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International Conference on Information, Communication and Networks (ICICN)

作者： Zhe Li Jing Zhao Research and Development Department China Academy of Launch Vehicle Technology Beijing China

ISBN: (纸本)9781665490832

In order to solve the hidden terminal problem of SPMA protocol in multihop environment, this paper proposes a distributed load sensing method. The cross layer joint optimization design of network layer and link layer is adopted. The topology state perceived by network layer is used to correct the evaluation of the channel load rate in link layer, and then dynamically to adjust the priority threshold. The problem of inaccurate evaluation of SPMA channel load rate in multi-hop network environment is solved. And the message transmission success rate in multi-hop environment is improved. This paper establishes SPMA simulation scenario and improved algorithm model, then simulates and analyzes the application layer throughput, application layer end-to-end delivery rate, application layer end-to-end delay, link layer load, link layer throughput, link layer delivery rate, link layer queuing delay and other indicators. The results show that the improved algorithm proposed in this paper significantly improves the delivery rate of high-priority business. The strong QoS guarantee for high-priority business is realized.

关键词： Analytical models Protocols Spread spectrum communication Quality of service Throughput Delays Topology

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A Smart Way to Detect Islanding and Fault in Overhead Power Lines Using Magnetic Measurements

SSRN

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SSRN 2022年

作者： Ali, Malik Shah Zeb Khawaja, Arsalan Habib Afzal, Muhammad Usman, Muhammad National University of Sciences and Technology Pakistan Development and Policies Research Center Pakistan

Power system is large network consisting different components. In addition to the conventional system, when the solar system is added in Power System, the complexities increase. The system undergoes different modes of operations. To carryout efficient operation, it is necessary to operate the breaker that switches the operation of conventional system into solar system and provide continuous supply of power. The methodology is based on detection of different modes such as normal operation, fault scenario and islanding mode which will be beneficial in recognition of kind of issue through which the power system has gone. For that purpose, both Simulink tool of MATLAB and Machine learning is employed. The methodology proves to be beneficial for every situation, environment and issues for the power system. The results have been generated for normal operation, fault scenario and islanding. The accuracy of the results have been obtained by different methods of machine learning including neural network and decision tree. The system has been trained for the patterns and can accurately differentiate among three cases. The results provide efficient way of detection through a contactless method which is based on utilization of a single-phase sensor. © 2022, The Authors. All rights reserved.

关键词： Decision trees

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Optimizing Mesh Simplification: A Newton-Based Approach to Quadratic Error Metrics

Optimizing Mesh Simplification: A Newton-Based Approach to Q...

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International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI)

作者： Qingfeng Lan Fujun Yang Lei Yang School of Computer Science and Technology Southwest University of Science and Technology Mian Yang China China Aerodynamic Research and Development Center Mian Yang China

Mesh simplification is an important task in the fields of computer graphics and 3D model processing. However, the traditional quadratic error measurement method may lead to the loss of geometric features, abnormal topological changes, and even unstable results in the simplified model. To solve these problems, this paper proposes an improved quadratic error measurement method based on Newton's method. As an iterative optimization algorithm, Newton's method is known for its fast convergence speed and high accuracy and is particularly suitable for solving problems involving quadratic error metric matrices. This method also fully considers the influence of different simplified vertices on the mesh simplification results. By using the Euclidean distance metric, the simplified vertices with the smallest error from the original vertices are selected, thereby making the details of the simplified model closer to the original model. Experimental results show that the quadratic error measurement method based on Newton's method can more effectively retain the detailed features of the original model at the same simplified scale. What is even more encouraging is that this method performs well when handling model simplifications with different curvature characteristics, while the simplification results are more stable. This provides strong support for further research in the field of 3D model simplification.

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Pilot Project: Application of Multi-Component Thermal Fluid Stimulation on Shallow Heavy Oil Reservoir in Kazakhstan

Pilot Project: Application of Multi-Component Thermal Fluid ...

