检索结果-南通市图书馆

Machine learning-based grayscale analyses for lithofacies identification of the Shahejie formation, Bohai Bay Basin, China

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2025年第1期22卷 42-54页

作者： yu-Fan wang Shang Xu Fang Hao Hui-Min Liu Qin-hong Hu Ke-Lai Xi Dong Yang National Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Shengli Oilfield Branch Company SINOPEC

It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs. To address the problem of low resolution in logging curves, this study establishes a grayscale-phase model based on high-resolution grayscale curves using clustering analysis algorithms for shale lithofacies identification, working with the Shahejie Formation, Bohai Bay Basin, China. The grayscale phase is defined as the sum of absolute grayscale and relative amplitude as well as their features. The absolute grayscale is the absolute magnitude of the gray values and is utilized for evaluating the material composition(mineral composition + total organic carbon) of shale, while the relative amplitude is the difference between adjacent gray values and is used to identify the shale structure type. The research results show that the grayscale phase model can identify shale lithofacies well, and the accuracy and applicability of this model were verified by the fitting relationship between absolute grayscale and shale mineral composition, as well as corresponding relationships between relative amplitudes and laminae development in shales. Four lithofacies are identified in the target layer of the study area: massive mixed shale, laminated mixed shale, massive calcareous shale and laminated calcareous shale. This method can not only effectively characterize the material composition of shale, but also numerically characterize the development degree of shale laminae, and solve the problem that difficult to identify millimeter-scale laminae based on logging curves, which can provide technical support for shale lithofacies identification, sweet spot evaluation and prediction of complex continental lacustrine basins.

关键词： Shale Machine learning Absolute grayscale Relative amplitude Grayscale phase model Lithofacies identification

Dematiaceous hyphomycetes from soil in tropical primordial rain forest of Jianfengling, Hainan Province of China Ⅰ

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

菌物学报 2008年第1期27卷 29-38页

作者： ZHANG yue-Li ZHANG Tian-yu wang hong-Feng Department of Plant Pathology Shandong Agricultural University Tai ＇an 271018 China

A total of 66 isolates of soil dematiaceous hyphomycetes belonging to 28 species in 22 genera was found from 22 soil samples in tropical primordial rain forest of Jianfengling in Hainan Island. Among them, the genera Beltraniopsis, Domingoella and Phaeoisaria are recorded for the first time in China, while Acrophialophora fusispora, Beltraniopsis esenbeckiae, Domingoella asterinarum, Phaeoisaria clematidis and Stachybotrys nephrospora are new record species to China. Descriptions and illustrations are given based on Chinese isolates. Dried cultures and living cultures studied have been deposited in Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).

关键词：土壤真菌中国新种新记录生物学特征热带原始雨林海南暗色丝孢菌

A preliminary report on soil dematiaceous hyphomycetes from the three river gorge regions in eastern Tibet

在线全文

学校读者我要写书评

暂无评论

菌物学报 2008年第1期27卷 39-47页

作者： GENG yue-Hua ZHANG Tian-yu wang hong-Feng Department of Plant Pathology Shandong Agricultural University Tai ＇an 271018 China

A total of 47 isolates of soil dematiaceous hyphomycetes belonging to 29 species in 15 genera were found from the gorge regions of three rivers (the Jinsha River, the Nu River and the Lantsang River) in eastern Tibet. Most of the genera and species found are new for the regions. Among them Eladia tibetensis is a new species, and Scytalidium acidophilum and S. circinatum are new records to China. Latin description is given for the new species. Brief descriptions and illustrations of the new records are also given based on Chinese isolates. The other 26 species being previously known from China in several genera are also listed. Dried cultures and living cultures studied have been deposited in Herbarium of Shandong Agricultural University: Plant Pathology (HSAUP).

