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Regional Rainfall Damage Functions to Estimate Direct Economic Losses in Rainstorms:A Case Study of the 2016 Extreme Rainfall Event in Hebei Province of China
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作者 Xiaojuan Chen Yifu Xu +2 位作者 Ting Li Jun Wei Jidong Wu 《International Journal of Disaster Risk Science》 SCIE CSCD 2024年第4期508-520,共13页
Developing a regional damage function to quickly estimate direct economic losses(DELs)caused by heavy rain and foods is crucial for providing scientifc supports in efective disaster response and risk reduction.This st... Developing a regional damage function to quickly estimate direct economic losses(DELs)caused by heavy rain and foods is crucial for providing scientifc supports in efective disaster response and risk reduction.This study investigated the factors that infuence regional rainfall-induced damage and developed a calibrated regional rainfall damage function(RDF)using data from the 2016 extreme rainfall event in Hebei Province,China.The analysis revealed that total precipitation,asset value exposure,per capita GDP,and historical geological disaster density at both the township and county levels signifcantly afect regional rainfall-induced damage.The coefcients of the calibrated RDF indicate that doubling the values of these factors leads to varying increases or decreases in rainfall-induced damage.Furthermore,the study demonstrated a spatial scale dependency in the coefcients of the RDF,with increased elasticity values for asset value exposure and per capita GDP at the county level compared to the township level.The fndings emphasize the challenges of applying RDFs across multiple scales and highlight the importance of considering socioeconomic factors in assessing rainfall-induced damage.Despite the limitations and uncertainties of the RDF developed,this study contributes to our understanding of the relationship between physical and socioeconomic factors and rainfall-induced damage.Future research should prioritize enhancing exposure estimation and calibrating RDFs for various types of rainfall-induced disasters to improve model accuracy and performance.The study also acknowledges the variation in RDF performance across diferent physical environments,especially concerning geological disasters and slope stability. 展开更多
关键词 Regional rainfall damage function loss attribution Direct economic losses Rainfall intensity Asset value VULNERABILITY
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Assessing Human-Wildlife Conflict in the Periphery of Loango National Park in Gabon
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作者 Mbani Cynthia Axelle Eugénie N’Safou Abubakar Ali Shidiki Ngankam Martin Tchamba 《Open Journal of Forestry》 2024年第3期297-312,共16页
Human-Wildlife Conflict in Gabon is a reality occurring in almost all protected areas in the country. These conflicts create real threats both for the survival of wildlife species and of human beings. This study was c... Human-Wildlife Conflict in Gabon is a reality occurring in almost all protected areas in the country. These conflicts create real threats both for the survival of wildlife species and of human beings. This study was carried out at the periphery of Loango National Park in Gabon. This area is particular of seeing elephants wandering around villages. Respondents for the study were drawn from a wide range of stakeholders (State administrators, farmers and NGOs). Data was collected through administration of structured questionnaires and interview guide on the;socio-economic activities. Crops produced/destroyed. Animals are involved and economic loss is incurred due to conflicts. Data was analysed using SPSS version 16 and Kobo tool box. For qualitative data chi-square, descriptive statistic and linear regression model were also used. The results of the study showed that the elephants account for (60.1%) of crop destroyed followed by Ungulates (30.4%) and lastly by rodents (0.9%). The economic damage caused by the wildlife to crops valued at 72,084 USD in the zone in 2022. An urgent solution to this conflict is needed because the consequences are visible as well as the illegal repression by communities that have led to poisoning and killing of wildlife in the study area. 展开更多
关键词 Human-Wildlife Conflict Protected Areas Crop Damage Crop losses Loango National Park
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Theory and Application of Loss of Life Risk Analysis for Dam Break 被引量:2
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作者 孙月峰 钟登华 +1 位作者 李明超 李颖 《Transactions of Tianjin University》 EI CAS 2010年第5期383-387,共5页
The loss of life risk evaluation model for dam break is built in this paper.By using an improved Monte Carlo method,the overtopping probability induced by concurrent flood and wind is calculated,and the Latin Hypercub... The loss of life risk evaluation model for dam break is built in this paper.By using an improved Monte Carlo method,the overtopping probability induced by concurrent flood and wind is calculated,and the Latin Hypercube Sampling is used to generate random numbers.The Graham method is used to calculate the loss of life resulting from dam failure.With Dongwushi reservoir located at Hebei Province taken as an example,the overtopping probability induced by concurrent flood and wind is calculated as 4.77×10-6.Los... 展开更多
