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Unconventional geometric logic gate in a strong-driving-assisted multi-mode cavity
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作者 潘长宁 杨迪武 +1 位作者 赵学辉 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期103-109,共7页
We propose a scheme to implement an unconventional geometric logic gate separately in a two-mode cavity and a multi-mode cavity assisted by a strong classical driving field. The effect of the cavity decay is included ... We propose a scheme to implement an unconventional geometric logic gate separately in a two-mode cavity and a multi-mode cavity assisted by a strong classical driving field. The effect of the cavity decay is included in the investigation. The numerical calculation is carried out, and the result shows that our scheme is more tolerant to cavity decay than the previous one because the time consumed for finishing the logic gate is doubly reduced. 展开更多
关键词 unconventional geometric gate multi-mode cavity cavity decay
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Optimization Control of Multi-Mode Coupling All-Wheel Drive System for Hybrid Vehicle
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作者 Lipeng Zhang Zijian Wang +1 位作者 Liandong Wang Changan Ren 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期340-355,共16页
The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy... The all-wheel drive(AWD)hybrid system is a research focus on high-performance new energy vehicles that can meet the demands of dynamic performance and passing ability.Simultaneous optimization of the power and economy of hybrid vehicles becomes an issue.A unique multi-mode coupling(MMC)AWD hybrid system is presented to realize the distributed and centralized driving of the front and rear axles to achieve vectored distribution and full utilization of the system power between the axles of vehicles.Based on the parameters of the benchmarking model of a hybrid vehicle,the best model-predictive control-based energy management strategy is proposed.First,the drive system model was built after the analysis of the MMC-AWD’s drive modes.Next,three fundamental strategies were established to address power distribution adjustment and battery SOC maintenance when the SOC changed,which was followed by the design of a road driving force observer.Then,the energy consumption rate in the average time domain was processed before designing the minimum fuel consumption controller based on the equivalent fuel consumption coefficient.Finally,the advantage of the MMC-AWD was confirmed by comparison with the dynamic performance and economy of the BYD Song PLUS DMI-AWD.The findings indicate that,in comparison to the comparative hybrid system at road adhesion coefficients of 0.8 and 0.6,the MMC-AWD’s capacity to accelerate increases by 5.26%and 7.92%,respectively.When the road adhesion coefficient is 0.8,0.6,and 0.4,the maximum climbing ability increases by 14.22%,12.88%,and 4.55%,respectively.As a result,the dynamic performance is greatly enhanced,and the fuel savings rate per 100 km of mileage reaches 12.06%,which is also very economical.The proposed control strategies for the new hybrid AWD vehicle can optimize the power and economy simultaneously. 展开更多
关键词 Hybrid vehicle All-wheel drive multi-mode coupling Energy management Model predictive control
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Fake News Detection Based on Text-Modal Dominance and Fusing Multiple Multi-Model Clues
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作者 Li fang Fu Huanxin Peng +1 位作者 Changjin Ma Yuhan Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4399-4416,共18页
In recent years,how to efficiently and accurately identify multi-model fake news has become more challenging.First,multi-model data provides more evidence but not all are equally important.Secondly,social structure in... In recent years,how to efficiently and accurately identify multi-model fake news has become more challenging.First,multi-model data provides more evidence but not all are equally important.Secondly,social structure information has proven to be effective in fake news detection and how to combine it while reducing the noise information is critical.Unfortunately,existing approaches fail to handle these problems.This paper proposes a multi-model fake news detection framework based on Tex-modal Dominance and fusing Multiple Multi-model Cues(TD-MMC),which utilizes three valuable multi-model clues:text-model importance,text-image complementary,and text-image inconsistency.TD-MMC is dominated by textural content and assisted by image information while using social network information to enhance text representation.To reduce the irrelevant social structure’s information interference,we use a unidirectional cross-modal attention mechanism to selectively learn the social structure’s features.A cross-modal attention mechanism is adopted to obtain text-image cross-modal features while retaining textual features to reduce the loss of important information.In addition,TD-MMC employs a new multi-model loss to improve the model’s generalization ability.Extensive experiments have been conducted on two public real-world English and Chinese datasets,and the results show that our proposed model outperforms the state-of-the-art methods on classification evaluation metrics. 展开更多
