• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.193-202
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• 1999

Al powder, AlN powder, SiC whisker and sintering aids were wet-mixed, and then the specimens prepared with mixed powder were reacted by nitridation at 600∼1400$^{\circ}C$ for 5 hrs. It was cleat that the higher nitridation and the more SiC whisker content were, the better bending strength was. The specimen of Al50/AlN50 reacted at 1400$^{\circ}C$ for 5hrs had the nitridation percent of 97%, the shrinkage under 2%, and the relative density of 78%. And the maximum bending strength of reaction-bonded specimen was 250 MPa. The specimens completely nitrided were post-sintered at 1700, 1800 and 1900$^{\circ}C$ for 2hrs. The post-sintered body had the shrinkage under 6% and the relative density of 86%. Because of the formation of solid solution between AlN and SiC whisker over 1800$^{\circ}C$, the promotion of mechanical properties according to SiC whisker addition was not observed. The post-sintered body had the maximum bending strength of 195 MPa.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.975-980
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• 2011

1-Palmitoyl-2-oleoyl-3-oleoyl glycerol (POO) and 1-palmitoyl-2-oleoyl-3-palmitoyl glycerol (POP) were enriched from palm stearin using an acetone fractionation process. Response surface methodology was employed to optimize the purity of POO ($Y_1$, %) and POP ($Y_2$, %) along with POO+POP content ($Y_3$, g) based on independent variables such as fractionation temperature ($X_1$, 25, 30, and $35^{\circ}C$) and the ratio of palm stearin to acetone ($X_2$, 1:3, 1:6 and 1:9, w/v). Fractionation conditions were optimized to maximize $Y_1$, $Y_2$, and $Y_3$, in which fractionation temperature was $29.3^{\circ}C$ with a 1:5.7 acetone ratio. With such parameters, 60.9% of POP and 23.8% of POO purity were expected with a 75% yield (3.0 g) of POO and POP.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1315-1319
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• 2012

Red pepper (Capsicum annuum L.) powder is widely used as a spice and flavor ingredient in the food industry. It is well known that during the drying process red pepper undergoes physico-chemical and nutritional changes. The objective of this study was to investigate the quality of red pepper powder according to drying method. Red pepper was dried by far-infrared drying, hot air drying, and polyethylene (PE) house drying. Average moisture content of dried red pepper powder from the three different drying methods was $12.5{\pm}0.3%$. The pH level slightly increased from 4.93 before drying to 5.00~5.54 after drying. Contents of capsaicinoids were highest (224.40 mg/100 g) in the PE house drying method and lowest (191.87 mg/100 g) in the hot air drying ($70^{\circ}C$) method. However, capsaicinoid contents were not significantly different among the various drying methods. Vitamin C content decreased as temperature increased. Drying conditions, particularly temperature, lead to loss of vitamin C in red pepper, resulting in quality degradation. Taken together, these results demonstrate that the content of vitamin C, one of the major factors affecting pepper powder quality, was affected by drying temperature.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.266-278
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• 2012

The objective of this study was developing dynamic stand growth model to predict diameter at breast height (DBH) growth by thinning intensity and cycle for major tree species of South Korea. The yield table, one of static stand growth models, constructed by Korea Forest Service was employed to prepare dynamic stand growth models for 8 tree species. In the process of model development, the thinning type was designated to thinning from below and equations for predicting the DBH change after thinning by different intensities was generated. In addition, stand density (N/ha), age and site index were adopted as explanatory variables for DBH prediction model. Thereafter, using the model, DBH growth under various silvicuture through integrating such equations considering thinning intensities, and cycles. The dynamic stand growth model of DBH developed in this study can provide understanding of effectiveness in forest growth and growing stock when thinning practice is performed in forest. Furthermore, results of this study is also applicable to quantitatively assess the carbon storage sequestration capability.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.317-323
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• 2012