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2021 SPE Middle East Oil and Gas Show and Conference, MEOS 2021

作者： Yi, Leihao Hua, Xin Guan, Wenlong Xu, Shiguo Zhang, Ziyi Mei, Yizhong Guo, Erpeng Liu, Junping Zhong, Li Liu, Guohui Zheng, Xiantao Wei, Zhen China Petroleum Technology and Development Corporation CNPC China Research Institute of Petroleum Exploration and Development PetroChina Co. Ltd China CNPC Global Solutions Ltd Beijing Unobstruct Petroleum technology Service Co. China

ISBN: (纸本)9781613997727

Cyclic steam simulation (CSS) was widely used to recover heavy oil in shallow reservoirs in Kazakhstan. In the late stage of CSS in M oilfield, the performance of this CSS project was poor with high water cut and low oil steam ratio (OSR), indicating low economic benefit. The multi-component thermal fluid (MTF) stimulation trial has been conducted there since March 2018 to evaluate the feasibility of this technology. This paper introduces the field experience and the production performance of MTF stimulation. Results are from 32 cycles of MTF stimulations in 23 wells, most of which had completed their 4 cycles of CSS before. MTF technology is based on a high-pressure jet combustion mechanism, generating a mixture of nitrogen, carbon dioxide and vapor (MTF) under a sealed combustion condition. The mixture fluid provides a significant enhancement through a synergistic effect in the reservoir. The soaking and recovery process are the same as the conventional steam stimulation, meanwhile the requirements for completion and wellbore structure are the same as well. By the time of statistic, average cyclic OSR reaches 2.19 from 0.49 of last CSS cycle. Average water cut declines from 90% to 40% and daily oil production rises from 22 bbls to 33 bbls. Free water is almost invisible in the produced fluid, instead, a stable quasi-monophasic flow has been presented even at low temperatures. This effectively increases the fluidity and dilatancy of crude oil, and greatly replenishes the elastic energy of the formation. Meanwhile, with all components injected into the formation, MTF stimulation achieves significant reduction in carbon emissions. Although this is a pilot test, considerable economic benefits have been achieved with the increase of oil production efficiency. MTF stimulation brings an additional profit of USD 4.4 million for the first year under conditions of local material's cost. This successful pilot demonstrates that MTF stimulation may play an important role at la

关键词： Crude oil

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Minimal Knee Joint Space Width Detection in Digital X-Ray Images using Deep Learning

Minimal Knee Joint Space Width Detection in Digital X-Ray Im...

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Data Science, Agents & Artificial Intelligence (ICDSAAI), International Conference on

作者： A. Marimuthu A.R. Kavitha S.Sheik Abdullah Dept.of Informationtechnology Chennai Institute of Technology Chennai India Dept.of research and development Crescent Hospitals Madurai India

This analysis aimed to evaluate the performance of a deep learning-driven method to locate minimal knee joint space width area (KJSW) and see how successfully a deep learning approach can locate mKJSW area from digital x-ray images. In 1848 knee data (digital X-ray images), I used 1752 data (X-ray images) for the study. This proposed method compares the KJSW area in lateral and medial sides, and detect the mKJSW area. Faster RCNN architecture and incorporate VGG -16 with transfer learning are trained to extract the image features to locate the mKJSW area in the digital knee joint X-ray images. The proposed approach located the mKJSW region with a localization accuracy of 98.6 %, indicating the potential use of mKJSW area detection. We have presented the automated deep learning approach to locate the mKJSW area. In addition to that, our proposed deep learning approach trained on both femur and tibial bone region from knee Anterior-Posterior (AP) view digital X-ray images perform better at locating mKJSW area than the reference model. The proposed approach will be used to evaluate knee joint OA and pain assessment.

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Energy, exergy, exergoenvironmental, and exergoenviroeconomic assessment of a two stroke UAV small engine using JP5 aviation fuel and hydroxy (HHO) gas

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International Journal of Hydrogen Energy 2024年 143卷 846-861页

作者： Özer, S. Tunçer, E. Demir, U. Gülcan, H.E. Çelebi, S. Department of Mechanical Engineering Muş Alparslan University Muş Turkey Erin Engine Corporation Inc. Department of Research and Development İstanbul Turkey Department of Mechanical Engineering Faculty of Engineering and Natural Sciences İstanbul Health and Technology University İstanbul Turkey Department of Mechanical Engineering Bilecik Şeyh Edebali University Bilecik Turkey Department of Mechanical Engineering Faculty of Technology Selçuk University Konya Turkey Motor Vehicles and Transportation Technologies Dep. Arifiye Vocational School Sakarya University of Applied Science Sakarya Turkey Automotive Technologies Application and Research Center Sakarya University of Applied Sciences Sakarya Turkey

