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Alteration of Crime Risk Levels and Formal Aspect of Typical LowCost Housing Design Due to Site Conditions and Building Codes
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《Journal of Civil Engineering and Architecture》 2011年第11期967-978,共12页
As a component of the process of rationalization, lowcost housing Institution, as well as major investiment companies, commonly reuse a typical design as a standard. The goal of this procedure is to obtain cheaper cos... As a component of the process of rationalization, lowcost housing Institution, as well as major investiment companies, commonly reuse a typical design as a standard. The goal of this procedure is to obtain cheaper costs both in the construction and in the maintenance of an homogeneous lot of buildings. The paper shows that, nevertheless an identical design being proposed in different towns, the final results are buildings with a different aspect. This is mainly due to the influence of building codes of the urban plan of the specific town, and to the site conditions, such as street orientation, ground inclination and so on. As a result the paper offers the ability to evaluate the role of the external factors on a standard design (with the afore said scale vantages) under the criminological point of view as well. This may be considered a further vantage that aims to obtain a lower crime risk level in town design. 展开更多
关键词 Standardized housing design alterations crime risk levels.
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Artificial Neural Network Modeling of Healthy Risk Level Induced by Aircraft Pollutant Impacts around Soekarno Hatta International Airport 被引量:1
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作者 Salah Khardi Jermanto Setia Kurniawan +1 位作者 Irwan Katili Setyo Moersidik 《Journal of Environmental Protection》 2013年第8期28-39,共12页
Aircraft pollutant emissions are an important part of sources of pollution that directly or indirectly affect human health and ecosystems. This research suggests an Artificial Neural Network model to determine the hea... Aircraft pollutant emissions are an important part of sources of pollution that directly or indirectly affect human health and ecosystems. This research suggests an Artificial Neural Network model to determine the healthy risk level around Soekarno Hatta International Airport-Cengkareng Indonesia. This ANN modeling is a flexible method, which enables to recognize highly complex non-linear correlations. The network was trained with real measurement data and updated with new measurements, enhancing its quality and making it the ideal method for this research. Measurements of aircraft pollutant emissions are carried out with the aim to be used as input data and to validate the developed model. The obtained results concerned the improved ANN architecture model based on pollutant emissions as input variables. ANN model processes variables—hidden layers—and gives an output variable corresponding to a healthy risk level. This model is characterized by a 4-10-1 scheme. Based on ANN criteria, the best validation performance is achieved at epoch 28 from 34 epochs with the Mean Squared Error (MSE) of 9 × 10-3. The correlation between targets and outputs is confirmed. It validated a close relationship between targets and outputs. The network output errors value approaches zero. Further research is needed with the aim to enlarge the scheme of the ANN model by increasing its input variables. This is one of the major key defining environmental capacities of an airport that should be applied by Indonesian airport authorities. These would institute policies to manage or reduce pollutant emissions considering population and income growth to be socially positive. 展开更多
