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An Analysis of the Bidirectional Shaping Mechanism Between Short-Video Algorithms and Film Narrative Driven by the Attention Economy
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作者 Zhaoyang Dong Shibo Zhang 《Proceedings of Business and Economic Studies》 2025年第5期32-38,共7页
This study examines the bidirectional shaping mechanism between short-video algorithms and film narratives within the attention economy.It investigates how algorithmic logic influences cinematic storytelling and how f... This study examines the bidirectional shaping mechanism between short-video algorithms and film narratives within the attention economy.It investigates how algorithmic logic influences cinematic storytelling and how films,in turn,contribute to the aesthetic enhancement of short-video content.Drawing on Communication Accommodation Theory and Berry’s Acculturation Theory,along with case analyses and industry data,this research demonstrates that algorithms push films toward high-stimulus,fast-paced narrative patterns—characterized by increased shot density and structural fragmentation—to capture and retain viewer attention.Conversely,films counter this influence by supplying narratively deep and artistically refined content that elevates short-video aesthetics and encourages critical audience engagement.This dynamic reflects a process of mutual adaptation rather than one-sided dominance.The study concludes that such interaction signifies a broader restructuring of cultural production logic,facilitating cross-media convergence while simultaneously posing risks to cultural diversity due to the prioritization of high-traffic content.Balancing this relationship will require policy support,algorithmic transparency,and strengthened industry self-regulation to preserve artistic integrity and cultural ecosystem diversity. 展开更多
关键词 Short-video algorithm Film narrative Bidirectional shaping Cultural production logic Attention economy
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Integrating Value Shaping Into Task Design for Enhancing Ideological-Political Education in Foreign Language Courses
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作者 CHEN Yan-hui 《Sino-US English Teaching》 2025年第2期53-57,共5页
The construction of ideological-political education within foreign language courses requires an integrated approach that encompasses value shaping,knowledge transfer,and competence cultivation.A critical challenge in ... The construction of ideological-political education within foreign language courses requires an integrated approach that encompasses value shaping,knowledge transfer,and competence cultivation.A critical challenge in this domain is the effective design and implementation of tasks that instill values,while also synergizing with acquiring knowledge and enhancing competencies.This paper delves into the philosophical underpinnings and operational principles of value-shaping task design and its practical application within the context of foreign language teaching.Utilizing Contemporary College English(Integrated Coursebook 3)as a case study,the paper explores value shaping-based task design in ideological-political education of foreign language courses,with the aim of providing references for the construction of ideological-political education in foreign language teaching. 展开更多
关键词 value shaping ideological-political construction foreign language course task design
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Fishing Ship Trajectory Tracking Control Based on the Closed-Loop Gain Shaping Algorithm Under Rough Sea
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作者 SONG Chun-yu GUO Te-er SUI Jiang-hua 《China Ocean Engineering》 2025年第2期365-372,共8页
