• Title/Summary/Keyword: Fatigue Life

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The Relationship of Symptoms of Side Effects, Fatigue and Quality of Life in Stomach Cancer Patients receiving Chemotherapy (수술후 화학요법받는 위암환자의 부작용 증상, 피로 및 삶의 질과의 관계)

  • Yang, Young-Hee
    • Korean Journal of Adult Nursing
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    • v.14 no.2
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    • pp.205-212
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    • 2002
  • Purpose: The purpose of this study was to investigate the level of nausea, vomiting, anorexia, fatigue and quality of life as well as to determine the relationship between those variables and identify the influencing factors on fatigue and quality of life in stomach cancer patients receiving adjuvant chemotherapy. Method: Subjects were 94 stomach cancer patients undergoing postoperational chemotherapy in a general hospital in Seoul. Nausea and vomiting were measured with Rhodes et al(1984) and anorexia with one 5-point item. Fatigue was measured using Lee's tool(1999) except open questions. The tool for quality of life was modified based on the Quality of Life Index by Padilla et al(1983). Result: Subjects reported low level of fatigue(mean=3.86, range=0-10) compared with the results of previous researches and moderate quality of life(mean=2.64, range=1-4). Fatigue was positively correlated with nausea, vomiting and anorexia(r=.21 ~ .55, p<.05). Quality of life was negatively correlated with nausea, vomiting, anorexia(r= -.24 ~ -.45, p<.05) and fatigue (r=-.61, p<.01). Multiple regression analysis revealed that activity level, vomiting before admission, anorexia during chemotherapy and age explained 52.8% of the variance in fatigue. Fatigue, anorexia before admission, age and sex explained 50.5% of the variance in quality of life. Fatigue and quality of life were not influenced by the stage of disease, nor weight change. Conclusion: These results may contribute to a better understanding of how much the side effects of anticancer drugs can affect fatigue and quality of life in cancer patients undergoing chemotherapy. Also it is the remarkable fact that symptoms remaining after discharge such as vomiting or anorexia continued until re-admission, contributing to patients fatigue and lowered their quality of life.

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A Study on the Fatigue Crack Propagation Behavior of Cr-Mo-V Alloy with Micro Defects at High Temperature. (미소 원공결함을 갖는 Cr-Mo-V강의 고온피로 크랙전파거동)

  • Song, Samhong;Kang, Myungsoo
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.12
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    • pp.70-77
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    • 1996
  • Fatigue tests were carried out at high temperature on a Cr-Mo-V steel in order to assess the fatigue life of components used in power plants. The characteristics of high temperature fatigue were divided in terms of cycle-dependent fatigue and time-dependent fatigue, each crack propagation rate was examined with respect to fatigue J-integral range, .DELTA. J$_{f}$and creep J-integral range, .DELTA. J$_{c}$. The fatigue life was evaluated by analysis of J-integral value at the crack tip with a dimensional finite element method. The results obtained from the present study are summarized as follows : The propagation characteristics of high temperature fatigue cracks are determined by .DELTA. J$_{f}$for the PP(tensile plasticity-compressive plasticity deformation) and PC(tensile plasticity - compressive creep deformation) stress waveform types, and by .DELTA. J$_{c}$for the CP(tensile creep- compressive plasticity deformation) stress waveform type. The crack propagation law of high temperature fatigue is obtained by analysis of J-integral value at the crack tip using the finite element method and applied to examine crack propagation behavior. The fatigue life is evaluated using the results of analysis by the finite element method. The predicted life and the actual life are close, within a factor of 2.f 2.f 2.

