Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehe...Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehensive overview of recent advancements in the plasma-enabled synthesis of life’s building blocks, charting the complex environmental parameters believed to have surrounded life’s inception. This discussion elaborates on the fundamental mechanisms of discharge plasmas and their likely role in fostering conditions necessary for the origin of life on early Earth. We consider a variety of chemical reactions facilitated by plasma, specifically the synthesis of vital organic molecules - amino acids, nucleobases, sugars, and lipids. Further, we delve into the impact of plasmas on prebiotic chemical evolution. We expect this review to open new horizons for future investigations in plasma-related prebiotic chemistry that could offer valuable insights for unraveling the mysteries of life's origin.展开更多
The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service state.This paper proposes a framework for pred...The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service state.This paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible cracks.The hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure modes.The results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack lengths.This study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks.展开更多
In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and quali...In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and qualitative data,is grounded in preferences regarding disability status.This review delineates the algorithm used to calculate the value of the proposed DALY synthetic indicator and elucidates key methodological challenges associated with its application.In contrast to the quality-adjusted life years approach,derived from multi-attribute utility theory,the DALY stands as an independent synthetic indicator that adopts the assumptions of the Time Trade Off utility technique to define Disability Weights.Claiming to rely on no mathematical or economic theory,DALY users appear to have exempted themselves from verifying whether this indicator meets the classical properties required of all indicators,notably content validity,reliability,specificity,and sensitivity.The DALY concept emerged primarily to facilitate comparisons of the health impacts of various diseases globally within the framework of the Global Burden of Disease initiative,leading to numerous publications in international literature.Despite widespread adoption,the DALY synthetic indicator has prompted significant methodological concerns since its inception,manifesting in inconsistent and non-reproducible results.Given the substantial diffusion of the DALY indicator and its critical role in health impact assessments,a reassessment is warranted.This reconsideration is imperative for enhancing the robustness and reliability of public health decisionmaking processes.展开更多
Objective This study examines the sequential mediating roles of body pain and self-reported health in the association between sleep duration and self-reported life satisfaction among elderly Chinese adults.Methods Dat...Objective This study examines the sequential mediating roles of body pain and self-reported health in the association between sleep duration and self-reported life satisfaction among elderly Chinese adults.Methods Data from the fifth wave of the China Health and Retirement Longitudinal Survey(CHARLS)were used to analyse the relationships between sleep duration and body pain,self-reported health,and life satisfaction through logistic regression and Restricted Cubic Spline(RCS)analyses.The sequential mediation effects of body pain and self-reported health status were examined via chain mediation analysis.Results Logistic regression analysis showed that sleeping fewer than 6 hours or 6-7 hours was linked to higher risks of body pain,poor health,and dissatisfaction with life compared to sleeping 7-8 hours(all P<0.05).Additionally,those sleeping more than 9 hours also had increased risks of poor health and dissatisfaction with life compared to those sleeping 7-8 hours(all P<0.05).Chain mediation analysis showed that body pain and self-reported health status sequentially mediated 46.15%of the association between sleep duration and life satisfaction.Conclusion Body pain and self-reported health may shape the relationship between sleep duration and life satisfaction in elderly Chinese adults.展开更多
BACKGROUND Chronic kidney disease(CKD)is an incapacitating illness associated with distressing symptoms(DS)that have negative impact on patients’health-related quality of life(HRQOL).AIM To assess the severity of DS ...BACKGROUND Chronic kidney disease(CKD)is an incapacitating illness associated with distressing symptoms(DS)that have negative impact on patients’health-related quality of life(HRQOL).AIM To assess the severity of DS and their relationships with HRQOL among patients with CKD in Jordan.METHODS A descriptive cross-sectional design was used.A convenience sampling approach was used to recruit the participants.Patients with CKD(n=140)who visited the outpatient clinics in four hospitals in Amman between November 2021 and December 2021 were included.RESULTS The Edmonton Symptom Assessment System was used to measure the severity of the DS while the Short Form-36 tool was used to measure the HRQOL.Participants’mean age was 50.9(SD=15.14).Most of them were males(n=92,65.7%),married(n=95,67.9%),and unemployed(n=93,66.4%).The highest DS were tiredness(mean=4.68,SD=2.98)and worse well-being(mean=3.69,SD=2.43).The highest HRQOL mean score was for the bodily pain scale with a mean score of 68.50 out of 100(SD=32.02)followed by the emotional well-being scale with mean score of 67.60(SD=18.57).CONCLUSION Patients with CKD had suboptimal HRQOL,physically and mentally.They suffer from multiple DS that have a strong association with diminished HRQOL such as tiredness and depression.Therefore,healthcare providers should be equipped with the essential knowledge and skills to promote individualized strategies that focusing on symptom management.展开更多