关键词 Fake news detection cross-modal attention mechanism multi-modal fusion social network transfer learning
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A Multi-mode Electronic Load Sensing Control Scheme with Power Limitation and Pressure Cut-off for Mobile Machinery
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作者 Min Cheng Bolin Sun +1 位作者 Ruqi Ding Bing Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第1期157-170,共14页
In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are ... In mobile machinery,hydro-mechanical pumps are increasingly replaced by electronically controlled pumps to improve the automation level,but diversified control functions(e.g.,power limitation and pressure cut-off)are integrated into the electronic controller only from the pump level,leading to the potential instability of the overall system.To solve this problem,a multi-mode electrohydraulic load sensing(MELS)control scheme is proposed especially considering the switching stability from the system level,which includes four working modes of flow control,load sensing,power limitation,and pressure control.Depending on the actual working requirements,the switching rules for the different modes and the switching direction(i.e.,the modes can be switched bilaterally or unilaterally)are defined.The priority of different modes is also defined,from high to low:pressure control,power limitation,load sensing,and flow control.When multiple switching rules are satisfied at the same time,the system switches to the control mode with the highest priority.In addition,the switching stability between flow control and pressure control modes is analyzed,and the controller parameters that guarantee the switching stability are obtained.A comparative study is carried out based on a test rig with a 2-ton hydraulic excavator.The results show that the MELS controller can achieve the control functions of proper flow supplement,power limitation,and pressure cut-off,which has good stability performance when switching between different control modes.This research proposes the MELS control method that realizes the stability of multi-mode switching of the hydraulic system of mobile machinery under different working conditions. 展开更多
关键词 Hydraulic control Load sensing multi-mode Power limitation Mobile machinery
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Web Layout Design of Large Cavity Structures Based on Topology Optimization 被引量:1
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作者 Xiaoqiao Yang Jialiang Sun Dongping Jin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2665-2689,共25页
Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas... Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas become a focal point for contemporary researchers. Therefore, this paper aims to investigate the topologyoptimization of large cavity structures as a means to enhance their performance, safety, and efficiency. By usingthe variable density method, lightweight design is achieved without compromising structural strength. Theoptimization model considers both concentrated and distributed loads, and utilizes techniques like sensitivityfiltering and projection to obtain a robust optimized configuration. The mechanical properties are checked bycomparing the stress distribution and displacement of the unoptimized and optimized structures under the sameload. The results confirm that the optimized structures exhibit improved mechanical properties, thus offering keyinsights for engineering lightweight, high-strength large cavity structures. 展开更多
关键词 Topology optimization lightweight design web layout design cavity structure
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Non-volatile dynamically switchable color display via chalcogenide stepwise cavity resonators 被引量:1
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作者 Kuan Liu Zhenyuan Lin +2 位作者 Bing Han Minghui Hong Tun Cao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期16-27,共12页
