• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.182-187
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• 2015

The growth and characterization of micro sized AlGaN array structures selectively grown by metal organic chemical vapor deposition (MOCVD) on GaN stripes are reported. The shape of the AlGaN array structures depends on the size of exposed area for selective growth. The AlGaN array structures grown selectively on relatively large exposed area have regular shapes resembling those of the GaN stripes on the substrate, while samples selectively grown on relatively small exposed area have irregular shapes. The phonon frequency of the AlGaN array structures increases with increasing Al composition in the AlGaN structure. However, at relatively high Al composition (x = 0.28 in this research), the phonon frequency decreases slightly from the expected value not only because of large tensile strain associated with large differences between the lattice constants of the AlGaN structure and underlying GaN stripes but also changes of crystal facet direction during the selective growth.

• Journal of Korean Society of Forest Science
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• v.64 no.1
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• pp.47-51
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• 1984

Hybrids among some southern pines, Pinus rigida, Pinus taeda and Pinus serotina, were tested in Chunbuk area in order to investigate their adaptability to Korean climate and soils. The results were summarized as follows; 1) Hybrids between P. rigida and P. raeda showed good growth among interspecific hybrids of southern pines tested. In particular, P. taeda${\times}$P. rigida showed remarkable growth in Chunbuk area. 2) The survival rate of P. taeda was extremely low, probably because of cold susceptibility. 3) Volume growth was correlated with width and length of cone, length of needle and needle sheath at the 1% level. 4) Hybrids were generally located between the parents in cluster analysis.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.3
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• pp.138-148
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• 2018

Land use regulations introduced for rationalization of land use due to the diversification of socio-economic development, resulting in inconvenience to the people's economic life, have recently changed the paradigm due to deregulation. In this study, the potential areas for urban growth in the Busan area were derived by simulating using the CA model and spatial characteristics were analyzed along with land use regulated areas. The analysis examined whether the land use regulations were actually intended to curb urban growth and promote the efficiency of land use, or if there were other factors that could cause inconvenience to the people's lives. The analysis showed that the greenbelt zones in areas with high development pressure outside urban areas were acting as land use regulations, but there were multiple regulations on land use in many areas. Therefore, it is deemed that various approaches and reviews will be needed, including reconsideration of multiple regulations in areas with high urban growth potential, while maintaining the net function of land use regulations.

• Corrosion Science and Technology
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• v.6 no.3
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• pp.103-111
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• 2007

The effect of stress factors on the growing process of stress corrosion cracking (SCC) of the sensitized 18-8 stainless steel in high temperature water was investigated using equations of crack growth rate derived from applying electric circuits to SCC corrosion paths. Three kinds of cross sections have to be considered when electric circuit is constructed using total current. The first is ion flow passage area, $S_{sol}$, of solution in crack, the second is total dissolving surface area, $S_{dis}$, of metal on electrode of crack tip and the third is dissolving cross section, $S_{met}$, of metal on grain boundary or in base metal or in welding metal. Stress may affect each area. $S_{sol}$ may depend on applied stress, $\sigma_{\infty}$, related with crack depth. $S_{dis}$ is expressed using a factor of $\varepsilon(K)$ and may depend on stress intensity factor, K only. SCC crack growth rate is ordinarily estimated using a variable of K only as stress factor. However it may be expected that SCC crack growth rate depends on both applied stress $\sigma_{\infty}$ and K or both crack depth and K from this consideration.$\varepsilon(K)$ is expressed as ${\varepsilon}(K)=h_2{\cdot}K^2+h_3{\cdot}K^3$ when $h_{2}$ and $h_{3}$ are coefficients. Also, relationships between SCC crack growth rate, da/dt and K were simulated and compared with the literature data of JBWR-VIP-04, NRC NUREG-0313 Rev.2 and SKIFS Draft. It was pointed out in CT test that the difference of distance between a point of application of force and the end of starter notch (starting point of fatigue crack) may be important to estimate SCC crack growth rate. An anode dissolution current density was quantitatively evaluated using a derived equation.

• Journal of Life Science
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• v.11 no.2
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.

