• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.113-123
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• 1997

This study was initiated to build runoff plots, install soil and water quality monitoring systems and collect background data from the plots and neighboring soils as the 1st year study of a 5 year project to assess soil quality and develop the management practices for environmentally sound agriculture in mountainous soils. Eleven $3{\times}15m$ runoff plots and monitoring systems were installed at a field of National Alpine Agricultural Experiment Station to monitor soil quality and discharge of nonpoint source pollutants. Corn and potato were cultivated under different fertilizer, tillage and residue cover treatments. The soil has a single-layered cluster structure that has a relatively good hydrologic properties and can adsorb a large amount of nutrient. Concentrations of T-N, $NH_4$-N, and $NO_3$-N of surface soil sampled in the winter were relatively high. Runoff quality in the winter and thawing season in the spring was largely dependent on surface freezing, snow accumulation, temperature, surface thawing depth and so on. Runoff during the thawing season caused serious soil erosion but runoff quality during the winter was relatively good. Serious wind erosion from unprotected fields after the fall harvest were obserbed and best management practices to reduce the erosion need to be developed.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.5
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• pp.253-259
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• 2005

Magnetic encoder with relatively low pulse per rotation is generally used for detecting speed of the high-speed rotating machine. It is due to the fact of the mechanical problems of vibration and bearing stiffness and also the limit of maximum output pulse of the mounted encoder. The magnetic encoder is divided into two types, that is, toothed gear-wheel method and magnetic wheel method according to the shape of the rotation disk. In case of detecting speed by the tooth gear-wheel, the encoder itself can be acted as the additional inertia where the number of tooth determining the output pulse and the width of the wheel detecting the change of the magnetic flux density are relatively enough large considering the volume of the rotating machine. While the magnetic wheel method has the limit of the magnetizing number of the ring magnet, there is relatively few, if nv, the influence of inertia on the machine. In this paper, it is proposed a simple magnetic wheel encoder suited for the high speed rotating machine and the method of signal processing and the output characteristics are examined through the V/F operation of max 48,000(rpm) and 2.4(KW) spindle motor.

• Korean Journal of Human Ecology
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• v.9 no.2
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• pp.153-176
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• 2000

The purpose of this study is to compare the living cultures among three types of undergraduate students, grouped by commuting patterns, attending universities in Chung-Cheong Do: a long-distance type, a short-distance type, and a living-alone type. The survey was performed with questionnaires and the subjects were 1167 undergraduate students. The results are as follows: for a long-distance type, the levels of housing environments and consumption expenditures were relatively high, but the students felt constrainted by the commuting time. For a short-distance type, the consensus in decision-making with parents and the degree of conflict reconciliation were the lowest. For a living-alone type, the levels of housing environments and consumption expenditures were relatively poorer, but the students spent relative]y more time at school and the attitudes of school and department which they belong to were relatively higher.

• Environmental Analysis Health and Toxicology
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• v.14 no.3
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• pp.81-85
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• 1999

Diazinon, an organophosphate pesticide, is relatively highly toxic to fish and causes vertebral malformation and behavioral change of fish at relatively low concentrations. To elucidate biochemical mechanism of the behavioral change of Oryzias latipes (killifish) caused by diazinon, the effect of the insecticide on acetylcholine esterase activities and the levels of some neurotransmitters were evaluated. Acetylcholine esterase activities in both head and body were significantly lowered at the concentration of 10 ppb of diazinon and acetylcholine contents in head tended to be upregulated with increasing concentration of diazinon. Exposure of killifish to 5000 ppb diazinon resulted in gradual decrease in acetylcholine content in body part with exposure time. Norepinephrine and serotonin concentrations in killifish head and body were highest at 1000 ppb of diazinon while neurotransmitter were relatively low in fish unexposed or exposed to lower dose of the pesticide, suggesting that increased norepinephrine and serotonin can partially account for diazinon-induced behavioral abnormality.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.306-309
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• 2004

The susceptibility of landslides and the effect of landslide-related factors at Penang in Malaysia using the Geographic Information System (GIS) and remote sensing data have been evaluated. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from Landsat TM (Thermatic Mapper) satellite images; and the vegetation index value from SPOT HRV (High Resolution Visible) satellite images. Landslide hazardous areas were analysed and mapped using the landslide-occurrence factors employing the probability-frequency ratio method. To assess the effect of these factors, each factor was excluded from the analysis, and its effect verified using the landslide location data. As a result, land 'cover had relatively positive effects, and lithology had relatively negative effects on the landslide susceptibility maps in the study area. In addition, the landslide susceptibility maps using the all factors showed the relatively good results.

• Proceedings of the KSRS Conference
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• v.1
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• pp.495-498
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• 2006

Optical profile and spectral absorption of suspended solids in waters of Sanya bay was measured on August 8-14, 2003. Optical profile was taken by using MicroPro optical profile. Apparent optical indexes, vertical diffuse attenuation coefficient ($K_d$) and water leaving radiance (Lw), were calculated. $K_d$ at the blue end of the spectrum was greater than that at the red end of the spectrum in waters near Sanya River mouth, however, in waters near open sea, $K_d$ at the blue end of the spectrum was smaller than that at the red end of the spectrum. Distribution of water leaving radiance was relatively higher in waters near Sanya River mouth, but relatively weaker in near open sea water. Spectral absorption of suspended particulates was also measured. Results showed that the spectral absorption of chlorophyll a was greater in waters near Sanya river mouth, but relatively weaker in waters near open sea, which indicated higher concentration of phytoplankton in waters near Sanya river mouth. Except for water at the 5th sampling station, the ratio of spectral absorption of chlorophyll a to total suspended particulates in surface waters was greater than that in bottom waters at all stations.

