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数据故事化解释中分类型预测结果的反转点识别方法研究——基于LIME算法 被引量:2
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作者 靳庆文 朝乐门 张晨 《情报理论与实践》 北大核心 2024年第2期170-177,共8页
[目的/意义]实现数据故事化中的反转点识别,有助于非专业人士理解分类型预测结果的产生原因,同时对于推动故事情节发展并使其快速到达故事高潮点具有促进作用。[方法/过程]提出故事点与反转点概念,基于LIME解释技术和反转点识别过程,设... [目的/意义]实现数据故事化中的反转点识别,有助于非专业人士理解分类型预测结果的产生原因,同时对于推动故事情节发展并使其快速到达故事高潮点具有促进作用。[方法/过程]提出故事点与反转点概念,基于LIME解释技术和反转点识别过程,设计了用于数据故事化中反转点识别的算法方案,并提出了面向分类模型的反转点识别流程。[结果/结论]将反转点识别算法应用到贷款数据集,证明此算法在数据故事化过程中寻找反转点的有效性,在获得用户期望的预测结果和快速识别反转点方面具有应用价值。 展开更多
关键词 数据故事化 分类模型 反转点 lime算法
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Multi-scale analysis of carbon mineralization in lime-treated soils considering soil mineralogy 被引量:1
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作者 Dhanalakshmi Padmaraj Chinchu Cherian Dali Naidu Arnepalli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2296-2309,共14页
Mineral carbonation is emerging as a reliable CO_(2) capture technology that can mitigate climate change.In lime-treated clayey soils,mineral carbonation occurs through the carbonation of free lime and cementitious pr... Mineral carbonation is emerging as a reliable CO_(2) capture technology that can mitigate climate change.In lime-treated clayey soils,mineral carbonation occurs through the carbonation of free lime and cementitious products derived from pozzolanic reactions.The kinetics of the reactions in lime-treated clayey soils are variable and depend primarily on soil mineralogy.The present study demonstrates the role of soil mineralogy in CO_(2) capture and the subsequent changes caused by carbon mineralization in terms of the unconfined compressive strength(UCS)of lime-treated soils during their service life.Three clayey soils(kaolin,bentonite,and silty clay)with different mineralogical characteristics were treated with 4%lime content,and the samples were cured in a controlled environment for 7 d,90 d,180 d,and 365 d.After the specified curing periods,the samples were exposed to CO_(2) in a carbonation cell for 7 d.The non-carbonated samples purged with N2 gas were used as a benchmark to compare the mechanical,chemical-mineralogical,and microstructure changes caused by carbonation reactions.Experimental investigations indicated that exposure to CO_(2) resulted in an average increase of 10%in the UCS of limetreated bentonite,whereas the strength of lime-treated kaolin and silty clay was reduced by an average of 35%.The chemical and microstructural analyses revealed that the precipitated carbonates effectively filled the macropores of the treated bentonite,compared to the inadequate cementation caused by pozzolanic reactions,resulting in strength enhancement.In contrast,strength loss in lime-treated kaolin and silty clay was attributed to the carbonation of cementitious phases and partly to the tensile stress induced by carbonate precipitation.In terms of carbon mineralization prospects,lime-treated kaolin exhibited maximum carbonation due to the higher availability of unreacted lime.The results suggest that,in addition to the increase in compressive strength,adequate calcium-bearing phases and macropores determine the efficiency of carbon mineralization in lime-treated clayey soils. 展开更多
关键词 Clays MINERALOGY Carbon capture lime STRENGTH Pore structure
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Performance evaluation of laterite soil embankment stabilized with bottom ash,coir fiber,and lime
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作者 Yunusa Hamdanu SANI Amin EISAZADEH 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2334-2351,共18页
