scholarly journals Ecosystem-Based Quality Index in a harbor bay: Assessing the status of a heterogeneous system in a functional framework at a local scale

2021 ◽  
Vol 132 ◽  
pp. 108260
Author(s):  
Filippo Ferrario ◽  
Ladd E. Johnson ◽  
Christopher W. McKindsey ◽  
Philippe Archambault
Keyword(s):  
Quality Index ◽  
Heterogeneous System ◽  
Local Scale ◽  
The Status

scholarly journals Can Habitat Quality Index Measured Using the InVEST Model Explain Variations in Bird Diversity in an Urban Area?

2021 ◽  
Vol 13 (10) ◽  
pp. 5747
Author(s):  
Dehuan Li ◽  
Wei Sun ◽  
Fan Xia ◽  
Yixuan Yang ◽  
Yujing Xie
Keyword(s):  
Habitat Quality ◽  
Quality Index ◽  
Empirical Studies ◽  
Species Abundance ◽  
Diversity Indices ◽  
Local Scale ◽  
Data Availability ◽  
Bird Diversity ◽  
Invest Model ◽  
Trade Offs

Biodiversity maintenance is a crucial ecosystem service. Due to time limits and data availability, assessing biodiversity using indicators or models has become a hot topic in recent decades. However, whether some proposed indicators can explain biodiversity well at the local scale is still unclear. This study attempted to test whether the habitat quality index (HQI) as measured using the integrated valuation of ecosystem services and trade-offs (InVEST) model could explain variations in bird diversity in New Jiangwan Town, a rapidly urbanized region of Shanghai, China. The relationships from 2002 to 2013 among HQI and the two diversity indices, species richness and species abundance, were analyzed using Fisher’s exact test and gray correlation analysis. No significant association was found. Habitat connectivity was then integrated to develop a new combined indicator of habitat quality and connectivity index (HQCI). The associations between HQCI and the two diversity indices were improved significantly. The results indicated that connectivity may be an important factor explaining the diversity of certain species at a local scale. More empirical studies should be conducted to provide scientific evidence relating habitat quality to biodiversity.

Local Scale Covariance and Its Radical Implications for Cosmology

Galaxies ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 76
Author(s):  
Yehonatan Knoll
Keyword(s):  
Local Scale ◽  
Covariant Theory ◽  
De Sitter ◽  
Cosmological Redshift ◽  
Physical Limit ◽  
Scale Covariance ◽  
The Status ◽  
Scale Motion ◽  
Fundamental Equations ◽  
Conceptual Foundations

Local scale covariance posits that no privileged length scales should appear in the fundamental equations of local, Minkowskian physics—why should nature have scale, but not position preferences?—yet, they clearly do. A resolution is proposed wherein scale covariance is promoted to the status of Poincaré covariance, and privileged scales emerge as a result of `scale clustering’, similarly to the way privileged positions emerge in a translation covariant theory. The implied ability of particles to `move in scale’ has recently been shown by the author to offer a possible elegant solution to the missing matter problem. For cosmology, the implications are: (a) a novel component of the cosmological redshift, due to scale-motion over cosmological times; (b) a radically different scenario for the early universe, during which the conditions for such scale clustering are absent. The former is quantitatively analyzed, resulting in a unique cosmological model, empirically coinciding with standard Einstein–de-Sitter cosmology, only in some non-physical limit. The latter implication is qualitatively discussed as part of a critique of the conceptual foundations of ΛCDM which ignores scale covariance altogether.

Assessing and Extending Track Quality Index for Novel Measurement Techniques in Railway Systems

2020 ◽  
Vol 2674 (8) ◽  
pp. 24-36
Author(s):  
Tzu-Hao Yan ◽  
Francesco Corman
Keyword(s):  
Quality Index ◽  
Measurement Techniques ◽  
High Sensitivity ◽  
Single Type ◽  
Railway Systems ◽  
The Status ◽  
Sensitivity Data ◽  
Maintenance Process ◽  
Track Status ◽  
Track Quality

A systematic maintenance process is essential to keeping railway systems safe and reliable. However, performing such maintenance is costly and often results in system disruption. There is a tradeoff between system safety and budgetary constraints; understanding the condition of the track infrastructure is essential to find the balance between needs and costs for decisions about when to perform maintenance. In this study, the track quality index (TQI), which is commonly used to evaluate the status of tracks and to decide maintenance interventions, is reviewed, including 12 TQIs for superstructure and six for substructure. A literature review indicates that TQIs for sleepers and subgrade have not yet been developed. The differences between TQIs are compared using a set of hypothetical raw data. Their capabilities for identifying track irregularities are also investigated based on the EN 13848 regulations. To classify TQI characteristics in a systematic way, this study proposes four concepts: accuracy, sensitivity, data required, and specificity. Accuracy indicates a TQI’s capability of detecting defects; sensitivity indicates how TQIs change according to variations in the defects; specificity relates to the amount of parameters considered, and the ability to pinpoint root causes or global consequences of defects. The results suggest a tradeoff between the four concepts, where high sensitivity can increase the ability to detect the smallest defects but may be affected by bias; more parameters considered may indicate low accuracy when detecting a single type of defect. Therefore, this study suggests railway regulators use multiple TQIs with complementary characteristics for classifying track status.

