• Transactions of Materials Processing
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• v.14 no.5 s.77
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• pp.452-459
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• 2005

Gas assisted injection molding (GAIM) is an innovative low-pressure injection molding technique that can provide numerous benefits such as reduced part warpage, excellent surface quality without sink marks, low injection pressure and greater design flexibility. However, adoptions of GAIM may cause unexpected defects since it requires many subtle design factors such as resin shot size, delay time and gas injection pressure, which wouldn't be considered in conventional injection molding process. Therefore, experiences applying GAIM should be collected and examined in order to establish design rules of the new technique. The purpose of this paper is to summarize developing cases of three automotive interior parts such as instrument panel, map pocket folding and center facia side panel so that possibilities and limitations of GAIM were examined. As a result, it is necessary to consider characteristics of GAIM at the initial stage of part design in order to obtain various advantages of the GAIM process without occurring severe defects, which would increase time and cost required to the part development.

• Journal of the Korean Ceramic Society
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• v.34 no.3
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• pp.249-256
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• 1997

The effect of process parameter of plasma assisted chemical vapor deposition (PACVD) on the variation of the ratio between cubic boron nitride (c-BN) and hexagonal boron nitride (h-BN) in the film was in-vestigated. The plasma was generated by electric power with the frequency between 100 and 500 KHz. BCl3 and NH3 were used as a boron and nitrogen source respectively and Ar and hydrogen were added as a car-rier gas. Films were composed of h-BN and c-BN and its ratio varied with the magnitude of process parameters, voltage of the electric power, substrate bias voltage, reaction pressure, gas composition, sub-strate temperature. TEM observation showed that h-BN phase was amorphous while crystalline c-BN par-ticle was imbedded in h-BN matrix in the case of c-BN and h-BN mixed film.

• The KSFM Journal of Fluid Machinery
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• v.19 no.3
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• pp.19-24
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• 2016

Oil sands are a mixture of sand, clay, and a high-viscosity petroleum called bitumen. Steam-Assisted Gravity Drainage (SAGD) is the most viable and environmentally safe recovery technology for extracting bitumen. It extracts the viscosity-lowered bitumen by high pressure, high temperature steam injected into the bitumen reservoir. The steam is produced at the Central Processing Facility (CPF). Typically, more than 90% of the energy consumed in producing bitumen are used to generate the steam. Fuels are employed in the process, which cause economic and environmental problems. This paper explores the retrofit of heat exchanger network to reduce the usage of hot and cold utilities. The hot and cold utilities are reduced respectively 6% and 37.3% which in turn resulted in 5.3% saving of total annual cost by improving the existing heat exchanger network of the CPF.

• The korean journal of orthodontics
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• v.46 no.1
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• pp.55-61
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• 2016

Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required.

• Journal of Families and Better Life
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• v.20 no.2
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• pp.83-95
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• 2002

The objectives of this study were 1) to analyze the attitudes about Elderly Assisted Living(EAL), 2) to consider the policy implications for elderly communal housing according to socio-economic status(income, occupation and education). The survey was undertaken from August to September, 2000 in Seoul and Kyunggi-Do(Ilsan, Bundang). The data were analyzed by SPSS Window program. The major findings were as follows: Most of the respondents prefered to live in EAL(over 56%), under 10 units and desired to be serviced(housework.leisure medical program.meal service). The upper class respondents preferred high-rise apartment style inner city or suburban and prefered paid services in EAL. They would willingly to pay over 800,000 won for living expenses and more than 200 million won for buying their own EAL. The middle class respondents prefered 5 stories multi-family house style with common facilities as a number. And they prefered to common facilities opening to public if the quality of facilities were better. The low class respondents prefered 5 stories multi-family house style and prefered to live within 30 minutes apart from their families and friends. They would pay under 300,000~600,000won for monthly living expenses and under 100 million won for their own EAL.

