• Title/Summary/Keyword: Response criteria

검색결과 1,080건 처리시간 0.031초

지진발생에 따른 지중연성관의 거동특성 분석 (Analysis of Behavior for Underground Flexible Pipes Under Seismic Loads)

  • 김경열;홍성연;이대수
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2003년도 봄 학술발표회 논문집
    • /
    • pp.709-716
    • /
    • 2003
  • Flexible pipes (corrugated polyethylene pipes) are normally used for underground power distribution grids. In this paper, dynamic analysis was carried out through FEM in order to investigate the structural behaviour of pipes subjected to seismic loads. The burial depth and the number of pipes were major parameters in the numerical analysis to determine the response of pipes. The results show that the displacement of pipes under given conditions are all satisfactory in comparison of the allowable strain criteria -maximum 3.5 %.

  • PDF

Augmented D-Optimal Design for Effective Response Surface Modeling and Optimization

  • Kim, Min-Soo;Hong, Kyung-Jin;Park, Dong-Hoon
    • Journal of Mechanical Science and Technology
    • /
    • 제16권2호
    • /
    • pp.203-210
    • /
    • 2002
  • For effective response surface modeling during sequential approximate optimization (SAO), the normalized and the augmented D-optimality criteria are presented. The normalized D-optimality criterion uses the normalized Fisher information matrix by its diagonal terms in order to obtain a balance among the linear-order and higher-order terms. Then, it is augmented to directly include other experimental designs or the pre-sampled designs. This augmentation enables the trust region managed sequential approximate optimization to directly use the pre-sampled designs in the overlapped trust regions in constructing the new response surface models. In order to show the effectiveness of the normalized and the augmented D-optimality criteria, following two comparisons are performed. First, the information surface of the normalized D-optimal design is compared with those of the original D-optimal design. Second, a trust-region managed sequential approximate optimizer having three D-optimal designs is developed and three design problems are solved. These comparisons show that the normalized D-optimal design gives more rotatable designs than the original D-optimal design, and the augmented D-optimal design can reduce the number of analyses by 30% - 40% than the original D-optimal design.

Effect of one way reinforced concrete slab characteristics on structural response under blast loading

  • Kee, Jung Hun;Park, Jong Yil;Seong, Joo Hyun
    • Advances in concrete construction
    • /
    • 제8권4호
    • /
    • pp.277-283
    • /
    • 2019
  • In evaluating explosion-protection capacity, safety distance is broadly accepted as the distance at which detonation of a given explosive causes acceptable structural damage. Safety distance can be calculated based on structural response under blast loading and damage criteria. For the applicability of the safety distance, the minimum required stand-off distance should be given when the explosive size is assumed. However, because of the nature of structures, structural details and material characteristics differ, which requires sensitivity analysis of the safety distance. This study examines the safety-distance sensitivity from structural and material property variations. For the safety-distance calculation, a blast analysis module based on the Kingery and Bulmash formula, a structural response module based on a Single Degree of Freedom model, and damage criteria based on a support rotation angle were prepared. Sensitivity analysis was conducted for the Reinforced Concrete one-way slab with different thicknesses, reinforcement ratios, reinforcement yield strengths, and concrete compressive strengths. It was shown that slab thickness has the most significant influence on both inertial force and flexure resistance, but the compressive strength of the concrete is not relevant.

재발성 족외과 점액낭염에 대한 도침요법: 증례 보고 (Effects of Acupotomy Treatment on Relapsed Lateral Malleolar Bursitis: A Case Report)

  • 김재훈;이정희;이윤규;이현종;김재수
    • Korean Journal of Acupuncture
    • /
    • 제36권4호
    • /
    • pp.300-307
    • /
    • 2019
  • Objectives : This study details on a case of acupotomy for relapsed lateral malleolar bursitis. Methods : A 71-year-old woman with lateral malleolar bursitis was treated with acupotomy twice in an outpatient setting. A sterilized, disposable, blade width 0.5 mm × needle length 50 mm sized acupotomy was administered on GB40 and BL62 on each visit. Pain intensity assessment using Numeric Rating Scale (NRS) and the response evaluation criteria was conducted right after each treatment. Results : Pain on NRS declined from 5 to less than 1 after twice of acupotomy treatment. This result was regarded as 'Complete Response' using the response evaluation criteria. There were no side effects during whole treatment procedure at all. Conclusions : It is turned out that acupotomy can have a positive clinical effect on lateral malleolar bursitis in this case without any adverse effect. Further controlled studies on acupotomy for lateral malleolar bursitis are required for clinical application.

