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2024 OES China Ocean Acoustics, coA 2024

作者： Sibo, Li rui, Guo dianlun, Zhang Yujuan, Li Xiaoqian, Hou Shengfeng, Wang Science and Technology on Underwater Acoustic Laboratory/ Technology R&d Center Harbin Engineering University Haiying Enterprise Group Co. Ltd Wuxi Harbin China Technology R&d Center Haiying Enterprise Group Co. Ltd Wuxi China Science and Technology on Underwater Acoustic Laboratory Harbin Engineering University Harbin China

ISBN: (纸本)9798350340297

In active low-frequency and high-power sonar systems, target detection must overcome strong reverberation. Active sonar reverberation interference strongly fluctuates with distance and exhibits significant temporal and spatial variations. Active sonar reverberation is a typical nonstationary background. complex changes in reverberation directly affect the target detection performance of active sonar systems. The major difficulty associated with current detection algorithms lies in autonomous detection, particularly in terms of the adaptability of detection algorithms to complex background interference. Accurately performing dynamic background estimation, suppressing interference, controlling false alarms, and highlighting weak targets are the focus of object detection. This paper proposes an active sonar target detection method driven by a combination of data and models. The proposed method can achieve target detection under strong reverberation interference with low sidelobe false alarms and high robustness. © 2024 IEEE.

关键词： reverberation

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A new method for predicting the density of drilling fluid based on non-parametric regression under HTHP 8

A new method for predicting the density of drilling fluid ba...

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8th International conference on Electrical, Mechanical and computer engineering, ICEMCE 2024

作者： Zhou, Haiqiu Ye, Yuguang Cheng, Weiheng Gu, Yixin Guo, Qijun Zhou, Tuo Bahedaer Xiao, Yue Jiang, Fuhua Zhou, Shiying Cnpc Engineering Technology R and D Company Limited Beijing China China National Oil and Gas Exploration and Development Co. Ltd. Beijing China

ISBN: (纸本)9798331506230

Temperature and pressure are important factors affecting the density of drilling fluid. As exploration and development gradually progress to deep layers and deep waters, formation temperature and pressure are getting higher and higher. Ignoring the influence of temperature and pressure on the density of drilling fluid will lead to large deviations in drilling hydraulic calculations and increase the probability of accidents such as lost circulation and overflow. In this paper, the density change of a set of field oil-based drilling fluids is measured through laboratory experiments. The temperature range is 20-180°C, and the pressure range is 0.1 MPa-180 MPa. A high-temperature and high-pressure density prediction model for oil-based drilling fluids is established based on the weighted linear regression method. Based on the established model, the high-temperature and high-pressure density of the experimental drilling fluid is predicted. The results show that the prediction error is less than 5%, and the calculation accuracy is high, which can guide on-site operation and construction. © 2024 IEEE.

关键词： drilling fluids

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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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Analysis of Shielding Structure and Material of MVdC-Class Current Sensor for Securing Magnetic Field Immunity

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Transactions of the Korean Institute of Electrical Engineers 2025年第4期74卷 753-759页

作者： Cho, Juhee Kim, Suyong Lee, Seungjae Kim, Byungtaek Department of Electrical Engineering Kunsan National University Gunsan Korea Republic of Korean Electronics Technology Institute Gwangju Korea Republic of Dept. of R&D CTE TECH CO. LTD. Korea Republic of

The current sensor of medium voltage dC converter station is basically required to have accuracy and linearity, and it must be immunity to the severe electromagnetic environment in the converter station. This paper analyzed the shielding structure and shielding material to satisfy the magnetic field immunity of MVdC-class current sensors. In order to evaluate the shielding characteristics against external magnetic fields, the test conditions specified in KS C 9610-4-8, 9 were referenced. The magnetic field strength and magnetic flux density distribution inside the sensor part, which can affect the current measurement, were calculated through three-dimensional finite element analysis. The analysis results are expected to be useful reference data for shielding design of fluxgate type current sensors. © The Korean Institute of Electrical Engineers.

