• Title/Summary/Keyword: RSM

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The Sensitivity Analysis of Derailment in Suspension Elements of Rail Vehicle (철도차량 현수장치의 탈선에 대한 민감도 연구)

  • 심태웅;박찬경;김기환
    • Proceedings of the KSR Conference
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    • 1999.11a
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    • pp.566-573
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    • 1999
  • This paper is the result of sensitivity analysis of derailment with respect to the selected suspension elements for the rail vehicle. Derailment phenominon has been explained by the derailment quotient. Thus, the sensitivity of derailment is suggested by a response surface model(RSM) which is a functional relationship between derailment quotient and characteristics of suspension elements. To summarize generation of RSM, we can introduce the procedure of sensitivity analysis as follows. First, to form a RSM, a experiment is performed by a dynamic analysis code, VAMPIRE according to a kind of the design of experiments(DOE). Second, RSM is constructed to a 1$\^$st/ order polynomial and then main effect fators are screened through the stepwise regression. Finally, we can see the sensitivity level through the RSM which only consists of the main effect factors and is expressed by the liner, interaction and quadratic effect terms.

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Decomposable polynomial response surface method and its adaptive order revision around most probable point

  • Zhang, Wentong;Xiao, Yiqing
    • Structural Engineering and Mechanics
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    • v.76 no.6
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    • pp.675-685
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    • 2020
  • As the classical response surface method (RSM), the polynomial RSM is so easy-to-apply that it is widely used in reliability analysis. However, the trade-off of accuracy and efficiency is still a challenge and the "curse of dimension" usually confines RSM to low dimension systems. In this paper, based on the univariate decomposition, the polynomial RSM is executed in a new mode, called as DPRSM. The general form of DPRSM is given and its implementation is designed referring to the classical RSM firstly. Then, in order to balance the accuracy and efficiency of DPRSM, its adaptive order revision around the most probable point (MPP) is proposed by introducing the univariate polynomial order analysis, noted as RDPRSM, which can analyze the exact nonlinearity of the limit state surface in the region around MPP. For testing the proposed techniques, several numerical examples are studied in detail, and the results indicate that DPRSM with low order can obtain similar results to the classical RSM, DPRSM with high order can obtain more precision with a large efficiency loss; RDPRSM can perform a good balance between accuracy and efficiency and preserve the good robustness property meanwhile, especially for those problems with high nonlinearity and complex problems; the proposed methods can also give a good performance in the high-dimensional cases.

Preparation of Coconut Oil in Water Emulsions Using Tween-Span Type Mixed Surfactant : Optimization of CCD-RSM (Tween-Span계 혼합계면활성제를 이용한 Coconut Oil 원료 O/W 유화액의 제조 : CCD-RSM을 이용한 최적화)

  • Yoo, Bong-Ho;Zhu, Kaiyang;Zuo, Chengliang;Lee, Seung Bum
    • Applied Chemistry for Engineering
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    • v.31 no.1
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    • pp.19-24
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    • 2020
  • In this study, the O/W emulsions prepared from coconut oil and the non-ionic mixed surfactant as Tween-Span system were evaluated and optimized in order to upgrade the stability of manufactured emulsions. For the optimization, a central composite design model-response surface methodology, so called as CCD-RSM was implemented. Quantitative factors were the hydrophile-lipophilie balance (HLB), amount of non-ionic mixed surfactant and emulsification speed while experimental results included the mean droplet size (MDS), emulsion stability index (ESI), and thermal instability index (TII). Optimized values of the HLB, amount of non-ionic mixed surfactant and emulsification speed obtained from CCD-RSM were 9.1, 8.7 wt.%, and 6,200.8 rpm, respectively. Expected experimental results for MDS, ESI, and TII under the optimized experimental condition were 151.0 nm, 99.86, and 3.17%, respectively. The average error from actual experiments which established for validation of the conclusions was lower than 3.5%. Therefore, a highly favorable level could be obtained when the optimized CCD-RSM was applied to manufacturing the O/W emulsion in this study.

Investigation of the Prediction Performance of Turbulence and Combustion Models for the Turbulent Partially-premixed Jet Flame (난류 부분예혼합 제트화염에 대한 난류 및 연소모델의 예측성능 검토)

