bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on Performance of Heritage Masonry Structures
Authors: Muthukumaraswamy Kamalakannan Sreenivas , Anandamurali Sravan Ashwin , Parthasarathy Arunachalam
Published: October 2023

A structural assessment study on the “Humayun Palace” in Tamil Nadu, a cultural heritage structure, constructed in the early 1700’s was done. Based on the original design documentation collected through records, a static analysis model of the building was generated. This structure is a 3-storey building and details of all the provisions from the slab system to the roof tiles were made. The results developed by these models, aimed at fully understanding the original design concept of the various members, as well as at evaluating their current static and seismic safety conditions, are reported in this paper. This analysis was examined using E-TABS software, whose geometric limitations lead to minor encumbrances. Some complex geometric façade features were approximated to convenience and overcome. The results of the analyses highlight safe conditions and good performance objectives in general, but for some important exceptions. The overall satisfactory performance may be attributed to the overdesigning with excessive safety factors carried out by builders of that century, enabling the structure to withstand conditions way past its intended life. However, the question as to how well the structure will hold good in the future is hypothetical. It is for the same reason that the Public Works Department has allocated nearly 96 crore rupees for the rehabilitation of the same. This investigation is synchronous with the objectives of the said rehabilitation project and has established an exhaustive analysis of the structural health of the structure.
A Review of PARP-1 Inhibitors: Assessing Emerging Prospects and Tailoring Therapeutic Strategies
Authors: Ramesh Soundarya , Almeida Shannon D , Hammigi Sameerana , Radhakrishna Govardan Katta , Sireesha Golla , Panneerselvam Theivendren , Vellingiri Shangavi , Kunjiappan Selvaraj , Ammunje Damodar Nayak , Pavadai Parasuraman
Published: October 2023

Eukaryotic organisms contain an enzyme family called poly (ADP-ribose) polymerases (PARPs), which is responsible for the poly (ADP-ribosylation) of DNA-binding proteins. PARPs are members of the cell signaling enzyme class. PARP-1, the most common isoform of the PARP family, is responsible for more than 90% of the tasks carried out by the PARP family as a whole. A superfamily consisting of 18 PARPs has been found. In order to synthesize polymers of ADP-ribose (PAR) and nicotinamide, the DNA damage nick monitor PARP-1 requires NAD+ as a substrate. The capability of PARP-1 activation to boost the transcription of proinflammatory genes, its ability to deplete cellular energy pools, which leads to cell malfunction and necrosis, and its involvement as a component in the process of DNA repair are the three consequences of PARP-1 activation that are of particular significance in the process of developing new drugs. As a result, the pharmacological reduction of PARP-1 may result in an increase in the cytotoxicity toward cancer cells.
A Novel Pedicle Screw Placement Surgery Based on Integration of Surgical Guides and Augmented Reality
Authors: Kong Huiyang , Wang Shuyi , Zhang Can , Chen Zan , Wu Zhanglei , Wang Jiayu
Published: October 2023

Background Augmented reality is a new technology that, when applied to spinal surgery, offers the potential for efficient, safe, and accurate placement of pedicle screws. This study investigated whether augmented reality combined with a guide board improved the safety and accuracy of pedicle screw placement compared to traditional freehand screw placement.

Methods Four trainers were divided into augmented reality navigation and freehand groups. Each group consisted of a novice and an experienced spine surgeon. A total of 80 pedicle screws were implanted. First, the AR group reconstructed the three-dimensional (3D) model and planned the screw insertion route according to the computed tomography (CT) data of L2 lumbar vertebrae. Next, the Microsoft HoloLens 2 was used to identify the vertebral model, and the planned virtual path was superimposed on the real cone model. Then, the screw was placed according to the projected trajectory. Finally, Micron Tracker was used to measure the deviation of screws from the preoperatively planned trajectory, and pedicle screws were evaluated using the Gertzbein–Robbins scale.

Results In the augmented reality group, the linear deviation of the experienced doctors and novices was 1.59 ± 0.39 and 1.73 ± 0.52 mm, respectively, and the deviation angle was 2.72 ± 0.61 and 2.87 ± 0.63 degrees, respectively. In the freehand group, the linear deviation of the experienced doctors and novices was 2.88 ± 0.58 and 5.25 ± 0.62 mm, respectively, and the deviation angle was 4.41 ± 1.18 and 7.15 ± 1.45 degrees, respectively. The screw placement accuracy rate was 97.5% in the augmented reality navigation group and 77.5% in the freehand group.

