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Optimized Feature Selection for Leukemia Diagnosis Using Frog-Snake Optimization and Deep Learning Integration
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作者 Reza Goodarzi Ali Jalali +2 位作者 Omid Hashemi Pour Tafreshi Jalil Mazloum Peyman Beygi 《Computers, Materials & Continua》 2025年第7期653-679,共27页
Acute lymphoblastic leukemia(ALL)is characterized by overgrowth of immature lymphoid cells in the bone marrow at the expense of normal hematopoiesis.One of the most prioritized tasks is the early and correct diagnosis... Acute lymphoblastic leukemia(ALL)is characterized by overgrowth of immature lymphoid cells in the bone marrow at the expense of normal hematopoiesis.One of the most prioritized tasks is the early and correct diagnosis of this malignancy;however,manual observation of the blood smear is very time-consuming and requires labor and expertise.Transfer learning in deep neural networks is of growing importance to intricate medical tasks such as medical imaging.Our work proposes an application of a novel ensemble architecture that puts together Vision Transformer and EfficientNetV2.This approach fuses deep and spatial features to optimize discriminative power by selecting features accurately,reducing redundancy,and promoting sparsity.Besides the architecture of the ensemble,the advanced feature selection is performed by the Frog-Snake Prey-Predation Relationship Optimization(FSRO)algorithm.FSRO prioritizes the most relevant features while dynamically reducing redundant and noisy data,hence improving the efficiency and accuracy of the classification model.We have compared our method for feature selection against state-of-the-art techniques and recorded an accuracy of 94.88%,a recall of 94.38%,a precision of 96.18%,and an F1-score of 95.63%.These figures are therefore better than the classical methods for deep learning.Though our dataset,collected from four different hospitals,is non-standard and heterogeneous,making the analysis more challenging,although computationally expensive,our approach proves diagnostically superior in cancer detection.Source codes and datasets are available on GitHub. 展开更多
关键词 Acute lymphocyte leukemia feature fusion deep learning feature selection frog-snake prey-predation relationship optimization
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Predicting Academic Performance Levels in Higher Education:A Data-Driven Enhanced Fruit Fly Optimizer Kernel Extreme Learning Machine Model
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作者 Zhengfei Ye Yongli Yang +1 位作者 Yi Chen Huiling Chen 《Journal of Bionic Engineering》 2025年第4期1940-1962,共23页
Teacher–student relationships play a vital role in improving college students’academic performance and the quality of higher education.However,empirical studies with substantial data-driven insights remain limited.T... Teacher–student relationships play a vital role in improving college students’academic performance and the quality of higher education.However,empirical studies with substantial data-driven insights remain limited.To address this gap,this study collected 3278 questionnaires from seven universities across four provinces in China to analyze the key factors affecting college students’academic performance.A machine learning framework,CQFOA-KELM,was developed by enhancing the Fruit Fly Optimization Algorithm(FOA)with Covariance Matrix Adaptation Evolution Strategy(CMAES)and Quadratic Approximation(QA).CQFOA significantly improved population diversity and was validated on the IEEE CEC2017 benchmark functions.The CQFOA-KELM model achieved an accuracy of 98.15%and a sensitivity of 98.53%in predicting college students’academic performance.Additionally,it effectively identified the key factors influencing academic performance through the feature selection process. 展开更多
