• Food Science of Animal Resources
• /
• v.26 no.1
• /
• pp.121-126
• /
• 2006

Major milk proteins have considerable variane which comes from substitution and deletions in their amino arid sequences. Variants in genes that code for milk proteins, such as ${\beta}$-lactoglobulin (${\beta}-LG$) have been established as genetic markers for milk production and milk protein composition in dairy cattle. The effect of ${\beta}-LG$ variant on milk production traits, such as milk yield. fat yield, protein yield, fat percentage and protein percentage, was estimated for 482 Holstein cows in the first lactation. The ${\beta}-LG$ variants were determined by PCR-RFLP technique at the DNA level. Single trait linear model was used for the statistical analysis of the data. Results of this study indicated that ${\beta}-LG$ variants affected significantly protein yield (p<0.05) and fat percentage (p<0.05). Animals with the AA variant produced 31kg of milk protein more than animals with the BB variant. On the contrary, cows with the BB variant had fat percentage higher by 0.35 and 0.32% compared with cows with the AA and AB variants, respectively. No associations between the ${\beta}-LG$ variants and milk yield, protein percentage and fat yield were found Therefore, milk production traits could be improved through ${\beta}-LG$ typing by increasing the frequency of A variant for protein yield or the frequency of B variant for fat content in Holstein dairy cattle population.

• Journal of Broadcast Engineering
• /
• v.13 no.5
• /
• pp.612-621
• /
• 2008

Due to the various constraints such as feasible size of data payload and low transmission power, no technical specifications on the voice communication are included in the Zigbee standard. In this paper, a voice coding technique for application to the IEEE 802.15.4 standard, which is the basis of Zigbee communication, is presented. Here, both high compression and good waveform recovery are essential. To meet those requirements, a multi-stage discrete wavelet transform (DWT) block and a binary coding block consisting of two different pulse-code modulations are exploited. Theoretical analysis and simulation results in an indoor wireless channel show that the voice coder with 2-stage DWT is most appropriate from the viewpoint of compression and waveform recovery. When the line-of-sight component is dominant, the voice coding scheme has good recovery capability even in the moderate signal-to-noise power ratios. Hence, it is considered that the presented scheme will be a technical reference for the future recommendation of voice communication exploiting Zigbee.

• Communications of Mathematical Education
• /
• v.38 no.3
• /
• pp.287-307
• /
• 2024

This study aims to classify and analyze the research topics in mathematics education in both domestic and international contexts based on the Mathematics Subject Classification(MSC)2020, reflecting on the research themes in Korea's mathematics education. For this purpose, data from 6,235 international papers in the zbMATH Open database and 327 papers from domestic journals were collected and analyzed. The analysis showed no statistically significant difference in the distribution of papers between domestic and international contexts, confirmed through the chi-squared independence test. However, a detailed examination revealed that domestic papers tend to focus heavily on specific research topics. This trend suggests a lack of diversity in research topics and insufficient connection with international research trends. To address this issue, the Korean Society of Mathematics Education should provide more systematic MSC2020 classification information and enhance the accessibility of paper searches through zbMATH Open. This will help researchers explore a wider range of topics and strengthen connections with international research trends. Ultimately, it will contribute to the qualitative improvement of mathematics education research in South Korea and increase its global competitiveness.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.610-616
• /
• 2021

This study is a literature review that analyzes the head of Ri election rules and regulations described in the village code, identifies problems, and proposes solutions for these problems. For data collection, a total of 146 village codes was collected from January 2019 to August 2019. The results showed people in most villages vote for the head of Ri according to democratic electoral processes. For system improvement, a one-person, one-vote system was proposed instead of a one-family, one-vote system in order to enhance gender equality and political rights. As for the appointment system, the following changes were proposed: First, candidate eligibility should be improved as only people who were born in that village are eligible; Second, the maximum age of candidacy for the head of Ri should be established as under 65 years old by considering physical ability in the event of disaster occurrences and physical activity required for running village businesses; Third, consecutive terms of the head of Ri when there is no successor should be limited in order to prevent indigenous forces from settling in the local community; and Fourth, education should be provided for building the head of Ri's stature in order to devote to promote public interest for village development.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.6
• /
• pp.629-636
• /
• 2013

There is no safety evaluation index with marine accidents and information of ship's safety management result for good grasp of safety management level of shipping company and effective monitoring. In this paper, we proposed a SMEI(Safety Management Evaluation Index) for evaluation of shipping companies. The SMEI is consist of MAR(marine accidents ratio), SSMR(ship safety management ratio) and SAP(safety advantage point) through brainstorming of the expert group and AHP(analysis hierarchy process)in previous study. And weights of SMEI are calculated using experts's opinions through the Delphi method. We also verified the validity of proposed SMEI to 119 Korean shipping companies with 916 ocean-going ships of Korean flag, which grouped three part (small, mid and big) by number of ship and gross tonnage. And we found out 19 shipping companies, 8 companies in group1 & group2 respectively and 3 companies in group 3, with score below 1.0 by SMEI. In these companies, there are no marine accidents in recent 3 years and appeared low frequency remarkably in the detention and mojor non-conformity by data analysis.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.3B
• /
• pp.289-301
• /
• 2009

