• Journal of Platform Technology
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• v.6 no.4
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• pp.59-68
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• 2018

The objective of this study is to develop an embedded antenna structure with NFC and WPC composite functions. By selecting stable materials, the optimal component ratio of the polymer sheet was determined. The low cost embedded winding method compared to the existing FPCB was devised. During the winding process, characterization and process technology were developed. We also fabricated a ferrite mold to process the WPC grooves and developed the process technology for optimizing the WPC antenna. The following conclusions were obtained. (1) Optimum composition ratio was derived as Fe 87.5%, Si 7%, Al 5.5% and selected as the final material. (2) Optimal sheet conditions were derived from the experimental evaluation method and the experimental design method through the combination test of the optimized sheet and the conventional mass production FPCB. (3) According to coil diameter and inner diameter, Q value fluctuation, resistance value and efficiency fluctuation are obtained. Therefore, the most suitable coil condition is selected and Rx matching is performed. (4) The EMV load modulation test and the cognitive distance test of the polymer sheet and the ferrite sheet showed that the recognition distance of the polymer sheet at 1k and 4K was 32-33 mm and the recognition distance of the ferrite sheet at the same condition was 30-31 mm.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.194-210
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• 2013

Oiled paper (Yuji, 油紙) is an oil impregnated paper which was one of the daily necessities in Korea. As there has not been any accurate research on this subject, this study examined the literature from the Joseon Dynasty to study its origin, nomenclature, usage and production process. Goryeodogyeong (高麗圖經) and Goryeosa (高麗史) allowed the estimation that the origin of oiled paper was the Goryeo Dynasty, but the records of oil and paper in Samguksagi (三國史記) and Nihon Shoki (日本書紀) indicate the possibility that the production of oiled paper can be traced back to the 7th Century. The nomenclature and the usage of oiled paper in the Joseon Dynasty were examined through the Annals of Joseon Dynast (朝鮮王朝實錄), Ilseongnok (日省錄) and Seungjeongwonilgi (承政院日記), while the Royal Protocols of the Joseon Dynasty (Uigwe, 儀軌) and Takjijunjeol (度支準折) together with other literature were examined for its market value, use and materials. The literature from the Joseon Dynasty indicate that oiled paper was used for various everyday commodities with its waterproof, damp-proof and transparent properties and called in various ways according to its use and production process. This study studied the literature on oiled paper from the Joseon Dynasty, but the studies on the restoration of traditional oiled paper are still needed. Therefore, it would be necessary to study the traditional oiled papers in combination with the study of oiled paper relics, the reproduction of traditional oiled paper samples, and the case study of the papermaking masters who have been producing the traditional oiled papers.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.330-335
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• 2019

The aim of this study was to investigate the rheological properties of arabinogalactans (AGs) solution isolated from moth bean (MB), navy bean (NB), and soybean (SB) including monosaccharide compositions, intrinsic viscosity, steady shear and dynamic shear rheological properties. The major monosaccharides in MB, NB, and SB were arabinose (64.8, 51.4, and 42.6%) and galactose (13.4, 19.6, and 46.2%). The yield stresses for 5% (w/v) NB and 2.5% (w/v) SB solutions were assessed as 2.10 Pa and 1.98 Pa, respectively, but in case of MB solution, it was observed to be negligible. While 5% MB solution showed rheopectic property, 5% NB and SB solutions showed thixotropic properties. As a result of frequency sweep experiment, the G' values in 2.5% MB and NB were larger than the G" value showed but 2.5% SB exhibited G" value greater than G'. These results would be useful for future application as a food additive in the food industry.

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.193-199
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• 2019

Perilla seed oil is considered to be a rich source of omega-3 fatty acids and phenolic compounds, which have various health benefits. To improve its oil content and nutritional quality, 29 varieties of perilla have been bred, but their nutritional qualities, including the fatty acid and phenolic compound contents, have not been investigated. Therefore, in this study, the seed metabolite profiles, including the fatty acids, of these 29 perilla varieties were analyzed. Palmitic acid, stearic acid, linoleic acid, linolenic acid, rosmarinyl glucoside, and rosmarinic acid were identified as the major metabolites of perilla. The fatty acid contents were higher in the Okdong, Deulsaem, Daesil, Joim, Yeupsil, Danjo, and Joongmo5103 varieties (in order). However, the total phenolic compounds and antioxidative activities of Okdong and Deulsaem were relatively low, whereas the fatty acid and total phenol contents of Joim, Yeupsil, and Danjo were relatively high. These results may be useful for comparing the nutritional quality of the 29 perilla varieties.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.553-563
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• 2018

In this study, the location conditions and optimal technologies required for creating urban municipalities that can utilize the space in an abandoned mine area, where there is no infrastructure related to recycling wastes and valuable metals, are investigated. The urban mining industry deals with mineral resources through the processing of high value-added industrial by-products and wastes, and it is a useful linkage industry for the development of mineral resources and prevention of mining hazards. Urban mining technologies targeted at the abandoned mine area constitute screening, extraction, and smelting for recycling waste products. By analyzing the technologies available, an industrial network can be developed for recycling waste batteries and catalysts, which are promising raw materials. It is also important to establish an appropriate location for related industries that can generate value-added resources, rather than the resource supply and demand conditions seen in general urban mines. In order to overcome the accessibility and infrastructure limitations, the economic foundation of the abandoned mine area should consider the linkage of raw material supply, key technologies for recycling useful mineral resources that are derived from urban mines, spatial and site conditions, and industrial characteristics.

