• 제목/요약/키워드: condition number

검색결과 5,592건 처리시간 0.035초

고유구조를 이용한 다중출력 시스템의 강인한 관측기 설계 (Robust Observer Design for Multi-Output Systems using Eigenstructure)

  • 허건수;남준철
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2003년도 춘계학술대회 논문집
    • /
    • pp.39-44
    • /
    • 2003
  • It was shown that the robustness of deterministic observers with respect to modeling errors, measurement bias and round-off errors can be represented by a single performance index the condition number of the observer eigenvector matrix. In this paper, a robust observer for multi-output systems is designed using the left eigenstructure assignment, where the observer gain can not be determined uniquely with respect to the desired observer poles. Utilizing the eigenstructuer assignment for the robustness of the observer, the desired eigenvector matrix is selected to achieve the observer eigenvector matrix with the small condition number. The performance of the designed robust observer is evaluated in a spindle-drive simulation example where the load speed to be estimated based on the measured signals.

  • PDF

Procedure for improving dynamic operability of chemical processes

  • Kwon, Youngwoon;Chang, Tae-Suk;Yoon, En-Sup
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
    • /
    • pp.332-335
    • /
    • 1995
  • A simple and effective method for improving Euclidean norm condition number for chemical processing system is presented. The singular value sensitivities of Freudenberg et al. (1982) is used to estimate the behavior of singular values of process transfer function matrix when design parameter is changed, then the condition number can be calculated straightforwardly. The method requires explicit dependencies of each transfer function matrix elements on design parameters. These dependencies can be obtained either by symbolic differentiation in the form of explicit function of design parameters, or by numerical perturbation studies for units with large and complicated models. Gerschgorin-type lower bound for minimum singular value is introduced to detect the large divergencies near singular point due to linearity of sensitivities. The case studies are performed to show the efficiency of the proposed method.

  • PDF

고해상도 수치기법의 경계조건에 따른 공력음향 특성에 관한 연구 (THE STUDY OF AERO-ACOUSTICS CHARACTERISTICS BY THE BOUNDARY CONDITIONS OF HIGH ORDER SCHEME)

  • 이상수;김재수
    • 한국전산유체공학회지
    • /
    • 제14권3호
    • /
    • pp.25-32
    • /
    • 2009
  • The present paper focuses on the analysis of aero-acoustics characteristic by appling different four boundary conditions. The high-order and high-resolution numerical schemes are used for discrete accurate computation of compressible flow. The four boundary conditions include extrapolation, characteristic boundary condition, zonal characteristic boundary condition. These boundary conditions are applied to the computation of two dimensional circular cylinder flows with Mach number of 0.3 and Reynolds number of 400. The computation results are validated against measurement data and other computation results for the Strouhal frequency of vortex shedding, the mean drag coefficient and root-mean-square lift for the unsteady periodic flow regime. The characteristics of secondary frequency is predicted by three kinds of boundary conditions.

Stability of LTI Systems with Unstructured Uncertainty Using Quadratic Disc Criterion

  • Yeom, Dong-Hae;Park, Jin-Bae;Joo, Young-Hoon
    • Journal of Electrical Engineering and Technology
    • /
    • 제7권1호
    • /
    • pp.124-131
    • /
    • 2012
  • This paper deals with robust stability of linear time-invariant (LTI) systems with unstructured uncertainties. A new relation between uncertainties and system poles perturbed by the uncertainties is derived from a graphical analysis. A stability criterion for LTI systems with uncertainties is proposed based on this result. The migration range of the poles in the proposed criterion is represented as the bound of uncertainties, the condition number of a system matrix, and the disc containing the poles of a given nominal system. Unlike the existing methods depending on the solutions of algebraic matrix equations, the proposed criterion provides a simpler way which does not involves algebraic matrix equations, and a more flexible root clustering approach by means of adjusting the center and the radius of the disc as well as the condition number.

안개에 기인하는 배추(Brassica pekinensis)의 잡초경합(雜草競合) 및 제초제반응(除草劑反應) 특이성(特異性) (Specifics in Weed Competition and Herbicide Response of Chinese Cabbage(Brassica pekinensis) under Foggy Condition)