This study was performed in order to explore the growth characteristics by growing stage in the containerized seedling and the bare root seedling of Chamaecyparis obtusa Sieb. et Zucc., which is the major plantation species of Korean southland. The height growth of 1-year-old bare root seedlings was better than containerized seedlings, which grew in the containers with capacity of 31.2 mL and 300 mL. The root collar diameter growth was the best in the containerized seedlings of container with 300 mL. The 2-year-old bare root seedlings were surveyed to be better in the height and root collar diameter growth than the containerized seedlings of container with 300 mL. In the comparison of dry mass production, it was the highest in 32 mL containerized seedlings as for 1-year-old above ground and in 300 mL containerized seedlings as for below-ground and total dry mass production. In case of 2-year-old seedlings, it was indicated to be high in bare root seedling as for the part above ground and in dry mass production of the containerized seedling as for the part below ground. In the comparison on root morphological traits of seedlings such as the total root length, the root project area, the root surface area, the average diameter in root, and the root volume, all of 1 and 2-year -old containerized seedlings showed the higher growth than the bare root seedlings except the average diameter in root. Synthesizing the results of this experiment, the containerized seedlings are relatively excellent in root development compared to bare root seedlings in the process of producing seedlings of C. obtusa, thereby being judged to have grown into excellent seedlings.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.407-414
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• 2013

This study was conducted to classify forest cover types using the multivariate statistical analysis in the natural forest of western Mt. Jiri. On the basis of the vegetation data by point quarter sampling, the adopted analytical methods were species-area curve (SAC), hierarchical cluster analysis (HCA), indicator species analysis (ISA), and multiple discriminant analysis (MDA). SAC selected the outlier tree species which was likely to have no influence on the classification of forest cover types, excluded from all analytical process. Based on forest vegetative information, HCA classified the study area into 2 to 10 clusters and ISA indicated that the optimal number of clusters were seven. MDA was taken to test the clusters that classified with HCA and ISA. The seven clusters were classified appropriately as overall classification success were 91.3%. The classified forest cover types were named by the ratio of the dominant species in the upper layer of each cluster. They were (1) Quercus mongolica Pure forest, (2) Mixed mesophytic forest, (3) Q. mongolica - Q. serrata forest, (4) Abies koreana - Q. mongolica forest, (5) Fraxinus mandshurica forest, (6) Q. serrata forest, and (7) Carpinus laxiflora forest.

• Journal of Korean Society of Forest Science
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• v.107 no.3
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• pp.316-323
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• 2018

This study was conducted with the intention of providing basic data that are essential for establishing compensation standards for forest products and diagnosing forestry management in the future by investigating the cultivation process of major wild edible greens such as Pteridium aquilinum var. latiusculum, Ligularia fischeri, and Allium victorialis and analyzing related incomes. According to the result, the cultivation was generally divided into the open filed cultivation and mountain cultivation by the cultivated item. The annual average income by unit area ($3.3m^2$) for each item was 6,500 won for Pteridium aquilinum var. latiusculum cultivated open filed, 3,200 won for Pteridium aquilinum var. latiusculum cultivated in the mountain, 20,400 won for Ligularia fischeri cultivated open filed, 20,900 won for Allium victorialis cultivated open filed, and 7,300 won for Allium victorialis cultivated in the mountain. Particularly, while consumer demand for Allium victorialis and Ligularia fischeri are increasing phenomenally recently, the annual average income per unit area ($3.3m^2$) for these wild edible greens grown open filed was distinctively higher than that for Pteridium aquilinum var. latiusculum. This can be explained by very high working expenses (land rent and labor cost) required for the cultivation of Pteridium aquilinum var. latiusculum compared with other items. As for Ligularia fischeri and Allium victorialis yielding high annual average income, the initial investment costs including the cost of purchasing seeds and seed stocks account for 40% of the working expenses or over and thereby requiring proper support from the government for solidifying the income source and promoting cultivation in the agricultural and mountain regions in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.985-991
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• 2008

