• Journal of the Korean Solar Energy Society
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• v.32 no.4
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• pp.51-58
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• 2012

This study aims to analyze characteristics of Cell surface temperature and generated power performance for improving PV(Photovoltaic) system condition according to the cell opening ratio of transparent crystal PV system at Spandrel of curtain-wall. For this purpose, alternatives were classified for eight different cases that opening ratio of transparent crystal PV system varied from 0% to 70%, which was used by simulation tool, EnergyPlus. As results, it turned out that increasing opening ratio of transparent crystal PV system led higher PV surface temperature, back-sheet type was thus the most advantageous for decreasing surface temperature, annual generating efficiency, and annual accumulated generating power. Consequently, blocking off air space from outside insolation can advantageously keep to be better condition for generated power performance.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.283-288
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• 2006

Characteristics of the rootstock formation and flower bud differentiation according to sowing time for production of the high quality rootstock in Chicory (Cichorium intybus L.) was investigated. The flower bud initiation was on the 17th of July after sowing in April, the 2nd of July after sowing in May, the 30th of July after sowing in June and the 1st of October after sowing in July. But they didn't differentiate after sowing in August and September. The days required from germination to flower bud initiation and accumulated temperature depended on the weather. If the outside air temperature was high, the days required were less, If the outside air temperature was low, the days required were greater, the accumulated temperature was similar to the days required in this experement, too. The rootstock sown from April to July wasn't good enough to be use because the flower bud differentiation was generated before harvestable weight. the weight of rootstock was sown in September wasn't heavy enough in weight because the outside air temperature was too low for it to grow well. The plant grows slow and steady through out winter. The rootstock sown in August was havestable 200g in 90 days after sowing before the flower bud differentiated. The best sowing time for the production of high quality rootstock of Chico in the climate of Korea is researched to be August.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.127-136
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• 2019

Sweet sorghum (Sorghum bicolor L. Moench), compared to traditional crops, has been evaluated as a useful crop with high adaptability to the environment and various uses, but cultivation has not expanded owing to a lack of related research and information in Korea. This study was conducted to estimate heading date in 'Chorong' sweet sorghum based on climate data of the last 30 years (1989 - 2018) from six regions (Jeonju, Buan, Jeongup, Imsil, Namwon, and Jangsu) in Jellabuk Province. In addition, we compared the growth and quality factors by sowing date (April 10, April 25, May 10, May 25, June 10, June 25, and July 10) in 2018. Days from sowing to heading (DSH) increased to 107, 96, 83, 70, 59, 64, and 65 days in order of the sowing dates, respectively, and the average was 77.7 days. The effective accumulated temperature for heading date was $1,120.3^{\circ}C$. The mean annual temperature was the highest in Jeonju, followed in descending order by Jeongup, Buan, Namwon, Imsil, and Jangsu. The DSH based on effective accumulated temperature gradually decreased in all sowing date treatments in the six regions during the last 30 years. DSH of the six regions showed a negative relationship with mean temperature (sowing date to heading date) and predicted DSH ($R^2=0.9987**$) calculated by mean temperature was explained with a probability of 89% of observed DSH in 2017 and 2018. At harvest, fresh stem weight and soluble solids content were higher in the April and July sowings, but sugar content was higher in the May 10 ($3.4Mg{\cdot}ha^{-1}$) and May 25 ($3.1Mg{\cdot}ha^{-1}$) sowings. Overall, the April and July sowings were of low quality and yield, and there is a risk of frost damage; thus, we found May sowings to be the most effective. Additionally, sowing dates must be considered in terms of proper harvest stage, harvesting target (juice or grain), cultivation altitude, and microclimate.

• Journal of ILASS-Korea
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• v.23 no.3
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• pp.128-135
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• 2018

In this study, the following conclusions could be obtained from the analysis of emissions contribution rates and features for contaminated emissions by 13,456 gasoline vehicles passed in the vehicle load test (ASM-idle) under the inspection year 2013 to 2017. It was confirmed that the contamination of the CO, HC, NOx by the displacement is reduced on over 3L engine. As a result of comparing the exhaust gas in the low speed idle mode and the AS2525 mode, the exhaust gas in the low speed idle mode was measured high. It is estimated that if ISG function is applied, emissions from idle condition will be reduced. NOx emissions were reduced when the engine power was above 200HP. It has been confirmed that the amount of exhaust emissions are significantly reduced for vehicles manufactured after 2004. As a result of analyzing the exhaust gas according to the season, it is judged that there is a correlation between HC and NOx according to the ambient temperature. The concentration of exhaust emission in vehicles with high accumulated distance increases, which is considered to be the result of aging of the vehicle.

