Yong Ki Park

Dongguk University, Sŏul, Seoul, South Korea

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Publications (67)97.56 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The root bark of Morus alba L. (Mori Cortex Radicis; MCR) is traditionally used in Korean medicine for upper respiratory diseases. In this study, we investigated the antiasthmatic effect of kuwanon G isolated from MCR on ovalbumin (OVA)-induced allergic asthma in mice. Kuwanon G (1 and 10 mg/kg) was administered orally in mice once a day for 7 days during OVA airway challenge. We measured the levels of OVA-specific IgE and Th2 cytokines (IL-4, IL-5, and IL-13) in the sera or bronchoalveolar lavage (BAL) fluids and also counted the immune cells in BAL fluids. Histopathological changes in the lung tissues were analyzed. Kuwanon G significantly decreased the levels of OVA-specific IgE and IL-4, IL-5, and IL-13 in the sera and BAL fluids of asthma mice. Kuwanon G reduced the numbers of inflammatory cells in the BAL fluids of asthma mice. Furthermore, the pathological feature of lungs including infiltration of inflammatory cells, thickened epithelium of bronchioles, mucus, and collagen accumulation was inhibited by kuwanon G. These results indicate that kuwanon G prevents the pathological progression of allergic asthma through the inhibition of lung destruction by inflammation and immune stimulation. Copyright © 2014 John Wiley & Sons, Ltd.
    Phytotherapy Research 11/2014; 28(11). DOI:10.1002/ptr.5191 · 2.40 Impact Factor
  • Ji Min Jeon · Yong Ki Park · Mi Young Jeon
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    ABSTRACT: Drug-induced tubulointerstitial nephritis is one cause of acute kidney injury. Although traditional remedies have been widely used in South Korea, Dioscorea quinqueloba-induced tubulointerstitial nephritis has not been reported in the general population. A 72-year-old male patient was transferred to our hospital with pulmonary edema, oliguria, decreased mentality, severe generalized edema after taking D. quinqueloba 25 days ago. His initial lab findings showed a blood urea nitrogen level of 43.4 mg/dL, a creatinine level of 5.3 mg/dL. Urinalysis revealed SG (1.015), blood (many), protein (++) and WBC (0-3/HPF). Kidney biopsy demonstrated severe mononuclear cell infiltration into the renal interstitium with mild tubular atrophy. Aggressive renal replacement therapy and supportive care resulted in gradual restoration of his renal function. This case implies that D. quinqueloba may be one cause that induces tubulointerstitial nephritis in some patients.
    01/2014; 87(2):219. DOI:10.3904/kjm.2014.87.2.219
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    ABSTRACT: For the kinetic study of K2CO3/ZrO2 sorbent in the carbonation reaction to capture CO2 from the flue gas, reaction experiments were carried out at temperatures between 328 and 343 K for CO2 gas compositions not exceeding 18% at 1 bar, and a phenomenological kinetic model was proposed to fit the carbonation conversion data obtained. Time-dependent carbonation conversions of the sorbent appeared as sigmoid curves. Sigmoid characteristics of the conversion curve were more pronounced for the sorption reaction at lower temperature and lower gas phase concentration of CO2. Such conversion behavior of fresh-dried K2CO3/ZrO2 sorbent could be closely described with the reaction rate equation in the form: r = kf(X)yCO2n . The reaction rate constant k as a temperature dependent term could be represented by Arrhenius’ equation with the negative apparent activation energy of −17.43 kJ/mol and the pre-exponential factor of 3.83 × 10–3 1/min. The term f(X) was a function introduced to reflect the carbonation rate change with the fractional carbonation conversion X of the sorbent, and its parameters were determined by correlation equations of the reaction temperature and the gas phase concentration of CO2. The reaction order n with respect to yCO2, the gas phase mole fraction of CO2, was determined to be 0.49. And, the characteristics of K2CO3/ZrO2 sorbent in the carbonation reaction for CO2 capture was discussed in relation to the kinetics obtained.
