• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.2
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• pp.207-213
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• 2009

Electrolytic capacitors have been widely used in power electronics system because of the features of large capacitance, small size, high-voltage, and low-cost. Electrolytic capacitors, which is most of the time affected by aging effect, plays a very important role for the power electronics system quality and reliability. Therefore it is important to estimate the parameter of an electrolytic capacitor to predict the failure. This paper proposed a novel fault diagnosis method of an electrolytic capacitor used for voltage smoothing in boost DC converter. The equivalent series resistance(ESR) of electrolytic capacitor estimated from FFT result of filtered waveform of capacitor voltage/current. Main advantage of the proposed method include circuit simplicity and easy implementation. Simulation and experimental results are shown to verify the performance of the proposed method.

• Journal of the Korean Magnetic Resonance Society
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• v.4 no.2
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• pp.82-90
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• 2000

Photoinduced charge separation of alkylphenothiazines in molecular assemblies such as positively, negatively and neutrally charged micelle interface results in the paramagnetic phenothiazine cation radical. This was studied as a model system for the light energy conversion into chemical energy. The photoproduced phenothaizne cation radical was identified and its amount was quantized with electron spin resonance (ESR). The microenvironment of photoproduced cation radical was studied with pulsed-ESR. Such a charge separation is enhanced by the optimization of various structural factors of the molecular assemblies. The structural factors of molecular assemblies have focused on the interface charge, interface structure with different headgroups and interfacial perturbation by disolving interface active organic additives.

• The Journal of Internal Korean Medicine
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• v.20 no.1
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• pp.274-279
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• 1999

In order to look about the effect and possibility of oriental medical diagnosis and treatment of pancytopenia of myelodysplastic syndrome. For a patient who has pancytopenia. we diagnose him as myelodysplastic syndrome by CBC, LFT, Ultrasonic wave, Vitamin B12 test, Bone marrow test, Folic acid test and doing Herb-medication, Moxa-Tx continually, we observed the change of WBC, RBC. HGB. MCV, Platelet. ESR with following up CBC test ten times Finally, WBC increased by 900, RBC increased by 400000, MCV was reduced by 7fl. HGB increased by 1.3g/dl. Hct increased by 3.2%, ESR was reduced from 127 to 35mm/h. We diagnosed myelodysplastic syndrome as 'CONSUMPTIVE DISEASE' in oreintal medicine. The treatment effect of pancytopenia was achieved by Herb-medication and Moxa-Tx for invigorating qi, enriching the blood, invigorating the spleen and the kidney-yang, Now we need the study of oriental medical treatment for Aplastic Anemia and AML which is similar this.

• Journal of the Korean Chemical Society
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• v.46 no.2
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• pp.99-116
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• 2002

The thiazolylazo compounds and their Co(II), Ni(II) and Cu(II) complexes of barbituric acid, uracil, thiouracil, citrazinic acid, chromotropic acid, gallic acid, pyrogallol and salicylic acid were pre-pared and characterized by $^1H$ NMR , IR and the effect of pH on the electronic absorption spectra . The mode of ionization, the electronic transitions and the dissociation constants were discussed. The stoichiometries of the complexes were of 1:1, 2:1 and 3:2 (M:L). The copper complexes are of isotropic ESR spectra (except that of gallic acid which showed a complicated one) and are of magnetically diluted behaviour with orbital con-tribution. Detailed DTA data were obtained and discussed.

• Korean Journal of Food Science and Technology
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• v.44 no.6
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• pp.673-679
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• 2012

Ten commercially available red pepper powders were investigated using photostimulated-luminescence (PSL), thermoluminescence (TL) and electron spin resonance (ESR) analyses to confirm their irradiation status. The application of PSL, TL, and ESR analyses was also confirmed by in-house irradiation. In PSL-based screening, all samples gave negative photon counts (<700 PCs). The PSL calibration dose (1 kGy) showed a low sensitivity of 4 samples, while the others provided reliable screening results. TL glow curves demonstrated maximum peaks after $250^{\circ}C$ for the 6 samples; however 4 samples gave complex TL glow curves with maximum peaks in the range of $185-260^{\circ}C$ (radiation-specific), which could be the effect of an irradiated component in low concentration as the TL ratios of all samples were <0.1. Radiation-specific ESR features were absent in the all commercial samples. Variable irradiation detection properties were found; where the TL analysis showed the possible presence of an irradiated component in 4 samples requiring further monitoring and investigation.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.124-130
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• 2013

Of all the brominated flame retardants (BFRs), TBBPA has the largest production volume (50% of the BFRs in current use). It is interest to investigate how they may degrade, because of it can pose an environmental hazard. By using UV-A (${\lambda}=352nm$ ), we have found that the UV-A irradiation increased the photodecomposition reaction rate of TBBPA in an intensity-dependent manner. We also observed 2,6-dibromo-p-benzosemiquinone radical ($a_{2H}=2.36G$, g = 2.0056) generated from TBBPA by reaction with singlet oxygen ($^1O_2$). On the other hand, when an aqueous preparation of HA was irradiated in the presence of TBBPA, the typical spectrum of semiquinone radical was detected by electron spin resonance (ESR). And then, we have found that the photodecomposition rate of TBBPA is decreased in depend on HA concentration. Radical formation and the reactive rate of TBBPA were inhibited by sodium azide used as a singlet oxygen quencher. Therefore we report that a similar $^1O_2$-induced oxidation can be initiate in aqueous solutions of TBBPA dissolved in humic acid (HA) by the UV-A irradiation (${\lambda}=352nm$). From these results, we suggest that the reaction rate of HA with $^1O_2$ is faster than that of TBBPA with $^1O_2$.

