• Title/Summary/Keyword: Relative performance evaluation

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Performance Evaluation of Cascade Considering Fluid/Structure Coupling Deformation (유체/구조 연계 변형효과를 고려한 케스케이드의 성능평가)

  • Oh, Se-Won;Kim, Dong-Hyun;Kim, Yu-Sung;Park, Oung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.275-282
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    • 2007
  • In this study, a fluid-structure interaction (FSI) analysis system has been developed in order to evaluate the turbine cascade performance with blade structural deformation effect. Relative movement of the rotor with respect to stator is reflected by modeling independent two computational domains. To consider the deformed position of rotor airfoil, dynamic moving grid method is applied. Reynolds-averaged Navier-Stokes equations with one equation Spalart-Allmaras and two-equation SST $k-{\varepsilon}$ turbulence models are solved to predict unsteady fluid dynamic loads. A fully implicit time marching scheme based on the Newmark direct integration method with high artificial damping is used to compute the fluid-structure interaction problem. Cascade performance evaluations for different elastic axis positions are presented and compared each other. It is importantly shown that the predicted aerodynamic performance considering structural deformation effect of blade can show some deviations compared to the data generally computed from rigid blade configurations and the position of elastic axis also tend to give sensitive effect.

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Seismic reliability evaluation of steel-timber hybrid shear wall systems

  • Li, Zheng;He, Minjuan;Lam, Frank;Zhou, Ruirui;Li, Minghao
    • Earthquakes and Structures
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    • v.13 no.3
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    • pp.289-297
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    • 2017
  • This paper presents seismic performance and reliability evaluation on steel-timber hybrid shear wall systems composed of steel moment resisting frames and infill light frame wood shear walls. Based on experimental observations, damage assessment was conducted to determine the appropriate damage-related performance objectives for the hybrid shear wall systems. Incremental time-history dynamic analyses were conducted to establish a database of seismic responses for the hybrid systems with various structural configurations. The associated reliability indices and failure probabilities were calculated by two reliability methods (i.e., fragility analysis and response surface method). Both methods yielded similar estimations of failure probabilities. This study indicated the greatly improved seismic performance of the steel-timber hybrid shear wall systems with stronger infill wood shear walls. From a probabilistic perspective, the presented results give some insights on quantifying the seismic performance of the hybrid system under different seismic hazard levels. The reliability-based approaches also serve as efficient tools to assess the performance-based seismic design methodology and calibration of relative code provisions for the proposed steel-timber hybrid shear wall systems.

Air Similarity Test for the Evaluation of Aerodynamic Performance of Steam Turbine (스팀터빈의 공력성능 평가를 위한 공기 상사실험)

  • Lim, Byeung-Jun;Lee, Eun-Seok;Yang, Soo-Seok;Lee, Ik-Hyoung;Kim, Young-Sang;Kwon, Gee-Bum
    • The KSFM Journal of Fluid Machinery
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    • v.7 no.5 s.26
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    • pp.29-35
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    • 2004
  • The turbine efficiency is an important factor in power plant, and accurate evaluation of steam turbine performance is the key issue in turbo machinery industry. The difficulty of evaluating the steam turbine performance due to its high steam temperature and pressure environment makes the most steam turbine tests to be replaced by air similarity test. This paper presents how to decide the similarity conditions of the steam turbine test and describes its limitations and assumptions. The test facility was developed and arranged to conduct an air similarity turbine performance test with various inlet pressure, temperature and mass flow rate. The eddy-current type dynamometer measures the turbine-generated shaft power and controls the rotating speed. Pressure ratio of turbine can be controled by back pressure control valve. To verify its test results, uncertainty analysis was performed and relative uncertainty of turbine efficiency was obtained.

