• 한국해양학회지
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• v.30 no.5
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• pp.371-381
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• 1995

To investigate the concentrations and transport patterns of particulate metals in river suspended matters, eighteen samples were collected from a fixed station located in the upper part of the Keum River through one year, and analysed for major elements (AI, Fe, P, Mn) and trace elements (Cr, Co, Ni, Cu, Zn, Cd, Pb, U). The contents of metals in suspended particulate matters (SPM) varied greatly with season and SPM load; maximum value in winter with low SPM level and minimum value in flood period and in spring Yangtze SPMs. The different trace metal level between rivers of Korea and China may be caused by the different geology of drainage basin(U) and by the different extent of anthropogenic input (Mn, Pb). Most of all particulate metals (>70%) except Mn, P and Cd were transported in the flood period with high water discharge and high suspended load. The magnitude of each transport phase (dissolved, non-detrital and detrital metals) was compared. The portions of labile metals (dissolved plus non-detrital metals) in the aquatic environment were in the range of 50%(Co) to 92%(Mn) of total metal transport and in the rank of Mn>Cd, U>Cu>Zn>Ni>Pb>Co.

• 한국해양학회지
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• v.2 no.1_2
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• pp.24-33
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• 1967

The variations of monthly mean sea levels along the coast of Korea anre studied graphic and harmonic methods with the data from 9 tides stations and compared with the variations of atmospheric pressure and the changes in density of sea water measured near some of the stations. The monthly mean sea level generally rises in Summer to Autumn, and falls in Winter to Spring and its range is from 20 cm to 50 cm. The variation of monthly mean sea level is of annual type, having one maximum and one minimum. The semi-range of annual components is 10.5 cm at Pusan and increases to the north in the west coast, to 20.8 cm at Inchon. It's phase is, on the whole, similar for the entire coast with about 210 (middle of August), except at Inchon, 200 . The variation of monthly mean sea level is mainly isostatic, or caused by those of sea water density and atmospheric pressure. Especially, the steric effect is predominant on the south- east coast around Pusan. However, in shallow long bays and estuaries on the west coast, the river runoff effect as well as local wind effect is also considerable. Magnitudes of annual variations at each stations are not constant, but widely variable from year to year. On the east and south coast, especially at Ulneungdo and Pusan the variations are large, which seem to be connected with the shifting of main current axes or current patterns in the offing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.1
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• pp.15-22
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• 2008

In this paper, we propose a numerical analysis on reversed current of distributed amplifier based on transmission line theory and proposed a theory to obtain optimum transmission line length to minimize the reversed currents by cancelling those components. The reversed current is analyzed as being simply absorbed into the terminal resistance in the conventional analysis. In the proposed analysis, however, they are designed to be cancelled by each other with opposite phase by the optimal length of the transmission lint Circuit simulation and implementation using pHEMT transistor were performed to validate the proposed theory with the cutoff frequency of 3.6 GHz. From the measurement, maximum gain of 14.5dB and minimum gain of 12.3dB were achieved In the operation band. Moreover, measured efficiency of the proposed distributed amplifier is 25.6% at 3 GHz, which is 7.6%, higher than the conventional distributed amplifier. Measured output power Is about 10.9dBm, achieving 1.7dB higher output power than the conventional one. Those improvement is thought to be based on the cancellation of refersed current.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4285-4289
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• 2015

