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Introduction: As China continues to develop the advanced power systems, the network structure of distribution networks is becoming increasingly complex. The integration of numerous power electronic devices has caused growing severity of power quality issues in present-day distribution networks. Moreover, the complexity of the networks has resulted in a significant increase in the volume of power quality data, posing greater challenges in data processing and power quality assessment. Methods: This paper investigates a novel method for comprehensive assessment of power quality in advanced distribution networks (ADN) grounded in complex network theory. First, the influencing factors of power quality in advanced distribution networks are analyzed, and based on this analysis, the power quality evaluation indicators for advanced distribution networks are determined. Then a node characteristic matrix of the distribution network is constructed based on complex network theory which is used to generate the significance of each node within the network. Moreover, the sequential relationship analysis method (G1) and criteria importance though intercrieria correlation (CRITIC) method are leveraged to determine the subjective and objective weights of each indicator. These weights are then combined to calculate the comprehensive weight, which is further optimized using a two-stage method to increase the rationality. Furthermore, a fuzzy comprehensive evaluation method is applied to quantitatively assess the power quality within ADN. Finally, the proposed method is validated using measurement data from a specific ADN. Results and discussion: The findings demonstrate the rationality and effectiveness of the proposed method, providing valuable insights for optimizing power quality of advanced distribution systems. [ABSTRACT FROM AUTHOR]

IntroductionAs China continues to develop the advanced power systems, the network structure of distribution networks is becoming increasingly complex. The integration of numerous power electronic devices has caused growing severity of power quality issues in present-day distribution networks. Moreover, the complexity of the networks has resulted in a significant increase in the volume of power quality data, posing greater challenges in data processing and power quality assessment.MethodsThis paper investigates a novel method for comprehensive assessment of power quality in advanced distribution networks (ADN) grounded in complex network theory. First, the influencing factors of power quality in advanced distribution networks are analyzed, and based on this analysis, the power quality evaluation indicators for advanced distribution networks are determined. Then a node characteristic matrix of the distribution network is constructed based on complex network theory which is used to generate the significance of each node within the network. Moreover, the sequential relationship analysis method (G1) and criteria importance though intercrieria correlation (CRITIC) method are leveraged to determine the subjective and objective weights of each indicator. These weights are then combined to calculate the comprehensive weight, which is further optimized using a two-stage method to increase the rationality. Furthermore, a fuzzy comprehensive evaluation method is applied to quantitatively assess the power quality within ADN. Finally, the proposed method is validated using measurement data from a specific ADN.Results and discussionThe findings demonstrate the rationality and effectiveness of the proposed method, providing valuable insights for optimizing power quality of advanced distribution systems.

The mental health of college students is closely linked to their upbringing environment. This study utilized a scale method to quantitatively assess family economic status, parenting styles, and closeness using subjective and objective induction perspectives. The survey data was obtained by combining Liket multipoint scoring, and the Cronbach’s alpha coefficient was utilized for testing. For the mental health assessment of college students, quantification and summation was conducted through fuzzy qualitative assessment, and the assessment criteria were established using the fuzzy comprehensive assessment method. The predictions were fitted using multiple linear regression after completing the descriptive statistical analysis and mediating role test. The family socioeconomic status factor was used to predict the mental health index of college students, which could reduce the error by 3.8%. The parenting style factor was used to predict the mental health index of college students, which could reduce 7.2% of the error. Using the factor of family closeness to predict the mental health index of college students can reduce the error by 4.2%. By exploring the influence of upbringing on mental health, psychological intervention methods can be better proposed.

Through a case study to the gas pipeline network of Suzhou Industrial Park, a corrosion risk assessment model of gas pipeline network was established in combination with the risk assessment theory to assess the corrosion risk of the gas pipeline network in the industrial park. The assessment model adopted the fuzzy comprehensive evaluation method based on the improved AHP. By establishing the corrosion risk index system of gas pipeline network, the weight of each index was determined with the improved AHP method, the corrosion risk assessment level was established with the fuzzy comprehensive evaluation method, and finally the risk level of each pipeline section in the industrial park was solved. Excavation inspection was conducted for six gas pipelines in Suzhou Industrial Park randomly selected to judge the corrosion status of the pipeline, and the inspection results were compared with the evaluation results. The results show that the corrosion risk model can accurately assess the risk status of the gas pipeline network, and it is of some significance to improve the early warning and management level of the corrosion risk of city gas pipelines.

