Sealing Performance Evaluation Criteria And Profile Optimization Of The Volumetric Cavities Of Positive Displacement Motors For Directional Drilling,
2026
School of Mechanical Engineering, Southwest Petroleum University, Chengdu 610500, China
Sealing Performance Evaluation Criteria And Profile Optimization Of The Volumetric Cavities Of Positive Displacement Motors For Directional Drilling, Kuang Yuchun, Hu Xin, Zhou Jingpei, Luo Jinwu, Liu Yihui, Han Yiwei
Coal Geology & Exploration
Objective Constrained by complex stratigraphic conditions in underground coal mines, directional drilling faces challenges such as low efficiency when encountering medium-hard and hard formations. Positive displacement motors (PDMs) with a diameter of 89 mm are commonly used for directional drilling. Their efficiency is primarily influenced by the sealing performance of their volumetric cavities, which further significantly affects the drilling efficiency. Methods Based on the structural characteristics of the three-dimensional (3D) volumetric cavities of PDMs and the simulation method of two-way fluid-structure interactions, this study proposed the criteria for quantitatively evaluating the efficiency and volumetric cavity performance of PDMs, followed by …
Table Of Contents,
2026
China Coal Technology and Engineering Group (CCTEG)
Instruments For Simulation Experiments On Coal-Rock Dynamic Disasters In China: Current Status And Key Challenges,
2026
State Key Laboratory for Safe Mining of Deep Coal Resources and Environment Protection, Anhui University of Science & Technology, Huainan 232001, China
Instruments For Simulation Experiments On Coal-Rock Dynamic Disasters In China: Current Status And Key Challenges, Yuan Liang, Tang Haopeng, Ma Yankun, Wu Hua, Zhang Yachao, Jiao Biao, Wang Hao
Coal Geology & Exploration
Background Coal-rock dynamic disasters represent engineering disasters caused by the instability of the multi-phase and multi-field coupling of coal strata under mining disturbances, severely restricting the safe exploitation of deep coal resources. Elucidating the disaster-inducing mechanisms lays the foundation for exploring effective monitoring and early warning, along with prevention and control technologies, while instruments for simulation experiments provide crucial tools for investigating the mechanisms. Gradually increasing scientific and technological level has contributed to the continuous improvement in China's independently developed instruments for simulation experiments on coal-rock dynamic disasters. However, as engineering activities progressively extend toward deep parts, the multi-phase and …
Biogeochemical Mechanisms Behind Water Quality Evolution And Valuable Element Reutilization Of Abandoned Mine Drainage: A Review,
2026
Key Laboratory of Karst Georesources and Environment, Ministry of Education, Guizhou University, Guiyang 550025, China; College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025, China
Biogeochemical Mechanisms Behind Water Quality Evolution And Valuable Element Reutilization Of Abandoned Mine Drainage: A Review, Wu Pan, Huang Jiangxun, Li Qingguang, Zhang Ruixue, Li Bo
Coal Geology & Exploration
Background Abandoned mine drainage, also known as acidic mine drainage (AMD), represents a major pollution source in mining areas while also serving as an important carrier of strategic critical metals and underground space utilization. In China, water pollution stemming from coal mining is more severe in the south than in the north. This spatial pattern is jointly shaped by climatic conditions, geological settings, and mining history. Advances From the perspective of the environmental geochemical frontier, this study presents a systematic review of AMD formation and evolution mechanisms, as well as technologies for water pollution prevention and control, resource recovery, and …
Pathways And Modes For Prevention And Control Of Acid Mine Drainage-Induced Pollution In China,
2026
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu 610059, China; Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, Ministry of Ecology and Environment, Chengdu 610059, China; College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, China
Pathways And Modes For Prevention And Control Of Acid Mine Drainage-Induced Pollution In China, Liu Guo, Chen Qian, Gan Xinzhu, Tang Jie, Zhu Mingtan, Fan Jiajun, Ren Shuang
Coal Geology & Exploration
Background Mining activities in polymetallic sulfide mines significantly disrupt regional hydrogeochemical equilibrium, leading to the formation of acid mine drainage (AMD). Consequently, severe pollution of aquatic environments occurs, posing a threat to regional water resource security. To lay the foundation for the prevention and control of AMD-induced pollution, it is necessary to investigate the formation and evolution mechanisms of AMD and establish a low-cost, sustainable risk management and control mode. Methods Based on field sampling and literature research, this study made statistics of the hydrochemical characteristics of AMD from different polymetallic sulfide mining areas across China and elucidated the processes …
Geophysical Responses And Their Statistical Relationships With Lithium And Kaolinite Contents For Lithium-Rich Coals In The Yangquan Mining Area,
2026
