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13th International Field Exploration and development Conference, IFEdC 2023

作者： Li, Yan-Chao Wang, Yi-Xuan Feng, Qiang Zou, Long-Qing Wen, Huan Gao, Xiang Shale Gas Exploration and Development Department CNPC Chuanqing Drilling Engineering Co. Ltd. Beijing China CNPC Engineering Technology R&D Company Ltd. Beijing China

ISBN: (纸本)9789819702596

To understand the sealing characteristics of temporary plugging agents (TPA) in the borehole, a system was established for simulating high pressure temporary plugging experiments. The influence of the type and the concentration of TPA, the carrying liquid viscosity and the pump displacement on the sealing characteristics are studied, and the comparison and selection experiments of TPA are also performed. It can be concluded from experimental results that i) the higher viscosity of carrying liquid leads more TPA to going into the low-angle-borehole, resulting in better sealing characteristic;ii) the larger pump displacement causes more boreholes blocked by the TPA (especially the number of blocked low-angle-boreholes are more than that of blocked high-angle-boreholes);iii) both low-angle-borehole and high-angle-borehole are filled with more TPA duo to the higher concentration of TPA;iv) the sealing efficiency of TPA-knot is the highest, followed by TPA-particle and TPA-ball, and the TPA-fiber is the lowest. For obtaining the excellent sealing efficiency, it is recommended the mixed use of TPA-knot, TPA-particle and TPA-ball. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Boreholes

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Scheme design of annular pressure control by rupture disk technology 34th

Scheme design of annular pressure control by rupture disk te...

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34th International Ocean and Polar Engineering Conference, ISOPE 2024

作者： Wang, Gang Lv, Shengming Xiang, Ying Liu, Yuhan Ye, Yu Ji, Fei Zhou, Tuo Jiang, Quanyu Cao, Jinyan CNPC Engineering Technology R&D Company Limited Beijing China China National Oil and Gas Exploration and Development Company Ltd Beijing China China University of Petroleum in Beijing Beijing China

ISBN: (纸本)9781880653784

deepwater oil and gas wells experience elevated wellbore temperatures during exploratory well testing and production well production, which generate expansion pressure and the phenomenon of elevated annulus pressure (APB). The annulus annulus pressure may trigger risks such as casing body damage, casing buckle leakage, etc., destroying the wellbore integrity of deepwater wells and posing serious safety risks to deepwater wellbore integrity. Therefore, deepwater oil and gas wells must adopt an annulus pressure management program. According to the engineering application experience, the rupture disk casing tool is a low-cost annulus pressure solution that is currently effective and widely used. In this paper, we study the pressure specification design of rupture disk to meet the requirement of annular pressure management in deepwater wells, and carry out the program design of rupture disk technology to control the annular pressure. When the annulus closure pressure exceeds the design threshold, the annulus high-pressure fluid overflows from the rupture disk, and the annulus closure pressure decreases, thus solving the problem of high annulus pressure. © 2024 by the International Society of Offshore and Polar Engineers (ISOPE).

关键词： rupture disks

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Investigation of Physiologically Interpretable deep Neural Network Using Pulse rate Variability in Mental Fatigue recognition

Investigation of Physiologically Interpretable Deep Neural N...

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International Conference on Affective Computing and Intelligent Interaction Workshops and demos (ACIIW)

作者： Yasuhide Hyodo Kiyoshi Yoshikawa Tomoya Ikuta Yota Komoriya Human Technology R&D Department Technology Development Laboratories Sony Corporation Tokyo Japan

ISBN: (数字)9798331516451

ISBN: (纸本)9798331516468

Mental fatigue recognition by heart rate variability analysis in a photoplethysmography (PPG) device in terms of pulse rate variability (PrV) is gathering interest for stress relief and well-being applications. To realize mental fatigue recognition systems, many studies have been conducted, which showed the high accuracy of such systems evaluations. However, there are limitations in generalization due to the lack of consideration of the physiological mechanism. In this study, we developed a framework for investigating mental fatigue recognition using physiologically interpretable deep neural network (dNN) in a wrist-worn PPG device. Furthermore, we developed a novel feature extraction method that captures the temporal accumulation of arousal states to consider the perspective of cognitive resource consumption. The results suggest that the method we developed improved the mental fatigue recognition performance of the wrist-worn PPG device throughout our experiments (an accuracy of 0.90 and an F1 score of 0.91). In addition, it was observed that the method for the wrist-worn PPG device enhanced the contribution of HrV indices, known to be associated with cognitive function. The findings demonstrate that the proposed approach enhances not only accuracy but also the physiological interpretability of the model in PPG devices.