关键词 Academic achievement Machine learning Teacher-student relationships Swarm intelligence algorithms Fruit fly optimization algorithm
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Optimization of ISSR-PCR Reaction System and Preliminary Construction of ISSR Fingerprinting of Some Species in Bryaceae 被引量:3
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作者 汪琛颖 赵建成 《Agricultural Science & Technology》 CAS 2011年第11期1561-1564,1568,共5页
[Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats (ISSR) fingerprinting. [Method] In order to seek ... [Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats (ISSR) fingerprinting. [Method] In order to seek standardizing PCR reaction set-up, an orthogonal design was used to optimize ISSR-PCR amplification system of Bryaceae in five factors (Mg2+, dNTPs, primer, DNA template, Taq DNA polymerase) at four levels respectively. [Result] A suitable ISSR reaction system was obtained, namely: 20 μl reaction system containing 5 ng of DNA template, 0.2 μmol/L primer, 2.25 mmol/L MgCl2, 0.6 U of Taq DNA polymerase, 0.4 mmol/L dNTPs. Proper annealing temperature was found at 48-50 ℃.The above system and six ISSR-PCR primers were used for the PCR amplification of 14 samples from Bryaceae and the related species in Mniaceae. A total of 86 bands were amplified, all showed polymorphism. NJ cluster analysis showed a star-shaped cladogram. [Conclusion] The results manifested that ISSR fingerprinting could provide the appropriate degree of polymorphism at low taxonomic level, so it would be a useful tool to provide additional evidence for resolving taxonomic relationships at the species level of Bryaceae. 展开更多
关键词 BRYACEAE ISSR optimization of reaction system Species-level Taxonomic relationship
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Selective laser melting of magnesium alloys: Necessity, formability, performance, optimization and applications 被引量:18
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作者 Kun Li Chen Ji +2 位作者 Shengwen Bai Bin Jiang Fusheng Pan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第23期65-93,共29页
Selective laser melting (SLM), as a rapid prototyping technology, has been widely used to manufacture high-performance metal components with complex structures, which vitally provides a broad platform for the developm... Selective laser melting (SLM), as a rapid prototyping technology, has been widely used to manufacture high-performance metal components with complex structures, which vitally provides a broad platform for the development and application of magnesium alloys. However, the poor laser formability of magnesium alloys has deleterious consequences in the application of SLM processing. This paper discusses the defect formation mechanisms during the SLM process and summarizes characteristics in terms of mechanical properties, oxidation and corrosion resistance. Current optimization schemes are reviewed from both macro and micro perspectives. Firstly, the relationship between process parameters and formability and material properties is clarified, and advanced optimization methods of the design of experiments, physical models, and machine learning are evaluated. Secondly, the effects of alloying elements, composite reinforcement, and post-treatment on the microstructure and properties of the SLMed magnesium alloy are reviewed. Finally, the future application development prospects are envisaged based on the comprehensive review. This work is significantly helpful to a better scientific understanding of SLMed magnesium alloy and puts forward some meaningful guiding opinions for the future work of magnesium alloy manufacturing. 展开更多
