• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.73-77
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• 2012

Co-(0.8 wt%) and Ce-(0.4 wt%) doped cubic zirconia ($ZrO_2$ : $Y_2O_3$ = 80 : 20, 70 : 30, 60 : 40, 50 : 50 wt%) single crystals grown by a skull melting method were heat-treated in $N_2$ at $1000^{\circ}C$ for 5 hrs. The orange, yellowish brown and brown colored as-grown single crystals were changed into either brownish red, yellow and green color after the heat treatment. Before and after the heat treatment, the YSZ (yttria-stabilized zirconia) single crystals were cut for wafer form (${\phi}6.5mm{\times}t2mm$). The optical and structural properties were examined by UV-VIS spectrophotometer and X-ray diffraction. Absorption by $Ce^{3+}(^2F_{5/2,7/2}(4f){\rightarrow}^2T_g(5d^1))$, $Co^{2+}(^4A_2(^4F){\rightarrow}^4T_1(^4F)$ or $^4T_1(^4P))$ and $Co^{3+}$, change of ionization energy and lattice parameter were confirmed.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.307-315
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• 2005

In this study we tried to develop a biological method for evaluating environment using the potter wasps as an indicator. Wasp species in family Eumenidae, were collected from 13 locations including agricultural area using nest trap. The wasps collected were classified and selected candidate species as an environmental evaluation indicator. Seven species were collected and the Anterhynchium flavomarginatum was the most dominant species. The number of the nest of potter wasps was 12.8/m both in the non-fertilizer and the non-pesticide areas and 7.2/m in the general agricultural areas. The number of nests was 13.4/m in the location where the Degree of Green Naturality (DGN) was high (4.28) and it was 1.2/m where the DGN was low (1.00), suggesting that the index of both richness and diversity tend to increase in locations with more nests. Based on these results, A. flavomarginatum, Orancistrocerus drewseni (Saussure), Isodontia nigellus and Chalicodoma sculpturalis were selected as indicator species for the evaluation of environment including agricultural ecosystem. And a standard for grading an environment (I to IV) was made based on the occurrence, the total number of nesting and the species diversity of potter wasps.

• Journal of the Korean Institute of Gas
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• v.21 no.6
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• pp.88-95
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• 2017

The usage of toxic gas in Korea is increasing in the development of high-tech industries such as semiconductors, displays and solar panels. The recent survey of domestic toxic gas consumption indicates an increase in annual average of 12.4 percent, but it is still focused on usage, and it is negligent in safety and treating the post. In September 2012, an accident occurred in Gu-mi involving hydrofluoric acid leak demonstrates the absence of safety management. Due to the incident, the government, industry and academia have been interested in chemical substances(toxic gas), and the government-led safety management has been established and implemented, but there are still a lot of safety blind spots. The purpose of this study is to develop effective measurement methods for the destruction or removal efficiency of gaseous materials emitted from the Scrubber used in the semiconductor and display industries. Also, this study demonstrated how toxic gas facilities can be applied without error by verification test for the measurement method guideline of the destruction or removal efficiency of the green-house gas reduction facility in the semiconductor and display industries used by the National Institute of Environmental Research and the UNFCCC, and suggested the differentiated measurement methods for toxic gas reduction facilities, and the third party certification for safety facilities is needed to prevent toxic gas accidents.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.790-797
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• 2011

Hydrodynamic similarity was analyzed by employing scaling factor in three phase fluidized beds. The scaling factor was defined based on the holdups of gas, liquid and solid particles and effectivity volumetric flux of fluids between the two kinds of fluidized beds with different column diameter. The column diameter of one was 0.102 m and that of the other was 0.152 m. Filtered compressed air, tap water and glass bead of which density was 2,500 kg/$m^3$ were used as gas, liquid and solid phases, respectively. The individual phase holdups in three phase fluidized beds were determined by means of static pressure drop method. Effects of gas and liquid velocities and particle size on the scaling factors based on the holdups of each phase and effective volumetric flux of fluids were examined. The deviation of gas holdup between the two kinds of three phase fluidized beds decreased with increasing gas or liquid velocity but increased with increasing fluidized particle size. The deviation of liquid holdup between the two fluidized beds decreased with increasing gas or liquid velocity or size of fluidized solid particles. The deviation of solid holdup between the two fluidized beds increased with increasing gas velocity or particle size, however, decreased with increasing liquid velocity. The deviation of effective volumetric flux of fluids between the two fluidized beds decreased with increasing gas velocity or particle size, but increased with increasing liquid velocity. The scaling factor, which was defined in this study, could be effectively used to analyze the hydrodynamic similarity in three phase fluidized processes.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.35-42
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• 2015

