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预测儿童Ⅱ期人工晶状体植入术后青光眼相关不良事件的风险:一项为期3年的研究
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作者 Hui Chen Chaoqun Xu +13 位作者 Ling Jin zhenyu wang Jingmin Xu Yingshi Zou Guangming Jin Lixia Luo Haotian Lin Weirong Chen Danying Zheng Yizhi Liu Zhenzhen Liu 金佳昕(审校) 陈子东(审校) 《眼科学报》 CAS 2024年第5期234-245,共12页
目的:建立并评估儿童Ⅱ期人工晶状体(intraocular lens,IOL)植入术后青光眼相关不良事件(glaucomarelated adverse events,GRAEs)的预测模型。方法:选取于中山大学中山眼科中心行Ⅱ期IOL植入术的无晶状体眼患儿205例(356眼),并在术后对... 目的:建立并评估儿童Ⅱ期人工晶状体(intraocular lens,IOL)植入术后青光眼相关不良事件(glaucomarelated adverse events,GRAEs)的预测模型。方法:选取于中山大学中山眼科中心行Ⅱ期IOL植入术的无晶状体眼患儿205例(356眼),并在术后对其随访3年。采用Cox比例风险模型确定GRAEs的预测因子,并建立列线图预测模型。采用随时间变化的受试者工作特征(receiver operating characteristic,ROC)曲线、决策曲线分析、Kaplan-Meier曲线评估模型性能,并通过Bootstrapping的C指数和校准图进行内部验证。结果:行Ⅱ期IOL植入术时年龄较大(HR=1.50,95%CI:1.03~2.19)、术后一过性高眼压(HR=9.06,95%CI:2.97~27.67)和IOL睫状沟植入术(HR=14.55,95%CI:2.11~100.57)是GRAEs的危险因素(均P<0.05),并据此建立了两个列线图预测模型。在术后1、2、3年,模型1的ROC曲线下面积(area under curve,AUC)分别为0.747(95%CI:0.776~0.935)、0.765(95%CI:0.804~0.936)和0.748(95%CI:0.736~0.918),模型2的AUC分别为0.881(95%CI:0.836~0.926)、0.895(95%CI:0.852~0.938)和0.848(95%CI:0.752~0.945)。在内部验证和评价中,两种模型均表现出良好的性能和临床净效益。Kaplan-Meier曲线显示两个不同的风险组在两个模型中都能被显著且稳健地区分。此外,本研究也构建了在线风险计算器。结论:两种列线图均能灵敏、准确地识别Ⅱ期IOL植入术后GRAEs的高危患儿,有助对其进行早期识别和及时干预。 展开更多
关键词 儿童健康(儿科) 青光眼 晶状体和悬韧带 视力
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Skyrmion motion induced by spin-waves on magnetic nanotubes
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作者 Tijjani Abdulrazak Xuejuan Liu +2 位作者 zhenyu wang Yunshan Cao Peng Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期413-418,共6页
We investigate the skyrmion motion driven by spin waves on magnetic nanotubes through micromagnetic simulations.Our key results include demonstrating the stability and enhanced mobility of skyrmions on the edgeless na... We investigate the skyrmion motion driven by spin waves on magnetic nanotubes through micromagnetic simulations.Our key results include demonstrating the stability and enhanced mobility of skyrmions on the edgeless nanotube geometry,which prevents destruction at boundaries—a common issue in planar geometries.We explore the influence of the damping coefficient,amplitude,and frequency of microwaves on skyrmion dynamics,revealing a non-uniform velocity profile characterized by acceleration and deceleration phases.Our results show that the skyrmion Hall effect is significantly modulated on nanotubes compared to planar models,with specific dependencies on the spin-wave parameters.These findings provide insights into skyrmion manipulation for spintronic applications,highlighting the potential for high-speed and efficient information transport in magnonic devices. 展开更多
关键词 FERROMAGNETIC magnetic nanotube Mumax3 software SKYRMION SPIN-WAVE
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Efficient concentration of trace analyte with ordered hotspot construction for a robust and sensitive SERS platform
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作者 Youdi Hu Yanlei Hu +4 位作者 zhenyu wang Jiale Yong Wei Xiong Dong Wu Shixiang Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期532-542,共11页
Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions c... Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive detection.However,subject to the difficulty of the fabrication process,itremains challenging to balance hot-spot construction and the concentration capacity of analyte simultaneously.Therefore,preparing SERS substrates with densely ordered hot spots andefficient concentration capacity is of great significance for highly sensitive detection.Herein,we propose an Ag and fluoroalkyl-modified hierarchical armour substrate(Ag/F-HA),which has a double-layer stacking design to combine analyte concentration with hotspot construction.The microarmour structure is fabricated by femtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surface to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot spots.Under the synergistic action of hot spots and analyte concentration,Ag/F-HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of 7.69%.Additionally,Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or abrasion.Based on our strategy,SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with defects.This work opens a way to the realistic implementation of SERS in diverse scenarios. 展开更多
关键词 surface-enhanced Raman scattering anodic aluminium oxide femtosecond laser processing concentration of trace analytes mechanical robustness
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Fake News Detection Based on Cross-Modal Message Aggregation and Gated Fusion Network
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作者 Fangfang Shan Mengyao Liu +1 位作者 Menghan Zhang zhenyu wang 《Computers, Materials & Continua》 SCIE EI 2024年第7期1521-1542,共22页
