• Journal of the Korea Society of Computer and Information
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• v.25 no.5
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• pp.47-56
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• 2020

The stock index is used not only as an economic indicator for a country, but also as an indicator for investment judgment, which is why research into predicting the stock index is ongoing. The task of predicting the stock price index involves technical, basic, and psychological factors, and it is also necessary to consider complex factors for prediction accuracy. Therefore, it is necessary to study the model for predicting the stock price index by selecting and reflecting technical and auxiliary factors that affect the fluctuation of the stock price according to the stock price. Most of the existing studies related to this are forecasting studies that use news information or macroeconomic indicators that create market fluctuations, or reflect only a few combinations of indicators. In this paper, this we propose to present an effective combination of the news information sentiment analysis and various macroeconomic indicators in order to predict the US Dow Jones Index. After Crawling more than 93,000 business news from the New York Times for two years, the sentiment results analyzed using the latest natural language processing techniques BERT and NLTK, along with five macroeconomic indicators, gold prices, oil prices, and five foreign exchange rates affecting the US economy Combination was applied to the prediction algorithm LSTM, which is known to be the most suitable for combining numeric and text information. As a result of experimenting with various combinations, the combination of DJI, NLTK, BERT, OIL, GOLD, and EURUSD in the DJI index prediction yielded the smallest MSE value.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.644-657
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• 2020

As the development of urbanization has cause some environmental problems and natural disasters such as natural earthquakes and floods have brought about impact, designers have turned their attention to the independent prevention ability of urban ecosystems in face of environmental pollution and natural disasters, as well as its ability to adapt to the future. This study introduces 'elasticity theory' to discuss the practical application of elasticity design in landscapes and to solve the problem of lack of elasticity in space, which can provide more scientific reference meaning to create economic, cultural, and social values for space. After selecting 'The High Line' as the object, this paper investigates the previous theories and practical cases, and infers ecology, sustainability, diversity, and adaptability. And then this paper applies five components and analyzes the specific application of these five components of the landscape spatial elasticity strategy, and summarizes the application characteristics and influencing factors of elasticity design in 'The High Line' landscape planning. It can be known from the research that elasticity strategy which is reflected in the design process is the systematic management of landscape space. Elasticity design itself can strengthen environment quality and satisfy the requirements of the environment to defense external shocks so as to adapt to environment changes. Therefore, the elasticity design can strengthen the sustainable development of the city and establish a periodic recycle system.

• Advanced Industrial SCIence
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• v.2 no.3
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• pp.22-28
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• 2023

In this study, we conducted research on the automated trading of U.S. stocks through a volatility strategy using the Fear and Greed index. Volatility in the stock market is a common phenomenon that can lead to fluctuations in stock prices. Investors can capitalize on this volatility by implementing a strategy based on it, involving the buying and selling of stocks based on their expected level of volatility. The goal of this thesis is to investigate the effectiveness of the volatility strategy in generating profits in the stock market.This study employs a quantitative research methodology using secondary data from the stock market. The dataset comprises daily stock prices and daily volatility measures for the S&P 500 index stocks. Over a five-year period spanning from 2016 to 2020, the stocks were listed on the New York Stock Exchange (NYSE). The strategy involves purchasing stocks from the low volatility group and selling stocks from the high volatility group. The results indicate that the volatility strategy yields positive returns, with an average annual return of 9.2%, compared to the benchmark return of 7.5% for the sample period. Furthermore, the findings demonstrate that the strategy outperforms the benchmark return in four out of the five years within the sample period. Particularly noteworthy is the strategy's performance during periods of high market volatility, such as the COVID-19 pandemic in 2020, where it generated a return of 14.6%, as opposed to the benchmark return of 5.5%.

• Journal of Navigation and Port Research
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• v.30 no.10 s.116
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• pp.809-817
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• 2006

Shipping and ports have important roles as the nodes and links in maritime logistics. The environment between shipping and ports is interrelated and has been changing' together. Recently, the changes of shipping and ports are rapidly in progress and it is expected to be developed complementarily. Especially, mega carriers reduce the number of ports of calls because the size of ships is becoming bigger and bigger and the 'hub and spokes' strategy is appeared. Therefore, the position of a hub port by the region has questioned This paper aims to research the competitive ports by the region on the basis of the patterns when mega carriers call at ports. Six regions, Far East, Southeast Asia, Northwest America, Northeast America, West Europe and Mediterranean, are organized for this research. According to the volume of cargoes, the top five ports of each region are analyzed. As a result, the competitive ports by the region are Shanghai, Hong Kong, Los Angeles, New York New Jersey, Rotterdam and Gioia Tauro.

