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鄂尔多斯盆地神木气田二叠系石千峰组5段致密气富集因素及有利区预测

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石油与天然气地质 2024年第3期45卷 739-751页

作者：吴伟涛冯炎松费世祥王一妃吴和源杨旭东西安石油大学地球科学与工程学院陕西西安710065 陕西省油气成藏地质学重点实验室陕西西安710065 中国石油长庆油田分公司勘探开发研究院陕西西安710029

针对致密砂岩气富集主控因素不清、有利区预测难度大的关键问题,以鄂尔多斯盆地神木气田二叠系石千峰组5段(千5段)为研究对象,利用地震、钻井、测井和测试分析资料,研究了致密气气藏特征,分析了断裂、储层、盖层、隔层、烃源岩和海拔条... 详细信息

针对致密砂岩气富集主控因素不清、有利区预测难度大的关键问题,以鄂尔多斯盆地神木气田二叠系石千峰组5段(千5段)为研究对象,利用地震、钻井、测井和测试分析资料,研究了致密气气藏特征,分析了断裂、储层、盖层、隔层、烃源岩和海拔条件对致密气富集的影响,预测了致密气勘探有利区。研究表明:千5段砂体为辫状河三角洲平原亚相分流河道砂体,继承性走滑断裂起到改善储层和输导天然气的作用。气层孔隙度为6.0%~12.0%,平均9.1%,渗透率为(0.20~0.80)×10^(-3)μm^(2),中值为0.49×10^(-3)μm^(2),气藏为透镜状致密气藏,具有横向连片、纵向叠置的准连续型分布特征。断裂和储层物性是致密气富集的主要因素,盖层厚度、隔层厚度和源岩煤层厚度的控气作用相对微弱,海拔条件对天然气分布不具有控制作用。当气井与断裂的距离大于9 km、储层泥质含量大于12%、隔层泥岩厚度大于210 m时,随着参数值的减小,天然气富集程度增强;当孔隙度小于9%、渗透率小于0.5×10^(-3)μm^(2)、盖层泥岩厚度小于120 m、源岩煤层厚度小于15 m时,随着参数值的增加,天然气富集程度增强。提出气层富集指数预测致密气藏有利区,优选出14个Ⅰ类有利区和22个Ⅱ类有利区,它们主要分布在神木气田东部。

关键词：富集因素有利区预测致密气石千峰组神木气田鄂尔多斯盆地

Integrating Manifold Knowledge for Global Entity Linking with Heterogeneous Graphs

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Data Intelligence 2022年第1期4卷 20-40页

作者： Zhibin Chen Yuting Wu yansong feng Dongyan Zhao Wangxuan Institute of Computer Technology Peking UniversityBeijing 100871China Center for Data Science Peking UniversityBeijing 100871China The MOE Key Laboratory of Computational Linguistics Peking UniversityBeijing 100871China

Entity Linking(EL)aims to automatically link the mentions in unstructured documents to corresponding entities in a knowledge base(KB),which has recently been dominated by global *** many global EL methods attempt to model the topical coherence among all linked entities,most of them failed in exploiting the correlations among manifold knowledge helpful for linking,such as the semantics of mentions and their candidates,the neighborhood information of candidate entities in KB and the fine-grained type information of *** we will show in the paper,interactions among these types of information are very useful for better characterizing the topic features of entities and more accurately estimating the topical coherence among all the referred entities within the same *** this paper,we present a novel HEterogeneous Graph-based Entity Linker(HEGEL)for global entity linking,which builds an informative heterogeneous graph for every document to collect various linking *** HEGEL utilizes a novel heterogeneous graph neural network(HGNN)to integrate the different types of manifold information and model the interactions among *** on the standard benchmark datasets demonstrate that HEGEL can well capture the global coherence and outperforms the prior state-of-the-art EL methods.