Social media has become increasingly significant in modern society,but it has also turned into a breeding ground for the propagation of misleading information,potentially causing a detrimental impact on public opinion... Social media has become increasingly significant in modern society,but it has also turned into a breeding ground for the propagation of misleading information,potentially causing a detrimental impact on public opinion and daily life.Compared to pure text content,multmodal content significantly increases the visibility and share ability of posts.This has made the search for efficient modality representations and cross-modal information interaction methods a key focus in the field of multimodal fake news detection.To effectively address the critical challenge of accurately detecting fake news on social media,this paper proposes a fake news detection model based on crossmodal message aggregation and a gated fusion network(MAGF).MAGF first uses BERT to extract cumulative textual feature representations and word-level features,applies Faster Region-based ConvolutionalNeuralNetwork(Faster R-CNN)to obtain image objects,and leverages ResNet-50 and Visual Geometry Group-19(VGG-19)to obtain image region features and global features.The image region features and word-level text features are then projected into a low-dimensional space to calculate a text-image affinity matrix for cross-modal message aggregation.The gated fusion network combines text and image region features to obtain adaptively aggregated features.The interaction matrix is derived through an attention mechanism and further integrated with global image features using a co-attention mechanism to producemultimodal representations.Finally,these fused features are fed into a classifier for news categorization.Experiments were conducted on two public datasets,Twitter and Weibo.Results show that the proposed model achieves accuracy rates of 91.8%and 88.7%on the two datasets,respectively,significantly outperforming traditional unimodal and existing multimodal models. 展开更多
关键词 Fake news detection cross-modalmessage aggregation gate fusion network co-attention mechanism multi-modal representation
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Deep Learning Social Network Access Control Model Based on User Preferences
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作者 Fangfang Shan Fuyang Li +3 位作者 zhenyu wang Peiyu Ji Mengyi wang Huifang Sun 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1029-1044,共16页
A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social networks.Firstly,socialusers andsocialdata entities are extractedfromthe social netw... A deep learning access controlmodel based on user preferences is proposed to address the issue of personal privacy leakage in social networks.Firstly,socialusers andsocialdata entities are extractedfromthe social networkandused to construct homogeneous and heterogeneous graphs.Secondly,a graph neural networkmodel is designed based on user daily social behavior and daily social data to simulate the dissemination and changes of user social preferences and user personal preferences in the social network.Then,high-order neighbor nodes,hidden neighbor nodes,displayed neighbor nodes,and social data nodes are used to update user nodes to expand the depth and breadth of user preferences.Finally,a multi-layer attention network is used to classify user nodes in the homogeneous graph into two classes:allow access and deny access.The fine-grained access control problem in social networks is transformed into a node classification problem in a graph neural network.The model is validated using a dataset and compared with other methods without losing generality.The model improved accuracy by 2.18%compared to the baseline method GraphSAGE,and improved F1 score by 1.45%compared to the baseline method,verifying the effectiveness of the model. 展开更多
关键词 Graph neural networks user preferences access control social network
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Automatic Generation of Attribute-Based Access Control Policies from Natural Language Documents
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作者 Fangfang Shan zhenyu wang +1 位作者 Mengyao Liu Menghan Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第9期3881-3902,共22页
In response to the challenges of generating Attribute-Based Access Control(ABAC)policies,this paper proposes a deep learning-based method to automatically generate ABAC policies from natural language documents.This me... In response to the challenges of generating Attribute-Based Access Control(ABAC)policies,this paper proposes a deep learning-based method to automatically generate ABAC policies from natural language documents.This method is aimed at organizations such as companies and schools that are transitioning from traditional access control models to the ABAC model.The manual retrieval and analysis involved in this transition are inefficient,prone to errors,and costly.Most organizations have high-level specifications defined for security policies that include a set of access control policies,which often exist in the form of natural language documents.Utilizing this rich source of information,our method effectively