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Positioning of Hydrogen Energy and Development of Hydrogen Pipeline Transportation Technology in the Context of Carbon Neutrality
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作者 Wang Zhi 《China Oil & Gas》 CAS 2023年第5期42-48,共7页
The correct understanding of the role of hydrogen energy in the carbon neutrality strategy,and the scientific development of the technical layout of hydrogen energy industry chain are key factors in determining whethe... The correct understanding of the role of hydrogen energy in the carbon neutrality strategy,and the scientific development of the technical layout of hydrogen energy industry chain are key factors in determining whether the hydrogen energy industry and enterprises can achieve healthy sustainable development by following the national trend.This paper discusses the role of hydrogen energy in the implementation of the carbon neutrality strategy,and analyzes the necessity of hydrogen pipeline transportation,and the main technical challenges brought about by the physical and chemical differences between hydrogen and natural gas.We also introduce the technical breakthroughs and main achievements against the construction of the“West-East Hydrogen Transport”pipeline project to provide guidance and reference for the hydrogen energy industry and the construction of hydrogen transportation pipelines.In order to better promote the steady and healthy development of the domestic hydrogen pipeline transportation industry,we offer some proposals for the spatial layout integration and optimization of carbon,nitrogen,hydrogen,and oxygen elements and the research and application of large-scale hydrogen storage technology based on the work practices. 展开更多
关键词 BREAKTHROUGH HYDROGEN pipeline
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A Study on Integrated Construction of Luzhou Comprehensive Transportation Hub
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作者 Peng Xu 《Journal of Civil Engineering and Architecture》 2024年第1期6-11,共6页
The target of integrated construction of comprehensive transportation hub is to integrate the traffic resources,achieve butt joint of pan-regional transportation mode,and finally realize the"seamless connection&q... The target of integrated construction of comprehensive transportation hub is to integrate the traffic resources,achieve butt joint of pan-regional transportation mode,and finally realize the"seamless connection"of the goods and"zero transfer"of the passenger traffic.Relying on the particularity of the geographical location and the convenience of the Yangtze River channel,Luzhou puts forth effort to build a comprehensive transport hub in Southern Sichuan and has made great efforts in traffic infrastructure construction.However,there are still some problems.Combining practice of Luzhou,using the advanced experience of foreign and domestic cities for reference,the paper pointed out that for the sake of constructing a comprehensive transportation hub,we need to build the traffic integration on the basis of the efficiency.Besides,the paper proposed the strategies for construction. 展开更多
关键词 comprehensive transportation hub INTEGRATION construction strategies
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Optimizing a Transportation System Using Metaheuristics Approaches (EGD/GA/ACO): A Forest Vehicle Routing Case Study
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作者 Hossein Havaeji Thien-My Dao Tony Wong 《World Journal of Engineering and Technology》 2024年第1期141-157,共17页
The large-scale optimization problem requires some optimization techniques, and the Metaheuristics approach is highly useful for solving difficult optimization problems in practice. The purpose of the research is to o... The large-scale optimization problem requires some optimization techniques, and the Metaheuristics approach is highly useful for solving difficult optimization problems in practice. The purpose of the research is to optimize the transportation system with the help of this approach. We selected forest vehicle routing data as the case study to minimize the total cost and the distance of the forest transportation system. Matlab software helps us find the best solution for this case by applying three algorithms of Metaheuristics: Genetic Algorithm (GA), Ant Colony Optimization (ACO), and Extended Great Deluge (EGD). The results show that GA, compared to ACO and EGD, provides the best solution for the cost and the length of our case study. EGD is the second preferred approach, and ACO offers the last solution. 展开更多
关键词 Metaheuristics Algorithms transportation costs Optimization Approach cost Minimisation
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Study on characteristics of pipeline transportation and sulfur fixing of cleaned coal logs 被引量:1
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作者 林愉 林群 +1 位作者 唐军 刘同成 《Journal of Coal Science & Engineering(China)》 2006年第1期91-95,共5页
As special cylindrical briquettes of coal for long distance pipeline transportation and directly cleaned combustion the cleaned coal logs should possess two characteristics of transportation in pipeline and cleaned co... As special cylindrical briquettes of coal for long distance pipeline transportation and directly cleaned combustion the cleaned coal logs should possess two characteristics of transportation in pipeline and cleaned combustion. In order to make cleaned coal logs a rational technology for manufacturing, cleaned coal logs was designed and compound sulfur fixing binders with high effects of binding and sulfur-fixing was selected and combined. In addition, by means of characteristic experiments of strength, wear, waterproof and sulfur-fixing five different cleaned coal logs made with different compound sulfur fixing binders in different compaction conditions was tested and measured. Experimental results indicated that the manufacturing technology of cleaned coal logs was reasonable and the combination of compound sulfur fixing binders was scientific. Cleaned coal logs made up with the fourth group of coal mixture had high strength, good waterproof property, efficient sulfur-fixing, good characteristic of transportion, and achieved the performance requirement for pipeline transportation and sulfur fixing. 展开更多
