• Title/Summary/Keyword: non-ideal characteristic

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Implementing Software Risk Management Process based on CMMI (CMMI기반의 소프트웨어 리스크 관리 프로세스 구축)

  • Do, Sung-Ryong;Han, Hyuk-Soo
    • Journal of Convergence Society for SMB
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    • v.1 no.1
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    • pp.45-53
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    • 2011
  • There are always many kinds of risks in software development such as frequent changes of requirements. Especially those risks related to the software characteristic of non-visibility can be threat to the project success. That lead us to the need of process implementation to reduce and minimize those risks. Although, most of the organization recognizes the importance of risk management, actual implementation requires professional knowledge in this area. CMMI, the de facto standard in process reference model, also emphasizes on risk management process area but only provides goals and practices to be implemented, not detail procedure and methods. In this paper, we developed Risk management implementation model based on IDEAL, the process improvement model based on CMMI. The proposed model will help the organizations to implement risk management process which is proper to their situation in the factor of organization size and project characteristics.

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Finite Element Analysis of Porthole Extrusion Process for Al Suspension Arm (서스펜션 암의 포트홀 다이 압출공정 유한요소 해석)

  • Joe, Y.J.;Lee, S.K.;Kim, B.M.;Oh, K.H.;Park, S.W.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2006.05a
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    • pp.247-250
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    • 2006
  • The growing demand for more fuel-efficient vehicles to reduce energy consumption and air pollution is a challenge for the automotive industry. The characteristic properties of aluminum, high strengrth stiffness to weight ratio, good formability, good corrosion resistence, and recycling potential make it the ideal candidate to replace heavier materials in the car to respond to the weight resuction demand within the automotive industry. In this paper, A series of compression test was carried out to find the flow stress of A6082 at 300, 400 and $500^{\circ}C$, then we tried to estimate weldability, extrusion load and effective stress of die in the aluminum extrusion process through the 3D FE simulation at non-steady state for aluminum automotive parts.

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Vaporization Characteristics of Dodecane Fuel Droplet in Supercritical Condition (도데케인 연료액적의 초임계 상태 기화 특성)

  • Ko, J.B.;Lee, K.H.;Koo, J.Y.;Jeon, C.S.;Moon, H.J.
    • Journal of ILASS-Korea
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    • v.9 no.3
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    • pp.8-14
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    • 2004
  • Characteristics of droplet vaporization at high ambient pressures and temperatures which are supercritical conditions is studied numerically by formulating one dimensional vaporization model in liquid dodecane and air. Modified Soave-Redlich-Kwong state equation is used to condider real gas effect. Non-ideal behavior of properties at near critical and supercritical conditions is considered in the high pressure condition. Characteristic spatial distribution of properties with various conditions of pressure and temperature is evaluated in order to understand vaporizing evolution.

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A Study on the Design of Active Filters Using Current Conversion Type Generalized Immittance Converter (전류변환 GIC를 사용한 능동 여파기의 설계 연구)

  • 심수보
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.18 no.2
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    • pp.14-21
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    • 1981
  • This paper describes a method for realizing RC active filters, by the use of the CGIC's In realizing the CGIC circuit, every element in the circuit is selected so as to minimize the effect of the non -ideal characteristic of operational amplifers, and an extra element is added to the, CGIC circuit to compensate the parasitic capacitances of the circuit. The CGIC s are utilized in the design of active filters using ladder embedding technique. The design procedure is presented in detail and the application is illustrated by the design of a band-pass filter of high order.

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A Study on Fire-proof Characteristics of Ultra High Strength Concrete Using Polyamide Fiber (폴리아미드섬유를 사용한 초고강도 콘크리트의 내화성능에 관한 연구)

  • Lee, Soo-Choul;Jeon, Joong-Kyu;Jeon, Chan-Ki
    • Journal of the Society of Disaster Information
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    • v.7 no.4
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    • pp.286-293
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    • 2011
  • Accordingly architectural structure is getting high-rise and bigger, a use of high strength and high performance concrete has been increased. High performance concrete has cons of explosion in a fire. This explosion in the fire can cause the loss of the sheath on a concrete surface, therefore it effects that increasing a rate of heat transmission between the steel bar and inner concrete. Preventing this explosion of high performance concrete in the fire, many kinds of researches are now in progressing. Typically, researches with using polypropylene-fiber and steel-fiber can prove controling the explosion, but the reduction of mobility was posed as a problem of workability. Consequently, to solve the problem as mentioned above, concrete cans secure fire resisting capacity through the using of coating liquid, including Ester-lubricant and non-ionic characteristic surfactant. This research has been drawn a ideal condition in compressive strength areas of concrete by an experiment. When applying 13mm of polyamide fiber, proper fiber mixing volume by compressive strength areas of concrete more than 2.5kg in 160MPa. These amount of a compound can control the explosion.

Operation Characteristic Analysis of a Comb Actuator due to a Anisotropy Variation in RIE Etching (RIE 식각시 발생하는 비등방도 변화에 따른 머리빗형 액튜에이터의 동작 특성 분석)

  • Kim, Bong-Soo;Park, Ho-Jun;Pak, Jung-Ho
    • Journal of Sensor Science and Technology
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    • v.8 no.5
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    • pp.368-376
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    • 1999
  • This paper predicts the changes in the spring constant, the resonant frequency, the electrostatic force, and the displacement of a resonant structure due to non-ideal anisotropic RIE etching process. First, a $6\;{\mu}m$ thick polysilicon was etched by RIE and the anisotropy of the etched structure was measured as a function of a RF power, a $Cl_2$ flow rate and a chamber pressure. In the experimental results, an anisotropy was decreased as the RF power, the $Cl_2$ flow rate, or the chamber pressure was increased. A comb actuator's operation characteristic was predicted depending on the anisotropy variations in RIE etching. Comb actuators with three different support beam structures were investigated : fixed-fixed, crab-leg, and double crab-leg. As the RIE etch anisotropy becomes non-ideal, i.e. the cross section becomes rather a trapezoidal than a rectangular shape, it decreases spring constant, resonant frequency and electrostatic force of a comb actuator but it increases the displacement of the mass. Among the three structures, the comb actuator with double crab-leg support beams is more influenced by anisotropy variation in RIE etch than other two.