High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic switching... High-resolution multi-color printing relies upon pixelated optical nanostructures,which is crucial to promote color display by producing nonbleaching colors,yet requires simplicity in fabrication and dynamic switching.Antimony trisulfide(Sb_(2)S_(3))is a newly rising chalcogenide material that possesses prompt and significant transition of its optical characteristics in the visible region between amorphous and crystalline phases,which holds the key to color-varying devices.Herein,we proposed a dynamically switchable color printing method using Sb_(2)S_(3)-based stepwise pixelated Fabry-Pérot(FP)cavities with various cavity lengths.The device was fabricated by employing a direct laser patterning that is a less timeconsuming,more approachable,and low-cost technique.As switching the state of Sb_(2)S_(3) between amorphous and crystalline,the multi-color of stepwise pixelated FP cavities can be actively changed.The color variation is due to the profound change in the refractive index of Sb_(2)S_(3) over the visible spectrum during its phase transition.Moreover,we directly fabricated sub-50 nm nano-grating on ultrathin Sb_(2)S_(3) laminate via microsphere 800-nm femtosecond laser irradiation in far field.The minimum feature size can be further decreased down to~45 nm(λ/17)by varying the thickness of Sb_(2)S_(3) film.Ultrafast switchable Sb_(2)S_(3) photonic devices can take one step toward the next generation of inkless erasable papers or displays and enable information encryption,camouflaging surfaces,anticounterfeiting,etc.Importantly,our work explores the prospects of rapid and rewritable fabrication of periodic structures with nano-scale resolution and can serve as a guideline for further development of chalcogenide-based photonics components. 展开更多
关键词 TUNABLE color displays Fabry-Pérot cavity resonators color printing chalcogenide materials
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Multi-mode Multi-frequency GNSS-IR Combination System for Sea Level Retrieval
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作者 Wenyue CHE Xiaolei WANG +1 位作者 Xiufeng HE Jin LIU 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第2期32-39,共8页
With the development of Global Navigation Satellite Systems(GNSS),geodetic GNSS receivers have been utilized to monitor sea levels using GNSS-Interferometry Reflectometry(GNSS-IR)technology.The multi-mode,multi-freque... With the development of Global Navigation Satellite Systems(GNSS),geodetic GNSS receivers have been utilized to monitor sea levels using GNSS-Interferometry Reflectometry(GNSS-IR)technology.The multi-mode,multi-frequency signals of GPS,GLONASS,Galileo,and Beidou can be used for GNSS-IR sea level retrieval,but combining these retrievals remains problematic.To address this issue,a GNSS-IR sea level retrieval combination system has been developed,which begins by analyzing error sources in GNSS-IR sea level retrieval and establishing and solving the GNSS-IR retrieval equation.This paper focuses on two key points:time window selection and equation stability.The stability of the retrieval combination equations is determined by the condition number of the coefficient matrix within the time window.The impact of ill-conditioned coefficient matrices on the retrieval results is demonstrated using an extreme case of SNR data with only ascending or descending trajectories.After determining the time window and removing ill-conditioned equations,the multi-mode,multi-frequency GNSS-IR retrieval is performed.Results from three International GNSS Service(IGS)stations show that the combination method produces high-precision,high-resolution,and high-reliability sea level retrieval combination sequences. 展开更多
关键词 GNSS-IR sea level retrieval multi-mode multi-frequency combination equation stability
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Method of Multi-Mode Sensor Data Fusion with an Adaptive Deep Coupling Convolutional Auto-Encoder
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作者 Xiaoxiong Feng Jianhua Liu 《Journal of Sensor Technology》 2023年第4期69-85,共17页
To address the difficulties in fusing multi-mode sensor data for complex industrial machinery, an adaptive deep coupling convolutional auto-encoder (ADCCAE) fusion method was proposed. First, the multi-mode features e... To address the difficulties in fusing multi-mode sensor data for complex industrial machinery, an adaptive deep coupling convolutional auto-encoder (ADCCAE) fusion method was proposed. First, the multi-mode features extracted synchronously by the CCAE were stacked and fed to the multi-channel convolution layers for fusion. Then, the fused data was passed to all connection layers for compression and fed to the Softmax module for classification. Finally, the coupling loss function coefficients and the network parameters were optimized through an adaptive approach using the gray wolf optimization (GWO) algorithm. Experimental comparisons showed that the proposed ADCCAE fusion model was superior to existing models for multi-mode data fusion. 展开更多
关键词 multi-mode Data Fusion Coupling Convolutional Auto-Encoder Adaptive Optimization Deep Learning
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Design and high-power testing of offline conditioning cavity for CiADS RFQ high-power coupler
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作者 Ruo-Xu Wang Yuan He +6 位作者 Long-Bo Shi Chen-Xing Li Zong-Heng Xue Tian-Cai Jiang Xian-Bo Xu Lie-Peng Sun Zhou-Li Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期18-27,共10页
