• Journal of Astronomy and Space Sciences
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• v.23 no.2
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• pp.117-126
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• 2006

The Diurnal variation of galactic cosmic ray (GCR) flux intensity observed by the ground Neutron Monitor (NM) shows a sinusoidal pattern with the amplitude of $1{\sim}2%$ of daily mean. We carried out a statistical study on tendencies of the local times of GCR intensity daily maximum aad minimum. To test the influences of the solar activity and the location (cut-off rigidity) on the distribution in the local times of maximum and minimum GCR intensity, we have examined the data of 1996 (solar minimum) and 2000 (solar maximum) at the low-latitude Haleakala (latitude: 20.72 N, cut-off rigidity: 12.91 GeV) and the high-latitude Oulu (latitude: 65.05 N, cut-off rigidity: 0.81 GeV) NM stations. The most frequent local times of the GCR intensity daily maximum and minimum come later about $2{\sim}3$ hours in the solar activity maximum year 2000 than in the solar activity minimum you 1996. Oulu NM station whose cut-off rigidity is smaller has the most frequent local times of the GCR intensity maximum and minimum later by $2{\sim}3$ hours from those of Haleakala station. This feature is more evident at the solar maximum. The phase of the daily variation in GCR is dependent upon the interplanetary magnetic field varying with the solar activity and the cut-off rigidity varying with the geographic latitude.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.12-19
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• 1999

CERES-rice, a rice growth simulation model, was used in conjunction with daily weather data to figure out the spatial variation of the phenology and yields of paddy rice at 168 rice cultivation zone units(CZU) of Kyunggi Province in 1997. Two sets of cultivar specific coefficients, which represent early and mid-season maturing varieties, were derived from field experiments conducted at two crop experiment stations. The minimum data set to run the model for each CZU (daily maximum and minimum temperature, solar irradiance, and rainfall) was obtained by spatial averaging of existing 'Digital Map of Korean Climate'(Shin et al., 1999). Soil characteristics and management information at each CZU were available from the Rural Development Administration. According to a preliminary test using 5 to 9 years field data, trends of the phasic development(heading and physiological maturity), which were obtained from the model adjusted for these coefficients, were in good agreement with the observed data. However, the simulated inter-annual variation was somewhat greater than the reported variation. Rough rice yields of the early maturing cultivar calculated by the model were comparable with the reported data in terms of both absolute value and inter -annual variation. But those of the mid season cultivar showed overestimation. After running the simulation model runs with 1997 weather data for 168 CZU's, rough rice yields of the 168 CZU's calculated by the model were aggregated into corresponding 33 counties by acreage-weighting to facilitate direct comparison with the reported statistics from the Ministry of Agriculture and Forestry. The simulation results were good at 22 out of the 26 counties with reportedly increasing yield trend with respect to the past 9 years average.

• Journal of the Korean Geophysical Society
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• v.7 no.1
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• pp.11-21
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• 2004

The variation of geomagnetic field and absolute magnetic field at the geomagnetic observatory of King Sejong Station has been measured with 3-component ring core fluxgate magnetometer, proton magnetometer and D-I magnetometer. With data obtained from King Sejong Station during 2003, thediurnal and annual variations of geomagnetic field were researched and compared with those at other observatories. The deviation of daily variation of magnetic field in antarctica decreased gradually during winter season due to sun effect. The rates of componental annual variation of magnetic field at King Sejong Station were calculated using the least-square method under the assumption that the annual variation of magnetic field is linear. The rates are -55.93 nT/year in horizontal intensity, -0.87 min./year in declination, 58.30 nT/year in vertical intensity, and -69.85 nT/year in total intensity of magnetic field. A remarkable variation was caused by the magnetic storms occurred on 29~30 October, which were so powerful that the variation was observed in mid latitudes as well as high latitudes. The values of variation are generally 1500 2000 nT in Antarctica including King Sejong Station, 350 500 nT in East Asia. The measurement of absolute magnetic field shows that ring core fluxgate magnetometer has relatively large error range under cold temperature.

