• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.22 no.3
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• pp.179-199
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• 2018

The paper explores a tri-trophic food chain model with density dependent mortality of intermediate predator. To analyze this aspect, we have worked out the local stability of different equilibrium points. We have also derived the conditions for global stability of interior equilibrium point and conditions for persistence of model system. To observe the global behaviour of the system, we performed extensive numerical simulations. Our simulation results reveal that chaotic dynamics is produced for increasing value of half-saturation constant. We have also observed trajectory motions around different equilibrium points. It is noticed that chaotic dynamics has been controlled by increasing value of density dependent mortality parameter. So, we conclude that the density dependent mortality parameter can be used to control chaotic dynamics. We also applied basic tools of nonlinear dynamics such as Poincare section and Lyapunov exponent to investigate chaotic behaviour of the system.

• Journal of Information Technology Services
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• v.20 no.6
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• pp.1-16
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• 2021

The health functional food market continues to grow, and according to that trend, the subdivision sales of personalized health functional foods, which have been legally prohibited, will be operated as a special regulatory pilot project. Personalized health functional food recommendations have a variety of personalized indicators to consider, and it is believed that algorithmic methods will be needed to proceed in a customized manner considering all of them. This study aims to contribute to the development of the AI-based health functional food recommendation service by studying factors that affect the use of the AI-based health functional food recommendation service. This paper analyzed the intention of use for AI-based health functional food recommendation service based on the information system success model and Technology Acceptance Model. This study considered information quality factors, service quality factor, and system quality factor as independent variables influencing perceived usefulness, perceived ease of use and trust. For empirical analysis, 406 questionnaires were used and the collected data were performed using AMOS 22.0 and SPSS 22.0. Research has shown that the accuracy, timeliness, empathy and availability have a positive effect on usefulness. Understandability and availability has been shown to have a positive effect on ease of use. The accuracy, understandability, empathy and availibility has been shown to have a positive impact on Trust. Usefulness, ease of use and trust all have been shown to have a positive influence on intention of use.

• Journal of Korea Society of Digital Industry and Information Management
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• v.20 no.2
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• pp.159-174
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• 2024

Recently, as demand for delivery services has increased rapidly due to COVID-19, the food service O2O(Online to Offline) platform has also grown significantly. This study aimed to verify the influencing factors on continuance use intention of O2O platform using the Information Service Success Model and Post Acceptance Model. An online survey was conducted on 379 consumers who used the food service O2O platform in the past six months, and the collected survey was analyzed using SPSS 26.0 and AMOS 24.0. As a result of the verification, in the influence relationship between the Information Service Success Model and Post Acceptance Model, system quality was found to have an effect on perceived usefulness, but information quality and service quality were rejected for perceived usefulness and were partially adopted, The rest were all found to have a significant effect. In the moderating effect according to the amount used, the intention to continue using was stronger when the group who spent more than 30,000 won was satisfied. These results support previous research on O2O platforms and provide academic implications as well as practical implications for practitioners in the food service industry.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.165-175
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• 2021

Groundwater is used in many areas in food industry such as food manufacturing, food processing, cooking, and liquor industry etc. in Korea. As groundwater occupies a large portion of food industry, it is necessary to predict deterioration of water quality to ensure the safety of food water since using undrinkable groundwater has a ripple effect that can cause great harm or anxiety to food users. In this study, spatiotemporal data aggregation method was used in order to obtain spatially representative data, which enable prediction of groundwater quality change in a small watershed. In addition, a highly reliable predictive model was developed to estimate long-term changes in groundwater quality by applying a non-parametric segmented regression technique. Two pilot watersheds were selected where a large number of companies use groundwater for food water, and the appropriateness of the model was assessed by comparing the model-produced values with those obtained by actual measurements. The result of this study can contribute to establishing a customized food water management system utilizing big data that respond quickly, accurately, and preemptively to changes in groundwater quality and pollution. It is also expected to contribute to the improvement of food safety management.

• Journal of Environmental Health Sciences
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• v.42 no.3
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• pp.160-168
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• 2016

