• BMB Reports
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• v.35 no.1
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• pp.67-86
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• 2002

Three routes have been identified triggering neuronal death under physiological and pathological conditions. Excess activation of ionotropic glutamate receptors cause influx and accumulation of $Ca^{2+}$ and $Na^+$ that result in rapid swelling and subsequent neuronal death within a few hours. The second route is caused by oxidative stress due to accumulation of reactive oxygen and nitrogen species. Apoptosis or programmed cell death that often occurs during developmental process has been coined as additional route to pathological neuronal death in the mature nervous system. Evidence is being accumulated that excitotoxicity, oxidative stress, and apoptosis propagate through distinctive and mutually exclusive signal transduction pathway and contribute to neuronal loss following hypoxic-ischemic brain injury. Thus, the therapeutic intervention of hypoxic-ischemic neuronal injury should be aimed to prevent excitotoxicity, oxidative stress, and apoptosis in a concerted way.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.43-46
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• 1995

Adaptive algorithms based on gradient adaptation have been extensively investigated and successfully jointed with active noise/vibration control applications. The Filtered-X LMS algorithm became one of the basic feedforward algorithms in such applications, but still is not fully understood. The error path model effect on the Filtered-X LMS algorithm has been under the investigation and some useful properties related stability has been discovered. We are interested in utilizing the fact that the model error caused by the way optimizing the error path model in a view point of convergence speed of Filtered-X LMS algorithm for pure tone noise suppression application without any performance loss at steady state.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.17-20
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• 2001

In this paper, film bulk acoustic resonator(FBAR) with an air-gap is fabricated by removing ZnO sacrificial layer and its characteristics as a various dimension of ZnO sacrificial and piezoelectric layer is evaluated. The center frequency of the FBAR device with the ZnO film is about 1.9 GHz. Because of mass-loading effect, a dimension of sacrificial layer and piezoelectrc layer affect frequency response such as center frequency, insertion loss, band separation, attenuation and so on.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2029-2032
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• 2014

Magnetically nano-$CoFe_2O_4$ efficiently catalyzes oxidation of primary and secondary benzylic and aliphatic alcohols to give the corresponding carbonyl products in good yields. The reactions were carried out in an aqueous medium at room temperature in the presence of oxone (potassium hydrogen monopersulfate) as an oxidant. In addition, the catalysts could be reused up to 6 runs without significant loss of activities. Catalyst was characterized by SEM, XRD and IR.

• Journal of the Semiconductor & Display Technology
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• v.5 no.1 s.14
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• pp.45-49
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• 2006

In this paper, a new method that monitors the quantity of particles using ion-counter in vacuum environment is introduced. In-situ particle monitoring (ISPM) system is composed by Gerdien type ion-counter (house-made), DC power supply and electrometer. The ion-counter applied by positive voltage detects only positive charged particles. Therefore the particles to be detected should be in known charge state for further data analysis. ion-counter is installed at the exhaust line of process equipment where the pressure loss is structurally low. ISPM system performance has been verified with SMPS (Scanning Mobility Particle Sizer) system. The correlation coefficient is above 0.98 at the particle size range of $20{\sim}300nm$ in diameter with identified charge distribution under $0.1{\sim}10.0$ Torr.

• Archives of Reconstructive Microsurgery
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• v.12 no.2
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• pp.99-104
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• 2003

Liposuction is a useful method for debulking free flap. Recently, ultrasound assisted liposuction(UAL) has been reported to have many advantages over conventional suction-assisted lipectomy. We applied the UAL to debulk free fasciocutaneous flap of the forehead and lower extremities. The result was satisfactory and there was no significant complications worth noting. Although the cost can be expensive, it has many advantages such as less blood loss, larger amount of fat aspirate and better skin contraction. We can conclude that UAL can be a useful alternative method to debulk free fasciocutaneous flap.

• Korean Journal of Veterinary Research
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• v.55 no.1
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• pp.65-69
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• 2015

A 14-year-old, 7.4 kg, neutered male mongrel dog presented with vomiting, anorexia, and hematuria starting 3 days prior to admission. Serum biochemical profiles indicated severe azotemia. Computed tomography revealed loss of normal left kidney structure. The organ was 1.5 to 2 times larger than the right kidney with mixed attenuation. Histopathologic examination was performed after nephrectomy. The renal mass and mesenteric membrane were positive for vimentin and stained blue with Masson's trichrome. In conclusion, this was a rare occurrence of primary renal fibrosarcoma, most likely originated from the renal capsule, with local invasion into the mesenteric membrane.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.218-220
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• 2003

In this paper, tile SMD isolator for IMT-2000 handset is designed, fabricated and analyzed. We have designed the SMD isolator using EM Simulation tool. Electrical results have improved in comparison with a conventional model. It provides an insertion loss of 0.3 dB at 1.95GHz and an isolation of 21.5 dB or more over a frequency range of 1.92 through 1.99 GHz. The size of the isolator is $4\times4\times1.8mm^3$.

• Carbon letters
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• v.13 no.4
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• pp.226-229
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• 2012

Polyacetylene (PA) films with vertically aligned fibril morphology were synthesized in homeotropic nematic liquid crystal (N-LC) solvent by using a magnetic field of 5 Tesla as an external perturbation. Scanning electron microscope (SEM) photographs indicated that the lengths of fibrils from the substrate were $5-35{\mu}m$, depending on polymerization time. Carbonization was carried out using iodine-doped PA film and a morphology-retaining carbonization method. From the SEM results, we confirmed that the vertical morphology of the PA remains unchanged even after carbonization at $800^{\circ}C$. The weight loss of the films due to carbonization at $800^{\circ}C$ is about 20% of the weight of the film before iodine doping. It is expected that vertically aligned carbon might be a precursor for preparing vertical graphite materials, which materials could be useful for electrochemical energy storage and cell electrodes.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.333-337
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• 2003

In this paper, 5.2 GHz WLAN BPF(Band Pass Filter) using LTCC(Low temperature co-firing ceramic) Multilayer technology was simulated and manufactured. A DGS(Defected Ground structure) resonator with spiral ground pattern is used to shorten resonator size and improve circuit Q factor. And the equivalent circuit of BPF was suggested. The measured result shows good agreement with simulated data. Experimental results show the center frequency of 5.25GHz, the insertion loss of 0.14dB, and the 3-dB bandwidth of 350MHz (6%). The center frequency of BPF is 5.25GHz which is available for wireless LAN.