• Information Systems Review
• /
• v.22 no.2
• /
• pp.137-166
• /
• 2020

While South Koreans overseas travelling rate has been increased every year, domestic travelling rate has been at a standstill for several years. The purpose of this study is to analyze domestic traveling styles of Koreans according to their generations in order to provide generation-specific traveling services. For this purpose, we categorized the survey respondents into four different generations, which are Millennium (age 19~34), X generation (35~54), Baby Boomer (55~64) and senior by following the criterions of the Korea National Tourism Organization. After then, we analyze factors related to travel preparation process, the actual traveling activities and satisfaction after the travel. In this study, 16,713 data collected by the Ministry of Culture, Sports and Tourism are used. The results of this study show that Korean people tends to acquire domestic traveling information from their own or acquaintances past experiences. Also, they do not prefer the organized trip for domestic travels, thus do not buy package products a lot. In addition, natural scenery, rich in cultural heritage, and convenient accommodation are the most important determinant factors affecting the overall travel satisfaction of level for all generations. The traveling characteristics for each generation are as follows. Millennium get traveling information from the internet a lot, and more specifically, they refer portal sites and social network services (SNS) in many cases. Also, they tend to travel in summer peak season to popular destinations and pursues active traveling experiences. Generation X has similar traveling patterns with Millennium, however they major transportation method is using their own car. Also, transportation convenience and satisfactory leisure activity are important factors affecting the overall satisfaction level to Generation X. On the other hand, Baby boomer generation has a greater emphasis on appreciation of nature, visiting famous restaurants, and relaxation, rather than actively participating experiencing programs. They travel evenly in summer and spring/fall season to many different areas instead of focusing on popular tourist spots. In addition, shopping and eating delicious food are the important factors affecting the overall satisfaction level for them. Lastly, Senior generation has similar characteristics with Baby boomer in many ways, however, they travel a lot on the same day using public transportations or car rental service. They prefer spring and autumn trips rather than summer peak season, and tend to buy packaged travel products a lot compared with other generations. If these different traveling characteristics of each generation are considered for organizing and customizing tourism services, it is expected that domestic tourism satisfaction level will be ultimately increased.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.15 no.2
• /
• pp.13-20
• /
• 2011

Purpose: The limited FOV(Field of View) of CT (Computed Tomography) can cause truncation artifact at external DFOV (Display Field of View) in PET/CT image. In our study, we measured the difference of SUV and compared the influence affecting to the image reconstructed with the extended DFOV. Materials and Methods: NEMA 1994 PET Phantom was filled with $^{18}F$(FDG) of 5.3 kBq/mL and placed at the center of FOV. Phantom images were acquired through emission scan. Shift the phantom's location to the external edge of DFOV and images were acquired with same method. All of acquired data through each experiment were reconstructed with same method, DFOV was applied 50 cm and 70 cm respectively. Then ROI was set up on the emission image, performed the comparative analysis SUV. In the clinical test, patient group shown truncation artifact was selected. ROI was set up at the liver of patient's image and performed the comparative analysis SUV according to the change of DFOV. Results: The pixel size was increase from 3.91 mm to 5.47 mm according to the DFOV increment in the centered location phantom study. When extended DFOV was applied, $_{max}SUV$ of ROI was decreased from 1.49 to 1.35. In case of shifted the center of phantom location study, $_{max}SUV$ was decreased from 1.30 to 1.20. The $_{max}SUV$ was 1.51 at the truncated region in the extended DFOV. The difference of the $_{max}SUV$ was 25.9% higher at the outside of the truncated region than inside. When the extended DFOV was applied, $_{max}SUV$ was decreased from 3.38 to 3.13. Conclusion: When the extended DFOV was applied, $_{max}SUV$ decreasing phenomenon can cause pixel to pixel noise by increasing of pixel size. In this reason, $_{max}SUV$ was underestimated. Therefore, We should consider the underestimation of quantitative result in the whole image plane in case of patient study applied extended DFOV protocol. Consequently, the result of the quantitative analysis may show more higher than inside at the truncated region.

