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Dynamic Forecasting of Traffic Event Duration in Istanbul:A Classification Approach with Real-Time Data Integration
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作者 Mesut Ulu Yusuf Sait Türkan +2 位作者 Kenan Menguc Ersin Namlı Tarık Kucukdeniz 《Computers, Materials & Continua》 SCIE EI 2024年第8期2259-2281,共23页
Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic incidents.These incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,re... Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic incidents.These incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,resulting in long waiting times,high carbon emissions,and other undesirable situations.It is vital to estimate incident response times quickly and accurately after traffic incidents occur for the success of incident-related planning and response activities.This study presents a model for forecasting the traffic incident duration of traffic events with high precision.The proposed model goes through a 4-stage process using various features to predict the duration of four different traffic events and presents a feature reduction approach to enable real-time data collection and prediction.In the first stage,the dataset consisting of 24,431 data points and 75 variables is prepared by data collection,merging,missing data processing and data cleaning.In the second stage,models such as Decision Trees(DT),K-Nearest Neighbour(KNN),Random Forest(RF)and Support Vector Machines(SVM)are used and hyperparameter optimisation is performed with GridSearchCV.In the third stage,feature selection and reduction are performed and real-time data are used.In the last stage,model performance with 14 variables is evaluated with metrics such as accuracy,precision,recall,F1-score,MCC,confusion matrix and SHAP.The RF model outperforms other models with an accuracy of 98.5%.The study’s prediction results demonstrate that the proposed dynamic prediction model can achieve a high level of success. 展开更多
关键词 Traffic event duration forecasting machine learning feature reduction shapley additive explanations(SHAP)
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Spectra of seismic force reduction factors of MDOF systems normalized by two characteristic periods 被引量:1
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作者 Li Xiao Tong Genshu Zhang Lei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期53-69,共17页
Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessd... Seismic force reduction factor(SFRF) spectra of shear-type multi-degree-of-freedom(MDOF) structures are investigated. The modified Clough model, capable of considering the strength-degradation/hardening and stiffnessdegradation, is adopted. The SFRF mean spectra using 102 earthquake records on a typical site soil type(type C) are constructed with the period abscissa being divided into three period ranges to maintain the peak features at the two sitespecific characteristic periods. Based on a large number of results, it is found that the peak value of SFRF spectra may also exist for MDOF, induced by large high-mode contributions to elastic base shear, besides the mentioned two peak values. The variations of the stiffness ratio λk and the strength ratio λF of the top to bottom story are both considered. It is found that the SFRFs for λF ≤λk are smaller than those for λF > λk. A SFRF modification factor for MDOF systems is proposed with respect to SDOF. It is found that this factor is significantly affected by the story number and ductility. With a specific λF(= λk0.75), SFRF mean spectra are constructed and simple solutions are presented for MDOF systems. For frames satisfying the strong column/weak beam requirement, an approximate treatment in the MDOF shear-beam model is to assign a post-limit stiffness 15%-35% of the initial stiffness to the hysteretic curve. SFRF spectra for MDOF systems with 0.2 and 0.3 times the post-limit stiffness are remarkably larger than those without post-limit stiffness. Thus, the findings that frames with beam hinges have smaller ductility demand are explained through the large post-limit stiffness. 展开更多