The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee.In engineering scenarios,only a small amount of bearing performance degradation data can be obtained through acceler...The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee.In engineering scenarios,only a small amount of bearing performance degradation data can be obtained through accelerated life testing.In the absence of lifetime data,the hidden long-term correlation between performance degradation data is challenging to mine effectively,which is the main factor that restricts the prediction precision and engineering application of the residual life prediction method.To address this problem,a novel method based on the multi-layer perception neural network and bidirectional long short-term memory network is proposed.Firstly,a nonlinear health indicator(HI)calculation method based on kernel principal component analysis(KPCA)and exponential weighted moving average(EWMA)is designed.Then,using the raw vibration data and HI,a multi-layer perceptron(MLP)neural network is trained to further calculate the HI of the online bearing in real time.Furthermore,The bidirectional long short-term memory model(BiLSTM)optimized by particle swarm optimization(PSO)is used to mine the time series features of HI and predict the remaining service life.Performance verification experiments and comparative experiments are carried out on the XJTU-SY bearing open dataset.The research results indicate that this method has an excellent ability to predict future HI and remaining life.展开更多
Ernest Hemingway, one of the brightest stars on the literary stage of both American and the whole world literature in the twentieth century, had gained an everlasting reputation by the image of"the tough man"...Ernest Hemingway, one of the brightest stars on the literary stage of both American and the whole world literature in the twentieth century, had gained an everlasting reputation by the image of"the tough man"he created in lots of his works.Hence, to readers, Hemingway must be a strong man both physically and mentally. Though Hemingway had passed away, he left us an inestimable literary treasure, and we can draw some lessons from his suicide tragedy. To modern people who are展开更多
Ernest Hemingway's world-wide influence and distinctive writing style-the Iceberg Style-caused a stylistic revolution in the field of literature all over the world.Hemingway always tries his best to avoid depictin...Ernest Hemingway's world-wide influence and distinctive writing style-the Iceberg Style-caused a stylistic revolution in the field of literature all over the world.Hemingway always tries his best to avoid depicting things by piling gorgeously big words;on the contrary,he adopts direct description and short sentences which are precise,laconic,bright and vivid.For instance,the novel titled The Short and Happy Life of Francis Macomber is universally acknowledged as his masterpiece,in which "Iceberg Theory"is skillfully presented.With a full analysis of the story,the uniqueness of "Iceberg Theory"will be emphasized in this paper.展开更多
The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,...The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,the couple dynamic equations of pantograph–catenary were built with the Lagrange’s method;then the dynamic contact force was obtained by the Newmark method at the train speeds of 250,280 and 300 km/h,respectively.Secondly,the finite element model(FEM)of one anchor section’s catenary was built to analyze its transient response under the contact force as train running;then the loading time history of messenger wire base,steady arm,registration tube,oblique cantilever,and straight cantilever were extracted.Finally,the key components’fatigue spectrum was carried out by the rain-flow counting method,and operation life was estimated in consideration of such coefficients,such as stress concentration,shape and dimension,surface treatment.The results show that the fatigue life of the catenary system reduces with the increasing of train speed;specifically,the evaluated fatigue life of the steady arm is shorter than other components.展开更多
The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center wi...The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center with the demand of high rigidity and heavy load. By means of the study of contact behavior between the roller/guideway and roller/slider, roller type linear guideways can improve the machining accuracy. The goal of this paper is to construct the fatigue life model of the linear guideway, with the help of the contact mechanics of rollers. In beginning, the analyses of the rigidity of a single roller compressed between guideway and slider was conducted. Then, the normal contact pressure of linear guideways was obtained by using the superposition method, and verified by the FEM software (ANSYS workbench). Finally, the bearing life theory proposed by Lundberg and Palmgren was used to describe the contact fatigue life.展开更多
