Physical Sciences and Mathematics Commons^™

Reasons Of Low Yield And Stimulation Measures For Cbm Wells In Junlian Area, Li Ying, Zheng Rui, Luo Kai, Zhu Yanming, Zhang Yimin

Coal Geology & Exploration

Coalbed methane fields in Junlian area have good development potential, but the existence of a large number of low-production and low-efficiency wells has restricted the increase of productivity. This paper analyzes the coupling relationship between high-productivity wells and geological factors from the perspective of geological engineering integration, analyzes the causes of inefficient wells from three aspects of geology, drainage and engineering, and evaluates the corresponding reform measures. The results show that the formation of inefficient wells in the north and the west of the study area is mainly affected by gas-bearing properties, fault distribution, production horizons, production and drainage rhythms, …

Corrosion And Degradation Of Feldspar Sandstone In Acidic Environment, Zhou Bin, Zhang Dongming, Xu Jiang, Cheng Liang, Li Jiaxin

Coal Geology & Exploration

In order to study the effect of acidic environment on the corrosion and deterioration of rocks, CT images processing technology was used to analyze the meso-composition and structural changes of feldspar sandstone after soaking in acidic water. Shimadzu AGI-250 servo material testing machine was used to carry out uniaxial compression test to observe the deterioration of mechanical parameters. The results show that the total density of the feldspar sandstone decreased Ofter the acidic environment treatment, the distribution trend is homogeneous, and the mineral with higher density is formed in the local area. The secondary pores of the feldspar sandstone increased …

Development Characteristics Of Freezing Temperature Field Of Coastal Soft Soil Strata, Chen Junhao, Zhuang Yan, Chen Bijian, Zhao Zhenwei, Wang Qiyun

Coal Geology & Exploration

In order to research the temperature fields and development law of freezing in the construction of connected aisle in coastal soft soil stratum, based on connected aisle between Luoxiu road station and Baise road station of Shanghai subway Line 15, the thickness and average temperature of frozen curtain, and the freezing process were analyzed. The temperature fields and development law of freezing were predicted by the three-dimensional numerical model of the connected aisle and the temperature data which were analyzed. The results show that the inherent pressure in soft soil causes initial pressure in the pressure relief hole. A lot …

Overburden Failure Simulation Under Double Coal Seams Mining In A Coal Mine In North Shaanxi Province, Sun Xueyang, Zhang Qi, Li Cheng, Zhang Lei

Coal Geology & Exploration

Under the conditions of multi-seam mining, the overburden failure of coal seams has unique characteristics, which affects the mine production arrangement. Taking a mine in northern Shaanxi Province as an example, based on the geological and mining conditions of the mine, the influence of double-seam mining on overburden rock damage was analyzed by using the method of similar material simulation experiment and numerical simulation. The results show that the height of the caving zone and the height of the fractured zone in the overburden of coal seam obtained by using similar material simulation and numerical simulation with different widths of …

Collapse Column Identification Method Based On Seismic Waveform Indication Inversion And Its Application, Wan Zhaofei, Guo Zenghu, Wang Peng, Tang Meizhen, Han Tianbao, Liu Liangqiong

Coal Geology & Exploration

During the CBM exploration and development, the collapse column is one of the important factors restricting the exploration effectiveness of coalbed methane. Therefore, the effective identification of collapse column is of great significance for the improvement of CBM exploration. The previous identification methods are based on the discontinuity of the in-phase axis of seismic reflection caused by collapse column. In this paper, the collapse column is innovatively regarded as a kind of geological anomaly, and the identification and prediction of the collapse column are attempted by means of waveform indication inversion. Firstly, through the analysis of logging data and geological …

The High-Resolution Transient Electromagnetic Detection Technology For Ultra-Shallow Layer In Coal Mine, Zhang Jun

Coal Geology & Exploration

In order to reduce the blind zone of the transient electromagnetic detection in mines and improve the detection accuracy, the high-resolution transient electromagnetic detection technology for the ultra shallow layer in mines is studied. The high-resolution transient electromagnetic detection technology for ultra-shallow layer in mines is not only suitable for conventional mine geological exploration, but also for high-resolution detection of shallow geological bodies such as cracks in the roof of the mine roadway, ensuring the safe and efficient mining. Through theoretical research, the feasibility of the shallow high-resolution transient electromagnetic method in mine was established; the hardware system of the …

