scholarly journals A comprehensive runoff variation evaluation system of the Yarlung Zangbo River based on vague sets

Author(s):  
Xiaolu Zhang ◽  
Linglei Zhang ◽  
Min Chen ◽  
Dian Li ◽  
Min Peng ◽  
...  

Abstract Runoff processes are the basis for maintaining the safety of river ecosystems. The Yarlung Zangbo River (YZR) faces changes in flow regimes due to the impacts of human activities and climate change#which may threaten its fragile ecosystem. In this study#a new comprehensive system for evaluating runoff variation was constructed to investigate the degree of runoff alternation in the YZR. Based on the data from the primary hydrological stations in the YZR from 1956 to 2000#the assessment indicators of runoff variation were selected by considering the flow#sediment#and water temperature processes. Furthermore#a comprehensive evaluation system for runoff variation was constructed via multiple hydrological analysis methods and vague sets. The results showed that the variation index of the YZR from 2010 to 2013 was 0.15–0.20 compared with the flow regimes of the YZR before 2000#which were within a reasonable range#indicating that the comprehensive runoff conditions of the YZR were not greatly disturbed by human activities such as reservoir construction and river regulation during this period. These results provide a tool for evaluating the runoff change in the YZR and new references for researching runoff variation in other similar watersheds.

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Qiang Huang ◽  
Jingjing Fan

The runoff change in Weihe River is significantly decreasing with the climate change and the huge increasing of human activities. The analysis of the variation changes of runoff would provide scientific understanding of Weihe River basin and similar basins. Mann-Kendall method is used to detect the variation changes of annual and seasonal runoff of 1919–2011 at the outlet station, that is, Huaxian station, in the mainstream of Weihe River. The results show that the runoff variation point is 1990, and there were significant changes in trends and periodicals, corroborated by wavelet variance analysis, Kendall’s rank tests, and trends persistence test, in annual, seasonal, and monthly runoff at the variation point of 1990. Attribution analysis indicates that the primary drivers of the shift in runoff variation were human activities rather than climate change, as water consumption (particularly groundwater consumption) increased sharply in the 1990s.


Symmetry ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1340 ◽  
Author(s):  
Yaxue Zuo ◽  
Zhenya Wang

Product evaluation is very important for product improvement and development, and subjective product evaluation determines customer’s evaluation of products to some extent, so the purpose of this study is to establish a reasonable subjective product evaluation system. In this study, we comprehensively determine the evaluation indexes based on Kansei engineering (KE), establish an overall product evaluation system by using analytic hierarchy process (AHP), and establish the subjective product evaluation system by classifying the evaluation indexes in the overall product evaluation system into “objective evaluation index” and “subjective evaluation index”, removing the objective evaluation indexes, and retaining the subjective evaluation indexes. Additionally, we select some modern chairs as experimental samples to verify the reliability and validity of this subjective product evaluation system by means of questionnaires. The experimental results show that, in this subjective product evaluation system, the subjective evaluation of the product is positively correlated with the “favorite” level of the product in comprehensive evaluation, and negatively correlated with the “least favorite” level of the product in comprehensive evaluation, indicating that this subjective product evaluation system realizes a symmetry between subjective product evaluation and comprehensive product evaluation. Therefore, it can be concluded that this subjective product evaluation system based on KE and AHP proposed in this study has reliability and validity, and can be used for product evaluation to judge the popularity of products and enhance the competitiveness of products.


2019 ◽  
Vol 98 ◽  
pp. 01034 ◽  
Author(s):  
Mingjun Liu ◽  
Changlai Xiao ◽  
Xiujuan Liang

In this study, a hydrochemical investigation was conducted in Shuangliao city to identify the hydrochemical characteristics and the quality of groundwater using descriptive statistics and correlation matrices. And on that basis, combined with Analytic hierarchy process (AHP), an improved two-level fuzzy comprehensive evaluation method is used to evaluate the groundwater quality. The results indicate that the major cations and anions in groundwater are Ca2+ and HCO3-, respectively. The chemical types are mainly HCO3—Ca type water, some areas are complicated due to the influence of human activities. The evaluation results show that the water quality in the area is mostly III type water, and the groundwater quality in some areas is IV or V water due to the influence of primary geological conditions or human activities. The groundwater quality in the East Liaohe River Valley and Shuangliao urban area is relatively poor, and in the northwest part which is the saline alkali soil area is also relatively poor.


