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Current Situations of Internet Based Transformation and Upgrade of Hubei Comfort International Travel Service Co.,Ltd.
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作者 Huimin MA Chengfeng YU 《Asian Agricultural Research》 2018年第10期27-29,共3页
In the era of " Internet + ",the " Internet + tourism" comes into being,bringing unlimited development space and more possibilities to the traditional travel agency industry. Under the dual influen... In the era of " Internet + ",the " Internet + tourism" comes into being,bringing unlimited development space and more possibilities to the traditional travel agency industry. Under the dual influence of development and impact,travel agencies start to take the road of transformation. Taking Hubei Comfort International Travel Service Co.,Ltd. as an example,this paper analyzed and evaluated the current situations of Internet based transformation and upgrade,and came up with some pertinent recommendations. 展开更多
关键词 旅游业 旅行社 经济发展 发展现状
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Upgrade and Optimization Scheme:GSM Intelligent Network to Destination Network
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作者 Guo Zhong Xu Kai(Jiangsu Branch of China United Telecommunications Corporation,Nanjing 210000,China) 《ZTE Communications》 2007年第4期50-54,共5页
The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than... The networking of intelligent networks involves overlay network and destination network.Destination network triggers intelligent services by the CAMEL Subscription Information(CSI),and it has broader applications than overlay network.Upgrade from existing network to destination network requires a multitude of preparations and tests.Cities and provinces upgrade their networks from the aspects of Service Control Point(SCP),Home Location Register(HLR),Mobile Switching Center(MSC),Gateway Mobile Switching Center(GMSC)and subsciption information through different processes.In order to fully realize the destination network after upgrading the accounting systems,the bill collection have to be rebuilt while the value-added services have to be upgraded.However,many difficulties,such as the Originating-CAMEL Subscription Information(O-CSI),the Terminating-CAMEL Subscription Information(T-CSI),and the special access number optimization,which all needs a particular solution,exist in upgrading. 展开更多
关键词 HLR MSC GSM upgrade and Optimization Scheme
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基于长短期记忆网络-Transformer模型参数优化的锂离子电池剩余使用寿命预测
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作者 高建树 郝世宇 党一诺 《汽车工程师》 2026年第1期32-39,共8页
为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transforme... 为提高锂离子电池剩余使用寿命(RUL)预测的准确性,提出了一种基于长短期记忆(LSTM)网络-Transformer模型参数优化的RUL预测方法,采用网格搜索法选取模型的超参数,利用LSTM网络提取锂离子电池时间序列中的长短期依赖关系,使用Transformer的自注意力机制处理全局信息并对超参数进行优化,通过全连接层进行最终的寿命预测。基于美国国家航空航天局(NASA)数据集和先进生命周期工程中心(CALCE)数据集的试验验证结果表明,模型在更短的序列长度、更少的隐藏层数量和训练次数等条件下,在多种评价指标上均优于LSTM网络模型、Transformer模型及其他神经网络模型,具有更高的预测精度和鲁棒性。最后,通过不同电池的对比试验进一步验证了模型在不同电池数据上的泛化能力。 展开更多
关键词 锂离子电池 剩余使用寿命预测 参数优化 长短期记忆神经网络 transformER 混合模型
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Power Transformer Fault Diagnosis Using Random Forest and Optimized Kernel Extreme Learning Machine 被引量:2
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作者 Tusongjiang Kari Zhiyang He +3 位作者 Aisikaer Rouzi Ziwei Zhang Xiaojing Ma Lin Du 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期691-705,共15页
Power transformer is one of the most crucial devices in power grid.It is significant to determine incipient faults of power transformers fast and accurately.Input features play critical roles in fault diagnosis accura... Power transformer is one of the most crucial devices in power grid.It is significant to determine incipient faults of power transformers fast and accurately.Input features play critical roles in fault diagnosis accuracy.In order to further improve the fault diagnosis performance of power trans-formers,a random forest feature selection method coupled with optimized kernel extreme learning machine is presented in this study.Firstly,the random forest feature selection approach is adopted to rank 42 related input features derived from gas concentration,gas ratio and energy-weighted dissolved gas analysis.Afterwards,a kernel extreme learning machine tuned by the Aquila optimization algorithm is implemented to adjust crucial parameters and select the optimal feature subsets.The diagnosis accuracy is used to assess the fault diagnosis capability of concerned feature subsets.Finally,the optimal feature subsets are applied to establish fault diagnosis model.According to the experimental results based on two public datasets and comparison with 5 conventional approaches,it can be seen that the average accuracy of the pro-posed method is up to 94.5%,which is superior to that of other conventional approaches.Fault diagnosis performances verify that the optimum feature subset obtained by the presented method can dramatically improve power transformers fault diagnosis accuracy. 展开更多