In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.... In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.This study explored the potential application of coir fiber-reinforced laterite soil-bottom ash mixtures as embankment materials in the tropics.The objective is to enhance engineered embankment slopes'erosion resistance and stability while offering reuse options for industrial byproducts.This study examined various mix designs for unconfined compressive strength(UCS)and permeability,utilizing 30%bottom ash(BA)and 1%coir fiber(CF)with varying sizes ranging from 10 to 40 mm,6%lime,and laterite soil(LS),followed by microstructural analyses.The results demonstrate that the compressive strength increases as the CF length increases to 25 mm.In contrast,permeability increases continuously with increasing CF length.Lime-treated mixtures exhibit superior short-and long-term strength and reduce permeability owing to the formation of cementitious materials,as confirmed by microstructural analyses.A lab-scale slope box was constructed to evaluate the surface erosion of the stabilized laterite soil embankment.Based on the rainfall simulation results,the LS-BA-CF mixtures show better resistance to erosion and deformation compared to untreated LS,especially when lime is added to the top layer.This study provides insights into a sustainable and cost-effective approach for slope stabilization using BA and CF,offering a promising solution for tropical regions susceptible to surface erosion and landslides. 展开更多
关键词 Lateritic soil Bottom ash Coir fiber lime Unconfined compressive strength PERMEABILITY FESEM/EDS Rainfall simulation tests
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Prediction of lime utilization ratio of dephosphorization in BOF steelmaking based on online sequential extreme learning machine with forgetting mechanism
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作者 Runhao Zhang Jian Yang +1 位作者 Han Sun Wenkui Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期508-517,共10页
The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting me... The machine learning models of multiple linear regression(MLR),support vector regression(SVR),and extreme learning ma-chine(ELM)and the proposed ELM models of online sequential ELM(OS-ELM)and OS-ELM with forgetting mechanism(FOS-ELM)are applied in the prediction of the lime utilization ratio of dephosphorization in the basic oxygen furnace steelmaking process.The ELM model exhibites the best performance compared with the models of MLR and SVR.OS-ELM and FOS-ELM are applied for sequential learning and model updating.The optimal number of samples in validity term of the FOS-ELM model is determined to be 1500,with the smallest population mean absolute relative error(MARE)value of 0.058226 for the population.The variable importance analysis reveals lime weight,initial P content,and hot metal weight as the most important variables for the lime utilization ratio.The lime utilization ratio increases with the decrease in lime weight and the increases in the initial P content and hot metal weight.A prediction system based on FOS-ELM is applied in actual industrial production for one month.The hit ratios of the predicted lime utilization ratio in the error ranges of±1%,±3%,and±5%are 61.16%,90.63%,and 94.11%,respectively.The coefficient of determination,MARE,and root mean square error are 0.8670,0.06823,and 1.4265,respectively.The system exhibits desirable performance for applications in actual industrial pro-duction. 展开更多
