• Journal of Nutrition and Health
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• v.52 no.4
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• pp.342-353
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• 2019

Purpose: The Dietary Reference Intakes for Koreans (KDRIs) suggest that the goal for the intake of sodium should be less than 2,000 mg, which is thought to be infeasible to achieve when eating the typical Korean diet. This study aimed to obtain the new intake goals for sodium with improved feasibility to achieve, and also to design optimized food intake patterns for Korean adults by performing linear programming. Methods: The data from a one day 24-hour dietary recall of the 2010 ~ 2014 Korea National Health and Nutrition Survey were used to quantify food items that Korean adults usually consumed. These food items were categorized into seven groups and 24 subgroups. The mean intakes and intake distributions of the food groups and the food subgroups were calculated for eight age (19 ~ 29, 30 ~ 49, 50 ~ 64, and over 65 years old) and gender (male and female) groups. A linear programming model was constructed to minimize the difference between the optimized intakes and the mean intakes of the food subgroups while meeting KDRIs for energy and 13 nutrients, and not exceeding the typical quantities of each of the food subgroups consumed by the respective age and gender groups. As an initial solution of the linear programming, the optimized intake of seasonings, including salt, was calculated as 0 g for all the age and gender groups when the sodium constraint was inserted not to exceed 2,000 mg. Therefore, the sodium constraint was progressively increased by 100 mg until the optimized intake of seasoning was obtained as the values closest to the $25^{th}$ percentile of the intake distribution of seasonings for the respective age and gender groups. Results: The optimized food intake patterns were mathematically obtained by performing linear programming when the sodium constraint values were 3,600 mg, 4,500 mg, 4,200 mg, 3,400 mg, 2,800 mg, 3,100 mg, 3,100 mg, and 2,500 mg for the eight age and gender groups. Conclusion: The optimized food intake patterns for Korean adults were designed by performing linear programming after increasing the sodium constraint values from 2,000 mg to 2500 ~ 4,500 mg according to the age and gender groups. The resulting patterns suggest that current diets should be modified to increase the intake of vegetables for all the groups, milk/dairy products for the female groups, and fruits for the female groups except for the females aged 50 ~ 64 years.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.3
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• pp.60-70
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• 2019

Today, Deoksugung Doldam-gil, which is a well-known area in Seoul, has become a mixed place as many places reaching a critical age have been converted into parks. However, the previous research on the Deoksugung Doldam-gil was deficient in that the user, an essential variable, was not considered when assessing the place. Based on that, this study aims to analyze and interpret the perception of the places in Deoksugung Doldam-gil and to analyze factors to further enrich the place to visitors. According to the research, the representative idea of Deoksugung Doldam-gil is "the distance you want to go" and that has influencing factors, such as vehicle restrictions and the improvement of the walking environment. The analysis of classifying the variables that make up the perception of the place, physical environments, activities and meanings showed high awareness in, "streets of green (3.95)" and "stone walls of curves (3.88)." In the category of activities, "walking activities in the inner city (4.01)" and "love and romance (3.57)" were high. These results seem to reflect the spatial characteristics of the streets and the familiar image of the place were important. Five factors were extracted from the factor analysis to provide a more detailed understanding of the place perception, the correlation between each factor, and the place atmosphere of Deoksugung Doldam-gil. These factors confirmed a high correlation between 'green landscape' and 'historicity.' This can be attributed to the fact that the analysis reflects vital space, visual experience, and free walking conditions to be important, and these variables are present in urban parks. It also indicates the long-accumulated image and behavior near the site of Deoksugung Palace, including the historical and cultural heritage. It was confirmed that the factors related to the cognitive perception of Deoksugung Doldam-gil and the formation of the atmosphere of the place were strongly recognized. It found that there was a need to reflect the value and importance of 'green' in the future as culture or in the use of preservation and management related to heritage. This study presented a direction to be noted from the perspective of a user's place awareness, but considered only a fraction of the variables that affect the multidimensional sense of place and location recognition, and thus must be supplemented in the future.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.31 no.3
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• pp.101-114
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• 2019

