• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.34.1-34.1
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• 2010

Studies suggest that activities in luminous AGNs, residing mostly in early-type galaxies, are triggered by merging. However, the observational evidence for the connection between mergers and AGN activity is not clear yet because tracer of the past merging activities such as tidal tail, shell are often too faint. To see if we can reveal the merging features with a small telescope, we observed an AGN, MARK 478, at z=0.077 with long exposure time (7550 seconds) in V filter at Maidanak observatory. Our 2-D fitting analysis shows that the host galaxy of MARK 478 has the bulge to the total luminosity ratio of 0.3. And the residual image, after subtracting point spread function (PSF), bulge and disk components, shows that the host galaxy has an arm-like feature that could be a spiral arm or a feature from minor merging. We also show that the structural parameters obtained from our 2-D fitting match well with those derived from HST image. The promising result suggests that studies of low redshift AGN host galaxies are possible with data from a small telescope. In order to allow a statistical analysis, we hope to expand our sample size in future.

• Environmental and Resource Economics Review
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• v.19 no.1
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• pp.3-21
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• 2010

By the significant structural change in 1999, a partial privatization has occurred in Korean fossil-fuel power generation sector. Under the current price scheme wholesale electricity price is dependent on output size, and hence, may not satisfy the assumption of price-taking producers. The purpose of our study is constructing the productivity change measurements of Korean power generation sector taking into account possibly imperfect competition and variable returns to scale. Our approach based on Harrison (1994) and Levinsohn (1993) derives the plant-level productivity measurements of the period between 2001 and 2007, as well as the measurements of mark-ups and returns to scale. It is shown that the mark-up size is dependent on the plants' fuel type and is decreasing over time. Allowing for imperfect competition and variable returns to scale adjusts the productivity measurements substantially.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.4
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• pp.2223-2242
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• 2019

Distance Vector-Hop (DV-Hop) algorithm is widely used in node localization. It often suffers the wormhole attack. The current researches focus on Double-Wormhole-Node-Link (DWNL) and have limited attention to Multi-Wormhole-Node-Link (MWNL). In this paper, we propose a security DV-Hop algorithm (AMLDV-Hop) to resist MWNL. Firstly, the algorithm establishes the Neighbor List (NL) in initialization phase. It uses the NL to find the suspect beacon nodes and then find the actually attacked beacon nodes by calculating the distances to other beacon nodes. The attacked beacon nodes generate and broadcast the conflict sets to distinguish the different wormhole areas. The unknown nodes take the marked beacon nodes as references and mark themselves with different numbers in the first-round marking. If the unknown nodes fail to mark themselves, they will take the marked unknown nodes as references to mark themselves in the second-round marking. The unknown nodes that still fail to be marked are semi-isolated. The results indicate that the localization error of proposed AMLDV-Hop algorithm has 112.3%, 10.2%, 41.7%, 6.9% reduction compared to the attacked DV-Hop algorithm, the Label-based DV-Hop (LBDV-Hop), the Secure Neighbor Discovery Based DV-Hop (NDDV-Hop), and the Against Wormhole DV-Hop (AWDV-Hop) algorithm.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.3
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• pp.122-129
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• 2006

We propose the Fizeau-type phase shifting interferometer(FPSI) system for the performance test of high-order aspheric lenses. The proposed system is divided into two parts : optical part and signal processing part. Those two parts are operated by a program for hardware control. We also developed an analysis program adopting the phase shifting algorithm to analyze the obtained interferograms. We can confirm that the proposed system is efficient and adequate by direct comparison with the standard criterion in Mark IV interferometric system of Zygo. The peak-to-valley and RMS values of surface errors which are used to characterize high-order aspheric lenses are 0.845 wave and 0.1871 wave, respectively. The measurement errors between the proposed system and Mark IV are less than ${\lambda}/100$ and the repeatability is also calculated at less than ${\lambda}/100$.

• Korean Journal of Community Nutrition
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• v.18 no.4
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• pp.324-332
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• 2013

The purpose of this study was to investigate middle school students' perception of environment-friendly agricultural products (EAPs) and the degree of confidence about the certification mark. Questionnaires were distributed to 444 students of 6 middle schools located in Daegu, and a total of 416 responses were used for analysis. 28.6% of the respondents were using EAPs at home, and 62.0% of respondents didn't know whether to use EAPs at home. The 6 items representing the perception of EAPs were analyzed, resulting in 2 distinct dimensions-'benefits of EAPs' and 'attitude toward EAPs'. Regarding Benefits of EAPs, the score of 'EAPs better for health' was the highest, followed by 'EAPs have higher quality', 'EAPs were better for environmental protection', respectively. The proportion of students responded that 'the amount of pesticides should be reduced gradually' was 65.5% and only 3.4% for 'current level of pesticide use is not a problem'. There were significant differences between male and female students with regard to an interest in EAPs (p < 0.05) and opinion on the use of pesticides (p < 0.05), while no significant difference was found between groups with different education level of mothers. The respondents who use EAPs at home showed significantly higher scores with attitude toward EAPs (p < 0.001), and higher response rate for 'pesticides should not be used even if the price increases' (p < 0.05). Degree of confidence about the EAPs certification mark also affected students' perception of EAPs (p < 0.001). Our results indicate the importance of education for students on EAPs to enhance students' attitude towards EAPs and improve school meal satisfaction.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2003.05a
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• pp.31-43
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• 2003

