Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Social and Behavioral Sciences (657593)
- Arts and Humanities (572358)
- Law (543157)
- Education (382104)
- Medicine and Health Sciences (324682)
-
- Physical Sciences and Mathematics (292364)
- Life Sciences (256080)
- Engineering (195844)
- History (181336)
- Business (148818)
- Higher Education (142709)
- Anthropology (115942)
- Religion (109809)
- Archaeological Anthropology (96468)
- Communication (89124)
- Sociology (86262)
- Library and Information Science (80016)
- United States History (77482)
- Medical Specialties (76798)
- Psychology (73543)
- Computer Sciences (62962)
- Public Affairs, Public Policy and Public Administration (62240)
- Earth Sciences (59319)
- Creative Writing (57898)
- Public Health (55573)
- Environmental Sciences (52324)
- English Language and Literature (47450)
- Economics (46662)
- Educational Administration and Supervision (46470)
- Music (45876)
- Institution
-
- University of South Florida (163039)
- University of New Mexico (139108)
- University of Nebraska - Lincoln (114003)
- Kenyon College (112912)
- University of Montana (98218)
-
- University of Mississippi (94101)
- University of New Hampshire (79651)
- Brigham Young University (72144)
- Georgia Southern University (61490)
- Eastern Illinois University (57888)
- Utah State University (57314)
- Mississippi State University (54507)
- Western Michigan University (52950)
- University of Kentucky (52306)
- Murray State University (50459)
- Purdue University (50068)
- University of Colorado Law School (47444)
- Louisiana State University (45135)
- Brigham Young University Law School (43600)
- University of Dayton (43225)
- Western Kentucky University (43085)
- Villanova University Charles Widger School of Law (42711)
- California Polytechnic State University, San Luis Obispo (42483)
- University of Central Florida (41626)
- Chulalongkorn University (37308)
- San Jose State University (36962)
- University of Alabama at Birmingham (35953)
- University of Northern Iowa (35946)
- Yale University (33787)
- Missouri University of Science and Technology (33636)
- Keyword
-
- Newspaper (47336)
- Latin America (31531)
- Press release; media release; press statement; news media information (30839)
- Spanish (30833)
- History (30077)
-
- University of New Mexico (29735)
- UNM (29638)
- LADB (29608)
- LAII (29608)
- Latin American and Iberian Institute (29608)
- Humans (29363)
- Education (28960)
- United States (21344)
- Student newspaper (19956)
- Newsletter (19706)
- EIU (19627)
- Georgia Southern University (18903)
- Newspapers (18264)
- Deaf culture (17102)
- Hearing impaired (17091)
- Pastoral care of people with disabilities (17060)
- Church work with the deaf -- Catholic Church (17052)
- Deaf -- Periodicals (17043)
- Athletics (16848)
- Marriage (16178)
- Poetry (15531)
- Students (15110)
- Higher education (14576)
- COVID-19 (14393)
- Female (14195)
- Publication Year
-
- 2026 (101404)
- 2025 (156134)
- 2024 (192536)
- 2023 (162648)
- 2022 (167689)
-
- 2021 (195838)
- 2020 (169183)
- 2019 (165312)
- 2018 (169410)
- 2017 (160776)
- 2016 (159498)
- 2015 (146205)
- 2014 (135644)
- 2013 (129979)
- 2012 (124605)
- 2011 (108178)
- 2010 (103548)
- 2009 (95636)
- 2008 (92722)
- 2007 (79179)
- 2006 (74488)
- 2005 (70091)
- 2004 (71227)
- 2003 (58603)
- 2002 (64451)
- 2001 (55051)
- 2000 (58447)
- 1996 (62276)
- 1992 (52971)
- 1990 (53641)
- Publication
-
- Four Valleys Archive (90475)
- Theses and Dissertations (74001)
- Faculty Publications (45619)
- Electronic Theses and Dissertations (35895)
- University of Montana News Releases, 1928, 1956-present (30910)
-
- Faculty Scholarship (25288)
- Dissertations (23668)
- The Auk (22791)
- Documents (21830)
- Theses (21677)
- Articles (19999)
- Browse All News (19555)
- Walden Dissertations and Doctoral Studies (19539)
- Masters Theses (18625)
- Master's Theses (18420)
- Chulalongkorn University Theses and Dissertations (Chula ETD) (15281)
- Session Laws 1951-2000 (15051)
- NotiSur (13785)
- Faculty, Staff and Student Publications (13688)
- Hillsborough County Marriage Records (13681)
- University of Mississippi News (13497)
- Obituaries (13320)
- The Murray Ledger & Times (13003)
- Sheet Music Collection (12976)
- Michigan Law Review (12806)
- University of Montana Course Syllabi (12469)
- Honors Theses (12162)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (11863)
- Condor (11821)
- Defensive Publications Series (11692)
- Publication Type
Articles 103621 - 103650 of 5149878
Full-Text Articles in Entire DC Network
