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An Approach to Detect Structural Development Defects in Object-Oriented Programs
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作者 Maxime Seraphin Gnagne Mouhamadou Dosso +1 位作者 Mamadou Diarra Souleymane Oumtanaga 《Open Journal of Applied Sciences》 2024年第2期494-510,共17页
Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detecti... Structural development defects essentially refer to code structure that violates object-oriented design principles. They make program maintenance challenging and deteriorate software quality over time. Various detection approaches, ranging from traditional heuristic algorithms to machine learning methods, are used to identify these defects. Ensemble learning methods have strengthened the detection of these defects. However, existing approaches do not simultaneously exploit the capabilities of extracting relevant features from pre-trained models and the performance of neural networks for the classification task. Therefore, our goal has been to design a model that combines a pre-trained model to extract relevant features from code excerpts through transfer learning and a bagging method with a base estimator, a dense neural network, for defect classification. To achieve this, we composed multiple samples of the same size with replacements from the imbalanced dataset MLCQ1. For all the samples, we used the CodeT5-small variant to extract features and trained a bagging method with the neural network Roberta Classification Head to classify defects based on these features. We then compared this model to RandomForest, one of the ensemble methods that yields good results. Our experiments showed that the number of base estimators to use for bagging depends on the defect to be detected. Next, we observed that it was not necessary to use a data balancing technique with our model when the imbalance rate was 23%. Finally, for blob detection, RandomForest had a median MCC value of 0.36 compared to 0.12 for our method. However, our method was predominant in Long Method detection with a median MCC value of 0.53 compared to 0.42 for RandomForest. These results suggest that the performance of ensemble methods in detecting structural development defects is dependent on specific defects. 展开更多
关键词 Object-Oriented Programming Structural Development Defect Detection Software Maintenance Pre-Trained Models Features Extraction BAGGING Neural Network
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基于MobileNet-SSD的铁路信号灯检测识别 被引量:8
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作者 王焕民 张建柏 +1 位作者 裴华艳 蒋兆远 《兰州交通大学学报》 CAS 2020年第4期66-70,共5页
为解决铁路轨旁信号灯的定位与实时检测问题,在深入分析传统SSD算法与MobileNet模型的基础上,将MobileNet模型的最后平均池化层、全连接层转换为SSD算法的多尺度特征映射层,提出了一种基于MobileNet-SSD的铁路信号灯检测算法.实验结果表... 为解决铁路轨旁信号灯的定位与实时检测问题,在深入分析传统SSD算法与MobileNet模型的基础上,将MobileNet模型的最后平均池化层、全连接层转换为SSD算法的多尺度特征映射层,提出了一种基于MobileNet-SSD的铁路信号灯检测算法.实验结果表明:该算法克服了传统SSD算法对小目标识别不准确、检测实时性较差的问题,检测速度更快,准确率更高;在50 m监控范围内,算法的平均检测准确率达到85%以上,同时具有25帧/s的实时识别能力. 展开更多
关键词 铁路信号灯检测 MobileNet-SSD 目标检测 深度学习
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Preliminary Study of Chemical Elements Distribution in Petroleum Source Rocks Donga and Yogou Formations of the Termit Sedimentary Basin (Est-Niger)