Experimental Study On The Frequency Dispersion Response Of Composite Electrical Properties Of Coal, Meng Hui, Li Jian, Lei Dongji, Wang Yajuan

Coal Geology & Exploration

In order to study the characteristics of frequency dispersion response of the composite electrical properties of coal, the real part R and imaginary part X of the composite resistance of coal body at different direction in different measured areas were measured, the frequency dispersion characteristics were analyzed, different classical models were used to conduct data inversion and comparison. The results show that the composite electrical property parameters(absolute value of R and X) of coal are inversely proportional to the measured area, the characteristic frequency points are not offset, the X-frequency divergence decreases with the increase of measurement area; …

Research Status And Prospect Of Drill Pipe Thread Used In Coal Mine, Tian Dongzhuang, Chen Yanyu, Li Qing, Dong Mengmeng, Mou Peiying

Coal Geology & Exploration

Drill pipe is one of the main device for drilling construction of gas drainage, water detection and drainage and geological exploration. Due to complicated force conditions and using environment of drill pipe, accidents in boreholes caused by the failure of drill pipe threads are common. According to different structural classification, the characteristics of drill pipe thread structure in coal mines are introduced in detail; the current research status of thread stress distribution and failure analysis of thread are summarized. The research methods of thread stress distribution mainly include analytical method, finite element method and test method. The main causes of …

Design Of Piezoelectric Effect-Based Energy Recovery Device Wile Drilling, Wu Tianyu, Zheng Jun, Zhang Bo, Chen Yu, Tian Hong, Dou Bin

Coal Geology & Exploration

Aiming at the problem of continuous power supply of downhole instruments and the recovery of longitudinal vibration energy of drill pipe in drilling field, a new type of energy recovery device based on positive piezoelectric effect was designed. The radial dimension parameters and piezoelectric materials were designed by field experiences and geological survey reports. The piezoelectric coupling model was established based on the numerical simulation software COMSOL Multiphysics, and the length range and the best installation position of the piezoelectric plate were obtained through forced vibration analysis. Through modal analysis and frequency response research, it is obtained that the natural …

Unidirectional Na+ Influx Under Different Growth Stages Of Puccinellia Tenuiflora And Wheat, C. M. Wang, J. L. Zhang, G. Q. Wu, Suomin Wang

IGC Proceedings (1993-2023)

No abstract provided.

Isolation And Characteristics Of Hydrogen-Oxidizing Bacteria In The Leguminous Rhizosphere In Grassland Of Sanjiangyuan Region, Weiwei Wang, Bo Fu, Changhui Li

IGC Proceedings (1993-2023)

No abstract provided.

Carbon And Nitrogen Characteristic In Plants And Soils Of The Degraded Alpine Kobresia Pygmaea Meadow In The Tibetan Plateau, Qiji Wang, Shixiong Li, Zenchun Jing, Wenying Wang

IGC Proceedings (1993-2023)

No abstract provided.

Nitrogen, Phosphorus And Potassium Utilization And Their Nutrient Cycling In A Beef‐Forage Production System, Yusuke Tabata, Masayuki Kitagawa, Kazato Oishi, Hajime Kumagai, Shinichi Kume, Hiroyuki Hirooka

IGC Proceedings (1993-2023)

No abstract provided.

Yield-Stress Fluids In Confined Geometries, Thalia Magyar

Electronic Thesis and Dissertation Repository

A yield-stress fluid is a material that has properties of both solids and conventional liquids that only begins to flow when subject to a finite stress. The behaviour of yield-stress fluids is interesting and important in many applications. It is expected that the rheological properties of a yield-stress fluid will change when confined to a region with a length scale comparable to the characteristic scale of its microstructure. The particle size and polydispersity of two yield-stress fluids, Carbopol and poly(N-isopropylacrylamide), were determined using dynamic light scattering. A rheological characterization was performed on these two yield-stress fluids. Flow of …

Framework For Kernel Based Bm3d Algorithm, Mena Abdelrahman Massoud

Electronic Thesis and Dissertation Repository

Patch-based approaches such as Block Matching and 3D collaborative Filtering (BM3D) algorithm represent the current state-of-the-art in image denoising. However, BM3D still suffers from degradation in performance in smooth areas as well as loss of image details, specifically in the presence of high noise levels.

