• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.1
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• pp.13-19
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• 2015

Among the various possible factors affecting the Minority Carrier Life Time (MCLT) of the mc-Si crystal, dislocations formed during the cooling period after solidification were found to be a major element. It was confirmed that other defects such as grain boundary or twin boundary were not determinative defects affecting the MCLT because most of these defects seemed to be formed during the solidification period. With a measurement of total thickness variation (TTV) and bow of the silicon wafers, it was found that residual stress remaining in the mc-Si crystal might be another major factor affecting the MCLT. Thus, it is expected that better quality of mc-Si can be grown when the cooling process right after solidification is carried out as slow as possible.

• Journal of the Korean Society of Safety
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• v.12 no.2
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• pp.57-64
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• 1997

Fatigue crack propagation behaviors and life prediction for SUS 321 plate and its electron beam weld metal were investigated using compact tension specimens. The larger the stress ratio is, the faster the crack propagates, but the variation of crack propagation rate decreases. The effect of stress ratio is greater in the slow crack propagation area than in the faster one. The crack propagation rate of electron beam weld metal is faster than that of base metal because of hardening, weld defect and residual stress in welding area. The crack propagation rate of transverse weld metal has a lower than that of base metal due to the effect of residual stress, but in the time of passing through welding area, has a higher rate. The crack propagation rate using $\Delta$K$_{eff}$ can be well plotted regardless of stress ratio. The fatigue life prediction method of considering crack closure more exactly predicts fatigue life than conventional one. conventional one.e.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.108-113
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• 1997

A field experiment was conducted to evaluate effect of phosphate coated slow release fertilizer on the directly seeded rice. Odae byeo was seeded by drill under dry condition. The soil was a sandy clay loam soil located in the Experimental Farm of the Kangweon National University, Chuncheon, Kangweon-Do. The yield of rice from the urea applicated directly seeded field was 84.9% of the yield from the transplanted field, and showed no difference between split application treatments. The yield from the phosphate coated slow release fertilizer was the highest showing 110.7% of the yield from the urea application. The yield from the polymer coated slow release fertilizer was 90.4%. The yield from the organic fertilizer 400kg/10a treatment was 81.8% and was 94.8% from the organic fertilizer 600kg/10a treatment. In 1996 experiment, the yield from the phosphate coated slow release fertilizer was higher than the yield from the transplanted field. The $NO_3-N$ and $NH_4-N$ concentrations in soil solution at the depth of 15cm revealed that nitrogen leaching was the highest from the urea N40-0-30-30 treatment, and the lowest from the phosphate coated slow release fertilizer. The phosphorus concentration showed similar pattern. Therefore, use of phosphate coated slow release fertilizer increased rice yield and decreased loss of nitrogen and phosphorus loss.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.228-232
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• 2007

Slow-release fertilizers (SRF) have been used to reduce nutrient loss through increasing fertilizer efficiency and to save labor. Several SRFs were developed for rice plant in Korea, but there is few for horticultural crop plants. Two slow-release complex fertilizers, 100T and 150T, which made for controlling nitrogen release time up to 100 and 150 days, respectively, were selected for the incubation test cto evaluate nitrogen (N) release rate in soil. The N of urea selected as the control was completely released within a week after application. Sixty three and 53% of total N were released from 110T and 150T of slow release fertilizers within 8th weeks after application, respectively. For pepper cultivation CF110 and CF150, new slow-release complex fertilizer, were made of mixing 40% of conventional fertilizer and 60% of 110T and 150T, respectively, based on the amount of recommended fertilizer for pepper cultivation $(N-P_2O_5-K_2O=190-112-149\;kg\;ha^{-1})$, and were totally applied before pepper transplanting in the field as the basal fertilizer. Inorganic N $(NH_4^+-N+NO_3^--N)$ concentration in soil was higher in the CF110 treatment than in the control (NPK) at all period of pepper cultivation. In the CF150 treatment concentration of inorganic N in soil was low compared to control up to 8th weeks after transplanting. However, there was no difference in plant height and nutrient content of pepper leave between CF110 treatment and the control. In comparison, plant height was significantly lower in CF150 than the control and CF110 treatments. Around 4% of fresh pepper yield was increased in CF110 compared to the control, but it was decreased to about 2% by CF150 treatment. Conclusively, CF110 form could be recommended as a slow release fertilizer for pepper cultivation.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.351-356
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• 2010