关键词： Magnetic shielding

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Study of the Bonding Strength of the First Interface of Cement Sheath Using Fbg technology

SSRN

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SSrN 2024年

作者： Cheng, Y.Q. Gou, X.L. Liu, L.M. Zhao, C.J. Wang, r. Xia, X.r. Lin, Y. Liu, S.Q. SINOPEC Research Institute of Safety Engineering Co. Ltd China CNPC Engineering Technology R&D Co. Ltd China

An important parameter in predicting the failure of cement sheath interface sealing integrity is the bonding strength of cement sheath interface. With oil and gas exploration and development focusing on deep and ultra deep layers, traditional methods for testing bonding strength cannot meet the needs of cement sheath interface sealing. Based on FBG technology, this study developed an in-situ method to quantify interface bonding strength between cement sheath, and the accuracy of the method was verified through theoretical calculations. Under different curing conditions, experimental research was conducted using this new method to determine the mechanical properties of cement sheath interface bonding. It has been shown in the experimental results that the humidity change during quantification not only affects the initial stress state of the cement sheath interface, but also affects the bonding performance of the cement sheath interface by up to 17-100%. As a result, traditional measurement methods may misestimate the sealing ability of the cement sheath interface. Additionally, increasing the curing temperature and reducing the Young's modulus are more conducive to improving the bonding characteristics of the cement sheath interface than increasing the curing time. In the case of cement slurry systems used on-site, a 48-hour waiting period is sufficient to ensure good bonding of the cement sheath interface. As a result, developing a cement slurry system that is resistant to high temperatures, has high strength and low-carbon mechanical properties can improve the sealing integrity of underground cement sheath. © 2024, The Authors. All rights reserved.

关键词： Nondestructive examination

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development of Automatic recognition and recording System for rig Jobs

Development of Automatic Recognition and Recording System fo...

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2022 IAdC/SPE International drilling conference and Exhibition, dC 2022

作者： Ge, Yunhua Zhang, Yanlong Ge, Su Mei, Yunyi Wang, Wenzhi Yong, Fengwei He, david Zhang, Josh Wang, Zhenyu Wang, Yuxin CNPC – Engineering Technology R&D Company Limited China CNPC – Research Institute of Petroleum E&D China Sinohan Science and Technology Ltd. China CNPC United States CNPC – Western Drilling Company China

ISBN: (纸本)9781613998427

Keeping a record of drilling process automatically in real time is a requisite for KPI studies and getting support from rOCs experts. There are five categories of technical data describing a well's drilling process, which are rig jobs in time sequence, job operational parameters, unit lithology by depth, wellbore configuration by depth and job appraisal respectively. Among them, the data of rig jobs in time sequence covers whole process of well construction and is collected manually via daily drilling reports or Shift forms with little data quality control and is easy to be filled by mistakes or omissions. The other four types of data are mainly collected via mud logger, MWd/LWd tools, wire-line logging tools, etc and mostly realized automatic recording with strict data quality controls. In order to solve the shortcomings of data collecting and recording of rig jobs in time sequence, an automatic recognition and recording system for rig jobs is developed. Previously, the team had tried to identify 25 common rig jobs such as on-bottom drilling, tripping-in, tripping-out, circulating, reaming, etc by developing a judgment algorithm based on real-time operating parameters from mud logger and is proved to be inaccuracy and incompleteness due to insufficient data resolutions and limited data points especially when drill string is out of hole. This time, the team takes advantages of video data from on-site surveillance cameras and develops an automatic recognition and recording system for rig jobs by integration of AI video recognition algorithm with previous method. The AI video recognition is realized by applying U-Net, Attentioned, GAN, etc. and the AI model trained by a mass of labeled data. Finally, the system is deployed in sync with Wellsite data Platform (WdP) and tested on line with real-time data from both cameras and mud logger. The online tests showed that the system could recognize various rig jobs from spud-in to end of well with correctness rate of more tha

关键词： Cameras

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UAV Small Target detection Algorithm Based on YOLOv8 Lightweight 7

UAV Small Target Detection Algorithm Based on YOLOv8 Lightwe...