Spatial and temporal variation of water quality in two main tributaries of Yellow River was characterized with statistical methods including Discriminant Analysis (DA), Principal Component Analysis (PCA) and Factor Analysis (FA). The DA analysis determined the most significant parameters for spatial discrimination in the rivers: biological oxygen demand (BOD5) and total phosphorous (TP) for Luohe River and BOD5, total nitrogen (TN) and TP for Yihe River. The temporal discrimination of the water quality in the rivers mainly depended on the variables influenced by natural environmental process including, water temperature (WT), dissolved oxygen (DO) and pH. The variance factors obtained from the PCA/FA analysis suggested that the parameters associated with organic pollution and nutrient pollution accounted for water quality variations mostly. The FCA results showed that the water quality of the two rivers was higher than the water quality requirement in the water functional zones and got better in recent years. The temporal trend of the water quality in the two rivers showed that all the environmental actions implemented by the local government in the last years are contributive to the water quality upgrade in the region and should be kept or implemented more stringently in the future. [ABSTRACT FROM AUTHOR]

Ultra-shallow-buried and large-span double-arch tunnels face complex risks during construction. The risk sources are hidden, complicated, and diverse. The dynamic risk assessment problem cannot be solved satisfactorily by using the static method as an insufficient amount of research has been conducted. The land part of the Xiamen Haicang double-arch tunnel was selected as the background for the dynamic risk assessment of ultra-shallow-buried and large-span double-arch tunnel construction. The construction process was divided into five stages: pre-construction preparation; ground and surrounding rock reinforcement; pilot tunnel excavation; and the single-and the double-tunnel excavations of the main tunnel. Through consultation with tunnel experts, six first-level and thirty second-level risk evaluation indexes were proposed. The benchmark weight of the dynamic risk assessment index was determined by using the analytic hierarchy process. The weight of the risk evaluation index was revised according to the monitoring data and the construction stage. The fuzzy evaluation matrix of the construction risk membership degree was obtained by using the fuzzy comprehensive assessment method, and the calculation results were analyzed using the subsection assignment method. Control measures were suggested according to the risk assessment results. The risk assessment result of the double tunnel excavation stage of the main tunnel was level II, and the risk level was the highest among the five construction stages. The risk assessment result of the ground and surrounding rock reinforcement stage was level IV, and the risk level was the lowest. The dynamic construction safety risk assessment based on the fuzzy comprehensive assessment method is more timely, accurate, and reasonable than the traditional assessment method. The method can be adopted in similar engineering projects. [ABSTRACT FROM AUTHOR]

PHM technology plays an increasingly significant role in modern aviation condition-based maintenance. As an important part of prognostics and health management (PHM), a health assessment can effectively estimate the health status of a system and provide support for maintenance decision making. However, in actual conditions, various uncertain factors will amplify assessment errors and cause large fluctuations in assessment results. In this paper, uncertain factors are incorporated into flight control system health assessment modeling. First, four uncertain factors of health assessment characteristic parameters are quantified and described by the extended λ-PDF method to acquire their probability distribution function. Secondly, a Monte Carlo simulation (MCS) is used to simulate a flight control system health assessment process with uncertain factors. Thirdly, the probability distribution of the output health index is solved by the maximum entropy principle. Finally, the proposed model was verified with actual flight data. The comparison between assessment results with and without uncertain factors shows that a health assessment conducted under uncertain conditions can reduce the impact of the uncertainty of outliers on the assessment results and make the assessment results more stable; therefore, the false alarm rate can be reduced. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology 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 Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)

Ultra-shallow-buried and large-span double-arch tunnels face complex risks during construction. The risk sources are hidden, complicated, and diverse. The dynamic risk assessment problem cannot be solved satisfactorily by using the static method as an insufficient amount of research has been conducted. The land part of the Xiamen Haicang double-arch tunnel was selected as the background for the dynamic risk assessment of ultra-shallow-buried and large-span double-arch tunnel construction. The construction process was divided into five stages: pre-construction preparation; ground and surrounding rock reinforcement; pilot tunnel excavation; and the single-and the double-tunnel excavations of the main tunnel. Through consultation with tunnel experts, six first-level and thirty second-level risk evaluation indexes were proposed. The benchmark weight of the dynamic risk assessment index was determined by using the analytic hierarchy process. The weight of the risk evaluation index was revised according to the monitoring data and the construction stage. The fuzzy evaluation matrix of the construction risk membership degree was obtained by using the fuzzy comprehensive assessment method, and the calculation results were analyzed using the subsection assignment method. Control measures were suggested according to the risk assessment results. The risk assessment result of the double tunnel excavation stage of the main tunnel was level II, and the risk level was the highest among the five construction stages. The risk assessment result of the ground and surrounding rock reinforcement stage was level IV, and the risk level was the lowest. The dynamic construction safety risk assessment based on the fuzzy comprehensive assessment method is more timely, accurate, and reasonable than the traditional assessment method. The method can be adopted in similar engineering projects.