• The korean journal of orthodontics
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• v.21 no.1 s.33
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• pp.171-183
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• 1991

This investigation was designed to categorize Angle's class II malocclusion groups through analyzing horizontal and vertical components of craniofacial skeleton in Angle's class II malocclusion. The material selected for this study consisted in standard lateral cephalogram of two hundred and twenteen children, eighty eight boys and one hundred twenty four girls, aged 6 through 18 years, having Angle's class II malocclusion. On the basis of findings of this study, the following results were obtained. 1. In horizontal skeletal classifications, 16 groups were classified according to FMN-A-B, SE-FMN-A, Ba-SE-Me, Ba-Se/Ra P. The sequences that have relatively high frequency are as follows: a) Horizontal Group 16 b) Horizontal Group 12 c) Horizontal Group 13 d) Horizontal Group 9 & 15 2. In vertical skeletal classification, 8 groups were classified according to the PMV/PP, PMV/Occ. P. PMV/Mn. P. The sequences that relatively high frequency are as follows; a) Vertical Group A b) Vertical Group D c) Vertical Group C d) Vertical Group H 3. In vertical and horizontal skeletal classifications, the sequence that relatively high frequency are as follows; a) Group13-A b) Group16-A & 9-A c) Group12-A & 15-A d) Group16-C

• Journal of Forest and Environmental Science
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• v.36 no.1
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• pp.55-61
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• 2020

In this study, basic data with respect to the introduction of Hipphophae rhamnoides L. and its cultivation in Korea could be obtained. According to the size of the plug cell tray, Chinese origin's rate of seed germination was relatively high in 128 plug cell tray, and growth was vibrant in 50 plug cell tray. The germination and growth of Russian origin seeds showed that they were relatively effective in 50 plug cell tray and with respect to soil environment, TKS-2 soil with untreated shading relatively promoted both germination and growth for Chinese origin, the rate of germination was high in bed soil for horticulture and growth result was good in TKS-2 in the case of Russian origin. It was confirmed that the germination rate of Chinese origin H. rahmnoides L. was highest in untreated shading and the shoot growth was vibrant in 70% shading while the growth in roots was vibrant in the untreated shading. In the Russian origin, H. rhamnoides L. the germination rate in 30% and 70% shading was about 50% which was higher than that in the untreated shading and general growth was vibrant in 30% shading.

• Journal of the Korean Ceramic Society
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• v.36 no.9
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• pp.954-964
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• 1999

The effect of fabrication variables and microstructures on the compressive strength of open cell alumina zirconia and silicon nitride ceramics fabricated by polymeric sponge method was investigated. Bulk density and compressive strength of open cell ceramics were mainly affected by coating characteristics of ceramic slurry on polymeric sponge that controlled a shape thickness and defect of the struts. Sintering temperature was optimized for enhancement of strut strength and compressive strength of open cell ceramics. Relative density and compressive strength behaviors were relatively well matched with the predicted values. Open cell ceramics of lower relative density below 0.1 prepared by first relatively well matched with the predicted values. Open cell ceramics of lower relative density below 0.1 prepared by first coating of ceramic slurry had thin triangular prismatic struts that were often broken or longitudinally cracked. With an application of second coating of slurry shape of struts was transformed into thickner cylindrical one and defects in struts were healed but the relative density increased over 0.2 Open cell zirconia had both the highest bulk density and compressive strength and alumina had the lowest compressive strength while silicon nitrides showed relatively high compressive strength and the lowest density. Based upon the analysis open cell silicon nitride was expected to be one of potential structural ceramics with light weight.

• Journal of the Korean Home Economics Association
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• v.28 no.3
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• pp.33-52
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• 1990

The aims of this study are to classify the life styles of urban housewives, to see their relationship between life style and demorgaphic variables, and also to see the relationship between life style and dietary patterns. This study has been performed by a questionsire about life style, demographic variables and dietary pattern. The selected samples were 475 housewives. The data were analyzed by factor analysis, cluster analysis, Duncan test, X-test and F-test. Life style is classified into 4 types: temporary enjoying type, passive irrational type, realistic conservative type, actual progressive type. The housewives who are in temporary enjoying type usually do randomly and don't think seriously something. And they have tendency to enjoy themselves. Therefore they don't have any plan for dietary behavior. The passive irrational type's housewives have no consistancy in their life and they do everything temporarily. The housewives who are in this type have relatively low incom, low level of education and they are high in age. The people who are in realistic conservative type act reasonably and elastically everything. They use convenient food very much, because they are willing to save time to make them. The housewives who are included in actual progressive type are well organized and planned in dietary behavior than others, when they dine out, they eat with family together in general, they usually use only a kind of western sauces and convenient food. They are relatively young, highly educated, and they are high income group. In conclusion realistic conservative type and actual progressive type are both relatively desirable type in dietary behavior, but in temporary enjoying type and passive irrational type, there, have to do some guide and education about managing family resources and dietary behavior.