Evaluation Method of Urban Comprehensive Disaster-Carrying Capability Based on Fractal Theory

2011 ◽  
Vol 90-93 ◽  
pp. 3155-3160 ◽  
Author(s):  
Wei Wang ◽  
Jie Tian ◽  
Zhi Tao Wang ◽  
Xiao Dong Guo ◽  
Dong Hui Ma
Keyword(s):  
Evaluation Method ◽  
Fractal Theory ◽  
Fractal Dimensions ◽  
Assessment Method ◽  
Scientific Basis ◽  
Disaster Prevention ◽  
Actual Situation ◽  
Fractal Method ◽  
Characteristic Index ◽  
Fuzzy Assessment

In order to correctly evaluate urban comprehensive disaster-carrying capability and then to establish scientific basis for disaster prevention and reduction, a fractal method for urban comprehensive disaster-carrying capability is proposed on the basis of system principle which is that structure determines function. The fractal dimensions of 29 cities are calculated and analyzed. The results show that relative stronger, middling and weaker are respectively 13.79%, 65.52% and 20.69%, which are completely consistent with the actual situation. So the method can construct a characteristic index, and the main impact effects can be analyzed according to the result. Tested by examples together with the other two methods, i.e. the fuzzy assessment method and exponent method, the results verify effectively that this method is useful and feasible.

Research on Risk Assessment Method and System Development of Small Ammonia Refrigeration Units

2019 ◽  
Author(s):  
Xiang Li ◽  
Weihua Wang ◽  
Weike Jing ◽  
Jin Shi ◽  
Fakun Zhuang
Keyword(s):  
Risk Assessment ◽  
Evaluation Method ◽  
System Development ◽  
Correction Method ◽  
Assessment Method ◽  
Scientific Basis ◽  
Assessment System ◽  
Assessment Model ◽  
Mitigation Measures ◽  
Risk Assessment Method

Abstract In recent years, ammonia leakage accidents occur frequently, which causes a great concern in China. Based on traditional risk analysis methods and the equipment characteristics, a risk evaluation method for small ammonia refrigeration units is proposed. The method includes a risk assessment model based on area division, a failure probability assessment method based on expert scoring system, a failure consequence assessment method based on regional population density and consequence mitigation measures, and a HAZOP risk correction method. Based on the proposed method, a risk assessment system of small ammonia refrigeration units is developed. This risk assessment method and system will provide a scientific basis to carry out the cold storage management in China.

Optimization Algorithm of Resource Allocation Based on Fuzzy Assessment Method

2014 ◽  
Vol 556-562 ◽  
pp. 3896-3900
Author(s):  
Yao Lei Li ◽  
Cong Xian Wang ◽  
Zhen Jia Li
Keyword(s):  
Technology Education ◽  
Evaluation System ◽  
Evaluation Method ◽  
Assessment Method ◽  
Fuzzy Evaluation ◽  
Technology Evaluation ◽  
Educational Perspective ◽  
Set Up ◽  
Fuzzy Assessment ◽  
Technology Teaching

The technology teaching of university basketball general course is a focus which all sectors of the community should pay more attention. How will the technology teaching of university basketball general course carry out optimization of integration, to play the biggest role, is also the key point of this paper. This paper from the main content of post-modern education and university basketball general course technology teaching, to understand the current situation of university basketball education, and construct basketball general course technology evaluation system. At the same time, using fuzzy evaluation method to do statistical analysis on the situation of basketball general course technology education, and in a targeted manner to set up teaching mode of basketball general course technology under Post-modern educational perspective, use the society, network, universities' and other resources effectively, to sharing the resources, realize technology education and the optimization configuration of resource.

scholarly journals Research on Rapid Evaluation of Rock Mass Quality Based on Ultrasonic Borehole Imaging Technology and Fractal Method

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Yuezheng Zhang ◽  
Hongguang Ji ◽  
Wenguang Li ◽  
Kuikui Hou
Keyword(s):  
Rock Mass ◽  
Evaluation Method ◽  
Fractal Theory ◽  
Box Dimension ◽  
Fractal Method ◽  
Imaging Technology ◽  
Rock Mass Quality ◽  
Hole Wall ◽  
Structural Surface ◽  
Borehole Imaging