关键词： Entity linking Heterogeneous graph Graph neural network Entity disambiguation Knowledge base

Internal OH^(-)induced cascade quenching of upconversio n luminesce nee in NaYF4:Yb/Er nanocrystals

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Light(Science & Applications) 2021年第6期10卷 1078-1087页

作者： yansong feng Zhi Li Qiqing Li Jun Yuan Langping Tu Lixin Ning Hong Zhang van't Hoff Institute for Molecular Sciences University of AmsterdamScience Park 9041098XH AmsterdamThe Netherlands. State Key Laboratory of Explosion Science and Technology School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China. Anhui Key Laboratory of Optoelectronic Materials Science and Technology Department of PhysicsAnhui Normal University241000 WuhuChina. State Key Laboratory of Luminescenee and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033 JilinChina

Internal hydroxyl impurity is known as one of the main detrimental factors affecting the upconversion(UC)efficiency of upconversion luminescence(UCL)*** from surface"ligand-related emission quenching which can be effectively diminished by,e.g.,core"shell structure,internal hydroxyl is easy to be introduced in synthesis but difficult to be quantified and ***,it becomes an obstacle to fully understand the relevant UC mechanism and improve UC efficiency of *** we report a progress in quantifying and large-range adjustment of the internal hydroxyl impurity in NaYF4 *** combining the spectroscopy study and model simulation,we have quantitatively unraveled the microscopic in teractions underlying UCL que nching between internal hydroxyl and the sensitizers and activators,***,the internal hydroxyl-involved UC dynamical process is interpreted with a vivid concept of"Survivor effect" i.e.;the shorter the migration path of an excited state,the larger the possibility of its surviving from hydroxyl-induced quenchi *** from the consist ent experimental results,this concept can be further evidenced by Monte Carlo simulation,which monitors the variation of energy migration step distribution before and after the hydroxyl *** new quantitative insights shall promote the construction of highly efficient UC materials.

关键词： materials. quenching excited

Development of a semi-quantitative food frequency questionnaire for middle-aged inhabitants in the Chaoshan area, China

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World Journal of Gastroenterology 2005年第26期11卷 4078-4084页

作者： feng-yansong TakezakiToshiro KeLi PingYu Xu-KaiLin He-LinYang Xiao-LingDeng Yu-QiZhang Lai-WenLv Xin-EnHuang TajimaKazuo DepartmentofPreventiveMedicine ShantouMedicalUniversityShantou515041GuangdongProvinceChina DepartmentofInternationalIslandandCommunityMedicine KagoshimaUniversityGraduateSchoolofMedicalandDentalSciences8-35-1SakuragaokaKagoshima890-8544Japan ShantouDiseasePreventiveandControlCenter Shantou515031GuangdongProvinceChina theBoardofHealthNan'aoCounty Shantou515000GuangdongProvinceChina JiangsuProvinceCancerHospital Nanjing210009JiangsuProvinceChina DivisionofEpidemiologyandPrevention AichiCancerCenterResearchInstituteAichi464-8681NagoyaJapan

AIM:This paper aims to develop a data-based semi-quantitative food frequency questionnaire (SQFFQ) covering both urban and rural areas in the Chaoshan region of Guangdong Province, China, for the investigation of relationships between food intake and lifestyle-related diseases among middle-aged Chinese. METHODS: We recruited 417 subjects from the general population and performed an assessment of the diet, using a 3-d weighed dietary record survey. We employed contribution analysis (CA) and multiple regression analysis (MRA) to select food items covering up to a 90% contribution and a 0.90 R2, respectively. The total number of food items consumed was 523 (443 in the urban and 417 in the rural population) and the intake of 29 nutrients was calculated according to the actual consumption by foods/ recipes. RESULTS: The CA selected 233,194, and 183 foods/recipes for the combined, the urban and the rural areas, respectively, and then 196,157, and 160 were chosen by the MRA. Finally, 125 foods/recipes were selected for the final questionnaire. The frequencies were classified into eight categories and standard portion sizes were also calculated. CONCLUSION: For adoption of the area-specific SQFFQ, validity and reproducibility tests are now planned tc determine how the combined SQFFQ performs in actual assessment of disease risk and benefit.

