• Korea journal of population studies
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• v.23 no.2
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• pp.39-77
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• 2000

The paper examines non-agricultural occupations of Korean immigrants in the Russian Far East from 1860s to 1930s. First of all, theoretical perspectives regarding immigrants\` job selection and positions in the labor market such as cultural theory, segmented labor market theory, human capital theory, and ethnic enclave theory were reviewed and then how these theories can be applied to various jobs of Korean immigrants including mining, fishing, small business, service, and miscellaneous jobs was studied. Next. this article points out that those theories cannot explain both supply and demand sides of migration simultaneously, suggesting the need to integrate two sides of migration. In order to fill out this gap in the literature, this paper suggests the integrative approach which combines supply side and demand side of migration. According to this model, several factors in the non-agricultural jabs which were affecting Korean immigration in the Russian Far East. were identified and discussed in relation with existing theoretical perspectives. Finally this paper concludes that, in order to understand Koran migration in the Russian Far East properly, we have to take into consideration simultaneously both supply-sided factors of immigration including farming-oriented characteristics of Koreans, Korean socio-economic problems preceding immigration, and self-dependent tendencies of Korean immigrants and demand-side factor like the Russian migration policy to the immigrants and various regional situations in the Russian Far East.

• Journal of Korea Spatial Information System Society
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• v.9 no.3
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• pp.17-24
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• 2007

The noise problem is one of the major problems associated with large cities and is considered important factor not only in maintenance but also in development of cities. Accordingly, the noise map is being increasingly used in city planning and design. However, the existing two-dimensional noise maps only show regional, planar distribution of noise. This study presented a method to build a data model for analyzing and visualizing noise levels at fine scale considering the vertical distribution of noise in a building. By expanding the 2D topology concept used in conventional GIS to 3D, it suggested a 3D GIS data model that makes 3D spatial queries, analyses and visualization possible and applied the proposed approach to building a 3D noise information system. By building and testing the system, the study showed different functionalities including 3D spatial queries and 3D visualization of noise levels varying temporally or according as the height of sound-proof walls. In each case, the population exposed to noise was quantitatively computed to illustrate the potential in the areas of city planning and design.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.12
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• pp.5081-5086
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• 2016

Background: Pathological factors, based mainly on immunohistochemistry (IHC) and histological differentiation, are mostly used to differentiate breast cancer (BC) subtypes. Our present aim was to describe the characteristics and survival of a relapsing BC patient cohort based on clinico-pathologic subtypes determined for the primary tumors. Methods: We used a clinico- pathological definition of BC subtypes based on histological grade (HG), estrogen receptor (ER), progesterone receptor (PgR),and epidermal growth factor receptor type 2 (HER2) expression assessed by IHC. We determined variables associated with loco-regional recurrence (LRR), second primaries (SP), systemic recurrence (SR) and post-recurrence survival (PRS). Results: Out of 1,702 patients, 240 (14%) had an event defined as recurrence. Those with recurrent disease were significantly younger than those without,and were initially diagnosed at more advanced stages, with larger tumors, greater lymph nodal involvement and higher HG. With a median follow up of 61 months (1-250), 4.6% of patients without recurrence and 56.6% of patients with an event defined as recurrence had died. The median PRS for the LRR group was 77 months; 75 months for those who developed a SP and 22 months for patients with an SR (p <0.0001). In SR cases, the median PRS was shorter for ER- tumors than for ER+ tumors (15 vs. 26 months, respectively; p = 0.0019, HR 0.44; CI: 0.25-0.44). Conclusions: Subtype, defined through classic histopathologic parameters determined for primary tumors, was found to eb related to type of recurrence and also to prognosis after relapse.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.535-543
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• 2016