关键词 Magnesium alloys Selective laser melting DEFECTS Microstructure-property relationship Performance optimization
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Optimization of evidence-based research in the prevention and treatment of coronary heart disease with traditional Chinese medicine:A comprehensive review 被引量:7
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作者 Hongcai Shang Kaige Zhang +1 位作者 Zhiyue Guan Xiaoyu Zhang 《Journal of Traditional Chinese Medical Sciences》 2022年第2期100-107,共8页
Coronary heart disease(CHD) has severely impacted the lives and health of patients for ages. Although the modern methods used for the prevention and treatment of CHD have been increasingly perfected,clinical problems ... Coronary heart disease(CHD) has severely impacted the lives and health of patients for ages. Although the modern methods used for the prevention and treatment of CHD have been increasingly perfected,clinical problems remain that require solutions. In the prevention and treatment of CHD with traditional Chinese medicine(TCM), great therapeutic advantages have been demonstrated. However, the expression of its advantages relies on scientific evidence-based research and evaluation, which require further optimization and improvement. Therefore, this review aims to comprehensively emphasize our understanding of the current deficiencies in TCM evidence-based studies and the necessity of adopting scientific evidence-based optimization methods for use in research. In this process, evidence should be produced in a standard manner, and the advantages of TCM patterns should be accurately stated because these factors contribute to efficient transformation and proper verification of the obtained evidence.Additionally, focusing on patient-oriented medicine and doctor-patient relationships is also essential.These methods are of great significance to prove the clinical efficacy of TCM and promote its development. 展开更多
关键词 Coronary heart disease Traditional Chinese medicine Evidence-based research Evidence-based medicine Patient-oriented medicine Doctorepatient relationships optimization
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Relationships among hamstring muscle optimal length and hamstring flexibility and strength 被引量:6
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作者 Xianglin Wan Feng Qu +2 位作者 William E.Garrett Hui Liu Bing Yu 《Journal of Sport and Health Science》 SCIE 2017年第3期275-282,共8页
Background:Hamstring muscle strain injury(hamstring injury) due to excessive muscle strain is one of the most common injuries in sports.The relationships among hamstring muscle optimal lengths and hamstring flexibilit... Background:Hamstring muscle strain injury(hamstring injury) due to excessive muscle strain is one of the most common injuries in sports.The relationships among hamstring muscle optimal lengths and hamstring flexibility and strength were unknown,which limited our understanding of risk factors for hamstring injury.This study was aimed at examining the relationships among hamstring muscle optimal length and flexibility and strength.Methods:Hamstring flexibility and isokinetic strength data and three-dimensional kinematic data for hamstring isokinetic tests were collected for11 male and 10 female recreational athletes.The maximal hamstring muscle forces,optimal lengths,and muscle lengths in standing were determined for each participant.Results:Hamstring muscle optimal lengths were significantly correlated to hamstring flexibility score and gender,but not to hamstring strength.The greater the flexibility score,the longer the hamstring muscle optimal length.With the same flexibility score,females tend to have shorter hamstring optimal muscle lengths compared to males.Hamstring flexibility score and hamstring strength were not correlated.Hamstring muscle optimal lengths were longer than but not significantly correlated to corresponding hamstring muscle lengths in standing.Conclusion:Hamstring flexibility may affect hamstring muscle maximum strain in movements.With similar hamstring flexibility,hamstring muscle maximal strain in a given movement may be different between genders.Hamstring muscle lengths in standing should not be used as an approximation of their optimal lengths in calculation of hamstring muscle strain in musculoskeletal system modeling. 展开更多