A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to...A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to the total impacts, and to determine how the impacts compare to the primary alternative product, galvanized steel posts. Guard rail posts are the supporting structures for highway guard rails. Transportation engineers, as well as public and regulatory interests, have increasing need to understand the environmental implications of guard rail post selection, in addition to factors such as costs and service performance. This study uses a life cycle inventory (LCI) to catalogue the input and output data from guard rail post manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to assess anthropogenic and net greenhouse gas (GHG), acidification, smog, ecotoxicity, and eutrophication potentially resulting from life cycle air emissions. Other indicators of interest also are tracked, such as fossil fuel and water use. Comparisons of guard rail post products are made at a functional unit of one post per year of service. This life cycle assessment (LCA) finds that the manufacture, use, and disposition of CCA-treated wood guard rails offers lower fossil fuel use and lower anthropogenic and net GHG emissions, acidification, smog potential, and ecotoxicity environmental impacts than impact indicator values for galvanized steel posts. Water use and eutrophication impact indicator values for CCA-treated guard rail posts are greater than impact indicator values for galvanized steel guard rail posts.展开更多
Many studies about the health problems of persons with physical disabilities have been performed, however few studies have focused on the life circumstances of persons with physical disabilities. This study aimed to c...Many studies about the health problems of persons with physical disabilities have been performed, however few studies have focused on the life circumstances of persons with physical disabilities. This study aimed to clarify the relationship between stress and the life circumstances of persons with congenital physical disabilities who must use wheelchairs. The participants were 70 individuals who used the services of care workers employed by welfare service business offices. Participants used wheelchairs. In addition, those participants who used a standard manual wheelchair were not able to operate it alone. Participants were required to answer a two-part questionnaire with questions about factors related to basic lifestyle and stress, and about life factors related to the stress of individuals with physical disabilities. No significant relationship between lifestyle and stress was found in either males or females. Most persons with congenital physical disabilities using wheelchairs had some kind of stress in daily life. In particular, significantly more level of stress was found in females (90%) than that in males (65%). Levels of stress according to life factor differed between males and females. The most dramatic gender difference was that the level of stress caused by the mental or mind factor in females was significantly higher than that in males (p < 0.05). Most persons who must use wheelchairs have stress resulting from daily life, and in particular, females experience more mental stress than males.展开更多
BACKGROUND Having a gynecological tumor or undergoing treatment can be a traumatic experience for women,as it affects their self-image and sexual relationships and can lead to psychological reactions.Psychological adj...BACKGROUND Having a gynecological tumor or undergoing treatment can be a traumatic experience for women,as it affects their self-image and sexual relationships and can lead to psychological reactions.Psychological adjustment following cancer occurrence remains a key issue among the survivors.AIM To examine the current status of quality of life(QoL),anxiety,and depression in patients with gynecological cancer and to analyze the factors associated with it.METHODS Data for 160 patients with gynecological malignancies treated at Shanxi Bethune Hospital from June 2020 to June 2023 were collected and analyzed retrospectively.Patients’QoL was assessed using the European Organization for Research on Treatment of Cancer Quality of Life Questionnaire Core 30 and the Functional Assessment of Cancer Therapy-General Questionnaire.Their emotional status was evaluated using the Self-Rating Anxiety/Depression Scale.The associated factors of anxiety and depression were analyzed.RESULTS The overall QoL score of the patients 6 months after surgery was 76.39±3.63 points.This included low levels of social and emotional function and severe fatigue and pain.The scores for physiological,functional,emotional,social,and family well-being exhibited an upward trend following surgery compared with those before surgery.One month after surgery,some patients experienced anxiety and depression,with an incidence of 18.75%and 18.13%,respectively.Logistic analysis revealed that good sleep was a protective factor against anxiety and depression in patients with gynecological tumors,whereas physical pain was a risk factor.CONCLUSION Patients with gynecological malignancies often experience anxiety and depression.By analyzing the factors that affect patients’QoL,effective nursing measures can be administered.展开更多
