• 한국산림과학회지
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• 제105권2호
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• pp.231-237
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• 2016

본 연구는 국내 벌채현장에서 가장 많이 활용되고 있는 Woodgrab에 의한 단목집재작업이 생산성 및 수익성 측면에서 가장 유리한 방식인가에 대한 검토를 하고자 수행되었다. 이를 위해 Woodgrab 목재수확방법의 생산성 및 수익성을 비교하기 위하여 Swing yarder와 Tower yarder에 의한 전목집재작업을 선정하였다. 이를 토대로 낙엽송 임분에 대한 작업기종별 조재지침을 적용하여 각 기종별 수확작업과정에 따른 작업비용과 등급별 원목매각 순수익을 산출하여 비교하였다. 연구결과, Woodgrab을 이용한 단목집재작업은 Swing yarder 혹은 Tower yarder에 의한 전목집재작업에 비해 생산성이나 생산단가 측면에서 유리한 반면 원목생산의 수익성 측면에서는 오히려 불리한 것으로 나타났다. 이것은 Woodgrab에 의한 목재생산작업을 하는 경우 생산비가 절감되는 대신 시장가격이 낮은 펄프, 보드류 혹은 톱밥 등의 원료재로 사용되는 단목을 주로 생산할 수 밖에 없는 것에 기인한 것이다.

• 멤브레인
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• 제4권1호
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• pp.1-8
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• 1994

There are growing needs to produce relatively high purity(99.0% or higher) oxygen at low cost. For small scale production, both pressure swing adsorption(PSA) and membrane process are competitive and less expensive or more convenient than well known cryogenic fractionation technology. A continuous membrane column(CMC) combined with a PSA oxygen generator can be employed to produce high purity oxygen continuously. The oxygen enriched gas generated by a PSA unit, with a concentration of 93~94%, is fed to the CMC that consism of three modules of poly(imide) hollow fibers. Several experiments were conducted by varying parameters, such as feed flow rate, transmembrane pressure drop, stage cut, and feed location in order to obtain a high oxygen concentration above 99.0%. A two-series unit mode was also employed with CMC operation to optimize the given membrane area.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.36-36
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• 2009

In this work, we describe a method to fabricate the Pt-silicided SB-MOSFETs with a n-type Silicon-On-Insulator (SOI) substrate as an active layer and demonstrate their electrical and structural properties. The fabricated SB-MOSFETs have novel structure and metal gate without sidewall. The gate oxide with a thickness of 7 nm was deposited by sputtering. Also, this fabrication processes were carried out below $500^{\circ}C$. As a result, Subthreshold swing value and on/off ratio of Fabricated SB MOSFETs was 70 [mV/dec] and $10^8$.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1003-1006
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• 2004

We have fabricated poly-Si TFTs at 170$^{\circ}C$ using inductively coupled plasma chemical vapor deposition (ICP-CVD) and excimer laser annealing (ELA). A Poly-Si film with large grains exceeding 5000${\AA}$ and a $SiO_2$ film with high breakdown field are deposited by ICP-CVD. A high mobility exceeding 100$cm^2$/Vs with a low sub-threshold swing of 0.76V/dec was obtained.

• 한국재료학회지
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• 제26권12호
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• pp.676-680
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• 2016

We have investigated the properties of thin film transistors(TFT) fabricated using zinc tin oxide(ZTO) thin films deposited via on-axis sputtering and FTS methods. ZTO thin films deposited by FTS showed lower root-mean-square(RMS) roughness and more uniformity than those deposited via on-axis sputtering. We observed enhanced electrical properties of ZTO TFT deposited via FTS. The ZTO films were deposited at room temperature via on-axis sputtering and FTS. The as-deposited ZTO films were annealed at $400^{\circ}C$. The TFT using the ZTO films deposited via FTS process exhibited a high mobility of $12.91cm^2/V.s$, a low swing of 0.80 V/decade, $V_{th}$ of 5.78 V, and a high $I_{on/off}$ ratio of $2.52{\times}10^6$.

• 전기학회논문지P
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• 제62권2호
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• pp.84-89
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• 2013

In this paper, we propose interface circuits for reducing power consumption and EMI when sequences of data from LCD controller to LCD driver IC by transmitting two bit data during one clock period. The proposed circuits are operated in current mode, which is different from conventional voltage-mode signaling techniques, and also employ threshold technique of Modified-LVDS(Low Voltage Differential Signaling) method. We have simulated the proposed circuits using H-SPICE tool for performance analysis of the proposed method. The simulation results show that the proposed circuits provide a faster transmission speed and stronger noise immunity than the conventional LVDS circuits. It might be suitable for the real-time transmission of huge image data in LCD system.

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.759-766
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• 2003

The amount of container freight continuously has been increased. and the low efficiency of container crane causes jamming frequently in transportation and cargo handling at port. The conventional control techniques based on a mathematical model are not well suited for dealing with ill-defined and uncertain systems. Recently. Fuzzy control has been successfully applied to a wide variety of practical problems as robots. automatic train operation system. etc. In this paper. a fuzzy controller for container crane is proposed to accomplish a design of improved control system for minimizing the swing motion at destination. In this scheme a mathematical model for the system is obtained in state space form. Finally. to exhibit the tracking performance and robustness of the proposed controller. computer simulations were carried out with various references, parameter variations and disturbances.

• JSTS:Journal of Semiconductor Technology and Science
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• 제16권5호
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• pp.630-634
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• 2016

We report the computer aided design results for a GaSb/InAs broken-gap gate all around nanowire tunneling FET (TFET). In designing, the semi-empirical tight-binding (TB) method using $sp3d5s^*$ is used as band structure model to produce the bulk properties. The calculated band structure is cooperated with open boundary conditions (OBCs) and a three-dimensional $Schr{\ddot{o}}dinger$-Poisson solver to execute quantum transport simulators. We find an device configuration for the operation voltage of 0.3 V which exhibit desired low sub-threshold swing (< 60 mV/dec) by adopting receded gate configuration while maintaining the high current characteristic ($I_{ON}$ > $100 {\mu}A/{\mu}m$) that broken-gap TFETs normally have.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.356-356
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• 2010

In this paper, Poly silicon thin-film transistors (poly-Si TFTs) with employed the SPC (Solid phase crystallization) and ELA (Excimer laser annealing) methods on glass panel substrate are fabricated to investigate the electrical poperies. Poly-Si TFTs have recess-channel structure with formated source/drain regions by LPCVD n+ poly Si in low $650^{\circ}C$ temperature. the ELA-TFT show higher on/off current ratio and subthreshold swing than a-Si and SPC TFT that therefore, these results showed that the ELA-TFT might be beneficial for practical embedded TFT memory device application.

• The Journal of Korean Physical Therapy
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• 제21권1호
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• pp.35-40
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• 2009

Purpose: The purpose of this study was to investigate change of muscle activities during level walking, stairs and ramp climbing in old adults. Methods: Twelve old adults were recruited and agreed this study. Muscle activity was measured by MP150 system (BIOPAC System Inc., Santa Barbara, USA). Statistical analysis was used one-way ANOVA to know the difference according to gait conditions (level walking, stairs and ramp ascending) Results: In stance phase, muscle activities of low extremities with old adults were generally significant difference in ramp ascending. In swing phase, rectus femoris and biceps femoris activity in old adults generally more increased during stairs ascending and tibialis anterior and gastrocnemius activity in old adults generally increased during ramp ascending. Conclusion: These results indicate that stair and ramp climbing is different muscle recruit pattern to level walking.