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作者 Alassane Ibrahim Maman Bachir Abdoulaye Dan Makaou Oumarou +2 位作者 Baraou Idi Souley Kouakou Alponse Yaou Abdoulwahid Sani 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期49-62,共14页
XRF and EDX analyses were carried out on 18 batches of representative raw samples to determine the distribution of major chemical elements in the petroleum source rocks of Donga and Yogou formations of Termit sediment... XRF and EDX analyses were carried out on 18 batches of representative raw samples to determine the distribution of major chemical elements in the petroleum source rocks of Donga and Yogou formations of Termit sedimentary basin. The chemical composition of these formations is dominated by silicon (Si), aluminum (Al) and iron (Fe). This is consistent with the oxide composition, which is also dominated by silicon oxide (SiO2), aluminum oxide (Al<sub>2</sub>O<sub>3</sub>) and iron monoxide (FeO). No less important chemical elements are calcium (Ca), potassium (K), sulfur (S), titanium (Ti), magnesium (Mg), manganese (Mn) and barium (Ba), as well as some of their oxides. All these major chemical elements are carried by silicate detrital minerals associated with pyrite and goethite and/or clay minerals such as kaolinite and interstratified illite, smectite and chlorite. This trend is illustrated by the values of the Si/Al and SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratios. 展开更多
关键词 DISTRIBUTION Major Elements Source Rocks Donga Formation Yogou Formation Termit Basin
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基于T-S模糊故障树的制动系统可靠性分析 被引量:6
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作者 周亚辉 齐金平 +1 位作者 李少雄 王康 《实验室研究与探索》 CAS 北大核心 2021年第6期24-28,47,共6页
为解决动车组制动系统由于工作条件多样及内部结构复杂而呈现出的多故障状态以及故障机理模糊、故障关系不确定等问题,应用T-S模糊故障树的逻辑关系明确且可处理事件的不确定能力,结合基于信心指数修正的专家调查法,进行制动系统模型构... 为解决动车组制动系统由于工作条件多样及内部结构复杂而呈现出的多故障状态以及故障机理模糊、故障关系不确定等问题,应用T-S模糊故障树的逻辑关系明确且可处理事件的不确定能力,结合基于信心指数修正的专家调查法,进行制动系统模型构建及重要度计算。得出了动车组制动系统薄弱环节,可为系统检修提供参考。 展开更多
关键词 动车组 制动系统 T-S模糊故障树 专家调查法 重要度
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rt-PA静脉溶栓联合灯盏细辛注射液治疗急性缺血性脑卒中的效果分析
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作者 沈碧胜 李旷怡 +5 位作者 张英俭 梁章荣 陈景利 洪丹东 宁驰 彭烈标 《当代医药论丛》 2022年第9期102-106,共5页
目的:探讨用重组组织型纤溶酶原激活剂(rt-PA)静脉溶栓疗法联合灯盏细辛注射液治疗急性缺血性脑卒中的临床效果。方法:选取2018年1月至2019年6月佛山市中医院卒中中心收治的急性缺血性脑卒中患者84例(行rt-PA静脉溶栓治疗),对其临床资... 目的:探讨用重组组织型纤溶酶原激活剂(rt-PA)静脉溶栓疗法联合灯盏细辛注射液治疗急性缺血性脑卒中的临床效果。方法:选取2018年1月至2019年6月佛山市中医院卒中中心收治的急性缺血性脑卒中患者84例(行rt-PA静脉溶栓治疗),对其临床资料进行回顾性研究。按是否使用灯盏细辛注射液进行治疗将其分为观察组(46例)及对照组(38例),比较两组患者的临床疗效、NIHSS评分、Barthel评分和不良反应的发生情况。结果:观察组患者治疗的总有效率明显高于对照组患者,P<0.05。治疗后,两组患者的NIHSS评分均较治疗前显著降低,P<0.05;观察组患者的NIHSS评分低于对照组患者,P<0.05。治疗后,两组患者的Barthel评分均较治疗前显著提高,P<0.05;观察组患者的Barthel评分高于对照组患者,P<0.05。治疗后,两组患者均未出现血压降低、头痛、过敏、胸闷、心悸等不良反应,其血尿常规指标、肝肾功能指标及电解质指标均无异常。结论:用rt-PA静脉溶栓疗法联合灯盏细辛注射液治疗急性缺血性脑卒中的临床效果显著,可有效地减轻患者的临床症状,改善其神经功能,提高其日常生活活动能力和生活质量,且安全性较高。 展开更多
关键词 急性缺血性脑卒中 RT-PA静脉溶栓 灯盏细辛注射液 NIHSS评分 Barthel评分
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含沙量监测的wavelet-Kalman多尺度融合研究 被引量:3
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作者 付立彬 刘明堂 +2 位作者 王丽 秦泽宁 杨阳蕊 《人民黄河》 CAS 北大核心 2018年第9期23-27,共5页
为解决黄河含沙量监测时传感器易受环境因素影响的问题,简述了音频共振法测量含沙量的原理,探讨了音频共振传感器的谐振频率和含沙量监测之间的关系,提出了贯序式wavelet-Kalman多尺度融合模型,对音频共振传感器的谐振频率进行小波分解... 为解决黄河含沙量监测时传感器易受环境因素影响的问题,简述了音频共振法测量含沙量的原理,探讨了音频共振传感器的谐振频率和含沙量监测之间的关系,提出了贯序式wavelet-Kalman多尺度融合模型,对音频共振传感器的谐振频率进行小波分解,把含沙量数据组成贯序式数据块进行多尺度分析,提取含沙量信号序列中的突变值,建立了Kalman融合方程,将温度信息作为控制信号,消除了环境因素对含沙量监测的影响,并进行了含沙量测量的反演和误差分析。结果表明:贯序式wavelet-Kalman多尺度融合模型能够有效地消除环境影响,提高系统测量的精度和稳定性,平均绝对误差为3.95 kg/m^3,均方根误差为3.13 kg/m^3,比其他反演模型的误差小。 展开更多