• Journal of the Korean Society of Food Culture
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• v.27 no.6
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• pp.666-676
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• 2012

The purpose of this study was to propose effective marketing communication strategies for overseas Korean restaurants through a multilateral comparison analysis of American, Chinese, and Japanese consumers' attitudes towards communication media and Korean restaurants. The survey was written in English, Chinese, and Japanese, with guideline for surveyors, and conducted using both online and offline methods. Samples were collected from five major cities - Los Angeles, New York, Tokyo, Beijing and Shanghai, which are the foothold for the globalization of Korean food. When it comes to attitudes towards communication media, word-of-mouth showed a high mean value, indicating it as the most useful and reliable media recognized by consumers who visited Korean restaurants. Furthermore, the necessity of recognizing the importance of visual communication in the physical environment of Korean restaurants and specialized websites, featuring restaurants and gourmet food, was observed. Consumers in all three nations chose word-of-mouth as the most useful and reliable media for learning about Korean restaurants. In addition, American consumers highly depended on signage and restaurant exteriors. Chinese consumers highly recognized the usefulness and reliability of offline media, such as newspapers, magazines, and events, while Japanese consumers considered online media, such as gourmet websites, blogs and social networks, as useful and reliable sources. A significantly positive attitude and high value was observed in all who had visited Korean restaurants. American and Japanese consumers had a significantly higher rate of intention to visit Korean restaurants in the future and to tell others about their satisfaction with Korean restaurants. Meanwhile, the average rate of prior preference for Korean restaurants (when choosing restaurants) was the lowest in all three countries. This study is useful for both the Korean government and food enterprises abroad to plan and develop marketing communication strategies properly for overseas Korean restaurants.

• Journal of the Korean earth science society
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• v.33 no.7
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• pp.645-657
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• 2012

The purpose of this study was to investigate pre-service elementary teachers' conceptions about the relative sizes of celestial bodies including the universe, galaxy, star, planet, satellite, asteroid, and comet, which were presented in elementary school science textbook. This study also examined the causes of their misconceptions as shown in the study. Sixty three pre-service elementary teachers participated in this study. The survey was developed for this study that asked to make an order of relative sizes of the given celestial bodies and to write scientific facts about each of the celestial bodies. The survey items were analyzed by simple descriptive statistics, and the written responses were analyzed using qualitative and inductive methods. The results showed that only five (7.9%) of the participants correctly answered about the relative size of the given celestial bodies. There were three common misconceptions identified in relation to the relative sizes of the celestial bodies; more than 20% of the participants had: (1) a planet is bigger than a star (46.0% of the participants), (2) an asteroid is bigger than satellite (58.7%), 3) a comet is bigger than a star (22.2%).

• Journal of Chest Surgery
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• v.29 no.1
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• pp.32-37
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• 1996

Between May 1991 and September 1995, 7 patients underwent surgical repair of ventricular septal defect (VSD) complicated with myocardial infarction in Asan Medical Center. The patients included two male and five female. The ages of patients were ranged from 54 years to 76 years with a mean of 65 years. The sites of postinfarction ventricular septal defect were consist of anterior septal defect in 6 patients and anteroposterior septal defect in 1 patient. Preoperative 2D-echocardiography & angiography were performed in all patients in order to measure ventricular function and evaluate the extent of coronary artery disease. The operations were delayed till mean 24 $\pm$ 12days after myocardial infarction. All patients underwent infarctectomy and Teflon patch closures through the area of the left ventricle infarction or aneurysm in the anterior or apical aspect of postinfarction ventricular septal defect. The ventricular septal defect repaired simultaneously with coronary artery b pass graft in 3 patients, with ventricular aneurysmectomy in 5 patients, and with left ventricular thrombectomy in 1 patient. Patch fixation in the left side of interventricular septum by tracts-septal interrupted pledget suture reduced the recurrence rate of VSD. There were 2 postoperative complications : One with pneumonia, 1 patient with the skin necrosis of left thigh. There was ilo early death. The 6 patients except for one emigrant were followed up postoperatively between 3 and 63 months(mean .28 months), without any sequelae and late death. They are in New York Heart Association functional class I-II.

• Journal of Chest Surgery
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• v.49 no.3
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• pp.165-170
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• 2016

Background: In elderly high-risk surgical patients, sutureless aortic valve replacement (AVR) should be an alternative to standard AVR. The potential advantages of sutureless aortic prostheses include reducing cross-clamping and cardiopulmonary bypass (CPB) time and facilitating minimally invasive surgery and complex cardiac interventions, while maintaining satisfactory hemodynamic outcomes and low rates of paravalvular leakage. The current study reports our single-center experience regarding the early outcomes of sutureless aortic valve implantation. Methods: Between October 2012 and June 2015, 65 patients scheduled for surgical valve replacement with symptomatic aortic valve disease and New York Heart Association function of class II or higher were included to this study. Perceval S (Sorin Biomedica Cardio Srl, Sallugia, Italy) and Edwards Intuity (Edwards Lifesciences, Irvine, CA, USA) valves were used. Results: The mean age of the patients was $71.15{\pm}8.60years$. Forty-four patients (67.7%) were female. The average preoperative left ventricular ejection fraction was $56.9{\pm}9.93$. The CPB time was $96.51{\pm}41.27minutes$ and the cross-clamping time was $60.85{\pm}27.08minutes$. The intubation time was $8.95{\pm}4.19hours$, and the intensive care unit and hospital stays were $2.89{\pm}1.42days$ and $7.86{\pm}1.42days$, respectively. The mean quantity of drainage from chest tubes was $407.69{\pm}149.28mL$. The hospital mortality rate was 3.1%. A total of five patients (7.69%) died during follow-up. The mean follow-up time was $687.24{\pm}24.76days$. The one-year survival rate was over 90%. Conclusion: In the last few years, several models of valvular sutureless bioprostheses have been developed. The present study evaluating the single-center early outcomes of sutureless aortic valve implantation presents the results of an innovative surgical technique, finding that it resulted in appropriate hemodynamic conditions with acceptable ischemic time.