关键词： Nutrients Weighed diet records Contribution analysis Multiple regression analysis

The Establishment of Teaching Mode of PBL in College English Extended Courses in Digital Context

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The Establishment of Teaching Mode of PBL in College English...

作者： yansong feng Foreign Language Department Xuzhou University of Technology

With the enhancement of the breadth and depth of China' involvement in the global governance, practical English-speaking talents with high qualities are in great need. The evolvement of the guiding line of college English teaching and the change of college English examination greatly propel the reform of English teaching mode. The application of PBL in college English extended courses conforms to the rule of cognitive development that college students are supposed to have. Students' overall qualities are spirally improved during the achievements of the project themes. Therefore, the application of PBL is an effective way of fostering practical talents.

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面向法律文书的自然语言理解

中文信息学报 2022年第8期36卷 1-11页

作者：安震威来雨轩冯岩松北京大学王选计算机研究所北京100871 国家开放大学计算机学院北京100039

法律人工智能因其高效、便捷的特点,近年来受到社会各界的广泛关注。法律文书是法律在社会生活中最常见的表现形式,应用自然语言理解方法智能地处理法律文书内容是一个重要的研究和应用方向。该文梳理与总结面向法律文书的自然语言理解... 详细信息

法律人工智能因其高效、便捷的特点,近年来受到社会各界的广泛关注。法律文书是法律在社会生活中最常见的表现形式,应用自然语言理解方法智能地处理法律文书内容是一个重要的研究和应用方向。该文梳理与总结面向法律文书的自然语言理解技术,首先介绍了五类面向法律文书的自然语言理解任务形式:法律文书信息提取、类案检索、司法问答、法律文书摘要和判决预测。然后,该文探讨了运用现有自然语言理解技术应对法律文书理解的主要挑战,指出需要解决好法律文书与日常生活语言之间的表述差异性、建模好法律文书中特有的推理与论辩结构,并且需要将法条、推理模式等法律知识融入自然语言理解模型。

关键词：法律人工智能自然语言理解综述

耕作模式对河西绿洲灌区夏玉米农田土壤呼吸的影响

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中国沙漠 2023年第4期43卷 200-208页

作者：冯彦淞杨彩红强玉泉甘肃农业大学林学院甘肃兰州730070

以河西绿洲灌区夏玉米农田土壤为研究对象,设置免耕(NT)和传统耕作(CT)两种耕作方式,玉米间作小麦(W/M)、玉米小麦轮作(W→M)和麦后插播冬油菜还田玉米轮作(W-G→M)3种种植模式,探讨河西绿洲灌区不同耕作模式对夏玉米农田土壤呼吸变化... 详细信息

以河西绿洲灌区夏玉米农田土壤为研究对象,设置免耕(NT)和传统耕作(CT)两种耕作方式,玉米间作小麦(W/M)、玉米小麦轮作(W→M)和麦后插播冬油菜还田玉米轮作(W-G→M)3种种植模式,探讨河西绿洲灌区不同耕作模式对夏玉米农田土壤呼吸变化特征的影响。测定夏玉米不同生育时期土壤呼吸速率、土壤温度和土壤含水量。结果表明:河西绿洲灌区不同耕作模式下夏玉米农田土壤呼吸有着明显的单峰型日变化,且峰值出现在15:00左右,玉米生育期峰值出现在拔节期(6月上旬)。土壤呼吸速率与土壤温度、土壤含水量均显著正相关,且土壤呼吸速率日变化主要受5 cm土壤温度影响。6种耕作模式的土壤呼吸的温度敏感性Q10值为1.60~2.70,免耕均高于传统耕作,且依次为NT W→M>NT W/M>NT W-G→M>CT W-G→M>CT W→M>CT W/M。河西绿洲灌区不同耕作模式下夏玉米农田土壤呼吸不仅受土壤温度影响,还受土壤含水量的影响。