• Journal of Korean Society of Environmental Engineers
• /
• v.34 no.8
• /
• pp.574-582
• /
• 2012

This study presents the concentrations of the polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by United States Environmental Protection Agency (US EPA), in 98 sludges from 54 industrial wastewater treatment facilities of South Korea. The mean concentrations of ${\Sigma}_{16}PAHs$ were ranged from 32.5 ${\mu}g/kg-dw$ to 1189.3 ${\mu}g/kg-dw$ by industries, and the highest content was found in the petrochemical industry, followed by chemical, clothing manufacturing and dying, pulp and papermaking, secondary wastewater treatment, and food/beverage producing industries. Comparisons to the EU and Danish standards of ${\Sigma}_{16}PAHs$ in sewage sludge for land application showed only two samples (one from petrochemical, and the other from chemical industry) exceeded the limits. ANOVA test with PAH concentrations as variables revealed no statistically significant influences by industrial types and sampling time (i.e., seasonal variations). Pearson correlations between individual PAHs showed strong relationships (r>0.7) among 4-ring PAHs. Concentrations of acenaphthylene, anthracene, fluoranthene, benzo(a)anthracene, benzo(f)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene presented strong correlations to ${\Sigma}_{16}PAHs$. Principal component analysis discriminated entire samples into three groups by two principal components (PC1 and PC2) with 70% of data variations, in which industrial types were not of importance, but a dominance of certain PAHs. Samples in group-I, which is high PC1 and low PC2, were characterized by a dominance of 2-ring PAHs, and in group-II, PC1 and PC2 showed a linear relation, was dominant 4-ring PAHs. Group-III with low PC1 and high PC2 includes 17 samples showing a noticeably high contribution of 3-ring PAHs to ${\Sigma}_{16}PAHs$. This study provides concentrations of PAHs in industrial sludges collected from a wide variety of sources (six industrial types) and two seasons of sampling events, and the comparison of ${\Sigma}_{16}PAHs$ with other studies are also discussed.

• Food Science and Preservation
• /
• v.20 no.6
• /
• pp.791-797
• /
• 2013

This study was conducted to investigate the changes in the composition and microbiological properties of domestic sun-dried salt (white and gray salts) according to their collection time and production method. The results showed that the moisture contents of the white and gray sun-dried salts were 10.4~13.2% and 5.2~8.0%, respectively, and the sand contents were 0.1% and 0.2~0.3%, respectively, according to the month. Several samples exceeded the criteria of 15% moisture content and 0.2% sand content. The ash content and salinity of gray salt (below 85% and 90%, respectively) were higher than those of white salt (both below 80%). The total chloride contents of the salts collected in September and October were slightly lower than that of the others and exceeded the criteria of above 40%. In the case of mineral contents, there was no significant difference among the collection times because the analyses showed a marked deviation. The microbiological analysis showed that there was no significant difference among the production method, but the salt samples collected in September and October had relatively high detection rates of total aerobe, staphylococci, and halophilic bacteria.

• Korean Journal of Clinical Laboratory Science
• /
• v.49 no.3
• /
• pp.239-247
• /
• 2017

Among the commonly known tools to diagnose diabetes are fasting plasma glucose (FPG), HbA1c., and OGTT known as gold standard. However, there can be many disagreements on the ways to diagnose diabetes. In this study, we examined the differences of the types of diabetes according to the applicability of FPG and HbA1c. Moreover, we evaluated the concordance of diagnosis. We excluded subjects with missing glucose and HbA1c data, as well as those previously diagnosed with diabetes, and those who fasted less than 8 hours. The data of 4,502 subjects (1,956 men and 2,546 women) from the 2015 KNHNES were analyzed. We divided these patients into three categories which are normal, prediabetes, and diabetes, based on the FPG and HbA1c. In men, the number of subjects with FPG ranging from 100 to 125 mg/dL and HbA1c ${\geq}6.5%$ was 23 out of 664, and the number of subjects with FPG < 126 mg/dL and HbA1c ${\geq}6.5%$ was 39 out of 86 newly diagnosed diabetes patients. The concordance rate was as follows: Normal 80.3%, prediabetes 44.9%, and diabetes 54.7%. The coefficient of Cohen's Kappa was 0.322 in men and 0.362 in women; this suggests that both gender showed a low concordance rate. However, when we divided them into two categories (nondiabetes and diabetes), Kappa was 0.582 in men and 0.637 in women, showing a relatively high concordance rate. While all subjects with FPG ${\geq}126mg/dL$ showed a significantly high HOMA IR, all subjects with FPG < 126 mg/dL showed a significantly high QUICKI. Considering the low concordance rate for the diagnosis of diabetes and characteristic of diagnostic tests, it is necessary to combine the related tests for diagnosing diabetes.