关键词 overtopping probability loss of life risk risk assessment dam safety management
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Ms 6.5 Earthquake Occurred in Ludian County of Yunnan Province,China,Although Forecast Issued before the Earthquake,Life Casualties and Property Losses were Still Caused Significant
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第4期1334-1336,共3页
1 Geography Location At 16:30 on August 3rd, 2014, Ludian County, Zhaotong City, Yunnan Province (27.1°N, 103.3°E) was hit by Ms 6.5 earthquake, with the maximum intensity is 9 and epicenter depth is aro... 1 Geography Location At 16:30 on August 3rd, 2014, Ludian County, Zhaotong City, Yunnan Province (27.1°N, 103.3°E) was hit by Ms 6.5 earthquake, with the maximum intensity is 9 and epicenter depth is around 12 km (Figs. 1 and 2). 展开更多
关键词 Ms 6.5 Earthquake Occurred in Ludian County of Yunnan Province China Although forecast Issued before the Earthquake life Casualties and Property losses were Still Caused Significant
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Impact of cancer diagnosis on life expectancy by area-level socioeconomic groups in New South Wales, Australia: a population-based study
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作者 Md Mijanur Rahman Michael David +5 位作者 David Goldsbury Karen Canfell Kou Kou Paramita Dasgupta Peter Baade Xue Qin Yu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第8期692-702,共11页
Objective: Improvement in cancer survival over recent decades has not been accompanied by a narrowing of socioeconomic disparities. This study aimed to quantify the loss of life expectancy(LOLE) resulting from a cance... Objective: Improvement in cancer survival over recent decades has not been accompanied by a narrowing of socioeconomic disparities. This study aimed to quantify the loss of life expectancy(LOLE) resulting from a cancer diagnosis and examine disparities in LOLE based on area-level socioeconomic status(SES).Methods: Data were collected for all people between 50 and 89 years of age who were diagnosed with cancer, registered in the NSW Cancer Registry between 2001 and 2019, and underwent mortality follow-up evaluations until December 2020. Flexible parametric survival models were fitted to estimate the LOLE by gender and area-level SES for 12 common cancers.Results: Of 422,680 people with cancer, 24% and 18% lived in the most and least disadvantaged areas, respectively. Patients from the most disadvantaged areas had a significantly greater average LOLE than patients from the least disadvantaged areas for cancers with high survival rates, including prostate [2.9 years(95% CI: 2.5±3.2 years) vs. 1.6 years(95% CI: 1.3±1.9 years)] and breast cancer [1.6 years(95% CI: 1.4±1.8 years) vs. 1.2 years(95% CI: 1.0±1.4 years)]. The highest average LOLE occurred in males residing in the most disadvantaged areas with pancreatic [16.5 years(95% CI: 16.1±16.8 years) vs. 16.2 years(95% CI: 15.7±16.7 years)] and liver cancer [15.5 years(95% CI: 15.0±16.0 years) vs. 14.7 years(95% CI: 14.0±15.5 years)]. Females residing in the least disadvantaged areas with thyroid cancer [0.9 years(95% CI: 0.4±1.4 years) vs. 0.6 years(95% CI: 0.2±1.0 years)] or melanoma [0.9 years(95% CI: 0.8±1.1 years) vs. 0.7 years(95% CI: 0.5±0.8 years)] had the lowest average LOLE.Conclusions: Patients from the most disadvantaged areas had the highest LOLE with SES-based differences greatest for patients diagnosed with cancer at an early stage or cancers with higher survival rates, suggesting the need to prioritise early detection and reduce treatment-related barriers and survivorship challenges to improve life expectancy. 展开更多
关键词 Cancer diagnosis life expectancy loss of life expectancy area-level socioeconomic status flexible parametric model
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Characterization,identification and life prediction of acoustic emission signals of tensile damage for HSR gearbox housing material
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作者 Ai Yibo Zhang Yuanyuan +1 位作者 Cui Hao Zhang Weidong 《Railway Sciences》 2023年第2期225-242,共18页
Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional... Purpose-This study aims to ensure the operation safety of high speed trains,it is necessary to carry out nondestructive monitoring of the tensile damage of the gearbox housing material in rail time,yet the traditional tests of mechanical property can hardly meet this requirement.Design/methodology/approach-In this study the acoustic emission(AE)technology is applied in the tensile tests of the gearbox housing material of an high-speed rail(HSR)train,during which the acoustic signatures are acquired for parameter analysis.Afterward,the support vector machine(SVM)classifier is introduced to identify and classify the characteristic parameters extracted,on which basis the SVM is improved and the weighted support vector machine(WSVM)method is applied to effectively reduce the misidentification of the SVM classifier.Through the study of the law of relations between the characteristic values and the tensile life,a degradation model of the gearbox housing material amid tensile is built.Findings-The results show that the growth rate of the logarithmic hit count of AE signals and that of logarithmic amplitude can well characterize the stage of the material tensile process,and the WSVM method can improve the classification accuracy of the imbalanced data to above 94%.The degradation model built can identify the damage occurred to the HSR gearbox housing material amid the tensile process and predict the service life remains.Originality/value-The results of this study provide new concepts for the life prediction of tensile samples,and more further tests should be conducted to verify the conclusion of this research. 展开更多
关键词 HSR gearbox housing Damage identification Acoustic emission technology Support vector machine WEIGHTED life prediction
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Predictive factors for body weight loss and its impact on quality of life following gastrectomy 被引量:3
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作者 Kazuaki Tanabe Masazumi Takahashi +7 位作者 Takashi Urushihara Yoichi Nakamura Makoto Yamada Sang-Woong Lee Shinnosuke Tanaka Akira Miki Masami Ikeda Koji Nakada 《World Journal of Gastroenterology》 SCIE CAS 2017年第26期4823-4830,共8页
To determine the predictive factors and impact of body weight loss on postgastrectomy quality of life (QOL). METHODSWe applied the newly developed integrated questionnaire postgastrectomy syndrome assessment scale-45,... To determine the predictive factors and impact of body weight loss on postgastrectomy quality of life (QOL). METHODSWe applied the newly developed integrated questionnaire postgastrectomy syndrome assessment scale-45, which consists of 45 items including those from the Short Form-8 and Gastrointestinal Symptom Rating Scale instruments, in addition to 22 newly selected items. Between July 2009 and December 2010, completed questionnaires were received from 2520 patients with curative resection at 1 year or more after having undergone one of six types of gastrectomy for Stage I gastric cancer at one of 52 participating institutions. Of those, we analyzed 1777 eligible questionnaires from patients who underwent total gastrectomy with Roux-en-Y procedure (TGRY) or distal gastrectomy with Billroth-I (DGBI) or Roux-en-Y (DGRY) procedures. RESULTSA total of 393, 475 and 909 patients underwent TGRY, DGRY, and DGBI, respectively. The mean age of patients was 62.1 ± 9.2 years. The mean time interval between surgery and retrieval of the questionnaires was 37.0 ± 26.8 mo. On multiple regression analysis, higher preoperative body mass index, total gastrectomy, and female sex, in that order, were independent predictors of greater body weight loss after gastrectomy. There was a significant difference in the degree of weight loss (P < 0.001) among groups stratified according to preoperative body mass index (< 18.5, 18.5-25 and > 25 kg/m<sup>2</sup>). Multiple linear regression analysis identified lower postoperative body mass index, rather than greater body weight loss postoperatively, as a certain factor for worse QOL (P < 0.0001) after gastrectomy, but the influence of both such factors on QOL was relatively small (R<sup>2</sup>, 0.028-0.080). CONCLUSIONWhile it is certainly important to maintain adequate body weight after gastrectomy, the impact of body weight loss on QOL is unexpectedly small. 展开更多
关键词 Quality of life GASTRECTOMY Weight loss Postgastrectomy syndrome assessment scale-45
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Remedies for loss and damage caused by climate change from the dimension of climate justice
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作者 Mingde Cao Qi Wang Yu Cheng 《Chinese Journal of Population,Resources and Environment》 2016年第4期253-261,共9页
Adverse consequences to the ecological system and human health caused by impacts potentially attributable to climate change have already drawn great and widespread concern of many scientists and international organiza... Adverse consequences to the ecological system and human health caused by impacts potentially attributable to climate change have already drawn great and widespread concern of many scientists and international organizations.However,we still have a hard time determining exactly the impact of climate change on the environment or the damage that climate change inflicts on countries comprising small islands or low-lying lands in light of today's science and technology.The progress for dealing with the issue of loss and damage has been struggling for a long time from the beginning to the present.In this paper,the author begins by summarizing talks on the concept and the positions of commentators.The author is proposing that the development of future climate negotiations and rule-making process be based on global climate justice as a standard for measuring value.Also,the author