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Co-enhancement of doped N and oxygen vacancies on the photocatalytic performance of ceria:Mechanism and influence of crystal faces
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作者 WANG Fan LI Jun-qi +3 位作者 MURALI Arun CHEN Chao-yi ZHANG Wei LAN Yuan-pei 《Journal of Central South University》 2025年第6期2129-2147,共19页
Nitrogen doping has significant effects on the photocatalytic performance of ceria(CeO_(2)),and the possible synergistic effect with the inevitably introduced abundant oxygen vacancies(OVs)is of great significance for... Nitrogen doping has significant effects on the photocatalytic performance of ceria(CeO_(2)),and the possible synergistic effect with the inevitably introduced abundant oxygen vacancies(OVs)is of great significance for further investigation,and the specifically exposed crystal faces of CeO_(2)may have an impact on the performance of nitrogen doped CeO_(2).Herein,nitrogen-doped CeO_(2)with different morphologies and exposed crystal faces was prepared,and its performances in the photocatalytic degradation of tetracycline(TC)or hydrogen production via water splitting were evaluated.Density functional theory(DFT)was used to simulate the band structures,density of states,and oxygen defect properties of different CeO_(2)structures.It was found that nitrogen doping and OVs synergistically promoted the catalytic activity of nitrogen-doped CeO_(2).In addition,the exposed crystal faces of CeO_(2)have significant effects on the introduction of nitrogen and the ease of OV generation,as well as the synergistic effect of nitrogen doping with OVs.Among them,the rod-like nitrogen-doped CeO_(2)with exposed(110)face(R-CeO_(2)-NH_(3))showed a photocatalytic degradation ratio of 73.59%for TC and hydrogen production of 156.89μmol/g,outperforming other prepared photocatalysts. 展开更多
关键词 nitrogen doping CeO 2 oxygen vacancies synergistic effect crystal faces PHOTOCATALYSIS
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A Comprehensive Review of Face Detection Techniques for Occluded Faces:Methods,Datasets,and Open Challenges
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作者 Thaer Thaher Majdi Mafarja +2 位作者 Muhammed Saffarini Abdul Hakim H.M.Mohamed Ayman A.El-Saleh 《Computer Modeling in Engineering & Sciences》 2025年第6期2615-2673,共59页
Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveill... Detecting faces under occlusion remains a significant challenge in computer vision due to variations caused by masks,sunglasses,and other obstructions.Addressing this issue is crucial for applications such as surveillance,biometric authentication,and human-computer interaction.This paper provides a comprehensive review of face detection techniques developed to handle occluded faces.Studies are categorized into four main approaches:feature-based,machine learning-based,deep learning-based,and hybrid methods.We analyzed state-of-the-art studies within each category,examining their methodologies,strengths,and limitations based on widely used benchmark datasets,highlighting their adaptability to partial and severe occlusions.The review also identifies key challenges,including dataset diversity,model generalization,and computational efficiency.Our findings reveal that deep learning methods dominate recent studies,benefiting from their ability to extract hierarchical features and handle complex occlusion patterns.More recently,researchers have increasingly explored Transformer-based architectures,such as Vision Transformer(ViT)and Swin Transformer,to further improve detection robustness under challenging occlusion scenarios.In addition,hybrid approaches,which aim to combine traditional andmodern techniques,are emerging as a promising direction for improving robustness.This review provides valuable insights for researchers aiming to develop more robust face detection systems and for practitioners seeking to deploy reliable solutions in real-world,occlusionprone environments.Further improvements and the proposal of broader datasets are required to developmore scalable,robust,and efficient models that can handle complex occlusions in real-world scenarios. 展开更多
关键词 Occluded face detection feature-based deep learning machine learning hybrid approaches datasets
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Functional MRI mapping of category-specific sites associated with naming of famous faces,animals and man-made objects
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作者 白红民 江涛 +3 位作者 王伟民 李天栋 刘严 卢亦成 《Neuroscience Bulletin》 SCIE CAS CSCD 2011年第5期307-318,共12页
Objective Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain ... Objective Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain controversial. The present study aimed to study the specific areas involved in naming pictures of these 3 categories using functional magnetic resonance imaging. Methods Functional images were analyzed using statistical parametric mapping and the 3 different contrasts were evaluated using t statistics by comparing the naming tasks to their baselines.The contrast images were entered into a random-effects group level analysis.The results were reported in Montreal Neurological Institute co-ordinates,and anatomical regions were identified using an automated anatomical labeling method with XJview 8.Results Naming famous faces caused more activation in the bilateral head of the hippocampus and amygdala with significant left dominance. Bilateral activation of pars triangularis and pars opercularis in the naming of famous faces was also revealed. Naming animals evoked greater responses in the left supplementary motor area, while naming man-made objects evoked more in the left premotor area,left pars orbitalis and right supplementary motor area. The extent of bilateral fusiform gyri activation by naming man-made objects was much larger than that by naming of famous faces or animals.Even in the overlapping sites of activation,some differences among the categories were found for activation in the fusiform gyri.Conclusion The cortices involved in the naming process vary with the naming of famous faces,animals and man-made objects.This finding suggests that different categories of pictures should be used during intra-operative language mapping to generate a broader map of language function, in order to minimize the incidence of false-negative stimulation and permanent post-operative deficits. 展开更多