<strong>Objective:</strong> This review aims to summarize key facets of the Pro Choice and Pro Life perspectives and outline a resolution pathway that minimizes abortion. <strong>Main Results:</st...<strong>Objective:</strong> This review aims to summarize key facets of the Pro Choice and Pro Life perspectives and outline a resolution pathway that minimizes abortion. <strong>Main Results:</strong> Approximately 1.3 billion abortions occurred worldwide from 1990 through 2014. In the United States, more than 61 million abortions were performed between 1973 and 2017. The Pro Choice perspective posits that: 1) A fetus is not a person;therefore, a person is not harmed. 2) Forced childbearing includes significant health and psychological risks to the mother and can exacerbate poverty. Since a person is not harmed and the mother is benefited, abortion is a moral good. From a Judeo-Christian, Pro Life perspective: 1) God creates every person in his image and has a pre-conception life plan for them. 2) God commanded us to be fruitful and multiply and identified children as a blessing. Hence, abortion harms a person and is rebellion against God. <strong>Conclusion: </strong>In working toward a solution, agape love, which is sacrificial and giving, not selfish or condemning, is a good starting point. In that light, the Judeo-Christian community can begin bridging the chasm between the Pro Life and Pro Choice communities by sharing truth in love and helping to meet the material and emotional needs of pregnant women who see no alternative to abortion. Proactive, unconditional love provides the foundation for making the womb a sanctuary for life.展开更多
Introduction: Otalgia is not only an indicator of impact of disease but also impairs the daily activities and personal behaviors as is unpleasant and disturbing for the patient. It leads to decrease in functional stat...Introduction: Otalgia is not only an indicator of impact of disease but also impairs the daily activities and personal behaviors as is unpleasant and disturbing for the patient. It leads to decrease in functional status up to the complete disability. Nowadays the main focus of physician is to eradicate the disease or the symptoms, leaving behind the humanistic element. In diseased state, the most important point is to assess and improve the quality of life by using multidisciplinary approach. Objective: The objective is to assess the quality of life in patients having otalgia, due to any cause. Methodology: A descriptive cross sectional study was conducted by using modified form of WHOQOL-100 and COQOL. Data was accepted, if CFI was greater than 0.9. Qualitative data were presented as frequency and percentages and quantitative data as mean with standard deviation. ANOVA was used to assess the variations among groups. Change in behavior was assessed by using the Likert scale for each domain of WHOQOL and COQOL by a ten-point scale. Results: Majority of participants about 60.2% were male and were from the age group of 16 - 30 years. Most of the sample population were from lower socioeconomic class. Looking over the WHOQOL-100, higher score represented the higher quality of life. Variation among different socioeconomic status was non-significant for positive attitudes but was highly significant (p = 0.0020) for negative attitudes. Analyzing the COQOL scoring system, higher score reported the worse symptoms. The patient with high COQOL showed strong correlation with poor WHOQOL-100 score that was p value Conclusion: The current study highlights the need of multidisciplinary approach for the better management and improving the quality of life in patients with otalgia.展开更多
The safe and reliable operation of lithium-ion batteries necessitates the accurate prediction of remaining useful life(RUL).However,this task is challenging due to the diverse ageing mechanisms,various operating condi...The safe and reliable operation of lithium-ion batteries necessitates the accurate prediction of remaining useful life(RUL).However,this task is challenging due to the diverse ageing mechanisms,various operating conditions,and limited measured signals.Although data-driven methods are perceived as a promising solution,they ignore intrinsic battery physics,leading to compromised accuracy,low efficiency,and low interpretability.In response,this study integrates domain knowledge into deep learning to enhance the RUL prediction performance.We demonstrate accurate RUL prediction using only a single charging curve.First,a generalisable physics-based model is developed to extract ageing-correlated parameters that can describe and explain battery degradation from battery charging data.The parameters inform a deep neural network(DNN)to predict RUL with high accuracy and efficiency.The trained model is validated under 3 types of batteries working under 7 conditions,considering fully charged and partially charged cases.Using data from one cycle only,the proposed method achieves a root mean squared error(RMSE)of 11.42 cycles and a mean absolute relative error(MARE)of 3.19%on average,which are over45%and 44%lower compared to the two state-of-the-art data-driven methods,respectively.Besides its accuracy,the proposed method also outperforms existing methods in terms of efficiency,input burden,and robustness.The inherent relationship between the model parameters and the battery degradation mechanism is further revealed,substantiating the intrinsic superiority of the proposed method.展开更多
基金National Natural Science Foundation of China General Project(52377160)National Natural Science Foundation of China National Young Talents Project(GYKP010)+1 种基金Shaanxi Provincial Natural Science Program(2023-JC-YB-425)Xi′an Jiaotong University Young Top Talents Program.