关键词 basic oxygen furnace steelmaking machine learning lime utilization ratio DEPHOSPHORIZATION online sequential extreme learning machine forgetting mechanism
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Cement and Lime Stabilization Effect on the Evolutivity of an Expansive Overconsolidated Clay
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作者 Mohamed Khemissa 《Journal of Civil Engineering and Architecture》 2024年第3期134-140,共7页
This paper presents and analyzes the results of a series of compaction,fragmentability and damage tests performed on an expansive overconsolidated clay treated with cement and lime.This clay was obtained from the urba... This paper presents and analyzes the results of a series of compaction,fragmentability and damage tests performed on an expansive overconsolidated clay treated with cement and lime.This clay was obtained from the urban site of Sidi-Hadjrès city(wilaya of M'sila,Algeria),where significant damages frequently appears in the road infrastructures,roadway systems and light structures.Tests results obtained show that the geotechnical parameters values deduced from these tests are concordant and confirm the evolutivity of this natural clay treated with composed Portland cement or extinct lime and compacted under optimum Proctor conditions. 展开更多
关键词 Expansive clay evolutivity treatment CEMENT lime fragmentability coefficient damage coefficient
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Assessment of Cement-Lime as Stabilizer on Mud Bricks
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作者 Chrisdel Chancelice Ndjeumi Djonga Paul Nestor Djomou +2 位作者 George Elambo Nkeng Fatoumata Adda Souaibou Soulemane Anong 《Journal of Materials Science and Chemical Engineering》 2024年第7期1-13,共13页
The aim of this study was to evaluate the compressive strength of clay bricks and their stability to water absorption by inserting stabilizers such as lime and cement of 0%, 4%, 6%, 8%, 10%, 12% to 14%. Spectrometric ... The aim of this study was to evaluate the compressive strength of clay bricks and their stability to water absorption by inserting stabilizers such as lime and cement of 0%, 4%, 6%, 8%, 10%, 12% to 14%. Spectrometric analysis was used to characterize the various stabilizers and the clay used, and tests of resistance and water absorption were also carried out. The clay was found to be an aluminosilicate (15.55% to 17.17% Al2O3 and 42.12% to 44.15% SiO2). The lime contains 90.84% CaO and the cement has 17.80% SiO2, 3.46% Al2O3, 2.43% Fe2O3 and 58.47% CaO in the combined form of tricalcium silicate, dicalcium silicate, tricalcium aluminate and ferro-tetra calcium aluminate. The results showed that the insertion of locally available stabilizers (lime and cement) improved the strength of the material by almost 80% when the lime was increased from 0% to 14% for 14 days. For compressed cement, a 65% increase in strength was observed under the same conditions. Strength increases with drying time, with a 52% increase in strength at 28 days compared to 14 days. Furthermore, compressed cement bricks have a more compact structure, absorbing very little water (32%). In view of all these results, cement appears to be the best stabilizer, and compression improves compressive strength and reduces water absorption. 展开更多
关键词 Cement-Stabilized Earth lime-Stabilized Earth Compressed Earth Brick Compressive Strength Water Absorption Test
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Efficacy of Pelletized Lime versus Limestone Sand for Forest Regeneration Enhancement in Pennsylvania, USA
