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基于物联网技术的油田数字化建设

自动化应用 2024年第S01期65卷 467-469页

作者：曹治民大庆油田第三采油厂数字化运维中心黑龙江大庆163000

随着现代信息技术的发展,油田行业已面临转型发展的关键时期,将物联网技术应用于数字化油田建设中,为我国油田产业的转型提供了新的思路。依托物联网技术的数字化油田生产效率持续增长,对改变我国油田生产现状有积极意义。基于此,就当... 详细信息

随着现代信息技术的发展,油田行业已面临转型发展的关键时期,将物联网技术应用于数字化油田建设中,为我国油田产业的转型提供了新的思路。依托物联网技术的数字化油田生产效率持续增长,对改变我国油田生产现状有积极意义。基于此,就当代数字化油田建设中物联网技术的应用作出了深度分析,希望可以为我国油田数字化建设的进一步发展提供支持。

关键词：物联网油田数字化建设

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改进YOLOv8的PCB表面缺陷检测算法

电子测量技术 2024年第12期47卷 100-108页

作者：吕秀丽杨昕升曹志民东北石油大学物理与电子工程学院大庆163318

针对目前PCB表面缺陷检测方法存在复杂度过高、误检、漏检等问题,提出了一种改进YOLOv8的轻量型检测算法。由于YOLOv8主干网络下采样后的特征图存在一定冗余,设计轻量级的多尺度混合卷积(MSMC),并结合C2f模块增强多尺度特征提取能力;在... 详细信息

针对目前PCB表面缺陷检测方法存在复杂度过高、误检、漏检等问题,提出了一种改进YOLOv8的轻量型检测算法。由于YOLOv8主干网络下采样后的特征图存在一定冗余,设计轻量级的多尺度混合卷积(MSMC),并结合C2f模块增强多尺度特征提取能力;在颈部网络中设计改进的双向特征金字塔结构(BiFPN),使用两个跨层连接得到更加丰富的语义信息;使用C2f-Faster模块减少特征融合过程中的运算量;引入CA注意力机制与WIoUv2损失函数,增强对PCB小目标缺陷的定位能力。实验结果表明,相较于YOLOv8n,改进后的算法在PCB数据集上检测精度提高了2.2%,模型参数量和计算量降低了36.7%和18.5%,分别为1.9 M和6.6 G。最终模型大小仅为3.8 MB,为移动终端设备部署提供了新思路。

关键词：表面缺陷检测 YOLOv8 轻量化多尺度特征小目标缺陷

Effective DOA Estimation Under Low Signal-to-Noise Ratio Based on Multi-Source Information Meta Fusion

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Journal of Beijing Institute of Technology 2021年第4期30卷 377-396页

作者： Yun Wu Xiukun Li zhimin cao Acoustic Science and Technology Laboratory and the College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechniqueHarbin 150001China School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318HeilongjiangChina

Efficiently performing high-resolution direction of arrival(DOA)estimation under low signal-to-noise ratio(SNR)conditions has always been a challenge task in the ***-ously,in order to address this problem,the key is how to mine or reveal as much DOA related in-formation as possible from the degraded array ***,it is certain that there is no per-fect solution for low SNR DOA estimation designed in the way of ***,this paper proposes to explore in depth the complementary DOA related information that exists in spa-tial spectrums acquired by different basic DOA ***,these basic spatial spec-trums are employed as the input of multi-source information fusion *** the multi-source in-formation fusion model is composed of three heterogeneous meta learning machines,namely neural networks(NN),support vector machine(SVM),and random forests(RF).The final meta-spec-trum can be obtained by performing a final decision-making *** results illus-trate that the proposed information fusion based DOA estimation method can really make full use of the complementary information in the spatial spectrums obtained by different basic DOA *** under low SNR conditions,promising DOA estimation performance can be achieved.