关键词 Power transformer fault diagnosis kernel extreme learning machine aquila optimization random forest
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Mechanism and Implementation Panths of Low-Altitude Economy in Promoting Transformation and Upgrading of Tourism Industry in Zhejiang Province
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作者 Zhenzi GUO 《Asian Agricultural Research》 2025年第8期13-15,26,共4页
Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds tha... Taking Zhejiang Province as an example,this paper explores the mechanisms and implementation pathways through which the low-altitude economy drives the transformation and upgrading of the tourism industry.It finds that the low-altitude economy can effectively promote the development of high-end and diversified tourism in Zhejiang by innovating tourism formats,optimizing resource allocation,and enhancing tourist experiences.Besides,it analyzes the current development status of the low-altitude economy in Zhejiang and its potential for integration with tourism,revealing specific enabling pathways for tourism transformation,including low-altitude sightseeing,aviation tourism,and low-altitude sports.Finally,it proposes policy recommendations such as strengthening policy support,enhancing infrastructure development,and cultivating market entities.The findings aim to provide theoretical references and practical guidance for the high-quality development of tourism in Zhejiang Province. 展开更多
关键词 LOW-ALTITUDE ECONOMY transformation and upgrading of the tourism industry Action MECHANISM IMPLEMENTATION path ZHEJIANG Province
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ESG rating and transformation upgrading of enterprises:An empirical test based on the heterogeneity of listed A-share enterprises
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作者 WEI Yu-xin LI Peng-yu +1 位作者 LI Yan CHEN Xi-meng 《Ecological Economy》 2025年第1期48-65,共18页
ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning ... ESG(Environmental,Social,and Governance)performance has emerged as a central metric in assessing corporate sustainability.Utilizing ESG rating data for A-share listed companies on the Shanghai Stock Exchange spanning from 2019 to 2022,coupled with measures of corporate transformation and upgrading,this study introduces green innovation as a mediating variable to dissect the impact of ESG ratings on corporate transformation and upgrading.The key findings of this research are as follows:(1)ESG ratings positively influence corporate transformation and upgrading,a conclusion that retains robustness after a comprehensive series of tests and discussions on endogeneity.(2)Mechanism analysis reveals that ESG ratings foster corporate transformation and upgrading by enhancing corporate green innovation.(3)In comparison with other industries,the influence of ESG ratings on corporate transformation and upgrading is notably more pronounced among heavily polluting industries among listed companies in China.Additionally,ESG ratings exhibit a more significant promotional effect on non-state-owned enterprises compared to state-owned enterprises.Larger enterprises play a more substantial role in transformation and upgrading than small and medium-sized enterprises.The promotional effect of ESG ratings is more evident in enterprises with poor information disclosure quality.Furthermore,as media attention increases,so does the impact of ESG ratings on corporate transformation.This study offers valuable policy insights from the ESG rating perspective,aiming to propel corporate transformation and upgrading,thereby contributing to economic high-quality and sustainable development. 展开更多
关键词 ESG rating enterprise transformation and upgrading heterogeneity analysis
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Rural Revitalization and the Transformation of Xinhui Chenpi Industry: A Case Study of Policy Implementation and Development Pathways
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作者 Yuxin Yang 《Proceedings of Business and Economic Studies》 2025年第5期132-141,共10页
This paper examines the transformation and development of the Xinhui Chenpi industry under the rural revitalization strategy in China.The study highlights the significant growth of the industry,with the annual product... This paper examines the transformation and development of the Xinhui Chenpi industry under the rural revitalization strategy in China.The study highlights the significant growth of the industry,with the annual production of chenpi reaching approximately 7,000 tons and the total output value surpassing 26 billion yuan in 2024.The paper proposes strategies to foster sustainable growth in industries facing challenges such as inefficient production processes,inconsistent product quality,and a lack of policy awareness among operators.These strategies include optimizing support policies,enhancing regulatory frameworks,and leveraging digital technologies for brand building and market expansion.The research contributes to understanding the development trajectory of the Xinhui Chenpi industry and provides insights for policymakers and industry practitioners. 展开更多
