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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:12
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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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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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Evaluation of Impacts of Sea Level Rise on the Coast of Mohammedia(Morocco):Land at Risk of Flooding and Socioeconomic Impacts
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作者 Khouakhi Abdou Maria Snoussi +1 位作者 Otmae Raji Saida Niazi 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期43-43,共1页
One of the significant consequences of the climate change predicted for the next decades is the sea and ocean level rise.The coastal zone of Mohammedia (Morocco),a site of significant socio-economic activeties largely... One of the significant consequences of the climate change predicted for the next decades is the sea and ocean level rise.The coastal zone of Mohammedia (Morocco),a site of significant socio-economic activeties largely open to the Atlantic Ocean,is thus confronted with hydrodynamic agents and a possible sea level rise,whose impacts will result in an immersion of the low topography areas。 展开更多
关键词 climate change sea level RISE Mohammedia COAST INUNDATION risk SOCIOECONOMIC IMPACTS adaptation
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基于层次分析-熵权法和莫兰指数的畜禽产品风险分析
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作者 王欣 朱晶滢 +3 位作者 邱景璇 范飞 吴立颖 葛宇 《农业机械学报》 北大核心 2026年第3期387-399,共13页
在对2016—2023年的全国畜禽产品抽检数据风险描述的基础上,采用层次分析-熵权法进行了风险分级;并基于全局和局部莫兰指数进行了风险空间分布特征的分析。研究表明,其主要风险来源于兽药和非法添加物,禽类和猪肉类产品的整体风险较高,... 在对2016—2023年的全国畜禽产品抽检数据风险描述的基础上,采用层次分析-熵权法进行了风险分级;并基于全局和局部莫兰指数进行了风险空间分布特征的分析。研究表明,其主要风险来源于兽药和非法添加物,禽类和猪肉类产品的整体风险较高,山东、河南、重庆等地的兽药残留较为突出,河南、湖南、重庆和贵州等地的非法添加物问题更为明显。恩诺沙星、氟苯尼考和氧氟沙星在全国范围内的综合风险最高;华东区域的兽药残留高风险污染物最为集中,山东出现的非法添加污染物种类最多;恩诺沙星、氯丙嗪、尼卡巴嗪及4种非法添加物的风险呈显著的空间聚集,恩诺沙星、多西环素等兽药残留及克伦特罗在特定地区呈“高-高”值聚集,应重点加强相关区域的风险防控。该研究结果可为我国畜禽产品的风险防控提供有益参考。 展开更多
关键词 畜禽肉及其副产品 层次分析法 熵权法 莫兰指数 风险等级 空间分布
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基于模糊隶属度函数的船舶驾驶智能避碰决策方法
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作者 李志特 孙继祥 《舰船科学技术》 北大核心 2026年第4期190-195,共6页
船舶驾驶智能决策需处理环境中的不确定性信息,并满足规则与经济性的多重约束。模糊隶属度函数可量化这种不确定性并识别碰撞风险,结合PSO-GA算法可在规则约束下高效寻得安全与经济的最优避碰决策平衡解。故本研究基于模糊隶属度函数的... 船舶驾驶智能决策需处理环境中的不确定性信息,并满足规则与经济性的多重约束。模糊隶属度函数可量化这种不确定性并识别碰撞风险,结合PSO-GA算法可在规则约束下高效寻得安全与经济的最优避碰决策平衡解。故本研究基于模糊隶属度函数的船舶驾驶智能避碰决策方法。首先,通过分析船舶会遇态势,明确船舶避让责任;然后,构建融合舷角、船速比、DCPA与TCPA的模糊隶属度函数,以精准评估碰撞危险度(CRI)。当CRI超出阈值时,启动PSO-GA混合优化算法,以转向幅度与航行时间为决策变量,以安全性与经济性目标为适应度函数,搜索避让船舶的最优避碰航线,实现智能避碰决策。实验结果表明:应用该方法得到的避碰决策(右转30.5°,航行0.16 h)可将船舶的CRI降至0.03,平均最优适应度值可低至0.2458,且仅需10代即可收敛,所生成的决策安全、经济且符合规则,为船舶驾驶中智能避碰提供了有效解决方案。 展开更多