Multivariate Optimization Of Nonlinear Response Functions Using Central Composite Design, Hussein M. Hussein, Bassma H. Elwakil, Esraa Abdelhamid Moneer, Sara H. Akl, Yahya H. Shahin
Multivariate Optimization Of Nonlinear Response Functions Using Central Composite Design, Hussein M. Hussein, Bassma H. Elwakil, Esraa Abdelhamid Moneer, Sara H. Akl, Yahya H. Shahin
Almaaqal Journal of Sustainability and Emerging Technology
This study addresses critical challenges in multivariate optimization by: (1) developing efficient strategies for optimizing nonlinear response functions in high-dimensional parameter spaces, (2) quantifying comparative performance of traditional versus statistical design methodologies, (3) establishing mathematical frameworks for parameter interactions, and (4) validating results through comprehensive statistical analysis. A dual-phase optimization framework combined One-Variable-At-a-Time (OVAT) screening with Central Composite Design-based Response Surface Methodology (CCD-RSM). Five parameters were evaluated using rotatable CCD (α= 2.378) with 50 design points. Statistical analysis included analysis of variance (ANOVA), regression modeling, interaction quantification, and cross-validation. CCD-RSM demonstrated superior performance with model predictability improving from …
Machine Learning Framework For Automatic Classification Of Nano-Seismic Signals Preceding Earthquakes, Ghada Ali, Ali G. Hafez, Sayed Hasaneen, Hamed Nofel, Nabeel Al-Atwan, Ahmed Mohamed
Machine Learning Framework For Automatic Classification Of Nano-Seismic Signals Preceding Earthquakes, Ghada Ali, Ali G. Hafez, Sayed Hasaneen, Hamed Nofel, Nabeel Al-Atwan, Ahmed Mohamed
Almaaqal Journal of Sustainability and Emerging Technology
Nano-seismicity preceding earthquakes has many applications in fault prediction, in structure health monitoring, and in enhancing fault and source parameter determination. Not all earthquakes are preceded by these precursors; therefore, there is a need to identify P-wave arrivals that are preceded by these nano signals, which will eliminate errors in P-wave arrival timing. The current work introduces topologies capable of automatically categorizing the arrivals with nano-seismic precursors. The proposed methods are trained on datasets extracted from stations belonging to Egyptian National Seismic Network (ENSN). These records contain both P-wave arrivals preceded by such nano precursors and other records without these …
Optimizing Bioethanol Production Using Design Of Experiments For Sustainable Biofuel Development, Hussein M. Hussein, Yahya H. Shahin, Ihab A. Moneam
Optimizing Bioethanol Production Using Design Of Experiments For Sustainable Biofuel Development, Hussein M. Hussein, Yahya H. Shahin, Ihab A. Moneam
Almaaqal Journal of Sustainability and Emerging Technology
This study presents a statistically optimal approach for bioethanol production from sugarcane bagasse (SCB) using alkaline pretreatment, enzymatic hydrolysis, and fermentation processes. To maximize cellulose yield, four extraction parameters—solvent type, concentration, temperature, and time—were optimized using a Taguchi statistical model. The Taguchi-optimized extraction yields 11.3% increased cellulose recovery relative to cellulose recovered via non-optimized extraction methods (i.e., alkaline treatment with 6% NaOH at 90 °C for 3 hours). This yielded 45.20% cellulose (w/w), with 37.80% weight loss (predicted weight loss was 36.94%). Statistical analysis of extraction results verified solvent type (p = 0.0022) and temperature (p = 0.0007) to be …
A Smart City Transformation Survey: Using Intelligent Buildings To Promote Smart Cities, Salma A. Alhashimi, Majid A. Alwan, Ali N. Aliedani
A Smart City Transformation Survey: Using Intelligent Buildings To Promote Smart Cities, Salma A. Alhashimi, Majid A. Alwan, Ali N. Aliedani
Almaaqal Journal of Sustainability and Emerging Technology
The challenges of urbanization have been greatly aided by the integration of cutting-edge technology into smart buildings and cities. In smart cities and buildings, machine learning and the Internet of Things are essential for boosting sustainability, increasing safety, and optimizing resource use. In order to enable more effective, connected, and comfortable living in urban settings, this work has introduced the relationship between creative technology and buildings. It also discusses the regulatory frameworks for smart cities and emphasizes the importance of standardization in this regard.
Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere
Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere
Turkish Journal of Chemistry
Gold is abundant in nature, however, precise and reliable analytical methods for its detection are required stemming from its increasing prevalence in environmental, biological, and industrial systems, as well as the growing interest in understanding its function in living organisms and its effects on human health. This study investigates the use of biogenically synthesized silver nanoparticles (AgNPs) for the preconcentration and determination of gold ions prior to determination by UV-Vis spectrophotometry. AgNPs were synthesized by reducing silver nitrate through the use of an apricot kernel extract as both reducer and stabilizer agent. The colloidal yellowish AgNPs interacted with gold ions, …
A Novel Approach On Digital Pentapartitioned Neutrosophic Topological Structures In Bpˆ˙A˚Lgebra, R. Shalini, G. Sindhu, S.S. Surekha
A Novel Approach On Digital Pentapartitioned Neutrosophic Topological Structures In Bpˆ˙A˚Lgebra, R. Shalini, G. Sindhu, S.S. Surekha
Neutrosophic Sets and Systems
No abstract provided.
An Intelligent Soft Computing-Oriented Strategy For Managing Global Sustainability Issues In Dynamic Environments, Walaa M. Sabry
An Intelligent Soft Computing-Oriented Strategy For Managing Global Sustainability Issues In Dynamic Environments, Walaa M. Sabry
Neutrosophic Sets and Systems
No abstract provided.
Transnational Mass Tort Litigation: A Proposal For An International Court Of Civil Justice, Maya Steinitz
Transnational Mass Tort Litigation: A Proposal For An International Court Of Civil Justice, Maya Steinitz
Faculty Scholarship
This chapter argues for the creation of an International Court of Civil Justice for transnational mass tort cases. It considers the challenges of adjudicating cross-border mass torts along with the incentives and feasibility of a new international court. Drawing upon case studies including the Bhopal disaster, litigation surrounding the devastation of the Ecuadorian rainforest, and the attempts to sue over human rights abuses in Nigeria, the chapter demonstrates that the world's legal systems were not designed to solve these kinds of complex cases, and the absence of mechanisms to ensure coordination means that victims try, but fail, to find justice …
Automatic Guitar Transcription Of Polyphonic Music, Ritwik Patil
Automatic Guitar Transcription Of Polyphonic Music, Ritwik Patil
Master's Theses
Transcribing guitar music automatically is a complex task due to polyphonic overlap, tuning variations, and diverse playing techniques. Current transcription systems focus on identifying note pitches and timing while ignoring performance techniques that describe how the notes are played, treating guitar recordings as generic polyphonic audio and producing MIDI-like outputs that lose important information about articulation and style. To address these challenges, we propose an end-to-end transformer model for automatic guitar transcription. The system uses a T5-based encoder-decoder architecture that processes the Constant-Q Transform (CQT) of stereo audio input. The stereo representation helps separate individual guitar parts within a mix …
Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee
Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee
Turkish Journal of Chemistry
Paclitaxel (Pac) is an important anticancer bioactive compound, and the availability of an accurate and robust analytical method for its quantification is of utmost importance. In this investigation, a novel, direct, and reliable spectrophotometric method has been proposed for the estimation of Pac via a complex formation reaction with osmium (Os). The method was based on the reaction of Pac with Os tetroxide, which produced a yellowish-brown complex. The resulting complex is soluble in water and displays a maximum absorption peak at 482 nm. The reaction conditions, including reactant concentration, pH, temperature, and reaction time, were optimized to obtain the …
Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Synthesis, Characterization, And Theoretical Study Of New Cocrystals And Charge-Transfer Compounds, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Turkish Journal of Chemistry