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7th International conference on robotics, control and Automation engineering, rCAE 2024

作者： Tao, Xiaojun Zhao, Jixing Liu, Bingyou Zhang, dongxiang Anhui University of Engineering Dept. School of Electrical Engineering Wuhu China Dept. R&d Department Huaneng Chaohu Power Generation Co. Ltd ChaoHu China Anhui Tianbing Electronic Technology Co. Ltd. Dept. R&d Department Wuhu China

ISBN: (纸本)9798350355642

despite significant progress in the lightweight design of UAVs, the limited computational resources that can be carried, and the existence of small targets with small sizes, inconspicuous features, and susceptibility to background interference and occlusion, UAV small target detection is still challenging. To maintain a certain accuracy while significantly reducing the model size, the article proposes a small target detection algorithm based on the YOLOv8s network. Firstly, the C2f module in the Backbone part is replaced by the dynamicconv module, which introduces adaptive convolution kernel parameters to enhance the feature extraction capability while reducing the redundancy of parameters;secondly, the weighted bidirectional feature pyramid BiFPN is utilized as the Neck-end network, which operates its highly efficient feature fusion, redundancy-reducing connection and weighted feature fusion mechanisms to improves the model accuracy, reduces the number of parameters and computation in the convolution process;finally, the up-sampling method of the original model is replaced with CArAFE and the loss function is replaced with WIoU, which enhances the model's ability to extract features in small targets, and improves the mAP50% by 1.4% and reduces the model volume by 69.8% compared to the Visdrone2019 dataset. The experimental results show that the improved model can more accurately recognize small targets in aerial photography, and can greatly reduce the volume of the model while maintaining higher accuracy. © 2024 IEEE.

关键词： Aerial photography

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A novel reprocessable chloroprene rubber based on dynamic disulfide metathesis

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International Journal of Smart and Nano Materials 2024年第1期15卷 42-61页

作者： Jianliang Jiang Junxue Zhai Yanqing Chen dongqi Zhao Yakai Feng School of Chemical Engineering and Technology Collaborative Innovation Center of Chemical Science and Chemical Engineering(Tianjin)Tianjin UniversityTianjinChina R&D Department of China(Yangzhou) Material Handling Tech-Engineering LtdYangzhouChina Key Laboratory of Rubber Plastics of Ministry of Education/Shandong Province (QUsT)School of Polymer Science&EngineeringQingdao University of Science&TechnologyQingdaoChina R&D Department of Tianjin Joaboa Technology Co.Ltd TianjinP.R.China Frontiers Science Center for Synthetic Biology Tianjin UniversityTianjinChina Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjinChina

For sustainable application of chloroprene rubber(Cr),a new technology is developed by the vulcanization of Cr using 2,2'-dithiodipyridine(dPd)as a cross-linking agent with the repro-cessing performance owing to disulfde *** dPd was incorporated into Cr vulcanization,the Menschutkin reac-tion between allyl chloride group and pyridine group occurred with a maximum exothermic peak at 184°*** number of effective cross-linking bond at o.5 phr dPd vulcanizate was higher than that at high dPd *** vulcanizate showed high tensile strength(11.12 MPa)and elongation at break(1253±120%)owing to the exchangeable disulfide bond in the *** the catalysis of triphenylphosphine,the metathesis of disulfide compound was improved obviously,which endowed Cr/dPd vulcanizates with good recyclability *** cross-linkage maintains its stability at low temperature,thus ensuring the mechanical stability of Cr/dPd vulcanizate under the ambient *** and reprocessing of Cr/dPd vulcanizate can be conducted with common industrial rubber processing *** reprocessable chloroprene rubber could have potential appli-cation in Cr industry,also serve to significantly improve envir-onmental sustainability.

