• Title/Summary/Keyword: shock response analysis

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Development of the vibration control devices and the optimal base-isolation design system for Structures (구조물 진동제어장치 개발 및 최적 면진설계 시스템 개발)

  • Kim, Byung-Hyun;Chung, Jung-Hoon;Moon, Seok-Jun;Huh, Young-Cheol;Chung, Jong-Ahn
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.375-380
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    • 2004
  • Seismic Isolation and Shock/vibration Control Laboratory has performed the National Research Laboratory(NRL) project, 'Design and Application of Control Devices against Earthquake/Shock/Vibration'. In this project, the prototypes of the vibration control devices for structural control against earthquake and wind were developed and verified their performances. And also, the computer programs were developed for the seismic response analysis and the optimum design of the base-isolated structures with vibration control devices. This paper introduces the developed vibration control devices and computer programs.

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A Speed Control for the Reduction of the Shift Shocks in Electric Vehicles with a Two-Speed AMT

  • Kim, Young-Ki;Kim, Hag-Wone;Lee, In-Seok;Park, Sung-Min;Mok, Hyung-Soo
    • Journal of Power Electronics
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    • v.16 no.4
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    • pp.1355-1366
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    • 2016
  • In the present paper, a speed control algorithm with fast response characteristics is proposed to reduce the shift shock of medium/large-sized electric vehicles equipped with a two-speed AMT. Shift shocks, which are closely related with to the vehicles' ride comfort, occur due to the difference between the speed of the motor shaft and the load shaft when the gear is engaged. The proposed speed control method for shift shock reduction can quickly synchronize speeds occurring due to differences in the gear ratios during speed shifts in AMT systems by speed command feed-forward compensation and a state feedback controller. As a result, efficient shift results without any shift shock can be obtained. The proposed speed control method was applied to a 9 m- long medium- sized electric bus to demonstrate the validity through a simulated analysis and experiments.

Effects of a mild heat treatment on mouse testicular gene expression and sperm quality

  • Zhao, Jun;Zhang, Ying;Hao, Linlin;Wang, Jia;Zhang, Jiabao;Liu, Songcai;Ren, Bingzhong
    • Animal cells and systems
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    • v.14 no.4
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    • pp.267-274
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    • 2010
  • The decrease in sperm quality under heat stress causes a great loss in animal husbandry production. In order to reveal the mechanism underlying the sperm quality decrease caused by heat stress, we first established a mild heat-treated mouse model. Then, the sperm quality was identified. Further, the testicular proteome profile was mapped and compared with the control using 2D electrophoresis and mass spectrometry. Finally, the differential expressed proteins involved in the heat stress response were identified by real-time PCR and Western blotting. The results showed that heat stress caused a significant reduction in mouse sperm quality (P<0.05). Further, 52 protein spots on the 2D gel were found to differ between the heat-shocked tissues and the control. Of these spots, some repair proteins which might provide some explanation for the influence on sperm quality were found. We then focused on Bag-1, Hsp40, Hsp60 and Hsp70, which were found to be differently expressed after heat shock (P<0.05). Further analysis in this heat-shocked model suggests numerous potential mechanisms for heat shock-induced spermatogenic disorders.

Effect of Damping Coefficients in Earthquakes Resistant Design with Viscous Dampers for Bridges (교량의 내진설계에 있어서 점성감쇠기능받침의 감쇠계수 영향평가)

  • 정상모
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.10a
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    • pp.399-406
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    • 2000
  • Viscous dampers have been utilized as bearings and STU`s (Shock Transmission Unit) in earthquake resistant designs for bridges. Some viscous dampers are used as energy dissipators on one hand, but some dampers such as STU`s are used as fixing devices during an earthquake on the other hand. This paper discusses the effect of viscous dampers on the response of bridge with respect to the magnitude of damping coefficients. For this purpose, a typical bridge was taken as an example, and time-history dynamic analysis have been carried out. The input seismic data used in the analyses are relevant to the response spectra in the Koreans design code. The results show that there is an optimum value of coefficient considered most effective in the design. A STU with a large value of coefficient seems to make its support fixed. The response of the bridge is not much sensitive to the variation of the damping coefficients.

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FEA of the blast loading effect on ships hull

  • Hamdoon, Muhsin;Zamani, Nader;Das, Sreekanta
    • Ocean Systems Engineering
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    • v.1 no.3
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    • pp.223-239
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    • 2011
  • In combat operations, naval ships may be subjected to considerable air blast and underwater shock loads capable of causing severe structural damage. As the experimental study imposes great monetary and time cost, the numerical solution may provide a valuable alternative. This study emphasises on numerical analysis for optimization of stiffened and unstiffened plate's structural response subjected to air blast load. Linear and non linear finite element (FE) modeling and analysis was carried out and compared with existing experimental results. The obtained results reveal a good agreement between numerical and experimental observations. The presented FE models can eliminate confusion regarding parameters selection and FE operations processing, using commercial software available currently.

