• Geomechanics and Engineering
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• v.17 no.2
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• pp.165-173
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• 2019

Plate anchors are generally used for structures like transmission towers, mooring systems etc. where the uplift and lateral forces are expected to be predominant. The capacity of anchor plate can be increased by the use of geosynthetics without altering the size of plates. Numerical simulations have been carried out on three different sizes of square anchor plates. A single layer geosynthetic has been used as reinforcement in the analysis and placed at three different positions from the plate. The effects of various parameters like embedment ratio, position of reinforcement, width of reinforcement, frequency and loading amplitude on the pull out capacity have been presented in this study. The load-displacement behaviour of anchors for various embedment ratios with and without reinforcement has been also observed. The pull out load, corresponding to a displacement equal to each of the considered maximum amplitudes of a given frequency, has been expressed in terms of a dimensionless breakout factor. The pull out load for all anchors has been found to increase by more than 100% with embedment ratio varying from 1 to 6. Finally a semi empirical formulation for breakout factor for square anchors in reinforced soil has also been proposed by carrying out regression analysis on the data obtained from numerical simulations.

• Journal of the Korean Society of Safety
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• v.36 no.3
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• pp.66-73
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• 2021

This report documents the results of an at-power internal events Level 1 Probabilistic Safety Assessment (PSA) for a Korea research reactor (KRR). The aim of the study is to determine the accident sequences, construct an internal level 1 PSA model, and estimate the core damage frequency (CDF). The accident quantification is performed using the AIMS-PSA software version 1.2c along with a fault tree reliability evaluation expert (FTREX) quantification engine. The KRR PSA model is quantified using a cut-off value of 1.0E-15/yr to eliminate the non-effective minimal cut sets (MCSs). The final result indicates a point estimate of 4.55E-06/yr for the overall CDF attributable to internal initiating events in the core damage state for the KRR. Loss of Electric Power (LOEP) is the predominant contributor to the total CDF via a single initiating event (3.68E-6/yr), providing 80.9% of the CDF. The second largest contributor is the beam tube loss of coolant accident (LOCA), which accounts for 9.9% (4.49E-07/yr) of the CDF.

• Korean Journal of Biological Psychiatry
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• v.2 no.1
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• pp.115-122
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• 1995

This study was performed to know the relationship between neurologic soft signs (NSS) and clinical variables such as psychopathology. history of illness, and premorbid social adjustment in patients with schizophrenia. The authors evaluated NSS in 31 patients with schizophrenia using the structured tool for measuring neurologic abnormalities, Neurological Evaluation Scale- Korean Version(NES-K). Relationships between NSS and clinical variables such as duration of illness, intensity of precipitating stressors, duration of outpatient treatment, schooling, peer relationship, total duration of unemployment, total days of psychiatric admission, age, total days of being medicated, age at the first psychiatric admission, frequency of admissions, content of treatment, social adjustment, and severity of symptoms were analyzed. Differences between paranoid and non-paranoid schizophrenics were examined. In addition, Differences between patients with schizophrenia who have predominant positive symptoms and who have predominant negative symptoms were examined too. Total scores of NES-K were correlated with lower schooling (${\gamma}$=0.44, p<0.01). Scores of motor coordination subcategory were correlated with poor peer relationship(${\gamma}$=0.67, p<0.001). Other clinical variables were not correlated with any scores of NES-K. Paranoid and non-paranoid schizophrenics were not different in scores of NES-K. Also positive and negative schizophrenics were not different in scores of NES-K. Most clinical variables except schooling and peer relationship were not related with NSS. This results indicated that the meaning of these signs was not fully be understood. Introduction of the new classification concepts such as deficit or non-deficit syndrome will be helpful to elucidate the meaning of NSS in patients with schizophrenia.

• Journal of Environmental Science International
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• v.20 no.6
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• pp.737-753
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• 2011

The typical characteristics of seasonal winds were studied around the Pohang using two-stage (average linkage then k-means) clustering technique based on u- and v-component wind at 850 hpa from 2004 to 2006 (obtained the Pohang station) and a high-resolution (0.5 km grid for the finest domain) WRF-UCM model along with an up-to-date detailed land use data during the most predominant pattern in each season. The clustering analysis identified statistically distinct wind patterns (7, 4, 5, and 3 clusters) representing each spring, summer, fall, and winter. During the spring, the prevailed pattern (80 days) showed weak upper northwesterly flow and late sea-breeze. Especially at night, land-breeze developed along the shoreline was converged around Yeongil Bay. The representative pattern (92 days) in summer was weak upper southerly flow and intensified sea-breeze combined with sea surface wind. In addition, convergence zone between the large scale background flow and well-developed land-breeze was transported around inland (industrial and residential areas). The predominant wind distribution (94 days) in fall was similar to that of spring showing weak upper-level flow and distinct sea-land breeze circulation. On the other hand, the wind pattern (117 days) of high frequency in winter showed upper northwesterly and surface westerly flows, which was no change in daily wind direction.

