In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site moni...In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard.展开更多
The height of fractured zone(HFZ) at the high-intensity longwall mining panel plays a vital role in the safety analysis of coal mining under bodies of water. This paper described definitions of the highintensity minin...The height of fractured zone(HFZ) at the high-intensity longwall mining panel plays a vital role in the safety analysis of coal mining under bodies of water. This paper described definitions of the highintensity mining. The processes of overburden failure transfer(OFT) were analyzed, which were divided into the development stage and the termination stage. Through theoretical analysis, the limited suspension-distance and the limited overhanging distance were proposed to judge the damage of each stratum. Mechanical models of strata suspended integrity and overhanging stability were established.A theoretical method to predict the HFZ at the high-intensity longwall mining panel was put forward based on the processes of OFT. Taking a high-intensity longwall mining panel(No. 11915 panel) as an example, the theoretical method proposed, the engineering analogy and the empirical formulas in the Regulation were used to predict the HFZ. The results show that the theoretical result is consistent with the engineering analogies' result and empirical formulas' result. The rationality and reliability of the theoretical method proposed is verified.展开更多
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con...Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.展开更多
High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence ...High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence to analyze mechanisms of HIIT in neuromuscular activation,hormonal responses,muscle fiber adaptation,and metabolic pathway effects.It focuses on its effectiveness in enhancing explosive power,maximum strength,and strength endurance,while also examining the integration of HIIT with traditional resistance training,periodized programming,and personalized prescription.Scientific implementation of HIIT can effectively diversify or even replace conventional strength training,not only offering positive directional changes for strength development but also introducing innovative approaches to sports performance training practices.展开更多
[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of ...[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of Science,SPORTSDiscus,PsycINFO,SCOPUS,CINAHL)up to May 2025.Seventeen randomized controlled trials(RCTs;total n=1142)met inclusion criteria:adults with stroke,device-based HIIT(≥70%HRR/VO 2peak),and outcomes assessing VO_(2)peak,6-min walk distance(6MWD),or Berg Balance Scale(BBS).Methodological quality was evaluated using the PEDro scale.Pooled effect sizes(Hedges'g)were calculated via random-effects models,with heterogeneity quantified by I^(2).[Results]HIIT significantly improved peak oxygen uptake(VO_(2)peak)versus controls(g=0.59,95%CI:0.44-0.75,p<0.001;I^(2)=16.29%).Low heterogeneity and symmetrical funnel plots supported robustness.HIIT also enhanced walking endurance(6MWD:g=0.32,95%CI:0.16-0.48,p<0.01;I^(2)=30%).In contrast,no significant benefit was observed for balance function(BBS:g=0.07,95%CI:-0.13-0.26,p=0.50;I^(2)=0%).[Conclusions]HIIT is a safe and highly effective intervention for enhancing aerobic capacity and walking function post-stroke.Its benefits are maximized at higher intensities and longer durations but do not extend to balance improvement.Integrating HIIT into stroke rehabilitation protocols is strongly recommended to promote functional independence.展开更多
Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts...Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.展开更多
In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and e...In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and environmental protection.As a result,coal mine filling mining technology has emerged,which can effectively achieve the goal of controlling surface subsidence in practical applications,while also significantly improving the recovery rate of coal resources.Based on this,this study will first elaborate on the characteristics of filling mining technology,and then analyze the key points of the application of supporting technology for mechanical and electrical equipment in the corresponding working face based on actual cases,in order to provide support for improving the efficiency of coal mining.展开更多
Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of ...Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of steeply inclined coal mine underground reservoirs(SICMUR),which is a paradigm shift from conventional CMUR that the coal seam itself serves as the reservoir floor,challenging conventional designs due to depth-dependent permeability and mechanical constraints.Triaxial mechanical-seepage tests on Xinjiang Wudong coal samples(100,200,300 m depths) revealed a 3.5 MPa triaxial strength increase per 100 m depth and a 58-fold post-peak permeability surge at 300 versus 100 m.Similar model simulations revealed mining-induced stress redistribution and significant deformation effects,particularly subsidence and water-conducting fractures during lower coal seam mining.Results indicate a minimum 40 m safety distance between reservoirs and lower coal seams.Critical construction parameters were investigated for Wudong mine SICMUR as collapse zone heights(9.9–12.31 m) and waterconducting fracture zone heights(31.96–37.40 m).This work systematically bridges SICMUR concepts to field implementation,offering a framework for water preservation in steeply inclined mining while addressing safety concerns,providing a new approach for water reservation in steeply inclined coal mining.展开更多
Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and th...Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.展开更多
Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method ...Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps展开更多
Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic pr...Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic principles and methods for mining pressure monitoring were analyzed and established. And the characteristics of overburden strata movement were analyzed by monitoring the support resistance of hydraulic support, the dynamic subsidence of immediate roof, the stress of backfill body, the front abutment pressure, and the mass ratio of cut coal to backfilled materials. On-site strata behavior measurements of 7403 W solid backfilling working face in Zhai Zhen Coal Mine show that the backfill body can effectively support the overburden load, obviously control the overburden strata movement, and weaken the strata behaviors distinctly. Specific performances are as follows. The support resistance decreases obviously; the dynamic subsidence of immediate roof keeps consistent to the variation of backfill body stress, and tends to be stable after the face retreating to 120-150 m away from the cut. The peak value of front abutment pressure arises at 5-12 m before the operating face, and mass ratio is greater than the designed value of 1.15, which effectively ensures the control of strata movement. The research results are bases for intensively studying basic theories of solid backfill mining strata behaviors and its control, and provide theoretical guidance for engineering design in FMSBM.展开更多
Fully mechanized mining(FMM)technology has been applied in Chinese coal mines for more than 40 years.At present,the output of a FMM face has reached 10-million tons with Chinese-made equipment.In this study,the new de...Fully mechanized mining(FMM)technology has been applied in Chinese coal mines for more than 40 years.At present,the output of a FMM face has reached 10-million tons with Chinese-made equipment.In this study,the new developments in FMM technology and equipment in Chinese coal mines during past decades are introduced.The automatic FMM technology for thin seams,complete sets of FMM technology with ultra large shear height of 7 m for thick seams,complete sets of fully mechanized top coal caving technology with large shear height for ultra-thick seams of 20 m,complete sets of FMM technology for complex and difficult seams,including steeply inclined seams,soft coal seams with large inclination angle,and the mechanized filling mining technology and equipment are presented.Some typical case studies are also introduced.Finally,the existing problems with the FMM technology are discussed,and prospect of FMM technology and equipment applied in Chinese coal mines is put forward.展开更多
Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the de...Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.展开更多
The exploration of undersea resources becomes popular as land resources decrease. Researches were conducted with emphasis on the safety and efficiency of undersea mining of the large gold deposit in Xinli District of ...The exploration of undersea resources becomes popular as land resources decrease. Researches were conducted with emphasis on the safety and efficiency of undersea mining of the large gold deposit in Xinli District of Sanshandao Gold Mine. A series of tests for the physical and mechanical characteristics of rock mass were carried out, and the three-dimensional geo-stress distribution was tested in the mining area. Further, a similar experimental simulation platform, which revealed the mechanism of water inrush and ascertained the reason- able thickness of the safety isolate layer, was established for the undersea mining. Meanwhile, the feasibility of cancelling the ore pillars and the safety conditions was checked by numerical simulation. The simulation results show that it is safe to exploit the ore body below the -85 m level （presently, the exploitation level is below -160 m in Xinli District）, and the ore pillars can be cancelled below the -560 m level. Fur- thermore, a novel backfill method was designed to reduce the rock strata disturbance and settlement, and the settlement of roof strata was monitored during the mining process. Engineering practice shows that the settlement of roof strata was small and that no disaster happened. This indicates that the undersea safety mining technology of the large gold deposit is achieved in Xinli District.展开更多
Innovations of mining technologies were proposed by beneficial utilizations of unfavorable factors such as high geostress,high geotemperature and high mining depth to achieve green mining as mining depth increases ine...Innovations of mining technologies were proposed by beneficial utilizations of unfavorable factors such as high geostress,high geotemperature and high mining depth to achieve green mining as mining depth increases inevitably.Cuttability of deep hard rock was investigated by experimental and regressed analyses to find the reasonable stress adjustment method to improve non-explosive mechanized fragmentation for hard ore-rock.A non-explosive mechanized and intellectualized mining method was proposed to continuously and precisely exploit phosphate underground,which promoted the high-recovery,low-waste and high-efficiency exploitation of phosphate with recovery rate over 90%,dilution rate near 5%and cutting efficiency about 107.7 t/h.A circular economy model and the backfill system were proposed to conduct resource utilizations of solid waste,by which the utilization amount of waste increased year after year.In 2018,the utilization amounts of phosphogypsum,yellow phosphorus slag and waste rock increased to 1853.6×10^3 t/a,291.1×10^3 t/a and 1493.8×10^3 t/a,respectively.展开更多
AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC pa...AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC patients were listed for liver transplantation(UCSF criteria).The median waiting time for transplantation was 9.5 mo.Twenty-nine patients received transarterial chemoembolization(TACE) as a bringing therapy and 16 patients received no treatment before transplantation.Five patients received HIFU ablation as a bridging therapy.Another five patients with the same tumor staging(within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison.Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores,tumor size and number,and cause of cirrhosis.RESULTS:The HIFU group and TACE group showed no difference in terms of tumor size and tumor number.One patient in the HIFU group and no patient in the TACE group had gross ascites.The median hospital stay was 1 d(range,1-21 d) in the TACE group and two days(range,1-9 d) in the HIFU group(P < 0.000).No HIFU-related complication occurred.In the HIFU group,nine patients(90%) had complete response and one patient(10%) had partial response to the treatment.In the TACE group,only one patient(3%) had response to the treatment while 14 patients(48%) had stable disease and 14 patients(48%) had progressive disease(P = 0.00).Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list(P = 0.559).CONCLUSION:HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis.It may reduce the drop-out rate of liver transplant candidate.展开更多
BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This stu...BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer.展开更多
Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a ...Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a myriad of factors during exercise, termed "myokines". The purpose of this study was to examine the effects of high-intensity interval training(HIIT) on the acute regulation of the mRNA expression of several myokines, including the prototypical myokine interleukin-6(IL-6), and recently identified myokines fibronectin type III domain-containing protein 5(FNDC5)(irisin) and meteorin-like protein(METRNL).Methods: Both before and after a 20-day period of twice-daily high-volume HIIT, 9 healthy males(20.5 ± 1.5 years performed a standardized bout of high-intensity interval exercise(HIIE; 5 × 4 min at ~80% pretraining peak power output) with skeletal muscle biopsy samples(vastus lateralis) obtained at rest, immediately following exercise, and at 3 h recovery.Results: Before training, a single bout of HIIE increased IL-6(p < 0.05) and METRNL(p < 0.05) mRNA expression measured at 3 h recovery when compared to rest. Following 20 days of HIIT, IL-6 and FNDC5 mRNA were increased at 3 h recovery from the standardized HIIE bout when compared to rest(both p < 0.05). Resting METRNL and FNDC5 mRNA expression were higher following training(p < 0.05), and there was an overall increase in FNDC5 mRNA post-training(main effect of training, p < 0.05).Conclusion: In human skeletal muscle(1) an acute bout of HIIE can induce upregulation of skeletal muscle IL-6 mRNA both before and after a period of intensified HIIT;(2) Resting and overall FNDC5 mRNA expression is increased by 20 days of HIIT; and(3) METRNL mRNA expression is responsive to both acute HIIE and short-term intense HIIT. Future studies are needed to confirm these findings at the protein and secretion level in humans.展开更多
AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)wi...AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.展开更多
The results from a number of investigations and fire experiments are presented and analyzed in order to characterize the fire behavior of mining vehicles in underground hard rock mines. The analysis also includes fire...The results from a number of investigations and fire experiments are presented and analyzed in order to characterize the fire behavior of mining vehicles in underground hard rock mines. The analysis also includes fire safety and fire protection measures with respect to the mining vehicle fire behavior.Earlier studies on fires in underground hard rock mines have shown that vehicles or mobile equipment are the dominant sources of fire. A better knowledge about the fire behavior of vehicles in underground hard rock mines is therefore needed. During the analysis the direction and flow rate of the ventilation in a drift was found to have a significant impact on the fire behavior, causing for example flame tilt with rapid fire spread. The shielded sections of a vehicle will be less affected by the ventilation flow resulting in for example a decreased flame spread. It was also found that spray fires may result in considerable heat release rate but are generally of shorter duration and will not make any significant contributions to the overall heat release rate of the fully developed vehicle fire. The fire duration of a loader tire from a full-scale fire experiment was found to be at least 200 min and will largely determine the total fire duration of the vehicle. A different scenario with different conditions with for example a slower flame spread resulted in an even longer fire duration. The radiative and convective fraction will be a key factor when determining the heat transfer mechanisms involved in a fire and will vary from material to material.Calculations show that the radiative fraction of the tire fires on two mining vehicles is significantly lower than found in earlier experiments. The design and construction of the mining vehicle will have an important impact on the fire behavior and could possibly mitigate the consequences of a fire and allow fire personnel to extinguish a fire that otherwise would have had a too high heat release rate.展开更多
文摘In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard.
