• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.182-190
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• 2005

The fiber Raman amplifier(FRA) is a distinctly advantageous technology. Due to its wider, flexible gain bandwidth, and intrinsically lower noise characteristics, FRA has become an indispensable technology of today. Various FRA modeling methods, with different levels of convergence speed and accuracy, have been proposed in order to gain valuable insights for the FRA dynamics and optimum design before real implementation. Still, all these approaches share the common platform of coupled ordinary differential equations(ODE) for the Raman equation set that must be solved along the long length of fiber propagation axis. The ODE platform has classically set the bar for achievable convergence speed, resulting exhaustive calculation efforts. In this work, we propose an alternative, highly efficient framework for FRA analysis. In treating the Raman gain as the perturbation factor in an adiabatic process, we achieved implementation of the algorithm by deriving a recursive relation for the integrals of power inside fiber with the effective length and by constructing a matrix formalism for the solution of the given FRA problem. Finally, by adiabatically turning on the Raman process in the fiber as increasing the order of iterations, the FRA solution can be obtained along the iteration axis for the whole length of fiber rather than along the fiber propagation axis, enabling faster convergence speed, at the equivalent accuracy achievable with the methods based on coupled ODEs. Performance comparison in all co-, counter-, bi-directionally pumped multi-channel FRA shows more than 102 times faster with the convergence speed of the Average power method at the same level of accuracy(relative deviation < 0.03dB).

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.601-615
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• 2013

This study was conducted to compare the community structure and biodiversity of arthropods between conventional and organic red pepper fields. A total of 36 species of 24 families belonging to 10 orders from collected 28,718 arthropods; 6,901 individuals from conventional field and 21,871 individuals from organic field. A number of species comprising arthropod community was same in both fields as 32 species. Species richness of Diptera was the highest in conventional field and that of Hymenoptera and Colembolla was the highest in organic field. Abundance of Frankliniella intonsa was the highest regardless of farming method. Helicoverpa assulta was dominant in conventional field, and Homidia mediaseta, Diptera sp. 4 and Pardosa astrigera were dominant in organic field. Diversity of community on the ground was higher in organic field and statistically different. Similarity of arthropod community showed difference with 34.07% on the ground and 26.95% in the plant above ground. In the ecologically functional guild: species richness of general, pest and parasitoid of natural enemy groups in the plant above ground were statistically different and pest and parasitoid groups were higher in organic field, abundance of predator group of natural enemy on the ground was 2 times higher in organic field and statistically different and diversity of general and parasitoid groups in the plant above ground were statistically different. In the relative occupancy rate, pest group was the highest in conventional field and decomposer group was the highest in organic field. The results of present study is considered to provide useful information of arthropod community for developing efficient insect pest management in organic farming.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.111-124
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• 2010

To monitor the environment of land surface change is considered as an important research field since those parameters are related with land use, climate change, meteorological study, agriculture modulation, surface energy balance, and surface environment system. For the change detection, many different methods have been presented for distributing more detailed information with various tools from ground based measurement to satellite multi-spectral sensor. Recently, using high resolution satellite data is considered the most efficient way to monitor extensive land environmental system especially for higher spatial and temporal resolution. In this study, we use two different spatial resolution satellites; the one is SPOT/VEGETATION with 1 km spatial resolution to detect coarse resolution of the area change and determine objective threshold. The other is Landsat satellite having high resolution to figure out detailed land environmental change. According to their spatial resolution, they show different observation characteristics such as repeat cycle, and the global coverage. By correlating two kinds of satellites, we can detect land surface change from mid resolution to high resolution. The K-mean clustering algorithm is applied to detect changed area with two different temporal images. When using solar spectral band, there are complicate surface reflectance scattering characteristics which make surface change detection difficult. That effect would be leading serious problems when interpreting surface characteristics. For example, in spite of constant their own surface reflectance value, it could be changed according to solar, and sensor relative observation location. To reduce those affects, in this study, long-term Normalized Difference Vegetation Index (NDVI) with solar spectral channels performed for atmospheric and bi-directional correction from SPOT/VEGETATION data are utilized to offer objective threshold value for detecting land surface change, since that NDVI has less sensitivity for solar geometry than solar channel. The surface change detection based on long-term NDVI shows improved results than when only using Landsat.