2013 ◽  
Vol 756-759 ◽  
pp. 715-719
Author(s):  
Huan Cheng Zhang ◽  
Ya Feng Yang ◽  
Feng Li ◽  
Li Nan Shi

In the College, performance evaluation system is directly related to the harmonious development of the school. Taking into account the factors in the evaluation system is fuzzy, so this paper uses fuzzy comprehensive evaluation model. But the model is too subjective, so this paper combines neural network and data envelopment analysis method, which ensures that fuzzy comprehensive evaluation model is reasonable and scientific, and good school development and teacher self-interest. The performance assessment process, not only enables the combination of qualitative and quantitative analysis, but also fair and reasonably reflect the achievements of teachers, while this method is easy to use, wide application, and can be well applied in practice.


Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1237 ◽  
Author(s):  
Caihong Hu ◽  
Li Zhang ◽  
Qiang Wu ◽  
Shan-e-hyder Soomro ◽  
Shengqi Jian

Runoff reduction in most river basins in China has become a hotpot in recent years. The Gushanchuan river, a primary tributary of the middle Yellow river, Northern China, showed a significant downward trend in the last century. Little is known regarding the relative contributions of changing environment to the observed hydrological trends and response on the runoff generation process in its watershed. On the basis of observed hydrological and meteorological data from 1965–2010, the Mann-Kendall trend test and climate elasticity method were used to distinguish the effects of climate change and human activities on runoff in the Gushanchuan basin. The results indicate that the runoff in the Gushanchuan Basin has experienced significant declines as large as 77% from 1965 to 2010, and a mutation point occurred around 1997; the contribution rate of climate change to runoff change is 12.9–15.1%, and the contribution rate of human activities to runoff change is 84.9–87.1%. Then we divided long-term data sequence into two stages around the mutation point, and analyzed runoff generation mechanisms based on land use and cover changes (LUCC). We found that the floods in the Gushanchuan Basin were still dominated by Excess-infiltration runoff, but the proportion in 1965–1997 and 1998–2010 decreased gradually (68.46% and 45.83% in turn). The proportion of Excess-storage runoff and Mixed runoff has increased, which means that the runoff is made up of more runoff components. The variation law of the LUCC indicates that the forest area increased by 49.61%, the confluence time increased by 50.42%, and the water storage capacity of the watershed increased by 30.35%.


2013 ◽  
Vol 291-294 ◽  
pp. 1562-1567
Author(s):  
Ji Min Hu ◽  
Jian Long Gu ◽  
Chang Cui Hu ◽  
Hai Feng Wang

According to indicators’ information repetition and subjectivity of the indicators’ weight set during the variable fuzzy comprehensive evaluation, Principal Component analysis can help solve the weight of the relative indicators and reduce comprehensive evaluation dimensions of the variable fussy comprehensive evaluation. This paper has made a comprehensive evaluation of the status quo of Yunnan’s low carbon economy development(2005-2009), which turns out to be more practical compared with the mere variable fussy theory analysis, thus, principal component-variable fuzzy evaluation is a kind of feasible way to analyze the regional low carbon development status.


2012 ◽  
Vol 433-440 ◽  
pp. 2712-2715
Author(s):  
Xiao Li Liu ◽  
Zhi Ye Zhang

Now the coal mine gas risk index and evaluation system has a lot of deficiency. The paper establishes a coal mine gas risk index system and explains the meaning of each index on the basis of analysis of gas accident for recent years. Fuzzy comprehensive evaluation has become an effective and popular method, so the paper evaluates the coal mine gas accident risk using fuzzy mathematical safety evaluation, and takes this method in six mines of one group, at last the paper provides some suggestions for this method


2010 ◽  
Vol 56 (196) ◽  
pp. 215-224 ◽  
Author(s):  
Qiao Liu ◽  
Shiyin Liu ◽  
Yong Zhang ◽  
Xin Wang ◽  
Yingsong Zhang ◽  
...  

AbstractTemperate glaciers are more sensitive to climate changes than polar or continental glaciers, and can drive remarkable runoff variation in local water catchments. Here we present recent glacier shrinkage and runoff change for Hailuogou glacier, a typical monsoon temperate glacier on the east slope of Mount Gongga (Minya Konga), China. The surface area of Hailuogou glacier has decreased by 3.5% (0.92 km2) between 1966 (aerial photographs) and 2007 (ASTER images). Flow measurements at a stream gauge about 500 m down-glacier commencing in 1994 display a remarkable increase in annual runoff (mostly during July–September) since 1999. Annual runoff over the same period in a nonglacierized but forested subcatchment (9.17 km2) did not experience significant change. By separating the daily rainfall component from the daily total discharge, monthly catchment water-balance series were calculated for the period 1994–2005, which shows an increasing trend of glacier storage loss. We concluded that air-temperature rise (with a trend of +0.2°C (10 a)−1 between 1988 and 2005, recorded at nearby weather stations) has had an increased effect on glacier mass loss and river runoff change during the past 20 years.


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