关键词 精煤 管道输运 选煤 硫磺固定
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Sacrificial piles as a countermeasure against local scour around underwater pipelines
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作者 Forough Raeisi Seyed Mohammad Ali Zomorodiann +1 位作者 Masih Zolghadr Hazi Mohammad Azamathulla 《Water Science and Engineering》 EI CAS CSCD 2024年第2期187-196,共10页
Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed ... Local scour around pipelines crossing rivers or in marine environments is a significant concern.It can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.Maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles. 展开更多
关键词 Clear water River crossing pipeline Local scour Self-burial process Sediment transport
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Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite
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作者 Seyed Mohammad Reza Abtahi Saeid Ansari Sadrabadi +4 位作者 Gholam Hosein Rahimi Gaurav Singh Hamid Abyar Daniele Amato Luigi Federico 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1783-1806,共24页
Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necess... Repairs of corroded high-pressure pipelines are essential for fluids transportation under high pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necessary strength.Therefore,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME B31.G.In addition,the experimental tests are replicated numerically using the finite element method.Setting the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high pressure.The direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the defect.Composite reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed. 展开更多
关键词 High-pressure pipeline composite repair ASME PCC-2 ISO 24817
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Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria
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作者 Jian-Yu He Fei Xie +3 位作者 Dan Wang Guang-Xin Liu Ming Wu Yue Qin 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1320-1332,共13页
Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil env... Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence. 展开更多
关键词 Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines
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SDH-FCOS:An Efficient Neural Network for Defect Detection in Urban Underground Pipelines
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作者 Bin Zhou Bo Li +2 位作者 Wenfei Lan Congwen Tian Wei Yao 《Computers, Materials & Continua》 SCIE EI 2024年第1期633-652,共20页
Urban underground pipelines are an important infrastructure in cities,and timely investigation of problems in underground pipelines can help ensure the normal operation of cities.Owing to the growing demand for defect... Urban underground pipelines are an important infrastructure in cities,and timely investigation of problems in underground pipelines can help ensure the normal operation of cities.Owing to the growing demand for defect detection in urban underground pipelines,this study developed an improved defect detection method for urban underground pipelines based on fully convolutional one-stage object detector(FCOS),called spatial pyramid pooling-fast(SPPF)feature fusion and dual detection heads based on FCOS(SDH-FCOS)model.This study improved the feature fusion component of the model network based on FCOS,introduced an SPPF network structure behind the last output feature layer of the backbone network,fused the local and global features,added a top-down path to accelerate the circulation of shallowinformation,and enriched the semantic information acquired by shallow features.The ability of the model to detect objects with multiple morphologies was strengthened by introducing dual detection heads.The experimental results using an open dataset of underground pipes show that the proposed SDH-FCOS model can recognize underground pipe defects more accurately;the average accuracy was improved by 2.7% compared with the original FCOS model,reducing the leakage rate to a large extent and achieving real-time detection.Also,our model achieved a good trade-off between accuracy and speed compared with other mainstream methods.This proved the effectiveness of the proposed model. 展开更多
关键词 Urban underground pipelines defect detection SDH-FcoS feature fusion SPPF dual detection heads
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Numerical study on local scour characteristics around submarine pipelines in the Yellow River Delta silty sandy soil under waves and currents
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作者 Peng Yu Ruigeng Hu +4 位作者 Jike Zhang Qi Yang Jieru Zhao Lei Cao Chenghao Zhu 《Deep Underground Science and Engineering》 2024年第2期182-196,共15页
Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource engineering.Due to the interaction of waves,currents,seabed,and pipeline structures,the soil aroun... Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource engineering.Due to the interaction of waves,currents,seabed,and pipeline structures,the soil around submarine pipelines is prone to local scour,severely affecting their operational safety.With the Yellow River Delta as the research area and based on the renormalized group(RNG)k-εturbulence model and Stokes fifth-order wave theory,this study solves the Navier-Stokes(N-S)equation using the finite difference method.The volume of fluid(VOF)method is used to describe the fluid-free surface,and a threedimensional numerical model of currents and waves-submarine pipeline-silty sandy seabed is established.The rationality of the numerical model is verified using a self-built waveflow flume.On this basis,in this study,the local scour development and characteristics of submarine pipelines in the Yellow River Delta silty sandy seabed in the prototype environment are explored and the influence of the presence of pipelines on hydrodynamic features such as surrounding flow field,shear stress,and turbulence intensity is analyzed.The results indicate that(1)local scour around submarine pipelines can be divided into three stages:rapid scour,slow scour,and stable scour.The maximum scour depth occurs directly below the pipeline,and the shape of the scour pits is asymmetric.(2)As the water depth decreases and the pipeline suspension height increases,the scour becomes more intense.(3)When currents go through a pipeline,a clear stagnation point is formed in front of the pipeline,and the flow velocity is positively correlated with the depth of scour.This study can provide a valuable reference for the protection of submarine pipelines in this area. 展开更多
关键词 local scour numerical simulation submarine pipelines Yellow River Delta
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Dynamic response of mountain tunnel,bridge,and embankment along the Sichuan-Tibet transportation corridor to active fault based on model tests
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作者 HUANG Beixiu QIAO Sijia +2 位作者 CHEN Xulei LI Lihui QI Shengwen 《Journal of Mountain Science》 SCIE CSCD 2024年第1期182-199,共18页
The Sichuan-Tibet transportation corridor is prone to numerous active faults and frequent strong earthquakes.While extensive studies have individually explored the effect of active faults and strong earthquakes on dif... The Sichuan-Tibet transportation corridor is prone to numerous active faults and frequent strong earthquakes.While extensive studies have individually explored the effect of active faults and strong earthquakes on different engineering structures,their combined effect remains unclear.This research employed multiple physical model tests to investigate the dynamic response of various engineering structures,including tunnels,bridges,and embankments,under the simultaneous influence of cumulative earthquakes and stick-slip misalignment of an active fault.The prototype selected for this study was the Kanding No.2 tunnel,which crosses the Yunongxi fault zone within the Sichuan-Tibet transportation corridor.The results demonstrated that the tunnel,bridge,and embankment exhibited amplification in response to the input seismic wave,with the amplification effect gradually decreasing as the input peak ground acceleration(PGA)increased.The PGAs of different engineering structures were weakened by the fault rupture zone.Nevertheless,the misalignment of the active fault may decrease the overall stiffness of the engineering structure,leading to more severe damage,with a small contribution from seismic vibration.Additionally,the seismic vibration effect might be enlarged with the height of the engineering structure,and the tunnel is supposed to have a smaller PGA and lower dynamic earth pressure compared to bridges and embankments in strong earthquake zones crossing active faults.The findings contribute valuable insights for evaluating the dynamic response of various engineering structures crossing an active fault and provide an experimental reference for secure engineering design in the challenging conditions of the Sichuan-Tibet transportation corridor. 展开更多
关键词 Dynamic response Engineering structure Sichuan-Tibet transportation corridor Active fault EARTHQUAKE Model test
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Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity
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作者 HUANG Xiaoyan KANG Chenchen +1 位作者 YIN Chun TANG Junqing 《Chinese Geographical Science》 SCIE CSCD 2024年第3期453-467,共15页
Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility ... Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system. 展开更多
关键词 transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China
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Prediction on Failure Pressure of Pipeline Containing Corrosion Defects Based on ISSA-BPNNModel
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作者 Qi Zhuang Dong Liu Zhuo Chen 《Energy Engineering》 EI 2024年第3期821-834,共14页
Oil and gas pipelines are affected by many factors,such as pipe wall thinning and pipeline rupture.Accurate prediction of failure pressure of oil and gas pipelines can provide technical support for pipeline safety man... Oil and gas pipelines are affected by many factors,such as pipe wall thinning and pipeline rupture.Accurate prediction of failure pressure of oil and gas pipelines can provide technical support for pipeline safety management.Aiming at the shortcomings of the BP Neural Network(BPNN)model,such as low learning efficiency,sensitivity to initial weights,and easy falling into a local optimal state,an Improved Sparrow Search Algorithm(ISSA)is adopted to optimize the initial weights and thresholds of BPNN,and an ISSA-BPNN failure pressure prediction model for corroded pipelines is established.Taking 61 sets of pipelines blasting test data as an example,the prediction model was built and predicted by MATLAB software,and compared with the BPNN model,GA-BPNN model,and SSA-BPNN model.The results show that the MAPE of the ISSA-BPNN model is 3.4177%,and the R2 is 0.9880,both of which are superior to its comparison model.Using the ISSA-BPNN model has high prediction accuracy and stability,and can provide support for pipeline inspection and maintenance. 展开更多
