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A WEIGHTED RESIDUAL METHOD FOR ELASTIC-PLASTIC ANALYSIS NEAR A CRACK TIP AND THE CALCULATION OF THE PLASTIC STRESS INTENSITY FACTORS
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作者 张宁生 赵学仁 薛大为 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第12期1123-1134,共12页
In this paper, a weighted residual method for the elastic-plastic analysis near a crack tip is systematically given by taking the model of power-law hardening under plane strain condition as a sample. The elastic-plas... In this paper, a weighted residual method for the elastic-plastic analysis near a crack tip is systematically given by taking the model of power-law hardening under plane strain condition as a sample. The elastic-plastic solutions of the crack lip field and an approach based on the superposition of the nonlinear finite element method on the complete solution in the whole crack body field, to calculate the plastic stress intensity factors, are also developed. Therefore, a complete analvsis based on the calculation both for the crack tip field and for the whole crack body field is provided. 展开更多
关键词 fracture mechanics stress intensity factor weighted residual method crack tip field
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Retrieval Single-Doppler Radar Wind with Variational Assimilation Method-Part I: Objective Selection of Functional Weighting Factors 被引量:5
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作者 魏鸣 党人庆 葛文忠 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1998年第4期123-138,共16页
In variational problem, the selection of functional weighting factors (FWF) is one of the key points for discussing many relevant studies. To overcome arbitrariness and subjectivity of the empirical selecting methods ... In variational problem, the selection of functional weighting factors (FWF) is one of the key points for discussing many relevant studies. To overcome arbitrariness and subjectivity of the empirical selecting methods used widely at present, this paper tries to put forward an optimal objective selecting method of FWF. The focus of the study is on the weighting factors optimal selection in the variation retrieval single-Doppler radar wind field with the simple adjoint models. Weighting factors in the meaning of minimal variance are calculated out with the matrix theory and the finite difference method of partial differential equation. Experiments show that the result is more objective comparing with the factors obtained with the empirical method. 展开更多
关键词 Variation weighting factor Minimum variance Objective selection
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New weighting factors assignment of evidence theorybased one vidence distance 被引量:3
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作者 ChenLiangzhou ShiWenkang DuFeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期273-278,共6页
Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict ... Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict information exists. Based on the analysis of some modified methods, Assigning the weighting factors according to the intrinsic characteristics of the existing evidence sources is proposed, which is determined on the evidence distance theory. From the numerical examples, the proposed method provides a reasonable result with good convergence efficiency. In addition, the new rule retrieves to the Yager's formula when all the evidence sources contradict to each other completely. 展开更多
关键词 evidence theory rule of combination weighting factors evidence distance.
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Evaluation of soil erosion vulnerability in Hubei Province of China using RUSLE model and combination weighting method
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作者 YANG Yanpan TIAN Pei +3 位作者 JIA Tinghui WANG Fei YANG Yang HUANG Jianwu 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3318-3336,共19页
Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a not... Soil erosion has been recognized as a critical environmental issue worldwide.While previous studies have primarily focused on watershed-scale soil erosion vulnerability from a natural factor perspective,there is a notable gap in understanding the intricate interplay between natural and socio-economic factors,especially in the context of spatial heterogeneity and nonlinear impacts of human-land interactions.To address this,our study evaluates the soil erosion vulnerability at a provincial scale,taking Hubei Province as a case study to explore the combined effects of natural and socio-economic factors.We developed an evaluation index system based on 15 indicators of soil erosion vulnerability:exposure,sensitivity,and adaptability.In addition,the combination weighting method was applied to determine index weights,and the spatial interaction was analyzed using spatial autocorrelation,geographical temporally weighted regression and geographical detector.The results showed an overall decreasing soil erosion intensity in Hubei Province during 2000 and 2020.The soil erosion vulnerability increased before 2000 and then.The areas with high soil erosion vulnerability were mainly confined in the central and southern regions of Hubei Province(Xiantao,Tianmen,Qianjiang and Ezhou)with obvious spatial aggregation that intensified over time.Natural factors(habitat quality index)had negative impacts on soil erosion vulnerability,whereas socio-economic factors(population density)showed substantial spatial variability in their influences.There was a positive correlation between soil erosion vulnerability and erosion intensity,with the correlation coefficients ranging from-0.41 and 0.93.The increase of slope was found to enhance the positive correlation between soil erosion vulnerability and intensity. 展开更多