This study used single-crystal X-ray diffraction, elemental analysis, infrared (IR) spectroscopy, theoretical nuclear magnetic resonance (NMR), and theoretical ultraviolet spectroscopy to characterize 3 newly synthesized crystalline compounds. Additionally, the nonlinear optical, highest occupied molecular orbital energies, lowest occupied molecular orbital energies, band gap, molecular electrostatic potential, and thermodynamic parameters of the 3 crystalline compounds were examined. The strong correlation between experimental IR spectra and theoretical NMR chemical shifts confirmed the accuracy of computational predictions. The molecular formulas of the 3 newly synthesized crystalline compounds, each containing different ligand molecules, were: C8H14O4·2(C6H4N2), C5H7N2·NCS, and Ni(CN)4·2(C5H7N2)·2(H2O) for compounds 1, 2, and 3, …
Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy
Α-Glycosidase Activity Of Novel Coumarin–Triazole–Coumarin Dyads, Ersi̇n Şi̇ri̇n, Esra Sevi̇mli̇, Gökçe Seyhan, Burak Barut, Yunus Kaya, Baybars Köksoy
Turkish Journal of Chemistry
Novel coumarin–triazole–coumarin dyads were synthesized and characterized, and their α-glycosidase inhibitory activities were evaluated spectrophotometrically. Compound 4e exhibited the most pronounced inhibitory effect, with an IC50 value of 38.98 ± 0.77 μM. The IC50 values for 4d and 4a were 93.55 ± 1.70 μM and 95.04 ± 3.55 μM, respectively. The Lineweaver–Burk plot showed that 4e inhibited α-glycosidase in a mixed type. In addition, the Ki value obtained from the Dixon plot was 19.95 ± 0.15 μM for α-glycosidase.
Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz
Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz
Turkish Journal of Chemistry
This study investigates the extraction behavior of Y³⁺ ions using a Multi-Dropped Liquid Membrane (MDLM) system that employs di(2-ethylhexyl) phosphoric acid (D₂EHPA) as the carrier ligand. The focus is on the system’s ability to transport ions between aqueous phases selectively. The extracted complex was analyzed spectrophotometrically via ultraviolet–visible (UV–Vis) measurements after complexation with 0.05% Arsenazo III. The aim of this study was to determine the influence of the optimum D₂EHPA carrier concentration, together with the pH and temperature conditions of the donor and acceptor phases, on the system’s extraction performance. Accordingly, a series of extraction experiments was performed at different …
Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay
Utilization Of Dual Catalysts For High-Yield Boron Nitride Nanotube Synthesis Via Chemical Vapor Deposition, Şaban Kalay
Turkish Journal of Chemistry
The direct synthesis of boron nitride nanotubes (BNNTs) via chemical vapor deposition (CVD) in high-temperature furnaces remains highly challenging due to difficulties in optimizing key experimental parameters such as synthesis temperature and catalyst composition. These challenges often result in uncontrolled growth behavior, adversely affecting the quality and yield of the BNNTs. In this study, colemanite was effectively utilized as a boron source for the high-yield synthesis of directionally aligned BNNTs. The synthesis was carried out using a CVD method that used a dual-catalyst system comprising Fe2O3 and MgO in conjunction with a silicon carbide template under high-temperature conditions. The resulting …
Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat
Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat
Turkish Journal of Chemistry
This study highlights the potential of organometallic carbonyl complexes as selective markers for biomolecules, enabling sensitive infrared (IR) detection. The regio- and stereoselective coupling of N-acetylhistamine, a histidine analogue, with the precursor complex 1 [Fe(CO)₃(1,4-η⁵-N-pyridiniocyclohexa-1,3-diene)] BF₄ affords the labeled complex 3 [Fe(CO)₃(1,4-η⁵-N-acetylhistaminocyclohexa-1,3-diene)]. X-ray diffraction (XRD) confirms the exo stereochemistry and reveals a rigid, well-defined architecture. IR and 1H nuclear magnetic resonance spectroscopic studies combined with IR-monitored acid–base titration demonstrate the complex’s stability in aqueous media between pH 5 and 8, alongside a modest increase in basicity relative to the free ligand. These findings establish the Fe(CO)₃ moiety as a robust …
State Of California Cannabis Reporting, University Of Mississippi – National Center For Cannabis Research And Education
State Of California Cannabis Reporting, University Of Mississippi – National Center For Cannabis Research And Education
California
No abstract provided.
