• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.3
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• pp.83-96
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• 2017

This study presented a surface water quality modeling framework considering the spatial resolution of pollutant load estimation to better represent stream water quality characteristics in the Saemangeum watershed which has been focused on keeping its water resources sustainable after the Saemangeum embankment construction. The watershed delineated into 804 sub-watersheds in total based on the administrative districts, which were units for pollutant load estimation and counted as 739 in the watershed, Digital Elevation Model (DEM), and agricultural structures such as drainage canal. The established model consists of 7 Mangyung (MG) sub-models, 7 Dongjin (DJ) sub-models, and 3 Reclaimed sub-models, and the sub-models were simulated in a sequence of upstream to downstream based on its connectivity. The hydrologic calibration and validation of the model were conducted from 14 flow stations for the period of 2009 and 2013 using an automatic calibration scheme. The model performance to the hydrologic stations for calibration and validation showed that the Nash-Sutcliffe coefficient (NSE) ranged from 0.66 to 0.97, PBIAS were -31.0~16.5 %, and $R^2$ were from 0.75 to 0.98, respectively in a monthly time step and therefore, the model showed its hydrological applicability to the watershed. The water quality calibration and validation were conducted based on the 29 stations with the water quality constituents of DO, BOD, TN, and TP during the same period with the flow. The water quality model were manually calibrated, and generally showed an applicability by resulting reasonable variability and seasonality, although some exceptional simulation results were identified in some upstream stations under low-flow conditions. The spatial subdivision in the model framework were compared with previous studies to assess the consideration of administrative boundaries for watershed delineation, and this study outperformed in flow, but showed a similar level of model performance in water quality. The framework presented here can be applicable in a regional scale watershed as well as in a need of fine-resolution simulation.

• Journal of the Korea Institute of Building Construction
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• v.16 no.2
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• pp.107-115
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• 2016

In this study, the bond strength of metal spraying system by surface treatment of concrete (waterproof/corrosion method) in water treatment facilities was evaluated. The results showed that the system with Sa-P-R-(S) (sanding-perviousness surface hardener-surface roughness agent-metal spraying-sealing) led to the desirable performance. The bond strength, the coefficient of water permeability and air permeability were 3.7MPa, $0.68{\ast}10^{-8}cm/sec$, and $0.45{\ast}10^{-16}m^2$, respectively. In scanning electron microscope analysis, the microstructure of specimen coated with perviousness surface hardener was much denser than that without it. Therefore, the specimen coated with sanding-perviousness surface hardener-surface roughness agent-metal spraying-sealing had the best bond performance and was the most suitable system to concrete surface in water treatment facilities.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.2
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• pp.125-132
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• 2016

Objectives : The management of disaster should be immediate and sustainable. Further, it is hard to predict where the disaster will occur, using pre-exists governmental and non-governmental organizations are important. In this study, we tried to investigate the associated activities of organizations performed in Ansan city, in Sewol ferry accident. Methods : A total 121 workers in 25 organizations were surveyd about organizations which they worked with, kind of works performed, frequency of meetings, satisfaction in activities and factors associated with dissatisfaction in usual state and in Sewol ferry accident state, respectively. The differences between those two situations were analyzed using paired t-test for continuous variables and Chi-square test or McNemar test for categorical variables. Results : The total number of linkage of institutions were decreased(from n=397 to n=251) and the mean scores of rating satisfaction were significantly lower in most of organizations in disaster state. The rigid policy in performance evaluation was more likely associated with dissatisfaction in disaster state than usual state(p=0.045). Conclusions : For effective linkage of institutions, preparedness, such as understanding the capability of organizations in the communities and developing the protocol for associated activities, is important. The unnecessary and effortful performance evaluation should be sublated.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.3
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• pp.69-75
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• 2019

The purpose of this study is to provide the conservation management direction about cultural landscape of the traditional villages in the area of Huizhou through the importance-performance analysis. The results of the survey on the importance - performance of 261 people who had many visits to various cultural landscapes of Huizhou villages such as Hongchun, Sidichun etc. are as follows. It was appeared that the item of 'good air' is the highest level of importance and satisfaction and is best condition. The item of 'historical conservation' is the high level of importance, but the level of satisfaction is low, so continuous improvement is necessary. The item of 'Old garden conservation' has high satisfaction but low importance, so it needs to improve its importance through subsequent improvement. The item of 'Keeping of old cemetary and old tower' has low importance and satisfaction but it is above average, so continuous maintenance is needed. The items of 'Preservation of stone gate' and 'Preservation of famous man's birth house' all have slightly higher satisfaction and lower importance. Both items are highly satisfied with their importance, so they should avoid excessive efforts and maintain the present status. Satisfaction with the item of 'water environment and water quality' was the lowest, and the problem of the present condition is the most serious, and a major improvement is needed. The importance and satisfaction of 'Commercial development of old villages' was the lowest among all items. This item is causing serious problems and should provide an overall improvement way to drastically improve the importance and satisfaction. Concentration is necessary to improve the environment of the whole villages, to protect the ecological plants and animals in old villages, to transfer and improve the culture of old villages, to maintain sustainability of the villages, and to protect old temple and old rock in old villages. As the level of satisfaction with sustainability is the lowest in the part of 'Concentrate here', there is a great concern about sustainability. Therefore, it is necessary to focus on sustainability and concentrate on sustainable development.