• Journal of Chest Surgery
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• v.37 no.7
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• pp.578-584
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• 2004

Sinus of Valsalva aneurysm is a rare cardiac anomaly and a long-term survival after surgical treatment has not been well established. This study was designed to evaluate the long-term surgical results after the repair of sinus Valsalva aneurysm. Material and Method: From April 1991 to November 2003, 35 patients (23 male, 12 female, mean age 35.2 years, range 11∼64) underwent operation for sinus of Valsalva aneurysm. Twenty six patients (74.3%) were in the New York Heart Association (NYHA) class III∼IV before surgery. In preoperative echocardiogram, mean EF was 63.32 $\pm$ 11.43% and nine patients (25.7%) were in AR grade III∼IV. Direct closure, patch closure of ruptured sinus Valsalva were performed in fourteen patients (46.7%), sixteen patients (53.3%) respectively. Aortic valve replacement, valvuloplasty were performed in five patients (14.3%), three patients (8.6%) respectively. Three patients (8.6%) underwent the Bentall procedure. Concomitant procedures were performed in 15 patients (42.9%), which were closure of VSD and ASD. Mean CPB time and ACC time were 116.79 $\pm$ 38.79 and 81.2 $\pm$ 28.97 minutes. Result: There was no operative mortality. One patient (2.9%) developed complete heart block that required a permanent pacemaker implantation. Three patients (8.6%) required reoperation due to a recurred rupture of the sinus Valsalva aneurysm and developed aortic insufficiency. Mean follow-up time was 58.55 $\pm$ 38.38 months. There was one late death. Actuarial 5 year freedom rate from reoperation was 87.1 $\pm$ 7%. Conclusion: Surgical treatment for sinus of Valsalva aneurysm is safe and has satisfactory long-term results.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.666-680
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• 2006

To obtain basic data for the utilization of saltwort (Salicornia herbacea L.) as a functional ingredient in steamed foam cake, the optimum component ratios for major raw ingredients (saltwort, salt, and wheat flour) as independent variables that affect the product quality were scientifically determined using RSM (response surface methodology) technique. A three-factor and five-level rotational central composite design was used for treatment arrangement. The complete design consisted of 16 experimental points. The three independent variables selected for the RSM experiment were amounts of saltwort (X$_1$, 5${\sim}$25 g), salt (X$_2$, 0${\sim}$10 g), and wheat flour (X$_3$, 470${\sim}$530 g). The optimum responses in specific gravity of the batter and volume, color, texture, and sensory evaluation result of the cake were obtained. The specific gravity and viscosity of the batter at p<0.01 was verified from the regression curve. The characteristic of the batter was influenced by all independent variables, but was extremely dependent on the amount of saltwort ordinary points of the surface responses from the batter formed the minimum points for specific gravities of the batter while viscosities of the batter appeared with the saddle points. Analysis of the response indicated that the amount of saltwort was the most influential factor over the physical properties of the cake, among the dependent variables. Ordinary points of the surface responses from the cake formed the maximum points for loaf volume, hardness gumminess, and chewiness, while Hunter colorimetric parameters appeared with the saddle points. The result indicated that level of the saltwort deviating more or less from the optimal amount decreased the volume and increased the specific gravity with less tender product. Ordinary points of the surface responses of the sensory evaluation scores from the cake formed the maximum points for appearance, flavor, softness, and overall acceptability, while color values appeared with the saddle points. The result also indicated that the level of the saltwort deviating more or less from the optimal amount reduced the preference for the product. Integration of the optimum responses common to all dependent variables that overlapped all the contour maps finally indicated that the combination of 8.3${\sim}$13.8 g saltwort, 2.5${\sim}$6.6 g salt, and 486.5${\sim}$511.5 g wheat flour under the selected preparation recipe optimized the physical and sensory properties in the teamed foam cakes. Practical preparation of the product with median amounts of the ingredients, i.e., 11.0 g saltwort, 4.6 g salt, and 499.0 g wheat flour resulted in similar qualities to the predicted responses. In conclusion, these study results indicated that preparation of steamed foam cake with added saltwort ingredient could potentially produce a more nutritious product with less salt. Further research is required to acquire the optimum levels for sub-ingredients to improve the product quality.