Incidental Cardiac Metastasis In Breast Carcinoma, Yaomin Chen, Haibo Wang, Zhiyan Fu, Ellen Elizabeth Connor
Incidental Cardiac Metastasis In Breast Carcinoma, Yaomin Chen, Haibo Wang, Zhiyan Fu, Ellen Elizabeth Connor
School of Medicine Faculty Publications
Background and Clinical Significance: Metastatic breast cancer is a major global health burden, with common metastatic sites including the bones, lungs, liver, and brain. Cardiac metastasis is rare and often clinically silent, leading to underdiagnosis. Recognizing cardiac involvement, even when asymptomatic, is important for understanding the full extent of disease and ensuring optimal patient care. Case Presentation: We report the case of a woman with advanced breast carcinoma who showed no clinical or imaging evidence of cardiac involvement throughout the course of her illness. Following her death from progressive metastatic disease, an autopsy revealed metastatic carcinoma infiltrating the myocardium and …
Investigating Surface-Borehole Transient Electromagnetic Responses From Veined Orebodies Considering Induced Polarization Effects, Li Jianhui, Wang Yao, Wang Wenchuang, Xie Shaojian, Zhu Siwei
Investigating Surface-Borehole Transient Electromagnetic Responses From Veined Orebodies Considering Induced Polarization Effects, Li Jianhui, Wang Yao, Wang Wenchuang, Xie Shaojian, Zhu Siwei
Coal Geology & Exploration
Objective The observational data derived using the surface-borehole transient electromagnetic (TEM) method tend to feature complex curve morphologies, a problem posing significant challenges to data processing and interpretation. This study aims to ascertain the mechanisms behind the generation of such complex responses using forward modeling.Methods Using the vector finite element-based spectral method and the Cole-Cole model, this study developed a 3D forward modeling technique incorporating the induced polarization (IP) effect. By constructing a typical theoretical model of low-resistivity veined orebodies, it systematically analyzed the electromotive force (EMF) responses excited by transmitter loops at different orientations. Results and Conclusions The …
Coal Body Structure Identification Method Based On Bayesian-Optimized Cnn-Bilstm-Attention, Bian Huiyuan, Ji Jiajun, Duan Chaowei, Zhou Jun, Li Kun, Ma Yuhan
Coal Body Structure Identification Method Based On Bayesian-Optimized Cnn-Bilstm-Attention, Bian Huiyuan, Ji Jiajun, Duan Chaowei, Zhou Jun, Li Kun, Ma Yuhan
Coal Geology & Exploration
Background Coal-bearing basins contain primary and tectonically deformed coals due to multistage tectonic deformations. However, the gas-bearing properties of coal seams differ significantly due to varying pore and fracture densities, permeability, and mechanical properties. This makes coal structure assessment critical to coalbed methane (CBM) exploration and production. Objective and Method To enhance the accuracy and intelligence of coal structure identification, this study constructed a CNN-BiLSTM-Attention hybrid model that integrated a Bayesian optimization strategy. This model allowed for efficient fusion and representation of multi-scale log data by combining the local feature extraction capability of the convolutional neural network (CNN), the temporal …
Self-Adaptive Inverse Wavefield Transform And Derived Pseudo-Wavefield Characteristics Under Roadway-Borehole Observation Of Transient Electromagnetic Data, Fan Kerui, Guo Jianlei, Wang Ruoyu, Zhuang Ming, Fan Fangze, Xu Sheng, Zhao Wentao
Self-Adaptive Inverse Wavefield Transform And Derived Pseudo-Wavefield Characteristics Under Roadway-Borehole Observation Of Transient Electromagnetic Data, Fan Kerui, Guo Jianlei, Wang Ruoyu, Zhuang Ming, Fan Fangze, Xu Sheng, Zhao Wentao
Coal Geology & Exploration
Objective To address the challenge of detecting aquifers outside the roadway excavation contour, this study combined the close-range detection via roadway-borehole transient electromagnetic (TEM) method with the wavefield transform. This will help simultaneously receive detection signals in front of the mining face and outside the roadway excavation contour while also highlighting the boundary information of aquifers. Moreover, to obtain a pseudo-wavefield featuring both reasonable kinematic characteristics and high sensitivity to changes in the electrical structures of strata, this study proposed a self-adaptive algorithm of inverse wavefield transform, thereby improving the accuracy and efficiency of the inverse wavefield transform of roadway-borehole …