The purpose of this study is to offer the raw data for improving the method of landscape planting in apartment complex by objective surveying and analysing the growth ratio by type and ground planted in landscape tree. The results are as follows. In the survival ratio of tree, Pinus densiflora was the highest and Abies koreana was the lowest in evergreen tree. In case of deciduous tree, the species of the highest survival ratio were Diospyros kaki, Zelkova serrata, Prunus mume, Lagerstroemia indica and Ginkgo biloba. There showed that Sorbus commixta and Chaenomeles sinensis had the lowest survial ratio. In case of tree growth by types, Pinus strobus was the highest and Pinus densiflora var. globosa was the lowest among evergreen trees. Among deciduous trees, the growth ratio of Zelkova serrata was the highest, and the trees showed the lowest growth were Lagerstroemia indica, Magnolia denudata and Cornus officinalis. Pinus strobus, Cornus kousa, Ginkgo biloba, Chionanthus retusa and Acer palmatum were good growth in natural ground, and Zelkova serrata and Prunus armeniaca var. ansu were good in artificial ground. In the future, if you study the growth characteristics and shrubs that are excluded from the study of landscape trees in various locations are expected to derive objective data.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.405-411
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• 2015

Recently, according to the low-carbon green growth policy, the Stirling Engine has been increasing the interest of some sort of external combustion engines Stirling Engine is largely divided into three types ${\alpha}$, ${\beta}$ and ${\gamma}$. Among them, a ${\gamma}$-type engine is easy to design and can be applied variously. However, owing to the connection distance between the cylinder and the crank, there was a problem that ${\gamma}$-type occupies a larger volume than the ${\alpha}$ and ${\beta}$-types. As one of the methods to solve this problem, we have to consider about the Yoke crank which have been applied mainly to the ${\alpha}$-type. Because there are two advantages in not only reduction of engine volume but also parallelizing the cylinder. In this study, leading on from the existing design techniques for the Ross Yoke crank, this paper presents a simple method that can apply the yoke crank design of the ${\gamma}$-type stirling engine.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.530-536
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• 2006

Hardwood cutting propagation and early growth characteristics were investigated in order to develop the method of cutting propagation and to find out growth characteristics in the low altitude for in situ and ex situ conservation of Empetrum nigrum var. japonicum K. Koch, which is typical arctic alpine plants on Mt. Halla. The growth of roots and shoots was different depending on hormone concentrations or soil conditions. The survival rate, rooting rate, root growth, number of root and shoot growth increased with treatment of 100 mg/l or 500 mg/l NAA. Consequently, optimum condition of hardwood cutting was at treatment with 100 mg/l or 500 mg/l NAA. When plantlets from hardwood cuttings were exposed to the field condition, after 7 months survival rate was 73.3% without shading while $91.1{\sim}94.4%$ at shading conditions. In the green house, however, survival rate of plantlets were $95.6{\sim}97.8%$ without shading. The growth of plantlets was different depending on sites and shading conditions. Particularly, the best growth was obtained when the plantlets were grown in shading conditions. It indicates that relative humidity and light intensity are correlated with the growth in the low altitude area.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.1
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• pp.36-50
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• 1998

The purpose of this study was to investigate quantity food production practices in foodservices by analysing the menus of April, 1996, The questionnaire was developed and responded to by 96 dietitians in Sangju, Munkyung, Gumee, Kimchun, and Andong during November, 1996. The survey was performed by simple random samplings. The results were as follosw; 1. Hospitals and industry served food for thirty days and schools for twenty days. Kimchi was a select-menu for hospitals and one side dish for industry and schools. The type of menu was a single use menu which consisted of cooked rice, soups and three side dishes. 2. The most frequently used ingredients were green onions, rice, carrots, onions, Korean radish roots, pork, eggs, glutinous rice, and milk. Kimchis were served most frequently in all food services and cooked rices and soups were next. 3. The age of most of the respondents was 26 to 30.54.2% of subjects were juniou college graduates and 77.1% were single. Fifty seven point three percent of the dietitians lived with family relatives, or friends. 87.5% of the dietitians had been working for 1 to 5 years. 4. Most foodservices were self-operated. The number of meals served was determined by meal coupon counting in hospitals(37.5%), meal board counting in industry(29.2%), and attendance card counting in schools(41.1%) The cost of sales per meal was approximately 2,450 won in hospitals and was approximately 1,100 won in industry and schools. The average number of days per menucycle was 7.4 in hospitals. 10.3 in industry and 25.5 in schools. Hospitals, industry, and schools held about 118, 265 and 263 recipes respectively. The average number of dietitians was 2.6 in hospitals and 1.0 in industry and schools. Except for the number of recipes, the general practices of foodservices were significantly different(P<0.05). 5. In the general quantity food production, food and seasonings measuring was hardly done. the percentage of foodservices using chemical seasonings was higher in hospitals and industry than in schools. the most important concern was taste, Registered cooks were employed in 75% of schools but only 50.0% in hospitals and 20.8% in industry. Most of the dietitians respinded that their cooks skill was not bad. The education of unregistered cooks was performen once or two times a month in hospitals and industry, and in schools performed everyday. The problem when educating cooks was the lack of cooking skill of the dietitians in schools, and the lack of time in hospitals, and the negative attitude toward education in industry. The method for improving cooking in all foodservices was OJT, or the extension of education facilities and the development and dissemination of standard recipes. The frequency of throwing away leftovers was higher in hospitals. But in industry, the frequency of saving leftovers was higher. 6. Though all foodservices have standard recipes, the number that used them was low, Another problem is that standard recipes resulted in leftovers. The inconveniences of using standard recipes were the difficulty of applying standard recipes to various numbers of customers the complication of use, or facility insufficiency.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.289-303
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• 2007

