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Petroleum Exploration and Development 2019年第3期46卷 565-575页

作者： SALIMIDELSHAD Yaser MORADZADEH Ali KAZEMZADEH Ezatallah POURAFSHARY Peyman majdi abbas School of Mining Engineering College of Engineering University of Tehran Tehran *** Iran Faculty of Research and Development in Upstream Petroleum Industry Research Institute of Petroleum Industry Tehran *** Iran Department of Petroleum Engineering School of Mining and Geosciences Nazarbayev University Astana 010000 Kazakhstan

To examine the effect of pressure on pore structure and petrophysical properties of carbonate rock, the porosity, permeability, CT scanning, SEM and elastic wave velocity of two carbonate core plug samples from an oilfield in Southwest Iran were analyzed under cyclic pressure. One of the plugs was calcite and the other was dolomite with anhydrite nodules. The cyclic pressure exerted on the samples increased from 13.79 MPa to 27.58 MPa in six steps, and the variations in petrophysical properties of the two samples at different pressure loading and unloading steps were counted and analyzed. The results show that the calcite sample decreases in porosity and permeability with the increase of pressure, which is consistent with the results from compression and shear wave velocity tests. In the dolomite sample, the decreasing trend was not observed;fluctuations of compressive and shear velocities were observed during the loading stage, which may be due to different geometries of the pores and the porosity variation in the sample. Understanding the variation of carbonate petrophysical properties with pressure is helpful for optimizing reservoir development scheme.

关键词： cyclic pressure loading petrophysical property carbonate reservoir, CT scan rock physical property structure deformation

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碳酸盐岩储集层岩石物性变化与结构变形实验

石油勘探与开发 2019年第3期46卷 542-551页

作者： SALIMIDELSHAD Yaser MORADZADEH Ali KAZEMZADEH Ezatallah POURAFSHARY Peyman majdi abbas School of Mining Engineering College of Engineering University of Tehran Faculty of Research and Development in Upstream Petroleum Industry Research Institute of Petroleum IndustryTehran Department of Petroleum Engineering School of Mining and Geosciences Nazarbayev University

为研究压力对碳酸盐岩孔隙结构、岩石物理性质等方面的影响,在压力循环加载条件下对伊朗西南部South-Pars气田下三叠统Kangan组2个碳酸盐岩柱状岩心样品进行孔隙度、渗透率、CT扫描、扫描电子显微镜(SEM)、弹性波速度等分析。在2个岩心... 详细信息

为研究压力对碳酸盐岩孔隙结构、岩石物理性质等方面的影响,在压力循环加载条件下对伊朗西南部South-Pars气田下三叠统Kangan组2个碳酸盐岩柱状岩心样品进行孔隙度、渗透率、CT扫描、扫描电子显微镜(SEM)、弹性波速度等分析。在2个岩心样品中,一个样品为方解石,另一个为含硬石膏结核的白云石,分别以6个阶段循环施加13.79 MPa和27.58 MPa的负载压力,统计分析2个样品在不同压力加载/卸载阶段下的物性变化特点。结果表明,方解石样品的孔隙度和渗透率随压力载荷的增加而减小,这与纵波和横波速度测试的结果一致。在白云石样品中则没有观察到这种趋势。在纵波和横波速度分析中可观察到压力加载阶段速度发生起伏,这可能是由于孔隙具有不同几何形状和样品中的孔隙发生变化所致。研究碳酸盐岩物性随压力的变化有助于优化调整油气藏开发方案。

关键词：压力循环加载岩石物性碳酸盐岩储集层 CT扫描 South-Pars气田下三叠统Kangan组结构变形

Prediction of representative deformation modulus of longwall panel roof rock strata using Mamdani fuzzy system

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International Journal of Mining Science and Technology 2015年第1期25卷 23-30页

作者： Mohammad Rezaei Mostafa Asadizadeh abbas majdi Mohammad Farouq Hossaini School of Mining Engineering College of Engineering University of Tehran

Deformation modulus is the important parameter in stability analysis of tunnels, dams and mining structures. In this paper, two predictive models including Mamdani fuzzy system(MFS) and multivariable regression analysis(MVRA) were developed to predict deformation modulus based on data obtained from dilatometer tests carried out in Bakhtiary dam site and additional data collected from longwall coal mines. Models inputs were considered to be rock quality designation, overburden height, weathering,unconfined compressive strength, bedding inclination to core axis, joint roughness coefficient and fill thickness. To control the models performance, calculating indices such as root mean square error(RMSE),variance account for(VAF) and determination coefficient(R2) were used. The MFS results show the significant prediction accuracy along with high performance compared to MVRA results. Finally, the sensitivity analysis of MFS results shows that the most and the least effective parameters on deformation modulus are weathering and overburden height, respectively.