Purpose: Blood hemoglobin levels are known to influence response to radiotherapy. This retrospective analysis compared the effect of hemoglobin levels upon response to radiation among patients treated with radiation alone (by accelerated hyperfractionated radiotherapy) versus those treated with concurrent cisplatin chemoradiotherapy. Materials and Methods: Among patients treated for locally advanced carcinoma of the cervix (LACC) during 2009-10, a total of 60 fulfilled the eligibility criteria. In this time frame, external beam radiotherapy was delivered with either concurrent chemoradiotherapy (CRT, n=31) (45Gy over 25 fractions, with weekly cisplatin at 40mg/m2), or with accelerated hyperfractionated radiotherapy (AHRT, n=29) (20Gy over 10 daily fractions over the first two weeks, followed by 30Gy over 20 fractions over the next two weeks, with two fractions of 1.5Gy per day, without the use of chemotherapy). Mean weekly hemoglobin (MWH) levels of all patients were calculated as the arithmetic means of weekly recorded blood hemoglobin levels. As per MWH, patients in both of the AHRT or the CRT groups were classified into two subgroups-those with MWH between 10-10.9g/dL, or with MWH>11g/dL. Complete response (CR) to external beam RT phase (prior to brachytherapy) was declared after clinical examinations and computed tomography. The CR rate was noted for both MWH sub-groups within each of the AHRT and CRT groups. Results: Within the AHRT group, patients with MWH>11g/dL had a much better CR rate in comparison to those with MWH:10-10.9g/dL (80% vs. 21.1%) which was statistically significant (p 0.0045). Within the CRT group, there was no significant difference in the outcomes within the MWH>11g/dL and MWH:10-10.9g/dL sub-groups (CR rates of 80% vs. 61.9%, p=0.4285). Conclusions: The importance of maintaining a minimum hemoglobin level of 11g/dL during RT is much greater for patients treated with RT alone, than for patients treated with concurrent chemoradiotherapy. Enhanced haemoglobin levels during RT may to an extent negate the ill-effects that may otherwise arise due to non-use of concurrent chemotherapy.

• Korean Journal of Human Ecology
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• v.11 no.3
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• pp.273-285
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• 2002

Three materials for sport underwear were manufactured by order for study, and among them, suitable material in order to perform an experiment on the effect of wearing was adopted. The results are as follows: The result of wearing an experimental clothes for sports manufactured as a foundation-type underwear for sports showed that if the same compositional materials were applied, laminating material had higher rate than that of others in the amount of sweat. Concerning relative humidity in clothes and the amount of sweat absorbed in clothes among the two kinds of materials which were produced by laminate, material 2(nylon+modal) was statistically exerts higher influence on the amount of sweat. The humidity in clothes keeps the optimal condition of 59.8%, and breast part showed the highest relative humidity. The material 2(nylon+modal) showed the highest comfortableness, the sense of warmth, humidity and voluminousness, and the sense of pressure. Follow-up survey revealed that in case of material 2, higher amount of sweat than that of the group objects in its early phase, and the amount of sweat varies from individuals. The temperature in clothes of folded parts of experimental clothes and maximum surface temperature was equivalent to that of average skin. With the lapse of time, the weight decreased of 11.03% in maximum, and 3.12% in minimum. The amount of change in the girth was greater in part of body frame than that of limbs, and especially, navel and waist part showed high decrease, and upper breast, breast and the largest part of abdomen showed relatively low decrease. The above experiment revealed that materials for suitable to the underwear for sports for loss of weight by an exercise should be made of doubled-nylon and modal, along with the laminate processing, which heightens the amount of sweat. Thus, wearing an experimental wear gave satisfaction in the view of the beauty of appearance as it did not discharge flowing secretion to the outside at the time of exercise.

• Journal of Navigation and Port Research
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• v.33 no.10
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• pp.691-697
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• 2009

Hardware dedicated off-the-shelf maritime differential GPS RSIM lacks the open architecture to meet all the minimum maritime user requirements and to include future GNSS improvements after recapitalization. This paper carries out a study to replace existing hardware dedicated differential GPS RSIM with software differential GPS RSIM in order to make up the weak point of hardware dedicated off-the-shelf maritime differential GPS RSIM. In this paper, the architecture of software RSIM is proposed for maritime DGPS recapitalization. And the feasibility analysis of the proposed software differential GPS RSIM is performed as the first phase to realize the proposed architecture. For the feasibility analysis, the prototype RF module and DSP module are implemented with properties as wide RF bandwidth, high sampling frequency, and high speed transmission interface. This paper shows that the proposed architecture has the possibility of real time operation of software RSIM functionality onto the PC-based platform through the analysis of computation time. Finally, this paper verifies that the L1/L2 dual frequency software differential RSIM designed according to the proposed method satisfies the performance specifications set out in RTCM paper 221-2006-SC104-STD.