关键词 音频共振法 贯序式 小波多尺度分析 卡尔曼融合 含沙量监测
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Handling Qualities of a New Last-Mile Vehicle
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作者 Jordi D’hondt Dominiek Degryse +2 位作者 Eric Demeester Peter Slaets Marc Juwet 《Journal of Transportation Technologies》 2022年第1期137-158,共22页
This paper assesses the vehicle dynamics of a new cargo bike concept developed for euro pallet sized cargo. The cargo bike developed is for last-mile delivery. Different aspects of manoeuvrability and stability are ex... This paper assesses the vehicle dynamics of a new cargo bike concept developed for euro pallet sized cargo. The cargo bike developed is for last-mile delivery. Different aspects of manoeuvrability and stability are examined using a series of manoeuvres based on tests from the automotive industry combined with bicycle industry regulations. These manoeuvres objectively evaluate and determine the handling capabilities of the cargo bike concept. Those tests can be compared using the results of the benchmark vehicles. The results conclude the new cargo bike has proper vehicle dynamics above the majority of benchmark vehicles but there is still room for improvement. 展开更多
关键词 Cargo Bike Last-Mile Delivery Handling Qualities E-COMMERCE
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基于FinBERT-CNN的股吧评论情感分析方法 被引量:3
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作者 刘薇 姜青山 +2 位作者 蒋泓毅 胡金帅 曲强 《集成技术》 2022年第1期27-39,共13页
我国股市波动受投资者情绪变化影响较大,通过对股吧等金融交流平台上投资者的评论进行情感分析,能够帮助投资者更好地了解股票市场的变化。现有的情感分析方法是利用模型对股票评论集进行分析,但缺少优质的股票评论标注数据集用于模型训... 我国股市波动受投资者情绪变化影响较大,通过对股吧等金融交流平台上投资者的评论进行情感分析,能够帮助投资者更好地了解股票市场的变化。现有的情感分析方法是利用模型对股票评论集进行分析,但缺少优质的股票评论标注数据集用于模型训练,且单一模型提取股票评论特征较为片面,模型的准确性有待提高。该文针对股吧平台上的评论数据,提出一种基于FinBERT-CNN的股吧评论情感分析方法,该方法通过FinBERT预训练模型学习股吧评论数据语义特征,解决缺乏股吧评论标注数据集的问题,并利用卷积神经网络学习股吧评论的局部特征,使模型充分学习股吧评论特征,提高模型情感分类的准确性。实验结果表明,基于FinBERT-CNN的股吧评论情感分析方法均优于现有情感分析方法。此外,通过基于股吧评论情感的股票市场关联分析,验证了股吧评论情感变化与股市波动存在相关性。 展开更多
关键词 股吧评论 情感分析 预训练模型 FinBERT 卷积神经网络
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Designing a High-Performance Deep Learning Theoretical Model for Biomedical Image Segmentation by Using Key Elements of the Latest U-Net-Based Architectures
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作者 Andreea Roxana Luca Tudor Florin Ursuleanu +5 位作者 Liliana Gheorghe Roxana Grigorovici Stefan Iancu Maria Hlusneac Cristina Preda Alexandru Grigorovici 《Journal of Computer and Communications》 2021年第7期8-20,共13页
Deep learning (DL) has experienced an exponential development in recent years, with major impact in many medical fields, especially in the field of medical image and, respectively, as a specific task, in the segmentat... Deep learning (DL) has experienced an exponential development in recent years, with major impact in many medical fields, especially in the field of medical image and, respectively, as a specific task, in the segmentation of the medical image. We aim to create a computer assisted diagnostic method, optimized by the use of deep learning (DL) and validated by a randomized controlled clinical trial, is a highly automated tool for diagnosing and staging precancerous and cervical cancer and thyroid cancers. We aim to design