In this work, wave run-up heights and resultant wave forces on a vertical revetment due to tsunami (solitary wave) are investigated numerically using a numerical wave tank model called CADMAS-SURF (CDIT, 2001. Research and Development of Numerical Wave Channel (CADMAS-SURF). CDIT library, No. 12, Japan.), which is based on a 2-D Navier-Stokes solver, coupled to a volume of fluid (VOF) method. The third order approximate solution (Fenton, 1972. A ninth-order solution for the solitary wave. J. of Fluid Mech., Vol. 53, No.2, pp.257-271) is used to generate solitary waves and implemented in original CADMAS-SURF code. Numerical results of the wave profiles and forces are in good agreements with available experimental data. Using the numerical results, the regression curves determined from the least-square analysis are proposed, which can be used to determine the maximum wave run-up height and force on a vertical revetment due to tsunami. In addition, the capability of CADMAS-SURF is demonstrated for tsunami wave forces acting on an onshore structure using various configuration computations including the variations of the crown heights of the vertical wall and the position of the onshore structure. Based on the numerical results such as water level, velocity field and wave force, the direct effects of tsunami on an onshore structure are discussed.

• Nuclear Engineering and Technology
• /
• v.16 no.3
• /
• pp.141-154
• /
• 1984

An analysis is presented of key phenomena and scenario which imply some general trends for beyond design-basis-accident in Kori-1 PWR dry containment. The study covers a wide range of severe accident sequences initiated by small break LOCA. The MARCH computer code, with KAERI modifications was used in this analysis. The major emphasis of the paper are two folds, 1) the phenomenologic understanding of severe accident and 2) a study of H2 combustion and debris/ water interactions in a specific small break LOCA for Kori-1 plant. The sensitivity studies for the specific plant data and thermal interaction modelings used in the SASA were performed. The results show that if hydrogen burning does occur at low concentration, the resulting peak pressure does not exceed the design value, while the lower concentration assumption results in repeated burning due to the continuing H$_2$ generation. For debris/water interaction, the particle size has no effect on the magnitude of peak pressure for the amount of water assumed to be in the reactor cavity. But, the occurrence of peak pressure is considerably delayed in case of using the dryout correlation. The peak containment pressure predicted from the hydrogen combustion and steam pressure spite during full core meltdown scenario does not present a severe threat to the containment integrity.

• Journal of dental hygiene science
• /
• v.16 no.5
• /
• pp.339-348
• /
• 2016

We investigated the gender-specific association between average volume of alcohol consumption, binge drinking, and periodontitis using representative nationwide data. In total, we included 3,549 men and 4,810 women, aged 19 years and older, who participated in the sixth Korea National Health and Nutrition Examination Survey performed in 2013~2014. According to the average volume of alcohol consumption, study participants were grouped as follows: mild drinkers (0.1~2.0 drinks/day in men and 0.1~1.0 drink/day in women), moderate drinkers (2.1~4.0 drinks/day in men and 1.1~2.0 drinks/day in women), and heavy drinkers (>4.0 drinks/day in men and >2.0 drinks/day in women). Additionally, binge drinking was categorized as never (no binge drinking), rarely (<1 time/month), occasionally (1 time/month), frequently (1 time/week), and always (almost every day/week). Periodontitis was defined as a community periodontal index equal to code 3 or greater. In men, after controlling for covariates, the association between average volume of alcohol consumption and periodontitis showed a J-shaped curve; the risk of periodontitis was significantly higher in moderate drinkers (odds ratio [OR], 1.25; 95% confidence interval [CI], 1.01~1.56) and heavy drinkers (OR, 1.39; 95% CI, 1.04~1.87) than in mild drinkers. In contrast, no significant association between average volume of alcohol consumption and periodontitis was observed in women. In a fully adjusted analysis, which used 'never binge drinking' as a reference, a significant dose-response relationship between binge drinking and periodontitis was observed only in men: rarely (OR, 1.64; 95% CI, 1.16~2.34), occasionally (OR, 1.51; 95% CI, 1.05~2.16), frequently (OR, 1.58; 95% CI, 1.07~2.33), and always (OR, 2.56; 95% CI, 1.56~4.22) (p for trend=0.005). In conclusion, unhealthy drinking patterns such as moderate or heavy alcohol consumption and binge drinking were significantly associated with periodontitis in men but not in women.