文摘Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehensive overview of recent advancements in the plasma-enabled synthesis of life’s building blocks, charting the complex environmental parameters believed to have surrounded life’s inception. This discussion elaborates on the fundamental mechanisms of discharge plasmas and their likely role in fostering conditions necessary for the origin of life on early Earth. We consider a variety of chemical reactions facilitated by plasma, specifically the synthesis of vital organic molecules - amino acids, nucleobases, sugars, and lipids. Further, we delve into the impact of plasmas on prebiotic chemical evolution. We expect this review to open new horizons for future investigations in plasma-related prebiotic chemistry that could offer valuable insights for unraveling the mysteries of life's origin.
基金Supported by National Natural Science Foundation of China (Grant No.52175123)Sichuan Provincial Outstanding Youth Fund (Grant No.22JDJQ0025)Independent Exploration Project of State Key Laboratory of Railway Transit Vehicle System (Grant No.2024RVL-T03)。
文摘The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service state.This paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible cracks.The hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure modes.The results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack lengths.This study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks.
文摘In 1993,the World Bank released a global report on the efficacy of health promotion,introducing the disability-adjusted life years(DALY)as a novel indicator.The DALY,a composite metric incorporating temporal and qualitative data,is grounded in preferences regarding disability status.This review delineates the algorithm used to calculate the value of the proposed DALY synthetic indicator and elucidates key methodological challenges associated with its application.In contrast to the quality-adjusted life years approach,derived from multi-attribute utility theory,the DALY stands as an independent synthetic indicator that adopts the assumptions of the Time Trade Off utility technique to define Disability Weights.Claiming to rely on no mathematical or economic theory,DALY users appear to have exempted themselves from verifying whether this indicator meets the classical properties required of all indicators,notably content validity,reliability,specificity,and sensitivity.The DALY concept emerged primarily to facilitate comparisons of the health impacts of various diseases globally within the framework of the Global Burden of Disease initiative,leading to numerous publications in international literature.Despite widespread adoption,the DALY synthetic indicator has prompted significant methodological concerns since its inception,manifesting in inconsistent and non-reproducible results.Given the substantial diffusion of the DALY indicator and its critical role in health impact assessments,a reassessment is warranted.This reconsideration is imperative for enhancing the robustness and reliability of public health decisionmaking processes.
基金supported by This work was supported by the Ministry of Science and Technology of the People’s Republic of China(STI2030-Major Projects2021ZD0201900)。
文摘Objective This study examines the sequential mediating roles of body pain and self-reported health in the association between sleep duration and self-reported life satisfaction among elderly Chinese adults.Methods Data from the fifth wave of the China Health and Retirement Longitudinal Survey(CHARLS)were used to analyse the relationships between sleep duration and body pain,self-reported health,and life satisfaction through logistic regression and Restricted Cubic Spline(RCS)analyses.The sequential mediation effects of body pain and self-reported health status were examined via chain mediation analysis.Results Logistic regression analysis showed that sleeping fewer than 6 hours or 6-7 hours was linked to higher risks of body pain,poor health,and dissatisfaction with life compared to sleeping 7-8 hours(all P<0.05).Additionally,those sleeping more than 9 hours also had increased risks of poor health and dissatisfaction with life compared to those sleeping 7-8 hours(all P<0.05).Chain mediation analysis showed that body pain and self-reported health status sequentially mediated 46.15%of the association between sleep duration and life satisfaction.Conclusion Body pain and self-reported health may shape the relationship between sleep duration and life satisfaction in elderly Chinese adults.