• Journal of the Korean Society of School Health
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• v.2 no.1
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• pp.108-130
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• 1989

The purpose of this study is to provide the basic data for the development of school health nursing activities by surveying realities of school health nursing activities in schools lacking in a school nurse performed by teachers holding additional school health. The subjects for the study was selected from teachers holding additional school health who participated in the annual training course for teachers holding additional school health in 1988 organized by Province Education Council. 105 teachers holding additonal school health from Kyung-gi Province, 85 from Chung-buk province, 50 from Chun-buk Province, answered the questionaire. The results can be epitomized as follows. 1. General characteristics of Teachers Holding Additional School Health. The majority of the subjects are female (94.3%) and 64.1% of the subjects are in their twenties, 79.5% of them graduated from four-year teacher's college, 54.5% of them are unmarried, 74.5% has less than one-year experience as a teacher holding additional school health. 2. General characteristics of schools 92.4% of schools are national, of public schools, and 91.9% are located in country, elementary schools are 64%, junior high schools are 35.4%. The annual school nursing budget is unknow to 89.2% of them. The school nursing organization is non- existent to 85.6%. 82.4% of the school nursing clinics occupy their place solely, or jointly. 3. Status of School Health Nursing Activities In the questionaire, School Health Nursing Activities arc divided into Health Program planning and Evaluation (4 items), Clinic Management (4 items), Health Education (4 items), Management of School Environment 98 items), Operating of School Health Organization (1 item) and Health Care Service (25 items). The answers to each item measured by the Likert-type scale reveals that in the activities of techcrs holding additional school health the practice rate in Management of School Environment is 55%, 47% in Health Education, 45% in Health Program Planning and Evaluation, 32% in Health Care Service, 27% in Operating of School Health Organization, and 27% in Clinic Management. 4. The Relation between Influencing variables and School Health Nursing Activities. The results are as follows. (1) Health Program Planning and Evaluation: religion, marital status ($P<0.05^{**}$) (2) Clinic Management: age, school health organization ($P<0.05^{**}$) (3) Health Education: age ($P<0.01^*$), religion ($P<0.05^{**}$), business except for school nursing ($P<0.05^{**}$), form of operation ($P<0.05^{**}$), the number of clinic client a month ($P<0.05^{**}$). (4) Management of School Health Environment: age, marital status, business except for school nursing ($P<0.05^{**}$), presence of the annual school health nursing budget ($P<0.01^*$), school health organization ($P<0.05^{**}$). (5) Operating of School Health Organization: There is a statistical significance in Education, Interest in School Nursing ($P<0.05^{**}$). 5. The Regional Relationship of School Health Nursing Activity. There is a statistically significal difference in Health Education ($P<0.05^{**}$) and Health Care Service ($P<0.01^*$) of elementary school located in Kyung-gi, Chung-buk, Chun-buk Province. There is a statistically significant difference Health Program Planning and Evaluation of junior high Schools located in Kyung-gi, Chung-buk, Province ($P<0.05^{**}$). 6. The Correlation in School Health Nursing Activities. The analysis of the correlation in the 6 fields of school Health Nursng Activities shows that there is a statistically significant difference between Clinic Management and health Education, Clinic Management and Operating of School Health Organization, and between management of School Environment and operating of School Health Organization ($P<0.05^{**}$). The conclusions are as follows The 40.5 percent of schools should arrange nurse teachers by regulation 38, relative to the application of the Law of Education. But, in reality, teachers who have nothing to do with nursing, hold school health as an additional job. And it is very difficult to expect the qualititive health management of school faculty and students. In the 85.6 percent of schools, there is no organization for school health. And also, persons in charge of pracitcal affairs perform the school health activity without any knowledge about annual school health nursing budget. In the school health nursing activity of teacheres holding additional school health, operating of school, health organization and clinic management are the most difficult to get the cooperation from the persons relate to school and communities. There are a lot of problems in performing the school health nursing activity without any disposition of school health teachers, therefore, it is necessary to supplement school health teachers who had a professional training in order to make efficient the school health nursing management for children who are about to attend a school.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.1
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• pp.39-47
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• 2009