关键词： direction of arrival(DOA) signal-to-noise ratio(SNR) information fusion meta-learn-ing spatial spectrum

西南印度洋中脊东段MORB微量元素地球化学及其对地幔源区组成的指示

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海洋地质与第四纪地质 2024年第4期44卷 99-107,I0001-I0003页

作者：董振梁锦曹志敏贺惠忠陈亮陆茸中国海洋大学海洋地球科学学院青岛266100 自然资源部南海调查中心海洋环境探测技术与应用重点实验室广州510275 自然资源部第二海洋研究所海底科学重点实验室杭州310012

西南印度洋中脊东段(E-SWIR)处于61°~70°E区域,具有相对匮乏的熔体供给。该区产出的大多数洋中脊玄武岩(MORB)具有富集不相容元素以及大离子亲石元素等特征,属典型E-MORB。基于玄武岩样品的微量元素地球化学资料,通过La/Sm、Zr/Nb和Lu... 详细信息

西南印度洋中脊东段(E-SWIR)处于61°~70°E区域,具有相对匮乏的熔体供给。该区产出的大多数洋中脊玄武岩(MORB)具有富集不相容元素以及大离子亲石元素等特征,属典型E-MORB。基于玄武岩样品的微量元素地球化学资料,通过La/Sm、Zr/Nb和Lu/Tb等分析表明E-SWIR地幔具有明显的不均一性,这种不均一性可能与地幔中辉石岩含量的沿轴变化有关。利用稀土元素Ce、Sm、Lu和Yb含量结合部分熔融计算模拟结果,进一步阐明地幔源区中石榴石的作用与影响,并且认为其可能是以含金红石榴辉岩的形式赋存于地幔之中。对E-SWIR地幔源区榴辉岩性质和赋存形式的识别是探讨EMORB成因、地幔不均一性与洋中脊构造演化等科学问题的关键。

关键词：元素地球化学地幔源区组成洋中脊玄武岩西南印度洋中脊东段

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面向目标机动类型的数据标签生成方法

指挥控制与仿真 2024年第3期46卷 86-94页

作者：汪其林曹志敏高静江苏自动化研究所江苏连云港222061

针对现有目标机动类型识别方法通用性不足、准确率较低等问题,提出基于改进K-medoids聚类的多层标签生成方法。以空中目标机动轨迹为例,设计多种数据预处理方法,采用动态时间规整作为聚类算法的距离度量,通过构建标签框架指导算法实施过... 详细信息

针对现有目标机动类型识别方法通用性不足、准确率较低等问题,提出基于改进K-medoids聚类的多层标签生成方法。以空中目标机动轨迹为例,设计多种数据预处理方法,采用动态时间规整作为聚类算法的距离度量,通过构建标签框架指导算法实施过程,进行迭代聚类以生成多层标签。在公开数据集上测试算法,实验结果表明,该方法在无监督情况下对第一层标签的识别准确率达到89.75%,接近传统有监督算法;同时,相对于没有引入标签框架的情况,能更有效地区分第二层模糊标签。该方法只需少量专家知识,便能简单地扩展到不同领域、不同机动类型。

关键词：标签生成动态时间规整 K-medoids聚类

Rare earth element geochemistry of hydrothermal deposits from Southwest Indian Ridge

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Acta Oceanologica Sinica 2012年第2期31卷 62-69页

作者： cao zhimin cao Hong TAO Chunhui LI Jun YU Zenghui SHU Liping Key Laboratory of Submarine Geosciences and Technology Ministry of EducationDepartment of Marine GeoscienceOcean University of ChinaQingdao 266100China Key Laboratory of Marine Hydrocaobon Resources and Environment Geology MLR Qingdao Institute of Marine GeologyQingdao 266071China Laboratory of Submarine GeoScience Second Institute OceanographyState OceanicAdministrationHangzhou 310012China Petrology of the Oceanic Crust Geosciences DepartmentUniversity of BremenBremen 28359Germany

The REE compositions of hydrothermal deposits and basalt samples from the Southwest Indian Ridge （SWIR） were determined with ICP-MS. The results show that there are significant differences between different types of samples although all samples show relative LREE enrichment. The contents of REE in hydrothermal sulfides and alterated rocks samples are lower （from 7.036× 10^-6 to 23.660×10^-6）, while those in the white chimney deposits are relatively higher （ranging from 84.496 × 10^-6 to 103.511 × 10^- 6）. Both of them are lower than basalts. Chondrite-normalized REE distribution patterns show that sulfides and alterated rocks samples are characterized by significant positive Eu anomalies. On the contrary, white chimney deposits have obvious negative Eu anomalies, which may be caused by abundant calcite existing in the white chimney samples. Both the content and distribution pattern of REE in sulfides suggest that REE most possibly is originally derived from hydrothermal fluids, but influenced by the submarine reducing ore-forming environment, seawater convection, mineral compositions as well as the constraint of mineral crystallizations.