The transformation of sector system in ICT, a prominent character in sector systems, has been paid much attention in innovation theory since Information technologies and technological environment have rapidly changed. In this context, we employ US patent data and proxy variables, measuring the basic elements for analyzing SIS and its technological characteristics in order to explore how SIS is transformed. By utilizing patent analysis, it is demonstrated that technological regimes, key links and Schumpeterian patterns of innovation have transformed drastically over last 3 decades in overall ICT sector. Consequently, our research shows clear evidence that Schumpeterian patterns of innovation have shifted from Mark I to Mark II in ICT. Our study provides a glimpse picture of dynamics of SIS since 1970 in the technological level by utilizing patent analysis.

• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.115-122
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• 2011

This paper investigates the accuracy of the vehicle pre-braking speed estimated based upon measured skidding distance. Driver ordinarily takes sudden braking when urgent situation is developed in the front or when the driver is involved in an unexpected situation, and the driver may be inflicted upon an accident depending on the required stopping distance. Among factors influencing the stopping distance of vehicle such as recognition response time of driver, performance of vehicle's braking device, and state of road surface etc, pre-braking speed is seemingly the most important influencing factor. Currently, in the investigating section of traffic accidents, the state of overspeed is determined by the pre-skidding speed calculated based on the length of skid mark. In order to identify the accurate cause of the accident, it is strongly recommended that estimation of pre-braking speed should be estimated taking into account speed reduction during transient time. In this study, we propose a method for estimating more accurate exact speed information of vehicle at the time of traffic accident. The outcomes from this study potentially help better understanding of the characteristics of vehicle for traffic safety in the future.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.29-35
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• 1999

At the design of Mark III membrane type LNG tank, an analytical and experimental approach on the fatigue strengths of membrane and its welds are very important in order to assist designers and surveyors. In this study, fatigue tests of lap weld of Mark III membrane type LNG tank were carried out and cumulative damage factor was calculated in order to estimate the fatigue life by probability density function and rule methods. It contained the following tests and reviews : 1) The fatigue tests of lap weld of stainless steel according to statistical testing method recommended by JSME, 2)Preparation of S-N curve for lap welds considering the statistical properties of the results of fatigue tests. 3) Procedure for estimating the initiation life of fatigue crack of lap welds under variable loads by the rule lf classification society and probability density function, 4) Guideline for inspection of lap welds fo membrane type LNG tank.

• The Korean Journal of Rehabilitation Nursing
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• v.5 no.1
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• pp.71-85
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• 2002

The purpose of study was to find out the relation ship between health perception and health status of clinical nurses. It also identified factors that related to health perception and health status of clinical nurses. The research design was descriptive correlational study. The subjects were consisted of 289 clinical nurses at the university hospital in Pusan. The data were collected from Feb. 12th to Feb. 28th, 2001 by self reporting structured questionnaires. The instruments used for this study were health perception questionnaire developed by Ware and Cornell Medical Index modified by Nam Ho-Chang (1965) for measuring health status. The data were analyzed by SPSS/PC+ program using frequency, percentage, mean, mean mark, standard deviation, t-test, ANOVA, Scheffe test, and Pearson's correlation coefficient. The results of this study were as follows. 1. The mean score of the health perception was $94.70{\pm}8.93$(range : 29-145), which the item mean mark score was $3.27{\pm}$0.31(range 1-5). The score of subarea of the health perception was the highest score in health concern ($4.57{\pm}0.58$) and the lowest score in rejection of sick role($2.94{\pm}0.32$). 2. The mean score of the health status was $102.83{\pm}7.61$(range: 57-114), which the item mean mark score was $1.80{\pm}0.13$ (range : 1-2). The mean mark score of the physical health status was $62.55{\pm}5.35$($1.69{\pm}0.14$) and the mental health status was $40.28{\pm}3.51$($1.83{\pm}0.16$). 3. There were statistically significant difference in the score of health perception according to the presence of disease(F=4.607, P=.011), job satisfaction (F=12.242, P=.000), and job place(F=2.838, P=.038). 4. There were statistically significant difference in the score of health status according to the age(F=3.164, P=.007), presence of leisure time(F=4.308, P=.039), presence of diseases(F=3.215, P=.042), job experience(F=9.064, P=.000), job satisfaction(F=7.182, P=.001), job place (F=5.638, P=.001), job position (F=3.900, P=.021). 5. Health perception of clinical nurse was shown to be positively related to health status(r=.543, p=.000). In conclusion, health perception of clinical nurse working at the university hospital was relatively high, and health status was fine. And the more health perception was high, the more health status was high. Therefore, the health promotion program for clinical nurses, should included health perception.

• Proceedings of the Membrane Society of Korea Conference
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• 2000.10a
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• pp.3-19
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• 2000

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