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China
Geophysical Responses And Their Statistical Relationships With Lithium And Kaolinite Contents For Lithium-Rich Coals In The Yangquan Mining Area, Chen Tongjun, Xu Haicheng, Li Wan
Coal Geology & Exploration
Objective China, representing the world's largest consumer of lithium resources, suffers from a limited endowment of conventional lithium resources, rendering it inevitable for China to seek to develop and utilize abundant coal-hosted lithium resources. Through a comparative analysis of coal samples from the lithium-rich No. 8 and the ordinary No. 15 coal seams in the Taiyuan Formation, Yangquan mining area, Shanxi Province, this study explored the statistical relationships between the lithium and kaolinite contents and geophysical responses. Accordingly, the feasibility of the indirect detection of coal-hosted lithium resources using geophysical methods was assessed. Methods First, by testing the lithium content …
Underground Tunnel Drilling Technology And Equipment For Coal Mines In China: A 50-Year Retrospective And Prospects,
2026
CCTEG China Coal Research Institute, Beijing 100013, China; CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
Underground Tunnel Drilling Technology And Equipment For Coal Mines In China: A 50-Year Retrospective And Prospects, Tian Hongliang, Li Wangnian, Li Quanxin, Yao Ke, Liu Jianlin, Chang Jianghua
Coal Geology & Exploration
Bcakground Underground tunnel drilling in coal mines represents an indispensable key means for the safe and efficient coal mining, precise disaster prevention and control, and geological transparency of coal mines. This study presents a systematic review of the development history of underground tunnel drilling technology and equipment for coal mines in China over the past 50 years, during which the technology and equipment have evolved from technology introduction to independent innovation and from following to keeping pace with and even to overtaking international counterparts.Advances Initially, this study expatiates on both the important position of coal resources in the national …
Key Techniques And Application Of The Zdy15000ldk High-Power Automatic Directional Drilling Rig,
2026
CCTEG China Coal Research Institute, Beijing 100013, China; CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China
Key Techniques And Application Of The Zdy15000ldk High-Power Automatic Directional Drilling Rig, Li Quanxin, Zhang Gang, Fang Peng, Xing Wang, Yao Ke, Zhang Rui, Zhang Boyang, Zhao Xuefeng, Shi Yang, Sun Hanyu, Jia Qian
Coal Geology & Exploration
Objective For deep mining of coal mines, conventional directional drilling rigs face challenges including high labor intensity, limited control accuracy, a low intelligence level, and failure to meet the demand for efficient gas drainage. Meanwhile, high-power automatic drilling rigs encounter technical bottlenecks in automation, control accuracy, and process intelligence in this context. To address these issues, this study proposed an integrated and systematic solution—the ZDY15000LDK high-power automatic directional drilling rig. Methods Using a compact structural layout, a drill rod handling system was developed, consisting of a drill rod loading/unloading manipulator with four degrees of freedom and an automatic drill rod …
Stoker-Fired Laboratory Boiler As A Tool For Optimising The Solid Fuel Combustion Process,
2026
Department of Solid Fuels Quality Assessment, Central Mining Institute – National Research Institute (Katowice, Poland)
Stoker-Fired Laboratory Boiler As A Tool For Optimising The Solid Fuel Combustion Process, Przemysław Rompalski, Justyna Guzy-Proc, Mariusz Kieczek
Journal of Sustainable Mining
This paper presents the results of quality testing performed on a stoker-fired laboratory boiler to present the technical potential of the boiler as a tool for optimising the combustion process of prepared solid fuels (granulate, energy blend) in the context of current demands related to the decarbonisation policy. The comprehensive testing of such fuels at a laboratory scale makes it possible to gain deep insights into the quality parameters of the fuel, flue gas and combustion waste, as well as to determine the combustion process parameters before the fuel is introduced for combustion in broader power engineering and household boilers. …
Productive Armature,
2026
Rhode Island School of Design
Productive Armature, Gabriel Ofem Peter
Masters Theses
What if water was all you had, what if your only source of survival was a body of water? I shudder to think that some people get to be put in this situation in the world we live in. As I understand the importance of water to survival, it is obvious that water can be the only lifeline of survival for a community. This is the experience for residents of Makoko, Lagos. Their survival depends on the Lagos Lagoon, a large body of water flowing in from the Atlantic Ocean. This research looks beyond the surface of what this community …
Innovation Strategies For Small And Medium-Sized Construction Companies In Nigeria,
2026
Walden University
Innovation Strategies For Small And Medium-Sized Construction Companies In Nigeria, Olabode Akinkunmi Akindele
Walden Dissertations and Doctoral Studies
No abstract provided.