a high-performance deep learning model, combined from convolutional neural network (U-Net)-based architectures, for segmentation of the medical image that is independent of the type of organs/tissues, dimensions or type of image (2D/3D) and to validate the DL model in a randomized, controlled clinical trial. We used as a methodology primarily the analysis of U-Net-based architectures to identify the key elements that we considered important in the design and optimization of the combined DL model, from the U-Net-based architectures, imagined by us. Secondly, we will validate the performance of the DL model through a randomized controlled clinical trial. The DL model designed by us will be a highly automated tool for diagnosing and staging precancers and cervical cancer and thyroid cancers. The combined model we designed takes into account the key features of each of the architectures Overcomplete Convolutional Network Kite-Net (Kite-Net), Attention gate mechanism is an improvement added on convolutional network architecture for fast and precise segmentation of images (Attention U-Net), Harmony Densely Connected Network-Medical image Segmentation (HarDNet-MSEG). In this regard, we will create a comprehensive computer assisted diagnostic methodology validated by a randomized controlled clinical trial. The model will be a highly automated tool for diagnosing and staging precancers and cervical cancer and thyroid cancers. This would help drastically minimize the time and effort that specialists put into analyzing medical images, help to achieve a better therapeutic plan, and can provide a “second opinion” of computer assisted diagnosis. 展开更多
关键词 Combined Model of U-Net-Based Architectures Medical Image Segmentation 2D/3D/CT/RMN Images
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A Conceptual and Computational Framework for Aspect-Based Collaborative Filtering Recommender Systems 被引量:1
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作者 Samin Poudel Marwan Bikdash 《Journal of Computer and Communications》 2023年第3期110-130,共21页
Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspe... Many datasets in E-commerce have rich information about items and users who purchase or rate them. This information can enable advanced machine learning algorithms to extract and assign user sentiments to various aspects of the items thus leading to more sophisticated and justifiable recommendations. However, most Collaborative Filtering (CF) techniques rely mainly on the overall preferences of users toward items only. And there is lack of conceptual and computational framework that enables an understandable aspect-based AI approach to recommending items to users. In this paper, we propose concepts and computational tools that can sharpen the logic of recommendations and that rely on users’ sentiments along various aspects of items. These concepts include: The sentiment of a user towards a specific aspect of a specific item, the emphasis that a given user places on a specific aspect in general, the popularity and controversy of an aspect among groups of users, clusters of users emphasizing a given aspect, clusters of items that are popular among a group of users and so forth. The framework introduced in this study is developed in terms of user emphasis, aspect popularity, aspect controversy, and users and items similarity. Towards this end, we introduce the Aspect-Based Collaborative Filtering Toolbox (ABCFT), where the tools are all developed based on the three-index sentiment tensor with the indices being the user, item, and aspect. The toolbox computes solutions to the questions alluded to above. We illustrate the methodology using a hotel review dataset having around 6000 users, 400 hotels and 6 aspects. 展开更多
