• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.237-243
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• 2001

The experiment was conducted to investigate the effect of different mulching materials on the growth and quality of oriental melon in protected cultivation. Soil temperature, plant growth and fruit quality were affected by different mulching materials, clear polyethylene (P.E.) film (control), clear inset between black P.E. film, green P.E. film. and recycled ethylene vinyl acetate (E.V.A.) film. The highest night soil temperature was at 20 cm depth under green P.E. film, but was at 5 cm depth under other materials. Difference of soil temperature as affected by mulching materials decreased with increasing soil depth. Plant height, number of nodes, leaf area index (LAI), crop growth rate (CGR), and relative growth rate (RGR) at 30 days after transplanting were significantly greater in the recycled E.V.A. film treatment than in the other treatments. Fresh weight of weeds growth under the mulching materials was not affected by mulching material at 30 days after transplanting. However, it was the greatest under clear P.E. film mulching at 90 days after transplanting. Harvesting time of recycled E.V.A. film was 2 days earlier than that of clear P.E. film. Difference in fruit weight and length, and soluble solid content were not affected by the mulching materials. Marketable yield was 2,426 kg.10a$^{-1}$ in recycled E.V.A. film treatment, which was 6% greater than in clear P.E. film treatment.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.3-9
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• 1999

The recent technical trend in hot rolling of steel can be described as process and product technologies which have been progressed with modern mill equipment and computers. Precise gauge and width control can be achieved by up-to-date control methods such as AGC and AWC systems. Roll benders and various shape control systems enabled high quality flatness and crown control. Mills can produce higher tensile materials by new process based on process metallurgy. The use of high speed steel rolls and on line roll grinders make the schedule free rolling easier which results in cost saving. Process itself goes toward continuous and simple flow type which has lower operation. Endless rolling and strip casting are examples of the trend. Materials with higher tensile strength and various functions have been developed in last years to meet the customer's needs and this trend will continue.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.652-655
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• 2004

In these days, repair materials for leakage cannot help but being taken in temporary way without any noticeable countermeasure. This kind of repair is socially criticized many times that is defective construction even if tills costs a lot. It was not arrange the standard for performance evaluation test method and quality maintenance for materials, even it has been used various injection repairing agent. In conclusion, We suggest that the test method for repair materials for leakage to establish the leakage repairing technology as increase of structure demand, so that the necessity of the establishment of the quality control standard and the performance testing way on the relevant water-proof seal is increasing a lot to regulate the water-proof technology and the leakage repair technology.

• Journal of the Korean Society of Radiology
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• v.2 no.4
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• pp.11-25
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• 2008

As breast cancer shows the highest incidence among women's cancers, the use of mammography is also increasing as a screening test. Mammography should produce high-quality images for accurate diagnosis. For this, it is necessary to manage the performance and image quality of mammography. Thus, in order to investigate quality control, the present study conducted a questionnaire survey of 37 hospitals registered as breast cancer medical examination centers in Gwang-Ju, concerning their quality control of mammography. In the results of surveying the characteristics of apparatus use for mammography, many respondents did not know about the equipment that they were using. Of the hospitals, 19 (49%) were using film, 19 (49%) CR, and 1 DR. In the results of asking how to do quality control, only 38% answered that they inspected according to the manual. In addition, all the surveyed hospitals had specialized agencies do quality control for them. As to the reason for using agencies, 65% mentioned limitations in personnel, time, distance, etc, and 44% mentioned the absence of machines and materials. These results suggest that quality control is being performed perfunctorily, as well as passively and indifferently as it relies on specialized agencies. Accordingly, it is necessary to provide regular education for enhancing people's perception of quality control and to perform quality control adequately in the presence of Radiologist.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.6
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• pp.522-527
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• 2019

In order to fabricate high-quality SiC substrates for power electronic devices, various single crystal growing methods were prepared. These include the physical vapor transport (PVT) and top seeded solution growth (TSSG) methods. All the suggested SiC growth methods generally use induction-heating furnaces. The temperature distribution in this system can be easily adjusted by changing the hot-zone design. Moreover, precise temperature control in the induction-heating furnace is favorably required to grow a high-quality crystal. Therefore, in this study, we analyzed the heat transfer in these furnaces to grow SiC crystals. As the growth temperature of SiC crystals is very high, we evaluated the effect of radiation heat transfer on the temperature distribution in induction-heating furnaces. Based on our simulation results, a heat transfer strategy that controls the radiation heat transfer was suggested to obtain the optimal temperature distribution in the PVT and TSSG methods.