关键词： Performance evaluation Accuracy Time series analysis Artificial neural networks Human factors Fatigue Photoplethysmography Feature extraction Physiology Heart rate variability

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The effect of minor addition of Mn in AA7075 Al–Zn–Mg–Cu aluminum alloys on microstructural evolution and mechanical properties in warm forming and paint baking processes

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International Journal of Lightweight materials and Manufacture 2023年第4期6卷 521-533页

作者： Tai, Cheng-Ling Pua, Yo-Ming Chung, Tsai-Fu Yang, Yo-Lun Chen, Hsueh-ren Chen, Chih-Yuan Wang, Shing-Hoa Yu, Chung-Yi Yang, Jer-ren Department of Materials Science and Engineering National Taiwan University Taiwan Taipei China Department of Mechanical Engineering National Taipei University of Technology Taiwan Taipei China Graduate Institute of Intellectual Property National Taipei University of Technology Taiwan Taipei China Department of Mechanical Engineering National Taiwan Ocean University Taiwan Keelung China Aluminum Products R&D Section New Materials R&D Dept. China Steel Corp. Taiwan Kaohsiung81233 China

The microstructures and mechanical properties in the peak ageing condition, warm forming process, and paint baking process of two Al–Zn–Mg–Cu aluminum alloys, which possessed the same base compositions but different levels of Mn (0 and 0.24 wt%), have been investigated. The results show that Mn addition can hardly refine the grain size (around 20 μm) in AA7075 aluminum alloy in warm forming and paint baking processes. Mn-free and Mn-containing alloys subjected to all three processes possess nano-precipitates of nearly the same size, indicating that Mn addition does not influence the nano-precipitate evolution in the aluminum matrix. Energy-dispersive X-ray spectroscopy (EdS) mapping results of dispersoids show that dispersoids in Mn-bearing specimens are enriched in Mn and depleted in Zn and Mg. The Zn and Mg expelled from dispersoids in Mn-containing specimens into the aluminum matrix presumably formed Zn- and Mg-rich zones around the dispersoids, which improved the precipitate transformation reation from GPII to η′ phase at the boundaries between aluminum matrix and dispersoids. Although the solid solution strengthening effect triggered by Mn addition might be less effective because of the formation of dispersoids, the slight enhancement of ultimate tensile strength (UTS) in Mn-containing specimens rather than in Mn-free specimens in all states can be attributed to the formation of nano-precipitates around the dispersoids. © 2023 The Authors

关键词： High resolution transmission electron microscopy

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Crystallographically vacancy‐induced MOF nanosheet as rational single‐atom support for accelerating CO_(2) electroreduction to CO

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Carbon Energy 2024年第8期6卷 49-62页

作者： Jin Hyuk Cho Joonhee Ma Chaehyeon Lee Jin Wook Lim Youngho Kim Ho Yeon Jang Jaehyun Kim Myung‐gi Seo Youngheon Choi Youn Jeong Jang Sang Hyun Ahn Ho Won Jang Seoin Back Jong‐Lam Lee Soo Young Kim Department of Materials Science and Engineering Korea UniversitySeoulRepublic of Korea Department of Chemical and Biomolecular Engineering Sogang UniversitySeoulRepublic of Korea Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)PohangRepublic of Korea Department of Materials Science and Engineering Research Institute of Advanced MaterialsSeoul National UniversitySeoulRepublic of Korea Lotte Chemical R&D Center DaejeonRepublic of Korea Department of Chemical Engineering Hanyang UniversitySeoulRepublic of Korea School of Chemical Engineering and Material Science Chung‐Ang UniversitySeoulRepublic of Korea

To attain a circular carbon economy and resolve CO_(2) electroreduction technology obstacles,single‐atom catalysts(SACs)have emerged as a logical option for electrocatalysis because of their extraordinary catalytic *** SACs,metal–organic frameworks(MOFs)have been recognized as promising support materials because of their exceptional ability to prevent metal *** study shows that atomically dispersed Ni single atoms on a precisely engineered MOF nanosheet display a high Faradaic efficiency of approximately 100% for CO formation in H‐cell and three‐compartment microfluidic flow‐cell reactors and an excellent turnover frequency of 23,699 h^(−1),validating their intrinsic catalytic *** results suggest that crystallographic variations affect the abundant vacancy sites on the MOF nanosheets,which are linked to the evaporation of Zn‐containing organic linkers during ***,using X‐ray absorption spectroscopy and density functional theory calculations,a comprehensive investigation of the unsaturated atomic coordination environments and the underlying mechanism involving CO^(*) preadsorbed sites as initial states was possible and provided valuable insights.

