• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.197-200
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• 1999

The polyacene materials prepared from phenol resine at relatively low temperature(550~75$0^{\circ}C$) show a highly Li-doped state up to $C_2$Li state without liberation of Li cluster. We prepared each polyacenic materials various temperature and investigated electrochemical property. We tried to change the mole ratio of [H]/[C] that was 0.24~0.4 range and finally found that the further discussion of improvements of battery materials. The X-ray structural analyses have shown that this material is essentiallly amorphous with loose structure in molecular size order. This structure ensures that the PAS battery has both reliability on repetitive doping-undoping processes and higher energy density than other batteries. The PAS electrode has been confirmed to show good stability and reversibility.

• 한국전기전자재료학회논문지
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• 제16권8호
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• pp.736-739
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• 2003

We prepared the chalcogenide As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/, Se$\_$75/Ge$\_$25/ thin film. Holographic grating was formed by the He-Ne laser( λ =633 nm). Annealing at 100$^{\circ}C$ and 200$^{\circ}C$ has been used to change the optical property of chalcogenide thin films for holographic grating formation. As the results, large variation of the optical property was generated at the As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/ chalcogenide film. Diffraction efficiency of the As$\_$40/Ge$\_$10/Se$\_$15/S$\_$35/ film has been enhanced about three times

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.468-473
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• 1998

A mathematical model was developed for a continuous re-actor in which free radical polymerization of methyl methacrylate (MMA) occurred. Elementary reactions considered in this study were initiation, propagation, termination, and chain transfers to monomer and solvent. The reactor model took into account the density change of the reactor contents and the gel effect. A control system was designed for a continuous reactor using extended Kalman filter (EKF) based non-linear model predictive controller (NLMPC) to control the conversion and the weight average molecular weight of the polymer product. Control input variables were the jacket inlet temperature and the feed flow rate. For the purpose of validation of the control strategy, on-line digital control experiments were conducted with densitometer and viscometer for the measurement of the polymer properties. Despite the com-plex and nonlinear features of the polymerization reaction system, the EKF based NLMPC performed quite satisfactorily for the property control of the continuous polymerization reactor.

• 아동학회지
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• 제23권4호
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• pp.35-51
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• 2002

This study investigated the expectations Of 186 Korean mothers regarding the self-regulatory behaviors of their l-to 5-year old child. A questionnaire for mothers was prepared which consists of nine categories identified in previous research : safety rules, personal property rules, interpersonal rules, food-related rules, independence requests, self-care rules, family routines, delay, manners, obedience rules, and academic skills and attitude. Data consisted of questionnaires completed by the mothers. Findings were that (1) mothers had high expectations regarding self-regulatory behaviors about safety and independence but low expectations regarding family routines and personal property self-regulation, (2) their expectations increased with age of child, (3) the pattern of expectations did not change with age, and (4) expectations were higher with lower educational background of the mother.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.371-376
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• 2009

The Power Conditioning System is Power Transfer System which make array DC current to the Grid sinusoidal current. These are Low Frequency Transformer Inverter Type, High Frequency Transformer Inverter Type and Transformer-less Type. Low Frequency Transformer Type has a Excellent Isolation property, but doesn't have competitiveness in Size and Cost. Also High Frequency Transformer Type has a good Isolation property but there are many steps in Power transfer Switching. Nowadays, Transformer-less Type inverter change a transformer to DC/DC Converter which is small and cost effective. In this paper shown the DC/DC Converter Transformer-less Type multi-string inverter design and simulation. The Control Algorithm will be introduced and Simulation was accomplished.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.849-852
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• 2006

The lightweight foamed concrete is superior to properties of insulation and light-weight because it is included in many inner pore. So, lightweight foamed concrete used to construction field that need to property of insulation. The property of insulation of lightweight foamed concrete is varied with density. Also, Density is varied with hardening matrix and pore rate. The purpose of the experiment is to know thermal properties of specimen according to the change of density when heating the specimen. As a result of this experiment, the higher density, the lower temperature of mold. this tendency isn't same as ordinary lightweight foamed concrete, and then density 0.9 is expressed most low temperature result also the discontinuity of shape of mold was efficient for the prevention of the temperature rise.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.89-91
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• 2011

This paper is to investigate experimentally the property of strength development on the concrete for 5 years according to the change of a replacement rate of coarse particle cement in order to use coarse particle cement with a fineness of 1 900 ㎠/g that is classified during a grinding process of the OPC production. The result is that as the CC replacement rate increased, the compressive strength was decreased proportionally. but the width of strength reduction was reduced as time passed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.195-198
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• 1999

A technique is investigated for achieving broadband properties by controlling the operation frequency of microstrip antennas. The control is achieved by applying DC bias to the microstrip antenna. Air gap antenna with PZT post is fabricated. by using in C-band. In the case of Air gap antenna, the variation of center frequency was about 16Mhz and the bandwidth was increased up to 123.3% at 15dB, 160.7% at 20dB than before applying DC bias respectively. The change property of frequency in air gap antenna is nearly the same the C-V property in PZT.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.519-522
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• 2000

The correlation of surface morphology and magnetic property of NiFe thin films on Si(001) deposited by RF-magnetron sputter has been investigated, using AFM, XRD and MR measurements. During short field annealing for 15 min, there was no significant change in XRD patterns of NiFe thin films. However, the degree of surface roughness was changed with increasing annealing temperature. With variation of surface roughness, there was significant difference in MR characteristics of NiFe thin films. In the case of as-deposited NiFe thin films(T$\_$G/ = 150$^{\circ}C$) and UFA400 (T$\_$A/ = 400$^{\circ}C$) having smooth surface, good linearity of MR Curve was observed.

• Fibers and Polymers
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• 제5권4호
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• pp.316-320
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• 2004

Waterproof fabrics are seamed and sealed by waterproof sealing tape to prevent water from penetrating through the stitch holes. As this process may change the mechanical properties of breathable waterproof fabric related to its deformation with human body, the changes in mechanical properties were investigated. In both of parallel and perpendicular directions, tensile characteristics were remarkably changed with seaming and sealing processes. The increase of LT and WT means that the clothing sealed by waterproofing tape may produce somewhat discomfort feeling. On the other hand, the bridge of the sewing thread seemed to be reinforced by waterproofing tape. Shear characteristics such as G, 2HG, and 2HG5 gradually increased with seaming and sealing processes in parallel direction. However, they decreased with sealing process in perpendicular direction because the seam line would work as an axis located at the center of the testing range.