关键词 Recommender System Collaborative Filtering Aspect based recommendation Recommendation System Framework Aspect Sentiments
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Long Pulse Operation of High Performance Plasmas in JT-60U
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作者 S.IDE 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第1期1-4,共4页
Recent experimental progress in JT-60U advanced tokamak research is presented: sustainment of the normalized beta (βN)- 3 in a normal magnetic shear plasma, the bootstrap current fraction (fBs) - 45% in a weak s... Recent experimental progress in JT-60U advanced tokamak research is presented: sustainment of the normalized beta (βN)- 3 in a normal magnetic shear plasma, the bootstrap current fraction (fBs) - 45% in a weak shear plasma and - 75% in a reversed magnetic shear plasma in a nearly fully non-inductive current drive condition for longer than the current relaxation time. Achievement of high-density, high-radiation fraction together with high-confinement in advanced plasmas is demonstrated. Achievements and findings in long pulse operations after system modification are presented as well. A 65 s discharge of Ip = 0.7 MA was successfully obtained. As a result, high-βN of 2.3 was successfully sustained for a very long period of 22.3 s. In addition, a 30 s standard ELMy H-mode plasma of Ip up to 1.4 MA was also obtained. Effectiveness of divertor pumping to control particle recycling and the electron density under the saturated wall retention was demonstrated. These achievements and issues in development are discussed. 展开更多
关键词 transport properties MAGNETOHYDRODYNAMICS TOKAMAKS
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Potential Probiotic Tiger Nut-Cashew Nut-Milk Production by Fermentation with Two Lactic Bacteria Isolated from Ivorian Staple Foods
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作者 Allah Antoine Assamoi Koua Atobla +1 位作者 Djeneba H. Ouattara Raïssa Thénéthio Koné 《Agricultural Sciences》 CAS 2023年第4期584-600,共17页
Probiotification of plant milk can improve its sensory and health-promoting properties. As traditional fermented foods where lactic acid bacteria (LAB) are present have been associated with beneficial effects on human... Probiotification of plant milk can improve its sensory and health-promoting properties. As traditional fermented foods where lactic acid bacteria (LAB) are present have been associated with beneficial effects on human health, the beneficial effects of two LAB recently isolated from two current Ivorian staple foods (a pepper and a traditional beer) were screened. These two strains LAC 1 (Lactobacillus plantarum) and LAC 2 (Pediococcus acidilactici) which presented probiotic, exopolysaccharides, inflammatory and anti-oxidant activities, were used to ferment a composite plant milk of tiger-nut and cashew (80/20) compared to two starters of a commercial yogourt. The obtained plant