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Optimized Deep Feature Learning with Hybrid Ensemble Soft Voting for Early Breast Cancer Histopathological Image Classification
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作者 Roseline Oluwaseun Ogundokun Pius Adewale Owolawi Chunling Tu 《Computers, Materials & Continua》 2025年第9期4869-4885,共17页
Breast cancer is among the leading causes of cancer mortality globally,and its diagnosis through histopathological image analysis is often prone to inter-observer variability and misclassification.Existing machine lea... Breast cancer is among the leading causes of cancer mortality globally,and its diagnosis through histopathological image analysis is often prone to inter-observer variability and misclassification.Existing machine learning(ML)methods struggle with intra-class heterogeneity and inter-class similarity,necessitating more robust classification models.This study presents an ML classifier ensemble hybrid model for deep feature extraction with deep learning(DL)and Bat Swarm Optimization(BSO)hyperparameter optimization to improve breast cancer histopathology(BCH)image classification.A dataset of 804 Hematoxylin and Eosin(H&E)stained images classified as Benign,in situ,Invasive,and Normal categories(ICIAR2018_BACH_Challenge)has been utilized.ResNet50 was utilized for feature extraction,while Support Vector Machines(SVM),Random Forests(RF),XGBoosts(XGB),Decision Trees(DT),and AdaBoosts(ADB)were utilized for classification.BSO was utilized for hyperparameter optimization in a soft voting ensemble approach.Accuracy,precision,recall,specificity,F1-score,Receiver Operating Characteristic(ROC),and Precision-Recall(PR)were utilized for model performance metrics.The model using an ensemble outperformed individual classifiers in terms of having greater accuracy(~90.0%),precision(~86.4%),recall(~86.3%),and specificity(~96.6%).The robustness of the model was verified by both ROC and PR curves,which showed AUC values of 1.00,0.99,and 0.98 for Benign,Invasive,and in situ instances,respectively.This ensemble model delivers a strong and clinically valid methodology for breast cancer classification that enhances precision and minimizes diagnostic errors.Future work should focus on explainable AI,multi-modal fusion,few-shot learning,and edge computing for real-world deployment. 展开更多
关键词 Breast cancer classification ensemble learning deep learning bat swarm optimization HISTOPATHOLOGY soft voting
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Confined soft carbon in hard carbon with enhanced ion transport kinetics as anode for high-rate and stable potassium-ion batteries 被引量:2
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作者 Yong Li Aoyang Zhu +5 位作者 Guodong Peng Jun He Hongqiang Li Dedong Jia Jieshan Qiu Xiaojun He 《Journal of Energy Chemistry》 2025年第4期97-105,共9页
Biomass-derived hard carbon is becoming promising anodes for potassium-ion batteries(PIBs)thanks to their resource abundance.Yet,it is a big challenge to improve the charge carrier kinetics of the disordered carbon la... Biomass-derived hard carbon is becoming promising anodes for potassium-ion batteries(PIBs)thanks to their resource abundance.Yet,it is a big challenge to improve the charge carrier kinetics of the disordered carbon lattice in hard carbon.Herein,confined pitch-based soft carbon in pollen-derived hard carbon(PSC/PHC)is synthesized by vapor deposition strategy as anodes for PIBs.The ordered pitch-based soft carbon compensates for the short-range electron conduction in hard carbon to enhance the charge transfer kinetics,and the externally disordered pollen-derived hard carbon alleviates the volume change of soft carbon during cycling.Benefiting from the synergistic effect of soft and hard carbon,as well as the reinforced structure of order-in-disordered carbon,the PSC/PHC obtained with deposition time of 0.5 h(PSC/PHC-0.5)displays an excellent rate capability(148.7 mAh g^(-1)at 10 A g^(-1))and superb cycling stability(70%retention over 2000 cycles at 1 A g^(-1)).This work offers a unique insight in tuning the microcrystalline structure of soft-hard carbon anode for advanced PIBs. 展开更多
关键词 Biomass-derived hard carbon Pitch-based soft carbon Microcrystalline regulation engineering Order-in-disordered carbon Potassium-ion batteries
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Various classification methods for diabetes mellitus in the management of blood glucose control 被引量:1
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作者 Qing Jiang Yun Hu Jian-Hua Ma 《World Journal of Diabetes》 2025年第5期1-7,共7页