• Korean Security Journal
• /
• no.50
• /
• pp.209-237
• /
• 2017

Theories on 'opportunity for crime' have utilized CCTV in crime prevention approach, and empirical studies showing crime prevention effects of CCTV have supported expansion of CCTV installation. Particularly, in Korea, the number of CCTV installation had tripled from 2011 to 2015, and governmental policies regarding CCTV have become one of the mainstream social control strategies. Although a couple of empirical studies showed decrease in crime rate due to CCTV installation, there is no study investigating B/C analysis(Benefit vs. cost analysis) of CCTV installation. B/C analysis results will be beneficial for official decision-making of criminal justice policy, and this study is purported to produce such fundamental evidence for policy making procedure. To fulfill this goal, this study collected data on financial information, crime data between 2011 and 2015 across the nation from 232 governmental district offices and the Korean National Police. This study then conducted two different B/C analyses(simple B/C analysis, regression-based B/C analysis). The simple B/C analysis results showed that 1) total costs for CCTV installation in 2014 was 68,626,000,000 won(approximately, US$57,188,333.00, money exchange rate 1200won=US$1), 2) benefits of crime reduction was 90,888,000,000 won(appx. US$75,740,000), and 3) B/C rate was 1.32. The regression-based B/C analysis results showed that 1) B/C rate was 1.52 when only reduced costs of criminal justice processes for crime employed, and 2) B/C rate was 3.62 when overall social costs including reduced costs of criminal justice processes and social benefits, e.g., reduction in costs for managing fear of crime, due to the crime reduction. Based on the results, this study provided policy implications.

• Korea journal of population studies
• /
• v.10 no.2
• /
• pp.58-81
• /
• 1987

The purpose of this study is to examine major factors that affect patterns of living arrangements of older Korean noncitizens in the United States using the 1990 8% Public Use Microdata Sample(PUMS). In order to do so, I analyzed the effects of four factors including acculturation(English proficiency and Age at migration), economic circumstances(Personal Income and Supplemental Security Income: SSI receipt), health status(Mobility and Personal care limitation), and the ethnic community. The results show that acculturation and economic circumstances play an important role in determining the patterns of living arrangements among older Korean aliens, whereas the health status and the ethnic community do not show consistent effects. Regardless of marital status, the impact of age at migration is positively associated with solitary living of older Korean noncitizens, though, the effect of English proficiency show the opposite direction in accordance with marital status. That is, among nonmarried elders, those who cannot speak English are more likely to live alone. The case is reverse for married elders. The impact of economic feasibility is also positively associated with independent living arrangements. Those who receive SSI are much more likely to live apart from family, and elders whose annual personal income between $5,001 and $10,000 have the greatest propensity of solitary living-a large proportion of their income source is SSI. Individuals who receive SSI are also qualified to collect Medicaid, food stamps, rent subsidies, and other welfare benefits. In a sense, the economic feasibility provided by welfare benefits is the key determinant of independent living of older Korean noncitizens. Therefore, the recent welfare reform which denies legal aliens welfare benefits such as SSI and food stamps will severly affect the present living arrangements of older Korean aliens, and give economic burden to their family member The findings also show that there are significant differences within the elderly Korean Americans in terms of demographics, income, fertility, health status, and patterns of living arrangements by U.S. citizenship status. In particular, after controlling for age at migration as a proxy for acculturation, there is a statistically significant variation in living arrangements between elderly Korean noncitizens and naturalized citizens. For both theoretical and methodological reasons, future research on minority aging needs to investigate the concept of U.S. citizenship status for its impact on patterns of living arrangements among the minority elderly.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.1
• /
• pp.85-91
• /
• 2010

Sodium is a major component that maintains homeostasis and physiological state in body. It is an essential mineral that the body cannot produce for itself, so it must be supplied from food. On the other hand, overindulgence is one cause of hypertension, stroke, stomach cancer, osteoporosis and kidney disease. The purpose of this study was to monitor sodium content in meals of school foodservice. In this study, 801 samples (main/side dishes) were collected from 8 school foodservice in Busan and Gyeongsangbuk-do, Korea. Samples were classified into 21 food items, which were cooked rices, cooked rice with seasoning, noodles, cooked gruels, soups, stews, tang and chon-gol, stir-fried foods, fried foods, pan-fried foods, hard-boiled foods, roasted foods, steamed foods, seasoned vegetables, preserved foods, kimchis, sauces, fruits, breads and snacks, beverages, and dairy products. The samples were analyzed by AAS (atomic absorption spectrometry) after microwave digestion. The sodium content of sauces (1459 mg/100 g) and preserved foods (1165 mg/100 g) was higher than those of other dishes. Aside from them, sodium contents of roasted foods (894 mg/100 g), hard-boiled foods (786 mg/100 g) and kimchis (737 mg/100 g) were relatively higher than the others. Sodium intakes from meals of school foodservice were calculated by multiplying food intakes by sodium contents. The average sodium intakes from one serving of school foodservice were 605 mg for younger boys, 572 mg for younger girls, 774 mg for older boys, 730 mg for older girls in elementary school. Boys in middle school took in 1423 mg Na whereas girls consumed 1063 mg Na in middle school. Results from this study can be useful for establishing database of sodium contents and intake in meals of school foodservice. The database will be helpful for providing information on managing food for children.