Development and Testing of an Instrument to Measure Family's Emotional Response toward Physically Restrained Patients (억제대 적용해 대한 가족의 정서적 반응 측정 도구개발)

  • Lee, Eun-Nam;Ha, Su-Jin;Kang, Ji-Yeon
    • Journal of Korean Academy of Nursing
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    • v.38 no.4
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    • pp.629-638
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    • 2008
  • Purpose: This was a methodological research to develop an instrument to assess the emotional response of family members of physically restrained patients. Methods: A primary instrument with 68 questions was developed based on literature review and semi-structured interviews with family members. A group of experts revised individual questions and removed 4 irrelevant questions. This secondary instrument, then, was tested with 199 family members of physically restrained patients in intensive care units of a university hospital. The validity and reliability of the instrument were tested by factor analysis. Results: After item analysis, 3 questions with a correlation coefficient under .30 were discarded and the questions with a factor loading under .45 on Varimax Rotation were also removed. After factor analysis on the final 37 questions, 7 factors were identified; avoidance, shock, helplessness, grudge, depression, anxiousness, and acceptance. The total variance explained was 55.63%. The reliability of this instrument was 0.93 of Cronbach's alpha. Conclusion: This instrument was statistically reliable and valid to measure family's emotional response to physical restraints of the patients. This instrument can be useful in assessing the effects of nursing interventions for family members of restrained patients.

Emotional Response of ICU Patients' Family toward Physical Restraints (중환자실 환자의 억제대 적용에 대한 가족의 정서적 반응)

  • Kang, Jiyeon;Lee, Eun-Nam;Park, Eun Young;Lee, Youngock;Lee, Mi Mi
    • Korean Journal of Adult Nursing
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    • v.25 no.2
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    • pp.148-156
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    • 2013
  • Purpose: The purpose of this study was to investigate the emotional response of family members of physically restrained patients in the intensive care units (ICUs). Methods: The study subjects were 200 family members of ICU patients who had been on physical restraints in two university hospitals. Data were collected using the "Instrument of family's emotional response toward physically restrained patients". Results: The mean score of familial emotional response was 2.69 out of a possible 5. The subcategory of acceptance was the highest with 3.56 points followed by depression (3.02), helplessness (2.94), anxiety (2.87), shock (2.74), avoidance (2.64), and grudge (2.08). Multiple stepwise regression analysis indicated that the age of family members, side effects of restraints, and information provision were the variables influencing on negative emotional response of family. Conclusion: Family members showed slightly negative emotional response toward the physical restraints. This finding could be influenced by their limited knowledge of the need for the restraints. Educational programs or fact sheets to be given to family members may be helpful.

Robust immunoreactivity of teenager sera against peptide 19 from Porphyromonas gingivalis HSP60

  • Kwon, Eun-Young;Cha, Gil Sun;Joo, Ji-Young;Lee, Ju-Youn;Choi, Jeomil
    • Journal of Periodontal and Implant Science
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    • v.47 no.3
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    • pp.174-181
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    • 2017
  • Purpose: Epitope spreading is a phenomenon in which distinct subdominant epitopes become major targets of the immune response. Heat shock protein (HSP) 60 from Porphyromonas gingivalis (PgHSP60) and peptide 19 from PgHSP60 (Pep19) are immunodominant epitopes in autoimmune disease patients, including those with periodontitis. It remains unclear whether Pep19 is a dominant epitope in subjects without periodontitis or autoimmune disease. The purpose of this study was to determine the epitope spreading pattern and verify Pep19 as an immunodominant epitope in healthy teenagers using dot immunoblot analysis. The patterns of epitope spreading in age-matched patients with type 1 diabetes mellitus (type 1 DM) and healthy 20- to 29-year old subjects were compared with those of healthy teenagers. Methods: Peptide from PgHSP60, Mycobacterium tuberculosis HSP60 (MtHSP60), and Chlamydia pneumoniae HSP60 (CpHSP60) was synthesized for comparative recognition by sera from healthy subjects and patients with autoimmune disease (type 1 DM). Dot immunoblot analysis against a panel of peptides of PgHSP60 and human HSP60 (HuHSP60) was performed to identify epitope spreading, and a densitometric image analysis was conducted. Results: Of the peptide from PgHSP60, MtHSP60, and CpHSP60, PgHSP60 was the predominant epitope and was most consistently recognized by the serum samples of healthy teenagers. Most sera from healthy subjects and patients with type 1 DM reacted more strongly with PgHSP60 and Pep19 than the other peptides. The relative intensity of antibody reactivity to Pep19 was higher in the type 1 DM group than in the healthy groups. Conclusions: Pep19 is an immunodominant epitope, not only in autoimmune disease patients, but also in healthy young subjects, as evidenced by their robust immunoreactivity. This result suggests that the Pep19-specific immune response may be an initiator that triggers autoimmune diseases.

Blast Analysis of Single Degree of Freedom Plant Structures Considering Static Displacement (정적변위를 고려한 플랜트 구조물의 단자유도 폭발 해석)

  • Lee, Jae-Kyoon;Lee, Seung-Hoon;Kim, Han-Soo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.35 no.5
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    • pp.317-324
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    • 2022
  • In this paper, an analysis method that considers the initial static displacement of structural members using an equivalent single-degree-of-freedom system is presented. Newmark's dynamic analysis algorithm was improved to consider the effect of the initial static displacements of structural members. The effect of the initial static displacement on the maximum response according to the assumed duration of the blast load and natural period of the member was investigated. The effects of positive and negative static displacements on the maximum dynamic responses of structural members subjected to a positively applied blast load were also studied. Modified response charts for the shock-type and pressure-type waves are presented so that static displacements can easily be considered. Using a design example, we demonstrate the significance of the modified response chart that considers the static displacement. Based on the results of this study, the maximum response of a the structural member can be easily obtained whilst considering its initial static displacement. The modified response chart presented in this study can be used for the structural design of plants and military facilities.