• Title/Summary/Keyword: critical response

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Quality Measurement of Rice - Mixture Extrudate by the Response Surface Regression Analysis (반응표면분석에 의한 쌀 압출성형물의 품질평가)

  • 고광진;김준평
    • Journal of the East Asian Society of Dietary Life
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    • v.1 no.3
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    • pp.305-311
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    • 1991
  • The study was designed to investigate overall acceptability of rice extrudate with added ginseng flour extruded by single screw extruder. Graphic three dimension analysis on response surface regression was conducted for overall acceptability evaluated by balanced incomplete block design. Overall acceptability, which formed a saddle point, increased as moisture content increased at lower die temperature, and as moisture content decreased at higher die temperature. Critical values of each variable which indicated optimum response are 5.0% ginseng content, 17.8% moisture content and 104.6$^{\circ}C$ die temperature, and optimum inferred score of overall acceptability is 59.6 and 90. Key words: extrdate, overall acceptability, response surface regression analysis, balanced incomplete block method.

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Effects of Intracerebroventricular Captopril on the Central Pressor Response to Bradykinin in Normotensive and Hypertensive Rats

  • Yeum, Cheol-Ho;Yoon, Pyung-Jin
    • The Korean Journal of Physiology
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    • v.28 no.2
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    • pp.191-196
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    • 1994
  • Captopril, an inhibitor of angiotensin converting enzyme, is also known to inhibit the degradation of bradykinin. We examined the effects of intracerebroventricular (ICV) captopril on the central pressor response to bradykinin in normotensive, 2-kidney, 1 clip Goldblatt (GHR) and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Captopril (1 mg) and bradykinin (5 nmol) were administered into the right lateral cerebral ventricle, and blood pressure and heart rate were continuously monitored throughout the experiment. ICV captopril alone did not affect the blood pressure within 10 minutes but it significantly augmented the central pressor response to bradykinin in GHR. On the contrary, captopril was without effect on the pressor response to bradykinin in normotensive and DOCA-salt rats. These findings indicate that endogenous kinins are not critical in regulating arterial pressure in normotensive and DOCA hypertensive rats. However, in GHR, an enhanced activity of the brain kallikrein-kinin system in maintaining the high blood pressure is suggested.

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Vibration Response Analysis of a Small Gas Turbine Rotor (소형 가스터빈 회전체의 진동응답 해석)

  • Kim, Young-Cheol;Ha, Jin-Woong;Myung, Ji-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.13 no.3
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    • pp.18-23
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    • 2010
  • This paper predicts the unbalance and transient (start-up) response of a 5MW industrial gas turbine by using commercial rotordynamic tool, DYNAMICS 4.3. The gas turbine is operated at 12,975rpm on squeeze film dampers or tilting pad bearings. The stiffness and damping coefficients of the squeeze film dampers and tilting pad bearings are estimated. It is seen that the vibration amplitude of the gas turbine rotor is sufficiently small around the critical speeds and at the rated speed.

Hybridal Analysis of High-Frequency Combustion Instability with Pressure-Coupled Combustion Response Model (압력섭동과 연관된 연소응답모델에 기초한 고주파 연소불안정의 이론-수치적 고찰)

  • 윤웅섭;이길용
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.05a
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    • pp.253-257
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    • 2003
  • Theoretical-numerical analysis of wave instability is conducted with parametric response function model. Fluctuating instantaneous mass evaporation rate functionally coupled with pressure perturbations with phase lag is assumed to examine the validity of the method. With sufficiently large amplitude and less phase lag to perturbation, combustion response is resonant to pressure waves, unstable waves are amplified, and the system is driven to instability. Magnitude of response is a crucial instability parameter in the determination of a stability margins and makes a critical change of balancing conditions between the amplifying and damping acoustic energies. In the phase regime the unstable waves are amplified, whereas, the acoustic waves are attenuated in the out-of-phase regime. In the intermediate regime, no distinct tendency of unstable waves was determined.

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Effects of deck's width-to-depth ratios and turbulent flows on the aerodynamic behaviors of long-span bridges

  • Lin, Yuh-Yi;Cheng, Chii-Ming;Lan, Chao-Yuan
    • Wind and Structures
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    • v.6 no.4
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    • pp.263-278
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    • 2003
  • This study investigates the effects of a bridge deck's width-to-depth (B/H) ratio and turbulence on buffeting response and flutter critical wind speed of long-span bridges by conducting section model tests. A streamlined box section and a plate girder section, each with four B/H ratios, were tested in smooth and turbulent flows. The results show that for the box girders, the response increases with the B/H ratio, especially in the vertical direction. For the plate girders, the vertical response also increases with the B/H ratio. However, the torsional response decreases as the B/H ratio increases. Increasing the B/H ratio and intensity of turbulence tends to improve the bridge's aerodynamic stability. Experimental results obtained from the section model tests agree reasonably with the calculated results obtained from a numerical analysis.