关键词 seismic force reduction factor multi-degree of freedom modifi ed Clough model characteristic period highmode eff ect post-limit stiff ness analysis
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EXISTENCE OF PERIODIC SOLUTIONS FOR A DIFFERENTIAL INCLUSION SYSTEMS INVOLVING THE p(t)-LAPLACIAN 被引量:4
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作者 葛斌 薛小平 周庆梅 《Acta Mathematica Scientia》 SCIE CSCD 2011年第5期1786-1802,共17页
We study a nonlinear periodic problem driven by the p(t)-Laplacian and having a nonsmooth potential (hemivariational inequalities). Using a variational method based on nonsmooth critical point theory for locally L... We study a nonlinear periodic problem driven by the p(t)-Laplacian and having a nonsmooth potential (hemivariational inequalities). Using a variational method based on nonsmooth critical point theory for locally Lipschitz functions, we first prove the existence of at least two nontrivial solutions under the generalized subquadratic and then establish the existence of at least one nontrivial solution under the generalized superquadratic. 展开更多
关键词 p(t)-Laplacian periodic solution variable exponent Sobolev space minimax principle generalized subdifferential local linking reduction method
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REDUCING PERIODIC NOISE USING SOFT MORPHOLOGY FILTER 被引量:2
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作者 JiZhen MingZhong +1 位作者 LiQi WuQinghua 《Journal of Electronics(China)》 2004年第2期159-162,共4页
A novel spatial domain method--soft morphology filter is presented for reducing the periodic noise in image processing. The simulation results are presented to demonstrate the effectiveness of the method in comparison... A novel spatial domain method--soft morphology filter is presented for reducing the periodic noise in image processing. The simulation results are presented to demonstrate the effectiveness of the method in comparison with a frequency domain method and other spatial domain filters. 展开更多
关键词 Soft morphology Noise reduction periodic noise
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Development of Rainfall Intensity Duration Frequency Curves for Mumbai City, India 被引量:1
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作者 P. E. Zope Eldho T. I. V. Jothiprakash 《Journal of Water Resource and Protection》 2016年第7期756-765,共11页
The change in rainfall pattern and intensity is becoming a great concern for hydrologic engineers and planners. Many parts of the world are experiencing extreme rainfall events such as experienced on 26<sup>th&l... The change in rainfall pattern and intensity is becoming a great concern for hydrologic engineers and planners. Many parts of the world are experiencing extreme rainfall events such as experienced on 26<sup>th</sup> July 2005 in Mumbai, India. For the appropriate design and planning of urban drainage system in an area, Intensity Duration Frequency (IDF) curves for given rainfall conditions are required. The aim of the present study is to derive the IDF curves for the rainfall in the Mumbai city, Maharashtra, India. Observed rainfall data from 1901 pertaining to Colaba and from 1951 of the Santacruz rain gauge stations in Mumbai are used in the present study to derive the IDF curves. Initially, the proposed IDF curves are derived using an empirical equation (Kothyari and Garde), by using probability distribution for annual maximum rainfall and then IDF curves are derived by modifying the equation. IDF curves developed by the modified equation gives good results in the changing hydrologic conditions and are compatible even with the extreme rainfall of 26<sup>th</sup> July 2005 in Mumbai. 展开更多
关键词 RAINFALL Intensity duration Return period FREQUENCY IDF Curves
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Impact of Educational Materials on the Duration of Exclusive Breastfeeding Assured by Women Who Delivered at the Souissi Maternity Hospital in Rabat
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作者 Amina Bennis Fatima Zahra Laamiri +4 位作者 Anas Ansari Chebguiti Hassan Aguenaou Mustapha Mrabet Aicha Kharbach Amina Barkat 《Open Journal of Obstetrics and Gynecology》 2017年第13期1300-1318,共19页