Conclusions Augmented reality navigation improves the accuracy and safety of pedicle screw implantation compared with the traditional freehand method and can assist inexperienced doctors in successfully completing the surgery.
Preservice teachers’ experiences of observing their teaching competencies via self-recorded videos in a personalized learning environment
Authors: Alamri Hamdan A. , Alfayez Abdulaziz A.
Published: October 2023

We investigated how preservice teachers observe and analyze their competencies through self-reflection and video-learning community strategies and how self-recorded videos influence their microteaching experience. We aimed to improve preservice teachers’ competencies in light of the Saudi National Professional Teaching Standards. Semi-structured interviews were conducted, and a thematic analysis was performed to extract themes identifying preservice teachers’ experiences and perceptions. The results indicated that the use of self-recorded videos can influence the microteaching experience and help identify development gaps, analyze weaknesses and strengths, and reflect upon them. The results showed that preservice teachers hold positive perceptions and experiences of self-recorded videos to improve their Saudi National Professional Teaching Standards competencies via self-reflection and video learning community. Furthermore, personalized learning principles benefit preservice teacher training programs through self-reflection and self-analysis without coach intervention. This study presents discussions, implications, and recommendations that are relevant to both researchers and practitioners.
Development of a prototype for a mobile application to monitor hypertension from ECG data
Authors: Alsalami Omar Mutab
Published: October 2023

Today, the use of personal digital assistants is increasing, especially due to the development of mobile devices. Especially at the medical level, their applications have grown a lot. Health cannot be left behind in this new digital age in using these new technologies. Given that the heart is the main organ of the cardiovascular system and is responsible for pumping blood throughout the body, it is not surprising that heart disease is the leading cause of death in Asian and Arabic countries, according to international health organizations operating under the World Health Organization. The average individual has no access to a device for home use and must rely on going to the doctor for a consultation and having to undergo the necessary procedure using pricy, specialized equipment. In this project, hardware and software were designed to produce a prototype device that can be purchased for a reasonable price, weighs little, and can be handled easily, enabling people to monitor their heart’s activity from the comfort of their homes. The core of the prototype is an AD8232 integrated circuit mounted on a SparkFun single-lead heart rate monitor-AD8232 card. When used with an Arduino card, serial communication with a computer, or Bluetooth with a smart device, this integrated circuit displays the graph and the person’s heart rate in beats per minute. The Android Studio platform was used to create the mobile app as well as the graphical personal computer version. 19 randomly chosen test volunteers’ heart rates and graphs were compared to the relevant ages listed in the literature.
Wide tuning of epsilon-near-zero plasmon resonance in pulsed laser deposited ITO thin films
Authors: Goswami Sumit , Sharma Ashwini Kumar
Published: October 2023

Oxygen vacancies in indium tin oxide (ITO) thin films provide a direct route to effectively tune the free electron density and thereby, controlling the epsilon-near-zero (ENZ) cut-off wavelength, the wavelength at which the real part of permittivity crosses zero of the permittivity axis. In this report, oxygen vacancies in pulsed laser deposited ITO thin films are systematically tuned using different background gases (O2, N2, Ar, and He). ENZ cut-offs are observed for the films deposited under He and Ar gases. In contrast, no such cut-offs are observed in the case of other two gases. An ITO thin film deposited under He gas exhibits deeper resonance signal than the one deposited under Ar gas. As expected, no such dip in the resonance spectra is observed for the films deposited under O2 and N2 gases. This observation is directly correlated to the change in the number of oxygen vacancies under different ambient gases. A modified transfer matrix method which incorporates surface roughness as an effective medium layer is developed to describe the experimentally observed resonance spectra numerically. Angular invariancy of ENZ plasmon resonance and the difference in absorption values for ITO films deposited under different gases is understood in terms of local field intensity enhancement factor. The study presented here will certainly be very useful in understanding the ENZ plasmon resonance phenomena as a whole. Additionally, ITO films deposited under an inert gas environment could be excellent material platforms for realizing several exotic ENZ applications.
Reconciling absence of vDVZ discontinuity with absence of ghosts in nonlocal linearized gravity
Authors: Dalmazi D
Published: October 2023

The modern massive gravity theories resolve a historical tension between the absence of the so called vDVZ mass discontinuity and the absence of ghosts via a fine tuned gravitational potential and a sophisticated screening mechanism. Those theories have originated the modern covariant bimetric models which are local, ghost free and cosmologically viable apparently, they contain a massive plus a massless graviton in the spectrum. It seems hard to solve the mentioned tension if we do insist in a model with a minimal number of degrees of freedom, with only one massive spin-2 particle in the spectrum, even if we allow nonlocal theories. Here we show that this problem can be circumvented in linearized nonlocal theories by the introduction of exponential terms with infinite derivatives. The model admits non linear completions via nonlocal quadratic terms in curvatures. We also investigate the role of the exponential factors in linearized models where the graviton remains massless and a mass scale is introduced via nonlocal terms, they are also ghost free and approach the Einstein–Hilbert theory as we go much above the introduced mass scale.
Operational risk assessment for hydroelectric generating units using multi-head spatio-temporal attention and adaptive fuzzy clustering
Authors: Liu Yi , Xu Yanhe , Liu Jie , Li Sifan , Cao Haiying , Chen Jianglong
Published: October 2023