Comparison Study on Mode and Response Localizations (모드 국부화와 응답 국부화의 비교연구)

  • 하동진;유홍희
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.6
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    • pp.478-485
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    • 2004
  • Vibration localization characteristics of mistuned repeated structures are investigated. The mistuning often creates significant response discrepancies among subcomponents of a repeated structure. As the result of the discrepancies, critical fatigue often occurs in a repeated structure. Therefore, it is of great importance to predict the vibration response of the mistuned repeated structures accurately. In this paper, a simplified model is employed and dimensionless parameters that influence the localization characteristics are identified. Through parameter study, two localization phenomena are investigated and compared.

Vibration Localization of a Periodic Structure Undertaking External Force (외력을 받는 주기적 구조물의 진동 국부화)

  • Kim, Jae-Young;Yoo, Hong-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.543-548
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    • 2000
  • Vibration localization of a periodic structure with mistuning is presented in this paper. Mistuning in periodic structures can lead to an increase of the forced response which is much larger than those of perfectly tuned assembly. Thus, mistuning has a critical impact on high cycle fatigue in structures, and it is of great importance to predict the mistuned forced response in efficient manner. In this paper, forced response of a coupled pendulum is investigated to identify localization effects of periodic structures. The effects of mistuning and damping on the maximum forced response are examined. It is seen that in certain condition of mistuning and coupling, strong localization occurs and this can be significant under weak damping.

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Implementation Issues to Quick Response System in Korean Fashion Industry (국내 패션산업의 Quick Response System 추진 현황과 문제점)

  • 신상무
    • The Journal of Society for e-Business Studies
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    • v.3 no.1
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    • pp.175-194
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    • 1998
  • The purpose of this study is to examine the current status of Quick Response adoption, and to recognize the implementation problems of QR system in the Korean fashion industry. We reviewed the theoretical background of QR system, analyzed the current status of QR adoption, and identified critical issues to implement the system in our fashion business environment. Previous literatures and information gained from communication service organizations were used for this study The major problems recognized are lack of inter-organizational information network, closed supply channels, non-standardization of QR implementation, and low level of information technology usage including KAN, POS, and EDI. Strong mutual partnership between streams for shared common goals and clear QR mind setting of top management with commitment to information sharing are considered needed for the successful adoption of QR system in domestic fashion industry.

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Demand Response of Large-Scale General and Industrial Customer using In-House Pricing Model (사내요금제를 활용한 대규모 수용가 수요반응에 관한 연구)

  • Kim, Min-Jeong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.7
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    • pp.1128-1134
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    • 2016
  • Demand response provides customer load reductions based on high market prices or system reliability conditions. One type of demand response, price-based program, induces customers to respond to changes in product rates. However, there are large-scale general and industrial customers that have difficulty changing their energy consumption patterns, even with rate changes, due to their electricity demands being commercial and industrial. This study proposes an in-house pricing model for large-scale general and industrial customers, particularly those with multiple business facilities, for self-regulating demand-side management and cost reduction. The in-house pricing model charges higher rates to customers with lower load factors by employing peak to off-peak ratios in order to reduce maximum demand at each facility. The proposed scheme has been applied to real world and its benefits are demonstrated through an example.

Seismic energy dissipation in torsionally responding building systems

  • Correnza, J.C.;Hutchinson, G.L.;Chandler, A.M.
    • Structural Engineering and Mechanics
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    • v.3 no.3
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    • pp.255-272
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    • 1995
  • The paper considers aspects of the energy dissipation response of selected realistic forms of torsionally balanced and torsionally unbalanced building systems, responding to an ensemble of strong-motion earthquake records. Focus is placed on the proportion of the input seismic energy which is dissipated hysteretically, and the distribution of this energy amongst the various lateral load-resisting structural elements. Systems considered comprise those in which torsional effects are discounted in the design, and systems designed for torsion by typical code-defined procedures as incorporated in the New Zealand seismic standard. It is concluded that torsional response has a fundamentally significant influence on the energy dissipation demand of the critical edge elements, and that therefore the allocation of appropriate levels of yielding strength to these elements is a paramount design consideration. Finally, it is suggested that energy-based response parameters be developed in order to assist evaluations of the effectiveness of code torsional provisions in controlling damage to key structural elements in severe earthquakes.