This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working... This paper proposes a separated trajectory tracking controller for fishing ships at sea state level 6 to solve the trajectory tracking problem of a fishing ship in a 6-level sea state,and to adapt to different working environments and safety requirements.The nonlinear feedback method is used to improve the closed-loop gain shaping algorithm.By introducing the sine function,the problem of excessive control energy of the system can be effectively solved.Moreover,an integral separation design is used to solve the influence of the integral term in conventional PID controllers on the transient performance of the system.In this paper,a common 32.98 m large fiberglass reinforced plastic(FRP)trawler is adopted for simulation research at the winds scale of Beaufort No.7.The results show that the track error is smaller than 3.5 m.The method is safe,feasible,concise and effective and has popularization value in the direction of fishing ship trajectory tracking control.This method can be used to improve the level of informatization and intelligence of fishing ships. 展开更多
关键词 trajectory tracking control nonlinear feedback control fishing ship closed-loop gain shaping algorithm rough sea
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Dynamic spatial beam shaping for ultrafast laser processing:a review
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作者 Cyril Mauclair Bahia Najih +2 位作者 Vincent Comte Florent Bourquard Martin Delaigue 《Opto-Electronic Science》 2025年第8期14-43,共30页
This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strate... This review examines the state-of-the-art in spatial manipulation of ultrafast laser processing using dynamic light modulators,with a particular focus on liquid crystal-based systems.We discuss phase modulation strategies and highlight the current limitations and challenges in surface and bulk processing.Specifically,we emphasize the delicate balance between high-fidelity beam shaping and energy efficiency,both critical for surface and bulk processing applications.Given the inherent physical limitations of spatial light modulators such as spatial resolution,fill factor,and phase modulation range.We explore techniques developed to bridge the gap between desired intensity distributions and actual experimental beam profiles.We present various laser light modulation technologies and the main algorithmic strategies for obtaining modulation patterns.The paper includes application examples across a wide range of fields,from surgery to surface structuring,cutting,bulk photo-inscription of optical functions,and additive manufacturing,highlighting the significant enhancements in processing speed and precision due to spatial beam shaping.The diverse applications and the technological limitations underscore the need for adapted modulation pattern calculation methods.We discuss several advancements addressing these challenges,involving both experimental and algorithmic developments,including the recent incorporation of artificial intelligence.Additionally,we cover recent progress in phase and pulse front control based on spatial modulators,which introduces an extra control parameter for light excitation with high potential for achieving more controlled processing outcomes. 展开更多
关键词 spatial light modulator ultrafast laser processing spatial beam shaping laser surface structuring laser bullk structuring
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Self-Adaptive LSAC-PID Approach Based on Lyapunov Reward Shaping for Mobile Robots
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作者 YU Xinyi XU Siyu +1 位作者 FAN Yuehai OU Linlin 《Journal of Shanghai Jiaotong university(Science)》 2025年第6期1085-1102,共18页
In order to solve the control problem of multiple-input multiple-output(MIMO)systems in complex and variable control environments,a model-free adaptive LSAC-PID method based on deep reinforcement learning(RL)is propos... In order to solve the control problem of multiple-input multiple-output(MIMO)systems in complex and variable control environments,a model-free adaptive LSAC-PID method based on deep reinforcement learning(RL)is proposed in this paper for automatic control of mobile robots.According to the environmental feedback,the RL agent of the upper controller outputs the optimal parameters to the lower MIMO PID controllers,which can realize the real-time PID optimal control.First,a model-free adaptive MIMO PID hybrid control