A novel operational risk assessment method for hydroelectric generating units (HGUs) is presented in this article. First, a multi-head spatio-temporal attention gated network (MSTAGN) is proposed to establish an operation risk benchmark model for HGUs to reveal the intricate relationship between performance and its multiple influencing factors. In particular, MSTAGN learns complex interaction relationships among multiple influencing factors in both temporal and spatial dimensions and automatically extracts important features. Then, a nonlinear mapping function is constructed to extract the deviation of the current measured performance parameters from the predicted baseline performance parameters as the operation risk degree. On this basis, an adaptive fuzzy clustering algorithm is proposed to achieve a clear classification of the operating risk level for HGUs. The proposed method is applied in a HGU in Sichuan province, China. The results of comparative experiments demonstrate its viability and efficacy.
A deep learning method based on prior knowledge with dual training for solving FPK equation
Authors: Peng 彭 Denghui 登辉 , Wang 王 Shenlong 神龙 , Huang 黄 Yuanchen 元辰
Published: October 2023

The evolution of the probability density function of a stochastic dynamical system over time can be described by a Fokker–Planck–Kolmogorov (FPK) equation, the solution of which determines the distribution of macroscopic variables in the stochastic dynamic system. Traditional methods for solving these equations often struggle with computational efficiency and scalability, particularly in high-dimensional contexts. To address these challenges, this paper proposes a novel deep learning method based on prior knowledge with dual training to solve the stationary FPK equations. Initially, the neural network is pre-trained through the prior knowledge obtained by Monte Carlo simulation (MCS). Subsequently, the second training phase incorporates the FPK differential operator into the loss function, while a supervisory term consisting of local maximum points is specifically included to mitigate the generation of zero solutions. This dual-training strategy not only expedites convergence but also enhances computational efficiency, making the method well-suited for high-dimensional systems. Numerical examples, including two different two-dimensional (2D), six-dimensional (6D), and eight-dimensional (8D) systems, are conducted to assess the efficacy of the proposed method. The results demonstrate robust performance in terms of both computational speed and accuracy for solving FPK equations in the first three systems. While the method is also applicable to high-dimensional systems, such as 8D, it should be noted that computational efficiency may be marginally compromised due to data volume constraints.
Assessment of the probability of success and risking in hydrocarbon exploration: A case study from Zindapir Anticline, Sulaiman Foldbelt, Indus Basin, Pakistan
Authors: Ahmed S. , Nazeer A. , Habib W , Solnagi S H , Hameed S
Published: October 2023

Role of the statistical calculation is very important in petroleum exploration business. It is used to calculate the associated risk and determines the chances of geological success prior to drilling of an exploratory well in mapped prospect area. This manuscript is focusing on the geological modelling of Zindapir Anticline, Sulaiman Fold Belt, Indus basin, Pakistan using mainly based on the concept of probability developed by Coordinating Committee for Coastal and Offshore Geoscience Program (CCOP) in East and Southeast Asia in 2000. Study area comprises of Zindapir Anticline with two abandoned wells Well X-1 and Zindapir-1 which were drilled and declared as dry holes. Detailed geological modelling indicates that Zindapir structure is still virgin to flow hydrocarbons, and there are ample chances of compartments, which were developed as result of transpressional movement at the periphery of the structure. Interpreted seismic line also supports the presence of different compartments in structure. These compartments may host hydrocarbon, generated and migrated either from Bharti Syncline and Sulaiman Foredeep or generated by indigenous source rocks possibly deposited in the south of Zindapir-1 and Well X-1. Presence of trap, hydrocarbon charge and reservoir in Zindapir structure indicates there is better probability of success for hydrocarbons, and good chances for the development of traps because of transpressional movement. Traps may contain the hydrocarbon, possibly generated from Bharti Syncline in west and Sulaiman Foredeep in east whereas southern part of Zindapir Anticline was not considered, and northern part of Zindapir Anticline was mapped with very open grid size. Present seismic data is limited which is the major reason that due to poor probability of effective trap it is recommended to acquire additional seismic data for further detailed picture structure of Zindapir Anticline. An equation for the calculation of geological chances success for new development well is also proposed in this manuscript.
Optimization Design And Experimental Study of Self-oscillating Cavitating Jet Descaling Nozzle Based On Cleaning Operation
Authors: Huang You-quan , Lin Zhong-chao , Sun Jiang , Zhao Xu-yang , Zhang Pingan
Published: October 2023

The scale of tubing in polymer flooding and ASP flooding Wells is serious in Daqing oilfield. In order to improve the cleaning effect of tubing, the self-vibrating cavitation jet nozzle was developed and the cavitation jet technology was used to remove scale. In the design of nozzle structure, it is necessary to derive the basic relation that the structure of the oscillating cavity should satisfy when strong resonance is generated, and calculate the key length dimension L1 of the oscillating cavity. The numerical simulation method the different diffusion Angle α and diffusion length L3 nozzle wall under the condition of gas generation rate and axial velocity distribution, determine the optimum size of diffuser. The scale-removing performance test of cavitation jet verifies the performance of self-vibration cavitation nozzle and determines the optimal target distance and injection Angle. According to the reasonable dimension relation of the oscillating cavity when resonance occurs, the length L1 of the oscillating cavity when strong resonance occurs is calculated as 10.4mm. Use Fluent fluid calculation software painted wall gas generating rate, the relationship between the axial velocity curve, determine the diffusion Angle α to 30°, spread long L3 is 2.5 mm, jet cavitation effect is best. The descaling performance test shows that under the inlet pressure of 20MPa, the target distance of 15mm and the injection Angle of 60°, the effective cleaning area is the largest within 1s. The designed nozzle has a reasonable structure and efficient descaling performance.
Investigation and Application of Reversible Temporary Plugging Steering Agent for Acidification
Authors: Guan Gong-shuai , Wang Jing-wen , Shan Yong-zhuo , Tang Chao , Sun Wen-ping
Published: October 2023