Hydroxy gas (HHO) is a gas produced by the electrolysis of water, which involves breaking down water molecules (H2O) into hydrogen (H2) and oxygen (O2) gases. When the electricity used for electrolysis comes from renewable energy sources, the resulting hydrogen can be classified as 'green hydrogen.' Therefore, by using renewable green energy sources to produce HHO gas, its application in internal combustion engines can promote clean combustion and enhance sustainability. This study explores the enhancement of performance and emission characteristics in a two-stroke Unmanned Aerial Vehicle (UAV) engine using Hydroxy gas (HHO), a green energy source produced via water electrolysis. The primary objective is to improve engine efficiency and reduce environmental impacts by employing HHO in dual-fuel mode with JP5 aviation fuel. Addressing a clear research gap in the literature, this study is the first to evaluate the energy, exergy, exergoenvironmental, and exergoeconomic aspects of a two-stroke, air-cooled UAV engine using the JP5+HHO fuel blend. Experiments were conducted at five shaft speeds (3250, 3750, 4500, 5250, 6250 rpm) and four HHO flow rates (1.0, 1.5, 2.0, 4.0 lpm). The results demonstrate that incorporating HHO gas leads to a significant improvement in engine performance, with a 10% average reduction in Brake Specific Fuel Consumption (BSFC) and a 10% increase in exergy efficiency. Additionally, the JP5+HHO 4 lpm mixture reduces exergy destruction by approximately 10% and increases heat transfer exergy by 3–10%. On the environmental front, while HHO slightly increases CO2 emissions, the exergoenvironmental impact rises by a manageable 4%. Importantly, the high HHO flow rate (4 lpm) achieves a 2% average reduction in both exergoenvironmental and exergoeconomic impacts. These findings underscore the potential of HHO as a sustainable fuel source, offering both performance gains and reduced environmental and economic costs. © 2024 Hydrogen Energy Publications LL

关键词： Unmanned aerial vehicles (UAV)

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KRLGI: Knowledge Representation Learning Based on Global Information for Reasoning

KRLGI: Knowledge Representation Learning Based on Global Inf...

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International Conference on Tools for Artificial Intelligence (ICTAI)

作者： Bo Wu Yingchi Mao Fudong Chi Yingjie Liu Silong Ding Rongzhi Qi College of Computer Science and Software Engineering Hohai University Nanjing China Technology Research and Development Center Huaneng Lancang River Hydropower Inc Kunming China

ISBN: (数字)9798331527235

ISBN: (纸本)9798331527242

Knowledge Graph Reasoning based on Representation Learning maps the entities and relations into a vector space, assessing entity-pair similarities to deduce unknown facts. However, existing methods focus solely on the local importance of entities and ignore isolated entities, leading to the issue of missing feature information. To solve this, we propose Knowledge Representation Learning based on Global Information (KRLGI). KRLGI adopts an attention-based biased random walk algorithm to obtain global information and determine the importance of global entities. The global entity importance goes through a conversion into attention weights, and these weights are integrated with the local entity importance. Subsequently, the local and global entity importance can be used together to represent entity embeddings. Globally integrated representations can reveal richer semantics and enhance reasoning capabilities. Experimental results indicate that KRLGI outperforms other baselines in reasoning accuracy on four public datasets. Notably, on the FB15k-237 dataset, KRLGI shows significant improvements over the best baseline, with increases of 6.37% in MRR, 2.5% in HITS@1, and 5.5% in HITS@10.

关键词： Representation learning Accuracy Semantics Knowledge graphs Learning (artificial intelligence) Cognition Vectors

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Bumpless Build Cube (BBCube) 3D: Heterogeneous 3D Integration Using WoW and CoW to Provide TB/s Bandwidth with Lowest Bit Access Energy

Bumpless Build Cube (BBCube) 3D: Heterogeneous 3D Integratio...

