• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5145-5151
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• 2013

Background: Numerous carcinogens and reactive oxygen species (ROS) may cause DNA damage including oxidative base lesions that lead to risk of nasopharyngeal carcinoma. Genetic susceptibility has been reported to play a key role in the development of this disease. The base excision repair (BER) pathway can effectively remove oxidative lesions, maintaining genomic stability and normal expression, with X-ray repair crosscomplementing1 (XRCC1), 8-oxoguanine glycosylase-1 (OGG1) and apurinic/apyimidinic endonuclease 1 (APE1) playing important roles. Aims: To analyze polymorphisms of DNA BER genes (OOG1, XRCC1 and APE1) and explore their associations, and the combined effects of these variants, with risk of nasopharyngeal carcinoma. Materials and Methods: We detected SNPs of XRCC1 (Arg399Gln), OGG1 (Ser326Cys), APE1 (Asp148Glu and -141T/G) using the polymerase chain reaction (PCR) with peripheral blood samples from 231 patients with NPC and 300 healthy people, furtherly analyzing their relations with the risk of NPC in multivariate logistic regression models. Results: After adjustment for sex and age, individuals with the XRCC1 399Gln/Gln (OR=1.96; 95%CI:1.02-3.78; p=0.04) and Arg/Gln (OR=1.87; 95%CI:1.29-2.71; p=0.001) genotype variants demonstrated a significantly increased risk of nasopharyngeal carcinoma compared with those having the wild-type Arg/Arg genotype. APE1-141G/G was associated with a significantly reduced risk of NPC (OR=0.40;95%CI:0.18-0.89) in the smoking group. The OR calculated for the combination of XRCC1 399Gln and APE1 148Gln, two homozygous variants, was significantly additive for all cases (OR=2.09; 95% CI: 1.27-3.47; p=0.004). Conclusion: This is the first study to focus on the association between DNA base-excision repair genes (XRCC1, OGG1 and APE1) polymorphism and NPC risk. The XRCC1 Arg399Gln variant genotype is associated with an increased risk of NPC. APE1-141G/G may decrease risk of NPC in current smokers. The combined effects of polymorphisms within BER genes of XRCC1 399Gln and APE1 148Gln may contribute to a high risk of nasopharyngeal carcinoma.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.27-36
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• 2015

The purpose of this study was to investigate the influence relationships among individual career orientation, preparation of old age, social networks, and the entrepreneurial intention of the potential entrepreneurs. 408 numbers of structured questionnaire were collected from the potential entrepreneurs who live in Seoul through the online Google survey method and offline face to face method. And the collected data was analyzed on frequency analysis, validity analysis, t-test, ANOVA, and regression analysis etc. using the SPSS WIN 21.0 program. The results are as follows. Firstly, innovation, entrepreneurial creativity, and autonomy orientation affect on entrepreneurial intention positively(+), but security orientation has a negative(-) effect on entrepreneurial intention in the influence relationships between individual career orientation and entrepreneurial intention. Secondly, economical and emotional preparation have positive(+) influences on entrepreneurial intention in the influence relationships between individual career orientation and entrepreneurial intention. Thirdly, the sub-variables of social networks, that is, assist and role models exert a positive(+) influence on entrepreneurial intention in the influence relationships between social networks and entrepreneurial intention. Fourthly, social networks plays a moderating role only on the relationship between security orientation and entrepreneurial intention in the analysis about the moderating effects of social networks on the influence relationships among individual career orientation, preparation of old age, and entrepreneurial intention. Fifth, a social network of relationships to help prepare the old establishment has been found to help regulate effective analysis of whether or not the results of adjustment.