• Economic and Environmental Geology
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• v.31 no.1
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• pp.53-57
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• 1998

Transient electromagnetic (TEM) method is also affected by cultural and natural electromagnetic (EM) noises, since it uses part of the broadband ($10^{-2}$ to $10^5Hz$) spectrum. Especially, predominant EM noise which affects a moving transmitter-receiver TEM system is sensor motion-induced noise. This noise is caused by the sensor motion in the earth magnetic field. The technique for reducing the sensor motion-induced EM noise presented in this paper is based on Halverson stacking. This Halverson stacking is generally used in a time-domain induced polarisation (IP) system to reject DC offset and linear drift. According to spectrum analysis of the vertical component of sensor motion-induced noise, the frequency range affected by the motion of an EM sensor is less than about 700 Hz in this study. With the decrease of the frequency, the spectral power caused by the motion of a sensor increases. For example, at the frequency of 200 Hz, the spectral power of the sensor motion-induced noise is $-90dBVrms^2$ while the spectral power of the EM noise measured with a fixed sensor on the ground is $-105dBVrms^2$, and at the frequency of 100 Hz, the spectral power of the sensor motion-induced noise is $-70dBVrms^2$ while the spectral power of the EM noise measured with a fixed sensor on the ground is $-105dBVrms^2$. With applying Halverson stacking to an artificial noise transient generated by adding a noise-free transient to sensor motion-induced noise measured without pulsing, it is shown that the filtered transient is nearly consistent with the noise-free transient within a delay time of $0.5{{\mu}sec}$. The inversion obtained from this filtered transient is in accord with the true model with an error of 5%.

• Ocean and Polar Research
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• v.36 no.2
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• pp.103-110
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• 2014

A wind-driven current in the East Sea from Lagrangian measurements of wind and current at 15 m using MiniMet drifters was analyzed. Spectral analysis of the current from 217 pieces of a 10 day-long time series shows the dominant energy at the inertial frequency for the current at 15 m. Wind has energy peaks at a 0.2-0.5 cycles per day (cpd) frequency band. The power spectrum of the clockwise rotating component is predominant for the current and was 1.5-2 times larger than the anticlockwise rotating component for wind. Co-spectra between the wind and current show two peak frequency bands at subinertial frequency and 0.5-0.3 cpd. Coherences between the wind and current at those peak frequencies are significant with 95% confidence and phase differences were $90-100^{\circ}$. From the phase differences, the efolding depth is estimated as 17 m and this e-folding depth is smaller than the estimation by Chereskin's (1999) 25 m using a moored Acoustic Doppler Current Profiler and an anemometer installed at the surface buoy. The angle between the wind-driven current (or ageostrophic current) and wind from this study was also much larger than the global estimate by Rio and Hernandez (2003) using reanalysis wind and drifters. The possible explanation for the discrepancy comes from the fact that the current is driven by a wind of smaller length scale than 250 km but the satellite or the reanalysis products do not resolve winds of length scale smaller than 250 km. Large rms differences between Mini-Met and QuickSCAT wind on spatial lags smaller than 175 km substantiate this explanation.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.61-67
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• 2018

High-frequency signals are analyzed at the inlet/outlet pipeline and pump casing during cavitation tests of the LOx pump for liquid rocket engines. Root-mean square values of all data are investigated with respect to cavitation number. The values of synchronous, harmonic, and cavitation instability frequencies are also calculated. Pressure pulsations of the inlet and outlet pipelines are affected by cavitation instabilities. The 3x component (i.e., the blade-passing frequency of the inducer) is predominant in the outlet pulsation sensor. This seems to be related to the fact that the number of impeller blades is a multiple of the number of the inducer blades. The cavitation instability is also measured at the accelerometer of the pump casing.

• The Journal of Korean Medicine
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• v.16 no.1 s.29
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• pp.184-197
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• 1995