Background: The practice of exclusive breastfeeding (EB) in Morocco has witnessed a worrying decline in recent decades, contrary to the recommendations of the World Health Organization (WHO) which advocates it during ... Background: The practice of exclusive breastfeeding (EB) in Morocco has witnessed a worrying decline in recent decades, contrary to the recommendations of the World Health Organization (WHO) which advocates it during the first six months as a significant public health tool. The present study aims to assess the impact of educational materials on mothers’ behaviour with regard to keeping up EB as long as six months, at least. Methods: This is a cohort study with a prospective collection of data over a period of one year, through a questionnaire-based survey of 500 women who delivered at the Souissi Maternity Hospital in Rabat. The subjects were divided into an intervention group sensitized, during the medical visit, by means of information delivered orally about breastfeeding and a booklet containing instructions on breastfeeding management and the benefits of EB, especially when extended for the first six months;and a control group attending the same operation with no awareness-rising through educational materials. To assess EB rates, the subjects had been followed for six months through telephone. Results: 372 women who delivered were followed, 194 from the intervention group and 178 from the control group. The remaining 128 women not followed were lost sight of. A higher percentage of mothers in the intervention group exclusively breastfed their babies up to the age of six months compared to the control group, 55.2% against 38.8% (p = 0.002). The main reason produced by most mothers who ceased to exclusively breastfeed their babies is milk insufficiency. Conclusion: The postnatal nutritional education strategy based on the distribution of educational materials has considerably raised the number of women who exclusively breastfed their babies until the age of six months. 展开更多
关键词 EXCLUSIVE BREASTFEEDING EDUCATIONAL Material duration POSTNATAL period BREASTFEEDING PRACTICES
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COVID-19 patient with an incubation period of 27 d:A case report
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作者 Xue Du Yang Gao +8 位作者 Kai Kang Yang Chong Mei-Ling Zhang Wei Yang Chang-Song Wang Xiang-Lin Meng Dong-Sheng Fei Qing-Qing Dai Ming-Yan Zhao 《World Journal of Clinical Cases》 SCIE 2021年第21期5955-5962,共8页
BACKGROUND As a highly contagious disease,coronavirus disease 2019(COVID-19)is wreaking havoc around the world due to continuous spread among close contacts mainly via droplets,aerosols,contaminated hands or surfaces.... BACKGROUND As a highly contagious disease,coronavirus disease 2019(COVID-19)is wreaking havoc around the world due to continuous spread among close contacts mainly via droplets,aerosols,contaminated hands or surfaces.Therefore,centralized isolation of close contacts and suspected patients is an important measure to prevent the transmission of COVID-19.At present,the quarantine duration in most countries is 14 d due to the fact that the incubation period of severe acute respiratory syndrome coronavirus type 2(SARS-CoV-2)is usually identified as 1-14 d with median estimate of 4-7.5 d.Since COVID-19 patients in the incubation period are also contagious,cases with an incubation period of more than 14 d need to be evaluated.CASE SUMMARY A 70-year-old male patient was admitted to the Department of Respiratory Medicine of The First Affiliated Hospital of Harbin Medical University on April 5 due to a cough with sputum and shortness of breath.On April 10,the patient was transferred to the Fever Clinic for further treatment due to close contact to one confirmed COVID-19 patient in the same room.During the period from April 10 to May 6,nucleic acid and antibodies to SARS-CoV-2 were tested 7 and 4 times,respectively,all of which were negative.On May 7,the patient developed fever with a maximum temperature of 39℃,and his respiratory difficulties had deteriorated.The results of nucleic acid and antibody detection of SARS-CoV-2 were positive.On May 8,the nucleic acid and antibody detection of SARS-CoV-2 by Heilongjiang Provincial Center for Disease Control were also positive,and the patient was diagnosed with COVID-19 and reported to the Chinese Center for Disease Control and Prevention.CONCLUSION This case highlights the importance of the SARS-CoV-2 incubation period.Further epidemiological investigations and clinical observations are urgently needed to identify the optimal incubation period of SARS-CoV-2 and formulate rational and evidence-based quarantine policies for COVID-19 accordingly. 展开更多