proposes that a holistic view of climate justice be established.Generally,three aspects of climate justice can be derived.First,the dimension of human rights protection shows that protection of fundamental human rights is a logical precondition if small-island and low-lying countries are able to achieve climate justice.Second,the definite and traditional concepts of distributive justice and corrective justice hold the view that the principle of common but differentiated responsibilities should be upheld as a basic standard of allocating rights and duties associated with climate change.Third,climate justice requires that any state follow the "no-harm principle," which is regarded as an international customary rule.According to the principle,the obligation of states to prevent the use of their territory for causing trans-boundary harm to the environment shall be a violation of state responsibility,which incurs international punishment.Then we put forward three remedial approaches in light of climate justice,including the approach of State Responsibility(SR) based on the principles and rules of international human rights law and international environmental law.Based on clear rules,the judge can determine whether the damaging behavior or the damage perpetrated by a state party constitutes a state responsibility.The International Environmental Regulation(IEB),which means solving the problems within the framework established by the Conventions on Climate Change,takes advantage of the market mechanisms and incentives such as fund and insurance support system to relieve or compensate the loss and damage.International Environmental Dispute Settlement Mechanism(IEDSM),which includes the means such as consultations,negotiations,nonmandatory ways and international arbitration,international judicial ways to solve these disputes,functions as a procedural safeguard.As an active promoter of global climate governance,China should no doubt stand by the principle of Common But Differentiated Responsibility(CBDR) and take it as a basis for negotiations,actively strengthen the work of South-South cooperation,fulfill her international climate commitments without reservation,vigorously develop a low-carbon economy,and actively promote international negotiations on the subject of loss and damage. 展开更多
关键词 loss and damage climate justice principle of CBDR state responsibility international environmental regulation
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Life Loss Estimation Based on Dam-Break Flood Uncertainties and Lack of Information in Mountainous Regions of Western China 被引量:1
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作者 Chao Wang Sherong Zhang +2 位作者 Yaosheng Tan Fei Pan Lei Yan 《Transactions of Tianjin University》 EI CAS 2017年第4期370-379,共10页
Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly ... Compared with urban floods, dam-break floods are associated with greater uncertainties, including variable dam-break modes and hydrological characteristics, so conventional flood estimation methods cannot be directly applied in the estimation of dam-break flood loss. In particular, there is scant information regarding the conditions of affected area and hydrological characteristics in southwest China. In this paper, we introduce an integrated model for estimating flood loss that is adapted to the mountainous regions of southwestern China in light of the relative lack of available information. This model has three major components: a basic information model, a dam-routed flood propagation simulation model, and a loss estimation model. We established the basic information model despite the relative lack of available information using 3S technology [remote sensing (RS); geographical information system (GIS); global positioning system (GPS)], data mining technology, and statistical analysis techniques. Our dam-routed flood propagation simulation model consists of major hydrologic processes and their governing equations for flow propagation, which we solve using finite-difference schemes. In this model, the flood propagation area is divided into grids and each grid is determined by the characteristic parameters obtained from the propagation simulation. We present a case study of the Lianghekou hydropower station in Sichuan Province, China to illustrate the practical application of this integrated model for life loss estimation. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 DAMS ESTIMATION Finite difference method Flood damage Floods Geographic information systems Global positioning system Information theory Remote sensing
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Influence of Tooth Loss and Unmet Treatment Needs on the Social Aspects of Quality of Life and Self-esteem in Adolescents
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作者 Pavlovic Maja Matijevic Dusanka +3 位作者 Vukovic Branislava Mileusnic Ivan Gajic Milica Jevremovic Ana 《Journal of Pharmacy and Pharmacology》 2019年第1期22-31,共10页