关键词 Rural revitalization Industrial transformation Policy optimization Digital marketing
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Research on the Impact of the Construction of Cross-border E-commerce Comprehensive Pilot Zones on China’s Export Transformation and Upgrading
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作者 Jiahui Zhao 《Proceedings of Business and Economic Studies》 2025年第6期45-52,共8页
Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown... Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown,the relatively small scale of cross-border e-commerce,a high concentration of export commodities,imperfect information mechanisms,and high overall costs.To address these challenges,this paper explores the importance of the construction of the Dalian comprehensive pilot zone for cross-border e-commerce to the transformation and upgrading of exports.Based on my research project,“Research on Path Optimization of Financial Support for the Development of Advanced Manufacturing Clusters in Dalian,”this paper analyzes the current challenges and limiting factors and proposes corresponding countermeasures and suggestions. 展开更多
关键词 Cross-border e-commerce comprehensive pilot zone Cross-border e-commerce Export transformation and upgrading Foreign trade export
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Analysis on the adjustment of transportation structure and the logistics transformation of railway freight
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作者 Chaohe Rong Xingchan Li +1 位作者 Gaiping Zhang Xuecheng Wang 《Railway Sciences》 2025年第1期82-96,共15页
Purpose–This paper aims to provide a comprehensive analysis of the strategic adjustments in China’s transportation structure,with a particular focus on the pivotal role of railway freight and its integration into th... Purpose–This paper aims to provide a comprehensive analysis of the strategic adjustments in China’s transportation structure,with a particular focus on the pivotal role of railway freight and its integration into the modern logistics system.It seeks to address the need for a more nuanced understanding of the“road to rail”policy,emphasizing the importance of intermodal collaboration and service of fragmented market demands.Design/methodology/approach–The study employs a transport economics perspective to evaluate the achievements and shortcomings of China’s transportation structure optimization.It bases its assessment of the current state of railway freight logistics,multi-modal transportation and the broader implications for the transportation service market on data analysis.The methodology includes a review of existing policies,an examination of industry practices and a comparative analysis with global trends in railway logistics.Findings–The research underscores the importance of focusing on the development of non-bulk materials,noting the insufficiency in the development of China’s rail multi-modal transportation and highlighting the instructive value of successful cases in open-top container road-rail intermodal transportation.The study posits that the railway sector must enhance cooperation with other market entities,aligning with the lead enterprises in the logistics chain that are characterized by speed,high value and strong coordination capabilities,in order to better serve the transportation market.This approach moves away from a reliance on the railway’s own capabilities alone.Originality/value–This paper offers original insights into the transformation of railway freight in China,contributing to the body of knowledge on transportation economics and logistics.It provides valuable recommendations for policymakers and industry practitioners,emphasizing the strategic importance of railway logistics in the context of China’s economic development and intense competition in the supply chain.The value of the article lies in its comprehensive understanding of the complexities involved in the adjustment of transportation structures,providing direction for the market-oriented reform of China’s railway freight sector. 展开更多
关键词 Transportation structure optimization Railway freight Logistics transformation Multi-modal transport
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Fast Parallel Magnetic Resonance Imaging Reconstruction Based on Sparsifying Transform Learning and Structured Low-Rank Model
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作者 DUAN Jizhong XU Yuhan HUANG Huan 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期499-509,共11页