identifies and extracts the necessary attributes and rules for access control from natural language documents,thereby constructing and optimizing access control policies.This work transforms the problem of policy automation generation into two tasks:extraction of access control statements andmining of access control attributes.First,the Chat General Language Model(ChatGLM)isemployed to extract access control-related statements from a wide range of natural language documents by constructing unique prompts and leveraging the model’s In-Context Learning to contextualize the statements.Then,the Iterated Dilated-Convolutions-Conditional Random Field(ID-CNN-CRF)model is used to annotate access control attributes within these extracted statements,including subject attributes,object attributes,and action attributes,thus reassembling new access control policies.Experimental results show that our method,compared to baseline methods,achieved the highest F1 score of 0.961,confirming the model’s effectiveness and accuracy. 展开更多
关键词 Access control policy generation natural language deep learning
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Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae
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作者 zhenyu wang Jujia Zhang +1 位作者 Xinzhong Er Jinming Bai 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期183-191,共9页
The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients accurately.This telescope system can be crucial in ... The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients accurately.This telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to start.By considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by Mephisto.The best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 days.In this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.Given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia. 展开更多
关键词 (stars:)supernovae:general (cosmology:)cosmological parameters telescopes
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3D Printed Integrated Gradient-Conductive MXene/CNT/Polyimide Aerogel Frames for Electromagnetic Interference Shielding with Ultra-Low Reflection 被引量:18
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作者 Tiantian Xue Yi Yang +5 位作者 Dingyi Yu Qamar Wali zhenyu wang Xuesong Cao Wei Fan Tianxi Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期332-345,共14页
Construction of advanced electromagnetic interference(EMI)shielding materials with miniaturized,programmable structure and low reflection are promising but challenging.Herein,an integrated transition-metal carbides/ca... Construction of advanced electromagnetic interference(EMI)shielding materials with miniaturized,programmable structure and low reflection are promising but challenging.Herein,an integrated transition-metal carbides/carbon nanotube/polyimide(gradient-conductive MXene/CNT/PI,GCMCP)aerogel frame with hierarchical porous structure and gradient-conductivity has been constructed to achieve EMI shielding with ultra-low reflection.The gradient-conductive structures are obtained by continuous 3D printing of MXene/CNT/poly(amic acid)inks with different CNT contents,where the slightly conductive top layer serves as EM absorption layer and the highly conductive bottom layer as reflection layer.In addition,the hierarchical porous structure could extend the EM dissipation path and dissipate EM by multiple reflections.Consequently,the GCMCP aerogel frames exhibit an excellent average EMI shielding efficiency(68.2 dB)and low reflection(R=0.23).Furthermore,the GCMCP aerogel frames with miniaturized and programmable structures can be used as EMI shielding gaskets and effectively block wireless power transmission,which shows a prosperous application prospect in defense industry and aerospace. 展开更多
关键词 3D printing MXene/CNT/Polyimide aerogel Gradient-conductive Electromagnetic interference shielding
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High-Entropy Alloys to Activate the Sulfur Cathode for Lithium-Sulfur Batteries 被引量:3
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作者 zhenyu wang Hailun Ge +2 位作者 Sheng Liu Guoran Li Xueping Gao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期40-49,共10页
Sulfur element possesses an ultrahigh theoretical specific capacity,while the utilization of sulfur in the whole cathode is lower obviously owing to the sluggish kinetics of sulfur and discharged products,limiting the... Sulfur element possesses an ultrahigh theoretical specific capacity,while the utilization of sulfur in the whole cathode is lower obviously owing to the sluggish kinetics of sulfur and discharged products,limiting the enhancement on energy density of lithium-sulfur batteries.Herein,for the first time,Fe_(0.24)Co_(0.26)Ni_(0.10)Cu_(0.15)Mn_(0.25)high-entropy alloy is introduced as the core catalytic host to activate the electrochemical performance of the sulfur cathode for lithium-sulfur batteries.It is manifested that Fe_(0.24)Co_(0.26)Ni_(0.10)Cu_(0.15)Mn_(0.25)high-entropy alloy