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作者 Nesha L. Mizel William E. Sharpe Bryan R. Swistock 《Open Journal of Forestry》 2015年第2期221-234,共14页
The efficacy of limestone sand and pelletized lime for remediation of soil acidity was compared in order to determine if limestone sand was a more cost-effective alternative to pelletized lime. Between fall of 2002 an... The efficacy of limestone sand and pelletized lime for remediation of soil acidity was compared in order to determine if limestone sand was a more cost-effective alternative to pelletized lime. Between fall of 2002 and spring 2003, two forested sites in Pennsylvania were clear cut and fenced. Pelletized lime and limestone sand were applied to separate 400-m2 plots within the sites at rates of 2170 kg·ha-1 and 4335 kg·ha-1, respectively. Two additional 400-m2 plots were used as controls. A paired before-after control-impact study design was used to assess changes in soil, soil solution, vegetation and biomass after lime application. Soil samples were collected from the Oi, Oe + Oa, and A horizons before and after lime application. Woody and herbaceous vegetation was harvested from 1-m2 sub-plots before and after liming and bi-weekly soil solution samples were collected for six months following lime application. Analysis of variance procedures were used to compare changes in the treatment plots over time. Changes in soil chemistry following lime application were comparable on the limestone sand and pelletized lime plots. There was a significant increase in exchangeable Mg and Mg saturation in the Oe + Oa horizon on all of the lime treatment plots relative to controls, but a greater percentage of applied Ca and Mg was exchangeable in the O-horizon in pelletized lime plots nine months after liming. Plant biomass did not increase on the lime treatment plots relative to the control one year post treatment. The majority of applied Ca and Mg from pelletized lime and limestone sand remained in the litter layer, with little movement into the A-horizon after one growing season. These results indicated that the application of limestone sand at two times the rate of pelletized lime produced comparable changes in soil and soil solution chemistry at a fraction of the cost. 展开更多
关键词 Forest REGENERATION Pelletized lime limesTONE SAND SOIL SOIL Water
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Geo-Grid Combined with Concrete and Limestone Columns to Reduce the Embankment Subsidence Located on Inclined Layers of Soft Soil
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作者 Arash Rostami Morteza Askari Ziarati +1 位作者 Nima Asghari Saman Jahani 《International Journal of Geosciences》 2016年第4期572-583,共12页
Soft soil has low shear strength and its density is high;construction of embankments on them would cause problems such as large and non-uniform subsidence. One way to avoid these subsidence is using of geo-grid combin... Soft soil has low shear strength and its density is high;construction of embankments on them would cause problems such as large and non-uniform subsidence. One way to avoid these subsidence is using of geo-grid combined with cement and lime columns. Geo-grids due to their tensile strength, and cement and lime columns due to their bearing capacity and their body friction, reduce embankment subsidence. Extensive researches have been done in order to reduce the subsidence of the embankments located on the roads, but few studies have being done about the inclined embankments on soft soil layers. In this paper, the road embankment has been located on inclined soft soil layers;the study will try to reduce embankment subsidence and uniform them using geo-grid combined with cement and lime column subsidence. The results show that the realization of this issue will cause subsidence reduction and uniformity in the embankment surface. 展开更多