Integrating shape adaptive methods with BM3D improves the denoising outcome including the visual quality of the denoised image; and also maintains image details. In this study, we proposed a framework that produces multiple images using various shapes. These images were aggregated at the pixel or patch levels for both stages in BM3D, and when appropriately …

Computational Methods For Predicting Protein-Protein Interactions And Binding Sites, Yiwei Li

Electronic Thesis and Dissertation Repository

Proteins are essential to organisms and participate in virtually every process within cells. Quite often, they keep the cells functioning by interacting with other proteins. This process is called protein-protein interaction (PPI). The bonding amino acid residues during the process of protein-protein interactions are called PPI binding sites. Identifying PPIs and PPI binding sites are fundamental problems in system biology.

Experimental methods for solving these two problems are slow and expensive. Therefore, great efforts are being made towards increasing the performance of computational methods.

We present DELPHI, a deep learning based program for PPI site prediction and SPRINT, an algorithmic …

Mathematical Modelling Of Prophage Dynamics, Tyler Pattenden

Electronic Thesis and Dissertation Repository

We use mathematical models to study prophages, viral genetic sequences carried by bacterial genomes. In this work, we first examine the role that plasmid prophage play in the survival of de novo beneficial mutations for the associated temperate bacteriophage. Through the use of a life-history model, we determine that mutations first occurring in a plasmid prophage are far more likely to survive drift than those first occurring in a free phage. We then analyse the equilibria and stability of a system of ordinary differential equations that describe temperate phage-host dynamics. We elucidate conditions on dimensionless parameters to determine a parameter …

Stable Carbon And Oxygen Isotope Investigation Of Pleistocene Growing-Season Paleoclimate Using Tree-Ring Cellulose From The Missinaibi Formation, Adam Creek, James Bay Lowland, Canada, Jumin Lee

Electronic Thesis and Dissertation Repository

The isotopic compositions of cellulose in tree rings provide a record of seasonal and annual climatic conditions such as precipitation and temperature. We analyzed stable isotopes of carbon (δ¹³C_cellulose) and oxygen (δ¹⁸O_cellulose) in early-wood and late-wood of five conifer sub-fossil wood samples from the Missinaibi Formation, which likely grew during the peak of Marine Isotope Substage (MIS) 5a (~82 kya) at Adam Creek, Ontario. There was no systematic difference between early-wood and late-wood for either δ¹³C_cellulose or δ¹⁸O_cellulose, suggesting similar climatic conditions throughout …

An Effective Method For Synthesizing The Abbreviated Disjunctive Normal Form Of A Boolean Function, Erkin Urunbaev

Scientific Journal of Samarkand University

In discrete mathematics, minimizing Boolean functions in the class of disjunctive normal forms is one of the necessary tasks. This paper presents an effective method for synthesizing the reduced disjunctive normal form of a Boolean function.

Uniqueness Of Solution The Problem Of Integral Geometry Of Volterra Type With A Weight Function Of A Special Type, Zarifjon Ochilov

Scientific Journal of Samarkand University

A new class of Volterra type integral geometry problems with a special-weight function is considered. Theorem of uniqueness of a solution are proved, stability estimates and the inversion formula in Sobolev spaces are obtained, thereby showing the weak incorrectness of the solution of the integral geometry problem

Misogyny Detection In Social Media On The Twitter Platform, Elena Shushkevich

Doctoral

The thesis is devoted to the problem of misogyny detection in social media. In the work we analyse the difference between all offensive language and misogyny language in social media, and review the best existing approaches to detect offensive and misogynistic language, which are based on classical machine learning and neural networks. We also review recent shared tasks aimed to detect misogyny in social media, several of which we have participated in. We propose an approach to the detection and classification of misogyny in texts, based on the construction of an ensemble of models of classical machine learning: Logistic Regression, …

Emplacement Conditions Of Magma(S) Forming Jurassic Plutonic Rocks In Gümüşhane (Eastern Pontides, Turkey), Emre Aydinçakir, Ramazan Gündüz, Cem Yücel

