• Journal of the Korean Geographical Society
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• v.49 no.5
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• pp.728-746
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• 2014

The purpose of this study is to analyze the influence of the selective migration of young age group and the stage migration which has proceeded through generations, on the transition of fertility and the population growth in the rural and urban in the case of Jeollabuk-do. For this, we use O-D matrix of 20-34 age group, the distribution of that group and women of child bearing age, and vital statistics in 1970-2010. The major findings of this study are as follows. First, the outflows from their birth place are common and dominant features of 20-34 age group in each time. Second, there is the stage migration which preceding generation moved from the rural areas to the cities in Jeollabuk-do and following generation has moved from the cities to Seoul metropolitan area. Third the selective outflow migration of young age group has leaded to reduction of the childbearing population, declining birthrate, aging and natural population decline. Due to the stage migration, these depopulation processes occurred in rural area in the past, and currently it expands to the cities with about 15 years time gap. In fact, there have been the natural population decrease which annual number of deaths exceed that of births from the late 1980s in the most rural areas and in the early 2000s, such a phenomenon has been confirmed also in urban areas. Therefore, this study concludes that the stage migration through generations is one of the crucial factor to the population growth in local cities and also brings out the step-wise population decrease in settlement hierarchies.

• Korean Journal of Metals and Materials
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• v.49 no.8
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• pp.596-600
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• 2011

Thermal degradation behavior of a $WO_3-TiO_2$ monolithic catalyst was investigated in terms of structural, morphological, and physico-chemical analyses. The catalyst with 4 wt.% $WO_3$ contents were prepared by a wet-impregnation method, and a durability test of the catalysts were performed in a temperature range between $400^{\circ}C$ and $800^{\circ}C$ for 3 h. An increase of thermal stress decreased the specific surface area, which was caused by grain growth and agglomeration of the catalyst particles. The phase transition from anatase to rutile occurred at around $800^{\circ}C$ and a decrease in the Brønsted acid sites was confirmed by structural analysis and physico-chemical analysis. A change in Brønsted acidity can affect to the catalytic efficiency; therefore, the thermal degradation behavior of the $WO_3-TiO_2$ catalyst could be explained by the transition to a stable rutile phase of $TiO_2$ and the decrease of specific surface area in the SCR catalyst.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.153-162
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• 2010

Abies holophylla Maxim. is a shade tolerant species that has potential to be used for continuous cover forestry system. Stand structure and natural regeneration of A. holophylla stands in Yong-In area located in the central part of Korea was investigated to estimate the self sustainability of A. holophylla plantation. Species composition, diameter at breast height (DBH) and height distribution of trees larger than 2 cm DBH were measured in ten stands in three study sites of Jeongsu-ri, Daedae-ri, and Hodong. Species and coverage of shrub layer, and A. holophylla seedlings were also investigated. While A. holophylla in non-managed stands (Jengsuri and Daedae-ri study sites) had the importance value of 40% and showed continuous diameter and age distribution, A. holophylla in Hodong site had narrow bell-shaped DBH distribution mostly concentrating between 25-35 cm DBH classes, and single canopy structure. Abies holophylla stands in Hodong have experienced occasional thinning and selective cutting. The correlation coefficient between age-DBH was significant but low ($R^2$=0.2, P=0.03), and similar aged A. holophylla had diverse DBH values. Continuos DBH distribution and multi-canopy structure of A. holophylla stands in Jeongsu-ri site show that natural regeneration of A. holophylla has been continuously occurred in this area. Seedling density of A. holophylla was between 2000 and 33000/ha, however, the number of trees in 2-5 cm DBH class was only 40-150 trees/ha, implying that the survival rate of seedlings is not high. Continuous natural regeneration and 0.6 cm/year of diameter growth rate of A. holophylla indicate that this area could be an appropriate habitat for this species, and A. holophylla plantation in this region seem to persist suggesting the possibility of managing the stands for continuous cover forestry system as well as selective harvesting practices.