milks SCT 2 and SCT 3 with a significant increase in their antioxidant and/or anti-inflammatory activities and lactic bacteria contents were more preferred by consumers than SCT 1 obtained by fermentation of the commercial yogourt starters. The mixing of LAC 1 and LAC 2 was not beneficial. SCT 2 (with an anti-inflammatory activity of 31.38% and an anti-oxidant activity of 17.30%) and SCT 3 (with an anti-oxidant activity of 22.28) could be further tested in animal models to verify their nutrition-health claims. 展开更多
关键词 Probiotic Staple Food Lactic Acid ANTI-OXIDANT ANTI-INFLAMMATORY
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Prevention of Gastrointestinal Pathologies: Comparative Study of the Microbial Flora of the Sanitary Surfaces of the Toilets of Students and Staff of the Félix Houphouët-Boigny University
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作者 N’gbesso Jean-Paul N’gbesso Beudje Félicité +3 位作者 Okoubo Née A. Nicaise N’guessan Mambey Serge Juili Landry A. Arra Allou Aime Constantin Ahoua 《Open Journal of Medical Microbiology》 2020年第3期129-138,共10页
<div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transm... <div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transmissible by hand such as gastrointestinal pathologies constitute a real public health problem, especially in sub-Saharan Africa where hygienic conditions are precarious. This study took place at Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny</span></span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> University from April to August 2018. The samples were taken from toilet surfaces such as doorknobs, tap heads, flush push buttons and seats WC. A total of three hundred and sixty-eight (368) samples were obtained, including 170 from the staff toilets and 198 from the student toilets. The results revealed the presence of total coliforms, </span><i><span style="font-family:Verdana;">Escherichia</span></i><span style="font-family:Verdana;"> spp and </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"> spp. The surfaces of student toilets were the most contaminated surfaces. The presence of entero-bacteria on the contact surfaces of the toilets of the Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny university represents a health risk for the university population.</span></span> </div> 展开更多
关键词 Communicable Diseases Hand HYGIENE ENTEROBACTERIACEAE TOILET UNIVERSITY
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Improving the Quality of Rubber Plants in Bagged Nurseries by the Use of Compost-Based Culture Substrates
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作者 Jean Lopez Essehi Eric Francis Soumahin +2 位作者 Guy Fernand Yao Samuel Obouayeba Albert Yao-Kouamé 《Open Journal of Soil Science》 2021年第11期567-585,共19页
The decrease of fertility soils, the rarity of quality potting soil used to fill nursery bags, the high cost of chemical fertilisers and the problems associated with their use are leading planters and rubber nurseryme... The decrease of fertility soils, the rarity of quality potting soil used to fill nursery bags, the high cost of chemical fertilisers and the problems associated with their use are leading planters and rubber nurserymen in developing and/or expanding areas to look for alternative and sustainable fertilization. In this perspective, a trial was carried