• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.143-148
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• 2012

Sustainable agriculture requires reliable information on the spatial distribution of the soil chemical properties for effective management of paddy fields. In order to provide adequate soil nutritional information for environmental-friendly agriculture, we investigated the soil chemical properties for 260 paddy soils sampled in Gyeongnam Province from 1999 to 2011 by four years of interval. Soil chemical properties of pH, organic matter, available phosphate and silicate, exchangeable potassium, calcium, and magnesium contents were analyzed. The pH value, organic matter, available phosphate and silicate, and exchangeable calcium and magnesium in paddy soils were significantly elevated in 2011 compared to 1999. The excessive levels of organic matter and available phosphate in paddy soils were detected in 2011. The soil available phosphate was highest in mountain foot-slope (p<0.05) and the soil organic matter was highest in diluvial terrace (p<0.05). It revealed that the soil available phosphate was the responsible factor for the differentiation of soil chemical properties by the topography in paddy soils.

• Korean Journal of Psychosomatic Medicine
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• v.20 no.1
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• pp.32-39
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• 2012

Objective : Psychiatry in North Korea is believed to seem very different from psychiatry in South Korea. However, there is nearly no information regarding psychiatry in North Korea until now. Our study aimed to get information about North Korean psychiatry. Methods : Three North Korean defectors in South Korea, whose clinical experience as medical doctors in North Korea was over 10 years, were recruited. They underwent the semi-structured interview, content of which included the clinical experience with psychiatric patients, the details of psychiatry, the treatment of psychiatric patients, the stigma of mental illness, and the suicide, in North Korea. Results : In North Korea, psychiatric department was called as 49th(pronounced as Sahsip-gu-ho in Korean). Only patients with vivid psychotic symptoms came to psychiatric department. Non-psychotic depression or anxiety disorders usually were not dealt in psychiatry. The etiology of mental illness seemed to be confined to biological factors including genetic predisposition. Psychosocial or psychodynamic factors as etiology of mental illness appeared to be ignored. Psychiatry was apparently separated from political or ideological issues. The mainstay of psychiatric treatment is the inpatient admission and out-of-date therapy such as insulin coma therapy. Stigma over mental illness was common in North Korea. Suicide is considered as a betrayal to his/her nation, and has been reported to be very rare. Conclusion : The situation of psychiatry in North Korea is largely different from that of South Korea. Although some aspects of North Korean psychiatry are similar to psychiatry in former socialist countries, North Korean psychiatry is considered to have also its unique characteristics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.2
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• pp.239-247
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• 2015

This experiment was conducted to obtain the have higher contents of pharmaceutical constituents as well as higher yield from colchicine induced diploid and tetraploid extracts of Platycodon grandiflorum. In order to determine the biological activity, this study was focused to evaluate the cytotoxicity, antimicrobial on the bronthus disease bacteria, antioxidant enzyme activity of diploid and tetraploid extracts in P. grandiflorum. The activities of antioxidant enzyme according to different solvent extracts were measured as superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX). The cytotoxicity of methanol extracts of P. grandiflorum showed significant differences between tetraploid and diploid. That is, the cytotoxic effect against human cancer cell was higher in tetraploid than in diploid. At all extracts concentration, tetraploid samples showed high toxicity and the $IC_{50}$ (concentration causing 50% cell death) value showed the highest on HCT-116 cell ($105.91{\mu}g/mL$), and exhibited significant activity against the Hep 3B cell ($140.67{\mu}g/mL$), SNU-1066 cell ($154.01{\mu}g/mL$), Hela cell ($158.37{\mu}g/mL$), SNU-601 cell ($182.67{\mu}g/mL$), Calu-6 cell ($190.42{\mu}g/mL$), MCF-7 cell ($510.19{\mu}g/mL$). Antimicrobial activities of diploid P. grandiflorum were relatively low compared to tetraploid P. grandiflorum on most of the bacterial strains. In tetraploid P. grandiflorum, K. pneumoniae showed the clear zone formation (18~19 mm) of growth inhibition, followed by the clear zone formation of 13~15 mm on C. diphtheria and S. pyogenes. The antimicrobial activities in diploid P. grandiflorum were the highest on K. pneumonia (14~15 mm), and showed the clear zone formation of 11~12 mm on C. diphtheria and 12~13 mm on S. pyogenes. The antimicrobial activity is thought to look different depending on the bacterial strains and the polyploidy of P. grandiflorum. The root extract of P. grandiflorum had the highest (97.2%) SOD enzyme activity in ethyl acetate partition layer of tetraploid while water partition layer of diploid showed the lowest (48.6%) SOD enzyme activity. The activity of CAT showed higher values in the root of tetraploid than in the diploid of P. grandiflorum in all partition layers except butyl alcohol. The activities of APX and POD showed higher values in the root of tetraploid than in the diploid of P. grandiflorum in all fraction solvents except water layer. These results indicate that the tetraploid P. grandiflorum can be used as a source for developing cytotoxic agent and antimicrobials which can act against bronchus diseases bacterial strains.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.51-57
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• 2015