재난재해 교육, 대응훈련 모델과 화산재 대비 훈련 시나리오 (Modelsfor Disaster Prevention Education and Training and Scenario for Training on Volcanic Ash Fall)

  • 장은미;박용재;박 경
    • 한국지형학회지
    • /
    • 제25권1호
    • /
    • pp.97-113
    • /
    • 2018
  • Low-frequency geological natural disaster events such as Pohang earthquake have been occurred. As a results, there's a growing recognition on the importance of education and training for low frequency geological disasters in Korea. In spite of many years of scientific researches on volcanic disaster prevention and preparedness on Baekdusan volcano, the results do not provide the proper scenario for the training for volcanic ash event. Fall 3D volcanic ash diffusion model was run based on wind field data for the last five year, assuming Aso Mountain's explosion with volcanic explosion index 5 for seventy two hours. The management criteria values for proper actions in the previous studies were applied to make a scenario for thirteen groups of the disaster response teams such as train transportation, water supply, electrical facilities and human health. The models on the relationship between education and training for disaster prevention and response were suggested to fulfill the scientific and practical training at local level.

면진구조물 내 층응답스펙트럼 작성을 위한 고려사항 (Considerations for the Generation of In-Structure Response Spectra in Seismically Isolated Structures)

  • 이승재;김정한
    • 한국지진공학회논문집
    • /
    • 제26권2호
    • /
    • pp.95-103
    • /
    • 2022
  • In order to evaluate the earthquake safety of equipment in structures, it is essential to analyze the In-Structure Response Spectrum (ISRS). The ISRS has a peak value at the frequency corresponding to the structural vibration mode, but the frequency and amplitude at the peak can vary because of many uncertain parameters. There are several seismic design criteria for ISRS peak-broadening for fixed base structures. However, there are no suggested criteria for constructing the design ISRS of seismically isolated structures. The ISRS of isolated structures may change due to the major uncertainty parameter of the isolator, which is the shear stiffness of the isolator and the several uncertainty parameters caused by the nonlinear behavior of isolators. This study evaluated the effects on the ISRS due to the initial stiffness of the bi-linear curve of isolators and the variation of effective stiffness by the input ground motion intensity and intense motion duration. Analyzing a simplified structural model for isolated base structure confirmed that the ISRS at the frequency of structural mode was amplified and shifted. It was found that the uncertainty of the initial stiffness of isolators significantly affects the shape of ISRS. The variation caused by the intensity and duration of input ground motions was also evaluated. These results suggested several considerations for generating ISRS for seismically isolated structures.

여가활동 소비자의 패션관여와 의복선택기준, 패션정보원에 관한 연구 (A Study on the Fashion Involvement, Clothing Selection Criteria and Fashion Information Sources of Leisure Activities Consumers)

  • 제은숙
    • 복식
    • /
    • 제61권7호
    • /
    • pp.51-66
    • /
    • 2011
  • The study is intended to suggest the differentiated and subdivided indexes of the leisure fashion market and to provide the marketing strategy establishment and in-depth understanding of leisure fashion business by looking into the correlation between and among fashion involvement, clothing selection criteria and fashion information sources. This study was conducted by the questionnaire response method and the results were derived by using the SPSS 16.0 statistics program. The results of the study were as follows; 1) As a result of researching the difference between the leisure activities consumer groups and fashion involvement, there were significant differences in emotional and cognitive involvement. In the tour activity group and social activity group, emotional involvement was found to be higher than the cognitive experience while in the hobby and sports activity group, both involvements were equally as high. 2) As a result of researching the difference between the leisure activities groups and clothing selection criteria, it was found that the intrinsic and extrinsic criteria were high in the hobby and sports activity group and that the intrinsic criteria was high in the tour activity group and social activity group. 3) In the difference between the leisure activity groups and fashion information sources, it was found that media source, observation source and experience/personal source were high in the hobby and sports activity group. In addition, the experience and personal source were high in the social activity group. 4) In the difference between and among fashion involvement, clothing selection criteria and fashion information sources, it was found that the emotional involvement, intrinsic criteria and observation source were higher in the group of females than males. 5) In the difference between and among fashion involvement, clothing selection criteria and fashion information sources depending on the ages of leisure activities consumers, it was found that the emotional involvement and observation source were high in the group of 20-24 yrs old consumers and that the emotional involvement, intrinsic criteria and observation source were high in the group of 25-29 yrs old consumers. Also, in the group of 30-34 yrs old consumers, the emotional involvement, observation source and experience/personal source were high.