The structured low-rank model for parallel magnetic resonance(MR)imaging can efficiently reconstruct MR images with limited auto-calibration signals.To improve the reconstruction quality of MR images,we integrate the ... The structured low-rank model for parallel magnetic resonance(MR)imaging can efficiently reconstruct MR images with limited auto-calibration signals.To improve the reconstruction quality of MR images,we integrate the joint sparsity and sparsifying transform learning(JTL)into the simultaneous auto-calibrating and k-space estimation(SAKE)structured low-rank model,named JTLSAKE.The alternate direction method of multipliers is exploited to solve the resulting optimization problem,and the optimized gradient method is used to improve the convergence speed.In addition,a graphics processing unit is used to accelerate the proposed algorithm.The experimental results on four in vivo human datasets demonstrate that the reconstruction quality of the proposed algorithm is comparable to that of JTL-based low-rank modeling of local k-space neighborhoods with parallel imaging(JTL-PLORAKS),and the proposed algorithm is 46 times faster than the JTL-PLORAKS,requiring only 4 s to reconstruct a 200×200 pixels MR image with 8 channels. 展开更多
关键词 structured low-rank parallel magnetic resonance imaging sparsifying transform learning alternating direction method of multipliers optimized gradient method
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Electrocardiogram Signal Denoising Using Optimized Adaptive Hybrid Filter with Empirical Wavelet Transform
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作者 BALASUBRAMANIAN S NARUKA Mahaveer Singh TEWARI Gaurav 《Journal of Shanghai Jiaotong university(Science)》 2025年第1期66-80,共15页
Cardiovascular diseases are the world’s leading cause of death;therefore cardiac health of the human heart has been a fascinating topic for decades.The electrocardiogram(ECG)signal is a comprehensive non-invasive met... Cardiovascular diseases are the world’s leading cause of death;therefore cardiac health of the human heart has been a fascinating topic for decades.The electrocardiogram(ECG)signal is a comprehensive non-invasive method for determining cardiac health.Various health practitioners use the ECG signal to ascertain critical information about the human heart.In this article,swarm intelligence approaches are used in the biomedical signal processing sector to enhance adaptive hybrid filters and empirical wavelet transforms(EWTs).At first,the white Gaussian noise is added to the input ECG signal and then applied to the EWT.The ECG signals are denoised by the proposed adaptive hybrid filter.The honey badge optimization(HBO)algorithm is utilized to optimize the EWT window function and adaptive hybrid filter weight parameters.The proposed approach is simulated by MATLAB 2018a using the MIT-BIH dataset with white Gaussian,electromyogram and electrode motion artifact noises.A comparison of the HBO approach with recursive least square-based adaptive filter,multichannel least means square,and discrete wavelet transform methods has been done in order to show the efficiency of the proposed adaptive hybrid filter.The experimental results show that the HBO approach supported by EWT and adaptive hybrid filter can be employed efficiently for cardiovascular signal denoising. 展开更多
关键词 electrocardiogram(ECG)signal denoising empirical wavelet transform(EWT) honey badge optimization(HBO) adaptive hybrid filter window function
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Estimating primaries by sparse inversion of the 3D Curvelet transform and the L1-norm constraint 被引量:7
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作者 冯飞 王德利 +1 位作者 朱恒 程浩 《Applied Geophysics》 SCIE CSCD 2013年第2期201-209,237,共10页
In this paper, we built upon the estimating primaries by sparse inversion (EPSI) method. We use the 3D curvelet transform and modify the EPSI method to the sparse inversion of the biconvex optimization and Ll-norm r... In this paper, we built upon the estimating primaries by sparse inversion (EPSI) method. We use the 3D curvelet transform and modify the EPSI method to the sparse inversion of the biconvex optimization and Ll-norm regularization, and use alternating optimization to directly estimate the primary reflection coefficients and source wavelet. The 3D curvelet transform is used as a sparseness constraint when inverting the primary reflection coefficients, which results in avoiding the prediction subtraction process in the surface-related multiples elimination (SRME) method. The proposed method not only reduces the damage to the effective waves but also improves the elimination of multiples. It is also a wave equation- based method for elimination of surface multiple reflections, which effectively removes surface multiples under complex submarine conditions. 展开更多