    Industrial & Engineering Chemistry Research 06/2013; 52(26):9323–9329. DOI:10.1021/ie401407j · 2.24 Impact Factor
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    Bulletin- Korean Chemical Society 05/2013; 34(5). DOI:10.5012/bkcs.2013.34.5.1559 · 0.84 Impact Factor
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    ABSTRACT: Bupleuri Radix (BR) is a major component of several Oriental herbal medicines used to treat stress and mental illness. There are evidences that antidepressant drugs modulate oxidative damage implicated in the pathophysiology of neuropsychiatric disorder, including depression. The aim of the present study was to investigate antioxidant and proliferative effects of BR against oxidative stress induced by serum deprivation in SH-SY5Y cells. We examined the antioxidant effects of BR on a number of measures, including cell viability, formation of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and levels of both Bcl-2 and Bax. We also investigated the effects of BR on cell proliferation using the bromodeoxyuridine (BrdU) assay, and used Western blot analysis to measure changes in expression of the cell cycle phase regulators. 1) Serum deprivation significantly induced the loss of cell viability, the formation of ROS, the reduction of SOD activity, down-regulation of Bcl-2 expression and up-regulation of Bax expression. However, BR extract reversed these effects in dose-dependent manner. 2) Serum deprivation significantly reduced cell proliferation. Western blot analysis revealed that serum deprivation significantly decreased cyclinD1 and phosphorylated retinoblastoma (pRb) expression, and increased p27 expression. On the other hand, BR dose dependently reversed these effects. This study suggests that aqueous extract of BR may exert potent antioxidant effects and also play an important role in regulating cell cycle progression during neurogenesis. These effects of BR may be a potentially important mechanism of antidepressant underlying the observed antioxidant and proliferative effects.
    Psychiatry investigation 03/2013; 10(1):81-88. DOI:10.4306/pi.2013.10.1.81 · 1.15 Impact Factor
  • Ji Min Jeon · Yong Ki Park
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    ABSTRACT: Peritonitis is a major cause of morbidity in peritoneal dialysis patients; however, Aeromonas caviae rarely causes peritonitis in these patients. We report peritonitis due to A. caviae in a 72-year-old male with end-stage renal failure who had been undergoing automated peritoneal dialysis for 1 year. The white blood cell (WBC) count in the peritoneal fluid was 2,722/mm3 with 85% neutrophils. Gram staining of the peritoneal fluid yielded Gram-negative rods. Empirical antibiotic therapy with ceftriaxone was initiated intraperitoneally. However, drug sensitivity testing revealed that the organism was resistant. On the third hospital day, A. caviae was cultured from the peritoneal effluent, and the antibiotic regimen was switched to ciprofloxacin. The patient recovered rapidly and the WBC count of the peritoneal effluent decreased. He was discharged and the intraperitoneal ciprofloxacin therapy was continued for 14 days. The peritoneal catheter was not removed.
    01/2013; 84(3):438. DOI:10.3904/kjm.2013.84.3.438
  • Ji Min Jeon · Yong Ki Park · Mi Young Jeon
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    ABSTRACT: Drug-induced interstitial nephritis is one cause of acute kidney injury. Although traditional remedies have been widely used in South Korea, Corni fructus-induced interstitial nephritis has not been reported in the general population. A 65-year-old female patient was admitted with sudden onset of gross hematuria after ingesting Corni fructus tea for 2 weeks. Her initial lab findings showed a blood urea nitrogen level of 35.1 mg/dL, creatinine level of 1.7 mg/dL, albumin level of 4.5 g/dL, and hemoglobin level of 10.3 g/dL. Urinalysis revealed SG (1.025), blood (many), protein (+), and WBC (0-3/HPF). Her 24-hour total protein level was 1,120 mg/day. No specific abnormalities were found on serum and urine protein electrophoresis. Kidney biopsy demonstrated severe mononuclear cell infiltration into the renal interstitium with mild tubular atrophy and pericapsular fibrosis. Immediate withdrawal of Corni fructus, appropriate education, and conservative management resulted in gradual restoration of her renal function. This case implies that Corni fructus may be a causative allergen that induces acute interstitial nephritis in some patients.