关键词 AIRCRAFT POLLUTANT Emissions Artificial Neural Network HEALTHY risk level
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Management of the Quality of Corrosion Protection of Structural Steel Based on Corrosion Risk Level
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作者 Volodymyr Korolov Yury Filatov +1 位作者 Natalya Magunova Petro Korolov 《材料科学与工程(中英文B版)》 2013年第11期740-747,共8页
关键词 防腐蚀保护 风险水平 质量管理 结构钢 基础 极限状态设计 防护涂料 管理技术
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RISK LEVEL ANALYSIS ON THE PREVENTIVE EROSION CAPACITY OF BRIDGES 被引量:1
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作者 Liang Zai-chao, Li Tai-lai (Collage of Water Resources and Hydraulic Engineering, Wuhan Unive rsity, Wuhan 430072, China) 《Journal of Hydrodynamics》 SCIE EI CSCD 2002年第1期117-121,共5页
Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge fai lures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The defi... Deficiency of the Preventive Erosion Capacity (PEC) of a bridge pier is the main factor leading to bridge fai lures. In this paper, the PEC of bridge piers was analyzed using the stochastic analysis method. The definitions of the reliability and risk level of a bridge p ier subjected to water erosion were proposed and a computational model for erosi on depth and risk level in was suggested. 展开更多
关键词 bridge erosion risk level reliabil ity stochastic variable
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Method for determining climatic design conditions based on the indoor thermal environment risk level 被引量:1
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作者 Xia Wu Zhe Tian +2 位作者 Yuanyuan Wang Jide Niu Chengzhi Tian 《Energy and Built Environment》 2021年第1期56-64,共9页
Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.I... Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.In this regard,the research proposes to construct the correlation between climatic design conditions and indoor thermal environment risk level,and explore the effect of uncertainty in building thermal performance on this correlation from the perspective of probability,thus realizing the process of selecting the climatic design conditions based on the requirement for indoor thermal environment risk level.Taking Guangzhou in China as an example,the new process of determining climatic design conditions is realized.On this basis,the difference between the traditional method and the present research method is compared.In the Chinese norm method,the indoor thermal environ-ment risk level of the building is between 0 and 0.03%when the climatic design conditions are selected with 0.57%cumulative frequency of occurrence;in the research method,the indoor thermal environment risk level of the building is between 0.2%and 0.6%when the climatic design conditions are selected with 0.57%indoor thermal environment risk level and 100%confidence level.The results indicate that the research method can meet the designer’s expectation for indoor thermal environment risk level in design more directly and accurately. 展开更多
关键词 Air-conditioning system design Climatic design conditions Indoor thermal environment risk level Building thermal performance
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Assessment of pollution levels and human health risk of heavy metals in dust deposited on Yerevan's tree leaves (Armenia) 被引量:11
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作者 N. Maghakyan G. Tepanosyan +2 位作者 O. Belyaeva L. Sahakyan A. Saghatelyan 《Acta Geochimica》 EI CAS CSCD 2017年第1期16-26,共11页
