• Journal of Korea Port Economic Association
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• v.27 no.2
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• pp.1-26
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• 2011

This study was conducted to select the location of the logistics center for environment-friendly agricultural products in the Gwangyang Bay Area. AHP(Analytic Hierarchy Process) technique was used to examine location selection factors and factor hierarchy was made through a questionnaire survey and an expert interview for objective and quantitative decision. The hierarchy process of location factors of logistics center for environment-friendly agricultural products in the Gwangyang Bay Area were categorized into five factors such as natural factors, economic factors, social factors, distribution efficiency, and land use plan. Then, those factors were sub-categorized into three factors each. As a result of pair-wise comparison analysis of five categories, the weight of economic factors was the highest, and easy cargo transportation, fitness to higher-order plan, climate, land price, and limitation regulations of sub-categorized factors appeared as comparative evaluation criteria. The priority of the final candidate was decided through this process. While the weight of the Yulchon II Industrial Complex was the highest in natural and economic factors were the highest, the weight of the Gwangyang Hwanggeum Industrial Complex was the highest in social factors, distribution efficiency, and land use plan. The result of the final analysis showed that the Gwangyang Hwanggeum Industrial Complex was the most optimal location candidate for the logistics center for environment-friendly agricultural products.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.168-175
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• 2021

The optimal determination of seeding rate is critical to minimizing uncertainties about the large variations observed in forage quality and productivity when alfalfa is cultivated under different geographical areas and growing conditions. The objective of this investigation was to provide information about the proper seeding rate according to harvest timing for alfalfa cultivation in the Northern regions of Korea. Alfalfa was sown in September 2018 at a seeding rate of 20, 30 or 40 kg/ha and harvested four times in 2019: May 3, July 2, September 11, and October 13. Regardless of seeding rate, alfalfa plant height was longest at the third harvest (113 cm) and the shortest in the last annual harvest (43.8 cm). However, seeding rate had no effect on alfalfa plant height at any harvest. Forage relative feed value was increased in the first cutting but decreased in the third cuttings as seeding rate increased. However, seeding rate had slight effect on alfalfa forage quality components at the second and fourth cuttings. Total annual DM and crude protein production (in 4 harvests) was greater at higher seeding rates. Plots seeded at a rate of 40 kg/ha produced on average 1,257 and 2,620 kg/ha more forage (DM basis) than those seeded at a rate of 30 or 20 kg/ha, respectively. Forage DM production at the first, second, third, and fourth harvests accounted for 36.1, 24.0, 27.1, and 12.8 % of total annual DM production, respectively. Overall, small differences were seen when alfalfa seeding rate was different but maximum forage DM production (in four harvests) was detected when seeding rate was 40 kg/ha. These data could be useful to the alfalfa growers by allowing them to make more accurate trade-offs between seed price and the expected magnitude of forage yield gains in order to select the best seeding rate.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.353-360
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• 2019

Trade credit is being used as a price discrimination strategy by the suppliers in order to increase the customer's demand. From the viewpoint of the customer, if delayed payment is allowed for a certain period of time from the supplier, the effect of reducing the inventory carrying cost will positively affect the customer's order quantity. Also, in deriving the economic order quantity(EOQ) formula, it is tacitly assumed that the customer's ordering cost is a fixed cost. However in many business transactions, the customer pays the freight cost for the transportation of his order and so, the customer's ordering cost contains not only a fixed cost but also a freight cost which is a function of the order size. Therefore, in this study, we analyzed the inventory model which considers that the customer's ordering cost contains not only a fixed cost but also a freight cost which is a function of the customer's order size when the supplier permits a delay in payments. For the analysis, it is also assumed that inventory is exhausted not only by customer's demand but also by deterioration. Investigation of the properties of an optimal solution allows us to develop an algorithm whose validity is illustrated using an example problem.

• The Journal of the Korea Contents Association
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• v.22 no.4
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• pp.118-129
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• 2022

The purpose of this report is to study a strategic model of promotion activities through various analysis and sales forecasting by selecting wearable products for domestic online companies and collecting sales data. For data analysis, various algorithms are used for analysis and the results are selected as the optimal model. The gradation boosting model, which is selected as the best result, will allow nine independent variables to be entered, including promotion type, price, amount, gender, model, company, grade, sales date, and region, when predicting dependent variables through supervised learning. In this study, the review values set as dependent variables for each type of sales promotion were studied in more detail through the ensemble analysis technique, and the main purpose is to analyze and predict them. The purpose of this study is to study the grades. As a result of the analysis, the evaluation result is 95% of AUC, and F1 is about 93%. In the end, it was confirmed that among the types of sales promotion activities, value-added benefits affected the number of reviews and review grades, and that major variables affected the review and review grades.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.5
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• pp.454-462
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• 2023