In the era of precision medicine,the classification of diabetes mellitus has evolved beyond the traditional categories.Various classification methods now account for a multitude of factors,including variations in spec... In the era of precision medicine,the classification of diabetes mellitus has evolved beyond the traditional categories.Various classification methods now account for a multitude of factors,including variations in specific genes,type ofβ-cell impairment,degree of insulin resistance,and clinical characteristics of metabolic profiles.Improved classification methods enable healthcare providers to formulate blood glucose management strategies more precisely.Applying these updated classification systems,will assist clinicians in further optimising treatment plans,including targeted drug therapies,personalized dietary advice,and specific exercise plans.Ultimately,this will facilitate stricter blood glucose control,minimize the risks of hypoglycaemia and hyperglycaemia,and reduce long-term complications associated with diabetes. 展开更多
关键词 Diabetes classification Glycaemic control Personalised treatment soft clustering Precision medicine
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3D printing of hard/soft switchable hydrogels
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作者 Guofeng Liu Pengcheng Xia +4 位作者 Weicheng Kong Tianhong Qiao Yuan Sun Wenjie Ren Yong He 《International Journal of Extreme Manufacturing》 2025年第4期248-263,共16页
3D(three-dimensional)printing of soft/tough hydrogels has been widely used in flexible electronics,regenerative medicine,and other fields.However,due to their loose crosslinking,strong hydration and plasticizing effec... 3D(three-dimensional)printing of soft/tough hydrogels has been widely used in flexible electronics,regenerative medicine,and other fields.However,due to their loose crosslinking,strong hydration and plasticizing effect of solvent(typically water)and susceptibility to swelling,the printed hydrogels always suffer from bearing compressive stress and shear stress.Here we report a 3D photo-printable hard/soft switchable hydrogel composite which is enabled by the phase transition(liquid/solid transition)of supercooled hydrated salt solution(solvents)within hydrogel.In hard status,it achieved a hardness of 86.5 Shore D(comparable to hard plastics),a compression strength of 81.7 MPa,and Young’s modulus of 1.2 GPa.These mechanical property parameters far exceed those of any currently 3D printed hydrogels.The most interesting thing is that the soft/hard states are easily switchable and this process can be repeated for many times.In the supercooled state,the random arrangement of liquid solvent molecules within hydrogels makes it as soft as conventional hydrogels.Upon artificial seeding of the crystal nucleus,the solvent in hydrogel undergoes rapid crystallization,resulting in the in-situ formation of numerous rigids,ordered rod-like nanoscale crystals uniformly embedded within the hydrogel matrix.This hierarchical structure remarkably enhances the Young’s modulus from kPa to GPa.Furthermore,the softness of hydrogel can be restored by heating and then cooling down to recover the supercooled state of the solvent.Taking advantage of soft/hard status switching,the hydrogel can conform to complex surface morphologies in its soft state and subsequently freeze that shape through crystallization,enabling rapid mold fabrication.Moreover,a shape fixation and recyclable smart hydrogel medical plaster bandage was also developed,capable of conforming the limb shapes and providing adequate support for the bone fracture patients after 10 min of crystallization.Our work suggests a bright future for the direct use of hard hydrogel as a robust industrial material. 展开更多
关键词 3D printing soft/hard switchable hydrogel supercooled solution CRYSTALLIZATION smart plaster bandage
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Strength Deterioration Characteristics of Soft and Hard Interbedded Rock Masses in Three Gorges Reservoir Area Induced by Wetting-Drying Cycles
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作者 Qiong Wu Di Wang +7 位作者 Huiming Tang Jintao Kang Hongming Luo Yuxin Liu Shiyu Li Bo Zhang Zhiqi Liu Zhiwei Lin 《Journal of Earth Science》 2025年第5期1948-1962,共15页
The rock masses in the hydro-fluctuation zone of reservoir banks sustain wettingdrying cycles(WDC),thereby affecting the stability of the reservoir bank slope.In this paper,rock masses with argillaceous siltstone and ... The rock masses in the hydro-fluctuation zone of reservoir banks sustain wettingdrying cycles(WDC),thereby affecting the stability of the reservoir bank slope.In this paper,rock masses with argillaceous siltstone and silty mudstone interbedded in Badong Formation were taken as the research object to investigate the variation of strength parameters of soft and hard interbedded rock masses with WDC and dip angle through laboratory experiments and numerical experiments.Some attempts were made to reveal the mechanical properties deterioration mechanism of interbedded rock masses by quantitatively analyzing the contribution of strength parameters deterioration of hard rocks,soft rocks,and bedding