In this study, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach, which is suffering from erosion problem. We obtain the basic equation (One Line Model for shoreline) for the numerical simulation by assuming that the amount of shoreline retreat or advance is balanced by the net influx of longshore and cross-shore sediment into the unit discretized shoreline segment. In doing so, the energy flux model for the longshore sediment transport rate is also evoked. For the case of cross sediment transport, the modified Bailard's model (1981) by Cho and Kim (2019) is utilized. At each time step of the numerical simulation, we adjust a closure depth according to pertinent wave conditions based on the Hallermeier's analytical model (1978) having its roots on the Shield's parameter. Numerical results show that from 2017.4.26 to 2017.10.15 during which swells are prevailing, a shoreline advances due to the sustained supply of cross-shore sediment. It is also shown that a shoreline temporarily retreats due to the erosion by the yearly highest waves sequentially occurring from mid-October to the end of October, and is followed by gradual recovery of shoreline as high waves subdue and swells prevail. It is worth mentioning that great yearly circulation of shoreline completes when a shoreline retreats due to the erosion by the higher waves occurring from mid-March to the end of March. The great yearly circulation of shoreline mentioned above can also be found in the measured locations of shoreline on 2017.4.5, 2017.9.7, 2017.11.7, 2018.3.14. However, numerically simulated amount of shoreline retreat or advance is more significant than the physically measured one, and it should be noted that these discrepancies become more substantial for the case of RUN II where a closure depth is sustained to be as in the most morphology models like the Genesis (Hanson and Kraus, 1989).

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.97-106
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• 2018

This study aimed at examining the suitability of $Tenax^{(R)}$ for the migration testing of food packaging materials, which is currently approved in the EU as a dry food simulant. The results are used as a basis to examine the feasibility of introducing $Tenax^{(R)}$ to Korean regulation. The OMVs of test specimen into various solvents (diethyl ether, ethanol, pentane, and acetone) after exposure to $100^{\circ}C$ for 1 hr were compared. Diethyl ether showed the highest OMV ($1.33mg/dm^2$) among the solvents tested. When the tests were conducted with different amounts of $Tenax^{(R)}$ of 2, 4, or 8 g per specimen, the OMVs were 0.75, 1.33 and $1.40mg/dm^2$, respectively. The OMV obtained with a closed system after wrapping with aluminum foil showed a significantly higher OMV ($1.61mg/dm^2$) than that without aluminum wrapping ($1.318mg/dm^2w$) and an open system without lid ($1.06mg/dm^2$). The specific migration rates of surrogates spiked in the polyethylene test film and paper samples into $Tenax^{(R)}$ were compared with those into liquid food simulants including 95% ethanol and n-heptane, and actual foods such as starch, skim milk, and sugar. In general, the specific migration levels of surrogates into $Tenax^{(R)}$ were similar compared with n-heptane, however those were significantly higher than into actual foods. These results suggest that $Tenax^{(R)}$ may be used as a food simulant for the long-term preservation of dried foods and paper products. However, more studies need to be conducted to investigate the factors influencing the migration into $Tenax^{(R)}$, such as the types of foods and packaging materials tested, migration conditions, and surrogates properties etc.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.438-446
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• 2018

