scholarly journals A Novel Comprehensive Evaluation Method of Forest State Based on Unit Circle

Forests ◽  
2018 ◽  
Vol 10 (1) ◽  
pp. 5
Author(s):  
Ganggang Zhang ◽  
Gangying Hui ◽  
Gongqiao Zhang ◽  
Yanbo Hu ◽  
Zhonghua Zhao

Comprehensive evaluation of forest state is the precondition and critical step for forest management. To solve the problem that the radar plot and unit circle only focus on the value of each the evaluation index, this paper proposes a novel method for comprehensively and simultaneously evaluating the functionality and inhomogeneity of forest state based on the modified unit circle method. We evaluated the forest state of the Quercus aliena BL. var. acuteserrata Maxim. ex Wenz. broad-leaved mixed forest in the Xiaolong Mountains Forest Area of Gansu Province and the Pinus koraiensis Sieb. et Zucc. broad-leaved mixed forest in Jilin Province in China. According to the principle of comprehensive, scientific and operability, 10 evaluation indices on forest structure and vitality were selected to construct the evaluation indicator system. Each index was normalized based on the assignment method and ensured to be strictly positive based on reciprocal transformation method. The areas and arc length of the closed graph, formed by connecting every two adjacent indicators, in the radar plot and unit circle were extracted. Based on the isoperimetric theorem (isoperimetric inequality), a comprehensive evaluation model was constructed. Compared with radar chart and unit circle method, each index in the newly proposed unit circle method is represented by an independent sector region, reflecting the contribution of the index to the overall evaluation result. Each index has the same relative importance weight, contributing to the estimation the relative sizes of each aspect of forest state. The unique area and arc length of the closed graph help summarize the overall performance with a global score. The expression effect of improved unit circle has been enhanced, and as an English proverb put it, “A picture is worth a thousand words.” The new proposed method simultaneously evaluates the functionality and inhomogeneity of the forest state and it is a powerful tool for the diagnosis of forest state problems and the decision-making of forest management.

2013 ◽  
Vol 295-298 ◽  
pp. 2493-2499 ◽  
Author(s):  
Jin Yang ◽  
Ya Xian Wu ◽  
Chao Xia

An indicator system is established for the suitability of projects linked to the increase/decrease in urban and rural construction land based on the field surveys for the old areas to be dismantled in three administrative villages such as Niulandian Village, Tianjiagou Village and Nanchongsi Village of Tianchi Town in Lezhi County of Sichuan Province, and the fuzzy comprehensive evaluation method is used to evaluate indicators. The analysis of evaluation results provides reference for the efficient implementation of projects linked to the increase/decrease in urban and rural construction land.


2020 ◽  
Vol 3 (1) ◽  
pp. 25
Author(s):  
David Candel-Pérez ◽  
J. Bosco Imbert ◽  
Maitane Unzu ◽  
Juan A. Blanco

The promotion of mixed forests represents an adaptation strategy in forest management to cope with climate change. The mixing of tree species with complementary ecological traits may modify forest functioning regarding productivity, stability, or resilience against disturbances. Litter decomposition is an important process for global carbon and nutrient cycles in terrestrial ecosystems, also affecting the functionality and sustainability of forests. Decomposition of mixed-leaf litters has become an active research area because it mimics the natural state of leaf litters in most forests. Thus, it is important to understand the factors controlling decomposition rates and nutrient cycles in mixed stands. In this study, we conducted a litter decomposition experiment in a Scots pine and European beech mixed forest in the province of Navarre (north of Spain). The effects of forest management (i.e., different thinning intensities), leaf litter types, and tree canopy on mass loss and chemical composition in such decomposing litter were analysed over a period of three years. Higher decomposition rates were observed in leaf litter mixtures, suggesting the existence of positive synergies between both pine and beech litter types. Moreover, a decomposition process was favoured under mixed-tree canopy patches. Regarding thinning treatments significant differences on decomposition rates disappeared at the end of the study period. Time influenced the nutrient concentration after the leaf litter incubation, with significant differences in the chemical composition between the different types of leaf litter. Higher Ca and Mg concentrations were found in beech litter types than in pine ones. An increase in certain nutrients throughout the decomposition process was observed due to immobilization by microorganisms (e.g., Mg in all leaf litter types, K only in beech leaves, P in thinned plots and under mixed canopy). Evaluating the overall response in mixed-leaf litters and the contribution of single species is necessary for understanding the litter decomposition and nutrient processes in mixed-forest ecosystems.


2012 ◽  
Vol 18 (4) ◽  
pp. 696-710 ◽  
Author(s):  
Peide Liu ◽  
Xingying Wu

According to the characteristics of human resources managers’ competency and the research of relevant literatures at home and abroad, a competency evaluation method of human resources managers based on multi-granularity linguistic variables and VIKOR method is proposed. Firstly, the evaluation indicator system based on the competency of human resources managers is constructed. Then, by converting the evaluation information of different experts in different granularity to the same granularity by two-semantics, the comprehensive evaluation values can be obtained by integrating information of different experts. Further, the objective weights of the evaluation indexes were determined by the entropy method and an evaluation method were proposed based on the VIKOR method. Finally, an application example is given to illustrate the evaluation procedures of the developed approach and to demonstrate their practicality and effectiveness.