关键词 Sparse inversion primary reflection coefficients 3D Curvelet transformation L1regularization convex optimization
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The optimal fractional Gabor transform based on the adaptive window function and its application 被引量:4
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作者 陈颖频 彭真明 +2 位作者 贺振华 田琳 张洞君 《Applied Geophysics》 SCIE CSCD 2013年第3期305-313,358,共10页
We designed the window function of the optimal Gabor transform based on the time-frequency rotation property of the fractional Fourier transform. Thus, we obtained the adaptive optimal Gabor transform in the fractiona... We designed the window function of the optimal Gabor transform based on the time-frequency rotation property of the fractional Fourier transform. Thus, we obtained the adaptive optimal Gabor transform in the fractional domain and improved the time-frequency concentration of the Gabor transform. The algorithm first searches for the optimal rotation factor, then performs the p-th FrFT of the signal and, finally, performs time and frequency analysis of the FrFT result. Finally, the algorithm rotates the plane in the fractional domain back to the normal time-frequency plane. This promotes the application of FrFT in the field of high-resolution reservoir prediction. Additionally, we proposed an adaptive search method for the optimal rotation factor using the Parseval principle in the fractional domain, which simplifies the algorithm. We carried out spectrum decomposition of the seismic signal, which showed that the instantaneous frequency slices obtained by the proposed algorithm are superior to the ones obtained by the traditional Gabor transform. The adaptive time frequency analysis is of great significance to seismic signal processing. 展开更多
关键词 FrFT generalized time bandwidth product optimal rotation factor search adaptive optimal Gabor transform spectral decomposition seismic signals
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Intelligent Transformation and Upgrading of Oil Refining & Petrochemical Industries in China:Investigation & Application 被引量:2
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作者 Wu Qing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2019年第2期1-9,共9页
The oil refining and petrochemical industry in China has made great achievements after decades of development, and its capacity has already ranked second in the world. However, the refining industry is suffering some ... The oil refining and petrochemical industry in China has made great achievements after decades of development, and its capacity has already ranked second in the world. However, the refining industry is suffering some challenges, such as severe overcapacity at present, and has entered a new economic normal, in which the technological progress develops rapidly, the demand for green and low-carbon development is stricter, the market competition is increasingly fiercer and the profit margins are gradually narrowing. In such a situation, informatization and its new technologies are driving the significant reforming of manufacturing patterns, marketing patterns, management and decision-making patterns. Intelligent development is the inevitable choice for the transformation and upgrading of oil refining and petrochemical industry. It is suggested that the intelligent evaluating model and method should be adopted to enterprise’s intelligentializing transformation and upgrading by laying a solid foundation of digital refinery and implemenation of digital upgrading. 展开更多
关键词 plant OIL OIL refining and petrochemical enterprise INTELLIGENT INFORMATIZATION DIAGNOSES model intelligentializing transformation and upgrading digital REFINERY INTELLIGENT REFINERY smart REFINERY
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Directional Filter for SAR Images Based on Nonsubsampled Contourlet Transform and Immune Clonal Selection 被引量:3
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作者 Xiao-Hui Yang Li-Cheng Jiao Deng-Feng Li 《International Journal of Automation and computing》 EI 2009年第3期245-253,共9页
A directional filter algorithm for intensity synthetic aperture radar (SAR) image based on nonsubsampled contourlet transform (NSCT) and immune clonal selection (ICS) is presented. The proposed filter mainly foc... A directional filter algorithm for intensity synthetic aperture radar (SAR) image based on nonsubsampled contourlet transform (NSCT) and immune clonal selection (ICS) is presented. The proposed filter mainly focuses on exploiting different features of edges and noises by NSCT. Furthermore, ICS strategy is introduced to optimize threshold parameter and amplify parameter adaptively. Numerical experiments on real SAR images show that there are improvements in both visual effects and objective indexes. 展开更多
关键词 Directional filter nonsubsampled contourlet transform (NSCT) immune clonal selection optimization (ICSO) syntheticaperture radar (SAR).