The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were eval... The total concentrations of Cd,As,Pb,Cr,Ni,Co,Zn,Cu,Ag,Hg,and Mo were determined in the atmospheric dust of the city of Yerevan by atomic absorption spectrometry(AAnalyst PE 800).Heavy metal pollution levels were evaluated by calculating geo-accumulation(I_(geo)) and summary pollution(Z_c) indices.Potential human health risk was assessed using the United States Environmental Protection agency's human health risk assessment model.The results show that mean contents of all elements tested except Ni and Cr were substantially higher than local geochemical background values.According to the I_(geo),Yerevan territory is strongly-to-extremely polluted by As,Ag,Hg,Mo,and Cd.The Z_c assessment indicated that very high pollution was detected in 36%of samples,high in 32%,average in 12%,and low in 20%.The health risk assessment revealed a noncarcinogenic risk(HI >1) for children at 13 samplings sites and for adults at one sampling site.For children the risk was due to elevated levels of Mo,Cd,Co,and As,while for adults,only Mo.Carcinogenic risk(>1:1,000,000) of As and Cr via ingestion pathway was observed in 25 and 14 samples,respectively.This study,therefore,is the base for further detailed investigations to organize problematic site remediation and risk reduction measures. 展开更多
关键词 Urban dust Heavy metals Pollution levels Health risk assessment
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A Systematic Assessment of Blood Lead Level in Children and Associated Risk Factors in China 被引量:7
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作者 WANG Lu LI Zhen +6 位作者 HUANG Shao Xin DU Chuang WANG Hong HE Li Ping BI Yong Yi SHI Yong WANG Chun Hong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第8期616-619,共4页
In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 a... In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 μg/L, and the prevalence of elevated BLL (EBLL, defined as BLL &ge;100 μg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China. 展开更多
关键词 BLL A Systematic Assessment of Blood Lead level in Children and Associated risk Factors in China
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Risk assessment and zoning of sea level rise in Shandong Province 被引量:1
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作者 LIU Qingrong LI Jian +5 位作者 RUAN Chengqing YIN Zhonghui JIAO Yan SUN Qing LIAN Xihu ZHONG Shan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第6期2014-2024,共11页
Sea level rise is a slow-onset disaster.We collected information about the natural and ecological environments,tides and sea levels,and socio-economic aspects to investigate the distribution and zoning of the risks fr... Sea level rise is a slow-onset disaster.We collected information about the natural and ecological environments,tides and sea levels,and socio-economic aspects to investigate the distribution and zoning of the risks from sea level rise across Shandong Province.The trends in sea level in different counties of Shandong Province were predicted using moving averages and a random dynamic analysis forecasting model,and the model outputs and socio-economic indicators were combined to assess the risks.The results show that the risks of sea level rise along the western coast of Bohai Bay and Laizhou Bay in Shandong Province were sufficiently large to warrant attention. 展开更多
关键词 SEA level RISE risk assessment risk ZONING
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A predictive score for retinopathy of prematurity by using clinical risk factors and serum insulin-like growth factor-1 levels 被引量:4
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作者 Yesim Coskun Ceyhun Dalkan +7 位作者 Ozge Yabas Ozlem Onay Demirel Elif Samiye Bayar Sibel Sakarya Tuba Muftuoglu Dilaver Ersanli Nerin Bahceciler ipek Akman 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第11期1722-1727,共6页