PHM technology plays an increasingly significant role in modern aviation condition-based maintenance. As an important part of prognostics and health management (PHM), a health assessment can effectively estimate the health status of a system and provide support for maintenance decision making. However, in actual conditions, various uncertain factors will amplify assessment errors and cause large fluctuations in assessment results. In this paper, uncertain factors are incorporated into flight control system health assessment modeling. First, four uncertain factors of health assessment characteristic parameters are quantified and described by the extended λ-PDF method to acquire their probability distribution function. Secondly, a Monte Carlo simulation (MCS) is used to simulate a flight control system health assessment process with uncertain factors. Thirdly, the probability distribution of the output health index is solved by the maximum entropy principle. Finally, the proposed model was verified with actual flight data. The comparison between assessment results with and without uncertain factors shows that a health assessment conducted under uncertain conditions can reduce the impact of the uncertainty of outliers on the assessment results and make the assessment results more stable; therefore, the false alarm rate can be reduced.

In order to study resource metabolism level of complex ecosystem in coal mining area, this paper constructed the resource flow structure diagram of the integrated ecosystem in coal mining area by using the material flow analysis method and energy analysis method, and put forward the evaluation index system of resource metabolism with four stages of resource input, resource utilization, environmental stress and recycling. The fuzzy comprehensive evaluation model of resource metabolism is established, and the weight of each index is determined by the improved analytic hierarchy process. Taking the Tiefa Dalong coal mining area in Liaoning as the research object, an empirical study was conducted. The results of study show that the resource metabolism of Dalong coal mine is at a lower level, in which the input of resources is large and the utilization efficiency of resources is low. The development of coal resources in Dalong coal mine has a large discharge of pollutants, and it is heavy on environmental pollution and stress. The level of resource recycling is low which triggers a series of environmental and ecological problems. Suggestions for improving the metabolic function of resources are given. [ABSTRACT FROM AUTHOR]

Copyright of Research of Environmental Sciences is the property of Research of Environmental Sciences Editorial Board 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.)

Quantitative assessment of water quality and its spatial variation identification, as well as the discernment of primary factors affecting water quality are in its urgent in water environment management. In this study, four key water quality indicators, namely, ammonia nitrogen (NH -N), permanganate index (COD), total phosphorus (TP) and total nitrogen (TN) at 71 sampling sites were selected to evaluate water quality and its spatial variation identification. More concerns were emphasized on the anthropogenic factors (land use pattern) and natural factors (river density, elevation and precipitation) to quantify the overall water quality variations at different spatial scales. Results showed that the Yi-Shu-Si River sub-basin had a better water quality status than the Huai River sub-basin. The moderate polluted area nearly distributed in the upper and middle reaches of the Shaying River and Guo River. The high cluster centers which were surrounded with COD, NH -N, TN and TP mainly also distributed in the upper and middle reaches of the Shaying River and Guo River. Redundancy analysis showed that the 200 m buffer area acted as the most sensitive area, which was easily subjected to pollution. The precipitation was identified as the most important variables among all the studied hydrological units, followed by farmland, urban land or elevation. The point source pollution was still existed although the non-point source pollution was also identified. The urban surface runoff pollution was severer than farmland fertilizer loss at the sub-basin scale in flood season, while the farmland showed 'small-scale' effects for explaining overall water quality variations. This research is helpful for identifying the overall water quality variations from the scale-process interactions and providing a scientific basis for pollution control and decision making for the Huai River Basin. [ABSTRACT FROM AUTHOR]

This paper deals with assessment of air quality in Haora River basin using two techniques. Initially, air quality indices were evaluated using a modified EPA method. The indices were also evaluated using a fuzzy comprehensive assessment (FCA) method. The results obtained from the fuzzy comprehensive assessment method were compared to that obtained from the modified EPA method. To illustrate the applicability of the methodology proposed herein, a case study has been presented. Air samples have been collected at 10 sampling sites located along Haora River. Six important air pollutants, namely, carbon monoxide, sulfur dioxide, nitrogen dioxide, suspended particulate matter (SPM), PM, and lead, were monitored continuously, and air quality maps were generated on the GIS platform. Comparison of the methodologies has clearly highlighted superiority and robustness of the fuzzy comprehensive assessment method in determining air quality indices under study. It has effectively addressed the inherent uncertainties involved in the evaluation, modeling, and interpretation of sampling data, which was beyond the scope of the traditional weighted approaches employed otherwise. The FCA method is robust and prepares a credible platform of air quality evaluation and identification, in face of the uncertainties that remain eclipsed in the traditional approaches like the modified EPA method. The insights gained through the present study are believed to be of pivotal significance in guiding the development and implementation of effective environmental remedial action plans in the study area. [ABSTRACT FROM AUTHOR]

