• Title/Summary/Keyword: modified method

Search Result 8,761, Processing Time 0.042 seconds

Calculation of the Crack Length for a Pipe Specimen using the Modified Load Ratio Method (수정된 하중비법을 이용한 배관 시험편의 균열 길이 계산)

  • Choi, Jung-Hun;Huh, Yong;Koo, Jae-Mean;Seok, Chang-Sung;Park, Jae-Sil
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.33 no.12
    • /
    • pp.1375-1382
    • /
    • 2009
  • The objective of this paper is to apply the load ratio method to the measurement of the crack length of the real scale pipe specimen. The load ratio method was modified and finite element analyses were performed to derive the relationship between the normalized compliance and the normalized crack length for the pipe specimen. In order to measure the crack length, the direct current potential drop method and the modified load ratio method were applied to the pipe test. The applicability of the modified load ratio method was confirmed by comparing the calculated crack length with the measured crack length from the pipe experiment.

Two Modified T2 Sympathicotomies in Palmar Hyperhidrosis (수장부 다한증에서 두가지 변형된 교감신경절 차단술)

  • 배기만
    • Journal of Chest Surgery
    • /
    • v.32 no.9
    • /
    • pp.818-822
    • /
    • 1999
  • Background: Thoracoscopic T2 sympathicotomy had been performed as a simple and effective method in treating palmar hyperhidrosis, however, this method had the complications of compensatory hyperhidrosis and facial anhidrosis. Therefore, a more limited and modified methods for T2 sympathicotomies were introduced and comparative analysis of the modified upper and lower T2 sympathicotomy were made in the treatment of palmar hyperhidrosis. Material and Method: From January 1997 to December 1998, 41 patients with palmar hyperhidrosis had been treated by modified T2 sympathicotomy at the Kon-Kuk University Seoul Hospital. Twenty-four patients underwent a modified upper T2 sympathicotomy(Group A), and seventeen patients underwent a modified lower sympathicotomy(Group B). A comparison between groups A and B were made according to the medical records and interview results. Result: All patients showed symptomatic improvements after the operation. The anisocoria, facial anhidrosis and dissatisfaction for compensatory hyperhidrosis were more common in Group A and the individual satisfaction for the operations were higher in Group B. Conclusion: The modified lower T2 sympathicotomy might be a more effective and less complicated method than the modified upper T2 sympathicotomy.

  • PDF

Strength Properties of the Mortar According to the Curing Condition of the Modified Sulfur Mortar (개질유황 모르타르의 양생조건에 따른 모르타르의 강도특성)

  • Jung, Byeong-Yeol;Lee, Sang-Soo;Song, Ha-Young
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2013.05a
    • /
    • pp.332-333
    • /
    • 2013
  • This research utilizes the modified sulfur having the low melting point which 65℃ is tries to study the strength property of the mortar according to the cure method of the modified sulfur mortar. And we try to use as basic data for investigating the curing condition of the light panel optimum utilizing the modified sulfur. We experimented by five kinds; 20℃ water curing method and 20, 40, 60, 80(℃) air dry curing method. In 3 day curing, the compressive strength was improved caused by high curing temperature. But the compressive strength was degraded caused by enhanced temperature in 7day curing and 28day curing. Therefore, the curing temperature of the modified sulfur mortar is determined that it comes 20 time case curing and the water curing is the most recommendable.

  • PDF

THE RELIABLE MODIFIED OF ADOMIAN DECOMPOSITION METHOD FOR SOLVING INTEGRO-DIFFERENTIAL EQUATIONS

  • Hamoud, Ahmed A.;Ghadle, Kirtiwant P.
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.32 no.4
    • /
    • pp.409-420
    • /
    • 2019
  • In this article, we discussed semi-analytical approximated methods for solving mixed Volterra-Fredholm integro-differential equations, namely: Adomian decomposition method and modified Adomian decomposition method. Moreover, we prove the uniqueness results and convergence of the techniques. Finally, an example is included to demonstrate the validity and applicability of the proposed techniques.

A Study on the Calculation Scheme of Extreme Loading Point and Nose Curves using Modified N-R and Continuation Method (수정N-R법과 연속음형법을 이용한 임계부하점 및 Nose Curve 산정기법 연구)

  • Yu, In-Keun
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.41 no.7
    • /
    • pp.712-722
    • /
    • 1992
  • Several voltage instability/collapse problems that have occurred in the electric utility industry worldwide have gained the attention of engineers and researchers of electric power systems. This paper proposes an effective calculation scheme of the extreme loading point and nose curves(P-V curves) using modified Newton-Raphson(N-R) load flow method and the Continuation Method. This method provides detail and visual information of the power system voltage profile and operating margin ro operators and planners. In this paper, a modified load flow claculation method for ill-conditioned power systems is introduced for the purpose of seeking more precise load flow solutions and nose curves, and the Continuation Method is also used as a part of the solution algorithm for the calculation of extreme loading point and nose curves. The conventional polar coordinate based N-R load flow program is modified to avoid numerical difficulties caused by the singularity of the Jacobian matrix occuring in the vicinity of extreme loading point of heavily loaded systems. Application results of the proposed method to Klos-Kerner 11-bus system and modified IEE-30-bus system are presented to assure the usefulness of the approach.