• Journal of Intelligence and Information Systems
• /
• v.20 no.4
• /
• pp.25-41
• /
• 2014

Recently, the number of social media users has increased rapidly because of the prevalence of smart devices. As a result, the amount of real-time data has been increasing exponentially, which, in turn, is generating more interest in using such data to create added value. For instance, several attempts are being made to analyze the relevant search keywords that are frequently used on new portal sites and the words that are regularly mentioned on various social media in order to identify social issues. The technique of "topic analysis" is employed in order to identify topics and themes from a large amount of text documents. As one of the most prevalent applications of topic analysis, the technique of issue tracking investigates changes in the social issues that are identified through topic analysis. Currently, traditional issue tracking is conducted by identifying the main topics of documents that cover an entire period at the same time and analyzing the occurrence of each topic by the period of occurrence. However, this traditional issue tracking approach has two limitations. First, when a new period is included, topic analysis must be repeated for all the documents of the entire period, rather than being conducted only on the new documents of the added period. This creates practical limitations in the form of significant time and cost burdens. Therefore, this traditional approach is difficult to apply in most applications that need to perform an analysis on the additional period. Second, the issue is not only generated and terminated constantly, but also one issue can sometimes be distributed into several issues or multiple issues can be integrated into one single issue. In other words, each issue is characterized by a life cycle that consists of the stages of creation, transition (merging and segmentation), and termination. The existing issue tracking methods do not address the connection and effect relationship between these issues. The purpose of this study is to overcome the two limitations of the existing issue tracking method, one being the limitation regarding the analysis method and the other being the limitation involving the lack of consideration of the changeability of the issues. Let us assume that we perform multiple topic analysis for each multiple period. Then it is essential to map issues of different periods in order to trace trend of issues. However, it is not easy to discover connection between issues of different periods because the issues derived for each period mutually contain heterogeneity. In this study, to overcome these limitations without having to analyze the entire period's documents simultaneously, the analysis can be performed independently for each period. In addition, we performed issue mapping to link the identified issues of each period. An integrated approach on each details period was presented, and the issue flow of the entire integrated period was depicted in this study. Thus, as the entire process of the issue life cycle, including the stages of creation, transition (merging and segmentation), and extinction, is identified and examined systematically, the changeability of the issues was analyzed in this study. The proposed methodology is highly efficient in terms of time and cost, as it sufficiently considered the changeability of the issues. Further, the results of this study can be used to adapt the methodology to a practical situation. By applying the proposed methodology to actual Internet news, the potential practical applications of the proposed methodology are analyzed. Consequently, the proposed methodology was able to extend the period of the analysis and it could follow the course of progress of each issue's life cycle. Further, this methodology can facilitate a clearer understanding of complex social phenomena using topic analysis.

• Korean Journal of Remote Sensing
• /
• v.28 no.1
• /
• pp.69-77
• /
• 2012

Surface insolation is one of the major indicators for climate research over the Earth system. For the climate research, long-term data and wide range of spatial coverage from the data observed by two or more of satellites of the same orbit are needed. It is important to improve the continuity and consistency of the derived products, such as surface insolation, from different satellites. In this study, surface insolations based on Geostationary Operational Environmental Satellite (GOES-9) and Multi-functional Transport Satellites (MTSAT-1R) were compared during overlap period using physical model of insolation to find ways to improve the consistency and continuity between two satellites through comparison of each channel data and ground observation data. The thermal infrared brightness temperature of two satellites show a relatively good agreement between two satellites : rootmean square error (RMSE)=5.595 Kelvin; Bias=2.065 Kelvin. Whereas, visible channels shown a quite different values, but it distributed similar tendency. And the surface insolations from two satellites are different from the ground observation data. To improve the quality of retrieved insolations, we have reproduced surface insolation of each satellite through adjustment of the Cloud Factor, and the Cloud Factor for GOES-9 satellite is modified based on the analysis result of difference channel data. As a result, the insolations estimated from GOES-9 for cloudy conditions show good agreement with MTSAT-1R and ground observation : RMSE=$83.439W\;m^{-2}$ Bias=$27.296W\;m^{-2}$. The result improved accuracy confirms that the modification of Cloud Factor for GOES-9 can improve the continuity and consistency of the insolations derived from two or more satellites.