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Symposium on VLSI technology

作者： Norio Chujo Koji Sakui Shinji Sugatani Hiroyuki Ryoson Tomoji Nakamura Takayuki Ohba The WOW Alliance Tokyo Institute of Technology IIR Yokohama Japan Hitachi Ltd. Research & Development Group Yokohama Japan

We propose a technology called BBCube 3D for AI and HPC applications, which need high bandwidth and power efficiency. BBCube 3D is constructed by heterogeneous 3D integration in which xPU (CPU, GPU etc.) chiplets and DRAM wafers are stacked using a combination of bumpless Wafer-on-Wafer and Chip-on-Wafer. BBCube 3D has the potential to achieve a bandwidth 30 times higher than DDR5 and four times higher than HBM2E with an bit access energy 1/20th that of DDR5 and 1/5th that of HBM2E.

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Attack Graphs for Standalone Non-Public 5G Networks

Attack Graphs for Standalone Non-Public 5G Networks

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2022 IEEE Future Networks World Forum (FNWF)

作者： Arpit Tripathi Abhishek Thakur Bheemarjuna Reddy Tamma Indian Institute of Technology Hyderabad India Institute for Development & Research in Banking Technology Hyderabad India

Private Networks (also known as Non-Public Net-works) bring significant benefits to Industry 4.0. These networks are typically deployed on-premises of the enterprises, and their isolation from the public (consumer) networks improves the crucial aspects of security and reliability. Despite the isolation, insider attacks can be mounted on these networks. This paper analyses such attacks using attack patterns from Common Attack Pattern Enumerations and Classifications (CAPEC) database. The analysis uses attack graphs, to combine individual domains, in the context of human, device, and network vulner-abilities. The attack graphs help identify paths, the cumulative impact on the system, and possible defense techniques, including security controls to mitigate the impact. Using three sample attack graphs in the context of standalone private 5G networks, this paper analyses possible security mechanisms and captures the difference among legacy enterprise networks (including WiFi for limited mobility), public networks, and private networks.

关键词： Threat modeling 5G mobile communication Databases Fourth Industrial Revolution Security Reliability Wireless fidelity

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Numerical Simulation Study on the Effect of Horizontal Well Reservoir Stimulation for Gas Hydrate Production

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Acta Geologica Sinica(English Edition) 2022年第2期96卷 701-712页

作者： LI Xiaoyang TIAN Yingying ZHANG Xin SONG Gang ZHAO Ming LIANG Jinqiang HUANG Wei MENG Fanle Institute of Exploration Techniques China Geological SurveyLangfangHebei 065000China Directional Drilling Technology Innovation Center China Geological SurveyLangfangHebei 065000China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 511466China Research Institute of Petroleum Exploration and Development Beijing 100083China

A new gas hydrate reservoir stimulation method of in-situ fracturing with transient heating is proposed, in line with analysis of the technological bottlenecks faced by marine gas hydrate production. This method injects the developed chemical reagents into a hydrate reservoir through hydraulic fracturing, releasing heat during the chemical reaction to increase the hydrate decomposition rate. The chemical reaction product furthermore has a honeycomb structure to support fractures and increase reservoir permeability. Based on the geological model of natural gas hydrate in the South China Sea, three development methods are simulated to evaluate hydrate production capacity, consisting of horizontal well, fractured horizontal well and in-situ fracturing with transient heating well. Compared with the horizontal well, the simulation results show that the cumulative gas production of the fractured horizontal well in one year is 7 times that of the horizontal well, while the cumulative gas production of in-situ fracturing with transient heating well is 12 times that of the horizontal well, which significantly improves daily efficiency and cumulative gas production. In addition, the variation patterns of hydrate saturation and temperature-pressure fields with production time for the three exploitation plans are presented, it being found that three sensitive parameters of fracture conductivity, fracture half-length and fracture number are positively correlated with hydrate production enhancement. Through the simulations, basic data and theoretical support for the optimization of gas hydrate reservoir stimulation scheme has been provided.

关键词： natural gas hydrate horizontal well reservoir stimulation transient heating seepage channel hydraulic fracturing production enhancement technology

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