关键词 COVID-19 Incubation period Quarantine duration SARS-CoV-2 Case report
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Multifactor dimensionality reduction analysis of syndrome characteristics of chronic persistent asthma
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作者 Yanyan Meng Aiping Chen +4 位作者 Qi Shi Yue Yan Chaolumen Han Huiyuan Sun Youlin Li 《Journal of Traditional Chinese Medical Sciences》 2015年第3期159-165,共7页
Objective:To analyze the syndrome characteristics in patients with chronic persistent asthma.Methods:365 patients(121 males,244 females,60.829.1 years old)with chronic persistent asthma were enrolled in this cross-sec... Objective:To analyze the syndrome characteristics in patients with chronic persistent asthma.Methods:365 patients(121 males,244 females,60.829.1 years old)with chronic persistent asthma were enrolled in this cross-sectional study.The information of syndrome,symptoms,signs,tongue coating and pulse were collected from all patients.The syndrome characteristics of chronic persistent asthma were examined through the multifactor dimensionality reduction(MDR)analysis and the results were verified by the Chi-square test.Results:The results of the MDR analysis and the Chi-square test showed the following positive correlation of the interaction among:the deficiency syndrome of the lung and spleen and deep pulse,disinclination to talk due to lack of qi,fatigue,lassitude and thick tongue coating;the deficiency syndrome of the lung and kidney and dizziness and disinclination to talk due to lack of qi,fatigue,lassitude and pallid complexion;the syndrome of phlegm-heat obstructing the lung and rapid pulse,abdominal distension,disinclination to talk due to lack of qi,frequent urination and lassitude;the syndrome of phlegm-dampness obstructing the lung and disinclination to talk due to lack of qi,greasy coating,fatigue and lassitude.(P<.05 for all).Conclusion:The syndrome of chronic persistent asthma is characterized by fatigue and lassitude due to dysfunction of the lung,spleen and kidney. 展开更多
关键词 Bronchial asthma Chronic persistent period Traditional Chinese medicine Syndrome characteristics Multifactor dimensionality reduction
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Study on Nursing Effects of Liposuction and Volume Reduction Surgery for Lymphedema Perioperative Nursing Care
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作者 Wei Zheng Fei Li 《Journal of Clinical and Nursing Research》 2022年第1期55-58,共4页
Objective:To study the nursing effect of liposuction and volume reduction in the treatment of lymphedema during the perioperative period.Method:A total of 68 patients treated with liposuction volume reduction surgery ... Objective:To study the nursing effect of liposuction and volume reduction in the treatment of lymphedema during the perioperative period.Method:A total of 68 patients treated with liposuction volume reduction surgery for pseudo-lymphedema of lower limbs admitted from May 2019 to May 2020 in a tertiary hospital in Xi’an,Shaanxi Province were selected,and they were divided into observation group and control group by random grouping method.There were 34 cases in each group.The control group took routine care during the perioperative period,while the observation group performed full care during the perioperative period.The complication rate and pain degree of the two groups were compared.Results:The complication rate of the study group was 5.88%,while that of the control group was 26.67%.Compared with the study group,the complication rate was significantly higher than that of the control group,and the gap was statistically significant(P>0.05).The pain scores of patients in the study group were significantly lower than those in the control group at 3 and 6 days after surgery,and the gap was statistically significant(P>0.05).Conclusion:Lymphedema should be taken care of during the perioperative period of liposuction and volume reduction,which can effectively reduce the occurrence of pain and complications.It is worthy of extensive clinical promotion. 展开更多
