• Journal of the Korean association of regional geographers
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• v.3 no.1
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• pp.35-50
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• 1997

The purpose of this research seeks to analyze the spatial variations in the sex age structure which have been shown to exist within the study atrea, the Kyonggi province in Korea. In this study it is desired to use the Age Structure Index developed by Coulson in order to describe thi sex age structure of each of 186 tracts that comprise the tracted portion of the Kyonggi province. The mechanics of computing the Age Structure Index are found in the equation describing a linear least squares trend line: y=a+bx. For each census tract, the percentage of the population in each age group(y) was plotted against the middle age of each age group(x). The a is a constant representing the value of y, when x equals zero. The b is the regression coefficient and is a measure of the angle of the slope of the least squares trend line. Thus the value of b is the Age Structure Index for each census tract. The major results of this investigation can be summarized as follows: The spatial distributions of sex age structures in the Kyonggi province are far from random. They have exhibited great regularity with the yonger sex age structures near Seoul and a sharp decline to the older sex age structures out in all derections towards rural region. The results of this investigation should have important general significance for the study of the Kyonggi province Age Structure Index is a flexible, operational definition shich allows sex age structure to be measured, mapped, and incorporated in a wide variety of methods of statistical analysis. Futurer, it has been demonstrated that sex age structure varies spatially within Seoul metropolitan finge and that this variation is relagfed to many other attributes of the population. Especially, Age Structure Index is strongly related to the variables-rate of population growth rate. density, rate of numbers of manufacturing, land price. At the same time, considerably more research is needed before a genmeral body of knowlege concerning sex age structure can be developed.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.10
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• pp.1-10
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• 2021

This paper attempts to investigate the determinants of capital structure of Vietnamese firms and also shed light on some of the factors of the modern theory of capital structure which is relevant for explaining the capital structure in advanced countries which are also relevant in the context of Vietnam. Using panel data from more than 1000 Vietnamese listed enterprises census 2017-2020, the paper finds that leverage ratio of Vietnamese firms is significantly related to probability. The firms have high level of fixed assets which they use as collateral, resulting in higher debt ratio, which is in line with the pecking order theory. The result also confirm that highly targeted debt ratio is positively correlated with the industry characteristics (using real estate firms as a benchmark), in which firm operates. Furthermore, consistent with the trade-off hypothesis, the leverage ratio is positively affected by non - debt tax shield. The result confirms that a large number of companies are state - owned, will have an insignificant impact of firm's size (as reverse proxy for bankruptcy cost) on leverage ratio. We also find that there is no distinction between state-owned enterprises and private enterprises due to strict adherence to the rules set by the Vietnamese government. Distinct from other countries, corporate income tax has slight impact on capital structure in Vietnamese firms.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.35.2-35.2
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• 2016

We present a census of AGN-driven gas outflows based on the kinematics of ionized gas and stars, using a large sample of ~11,000 emission line galaxies at z < 0.3, selected from SDSS. First, a broad correlation between gas and stellar velocity dispersions indicates that the bulge gravitational potential plays a main role in determining the ionized gas kinematics. However, the velocity dispersion of the [OIII] emission line is larger than stellar velocity dispersion by a factor of 1.3-1.4, suggesting that the non-gravitational (non-virial) component, i.e., outflows, is almost comparable to the gravitational component. Second, gas-to-stellar velocity dispersion ratio increases with both AGN luminosity and Eddington ratio, suggesting that non-gravitational kinematics are clearly linked to AGN accretion. The distribution in the [OIII] velocity - velocity dispersion diagram dramatically expands toward large values with increasing AGN luminosity, implying that the launching velocity of gas outflows increases with AGN luminosity. Third, the fraction of AGNs with a signature of the non-gravitational kinematics, steeply increases with AGN luminosity and Eddington ratio, while the majority of luminous AGNs presents the non-gravitational kinematics in the [OIII] profile. These results suggest that ionized gas outflows are prevalent among type 2 AGNs. On the other hand, we find no strong trend of the [OIII] kinematics with radio luminosity, once we remove the effect of the bulge gravitational potential, indicating that ionized gas outflows are not directly related to radio activity for the majority of type 2 AGNs. We will discuss the implication of these results for AGN feedback in the local universe.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.1-8
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• 2003