strategy is presented to realize real-time optimal tuning of control parameters in terms of soft-actor-critic(SAC)algorithm,which is state-of-the-art RL algorithm.Second,in order to improve the RL convergence speed and the control performance,a Lyapunov-based reward shaping method for off-policy RL algorithm is designed,and a self-adaptive LSAC-PID tuning approach with Lyapunov-based reward is then determined.Through the policy evaluation and policy improvement of the soft policy iteration,the convergence and optimality of the proposed LSAC-PID algorithm are proved mathematically.Finally,based on the proposed reward shaping method,the reward function is designed to improve the system stability for the line-following robot.The simulation and experiment results show that the proposed adaptive LSAC-PID approach has good control performance such as fast convergence speed,high generalization and high real-time performance,and achieves real-time optimal tuning of MIMO PID parameters without the system model and control loop decoupling. 展开更多
关键词 multiple-input multiple-output(MIMO) PID tuning reinforcement learning(RL) Lyapunov-based reward shaping soft actor-critic(SAC) mobile robot
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Discussion on Artistry and Techniques of Role Shaping in Drama Performance
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作者 Ruixuan Liang 《Journal of Contemporary Educational Research》 2025年第5期326-331,共6页
Role shaping in dramatic performance is a fusion of art and skills,which involves the deep digging of character,the delicate expression of emotion,and the logical construction of behavior.Actors not only analyze the s... Role shaping in dramatic performance is a fusion of art and skills,which involves the deep digging of character,the delicate expression of emotion,and the logical construction of behavior.Actors not only analyze the script and understand the emotions of the role to create a multi-dimensional,three-dimensional character image,but also need to use the skills of sound,form,lines,and so on,to convey the role’s internal emotions and psychological changes.This process tests the artistic accomplishment and skill level of the actors,and requires them to have keen observation and rich imagination and creativity.Through the analysis of the role of Yu Ji in the Peking Opera Farewell My Concubine,it shows the deep integration of artistry and skill,highlighting the unique charm of dramatic performance. 展开更多
关键词 Role shaping Emotion expression Dramatic skill
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Assessment of Dependent Performance Shaping Factors in SPAR-H Based on Pearson Correlation Coefficient 被引量:2
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作者 Xiaoyan Su Shuwen Shang +2 位作者 Zhihui Xu Hong Qian Xiaolei Pan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1813-1826,共14页
With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in th... With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method. 展开更多
关键词 Reliability evaluation human reliability analysis SPAR-H performance shaping factors DEPENDENCE pearson correlation analysis
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The shaping of milk-flavored white tea:More than a change in appearance 被引量:1
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作者 Jiao Feng Weisu Tian +6 位作者 Jinyuan Wang Shuping Ye Guanjun Pan Bugui Yu Fang Wang Hongzheng Lin Zhilong Hao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第11期3912-3922,共11页