planes to the strength parameters deterioration of rock masses.The results indicate that the logarithmic function could be used to describe the deterioration of each strength parameter of both argillaceous siltstone and silty mudstone and bedding plane with the number of WDC.The strength parameters of interbedded rock masses decrease as the number of WDC increases,with the largest decrease after the first cycle and then slowing down in the later cycles.The strength parameters initially decrease and then increase as the dip angles increase.The impact of deteriorated strength parameters of bedding planes and rocks on the deterioration of strength parameters of interbedded rock masses differs significantly with the dip angle,which can be divided into four typical ranges of different controlling factors. 展开更多
关键词 strength deterioration wetting-drying cycles soft and hard interbedded rock mass numerical simulations contribution degree engineering geology
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Phase classification of high entropy alloys with composition,common physical,elemental-property descriptors and periodic table representation
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作者 Shuai LI Jia YANG +2 位作者 Shu LI Dong-rong LIU Ming-yu ZHANG 《Transactions of Nonferrous Metals Society of China》 2025年第6期1855-1874,共20页
Phase classification has a clear guiding significance for the design of high entropy alloys.For mutually exclusive and non-mutually exclusive classifications,the composition descriptors,commonly used physical paramete... Phase classification has a clear guiding significance for the design of high entropy alloys.For mutually exclusive and non-mutually exclusive classifications,the composition descriptors,commonly used physical parameter descriptors,elemental-property descriptors,and descriptors extracted from the periodic table representation(PTR)by the convolutional neural network were collected.Appropriate selection among features with rich information is helpful for phase classification.Based on random forest,the accuracy of the four-label classification and balanced accuracy of the five-label classification were improved to be 0.907 and 0.876,respectively.The roles of the four important features were summarized by interpretability analysis,and a new important feature was found.The model extrapolation ability and the influence of Mo were demonstrated by phase prediction in(CoFeNiMn)_(1-x)Mo_(x).The phase information is helpful for the hardness prediction,the classification results were coupled with the PTR of hardness data,and the prediction error(the root mean square error)was reduced to 56.69. 展开更多
关键词 high entropy alloy phase classification feature engineering periodic table representation convolutional neural network hardness prediction
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LEARNING ALGORITHM OF FEEDFORWARD NEURAL NETWORK WITH HARD LIMITER USED FOR CLASSIFICATION
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作者 张兆宁 孙雅明 毛鹏 《Transactions of Tianjin University》 EI CAS 1999年第2期14-18,共5页
A learning algorithm based on a hard limiter for feedforward neural networks (NN) is presented,and is applied in solving classification problems on separable convex sets and disjoint sets.It has been proved that the a... A learning algorithm based on a hard limiter for feedforward neural networks (NN) is presented,and is applied in solving classification problems on separable convex sets and disjoint sets.It has been proved that the algorithm has stronger classification ability than that of the back propagation (BP) algorithm for the feedforward NN using sigmoid function by simulation.What is more,the models can be implemented with lower cost hardware than that of the BP NN.LEARNIN 展开更多
关键词 hard limiter separable convex sets HYPERPLANE feedforward NN classification learning algorithm
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Pitch-derived soft carbon composite with hard carbon fibers for high-rate and long-cycling K^(+) storage
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作者 PENG Jiao WANG Rui +3 位作者 JIN Jun HE Bei-bei GONG Yan-sheng WANG Huan-wen 《西北师范大学学报(自然科学版)》 CAS 2024年第6期53-62,I0003,共11页