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Effects of Pain, Sleep Disturbance, and Fatigue on the Quality of Life in Patients with Pancreatic Cancer Undergoing Chemotherapy (항암화학요법을 받는 췌장암 환자의 통증, 수면장애, 피로가 삶의 질에 미치는 영향)

  • Kim, Gyung-Duck;Jang, Hyun-Jin
    • Asian Oncology Nursing
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    • v.12 no.2
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    • pp.117-124
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    • 2012
  • Purpose: The purpose of this study was to assess pain, sleep disturbance, fatigue, and the quality of life and to identify the impact of pain, sleep disturbance and fatigue on the quality of life in patients with pancreatic cancer undergoing chemotherapy. Methods: Data were collected from June to July, 2010. Participants were recruited from Y university hospital in Seoul. Research instruments included numeric rating scale for pain, Functional Assessment Chronic Illness Therapy-Functional Well-Being (FACIT-FWB): General Factor 5 (GF5) for sleep disturbance, Functional Assessment of Cancer Therapy-General (FACT-G) for quality of life, and FACT-Fatigue for fatigue. Results: The quality of life for cancer patients had a significant relationship with pain, sleep disturbance, and fatigue. The significant factors influencing quality of life were pain, sleep disturbance, and fatigue that explained 52.6% of the variance. Conclusion: Patients with pancreatic cancer undergoing chemotherapy experienced pain, fatigue, and sleep disturbance which led to a negative effect on quality of life. The results suggest that intervention program to improve quality of life could reduce pain, fatigue, and sleep disturbance of pancreatic cancer patients undergoing chemotherapy.

A fuzzy residual strength based fatigue life prediction method

  • Zhang, Yi
    • Structural Engineering and Mechanics
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    • v.56 no.2
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    • pp.201-221
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    • 2015
  • The fatigue damage problems are frequently encountered in the design of civil engineering structures. A realistic and accurate fatigue life prediction is quite essential to ensure the safety of engineering design. However, constructing a reliable fatigue life prediction model can be quite challenging. The use of traditional deterministic approach in predicting the fatigue life is sometimes too dangerous in the real practical designs as the method itself contains a wide range of uncertain factors. In this paper, a new fatigue life prediction method is going to be proposed where the residual strength is been utilized. Several cumulative damage models, capable of predicting the fatigue life of a structural element, are considered. Based on Miner's rule, a randomized approach is developed from a deterministic equation. The residual strength is used in a one to one transformation methodology which is used for the derivation of the fatigue life. To arrive at more robust results, fuzzy sets are introduced to model the parameter uncertainties. This leads to a convoluted fuzzy based fatigue life prediction model. The developed model is illustrated in an example analysis. The calculated results are compared with real experimental data. The applicability of this approach for a required reliability level is also discussed.

Fatigue Life Prediction of CFRP using Fatigue Progressive Damage Model (피로누적손상을 이용한 직조 CFRP의 피로수명 예측)

  • Jang, Jae-Wook;Cho, Je-Hyoung;Oh, Dong-Jin;Kim, Myung-Hyun
    • Journal of the Society of Naval Architects of Korea
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    • v.52 no.3
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    • pp.248-254
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    • 2015
  • The strength and fatigue life of Satin and Twill-woven CF/epoxy composite(CFRP) have been investigated. Damage mechanism fatigue method has been used to assess fatigue damage accumulation. It is based on measured residual stiffness and residual strength of carbon-fiber reinforced plastic(CFRP) laminates under cyclic loading. Fatigue damage evolution in composite laminates and predict fatigue life of the laminates were simulated by finite element analysis(FEA) method. The stress analysis was carried out in MSC patran/Nastran. A modified Hashin's failure criterion di rmfjapplied to predict the failure of the experimental data of fatigue life but a Ye-delamination criterion was ignored because of 2D modeling. Almost linear stiffness and strength degradation were observed during most of the fatigue process. These stress distribution data were adopted in the simulation to simulate fatigue behavior and estimate life of the laminates. From the results, the predicted fatigue life is more conservatively estimated than the experimental results.

Fatigue Life Prediction of Stainless Steel Using Acoustic Emission (음향방출법을 이용한 스테인레스강 피로수명 예측)

  • Kim, Y.H.;Jung, C.K.;Yang, Y.C.;Han, K.S.
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.193-198
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    • 2001
  • The feasibility of the acoustic emission technique in predicting the residual fatigue life of STS304 stainless steel is presented. Acoustic emission was continuously monitored during the fatigue tests. Considerable acoustic emission occurred during the first few cycles. Acoustic Emission increased rapidly at about 90% of the fatigue life, clear and ample warning of impending fatigue failure was observed. Fatigue damage accumulation was evaluated in terms of an AE cumulative counts. The AE cumulative counts may be taken as an indicator of fatigue cumulative damage. Fatigue damages corresponding to 20, 40, 60 and 80% of the total life were induced at a cyclic stress amplitude. The specimens with and without fatigue damage were subjected to tensile tests. In tensile tests, the total cumulative counts were reduced with increasing fatigue damage. It was observed that the residual tensile strength of material did not change significantly with prior cyclic loading damages.