关键词 Injury risk factor Muscle biomechanics Muscle length–tension relationship Muscle optimal length Muscle strain Muscle strain injury
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Research on the Optimal Vegetation Cover for Remote Sensing Assessment of Soil Erosion Risk Using the Temporal Matching Relationship between Rainfall and Vegetation 被引量:1
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作者 Jianfeng Liu Xiwang Zhang 《Journal of Geoscience and Environment Protection》 2019年第2期22-36,共15页
Vegetation cover derived from remote sensing image is widely used for soil erosion risk assessment, but there is no clear guideline to select the most appropriate temporal satellite data. It is common practice that sa... Vegetation cover derived from remote sensing image is widely used for soil erosion risk assessment, but there is no clear guideline to select the most appropriate temporal satellite data. It is common practice that satellite data during growing season are randomly selected and used in soil erosion risk assessment. However, the effectiveness of vegetation in protecting the soil is quite different even if it is the same growing season since vegetation covers change as they grow. This article aims to provide a method of choosing optimal vegetation cover for studying soil erosion risk using remote sensing, that is, the vegetation cover in the most appropriate temporal period. Based on the temporal relationship of the two most active impact factors, rainfall and vegetation, an index of RV is developed and used to indicate the relative erosion risk during the year. The results show that annual variation of rainfall is significant, and vegetation is relatively stable, resulting in their matching relationship is different in each year. The correlation coefficient reaches 0.89 between RV and real sediment transport during the period when rainfall can cause soil erosion. In other words, RV is a good indicator of soil erosion. Therefore, there is a good correlation between RV maximum and the optimal vegetation cover, which can help facilitate erosion research in the future, showing good potential for successful application in other places. 展开更多
关键词 optimAL VEGETATION COVER Remote Sensing SOIL Erosion Risk TEMPORAL Matching relationship
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Evaluation on Radar Reflectivity-Rainfall Rate (Z-R) Relationships for Guyana 被引量:3
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作者 Komalchand Dhiram Zhenhui Wang 《Atmospheric and Climate Sciences》 2016年第4期489-499,共12页
The constant development of science and technology in weather radar results in high-resolution spatial and temporal rainfall estimates and improved early warnings of meteorological phenomena such as flood [1]. Weather... The constant development of science and technology in weather radar results in high-resolution spatial and temporal rainfall estimates and improved early warnings of meteorological phenomena such as flood [1]. Weather radars do not measure the rainfall amount directly, so a relationship between the reflectivity (Z) and rainfall rate (R), called the Z-R relationship (Z = aR<sup>b</sup>), where a and b are empirical constants, can