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Open Park Transformation and Upgrading Means of Comprehensive Park: A Case Study of Xuzhou Quanshan Forest Park 被引量:1
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作者 CHENG Yuwei 《Journal of Landscape Research》 2016年第5期119-122,共4页
The transformation and upgrading of comprehensive park can not be only limited to the adjustment for structure, function and landscape facility of comprehensive park itself, which shall be carried out as a whole. View... The transformation and upgrading of comprehensive park can not be only limited to the adjustment for structure, function and landscape facility of comprehensive park itself, which shall be carried out as a whole. Viewing from the macroscopic perspective of city, comprehensive park is an important constituent part of urban green space system, and its transformation is an integral part of overall perfection and development of urban green space system. Park is an organic integrity comprising many elements. The transformation of comprehensive park shall be carried out as a whole and handled by using the methods of "from top to bottom" and "from bottom to top", thus adjusting the relationship between park and city and within park on the whole. This research takes the open park transformation and upgrading of Xuzhou Quanshan Forest Park as an example to introduce the key points of open park transformation from such aspects as of entrance space, overall space structure, service function expansion and spatial form optimization in expectation of having a certain reference value. 展开更多
关键词 Comprehensive park Open park transformation UPGRADING
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结合MoE与Transformer的生态翻译模型优化研究
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作者 李玲 雷宏友 《自动化与仪器仪表》 2025年第4期178-181,186,共5页
生态翻译过程是译者进行适应与选择的过程,翻译原则是多维度的选择性适应以及适应性选择。虽然目前Transformer模型在生态翻译领域取得了显著的成果,然而在面对生态翻译中的复杂语义和多模态信息时,Transformer模型仍存在容量瓶颈和破... 生态翻译过程是译者进行适应与选择的过程,翻译原则是多维度的选择性适应以及适应性选择。虽然目前Transformer模型在生态翻译领域取得了显著的成果,然而在面对生态翻译中的复杂语义和多模态信息时,Transformer模型仍存在容量瓶颈和破坏模块化结构的问题。为此,研究提出结合专家混合与Transformer的生态翻译模型优化方法,通过引入专家混合机制,旨在提升模型对多样化输入的处理能力与翻译质量。研究结果表明,在Europarl数据集上,所提模型的翻译准确率总体保持在94%以上;在ParaCrawl数据集中,所提模型的准确率同样稳定在95%以上,且具有较强的稳定性,验证了此次研究的有效性。此次研究为生态翻译模型的优化提供了更广阔的思路和经验指导。 展开更多
关键词 生态翻译模型 transformER 专家混合 模型优化 神经机器翻译
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A Novel Hybrid Pan-Sharpen Method Using IHS Transform and Optimization 被引量:1
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作者 Haiyong Ding Wenzhong Shi 《Advances in Remote Sensing》 2017年第3期229-243,共15页
Intensity-hue-saturation (IHS) transform is the most commonly used method for image fusion purpose. Usually, the intensity image is replaced by Panchromatic (PAN) image, or the difference between PAN and intensity ima... Intensity-hue-saturation (IHS) transform is the most commonly used method for image fusion purpose. Usually, the intensity image is replaced by Panchromatic (PAN) image, or the difference between PAN and intensity image is added to each bands of RGB images. Spatial structure information in the PAN image can be effectively injected into the fused multi-spectral (MS) images using IHS method. However, spectral distortion has become the typical factor deteriorating the quality of fused results. A hybrid image fusion method which integrates IHS and minimum mean-square-error (MMSE) was proposed to mitigate the spectral distortion