This study was to investigated the changes of physiologically active components in germinated brown rice treated with chitosan (CGBR) and its anti-obesity effect in rat fed a high fat diet. Contents of physiologically active compounds such as total phenolic compounds, total dietary fiber, $\gamma$-aminobutyric acid (GABA), and total phytic acid in CGBR were significantly higher than those of traditional germinated brown rice (GBR). Lipase inhibitory activity of CGBR was higher than those of GBR and brown rice (BR). High fat diets containing CGBR, GBR, and BR were administered to three groups of male Sprague-Dawley rats for four weeks. All groups showed no significant difference in body weight, total abdominal fat, and plasma lipid levels. However, CGBR group appeared to have lower body weight gain and total abdominal fat level than other groups fed high fat diets containing GBR and BR. Total cholesterol and LDL-cholesterol contents in plasma of CGBR group were also lower than those of other groups. Thus, new germination method of brown rice using chitosan is a useful process, which utilizes plant defense responses to elevate the production of secondary metabolites and anti-obesity effect.

• Journal of the Korean Home Economics Association
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• v.17 no.4
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• pp.117-127
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• 1979

This study attempts to shed additional light on the national diffusion process and interaction of welfare services for children and mothers. The central hypothesis examined is the following : In general, the implant of social welfare system is first considered on the characteristics of their own socio-economics , and diffusion prodess of welfare services tends to occur faster in countries with open sicieties than in countries where entry barriers are high and society ranking rigid. The scope of the study is limited in several ways. Attention is concentrated on the agency of woman in the belief that an in-depth case study of one field can yield more insight than a less detailed investigation embracing a number of social welfare systems. The angency of woman is selected for several reasons. a) It is important the agency of woman alone produce more effective than services affecting both the child welfare and women's libertion bradually. Moreover, these services will form the heart of mother's welfare. b) The services of women's agency is gradually wide spread, since a role of government is still negligible before a full realization of economic income. c) The services of women agency is a prime example of a social welfare. d) statistical data and other information are more readily available. One of major findings of our study is the existence of the barriers inhibiting child welfare form " motherhood cult". Despite all the distinct advantages for mother and child , social attitudes appear to be some resistant on child welfare system among men and women even the agenices of women. What is surprised is the extent of the awareness that strategies of women's agency to liberate woman and to increate activities of women involve the strategies to liberate child. The conviction that solving application problems for child welfare in line with the activities of agency by women offer greater freedom and more advantage to mother are not apparent on the data collected from 18 of multi-functional agencies in our country. there are little sign that such agencies cooperate toward attainment of common goals. The intensive early focus of the movement on consciousness raising is a necessary beginning and such efforts by women's organizations would help both in the continuous evolution of women and child. Some of the agencies offer a variety of services to women and children, others are specialized in that they offer fewer services or even only one. Social welfare agenices giving service to children and their families are identified by various names usually women service and child welfare from govern , mental agency and voluntary public agency to foreign aided. What is totally missing , however, is an integrated synthesis of child welfare program Through women's agency. Social changes to occur, but delineation of appropriate and comprehensive social policy is also necessary at this point at this point since efforts, social changes and polices must be well coordianted and focused, as well as mutually supprotive and reinforcing.

• Journal of Korea Game Society
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• v.10 no.6
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• pp.115-124
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• 2010

In the beginning brain waves were used for monkeys to control robot arm with neural activity. In recent years there are research that measured brain waves are used for the control of programs which monitor the progression of dementia or enhance of attention in children diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). Moreover, low-price devices that can be used as a game control interface have become available. One of the problems associated with control using brain waves is that the mean amplitude, mean wavelength, and mean vibrational frequency of the brain waves differ from individual to individual. This paper attempts to propose a method to normalize measured brain waves using normal distribution and calculate the waveforms that can be used in controlling games. For this, a framework in which brain waves are converted in seven stages has been suggested. In addition, the estimation process in each stage has been described. In an experiment the waveforms of two subjects have been compared using the proposed method in the BCI English word learning program. The level of similarity between two subjects' waveforms has been compared with correlation coefficient. When the proposed method was applied, both meditation and concentration increased by 13% and 8%, respectively. Because the proposed regularization method is converted into a waveform fit for control functions by reducing personal characteristics reflected in the brain waves, it is fitting for application programs such as games.