基金supported by the National Natural Science Foundation of China (No.51774111)Henan province science and technology innovation outstanding talent fund of China (No.184200510003)
文摘The height of fractured zone(HFZ) at the high-intensity longwall mining panel plays a vital role in the safety analysis of coal mining under bodies of water. This paper described definitions of the highintensity mining. The processes of overburden failure transfer(OFT) were analyzed, which were divided into the development stage and the termination stage. Through theoretical analysis, the limited suspension-distance and the limited overhanging distance were proposed to judge the damage of each stratum. Mechanical models of strata suspended integrity and overhanging stability were established.A theoretical method to predict the HFZ at the high-intensity longwall mining panel was put forward based on the processes of OFT. Taking a high-intensity longwall mining panel(No. 11915 panel) as an example, the theoretical method proposed, the engineering analogy and the empirical formulas in the Regulation were used to predict the HFZ. The results show that the theoretical result is consistent with the engineering analogies' result and empirical formulas' result. The rationality and reliability of the theoretical method proposed is verified.
文摘Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts.
文摘High-intensity interval training(HIIT),a highly efficient and distinctive exercise format,has sparked growing academic interest in sports performance training.This article synthesizes theoretical and applied evidence to analyze mechanisms of HIIT in neuromuscular activation,hormonal responses,muscle fiber adaptation,and metabolic pathway effects.It focuses on its effectiveness in enhancing explosive power,maximum strength,and strength endurance,while also examining the integration of HIIT with traditional resistance training,periodized programming,and personalized prescription.Scientific implementation of HIIT can effectively diversify or even replace conventional strength training,not only offering positive directional changes for strength development but also introducing innovative approaches to sports performance training practices.
文摘[Objectives]To synthesize evidence on HIIT versus moderate-intensity continuous training(MICT)or routine rehabilitation in stroke survivors.[Methods]We systematically searched 8 databases(PubMed,EMBASE,CENTRAL,Web of Science,SPORTSDiscus,PsycINFO,SCOPUS,CINAHL)up to May 2025.Seventeen randomized controlled trials(RCTs;total n=1142)met inclusion criteria:adults with stroke,device-based HIIT(≥70%HRR/VO 2peak),and outcomes assessing VO_(2)peak,6-min walk distance(6MWD),or Berg Balance Scale(BBS).Methodological quality was evaluated using the PEDro scale.Pooled effect sizes(Hedges'g)were calculated via random-effects models,with heterogeneity quantified by I^(2).[Results]HIIT significantly improved peak oxygen uptake(VO_(2)peak)versus controls(g=0.59,95%CI:0.44-0.75,p<0.001;I^(2)=16.29%).Low heterogeneity and symmetrical funnel plots supported robustness.HIIT also enhanced walking endurance(6MWD:g=0.32,95%CI:0.16-0.48,p<0.01;I^(2)=30%).In contrast,no significant benefit was observed for balance function(BBS:g=0.07,95%CI:-0.13-0.26,p=0.50;I^(2)=0%).[Conclusions]HIIT is a safe and highly effective intervention for enhancing aerobic capacity and walking function post-stroke.Its benefits are maximized at higher intensities and longer durations but do not extend to balance improvement.Integrating HIIT into stroke rehabilitation protocols is strongly recommended to promote functional independence.