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Influence of residual stress due to shot peening on fatigue strength and life (피로강도 및 수명에 미치는 Shot Peening에 의한 잔류응력의 영향)

  • Lee, Jong-Gyu;Kim, Jeong-Gyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.9
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    • pp.1498-1506
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    • 1997
  • Procedures are presented for influence of shot peening on fatigue strength, fatigue life and effects of shot peening are discussed from experiments were taken between shot peened and unpeened SPS5, SM45C specimens. After the residual stress on shot peened specimens was measured by X-ray diffractometer, rotating bending fatigue tests were carried out. In addition, the compressive residual stress profile was obtained by the superposition method of three stresses which is based on Al-Obaid's equation. Predicted fatigue life considering residual stress profile which was obtained by the Al-Obaid's equation and another predicted fatigue life considering residual stress profile which was measured in test were compared. For the purpose of predicting fatigue life, Morrow's equation considering the residual stress and mean stress was used.

Fatigue Life Prediction of Spot Welds in SPCC (냉간압연강판 점용접부의 피로수명예측)

  • 이용복
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1997.04a
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    • pp.137-142
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    • 1997
  • Spot welding has been used in the sheet metal joining processes because of its high productivity and convenience. In this study effects of welding conditions on the fatigue life and predicting methods of fatigue life of spot welded joint have been studied. Fatigue life was estimated by stress index parameter considering multiaxial stresses. Fatigue tests were conducted with the tensile-shear specimens using SPCC. Fatigue life of spot welded joint was influenced by welding currents and was predicted exactly with taking into account Stage III.

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Fatigue Life Predictions for Variable Load Histories - Part II : Computer Software for Predictions of Fatigue Crack Initiation Life - (變動荷重下의 疲勞壽命 豫測 第2報)

  • 이시중;송지호;하재선
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.6
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    • pp.1350-1357
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    • 1988
  • A computer software was developed for predictions of fatigue crack initiation life of notched members under variable loadings. The software was constructed based on a new fatigue life prediction method utilizing modified .epsilon.-N curves, which can account for the stress interaction effect. The effect of mean plastic strain on low-cycle fatigue life was also incorporated in the software. The software can be utilized for the first step approximation when fundamental data of material fatigue properties are not available.

Trajectory of Fatigue, Quality of Life and Physical Symptoms in Cancer Patients Receiving Radiotherapy (방사선 치료를 받는 암환자의 피로, 삶의 질 및 신체 증상의 변화 양상)

  • 양영희
    • Journal of Korean Academy of Nursing
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    • v.33 no.5
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    • pp.562-569
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    • 2003
  • Purpose: The purpose of this longitudinal prospective study was to assess changes in fatigue and quality of life for a 6-week course of radiotherapy. Method: A descriptive and longitudinal design was used to this study. Twenty-three subjects receiving radiotherapy from a radiotherapy clinic of a general hospital completed the questionnaires. Fatigue was measured using Lee's scale(1999) and quality of life using Yang's scale(2002) weekly for 6 weeks. Result: Fatigue significantly increased(F=6.043, p=.000), and quality of life significantly decreased (F=3.938, p=.003) and physical symptoms also significantly increased(F=2.432, p=.039) during a 6-week radiotherapy. Multiple regression analysis revealed that fatigue at the first week and physical symptoms at the 6th week were the significant affecting variables(60.1% of the variance) on fatigue. And 63.2% of the variance in quality of life was explained by quality of life and fatigue at the first week and body weight change for 6 weeks radiotherapy. Conclusion: Based on these results, the fatigue and quality of life at the beginning time of radiotherapy have a lasting impact throughout the course of treatment. It suggests that nurses provide patients with information about the occurrence of fatigue during radiotherapy and the practical methods of intervening physical symptoms.