• Journal of Radiation Industry
• /
• v.17 no.3
• /
• pp.283-292
• /
• 2023

Spent nuclear fuel corresponds to high-level radioactive waste that has high decay heat and radioactivity. Accordingly, Spent nuclear fuel withdrawn from the reactor core is primarily stored and managed in a spent nuclear fuel pool in the nuclear power plant to reduce decay heat and radioactivity. In Korea, most nuclear power plant store all spent nuclear fuel in a spent nuclear fuel pool. For wet storage, there are no defense in depth different with reactor core. The study related to spent nuclear fuel pool accident should be carried out to ensure safety. Therefore, it is necessary to analyze previous study cases related to safety of spent nuclear fuel pool and accident cases to build foundational knowledge. The Objective of this study is to analyze study cases of safety assessment and cases for spent nuclear fuel pool accident. For analyzing study cases of safety assessment, possible phenomena when spent nuclear fuel pool accident occurring identified, Subsequently, study cases for safety assessment about each phenomena were investigated, and materials & methods and results for each study are analyzed. For analyzing cases for spent nuclear fuel pool accident, we analyzed accident cases caused by loss of cooling and loss of coolant in spent nuclear fuel pool. Subsequently, causes and change of water level and temperature by each accident case are analyzed. As a result of the analysis on study cases of spent nuclear fuel pool accident, the results of the study conducted by each research institute were vary depending on the computer code, materials & methods of experiment and major assumptions used in the study. As a result of analyzing cases for spent nuclear fuel pool accident, it was found that accident cases for loss of cooling is more than cases for loss of coolant accident. Even though the types of accident in spent nuclear fuel pool were similar, the specific causes were different by each accident case. All the accident cases analyzed did not lead to severe accidents, such as nuclear fuel being exposed to the air. The result of this study will be used as fundamental data for study on spent nuclear fuel pool accident that will be conducted in the future.

• Journal of Intelligence and Information Systems
• /
• v.27 no.2
• /
• pp.33-54
• /
• 2021

With the fourth industrial revolution and the arrival of the New Normal era due to Corona, the importance of Non-contact technologies such as artificial intelligence and big data research has been increasing. Convergent research is being conducted in earnest to keep up with these research trends, but not many studies have been conducted in the area of nuclear research using artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. This study was conducted to confirm the applicability of data science analysis techniques to the field of nuclear research. Furthermore, the study of identifying trends in nuclear spent fuel recognition is critical in terms of being able to determine directions to nuclear industry policies and respond in advance to changes in industrial policies. For those reasons, this study conducted a media trend analysis of pyroprocessing, a spent nuclear fuel treatment technology. We objectively analyze changes in media perception of spent nuclear fuel dry treatment techniques by applying text mining analysis techniques. Text data specializing in Naver's web news articles, including the keywords "Pyroprocessing" and "Sodium Cooled Reactor," were collected through Python code to identify changes in perception over time. The analysis period was set from 2007 to 2020, when the first article was published, and detailed and multi-layered analysis of text data was carried out through analysis methods such as word cloud writing based on frequency analysis, TF-IDF and degree centrality calculation. Analysis of the frequency of the keyword showed that there was a change in media perception of spent nuclear fuel dry treatment technology in the mid-2010s, which was influenced by the Gyeongju earthquake in 2016 and the implementation of the new government's energy conversion policy in 2017. Therefore, trend analysis was conducted based on the corresponding time period, and word frequency analysis, TF-IDF, degree centrality values, and semantic network graphs were derived. Studies show that before the 2010s, media perception of spent nuclear fuel dry treatment technology was diplomatic and positive. However, over time, the frequency of keywords such as "safety", "reexamination", "disposal", and "disassembly" has increased, indicating that the sustainability of spent nuclear fuel dry treatment technology is being seriously considered. It was confirmed that social awareness also changed as spent nuclear fuel dry treatment technology, which was recognized as a political and diplomatic technology, became ambiguous due to changes in domestic policy. This means that domestic policy changes such as nuclear power policy have a greater impact on media perceptions than issues of "spent nuclear fuel processing technology" itself. This seems to be because nuclear policy is a socially more discussed and public-friendly topic than spent nuclear fuel. Therefore, in order to improve social awareness of spent nuclear fuel processing technology, it would be necessary to provide sufficient information about this, and linking it to nuclear policy issues would also be a good idea. In addition, the study highlighted the importance of social science research in nuclear power. It is necessary to apply the social sciences sector widely to the nuclear engineering sector, and considering national policy changes, we could confirm that the nuclear industry would be sustainable. However, this study has limitations that it has applied big data analysis methods only to detailed research areas such as "Pyroprocessing," a spent nuclear fuel dry processing technology. Furthermore, there was no clear basis for the cause of the change in social perception, and only news articles were analyzed to determine social perception. Considering future comments, it is expected that more reliable results will be produced and efficiently used in the field of nuclear policy research if a media trend analysis study on nuclear power is conducted. Recently, the development of uncontact-related technologies such as artificial intelligence and big data research is accelerating in the wake of the recent arrival of the New Normal era caused by corona. Convergence research is being conducted in earnest in various research fields to follow these research trends, but not many studies have been conducted in the nuclear field with artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. The academic significance of this study is that it was possible to confirm the applicability of data science analysis technology in the field of nuclear research. Furthermore, due to the impact of current government energy policies such as nuclear power plant reductions, re-evaluation of spent fuel treatment technology research is undertaken, and key keyword analysis in the field can contribute to future research orientation. It is important to consider the views of others outside, not just the safety technology and engineering integrity of nuclear power, and further reconsider whether it is appropriate to discuss nuclear engineering technology internally. In addition, if multidisciplinary research on nuclear power is carried out, reasonable alternatives can be prepared to maintain the nuclear industry.