Engineering Commons^™

Pneumatic Directional Drilling Technology And Equipment For Broken-Soft Coal Seams In Underground Coal Mines, Tian Hongliang, Zhang Jinbao, Wang Li, Fang Jun, Wang Jianqiang

Coal Geology & Exploration

[Objective] The geological conditions of coal seams in China are complex, with a wide distribution of broken-soft coal seams, and a large number of wells have the problems of high gas and coal-gas outburst. Currently, borehole gas drainage is an effective measure for preventing and controlling the gas disasters. [Methods] In response to the problems of uncontrollable drilling trajectory, shallow drilling depth, large blind spots of drainage in conventional rotary drilling process of broken-soft coal seams, as well as multiple stuck drilling accidents, great difficulty in drilling and low drilling efficiency in conventional directional drilling processes, the development history and …

Build-Up Rate Prediction Of Rotary Steerable Tools Based On Delay Differentiation, Li Fei, Zhang Nan

Coal Geology & Exploration

[Objective] Accurate build-up rate prediction of rotary steerable tools is a prerequisite to achieve the precise control of tools. In order to grasp the variation law of the build-up rate of the rotary steerable bottom-hole assembly (RSBHA). [Methods] Based on the structural charaeteristics of the tool, the Euler-Bernoulli beam equation method is used to analyz the forces outing on the composite RSBHA. At the same time, the calculation method of the tool deflection angle in different sections and the bit pre-drilling deflection angle was obtained with consideration to the geometric relationship of the bottom-hole assembly, and the distance between the …

Analysis Of Three-Dimensional Nonlinear Fluid-Solid Coupling Vibration Characteristics Of Coalbed Methane Abandoned Well Plugging String, Xu Zhixin, Wan Jifang, Hong Yi, Liu Hangming, Yi Xianzhong, Diao Binbin, Wang Yanbin

Coal Geology & Exploration

[Objective] The plugging quality of cement plug in abandoned coalbed methane wells is critical to preventing pollutant leakage. Current standards for handling these wells involve simple mud pump injection, which often results in cement plugs with issues like particle agglomeration, bubbles, and micropores. These defects reduce the strength of the cement plug and compromise its sealing performance. [Methods] To address this, vibration technology is applied to the plugging operation, using a specialized tool to induce vibrations in the pipe string. This process enhances the fluidity of the cement slurry via the transmission of vibration energy, thereby improving the plugging quality …

Spatial Distribution And Influencing Factors Of Microseismic Events In Unequal-Length Mining Faces In Coal Mines, Zhou Jinyan, Yang Hongzeng, Gao Jietao

Coal Geology & Exploration

[Objective] The varying length of a mining face along its dip direction or adjusting mining significantly increases water inrush risks of the mining face. This study investigate the hazards and influencing factors brought by unequal length arrangements to the mining face is one of the key issues in deepening the research on coal mine water hazard prevention and ensuring the safe mining face. [Methods] With the No. 15240 mining face, consisting of a narrow part, a wide part, and a slope, in the Jiulong Coal Mine of the Jizhong Energy Fengfeng Group as the engineering background, a large amount of …

Development And Application Of A Supercritical Co2 Pulsed Fracturing-Seepage Coupling Test System, Liu Jiajia, Zhang Yunlong, Nie Zishuo, Gao Zhiyang, Xu Wensong

Coal Geology & Exploration

[Objective] To effectively enhance the extraction effects of coalbed methane (CBM), this study proposed a novel approach for fracturing coals (rocks) using pulsation of supercritical carbon dioxide (CO₂) by combining pulsed fracturing with supercritical CO₂ fracturing. [Methods] A true triaxial test system coupling supercritical CO₂ pulsed fracturing with seepage was independently developed, and its primary structure, characteristics, and functions were elucidated. Then, the supercritical CO₂ pulsed fracturing - seepage/acoustic emission monitoring tests under true triaxial conditions were conducted in the laboratory. The test system, controlling the triaxial stress by combining an independent servo system with …

Link Element Design For A Landing-Gear Mechanism In A Statics And Mechanics Of Materials Course, Amir H. Danesh-Yazdi, Aimee Cloutier, Sean Moseley