关键词： Mamdani模糊系统预测模型变形模量顶板岩层无侧限抗压强度面板稳定性分析均方根误差

Development of a time-dependent energy model to calculate the mining-induced stress over gates and pillars

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 306-317页

作者： Mohammad Rezaei Mohammad Farouq Hossaini abbas majdi School of Mining Engineering College of Engineering University of Tehran

Generally, longwall mining-induced stress results from the stress relaxation due to destressed zone that occurs above the mined panel. Knowledge of induced stress is very important for accurate design of adjacent gateroads and intervening pillars which helps to raise the safety and productivity of longwall mining operations. This study presents a novel time-dependent analytical model for determination of the longwall mining-induced stress and investigates the coefficient of stress concentration over adjacent gates and pillars. The model is developed based on the strain energy balance in longwall mining incorporated to a rheological constitutive model of caved materials with time-varying parameters. The study site is the Tabas coal mine of Iran. In the proposed model, height of destressed zone above the mined panel, total longwall mining-induced stress, abutment angle, induced vertical stress, and coefficient of stress concentration over neighboring gates and intervening pillars are calculated. To evaluate the effect of proposed model parameters on the coefficient of stress concentration due to longwall mining, sensitivity analysis is performed based on the field data and experimental constants. Also, the results of the proposed model are compared with those of existing models. The comparative results confirm a good agreement between the proposed model and the in situ measurements. According to the obtained results, it is concluded that the proposed model can be successfully used to calculate the longwall mining-induced stress. Therefore, the optimum design of gate supports and pillar dimensions would be attainable which helps to increase the mining efficiency.

关键词： Longwall mining Strain energy Time-dependent model Destressed zone Mining-induced stress

Flow Regimes in Bubble Columns with and without Internals: A Review

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Fluid Dynamics & Materials Processing 2024年第2期20卷 239-256页

作者： Ayat N.Mahmood Amer A.Abdulrahman Laith S.Sabri abbas J.Sultan Hasan Shakir majdi Muthanna H.Al-Dahhan Department of Chemical Engineering University of Technology-IraqBaghdadIraq Chemical and Petroleum Industries Engineering Department Al-Mustaqbal University CollegeBabylonIraq Department of Chemical and Biochemical Engineering Missouri University of Science and TechnologyRollaUSA

Hydrodynamics characterization in terms ofﬂow regime behavior is a crucial task to enhance the design of bubble column reactors and scaling up related methodologies.This review presents recent studies on the typicalﬂow regimes established in bubble columns.Some effort is also provided to introduce relevant deﬁnitions pertaining to thisﬁeld,namely,that of“void fraction”and related(local,chordal,cross-sectional and volumetric)variants.Experimental studies involving different parameters that affect design and operating conditions are also discussed in detail.In the second part of the review,the attention is shifted to cases with internals of various types(perfo-rated plates,bafﬂes,vibrating helical springs,mixers,and heat exchanger tubes)immersed in the bubble columns.It is shown that the presence of these elements has a limited inﬂuence on the global column hydrodynamics.However,they can make the homogeneousﬂow regime more stable in terms of transition gas velocity and transi-tion holdup value.The last section is used to highlight gaps which have not beenﬁlled yet and future directions of investigation.