be used to estimate the rainfall amount. In this research, mathematical techniques were used to find the best climatological Z-R relationships for the Low Coastal Plain of Guyana. The reflectivity data from the S-Band Doppler Weather Radar for February 17 and 21, 2011 and May 8, 2012 together with the daily rainfall depths at 29 rainfall stations located within a 150 km radius were investigated. A climatological Z-R relationship type Z = 200R<sup>1.6</sup> (Marshall-Palmer) configured by default into the radar system was used to investigate the correlation between the radar reflectivity and the rainfall by gauges. The same data sets were used with two distinct experimental Z-R relationships, Z = 300R<sup>1.4</sup> (WSR-88D Convective) and Z = 250R<sup>1.2</sup> (Rosenfeld Tropical) to determine if any could be applicable for area of study. By comprehensive regression analysis, New Z-R and R-Z relationships for each of the three events aforementioned were developed. In addition, a combination of all the samples for all three events were used to produce another relationship called “All in One”. Statistical measures were then applied to detect BIAS and Error STD in order to produce more evidence-based results. It is proven that different Z-R relationships could be calibrated into the radar system to provide more accurate rainfall estimation. 展开更多
关键词 Radar Reflectivity Rain Gauges Rainfall Rate z-r relationships CORRELATION
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Understanding the Variability of Z-R Relationships Caused by Natural Variations in Raindrop Size Distributions(DSD):Implication of Drop Size and Number 被引量:1
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作者 Abe D.Ochou Eric-Pascal Zahiri +1 位作者 Bakary Bamba Manlandon Koffi 《Atmospheric and Climate Sciences》 2011年第3期147-164,共18页
In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, se... In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, several pre-vious studies have shown the great variability of this relationship in space and time, from a rainfall event to another and even within a single rainfall event. Recent studies have shown that the variability of raindrop size distributions and thereby Z-R relationships is therefore, more the result of complex dynamic, thermody-namic and microphysical processes within rainfall systems than a convective/stratiform classification of the ground rainfall signature. The raindrop number and size at ground being the resultant of various processes mentioned above, a suitable approach would be to analyze their variability in relation to that of Z-R relation-ship. In this study, we investigated the total raindrop concentration number NT and the median volume di-ameter D0 used in numerous studies, and have shown that the combination of these two ‘observed’ parame-ters appears to be an interesting approach to better understand the variability of the Z-R relationships in the rainfall events, without assuming a certain analytical raindrop size distribution model (exponential, gamma, or log-normal). The present study is based on the analysis of disdrometer data collected at different seasons and places in Africa, and aims to show the degree of the raindrop size and number implication in regard to the Z-R relationships variability. 展开更多
关键词 Raindrop Size Distribution Radar Reflectivity Factor Rain Rate Median Volume Diameter Total Number of Drops Per Unit Volume z-r relationship Convective Rain Stratiform Rain Squall Lines THUNDERSTORM
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“City-Scene” Characteristics and Optimization Strategies Research on Three Gorges Reservoir Area of the Post-Three Gorges Era
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作者 LIAO Congquan LUO Ping 《Journal of Landscape Research》 2017年第1期8-14,共7页