  • Kim, Yu Jeong;Oh, Chang Bo
    • Fire Science and Engineering
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    • v.28 no.4
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    • pp.35-43
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    • 2014
  • The prediction performance of 9 model sets, which combine 3 turbulent models and 3 combustion models, was investigated numerically for turbulent partially-premixed jet flame. The standard ${\kappa}-{\varepsilon}$ (SKE), Realizable ${\kappa}-{\varepsilon}$ (RKE) and Reynolds stress model (RSM) were used as a turbulence model, and the eddy dissipation concept (EDC), steady laminar flamelet (SLF) and unsteady laminar flamelet model (ULF) were also adopted as a combustion model. The prediction performance of those 9 model sets was evaluated quantitatively and qualitatively for Sandia D flame of which flame structure was measured precisely. The flame length was predicted as, from longest to shortest, RSM > SKE > RKE, and the RKE predicted the flame length of the jet flame much shorter than experiment. The flame temperature was over predicted by the combination of RSM + SLF or RSM + ULF while the flame length obtained by RSM + SLF and RSM + ULF was well agreed with the experiment. The combination of SKE + SLF and SKE + ULF predicts well the flame length as well as the temperature distribution. The SKE turbulence model was most superior to the other turbulent models, and SKE + ULF showed the best prediction performance for the structure of turbulent partially-premixed jet flame.

Effects of substitution of soybean meal with rapeseed meal and glutamine supplementation on growth performance, intestinal morphology, and intestinal mucosa barrier of Qiandongnan Xiaoxiang Chicken

  • Zhang, Bolin;Liu, Ning;Hao, Meilin;Xie, Yuxiao;Song, Peiyong
    • Animal Bioscience
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    • v.35 no.11
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    • pp.1711-1724
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    • 2022
  • Objective: The present study was to evaluate the effects of different rapeseed meal substitution (RSM) and glutamine (Gln) supplementation on growth performance, intestine morphology, and intestinal mucosa barrier of broilers. Methods: Four hundred and twenty Qiandongnan Xiaoxiang Chicken at 1 day of age with similar weight were chosen and were randomly assigned into 7 groups, consisting of 10 replicates per group and 6 broilers per replicate. Three groups were provided with diets separately containing 0%, 10%, and 20% RSM, and the other four groups were fed with diets separately supplemented with 0.5% and 1% Gln based on the inclusion of 10% and 20% RSM. At 21 and 42 days of age, 10 broilers per group were chosen to collect plasma and intestinal samples for further analysis. Results: The results showed that 10% RSM decreased average daily feed intake (ADFI) and average daily weight gain (ADG) of broilers at 21 days of age (p<0.05). Furthermore, both ADFI and ADG of broilers at 21 and 42 days of age were decreased by 20% RSM, while feed conversion ratio (FCR) was increased (p<0.05). Besides, 10% RSM resulted in lower intestinal villus height and the ratio of villus height to crypt depth, deeper crypt depth (p<0.05), combined with the lower mRNA expressions of occludin, claudin-1, and zonula occludens-1 (ZO-1) in broilers at 21 days of age (p<0.05). Similar results were also observed in broilers at 21 and 42 days of age fed with 20% RSM. However, 1% Gln improved the growth performance of broilers fed with 10% and 20% RSM (p<0.05), ameliorated intestine morphology and elevated mRNA expressions of occludin, claudin-1 and ZO-1 (p<0.05). Conclusion: In conclusion, the increasing inclusion of RSM resulted in more serious effects on broilers, however, 1.0% Gln could reverse the negative effects induced by the inclusion of RSM.

Reliability Based Design Optimization using Moving Least Squares (이동최소자승법을 이용한 신뢰성 최적설계)

  • Park, Jang-Won;Lee, Oh-Young;Im, Jong-Bin;Lee, Soo-Yong;Park, Jung-Sun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.5
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    • pp.438-447
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    • 2008
  • This study is focused on reliability based design optimization (RBDO) using moving least squares. A response surface is used to derive a limit-state equation for reliability based design optimization. Response surface method (RSM) with least square method (LSM) or Kriging will be used as a response surface. RSM is fast to make the response surface. On the other hand, RSM has disadvantage to make the response surface of nonlinear equation. Kriging can make the response surface in nonlinear equation precisely but needs considerable amount of computations. The moving least square method (MLSM) is made of both methods (RSM with LSM+Kriging). Numerical results by MLSM are compared with those by LMS in Rosenbrock function and six-hump carmel back function. The RBDO of engine duct of smart UAV is pursued in this paper. It is proved that RBDO is useful tool for aerospace structural optimal design problems.

