• 한국초등과학교육학회지:초등과학교육
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• 제38권3호
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• pp.375-386
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• 2019

This study explores how elementary school students construct food pyramid prediction models using scientific reasoning. Thirty small groups of sixth-grade students in the Kyoungki province (n=138) participated in this study; each small group constructed a food pyramid prediction model based on scientific reasoning, utilizing prior knowledge on topics such as biotic and abiotic factors, food chains, food webs, and food pyramid concepts. To understand the scientific reasoning applied by the students during the modeling process, three forms of qualitative data were collected and analyzed: each small group's discourse, their representation, and the researcher's field notes. Based on this data, the researcher categorized the students' model patterns into three categories and identified how the students used scientific reasoning in their model patterns. The study found that the model patterns consisted of the population number variation model, the biological and abiotic factors change model, and the equilibrium model. In the population number variation model, students used phenomenon-based reasoning and relation-based reasoning to predict variations in the number of producers and consumers. In the biotic and abiotic factors change model, students used relation-based reasoning to predict the effects on producers and consumers as well as on decomposers and abiotic factors. In the equilibrium model, students predicted that "the food pyramid would reach equilibrium," using relation-based reasoning and model-based reasoning. This study demonstrates that elementary school students can systematically elaborate on complicated ecology concepts using scientific reasoning and modeling processes.

• 한국초등과학교육학회지:초등과학교육
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• 제31권1호
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• pp.71-83
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• 2012

The purpose of this study was to explore ecological concepts, epistemological reasoning and reasoning processes through constructing 'food web and food pyramid' in ecology. We conducted classes which involved a 'food web and food pyramid' for $6^{th}$ grade students. Each class is constructed of small groups to do modeling and epistemological reasoning through communication. The researcher had videotaped and recorded each class and have made transcription about classes. We analysed patterns of 'food web and food pyramid models' and reasoning processes according to scientific epistemology using transcription data and student outputs. As a result, students represented phenomenon-based reasoning, relation-based reasoning and model-based reasoning in scientific epistemology from their modeling. Students usually did relation-based reasoning and model-based reasoning in food web which explains ecological phenonenon, while they usually did model-based reasoning in food pyramid which expects ecological phenomenon. Student's reasoning can be limited when they have misconception of scientific knowledge and are limited by fragmentary knowledge. This represents that students has to do relation-based reasoning and model-based reasoning is beneficial in their ecological model. It also suggests that students need to define correct-conception related to ecological modeling(food web, food pyramid).

• 한국식생활문화학회지
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• 제22권1호
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• pp.70-76
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• 2007

The purpose of this study was to measure the effects of food neophobia, nausea, and learned food aversion on food rejection and appetite. A total of 250 questionnaires were completed. Path analytic model was used to measure the relationships between variables. Results of the study demonstrated that the path analysis result for the data also indicated excellent model fit. The effects of food neophobia on nausea and food rejection were statistically significant. The effect of food neophobia on learned food aversion and appetite was not statistically significant. As expected, nausea had a significant effects on learned food aversion and appetite. Moreover, nausea played a perfect mediating role in the relationship between food neophobia and appetite. Nausea played a perfect mediating role in the relationship between food neophobia and learned food aversion. Learned food aversion played a partial mediating role in the relationship between nausea and appetite. Learned food aversion did not play a mediating role in the relationship between food neophobia and appetite. In conclusion, based on path analyses, a model was proposed of interrelations between variables. It should be noted that the original model was modified and should, preferably, be validated in future research.