• Animal Bioscience
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• v.36 no.2
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• pp.218-228
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• 2023

Objective: This study investigated the effects of feeding anthocyanin-rich black cane treated with ferrous sulfate and molasses on animal performance, rumen fermentation, microbial composition, blood biochemical indices, and carcass characteristics in meat goats. Methods: Thirty-two Thai-native×Anglo-Nubian crossbred male goats (14.47±2.3 kg) were divided equally into two groups (n = 16) to investigate the effect of feeding diet containing 50% untreated anthocyanin-rich black cane silage (BS) vs diet containing anthocyaninrich black cane silage treated with 0.03% ferrous sulfate and 4% molasses (TBS) on average daily gain (ADG) and dry matter intake (DMI). At the end of 90 d feeding trial, the goats were slaughtered to determine blood biochemical indices, rumen fermentation, microbial composition, and carcass characteristics differences between the two dietary groups. Results: Goats fed the TBS diet had greater ADG and ADG to DMI ratio (p<0.05). TBS diet did not affect rumen fluid pH; however, goats in the TBS group had lower rumen ammonia N levels (p<0.05) and higher total volatile fatty acid concentrations (p<0.05). Goats in the TBS group had a higher (p<0.05) concentration of Ruminococcus albus but a lower (p<0.05) concentration of methanogenic bacteria. The TBS diet also resulted in lower (p<0.05) thiobarbituric acid-reactive substances concentration but higher (p<0.05) total antioxidant capacity, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase concentrations in blood plasma, while having no effect on plasma protein, glucose, lipid, immunoglobin G, alanine transaminase, and aspartate aminotransferase. Meat from goats fed the TBS diet contained more intramuscular fat (p<0.05) and was more tender (p<0.05). Conclusion: In comparison to goats fed a diet containing 50% untreated anthocyanin-rich black cane silage, feeding a diet containing 50% anthocyanin-rich black cane silage treated with 0.03% ferrous sulfate and 4% molasses improved rumen fermentation and reduced oxidative stress, resulting in higher growth and more tender meat.

• Earthquakes and Structures
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• v.24 no.6
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• pp.455-475
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• 2023

The present study investigates the non-linear soil-pile interaction using three-dimensional (3D) non-linear finite element models. The numerical models were validated by using the results of extensive pile load and shaking table tests. The pile performance in liquefiable and non-liquefiable soil has been studied by analyzing the liquefaction ratio, pile lateral displacement (LD), pile bending moment (BM), and frictional resistance (FR) results. The pile models have been developed for the different ground conditions. The study reveals that the results obtained during the pile load test and shaking cycles have good agreement with the predicted pile and soil response. The soil density, peak ground acceleration (PGA), slenderness ratio (L/D), and soil condition (i.e., dry and saturated) are considered during modeling. Four ground motions are used for the non-linear time history analyses. Consequently, design charts are proposed depended on the analysis results to be used for design practice. Eleven models have been used to validate the capability of these charts to capture the soil-pile response under different seismic intensities. The results of the present study demonstrate that L/D ratio slightly affects the lateral displacement when compared with other parameters. Also, it has been observed that the increasing in PGA and decreasing L/D decreases the excess pore water pressure ratio; i.e., increasing PGA from 0.1 g to 0.82 g of loose sand model, decrease the liquefaction ratio by about 50%, and increasing L/D from 15 to 75 of the similar models (under Kobe earthquake), increase this ratio by about 30%. This study reveals that the lateral displacement increases nonlinearly under both dry and saturated conditions as the PGA increases. Similarly, it is observed that the BM increases under both dry and saturated states as the L/D ratio increases. Regarding the acceleration histories, the pile BM was reduced by reducing the acceleration intensity. Hence, the pile BM decreased to about 31% when the applied ground motion switched from Kobe (PGA=0.82 g) to Ali Algharbi (PGA=0.10 g). This study reveals that the soil conditions affect the relationship pattern between the FR and the PGA. Also, this research could be helpful in understanding the threat of earthquakes in different ground characteristics.