关键词：三江峡谷地带西藏土壤真菌中国新种新记录生物学特征暗色丝孢菌

Measurement of Optic Axis Direction Based on Interference Fringe Method

在线全文

学校读者我要写书评

暂无评论

Semiconductor Photonics and Technology 2006年第3期12卷 188-193页

作者： LI Wei-tao SHEN Wei-min wang yu-hong College of Optoelectronic ＆ Electrical Information Engineering Shanghai University of Science and Technology Shanghai 200093CHN Department of Optoelectronic Information Engineering China Jiliang University Hangzhou 310018 CHN

In order to conquer the defect in low precision and small range for measuring optic axial angle based on conoscopic interference method, interference fringe method is proposed. It is not the distance deviating from melatope but fringe numbers to decide optic axial angle. Fringe numbers are divided into integer portion and decimal fraction portion, the decimal fraction portion is calculated by non-linear interpolation method and integer portion is determined by the relative placement of interference fringes in the principal section. Extremum arithmetic of digit image is proposed and can be used to determine the interference fringes conveniently and precisely. After different niobate crystals were measured, the result shows that measurement range of optic axial angle is increased efficiently and measurement error is reduced to 0.1°.

关键词： Crystal optics Conoscopic interference pattern Uniaxial crystal CCD camera Optic axis

Precision storage lifetime measurements of highly charged heavy ions in the CSRe storage ring using a Schottky resonator

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2025年第1期36卷 150-160页

作者： Qian wang Xin-Liang Yan Guang-yu Zhu Shahab Sanjari Li-Jun Mao He Zhao yuri ALitvinov Rui-Jiu Chen Meng wang yu-Hu Zhang You-Jin yuan Jun-Xia Wu hong-Yang Jiao yue yu Zu-Yi Chen Yin-Fang Luo Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China GSI Helmholtzzentrum für Schwerionenforschung Planckstrasse 164291 DarmstadtGermany FH Aachen University of Applied Sciences Heinrich-Mussmann-Str.152428 JülichGermany

Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged *** to the nondestructive ion detection features of Schottky noise detectors,the number of stored ions in the ring is determined by the peak area in the measured revolution frequency *** of their intrinsic amplitude-frequency characteristic(AFC),Schottky detector systems exhibit varying sensitivities at different *** low-energy electron-cooled stored ions,a new method is developed to calibrate the AFC curve of the Schottky detector system of the Experimental Cooler Storage Ring(CSRe)storage ring located in Lanzhou,*** the amplitude-calibrated frequency spectrum,a notable refinement was observed in the precision of both the peak position and peak *** a result,the storage lifetimes of the electron-cooled fully ionized^(56)Fe^(26+)ions were determined with high precision at beam energies of 13.7 and 116.4 MeV/u,despite of frequency drifts during the *** electron cooling was turned off,the effective vacuum condition experienced by the 116.4 MeV/u^(56)Fe^(26+)ions was determined using amplitude-calibrated spectra,revealing a value of 2×10^(−10)mbar,which is consistent with vacuum gauge readings along the CSRe *** method reported herein will be adapted for the next-generation storage ring of the HIAF facility under construction in Huizhou,*** can also be adapted to other storage ring facilities worldwide to improve precision and enhance lifetime measurements using many ions in the ring.

关键词： Lifetime measurement Schottky mass spectrometry Sensitivity response Highly charged heavy ion Resonator UH vacuum Nondestructive diagnostics

Links between allergic rhinitis and asthma

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2006年第8期119卷 676-683页

作者： LI Jing wang hong-yu ZHANG Chun-qing SUN Bao-qing Zhong Nan-shan Guangzhou Institute of Respiratory Disease First Affiliated Hospital of Guangzhou Medical School Guangzhou 510120 China

AIlergic diseases of the airway, which include seasonal rhinitis, chronic perennial rhinitis and asthma, are recognized as inflammatory disorders of the airway mucosa, but differ in the location of the inflammatory reaction and clinical manifestations of the disease. Asthma and allergic rhinitis frequently coexist in the same patient and are thought to share common predisposing genetic factors which interact with the environmental influences. Both diseases have increased in prevalence over recent decades particularly in westernized countries. This increase has been largely attributed to environmental factors such as exposure to aerial pollutants and early life events, including the degree of exposure to infectious agents which might affect IgE production, since there has been insufficient time for a significant change in the gene pool.