关键词：河西绿洲灌区耕作方式夏玉米土壤呼吸

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基于弱监督学习的海量网络数据关系抽取

计算机研究与发展 2013年第9期50卷 1825-1835页

作者：陈立玮冯岩松赵东岩北京大学计算机科学技术研究所北京100871

在大数据时代,对于海量网络数据的信息抽取与应用已成为自然语言处理和信息检索技术发展的重要主题.其中,基于弱监督的关系抽取方法,因为具有不需要过多人工参与、适应性强的特点,受到了广泛的关注.目前针对它的研究主要集中在英语资源... 详细信息

在大数据时代,对于海量网络数据的信息抽取与应用已成为自然语言处理和信息检索技术发展的重要主题.其中,基于弱监督的关系抽取方法,因为具有不需要过多人工参与、适应性强的特点,受到了广泛的关注.目前针对它的研究主要集中在英语资源上,主要使用传统的词法和句法特征.然而,词法特征有严重的稀疏性问题,句法特征则对一些语言分析工具的性能有较强的依赖性.提出利用n-gram特征来缓解传统词法特征稀疏性的问题.特别地,这种特征还可以弥补传统句法特征在其他语言上不可靠的情况,对于关系抽取的跨语言应用有重要作用.在此基础上,针对弱监督学习中标注数据不完全可靠的情况,提出基于bootstrapping思想的协同训练方法来对弱监督关系抽取模型进行强化,并且对预测关系时的协同策略进行了详细分析.在大规模的中文和英文数据上进行实验的结果显示,把传统特征与n-gram特征相结合并进行协同训练,在中文和英文数据集上均可以提升弱监督关系抽取的效果,可以适应多语言的关系抽取需求.

关键词：关系抽取弱监督学习最大熵模型协同训练知识库构建

高三学生体育锻炼特点及其与高考成绩关系的实证研究

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教育学报 2024年第3期20卷 167-181页

作者：冯沁雪王严淞马莉萍南京大学教育研究院南京210023 北京体育大学教育学院北京100084 北京大学教育经济研究所北京100871

党和国家高度重视青少年身体健康与体育锻炼,出台各项政策保障青少年每天校内锻炼至少1小时,而面临高考压力的高三年级学生的体育锻炼时间很容易被学业挤占。基于某省2021届高三毕业生调查数据,使用统计分析、计量回归分析、倾向性得分... 详细信息

党和国家高度重视青少年身体健康与体育锻炼,出台各项政策保障青少年每天校内锻炼至少1小时,而面临高考压力的高三年级学生的体育锻炼时间很容易被学业挤占。基于某省2021届高三毕业生调查数据,使用统计分析、计量回归分析、倾向性得分匹配等方法,分析高三学生的体育锻炼情况及其与高考成绩的关系,发现近八成高三学生坚持每天锻炼1小时及以上,不足两成学生每天锻炼2小时及以上。其中,女生、独生子女、城镇户口、父母文化程度较高、中考成绩较好、优质高中的学生平均体育锻炼时长更短。参加体育锻炼的学生高考成绩显著高于未参加的学生,差异主要体现在女生、中考成绩较好、优质高中等本身较少参加体育锻炼的学生中。体育锻炼时长与高考成绩之间呈倒U型关系,每天锻炼1.1小时的学生高考成绩最优,女生、中考成绩排名靠前、优质高中学生的最优体育锻炼时长更长、高于其平均体育锻炼时长。以上发现侧面检验了相关政策的现实价值,并对明确高中学生体育锻炼要求、提高学生体育锻炼意识具有重要启示。

关键词：体育锻炼高考成绩高三学生倒U型函数理论