关键词 Liposuction volume reduction surgery LYMPHEDEMA Perioperative period COMPLICATIONS PAIN
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利用Periodic Fourier法研究橡胶混凝土隔振基础对轨道振动的影响 被引量:1
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作者 金浩 刘维宁 +1 位作者 周顺华 孙晓静 《噪声与振动控制》 CSCD 2015年第3期144-148,共5页
地下铁道轨道减振措施研究是一个受到持续关注的问题,本文创新性地引入橡胶混凝土隔振基础这一概念。并利用Peiodic-Fourier方法,探讨了橡胶混凝土隔振基础物理参数对钢轨振动位移的影响。研究结果表明:(1)高频激励荷载引起的钢轨位移... 地下铁道轨道减振措施研究是一个受到持续关注的问题,本文创新性地引入橡胶混凝土隔振基础这一概念。并利用Peiodic-Fourier方法,探讨了橡胶混凝土隔振基础物理参数对钢轨振动位移的影响。研究结果表明:(1)高频激励荷载引起的钢轨位移比低频激励荷载引起的钢轨位移小;(2)橡胶混凝土隔振基础刚度越大,相应的共振频率越大,但引起的钢轨振动位移越小;(3)橡胶混凝土隔振基础阻尼越大,相应的共振频率越小,且引起的钢轨振动位移也越小。 展开更多
关键词 振动与波 橡胶混凝土 地下铁道 减振 periodic-Fourier方法 钢轨位移
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Periodic Defect Boundary-Mediated Activity of Electrocatalytic Oxygen Reduction Reactions of Fe-N-C Catalysts 被引量:1
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作者 Ziwei Wang Huiting Niu +3 位作者 Tiantian Wu Shujiang Ding Bao Yu Xia Yaqiong Su 《Renewables》 2024年第3期213-221,共9页
The introduction of defects can adjust the activity of graphene-based single-atom catalysts for oxygen reduction reactions(ORR).Herein,we for the first time investigate the ORR catalytic activity of FeN_(4)sites embed... The introduction of defects can adjust the activity of graphene-based single-atom catalysts for oxygen reduction reactions(ORR).Herein,we for the first time investigate the ORR catalytic activity of FeN_(4)sites embedded on graphene with four types of line-defective boundary via density functional theory calculations.Our results show that periodic line defects consisting of pentagon-pentagon-octagon(C_(585))or quad-octagon chains(C_(484))can significantly enhance ORR activity,owing to the optimized electronic structures of FeN_(4)sites.The spin magnetic moment and the valence state of the Fe atom are both well correlated with the ORR overpotential.Experimental investigations further corroborate that FeN_(4)with a high degree of defects exhibits better ORR activity and stability compared to FeN_(4)sites of pristine graphene and commercial Pt/C.This work unravels the influence of the periodic defect boundary on the ORR performance of Fe-N-C catalysts and paves the way towards the rational design of highly effective single-atom electrocatalysts. 展开更多
关键词 density functional theory Fe-N-C catalysts oxygen reduction reaction periodic defect electrocatalyst
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Influences of different definitions of the winter NAO index on NAO action centers and its relationship with SST 被引量:1
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作者 JING Yujie LI Yangchun +1 位作者 XU Yongfu FAN Guangzhou 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期320-328,共9页
Winter North Atlantic Oscillation(NAO)indexes from observations based on various winter durations are compared.Results show that there are significant differences in the interannual and decadal variations of these NAO... Winter North Atlantic Oscillation(NAO)indexes from observations based on various winter durations are compared.Results show that there are significant differences in the interannual and decadal variations of these NAO indexes.For the same data source,a different definition of winter duration can lead to different signs of NAO index in some years,which mainly appear to be in the period of decadal phase transition.The different winter durations induce different cycles of the observation-based NAO.The longer the winter duration,the stronger the decadal variation.The NAO defined by different winter durations also can generate different descriptions of the NAO action