In this paper, in order to design the A / D converter with a high resolution of 14 bits or more for the biological signal processing, CMOS delta sigma modulator that is a 1.8V power supply voltage - were designed. we propose a new structure of The fourth order delta-sigma modulator that needs four op amps but we use only two op amps. By using a time -interleaving technique, we can re-construct the circuit and reuse the op amps. Also, we proposed a KT/C noise reduction circuit to reduce the thermal noise from a noisy resistor. We adjust the size of sampling capacitor between sampling time and integrating time, so we can reduce almost a half of KT/C noise. The measurement results of the chip is fabricated using a Magna 0.18um CMOS n-well1 poly 6 metal process. Power consumption is $828{\mu}W$ from a 1.8V supply voltage. The peak SNDR is measured as a 75.7dB and 81.3dB of DR at 1kHz input frequency and 256kHz sampling frequency. Measurement results show that KT/C noise reduction circuit enhance the 3dB of SNDR. FOM of the circuit is calculated to be 142dB and 41pJ / step.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.5
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• pp.23-29
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• 2015

In this study, human is the subject of driving a car, the actual EEG is a biological information in a number of reactions that are displayed while driving the vehicle by using a measuring device, occurs during travel of the road EEG to be collected, number of experiments the collected material on the basis of changes associated with running time, extracts the factors such as changes due to road geometry, and analysis was performed. The required changes in the EEG occurring during traveling experiment analysis alpha (${\alpha}$) waves, beta (${\beta}$) wave, after the primary extraction in the form of gamma (${\gamma}$) faction, the brain wave frequency of the entire period of the experiment change rate extracts, to calculate the change in frequency in response to EEG characteristics by applying the regression model to observe a learning effect in response to an increase in the number of experiments, as a result, depending on the number of experiments, EEG changes due to individual differences. The show, by repeatedly driving a section like this, it was possible to verify that comfortably travels driver accustomed in accordance with the stored road geometry and signal, safety facilities.

• Journal of Biomedical Engineering Research
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• v.22 no.5
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• pp.439-448
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• 2001

This paper considers the acoustical characteristics of the closing click sounds of the mechanical valves employed in an implantable biventricular assist device (BYAD) and their re1evance to the Physical states of the valved. Bj rk Shiley Convexo Concave tilting disk valve was chosen for the study and acoustic measurement was made for the BYAD operated in a mock circulatory system as well as implanted in an animal (sheep). In the BYAD operated in the mock circulatory system. three different states of the valve were examined, ie. normal. mechanically damaged. pseudo-thrombus attached. Microphone measurement for the BVAD implanted in the animal was carried out for five days at a regular time interval from one day after implantation. Characteristic spectrum of the sound from the valve was estimated using Multiple Signal Classification (MUSIC) in which the optimal order was determined according to Bayesian Information Criterion (BIC) . It was observed that the mechanical damage of the valve resulted in changes of the structure of the acoustic spectrum. In contrast. the thrombus formed on the valve did not change much the basic structure of the spectrum but brought about altering the spectral Peak frequencies and energies. Maximum spectral Peak (MSP) with the greatest energy was seen at 2 kHz for the normal valve and it was shifted to 3 kHz for the calve attaching the Pseudo-thrombus. Unlike the normal valve, strong spectral Peak appeared around 7 kHz in the sound from the valve mechanically damaged. In the case of the BYAD implanted in the animal. as the thrombus grew, acoustic energy was reduced relatively more in the low frequency components (〈 2 kHz) and the frequencies of the 1st, 2nd and 3rd MSP were increased little. The thrombus formation would result in reduction in both the variability of the 1st, 2nd and 3rd MSP and the value of the BIC optimal order.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.82-94
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• 2014

The purpose of this study is to investigate the cause of increasing dry zones through analyzing relationships between land cover and Vegetation Temperature Condition Index(VTCI) using Landsat 4-5 TM satellite images in Central Dry Zones of Myanmar. As a result of land cover classifications, while vegetation areas gradually decrease, residential area and cropland were increased. VTCI analysis shows that region (a) showed a gradual decrease in the area of severely arid, and increase in the area of moderate dry and wet, which sums up to a slight decrease in aridity. Region (b) also showed to increase in dry areas and severe aridity. The result of relational analysis between VTCI and land cover change showed high ratio of land cover change, from severe arid area to forest and residential farmland. The average VTCI decreased in the changed land covers, which indicates the relationship between aridity and land cover change and a gradual increase in the arid area was identified.

