
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• pp.1-6
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• 2003

Freon gas has been replaced with LPG in the cosmetic industry because of its bad effects on environment. In this paper, skincare product with a cooling effect was developed using LPG as propellant. A cooling effect is obtained by the ice which is formed through spraying. Ice formation is affected by the composition of LPG and most of all, the high content of propane gas in the LPG results in the irregular surface of ice formed because of its high vapor pressure. Also the ratio of LPG to skincare solution affects the formation of ice.

• Journal of Hydrogen and New Energy
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• v.33 no.6
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• pp.636-642
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• 2022

The "Hydrogen Economic Activation Road map" was announced in 2019, and hydrogen demand is expected to exceed 470,000 tons per year in 2022 and keep increasing. Under this circumstance, it has become important to understand the greenhouse gas (GHG) emissions associated with various hydrogen production pathways. In this study, the evaluation of life cycle GHG emissions regarding the hydrogen produced as by-product from coke oven gas (COG) in steel mill is conducted. To cover the possible range of operations, three literatures were reviewed and their data of inputs and outputs for the process were adopted for calculation. Life cycle inventories and emission factors were mostly referred to GaBi and Intergovernmental Panel on Climate Change (IPCC) guidelines, respectively. When there are multiple products from a single process, the energy allocation method was applied. Based on these sources and the assumptions, the life cycle emission values of COG-based hydrogen were found to be 3.8 to 4.7 kg/CO₂-eq./kg-H₂.