• Journal of the Korean Electrochemical Society
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• v.7 no.2
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• pp.100-107
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• 2004

The nano or micro sized structures of conducting polymer had been prepared by synthesizing the desired polymer within the pores of template of nano or micro porous membrane filter. In this study, we had tried to fabricate conducting polymer microstructures on an electrode by using electrochemical deposition adopting template synthesis. Our attention was focused on two different things, attaching template on the electrode and fabricating microstructures only at limited areas of the electrode. A conducting polymer, PEDiTT (poly 3,4-ethylenedithi-athiophene) solution was blended with PVA(polyvinyl alcohol) solution and used as an conducting adhesive. After attaching template membrane, the electrode were immersed in 0.5M pyrrole in 0.1M KCI solution, and electrochemical polymerization was performed. The growth process of the microstructures studied by SEM. The electrochemical fabrication of conducting polymer was performed by using two-electrode system. A large working electrode and a micro scale disc electrode were used for the confined area synthesis. Polymerization potential was 4V in an electrolytic solution made of KCI in deionized water. The optimum polymerization conditions were, i.e. (4V/100sec) for $250{\mu}m$ electrode and (6V/30 sec) for $10{\mu}m$ electrode.

• Elastomers and Composites
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• v.49 no.2
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• pp.103-109
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• 2014

Blends of emulsion SBR (E-SBR) and solution SBR (S-SBR) were prepared, and their microstructures (styrene, 1,2-unit, cis-1,4-unit, and trans-1,4-unit contents) were analyzed by Fourier transform infrared spectroscopy (FTIR) with transmittance mode. Method to measure absorbance by valley-to-valley baseline (TV) is objectively reasonable, but has a demerit which peak intensity of the cis-1,4-unit cannot be correctly measured. In order to obtain information for the four microstructures including cis-1,4-unit, measurement methods without correction (TM) and correction to 99% transmittance (TB) were compared to the TV method. Results obtained by the TB method were closer to those obtained by the TV one than those obtained by the TM. The microstructures were determined from the absorbances obtained by the TM and TB methods according to the ISO/FDIS 21561:2005(E). Variations of the styrene, 1,2-unit, and trans-1,4-unit contents with the blend ratio of E-SBR/S-SBR showed relatively good linearities, and there was no big difference between results obtained by the TM and TB methods. Variations of the cis-1,4-unit content with the blend ratio absolutely did not show linearities irrespective of the TM and TB methods.

• 전자공학회논문지 IE
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• v.47 no.4
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• pp.1-9
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• 2010

This paper describes a ultrasonic signal processing front-end IC for distance range meter and body detector. The burst shaped ultrasonic signal is generated by a self oscillator and its frequency range is about 40[kHz]-300[kHz]. The generated ultrasonic signal transmit through piezo resonator. The another piezo device transduce from received ultrasonic signal to electrical signals. This front-end IC contained low noise amplifier, band pass filter, busrt detector and time pulse generator and so on. This IC has two type of new idea for improve function and performance, which are self frequency control (SFC) and Variable Gain Control amplifier (VGC) scheme. The dimensions and number of external parts are minimized in order to get a smaller hardware size. This device has been fabricated in a O.6[um] double poly, double metal 40[V] High Voltage CMOS process.

• Korean journal of food and cookery science
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• v.7 no.1
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• pp.53-59
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• 1991

The purpose of this study is to investigate textural characteristics of egg solution coagulated with steamer and microwave oven, and egg solution diluted various concentration of it with water or milk. Textural Characteristics of the samples were evaluated by the Sensory test and Rheometer. The results obstained were as follow; 1. Rheometer measurement indicated that the thicker is concentration of egg solution, the harder is samples 2. In sensory evaluation on the various concentration of egg solution, the panels on the overall quality showed the most favorite tendency that the sample diluted with 50% of water and the one with 70% of milk in use steamer; the sample diluted with 30% of water and the one with 70% of milk in use microwave oven.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.4
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• pp.494-499
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• 2007

In this paper we realized a system, if a user selects the area of the important parts or the arrangement parts when he reads the books or the papers, which amends, stores and readjusts the characters that are included in the selected area by outputting the characters to the word processor in sequence. If a user selects what he wishes lot with his finger, the system detects the movement of the finger by applying the hand recognition algorithm and recognizes the selected area. The system converts the distance of the width and the length of the selected area to the number of the pulse, and controls the motor to move the camera at the position. After the system scales up/down the zoom to be able to recognize the character and controls the focus to the regulated zoom closely, it controls the focus in detail to get more distinct image by using the difference of the light and darkness. We realize the recognition and editing support system of korean language that converts the obtained images to the document by applying the character recognition algorithm and arrange the important parts.