This study was conducted to investigate the effects of road on bird community by line transect census method from May 2000 to January 2001 in Mt. Geumsan, Namhae-Gun, Kyeongsangnam-do. Canopy layer was more developed in forest area than road area. Understory vegetation of road area was more developed than forest area. Twenty six and twenty three bird species were observed in road and forest area, respectively, White's thrush and ashy minivet were observed just only in forest area, and Siberian blue robin, blue-and-white flycatcher and gold crest were in road area. The birds being to bush nesting and foraging guilds in road area were more than forest area. It is known that the road construction was negatively affected on bird community. However, road construction would be not so negative on bird community according to the results of thie study. It would be needed the maintenance of upper canopy layer and understory vegetation to reduce negative effect of road on bird communities in forest area.

• Journal of Korea Multimedia Society
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• v.15 no.10
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• pp.1247-1256
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• 2012

There are many filter based image processing algorithms and they usually require a huge amount of computations and memory accesses making it hard to attain a real-time performance, expecially in embedded applications. In this paper, we propose a pipelined hardware structure of the filter based face detection algorithm to show that the real time performance can be achieved by hardware design. In our design, the whole computation is divided into three pipeline stages: resizing the image (Resize), Transforming the image (ICT), and finding candidate area (Find Candidate). Each stage is optimized by considering the parallelism of the computation to reduce the number of cycles and utilizing the line memory to minimize the memory accesses. The resulting hardware uses 507 KB internal SRAM and occupies 9,039 LUTs when synthesized and configured on Xilinx Virtex5LX330 FPGA. It can operate at maximum 165MHz clock, giving the performance of 108 frame/sec, while detecting up to 20 faces.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.2
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• pp.139-147
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• 2010

This study monitored a variety of marine fish communities in artificial reefs unit of the total 5 types (Dice type, Octagonal turtle type, Two-stage tube type, Gazebo type, Tetrapod type) which are located in the marine ranching at Jeju island by scuba diving in May, July, October and December 2009. Underwater photographing was accomplished at total 3 phases (condition of artificial reefs photographing, concentric circle movement photographing and line transect photographing). The preservation condition of artificial reefs facility was very good, and the dominant species were Chromis notatus, Sebastes thompsoni, Oplegnathus fasciatus and Halichoeres poecilopterus. Fish abundance was high in May and June, and low in October and December, 2009. Chromis notatus was dominant at the all types of artificial reefs, Halichoeres poecilopterus for Gazebo type and Tetrapod type of artificial reefs, and Sebastes thompsoni for Dice type, Octagonal turtle type and Two-stage tube type of artificial reefs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.411-417
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• 2017

It is necessary to determine the current and future energy consumption by farm households for the rational specification of energy related policy in the Korean agricultural sector. Especially, It is important to identify the consumption by source of energy and by the crops. On the other hand, the world has tried to reduce the production of greenhouse gases and, in line with this, the Korean government established related legislations to contribute to this reduction (30% reduction in emissionsby 2020). The reduction target of the agricultural sector is specified as 5.2% of the national total. This study focuses on sampling design to determine the energy consumption and emission of greenhouse gases, and suggests several alternatives to improve the confidence level and to make a dent survey and estimation errors. The population for the energy consumption survey of the agricultural sector was derived from agricultural census data. In the case of commodities with high skewness, we cut the sample range to within the statistical significant range. The number of samples in each class is specified using the Neyman allocation method and 95% significance level. The estimation results are compared with the population to verify the statistical significance and several management methods of sampling errors are suggested.