centers,including the position and movement.The longer the winter duration,the more southerly action centers appear to be.The movement of the action centers affects not only site-based NAO indexes but also those defined by other methods,such as empirical orthogonal function(EOF)analysis.The length of time used in EOF analysis has a great influence on the spatial pattern of the NAO mode,which results in a considerable difference between the corresponding NAO indexes.Regardless of which NAO index is used,the NAO-related SST anomalies show the same tripole pattern.The longer the winter duration,the more significant the relationship between the NAO and SST affected by the timescale of sea-air interaction. 展开更多
关键词 NAO index winter duration period action centers sea surface temperature
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Availability-based maintenance optimization under unequal inspection period and imperfect repair 被引量:1
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作者 Liu Yang Su Chun 《Journal of Southeast University(English Edition)》 EI CAS 2018年第3期303-308,共6页
Taking the multi-component system as research object, a maintenance optimization model based on the unequal inspection period and imperfect repair is established by considering the requirement of expected availability... Taking the multi-component system as research object, a maintenance optimization model based on the unequal inspection period and imperfect repair is established by considering the requirement of expected availability for improving the system's availability. An age reduction factor is used to describe the effect of imperfect repair, and the modelling approach for the unequal inspection period is proposed. Unavailable situations are classified into three kinds of independent cases, and the availability is calculated accordingly. Based on the analysis of the relationship between the unavailable cases and the unequal inspection period, an optimization model under imperfect repair is established to optimize the system's expected availability. A case study of a wind turbine is provided, and three key components, i.e. gearbox, generator and spindle, are considered. The optimization results of the unequal inspection period model and the equal inspection period model are compared. The results show that the unequal inspection period model based on availability can update the maintenance plan so as to optimize maintenance activities and improve the system's availability. 展开更多
关键词 age reduction inspection period unequal periodmaintenance maintenance optimization AVAILABILITY
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Characterization and quantification of within-year variation of snow-cover elevation in mountainous regions, eastern Tibet
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作者 Jie Gao XuDong Fu +2 位作者 TongLiang Gong GuangQian Wang Hao Wang 《Research in Cold and Arid Regions》 2011年第5期400-407,共8页
Fluctuating snow-covered elevation (FSCE) was conceptualized and proposed to characterize within-year variation of the border between snow-covered and snow-free area in mountainous regions. Two parameters, namely me... Fluctuating snow-covered elevation (FSCE) was conceptualized and proposed to characterize within-year variation of the border between snow-covered and snow-free area in mountainous regions. Two parameters, namely median of snow flee period (Tm) and snow free duration (AT), were defined to quantify FSCE. A regression model of FSCE was developed for the Lhasa River Basin, Niyang River Basin, and Changdu region in eastern Tibet. Statistical analysis of the snow-products data with a spatial resolution of 25km×25km shows that: (1) Tm correlates weakly with geographical and topographic factors, having the yearly mean value of July 31; (2) △T correlates significantly with the average elevation of the snow-products cell, having the yearly mean value of nearly five months (i.e., 151 days); (3) the region begins snow disappearance in late April and finishes snow coverage in mid November, being snow-free from late June to mid September and snow-covered from December to March in the next year. In addi- tion, snow-products with higher spatial resolution will be helpful to characterize FSCE in smaller spatial scales. 展开更多