关键词 Oil and gas pipeline corrosion defect failure pressure prediction sparrow search algorithm BP neural network logistic chaotic map
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Design and Application of Intelligent Control System for Molten Iron Transportation Based on 5G Technology
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作者 Borui Wang 《Frontiers of Metallurgical Industry》 2024年第2期21-24,共4页
Molten transport is an important link in the iron and steel enterprise production,involves many complex factors,artificial management is difficult.Therefore,puts forward a kind of molten iron transport wisdom control ... Molten transport is an important link in the iron and steel enterprise production,involves many complex factors,artificial management is difficult.Therefore,puts forward a kind of molten iron transport wisdom control system based on 5G technology,which mainly contains the intelligent identification tracking system,equipment status collection information acquisition system,locomotive vehicle terminal system,etc.Combined with the analysis of the actual application situation,the system could integrate all the processes and elements of molten iron produc-tion and transportation,realize the integration of operation and management,and also promote the improvement of the turnover efficiency of molten iron tank,reduce the demand for personnel,and reduce the labor cost. 展开更多
关键词 5G technology molten iron transportation intelligent control system
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Development of a Low-Cost Prototype System for Pipeline Operational and Vandalism Spillage Detection and Validation Framework
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作者 Buloere Florence Ekeu-Wei Iguniwari Thomas Ekeu-Wei 《Advances in Internet of Things》 2024年第2期21-35,共15页
Crude oil spillage is a major challenge in Nigeria. It affects the environment, health, life, and livelihood of residents of the Niger Delta region, where oil is explored, processed, and transported via a network of p... Crude oil spillage is a major challenge in Nigeria. It affects the environment, health, life, and livelihood of residents of the Niger Delta region, where oil is explored, processed, and transported via a network of pipelines. Oil spillage is primarily caused by vandalization/sabotage and operational issues such as corrosion, equipment failure, operation, and maintenance errors. Thus, prompt response is required to mitigate the impact of oil spills. In this study, we deployed low-cost Arduino systems, including sensors (vibration and flow), modules (GPS and Wifi) and an IoT platform (ThingSpeak) to detect spillage caused by vandalism and operational inefficiencies proactively. The results demonstrate that low-cost sensors can detect changes in the flow volume between the inflow and outflow attributable to spillage, and vibration shocks caused by vandalism can be detected and linked to the cause of the spillage and communicated in real time to inform response action. Moreover, we proposed a framework for field validation utilizing KoboToolBox (a crowdsourcing/citizen science platform). The prototype system designed and programmed showed promising results, as it could detect spillage for vandalism and operational scenarios in real-time, quantify the volume of spillage, and identify the location and time of spillage occurrence;indicators relevant for response planning to minimize the impact of oil spillage. A video demonstration of the prototype system developed is accessible via: https://youtu.be/wKa9MZvYf1w. . 展开更多
关键词 Crude Oil LEAKAGE pipeline VANDALISM ARDUINO Crowdsourcing Niger Delta
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Improving Supply Chain Strategies towards Mitigating the Effect of Crude Oil Theft and Pipeline Vandalism in the Nigerian Oil and Gas Industry: A Case Study of the Nigerian National Petroleum Corporation (NNPC)
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作者 Ruth Agwom Panle 《Open Journal of Yangtze Oil and Gas》 2024年第3期75-93,共19页
Generically, SCM may be said to include all activities carried out to ensure proper functioning of the supply chain. The activities included in proper management of a supply chain broadly include logistics activities,... Generically, SCM may be said to include all activities carried out to ensure proper functioning of the supply chain. The activities included in proper management of a supply chain broadly include logistics activities, planning and control of the flow of information and materials in a firm, management of relationships with other organizations and government intervention, However, crude oil theft and pipeline vandalism are established products supply chain disruptors in Nigeria which are rendering the task of running an efficient petroleum supply chain onerous. This paper aims to establish the importance of effective supply chain strategies for companies in the oil and gas industry with special focus on the Nigerian oil and gas sector and the strategies by which the state oil and gas corporation in this sector may mitigate disruptions to its supply chain. This study investigates