Results 41 to 50 of about 4,519 (226)

Theory and technical system of control of far-near field hard roofs from ground and underground in a large space stope

Meitan xuebao, 2023
The stope space, after mining an extra-thick coal seam with hard roofs, is large, and its law of mining pressure is complex. The mechanism of strong mine pressure action for this stope is unclear, and there is a lack of multi-point control technology ...
Bin YU, Yang TAI, Tiejun KUANG, Rui GAO, Jingxuan YANG, Binwei XIA, Weibing ZHU, Yong LI   +7 more
doaj   +1 more source

System and application of regional fracking of coal seam roof on and under the ground to prevent rockburst

Meitan kexue jishu, 2023
To solve the problems of small local relief range, low continuity and high operational risk of rockburst, regional hydro-fracking and burst prevention system and engineering application research were carried out within thick and hard roof of a coal seam ...
PAN Junfeng, LU Chuang, MA Xiaohui, XIA Yongxue, XIE Fei, XU Gang, DOU Guidong, LYU Dazhao, SUN Xiaodong, MA Wentao   +9 more
doaj   +1 more source

Compliant Pneumatic Feet with Real‐Time Stiffness Adaptation for Humanoid Locomotion

Advanced Robotics Research, EarlyView.
A compliant pneumatic foot with real‐time variable stiffness enables humanoid robots to adapt to changing terrains. Using onboard vision and pressure control, the foot modulates stiffness within each gait cycle, reducing impact forces and improving balance. The design, cast in soft silicone with embedded air chambers and Kevlar wrapping, offers durable,
Irene Frizza, Hiroshi Kaminaga, Philippe Fraisse, Gentiane Venture   +3 more
wiley   +1 more source

Drop‐Location‐Insensitive Droplet‐Based Electricity Generator Using Polydimethylsiloxane Slippery Covalently Attached Liquid Coatings

Advanced Science, EarlyView.
Drop‐location sensitivity remains a key barrier to practical droplet‐based electricity generators (DEGs). Here, a polydimethylsiloxane slippery covalently attached liquid (PDMS‐SCAL)‐coated interface promotes droplet sliding instead of splitting or bouncing, allowing stable electricity generation from randomly falling raindrops. The resulting PDMS‐SCAL‐
Jung Bin Yang, Donghyeon Yoo, Hideaki Teshima, Donghan Lee, Dongwhi Choi, Dong Rip Kim, Nenad Miljkovic   +6 more
wiley   +1 more source

Evolution of roof treatment processes from blasting to hydraulic fracturing to prevent rockburst in thick-hard roof coal mines in Xinjiang, China

Frontiers in Earth Science
Rockburst prevention poses a major challenge in coal mining, with thick and hard roof strata being the primary cause of rockbursts. To analyze the feasibility and effectiveness of using hydraulic fracturing as an alternative to blasting methods for ...
Kunlun Liu, Taotao Du, Taotao Du, Yuhai Wu, Hongping Li, Xu Yang, Jiang Liu, Hongbao Liang, Jianqi Wang   +8 more
doaj   +1 more source

Rock burst mechanism induced by stress anomaly in roof thickness variation zone: a case study

Geomatics, Natural Hazards & Risk, 2022
The variation of hard roof thickness is an essential contributor in triggering rock bursts during longwall mining. Case analysis and numerical modeling were used to study the stress and energy characteristics of the coal and rock mass and its fracture ...
Xianxi Bai, Anye Cao, Wu Cai, Yingyuan Wen, Yaoqi Liu, Songwei Wang, Xuwei Li   +6 more
doaj   +1 more source

MN•CS•IO System: Cross‐Species Study for HBB Function in High‐Altitude Hypoxia Adaptation

Advanced Science, EarlyView.
We developed an integrative mesh‐nanorod sorting, chitosan nanoparticle delivery, and intraosseous injection (MN•CS•IO) system to investigate HBB in high‐altitude hypoxia adaptation. Transplanting Tibetan animals' HBB‐modified Lin‐ cells into mice achieved 95.59% transfection efficiency and 8.15% HBB expression. High‐altitude HBB recipients upregulated
Wenqiao Hui, Lin Mao, Binggang Li, Hanyue Kang, Zhengquan Tang, Sheng Chen, Hui Yang, Yu Qiao, Huiqian Ding, Yuhuan Wang, Min Li, Junjie Hu, Shoudong Ye, Xin Wang, Xiaobin Xu, Yupeng Wang, Tana Wuren, Qian Ban, Baowei Zhang   +18 more
wiley   +1 more source

Dynamic failure and stability model analysis of thick and hard rock with wedge-structure immediate roof occurrence

, 2021
To eliminate roof-control disasters typicallyencountering in mines with thick and hard rock strata, fracturecharacteristics, instability mechanism and prevention methods were investigatedin the study.
Zhao, Tong, Gong, Peilin, Liu, Changyou, Bahramian, Majid, Yetilmezsoy, Kaan   +4 more
core   +1 more source

Exposure to heat waves and drought improves subsequent leaf heat tolerance for five oak species in southern California

American Journal of Botany, EarlyView.
Abstract Premise Given the threats of climate change, we investigated the impact of high temperatures separately and in combination with reduced soil water on leaf heat tolerance for five oaks (Fagaceae) with overlapping ranges in southern California, USA: Quercus agrifolia and Q. chrysolepis (evergreen species), Q. douglasii and Q.
Casey D. Wisely, G. Olivia Plumb, Mira N. Ranganath, Emily Dolida, Ishan Ashford, Graham Luethe, Tim Thibault, Gretchen B. North   +7 more
wiley   +1 more source

Fractural structure of thick hard roof stratum using long beam theory and numerical modeling

, 2017
The thick hard rock (THR) roof of the long-wall mining face is prone to the large-sized cantilever roof, and its sudden fracture will cause serious rock dynamic disasters, such as coal and gas outburst and rockburst. In this study, based on the long beam
Zhao, Tong, Kaan Yetilmezsoy, Changyou Liu, Shuai Zhang, Liu, Changyou, Zhang, Shuai, Zhang, Baisheng, Tong Zhao, Yetilmezsoy, Kaan, Baisheng Zhang   +9 more
core   +1 more source