• Korean Journal of Digital Imaging in Medicine
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• v.14 no.2
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• pp.39-46
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• 2012

Purpose : The purpose of this study was to reduce Entrance Surface Dose and maintain image quality by changing Source to Image receptor Distance. And we'd like to compare ESD on this study to DRLs in other contries. Materials and Methods : We used indirect DR system(Definium 8000, General Electric, USA)and phantom(ART-200X, Flukebiomedical, USA),glass dosimeters(GD-352M, Asahi Techno Glass, Japan)for this study. The imagies were obtained throuh 80kVp fixed, and different tube currents using AEC mode in $16{\times}16$(inch) field size and changing Source to Image receptor Distance from 100 cm to 130 cm per 10 cm unit. The phantom with attaching 5 glass dosimeters on abdomonal skin was set at supine and erect position as a anterioposterial projection on detector For measuring Entrance Surface Dose. Image analysis was conducted by histograms of Image J(1.46r) which was given from National Institutes of Health(NIH). Results : Due to inverse square law of distance, the tube currents were increasing 42.6 % in supine position and 32.6 % in erect position according to the change of Source to Image receptor Distance. While Entrance Surface Doses were rapidly decreasing 14.2 % in supine position and 29.4 % in erect position according to the change of Source to Image receptor Distance. As the results of histogram using Image J, pixel mean values from 100 cm to 110 cm, 120 cm and 130 cm were decreasing each 1.4%, 2.5%, 2.7%, 4.5%, 2.2 %, 5.8 % in supine, erect position. While standard deviations from 100 cm to 110 cm, 120 cm and 130 cm were increasing each 1.4 %, 2.5 %, 2.5 %, 4.0 %, 2.0 %, 4.9 % Consequently, there are no significant differences in abdomen images taken. Conclusion: As the results described above, we strongly recommend using long Sourceto Image receptor Distance than 100cm that we have been using. So, we should deliver less Entrance Surface Dose to the patients while maintaining image quality in abdomen radiography.

• Journal of Gifted/Talented Education
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• v.26 no.1
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• pp.1-20
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• 2016

This study explored the cognitive characteristics and learning needs of economically disadvantaged gifted students. Gifted students(n=99), economically disadvantaged gifted students(n=43), and non-gifted students(n=50) participated in intelligence and creativity tests, and took self assessments of meta-cognition, epistemological beliefs, learning style preferences, and personal time usage. Superior abstract reasoning ability of economically disadvantaged gifted students was found because their scores on Raven's Test had risen rapidly compared to the other groups. Economically disadvantaged gifted students showed similar high scores as the gifted student on the Torrance Tests of Creativity Thinking-Figural, but not on Verbal. They were found to have a perception of the positive relationships among effort, learning abilities, and values of learning integrated knowledge with a general plan. However, they showed lower meta-cognitive control abilities than the gifted students in learning management and strategies, epistemological beliefs in value of rational operations, and time usage for learning. It is necessary to assign economically disadvantaged gifted students a task with various step by step methods of approach because these students prefer a new and creative task to difficult ones. Instruction plans such as developing language and meta-cognitive abilities and practical application of learning content was proposed.

• Korean Journal of Medicinal Crop Science
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• v.23 no.3
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• pp.185-189
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• 2015

In this study, the clinical safety and toxicology of oral ingestion of supplement capsules containing ginseng radix was investigated in healthy young volunteers. This study was a pilot randomized, double blinded, placebo controlled trial. The healthy volunteers were divided into 6 groups of 20 each (10 males and 10 females). They took the ginseng powder for 35 days (3g/day) for safety evaluation. There were measured general healthy levels such as hematological, biochemical and electrocardiographic parameters. After the first week, besides Korean white ginseng the other treatments led to an significant increase of white blood cells. Korean red ginseng increased UREA (blood urea nitrogen) in healthy volunteers, but it didn't exceed the range of normal values, and in the subsequent process of treatment there is no effect of elevating UREA. After the three weeks, Korean white ginseng showed relatively low the content of blood glucose and low-density lipoprotein cholesterol. After the five weeks, compared with the other treatments, Korean red ginseng increased white blood cells, platelet distribution width and average volume of platelet. Korean white ginseng decreased low-density lipoprotein cholesterol. American ginseng decreased blood creatinine in healthy volunteers. In conclusion, through test the blood routine, urine routine, liver function, renal function, blood glucose, blood lipid and electrocardiogram, the healthy volunteers continuous taking ginseng for 35 days (3 g/day) is safe and reliable, and have no obvious adverse reactions and side effects.

