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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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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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Predicting Academic Performance Levels in Higher Education:A Data-Driven Enhanced Fruit Fly Optimizer Kernel Extreme Learning Machine Model 被引量:1
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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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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:18
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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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雷达估测对流性降水的误差空间分布及Z-R关系的优化 被引量:12
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作者 杨杰 刘黎平 +1 位作者 赵城城 吴亚昊 《高原气象》 CSCD 北大核心 2015年第6期1785-1796,共12页
新一代天气雷达联合雨量站数据进行定量降水估测中,雷达回波强度和雨量站观测值较好的匹配是准确拟合出Z-R关系的关键。对流性降水回波强度具有时空变化大的特点,严重影响了雷达和雨量站数据的匹配以及定量降水估测的精度。利用河南地区... 新一代天气雷达联合雨量站数据进行定量降水估测中,雷达回波强度和雨量站观测值较好的匹配是准确拟合出Z-R关系的关键。对流性降水回波强度具有时空变化大的特点,严重影响了雷达和雨量站数据的匹配以及定量降水估测的精度。利用河南地区3次强对流天气过程的雷达和雨量站数据,通过分析雷达对流性降水与地面雨量站观测值的误差空间分布,找到如下规律:雷达回波强度严重高估点和低估点大部分位于强回波的边缘地区(单点回波强度随时间变化较大);部分位于强回波中心的雨量站观测值为零(部分时刻)。通过分析可知,突发的强降水和强回波中心容易造成雨量站观测值误差较大,因此对Z-R关系拟合造成了较大的影响。根据对流性降水回波强度变化特点和本文得到的回波强度与雨量站雨量匹配关系,在Z-R关系拟合中,提出了加入回波强度随时间变化的指标对误差较大雨量站进行剔除的方法,也提出了一种优化的回波强度平均方法和累积时间,得到了用于对流性降水估测的最佳方案。详细分析以上因素对降水估测的影响表明,通过根据回波强度随时间变化的指标对雨量站进行剔除和使用最佳降水估测方案,提高了对流性降水估测的精度。 展开更多
关键词 对流性降水 误差空间分布 z-r关系优化 三维拼图
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Mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device 被引量:2
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作者 Xin Xu Na Xu +3 位作者 Wei Zhang Junwen Wang Yao Li Chen Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第12期37-48,共12页
Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow... Mass transfer performance of gas–liquid two-phase flow at microscale is the basis of application of microreactor in gas–liquid reaction systems.At present,few researches on the mass transfer property of annular flow have been reported.Therefore,the mass transfer mechanism and relationship of gas–liquid annular flow in a microfluidic cross-junction device are studied in the present study.We find that the main factors,i.e.,flow pattern,liquid film thickness,liquid hydraulic retention time,phase interface fluctuation,and gas flow vorticity,which influence the flow mass transfer property,are directly affected both by gas and liquid flow velocities.But the influences of gas and liquid velocities on different mass transfer influencing factors are different.Thereout,the fitting relationships between gas and liquid flow velocities and mass transfer influencing factors are established.By comparing the results from calculations using fitting equations and simulations,it shows that the fitting equations have relatively high degrees of accuracy.Finally,the Pareto front,namely the Pareto optimal solution set,of gas and liquid velocity conditions for the best flow mass transfer property is obtained using the method of multi-objective particle swarm optimization.It is proved that the mass transfer property of the gas–liquid two-phase flow can be obviously enhanced under the guidance of the obtained Pareto optimal solution set through experimental verification. 展开更多
关键词 Gas-liquid microreactor Annular flow Mass transfer mechanism Mass transfer relationship Multi-objective particle swarm optimization
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Water-cut rising mechanism and optimized water injection technology for deepwater turbidite sandstone oilfield: A case study of AKPO Oilfield in Niger Delta Basin, West Africa 被引量:1
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作者 YUAN Zhiwang YANG Baoquan +5 位作者 YANG Li GU Wenhuan CHEN Xiao KANG Botao LI Chenxi ZHANG Huilai 《Petroleum Exploration and Development》 2018年第2期302-311,共10页
Through the analysis of the reservoir connection relationship and the water-cut rising rules after water breakthrough in the highly volatile oil AKPO oilfield, a new model of water-cut rising was established, and the ... Through the analysis of the reservoir connection relationship and the water-cut rising rules after water breakthrough in the highly volatile oil AKPO oilfield, a new model of water-cut rising was established, and the timing and strategy of water injection were put forward. The water-cut rising shapes of producers after water breakthrough can be divided into three types, and their water-cut rising mechanism is mainly controlled by reservoir connectivity. For the producers which directly connect with injectors in the single-phase sand body of the single-phase channel or lobe with good reservoir connectivity, the water-cut rising curve is "sub-convex". For the producers which connect with injectors through sand bodies developed in multi-phases with good inner sand connectivity but poorer physical property and connectivity at the overlapping parts of sands, the response to water injection is slow and the water-cut rising curve is "sub-concave". For the producers which connect with injectors through multi-phase sand bodies with reservoir physical properties, connectivity in between the former two and characteristics of both direct connection and overlapping connection, the response to water injection is slightly slower and the water-cut rising curve is "sub-S". Based on ratio relationship of oil and water relative permeability, a new model of water cut rising was established. Through the fitting analysis of actual production data, the optimal timing and corresponding technology for water injection after water breakthrough were put forward. Composite channel and lobe reservoirs can adopt water injection strategies concentrating on improving the vertical sweep efficiency and areal sweep efficiency respectively. This technology has worked well in the AKPO oilfield and can guide the development of similar oilfields. 展开更多