关键词 Inclined Layering Integration of Subsidence Geo-Grid Cement and lime Columns Software Plexis
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Contribution of the Incorporation of Poultry Litter and Limestone for the Fertility of Sandy Soil in the Brazilian Amazon
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作者 Juliana Guimaraes Gerola Juan Ricardo Rocha +1 位作者 Stella Cristiani Goncalves Matoso Leandro Dias da Silva 《Natural Resources》 2014年第15期958-967,共10页
Sandy soils have limitations for growing plants. In general, they have low fertility, high toxic aluminum content and low organic matter. The organic matter is responsible for most of the cation exchange capacity of t... Sandy soils have limitations for growing plants. In general, they have low fertility, high toxic aluminum content and low organic matter. The organic matter is responsible for most of the cation exchange capacity of these soils. Added to this, the low clay content and the structure of these soils with large volumes of macropores, determine their low water retention. An alternative is the incorporation of organic waste combined with the practice of liming. Thus, the aim of this study was to evaluate the contribution of the incorporation of poultry litter and limestone in the fertility of sandy soils in the Brazilian Amazon. The experiment was conducted in Colorado do Oeste, RO, on a Quartzipsamment in a completely randomized block design in a 4 × 4 × 2 factorial scheme, corresponding to four doses of poultry litter (0, 5, 10 and 15 mg·ha-1), its incorporation for four times (0, 75, 110 and 145 days) in the presence and absence of 2 mg·ha-1 of limestone, with six replications. The incorporation of 15 mg·ha-1 of poultry litter combined with 2 mg·ha-1 of limestone for 75 days after the merger raises several components of Quartzipsamment fertility, mainly being the availability of phosphorus. 展开更多
关键词 Quartzipsamments Organic Waste LIMING
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Sustainability of lime stabilized road subgrade in mountainous regions of Türkiye
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作者 Yavuz ABUT İlknur BOZBEY Ece KURT BAL 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2436-2452,共17页
In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and ... In this paper the use of lime stabilized subgrade for low volume roads in two regions with high mountains and different frost penetration conditions in Türkiye was investigated in terms of design,performance,and cost.Pavements on unstabilized and stabilized subgrade were designed for two regions(Izmir and Van),covering all climate variations.The resilient modulus of the lime stabilized subgrade with different soil pulverization levels for non-freezing and freezing conditions were taken from a previous laboratory study.Frost effects were considered in pavement design using two different approaches,including limited subgrade frost penetration method and reduced subgrade strength method.Detailed application and evaluation were performed for all steps.Lime stabilized subgrades significantly reduced the thickness of base courses,and the benefit of lime stabilization was highly dependent on soil pulverization level.A detailed cost analysis on the unstabilized and stabilized cases found that the use of lime stabilization in the subgrade provided significant initial cost savings.Comparative analysis by using the AASHTO(1993)method and KENPAVE software,and quantity effect of soil pulverization level on the performance of low volume roads from a service life perspective,show that subgrade resilient modulus can be estimated.It is also possible to make correct performance estimation in the field.The results of the study show that lime stabilization is a good solution for low volume roads in the mountainous regions of Türkiye. 展开更多