• ALGAE
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• v.20 no.2
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• pp.133-140
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• 2005

Daily variation of phytoplankton community and environmental parameters were investigated at the lower Nakdong River (Mulgum) from January 2002 to December 2003 to investigate the dynamics of a phytoplankton community in detail. The daily results of water quality in this investigation showed pH (8.1 $\pm$ 0.7), DO (10.3 $\pm$ 2.7 $mg{\cdot}l^{-1}$), water temp. (18.8 $\pm$ 7.4°C), BOD (2.4 $\pm$ 1.0 $mg{\cdot}l^{-1}$), COD (5.3 $\pm$ 1.2 $mg{\cdot}l^{-1}$) and chl. a (43.5 $\pm$ 35.1 mg ${\cdot}m^{-3}$). The results of nutrient factors were the following: TN (3.1 $\pm$ 0.8 $mg{\cdot}l^{-1}$), NO3-N (2.5 $\pm$ 0.5 $mg{\cdot}l^{-1}$), TP (90 $\pm$ 48 ${\mu}g\;{\cdot}\;l^{-1}$), PO4-P (43 $\pm$ 30 ${\mu}g\;{\cdot}\;l^{-1}$). Dominant phytoplankton species during the study period were diatom (Stephanodiscus hantzschii, Aulacoseira granulata var. angustissima and A. italica) and cyanobacteria (Microcystis aeruginosa, Aphanizomenon flos-aquae). The small centric diatom, Stephanodiscus hantzschii, was repeatedly dominant from late fall to the following spring (mean and maximum cell density, 2.3 × 103 $\pm$ 3.8 × 103, 4.5 × 105 cells $ml^{-1}$, respectively). Pinnate diatom, Aulacoseira granulata var. angustissima and A. italica, were frequently observed all season except January to March. Cyanobacteria, Microcystis aeruginosa and Aphanizomenon flos-aquae, proliferated in summer of 2002 except in 2003 due to heavy precipitation. The dominant zooplankton species (March-early May) was rotifer (Brachionus, Keratella, Polyarthra) and cladocerans (Diaphanosoma). The daily observed dynamics of the phytoplankton community in the lower Nakdong River in this study may play an important role in increasing the detailed resolution of limnological information and serving as ecological data for future studies.

• Health Policy and Management
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• v.9 no.2
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• pp.118-138
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• 1999

This study presents the variations on drug utilization for outpatients' URI, gastritis. and hypertension by the type of hospital- tertiary hospital. general hospital. hospital. clinic. It investigated drug expenses. daily drug expenses. days of medication. the highest price of the drugs used. and the number of the different drugs used for each disease and type of hospital. This study also performed analysis to see how much the variations of variables related to drug use affect the variations of drug expenses. The dependent variable was drug expenses and the independent variables were days of medication. the average price of the drugs used. and the number of the different drugs used. Analysis of the drug utilization was performed on NFMI(National Federation of Medical Insurance) 1994 medical expense claim data. Patients with secondary diseases were excluded. In this study. 379 patients with URI, 386 patients with gastritis. 1.257 patients with hypertension were included. It was founded that there were large variation on drug utilization between the types of hospital for same diseases. Days of medication were longest in tertiary hospitals and shortest in hospitals or clinics. Clinics showed the lowest daily drug expenses in all of the diseases investigated. Daily drug expenses were highest in general hospitals or hospitals. which also tended to use drugs of higher price than other types of hospital. General hospitals and hospitals had larger variations in daily drug expenses and the highest price of drugs. It suggested that drug might be utilized overly in general hospitals and hospitals and some other factors might influence on drug utilization in these hospitals. It was found that the variations of drug expenses were affected by the variations of drug price and days of medication rather than the number of the different drugs. Then the strategy to reduce the variations of drug utilization and to improve the quality of drug utilization should focus on the drug price and days of medication. Further study is needed to assess the quality as well as the variation of drug utilization and to show the factors which affect them.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.406-414
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• 2015

Existing relative researches for traffic were studied under favorable weather or excluding impact of weather. This study present traffic volume variation according to rainfall intensity in national highway provincial road and rainfall-factor. Continuous traffic count section match AWS after selecting to analyze provincial road 256 section. Weekdays ADT(Average Daily Traffic) and rainfall-factor are influenced by rainfall a little because of business travel. But non-weekdays ADT and rainfall-factor are influenced much more than weekdays because of leisure travel. Estimated AADT(Annual Average Daily Traffic) by adjusting rainfall-factor is lower MAPE than non-adjusting rainfall factor. So, rainfall have to be considered when estimating AADT. ADT decrease according to rainfall intensity, continuous studies considered rainfall intensity are needed when road design and operation.