关键词 模糊隶属度函数 船舶驾驶 智能避碰决策 碰撞危险度 PSO-GA算法
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企业数字化转型、动态能力与风险承担水平
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作者 陈烜 赵阳 《辽宁工程技术大学学报(社会科学版)》 2026年第1期34-42,共9页
针对企业数字化转型、动态能力与风险承担水平之间的关系问题,以2013—2024年中国A股制造业企业为研究样本,采用实证研究的方法,分析了企业数字化转型对风险承担水平的影响,并检验了动态能力的中介效应。研究发现:数字化转型能够提高企... 针对企业数字化转型、动态能力与风险承担水平之间的关系问题,以2013—2024年中国A股制造业企业为研究样本,采用实证研究的方法,分析了企业数字化转型对风险承担水平的影响,并检验了动态能力的中介效应。研究发现:数字化转型能够提高企业的风险承担水平,动态能力在数字化转型与企业风险承担水平之间发挥中介作用。研究结论为制造业企业提升风险承担水平提供参考。 展开更多
关键词 数字化转型 风险承担水平 吸收能力 适应能力 创新能力
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人工智能应用对商业银行竞争的影响研究
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作者 肖锋 徐高洁 《当代金融研究》 2026年第1期49-62,共14页
人工智能作为驱动银行业变革的核心技术,正深刻影响商业银行竞争格局。为探究其具体作用路径与效应,以2010-2024年105家商业银行为样本,综合运用面板固定效应模型与分位数回归展开实证分析。研究发现:人工智能应用显著加剧商业银行竞争... 人工智能作为驱动银行业变革的核心技术,正深刻影响商业银行竞争格局。为探究其具体作用路径与效应,以2010-2024年105家商业银行为样本,综合运用面板固定效应模型与分位数回归展开实证分析。研究发现:人工智能应用显著加剧商业银行竞争,且分位数回归揭示其对处于75%分位的中上游银行竞争效应最强,呈现“中间高、两端低”的非对称特征。机制分析表明,该效应通过提升经营效率、风险承担水平和收入多元化三条渠道实现;异质性分析显示,农商行、城商行与经济发达地区银行的竞争促进效应更为显著。在数字经济浪潮下,银行应加大AI技术投入,监管部门应实施差异化监管,推动银行业公平竞争与高质量发展。 展开更多
关键词 人工智能应用 商业银行竞争 经营效率 风险承担水平 收入多元化
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一种基于HAZOP-LOPA的碱回收燃烧工段安全仪表系统设计方法
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作者 汤伟 郑晓虎 +1 位作者 王孟效 王其林 《中国造纸》 北大核心 2026年第1期149-156,共8页
针对当前造纸工业安全仪表系统(SIS)设计方法存在的风险分析碎片化、定量评估不足等问题,本研究以碱回收燃烧工段汽包控制部分SIS设计为例,提出一种基于危险与可操作性分析-保护层分析(HAZOP-LOPA)的SIS定级及设计方法。首先对碱回收燃... 针对当前造纸工业安全仪表系统(SIS)设计方法存在的风险分析碎片化、定量评估不足等问题,本研究以碱回收燃烧工段汽包控制部分SIS设计为例,提出一种基于危险与可操作性分析-保护层分析(HAZOP-LOPA)的SIS定级及设计方法。首先对碱回收燃烧工段进行工艺流程节点划分,并设计对应的风险概率-后果二维风险矩阵,通过HAZOP方法系统识别该工段的潜在偏差与风险场景,结合LOPA分析构建独立保护层量化模型;然后基于风险传导特性建立保护层分析-安全完整性等级(LOPA-SIL)动态映射关系,对SIS等级进行合理定级,最后根据定级结果进行SIS的设计,并通过系统失效概率、剩余风险值等指标验证系统的有效性。结果表明,该方法可成功识别2项高风险场景并判定需增设SIL2级SIS,改进后将风险概率成功降至企业可接受水平(<1.0×10-6/年)。 展开更多
关键词 碱回收燃烧工段 HAZOP-LOPA 安全完整性等级 安全仪表系统 风险量化
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分红动因正当性水平、投资者异质信念与公司股票特质风险
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作者 姜涛 霍雨佳 《财经问题研究》 北大核心 2026年第1期101-114,共14页
深入探究公司股票特质风险的影响因素,对于优化公司治理、提高市场效率、保障投资者权益具有重要意义。本文运用双向固定效应模型实证检验了分红动因正当性水平对公司股票特质风险的影响及其作用机制。研究结果表明,分红动因正当性水平... 深入探究公司股票特质风险的影响因素,对于优化公司治理、提高市场效率、保障投资者权益具有重要意义。本文运用双向固定效应模型实证检验了分红动因正当性水平对公司股票特质风险的影响及其作用机制。研究结果表明,分红动因正当性水平对公司股票特质风险具有负向影响,投资者异质信念在分红动因正当性水平与公司股票特质风险的关系中发挥了中介效应,股利不平稳通过降低投资者异质信念程度负向调节了分红动因正当性水平与公司股票特质风险的关系。进一步分析发现:机构投资者能够更精准地甄别分红动因正当性水平,降低投资者异质信念程度,从而降低公司股票特质风险;区分市场态势发现,无论是在牛市还是在熊市,分红动因正当性水平对公司股票特质风险均具有显著的负向影响;以分红动因正当性水平较高的上市公司作为成份股构建的股票投资指数,收益表现更好。本文的研究结论为中国股票市场高质量发展提供了经验证据。 展开更多
关键词 分红动因正当性水平 公司股票特质风险 投资者异质信念 股利平稳性