Ecological Interest Theory Of “Lucid Waters And Lush Mountains Are Invaluable Assets” And Its Application In The Yellow River Basin,
2026
State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China
Ecological Interest Theory Of “Lucid Waters And Lush Mountains Are Invaluable Assets” And Its Application In The Yellow River Basin, Guangqian Wang, Deyu Zhong
Bulletin of Chinese Academy of Sciences (Chinese Version)
To address the core challenges of quantifying ecological value and converting it into economic gains, this study proposes a theoretical framework of ecological interest (EI) based on the principle that “lucid waters and lush mountains are invaluable assets”. Three fundamental origins of ecological interest are explained, including the temporal value discount, the spatial ecological compensation, and the civilizational occupation-compensation balance. These three dimensions establish the logical connection between ecological and economic values. Setting a 5% annual simple interest rate as the benchmark and adopting “Lucid Waters and Lush Mountains” green certificates as the standardized ecological assets for property rights delineation …
An Analytical Framework For Quantifying Urban And Community Resilience To Natural Hazards From Cell-Phone Gps-Location And Traffic-Flow Data,
2026
Southern Methodist University
An Analytical Framework For Quantifying Urban And Community Resilience To Natural Hazards From Cell-Phone Gps-Location And Traffic-Flow Data, Georgios Chatzikyriakidis
Civil and Environmental Engineering Theses and Dissertations
Urban areas are increasingly exposed to natural hazards while accommodating a growing share of the global population, yet a consistent science-based framework for quantifying urban and community resilience remains lacking. This dissertation develops a physics-based analytical framework grounded in statistical mechanics and the quantitative theory of Brownian motion. A city is conceptualized as a complex medium in which citizens move analogously to Brownian particles within a viscoelastic environment, influenced by socioeconomic interactions and infrastructure functionality.
A central premise is that urban resilience, interpreted as engineering resilience (an outcome), can be quantified through a single metric: the mean-square displacement MSD=⟨r²(t)⟩, of …
Saving The Great Basin: Creating Places For The Birds, Bees And Beyond,
2026
University of Nevada, Las Vegas
Saving The Great Basin: Creating Places For The Birds, Bees And Beyond, Carlos Gomez
Hospitality Design Graduate Student Capstones
This project looks at how vacant and underused parcels along the Truckee River in Reno, Nevada, can be rethought as part of a larger ecological system. Rather than treating these parcels as empty leftover spaces, the project sees them as opportunities to create small habitat patches that can support native species, improve stormwater function, and strengthen the river corridor over time. The work focuses on three sites along the Truckee River: California Avenue, Island Avenue, and Commercial Row. Each site responds to a different condition along the urban transect, from a sloped residential river edge to a tighter urban parcel …
The Biowell System: An Integrative Framework That Connects Ecological Sustainability And Mental Wellbeing Through The Regenerative Processes Of Bioswales,
2026
University of Nevada, Las Vegas
The Biowell System: An Integrative Framework That Connects Ecological Sustainability And Mental Wellbeing Through The Regenerative Processes Of Bioswales, Nathan A. Bussa
Hospitality Design Graduate Student Capstones
The Biowell System is an evaluative framework that connects ecological sustainability and mental well-being through the regenerative processes of bioswales.