    01/2013; 85(5):526. DOI:10.3904/kjm.2013.85.5.526
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    ABSTRACT: Study aims Some oriental herbal medicines have been used to treat neuropsychiatric disorders. We found previously that Kami-shoyo-san (KSS) possesses antidepressant-like effects at both the behavioral and molecular levels. Bupleuri Radix (BR), a major component of KSS, has affinity for both dopamine D2 and 5-HT1A receptors, which may be responsible for its antidepressant-like effects. In the present study, we investigated the antidepressant-like effects of BR in rats using the forced swimming test (FST) and the potential mechanisms of BR action in SH-SY5Y cells. Materials and methods The immobility time of rats treated with BR extract was measured in the FST. Western blotting was performed to examine the expression of proteins involved in the cAMP response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF)-mediated signaling pathway, thought to be a major target of antidepressant drug action. Results BR extract (900mg/kg) significantly reduced immobility time in the FST. Treatment with BR extract (10, 100 and 1000μg/mL) significantly increased CREB phosphorylation and elevated BDNF levels in SH-SY5Y cells. BR extract increased phosphorylation of Akt and glycogen synthase kinase-3β (GSK-3β). Moreover, BDNF small interfering RNA (siRNA) reduced elevated Akt and GSK-3β phosphorylation induced by BR extract. A phosphatidylinositol 3-kinase (PI3K) inhibitor blocked the BR-induced increase in phosphorylated Akt levels. Conclusions These findings suggest that an aqueous extract of BR can exert antidepressant-like effects in behavioral and molecular assays. These results demonstrate that BR may exert its effects through actions on CREB and BDNF activation, leading to stimulation of the PI3K/Akt/GSK-3β signaling pathway.
    European Journal of Integrative Medicine 08/2012; 4(4):e392-e399. DOI:10.1016/j.eujim.2012.07.979 · 0.65 Impact Factor
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    06/2012; 31(2):A62. DOI:10.1016/j.krcp.2012.04.505
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    ABSTRACT: The prevalence of malnutrition is high in patients on maintenance dialysis treatment in relation to low protein and energy intakes, metabolic disorders. We investigated the evolution of nutritional status during the first year after ABO incompatible living donor kidney transplantation (ABOI-LKT) in our hospital through assessment of chemical markers. A total of 16 kidney transplant recipients were followed during the first post-transplant year. Biochemical nutritional markers were assessed at 12 months later after ABOI-LKT. Differences in the means between the pre-transplant and post-transplant chemical markers were evaluated by paired Student’s t-test. Pre-transplantPost-transplantp valueBody weight (kg)57.74 ± 8.0054.43 ± 7.620.00S. hemoglobin (g/dL)10.44 ± 1.3212.04 ± 1.870.03S. BUN (mg/dL)46.55 ± 22.5218.13 ± 5.880.00S. creatinine (mg/dL)8.06 ± 3.391.15 ± 0.570.00S. calcium (mg/dL)8.70 ± 1.109.12 ± 0.720.04S. phosphate (mg/dL)5.20 ± 2.052.50 ± 1.050.00S. albumin (g/dL)3.59 ± 0.524.06 ± 0.330.00S. globulin (g/dL)2.83 ± 0.522.49 ± 0.350.00HDL (mg/dL)47.80 ± 12.3663.45 ± 16.970.00Total bilirubin (mg/dL)0.45 ± 0.130.78 ± 0.390.00AST (IU/L)14.20 ± 6.3020.90 ± 8.780.01ALT (IU/L)12.75 ± 5.6322.10 ± 12.530.01By the end of the first year, serum hemoglobin, calcium, albumin, HDL, bilirubin, AST, ALT were increased statistically. But serum phosphate, globulin were decreased statistically. In conclusion, successful ABO incompatible living donor kidney transplantation would restore a normal nutritional status even though the patients were performed plasmapheresis during the pre-transplant period.