AIM:To detect the impact of insulin-like growth factor-1(IGF-1)and other risk factors for the early prediction of retinopathy of prematurity(ROP)and to establish a scoring system for ROP prediction by using clini... AIM:To detect the impact of insulin-like growth factor-1(IGF-1)and other risk factors for the early prediction of retinopathy of prematurity(ROP)and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS:The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS:Birth weights(BW),gestational weeks(GW)and the prevalence of breast milk consumption were lower,respiratory distress syndrome(RDS),bronchopulmonarydysplasia(BPD)and necrotizing enterocolitis(NEC)were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP(P〈0.05).Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW(〈1250 g),presence of intraventricular hemorrhage(IVH)and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION:In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants. 展开更多
关键词 ROP A predictive score for retinopathy of prematurity by using clinical risk factors and serum insulin-like growth factor-1 levels IVH IGF
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基于LDSCR-at-Risk的PPP项目可融资性评价
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作者 叶苏东 《北京交通大学学报(社会科学版)》 CSSCI 北大核心 2024年第3期141-148,共8页
通过分析传统的偿债备付率适用性及政府和社会资本合作(PPP)项目的特点,认为传统的偿债备付率不适合于PPP项目可融资性评价。因此,为了评价中长期债务的可融资性,提出了“平准化偿债备付率”(LDSCR),即在借款偿还期内,各年可用于还本付... 通过分析传统的偿债备付率适用性及政府和社会资本合作(PPP)项目的特点,认为传统的偿债备付率不适合于PPP项目可融资性评价。因此,为了评价中长期债务的可融资性,提出了“平准化偿债备付率”(LDSCR),即在借款偿还期内,各年可用于还本付息的资金折现到起始点的现值与贷款金额的比值;进一步提出“风险下的平准化偿债备付率”(LDSCR-at-Risk),即在给定的置信度下的平准化偿债备付率。运用蒙特卡洛仿真进行验证,结果表明:LDSCR-at-Risk可用于PPP项目的可融资性评价,且在可以评价具有风险的PPP项目可融资性的同时,还避免了如何确定项目的最低偿债备付率的问题,从而促进PPP项目融资的发展。 展开更多
关键词 PPP 可融资性 平准化偿债备付率 LDSCR-at-risk
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Is low postoperative cholesterol level really an independent risk factor of adverse outcomes after living donor liver transplantation?
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作者 Qing Liu Fu-Shan Xue +1 位作者 Gui-Zhen Yang Ya-Yang Liu 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第4期378-379,共2页
To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(s TC)changes on early allograft dysfunction and survival after living donor liver ... To the Editor:We read with great interest the article by Yang et al.[1]evaluating the effects of postoperative serum total cholesterol(s TC)changes on early allograft dysfunction and survival after living donor liver transplantation(LDLT).By the multivariate regression analysis,they showed that patients with s TC<1.42 mmol/L on postoperative day 3 had 4.08-fold and 2.72-fold greater risks of 展开更多
关键词 Is low postoperative cholesterol level really an independent risk factor of adverse outcomes after living donor liver transplantation TC AUC
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Inventory Model with Supply Disruption Risk and Service Level Constraint
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作者 WANG Quan-qing LI Zhen-guo LI Xiao-shen 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第3期412-418,共7页
We develop a newsvender model with service level constraint for oneproduct and multi-supplier system, where the supplies are susceptible to disruption risks. We prove the convexity of the programming problem,and provi... We develop a newsvender model with service level constraint for oneproduct and multi-supplier system, where the supplies are susceptible to disruption risks. We prove the convexity of the programming problem,and provide the necessary and sufficient conditions for the optimal order quantities. Through analysis or numerical experiments we observe the effects of the disrupt risk and the service level constraint on the optimal policy. We propose some managerial insights in managing the multi-source supply chain with disruption risks. 展开更多
关键词 inventory model disruption risk optimal policy service level