In order to solve the problems of insolubility of conventional plant gum type solid steering agents and the need to return after stratified acidification to unblock the formation, two chemically reversible temporary plugging agents were developed in this paper. The variation of viscosity of liquid steering agent and the dissolution of particles of solid-liquid combination steering agent were evaluated indoors. The liquid steering agent single-pipe core blocking experiment and double-pipe core splitting rate experiment were carried out, and the indoor over-hole plate pressure measurement experiments of different types of steering agents were conducted. And the two steering agents were applied in the field. The results show that the viscosity of liquid steering agent can change with the pH value, showing the characteristics of becoming viscous in acid and decomposing in water, which can increase the injection pressure by 1.95MPa after plugging the core in the indoor experiment, and can increase the construction pressure by 1.4MPa in the field application. What’s more, the pressure of solid-liquid combination steering agent indoor over pore plate is 3 times of liquid temporary plugging agent, and the construction pressure can be increased by 3.0 MPa. Both of the above temporary plugging agents can be dissolved by themselves in the process of water injection after the measure, and the plugging of the reservoir can be released without returning to the drainage. Meanwhile, it can also meet the needs of different pressure difference layer section for diversion acidification.
Dessert Optimization and Oil Potential Analysis of M9 Block in W Oilfield
Authors: Yu Fu-ji
Published: October 2023

This article first explains the fine structure of the M9 block, and the encryption equal value line is finely constructed into a diagram to identify the micro -amplitude structure. Use the block drilling to complete the inner plane and vertical distribution statistics of the block. Essence Using the seismic section interpretation technology, multi -attributes and detailed portrayal of the broken layer, implement the overall structural characteristics and TEZHEN characteristics of the block, carry out multi -attribute analysis and research on the oil layer sandstone group, preferably seismic attributes sensitive to the development of sandstone, and obtain each through the calculation of the well -shaking combination calculation. Unit sandstone thickness quantitative prediction diagram, analyze the characteristics of the oil and water distribution of the block, combine the favorable positions of the well deployment, combine the characteristics of the structure, the break, and the sandy body distribution, and prefer the dessert area. The original large sedimentation law understands that the “single structure favorable oil control zone” is required to re -evaluate the high -risk zone, and combine the fine structure interpretation with the sand body reservoir prediction. Improve the success rate of the evaluation control well in the dessert area, and follow the deployment of the block well after the guidance.
Research and Practice of Heavy Oil Hydraulic Pump Lifting Technology in Bohai Bay K Oilfield
Authors: Zhang Zu-feng , Shao Yan-feng , Zhu Ying-bin , Li Ling-ling , Li Xue-wei , Li Guo-peng
Published: October 2023

In the early stage of heavy oil reservoir development in Bohai Bay K Oilfield, crude oil viscosity is high, conventional lifting processes have poor adaptability, and production energy consumption is high; Entering the stage of ultra-high water cut development, the company implemented carbon dioxide huff and puff, the difficulties in lifting matching brought about by the integrated wellbore requirements of injection and production, high gas-liquid ratio lifting, and enhanced corrosivity of the produced fluid. It conducted research on concentric dual/single pipe hydraulic lifting technology for heavy oil reservoirs, and conducted field practice. The research results and field practice show that the hydraulic pump lifting technology has good adaptability for both heavy oil sand production wells and heavy oil carbon dioxide huff and puff wells, effectively reducing the energy consumption of heavy oil lifting, significantly extending the pump inspection cycle of heavy oil sand production wells, significantly improving the lifting adaptability of carbon dioxide huff and puff wells, and has high promotion value in similar reservoirs and single wells.
Exploratory Test of Horizontal Drilling Plugs and Water Shutoff Technology in X Horizontal Gas Well
Authors: Wang Si-fan , Zhang An-kang , Hu Kai-Bin
Published: October 2023