• STI Policy Review
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• v.1 no.1
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• pp.1-21
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• 2010

To achieve the "low carbon green growth" vision, the first step is securing core technologies. Therefore, S&T policy direction for green technology development is urgently needed. As of 2008, investment in green technology (GT) development hovered around 10% of the government's total R&D budget. Thus, the Korean government developed a plan to increase that percentage to 15%, by 2013. To develop reasonable investment strategies for green technology development, targeted strategies that reflect technology and market changes by green technology area are needed. However, the overall planning and coordination of national GT development is currently split among, approximately, 10 government ministries. To establish an efficient green technology development system, the so-called "Green Technology R&D Council" should be launched in collaboration with the Presidential Committee on Green Growth and the National Science and Technology Council. Furthermore, to build a solid foundation for commercializing the outcomes of GT development projects and promote GT transfer, the government should undertake two initiatives. First, the government should reinforce GT R&D performance management, by establishing a GT R&D performance management and evaluation system. Second, the government should implement the "customized packaged support for promoting green technology business rights and commercialization" and present "e-marketplace for market-oriented green technologies". Creating a pan-ministerial policy for GT development policy would necessitate restructuring the HR(Human Resources) development system, which is currently separated by technology area. Based upon mid/long-term HR supply and demand forecasts, the government should design differentiated HR development projects, continuously evaluate those projects, and reflect the evaluation results in future policy development. Finally, to create new GT-related industries, the "Green TCS (Testing, Certification, and Standards) System" needs to be implemented. For objective evaluation and diffusion of R&D results by green technology area, a common standardization plan for testing, analysis, and measurement, like the "Green TCS", should be developed and integrated.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.158-163
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• 1983

The purpose of this experiment was to find out fundamental data for the cultivation of sorghum-sudangrass hybrid. Leaf area index and dry matter accumulation were investigated with 3-levels of nitrogen application,15, 25, 35kg per 10a during the period of initial growth from the 8th leaf emergence to the late blooming stage. The results obtained were as follows: Leaf emergence increased as growth progressed and in the same pattern at all N-levels. After the heading stage, the value was 15 at all N-levels. Leaf area index (LAI) increased as growth progressed and rapidly till the booting stage. At 15kg N-level the values were larger till the ear formation stage, and at 35tg N-level the values were larger than other N-levels after the booting stage. At the late blooming stage LAI reached 8.13 at 35kg N-level. The value of dry matter accumulation was the highest at 35kg N-level at the late blooming stage, and as was the same in the value of crop growth rate (CGR). There was a tendency that before the booting stage the enlargement of leaf area contributed to dry matter accumulation and after the booting stage did the increase of net assimilation rate (NAR) .

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.1
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• pp.1-11
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• 2002

This study was conducted to reveal the effects of local climatic conditions on the early growth of Korean white pine progeny test stands. For this, stand variables such as mean DBH, mean height, basal area per hectare, and volume per hectare by stand age and locality were first measured and summarized for each stand. Based on these statistics, annual increments for 10 years from stand age 10 to 20 were calculated for each of stand variables. The effects of local climatic conditions as one of environmental factors on the growth were then analyzed by both a topoclimatological method and a spatial statistical technique. From yearly climatic estimates,30 climatic indices which affect the tree growth were computed for each of the progeny test stand. The annual increments were then correlated with and regressed on the climatic indices to examine effects of local climatic conditions on the growth. Gapyung area provided the best conditions for the early growth of Korean white pine and Kwangju area ranked second. On the other hand, the growth pattern in Youngdong ranked last overall as expected. It is also found that the local growth patterns of Korean white pine in juvenile stage were affected by typical weather conditions. The conditions such as low temperature and high relative humidity provide favor environment for the early growth of Korean white pine. Especially, it was concluded that the low temperature is a main factor influencing the early growth of Korean white pine based on the results of correlation analysis and regression equations developed far the prediction of annual increments of stand variables.

• Journal of the Korean Ceramic Society
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• v.41 no.12 s.271
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• pp.880-883
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• 2004

Carbon nanofibers could be selectively formed at the groove area of the MgO substrate using microwave plasma-enhanced chemical vapor deposition system. Iridium metal was used as a catalyst layer for the formation of the carbon nanofibers. The growth direction of the carbon nanofibers was vertical to the substrate surface. The selectively grown iridium-catalyzed carbon nanofibers show around $1.8V/{\mu}m$ turn-on voltage and $1.0\;mA/cm^2$ field emission current density at $2.65\;V/{\mu}m$ in the field emission measurement.

• Asian Journal of Turfgrass Science
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• v.15 no.2
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• pp.77-86
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• 2001

The experiments were carried out to investigate effect of shading rare on variegata appearance and leaf growth of variegated liriope (Liriope platyphylla Wang et Tang variegata Hort.) The plant was grown under four different light intensities such as 0(natural light intensity), 25, 50 and 75% shading conditions. Leaf variegata appearance was better in the light than in the shade. Leaf showed good growth at 0, 25% shading treatment, average leaf width and area of yellow part were highest at 0% shading treatment. As increased shading rate, number of stomate per unit area decreased. Total chlorophyll of the whole leaf and green part were reduced by increasing shading rate, while yellow part showed oppositely. In the epidermis, cell size of 75% shading treatment showed larger than those of 0% shading treatment.