文摘BACKGROUND Chronic kidney disease(CKD)is an incapacitating illness associated with distressing symptoms(DS)that have negative impact on patients’health-related quality of life(HRQOL).AIM To assess the severity of DS and their relationships with HRQOL among patients with CKD in Jordan.METHODS A descriptive cross-sectional design was used.A convenience sampling approach was used to recruit the participants.Patients with CKD(n=140)who visited the outpatient clinics in four hospitals in Amman between November 2021 and December 2021 were included.RESULTS The Edmonton Symptom Assessment System was used to measure the severity of the DS while the Short Form-36 tool was used to measure the HRQOL.Participants’mean age was 50.9(SD=15.14).Most of them were males(n=92,65.7%),married(n=95,67.9%),and unemployed(n=93,66.4%).The highest DS were tiredness(mean=4.68,SD=2.98)and worse well-being(mean=3.69,SD=2.43).The highest HRQOL mean score was for the bodily pain scale with a mean score of 68.50 out of 100(SD=32.02)followed by the emotional well-being scale with mean score of 67.60(SD=18.57).CONCLUSION Patients with CKD had suboptimal HRQOL,physically and mentally.They suffer from multiple DS that have a strong association with diminished HRQOL such as tiredness and depression.Therefore,healthcare providers should be equipped with the essential knowledge and skills to promote individualized strategies that focusing on symptom management.
基金supported by the National Key Research and Development Project(Grant Number 2023YFB3709601)the National Natural Science Foundation of China(Grant Numbers 62373215,62373219,62073193)+2 种基金the Key Research and Development Plan of Shandong Province(Grant Numbers 2021CXGC010204,2022CXGC020902)the Fundamental Research Funds of Shandong University(Grant Number 2021JCG008)the Natural Science Foundation of Shandong Province(Grant Number ZR2023MF100).
文摘The remaining useful life prediction of rolling bearing is vital in safety and reliability guarantee.In engineering scenarios,only a small amount of bearing performance degradation data can be obtained through accelerated life testing.In the absence of lifetime data,the hidden long-term correlation between performance degradation data is challenging to mine effectively,which is the main factor that restricts the prediction precision and engineering application of the residual life prediction method.To address this problem,a novel method based on the multi-layer perception neural network and bidirectional long short-term memory network is proposed.Firstly,a nonlinear health indicator(HI)calculation method based on kernel principal component analysis(KPCA)and exponential weighted moving average(EWMA)is designed.Then,using the raw vibration data and HI,a multi-layer perceptron(MLP)neural network is trained to further calculate the HI of the online bearing in real time.Furthermore,The bidirectional long short-term memory model(BiLSTM)optimized by particle swarm optimization(PSO)is used to mine the time series features of HI and predict the remaining service life.Performance verification experiments and comparative experiments are carried out on the XJTU-SY bearing open dataset.The research results indicate that this method has an excellent ability to predict future HI and remaining life.
文摘Ernest Hemingway, one of the brightest stars on the literary stage of both American and the whole world literature in the twentieth century, had gained an everlasting reputation by the image of"the tough man"he created in lots of his works.Hence, to readers, Hemingway must be a strong man both physically and mentally. Though Hemingway had passed away, he left us an inestimable literary treasure, and we can draw some lessons from his suicide tragedy. To modern people who are
文摘Ernest Hemingway's world-wide influence and distinctive writing style-the Iceberg Style-caused a stylistic revolution in the field of literature all over the world.Hemingway always tries his best to avoid depicting things by piling gorgeously big words;on the contrary,he adopts direct description and short sentences which are precise,laconic,bright and vivid.For instance,the novel titled The Short and Happy Life of Francis Macomber is universally acknowledged as his masterpiece,in which "Iceberg Theory"is skillfully presented.With a full analysis of the story,the uniqueness of "Iceberg Theory"will be emphasized in this paper.
基金Project(51175383)supported by the National Natural Science Foundation of China(NSF)
文摘The fatigue load spectrum and operation life evaluation of key components in the catenary system under the high speed train running condition were investigated.Firstly,based on the catenary model and pantograph model,the couple dynamic equations of pantograph–catenary were built with the Lagrange’s method;then the dynamic contact force was obtained by the Newmark method at the train speeds of 250,280 and 300 km/h,respectively.Secondly,the finite element model(FEM)of one anchor section’s catenary was built to analyze its transient response under the contact force as train running;then the loading time history of messenger wire base,steady arm,registration tube,oblique cantilever,and straight cantilever were extracted.Finally,the key components’fatigue spectrum was carried out by the rain-flow counting method,and operation life was estimated in consideration of such coefficients,such as stress concentration,shape and dimension,surface treatment.The results show that the fatigue life of the catenary system reduces with the increasing of train speed;specifically,the evaluated fatigue life of the steady arm is shorter than other components.