• Information Systems Review
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• v.23 no.3
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• pp.51-75
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• 2021

Global e-commerce websites offer personalized recommendation services to gain sustainable competitiveness. Existing studies have offered personalized recommendation services using quantitative preferences such as ratings. However, offering personalized recommendation services using only quantitative data has raised the problem of decreasing recommendation performance. For example, a user gave a five-star rating but wrote a review that the user was unsatisfied with hotel service and cleanliness. In such cases, has problems where quantitative and qualitative preferences are inconsistent. Recently, a growing number of studies have considered review data simultaneously to improve the limitations of existing personalized recommendation service studies. Therefore, in this study, we identify review and rating mismatches and build a new user profile to offer personalized recommendation services. To this end, we use deep learning algorithms such as CNN, LSTM, CNN + LSTM, which have been widely used in sentiment analysis studies. And extract sentiment features from reviews and compare with quantitative preferences. To evaluate the performance of the proposed methodology in this study, we collect user preference information using real-world hotel data from the world's largest travel platform TripAdvisor. Experiments show that the proposed methodology in this study outperforms the existing other methodologies, using only existing quantitative preferences.

• Journal of the Korea Society of Computer and Information
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• v.29 no.3
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• pp.67-74
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• 2024

In this paper, we present a study aimed at analyzing how different rainfall measurement methods affect the performance of reservoir water level predictions. This work is particularly timely given the increasing emphasis on climate change and the sustainable management of water resources. To this end, we have employed rainfall data from ASOS, AWS, and Thiessen Network-based measures provided by the KMA Weather Data Service to train our neural network models for reservoir yield predictions. Our analysis, which encompasses 34 reservoirs in Jeollabuk-do Province, examines how each method contributes to enhancing prediction accuracy. The results reveal that models using rainfall data based on the Thiessen Network's area rainfall ratio yield the highest accuracy. This can be attributed to the method's accounting for precise distances between observation stations, offering a more accurate reflection of the actual rainfall across different regions. These findings underscore the importance of precise regional rainfall data in predicting reservoir yields. Additionally, the paper underscores the significance of meticulous rainfall measurement and data analysis, and discusses the prediction model's potential applications in agriculture, urban planning, and flood management.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.891-899
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• 2024

The Fourth Industrial Revolution is centered on a personalized demand fulfillment economy and is all about transformation and flexible processing that can deliver what customers want in real time across space and time. This paper implements the construction and operation of a packaging platform that can instantly procure the required packaging products based on real-time orders and evaluates its performance. The components of customer satisfaction are flexible and dependent on the situation which requires efficient management of enterprise operational processes based on an e-SCM platform. An OMS optimized for these conditions plays an important role in maximizing and differentiating the efficiency of a company's operations and improving its cost advantage. OMS is a system of mass customization that provides efficient MOT(Moment of Truth) logistics services to meet the eco-friendly issues of many individual customers and achieve optimized logistics operation goals to enhance repurchase intentions and sustainable business. OMS precisely analyzes the collected data to support information and decision-making related to efficiency, productivity, cost and provide accurate reports. It uses data visualization tools to express data visually and suggests directions for improvement of the operational process through statistics and prediction analysis.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.6
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• pp.167-187
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• 2020

Currently, Korea is changing into an ultra-aging society, and office workers retire at the age of 49.5 on average from their main jobs, and the national pension is delayed from 62 years old to 65 years old by 2034, so research is needed to prepare for the aging of office workers after retirement. The purpose of this study is to examine the factors affecting the intention to start a business after retirement and the mediating effect of another sense of success expectation on life after retirement, targeting office workers nationwide. Changes in individual attitudes and systematic institutional support are needed to prepare for a sustainable job until the age of 100 after retirement, that is, a start-up utilizing wisdom and experience in work life. As a result of the study, the ability to perform the goal as job performance, economic preparation for retirement preparation, preparation for external relations, and future anxiety have a positive effect on the entrepreneurial will, and the ability to use new technologies as job performance, and physical preparation for retirement. Preparation and preparation for internal relations were found to have no effect. In the influencing relationship between preparation for external relations and the will of start-up, and future anxiety and will of start-up, another sense of success was confirmed to have a partial mediation effect. In the relationship between economic preparation and willingness to start a business, the effect of complete mediation was confirmed. In order to increase the will to start a business after retirement, it was confirmed that another sense of expectation for success was an important variable. Introducing a government-sponsored education system in the company to reduce the government's financial burden due to super-aging and achieve corporate growth through employee training while potential founders, office workers, are employed, and entrepreneurship and goals for the three life goals of office workers By introducing a performance improvement program, we were able to get implications that would be a solution to the growth of individuals and businesses and reducing the government's financial burden.