• 농촌지도와개발
• /
• 제11권1호
• /
• pp.83-93
• /
• 2004

This paper investigated the characteristics of population structure and the determinants of population movement in the south west area of Kyonggi-do by grouping 9 cities in 3 categories and using Panel data of $1995{\sim}2001$. The major findings of this paper were identified as follows : 1) The population structure of regions was different to the stages of urbanization. The ratio of child and elder dependency was high in the rural regions and low in the urbanized regions. It was due to the movement of economically active population of $20{\sim}40$ aged groups, from rural regions to urban regions. This means that more productive segments of the rural population leave the country to the city. In addition. The ratio of male to female was higher in $20{\sim}40$ aged groups for rural regions. This suggested that young females moved from rural regions to urban regions more than young males in the process of industrialization. 2) Based in pooling regression, income was the most significant determinant that could explain the inter-regional and intra-regional movement of population for south west area studied, The next one was educational opportunity variable. The coefficients of income and education were 0.5, 0,7 for intra-regional migration and 0.01, 0.02 for interregional migration indicating that Todaro's hypothesis could be tested well rather than Tiebout' model for this area.

• 천문학회보
• /
• 제37권1호
• /
• pp.74.1-74.1
• /
• 2012

It is known that the diffuse H${\alpha}$ halos around bright H II regions are more extended than the dust-scattered halos around point sources and the line ratios [S II] ${\lambda}$6716/H${\alpha}$ and [N II] ${\lambda}$6583/H${\alpha}$ observed outside of bright H II regions are generally higher than those in H II regions. These observational facts have been regarded as evidence against the dust-scattering origin of the diffuse H${\alpha}$ emission and the effect of dust-scattering has been neglected in studying the diffuse H${\alpha}$ emission. In this paper, we find, however, that dust-scattered halos of H II regions should be more extended than those of point sources and is in good agreement with the observed H${\alpha}$ profiles around H II regions. We also found that the observed line ratios [S II]/H${\alpha}$, [N II]/H${\alpha}$, and He I ${\lambda}$5876/H${\alpha}$ in the diffuse regions can be well reproduced with the dust-scattered halos around H II regions which are photoionized by late O- and/or early B-type stars in the interstellar medium with the abundances close to those of the warm neutral medium. Therefore, we conclude that the diffuse H${\alpha}$ emission may originate mostly from the dust-scattering.

• 대한지리학회지
• /
• 제38권4호
• /
• pp.562-574
• /
• 2003

이 연구는 아주 최근에 새롭게 제기된 세계도시지역론을 고찰하고 이에 기초하여 한국의 지역발전 정책을 위한 함의를 제안하고 있다. 세계의 주요한 거대도시지역으로. 이루어진 정치ㆍ경제적 조직체 또는 다중심적 구조를 지닌 새로운 규모의 도시조직으로 정의되는 세계도시지역은 세계경제의 역동적인 성장뿐만 아니라 지역발전도 동시에 유발함으로써 세계화시대에서 대안적인 신지역주기 발전모델로 평가된다. 한국에서 세계도시지역모델의 정책적 적용은 특히, 비수도권의 거대도시지역의 세계적 경쟁력 강화와 수도권과 비수도권 간의 극심한 지역격차를 완화하기 위해서 필요시 된다. 그러나 부산, 대구, 광주, 대전 등의 비수도권의 광역시가 세계도시지역으로 발전하기 위해서는 시ㆍ도 통합과 지방분권과 같은 제도개혁이 선행되지 않으면 안 된다.

• 천문학회보
• /
• 제36권1호
• /
• pp.36.1-36.1
• /
• 2011

It is generally believed that eruptive phenomena in the solar atmosphere such as solar flares and coronal mass ejections (CMEs) occur in the solar active regions with complex magnetic structures. Magnetic helicity has been recognized as a useful parameter to measure the complexity such as twists, kinks, and inter-linkages of magnetic field lines. The objective of this study is to understand a long-term (a few days) variation of magnetic helicity in active regions and its relationship with the energy buildup and instability leading to flares and CMEs. Statistical studies of flare productivity and magnetic helicity injection in about 400 active regions were carried out. The temporal variation of magnetic helicity injected through the photosphere of active regions was also examined related to 46 CMEs. The main findings in this study are as follows: (1) the study of magnetic helicity for active regions producing major flares and CMEs indicates that there is always a significant helicity injection through the active-region photosphere over a long period of 0.5 - a few days before the flares and CMEs; (2) for the 30 CMEs under investigation, it is found that there is a fairly good correlation (linear correlation coefficient of 0.71) between the average helicity injection in the CME-productive active regions and the CME speed. Beside the scientific contribution, a major impact of this study is the observational discovery of a characteristic variation pattern of magnetic helicity injection in flare/CME-productive active regions which can be used for the improvement of solar eruption forecasting.

