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Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The weathering at the top of bedrock in Jurassic coalfield in northern Shaanxi is strong, and the formed weathered bedrock aquifer is the main water filling source of the mine, which poses a serious threat to the safe mining of the mine. The scientific evaluation of the water abundance of the weathered bedrock aquifer and the advanced drainage of the areas with strong water abundance are essential measures for preventing and controlling water disasters of the roof weathered bedrock. In this paper, taking Nanliang Coal Mine as an example, according to the drilling data, the weathering index, core recovery rate, brittle-plastic rock thickness ratio and rock structure index are selected to construct the evaluation system. The fuzzy analytic hierarchy process and coefficient of variation method are used to weigh comprehensively, and the water abundance of weathered bedrock aquifer in Nanliang Coal Mine is evaluated. The results show that the weathering degree of bedrock in Nanliang Coal Mine is strongly affected by ancient terrain, and the underlying Quaternary gully controls the thickness of the bedrock weathering zone. Combined with the evaluation results of mine water inrush status, the water inflow in the water-rich area is large.

Flash floods are often sudden and destructive natural disasters triggered by heavy rainfall in small mountainous watersheds, which cause a great threat to the lives and property safety of local people. Previous flash flood studies are mostly based on single ditch and small watershed scales with mature assess system and models. How to assess flash flood hazards in the large-area mountain with diverse landforms and complex geological structures still need further exploration. Taking Longnan mountain area in Gansu Province, which is prone to flash floods, as an example, this paper introduces the flash flood potential index（FFPI） to build an evaluation system and framework in flash flood risk assessment. Firstly, the spatial distribution of FFPI in the study area is constructed by selecting slope, land use, soil texture and fractional vegetation cover（FVC）, combined with analytic hierarchy process（AHP） and information entropy. Secondly, the hazard and risk distribution of flash floods in the study area were obtained by introducing 0～24 h cumulative the maximum rainfall, rainy season average rainfall and flow accumulation as driving factors, and GDP and population density as hazard-bearing bodies. It is also verified with the historical flash flood data in this area. The results show that: the accuracy of using the FFPI model combined with AHP and information entropy to assess the risk of mountain flash floods in Longnan of Gansu Province is higher, and about 95.77% of the historical flash flood data are distributed in the medium, high and very high grades. From the perspective of administrative areas, the high and very high risk areas of flash floods in the study area are mainly distributed in Hanwang Town, Cheng County and Kang County of Wudu District, accounting for 31.5%, 28.3% and 18.1% respectively. And the low risk areas are mainly located in some areas of Li County, Zhouqu County and Wen County, accounting for 18.9%, 18.4% and 13.6% respectively. From the analysis of watershed scope, the high risk areas of flash floods in the study area are mainly concentrated in the downstream areas of rivers with gentle terrain, high population density and relatively developed economy, and the low risk areas are mainly located in the west and north of the study area with higher terrain. The research results are consistent with the field investigation of flash floods in the study area. The model constructed in this study and the credible assessment results can provide a reference and theoretical basis for flash floods prevention and hazard reduction and related research in Longnan mountain area of Gansu Province. [ABSTRACT FROM AUTHOR]

With the large-scale mining of deeply buried coal seams, the risk of roof water inrush increases during mining. In order to ensure safe mining, it is necessary to predict the risk potential of water inrush from the roof aquifer. This study introduces a coupling evaluation method, including the analytic hierarchy process (AHP), principal component analysis (PCA), and improved Game theory (IGT). This paper takes the water inrush from the roof aquifer of the 11-2 coal seam in Kouzidong mine as the research object. An evaluation index system is constructed by selecting six evaluation factors, including the aquitard effective thickness, aquiclude thickness, the ratio of sandstone to mudstone, rock quality designation, fault fractal dimension, and wash water quantity of geological log. The comprehensive weighting method based on IGT is used to optimize the subjective and objective weighting values obtained by AHP and PCA methods in turn, and an AHP–PCA–IGT evaluation model is established to divide and evaluate the water inrush risk zonation of the roof aquifer. The risk degree of the water inrush gradually decreases from the center to the north–south, and the main areas with relatively high risks and higher risks are distributed in a small part of the western and eastern regions. Finally, combining various drilling data examples, drilling pumping tests, and water inrush sites, the accuracy of the predicted results is validated through the vulnerability fitting percentage (VFP). The predictions are basically consistent with the actual results, and this study lays a theoretical foundation for the prevention and control of water inrush hazards. [ABSTRACT FROM AUTHOR]