• Management & Information Systems Review
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• v.37 no.3
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• pp.115-130
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• 2018

The purpose of this study is to clarify the relationship between organizational characteristics and information systems characteristics or job satisfaction, attempts to examine the regulatory effects brought about by the adjustment of social capital theory. So far, The results of this study are based on the analysis of individual models from the perspectives of each functional organization such as HR, organization, finance, operation, and MIS. Therefore, this paper attempted a comprehensive analysis of factors affecting job satisfaction and firm performance by presenting an integrated research model of organizational perspectives in addition to the approach of MIS perspective. The characteristics of information system were promptness, CEO support, and compensation. And the organizational characteristics were multiple regression analysis using innovation, trust, and preferential factors. The analysis data is based on sixth data from the HCCP of Korea Productivity Center. According to the analysis results, all the variables had a significant influence on satisfaction, especially CEO support and trust. The analysis of the moderating effect between innovation and job satisfaction was moderated by vision sharing. Only the logistic regression analysis of the satisfaction with the average salary of the members among the demographic variables was statistically significant. Therefore, this study can be concluded that the overall satisfaction level will be improved by recognizing appropriate compensation as sufficient compensation.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.233-244
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• 2012

The Korea Astronomy and Space Science Institute and the Department of Astronomy at the University of Texas at Austin are developing a near infrared wide-band high resolution spectrograph, immersion grating infrared spectrometer (IGRINS). The compact white-pupil design of the instrument optics uses seven cryogenic mirrors, including three aspherical off-axis collimators and four flat fold mirrors. In this study, we introduce the optomechanical mount designs of three off-axis collimating mirrors and one flat slit-viewer fold mirror. Two of the off-axis collimators are serving as H and K-band pupil transfer mirrors, and are designed as system alignment compensators in combination with the H2RG focal plane array detectors in each channel. For this reason, the mount designs include tip-tilt and parallel translation adjustment mechanisms to properly perform the precision alignment function. This means that the off-axis mirrors' optomechanical mount designs are among the most sensitive tasks in all IGRINS system hardware. The other flat fold mirror is designed within its very limitedly allowed work space. This slit-viewer fold mirror is mounted with its own version of the six-point kinematic optics mount. The design work consists of a computer-aided 3D modeling and finite element analysis (FEA) technique to optimize the structural stability and the thermal behavior of the mount models. From the structural and thermal FEA studies, we conclude that the four IGRINS mirror mounts are well designed to meet all optical stability tolerances and system thermal requirements.

• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.763-771
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• 2013

Due to a decrease in the number of college prep students which was triggered by the low birth rate since 1990, it is predicted, beginning 2016, that the entrance quota for colleges will exceed the number of applicants for college admissions. This serious imbalance between supply and demand raises serious problems for the regional universities, many of which have already been struggling to recruit new students and even considered closing down the schools. In an effort to securing best high school students, many of the schools have been developing various unique and specialized selectional processes for the applicants. In this research, through a statistical analysis of special admission processes for vocational high school students who were admitted to a regional state-run university (University A), I tried to find a way to effectively deal with the student management. Statistically analyzing these first-year students' enrollment and their adjustment processes as well as the departmental relationships and gender differences, I tried to find some better ways to secure good applicants. It is expected that this study will not only be utilized as guide to adopt a way to bypass the enrollment quota in order to secure talented students but also be served as a reference that will help the students adapt themselves to school life until they graduate. It is also expected that this study will be expanded in such a way as to compare it with other models and even develop a new type of college entrance system that would fit future college admission policies.

• Journal of Korea Port Economic Association
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• v.28 no.3
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• pp.111-125
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• 2012

This study investigates the behavioral characteristic difference of the container volumes of three ports-Gwangyang, Incheon, and Pyeongtaek-Dangjin. All series span the period January 2003 to December 2011. I first test whether the series are stationary or not. I can reject the null hypothesis of a unit root in each of the level variables and of a unit root for the residuals from the cointegration at the 5 percent significance level. I hitherto make use of error-correction model and find that Gwangyang port is the slowest in adjusting the short-run disequilibrium, whereas the adjustment speed of Incheon is much faster than that of Gwangyang. The impulse response functions indicate that container volumes increase only a little to the negative shocks in exchange rate, while they respond positively to the shocks in the business activity in a great magnitude and decay very slowly to its pre-shock level. meaning that the shocks last very long. The accumulative response to the exchange rate increase of 20 won per dollar and the 5 point industrial production increase is the smallest in Gwangyang, no more than a half of that of two ports. The intervention-ARIMA models also forecast that Gwangyang port will have much lower growth rate than Incheon and Pyeongtaek-Dangjin port in trading volumes.