nanocrystallites distributed on nitrogen-doped carbon exhibit high electrocatalytic activity toward the conversion of solid sulfur to solid discharged products across soluble intermediate lithium polysulfides.In particular,benefiting from the accelerated kinetics by high-entropy alloy nanocrystallites and synergistic adsorption by nitrogen-doped carbon,the cathode exhibits high reversible capacity of 1079.5 mAh g_(-cathode)^(-1)(high utilization of 89.4%)with the whole cathode as active material,instead of sulfur element.Moreover,under both lean electrolyte(3μmg^(-1))and ultrahigh sulfur loading(27.0 mg cm^(-2))condition,the high discharge capacity of 868.2 mAh g_(-cathode)^(-1)can be still achieved for the sulfur cathode.This strategy opens up a new path to explore catalytic host materials for enhancing the utilization of sulfur in the whole cathode for lithium-sulfur batteries. 展开更多
关键词 catalytic host electrochemical performance high-entropy alloy lithium–sulfur batteries sulfur cathode
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CO_(2)和N_(2)电还原中缺陷及界面工程的最新进展 被引量:2
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作者 陈瑶 陈存 +3 位作者 曹雪松 王震宇 张楠 刘天西 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第8期56-70,共15页
实现碳氮循环是人类社会发展的迫切要求,也是催化领域的热门研究课题。在可再生能源的推动下,电催化技术引起了人们的广泛关注,且可以通过改变反应电压获得不同的目标产品。基于此,电催化技术被认为是缓解当前能源危机和环境问题的有效... 实现碳氮循环是人类社会发展的迫切要求,也是催化领域的热门研究课题。在可再生能源的推动下,电催化技术引起了人们的广泛关注,且可以通过改变反应电压获得不同的目标产品。基于此,电催化技术被认为是缓解当前能源危机和环境问题的有效策略,对实现碳中和具有重要意义。其中,电催化CO_(2)还原反应(CO_(2)RR)和N_(2)还原反应(N_(2)RR)是一种有前途的小分子转化策略。然而,CO_(2)和N_(2)均为线性分子,其中C=O和N≡N键的高解离能导致了它们高的化学惰性。此外,最高占据分子轨道(HOMO)和最低未占分子轨道(LUMO)之间的巨大能量间隙使它们具有高的化学稳定性;且CO_(2)和N_(2)的低质子亲和力使它们难以被直接质子化。另一方面,由于CO_(2)RR和N_(2)RR与析氢反应(HER)具有相近的氧化还原电位,造成其与HER之间存在竞争性关系,这也是致使催化剂在CO_(2)RR和N_(2)RR转化效率低的重要影响因素。因此,CO_(2)RR和N_(2)RR仍然面临着过电位高及法拉第效率低等问题。为了克服这些瓶颈,人们为提升CO_(2)RR和N_(2)RR电催化剂性能做出了很多努力。众所周知,电催化过程发生在催化剂表面,主要涉及质量传递和电子转移等过程。由此可见,催化剂的性能与其质量和电子传输能力密切相关,而调控催化剂表面结构可以优化活性点的质量和电子转移行为。电催化剂的缺陷和界面工程可通过表面原子工程来实现电子结构调控,对于提高气体吸附能力、抑制HER、富集气体及稳定中间产物等具有重要意义。到目前为止,所报道的各种缺陷和复合电催化剂在提高CO_(2)RR和N_(2)RR催化性能等方面均表现出巨大的潜力。在此,我们综述了CO_(2)RR和N_(2)RR中催化剂缺陷工程及界面工程的最新进展;首先讨论了四种不同的缺陷(空位、高指数晶面、晶格应变和晶格无序)对CO_(2)RR和N_(2)RR性能的影响;然后,总结了界面工程在聚合物-无机复合材料催化剂中的重要作用,并给出了典型实例;最后,展望了原子级电催化剂工程的发展前景,提出了开发和设计高效CO_(2)RR和N_(2)RR电催化剂的未来发展方向。 展开更多
关键词 缺陷 界面 纳米复合材料 二氧化碳还原反应 氮气还原反应
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Synergy of I-Cl co-occupation on halogen-rich argyrodites and resultant dual-layer interface for advanced all-solid-state Li metal batteries
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作者 Han Yan Ruifeng Song +6 位作者 Ruonan Xu Shulin Li Qiaoquan Lin Xinlin Yan zhenyu wang Chuang Yu Long Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期499-509,I0011,共12页
The(electro)chemical stability and Li dendrite suppression capability of sulfide solid electrolytes(SEs)need further improvement for developing all-solid-state Li batteries(ASSLBs).Here,we report advanced halogen-rich... The(electro)chemical stability and Li dendrite suppression capability of sulfide solid electrolytes(SEs)need further improvement for developing all-solid-state Li batteries(ASSLBs).Here,we report advanced halogen-rich argyrodites via I and Cl co-occupation on the crystal lattice.Notably,a proper I content forms a single phase,whereas an excessive I causes precipitation of two argyrodite phases like a superlattice structure.The resultant synergistic effect of the optimized composition allows to gain high ionic conductivities at room temperature and-20℃,and enhances the(electro)chemical stability against Li and Li dendrite suppression capability.The Li|argyrodite interface is very sensitive to the ratio of I and Cl.A LiCl-and LiI-rich double-layer interface is observed from the cell using the SE with optimized composition,whereas too high I content forms only a single interface layer with a mixture of Lil and LiCl.This double-layer interface is found to effectively mitigate the Li/SE reaction.The proper designed argyrodite enables ASSLBs to achieve good electrochemical properties at a broad temperature range regardless of the electrode materials.This co-occupation strategy provides a novel exploration for advanced halogen-rich argyrodite system. 展开更多
关键词 Sulfide solid electrolytes Argyrodites Dual doping Li metal anode Solid-state batteries
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Numerical Simulation Analysis of the Transformer Fire Extinguishing Process with a High-Pressure Water Mist System under Different Conditions
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作者 Haowei Yao Youxin Li +7 位作者 Kefeng Lv Dong wang Jinguang Zhang zhenyu Zhan zhenyu wang Huaitao Song Xiaoge Wei Hengjie Qin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期733-747,共15页