• Environmental and Resource Economics Review
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• v.14 no.3
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• pp.699-728
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• 2005

This article is basically an extension of Barten(1993), Brown et al. (1995), Holt and Bishop's(2002) price formation system. A new dynamic price formation system is attempted considering full rationality of the consumers' side. The underlying idea of the new dynamic price formation system is that consumers are rational and farsighted and thus consider past and future consumptions in addition to current consumption to accept the prices traders called. In an empirical application, the U.S. commercial fish demand data are particularly interesting to this analysis in which the species are over fished, including many of the most valuable species. Especially, the grouper-snapper complex are under management jurisdiction of the National Marine Fisheries Council. In the empirical section, it shows how to adapt the model to estimate the marginal values to consumers of commercial fisheries. Since it is conceived of regulations as inducing movements along the marginal value curves, it is of growing importance to regional and national policy makers who are confronted with competing claims on diminishing fish stocks by commercial fisheries interests. It performs well and shows the plausible signs and magnitudes of price flexibilities and interaction among species. It further contributes to the general methodology of applied economics.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.3 no.1
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• pp.1-6
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• 1970

A series of experiments have been made on the mass culture of Phaeodactylum tricornutum, Platymonas sp. and Chlorella sp. in the laboratory. The shortest lag phase was found In the culture of Ph. tricornutum followed by Platymonas sp. and Chlorella sp. As compared to the aeration culture, the stagnant culture, in general, showed long duration of the lag phase, short period of the exponential phase and extremely small daily increment. The relative growth constants of Ph. tricornutum, Chlorella sp. and Platymonas sp. were $0.302{\pm}0.028$, $0.226{\pm}0.013$, and $0.151{\pm}0.008$, respectively The maximum daily increment of the three species and then daily ages are as follows: Ph. tricornutum Maximum daily increment : 47.5, Daily age : 10, Platymonas sp. Maximum daily increment : 5.6, Daily age : 14, Chlorella sp. Maximum daily increment : 21.1, Daily age : 14 Comparing the packed cell volume with a certain number of cells, the largest value was found in the population of Ph. tricornutum followed by Platymenas sp. and Chlorella sp. A straight line relationship exists between the two values, and the magnitude of the relationship coincides well with the size of the cells. The culture of Ph. tricornutum was proved satisfactory for feeding the larvae of bivalves at about 12 days after innoculation and both of Platymenas sp. and Chlorella sp. were about 16 days respectively.

• Journal of Convergence for Information Technology
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• v.10 no.11
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• pp.340-350
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• 2020

This study was conducted to present comprehensive professionalism measurement tools suitable for hospital administration staffs. The study used measurement tools related to the psychological and behavioral characteristics of individuals used in prior studies for administration staffs at general hospitals and hospitals. Factor analysis and reliability analysis were conducted to verify the validity and internal relevance. As a result of the analysis, it was concluded that composed of 5 factors, and that the total reliability was 94.4%, which was very reasonable as a comprehensive professionalism measurement tool. Therefore, each component was defined as Confidence of Job performance, Salary Adequacy, Pride in Duties, Ability to achieve work goals, and Work Autonomy in order to provide a clear meaning. Professionalism from a modern perspective is a broader concept than traditional professionalism, including the subjective perceptions of job values and individuals' their abilities. Therefore, comprehensive professionalism measurement tools presented in this study will be very suitable and useful for hospital administration staffs.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.173-183
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• 2016