  • PDF

Strength Evaluation of Slender Steel Reinforced Concrete Beam-Columns

  • Chung, Jinan;Choi, Seongmo;Kim, Dongkyu
    • Architectural research
    • /
    • v.3 no.1
    • /
    • pp.61-70
    • /
    • 2001
  • The paper is intended to propose design strength of slender steel reinforced beam-columns by using the modified superposed method. The design of composite members is carried out by a superposed strength method in AIJ (Architectural Institute of Japan) design method. The bearing capacities of the steel part and the concrete part have to be determined separately and then added to a combined capacity. Authors have proposed a new superposed method in a modified form for the slender composite beam-columns and reinforced column. The modified superposed method is adopted for the slender steel reinforced beam-columns. Validation of the modified superposed method is undertaken by comparison with analytical results calculated assuming a sine curve deflected shape of the beam-columns, and with the test results conducted in Japan.

  • PDF

On Calculating Eigenvalues In Large Power Systems Using Modified Arnoldi Method

  • Lee, Byong-Jun;Iba, Kenjl;Hirose, Michio
    • Proceedings of the KIEE Conference
    • /
    • 1996.07b
    • /
    • pp.734-736
    • /
    • 1996
  • This paper presents a method of calculating a selective number of eigenvalues in power systems, which are rightmost, or are largest modulus. The modified Arnoldi method in conjunction with implicit shift OR-algorithm is used to calculate the rightmost eigenvalues. Algorithm requires neither a prior knowledge of the specified shifts nor the calculation of inverse matrix. The key advantage of the algorithm is its ability to converge to the wanted eigenvalues at once. The method is compared with the modified Arnoldi method combined with S-matrix transformation, where the eigenvalues having the largest modulus are to be determined. The two methods are applied to the reduced Kansai system. Convergence characteristics and performances are compared. Results show that both methods are robust and has good convergence properties. However, the implicit shift OR method is seen to be faster than the S-matrix method under the same condition.

  • PDF

ON CONVERGENCE OF THE MODIFIED GAUSS-SEIDEL ITERATIVE METHOD FOR H-MATRIX LINEAR SYSTEM

  • Miao, Shu-Xin;Zheng, Bing
    • Communications of the Korean Mathematical Society
    • /
    • v.28 no.3
    • /
    • pp.603-613
    • /
    • 2013
  • In 2009, Zheng and Miao [B. Zheng and S.-X. Miao, Two new modified Gauss-Seidel methods for linear system with M-matrices, J. Comput. Appl. Math. 233 (2009), 922-930] considered the modified Gauss-Seidel method for solving M-matrix linear system with the preconditioner $P_{max}$. In this paper, we consider the modified Gauss-Seidel method for solving the linear system with the generalized preconditioner $P_{max}({\alpha})$, and study its convergent properties when the coefficient matrix is an H-matrix. Numerical experiments are performed with different examples, and the numerical results verify our theoretical analysis.

Evaluation for Performance According to Curing Method of Polymer- Modified Mortars (폴리머 시멘트 모르타르의 양생방법에 따른 물성 평가)

  • Park, Hun-Il;Ryu, Byung-Cheoll;Oh, Sang-Keun
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2005.05b
    • /
    • pp.273-276
    • /
    • 2005
  • Polymer-modified mortar was developed for improving the performance of modified mortar which is mixed with polymer, and it is used for protecting and repairing materials of building because of their excellent performance to improve characteristics which are compressive strength, flexural strength, and adhesive strength. However, the performances of the polymer-modified mortars are highly affected by materials, which are polymer, mortar, and aggregates, and conditions which are curing environment and testing method. Furthermore, dry curing method after hydrated curing has been recommended to make strong polymer film for the best curing method to make excellent characteristics. In this report, We investigated the co-relation between curing methods and the characteristics, which are compressive strength, flexural strength, and adhesive strength for the polymer-modified mortars that are used in the domestic area.

  • PDF

Hydroelastic Response of VLFS with Submerged-Plate Using Modified Hydrodynamic Coefficients

  • Lee, Sang-Min
    • Journal of Navigation and Port Research
    • /
    • v.31 no.7
    • /
    • pp.569-578
    • /
    • 2007
  • The primary objective of this study is to present a modified method of hydroelastic analysis and application of it to the VLFS with submerged plate. The modal analysis method is applied to the VLFS with the submerged plate using the modified hydrodynamic coefficients. Namely, the wave exciting forces are modified by the transmission wave coefficients, while the interaction factor is used for the modification of radiation forces. To validate the proposed method, comparisons between the numerical calculations and experimental data have been carried out for the deflections of VLFS, and it shows good agreement between the calculation and experiment. The results presented in this study demonstrate that the elastic response of the VLFS is strongly affected by the hydrodynamic interaction induced by the submerged plate. As a result, we can confirm that the submerged plate is useful for reducing the hydroelastic deflection of VLFS, and the proposed method is valuable for predicting the elastic response of VLFS with attached the submerged plate.