고온에서의 콘크리트 재료모델과 열거동해석 (Material Model and Thermal Response Analysis of Concrete at Elevated Temperatures)

  • 강석원;홍성걸
    • 콘크리트학회논문집
    • /
    • 제13권3호
    • /
    • pp.268-276
    • /
    • 2001
  • 본 논문은 고온에서의 콘크리트 재료모델을 연구하였다. 콘크리트 응력-변형률 곡선은 온도가 증가함에 따라 그 형태가 변한다. 온도에 따른 콘크리트 재료거동의 변화를 나타내기 위하여 변형된 Saenz 제안식을 이용하여 응력-변형률 관계를 표시하였다. 고온에서의 급격한 변형률의 증가현상을 설명하기 위하여, 콘크리트의 변형률 성분을 순수 열팽창 변형률, 열적크리프 변형률, 과도 변형률 및 역학적 변형률로 구분하여 나타내었다. 열적크리프 변형률은 Baily-Norton의 장기크리프 곡선 식을 수정.제안하여 1축 실험 결과를 온도, 시간 및 응력의 함수로 표현하였고, 또한 유효응력 및 유효변형률 개념을 도입하여 다차원에서도 적용할 수 있는 모델을 제시하였다. 과도 변형률을 제안하여 다공탄성 거동을 가정한 콘크리트 내에 포함된 공극 및 수분의 작용을 역학적 거동의 영향을 분석하고자 하였다. 마지막으로, 본 논문에서 제시한 고온에서의 콘크리트 재료모델을 이용한 해석결과를 실제 화재실험자료와 비교하였다.

위암 및 간암환자의 치료에 있어 양.한방 협진의 효과에 관한 임상시험 (Clinical Study of the Efficacy of Combined Western-Oriental Medicine for Gastric Cancer and Hepatocellular Carcinoma)

  • 이종인;심광용;김호영;최서영;방대건;조경숙
    • 대한한방종양학회지
    • /
    • 제7권1호
    • /
    • pp.117-129
    • /
    • 2001
  • Objectives: We compared the therapeutic response, the treatment-related toxicity, and the improvement of subjective symptoms between the chemotherapy alone group and the western-oriental combined treatment group and evaluated the role of oriental medicine for the improvement of chemotherapy-related toxicity in the advanced gastric cancer and hepatocellular carcinoma. Methods: We evaluated 36 gastric cancer or hepatocellular carcinoma patients(chemotherapy alone group 25 patients, combined treatment group 11 patients) who had been treated in Wonju Christian Hospital and Hana Hospital of Oriental Medicine between June 1999 and October 2000. Enrolled patients' general medical records, results of laboratory and imaging studies, treatment-related toxicities, and subjective symptoms were recorded regularly according to the planned protocol. Therapeutic responses were estimated according to the WHO response criteria and the changes of tumor marker value such as CEA, CA 72-4 and AFP. Results: 1. There was no significant difference of therapeutic response by the WHO response criteria between the two groups(p=.459). 2. There was a significant decrease of tumor marker value in the combined treatment group compared to the chemotherapy alone group(p=.023). 3. There was less comprehensive treatment-related toxicity in the combined treatment group compared to the chemotherapy alone group(p=.037), but there was not a significant difference of comprehensive improvement of subjective symptoms between the two groups(p=.091). Conclusions: Based on the above results, we could expect the possibility of improvements in therapeutic response and treatment-related toxicity with the western-oriental combined anticancer treatment.

  • PDF

Finite element simulations on the ultimate response of extended stiffened end-plate joints

  • Tartaglia, Roberto;D'Aniello, Mario;Zimbru, Mariana;Landolfo, Raffaele
    • Steel and Composite Structures
    • /
    • 제27권6호
    • /
    • pp.727-745
    • /
    • 2018
  • The design criteria and the corresponding performance levels characterize the response of extended stiffened end-plate beam-to-column joints. In order to guarantee a ductile behavior, hierarchy criteria should be adopted to enforce the plastic deformations in the ductile components of the joint. However, the effectiveness of thesecriteria can be impaired if the actual resistance of the end-plate material largely differs from the design value due to the potential activation of brittle failure modes of the bolt rows (e.g., occurrence of failure mode 3 in the place of mode 1 per bolt row). Also the number and the position of bolt rows directly affect the joint response. The presence of a bolt row in the center of the connection does not improve the strength of the joint under both gravity, wind and seismic loading, but it can modify the damage pattern of ductile connections, reducing the gap opening between the end-plate and the column face. On the other hand, the presence of a central bolt row can influence the capacity of the joint to resist the catenary actions developing under a column loss scenario, thus improving the joint robustness. Aiming at investigating the influence of these features on both the cyclic behavior and the response under column loss, a wide range of finite element analyses (FEAs) were performed and the main results are described and discussed in this paper.