In order to solve the problem that the tight gas X horizontal gas well could not be put into production due to the accumulation of fluid in the wellbore during the drainage stage after fracturation, based on the geological understanding of water flowing from the far end of the reservoir, and the actual situation of staged fractured with drillable bridge plug, water blocking has become the exploration direction of potential excavation and resuming production. Through the analysis of the type, structure, setting principle and unsealing principle of drillable bridge plug, put forward the technical idea of horizontal drilling plugs and mechanical water plugging. And determine the treatment method of drilling-grinding and fishing large inner diameter bridge plugs, and design the construction process. Moreover combined with theoretical calculation, the relationship between the debris carrying velocity and displacement in horizontal wells, the size of the debris and the angle of inclination was optimized. Besides that, the milling method that uses a wellhead rotating device to drive the drill pipe and grinding shoes for drilling and grinding was proposed. In the field test, successfully drill to the third large inner diameter bridge plug position according to the design requirements. And successfully put in the fishable bridge plug to achieve mechanical water blocking. After commissioning, the daily gas production volume reached 11000 m3/d. The test results show that: 1) It is feasible to use the wellhead rotating drive drill pipe and grinding shoes to drill and remove the steel drillable bridge plugs in the horizontal section of the horizontal well; 2) It is also feasible to use the fishable bridge to plug in the horizontal section of the horizontal gas well with drillable bridge plug staged fractured, and the plugging effect is good. In summary, it is shown that this technology test achieves the purpose of potential excavation and resuming production of the X horizontal gas well, which has good reference value.
Wetting Behavior of CO2 Droplets on Smooth Solid Surface: Molecular Simulation Perspective
Authors: Cao Heng-guang , Cao Xue-wen , Zhao Xiang-yang , Ma Yong-qing , Dong Mei-qin , Li Hao , Bian Jiang
Published: October 2023

The wettability of droplets on solid surfaces is important for accurately revealing the microscopic mechanisms of gas condensation nucleation and droplet growth. During the contact condensation of CO2 gas on the heat exchanger surface in the pressurized liquefied natural gas technology, the wettability of CO2 droplets on the heat exchanger surface directly affects the heat transfer thermal resistance of the heat exchanger, which then affects the heat transfer efficiency of methane and ethane in the heat exchanger. Therefore, molecular dynamics simulations were used to study the spreading process and wetting patterns of nanoscale CO2 droplets on different energy surfaces. The results show that as the potential well depth
ε
of the wall atoms increases, the intensity of the solid-liquid interaction increases and the corresponding surface energy increases accordingly, showing different droplet spreading rates and wetting characteristics. Unlike the interfacial characteristics of macroscopic droplets, there are significant fluctuations at the gas-liquid interface of droplets on the molecular scale, but microdroplets can still form a specific contact angle after spreading on different energy surfaces in a statistical sense, and this contact angle decreases with increasing intensity of solid-liquid interaction. The low-energy surface at potential well depths
ε
less than 266 J·mol-1 exhibits a CO2-phobicity, and the surface becomes CO2-philic as the potential well depth continues to increase. The trend of the contact angle of CO2 droplets affected by temperature is the same as that of the center-of-mass height, which characterizes the spreading morphology of CO2 droplets. As the temperature increases, the contact angle decreases due to the further spreading and wetting of droplets on different energy surfaces. As the CO2-philicity of the surface gets higher, the contact angle decreases to a greater extent.
Energy-load Matching and Shockwave Analysis of Electrical Explosion
Authors: Han Zhong-xing , Liu Ben , Guo Yan-bao , Wang De-guo , Lin Tao
Published: October 2023

Electrical explosion shockwave is a technique for inducing formation resonance by the interruption of formation pressure balance. By matching complex nonlinear influencing factors, this paper optimizes the engineering parameters and estimates the influence range of the shockwave. It achieves the objective of efficient shockwave acquisition and amplitude control. The test apparatus rapidly discharges the stored energy of various capacitance-voltage schemes, causing the load of various diameter-length structures to generate shaped shockwaves. By characterizing the discharge circuit and the shockwave signal, the energy and load matching was studied. Extraction of shockwave signal characteristics for decomposition and reconstruction analysis. The matching results indicate that the 10 MW loop oscillation is generated within 5 μs of discharge time, with the load diameter structure getting a major effect on the deposited energy. The 50 MPa shaped shockwave is generated in a 100 mm diameter region. And the peak pressure is influenced primarily by the load length structure and voltage scheme. The optimal load structure is D = 0.2 mm and L = 25 mm, controlling 2 to 5 times the input power’s enthalpy and increasing the voltage to create the shockwave more efficiently. The results of shockwave analysis indicate that the signal’s time-domain characteristics correspond precisely with its propagation path. The wavelet packet analysis indicates that the shockwave possesses a broad frequency and a high peak. The detection signal is composed of the principal shock wave, the radiation pressure wave, and the resonance error. The results provide theoretical basis for engineering application.
Research and Application of Intelligent Water Source Well Air Defense Pumping and Dry Burning Technology
Authors: Gao Bao-yuan , Li Zhao-hui , Zheng Wei-shi
Published: October 2023

The surface water injection technology for developing low permeability reservoirs comes from the water supply of water source wells. The groundwater resources in oil fields are limited, with high water consumption and a decrease in water level, lacking effective monitoring methods. In recent years, there have been frequent occurrences of unsafe waste of electrical energy due to dry burning during pumping in water source wells, which has seriously affected the normal water injection of oilfield formations. In order to prevent dry burning of water source wells by pumping air, research on intelligent air defense dry burning technology for water source wells has been carried out. The automatic pump stop alarm at low water level and the automatic pump start at high water level avoid the phenomenon of dry burning during pumping in the water source well, ensure the normal operation of the water source well, and ensure sufficient water injection from the source. Reduce employee labor intensity and achieve the goal of optimizing human resources. Associate the start and stop status of the water source well with the tank position of the water injection station to achieve automatic water distribution and inventory, achieve digital management and fine management, and achieve the goal of reducing costs and increasing efficiency, which has promotion value.
Removal of Amphiphilic Polymer from Tertiary Oil Recovery Wastewater Using Insoluble Cyclodextrin Polymer
Authors: Li Yuan , Zhang Ruian
Published: October 2023