out at Research Station of CNRA-Bimbresso and in a farmer’s environment in order to evaluate the agronomic quality of compost made from chicken droppings and dry <em>Panicum maximum</em> straw to improve the growth of rubber plants in bagged nurseries. Mixtures based on potting soil and/or compost in different proportions were prepared. The follow-up of the trial focused on determination of the physico-chemical characteristics of the soils, measurement of the parameters of vegetative growth and the grafting success rate evaluation of rubber plants in nursery. The results obtained show that compost-based crop substrates increase soil organic matter, nitrogen, exchangeable bases, etc., in proportion to the doses applied. For the pH, the application of compost resulted in a reduction in soil acidity of about 1.3 unit compared to the initial values at the two study sites. The vegetative behaviour of the rubber plants also shows that qualitative (height and collar diameter) and quantitative (grafting success rate) improvements were recorded in the plants raised in compost-based substrates. The production of rubber plants in bagged nurseries was optimal with compost doses of 27 t<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup> (at Bimbresso, in the southeast) and 27 t<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup> combined with fractionated application of urea (at Kimoukro, in the centre), which under the conditions of the present study may be the recommended doses on rubber plants in bagged nurseries at C<span style="white-space:nowrap;">&#244;</span>te d’Ivoire. 展开更多
关键词 COMPOST Soils Parameters Vegetative Growth Hevea brasiliensis Côte d’Ivoire
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松辽盆地齐家凹陷南部青山口组一段古环境及其对有机质富集的控制作用 被引量:2
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作者 姚玉来 肖飞 +3 位作者 李士超 杨建国 公繁浩 王杰 《中国石油大学学报(自然科学版)》 北大核心 2025年第1期59-71,共13页
基于齐家凹陷南部松页油1井青一段详细的岩心观察描述以及测井元素数据分析,应用元素质量比w(Mg)/w(Ca)、w(Th)/w(U)、(w(Fe)+w(Al))/(w(Ca)+w(Mg))等指示参数,恢复青一段沉积时期古环境,探讨控制有机质富集的古环境因素。结果表明:青... 基于齐家凹陷南部松页油1井青一段详细的岩心观察描述以及测井元素数据分析,应用元素质量比w(Mg)/w(Ca)、w(Th)/w(U)、(w(Fe)+w(Al))/(w(Ca)+w(Mg))等指示参数,恢复青一段沉积时期古环境,探讨控制有机质富集的古环境因素。结果表明:青一段中下部为半深湖和深湖亚相沉积,上部为浅湖亚相,中下部层状暗色泥页岩更为发育;青一段沉积时期经历气候由潮湿到半潮湿,湖水盐度由微咸水到淡水,还原条件由强到弱,水深由深变浅,水动力由停滞到低能的古环境演变过程;青一段自下而上泥页岩TOC含量逐渐降低,TOC与氧化还原条件、古气候和古水深指标相关性最大,表明有机质的富集主要受控于泥页岩沉积时期的氧化还原环境、古气候和古水深;潮湿气候、缺氧环境下的深水区更有利于有机质的富集和保存;深湖相层状富有机质暗色泥页岩是页岩油勘探的有利目标。 展开更多
关键词 沉积相 古环境 页岩油 有机质富集 松辽盆地 青山口组一段
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科学计量学的跨学科研究范式演变和发展进路 被引量:2
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作者 陈悦 谢俊杰 王智琦 《科学学研究》 北大核心 2025年第2期291-299,共9页
作为以量化和数学方法为主来测度科学的一门学问,科学计量学已经成为科技政策研究不可缺少的方法性支撑工具,然而对其进行科学测度的质疑声音也从未停止过。本文试图从科学计量学源起和发展的复杂历史背景中去把握这门学问的特点和价值... 作为以量化和数学方法为主来测度科学的一门学问,科学计量学已经成为科技政策研究不可缺少的方法性支撑工具,然而对其进行科学测度的质疑声音也从未停止过。本文试图从科学计量学源起和发展的复杂历史背景中去把握这门学问的特点和价值,厘清其与科学学、科学技术史、科学社会学、科学哲学、文献计量学、科技政策研究、计算社会学之间复杂而又有秩序的关联和脉络,强调科学计量学只有在跨学科研究范式中,才有可能实现其工具理性和价值理性的统一,从而更为客观有效地测度科学,从而为提供科技发展洞见提供有力支撑。本文的主要观点是,科学计量学源于对科学与社会关系的系统性思考,这既包括知识论视角的科学自身,又包括社会学视角的科学活动;科学计量学是科学学强调用科学的方法来研究科学的重要特征之一,而其有效应用的前提是将科学视为可以测度的信息;随着大数据大模型的发展,科学计量学迅速融入其中,逐渐兴起的计算社会学正在将更广泛的科学相关信息纳入其中,对于将复杂的科学清晰化是有很大积极意义的;然而,作为科学学的定量研究方法,科学计量学仍然要纳入到科学学支撑的科技政策框架当中,因而必须考虑到工具理性和价值理性的统一,而这就要求对科学计量学的发展更加要关注多源数据基础设施建设、本体论和方法论的统一,不能脱离科学社会学、科技史、科技哲学、科技政策等质性研究的阐释和分析。 展开更多
关键词 科学计量学 科学学 跨学科研究范式 发展进路