关键词： rare earth element hydrothermal deposits Southwest Indian Ridge

Characteristics of platinum-group elements in basalts from spreading axis of Mariana Trough

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Acta Oceanologica Sinica 2007年第4期26卷 63-71页

作者： cao zhimin ZHENG Jianbin ZHOU Meifu AN Wei QI Liang College of Marine Geosciences Ocean University of China Qingdao 266003 China China Offshore Environmental Service Ltd Tanggu 300452 China Department of Earth Sciences University of Hong Kong Hong Kong 999077 China

Total platinum-group elements （PGEs） abundances in basalts from the spreading axis of Mariana Trough ranged from 0.418 × 10^9 to 1. 022 × 10^-9, and primitive mantle-normalized PGE patterns are of positive slope showing the relative enrichment of PPGE （ platinum, palladium, rhodium） and gold relative to IPGE. Compared with other mantle-originated rocks, these basalts have lower PGE contents and wider ranges of primitive mantle-normalized ratios of palladium content to iridium one, palladium content to platinum one and palladium content to gold one exhibiting relative platinum and iridium depletion. Characteristics of PGE patterns indicated that the studied Mariana Trough basalts originated from low partial melting, and the MORB mantle beneath the spreading center had been contaminated by the are-island mantle. In the aspect of trace elements, Mariana Trough basalts showed the enrichment of LILE, lead and LREE, indicating that they had been influenced by subduetion compositions. All these demonstrated that Mariana Trough basalts are products of partial melting from a mixed mantle （ the contamination of MORB mantle by are-island mantle）.

关键词： back-arc basin basalt platinum-group elements negative platinum anomaly subduction zone basin evolution

Coral Ba/Ca and Mn/Ca Ratios as Proxies of Precipitation and Terrestrial Input at the Eastern Offshore Area of Hainan Island

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Journal of Ocean University of China 2017年第6期16卷 1072-1080页

作者： JIANG Qiaowen cao zhimin WANG Daoru LI Yuanchao WU Zhongjie NI Jianyu School of Marine Geosciences Ocean University of China Qingdao 266100 P. R. China Second Institute of Oceanography State Ocean Administration Hangzhou 310012 P. R. China Hainan Academy of Ocean and Fisheries Sciences Haikou 570125 P. R. China

Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set(1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island(19?12'28.4''N, 110?37'38.8''E) were analyzed using inductively coupled plasma-optic emission spectrometry(ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol^(-1) in 1903 to a maximum of 10.064 μmol mol^(-1) in 1944, with an average of 5.256 μmol mol^(-1). Mn/Ca ratios varied from 0.206 to 5.708 μmol mol^(-1) with an annual average of 1.234 μmol mol^(-1), with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future.

关键词： Porites lutea eastern offshore area of Hainan Island Ba/Ca and Mn/Ca ratios terrigenous input precipitation climate proxy records

Simulation experiments on gas production from hydrate-bearing sediments

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Science China Earth Sciences 2009年第1期52卷 22-28页

作者： GONG JianMing cao zhimin CHEN JianWen ZHANG Min LI Jin YANG GuiFang College of Marine Geosciences Ocean University of ChinaQingdao 266003China Qingdao Institute of Marine Geology Qingdao 266071China Geochemical Department Yangtze UniversityJingzhou 434023China Langfang Branch Research Institute of Petroleum Exploration&DevelopmentPetroChinaLangfang 065007China

Experiments were made on 58 sediment samples from four sites (1244, 1245, 1250 and 1251) of ODP204 at five temperature points (25, 35, 45, 55 and 65°C) to simulate methane production from hydrate-bearing sediments. Simulation results from site 1244 show that the gas components consist mainly of methane and carbon dioxide, and heavy hydrocarbons more than C2 + cannot be detected. This site also gives results, similar to those from the other three, that the methane production is controlled by experimental temperatures, generally reaching the maximum gas yields per gram sediment or TOC under lower temperatures (25 and 35°C). In other words, the methane amount could be related to the buried depth of sediments, given the close relation between the depth and temperature. Sediments less than 1200 m below seafloor are inferred to still act as a biogenic gas producer to pour methane into the present hydrate zone, while sedimentary layers more than 1200 m below seafloor have become too biogenically exhausted to offer any biogas, but instead they produce thermogenic gas to give additional supply to the hydrate formation in the study area.

关键词： gas production simulation experiment hydrate-bearing sediments ODP204