• Korean Journal of Radiology
• /
• 제22권7호
• /
• pp.1194-1202
• /
• 2021

Objective: To investigate the age-dependent changes in regional cerebral blood flow (CBF) in healthy adults by fitting mathematical models to imaging data. Materials and Methods: In this prospective study, 90 healthy adults underwent pseudo-continuous arterial spin labeling imaging of the brain. Regional CBF values were extracted from the arterial spin labeling images of each subject. Multivariable regression with the Akaike information criterion, link test, and F test (Ramsey's regression equation specification error test) was performed for 7 models in every brain region to determine the best mathematical model for fitting the relationship between CBF and age. Results: Of all 87 brain regions, 68 brain regions were best fitted by cubic models, 9 brain regions were best fitted by quadratic models, and 10 brain regions were best fitted by linear models. In most brain regions (global gray matter and the other 65 brain regions), CBF decreased nonlinearly with aging, and the rate of CBF reduction decreased with aging, gradually approaching 0 after approximately 60. CBF in some regions of the frontal, parietal, and occipital lobes increased nonlinearly with aging before age 30, approximately, and decreased nonlinearly with aging for the rest of life. Conclusion: In adults, the age-related perfusion patterns in most brain regions were best fitted by the cubic models, and age-dependent CBF changes were nonlinear.

• 한국생활과학회지
• /
• 제19권1호
• /
• pp.51-61
• /
• 2010

The purpose of the current study was to select vulnerable regions with insufficient child care services based on an in-depth investigation of diverse regional characteristics and to establish a practical goal for the expansion of public child care centers through identifying priority regions in foremost need of public child care centers out of the vulnerable regions. The vulnerable regions were selected from both urban and rural areas with particular criterions to determine their critical situation. First of all, the number of children aged zero to five, private and public child care centers, and capacity and enrolment of the regional child care center were selected from towns (Eup) and townships (Myeon) within rural areas and neighborhoods (Dong) within urban areas to calculate the capacity fulfillment. Specifically, a dense population of low-income families inhabited within urban areas defined the region's vulnerable status for the analysis, whereas poor accessibility of a child care center within rural areas correspond to the lack of child care services. The analytical result displayed that a total of 456 towns and townships did not acquire child care centers. Out of 456 towns and townships, 162 were selected as priority regions. On the other hand, 546 neighborhoods corresponding to upper 30 percentiles of urban area where children receive basic subsidy for low income families were selected as vulnerable regions. Out of 546 neighborhoods, 243 were selected as priority regions according to the analytical result.

• 한국수산과학회지
• /
• 제27권3호
• /
• pp.314-325
• /
• 1994

Characteristics of climate in the eastern coastal regions of Korean Peninsula were studied using the meteorological and coastal sea surface temperature (SST) data which were compiled from 1961 to 1990. In the winter half year (from October to March), air temperature (AT) and precipitation of the eastern coastal regions were considerably higher than those of the western and inland regions, but relative humidity was $8{\sim}15\%$ lower. AT of coastal regions was closely related to the variation of coastal SST. These characteristics were more noticeable in the eastern coastal areas and in lower latitude regions. Quantitatively, the $1.0^{\circ}C$ variation of coastal SST may have resulted in the $1.0^{\circ}C{\sim}1.5^{\circ}C$ variation for AT in coastal regions. In the same way as temperature, vapor pressure in coastal regions was also influenced by coastal SST. Relative humidity change corresponding to the $1.0^{\circ}C$ variation of coastal SST was $3.7\%{\sim}6.5\%$. Net heat exchange amounts were positive (sea surface gaining energy) in all coastal regions. Sea surface gained net heat from March to September, and lost it from October to February. Variation of AT in coastal regions was also related to the sensible and latent heat exchanges. Sensible and latent heat amount corresponding to the $1.0^{\circ}C$ variation of AT were $10Wm^{-2}$ at Kangnung, and $8Wm^{-2}$ at Pohang and $13Wm^{-2}$ at Pusan.

