• Journal of Community Nutrition
• /
• v.8 no.4
• /
• pp.185-192
• /
• 2006

This study was performed to investigate factors affecting sensitivity and preference for salty tastes of Korean adult females. Sensitivity and preference for salty tastes were determined as detection threshold concentration of NaCl solution and the optimally-preferred NaCl concentration of the bean sprout soup, respectively. A self-administered questionnaire was used to obtain the information regarding general characteristics, self diagnosis of stress, health-related lifestyle practices, dietary habits and food preferences. Dietary intake using 24-hours recall and blood pressure were measured. Salty taste detection thresholds and optimally-preferred NaCl concentrations were 0.0197% and 0.357%, respectively. There was a significant positive correlation between the optimally-preferred salt concentration and age, despite no significant correlation between either sensitivity or preference for salty taste and sodium intake, which was 3,605mg/day. Those who had bread or cereal with milk as breakfast instead of a traditional Korean meal and those who preferred jjigae to soup had significantly higher NaCl preferences for bean sprout soup. Going to bed after midnight and skipping meals (${\geq}3/week$) decreased salty taste sensitivity without reaching statistical significance. Self awareness of one's own health, recent weight changes, family history of hypertension, sleep quality, getting-up time, rate of eating and other food preferences did not affect either perception. Stress level, TV watching, BMI and sodium intake did not have significant correlation to sensitivity or preference. Further research including a large number of well-controlled subjects and more accurate measurement of sodium intake should be directed to find other factors affecting salt preference and sensitivity in order to decrease Na intake and related diseases.

• The Korean Journal of Food And Nutrition
• /
• v.31 no.1
• /
• pp.94-103
• /
• 2018

The quality characteristics of bread with black rice flour were investigated to find the most preferred ratio of black rice flour. Its moisture, ash content, crude protein, crude fat, amino acids, and texture were analyzed. A sensory evaluation was also performed. The moisture and crude fat of bread with black rice flour were decreased in proportion to the added amount of black rice flour, but the crude protein and ash content were increased. The volume of bread decreased as the added amount of black rice flour increased. The pH value of bread increased in proportion to the added amount of black rice flour. The value of brightness and yellowness of the dough were the highest in the control. The added amount of black rice flour was negatively correlated with the brightness and the yellowness of the dough, but was positively correlated with the redness. Total free amino acids were found, and the dough with 5% black rice flour contained the highest amount, followed by 3%, 2%, and 1%. When evaluating the storage days, the springiness and cohesiveness of bread with black rice flour they decreased with time, but the chewiness and brittleness increased. Regarding the taste, preference was given to the bread with 2% black rice flour, which had the lowest rejection rate and was not affected by time in any meaningful sense. The bread with 2% black rice flour won the highest scores in the overall preference measurement.

• Management Science and Financial Engineering
• /
• v.10 no.1
• /
• pp.25-41
• /
• 2004

There have been many studies to build a model that can help investors construct optimal portfolio. Most of the previous models, however, are based upon the path-breaking Markowitz model (1959) which is a quantitative model. One of the most important problems with that kind of quantitative model is that, in reality, most of the investors use not only quantitative, but also qualitative information when they select their optimal portfolio. Since collecting both types of information from the markets are time consuming and expensive, making a set of target assets smaller, without suffering heavy loss in the rate of return, would attract investors. To extract only desired assets among all available assets, we need knowledge that identifies investors' preference for the risk of the assets. This study suggests two-layer decision-making rules capable of identifying an investor's risk preference and an architecture applying them to a quantitative portfolio model based on risk and expected return. Our knowledge-based portfolio system is to build an investor's preference-oriented portfolio. The empirical tests using the data from Korean capital markets show the results that our model contributes significantly to the construction of a better portfolio in the perspective of an investor's benefit/cost ratio than that produced by the existing portfolio models.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.14 no.4
• /
• pp.66-73
• /
• 2006

This study focuses on the economies of launching regular air services between capital cities of South Korea and North Korea. The demand for traveling between these two cities is too small to justify scheduled air service. However, it may be possible to provide regular air service by utilizing via flight of incumbent Seoul-Beijing flights. There are numerous flight services between Seoul and Beijing and we may allow some of the Seoul-Beijing flights to stop by Pyung Yang for commercial traffic handling. This study tries to find the optimal discount rate which passengers traveling between Seoul and Beijing via Pyung Yang, the idea is reasonable considering the inconvenience of stopping at Pyung Yang. The Stated Preference Techniques are applied for the study. The required data were collected through interviews of passengers traveling from Seoul to Beijing. The major variables that are considered in flight choice are air fare, flying time, and flight frequency. The relative importance of these major variables is estimated by the logit models calibrated with stated preference data.

• Journal of Broadcast Engineering
• /
• v.21 no.2
• /
• pp.210-218
• /
• 2016

In this study VOD usage patterns(VOD use and paid amount) of IPTV users were investigated reflecting the level of media use characteristics such as TV viewing time, star preference, and genre preference. Also the impact of media using characteristics and the evaluation of guide channel on the intention to use VOD was analyzed. The web survey was conducted against the respondents who have used VOD and guide channel. The results are as follows. Among the media usage characteristics, star preference has the impact on the VOD use, while genre preference has relation to the willingness to pay for VOD. Secondly, the intention to view the guide channel, entertainment of the channel, and the users' genre preference have significant impacts on the intention to use VOD. Therefore, it is necessary to raise the viewing rate of guide channel by providing the customized promotion strategy and diverse events based on the analysis of VOD usage.