Brachypodium distachyon is rapidly emerged in biological study and has been currently used as a model system for genetics and functional studies for crop improvement and biofuel production. Phosphinothricin (PPT) has been widely used as a selectable agent, which raises ammonium content and induces toxicity in non-transformed plant cells. However PPT selection is not much effective on Brachypodium callus consequently reducing transformation efficiency. In order to identify the efficient conditions of PPT selection, calli obtained from mature seeds of Brachypodium (PI 254867) were cultured on the callus inducing medium (CIM) or regeneration medium (ReM) containing serial dilutions of the PPT (0, 2, 5, 10, and 15 mg/l) in dark or light condition. Callus growth and ammonium content of each treatment were measured 2 weeks after the treatment. Although callus growth and ammonium content did not show much difference in CIM, slow callus growth and increased ammonium accumulation were found in ReM. No significant difference of ammonium accumulation in response to PPT was found between dark and light conditions. In order to identify major factors affecting increased ammonium accumulation, callus was cultured on the media in combined with phytohormones (2,4-D or kinetin) and carbon sources (sucrose or maltose) containing with PPT (5 mg/l). The highest ammonium content in callus was found in the kinetin and maltose media.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.sup1
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• pp.30-37
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• 2008

The knowledge of motility disorders of the gastrointestinal tract has increased over the past decades. The development of newer therapies for bowel motility disorders has been disappointingly slow. Prokinetic agents are medications that enhance coordinated gastrointestinal motility and transit of material in the gastrointestinal tract. These agents are pharmacologically and chemically diverse. However, life-threatening adverse effects of prokinetic agents such as cisapride was present. In this review, pharmacologic effects and use of prokinetic agents in children was introduced.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1868-1872
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• 2010

The LED illuminator has merits that it has low power consumption, long life and emits low Co2 gas. As it has many merits in comparison with existing illuminator it is a realistic alternative. but its possession in illuminator market shows slow increasement unexpectedly. Because its price is very high only low power consumption can not keep pace with economical efficiency. In this paper I analyzed economical efficiency about LED illuminator when it is applied at subway station.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.4
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• pp.267-291
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• 2010

Life can be kept in suspended animation either before fertilization at oocyte stage or after fertilization at different stages of embryonic development for a variety of reasons. It not only has potential applications in fertility preservation and management in human but also has important roles in the preservation and management of animal genetic resources, low-cost international movement of selected genetics, and rapid dissemination of germplasm through assisted reproductive technologies (ART) and genetic engineering. Currently, slow-freezing and vitrification are the two approaches by which oocytes and embryos can be cryopreserved for long-term storage. Both of these methods have their own advantages and disadvantages but allow the cryopreservation of oocytes and embryos with comparable efficiency. Vitrification of oocyte and embryos, although proven successful just 13 years after slow-freezing, is generally considered an emerging technology and appears to slow gain acceptance in both animal and human ART despite having controversial storage and contamination issues. In this manuscript, we discuss the basic techniques of oocyt/embryo cryopreservation and review the current status and recent developments in vitrification.

• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.823-829
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• 2017

To increase the shelf-life of strawberry, samples were treated with two gel packs containing slow-released chlorine dioxide ($ClO_2$) gas at 3~5 ppm for 6 days at room temperature and the changes in the major chemical components (ascorbic acid, polyphenols, flavonoids and anthocyanin) contents and antioxidative activities (DPPH, ABTS radical scavenging and metal chelating activity) were investigated. The content of ascorbic acid of control was 40.38 mg% and contained 35.67~44.75 mg% during 6 days. There was no tendency to increase or decrease during storage period. The contents of ascorbic acid of control and 3~5 ppm $ClO_2$ gas treated samples were not significantly different during storage period. The content of polyphenol compounds of initial stage was 111.23 mg% and contained 117.78~132.40 mg% during 6 days. The contents of polyphenol compounds of 3~5 ppm $ClO_2$ gas treated samples were 103.51~130.25 mg%. There were no significant different between them during storage. The flavonoids and anthocyanin contents were not different from the control during storage period regardless of 3~5 ppm $ClO_2$ gas treatment. Furthermore, antioxidative activities were not different among the control and $ClO_2$ gas treatments during storage.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.294-303
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• 2019

To extend the shelf-life of chicken breast meat, samples were treated with gel-packs containing slow-released $ClO_2$ gas at 7-15 ppm for 8 days at $4^{\circ}C$. And the changes in lipid oxidation and taste compounds of the samples were investigated. TBARS value of the chicken breast was slightly increased during storage. TBARS value of gas treatments was similar to the control during storage. There were 14 fatty acids in the chicken breast. And there was no change in the fatty acid composition during storage, and there was no significant difference between the control and gas treatments. The content of free amino acids was gradually increased during storage. The content of free amino acids were not significantly different between the control and gas treatments during storage. The content of GMP in the control and gas treatments were decreased during storage. However, gas treatments showed slightly higher content than that of control. AMP was not significantly different between the control and gas treatments. IMP gradually decreased during storage and the content of inosine and hypoxanthine was increased. IMP, inosine and hypoxanthine contents of gas treatment were similar to control, but the control tended to change more rapidly than those of gas treatments.