Faculty Publications - Mechanical Engineering

In this work, we describe a project involving a link element design for a landing gear mechanism as part of our Statics and Mechanics of Materials I course. During this project, students are asked to design a safe and lightweight linkage that will allow the landing gear to safely and slowly retract from a vertical position to a nearly horizontal one without breaking or stretching more than 10% of its original length. This project is introduced at the halfway point of the 10-week term, at which point students are familiar with the 2D equilibrium of rigid bodies and the concepts …

Remote Sensing Monitoring And Spatiotemporal Characteristics Of Co2 And Ch4 Concentrations In Coal-Electricity Production Bases, Xu Yanfei, Chen Yongchun, Li Jing, Liu Xiaozhou, Miao Wei, Zhao Derong, Rui Chengqi

Coal Geology & Exploration

[Objective] CO₂ and CH₄ are identified as the primary greenhouse gases emitted from energy production in coal-electricity production bases. Mointoring these emissions and analyzing their spatiotemporal distribution are essential components of building a carbon monitoring system in the study area. [Methods] This study investigated Huainan City, Anhui Province as an example to explore the spatiotemporal characteristics of CO₂ and CH₄ in coal-electricity production bases. Specifically, this study examined the CO₂ and CH₄ concentrations in the study area based on data from the GOSAT，OCO-2, and Sentinel-5P satellites，determining the column concentration changes and distribution of CO …

Investigation And Comprehensive Utilization Of Resources In Closed Coal Mines In Anhui Province, China, Liu Feiyue, Chen Wanyun, Yang Ke, Duan Minke, Liu Qinjie, Yang Lingyue

Coal Geology & Exploration

[Objevtive] With the continuously intensive exploitation of coal resources and the structural reform of energy supply, many coal mines in Anhui Province have been closed due to resource depletion or backward production capacity. However, the closed coal mines still host resources such as underground spaces, residual coals, gas, mine water, land, and infrastructure equipment. Hence, reutilizing resources in closed coal mines holds significant engineering value and economic benefits. [Methods] Based on the general information and reutilization status of 59 coal mines in Anhui Province that have been closed since 2013, this study analyzed the distribution characteristics, residual resources, and reutilization …

Physical Simulation Experiments On Mining-Induced Water Inrushes From Coal Seam Floors: Advances In Research And Prospects, Zhang Pingsong, Ou Yuanchao

Coal Geology & Exploration

[Objective] Water inrushes from floors are subjected to the superimposed effects of factors such as specific geological structures, water-rock-stress coupling, and mining disturbance, proving complex, concealed, and abrupt. [Methods] Physical simulation experiments can effectively reproduce the environments of the floors and confined water, intuitively present the whole process of both mining-induced fracture propagation in the floors and the path evolution of water inrushes, and obtain multi-source data of all disaster stages in a real time manner. Therefore, such experiments enjoy unique advantages in investigating water inrushes from floors. [Results and Conclusions] This study reviews the research achievements in water inrushes …

A High-Resolution Method For Processing Coal Measures Seismic Data Based On Anisotropic Medium Theories And Its Application, Li Huiting, Chang Suoliang, Zhang Sheng, Guan Wenyuan, Zhao Xing, Wang Weiqian, Tantai Mingjun, Gao Kaixin

Coal Geology & Exploration

[Objective] The increasing importance of the exploration and exploitation of deep resources poses new requirements for high-precision seismic exploration. Given that conventional isotropy-based data processing methods are no longer applicable to the coal-bearing strata with strong anisotropy. [Methods] This study proposed a method for processing seismic data based on theories of both transverse isotropy medium with a vertical symmetry axis (VTI) media and transverse isotropy with a horizontal axis of symmetry (HTI) media. First, to characterize the depositional characteristics of coal-bearing strata, this study analyzed the features of VTI media, revealing that high-order dynamic correction can effectively eliminate anisotropy-induced event …

Success Factors Analysis In Sorong-Manokwari Railway Infrastructure's Project Evaluation With Fuzzy Ahp Method, Flora Tresia Wehelmina Kambuaya, Ayomi Dita Rarasati

Smart City

An infrastructure project is a long-term project that has two consequences in the form of uncertainty related to risk and expansive costs. Are infrastructure projects a good long-run stimulus to growth economy? Particularly for new developing areas like Papua island where project preparation evaluation has to be established in order to implement the project. Railway infrastructure is a project initiated in 2018 by Indonesia President and is currently still under administration processing. As a new incubator project, the first train project in Papua Land contains several factors that may be essential to drive project success. The critical success factors as …

Analysis Of Traffic Performance And Passenger Car Equivalent Value In Tangerang – Merak Toll Road Section, Jonathan Sidabutar, Sutanto Soehodho, Nahry Nahry

Smart City

Economic growth involves massive movement of logistics, where goods transported by land become the main choice by supplier. One of them being the main access for connecting Java and Sumatera is the Tangerang – Merak toll road. An increase in traffic volume occurs every year, followed by additional problems such as congestion which obviously affects traffic performance. Given this reason, it is necessary to evaluate traffic performance through parameter assessments, which are the degree of saturation and travel speed.