• Korean Journal of Materials Research
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• v.23 no.3
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• pp.155-160
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• 2013

ZnO thin films co-doped with Mg and Ga (MxGyZzO, x + y + z = 1, x = 0.05, y = 0.02 and z = 0.93) were prepared on glass substrates by RF magnetron sputtering with different sputtering powers ranging from 100W to 200W at a substrate temperature of $350^{\circ}C$. The effects of the sputtering power on the structural, morphological, electrical, and optical properties of MGZO thin films were investigated. The X-ray diffraction patterns showed that all the MGZO thin films were grown as a hexagonal wurtzite phase with the preferred orientation on the c-axis without secondary phases such as MgO, $Ga_2O_3$, or $ZnGa_2O_4$. The intensity of the diffraction peak from the (0002) plane of the MGZO thin films was enhanced as the sputtering power increased. The (0002) peak positions of the MGZO thin films was shifted toward, a high diffraction angle as the sputtering power increased. Cross-sectional field emission scanning electron microscopy images of the MGZO thin films showed that all of these films had a columnar structure and their thickness increased with an increase in the sputtering power. MGZO thin film deposited at the sputtering power of 200W showed the best electrical characteristics in terms of the carrier concentration ($4.71{\times}10^{20}cm^{-3}$), charge carrier mobility ($10.2cm^2V^{-1}s^{-1}$) and a minimum resistivity ($1.3{\times}10^{-3}{\Omega}cm$). A UV-visible spectroscopy assessment showed that the MGZO thin films had high transmittance of more than 80 % in the visible region and that the absorption edges of MGZO thin films were very sharp and shifted toward the higher wavelength side, from 270 nm to 340 nm, with an increase in the sputtering power. The band-gap energy of MGZO thin films was widened from 3.74 eV to 3.92 eV with the change in the sputtering power.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1014-1019
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• 1994

To develope natural food preservatives, ethanol extract was preapred from the leaf mustard (Brassica juncea Coss) and antimicrobial activities were examined against 12 microorganisms which were food borne pathogens and/or food poisioning microorgaism and food-related bacteria and yeasts. The most active animicrobial concentration of the ethanol extract for most Gram positive microorganisms, Gram negative microorganisms, and lactic bacteria and yeasts was found to be 10, 20 and 40 mg/ml, respectively. when tested by a dose-response manner. Growth of Escherichia coli and STaphylococcus aureus were completely inhibited 4 hours after the addition of more than 20mg/ml of ethanole ethanol extract to the logarithic phase. Scanning electron icrographs of E. coli and Staph, aureus treated with ethanol extrract exhibited morphological changes, including the irregularly contracted cell surface of E. coli and expanded ellipsoidal shape of the Staph. aureus.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.587-590
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• 2013

Solid-liquid equilibria for mixtures composed of n-vinyl-2-pyrrolidone (NVP) and 2-pyrrolidone were measured as a basic study for the melt crystallization process to remove 2-pyrrolidone as impurity included in NVP. A differential scanning calorimeter (DSC) and a crystallizer were used and the experimental results obtained from two methods were similar. The mixture showed a eutectic system which has a single composition at the minimum melting temperature. Calculation results from simple thermodynamic equations were found in general agreements with present data. To determine the growth rate of NVP crystal which is important for the design of crystallization process, thicknesses of the crystal were measured with the time using a layer melt crystallizer. The growth rates increased as cooling temperatures decreased. Heat transfer coefficient correlated from present data was found to successfully describe the crystal growth behavior.

• Journal of Korea Water Resources Association
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• v.47 no.11
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• pp.1039-1050
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• 2014

The goal of this study is to demonstrate the diversity of model performance for various climatic elements and indicators. We evaluated the skills of the most advanced 17 General Circulation Models (GCMs) i.e., CMIP5 (Climate Model Inter-comparison project, phase 5) climate models in reproducing retrospective climatology from 1950 to 2000 over the Southeast US for the key climatic elements important in the hydrological and agricultural perspectives (i.e., precipitation, maximum and minimum temperature, and wind speed). The biases of raw CMIP5 GCMs were estimated for 16 different climatic indicators that imply mean climatology, temporal variability, extreme frequency, etc. using a grid-based observational dataset as reference. Based on the error (RMSE) and correlation (R) of GCM outputs, the error-based GCM ranks were assigned on average over the indicators. Overall, the GCMs showed much better accuracy in representing mean climatology of temperature comparing to other elements whereas few GCM showed acceptable skills for precipitation. It was also found that the model skills and ranks would be substantially different by the climatic elements, error statistics applied for evaluation, and indicators as well. This study presents significance of GCM uncertainty and the needs of considering rational strategies for climate model evaluation and selection.