Evaluation of the Performance on WindPRO Prediction (WindPRO의 예측성능 평가)

  • O, Hyeon-Seok;Go, Gyeong-Nam;Heo, Jong-Cheol
    • 한국태양에너지학회:학술대회논문집
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    • 2008.11a
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    • pp.300-305
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    • 2008
  • Using WindPRO that was software for windfarm design developed by EMD from Denmark, wind resources for the western Jeju island were analyzed, and the performance of WindPRO prediction was evaluated in detail. The Hansu site and the Yongdang site that were located in coastal region were selected, and wind data for one year at the two sites were analyzed using WindPRO. As a result, the relative error of the Prediction for annual energy Production and capacity factor was about ${\pm}20%$. For evaluating wind energy more accurately, it is necessary to obtain lots of wind data and real electric power production data from real windfarm.

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A Study on Design of S-BSC(Safety-Balanced ScoreCard) for Total Safety Evaluation (종합 안전평가를 위한 S-BSC(Safety-Balanced ScoreCard) 설계에 관한 연구)

  • Yang, Kwang-Mo
    • Journal of the Korea Safety Management & Science
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    • v.10 no.3
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    • pp.1-8
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    • 2008
  • Risk is the probability of an adverse event given exposure to hazard. There are many reason for unsafety situation without safety operation. The reason is no safety evaluation system in small enterprise. And then this study purposes safety management activities that is evaluation system for total safety efficiency's maximization. Therefore, in this study, this model that can evaluate quantitative activities in small enterprise that maximize safety efficiency wishes to do design using balanced scorecard. In other words, this study aims to suggest a performance measurement model reflecting the characteristics of safety evaluation system, especially the model for return manufacturing related to safety, and to develop the S-BSC(Safety-Balanced ScoreCard) measurement model using a weight lifetime value to which a relative weight is applied by using AHP based on the BSC.

Damage Evaluation of a Simply Supported Steel Beam Using Measured Acceleration and Strain Data (가속도 및 변형률 계측데이터를 이용한 철골 단순보 손상평가)

  • Park Soo-Yong;Park Hyo-Seon;Lee Hong-Min;Choi Sang-Hyun
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.167-174
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    • 2006
  • In this paper, the applicability of strain data to a strain-energy-based damage evaluation methodology in detecting damage in a beam-like structure is demonstrated. For the purpose of this study, one of the premier damage evaluation methodology based on modal amplitudes, the damage index method, is expanded to accomodate strain data, and the numerical and experimental verifications are conducted using numerical and experimental data. To compare the relative performance of damage detection, the damage evaluation using acceleration data is also performed for the same damage scenarios. The experimental strain and acceleration data are extracted from laboratory static and dynamic tests. The numerical and experimental studies show that the strain data as well as acceleration data can be utilized in detecting damage.

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Classification of usability elements for the evaluation of the user interface of consumer electronic products (전자제품 휴먼 인터페이스 평가를 위한 사용편의성 요소의 체계적 분류)

  • 한수미;윤명환;한성호;곽지영;홍상우;박경수
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.372-375
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    • 1997
  • Classivication scheme of usability element for the evaluation of consumer electronic product was developed in this study. Using hierachical structuring and clustering methods, usability element of consumer products interface is developed both for the performance perspective and for the image/appeal perspective of a product. Perfoormance element included variables such as simplicity, directness, learn- ability, flexibility, user support and effectiveness. Image/Appeal element included variables such as sensibility, descriptive impression, evaluation of appeal, and attitude towards the product. The classifi- cation scheme developed in this study is found to be comprehensive and robust relative to other existing paradigms. They can be effectively used and applied for the usability evaluation of consumer electronic products.

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Studies on the Manifestation of Hybrid vigour and Combining Ability in Polyvoltine X Bivoltine (cross breed) Hybrids of Mulberry Silkworm Bombyx mori L.