基金supported by Technology Innovation Fund of China Coal Research Institute(2022CX-I-04)Science and Technology Innovation Venture Capital Project of China Coal Technology Engineering Group(2020-2-TD-CXY005)。
文摘Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.
文摘In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and environmental protection.As a result,coal mine filling mining technology has emerged,which can effectively achieve the goal of controlling surface subsidence in practical applications,while also significantly improving the recovery rate of coal resources.Based on this,this study will first elaborate on the characteristics of filling mining technology,and then analyze the key points of the application of supporting technology for mechanical and electrical equipment in the corresponding working face based on actual cases,in order to provide support for improving the efficiency of coal mining.
基金supported by Beijing Natural Science Foundation (No.8254049)the National Natural Science Foundation of China (No.52374139)the Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project (No.2024ZD1004505)。
文摘Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of steeply inclined coal mine underground reservoirs(SICMUR),which is a paradigm shift from conventional CMUR that the coal seam itself serves as the reservoir floor,challenging conventional designs due to depth-dependent permeability and mechanical constraints.Triaxial mechanical-seepage tests on Xinjiang Wudong coal samples(100,200,300 m depths) revealed a 3.5 MPa triaxial strength increase per 100 m depth and a 58-fold post-peak permeability surge at 300 versus 100 m.Similar model simulations revealed mining-induced stress redistribution and significant deformation effects,particularly subsidence and water-conducting fractures during lower coal seam mining.Results indicate a minimum 40 m safety distance between reservoirs and lower coal seams.Critical construction parameters were investigated for Wudong mine SICMUR as collapse zone heights(9.9–12.31 m) and waterconducting fracture zone heights(31.96–37.40 m).This work systematically bridges SICMUR concepts to field implementation,offering a framework for water preservation in steeply inclined mining while addressing safety concerns,providing a new approach for water reservation in steeply inclined coal mining.
基金Project(10872218) supported by the National Natural Science Foundation of ChinaProject(2010CB732004) supported by the National Key Basic Research Program of China+1 种基金Project(20090461022) supported by the National Postdoctoral Foundation of ChinaProject (11MX21) supported by the Students' Innovation Project Aubsidize Award of Arcelor Mittal
文摘Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining.
基金Projects (50934006, 51074178) supported by the National Natural Science Foundation of ChinaProject (2010QZZD001) supported by the Fundamental Research Funds for the Central Universities of China
文摘Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps
基金Project(SKLCRSM12X01)supported by State Key Laboratory of Coal Resources and Safe Mining,China University of Mining&TechnologyProject(2014ZDPY02)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(CXLX13_951)supported by the Research Innovation Program for College Graduates of Jiangsu Province,China
文摘Fully mechanized solid backfill mining(FMSBM) technology adopts dense backfill body to support the roof. Based on the distinguishing characteristics and mine pressure control principle in this technology, the basic principles and methods for mining pressure monitoring were analyzed and established. And the characteristics of overburden strata movement were analyzed by monitoring the support resistance of hydraulic support, the dynamic subsidence of immediate roof, the stress of backfill body, the front abutment pressure, and the mass ratio of cut coal to backfilled materials. On-site strata behavior measurements of 7403 W solid backfilling working face in Zhai Zhen Coal Mine show that the backfill body can effectively support the overburden load, obviously control the overburden strata movement, and weaken the strata behaviors distinctly. Specific performances are as follows. The support resistance decreases obviously; the dynamic subsidence of immediate roof keeps consistent to the variation of backfill body stress, and tends to be stable after the face retreating to 120-150 m away from the cut. The peak value of front abutment pressure arises at 5-12 m before the operating face, and mass ratio is greater than the designed value of 1.15, which effectively ensures the control of strata movement. The research results are bases for intensively studying basic theories of solid backfill mining strata behaviors and its control, and provide theoretical guidance for engineering design in FMSBM.