To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity feat... To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity features two coupling ports and two tuners,operating at a frequency of 162.5 MHz with a tuning range of 3.2 MHz.Adjusting the installation angle of the coupling ring and the insertion depth of the tuner helps minimize cavity losses.We performed electromagnetic structural and multiphysics simulations,revealing a minimal theoretical power loss of 4.3%.However,when the cavity frequency varied by110 kHz,theoretical power losses increased to10%,necessitating constant tuner adjustments during conditioning.Multiphysics simulations indicated that increased cavity temperature did not affect frequency variation.Upon completion of the offline high-power conditioning platform,we measured the transmission performance,revealing a power loss of 6.3%,exceeding the theoretical calculation.Conditioning utilized efficient automatic range scanning and standing wave resonant methods.To fully condition the power coupler,a 15°phase difference between two standing wave points in the condition-ing system was necessary.Notably,the maximum continuous wave power surpassed 20 kW,exceeding the expected target. 展开更多
关键词 RFQ cavity Power coupler Offline conditioning Resonant cavity
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Finesse measurement for high-power optical enhancement cavity
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作者 陆心怡 柳兴 +3 位作者 田其立 王焕 汪嘉俊 颜立新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期414-421,共8页
Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the a... Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications. 展开更多
关键词 optical enhancement cavity finesse measurement cavity ring-down ringing effect
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A Hand Features Based Fusion Recognition Network with Enhancing Multi-Modal Correlation
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作者 Wei Wu Yuan Zhang +2 位作者 Yunpeng Li Chuanyang Li YanHao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期537-555,共19页
Fusing hand-based features in multi-modal biometric recognition enhances anti-spoofing capabilities.Additionally,it leverages inter-modal correlation to enhance recognition performance.Concurrently,the robustness and ... Fusing hand-based features in multi-modal biometric recognition enhances anti-spoofing capabilities.Additionally,it leverages inter-modal correlation to enhance recognition performance.Concurrently,the robustness and recognition performance of the system can be enhanced through judiciously leveraging the correlation among multimodal features.Nevertheless,two issues persist in multi-modal feature fusion recognition:Firstly,the enhancement of recognition performance in fusion recognition has not comprehensively considered the inter-modality correlations among distinct modalities.Secondly,during modal fusion,improper weight selection diminishes the salience of crucial modal features,thereby diminishing the overall recognition performance.To address these two issues,we introduce an enhanced DenseNet multimodal recognition network founded on feature-level fusion.The information from the three modalities is fused akin to RGB,and the input network augments the correlation between modes through channel correlation.Within the enhanced DenseNet network,the Efficient Channel Attention Network(ECA-Net)dynamically adjusts the weight of each channel to amplify the salience of crucial information in each modal feature.Depthwise separable convolution markedly reduces the training parameters and further enhances the feature correlation.Experimental evaluations were conducted on four multimodal databases,comprising six unimodal databases,including multispectral palmprint and palm vein databases from the Chinese Academy of Sciences.The Equal Error Rates(EER)values were 0.0149%,0.0150%,0.0099%,and 0.0050%,correspondingly.In comparison to other network methods for palmprint,palm vein,and finger vein fusion recognition,this approach substantially enhances recognition performance,rendering it suitable for high-security environments with practical applicability.The experiments in this article utilized amodest sample database comprising 200 individuals.The subsequent phase involves preparing for the extension of the method to larger databases. 展开更多
关键词 BIOMETRICS multi-modAL CORRELATION deep learning feature-level fusion
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A Comprehensive Survey on Deep Learning Multi-Modal Fusion:Methods,Technologies and Applications
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作者 Tianzhe Jiao Chaopeng Guo +2 位作者 Xiaoyue Feng Yuming Chen Jie Song 《Computers, Materials & Continua》 SCIE EI 2024年第7期1-35,共35页