• Journal of the Korean Society of Safety
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• v.27 no.4
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• pp.20-25
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• 2012

The purpose of this study is to analyze the thermal characteristics and to study fire hazard of electric leakage by iron power accumulated on circuit breaker in an iron processing factory. The thermal characteristics were analyzed while current was applied to the powder for ten minutes. Results showed that temperature of iron powder at 100 mA is $160^{\circ}C$ and at 175mA is $240^{\circ}C$. The sparks have occurred as iron powder drops between two(hot line and neutral line) wires and then iron powder explosion occurred while dropping continuously the iron powder on two lines. Those who work in the iron processing industry need to periodically remove and maintain the iron powder. The thermal characteristics in this paper can be used for electrical fire investigation and for basic data of thermal characteristic of leakage current through iron powder at iron processing factories.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.12-23
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• 2018

Quantitative information on biomass and available nutrients are essential for developing sustainable forest management strategies to regulate atmospheric carbon. An attempt was made at Chilapatta Reserve Forest in Duars region of West Bengal to quantify its above and below ground carbon along with available "N", "P" and "K" in the soil. Stratified random nested quadrats were marked for soil, biomass and litter sampling. Indirect or non-destructive procedures were employed for biomass estimation. The amount of these available nutrients and organic carbon quantified in soil indicates that the forest soil is high in organic carbon and available "K" and medium in phosphorus and nitrogen. The biomass, soil carbon and total carbon (soil C＋C in plant biomass) in the forest was 1,995.98, 75.83 and $973.65Mg\;ha^{-1}$. More than 90% of the carbon accumulated in the forest was contributed by the trees. The annual litter production of the forest was $5.37Mg\;ha^{-1}$. Carbon accumulation is intricately linked with site quality factors. The estimated biomass of $1,995.98Mg{\cdot}ha^{-1}$ clearly indicates this. The site quality factor i.e. tropical moist deciduous with optimum availability of soil nutrients, heavy precipitation, high mean monthly relative humidity and optimum temperature range supported luxuriant growth which was realized as higher biomass accumulation and hence higher carbon accumulated.

• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.31-36
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• 2008

This paper carried out a variety of analysis for a finding out the causes of fire on the street lamp. The glass bulb of 250W metal-halide(MH) lamps attached with the impurities rose the temperature by at $410.4^{\circ}$ in normal condition. Therefore, a lamp apparatus is needed the improvement for ventilation and the protection against dust. The heat of MH lamps is diffused through out the luminous tube, a glass bulb, and apparatus by degrees. The accident cause of the lamp is presumed that the accumulated heat by deposits of the inner part. It will be recommended the improvement of the structure that aren't the external impurity and accumulated heat in the MH lamps set.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.579-586
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• 2010

A genomic DNA fragment encoding a putative maltooligosyltrehalose synthase (NfMTS) for trehalose biosynthesis was cloned by the degenerate primer-PCR from cyanobacterium Nostoc flagelliforme. The ORF of NfMTS was 2,799 bp in length and encoded 933 amino acid residues constituting a 106.6 kDa protein. The deduced amino acid sequence of NfMTS contained 4 regions highly conserved for MTSs. By expression of NfMTS in E. coli, it was demonstrated that the recombinant protein catalyzed the conversion of maltohexaose to maltooligosyl trehalose. The $K_m$ of the recombinant enzyme for maltohexaose was 1.87 mM and the optimal temperature and pH of the recombinant enzyme was at $50^{\circ}C$ and 7.0, respectively. The expression of MTS of N. flagelliforme was upregulated, and both trehalose and sucrose contents increased significantly in N. flagelliforme during drought stress. However, trehalose accumulated in small quantities (about 0.36 mg/g DW), whereas sucrose accumulated in high quantities (about 0.90 mg/g DW), indicating both trehalose and sucrose were involved in dehydration stress response in N. flagelliforme and sucrose might act as a chemical chaperone rather than trehalose did during dehydration stress.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.8
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• pp.1-8
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• 2022

Inconel 718 is nickel-based and is increasingly being used as a key component in the nuclear, aerospace, and chemical industries which require high fatigue strength and oxidation, because of its excellent corrosion resistance, heat resistance, and wear resistance. It is a heat-resistant alloy which has excellent mechanical properties; however, material deformation, cracking, and shaking occur because of the high cutting temperature accumulated on the cutting surface during cutting processing, and heat accumulated at the insert boundary. Owing to these characteristics, various studies have been conducted, such as developing a tool exclusively for non-deletion, analyzing tool wear, and developing a tool cooling system. However, the optimization of the cutting process is still insufficient. In this study, the optimal process conditions were derived experimentally by cutting conditions according to the insert type during the cutting of Inconel 718.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.3
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• pp.141-146
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• 1988

This field experiment was carried out to determine the effects of fertilizer application time in spring on the growth, crude protein (CP) content and dry matter (DM) yield of gasses for grazing Application times of fertilizer were on March 10, March 20, March 30, April 9 and April 19, and control (non-fertilized) plot was involved. All fertilized plots were also treated with single and compound fertilizer. The first harvesting date for grazing was on April 30, and the regrowth soiling yield was investigated on June 9, 1988. In all fertilized plots, the growth, DM yield, CP, CP yield and nigrogen recovery of grasses were significantly increased compared with control, especially on the plot of March 30. The regrowth yield on March 30, April 9 and April 19 were shghtly hig!!a than those of the others. And there were not significant differences of grass growth, CP content, and DM yield between single-and compound fertilizer treatment. On March 30 which was the best time of fertilizer application in spring, the accumulated temperature was 116.6^{\circ}C.$ and the subsoil temperature at 10 cm depth was 8.1 - 8.6^{\circ}C.$. Considering the average meteorological condition in Suwon area, the optimum application time of spring fertilizer for grazing may be recommended on March 30-April 3 (accumulated temp.; 100-125^{\circ}C.$, subsoil temp.; 8-9^{\circ}C.$).