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ArMA-CUPB Geothermal International conference 2019

作者： Chen, Zhaowei Huang, rui Zhou, Xiaojin Song, Yi Qing, Chun Yang, Yang CNPC Engineering Technology R&D Company Limited Beijing China PetroChina Southwest Oil and Gas Field Company Chengdu China Sichuan Changning Natural Gas Development Co. Ltd. Chengdu China

In Changning and Weiyuan shale gas blocks, casing deformation occurred in more than 30% of wells during hydraulic fracturing, which restricted the efficient development of shale gas in China. Ning 201-H1 was a typical well which experienced casing deformation. The characteristics of casing deformation, include deformation time, deformation position and deformation shape, were analyzed, and the results indicate that the casing deformation was caused by a small fault slip. Using Microseismic monitoring data and ant tracking data，the dip and inclination angles of small faults were identified, and the mechanical activity of the fault was analyzed based on the in-situ stress and treating pressure data. The results show that under the in-situ stress conditions and treating pressure, the fault is critically stressed and was activated during fracturing, which caused casing deformation. The characteristics of cementing quality data, fracturing curve and microseismic data were analyzed. due to poor cementing quality, the fracturing fluid may break through the gap between casing and formation during fracturing, intrude the fault and finally activate the fault. Therefore, in order to avoid casing deformation, it is recommended to improve cementing quality and avoid small faults. copyright © ArMA-CUPB Geothermal International conference *** rights reserved.

关键词： Hydraulic fracturing

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CAT: LoCalization and IdentificAtion Cascade detection Transformer for Open-World Object detection

CAT: LoCalization and IdentificAtion Cascade Detection Trans...

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conference on computer Vision and Pattern recognition (CVPr)

作者： Shuailei Ma Yuefeng Wang Ying Wei Jiaqi Fan Thomas H. Li Hongli Liu Fanbing Lv Northeast University Shenyang China Information Technology R&D Innovation Center of Peking University School of Electronic and Computer Engineering Peking University Shenzhen Graduate School Shenzhen China Changsha Hisense Intelligent System Research Institute Co. Ltd

Open-world object detection (OWOd), as a more general and challenging goal, requires the model trained from data on known objects to detect both known and unknown objects and incrementally learn to identify these unknown objects. The existing works which employ standard detection framework and fixed pseudo-labelling mechanism $(PLM)$ have the following problems: (i) The inclusion of detecting unknown objects substantially reduces the model's ability to detect known ones. (ii) The $PLM$ does not adequately utilize the priori knowledge of inputs. (iii) The fixed selection manner of $PLM$ cannot guarantee that the model is trained in the right direction. We observe that humans subconsciously prefer to focus on all foreground objects and then identify each one in detail, rather than localize and identify a single object simultaneously, for alleviating the confusion. This motivates us to propose a novel solution called CAT: LoCalization and IdentificAtion Cascade detection Transformer which decouples the detection process via the shared decoder in the cascade decoding way. In the meanwhile, we propose the self-adaptive pseudo-labelling mechanism which combines the model-driven with input-driven $PLM$ and self-adaptively generates robust pseudo-labels for unknown objects, significantly improving the ability of CAT to retrieve unknown objects. Experiments on two benchmarks, i.e., MS-coco and PASCAL VOC, show that our model outperforms the state-of-the-art methods. The code is publicly available at https://***/xiaomabufei/CAT.

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Superior corrosion resistance-dependent laser energy density in(coCrFeNi)95Nb5 high entropy alloy coating fabricated by laser cladding

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International Journal of Minerals,Metallurgy and Materials 2021年第5期28卷 888-897页

作者： Wen-rui Wang Wu Qi Xiao-li Zhang Xiao Yang Lu Xie dong-yue Li Yong-hua Xiang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Fluid Interaction with Material Ministry of EducationBeijing 100083China R&D management department China nuclear power technology research institute Co.Ltd.Shenzhen 518031China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Unit 92228 People’s Liberation ArmyBeijing 100072China