Adolescence represents specific period of life and development,when young person is going through physical,emotional and mental changes,risking poor general and oral health outcome that might affect quality of life.Ne... Adolescence represents specific period of life and development,when young person is going through physical,emotional and mental changes,risking poor general and oral health outcome that might affect quality of life.Negative effects of poor oral health are various:difficulties with speaking and eating,pain and malfunction.This might cause emotional and mental problems,leading to avoidance of speaking,smiling and socializing with friends.Cross-sectional study included 234 participants(15-16 years old).The research instruments used in the study were questionnaire and clinical examination.Questionnaire referred to socio-demographic characteristics of participants,their oral and general health related habits,self-evaluation of confidence and successfulness and effect of oral impacts on daily performances.Clinical examination was used to determine dental status in terms of tooth loss,need for prosthodontic rehabilitation and presence of dental malocclusion.Results:24.6%(58)of adolescents had at least one tooth missing.Significant difference between the genders was obtained,as 32.5%girls had at least one tooth extracted compared to 8.1%of boys.Normative need for prosthodontic rehabilitation was present in 22.0%of subjects.Dental problems negatively affected their sleep and emotions(14.4%and 10.2%few times in period of one month).Data analyses pointed one correlation between extracted teeth and psychosocial aspect of participants'life(difficulties and embarrassment when smiling,talking and spending time with friends,emotional problems).Unmet normative need for prosthodonic or orthodontic treatment affected participants'ability to sleep and relax.Percentage of adolescents with extracted teeth was high,as well as normative treatment need for prosthodontic rehabilitation.Poor dental status affected quality of life of adolescents,especially emotional and mental well-being.Dental service should provide sufficient information to adolescents about prevention of tooth loss and consequences of teeth extraction,not only within masticatory function but also concerning oral health related quality of life. 展开更多
关键词 ADOLESCENT TOOTH loss NORMATIVE TREATMENTS need quality of life
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The Impact of Hearing Loss on Health: Interprofessional Guidance for Health and Primary Care Providers (PCPs)
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作者 Abbey L.Berg Ellen D.Mandel 《Journal of International Education and Practice》 2020年第1期35-38,共4页
In the United States, approximately one in eight (13 percent, or 30 million)individuals aged 12 years or older has bilateral hearing loss. Whenunaddressed and untreated, hearing loss is associated with and contributes... In the United States, approximately one in eight (13 percent, or 30 million)individuals aged 12 years or older has bilateral hearing loss. Whenunaddressed and untreated, hearing loss is associated with and contributesto other significant health issues;specifically, social isolation, depression,stress, and anxiety, incidental falls, dementia and impaired cognition, andreduced quality of life. This is a public health concern. Health and primarycare providers are in a unique position to have a positive impact by probingthe hearing of the patients they see, providing information, and makingappropriate referrals to reduce deleterious effects when this impairmentoccurs.Abbreviations: Hertz (Hz);High frequency hearing loss (HFHL);Personallistening devices (PLDs);Sensorineural hearing loss (SNHL)Format: Small group discussion, classroom and clinical practicum settings.Target audience: The student and practicing health professions (e.g.occupational and physical therapy, psychologists, physician assistants,nursing, and medical) involved and the relevant point in their training andpractice. 展开更多
关键词 Hearing loss Quality of life Public health INTERPRofESSIONAL
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Model of Probabilistic Prediction for Life Loss
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作者 Jin Xueshen,Liu Yunqing,Hu Mingqing,Liu Zhihui,Nie Lei,and Zhang FengzhiSeismological Bureau of Hebei Province,Shijiazhuang 050021,China Jianghan University,Wuhan 430010,China 《Earthquake Research in China》 1998年第1期37-45,共9页
Based on discussion of the reasonableness of the seismic destruction described by using the death degree,the probabilistic curves of the different death degrees with different future times in several regions on the Ch... Based on discussion of the reasonableness of the seismic destruction described by using the death degree,the probabilistic curves of the different death degrees with different future times in several regions on the Chinese mainland have been obtained by applying the probabilistic model,which is in accord with present seismic destruction data and related data.The historical data of the life loss have been processed with the dynamic system model.Finally,the results from two kinds of data have been analyzed and discussed. 展开更多
关键词 life loss PROBABILITY PREDICTION model.