关键词 brain mapping category-specific naming famous face animal man-made object
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基于JavaServer Faces的实验室信息管理平台 被引量:1
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作者 梁荣华 张伟 《高校实验室工作研究》 2008年第3期78-80,共3页
为实现实验室信息管理的网络化,规范实验室文档和提高实验室管理工作效率,采用JavaServer Face技术框架,设计开发了B/S体系结构实验室信息管理综合平台。通过提供丰富的人机交互用控件和后台事件处理,系统能够有效地对输入信息进行验证... 为实现实验室信息管理的网络化,规范实验室文档和提高实验室管理工作效率,采用JavaServer Face技术框架,设计开发了B/S体系结构实验室信息管理综合平台。通过提供丰富的人机交互用控件和后台事件处理,系统能够有效地对输入信息进行验证、转换。在实际运行中,证明了该平台的实用性、易用性和可扩展性。 展开更多
关键词 实验室 JAVASERVER faces 事件
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Theoretical and numerical analysis of coal dust separated by centrifugal force for working and heading faces 被引量:8
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作者 Shiqiang Chen Haiqiao Wang +3 位作者 Yiqun Li Haijiao Cui Jie Zhao Xiaowei Zhang 《International Journal of Coal Science & Technology》 EI CAS 2014年第3期338-345,共8页
In order to meet engineering needs of Chinese underground coal mines,a new dust-collecting fan,a device of dust separated by centrifugal force in driven cyclone passageway(DCCP)was designed.In centrifugal dust removal... In order to meet engineering needs of Chinese underground coal mines,a new dust-collecting fan,a device of dust separated by centrifugal force in driven cyclone passageway(DCCP)was designed.In centrifugal dust removal section(CDRS)of DCCP,a general equation is derived from the principle of force equilibrium.According to CDRS structure parameters and fan running parameters,the general equation is simplified,and the simplest equation is calculated numerically by MATLAB.The calculation results illustrate that increasing quantity of air current is against dust removal,but it is beneficial to dust removal by increasing the radius of driven spiral blade and increasing the particle diameter of coal dust.The conclusions show that the dust-collecting structure parameters coupled with the fan running parameters is a novel optimization approach to dust-collection fan for working and heading faces,which is especially suitable for Chinese underground mines. 展开更多
关键词 Working and heading faces Coal dust removal Centrifugal separation-Driven spiral passageway
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Seismic reliability analysis of shield tunnel faces under multiple failure modes by pseudo-dynamic method and response surface method 被引量:7
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作者 ZHANG Jia-hua XU Peng +1 位作者 SUN Wang-cheng LI Bo 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1553-1564,共12页
In order to investigate the stability problem of shield tunnel faces subjected to seismic loading,the pseudodynamic method(P-DM)was employed to analyze the seismic effect on the face.Two kinds of failure mechanisms of... In order to investigate the stability problem of shield tunnel faces subjected to seismic loading,the pseudodynamic method(P-DM)was employed to analyze the seismic effect on the face.Two kinds of failure mechanisms of active collapse and passive extrusion were considered,and a seismic reliability model of shield tunnel faces under multifailure mode was established.The limit analysis method and the response surface method(RSM)were used together to solve the reliability of shield tunnel faces subjected to seismic action.Comparing with existing results,the results of this work are effective.The effects of seismic load and rock mass strength on the collapse pressure,extrusion pressure and reliability index were discussed,and reasonable ranges of support pressure of shield tunnel faces under seismic action were presented.This method can provide a new idea for solving the shield thrust parameter under the seismic loading. 展开更多
关键词 shield tunnel face pseudo-dynamic method seismic effect multi-failure mode support pressure range
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The early development of face processing——What makes faces special? 被引量:4
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作者 Stefanie Hoehl Stefanie Peykarjou 《Neuroscience Bulletin》 SCIE CAS CSCD 2012年第6期765-788,共24页
In the present article we review behavioral and neurophysiological studies on face processing in adults and in early development. From the existing empirical and theoretical literature we derive three aspects that dis... In the present article we review behavioral and neurophysiological studies on face processing in adults and in early development. From the existing empirical and theoretical literature we derive three aspects that distinguish face processing from the processing of other visual object categories. Each of these aspects is discussed from a developmental perspective. First, faces are recognized and represented at the individual level rather than at the basic level. Second, humans typically acquire extensive expertise in individuating faces from early on in development. And third, more than other objects, faces are processed holistically. There is a quantitative difference in the amount of visual experience for faces and other object categories in that the amount of expertise typically acquired for faces is greater than that for other object categories. In addition, we discuss possible qualitative differences in experience for faces and objects. For instance, there is evidence for a sensitive period in infancy for building up a holistic face representation and for perceptual narrowing for faces of one's own species and race. We conclude our literature review with questions for future research, for instance, regarding the exact relationship between behavioral and neuronal markers of face processing across development. 展开更多