(coCrFeNi)95Nb5 high entropy alloy(HEA)coatings were successfully fabricated on a substrate of Q235 steel by laser cladding ***(coCrFeNi)95Nb5 HEA coatings possess excellent properties,particularly corrosion resistance,which is clearly superior to that of some typical bulk HEA and common engineering *** order to obtain appropriate laser cladding preparation process parameters,the effects of laser energy density on the microstructure,microhardness,and corrosion resistance of(coCrFeNi)95Nb5 HEA coating were closely *** showed that as the laser energy density increases,precipitation of the Laves phase in(coCrFeNi)95Nb5 HEA coating gradually decreases,and diffusion of the Fe element in the substrate intensifies,affecting the integrity of the(coCrFeNi)95Nb5 *** decreases the microhardness of(coCrFeNi)95Nb5 HEA ***,the relative content of Cr2O3,Cr(OH)3,and Nb2O5 in the surface passive film of the coating decreases with increasing energy density,causing corrosion resistance to *** study demonstrates the controllability of a high-performance HEA coating using laser cladding technology,which has significance for the laser cladding preparation of other coCrFeNi-system HEA coatings.

关键词： high entropy alloy coating laser cladding technology laser energy density corrosion resistance

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Near-field Channel Estimation for dynamic Metamaterial Antenna Systems

Near-field Channel Estimation for Dynamic Metamaterial Anten...

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International conference on computer and communications (ICCC)

作者： Shifei Wang Shuming Guo Zhiqing Tang Gangtao Han Lingfeng Shen School of Cyber Science and Engineering Zhengzhou University Zhengzhou CN National Digital Switching System Engineering & Technological R&D Center Zhengzhou CN School of Electrical and Information Engineering Zhengzhou University Zhengzhou CN China Information Technology Designing & Consulting Institute Co. Ltd. Beijing CN

The next generation of wireless technology, 6G, will likely incorporate advanced technologies such as extremely large-scale antenna arrays (ELAA) and millimeter wave (mmWave) communication. These cutting-edge features have the potential to revolutionize the way we communicate wirelessly, near-field communication (NFC) can not be ignored in future 6G mobile networks. compared to far-field communication, the waves that propagate in the near-field region have a spherical wavefront. By utilizing the time agile of dMA and the correlation between near-field guidance vectors, we propose a novel channel estimation algorithm. compared with the classic two-dimensional (2d) multiple signal classifier (MUSIC) algorithm, this algorithm effectively reduces computational complexity and ensures estimation accuracy. Simulation results show that the proposed channel estimation scheme achieves the expected results.

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Optimizing Parameters of Two-Stage Pdc Bit in deep Formation Applications

SSRN

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SSrN 2023年

作者： Chen, Zhenliang Shi, Huaizhong Zhao, Heqian Huang, Zhongwei He, Wenhao Chen, Han Yu, Chao Zhang, Bo State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum-Beijing Beijing102249 China CNPC Engineering Technology R&D Company Limited Beijing Petroleum Machinery Co. Ltd Beijing102206 China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of Petroleum-Beijing Beijing102249 China Department of Civil and Environmental Engineering University of Alberta EdmontonABT6G 2G7 Canada

Two-stage PdC (Polycrystalline diamond compact) bit is a special drilling bit consisting of a small-diameter pilot and a large-diameter reamer. The unique rock-breaking structure is designed to improve the drilling efficiency and reduce drilling costs in deep and abrasive formations. According to previous studies, the hydraulic structure of the two-stage PdC bit can significantly affect the drilling performance of removing cuttings near the bottom of the wellbore. Therefore, this research has proposed to achieve a high efficiency of cuttings removal by optimizing the hydraulic structure. In this paper, the flow field at the bottom of the well near the two-stage PdC bit (Φ171.45 mm pilot + Φ215.9 mm reamer) has been numerically studied using the finite element method. As shown in the analysis results, both the flow rate of the pilot and the flow rate ratio of the pilot to the reamer increase significantly with the increase of the area ratio of the pilot nozzles to the total nozzles. The numerical data supports that the cuttings can be removed effectively from the bottom of the wellbore when the area ratio is between 0.75 and 0.80. Moreover, the cuttings can be removed effectively from the bottom of the wellbore when the mud viscosity is about 10 mPa·s, the rate of penetration is between 4 and 8 m/h, the drill speed is 90rpm and the cuttings particle sizes is between 1 and 2 mm. Besides, increasing the pump rate can imporve the cutting-carrying efficiency through the wellbore bottom. Field test results indicate that the average penetration rate of the test interval is increased by 30% and the footage of the test interval is increased by over 40% compared to the adjacent interval of the same well. This study can provide guidance for the optimal design of the hydraulic structure of such two-stage PdC bits. © 2023, The Authors. All rights reserved.