• Proceedings of the Korean Vacuum Society Conference
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• 2007.02a
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• pp.39-39
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• 2007

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.367-372
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• 2002

The waterproofing systems of concrete bridge deck are installed under the complex circumstances, such as traffic loading, weather, and the condition of the deck concrete. For assuring the effectiveness of waterproofing system, the materials and the construction method and timing ought to be suitably selected with the procedures of waterproofing and the system has to ensure the economical performances. First of all, we discussed whether the quality and performance criteria for highway bridge deck are resonable or not through the investigation of domestic and foreign criteria. The basic properties of waterproofing membranes on market and the performance of waterproofing systems of concrete bridge deck have also been investigated in the view of the damages frequently reported from job site. In this way, the causes and measures of damages, the guidelines of design, construction, quality control, and maintenance, the test methods and criteria of membranes and waterproofing system, are proposed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.5
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• pp.60-66
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• 2000

Coating immobilization is the process by which the wet coating applied to paper or paperboard reaches the final form. A coating immobilization point is defined as the solids content reached during drying where no further redistribution of coating materials occurs. Good control of coating immobilization is important in producing coated paper and paperboard with consistent high quality. This paper discusses the technical concepts of how coatings immobilize, and describes the importance of good immobilization control on coating holdout and coating structure. The use of soy protein polymers to modify the coating immobilization point is discussed. Soy proteins, because of their interaction with coating pigments, make a significant contribution to the immobilization characteristics of coastings. This technology gives the formulator options for changing the immobilization point to improve the performance of the coating. The importance of immobilization on casting uniformity, microporosity and sheet qualities is discussed, including binder migration, mottle, gluing, and print quality.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.730-736
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• 2013

This study was to establish irradiation process for serving ginseng chicken porridge to immune-compromised patients. Raw chicken, glutinous rice, ginseng, garlic, dried jujube and carrot were used as raw materials for ginseng chicken porridge. The initial level of microorganisms contaminated in raw materials and their predominant species were determined. The level of microorganism detected in raw chicken and in ginseng were 3.4 Log CFU/g and 4.7 Log CFU/g, respectively. Major predominant microorganisms were Pseudomonas fragi in chicken, Enterobactor faecalis in carrot, and Bacillus subtilis in other materials. Chicken and carrot were excluded from irradiation treatment because ordinary thermal treatment can inactivate the microorganisms contaminated in those materials. Five kGy of gamma ray was the effective sterilizing dose required to inactivate B. subtilis in glutinous rice, garlic and jujube, and 10 kGy in ginseng. Ginseng chicken porridge was prepared with each of raw materials gamma-irradiated with the selected sterilizing doses. Control was ginseng chicken porridge prepared with non-irradiated materials. The growth of microorganisms was not observed in the chicken porridge prepared with irradiated raw materials. Sensory results showed that the score of flavor and off-flavor was slightly lower in ginseng chicken porridge prepared with irradiated raw materials than in control. This was considered to be due to the increase of TBARS values by gamma irradiation. However, there was no significant difference on overall acceptance between the porridge prepared with irradiated raw materials and control. The results showed that the individual gamma irradiation of raw materials can be applied to prepare ginseng chicken porridge as meals for the immunocompromised patients.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.127-128
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• 2023

Recently, OSC (off-site construction) construction has been revitalized as a response to the decline in building quality and productivity due to lack of skilled manpower at construction sites, and PC (precast concrete) construction, a representative OSC construction, is insufficiently applied to public housing.This is the situation.In addition, in the case of general contents appearing in standard specifications, the construction standards for quality assurance remain in the 1990s and do not correspond to the current construction environment.In order to improve the quality of PC member joints, we compared and analyzed Korean and Japanese specifications to establish appropriate standards for PC construction quality control, focusing on the quality of grout used in joints.