文摘The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center with the demand of high rigidity and heavy load. By means of the study of contact behavior between the roller/guideway and roller/slider, roller type linear guideways can improve the machining accuracy. The goal of this paper is to construct the fatigue life model of the linear guideway, with the help of the contact mechanics of rollers. In beginning, the analyses of the rigidity of a single roller compressed between guideway and slider was conducted. Then, the normal contact pressure of linear guideways was obtained by using the superposition method, and verified by the FEM software (ANSYS workbench). Finally, the bearing life theory proposed by Lundberg and Palmgren was used to describe the contact fatigue life.
文摘A cradle-to-grave life cycle assessment is done to identify the environmental impacts of chromated copper arsenate (CCA)-treated timber used for highway guard rail posts, to understand the processes that contribute to the total impacts, and to determine how the impacts compare to the primary alternative product, galvanized steel posts. Guard rail posts are the supporting structures for highway guard rails. Transportation engineers, as well as public and regulatory interests, have increasing need to understand the environmental implications of guard rail post selection, in addition to factors such as costs and service performance. This study uses a life cycle inventory (LCI) to catalogue the input and output data from guard rail post manufacture, service life, and disposition, and a life cycle impact assessment (LCIA) to assess anthropogenic and net greenhouse gas (GHG), acidification, smog, ecotoxicity, and eutrophication potentially resulting from life cycle air emissions. Other indicators of interest also are tracked, such as fossil fuel and water use. Comparisons of guard rail post products are made at a functional unit of one post per year of service. This life cycle assessment (LCA) finds that the manufacture, use, and disposition of CCA-treated wood guard rails offers lower fossil fuel use and lower anthropogenic and net GHG emissions, acidification, smog potential, and ecotoxicity environmental impacts than impact indicator values for galvanized steel posts. Water use and eutrophication impact indicator values for CCA-treated guard rail posts are greater than impact indicator values for galvanized steel guard rail posts.
文摘Many studies about the health problems of persons with physical disabilities have been performed, however few studies have focused on the life circumstances of persons with physical disabilities. This study aimed to clarify the relationship between stress and the life circumstances of persons with congenital physical disabilities who must use wheelchairs. The participants were 70 individuals who used the services of care workers employed by welfare service business offices. Participants used wheelchairs. In addition, those participants who used a standard manual wheelchair were not able to operate it alone. Participants were required to answer a two-part questionnaire with questions about factors related to basic lifestyle and stress, and about life factors related to the stress of individuals with physical disabilities. No significant relationship between lifestyle and stress was found in either males or females. Most persons with congenital physical disabilities using wheelchairs had some kind of stress in daily life. In particular, significantly more level of stress was found in females (90%) than that in males (65%). Levels of stress according to life factor differed between males and females. The most dramatic gender difference was that the level of stress caused by the mental or mind factor in females was significantly higher than that in males (p < 0.05). Most persons who must use wheelchairs have stress resulting from daily life, and in particular, females experience more mental stress than males.
文摘BACKGROUND Having a gynecological tumor or undergoing treatment can be a traumatic experience for women,as it affects their self-image and sexual relationships and can lead to psychological reactions.Psychological adjustment following cancer occurrence remains a key issue among the survivors.AIM To examine the current status of quality of life(QoL),anxiety,and depression in patients with gynecological cancer and to analyze the factors associated with it.METHODS Data for 160 patients with gynecological malignancies treated at Shanxi Bethune Hospital from June 2020 to June 2023 were collected and analyzed retrospectively.Patients’QoL was assessed using the European Organization for Research on Treatment of Cancer Quality of Life Questionnaire Core 30 and the Functional Assessment of Cancer Therapy-General Questionnaire.Their emotional status was evaluated using the Self-Rating Anxiety/Depression Scale.The associated factors of anxiety and depression were analyzed.RESULTS The overall QoL score of the patients 6 months after surgery was 76.39±3.63 points.This included low levels of social and emotional function and severe fatigue and pain.The scores for physiological,functional,emotional,social,and family well-being exhibited an upward trend following surgery compared with those before surgery.One month after surgery,some patients experienced anxiety and depression,with an incidence of 18.75%and 18.13%,respectively.Logistic analysis revealed that good sleep was a protective factor against anxiety and depression in patients with gynecological tumors,whereas physical pain was a risk factor.CONCLUSION Patients with gynecological malignancies often experience anxiety and depression.By analyzing the factors that affect patients’QoL,effective nursing measures can be administered.