In the long-term symbiotic evolution process,the town areas along the Yangtze River and its natural and cultural landscapes have presented a sound "city-scene" landscape form. But with the implementation of ... In the long-term symbiotic evolution process,the town areas along the Yangtze River and its natural and cultural landscapes have presented a sound "city-scene" landscape form. But with the implementation of the Three Gorges project,the town relocation as well as the flooding in the natural and human landscape area,the original harmonious "city-scene" pattern started to collapse and fell into the situation of "fragmentation" and "islanding". The differentiation between city and landscape,uncoordinated scale and fractured urban context become pressing issues that affect the integral form optimization of the town areas. This paper aims at responding to the call of the government about proceeding the construction of the Yangtze River economic belt under the ecological and green strategy and seeking an attuned "cityscene" relationship of the town area. Based on the analysis of the dynamic evolution of the "city-scene" relationship,the paper also pointed out that the urban construction around the reservoir area in the postThree Gorges era was the key stage of "scene-city" integration and symbiosis while the maintenance of scenery pattern,the harmony of space scale and the protection of living culture should be applied as the vital strategies. 展开更多
关键词 Town areas of the Three Gorges Reservoir City-scene relationship Cultural landscape Town form optimization
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The hit-to-lead optimization of 1,2,3,4,4a,9a-hexahydro-1H-xanthenes as glucocorticoid receptor antagonists
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作者 Yan-Hui Zhu Meng Zhang +5 位作者 Qun-Yi Li Qing Liu Jie Zhang Yun-Yun Yuan Fa-Jun Nan Ming-Wei Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期693-698,共6页
The structure–activity relationship(SAR) study of a 1 2 3 4 4a 9a-hexahydro-1H-xanthene series of selective,human glucocorticoid receptor a(hGRa) antagonists is reported.Compounds were screened using hydroxyapati... The structure–activity relationship(SAR) study of a 1 2 3 4 4a 9a-hexahydro-1H-xanthene series of selective,human glucocorticoid receptor a(hGRa) antagonists is reported.Compounds were screened using hydroxyapatite-based GR binding and MMTV-Luc co-transfection reporter gene assays.Four different regions of the scaffold were modified to assess the effects on hGRa antagonism and related potency.Compound 8d exhibits an 8-fold better bioactivity than the original hit 1a,as well as an improved chemical stability,which make it a promising lead for the subsequent optimization. 展开更多
关键词 Glucocorticoid receptor Antagonist 1 2 3 4 4a 9a-Hexahydroxanthene Structure–activity relationship Lead optimization
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Electric vehicle optimal scheduling method considering charging piles matching based on edge intelligence
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作者 Ning Guo Tuo Ji +5 位作者 Xiaolong Xiao Tiankui Sun Jinming Chen Xiaoxing Lu Xinyi Zheng Shufeng Dong 《iEnergy》 2024年第3期152-161,共10页