Multi-modal fusion technology gradually become a fundamental task in many fields,such as autonomous driving,smart healthcare,sentiment analysis,and human-computer interaction.It is rapidly becoming the dominant resear... Multi-modal fusion technology gradually become a fundamental task in many fields,such as autonomous driving,smart healthcare,sentiment analysis,and human-computer interaction.It is rapidly becoming the dominant research due to its powerful perception and judgment capabilities.Under complex scenes,multi-modal fusion technology utilizes the complementary characteristics of multiple data streams to fuse different data types and achieve more accurate predictions.However,achieving outstanding performance is challenging because of equipment performance limitations,missing information,and data noise.This paper comprehensively reviews existing methods based onmulti-modal fusion techniques and completes a detailed and in-depth analysis.According to the data fusion stage,multi-modal fusion has four primary methods:early fusion,deep fusion,late fusion,and hybrid fusion.The paper surveys the three majormulti-modal fusion technologies that can significantly enhance the effect of data fusion and further explore the applications of multi-modal fusion technology in various fields.Finally,it discusses the challenges and explores potential research opportunities.Multi-modal tasks still need intensive study because of data heterogeneity and quality.Preserving complementary information and eliminating redundant information between modalities is critical in multi-modal technology.Invalid data fusion methods may introduce extra noise and lead to worse results.This paper provides a comprehensive and detailed summary in response to these challenges. 展开更多
关键词 multi-modal fusion REPRESENTATION TRANSLATION ALIGNMENT deep learning comparative analysis
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Realization of an Adaptive Radiative Cooler with a Multilayer-Filter VO_(2)-Based Fabry-Pérot Cavity
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作者 谢恒立 殷怀远 范春珍 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期38-44,共7页
A high-performance adaptive radiative cooler comprising a multilayer-filter VO_(2)-based Fabry-Pérot(FP)cavity is proposed.The bottom FP cavity has four layers,VO_(2)/NaCl/PVC/Ag.Based on the phase transition of ... A high-performance adaptive radiative cooler comprising a multilayer-filter VO_(2)-based Fabry-Pérot(FP)cavity is proposed.The bottom FP cavity has four layers,VO_(2)/NaCl/PVC/Ag.Based on the phase transition of VO_(2),the average emissivity in the transparent window can be switched from 3.7%to 96.3%.Additionally,the average emissivity can also be adjusted with external strain to the PVC layer,providing another way to attain the desired cooling effect.An upper filter is included to block most of the solar radiation and provide a transmittance of 96.7% in the atmospheric window.At high temperature,the adaptive emitter automatically activates radiative cooling.The net cooling power is up to 156.4 W·m^(-2)at an ambient temperature of 303 K.Our adaptive emitter still exhibits stable selective emissivity at different incident angles and heat transfer coefficients.At low temperature,the radiative cooling automatically deactivates,and the average emissivity decreases to only 3.8%.Therefore,our work not only provides new insights into the design of high-performance adaptive radiative coolers but also advances the development of intelligent thermal management. 展开更多
关键词 EMISSIVITY cavity SWITCHED
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Towards trustworthy multi-modal motion prediction:Holistic evaluation and interpretability of outputs
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作者 Sandra Carrasco Limeros Sylwia Majchrowska +3 位作者 Joakim Johnander Christoffer Petersson MiguelÁngel Sotelo David Fernández Llorca 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第3期557-572,共16页
Predicting the motion of other road agents enables autonomous vehicles to perform safe and efficient path planning.This task is very complex,as the behaviour of road agents depends on many factors and the number of po... Predicting the motion of other road agents enables autonomous vehicles to perform safe and efficient path planning.This task is very complex,as the behaviour of road agents depends on many factors and the number of possible future trajectories can be consid-erable(multi-modal).Most prior approaches proposed to address multi-modal motion prediction are based on complex machine learning systems that have limited interpret-ability.Moreover,the metrics used in current benchmarks do not evaluate all aspects of the problem,such as the diversity and admissibility of the output.The authors aim to advance towards the design of trustworthy motion prediction systems,based on some of the re-quirements for the design of Trustworthy Artificial Intelligence.The focus is on evaluation criteria,robustness,and interpretability of outputs.First,the evaluation metrics are comprehensively analysed,the main gaps of current benchmarks are identified,and a new holistic evaluation framework is proposed.Then,a method for the assessment of spatial and temporal robustness is introduced by simulating noise in the perception system.To enhance the interpretability of the outputs and generate more balanced results in the proposed evaluation framework,an intent prediction layer that can be attached to multi-modal motion prediction models is proposed.The effectiveness of this approach is assessed through a survey that explores different elements in the visualisation of the multi-modal trajectories and intentions.The proposed approach and findings make a significant contribution to the development of trustworthy motion prediction systems for autono-mous vehicles,advancing the field towards greater safety and reliability. 展开更多