Potassium-ion batteries(KIBs)have been seen as a competitive alternative to lithium-ion batteries(LIBs)due to their natural abundance,low cost and rocking chair-like operating mechanism similar to LIBs.Soft carbon has... Potassium-ion batteries(KIBs)have been seen as a competitive alternative to lithium-ion batteries(LIBs)due to their natural abundance,low cost and rocking chair-like operating mechanism similar to LIBs.Soft carbon has a lower voltage plateau compared to hard carbon and an easily modulated lattice structure compared to graphite,which provides particular advantages in KIBs anodes.Pitch has attracted much attention as a simple,readily available and inexpensive precursor for soft carbon,but its structure is easily damaged during cycling.Herein,the flexible film Pitch@CNF are prepared by uniformly winding reticulated carbon fibers on the surface of pitch-soft carbon via electrostatic spinning technique,which not only enables the pitch to maintain its structure well during cycling and withstand the volume expansion upon K^(+) insertion,but also is conducive to ionic transport of the three-dimensional reticulated structure.Meanwhile,the abundant pores on the carbon fibers can provide more K^(+) active sites.The prepared flexible self-supporting films can be used directly as electrodes without the addition of binders and conductive agents.The reversible capacity is 290 mAh·g^(-1)at a current density of 0.1 A·g^(-1),and the capacity retention rate is 83%after 500 cycles. 展开更多
关键词 soft carbon hard carbon potassium ion capacitors carbon fibers PITCH
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Generalized Normalized Euclidean Distance Based Fuzzy Soft Set Similarity for Data Classification 被引量:2
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作者 Rahmat Hidayat Iwan Tri Riyadi Yanto +2 位作者 Azizul Azhar Ramli Mohd Farhan Md.Fudzee Ansari Saleh Ahmar 《Computer Systems Science & Engineering》 SCIE EI 2021年第7期119-130,共12页
Classification is one of the data mining processes used to predict predetermined target classes with data learning accurately.This study discusses data classification using a fuzzy soft set method to predict target cl... Classification is one of the data mining processes used to predict predetermined target classes with data learning accurately.This study discusses data classification using a fuzzy soft set method to predict target classes accurately.This study aims to form a data classification algorithm using the fuzzy soft set method.In this study,the fuzzy soft set was calculated based on the normalized Hamming distance.Each parameter in this method is mapped to a power set from a subset of the fuzzy set using a fuzzy approximation function.In the classification step,a generalized normalized Euclidean distance is used to determine the similarity between two sets of fuzzy soft sets.The experiments used the University of California(UCI)Machine Learning dataset to assess the accuracy of the proposed data classification method.The dataset samples were divided into training(75%of samples)and test(25%of samples)sets.Experiments were performed in MATLAB R2010a software.The experiments showed that:(1)The fastest sequence is matching function,distance measure,similarity,normalized Euclidean distance,(2)the proposed approach can improve accuracy and recall by up to 10.3436%and 6.9723%,respectively,compared with baseline techniques.Hence,the fuzzy soft set method is appropriate for classifying data. 展开更多
关键词 soft set fuzzy soft set classification normalized euclidean distance SIMILARITY
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Deformation characteristics and damage ontologies of soft and hard composite rock masses under impact loading
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作者 LI Jinhua ZHANG Tianyu +3 位作者 WU Baolin SU Peili YANG Yang WANG Pan 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1715-1727,共13页
As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study ... As one of the most common occurring geological landforms in deep rock formations, the dynamic mechanical properties of layered composite rock bodies under impact loading have been widely studied by scholars. To study the dynamic properties of soft and hard composite rocks with different thickness ratios, this paper utilizes cement, quartz sand and gypsum powder to construct soft and hard composite rock specimens and utilizes a combination of indoor tests, numerical calculations, and theoretical analyses to investigate the mechanical properties of soft and hard composite rock bodies. The test results reveal that:(1) When the proportion of hard rock increases from 20% to 50%, the strength of the combined rock body increases by 69.14 MPa and 87 MPa when the hard rock face and soft rock face are loaded, respectively;however, when the proportion of hard rock is the same, the compressive strength of the hard rock face impact is 9%-17% greater than that of the soft rock face impact;(2) When a specimen of soft and hard combined rock body is subjected to impact loading, the damage mode involves mixed tension and shear damage, and the cracks generally first appear at the ends of the specimen, then develop on the laminar surface from the impact surface, and finally end in the overall damage of the soft rock part. The development rate and the total number of cracks in the same specimen when the hard rock face is impacted are significantly greater than those when the soft rock face is impacted;(3) By introducing Weibull’s statistical strength theory to establish the damage variables of soft-hard combined rock bodies, combined with the DP strength criterion, the damage model and the Kelvin body are concatenated to obtain a statistical damage constitutive model, which can better fit the full stress-strain curve of soft-hard combined rock body specimens under a single impact load. 展开更多