This report includes basic data on nutrition education for Chinese adolescents living in Korea. A total of 183 Chinese adolescents living in Incheon participated in the survey. Body composition was analyzed by the Inbody 4.0., and questionnaires on personal dietary behavior were administrated. When compared with the body measure indices of Korean adolescents, we found that height was similar, but weight greater ($5{\sim}12 kg$) among the participants. Regarding obesity, 30.0% of all students were obese (BMI>25), especially the high school boys (42.0%). But in the case of middle school boys, the rates of obesity and under weight (BMI<18.5) were the same (both of them at 22.9%). The average WHR (Waist Hip Ratio) of the female high school group (0.9) was over the normal range. The average percent body fat for each group was also over the normal range. The percentage of students having breakfast everyday was 52.2%, and the rate of skipping breakfast was 25.0%. In the obesity group, the rate of skipping breakfast was remarkably high (P<0.05). Because lunch service was not available at the schools, a lunch box from home was the most popular pattern (43.1 %), but eating out was also popular at 36.6%. For the male high school students, the eating out rate was 62.8%. Since many have-lived in Korea for a few generations, the students' eating practices were much closer to the Korean pattern. For their ordinary meal pattern, 96.0% of the students included Korean foods. however, for New Years Day, the rate of having Gyo-Ja was 75.2%, and having Wol-Byung at Choo-seok was 78.6%, showing that the Chinese tradition still remains. In the case of food preferences, the percentage having Kimchi everyday was 62.1 %, but those drinking green tea was 13.1 %. For cold drinks, the rate for drinking them more than twice per week was 71.6%. The most preferred cooking method was frying with oil (50.6%). Among the students who had visited China (or Taiwan), the rate for 'bad food familiarity' was 37.0%, and the rate for 'did not know Chinese traditional course menus' was 71.3%. As a result of combining eating practices from both China and Korea, and the absence of lunch service in Chinese schools, students are showing bad dietary behaviors. therefore, it is necessary to provide proper nutrition education and a system for lunch service in Chinese schools.

• Korean Journal of Environment and Ecology
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• v.15 no.3
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• pp.267-275
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• 2001

This study was conducted to investigate the characteristics of bird community and to suggest a proper way how to manage and protect bird community in Mt. Paldal, Suwon City. The survey was carried out by line transect method from March 1992 to February 1993, and from October 1998 to August 1999. Twenty-seven birds were recorded, and these birds were also classified into 14 species for residents, 8 species fur summer visitors, 4 species for winter visitors and 1 species fur passage migrant in 1992. Twenty-one birds were recorded, and these birds were also belonged to 16 species fur residents, 2 species fur summer visitors, 2 species for winter visitors and 1 species for passage migrant in 1999. In 1992, seasonal change of number of species and individuals showed a typical pattern of temperate deciduous forests, however, seasonal pattern in 1999 was somewhat differed from that of temperate deciduous forest. According to data of migration habits of bird community in same months, percentage of residents were higher in 1999 and that of summer visitors were higher in 1992. In guild analysis of breeding bird community, bush-nesting and foraging guild that utilize the bush layer as nest and food resources showed the decreasing number of species and individuals, also summer visitors did the same decreasing trends from 1983. Therefore, it should be suggest that protection of bush layer for inhabitation of bush-nesting and foraging guild and summer visitors, and it will be considered that construction of green net-work among urban forests such as Mt. Kwanggyo, Mt. Chilbo, Mt. Paldal, Mt. Sukgi and Mt Yeogi in Suwon City.