文摘<strong>Objective:</strong> This review aims to summarize key facets of the Pro Choice and Pro Life perspectives and outline a resolution pathway that minimizes abortion. <strong>Main Results:</strong> Approximately 1.3 billion abortions occurred worldwide from 1990 through 2014. In the United States, more than 61 million abortions were performed between 1973 and 2017. The Pro Choice perspective posits that: 1) A fetus is not a person;therefore, a person is not harmed. 2) Forced childbearing includes significant health and psychological risks to the mother and can exacerbate poverty. Since a person is not harmed and the mother is benefited, abortion is a moral good. From a Judeo-Christian, Pro Life perspective: 1) God creates every person in his image and has a pre-conception life plan for them. 2) God commanded us to be fruitful and multiply and identified children as a blessing. Hence, abortion harms a person and is rebellion against God. <strong>Conclusion: </strong>In working toward a solution, agape love, which is sacrificial and giving, not selfish or condemning, is a good starting point. In that light, the Judeo-Christian community can begin bridging the chasm between the Pro Life and Pro Choice communities by sharing truth in love and helping to meet the material and emotional needs of pregnant women who see no alternative to abortion. Proactive, unconditional love provides the foundation for making the womb a sanctuary for life.
文摘Introduction: Otalgia is not only an indicator of impact of disease but also impairs the daily activities and personal behaviors as is unpleasant and disturbing for the patient. It leads to decrease in functional status up to the complete disability. Nowadays the main focus of physician is to eradicate the disease or the symptoms, leaving behind the humanistic element. In diseased state, the most important point is to assess and improve the quality of life by using multidisciplinary approach. Objective: The objective is to assess the quality of life in patients having otalgia, due to any cause. Methodology: A descriptive cross sectional study was conducted by using modified form of WHOQOL-100 and COQOL. Data was accepted, if CFI was greater than 0.9. Qualitative data were presented as frequency and percentages and quantitative data as mean with standard deviation. ANOVA was used to assess the variations among groups. Change in behavior was assessed by using the Likert scale for each domain of WHOQOL and COQOL by a ten-point scale. Results: Majority of participants about 60.2% were male and were from the age group of 16 - 30 years. Most of the sample population were from lower socioeconomic class. Looking over the WHOQOL-100, higher score represented the higher quality of life. Variation among different socioeconomic status was non-significant for positive attitudes but was highly significant (p = 0.0020) for negative attitudes. Analyzing the COQOL scoring system, higher score reported the worse symptoms. The patient with high COQOL showed strong correlation with poor WHOQOL-100 score that was p value Conclusion: The current study highlights the need of multidisciplinary approach for the better management and improving the quality of life in patients with otalgia.
基金the financial support from the National Natural Science Foundation of China(52207229)the financial support from the China Scholarship Council(202207550010)。
文摘The safe and reliable operation of lithium-ion batteries necessitates the accurate prediction of remaining useful life(RUL).However,this task is challenging due to the diverse ageing mechanisms,various operating conditions,and limited measured signals.Although data-driven methods are perceived as a promising solution,they ignore intrinsic battery physics,leading to compromised accuracy,low efficiency,and low interpretability.In response,this study integrates domain knowledge into deep learning to enhance the RUL prediction performance.We demonstrate accurate RUL prediction using only a single charging curve.First,a generalisable physics-based model is developed to extract ageing-correlated parameters that can describe and explain battery degradation from battery charging data.The parameters inform a deep neural network(DNN)to predict RUL with high accuracy and efficiency.The trained model is validated under 3 types of batteries working under 7 conditions,considering fully charged and partially charged cases.Using data from one cycle only,the proposed method achieves a root mean squared error(RMSE)of 11.42 cycles and a mean absolute relative error(MARE)of 3.19%on average,which are over45%and 44%lower compared to the two state-of-the-art data-driven methods,respectively.Besides its accuracy,the proposed method also outperforms existing methods in terms of efficiency,input burden,and robustness.The inherent relationship between the model parameters and the battery degradation mechanism is further revealed,substantiating the intrinsic superiority of the proposed method.