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改进K-SMOTE随机森林算法在地震信息发布安全风险评估中的应用研究 被引量:1
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作者 李亚龙 何琳 +2 位作者 万杰 潘丹 孙静 《地震工程学报》 北大核心 2025年第1期168-177,共10页
为有效地提高地震监测、预警、灾情评估等信息发布的安全性提出一种改进型K-SMOTE随机森林(RF)方法构建地震信息安全风险评估模型。该模型通过改进K-SMOTE算法中运用混合采样获得均衡度高的样本集,然后使用随机K折交叉验证方法进行样本... 为有效地提高地震监测、预警、灾情评估等信息发布的安全性提出一种改进型K-SMOTE随机森林(RF)方法构建地震信息安全风险评估模型。该模型通过改进K-SMOTE算法中运用混合采样获得均衡度高的样本集,然后使用随机K折交叉验证方法进行样本划分与模型优化,最终实现目标安全风险等级评估。对实际地震信息发布案例进行评测,文章所提方法构建模型评估准确率为92%,模型精确率和查全率分别为0.81和0.92,模型泛化能力强,能有效用于地震信息发布安全风险评估。本研究为完善地震信息发布安全评估体系、改进地震信息发布环境、降低安全风险提供了参考。 展开更多
关键词 地震信息发布 风险等级评估 改进K-SMOTE 随机森林 随机K折交叉验证
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Serum lipid levels and their risk factors in theGuangxi Mu Lao Zu population
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作者 LI Ke-la,YIN Rui-xing,LONG Xing-jiang,ZHANG Lin,LIU Wan-ying,HU Xi-jiang,CAO Xiao-li,MIAO Lin,WU Dong-feng, ZENG Huan-yu (Department of Cardiology,Institute of Cardiovascular Diseases, the First Affiliated Hospital,Guangxi Medical University, Nanning 530021,China) 《岭南心血管病杂志》 2011年第S1期155-156,共2页
Objectives Mu Lao Zu population.Methods A total of 1055 subjects of Mu Lao Zu were studied by a stratified randomized cluster sampling.Blood pressure,body height, body weight,waist circumference and serum lipid and ap... Objectives Mu Lao Zu population.Methods A total of 1055 subjects of Mu Lao Zu were studied by a stratified randomized cluster sampling.Blood pressure,body height, body weight,waist circumference and serum lipid and apolipoprotein(Apo) levels were measured.The data were compared with those in 969 subjects of Han Chinese from the same region.In order to evaluate the association of hyperlipidemia with nine possible riks factors,multivariate logistic regression analysis was also performed in the combined population of Mu Lao Zu and Han,Mu Lao Zu,and Han;respectively. Results The levels of total cholesterol,triglyceride, low-density lipoprotein cholesterol and ApoB in Mu Lao Zu were significantly higher than those in Han(P【0.05-0.001); but the levels of high-density lipoprotein cholesterol,ApoA1 and ApoA1/Apo were significantly lower than those in Han (P【0.001 ).The prevalence of hyperlipidemia and Hypercholesterolemia was also significantly higher in Mu Lao Zu than in Han(53.0%vs.46.1%,P【0.001) and(44.5%vs. 37.5%,P【0.001).There was no difference in the prevalence of hypertriglyceridemia between the both ethnic groups (22.8%vs.19.4%,P】0.05).Hyperlipidemia was positively correlated with age,BMI,and systolic blood pressureMu Lao Zu(P【0.05),whereas it was positively correlated with BMI and hypertension in Han(P【0.05 for each).Conclusions The serum lipid profiles,the prevalence of hyperlipidemia and the risk factors are different between the Mu Lao Zu and Han populations.The differences in serum lipid profiles between the two ethnic groups might result from different dietary habit,life style,as well as genetic factors,in ? To determine the serum lipid levels and their risk factors in the Guangxi. 展开更多
关键词 Serum lipid levels and their risk factors in theGuangxi Mu Lao Zu population
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安阳市内黄县外来入侵植物的调查研究 被引量:3
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作者 朱秀红 周琳坡 +4 位作者 刘宇凡 张龙冲 孙合祥 孙翱杰 茹广欣 《河南农业大学学报》 北大核心 2025年第1期68-78,共11页
【目的】明确安阳市内黄县外来植物的入侵现状,以期为外来植物入侵防控、生物多样性保护与生态安全管理提供依据。【方法】通过对内黄县17个乡镇168个位点开展实地调查,获取该地区外来入侵植物本底,并分析各入侵植物的生长状况;筛选出... 【目的】明确安阳市内黄县外来植物的入侵现状,以期为外来植物入侵防控、生物多样性保护与生态安全管理提供依据。【方法】通过对内黄县17个乡镇168个位点开展实地调查,获取该地区外来入侵植物本底,并分析各入侵植物的生长状况;筛选出外来入侵植物风险评估指标,形成风险评估体系,并对所有指标进行赋值,评估每一种外来植物的入侵风险。【结果】共计发现外来入侵植物44种,隶属于16科,菊科有15个物种,所占比例为34%;从地理起源上分,有5种类型,其中来自美洲的最多,有30种,所占比例为66.7%;生活型一共有7种,1 a生草本物种最多,为32种,所占比例为71.1%;Ⅰ级危害等级的外来入侵植物有3种,分别为小蓬草(小白酒草)(Erigeron canadensis L.)、牵牛(Ipomoea nil(L.)Roth)和黑麦草(Lolium perenne L.);Ⅱ级危害等级有6种,Ⅲ级危害有9种;Ⅳ级危害有8种;Ⅴ级危害有18种。【结论】须加强对外来入侵植物的管控。内黄县的外来植物侵害情况研究报告和入侵危害评价数据,对于当地以及其他地区制定管理策略、有效控制外来植物入侵具有一定借鉴价值。 展开更多