关键词 Soil erosion vulnerability RUSLE model Combination weighting method Driving factors Spatial heterogeneity
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Geographically and Temporally Weighted Regression in Assessing Dengue Fever Spread Factors in Yunnan Border Regions
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作者 ZHU Xiao Xiang WANG Song Wang +3 位作者 LI Yan Fei ZHANG Ye Wu SU Xue Mei ZHAO Xiao Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期511-520,共10页
Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-tempor... Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-temporal variability of these factors in border regions.Methods We conducted a descriptive analysis of dengue fever’s temporal-spatial distribution in Yunnan border areas.Utilizing annual data from 2013 to 2019,with each county in the Yunnan border serving as a spatial unit,we constructed a GTWR model to investigate the determinants of dengue fever and their spatio-temporal heterogeneity in this region.Results The GTWR model,proving more effective than Ordinary Least Squares(OLS)analysis,identified significant spatial and temporal heterogeneity in factors influencing dengue fever’s spread along the Yunnan border.Notably,the GTWR model revealed a substantial variation in the relationship between indigenous dengue fever incidence,meteorological variables,and imported cases across different counties.Conclusion In the Yunnan border areas,local dengue incidence is affected by temperature,humidity,precipitation,wind speed,and imported cases,with these factors’influence exhibiting notable spatial and temporal variation. 展开更多
关键词 Dengue fever Meteorological factor Geographically and temporally weighted regression
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A methodological approach for weighting factors in land suitability assessment: a tool for facilitating spatial planning 被引量:1
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作者 Neetu KAPOOR Minakshi JAIN Vijay Kumar BANSAL 《Journal of Mountain Science》 SCIE CSCD 2020年第3期724-739,共16页
The increasing demand for infrastructural facilities in hill areas needs efficient spatial planning at the local level through land suitability assessment,which is influenced by a number of factors. There has been lit... The increasing demand for infrastructural facilities in hill areas needs efficient spatial planning at the local level through land suitability assessment,which is influenced by a number of factors. There has been little systematic empirical work for identification and evaluation of the factors affecting spatial planning decisions in hill areas. The present study focuses on identifying the critical factors for land suitability assessment at the local level in hill areas and determining their percentage influence, which has been done in two stages. In the first stage, the comprehensive list of 21 factors from the reported literature was prepared which was further condensed to the critical factors. In the second stage, the percentage influence of the critical factors was calculated by analyzing the experts’ opinions collected through a questionnaire survey. Analytic Hierarchy Process(AHP) was used for the analysis of the questionnaire for weighting the critical factors. The slope was identified with the highest weight followed by aspect, surface runoff, elevation, and vegetation,whereas groundwater table, existing utilities,accessibility, soil type, and land use have comparatively less weights. The results of the study were used for the identification of locations for builtup facilities of an educational campus located in hill areas of Himachal Pradesh, India. 展开更多
关键词 factor identification HILL areas ANALYTIC HIERARCHY process INDIA weightED OVERLAY
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Systemic Inflammation Response Index and weight loss as prognostic factors in metastatic pancreatic cancer: A concept study from the PANTHEIA-SEOM trial
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作者 Vilma Pacheco-Barcia Sara Custodio-Cabello +7 位作者 Fatima Carrasco-Valero Magda Palka-Kotlowska Axel Mariño-Mendez Alberto Carmona-Bayonas Javier Gallego A J Muñoz Martín Paula Jimenez-Fonseca Luis Cabezon-Gutierrez 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期386-397,共12页
BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AI... BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AIM To study the prognostic significance of SIRI and weight loss in metastatic pancreatic cancer.METHODS The PANTHEIA-Spanish Society of Medical Oncology(SEOM)study is a multicentric(16 Spanish hospitals),observational,longitudinal,non-interventional initiative,promoted by the SEOM Real World-Evidence work group.This pilot study sought to analyze the association between weight loss and inflammatory status as defined by SIRI.The cohort stems from a proof-of-concept pilot study conducted at one of the coordinating centers.Patients with pathologically confirmed metastatic pancreatic adenocarcinoma,treated from January 2020 to January 2023,were included.The index was calculated using the product of neutrophil and monocyte counts,divided by lymphocyte counts,obtained within 15 days before initiation chemotherapy.This study evaluated associations between overall survival(OS),SIRI and weight loss.RESULTS A total of 50 patients were included.66%of these patients were male and the median age was 66 years.Metastasis sites:36%liver,12%peritoneal carcinomatosis,10%lung,and 42%multiple locations.Regarding the first line palliative chemotherapy treatments:50%received gemcitabine plus nab-paclitaxel;28%,modified fluorouracil,leucovorin,irinotecan and oxaliplatin,and 16%were administered gemcitabine.42%had a weight loss>5%in the three months(mo)preceding diagnosis.21 patients with a SIRI≥2.3×10^(3)/L exhibited a trend towards a lower median OS compared to those with a SIRI<2.3×10^(3)/L(4 vs 18 mo;P<0.000).Among 21 patients with>5%weight loss before diagnosis,the median OS was 6 mo,in contrast to 19 mo for those who did not experience such weight loss(P=0.003).Patients with a weight loss>5%showed higher SIRI levels.This difference was statistically significant(P<0.000).For patients with a SIRI<2.3×10^(3)/L,those who did not lose>5%of their weight had an OS of 20 mo,compared to 11 mo for those who did(P<0.001).No association was found between carbohydrate antigen 19-9 levels≥1000 U/mL and weight loss.CONCLUSION A higher SIRI was correlated with decreased survival rates in patients with metastatic pancreatic cancer and associated with weight loss.An elevated SIRI is suggested as a predictor of survival,emphasizing the need for prospective validation in the upcoming PANTHEIA-SEOM study. 展开更多
关键词 Pancreatic cancer NUTRITION Prognostic factor INFLAMMATION Advanced cancer Systemic inflammatory response index weight loss
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Postoperative body weight change and its influencing factors in patients with gastric cancer
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作者 Yan Li Li-Hua Huang +3 位作者 Hui-Di Zhu Ping He Bei-Bei Li Li-Jing Wen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2242-2254,共13页
BACKGROUND The high incidence and mortality of gastric cancer(GC)pose a significant threat to human life and health,and it has become an important public health challenge in China.Body weight loss is a common complica... BACKGROUND The high incidence and mortality of gastric cancer(GC)pose a significant threat to human life and health,and it has become an important public health challenge in China.Body weight loss is a common complication after surgical treatment in patients with GC and is associated with poor prognosis and GC recurrence.However,current attention to postoperative weight change in GC patients remains insufficient,and the descriptions of postoperative weight change and its influencing factors are also different.AIM To investigate body weight changes in patients with GC within 6 mo after gastrectomy and identify factors that influence dynamic body weight changes.METHODS We conducted a prospective longitudinal study of 121 patients with GC and collected data before(T0)and 1(T1),3(T2),and 6(T3)mo after gastrectomy using a general data questionnaire,psychological distress thermometer,and body weight measurements.The general estimation equation(GEE)was used to analyze the dynamic trends of body weight changes and factors that influence body weight changes in patients with GC within 6 mo of gastrectomy.RESULTS The median weight loss at T1,T2,and T3 was 7.29%(2.84%,9.40%),11.11%(7.64%,14.91%),and 14.75%(8.80%,19.84%),respectively.The GEE results showed that preoperative body mass index(BMI),significant psychological distress,religious beliefs,and sex were risk factors for weight loss in patients with GC within 6 mo after gastrectomy(P<0.05).Compared with preoperative low-weight patients,preoperative obese patients were more likely to have weight loss(β=14.685,P<0.001).Furthermore,patients with significant psychological distress were more likely to lose weight than those without(β=2.490,P<0.001),and religious patients were less likely to lose weight 6 mo after gastrectomy than those without religious beliefs(β=-6.844,P=0.001).Compared to female patients,male patients were more likely to experience weight loss 6 mo after gastrectomy(β=4.262,P=0.038).CONCLUSION Male patients with GC with high preoperative BMI,significant psychological distress,and no religious beliefs are more likely to lose weight after gastrectomy. 展开更多
关键词 Gastric cancer GASTRECTOMY weight loss Influencing factors Body mass index
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Improved theory of generalized meteo-ballistic weighting factor functions and their use 被引量:1