• Korean Journal of Biological Psychiatry
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• v.14 no.4
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• pp.241-248
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• 2007

Objectives : Schizophrenia is equally distributed in both sexes. However, later-onset, milder psychopathology, and better outcome are associated with the females. This reason is thought to be partly due to the estrogen system. Recently, it was suggested that estrogen receptor 1(ESR1) gene polymorphisms might affect the expression of ESR1 and were associated with several psychiatric disorders. Thus, we investigated the association between two single nucleotide polymorphisms(SNPs) in the ESR1 gene and Korean schizophrenic patients in this study. Methods : Genotype, allele, and haplotype frequencies of the two SNPs(rs 2234693 and rs 2228480) were analyzed between 218 Korean controls and 158 Korean schizophrenic patients. Also, age of onset and negative symptom scale scores according to genotypes were analyzed in the patients with schizophrenia. Results : There was a significant difference in allele frequencies of rs 2234693 between the schizophrenic patients and the controls(p=0.03). Genotype distributions(p=0.03) and allele frequencies(p=0.01) of rs 2234693 were significantly different between the female schizophrenic patients and the female controls. The frequency of TC-CC genotypes compared with TT genotype in the female schizophrenic patients was significantly higher than that in the female controls(OR=2.36). The mean age of onset in the schizophrenic patients with TC-CC genotypes was significantly lower than that in the patients with TT genotype. The frequency of rs 2234693C- rs 2228480G haplotype in the female schizophrenic patients was relatively higher than that in the female controls. Conclusions : These results of our study support the possibility that the ESR1 gene polymorphisms might be involved in the susceptibility of females to schizophrenia and play a role in sex difference of schizophrenia.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.376-382
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• 2002

Purpose : To identify clinical and laboratory features of atypical Kawasaki disease(KD), and to develop criteria for early diagnosis of atypical KD patients. Methods : All patients with KD treated at our hospital from January 1998 to June 2000 were reviewed retrospectively. Results : Among a total of 167 patients, 28(16.8%) were atypical KD of which seven(25%) were infants. Among the five cardinal symptoms, oral mucosal change(96.4%) occurred most frequently, followed by conjuntivitis(57.1%) and rash(46.4%). Most notable laboratory findings were anemia, and increased erythrocyte sedementation rate(ESR) or C-reactive protein(CRP). Coronary artery abnormalities developed in seven(25.8%) atypical KD patients, compared with 14.4% in typical KD patients. We considered oral mucosal change as major criterion, and conjunctivitis, rash, hematocrit <35% and ESR >30 mm/hr or CRP >3.1 mg/dL as minor criteria. Proposed modification in diagnostic criteria for atypical KD include fever of ${\geq}5$ days＋major criterion＋${\geq}2$ minor criteria, or fever of ${\geq}5$ days＋4 minor criteria. Conclusion : The modified diagnostic criteria has yielded a sensitivity 89.3%. Our diagnostic criteria may be used for early diagnosis of atypical KD.

• Environmental Mutagens and Carcinogens
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• v.15 no.2
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• pp.140-147
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• 1995

For studying the effect of different dietary fats on carcinogenesis, fatty acid composition of membrane and lipid peroxidation were measured. Male Sprague-Dawley rats were fed on diet containing 15%(w/w) beef tallow or soybean oil. A single dose of 50 mg 2-AAF/kg B.W. was injected i.p. in each diet group 10 times. Rats were sacrifled after 1, 5, 10, and 15 weeks from the first injection. By 2-AAF injection, !ipid peroxidation increased slightly compared to control group. The rats fed on different fats had similar MDA production and those fed on soybean oil had slightly higher free radical concentration measured by ESR. In young rats, iipid peroxidation level was high and hydroxy radical production was higher in soybean oil group than in beef tallow group. With age, the lipid peroxidation values were decreased initially then increased. The fatty acid composition in microsomal membrane was reflected by dietary fatty acid composition. In soybean oil group, monoenoic acid was lower and polyunsaturated fatty acid was higher than beef tallow group. Linoleic acid contents showed the most discrepancy among groups. By 2-AAF treatment, iinoleic acid content and unsaturation index increased in soybean oil group. But in beef tallow group, there was no difference in fatty acid contents.

• The Journal of Korean Medicine
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• v.26 no.2 s.62
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• pp.231-240
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• 2005

Objectives: In order to investigate the efficacy and safety of the newly developed herbal medicine Jetongdan, a placebo­controlled, randomized clinical trial of patients with osteoarthritis of the knee was undertaken. Methods: Data were obtained from 80 patients with OA of the knee. After enrollment, they were asked to answer a disease-specific questionnaire (Western Ontario and McMaster Universities (WOMAC) OA index) and analyzed with the erythrocyte sedimentation rate (ESR) in order to evaluate the efficacy of Jetongdan, and analyzed for aspartate transaminase (AST) level, alanine transaminase (ALT) level, blood mea nitrogen (BUN) level, and creatinine (Cr) level in order to evaluate the safety of Jetongdan. Results: The liver function and renal function did not deteriorate after treatment with Jetongdan. Composite WOMAC score and physical function subscale was improved, but pain subscale, stiffness subscale, and ESR were not improved by. This was possibly because the baseline characteristics of the two groups were not homogenized after randomization. Conclusions: Jetongdan could be a promising treatment option for osteoarthritis of the knee. Further study in a larger population with appropriate severity grades is recommended.