the enhancement of supply chain strategies towards meeting the challenge of crude oil theft and pipeline vandalism, using the Nigerian National Corporation (NNPC) as a case study. Based on this study, data were collected from two sources: A summary of incident reports obtained from NNPC and an interview with personnel in the PPMC Department. Incident report refers to a report produced when accidents such as equipment failure, injury, loss of life, or fire occur at the work site. Content analysis is utilized to evaluate data obtained from interview responses, CBN financial stability reports, NDIC annual reports, circulars, banking supervision reports and implementation guidelines. The study found out that NNPC should endeavor to sustain its value chain and ward of pipeline vandals and crude oil thieves by engaging in community partnership, detailing security outfits to ensure its pipelines’ right of way and bridging. Concluded that the oil supply chain of the Nigerian National Petroleum Corporation has been plagued by disruptions in the form of crude oil theft and pipeline vandalism which has had debilitating effects on its value. 展开更多
关键词 Supply Chain Strategies Management Production Crude Oil THEFT pipeline Vandalism Information Technology Operations
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Analysis of Historic Pavement and Bridge Conditions and Alternative Funding Levels for the Michigan Department of Transportation
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作者 William Robert 《Journal of Traffic and Transportation Engineering》 2024年第3期107-118,共12页
In 1997 the Michigan Department of Transportation (MDOT) established an ambitious set of condition targets for its pavements and bridges, and the Department received increased revenue from a 4-cent-per-gallon increase... In 1997 the Michigan Department of Transportation (MDOT) established an ambitious set of condition targets for its pavements and bridges, and the Department received increased revenue from a 4-cent-per-gallon increase in the state motor fuels tax to help meet its targets. However, over time, actual revenue was less than both what was initially estimated as needed to meet the targets and what was projected from the tax increase. Consequently, actual conditions were projected to fall short of the target levels, so the department issued bonds to address the shortfall through 2012. To support deliberations on future funding, in 2013 MDOT performed an analysis of historic conditions to determine what additional fuel tax revenues would have been required beginning in 1997 to: replace bond revenues used to fund pavement and bridge projects from 1997 to 2012;and enable MDOT to meet its condition targets. The analysis was performed using data on actual pavement and bridge funding and conditions;as well as predicted funding and conditions for different hypothetical increases in fuel taxes. The analysis concluded that, in addition to the actual increase of 4 cents per gallon, a fuel tax increase of another 10 cents per gallon would have been required in 1997 to replace bond revenue used for pavement and bridges and allow MDOT to meet its condition targets. The analysis results were used to help inform the discussion of Michigan’s target asset conditions and funding, and demonstrate application of MDOT’s pavement and bridge management systems for performing historic analyses. 展开更多
关键词 transportation asset management transportation finance performance measures pavement management bridge management
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Wall slip behavior of cemented paste backfill slurry during pipeline based on noncontact experimental detection 被引量:2
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作者 Zhenlin Xue Haikuan Sun +2 位作者 Deqing Gan Zepeng Yan Zhiyi Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第8期1515-1523,共9页
Wall slip is a microscopic phenomenon of cemented paste backfill(CPB)slurry near the pipe wall,which has an important influence on the form of slurry pipe transport flow and velocity distribution.Directly probing the ... Wall slip is a microscopic phenomenon of cemented paste backfill(CPB)slurry near the pipe wall,which has an important influence on the form of slurry pipe transport flow and velocity distribution.Directly probing the wall slip characteristics using conventional experimental methods is difficult.Therefore,this paper established a noncontact experimental platform for monitoring the microscopic slip layer of CPB pipeline transport independently based on particle image velocimetry(PIV)and analyzed the effects of slurry temperature,pipe diameter,solid concentration,and slurry flow on the wall slip velocity of the CPB slurry,which refined the theory of the effect of wall slip characteristics on pipeline transport.The results showed that the CPB slurry had an extensive slip layer at the pipe wall with significant wall slip.High slurry temperature improved the degree of particle Brownian motion within the slurry and enhanced the wall slip effect.Increasing the pipe diameter was not conducive to the formation of the slurry slip layer and led to a transition in the CPB slurry flow pattern.The increase in the solid concentration raised the interlayer shear effect of CPB slurry flow and the slip velocity.The slip velocity value increased from 0.025 to 0.056 m·s^(-1)when the solid content improved from 55wt%to 65wt%.When slurry flow increased,the CPB slurry flocculation structure changed,which affected the slip velocity,and the best effect of slip layer resistance reduction was achieved when the transported flow rate was 1.01 m^(3)·h^(-1).The results had important theoretical significance for improving the stability and economy of the CPB slurry in the pipeline. 展开更多