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A Fault Risk Warning Method of Integrated Energy Systems Based on RelieF-Softmax Algorithm 被引量:3
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作者 Qidai Lin Ying Gong +2 位作者 Yizhi Shi Changsen Feng Youbing Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第9期929-944,共16页
The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multi... The integrated energy systems,usually including electric energy,natural gas and thermal energy,play a pivotal role in the energy Internet project,which could improve the accommodation of renewable energy through multienergy complementary ways.Focusing on the regional integrated energy system composed of electrical microgrid and natural gas network,a fault risk warning method based on the improved RelieF-softmax method is proposed in this paper.The raw data-set was first clustered by the K-maxmin method to improve the preference of the random sampling process in the RelieF algorithm,and thereby achieved a hierarchical and non-repeated sampling.Then,the improved RelieF algorithm is used to identify the feature vectors,calculate the feature weights,and select the preferred feature subset according to the initially set threshold.In addition,a correlation coefficient method is applied to reduce the feature subset,and further eliminate the redundant feature vectors to obtain the optimal feature subset.Finally,the softmax classifier is used to obtain the early warnings of the integrated energy system.Case studies are conducted on an integrated energy system in the south of China to demonstrate the accuracy of fault risk warning method proposed in this paper. 展开更多
关键词 Integrated energy system RelieF-softmax method fault characteristics fault risk level prediction
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重庆市建设用地土壤污染特征及时空变化分析
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作者 王健 王明星 +5 位作者 范例 张勇 龚先河 刘元元 袁胜 宾灯辉 《环境工程技术学报》 北大核心 2026年第1期331-342,共12页
重庆市作为长江经济带的核心城市之一,在推进长江流域生态保护文明建设方面具有重要作用。为了解重庆市优化产业布局、落实《中华人民共和国土壤污染防治法》等政策后,地块土壤污染特征及其变化情况,以重庆市建设用地为研究对象,基于201... 重庆市作为长江经济带的核心城市之一,在推进长江流域生态保护文明建设方面具有重要作用。为了解重庆市优化产业布局、落实《中华人民共和国土壤污染防治法》等政策后,地块土壤污染特征及其变化情况,以重庆市建设用地为研究对象,基于2019—2022年调查的138个污染地块从行业类型、土壤污染类型、污染程度及风险水平等方面进行分析。结果表明:1)与2019年以前相比,重庆市污染地块占比前3的行业有所变化,2019年以后依次为金属表面处理及热处理加工(18.12%)、基础化学原料制造(15.22%)、常用有色金属冶炼(13.04%),污染地块主要分布于中心城区,与我国珠三角、粤港澳大湾区、长三角等区域主要污染地块行业类型基本一致。2)与2019年以前相比,土壤污染类型不变,重点关注的污染物发生变化,2019年以后重金属-有机复合污染类型占污染地块的67.39%,多环芳烃(62.32%)、 As(52.9%)、总石油烃(51.45%)、 Cr(35.51%)、 Pb(32.61%)、Ni(31.16%)为主要污染物。3)采用《重庆市建设用地土壤污染程度分级评价技术指南(试行)》评价地块污染程度,主要为中度及轻度污染,占比约81%,其中炼焦、基础化学原料制造、农药制造、常用有色金属冶炼地块污染程度较高,污染范围较大,土壤污染风险水平较高。 展开更多
关键词 重庆市 行业类型 土壤污染特征 污染程度 土壤污染风险水平
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