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Measuring economic loss caused by ecological damages: a case study of China's forest ecosystem in 2005
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作者 CAO Ying 《Ecological Economy》 2010年第1期45-50,共6页
At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key ... At present about 60% of ecosystem has been damaged and degraded severely, resulting in enormous ecological loss globally. The essential cause is the irrational utilization of ecosystem by humankind, so it is tire key to changing improper environmental performance of humankind so as to prevent ecosystem from being damaged The quantitative valuation on the loss of ecological damage is an effective tool to guide human eco-environmental performance. In this paper, the concepts related to the valuation on ecological damage cost are introduced," uncertainties that might arise in the valuation on the loss of ecological damage such as area coverage of valuation, ecological damage quantity, borders of ecological damage cost and data support are analyzed and the valuation approaches for the loss of ecological damage are also discussed As a case study, the economic losses of ecological damage of forest in 2005 in China are valuated. 展开更多
关键词 Ecosystem services and functions: Ecological damage Valuation on economic loss Uneertainty Valuation approaches forEST
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Master Curve Method of Cumulative Damage for Prediction of Service Life
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作者 沈庭芳 赵伯华 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期109-113,共5页
Aim To study the theory and method for the prediction of service life of solid rocket propellant grain. Methods With the aid of discontiguous diagnostic technology and method of accumulated damage using accelerated... Aim To study the theory and method for the prediction of service life of solid rocket propellant grain. Methods With the aid of discontiguous diagnostic technology and method of accumulated damage using accelerated aging or heat air oven, the aging isotherms for void content versus aging time were determined. According to the principle of time temperature equivalence the viscoelastic master curve for the prediction of service life were obtained. Results and Conclusion The service life of HMX CMDB solid rocket propellant grain were obtained. Because the critical storage life is measured, the accuracy of predicting the service life of the grain has been increased greatly. 展开更多
关键词 void content thermal aging cumulative damage service life
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Impact of intensity and loss assessment following the great Wenchuan Earthquake 被引量:15
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作者 Yuan Yifan 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第3期247-254,共8页
The great Wenchuan Earthquake occurred on May 12, 2008 in the Sichuan Province of China, and had a magnitude of 8.0. It is the most serious earthquake disaster in China since the great Tangshan Earthquake (Ms=7.8, Ju... The great Wenchuan Earthquake occurred on May 12, 2008 in the Sichuan Province of China, and had a magnitude of 8.0. It is the most serious earthquake disaster in China since the great Tangshan Earthquake (Ms=7.8, July 28, 1976). According to official reports, there were 69,225 deaths, 379,640 injuries and 17,939 missing as of Aug. 11, 2008. The China Earthquake Administration quickly sent hundreds of experts to the field immediately after the event, to investigate the damage and assess the economic losses. This paper emphasizes the impact of seismic intensity and presents a preliminary loss assessment. A brief description of the geological features of the affected region is provided, followed by a summary of the earthquake damage. An isoseismal map is developed that shows that the high intensity region is distributed like a belt around the seimogenic fault, and that the epicentral intensity reached Ⅺ (Chinese Intensity Scale, similar to the Modified Mercalli Scale). The direct economic loss resulting from the earthquake is 692 billions RMB (about 100 billions US$). 展开更多
关键词 Wenchuan Earthquake isoseismal map earthquake intensity earthquake damage direct loss
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Modeling and simulation of bullet-barrel interaction process for the damaged gun barrel 被引量:9
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作者 Chao Shen Ke-dong Zhou +1 位作者 Ye Lu Jun-song Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第6期972-986,共15页