关键词： reamers

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Missing data Imputation for Photovoltaic Station Based on Spatiotemporal Features

Missing Data Imputation for Photovoltaic Station Based on Sp...

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Energy Storage and conversion (ISESC), CPSS & IEEE International Symposium on

作者： Kangjia Zhou Feng Gao Yusen Zhang Zhenyu Hou Kaizhe Nie Tao Xu Hanzhi Wang Kai Xu School of Electrical Engineering Shandong University Jinan China School of Control Science and Engineering Shandong University Jinan China R&D Department Shandong University Electric Power Technology Co. Ltd Jinan China Operation Department Zhucheng power supply Bureau Shunwang power supply office Weifang City Weifang Shandong province China

ISBN: (数字)9798350380514

ISBN: (纸本)9798350380521

Accurate and complete data is essential for data-driven applications. However, data loss is inevitable in photovoltaic (PV) station due to the vulnerability of transmission networks. Traditional imputation methods relying solely on the temporal features of individual inverters fail to achieve high accuracy under drastic environmental changes. This paper proposes a spatiotemporal feature-based data imputation method for PV stations, incorporating both the temporal features of single inverters and the spatial features among multiple inverters. This approach significantly improves imputation accuracy and maintains precision under rapidly changing conditions. Experimental results validate the effectiveness and superiority of the proposed method.

关键词： Photovoltaic systems Accuracy Statistical analysis Propagation losses Inverters Imputation Spatiotemporal phenomena resilience Energy storage

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directed Electron Transport Induced Surface reconstruction of 2d Nife-Ldh/Stanene Heterojunction Catalysts for Efficient Oxygen Evolution

SSRN

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SSrN 2024年

作者： Lu, Ze Wang, Jingkun Zhang, Pengfei Guo, Wenhao Shen, Yongqing Liu, Peizhi Ji, Jianlong Zhao, Min Liang, Haojie Guo, Junjie Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education College of Materials Science and Engineering Taiyuan University of Technology Shanxi Taiyuan030024 China Aluminum-Magnesium Based New Material R&D Co. Ltd. Subsidiary of Xing Xian County Economic and Technological Development Zone Xing County Xi'An033600 China

As promising non-noble candidates for oxygen evolution reaction (OEr), NiFe-based layered double hydroxides (NiFe-LdH) has been proven to transform into its high-oxidation-state Ni/Fe oxyhydroxide, which act as the primary active sites. However, advancing the emergence of high-oxidation-state Ni/Fe oxyhydroxide during OEr process currently remains a challenge. Herein, a novel 2d NiFe-LdH/stanene p-n junction catalyst is achieved by inserting stanene between NiFe LdH and Ni foam. Time-dependent raman spectra and density functional theory calculations (dFT) confirm that stanene not only benefits for the construction of built-in electric field, but also serves as an electron absorber to induce a directed electron transport from Ni, Fe to Sn, which thus facilitates the surface reconstruction to form the catalytically active NiOOH. consequently, an ultralow OEr overpotential (230 mV) at 100 mA cm-2 is achieved, corresponding to a considerable decrease of 22.3 % and 42.1 % compared with the individual NiFe-LdH and stanene, respectively. © 2024, The Authors. All rights reserved.

关键词： density functional theory

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A Novel Seed Sorting device Utilizing Vertical Centrifugation and Spectroscopy Techniques

A Novel Seed Sorting Device Utilizing Vertical Centrifugatio...

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Innovations and development of Information Technologies and robotics (IdITr), International conference on

作者： Bijuan Chen Xuexian Chen Lin Wang Xiangbao Meng Nihong Liu Zheng Xiong Guangdong Institute of Modern Agricultural Equipment Guangzhou China Department of Electronic and Information Engineering Harbin Institute of Technology Shenzhen China Shenzhen Institute of Modern Agricultural Equipment Shenzhen China School of Electronic and Electrical Engineering Zhaoqing University Zhaoqing China Guangdong Hongke Agricultural Machinery R&D Co. Ltd. Guangzhou China

ISBN: (数字)9798350385694

ISBN: (纸本)9798350385700

The ever-increasing demands for high-yield, superior crops have led to a heightened need for high-quality seeds, thus driving the robust development of the global seed sorting machine market. This paper designs a new type of seed sorting equipment that adopts advanced technologies such as near-infrared spectroscopy. By utilizing a vertical centrifugation device, the equipment achieves high-throughput seeding, not only improving the efficiency of single grain seed sorting but also significantly enhancing seed detection accuracy. This equipment offers an efficient solution that is expected to provide a reference for high-throughput, high-precision seed sorting. Moreover, the versatility and high-performance of this device can aid in achieving long-term goals of increasing crop yields and reducing waste, thereby addressing the problem of high initial investment costs.