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作者 Vladimir CECH Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期242-254,共13页
It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire ... It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget model.Trajectories calculated under non-standard conditions are considered to be perturbed.The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity functions.WFFs are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as well.We have found that the existing theory of WFF calculation has several significant shortcomings.The aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies found.Using this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms. 展开更多
关键词 EXTERIOR BALLISTIC Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity FUNCTION (Generalized) weighting (factor) function(curve) (Generalized) EFFECT FUNCTION Norm EFFECT
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Time Domain Full Waveform Inversion Based on Gradient Preconditioning with an Angle-Dependent Weighting Factor 被引量:1
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作者 XIA Dongming SONG Peng +6 位作者 LI Xishuang TAN Jun XIE Chuang WANG Shaowen LIU Kai ZHAO Bo MAO Shibo 《Journal of Ocean University of China》 SCIE CAS CSCD 2022年第6期1479-1486,共8页
There are lots of low wavenumber noises in the gradients of time domain full waveform inversion(FWI),which can seriously reduce the accuracy and convergence speed of FWI.Thus,we introduce an angle-dependent weighting ... There are lots of low wavenumber noises in the gradients of time domain full waveform inversion(FWI),which can seriously reduce the accuracy and convergence speed of FWI.Thus,we introduce an angle-dependent weighting factor to precondition the gradients so as to suppress the low wavenumber noises when the multi-scale FWI is implemented in the high frequency.Model experiments show that the FWI based on the gradient preconditioning with an angle-dependent weighting factor has faster convergence speed and higher inversion accuracy than the conventional FWI.The tests on real marine seismic data show that this method can adapt to the FWI of field data,and provide high-precision velocity models for the actual data processing. 展开更多
关键词 full waveform inversion low wavenumber noise angle-dependent weighting factor
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Minimum variance adaptive beamforming combined with coherence factor weighting applied to ultrafast active cavitation imaging 被引量:1
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作者 DING Ting HU Hong +1 位作者 YANG Lu GUI Zhi-guo 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第1期68-77,共10页
The ultrafast active cavitation imaging(UACI)based on plane wave transmission and delay-and-sum(DAS)beamforming has been developed to monitor cavitation events with a high frame rate.However,DAS beamforming leads to i... The ultrafast active cavitation imaging(UACI)based on plane wave transmission and delay-and-sum(DAS)beamforming has been developed to monitor cavitation events with a high frame rate.However,DAS beamforming leads to images with limited resolution and contrast.In this paper,minimum variance(M V)adaptive beamforming and coherence factor(CF)weighting are combined to achieve an MVCF-based UACI,which can improve the cavitation imaging quality.The detailed algorithm evaluation has been investigated from both simulation and experimental data The simulation data include10point targets and a cyst,while the experimental data are obtained by detecting the dissipation of cavitation bubbles in water excited by a single element transducer with frequency of1.2MHz.The advantages of the proposed methodology as well as the comparison with conventional B-mode,DAS?M V,DAS-CF and MV on the basis of compressive sensing(CS)(called MVCS)beamformers are discussed.The results show that MVCF beamformer has a significant improvement in terms of both resolutions and signal-to-noise ratio(SN R).The MVCF-based UACI has a SNR at21.82dB higher,lateral and axial resolution at2.69times and1.93times?respectively,which were compared with those of B-mode active cavitation mapping.The MVCF-based UACI can be used to image the residual cavitation bubbles with a higher SNR and better spatial resolution 展开更多
关键词 ultrafast active cavitation imaging (UACI) cavitation event adaptive beamforming coherence factor weighting
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Model Predictive Yaw Control Using Fuzzy-Deduced Weighting Factor for Large-Scale Wind Turbines
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作者 Shuowang Zhang Lingxiang Huang +3 位作者 Dongran Song Ke Xu Xuebing Yang Xiaoping Song 《Energy Engineering》 EI 2021年第2期237-250,共14页
Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy.To track the stochastic and fast-changing wind direction,the nacelle is rotated by the yaw control sys... Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy.To track the stochastic and fast-changing wind direction,the nacelle is rotated by the yaw control system.Therein,a difficulty consists in the variation speed of the wind direction much faster than the rotation speed of the nacelle.To deal with this difficulty,model predictive control has been recently proposed in the literature,in which the previewed wind direction is employed into the predictive model,and the estimated captured energy and yaw actuator usage are two contradictive objectives.Since the performance of the model predictive control strat-egy relies largely on the weighting factor that is designed to balance the two objectives,the weighting factor should be carefully selected.In this study,a fuzzy-deduced scheme is proposed to derive the weighting factor of the mod-el predictive yaw control.For the proposed fuzzy-deduced strategy,the variation degree and the increment of the wind direction during the predictive horizon are used as the inputs,and the weighting factor is the output,which is dynamically adjusted.The proposed model predictive yaw control is demonstrated by some simulations using real wind data and its performance is compared with the conventional model predictive control with thefixed weighting factor.Comparison results confirm the outweighing performance of the proposed control strategy over the conventional one. 展开更多
关键词 Wind turbine yaw control weighting factor fuzzy logic control
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Problem of the reference height of the projectile trajectory as a reduced meteo-ballistic weighting factor 被引量:1
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作者 Vladimir CECH Ludek JEDLICKA Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第2期131-140,共10页
This paper deals with the issue of preparation of the aiming angles with the use of tabular firing tables and needed determination of the ballistic elements μ_B(ballistic wind w_B,w_(xB),w_(ZB),ballistic(virtual) tem... This paper deals with the issue of preparation of the aiming angles with the use of tabular firing tables and needed determination of the ballistic elements μ_B(ballistic wind w_B,w_(xB),w_(ZB),ballistic(virtual) temperature τ_B.ballistic density p_B) from the standardized met messages.The weighting factors are used for the calculation of ballistic elements μ_B that are incorporated into the trajectory calculations characteristics of weapon and ammunition.Two different methodologies practically used in the praxis are analysed and compared.For the comparison of the two methodologies the reference height of trajectory determined from the weighting factor functions is employed.On the basis of the analyses conducted,the potential for further increase in accuracy of these aiming angles preparation methods is pointed out. 展开更多
关键词 加权因子 弹道风 基准 气象 弹丸 制备方法 瞄准角 道密度
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Mining Weights of Land Evaluation Factors Based on Cloud Model and Correlation Analysis 被引量:17
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作者 HU Shiyuan LI Deren +1 位作者 LIU Yaolin LI Deyi 《Geo-Spatial Information Science》 2007年第3期218-222,共5页
The veracity of land evaluation is tightly related to the reasonable weights of land evaluation fac- tors. By mapping qualitative linguistic words into a fine-changeable cloud drops and translating the uncertain facto... The veracity of land evaluation is tightly related to the reasonable weights of land evaluation fac- tors. By mapping qualitative linguistic words into a fine-changeable cloud drops and translating the uncertain factor conditions into quantitative values with the uncertain illation based on cloud model, and then, inte- grating correlation analysis, a new way of figuring out the weight of land evaluation factors is proposed. It may solve the limitations of the conventional ways. 展开更多
关键词 cloud models correlation analysis land evaluation factor weight data mining
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Maternal risk factors for low birth weight for term births in a developed region in China:a hospital-based study of 55,633 pregnancies 被引量:6
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作者 Yihua Bian Zhan Zhang +2 位作者 Qiao Liu Di Wu Shoulin Wang 《The Journal of Biomedical Research》 CAS 2013年第1期14-22,共9页
Low birth weight (LBW) is an important risk factor for neonatal and infant mortality and morbidity in adults.. How- ever, no large scale study on the prevalence of LBW and related maternal risk factors in China has ... Low birth weight (LBW) is an important risk factor for neonatal and infant mortality and morbidity in adults.. How- ever, no large scale study on the prevalence of LBW and related maternal risk factors in China has been published. To explore the effects of maternal factors on LBW for term birth in China, we conducted a hospital-based retrospective study of 55, 633 Chinese pregnancy cases between 2001 and 2008. Maternal sociodemographic data, history of infer- tility and contraceptive use were obtained. Their medical status and diseases during pre-pregnancy were examined by physical examination at the first antenatal care visit. Maternal medical status before childbirth and pregnancy outcomes, including body weight, infant gender, multiple pregnancy and congenital anomalies, were recorded. Univariate and multivariate logistic regression, and linear regression were used to investigate the relationship be- tween maternal factors and term LBW. The general incidence of term LBW was 1.70% in the developed area of China. After preliminary analysis using the univariate model, low primary education, anemia, hypertensive disor- ders, placental previa, oligohydramnios and premature rupture of membrane were predicted as independent factors of term LBW in the multivariate model. Furthermore, the decrease in annual frquencies of these risk factors were major causes of gradual decline in the incidence of LBW (from 2.43% in 2001 to 1.21% in 2008). The study dem- onstrated that among maternal factors, primary education, anemia and hypertensive disorders could contribute to LBW for term birth even in the most developed area of China. 展开更多