In this paper,the influences of bore damage on the bullet-barrel interaction process and the mechanism of how bore damage results in the end of a machine gun barrel’s service life were studied,which had seldom been p... In this paper,the influences of bore damage on the bullet-barrel interaction process and the mechanism of how bore damage results in the end of a machine gun barrel’s service life were studied,which had seldom been paid attention to in the past several decades.A novel finite element mesh generation method for the damaged barrel and a new transient coupled thermo-mechanical finite element(FE)model,which were based on the damage data obtained through barrel life tests,were developed to simulate the interior ballistics process of a coupled bullet-barrel system.Additionally,user subroutine VUAMP was developed in the FE model in order to take the bullet base pressure brought by propellant gas into account.Good consistency between the simulation results and the experimental results verified the preciseness of the proposed mesh generation method and the FE model.The simulation results show that the increase of bullet’s initial disturbance at the muzzle and the variation of its surface morphology caused by bore damage are primarily responsible for the life end of this 12.7 mm machine gun barrel. 展开更多
关键词 Barrel life tests Real bore damage Interior ballistics performance Initial disturbance Finite element method
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Fatigue Life Prediction under Service Load Considering Strengthening Effect of Loads below Fatigue Limit 被引量:5
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作者 ZHAO Lihui ZHENG Songlin FENG Jinzhi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1178-1185,共8页
Lightweight design requires an accurate life prediction for structures and components under service loading histories. However, predicted life with the existing methods seems too conservative in some cases, leading to... Lightweight design requires an accurate life prediction for structures and components under service loading histories. However, predicted life with the existing methods seems too conservative in some cases, leading to a heavy structure. Because these methods are established on the basis that load cycles would only cause fatigue damage, ignore the strengthening effect of loads. Based on Palmgren-Miner Rule (PMR), this paper introduces a new method for fatigue life prediction under service loadings by taking into account the strengthening effect of loads below the fatigue limit. In this method, the service loadings are classified into three categories: damaging load, strengthening load and none-effect load, and the process for fatigue life prediction is divided into two stages: stage I and stage II, according to the best strengthening number of cycles. During stage I, fatigue damage is calculated considering both the strengthening and damaging effect of load cycles. While during stage II, only the damaging effect is considered. To validate this method, fatigue lives of automobile half shaft and torsion beam rear axle are calculated based on the new method and traditional methods, such as PMR and Modified Miner Rule (MMR), and fatigue tests of the two components are conducted under service loading histories. The tests results show that the percentage errors of the predicted life with the new method to mean life of tests for the two components are –3.78% and –1.76% separately, much lesser than that with PMR and MMR. By considering the strengthening effect of loads below the fatigue limit, the new method can significantly improve the accuracy for fatigue life prediction. Thus lightweight design can be fully realized in the design stage. 展开更多
关键词 fatigue life fatigue damage service loading strengthening effect load below the fatigue limit
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TWO METHODS FOR ASSESSMENT OF RESIDUAL LIFE OF HK-40 FURNACE TUBES 被引量:4
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作者 F.Z. Shen. G.X. Ma and X. Ling Nanjing University of Chemical Technology, Nanjing 210009, China X. Yang Jing Ling Petrochemical Corporation, Nanjing 210046, China X.Z. Zhang, J. Ruan and Y. Lu Lutianhua Group Incorporated, Luzhou 646300, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第1期108-115,共8页