To thoroughly study the extinguishing effect of a high-pressure water mist fire extinguishing system when a transformer fire occurs,a 3D experimental model of a transformer is established in this work by employing Fir... To thoroughly study the extinguishing effect of a high-pressure water mist fire extinguishing system when a transformer fire occurs,a 3D experimental model of a transformer is established in this work by employing Fire Dynamics Simulator(FDS)software.More specifically,by setting different parameters,the process of the highpressure water mist fire extinguishing system with the presence of both diverse ambient temperatures and water mist sprinkler laying conditions is simulated.In addition,the fire extinguishing effect of the employed high-pressure water mist system with the implementation of different strategies is systematically analyzed.The extracted results show that a fire source farther away fromthe centerline leads to a lower local temperature distribution.In addition,as the ambient temperature increases,the temperature above the fire source decreases,while the temperature and the concentrationof theupperflue gas layer bothdecrease.Interestingly,after thehigh-pressurewatermist sprinkler begins to operate,both the temperature distribution above the fire source and the concentration of the flue gas decrease,which indicates that the high-pressure water mist system plays the role of cooling and dust removal.By comparing various sprinkler laying methods,it is found that the lower sprinkler height has a better effect on the temperature above the fire source,the temperature of the upper flue gas layer,and the concentration of the flue gas.Moreover,when the sprinkler is spread over thewhole transformer,the cooling effect on both the temperature above the fire source and the temperature of the upper flue gas layer is good,whereas the change in the concentration of the flue gas above the fire source is not obvious compared to the case where the sprinkler is not fully spread. 展开更多
关键词 Transformer fire high-pressure water mist TEMPERATURE flue gas concentration
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Electronic Instability of Kagome Metal CsV_(3)Sb_(5) in the 2×2×2 Charge Density Wave State
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作者 朱红恩 李彤瑞 +14 位作者 喻芳航 李昱良 王盛 吴云波 刘站锋 尚政明 崔胜涛 刘毅 张国斌 张李东 王震宇 吴涛 应剑俊 陈仙辉 孙喆 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第4期56-61,共6页
Recently discovered kagome metals AV_(3)Sb_(5)(A=K,Rb,and Cs)provide an ideal platform to study the correlation among nontrivial band topology,unconventional charge density wave(CDW),and superconductivity.The evolutio... Recently discovered kagome metals AV_(3)Sb_(5)(A=K,Rb,and Cs)provide an ideal platform to study the correlation among nontrivial band topology,unconventional charge density wave(CDW),and superconductivity.The evolution of electronic structures associated with the change of lattice modulations is crucial for understanding of the CDW mechanism,with the combination of angle-resolved photoemission spectroscopy(ARPES)measurements and density functional theory calculations,we investigate how band dispersions change with the increase of lattice distortions.In particular,we focus on the electronic states around M point,where the van Hove singularities are expected to play crucial roles in the CDW transition.Previous ARPES studies reported a spectral weight splitting of the van Hove singularity around M point,which is associated with the 3D lattice modulations.Our studies reveal that this“splitting”can be connected to the two van Hove singularities at k_(z)=0 and k_(z)=π/c in the normal states.When the electronic system enters into the CDW state,both van Hove singularities move down.Such novel properties are important for understanding of the CDW transition. 展开更多
关键词 transition SPLITTING LATTICE
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Flow Direction Level Traffic Flow Prediction Based on a GCN-LSTM Combined Model
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作者 Fulu Wei Xin Li +3 位作者 Yongqing Guo zhenyu wang Qingyin Li Xueshi Ma 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2001-2018,共18页
Traffic flow prediction plays an important role in intelligent transportation systems and is of great significance in the applications of traffic control and urban planning.Due to the complexity of road traffic flow d... Traffic flow prediction plays an important role in intelligent transportation systems and is of great significance in the applications of traffic control and urban planning.Due to the complexity of road traffic flow data,traffic flow prediction has been one of the challenging tasks to fully exploit the spatiotemporal characteristics of roads to improve prediction accuracy.In this study,a combined flow direction level traffic flow prediction graph convolutional network(GCN)and long short-term memory(LSTM)model based on spatiotemporal characteristics is proposed.First,a GCN model is employed to capture the topological structure of the data graph and extract the spatial features of road networks.Additionally,due to the capability to handle long-term dependencies,the longterm memory is used to predict the time series of traffic flow and extract the time features.The proposed model is evaluated using real-world data,which are obtained from the intersection of Liuquan Road and Zhongrun Avenue in the Zibo High-Tech Zone of China.The results show that the developed combined GCNLSTM flow direction level traffic flow prediction model can perform better than the single models of the LSTM model and GCN model,and the combined ARIMA-LSTM model in traffic flow has a strong spatiotemporal correlation. 展开更多