This research was carried out on the Tangerang - Merak toll road section KM 32,300 to KM 35,500 towards Jakarta for …

Optimization Of Motorcycle Emp Values Based On Traffic Flow Dynamics In The Jabodetabek Metropolitan Area, Adi Nugroho

Smart City

The research on optimizing Equivalent Motorized Passenger Car Unit (EMP) values for motorcycles in Jabodetabek addresses the pressing traffic challenges in Indonesia's largest metropolitan area. With rapid population growth and increasing motor vehicles, accurate traffic flow modeling is crucial. Motorcycles, dominant in Jabodetabek's transport, are often misrepresented by EMP values equivalent to cars, leading to inaccurate traffic estimates. Adjusting EMP values, especially in macroscopic modeling, is imperative for precise transportation planning. This study explores the necessity of recalibrating EMP values for motorcycles, crucial for sustainable development and future transportation technology integration. By analyzing traffic dynamics and adjusting EMP values, the …

Evaluation Of Coal Transport Route In Jambi City (Talang Duku Port-East Ring Road Ii), Dwi Angella, Sutanto Soehodho, Nahry Nahry

Smart City

In its implementation, the role of coal transportation infrastructure is important in supporting the mining industry in Jambi City. However, it also causes various complex problems; one of them is traffic congestion on arterial roads in Jambi City. In May 2023, the Jambi Regional Police of the Republic of Indonesia issued a notification letter to stop the mobilization of coal transportation in Jambi Province. The policy caused several coal companies to switch their transportation method to shipping in order to continue operating, while several other companies stopped operating until an indeterminate time. Therefore, this study aims to compare traffic performance …

Analysis Of Cost And Time Efficiency In Container Distribution Between Container Truck And Freight Train From Industrial Area To Port, Indah Imayanti, Sutanto Soehodho, Nahry Yusuf

Smart City

Jakarta International Container Terminal (JICT) in Tanjung Priok Port , which serves export and import containers, can serve up to 5500 TEUs daily. However, no more than 1% of the total containers are transported by freight trains, meaning that 99% of container distribution from industrial areas is carried by trailer trucks. This condition causes a long queue at the container terminal entrance, resulting in delays in the services as well. Currently, Tanjung Priok Port is connected to rail transportation from Cikarang dry port with the frequency of twice a day with 30 flatcars (FC) for each trip. The capacity of …

Impact Of Auxiliary Markings On Intersection Safety, Mhd Tommy Franata, Martha Leni Siregar, Andyka Kusuma

Smart City

The rapid growth of motorcycle vehicles coupled with inadequate traffic discipline contributes to an escalating rate of traffic accidents and casualties. This study investigates the efficacy of auxiliary road markings in enhancing traffic safety and intersection performance along Lieutenant Sutopo Street, Promoter Street, and Boulevard BSD East in South Tangerang, Indonesia. Employing the Traffic Conflict Technique (TCT), the research evaluates safety enhancements and service level alterations subsequent to the installation of road markings. Preliminary observations highlight significant safety concerns and traffic conflicts at the intersection. Consequently, auxiliary road markings are strategically installed to regulate driver behavior, enhance lane discipline, and …

Mobility Index Towards Heritage Tourism Area, Case Study: Borobudur, Prambanan, And Ratu Boko, Kurniawan Pungki Aji, Andyka Kusuma, Efendhi Prih Raharjo

Smart City

Mobility has become a crucial factor in transportation management, especially in the tourism sector. It is a key indicator of the performance of transportation infrastructure and people's response to it. To evaluate mobility in tourist areas, there is a need for tools to represent its value. In this study, the concept of an index as a measure of performance is applied, gathering information into a simpler and more mutually agreeable form. The cultural heritage sites of Borobudur, Prambanan, and Ratu Boko are chosen as an ideal study location due to their popularity internationally. Given the limitations of previous research on …

Disk Engine With Circumferential Swirl Radial Combustor, Brian T. Bohan, Marc D. Polanka, Bennett Staton

AFIT Patents

A disk engine and system configured to provide high power at a reduced axial length is disclosed herein. The disk engine includes a radial compressor, a compressor discharge manifold positioned circumferentially about compressor, a combustion chamber positioned within the discharge manifold and a radial turbine positioned radially inward of the combustion chamber.