关键词 face processing development INFANTS visual expertise holistic processing event-related potential
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Interaction Between Conscious and Unconscious Information-Processing of Faces and Words 被引量:3
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作者 Shiwen Ren Hanyu Shao Sheng He 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第11期1583-1594,共12页
It is widely acknowledged that holistic processing is a key characteristic of face perception.Although holistic processing implies the automatic integration of face parts,it is unclear whether such processing requires... It is widely acknowledged that holistic processing is a key characteristic of face perception.Although holistic processing implies the automatic integration of face parts,it is unclear whether such processing requires the awareness of face parts.Here,we investigated the interactions between visible face parts and face parts rendered invisible using continuous flash suppression(CFS).In the first experiment with the upper half-face visible and the lower half-face invisible,the results showed that perceived face identity was influenced by the invisible lower half-face,suggesting that integration occurs between the visible and invisible face parts,a variant of the“composite face effect”.In the second experiment,we investigated the influence of visible face parts on the processing of invisible face parts,as measured by the time it took for the invisible parts to break out from CFS.The results showed a visible-to-invisible facilitation effect,that the aligned invisible face parts broke through CFS faster than when the visible and invisible face parts were misaligned.Visible eyes had a stronger influence on the invisible nose/mouth than the other way around.Such facilitation of processing from visible to invisible parts was also found when Chinese characters were used as stimuli.These results show that information integration occurs across the consciousness boundary. 展开更多
关键词 Holistic processing Face Word AWARENESS Integration across conscious boundary
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Patterns governing distribution of surrounding-rock stress and strata behaviors of fully-mechanized caving faces 被引量:3
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作者 谢广祥 刘全明 +1 位作者 查文华 华心祝 《Journal of Coal Science & Engineering(China)》 2004年第1期5-8,共4页
By employing numerical modeling, similar material simulation and comprehen-sive field observation, investigations were made and patterns were obtained governing surrounding-rock stress distribution and strata behavior... By employing numerical modeling, similar material simulation and comprehen-sive field observation, investigations were made and patterns were obtained governing surrounding-rock stress distribution and strata behaviors. It shows that patterns governing displacement of FMC roadway surrounding rocks and those governing deformation of supports are basically the same along the strike, but the displacements vary greatly. The front stresses affect greater areas than the lateral stresses and their limit widths of equilib-rium zones and K are almost similar. The stress transmits very deep. Our findings offer scientific basis on which to determine parameters for coal pillar retaining and for roadway out-laying, thus increasing the recovery ratio and improving the maintenance of roadway. 展开更多
关键词 fully-mechanized caving face (FMC faces) stress surrounding-rock stress
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Investigation on the stress field characteristic of top coal at FMTC faces under the influence of caving thickness 被引量:5
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作者 谢广祥 常聚才 杨科 《Journal of Coal Science & Engineering(China)》 2007年第2期123-125,共3页
In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress red... In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress redistribution rules of top coal with different thick coal seam were obtained by investigation on the numerical simulation of the redistributions of the stress with different coal seam's thickness. The research showes that there exists a certain difference on the stress distributions of the top coal at face, the maximum principal stress is located near to the tailentry's corner. The vertical stress's peak of the top coal decreases and the distance ahead of face position increases as the once mining thickness of the coal seam increases. At the same coal seam, the vertical stresses' peak of top coal gradually decreases from the top to the bottom, the peak's position is basically the same and its changes are gradually obvious with the thickness of coal seam increas- ing. The vertical stress of top coal places in a low stress state at a certain range ahead of face and over the face, which reveals the essence that the support loads are generally low under the condition of FMTC. The study supplies the theoretical foundation for the support design and selection, the theory of top coal's fragmentation, the movement rules of top coal and improving the recovery of top coal. 展开更多