Two methods for predicting residual life of high temperature furnace tubes are studied. One is testanalysis method that is mainly based on the creep rupture tests on postservice specimens. Specimens were taken from th... Two methods for predicting residual life of high temperature furnace tubes are studied. One is testanalysis method that is mainly based on the creep rupture tests on postservice specimens. Specimens were taken from the tubes, which had been in service for different times. KachanovRobinsons damage summation concept is employed, however with a modified factor K(ts) to account for prior damage in the specimens. If the foregone total life corresponds with real condition, all of the test data modified by K(ts) should be distributed uniformly nearby the master curve of the new material. The other iscomputer simulation method that considers all of the operating conditions that influence the life. The finite element method (FEM) with iterative calculation is used in the analysis. The variation rates of critical damage element along the wall thickness are determined as a function of the service temperature and current damage. A special program designed based on the method predicts well the residual life of furnace tubes, so long as the maximum depth of critical damage in radius direction of tubes has been detected by ultrasonic techniques. 展开更多
关键词 residual life ASSESSMENT HK-40 damage creep furnace tube
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Revised damage evolution equation for high cycle fatigue life prediction of aluminum alloy LC4 under uniaxial loading 被引量:3
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作者 Zhixin ZHAN Weiping HU +1 位作者 Miao ZHANG Qingchun MENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第9期1185-1196,共12页
The fatigue life prediction for components is a difficult task since many factors can affect the final fatigue life. Based on the damage evolution equation of Lemaitre and Desmorat, a revised two-scale damage evolutio... The fatigue life prediction for components is a difficult task since many factors can affect the final fatigue life. Based on the damage evolution equation of Lemaitre and Desmorat, a revised two-scale damage evolution equation for high cycle fatigue is presented according to the experimental data, in which factors such as the stress amplitude and mean stress are taken into account. Then, a method is proposed to obtain the material parameters of the revised equation from the present fatigue experimental data. Finally, with the utilization of the ANSYS parametric design language (APDL) on the ANSYS platform, the coupling effect between the fatigue damage of materials and the stress distribution in structures is taken into account, and the fatigue life of specimens is predicted. The outcome shows that the numerical prediction is in accord with the experimental results, indicating that the revised two-scale damage evolution model can be well applied for the high cycle fatigue life prediction under uniaxial loading. 展开更多
关键词 fatigue damage model continuum damage mechanics fatigue life highcycle fatigue finite element method
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Heavy soil drying during mid-to-late grain filling stage of the main crop to reduce yield loss of the ratoon crop in a mechanized rice ratooning system 被引量:6
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作者 Chang Zheng Yuechao Wang +4 位作者 Shen Yuan Sen Xiao Yating Sun Jianliang Huang Shaobing Peng 《The Crop Journal》 SCIE CSCD 2022年第1期280-285,共6页
Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning technology.Soil drying before t... Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning technology.Soil drying before the harvest of the main crop has been proposed to overcome this problem.The objective of this study was to determine the effect of soil drying during the mid-to-late grain filling stage of the main crop on grain yield of the ratoon crop in a mechanized rice ratooning system.Field experiments were conducted to compare Y_(Loss) between light(LD) and heavy(HD) soil drying treatments in Hubei province,central China in 2017 and 2018.Y_(Loss) was calculated as the percentage of yield reduction in the ratoon crop with the main crop harvested mechanically,relative to the grain yield of the ratoon crop with the main crop harvested manually.In comparison with LD,soil hardness was increased by 42.8%-84.7% in HD at the 5-20 cm soil depth at maturity of the main crop.Soil hardness at 5 and 10 cm depths reached respectively 4.05 and 7.07 kg cm^(-2) in HD.Soil drying treatment did not significantly affect the grain yield of the main crop.Under mechanical harvesting of the main crop,HD increased the grain yield of the ratoon crop by 9.4% relative to LD.Consequently,Y_(Loss) was only 3.4% in HD,in contrast to 16.3% in LD.The differences in grain yield and Y_(Loos) between the two soil drying treatments were explained mainly by panicles m^(-2),which was increased significantly by HD in the track zone of the ratoon crop compared with LD.These results suggest that heavy soil drying practice during the mid-to-late grain filling stage of the main crop is effective for reducing Y_(Loss) of the ratoon crop in a mechanized rice ratooning system. 展开更多
关键词 Crushing damage Mechanical harvesting Ratoon rice Soil drying Yield loss
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