• Journal of Family Relations
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• v.22 no.4
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• pp.3-29
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• 2018

Objectives: This study is designed to explore and understand what professional identity and professional development are like in family counselors. Method: This study to achieve its purpose, collected data through in-depth interview with fifteen(15) family counselors through grounded theory approach. Results: Major research findings can be summarized as follows. 176 concepts were drawn through open coding, again classified into 47 categories and finally into 18 subcategories. Through selective coding, 'growing as an expert in family counseling through continuous exertions for growth' appeared as core category. Through this process, the types of professional development in family counselors were classified into job pursuing type, self achieving type, self understanding type, and volunteering type. Through process analysis, family counselors' professional development could be divided into three steps with the course of time: step of immersion, self-understanding and acceptance, and integration. Based on this, the hypothetical relations in four areas: personal area, family area, interpersonal area, and vocational area were summarized in statements. Conclusion: This study is significant in that it attempted to establish a theory to explain the professional identity, development and influence factors shown in family counselors. It also provides those who hope to grow as expert in family counseling with long-term visions and implications for family counselor training and supervision. In this study, the suggestions on the tasks to check and solve the factors for improving and supporting the foundations of family counselors' professional identities by highlighting the family counselors own identify that is different from other counselors are expected to be used as primary data for preparing laws and regulations related to family counseling in the future.

• Journal of the Korean Geographical Society
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• v.49 no.4
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• pp.525-545
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• 2014

This study seeks to clarify the influence of the stage migration which has proceeded through generations, on the population growth of local cities in the case of Jeollabuk-do. For this, setting to baby boomer as parents generation and echo boomer as their children, this study traces each generation's birth, distribution and the process of selective migration using aggregate level data. And the stage migration is analyzed by O-D, divided into three regions in each; Jeollabuk-do rural areas, Jeollabuk-do cities and other provinces. The major findings of this study are as follows. First, it was estimated that the number of the baby boomer births in Jeollabuk-do rural areas was seven times more numerous than in cities. Second, both rural and urban born baby boomers overwhelmingly moved into other provinces, especially Seoul metropolitan area and metropolis in their selective migration processes. However, there was also migration stream from rural areas to cities in Jeollabuk-do and the amount of this stream was approximately equal to the amount of outflux from cities in Jeollabuk-do to other provinces. Third, due to baby boomers' stage migration, from rural to urban, echo boomers were born in cities more than in rural areas. Fourth, urban born echo boomers still have moved into other provinces just like their parents generation in selective migration process. But comparing with baby boomer, the number of echo boomers influx from rural areas to cities has decreased. Consequentially the population of echo boomer in Jeollabuk-do cities also has decreased. Finally, the stage migration has been a basic cause of the social growth of urban population, and also influenced on the natural growth, closely connected with migrants' life course, such as marriage, childbirth and rearing. Therefore, this study concludes that the stage migration through generations is one of the crucial factor to understand the population growth in local cities.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.12
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• pp.1171-1176
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• 2012

The selective patterning of a carbon nanotube (CNT) forest on a Si substrate has been performed using a femtosecond laser. The high shock wave generated by the femtosecond laser effectively removed the CNTs without damage to the Si substrate. This process has many advantages because it is performed without chemicals and can be easily applied to large-area patterning. The CNTs grown by plasma-enhanced chemical vapor deposition (PECVD) have a catalyst cap at the end of the nanotube owing to the tip-growth mode mechanism. For the application of an electron emission and biosensor probe, the catalyst cap is usually removed chemically, which damages the surface of the CNT wall. Precise control of the femtosecond laser power and focal position could solve this problem. Furthermore, selective CNT cutting using a femtosecond laser is also possible without any phase change in the CNTs, which is usually observed in the focused ion beam irradiation of CNTs.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.238-238
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• 2016

백색 발광다이오드(LED)는 기존 조명(백열등, 형광등)에 비하여 월등히 에너지를 절약할 수 있어 이미 상업적, 정책적으로 교체가 진행 중이다. 현재의 백색 LED를 만들기 위해서는 필연적으로 형광체를 사용해야 한다. 그러나 이 형광체에 의한 (a)Stocks 에너지변환에 의한 효율감소, (b)높은 공정비용, (c) 열적 안정성 저하를 피할 수 없다. 우리는 유기금속화학증착(MOCVD)과 선택적성장(selective-area epitaxial growth)방법을 이용하여 형광체를 쓰지 않고 3차원 구조체를 이용하여 백색 LED를 제작하여 전기구동하였고 전류의 세기를 변화하여도 지속적으로 동일한 백색광을 유지함을 보였다. 광학적 분석(cathodoluminescence)과 구조적 분석(scanning electron microscope, transmission electron microscope)을 진행하여 구조를 살피고 백색 발광의 원인을 분석하였다. 또한, 고배율 대물렌즈를 사용한 공간분해 광학적 분석실험(photoluminescence와 electroluminescence 데이터를 비교)으로부터 국소적 운반자의 주입효율을 분석하는 방법을 고안하여 실험하였다.[1] 향후 이 방법은 3차원 구조체 LED뿐 아니라 2차원 LED에도 응용하여 LED의 주입효율을 분석하는데 유용하게 사용될 수 있을 것이라 기대된다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.6
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• pp.291-298
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• 2012