关键词： allergic rhinitis asthma pathogenesis

基于D-S证据理论的灰色定权聚类综合后评价方法

在线全文

学校读者我要写书评

暂无评论

系统工程理论与实践 2009年第5期29卷 123-128页

作者：王育红党耀国南京航空航天大学经济与管理学院南京210016

结合灰色定权聚类评估模型和D-S证据理论对项目综合后评价方法进行研究.应用差异信息序列熵理论,根据指标所蕴含信息量的多少确定聚类指标的权重;根据所得到的灰色定权聚类系数矩阵并把该矩阵经过适当转换,把每一个聚类对象作为影响后... 详细信息

结合灰色定权聚类评估模型和D-S证据理论对项目综合后评价方法进行研究.应用差异信息序列熵理论,根据指标所蕴含信息量的多少确定聚类指标的权重;根据所得到的灰色定权聚类系数矩阵并把该矩阵经过适当转换,把每一个聚类对象作为影响后评价结果的一条证据,考虑到证据推理中零绝对化问题存在的可能性,给出了解决办法;利用Dempster合成法则,得到了辨识框架中各子集的信度函数,根据信度函数最大值确定项目综合后评价的结果.可以充分利用定权聚类中所得到各聚类对象所属灰类的信息,减少了直接使用聚类系数最大化方法确定评价对象所属灰类造成的信息损失,最后通过一个算例说明了该方法的实用性和有效性。

关键词：灰色聚类评估信息熵证据理论合成法则信息融合

极限荷载作用下临近基坑c-φ土地基的破坏模式

在线全文

学校读者我要写书评

暂无评论

岩土力学 2007年第8期28卷 1677-1681页

作者：王红雨杨敏宁夏大学土木与水利工程学院宁夏银川750021 同济大学地下建筑与工程系上海200092

与地面水平时地基土体的对称破坏模式不同,临近基坑(边坡)地基土体的破坏模式呈现明显的非对称性。利用FLAC-3D数值模拟技术,研究了在竖向极限荷载作用下临近基坑c-φ土地基不同工况时的破坏模式,得出了与***所假设的边坡附近无黏性土... 详细信息

与地面水平时地基土体的对称破坏模式不同,临近基坑(边坡)地基土体的破坏模式呈现明显的非对称性。利用FLAC-3D数值模拟技术,研究了在竖向极限荷载作用下临近基坑c-φ土地基不同工况时的破坏模式,得出了与***所假设的边坡附近无黏性土地基破坏模式相一致的结论。最后将数值模拟结果与大尺寸模型试验数据以及***的基于应力特征线法的非对称滑动破坏模式的地基承载力理论解进行了分析对比。结果表明,采用叠加计算方法得到的承载力系数Nγq偏于安全。

关键词：临近基坑 c-ψ土地基极限荷载破坏模式数值模拟

应用分层编码保障组播系统QoS的高效资源分配

在线全文

学校读者我要写书评

暂无评论

北京邮电大学学报 2014年第4期37卷 64-68页

作者：陈雷王洪玉中国刑事警察学院公安情报学系沈阳110035 大连理工大学信息与通信工程学院辽宁大连116024

在传统的组播策略中,系统总的吞吐量受限于组播组中最差用户的信道增益.为了克服组播系统吞吐量受限的问题,采用基于分层编码的组播策略.在保障组内每个用户的服务质量(QoS)的同时,提出了一个新颖的子载波和比特分配算法,来最大化整个... 详细信息

在传统的组播策略中,系统总的吞吐量受限于组播组中最差用户的信道增益.为了克服组播系统吞吐量受限的问题,采用基于分层编码的组播策略.在保障组内每个用户的服务质量(QoS)的同时,提出了一个新颖的子载波和比特分配算法,来最大化整个组播组的吞吐量.在下行的正交频分多址无线组播系统中,提出了最优资源分配算法.为了减少最优化算法的计算复杂度,提出了一个2阶段次优化算法.仿真结果显示,次优化算法的系统功效十分接近最优化算法.次优化算法要远远优于传统的组播策略,而且还要优于Tian等所提出的算法.

关键词：组播分层编码资源分配服务质量