• Ecology and Resilient Infrastructure
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• v.3 no.3
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• pp.189-200
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• 2016

The species distribution model would be a useful tool for understanding how invasive alien species spread over the country and what environmental variables contribute to their distributions. This study is focused on the potential distribution of two invasive alien species, the common ragweed (Ambrosia artemisiifolia) and knotgrass (Paspalum distichum) in the Korean Peninsula. The maximum entropy (Maxent) model was used for the prediction of their distribution by inferring their climatic environmental requirements from localities where they are currently known to occur. We obtained their presence data from the Global Biodiversity Information Facility and the Korean plant species databases and bioclimatic data from the WorldClim dataset. As a results of the modelling, the potential distribution predicted by global occurrence data was more accurate than that by native occurrence data. The variables determining the common ragweed distribution were precipitation of the driest month and annual mean temperature. Both annual and the coldest quarter mean temperatures were critical factors in determining the knotgrass distribution. The Maxent model could be a useful tool for the prediction of alien species invasion and the management of their expansion.

• Journal of Korean society of Dental Hygiene
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• v.16 no.3
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• pp.471-477
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• 2016

Objectives: Fluoride is widely used in the prevention and control of dental caries. The purpose of this study is to examine the biological effects of Sodium fluoride on the proliferation of oral normal cell in vitro(MDPC-23, HaCaT, HGF-1 cells). Methods: The proliferation of normal cells and the cyto-skeletal change of normal cells were assessed by WST-1 assay and F-actin stain assay. The statistical significances of the resulting data were analyzed using SPSS(Window 12.0). Results: The sodium fluoride(0-12 mM) treatment decreased the cell viability in a dose and time dependent manner: HaCaT(6 h): $100{\pm}0$, $98{\pm}0.39$, $82{\pm}2.68$, $75{\pm}0.83$, $69{\pm}1$, $67{\pm}1.42%$(p<0.005); HaCaT(24 h): $100{\pm}0$, $98{\pm}1.85$, $54{\pm}0.64$, $43{\pm}0.4$, $38{\pm}0.32$, $36{\pm}0.13%$(p<0.006), MDPC-23(6 h): $100{\pm}0$, $93{\pm}1.48$, $85{\pm}0.28$, $82{\pm}1.58$, $79{\pm}1.48$, $76{\pm}1.93%$(p<0.009); MDPC-23(24 h): $100{\pm}0$, $91{\pm}1.26$, $58{\pm}0.65$, $49{\pm}1$, $44{\pm}0.74$, $2{\pm}0.05%$(p<0.005), HGF-1(6 h): $100{\pm}0$, $97{\pm}2.93$, $89{\pm}5$, $71{\pm}5.42$, $58{\pm}4.82$, $43{\pm}3.47%$(p<0.009); HGF-1(24 h): $100{\pm}0$, $97{\pm}2.05$, $73{\pm}1.73$, $22{\pm}1.61$, $14{\pm}1.73$, $7{\pm}0.85%$(p<0.005). Thus, changes in cell morphology and disruption of filamentous(F)-actin organization were observed in higher concentration. Conclusions: These results suggest that higher concentrations of fluoride lead to a reduce the number of cells and morphology change of normal cell.

• Journal of Biomedical Engineering Research
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• v.28 no.1
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• pp.46-54
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• 2007

Objective: The first aim of this study is to determine the effects of acupuncture on the autonomic nervous system (ANS) via Heart Rate (HR) and Pupil Size (PS), and to compare the effects of acupuncture on the subjects' ANS when they are in a sitting position with the effects when they are in a supine position. Methods: Ten healthy male subjects were randomized to receive either verum acupuncture stimulation in a sitting position (SitV), verum acupuncture stimulation in a supine position (SupV), sham acupuncture stimulation in a sitting position (SitS), and sham acupuncture stimulation in a supine position (SupS). Acupuncture stimulation was applied to Neguan point (PC6) on the forearm. The subject's electrocardiogram (ECG) and pupil size were recorded continuously from 5 min before stimulation to 12 min after stimulation. Results: Verum and sham acupuncture stimulation were found to have reduced heart rate (p<0.01) and to have increased pupil size (p<0.01) in all the subjects. But when the reduction in HR and the increment in PS after verum acupuncture stimulation (both sitting and supine position) were compared with those after sham acupuncture stimulation, it was found that the reduction in HR (74.48 and 73.47 bpm, p<0.063) and the increment of PS (7.32 and, 6.10 mm, p<0.001) after verum acupuncture stimulation were greater than those after sham acupuncture stimulation, and that the corresponding values were statistically significant. In addition, at the baseline, it was found that the subjects had a larger PS and a faster HR in a sitting position than when they did so in a supine position. And then the reduction and increment ratio in the subject's HR and PS when they underwent acupuncture stimulation in a sitting position was significantly different from the reduction and increment in their HR and PS when they underwent the procedure in a supine position-i.e., the reduction ratio in HR was greater when they underwent the procedure in a sitting position, and such reduction ratio was statistically significant (p<0.05). As for the increment in PS, it was greater when the subjects underwent the procedure in a supine position, and such increment was significant (p<0.05). Conclusion: Manual acupuncture stimulation on Neguan point (PC6) has more significant influence on the autonomic nervous system rather than sham acupuncture (tactile stimulation). And the position-induced different states of ANS have different influence on the acupuncture effect.