关键词 fluctuating snow-covered elevation (FSCE) eastem Tibet median of snow-flee period duration of snow-flee period
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The Analysis of Accelerograms for the Earthquake Resistant Design of Structures
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作者 Victor Corchete 《International Journal of Geosciences》 2010年第1期32-37,共6页
In this paper, the analysis of ground motions (displacements, velocities and accelerations) has been performed focused to the seismic design. The relationships between the peak ground acceleration (PGA), the peak grou... In this paper, the analysis of ground motions (displacements, velocities and accelerations) has been performed focused to the seismic design. The relationships between the peak ground acceleration (PGA), the peak ground velocity (PGV), the peak ground displacement (PGD) and the bracketed duration, with the earthquake magnitude, are presented and their validity and applicability for seismic design is discussed. Finally, the dominant periods of the ground motions (displacement, velocity and acceleration) are obtained from their Fourier Spectrum. Their validity and applicability for the seismic design is discussed also. The results presented in this paper show that the relationships that exist between the important parameters: PGA, PGV, PGD and duration;and the earthquake magnitude, allow the prediction of the values for these parameters, in terms of the magnitude for future strong motions. These predictions can be very useful for seismic design. Particularly, the prediction of the magnitude associated to the critical acceleration, because the earthquakes with magnitude greater than this critical magnitude can produce serious damages in a structure (even its collapsing). The application of the relationships obtained in this paper must be very careful, because these equations are dependent on the source area, location and type of structure. The dominant periods of the ground motions (displacement, velocity and acceleration) that are computed and presented in this paper, are also important parameters for the seismic design, because recent studies have shown that the earthquake shaking is more destructive on structures having a natural period around some of these dominant periods. These parameters must also be handled with caution, because they show dependence with the source area, location and type of structure. 展开更多
关键词 Seismic Design Bracketed duration PEAK GROUND Acceleration (PGA) PEAK GROUND Velocity (PGV) PEAK GROUND Displacement (PGD) Dominant periodS
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Evaluation of Energy-Efficiency Standards for Room Air Conditioners in the US
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作者 Alex Lekov Victor Franco Steve Meyers 《Open Journal of Energy Efficiency》 2012年第2期9-20,共12页
This article describes an analysis of the energy and economic impacts of possible energy efficiency standards for room air conditioners on both U.S. consumers and the nation as a whole. We used two metrics to determin... This article describes an analysis of the energy and economic impacts of possible energy efficiency standards for room air conditioners on both U.S. consumers and the nation as a whole. We used two metrics to determine the effect of standards on a representative sample of U.S. consumers: life-cycle cost change and payback period. For the national impact analysis, we evaluated national energy savings attributable to each potential standard, the monetary value of the energy savings to consumers of room air conditioners, the increased total installed costs because of standards, and the net present value of the difference between the value of energy savings and increased total installed costs. Our analysis indicates that standards for room air conditioners at efficiency level 3, which is 17% more efficient than today’s typical unit in the case of room air conditioners less than 6000 Btu/h with louvers and 12% more efficient in the case of room air conditioners 8000 - 13,999 Btu/h with louvers, would save close to one quad of energy over 30 years and have a net present value of consumer benefit of between ?$0.14 billion and $1.82 billion, depending on the discount rate. In addition, such standards would reduce carbon dioxide emissions and NOx emissions. 展开更多