• KSBB Journal
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• v.23 no.5
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• pp.362-368
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• 2008

High Hydrostatic Pressure assisted (HHP) process enhancement for food and allied industries are reported in this paper review. Recently, considerable research has been devoted to the improvement of mild thermal processing techniques and to the development of alternative mild processing technologies. HHP assisted can enhance existing extraction, processes and enable new commercial extraction opportunities and processes. New HHP processing approaches have been proposed, including, the potential for modification of plant cell material to provide improved bioavailability of micro nutrients while retaining the natural-like quality, simultaneous extraction. Therefore, High Hydrostatic Pressure assisted (HHP) technologies could have a strong presence in the future of the biotechnology industry.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.109-127
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• 2014

Maize is one of the most important food and feed crops in the world including Southeast Asia. In spite of numberous efforts with conventional breeding, the maize productions remain low and the loss of yields by drought and downy mildew are still severe in Asia. Genetic improvement of maize has been performed with molecular marker and genetic engineering. Because maize is one of the most widely studied crop for its own genome and has tremendous diversity and variant, maize is considered as a forefront crop in development and estimation of molecular markers for agricultural useful trait in genetics and breeding. Using QTL (Quantitative Trait Loci) and MAS (Marker Assisted Breeding), molecular breeders are able to accelerate the development of drought tolerance or downy mildew resistance maize genotype. The present paper overviews QTL/MAS approaches towards improvement of maize production against drought and downy mildew. We also discuss here the trends and importance of molecular marker and mapping population in maize breeding.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.3
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• pp.570-575
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• 2002

It is well-known that the bond strength between CFRP(Carbon Fiber Reinforced Plastic) and aluminum is significantly affected by the surface treatment of the CFRP and the aluminum. This study investigates the surface treatment of CFRP to improve the T-peel strength of CFRP/aluminum composites. The surface of %CFRP([0^0]_{14})$ was treated by the ion assisted reaction method under oxygen environment. T-peel strength tests were performed based on the procedure of ASTM D1876-95. The T-peel strength of surface-treated CFRP/aluminum composites was compared with that of untreated CFRP/aluminum composites. The results showed that the T-peel strength of surface-treated CFRP/aluminum composites was about 5.5 times higher than that of untreated CFRP/aluminum composites. SEM examination showed that the improvement of T-peel strength was attributed to the uniform spread and fracture of epoxy adhesive.

• Journal of Biosystems Engineering
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• v.34 no.5
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• pp.371-376
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• 2009

Microwave digestion is a preferred pretreatment method for agricultural samples because of its quick chemical reaction and minimum loss of analytes. In this research, a feedback temperature controller was developed to control the temperature inside a vessel for the microwave-assisted digestion system. An existing industrial microwave oven was fitted with the temperature controller for controlling inside temperature of the vessel. Four control methods, On/Off, proportional (P), proportional integral (PI), and proportional integral derivative (PID) were used and compared. Experimental results showed that PID control produced best temperature control performance. The PID controller could maintain the temperature of water sample and rice sample in the digestion system with error range of $-2.5{\sim}3.3^{\circ}C$ and $-1.9{\sim}0.5^{\circ}C$ at set temperature of $170^{\circ}C$, respectively.

• Mass Spectrometry Letters
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• v.3 no.2
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• pp.47-49
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• 2012

Myoglobin was hydrolyzed by microwave-assisted weak acid hydrolysis with 2% formic acid at $37^{\circ}C$, $50^{\circ}C$, and $100^{\circ}C$ for 1 h. The most effective hydrolysis was observed at $100^{\circ}C$. Hydrolysis products were investigated using matrixassisted laser desorption/ionization time-of-flight mass spectrometry. Most cleavages predominantly occurred at the C-termini of aspartyl residues. For comparison, weak acid hydrolysis was also performed in boiling water for 20, 40, 60, and 120 min. A 60- min weak acid hydrolysis in boiling water yielded similar results as a 60-min microwave-assisted weak acid hydrolysis at $100^{\circ}C$. These results strongly suggest that microwave irradiation has no notable enhancement effect on acid hydrolysis of proteins and that temperature is the major factor that determines the effectiveness of weak acid hydrolysis.