Tea’s popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor.This study employed targeted metabolomics and chemometrics to inv... Tea’s popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor.This study employed targeted metabolomics and chemometrics to investigate how shaping techniques affect the flavor of milk-flavored white tea(MFWT).The results showed that the tea cake sample with the shortest pressing time(Y90)has the highest amino acid content and milky aroma intensity.There were variations in amino acids,catechins,and soluble sugars among MFWT samples with different shaping techniques.The total contents of amino acids and catechins in tea cake sample(Y90)were significantly lower than those in the loose tea sample(SC)and bundle-like tea sample(SG),while the total sugar content was significantly higher than that in SC(P<0.05).Additionally,the content of volatiles presenting milky aroma(VIP&OAV>1)in Y90 remained lower relative to SC and SG(P<0.05),but the proportion was not different from that in SC and SG,minimally affecting the overall flavor.The short-time pressing method might be suitable for mass production of MFWT.These findings provide insights into improving the tightness of the appearance of MFWT with minimal impact on tea flavor. 展开更多
关键词 shaping milk-flavored white tea Camellia sinensis tea processing tea flavor
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Integrated high-performance and accurate shaping technology of low-cost powder metallurgy titanium alloys: A comprehensive review 被引量:1
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作者 Xuemeng Gan Shaofu Li +1 位作者 Shunyuan Xiao Yafeng Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期413-426,共14页
The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O ... The practical engineering applications of powder metallurgy (PM) Ti alloys produced through cold compaction and pressure-less sintering are impeded by poor sintering densification, embrittlement caused by excessive O impurities, and severe sintering deforma-tion resulting from the use of heterogeneous powder mixtures. This review presents a summary of our previous work on addressing the above challenges. Initially, we proposed a novel strategy using reaction-induced liquid phases to enhance sintering densification. Near- complete density (relative density exceeding 99%) was achieved by applying the above strategy and newly developed sintering aids. By focusing on the O-induced embrittlement issue, we determined the onset dissolution temperature of oxide films in the Ti matrix. On the basis of this finding, we established a design criterion for effective O scavengers that require reaction with oxide films before their dissol-ution. Consequently, a ductile PM Ti alloy was successfully obtained by introducing 0.3wt% NdB6 as the O scavenger. Lastly, a powder- coating strategy was adopted to address the sintering deformation issue. The ultrafine size and shell-like distribution characteristics of coating particles ensured rapid dissolution and homogeneity in the Ti matrix, thereby facilitating linear shrinkage during sintering. As a result, geometrically complex Ti alloy parts with high dimensional accuracy were fabricated by using the coated powder. Our fundament-al findings and related technical achievements enabled the development of an integrated production technology for the high-performance and accurate shaping of low-cost PM Ti alloys. Additionally, the primary engineering applications and progress in the industrialization practice of our developed technology are introduced in this review. 展开更多
关键词 powder metallurgy titanium sintering densification oxygen scavenging accurate shaping
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Joint Optimization of Precoding and Constellation Shaping for Faster-than-Nyquist Signaling
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作者 Kang Weimin 《China Communications》 SCIE CSCD 2024年第11期141-149,共9页
Faster-than-Nyquist(FTN)signaling is a potential scheme for the sixth generation(6G)communication system to improve the spectral efficiency(SE).In this paper,we propose a joint optimization algorithm of precoding and ... Faster-than-Nyquist(FTN)signaling is a potential scheme for the sixth generation(6G)communication system to improve the spectral efficiency(SE).In this paper,we propose a joint optimization algorithm of precoding and constellation shaping for FTN signaling,which is based on simulated optimization via the bare bones particle swarm optimization(BBPSO).The information-theoretical analysis and simulated error performance show that the proposed method is efficient,which can get a significant improvement in terms of average mutual information(AMI)and bit error rate(BER)performance.The simulated BER results verify the theoretical AMI analysis.Compared with the conventional regular 16QAM FTN scheme,when BER is at 10-5,the joint optimized scheme can obtain 0.50 dB and 0.60 dB performance gain with SE at 3.077 bits/s/Hz and 3.282 bits/s/Hz,respectively.Therefore,the proposed scheme is reliable,and thus suitable for the 6G communication. 展开更多