To adress the problems of insufficient consideration of charging pile resource limitations,discrete-time scheduling methods that do not meet the actual demand and insufficient descriptions of peak-shaving response cap... To adress the problems of insufficient consideration of charging pile resource limitations,discrete-time scheduling methods that do not meet the actual demand and insufficient descriptions of peak-shaving response capability in current electric vehicle(EV)opti-mization scheduling,edge intelligence-oriented electric vehicle optimization scheduling and charging station peak-shaving response capability assessment methods are proposed on the basis of the consideration of electric vehicle and charging pile matching.First,an edge-intelligence-oriented electric vehicle regulation frame for charging stations is proposed.Second,continuous time variables are used to represent the available charging periods,establish the charging station controllable EV load model and the future available charging pile mathematical model,and establish the EV and charging pile matching matrix and constraints.Then,with the goal of maximizing the user charging demand and reducing the charging cost,the charging station EV optimal scheduling model is established,and the EV peak response capacity assessment model is further established by considering the EV load shifting constraints under different peak response capacities.Finally,a typical scenario of a real charging station is taken as an example for the analysis of optimal EV scheduling and peak shaving response capacity,and the proposed method is compared with the traditional method to verify the effectiveness and practicality of the proposed method. 展开更多
关键词 Edge intelligence electric vehicle charging pile optimal scheduling matching relationship peak shaving responsiveness
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基于分量感知动态图Transformer的短期电力负荷预测 被引量:5
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作者 朱莉 高靖凯 +1 位作者 朱春强 邓凡 《计算机应用研究》 北大核心 2025年第2期381-390,共10页
准确的短期负荷预测对于电力系统的稳定运行和有效调度至关重要。电力负荷数据因存在非线性、非平稳性而导致预测精度低。分解可以降低序列非平稳性的影响从而有效地提高预测精度,但现有分解预测方法缺乏对分解分量间关系的捕获且显著... 准确的短期负荷预测对于电力系统的稳定运行和有效调度至关重要。电力负荷数据因存在非线性、非平稳性而导致预测精度低。分解可以降低序列非平稳性的影响从而有效地提高预测精度,但现有分解预测方法缺乏对分解分量间关系的捕获且显著增加了预测时间。为此,提出分量感知动态图Transformer(component-aware dynamic graph Transformer,CDGT)模型。首先,引入联合对立选择(joint opposite selection,JOS)算子和随机扰动改进雪消融优化算法(snow ablation optimizer,SAO),使用联合搜索和随机扰动的SAO(jointly searched and stochastic perturbed SAO,JSSAO)对变分模态分解(variational mode decomposition,VMD)进行参数寻优。VMD对原始的负荷数据进行分解得到不同频率的分量序列,然后使用图神经网络(graph neural network,GNN)来识别和建模分量之间的复杂关系。同时,使用引入频域指数滑动平均(exponential moving average,EMA)注意力的Transformer来学习分量内部的依赖关系。一次输出所有分量结果,线性相加后得到负荷预测值。通过两个公开负荷数据集的实验表明,CDGT优于一系列先进的基线以及分解预测方法,在澳大利亚数据集和摩洛哥数据集上,MAE分别降低了5.51%~31.08%和15.02%~75.49%。 展开更多
关键词 短期负荷预测 雪消融优化算法 变分模态分解 GNN关系建模 注意力机制
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窟野河流域人居环境空间特征及影响因素 被引量:2
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作者 张中华 吴昊 《风景园林》 北大核心 2025年第6期96-105,共10页
【目的】窟野河流域是黄河中游干旱半干旱地区的典型流域之一,在能源产业主导驱动的人居发展模式下,流域内水资源供应不足、水土流失严重、城水空间不协同、水资源污染等人水矛盾日益突出。拟从人水关系视角探讨窟野河流域人居环境与水... 【目的】窟野河流域是黄河中游干旱半干旱地区的典型流域之一,在能源产业主导驱动的人居发展模式下,流域内水资源供应不足、水土流失严重、城水空间不协同、水资源污染等人水矛盾日益突出。拟从人水关系视角探讨窟野河流域人居环境与水文环境的复杂关系,为流域人居环境与水文环境的和谐发展提供参考建议。【方法】以子流域(集水区)为研究单元,运用熵值法、SWAT水文模型、参数最优地理探测器等分析方法,揭示窟野河流域各子流域人居环境质量的空间特征,并从水文环境的规模、质量、形态等方面探测流域人居环境质量的影响因素。【结果】窟野河流域人居环境质量的空间分异特征为“局部核心集聚,沿主河道向四周扩散降低”。河网形态与发育程度是影响流域人居环境质量的核心因素,水资源的规模-质量-源汇的系统耦合关系是影响流域人居环境质量的主要因素,流域圆度率、流域长宽比是影响流域人居环境质量的次要因素,流域地形是影响流域人居环境质量的重要因素。【结论】1)窟野河流域人居环境质量存在显著的空间分异特征;2)流域人居环境质量是水文规模、水文形态、水文质量、流域地形等多因素长期耦合作用的结果;3)流域人居环境与水文环境存在复杂的相互作用关系,应基于人水关系和谐来提升优化流域人居环境质量。 展开更多
关键词 流域人居环境 人水关系 参数最优地理探测器 SWAT模型 影响因素
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社区托育服务合作供给中的多元主体关系困境与优化路径 被引量:1
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作者 毛明明 《牡丹江大学学报》 2025年第2期48-56,共9页
社区托育服务的合作供给已成为创新托育服务供给方式和构建高质量托育服务体系的有效举措。通过对社区托育服务合作供给中的多元主体进行划分,并对“四元主体”之间的关系样态进行检验发现,托育机构对地方政府的资源依赖、地方政府对托... 社区托育服务的合作供给已成为创新托育服务供给方式和构建高质量托育服务体系的有效举措。通过对社区托育服务合作供给中的多元主体进行划分,并对“四元主体”之间的关系样态进行检验发现,托育机构对地方政府的资源依赖、地方政府对托育机构的力量牵制、地方政府对基层社区的责任转移、基层社区对托育家庭的权威表达以及托育家庭对托育机构的行动抵牾正成为牵制社区托育服务有效供给的主要因素。为进一步提升社区托育服务的供给效率和供给品质,需要从明确托育主体权责边界,增进托育主体关系互信;调和托育主体利益关系,强化托育主体合作规范;提升托育机构专业水平,增强托育家庭服务认同;健全托育服务供给机制,完善托育主体行动秩序四个方面寻找社区托育服务合作供给中多元主体关系的优化路径。 展开更多