文摘Fully mechanized mining(FMM)technology has been applied in Chinese coal mines for more than 40 years.At present,the output of a FMM face has reached 10-million tons with Chinese-made equipment.In this study,the new developments in FMM technology and equipment in Chinese coal mines during past decades are introduced.The automatic FMM technology for thin seams,complete sets of FMM technology with ultra large shear height of 7 m for thick seams,complete sets of fully mechanized top coal caving technology with large shear height for ultra-thick seams of 20 m,complete sets of FMM technology for complex and difficult seams,including steeply inclined seams,soft coal seams with large inclination angle,and the mechanized filling mining technology and equipment are presented.Some typical case studies are also introduced.Finally,the existing problems with the FMM technology are discussed,and prospect of FMM technology and equipment applied in Chinese coal mines is put forward.
基金Project(40901217)supported by the National Natural Science Foundation of China
文摘Suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.
基金financially supported by the National Basic Research and Development Program of China (No. 2010CB732004)Joint Funding of the National Natural Science Foundation and Shanghai Baosteel Group Corporation (No. 51074177)
文摘The exploration of undersea resources becomes popular as land resources decrease. Researches were conducted with emphasis on the safety and efficiency of undersea mining of the large gold deposit in Xinli District of Sanshandao Gold Mine. A series of tests for the physical and mechanical characteristics of rock mass were carried out, and the three-dimensional geo-stress distribution was tested in the mining area. Further, a similar experimental simulation platform, which revealed the mechanism of water inrush and ascertained the reason- able thickness of the safety isolate layer, was established for the undersea mining. Meanwhile, the feasibility of cancelling the ore pillars and the safety conditions was checked by numerical simulation. The simulation results show that it is safe to exploit the ore body below the -85 m level （presently, the exploitation level is below -160 m in Xinli District）, and the ore pillars can be cancelled below the -560 m level. Fur- thermore, a novel backfill method was designed to reduce the rock strata disturbance and settlement, and the settlement of roof strata was monitored during the mining process. Engineering practice shows that the settlement of roof strata was small and that no disaster happened. This indicates that the undersea safety mining technology of the large gold deposit is achieved in Xinli District.
基金Projects(41630642,51904335,51904333)supported by the National Natural Science Foundation of China
文摘Innovations of mining technologies were proposed by beneficial utilizations of unfavorable factors such as high geostress,high geotemperature and high mining depth to achieve green mining as mining depth increases inevitably.Cuttability of deep hard rock was investigated by experimental and regressed analyses to find the reasonable stress adjustment method to improve non-explosive mechanized fragmentation for hard ore-rock.A non-explosive mechanized and intellectualized mining method was proposed to continuously and precisely exploit phosphate underground,which promoted the high-recovery,low-waste and high-efficiency exploitation of phosphate with recovery rate over 90%,dilution rate near 5%and cutting efficiency about 107.7 t/h.A circular economy model and the backfill system were proposed to conduct resource utilizations of solid waste,by which the utilization amount of waste increased year after year.In 2018,the utilization amounts of phosphogypsum,yellow phosphorus slag and waste rock increased to 1853.6×10^3 t/a,291.1×10^3 t/a and 1493.8×10^3 t/a,respectively.
文摘AIM:To analyze whether high-intensity focused ultrasound(HIFU) ablation is an effective bridging therapy for patients with hepatocellular carcinoma(HCC).METHODS:From January 2007 to December 2010,49 consecutive HCC patients were listed for liver transplantation(UCSF criteria).The median waiting time for transplantation was 9.5 mo.Twenty-nine patients received transarterial chemoembolization(TACE) as a bringing therapy and 16 patients received no treatment before transplantation.Five patients received HIFU ablation as a bridging therapy.Another five patients with the same tumor staging(within the UCSF criteria) who received HIFU ablation but not on the transplant list were included for comparison.Patients were comparable in terms of Child-Pugh and model for end-stage liver disease scores,tumor size and number,and cause of cirrhosis.RESULTS:The HIFU group and TACE group showed no difference in terms of tumor size and tumor number.One patient in the HIFU group and no patient in the TACE group had gross ascites.The median hospital stay was 1 d(range,1-21 d) in the TACE group and two days(range,1-9 d) in the HIFU group(P < 0.000).No HIFU-related complication occurred.In the HIFU group,nine patients(90%) had complete response and one patient(10%) had partial response to the treatment.In the TACE group,only one patient(3%) had response to the treatment while 14 patients(48%) had stable disease and 14 patients(48%) had progressive disease(P = 0.00).Seven patients in the TACE group and no patient in the HIFU group dropped out from the transplant waiting list(P = 0.559).CONCLUSION:HIFU ablation is safe and effective in the treatment of HCC for patients with advanced cirrhosis.It may reduce the drop-out rate of liver transplant candidate.