phenomenon in this study. Firstly, IHS transform was used to derive the intensity image;secondly, the MMSE algorithm was used to fuse the histogram matched PAN image and intensity image;thirdly, optimization calculation was employed to derive the combination coefficients, and the new intensity image could be expressed as the combination of intensity image and PAN image. Fused MS images with high spatial resolution can be generated by inverse IHS transform. In numerical experiments, QuickBird images were used to evaluate the performance of the proposed algorithm. It was found that the spatial resolution was increased significantly;meanwhile, spectral distortion phenomenon was abated in the fusion results. 展开更多
关键词 IHS transform Pan-Sharpen Minimum Mean-Square-Error SPECTRAL DISTORTION Optimization Calculation
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基于改进时间融合Transformers的中国大豆需求预测方法
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作者 刘佳佳 秦晓婧 +5 位作者 李乾川 许世卫 赵继春 王一罡 熊露 梁晓贺 《智慧农业(中英文)》 2025年第4期187-199,共13页
[目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方... [目的/意义]精准预测大豆需求对保障国家粮食安全、优化产业决策与应对国际贸易变局有着重要的现实意义,而利用时间融合Transformers(Temporal Fusion Transformers,TFT)模型开展中国大豆需求预测时,在特征交互层与注意力权重分配等方面仍存在一定局限。为此,亟需探索一种基于改进TFT模型的预测方法,以提升需求预测的准确性与可解释性。[方法]本研究将深度学习的TFT模型应用到中国大豆需求预测中,提出了一种基于多层动态特征交互(Multi-layer Dynamic Feature Interaction,MDFI)与自适应注意力权重优化(Adaptive Attention Weight Optimization,AAWO)改进的MA-TFT(Improved TFT Model Based on MDFI and AAWO)模型。对包含1980—2024年4652个相关指标的中国大豆需求分析数据集进行数据预处理和特征工程,设计实验将MA-TFT模型分别与自回归差分移动平均模型(Autoregressive Integrated Moving Average Model,ARIMA)、长短期记忆网络(Long Short-Term Memory,LSTM)模型及TFT模型进行预测性能对比,进行了消融实验,同时利用SHAP(SHapley Additive exPlanations)工具可解释性分析影响中国大豆需求的关键特征变量,开展了未来10年的中国大豆需求量预测。[结果和讨论]MA-TFT模型的均方误差(Mean Squared Error,MSE)、平均绝对百分比误差(Mean Absolute Percentage Error,MAPE)分别为0.036和5.89%,决定系数R^(2)为0.91,均高于对比模型,均方根误差(Root Mean Square Error,RMSE)和MAPE分别较基准模型TFT累计降低21.84%和3.44%,表明改进TFT的MA-TFT模型能够捕捉特征间复杂关系,提升预测性能;研究利用SHAP工具可解释性分析发现,MA-TFT模型对影响中国大豆需求关键特征变量的解释稳定性较高;预计2025、2030和2034年中国大豆需求量分别达到11799万吨、11033万吨和11378万吨。[结论]基于改进TFT的MA-TFT模型方法为解决现有大豆需求预测方法精度不足、可解释性不强的实际问题提供了解决思路,也为其他农产品时间序列预测的方法优化与应用提供了参考和借鉴。 展开更多
关键词 时间融合transformers(TFT) 大豆需求预测 多层动态特征交互 自适应注意力权重优化 可解释性分析
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Lie Symmetry Analysis,Bcklund Transformations and Exact Solutions to (2+1)-Dimensional Burgers' Types of Equations 被引量:1
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作者 刘汉泽 李继彬 刘磊 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第5期737-742,共6页
This paper is concerned with the (2+1)-dimensional Burgers' and heat types of equations.All of the geometic vector fields of the equations are obtained,an optimal system of the equation is presented.Especially,the... This paper is concerned with the (2+1)-dimensional Burgers' and heat types of equations.All of the geometic vector fields of the equations are obtained,an optimal system of the equation is presented.Especially,the Bcklund transformations (BTs) for the Burgers' equations are constructed based on the symmetry.Then,all of the symmetry reductions are provided in terms of the optimal system method,and the exact explicit solutions are investigated by the symmetry reductions and Bcklund transformations. 展开更多
关键词 (2+1)-dimensional Burgers' equation heat equation Lie symmetry analysis Bcklund transformation optimal system exact solution
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