After 45 patients examined as to the result of medical treatment among the ones who came to Dept. of Pain Clinic, Oriental Medical Hospital, Chunju Woosuk University complaining low back pain chiefly from Dec/19/1994 to Feb/7/1995 for 50 days or so were observed clinically, the results were obtained as follows: 1. In duration of the case history, acute stage(37.8%) was the most predominant, and subacute stage(35.6%) and chronic stage(26.7%) were revealed in turn. 2. In opinions of radiation, Spondylosis(26.7%) was the most predominant, Scoliosis(15.6%) and HIVD(11.1%) were revealed in order, and 3 cases were revealed to be negative. 3. In the radiating pain of the lower limb, the radiating pains of the left lower limb were the most predominant and those of the right lower limb and those of both lower limbs were revealed in turn. By the way, 31.1% of patients didn't suffer from the radiating pain of the lower limb. 4. In the grade of the seriousness of subsective symptom, Grade 2(66.7%) was the most predominant, and Grade 3, Grade 4, and Grade 1 followed it in order. 5. In the period of the treatments of medi-acupuncture, 2-5 day treatments(31.1%) were major and 6-10 day treatments(26.7%), 16-20 day treatments(11.1%), 26-30 day treatments(11.1%), over 31 day treatments(11.1%), 11-15 day treatments(4.4%), and 21-25 day treatments(4.4%) followed it by turns. Thus 2-10 day treatments are 57.8% and under 30 day treatments are 57.8% of all. 6. In the frequency of use of each medi-acupuncture, V was most frequency used in 41 cases(91.1%), and 11 cases of HN(24.4%), 8 cases of MOK(17.8%), 4 cases of OK(8.9%), 2 cases of B(4.4%), and a case of I(2.2%) were revealed in turn. 7. In the effect of treatments, 10 cases(22.2%) were excellent, 25 cases(55.6%) were good, 5 cases(11.1%) were fair, and 5 cases(11.1%) were poor. As the result, 88.9% of all changed for the better and all of these were improved within the third trial. 8. The effect of the treatments per durations was 100% in acute stage, 93.8% in subacute stage, and 66.7% in chronic stage. According to that, it was reavealed that the rate of treatments decreased as it came near to the chronic stage. 9. The effect of treatments per radiating pains was 87.5% in the radiating pains of the left lower limb, 81.8% in those of the right lower limb, 100% in those of both lower limbs, and 92.9% in case that patients have no radiating pains. So in the rate of treatments on radiating pains of the lower limbs, the case of both sides or no radiating pains was higher than that of one side. 10. In the effect of treatments per the condition of patients, Grade 4 showed 100% of improvement, Grade 3 showed 90.9% of improvement, Grade 2 showed 86.7% of improvement, and Grade 1 showed 100% of improvement. 11. In the effect of treatments per contents of treatments, the group treated with medi-acupuncture therapy, herb medication therapy, acupuncture therapy, and physiothrapy at the same time(Group 1) showed 100% of improvement, the group treated with medi-acupuncture therapy, acupuncture therapy, and physiotherapy simultaneously(Group 2) showed 73.7% of improvement, and the group treated with medi-acupuncture therapy and acupuncture therapy at the same time(Group 3) showed 100% of improvement. 12. 2-5 day treatments showed 78.6% of improvement, 6-10 day treatments showed 91.7% of improvement, and over 31 day treatments showed 100% of improvement. As the result, genarally the longer the period of treatment was, the better the effect of treatment was. 13. When only V was used, the rate of treatment was 96.2%. When only HN was used, the rate of treatment was 100%. When only MOK was used, the rate of treatment was 100%. When V and HN were used at the same time, the rate of treatment was 33.3%. When V and MOK were used at the same time, the rate of treatment was 100%. When V and OK were used at the same time, the rate of treatment was 100%. When V, HN, and MOK were used at the same time, the rate of treatment was 100%. When V, OK, and MOK were used at the same time, the rate of treatment was 100%. When V, MOK, and B were used at the same time, the rate of treatment was 100%. When V, HN, OK, and I were used at the same time, the rate of treatment was 100%. When V, HN, and B were used at the same time, the rate of treatment was 100%.

• The Korean Journal of Ecology
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• v.20 no.6
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• pp.405-411
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• 1997

Feeding behavior of the Russet Sparrow Passer rutilans was studied in two different types of habitats, shelter belts and isolated forests, in south-eastern Hokkaido, Japan, during the breeding seasons of 1995 and 1996. Predominant foods were determined as Caterpillar, Coleoptera, Diptera, Ephemeropera, Odonate and some other insects. The composition of the nestiling foods were not the same by season, region, and year. Larger foods in size were used by birds in isolated forests more frequently than in shelter belts. Amount of food per feeding was significantly larger in isolated forests than in shelter belts. Although food supply were more abundant in isolated forests than in shelter belts, the feeding frequency did not significantly differ between these two habitats. The nest density was higher in isolated forests than in shelter belts. Results of this study indicate that when the feeding condition is poor, birds tend not show specific food selection behavior, the feeding range is therefore larger, and the feeding interval is longer. Contrarily, the birds show a specific food selection behavior when they are in good feeding condition, the feeding range is therefor smaller and the feeding interval decreases.

• Journal of Chest Surgery
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• v.12 no.1
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• pp.1-8
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• 1979

Pulmonary aspergillosis is being recognized with increasing frequency in recent years and the-rising incidence of this infection parallels certain medical advances in antibiotics, chemotherapeutic and immunosuppressive therapy. The cavities of lungs resulting from tuberculosis, histoplasmosis or neoplasm are apt, to be infected by one of the species of the genus Aspergillus and eventually mycetomas are formed within the cavities. Authors have experienced 6 cases of pulmonary aspergillosis forming mycetoma in Dept. of Thoracic Surgery, Catholic Medical Center from Aug. 1976 to Feb. 1979. Hemoptysis or blood tinged sputum, the predominant symptom, occurred in all cases. All patients underwent pulmonary resection, 1 pneumonectomy, 3 lobectomies, 1 lobectomy with segmental resection and 1 segmental resection and survived well without death or complication. Primary aspergillosis was in 2 cases and underlying diseases were present in 4 cases: 3 pulmonary tuberculosis, 1 bronchiectasis. The common diagnostic study of intracavitary mycetoma was the posterioanterior chest roentgenogram; in cavities suspected of being diseased or in doubtful cases, tomography was most available to find fungus ball with air-meniscus shadow.