Flash lamp annealing (FLA) of metal nanoparticle (NP) ink has provided powerful strategies to fabricate high-performance electrodes on a flexible substrate because of its rapid processing capability (in milliseconds), low-temperature process, and compatibility with to roll-to-roll process. However, metal NPs [e.g., gold (Au), silver (Ag), copper (Cu), etc.] have limitations such as difficulty in synthesizing fine metal NPs (diameter less than 10 nm), high price, and degradation during ink storage and FLA processing. In this regard, organometallic ink has been proposed as a material that can replace metal NPs due to their low-cost (usually 1/100 times cheaper than metal nano inks), low-temperature processability, and high material stability. Despite these advantages, the fabrication of flexible electrodes through FLA treatment of organometallic compounds has not been extensively researched. In this paper, we experimentally guide how to determine the optimal conditions for forming electrodes on flexible substrates by considering material parameters, and flashlight processing parameters (energy density, pulse duration, etc) to minimize the difficulties that may arise during the FLA of organometallic ink.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.9
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• pp.429-442
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• 2017

This study was performed to investigate and analyze users' needs for m-health based prevention and intervention programs that are intended to improve the awareness of metabolic syndrome and promote health behaviors of college students. A questionnaire survey was conducted to 200 college students of 2 university in D city. Data were analyzed using descriptive statistics, t-tests, chi-square test with the SPSS Version 20.0. The result showed that users wanted customization of prescriptions and accurate measurement of health applications, and provided a positive feedback on information exchange between those who manage their health. The most preferred content was proper exercise methods, and the preferred gamification factors were goal-setting, compensation, and competition. The optimal price for wearable devices was between 10,000 to 50,000 won, and calorie consumption function was also preferred. Although users with experiences of wearable devices and health apps had a higher knowledge score pertaining to metabolic syndrome, there was no significant difference in the overall score. Concerning the health behaviors associated with lifestyles, individuals without the experiences of wearable devices and health apps showed a remarkably lower score. The research has a significance that it investigated and analyzed the contents needed for the development of effective moblie health based prevention and intervention programs targeting the population in their early adulthood. Therefore, based on the findings, we propose a rich and concrete follow-up study on the needs and characteristics of different user types by collecting a population with experiences of wearable devices, and a development of differentiated mobile health based prevention and intervention programs.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.241-254
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• 2011

Financial time-series forecasting is one of the most important issues because it is essential for the risk management of financial institutions. Therefore, researchers have tried to forecast financial time-series using various data mining techniques such as regression, artificial neural networks, decision trees, k-nearest neighbor etc. Recently, support vector machines (SVMs) are popularly applied to this research area because they have advantages that they don't require huge training data and have low possibility of overfitting. However, a user must determine several design factors by heuristics in order to use SVM. For example, the selection of appropriate kernel function and its parameters and proper feature subset selection are major design factors of SVM. Other than these factors, the proper selection of instance subset may also improve the forecasting performance of SVM by eliminating irrelevant and distorting training instances. Nonetheless, there have been few studies that have applied instance selection to SVM, especially in the domain of stock market prediction. Instance selection tries to choose proper instance subsets from original training data. It may be considered as a method of knowledge refinement and it maintains the instance-base. This study proposes the novel instance selection algorithm for SVMs. The proposed technique in this study uses genetic algorithm (GA) to optimize instance selection process with parameter optimization simultaneously. We call the model as ISVM (SVM with Instance selection) in this study. Experiments on stock market data are implemented using ISVM. In this study, the GA searches for optimal or near-optimal values of kernel parameters and relevant instances for SVMs. This study needs two sets of parameters in chromosomes in GA setting : The codes for kernel parameters and for instance selection. For the controlling parameters of the GA search, the population size is set at 50 organisms and the value of the crossover rate is set at 0.7 while the mutation rate is 0.1. As the stopping condition, 50 generations are permitted. The application data used in this study consists of technical indicators and the direction of change in the daily Korea stock price index (KOSPI). The total number of samples is 2218 trading days. We separate the whole data into three subsets as training, test, hold-out data set. The number of data in each subset is 1056, 581, 581 respectively. This study compares ISVM to several comparative models including logistic regression (logit), backpropagation neural networks (ANN), nearest neighbor (1-NN), conventional SVM (SVM) and SVM with the optimized parameters (PSVM). In especial, PSVM uses optimized kernel parameters by the genetic algorithm. The experimental results show that ISVM outperforms 1-NN by 15.32%, ANN by 6.89%, Logit and SVM by 5.34%, and PSVM by 4.82% for the holdout data. For ISVM, only 556 data from 1056 original training data are used to produce the result. In addition, the two-sample test for proportions is used to examine whether ISVM significantly outperforms other comparative models. The results indicate that ISVM outperforms ANN and 1-NN at the 1% statistical significance level. In addition, ISVM performs better than Logit, SVM and PSVM at the 5% statistical significance level.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1125-1132
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• 2013