关键词 Aggregate Surfaced Roads lime Stabilization Soil Pulverization Levels Road Design Service Life Cost analyses
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CI Acid Orange 52 Dye Removal Using Natural and Formulated Clay-Lime Materials: Isotherm, Kinetic and Thermodynamic Studies
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作者 Fumba Gaston Essomba Jean Serge +4 位作者 Ankoro Naphtali Odogu Kouotou Daouda Bélibi Bélibi Placide Désiré Ndi Julius Nsami Ketcha Mbadcam Joseph 《Journal of Materials Science and Chemical Engineering》 2023年第11期48-74,共27页
The main objective of the study is to improve the removal efficiency of Ourlago-kaolin (Kao), sodium montmorillonite (Na-MMT), and two formulated clay-lime (F13 and F23) towards CI Acid Orange 52 dye (AO52). F13 and F... The main objective of the study is to improve the removal efficiency of Ourlago-kaolin (Kao), sodium montmorillonite (Na-MMT), and two formulated clay-lime (F13 and F23) towards CI Acid Orange 52 dye (AO52). F13 and F23 were obtained by chemical stabilization through thermal treatment at 300°C. Fourier Transform Infrared spectra showed different surface functional groups on the clay materials, X-ray diffraction patterns revealed the raw materials contain many crystalline phases, scanning electron microscopy micrographs showed the variation of the layered structures of different clay materials, energy dispersive X-Ray analysis micrographs revealed compositional information and thermogravimetric-differential scanning calorimetry curves indicated the higher weight loss of 11.26% and 11.38% were observed for F13 and F23 respectively. BET surface area analyzed gave 133.0071 m<sup>2</sup>•g<sup>−1</sup> for F13 and 132.34803 m<sup>2</sup>•g<sup>−1</sup> for F23. The optimum pH value was 2.0 for Kao and Na-MMT. The adsorption experiments indicated that F13 and F23 have the maximum uptake abilities of 7.8740 and 3.1645 mg•g<sup>−1</sup>, respectively, compared to Kao (0.8761 mg•g<sup>−1</sup>) and Na-MMT (2.6178 mg•g<sup>−1</sup>). The pseudo-second-order model well described the adsorption kinetic model of AO52 dye onto the overall samples;Langmuir and Freundlich’s isotherms appropriately described the uptake mechanism. The positive values of ∆G° and negative value ∆H° indicated that the adsorption process was spontaneous and endothermic for Na-MMT, and non-spontaneous and exothermic for Kao, F13, and F23 because of their positive values of ∆G° and negative value of ∆H°. The modified clays have higher adsorption capacities and better life cycles compared hence opening new avenues for efficient wastewater treatment. 展开更多
关键词 Ourlago-Kaolin Sodium Montmorillonite Formulated Clay lime Adsorption Acid Dye THERMODYNAMIC
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Preliminary Study on the Treatment Efficiency of Pasteurized Lime Thermal Alkaline Hydrolysis for Excess Activated Sludge and Reduction of Tetracycline Resistance Genes
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作者 Maoxia Chen Qixuan Zhou +3 位作者 Jiayue Zhang Jiaoyang Li Wei Zhang Huan Liu 《Journal of Renewable Materials》 EI 2023年第10期3711-3723,共13页
Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in thi... Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in this study to improve the efficiency of pretreatment method.Direct thermal hydrolysis(TH),pasteurized thermal hydrolysis(PTH),and alkaline pasteurized thermal hydrolysis(PTH+CaO and PTH+NaOH)methods were used to treat EAS.Each method was compared and analyzed in terms of dissolution in ammonium nitrogen(NH_(4)^(+)-N)and soluble COD(SCOD)in EAS.Furthermore,the removal of tetracycline resistance genes(TRGs)and class 1 transposon gene intI1 from EAS was investigated.The NH_(4)^(+)-N and SCOD concentrations in EAS treated by PTH were 1.24 and 2.58 times higher than those of TH.However,the removal efficiency of total TRGs and intI1 between the groups was comparable.The SCOD concentration of the PTH+NaOH group was 4.37 times higher than that of the PTH group,and the removal efficiency of total TRGs was increased by 9.52%compared with that by PTH.The NH_(4)^(+)-N and SCOD concentrations of the PTH+CaO group could reach 85.04%and 92.14%of the PTH+NaOH group,but the removal efficiency of total TRGs by PTH+CaO was 19.78%lower than that by PTH+NaOH.Thus,to reduce the financial cost in actual operation,lime(CaO)can be used instead of a strong alkali(NaOH),and pasteurized steam at 70℃ instead of conventional high-temperature heating to treat EAS.This study provides a reference for the development of alkaline hydrolysis under moderate temperatures along with the removal of TRGs in EAS. 展开更多
关键词 Excess activated sludge tetracycline resistance genes thermal alkaline hydrolysis lime pasteurized thermal hydrolysis
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IsomapVSG-LIME:一种新的模型无关解释方法
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作者 向许 于洪 +1 位作者 张晓霞 王国胤 《智能系统学报》 CSCD 北大核心 2023年第4期841-848,共8页
为了解决局部可解释模型无关的解释(local interpretable model-agnostic explanations,LIME)随机扰动采样方法导致产生的解释缺乏局部忠实性和稳定性的问题,本文提出了一种新的模型无关解释方法IsomapVSG-LIME。该方法使用基于流形学... 为了解决局部可解释模型无关的解释(local interpretable model-agnostic explanations,LIME)随机扰动采样方法导致产生的解释缺乏局部忠实性和稳定性的问题,本文提出了一种新的模型无关解释方法IsomapVSG-LIME。该方法使用基于流形学习的等距映射虚拟样本生成(isometric mapping virtual sample generation,IsomapVSG)方法代替LIME的随机扰动采样方法来生成样本,并使用凝聚层次聚类方法从虚拟样本中选择具有代表性的样本用以训练解释模型;本文还提出了一种新的解释稳定性评价指标—特征序列稳定性指数(features sequence stability index,FSSI),解决了以往评价指标忽略特征的序关系和解释翻转的问题。实验结果表明,本文提出的方法在稳定性和局部忠实性上均优于现有的最新模型。 展开更多
关键词 局部可解释模型无关的解释 机器学习 等距映射虚拟样本生成 凝聚层次聚类 稳定性 局部忠实性 随机扰动采样 特征序列稳定性指数
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基于LIME算法的低照度图像增强方法研究
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作者 刘鹏 《长江信息通信》 2023年第9期72-74,共3页
由于低照度图像存在颜色退化、曝光不足等问题,影响图像质量与信息量,因此文章研究了一种基于LIME算法的低照度图像增强方法。通过合成正常曝光图像与低照度图像的数据集,提取了低照度图像的纹理特征与频域特征,并基于Retinex理论与深... 由于低照度图像存在颜色退化、曝光不足等问题,影响图像质量与信息量,因此文章研究了一种基于LIME算法的低照度图像增强方法。通过合成正常曝光图像与低照度图像的数据集,提取了低照度图像的纹理特征与频域特征,并基于Retinex理论与深度学习建立了低照度图像增强模型。通过使用LIME算法提高模型的可解释性,同时减少模型复杂度,提高模型的透明度。在测试集LOL上,PSNR值为21.898、SSIM值为0.902,证明了该方法的可行性和可靠性。 展开更多
关键词 lime算法 低照度图像 图像增强 方法研究
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基于贝叶斯优化XGBoost的石灰窑气预测
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作者 温后珍 栾仪广 +1 位作者 孟碧霞 陈德斌 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期114-121,共8页
石灰窑是碳酸钙产业的关键生产设备,窑气中的CO_(2)是生产碳酸钙的原料,CO_(2)浓度直接影响碳酸钙产量,然而石灰窑气浓度依靠产品产出后采样化验得到,存在严重的滞后性,无法作为石灰窑在线工艺参数调整的依据。因此提出一种基于贝叶斯... 石灰窑是碳酸钙产业的关键生产设备,窑气中的CO_(2)是生产碳酸钙的原料,CO_(2)浓度直接影响碳酸钙产量,然而石灰窑气浓度依靠产品产出后采样化验得到,存在严重的滞后性,无法作为石灰窑在线工艺参数调整的依据。因此提出一种基于贝叶斯优化的eXtreme Gradient Boosting石灰窑气浓度预测模型BO-XGBoost,根据历史数据预测1 h后的窑气浓度,为生产工艺参数的调整提供依据。该方法首先对石灰窑传感器数据集中的缺失值、异常值进行剔除、插补,然后统一窑气浓度检测历史数据的时间尺度,构成石灰窑气监测数据集,在此基础上提出针对石灰窑气的BO-XGBoost模型。模型经训练后,采用实际生产数据进行测试,并与Light Gradient Boosting Machine(Light-GBM)模型、Category Boosting(Catboost)模型预测结果进行比较,结果表明,所提模型可以实现高维数据集的超参数快速优化,且预测模型有较好的精度,均方根误差(RMSE)达到0.70,平均绝对百分比误差(MAPE)达到2.03%。 展开更多