关键词 ENERGY Efficiency STANDARDS Room Air Conditioners Consumer Benefit ENERGY SAVINGS LIFE-CYCLE Cost Payback period Emissions reductionS
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早期应用贝利尤单抗治疗系统性红斑狼疮患者的效果及对激素减量的影响分析
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作者 欧阳楚君 卢瑞荣 +3 位作者 韦锋 梁灼源 郭静静 冯明亮 《中国现代药物应用》 2024年第2期40-45,共6页
目的观察早期应用(诱导缓解期3个月内)贝利尤单抗治疗系统性红斑狼疮(SLE)的效果及对激素减量的影响。方法选取83例使用贝利尤单抗治疗的SLE患者,两组均使用甲泼尼龙及吗替麦考酚酯作为背景用药。根据患者诱导缓解期开始使用贝利尤单抗... 目的观察早期应用(诱导缓解期3个月内)贝利尤单抗治疗系统性红斑狼疮(SLE)的效果及对激素减量的影响。方法选取83例使用贝利尤单抗治疗的SLE患者,两组均使用甲泼尼龙及吗替麦考酚酯作为背景用药。根据患者诱导缓解期开始使用贝利尤单抗的时间分为早期组(35例)和对照组(48例)。早期组在诱导缓解期≤3个月时开始使用贝利尤单抗治疗,对照组在诱导缓解期>3个月时开始使用贝利尤单抗治疗。比较两组血常规指标[白细胞计数(WBC)、中性粒细胞计数(Neut)、淋巴细胞计数(Lym)、血小板计数(PLT)、血红蛋白(Hb)]、肝肾功能指标[白蛋白(ALB)、血肌酐(SCr)]和血沉(ESR)水平、免疫功能指标[免疫球蛋白G(IgG)、免疫球蛋白A(IgA)、免疫球蛋白M(IgM)、球蛋白、补体C3、补体C4]、激素减量值和系统性红斑狼疮疾病活动指数(SLEDAI-2000评分)及主要器官损害情况。结果早期组治疗24周时的Neut水平(4.39±1.59)×10^(9)/L明显低于对照组的(6.56±3.09)×10^(9)/L,治疗12周时的Lym水平(1.73±0.49)×10^(9)/L、Hb水平(122.85±15.38)g/L和治疗24周时的Lym水平(1.59±0.49)×10^(9)/L、Hb水平(123.20±16.70)g/L明显高于对照组的(1.48±0.42)×10^(9)/L、(105.89±16.91)g/L和(1.38±0.34)×10^(9)/L、(103.42±25.63)g/L,有统计学差异(P<0.05)。早期组治疗24周时的ALB水平(41.20±3.07)g/L明显高于对照组的(38.50±6.06)g/L,治疗12周时的SCr水平(55.46±16.40)μmol/L和治疗24周时的SCr水平(54.79±16.15)μmol/L明显低于对照组的(74.46±24.21)、(69.34±20.95)μmol/L,治疗12周时的ESR水平(24.44±10.63)mm/h明显低于对照组的(32.37±11.21)mm/h,有统计学差异(P<0.05)。早期组治疗12和24周时的IgG和IgA水平明显低于对照组,治疗12周时的球蛋白水平明显低于对照组,治疗12和24周时的C3水平明显高于对照组,有统计学差异(P<0.05)。治疗12和24周时,早期组的激素减量值(60.49±27.42)、(68.23±22.12)mg明显高于对照组的(21.00±6.96)、(28.37±7.60)mg,SLEDAI-2000评分(3.77±1.06)、(2.74±0.44)分明显低于对照组的(4.79±1.46)、(2.96±0.40)分,有统计学差异(P<0.05)。两组各种主要器官损害发生率对比,无统计学差异(P>0.05)。结论早期应用贝利尤单抗治疗SLE患者可改善贫血情况、肝肾功能、ESR水平及免疫功能,有利于更快降低激素用量,且不会增加主要器官损害发生风险。 展开更多
关键词 贝利尤单抗 系统性红斑狼疮 诱导缓解期 激素减量
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不同药剂对柞园栎凹翅萤叶甲防效初试
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作者 赵世文 赵鸿宇 +3 位作者 崔国杰 韩冰 穆秀奇 李喜升 《园艺与种苗》 CAS 2024年第8期81-82,86,共3页
[目的]有效降低栎凹翅萤叶甲危害,保证健康有序的柞蚕生产。[方法]采用试虫小区套袋药剂试验法,依据常规使用浓度,设置乐果50 mL、敌敌畏15 mL、敌克+敌克1号组合20 mL、蚕敌一扫光20 mL,各药剂兑水15 L配置成相应药剂溶液,以清水为对照... [目的]有效降低栎凹翅萤叶甲危害,保证健康有序的柞蚕生产。[方法]采用试虫小区套袋药剂试验法,依据常规使用浓度,设置乐果50 mL、敌敌畏15 mL、敌克+敌克1号组合20 mL、蚕敌一扫光20 mL,各药剂兑水15 L配置成相应药剂溶液,以清水为对照,进行药剂防效试验及持效期试验,24 h后调查试虫情况。[结果]蚕敌一扫光、敌敌畏、敌克+敌克1号对试虫防效较好,均可达85%以上,其中敌克+敌克1号防效达95%;持效期试验,敌克+敌克1号持效期3~5 d,其他药剂药后3 d防效均明显降低。[结论]敌克+敌克1号、蚕敌一扫光、敌敌畏对栎凹翅萤叶甲均有较好的防效,推荐有蚕柞园选用敌克+敌克1号,无蚕柞园选用蚕敌一扫光。 展开更多
关键词 药剂 栎凹翅萤叶甲 防效 持效期
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轴向流作用下均布非线性弹簧支承二维壁板的复杂响应
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作者 董宇 郑辉 杨翊仁 《计算力学学报》 CAS CSCD 北大核心 2024年第3期506-512,共7页
考虑刚性导流段和尾流段对流场的影响,建立轴向流作用下二维板的非线性流固耦合运动控制方程,用有限差分法对控制方程进行离散。为了克服差分网格较多时带来的计算规模较大的问题,对控制方程用主模态缩减法缩减自由度,然后对离散方程进... 考虑刚性导流段和尾流段对流场的影响,建立轴向流作用下二维板的非线性流固耦合运动控制方程,用有限差分法对控制方程进行离散。为了克服差分网格较多时带来的计算规模较大的问题,对控制方程用主模态缩减法缩减自由度,然后对离散方程进行数值积分,得到系统的复杂响应,分析其分岔和混沌特性。计算结果表明,以来流流速幅值和阻尼参数为可变参数时,系统具有极其复杂的动态响应,通过分岔图、相图和庞加莱截面图等方法判断了系统多种形式的周期、拟周期和混沌运动,在以来流流速幅值为可变参数时,系统一开始经由周期倍化分岔的方式进入混沌;在以阻尼系数为可变参数时,经由倒周期倍化分岔的方式从混沌运动退回到周期振动。 展开更多
关键词 二维壁板 周期倍化分岔 模态缩减
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创新驱动政策是否促进城市减污降碳协同增效?——来自国家创新型城市试点政策的经验证据 被引量:1
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作者 杨晓军 薛洪畅 《产业经济研究》 CSSCI 北大核心 2024年第3期1-14,共14页
在当前“双碳”目标和美丽中国建设背景下,以创新驱动政策为引领促进城市减污降碳协同增效,对于推动形成人与自然和谐发展现代化建设新格局具有重要意义。基于2004—2020年中国284个地级及以上城市数据,以国家创新型城市试点政策为准自... 在当前“双碳”目标和美丽中国建设背景下,以创新驱动政策为引领促进城市减污降碳协同增效,对于推动形成人与自然和谐发展现代化建设新格局具有重要意义。基于2004—2020年中国284个地级及以上城市数据,以国家创新型城市试点政策为准自然实验,构建多期双重差分模型实证检验该试点政策对减污降碳协同增效的影响及作用机制。研究结果表明,以国家创新型城市试点政策为代表的创新驱动政策能够显著促进城市减污降碳协同增效,该结论在经过平行趋势检验、安慰剂检验、PSM-DID等一系列稳健性检验后仍然成立。进一步的影响机制分析发现,创新驱动政策能够通过技术效应、结构效应和产业集聚效应促进城市减污降碳协同增效。此外,创新驱动政策在环境关注度高、环保目标约束强和资源配置效率高的城市中对减污降碳协同增效的促进效果更为明显。研究结论为充分利用创新驱动政策促进城市减污降碳协同增效,进而实现经济社会绿色转型提供了政策启示。 展开更多
关键词 创新驱动政策 减污降碳协同增效 国家创新型城市 技术效应 结构效应 产业集聚效应 多期双重差分模型
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