• Journal of Navigation and Port Research
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• v.39 no.3
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• pp.267-275
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• 2015

Port Logistics Industry plays a crucial role in trade creating added value, and contributes greatly in economic growth of a nation. Multitude of studies have been conducted to develop this industry as a means of intensifying national competitiveness. In line with this trend, this study aims to examine the effect of the Port Logistics Industry on the regional economy focusing on Ulsan, and also compare the industry among five port cities by using Korean Standard Industrial Classification (KSIC) Rev. 9 and 2010 Economy Census. The results of this study demonstrate that the Port Logistics Industry has significant regional employment rate and economic importance, showing the high number of workers (11.7%) and sales (13.1%) in 2010. According to the comparison among five port cities between 2007 and 2011, the increase of annual average in the number of companies of Gwangyang (5.72%) and Ulsan (4.23%) is higher than the national average (1.74%), and Ulsan (23.82%) and Pyeongtaek (25.74%) show high increase of annual average in the number of workers.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.473-481
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• 2005

Objectives : We wanted to identify those factors associated with stomach, colon, breast and cervix cancer screening. Methods : A population-based telephone survey was conducted for 2 weeks (the 9th-23th of July, 2004) by trained interviewers with using a questionnaire. 2,598 respondents (females aged 30 years or over, and the males aged 40 years or over) were selected by random-digit dialing that was based on the 2000 Population and Housing Census. The data on socio-demographic, health behavior and enabling factors were collected. 2,571 respondents were included in analysis. The cancer screening rate was classified into 2 categories : the life time screening rate and the screening rate with recommendations. Results : For the 2,571 respondent s, the life time screening rate was as follows: 52.0% (Stomach), 25.3% (Colon), 55.9% (Breast) and 76.8% (Cervix). The screening rate with recommendation was as follows : 3 9.2% (Stomach), 20.6% (Colon), 42.5% (Breast) and 58.3% (Cervix). On a multiple logistic regression analysis of the life time screening, statistically significant relationships were observed for the screening intention, the health exam, the disease history, the age of the patients and the cancer screening rates. On a multiple logistic regression analysis of the screening with recommendation, statistically significant relationships were observed for the screening intention, the health exam, the age of the patients, the concern about the risk of cancer, the voluntary health insurance for cancer and the cancer screening rates. Conclusions : The results of this study suggest that the cancer screening intention, the health exam and the age of the patients are the most important factors to participate in life time cancer screening and also screening with recommendations. A positive association was also observed for the concern about the risk of cancer, the voluntary health insurance for cancer. It is hoped that this study will be a base line data for suggesting the representative cancer screening rate in Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.76-86
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• 2012

The purpose of this study is to investigate the environmental equity of the accessibility to public transportation services in the city of Daegu. The 2005 census data as well as bus stop and subway station datasets were integrated for building the GIS database. Public transportation service areas were then identified by a coverage method. Mann Whitney U test was used for statistically comparing the socioeconomic characteristics over different levels of access to the public transportation services. Both Dong-gu, Suseong-gu, Dalseo-gu, and Buk-gu located outside of the city had worse accessibility than others while Jung-gu, Seo-gu, and Nam-gu had better accessibility than others. There appeared no environmental inequity pattern in terms of the percentages of men, women, and teenagers over the city of Daegu whereas there existed some environmental inequity pattern in terms of the percentages of people above the age of 65 and people below poverty line. This environmental inequity pattern would be caused by some factors. Firstly, the lower income class has tended to reside in the declined or blighted areas far away from public transportation facilities since this class can not afford to pay expensive rents and land prices around the main roads with higher accessibility. Many old people belonging to the lower income class also reside in the declined or blighted areas. Secondly, there has been no law to locate bus stops and subway stations considering residents' socioeconomic characteristics and the spatial distribution of public transportation facilities has been not managed systematically by the city government. This research would shed insight on building the public transportation policy to locate bus stops and subway stations and to select the routes of buses and subways considering the spatial distribution of residents' socioeconomic characteristics.