• New & Renewable Energy
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• v.20 no.1
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• pp.102-109
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• 2024

The Typical Meteorological Year (TMY) dataset compiles 12 months of data that best represent long-term climate patterns, focusing on global horizontal irradiance and other weather-related variables. However, the irradiance measured on the plane of the array (POA) shows certain distinct distribution characteristics compared with the irradiance in the TMY dataset, and this may introduce some biases. Our research recalculated POA irradiance using both the Isotropic and DIRINT models, generating an updated dataset that was tailored to POA characteristics. Our analysis showed a 28% change in the selection of typical meteorological months, an 8% increase in average irradiance, and a 40% reduction in the range of irradiance values, thus indicating a significant shift in irradiance distribution patterns. This research aims to inform stakeholders about accurate use of TMY datasets in potential decision-making. These findings underscore the necessity of creating a typical dataset by using the time series of POA irradiance, which represents the orientation in which PV panels will be deployed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.91-99
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• 2007

The research was carried out to define the morphological and growth characteristics of Poa pratensis L. (Kentucky bluegrass) 'Pureundul' native to Korea. Poa pratensis 'Pureundul' was collected from the belt highway around Mt. Uam located in Naedeok-dong, Cheongju City, Chungcheongbuk-do Province on May 5, 1995. The morphological characteristics of 'Pureundul' were compared with those of 205 individuals of native Poa pratensis collected throughout the nation from June 11, 2000 to June 21, 2003. The findings were as follows : The height of plant was 28.2cm but increased to 40.0cm at the flowering time. The height of first node from the base was 6.8cm and the length and width of leaf were 17.3cm and 2.9mm, respectively. The length of a spike was 7.9cm. Based on these morphological characteristics, 'Pureundul' was defined medium type Kentucky bluegrass. Visual quality(1~9), visual color and visual density were measured. The visual quality, color and density of 'Pureundul' were not superior to those of introduced species but above the average other native species. The damages from the diseases during summer resulted in poorer visual quality of color of 'Pureundul'. But the spread of the diseases was slower in 'Pureundul' than other native species, and accordingly 'Pureundul' didn't suffer from more quality deterioration from July to September during which the diseases broke out. Entering fall, 'Pureundul' showed high quality comparable to that of the introduced species. If 'Pureundul' is put to breeding by implementing pest control in summer and introducing disease tolerant genes, it will be used to make greens of greater quality than now.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.2
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• pp.21-26
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• 2003

The purpose of this study was to investigate morphological characteristics of 153 wild grown Poa pratensis collected from various areas of Korea and to see correlation among morphological characteristics and visual rating. Morphological characteristics such as plant height, leaf length, leaf width were measured. The collected Poa pratensis plants showed various morphological differences. The plant height of Poa pratensis ranged from 4.5 to 40.0cm. Poa pratensis leaf length ranged 3.0 to 30.2cm and leaf width ranged 1.0 to 5.0mm. The mean values of Poa pratensis height, leaf length and leaf width were 18.2cm, 13.1cm and 2.7mm respectively. The Poa pratensis plots were also visually rated 1 to 9 scale throughout the growing season for their overall characteristics as turfgrass. The height, leaf length, leaf width and visual rating had significant positive correlations. Especially the height and leaf length had a highly significant positive(r=0.74) correlation.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2006.11a
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• pp.399-401
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• 2006

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.76-81
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• 2013

This study was performed to find the effective post-emergence herbicides to control of Poa annua that has already emerged from the soil in Kentucky bluegrass. A total of 8 treatments consist of various post-emergence herbicides applied at recommended concentration or lower concentration than recommended concentration to prevent Kentucky bluegrass injury in this study. Methiozolin showed the least injury in Kentucky bluegrass during 40 days after treatments and there were no footprints by methiozolin in creeping bentgrass green during 20 days. However, Poa annua control was 60.4%, which was less than those of other 7 treatments in this study. Both of asulam sodium and iodosulfuron plus asulam sodium exhibited the higher Poa annua control of 81.7% and 82.2% respectively without serious injury in Kentucky bluegrass during 40 days, and they showed a slight footprints damage in creeping bentgrass green. On the other hand, critical Kentucky bluegrass injuries and the vivid and numerous footprints were occurred in treatments of trifloxysulfuron-sodium, foramsulfuron, rimsulfuron and flazasulfuron, even though they were applied with only 1/4 of recommended concentration. Methiozolin is available to reduce gradually Poa annua population on Kentucky bluegrass without severe turfgrass damage. Asulam sodium or iodosulfuron plus asulam sodium could be useful to remove Poa annua by spot treatment but it is prohibited to spray directly on green even spot.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.1
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• pp.69-81
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• 2010