The purpose of this study is to see how a CEO's ethics affects each company's business performance, as the ethical management of global companies are being one of the social issues at this time, particularly in construction companies. The survey was conducted amongst the engineers and managers who are currently engaged in domestic major companies as well as small businesses, and analyzed based on the frequency, reliability, factor, and multiple regression method. The results are as follows by use of SPSS 20 as a statistical analysis tool. CEO's ethics has a positive effect on financial performance, business ethics, organizational achievement, social achievement. The study found that the higher ethical sense a CEO has, which is one of the highest values of CEO, the higher ownership an employee has, and the more a CEO has a communication with the employees, the more credibility is mutually built, which will be a driving force of company's development. This study needs more wide study for on the effect of CEO's ethics on the business performance of general company in the future.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.939-946
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• 2010

The purpose of this study was to enhance the quality of gochujang sauces containing Salicornia herbacea L. extracts at concentrations of 0%(C), 1%(RS-1), 2%(RS-2), and 3%(RS-3). Free sugars detected in gochujang sauce were sucrose, glucose, maltose, and fructose. pH level was not significantly different among the samples. As the contents of S. herbacea L. extracts increased, the salinity decreased. The colors of the gochujang sauce as indicated by -L, $a^{\ast\ast\ast}$, and $b^{\ast}$ values decreased as contents of gochujang sauce S. herbacea L. extracts increased. Most of the mineral contents of gochujang sauce containing S. herbacea L. extracts were higher than that of control. Overall acceptabilities of the S. herbacea L. extracts-added groups were in the order of 2%, 3%, 0%, and 1%. The 2% (RS-2) S. herbacea L. extract-added group was highly rated in general charateristics, making it the most desirable for making S. herbacea L. extract-added gochujang sauce.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.1 s.47
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• pp.17-23
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• 2006

The research on strong ground motions became important recently due to more severe requirement of seismic design for the domestic buildings and structures. The empirical Green's function method, which uses similarities between small and large earthquakes, was applied to make synthetic ground motions. That method was applied to the 2 earthquakes which occurred sequently in time within narrow area in Japan. The strong ground motions for the virtual earthquake (magnitude 6.5) were synthesized using those observed from the magnitude 4.7 earthquake. Then, the synthesized ground motions (acceleration, velocity, and displacement) were compared to those observed from real earthquake (magnitude 6.5). The results showed that the general shapes of waveforms in time domain and the Fourier spectrum In frequency domain from synthesized ground motions (acceleration, velocity, and displacement) are similar to the observed strong ground motions within acceptable degree. The peak values of 3 kinds of synthesized strong ground motions in time domain are comparable between the synthesized and the real strong ground motions, especially only about 9% difference in acceleration peak value.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.4
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• pp.31-37
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• 2008

Conventional cooperative communications can attain gain of spatial diversity and path loss reduction because destination node independently received same signal from source node and relay node located between source node and destination node. However, these techniques bring about decreased spectral efficiency with relay node and increased complexity of receiver by using maximal ratio combining (MRC). This paper has proposed cooperative ARQ protocol that can improve the above problems and can get the better performance. This method can increase the spectral efficiency than conventional cooperative communication because if the received signal from source node is satisfied by the destination preferentially, the destination transmits ACK message to both relay node and source node and then recovers the received signal. In addition, if ARQ message indicates NACK relay node operates selective retransmission and we can increase reliability of system compared with that of general ARQ protocol in which source node retransmits data. In the proposed protocol, the selective retransmission and ARQ message are to be determined by comparing log-likelihood ratio (LLR) computation of received signal from source node with predetermined threshold values. Therefore, this protocol don't waste redundant bandwidth with CRC code and can reduce complexity of receiver without MRC. We verified spectral efficiency and BER performance for the proposed protocol through Monte-Carlo simulation over Rayleigh fading plus AWGN.