• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.66.4-66
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• 2002

In this paper, coefficient diagram method is applied to a center position controller design of the web. The significant property of this controller is the designer can design the controller simultaneously a good balance of stability, response, and robustness. Manabe's CDM is useless for designing high-order plant. We proposed a modified CDM which can be called as approximated pole placement method. The practicality of the proposed method is shown through computer simulation.

• 한국정밀공학회지
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• 제32권5호
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• pp.441-446
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• 2015

Chattering during the milling process causes severe problems on both the workpiece and cutting tools. However, chatter vibration is the inevitable phenomenon that operators require the prediction before the process or monitoring system to avoid the chatter in real-time. To predict the chatter vibration with the stability lobe diagram, the dynamic parameters of machine tool are extracted by considering cutting conditions and adapting the material properties. In this study, experimental verifications were taken for various aluminum types with different feed rates to observe the effect of the key parameters. The comparison between experimental results and the predictions was also performed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 B
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• pp.455-457
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• 1998

This paper designs a noise controller for the small cavity using Coefficient Diagram Method(CDM). In the small cavity system, there exist nonlinear characteristics such as uncertain-time delay and parameter variation. In the controller design of nonlinear system with uncertainty need to the higher order controller or complexity computation. The coefficient diagram is convenient implementation of the control system design method, that is utilized as a vehicle to collectively express the important features of the system and an improved version Kessler's standard form and the Lipatov stability condition of a constitutes the theoretical basis. Simultaneously, it is provided a desired specification, such as the robustness, the stability, faster response, and lower order controller. A simulation of the system with the proposed controller shows sufficient noise cancelation in small cavity.

• 한국지반공학회논문집
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• 제40권2호
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• pp.55-64
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• 2024

쉴드공법은 국제적인 사례에서 그 안정성을 입증한 반면, 경제적 효율성을 지닌 것으로 알려진 NATM 터널 굴착공법은 피복이 얕고 지반이 풍화되며 지하수가 많은 도심지에 적용 시 어려움을 겪고 있다. 본 논문에서는 도심지의 풍화된 암반층과 미고결 사질토 지반에서 발생할 수 있는 전형적인 두 가지 붕락 사례를 소개하고, 여섯 가지 안정성 평가 방법으로 두 붕락 사례를 분석하였으며, 그 결과를 종합하여 육각형의 다이어그램에 의한 방법으로 터널의 막장 안정성을 평가하였다. 본 연구의 분석 결과, 붕괴한 두 터널 현장의 결과와 평가 결과가 잘 일치하였으며, 대상터널의 지반 특성을 고려한 종합적인 평가 방법인 막장 안정성 평가 다이어그램에 의한 방법은 터널 설계 단계에서 터널의 막장 안정성을 확보하는 데 중요한 역할을 할 것으로 판단된다.

• The Korean Journal of Physiology
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• 제5권2호
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• pp.63-70
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• 1971

In an attempt to understand the possible effects of temperature and X-irradiation on the activities of surfactant in rabbits, the pulmonary surfactant from the rabbit was subjected to the incubation at $37^{\circ}C$ and X-irradiation with 900r in vitro, and activities of surfactant were measured at 10, 30, 60, and 90 minutes. Tension-area diagram of the lung extract was recorded automatically by the modified Langmuir-wilhelmy balance with a synchronized recording system designed in this Department. A comparison was made with the normal and the following results were obtained. 1) The maximal surface tension, minimal surface tension, width of the tension area diagram at the surface area of 40% and stability index of the normal rabbit lung extract were $31.6{\pm}3.11\;dynes/cm,\;8.2{\pm}0.56\;dynes/cm,\;21.4{\pm}4.40\;dynes/cm\;and\;1.12{\pm}0.22$,respectively. 2) In the $37^{\circ}C$ incubation group, maximal surface tension was similar to the normal value, while minimal surface tension was significantly lower and stability infer was markedly higher than the normal. 3) In the group where X-irradiation of 900r in vitro was applied, maximal surface tension did not differ greatly with the normal or the $37^{\circ}C$ incubation group. The minimal surface tension was significantly lower than the normal but comparing with the $37^{\circ}C$ incubation group, some decrease in minimal surface tension was noted. The width of the tension·area diagram at 40% and stability index in the irradiated group were significantly higher than the normal but a tendency of increase was noted comparing with the $37^{\circ}C$ incubation group.

