scholarly journals Layout of the First-Mining Working Face in the Protected Seam for Pressure Relief by Peak Stress Shift

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Xiao-Xu Gao ◽  
Guo-Jin Chai ◽  
Guang-An Zhu
Keyword(s):  
Evaluation Method ◽  
Coal Pillar ◽  
Stress Transfer ◽  
Peak Stress ◽  
Infinite Plane ◽  
Horizontal Distance ◽  
Analytic Hierarchy ◽  
Working Face ◽  
Weighted Values ◽  
Hierarchy Process

An appropriate layout of the first-mining working face of protected seams is key to rockburst prevention in coal seams. By taking the first-mining working face in the 2-2# middle coal seam in Hulusu Coal Mine as the background, a mechanical model for the stress distribution after mining the upper protective seams was established through theoretical analysis and in situ measurement. The problem concerning the layout of the first-mining working face in the protected seam was transformed into one concerning the optimal horizontal distance L. Furthermore, based on the theory of stress transfer within a semi-infinite plane, the distribution of the vertical stress in the protected seam was deduced, for which numerical simulation was performed. Through calculation, it is best (in terms of roadway excavation) to set L to between 50 and 75 m; the mining-induced disturbance shows the least influence on the two roadways at L = 80 to 140 m and at L = 40 to 100 m, and the influence of the remaining coal pillar on mining of the working face is the least significant. Based on the analytic hierarchy process (AHP) evaluation method, the weights of three groups of contradictory criteria and the weighted values of the peak stress under different values of L were calculated. The results show that the global stress on the first-mining working face in the protected seams is lowest at L = 60 m. The results can provide a reference for the layout of the working faces in protected seams in adjacent coal mines.

Analysis of the Safety Factors of Municipal Road Undercrossing Existing Bridge Based on Fuzzy Analytic Hierarchy Process Methods

2021 ◽  
pp. 036119812110318
Author(s):  
Yonghong Yang ◽  
Yu Chen ◽  
Zude Tang
Keyword(s):  
Safety Assessment ◽  
Evaluation Method ◽  
Comprehensive Evaluation ◽  
Safety Evaluation ◽  
Safety Factors ◽  
Analytic Hierarchy ◽  
Road Engineering ◽  
Existing Bridges ◽  
Hierarchy Process ◽  
Engineering Projects

Increasing traffic volume and insufficient road lanes often require municipal roads to be reconstructed and expanded. Where a road passes under a bridge, the reconstruction and expansion project will inevitably have an impact on the bridge. To evaluate the safety impact of road engineering projects on bridges, this paper evaluates the safety of the roads and ancillary facilities of highway bridges involved in municipal road engineering projects. Based on a comprehensive analysis of the safety factors of municipal roads undercrossing existing bridges, a fuzzy comprehensive analytic hierarchy process (AHP) evaluation method for the influence of road construction on the safety of existing bridges is proposed. First, AHP is used to select 11 evaluation factors. Second, the target layer, criterion layer, and index layer of evaluation factors are established, then a safety evaluation factor system is formed. The three-scale AHP model is used to determine the weight of assessment indexes. Third, through the fuzzy comprehensive AHP evaluation model, the fuzzy hierarchical comprehensive evaluation is carried out for the safety assessment index system. Finally, the fuzzy comprehensive evaluation method is applied to the engineering example of a municipal road undercrossing an existing expressway bridge. The comprehensive safety evaluation of the existing bridge reflects the practicability and feasibility of the method. It is expected that, with further development, the method will improve the decision-making process in bridge safety assessment systems.

