• Title/Summary/Keyword: K252a

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Development of Phototactic Test Apparatus Equipped with Light Source for Monitoring Pests (LED광원에 대한 해충 행동반응 monitoring을 위한 주광성 실험장치 개발)

  • Oh, Min-Seok;Lee, Hoi-Seon
    • Journal of Applied Biological Chemistry
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    • v.53 no.4
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    • pp.248-252
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    • 2010
  • This study presented a development of a phototactic apparatus for pest monitoring. We carried out behavioral experiment against various pest species by using the phototactic chamber. Consequently, the phototactic apparatus was confirmed suitable result of behavioral experiment. Therefore, we believed that the test apparatus help to understand the phototactic responses of various pests.

A Study on the Multi Servo Press System Development of Low Velocity Using Serial Communication (시리얼 통신을 이용한 저속의 멀티 서보 프레스 시스템 개발에 관한 연구)

  • Yu, Hwan-Shin;Park, Hyung-Bae
    • Journal of Advanced Navigation Technology
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    • v.18 no.3
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    • pp.248-252
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    • 2014
  • In this paper, press and nut runner used in press-fit or tightening the bolts and nuts at assembling process of automobile parts companies continually demand accuracy and improved productivity. Simultaneous control of production systems through synchronization configuring of the combination multi press-fit system developed multi servo press system using the low-speed serial communication. As a result, the accuracy and the productivity is improved and product quality improvement could be achieved.

A Study on harmonics generation and reduction in Dimmer circuits (Dimmer 회로에서의 고조파 발생과 저감에 관한 연구)

  • Park, Seok-Hoon;Yu, In-Keun
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.252-254
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    • 2000
  • For many years, electric utility has used sustained interruption rates as a reliability index. Today, however, many electricity consumers are adversely affected by more subtle voltage disturbances such as harmonic distortion. This paper deals with observations of events that occur in the Dimmer circuits and phase control which could affect harmonics problem to the commercial power system. In order to reduce the effect of harmonics and design filters, Solid State Relay Dimmer(SCRs or TRIACs) and Noise Filter are described, and the effects of harmonics is also analyzed. IGBT Dimmer which is appropriate method to reduce harmonics and improve efficiency is introduced.

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Studies on the Combustion of Anthracite (III). Studies on the Utilization of the Anthracite Ash (無煙炭 燃燒에 對한 硏究 (第3報). 灰分의 利用에 對한 硏究)

  • Shin Byung-Sik;Shin SeI-Kun
    • Journal of the Korean Chemical Society
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    • v.19 no.4
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    • pp.252-257
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    • 1975
  • This experimental study was carried out to examine the utilization of the anthracite ash as a fertizer. It was found that the ash had very small amount of the soluble matters in 2% citric acid solution therefore it is proved ineffective as a fertilizer. When the small amount of calcinated dolomite was added to the anthracite, it was observed that the resulting ash showed much increased solubility of magnesium, calcium, sulfur and silica etc in the citric acid solution. So it is concluded that the ash of the mixture of anthracite and calcinated dolomite would be one of the useful soil-conditioner and supplyer of nutrients.

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Introduction of Wooden Kagome Structure to the Furniture Design

  • Chung, Woo-Yang;Xu, Hui-Lan
    • Journal of the Korea Furniture Society
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    • v.21 no.3
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    • pp.248-252
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    • 2010
  • This study is carried out to introduce the concept of Kagome structure as the new trial for the furniture design and the feasibility of its utilization in furniture industry. Kagome means originally the two dimensional bamboo-basket woven pattern that is composed of interlaced triangles whose lattice points each have four neighboring points, which was used in traditional bamboo craft design like 'Jukbuin(bamboo-wife)'. Its unique truss structure has been widely used by many kinds of the domain of science and engineering in mechanical and architectural industry with some merits, i,e, material utilization efficiency and robust strength. Here we tried to introduce two dimensional and three dimensional form of Kagome which are supposed to be a furniture design elements. Authors think these Kagome design could be realized with domestic lumber of inferior properties. Both of them would be used as a decorative element or mechanical supporter in furniture design.

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Analysis of Sticking Coefficient in BSCCO Thin Film (BSCCO 박막의 부착계수 해석)

  • Chun, Min-Woo;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.252-255
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    • 2002
  • BSCCO thin films are fabricated by an ion beam sputtering method, and sticking coefficients of the respective elements are evaluated. The sticking coefficient of Bi element in BSCCO film formation was observed to show a unique temperature dependence; it was almost a constant value of 0.49 below about $730^{\circ}C$ and decreased linearly over about $730^{\circ}C$. In contrast, Sr and Ca, displayed no such remarkable temperature dependence. This behavior of the sticking coefficient was explained consistently on the basis of the evaporation and sublimation processes of $Bi_{2}O_{3}$. It was concluded that Bi(2212) thin film constructs from the partial melted Bi(2201) phase with the aid of the liquid phase of $Bi_{2}O_{3}$.