• 한국멀티미디어학회논문지
• /
• 제5권6호
• /
• pp.616-624
• /
• 2002

본 논문에서는 영상에 포함된 중심 객체를 추출하는 방법에 대해 제시한다. 중심 객체는 촬영의 중심이 되어 영상의 중앙 부분에 비교적 큰 면적을 차지하는 객체로 정의하는데 영상 내용에 대한 중요한 정보를 제공한다. 중심 객체 추출을 위해 우선 입력 영상에 대해 해상도를 줄여가며 영상 분할하고 분할된 결과에 대해 계층적 영역 병합을 수행함으로써 객체가 많은 수의 영역으로 세분화되어 영상 분할되는 것을 방지할 수 있도록 하였다. 분할된 각 영역은 영상의 경계와 접하는 경계 영역과 그 외의 비경계 영역으로 분류하였다. 비경계 영역은 중심 객체에 해당될 가능성이 있는 영역으로써, 이들 중에서 영상 중심 부근에서 가장 큰 크기를 차지하는 영역이 핵심객체영역으로 선택된다. 또한 경계 영역 중에서 영상의 네 모서리에 인접하는 영역은 핵심배경영역으로 선택되어 핵심객체영역과 함께 중심 객체 추출에 이용된다. 각 비경계 영역은 핵심 배경영역및 핵심객체영역과 칼라 분포 유사도출 비교하여 배경영역과 전경영역으로 분류된다. 핵심객체영역 및 핵심객체영역과 연결성을 가지는 전경영역이 최종 중심 객체로 선택된다. 본 논문에서 제안된 방법은 비교적 복잡한 배경을 갖는 영상에 대해서도 어느 정도 만족할 만한 결과를 얻을 수 있었다.

• 정보처리학회논문지:소프트웨어 및 데이터공학
• /
• 제6권4호
• /
• pp.185-192
• /
• 2017

여러 과학 분야에서 측정 또는 시뮬레이션의 결과로 2차원 배열 데이터가 활발히 생성되고 있다. 현재 배열 데이터에 대한 다양한 질의 처리 기법들이 연구되고 있으나 2차원 배열 데이터에서 크기가 미리 알려져 있지 않은, 값이 서로 유사한 구역을 찾는 문제는 거의 다루어지지 않았다. 따라서 본 논문에서는 주어진 2차원 배열 데이터에서 사용자가 지정한 값 이상의 크기를 갖는, 원소 값들이 서로 유사한 구역을 빠르게 찾는 방법을 제안한다. 본 논문의 제안 방법은 2차원 배열의 각 원소 쌍에 대해, 해당 원소로만 이루어진 크기가 1인 구역부터 시작하여 두 구역을 동일한 모양을 유지하면서 오른쪽 및 아래쪽으로 단계적으로 확장시켜나간다. 만약 두 구역의 값의 차이가 사용자가 지정한 값 이상으로 커지면 확장을 중단한다. 따라서 제안 방법은 배열에서 유사 구역이 될 가능성이 있는 부분들만 접근하여 유사 구역을 효율적으로 찾아낼 수 있다. 본 논문에서는 성능 분석과 다양한 실험을 통해 제안 방법이 매우 효율적으로 유사 구역을 찾을 수 있음을 보인다.

• Journal of Ginseng Research
• /
• 제39권4호
• /
• pp.338-344
• /
• 2015

Background: Ginseng (the roots of Panax ginseng Meyer) is a well-known traditional Oriental medicine and is now widely used as a health food. It contains several types of ginsenosides, which are considered the major active medicinal components of ginseng. It has recently been reported that the qualitative and quantitative properties of ginsenosides found in ginseng may differ, depending on cultivation regions, ages, species, and so on. Therefore, it is necessary to study these variations with respect to cultivation ages and regions. Methods: In this study, 3-6-yr-old roots of P. ginseng were collected from three different cultivation regions. The contents of five ginsenosides (Rb1, Rd, Rc, Re, and Rgl) were measured by rapid resolution liquid chromatography coupled with quadruple-time-of-flight mass spectrometry. The Kruskal-Wallis Rank sum test and multiple t test were used for comparative analysis of the data to evaluate the dynamic changes in the accumulation of these ginsenosides affected by cultivation regions and ages. Results: The content and composition of ginsenosides varied significantly among specimens collected from different cultivation regions and having different cultivation ages. For all samples, the content of Rg1 and Re ginsenosides increases with age and this rate of increase is different for each sample. The contents of Rb1, Rc, and Rd varied with cultivation ages in samples from different cultivation regions; especially, Rb1 from a 6-yr-old root showed approximately twofold variation among the samples from three cultivation regions. Furthermore, the content of Rb1 highly correlated with that of Rd (r = 0.89 across all locations and ages). Conclusion: In our study, only the contents of ginsenosides Rg1 and Re were affected by the root age. Ginsenosides Rb1, Rc, and Rd varied widely with ages in samples from different cultivation regions.