  • Seshagiri, S.V.;Naik, S. Sankar;Seetharamulu, J.;Goel, A.K.;Raju, P.J.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.24 no.1
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    • pp.7-16
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    • 2012
  • To meet the local requirement i.e. the tropical stress of Andhra Pradesh and marginal farmers, twenty four new hybrid combinations were tested in Line x Tester method involving eight newly developed polyvoltine oval lines viz., MSO1, MSO2, MSO3, MSO4, MSO5, MSO6, MSO7 and MSO8 and three bivoltine silkworm breeds viz., APS12, APS45 and APS8 as testers. These hybrids were reared to evaluate their performance. Data for eight economically important metric traits viz., fecundity, cocoon yield per 10,000 larvae by number, cocoon yield per 10,000 larvae by weight, survival rate, cocoon weight, cocoon shell weight, cocoon shell ratio and filament length was recorded. General combining ability (gca), specific combining ability (sca) and heterosis were analyzed. Further, the relative merit of the hybrids for all the traits under study was also assessed adopting Evaluation Index method. Based on combining ability effects, heterosis and evaluation index, five hybrid combinations viz., MSO3 $\times$ APS45, MSO1 $\times$ APS12, MSO7 $\times$ APS8, MSO2 $\times$ APS45 and MSO1 $\times$ APS45 were selected for further evaluation in different seasons.

Development of advanced rigorous two-step code system for evaluation of radioactive waste with high-resolution activation calculation

  • Kim, Do Hyun;Kim, Jiseok;Lee, Han Rim;Sun, Gwang Min;Shin, Chang Ho;Kim, Jong Kyung
    • Nuclear Engineering and Technology
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    • v.53 no.6
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    • pp.2011-2018
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    • 2021
  • Nowadays, evaluation of amounts and distributions of radioactive waste is an important preparatory step in the process of nuclear reactor decommissioning. For tentative estimation of radioactive waste, a cell-based rigorous 2 step (R2S) method usually is used; however, a poor resolution caused by the averaged flux and spectrum in a cell is still a great challenge because of leading to underestimated or overestimated results. To overcome the poor resolution, several systems were introduced. Neither system, however, provides any function for evaluation of radioactive waste amount and distribution. Thus, it is additionally required to classify radioactive waste based on the results of activation calculation. In this study, the advanced R2S (AR2S) system was developed. To verify the performance of the system, its results for a verification problem were compared with those of the cell-based R2S method. The results showed good agreement, which is to say, within 2.0% relative error. Also, several characteristics of fine/coarse mesh were analyzed. To demonstrate the performance of the AR2S system, the radioactive waste from the Japan Power Demonstration Reactor (JPDR) was estimated, and the result indicated a high-resolution distribution. Therefore, it is expected that the AR2S system will prove useful for precise evaluation of radioactive waste.

A Study on Residents' Subjective Evaluation of the Elderly Housing Environment in the Suburbs of Chiba City, Japan (고령자거주요소에 대한 거주자의 주관적 평가연구 - 일본치바시근교의 유료노인시설을 대상으로 -)

  • CheHuiJohn
    • Journal of the Korean housing association
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    • v.7 no.2
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    • pp.139-151
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    • 1996
  • The Purpose of this study is to examine residents' subjective satisfaction of the elderly housing environment and to suggest some major factors which can be used as basic design guidelines for the elderly housing. as the number of the elderly is growing in Japan For this purpose. data were collected through a questionnaire survey method, Some questions on their hope for the conditions of the elderly housing were asked to 265 old People living in the suburbs of Chiba city. Japan. Based on the findings of the statistical factor analysis, the major factors which affected on the elderly housing environment of the study can be summarized as follows ;(1)Factor1 is correlated with the space design element represented by the elderly dwelling performance and overall efficiency for the dwelling exterior space design (2)Factor2 is relative to the interior environmental element with Physiological and sensitive performance for borne services system. (3)Factor3 can be explained the moving and communication performance for Physical uneasiness of outdoor activities and request of public cultural spaces. (4)Factor4 is relative to the mental rest element with safety accidents for moving activities etc. and psychological isolation for the elderly.

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