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Suspension Polymerization of Styrene with Tricalcium Phosphate as Stabilizer

  • Hong, Soon-Gil;Park, Moonsoo
    • Macromolecular Research
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    • v.8 no.6
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    • pp.247-252
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    • 2000
  • Suspension polymerizations of styrene were conducted in the aqueous phase with tricalcium phosphate (TCP) as a stabilizer and $\alpha$, $\alpha$'-azobis(isobutyronitrile) (AIBN) as an initiator. Various amounts of initiator and stabilizer were selected and the reaction was carried out at a selected temperature between 60 to 80 $\^{C}$. It was found that the combination of 5 wt% stabilizer and 2.427$\times$10$\^$-3/ mol/L of costabilizer is the minimum amount for suspension polymerization reaction to produce particles in the aqueous phase. Particles were found to be polydisperse in diameter, regardless of reaction conditions. Class transitions were observed to be around 95$\^{C}$, nearly independent of reaction temperature and initiator. Homogenizer was found to be essential in forming particles in the proximity of tens of micrometers in diameter in suspension polymerization with TCP as stabilizer.

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Slot optimization of cage rotor for Inverter-fed 3-phase Induction Motor (인버터 구동 유도전동기의 회전자 슬롯형상 최적화)

  • Kim, Byung-Taek;Kwon, Byung-Il
    • Proceedings of the KIEE Conference
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    • 2000.11b
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    • pp.250-252
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    • 2000
  • A simple analysis method for inverter-fed induction motor using F.E.M and equivalent circuit is proposed. And an optimum shape of rotor slot for 2Hp inverter-fed induction motor is determined by combining the proposed analysis method and an optimization algorithm. Conjugate gradient method is used for the optimization algorithm. The optimization is performed for higher efficiency and reduction of harmonic loss in the inverter-fed induction motor. The optimization results are verified by comparing with those of the time-step F.E.A and the experiment.

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Technology Trends for Photoresist and Research on Photo Acid Generator for Chemical Amplified Photoresist (포토 레지스트의 기술 동향과 화학 증폭형 포토레지스트에서의 광산 발생제의 연구)

  • Kim, Sung-Hoon;Kim, Sang-Tae
    • Journal of Integrative Natural Science
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    • v.2 no.4
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    • pp.252-264
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    • 2009
  • Lithographic data obtained from PHS(polyhydroxy styrene) having various functionalities were investigated by using a photoacid generator based on diazo and onium type. Chemically amplified photoresist based on the KrF type photoresist was developed by using a photoacid generator and multi-functional resin. Thermal stability for the photoacid generator showed that the increase of loading amount of photoacid generator resulted in the decrease of glass transintion temperature (Tg). The photoacid generators having methyl, ethyl, or propyl group in their cationic structure produced T-top structure in pattern profile due to the effect of acid diffusion during the generation of acid in the resist. The increase of carbon chain length in the anionic structure of photoacid generators resulted in lower pattern resolution due to the interruption of acid diffusion.

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Dosimetric evaluation of Tomotherapy and four-box field conformal radiotherapy in locally advanced rectal cancer

  • Yu, Mina;Jang, Hong Seok;Jeon, Dong Min;Cheon, Geum Seong;Lee, Hyo Chun;Chung, Mi Joo;Kim, Sung Hwan;Lee, Jong Hoon
    • Radiation Oncology Journal
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    • v.31 no.4
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    • pp.252-259
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    • 2013
  • Purpose: To report the results of dosimetric comparison between intensity-modulated radiotherapy (IMRT) using Tomotherapy and four-box field conformal radiotherapy (CRT) for pelvic irradiation of locally advanced rectal cancer. Materials and Methods: Twelve patients with locally advanced rectal cancer who received a short course preoperative chemoradiotherapy (25 Gy in 5 fractions) on the pelvis using Tomotherapy, between July 2010 and December 2010, were selected. Using their simulation computed tomography scans, Tomotherapy and four-box field CRT plans with the same dose schedule were evaluated, and dosimetric parameters of the two plans were compared. For the comparison of target coverage, we analyzed the mean dose, $V_{nGy}$, $D_{min}$, $D_{max}$, radical dose homogeneity index (rDHI), and radiation conformity index (RCI). For the comparison of organs at risk (OAR), we analyzed the mean dose. Results: Tomotherapy showed a significantly higher mean target dose than four-box field CRT (p = 0.001). But, $V_{26.25Gy}$ and $V_{27.5Gy}$ were not significantly different between the two modalities. Tomotherapy showed higher $D_{max}$ and lower $D_{min}$. The Tomotherapy plan had a lower rDHI than four-box field CRT (p = 0.000). Tomotherapy showed better RCI than four-box field CRT (p = 0.007). For OAR, the mean irradiated dose was significantly lower in Tomotherapy than four-box field CRT. Conclusion: In locally advanced rectal cancer, Tomotherapy delivers a higher conformal radiation dose to the target and reduces the irradiated dose to OAR than four-box field CRT.