In the kimchi manufacturing process, the starter is cultured on a large-scale and needs to be supplied at a low price to kimchi factories. However, current high costs associated with the culture of lactic acid bacteria for the starter, have led to rising kimchi prices. To solve this problem, the development of a new medium for culturing lactic acid bacteria was studied. The base materials of a this novel medium consisted of Chinese cabbage extract, a carbon source, a nitrogen source, and inorganic salts. The optimal composition of this medium was determined to be 30% Chinese cabbage extract, 2% maltose, 0.25% yeast extract, and $2{\times}$ salt stock (2% sodium acetate trihydrate, 0.8% disodium hydrogen phosphate, 0.8% sodium citrate, 0.8% ammonium sulfate, 0.04% magnesium sulfate, 0.02% manganese sulfate). The newly developed medium was named MFL (medium for lactic acid bacteria). After culture for 24 hr at $30^{\circ}C$, the CFU/mL of Leuconostoc (Leuc.) citreum GR1 in MRS and MFL was $3.41{\times}10^9$ and $7.49{\times}10^9$, respectively. The number of cells in the MFL medium was 2.2 times higher than their number in the MRS media. In a scale-up process using this optimized medium, the fermentation conditions for Leuc. citreum GR1 were tested in a 2 L working volume using a 5 L jar fermentor at $30^{\circ}C$. At an impeller speed of 50 rpm (without pH control), the viable cell count was $8.60{\times}10^9$ CFU/mL. From studies on pH-stat control fermentation, the optimal pH and regulating agent was determined to be 6.8 and NaOH, respectively. At an impeller speed of 50 rpm with pH control, the viable cell count was $11.42{\times}10^9(1.14{\times}10^{10})$ CFU/mL after cultivation for 20 hr - a value was 3.34 times higher than that obtained using the MRS media in biomass production. This MFL media is expected to have economic advantages for the cultivation of Leuc. citreum GR1 as a starter for kimchi production.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.77-90
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• 2016

This study is to examine the importance of site selection and service quality in franchise business as food service franchise became one of the fastest-growing service industries today. The chief finding of this study is as follows: First, a survey in locational and service quality factors affecting food service franchise shows that responders are more concerned with hygiene and visibility of the store than proximity and transportation advantages which reflects low statistical significance, thus the distance did not seem to be a big problem for the responders in the context that they mostly visit nearby food franchise. Second, the examination of the influence by the service quality factors and customer satisfaction shows significant positive relation with customer response, speed and accuracy, and accuracy factors which reveals that the responders prefer prompt response and swift judgment toward the customer's needs and expectations, professional knowledge services to the credibility factors in which little correlation with the customer satisfaction were found. Third, the examination of the influence by the service quality factors, locational factors, and re-visit reveals that customer response and specialty showed statistically significant correlation with intention of WOM (Word of Mouth) and revisit, which suggests that swift judgment and response toward the customer's needs and expectations, professional knowledge services is of great importance to both customer satisfaction and revisit. The study on the aspects of locational and service quality factors affecting franchise industry's customer satisfaction was conducted as above, an investigation in both factors' influence on the customer satisfaction was made, and based on the results of the analysis, this research seeks an optimal operation strategy of a franchise business. Food service franchise are relatively very competent to business adminstration and reaction capability to consumption changes due to the already established market, and there are stores springing up everywhere inspired by the founders who are too confident of their success in the franchise business. However, it is necessary for the franchise beginners to figure out a zone oriented, regular customer oriented business strategy than just complying with the head office manual. Owing to an increasing trend of opening medium to large sized stores and investments in the wake of converting to multiple business type Korean food franchise, there is growing need to set up new concept of store development and operational management strategy in order to overcome the excessive competition and limited sales volume of the old-fashioned small sized, small capital franchise stores. Furthermore, as most business category of food service franchise serve very similar menus, from a product differentiation point of view, it is required to map out flexible sales concept including the adoption of competitive and low-price strategy. In conclusion, as is shown in the analytical research, the customers' optimal choice fluctuate over their preferences like customer convenience and circumstances rather than insisting on specific brand, thus it will be necessary for the franchise stores to draw up aggressive strategy and planning in running food service franchise to maximize their profits.

• Journal of Distribution Research
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• v.5 no.2
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• pp.49-68
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• 2001

In this chapter, we summarize the results on the optimal location selection and present limitation and direction of research. In order to reach the objective, this study selected and tested the interaction model which obtains the value of co-ordinates on location selection through the optimization technique. This study used the original variables in the model, but the results indicated that there is difference in reality. In order to overcome this difference, this study peformed market survey and found the new variables (first data such as price, quality and assortment of goods, and the second data such as aggregate area, and area of shop, and the number of cars in the parking lot). Then this study determined an optimal variable by empirical analysis which compares an actual value of market share in 1988 with the market share yielded in the model. However, this study found the market share in each variables does not reflect a reality due to an assumption of λ-value in the model. In order to improve this, this study performed a sensitivity analysis which adds the λ value from 1.0 to 2.9 marginally. The analyzed result indicated the highest significance with the market share ratio in 1998 at λ of 1.0. Applying the weighted value to a variable from each of the first data and second data yielded the results that more variables from the first data coincided with the realistic rank on sales. Although this study have some limits and improvements, if a marketer uses this extended model, more significant results will be produced.