• Korean Journal of Agricultural Science
• /
• v.50 no.3
• /
• pp.549-554
• /
• 2023

The traditional oviposition ground for indoor breeding of Luciola lateralis is moss. This study was conducted to find the most suitable alternative oviposition ground that can maintain or increase the oviposition rate of L. lateralis while addressing the problems of larva collection time and larva loss that occur when moss is used. As alternative candidate oviposition ground comprising six colors of non-woven fabric and felt were used to measure the fecundity variation rate of L. lateralis with respect to the color and material of the oviposition ground. In addition, measure the fecundity variation rate of L. lateralis in moss, a traditional oviposition ground, was also measured and investigated for comparison. The investigation showed that the average number of eggs in the non-woven fabric group was higher than that in the felt group. The yellow non-woven fabric had an average number of eggs that was more than 100 times higher than of moss used as a traditional oviposition ground. In the space where the six color non-woven fabric were together, L. lateralis concentrated its oviposition on yellow. These results showed that yellow non-woven fabric can be sufficiently used for efficient indoor mass breeding of L. lateralis while addressing problems caused by moss, a traditional oviposition ground.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.6
• /
• pp.1068-1076
• /
• 1997

This study was carried out to elucidate the utility of fusant for shortening the ripening time of imitation processed cheese. L. bulgaricus exhibited the highest protease and lactase activity and L. helveticus revealed the highest lipase activity. Fusant was shown to be high in the activity of protease and lactase. The total volatile free fatty acid produced by the cheese treated with L. helveticus was markedly increased after four ripening days and was gently increased after nine ripening days. However, L. bulgaricus significantly increased the total volatile free fatty acid between four and nine ripening days. In the case of fusant, the amount of total volatile free fatty acid was observed to increase at a constant rate relative to the ripening time. In free fatty acid production at different ripening times, L. bulfaricus generated caproic acid and caprilic acid abundantly while it produced a poor quantity of capric acid, lauric acid, and myristic acid. In the cheese sample treated with L. helveticus, the amount of caproic acid and capylic acid was on increase as the ripening time increased. The amount of caproic acid and caprylic acid produced by fusant was less than that produced by the other two starters. In the panel sensory evaluation, the flavor intensity and preference increased as the ripening time increased. The cheese sample treated with fusant showed the highest flavor intensity at 7 days, whereas cheese treated with L. helveticus exhibited the highest flavor intensity at 15 or 30 days. The cheese treated with L. helveticus showed the highest preference at 7 days, but cheese treated with fusant exhibited the highest preference at 30 days.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.20 no.1
• /
• pp.26-33
• /
• 2012

Competition between air transportation and railways has grown fiercer in major countries around the world with the rise of high-speed railways. In South Korea, air passenger travel has been rapidly decreasing since the initial launch of the Seoul-Pusan KTX line in 2004 and second opening that followed in 2010. Further expansion of the high-speed railway is expected. At present, research efforts to verify the validity of constructing an underwater express railway tunnel between Ho-nam and Jeju Island are taking place. Considering the possible high speed railway connection between Seoul and Jeju Island, this thesis has analyzed the choice behavior of existing passengers of the major and low-cost carriers. For this, Stated Preference (SP) research has been performed for three variables, including fare, travel time and the number of runs, to estimate the substitution rate of each of the three variables. Binomial Logit Model has been estimated with the obtained data. The estimation of the model has found that airline passengers of major and low-cost carriers are willing to pay approximately 7,200 KRW and 5,000 KRW, respectively, to reduce travel time by one hour. If the number of runs in one day increases, it has been estimated that the passengers are willing to pay additional fares of about 390 KRW and 30 KRW, respectively. On the other hand, the substitution rate between the number of runs and the travel time was found to be somewhat insignificant. If the construction of the Seoul-Jeju line progresses in the future, this study could be used as preliminary data for determining fares, travel time and the number of runs.

• Journal of Digital Convergence
• /
• v.17 no.1
• /
• pp.319-325
• /
• 2019

The 'Dinosaur Experience' exhibition at the Lasko exhibition hall hosted by Gwangmyeong city is gaining popularity. The purpose of this study is to analyze the elements of experience exhibition and interactive media experience exhibition and to grasp the preference of visitors. First, the theoretical review about interactive media and experience exhibition was made through literature data. Next, based on the Strategic Experience Module, we divided the experiential factors according to experiential value. As a result of the study, it was found that the participation rate of the visitors and the experience time were longer in the program containing many experience exhibition elements. Interactive media experience exhibited by many people have more value items. But it is not enough to understand the preference of visitors by the time spent by visitors. This study suggests that interactive media can be utilized for various experience exhibition.

• Convergence Security Journal
• /
• v.19 no.2
• /
• pp.73-81
• /
• 2019

In this paper, we propose a user-dependent mid-point navigation system using a time weighted mid-point navigation algorithm and a user preference based mid-point neighborhood recommendation system. The proposed system consists of a mid-point navigation module for calculating an mid-point by applying a time weight of each user based on a departure point between users, and a search module for providing a search for a route to the calculated mid-point. In addition, based on the mid-point search result, it is possible to increase the utilization rate of users by including a place recommending function based on user's preference. Experimental results show that the proposed system can increase the efficiency of using by the user-dependent mid-point navigation and place recommendation function.