关键词： Hydrodynamics ﬂow regime bubble column heat-exchanging internals

Spontaneous Paravesical and Broad Ligament Hematoma after Vaginal Delivery Had Uterine Artery Embolization after Evacuating the Hematoma

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Open Journal of Obstetrics and Gynecology 2024年第3期14卷 480-486页

作者： Aayat Jaaffar Naseeb Abrar majdi Al Nasheet Salmaniya Medical Complex Manama Bahrain

Broad ligament hematoma is typically seen during cesarean section due to rupture of branches of uterine and vaginal vessels and it’s rare to be seen post-normal vaginal delivery. Addressing puerperal hematomas postpartum presents considerable challenges for obstetric care providers. While hematomas such as those affecting the vulva, vulvovaginal region, or paravaginal area are frequently encountered, retroperitoneal hematomas are rare and notably pose a greater risk to the life of the patient. The medical literature contains scant case reports on retroperitoneal hematomas, with no consensus on a definitive treatment approach. Pelvic arterial embolization has emerged as both a sensible and increasingly preferred method for treating these hematomas recently, but its application is contingent upon the patient maintaining hemodynamic stability and the availability of a specialized interventional embolization unit. In our case, we are presenting a very rare case of a 31-year-old primigravida female with a history of in vitro fertilization pregnancy. She delivered a normal vaginal delivery at 31 weeks gestation. Unfortunately, she experienced multiple complications intrapartum, including preeclampsia and placental abruption. These complications increased her risk of developing a broad ligament hematoma.

关键词： Broad Ligament Paravesical Hematoma Spontaneous Hematoma Uterine Artery Embolization Retroperitoneal Hematoma Vaginal Delivery

A Boosted Tree-Based Predictive Model for Business Analytics

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Intelligent Automation & Soft Computing 2023年第4期36卷 515-527页

作者： Mohammad Al-Omari Fadi Qutaishat majdi Rawashdeh Samah H.Alajmani Mehedi Masud Department of Business Information Technology Princess Sumaya University for TechnologyAmmanJordan Department of Information Technology College of Computer and Information TechnologyTaif UniversityP.O.Box.11099Taif21994Saudi Arabia Department of Computer Science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

Business Analytics is one of the vital processes that must be incorpo-rated into any business.It supports decision-makers in analyzing and predicting future trends based on facts(Data-driven decisions),especially when dealing with a massive amount of business data.Decision Trees are essential for business ana-lytics to predict business opportunities and future trends that can retain corpora-tions’competitive advantage and survival and improve their business value.This research proposes a tree-based predictive model for business analytics.The model is developed based on ranking business features and gradient-boosted trees.For validation purposes,the model is tested on a real-world dataset of Universal Bank to predict personal loan acceptance.It is validated based on Accuracy,Precision,Recall,and F-score.The experimentﬁndings show that the proposed model can predict personal loan acceptance efﬁciently and effectively with better accuracy than the traditional tree-based models.The model can also deal with a massive amount of business data and support corporations’decision-making process.

关键词： Business analytics decision trees machine learning business value decision making

Thermo-economic analysis of the performance of the combined system with evacuated tube collectors

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Clean Energy 2023年第2期7卷 242-252页

作者： Ghassan Fadhil Smaisim Salema K.Hadrawi Azher M.Abed Hasan Sh.majdi Ali Shamel Department of Mechanical Engineering Faculty of EngineeringUniversity of Kufa54001Iraq Nanotechnology and Advanced Materials Research Unit(NAMRU) Faculty of EngineeringUniversity of Kufa54001Iraq Refrigeration and Air-conditioning Technical Engineering Department College of Technical EngineeringThe Islamic UniversityNajaf54001Iraq Computer Engineering Department Imam Reza UniversityMashhadIran Department of Air Conditioning and Refrigeration Al-Mustaqbal University CollegeBabylon51001Iraq Department of Chemical Engineering and Petroleum Industries Al-Mustaqbal University CollegeBabylon51001Iraq Department of Chemistry Ardebil BranchIslamic Azad UniversityArdebilIran

Using combined cooling,heat and power systems can be an appropriate substitute for preventing emissions of pollutants and excessive consumption of fossil fuels.Utilizing renewable energy in these systems as a source of power generation can be an appropriate substitute for fossil-fuel-based systems.Therefore,in this paper,cogeneration cooling,heat and power systems based on gas-fired internal combustion engines with a solar-thermal system with evacuated tube collectors have been modelled and thermo-economic analysis has been done to compare fossil-fuel-based systems.The required rate of heat to supply the hot water is 50 kW.In the studied system,the internal combustion engine produces electrical energy.Then,the solar-thermal system with evacuated tube collectors and the gas-burning generator provide the thermal energy required by the studied building and the primary stimulus of the absorption chiller for cooling.In this study,two different scenarios are conducted in states considering simultaneous production systems and regardless of this environmental and thermo-economic analysis system.The results showed that the efficiency of the studied system was 60% in summer and 56% in winter.