This study aimed to assess the quality of groundwater and potential health risk due to ingestion of heavy metals in the peri-urban and urban-industrial clusters of Ghaziabad district, Uttar Pradesh, India. Furthermore, the study aimed to evaluate heavy metals sources and their pollution level using multivariate analysis and fuzzy comprehensive assessment (FCA), respectively. Multivariate analysis using principle component analysis (PCA) showed mixed origin for Pb, Cd, Zn, Fe, and Ni, natural source for Cu and Mn and anthropogenic source for Cr. Among all the metals, Pb, Cd, Fe and Ni were above the safe limits of Bureau of Indian Standards (BIS) and World Health Organization (WHO) except Ni. Health risk in terms of hazard quotient (HQ) showed that the HQ values for children were higher than the safe level (HQ = 1) for Pb (2.4) and Cd (2.1) in pre-monsoon while in post-monsoon the value exceeded only for Pb (HQ = 1.23). The health risks of heavy metals for the adults were well within safe limits. The finding of this study indicates potential health risks to the children due to chronic exposure to contaminated groundwater in the region. Based on FCA, groundwater pollution could be categorized as quite high in the peri-urban region, and absolutely high in the urban region of Ghaziabad district. This study showed that different approaches are required for the integrated assessment of the groundwater pollution, and provides a scientific basis for the strategic future planning and comprehensive management. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency 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 Transactions of Beijing Institute of Technology is the property of Beijing University of Technology 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 fuzzy comprehensive assessment was undertaken to evaluate the marine sediment quality in Daya Bay, China based on the monitoring data of 2015 and China National Standard for Marine Sediment Quality (GB 18668-2002). The results demonstrated that the average metal concentrations (mg/kg) were 0.08 (Cd), 51.30 (Pb), 91.30 (Cr), 29.63 (Cu), 143.42 (Zn), 0.03 (Hg), and 7.31 (As), which were clearly higher with respect to their corresponding background values. Cr was the major pollutant based weight matrices calculated. Taken as whole, the membership degree of class I was a range from 0.65 to 1, suggesting that the marine sediment quality in Daya Bay belongs to class I. Pb stable isotopic analysis coupled with geographic information system (GIS) approach showed the sedimentary Pb mainly originated from petrochemical industry at northwest coast of Daya Bay. [ABSTRACT FROM AUTHOR]

Stadium buildings are important population-intensive buildings where various social activities are held frequently. The quakeproof property of stadium buildings directly concerns safety and image of social people and the cities. This research takes sports stadium buildings for example, combines architectural characteristics and quakeproof requirements of sports stadium and introduces fuzzy assessment theory. Deep analysis is carried out from the site environment, foundation, major structure, building materials and components which influence quakeproof property. On this basis, this paper proposes a set of scientific comprehensive assessment index system, and applies fuzzy comprehensive assessment to construct quakeproof property assessment model of sports stadium. Meanwhile, based on case study of Wukesong Stadium, this paper verifies feasibility of this assessment system. The research shows that this method has certain reference significance for quakeproof property assessment of similar stadiums. [ABSTRACT FROM AUTHOR]

Fuzzy comprehensive assessment and multivariate statistical techniques including cluster analysis, discriminant analysis, principal component analysis, and factor analysis were applied to analyze the water quality status of Yuqiao Reservoir Basin, North China, for assessing its spatio-temporal variations and identifying potential pollution sources. In this paper, we considered data for 14 water quality parameters collected during 1990-2004 at 7 water quality monitoring sites. The results of fuzzy comprehensive assessment revealed that water quality in Yuqiao Reservoir Basin showed a downtrend from 1990 to 2001 with fluctuation, and a slowly upward trend after 2001. The major water quality belonged to Class III and IV. Besides, hierarchical cluster analysis divided 7 monitoring sites into two groups (Group A and B), and 12 months into three periods (low-flow (LF), normal-flow (NF), and high-flow (HF) period). Temp, pH, SS, T-har, DO, NO-N and TP were identified as significant variables affecting spatial variations, and Temp, pH and NO-N were identified as significant variables affecting temporal variations by discriminant analysis. Factor analysis identified four latent pollution sources for water quality variations: nutrient pollution, organic pollution, inorganic pollution, and natural pollution. Moreover, for Group A regions, pollution inputs mainly came from domestic wastewater and industrial sewage. For Group B regions, it is more likely that water pollution resulted from the combined effects of domestic wastewater, hospital wastewater, agriculture runoff, and fishpond discharge, as well as the incoming water from upstream. [ABSTRACT FROM AUTHOR]