关键词 Flow direction level traffic flow forecasting spatiotemporal characteristics graph convolutional network short-and long-termmemory network
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Analysis on the Durability of Hybrid Polymer Composites for Power FGD System 被引量:1
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作者 zhenyu wang Lijie Xiu +3 位作者 Enhou Han Yunhe Zhang Yongan Zhao Ming Liu 《Journal of Power and Energy Engineering》 2016年第3期1-8,共8页
The corrosion condition of flue gas desulfurization (FGD) equipment for the coal-fired power plant was defined as the strong corrosion grade. The lining system of hybrid polymer composite was used in internal cylinder... The corrosion condition of flue gas desulfurization (FGD) equipment for the coal-fired power plant was defined as the strong corrosion grade. The lining system of hybrid polymer composite was used in internal cylinder of steel chimney, and a corrosion-resistant and heat-resistant protective layer was formed on the metal surface. The corrosion-resistant and ageing-resistant properties of hybrid polymer composite prepared at low temperature after four years of practical use were investigated by differential scanning calorimeter (DSC), scanning electron microscopy (SEM) and measurement of gravimetric variation, contact angle, abrasion resistance, bonding strength and tensile strength. The properties of hybrid polymer composites prepared at 25℃ and –15℃ were comparatively analyzed in the paper. 展开更多
关键词 Coal-Fired Power Plant Flue Gas Desulfurization Hybrid Polymer Composite DURABILITY Corrosion Resistance
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一维光子晶体能带结构的电光特性研究 被引量:1
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作者 李志鹏 武校刚 +2 位作者 高悦豪 王震宇 麻鸿祥 《光电子》 2018年第3期123-130,共8页
采用有限元法对一维掺镧锆钛酸铅光子晶体的能带特性进行分析。当给一维掺镧锆钛酸铅光子晶体施以外加电场时,由于介质掺镧锆钛酸铅的电光效应引起折射率变化,使得一维掺镧锆钛酸铅光子晶体的能带结构发生变化。详细分析了外加电场变化... 采用有限元法对一维掺镧锆钛酸铅光子晶体的能带特性进行分析。当给一维掺镧锆钛酸铅光子晶体施以外加电场时,由于介质掺镧锆钛酸铅的电光效应引起折射率变化,使得一维掺镧锆钛酸铅光子晶体的能带结构发生变化。详细分析了外加电场变化对一维掺镧锆钛酸铅光子晶体的禁带结构特性的影响,禁带的中心波长及禁带宽度的变化量与电场呈四次函数关系。 展开更多
关键词 有限元法 一维锆钛酸铅镧光子晶体 电场 电光效应 能带结构
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LiNbO3-coated LiNi0.8Co0.1Mn0.1O2 cathode with high discharge capacity and rate performance for all-solid-state lithium battery 被引量:13
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作者 Xuelei Li Liubing Jin +5 位作者 Dawei Song Hongzhou Zhang Xixi Shi zhenyu wang Lianqi Zhang Lingyun Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期39-45,I0002,共8页
In order to obtain high power density,energy density and safe energy storage lithium ion batteries(LIB)to meet growing demand for electronic products,oxide cathodes have been widely explored in all-solidstate lithium ... In order to obtain high power density,energy density and safe energy storage lithium ion batteries(LIB)to meet growing demand for electronic products,oxide cathodes have been widely explored in all-solidstate lithium batteries(ASSLB)using sulfide solid electrolyte.However,the electrochemical performances are still not satisfactory,due to the high interfacial resistance caused by severe interfacial instability between sulfide solid electrolyte and oxide cathode,especially Ni-rich oxide cathodes,in charge-discharge process.Ni-rich LiNi0.8Co0.1Mn0.1O2(NCM811)material at present is one of the most key cathode candidates to achieve the high energy density up to 300 Wh kg^-1 in liquid LIB,but rarely investigated in ASSLB using sulfide electrolyte.To design the stable interface between NCM811 and sulfide electrolyte should be extremely necessary.In this work,in view of our previous work,LiNbO3 coating with about 1 wt% content is adopted to improve the interfacial stability and the electrochemical performances of NCM811 cathode in ASSLB using Li10GeP2S12 solid electrolyte.Consequently,LiNbO3-coated NCM811 cathode displays the higher discharge capacity and rate performance than the reported oxide electrodes in ASSLB using sulfide solid electrolyte to our knowledge. 展开更多
关键词 All-solid-state lithium battery Sulfide electrolyte LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 LiNbO_3 Electrochemical performances
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Artificial Intelligence Applications in the Development of Autonomous Vehicles:A Survey 被引量:22
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作者 Yifang Ma zhenyu wang +1 位作者 Hong Yang Lin Yang 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第2期315-329,共15页
