检索结果-南通市图书馆

Hyper-parameter optimization of multiple machine learning algorithms for molecular property prediction using hyperopt library

引用

Chinese Journal of Chemical Engineering 2022年第12期52卷 115-125页

作者： jun Zhang qin Wang Weifeng Shen School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China School of Chemistry and Chemical Engineering Chongqing University of Science&TechnologyChongqing 401331China Chongqing Key Laboratory of Theoretical and Computational Chemistry Chongqing 400044China

Due to outstanding performance in cheminformatics,machine learning algorithms have been increasingly used to mine molecular properties and biomedical big *** performance of machine learning models is known to critically depend on the selection of the hyper-parameter ***,many studies either explored the optimal hyper-parameters per the grid searching method or employed arbitrarily selected hyper-parameters,which can easily lead to achieving a suboptimal hyper-parameter *** this study,Hyperopt library embedding with the Bayesian optimization is employed to find optimal hyper-parameters for different machine learning *** drug discovery datasets,including solubility,probe-likeness,h ERG,Chagas disease,tuberculosis,and malaria,are used to compare different machine learning algorithms with ECFP6 *** contribution aims to evaluate whether the Bernoulli Na?ve Bayes,logistic linear regression,Ada Boost decision tree,random forest,support vector machine,and deep neural networks algorithms with optimized hyper-parameters can offer any improvement in testing as compared with the referenced models assessed by an array of metrics including AUC,F1-score,Cohen’s kappa,Matthews correlation coefficient,recall,precision,and *** on the rank normalized score approach,the Hyperopt models achieve better or comparable performance on 33 out 36 models for different drug discovery datasets,showing significant improvement achieved by employing the Hyperopt *** open-source code of all the 6 machine learning frameworks employed in the Hyperopt python package is provided to make this approach accessible to more scientists,who are not familiar with writing code.

关键词： Machine learning Prediction Optimal design Hyper-parameter optimization Hyperopt library

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Instability in Two-Sided Thermocapillary-Buoyancy Convection with Interfacial

引用

Chinese Physics Letters 2020年第1期37卷 19-23页

作者： Guo-Feng Xu Qiu-sheng Liu jun qin Zhi-Qiang Zhu Institute of Mechanics Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

A new model of two-phase thermocapillary-buoyancy convection with phase change at gas-liquid interface in an enclosed cavity subjected to a horizontal temperature gradient is proposed,rather than the previous onesided model without phase *** study the onset of multicellular convection and two inodes of convective instability,and find four different flow *** transition map is compared with the non-phase-change *** numerical results show the stabilizing effect of interfacial phase change on the thermocapillarybuoyancy convection.

关键词： capillary thermocapillary phase

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of refractory period on dynamical range in excitable networks

引用

Chinese Physics B 2019年第12期28卷 378-382页

作者： Ya-qin Dong Fan Wang sheng-jun Wang Zi-Gang Huang School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710119China School of Life Science and Technology Xi'an Jiaotong UniversityXi'an 710049China

Effects of refractory period on the dynamical range in excitable networks are studied by computer simulations and theoretical analysis. The first effect is that the maximum or peak of the dynamical range appears when the largest eigenvalue of adjacent matrix is larger than one. We present a modification of the theory of the critical point by considering the correlation between excited nodes and their neighbors, which is brought by the refractory period. Our analysis provides the interpretation for the shift of the peak of the dynamical range. The effect is negligible when the average degree of the network is large. The second effect is that the dynamical range increases as the length of refractory period increases, and it is independent of the average degree. We present the mechanism of the second effect. As the refractory period increases,the saturated response decreases. This makes the bottom boundary of the dynamical range smaller and the dynamical range extend.

关键词： criticality branching process random network dynamical range

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Nutrient Limitation on Pigments in Thalassiosira weissflogii and Prorocentrum donghaiense

引用

Journal of Integrative Plant Biology 2007年第5期49卷 686-697页

作者： Jian-jun Hou Bang-qin Huang Zhen-Rui Cao Ji-Xin Chen Hua-sheng Hong State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China College of Fisheries Huazhong Agricultural University Wuhan 430070 China Hubei Institute for Nationalities Enshi 445000 China

The response of Prorocentrum donghaiense and Thalassiosira weissfiogii pigments under nitrate （N） and phosphate （P） limitation were studied using HPLC and in vivo fluorescence protocols in batch cultures. For P. donghaiense, the pigment ratio was kept stable under different nutrient conditions from the results of HPLC. For T. weissflogii, there was a lower ratio of chlorophyllide to Chl a during the exponential phase, but the reverse during the stationary phase. Different members of the phytoplankton had different pigments response mechanisms under nutrient limitation. From the results of in vivo fluorescence, the ratio of peridinin to Chl a for P. donghaiense increased in nutrient-free culture, while it was kept stable for nutrient-limited cultures during the exponential phase. For T. weissflogii, the ratio of fucoxanthin to Chl a for each culture increased during the exponential phase, but the ratio under N limitation was apparently lower than that for P limitation during the stationary phase. The results indicate that both pigment ratios from HPLC and in vivo fluorescence of To weissflogii were changed greatly under different nutrient conditions, which suggests that both ratios could be used as indicators of algal physiological status in different nutrient conditions.