Bulletin of the Mineral Research and Exploration

In this study, the petrography, mineral chemistry and crystallization conditions were reported for the Alemdar and Işıkdere plutons located in limited areas in the south of the Eastern Pontides. These plutons, which trend mostly in NE-SW directions, were emplaced by cutting the Early- Middle Carboniferous-aged Gümüşhane Granitoid and Early-Middle Jurassic Şenköy formation. Petrographically, the studied plutons are compositionally fine to medium grained quartz-diorite, quartz monzodiorite and tonalite. The rocks in the plutons have granular, poikilitic, monzonitic, graphic and rare porphyritic textures with consist of plagioclase, (An05-92), hornblende (Mg# = 0.52- 0.81), biotite (Mg# = 0.32-0.67), orthoclase, quartz and Fe-Ti oxide. …

Gw190412: Observation Of A Binary-Black-Hole Coalescence With Asymmetric Masses, R. Abbott, T. D. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We report the observation of gravitational waves from a binary-black-hole coalescence during the first two weeks of LIGO's and Virgo's third observing run. The signal was recorded on April 12, 2019 at 05:30:44 UTC with a network signal-to-noise ratio of 19. The binary is different from observations during the first two observing runs most notably due to its asymmetric masses: a ∼30 M_ʘ black hole merged with a ∼8 M_ʘ black hole companion. The more massive black hole rotated with a dimensionless spin magnitude between 0.22 and 0.60 (90% probability). Asymmetric systems are predicted to emit gravitational waves …

Odu Researchers Lead Team That Secured Department Of Defense Offshore Wind Grant, News @ Odu

News Items

No abstract provided.

Deciphering Tip-Enhanced Raman Imaging Of Carbon Nanotubes With Deep Learning Neural Networks., Usant Kajendirarajah, María Olivia Avilés, François Lagugné-Labarthet

Chemistry Publications

Recent release of open-source machine learning libraries presents opportunities to unify machine learning with nanoscale research, thus improving effectiveness of research methods and characterization protocols. This paper outlines and demonstrates the effectiveness of such a synergy with artificial neural networks to provide for an accelerated and enhanced characterization of individual carbon nanotubes deposited over a surface. Our algorithms provide a rapid diagnosis and analysis of tip-enhanced Raman spectroscopy mappings and the results show an improved spectral assignment of spectral features and spatial contrast of the collected images. Using several examples, we demonstrate the robustness and versatility of our deep learning …

Modeling Anatomic Changes For Adaptive Radiotherapy In Locally Advanced Lung Cancer Patient Population, James Alexander Kavanaugh

LSU Doctoral Dissertations

Anatomic changes occurring mid-treatment for patients undergoing radiation therapy for locally advanced lung cancer can degrade the quality of the intended treatment plan. These changes include tumor regression, geometric misalignment, and lung density changes (atelectasis and pleural effusion), and are visible on the daily 3D cone beam CT (CBCT). To maintain the intended treatment quality, adaptive radiotherapy (ART) can be employed to modify the treatment plan to account for these anatomic changes. However, the evaluation on when to adapt is currently completed manually by the treating clinicians, resulting in a subjective and inconsistent application. To address these limitations, a series …

Nitrogen Losses Through Denitrification From A Grazed Pasture As Affected By The Use Of Anitrification Inhibitor, W. Sun, Jiafa Luo, S. Lindsey, Sterwart F. Ledgard

IGC Proceedings (1993-2023)

No abstract provided.

Plant Species Composition And Soil Microbial Community Structure In A Semi‐Natural Grassland In Japan, Shu‐Ichi Sugiyama, Atushi Okubo, M. Zabed Hossain, Guangcheng Liu

IGC Proceedings (1993-2023)

No abstract provided.

Changes In Inorganic Ion Accumulation And Growth Of Leymus Chinensis Community Along The Retrogression On The Songnen Grassland In Northeastern China, Lianxuan Shi, Jixun Guo

IGC Proceedings (1993-2023)

No abstract provided.

Long‐Term Phosphorus Fertilization And Perennial Legumes Addition Impacts On A Temperate Natural Grassland: Ii. Total And Particulate Soil Organic Carbon, Lucía Salvo, José A. Terra, Walter Ayala, Raül Bermudez, José Correa, Paola Avila, Jorge Hernández

IGC Proceedings (1993-2023)

No abstract provided.