关键词： 2‐dimensional material carbon dioxide reduction metal-organic frameworks single‐atom catalysts vacancy sites

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research on the driver fatigue early warning model of electric vehicles based on the fusion of EMG and ECG signals

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High technology Letters 2024年第4期30卷 333-343页

作者： rEN Bin LI Qibing ZHOU Qinyu LUO Wenfa Shanghai Key Laboratory of Intelligent Manufacturing and Robotics School of Mechatronic Engineering and AutomationShanghai UniversityShanghai 200444P.R.China Zhejiang Key Laboratory of Robotics and Intelligent Manufacturing Equipment Technology Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201P.R.China SAIC Motor R&D Innovation Headquarters SAIC Motor Corporation LimitedShanghai 201804P.R.China

Electric vehicles have been rapidly developing worldwide due to the use of new ***,at the same time,serious traffic accidents caused by driver fatigue in emergency situations have also drawn widespread *** lack of datasets in real vehicle test environments has always been a bottleneck in the research of driver fatigue in electric ***,this study establishes a dataset from real vehicle test,applies the Bayesian optimization support vector machine(BOA-SVM)algorithm to take features of electromyography(EMG)and electrocardiography(ECG)signals as input and develop an early warning model for driving fatigue ***,the driver’s EMG and ECG signals are collected through real vehicle testing experiments and then combined with the driver’s subjective fatigue evaluation scores to establish the ***,the study establishes a driver fatigue early warning model for emergency ***-domain and frequency-domain features are extracted from the EMG *** component analysis(PCA)is applied for dimensionality reduction of these *** experimental results show that based on the input of dimensionality reduced EMG features and ECG features,the BOA-SVM algorithm achieved an accuracy of 94.4%in classification.

关键词： driver fatigue early warning electromyography(EMG)signal electrocardiography(ECG)signal principal component analysis(PCA) support vector machine(SVM)

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65-3: Viewing Angle Control through Electrically-Induced Effective Out-of-Plane retardation differences in Automotive displays

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SId Symposium digest of Technical Papers 2024年第1期55卷 893-896页

作者： Tae-Hoon Choi Hyun Wook Lee Jin Uk Ha Department of Advanced Materials R&D Korea Automotive Technology Institute Cheonan Republic of Korea 31214

We report a method for controlling the viewing angle using twisted nematic liquid crystal (TN-LC) materials for automotive display applications. We achieved switching between normal and privacy modes with the change in viewing-angle-dependent retardation through the reorientation of the TN-LC molecules under crossed polarizers by applying a vertical electric field.

关键词： Automotive displays viewing angle control liquid crystals polarization optics light control film

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Functional ceramic support as an independent catalyst layer for direct liquid fuel solid oxide fuel cells

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Journal of Advanced Ceramics 2023年第3期12卷 474-486页

作者： Jie Luo Kai Zhao Jishi Zhao Jun Li Yihui Liu dongchu Chen Qing Xu Min Chen School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China Guangdong Key Laboratory for Hydrogen Energy Technologies Foshan UniversityFoshan 528000China Foshan Institute of Environment and Energy Technology Foshan 528000China R&D Center of Hydrogen Energy Standardization Yunfu 527300China Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

A porous ceramic support is designed as a multi-functional independent catalyst layer for solid oxide fuel cells(SOFCs)running on liquid hydrocarbon *** layer consists of a highly porous Ce_(0.9)Ca_(0.1)O_(2−δ)ceramic backbone and active NiMo catalysts,which could be integrated into the conventional Ni metal containing the anode for internal reforming of the hydrocarbon *** to conventional catalyst layers sintered on the anodes,this independent catalyst layer could be simply assembled on top of the anode without additional sintering,thereby avoiding the mismatch of the thermal expansion coefficient between the catalyst layer and the anode and improving stability of a single ***,a current collector layer could be inserted between the catalyst and the anode to enhance current collection efficiency and electrochemical performance of the single *** 750℃,the independent catalyst layer displays high activity towards the catalytic decomposition of methanol,and the single cell could achieve the maximum power density of 400–500 mW·cm^(−2)in dry ***,by employing the independent catalyst layer,the single cell offers additional in-situ catalyst regeneration capability under the methanol operation *** 10 mL·min−1 air into an anode channel for 5 min is found to be effective to burn out carbon species in the catalyst layer,which reduces the degradation rate of the cell voltage by orders of magnitude from 2.6 to 0.024 mV·h−1 during the operation of 360 h in dry *** results demonstrate the significance of the independent catalyst layer design for direct internal reforming methanol fuel cells.