Performance And Migration Path Tracing Of Magnetic Grouts For Fractured Rock Masses, Shang Hongbo, Wang Hao, Wang Xiaodong, Qiao Wei, Wang Tiantian, Sun Junqing, Sun Jie
Performance And Migration Path Tracing Of Magnetic Grouts For Fractured Rock Masses, Shang Hongbo, Wang Hao, Wang Xiaodong, Qiao Wei, Wang Tiantian, Sun Junqing, Sun Jie
Coal Geology & Exploration
Objective For coal mining areas in the middle reaches of the Yellow River basin, sealing mining-induced fractures via grouting serves as an effective approach to preventing water inrushes from coal seam roofs while also protecting groundwater resources. However, accurately identifying the migration paths of grouts remains a bottleneck for the further application of grouting modification technology to fractured rock masses. Methods This study investigated a coal mine threatened by both water inrushes from the coal seam roof and a short supply of water resources within the Jurassic coalfield in the middle reaches of the Yellow River basin, focusing on the …
An Automated Attitude Control Method For The Rotary Steerable System And Its Validation Through Hardware-In-The-Loop Simulation, Zhang Nan, Ren Bai’An, Li Fei, Liu Ziqi, Lyu Fangxing
An Automated Attitude Control Method For The Rotary Steerable System And Its Validation Through Hardware-In-The-Loop Simulation, Zhang Nan, Ren Bai’An, Li Fei, Liu Ziqi, Lyu Fangxing
Coal Geology & Exploration
Objective The traditional manual control mode of a rotary steerable system (RSS) faces challenges, including response delay and low control efficiency. To address these challenges, this study proposed a closed-loop automated attitude control method for the RSS and verified its effectiveness through hardware-in-loop (HIL) simulation. Methods This study focuses on the drilling process of a point-the-bit RSS. In the case of deviations between measured and target attitudes, the control parameters were calculated based on the deviation signals using a closed-loop controller, driving the RSS actuator to conduct trajectory correction. Afterward, the actual attitude was yielded and then entered the input …
Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin
Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin
Coal Geology & Exploration
Objective The pore structures of clastics play a crucial role in assessing the potential of saline aquifers for geologic CO2 sequestration. Current studies on pore structures during CO2 sequestration focus primarily on artificial cores. However, compared to artificial cores, natural cores feature more complex pore size distributions and stronger heterogeneity. Methods This study examined a natural core from deep reservoirs in the Ordos Basin and two artificial cores with different porosities through CO2-water displacement experiments under water-saturated conditions. Using a nuclear magnetic resonance (NMR) analysis and imaging system for multiphase fluid displacement, this study analyzed the …
Impacts Of Anti-Rock Burst Multistage Hydraulic Fracturing Using Horizontal Wells On Mining Roadways And Fracture Control Techniques: A Case Study Of Mining Facein The Zhaoxian Coal Mine, Shaanxi Province, Liu Xiugang, Jiang Zaibing, Yang Juan, Liu Mingjun, Pang Tao, Wu Weixing, Tu Xiaolong, Mo Haitao, Guo Xiaolong, Du Xinfeng
Impacts Of Anti-Rock Burst Multistage Hydraulic Fracturing Using Horizontal Wells On Mining Roadways And Fracture Control Techniques: A Case Study Of Mining Facein The Zhaoxian Coal Mine, Shaanxi Province, Liu Xiugang, Jiang Zaibing, Yang Juan, Liu Mingjun, Pang Tao, Wu Weixing, Tu Xiaolong, Mo Haitao, Guo Xiaolong, Du Xinfeng
Coal Geology & Exploration
Objective Surface multistage hydraulic fracturing of hard roofs using horizontal wells serves as an important technique for rock burst control in mines. However, fracturing technique under improper control might pose adverse impacts on excavated mining roadways underground, causing roadway deformation, mesh failure with block falling, and the flow of fracturing fluids into the roadways. Methods This study investigated certain mining face of the Zhaoxian Coal Mine in the Yonglong mining area, Shaanxi Province. Targeting different characteristics and phenomena of roadways following hydraulic fracturing, this study analyzed the reasons why fracturing fluids flowed into roadways during hydraulic fracturing using theoretical analysis, …
Lithofacies Paleogeography Of The Ordovician Kelimoli-Lashizhong Formations Along The Western Margin Of The Ordos Basin, Wang Weibin, Ma Zhanrong, Hu Aiping, Zhang Qian, Li Wenhou, Chen Qiang, Ma Yao, Wang Yanbo