关键词 autonomous vehicles EVALUATION INTERPRETABILITY multi-modal motion prediction ROBUSTNESS trustworthy AI
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Self-consistent and precise measurement of time-dependent radiative albedo of gold based on specially symmetrical triple-cavity Hohlraum
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作者 Zhiyu Zhang Yang Zhao +19 位作者 Xiaoying Han Liling Li Bo Qing Lifei Hou Yulong Li YuXue Zhang Huan Zhang Xiangming Liu Bo Deng Gang Xiong Min Lv Tuo Zhu Chengwu Huang Tianming Song Yan Zhao Yingjie Li Lu Zhang Xufei Xie Jiyan Zhang Jiamin Yang 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第3期57-64,共8页
A self-consistent and precise method to determine the time-dependent radiative albedo,i.e.,the ratio of the reemission flux to the incident flux,for an indirect-drive inertial confinement fusion Hohlraum wall material... A self-consistent and precise method to determine the time-dependent radiative albedo,i.e.,the ratio of the reemission flux to the incident flux,for an indirect-drive inertial confinement fusion Hohlraum wall material is proposed.A specially designed symmetrical triple-cavity gold Hohlraum is used to create approximately constant and near-equilibrium uniform radiation with a peak temperature of 160 eV.The incident flux at the secondary cavity waist is obtained from flux balance analysis and from the shock velocity of a standard sample.The results agree well owing to the symmetrical radiation in the secondary cavity.A self-consistent and precise time-dependent radiative albedo is deduced from the reliable reemission flux and the incident flux,and the result from the shock velocity is found to have a smaller uncertainty than that from the multi-angle flux balance analysis,and also to agree well with the result of a simulation using the HYADES opacity. 展开更多
关键词 PRECISE cavity RADIATIVE
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High-frequency microwave cavity design for high-mass dark matter axion searches
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作者 张驰 王佳 +4 位作者 李春光 陈石广 程航 孙亮 吴云 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期87-94,共8页
The haloscope based on the TM_(010)mode cavity is a well-established technique for detecting QCD axions.However,the method has limitations in detecting high-mass axion due to significant volume loss in the high-freque... The haloscope based on the TM_(010)mode cavity is a well-established technique for detecting QCD axions.However,the method has limitations in detecting high-mass axion due to significant volume loss in the high-frequency cavity.Utilizing a higher-order mode cavity can effectively reduce the volume loss of the high-frequency cavity.The rotatable dielectric pieces as a tuning mechanism can compensate for the degradation of the form factor of the higher-order mode.Nevertheless,the introduction of dielectric causes additional volume loss.To address these issues,this paper proposes a novel design scheme by adding a central metal rod to the higher-order mode cavity tuned by dielectrics,which improves the performance of the haloscope due to the increased effective volume of the cavity detector.The superiority of the novel design is demonstrated by comparing its simulated performance with previous designs.Moreover,the feasibility of the scheme is verified by the full-wave simulation results of the mechanical design model. 展开更多
关键词 AXION haloscope microwave cavity
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Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator
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作者 Jens Müller Sebastian Leonow +2 位作者 Johannes Schulz Christian Hansen Martin Monnigmann 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1346-1353,共8页
This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this m... This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation. 展开更多
关键词 BACKFLOW Progressing cavity pump Virtual sensor WEAR
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Multi-dimension and multi-modal rolling mill vibration prediction model based on multi-level network fusion
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作者 CHEN Shu-zong LIU Yun-xiao +3 位作者 WANG Yun-long QIAN Cheng HUA Chang-chun SUN Jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3329-3348,共20页
Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction mode... Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction models do not consider the features contained in the data,resulting in limited improvement of model accuracy.To address these challenges,this paper proposes a multi-dimensional multi-modal cold rolling vibration time series prediction model(MDMMVPM)based on the deep fusion of multi-level networks.In the model,the long-term and short-term modal features of multi-dimensional data are considered,and the appropriate prediction algorithms are selected for different data features.Based on the established prediction model,the effects of tension and rolling force on mill vibration are analyzed.Taking the 5th stand of a cold mill in a steel mill as the research object,the innovative model is applied to predict the mill vibration for the first time.The experimental results show that the correlation coefficient(R^(2))of the model proposed in this paper is 92.5%,and the root-mean-square error(RMSE)is 0.0011,which significantly improves the modeling accuracy compared with the existing models.The proposed model is also suitable for the hot rolling process,which provides a new method for the prediction of strip rolling vibration. 展开更多
关键词 rolling mill vibration multi-dimension data multi-modal data convolutional neural network time series prediction
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Numerical study on the cavity dynamics for vertical water entries of twin spheres
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作者 Xu Wang Xujian Lyu +1 位作者 Ruisheng Sun Dongdong Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期459-472,共14页
In this study, a three dimensional(3D) numerical model of six-degrees-of-freedom(6DOF) is applied to simulate the water entries of twin spheres side-by-side at different lateral distances and time intervals.The turbul... In this study, a three dimensional(3D) numerical model of six-degrees-of-freedom(6DOF) is applied to simulate the water entries of twin spheres side-by-side at different lateral distances and time intervals.The turbulence structure is described using the shear-stress transport k-ω(SST k-ω) model, and the volume of fluid(VOF) method is used to track the complex air-liquid interface. The motion of spheres during water entry is simulated using an independent overset grid. The numerical model is verified by comparing the cavity evolution results from simulations and experiments. Numerical results reveal that the time interval between the twin water entries evidently affects cavity expansion and contraction behaviors in the radial direction. However, this influence is significantly weakened by increasing the lateral distance between the two spheres. In synchronous water entries, pressure is reduced on the midline of two cavities during surface closure, which is directly related to the cavity volume. The evolution of vortexes inside the two cavities is analyzed using a velocity vector field, which is affected by the lateral distance and time interval of water entries. 展开更多
关键词 Twin water entries Side-by-side cavity Numerical simulation
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Multi-modal knowledge graph inference via media convergence and logic rule
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作者 Feng Lin Dongmei Li +5 位作者 Wenbin Zhang Dongsheng Shi Yuanzhou Jiao Qianzhong Chen Yiying Lin Wentao Zhu 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期211-221,共11页
Media convergence works by processing information from different modalities and applying them to different domains.It is difficult for the conventional knowledge graph to utilise multi-media features because the intro... Media convergence works by processing information from different modalities and applying them to different domains.It is difficult for the conventional knowledge graph to utilise multi-media features because the introduction of a large amount of information from other modalities reduces the effectiveness of representation learning and makes knowledge graph inference less effective.To address the issue,an inference method based on Media Convergence and Rule-guided Joint Inference model(MCRJI)has been pro-posed.The authors not only converge multi-media features of entities but also introduce logic rules to improve the accuracy and interpretability of link prediction.First,a multi-headed self-attention approach is used to obtain the attention of different media features of entities during semantic synthesis.Second,logic rules of different lengths are mined from knowledge graph to learn new entity representations.Finally,knowledge graph inference is performed based on representing entities that converge multi-media features.Numerous experimental results show that MCRJI outperforms other advanced baselines in using multi-media features and knowledge graph inference,demonstrating that MCRJI provides an excellent approach for knowledge graph inference with converged multi-media features. 展开更多
关键词 logic rule media convergence multi-modal knowledge graph inference representation learning
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