关键词： Chloroprene rubber reprocessable Menschutkin reaction disulfide

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Novel Approach to Stimulation design Optimization for Ultra-deep, 200°C Temperature Formations: A Case Study in Kunteyi Block

Novel Approach to Stimulation Design Optimization for Ultra-...

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2024 SPE Gas and Oil technology conference, GOTECH 2024

作者： Hou, Tengfei Lin, Hai Wu, Xi Wang, Xiaolu Li, Zhanchun Zhang, Shiling Feng, Shengli Zhang, Yang Liu, Yong Shang, Litao Bai, Haoli CNPC Engineering Technology R&D Company Ltd Beijing Beijing China Qinghai Oilfield Oil and Gas Technology Research Institute Dunhuang China Qinghai Oilfield Company Dunhuang China The Third Gas Production Plant of Qinghai Oilfield China

ISBN: (纸本)9781959025405

The kunteyi Block, a domestic gas field, poses unique challenges with its ultra-deep, 392°F high-temperature conditions. These extreme environments significantly challenge the safety and efficiency of well testing and stimulation. The block faces issues such as:1) difficulty in reservoir coring and low accuracy in mechanical parameter interpretation from conventional logging data;2) Challenges in fracture initiation under pressure constraints in ultra-deep (20,964 ft TVd), high-stress, high-angle wells;3) Lack of experience in fracturing operations for ultra-deep, high-angle wells at 392°F. This paper presents a design methodology and process tailored for ultra-deep, high-temperature, high-angle wells. It begins with cutting test technology for in-depth rock mechanics testing, followed by an innovative mechanical specific energy calculation method, factoring in actual drilling bit selection. This approach, combined with rock mechanics parameters, facilitates the identification of optimal cluster locations. Key construction parameters like inter-stage spacing, perforation cluster number and hole count, measure displacement, and fluid volume were further refined through three-dimensional fracture expansion modeling. Moreover, for a suspected aquifer 30 feet below the first section, a targeted low-displacement, small-scale acidification process was implemented. The results demonstrate that this method effectively quantifies the rock mechanical parameters of the Kunteyi Block. The optimized perforation locations achieved lower breakdown pressures of 13,778 psi;an 8.5% reduction compared to neighboring wells at 15,055 psi. The high-angle wells, segmented into four stages with differentiated fluid scales ranging from 56,504 to 63,566 cubic feet and a pump rate increase from 18.9 bpm to 62.9 bpm, enabled efficient fracture initiation. The implementation of small-displacement acidification effectively prevented communication with the water layer, thus enhancing the project'

关键词： rock mechanics

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Fabrication of Linear Polarization-Separating Silicon Metalens at Long-Wavelength Infrared 1

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15th International conference on Sensing technology, ICST 2022

作者： Ishizuka, Noe Li, Jie Fuji, Wataru Ikezawa, Satoshi Iwami, Kentaro Department of Mechanical Systems Engineering Tokyo University of Agriculture and Technology Fuchu Japan Opto-Science R&D Department R&D Technology Center Tamron Co. Ltd. Saitama Japan

ISBN: (数字)9783031298714

ISBN: (纸本)9783031298707

A polarization-separating metalens at the long-wavelength infrared was designed, developed, and demonstrated. The silicon quadrangular pillars are adopted as meta-atoms to achieve full 2π phase coverage at the design wavelength of 10.6 μm for both of two orthogonal linear polarizations with high transmittance. Their dimensions were determined by electromagnetic field analysis based on a finite element method, and transmittances of more than 70% were obtained in all meta-atoms. The metalens was fabricated through electron beam lithography and reactive ion etching, and SEM observation showed that the fabrication was done while maintaining good verticality. An imaging test was performed using a commercially available micro-bolometer, and it was confirmed that the light was focused at different positions for each linear polarization. In the case of 45°-polarized illumination, it was confirmed that the light was focused at both locations. The fabricated metalens successfully showed the ability of linear polarization separation of a thermal image. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Silicon

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