• Title/Summary/Keyword: Response criteria

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

  • 김경열;홍성연;이대수
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.709-716
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    • 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 %.

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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
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    • v.16 no.2
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    • pp.203-210
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    • 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
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    • v.8 no.4
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    • pp.277-283
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    • 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.

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

  • Kim, Jae Hoon;Lee, Jung Hee;Lee, Yun-Kyu;Lee, Hyun-Jong;Kim, Jae Soo
    • Korean Journal of Acupuncture
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    • v.36 no.4
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    • pp.300-307
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    • 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.

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

  • Chang, Eunmi;Park, Yongjae;Park, Kyeong
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.1
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    • pp.97-113
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    • 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.

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

  • Lee, Seung Jae;Kim, Jung Han
    • Journal of the Earthquake Engineering Society of Korea
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    • v.26 no.2
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    • pp.95-103
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    • 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.

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

  • Je, Eun-Suk
    • Journal of the Korean Society of Costume
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    • v.61 no.7
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    • pp.51-66
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    • 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.

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

  • 강석원;홍성걸
    • Journal of the Korea Concrete Institute
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    • v.13 no.3
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    • pp.268-276
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    • 2001
  • A numerical model for the thermal response analysis of concrete structures is suggested. The model includes the stress-strain relationship, constitutive relationship, and multiaxial failure criteria at elevated temperature conditions. Modified Saenz's model was used to describe the stress-strain relationship at high temperatures. Concrete subjected to elevated temperatures undergoes rapid strain increase and dimensional instability. In order to explain those changes in mechanical properties, a constitutive model of concrete subjected to elevated temperature is proposed. The model consists of four strain components; free thermal creep strain, stress-induced (mechanical) strain, thermal creep strain, and transient strain due to moisture effects. The failure model employs modified Drucker-Prager model in order to describe the temperature dependent multiaxial failure criteria. Some numerical analyses are performed and compared with the experimental results to verify the proposed model. According to the comparison, the suggested material model gives reliable analytical results.

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

  • Lee, Chong-In;Shim, Kwang-Yong;Kim, Ho-Young;Choi, Seo-Young;Bang, Dae-Geon;Cho, Kyung-Sook
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.7 no.1
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    • pp.117-129
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    • 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.

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