关键词 constellation shaping faster-than-Nyquist PRECODING spectral efficiency
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Tactical reward shaping for large-scale combat by multi-agent reinforcement learning
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作者 DUO Nanxun WANG Qinzhao +1 位作者 LYU Qiang WANG Wei 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1516-1529,共14页
Future unmanned battles desperately require intelli-gent combat policies,and multi-agent reinforcement learning offers a promising solution.However,due to the complexity of combat operations and large size of the comb... Future unmanned battles desperately require intelli-gent combat policies,and multi-agent reinforcement learning offers a promising solution.However,due to the complexity of combat operations and large size of the combat group,this task suffers from credit assignment problem more than other rein-forcement learning tasks.This study uses reward shaping to relieve the credit assignment problem and improve policy train-ing for the new generation of large-scale unmanned combat operations.We first prove that multiple reward shaping func-tions would not change the Nash Equilibrium in stochastic games,providing theoretical support for their use.According to the characteristics of combat operations,we propose tactical reward shaping(TRS)that comprises maneuver shaping advice and threat assessment-based attack shaping advice.Then,we investigate the effects of different types and combinations of shaping advice on combat policies through experiments.The results show that TRS improves both the efficiency and attack accuracy of combat policies,with the combination of maneuver reward shaping advice and ally-focused attack shaping advice achieving the best performance compared with that of the base-line strategy. 展开更多
关键词 deep reinforcement learning multi-agent reinforce-ment learning multi-agent combat unmanned battle reward shaping
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Asia-Pacific Regional Economic Cooperation Under the Reshaping of Global Production and Supply Chains
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作者 Liu Chenyang 《Contemporary World》 2024年第3期20-25,共6页
As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increas... As part of the important trends of the current development of the world economy,the reshaping of global industry and supply chains interacts with the intensified changes unprecedented in the past century in an increasingly close manner.“Benefit-sharing and risk-sharing”,the characteristics of global industry and supply chains,have a profound influence on the distribution of benefits among countries and the effectiveness of global economic governance. 展开更多
关键词 CHAINS intensified shaping
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Binary Phase Shaping and SHG Contrast Ratios
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作者 Tingyao Xiong 《Journal of Applied Mathematics and Physics》 2024年第8期3026-3035,共10页
Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relatio... Finding binary sequences with Large SHG ratios is very important in the field of ultrafast science, biomedical optics, high-resolution microscopy and label-free imaging. In this paper, we have demonstrated the relation between the SHG contrast ratio and the traditional Merit Factor values. And in the light from known results in Merit Factor Problems, we have shown that Legendre Sequences or Jacobi Sequences, are still the best candidates to obtain binary sequences with large SHG contrast ratios. The authors also discussed the SHG behaviors on some sequences obtained from cyclotomic classes over the finite field GF (2l) . 展开更多
关键词 Binary Phase shaping Binary Sequences SHG Contrast Ratio Merit Factor