Air Quality Index-A Comparative Study for Assessing the Status of Air Quality

2015 ◽  
Vol 6 (2) ◽  
pp. 267 ◽  
Author(s):  
Shivangi Nigam ◽  
B.P.S. Rao ◽  
N. Kumar ◽  
V. A. Mhaisalkar
Keyword(s):  
Air Quality ◽  
Comparative Study ◽  
Quality Index ◽  
Air Quality Index ◽  
The Status

scholarly journals Ecological assessment of East Hammar marsh, Iraq using a number of ecological guides

2017 ◽  
Vol 26 (2) ◽  
pp. 11-22
Author(s):  
Abdul-Razak Abdul-Razak
Keyword(s):  
Quality Index ◽  
Historical Data ◽  
Ecological Status ◽  
Ecological Assessment ◽  
Trophic State Index ◽  
Biological Index ◽  
The Status ◽  
State Index ◽  
Assemblage Metrics ◽  
Better Than

The ecological status of the East Hammar marsh was evaluated by using a number of ecological guides: water quality index (WQI), Carlson trophic state index (TSI) and fish integrated biological index (F-IBI) during the period from November 2012 to October 2013. The results revealed that the annual value of WQI varied from 51.1 (marginal) for historical data before desiccation to 67.8 (fair) for data after inundation. The marsh was evaluated to be mesotrophic (TSI= 42.0). IBI scores were calculated from 16 separate assemblage metrics based on the fish species richness, species composition and trophic guilds. The ecological status of the marsh was found to be fair (F-IBI= 47.7) and was slightly better than the status of the marsh after 2-4 years of restoration activities. The rather low improvement in the situation of the marsh indicates that the environment is still fragile and requires the allocation of water share from the Tigris and Euphrates rivers to restore marsh normality.

scholarly journals Application of Water Quality Index (WQI) for groundwater quality assessment of Biratnagar, Nepal

Our Nature ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 54-61
Author(s):  
Bishnu Dev Das ◽  
Sunil Kumar Choudhary
Keyword(s):  
Water Quality ◽  
Groundwater Quality ◽  
Water Quality Index ◽  
Quality Index ◽  
Total Hardness ◽  
Monsoon Period ◽  
Groundwater Samples ◽  
Tube Wells ◽  
The Status ◽  
Free Carbon Dioxide

This present hydrological study assessed the groundwater quality of Biratnagar Metropolitan by the application of Water Quality Index (WQI). It has been determined on the basis of analyzed groundwater samples for some important physicochemical parameters such as pH, turbidity, electrical conductivity (EC), dissolved oxygen (DO), free carbon-dioxide (FCO2), bicarbonate (HCO3), total hardness (TH), phosphate (PO4-P), nitrate-N (NO3-N), arsenic (As), and fluoride (Fl) collected from 110 representative tube wells during post-monsoon period of 2015. The status of fluoride was below detectable level (BDL) in all the analyzed groundwater samples. The WQI for these samples ranged from 84.54 to 403.14. The high value of WQI has been found mainly due to the higher values of turbidity, FCO2 and arsenic in the groundwater. The results of study have been used to recommend models for predicting water quality. The classification of water quality on the basis of WQI value have been found to be good water (18.18%), poor water (59.09%), very poor water (13.64%) and unsuitable for drinking (9.09%). The result of the study suggests that the groundwater of the area needs some degree of treatment before consumption, and it also needs to be protected from the threat of contamination. The groundwater is one of the major source of drinking water as well as for irrigation in study area.

scholarly journals Fuzzy Logic Water Quality Index and Importance of Water Quality Parameters

2009 ◽  
Vol 2 ◽  
pp. ASWR.S2156 ◽  
Author(s):  
Bai V Raman ◽  
Reinier Bouwmeester ◽  
S Mohan
Keyword(s):  
Water Quality ◽  
Fuzzy Logic ◽  
Quality Index ◽  
Fuzzy Variable ◽  
Fuzzy Model ◽  
River System ◽  
Memory Device ◽  
Quality Parameters ◽  
Secondary Memory ◽  
The Status

Determination of status of water quality of a river or any other water sources is highly indeterminate. It is necessary to have a competent model to predict the status of water quality and to advice for type of water treatment for meeting different demands. One such model (UNIQ2007) is developed as an application software in water quality engineering. The unit operates in a fuzzy logic mode including a fuzzification engine receiving a plurality of input variables on its input and being adapted to compute membership function parameters. A processor engine connected downstream of the fuzzification unit will produce fuzzy set, based on fuzzy variable viz. DO, BOD, COD, AN, SS and pH. It has a defuzzification unit operative to translate the inference results into a discrete crisp value of WQI. The UNIQ2007 contains a first memory device connected to the fuzzification unit and containing the set of membership functions, a secondary memory device connected to the defuzzification unit and containing the set of crisp value which appear in the THEN part of the fuzzy rules and an additional memory device connected to the defuzzification unit. More advantageously, UINQ2007 is constructed with control elements having dynamic fuzzy logic properties wherein target non-linearity can be input to result in a perfect evaluation of water quality. The development of the fuzzy model with one river system is explained in this paper. Further the model has been evaluated with the data from few rivers in Malaysia, India and Thailand. This water quality assessor probe can provide better quality index or identify the status of river with 90% perfection. Presently, WQI in most of the countries is referring to physic-chemical parameters only due to great efforts needed to quantify the biological parameters. This study ensures a better method to include pathogens into WQI due to superior capabilities of fuzzy logic in dealing with non-linear, complex and uncertain systems.

Sign in / Sign up

Export Citation Format

Share Document