The importance of securing water resources and their efficient management has attracted more attention recently due to water deficit. In water budget analysis, however, evapotranspiration(${\lambda}E$) has been approximated as the residual in the water balance equation or estimated from empirical equations and assumptions. To minimize the uncertainties in these estimates, it is necessary to directly measure ${\lambda}E$. In this study, using the eddy covariance technique, we have measured ${\lambda}E$ in a mixed forest in the Seolmacheon catchment in Korea from September 2007 to December 2008. During the growing season(May-July), ${\lambda}E$ in this mixed forest averaged about $2.2\;mm\;d^{-1}$, whereas it was on average $0.5\;mm\;d^{-1}$ during the non-growing season in winter. The annual total ${\lambda}E$ in 2008 was $581\;mm\;y^{-1}$, which is about 1/3 of the annual precipitation of 1997 mm. Despite the differences in the amount and frequency of precipitation, the accumulated ${\lambda}E$ during the overlapping period(i.e., September to December) for 2007 and 2008 was both ${\sim}110$ mm, showing virtually no difference. The omega factor, which is a measure of decoupling between forest and the atmosphere, was on average 0.5, indicating that the contributions of equilibrium ${\lambda}E$ and imposed ${\lambda}E$ to the total ${\lambda}E$ were about the same. The results suggest that ${\lambda}E$ in this mixed forest was controlled by various factors such as net radiation, vapor pressure deficit, and canopy conductance. In this study, based on the direct measurements of ${\lambda}E$, we have quantified the relative contribution of ${\lambda}E$ in the water balance of a mixed forest in the Seolmacheon catchment. In combination with runoff data, the information on ${\lambda}E$ would greatly enhance the reliability of water budget analysis in this catchment.

• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.233-240
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• 2007

Extractions of Artemisia princeps Pampanini were obtained by using water and ethanol at different temperatures ($60^{\circ}C,\;100^{\circ}C$) with or without ultrasonification process (40 kHz). Yield of ultrasonificated extracts were about 20% higher than that of control group. Cytotoxicity of all conditions through adding 1.0 mg/$m{\ell}$ was below 37%, and treated with ultrasonification group was lower than the other group, about $5{\sim}8%$. $100^{\circ}C$ water extract with ultrasonification was higher anticancer activities as maximum 73% and higher selectivities at concentrations over 0.8 mg/$m{\ell}$. The extracts treated with ultrasonification were higher anticancer activities than the control. Densitometric analysis of bcl-2 revealed that extracts of high anticancer activity had low density. This results suggest that expression of bcl-2 protein by adding of Artemisia princeps Pampanini extracts relative to taking cancer. To conclude, optimum condition for efficient extraction of Artemisia princeps Pampanini is using water with ultrasonification at over $60^{\circ}C$ below $100^{\circ}C$.

• Journal of Korean Home Economics Education Association
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• v.23 no.3
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• pp.69-90
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• 2011

To develop the descriptive evaluation questionnaire with high validity and reliability on the Clothing and Textiles section of the middle school Technology & Hone Economics textbook, apply it to students and analyze its results. We made out a draft for descriptive evaluation questionnaire that was based upon the concrete establishment of the goal and the range of evaluation. We also made a rubric for scoring as well as sample answer-sheets. Finally, we completed a total of twenty three descriptive evaluation questions and we applied it to sixty five 2nd-grade students in two classes in a middle school. Descriptive evaluation questionnaire exhibited the relative high validity on each question. Moreover, three graders gave the same score on each question of descriptive evaluation, suggesting that descriptive evaluation questionnaire has the high inter-grader reliability and the strong correlation. But, low academic achievement was generally observed in the subjects. They had difficulty in describing their knowledge via their own language and drawing up accurate and detailed answers. They recognized the positive aspects of descriptive evaluation questionnaire, but they felt it uncomfortable due to study-burden and description itself. To overcome these limitations, it is required that students should experience various materials related to subject contents in classes as well as textbooks, concentrate themselves on finding solutions for problems, expand their scope, and practice describe them in advance. Therefore, the additional training for description evaluation questionnaire will be necessary for the more efficient and discriminative questionnaire. Also the questionnaire with high validity and reliability should be developed and the aggressive and voluntary participation of teachers will be needed.