The advancement of artificial intelligence(AI)has truly stimulated the development and deployment of autonomous vehicles(AVs)in the transportation industry.Fueled by big data from various sensing devices and advanced ... The advancement of artificial intelligence(AI)has truly stimulated the development and deployment of autonomous vehicles(AVs)in the transportation industry.Fueled by big data from various sensing devices and advanced computing resources,AI has become an essential component of AVs for perceiving the surrounding environment and making appropriate decision in motion.To achieve goal of full automation(i.e.,self-driving),it is important to know how AI works in AV systems.Existing research have made great efforts in investigating different aspects of applying AI in AV development.However,few studies have offered the research community a thorough examination of current practices in implementing AI in AVs.Thus,this paper aims to shorten the gap by providing a comprehensive survey of key studies in this research avenue.Specifically,it intends to analyze their use of AIs in supporting the primary applications in AVs:1)perception;2)localization and mapping;and 3)decision making.It investigates the current practices to understand how AI can be used and what are the challenges and issues associated with their implementation.Based on the exploration of current practices and technology advances,this paper further provides insights into potential opportunities regarding the use of AI in conjunction with other emerging technologies:1)high definition maps,big data,and high performance computing;2)augmented reality(AR)/virtual reality(VR)enhanced simulation platform;and 3)5G communication for connected AVs.This paper is expected to offer a quick reference for researchers interested in understanding the use of AI in AV research. 展开更多
关键词 Artificial intelligence(AI) autonomous vehicles(AVs) deep learning(DL) motion planning PERCEPTION SELF-DRIVING
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Dynamic Fracture Analysis for Shale Material by Peridynamic Modelling 被引量:4
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作者 Zhanqi Cheng zhenyu wang Zhongtao Luo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第3期509-527,共19页
In this work,a bond-based peridynamics(PD)model was built to analyze the dynamic fracture of shale material.Both the the convergence studies and the result of dynamic crack propagation were presented.As well-known,cra... In this work,a bond-based peridynamics(PD)model was built to analyze the dynamic fracture of shale material.Both the the convergence studies and the result of dynamic crack propagation were presented.As well-known,crack propagation,aggregation,and bifurcation play an critical role in the failure analysis of brittle materials such as shale.The dynamic crack propagation and branching analysis of shale by using the PD method were discussed.Firstly,the valid and accuracy of the PD model for the rock materials was verified by comparing with the existed numerical results.Secondly,we discussed the convergence both with uniform grid refinement(m-convergence)and decreasing the peridynamics horizon(δ-convergence).Then the shale material with two pre-crack under uniaxial compression using the present PD model were discussed,and the influence of the different angle of flaws on the behavior of crack propagation was also analyzed.The results shows that both the loading conditions and the angle of flaws can influences the crack propagation in shale. 展开更多
关键词 PERIDYNAMICS SHALE DYNAMIC FRACTURE CRACK PROPAGATION DYNAMIC loads
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Effects of dietary fiber content and different fiber-rich ingredients on endogenous loss of fat and fatty acids in growing pigs 被引量:3
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作者 Yifan Chen zhenyu wang +5 位作者 Jian Ding Dongxu Ming Wenhui wang Zhaoning Jiang Ling Liu Fenglai wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第3期745-758,共14页
Background: Determination of the endogenous loss of fat(ELF) is used to adjust for the estimation of true total tract digestibility(TTTD) of fat in diets and ingredients.Any factor which affected ELF may further affec... Background: Determination of the endogenous loss of fat(ELF) is used to adjust for the estimation of true total tract digestibility(TTTD) of fat in diets and ingredients.Any factor which affected ELF may further affect the digestibility of fat,including sources and concentrations of fat and fiber in the diet.There are some reports of determining the ELF using regression methods based on different levels of fat intake,while reports on effects of dietary fiber content and different fiber-rich ingredients in pig diets on ELF are very limited.Therefore,the objective of this study was to determine the effects of dietary fiber content and different fiber-rich ingredients on endogenous losses of fat and fatty acids at the end of ileum and throughout the entire intestinal tract in growing pigs.Methods: In Exp.1,the effect of fiber content on endogenous loss of fat was determined using six growing pigs(Duroc × Landrace × Yorkshire;27.6 ± 2.4 kg),fitted with a T-cannula at the end of ileum.The experimental design