• 한국식품위생안전성학회지
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• 제26권2호
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• pp.120-124
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• 2011

훈제연어의 L. monocytogenes에 대한 식중독 안전관리 방안 마련 및 위해평가 수행 등을 위하여 성장예측모텔을 개발하였다. 미생물 성장예측모델 개발 방법은 대상 식품 및 환경 조건에 따라 다양하며 통계적으로 유용한 모델을 사용하여야 하기에 본 연구에서는 미생물 성장예측모델 개발에 널리 사용되어 그 적용성이 검토된 Gompertz model과 Polynomial model equation을 이용하여 훈제연어의 L. monocytogenes 최대성장속도(SGR) 및 유도기(LT)에 관한 예측모텔을 개발하였다. 개발된 모델의 적합성 평가를 위해 $B_f$와 $A_f$ factor를 산출하였고 최대성장속도(SGR)의 경우 0.98, 1.06, 유도기(LT)의 경우 1.60, 1.63으로 나타나 유도기의 적합성이 최대성장속도에 비하여 떨어지는 것으로 확인되었다. 본 연구에서 개발된 훈제연어에서의 L. monocytogenes 성장속도에 관한 모텔은, 수산업, 특히 훈제연어 생산, 가공, 보관 및 판매업에 다양한 방면으로 활용 가능할 것으로 판단되며, 더욱 정확한 예측모텔 개발을 위해서는 다양한 변수에 따른 미생물의 성장패턴 변화 등에 관한 연구가 추가적으로 시행되어야 할 것으로 생각되어 진다.

• Preventive Nutrition and Food Science
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• 제16권4호
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• pp.364-369
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• 2011

Levels of carbon dioxide gas, a metabolite of microbial growth, have been reported to parallel the onset of microbial spoilage and may be used as a convenient index for a packaged food's shelf life. This study aimed to establish a kinetic model of $CO_2$ production from perishable food for the potential use for shelf life control in the food supply chain. Aerobic bacterial count and package $CO_2$ concentration were measured during the storage of seasoned pork meat at four temperatures (0, 5, 10 and $15^{\circ}C$), and their interrelationship was investigated to establish a mathematical model. The microbial growth at constant temperature was described by using model of Baranyi and Roberts. $CO_2$ production from the stored food could be explained by taking care of its yield and maintenance factors linked to the microbial growth. By establishing the temperature dependence of the microbial growth and $CO_2$ yield factor, $CO_2$ partial pressure or concentration in package headspace could be estimated to a limited extent, which is helpful for controlling the shelf life under constant and dynamic temperature conditions. Application and efficacy of the model needs to be improved with further refinement in the model.

• Food Science and Biotechnology
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• 제15권5호
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• pp.715-720
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• 2006

This study was performed to develop a predictive model for the growth kinetics of Listeria monocytogenes in tryptic soy broth (TSB) using a response surface model with a combination of potassium lactate (PL), temperature, and pH. The growth parameters, specific growth rate (SGR), and lag time (LT) were obtained by fitting the data into the Gompertz equation and showed high fitness with a correlation coefficient of $R^2{\geq}0.9192$. The polynomial model was identified as an appropriate secondary model for SGR and LT based on the coefficient of determination for the developed model ($R^2\;=\;0.97$ for SGR and $R^2\;=\;0.86$ for LT). The induced values that were calculated using the developed secondary model indicated that the growth kinetics of L. monocytogenes were dependent on storage temperature, pH, and PL. Finally, the predicted model was validated using statistical indicators, such as coefficient of determination, mean square error, bias factor, and accuracy factor. Validation of the model demonstrates that the overall prediction agreed well with the observed data. However, the model developed for SGR showed better predictive ability than the model developed for LT, which can be seen from its statistical validation indices, with the exception of the bias factor ($B_f$ was 0.6 for SGR and 0.97 for LT).

• 한국식품위생안전성학회지
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• 제26권1호
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• pp.25-30
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• 2011