• Physical Therapy Korea
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• v.10 no.2
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• pp.85-98
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• 2003

The purpose of this study was to investigate the changes of the activities of daily living (ADL) by the motor learning program for upper extremity in stroke patients. The subjects were sixty-two members who were treated at the department of occupational therapy. The ADL were measured with Functional Independence Measure (FIM). The result's were as fol1ows; 1. The ability to perform daily activities after treatment was significantly increased independent of age, gender, cause, affected side and speech disability (p<.01). The differences between the pre-treatment and the post-treatment was no significant correlation to sex, cause, affected side and duration of treatment, but the speech disability was significant. Therefore the pre-treatment scores and post-treatment scores were significantly different. 2. The variation of the pre-treatment and the post-treatment in the detail item to the performance of daily life of the stroke patients through the upper extremity motor learning program was significantly increased in self-care, sphincter control, locomotion, mobility, communication and social cognition (p<.01) Consequently, The motor learning program for upper extremity significantly improved the performance level of all ADL areas in stroke patients.

• Journal of Korean Society on Water Environment
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• v.29 no.1
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• pp.55-65
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• 2013

It is very difficult to apply stream flow data directly to the management of Total Maximum Daily Loads because there are some differences between the unit watershed and the stream flow monitoring network in their characteristics such as monitoring locations and its intervals. Flow duration curve can be developed by linking the daily flow data of stream monitoring network to 8 day interval flow data of the unit watershed. This study investigated the current operating conditions of the stream flow monitoring network and the flow relationships between the unit watershed and the stream flow monitoring network. Criteria such as missing and zero value data, and correlation coefficients were applied to select the stream flow reference sites. The reference sites were selected in 112 areas out of 142 unit watersheds in 4 river basins, where the stream flow observations were carried out in relatively normal operating conditions. These reference sites could be utilized in various ways such as flow variation analysis, flow duration curve development and so on for the management of Total Maximum Daily Loads.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.63-71
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• 2003

This study investigated about the seasonal variation of pollutant loads flowing into the Yeong-il bay from constructing Tank model which is the simulation model to evaluate the daily river discharge and pollutant load in the Hyeong-san river watershed. The estimated annual average river discharge of Hyeong-san river flowing into Yeong-il bay is about 878.34×10/sup 6/㎥/year which is about 73% of annual average of total precipitation in Hyeong-san river watershed. The annual average of pollutant load flowing into Yeong-il bay was estimated each 15.11 ton-COD/year, 23.24 ton-SS/year, 10.65 ton-TN/year, and 0.54 ton-Tp/year. For the seasonal variation of pollutant loads, it was tended as increasing of river discharge as increasing of inflow pollutant loads at June and July of summer and October of autumn. The main source of pollutant loads was found to be the Pohang city and Pohang industrial complex which are located near the mouth of Hyeong-san river. Therefore, for effective water quality management of Yeong-il bay, the counterplan to reduce pollutant loads from the main source of pollutant loads is required.

• Journal of Korean Society on Water Environment
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• v.24 no.3
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• pp.317-327
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• 2008

This study developed the methodology to calculate the total daily maximum load (TMDL) using the instreamflow requirement because the previous TMDLs were too simple to easily achieve. Instreamflow requirement which was the average low flow ($Q_{275}$) in the previous planning cannot consider the seasonal variation of streamflow. Therefore, this study used the instreamflow requirement which is a maximum value among hydrologic drought flow ($Q_{355}$), and environmental flows for ecology and scenery. The environmental flows for ecology were calculated using Physical HABitat SIMulation system (PHABSIM) which can estimate the necessary flow for fish survival by life cycle. Using the proposed method, all monthly TMDLs of streams in the Anyangcheon were calculated for the application.