关键词： independent catalyst layer NiMo-Ce_(0.9)Ca_(0.1)O_(2−δ)catalyst internal reforming methanol solid oxide fuel cell(SOFC)

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Effect of gas quenching rate on microstructure and hardness of SAE 1078 steel during austempering treatment 28

Effect of gas quenching rate on microstructure and hardness ...

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28th Congress of the International Federation for Heat Treatment and Surface Engineering, IFHTSE 2023

作者： Kwon, Gi-Hoon Park, Hyunjun Yeo, Kuk-Hyun Lee, Young-Kook Kim, Sang-Gweon Heat & Surface Technology R&D Group Korea Institute of Industrial Technology Siheung15014 Korea Republic of Department of Materials Science and Engineering Yonsei University Seoul03722 Korea Republic of

ISBN: (纸本)9781713889533

The patenting process is required to obtain the proper ductility and toughness of high carbon steel for subsequent cold forming by wire drawing or rolling. It is mainly used with lead media for patening treatment because the excellent heat transfer properties of lead achieve uniform temperature distribution. replacing this process with technology that eliminates the use of hazardous lead presents challenges. In this study, our goal is to investigate the relationship between microstructure changes and mechanical properties according to isothermal temperatures and cooling rates using garnet powder as an alternative to lead media. After the austenizing treatment, the microstructure, hardness and friction properties of patented specimens at three isothermal temperatures (460, 560, 660 °C) and three compressed air flow rates (10, 50, 100 l/min) were analyzed to examine the relationship between mechanical properties according to lamellar spacing in pearlite. As the isothermal temperature decreases or the air flow rate increases, not only the lamellar spacing of perlite decreases, but also the banite structure is formed, which improves the hardness and wear characteristics. © 2023 28th IFHTSE 2023 Congress. All rights reserved.

关键词： Wear resistance

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research on Cement Sheath Integrity Under High Temperature during In-Situ development for Shale Oil Well 28th

Research on Cement Sheath Integrity Under High Temperature D...

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28th International Conference on Computational and Experimental Engineering and Sciences, ICCES 2022

作者： Guo, Xueli Qi, Fengzhong Yu, Yongjin Jin, Jianzhou Guo, Yuchao Ji, Hongfei Cheng, Yongqin Zhao, Zhengyang CNPC Engineering Technology R&D Company Limited Beijing China Research Institute of Petroleum Exploration and Development Beijing China China University of Petroleum Beijing China

ISBN: (纸本)9783031020964

The temperature is as high as 500 °C at the bottom of shale oil wells during in-situ development. during shale oil production, the fluids with high temperature are transmitted to the wellhead, and the wellbore temperature will rise extremely, which greatly affects the cement sheath integrity. In this paper, the linear expansion coefficient of cement stone under the temperature of 500 ℃ were measured. Based on the experimental data and the field data of shale oil well, the stage finite element modeling method was adopted to establish a casing-cement-formation (CCF) model considering the temperature and pressure coupling. The results revealed that the linear expansion coefficient of cement stone decreases linearly with the increase of temperature. When the temperature was less than 250 ℃, the cement stone expanded. However, when the temperature exceeded 250 ℃, it shrank. The maximum shrinkage ratio can be 25 × 10–6/℃ for the temperature of 500 ℃. The circumferential stress of the inner wall of cement sheath first increased rapidly, then slowly decreased to be stable. The larger the cement stone shrink ratio was, the greater the circumferential stress was. The maximum circumferential stress can exceed 10 MPa for the shrink ratio of 25 × 10–6/℃. It can be concluded that the circumferential stress appears in a tensile state under high temperature conditions, which can easily lead to the failure of the cement sheath seal. The strength of the cement stone should be considered when designing the cement slurry property. In addition to the decay performance, the expansion of the cement stone should also be designed to ensure that the cement stone does not shrink when subjected to high temperature conditions. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Cements

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