关键词 soft and hard composite rock mass Dynamic properties Split Hopkinson pressure bar(SHPB) Numerical simulation Intrinsic damage model
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On the Soft Law Governance of Environmental Rights Protection in the Belt and Road Initiative
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作者 HU Xiaofan 《The Journal of Human Rights》 2025年第3期749-767,共19页
Environmental rights are an important part of General Secretary Xi Jinping’s important discourses on respecting and protecting human rights.Soft law has played a significant role in the integrated development of the ... Environmental rights are an important part of General Secretary Xi Jinping’s important discourses on respecting and protecting human rights.Soft law has played a significant role in the integrated development of the theories of environmental rights and human rights.At the practical level,the soft law cooperation documents of the Belt and Road Initiative(BRI)have established general principles for the protection of environmental rights,policies for addressing climate change,standards for green investment and financing,and obligations for multinational corporations to protect the environment,making a contribution to the development and protection of environmental rights.In the future process of global environmental governance,it is necessary to start with the BRI’s soft law documents to further clarify the specific protection standards for environmental rights and promote the transformation of soft law into binding bilateral or multilateral agreements at the international level.In addition,it is essential to urge governments and enterprises to fulfill their due diligence obligations for environmental protection and strengthen information disclosure by emphasizing public interest responsibilities.Efforts should also be made to improve the environmental compliance systems of“going global”enterprises and enhance government supervision over corporate accountability for environmental rights.A corporate environmental protection accountability mechanism should be established,so as to actively promote global environmental governance in a more just and reasonable direction. 展开更多
关键词 co-construction of the Belt and Road Initiative environmental rights human rights soft law governance hard law
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Constitutive model for methane desorption and diffusion based on pore structure differences between soft and hard coal 被引量:9
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作者 Liu Yanwei Wang Dandan +2 位作者 Hao Fuchang Liu Mingju Mitri Hani S. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期937-944,共8页
This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore struct... This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore structure is constructed by considering the difference in characteristics between soft coal and hard coal.The analytical solution is then derived, that is, the quantitative relationship between gas diffusion rate(Qt/Q_∞) and diffusion time(t), The pore structure parameters of soft coal and hard coal from Juji coal mine are determined. Gas diffusion rules are numerically calculated and investigated by physical simulation methods. Lastly, the applicability of this model is verified. The results show that the homogeneous model only applies to the gas diffusion process of hard coal during the initial 10 min. The calculation results from this model and the physical experimental results of soft coal and hard coal are nearly identical during the initial 30 min. 展开更多
关键词 soft and hard coal Gas diffusion PORE structure CONSTITUTIVE models Physical simulation
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Comparison of Starch Granule Size Distribution Between Hard and Soft Wheat Cultivars in Eastern China 被引量:9
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作者 LI Wen-yang YAN Su-hui YIN Yah-ping LIYong LIANG Tai-bo GU Feng DAI Zhong-min WANG Zhen-lin 《Agricultural Sciences in China》 CAS CSCD 2008年第8期907-914,共8页
Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Ex... Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Experimental Station of Shandong Agricultural University, Taian, Shandong, China, were examined in this study. The granule size distribution and amylose contents in wheat grains were studied and compared, and relationships between the properties were identified. A clear bimodal distribution of granule size was shown in all wheat cultivars. Volume distribution of starch granules shows the typical bimodal with peak values in the ranges of 5.6-6.1μm and 20.7-24.9μm, respectively. Also, granule surface area distribution was bimodal with peak values in the ranges of 2.4-3.2μm and 20.7-24.9μm, respectively. Number distribution of granules was a typical population with a peak value in the range of 0.54-1.05μm. Contributions from the granules 〈 2.8μm and 〈 9.9μm to the total volume were in the ranges of 94.2-95.1% and 99.7-99.9% of total number, respectively. Proportions of granules〈2.8μm, 2.8-9.9μm, 9.9-22.8μm, and 22.8-42.8μm were in the ranges of 12.9-14.3%, 28.4-31.1%, 33.5-35.6%, and 19.7-22.7% for hard wheat, and 10.3-13.9%, 26.6-28.1%, 32.7-34.6%, and 24.2-27% for soft wheat. Hard wheat had greater B-type granules ( 〈 9.9μm), and had fewer granules of 22.8-42.8μm than soft wheat. Amylose content was positively related to volume percentage of granules 22.8-42.8μm, and negatively related to volume percentage of granules 2.8-22.8μm. 展开更多
关键词 wheat (Triticum aestivum L.) starch granule size distribution AMYLOSE hard wheat soft wheat
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A solvothermal pre-oxidation strategy converting pitch from soft carbon to hard carbon for enhanced sodium storage 被引量:21
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作者 Jing Wang Lei Yan +4 位作者 Binhua Liu Qingjuan Ren Linlin Fan Zhiqiang Shi Qingyin Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期580-583,共4页
Due to its low cost and easy availability, the pitch is considered a promising precursor for soft carbon anodes. However, pitch-derived soft carbon shows a high graphitization degree and small interlayer spacing, resu... Due to its low cost and easy availability, the pitch is considered a promising precursor for soft carbon anodes. However, pitch-derived soft carbon shows a high graphitization degree and small interlayer spacing, resulting in its much lower sodium storage performance than hard carbon. We propose a novel preoxidation strategy to introduce additional oxygen atoms into the low-cost soft carbon precursor pitch to fabricate a defect-rich and large-interlayer spacing hard carbon anode(HPP-1100). Compared with the direct pyrolysis of pitch carbon, the sodium storage capacity of HPP-1100 is significantly improved from 120.3 m Ah/g to 306.7 m Ah/g, with an excellent rate and cycling capability(116.5 m Ah/g at 10 C). Moreover, when assorted with an O_(3)-Na(NiFeMn)1/3O_(2)cathode, the full cell delivers a high reversible capacity of 274.0 m Ah/g at 0.1 C with superb cycle life. This work provides a new solution for realizing the application of low-cost pitch anodes in Na-ion batteries. 展开更多
关键词 soft carbon hard carbon Solvothermal pre-oxidation Na-ion battery PITCH
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Excavation-induced microseismicity and rockburst occurrence:Similarities and differences between deep parallel tunnels with alternating soft-hard strata 被引量:15
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作者 FENG Guang-liang CHEN Bing-rui +3 位作者 JIANG Quan XIAO Ya-xun NIU Wen-jing LI Peng-xiang 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第2期582-594,共13页
Excavation-induced microseismicity and rockburst occurrence in deep underground projects provide invaluable information that can be used to warn rockburst occurrence,facilitate rockburst mitigation procedures,and anal... Excavation-induced microseismicity and rockburst occurrence in deep underground projects provide invaluable information that can be used to warn rockburst occurrence,facilitate rockburst mitigation procedures,and analyze the mechanisms responsible for their occurrence.Based on the deep parallel tunnels with the maximum depth of 1890 m created as part of the Neelum–Jhelum hydropower project in Pakistan,similarities and differences on excavation-induced microseismicity and rockburst occurrence between parallel tunnels with soft and hard alternant strata are studied.Results show that a large number of microseismic(MS)events occurred in each of the parallel tunnels during excavation.Rockbursts occurred most frequently in certain local sections of the two tunnels.Significant differences are found in the excavation-induced microseismicity(spatial distribution and number of MS events,distribution of MS energy,and pattern of microseismicity variation)and rockbursts characteristics(the number and the spatial distribution)between the parallel tunnels.Attempting to predict the microseismicity and rockburst intensities likely to be encountered in subsequent tunnel based on the activity encountered when the parallel tunnel was previously excavated will not be an easy or accurate procedure in deep tunnel projects involving complex lithological conditions. 展开更多
关键词 MICROSEISMICITY ROCKBURST soft and hard alternant strata deep parallel tunnels Neelum–Jhelum hydropower project
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Mixed-Weights Least-Squares Stable Predictive Control Algorithm with Soft and Hard Constraints 被引量:3