Isolation and Identification of Rice Root Endophytic Antagonistic Serratia marcescens (벼 뿌리 내생 항균성 Serratia marcescens의 분리 및 동정)

  • Lee, Sook-Kyung;Song, Wan-Yeob;Kim, Hyung-Moo
    • Research in Plant Disease
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    • v.10 no.1
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    • pp.63-68
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    • 2004
  • Twenty-three strains of Serratia sp., isolated from surface-sterilized rice roots collected in Chonbuk and Chungnam province, were identified and characterized. They were Gram-negative, rod shaped and red pigmented typically and their endophytism was confirmed by inoculation and reisolation of the strains in planta. Their antifungal activity against 4 rice pathogenic fungi was compared and ranged from 62.4 to 85.2% against Rhizoctonia solani and 68.0 to 88.5% against Pyricularia grisea. Among the 23 strains tested, strain Rsm220 showed the strongest inhibition activity against 4 pathogenic fungi. The strain was, therefore, selected as a biocontrol candidate for both the pathogens and its bacteriological characteristics and 165 rDNA sequences were analyzed. Phenotypic and biochemical characteristics of the selected Rsm220 were highly related to the type strain of S. marcescens and 165 rDNA sequencing of Rsm220 showed a homology of 98.2% to the type strain of S. marcescens. The strain Rsm220 was identified as S. marcescens and the inhibition result of this endophytic strain indicates that it is a potential biocontrol agent for R. solani and R grisea.

Comparing with self-efficacy and knowledge, attitudes about radiation safety management of dental hygienists and students at department of dental hygiene (치과위생사와 치위생과 학생의 자기효능감과 방사선안전관리 지식 및 태도에 대한 비교)

  • Yoon, Jung-Ae;Yoon, Young-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.11 no.5
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    • pp.729-739
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    • 2011
  • Objectives : It is important to catch individual characteristics by measuring the level of self-efficacy, radiation safety knowledge, attitudes to increase behavior levels in the radiation safety management(RSM) and we consider this should be applied to the professional program development to improve RSM activities of dental hygienist and students at department of dental hygiene. Methods : This study mentioned mainly self-efficacy, radiation safety knowledge, attitudes for dental hygienists and the second & third year students at department of dental hygiene in Pusan area to provide the correct information associated with the use of radiation and to be aid in the development program to increase behavior levels in the RSM in dental care institutions and schools in the future and performed a survey 8 May to 7 Juiy, 2011. The survey results were as follows Results : 1. The results of self-efficacy is $3.53{\pm}0.42$ points for the dental hygienist and $3.32{\pm}0.40$ points for students(p<0.001). 2. According to the knowledge level of RSM, the result is $11.7{\pm}3.12$ points for the dental hygienist and $9.56{\pm}2.72$ points for students(p<0.001). 3. According to the knowledge level of RSM, the result is $4.40{\pm}0.49$ points for the dental hygienist and $4.22{\pm}0.56$ points for students(p<0.001). 4. According to relationship among self-efficacy, radiation safety knowledge and attitudes, the higher the score for knowledge of RSM was, the higher the score for self-efficacy was. The higher the score for attitudes was, the higher the score for self-efficacy and knowledge was(p<0.01). 5. The factors to affect attitudes about RSM were self-efficacy, knowledge(p<0.01).

Apparent Ileal Digestibility of Nutrient in Plant Protein Feedstuffs for Finishing Pigs

  • Han, Y.K.;Kim, I.H.;Hong, J.W.;Kwon, O.S.;Lee, S.H.;Kim, J.H.;Min, B.J.;Lee, W.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1020-1024
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    • 2003
  • Five barrows (average initial body weight 58.6 kg) were used to determine the apparent ileal digestibilities of amino acids, DM, N and energy in various soybean meal, rapeseed meal and coconut meal in finishing pigs. Dietary treatments included 1) KSBM (Korean soybean meal), 2) CSBM (Chinese soybean meal), 3) ASBM (Argentine soybean meal), 4) RSM (Rapeseed meal), and 5) CNM (Coconut meal). The diets were corn starch-based and formulated so that each protein source provided the same amount of total ME (3,490 kcal/kg), CP (15.70%), lysine (1.00%), Ca (0.80%) and P (0.60%). Protein content of the KSBM was higher than the CSBM and ASBM, with all values similar to those expected, and protein content of the CNM was lower than that of the SBM preparation and RSM. Apparent ileal digestibilities of histidine, lysine, threonine, alanine, asparatic acid, cystine, glutamic acid and serine were greater for the KSBM, CSBM, ASBM and RSM than for the CNM (p<0.05). Also, the apparent ileal digestibilities of methionine, leucine, phenylalanine, valine and tyrosine were greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05). Overall, the apparent ileal digestibilities of total essential amino acids were greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05), and the apparent ileal digestibilities of total non essential amino acids were greater for the KSBM, CSBM, ASBM and RSM than for the CNM (p<0.05). No difference (p>0.05) in apparent digestibility of DM at the small intestine was observed among the treatments. However, the apparent digestibility of DM at the total tract was greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05). Also, apparent digestibilities of N and digestible energy at the small intestine and total tract were greater for the KSBM than for the RSM and CNM (p<0.05). In conclusion, nutrient digestibility values of SBM preparations and RSM were relatively high compared to CNM.