The wastewater produced by amphiphilic polymer flooding is seriously emulsified and difficult to treat. In recent years, insoluble β-cyclodextrin (β-CD) polymers were widely employed in removal and utilization of organics with specific sizes and shapes. In this paper, a new type of host β -CD insoluble polymer (HCDP) was synthesized using β -CD with tetrafluoro-phthalonitrile (TFPN) as the crosslinker. A kind of guest amphiphilic polymer (GAP) was synthesized and the inclusion performance of HCDP to GAP was studied by viscosity method. Besides, The inclusion complexes of HCDP and GAP was regenerated using washing method and the inclusion capacity of the regenerated CDP was tested for five cycles. The results showed that GAP’ s apparent viscosity increased dramatically at about 800 mg/L and it showed linear relationship (R-square was 0.99902) with polymer concentration below 400mg/L, so GAP’ s concentration can be checked by viscosity method. HCDP can rapidly adsorb GAP in aqueous solutions and reach the adsorption equilibrium in about 20 minutes in the process of inclusion, and the maximum equilibrium adsorption amount of HCDP to GAP was about 150 mg/g. HCDP showed a strong recycling capacity. After five cycles of regeneration, the adsorption capacity did not significantly reduced, and the adsorption capacity remained above 140 mg/g. All the results prove that the new type of β-CD insoluble polymer can be used to encapsulate amphiphilic polymers in EOR wastewater, the study provides a new way for the resource utilization of amphiphilic polymers in EOR wastewater.
Study on Nozzle Structure of Hydraulic Jet Fracturing
Authors: Cai Meng , Cheng Xin-ying , Chen Xiu-hong , Zhu Chong-jia , Zhang Yan
Published: October 2023

In the process of hydraulic jet fracturing and perforation, fracturing fluid carrying sand is injected through annulus to fracture the pay zone. The numerical simulation analysis with the software of ANSYS-Fluent was applied aiming at the problem of low quality of fracturing fluid through the nozzle jet. By means of the analysis and comparison to some important structural parameters of the nozzle, the optimum jet quality through the nozzle was obtained. The research results showed. When the nozzle outlet diameter is from 4.5mm to 4.8mm; the length of the column is from 7mm to 12mm and the inlet radius of curvature is 9mm, the optimum jet quality of the nozzle can be obtained. The jet quality through the nozzle can be improved effectively through the analysis and optimization of the structure of the nozzle, which provides effective technical support for the hydraulic jet fracturing technology.
Failure Mechanism and Control Measures of Cu-CuSO4 Electrode in Saline Soil Environment
Authors: Li Chun-yu , Feng Xin-yuan , He Peng-cheng , Li Ben-quan , Li Chun-bao
Published: October 2023

Saline soil environment is widely distributed in western China, especially in Qaidam Basin. High salinity soil in Qaidam Basin has higher corrosion risk to metal pipelines. The Cu-CuSO4 electrode is used as the long-term reference electrode in the cathodic protection system of oil and gas pipeline. In saline soil environment, the Cu-CuSO4 reference electrode generally has a problem of excessive drift, which seriously affects the normal operation of cathodic protection system. The failure mechanism of the Cu-CuSO4 reference electrode in saline soil environment was demonstrated: soil ion pollution and drain drying caused potential drift. In view of the main factors affecting Cu-CuSO4 reference electrode drift in saline soil environment, measures such as adding packing material and setting up maintenance device were developed, and the field application effect was good. It provides a technical idea for prolonging the life of cathodic protection system in saline soil environment.
Research on Refracturing Technology of Ultra-low Permeability Fractured Oilfield
Authors: Li Ming-guo , Xuan Gao-liang , Han Wei , Zhang Hong-ni , Duan Mei-heng , Zhou Xue-ping
Published: October 2023

The development of ultra-low permeability reservoir in Daqingzi area, Qian an. With a long period of mining, the number of refractured wells is increasing year by year, but there is no benefit after fracturing. There is an urgent need for low-cost fracturing techniques to make refracturing more cost-effective. In this paper, on the basis of fully understanding reservoir physical properties, in-depth analysis of the major problems facing the refracturing of Daqingzi oilfield, and analysis of refracturing potential. Through field experiment, post-frac analysis and effect evaluation, the refracturing technology route suitable for this area is gradually explored. In this field experiment, the problem of underinjection was solved through the analysis and targeted transformation of injection wells. The average daily injection capacity of a single well was increased, injection pressure was reduced, the formation pressure of surrounding producing wells was restored to the original formation pressure, and the refracturing time of producing wells was reached, and the individual refracturing design of producing wells was carried out. In addition, post-frac analysis and effect evaluation were carried out. The results show that the injection-production relationship of the well group is improved obviously after the measures, the effect of increasing fluid and oil is remarkable, and the average fracturing cost per well is reduced. The new technology of holistic fracturing of injection and producing wells centered on injection well is defined. It provides technical support for increasing production and controlling cost of ultra-low permeability reservoir.
Multi-service access selection algorithm in 5G heterogeneous network
Authors: Wu Xiaoxin , Feng Chenwei , Zhong Zhenzhe
Published: October 2023