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Azimuthal beam shaping in orbital angular momentum basis
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作者 Zhongzheng Lin Weihang Zhong +5 位作者 Lixun Wu Lin He Hongjia Chen Jianqi Hu Yujie Chen Siyuan Yu 《Advanced Photonics Nexus》 2024年第2期1-7,共7页
Shaping the light beam is always essential for laser technology and its applications.Among the shaping technologies,shaping the laser in its Fourier domain is a widely used and effective method,such as a pulse shaper,... Shaping the light beam is always essential for laser technology and its applications.Among the shaping technologies,shaping the laser in its Fourier domain is a widely used and effective method,such as a pulse shaper,or a 4f system with a phase mask or an iris in between.Orbital angular momentum(OAM)modes spectrum,the Fourier transform of the light field in azimuth,provides a perspective for shaping the light.Here,we propose and experimentally demonstrate a shaping strategy for the azimuthal field by modulating the complex amplitude of the OAM mode spectrum.The scheme utilizes multi-plane light conversion technology and consists only of a spatial light modulator and a mirror.Multiple functions,including beam rotating,beam splitting/combining in azimuth,and OAM mode filtering,are demonstrated.Our work provides a compact and programmable solution for modulating the OAM mode spectrum and shaping beams in azimuth. 展开更多
关键词 orbital angular momentum laser beam shaping multiplane light conversion structured light
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A study on the treatment of chloasma with moxibustion based on the theory of“Yang transforming Qi,and Yin shaping”
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作者 Mi Yang Hong-Yi Lan +2 位作者 Hong Wu Xu Wang Xin-Ju Li 《Clinical Research Communications》 2024年第3期23-28,共6页
Background:“Yang Transforming Qi and Yin shaping”comes from“Plain Question Yin and Yang should be like the theory”.Chinese medicine believes that the imbalance of yin and yang is the cause of human diseases.One of... Background:“Yang Transforming Qi and Yin shaping”comes from“Plain Question Yin and Yang should be like the theory”.Chinese medicine believes that the imbalance of yin and yang is the cause of human diseases.One of the strengths of TCM in treating diseases is holistic regulation.The theory of“Yang transforming Qi,and Yin shaping”implies a strong holistic view.Chloasma,one of the common skin diseases,seriously affects the physical and mental health of patients due to its unclear etiology,difficult treatment and easy recurrence.The occurrence and development of chloasma are closely related to internal organs.This paper is based on the theory of internal meridian,“Yang transforming Qi,and Yin shaping”which attaches importance to the concept of“Yang Qi”,from a new understanding of the pathogenesis etiology of chloasma.Methods:The author believes that the incidence of the disease is the deficiency of Yang Qi,which can’t promote the movement of Qi and blood to nourish the face,resulting in tangible material condensation,so proposes that this disease needs to be promoted by Yang transforming Qi and warm to dissipate.Moxibustion belongs to the fire,and its warming effect can dissipate the tangible evil.Results:Combined with clinical practice and the theory of internal meridian,the author elaborated that moxibustion is one of the effective methods for treating chloasma,which provides a new way of thinking for the treatment of chloasma.Conclusion:“Yang Transforming Qi and Yin shaping”can be used to guide the treatment of chloasma. 展开更多
关键词 Yang Transforming Qi and Yin shaping MOXIBUSTION CHLOASMA
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BDD-DETR:高效感知小目标的锂电池表面缺陷检测
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作者 邢远秀 刘颛玮 +1 位作者 邢玉峰 王文波 《储能科学与技术》 北大核心 2025年第1期370-379,共10页