The distribution of discontinuities in the deep stratigraphic rock mass is random and irregular, and the spatial distribution has statistical self-similarity, which can be analyzed by fractal theory. The borehole wall image obtained based on the ultrasonic borehole imaging technology can clearly reflect the rich structural surface information such as the inclination, density, and crack width of the structural surface in the rock mass. Due to its inherent fractal characteristics, the fractal box dimension of the hole wall image can be used to describe the complexity of the structural surface. In the study, the fractal box dimension of the hole wall image and the RQD value of the rock mass are compared, and it is found that there is a linear correlation between the two. Therefore, the rock quality can be evaluated according to the fractal box dimension value of the hole wall image. Finally, a rapid quantitative evaluation method for rock mass quality classification is established based on ultrasonic borehole imaging technology and fractal method.

Research on Oil Depot Safety Evaluation Based on Dow Chemical Fire and Explosion Index Assessment Method

2013 ◽  
Vol 748 ◽  
pp. 1256-1261
Author(s):  
Shou Hui He ◽  
Han Hua Zhu ◽  
Shi Dong Fan ◽  
Quan Wen
Keyword(s):  
Production Management ◽  
Evaluation Method ◽  
Risk Index ◽  
Safety Evaluation ◽  
Assessment Method ◽  
Theoretical Ground ◽  
Potential Hazard ◽  
Process Unit ◽  
Safety Production ◽  
Fire And Explosion

At the present time, the Dow Chemical Fire and Explosion Index (F&EI) is a kind of risk index evaluation method that is comprehensively used in evaluating potential hazard, area of exposure, expected losses in case of fire and explosion, etc. As the research object to oil depot storage tank area, this article ultimately confirms establishing appropriate pattern of process unit as well as reasonable safety precautions compensating method, in order to insure the reasonableness of evaluating result, by means of selecting process unit, confirming material factor and compensating safety precautions, using F&EI method. This can provide the basis for theoretical ground in aspect of oil depot development and safety production management.

scholarly journals Dynamic characteristics and fractal representations of crack propagation of rock with different fissures under multiple impact loadings

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bing Sun ◽  
Shun Liu ◽  
Sheng Zeng ◽  
Shanyong Wang ◽  
Shaoping Wang
Keyword(s):  
Fractal Dimension ◽  
Crack Propagation ◽  
Crack Growth ◽  
Impact Test ◽  
Fractal Theory ◽  
Dynamic Change ◽  
Fractal Dimensions ◽  
Peak Stress ◽  
Dynamic Mechanical Properties ◽  
Gravitational Potential Energy

AbstractTo investigate the influence of the fissure morphology on the dynamic mechanical properties of the rock and the crack propagation, a drop hammer impact test device was used to conduct impact failure tests on sandstones with different fissure numbers and fissure dips, simultaneously recorded the crack growth after each impact. The box fractal dimension is used to quantitatively analyze the dynamic change in the sandstone cracks and a fractal model of crack growth over time is established based on fractal theory. The results demonstrate that under impact test conditions of the same mass and different heights, the energy absorbed by sandstone accounts for about 26.7% of the gravitational potential energy. But at the same height and different mass, the energy absorbed by the sandstone accounts for about 68.6% of the total energy. As the fissure dip increases and the number of fissures increases, the dynamic peak stress and dynamic elastic modulus of the fractured sandstone gradually decrease. The fractal dimensions of crack evolution tend to increase with time as a whole and assume as a parabolic. Except for one fissure, 60° and 90° specimens, with the extension of time, the increase rate of fractal dimension is decreasing correspondingly.