2021 ◽  
pp. 1-18
Author(s):  
Xiaoqing Huang ◽  
Zhilong Wang ◽  
Shihao Liu

In order to solve the problem of health evaluation of CNC machine tools, an evaluation method based on grey clustering analysis and fuzzy comprehensive evaluation was proposed. The health status grade of in-service CNC machine tools was divided, and the performance indicator system of CNC machine tools was constructed. On the above basis, the relative importance of each performance and its indicators were combined, and grey clustering analysis and fuzzy comprehensive evaluation was utilized to evaluate the health status of in-service CNC machine tools to determine their health grade. The proposed health status evaluation method was applied to evaluate the health level of an in-service gantry CNC machine that can be used for the machining propellers, and the results shown that the health status of the whole gantry CNC machine tool is healthy. The proposed evaluation method provides useful references for further in-depth research on the health status analysis and optimization of CNC machine tools.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Ya-Nan Zhao ◽  
Kai-Wen Meng ◽  
Li Gao

To improve the technology of unmanned ground vehicles, it is necessary to conduct a proper evaluation on various technologies. Previous evaluation methods are mainly based on completion of the task; this may mislead most of teams of unmanned ground vehicles using a conservative strategy during the evaluation. In this paper, a new evaluation method is proposed. Based on typical working conditions including intersection, car-following, and obstacle-avoiding, the new evaluation indicator system is established, and the entropy-cost function method is applied to the comprehensive evaluation of unmanned ground vehicles. As reported in a numerical example, the proposed evaluation method can get a quantitative result that authentically reflects the intelligent behavior level of unmanned ground vehicles.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Lili Wan ◽  
Qiuping Peng ◽  
Tianci Zhang ◽  
Zhan Wang ◽  
Yong Tian

In order to clarify the comprehensive operational capabilities of the airport and better plan the sustainable development mode of the airport, this paper studies the evaluation method of airport environmental carrying capacity. First, this paper proposes the concept of airport environmental carrying capacity by taking into account the complex characteristics of airports affected by multiple factors and then selects 16 representative evaluation indicators to construct an indicator system based on the Driving Force-Pressure-State-Response (DPSR) framework. Finally, the accelerated genetic algorithm-projection pursuit model is established to model a comprehensive evaluation index, which is used to calculate the airport environmental carrying capacity (AECC). The results of the case study show that the AECC of Guangzhou Baiyun International Airport (CAN) decreased year by year from 2008 to 2017, which is in line with the coordinated development level of CAN. By analysing the changing mechanism of AECC and indicators, we get 6 key influencing indicators that led to the continuous decline of AECC and put forward some political suggestions to improve the AECC.


2011 ◽  
Vol 243-249 ◽  
pp. 6312-6318
Author(s):  
Ge Liu ◽  
Feng Li

According to the characteristics of subway construction in Tianjin, a risk assessment indicator system has been established in subway construction. On the basis of traditional AHP (Analytic Hierarchy Process), the introduction of the concept of triangular fuzzy numbers evaluates the weight of risk factors in a more accurate and objective way. Adopting a fuzzy comprehensive evaluation mathematical model, by constructing membership matrix, the metro construction is not difficult to quantify the risk factors with the scientific evaluation methods. It can be proved that fuzzy comprehensive evaluation method used in subway construction process is a scientific, effective evaluation method.


2018 ◽  
Vol 8 (9) ◽  
pp. 1564 ◽  
Author(s):  
Si Li ◽  
Dongxiao Niu ◽  
Luofei Wu

China’s electricity market is in the environment for a round of new electric power reform, energy planning and transformation and the carbon market construction. The current market players are in urgent need of implementing their own energy saving and emission reduction actions. Relatively extensive and systematic researches on the assessment of the energy saving and emission reduction effects for the power plants, power grid companies, and technical equipment have been carried out at home and abroad. However, there are still vacancies in the researches on those for electricity retailers emerged on the sales side. Based on the carding and analysis of related policies and guidance, in this paper, relevant indicators are considered to build the evaluation indicator system of the energy saving and emission reduction effects for electricity retailers. The combination weights are gained by means of analytic hierarchy process and entropy weight method. Then, after the combined empowerment of indicators, the multi-level fuzzy comprehensive evaluation of energy saving and emission reduction effects for electricity retailers is conducted. Finally, choosing 10 electricity retailers (numbered from A to J) as evaluation objects, this model is used for obtaining the evaluation results and ranking of energy saving and emission reduction effects of electricity retailers, which provides reasonable ideas for the construction of evaluation indicator system and effective comprehensive evaluation methods of energy saving and emission reduction effects for market players in the electricity sales side. The results of example analysis show that, from a single dimension, the best electricity retailers in market transactions, technical means, integrated energy services, management system, and social responsibilities are followed by B, J, D, G, C, or I. However, from a global perspective, the sorted evaluation results are D, J, I, A, H, G, E, B, F, and C, which reflects the overall energy saving and emission reduction effects of electricity retailers through the two-level fuzzy comprehensive evaluation.


2020 ◽  
Vol 20 (8) ◽  
pp. 3687-3696
Author(s):  
Xi Wang ◽  
Shuangyin Wang ◽  
Jiashuo Qi

Abstract Cross-regional water diversion projects usually face risks of hazards, in particular high risks of sudden landslides on the slopes of water supply open channels. Determining the hazard level rapidly after a hazard occurs plays a critical role in improving the efficiency of emergency response and recovering the water supply capacity of the projects. Through in-depth analysis of the factors that affect the severity of open-channel landslides, an indicator system for hazard assessment of open-channel landslides was established and the criteria for evaluation of different hazard levels were identified. Based on the hierarchy of the indicator system, a two-level fuzzy comprehensive evaluation model was established to assess the impact of indicators in the model on the hazard level of open-channel landslides, and the weight of each indicator was determined by the analysis hierarchy process. The linear function was used to calculate the membership degree of each indicator to determine the hazard level. A hazard scenario was created with the water diversion project from the Irtysh River to Urumqi as an example, and the two-level fuzzy comprehensive evaluation model was applied to conduct hazard assessment. The proposed method was confirmed to be reasonable and practical.


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