基金supported by grants from the Ministry of Health Research Foundation(WKJ2006-1-007)the Hunan Provincial National Science Foundation (11JJ5060)
文摘BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer.
基金supported by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant (No. RGPIN 435807-13) to JPLthe ANZ-MASON foundation (to DB)supported by a Canadian Institutes of Health Research (CIHR) New Investigator Award (No. MSH-141980)
文摘Background: Exercise promotes numerous phenotypic adaptations in skeletal muscle that contribute to improved function and metabolic capacity. An emerging body of evidence suggests that skeletal muscle also releases a myriad of factors during exercise, termed "myokines". The purpose of this study was to examine the effects of high-intensity interval training(HIIT) on the acute regulation of the mRNA expression of several myokines, including the prototypical myokine interleukin-6(IL-6), and recently identified myokines fibronectin type III domain-containing protein 5(FNDC5)(irisin) and meteorin-like protein(METRNL).Methods: Both before and after a 20-day period of twice-daily high-volume HIIT, 9 healthy males(20.5 ± 1.5 years performed a standardized bout of high-intensity interval exercise(HIIE; 5 × 4 min at ~80% pretraining peak power output) with skeletal muscle biopsy samples(vastus lateralis) obtained at rest, immediately following exercise, and at 3 h recovery.Results: Before training, a single bout of HIIE increased IL-6(p < 0.05) and METRNL(p < 0.05) mRNA expression measured at 3 h recovery when compared to rest. Following 20 days of HIIT, IL-6 and FNDC5 mRNA were increased at 3 h recovery from the standardized HIIE bout when compared to rest(both p < 0.05). Resting METRNL and FNDC5 mRNA expression were higher following training(p < 0.05), and there was an overall increase in FNDC5 mRNA post-training(main effect of training, p < 0.05).Conclusion: In human skeletal muscle(1) an acute bout of HIIE can induce upregulation of skeletal muscle IL-6 mRNA both before and after a period of intensified HIIT;(2) Resting and overall FNDC5 mRNA expression is increased by 20 days of HIIT; and(3) METRNL mRNA expression is responsive to both acute HIIE and short-term intense HIIT. Future studies are needed to confirm these findings at the protein and secretion level in humans.
基金Supported by The cancer research project group of Tokyo Medical University
文摘AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.
文摘The results from a number of investigations and fire experiments are presented and analyzed in order to characterize the fire behavior of mining vehicles in underground hard rock mines. The analysis also includes fire safety and fire protection measures with respect to the mining vehicle fire behavior.Earlier studies on fires in underground hard rock mines have shown that vehicles or mobile equipment are the dominant sources of fire. A better knowledge about the fire behavior of vehicles in underground hard rock mines is therefore needed. During the analysis the direction and flow rate of the ventilation in a drift was found to have a significant impact on the fire behavior, causing for example flame tilt with rapid fire spread. The shielded sections of a vehicle will be less affected by the ventilation flow resulting in for example a decreased flame spread. It was also found that spray fires may result in considerable heat release rate but are generally of shorter duration and will not make any significant contributions to the overall heat release rate of the fully developed vehicle fire. The fire duration of a loader tire from a full-scale fire experiment was found to be at least 200 min and will largely determine the total fire duration of the vehicle. A different scenario with different conditions with for example a slower flame spread resulted in an even longer fire duration. The radiative and convective fraction will be a key factor when determining the heat transfer mechanisms involved in a fire and will vary from material to material.Calculations show that the radiative fraction of the tire fires on two mining vehicles is significantly lower than found in earlier experiments. The design and construction of the mining vehicle will have an important impact on the fire behavior and could possibly mitigate the consequences of a fire and allow fire personnel to extinguish a fire that otherwise would have had a too high heat release rate.