针对锂电池外壳端面缺陷尺度和形状差异大而导致小目标缺陷识别困难等问题,提出BDD-DETR(battery defects detection-detection transformer)的锂电池表面缺陷检测算法。BDD-DETR架构在通用的特征提取模块和检测头模块间融入全新的模块... 针对锂电池外壳端面缺陷尺度和形状差异大而导致小目标缺陷识别困难等问题,提出BDD-DETR(battery defects detection-detection transformer)的锂电池表面缺陷检测算法。BDD-DETR架构在通用的特征提取模块和检测头模块间融入全新的模块特征感知与融合网络,通过自适应特征感知模块和特征融合路径从多个方向融合网络的深层与浅层特征,增强关键特征信息响应并抑制冗余特征,进一步提升模型多尺度特征融合能力和小目标感知能力;此外,为了减小缺陷边界框回归时的距离偏差和形状偏差,采用Shape IoU(shape intersection over union)损失函数训练网络模型。实验结果表明,在构建的锂电池端面缺陷数据集上,与CoDETR(collaborative-detection transformer)比较,BDD-DETR平均精度提升了3.7%,小尺度目标检测精度提升了8.9%,平均召回率提升了1.1%,在锂电池的小目标缺陷检测性能上优于目前一些先进的目标检测方法。 展开更多
关键词 锂离子电池 缺陷检测 Co-DETR 特征感知与融合网络 Shape IoU损失
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乡村旅游项目投资收益如何分配更有激励性?——基于浙江省湖州市DY村旅游项目投资开发的实证分析
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作者 沈国琪 《旅游研究》 2025年第4期31-44,共14页
乡村旅游开发收益分配时不能仅仅考虑各方的资源投入的多少,同时还应考虑投入的有效性、各方风险分担、合作中各自计划任务完成进度等因素。本研究以浙江省湖州市DY村为例,基于参与主体各自的角色定位,运用合作博弈的Shapely值修正模型... 乡村旅游开发收益分配时不能仅仅考虑各方的资源投入的多少,同时还应考虑投入的有效性、各方风险分担、合作中各自计划任务完成进度等因素。本研究以浙江省湖州市DY村为例,基于参与主体各自的角色定位,运用合作博弈的Shapely值修正模型对乡村旅游开发收益分配问题进行分析,并引入资源投入有效性、开发环节风险承担比例、各方任务计划完成情况和额外增加的成本支出等4个因素对模型进行修正和优化。研究结果表明,修正后的Shapely值能够较好地反映乡村旅游项目投资开发中各方价值创造的实际情况,收益分配比例更合理,并且具有较好的现实意义和可操作性。研究结论可以为乡村旅游项目开发利益分配提供借鉴和参考,从而保障项目开发稳定有序推进。 展开更多
关键词 乡村旅游项目 利益分配 激励性 SHAPELY值
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基于Alpha Shapes轮廓点云识别算法的洞室表面形变区域提取方法 被引量:2
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作者 张雨婷 郑德华 李思远 《南京信息工程大学学报》 北大核心 2025年第2期181-190,共10页
针对三维激光扫描密集点云提取洞室表面变形信息的问题,本文提出一种基于改进的Alpha Shapes算法识别洞室轮廓点云和多尺度模型到模型的点云比对(Multiscale Model-to-Model Cloud Comparison,M3C2)的洞室表面变形监测方法.首先对获取... 针对三维激光扫描密集点云提取洞室表面变形信息的问题,本文提出一种基于改进的Alpha Shapes算法识别洞室轮廓点云和多尺度模型到模型的点云比对(Multiscale Model-to-Model Cloud Comparison,M3C2)的洞室表面变形监测方法.首先对获取到的两期洞室表面点云数据进行配准,采用改进的Alpha Shapes算法识别洞室表面外轮廓点云.获得的两期洞室表面外轮廓点云经精配准后,再采用M3C2算法进行各点变形值计算,最后进行距离聚类提取连续形变区域.实验结果表明:该方法能够有效剔除点云中细小沟壑处的点及受到混合像元影响的点,在洞室截面到扫描仪距离10 m的范围内,两期点云剔除率分别为14.17%及13.52%,在70 m范围内,分别为6.25%及6.42%;该方法能够准确高效地提取出2倍配准误差以上的洞室表面形变区域. 展开更多
关键词 洞室变形监测 轮廓点云识别 Alpha Shapes算法 M3C2算法
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Multiple Kalman filters model with shaping filter GPS real-time deformation analysis 被引量:6
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作者 李丽华 彭军还 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3674-3681,共8页
In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GP... In order to detect the deformation in real-time of the GPS time series and improve its reliability, the multiple Kalman filters model with shaping filter was proposed. Two problems were solved: firstly, because the GPS real-time deformation series with a high sampling rate contain coloured noise, the multiple Kalman filter model requires the white noise, and the multiple Kalman filters model is augmented by a shaping filter in order to reduce the colored noise; secondly, the multiple Kalman filters model with shaping filter can detect the deformation epoch in real-time and improve the quality of GPS measurements for the real-time deformation applications. Based on the comparisons of the applications in different GPS time series with different models, the advantages of the proposed model were illustrated. The proposed model can reduce the colored noise, detect the smaller changes, and improve the precision of the detected deformation epoch. 展开更多
关键词 multiple Kalman filters model Kalman filter shaping filter deformation detection
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碱性条件下yybP核糖开关结合Mn^(2+)的构象分析
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作者 于莹莹 冯姗姗 +3 位作者 肖雯雯 陈婷 张云龙 陆昌瑞 《生物学杂志》 北大核心 2025年第3期9-14,共6页
yybP-ykoY家族是细菌中常见的核糖开关类型,对Mn^(2+)浓度具有高度敏感的监测能力。在大肠杆菌alx基因5′-UTR区含有一个包含yybP核糖开关保守序列的pH响应元件。根据结构预测,其与已知在乳酸乳球菌中位于yoaB基因上游的核糖开关结构类... yybP-ykoY家族是细菌中常见的核糖开关类型,对Mn^(2+)浓度具有高度敏感的监测能力。在大肠杆菌alx基因5′-UTR区含有一个包含yybP核糖开关保守序列的pH响应元件。根据结构预测,其与已知在乳酸乳球菌中位于yoaB基因上游的核糖开关结构类似,推测Mn^(2+)结合位点可能也位于L1、L3环。然而,目前大肠杆菌yybP核糖开关适体域的研究集中在静态解析上,对其在不同pH条件下结合Mn^(2+)产生的构象变化尚不明确。通过运用SHAPE化学探测法对yybP核糖开关适体域在不同pH(pH 6.0、7.0和8.0)条件下与Mn^(2+)结合前后的构象差异进行分析。结果证实了Mn^(2+)结合位点位于L1和L3环处,并且在改变pH后,yybP核糖开关与Mn^(2+)仍能结合;此外,在pH 8.0条件下,yybP核糖开关的P1、P2整体核酸骨架折叠成紧凑的双螺旋结构。综上结果表明,yybP核糖开关在碱性条件下与Mn^(2+)结合后使其结构更加稳定,推测其有利于yybP核糖开关下游alx基因的调节,为后续研究该核糖开关的作用机制提供理论依据。 展开更多
关键词 yybP核糖开关 适体域 SHAPE化学探测法 Mn^(2+) pH
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