    06/2012; 31(2):A62. DOI:10.1016/j.krcp.2012.04.506
  • Lin Huang · Chul Wee Lee · Yong Ki Park · Sang-Eon Park
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    ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
    ChemInform 12/2010; 30(49). DOI:10.1002/chin.199949099
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    ABSTRACT: Magnetocardiography (MCG) is a device to measure the weak magnetic fields generated from the heart using a superconducting quantum interference device sensor which converts magnetic flux to voltage and is the most sensitive sensor to detect magnetism. In the previous study, authors found that the values of MCG parameters of patients with non-ST-segment myocardial infarction were greater than those of age-matched controls (AMCs). In this study, we selected five different groups of patients considering their severity. We compared 10 MCG parameters recorded from 19 healthy young subjects (26.8plusmn13.4 years), 19 age-matched healthy subjects (55.4plusmn10.7), 23 stable angina patients (56.4plusmn7.6 years) with no stenosis (=0% on coronary angiogram) and normal echocardiogram, 24 unstable angina patients (61.9plusmn9.8 years) with severe stenosis (ges70%), and 20 Q-wave myocardial infarction (QMI) patients (57.3plusmn11.2 years) with severe stenosis (ges70%). To record the magnetic signals from a heart with minimal noise, a magnetically shielded room was used. The number of abnormal parameters was counted and magnetic field map (MFM) patterns were compared. As a result, young healthy subjects showed the smallest values in all 10 MCG parameters and QMI subjects showed the greatest values. Significant difference was found from dynamics parameters such as current angle, map angle, and distance dynamics between young healthy controls and AMC groups (p>0.05). No significant difference was found from AMC and stable angina groups even though parameter values of stable angina were slightly greater than those of AMC. Significant difference was found from five parameters between AMC and QMI subjects. These results are supportive to the previous analysis. In addition, the abnormal MCG parameters increased when the ischemic disease was worsened. Abnormal MFM patterns were easily found from QMI patients than stable angina pectoris. It is clear that abnormal MFM and parameters - - increase when the status of ischemic heart disease patients are getting worse.
    IEEE Transactions on Magnetics 07/2009; DOI:10.1109/TMAG.2009.2018878 · 1.21 Impact Factor
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    ABSTRACT: We present a computational study of reentry wave propagation using electrophysiological models of human cardiac cells and the associated magnetic field map of a human heart. We examined the details of magnetic field variation and related physiological parameters for reentry waves in two-dimensional (2-D) human atrial tissue and a three-dimensional (3-D) human ventricle model. A 3-D mesh system representing the human ventricle was reconstructed from the surface geometry of a human heart. We used existing human cardiac cell models to simulate action potential (AP) propagation in atrial tissue and 3-D ventricular geometry, and a finite element method and the Galerkin approximation to discretize the 3-D domain spatially. The reentry wave was generated using an S1-S2 protocol. The calculations of the magnetic field pattern assumed a horizontally layered conductor for reentry wave propagation in the 3-D ventricle. We also compared the AP and magnetocardiograph (MCG) magnitudes during reentry wave propagation to those during normal wave propagation. The temporal changes in the reentry wave motion and magnetic field map patterns were also analyzed using two well-known MCG parameters: the current dipole direction and strength. The current vector in a reentry wave forms a rotating spiral. We delineated the magnetic field using the changes in the vector angle during a reentry wave, demonstrating that the MCG pattern can be helpful for theoretical analysis of reentry waves.
    Progress in Biophysics and Molecular Biology 01/2008; 96(1-3):339-56. DOI:10.1016/j.pbiomolbio.2007.07.024 · 3.38 Impact Factor
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    ABSTRACT: Combined micro-Raman/UV-visible (vis)/fluorescence spectroscopy system, which can evaluate an integrated array of more than 10,000 microsamples with a minimuma size of 5 microm within a few hours, has been developed for the first time. The array of microsamples is positioned on a computer-controlled XY translation microstage with a spatial resolution of 1 mum so that the spectra can be mapped with micron precision. Micro-Raman spectrometers have a high spectral resolution of about 2 cm(-1) over the wave number range of 150-3900 cm(-1), while UV-vis and fluorescence spectrometers have high spectral resolutions of 0.4 and 0.1 nm over the wavelength range of 190-900 nm, respectively. In particular, the signal-to-noise ratio of the micro-Raman spectroscopy has been improved by using a holographic Raman grating and a liquid-nitrogen-cooled charge-coupled device detector. The performance of the combined spectroscopy system has been demonstrated by the high-throughput screening of a combinatorial ferroelectric (i.e., BaTi(x)Zr(1-x)O(3)) library. This system makes possible the structure analysis of various materials including ferroelectrics, catalysts, phosphors, polymers, alloys, and so on for the development of novel materials and the ultrasensitive detection of trace amounts of pharmaceuticals and diagnostic agents.