关键词 石灰窑 石灰窑气 XGBoost模型 贝叶斯优化
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基于前背景特性的逆光交通场景图像增强
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作者 马荣贵 魏子仲 +1 位作者 何逸煦 黄训燕 《无线电工程》 2024年第5期1146-1154,共9页
由于逆光交通场景下采集到的图像存在前景亮度过低、背景亮度失真等特点,导致采集图像清晰度低、信息丢失严重和可识别性差,针对逆光图像前背景的不同特性,研究提出了一种分区域增强方法。对逆光图像使用最大类间方差法(OTSU法)分割图... 由于逆光交通场景下采集到的图像存在前景亮度过低、背景亮度失真等特点,导致采集图像清晰度低、信息丢失严重和可识别性差,针对逆光图像前背景的不同特性,研究提出了一种分区域增强方法。对逆光图像使用最大类间方差法(OTSU法)分割图像的前景和背景;对逆光图像全局使用LIME方法,提升前景亮度的同时保持色彩的失真度;单独将背景部分RGB三个通道上的全局直方图均衡化结果一一映射到对应的限定区间内,提高了背景的对比度;使用Canny算子检测出前背景拼接处的黑边,根据黑边生成3个自适应的滤波模板对黑边进行分步均值滤波处理,消除了黑色边缘,提升了图像的视觉质量。在实验室自建的CHD_B数据集上,所提方法在4种常用客观评价指标上综合占优。实验结果表明,所提出的图像增强算法能有效地消除图像中的逆光现象。 展开更多
关键词 逆光图像 lime 直方图均衡 边缘优化 图像增强
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冻融循环作用下不同含水率灰土的细微观结构与宏观力学性能 被引量:1
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作者 吕晶 赵欢 +1 位作者 张金翼 席培峰 《材料导报》 EI CAS CSCD 北大核心 2024年第7期93-99,共7页
为了探明素土和灰土在不同含水率时细微观结构与宏观力学性能受冻融循环的影响规律,开展了素土和灰土在不同含水率时的冻融循环试验、抗压强度试验和核磁共振试验。结果表明,素土和灰土抗压强度均随含水率的提高而降低;素土和灰土抗压... 为了探明素土和灰土在不同含水率时细微观结构与宏观力学性能受冻融循环的影响规律,开展了素土和灰土在不同含水率时的冻融循环试验、抗压强度试验和核磁共振试验。结果表明,素土和灰土抗压强度均随含水率的提高而降低;素土和灰土抗压强度在同一含水率时均随着冻融循环次数的增加而降低,冻融循环六次时降低率可达到12次时的80%左右;灰土T_(2)谱信号峰值大于素土,T_(2)谱信号峰值随着灰土比例的提高而增大;不同含水率时素土和灰土T_(2)谱面积在冻融循环次数由3次增大至6次的增长率均明显大于6次至12次。 展开更多
关键词 土遗址 灰土 冻融循环 含水率 力学性能 核磁共振
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氧化石墨烯对天然水硬性石灰水化及力学性能的影响
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作者 张彪 刘泓宇 +6 位作者 齐南 王芬 朱建锋 李立 马涛 罗宏杰 施佩 《硅酸盐通报》 CAS 北大核心 2024年第7期2640-2648,共9页
石质文物是一类重要的文化遗产,然而裂隙会导致其产生失稳、渗水、风化等病害,因此,开发一种合适的灌浆材料用于石质文物裂隙修复具有重要意义。本文将氧化石墨烯(GO)掺入天然水硬性石灰(NHL2)制备灌浆材料,采用SEM、TG、XRD和FT-IR等... 石质文物是一类重要的文化遗产,然而裂隙会导致其产生失稳、渗水、风化等病害,因此,开发一种合适的灌浆材料用于石质文物裂隙修复具有重要意义。本文将氧化石墨烯(GO)掺入天然水硬性石灰(NHL2)制备灌浆材料,采用SEM、TG、XRD和FT-IR等测试研究了GO掺量对NHL2水化进程及水化产物的影响,通过力学性能测试和模拟灌浆试验评价了该材料用于石质文物灌浆加固的可行性。结果表明:添加GO可加速NHL2的水化进程,促进规整致密的花状聚集态水化产物的形成;当GO掺量为0.05%(质量分数)时,试样的水化产物含量最多,力学性能最好,28 d抗压强度和抗折强度分别达2.83和1.63 MPa,相比空白试样分别提高了19.91%和23.40%。此外,灌浆材料与砂岩之间具有优异的黏结强度,两者界面结合紧密,兼容性良好。本研究为石质文物的裂隙灌浆加固提供了参考。 展开更多
关键词 天然水硬性石灰 氧化石墨烯 水化产物 微观结构 兼容性 灌浆加固
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喷施石硫合剂对促进沃柑果实着色的影响
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作者 黄其椿 谭颂玥 +8 位作者 汪妮娜 刘福平 刘吉敏 胡承孝 廖惠红 黄宏明 韦持章 陈东奎 曾志康 《湖北农业科学》 2024年第4期73-77,共5页
为验证喷施石硫合剂对沃柑果实着色的效果,在广西南宁市武鸣区城厢镇开展石硫合剂不同处理的试验。结果表明,在沃柑成熟转色关键期(12月30日)喷施石硫合剂对促进沃柑转红和着色有显著促进作用,对促进转红和着色效果最显著的均是单次喷... 为验证喷施石硫合剂对沃柑果实着色的效果,在广西南宁市武鸣区城厢镇开展石硫合剂不同处理的试验。结果表明,在沃柑成熟转色关键期(12月30日)喷施石硫合剂对促进沃柑转红和着色有显著促进作用,对促进转红和着色效果最显著的均是单次喷施石硫合剂1.2波美度,红度值a*比对照(CK)提升了15.24%,柑橘综合着色指数CCI比CK提升了40.07%,均达极显著差异水平。单次喷施石硫合剂0.8波美度,a*和CCI分别比CK提升了11.67%和32.31%。所有喷施石硫合剂的处理均表现出对转红和着色有提升效果。经过田间观察,石硫合剂还对溃疡病、灰霉病、蚜虫、蓟马、蚧壳虫、红蜘蛛等病虫害有良好防效。 展开更多
关键词 沃柑 喷施 石硫合剂 果实着色 病虫害防控
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掺氢氧化钙对超高强混凝土力学性能影响的机理
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作者 朋改非 张贵 +4 位作者 左雪宇 丁宏 陈喜旺 王海迪 刘新建 《材料导报》 EI CAS CSCD 北大核心 2024年第3期110-115,共6页
鉴于含矿物掺合料较多的超高性能混凝土(Ultra-high performance concrete,UHPC)中火山灰反应所需氢氧化钙含量不足的状况,在配制超高强混凝土(UHPC基体)时掺加氢氧化钙,研究其对超高强混凝土力学性能的影响机理。结果表明,超高强混凝... 鉴于含矿物掺合料较多的超高性能混凝土(Ultra-high performance concrete,UHPC)中火山灰反应所需氢氧化钙含量不足的状况,在配制超高强混凝土(UHPC基体)时掺加氢氧化钙,研究其对超高强混凝土力学性能的影响机理。结果表明,超高强混凝土力学性能的改善源于掺入的氢氧化钙与矿物掺合料中的SiO_(2)发生火山灰反应生成C-S-H及C-A-S-H凝胶,且在组合养护(90℃热水养护2 d+250℃干热养护3 d)下,部分C-(A)-S-H凝胶向托勃莫来石与硬硅钙石晶体转变,改善了超高强混凝土的微观结构。 展开更多
关键词 超高强混凝土 氢氧化钙 力学性能 机理
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