Investigating The Feasibility And Mechanisms Of Cold Spray Deposition Of Polymer-Based Powders On Fiber-Reinforced Composite Substrates, Nicholas Beau Mennie

Theses and Dissertations

Fiber-reinforced composites have become important structural components in industries such as aerospace and energy due to their high mechanical strength and relatively light structural weight. However, during operation, these materials can be prone to impact damage and disintegration. Effective protection via metalization and repair of composites would, therefore, reduce the cost and time for replacement parts. Polymer-based cold spray, while a relatively new technique, can be utilized to metalize and possibly repair composite materials subjected to impact-induced damage. In this work, studies involving polymers and composite cold spray were performed to enable the process of safeguarding, enhancing, or repairing various …

Design, Fabrication, And Characterization Of Multifunctional Cellular Structures For Enhanced Impact Energy Mitigation Performance, Kazi Zahir Uddin

Theses and Dissertations

This dissertation investigates the relationship between the structural design of cellular solids and their macroscopic behavior and focuses on the customization of properties through advanced fabrication techniques. The concepts of density gradation and their integration in both non-ordered and ordered cellular structures have been proposed. The investigation focuses on the development of functionally graded foam materials (FGFMs) and mechanical metamaterials to obtain tunable mechanical performance. One significant focus is the fabrication of density-graded foam stacks with various interface adhesives. From the insights gained from the study of interfaces in density-graded foams, certain design and fabrication principles are applied to enhance …

Feasibility Of Eeg Based Detection Of Ischemic Stroke: Studies In A Simple Computational Model, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

Objective: To explore quantitatively, using streamlined mathematics, how transmembrane potential differences across cell bodies of individual cortical neurons could act to produce the skin surface potentials of the electroencephalogram (EEG), and how ischemic stroke might be detected using EEGs in prehospital settings. Methods: From fundamental principles of electrostatics, anatomy, and physiology, one can characterize the strength of apparent dipoles created during activation of the cell bodies of individual cortical neurons. The transient dipole strength in a cortical neuron depends upon the size and surface area of its cell body, its capacitance, and the difference in transmembrane electrical potentials appearing across …

Investigation Of The Use Of Recycled Concrete Aggregates In Porous Asphalt Mixture, Asad Elmagarhe

USF Tampa Graduate Theses and Dissertations

This study aims to address the national need for using recycled concrete in road pavements. This is especially important in the governmental and corporate sectors, where reducing the cost and carbon footprint of construction projects is a priority. The long-term goal is to meet the public demand for environmentally friendly infrastructure and minimize the harmful effects of waste disposal on humans and the environment.

The project focuses on using recycled concrete aggregate (RCA) in porous asphalt pavement to reduce stormwater runoff, a popular environmentally friendly road design. However, compared to regular dense asphalt mixtures, porous asphalt mixtures (PAM) are more …

Learning By Evaluating: An Exploration Of Optimizing Design-Based Instruction, Scott Thorne, Nathan Mentzer, Greg J. Strimel, Scott R. Bartholomew, Jason A. Ware

School of Engineering Technology Faculty Publications

Learning by Evaluating (LbE) is an instructional approach that involves students making comparative judgements of pairs of artifacts, such as student work, portfolios, prototypes, or curated images related to a topic of instruction to enhance critical thinking and decision-making skills. Situated as a primer for learning, the efficacy of LbE stems from actively engaging students in the evaluation process, scaffolding their learning, fostering self-reflection in decision-making, and facilitating the transfer of acquired skills and concepts to academic contexts and project work. However, there is an opportunity to gain deeper insights into classroom integration of LbE and the factors that may …

Synthesis And Characterization Of Vanadium Nitride/Carbon Nanocomposites, Helia Magali Morales, Horacio Vieyra, David A. Sanchez, Elizabeth M. Fletes, Michael Odlyzko, Timothy P. Lodge, Victoria Padilla-Gainza, Mataz Alcoutlabi, Jason Parsons