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作者 周立芳 邵之江 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第5期565-570,共6页
Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in... Mixed-weight least-squares (MWLS) predictive control algorithm, compared with quadratic programming (QP) method, has the advantages of reducing the computer burden, quick calculation speed and dealing with the case in which the optimization is infeasible. But it can only deal with soft constraints. In order to deal with hard constraints and guarantee feasibility, an improved algorithm is proposed by recalculating the setpoint according to the hard constraints before calculating the manipulated variable and MWLS algorithm is used to satisfy the requirement of soft constraints for the system with the input constraints and output constraints. The algorithm can not only guarantee stability of the system and zero steady state error, but also satisfy the hard constraints of input and output variables. The simulation results show the improved algorithm is feasible and effective. 展开更多
关键词 mixed-weight least-squares predictive control soft constraints hard constraints FEASIBILITY
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Integrated simulation and monitoring to analyze failure mechanism of the anti-dip layered slope with soft and hard rock interbedding 被引量:5
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作者 Jinduo Li Yuan Gao +5 位作者 Tianhong Yang Penghai Zhang Yong Zhao Wenxue Deng Honglei Liu Feiyue Liu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第9期1147-1164,共18页
The significant difference between the mechanical properties of soft rock and hard rock results in the complexity of the failure mode of the anti-dip layered slope with soft and hard rock interbedding.In order to reve... The significant difference between the mechanical properties of soft rock and hard rock results in the complexity of the failure mode of the anti-dip layered slope with soft and hard rock interbedding.In order to reveal the landslide mechanism,taking the north slope of Fushun West Open-pit Mine as an example,this paper analyzed the failure mechanism of different landslides with monitoring and field surveys,and simulated the evolution of landslides.The study indicated that when the green mudstone(hard rock)of the anti-dip slope contains siltized intercalations(soft rock),the existence of weak layers not only aggravates the toppling deformation of anti-dip layered slope with high dip,but also causes the shear failure of anti-dip layered slope with stable low dip.The shear failure including subsidence induced sliding and wedge failure mainly exists in the unloading zone of the slope.Its failure depth and failure time were far less than that of toppling failure.In terms of the development characteristics of deformation,toppling deformation has the long-term and progressive characteristics,but shear failure deformation has the abrupt and transient characteristics.This study has deepened the understanding of such slope landslide mechanism,and can provide reference for similar engineering. 展开更多
关键词 Anti-dip layered slope soft and hard rock interbedding Toppling failure Wedge failure Fushun West Open-pit Mine
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Influence of confining stress on fracture characteristics and cutting efficiency of TBM cutters conducted on soft and hard rock 被引量:2
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作者 刘京铄 曹平 +1 位作者 刘杰 蒋喆 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1947-1955,共9页
Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000)... Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000) designed and manufactured in Central South University(China). Results are obtained by performing analysis on the fracture scopes of cement and granite plates,the characteristics of cutting force in cutting processes and the cutting efficiency. Firstly, the increase of latitude fracture scope and the decrease of longitude fracture scope are both more notable in the tests conducted on cement plates subjected to the increasing confining stresses; secondly, the increase tendency of peak penetration forces obtained from tests conducted on granite plates is more obvious, however, the increase tendencies of average penetration forces achieved from cement and granite plates are close to each other; thirdly, the cutting efficiency could be improved by increasing the spacing between cutters when the confining stress which acts on soft and hard rock increases in a certain degree, and the cutting efficiency of soft rock is more sensitive to the varying confining stresses. 展开更多
关键词 triaxial testing machine numerical study tunnel boring machine(TBM) cutter confining stress soft and hard rock cutting efficiency
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Theoretical study on stability evolution of soft and hard interbedded bedding reservoir slopes 被引量:1