Shelters In Motion,
2026
University of Nevada, Las Vegas
Shelters In Motion, Erin Nicole Vallido Trasmano
Hospitality Design Graduate Student Capstones
Shelters in Motion is a modular temporary shelter system for festival and outdoor events that replaces disposable tents with reusable, durable design. Overall reducing environmental impact while significantly improving comfort and user experience.
Local And Indigenous Knowledge, Innovation, And Sustainable Development: Creating Sustainable Futures Amidst Crisis Conditions At The Community Level,
2026
Portland State University
Local And Indigenous Knowledge, Innovation, And Sustainable Development: Creating Sustainable Futures Amidst Crisis Conditions At The Community Level, Carlos Andrés Arias
Dissertations and Theses
In 1987, the Brundtland Commission's Our Common Future (1987) made clear the need to reject longstanding development processes and focus on sustainable development. The Commission stressed that actual sustainable development integrates three elements: social development, economic development, and environmental protection. Though developed nations have achieved economic growth through conventional and extractive development practices, these practices have intensified natural disasters driven by climate change, increased food insecurity, and deepened poverty. This has acutely impacted Indigenous and local communities, many of whom face crisis conditions, such as war, terrorism, civil disorder, and their aftermath. Even so, many of these communities successfully implement …
Karstic Cavities Underground Investigation: Gpr And Geotechnical Data Correlation,
2026
Northern Border University, College of Engineering, Civil Engineering Department, Arar, Saudi Arabia
Karstic Cavities Underground Investigation: Gpr And Geotechnical Data Correlation, Mehrez Jamei, Mabrouk Abdelkader, Anwar Ahmed, Yahya Alassaf
Journal of Sustainable Mining
This paper focuses on the methodology involving ground penetration radar (GPR) for detecting and localizing random cavities in underground limestone soil, in conjunction with geotechnical data. A GPR survey was conducted alongside field and laboratory geotechnical tests at a field where mining activities are now promoted (Saudi Arabia Northern Borders Province). The paper presents correlations between the instantaneous amplitude of the reflected electromagnetic (EM) waves and rock quantification distributed (RQD), recovery rock parameter (REC), and uniaxial compressive strength (UCS). The GPR investigation proved to be an efficient nondestructive geophysical method for determining: 1) the …
“The New Normal”: California’S Escalating Wildfire Crisis,
2026
Fordham University
“The New Normal”: California’S Escalating Wildfire Crisis, Alexandra Vasquez
Student Theses 2015-Present
This paper addresses the current state of California's wildfire epidemic and how the increasing effects of climate change have worsened the fires, harming residents' health and the state's economy. The wildfires are shaped by factors such as climate change, land-use choices, and policy designs. California wildfires have worsened substantially in the 21st century, with the worst burns in the 2020 season setting a record of 4.2 to 4.5 million acres destroyed. Given current policies and the administration's disinterest in combating climate change, understanding wildfire history and data is essential to improving California's wildfire resilience, creating sustainable land management practices, and …
The Legacy Of Lead: Lead Exposure's Harmful Effects And Its Concentration In Poc Communities,
2026
Fordham University
The Legacy Of Lead: Lead Exposure's Harmful Effects And Its Concentration In Poc Communities, Layla Sophronia Barber
Student Theses 2015-Present
This thesis examines the disproportionate burden of lead exposure carried by low income, POC communities. The systemic nature of this problem is a symptom of a longstanding legacy of environmental injustice in the United States. Decades of federal neglect are reflected in the higher statistics of lead exposure and poisoning in predominantly black communities. While it is understood that lead exposure poses a serious threat to physical health and early cognitive development, there is a discouraging lack of urgency to remove the toxin from non-wealthy communities. The material covered by this thesis aims to identify and correct the discriminatory social …