As advancements occur in new wireless communication technology, varieties of network forms coexist and integrate, gradually forming a heterogeneous wireless network environment covered by various wireless networks simultaneously. Owing to disparities in wireless access technologies, network selection needs to consider various factors. Therefore, this paper proposes an access selection scheme using Multi-Attribute Decision-Making (MADM). Considering the diversity of user services, each attribute’s subjective and objective weight is respectively calculated by Analytic Hierarchy Process (AHP) and Standard Deviation (SD) for network service quality, user preference, and available load. Combined with utility functions, the synthetic assessments of evaluated networks are obtained. The results of the simulation indicate that the algorithm combines user preference and service characteristics to effectively select the appropriate access network. At the same time, load balancing is realized to some extent.
A Zero-trust Access Control Scheme Based on CPABE
Authors: Wu Kehe , Jiang Xiaochen , Zhang Jiyu , Zhu Yajing , Zhou Yandong , Wu Jiao , Li Shu
Published: October 2023

The introduction of new power terminals has improved the efficiency of the new power system, but it has also brought new risks. It is important to research ways to prevent cloud resources from unauthorized access by these terminals. To address this issue, an access control scheme was proposed based on Ciphertext-Policy Attribute-Based Encryption (CPABE) technology, which can encrypt cloud resource information and make access control fine-grained. We also combine the SM9 algorithm to reduce the key management burden of traditional CPABE technology and introduce a zero-trust mechanism to provide a higher level of security protection for the subsequent access control process of the terminal. Additionally, we prove the correctness and analysis of the attack, which can be resisted by the proposed scheme, demonstrating its feasibility and security. Finally, a comparison was made between our scheme and other CPABE schemes. Our scheme is proven to perform better in performance.
Estimation of combinatoric background in seaquest using an event-mixing method
Authors: Pate S.F. , Pun A. , Hossain M.F. , Nagai K. , Aidala C.A. , Ayuso C. , El Fassi L. , Geesaman D.F. , Hague T.J. , Kinney E.R. , Lorenzon W. , Nakano K. , Reimer P.E. , Scott M.B.C. , Towell R.S.
Published: October 2023

All experiments observing dilepton pairs (e.g. e
+
e
-,
 μ
+
μ
-) must confront the existence of a combinatoric
background caused by the combining of tracks not arising from the
same physics vertex. Some method must be devised to calculate and
remove this background. In this document we describe a particular
event-mixing method relying on many of the unique aspects of the
SeaQuest spectrometer and data. The method described here
calculates the combinatoric background with correct normalization;
i.e., there is no need to assign a floating normalization factor
that is then determined in a subsequent fitting procedure. Numerous
tests are applied to demonstrate the reliability of the method.
Kohn–Sham computation and the bivariate view of density functional theory
Authors: Lammert Paul E
Published: October 2023

Informed by an abstraction of Kohn–Sham (KS) computation called a KS machine, a functional analytic perspective is developed on mathematical aspects of density functional theory. A natural semantics for the machine is bivariate, consisting of a sequence of potentials paired with a ground density. Although the question of when the KS machine can converge to a solution (where the potential component matches a designated target) is not resolved here, a number of related ones are. For instance: can the machine progress toward a solution? Barring presumably exceptional circumstances, yes in an energetic sense, but using a potential-mixing scheme rather than the usual density-mixing variety. Are energetic and function space distance notions of proximity-to-solution commensurate? Yes, to a significant degree. If the potential components of a sequence of ground pairs converges to a target density, do the density components cluster on ground densities thereof? Yes, barring particle number drifting to infinity.
Breccia for Diversion Tunnel Construction at Bener DAM in Purworejo, Central Java, Indonesia: Fragments, Matrix, RMR
Authors: Triristanto E R , Husein S , Alfarobi M Y Y
Published: October 2023