  • 구자옥;박태동;천상욱;국용인
    • 한국잡초학회지
    • /
    • 제15권4호
    • /
    • pp.270-277
    • /
    • 1995
  • 본 연구는 안개제조 장치가 설치된(Auto foggy system: SAE KI RTN Co.) 온실내 tray 시험으로 수행되었으며 시험결과를 요약하면 다음과 같다. 1. 안개조건하에서 배추의 엽수와 지상부 생체중에는 차이가 없었으나, 초장은 더 증가하였다. 2. 안개조건하에서 40일과 60일 경합처리로 초장이 감소되었으나 엽수에서는 차이가 없었다. 그리고 지상부 생체중은 전 경합기간의 안개조건하에서 감소하였고 특히, 40일(日) 경합구에서 감소정도가 큰 경향이었다. 3. Pendimethalin과 Napropamide 처리로 지상부 생체중은 안개조건하에서 감소하였고, 엽수는 Pendimethalin 처리에서만 이식후 60일에 감소하였다. 4. Pendimethalin, Napropamide 및 Alachlor 처리에서는 안개와 비안개간에 방제효과상의 차이가 없었고 Trifluralin에서는 처리일수가 경과함에 따라 바랭이 유묘출현하게 되므로써 안개조건하에서 방제효과가 낮아지는 경향이 있었다.

  • PDF

강우의 시간분포를 고려한 CN값 산정 (SCS Curve Number and temporal Variation of Rainfall)

  • 조홍제;이태영
    • 한국수자원학회논문집
    • /
    • 제36권2호
    • /
    • pp.183-193
    • /
    • 2003
  • 강우의 지속시간을 처리하는 방법에 따라 AMC조건과 강우의 시간분포인(1차, 2차, 3차, 4차 모멘트)가 유출에 미치는 연관성을 연구하였다. 연구결과 강우를 10분위로 고려하는 경우, CN은 AMCIII조건에서 1차 및 2차 모멘트와 상관성을 보였으나 그 외의 조건에서는 상관성이 없었다. 또한 첨두유출비(QP/Q)는 AMC I조건에서 3차 및 4차 모멘트와 상관성을 보였으며, AMCIII조건에서는 1차 및 2차 모멘트와 상관성을 보였다. 강우의 전체 지속시간을 고려하는 경우, CN은 AMC I조건에서 모든 시간분포인자와 상관성을 보였으나 AMCIII조건에서는 1차 및 2차 시간분포인자와 상관성을 보였다. 그리고 첨두유출비(QP/Q)는 AMC I조건에서 3차 및 4차 시간분포인자와 상관성을 보였으나 그 외의 조건에서는 거의 상관성을 보이지 않았다. 따라서 보다 정확한 CN 산정을 위해 강우의 시간분포와 제시된 시간분포인자를 고려할 것을 제안하였다.

밤나무에 대한 온도, 광 및 질소시비 조건과 기존 피해 잎이 주둥무늬차색풍뎅이(Adoretus tenuimaculatus) 성충의 유인에 미치는 영향 (Effect of Light, Temperature and Nitrogen Fertilization and Damaged Leaf on the Feeding of Chestnut Brown Chafer, Adoretus tenuimaculatus (Coleoptera: Scarabaeidae))

  • 이동운;추호렬;이상명;이영한
    • 아시안잔디학회지
    • /
    • 제13권3호
    • /
    • pp.159-170
    • /
    • 1999
  • Preference of chestnut brown chafer (CBC), Adoretus tenuimaculatus was examined from chestnut leaves which were treated with different light condition, temperature and nitrogen fertilization. More CBC was attracted to leaves which grown at $30^{\circ}C$ than grown at $20^{\circ}C$,$ 25^{\circ}C$ and in the field. When attracted number of CBC was compared among full sunlight-grown, cloth shaded-grown and dark-grown plants, 4.0 in full sunlight grown and 5.0 in dark-grown plants. Amount of nitrogen fertilizer did not influence CBC feeding. The attractiveness of undamaged leaves with non-feeding beetles, leaves with feeding damaged, and leaves with artificial damaged was compared in replicated laboratory trials by placing the treatments in the petri-dish and counted the number of beetles that landed on the plants after 6 hr treatment. The highest number of beetles was attracted to chestnut leaf with feeding damaged ($7.7\pm$0.6) than undamaged leaf with non-feeding beetles ($5.3\pm$0.6) and artificial damaged ($4.3\pm$0.6). Managnese content in the leaves of chestnut grown in shade cloth-grown condition was higher than that in the leaves of chestnut that had been exposed to full sunlight condition and dark condition, and feeding damaged leaf.

