Technogenic Soils on Sand Opencast Mine Floor Drift and Spoils

Author(s):  
S. Kiss ◽  
D. Paşca ◽  
M. Drăgan-Bularda
Author(s):  
Z. Kaláb ◽  
J. Knejzlík ◽  
R. Kořínek ◽  
P. Žůrek ◽  
J. Doležal ◽  
...  
Keyword(s):  

Water ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1618 ◽  
Author(s):  
Dan Ma ◽  
Hongyu Duan ◽  
Xin Cai ◽  
Zhenhua Li ◽  
Qiang Li ◽  
...  

Water inrush hazards can be effectively reduced by a reasonable and accurate soft-measuring method on the water inrush quantity from the mine floor. This is quite important for safe mining. However, there is a highly nonlinear relationship between the water outburst from coal seam floors and geological structure, hydrogeology, aquifer, water pressure, water-resisting strata, mining damage, fault and other factors. Therefore, it is difficult to establish a suitable model by traditional methods to forecast the water inrush quantity from the mine floor. Modeling methods developed in other fields can provide adequate models for rock behavior on water inrush. In this study, a new forecast system, which is based on a hybrid genetic algorithm (GA) with the support vector machine (SVM) algorithm, a model structure and the related parameters are proposed simultaneously on water inrush prediction. With the advantages of powerful global optimization functions, implicit parallelism and high stability of the GA, the penalty coefficient, insensitivity coefficient and kernel function parameter of the SVM model are determined as approximately optimal automatically in the spatial dimension. All of these characteristics greatly improve the accuracy and usable range of the SVM model. Testing results show that GA has a useful ability in finding optimal parameters of a SVM model. The performance of the GA optimized SVM (GA-SVM) is superior to the SVM model. The GA-SVM enables the prediction of water inrush and provides a promising solution to the predictive problem for relevant industries.


Author(s):  
Bibhuti B. Mandal ◽  
Veena D. Manwar

Background: Low back pain (LBP) and degenerative changes in the spinal system are reportedly associated with exposure to low frequency (0.5- 80 Hz) whole-body vibration (WBV). The main objective of the study was to determine prevalence of musculoskeletal disorders among Heavy Earth Moving Machinery (HEMM) operators exposed to WBV in an opencast mine in western India.Methods: Forty six operators from an opencast mine were recruited as exposed group in a questionnaire based cross-sectional study. Twenty eight employees engaged in sedentary office work were taken as control. All subjects were asked about location and severity of body pain in the past 7 days and 12 months. A four point pain scale was used. Significance of difference of demographic / anthropometric parameters was studied using t-test of independent samples. Association between the pain type and exposure was obtained using Chi-square test. Risk of each type of pain was determined in terms of odds ratio. Adjusted estimate of ORs were obtained through logistic regression modelling, wherein the model fitness was judged using Hosmer-Lemeshow test.Results: The mean exposure duration was 11.30 ± 7.45 years. LBP was the most predominant MSD which showed highly significant association with exposure (P <0.001). Overall, the risk analysis revealed a significant increase in the likelihood of MSD due to exposure. 39% of the exposed group required medical attention.Conclusions: Based on subjective response of exposed group, it can be said that prevalence of musculoskeletal pain as manifestation of MSD due to exposure to WBV especially LBP is high among HEMM operators which affected their quality of life. 


Author(s):  
Monika Staniaszek-Kik

Abstract The present study reports new localities of four liverwort species, i.e., Fossombronia foveolata Lindb., Gymnocolea inflata (Huds.) Dumort., Leiomylia anomala (Hook.) J.J. Engel & Braggins and Odontoschisma denudatum (Mart.) Dumort., found in Central Poland. The new sites are situated in peat bog habitats and swamp forest in the depression cone of lignite opencast mine near Bełchatów in Central Poland. All of the reported species are very rare and have only few localities in Central Poland.


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