关键词 particle image velocimetry cemented paste backfill noncontact experimental platform wall slip behavior pipeline transportation
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Combinations of Transportation Policies to Promote BRT Usage Using Artificial Society Model
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作者 Hiroaki Inokuchi 《Journal of Traffic and Transportation Engineering》 2024年第1期1-10,共10页
Various transportation systems have been developed in recent years.In this study,an artificial society model is developed to examine the combination of transportation policies in urban areas.In this model,each trip ma... Various transportation systems have been developed in recent years.In this study,an artificial society model is developed to examine the combination of transportation policies in urban areas.In this model,each trip maker selects the primary and terminal transportation modes.An artificial society model is applied to the southeastern region of Osaka City,Japan.The effects of introducing BRT(bus rapid transit,primary transportation)and on-demand buses(terminal transportation)are investigated.The results confirm that BRT is used by a certain number of users.An increase in the use of BRT will increase the amount of walking,thus resulting in a healthy city.However,on-demand buses are rarely used as terminal transportation.Additionally,the development of bicycle parking stations near BRT stops is shown to be effective in the northern section of the BRT route. 展开更多
关键词 Artificial society model bus rapid transit on-demand bus transportation policy.
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Corrosion-Based Integrity Analysis of Offshore Pipeline for Hydrocarbon Transportation
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作者 David Emmanuel Udonsek Daniel Tamonodukobipi Victor Effiong Odokwo 《Journal of Power and Energy Engineering》 2023年第5期24-41,共18页
Conventional pipeline corrosion assessment methods result in failure pressure predictions that are conservative, especially for pipelines that are subjected to internal pressure and axial compressive stress. Alternati... Conventional pipeline corrosion assessment methods result in failure pressure predictions that are conservative, especially for pipelines that are subjected to internal pressure and axial compressive stress. Alternatively, numerical methods may be used. However, they are computationally expensive. This paper proposes an analytical equation based on finite element analysis (FEA) for failure pressure prediction of a high toughness corroded pipeline with a single corrosion defect subjected to internal pressure and axial compressive stress. The equations were developed based on the weights and biases of an Artificial Neural Network (ANN) model trained with failure pressure from finite element analysis (FEA) of a high toughness pipeline for various defect depths, defect lengths, and axial compressive stresses. The proposed model was validated against actual burst test results for high toughness materials and was found to be capable of making accurate predictions with a coefficient of determination (R<sup>2</sup>) of 0.99. An extensive parametric study using the proposed model was subsequently conducted to determine the effects of defect length, defect depth, and axial compressive stress on the failure pressure of a corroded pipe with a single defect. The application of ANN together with FEA has shown promising results in the development of an empirical solution for the failure pressure prediction of pipes with a single corrosion defect subjected to internal pressure and axial compressive stress. 展开更多
关键词 FAILURE Prediction Marine pipelines Crude Oil Subsea
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Experimental research on the contact force of the bi-directional pig in oil and gas pipeline
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作者 Xiao-Xiao Zhu Chun-Ming Fu +1 位作者 Yu-Tao Wang Shi-Ming Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期474-481,共8页
The migration process of the pig in oil and gas pipeline is a complex dynamic problem.During the pigging operation,the variation of friction force caused by the nonlinear contact between the sealing disc and the pipe ... The migration process of the pig in oil and gas pipeline is a complex dynamic problem.During the pigging operation,the variation of friction force caused by the nonlinear contact between the sealing disc and the pipe wall is the key factor affecting the dynamic characteristics of the pig motion.At present,the existed pigging models for predicting pigging behavior regard friction as an invariant constant.Experimental research indicates that the friction force of the pig varies with the contact force and the lubrication conditions.Therefore,the assumption that the friction force is constant cannot reflect the friction dynamic characteristics of the pig during pigging,and will also affect the accuracy of the pigging model.Exploring the variation of friction force of pig under different conditions is the basis of establishing the transient dynamic model of a pig.As a result,in this paper,a method of direct measurement of contact force between the pig and the pipeline is presented,the contact force,the friction force,as well as the friction coefficient of the pig are obtained from the experiment.Research results in this paper can help to establish a more accurate dynamic model of pig. 展开更多
关键词 pipeline pig Sealing disc contact force Friction coefficient Experimental rig
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