Integrated AHP-BPNN Model for Wind Farm Investment Evaluation

2014 ◽  
Vol 541-542 ◽  
pp. 966-971
Author(s):  
Xiang Feng Zhang ◽  
Tian Yu Liu ◽  
Bin Jiao
Keyword(s):  
Wind Farm ◽  
Evaluation Method ◽  
Back Propagation ◽  
Wind Farms ◽  
Back Propagation Neural Network ◽  
Analytic Hierarchy ◽  
Farm Investment ◽  
Hierarchy Process ◽  
Power Project ◽  
Bpnn Model

The construction of wind farms grows quickly in China. It is necessary for stakeholders to estimate investment costs and to make good decisions about a wind power project by making a budget for the investment. This paper proposed an evaluation method by integrating the analytic hierarchy process (AHP) with back-propagation neural network (BPNN) to evaluate wind farm investment. In the AHP-BPNN model, the AHP method is used to determine the factors of wind farm investment. The factors with high importance are reserved while those with low importance are eliminated, which can decrease the number of inputs of the BPNN. The experiment results show that the integrated model is feasible and effective.

Study of Evaluation Method in Terms of Structural Planes Mechanical Characteristics in Engineering Rock Mass

2013 ◽  
Vol 353-356 ◽  
pp. 384-387 ◽  
Author(s):  
Mu Dan Guo ◽  
Fu Sheng Zhu ◽  
Shu Hong Wang ◽  
Xi Jiang Mu
Keyword(s):  
Rock Mass ◽  
Stability Analysis ◽  
Efficient Method ◽  
Weight Distribution ◽  
Evaluation Method ◽  
Mechanical Characteristics ◽  
Significant Issue ◽  
Analytic Hierarchy ◽  
Intensity Parameters ◽  
Hierarchy Process

Study of mechanical characteristics of structural planes has been significant issue in engineering rock mass stability analysis. The factors that affect the mechanical behavior of structural planes are so complicated that it is quite essential to take an efficient method to quantificationally analyze these factors. Based on the basic principals of analytic hierarchy process (AHP), a structural plane classification method-CSPC method is proposed. It can conduct weight distribution in terms of the complicated factors, assess the structural planes comprehensively and also forecast the planes intensity parameters semiquantitatively. The classification and forecast parameters of structural planes appropriately fit the cases in engineering. Furthermore, the method is easy to master for the engineers and the application can be of great prospect.

scholarly journals A HYBRID MULTIPLE CRITERIA EVALUATION METHOD OF RANKING OF CULTURAL HERITAGE STRUCTURES FOR RENOVATION PROJECTS

2017 ◽  
Vol 21 (3) ◽  
pp. 318-329 ◽  
Author(s):  
Zenonas TURSKIS ◽  
Zydrune MORKUNAITE ◽  
Vladislavas KUTUT
Keyword(s):  
Cultural Heritage ◽  
Evaluation Method ◽  
Social Needs ◽  
Problem Solution ◽  
Analytic Hierarchy ◽  
State Institutions ◽  
The Social ◽  
Heritage Buildings ◽  
Multiple Criteria Evaluation ◽  
Hierarchy Process

Cultural heritage item preservation, renovation and adaptation to the social needs of people, as well as their passing from generation to generation, is a problem relevant from economic, historical, archeological, religious, technological, research and other perspectives. They are typical strategic multi-criteria decision-making problems. The state institutions and the owners and managers of the heritage items invest in their preservation. In fact, every country has a great number of the registered heritage structures. To ensure their effective management and renovation, a lot of implementation projects and strategies should be developed and evaluated. This work requires large investments and time. The paper presents a hybrid model developed for ranking the heritage buildings intended for renovation according to their value. The model for problem solution based on integrated using two MCDM methods Analytic Hierarchy Process and EDAS. A set of the criteria for evaluating the projects, concerning the renovation of cultural heritage items defined.

scholarly journals Deformation Law and Control Measures of Gob-Side Entry Filled with Gangue in Deep Gobs: A Case Study