Objectives: Materials coming into contact with food may result in the migration of chemical substances into the food. To protect consumers from exposure, Regulation (EU) No. 10/2011 specifies the use of standard migration tests. Polyethylene terephthalate (PET), widely used for food packaging materials, has drawn the attention of researchers because unwanted migration of PET into food might occur when consumers reuse packaging material. The aim of this study was to predict and develop a migration model for two components, acetaldehyde and butyraldehyde in PET, into food simulants under conditions of changing pH and solvents, such as those observed in fermented foods like kimchi or sauerkraut. Methods: Using a migration model based on Fick's second law of diffusion in one dimension, the migration of acetaldehyde and butyraldehyde from PET into a simulant of fermented food at $20^{\circ}C$ over 10 days was evaluated. The simulant for fermented food was modelled as 10% ethanol for three days, followed by 3% acetic acid for seven days. Results: The migration of acetaldehyde into the 10% ethanol was 0.36 times that of a simulated fermented food system, while that of butyraldehyde was 1.34 times greater. These results may have been influenced by the chemical interactions among the migrants, polymers and simulants, as well as by the solubilities of the migrants in polymers and simulants. Conclusion: Because food simulants have a limited capacity to mimic real food systems under the current migration model, an appropriate simulant and migration test should be considered in the case of increasing acidity. Furthermore, since the accuracy of the worst-case estimation of migration predicted by the current model is severely limited under changing food conditions, food simulants and their interactions should be further investigated with respect to conservative migration modelling.

• Journal of the Korean Society of Food Culture
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• v.33 no.5
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• pp.426-436
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• 2018

This study assessed effective strategies to reduce the sodium intake among consumers using pork cutlet sauce as a model food system. Original pork cutlet sauce and sodium-reduced sauce (29% reduced by a salt substitute) were analyzed to characterize the sensory properties using descriptive analysis. The effects of sodium-reduction of the sauce, consumer type (nutrition teachers vs. general consumers), information related to the sodium content, serving method, and consumer's health, taste and sodium-related attitudes on the consumer's preference, perception, and intake of the sauce were analyzed using a consumer test. In descriptive analysis, the original and sodium-reduced sauce showed similar sensory characteristics but did not differ in saltiness. In the consumer test, there were no significant differences in the overall preference levels between the two sauces. On the other hand, there were significant differences in preference and perception between nutrition teachers and general consumer groups, which were due largely to their age as well as the health and sodium-related attitudes and nutritional knowledge differences. Sodium-reduced information decreased the perceived saltiness intensity. In addition, reducing sodium intake by serving pork cutlet sauce in a bottle can be an effective strategy because this serving method increased the acceptance and induced the smaller intake of sauce.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.194-207
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• 2021

It is necessary to assess and manage the different elements of the marine ecosystem, such as climate change, habitat, primary and secondary production, energy flow, food web, potential yield, and fishing, to maintain the health of the ecosystem as well as support sustainable development of fishery. We set up an ecosystem model around the Korean peninsula to produce scientific predictions necessary for the assessment and management of marine ecosystems and presented the usability of the model with scenario experiments. We used the Atlantis ecosystem model based on the marine food web; Atlantis is a three-dimensional end-to-end model that includes the information and processes within an entire system, from an abiotic environment to human activity. We input the ecological and biological parameters, such as growth, mortality, spawning, recruitment, and migration, to the Atlantis model via functional groups using existing research and local measurements. During the simulation period (2018-2019), we confirmed that the model reproduced the observed data reasonably and reflected the actual ecosystem characteristics appropriately. We thus identified the usability of a marine ecosystem model with experiments on different environmental change scenarios.

• The Korean Journal of Food And Nutrition
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• v.34 no.2
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• pp.242-253
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• 2021

The purpose of this study was to investigate the sustainable practices of nutrition science teachers and dietitians working in school food service operations, and identify the social and psychological factors which affect the overall efficacy of the system. The research model was constructed based on the Extended Theory of Planned Behavior (ETPB) in order to analyze how individual motivation affects the sustainable practices of nutrition science teachers and dietitians. The data were collected through e-mail and postal mail from nutrition science teachers and dietitians all across Korea, and self-administered surveys were conducted. SPSS and AMOS programs were used for statistical analysis. First, the sustainable practices of nutrition science teachers and dietitians were analyzed in 6 different categories. Second, the significant pathways were 6 out of 9 in the ETPB model. Sustainable food service practices in school can contribute to the formation of more a sustainable culture, such as through the encouragement of more healthy eating habits, and higher level of environmental awareness and community awareness. The factors influencing these practices can be applied to the design of improvement programs aimed at increasing sustainable practices.

• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.680-686
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• 2023

Aging is a complex series of multi-organ processes that occur in various organisms. As such, an in vivo study using an animal model of aging is necessary to define its exact mechanisms and identify anti-aging substances. Using Drosophila as an in vivo model system, we identified Crataegus pinnatifida extract (CPE) as a novel anti-aging substance. Regardless of sex, Drosophila treated with CPE showed a significantly increased lifespan compared to those without CPE. In this study, we also evaluated the involvement of CPE in aging-related biochemical pathways, including TOR, stem cell generation, and antioxidative effects, and found that the representative genes of each pathway were induced by CPE administration. CPE administration did not result in significant differences in fecundity, locomotion, feeding amount, or TAG level. These conclusions suggest that CPE is a good candidate as an anti-aging food substance capable of promoting a healthy lifespan.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2001.11a
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• pp.114-114
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• 2001