    Review of Scientific Instruments 08/2007; 78(7):072205. DOI:10.1063/1.2755745 · 1.58 Impact Factor
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    ABSTRACT: Bi-functional nanoparticles (NPs) that consist of silica-coated magnetic cores and luminescent lanthanide (Ln) ions anchored on the silica surface via organic linker molecules are reported. Compared to individual Ln ions, the hybrid NPs show a drastically enhanced photoluminescence due to the efficient ligand-to-metal energy transfer in the Ln-loaded NPs: the new bi-functional NPs could be used in a variety of biological applications involving magnetic separation and optical detection.
    Chemical Communications 05/2007; DOI:10.1039/b617608a · 6.83 Impact Factor
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    ABSTRACT: Magnetocardiography (MCG) has been introduced as an innovative non-invasive diagnostic tool to identify various heart diseases. However, there have been little data on the reliability of MCG parameters. The purpose of this study is to examine the test-retest reliability of different diagnostic parameters derived from MCG. We investigated short-, intermediate-, and long-term reliability of nine parameters from T (max/3)-T (max) interval, and five parameters from each time point such as QRS-wave, the peak of R-, and T-wave were evaluated. Short-term reliability was tested in the youngest 20 subjects (mean age = 26.3 +/- 4.9 years) in three sessions separated by 5 min. Intermediate-term reliability was tested in the 35 subjects with coronary artery disease (CAD) (65.1 +/- 7.1 years) with two recording sessions each in the morning and afternoon, separated by more than four hours. Long-term reliability was tested in seven subjects (37.1 +/- 8.8 years) using seven daily sessions. Interclass correlation coefficients (ICC) showed that test-retest reliability was good to excellent (0.99 > or = ICC > or = 0.80) for six out of nine parameters within T (max/3)-T (max). In addition, all parameters on the peak of R-wave, T-wave, and QRS-wave integrated were good to excellent (0.99 > or = ICC > or = 0.80) except for one parameter of CAD patients showing lower ICC values under 0.7. In conclusion, our study showed that the test-retest characteristics of the studied MCG parameters are generally stable and reliable over periods of minutes to days in subjects with different age spectrums.
    Annals of Biomedical Engineering 02/2007; 35(1):59-68. DOI:10.1007/s10439-006-9210-9 · 3.23 Impact Factor
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    ABSTRACT: Magnetocardiography (MCG) has been proposed as a noninvasive diagnostic tool to risk-stratify patients with myocardial infarction (MI) and ischemia. The purpose of this study is to find the MCG parameters that are sensitive enough to detect the non-ST-segment elevation myocardial infarction (NSTEMI) patients. MCG data were recorded and analyzed from 165 young controls (mean age = 27.2 +/- 9.0 years), 57 age-matched controls (mean age = 55.9 +/- 10.5 years) and 83 NSTEMI patients (mean age = 59.7 +/- 11.1 years). The MCG recordings were obtained using a 64-channel MCG system in a magnetically shielded room. Statistical analyses were performed for 24 parameters derived from QRS-, R-, T-wave, and ST-T period. Binary boundaries to detect NSTEMI patients out of control subjects were found using the receiver operating characteristic (ROC) curve for each parameter. Fifteen parameters showed a significant difference (P < 0.05 and P < 0.01) between NSTEMI and both of the control groups. For detection of NSTEMI, the angle of the maximum current and the filed map angle on T-wave peak showed the highest diagnostic performance from 75% to 92% including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value (area under ROC curve = 0.87 approximately 0.93). Our study showed that MCG has potential clinical application for detection of NSTEMI and should be further investigated.
    Annals of Medicine 01/2007; 39(8):617-27. DOI:10.1080/07853890701538040 · 4.73 Impact Factor
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    ABSTRACT: We have developed biocompatible ferrite (Fe3O4) nanoparticles whose surfaces are functionalized with biotin molecule. The resulting magnetic nanoparticles with an average diameter of 8nm have a biotin-anchored morphology, which gives an exceptionally high affinity for the Cy3-labeled streptavidin. The spectroscopic and magnetic data results confirmed the presence of the interaction between biotin-anchored Fe3O4 particles and Cy3-labeled streptavidins. These biocompatible magnetic nanoparticles can be used as a basic protocol for various biological applications, particularly linking molecules together to create signal generation systems.