关键词 DEEPWATER field development volatile oil RESERVOIR water-cut RISING type RESERVOIR connection relationship water-cut RISING MECHANISM optimized WATER injection
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Consistency in <i>Z</i>-<i>R</i>Relationship Variability Regardless Precipitating Systems, Climatic Zones Observed from Two Types of Disdrometer 被引量:1
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作者 Bakary Bamba Abé Delfin Ochou +1 位作者 Eric-Pascal Zahiri Modeste Kacou 《Atmospheric and Climate Sciences》 2014年第5期941-955,共15页
Data from rain Drop Size Distributions gathered on five sites in Africa as well as those of the pilot site in Kourou (French Guyana, South America), located in different climatic zones, and collected by two types of d... Data from rain Drop Size Distributions gathered on five sites in Africa as well as those of the pilot site in Kourou (French Guyana, South America), located in different climatic zones, and collected by two types of disdrometer (the impact JW RD-69 disdrometer and the Optical Spectro-Pluviometer, OSP) are used to study the consistency of the reflectivity factor-rain rate at the ground (Z-R) relationship variability. The results clearly confirm that the relationship Z-R knows a large spatial variability, from a type of precipitation to another and within the same precipitation regardless the type of disdrometer used for DSD measurements. Base on the similarity of the relations reflectivity factor-rain rate and ratio median volume diameter over the total number of drops-rain rate, the variability of the Z-R coefficients (A, b) through the simultaneously implication of the size and number of drops which characterize the DSD was exhibited. It was shown that the relationships A-α and b-β designed to understand the involvement of parameters D0 and NT of DSD in the variability of the relationship Z-R are similar regardless the types of disdrometer used. However, the relations A-α in the Sahelian region appear to deviate from those of Guinean, equatorial and Soudanian zones. The plausible reasons were discussed. 展开更多
关键词 Drop Size Distributions CONSISTENCY in z-r relationship VARIABILITY Squall Lines Thunderstorm Stratiform Rain JW RD-69 DISDROMETER Optical Spectro-Pluviometer OSP
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优化Z-R关系及其在北京地区面雨量估测中的应用 被引量:2
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作者 袁晓清 倪广恒 《广东水利电力职业技术学院学报》 2011年第4期1-7,共7页
运用最优化方法,选取北京市新一代天气雷达2007年5场降雨的基数据资料与对应的地面雨量计资料进行Z-R关系研究,对比由雨量计观测值和雷达估测值插值得到的面雨量分布情况。结果表明:采用缺省的Z-R关系估算出的区域面雨量普遍偏小很多,... 运用最优化方法,选取北京市新一代天气雷达2007年5场降雨的基数据资料与对应的地面雨量计资料进行Z-R关系研究,对比由雨量计观测值和雷达估测值插值得到的面雨量分布情况。结果表明:采用缺省的Z-R关系估算出的区域面雨量普遍偏小很多,优化后雷达估测的雨强分布与雨量站点测量的雨强分布更接近,且雷达定量估测区域面雨量的精度有了较大提高。 展开更多
关键词 新一代天气雷达 Z—R关系 最优化方法 面雨量
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Accurate Registration of Remote Sensing Images Based on Local Optimal Transformation
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作者 Bo Wang Changqing Li +2 位作者 Shi Tang Zhiqiang Zhou Hong Zhao 《Journal of Beijing Institute of Technology》 EI CAS 2019年第2期371-382,共12页
As the basic work of image stitching and object recognition,image registration played an important part in the image processing field.Much previous work in registration accuracy and realtime performance progressed ver... As the basic work of image stitching and object recognition,image registration played an important part in the image processing field.Much previous work in registration accuracy and realtime performance progressed very slowly,especially in registrating images with line feature.An innovative method for image registration based on lines is proposed,it can effectively improve the accuracy and real-time performance of image registration.The line feature can deal with some registration problems where point feature does not work.Our registration process is divided into two parts.The first part determines the rough registration transformation relation between reference image and test image.Then the similarity degree among different transformation and modified nonmaximum suppression(MNMS)algorithms are obtained,which produce local optimal solution to optimize the rough registration transformation.The final optimal registration relation can be obtained from two registration parts according to the match scores.The experimental results show that the proposed method makes a more accurate registration relation and performs better in real-time situation. 展开更多
关键词 initial REGISTRATION relationship accurate REGISTRATION relationship SIMILARITY DEGREE local optimal TRANSFORMATION modified non-maximum suppression(MNMS)algorithm
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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:6
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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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