본 연구에서는 식중독 예방과 식품의 안전성 확보 및 정량적 미생물 위해평가에 활용하기위하여, Gompertz model과 Baranyi model을 이용하여 샐러드용 신선채소에서 L. monocytogenes의 SGR에 관한 성징예측모델(SGR by Gompertz equation=-0.1606+$0.0574^*Temp$+$0.0009^*Temp^*Temp$, SGR by Baranyi equation=0.3502-$0.0496^*Temp$+$0.0022^*Temp^*Temp$)을 개발하였다. 개발된 모델의 적합성 평가를 위해 MSE, Bf, 및 Af factor를 산출하였다. 샐러드용 신선 채소의 MSE, Bf, Af는 Gompertz model식을 적용한 경우 0.002718, 1.050084, 1.160767, Baranyi model 식을 적용한 경우 0.055186, 1.931472, 2.137181으로 나타나 Gompertz model식을 적용하여 개발한 예측모델이 Baranyi model 식을 이용하여 개발한 예측모델에 비해 적합성이 높은 것으로 나타났다. Gompertz model식을 활용하여 본 연구에서 개발된 샐러드용 신선 채소에서의 L. monocytogenes 성장 예측모델은 신선 채소류를 생산, 가공, 보관 및 판매하는 산업체에서 널리 활용 가능할 것으로 판단되며, 더욱 정확한 예측모델 개발을 위해서는 pH 및 수분활성도 등 다양한 변수에 따른 미생물의 성장패턴 변화 등에 관한 연구가 추가적으로 시행되어야 할 것으로 생각되어 진다.

• Nutrition Research and Practice
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• 제6권4호
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• pp.357-365
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• 2012

This study was conducted to develop a construct model regarding the daily activities, emotional security provided by food, enjoyment of food, level of satisfaction with delivered food, and the quality of life of homebound seniors who benefitted from meal delivery programs. The data were analyzed by SAS 9.2 and the Structural Equation Model (SEM), which was created by Analysis of Moment Structure (AMOS) 5.0 packages. The reliability of the data was confirmed by an exploratory factor analysis and through a Cronbach's alpha coefficient, and the measurement model proved to be appropriate by a confirmatory factor analysis of the measurement model in conjunction with AMOS. The results of the correlations between all the variables showed significant positive correlations (P < 0.05). The path analysis demonstrated that the daily activities (P < 0.01) and the emotional security created by food (P < 0.05) had positive correlations with the foodservice satisfaction (P < 0.05), while the daily activities (P < 0.05), the sense of emotional security made by food (P < 0.05), and food enjoyment (P < 0.05) also presented significant positive correlations with the quality of life. However, the food service satisfaction was shown to directly, but not significantly, affect the quality of life. This revealed that the current meal delivery programs needed to be improved in several directions.

• 한국조리학회지
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• 제13권2호
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• pp.153-162
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• 2007

The purpose of this study was to examine the mediating role of nausea, learned food aversion, and appetite on the relationship between food neophobia and food rejection. A total of 250(122 healthy males and 128 healthy females) questionnaires were completed. Path analytic model was used to measure the mediating effect. Results of the study demonstrated that the path analytic result for the data also indicated excellent model fit. Furthermore, the mediating analysis indicated that the influence of food neophobia was mediated by mediator. The effect of food neophobia on appetite was perfectly mediated by nausea and learned food aversion. In the contests of general food rejection, the effect of food neophobia on food rejection was perfectly mediated by appetite. It should be noted that the original model was modified and should, preferably, be validated in future research.

• 동아시아식생활학회지
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• 제18권3호
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• pp.294-301
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• 2008

The purpose of this study was to analyze the effects of food neophobia on food choice motives, such as health concern, weight control, ethical concern, and vegetable consumption. A total of 290 questionnaires were completed. Moderated regression analysis was used to measure the moderating effects of food neophobia. Results demonstrated Model 3 to be the best fit, compared to Model 1 and Model 2. In Model 3, the effects of health concern and food neophobia on vegetable consumption were statistically significant (p<0.01). However, the effects of weight control and ethical concern on vegetable consumption were not statistically significant (p>0.05). As expected, the combination of health concern and food neophobia had a significant effect on vegetable consumption (p<0.05). However, weight control and food neophobia, and ethical concern and food neophobia had no significant effects on vegetable consumption (p>0.05). Moreover, health concern related to vegetable consumption was statistically significant at all levels of food neophobia, except, when level of food neophobia was high (p<0.001). In developing and testing moderated regression models, which integrate relationship among food neophobia, health concern, weight control, ethical concern and vegetable consumption in the future, this study may provide a deeper understanding of the complex relationship among vegetable consumption behavior-related variables.