关键词 社区托育服务 合作供给 多元主体 关系困境 关系优化
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P2P交易随机博弈决策与复杂网络协同演化分析
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作者 张帅 裴玮 +3 位作者 蒲天骄 马腾飞 肖浩 王晓辉 《中国电机工程学报》 北大核心 2025年第S1期31-45,共15页
用户点对点(peer-to-peer,P2P)交易的兴起为推动终端产消者可再生能源的高效消纳提供了重要途径。然而,产消者之间交易行为的强不确定性及竞合关系的复杂性,严重制约P2P交易的进一步发展。此外,现有研究对交易网络长期演化规律的忽视也... 用户点对点(peer-to-peer,P2P)交易的兴起为推动终端产消者可再生能源的高效消纳提供了重要途径。然而,产消者之间交易行为的强不确定性及竞合关系的复杂性,严重制约P2P交易的进一步发展。此外,现有研究对交易网络长期演化规律的忽视也严重制约P2P交易相关政策的科学制定。为解决上述问题,该文提出一种P2P交易随机博弈决策与复杂网络协同演化分析方法,旨在系统优化交易策略并揭示交易网络的长期演化特性。首先,针对交易行为的不确定性,将随机博弈理论应用于P2P交易中,构建以产消者经济效益最大化为目标的动态交易模型,并通过基于供需比的价格机制确定最优交易价格。其次,通过随机博弈理论将产消者的多时段交易行为建模为Markov决策过程,实现多阶段动态策略调整,有效解决传统交易模型中对产消者交易行为中不确定性的忽略。之后,基于严谨的数学理论证明P2P交易中随机博弈Nash均衡的存在性,为随机博弈的实际应用奠定理论基础。随后,构建基于最佳阈值法和复杂网络理论的P2P交易网络,通过皮尔逊系数分析产消者间的竞合关系,并结合Fast Newman算法进行社群划分,揭示交易网络的动态结构演化规律。最后,通过算例仿真验证论文方法在优化产消者交易策略、提高经济效益以及分析交易网络长期演化规律中的有效性与可行性。 展开更多
关键词 点对点交易 随机博弈 复杂网络 协同演化 皮尔逊系数 最佳阈值法 竞合关系
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基于核化方法的多目标多任务优化算法
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作者 谭瑛 张瑞丽 +2 位作者 刘晓彤 孙超利 李春鹏 《太原科技大学学报》 2025年第3期201-207,共7页
近年来多任务优化受到了越来越多的关注,其主要思想是利用不同任务之间的知识迁移,从而促进不同任务的同时优化。然而,在知识迁移的过程中负迁移现象很难避免。为了尽可能避免负迁移,因此提出了一种基于核化方法的多目标多任务优化算法... 近年来多任务优化受到了越来越多的关注,其主要思想是利用不同任务之间的知识迁移,从而促进不同任务的同时优化。然而,在知识迁移的过程中负迁移现象很难避免。为了尽可能避免负迁移,因此提出了一种基于核化方法的多目标多任务优化算法。由于在高维空间中更容易捕捉到数据之间的非线性关系,因此提出将不同的任务映射到再生核希尔伯特空间,构建二者间的非线性关系,并通过该非线性关系将任务间的知识进行有效迁移。将所提算法与三个有代表性的多任务优化算法在多目标多任务优化基准测试问题上进行了实验结果的比较,实验结果表明其具有良好的优化性能,并且表明通过这种方法能有效减少负迁移现象。 展开更多
关键词 多目标多任务优化 进化计算 知识迁移 核化方法 非线性关系
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基于关联信息增强与关系平衡的场景图生成方法 被引量:1
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作者 李林昊 韩冬 +2 位作者 董永峰 李英双 王振 《计算机应用》 北大核心 2025年第3期953-962,共10页
利用场景图的上下文信息可以帮助模型理解目标之间的关联作用;然而,大量不相关的目标可能带来额外噪声,进而影响信息交互,造成预测偏差。在嘈杂且多样的场景中,即使几个简单的关联目标,也足够推断目标所处的环境信息,并消除其他目标的... 利用场景图的上下文信息可以帮助模型理解目标之间的关联作用;然而,大量不相关的目标可能带来额外噪声,进而影响信息交互,造成预测偏差。在嘈杂且多样的场景中,即使几个简单的关联目标,也足够推断目标所处的环境信息,并消除其他目标的歧义信息。此外,在面对真实场景中的长尾偏差数据时,场景图生成(SGG)的性能难以令人满意。针对上下文信息增强和预测偏差的问题,提出一种基于关联信息增强与关系平衡的SGG(IERB)方法。IERB方法采用一种二次推理结构,即根据有偏场景图的预测结果重新构建不同预测视角下的关联信息并平衡预测偏差。首先,聚焦不同视角下的强相关目标以构建上下文关联信息;其次,利用树型结构的平衡策略增强尾部关系的预测能力;最后,采用一种预测引导方式在已有场景图的基础上预测优化。在通用的数据集Visual Genome上的实验结果表明,与3类基线模型VTransE(Visual Translation Embedding network)、Motif和VCTree(Visual Context Tree)相比,所提方法在谓词分类(PredCls)任务下的均值召回率mR@100分别提高了11.66、13.77和13.62个百分点,验证了所提方法的有效性。 展开更多
关键词 场景图生成 信息增强 有偏预测 关系平衡 预测优化
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基于多模态深度学习的专利自动分类方法研究 被引量:1
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作者 谢小东 吴洁 +2 位作者 盛永祥 唐健廷 于娱 《情报杂志》 北大核心 2025年第5期199-206,F0003,共9页
[研究目的]构建基于多模态深度学习的专利自动分类方法,提高专利分类效率,加速专利审查过程,节约人力物力成本。[研究方法]利用BERT-for-Patents和VGG19模型分别提取专利文本和图像模态特征,通过逐级拼接对两种模态特征进行融合和联合训... [研究目的]构建基于多模态深度学习的专利自动分类方法,提高专利分类效率,加速专利审查过程,节约人力物力成本。[研究方法]利用BERT-for-Patents和VGG19模型分别提取专利文本和图像模态特征,通过逐级拼接对两种模态特征进行融合和联合训练,在同类型节点的低度值节点之间构建连边优化节点间引用网络,最后采用GraphSAGE模型进行专利自动分类。[研究结果/结论]研究表明,所构建方法部的分类准确率达到95.71%,大类的分类准确率达到90.19%,小类的分类准确率达到84.42%,各项指标均显著优于基线模型。该方法有效利用了专利文本和图像信息,弥补了单模态信息的不足,增强了模型对复杂专利内容的理解能力,提高了专利自动分类的细分度和准确性,同时有效补充了现有专利自动分类研究框架。 展开更多
关键词 多模态 深度学习 专利分类 文本特征 图像特征 特征融合 网络关系优化
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基于最优化算法的北京市新一代天气雷达Z-R关系研究 被引量:17
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作者 袁晓清 倪广恒 +1 位作者 潘安君 魏立川 《水文》 CSCD 北大核心 2010年第1期1-6,共6页
运用最优化方法,选取北京市新一代天气雷达2007年4场降雨的基数据资料与对应的雨量计资料进行Z-R关系研究,对不同类型的降雨和不同距离范围的雷达估测点分别优化。结果表明:运用优化后的Z-R关系估测降水量的误差要比缺省的Z-R关系式直... 运用最优化方法,选取北京市新一代天气雷达2007年4场降雨的基数据资料与对应的雨量计资料进行Z-R关系研究,对不同类型的降雨和不同距离范围的雷达估测点分别优化。结果表明:运用优化后的Z-R关系估测降水量的误差要比缺省的Z-R关系式直接计算出降水量的误差小得多;层状云降水的估测结果优于对流云降水的估测;距离雷达站较近的地区其估测结果优于较远的地区。 展开更多
关键词 新一代天气雷达 z-r关系 最优化方法 北京
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