The purpose of this study was to investigate food safety awareness, knowledge, and behavior in college students, to provide basic data for the increase in food safety awareness. Data were collected from 252 college students in Gyeonggi region, using a self-administered questionnaire. In results of concern about food safety, subjects responded 3.48 of 5.00 and have knowledge about food safety education revealing significantly higher awareness and concern than subjects without knowledge about food safety education. Food safety awareness of distributed food was 2.55, considered unsafe. Among reasons in perceiving food as unsafe, 62.3% of subjects expressed distrust about safety relative food production. As for risk factors relative to food safety, subjects responded that the highest risk factor was food additives (2.35), followed by heavy metal (2.38) and endocrine disrupters (2.38). Correlation analysis resulting in risk factors for food had positive correlation with each other, heavy metal revealed highest correlation with pesticide residue (r = 0.674), than with endocrine disrupters (r = 0.672). Also, genetically modified food revealed high correlation with radiation irradiated food. Regression analysis demonstrated that concern about food safety significantly influenced pro-actively engaging in food safety education. Meanwhile, 63.5% of subjects correctly responded to food safety knowledge items. The item 'the heavy metals are contaminated the most, in the roots of vegetables' revealed the lowest correct answer rate (38.1%). In food safety behavior, the item 'always wash hands before handling food and meal's revealed 3.85, and subjects with awareness and concern about food safety education, responded in significantly higher numbers than subject without awareness and concern about food safety. The most neglected concern was relative to frozen food thawed at room temperature. Together, students recognize that distributed foods are unsafe, and students with awareness and concern about food safety education showed higher knowledge compared to without awareness and concern experience about food safety eduction. So, systematic education using accurate and objective data is required to reduce anxiety and raise the level of awareness and concern about food safety.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1003-1012
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• 2018

This study is for checking the possibility of Lentinula edodes as cosmetic materials. For this we carried out biological active evaluation about anti-oxidant and anti-inflammatory effects by Lentinula edodes extracts. We extracted Lentinula edodes with water and 70% ethanol and then in order to evaluate anti-oxidant activity we treated samples by concentrations (100, 500, 1000) ${\mu}g/ml$ and carried out 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, the activity of 2,2'-azino-bis ( 3-ethylbenzothiazoline-6-sulphonic acid )-diammonium salt (ABTS) cation radical scavenging and superoxide dismutase(SOD) like activity. Also, in order to evaluate effect of anti-inflammatory the samples in macrophages(RAW 264.7 cells), we carried out evaluation of cell viability, nitric oxide inhibitory activity western blot. The results of DPPH, $ABTS^+$ radical scavenging activity and SOD-like activity of the Lentinula edodes extracts increased in dose-dependent manner. The cytotoxic of samples by MTT assay showed no toxicity at the concentrations of 10, 25 and $50{\mu}g/ml$ of Lentinula edodes extract. Nitric oxide inhibition activity results showed that the extracts reduced NO productions in a concentration-dependent manner. Expression of inflammatory cytokines as $TNF-{\alpha}$, $PGE_2$ and $IL-1{\beta}$ decreased in a concentration-dependent manner and iNOS and COX-2 proteins expression rates were decreased significantly in western blot analysis. From the results of the experiment, it was comfirmed that the Lentinula edodes extracts had excellent anti-oxidant and anti-inflammatory effect and could be used as a safe natural cosmetic material in the future.

• Journal of Climate Change Research
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• v.2 no.4
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• pp.283-295
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• 2011

Many actions against climate change have been taken to reduce greenhouse gases (GHGs) emissions at home and abroad. As of 2007, the GHGs emitted from buildings accounted for about 23 % of Korea's total GHGs emission, which is the second largest GHG reduction potential following industry. In this study, we introduced Carbon Zero Building (CZB), which was constructed by the National Institute of Environmental Research to cut down GHGs from buildings in Korea, and evaluated the main applied technologies, the amount of energy load and reduced energy, and economic values for CZB to provide data that could be a basis in the future construction of this kind of carbon-neutral buildings. A total of 66 technologies were applied for this building in order to achieve carbon zero emissions. Applied technologies include 30 energy consumption reduction technologies, 18 energy efficiency technologies, and 5 eco-friendly technologies. Out of total annual energy load ($123.8kWh/m^2$), about 40% of energy load ($49kWh/m^2$) was reduced by using passive technologies such as super insulation and use of high efficiency equipments and the other 60% ($74.8kWh/m^2$) was reduced by using active technologies such as solar voltaic, solar thermal, and geothermal energy. The construction cost of CZB was 1.4 times higher than ordinary buildings. However, if active technologies are excluded, the construction cost is similar to that of ordinary buildings. It was estimated that we could save annually about 102 million won directly from energy saving and about 2.2 million won indirectly from additional saving by the reduction in GHGs and atmospheric pollutants. In terms of carbon, we could reduce 100 ton of $CO_2$ emissions per year. In our Life Cycle Cost (LCC) analysis, the Break Even Point (BEP) for the additional construction cost was estimated to be around 20.6 years.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.297-305
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• 2018