This study has been carried out to evaluate the CBR characteristics and the correlations among every soil properties of National road in Yeongnam region. Total of 480 soil samples were collected from 41 administrative districts for more than 30 years. Their physical and mechanical properties such as natural water content, the Atterberg limit, No. 200 sieve passing, the compaction test and the CBR test results were involved. The soils in Yeongnam region, SM, SC, SP and CL by USCS have predominated approximately 79%. The test results show that average CBR values of gravel and sand range from 12.7% to 20.3% and those of silt and clay range from 4.8% to 7.1%. It means that average CBR values of fine grained soils are less than a half of coarse grained one. Natural water content, No. 200 sieve passing, optimum moisture content and maximum dry density of soils are well correlated with CBR values. Especially, it presents that No. 200 sieve passing is the best correlation factor with CBR value. If consider the partition off this region into 6 zones of classified by mother rock, the correlation between CBR value and every soil properties tends to increase. It is suggested that tables, figures and the regressions described in this paper may be available for designers and engineers to understand the characteristics of an embankment materials in Yeongnam region.

• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.1
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• pp.71-88
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• 2003

The DRASTIC system is widely used for assessing regional groundwater pollution susceptibility by using hydrogeological factors such as depth to water, net recharge, aquifer media, soil media, topography, vadose zone media, hydraulic conductivity. This study is providing Modified Drastic Model to which lineament density, land use, influence of groundwater drawdown caused by tunnel excavation are added as additional factors using geographic information system, and then to evaluate groundwater contamination potential of ${\bigcirc}{\bigcirc}$ area. For statistical analysis, vector coverage per each factor is converted to grid layer and after each correlation coefficient between factors, covariance, variance, eigenvalue and eigenvector by principal component analysis of 3 direction, are calculated, correlation between factors is analyzed. Also after correlation coefficients between general DRASTIC layer and rated lineament density layer, between general DRASTIC layer and rated land use layer, between general DRASTIC layer and rated tunnel excavation influence layer are calculated, final modified DRASTIC model is constructed by using them with each weighting. When modified DRASTIC model was compared with general DRASTIC model, contamination potential in modified DRASTIC model is fairly detailed and consequently, vulnerable area which has high contamination potential could be presented concretly.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.785-789
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• 2012

Background and Purpose: Cisplatin is the most common chemotherapeutic agent for loco-regionally advanced nasopharyngeal carcinoma (NPC); however, toxicity is a limiting factor for some patients. We retrospectively compared the efficacy and toxicity of weekly docetaxel-based and cisplatin-based concurrent chemoradiotherapy in loco-regionally advanced NPC. Methods and Materials: Eighty-four patients with Stage III and IVA-B NPCs, treated between 2007 and 2008, were retrospectively analyzed. Thirty received weekly docetaxel-based concurrent chemotherapy, and 43 were given weekly cisplatin-based concurrent chemotherapy. Radiotherapy was administered using a conventional technique (seven weeks, 2.0 Gy per fraction, total dose 70-74 Gy) with 6-8 Gy boosts for some patients with locally advanced disease. Results: Median follow-up time was 42.3 months (range, 8.6-50.8 months). There were no significant differences in the 3-year loco-regional failure-free survival (85.6% vs. 92.3%; p=0.264), distant failure-free survival (87.0% vs. 92.5%; p=0.171), progression-free survival (85.7% vs. 88.4%; p=0.411) or overall survival (86.5% vs. 92.5%, p=0.298) of patients treated concurrently with docetaxel or cisplatin. Severe toxicity was not common in either group. Conclusions: Weekly docetaxel-based concurrent chemoradiotherapy is potentially effective and has a tolerable toxicity; however, further investigations are required to determine if docetaxel is superior to cisplatin for advanced stage NPC.

• Journal of Wetlands Research
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• v.19 no.2
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• pp.223-229
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• 2017

This study analyzed the relationship between environmental factors and the temporal changes of the bird populations during the every January from 1999 to 2016 (18 years) in Donglim reservoir. 'Winter Waterbird Census of Korea' data by National Institute of Biological Resources were used for the bird population data, and principal component analysis and cluster analysis were used to analyze the changes of annual population. The average temperature of January and the average storage rate of the reservoir were used as environmental factors. According to the results of the study, the population changes in the study area can be explained by the increase and decrease of two water bird groups and a mountain bird group. The average temperature of the years when the population of water bird groups increased was more than $1.4^{\circ}C$ in comparison with the year when mountain birds increased. On the other hand, the influence of the water content was not clear. The visiting of Baikal Teal affected by temperature was a factor affecting the other group of water bird and a mountain bird group. The results of this study suggest that the temperature change affects the global spatial distribution of birds and the migration of large population species such as Baikal Teal affects species composition and populations of birds at local scale. Therefore, understanding of environmental changes at large scale and spatial distribution of species and flock contributes to understand the temporal variation of the bird population at regional or local scales.