关键词 maternal factors low birth weight (LBW) hypertensive disorders multivariate regression analysis
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Water-conserving mining influencing factors identification and weight determination in northwest China 被引量:11
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作者 Limin Fan Liqiang Ma +2 位作者 Yihe Yu Shuokang Wang Yujun Xu 《International Journal of Coal Science & Technology》 EI 2019年第1期95-101,共7页
Water-conserving mining is an effective way to alleviate the contradiction between fragile ecological environment and high-intensity coal mining in the arid and semi-arid region of northwest China. It needs to conside... Water-conserving mining is an effective way to alleviate the contradiction between fragile ecological environment and high-intensity coal mining in the arid and semi-arid region of northwest China. It needs to consider the engineering and geological conditions, hydrogeological conditions and mining methods of coal seams. From the three aspects, this paper systematically analyzes the influencing factors and establishes an identification model with multi-level structures. The model includes three primary factors (including the engineering and geological conditions, hydrogeological conditions and mining methods), nine secondary factors (including overlying strata thickness, aquiclude, mining parameters and etc.), sixteen third-tier factors (including the faults, aquiclude thickness and effective mining height and etc.) and twelve fourth-tier factors (including the fault throw exp on ent, aquiclude permeability and coal pillar sizes and etc.). On the basis, the analytic hierarchy process is used to build the judgment matrix and obtain the weight of each influencing factor. The results indicate that the overlying strata thickness, aquiclude and effective mining height are the most import a nt factors among the primary factors of engineering and geological conditions, hydrogeological conditions and mining methods, respectively. The research results could provide theoretical references for the water-conserving mining of coal resources in northwest China. 展开更多
关键词 Water-conserving MINING In FLUE ncing factors Analytic hierarchy process JUDGMENT matrix weight
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Weight Determining of Factors Influencing Grain Output Based on Entropy Weight Method 被引量:3
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作者 LI Jun Department of Management,Xijing University,Xi’an 710123,China 《Asian Agricultural Research》 2012年第3期7-9,共3页
This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in ... This article selects 8 main factors(the number of rural employees,total power of agricultural machinery,effective irrigation area of crops,growing area of grain crops,fertilizer consumption,electricity consumption in rural areas,area affected and area covered) as the factors influencing grain output,and offers the method of determining weight of factors influencing grain output using entropy weight method.According to the relevant data in the period 1985-2005,we analyze the weight of factors influencing grain output in China by example.The results show that the electricity consumption in rural areas has the greatest impact on grain output,followed by total power of agricultural machinery,fertilizer consumption and area covered.To increase grain output,we must enhance the degree of mechanization,free people from the former process of direct cultivation,strengthen water conservancy construction,and do a good job in disaster prevention and mitigation. 展开更多
关键词 GRAIN OUTPUT ENTROPY weight method factors weight
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Radar emitter signal recognition based on multi-scale wavelet entropy and feature weighting 被引量:16
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作者 李一兵 葛娟 +1 位作者 林云 叶方 《Journal of Central South University》 SCIE EI CAS 2014年第11期4254-4260,共7页