Purpose: This study aimed to analyze stress distribution and maximum von Mises stress generated in intracoronal restorations and in tooth structures of mandibular molars with various types of cavity designs and materials. Materials and Methods: Three-dimensional solid models of mandible molar such as O inlay cavity with composite and gold (OR-C, OG-C), MO inlay cavity with composite and gold (MR-C, MG-C), and minimal invasive cavity on occlusal and proximal surfaces (OR-M, MR-M) were designed. To simulate masticatory force, static axial load with total force of 200 N was applied on the tooth at 10 occlusal contact points. A finite element analysis was performed to predict stress distribution generated by occlusal loading. Results: Restorations with minimal cavity design generated significantly lower values of von Mises stress (OR-M model: 26.8 MPa; MR-M model: 72.7 MPa) compared to those with conventional cavity design (341.9 MPa to 397.2 MPa). In tooth structure, magnitudes of maximum von Mises stresses were similar among models with conventional design (372.8 - 412.9 MPa) and models with minimal cavity design (361.1 - 384.4 MPa). Conclusion: Minimal invasive models generated smaller maximum von Mises stresses within restorations. Within the enamel, similar maximum von Mises stresses were observed for models with minimal cavity design and those with conventional design.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.11-19
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• 2018

This study was conducted to develop the manufacturing method of biochar using pruned stems of pear tree and its application effect on the crop growth and soil physico-chemical properties. In this study, biochar derived from pruned stems of pear tree at heating temperature of $300^{\circ}C$, $500^{\circ}C$ and $700^{\circ}C$ in heating times of 2, 3 and 4 hours, were tested in the changes of their chemical properties during biochar processing. The pH, Exch. K, Exch. Mg and cation exchange capacity (CEC) increased as the pyrolysis temperature increased during the production of biochar, and the change of these properties rapidly occurred at $500^{\circ}C$. However, as the pyrolysis temperature increased, ash content increased and total carbon (T-C), yield decreased. And the change of the properties in response to the heating time was not shown. It was thought that it would be desirable to set the production conditions of biochar at $500^{\circ}C$ for 2 hours in consideration of the change of chemical properties and the ash content and yield. And also, were conducted the experiments to establish manufacturing method of farm-made biochar using drum biochar manufacturing machine and investigate the application effects of biochar on the cultivation of chinese cabbage and tomato. Application of biochar derived from pruned stems of pear tree could enhance pH, organic matter (OM), total carbon (T-C) of soil. On the other hand, soil electrical conductivity (EC), NO3-N were lowered compared to the control which has no application. The bulk density, porosity and aggregate formation of soil were improved by biochar application. The fresh matter yields of chinese cabbage and tomato were significantly increased in proportion to the application rate of biochar. This study demonstrated the effect of the biochar derived from agricultural byproduct to be as a low cost potential soil ameliorant by physico-chemical properties in eco-friendly greenhouse cultivation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.224-230
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• 2018

This study was conducted to investigate the effects of concentrate feeding frequency on weight change and the colic of Jeju cross-bred horses. Around thirty-six old Jeju cross-bred horses were divided into three groups and were investigated by feeding the concentrate feed at 2.5% of their body weight 2 times, 3 times, or 4 times daily. Although the total weight gain and daily weight gain for the different feeding frequencies were higher with feeding concentrates 4 times daily compared with the other treatment groups, there was no statistically significant difference between the groups (p>0.05). Rectal temperatures were above the normal range in weeks 11 to 12, but there was no statistically significant difference between the groups (p>0.05). Fecal pH was below the normal range in weeks 1 to 12, but there were no colic symptoms with any of the treatments and there was no statistically significant difference between the groups (p>0.05). When feeding concentrate feed at 2.5% of body weight, it was assumed that trying to feed it several times per day would help to prevent colic; however, there was no difference in weight gain, blood characteristics, and physiological characteristics in accordance with the number of feeding times.