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成纤维生长因子受体1通过控制微小RNA let-7b表达调节内皮细胞线粒体生源的作用研究 被引量:2
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作者 胡琼英 杨矫 +1 位作者 陈高莉 陈秋 《中华内分泌代谢杂志》 CAS CSCD 北大核心 2018年第5期404-409,共6页
目的探索成纤维生长因子受体l(fihrohlast growth factor receptor1,FGFRl)在调控内皮稳态时对上游分子N-乙酰基-丝氨酰-天冬氨酰-赖氨酰-脯氨酸(N-acetyl-seryl-aspartyl-lysyl-proline、AcSDKP)的影响和下游微小RNAlet-7(microR... 目的探索成纤维生长因子受体l(fihrohlast growth factor receptor1,FGFRl)在调控内皮稳态时对上游分子N-乙酰基-丝氨酰-天冬氨酰-赖氨酰-脯氨酸(N-acetyl-seryl-aspartyl-lysyl-proline、AcSDKP)的影响和下游微小RNAlet-7(microRNA let-7、miR let-7)的诱导作用及与内皮细胞线粒体生源的关系,以期最终研究FGFR1在内皮稳态中的调控作用。方法下调FGF/FGFRl信号通路,蛋白质印迹(Western印迹.WB)法和细胞免疫荧光(Immunofluorescence staining)技术检测线粒体融合蛋白MFN2(mitofusin-2)、OPA1(optic atrophy protein1)和分裂蛋白DRP1(dynamin-related protein-1)的表达;应用线粒体染色(MitoTraker Green)检测线粒体的生成;运用实时荧光定量核酸扩增(Real-time Quantitative PCR、qPCR)检测技术检测microRNA let-7的表达。结果FGFRl通过诱导microRNA let-7b一5p的生成促进AcSDKP维持线粒体的生源;AcSDKP修复细胞因子复合物Triple(TGF-β2、IL-1β和TNF-α)所引起microRNA let-7b-5p表达抑制与线粒体的生成密切相关;抑制microRNA let-7b-5p的表达后,AcSDKP失去促进线粒体生成的作用:上调microRNA let-7b-5p的表达后,可修复内皮细胞中因FGF/FGFRl底物FRS2(fibroblast growth factor receptor substrate)沉默所致通路缺失所致的线粒体生成障碍。结论FGFRl通过上调microRNA let-7b-5p的表达,促进线粒体的生成,从而在内皮细胞的稳态中起着十分重要的作用。 展开更多
关键词 成纤维生长因子受体1 成纤维生长因子受体底物2 线粒体生源 微小RNA let-7b-5p
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基于t-SNE降维的科学基金资助项目可视化方法研究 被引量:17
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作者 陈挺 李国鹏 王小梅 《数据分析与知识发现》 CSSCI CSCD 北大核心 2018年第8期1-9,共9页
【目的】设计主题模型结合流形学习文本特征降维可视化方案,更有效地发现与更直观地展示科研基金资助布局。【方法】基于美国NSF信息与智能系统(IIS)10年(2008–2017)的基金资助项目数据,利用聚类算法结合人工判读构建项目主题标签;利用... 【目的】设计主题模型结合流形学习文本特征降维可视化方案,更有效地发现与更直观地展示科研基金资助布局。【方法】基于美国NSF信息与智能系统(IIS)10年(2008–2017)的基金资助项目数据,利用聚类算法结合人工判读构建项目主题标签;利用TF-IDF向量空间模型与LSA潜在语义分析主题模型分别构建项目申请书高维特征,采用流形学习中t-SNE非线性降维算法将高维特征映射到二维或三维空间中可视化展示;基于构建的项目主题标签结合人工判读检验可视化效果。【结果】实验结果表明,t-SNE算法结合潜在语义分析模型在实验数据降维效果明显,可视化图谱不论在二维还是三维空间中,相同主题项目有较好的聚集性,主题间同样显示了清晰的轮廓和分界。【局限】算法参数的预设与调整需人工参与,未对不同资助机构的基金文本数据的适用性进行验证。【结论】该方法是可行的且可视化图谱能够直观地反映资助机构的资助布局,对科研管理与决策者审视宏观科研布局能够起到辅助作用。 展开更多
关键词 科学基金项目 科研布局 LSA t-SNE 可视化图谱
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碳量子点荧光法测定食品营养强化剂葡萄糖酸亚铁的含量
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作者 江书庆 信建豪 《化学研究与应用》 北大核心 2025年第4期1034-1038,共5页
采用水热反应法制备碳量子点溶液,以此作为荧光探针,建立了一种Fe^(3+)的检测方法,并用来测定食品营养强化剂葡萄糖酸亚铁的含量。结果表明,以三羟甲基氨基甲烷和甘氨酸为原料,制备得到的碳量子点溶液荧光效率为27.54%。Fe^(3+)溶液在... 采用水热反应法制备碳量子点溶液,以此作为荧光探针,建立了一种Fe^(3+)的检测方法,并用来测定食品营养强化剂葡萄糖酸亚铁的含量。结果表明,以三羟甲基氨基甲烷和甘氨酸为原料,制备得到的碳量子点溶液荧光效率为27.54%。Fe^(3+)溶液在反应温度20℃、pH 1.00、作用时间4min时对碳量子点溶液的荧光猝灭效果最佳,浓度在1.00×10^(-5)~7.50×10^(-4)mol·L^(-1)范围内,与荧光值ΔF呈现良好的线性关系(R=0.9982),用于测定食品营养强化剂葡萄糖酸亚铁,结果为98.4%,加标回收率在96.08%~102.4%范围内,检出限为6.72μmol·L^(-1)。该方法可实时、实地快速测定葡萄糖酸亚铁的含量。 展开更多
关键词 碳量子点 葡萄糖酸亚铁 荧光探针 测定方法
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基于SRCKF算法的锂离子电池荷电状态估计
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作者 肜瑶 张洋洋 吕运朋 《电池》 北大核心 2025年第2期273-278,共6页
为提高荷电状态(SOC)估计的精度,以磷酸铁锂锂离子电池为研究对象,在双极化等效电路模型的基础上,分析容积卡尔曼滤波器(CKF)的SOC估计过程。针对CKF算法发散的问题,采用平方根容积卡尔曼滤波(SRCKF)算法进行电池SOC估计。SRCKF算法通... 为提高荷电状态(SOC)估计的精度,以磷酸铁锂锂离子电池为研究对象,在双极化等效电路模型的基础上,分析容积卡尔曼滤波器(CKF)的SOC估计过程。针对CKF算法发散的问题,采用平方根容积卡尔曼滤波(SRCKF)算法进行电池SOC估计。SRCKF算法通过引入正交三角(QR)分解,误差协方差矩阵在计算过程中以平方根的形式传播,从而确保矩阵的正定和对称。与CKF算法对比发现,SRCKF算法的估计误差为2.0534×10-4 V,说明可以提高SOC估计的精度。 展开更多
关键词 磷酸铁锂锂离子电池 双极化模型 平方根容积卡尔曼滤波(SRCKF)算法 荷电状态(SOC)估计
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