关键词 fully mechanized top-coal caving face thickness of coal seam top coal stress field
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Experiment on Wear Behavior of High Pressure Gas Seal Faces 被引量:2
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作者 XU Jing PENG Xudong +2 位作者 BAI Shaoxian MENG Xiangkai LI Jiyun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1287-1293,共7页
Current researches show that mechanical deformation of seal ring face makes fluid film clearance decrease at high pressure side, thus a divergent clearance is formed and face wear occurs more seriously at the high pre... Current researches show that mechanical deformation of seal ring face makes fluid film clearance decrease at high pressure side, thus a divergent clearance is formed and face wear occurs more seriously at the high pressure side than that on the low pressure side. However, there is still lack of published experimental works enough to prove the theoretical results. In this paper, a spiral groove dry gas seal at high pressures is experimentally investigated so as to prove the face wear happened at the high pressure side of seal faces due to the face mechanical deformation, and the wear behavior affected by seal ring structure is also studied. The experimental results show that face wear would occur at the high pressure side of seal faces due to the deformation, thus the leakage and face temperature increase, which all satisfies the theoretical predictions. When sealed pressure is not less than 5 MPa, the pressure can provide enough opening force to separate the seal faces. The seal ring sizes have obvious influence on face wear. Face wear, leakage and face temperature of a dry gas seal with the smaller cross sectional area of seal ring are less than that of a dry gas seal with bigger one, and the difference of leakage rate between these two sizes of seal face width is in the range of 24%–25%. Compared with the effect of seal ring sizes, the effect of secondary O-ring seal position on face deformation and face wear is less. The differences between these two types of dry gas seals with different secondary O-ring seal positions are less than 5.9% when the rotational speed varies from 0 to 600 r/min. By linking face wear and sealing performance changes to the shift in mechanical deformation of seal ring, this research presents an important experimental method to study face deformation of a dry gas seal at high pressures. 展开更多
关键词 dry gas seal STRUCTURES face wear high pressure mechanical deformation
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Two faces of Schwann cell dedifferentiation in peripheral neurodegenerative diseases:pro-demyelinating and axon-preservative functions 被引量:3
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作者 Jong Kuk Kim Hye Jeong Lee Hwan Tae Park 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第22期1952-1954,共3页
Schwann cells are glial cells that are responsible for the synthesis and maintenance of the myelin sheath in the peripheral nerve system. Under pathological conditions, such as physical nerve injury and inflammatory n... Schwann cells are glial cells that are responsible for the synthesis and maintenance of the myelin sheath in the peripheral nerve system. Under pathological conditions, such as physical nerve injury and inflammatory neuropathies, Schwann cells undergo a substantial phenotype transformation that is not related to their intended function. For example, Schwann cells dedifferentiate into immature states and thereby cease to express myelin genes after nerve injury. 展开更多
关键词 cell Two faces of Schwann cell dedifferentiation in peripheral neurodegenerative diseases
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A Novel Face Recognition Algorithm for Distinguishing Faces with Various Angles 被引量:3
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作者 Yong-Zhong Lu 《International Journal of Automation and computing》 EI 2008年第2期193-197,共5页
In order to distinguish faces of various angles during face recognition, an algorithm of the combination of approximate dynamic programming (ADP) called action dependent heuristic dynamic programming (ADHDP) and p... In order to distinguish faces of various angles during face recognition, an algorithm of the combination of approximate dynamic programming (ADP) called action dependent heuristic dynamic programming (ADHDP) and particle swarm optimization (PSO) is presented. ADP is used for dynamically changing the values of the PSO parameters. During the process of face recognition, the discrete cosine transformation (DCT) is first introduced to reduce negative effects. Then, Karhunen-Loeve (K-L) transformation can be used to compress images and decrease data dimensions. According to principal component analysis (PCA), the main parts of vectors are extracted for data representation. Finally, radial basis function (RBF) neural network is trained to recognize various faces. The training of RBF neural network is exploited by ADP-PSO. In terms of ORL Face Database, the experimental result gives a clear view of its accurate efficiency. 展开更多
关键词 Face recognition approximate dynamic programming (ADP) particle swarm optimization (PSO)
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Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network 被引量:1
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作者 Hongwei Huang Chen Wu +3 位作者 Mingliang Zhou Jiayao Chen Tianze Han Le Zhang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期323-337,共15页
Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantita... Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative parameters.However,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality prediction.In this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak interlayers.The site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is established.Considering the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete dataset.By utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality. 展开更多
关键词 Rock mass quality Tunnel faces Incomplete multi-source dataset Improved Swin Transformer Bayesian networks
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Determining the rational layout parameters of the lateral high drainage roadway serving for two adjacent working faces 被引量:2
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作者 Li Shugang Shuang Haiqing Wang Hongsheng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期795-801,共7页
To determine the rational layout parameters of the lateral high drainage roadway(LHDR) serving for two adjacent working faces, a mechanical model of the LHDR under mining influence was established, and the overburden ... To determine the rational layout parameters of the lateral high drainage roadway(LHDR) serving for two adjacent working faces, a mechanical model of the LHDR under mining influence was established, and the overburden fissure, mining-induced stress distribution rules were analyzed. First, the development characteristics of mining-induced overburden fissure and the stress distribution law of the upper section of the working face were analyzed. Second, by analyzing the distribution law of vertical stress at different layers, the lateral distance of the LHDR was determined as 25 m. Third, by analyzing the surrounding rock deformation effect, stress distribution law, and overburden fissure distribution law of the LHDR at the heights of 20, 25, and 30 m away from the roof, the rational horizon of the LHDR was determined to be 25 m. Finally, an example of a LHDR located 25 m above the roof of the No. 2 coal seam and 25 m away from the No. 2-603 working face was presented. Results show that when the No. 2-603 coalface is being mined, the surrounding rocks lag 80 m or even further and the working face tends to be stable. The relative deformations of the roof and floor of the roadway and both of its walls were 583 and 450 mm,respectively. The reduction rate of the roadway section was 21.52%–25.32%. The section of the roadway was sufficient to extract the pressure relief gas in the overburden of the No. 2-605 working face. The average gas concentration and the pure volume at the branch pipeline were 24.8% and 22.3 m^3/min,respectively, showing that the position of high-level boreholes was reasonable. 展开更多
关键词 Lateral high drainage roadway(LHDR) One gateway with two utilizations Working face overburden Pressure relief gas Surrounding rock’s stability
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Mathematical Model and Machining Method for Spiral Flute Rake Faces of Hourglass Worm Gear Hob 被引量:1
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作者 YANG Jie LI Haitao +2 位作者 RUI Chengjie HUANG Yi ZHANG Xiaodi 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第3期401-412,共12页
To improve the cutting performance of an hourglass worm gear hob and the accuracy of the resulting worm gear,the rake angles of the teeth on the pitch circle should be reduced.A method of forming the spiral flutes by ... To improve the cutting performance of an hourglass worm gear hob and the accuracy of the resulting worm gear,the rake angles of the teeth on the pitch circle should be reduced.A method of forming the spiral flutes by using a variable transmission ratio was developed.This method ensures that the rake angles on the indexing torus of each tooth are approximately 0°.Based on the gear meshing theory and the hourglass worm forming method,the discretization mathematical model of the rake face of a planar double enveloping worm gear hob was established by using cylindrical generating surface,and the feed parameters for machining the rake face for a variable transmission ratio were obtained.The spiral flute was simulated and the hob was machined on a four axis CNC milling machine.A contourgraph was used to measure the rake angle.The measurement results showed that the proposed method can reduce the absolute value of the rake angle on both sides of the cutting teeth,which can be used for machining the spiral flute rake face of an hourglass worm gear hob. 展开更多
关键词 HOURGLASS WORM gear HOB cylindrical generating surface SPIRAL FLUTE RAKE face RAKE angle
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Putting Faces to Names: Snapshots of Two Committee Meetings, 95 Years Apart, Emphasize Continuous International Cooperation in the Atmospheric Sciences 被引量:1
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作者 Hans VOLKERT 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第5期571-575,共5页
1.Introduction Spectacular advances have been made in the atmospheric sciences on a global level during a period of one hundred years or more,which is arguably most evident through"the quiet revolution of numeric... 1.Introduction Spectacular advances have been made in the atmospheric sciences on a global level during a period of one hundred years or more,which is arguably most evident through"the quiet revolution of numerical weather prediction"(Bauer et 展开更多
关键词 Co work Putting faces to Names:Snapshots of Two Committee Meetings 95 Years Apart Emphasize Continuous International Cooperation in the Atmospheric Sciences