Research of Coal Pores and Integrity Evaluation Method Based on Fractal Theory

2014 ◽  
Vol 670-671 ◽  
pp. 258-262 ◽  
Author(s):  
Ji Li ◽  
Xin Wu
Keyword(s):  
Fractal Dimension ◽  
Coal Sample ◽  
Evaluation Method ◽  
Structural Integrity ◽  
Gas Adsorption ◽  
Fractal Theory ◽  
Physical And Mechanical Properties ◽  
Box Dimension ◽  
Sem Images ◽  
Sem Image

Coal is a natural porous media, its porosity and structural integrity influenced the gas adsorption and desorption characteristics greatly, as well as physical and mechanical properties of coal. Scanning electron microscopy (SEM) is applied to acquire SEM image of four kinds of coal samples at different zoom levels, and the box dimension can be worked out based on the pore preprocessing of SEM images. Then, the numerical value of box dimension is used to describe the development degree of the four kinds of coal sample and four development degrees’ sequence. At last, the intrinsic relevance between fractal dimension and other parameters is analyzed through mathematic method. The results show as follows: coal sample has self-similarity characteristic; the fractal dimension is related to both the total number of pores and porosity degree; the data of the coal pore, analyzed through fractal dimension, are consistent with that through traditional method; what’s more, fractal dimension has more advantages in describing accuracy and simplicity.

scholarly journals Development of Back-calculation Model for Aggregate Gradation Determination Using Fractal Theory

2018 ◽  
Vol 159 ◽  
pp. 01006
Author(s):  
Bagus Hario Setiadji ◽  
Supriyono ◽  
Djoko Purwanto
Keyword(s):  
Fractal Dimension ◽  
Fractal Theory ◽  
Asphalt Mixture ◽  
Fractal Dimensions ◽  
Calculation Model ◽  
Careful Consideration ◽  
Upper And Lower Bounds ◽  
Aggregate Gradation ◽  
Fractal Characteristic ◽  
Fractal Characteristics

Several studies have shown that fractal theory can be used to analyze the morphology of aggregate materials in designing the gradation. However, the question arises whether a fractal dimension can actually represent a single aggregate gradation. This study, which is a part of a grand research to determine aggregate gradation based on known asphalt mixture specifications, is performed to clarify the aforementioned question. To do so, two steps of methodology were proposed in this study, that is, step 1 is to determine the fractal characteristics using 3 aggregate gradations (i.e. gradations near upper and lower bounds, and middle gradation); and step 2 is to back-calculate aggregate gradation based on fractal characteristics obtained using 2 scenarios, one-and multi-fractal dimension scenarios. The results of this study indicate that the multi-fractal dimension scenario provides a better prediction of aggregate gradation due to the ability of this scenario to better represent the shape of the original aggregate gradation. However, careful consideration must be observed when using more than two fractal dimensions in predicting aggregate gradation as it will increase the difficulty in developing the fractal characteristic equations.

scholarly journals Evaluation of water resources carrying capacity based on cultivated land and urban construction scale -- a case study of Jinzhou City

2021 ◽  
Vol 248 ◽  
pp. 03010
Author(s):  
Gao Mengmeng ◽  
Li Xiaolei ◽  
Yang Nan ◽  
Sun Xiubo ◽  
Liu Qiong ◽  
...  
Keyword(s):  
Water Resources ◽  
Evaluation Method ◽  
Scientific Basis ◽  
Human Society ◽  
Cultivated Land ◽  
Urban Construction ◽  
Water Resources Carrying Capacity ◽  
Social And Economic Development ◽  
Survival And Development

Water resources play an important role in the natural environment, which is an irreplaceable resource for the survival and development of human society. Taking water resources as the research object, combined with the demand of social and economic development for water resources, this paper carried out the research on the evaluation method of cultivated land scale and urban construction scale under the constraints of water resources in Jinzhou. The results show that: the scale of cultivated land is 7215.98-7843.20km2, which is in surplus. Heishan County has the largest scale of cultivated land and Guta District has the smallest scale of cultivated land. The urban construction land scale is 229.89-279.02 km2, which is in surplus. Taihe District and Yixian County are overloaded, and the rest are surplus. The evaluation results can support the determination and decomposition of planning objectives and indicators, and provide an important scientific basis for the implementation of local land spatial planning.

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