• Journal of the Korea Institute of Building Construction
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• v.9 no.6
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• pp.79-89
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• 2009

More and more domestic skyscrapers have been rapidly constructed to get enough living space for people living in overcrowded cities. The purpose of skyscrapers is to provide citizens with useful facilities and to establish landmarks and also national and regional symbols. Previous studies have been conducted which focused on the structure, materials, plans, maintenance, and relevant information regarding skyscrapers. Skyscrapers, however, are different from other smaller buildings regarding the residential environment as well as in other ways. Recently, several problems have been raised in that the indiscreetness of current skyscrapers cannot guarantee residents a high quality living environment, and they might contain risks unless criteria are put forward to ensure that the design and facilities provide for this aim. It is judged that a set of performance criteria for the residential environment to ensurethe residents' quality of life could solve this problem. This study therefore aims to suggest a method for the improvement of the residential environment of skyscrapers by establishing residential environment evaluation factors. In conclusion, this study calculates the weight of each evaluation factor using AHP (an analytic hierarchy process) and suggests evaluating criteria. It is expected that this study could be used to propose guidelines for residents at the design and planning stage of building a skyscraper.

• Korean Chemical Engineering Research
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• v.45 no.5
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• pp.523-528
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• 2007

The objectives of this research are to investigate the mechanism of coagulation affecting UF, find out the effect of metal salt coagulant on membrane fouling. Either rapid mixing + UF or slow mixing + UF process caused much less flux decline. For PACl coagulant, the rate of flux decline was reduced for both hydrophilic and hydrophobic membrane than alum due to higher formation of flocs. In addition, the rate of flux decline for the hydrophobic membrane was significantly greater than for the hydrophilic membrane, regardless of pretreatment conditions. In general, Coagulation pretreatment significantly reduced the fouling of the hydrophilic membrane, but did little decrease the flux reduction of the hydrophobic membrane. When an Al(III) salt is added to water, monomers, polymers, or solid precipitates may form. Different Al(III) coagulants (alum and PACl) show to have different Al species distribution over a rapid mixing condition. During the rapid mixing period, for alum, formation of dissolved Al(III) (monomer and polymer) increases, but for PACl, precipitates of $Al(OH)_{3(s)}$ increases rapidly. This experimental results pointed out that precipitates of $Al(OH)_{3(s)}$ rather than dissolved Al(III) formation is major factor affecting flux decline for the membrane.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5476-5487
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• 2013

From foreign and/or domestic investors' perspectives, it may be interesting to find any financial attributes or profile of the firms headquartered in 'Chungcheong' province concerning profitability, given that this subject so far drew less attention in the previous literature. This study performed three hypothesis tests on the profitability indicator by utilizing the models such as the 'panel data' one and the 'logistic' regression one, applying a modified 'Dupont' system. With respect to the major findings, the results identified that the proxies measuring leverage across the book-value(BVLEV1) and the market-value(MVLEV1) bases, were statistically significant constituents determining profitability. Another explanatory variable, SIZE, with its positive and statistically significant relationship to the indicator, represented that the firms in the province were smaller than their counterparts in the other regional areas in Korea. DRELY applying a modified 'Dupont' system, found to be the only statistically significant discriminating factor between these comparison groups. As one of the primary contributions of this study, the outcomes may be used by the financial institutions operated across the regions including Seoul Metropolitan area, when implementing their lending practices to provide funds for potential borrowers such as the firms belonging to 'Chungcheong' province.