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Full Parametric Impedance Analysis of Photoelectrochemical Cells: Case of a TiO2 Photoanode

  • Nguyen, Hung Tai;Tran, Thi Lan;Nguyen, Dang Thanh;Shin, Eui-Chol;Kang, Soon-Hyung;Lee, Jong-Sook
    • Journal of the Korean Ceramic Society
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    • v.55 no.3
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    • pp.244-260
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    • 2018
  • Issues in the electrical characterization of semiconducting photoanodes in a photoelectrochemical (PEC) cell, such as the cell geometry dependence, scan rate dependence in DC measurements, and the frequency dependence in AC measurements, are addressed, using the example of a $TiO_2$ photoanode. Contrary to conventional constant phase element (CPE) modeling, the capacitive behavior associated with Mott-Schottky (MS) response was successfully modeled by a Havriliak-Negami (HN) capacitance function-which allowed the determination of frequency-independent Schottky capacitance parameters to be explained by a trapping mechanism. Additional polarization can be successfully described by the parallel connection of a Bisquert transmission line (TL) model for the diffusion-recombination process in the nanostructured $TiO_2$ electrode. Instead of shunt CPEs generally employed for the non-ideal TL feature, TL models with ideal shunt capacitors can describe the experimental data in the presence of an infinite-length Warburg element as internal interfacial impedance - a characteristic suggested to be a generic feature of many electrochemical cells. Fully parametrized impedance spectra finally allow in-depth physicochemical interpretations.

Can oliceridine (TRV130), an ideal novel µ receptor G protein pathway selective (µ-GPS) modulator, provide analgesia without opioid-related adverse reactions?

  • Ok, Hwoe Gyeong;Kim, Su Young;Lee, Su Jung;Kim, Tae Kyun;Huh, Billy K;Kim, Kyung Hoon
    • The Korean Journal of Pain
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    • v.31 no.2
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    • pp.73-79
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    • 2018
  • All drugs have both favorable therapeutic and untoward adverse effects. Conventional opioid analgesics possess both analgesia and adverse reactions, such as nausea, vomiting, and respiratory depression. The opioid ligand binds to ${\mu}$ opioid receptor and non-selectively activates two intracellular signaling pathways: the G protein pathway induce analgesia, while the ${\beta}$-arrestin pathway is responsible for the opioid-related adverse reactions. An ideal opioid should activate the G protein pathway while deactivating the ${\beta}$-arrestin pathway. Oliceridine (TRV130) has a novel characteristic mechanism on the action of the ${\mu}$ receptor G protein pathway selective (${\mu}$-GPS) modulation. Even though adverse reactions (ADRs) are significantly attenuated, while the analgesic effect is augmented, the some residual ADRs persist. Consequently, a G protein biased ${\mu}$ opioid ligand, oliceridine, improves the therapeutic index owing to increased analgesia with decreased adverse events. This review article provides a brief history, mechanism of action, pharmacokinetics, pharmacodynamics, and ADRs of oliceridine.

KVN Performance Evaluation of Simultaneous 4CH Observations

  • Jung, Dawoon;Sohn, Young-Jong;Byun, Do-Young;Jung, Taehyun
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.74.2-74.2
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    • 2016
  • It is important to know how well observation errors are removed in the calibration process prior to ensuing scientific research. In mm-VLBI observations, a radio wave suffers from an atmospheric propagation delay due to the rapid change of atmospheric refraction. It makes phases of VLBI correlation output fluctuate rapidly, which essentially decreases the coherence of phases and reduces the integration time. Consequently, it is challenging to achieve a high signal-to-noise ratio and enhance the quality of scientific output. Among the causes of the atmospheric propagation delay, water vapor in the troposphere is the most decisive factor to affect phase errors in the high frequency range (> 10GHz). It is expected to have the non-dispersive characteristic that enables to introduce new calibration strategy, Frequency Phase Transfer (FPT). This new method utilizes low frequency phases to compensate phase errors in high frequency bands. In addition, Korean VLBI Network (KVN) which benefits from the simultaneous 4-channels (22/43/86/129 GHz) observations is ideal to probe FPT performance. In order to evaluate FPT performance of KVN, we present the results of FPT phase analysis and discuss its performance.

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Iterative Decoding Performance for Gray Coded QAM Signals with I/Q Phase Unbalance (I/Q 위상 불균형을 동반한 Gray 부호화된 QAM 신호의 반복 복호 성능)

  • Kim Ki-Seol;Park Sang-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6A
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    • pp.611-616
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    • 2006
  • In this paper, we propose a practical implementation method of a soft bit decision expression for an R-QAM (Gray coded Rectangular Quadrature Amplitude Modulation) signal based on the Max-Log-MAP algorithm. The parameters of the soft decision expression for the practical implementation can be obtained with simple arithmetic functions associated with some deterministic parameters such as a received value, distances between symbols, and the order of modulation on a signal space. Also, we analyze the performance of an iterative decoding scheme for the QAM signal with I/Q phase unbalance. The unbalance results from the non-ideal characteristic of components such as a phase shifter between in-phase and quadrature paths for quadrature modulator/demondulator.