关键词： Technological innovation Accuracy Neural networks Seeds (agriculture) Object recognition Functional near-infrared spectroscopy Information technology

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design of a multi-channel fatigue test monitoring cloud platform based on the Internet of Things

Design of a multi-channel fatigue test monitoring cloud plat...

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International Symposium on computer Science and Intelligent controls (ISCSIC)

作者： Haoquan Qi Jianyu Zhao Lingling Sun Tong Cang Yanyu Li Xudong Wang School of Control Science & Engineering University of Jinan Jinan China Design Department DOCER Testing Technology Co. Ltd Jinan China R&D Department DOCER Testing Technology Co. Ltd Jinan China Electrical Department DOCER Testing Technology Co. Ltd Jinan China

The fatigue test, as an essential means widely used in fatigue life detection of machine components, is characterized by a long test cycle, large amounts of data, and many unexpected conditions, which leads to a heavy monitoring work of fatigue test. Given the above problems, this paper proposes a multi-channel fatigue test monitoring system based on IoT (Internet of Things) and cloud services. It develops a monitoring cloud platform based on the Java EE framework, HTTP, and WebSocket communication protocols to realize the management of test data and user equipment information as well as the visual monitoring of fatigue tests. It can also communicate with the system’s test server and Android client. On this basis, the cloud platform is trialed with other layers of hardware and software devices in the system. The test results show that the performance of the monitoring cloud platform is stable and sound, and the expected functional effects are achieved.

关键词： Cloud computing Technological innovation Operating systems Web pages computer architecture Fatigue real-time systems

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Study on Influence of Mechanical Parameters of Cement Plug on Sealing Integrity of Abandoned Wellbore

Study on Influence of Mechanical Parameters of Cement Plug o...

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作者： Jiang, Jiwei Li, Jun Nie, Jiejing Liu, Gonghui Huang, Tao Li, Wai China University of Petroleum-Beijing Beijing102249 China Beijing Petroleum Machinery Co. Ltd. CNPC Engineering Technology R&D Co. Ltd. Beijing102206 China The University of Western Australia CrawleyWA6009 Australia

With the continuous exploitation of oil and gas resources, more and more closed offshore oil and gas wells, no oil or gas showed wells and carbon dioxide wells which have no industrial value are facing disposal. Blocking and abandoning operations mainly involve sealing the wellbore through injecting cement plugs into appropriate layers in it preventing the form of fluid turbulence from crossflowing in the wellbore. The key guarantee of the sealing integrity of the wellbore is ensuring the cement plug in the wellbore can’t be destroyed. According to the basic theory of elastic-plastic mechanics, the cement plug-casing-cement sheath-formation combination model was established. The reliability of the model is verified through the utilizing of the finite element method to calculate the sealing capacity of cement plug under different pressure difference, which is consistent with Nagelhout’s experimental results. The effects of the elastic modulus, Poisson’s ratio and thermal expansion coefficient of the cement plug on the integrity of the cement plug seal were analyzed. The results show that the lower the elastic modulus, the lower the risk of cement plug failure;and the Poisson’s ratio has little effect on the cement plug integrity;when the thermal expansion coefficient of the cement plug is less than the thermal expansion coefficient of the stratum, the cement plug is prone to sealing failure;When The coefficient of thermal expansion is greater than the coefficient of thermal expansion of the stratum formation, the possibility of sealing failure of the cement plug is small. According to the construction conditions on site, properly reducing the elastic modulus of the cement plug, and trying to use cement plugs with large thermal expansion coefficient can help cut the possibility of cement plug sealing failure risk down. The established finite element model and the research results can provide reference for the design of cement plugs during the process of wellbore dispo

关键词： Elastic moduli

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