• 대한화학회지
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• 제35권6호
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• pp.607-611
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• 1991

trans-$[Co(en)(tmd)Cl_2]^+$ 착이온의 수화반응에 대한 입체화학 생성물의 trans 이성질체와 cis이성질체의 비율을 분광광도법을 이용하여 온도를 변화시켜가면서 측정하였다. 이 실험 결과 cis-이성질체가 약 30% 이었으며, 중간체가 재배열됨을 알 수 있었다. 이 메카니즘을 좀 더 명확히 하기 위하여 EHT법을 이용하여 각 중간체의 Stability energy profile과 Interaction diagram 및 Orbital crrelation diagram를 계산하였다. 이 계산 결과 cis-이성질체의 생성경로가 실험결과와 거의 일치하였으며, Square Pyramid(SP)에서 약간 distortion된 상태에서 수화반응이 진행됨을 알 수 있었다

• 한국정밀공학회지
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• 제17권2호
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• pp.58-63
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• 2000

The dynamics of spindle-bearing-workpiece system significantly affects the cutting condition and stability in milling process. The present paper investigates the chatter stability of milling process due to the change in the dynamics of spindle-bearing-workpiece systems. In particular, the present paper focuses on chatter stability due to the presence of gyroscopic effect. An eigenvalue problem approach to the stability of milling process is extensively used in this paper. To incorporate the rotational speed dependent gyroscopic effect, an iterative algorithm is proposed. A numerical example is provided for examining the chatter stability problem in the presence of gyroscopic effects.

• 약학회지
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• 제35권5호
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• pp.372-378
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• 1991

To increase the stability and bioavailability of Omeprazole(OMP), which is used newly as a proton-pump inhibitor, inclusion complex of OMP with $\beta$-cyclodextrin($\beta$-CD) was prepared by coprecipitation method and its characteristics were ascertained by means of solubility test, DSC, IR, and the accelerated stability analysis. The type of OMP inclusion complex is classified as Bs-type on phase solubility diagram, and the stoichiometric ratio of OMP: $\beta$-CD complex is 1:2 and formation constant is 80.82/mole. The solubility of the complex could be increased remarkably by complexation compare with OMP. Degradation process of both OMP and OMP complex followed apparent first-order kinetics, of which degradation rate constants and activation energies are k$_{25}$=8.1$\times$10$^{-4}$/day, E$_{a}$=22 Kcal/mole (OMP), and k$_{25}$=4.65$\times$10$^{-6}$/day, E$_{a}$=35 Kcal/mole (complex), respectively. These results show the increase of the stability and solubility of OMP markedly, therefore it is believed that the improvement of stabilization for OMP by inclusion complexation might be practically available.

• 한국물환경학회지
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• 제29권2호
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• pp.176-183
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• 2013

The variation of the stable region of arsenic compounds in aqueous environment with temperature has been investigated by constructing the Pourbaix diagram of arsenic at different temperatures. The standard potential corresponding to the boundary between arsenic compounds with different charge valence was estimated to be decreased with temperature, which means the stability of arsenic compound with +5 charge valence increases. The distribution diagram of the most highly oxidized arsenic compound showed that arsenic acid is formed at higher pH and arsenate is generated at lower pH as temperature rises. The aquatic toxicity due to arsenic compounds was considered to be decreased with temperature in the neutral pH condition based on the $LD_T$ value defined in this study.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1285-1289
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• 2008

Increasing the flood control capacity's link that is enforcing to existing dam by unusual change of weather, While build planing construction by exiting spillway of tunnel type to dam, could know that part bed rock is formed as is different with design. Grasped topography of research area and geology state to definite distribution aspect of different bed rock, Place that achieved Surface geological Survey and correct Survey is difficult in some section enforced Electrical resistivity dipole-dipole investigation. Grasped stratigraphy distribution confirmation and fracture or weathering zone making out siding 2D-Resistivity Electrical resistivity diagram and Reverse analysis diagram, examining closely soil weathered rock rock's distribution state, established stability countermeasure plan