Understanding the spatio-temporal variation and the potential source of water pollution could greatly improve our knowledge of human impacts on the environment. In this work, data of 11 water quality indices were collected during 2012-2014 at 10 monitoring sites in the mainstream and major tributaries of the Danjiangkou Reservoir Basin, Central China. The fuzzy comprehensive assessment (FCA), the cluster analysis (CA) and the discriminant analysis (DA) were used to assess the water pollution status and analyze its spatio-temporal variation. Ten sites were classified by the high pollution (HP) region and the low pollution (LP) region, while 12 months were divided into the wet season and the dry season. It was found that the HP region was mainly in the small tributaries with small drainage areas and low average annual discharges, and it was also found that most of these rivers went through urban areas with industrial and domestic sewages input into the water body. Principal component analysis/factor analysis (PCA/FA) was applied to reveal potential pollution sources, whereas absolute principal component score-multiple linear regression (APCS-MLR) was used to identify their contributions to each water quality variable. The study area was found as being generally affected by industrial and domestic sewage. Furthermore, the HP region was polluted by chemical industries, and the LP region was influenced by agricultural and livestock sewage. [ABSTRACT FROM AUTHOR]

Boilers are key industrial equipment in the field of modern manufacturing. In this study, rule-based reasoning (RBR) and case-based reasoning (CBR) are applied into the boiler intelligent design. RBR is adopted to perform like a 'sieve' for the acquisition of candidate structure modules. Then, fuzzy comprehensive assessment method is used to select an optimal structure module among the candidates. The optimal structure module is subjected to the CBR process, which includes modification and case retention. It is a minor adjustment process that needs a great amount of prior knowledge. The case retention process gives the system a self-enrich function, which will improve the design ability of the system with continuous use of the system. A case study is presented to validate the correctness and efficiency of proposed method. [ABSTRACT FROM AUTHOR]

This study presents a data analysing method and an assessment system for manufacturing process. The data analysing is based on the data collection, performance indicators and data quantification. The system can be used to provide detailed information on the overall resources consumption and the environmental impact, where fuzzy comprehensive assessment is utilised to calculate the evaluation score for the manufacturing process. The feasibility of this system is demonstrated by the manufacturing process of a valve body J61Y-20 DN40. [ABSTRACT FROM PUBLISHER]

Characterizing water quality and identifying potential pollution sources could greatly improve our knowledge about human impacts on the river ecosystem. In this study, fuzzy comprehensive assessment (FCA), pollution index (PI), principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) were combined to obtain a deeper understanding of temporal-spatial characterization and sources of water pollution with a case study of the Jinjiang River, China. Measurement data were obtained with 17 water quality variables from 20 sampling sites in the December 2010 (withered water period) and June 2011 (high flow period). FCA and PI were used to comprehensively estimate the water quality variables and compare temporal-spatial variations, respectively. Rotated PCA and receptor model (APCS-MLR) revealed potential pollution sources and their corresponding contributions. Application results showed that comprehensive application of various multivariate methods were effective for water quality assessment and management. In the withered water period, most sampling sites were assessed as low or moderate pollution with characteristics pollutants of permanganate index and total nitrogen (TN), whereas 90 % sites were classified as high pollution in the high flow period with higher TN and total phosphorus. Agricultural non-point sources, industrial wastewater discharge, and domestic sewage were identified as major pollution sources. Apportionment results revealed that most variables were complicatedly influenced by industrial wastewater discharge and agricultural activities in withered water period and primarily dominated by agricultural runoff in high flow period. [ABSTRACT FROM AUTHOR]

This paper introduces an improved fuzzy comprehensive evaluation model specially designed for the safety culture assessment of petroleum enterprises. The model is established based on the authors’ years of experience in this field. The index system of the safety assessment mentioned herein is based on SMART safety culture principles, covering safety material, safety behavior, safety system, safety belief, persistence of safety, and openness of safety. The proposed system also includes the safety material culture, in which on-the-spot analysis of the key factors of safety culture is conducted together with duty consultants. All the fuzzy membership indexes and their degrees were weighed and calculated with the final evaluation results, presented in accordance with the analytic hierarchy process. All the safety culture statuses of petroleum enterprises Z, S, and C were then incorporated into detailed analysis. The results of the application confirm that the levels of safety culture follow the order of Z petroleum enterprise