In modern electromagnetic environment, radar emitter signal recognition is an important research topic. On the basis of multi-resolution wavelet analysis, an adaptive radar emitter signal recognition method based on m... In modern electromagnetic environment, radar emitter signal recognition is an important research topic. On the basis of multi-resolution wavelet analysis, an adaptive radar emitter signal recognition method based on multi-scale wavelet entropy feature extraction and feature weighting was proposed. With the only priori knowledge of signal to noise ratio(SNR), the method of extracting multi-scale wavelet entropy features of wavelet coefficients from different received signals were combined with calculating uneven weight factor and stability weight factor of the extracted multi-dimensional characteristics. Radar emitter signals of different modulation types and different parameters modulated were recognized through feature weighting and feature fusion. Theoretical analysis and simulation results show that the presented algorithm has a high recognition rate. Additionally, when the SNR is greater than-4 d B, the correct recognition rate is higher than 93%. Hence, the proposed algorithm has great application value. 展开更多
关键词 emitter recognition multi-scale wavelet entropy feature weighting uneven weight factor stability weight factor
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Benefit allocation model of distributed photovoltaic power generation vehicle shed and energy storage charging pile based on integrated weighting-Shapley method 被引量:8
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作者 Qingkun Tan Peng Wu +3 位作者 Wei Tang Chang Cao Chengjie Wang Yu Zhang 《Global Energy Interconnection》 2020年第4期375-384,共10页
In this study,to develop a benefit-allocation model,in-depth analysis of a distributed photovoltaic-powergeneration carport and energy-storage charging-pile project was performed;the model was developed using Shapley ... In this study,to develop a benefit-allocation model,in-depth analysis of a distributed photovoltaic-powergeneration carport and energy-storage charging-pile project was performed;the model was developed using Shapley integrated-empowerment benefit-distribution method.First,through literature survey and expert interview to identify the risk factors at various stages of the project,a dynamic risk-factor indicator system is developed.Second,to obtain a more meaningful risk-calculation result,the subjective and objective weights are combined,the weights of the risk factors at each stage are determined by the expert scoring method and entropy weight method,and the interest distribution model based on multi-dimensional risk factors is established.Finally,an example is used to verify the rationality of the method for the benefit distribution of the charging-pile project.The results of the example indicate that the limitations of the Shapley method can be reasonably avoided,and the applicability of the model for the benefit distribution of the charging-pile project is verified. 展开更多
关键词 Charging pile Benefit distribution Risk factor Integrated weighting method Shapley model
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Risk Factors for Low Birth Weight and Preterm Birth:A Population-based Case-control Study in Wuhan,China 被引量:3
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作者 汪静 曾云 +6 位作者 倪泽敏 王姽 刘淑运 李灿 余朝利 王齐 聂绍发 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第2期286-292,共7页
Low birth weight(LBW) and preterm birth(PB) are associated with newborn mortality and diseases in adulthood.We explored factors related to LBW and PB by conducting a population-based case-control study from Januar... Low birth weight(LBW) and preterm birth(PB) are associated with newborn mortality and diseases in adulthood.We explored factors related to LBW and PB by conducting a population-based case-control study from January 2011 to December 2013 in Wuhan,China.A total of 337 LBW newborn babies,472 PB babies,and 708 babies with normal birth weights and born from term pregnancies were included in this study.Information of newborns and their parents was collected by trained investigators using questionnaires and referring to medical records.Univariate and logistic regression analyses with the stepwise selection method were used to determine the associations of related factors with LBW and PB.Results showed that maternal hypertension(OR=6.78,95% CI:2.27–20.29,P=0.001),maternal high-risk pregnancy(OR=1.53,95% CI:1.06–2.21,P=0.022),and maternal fruit intake ≥300 g per day during the first trimester(OR=1.70,95% CI:1.17–2.45,P=0.005) were associated with LBW.BMI ≥24 kg/m^2 of mother prior to delivery(OR=0.48,95% CI:0.32–0.74,P=0.001) and gestation ≥37 weeks(OR=0.01,95% CI:0.00–0.02,P〈0.034) were protective factors for LBW.Maternal hypertension(OR=3.36,95% CI:1.26–8.98,P=0.016),maternal high-risk pregnancy(OR=4.38,95% CI:3.26–5.88,P〈0.001),maternal meal intake of only twice per day(OR=1.88,95% CI:1.10–3.20,P=0.021),and mother liking food with lots of aginomoto and salt(OR=1.60,95% CI:1.02–2.51,P=0.040) were risk factors for PB.BMI ≥24 kg/m^2 of mother prior to delivery(OR=0.66,95% CI:0.47–0.93,P=0.018),distance of house from road ≥36 meters(OR=0.72,95% CI:0.53– 0.97,P=0.028),and living in rural area(OR= 0.60,95% CI:0.37–0.99,P=0.047) were protective factors for PB.Our study demonstrated some risk factors and protective factors for LBW and PB,and provided valuable information for the prevention of the conditions among newborns. 展开更多
关键词 case-control low birth weight newborn preterm birth risk factors
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