关键词： HPLC in vivo fluorescence nutrient limitation pigments Prorocentrum donghaiense Thalassiosira weissflogii.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Special Issue on Future Digital Design and Manufacturing:Embracing Industry 4.0 and Beyond-Part Ⅱ

引用

Chinese Journal of Mechanical Engineering 2017年第5期30卷 1045-1046页

作者： sheng-Feng qin Kai Cheng School of Design Northumbria University College of Engineering Design and Physical SciencesBrunel University London

Digital design and manufacturing have been under pinned by digital modeling, simulation, and automation controls for decades. Under the new market requirement of mass customized products and services, the advancements in artificial intelligence （AI）, smart technology, virtual reality （VR）, big data, digital twin, robotics and human-centered design are becoming driving forces for the development of future digital design and manufacturing. This special issue focuses on the future digital design and manufacturing especially under the Industry 4.0 framework and beyond. This editorial introduces the papers in this special issue, which linked to the International Workshop on Digital Design and Manufacturing Technologies - Embracing Industry 4.0 and Beyond at Northumbria University in Newcastle, UK, held on 12-13 April 2016. In the Part I of the issue [1], there are 13 papers published in 2016, Vol- ume 29, No 6 of the Chinese Journal of Mechanical Engineering （this journal）.

关键词： Design In Special Issue on Future Digital Design and Manufacturing:Embracing Industry 4.0 and Beyond-Part

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Parameter study of sinter waste heat recovery in vertical tank based on energy and exergy analysis

引用

Journal of Iron and Steel Research International 2020年第1期27卷 22-32页

作者： jun-sheng Feng sheng Zhang Hui Dong Gang Pei School of Environment and Energy Engineering Anhui Jianzhu UniversityHefei 230026AnhuiChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230026AnhuiChina

The parameter study of sinter waste heat recovery in vertical tank was conducted numerically by using energy and exergy analysis,and the experimental data obtained from a homemade experimental apparatus was applied to verify the reliability of numerical *** on the first and second laws of thermodynamics,the effects of flow rate of cooling air(FRCA)and inlet temperature of cooling air(ITCA),as well as the inner diameter of cooling section(IDCS)and height of cooling section(HCS),on the sinter cooling process were analyzed in *** results show that the average deviation between the experimental data and calculation values is 4.93%,and the model reliability is *** enthalpy exergy of outlet air tends to increase first and then decrease with increasing the FRCA and ITCA,while increasing the IDCS only leads to the increase in enthalpy exergy of outlet *** a given operational condition,the enthalpy exergy of outlet air can reach a maximum value with increasing the *** vertical tank could obtain the maximum enthalpy exergy of outlet air through the adjustments of FRCA and ITCA,as well as the HCS.

关键词： Sinter Waste heat recovery Porous medium-Energy analysis Exergy analysis Vertical bank

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

One-Pot Synthesis of Bismuth Basic Nitrate-Bi_(2)MoO_(6) Photocatalyst for Selective Oxidation of Toluene

引用

Chinese Journal of Structural Chemistry 2022年第12期41卷 25-32页

作者： Tian-qin Zeng Lang Chen Bing-Hao Wang sheng Tian Zhang-jun Bai Xiong Wang jun-Kang Guo Shuang-Feng Yin Advanced Catalytic Engineering Research Center of the Ministry of Education College of Chemistry and Chemical EngineeringState Key Laboratory of Chemo/Biosensing and ChemometricsHunan UniversityChangsha 410082China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

The key issues to improve the performance of photocatalysts for selective oxidation of toluene are promoting the migration and separation of charge carrier,and enhancing the generation of active oxygen *** is known that the construction of compact heterojunction is an efficient protocol to inhibit photogenerated electron-hole *** this work,a 2D-2D[Bi_(6)O_(6)(OH)_(3)](NO_(3))3·1.5H2O-Bi_(2)MoO_(6)(denoted as BBN-BMO)composite heterojunction has been prepared by one-step hydrothermal method for the first *** tetragonal phase BBN in the composite plays the role of transferring electrons from the visible light activated orthorhombic phase BMO and promoting the generation of active·O_(2)^(-),the holes left in BMO are used to activate toluene and produce benzyl radical,thus greatly improving the photocatalytic performance for selective oxidation of *** toluene conversion rate of BBN-BMO is 3466μmol·g^(-1)·h^(-1),which is three times that of pure *** selectivity to benzalde-hyde is 94.2%.In addition,reasonable mechanism has been speculated based on a series of control experiments.

关键词： Bi_(2)MoO_(6) basic bismuth nitrate heterojunction photocatalysis selective oxidation of toluene

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

引用

Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun Chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Gluon saturation and baryon stopping in the SPS, RHIC, and LHC energy regions

引用

Chinese Physics C 2012年第2期36卷 136-141页

作者： LI Shuang FENG sheng-qin College of Science China Three Gorges UniversityYichang 443002China Key Laboratory of Quark and Lepton Physics(Huazhong Normal University) Ministry of EducationWuhan 430079China School of Physics and Technology Wuhan UniversityWuhan 430072China

A new geometrical scaling method with a gluon saturation rapidity limit is proposed to study the gluon saturation feature of the central rapidity region of relativistic nuclear collisions. The net-baryon number is essentially transported by valence quarks that probe the saturation regime in the target by multiple scattering. We take advantage of the gluon saturation model with geometric scaling of the rapidity limit to investigate net baryon distributions, nuclear stopping power and gluon saturation features in the SPS and RHIC energy regions. Predictions for net-baryon rapidity distributions, mean rapidity loss and gluon saturation feature in central Pb＋Pb collisions at the LHC are made in this paper.

关键词： gluon saturation geometrical scaling net-baryon distributions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

引用

Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：