This study aimed to explain the detailed engineering geology investigation which has breccia geological units on Diversion Tunnel at Bener Dam, Purworejo Regency, Central Java Province. The investigation includes geological conditions both breccia fragment and matrix, to Rock Mass Rating (RMR) values each unit. The data were taken from face mapping tunnel with interval 10 meters at inlet 1-390 and 841-865 meters. The findings showed that geological engineering units consisted of Monomict Breccia. The geological units can be divided into geological engineering; Monomict Breccia Matrix (RMR 72-92), Polymict Breccia Matrix (RMR 82), Andesite Fragmen (RMR 52-62), and Tuff Fragmen (RMR 79-84). The discovery of Andesite and Tuff Fragments needs to be handled differently than Monomict Breccia or Polymict Breccia. Andesite Fragment unit with discontinuity of sheeting joint requires rock bolt reinforcement to be installed perpendicular to the discontinuity plane. While the dominant unit is the Tuff Fragment which has a UCS value of 5-7 MPa, it is not recommended to use the blasting excavation method even though it has an RMR value of 79-84.
Empirical Approach For Preliminary Support and Excavation Method Design Based On Engineering Geological Study Of Mbay Dam Diversion Tunnel
Authors: Purba D W E , Amijaya D H
Published: October 2023

This paper presents excavation methods and support systems in the diversion tunnel of the Mbay Dam, East Nusa Tenggara, Indonesia, based on rock mass quality ratings. The rock mass quality was classified through geological surveys, core drilling evaluations, and laboratory tests. The results showed that the lithology along the tunnel alignment was pyroclastic breccia. Using the Rock Mass Rating (RMR) classification system, which was the single classification at the time of designing the Mbay Dam Diversion Tunnel, the pyroclastic breccia rock mass was classified III and IV (fair and poor). Meanwhile, according to the Q-System classification, the second classification used, pyroclastic breccias were also classified as fair and poor. Therefore, according to the RMR classification, the recommended excavation methods were top heading and bench. Support systems suitable for rock mass quality in the Mbay Dam diversion tunnel were rock bolt, wire mesh, shotcrete, and steel sets, with different variations and types depending on the rock mass class and classification used.
Greenhouse Gasses Emission from Coal Mining Operation in North Kalimantan, Indonesia
Authors: Lusantono O W , Anggara F , Amijaya D H , Kusumaningsih D A
Published: October 2023

Greenhouse gasses (GHG) are gases that could trap heat in the atmosphere and mainly made up of carbon dioxide (CO¬2¬) and methane (CH4). Coal is still one of the primary energy sources in several countries such as South Africa (71%), China (57%), Australia (30%), and Indonesia (44%). Therefore, coal mining operation is indicated as one of the biggest GHG contributor in the world. However, coal as commodity also indicated emitting GHG emission sequentially but its pathways are still debatable. GHG emission from coal mainly stated as an emission factor on both CO2 and CH4 because of coal combustion and/or existing gas in the coal bearing strata. The study of GHG emission or so-called Carbon Emission has been done based on several regions, coal rank, and condition. This study focuses on identify and projecting the GHG emission based on coal mining operation plan in North Kalimantan Province, Indonesia. This study aims to identify and adds more broader perspective about GHG emission from coal mining. The GHG emission estimation is based form Tier 1 IPCC Calculation method and estimated from a different scenario of production along the year. The GHG emission in this study estimated from fuel combustion and fugitive emission. The total emission estimated from this study was 1.31 × 10-02 kg CO2eq / kg coal.
Rock Mass Classification for Support System Design and Stand-up Time of Asahan 3 Hydroelectric Power Plant Tunnel (STA 7+085 - STA 7+717)
Authors: Rochmadi A , Karnawati D
Published: October 2023

This Engineering geology research on rock mass classification to determine the support system’s design and stand-up time at the Asahan 3 hydroelectric tunnel STA 7+085 – STA 7+717 has not been thoroughly carried out in detail. This study aims to estimate the support requirements. Rock mass classification is determined through core drill observations and then analyzed by Q-system and RMR methods. The results show that the rock mass at the tunnel depth elevation consists of sandstone with good quality based on RMR and Q-system. Based on the Q system classification, good quality sandstone is obtained. Based on RMR, the suggested support system is shotcrete in the crown and rockbolt. Meanwhile, a rock bolt is the appropriate support system based on the Q-system. The use of an RMR based support system is recommended because it provides a higher level of security with the addition of shotcrete. The tunnel stand-up time is 2,200 - 2,700 hours based on RMR. The result of this research is expected to be applied in other tunnel construction having similar engineering geological condition.
Static and Pseudo Static Analysis of Embankment Slope Stability of Bener Dam, Purworejo Regency, Central Java
Authors: Ranysakol Thuon
Published: October 2023

The Bener Dam is considered as one of the largest rock-fill dams in Indonesia. This dam will impact the inundation area of three main villages in the Wonosobo and Purworejo regency. Since this zoned embankment dam consists of rock-fill and the core material, the stability of the dam slope has to be done to ensure that the dam is stable against any failures including the seismic effects. Moreover, the seismic coefficient in the study area in the seismic analysis of the large dam slope is needed to be used in the analysis which is not yet done from the previous studies. This paper presents the analysis of the embankment slope stability of the Bener dam under static condition and pseudo static condition. The analysis takes into account the end stage of construction, the steady-state stage, and rapid drawdown stage. The results of utilizing the Finite Element Method to analyse the slope stability demonstrates that the dam embankment slopes are stable under static and seismic stress conditions in all the reservoir condition stages. After applying the seismic loading, the result of safety factor of slope stability is reduced while the rapid drawdown stage has the lowest safety factor.