Lithofacies Paleogeography Of The Ordovician Kelimoli-Lashizhong Formations Along The Western Margin Of The Ordos Basin, Wang Weibin, Ma Zhanrong, Hu Aiping, Zhang Qian, Li Wenhou, Chen Qiang, Ma Yao, Wang Yanbo
Coal Geology & Exploration
Objective The period during the deposition of the Middle-Late Ordovician Kelimoli-Lashizhong formations witnessed a key transition of the tectonic framework along the western margin of the Ordos Basin. Investigating the lithofacies paleogeography of these formations can reveal the tectono-sedimentary responses during this period, thereby providing a basis for the resource potential prediction, exploration, and exploitation of natural gas in the study area. Methods Using field section observations, core observations, and log interpretations, as well as previous research results, this study comprehensively analyzed the Middle-Late Ordovician strata in the Ordos Basin from the perspectives of stratigraphy, sedimentary system division, and sedimentary …
Intelligent Lithology Identification While Drilling Using Bilstm Integrating Attention Mechanism, Wang Xi, Peng Fengjia, Li Siyang, Guo Xiao, Zhang Feifei, Ran Xiaofeng, Zhang Cong
Intelligent Lithology Identification While Drilling Using Bilstm Integrating Attention Mechanism, Wang Xi, Peng Fengjia, Li Siyang, Guo Xiao, Zhang Feifei, Ran Xiaofeng, Zhang Cong
Coal Geology & Exploration
Objective Vibration signals while drilling reflect the physical properties and microstructural characteristics of rocks, providing a valuable basis for real-time lithology identification. However, existing models suffer from limited accuracy and robustness due to the low dimensionality of signal features and the class imbalance induced by variations in the rock layer thickness. Methods To overcome these limitations, this study proposed a novel lithology identification method based on a bidirectional long short-term memory (BiLSTM) network that integrates attention mechanism (also referred to as the BiLSTM-Attention). This approach incorporates automated feature extraction and class weight adjustment strategies to enhance both the classification performance …
Solving Data Mining Challenges In Neutrosophic Environments Using Bio-Inspired Optimization Techniques, Samia Mandour, Abduallah Gamal, Mohamed Belal
Solving Data Mining Challenges In Neutrosophic Environments Using Bio-Inspired Optimization Techniques, Samia Mandour, Abduallah Gamal, Mohamed Belal
Neutrosophic Sets and Systems
No abstract provided.
Uniqueness And Prospects Of Co2 Sequestration In Basalts, Hu Chenlin, Sang Shuxun, Li Xin, Rui Zhenhua, Liu Shiqi, Wang Ziqiang, Xie An, Yu Huan
Uniqueness And Prospects Of Co2 Sequestration In Basalts, Hu Chenlin, Sang Shuxun, Li Xin, Rui Zhenhua, Liu Shiqi, Wang Ziqiang, Xie An, Yu Huan
Coal Geology & Exploration
Objective and Method CO2 sequestration in basalts offers advantages such as permanent carbonation and elevated safety. Based on literature review and case studies, this study compared the CO2 sequestration performance of basalts, clastic rocks, and carbonate rocks. Accordingly, the pros and cons of technologies for CO2 sequestration in these rocks were determined, and the dominant mechanisms underlying the CO2 sequestration were identified. By revealing the characteristics of CO2 sequestration in the three rock types based on representative projects and tests, this study conducted a comparative analysis of the mechanisms, conditions, technologies, potential, and siting for …
New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş
New Bis-Piperazine Derivatives: Synthesis, Characterization (Ir, Nmr), Gamma-Ray Absorption, Antimicrobial Activity, Molecular Docking And Dynamics Study, Yasemi̇n Ünver, Arzu Coşkun, Fati̇h Çeli̇k, Hali̇l İbrahi̇m Güler, Kadri̇ye İnan Bektaş
Turkish Journal of Chemistry
A series of novel bis-piperazine derivatives (2a–2f) were synthesized and structurally characterized via Fourier transform-infrared and nuclear magnetic resonance spectroscopic techniques. Their gamma-ray shielding efficiencies were investigated through simulations on the Monte Carlo-based Geant4-GATE platform, and the results were benchmarked against data obtained from the XCOM and Phy-X software. A simulation model incorporating an NaI scintillation detector and a point gamma source was developed. Key shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and mean free path (MFP), were evaluated at gamma energies of 80, 120, 662, 1173, and 1332 keV. Additionally, the energy absorption buildup factor …