The purpose of this study is to analyze the growth characteristics of native Kentucky bluegrass (Poa pratensis L.) collected in Korea. Out of Kentucky bluegrasses collected in 2000 and 2008, eight ecotypes ("Pyengchang," "Gongju," "Inje," "Donggang," "Hwasun," "Pureundle," "Cheongsong," and "Geumsan") were planted in experimental fields and pots on May 11, 2008 and May 3, 2009, respectively, for analyzing their growth characteristics. Data such as visual quality (1-9), visual density (1-9), visual color (1-9), plant height, leaf length and leaf width were analyzed. The visual quality of "Pyengchang," "Inje" and "Gongju" were enhanced compared to the rest native ecotypes of Kentucky bluegrass. "Pyengchang" showed the best visual density while "Gongju" and "Inje" showed almost evenly favorable density. However, "Pureundle," "Cheongsong," and "Geumsan" represented loose density due to the damage from the summer climate of high temperature and humidity in 2009. As for visual color, "Pyengchang" was also ranked first, maintaining high values of at least 7.6 even in the summer climate of high temperature and humidity. "Donggang" showed good color immediately after planting in the experimental field in 2008, however, undesirable color due to the damage from the summer climate of high temperature and humidity in 2009.

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.241-246
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• 2015

To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS-binding lytic bacteriophage. A non-virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2-N6, was established through in vivo pathogenicity and protection efficacy tests. SR2-N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2-N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.

• Asian Journal of Turfgrass Science
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• v.15 no.1
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• pp.15-20
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• 2001

Two types of annual bluegrass have been reported, and those consist of annual type (Poa annua ssp. annua) and perennial type (Poa annua ssp. reptans). As a weed, annual bluegrasses are commonly found in putting greens and fairways in many golf courses. Due to its strong competitiveness such as tremendous seed reproduction rate a year, prostrate growth habit, and no herbicide availability, annual bluegrasses have been considered as one of the most hard-to-control weeds in turf management systems. A growth chamber study was conducted to determine seed dormancy and to understand seed germination characteristics of annual bluegrass (Poa annua ssp. annua). Freshly harvested seeds showed 80 and 55% germination at 30 and $35^{\circ}C$, respectively, indicating that the optimum temperature of annual bluegrass is $30^{\circ}C$. However, the seed germination occurred only under light condition at any given temperature. This result demonstrated that light is prerequisite for the seed germination, and no primary dormancy of annual bluegrass seed exists. Secondary seed dormancy induced by unfavorable temperatures and dark condition was broken through 4 to 6 wk-storage at $4^{\circ}C$ with moisture, and the stored seeds germinated at $20^{\circ}C$ even under the dark. In red and far-red light trial, fresh seeds resulted in 40% germination under red while no seed germination occurred under far-red light condition, indicating that phytochrome Pr and Pfr could be related to annual bluegrass seed germination. When the far-red light replaced the red the germination was recovered, but this reversibility did not reach to the germination level under the red light only. This result implied that other lights than red and far-red would play an important role on seed germination of annual bluegrass.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.919-933
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• 2021

We hypothesized that the unsaturated fatty acid palmitoleic acid (POA) could promote the expression of adipogenic/lipogenic genes in bovine skeletal muscle satellite cells (BSCs). The BSCs were cultured in a growth medium containing 10% fetal bovine serum. When the cells reached 80%-90% confluence, we used the differentiation medium with 5% horse serum for differentiation for 96 h. The differentiation medium contained 50 µM, 100 µM and 200 µM POA. Control BSC were cultured only in differentiation media. Compared with the control BSC, the POA BSC significantly up-regulated the expression of paired box 3 (Pax3) and paired box 7 (Pax7) and down-regulated myogenin gene expression (p < 0.01), which indicates a depression in muscle fiber development. However, all POA treatments up-regulated the expression of the adipocyte transcription factors peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein alpha and beta (C/EBP α and C/EBP β), and other genes (p < 0.01) and increased the expression of PAT-family proteins and the concentration of adiponectin in the media. These results indicate that POA can convert part of BSCs into adipocytes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.101-105
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• 2024

4H-SiC power metal-oxide-semiconductor field effect transistors (MOSFETs) have been developed to achieve lower specific-on-resistance (R_on,sp), and the gate oxides have been thermally grown. The poor channel mobility resulting from the high interface trap density (D_it) at the SiO₂/4H-SiC interface significantly affects the higher switching loss of the power device. Therefore, the development of novel fabrication processes to enhance the quality of the SiO₂/4H-SiC interface is required. In this paper, NO post-oxidation annealing (POA) by using the conditions of N₂ diluted NO at a high temperature (1,300℃) is proposed to reduce the high interface trap density resulting from thermal oxidation. The NO POA is carried out in various NO ambient (0, 10, 50, and 100% NO mixed with 100, 90, 50, and 0% of high purity N₂ gas to achieve the optimized condition while maintaining a high temperature (1,300℃). To confirm the optimized condition of the NO POA, measuring capacitance-voltage (C-V) and current-voltage (I-V), and time-of-flight secondary-ion mass spectrometry (ToF-SIMS) are employed. It is confirmed that the POA condition of 50% NO at 1,300℃ facilitates the equilibrium state of both the oxidation and nitridation at the SiO₂/4H-SiC interface, thereby reducing the D_it.