was a 6 × 6 complete Latin square design with six periods of feeding and six diets.The six experimental fat-free diets were formulated to include graded levels of neutral detergent fiber(NDF)(0,40,80,120,160 and 200 g/kg) and soybean hull(SH) was the only fiber source,providing 0,75,150,225,300 and 375 g/kg,respectively.Chromic oxide was included at4 g/kg in all diets as an indigestible marker.In Exp.2,six crossbred growing barrows(27.6 ± 1.6 kg) were used and the experimental design was the same as for Exp.1.The six fat-free diets were formulated to include six common fiber-rich ingredients and the concentration of NDF was 100 g/kg.The six fiber-rich ingredients were defatted rice bran(DRB),sugar beet pulp(SBP),rice hull(RH),corn germ meal(CGM),SH and wheat bran(WB) and they were fed at represented250,270,145,250,170 and 280 g/kg in the diet,respectively.Results: In Exp.1,the endogenous loss of fatty acids profile did not change as dietary NDF increased in growing pigs.The endogenous losses of fat,C16:0,C18:0,C18:1,C18:2,total unsaturated fatty acids(UFA) and total saturated fatty acids(SFA) in growing pigs at the end of ileum and throughout the entire intestinal tract increased linearly as NDF content of diets increased.The endogenous losses of fat,as well as C16:0 and C18:0 throughout the entire intestinal tract also increased quadratically as NDF content of diets increased.The ELF increased from 0.71 to 3.14 g/kg of dry matter intake(DMI) and 0.56 to 8.21 g/kg DMI at the end of ileum and throughout the entire intestinal tract in growing pigs,respectively.The ELF occurred in the hindgut except for the growing pigs fed 0 and 4% NDF in their diets.The endogenous losses of C16:0 and UFA occurred primarily in the upper regions of the gut and the greatest endogenous losses of C18:0 occurred in the hindgut.The endogenous losses of fat,individual SFA and total SFA throughout the entire intestinal tract were much greater than that at the end of ileum.However,the endogenous losses of individual UFA and total UFA were less throughout the intestinal tract than at the end of ileum.In Exp.2,the endogenous losses of fat at the end of ileum were greater in growing pigs fed CGM or WB diets.The endogenous loss of fatty acids profile changed to a slight degree at the end of ileum that the endogenous loss of UFA(particularly C18:1 and C18:2) in growing pigs fed CGM or WB diets were greater(P < 0.01) than that for the other four diets.The greatest(P < 0.01) endogenous loss of SFA(particularly C18:0) was in growing pigs fed the RH diet.The endogenous losses of fat,C16:0,C18:0 and SFA over the entire intestinal tract were much greater in growing pigs fed CGM or WB diets,whereas the lowest values were in growing pigs fed DRB diet.The ELF at the end of ileum in growing pigs fed CGM or WB diets were 3.50 or 4.17 g/kg DMI,respectively,and the ELF over the entire intestinal tract was 7.23 or 7.38 g/kg DMI.The contribution in percentage of ELF in the upper gut was greater than that in the hindgut of growing pigs fed DRB and RH diets,while the ELF in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.On the whole,the endogenous losses of C18:1 and C18:2 throughout the entire intestinal tract in growing pigs fed the six fiber-rich ingredients diets were less than losses at the end of ileum,whereas the endogenous loss of fat,C16:0,C18:0 and SFA were greater throughout the intestinal tract than at the end of ileum.Conclusion: The profile of loss in endogenous fatty acids did not change as dietary NDF increased in growing pigs and the endogenous losses of fatty acids(C16:0,C18:0,C18:1 and C18:2) fat,UFA and SFA increased linearly as NDF content increased in the diets of pigs.The endogenous losses of fat or fatty acids at the end of ileum were greater in growing pigs fed RH,CGM or WB diets.The endogenous losses of fat,fatty acids(C16:0 and C18:0) and SFA were greater over the entire intestinal tract in pigs fed CGM or WB diet,while these values were the lowest in growing pigs fed the DRB diet.The contribution in percentage losses of fat in the upper gut were greater than in the hindgut of growing pigs fed DRB and RH diets,while the contribution of losses of fat in the upper gut and hindgut were equal in growing pigs fed SBP,CGM and WB diets.In addition,the endogenous loss of individual or total UFA was less over the entire intestinal tract of growing pigs fed fiber diets than that at the end of ileum,and the greatest endogenous losses of fat,individual or total SFA were over the entire intestinal tract.Therefore,differences in fiber content and the nature of fiber-rich ingredients in diets of pigs have different effects to the endogenous losses of fat or fatty acids.Considering the requirement of fat or fatty acids of pigs,careful attention must be paid that the endogenous losses of fat and fatty acids when fiber ingredients are used in diets of pigs. 展开更多
关键词 ENDOGENOUS LOSS FAT Fatty acids FIBER content Fiber-rich INGREDIENTS Growing pigs
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