    Chemical Physics Letters 09/2006; 428(1):125-129. DOI:10.1016/j.cplett.2006.06.092 · 1.99 Impact Factor
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    Kwang Seok Oh · Yong Ki Park · Seong Ihl Woo
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    ABSTRACT: Highly reliable 64-channel sequential and parallel tubular reactor for high-throughput screening of heterogeneous catalysts is constructed with stainless steel. In order to have a uniform flow rate at each channel, 64 capillaries are placed between the outlet of multiport valve and the inlet of each reactor. Flow rate can be controlled within ±1.5%. Flow distribution can be easily adjusted for sequential and parallel mode of operation. The reactor diameter is too big to have a uniform temperature distribution. Hence, the reactor body is separated into three radial zones and controlled independently with nine thermocouples. Temperature accuracy is ±0.5 °C at 300 °C and ±1 °C at 500 °C in sequential mode, while it is ±2.5 °C in the range of 250–500 °C in parallel mode. The temperature, flow rate, reaction sequence, and product analysis are controlled by LABVIEW™ software and monitored simultaneously with displaying a live graph. The accuracy in the conversion is ±2% at the level of 73% conversion when all reactors are loaded with same amount of catalyst. A quaternary catalyst library of 56 samples composed of Pt, Cu, Fe, and Co supported on AlSBA-15 (SBA-15 substituted with Al) are evaluated in the selective catalytic reduction of NO at various temperatures with our system. The most active compositions are rapidly screened at various temperatures.
    Review of Scientific Instruments 05/2005; 76(6):062219-062219-7. DOI:10.1063/1.1927076 · 1.58 Impact Factor
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    ABSTRACT: Multichannel superconducting quantum interference device (SQUID) systems based on double relaxation oscillation SQUIDs (DROS) were developed for measuring magnetocardiography (MCG) and magnetoencephalography (MEG) signals. Since DROS provides large fluxto-voltage transfer coeffcients, about 10 times larger than the DC SQUIDs, direct readout of the SQUID output was possible using compact roomtemperature electronics. Using DROSs, we fabricated two types of multichannel systems; a 37-channel magnetometer system with circular sensor distribution for measuring radial components of MEG signals, and two planar gradiometer systems of 40-channel and 62-channel measuring tangential components of MCG or MEG signals. The magnetometer system has external feedback to eliminate magnetic coupling with adjacent channels, and reference vector magnetometers were installed to form software gradiometers. The field noise of the magnetometers is around 3 fT&sol;√Hz at 100 Hz inside a magnetically shielded room. The planar gradiometer systems have integrated first-order gradiometer in thin-film form with a baseline of 40 mm. The magnetic field gradient noise of the planar gradiometers is about 1 fT&sol;cm&sol;√Hz at 100 Hz. The planar gradiometers were arranged to measure field components tangential to the body surface, providing efficient measurement of especially MCG signals with smaller sensor coverage than the conventional normal component measurements.

Publication Stats

292 Citations
97.56 Total Impact Points

Institutions

  • 2012–2014
    • Dongguk University
      Sŏul, Seoul, South Korea
  • 2003–2013
    • Korea Research Institute of Chemical Technology
      • Division of Advanced Material
      Daiden, Daejeon, South Korea
  • 1991–2008
    • Korea Research Institute of Standards and Science
      • • Brain and Cognition Measurement Center
      • • Division of Metrology for Quality LIfe
      Daiden, Daejeon, South Korea
  • 1997–2001
    • Korea University
      • Department of Physics
      Seoul, Seoul, South Korea
  • 1999–2000
    • Yeungnam University
      • Department of Physics
      Gyeongsan, Gyeongsangbuk-do, South Korea
  • 1998
    • Sogang University
      • Department of Physics
      Sŏul, Seoul, South Korea
  • 1992–1997
    • Korea Advanced Institute of Science and Technology
      • Department of Chemical and Biomolecular Engineering
      Sŏul, Seoul, South Korea
    • Seoul National University
      Sŏul, Seoul, South Korea
  • 1996
    • Kyung Hee University
      • Computer Engineering Division
      Seoul, Seoul, South Korea