关键词 外来入侵植物 风险评估 危害等级 内黄县
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“专精特新”企业培育能否缓解企业创新“低端锁定”困境 被引量:7
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作者 湛泳 马从文 《科技进步与对策》 北大核心 2025年第3期130-140,共11页
中共二十大报告指出要完善科技创新体系,支持“专精特新”企业发展,解决关键技术领域“卡脖子”问题。运用双重差分模型检验“专精特新”企业培育对企业高端创新的作用机制及异质性特征。研究发现:①“专精特新”企业培育能助力企业高... 中共二十大报告指出要完善科技创新体系,支持“专精特新”企业发展,解决关键技术领域“卡脖子”问题。运用双重差分模型检验“专精特新”企业培育对企业高端创新的作用机制及异质性特征。研究发现:①“专精特新”企业培育能助力企业高端创新,缓解企业创新“低端锁定”困境;②“专精特新”企业培育通过缓解企业融资约束、提高企业风险承担水平和增加分析师关注促进企业高端创新;③数字金融、数字化转型和高管海外背景能强化“专精特新”企业培育对企业高端创新的影响,而行业竞争则会削弱“专精特新”企业培育对企业高端创新的影响;④“专精特新”企业培育通过促进企业高端创新提高企业国际化深度。据此,提出完善“专精特新”企业培育政策和提高企业高端创新的相关建议。 展开更多
关键词 “专精特新”企业培育 企业高端创新 融资约束 企业风险承担水平 分析师关注
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大数据环境下政府审计防范系统性金融风险效果研究 被引量:2
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作者 喻采平 彭红霞 黄岩渠 《财经理论与实践》 北大核心 2025年第1期94-102,共9页
依据2008—2021年中国23个省份非平衡面板数据,考量大数据环境下政府审计防范系统性金融风险效果。结果显示:政府审计在大数据环境下仍能显著抑制系统性金融风险,金融系统的风险累积在此过程中发挥中介效应,大数据发展水平对政府审计防... 依据2008—2021年中国23个省份非平衡面板数据,考量大数据环境下政府审计防范系统性金融风险效果。结果显示:政府审计在大数据环境下仍能显著抑制系统性金融风险,金融系统的风险累积在此过程中发挥中介效应,大数据发展水平对政府审计防范系统性金融风险具有负向调节作用。异质性检验显示,政府审计对东部、西部地区以及低市场化水平地区系统性金融风险防范作用更显著。鉴于此,建议进一步推进政府审计数字化转型,完善政府审计对金融风险累积的抑制机制,因地制宜实施审计策略。 展开更多
关键词 政府审计 系统性金融风险 风险累积 大数据发展水平
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高速公路出口衔接城市路段交通风险时空动态识别研究 被引量:1
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作者 胡立伟 杨灿 +4 位作者 周泽禹 潘江雄 陈家乐 龚麒 马思月 《交通运输系统工程与信息》 北大核心 2025年第3期358-371,共14页
为更加准确地对高速公路出口衔接城市路段的交通风险进行识别和评估,本文提出一种综合考虑风险接近水平(RNL)和风险严重程度(RSL)的换道时空风险指数(TRCI)。首先利用轨迹数据分析路段换道车辆的轨迹特性、换道位置特性和换道影响因素,... 为更加准确地对高速公路出口衔接城市路段的交通风险进行识别和评估,本文提出一种综合考虑风险接近水平(RNL)和风险严重程度(RSL)的换道时空风险指数(TRCI)。首先利用轨迹数据分析路段换道车辆的轨迹特性、换道位置特性和换道影响因素,结果表明,车辆换道相对位置集中分布在0.1~0.2和0.4~0.6区间;然后提出换道碰撞时间(LCTTC),将LCTTC与碰撞余量(MTC)映射得到RNL和RSL以描述换道时空风险特性,利用邓氏灰色关联度方法进行权重分析得到换道时空风险指数TRCI,使用累计频率法确定严重、较严重、一般与轻微冲突的阈值分别为0.30、0.51、0.67,对比TRCI与碰撞时间(TTC)、跟车时距(GAP)对换道冲突风险的识别情况;最后将高速公路出口衔接城市路段划分为32个区段和128个区块,进行换道冲突分布特性分析及风险等级评定。结果表明,车辆换道时空风险指数TRCI的风险有效识别率平均较TTC提升85.10%,平均较GAP提升49.75%;基于XGBoost算法构建的高速公路出口衔接城市路段车辆换道冲突严重性预测模型的性能更优,F1分数较梯度提升决策树模型(GBDT)和随机森林模型(RF)分别提升了11.28%和1.40%。研究路段中区段3~区段5、区段14~区段18以及区段21~区段23的冲突点最密集,区段4、区段5、区段15~区段18处于高风险状态,说明出口匝道、导向车道和地面道路的合流点是换道冲突风险最高的区域。本文可为高速公路出口衔接城市路段的交通运行安全分析及管理提供理论支撑。 展开更多
关键词 交通工程 换道风险评估 换道时空风险指数 高速公路出口衔接城市路段 风险等级评定
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三门峡水库汛期分期汛限水位运用方案研究 被引量:2
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作者 娄书建 刘世帆 《泥沙研究》 北大核心 2025年第2期32-36,50,共6页
防洪安全与库区泥沙淤积一直是制约三门峡水库综合效益发挥的关键因子。进入21世纪,黄河来沙量的趋势性减少和黄河流域生态保护与高质量发展战略的实施,为三门峡水库运用方式调整创造了有利的内在条件和外部环境。基于水库历年运用实践... 防洪安全与库区泥沙淤积一直是制约三门峡水库综合效益发挥的关键因子。进入21世纪,黄河来沙量的趋势性减少和黄河流域生态保护与高质量发展战略的实施,为三门峡水库运用方式调整创造了有利的内在条件和外部环境。基于水库历年运用实践与体会,提出了三门峡水库后汛期抬高库水位至310/312 m的运用方案,分析了其防洪安全、库区淤积风险及综合效益,结果表明,三门峡水库后汛期抬高库水位至310/312 m运用较当前305 m运用,基本不会对水库防洪安全、库区多年冲淤平衡及潼关高程的稳定产生不利的附加影响,同时能够充分发挥三门峡水库水资源利用、水生态保护及水能发电等综合效益。 展开更多
关键词 三门峡水库 分期汛限水位 风险 效益
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急性应激对风险情境下道德决策的影响及其认知机制
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作者 占友龙 肖青茵 +1 位作者 黎志华 肖啸 《中国临床心理学杂志》 北大核心 2025年第5期920-931,1041,共13页
目的:考察急性应激对风险情境下大学生道德决策的影响及其认知机制。方法:实验1(n=52)和实验2(n=54)以男性大学生为被试,在通过特里尔社会应激测试诱发急性应激后,分别采用有风险的帮助和伤害困境任务对道德决策进行测量,并利用认知计... 目的:考察急性应激对风险情境下大学生道德决策的影响及其认知机制。方法:实验1(n=52)和实验2(n=54)以男性大学生为被试,在通过特里尔社会应激测试诱发急性应激后,分别采用有风险的帮助和伤害困境任务对道德决策进行测量,并利用认知计算建模技术进一步量化决策偏好。结果:两项实验均发现与控制组相比,应激组对风险助人选项的主观价值更高,表现出更低水平的损失厌恶参数和内疚厌恶参数,进而做出了更多的利他选择;然而,这种由急性应激引起的促进作用仅在50%~70%的风险水平下被显著观察到。结论:在风险情境下,大学生的道德决策符合“损失—内疚厌恶整合加工模型”,且急性应激促使他们冒险做出更多的利他决策,尤其是在中等偏高的风险水平下。 展开更多
关键词 急性应激 道德决策 风险水平 认知计算建模 认知机制
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