• The Korean Journal of Financial Management
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• v.7 no.1
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• pp.1-20
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• 1990

In most of studies on market efficiency, the stability of risk measures and the normality of residuals unexplained by the pricing model are presumed. This paper re-examines stock splits, taking the possible violation of two assumptions into accounts. The results does not change the previous studies. But, the size of excess returns during the 2-week period before announcements decreases by 43%. The results also support that betas change around announcements and the serial autocorrelation of residuals is caused by events. Based on the results, the existing excess returns are most likely explained as a compensation to old shareholders for unwanted risk increases in their portfolio, or by uses of incorrect betas in testing models. In addition, the model suggested in the paper provides a measure for the speed of adjustment of the market to the new information arrival and the intensity of information contents.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.801-806
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• 2018

Germanium crystals have a dead layer that causes efficiency deterioration because the layer is not useful for detection but strongly weakens the photons. Thus, when the data provided by the manufacturer is used in the detector simulation model, there is a slight difference between the calculated efficiency and the measured efficiency.The shape and dimensions of the high purity germanium (HPGe) detector were determined by CT scans to accurately characterize the shape for the Monte Carlo roll simulation. It is found that the adjustment of the dead layer is a good match with the relative deviation of ${\pm}3%$ between the measurement efficiency and the simulation efficiency at the energy range of 50 - 1500 keV. Simulation data were compared by varying the thickness of the dead layer. The new Monte Carlo simulations were compared with the experimental results to obtain new blank layer thicknesses. The difference in dead layer results for the 1.5 mm thick end cap simulation model in 1.4 and 1.6 mm thick End Cap simulation models was a systematic error due to the accuracy of the end cap dimensions. After considering all errors including statistical errors and systematic errors, the thickness of the detector was calculated as $1.02{\pm}0.14mm$. Therefore, it was confirmed that the increase in the thickness of the dead layer causes the effect to be effected on the efficiency reduction.

• Journal of The Korean Association For Science Education
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• v.39 no.2
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• pp.173-186
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• 2019

The purpose of this study is to design and apply a pilot inquiry experiment focusing on the epistemological issues of scientific activities, and derive educational implications by analyzing experimental activities and reflective discussions. Three graduate students who major in science education participated in the study voluntarily. Participants showed the characteristics of stable enquiry in Experiment 1. However, the small but continuous changes in Experiment 2 led the experiment to a phase of fluid enquiry seeking new theories. Participants mobilized various resources, proposed new hypotheses, and models and requested additional experiments to verify them. In the process of reflective discussions, the participants led to the following three epistemological issues. First, at the beginning of the experiment, their observations were theoretically dependent. Second, when the observations were no longer coherent with theory, they face a crisis, and the adjustment of observation and theory proceeds. Third, stable enquiry and fluid enquiry are performed according to the relationship between observation and theory. The educational implications of school science inquiry based on the above process and results are as follows: First, this study shows that fluid enquiry can follow stable enquiry naturally, and examples of the activities are presented together. Second, in this study, it was confirmed that participants could draw up epistemological issues based on their experiences through reflective discussions following inquiry.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1393-1405
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• 2020

UAV (Unmanned Aerial Vehicle) can acquire high-resolution images due to low-altitude flight, and it can be photographed at any time. Therefore, the UAV images can be updated at any time in map production. Due to these advantages, studies on the possibility of producing large-scale digital maps using UAV images are actively being conducted. Precise digital maps can be used as base data for digital twins or smart cites. For producing a precise digital map, precise sensor modeling using GCPs (Ground Control Points) must be preceded. In this study, geometric models of UAV images were established through a precision sensor modeling algorithm developed in house. Then, a digital map by stereo plotting was produced to evaluate the possibility of large-scale digital map. For this study, images and GCPs were acquired for Ganseok-dong, Incheon and Yeouido, Seoul. As a result of precision sensor modeling accuracy analysis, high accuracy was confirmed within 3 pixels of the average error of the checkpoints and 4 pixels of the RMSE was confirmed for the two study regions. As a result of the mapping accuracy analysis, it satisfied the 1:1,000 mapping accuracy announced by the NGII (National Geographic information Institute). Therefore, the precision sensor modeling technology suggested the possibility of producing a 1:1,000 large-scale digital map by UAV images.