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Influence of mining thickness to the mechanical characteristics of gateways at FMTC faces 被引量:1
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作者 谢广祥 王磊 《Journal of Coal Science & Engineering(China)》 2008年第1期1-5,共5页
To make a better understanding of the mechanical characteristics of the surrounding rocks in the tailentry and headentry with different coal seam thickness at fully mechanized top-coal caving face (FMTC face), the s... To make a better understanding of the mechanical characteristics of the surrounding rocks in the tailentry and headentry with different coal seam thickness at fully mechanized top-coal caving face (FMTC face), the stress transition and displacement around the periphery of the gateways with different coal thicknesses were investigated in details by means of in situ measurement and 3-D numerical simulation. The research shows that the stresses decrease in the two spallings of the headentry and floor at goal with the increase in mining thickness. The roof pressure in the gates does not change obviously with the coal thickness, but the thicker the coal seam is, the farther the maximum stress will apply to the coal rib at the working face. The vertical stress is higher than the horizontal stress at two spallings of the gate, while its horizontal stress is higher than the vertical stress at the roof. The relative displacement between the roof and floor and the two spallings in the gateways increases gradually with the increase in coal seam thickness in a definite range in front of the face. Near the mining face, the stress decreases in the surrounding rock of the gates, while the deformation appears the most intensive. It is proposed that the support concept to the tailentry and headentry should be changed from loading control to deformation control. 展开更多
关键词 FMTC face coal seam thickness GATEWAYS STRESS DISPLACEMENT
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Development of Trusted Network and Challenges It Faces 被引量:3
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作者 Lin Chuang 1, Wang Yuanzhuo 1, Tian Liqin 1,2 (1. Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China 2. Department of Computer, North China Institute of Science and Technology, Beijing 101601, China) 《ZTE Communications》 2008年第1期13-17,共5页
As the information network plays a more and more important role globally, the traditional network theories and technologies, especially those related to network security, can no longer meet the network development req... As the information network plays a more and more important role globally, the traditional network theories and technologies, especially those related to network security, can no longer meet the network development requirements. Offering the system with secure and trusted services has become a new focus in network research. This paper first discusses the meaning of and aspects involved in the trusted network. According to this paper, the trusted network should be a network where the network’s and users’ behaviors and their results are always predicted and manageable. The trustworthiness of a network mainly involves three aspects: service provider, information transmission and terminal user. This paper also analyzes the trusted network in terms of trusted model for network/user behaviors, architecture of trusted network, service survivability and network manageability, which is designed to give ideas on solving the problems that may be faced in developing the trusted network. 展开更多
关键词 Development of Trusted Network and Challenges It faces
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Periocular Biometric Recognition for Masked Faces 被引量:1
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作者 HUANG Qiaoyue TANG Chaoying ZHANG Tianshu 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第2期141-149,共9页
Since the outbreak of Coronavirus Disease 2019(COVID-19),people are recommended to wear facial masks to limit the spread of the virus.Under the circumstances,traditional face recognition technologies cannot achieve sa... Since the outbreak of Coronavirus Disease 2019(COVID-19),people are recommended to wear facial masks to limit the spread of the virus.Under the circumstances,traditional face recognition technologies cannot achieve satisfactory results.In this paper,we propose a face recognition algorithm that combines the traditional features and deep features of masked faces.For traditional features,we extract Local Binary Pattern(LBP),Scale-Invariant Feature Transform(SIFT)and Histogram of Oriented Gradient(HOG)features from the periocular region,and use the Support Vector Machines(SVM)classifier to perform personal identification.We also propose an improved Convolutional Neural Network(CNN)model Angular Visual Geometry Group Network(A-VGG)to learn deep features.Then we use the decision-level fusion to combine the four features.Comprehensive experiments were carried out on databases of real masked faces and simulated masked faces,including frontal and side faces taken at different angles.Images with motion blur were also tested to evaluate the robustness of the algorithm.Besides,the experiment of matching a masked face with the corresponding full face is accomplished.The experimental results show that the proposed algorithm has state-of-the-art performance in masked face recognition,and the periocular region has rich biological features and high discrimination. 展开更多
关键词 masked face recognition periocular Visual Geometry Group(VGG) Local Binary Pattern(LBP) Scale-Invariant Feature Transform(SIFT) Histogram of Oriented Gradient(HOG) Support Vector Machines(SVM)
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