The existing risk assessment model of water inrush from coal seam floor has the problems of weak generalization capability and low accuracy for the working face with complex geological structures. In order to solve the above problems, a risk assessment model of water inrush from coal seam floor based on comprehensive weighting by analytic hierarchy process (AHP) and improved entropy weight method (IEW) is proposed. Based on the unascertained measure of single index, the comprehensive weight of each assessment index affecting water inrush from coal seam floor is given by the AHP-IEW comprehensive weighting method. A comprehensive risk assessment model of water inrush from coal seam floor is established. The unascertained measure value of each assessment index is calculated by using the model. Then according to the recognition criteria of confidence, the grade is determined and the assessment result is obtained. The feasibility of the model is verified by taking 1305 working face of Pandao Coal Industry Co., Ltd. as the research object. ① According to the actual situation of the coal mine, the mining depth, coal seam thickness, coal seam dip angle, aquifer water pressure, effective water barrier thickness, floor brittle rock thickness, fault fractal dimension and floor integrity that affect the floor water inrush risk are selected as the assessment indexes. The graded standard of floor water inrush risk is established. ② The single index measure functions are constructed to obtain the measure value of each assessment index. ③ The comprehensive weight of each assessment index is obtained by AHP-IEW comprehensive weighting method. ④ The comprehensive measure assessment vector is determined by combining the comprehensive weight and the unascertained measure matrix of the assessment index. ⑤ According to the comprehensive measure assessment vector, the investigation points in the study area of the coal mine are classified into risk grades. The results are compared with the field investigation results. The verification results show that compared with IEW assessment results, the prediction accuracy of risk assessment model of water inrush from coal seam floor based on AHP-IEW comprehensive weighting is higher. The assessment results are consistent with the actual investigation situation in the mining process of the working face.

Power market evaluation can reflect the problems in market construction and operation, which is of great significance to the healthy development of power market and the improvement of market rules. Nowadays, several countries are still in the progress of power market liberalization, and an effective power market evaluation system has not been established. In this paper, a hierarchical evaluation system of power market is established according to the construction situation of the developing power markets, which includes market competition level, market operation level, market development level, market opening level and market efficiency level. Then, the Delphi method and the entropy method are used to comprehensively weight the index based on the multiple attribute decision-making theory, and radar charts are used to evaluate the power market. By using the proposed evaluation index and method, the operation condition of a provincial power market in China is analyzed.

This paper presents a method for evaluation floor water inrush risk using combined weighting and analytic hierarchy process. The method is validated by a case study at the Pengzhuang coal mine in Shandong Province, China. First, the relevant geological background, hydrogeological data and related data were collected and analyzed, and the risk evaluation index of water inrush from the floor was determined. Then, combined with principal component analysis, entropy weight method and analytic hierarchy process, a comprehensive evaluation model was constructed to determine the comprehensive weights of each surge evaluation index. Finally, based on the GIS geographic information processing system, the optimized comprehensive weighting mathematical model was combined with the vulnerability index method to determine the water inrush risk division. The results show that the improved integrated weighting model is more accurate than the improved comprehensive weighting model. At the same time, the evaluation results obtained by comparing the traditional water inrush coefficient method have verified the reasonableness of the evaluation model. The results can provide a theoretical basis for the safe mining of coal seam above confined groundwater. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to solve the problem of lack of learning evaluation information of single learning data, a learning evaluation with multi-source teaching data fusion was proposed. The correlation among different data sources was analyzed with Spearman and the relationship weight and optimization weight of each data source was calculated, by which the fusion calculation was done with comprehensive weighting. By such a way, the differences of students’ learning evaluation with different teaching methods can be balanced and the advantages and disadvantages of various learning styles can be fused. The results show that this method is effective, which is helpful for comprehensive learning evaluation and provides a basis for adaptive learning. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To ensure safe mining of the Taigemiao no. 3 mine field in Inner Mongolia, China, it is very important to make clear the roof aquifer water abundance distribution feature. On the basis of collecting the main controlling factors of aquifer water abundance from the geological and hydrogeological prospecting data of the study area, the no. 2 coal seam roof aquifer water abundance of Taigemiao no. 3 mine field was analyzed and evaluated using three methods. The first method is analytic hierarchy process (AHP)-type water-richness index method (AHP-type WIM) which is commonly used. But AHP is relatively subjective, so we trying to use a more objective method which is weighed gray relational degree method (WGRDM); this method mainly used pure data analyzing, it is better than AHP-type WIM but still not perfect, so the comprehensive weighted method (CWM) is put forward by adopting the advantage of the former two methods. In order to assess the accuracy rate of the three methods quantificationally, the evaluation results of the three methods are compared respectively with the measured unit water inflow which can directly reflect the aquifer water abundance, which shows that the WGRDM is more accurate than AHP-type WIM, and the CWM is more scientific and accurate in both weight calculation and water abundance grading. The superiority of CWM is more obvious when there are too many evaluation factors. [ABSTRACT FROM AUTHOR]