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Xun Liu ◽  
Shihao Tu ◽  
Dingyi Hao ◽  
Yida Lu ◽  
Kaijun Miao ◽  
...  
Keyword(s):  
Coal Pillar ◽  
Stress Transfer ◽  
Control Measures ◽  
Theoretical Derivation ◽  
Simulation Research ◽  
Deformation Control ◽  
Deformation Problem ◽  
Working Face ◽  
Large Deformation Problem ◽  
Application Requirements

Aiming at the large deformation problem of gob-side entry in solid filling mining, the roof subsidence of gob-side entry retaining (GER) was studied under the influence of gangue filling, by taking a deep filling working face in Shandong Province as the engineering background and using theoretical derivation as well as FLAC3D numerical simulation. Research shows that the stiffness of the gangue filling body in the gob and the stiffness and width of the entry protection coal and rock mass (EPCARM) are positively correlated with the GER roof subsidence, which is much less affected by the EPCARM parameters than by the GER stiffness. The GER failure to meet the application requirements is mainly attributed to the insufficient stiffness of the gangue filling body and excessive advance subsidence, which inhibit the roof stress transfer. The GER replacement by the gob-side entry driving (GED) scheme, which implies replacing the entry protection gangue bag wall with the coal pillar with a width of 5 m, will reduce the roof subsidence to 0.114 m, according to the proposed equation. The results obtained are considered quite instrumental in deformation control of the gob-side entry filled with gangue, as well as substantiation of GED and GER applicability options.

AN INTEGRATED STRATEGIC APPROACH TO SUPPLIER EVALUATION AND SELECTION

2012 ◽  
Vol 11 (01) ◽  
pp. 55-76 ◽  
Author(s):  
REZA KHORRAMSHAHGOL
Keyword(s):  
Evaluation Method ◽  
Decision Makers ◽  
Supplier Evaluation ◽  
Analytic Hierarchy ◽  
Integrated Methodology ◽  
Strategic Approach ◽  
Index Matrix ◽  
Efficiency And Effectiveness ◽  
Aid Decision ◽  
Hierarchy Process

This paper, using goal programming (GP) and the analytic hierarchy process (AHP), proposes an integrated methodology to aid decision makers in (1) evaluating, screening and selecting best suppliers from among an exhaustive list of available suppliers and (2) determining the amount to be purchased from the selected suppliers. Along the supply chain, the suppliers, by being situated at the upstream of the chain, play a crucial role in successful management of the entire (subsequent) members of the chain and can have a significant impact on the efficiency and effectiveness of the activities of the rest of the chain, and ultimately, on the delivery of the desired products/services. Thus supplier selection can certainly contribute greatly to a firm's competitive advantage and its organizational success. This study suggests a screening and evaluation method, named supplier priority index matrix, to eliminate the least qualified suppliers and to choose the most promising ones. The remaining potential suppliers are evaluated and the best are selected from among them. Finally the AHP and GP are used to allocate the firm's total supplies among the chosen/selected suppliers.

Fire Risk Assessment of Fire Retardant Polyurethane Thermal Insulation Materials for Exterior Walls of Buildings Based on Analytical Hierarchy Process

2013 ◽  
Vol 785-786 ◽  
pp. 191-198
Author(s):  
Li Jun Li ◽  
Feng Li ◽  
Ze Jiang Zhang
Keyword(s):  
Thermal Insulation ◽  
Evaluation Method ◽  
Fire Hazard ◽  
Fire Retardant ◽  
Fire Risk ◽  
Insulation Material ◽  
Test Results ◽  
Analytic Hierarchy ◽  
Rigid Foam ◽  
Hierarchy Process

Different flame retardant contents of polyurethane rigid foam (PRF) were prepared in this paper. Combustion performances of PRF were tested by cone calorimeter (CONE). Fire risk of PRF was evaluated based on Analytic Hierarchy Process (AHP). The evaluation results were compared with the traditional LOI results. It was found that the evaluation method based on AHP combined with CONE test results for evaluating fire hazard of thermal insulation material for exterior walls of buildings is more accurate and objective compared with the method of the traditional LOI.

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