• Water for future
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• v.28 no.6
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• pp.147-158
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• 1995

The purpose of this study is to establish a method of estimating the daily urban water demand using statistical model. This method will be used for the development of the efficient management and operation of the water supply facilities. The data used were the daily urban water use, the population, the year lapse and the weather conditions such as temperature, precipitation, relative humidity, etc. Kwangju city was selected for the case study area. The raw data used in this study were rearranged either by month or by season for the purpose of analysis, and the statistical analysis was applied to the data to obtain the regression model. As a result, the multiple linear regression model was developed to estimate the daily urban water use based on the seather condition. The regression constant and the model coefficients were determined for each month of a year. The accuracy of the model was within 3% of average error and within 10% of maximum error. The developed model was found to be useful to the practical operation and management of the water supply facilities.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.43-55
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• 1976

Fertilization and early development of turbo cornutus was studied based on the samples which were collected in Yeosu area. Particular emphasis was paid on induction of artificial spawing, fertilization rate, preembryonic development, the growth of the early larva and larval survival to various salinity. Among the various methods for induction of artificial spawning which have been tested for the present study, drying by exposure to air is the. most efficient, and percentage fertilization rate was $83.8-96.4\%$. The diameter of fertilized eggs was $0.182{\pm}0.0028mm$; and the diameter of egg membrane was $0.245{\pm}0.093mm$. Under the temperature range of $20.6-25.4^{\circ}C$ the larvae hatched out after 11:05-11:15 hours of fertilization. After 3.0-3.5 days of fertilization the planktonic larvae begand to settle, and the settlement terminated within 5 days. During the period of 150 days of early culturing the diameter growth of shell(M) and the diameter of shell aperture(A) was formulated as follows: $$1972\;M=0.33e^{0.02070D}$$ $$A=0.19e^{0.02282D}$$ $$1973\;M=0.32e^{0.02282D}$$ $$A=0.16e^{0.02596D}$$ During the same period of early culturing the relative growth of shell diameter and the diameter of shell aperture was formulated as follows : 1972 A=0.6478 S-0.1575 1973 A=0.5897 S-0.0515 After 11 days of larval hatching $0.02-0.18\%$ of planktonic larvae settled. After 150 days of settlement the survival rate of the early shells was $7.4-21.6\%$. Under the temperature range of $21.0-22.7^{\circ}C$ the optimum salinity range for the development of egg and the planktonic larvae was $30-35\%_{\circ}$.

• Journal of Korean Society on Water Environment
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• v.34 no.2
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• pp.183-201
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• 2018

The tolerance of Korean benthic macroinvertebrates to organic pollution has been analyzed since the early 1990s. However, considering the fact that there have been related studies carried out in some European countries since the early 20th century, the history of the research in Korea is very short and there is still much knowledge to supplement. We revised the saprobic valency, the saprobic value and the indicator weight value of 190 benthic macroinvertebrates taxa through the data of water quality and individual abundance collected from 7,086 sampling units in Korea from 2008 to 2014. The individual abundance of Uracanthella (Ephemeroptera) as a representative, one of the most common and abundant taxa in Korea, showed a typical lognormal distribution to 5-day biochemical oxygen demand (BOD5) concentration, and a normal distribution to the class interval of BOD5 concentration according to saprobic series. The value combining the mean individual abundance and the relative frequency of occurrence was a more efficient indicator value than that of each property alone. Benthic Macroinertebrates Index (BMI) was newly proposed as a modification of the saprobic index of Zelinka and Marvan (1961). BMI showed extremely significant correlation (determination coefficient $r^2$ > 0.6, n = 569 sites) with the concentration of BOD5, and the coefficient was a little higher than those of the previous indices. Until now, there has been very little research on the assessment of biological integrity of benthic macroinvertebrates community in Korea. While continuing researches into improve the reliability of BMI, it is necessary to develop multimetric indices for evaluating the integrity, including the composition of species and functional guilds, and the richness and diversity of the community.