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作者 WU Qiong ZHANG Bo +3 位作者 TANG Hui-ming WANG di LIU Zhi-qi LIN Zhi-wei 《Journal of Mountain Science》 SCIE CSCD 2023年第9期2744-2755,共12页
Soft and hard interbedded bedding rock slopes,which is prone to failure,are widely distributed in the Three Gorges Reservoir,China.Limit equilibrium method(LEM)is commonly used to analyze the stability of bedding rock... Soft and hard interbedded bedding rock slopes,which is prone to failure,are widely distributed in the Three Gorges Reservoir,China.Limit equilibrium method(LEM)is commonly used to analyze the stability of bedding rock slopes that have a single failure plane.However,this method cannot accurately estimate the stability of soft and hard interbedded bedding reservoir slopes because the strength parameters of a soft and hard interbedded rock mass vary spatially along the bedding plane and deteriorate with time due to periodic fluctuations of reservoir level.A modified LEM is proposed to evaluate the stability evolution of soft and hard interbedded bedding reservoir slopes considering the spatial variation and temporal deterioration of shear strength parameters of rock masses and bedding planes.In the modified LEM,the S-curve model is used to define the spatial variation of shear strength parameters,and general deterioration equations of shear strength parameters with the increasing number of wettingdrying cycles(WDC)are proposed to describe the temporal deterioration.Also,this method is applied to evaluate the stability evolution of a soft and hard interbedded bedding reservoir slope,located at the Three Gorges Reservoir.The results show that neglecting the spatial variation and temporal deterioration of shear strength parameters may overestimate slope stability.Finally,the modified LEM provides useful guidance to reasonably evaluate the long-term stability of soft and hard interbedded bedding reservoir slopes in reservoir area. 展开更多
关键词 soft and hard interbedded rock slope Limit equilibrium method Spatial variation Wetting and drying cycles Plane failure Stability evolution
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Experimental analysis of pore structure and fractal characteristics of soft and hard coals with same coalifcation 被引量:1
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作者 Barkat Ullah Yuanping Cheng +3 位作者 Liang Wang Weihua Yang Izhar Mithal Jiskani Biao Hu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第4期107-121,共15页
Accurate and quantitative investigation of the physical structure and fractal geometry of coal has important theoretical and practical signifcance for coal bed methane(CBM)development and the prevention of dynamic dis... Accurate and quantitative investigation of the physical structure and fractal geometry of coal has important theoretical and practical signifcance for coal bed methane(CBM)development and the prevention of dynamic disasters such as coal and gas outbursts.This study investigates the pore structure and fractal characteristics of soft and hard coals using nitrogen and carbon dioxide(N_(2)/CO_(2))adsorption.Coal samples from Pingdingshan Mine in Henan province of China were collected and pulverized to the required size(0.20–0.25 mm).N_(2)/CO_(2)adsorption tests were performed to evaluate the specifc surface area(SSA),pore size distribution(PSD),and pore volume(PV)using Braunuer-Emmett-Teller(BET),Barrett-Joyner-Halenda(BJH),and Density Functional Theory(DFT).The pore structure was characterized based on the theory of fractal dimensions.The results unveiled that the strength of coal has a signifcant infuence on pore structure and fractal dimensions.There are signifcant diferences in SSA and PV between both coals.The BJH-PV and BET-SSA obtained by N_(2)-adsorption for soft coal are 0.029–0.032 cm^(3)/g and 3.523–4.783 m^(2)/g.While the values of PV and SSA obtained by CO_(2)-adsorption are 0.037–0.039 cm^(3)/g and 106.016–111.870 m^(2)/g.Soft coal shows greater SSA and PV than hard coal,which is consistent with the adsorption capacity(VL).The fractal dimensions of soft and hard coal are respectively diferent.The Ding coal exhibits larger D1 and smaller D_(2),and the reverse for the Wu coal seam is observed.The greater the value of D1(complexity of pore surface)of soft coal is,the larger the pore surface roughness and gas adsorption capacity is.The results enable us to conclude that the characterization of pores and fractal dimensions of soft and hard coals is diferent,tending to diferent adsorption/desorption characteristics.In this regard,the results provide a reference for formulating corresponding coal and gas outburst prevention and control measures. 展开更多
关键词 Methane adsorption soft and hard coal Pore structure Fractal characteristics N_(2)/CO_(2)adsorption
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