Mechanical Engineering Faculty Publications

The present work focuses on the synthesis of a vanadium nitride (VN)/carbon nanocomposite material via the thermal decomposition of vanadyl phthalocyanine (VOPC). The morphology and chemical structure of the synthesized compounds were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS). The successful syntheses of the VOPC and non-metalated phthalocyanine (H2PC) precursors were confirmed using FTIR and XRD. The VN particles present a needle-like morphology in the VN synthesized by the sol-gel method. The morphology of the VN/C composite material exhibited small …

Storage And Interaction Diagrams: Extending The Diagrammatic Framework Of Kinetic And Free-Body Diagrams To Other Conservation And Accounting Principles, Amir H. Danesh-Yazdi

Faculty Publications - Mechanical Engineering

After defining a system for analysis, a rigorous process is taught to students in their Statics and Dynamics courses on how to draw proper kinetic, free-body, and impulse-momentum diagrams. While numerous techniques and mnemonics have been mentioned in literature, any experienced instructor can tell a correct free-body diagram apart from an incorrect one. Unfortunately, this is not the case when considering scalar properties such as mass, energy, exergy, and entropy. Different fluid mechanics and thermodynamics texts have treated the diagrammatic representation of these properties either very poorly, or in the case of the latter two, not at all. In this …

Pch-Em: A Solution To Information Loss In The Photon Transfer Method, Aaron J. Hendrickson, David P. Haefner, Stanley H. Chan, Nicholas R. Shade, Eric R. Fossum

Dartmouth Scholarship

Working from a Poisson-Gaussian noise model, a multisample extension of the photon counting histogram expectation-maximization (PCH-EM) algorithm is derived as a general-purpose alternative to the photon transfer (PT) method. This algorithm is derived from the same model, requires the same experimental data, and estimates the same sensor performance parameters as the time-tested PT method, all while obtaining lower uncertainty estimates. It is shown that as read noise becomes large, multiple data samples are necessary to capture enough information about the parameters of a device under test, justifying the need for a multisample extension. An estimation procedure is devised consisting of …

Sliding Mode Control With Chattering Reduction, Suryamshu Ramesh

Doctoral Dissertations and Master's Theses

Sliding Mode Control is a powerful nonlinear control methodology that can handle parametric uncertainties and external disturbances. However, the discontinuous and high-frequency switching nature of the control law introduces the chattering phenomenon, which leads to potential actuator degradation, alterations to the desired response characteristics and, sometimes, instability during control implementation. The main objective of this thesis is to study Sliding Mode Control with chattering reduction. The Sliding Mode Control law involves an equivalent control component and a discontinuous control component. A disturbance estimation is performed based on Lyapunov analysis and adaptive control techniques and then included in the control law …

Study Of Polymer-On-Polymer Cold Spray Deposition Windows Under Apparently Similar Conditions, Ülar Tiitma

Theses and Dissertations

The purpose of this thesis is to explore and expand the capabilities of polymer-on-polymer cold spray demonstrated herein using polyamide 6 (PA6)-based powder and substrates. Experiments were conducted using three different cold spray systems described in this work, permitting more in-depth examination of process response to different cold spray process control parameters, such as nominal system pressure and temperature. Two specific responses of interest were the deposition window (DW) and deposition efficiency (DE) of PA6. The DW was determined by performing several sprays at different calculated particle impact velocities and temperatures. The composite result from these experiments was identification of …

06.24.2024 Orsp Connect, Liz Williamson

ORED Newsletter

Research Networking Lunch (LINC), NIH podcast, CREW (Community First Research Center for Wellbeing and Creative Achievement) Premier Physics Experiment

Economic Planning And Operation Of Ev Charging Infrastructure Participating In Electric Power Markets, Diwas Paudel

USF Tampa Graduate Theses and Dissertations

As electric vehicles (EVs) are becoming more common, there are not enough charging infrastructures to keep up with the projected EV charging demands. This necessitates investment from private enterprises in the charging infrastructure, along with additional government investments, to support the expected EV growth. The profit potential of the EV charging business will be crucial in attracting private enterprises to invest in the infrastructure. The profitability of these infrastructures depends on their location and effective operation. The charging infrastructure needs to be strategically placed and sized in the service area of interest. Once built, they need a robust strategy to …