关键词： combined cooling,heat and power thermo-economic analysis evacuated tube collectors environmental analysis solar-thermal energy

Modelling and optimization of combined heat and power system in microgrid based on renewable energy

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Clean Energy 2023年第4期7卷 735-746页

作者： Ghassan F.Smaisim Azher M.Abed Salema K.Hadrawi Hasan Sh.majdi Ali Shamel Department of Mechanical Engineering Faculty of EngineeringUniversity of Kufa54001Iraq Nanotechnology and Advanced Materials Research Unit(NAMRU) Faculty of EngineeringUniversity of Kufa54001Iraq Air Conditioning and Refrigeration Techniques Engineering Department Al-Mustaqbal University CollegeBabylon51001Iraq Refrigeration and Air-conditioning Technical Engineering Department College of Technical EngineeringThe Islamic UniversityNajafIraq Department of Chemical Engineering and Petroleum Industries Al-Mustaqbal University CollegeBabylon 51001Iraq Department of Chemistry Ardebil BranchIslamic Azad UniversityArdebilIran

Due to the short distance between the sources of production and consumption,microgrids(MGs)have received considerable attention because these systems involve fewer losses and waste less energy.And another advantage of MGs is that renewable energy sources can be widely used because these resources are not fully available and can provide a part of the required power.The purpose of this research is to model the MG considering the production sources of microturbines,gas turbines and internal combustion engines.Renewable energies such as wind turbines(WTs)and photovoltaic(PV)cells have been used to provide part of the required power and,because of the lack of access to renewable energy sources at all times,energy reserves such as batteries and fuel cells(FCs)have been considered.The power of the microturbine,gas turbine,internal combustion engine,FC and battery in this system is 162,150,90,100 and 225 kW,respectively.After modelling the studied system,optimization was done using the imperialist competitive algorithm to minimize production costs and provide maximum thermal and electrical loads.The maximum production power for PVs is equal to 0.6860 MWh and at this time this value for WTs is equal to 0.3812 MWh,in which case the excess electricity produced will be sold to the grid.

关键词： microgrid energy management system optimization optimal power flow combined heat and power sustainable development

A Secure Framework for Blockchain Transactions Protection

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Computer Systems Science & Engineering 2023年第5期45卷 1095-1111页

作者： Wafaa N.Al-Sharu majdi K.Qabalin Muawya Naser Omar A.Saraerh Department of Electrical Engineering Faculty of EngineeringThe Hashemite UniversityZarqa13133Jordan Department of Computer Science King Hussein School of Computing SciencesPrincess Sumaya University for TechnologyAmman11941Jordan

One of the most extensively used technologies for improving the security of IoT devices is blockchain technology.It is a new technology that can be utilized to boost the security.It is a decentralized peer-to-peer network with no central authority.Multiple nodes on the network mine or verify the data recorded on the Blockchain.It is a distributed ledger that may be used to keep track of transactions between several parties.No one can tamper with the data on the blockchain since it is unchangeable.Because the blocks are connected by hashes,the transaction data is safe.It is managed by a system that is based on the consensus of network users rather than a central authority.The immutability and tamper-proof nature of blockchain security is based on asymmetric cryptography and hashing.Furthermore,Blockchain has an immutable and tamper-proof smart contract,which is a logic that enforces the Blockchain’s laws.There is a conflict between the privacy protection needs of cyber-security threat intelligent(CTI)sharing and the necessity to establish a comprehensive attack chain during blockchain transactions.This paper presents a blockchain-based data sharing paradigm that protects the privacy of CTI sharing parties while also preventing unlawful sharing and ensuring the benefit of legitimate sharing parties.It builds a full attack chain using encrypted threat intelligence and exploits the blockchain’s backtracking capacity to finish the decryption of the threat source in the attack chain.Smart contracts are also used to send automatic early warning replies to possible attack targets.Simulation tests are used to verify the feasibility and efficacy of the suggested model.

关键词： Manuscript preparation typeset format