Carbamoylphosphate (CMPO) [CMPO analogue; 2-(diphenylphosphoryl)-N-(3-(triethoxysilyl)propyl)acetamide]silane, as a functional self-assembled molecules, grafted mesoporous silicates were prepared by simple hydrolysis and condensation reaction. Pore sized tailored mesoporous silicates such as MCM-41, SBA-15, or amorphous silica nanoparticles were adopted as host materials. The surface area of ordered mesoporous silicates was ranged from 680 $m^2/g$ to 1310 $m^2/g$ with different pore diameters that estimated to be ca. 2.3~9.1 nm by BJH method. Among the OMMs host materials, SBA-15(II) has higher loading ratio (~35 wt%) of CMPO derivative than other OMMs. Accessibility to CMPO silane functional groups in the surface of mesoporous silicas was studied by lanthanide ions sorption experiments. All of the CMPO modified OMMs favors the smaller Eu(III) and Nd(III) cations than La(III) for relative larger ionic radius.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.4
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• pp.211-221
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• 2021

The Rabbit grass(Trifolium Repens, call it 'Clover') is a representative harmful plant of lawn, and it starts growing earlier than lawn, forming a water pipe on top of the lawn and hindering the photosynthesis and growth of the lawn. As a result, in competition between lawn and clover, clover territory spreads, but lawn is damaged and dried up. Damage to the affected lawn area will accelerate during the rainy season as well as during the plant's rear stage, spreading the area where soil is exposed. Therefore, the restoration of damaged lawn is causing psychological stress and a lot of economic burden. The purpose of this study is to distinguish clover which is a representative harmful plant on lawn, to identify the distribution of damaged areas due to the spread of clover, and to review of changes in vegetation before and after the eradication of clover. For this purpose, a time series analysis of three vegetation indices calculated based on images of convergence Drone with RGB(Red Green Blue) and BG-NIR(Near Infra Red)sensors was reviewed to identify the separation between lawn and clover for selective eradication, and the distribution of damaged lawn for recovery plan. In particular, examined timeseries changes in the ecology of clover before and after the weed-whacking by manual and brush cutter. And also, the method of distinguishing lawn from clover was explored during the mid-year period of growth of the two plants. This study shows that the time series analysis of the MGRVI(Modified Green-Red Vegetation Index), NDVI(Normalized Difference Vegetation Index), and MSAVI(Modified Soil Adjusted Vegetation Index) indices of drone-based RGB and BG-NIR images according to the growth characteristics between lawn and clover can confirm the availability of change trends after lawn damage and clover eradication.

• Korean Journal of Metals and Materials
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• v.50 no.3
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• pp.201-205
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• 2012

The effects of various manganese precursors for the low-temperature selective catalytic reduction (SCR) of $NO_x$ were investigated in terms of structural, morphological, and physico-chemical analyses. $MnO_x/TiO_2$ catalysts were prepared from three different precursors, manganese nitrate, manganese acetate(II), and manganese acetate(III), by the sol-gel method. The manganese acetate(III)-$MnO_x/TiO_2$ catalyst tended to suppress the phase transition from the anatase structure to the rutile or the brookite after calcination at $500^{\circ}C$ for 2 h. It also had a high specific surface area, which was caused by a smaller particle size and more uniform distribution than the others. The change of catalytic acid sites was confirmed by Raman and FT-IR spectroscopy and the manganese acetate(III)-$MnO_x/TiO_2$ had the strongest Lewis acid sites among them. The highest de-NOx efficiency and structural stability were achieved by using the manganese cetate(III) as a precursor, because of its high specific surface area, a large amount of anatase $TiO_2$, and the strong catalytic acidity.