  • PDF

Interpretation of Relationship Between Sesame Yield and It's components under Early Sowing Cropping Condition

  • Shim Kang-Bo;Kang Churl-Whan;Seong Jae-Duck;Hwang Chung-Dong;Suh Duck-Yong
    • 한국작물학회지
    • /
    • 제51권4호
    • /
    • pp.269-273
    • /
    • 2006
  • Multiple linear regression analysis was conducted to interpretate the relationship between sesame grain yield and its components under early sowing cropping condition. The t test showed that stem length, number of capsules per plant, 1000 seeds weight and seed weight per plant gave significant contribution to sesame grain yield, therefore those variables were assumed to mostly influenced components to grain yield of sesame. In the stepwise regression analysis, the predicted equation for sesame grain yield per square meter (Y) was Y = -7.900 + 0.150X1 + 0.461X5 + 15.553X6 + 8.543X7. Meanwhile, F value showed that stem length, number of capsules per plant and seed weight per plant gave significant contribution to sesame grain yield, while 1000 seeds weight did not significantly show. Based on the results, it is reasonable to assume that high yield. potential of sesame under early sowing cropping condition would be obtained by selecting breeding lines with long stem length, number of capsules per plant, and seed weight per plant, which was different result at the late sowing cropping condition in which days to flowering and maturity were assumed to be more affected factors to the sesame grain yield.

일부 농촌지역 노인의 일반 특성 및 구강상태와 치주염유발세균의 관련성 (Association of periodontitis-related bacteria complex with socio-demographic and oral health condition among the elderly in a rural area)

  • 이승근;정은재;김지혜;송근배;최연희
    • 한국치위생학회지
    • /
    • 제20권5호
    • /
    • pp.743-752
    • /
    • 2020
  • Objectives: The objectives of this study were to investigate the distribution and level of periodontopathic bacteria with the general characteristics and oral health condition of the elderly. Methods: A total of 335 elderly individuals aged 65 years or older who lived in Ganghwa-gun, Incheon, were included in the study. Oral examination, investigation through a questionnaire, and collection of saliva were carried out. The collected saliva was analyzed for the distribution and levels of bacteria (red and orange complex bacteria) by real-time polymerase chain reaction. Statistical analyses were performed using chi-square test, t-test, one-way analysis of variance, and Pearson's correlation coefficient with SAS statistical software version 9.4. Results: Among the general characteristics, there were significant differences in the distribution of Porphyromonas gingivalis, Treponema denticola, and Parvimonas micra depending on sex, age, and dental visits (p<0.05). The number of remaining teeth and denture use were related to the distribution of periodontopathic bacteria, except T. denticola (p<0.05). Additionally, periodontitis was related to the distribution of P. gingivalis (p<0.05). As the number of remaining teeth increased, the copy number of red and orange complex bacteria also increased (p<0.05). Those individuals who did not use dentures and had periodontal disease had more periodontopathic bacteria (p<0.05). Conclusions: The distribution and copy number of periodontopathic bacteria in the elderly were more related to oral health condition than to general characteristics. In particular, the distribution and copy number of periodontopathic bacteria were higher in subjects with multiple remaining teeth, no dentures, and periodontal disease.

지방 일개도시 PC방에서의 실내공기중 TSP농도와 TSP내 중금속 농도 (The Concentration of TSP and Heavy Metals in the Indoor Air of Local PC Rooms)

  • 차현수
    • 한국보건간호학회지
    • /
    • 제16권1호
    • /
    • pp.190-200
    • /
    • 2002
  • This study was carried out to investigate and analyze TSP of the PC rooms. The concentration of the total suspended particulate and heavy metals contained in the total suspended particulate of the 15 PC rooms located in one local city were measured. The statistical correlation coefficients between the total suspended particulate and factors of the indoor condition (number of fan or size of pc room, illumination), between the heavy metals and factors of the indoor condition were studied. The results are as follows: 1. The factors of the indoor condition of the 15 PC rooms are as follows. Average illumination was 24 luxes. Average number of computers installed were 37. Average number of the fans was 7. and the size of investigated PC rooms was $139.94m^2$. 2. The mean age of the subjects was 21.8 years old. they $(51.5\%)$ used the 15 pc rooms for fewer than 2 hours per one day. 3. The mean concentration of total suspended particulate (TSP) is lower in the evening ${139.085\;(2.462)\;{\mu}g/m^3}$ than the night ${166.216(2.609){\mu}g/m^3}$. 4. The mean concentration of total suspended particulate was industrial work area) residential area) commercial area. 5. The distribution of heavy metals were indicated as Zn>Cr>Pb>Cd in the indoor air at PC rooms. and the concentration rate of Zn was the highest among heavy metals. but this increase didn't show any relationship with many factors of indoor condition (number of fan or size of pc room, lighting) 6. The concentration of TSP & heavy metals didn't have any relationship between the factors of indoor environment (number of fans, size of pc room, lighting).

  • PDF