• Science of Emotion and Sensibility
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• v.24 no.3
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• pp.17-26
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• 2021

This study investigated the association between depression and oral health and the factors influencing depression in adults. Data on 13,199 people (male 5,793, female 7,406; age ≥19 years old) were extracted from the Korean National Health and Nutrition Examination Survey VIII (KNHANES VIII) (2016~2018) and analyzed using frequency, percentage, an x² test, a T-test, and logistic regression analysis. Depression was defined as either a medical diagnosis or a score ≥10 on Patient Health Questionnaire-9. The probability of depression was found to be statistically different for general characteristics, such as gender, age, school grade, income, and drinking. The logistic regression analysis showed that the independent variables, general health awareness (OR=9.094, 95% CI 7.139~11.585) and oral health awareness (OR=1.936, 95% CI 1.465~2.560), were associated with depression, and speaking discomfort, chewing discomfort, oral pain (within 1 year), and prosthesis were found to increase depression probability. The depression probability was also was found to significantly increase by 1.81 times if brushing frequency was less that once a day, if people used dental floss (OR=1.42), and had to have an oral examination (OR=1.31). These results indicated that oral health and oral health behaviors are associated with the depression, with the influencing factors having oral health and behavior-related characteristics. Therefore, proper oral health and oral health risk factor behavior management programs should be developed to assist in reducing depression.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.616-622
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• 2011

This study was conducted to investigate the effects of region and age on nut quality of major chestnut cultivars (Castanea spp.) cultivated in the central region of Korea to provide basic data for nut quality control and processing of postharvest. In the survey of by regions and ages, Buyeo and 'Hyogo57' showed the highest value by regions and cultivars, respectively. Also, there were statistically significant differences among regions and cultivars in the value of soluble solid content and kernel hardness. In the soluble solid content, Gongju showed the highest value among regions, and 'Tsukuba' among cultivars was the highest, 20.5%. Cheongyang showed the highest value of kernel hardness among regions, and 'Tanzawa' among cultivars showed the lowest value of kernel hardness, $8.75kg/cm^2$. In 'Tanzawa', 'Okkwang' and 'Tsukuba', soluble solid content and kernel hardness showed statistically significant differences according to age, but no correlation with age.

• Journal of Mushroom
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• v.18 no.4
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• pp.339-343
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• 2020

This study aimed to optimize total nitrogen (TN) content in the medium and the growth temperature to improve the shelf life of Pleurotus eryngii Keneutari No. 2. We investigated the growth characteristics and changes in the O2/CO2 content in polypropylene film and performed sensory evaluations during cold storage under 1.5%, 1.8%, 2.1%, and 2.4% TN and at temperatures of 9℃, 12℃, and 15℃. The diameter and weight of the fruit bodies tended to increase with increasing nitrogen content, regardless of the growth temperature, and the highest weight per bottle (149.5 g) was obtained at 12℃ and 2.4% TN. Regardless of the nitrogen content, leaf color deepened with decreasing temperature. The gas concentration in the film, which changes depending on storage time, was maintained for the longest period at 9℃ and 2.1% TN. The sensory evaluation revealed no difference between the different nitrogen conditions tested, and the odor, discoloration, and decay were similar at 15℃ and 9℃ until day 28 of storage.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.352-363
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• 2021

This study aimed to examine the different factors affecting the intention to purchase meal kits between at-home concept meal kits and eating-out concept meal kits. An online survey was conducted with 565 Korean participants including meal kit experienced (n=412) and non-experienced (n=153). Meal kits selection attributes were organized into five factors, health, price, environmental protection, convenience, and familiarity. To verify the hypothesis, SPSS Statistics 23 was used. The main results can be summarized as follows. First, in the case of the at-home menu, convenience(p < .01), environmental protection(p < .05), and familiarity(p < .01) show positive influences on willingness to buy. Second, for the eating-out menu, health(p < .001) and convenience(p < .001) have positive effects on willingness to buy, but familiarity(p<.01) has a negative effect. This is the first study to categorize the menu of meal kits and investigate each factor affecting willingness to buy. Therefore, the results can offer useful guidelines to meal kit marketers letting them know the consumers' purchase behaviors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.645-654
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• 2022

This study was conducted to prepare superheated steam roasted (SSR) small yellow croaker Larimichthys polyactis sweet potato salad (SPS) and tomato mousse (TM), as senior-friendly seafoods (SFS) and to examine their quality characteristics. The hardness values of SSR, SPS and TM were 110.5×1.0³, 22.4×1.0³ and 14.5×1.0³ N/m², respectively. The nutritional properties of SSR, SPS and TM were 22.4, 6.7 and 10.2 g/100 g, respectively, for protein, 97.01, 3.40 and 17.00 ㎍/100 g, respectively, for vitamin A, 10.26, 2.79 ㎍/100 g and not detected (ND), respectively, for vitamin D, 60.68 mg/100 g, ND and 4.17 mg/100 g, respectively, for vitamin C, 0.18, 0.10 and 0.33 mg/100 g, respectively, for riboflavin 24.28, 10.91 and 13.77 mg/100 g, respectively, for niacin, 76.3, 53.0 and 48.5 mg/100 g, respectively, for calcium, 258.2, 231.3 and 145.2 mg/100 g, respectively, for potassium, and ND, 0.70 mg/100 g and ND, respectively, for dietary fiber. Escherichia coli was not detected in any of the products. These results suggested that the products should be classified as step 1 for SSR, step 2 for SPS and step 3 for TM based on the SFS standard of the Korean industrial standards. Moreover, the nutritional and physical properties of the foods were improved.