• Progress in Medical Physics
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• v.10 no.1
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• pp.17-22
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• 1999

INJ-I, INJ-E, PFN, BMI, and PRF were selected among the various factors which constitute a digital linear accelerator to find effects on the dose distribution by changing current and voltage within the permitted scale which Mevatron automatically maintained. We measured the absorbed dose using an ion chamber, analyzed the waveform of beam output using an oscilloscope, and measured symmetry and flatness using a dosimetry system. An RFA plus (Scanditronix, Sweden) device was used as a dosimetry system. Then an 0.6cc ion chamber (PR06C, USA), an electrometer (Capintec192, USA), and an oscilloscope (Tektronix, USA) were employed to measure the changes on the dose distribution characteristics by changing the beam-tuning parameters. When the currents and the voltages of INJ-I, INJ-E, PFN, BMI, and PRF were modified, we were able to see the notable change on the dose rate by examining the change of the output pulse using the oscilloscope and by measuring them using the ion chamber. However, the results of energy and flatness graph from RF A plus were almost identical. The factors had fine differences: INJ-I, INJ-E, PFN, BMI, and PRF had 0.01∼0.02% differences in D10/D20, 0.1∼0.2 % differences in symmetry, and 0.1∼0.4% differences in flatness. Since Mevatron controlled itself automatically to keep the reference value of the factor, it was not able to see large differences in the dose distribution. There were fine differences on the dose rate distribution when the voltage and the currents of the digitized factors were modified Nonetheless, a basic operational management information was achieved.

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.319-326
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• 1993

The effects of $SnO_2$ crystallite size on the powder characteristics, the resistance in air and the sensitivity to 0.5 vol % $H_2$, CO-air mixture were observed. The size of SnO, powder was controlled by calcining temperature variation ($500^{\circ}C$ ~$1100^{\circ}C$) of $\alpha$-stannic acid fabricated from $SnCl_4 \cdot xH_2O$. Its crystallite size. evaluated from TEM image, was in the range of 8-54nm. With the reduction of crystallite size, the adsoption peak of $H_2O$ on FTIR curve became more clear while the lattice parameters were invariable. As the crystallite size decreased, with elements of thick film, the temperatures showing a minimum resistance in air and a maximum sensitivity to H, gas reduced. The temperature variations were assigned to the changes of activation energy of the active adsorbates, and it was suggested that the decrease of activation energy can be one of the reasons for the' sensitivity increase with the' fine powder.

• Resources Recycling
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• v.12 no.6
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• pp.26-31
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• 2003

The power loss characteristics of Mn-Zn ferrite were observed with the sintering temperature. In case of $1150 ^{\circ}C$ sintering, the core loss increased with measuring temperature, and does not have minimum value at the point where the magnetocrystalline anisotropy be 'zero'. This reason mainly due to the change of core loss mechanism with grain size which affects residual loss. The grain size and sintered density slightly increased with equilibrium oxygen partial pressure at$ 1150 ^{\circ}C$ sintering. The resistivity and initial permeability showed no significance with atmosphere, these results due to complex effect of $Fe^{2+}$ concentration and microstructure change. The core loss at $100^{\circ}C$ decreased as the equilibrium oxygen partial pressure increased.e increased.

• Journal of IKEEE
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• v.3 no.2 s.5
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• pp.250-258
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• 1999

This paper presents a decentralized adaptive controller design for a Magnetically Levitated Fine Manipulator to follow the given trajectory as close as possible in spite of coupling effects between motion axes(degree of freedoms or subsystems). The present controller consists of two parts: the model reference controls based on known subsystems and the local adaptive controls. The former stabilizes the motion of the manipulator so as to follow that of the reference model. The latter reduces tracking errors due to coupling disturbances by adjusting the local gains to such levels that override interactions and assure the stability of the overall system. Through several experimental results, it has been shown that the decentralized adaptive control scheme has better tracking performances comparing to the PID controller case as well as good disturbance(coupling) rejection property.

• Korean Journal of Head & Neck Oncology
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• v.18 no.1
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• pp.65-70
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• 2002

Background and Objectives: Recently the tenn 'papillary microcarcinoma' has been proposed to designate carcinoma of 10 mm or less in diameter. In some cases, cervical lymph node metastasis preceding the occurrence of the primary tumor may be the first and sole manifestation of the disease. The objective of this study is to assess the clinical features of cervical metastasis in papillary microcarcinoma of thyroid glands. Materials and Methods: 9 cases with papillary microcarcinoma with neck metastasis were analyzed retrospectively. 5 cases are men and 4 are women. All patients complained of painless, movable neck mass. The symptom had been present from 1 month to 36 months. We reviewed clinical history, imaging studies, the results of fine needle aspiration, the surgical method, the pathologic results. Results: In 9 cases, no abnormalities of the thyroid gland were shown by imaging studies and thyroid scan. 3 cases were diagnosed by fine needle aspiration cytology. the others were not. Total thyroidectomy and neck dissection were performed in 9 cases and then pathology reports showed 2 case of multiple, 2 case of contralateral single and 5 cases of unilateral single thyroid microcarcinoma. They have no recurrence during follow-up period. Conclusions: Cervical metastasis from papillary microcarcinoma is variable clinical manifestation. The diagnosis of cervical metastasis from papillary microcarcinoma should be considered in patient with neck mass. We recommend total thyroidectomy with neck dissection and postoperative radioactive iodine ablation therapy in neck metastasis from papillary thyroid microcarcinoma.